# US 2014/0191454 A1 · Telescoping spring assembly for mattresses and the like > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0191454 A1 - Document ID: US20140191454A1 - Status: Published application - Kind: A1 - Application number: 14/203,201 - Filed: 2014-03-10 - Published: 2014-07-10 - Earliest claimed: 2012-09-19 - Assignees: Otis Bed Manufacturing Company, Inc. - Applicants: Otis Bed Manufacturing Company, Inc. - Inventors: John K. Roma - Web page: https://patentgrep.com/patent/US20140191454A1 ## CPC - A47C 23/30: using combinations of springs covered by more than one of the groups A47C23/02 - A47C23/12; Frames therefor - A47C 23/0438: {of special shape} - A47C 27/063: {wrapped or otherwise protected} - F16F 1/128: {with motion-limiting means, e.g. with a full-length guide element or ball joint connections; with protective outer cover (F16F1/121 takes precedence)} - Y10T 29/49613: for human comfort - A47C: CHAIRS; SOFAS; BEDS - F16F: SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A spring assembly includes telescopically adjustable inner and outer members biased in an extension direction by a coil spring. A preload member is provided to apply a compression preload to the coil spring. The preload member can eliminate stickiness and the popping sound that are drawbacks of the prior art, and the fabric sleeve also provides general noise reduction when the spring assembly changes length. ## Claims ### Claim 1 A spring assembly, comprising: a tubular outer member including a support end and an open receiving end opposite the support end; an inner member including an insertion end and a mounting end opposite the insertion end, wherein the insertion end is received by the outer member through the open receiving end of the outer member, the outer member being telescopically movable relative to the inner member in a compression direction and an extension direction opposite from the compression direction; a coil spring arranged to bias the outer member in the extension direction relative to the inner member; and a first bumper insert arranged at a first end of the coil spring; a second bumper insert arranged at a second end of the coil spring; a preload member extending from the first bumper insert to the second bumper insert, the preload member configured to apply a compression preload to the coil spring. ### Claim 2 (depends on 1) The spring assembly of claim 1, wherein the preload member is a fabric sleeve fitted about an inner diameter and an outer diameter of the coil spring. ### Claim 3 (depends on 1) The spring assembly of claim 1, wherein the preload member is located inside the diameter of the coil spring. ### Claim 4 (depends on 3) The spring assembly of claim 3, wherein the preload member extends along approximately a center axis of the coil spring. ### Claim 5 (depends on 1) The spring assembly of claim 1, wherein the coil spring has a length, the preload member having a length that is less than the length of the coil spring. ### Claim 6 (depends on 1) The spring assembly of claim 1, wherein the first bumper insert and the second bumper insert each include an airflow passage; wherein the preload member extends through the airflow passages of the first bumper insert and the second bumper insert. ### Claim 7 (depends on 1) The spring assembly of claim 1, wherein the preload member has a length extending between the first bumper insert and the second bumper insert, the length being made of a flexible material. ### Claim 8 (depends on 7) The spring assembly of claim 7, wherein the preload member extends only along approximately a center axis of the coil spring. ### Claim 9 (depends on 1) The spring assembly of claim 1, wherein the preload member has protruded ends that extend past an end of the first bumper insert and an end of the second bumper insert. ### Claim 10 (depends on 1) The spring assembly of claim 1, wherein the first bumper insert includes a rigid housing on which an elastically deformable bumper piece is mounted and a bumper spring, wherein the coil spring has a first end bearing against the first bumper insert, the elastically deformable bumper piece being arranged to face toward the inner member and the bumper spring facing away from the inner member. ### Claim 11 (depends on 10) The spring assembly of claim 10, wherein second bumper insert includes a rigid lip, an elastically deformable bumper piece, and a bumper spring, wherein the coil spring has a second end bearing against the second bumper insert, the elastically deformable bumper piece and the bumper spring of the second insert being arranged to face the first bumper insert. ### Claim 12 (depends on 1) The spring assembly of claim 1, wherein the outer member has an exterior wall and an interior wall, the interior wall including a plurality of axially extending ribs; and wherein the plurality of axially extending ribs are spaced at regular angular intervals about the interior wall of the outer member, adjacent the open receiving end of the outer member. ### Claim 13 (depends on 12) The spring assembly of claim 12, wherein the inner member includes an external wall and a circumferential shoulder around the external wall; and wherein the compression preload of the coil spring is such that the axially extending ribs are spaced from engagement with the circumferential shoulder. ### Claim 14 (depends on 13) The spring assembly of claim 13, wherein the inner member includes an external wall and a circumferential shoulder around the external wall; and wherein the compression preload of the coil spring is such that the axially extending ribs are spaced from engagement with the circumferential shoulder. ### Claim 15 (depends on 14) The spring assembly of claim 14, wherein the compression preload to the coil spring provides a distance of about one-eighth of an inch between ends of the axially extending ribs and the circumferential shoulder when the spring assembly is at rest and free of external loading. ### Claim 16 A method of making a spring assembly, comprising: providing a tubular outer member including a support end and an open receiving end opposite the support end; providing an inner member including an insertion end and a mounting end opposite the insertion end; arranging a coil spring to bias the outer member in the extension direction relative to the inner member; and arranging a first bumper insert at a first end of the coil spring; arranging a second bumper insert at a second end of the coil spring; arranging a preload member extending from the first bumper insert to the second bumper insert, the preload member configured to apply a compression preload to the coil spring. ### Claim 17 (depends on 16) The method of claim 16, wherein the preload member is a fabric sleeve fitted about an inner diameter and an outer diameter of the coil spring. ### Claim 18 (depends on 16) The method of claim 16, wherein the preload member extends along approximately a center axis of the coil spring; wherein the preload member limits a distance between the first bumper insert and the second bumper insert. ### Claim 19 (depends on 18) The method of claim 18, wherein the preload member is arranged between the first bumper insert and the second bumper insert by driving a flexible length portion of the preload member along a center axis of the coil spring and engaging protruded ends of the preload member past an end of the first bumper insert and an end of the second bumper insert. ### Claim 20 A spring assembly, comprising: a tubular outer member including a support end and an open receiving end opposite the support end; an inner member including an insertion end and a mounting end opposite the insertion end, wherein the insertion end is received by the outer member through the open receiving end of the outer member, the outer member being telescopically movable relative to the inner member in a compression direction and an extension direction opposite from the compression direction; a coil spring arranged to bias the outer member in the extension direction relative to the inner member; and a first bumper insert arranged at a first end of the coil spring; a second bumper insert arranged at a second end of the coil spring; a preload member having a length extending from the first bumper insert to the second bumper insert and having protruded ends that extend past an end of the first bumper insert and an end of the second bumper insert; wherein the preload member, the first bumper insert, and the second bumper insert apply a compression preload to the coil spring; wherein the length of the preload member extends along approximately a center axis of the coil spring, the length of the preload member being flexible.