Abstract:
A seat frame for reclining type seat which includes a toggle actuated release mechanism for the back support pivot joint. The release mechanism includes a toggle arm connected to peripheral lock members which mesh with rotatable gears connected to the back support. A manually operable lever arm is connected to the toggle arm knee joint to selectively shift the toggle arm between a normally locked position and an unlocked position wherein the back support may be shifted.

Description:
This is a continuation of copending application Ser. No. 07/390,081 filed on Aug. 7, 1989, now abandoned. 
    
    
     SUMMARY OF THE INVENTION 
     This invention relates to seat frames, and will have special application to seat frames with a shiftable back support, commonly referred to as a recliner. 
     Recliner seats, particularly those found in the vast majority of motor vehicles, normally include a manually operated, side located catch which releases a lock to allow the seat back to be shift between upright and reclined positions. 
     The recliner seat of this invention includes a toggle arm connected to one or two side located lock plates whose teeth mesh with the gears connected to the reclinable back support. A lever arm is connected to the knee joint of the toggle arm and is accessible through a slide actuator. The toggle arm may include a biasing spring to urge the lock plates into a locked position when the slide actuator is released. 
     Accordingly, it is an object of this invention to provide for an improved locking system for recliner seats. 
     Another object is to provide for a recliner seat locking system which utilizes a toggle type actuator. 
     Another object is to provide for a recliner seat locking system which is durable, efficient and economical. 
     Still another object is to provide for a recliner seat locking system which is more easily accessible to the user. 
     Other objects will become apparent upon a reading of the following description. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a reclining seat with the seat back in an upright position. 
     FIG. 2 is a perspective view of the seat frame and back frame with the back frame in an upright position. 
     FIG. 3 is a perspective view of the seat frame illustrating the locking system and actuator in a locked position. 
     FIG. 4 is a top plan view of the seat frame. 
     FIG. 5 is a sectional view taken along line 5--5 of FIG. 4. 
     FIG. 6 is a fragmented detail top plan view of the seat frame illustrating the right half of the toggle arm and lock plate in a locked position. 
     FIG. 7 is a fragmented detail top plan view similar to FIG. 6, but with the toggle arm and lock plate in an unlocked position. 
     FIG. 8 is a fragmented perspective view of an alternative seat support configuration. 
     FIG. 9 is a perspective view of the seat with the seat back in a reclined position. 
     FIG. 10 is a perspective view of the seat frame with the lock in an unlocked position. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The preferred embodiments herein described are not intended to be exhaustive or to limit the invention to the precise forms disclosed. They are chosen and described to explain the principles of the invention and its application and practical use so that other skilled in the art might utilize its teachings. 
     Referring first to FIGS. 1 and 9, reference numeral 10 refers generally to the recliner seat of this invention. Seat 10 includes a seat support 12, a back 14, and arm rests 16. Back support 14 is pivotally connected to seat support 12 so as to be shiftable between an upright seating position (FIG. 1) and a reclined position (FIG. 9). Arm rests 16 are optional and may be pivotally attached to the back support frame 20 as shown in FIG. 2. 
     Seat support 12 includes a seat frame 18 carried inside seat cushion 19 which is formed of covered foam. Back support 14 includes back frame 20 carried inside back cushion 17 also formed of covered foam. Arm rests 16 may also be carried inside foam cushions 15 to provide for maximum comfort of the user. 
     As shown in FIGS. 2-4, seat support frame 18 is generally rectangular and includes front frame member 22, side frame members 24, 26 and rear frame member 28. Although frame members 22, 24 and 26 are shown as a one-piece generally C-shaped channel part any acceptable construction is possible for use in this invention. In the construction shown, rear frame member 28 is connected between side frame members 24, 26 in a common manner. Mounting bars 30, 32 are connected between front frame member 22 and rear frame member 28 as shown. A plate 34 which defines slot 36 is connected across mounting bars 30, 32 as by welding or other conventional means. 
     Back support frame 20 includes a tubular frame member 38 defined by side frame members 40, 42 and upper frame member 46. As with seat support frame 18, frame members 40, 42 and 46 may be of one-piece construction or may be formed from multiple pieces connected in a common manner. Cross members 48 which are connected between frame members 40, 42 provide greater support and stability for back cushion 17. 
     Gear assemblies 50, 51 are positioned adjacent the rear portion of each seat support side frame member 24, 26. Each gear assembly 50, 51 includes an upright post part 52, 53 through which the gear assemblies are connected to tubular back support frame members 40, 42. A shaft 54 extends transversely through each gear assembly 50, 51 and is keyed thereto by conventional means such as pin 56 which allows for correlative rotation of the shaft and gear assemblies. Shaft 54 is journalled in supports 58 attached to seat side frame members 24, 26 as shown. A tension spring 60 is coiled about shaft 54 and has a first end connected to back support frame member 42 and a second end connected to seat support rear frame member 28 to control the speed at which back support 14 may recline and to bias the back support in a normally upright position. 
     The lock mechanism shown in the drawings includes one or more lock plates (two shown) 62, 63 connected at one end to frame members 24, 26 respectively as by fasteners 64. Each lock plate is preferably formed of bendable sheet metal and includes teeth 66, 67 which mesh with the teeth 55, 57 of gear assemblies 50, 51 when in the locked position of FIGS. 2-6. Each lock plate 62, 63 includes an integral tab outturned 68, 69 adjacent teeth 66, 67 and may include a central portion of narrowed dimensions to facilitate bending of the lock plate between the locked and unlocked positions. 
     A toggle arm 70 includes arm members 72, 74 which are connected to lock plates 62, 63 via fasteners 76 extending through the arm member and through lock plate tabs 68, 69. A lever arm 78 is connected to the connecting knee joint 80 of toggle arm members 72, 74 through pivot pin 82. Pivot pin 82 extends through plate slot 36 and is slidably held in the slot by a stop shown in the drawings (FIG. 5) as a conventional threaded nut 84 which is threaded onto pivot pin 82. Lever arm 78 is connected to slide actuator 86 by pivot pin 88 with the slide actuator extending outwardly of seat frame 18 through a slot 90 in frame member 24 to permit access by the seat user. A biasing member such as helical spring 91 is connected between toggle arm 70 and seat frame 18 to urge the toggle arm rearwardly to shift the lock plates 62, 63 into the locked position when actuator 86 is released. 
     FIG. 8 illustrates an alternative construction of plate 34 and depicts a subframe 92 which includes integral raised part 94 which has a guide slot 96. In this embodiment, back frame member 28 is formed integrally with subframe 92. All other parts of seat 10 function as shown in FIGS. 1-7, with the pivot pin 82 held in slot 96 in the same fashion as described above. 
     Seat back support 14 may be adjusted between the upright position of FIG. 1 and the reclined position of FIG. 9 as follows. With the back support 14 in the position of FIG. 1, a user slides actuator 86 forwardly in slot 90. Lever arm 78 slides forward to apply a pulling force on toggle arm knee joint 80. Toggle arms 72, 74 shift forwardly and apply a pulling force on lock plates 62, 63 through their connection to tabs 68, 69. The resiliency of lock plates 62, 63 causes the lock plates to bend towards each other as shown in FIGS. 7 and 10 to disengage teeth 66, 67 from gear teeth 55, 57. Back support 14 is now free to recline into the desired position. Due to the plurality of teeth in the gears and lock plates a multiplicity of positions may be selected for maximum flexibility and comfort of the user. When the desired position is selected, the user releases slide actuator 86. Spring 91 then urges the toggle arms 72, 74 rearward, and the lock plates return to their locked position automatically. Plate slot 36 (or slot 96 in FIG. 8) provides for straight line movement of lever arm 78 which insures that equal pulling force will be applied to lock plates 62, 63 for reliable locking and unlocking thereof. 
     It is to be understood that the invention is not limited to the detail above-given, but may be modified within the scope of the following claims.