BACKGROUND OF THE INVENTION
Seats for motor vehicles and the like may include one or more adjustment features such as a seat back tilt mechanism that selectively retains the seat back in a position selected by a user. The seat may include additional adjustment features such as fore-aft sliding of the seat relative to the vehicle floor, and other such adjustment features. Various types of mechanisms have been developed to retain the seat components in a desired position. Such mechanisms may be actuated by a cable that is connected to a manually-operated release mechanism by an elongated cable. Also, elongated cables may be utilized to operably interconnect a lever or other release member located inside a vehicle to a component such as a hood release latch. Various mechanisms for manual user input have been developed. However, known mechanisms may suffer from various drawbacks.
BRIEF SUMMARY OF THE INVENTION
One aspect of the present invention is a release mechanism of the type utilized to shift an elongated connector to selectively release an adjustment mechanism. The release mechanism includes a housing defining a pivot element, and a rotor disposed within the housing and pivotably engaging the pivot element for rotation about an axis. The rotor is adapted to be manually rotated by a user, and the rotor includes a connecting feature that provides for connecting an end of an elongated flexible cable to the rotor, such that rotation of the rotor shifts the elongated flexible cable. The release mechanism also includes a helical coil spring having a first end connected to the housing, and a second end connected to the rotor. The coil spring is rotationally deformed to rotationally bias the rotor for rotation in a first direction about the axis, and the coil spring is also compressed, and biases the rotor axially away from the housing along the axis.
The housing may include a separate cover that snaps onto a main portion of the housing during assembly. The housing and rotor can be utilized in either a “left hand” or “right hand” orientation. The housing and rotor may be symmetrical about a center plane, and the direction of the rotational bias of the rotor can be changed by selecting a helical coil that generates either a clockwise or counter clockwise torque on the rotor. Also, the housing may include connecting features whereby a cable can be interconnected to the housing of the release mechanism at either of two opposite side faces of the housing.
The release mechanism may include a rotation-limiting feature such as a boss on the rotor and corresponding arcuate slot on the housing to limit rotation of the rotor relative to the housing. During assembly, the rotor is rotated against the spring bias relative to the main portion of the housing, and the rotor is shifted axially to move the boss into the arcuate slot. Friction between the boss and a side surface of the arcuate slot prevents shifting of the rotor that could otherwise occur due to the axial bias of the helical coil spring.
These and other features, advantages, and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims, and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially fragmentary side elevational view of a motor vehicle seat or the like including an adjustment mechanism and a release mechanism that is interconnected to the adjustment mechanism by an elongated cable;
FIG. 2 is a top plan view of a release mechanism according to one aspect of the present invention;
FIG. 3 is a front elevational view of the release mechanism of FIG. 2;
FIG. 4 is an exploded isometric view of the release mechanism of FIG. 2;
FIG. 4A is an exploded isometric view of the release mechanism of FIG. 2 showing the spring in an uncompressed state;
FIG. 5 is a partially exploded isometric view of the release mechanism of FIG. 2;
FIG. 6 is a partially fragmentary enlarged, isometric view of a portion of a release mechanism according to one aspect of the present invention;
FIG. 7 is a partially fragmentary, enlarged isometric view of a portion of a rotor of a release mechanism according to one aspect of the present invention;
FIG. 8 shows a coil spring according to one aspect of the present invention in an uncompressed state;
FIG. 9 shows the spring of FIG. 8;
FIG. 10 is an end view of the spring of FIG. 8; and
FIG. 11 is an enlarged, fragmentary view of a portion of the spring of FIG. 10.
DETAILED DESCRIPTION OF EMBODIMENTS
For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in FIG. 1. However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.
With reference to FIG. 1, a seat assembly 1 includes a seat portion 2 and a back portion 3 that is pivotally interconnected to the seat portion for fore-aft tilting movement as indicated by the arrow “A.” A releasable adjustment mechanism 4 selectively retains the back portion 3 at various positions B, B1, B2 etc. An adjustment mechanism 4 may be positioned on both the left and right sides of the seat 1. A support structure 5 interconnects the seat assembly 1 with a vehicle floor 6. The support structure 5 may include slides or the like (not shown) that permit movement of the seat assembly 1 in a fore-aft direction relative to the floor 6 of a vehicle as indicated by the arrow “C.” The seat portion 2, back portion 3, adjustment mechanism 4, and support structure 5 may comprise conventional, known components such that these parts will not be described in detail herein.
A release mechanism 10 is operably interconnected to the adjustment mechanism 4 by an elongated cable 11. The release mechanism 10 includes a movable input member such as a handle 12 that is movable as indicated by the arrow “R” by a user to selectively release adjustment mechanism 4 to permit tilting of the seat back 3.
With further reference to FIGS. 2-4 and 4A, mechanism 10 includes a housing 13 having a first portion 14 and a retainer or second portion (component) or cover 16 that together form an interior space 18. When assembled, a rotor 20 is rotatably interconnected with a pivot element such as boss or protrusion 22 of the first portion 14 for rotation about an axis “A1” (FIG. 4). As discussed in more detail below, a spring 25 includes a first end 26 that is interconnected to the first portion 14, and a second end 28 that is interconnected with rotor 20 to rotationally bias the rotor 20 relative to the first portion 14 for rotation about an axis “A1.” Rotor 20 includes an arm 34 having an end portion 36 that includes first and second connecting features 30A and 30B (cavities) that interconnect with a fitting 32 of cable 11 whereby rotation of rotor 20 longitudinally shifts the cable 11 and releases adjustment mechanism 4. The arm 34 is substantially symmetrical such that either connecting feature 30A or connecting feature 30B can be utilized to connect with a cable end fitting 32. In the illustrated example, the end fitting 32 is received in connector 30A to thereby pull on cable 11 upon rotation of rotor 20 in the direction of the arrow “R1.” An end portion 11A of cable 11 wraps around curved end surface 37 of arm 34. End surface 37 may include a relatively flat central portion 37A having a reduced radius about axis A1 to provide increased force on cable 11 as it wraps around central portion 37A. Cable end fitting 32 may be received in connecting feature 30B such that rotation of rotor 20 in a direction opposite the arrow “R1” pulls on cable 11 to actuate adjustment mechanism 4. The direction of rotational bias provided by spring 25 may be reversed if connecting feature 30B is utilized to thereby provide the proper rotational bias for a particular application. A bushing or fitting 38 includes an annular groove 39 that engages a selected one of the openings 40A-40D of sidewall 41A or 41B of the first portion 14 to slidably support cable 11 where it enters the first portion 14.
Rotor 20 includes a generally cylindrical extension 42 having a plurality of teeth or splines 44 that engage corresponding teeth or splines 46 on an interior portion of extension 47 of handle 12 in a known manner to interconnect rotor 20 and handle 12. A pair of transverse slots 48 receive a clip or other retainer (not shown) to retain handle 12 to rotor 20 in a conventional manner.
The first portion 14 includes a plurality of wedges 52 that protrude from sidewalls 41C, 41D, and 41E. Wedges 52 are received in openings 53 formed in transverse flaps or extensions 54 (see also FIGS. 2 and 3). The wedges 52 and corresponding connectors 53-54 retain cover 16 on the first portion 14 prior to installation of the release mechanism 10 on a seat assembly 1. Threaded fasteners 56 (FIG. 3) are received in openings 57 in the first portion 14 and cover 16 (FIGS. 2 and 3) and engage threaded openings in the seat structure to secure the release mechanism 10 to the seat assembly 1. Fasteners 56 also ensure that the first portion 14 and cover 16 remain assembled together when mechanism 10 is attached to the seat assembly 1.
With further reference to FIG. 5, arm 34 of rotor 20 includes cylindrical extension 64. The first portion 14 includes a ridge or sidewall 60 that protrudes from inner surface 58 of sidewall 59 of the first portion 14. When assembled, extension 64 is received in arcuate slot 62, and spring 25 rotatably biases extension 64 towards end surface 66 or end surface 68 of arcuate slot 62. Spring 25 may be configured to rotatably bias rotor 20 in a first direction R1, or a second direction that is opposite R1, depending upon which direction handle 12 is required to rotate when release mechanism 10 is installed on a seat or other structure. For example, in FIG. 1 mechanism 10 is mounted on a left side of a seat 2, and handle 12 rotates upwardly when the handle 12 is pulled by a user. However, mechanism 10 may also be installed on a seat at a lower right side edge whereby the mechanism 10 is rotated 180 degrees about a horizontal axis relative to the orientation shown in FIG. 1. If mechanism 10 is configured for use on a right side edge of a seat, the spring 25 is configured to provide a bias in the opposite rotational direction, and cable 11 will be configured to extend out of an opposite sidewall of the first portion 14. Because the mechanism 10 is substantially symmetrical (other than spring 25) about a center plane “P” (FIG. 2) cable 11 is oriented in either the configuration shown in FIG. 2 in solid lines, or in the configuration shown in dashed lines 11A as also shown in FIG. 2.
With further reference to FIG. 6, the first portion 14 includes an annular wall 70 protruding from inner side surface 58 of sidewall 59 of the first portion 14. An inner side of sidewall 70 includes a plurality of raised portions or pads 72 having cylindrical end surface portions 73. A ring-like annular space 76 is formed between boss 22 and cylindrical sidewall 70. A plurality of protrusions 74 project into annular space 76 from sidewall 59. A plurality of grooves 77 are formed between protrusions 74. Grooves 77 extend radially away from boss 22. When assembled, end 26 (see also FIG. 5) of spring 25 is received in a selected one of the grooves 77 to thereby rotationally retain the spring 25 relative to the first portion 14.
The protrusions 74 also define convex cylindrical outer surfaces 78 that face the concave cylindrical surfaces 73 of pads 72 of cylindrical sidewall 70. When assembled, the space between surfaces 73 and 78 receives end portion 80 (FIG. 7) of rotor 20. End portion 80 of rotor 20 includes a cylindrical inner side surface 81 that defines a cylindrical cavity or space 83. End portion 80 also includes a cylindrical outer surface 82. When mechanism 10 is assembled, end 28 (see also FIG. 4) of spring 25 is received in a selected one of a plurality of openings 85 in inner base surface 84 of cavity 83. An opening 86 in rotor 20 has a hexagonal shape to receive a hexagonal tool (not shown) during assembly of rotor 20 and the first portion 14 to control the rotational position of rotor 20 relative to the first portion 14.
During assembly, end 26 of spring 25 (FIGS. 4 and 4A) is positioned in a selected slot 77 (FIG. 6) of the first portion 14, with a portion of spring 25 being disposed between cylindrical sidewall 70 and boss 22 of the first portion 14. Spring 25 is initially in an uncompressed or “free” state wherein the individual coils of spring 25 are spaced apart as shown in FIGS. 4A, 8 and 9. Rotor 20 is then moved to a position adjacent the first portion 14, such that end 28 of spring 25 is received in a selected one of the openings 85 of rotor 20. Rotor 20 is then rotated relative to the first portion 14 using a hexagonal tool (not shown), such that spring 25 generates a torsional bias or force between the first portion 14 and rotor 20. Rotor 20 is then shifted axially along axis A1 (FIG. 4) to position end portion 80 of rotor 20 on the boss 22 of the first portion 14. End portion 80 of rotor 20 is received in the space 76 (FIG. 6) between surfaces 73 of pads 72 and the end surfaces 78 of protrusions 74. As the rotor 20 is moved into position relative to the first portion 14, protrusion 64 (FIG. 5) of rotor 20 is positioned in arcuate slot 62 of the first portion 14. After the extension 64 is positioned in arcuate slot 62, the torsional force acting on rotor 20 by the hexagonal tool is removed, and the torsional force caused by spring 25 causes extension 64 on arm 34 of rotor 20 to move into engagement with end 66 (or end 68) of arcuate slot 62. As rotor 20 is moved into position relative to the first portion 14, spring 25 is compressed in addition to being rotationally deformed. This causes spring 25 to generate an axial force tending to push rotor 20 away from the first portion 14. However, friction between extension 64 and end 66 (or 68) of arcuate slot 62 is sufficient to prevent the axial bias from shifting rotor 20 relative to the first portion 14. When compressed, the coils of spring 25 are in contact with one another or directly adjacent one another as shown in FIG. 4.
After the temporary subassembly of the first portion 14 and rotor 20 is formed, bushings 38 are assembled with the first portion 14, and end fitting 32 of cable 11 is positioned in connector 30A or connector 30B of arm 34 of rotor 20. It will be understood that these operations may be performed either before rotor 20 is installed in the first portion 14, or after rotor 20 is installed in the first portion 14. Cover 16 is then snapped onto the first portion 14 and retained thereon by wedges 52 and openings 53.
Referring back to FIG. 4, After the cover 16 and the first portion 14 are assembled, spring 25 shifts rotor 20 towards cover 16 slightly, such that annular bearing surface 90 of extension 42 of rotor 20 slidably engages an annular bearing surface 88 formed around opening 89 of cover 16 to prevent axial shifting of the rotor 20 away from the first portion 14 beyond a predefined position relative to the first portion 14. The engagement of bearing surfaces 88 and 90 prevents rattling of rotor 20 when installed to a seat, yet permits some variation in the sizing of the components.
When assembled, outer surface 82 (FIG. 4) of end 80 of rotor 20 slidably engages surface 73 (FIG. 6) of the first portion 14, and outer surface 92 of extension 42 of rotor 20 slidably engages surfaces or pads 94 (FIG. 4) of opening 89 in cover 16.
During assembly, handle 12 is positioned on extension 42 of rotor 20, and a clip or other retainer (not shown) is positioned in engagement with transverse slots 48 of extension 42 to thereby retain the handle 12.
Because the rotor 20 can be temporarily assembled with the first portion 14, rotor 20 does not need to be retained in position relative to the first portion 14 by a fixture or the like while cover 16 is installed. Thus, assembly of release mechanism 10 is simplified. Also, as discussed above, the axial bias of spring 25 ensures that the bearing surface 90 of rotor 20 remains in sliding engagement with the corresponding bearing surface 88 of cover 16. The bearing surfaces 88 and 90 may comprise low friction materials, such that very little frictional resistance is generated. This permits spring 25 to have a relatively low torsional stiffness to return handle 12 to the rest position.
With further reference to FIGS. 8-11, spring 25 may comprise a helical coil spring having a wire diameter of 1.14 mm with 10 coils. The coils may have a right hand or left hand wind direction as required to provide a right or left hand version of mechanism 10. The spring 25 has a free or unstressed length “L1” of 28.5 mm. In general, the length L1 may be about 23.0 mm to about 33.0 mm. However, lengths L1 outside this range may also be utilized if required for a particular application. During assembly, an axial force “F” is applied to the spring 25 as described in more detail above. This results in a compression of spring 25 to an installed length “L2” of 14.65 mm. Thus, the deflection of spring 25 when installed is about 13.85 mm.
The overall length “L3” of spring 25 in an unstressed or free state is 34.34 mm as shown in FIG. 8. The inner radius “R” is 1.40 mm, and the outer diameter “θ2” (FIG. 10) is 11.15 mm. The spring 25 may include straight portions 26A and 28A directly adjacent the ends 26 and 28, respectively. The inner dimension “D1” (FIG. 10) is 8.72 mm, and the outside diameter “D2” is 11.15 mm. With reference to FIG. 11, the angle “02” is 142.4°. Ends 26 and 28 extend at an angle “θ1” of 90°. Spring 25 is preferably made of spring steel or other suitable material such as music wire (ASTM A228), and the spring 25 has a maximum solid height of 12.65 mm. The specific dimensions given above are an example of one possible configuration for spring 25. However, the specific dimensions, shapes, materials, and other characteristics of spring 25 may vary as required for a particular application. For example, mechanism 10 may be utilized in connection with different types of seats requiring different force characteristics to release adjustment mechanism 4 (FIG. 1) or other such mechanism. It will be understood that the specific dimensions of the mechanism and spring 25 may vary as required, and the release mechanism 10 of the present application is not limited to any specific application.
As discussed above, the installed length L2 of spring 25 is greater than the solid height or length of spring 25. Accordingly, when spring 25 is installed in mechanism 10 spring 25 is in a compressed state. When spring 25 is in the compressed (installed) state, the spacing between the individual coils of spring 25 is reduced, and spring 25 generates a biasing force tending to expand the length of spring 25. As discussed above, this biasing force insures that bearing surface 90 of rotor 20 remains in sliding engagement with corresponding bearing surface 88 of cover 16.
As also discussed above, mechanism 10 may be assembled by temporarily assembling rotor 20 with the first portion 14, with friction between extensions 64 and end 66 (or end 68) of arcuate slot 62 to generate friction sufficient to prevent axial bias of spring 25 from shifting rotor 20 relative to the first portion 14. Alternatively, mechanism 10 may also be assembled as follows. First, the first portion 14 may be positioned in a fixture (not shown) or otherwise retained in a generally horizontal orientation with interior space 18 (FIG. 4) facing upwardly. Spring 25 is then positioned over boss 22, and shifted (if required) to cause end 26 of spring 25 to engage one of the grooves 77 (FIG. 6) of the first portion 14. The rotor 20 is then positioned on spring 25 such that spring 25 is received within cylindrical cavity or space 83 of rotor 20 (FIGS. 5 and 7), and end 28 of spring 25 is engaged with one of the openings 85 (FIG. 7) of rotor 20. The arm 34 of rotor 20 is initially oriented as shown in solid lines in FIG. 4A. This initial position is rotated 180° relative to the assembled orientation of arm 34 shown in dashed lines in FIG. 4A. The assembled orientation of arm 34 is also shown in solid lines in FIG. 4. After placing the rotor 20 onto the spring 25, cover 16 is positioned on rotor 20 with extension 42 of rotor 20 extending through opening 89 of cover 16. A hex tool (not shown) is positioned in hex opening 86 (FIG. 7) of rotor 20, and the rotor 20 is then rotated 180° until it is in the assembled rotational orientation (FIG. 4). Rotor 20 may be rotationally constrained due to engagement of extension 64 on arm 34 of rotor 20 with end 66 or 68 of arcuate slot 62. Alternatively, rotor 20 may be configured to temporarily engage cover 16 to prevent rotation of rotor 20 during the assembly process. After the cover 16 is positioned over rotor 20 and rotor 20 is rotated to its assembled angular orientation, the first portion 14 and cover 16 are pushed together and interconnected utilizing wedges 52 and openings 53 as described in more detail above.
Due to the axial compression (deflection), spring 25 generates about 24 N of axial force when assembled. This axial force biases rotor 20 away from the first portion 14, and into engagement with cover 16. Also, when assembled the rotational deflection or deformation of spring 25 causes the spring 25 to be preloaded such that it generates a torsional force of about 250 N-mm. Thus, when assembled spring 25 simultaneously generates a substantial axial biasing force and a substantial torsional biasing force.
The axial force/bias acting on rotor 20 ensures that the rotor does not rattle, and substantially eliminates noises from vibrations or the like. Furthermore, spring 25 has a longer length than conventional torsion springs utilized in prior mechanisms. The longer length allows spring 25 to have a lower torsional spring constant, thereby reducing the spring biasing force acting on the handle 12 (FIG. 1) for a given spring displacement. The total force required by a user in moving (rotating) handle 12 includes force required to overcome the torsion of spring 25 and the force required to actuate adjustment mechanism 4. Thus, reducing the torsional force generated by spring 25 reduces the total force a user must apply to handle 12 to actuate adjustment mechanism 4.
It is to be understood that variations and modifications can be made on the aforementioned structure without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.
Patent Grant
11052792
