VEHICLE HINGE ASSEMBLY WITH TUNABLE SPRING ASSEMBLY

RELATED APPLICATIONS

This application claims the benefit under 35 USC 1 19(e) to the applicant ^' s earlier filed United States Provisional Application Serial No. 60/875,815 filed 20 December 2006; and United States Provisional Application Serial No. 60/881 ,135 filed 19 January 2007.

SCOPE OF THE INVENTION

The present invention relates to a hinge assembly suitable for use with a variety of different model vehicle hoods, trunks, airplane doors or other closure panels. The hinge assembly includes at least one movable hinge arm and a spring assembly, and is adapted for simplified modification or customization to provide a selected counterbalancing force having regard to the weight and/or configuration of the closure panel. The spring assembly includes a torsion coil spring which is maintained under spring tension, and which is operable to resiliently bias a pivotally movable toggle arm used to translate spring forces to the movable hinge arm. The spring and toggle arm constructions are selected to assist in maintaining the closure panel in a desired position to prevent the unintentional movement of the hinge arms against forces selected less than a predetermined threshold force.

BACKGROUND OF THE INVENTION

In automobile manufacture, hinge assemblies are used to pivotally secure closure panels such as tailgates, trunk lids, bonnets and/or hoods to the vehicle frame, or any other type of closure. Conventional car hinges consist of a pair of steel hinge aπns which are movably connected to each other by one or more pivots, and which are bolted respectively to one of the closure panel and the car frame. To maintain the car hood in an open position, as for example to permit servicing of the engine, it is known to provide

counterbalancing springs, or alternatively supplementary gas-charged struts or a prop rod in conjunction with the hood hinges.

In conventional vehicle hinge constructions, tensioned-coil springs are used to provide counterbalancing forces to the weight of the vehicle hood or trunk. Each spring end is respectively secured to the vehicle frame and at a distal end of the moving hinge arm so as to be stretched under tension as the hood/trunk is closed. Difficulties exist with conventional tensioned-coil springs in that different vehicle models are provided with vehicle hoods and trunks having differing sizes and weights. As a result, heretofore it has been necessary to individually manufacture and assemble vehicle hinge assemblies for each specific vehicle model using different springs and/or hinge arm components, depending on the overall weight and size of the hood or trunk to be used. This has resulted in increased manufacturing inefficiencies and costs.

The use of hinge mechanisms in conjunction with gas-charged struts advantageously enables the hood to be opened or closed by only one hand of the user. As the hood is opened, gas pressure within the strut acts as a counterbalance to the weight of the hood, and helps to open and hold open the hood/closure panel by supporting the weight of the hood through the force generated by gas pressures within the struts. To close the hood, the user merely applies an added minimum downward pressure on the hood which is sufficient to overcome the resistive force of the struts. Gas struts suffer disadvantages, however, in that like conventional tensioned-coil spring hinges, it is necessary to tailor the individual size of each gas strut for different vehicle models having regard to the closure panel size and weight. In addition, over time as a result of wear and seal failures, the struts tend to lose their effectiveness and may require replacement. As a practical matter, the increased manufacturing costs of gas struts has resulted in their limited use to date. In particular, gas struts are used almost solely with more expensive luxury automobiles, sport utility vehicles and/or vehicles designed with ergonomic difficulties for the end user to open or close the closure panel.

Conventional hood hinge assemblies used with less expensive vehicles are most often provided in conjunction with an elongated prop rod which is hingely mounted

along the front of the vehicle under the hood. These hinge systems suffer the disadvantage in that they require two handed operation. In particular, in use, it is necessary to hold open the hood with one hand, and thereafter release, raise and position the prop rod with the other hand, typically orienting the end of the prop rod within a slot or opening formed in a forward underside portion of the hood. When closing the hood, two hands must again be employed, with one hand used to partially raise the hood a certain amount to allow the upper end of the prop rod to be disengaged from the hood slot, and the other to simultaneously lower and reposition the prop rod in a storage operation.

SUMMARY OF THE INVENTION

To at least partially overcome some of the disadvantages associated with prior art devices, the present invention seeks to provide a hinge assembly for a closure panel which is tunable, or which otherwise may be easily customized or modified to provide a pre-selected counterbalancing force, depending on the size, weight and/or mounting configuration of a selected closure panel.

Preferably, the present hinge assembly is provided with a generally standard sized or stock torsion-coil spring which is provided as an adjustable preassembly adapted for use with a number of different and interchangeable toggle arms used to translate spring forces either directly or indirectly to a movable hinge arm. By selecting a given toggle arm, a single spring assembly may be used for opening and closing of not only a variety of different model vehicle hoods having different sizes and/or weights, but also, trunks deck lids, hatchbacks, tail and tailgates, baggage compartment doors, airplane doors, furniture lids or other such closure panel (hereinafter generally referred to as closure panels).

In vehicle applications, the hinge assembly is most preferably operable by a user using only one hand, and without the need for either gas-charged struts or conventional prop rods to secure the raised closure panel in place in an open position against closure or downward forces which are less than a selected predetermined threshold force.

Another object of the invention is to provide a hinge assembly which is adapted to secure a vehicle closure panel in an open position over an opening, and which includes a spring pre-assembly which is provided with a torsion spring operable to resiliently bias an interchangeable pivotable earning or toggle arm used to bias the hinge arms to an open position, and provide a counterbalancing spring force to the weight of the vehicle closure panel.

Another object of the invention is to provide a hinge assembly for use in connecting a closure panel to a frame, and which includes a pair of pivotally movable hinge arms, and a spring assembly for securing the hinge arms in an open orientation, and which is tunable to permit adjustment in the spring force applied either directly or indirectly to at least one of the hinge arms.

Still another object of the invention is to provide a hinge assembly which is adapted for use in securing a vehicle hood, trunk or tailgate to a vehicle frame, and which may be easily modified or tunable for use on a variety of different automobiles to provide a counterbalancing force which has a similar feel to gas charged struts.

A further object of the invention is to provide a locking hinge assembly which possesses simplified design for use in securing a closure panel in a locked open orientation, and which may be unlocked by the one-handed application of a predetermined minimum threshold downward force, allowing the closure panel to be closed in a simplified downward movement.

In a simplified construction, the invention provides a hinge assembly having one or more pivotally movable hinge arms and a spring for resiliently biasing the hinge arms to an open or closed position. The spring is used to resiliently bias a earning or toggle arm which is directly or indirectly coupled to at least one hinge arm, and which has a length and/or shape selected to provide an opening or closing force thereon. Most preferably, the earning or toggle arm has a length and/or shape selected to translate spring forces to the hinge arm with a preselected force profile which is chosen having

regard to closure panel criteria which may include panel weight, panel size, and the hinge mounting positioning relative to the frame and/or closure panel.

Optionally, the hinge assembly may be used for a vehicle and include a prop arm coupled to at least one hinge arm, and which is provided with a bearing stud, flange, pin, guide member, releasable toggle, locking tab member or pawl (hereinafter collectively and generally referred to as a bearing stud). The bearing stud is engageable by the spring biased toggle arm so as to secure the vehicle hood and/or trunk in an open position against accidental closure. Most preferably, the prop arm is configured to allow the release of the hinge assembly by applying a simple downward force greater than predetermined threshold force, to thereby allow closing in final securement of the hood/trunk with a user standing in front or behind the vehicle.

Where a locking-type hinge is to be provided, the hinge assembly prop arm includes the spring biased bearing stud secured thereto, with the bearing stud being slidable to assist in the securement of a prop arm in an engaging position, where the prop rod prevents against accidental hinge closure. Preferably, the bearing stud is movable relative to a guide track or slot from an operational section which allows for manual opening and closing of the closure panel in a conventional manner, without the spring significantly affecting hinge operation, into an engaged section, whereby the spring supplies at least a partial force on the prop arm to urge the hinge towards an open orientation.

In another embodiment, the hinge assembly includes a spring preassembly which is provided as substantially stock, modular construction which is used to resiliently bias a preselected and/or interchangeable toggle arm used to translate counterbalancing spring forces to one or more movable hinge arms. The selected toggle arm has a shape and/or profile chosen to provide a force against the bearing stud which corresponds to a preselected counterbalancing force profile chosen for the specific type and/or size of vehicle bonnet, hood, trunk or deck lid, hatchback, lift back, lift or other closure panel to be secured in an open orientation. In operation, the spring preassembly and toggle arm provide an upward counterbalancing force to at least partially offset the dead weight of

the closure panel, without requiring substitution or customization of the hinge spring with different vehicle models.

In vehicle applications, a pair of automobile hinge assemblies are typically provided for coupling a vehicle hood to the vehicle frame. The hinge assemblies most preferably include a torsion spring assembly which includes a torsion spring used to bias the interchangeable toggle arm which is selected having regard to a preselected optimum force profile for a particular vehicle hood. Preferably, the toggle arm profile is chosen to provide a counterbalancing force greater than the downward force applied by the weight of the vehicle hood once the hood has been manually raised to a pre-selected angle, to effect further hood opening with minimal or no further manual lifting forces by a user.

In one possible construction, the hinge assembly includes a pivotally movable hinge arm which is typically fixedly connected to the movable closure panel. The movable hinge arm is directly or indirectly secured for relative pivotal movement to a hinge mount or second arm member by way of a pivot. The hinge mount may in turn be movable, but more typically is fixed, as for example in the case of vehicle applications to the vehicle frame adjacent a trunk or hood opening. The movable hinge arm extends from a proximal end which is pivotally coupled for rotational movement relative to the hinge mount about an arm pivot, to a distalmost end spaced therefrom. Although not essential, most preferably the toggle arm is provided as an elongated arm member and includes a linear or curing contact surface which is provided in engaging contact with the bearing stud, and which is either indirectly or directly coupled to the movable arm member. The spring assembly is secured in a fixed position relative to the hinge mount. The spring assembly is preferably provided with a torsion coil spring which is used to resiliently bias the movable hinge arm to either an open or closed position. Most preferably, the spring assembly is provided as a preassembly or modular unit which includes a torsion coil spring, a locking member or cap used to fixedly secure an end of the spring and maintain it under tension, and a mounting shaft or stud used in the securement of the spring preassembly relative to the movable hinge arm. The toggle member may be presupplied with the hinge preassembly or provided as a separate component for later coupling thereto. In assembly, the toggle member is provided for

reciprocal movement about a pivot axis which preferably is co-axially aligned with the axial centre of the body of the torsion spring and the mounting shaft axis. A movable end of the coil spring is coupled to the toggle arm to resiliently urge a resilient spring force thereon in a forward direction.

In automobile applications, the spring assembly used in the hinge may be provided as an adjustable construction with the torsion spring and locking cap being provided as generally standard components. The applicant has appreciated that by varying the shape and length of the toggle arm, as well as the location of the toggle pivot relative to the hinge pivot axis, it is possible to tune or customize the hinge for individual vehicle applications by simply altering the toggle arm used in the hinge in response to changes in the closure panel weight, size and/or hinge mounting configuration. In particular, it is possible to tune the hinge to provide a preselected force profile on the movable ami by adjusting the toggle arm pivot locations and contact surface profiles.

Each hinge assembly is provided with upper and lower hinge brackets, plates or arms (hereinafter generally referred to as hinge arms), which respectively are either integrated into or positioned for coupling directly or indirectly to the closure panel and the adjacent frame. The upper and lower hinge arms are pivotally connected towards their rearward ends for movement relative to each other either by one or more hinge pivots or pins, or for compound pivotal movement about a hinge pivot axis by way of one or more linkage arms pivotally connected to each other at points along the hinge arms.

In embodiments where the hinge assembly is provided with a prop arm, generally elongated slot, track or other guidance member (hereinafter collectively and generally referred to as a guide slot) may be formed either as a separate member connected to the closure panel or frame, or more preferably is formed on or in the second other hinge arm, with the hinge assembly formed as a pre-manufactured integral unit. The prop arm may be pivotally coupled towards its first end to either the closure panel or the vehicle frame. More preferably, however, the first end of the prop arm is pivotally secured to a forward portion of a first one of the hinge arms at a point spaced a distance

forwardly from one or more of the hinge pivot axis. The bearing stud is secured toward the second other end of the prop arm, so as to be engageable by the toggle arm as it moves therein. The bearing stud is slidable along the guide slot so as to be reciprocally movable therealong as the hinge arms are moved between fully closed and fully open positions, with the relative positioning of the bearing along the guide slot is used to achieve either free movement or locking the hinge assembly in an open position under normal load forces.

The applicant has appreciated that by introducing minor changes to the orientation and curvature of the toggle arm and/or the guide slot and/or the position of pivotal coupling of the prop ann, adjustments may be made to the hinge assembly to match a pre-selected hinge force profile for a particular application. This effectively allows the hinge to be turned without significantly changing or altering the spring tension. This enables the use of the hinge assembly to be adjusted to provide an optimum counterbalancing force for a particular application, or event for use with different vehicle models and/or makes.

In a simplified design, the guide slot includes a free operational section and an engaged section. In the free operational section, the toggle arm most preferably generally passively engages the bearing member such that the hinge assembly operates so as to allow the closure panel to be manually opened and closed in a conventional manner without being substantially affected by the spring. In the engaged section, the toggle arm urges the bearing member forwardly along its path of movement to provide a positive counterbalancing force on the closure panel, as for example, to assist in preventing movement of the closure panel from open orientation under its own weight. In another aspect, the slot is formed with an operational section which is generally elongated and extends forwardly from a rearwardmost bight spaced towards the hinge pivot axis to merge at its forwardmost end with the engaged section. The operational section may be straight, angled and/or curved. Most preferably, the operational section is formed as a parallel sided guide slot and is oriented to allow reciprocal movement of the bearing stud therealong. More preferably, the engaged section of the guide slot extends in a generally arcuate or otherwise partially transverse direction to the operating

section. Optionally, the engaged portion may also include upper and/or lower detent portions which physically allow the bearing stud to move therein to assist in allowing the closure panel to move to a more fully open position, allowing greater access to the vehicle.

Although not essential, preferably the toggle member is configured to either disengage from or largely passively engage the bearing stud as it moves along the operational section of the guide slot, with the hinge assembly operating as a largely conventional hinge as the bearing stud locates therein. Most preferably, in the operational section, the bearing stud does not place increased winding stresses on the spring so not to otherwise over tension the spring. The applicant has appreciated that by limiting the biasing force on the toggle arm in the operational section, the closure panel is not placed under significant stress and thereby, for example, allowing the vehicle hood, lift gate or the like to be manufactured less robustly and more inexpensively.

As the bearing stud moves into the engaged section of the slot, the toggle arm actively engages the bearing stud to provide a gradually increasing positive biasing force thereon, urging the bearing member forwardly. It is to be appreciated that the biasing force of the spring on the slidable second end of the prop arm results in a forward force thereon. Preferably, the forward force increases to a point which is selected to act as a counterbalance weight of the closure panel and assist in moving the closure panel to and from the open configuration.

It is furthermore to be appreciated that comparatively smaller spring constructions may be used with differential coil spacing and/or thickness to provide variable counterbalancing effects, as for example, the hinge assembly is opened past and/or between predetermined threshold amounts.

In a simplified construction, the hinge assembly is used as a vehicle hood hinge. The guide slot is formed in the lower hinge arm so as to extend forwardly from a rear portion spaced towards the pivot axis, to a forwardmost end portion, with the prop arm being pivotally connected towards a forward end of the upper hinge arm. It is to be

appreciated, however, that the hinge assembly could equally be provided in the reverse orientation, with the prop arm pivotally fixed to the lower hinge arm or even the vehicle frame, and the guide slot provided along the length of the upper hinge arm or formed in the hood. As the hood is raised, and the upper hinge arm is pivoted relative to the lower arm about the hinge pivot and pivot axis, the relative movement of the hinge arms results in the second end of the prop arm and the sliding member being slid forwardly along the operational section of the guide slot.

In a preferred embodiment, the engaged section of the guide slot extends forwardly along a generally arcuate curving path which extends radially about a path axis. The spring biased toggle arm is pivotally secured to the hinge assembly with the toggle pivot axis spaced from and generally parallel to the hinge pivot axis. Although not essential, most preferably the toggle arm is provided with a generally non-linearly or curving engagement surface which is configured for engaging contact with the sliding member as it reciprocally moves along the slot. The toggle member is resiliently movable between an initial biased position, where the engagement surface of the toggle arm is moved adjacent to a side of the operational section of the guide slot so as not to substantially interfere with the sliding movement of the guide member thereon, to an engagement position, wherein the engagement surface is positioned in an orientation at least partially transverse to the direction of elongation of the slot. As the sliding member moves from the operational section of the slot into the engaged section, the rotational movement of the toggle member about the toggle pivot axis and contact between the engagement surface and sliding member applies an increasing forward force on the sliding member, reaching a predetermined force to urge the sliding member to move forwardly along the guide slot. This forward movement of the guide member results in the prop arm forcing the hinge arms apart, moving the closure panel towards the open position.

The applicant has appreciated that by adjusting the curvature or angle of the guide slot path and/or the shape of the contact surface of the toggle member or length of the pivot arm may also be used to tune the hinge for use in different applications and/or with different vehicle hoods, lift gates or the like. As such, the present hinge

construction provides greater versatility enabling the same hinge parts to be used on a variety of different vehicle types or models with minor adjustment to one or more hinge components such as the spring, guide slot, prop arm and/or toggle arm.

Optionally, the engaged section of the guide slot may include an upper extending detent at its forwardmost end. As the hinge arms move to the fully opened position, the guide member is urged into alignment with the detent, so as to be movable therein to allow the hood to be opened to a greater than normal angle to facilitate access.

In another possible construction, a keeper recess, catch arm, locking hook or other catch member may be used to engage the guide member as it moves to the forward end of the slot, to assist in locking the hinge arms in an open configuration.

To close the vehicle hood, a manual downward force is applied on the hood which is sufficient to move the sliding member downwardly out of alignment with the detent, if any, and rearwardly along the slot, and which exceeds the upward counterbalancing force applied thereagainst the toggle arm. The downward movement of the upper hinge arm results in the bearing stud returning rearwardly along the engaged section of the guide slot against the bias of the toggle arm and spring. Movement of the bearing stud along the slot most preferably results in the toggle arm being repositioned, rotating rearwardly about the toggle pivot axis to reassume an orientation with its engagement surface parallel to a section of the slot. As the bearing stud returns towards the operational section of the slot, most preferably the toggle arm provides a gradually decreasing forward force on the bearing stud, most preferably reaching a neutral or zero forward force thereon as the bearing stud returns into the operational section of the slot. Once so positioned, the bearing stud is again passively engaged, so as to freely move along the operational section of the slot without being subjected to significant forward forces. The applicant has appreciated that while not essential, here the effect of the spring on the bearing stud is minimized, eliminating the need of overtensioning the spring, and lengthening spring life. In addition, the present construction advantageously permits the use of comparatively smaller springs as contrasted with conventional spring triggered hood release mechanisms, enabling the entire hinge assembly to be formed

with an overall more compact design Optionally, the bearing stud may be provided with a live bearing to minimize any fπctional wear, resulting from the contact forces applied by the toggle arm thereon as it moves long the guide slot

Accordingly, in another aspect the present invention resides in a hinge assembly including a hinge mount and a hmge arm pivotally coupled to said hmge mount,

a spring assembly for resihently urging the hmge arm in pivotal movement relative to the hmge mount from a first biased closed orientation towards a second open orientation moved relative thereto, the spring assembly including a spring, a locking plate and a coupling assembly,

the spring extending in a generally helical direction radially about an axis from a first spring end portion to a second spring end portion to define a generally cylindrical spring-coil body, the spring body being generally elongated longitudinally along said axis,

the locking plate being coupled to the first end portion to limit movement of the first end portion radially relative to said axis,

the second end portion providing a resilient biasing force to assist in moving said hinge arm from said closed orientation to said open orientation,

with said hmge arm in said closed orientation, the second end portion being moved to a first radial position relative to said axis, and wherein when said hinge arm is moved to said open orientation, the second end portion being moved in an opposite direction to the helical direction to a second radial position relative to said axis,

the coupling assembly substantially retaining the locking plate in a fixed position lelative the hmge mount

In yet another aspect, the present invention resides in a vehicle hmge assembly for pivotally securing a closure panel to a vehicle frame, the hinge assembly including, a

generally fixed hinge arm, a movable hinge arm pivotally coupled to the fixed hinge arm for movement about a hinge pivot axis between open position and a closed position, a bearing stud being in connection with the moveable hinge arm, a spring assembly including a torsion coil spring and locking cap, the spring extending generally helically about a spring axis from a first spring end portion to a second spring end portion, the spring being secured relative to said fixed hinge arm with the spring axis being spaced from and generally parallel to the hinge axis, the locking cap for maintaining said spring under tension, said first end portion being coupled to said locking cap against substantial movement radially relative to said spring axis, the second end of the spring being resiliently movable radially about said spring axis between a first biased position and second biased position radially spaced from the first biased position, a toggle engaged by the second end and being secured for pivotal movement relative to said fixed arm, the toggle arm including an engagement surface configured for engaging contact with said bearing stud to bias the movable hinge arm in movement from the closed position to the open position.

In still a further aspect, the present invention resides in a vehicle hinge assembly for hingely securing a closure panel to a vehicle frame, the hinge assembly including a hinge bracket fixedly mounted the vehicle frame and a hinge arm pivotally coupled for movement relative to said hinge mount, a spring assembly for resiliently urging the hinge arm in pivotal movement relative to the hinge mount from a first biased closed orientation towards a second open orientation, the spring assembly including a torsion coil spring, a locking cap and a mounting shaft secured to the hinge bracket, at least part of the torsion coil spring extending in a generally helical direction radially about the mounting shaft from a first spring end portion to a second spring end portion, the locking cap being securable in a substantially fixed position relative to the hinge bracket, the first end portion being secured to the cap to substantially prevent movement of the first end portion radially relative to said shaft, a toggle arm pivotally secured to the shaft, the toggle arm having an engagement surface configured for engaging contact with said arm to transmit biasing forces of said spring to said hinge arm, the second end portion of the spring resiliently biasing the toggle arm to assist in moving said hinge arm from said closed orientation to said open orientation, with said hinge arm in said closed orientation,

the toggle arm and second end portion being moved to a first radial position relative to said shaft, and wherein when said hinge arm is moved to said open orientation, the toggle arm and second end portion being moved to a second radial position relative to said shaft.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference may now be had to the following detailed description taken together with the accompanying drawings in which:

Figure 1 illustrates a perspective view of an automobile incorporating a pair of integrated hinge assemblies in accordance with a preferred embodiment of the invention;

Figure 2 illustrates schematically a hinge assembly used in the automobile of Figure 1 illustrating the range of relative motion of the hinge arms between fully opened and fully closed positions;

Figure 3 illustrates a perspective view of the hinge assembly shown in Figure 2 with the hinge arms positioned in an initial fully closed orientation;

Figure 4 illustrates a partial exploded view of the spring preassembly and a prop arm used in the hinge assembly of Figure 3 in biasing the hinge arms in a fully open configuration;

Figure 5 illustrates a schematic first side view of the hinge assembly of Figure 3 with the hinge arms positioned in the initial fully closed orientation;

Figure 6 illustrates a schematic side view of the hinge assembly shown in Figure 5 with the hinge arms moved in an initial partially opened position;

Figure 7 illustrates a schematic side view of the hinge assembly shown in Figure 5 with the hinge arms moved past a threshold open position wherein the toggle assembly provides a counterbalancing opening force thereon;

Figure 8 illustrates a schematic side view of the hinge assembly of Figure 5 with the hinge arms positioned in a fully opened configuration;

Figure 9 illustrates a schematic side view of a hinge assembly for a vehicle hood in accordance with another embodiment of the invention;

Figure 10 shows a schematic perspective view of a hinge assembly in accordance with a further embodiment of the invention for use with a vehicle trunk;

Figure 1 1 illustrates an exploded view of the hinge assembly as shown in Figure 10; and

Figure 12 illustrates graphically a sample preselected force profile for the hinge assembly shown in Figure 10 in accordance with a preferred embodiment of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference is first made to Figure 1 which illustrates a vehicle 8 employing a pair of integrated hinge assemblies 10 used to pivotally secure a vehicle hood 12 at each of its sides to a car frame 14. The hinge assemblies 10 are configured to enable a user, using one hand, to both raise and secure the hood 12 in the fully opened position shown in Figure 1 relative to the car frame 14, while enabling the hood 12 to be closed and secured from the front of the vehicle 8 by applying a predetermined minimum downward force thereon.

More particularly, as will be described, as shown best in Figure 2, the hinge assemblies 10 are provided such that once the hood 12 (Figure 1) is manually partially opened to a threshold angle α, the hinge assemblies 10 thereafter provide a combined counterbalancing upward force which is equal to and preferably greater than the downward force applied by the weight of the hood 12, to automatically raise or assist in raising the hood 12 to the fully opened position of angle β. As a result, once the hood 12

is raised to a critical angle, and preferably a critical angle α selected at between about 10 to 40°, and preferably about 12 and 20°, the hinge assemblies 10 alone are operable to self raise the hood 12 the remaining distance (angle β) without further manual effort, or with manual effort depending on manufacturer requirements.

Figures 3 to 8 illustrate the left-hand hinge assembly 10 used to hingely couple the hood 12 to the car frame 14, it being appreciated that the right-hand hinge assembly is formed having the mirror construction, and operates in the identical manner.

The hinge assembly 10 is most preferably provided and installed as a preassembled unit and includes a movable upper hinge bracket or arm 18 which is adapted for securement to the hood 12, and a fixed lower hinge bracket or arm 20 which is provided for mounting directly to the car frame 14. The upper and lower hinge arms 18,20 are preferably fabricated from steel, aluminum or other suitable metals or alloys, and extend respectively from rearwardmost ends 22,24 to forwardmost ends 23,25. The hinge arms 18,20 are pivotally coupled directly to each other towards their respective rearwardmost ends 22,24 by way of a hinge pivot 26 so as to movably support the hood 12 in movement about a hinge axis A _H -A _H (Figure 4).

As shown best in the exploded view of Figure 4, a guide slot 30 is formed through the lower hinge arm 20. Although not essential, the guide slot 30 is most preferably characterized by generally equally spaced sidewalls. The guide slot 30 includes a laterally extending rolled edge 32 which, as will be described, is provided to minimize component wear and enhance the overall hinge assembly life. The guide slot 30 includes a generally linear operational section 34 and a generally arcuate engaged section 38. The operational section 34 extends forwardly and angularly upwardly from a rearwardmost end or bight 36 to merge at its forwardmost end with the initially upwardly and forward curving arcuate section 38. Most preferably the arcute engaged section 38 includes a portion which extends radially about a rotational path axis Ap-Ap (Figure 4) to a forwardmost upwardly projecting detent 40 at the forwardmost end of the slot 30. Although not required, the detent 40 advantageously permits the hood 12 to be moved to a more fully open position during vehicle assembly and manufacture.

Figure 3 shows the hinge assembly 10 as including a rigid steel prop arm 54. The prop arm 54 is pivotally secured at its first end portion towards the forwardmost end 23 of the upper hinge arm 18 by means of a prop arm pivot 62. A bearing stud or guide bearing 64 is rotatably secured to the second other end of the prop arm 54. The bearing stud 64 is sized so as to be rotatably received within the guide slot 30 for movement therealong. As shown best in Figure 3, the bearing stud 64 is provided with a live bearing 66 which extends laterally through the guide slot 30.

Figures 3 and 4 show best the lower hinge arm 20 as further having a spring assembly 42 mounted thereto. The spring assembly 42 has a toggle arm 44 secured thereto, and is most preferably formed with modular preassembly consisting of a coil torsion spring 46, a locking plate or cap 48, and an elongated mounting shaft 51.

The toggle arm 44 is provided with a projecting finger portion which includes non-linearly extending, curving engagement surface 50. The arm 44 is coupled to the mounting shaft 51 for pivotal movement relative to the hinge arm 20 generally about the rotational path axis Ap-Ap such that the engagement surface 50 contacts the bearing stud 64 while being movable in a path of movement at least generally aligned with the engaged section 38 of the slot 30. Although not essential, the curvature of the engagement surface 50 is selected so as to orient generally normal to the engaged section 38 of the slot 30, as the arm 44 moves therealong.

Torsion coil spring 46 is provided with end portions 52a,52b which engage respectively the toggle arm 44, and the locking cap 48 to provide a resilient biasing spring force on the toggle arm 44. In particular, the mounting shaft 51 is used to couple the toggle arm 44, spring 46 and locking cap 48 to the arm 20, such that the arm 44 is selectively movable about the axis Ap-Ap and relative to the shaft 51. In this configuration, the spring 46 extends from the end portion 52b in a generally helical direction radially about its winding axis, and which is co-axial with both the shaft 51 and the path axis A _P -A _P to the end portion 52a. The helical portion of the spring 46 defines a generally cylindrical spring-coil body 47 which is elongated longitudinally in the

direction of and radially centred about Ap-Ap. The mounting shaft 51 is preferably used to mount and secure the toggle arm 44, coil spring 46 and locking cap 48 directly to the hinge arm 20, such that the path axis Ap-Ap is spaced from and generally parallel to the hinge axis A _H -A _H -

As shown best in Figure 4, the shaft 51 includes an end portion which is insertable through an aperture 53 formed in a proximal end portion of the toggle arm 44. The second other end of the shaft 51 is coupled to the cap 48, with the spring body 47 secured in co-axial alignment with the shaft 51. The second shaft end 58 includes a bevel or keyway 55 sized for complementary mated insertion within an axially positioned cap opening 59 formed in the cap plate 48. It is to be appreciated that the mated positioning of the bevel or keyway 55 within the cap opening 59 is such as to fixedly secure the locking cap 48 to the shaft 51 against radial movement relative to the

With the spring assembly 42 secured to the hinge arm 20, end portion 52a of the torsion spring 46 is movable together with the toggle arm 44 radially about the rotational path axis Ap-Ap. In particular, the toggle arm 44 is biased in movement by the resiliency of the spring 46. The toggle arm 44 is thus movable from a first radial position where, for example, the engagement surface 50 is located to an orientation generally parallel to the operational section 34 of the slot, and a second orientation where the end portion 52a is displaced radially about the axis Ap-Ap in a direction opposite to the helical winding direction of the spring body 47 such that the engagement surface 50 moved towards the forwardmost bight 40. In this manner, the coil spring 46 resiliently biases the toggle arm 44 in the direction of arrow 100 (Figure 5) to resiliently urge the engagement surface 50 forwardly towards the actively engaging position and forwardmost bight 40 of the slot 30.

Most preferably, the arm 44 is reciprocally movable with the engagement surface 50 in engaging contact with the bearing stud 64 between a passively engaging position (shown in Figure 5) wherein the engagement surface 50 is moved to an orientation generally parallel to and adjacent to the operational section 34 of the slot 30; and an

actively engaging position (shown in Figure 7) wherein the engagement surface 50 is oriented at least transversely to the direction of elongation of the engaged section 38 so as to provide a force on the bearing stud 64 forwardly along the slot 30.

Although not essential, the locking cap 48 and spring end 52b are selectively positionable radially about the axis Ap-Ap relative to the spring end portion 52a and toggle arm 44. As such, by altering the position of the locking cap 48 radially relative to the hinge arm 20, it is possible to increase or decrease the tension applied by the spring 46 on the toggle arm 44 having regard to the size and/or weight of the vehicle hood 12. As such, by varying the tensioning of the spring force, the hinge assembly 10 may be fine tuned to adjust either the counterbalancing force applied to a number of different vehicle hoods 12 and/or optionally to adjust each individual hinge at the time of manufacture and/or installation to provide a tightly controlled preselected hinge force.

As shown best in Figure 3, the live bearing 66 is provided such that in assembly, it rotatably contacts both the rolled edge 32 and an engagement surface 50 of the toggle arm 44 to minimize component wear as the hinge arms 18,20 are opened and closed. It is to be appreciated that other bearing constructions could, however, be used.

In operation, the toggle assembly 42 selectively provides an upward opening force on the upper hinge arm 18, as the bearing stud 64 is moved from the operational section 34 and into the arcuate engaged section 38 of the slot 30. Figures 5 to 8 show best the hinge arms 18,20 as the forwardmost ends 23,25 are moved relative to each other about the hinge axis A _H -A _H as the hinge assembly 10 is opened and closed. It is to be appreciated that as the hinge arms 18,20 are opened and closed, the pivotal coupling of the prop arm 54 to the upper hinge arm 18 results in the bearing stud 64 reciprocally moving along the guide slot 30 to extend or collapse the prop arm 54.

Figure 5 shows the hinge assembly 10, initially when the hood 12 is fully closed, and the hinge arms 18,20 are oriented with their forwardmost ends 23,25 substantially in juxtaposed alignment at angle 0 (Figure 2). In this position, the prop arm 54 is generally co-aligned with the hinge arm 18 and the bearing stud 64 of the prop arm 54 is moved

rearwardly along the guide slot 30, locating immediately adjacent to the rearward bight 36

As the hood 12 is initially raised, the upward pivoting movement of the hinge arm 18 relative to hmge arm 20 results in the forward sliding of the bearing stud 64 along the operational section 34 of the guide slot 30 While the bearing stud 64 moves along the operational section 34, the engagement surface 50 of the toggle arm 42 is maintained in a parallel orientation to the direction of elongation of the operational section 34 by its engagement with the bearing stud 64 In this orientation, the toggle assembly 42 passively engages the bearing stud 64, applying a neutral or zero forward force thereon in a direction which is lateral to the slot direction, and which otherwise does not provide a significant resistive or positive force on the initial opening of the hood 12 As a result, while the guide bearing 64 locates withm the operational section 34, and until the hood 12 is raised to threshold angle α, the hood 12 is lifted and lowered in a conventional manner, with the user providing the necessary manual upward lifting force thereon

The continued upward lifting of the hood 12 effects movement of the bearing stud 64 into the arcuate engaged section 38, as the hood 12 is raised to the threshold angle α As shown best in Figures 7 and 8, as the bearing stud 64 moves into and along the arcuate section 38, the resilient force of the spring 46 urges the toggle aπn 44 in the counter clockwise direction of arrow 100 about the rotational path axis Ap-Ap As a result, the engagement surface 50 is moved relative to and rearwardly of the bearing stud 64 so as to apply a gradually increasing forward force thereon, reaching a predetermined minimum force when the toggle arm 44 fully engages the bearing stud 64 such that the rear surface of the bearing stud 64 is directly forward of and engaged by the toggle arm 44 In this orientation, the toggle arm 44 provides a forward force on the bearing stud 64 which is generally aligned with the orientation of the guide slot, to drive the bearing stud 64 forwardly therealong The forward force on the bearing stud 64 acts to cause the pi op aπn 54 to further torce the hinge arm 18 upwardly, until the bearing stud 64 reaches the forward end of the slot 30 and the hinge arms 18,20 and at the fully opened angle β As the bearing stud 64 moves to the forwardmost end of the slot 30, the bearing stud 64 is positioned in alignment with the detent 40

Most preferably, the spring 46 is provided with a spring tension which is selected such that when the bearing studs 64 are fully engaged by the toggle arm 44, the cumulative force of engaging contact between the toggle arm 44 and bearing studs 64 of the hinge arms 10 is generally equal to or greater than the rearward force applied by the downward weight of the hood 12 on the bearing stud 64 in the reverse direction. As a result, the springs 46 of the hinge assembly 10 allow the hood 12 to be manually raised with only minimum effort, or more preferably self raise the hood 12 open in movement once it has been manually raised to the threshold position α to the fully opened position shown in Figure 1.

To close the vehicle hood 12 and return the hinge assemblies 10 to the initial position of Figure 5, the user (not shown) applies a predetermined minimum downward force on the hood 12. The downward force is selected sufficient to urge the bearing stud 64 rearwardly against the force of the spring 46 out of alignment with the detent 40, and in the reverse direction of arrow 100 against the forward upward force of the toggle arm 44. As the downward force is applied, the engagement between the bearing stud 64 and the engagement surface 50, rotates the toggle arm 44 clockwise in the reverse direction against the bias of the torsion spring 46 to reposition the engagement surface 50 of the toggle arm 44 in an orientation aligned with the longitudinal extent of the operation section 34 as shown in Figure 6. It is to be appreciated that in closing, the spring 46 similarly provides a counterbalancing force against the weight of the vehicle hood 12 with the toggle arm 44 providing a decreasing forward force on the bearing stud 64 in the reverse manner, to prevent it from being lowered too quickly. Once the hood 12 is lowered to the threshold angle α and whereby the toggle arm 44 again passively contacts the guide bearing 64, the hood 12 may be closed via gravity in a conventional manner.

It is to be appreciated that by forming the operational section 34 as an angularly extending linear section allows the hood 12 to be fully closed without over-tensioning of the torsion spring 46. It is to be appreciated that in an alternate construction, the operational section of the guide slot 30 could be formed with a curving or other arcuate

configuration, or omitted in its entirety, without departing from the spirit and scope of the invention.

The present hinge assembly 10 is suitable for use with a variety of different model vehicle hoods 12 having different sizes and/or weights, to provide differing counterbalancing forces, without requiring the substitution or insertion of customized spring components, or other modifications to the hinge assembly 10.

Similarly, although Figures 5 to 8 illustrate the guide slot 30 as extending angularly and then curving upwardly, the invention is not so limited. Hinge assemblies 10 having differently shaped guide slots may also be used, or if desired, the guide slot 30 and prop ami 54 could be omitted in their entirety.

Reference may be had to Figure 9 which illustrates a further embodiment, wherein like reference numerals are used to identify like components. Figure 9 illustrates a hinge assembly 10 adapted for use with a vehicle hood 12 (Figure 1) and which as operable to effect the lifting of the rear edge 210 of the hood 12 in the event of impact with a pedestrian. In particular, various vehicle manufacturers have proposed the raising of the rear portion of the hood 12 as a means of cushioning pedestrian/vehicle impact forces, to lessen the severity of impact injuries.

In Figure 9, the guide slot 30 is provided with a vertically extending detent channel 230. The detent channel 230 is open to the rearwardmost end of the operational section 34 of the slot 30. A detent lever 232 is provided which extends from a detent pivot 234 downwardly to a lower end 236. A series of detent notches or locking ribs 240a,240b are used to engage the pivot 234 so as to substantially prevent movement of the detent lever 232 thereabout. As shown in Figure 9, the lower end 236 is thus normally aligned with the opening into the detent channel 230 so as to prevent movement of the bearing stud 64 therein. In this position, the detent lever 232 is non- moving and functions as the upper edge of the operational section 34, such that the toggle arm 44 acts on the bearing stud 64 in the same manner as described with reference to Figures 3 to 8.

In the event of an impact, the hood 12 is initially pushed rearwardly. An actuator (not shown) and/or impact forces effects disengagement of the detent notches 240a,240b from the detent pivot 234. This in turn detaches the detent lever 232 from the lower hinge arm 20, leaving it attached only to the upper hinge arm 18 and allowing pivotal movement of the lower end 236 out of alignment with the channel 230. With the lower end 236 so moved, the bias of the spring 46 results in the toggle arm 44 rotating forwardly to slide the bearing stud 64 upwardly into channel 230. The bearing stud 64 is provided so that its upward movement results in its engaging contact with the hinge arm 18, so as to raise both the hinge arm 18 and rear edge 210 therewith under the resilient bias of the spring 46. The raised rear edge 210 cushioning contact forces and assisting in protecting pedestrians at the time of impact with the hood 12.

While the detailed description of the embodiment illustrates the hinge assembly as including a torsion spring used to provide a biasing force on the toggle arm 44, the invention is not so limited. It is to be appreciated that various other types of biasing apparatus and/or members may also be employed without departing from the spirit and scope of the invention. Such devices would include, without limitation, electric motors, as well as single or multiple compression and tension coil springs, leaf springs, gas springs, gas shocks, and the like, either alone or in combination.

Reference may be had to Figures 10 and 11 which illustrate an alternate hinge assembly 10 construction in accordance with another embodiment of the invention, wherein like reference numerals are used to identify like components. Figures 10 and 1 1 illustrate a hinge assembly 10 for use in hingely securing the trunk 1 12 (Figure 1 ) of the vehicle 8 to the vehicle frame 14. The hinge assembly 10 includes a fixed hinge bracket mount or arm 20 which is adapted for mounting to the car frame 14, and a movable hinge arm 18 which is coupled to trunk 112, and which is pivotally secured to hinge arm 20 by hinge pivot 26, for movement about axis A _H -A _H .

The spring preassembly 142 is preferably provided as a modular component which incorporates a standard torsion spring 46, a locking plate or cap 48 and a mounting shaft 51.

In the construction shown in Figures 10 and 1 1, the hinge assembly 10 is provided without the guide slot 30 and prop arm 54. Rather, the coil torsion spring 46 of the spring assembly 42 is used to resiliently bias toggle arm 44 against a bearing stud 64 mounted directly on arm 18, to provide the desired predetermined counterbalancing force to offset the weight of the trunk 1 12.

An inner end of the shaft 51 is secured to the hinge arm 20 and used to rotatably secure the toggle arm 44 for rotational movement relative to the hinge arm 20, in a position interposed between the arm 20 and the spring body 47. As with the embodiment shown in Figure 3, the toggle arm 44 is mounted so as to be rotatable about the shaft 51 and radial path axis Ap-Ap, with the spring end 52a being secured thereto.

The locking cap 48 is fixedly coupled to the second out shaft end by the fitted insertion of the shaft bevel 55 within the cap aperture 59. The cap 48 secures the spring end 52b thereto against rotation relative to the path axis Ap-Ap. The locking cap 48 is again preferably positionable radially relative to the hinge arm 20 to permit fine adjustment of the spring 46 to maintain a desired winding tension.

It is to be appreciated that with the hinge assembly 10 shown in Figures 10 and 1 1 , the torsion spring 46 resiliently biases the toggle arm 44 in forward rotational movement in the direction of arrow 200 (Figure 10) about the path axis A _P -A _P . The toggle arm 44 in turn translates spring forces to the bearing stud 64 and hinge arm 18. The toggle arm 44 thus provides a counterbalancing force to the weight of the trunk 112.

As the toggle ami 44 rotates forwardly in the direction of arrow 200, the engagement surface 50 of the arm 44 is most preferably selectively repositioned between passively engaging and actively engaging positions. In particular, when the toggle arm 44 is moved to an orientation passively engaging the bearing stud 64, the engagement surface 50 is moved towards an orientation more parallel to the direction of radial movement of the stud 64, such that spring forces are tangentially applied to the arm 18.

As the trunk 112 is opened, the engagement surface 50 is repositioned relative to the radial path about which the bearing stud 64 moves, to assume an orientation actively engaging the bearing stud 64, and generally transverse to its path of movement. In the engaging configuration, contact between the arm 44 and the bearing stud 64 results in a more direct application of spring force on the hinge arm 20. Preferably such active engagement results in the toggle arm 44 using the hinge arm 18 in rotational movement about the hinge pivot 26 under the force of the spring 26, and with a force greater than the downward force applied by the weight of the trunk 112.

As the hinge pivot A _H -A _H and path axis Ap-Ap are offset relative to each other, the arm 44 is chosen with an engagement surface 50 having a profile selected to engage the bearing stud 64 with an opening force profile which is preselected having regard to the particular trunk panel weight, shape and/or the mounting locations for the hinge assembly 10 relative to the trunk 1 12 and/or from 14. Most preferably, the hinge assembly 10 is tunable by changing toggle arms 44, having different shape and/or sized engagement surfaces 50 to provide a predetermined opening force profile selected for an individual trunk 1 12 the closure panel. By way of example, Figure 11 illustrates graphically a preferred preselected profile for a selected vehicle trunk 112. In the preferred profile illustrated, when the hinge arms 18,20 are fully closed, the toggle arm 44 actively engages the bearing stud 64. The engagement surface 50 of the toggle arm 44 is provided in an orientation which is generally normal to the radial path of movement of the bearing stud 64. In this configuration, the torsion spring 46 exerts a positive counterbalancing force on the hinge arm 18 which preferably exceeds the trunk weight. As a result, the hinge assembly 10 is initially self-raising under the force of the uncoiling spring body 47 when the trunk 1 12 is first opened.

As the hinge assembly 10 is opened to a mid position, the engagement surface 50 is reoriented to a position which is generally aligned with the path of radial movement of the bearing stud 64, such that the hinge arm 20 is passively engaged. The repositioning of the engagement surface 50 results in a force on the stud 64 which most preferably is insufficient to provide a positive counterbalancing force to the weight of the trunk 1 12.

In this orientation, the trunk lid 1 12 will not move under the biasing force of the spring 46 without an additional manual force.

As the trunk 1 12 and hinge assembly 10 continues to be opened, as for example, to the indicated angle of 82° as shown in the graph of Figure 12, the engagement surface 50 is returned to an orientation actively engaging the bearing stud 64. Here the surface

50 is repositioned relative to the bearing stud 64 to an orientation towards a position normal to the radial path of movement of the stud 64. In this orientation, the spring 46 again provides a positive counterbalancing force which exceeds the downward force supplied by the weight of the trunk 1 12, to effect further self-raising of the vehicle trunk 1 12 to a fully opened configuration.

The applicant has appreciated that with the hinge assembly 10 shown in Figures 10 and 1 1 may be provided with the torsion spring 46, locking cap 48 and mounting shaft

51 formed as a preassembly substantially from stock or modular components. The applicant has appreciated that by altering the configuration of the toggle arm 44, and in particular the curvature and/or length of the engagement surface 50 and its mounting position relative to the bearing stud 64, the present hinge assembly 10 may be used with a variety of closure panels having different sizes and/or shapes with only minimal customization. The present invention advantageously permits the spring preassembly 142 to be used with a number of different and interchangeable toggle arms 44, without substantial modification to parts and/or designs by the substitution of a single component, and in particular the toggle arm 44. The hinge assembly 10 may thus be "tuned" to a specific predetermined optimal force profile for different vehicle trunks 1 12, hoods 12 or other types of closure panels, depending on the desired properties to be achieved.

While the Figures have described the integrated hinge assembly 10 as including upper and lower hinge arms 18,20 for simplification, it is to be appreciated that the hinge could be equally provided in inverted arrangement to that shown.

Although the preferred embodiment of the invention describes a hinge assembly 10 as having two pivot arms 18,20, the present invention could equally be used with other hinge assemblies having multiple hinge bar constructions, including those having pivotally connected linkage arms.

The construction of the present invention advantageously enables use of multiple hinge assemblies 10 in vehicle or other closure panel applications.

Although the detailed description describes the hinge assembly 10 as being used in the securement of vehicle hoods 12 and trunks 1 12, it is to be appreciated that the hinge assembly 10 is equally suitable for other applications. By way of non-limiting example, the hinge assembly could also be used in the hinged coupling of lift gates, hatchbacks, vehicle doors, or other closure access panels used in trucks, buses, automobiles, aircraft, railcars, furniture and the like, without departing from the spirit and scope of the invention. In use, the hinge assembly 10 may provide a counterbalancing force to lock or hold such closure panels in open or closed configurations relative against a predetermined threshold closure force without the need of separate support components, such as gas-charged struts or prop rods. Most preferably, the hinge assemblies 10 are selected such that the total counterbalancing force applied by the hinge assemblies 10 exceeds the closure force applied by the weight of the closure panel.

While the embodiment shown in Figures 3 to 8 shows the presence of a guide slot 30 formed in the lower hinge arm 20 as presenting a simplified construction, it is to be appreciated that the guide slot 30 could be provided in the upper hinge arm 18 or as a separate part or component altogether. Similarly, if desired, the prop arm 54 could be pivotally secured either directly to the hood 12 or closure panel, or to other closure panel elements apart from the upper hinge arm 18 without departing from the spirit and scope of the invention.

Although the detailed description describes the hinge assembly 10 as including a pair of hinge arms 18,20 which are provided for mechanical coupling to the vehicle hood

12 and frame 14, the invention is not so limited. It is to be appreciated that the hinge assembly 10 could equally be provided with either the hood 12 or frame 14 functioning as the equivalent to a hinge arm, and/or if applicable, with a guide slot 30 or a corresponding guide groove or member provided therein.

Although Figure 1 illustrates the vehicle 8 as employing a pair of integrated hinge assemblies 10, it is to be appreciated that the invention is not so limited. In an alternate construction, the vehicle 8 could be provided with only a single hinge assembly 10, with the second other standard hinge being provided to pivotally secure the hood 12 for movement relative to the frame 14.

Although the detailed description describes and illustrates various preferred embodiments, the invention is not so limited. Many modifications and variations will now occur to persons skilled in the art. For a definition of the invention, reference may be had to the appended claims.