EP0000277B1

EP0000277B1 - Hinge assembly and vehicle including same

Info

Publication number: EP0000277B1
Application number: EP78300085A
Authority: EP
Inventors: Elmer William Silaghi
Original assignee: Massey Ferguson Inc
Current assignee: Massey Ferguson Inc
Priority date: 1977-06-29
Filing date: 1978-06-27
Publication date: 1981-04-29
Also published as: IT7824928A0; ES471242A1; DE2860641D1; IT1096031B; CA1084555A; BR7803961A; EP0000277A1; US4134179A

Description

Technical Field

This invention relates to hinge assemblies and more particularly to assemblies for use with the hoods of vehicle engine compartments.

Background Art

On some vehicles such as large tractors and off-the-road equipment hoods over the engine compartment become extremely large and heavy and difficult to open manually. Various forms of spring-assisted hinge arrangements have been employed for use on vehicles. U.S. Patent 3388417 discloses one such form of hinge. Generally such hinges have not been efficient in use since they utilize linkages which are difficult to install and maintain in operative condition and which have high frictional losses.

Disclosure of Invention

It is an object of the present invention to provide an improved form of hinge assembly for mounting a vehicle engine compartment hood.
According to the present invention there is provided a hinge assembly for a vehicle having an engine compartment with a hood opening and a hood for closing the opening, the hinge assembly including hinge members connected to the hood and the engine compartment respectively, said members being pivotally connected to each other for swinging movement of the hood about a first horizontal axis from a closed to an open position, cam means fixed relative to the compartment hinge member and to the first axis, a force-transmitting member mounted for pivoting relative to the hood about a second axis spaced from the first axis, cam follower means for engagement with the cam means and carried by the force-transmitting member (40), and spring means arranged to apply a pivoting force to the force-transmitting member to assist opening of the hood, the hinge assembly being characterised in that the spring means is carried by the hood, in that the cam follower means is maintained in contact with the cam means during pivotting of the hood solely by the spring means, and in that the cam means has a curved surface for contact by the cam follower means, the cam surface being shaped so that the distance of the point of contact of the follower means from the first axis varies as the hood swings about the first axis in such a manner that during opening of the hood the spring means applies a swinging force to the hood in opposition to the weight of the hood such that a substantially constant manual effort is required to swing the hood through a substantial part of said swing movement towards the open position.
The pivoting force of the spring means is preferably sufficient to move the hood to a partially open position without requiring any manual effort.
The hood may swing upwardly and through a vertical position on its way to its open position, the spring means being arranged to provide assistance in the upward swinging of the hood and to oppose the movement of the hood towards this open position after it has passed through the vertical position.
The invention also provides a vehicle with an engine compartment hood mounted on a hinge assembly of the form described above, said vehicle also including a releasable latch assembly for holding the hood in its closed position, the hood being arranged to swing to the partially open position on release of the latch assembly.
In order to provide a clean appearance the hinge assembly is preferably concealed within the engine compartment when the hood is in its closed position.

Brief Description of Drawings

One embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a side elevation of a vehicle with a hinged engine compartment hood;
Figure 2 is a side elevation of a hinge assembly in accordance with the invention used to mount the hood of Figure 1 and viewed from within the engine compartment;
Figure 3 is an end view of the hinge assembly seen in Figure 2 looking rearwardly of the vehicle;
Figure 4 is a side elevation similar to Figure 2 but at an enlarged scale and showing the hood in a partially open position;
Figure 5 is a view similar to Figure 4 showing the hood in a fully opened position, and
Figure 6 is a side elevation of the hood latch assembly used to maintain the hood in a closed position.

Best Mode of Carrying Out Invention

Referring to the drawings, the hinge assembly of the present invention is designated at 10 and is used to support a hood 12 closing the opening 14 giving access to an engine compartment 15 of a vehicle 16. The forward end of the opening 14 is defined by cowl 17 extending over and rearwardly from a grill 18.
A pair of the hinge assemblies 10 are used to suuport the hood 12 for movement from the closed position relative to the opening 14 of the engine compartment 15 as seen in Figure 2 to the open position seen in full line in Figure 1 and also in Figure 5. Opening and closing movement of the hood is about a horizontal hinge axis formed by a pin indicated at 22. Each of the pair of hinge assemblies 10 includes a hood hinge member or subassembly 24 and an engine compartment hinge member or subassembly 26 which are connected together by pin 22. The hinge assemblies 10 are identical with each other and only one will be referred to hereafter.
The hood hinge member 24 includes a pair of spaced C-shaped arm members 28 formed rigidly with a base member 30 which serves to maintain the arm members 28 in fixed, spaced-apart relationship to each other. The base member 30 extends generally longitudinally of the hood 12 and is adapted to be bolted to the latter. The forward ends of the arm members 28 pivotally receive the pin 22 which defines the horizontal hinge axis. The pin 22 is supported by a U-shaped bracket member 34 which is bolted or otherwise fastened to the cowl 17 of the engine compartment 10. The U-shaped bracket has a cam member 36 in the form of a plate extending generally longitudinally of the engine compartment at the underside of the cowl 17.
The spaced arm members 28 support a force-transmitting member which is in the form of a pair of parallel bell cranks 40 beld in fixed, spaced-apart relationship on opposite ends of a tubular member 42. A pin 44 passes through the tubular member 42 and opposite ends of this pin are held in bosses 46 supported in axially aligned relationship on the inboard sides of the arm members 28. One arm 48 of each of the bell cranks 40 is provided with a boss 50 which supports the opposite ends of a pin 52. The pin 52 rotatably supports a cam follower in the form of a roller 54 which engages a cam surface 56 on the edge of the cam member 36.
The roller 54 is urged into engagement with the cam surface 56 by a pair of tension springs 58. One end of each spring 58 is connected to the free end of one of the arms 60 of each bell crank 40 and ther other end of each spring is anchored to the base member 30. The springs 58 tend to rotate the bell cranks 40 about the pin 44 to urge the roller 54 into engagement with the cam surface 56.
The cam surface 56 is shaped so that as the roller 54 moves along the surface 56 the distance between the pin 44 and the surface 56 increases. Thus there is a tendency for the hood 12 to be urged upwardly under the influence of the springs 58 so that the bell cranks 40 can rotate in a clockwise sense under the action of the springs 58, this clockwise rotation of the bell cranks 40 being permitted by the increasing distance between the pin 44 and surface 50.
The hood is maintained in its closed position by a latch assembly 64 including a latch member 66 pivoted relative to the hood 12 for movement about a latch pin 68. The lower end of the latch member 66 is provided with a recess 70 adapted to engage a lock pin 72 held in fixed relationship relative to the engine compartment 15. The latch member 66 is urged to a latched position in which the recess 70 receives the lock pin 72 by a spring 73 one end of which is anchored to the underside of hood 12 and the other end to the latch member 66 so that the latter is urged in a clockwise direction as viewed in Figure 6. The lower end of the latch member 66 is provided with a beveled or cam surface 74 which acts to engage the pin 72 and moves the latch member 66 in a clockwise direction during closing movement of the hood 12.
To release the latch assembly 64 the latch member 66 is rotated in a counterclockwise direction against the force of the spring 73 by exerting a manual force on the pad 76 located at the rearward edge of the hood 12. This moves the recess 70 of latch member 66 out of engagement with lock pin 72 to permit the springs 58 to rotate the bell cranks 40 in a clockwise direction as viewed in Figure 2 relative to the arm members 28 and cause the hood 12 to move to an ajar or slightly open position as illustrated in dash lines in Figure 1 or as shown in Figure 4.
Such movement is accomplished without the requirement for any additional physical effort on the part of a person opening the hood. Thereafter the hood 12 may be pivoted about its horizontal hinge axis 22 by the use of a small effort during which the hood 12 may be pivoted from its partially open position through a generally vertical position to a position at an angle where the hood rests against stops to prevent further rotation.
In actual practice the initial opening of the hood without the assistance of any physical effort is for the first twenty degrees of movement after which the hood may be rotated through an arc of approximately an additional 120 degrees to its fully open position.
The profile of the cam surface 56 is arranged to be such that a varying force is applied to the hood 12 which is generally proportional to the effort required to move the hood through its arcuate path. It will understood, for example, that if the movement of the hood were not assisted, the effort required to open the hood would be large initially and decrease as the hood approached a generally vertical position in which its mass is in vertical balance. Movement beyond the vertically balanced position is assisted by the force of gravity until the hood reaches its fully open position seen in Figure 5. The springs 58 apply the roller 54 against the cam surface 56 and the profile of the cam surface 56 is such that a force is applied to the hood which is proportional to the effort that would otherwise be required to open the hood. Thus after the initial opening movement of the hood to the Figure 4 position under the effort of the springs alone, the hood 12 can be moved through its remaining arcuate path by applying a relatively uniform physical effort which in actual practice is maintained at a minimum. As the hood 12 moves beyond the vertically balanced position to the position seen in Figure 5 the springs 58 act to resist opening movement to counteract the gravitation effect tending to open the hood. As the hood approaches the fully open position shown in Figure 5 the roller 54 is arranged to contact the underside of the cowl 17 thus limiting further movement of the hood.
It will be noted that the entire hinge assembly is concealed within the engine compartment and that the hinge or horizontal axis 22 is disposed beneath the cowl 17 and somewhat forwardly of the forward edge of the hood 12. The assembly 10 can be installed as a unit or the hood hinge subassembly 24 and compartment hinge subassembly 26 may be installed separately with the subsequent insertion of the hinge pin 22 since all of the components of the assembly 20 are mounted on either of the subassemblies without additional attachments for linkages or the like.

Claims

1. A hinge assembly (10) for a vehicle (16) having an engine compartment (15) with a hood opening and a hood (12) for closing the opening, the hinge assembly ancluding hinge members (24, 26) connected to the hood and the engine compartment respectively said members being pivotally connected to each other for swinging movement of the hood about a first horizontal axis (22) from a closed to an open position, cam means (36) fixed relative to the compartment hinge member (26) and to the first axis, a force-transmitting member (40) carried by and mounted for pivotting relative to the hood (12) abaout a second axis (44) spaced from the first axis (22), cam follower means (54) for engagement with the cam means (36) and carried by the force-transmitting member (40), and spring means (58) arranged to apply a pivoting force to the force-transmitting member (40) to assist opening of the hood, the hinge assembly being characterised in that the spring means (58) is carried by the hood (12), in that the cam follower means (54) is maintained in contact with the cam means (36) during pivotting of the hood solely by the spring means (58), and in that the cam means (36) has a curved cam surface (56) for contact by the cam follower means (54), the cam surface being shaped so that the distance of the point of contact of the follower means from the first axis (22) varies as the hood (12) swings about the first axis (22) in such a manner that during opening of the hood (12) the spring means (58) applies a swinging force to the hood (12) in opposition to the weight of the hood (12) such that a substantially constant manual effort is required to swing the hood (12) through a substantial part of said swinging movement towards the open position.

2. A hinge assembly according to claim 1 characterised in that the pivoting force of the spring means (58) is sufficient to move the hood (12) to a partially open position without required any manual effort.

3. A hinge assembly according to claim 1 or claim 2 characterised in that the hood (12) swings upwardly and through a vertical position on its way to its open position, the spring means (58) being arranged to provide assistance in the upward swinging of the hood and to oppose the movement of the hood towards its open position after it has passed through the vertical position.

4. A hinge assembly according to any one of claims 1 to 3 characterised in that the cam follower means comprises a member (54) rotatably mounted on the force-transmitting member (40) for rolling contact with the cam means (36,56).

5. A hinge assembly according to any one of claims 1 to 4 characterised in that the force-transmitting member (40) is pivotally mounted on the hood hinge member (24).

6. A vehicle (16) with an engine compartment hood (12) said vehicle being characterised in that the hood is mounted on a hinge assembly (10) according to claim 2 and in that a releasable latch assembly (64) is also provided for holding the hood in its closed position, the hood being arranged to swing to the partially open position on release of the latch assembly.

7. A vehicle (16) according to claim 6 characterised in that the hinge assembly (10) is concealed within the engine compartment (15) when the hood (12) is in its closed position.