AU2010203064A1 - Track for mobile shelving - Google Patents

Description

Pool Section 29 Regulation 3.2(2) AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT pplication Number: Lodged: Invention Title: Track for mobile shelving The following statement is a full description of this invention, including the best method of performing it known to us: 1 TRACK FOR MOBILE SHELVING FIELD OF THE INVENTION The present invention relates to low-profile tracks and track-and-runner assemblies for mobile shelving. 5 BACKGROUND TO THE INVENTION In office and other environments it is common to employ mobile shelving systems in order to maximise storage space. Individual shelving units can be moved along tracks by rollers in order to access items stored therein when needed. As a shelving unit moves along the track, unevenness in the track or in 10 the force applied to the shelving unit may lead to creation of an overturning moment and to toppling of the unit. Furthermore, unevenness in track levels must generally be corrected by the use of shims or packers positioned beneath the complete track structure, resulting in a visually unappealing product. One way of reducing the risk of toppling is described in Australian patent 15 no. 634902, in which the track includes a longitudinal slot extending laterally into the track from a side. At least one of the runners of the shelving unit has a stabiliser with a flange which enters the slot and moves within it during normal movement of the runner along its track, without engaging the slot surfaces. If there is a tendency for the cabinet to topple, the flange will move into 20 engagement with a slot surface and inhibit such toppling movement. Although the anti-tip mechanism described in AU634902 may prevent toppling once it is initiated, it still allows for the creation of dynamic overturning forces due to the clearance between the flange and the slot. Furthermore, once the flange engages with a surface of the slot it creates a pivot point which will 25 tend to accentuate any overturning moment. SUMMARY OF THE INVENTION The present invention seeks to overcome one or more of the abovementioned deficiencies including substantially avoiding the creation of an overturning moment. 30 In one aspect, the invention provides a track and runner assembly for a mobile shelving unit, including: a track having an elongate protrusion with a convex transverse cross section and extending longitudinally along the track, said track further including at 2 least one channel running parallel to the elongate protrusion and opening in a sideways direction, and a runner including at least one wheel rotatable about a generally horizontal axis and having a circumferential groove, the or each said groove 5 having a shape complementary to the convex shape of the elongate protrusion whereby the wheel or wheels will, in use, roll along said elongate protrusion; the runner further including at least one anti-tip wheel rotatable about a generally upright axis; whereby, in use during motion of the shelving unit along said track, the or 10 each said anti-tip wheel rolls within a said channel to prevent toppling of the unit. By providing the combination of a grooved wheel (and complementarily shaped track) with an anti-tip device in the form of a wheel rolling within a channel, it is possible to substantially eliminate the creation of an overturning moment since alignment and engagement of the grooved wheel and anti-tip 15 wheel with the track are maintained at all times while the shelving unit is in motion. The rotation of the anti-tip wheel greatly reduces the possibility of the shelving unit "locking" in place and forming a pivot point about which an overturning moment can be generated. In a preferred embodiment, the track includes an upper portion including 20 the elongate protrusion, and a base which is formed separately from the upper portion. This enables the placement of shims or "packers", used for adjusting the height of the track, between the base and upper portion. The packers may thus be obscured from view, providing for a significantly more visually attractive system. 25 The track may further include at least one recessed zone in the base and/or the upper portion, the or each said recessed zone being shaped to receive an elevated portion of a packer. This enables the packer to be held securely in place by virtue of the engagement of the elevated portion with the aperture. The upper portion of the track may be configured to be received in an 30 upwardly open location channel in said base, the or each said channel opening in a sideways directions being formed between a region of said upper portion and said base.

3 Mobile shelving units of the type used with the present invention generally run along a pair of parallel tracks. When installing the tracks, it is important to ensure that they are level with respect to one another. Provision of a two-piece track construction in the form of a separately formed base and upper portion 5 advantageously allows the upper portion to be used as a levelling tool. The upper portion of one of the parallel tracks may be laid transversely on top of the two base portions. If a spirit level placed on top of the upper portion indicates that one track is lower than the other, one or more packers may be placed within that track to level the tracks. 10 The track may be formed of a plurality of track sections. Each said track section preferably includes one or more cavities for insertion of a rod to align and join the track section with another said track section. The upper portion and base of the track may be made from the same material, or alternatively may be made from different materials. 15 The runner may include at least one anti-tip wheel on each side of the elongate protrusion to further improve the stability of the shelving unit as it moves along the track. Preferably, the elongate protrusion has substantially semi-circular transverse cross section. In this embodiment, the load distribution across the 20 track is optimised. The track is preferably made from aluminium or aluminium alloy, and preferably includes a ramp on each side of the elongate protrusion. The ramps preferably have a gradient of 1:8 to enable a person in a wheelchair to cross the tracks if desired. 25 In another aspect, the present invention provides a track section for a mobile shelving unit, including: an upper portion, and a base which is formed separately from the upper portion. The track section may further include at least one recessed zone in the base and/or the upper portion, the or each said recessed zone being shaped to 30 receive an elevated portion of a packer. The upper portion may include at least one cavity to accommodate a rod for aligning and connecting the track section with another track section.

4 In a further aspect, there is provided a packer for a track for mobile shelving, the track having a base and an upper portion which is formed separately from the base, the base and/or the upper portion having at least one recessed zone therein, the packer including an elevated portion which is shaped to locate 5 within a said recessed zone in said upper portion and/or base. Preferably, the packer is formed by a first plate section defining a first plane and the or each elevated portion is formed from the first plate section extending transversely to the first plane. The first plate section may include at least one opening to accommodate at least one of the elevated portions of a 10 second packer extending at least partially through the opening. The elevated portion may be formed as a ridge portion, or alternatively may be a tab section bent from the first plate section. If the elevated portion is a ridged portion, the ridged portion may be hollow to accommodate a second ridged portion of a second packer to enable the 15 packers to be stacked. In a yet further aspect, the present invention provides a track section for a mobile shelving unit including a base, an upper portion separate from said base, said base and said upper portion being configured to engage in use with one another whereby the upper portion is restrained against transverse movement 20 relative to said base, a first recessed zone being formed in at least one surface of the upper portion or the base facing one another when the upper portion is engaged in use with said base, and at least one packer positionable between a region of surfaces facing one another of said base and said upper portion, said packer being formed by a first plate section defining a first plane and at least one 25 elevated portion formed from said first plate section extending transversely to said plane, said elevated portion being, in use, receivable in said first recessed zone. The present invention also provides, in yet another aspect, a mobile shelving unit for use with a track having an elongate protrusion with a convex transverse cross section and extending longitudinally along the track, said track 30 further including at least one channel running parallel to the elongate protrusion and opening in a sideways direction, the mobile shelving unit including: a runner, including: 5 at least one wheel rotatable about a generally horizontal axis and having a circumferential groove, the or each said groove having a shape complementary to the convex shape of the elongate protrusion whereby the wheel or wheels will, in use, roll along said elongate protrusion; and 5 at least one anti-tip wheel rotatable about a generally upright axis; whereby, in use during motion of the shelving unit along said track, the or each said anti-tip wheel rolls within a said channel to prevent toppling of the unit. BRIEF DESCRIPTION OF THE DRAWINGS Preferred embodiments of the invention are now described, by way of non 10 limiting example, with reference to the accompanying drawings in which: Figure 1 is a transverse cross-sectional view through a track and runner assembly according to the present invention; Figure 2(a) is a transverse cross-sectional view through the track of Figure 1, shown in its unassembled form; 15 Figure 2(b) shows an alternative track upper portion for use with the track of Figure 2(b); Figure 3(a) shows a top view of a packer for use with the two-piece track of Figures 1 and 2; Figure 3(b) is a first side view of the packer of Figure 3(a); 20 Figure 3(c) is a cross-section through the line 3-3 of Figure 3(a); Figure 3(d) is a second side view of the packer of Figure 3(a); and Figure 4 shows alternative embodiments of a packer for use with the track of Figures 1 and 2; and Figures 5(a) and 5(b) show cross-sectional and perspective views of an 25 alternative track for use with the present invention. DESCRIPTION OF PREFERRED EMBODIMENTS Referring to Figures 1 and 2, there is shown a runner 30 attached to one side of a mobile shelving unit 10. A mobile shelving system will generally include multiple such shelving units 10. 30 A second runner (not shown) is attached to the other side of the shelving unit 10 so that the shelving unit may move along a pair (or three, four, etc) of parallel tracks 20. In general each track 20 will consist of a plurality of track 6 sections which are joined together, and in the following description of the preferred embodiments, "track" and "track section" will be used interchangeably. The track section 20 has a base 24 and upper portion 22, each of which may be lengths of extruded aluminium, for example. Upper portion 22 includes an 5 elongate protrusion 25 of substantially semi-circular cross section. The protrusion 25 extends along the length of the track section 20 and is of substantially uniform cross section along the track. The runner 30 includes a grooved wheel 32, the circumference 34 of which is shaped to accommodate the protrusion 25. As the wheel 32 rolls along the 10 protrusion 25 it rotates about a generally horizontal axis 33. The runner also includes at least one anti-tip wheel 36 to one side of the grooved wheel 32 and elongate protrusion 25 which rotates about a generally upright axis 37 during motion of the shelving unit 10. In alternative embodiments, one or more additional anti-tip wheels may be provided on the opposite side of the elongate protrusion 15 25 to anti-tip wheel or wheels 36. The anti-tip wheel 36 has a circumferential section 38 which is angled so as to match the slope of a ramp 27. The circumferential section 38 is also shaped so as to be complementary to a channel 26 which runs parallel to the elongate protrusion 25 and opens outwardly in a sideways direction from the track 20. This 20 permits anti-tip wheel 36 to roll along channel 26 as the shelving unit moves along the track 20. At the same time, the grooved wheel 32 rolls along the protrusion 25. Each wheel thus remains engaged with the track, and the angled configuration of the anti-tip wheel minimises the clearance between the anti-tip wheel and the ramp. These attributes of the runner ensure that misalignment of 25 the runner relative to the track, which would create an overturning moment, is prevented. The ramps 27 of the track 20 are not essential, but are highly advantageous for wheeled vehicles such as trolleys and wheelchairs to be moved between pairs of adjacent shelving units. 30 If ramps are not required, then the upper surfaces 27 of base 24 may instead be substantially horizontal in which case the circumferential section 38 of wheel 36' would also be substantially horizontal.

7 Referring now to Figure 2(a) there is shown a two-piece track section 20. An upper portion 22 of track section 20 includes flanges 23 so that when upper portion 22 and base 24 are assembled as in Figure 1 (by placing upper portion 22 in upwardly open location 28 in base 24), the flanges 23 and ramps 27 form the 5 channels 26 therebetween to accommodate the anti-tip wheel 36. During installation of a mobile shelving system including a pair of parallel tracks 20, the upper portion 22 may advantageously be used as a levelling bar for the tracks. Upper portion 22 can be laid cross-wise on top of a pair of bases 24, and a spirit level laid on top of upper portion 22 to determine whether the bases 24 are level. 10 If one base is lower than the other, one or more shims or "packers" may be inserted between that base and its corresponding upper portion to level the two tracks. The upper portion 22 also includes two cavities 21 for accommodating rods (not shown). The rods allow track section 20 to be aligned with another track 15 section. Once inserted, the rods are pinned in place to effect a join between the two track sections. The cavities may extend partly into the upper portion 22 to form a blind bore, or may extend all the way along its length. Figure 2(b) shows an alternative upper portion 22 suitable for placement within the upwardly open location 28 of track 24. In this embodiment, cavities 21 20 serve a dual purpose as they not only permit the placement of rods therein for aligning and forming adjacent trade sections, but also accommodate the ridged portion or portions of a packer of the type shown in Figures 3 and 4. In Figure 3, there is shown a packer 40 according to one embodiment of the present invention. The hollow ridged portion 41 of packer 40, which in this 25 embodiment is an elongate triangular prism, is shaped to fit into correspondingly shaped recessed zones 29 in the upper portion 22 of track 20. It may also be used with the upper, portion 22 of Figure 2(b), the ridged portion 41 being accommodated by cavity 21' in that case.. The hollow ridge 41 may also accommodate the ridged portion of a second packer (not shown) so that packers 30 may be stacked to achieve the desired height. Alternatively, the ridged portion of the second packer could be accommodated by cut-out portion 42 for stacking purposes.

8 Figure 4 illustrates two alternative embodiments 50a, 50b of the packer of the present invention. Each packer 50a, 50b has (upright elevated) portions 51a, 51 b bent from a cut out zone 52a, 55b of the plate forming the packer 50a, 50b. The elevated portions 51a, 51b may, in use, be accommodated in cut-out portions 5 52b-55b or 52a-55a respectively. For example, packer 50a could be stacked on top of packer 50b by inserting elevated portions 51b into cut-out portions 55a or 53a so that the edges 57a, 57b of the two packers are substantially aligned; or elevated portions 51b could be inserted into cut-out portions 54a or 52a to introduce an offset between edges 57a and 57b. it will be realised that packers 10 50a, 50b could be used with either of the upper portions 22, 22', with elevated portions 51a, 51b being accommodated by recesses 29 or 21' accordingly. In Figure 5 there is shown an alternative embodiment of a track 120 which could replace the track 20 of Figure 1. Track 120 is formed as a single piece of extruded aluminium, or aluminium alloy allowing for a simpler manufacturing 15 process than track 20. Although the track 120 shown in Figure 5(b) is shown as being relatively short and wide, in practice each section of track will be generally elongate in nature, and of course may be varied in length and/or width according to the particular type of shelving unit employed in the shelving system. The skilled addressee will appreciate that many modifications and variations of 20 these exemplary embodiments are possible, whilst remaining within the scope of the invention as claimed herein. The example, a shelving unit may be configured to move along three, four or even more substantially parallel tracks should it be so desired. In this case, each track would be accompanied by a runner substantially as described in the foregoing. 25

Claims (19)

1. A track and runner assembly for a mobile shelving unit, including: a track having an elongate protrusion with a convex transverse cross section and extending longitudinally along the track, said track further including at 5 least one channel running parallel to the elongate protrusion and opening in a sideways direction, and a runner including at least one wheel rotatable about a generally horizontal axis and having a circumferential groove, the or each said groove having a shape complementary to the convex shape of the elongate protrusion 10 whereby the wheel or wheels will, in use, roll along said elongate protrusion; the runner further including at least one anti-tip wheel rotatable about a generally upright axis; whereby, in use during motion of the shelving unit along said track, the or each said anti-tip wheel rolls within a said channel to prevent toppling of the unit. 15

2. A track and runner assembly according to claim 1, wherein the track includes an upper portion including the elongate protrusion, and a base which is formed separately from the upper portion.

3. A track and runner assembly according to claim 2, further including at least one recessed zone in the base and/or the upper portion, the or each said 20 recessed zone being shaped to receive an elevated portion of a packer.

4. A track and runner assembly according to claim 2 or claim 3, wherein the upper portion is configured to be received in an upwardly open location channel in said base, the or each said channel opening in a sideways direction being formed between a region of said upper portion and said base. 25

5. A track and runner assembly according to any one of the preceding claims, wherein the runner includes at least one anti-tip wheel on each side of the elongate protrusion. 10

6. A track and runner assembly according to any one of the preceding claims, wherein the track includes a plurality of track sections.

7. A track and runner assembly according to claim 6, wherein each said track section includes at least one cavity to accommodate a rod for aligning and 5 connecting the track section with another said track section.

8. A track and runner assembly according to any one of the preceding claims, wherein the elongate protrusion has substantially semi-circular transverse cross section.

9. A track section for a mobile shelving unit, including: an upper portion, and 10 a base which is formed separately from the upper portion.

10. A track section according to claim 9, further including at least one recessed zone in the base and/or the upper portion, the or each said recessed zone being shaped to receive a ridged portion of a packer.

11. A track section according to claim 9 or claim 10, wherein the upper portion 15 includes at least one cavity to accommodate a rod for aligning and connecting the track section with another said track section.

12. A packer for a track for mobile shelving, the track having a base and an upper portion which is formed separately from the base, the base and/or the upper portion having at least one recessed zone therein, the packer including at 20 least one elevated portion which is shaped to locate within a said recessed zone in said upper portion and/or the base.

13. A packer according to claim 12 wherein said packer is formed by a first plate section defining a first plane and the or each said elevated portion being formed from said first plate section extending transversely to said first plane. 25

14. A packer according to claim 13 wherein said first plate section includes at least one opening to accommodate at least one opening to accommodate at least 11 one said elevated portion of a second said packer extending at least partially therethrough.

15. A packer according to claim 13 or claim 14 wherein the elevated portion is formed as a ridge portion. 5

16. A packer according to claim 13 or claim 14 wherein the elevated portion is a tab section bent from said first plate section.

17. A packer according to claim 15, wherein the ridged portion is hollow to accommodate a second ridged portion of a second said packer.

18. A track section for a mobile shelving unit including a base, an upper 10 portion separate from said base, said base and said upper portion being configured to engage in use with one another whereby the upper portion is restrained against transverse movement relative to said base, a first recessed zone being formed in at least one surface of the upper portion or the base facing one another when the upper portion is engaged in use with said base, and at 15 least one packer positionable between a region of surfaces facing one another of said base and said upper portion, said packer being formed by a first plate section defining a first plane and at least one elevated portion formed from said first plate section extending transversely to said plane, said elevated portion being, in use, receivable in said first recessed zone. 20

19. A mobile shelving unit for use with a track having an elongate protrusion with a convex transverse cross section and extending longitudinally along the track, said track further including at least one channel running parallel to the elongate protrusion and opening in a sideways direction, the mobile shelving unit including: 25 a runner, including: at least one wheel rotatable about a generally horizontal axis and having a circumferential groove, the or each said groove having a shape complementary to the convex shape of the elongate protrusion whereby the wheel or wheels will, in use, roll along said elongate protrusion; and 12 at least one anti-tip wheel rotatable about a generally upright axis; whereby, in use during motion of the shelving unit along said track, the or each said anti-tip wheel rolls within a said channel to prevent toppling of the unit. COMMANDO STORAGE SYSTEMS PTY LTD WATERMARK PATENT & TRADE MARK ATTORNEYS P32021 AUQO