AU2014101331A4 - Bedding foundation spring module, and method of assembling a bedding foundation incorprating the modules - Google Patents

Abstract

A spring steel module for a bedding foundation, operable to support the top grid above the base frame of the bedding foundation, has a 5 substantially Z-shaped foot securable to a timber slat of the base frame, a pair of inclined legs at the ends of the foot, and grid support members at the upper ends of the legs. Each grid support member is substantially U shape in plan view and is operable to support, and secure together, a line wire overlying a cross wire of the top grid at a joint, where the cross wire is 10 supported by a pair of spaced cradles, and an arch portion of the grid support member, which interconnects the pair of cradles, overlies the line wire and clamps the line wire and cross wire together. A method of manufacturing a bedding foundation, employing a plurality of the modules, is also described. 2118496v1 -<'NZ

Description

1 TITLE: BEDDING FOUNDATION SPRING MODULE, AND METHOD OF ASSEMBLING A BEDDING FOUNDATION INCORPRATING THE MODULES 5 BACKGROUND OF THE INVENTION: 1. Field of the Invention: [0001] This invention relates to a bedding foundation spring module, and to a method of making a bedding foundation employing such modules. 10 [0002] The invention particularly relates, but is not limited to, a method of linking the wires of a top surface grid of a bedding foundation employing a plurality of the spring modules which also provide legs for the foundation frame 15 2. Prior art: [0003] NB: The following discussion is by way of background information only, and is not to be considered a statement of the common general knowledge (CGK) in the area of technology. [0004] The top platform of bedding foundations offers uniform support for the 20 mattress placed thereon.. [0005] Many manufacturers use a welded wire grid or a fabricated timber slat frame. Plain steel wire is prone to plastic deformation; while timber is heavy, expensive and forms a rigid structure. [0006] Sealy@ bedding foundations consist of a timber base frame, a wire 25 grid forming the top surface, and numerous modules which connect the two and dictate the profile height of the foundation. Spring steel wire is used due to its greater resistance to permanent deformation. [0007] Spring wire is difficult to weld; and its properties are compromised by the heat in the welding process. This means that the crossover joints of the 30 wire top grid are not physically connected. [0008] The height of the bedding foundation is determined by a series of wire 'modules', which have several functions: 2118496v1 2 a) Clamp the loose crossover joints of the top grid firmly enough to prevent movement which can cause undesirable noises in the finished foundation. b) Elevate the top grid on a series of wire legs to form the height of the foundation; and 5 c) Provide a means of stapling the wire structure to the timber base frame. OBJECTS OF THE INVENTION: [0009] It is an object of the present invention to provide a bedding foundation spring module which overcomes, or at least ameliorates, the 10 problems with existing bedding foundations. [0010] Other preferred objects of the present invention will become apparent from the following description. SUMMARY OF THE INVENTION: 15 [0011] In one aspect, the present invention resides in a bedding foundation spring module, having an elongate body formed of spring steel or like material, including: a foot securable to a base frame of a bedding foundation; a respective upstanding leg at each end of the foot; and 20 a grid support member at an upper end of each leg; each grid support member being of substantially U-shape in plan, with a pair of spaced cradle portions, each cradle being defined by a pair of spaced shoulders; each grid support member being arranged to receive and engage a cross 25 wire and a line wire at a joint in a top grid of a bedding foundation frame. [0012] Preferably, each grid support member has an arch portion, interconnecting the pair of cradle portions, and operable to pass over the upper of the line wire or the cross wire at the joint and restrain the wires at the joint. 30 [0013] Preferably, the foot is of substantially Z-shape in top plan view, with an intermediate portion securable to the base frame by fasteners e.g. staples or nails. 2118496v1 3 [0014] Preferably, the legs extend upwardly from distal ends of end portions of the foot; and at least one of the legs is inclined to the vertical z-axis, along the horizontal y-axis, when in use, so that the cradle portions are substantially 5 aligned with the intermediate portion of the foot, and the module forms a substantially triangulated support for the joint.. [0015] Preferably, the legs are oppositely inclined to the z-axis on the horizontal x-axis.. [0016] preferably, the respective grid support members are oppositely 10 directed relative to their respective legs, and overlie the respective end portions of the foot. [0017] Preferably, each grid support member has a proximal end, connected to the respective leg, forming one of the pair of shoulders of one of the cradle portions; and a distal end, forming one of the pair of 15 shoulders of the other cradle portion, and terminating in a downwardly directed tail. [0018] Preferably, the arch portion of each grid support member provides the other of the pair of shoulders for both cradle portions. [0019] In a second aspect, the present invention resides in a method of 20 assembling a frame for a bedding foundation, including the steps of: a) forming a base frame for a bedding foundation, the base frame having a plurality of slats; b) forming a top grid of a regular lattice of spaced line wires intersected by spaced cross wires at respective joints in the top grid; 25 c) engaging a respective arch portion of each grid support member of a module, hereinbefore described over the respective line or cross wires at an adjacent pair of joints in the top grid, with the module extending substantially horizontally; d) hingedly moving the module downwardly towards a substantially 30 vertical position, to cause the cross or line wire interconnecting the line or cross wires, to be received in, and engaged by, each pair of spaced cradles of each grid support member at each joint; and 2118496v1 4 e) securing the foot of the module to a slat of the base frame; and f) repeating steps c) to e) until all joints in the top grid are supported above the base frame by a plurality of the modules. [0020] Preferably, in step b), at each joint, each cross wire has a single 5 dimple or depression; and is overlaid by a transverse line wire which has a pair of spaced dimples or depressions interconnected by an arch portion receivable in the dimple or depression of the cross wire, the spaced pair of dimples or depressions on the line wire forming abutment stops to locate the line wire to the cross wire. 10 [0021] Preferably, in step a),the slats of the base frame are formed of timber; and In step e), the foot of each module is secured to a respective slat by one or more staple(s), nails or clips driven into the slat. 15 [0022] Other preferred aspect of the present invention will become apparent from the following description; and shall include .a bedding foundation having a foundation frame incorporating a plurality of the spring modules and the foundation frame assembled by the method. 20 BRIEF DESCRIPTION OF THE DRAWINGS: [0023] To enable the invention to be fully understood, and to enable the skilled addressee to put the invention into practice, a number of preferred embodiments will now be described, with reference to the accompanying illustrations, in which: 25 FIG. 1 is an isometric view of a bedding foundation spring module in accordance with a first embodiment of the invention; FIGS. 2 to 4 are respective top plan, front elevational and side elevational views of the module; FIG. 5 is an isometric view of the module supporting the wires of the top 30 grid of the foundation frame; FIGS. 6 to 8 are respective isometric views of the method of assembling the foundation frame using a module; 2118496v1 5 FIG. 9 is an isometric view of the line and cross wires at a joint on the top grid; FIG. 10 is an isometric view of a foundation frame assembled using a plurality of the modules; 5 FIG. 11 is an exploded view of FIG. 10; and FIGS. 12 and 13 are respective side and end elevation views of the frame of FIG. 10 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS: 10 [0024] Referring to FIGS. 1 to 4, the bedding foundation spring module 10 is to be employed in the manufacture of a bedding foundation 20, having a foundation frame 21 as illustrated in FIGS. 10 to 13. (The fabric covering for the bedding foundation 20 has been omitted for clarity. [0025]) The foundation frame 21 is rectangular in top plan view, with a 15 base frame 22 defined by side rails 23 interconnected by end rails 24 and a plurality of equally spaced slats 25. The rails 23, 24 and slats 25 are formed from suitable timber(s). [0026] A top grid 30 is supported above the base frame 21 by a plurality of the modules 10 to be hereinafter described in more detail. The top grid 30 20 is provided in the form of a (substantially planar) rectangular lattice comprising longitudinally-extending line wires 31 and laterally-extending cross wires 32, which intersect at equally spaced joints 33. The wires 31, 32 are formed from suitable gauge / strength spring steel for the intended load the foundation 20 is to support. 25 [0027] As best illustrated in FIG. 9, a line wire 31 overlies a cross wire 32 at each joint 33; and the wires 31, 32 are locked together by the module 10 (and by the respective features of the wires 31, 32 to be hereinafter described). The resultant structure of the top grid 30 resists relative movement of the wires 31, 32; and is so resistant to bending or distortion 30 on all 3 axes. [0028] At regularly spaced intervals, corresponding to the distance between joints 33, each cross wire 32 has a dimple or depression 35, 2118496v1 6 which can receive the overlying line wire 31. [0029] At regularly spaced intervals, also corresponding to the distance between adjacent joints 33, each line wire 31 has a pair of spaced dimples or depressions 36, 37; the pair of depressions 36, 37 being 5 interconnected by an arch portion 38. The arch portion 38 is operable to be received in the depression 35 in the cross wire, and is defined by a pair of abutment faces 39, 40, which operate to laterally locate the wires 31, 32, at the joint 33, in the horizontal plane i.e. in the x- and y- axes. [0030] Each wire module 10 is also formed from suitable gauge / strength 10 spring steel, cut to length and bent or otherwise formed to the desired shape. [0031] The module 10 has a foot 50, to be secured to one of the slats 25, by staples 26 (or other suitable fasteners or clips securable to the slat 25.) The foot 50 is substantially Z-shaped in top plan view, with an 15 intermediate foot portion 51 interconnecting oppositely- directed end portions 52, 53. [0032] A respective leg 54, 55 extends upwardly from the distal ends of the end portions 52, 53. Leg 54, 55 is inclined to the vertical z-axis in the x-axis, but is substantially vertical in the y-axis. Leg 55 is inclined to the 20 vertical z-axis in both the horizontal x- and y-axes, as best illustrated in FIGS. 2 and 4, to provide a triangulated support for the top grid 30 at each joint 33. This provides very good lateral stability in both the x- and y- axes (and also resists compression of the module 10 in the z-axis when a load is applied to the top grid 30). NB: The horizontal x-axis is taken to lie 25 along the longitudinal axis of the intermediate foot portion 51 (and the corresponding axes of the timber slat 25 and of the cross wire 32 at joint 33); and the horizontal y-axis is considered to be transverse to the x-axis (i.e. parallel to the longitudinal axis of the line wire 31 at the joint 33.) [0033} A respective grid support member 60, 61 is provided at the upper 30 end of the legs 54, 55. [0034] As the grid support members 60, 61 are substantially mirror images, only the features (xx) of grid support member 60 will be 2118496v1 7 described, while on the drawings, the equivalent features will be identified by a reference numeral (xxA) i.e. feature 65 on grid support member 60 = feature 65A on grid support member 61. [0035] The grid support member 60 is substantially U-shaped in top plan 5 view, as illustrated in FIG. 2, and has a proximal end 62, connected to the upper end of leg 54, which forms the first of a pair of shoulders 63, 64, interconnected by a cradle portion 65 aligned with the x-axis. [0036] A similar cradle portion 66 interconnects a pair of shoulders 67, 68, the latter adjacent a downwardly-inclined tail 69 at the distal end of the 10 grid support member 60. The cradle portions 65, 66 are operable to support a cross wire 32 laid across the grid support member 60. [0037] The respective shoulders 64, 67 are interconnected by an arch portion 70, which is curved in top plan view, and which has an inner (lower) engagement face 71 operable to engage the line wire 31. The 15 vertical distance between the inner face 71, and the cradle portions 65, 66 is not greater than, and more preferably just less than, the combined thicknesses of the cross wire 32 and overlaid line 31, at a joint 33, to securely clamp the wires 31, 32 together at the joint 33. [0038] The resilience of the spring steel, forming the spring module 10, 20 will enable the grid support members 60, 61 to flex as the grid support members engage, and secure, the wires 31, 32 at each joint; while the tension within the spring steel will cause each grid support member 60, 61 to securely clamp the wires 31, 32 together at the joint 33. [0039] The method of assembling the foundation frame 21, incorporating 25 a plurality of the spring modules 10, will now be described with reference to FIGS. 6, 7, 8 & 5, which illustrate the progressive steps of the method. [0040] The foundation frame 21 is assembled as hereinbefore described and as illustrated in FIGS. 10 to 13. [0041] The top grid 30 is assembled as a regular lattice of parallel, spaced 30 line wires 31 overlying parallel, spaced cross wires 32 at respective joints 33, the latter being best illustrated in FIG. 9; and the top grid 30 is located above the base frame 21 so that each joint 33 overlies a timber slat 25. 2118496v1 8 [0042] Referring to FIG. 6, a spring module 10 is advanced towards an adjacent pair of the joints 33 in the top grid 30, with the legs 54, 55 of the module 10 substantially- horizontal. The arch portions 70, 70A of the hook-like grid support members 60, 61 are engaged with respective line 5 wires 31 and abut the cross wire 32. [0043] As illustrated in FIG. 7, the spring module 10 is hingedly moved downwardly about a hinge axis defined by the cross wire 32, and the cross wire 32 enters the cradle potions 65, 66, 65A, 66A of the grid support members 60, 61. 10 [0044] As illustrated in FIG. 8, the movement of the spring module 10 continues until it is located in its substantially-upright position, with the foot 50 located on the top face of the timber slat 25. [0048] When the intermediate foot portion 51 is aligned with the centerline of the timber slat 25, the foot 50 is secured to the timber slat by staples 15 80, as illustrated in FIG. 4. [0045] A plurality of the spring modules 10 are connected to respective pairs of joints 33 in the top grid 30, and secured to the timber slat 25, until the foundation frame is assembled as illustrated in FIGS. 10 to 13. [0046] The skilled addressee will appreciate alternative fixing means e.g. 20 nails or clips with integral spikes, may be used to secure the feet 50 of the spring modules 10 to the slats 25. [0047] The skilled addressee will also appreciate that the height of the legs 54, 55 may be varied so that the vertical spacing between the base frame 21 and the top grid 30 in the foundation frame 20 can be varied. 25 [0048] In addition, the skilled addressee will appreciate the gauge / tensile strength of the wire stock(s) forming the spring modules 10, line wires 31 & cross wires 32 can be varied to suit the intended use of the bedding foundation e.g. a single child's bed or a commercial king-size bed (for hotels or the like). 30 [0049] Advantages of the invention include, but are not limited to: a) Securely locks top grid joints together without welding or additional fixings; 2118496v1 9 b) The unique 'hook/lever' action of the modules simplifies their assembly onto the top grid;. c) The assembly method requires less skill and reduces the risk of workplace injuries. 5 d) Offers less permanent deflection than the existing modules under impact testing. e) Uses (e.g. 30%) less wire than existing modules, giving a corresponding reduction in material costs. f) The angled legs form a series of triangulated braces across the foundation, 10 offering good lateral stability for the top grid, as minimised sideways movement is seen as a positive feature for bedding foundations. [0050] Possible variations to the invention include: a) The new design utilises Sealy Australia's existing top grid design, with formed dimples allowing the line wires and cross wires to interlock for a 15 secure joint; b) It is possible to create variations of this design concept with reduced (or no) forming of the top grid wires. While this results in less secure grid joints; however, it remains a possible design variation; and c) The foot of the module may be formed in various shapes as long as it 20 provides a flat form to be stapled, nailed or otherwise securely fixed to the top of the timber base frame. [0051] Various other changes and modifications may be made to the embodiments described and illustrated without departing from the present invention. 25 30 2118496v1

Claims (5)

1. A bedding foundation spring module, having an elongate body formed of spring steel or like material, including: 5 a foot securable to a base frame of a bedding foundation; a respective upstanding leg at each end of the foot; and a grid support member at an upper end of each leg; each grid support member being of substantially U-shape in plan, with a pair of spaced cradle portions, each cradle being defined by a pair of 10 spaced shoulders; each grid support member being arranged to receive and engage a cross wire and a line wire at a joint in a top grid of a bedding foundation frame.

2. The module of claim 1, wherein: 15 each grid support member has an arch portion, interconnecting the pair of cradle portions, and operable to pass over the upper of the line wire or the cross wire at the joint and restrain the wires at the joint.

3. The module of claim 2, wherein: 20 the respective grid support members are oppositely directed relative to their respective legs, and overlie the respective end portions of the foot; . each grid support member has a proximal end, connected to the respective leg, forming one of the pair of shoulders of one of the cradle portions; and a distal end, forming one of the pair of shoulders of the 25 other cradle portion, and terminating in a downwardly-directed tail; and the arch portion of each grid support member provides the other of the pair of shoulders for both cradle portions.

4. The module of any one of claims 1 to 3, wherein: 30 the foot is of substantially Z-shape in top plan view, with an intermediate portion securable to the base frame by fasteners; the legs extend upwardly from distal ends of end portions of the foot; and 2118496v1 11 at least one of the legs is inclined to the vertical z-axis, in the horizontal y axis when in use, so that the cradle portions are substantially aligned with the intermediate portion of the foot; and, optionally: the legs are oppositely inclined to the z-axis in the horizontal x-axis. 5

5. A method of assembling a frame for a bedding foundation, including the steps of: a) forming a base frame for a bedding foundation, the base frame having a plurality of slats; 10 b) forming a top grid of a regular lattice of spaced line wires intersected by spaced cross wires at respective joints in the top grid; c) engaging a respective arch portion of each grid support member of a module, as claimed in claim 2 or claim 3, over the respective line or cross wires at an adjacent pair of joints in the top grid, with the module 15 extending substantially horizontally; d) hingedly moving the module downwardly towards a substantially vertical position, to cause the cross or line wire interconnecting the line or cross wire, to be received in, and engaged by, each pair of spaced cradles of each grid support member at each joint; and 20 e) securing the foot of the module to a slat of the base frame; and f) repeating steps c) to e) until all joints in the top grid are supported above the base frame by a plurality of the modules. 25 30 2118496v1