HK1081414B - Multiple position leg rest mechanism for a reclining chair - Google Patents

Description

Multi-position leg rest mechanism for reclining chair

Background

The present invention relates generally to reclining chairs and, more particularly, to a three-position leg rest mechanism for a reclining chair.

Traditionally, reclining chairs are equipped with an actuation mechanism that is operatively interconnected between a prefabricated chair frame and a stationary base assembly. The actuation mechanism is typically a combination of various mechanical linkages that may be operable to provide various comfort features, such as independent reclining movement of the seat assembly, as well as actuation of the extendable leg rest assembly and associated tilting of the chair frame.

While many conventional reclining chairs operate satisfactorily, furniture manufacturers are continually seeking to develop improved frames and actuation mechanisms for reducing the complexity of the system, increasing the smoothness of operation, and comfort of the seated user. In addition, there is a continuing need to develop improved manufacturing and assembly techniques that will result in reduced costs while promoting increased efficiency and improved product quality.

Summary of the invention

In accordance with the principles of the present invention, an improved leg rest mechanism is disclosed that is relatively simple and inexpensive to manufacture, relatively durable and relatively easy to maintain as compared to conventional leg rest mechanisms. The improved leg rest mechanism is readily adapted for use with conventional actuation mechanisms.

According to a preferred embodiment, a reclining chair is provided which includes an improved multi-position leg rest mechanism which can be placed in a retracted position, a first intermediate position or partially extended position, a second intermediate position and a fully extended position.

Other objects, advantages and features of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings.

Description of the drawings

FIG. 1 is an exploded perspective view of a wall proximity reclining/tilt chair according to the present invention;

FIG. 2 is a perspective view of the inner frame of the wall proximity reclining/tilt chair of FIG. 1;

FIG. 3 is an enlarged perspective view of the actuation mechanism shown in FIG. 2;

FIG. 4 is an enlarged perspective view of the improved three-position actuation mechanism shown in FIG. 3;

FIG. 5 is an exploded perspective view of the improved three position actuation mechanism shown in FIG. 4;

FIG. 6 is an enlarged perspective view of another embodiment of the improved three position actuation mechanism shown in FIG. 3;

FIG. 7 is an enlarged perspective view of the alternate embodiment shown in FIG. 6; and

fig. 8 is an enlarged perspective view of the sector ratchet plate shown in fig. 7.

Detailed description of the invention

In accordance with the teachings of the present invention, an actuation mechanism for use in single or multi-person articles of furniture, such as chairs and sofas or loveseats, is disclosed. General knowledge of the art to which the present invention pertains is disclosed in U.S. patent No.3325210 (adjustable leg rest latch) and U.S. patent No.5570927 (modular wall proximity recliner), which are commonly owned by the assignee of the present invention, the disclosures of which are expressly incorporated herein by reference. As will be described, the preassembled actuation mechanism is uniquely suspended from a pre-upholstered box frame component on a fixed three-pivot structure to provide precise mechanical alignment and superior structural rigidity while concomitantly facilitating the use of efficient manufacturing and assembly processes.

Referring to fig. 1, an article of furniture is shown which is a combination wall proximity recliner and tilt chair, hereinafter referred to as wall proximity reclining/tilt chair 10, which includes a pre-assembled actuation mechanism 12 and various upholstered frame components which can be quickly and easily assembled as a modular seating unit. This "modular" construction provides a significant advance over conventional furniture manufacturing and assembly techniques because there is no longer a need to manipulate a bulky "unitized" chair frame when upholstered. In this manner, each frame component or frame subassembly may be upholstered prior to modular assembly with the actuating mechanism 12 to improve the quality of the individual components and the overall system, as well as production efficiency. Furthermore, due to the compact size of the actuation mechanism of the present invention, it is possible to use soft upholstered cushions, which is an important feature when selling various styles of chair, sofa or loveseat furniture. It should be understood, however, that the various improvements now incorporated into actuation mechanism 12 are not limited to use with reclining/tipping chair 10, but may be used in virtually any type of single or multi-person article of furniture. As such, the particular structure of the various subassemblies and components that define the reclining/tilt chair when assembled is merely illustrative of one furniture application to which the present invention may be applied.

In accordance with the principal design features of the present invention, various pre-assembled and upholstered frame components are now described that are provided for the operatively suspended actuation mechanism in reclining/tilt chair 10. Figure 2 shows the various pre-assembled frame components, with their cushioning, padding, springs, etc., removed to better illustrate the mutual independence of the frame component structures, which can be quickly and rigidly assembled in an easier and efficient manner. In this way, all frame components can be individually manufactured and sub-assembled to include the necessary brackets, springs, padding and cushioning on an already "off-line" batch-wise base. Thereafter, the individual pre-assembled and upholstered frame components are assembled to integrally incorporate the actuating mechanism 12 therein. As noted, while the disclosure hereinafter is primarily directed to wall proximity reclining/tilt chair 10, it should be recognized that the novel modular construction and assembly methods taught by the present invention can be readily incorporated into wall proximity sofas, loveseats, and the like.

As best seen in fig. 2, the actuating mechanism 12 of the wall proximity reclining/tilt chair 10 is incorporated into and operatively suspended from the chair frame 20, and in particular from the left and right side frame assemblies 24. In addition to side frame assemblies 24, chair 10 includes a front rail assembly 26 and a rear rail 28 that, when interconnected, define a "box-like" chair frame. A plurality of structural frame components, such as side frame assemblies 24, front rail assembly 26, and rear rail 28, are preferably each configured in a manner that enables them to support springs, padding, upholstery, etc. to complete a cushioned and stylish reclining/tilting chair 10. As previously indicated, each frame component may be individually pre-assembled for subsequent modular assembly into a wall proximity reclining/tilt chair 10. It should be understood, however, that the particular structure shown for each frame member is merely exemplary.

Referring to fig. 2 and 3, actuation mechanism 12 is shown to include a drive rod 30 and front support shaft 32, both of which are spatially oriented to be precisely positioned and "suspended" from left and right side frame assemblies 24. In the preferred construction, drive rod 30 is an elongated square shaft having a manipulable handle 38 (see FIG. 1) secured thereto adjacent the upholstered exterior of one of side frame members 24 and which is readily accessible for convenient actuation thereof by a person seated in chair 10. Further, leg rest assembly 16 is supported for extension movement on actuation mechanism 12, as shown in fig. 1. More specifically, leg rest assembly 16 includes left and right pantograph linkages 34 and a spring-assisted toggle assembly 36 operatively associated with drive rod 30 and front support shaft 32 to allow a seat occupant to selectively actuate leg rest assembly 16 via the handle in response to rotation of drive rod 30.

Leg rest assembly 16 is supported and moved by the same left and right hand pantograph linkages 34. A conventional pantograph linkage 34 is operatively suspended at a second set of "fixed" suspension points defined by support shaft 32. With sufficient angular rotation of drive rod 30 via handle 38, the extension action of leg rest assembly 16 is simultaneous for both left and right hand pantograph linkages 34. Referring to fig. 3, an exemplary configuration of spring-assisted toggle assembly 36 is shown that works in concert with leg rest pantograph linkage 34 for securely holding leg rest assembly 16 in a fully retracted position against front rail assembly 26. Toggle assembly 36 is also operable to provide a spring force for biasingly urging leg rest assembly 16 toward one of its extended and retracted positions. Additional details regarding the pantograph linkage 34 and the bell crank assembly 36 may be found in U.S. patent No.5570927, the disclosure of which is expressly incorporated herein by reference.

In accordance with the particular embodiment shown in fig. 4 and 5, a ratchet-type escapement mechanism 40 interconnects drive rod 30 and support shaft 32 for providing various locking positions for leg rest assembly 16 between its "stowed" or retracted position and its "extended" position. Detent mechanism 40 typically provides three different locking positions for leg rest assembly 16, which may be established independently of the recumbent/tilted position of chair 10.

Detent mechanism 40 includes a sector assembly 44 having a square aperture 46 formed therethrough to receive drive rod 30 so as to be supported for rotation thereon. An inclined link 42 extends generally between drive rod 30 and front support shaft 32 in a manner to be described hereinafter. The sector assembly 44 includes a pair of sector plates 48 having an arcuate peripheral edge bounding the first cam 52, a pair of locking recesses 54a, 54b, a second cam 55 and an aperture 56 formed therethrough. Sector assembly 44 further includes a spacer plate 58 disposed between the pair of sector plates 48. A pivot pin 60 extends through the rear end of the inclined link 42 and is received in the aperture 56 such that the sector plate 48 is pivotally supported on the inclined link 42. An L-shaped guide slot 62 having a longitudinal leg 62L and a transverse leg 62t is formed in the inclined link 42 forward of the pivot pin 60 and receives a floating catch pin 64.

As best seen in fig. 4, when assembled, sector assembly 44 is supported on drive rod 30 for rotation therewith, while inclined link 42 is pivotally coupled to sector assembly 44 by pivot pin 60. The floating detent pin 64 engages the arcuate peripheral edge 50 of the sector plate 48. A biasing mechanism or pair of tension springs 66 extend between the pivot pin 60 and the detent pin 64 to bias the detent pin 64 rearwardly toward the pivot pin 60.

The forward end of the inclined link 42 has an aperture 68 formed therethrough. A wire suspension member 70 extends from the front support shaft 32 and has a free end received in the aperture 68 of the inclined link 42. A position locking member 72 extends through front support shaft 32 for positioning and retaining wire suspension member 70 on front support shaft 32. A similar retaining member 74 positions and retains the sector assembly 44 on the drive rod 30.

In operation, the actuation mechanism 12 and leg rest assembly 16 are in the retracted position and the detent pin 64 is disposed in the longitudinal leg 62l via the first cam 52. As drive rod 30 is rotated to extend leg rest assembly 16 from the retracted position, sector assembly 44 is also rotated, causing detent pin 64 to traverse circumferential edge 50 of sector plate 48. When the recess 54a is encountered, the tension spring 66 engages the longitudinal leg 62l, seating the detent pin 64 in the recess 54 a. Reverse rotation of drive rod 30 is prevented so that actuating mechanism 12 is in the first intermediate position, which is almost one-third extended. Further rotation of the drive rod 30 overcomes the biasing force of the tension spring 66, causing the detent pin 64 to jump out of the recess 54a and into the recess 54 b. The subsequent counter-rotation of drive rod 30 is again prevented so that leg rest assembly 16 is in a second intermediate position, almost two-thirds extended. Further rotation of drive rod 30 moves detent pin 64 out of recess 54b until it engages second cam 55. In this position, the leg rest assembly 16 is fully extended and the second cam 55 pushes the detent pin 64 forwardly and upwardly into the transverse leg 62t of the L-shaped guide slot 62. In this way, the catch pin 64 disengages from the circumferential edge 50 of the sector plate 48 so that reverse rotation of the drive rod 30 is not prevented by the catch pin 64 acting on the recesses 54a, 54b formed in the circumferential edge 50. Reverse rotation of drive rod 30 returns leg rest assembly 16 to its fully retracted position. When leg rest assembly 16 returns to its retracted position, sector assembly 44 rotates relative to inclined link 42 and first cam 52 engages detent pin 64, readjusting its position into longitudinal leg 62 l. A tension spring 66 urges the detent pin 64 rearwardly in the guide slot 62 into biasing relation with the circumferential edge 50 of the sector plate 48. Thus, the escapement is readjusted.

From the above description, it will be appreciated that when detent pin 64 is locked, biased toward one of recesses 54, leg rest assembly 16 is released, locked into the corresponding raised position by detent mechanism 40 preventing inadvertent retraction. Further, leg rest assembly 16 can only be returned to its retracted position from an intermediate position by first fully extending leg rest assembly 16.

Escapement 40 is designed to fail before any other components of actuating mechanism 12 fail due to misuse or overloading. Replacement of escapement 40 requires partial disassembly of the chair and removal of drive rod 30. Thus, another embodiment of detent mechanism 40 is shown in FIGS. 6, 7 and 8, which is suitable for use with actuating mechanism 12 and which facilitates replacement of detent mechanism 40 without requiring disassembly of the chair or removal of drive rod 30.

Referring now to fig. 6, 7 and 8, detent mechanism 40 'is substantially identical to detent mechanism 40, except for modifications relating to the securement of sector plate 48' to drive rod 30. More specifically, the square hole 46 'of the sector plate 48' extends away from the circumferential edge 50 'that engages the detent pin 64 to form a cutout 76 in the sector plate 48'. The spacer plate 58 is replaced with a spacer plate 58 'to maintain proper spacing between the two sector plates 48'. Spacer plate 58 ' includes a locking edge 80 that slidably engages a retaining notch 82 of sector plate 48 ' and retains sector plate 48 ' on drive rod 30. Retaining member 74 'is used to position sector assembly 44' on drive rod 30. Operation of detent mechanism 40' of the alternative embodiment is substantially similar to operation of detent mechanism 40.

The foregoing discussion discloses and describes exemplary embodiments of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims, that various changes, modifications and variations can be made therein without departing from the spirit and scope of the invention as defined in the following claims.

Claims (18)

1. A leg rest positioning mechanism for use in an actuation mechanism of the type having a drive rod and a front support shaft for releasably positioning a leg rest assembly in a retracted position, an extended position and at least one intermediate position, said leg rest positioning mechanism comprising:

a canted link having a pivot pin extending therethrough at a first end, an L-shaped guide slot formed through said canted link adjacent said pivot pin, a second end of said canted link coupled to the front support shaft;

a sector assembly including a pair of sector plates disposed one on each side of said inclined link and rotatably supported on said pivot pin, and a spacer plate disposed between each of said sector plates, each of said sector plates being coupled to the drive rod for common rotation therewith and having a circumferential edge with a first cam, a second cam and at least one recess formed in the sector plate;

a detent pin received in said L-shaped guide slot and engaging said circumferential edge of said sector plate;

a biasing mechanism for biasing said detent pin into engagement with said circumferential edge;

wherein the first cam positions the detent pin in a longitudinal portion of the L-shaped guide slot when the leg rest assembly is in the retracted position, the detent pin engages the at least one recess when the leg rest assembly is in the intermediate position, and the second cam positions the detent pin in a transverse portion of the L-shaped guide slot when the leg rest assembly is in the extended position.

2. The leg rest positioning mechanism of claim 1 wherein the biasing mechanism comprises a spring disposed on each side of the inclined link, each spring extending between the pivot pin and the detent pin.

3. The leg rest positioning mechanism of claim 1 wherein the peripheral edge has a first recess and a second recess formed therein, the detent pin engaging the first recess when the leg rest assembly is extended by about one-third and the detent pin engaging the second recess when the leg rest assembly is extended by about two-thirds.

4. The leg rest positioning mechanism of claim 1 wherein each of said sector plates has a square aperture formed therethrough for receiving said drive rod having a square cross section.

5. The leg rest positioning mechanism of claim 1, wherein the sector assembly further comprises a retaining element for positioning and securing each of the sector plates and the spacing plate on the drive rod.

6. The leg rest positioning mechanism of claim 1 wherein each of said sector plates has a slot formed therein for receiving said drive rod having a square cross section, and said spacer plate secures each of said sector plates to said drive rod for common rotation therewith.

7. The leg rest positioning mechanism of claim 6, wherein the sector assembly further comprises a retaining element for positioning and securing each of the sector plates and the spacing plate on the drive rod.

8. The leg rest positioning mechanism of claim 1 further comprising a hanger extending from the second end of the inclined link, the hanger coupling the inclined link to the front support shaft.

9. An actuation mechanism for a chair having a retractable leg rest assembly, comprising:

a drive rod and a front support shaft;

a pantograph linkage operatively associated with said drive rod and a footrest secured to one end of said pantograph linkage for coordinated hinged movement between a retracted position, an intermediate position and an extended position in response to rotation of said drive rod;

a leg rest positioning mechanism comprising:

a canted link having a pivot pin extending therethrough at a first end, an L-shaped guide slot formed through said canted link adjacent said pivot pin, a second end of said canted link coupled to said front support shaft;

a sector assembly including a pair of sector plates disposed one on each side of said inclined link and rotatably supported on said pivot pin, and a spacer plate disposed between each of said sector plates, each of said sector plates being coupled to said drive rod for common rotation therewith and having a circumferential edge with a first cam, a second cam and at least one recess formed in the sector plate;

a detent pin received in said L-shaped guide slot and engaging said circumferential edge of said sector plate;

a biasing mechanism for biasing said detent pin into engagement with said circumferential edge;

wherein the first cam positions the detent pin in a longitudinal portion of the L-shaped guide slot when the footrest is in the retracted position, the detent pin engages the at least one recess when the footrest is in the intermediate position, and the second cam positions the detent pin in a transverse portion of the L-shaped guide slot when the footrest is in the extended position.

10. The actuating mechanism of claim 9 wherein said biasing mechanism includes a spring disposed on each side of said inclined link, each said spring extending between said pivot pin and said detent pin.

11. The actuating mechanism of claim 9, wherein said peripheral edge has a first recess and a second recess formed therein, said detent pin engaging said first recess when said footrest is extended by about one-third, and said detent pin engaging said second recess when said footrest is extended by about two-thirds.

12. The actuator mechanism of claim 9 wherein each of said sector plates has a square aperture formed therethrough for receiving said drive rod having a square cross section.

13. The actuator mechanism of claim 9 wherein said sector assembly further comprises a retaining element for locating and securing each of said sector plates and said spacer plate on said drive rod.

14. The actuator mechanism of claim 9 wherein each of said sector plates has a slot formed therein for receiving said drive rod having a square cross section, and said spacer plate secures each of said sector plates to said drive rod for common rotation therewith.

15. The actuator mechanism of claim 14 wherein said sector assembly further comprises a retaining element for locating and securing each of said sector plates and said spacer plate on said drive rod.

16. The actuator mechanism of claim 9, further comprising a hanger extending from said second end of said angled link, said hanger coupling said angled link to said front support shaft.

17. The actuating mechanism of claim 9, further comprising a bell crank assembly operatively coupled between said drive rod and said front support shaft for maintaining said shoe plate in a fully retracted position.

18. The actuator mechanism of claim 17 wherein said bell crank assembly is operably coupled between said drive rod and said front support shaft to create a biasing force urging said pantograph linkage toward said retracted position and said extended position.