SEAT FRONT EDGE CONSTRUCTION
A chair includes a perimeter frame with side, front and rear sections defining an open area. A support structure includes slats and/or resilient wires supported on the perimeter frame and bridging between the side sections. A cushion of non-uniform thickness has a relatively thinner rear portion supported on the support structure and a relatively thicker front portion supported on the front section adjacent its rearwardly-facing edge. The thin rear portion of the cushion combines with the support structure to provide a transition region over the inwardly-facing edge of the front section. By this arrangement, a seated user does not sense a sudden change in supportive force across the transition region.
This application claims the benefit of U.S. Provisional Patent Application No. 60/796,081, filed Apr. 28, 2006, the entire contents of which are incorporated herein by reference.
This application is related to co-assigned co-invented patent application Ser. No. ______, filed Apr. 27, 2007 (on even date herewith), entitled “SEAT SUSPENSION AND METHOD OF MANUFACTURE,” and also related to co-assigned co-invented patent application Ser. No. ______, filed Apr. 27, 2007 (on even date herewith), entitled “SEATING CONSTRUCTION AND METHOD OF ASSEMBLY,” the entire contents of both of which are incorporated herein by reference.
BACKGROUNDThe present invention relates to seat constructions, and more particularly to seat constructions configured for improved comfort.
Seat constructions have a variety of competing functional requirements. They must support a bulk of a seated user's weight, yet they must comfortably support the seated user, regardless of what position the seated user may be in. In a “normal” upright seated position, the seated user's hips are positioned in a rear half of the seat construction, and the user's legs extend over a front edge of the seat construction. It is important that the user's legs receive distributed support so that pressure under the user's knees does not make the user uncomfortable, and also so that the pressure does not cut off good blood circulation to the user's lower legs. At the same time, comfort is not the only concern. Some users sit well forward on the seating construction, causing significant stress on the front section. Thus, the front frame section cannot be made too weak or too resilient, or the front frame section will give way, causing the seated user to feel like they are falling forward out of the chair. Other users will sit with one of their legs folding under them. Thus, the balance of support received from the front half of a seat construction as compared to the support received from the rear half is difficult to achieve when two different support systems are used, one support system being more adapted for the front support and one support system being more adapted for central/rear support of a seated user on the seat construction particularly when seated users use the seat construction in different ways. Further, seat constructions must be made to withstand some level of abuse, such as when a user may unwisely stand on the seat construction.
Recently, a new seat suspension was proposed where resilient wires were used to support a seated user over an open area inside of a perimeter frame, i.e., generally under a seated user's hips when the seated user is in a “normal” upright seated position. (See Bodnar U.S. Pat. No. 6,880,886 and also Peterson publication US2004/0245842 A1, incorporated herein by reference for their teachings.) The seat suspensions shown are very comfortable, and allow use of a relatively thin cushion on the chair to provide an attractive thin profile. Also, these seat suspensions are made of environmentally friendly materials, and are well adapted for recycling. However, improvement is desired in a front of the seat, so that a seated user does not feel uneven support under their legs (near their knees) across a transition region from the resilient wires onto a front section of the molded plastic seat frame. (See FIGS. 40, 42, and 60 in Bodnar U.S. Pat. No. 6,880,886.)
Thus, a seating construction and method of support are desired having the aforementioned advantages and solving the aforementioned problems.
SUMMARY OF THE PRESENT INVENTIONIn one aspect of the present invention, a seat construction for a seated user includes a seat frame having a front frame section and an open area rearward of the front frame section. A resilient support structure is positioned in the open area and is operably supported on the frame. The resilient support structure defines a flexible support surface that when unstressed is located in a home position that is a predetermined distance higher than a center top surface of the front frame section. The resilient support structure is flexible downwardly to a plurality of stressed positions, with at least some of the stressed positions placing a front of the support surface closer to horizontal alignment with the top surface of the front frame section and at a relative location defining a shorter distance than the predetermined distance. A cushion has a rear portion supported on the support structure and a front portion supported on the front frame section. The cushion combines with the resilient support structure to provide distributed support across a transition region extending from the open area onto the front frame section.
In another aspect of the present invention, a seat construction includes a perimeter frame defining a front frame section and further defining an open area positioned rearward of the front frame section. A support structure is supported by the perimeter frame, the support structure including a plurality of resilient supports positioned rearward of the front frame section and extending transversely across the open area, with at least a forward one of the resilient supports being higher than the front frame section. A cushion is positioned on the perimeter frame and having a first portion positioned over the resilient supports and a second portion positioned on the front frame section, a vertical thickness of the cushion in the second portion being greater than a vertical thickness of the cushion in the first portion by an amount approximately equal to a vertical spacing of the resilient supports above the front frame section.
In another aspect of the present invention, a seat construction includes a frame having spaced-apart side sections and a front frame section. A plurality of independently-bendable resilient supports are positioned rearward of the front frame section and are operably supported at ends by the side sections so as to extend across and bridge therebetween. The resilient supports when unstressed are located in a home position that is a predetermined distance higher than a top surface of the front frame section. The resilient supports each are flexible downwardly to a plurality of individually stressed positions, with at least some of the individually stressed positions placing several of the resilient supports closer to the top surface of the front frame section than others of the resilient supports.
These and other aspects, objects, and features of the present invention will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings.
A seating unit 30 (
The seat suspension 32 includes a pan-shaped molded seat frame 44, a one-piece molded component 45 defining a plurality of slats 46, resilient supports 47 attached to and resiliently supporting the slats 46 to define a comfort surface adapted to flexibly support a seated user, and an upholstered cushion 48. The subassembly of the component 45 and resilient supports 47 can be handled as a unit when placed on the molded frame 44 for assembly, thus assisting and simplifying assembly. Further, the resilient supports 47 (and the subassembly) are retained to the molded frame 44 by connecting rods 49 that extend along the side sections 50 of the molded frame 44. The slats 46 each include arcuate bearing surfaces 51 on each end that rotatably engage a mating bearing structure 52 on the molded frame 44 to define an axis of rotation aligned with the connecting rods 49. A flex-limiting member 53 (i.e. preferably a foam piece) positioned in a center of “pan-shaped” open area of the frame 44 limits the resilient supports 47 to a maximum deflected condition. Tabs 54 (
The molded frame 44 (
The front section 55 (
Notably, the cushion 48 has a non-uniform thickness, with a rear portion supported on the support structure (i.e., slats 46 and resilient supports 47) and a cushion front portion supported on the front frame section 55 adjacent the rearwardly-facing edge. The rear portion of the cushion combines with a front of the resilient support structure to provide a force-versus-deflection curve comparable to the force-versus-deflection curve provided by a combination of the cushion front portion and the front frame section, such that a seated user does not sense any sudden change in supportive force across the rearwardly-facing edge.
The side sections 50 (
A second flange 79 (
As molded, the one-piece molded component 45 includes a plurality of slats 46 (
The slats 46 (
The cushion 48 (
The illustrated slats 44 (
An alternative seating unit 130 (
As shown in
It is to be understood that variations and modifications can be made on the aforementioned structure without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.
Claims
1. A seat construction for a seated user, comprising:
- a seat frame including a front frame section and an open area rearward of the front frame section;
- a resilient support structure positioned in the open area and operably supported on the frame, the resilient support structure defining a flexible support surface that when unstressed is located in a home position that is a predetermined distance higher than a center top surface of the front frame section, the resilient support structure being flexible downwardly to a plurality of stressed positions, with at least some of the stressed positions placing a front of the support surface closer to horizontal alignment with the top surface of the front frame section and at a relative location defining a shorter distance than the predetermined distance; and
- a cushion having a rear portion supported on the support structure and a front portion supported on the front frame section, the cushion combining with the resilient support structure to provide distributed support across a transition region extending from the open area onto the front frame section.
2. The seat construction defined in claim 1, wherein the support structure includes a plurality of resilient supports that extend across the open area.
3. The seat construction defined in claim 2, wherein each of the resilient support are independently flexible and have ends operably supported on the side sections.
4. The seat construction defined in claim 3, wherein the resilient supports each include a polymeric slat and a resilient wire coupled to flex with respective ones of the slats.
5. The seat construction defined in claim 3, wherein the resilient supports include only wires.
6. The seat construction defined in claim 3, wherein the frame includes side frame sections, and ends of the resilient supports slidably engage the side frame sections.
7. The seat construction defined in claim 3, wherein the frame includes side frame sections, the side frame sections and the ends including mating bearing structures rotatably supporting the ends on the side frame sections, one of the mating bearing structures including a pair of protrusions straddling the other of the mating bearing structures.
8. The seat construction defined in claim 1, where the seat frame includes a floor panel and a perimeter frame around the floor panel, the perimeter frame including the front frame section, the floor panel supporting the flex limiter.
9. The seat construction defined in claim 1, wherein the predetermined distance is at least one half inch measured vertically from a center of the front frame section.
10. The seat construction defined in claim 1, including an upholstery cover that covers the cushion.
11. The seat construction defined in claim 1, wherein the cushion has a non-uniform thickness, including a thickened part on a rear of the front frame section near the open area.
12. The seat construction defined in claim 1, wherein the open area is defined by a rear frame section and side frame sections that combine with the front frame section to define a perimeter frame extending around the open area.
13. The seat construction defined in claim 1, wherein the frame includes a floor panel positioned under the open area.
14. The seat construction defined in claim 1, including a base frame, the frame being a seat frame supported on the base frame, the seat frame including a dished center region under the open area and the seat frame being integrally formed to include the center region.
15. A seat construction, comprising:
- a perimeter frame defining a front frame section and further defining an open area positioned rearward of the front frame section;
- a support structure supported by the perimeter frame, the support structure including a plurality of resilient supports positioned rearward of the front frame section and extending transversely across the open area, at least a forward one of the resilient supports being higher than the front frame section when in an unstressed home position; and
- a cushion positioned on the perimeter frame and having a first portion positioned over the resilient supports and a second portion positioned on the front frame section, a vertical thickness of the second portion of the cushion being greater than a vertical thickness of the first portion of the cushion by an amount approximately equal to a vertical spacing of the resilient supports above the front frame section.
16. The seat construction defined in claim 15, including a cover positioned over the cushion.
17. The seat construction defined in claim 15, wherein the frame includes marginal material extending around the open area and forming an opening.
18. The seat construction defined in claim 15, wherein the frame includes a floor panel defining a space below each of the resilient supports for receiving the resilient supports when the resilient supports are flexed.
19. A seat construction, comprising:
- a frame including spaced apart side sections and a front frame section; and
- a plurality of independently-bendable resilient supports positioned rearward of the front frame section and operably supported at ends by the side sections so as to extend across and bridge therebetween, the resilient supports when unstressed being located in a home position that is a predetermined distance higher than a top surface of the front frame section, the resilient supports each being flexible downwardly to a plurality of individually stressed positions, with at least some of the individually stressed positions placing several of the resilient supports closer to the top surface of the front frame section than others of the resilient supports.
20. The seat construction defined in claim 19, including a cushion including first and second supported on the front frame section and on the resilient supports, respectively.
Type: Application
Filed: Apr 27, 2007
Publication Date: May 8, 2008
Inventors: Kurt R. Heidmann (Grand Rapids, MI), Gordon J. Peterson (Rockford, MI)
Application Number: 11/741,341
International Classification: A47C 7/02 (20060101);