Convertible multilevel shelving unit and display fixture

Abstract

A display fixture having a plurality of display panel assemblies that can each be independently pivoted between and held in either a horizontal and a vertical position may be easily configured for use as either a shelving unit or a display rack or a combination shelving unit and display rack by a user.

Claims

1. A display fixture comprising: a. a base; b. first and second vertical support rails mounted to and projecting upwardly from the base in parallel, spaced apart relation; and c. a plurality of display panel assemblies, each of the display panel assemblies comprising at least one display panel held by a frame pivotally coupled to each of the first and second vertical support rails, wherein each display panel assembly is adapted to independently and selectively pivot between a horizontal position in which the display panel assembly is adapted to serve as a shelf and a vertical position in which the display panel assembly is adapted to support at least one accessory, and wherein each of the display panel assemblies is associated with at least one latch assembly adapted to be engaged to prevent the display panel assembly from pivoting and adapted to be disengaged to enable the display panel assembly to pivot between the horizontal position and the vertical position, said latch assembly comprising a stationary stop and a retractable stop.

2. The display fixture of claim 1 wherein the base is mounted on a plurality of wheel assemblies.

3. The display fixture of claim 1 wherein the base includes a storage compartment.

4. The display fixture of claim 1 wherein the base has a front end and a back end.

5. The display fixture of claim 4 wherein the first and second vertical support rails extend from an area of the base half way between the front end and the back end.

6. The display fixture of claim 4 wherein first and second vertical support rails extend from an area of the base immediately adjacent the back end.

7. The display fixture of claim 1 wherein each of the display panel assemblies comprises a second display panel.

8. The display fixture of claim 1 wherein said at least one display panel is a sheet of pegboard having a plurality of holes arranged in a pattern and said at least one accessory is a hook adapted to by coupled to at least one of the holes of the pegboard.

9. The display fixture of claim 1 wherein said retractable stop is adapted to slide between a locked position in which a selected panel assembly is prevented from pivoting and an unlocked position in which the selected panel assembly can pivot between a horizontal position and a vertical position.

10. The display fixture of claim 1 wherein the frame of at least one of the plurality of display panel assemblies is adapted to hold two pegboard panels and two grid panels.

11. A display fixture comprising: a. a base having a front end and a back end and at least one storage compartment; b. first and second vertical support rails mounted to the base at the midpoint between the front end and back end of the base, said first and second vertical support rails projecting upwardly from the base in parallel, spaced apart relation; c. a plurality of display panel assemblies, each of the display panel assemblies comprising at least one display panel held by a frame, wherein said frame has a first end and a second end and is pivotally coupled along an axis of rotation between the first end and the second end to each of the first and second vertical support rails, wherein each of the display panel assemblies is adapted to independently and selectively pivot between a horizontal position in which the display panel assembly is adapted to serve as a shelf and a vertical position in which the display panel assembly is adapted to support at least one accessory, and wherein each of said display panel assemblies is associated with at least one latch assembly adapted to be engaged to prevent the display panel assembly from pivoting and adapted to be disengaged to enable the display panel assembly to pivot between the horizontal position and the vertical position, said latch assembly comprising a stationary stop and a retractable stop.

12. The display fixture of claim 11 further comprising a plurality of wheel assemblies supporting the base.

13. The display fixture of claim 11 wherein said retractable stop is adapted to slide between a locked position in which a selected display panel assembly is thereby prevented from pivoting and an unlocked position in which the selected display panel assembly can pivot between the horizontal position and the vertical position.

14. The display fixture of claim 11 wherein each of said display panels is selected from a group consisting of pegboard panels each having holes arranged in a pattern, and grid panels, and wherein said at least one accessory is adapted to be coupled to the selected panel when the panel assembly of which the selected panel is a part is in a vertical position.

15. A display fixture comprising: a. a base having a front end and a back end, b. a plurality of vertical support rails mounted to the base adjacent the back end of the base, each of said plurality of vertical support rails projecting upwardly from the base in parallel, spaced apart relation; and c. a plurality of display panel assemblies, each of the display panel assemblies comprising at least one display panel held by a frame having a first end and a second end, wherein the frame of each of the plurality of display panel assemblies is pivotally coupled along an axis of rotation adjacent the second end to a pair of said plurality of vertical support rails, wherein each of the display panel assemblies is adapted to independently and selectively pivot between a horizontal position in which the display panel assembly serves as a shelf and a vertical position in which the display panel assembly is adapted to support at least one accessory, and wherein each of said display panel assemblies is associated with at least one latch assembly adapted to be engaged to prevent the display panel assembly from pivoting and adapted to be disengaged to enable the display panel assembly to pivot between the vertical position, said latch assembly comprising a stationary stop and a retractable stop.

16. The display fixture of claim 15 wherein the base includes a storage compartment.

17. The display fixture of claim 15 wherein said retractable stop is adapted to slide between a locked position in which the selected display panel assembly is thereby prevented from pivoting and an unlocked position in which the selected panel assembly enabling the selected display panel assembly can pivot between the horizontal position and the vertical position.

18. The display fixture of claim 15 wherein when a selected display panel assembly of the plurality of display panel assemblies is in the vertical position, the second end of the selected display panel assembly faces downwardly.

19. The display fixture of claim 15 wherein each of said display panels is selected from a group consisting of pegboard panels each having holes arranged in a pattern, and grid panels, and wherein said at least one accessory is adapted to be coupled to the selected panel when the display panel assembly of which the selected panel is a part is in the vertical position.

20. The display fixture of claim 15 wherein said display panel assemblies are arranged in a plurality of rows and a plurality of columns.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The foregoing features, objects and advantages of the invention will become apparent to those skilled in the art from the following detailed description and with reference to the following drawings in which like numerals in the several views refer to corresponding parts.

(2) FIG. 1 is a perspective view of a display fixture made in accordance with the present invention with three display panel assemblies each in their respective horizontal positions;

(3) FIG. 2 is a perspective view of the display fixture of FIG. 1 with the top display panel assembly tilted slightly from its horizontal position and the other display panel assemblies in their respective horizontal positions;

(4) FIG. 3 is a perspective view of the display fixture of FIG. 1 with all the display panel assemblies in their respective vertical positions;

(5) FIG. 4 is a perspective view of the display fixture of FIG. 1, but with covers for the compartments in the base removed;

(6) FIG. 5 is an exploded view of the display fixture of FIG. 1;

(7) FIG. 6 is an exploded view of the pivot assembly and latch assembly of the display fixture of FIG. 1;

(8) FIG. 7 is an exploded view illustrating an alternative pivot assembly;

(9) FIG. 8 is an exploded view of the latch assembly used in the display fixture of FIG. 1 and a grid panel being employed as the display panel;

(10) FIG. 9 is a partial perspective view further showing the various components of a latch assembly used in the display fixture of FIG. 1 and a grid panel being employed as the display panel; and

(11) FIG. 10 is a partial perspective view showing a first embodiment of a latch assembly that may be employed when constructing the display fixture of FIG. 1 and how that latch assembly can secure one of the display panel assemblies in a vertical position;

(12) FIG. 11 is a partial perspective view of the latch assembly of FIG. 10 showing how the latch assembly can secure the panel assembly in the horizontal position;

(13) FIG. 12 is a perspective view of an alternative display fixture with each of eighteen independently positionable panel assemblies in their respective horizontal positions;

(14) FIG. 13 is a perspective view of the display fixture of FIG. 12 with each of the independently operable display assemblies in their respective vertical positions;

(15) FIG. 14 is a partial perspective view showing one of the display panel assemblies of the display fixture of FIG. 12 held in the horizontal position by an alternative latch assembly;

(16) FIG. 15 is a partial side view showing one of the bottom display panel assemblies of the display fixture of FIG. 12 held in the horizontal position by the latch assembly of FIG. 14;

(17) FIG. 16 is a partial side view showing an alternative embodiment of a latch assembly that may be employed when a display panel assembly is pivotally mounted to vertical support rails at the rear end of the display panel assembly as shown in FIGS. 12 and 13;

(18) FIGS. 17-20 illustrate alternative ways that pegboard panels and grid panels can be held in the frames of the display panel assemblies of the display fixtures;

(19) FIG. 21 is a perspective view showing a stop assembly attached to the bottom of the base of the display fixture of FIG. 1;

(20) FIG. 22 is a front view of a pegboard display panel of the type that may be employed in constructing the display panel assemblies;

(21) FIG. 23 is a perspective view of a hook of the type that may be employed when the display panel assemblies include a pegboard display panel;

(22) FIG. 24 is a perspective view of a basket of the type that may be employed when the display panel assemblies include a pegboard display panel; and

(23) FIG. 25 is a partial perspective view of a grid display panel of the type that may be employed in constructing the display panel assemblies together with a basket removably coupled to the grid display panel.

DETAILED DESCRIPTION

(24) The description of the preferred embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description of this invention. In the description, relative terms such as lower, upper, horizontal, vertical, above, below, up, down, top and bottom as well as derivatives thereof (e.g., horizontally, downwardly, upwardly, etc.) should be construed to refer to the orientation as then described or as shown in the drawings under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms such as connected, connecting, attached, attaching, join and joining are used interchangeably and refer to one structure or surface being secured to another structure or surface or integrally fabricated in one piece, unless expressly described otherwise.

(25) A display fixture 10 supported by a support surface 1 (such as the ground or a floor) is illustrated in the various drawings. The display fixture 10 includes a base 12. As shown in FIG. 1, the base 12 may be supported above a support surface 1 by a plurality of wheel assemblies 14 coupled to the bottom of base 12. The wheel assemblies 14 may be caster wheel assemblies as shown to assist in steering the display fixture 10 as the display fixture 10 is moved across the support surface 1. The wheel assemblies 14 may also be provided with locks as shown to selectively prevent rotation of the wheels. Such caster wheel assemblies having locks are well-known. Such locks may be engaged to fix the position of the display fixture 10 and disengaged to permit the wheels to roll and the fixture to be moved.

(26) The base 12 of display fixture 10 shown in FIG. 1 supports a first vertical support rail (pillar) 22 and a second vertical support rail (pillar) 24. A top support 23 is coupled at its ends to the tops of pillars 22 and 24. As one skilled in the art will appreciate from FIG. 1, the pillars 22 and 24 may be welded directly to the base or attached to the base 12 via upstanding supports that are welded to the base and mated with open bottoms of the respective pillars 22 and 24. The pillars 22 and 24 may then be bolted to supports using standard bolts of sufficient length together with standard washers and nuts. These nuts, bolts and washers may be eliminated altogether if the supports are long enough and the tolerances between the inside of the pillars 22 and 24 and supports are sufficiently tight to prevent unintentional decoupling of the supports and pillars. Other mechanisms for attaching the pillars to the base 12 may also be employed. The base 12 may also include at least one compartment 16 having an open top and a cover 18 used to close the open top. Two such compartments 16, each having a separate cover 18, are shown in FIG. 4.

(27) The pillars 22 and 24 support a plurality of display panel assemblies. In FIGS. 1-5, three such display panel assemblies 30, 32 and 34 are shown. Two or more than three display panel assemblies may be employed without deviating from the invention. Each display panel assembly 30, 32 and 34 includes at least one display panel, for example, a pegboard display panel 106 of the type shown in FIG. 22 or a grid display panel 108 of the type shown in FIG. 25. The drawings show the panel assemblies 30, 32 and 34 each including two such display panels generically referenced as 42 and 43.

(28) The display panels 42 and 43 are held by a frame 50. Frame 50 includes a first side rail 52, a second side rail 54, and a pair of end rails 56 and 57 extended between and joining the side rails 52 and 54. At least one of the end rails 56/57 may be removable so the display panel(s) 42/43 may be slid in and out of the frame to change the type (e.g., pegboard display panel or grid display panel) or color of display panels held in the frame 50. For example, different color panels may be employed at different times of the year, e.g., greens and pastels in the spring; blues in the summer; browns, yellows and oranges in the fall; reds and greens for the Christmas holiday shopping season; red, white and blue near national holidays such as Independence Day; pink and white near Valentine's Day; etc.

(29) A separate first pivot assembly 60 is employed to couple the side rails 52 of the frames 50 of each panel assembly 30, 32 and 34 to pillar 22. An identical separate second pivot assembly 60 is employed to couple the side rails 54 of frames 50 of each panel assembly 30, 32 and 34 to pillar 24. As such, there is a pair of pivot assemblies associated with each panel assembly, a first pivot assembly for coupling the panel assembly to pillar 22 and a second pivot assembly for coupling the panel assembly to pillar 24.

(30) As best shown in FIG. 7, each pivot assembly 60 includes a bolt 62 having a head 61 and a threaded shaft 63, a plurality of washers 64, a first sleeve 66 adapted to extend through a hole 67 extending through the associated pillar 22/24, a second sleeve 68 adapted to extend through a hole 69 in associated side rail 52/54 of the frame 50, and a nut 70. The threaded shaft 63 of bolt 62 is adapted to pass through the washers 64 and sleeves 66 and 68. The pivot assembly 60 is completed by then threading nut 70 onto threads of threaded shaft 63 of bolt 62 so that the rail of frame 50 is pivotally coupled to the pillar. A slightly modified pivot assembly is shown in FIG. 6.

(31) Those skilled in the art will appreciate that the two pivot assemblies 60 use to attach a panel assembly 30, 32 or 34 to the pillars 22 and 24 are axially aligned along an axis of rotation so that the panel assembly is able to rotate between the vertical position shown, for example, in FIGS. 8-10, and the horizontal position shown, for example, in FIGS. 1, 4 and 11. Since the panel assemblies 30-34 are separately attached to the pillars 22 and 24, they may be selectively and separately pivoted between their respective horizontal positions and vertical positions as exemplified by FIG. 2. In fact, with three such panel assemblies 30, 32 and 34 as shown in FIGS. 1-5, the fixture can be configured in eight different ways as demonstrated in Table 1 below.

(32) TABLE-US-00001 Panel Assembly 30 Panel Assembly 32 Panel Assembly 34 1 Horizontal Horizontal Horizontal 2 Vertical Horizontal Horizontal 3 Vertical Vertical Horizontal 4 Vertical Horizontal Vertical 5 Vertical Vertical Vertical 6 Horizontal Vertical Vertical 7 Horizontal Vertical Horizontal 8 Horizontal Horizontal Vertical

(33) In alternative embodiments using a different number of panel assemblies, the number of possible configurations will change. If there are two panel assemblies, the number of configurations will be four (i.e., 2.sup.2). As additional panel assemblies are added, the number of possible configurations increases exponentially. Representative examples are illustrated in Table 2 below.

(34) TABLE-US-00002 No. of Panels Calculation No. of Configurations 2 2.sup.2 4 3 2.sup.3 8 4 2.sup.4 16 5 2.sup.5 32 6 2.sup.6 64

(35) FIGS. 12 and 13 show an embodiment in which there are eighteen independently operable panels arranged in three columns and six rows. In this embodiment, there are 262,144 possible configurations.

(36) It is important to be able to selectively lock the panel assemblies in both the vertical position and the horizontal position. This may be achieved by using a separate latch assembly or a separate pair of latch assemblies for each of the panel assemblies. For example, a first latch assembly of each pair may be coupled to pillar 22 and a second latch assembly of each pair may be coupled to pillar 24 adjacent the panel assembly 30, 32 or 34 associated with the pair of latch assemblies. In some cases, only one latch assembly per display panel assembly may be necessary.

(37) Latch assembly 80 (see, e.g., FIGS. 5-11) is well suited for use with a panel assembly pivotally mounted so that when the panel assembly is in its horizontal position a portion of the panel assembly projects forward of the pillars 22 and 24 and another portion of the panel assembly projects rearward of the pillars 22 and 24. Each latch assembly 80 comprises a stationary stop such as pin 82 which is coupled to the pillar 22/24 along one of the sides of the pillar 22/24 and below the axis of rotation defined by the pivot assemblies 60 used to couple the panel assembly to the pillars. The stationary pins permanently extend from one of the pillars 22/24 toward the other pillar. Each latch assembly 80 further comprises a retractable stop such as pin 84 coupled to the pillar 22/24 along the opposite side of the pillar 22/24 as the stationary pin 82. Pins 82 and 84 are located at substantially the same height on the pillars 22/24. As shown, the retractable pin 84 is slidably received in a pin housing 86. The pin housing 86 is also provided with a slot 88. A set screw 90 passes through the slot 88 and is turned in a first direction to lock the pin 84 to prevent pin 84 from sliding. The set screw 90 is turned in the opposite direction to unlock the pin 84 and permit it to slide between an extended and a retracted position. The set screw can also be used as a handle to slide the pin 84 in and out when the set screw is turned to the unlocked position.

(38) As shown in FIGS. 8-10 the panel assembly 30 is held in the vertical position by a latch assembly associated with panel assembly 30. Specifically, the stationary stop (e.g., pin 82) of the latch assembly engages a first face 44 of the panel assembly 30 and the retractable stop (e.g. pin 84) engages a second face 46 of the panel assembly 30. More specifically and when two such latch assemblies are used, the side rails 52/54 of the panel assembly 30 are sandwiched between the stationary pins 82 and retractable pins 84 of the pair of latch assemblies 80 associated with panel assembly 30. To unlock the panel assembly 30 from the vertical position, the set screws 90 are loosened allowing the user to slide the retractable pins 84 outwardly so they no longer engage the second face 46 of the panel assembly 30. The panel assembly 30 can then be rotated into the horizontal position shown in FIG. 11. The panel assembly 30 can then be held in the second horizontal position by extending the retractable pins 84 and tightening the set screws 90 to lock the retractable pins 84 in their extended position and in face-to-face registration with the first face 44 of panel assembly 40. As shown in FIG. 11, both the stationary pins 82 and the retractable pins 84 engage the first face 44 of the panel assembly 30 to hold the panel assembly 30 horizontal. The arrangement of the latch assemblies 80 allows the panel assembly 30 to be repeatedly locked and unlocked and, when unlocked, rotated between the first vertical position and the second horizontal position.

(39) Latch assemblies 80 are associated and operate in the same way with respect to panel assemblies 32 and 34 of the display fixture shown in FIGS. 1-5 and with each of the panel assemblies 30-40 of each of the three columns of panel assemblies of the display fixtures shown in FIGS. 12 and 13.

(40) When a selected panel assembly is in the first vertical position, the display panels allow accessories such as hooks, pegs, hangers, baskets or bins to be quickly coupled to the display panels. Examples of such accessories are shown in FIGS. 23-25. It is well known in the art how such accessories are routinely coupled to pegboards 106, grids 108 and other similar panels used in the merchandize display industry. This will not be discussed further here except to note that FIG. 13 shows hooks/hangers 102 attached to each of the eighteen display panels. In the embodiment shown in FIGS. 1-5, hooks 102 and baskets 104 (or other accessories) can be fixed to both display panels 42 and 43. These accessories thus will project in opposite directions from the first face 44 and second face 46 of the panel assembly 40 of the display fixture 10.

(41) After removal of the hooks 102 and other accessories from one or more of the display panel assemblies, one or more of the panel assemblies (30-34 in the case of the embodiment of FIGS. 1 and 30-40 in the case of the embodiment of FIG. 12) may be rotated into the second horizontal position in which the panel assemblies so rotated serve as shelves. See, e.g., FIGS. 1 and 12. When a panel assembly is in the second horizontal position, the panel assembly provides a stable horizontal surface for the display of merchandise.

(42) The display fixtures 10 shown in the drawings further includes one or more compartments 16 in the base 12 for storing accessories such as hooks 102. See FIGS. 2, 4, 5 and 21. Each compartment 16 has a removable cover 18 to enable access to the compartment for placing accessories in the compartment 16 or removing accessories from the compartment 16. The cover 18 is used to close the compartment 16 whenever there is no need to access the accessories and to secure the accessories in the compartment 16.

(43) The display fixtures 10 can easily, quickly and efficiently be converted between various configurations. The display fixture 10 shown in FIGS. 1-5 can also can be easily moved about and locked in place, all by a single person and in less than a minute. Likewise, the display fixtures 10 can by converted without any tools. Display fixtures 10 can be converted without extraneous parts (other than the hooks or other accessories) that are not permanently attached. Even these accessories may be conveniently stored in the compartment(s) 16 when not in use. Thus, no parts should become separated from the display fixture 10 and lost when not in use.

(44) The fixture 10 shown in FIGS. 1-5 is well suited for use in open areas of a retail store where customers and store staff can easily walk around the fixture 10 to place or remove items from either side of the fixture. Similar fixtures offering many of the same advantages, but designed to be positioned against a wall or other vertical surface, may also be provided in accordance with the present invention. The fixture 10 shown in FIGS. 12 and 13 is just one example.

(45) In embodiments such as that of FIGS. 12 and 13, the pillars 22 and 24 will be moved from the center to the rear of base 12 as shown in FIGS. 12-16. Further, the pivot assemblies 60 that couple the panel assemblies 30 through 40 to the pillars 22 through 28 are moved with respect to the panel assemblies 30 through 40 so that the axis of rotation of each of the panel assemblies is immediately adjacent one end (e.g., adjacent end rail 56 or end rail 57) of the panel assembles. See FIGS. 14-16. As such, any of the panel assemblies in the horizontal position will only project forward from the pillars 22 through 28.

(46) Also, the position of the pins of the latch assemblies 80 will be adjusted so that each panel assembly can be (1) supported in the horizontal position, (2) permitted to rotate between the horizontal and vertical positions, and (3) be held in place in the vertical position. In one embodiment shown in FIGS. 14 and 15, the stationary pins 82 are located on the front of the pillars (e.g., 22) so they extend beneath and support the panel assemblies in the horizontal position. The retractable pins 84 are positions higher up on the pillars so that they can engage the frames 50 of the panel assemblies to hold the panel assemblies vertical. A second stationary pin 82 may be added at the same level along the pillar as the retractable pin as shown in FIGS. 14 and 15.

(47) Other modifications can be made without deviating from the invention. For example, the position and number of the pivot assemblies and latch assemblies and their positions on the pillars may be adjustable to accommodate different sizes of panel assemblies and different numbers of panel assemblies. Rather than using latch assemblies having retractable pins that engage a face of a panel assembly, the panel assemblies may include holes in the frame, such as hole 53 in FIG. 16, adapted to receive the retractable pin 84 to lock the panel in place. In the arrangement shown in FIG. 16, the retractable pin 84 extends through the pillar 22 and is aligned with hole 83 when the panel is vertical. The retractable pin 84 is then mated with the hole 83 to latch the display panel assembly (of which frame member 52 is a part) to secure the panel assembly in the vertical position.

(48) The panel assemblies may include a single display panel (such as a sheet of pegboard 106 or a grid 108) or may include two such panels. When two panels are used, one can be of a first style (e.g., a sheet of pegboard 106) and the other can be of a second style (e.g., a grid 108) or both panels can be of the same style. To provide even greater flexibility when setting up a display using the display fixture, the frames 50 of the display panel assemblies may also be designed to hold four panels, e.g., two pegboard panels 106 and two grid panels 108 which may be arranged in the frames of the panel assemblies in alternate ways as illustrated in FIGS. 17-20. As shown in FIG. 18, the two pegboard panels 106 may be positioned on the outside and exposed for use in joining accessories to the to the display panel assembly. As shown in FIG. 19, two grid panels 108 may be positioned on the outside and exposed for use in joining accessories to the display panel assembly. As shown in FIGS. 17 and 20, the pegboard panels 106 and the grid panels 108 may be arranges so that one of the exposed panels is a pegboard panel 106 and the other of the exposed panels grid panel 108. Also, because all four panels are held by the frame, the risk that any of the panels will be lost or misplaced when not in use is virtually eliminated.

(49) Likewise, the shape of the panels and base need not be rectangular as show. They can have essentially any planar geometric shape, such as an oval shape, when viewed from the top.

(50) As shown in FIG. 21, stops 92 may be coupled to the bottom of the base 12. More than one stop may be used even though only one is shown. However, this is unnecessary if the wheel assemblies are not employed (see, e.g., FIGS. 13-16) or if the wheel base is wide enough both front to back and side to side to prevent tipping. The stop 92 shown in FIG. 21 serves to prevent the display fixture 10 from tipping relative to the support surface 1 about the axis of rotation of the wheels. The stops 92 include a lever 94 and a pad 96. The lever 94 is actuatable to lower the pad 96 into engagement with support surface 1. When the pad 96 is in this position, the pad prevents tipping of the display fixture 10 about the axis of rotation of the two wheels of the wheel assemblies 14. The lever 94 is also actuatable to raise the pad 96 slightly off and out of engagement with the support surface 1 so that the display fixture 10 may more easily be transported via the wheels between locations.

(51) From the foregoing, it will also be appreciated that although the specific examples have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit or scope of this disclosure. It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting and that the following claims, including all equivalents, are intended to define the invention.