Title:
Snap-On Leg Rest Mechanism For Furniture Member
Kind Code:
A1


Abstract:
A snap-on leg rest mechanism for a furniture member includes a link having an elongated slot and opposed first and second sides. A polymeric bushing is slidably received in the elongated slot. The bushing includes opposed homogenously joined first and second legs elastically displaceable with respect to each other, the legs defining a U-shape having a shaft receiving aperture therebetween. Opposed first and second bushing wings each abut one of the first and second link sides when the bushing is receiving in the elongated slot. The first wing homogenously extends from a first bushing side and the second wing homogenously extends from a second bushing side. A shaft rotatably received in the shaft receiving aperture is retained by the bushing when the bushing is received in the elongated slot.



Inventors:
Marshall, Richard E. (Monroe, MI, US)
Application Number:
11/831286
Publication Date:
02/05/2009
Filing Date:
07/31/2007
Primary Class:
Other Classes:
297/463.1
International Classes:
A47C1/031
View Patent Images:
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20100078908STROLLER HAVING A SEAT BELT ATTACHMENT AND ADJUSTMENT DEVICEApril, 2010Pos
20090200851HEAD AND/OR NECK SUPPORTAugust, 2009Link
20030094836Folding chair with movable backrest-supporting tubesMay, 2003Chen
20080164737WORKSTATION WITH COMPUTER SYSTEMS AND COMPONENTSJuly, 2008Fowlds et al.
20040174054Patient-relaxing dental chairSeptember, 2004Franke
20080054704Toy Animal for Use with Child TransportationMarch, 2008Friend-douglass
20090127909Control for adjustable backrest of a seat or lounge, and seat or lounge incorporating itMay, 2009Caldwell



Primary Examiner:
GARCIA, ERNESTO
Attorney, Agent or Firm:
HARNESS DICKEY (TROY) (Troy, MI, US)
Claims:
1. A snap-on bushing adapted to rotatably connect a mechanism link of a furniture member to a shaft, comprising: opposed first and second homogenously joined legs that are elastically displaceable with respect to each other, the legs defining a U-shape having a shaft receiving aperture therebetween; and opposed first and second wings adapted to abut opposite sides of a slot formed in the mechanism link, the first wing homogenously extending from a first side of the bushing and the second wing homogenously extending from a second side of the bushing.

2. The snap-on bushing of claim 1, wherein a free end of each of the first and second legs defines a closure arm having an inner radius forming a portion of the shaft receiving aperture.

3. The snap-on bushing of claim 2, wherein the free ends of the first and second legs are adapted to be slidably overlapped with respect to each other to allow the first and second legs to be elastically deflectable toward each other.

4. The snap-on bushing of claim 1, wherein each of the first and second wings extends radially outward with respect to the shaft receiving aperture and defines an arc of curvature of approximately 45 degrees.

5. The snap-on bushing of claim 4, wherein the first and second wings are angularly offset from each other to define a total radius of curvature of approximately 180 degrees.

6. The snap-on bushing of claim 1, wherein the shaft receiving aperture defines an elongated aperture.

7. The snap-on bushing of claim 1, further comprising a raised inner diameter ring radially inwardly extending into the shaft receiving aperture from the first and second legs.

8. The snap-on bushing of claim 1, wherein each of the first and second legs includes a raised portion, the raised portions of the first and second opposed legs facing away from each other.

9. The snap-on bushing of claim 1, comprising a polymeric material.

10. A leg rest device for a furniture member, comprising: a link having an elongated slot created proximate an engagement end and opposed first and second sides; and a polymeric bushing adapted to be slidably received in the elongated slot, the bushing including: opposed homogenously joined first and second legs that are elastically displaceable with respect to each other, the legs defining a U-shape having a shaft receiving aperture therebetween; and opposed first and second wings each adapted to abut one of the first and second sides of the link when the bushing is received in the elongated slot, the first wing homogenously extending from a first side of the bushing and the second wing homogenously extending from a second side of the bushing.

11. The leg rest device of claim 10, further comprising a shaft rotatably received in the shaft receiving aperture and retained by the bushing when the bushing is received in the elongated slot of the link.

12. The leg rest device of claim 11, wherein each of the first and second legs includes a raised portion, the raised portions of the first and second legs facing away from each other.

13. The leg rest device of claim 12, wherein the link further includes first and second recessed slots oppositely positioned about the elongated slot, the first and second recessed slots each adapted to receive one of the first and second raised portions to temporarily lock the bushing within the elongated slot and to temporarily retain the shaft between the first and second legs when the shaft is received in the shaft receiving aperture.

14. The leg rest device of claim 13, further comprising: a free end of each of the first and second legs defining a closure arm having an inner radius forming a portion of the shaft receiving aperture; wherein the free ends of the first and second legs are adapted to be slidably overlapped with respect to each other to allow the first and second legs to be elastically deflectable toward each other to disengage the first and second raised portions from the first and second recessed slots.

15. The leg rest device of claim 11, further comprising: a raised inner diameter ring radially inwardly extending into the shaft receiving aperture from the first and second legs; and a recessed circumferential slot created on the shaft, the slot adapted to receive the raised inner diameter ring to prevent longitudinal displacement of the bushing along the shaft.

16. 16-20. (canceled)

21. A snap-on bushing adapted to rotatably connect a mechanism link of a furniture member to a shaft, comprising: opposed first and second homogenously joined legs that are elastically displaceable with respect to each other, the legs defining a U-shape having a shaft receiving aperture therebetween, each of the first and second legs including a raised portion having an angular face, the raised portion of the first leg facing oppositely away from the raised portion of the second leg; and opposed first and second semi-spherical shaped wings adapted to abut opposite sides of a slot formed in the mechanism link, the first wing homogenously extending from a first side of the bushing and the second wing homogenously extending from a second side of the bushing, each of the first and second wings extending radially outward with respect to the shaft receiving aperture and defining an arc of curvature.

22. The snap-on bushing of claim 21, further comprising a first closure arm extending from a free end of the first leg and a second closure arm extending from a free end of the second leg, the first and second closure arms elastically deflectable toward each other in each of a first arm closure arc and a second arm closure arc.

23. The snap-on bushing of claim 22, wherein the first and second angular faces each comprise an outwardly facing surface defining an angle with respect to a side wall oppositely directed from the closure arm.

24. The snap-on bushing of claim 22, wherein the first and second closure arms each include an inner radius defining a portion of the shaft receiving aperture.

25. The snap-on bushing of claim 22, wherein each of the first and second closure arms define a thickness less than half of a bushing thickness to provide a sliding clearance between the first and second closure arms to permit the first and second legs to be elastically defected toward each other.

Description:

FIELD

The present disclosure relates to leg rest extension mechanisms for articles of furniture including chairs, sofas, and loveseats.

BACKGROUND

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

Conventionally, reclining type articles of furniture (i.e., chairs, sofas, loveseats, and the like) require a mechanism to bias a leg rest assembly in extended and stowed positions. Known mechanisms commonly include a large number of moving parts that tend to increase the manufacturing time and costs associated with the furniture member. Linkage assemblies that provide one or more extended positions of the leg rest assembly are commonly assembled using metal brackets and fasteners to attach the linkage members to a support shaft provided to help extend the leg rest assembly.

Because these parts move to extend and stow the leg rest assembly, the parts require alignment relative to one another and lubrication to ensure proper operation. Moreover, the quantity of parts adds weight making the furniture member more difficult to move and transport. When the connecting parts are metal-to-metal, the moving parts also tend to generate noise as the user extends (or stows) the leg rest assembly.

SUMMARY

According to several embodiments of a snap-on leg rest mechanism for furniture member of the present disclosure, a snap-on bushing adapted to rotatably connect a mechanism link of a furniture member to a shaft includes opposed first and second homogenously joined legs elastically displaceable with respect to each other, the legs defining a U-shape having a shaft receiving aperture therebetween. Opposed first and second wings are adapted to abut opposite sides of the mechanism link. The first wing homogenously extends from a first side of the bushing and the second wing homogenously extends from a second side of the bushing.

According to further embodiments, a snap-on leg rest mechanism for a furniture member includes a link having an elongated slot proximate an engagement end, and opposed first and second sides. A polymeric bushing is slidably received in the elongated slot. The bushing includes opposed homogenously joined first and second legs elastically displaceable with respect to each other, the legs defining a U-shape having a shaft receiving aperture therebetween. Opposed first and second wings are each adapted to abut one of the first and second sides of the link when the bushing is receiving in the elongated slot. The first wing homogenously extends from a first side of the bushing and the second wing homogenously extends from a second side of the bushing. A shaft rotatably received in the shaft receiving aperture is retained by the bushing when the bushing is received in the elongated slot of the link.

According to still further embodiments, a method for engaging a shaft of a leg rest mechanism of a furniture member to a mechanism link includes creating an elongated slot in the link. The method further includes elastically displacing opposed legs of a bushing to position the shaft between the legs, and sliding the bushing with the shaft positioned therein into the elongated slot until the opposed first and second wings of the bushing abut opposed sides of the link.

Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

FIG. 1 is a front perspective view of a furniture member having a snap-on leg rest mechanism member of the present disclosure;

FIG. 2 is a front perspective view of an operating mechanism assembly shown in FIG. 1;

FIG. 3 is a cross-sectional side elevational view of the operating mechanism assembly of FIG. 2;

FIG. 4 is a cross sectional side elevational view of the furniture member operating mechanism at section 4 of FIG. 3 adapted to provide for an extensible leg rest;

FIG. 5 is a front perspective view of a portion of the mechanism at area 5 of FIG. 4;

FIG. 6 is a perspective view of a snap-on device and shaft connected position of the snap-on device of the present disclosure;

FIG. 7 is a front perspective view of the connected position of the snap-on device of FIG. 6 shown prior to installation with a modified link member;

FIG. 8 is a perspective view similar to FIG. 6;

FIG. 9 is a perspective view of the snap-on device of FIG. 6 in the installed position with the modified link;

FIG. 10 is a front perspective view of a snap-on device of the present disclosure;

FIG. 11 is a side elevational view of the snap-on device of FIG. 10;

FIG. 12 is a cross sectional bottom plan view taken at section 12 of FIG. 11;

FIG. 13 is a bottom plan view of the snap-on device of FIG. 11;

FIG. 14 is an end elevational view of the snap-on device of FIG. 11;

FIG. 15 is a cross sectional side elevational view taken at section 15 of FIG. 14;

FIG. 16 is a side elevational view of a modified link of the present disclosure;

FIG. 17 is an end elevational view of the modified link of FIG. 16; and

FIG. 18 is a side elevational view taken at area 18 of FIG. 16.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. The terms “left hand” or “left handed” and “right hand” or “right handed” used herein refer to an occupant seated in the furniture member.

In accordance with the teachings of the present disclosure, a multiple position leg rest member for use in single and multi-person articles of furniture (i.e.: chairs, sofas and/or loveseats) is disclosed. A general understanding of the art to which the present disclosure pertains is disclosed in U.S. Pat. No. 3,325,210, Adjustable Leg Rest Locking Device, U.S. Pat. No. 5,570,927, Modular Wall Proximity Reclining Chair, and U.S. Pat. No. 6,655,732, Multiple Position Leg Rest Mechanism For A Reclining Chair, which are commonly owned by the assignee of the present mechanism and the disclosures of which are expressly incorporated by reference herein. As will be described, the pre-assembled actuation mechanism permits a leg rest assembly to pivot in a 3-position movement from upholstered frame components so as to provide precise mechanical alignment and superior structural rigidity while concomitantly facilitating application of highly efficient fabrication and assembly processes.

With reference to FIGS. 1 and 2, the article of furniture shown is a combination wall proximity recliner and tilt chair, hereinafter referred to as chair 10. A leg rest assembly 12 is extensible in an arc of rotation “A” from a stowed position abutting chair 10 (shown in FIG. 1) to an extended position (shown in FIG. 2) using a hand lever 14 connected to an actuation mechanism 16. In one aspect of the disclosure, hand lever 14 is rotated counterclockwise about an arc of rotation “B” to extend leg rest assembly 12, and can be oppositely rotated to return leg rest assembly 12 from the extended to the stowed position. Actuation mechanism 16 and various upholstered frame components can also be assembled as a modular seating unit. It should be understood, however, that the elements of actuation mechanism 16 and leg rest assembly 12 are not limited to use with chair 10, but are applicable for use in virtually any type of single or multi-person article of furniture. As such, the particular structure of the various sub-assemblies and components which, when assembled, define chair 10 are merely intended to illustrate but one furniture application to which the present disclosure is applicable.

Referring now generally to FIGS. 1 and 3, actuation mechanism 16 includes a drive rod 18 integrated into and rotatably supported from a chair frame 19 and, in particular, from left and right side frame assemblies 20, 22 defining a drive rod axis of rotation 24. Actuation mechanism 16 further includes a front support shaft 25, which together with drive rod 18 are spatially oriented to be located and “suspended” from right and left side frame assemblies 20, 22. In some aspects, drive rod 18 is an elongated square-shaped metal shaft having manually-operable hand lever 14 (shown in FIG. 1) secured thereto proximate an upholstered exterior portion of one of right and left side frame assemblies 20 or 22. Hand lever 14 can therefore be easily reached by an occupant seated in chair 10 for convenient actuation of drive rod 18.

Leg rest assembly 12 is supported for extensible movement using actuation mechanism 16. More specifically, mechanism 16 includes a right and a left pantograph linkage 26, 28 and a spring-assisted toggle assembly 30 which are operably associated with drive rod 18 and front support shaft 25 for permitting the seat occupant to selectively actuate leg rest assembly 12 in response to rotation of drive rod 18 via hand lever 14. Mechanism 16 can also include right and left support shaft mounting brackets 31, 32, and right and left leg rest support brackets 34, 36. In addition to side frame assemblies 20, 22, chair frame 19 can also include a front rail member 38 which, when interconnected, define rigid “box-like” chair frame 19.

A first and a second connecting link 40, 41 help convert the rotational motion of drive rod 18 to longitudinally translate right and left hand pantograph linkages 26, 28. Leg rest assembly 12 is both supported and moved by right and left pantograph linkages 26, 28 and right and left leg rest support brackets 34, 36. In some aspects of the disclosure, right and left pantograph linkages 26, 28 are identical. Right and left pantograph linkages 26, 28 are operably suspended about a set of “fixed” suspension points defined by front support shaft 25. The extensible action of leg rest assembly 12 takes place simultaneously for both the right and left pantograph linkages 26, 28 when there is sufficient angular rotation of drive rod 18 via hand lever 14.

In general, the structural frame components such as side frame assemblies 20, 22 and front rail member 38 are each constructed in a manner which enables them to support springs, padding, upholstery, and the like in order to complete a decorative and stylish chair 10. For example, the upholstery shown in FIG. 1 can be applied to each outward facing side of side frame assemblies 20, 22 and to a forward facing side 42 of front rail member 38. Each frame component is individually preassembled for subsequent modular assembly into chair 10. However, it is to be understood that the specific construction shown for each frame component is merely exemplary in nature.

Referring now to FIG. 4, chair frame 19 can further include a rear rail member 43 which provides additional frame stiffness, an occupant seat support pan or member 44, and at least one occupant back support member 45. Mechanism 16 is connected to each of right and left side frame assemblies 20, 22 which in turn can be supported using a spring assembly 46 between a rocker block 47 connected to each of right and left side frame assemblies 20, 22 and a base assembly 48 which is duplicated on the right side of chair 10. A front frame member 50 can also be provided to structurally support an area from which front rail member 38 is extendable.

Mechanism 16 can further include a bracket 52 which is coupled at one end for rotation by drive rod 18. A left hand portion of mechanism 16 and leg rest assembly 12 will be discussed in greater detail. The right hand portion of mechanism 16 and leg rest assembly 12 is similar. Bracket 52 is rotatably coupled at a second end such as by a fastener or pin to second connecting link 41. Left pantograph linkage 28 is connected to front support shaft 25 using a left drive link 56 having an engagement end 57 coupled to front support shaft 25. Left drive link 56 is rotatably connected to left pantograph linkage 28 using a pin 58.

Referring to FIG. 5, the left hand configuration of leg rest assembly 12 is shown. Second connecting link 41 is rotatably connected to bracket 52 such that rotation of drive rod 18 induces a translation of second connecting link 41. Second connecting link 41 is in turn connected to left pantograph linkage 28. Left drive link 56 is rotatably connected as previously described using pin 58 to left pantograph linkage 28. Left drive link 56 is further rotatably coupled to second connecting link 41 using a pin 59. Pins 58 and 59 can be any type of rotatable connection fastener including a rivet such as a spin rivet. Engagement end 57 of left drive link 56 is connected to front support shaft 25 at a slot 60 created in engagement end 57. A snap-on bushing 62 is disposed within slot 60 which rotatably receives front support shaft 25.

Referring now to FIGS. 6 and 7, bushing 62 can be made by a molding process such as injection molding, of a polymeric material such as but not limited to a polyamide material. Bushing 62 includes each of a first and a second bushing leg 64, 66 homogenously connected to each other such that bushing 62 defines a U-shaped component. First bushing leg 64 is elastically deflectable in a first leg deflection arc “C” and second bushing leg 66 is oppositely elastically deflectable in a second leg deflection arc “D”. Deflection of first and second bushing legs 64, 66 permits a snap-on installation of bushing 62 onto front support shaft 25. Bushing 62 is snapped onto front support shaft 25 in an engagement direction “E” by deflection of first and second bushing legs 64, 66 so that bushing 62 is positioned as shown in FIG. 7 prior to receipt of both bushing 62 and front support shaft 25 within slot 60 of engagement end 57.

Referring now to FIG. 8, according to several embodiments bushing 62 can further include a raised inner diameter ring 68 which extends radially inward into a shaft receiving aperture 70. The shaft receiving aperture 70 defines an oval shaped elongated aperture. When bushing 62 is connected to front support shaft 25, raised inner diameter ring 68 is received within a recessed circumferential slot 72 previously created in front support shaft 25. Engagement of raised inner diameter ring 68 into recessed circumferential slot 72 prevents longitudinal displacement of bushing 62 along front support shaft 25, while also permitting left drive link 56 and bushing 62 to rotate with respect to front support shaft 25. Bushing 62 further includes a first semi-spherical wing 74 and an oppositely positioned and angularly offset second semi-spherical wing 76. When bushing 62 is received in slot 60, first semi-spherical wing 74 abuts a first link face 78 of left drive link 56. At the same time, second semi-spherical wing 76 abuts or is positioned proximate to second link face 80 of left drive link 56. First and second semi-spherical wings 74, 76 help prevent lateral displacement of bushing 62 with respect to left drive link 56, and both bushing 62 and left drive link 56 with respect to front support shaft 25. A spacing between each of first and second semi-spherical wings 74, 76 is equal to or greater than a link thickness “F” of left drive link 56.

Bushing 62 can further include a first raised portion 82 created on first bushing leg 62 and a second raised portion 84 created on second bushing leg 66. First and second raised portions 82, 84 are each received within a first and second recess slot 86, 88 created in left drive link 56 on opposite sides of slot 60. First and second raised portions 82, 84 help prevent displacement of front support shaft 25 out of slot 60 when the installation of bushing 62 is completed.

Referring now to FIG. 9, an installed condition of bushing 62, left drive link 56, and front support shaft 25 is shown. The installed condition includes engagement of first and second raised portions 82, 84 in each of first and second recess slots 86, 88. The elastic outward displacement of first and second bushing legs 64, 66 when bushing 62 is engaged about front support shaft 25 helps retain the engagement of first and second raised portions 82, 84 in first and second recess slots 86, 88. If it is desired that bushing 62 and left drive link 56 be removed from front support shaft 25, bushing 62 further includes a first closure arm 90 extending from a free end of first bushing leg 64 and a second closure arm 92 extending from a free end of second bushing leg 66. First and second closure arms 90, 92 can be elastically deflected toward each other in each of a first arm closure arc “G” and a second arm closure arm arc “H”. This deflection allows first and second raised portions 82, 84 to be displaced out of first and second recess slots 86, 88. First and second closure arms 90, 92 when positioned as shown in FIG. 9 curve partially around front support shaft 25 to normally prevent disengagement of front support shaft 25 from slot 60.

Referring to FIG. 10, first closure arm 90 is directed toward second bushing leg 66 and second closure arm 92 is directed toward first bushing leg 64. Each of first and second closure arms 90, 92 are less than half the thickness of bushing 62 to provide at least a sliding clearance between the first and second closure arms 90, 92 to permit first and second bushing legs 64, 66 to be elastically defected toward each other for removal of front support shaft 25.

Referring now to FIGS. 11 through 13, shaft receiving aperture 70 defines an elongated aperture which allows a sliding motion of front support shaft 25 within shaft receiving aperture 70. This limits the contact area between front support shaft 25 and the inner wall defined by shaft receiving aperture 70 to reduce friction during rotation of left drive link 56. Each of the first and second semi-spherical wings 74, 76 can define an arc of approximately 45 degrees (which can vary at the discretion of the manufacturer from approximately 10 degrees to approximately 75 degrees inclusive) having a wing outer radius “J”. The first and second semi-spherical wings 74, 76 are angularly offset from each other and can define an approximately 180 degree total radius of curvature as viewed in FIG. 11. Distal ends of first and second raised portions 82, 84 are positioned at a spacing dimension “K” from a first center of shaft receiving aperture 70. Bushing 62 includes a bushing total height “L”, a bushing total width “M”, an arm swing clearance dimension “N” in a non-deflected state, a separation distance “P” between first and second semi-spherical wings 74, 76 and also between each of an extending portion 94 and an extending portion 96, a thickness “Q” of each of first and second semi-spherical wings 74, 76, an aperture diameter “R” of shaft receiving aperture 70, and a bushing total depth “S”.

According to several embodiments, wing outer radius “J” can be approximately 0.375 in (0.95 cm), spacing dimension “K” can be approximately 0.313 in (0.79 cm), bushing total height “L” can be approximately 0.813 in (2.06 cm), bushing total width “M” can be approximately 0.75 in (1.90 cm), and arm swing clearance dimension “N” can be approximately 0.343 in (0.87 cm). In addition, separation distance “P” can be approximately 0.135 in (0.34 cm), thickness dimension “Q” can be approximately 0.063 in (0.16 cm), aperture diameter “R” can be approximately 0.5 in (1.27 cm), and bushing total depth “S” can be approximately 0.26 in (0.66 cm). These dimensions are provided to define an exemplary embodiment of the present disclosure and can be modified at the discretion of the manufacturer to suit various embodiments of actuation mechanism 16 and diameters of front support shaft 25.

Referring now to FIGS. 14 and 15, according to several embodiments, second semi-spherical wing 76 can be positioned at a spacing dimension “T” with respect to a first side 95 of bushing 62. The first semi-spherical wing 74 homogenously extends from first side 95 of bushing 62 and the second semi-spherical wing 76 homogenously extends from a second side 97 of bushing 62. Bushing 62 can further include angular faces 98, 99 each defining an outwardly facing surface of one of the first and second raised portions 82, 84. Angular face 98 defines an angle α with respect to a side wall 100 oppositely directed from first closure arm 90. According to several embodiments, angle α can be approximately 21.6 degrees which can vary from approximately 10 degrees to approximately 45 degrees inclusive at the discretion of the manufacturer. Angular face 99 is created as a mirror image of angular face 98 and therefore is also oriented at angle α similar to angular face 98. The closure arms 90, 92 each have an inner radius 101 forming a portion of the shaft receiving aperture 70. In an as-molded or non-deflected condition of bushing 62, first and second closure arms 90, 92 are separated from each other by an arm spacing dimension “U” which in several embodiments can be approximately 0.06 in (0.15 cm).

Referring to FIGS. 16 and 17, left drive link 56 includes first and second legs 102, 104 which are oriented at an angle β with respect to each other. According to several embodiments, angle β is approximately 147.5 degrees, which can vary from approximately 90 degrees to approximately 170 degrees inclusive depending on the necessary geometry of the mechanism. First leg 102 has a first leg width “V” which according to several embodiments can be approximately 1.124 in (2.85 cm), and second leg 104 has a second leg width “W” which according to several embodiments can be approximately 1.324 in (3.36 cm). Second leg 104 can be wider than first leg 102 to provide additional stiffness at engagement end 57 due to the elimination of material associated with slot 60.

A first pin receiving aperture 106 and a second pin receiving aperture 108 are created in first leg 102 to receive each of pins 58 and 59 described in reference to FIG. 5. First leg 102 can also have a radius end 110. Second leg 104 can include a radius end 112, and slot 60 can include a hemispherical wall 114 defining a closed end of slot 60.

According to several embodiments, an aperture spacing dimension “X” between first and second pin receiving apertures 106, 108 can be approximately 1 in (5.36 cm), and a spacing dimension “Y” between a center axis of first pin receiving aperture 106 and a center axis of slot 60 can be approximately 6.75 in (17.1 cm). A total link length “Z” can be approximately 7.82 in (19.86 cm). An aperture-to-slot separation dimension “AA” can be approximately 2.34 in (5.94 cm), and a total link height “BB” can be approximately 3.45 in (8.76 cm). Left drive link 56 can have a link total thickness “CC” of approximately 0.112 in (0.28 cm). The dimensions identified for left drive link 56 can similarly be provided for a right drive link 54 (not shown) and are provided as exemplary dimensions only as the overall dimensions of right and left drive links 54, 56 can vary with the geometry of actuation mechanism 16.

Referring now to FIG. 18, slot 60 has a width which is defined as two times a hemispherical slot spacing dimension “DD”, which according to several embodiments can be approximately 0.315 in (0.80 cm). Slot 60 further defines an angle θ between a slot wall 116 and a link edge 118 which according to several embodiments is approximately 45 degrees, and can vary from approximately 20 degrees to approximately 70 degrees inclusive at the discretion of the manufacturer. Each of first and second recess slots 86, 88 are also positioned at a recess slot spacing dimension “EE” from an axis of curvature defining hemispherical wall 114. According to several embodiments, recess slot spacing dimension “EE” can be approximately 0.218 in (0.55 cm).

A snap-on leg rest mechanism of the present disclosure offers several advantages. By using a snap-on bushing 62 engaged within a slot 60 of a left drive link 56, the left drive link 56 can be connected to the front support shaft 25 of an actuation mechanism 16 using a snap-on plastic part in place of a previously known bearing assembly which required lubrication. Bushing 62 of the present disclosure does not require lubrication after installation and provides a less expensive and lower noise producing part. Further, bushing 62 is connected to the shaft by elastically deforming the bushing legs, therefore no fasteners are required to assemble bushing 62 with the drive link. Bushing 62 is also removable by elastically deforming each of the bushing legs 64, 66 in a direction opposite to that used in connecting bushing 62 to the shaft.