GB2632827A

GB2632827A - Upholstered seat

Info

Publication number: GB2632827A
Application number: GB2312804.4A
Authority: GB
Inventors: Fitzsimmonds Nigel; Jones Mark
Original assignee: Equals42 Ltd
Current assignee: Equals42 Ltd
Priority date: 2023-08-22
Filing date: 2023-08-22
Publication date: 2025-02-26
Also published as: WO2025040913A1; GB202312804D0

Abstract

An upholstered seat, for example, for an office chair comprises a seat frame 12, seat padding 30, upholstery covering (14, Figure 1), and means for attaching the covering to the frame. The covering overlays the padding and frame and has a perimeter edge with a trim member 22 secured thereto. The lower surface of the frame includes a channel 20 shaped to receive the trim member. The covering comprises at least two parts 14’,14’’. The trim member has a U-shaped profile, comprising parallel first and second side walls 28’,28’’extending from a curved base portion. Each wall has a free edge. The trim member is fabricated from a resilient material, such that the free edges of the side walls are flexible. The free edge of the first trim member side wall is secured to the edge of the covering. The channel comprises a pair of parallel walls (32’,32’’; Figure 6b). The channel includes at least one trim securing element 26 in the form of a protrusion which engages with the free edge of the second wall of the trim member. In use, the trim member walls are in contact with, and in the same plane as, the channel walls.

Description

Upholstered Seat

Field of the Invention

The invention relates to the field of upholstery and in particular, to an upholstered seat, for example, an upholstered seat of an office chair.

Background of the Invention

Office chairs are typically covered by an upholstery covering which, for example, may be fabric, leather or mesh. The covering is usually attached to the chair frame using various techniques.

For a chair seat, padding or foam is usually present underneath the upholstery covering to provide added comfort or support. The upholstery covering improves the aesthetics of the seat but can also improve flammability resistance and also improves wear resistance. The upholstery covering is typically pulled taut over the frame and the foam padding, and then fastened directly to the underside of the seat frame using staples, or ultrasonic welding.

Another method of attachment of an upholstery covering to a chair frame includes a 'drawstring' process where a string is pre-sewn into a channel on the periphery of the covering and the ends of the string are then pulled together around the frame, and fastened on the underside of the seat frame by a combination of metal stapes and features within the seat frame. This form of attachment is regarded as being aesthetically unappealing.

These methods are time consuming and require additional tools or skills. Chairs upholstered using these known methods are also more difficult to re-upholster for re-use or to dis-assemble for recycling. Removal of metal staples is time consuming and not commercially viable.

US5195222 describes a fastening connection between a cushion covering and a vehicle seat frame. The fastening connection comprises a hook shaped profile strip located on the edge of the cushion cover, and a U-shaped edge channel on the seat frame. The channel includes projections for engaging with the hook shaped strip on the cushion cover, allowing the strip to snap into position within the channel. The hook shaped strip is V-shaped and is sufficiently elastic so that it can be pressed into the channel, but sufficiently rigid so that it does not deform to a large extent. The free end of the hook rests against the projections, and the hook lies at an angle within the channel. however, when a person sits on the seat of US5195222, the fabric cover is tensioned and the hook shaped strip is caused to rotate in a clockwise direction, away from the projections, meaning that the hook may be insecure and could disengage from the projections. Hence, this type of Fastening may be insecure as an upward force on the fabric causes rotation of the hook shaped strip, which tends to pull the strip out of the channel.

It would be desirable to provide an improved upholstery covering, with a more secure fastening means, which minimises the level of skill or craftsmanship required to achieve an improved end product.

Summary of the Invention

According to the invention, an upholstered seat comprises: a seat frame having an upper surface and a lower surface; seat padding located on the upper surface of the seat frame; an upholstery covering overlaying the scat padding and the seat frame, the upholstery covering having a perimeter edge; and means for attachment of the upholstery covering to the seat frame comprising: a tnm member secured to the upholstery covering, and a channel located on the lower surface of the seat frame, the channel shaped to receive the trim member; wherein the upholstery covering comprises at least two parts and is tailored to fir closely over the seat padding; wherein the trim member has a substantially U-shaped profile, comprising substantially parallel first and second side walls extending from a curved base portion, each wall having a free edge distal from the base portion; wherein the trim member is fabricated from a resilient material, such that the free edges of the side walls are flexible; and wherein the free edge of the first trim member side wall is secured to the perimeter edge of the upholstery covering; wherein the channel comprises a pair of spaced apart, substantially parallel walls, and the channel has a width and a depth, and the depth of the channel is larger than the width; wherein the channel includes at least one trim securing element in the form of a protrusion which, in use, engages with the free edge of the second arm of the trim member.

and wherein, in use, each of the walls of the trim member are in contact with, and in the same plane as, the walls of the channel.

Preferably, the upholstery covering comprises two parts which are sewn together forming a seam which extends around an outer edge of the seat padding. Preferably the seat padding further comprises a groove for eceiving the seam.

The channel may extend around the full perimeter of the seat frame, and the trim member may extend around the full perimeter edge of the upholstery covering The channel may be adjacent to a perimeter of the seat frame. Alternatively, the channel may be spaced apart from the perimeter of the seat frame, located further towards the centre of the seat frame.

Preferably, the depth of the channel is at least three times larger than the width.More preferably, the depth of the channel is at least four times larger than the width of the channel.

The free edge of the first trim ember side wall may be secured to the perimeter edge of the upholstery covering by a method selected from the following: sewing, adhesive, and ultrasonic welding.

The upholstery covering may be selected from the group comprising: fabric, leather,artificial leather, and mesh.

The or each trim securing element may have a first face which engages with the second trim member side wall as the trim is pushed into the channel and a second face which engages with the free edge of the second trim member side wall when said free edge of the second trim member side wall has passed beyond the first face of the trim securing element. The trim member is then located securely within the channel, and wherein the first face has a tapered profile.

The invention provides an improved upholstery covering, with secure fastening means. The process for covering the chair seat is deskilled and does not require tools yet achieves an improved end product.

Brief Description of the Drawings

In the Drawings, which illustrate preferred embodiments of the seat of the invention: Figure 1 illustrates an exploded view of an upholstered seat, viewed from above; Figure 2 illustrates an exploded view of the seat of Figure 1, viewed from underneath; Figure 3 illustrates an enlarged cross-sectional view of a part of the seat shown in Figure 1; I figure 4 illustrates an exploded cross-sectional view of the part of the seat shown in Figure 3; Figure 5 illustrates an assembled seat shown in Figure 1, viewed from underneath; Figure 6a illustrates a schematic cross-sectional view of an upholstery edge trim; Figure 6b illustrates a schematic cross-sectional view of the channel in the seat base frame; Figure Gc illustrates the upholstery edge trim of Figure 6a being inserted into the channel of Figure Gb; Figure 6d illustrates the upholstery edge trim of Figure 6a fully inserted into the channel of Figure GI); Figure 7a illustrates an underneath plan view of an upholstered seat, with channel adjacent to the perimeter of the seat frame; Figure 7h illustrates an underneath plan view of an upholstered seat, with channel inset from the perimeter of the scat frame; Figure 7c illustrates an underneath plan view of an upholstered seat, with channel further inset from the perimeter of the seat frame; Figure 8a illustrates a schematic partial cross-sectional view of a first stage of attaching an upholstery cover to form the seat of Figure 5; Figure 8b illustrates a schematic partial cross-secti ew of a second stage of attaching an upholstery cover to form the seat of Figure 5; Figure 8c is a cross-sectional view of a completed upholstered scat and Figure 9 is a schematic partial cross-sectional view of a completed seat, illustrating the forces acting on the trim member when the upholstery cover s under tension.

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Detailed Description of the Preferred Embodiments

Figure 1 illustrates an exploded view of a seat 10 for an office chair, viewed from above. The seat 10 comprises a base frame 12, seat padding 30, shown in the form of a foam cushion, and a fabric covering 14. The seat cushion 30 locates in-between the fabric covering 14 and the base frame 12. The fabric covering 14 may he any suitable fabric, including leather, artificial leather, and mesh. The fabric covering 14 comprises two parts 14' and 14" which are sewn together (the seam is illustrated by reference numeral 15) so that the shape of the fabric covering closely matches the size and shape of the foam cushion 30 so that it covers the seat frame and cushion rightly and without folds or puckers.

The base frame 12 is preferably fabricated from a moulded plastics material and comprises a number of strengthening ribs 16 and webbing 18 which stretch across the frame to support the seat cushion, and ultimately the user of the seat.

Figure 2 illustrates the seat 10 of Figure 1, viewed from underneath. The underside of the seat frame includes means for attachment to other chair parts which are not illustrated and do not form part of this disclosure, including leg assembly and a back assembly The underside of the seat frame also includes a channel 20, which in this example is located close to the perimeter of the underside of the seat frame. The channel 20 preferably extends all the way around the seat frame, as shown in Figure 2. The channel 20 forms a first part of an attachment means for attachment of the fabric covering 14 to the seat frame 12.

The fabric covering 14 has a perimeter edge 24 which is provided with a trim member 22 which forms a second part of the attachment means for securing the fabric covering 14 to the seat frame 12. This is shown in more detail in Figures 3 and 4. The channel 20 is shaped to receive the trim member 22 in order to secure the fabric covering 14 onto the seat frame 12.

Figure 3 illustrates an enlarged cross-sectional view of a part of the seat 10, with the trim member 22 secured within the channel 20. As shown this figure, the seat cushion 30 is located in between the seat frame 12 and the fabric covering 14. The seat cushion is preferably a foamed plastic material, such as polyurethane foam. The seat is shown upside down, with the underside of the seat frame uppermost in the drawing.

Figure 4 illustrates an exploded view of the part of the seat shown in Figure 3. The trim member 22 has a substantially U-shaped cross-section, comprising a pair of substantially parallel arms 28', 28" which meet at the base of the U-shape. The first arm 28' is secured to the edge 24 of the fabric covering 14. This could be achieved by sewing, adhesive, or nv other appropriate means. the second arm 28" is free.

The channel 20 includes a plurality of trim retaining elements, or protrusions 26, behind which the free end of the second arm 28" of the trim member locates, preventing withdrawal of the trim member 22, and fabric cover 14.

Preferably, as shown in Figure 4, the seat cushion 30 includes -a channel 25 which aligns with the seam 15 of fabric covering to help provide a smooth outer surface.

Figures 6a to 6d illustrate the process of insertion of the trim member 22 into the channel 20. The trim member 22 is fabricated from a material which is sufficiently resilient to allow insertion of the trim member 22 into the channel, but sufficiently rigid to allow easy insertion. As shown in Figure 6c, as the trim member s pushed into the channel 20, the second side arm 28" is elastically deflected towards the first side arm 28' as the trim member is pushed past the protrusion 26. As shown in Figure 6d, once past the protrusion, the second arm 28" returns to its original position and comes to rest behind the protrusion 26, securing the trim member 22 within the channel 20. Once inserted into the channel, both of the side arms 28', 28" of the trim member sit against the walls of the channel 20.

The protrusions 26 are preferably tapered on one side to aid insertion of the trim member. the tapered surface adjacent to the channel opening helps the second side arm 28" to ride over the protrusion. The protrusion is preferably flat on the side which faces away from the channel opening as this helps with engagement with the free end of the second side arm 28" of the trim member. When the fabric is put into tension, for example by a person sitting on the seat, the trim member s caused to rotate in a clockwise direction, as shown in Figure 9, forcing the free end of the second side arm 28" into engagement with the protrusion 26, providing a very secure attachment of the fabric covering 14 to the seat frame 12.

The channel width is narrow with respect to the channel depth. In the illustrated example the channel depth is four times its width.

The channel 20 includes a pair of substantially parallel walls; an outer wall 32' located adjacent the edge of the seat base frame 12 and an inner wall 32". In the example illustrated in Figures 6a to 6d the protrusions 26 extend from the inner wall 32" towards the outer wall 32'. The gap X between the end of the protrusion and the inner wall 32' is sufficient to allow the trim member 22 to be pushed through into the channel 20.

Figures 7a, 7h, and 7c illustrate different examples of seats in which location of the channel 22 s offset from the perimeter of the seat frame. As illustrated, the channel 22 can be offset from the perimeter towards the centre of the seat if desired, with the size of the second part of the &brie cover 14" adjusted accordingly In Figure 7c it can be seen that the second part of the fabric cover 14" is comprised of four pieces of fabric 14a sewn together along scams 14b.

Figures 8a, 81), and 8c illustrate the process of upholstering eat.

As shown in Figure 8a, the seat frame 12 is provided with a foam cushion 30 and a tailored fabric cover 14 is placed loosely over the cushion 30 and aligned therewith. As shown in Figure 8b, the foam cushion 30 is then compressed (as illustrated by the bottom arrows), allowing the trim member 22 to be pressed vertically into the channel 20 on the seat frame 12. Figure 8c illustrates the completed upholstered seat. Once the foam cushion expands the fabric cover 14 is pulled taut over the foam cushion 30.

Figure 9 illustrates how, when the fabric is put into tension, for example by a person sitting on the sear, the trim member is caused to rotate in a clockwise direction, forcing the free end of the second side arm 28" into engagement with the protrusion 26, providing a very secure attachment of the fabric covering 14 to the scat frame 12.

The sear frame has a perimeter face 12a having a lower perimeter edge 12a'. It can he seen that the scat cushion 30 extends both beyond the perimeter face 12a and below the lower perimeter edge 12a. This arrangement of the seat cushion 30 relative to the perimeter of the scat frame 12 ensures that the resulting upholstered seat is aesthetically pleasing The attachment arrangement, and two-part fabric cover of the invention allows the upholstery cover to be stretched tightly over the seat cushion 30 without any folds or puckering. The trim member is preferably continuous around the edge of the fabric cover, so the end product has a very neat finish, as illustrated in Figures 5 and 7, and the cover is held very securely on the frame.

Claims

Claims 1. An upholstered scat comprising: a seat frame having an upper surface and a lower surface; seat padding located on the upper surface of the seat frame; an upholstery covering overlaying the scat padding and the scat frame, the upholstery covering having a perimeter edge; and means for attachment of the upholstery covering to the seat frame comprising: a trim member secured to the perimeter edge of upholstery covering, and a channel located on the lower surface of the seat frame, the channel shaped to receive the trim member; wherein the upholstery covering comprises at least two parts and is tailored to fit closely over the seat padding; wherein the trim member has a substantially U-shaped profile, comprising substantially parallel first and second side walls extending from a curved base portion, each wall having a free edge distal from the base portion; wherein the trim member is fabricated from a resilient material, such that the free edges of the side walls are flexible; and wherein the free edge of the first trim member side wall is secured to the perimeter edge of the upholstery covering; wherein the channel comprises a pair of spaced apart, substantially parallel walls, and the channel has a width and a depth, and the depth of the channel is larger than the width; wherein the channel includes at least one trim securing element n the form of a protrusion which, in use, engages with the free edge of the second arm of the trim member.and wherein, in use, each of the walls of the trim member are in contact with, and in the same plane as, the walls of the channel.
2. An upholstered seat according to Claim 1, wherein the at least two parts of the upholstery covering are joined by a sewn seam.
3. An upholstered according to Claim 1 or 2, wherein one or more of the at least two parts is formed from a plurality of pieces joined together.
4. An upholstered seat according to Claim 2 or 3, wherein the seat padding Further comprises a groove for receiving the sewn seam of the covering.
5. An upholstered seat according to any preceding claim, wherein the seat frame has a Pe meter and the channel extends around the perimeter of the seat frame.
6. An upholstered seat according to any of claims 1 to 4, wherein the seat frame has a Pe meter and the channel is spaced apart from the perimeter of the seat frame.
7. An upholstered seat according to any preceding,wherein the depth of the channel is at least three times larger than the width.
8. An upholstered seat according to Claim 7, wherein the depth of the channel is at least four times larger than the width of the channel.
9. An upholstered seat according to any preceding claim, wherein the free edge of the first trim member side wall is secured to the perimeter edge of the upholstery covering by a sewn seam, an adhesive, or an ultrasonic weld.
10. An upholstered seat according to any preceding claim, wherein the upholstery covering is selected from the group comprising: fabric, leather, artificial leather, and mesh.
11. An upholstered seat according to any preceding claim, wherein the or each trim securing element has a first face which engages with the free edge of the wall as the trim is pushed into the channel and a second face which engages with the free edge of the second trim member side wall when the trim member s located within the channel, and wherein the first face has a tapered profile.
12. An upholstered seat according to any preceding claim, wherein the seat padding extends beyond the perimeter of the seat frame.
13. An upholstered seat according to Claim 12, wherein the seat padding extends beyond the perimeter of the scat frame and below a lower perimeter edge of the scat frame.
14. A chair comprising an upholstered seat as claimed in any of Claims 1 to 13. 13. A chair according to Claim 14, wherein the chair is an office chair.