GB2621574A

GB2621574A - Heated sofa

Info

Publication number: GB2621574A
Application number: GB2211873.1A
Authority: GB
Inventors: Vaughan Paul
Original assignee: Dfs Trading Ltd
Current assignee: Dfs Trading Ltd
Priority date: 2022-08-15
Filing date: 2022-08-15
Publication date: 2024-02-21
Also published as: GB202211873D0

Abstract

A heated sofa (10, Figure 1) comprising a frame 11 having a seat support portion 12 and a lumbar support portion 13. The sofa further comprises at least one seat cushion 15 mountable at the seat support portion and having an external facing seating surface 18 defined by a cushion outer cover (41, Figure 3) on which a user is capable of seating and an opposite support surface 20 positionable against the seat support portion to mount the cushion to the sofa. A seat heater 24a is incorporated with the seat cushion and has a heating surface (24c, Figure 3) from which heat energy may be emitted. The heater is positioned within the seat cushion closer to the seating surface relative to the support surface in a thickness direction of the cushion; and the seat cushion comprises a thermal transfer layer positioned intermediate the heating surface of the heater and the seating surface of the cushion. The seat cushion may comprise a foam underlayer/substrate 26 positioned at an opposite side of the heater relative to the thermal transfer layer. The cushion may comprise an internal spring arrangement 28 comprising coil springs 29.

Description

Heated Sofa

Field of invention

The present invention relates to a sofa and in particular, although not exclusively, to a 20 heated sofa having cushions configured with heating elements.

Background

Heated seats and heated cushions have been developed for different seating types including vehicle seats, luxury domestic seating, stadium seating, medical devices etc. The heat energy is typically provided by passing a current through resistance heating wires extending within the seat or cushion An example heated vehicle seat is described in WO 2014/115212 Al Domestic sofas have also been developed with heating elements as described in ON216293561U; CN211673371U; ON110840149A; CN202619001U; and CN208957338U.

However, sofas and domestic chairs are typically designed for user comfort as well as providing sufficient support at various regions such as the upper leg and lumbar spine. Domestic sofas are also required for longevity and to withstand many years of user loading. Accordingly, positioning heating elements within a sofa and in particular within sofa cushions, involve many considerations. Existing heated sofa arrangements arc disadvantageous for a number of reasons. Whilst providing effective heating, for example, a heating element at the cushion can be positioned too close to the seating or lumbar support surfaces which is uncomfortable when felt by a user. Conversely, a heating element positioned too far from the seating or lumbar surfaces may not provide efficient and effective heating at the user contact surfaces of the cushions. Further considerations include safety and sofa longevity including ease of maintenance of the sofa and electrically powered heating elements. Accordingly, what is required is a heated sofa that addresses the above problems.

Summary of the Invention

The inventors provide a heated sofa configured with effective and efficient heating at various regions of the sofa including the seating surface (at the generally horizontal seat cushions) and lumbar support surface (of the inclined or more upright lumbar cushions). In particular, the inventors provide a heated sofa that a balance between efficient/effective heating and desired levels of user comfort. Additionally, the present sofa is further configured for longevity and to exhibit fatigue resistance due to repeated user loading (a user sitting into and standing-up from the sofa). The present sofa configuration is further designed for ease of maintenance by offering convenient access to the heating elements mounted internally within at least the seat cushion(s) and optionally the back or lumbar cushion(s) The present concept is suitable for both static and adjustable sofas such as motion sofas, recliners and the like According to a first aspect of the present concept there is provided a sofa comprising: a frame having a seat support portion and a lumbar support portion; at least one seat cushion mountable at the seat support portion and having an external facing seating surface defined by a cushion outer cover on which a user is capable of seating and an opposite support surface positionable against the seat support portion to mount the cushion at the sofa; a seat heater incorporated with the seat cushion and having a heating surface from which heat energy may be emitted; wherein: the heater is positioned within the seat cushion closer to the seating surface relative to the support surface in a thickness direction of the cushion; and the scat cushion comprises a thermal transfer layer positioned intermediate the heating surface of the heater and the seating surface of the cushion.

The present sofa achieves the desired balance between comfort and efficient and effective 10 heating via i) the relative positioning of the heater at the cushion being closer to the seating surface relative to the opposite support surface and ii) the intermediate thermal transfer layer extending between the outer cover and the heater.

Optionally, the seat cushion of the sofa may comprise a spring arrangement with the heater mounted above or on top of the spring arrangement Optionally, the seat cushion may not comprise a spring arrangement and the main body of the cushion may comprise one or a plurality of layers of foam positioned below or underneath the heater and at an opposite side of the heater relative to the thermal transfer layer.

Optionally, the seat cushion and/or lumbar cushion may comprise additional thermal insulating layers positioned below or adjacent the heater. Such an arrangement may be advantageous to avoid dissipation of heat energy into the underlying cushion material or components and direct heat energy upwardly/forward to a user and not downward/rearward into the sofa.

Preferably, the seat cushion further comprises a foam underlayer or substrate positioned at an opposite side of the heater relative to the thermal transfer layer. Preferably, the seat cushion further comprises an internal spring arrangement extending between the support surface and the foam underlayer. Preferably, the spring arrangement comprises a plurality of coil springs extending between a base pad/board and an upper pad/board, the upper pad/board positioned adjacent the foam underlayer.

Advantageously, a foam underlayer or substrate on which the heater is supported further enhances the comfort so as to provide a degree of compression and load bearing under the heater. The positioning of the foam underlayer or substrate below the heater (or at a rearward side of the heater relative to the external facing surface of the cushion) achieves 5 the desired comfort without compromising heating efficiency. It has been noted by the inventors that foam materials whilst enhancing comfort, arc effective to absorb heat energy which reduces heating efficiency and effectiveness. Accordingly and preferably, the present sofa and in particular sofa cushions do not comprise a foam material or foam layer positioned between the heater and the external facing seating surface and/or lumbar 10 surface.

Optionally, a thickness of the foam underlayer is in a range 15 to 50 mm, 20 to 45 mm, 25 to 40 mm, 25 to 35mm or 30 to 40 mm. Such an arrangement is beneficial to achieve the desired level of comfort without providing an appreciable mass of foam material that may 15 absorb heat energy.

Optionally, in a general plane of the seating surface, a seating area coverage by which the heater extends adjacent the seating surface is in a range 20 to 90%, 20 to 80%, 20 to 70%, 25 to 65%, 40 to 70%, or 25 to 45% of the total seating area of the seating surface of the at least one seat cushion. Optionally, in a general plane of the lumbar surface, a lumbar area coverage by which the heater extends adjacent the lumbar support surface is in a range 20 to 90%, 20 to 80%, 20 to 70%, 30 to 50%, 25 to 45%, or 20 to 40% of the total seating area of the seating surface of the at least one seat cushion The present sofa therefore provides an extensive surface area for sitting and lumbar support that is heated. A perimeter boarder of the seating and lumbar surfaces may not be heated as typically these regions would not be contacted by a user sitting on the sofa and may be difficulty to service and may be susceptible to damage. Accordingly, this arrangement provides an efficient heating arrangement and avoids heating unnecessary sofa regions which would be energy inefficient/wasteful.

Preferably, the sofa further comprises a lumbar cushion mountable at the lumbar support portion and having an external facing lumbar surface defined by a cushion outer cover and an opposite support surface positionable against the lumbar support portion of the frame. Preferably, the lumbar cushion comprises a lumbar heater having a heating surface from which heat energy may be emitted, the heater positioned within the cushion closer to the lumbar surface relative to the support surface in a thickness direction of the cushion.

Preferably, the lumbar cushion further comprises a thermal transfer layer positioned intermediate thc heating surface of thc heater and the lumbar surface. Optionally, thc lumbar cushion comprises a foam substrate positioned at an opposite side of the heater relative to the thermal transfer layer.

Optionally, a thickness of the thermal transfer layer is in a range 15 to 50 mm, 20 to 45 mm, 25 to 40 mm, 25 to 35mm or 30 to 40 mm. Such a thickness is advantageous to provide the desired comfort without compromise of heating efficiency/effectiveness. In particular, when energised, it is preferred that a heating effect is felt by a user within a few minutes and that this heat energy is concentrated and focussed towards the user and not downwardly or rearwardly into the sofa. An intermediate transfer thermal transfer layer being too thick, would provide inefficient heating and an undesirable time delay in the transfer of heat energy from the heater to the user.

Optionally, the thermal transfer layer comprises a fibre material. Optionally, the fibre material may comprise polyester. Optionally, the fibre material may comprise any one or a combination of a natural material, a synthetic material, wool, mohair, lamb hair, a hybrid natural-synthetic material. Optionally, the fibre material may comprise any one or a combination of organic or recycled cotton, natural hemp, tencel, organic linen, nylon, polypropylene, a viscose, a cellulose-based material, a natural or synthetic polyester, a biodegradable material.

Optionally, the outer cover of the seat and/or lumbar cushion may comprise leather, faux leather, a fabric, a textile, a woven textile or fabric.

Preferably, the heater comprises a resistance wire contained within a pocket or covering. Preferably, the pocket or covering comprises a textile material. Optionally, the heater is a heating pad or heating blanket having an internal resistance heating wire.

Preferably, the sofa comprises electrical connections for connection to an electrical power supply. Preferably, the sofa comprises a suitable control module to control the current and/or voltage supplied to the heater(s). Preferably, the electrical connections and control module are mounted at least partially internally within sofa body at the frame. Optionally, thc control module may comprise any one or combination of dials, buttons, a uscr interface, a display interface, etc. Optionally, the control module may comprise wired or wireless communication modules for communication with a local network and/or the internet.

Brief description of drawings

A specific implementation of the present invention will now be described, by way of example only, and with reference to the accompanying drawings in which Figure 1 is an external perspective view of a heated sofa according to a specific implementation of the present concept; Figure 2 is a cross sectional side view through A-A of figure 1 according to the specific 20 implementation, Figure 3 is an exploded and magnified view of the heater and adjacent layers of the seat cushion of the sofa of figures 1 and 2 according to the specific implementation, Figure 4 is a rear perspective view of the seat cushion of figure 2 illustrating a dual-layer and closure arrangement at the rear/back face of the cushion according to the specific implementation Detailed description of preferred embodiment of the invention Referring to figure 1 a sofa 10 comprises a frame 11 typically formed from a wood-based material or construct Frame 11 comprises a seat support portion 12 and a lumbar support portion 13 configured to support a plurality of seat cushions 15 and a plurality of lumbar cushions 16, respectively. Frame 11 further comprises arm rests 14 and feet 17 extending between frame 11 and a floor surface Referring to figure 2, frame 11 and in particular seat support portion 12 comprises a seat cushion support surface 22. Similarly, frame 11 at lumbar support portion 13 comprises a lumbar cushion support surface 23. Surface 22 is generally aligned to be horizontal whilst surface 23 is inclined relative to surface 22 to support the inclined lumbar cushions 16. According to the present configuration, each cushion 15, 16 comprises a respective heater including specifically a seat heater 24a (incorporated within the seat cushion 15) and a lumbar heater 24b (incorporated within each lumbar cushion 16). Each heater 24a, 24b is connected via suitable electrical connections to an electrical power supply 32 which is, in turn, provided in electronic communication with a suitable control module 33. Both components 32, 33 are mounted at least partially internally within sofa body at frame 11.

Control 33 may comprise dials, a user interface, a display interface, buttons etc. Optionally, control 33 may comprise wired or wireless communication modules for communication with a local network and/or the internet. Optionally, control module 32 may be connectable to a portable handheld electronic device such as a smart phone or tablet to provide control of heaters 24a, 24b via a local user interface (smart phone or

tablet).

Lumbar cushion 16 comprises an external facing lumbar surface 19 and rearward and opposite support surface 21 positionable against support surface 23 of lumbar support portion 13. Similarly, seat cushion 15 comprises an external facing seating surface 18 and an opposed and downward facing support surface 20 for positioning opposed to the generally upward facing support surface 22 of seat support portion 12. According to the present concept, each respective heater 24a, 24b is positioned closer to the user contact surfaces, being seating surface 18 and lumbar surface 19 relative to the respective rearward facing support surfaces 20, 21. According to the preferred configuration, each heater 24a, 24b is positioned in the range 5 to 25%, 5 to 20%, 5 to 15% or 5 to 10% of the cushion closest to the respective seating surface 18 and lumbar surface 19 relative to a full depth or thickness of each respective cushion 15, 16, where such a depth or thickness is defined as the maximum distance between surfaces 18 and 20 and the respective surfaces 19 and 21.

Each heater 24a, 24b comprises resistance wiring connected to power supply 32 via a suitable electrical connection. Heating wires are contained within an enclosure preferably a fabric or textile enclosure to define a heating pad, blanket or layer extending underneath and adjacent each respective surface 18, 19 of each cushion 15, 16. Referring to figure 4, heater 24a, in a general plane of surface 18, heater 24a extends adjacent the majority of the surface area of surface 18 safe for a permitter boarder 40 within which heater 24a does not extends. According to a preferred implementation, at least seat heater 24a extends adjacent surface 18 in a range 20 to 70% of the total seating area surface 18 of each respective cushion 15. A similar arrangement and configuration may apply to lumbar cushion 16 with regard to surface 19 and lumbar heater 24b.

Referring again to figure 2, each cushion 15, 16 further comprises a thermal transfer layer 25 positioned intermediate surface 18 and each respective heater 24a, 24b. According to preferred embodiment, each seat cushion 15 comprises a spring arrangement 28 provided with a plurality of coil springs 29 that extend axially between an upper plate or board 27 and a lower or rearward support plate or board 30 (positioned immediately adjacent the rearward facing cushion support surface 20) At least one foam surround block or assembly 31 extends around the spring arrangement 28 and fills the remaining internal volume of the cushion 15 as defined between surfaces 18 and 20 and the respective four side wall surfaces (cushion front, rear and lateral sides).

A foam support layer 26 extends between upper pad/board 27 and heater 24a. An exploded magnified view of the multilayer heater arrangement of figure 2 is described and illustrated referring to figure 3. Tn the preferred embodiment, a thickness of the thermal transfer layer 25 is in the region 25 to 35 mm. Similarly, a foam support layer 26 that is positioned underlying heater 24a and intermediate heater 24a and board 27 comprises a thickness in a range 25 to 35 mm. Such a configuration is advantageous to provide a desired balance of comfort to a user sitting on the sofa 10 and effective and efficient heat transfer from heater 24a to the user via surface 18.

According to the specific embodiment, thermal transfer layer 25 comprises a fibrous material that has been found to be effective to offer sufficient cushioning at the position immediately above heater 24a whilst allowing effective and efficient heat energy transfer from a heat emitting surface 24c of heater 24a. The underlying foam layer 26 works synergistically with the upper fibrous layer 25 to provide suitable cushioning for improved comfort. The thickness of foam layer 26 is provided at the respective size so avoid appreciable heat energy being absorbed and directed downwardly and internally into cushion 15. Such an arrangement would otherwise appreciably increase the initial heating time (by which the heater is activated and heats to the desired maximum heating temperature) and reduce overall heating efficiency.

Referring to figure 2 and as indicated, each lumbar cushion 16 comprises a heater 24b and respective thermal transfer layer 25. However, in contrast to seat cushions 15, lumbar cushions 16 comprise a main body foam underlayer 36 that extends rearwardly from heater 24b to the rearward facing support surface 21. This underlayer 36 represents the majority vol% filling component of the lumbar cushion 16. Such a configuration is advantageous in response to the loading applied to the cushion 16 by a user sitting on the sofa 10 relative to the larger loading applied to seat cushion 15 (due to the relative orientations of the cushions 15, 16 and gravity). According to further embodiments, each seat cushion 15 may comprise a main body (by internal vol% of the cushion) foam underlayer and not the respective spring arrangement 28. Equally, each lumbar cushion 16 may comprise a spring arrangement and not a main body foam underlayer 36. However, it is noted that spring arrangement 28 at the seat cushion 15 is advantageous for efficient and effective heating as any heat energy absorbed by the cushion materials underlaying the heater, is minimised due to the void/cavity region immediately surrounding the springs 29.

Referring to figures 2 to 4, each cushion 15, 16 is defined externally by a cover layer 41 that encapsulates internal layers and components 25, 24a, 24b, 26, 28, 36 as appropriate.

Cover layer 41 may comprise leather, faux leather or a textile material. Referring to figure 4, each cushion 15, 16 comprises an end face 35 that is upholstered. That is, an upholstered layer 42 is overlaid onto outer cover layer 41 via respective perimeter seams (not shown) Upholstered layer 42 comprises an opening defined by a hook and loop type strip 34 having a respective hook strip 38 and an opposed loop strip 37 that interengage one another via frictional contact A second opening is provided at cover layer 41 and defined by a zip 39. Accordingly, access to the interior cavity of each cushion 15, 16 is achieved via the respective duel opening of the hook and loop strip 34 (at layer 42) and the zip 39 (at layer 41). Such an arrangement is beneficial to gain access into the cushion interior and optionally removed each respective heater 24a, 24b and/or to provide servicing maintenance, etc.

Claims

Claims 1. A sofa comprising: a frame having a seat support portion and a lumbar support portion; at least one seat cushion mountable at the seat support portion and having an external facing seating surface defined by a cushion outer cover on which a user is capable of seating and an opposite support surface positionable against the seat support portion to mount the cushion at the sofa; a seat heater incorporated with the seat cushion and having a heating surface from 10 which heat energy may be emitted; wherein: the heater is positioned within the seat cushion closer to the seating surface relative to the support surface in a thickness direction of the cushion; and the seat cushion comprises a thermal transfer layer positioned intermediate the 15 heating surface of the heater and the seating surface of the cushion.
2. The sofa as claimed in claim 1 wherein the seat cushion further comprises a foam underlayer or substrate positioned at an opposite side of the heater relative to the thermal transfer layer.
3. The sofa as claimed in claim 2 wherein the seat cushion further comprises an internal spring arrangement extending between the support surface and the foam underlayer.
4. The sofa as claimed in claim 3 wherein the spring arrangement comprises a plurality of coil springs extending between a base pad/board and an upper pad/board, the upper pad/board positioned adjacent the foam underlayer.
5. The sofa as claimed in any one of claims 2 to 4 wherein a thickness of the foam underlayer is in a range 15 to 50 mm, 20 to 45 mm, 25 to 40 mm, 25 to 35mm or 30 to 40 mm.
6. The sofa as claimed in any preceding claim wherein in a general plane of the seating surface, a seating area coverage by which the heater extends adjacent the seating surface is in a range 20 to 90%, 20 to 80%, 20 to 70%, 25 to 65%, 40 to 70%, or 25 to 45% of the total seating area of the seating surface of the at least one seat cushion.
7. The sofa as claimed in any preceding claim further comprising a lumbar cushion mountable at the lumbar support portion and having an external facing lumbar surface defined by a cushion outer cover and an opposite support surface positionable against the lumbar support portion.
8. The sofa as claimed in claim 7 wherein the lumbar cushion comprises a lumbar heater having a heating surface from which heat energy may be emitted from the heater, the heater positioned within the cushion closer to the lumbar surface relative to the support surface.
9. The sofa as claimed in claim 8 wherein the lumbar cushion further comprises a thermal transfer layer positioned intermediate the heating surface of the heater and the lumbar surface.
10. The sofa as claimed in any preceding claim wherein a thickness of the thermal transfer layer is in a range 15 to 50 mm, 20 to 45 mm, 25 to 40 mm, 25 to 35mm or 30 to 40 mm.
11. The sofa as claimed in any preceding claim wherein the thermal transfer layer 25 comprises a fibre material.
12. The sofa as claimed in claim 11 wherein the fibre material comprises polyester.
13. The sofa as claimed in claim 11 wherein the fibre material comprises any one or a 30 combination of a natural material, a synthetic material, wool, mohair, lamb hair, a hybrid natural-synthetic material.
14. The sofa as claimed in any preceding claim wherein the heater comprises a resistance wire contained within a pocket or covering
15. The sofa as claimed in claim 14 wherein the pocket or covering comprises a textile material.
16. The sofa as claimed in any one of claims Ito 13 wherein the heater is a heating pad or heating blanket having an internal resistance heating wire.
17. The sofa as claimed in any preceding claim when dependent on claim 9 wherein the lumbar cushion comprises a foam substrate positioned at an opposite side of the heater relative to the thermal transfer layer.