Swivel base with installation aid   

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to swivel bases having a detent that can be used to pivotally support platforms, lazy susans and cabinets with at least one preferred stopping position. The present invention also relates to features facilitating the installation of such swivel bases.

2. Description of the Prior Art

There are presently available a number of support systems for pivotally supporting platforms, shelves and movable cabinets within an enclosure. For example, kitchen corner cabinets are often provided with one or more shelves that are supported for rotation as a unit so that the goods on the shelves can be more easily accessed. Typically the support mechanism includes at least one detent that can be used to define a “closed” position for the shelving unit. The detent-defined closed position can facilitate the positioning of doors or face mountings to ensure an enhanced appearance to the cabinet as a whole. The correct positioning of the detent defining mechanism in the cabinet is required to avoid any skewed appearance to the unit when in the “closed” position.

A representative prior art support system for pivotally supporting a shelf within a cabinet is disclosed in U.S. Pat. No. 4,440,459. The support system includes a hub receptacle affixed to the bottom of a shelf unit. An adjustable hub is mounted on a plate attached to the floor of the cabinet. The hub is received within the hub receptacle projecting downwardly from the bottom shelf when the shelf is positioned within the cabinet. Detents are provided in the hub receptacle and followers project outward from the hub to engage the detents to assist in maintaining the rotary shelf unit in a desired detent defined position. Adjustment of the detent defined position is achieved by adjusting the angular position of the hub on the plate. Wheels attached to the bottom shelf ride on the plate and support the shelf unit. Through repeated engagement and disengagement of the detents and followers, the hub can become loosened so that the detent defined position is no longer accurate.

A preferred support system would be a single pre-assembled unit that could be easily and quickly installed by a cabinet manufacturer. The preferred support system would be rugged enough to support any load that would reasonably be anticipated in a given installation. The preferred support system, once installed, would not be subject to loosening that could affect the desired detent defined position.

SUMMARY

A support system of the present invention includes a swivel that can have a first member including a plurality of openings to receive fasteners for securing the first member to an underlying base. The swivel can also include a second member that can be mounted to a lower surface of a shelf unit. The second member is pivotally connected to the first member and defines an axis of rotation for the shelf unit relative to the base. At least one projection projects from a lower surface of the first member for engagement with the underlying base to facilitate a secure alignment of the first member relative to the underlying base. An aperture can be provided in the shelf unit to facilitate the attachment of the first member to the underlying base. A plug can be inserted into the aperture following attachment of the first member to the underlying base.

The swivel first member can include a race surface facing radially outward, while the swivel second member can include a race surface confronting the race surface of swivel first member. A plurality of low friction members can be positioned between the race surfaces of the swivel first and second members. The low friction members can take the form of balls, which can be made of metal such as steel or of a polymer such as nylon or polyoxymethylene (Delrin). The swivel first member can include a flange extending radially inward from a lower edge of the swivel first member race. The flange of the swivel first member can include the plurality of openings to receive fasteners for securing the first member to an underlying base. The swivel second member can include a support ridge obverse the second member race surface. The support ridge can include a plurality of channels and webs. Openings can be provided in the ridge to receive fasteners coupling the second member to a bottom surface of a shelf.

The second member can have a contoured surface including at least one pair of adjacent lobes separated by an indentation defining a detent. One or more support plates can be coupled to the first member, each support plate supporting a follower and biasing means biasing the follower into contact with the second member contoured surface. The contoured surface can be a radially outwardly facing surface of the second member. The follower can take the form of an arm pivotally connected to the support plate so as to move perpendicular to the contoured surface. The follower can have a wedge surface suitable for insertion in the indentation between the pair of adjacent lobes. The biasing means can take the form of a compression spring situated between the wedge surface of the follower and an upstanding flange on the support plate.

The support system swivel can be installed by securing the second member to a bottom surface of a shelf unit while a detent is engaged. The second member can be situated so that an axis of rotation defined by the second member race surface is aligned with a target axis of rotation of the shelf unit. The second member can also be situated so that one of the plurality of openings in the first member situated on an opposite side of the axis of rotation to the projection from the lower surface of the first member is aligned with an aperture in the shelf unit. The shelf unit can then situated in a cabinet at a desired location and orientation and a first fastener can be inserted through the aperture in the shelf unit to fasten the first member to the underlying base with sufficient force to ensure the projection located on the opposite side of the axis of rotation penetrates into the underlying base surface. The shelf unit can then be rotated on the swivel to disengage the follower from the detent to reveal through the shelf unit aperture additional openings in the first member, which can receive additional fasteners to secure the first member to the underlying base surface.

Other features and advantages of the present invention will become apparent to those skilled in the art from the following disclosure of preferred embodiments of the present invention exemplifying the best mode of practicing the invention. The following disclosure references the accompanying drawings illustrating the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a corner cabinet employing a swivel base to support a rotatable shelf.

FIG. 2 is a perspective view of an upper surface of a shelf such as can be employed in the cabinet shown in FIG. 1.

FIG. 3 is a perspective view of a lower surface of the shelf shown in FIG. 2 including a swivel base.

FIG. 4 is a perspective view of the upper surface of the swivel base shown in FIG. 3.

FIG. 5 is a bottom plan view of the swivel base shown in FIGS. 3 and 4 absent the stop mechanism.

FIG. 6 is a sectional view taken through line 6-6 of FIG. 5.

FIG. 7 is a sectional view taken through line 7-7 of FIG. 5.

FIG. 8 is a sectional view taken through line 8-8 of FIG. 5.

FIG. 9 is a perspective view similar to FIG. 4 of another swivel base having two stop mechanisms.

A corner cabinet 10 is shown in FIG. 1 to contain a shelf 12 that can be supported on a swivel base 14 to permit rotation of the shelf 12 within the cabinet 10. The cabinet 10 can include sides 16 and 18 having edges 20 and 22 defining an opening 24 in the cabinet. The swivel base 14 can include features described below intended to insure that the shelf 12 can be reliably oriented with respect to the opening 24. The swivel base 14 is situated between the shelf 12 and a cabinet base surface 26. The cabinet 10 can include a kick plate 28 situated below the base surface 26. A top 30 can join the sides 16 and 18 to each other. The top 30 typically includes a front edge 32, which can assume shapes other than that shown, further defining the opening 24. The cabinet 10 can also include back surfaces 34 and 36. A door panel, not shown, can be secured to the cabinet 10 or to the shelf 12 to close the opening 24 when the shelf 12 is rotated to a “rest” position.

The shelf 12 can have a top surface 38 as shown in FIG. 2. The shelf 12 can have a perimeter 40 defined by a rounded back portion 42 and a front edge 44. The front edge 44 can be linear as shown in FIG. 2 or can include a generally V-shaped indentation depicted by phantom line 46, and can assume some other shapes, not shown. The shelf 12 can be rotated about a point 48 equal distant from all points on the rounded back portion 42. The shelf 12 can include an aperture 50 that extends through the shelf 12 from the top surface 38 to the bottom surface 52. A plug 54 can be provided to close the aperture 50 following installation of the shelf 12.

The bottom surface 52 of the shelf 12 is shown in FIG. 3. The swivel base 14 is shown attached to the bottom surface 52. The swivel base 14 can include a smaller inner ring 56 and a larger outer ring 58, which is larger than the smaller ring 56. The larger ring 58 can be secured to the bottom surface 52 of the shelf 12 by a plurality of fasteners 60 so that the ring is centered around point 48. A support plate 62 can be secured to the smaller ring 56.

An upper surface 64 of the larger outer ring 58 can be seen in FIG. 4. A plurality of openings 66 are seen in the upper surface 64 that can receive the fasteners 60 to secure the ring 58 to the bottom surface 52 of the shelf 12. An outer surface 68 of the outer ring 58 can be seen to include a contoured surface portion 70 including a pair of radially outwardly projecting lobes 72 separated by an indentation 74 defining a detent 76. The smaller ring 56 is seen to include an inwardly extending flange 78. A plurality of openings 80 can be spaced around the flange 78 to receive fasteners, not shown, for securing the smaller ring 56 to the underlying surface 26. A pair of projections 82 can be fixed to the flange 78 so as to straddle opening 84, which is one of the openings 80. An opening 85, which is one of the openings 80, is located adjacent to the indentation 74 defining the detent 76.

The support plate 62 can be seen to be secured to the smaller ring 56 by a plurality of fasteners 86. The support plate 62 supports an arm 88 on a pivot mechanism 90. The arm 88 can have a wedge surface 92 suitable for insertion into the indentation 74 between the pair of adjacent lobes 72 on the contoured surface 70 of the larger outer ring 58. A spring 94 can be situated between an obverse surface 96 of the arm and an upstanding flange 98 of the support plate 62. The spring 94 can bias the wedge surface 92 as a follower into contact with the surface 68 of the outer ring 58. The rings 56 and 58 are shown in FIG. 4 in a “rest” position with the wedge surface 92 received in the indentation 74.

A lower surface 100 of the larger outer ring 58 can be seen in FIG. 5. The lower surface 100 can include a plurality of arcuate channels 102 as shown in cross section in FIG. 7. The arcuate channels 102 can be separated by a plurality of partial height webs 104 as shown in cross section in FIG. 6 and full height webs 106 as shown in cross section in FIG. 8. FIG. 5 also shows the openings 80 spaced around the flange 78 of the inner ring 56. Additional openings 108 are shown in the flange 78 intended to receive the fasteners 86 for securing the support plate 62 to the ring 56.

FIG. 6 shows a sectional view taken through line 6-6 of FIG. 5 revealing an outwardly facing race surface 110 on the inner ring 56. An inwardly facing race surface 112 can be seen on the outer ring 58 to confront the race surface 110. The race surfaces 110 and 112 can extend completely around the inner ring 56 and outer ring 58, respectively. A plurality of low friction members 114 can be positioned between the race surfaces 110 and 112 to facilitate the relative rotation of the swivel base members 56 and 58. The low friction members 114 can take the form of balls, which can be made of metal such as steel. Other materials that can be used for the low friction members 114 include polymers such as nylon or polyoxymethylene (Delrin).

FIG. 7 shows a sectional view taken through line 7-7 of FIG. 5 again revealing the outwardly facing race surface 110 on the inner ring 56 confronting the inwardly facing race surface 112 on the outer ring 58, the race surfaces 110 and 112 being separated by the low friction members 114. FIG. 7 also reveals the depth of the arcuate channels 102 and the projections 82 extending downward below the lower surface 116 of the flange 78 of the smaller inner ring 56. The projections 82 can be seen to have a point 118 suitable for piercing the base surface 26. The projections 82 can take the form of hardened steel points pressed or screwed into the flange 78 at the indicated locations so as to extend below the lower surface 116 by about 0.030 inches (0.76 mm).

FIG. 8 shows a sectional view taken through line 8-8 of FIG. 5 again revealing the outwardly facing race surface 110 on the inner ring 56 confronting the inwardly facing race surface 112 on the outer ring 58, the race surfaces 110 and 112 being separated by the low friction members 114. FIG. 8 also reveals one of the fasteners 60 received in one of the openings 66 extending through the thickest portion 106 of the outer ring 58. The fasteners 60 are used to secure the outer ring 58 to the bottom surface 52 of the shelf 12 as shown in FIG. 3. FIG. 8 also reveals a fastener 118 extending through one of the openings 80 in flange 78 of the inner ring 56. The fasteners 118 act to secure the inner ring 56 to the base surface 26 of the cabinet 10 or other similar structure.

The shelf 12 can be installed into the base surface 26 of the cabinet 10, or other similar structure, by first securing the outer ring 58 of the swivel base 14 to the lower surface 52 of the shelf 12 so that the aperture 50 through the shelf 12 can be aligned serially with the plurality of openings 80 in flange 78 of the inner ring 56. Next, the shelf 12, with the swivel base 14 attached, is positioned on the underlying base surface 26 at a desired location in relation to the cabinet opening 24 with the aperture 50 through the shelf 12 aligned with one of the openings 80 in flange 78, preferably opening 85 situated adjacent to the indentation 74 defining the detent 76. A first fastener 118 is inserted through the shelf aperture 50 into the aligned first swivel member opening 80 into engagement with the underlying base 26 with sufficient force to embed the projections 82 on the opposite side of the ring 56 in the underlying base surface 26. The penetration of the single first fastener 118, preferably into opening 85, and the projections 82 sufficiently stabilizes the position of the swivel base 14 so that the shelf 12 can be rotated to reveal serially each of the other openings 80 through the aperture 50. As each opening 80 is revealed, another fastener 118 can be installed to secure the position of the flange 78, and swivel base 14, on the underlying base 26 of the cabinet 10. Following installation of fasteners 118 in all of the openings 80, the plug 54 can be installed into the upper surface 38 of shelf 12 to hide any appearance of the aperture 50.

This same or similar installation method can be used to install swivel bases 14 not having a follower mechanism defining a “rest” position. The same or similar installation method can also be used to install swivel bases 14 having more than one follower mechanism as shown in FIG. 9. FIG. 9 is a perspective view similar to FIG. 4 of another swivel base 120 having two support plates 62 secured to the smaller ring 56 by a plurality of fasteners 86 on opposite sides of the axis of rotation Y of the swivel base 120. Each of the support plates 62 supports an arm 88 on a pivot mechanism 90. Each arm 88 can have a wedge surface 92 suitable for insertion into the indentation 74 between the pair of adjacent lobes 72 on the contoured surface 70 of the larger outer ring 58. Each spring 94 can be situated between an obverse surface 96 of the arm and an upstanding flange 98 of the respective support plate 62. Each spring 94 can bias the adjoining wedge surface 92 as a follower into contact with the surface 68 of the outer ring 58. The rings 56 and 58 are shown in FIG. 9 mid-way between two “rest” positions defined by one of the wedge surfaces 92 being received in the indentation 74.

From the forgoing description of the structure and operation of a preferred embodiment of the present invention, it will be apparent to those skilled in the art that the present invention is susceptible to numerous modifications and embodiments within the ability of those skilled in the art and without exercise of the inventive facility. Accordingly, the scope of the present invention is defined as set forth of the following claims.