Wall proximity reclining chair

Information

  • Patent Grant
  • 5992930
  • Patent Number
    5,992,930
  • Date Filed
    Tuesday, May 13, 1997
    27 years ago
  • Date Issued
    Tuesday, November 30, 1999
    25 years ago
Abstract
A reclining chair is provided which includes a base, and a support linkage assembly pivotally supported from the base. A longitudinal link is operably interconnected to the support linkage assembly. A recline linkage assembly is operably coupled to the longitudinal link and to the base for controlling movement of the longitudinal link from an upright position to at least one reclined position. A rotatable drive shaft is journally supported by the longitudinal link. The reclining chair further includes a leg rest assembly supported from the longitudinal link and operably coupled to the drive shaft for movement from a retracted position to an extended position in response to rotation of the drive shaft.
Description

BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates generally to a mechanism for a reclining article of furniture. More specifically, the present invention relates to an all linkage wall proximity reclining mechanism.
2. Description of Related Art
Wall proximity reclining chairs are known within the art, and are becoming increasingly popular as it becomes more desirable to integrate comfort and reclining functions into various articles and styles of furniture including chairs, love seats and sofas. Many of the first developed designs were based upon all linkage mechanisms. However, these all linkage mechanisms typically did not provide a smooth reclining motion. To overcome this problem, wall proximity reclining mechanisms utilizing track and roller assemblies were developed to provide a smoother reclining motion. Presently, the reclining mechanisms utilizing track and rollers are fairly complex, require an excessive number of links, and are thus expensive to manufacture.
An exemplary reclining chair mechanism which was developed to provide a smoother reclining motion is that disclosed in U.S. Pat. No. 5,011,220, entitled "Chair Mechanism," which is expressly incorporated herein by reference, and which is commonly owned by the assignee of the present invention. This mechanism utilizes a short inclined track and roller to provide the recline-away motion of the wall proximity reclining chair. While this chair mechanism achieved the goal of providing smoother reclining operation, the design of this mechanism presents several disadvantages. First, this mechanism is limited to only two operative positions, namely the upright position, and the fully-reclined position. Additionally, this chair design does not allow the chair arms to move along with the seat assembly. Thus, this chair design requires a chair frame having more forwardly extending arm rests for providing adequate support when the chair mechanism is in the fully reclined position.
Another exemplary wall proximity reclining chair is that disclosed in U.S. Pat. No. 5,217,276, entitled "Chair Mechanism," which is also expressly incorporated herein by reference, and which is commonly owned by the assignee of the present invention. This chair mechanism design provides several improvements over those mechanisms known within the art. However, this mechanism also relies upon a track and roller system for providing smooth reclining motion. Additionally, this chair is limited to only two reclining positions, and requires manual actuation via a hand operated lever. Accordingly, this design limits the types of furniture within which this mechanism can be integrated.
Yet another type of wall proximity reclining chair is that illustrated in U.S. Pat. No. 5,323,526, entitled "Method for Assembling A Modular Wall Proximity Reclining Chair," which is expressly incorporated herein by reference, and which is commonly owned by the assignee of the present invention. This chair was developed for reducing the complexity of the reclining mechanism, and the method for assembling the reclining mechanism. This chair mechanism surmounted the disadvantages of the prior art designs by providing a side frame and arm rest assembly that moves in conjunction with the seat assembly for providing adequate arm rest support. However, this mechanism design also relies upon a full length track and roller assembly for providing the desired smoothness in the reclining operation. The requirement for a bearing based roller assembly also increases the cost of the mechanism. Additionally, the design of this mechanism limits this chair to a single reclining chair and further prevents this mechanism from being used in larger articles of furniture, such as loveseats, sofas and modular sofa assemblies.
The all linkage reclining chair mechanisms known within the art also do not provide adequate adjustment features for accommodating seat occupants of varying stature. In view of the growing popularity of wall proximity chairs, there is an increasing need to develop a wall proximity reclining chair mechanism which can be utilized with various types of furniture at a considerably lower cost and that provides the comfort features demanded by consumers. As such, it is desirable to provide an all linkage wall proximity reclining chair which delivers smooth reclining motion and includes an adjustment feature for accommodating various sized seat occupants. It is also desirable to provide an all linkage reclining chair mechanism which is designed to be primarily gravity driven with the assistance of a spring biasing mechanism, rather than manually driven by the occupant using an externally mounted operating handle. Such a design would simplify the operation of the chair. It is also desirable to provide a wall proximity reclining chair mechanism in which the leg rest assembly can be fully extended by actuating a compact trigger release assembly, and can be retracted by the occupant merely moving the leg rest assembly back into the chair mechanism by leaning forward and placing a small amount of force onto the leg rest assembly. Finally, it is desirable to provide a reclining mechanism in which the leg rest assembly can be replaced in the field, if damaged during use, without disassembling the entire chair mechanism.
SUMMARY OF THE INVENTION
In accordance with the principles of the present invention, an all linkage wall proximity reclining chair is disclosed which can be readily incorporated into several different types of furniture. The reclining chair includes a base, and a support linkage assembly pivotally supported from the base. A longitudinal link is operably interconnected to the support linkage assembly. A recline linkage assembly is operably coupled to the longitudinal link and to the base for controlling movement of the longitudinal link from an upright position to at least one reclined position. A rotatable drive shaft is journally supported by the longitudinal link. The reclining chair further includes a leg rest assembly supported from the longitudinal link and operably coupled to the drive shaft for movement from a retracted position to an extended position in response to rotation of the drive shaft.
Additional objects, advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.





DESCRIPTION OF THE DRAWINGS
FIGS. 1A through 1C are perspective views of an exemplary wall proximity reclining chair showing the various operative positions, including an upright position with the leg rest assembly retracted, a partially reclined position with the leg rest assembly fully extended, and a fully reclined position with the leg rest assembly extended and the seat back fully reclined;
FIG. 2 is an outside elevational view of an all linkage assembly in accordance with a preferred embodiment of the present invention with the upholstery, springs and other parts removed from the reclining mechanism for illustrating the integrated and inter-dependent association of the linkage components;
FIG. 3 is an inside elevational view of the all linkage mechanism shown in the upright position in accordance with a preferred embodiment of the present invention;
FIG. 4 is an outside elevational view of the all linkage mechanism in the partially reclined position in accordance with a preferred embodiment of the present invention;
FIG. 5 is an inside elevational view of the all linkage mechanism in the partially reclined position in accordance with a preferred embodiment of the present invention;
FIG. 6 is an outside elevational view of the all linkage mechanism shown in the fully reclined position;
FIG. 7 is an inside elevational view of the all linkage mechanism shown in the fully reclined position, also in accordance with a preferred embodiment of the present invention;
FIG. 8 is a top plan view showing the left and right all linkage assemblies interconnected with various cross members in accordance with a preferred embodiment of the present invention;
FIG. 9 is a perspective view showing the spring assist drive linkage in accordance with a preferred embodiment of the present invention;
FIG. 10 is a top view of the adjustable seat slide mechanism in accordance with a preferred embodiment of the present invention;
FIG. 11 is a partial side elevational view of the adjustable seat slide mechanism, also in accordance with a preferred embodiment of the present invention;
FIG. 12A is a side view of the cable release assembly in the retracted or locked position, in accordance with a preferred embodiment of the present invention;
FIG. 12B is a side view of the cable release assembly in the fully released position, also in accordance with a preferred embodiment of the present invention; and
FIG. 12C is an exploded perspective view of the trip link assembly in accordance with the present invention.





DETAILED DESCRIPTION OF THE INVENTION
In accordance with the teachings of the present invention, an all linkage wall proximity reclining chair adapted for use in various articles of motion furniture is disclosed. In a preferred embodiment, a pair of all linkage mechanisms are integrated into a loveseat in which both sides independently recline. However, it should be understood that the all linkage mechanisms of the present invention can be incorporated into a variety of motion furniture designs. With particular reference now to the drawings, the structural and functional aspects of the present invention are described with more particular detail. With reference now to FIGS. 1A through 1C, wall proximity reclining chair 20 includes a seat frame 22 having an arm rest or side frame 24, and further includes a reclinable seat back 26 and movable leg rest assembly 28. FIG. 1A illustrates wall proximity reclining chair 20 in its upright position, with leg rest assembly 28 retracted within the chair. FIG. 1B illustrates the wall proximity reclining chair 20 in its partially reclined or intermediate position, in which leg rest assembly 28 is fully extended and seat back 26 is partially reclined. Leg rest assembly 28 is positionable between a retracted position shown in FIG. 1A and an extended position as shown in FIGS. 1B and 1C. FIG. 1B further illustrates the wall proximity feature in that seat frame 22, side frame 24, and seat back 26 move forwardly along with leg rest assembly 28 when the wall proximity reclining chair 20 is moved from its upright position to its partially reclined position. Finally, FIG. 1C illustrates wall proximity reclining chair 20 in its fully reclined position. It should be noted that leg rest assembly 28 must be fully extended before seat back 26 can begin reclining. As will be appreciated from FIG. 1C, and the following detailed description, when wall proximity reclining chair 20 is in the partially reclined position, additional rearward pressure placed against seat back 26 by the occupant, correspondingly forces the seat frame 22, side frame 24 and leg rest assembly 28 forward. Accordingly, the all linkage mechanism is designed to allow seat back 26 to be placed within approximately 5-6 inches (12-15 cm) of a wall surface and achieve a fully reclined position without seat back 26 making contact with the proximal wall surface.
Referring now to FIGS. 2 through 7, the preferred embodiment of the present invention is illustrated in more detail. With particular reference to FIGS. 2 and 3, wall proximity reclining chair 20 includes right and left all linkage mechanisms 30, 32. FIG. 2 is an outside view of the right all linkage mechanism 30 in the upright position, and FIG. 3 is an inside view of the left all linkage mechanism 32 in the same position. After viewing FIGS. 2 through 7, it can be understood that the all linkage mechanisms 30, 32 are mirror images of each other. Each all linkage mechanism 30, 32 is pivotably secured to a longitudinal "L-shaped" base rail 34. Referring briefly to FIG. 8, the pair of longitudinal base rails 34 are then secured to front and rear "L-shaped" frame rails 36, 38. Each front and rear frame rail 36, 38 has a series of three hole formations 37 bored therein. The three holes 37 allow the spacing between two adjacent reclining chairs 20 to be selected for accommodating various styles of chairs which may have different thicknesses of padding and upholstery. The series of three hole formations 37 also allow a greater degree of precision and rigidity over a conventional slot and fastener.
With continued reference to FIG. 8, a pair of corner brackets 39 are secured between each longitudinal base rail 34 and the rear frame rail 38. The forward end of each corner bracket 39 is offset by 45.degree. so that it can be secured to the horizontal flange 58 of the longitudinal base rail 34 in two places with suitable fasteners. The opposite end of each corner bracket 39 is also secured to the rear frame rail 38 with suitable fasteners. In view of this interconnection scheme between the longitudinal base rails 34, the rear frame rail 38, and the corner brackets 39, one skilled in the art will readily appreciate the enhanced rigidity provided by securing corner brackets 39 with three fasteners as shown. Additionally, this interconnection scheme provides the precise alignment required by each all linkage mechanism 30, 32 with respect to the other. As disclosed, the front and rear frame rails 36, 38 can be sized to a variety of lengths such that wall proximity reclining chair 20 can embody a single reclining chair, or integrated within a love seat or sofa. Additionally, reclining chair 20 and the all-linkage mechanisms 30, 32 are suitable for use in a modular sofa assembly.
Referring now to FIGS. 2 through 8, the individual components forming each all linkage mechanism are described in more detail. Each all linkage mechanism 30, 32 is generally supported from its longitudinal base rail 34 by a four-bar linkage assembly 40. More specifically, the four-bar linkage assembly 40 includes a front support link 42 and a rear support link 44 which are pivotably coupled at their lower ends to the vertical flange 56 of the longitudinal base rail 34. The front support link 42 is connected to the base rail 34 at pivot 46 and the rear support link 44 is connected to the base rail 34 at pivot 48. Additionally, the front support link 42 is pivotably coupled to a secondary longitudinal link 60 at pivot 52 and the rear support link 44 is pivotably coupled to the secondary longitudinal link 60 at pivot 54 (FIG. 5). Secondary longitudinal link 60 includes two forward apertures 62, 64 for selectively adjusting the pivotal connection 52 with front support link 42. The right and left all-linkage mechanisms are interconnected to each other by a front cross member 152 which connects between the front support links 42, and a rear cross member 154 which connects between the rear support links 44.
The prominent link of each all linkage mechanism 30, 32 is the main longitudinal link 50 which supports the seat frame 22 and side frame or frames 24. Main longitudinal link 50 has its forward end directly supported at pivot 52 by the front support link 42, and has its rearward end indirectly supported by the recline linkage assembly 100. The main longitudinal link 50 further includes front and rear flanges 66, 68 which protrude outwardly from the main longitudinal link 50 for supporting and securing the seat frame 22 and side frame 24. The mid portion of the main longitudinal link 50 includes an attachment flange 70 for securing the cable 240 of the trip link assembly 234. An aperture 72 for journally supporting the square drive rod 80 is provided generally below this attachment flange 70. A bearing 74 is provided in aperture 72 for allowing the square drive rod 80 to easily rotate within aperture 72.
Referring briefly to FIGS. 8, 10 and 11, the adjustable seat slide 82 associated with each all-linkage mechanism 30, 32 is shown in more detail. More specifically, each main longitudinal link 50 is provided with an elongated aperture 76 for receiving a two piece nylon insert 78, thereby forming the lost motion slot 84 of the adjustable seat slide 82. Two metal friction washers 86 are provided on each side of the nylon insert 78. A threaded slide pin 88 having a head is extended through each friction washer 86 and thus through lost motion slot 84 for securing to other links of the mechanism. The threaded slide pin 88 also extends through the top pivot 52 of front support link 42, through the forward aperture 62 of the secondary connecting link 60, and finally through a washer 92. A tensioning spring 94 is retained on the inboard end of the threaded slide pin 88 by an adjustable fastener, such as a wing nut 96. Accordingly, the amount of compression between friction washers 86 and the nylon insert 78 of the seat slide assembly 82 can be adjusted by correspondingly adjusting the amount of tension provided by wing nut 96.
The adjustable seat slide 82 controls how easily the main longitudinal link 50 can move with respect to pivot 52 of front support link 42. Thus, the adjustable seat slide 82 controls the amount of friction placed on front pivot 52 during the reclining motion between the upright position and the intermediate position, and especially controls the amount of friction placed on nylon insert 78 as the main longitudinal link 50 moves between the intermediate and fully reclined positions. The adjustable seat slide 82 can be most easily accessed and adjusted from the front of reclining chair 20 when the leg rest assembly 28 is fully extended. The unique front access feature allows the seat slide 82 to be adjusted without moving the chair, or turning the chair over to access the mechanism. The advantage of a front access adjustment mechanism becomes even more significant when the wall proximity reclining chair 20 is incorporated into a love seat, sofa, or modular sofa, which could not be easily moved to access the adjustment feature. By rotating the wing nut 96 of each adjustable seat slide, the motion of each all linkage assembly 30, 32 can be adjusted for various sized seat occupants. Thus, the advantage of the adjustable seat slide 82 is that the reclining chair 20 can be adjusted for very smooth and consistent operation. Unlike other wall proximity relining chairs known to recline too quickly or too slowly, which produce an unnatural motion, the relining chair of the present invention can be adjusted to operate evenly throughout the recline phases.
Referring now to FIGS. 2 through 8, each all-linkage mechanism 30, 32 includes a recline linkage assembly 100 which is further defined by a first position recline linkage 102, and a second position recline linkage 104. With particular reference to FIGS. 3, 5 and 7, all inside views, the first position recline linkage 102 of the recline linkage assembly 100 is disclosed. More particularly, the first position recline linkage 102 includes a first connecting link 106 which is pivotally coupled at its top portion to the top of rear support link 44, and also connected to the rear portion of the secondary longitudinal link 60 at pivot 54. The bottom portion of first connecting link 106 is pivotally coupled to a base connecting link 108 at pivot 110. The opposite end of the base connecting link 108 is coupled to the vertical flange 56 of the longitudinal base rail 34 at pivot 112. Finally, a second connecting link 114 is also pivotally coupled to both the base connecting link 108 and the first connecting link 106 at pivot 110. The top portion of the second connecting link 114 is pivotally coupled to the rear portion of the main longitudinal link 50 at pivot 116. The second connecting link 114 further includes a curved offset top portion 118, and is preferably formed from heavy gauge steel. Thus, the first position recline linkage 102 is formed by the interconnection of first connecting link 106, base connecting link 108 and second connecting link 114.
The primary function of the first position recline linkage 102 is to control the forward motion of the four-bar linkage 40 supporting the main longitudinal link 50 as the chair 20 reclines away from the wall surface into the intermediate position. In operation, the first connecting link 106 allows the four bar linkage 40 to pivot forwardly while the base connecting link 108 rotates clockwise about pivot 112 until the base connecting link 108 engages the horizontal flange 58 of the longitudinal base rail 34 (FIGS. 3 and 5). Once the base connecting link 108 is prevented from further rotating, the four-bar linkage 40 is retained in a locked position and is prevented from pivoting and moving forward, thus forming an exceptionally stable base for supporting the seat occupant in the intermediate position. The second connecting link 114 then provides additional support to the rear portion of the main longitudinal link 50. As best viewed in FIG. 8, the second connecting links 114 of each recline linkage assembly 100 are interconnected by a cross member 156 having attachment flanges at each end. Cross member 156 is further reinforced by a central strengthening rib 158, which is preferably formed during the stamping process. The combination of the first connecting link 106, base connecting link 108 and second connecting link 114 form a tripartite linkage assembly 120, with the base connection link 108 disposed between the first connecting link 106 and the second connecting link 114. This interconnection forming tripartite linkage assembly 120 provides a connection which balances the forces placed upon each side of the base connecting link 108, thereby enhancing the operation of the all-linkage mechanisms 30, 32.
With reference now to FIGS. 2 and 7, the second position recline linkage 104 of the recline linkage assembly 100 is described in more detail. The primary function of the second position recline linkage 104 is to control the forward motion of the main longitudinal link 50 from the intermediate position to the fully reclined position, and to control the reclining motion of the seat back 26. The second position recline linkage 104 includes a seat back support link 122 having its forward end coupled to the main longitudinal link 50 at pivot 124. A recline connecting link 126 is pivotally coupled at its top portion to the seat back support link 122 at pivot 128. The lower and forward end of the recline connecting link 126 is pivotally coupled to the lower end of the vertical pivoting drive link 130 at pivot 132. The vertical pivoting drive link 130 is connected to the lower middle portion of the main longitudinal link 50 at pivot 134. The upper end of the vertical pivoting drive link 130 is pivotally connected to the forward end of a pivot control link 136 at pivot 138. The rear end of the pivot control link 136 is commonly connected to pivot 54 of the rear support link 44. A lost motion slot 140 is formed within the mid section of the pivot control link 136, which is retained against the secondary longitudinal link 60 by a stud 142 secured within the secondary longitudinal link 60. The combination of the lost motion slot 140 and the stud 142 allows for movement between these links, while also preventing deflection of the links during the reclining phases.
The upstanding portion 144 of the seat back supporting link 122 includes a rearward facing notch 146 for receiving the locking cam mechanism 148 of the seat back connecting bracket 150. The seat back connecting bracket 150 is secured to the upright side frame member of the detachable seat back 26 with suitable fasteners. A more detailed description of the components associated with the seat back connecting bracket 150 can be found in U.S. Pat. No. 5,184,871, entitled "Detachable Chair Back," which is expressly incorporated herein by reference, and which is commonly owned by the Assignee of the present invention.
With reference now to FIGS. 2, 3 and 8, the square drive rod 80 and its associated drive assemblies are described in more detail. As best seen in FIG. 8, square drive rod 80 is journally supported at each end by the main longitudinal links 50. A series of drive links are secured to the square drive rod 80 which perform various functions associated with the all linkage mechanisms 30, 32. As best viewed in FIG. 2, an outboard drive link 160 is rigidly secured at each end of square drive rod 80. The opposite end of the outboard drive link 160 is pivotally connected to the outboard pantograph connecting link 162 at pivot 164. The outboard drive link 160 and the outboard pantograph connecting link 162 serve to initiate the extension of leg rest assembly 28 via pantograph linkage assembly 260. The combination of these links also serve as an over-center mechanism to lock the leg rest assembly 28 in the retracted position. The universally shaped outboard drive link 160 can be used on both ends of the square drive rod 80, and includes a connecting flange 166 for engaging a flat surface of the square drive rod 80. The connecting flange 166 is preferably secured to the square drive rod 80 with a threaded fastener 168. The outboard drive link 160 further includes a recessed portion 170 for receiving a stopping stud 172 formed on the outboard pantograph connecting link 162. The stopping stud 172 prevents the over-retraction of the leg rest assembly 28 when the outboard drive link 160 is in the over-center position (FIGS. 2 and 12A).
The square drive rod 80 also includes an inboard drive link 180 which is journally supported on square drive rod 80. The inboard drive link 180 is supported by the square drive rod 80 near the inside face of the main longitudinal link 50 which serves to reduce the bowing forces placed on the square drive rod 80. The inboard drive link 180 includes a first drive arm 182 which is pivotally connected to the inboard pantograph connecting link 192 at pivot 184, and a second drive arm 186 which is pivotally connected to the control link 200 at pivot 188. In the preferred embodiment, pivot 184 is formed using a screw-in rivet 308 which facilitates easier manufacturing and service. The first drive arm 182 and the second drive arm 186 are preferably welded to a cylindrical connecting ferrule 190 having a circular inner portion which slips over the square drive rod 80. The connecting ferrule 190 maintains a rigid connection between the first drive arm 182 and the second drive arm 186. This rigid connection allows power to be transferred from control link 200 and second drive arm 186, through the first drive arm 182 and inboard pantograph connecting link 192, and to the pantograph linkage assembly 260 for fully extending the leg rest assembly 28. Connecting ferrule 190 is supported on square drive rod 80 by a pair of plastic bushings (not shown), preferably nylon. Accordingly, inboard drive link 180 is journally supported by, and can move independently of square drive rod 80.
Turning specifically to FIGS. 3, 5 and 7, the S-shaped control link 200 of each all linkage mechanism 30, 32 is connected between the second drive arm 186 of the inboard drive link 180 at upper pivot 188, and the vertical flange 56 of the longitudinal base rail 34 at lower forward pivot 204. As disclosed, pivot 204 of control link 200 is forward of pivot 46 of the front support link 42. The control link 200 cooperates with the inboard drive link 180, in accordance with the gravity driven and spring biased operation of this mechanism, to impart the primary rotational force on the inboard drive link 180 (about the square drive rod 80) for extending the leg rest assembly 28, and to control the reclining of the all-linkage mechanisms 30, 32 from the upright position to the intermediate or TV position. More specifically, as the all-linkage mechanisms 30, 32 move forwardly and away from the wall into the intermediate position, the pair of control links 200 (one for each all-linkage mechanism 30, 32) force the angular rotation of the inboard drive link 180. The connection of the first drive arm 182 of the inboard drive link 180 to the inboard pantograph connecting link 192 forces the extension of the leg rest assembly 28 via pantograph linkage assembly 260 as the mechanisms 30, 32 and chair 20 recline into the intermediate position.
However, the geometry of the interconnections between control link 200, and the inboard drive link 180 and base rail 34 contributes to the proper operation of the leg rest assembly 28. More specifically, as the all-linkage mechanisms 30, 32 move from the intermediate position to the fully reclined position, the leg rest assembly 28 must be maintained in the fully extended position. This in turn requires that the inboard drive link 180 and its first and second drive arms 182, 186 also maintain a constant position as the main longitudinal links 50 move forwardly into the fully reclined position. When comparing FIGS. 5 and 7, it can be seen that control link 200 rotates in a clockwise direction about pivot 204 as the main longitudinal link 50 moves forwardly and upwardly into the fully reclined position. While the purpose of control link 200 is to impart a rotational force on inboard drive link 180 for extending the leg rest assembly 28 during the first or intermediate recline phase, the control link 200 must keep the inboard drive link 180 stationary during the second or full recline phase as the control link 200 rotates about lower pivot 204. This is accomplished through the locations and geometries associated with the pivots 188 and 204 of the control link 200 in combination with the length of the second drive arm 186 and the curvilinear path defined by lost motion slot 84 and pivot 52 associated with the adjustable seat slide assembly 82. Accordingly, one skilled in the art will appreciate that as the lost motion slot 84 moves forwardly with respect to front pivot 52, control link 200 can rotate clockwise about pivot 204 without causing any further rotation of the inboard drive link 180 through second drive arm 186. Thus, the leg rest assembly 28 is maintained in the fully extended position as the all-linkage mechanisms 30, 32 move from the intermediate position to the fully reclined position.
Referring now to FIGS. 8 and 9, each all linkage mechanism 30, 32 further includes a spring assist drive linkage 210 interconnected between the square drive rod 80 and the front frame rail 36. The spring assist drive linkage 210 includes an over-center drive link 212 which is rigidly secured to the square drive rod 80 with an attachment flange 214. The attachment flange 214 is preferably secured to the square drive rod 80 with a threaded fastener 216. As disclosed, fastener 216 is a TORX.RTM. fastener. The opposite or rearward facing end of the over-center drive link 212 (when chair 20 is in the upright position, FIGS. 2 and 3) includes a pivot 218 for connecting to C-shaped over-center connecting link 220. An aperture 222 is formed in the opposite end of the C-shaped over-center connecting link 220 for retaining a biasing spring 224 which connects between the over-center connecting link 220 and one of the spring retaining tabs 99 formed in the horizontal flange 98 of the front frame rail 36. In operation, the spring assist drive linkage 210 imparts a biasing force on square drive rod 80 in either a clockwise or counterclockwise direction, depending on which side of the center line the C-shaped over-center connecting link 220 is located. The spring assist drive linkage 210 biases drive rod 80 in a first direction when the leg rest assembly 28 is extended, and biases drive rod 80 in a second, opposite direction when the leg rest assembly is retracted. Thus, the spring assist drive linkage 210 provides square drive rod 80 with a rotational mechanical advantage, while also providing a forward force which serves to pull each all-linkage mechanism 30, 32 with respect to the front frame rail 36, from the upright position to the intermediate and fully reclined positions.
The wall proximity reclining chair 20 is also provided with an adjustable drive spring assembly 310 which provides a forward bias to the four-bar linkage 40, and assists in the reclining of the chair 20. As best illustrated in FIG. 8, the adjustable drive spring 312 extends generally between the front frame rail 36 and the rear crossmember 154. A horizontal slot 314 formed in the rear crossmember 154 receives a spring adjustment bracket 316 having a series of holes 318, preferably seven, formed therein. The forward and lower end of the drive spring 312 is secured within one of the spring retaining tabs 99 formed in the horizontal flange 98 of the front frame rail 36. The opposite end of drive spring 312 is secured within an aperture 320 formed in the forward end of the spring adjustment bracket 316. A retaining pin 322 can be selectively placed within one of the series of holes 318. By changing the location of retaining pin 322 within the series of holes 318, the amount of tension on drive spring 312, and thus the amount forward force provided to the four-bar linkage 40 can be selectively adjusted.
With reference now to FIGS. 12A and 12B, the cable release assembly 230 which initiates the recline function from the upright position to the intermediate position is described in more detail. The cable release assembly 230 includes the cable release mechanism 232, mounted to the side frame 24 of the chair 20, and the trip link assembly 234, which is mounted to the main longitudinal link 50 at various points. While only one cable release assembly. 230 is required, the cable release assembly 230 can be mounted to either side of the wall proximity reclining chair 20. The cable release mechanism 232 includes a release handle 236 pivotally mounted to handle bracket 238. One end of the release cable 240 is secured to the release handle 236, and the other end of the release cable 240 is mounted to the trip link assembly 234. The outside sheathing 242 of the release cable 240 is secured between the handle bracket 238 at one end, and the cable mounting flange 70 of the main longitudinal link 50 at the opposite end. The end of the outside sheathing 242 which attaches to cable mounting flange 70 is provided with a slotted flag 258 that can be easily slipped over cable mounting flange 70. The aperture formed in slotted flag 258 fits snugly around mounting flange 70 and can be securely retained without a fastener. This feature allows for ease in manufacturing, and also facilitates in-field service because the slotted flag 258 can be easily slipped on and off mounting flange 70.
The trip link assembly 234 includes an L-shaped trip link 250 coupled to the main longitudinal link 50 at pivot 244. The L-shaped trip link 250 has an upper retaining pin 246 and a lower engaging pin 248 secured thereto. The details of trip link 250 are best illustrated in FIG. 12C. The upper retaining pin 246 includes a circular recess 252 for retaining the release cable 240 and a biasing spring 254. An eyelet 241, secured to the end of cable 240, slips over retaining pin 246, and past circular recess 252. The hook end of biasing spring 254 is placed into circular recess 252, which serves to secure spring 254 onto retaining pin 246, and also to lock the eyelet 241 onto retaining pin 246. The opposite end of the biasing spring 254 is secured within notch 256 formed on a rearward edge of the main longitudinal link 50. The biasing spring 254 retains the trip link 250 in its upper retracted position. The biasing spring 254 also helps to secure slotted flag 258 around cable mounting flange 70 because the release cable 240 is always under tension. The lower engaging pin 248 extends outwardly from the L-shaped trip link 250 for engaging the top edge or cam surface 174 of the outboard drive link 160. The geometry of cam surface 174 has been designed with a specific slope angle .THETA. to optimize the release action provided by the cable release assembly 230. As disclosed, the slope angle .THETA. provides additional mechanical advantage to trip link 250 for rotating outboard drive link 160. The slope angle .THETA. of cam surface 174 also enables lower engaging pin 248 to sufficiently rotate outboard drive link 160 for initiating extension of the leg rest assembly 28 by utilizing approximately one half of the stroke of release handle 236. Preferably, slope angle .THETA. is approximately 10 degrees. However, one skilled in the art will appreciate that variations in slope angle .THETA. are within the slope of the present invention.
When the wall proximity reclining chair 20 is in its upright position, the outboard drive link 160 is locked into its retracted and over-center position with respect to the square drive rod 80. In operation, the L-shaped trip link 250 serves to engage and rotate the outboard drive link 160 downwardly and forwardly, thus rotating the square drive rod 80 counterclockwise, as the release handle 236 is pulled outwardly from the chair side frame 24. The forward rotation of outboard drive link 160 and outboard pantograph connecting link 162 initiates the extension of the leg rest assembly 28 through the pantograph linkage assembly 260. As the L-shaped trip link 250 rotates the outboard drive link 160 counterclockwise, and thus over the center-line position, the gravity actuated feature of the wall proximity chair 20 drives the various reclining linkages into the intermediate reclined position.
Referring back to FIGS. 2 through 7, the leg rest assembly 28 of the wall proximity reclining chair 20 is disclosed in more detail. The leg rest assembly 28 includes a pantograph linkage assembly 260 having a foot rest linkage 262 and an ottoman linkage 290. The pantograph linkage assembly 260 is pivotally coupled to the main longitudinal link 50 via pantograph support link 264 at pivot 266, and pantograph drive link 268 at pivot 270. In the preferred embodiment, pivots 266 and 270 are formed using screw-in rivets 308 which secure the respective links. These screw-in rivets 308 serve a dual purpose. First, the screw-in rivets 308 make each all linkage mechanism 30, 32 easier to manufacture because the pantograph linkage assembly 260 can be secured to the main longitudinal link 50 after each sub-assembly is fabricated. This eliminates the need for specialized fixtures for supporting the entire mechanism during assembly at the riveting station. Second, the screw-in rivets 308 allow the pantograph linkage assembly 260 to be serviced in the field. If for some reason, the pantograph linkage assembly 260 becomes inoperable after the chair has been purchased, the screw-in rivets 308 allow for replacement in the field without sending the reclining chair 20 back to the factory.
With continued reference to FIGS. 2 through 7, a forward connecting link 272 is connected to the forward end of the pantograph support link 264 at pivot 274. The opposite end of the forward connecting link 272 is also connected to the foot rest support link 276 at pivot 278. A rearward connecting link 280 includes a first pivot 282 for connecting to the pantograph drive link 268, an intermediate pivot 284 for connecting to the pantograph support link 264, and a forward pivot 286 for connecting to the foot rest support link 276. A foot rest board 288 is supported at each end by the foot rest support links 276 of each foot rest linkage 262.
In the preferred embodiment, the leg rest assembly 28 includes an ottoman linkage assembly 290 which provides more continuous leg support to the seat occupant. The ottoman linkage 290 includes an ottoman support link 292 which connects to pivot 294 of the pantograph drive link 268. The opposite end of the ottoman support link 292 includes a flange 296 for supporting the mid-ottoman board 298. An ottoman control link 300 is connected between the main longitudinal link 50 at pivot 302 and a mid-portion of the ottoman support link 292 at pivot 304. As described above, pivot 302 is also preferably a screw-in rivet 308 for allowing easier manufacturing and replacement of the pantograph linkage assembly 260. The upholstered and cushioned mid-ottoman board 298 rests behind the foot rest board 288, when the chair 20 is in the upright position. As the all-linkage mechanisms 30, 32 move from the upright position into the intermediate position, the ottoman linkage 290 extends forwardly and upwardly, thereby moving the mid-ottoman board 298 between, and in line with the foot rest board 288 and the upholstered seat cushion, positioned on the seat frame 22. Accordingly, the upholstered seat cushion, mid-ottoman board 298 and leg rest board 288 provide a continuous line of leg support for enhancing the overall comfort of the reclining chair 20.
The outboard pantograph connecting link 162 and the inboard pantograph connecting link 192 both connect to the pantograph drive link 268 at common pivot 306. The opposite ends of the outboard and inboard pantograph connecting links 162, 192 are respectively coupled to their associated drive links 160, 180. As described above, the primary purpose of outboard drive link 160 and outboard connecting link 162 is to initiate the extension of the pantograph linkage assembly 260, and to initiate rotation of the inboard drive link 180 about square drive rod 80 via inboard pantograph connecting link 196. Once the inboard drive link 180 rotates to move the control link 200 past its over center position, the spring assist drive linkage 210 and the adjustable drive spring assembly 310 provide additional forward biasing or transporting the four-bar linkage 40 into the partially reclined position. As can be appreciated from the above description in view of the drawings, inboard drive link 180 and inboard pantograph connecting link 192 provide the primary mechanical force on pantograph drive link 268 for extending and retracting each pantograph linkage assembly. This design feature further enhances the operation of the gravity driven recline function of the present invention.
With continued reference to FIGS. 2 through 7, in view of FIGS. 1A through 1C, the functional operation of wall proximity reclining chair 20 is described in more particular detail. Each all linkage mechanism 30, 32 is maintained in its upright position by its spring assist drive linkage 210. More specifically, the biasing spring 224 which extends between the front frame rail 36 and C-shaped over center connecting link 220 forces square drive rod 80 into its retracted position through over-center drive link 212, thereby locking the reclining chair 20 in the upright position. As discussed above, the outboard drive link 160 is also held in an over-center condition. However, the outboard drive link 160 is prevented from over retracting the leg rest assembly 28 by stopping stud 172 of the outboard pantograph connecting link 162. Additionally, the control link 200 is also designed as a over-center mechanism which also serves to lock the reclining chair 20 in the upright position. Pressure from a seated occupant causes the control link 200 to impart a clockwise rotational force on inboard drive link 180, and thus serves to keep the leg rest assembly 28 retracted, and the chair 20 in the upright position.
Upon initiating the trip link assembly 234, the leg rest assembly 28 begins to extend, and the main longitudinal link 50 then begins moving forwardly via the front and rear support links 42, 44, which are pivotably coupled to the vertical flange 56 of the longitudinal base rail 34. As the main longitudinal link 50 moves forwardly into the partially reclined position, the rear portion of the main longitudinal link 50 moves forwardly and downwardly as the triangular linkage formed by the rear support link 44, first connecting link 106, base connecting link 108, and second connecting link 114, rotates downwardly about pivot 112 until the tripartite linkage assembly 120 contacts the horizontal flange 58 of the longitudinal base rail 34. The base connecting link 108 pivots forwardly and downwardly about its base rail pivot 112. Eventually, the tripartite linkage assembly 120, and especially the base connecting link 108, bottoms out against the longitudinal base rail 34. The mechanism is designed so that the leg rest assembly 28 is fully extended when the base connecting link 108 contacts the base rail 34. The forward and downward motion of the rear portion of the main longitudinal link 50 causes the seat back 26 to also move downwardly and to be tipped rearwardly through the seat back support link 122 and recline connecting link 126.
During this initial reclining motion, the control link 200 moves across its pivotable center line and into its primary range of operation. Furthermore, the control link 200 forces the extension of the pantograph linkage assembly 260 through the rotation of inboard drive link 180 about square drive rod 80 as the mechanism travels forwardly and downwardly in conjunction with the main longitudinal link 50. As discussed above, the first position recline linkage 102 is primarily responsible for controlling the motion of the main longitudinal link 50 as the all linkage mechanism 30, 32 travels from the upright position to the intermediate position. It should be noted that the second position reclining linkage 104 remains essentially stationary while the main longitudinal link 50 is transported from the upright position to the intermediate position. It should also be noted that the seat back 26 cannot be reclined until the leg rest assembly 28 is fully extended. Likewise, the seat back 26 must be in the upright position before the leg rest assembly 28 can be fully retracted.
The second recline phase is initiated by rearward and downward pressure on the seat back 26, which correspondingly pivots the seat back support link 122 downwardly about its front pivot 124 with the main longitudinal link 50. The recline connecting link 126 is then driven forwardly. The forward driving motion of the recline connecting link 126 causes the vertical pivoting drive link 130 to rotate in a counter clockwise direction about its middle pivot 134 with the lower portion of the main longitudinal link 50. Accordingly, the force provided by the seat occupant leaning back into seat back 26 provides the requisite leveraging force through second position recline linkage 104 to the recline connecting link 126 and the vertical pivoting drive link 130 to forwardly drive the main longitudinal link 50 with respect to the adjustable seat slide 82. The second position recline linkage 104 and the adjustable seat slide 82 further allow the seat occupant to achieve an infinite number of positions within the range of motion provided by lost motion slot 84.
The front and rear support links 42, 44 remain completely stationary while the main longitudinal link 50 is driven forwardly and upwardly via the front seat slide 82 and second position recline linkage 104 when the all linkage mechanism 30, 32 is fully reclined. Additionally, the first connecting link 106 and base connecting link 108 of the tripartite linkage assembly 120 also remain stationary during the second recline phase. However, the second connecting link 114 pivots about its lower pivotable connection in a forward and upward movement about this lower pivot 110 during the second recline phase. This motion correspondingly drives the rear portion of the main longitudinal link 50 in a forward and upward direction. Accordingly, the seat frame 22 and seat back 26 achieve a flatter reclined position.
The chair 20 is moved from the fully reclined position to the intermediate position by the seat occupant leaning forward so that the main longitudinal link 50 slides rearwardly about front seat slide 82 and second position recline linkage 104. Once in this position, the leg rest assembly 28 can be retracted by the seat occupant to move and lock the reclining mechanisms 30, 32 into the upright position. This is accomplished by the seat occupant placing downward and rearward pressure on the leg rest assembly 28, which causes the leg rest assembly 28 to retract and the chair 20 to move from the intermediate position to the upright position. When the leg rest assembly 28 is fully retracted, the outboard drive link 160 is moved into its over center position, thereby locking the all linkage mechanisms 30, 32 into the upright position. Extension of the leg rest assembly 28 can then be initiated by activating the trip link assembly 234.
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
  • 1. A reclining chair comprising:
  • a base;
  • a support linkage assembly pivotally supported from the base;
  • a longitudinal link operably interconnected to the support linkage assembly;
  • a recline linkage assembly operably coupled to the longitudinal link and to the base for controlling movement of the longitudinal link from an upright position to at least one reclined position;
  • a rotatable drive shaft journally supported by the longitudinal link; and
  • a pivot control assembly including a pivot drive link rotatably supported on the drive shaft and a pivot control link having a first end pivotally connected to the pivot drive link and a second end pivotally connected to the base;
  • a leg rest assembly supported from the longitudinal link and operably coupled to the drive shaft for movement from a retracted position to an extended position in response to rotation of the drive shaft in a first direction.
  • 2. The reclining chair of claim 1 further including a seat back and seat back support link for pivotally interconnecting the seat back to the longitudinal link for reclining between the upright position and the at least one reclined position.
  • 3. The reclining chair of claim 1 wherein the control link operates as an over-center mechanism.
  • 4. The reclining chair of claim 1 further including a spring assist drive linkage operably connected between the drive shaft and the base.
  • 5. The reclining chair of claim 4 wherein the spring assist drive linkage operates as an over-center mechanism.
  • 6. The reclining chair of claim 1 wherein the longitudinal link is operably coupled to the support linkage assembly through an adjustable sliding mechanism.
  • 7. The reclining chair of claim 6 wherein the adjustable sliding mechanism includes a lost motion slot formed in the longitudinal link, and adjustable compression means for selectively varying the amount of force placed on the lost motion slot.
  • 8. The reclining chair of claim 1 wherein the support linkage assembly includes front and rear support links pivotally coupled to a base link, and wherein the front and rear support links are pivotally interconnected with a secondary connecting link.
  • 9. The reclining chair of claim 1 wherein the recline linkage assembly further includes a first position recline linkage and a second position recline linkage.
  • 10. The reclining chair of claim 9 wherein the first position recline linkage controls reclining movement of the longitudinal link from the upright position to an intermediate position.
  • 11. The reclining chair of claim 10 wherein the second position recline linkage controls the reclining movement of the longitudinal link from the intermediate position to a fully reclined position.
  • 12. The reclining chair of claim 1 wherein the leg rest assembly further includes a pantograph linkage assembly having a foot rest linkage and an ottoman linkage.
  • 13. The reclining chair of claim 1 further including a trip link assembly for initiating movement of the reclining chair from the upright position to the at least one reclined position.
  • 14. The reclining chair of claim 1 wherein the base includes a front frame rail and a rear frame rail interconnected by a longitudinal base rail.
  • 15. The reclining chair of claim 14 wherein the base further includes at least one corner bracket secured between the longitudinal base rail and the rear frame rail.
  • 16. The reclining chair of claim 1 wherein an adjustable drive spring mechanism is operably connected between a forward portion of the base and a rear cross member.
  • 17. A reclining chair comprising:
  • a base;
  • a four-bar linkage assembly pivotally supported from the base;
  • a longitudinal link operably supported from the four-bar linkage assembly;
  • a recline linkage assembly operably coupled to the longitudinal link and to a base link of the four-bar linkage assembly for controlling movement of the longitudinal link from an upright position to at least one reclined position;
  • a rotatable drive shaft extending transversely to and rotatably supported by the longitudinal link;
  • a pivot control assembly including a pivot drive link journally supported on the drive shaft and a pivot control link having a first end pivotally connected to the pivot drive link and a second end pivotally connected to the base; and
  • a leg rest assembly supported from the longitudinal link and operably coupled to the drive shaft for movement from a retracted position to an extended position in response to rotation of the drive shaft in a first direction;
  • whereby the reclining chair may be placed adjacent a wall surface in an upright position and moved into the at least one reclined position without the reclining chair contacting the wall surface.
  • 18. A reclining chair comprising:
  • a base;
  • a support linkage assembly pivotally supported from the base;
  • a longitudinal link operably interconnected to the support linkage assembly;
  • a recline linkage assembly operably coupled to the longitudinal link and to the base for controlling movement of the longitudinal link from an upright position to at least one reclined position;
  • a rotatable drive shaft journally supported by the longitudinal link;
  • a control link operably coupled between a drive link rotatably supported on the drive shaft and the base for imparting a rotational force on the drive link as the longitudinal link moves between the upright position and the at least one reclined position;
  • a leg rest assembly supported from the longitudinal link and operably coupled to the drive shaft and the drive link for movement from a retracted position to an extended position in response to rotation of the drive shaft and the drive link in a first direction;
  • whereby the reclining chair may be placed adjacent a wall surface in an upright position and moved into the reclined position without the reclining chair contacting the wall surface.
  • 19. A reclining chair comprising:
  • a base;
  • a four-bar linkage assembly pivotally supported from the base, the four-bar linkage assembly having front and rear support links pivotally coupled to a base link, and wherein the front and rear support links are pivotally interconnected with a secondary connecting link;
  • a longitudinal link operably supported from the four-bar linkage assembly;
  • a recline linkage assembly operably coupled to the longitudinal link and to the base link of the four-bar linkage assembly for controlling movement of the longitudinal link from an upright position to at least one reclined position, the recline linkage assembly having a first position recline linkage and a second position recline linkage;
  • a rotatable drive shaft extending transversely to and journally supported by the longitudinal link;
  • a control link operably coupled between a drive link rotatably supported on the drive shaft and the base for imparting a rotational force on the drive link; and
  • a leg rest assembly supported from the longitudinal link and operably coupled to the drive shaft and the drive link for movement from a retracted position to an extended position in response to rotation of the drive shaft and the drive link in a first direction;
  • whereby the reclining chair may be placed adjacent a wall surface in an upright position and moved into the reclined position without the reclining chair contacting the wall surface.
  • 20. The reclining chair of claim 19 wherein the longitudinal link is operably coupled to the four-bar linkage assembly through an adjustable sliding mechanism.
  • 21. The reclining chair of claim 20 wherein the adjustable sliding mechanism includes a lost motion slot formed in the longitudinal link, and adjustable compression means for selectively varying the amount of force placed on the lost motion slot.
  • 22. The reclining chair of claim 19 further including a seat back and seat back support link for pivotally interconnecting the seat back to the longitudinal link for reclining between the upright position and the reclined position.
  • 23. The reclining chair of claim 19 further including a trip link assembly for initiating movement of the reclining chair from the upright position to at least one of the reclined positions.
  • 24. The reclining chair of claim 19 wherein the control link operates as an over-center mechanism.
  • 25. The reclining chair of claim 19 further including a spring assist drive linkage operably connected between the drive shaft and the base.
  • 26. The reclining chair of claim 25 wherein the spring assist drive linkage operates as an over-center mechanism.
  • 27. The reclining chair of claim 19 wherein the first position recline linkage controls reclining movement of the longitudinal link from the upright position to an intermediate position.
  • 28. The reclining chair of claim 27 wherein the second position recline linkage controls the reclining movement of the longitudinal link from the intermediate position to a fully reclined position.
  • 29. The reclining chair of claim 19 wherein an adjustable drive spring mechanism is operably connected between a forward portion of the base and a rear cross member.
  • 30. The reclining chair of claim 19 wherein the base includes a front frame rail and a rear frame rail interconnected with the base link.
  • 31. The reclining chair of claim 30 wherein the base further includes at least one corner bracket secured between the base link and the rear frame rail.
  • 32. A method for moving a reclining mechanism from an upright position to a reclined position comprising the steps of:
  • providing a base;
  • providing a support linkage assembly pivotally supported from the base;
  • providing a longitudinal link operably supported from the support linkage assembly;
  • providing a recline linkage assembly operably coupled to the longitudinal link and to the support linkage assembly, said recline linkage assembly including a first position recline linkage and a second position recline linkage;
  • transporting the reclining mechanism from an upright position to an intermediate reclined position until a portion of the first recline linkage contacts the base;
  • retaining the support linkage assembly in a fixed position when the reclining mechanism is in the intermediate reclined position; and
  • transporting the reclining mechanism from the intermediate reclined position to a fully reclined position until the rear portion of the seat slide contacts a stopping pivot.
  • 33. The method of claim 32 further comprising the step of providing a rotatable drive shaft extending transversely to and journally supported by the longitudinal link.
  • 34. The method of claim 33 further comprising the step of providing a control link operably coupled between a drive link, rotatably supported on the drive shaft, and the support linkage assembly for imparting a rotational force on the drive link.
  • 35. The method of claim 33 further comprising the step of providing a spring assist drive linkage for imparting a rotational force on the drive shaft.
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