EP3265632B1

EP3265632B1 - Auxiliary hood lock structure

Info

Publication number: EP3265632B1
Application number: EP15707370.1A
Authority: EP
Inventors: Pradeep BANSOD
Original assignee: Toyota Motor Europe NV SA
Current assignee: Toyota Motor Europe NV SA
Priority date: 2015-03-02
Filing date: 2015-03-02
Publication date: 2022-04-20
Anticipated expiration: 2035-03-02
Also published as: WO2016138932A1; EP3265632A1

Description

Field of the Disclosure

The present disclosure is related to passive devices for improving motor vehicle/pedestrian impact safety, and more particularly to an auxiliary hood lock structure configured to reduce leg injuries during pedestrian impacts.

Background of the Disclosure

Automobiles typically include a main hood locking mechanism that acts to hold a hood covering a front of the vehicle in a closed position. Such a hood lock is often released via an actuator present in the passenger cabin of the automobile. Once the main hood lock is released, the hood is free to open partially, at which point an auxiliary hood lock prevents the hood from fully opening.
Typical auxiliary hood locks act as a safety mechanism to prevent the hood from fully opening should the main hood lock be actuated from the cabin unintentionally while the vehicle is underway. Fig. 1 shows an exemplary auxiliary hood lock known in the prior art. Such auxiliary hood locks include a lever 3 and a hook 1, the hook being configured to engage a catch attached to a chassis of the vehicle to prevent the hood from fully opening. Lever 3 enables a user to, after release of a main hood lock, to release the auxiliary hood lock by, for example, lifting up on lever 3, thereby disengaging hook 1 from the catch and allowing the hood to fully open.
Vehicle safety ratings are an important factor in the design of a vehicle and can have significant impact with regard to governmental approval and decision making by purchasers of vehicles, among others.
When the front end of a vehicle contacts the lower extremities of a pedestrian, the legs can be rapidly accelerated up to the speed of the vehicle while the head and torso of the pedestrian remain relatively still. As the vehicle continues to move forward, the lower extremities begin to wrap around the contour of the front end of the vehicle and portions of the vehicle in contact with the pedestrian may continue to exert force upon the pedestrian based the speed of the vehicle and the amount of impact energy dissipated by the vehicle itself through deformation of components (e.g., bumper, hood, auxiliary hood lock lever, etc.)
In the past, car manufacturers have installed pedestrian protection airbags or active hood systems to enhance the pedestrian protection features. Such active systems can be costly and difficult to design/construct.
In addition to active systems, passive designs have also been implemented. However, while such passive systems are less expensive, there is a desire to continually to improve such systems so as to reduce the possibility of injury.
EP 2 615 012 discloses an auxiliary hood lock structure that, while ensuring operability of an auxiliary lever, allows a deformation stroke of a front end portion of a hood large when a collision body collides with the hood from a front-most end side thereof. An upper portion side of a hood catch and an auxiliary lever are connected by a connecting structure so as to be able to rotate and be displaced integrally around an axis of a first pin that is in a hood transverse direction. Further, when load of a predetermined value or more toward a vehicle rear lower side is inputted to the auxiliary lever in a closed state of the hood, relative rotational displacement, around an axis of a second pin that is in the hood transverse direction, of the auxiliary lever with respect to the hood catch due to input of the load is permitted by the connecting structure.
JP 2010-163767 discloses a lever portion of an auxiliary lever including an overhang portion overhanging forward from a plane including a hook portion, a rising portion which rises upward from a front end of the overhang portion, and an operation portion, which is elongated at an angle of inclination directed upward with respect to a horizontal direction, forward from an upper end of the rising portion.
US 6,543,822 discloses a self-presenting secondary hood latch assembly.

SUMMARY OF THE DISCLOSURE

Currently, it remains desirable to provide vehicle structures capable of reducing impact forces with the goal of reducing injury to pedestrians during collision with a vehicle.
It has been determined that prior systems, while providing some level of pedestrian protection, may still be improved. For example, the weakened lever of JP 2010-163767 may fail as a result of general use (e.g., due to fatigue), and such a part is generally not reusable following an impact.
Further, designs associated with EP 2 615 012 may result in crash results that are unsatisfactory (e.g., undesirable levels of injury to a pedestrian), vibration during normal operation, and such designs are generally not reusable after impact (e.g., a pedestrian crash).
Therefore, according to the invention, an auxiliary hood lock for a holding a vehicle hood in a closed position is provided as defined in claim 1.
By providing such a configuration, a force to displace the lever means can be designed based on a resilient means to be and can therefore be configured to a minimum force to counter resulting rattle under normal operating conditions. Further, force variation to displace the lever means can be kept to minimum as the first and second resilient members (e.g., springs) are easy to manufacture without no special effort, and tight tolerances can be achieved. Moreover, after lever is displaced (e.g., as a result of a pedestrian impact) it can return to its original position and the auxiliary hood lock can be reused.
[CANCELLED]
The second resilient means and at least a portion of the lever means may be horizontally offset from the catch engagement means.
[CANCELLED]
The biasing force may be configured such that a force required to move the lever means in a direction opposite to the release direction ranges from 0.5 to 40 Newtons (N), better 10 to 39 N, and still better 20 to 36N, as measured from an at-rest position.
The biasing force may be configured such that a force to operate the lever in the release direction may range from 0.3N to 21N, better between 20 and 21N, as measured from an at-rest position.
An axis of rotation of the catch engagement means and the lever means may be concentric.
An axis of rotation of the first resilient means and the second resilient means may be concentric.
The axis of rotation as mentioned above, may be shared among each of the catch engagement means, the lever means, the first resilient means, and the second resilient means.
The engaging portion may be unitarily formed with the lever means.
The first resilient means and the second resilient means may include coil springs.
The engaging portion may include a protrusion and the lever interface may include a hole (e.g., an elongate hole) in the catch engaging means.
According to further embodiments of the present invention, a vehicle comprising the auxiliary hood lock according to any of the previously described aspects may be provided.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as defined by appended claims.
The accompanying drawings constitute a part of this specification, illustrate embodiments of the disclosure and together with the description, serve to explain the principles thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows an exemplary auxiliary hood lock known in the art;
Fig. 2 shows an exemplary auxiliary hood lock according to embodiments of the present disclosure in an assembled condition;
Fig. 3 shows an exploded view of the auxiliary hood lock of Fig. 2;
Figs. 4A and 4B shows exemplary modes of operation including a range of motion of the auxiliary hood lock according to embodiments of the present disclosure;
Fig. 5 is a schematic showing features before and after a theoretical impact on a front portion of a vehicle including the auxiliary hood lock according to embodiments of the present disclosure;
Fig. 6 is a graph showing a biasing force based on an angular position of a lever of an exemplary auxiliary hood lock;
Fig. 7 is a graph showing a moment and spring stress based on a displacement angle of a lever of an exemplary hood lock.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to exemplary embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
Fig. 1 shows an exemplary prior art auxiliary hood lock, including a catch, a hook and lever, and a spring biasing the hook toward the catch to maintain a locked position, among others.
Fig. 2 shows an exemplary auxiliary hood lock according to embodiments of the present disclosure in an assembled condition, while Fig. 3 shows an exploded view of the auxiliary hood lock of Fig. 2 for additional detail. The auxiliary hood lock may be configured to engage a latch 10 in order to maintain a hood 115 in a closed position until actuation of the auxiliary hood lock to disengage the latch 10 and allow opening of the hood 115. The auxiliary hood lock may include a hook 1, a lever 3, a first resilient member 7, and a second resilient member 8, among others (e.g., a mounting bracket 4, a pin 2, various bushings 5 and 6, etc.)
Mounting bracket 4 may be configured to enable mounting of the auxiliary hood lock to a hood 115 of the vehicle as well as providing an anchoring element for the operable components of the auxiliary hood lock (e.g., hook 1 and lever 3). Therefore mounting bracket 4 may include one or more mounting points 130 (e.g., through holes) configured to receive a fastener (e.g., bolt, screw, rivet, etc.) for affixing the auxiliary hood lock to hood 115.
Mounting bracket 4 may also include two or more pin receiving holes 135 located opposite mounting points 130 configured to receive a pin or shaft 2 about which hook 1 and lever 3 (among others) may rotate. In other words, receiving holes 135 may act as a hinge point forming a common axis of rotation about pin 2 for hook 1 and lever 3.
Hook 1 may be configured to engage a catch 10 attached to a chassis (not shown) of the vehicle, and may therefore, be of any suitable shape and material for performing such an engagement. For example, hook 1 may be generally elongate with a recess or through-hole positioned at a location configured to cause engagement with latch 10 when the auxiliary hood lock is in the closed position (as shown by the solid portion of Fig. 4A). The closed position of auxiliary hood lock will be understood to mean an at-rest position of the auxiliary hood lock with hood 115 fully closed or partially open following actuation of the hood lock.
Hook 1 may be fabricated from metal (e.g., steel, aluminum, etc), plastic (e.g., ABS, polyethylene, etc.) a combination thereof (e.g., overmolded metal) and/or any other suitable materials. For example, hook 1 may be formed by stamping, cutting, and/or machining of steel. Hook 1 may also be formed via a molding process using plastic. Notably, hook 1 is formed separately from lever 3, which will be described in greater detail below, such that hook 1 and lever 3 comprise individual and distinct parts.
Hook 1 may be configured to pivot about an axis of rotation at a proximal end of hook 1. For example, hook 1 may include a plurality of holes aligned axially at the proximal end of hook 1, such holes being configured to receive a pin or shaft 2 about which hook 1 may rotate toward or away from latch 10 as shown at Fig. 4A.
Hook 1 may include a lever interface 30, permitting an operable engagement with a hook interface 35 present on lever 3, which will be described in greater detail below. Lever interface 30 may comprise a hole (e.g., an elongate, arcuate hole) in a portion of hook 1, for example, on a side portion of hook 1.
Lever interface 30 may extend over a intended stroke angle α of lever 3 in a direction R_o opposite to the release direction R. In other words, lever interface 30 may be an arcuate shaped hole extending over a stroke angle α as shown at Figure 4B, which may enable a range of motion of hook interface 35 from an engaged position with hook 1 via lever interface 30 to a full stroke position opposite the engaged position. Stroke angle α may be suitably configured such that a sufficient range of motion is provided to lever interface 30 in a direction R_o opposite the release direction R to prevent exertion of a force on hook 1 by lever 3 in the event of an impact. This can thereby reduce the likelihood of damage to the auxiliary hood lock by allowing motion instead of deformation. According to some embodiments, total stroke angle α may range between 10 and 90 degrees, or even between 20 and 40 degrees from an at-rest position of lever 3.
A first resilient member 7 may be configured to bias hook 1 toward the engaged position with latch 10. First resilient member 7 may comprise a spring (e.g., a coil spring, a band spring, torsion type spring, etc.), a piece of elastic material (e.g., a rubber piece), or other suitable resilient element. For example, a torsional type coil spring may implemented as resilient member 7 and may be configured to exert a torsional force (i.e., a moment) about the common axis of rotation X. Therefore, first resilient member 7 may be positioned between receiving holes 135 such that pin 2 is inserted through the eye of the torsional type coil spring, for example.
The torsional force exerted by the torsional type coil spring may act on a first point associated with mounting bracket 4 and a second point associated with hook 1 such that hook 1 is rotationally biased toward latch 10. The torsional force exerted by first resilient member 7 may range between 1.5 to approximately 10N, and according to some embodiments, even higher than 10N (e.g., 15N, 20N, etc.). In this way, hook 1 may maintain engagement with latch 10 during periods of operation of the vehicle without causing rattling (e.g., when hitting bumps) but may still be disengaged when lever 3 is moved in a release direction by a user wishing to open hood 115 without the exertion of excessive force that may cause discomfort to the user.
Lever 3 may be configured to enable operation from an outside of the vehicle for purposes of disengaging hook 1 from latch 10 to enable opening of hood 115. Therefore, lever 3 may include a user interface 300, a lever arm 310, connecting arms 320, a spring interface 200, pivot points 210, and a hook interface 35. Lever 3 and its components may be formed unitarily (i.e., as one single piece) from any suitable material (e.g., metal, plastic, combinations thereof, etc.), and may fabricated by processes similar to those described above with regard to hook 1 (e.g., machining, stamping, molding, cutting, etc.)
User interface 300 may be configured to enable actuation of lever 3 by a user from outside the vehicle. Therefore, user interface 300 may be formed unitarily with lever 3 and may be shaped to provide a surface on which a user may exert a force F in a release direction R of lever 3 as shown at Fig. 4A. User interface 300 may be shaped as a tab or other shape providing adequate surface area for a user to comfortably exert a force in the release direction R on lever 3. One of skill will recognize that various shapes may be implemented without departing from the scope of the present disclosure.
Lever arm 310 of lever 3 may be configured to provide a desirable amount of leverage based on an intended user force for moving lever 3 in the release direction R against a biasing force of first resilient member 7, while also taking into account any biasing force in the release direction R provided by second resilient member 8. In addition, based on criteria such as location of auxiliary hood lock on the vehicle and the location of a hood lock housing in a radiator cover of the vehicle, certain offsets O_s and O_L may be provided between connection points of lever arm 310 within connecting arms 320 in order to place user interface 300 in the desired location. Such offsets may also be useful for accommodating, for example, second resilient member 8 between connecting arms 320, as will be described below.
Hook interface 35 of lever 3 may be configured to operably engage lever interface 30 such that lever 3 may exert a force F on hook 1 in release direction R over an angular distance of Θ degrees, which may range from 10 to 20 degrees from an at-rest position of lever 3. Therefore, hook interface 35 may be formed integrally with lever 3 and may comprise a protrusion extending away from lever 3, such that, in an assembled condition, hook interface 35 extends at least partially through lever interface 30 of hook 1. In so doing, upon application of a force in the release direction R, as shown at Fig. 4A, hook interface 35 may transfer the force F to hook 1 causing a corresponding rotation of hook 1 about axis X, and disengagement of hook 1 from latch 10.
Pivot points 210 of lever 3 may be integrally formed with lever 3 and may permit insertion of pin 2 therethrough, such that the common axis of rotation X is shared by hook 1 and lever 3, among others. Pivot points 210 may therefore comprise one or more hinge holes at a proximal ends of connecting arms 320 of lever 3. The hinge holes may be of sufficient size to accept pin 2, but with a clearance configured to prevent rattle during normal operation of the vehicle.
Spring interface 200 of lever 3 may be configured to engage with at least a portion of second resilient member 8, enabling transfer of a force exerted by second resilient member 8 to lever 3. For example, spring interface 200 may include a U-shaped protrusion or other suitable shape enabling a portion of second resilient member 8 to exert a force on spring interface 200. Spring interface 200 may be formed integrally with lever 3 in a similar fashion to hook interface 35, for example, by a stamping operation.
Second resilient member 8 may be configured to bias lever 3 toward a release direction R of the auxiliary hood lock. Second resilient member 8 may be similar to first resilient member 7 in that it may comprise a spring (e.g., a coil spring, a band spring, torsion type spring, etc.), a piece of elastic material (e.g., a rubber piece), or other suitable resilient element. According to some embodiments of the invention, second resilient member 8 may comprise a torsional type coil spring.
Second resilient member 8 may be mounted between connecting arms 320 of lever 3 such that pin 2 may be inserted through pivot points 210 and an eye of second resilient member 8. In this way, first and second resilient member (as well as lever 3 and hook 1) may share the same axis of rotation X.
A biasing force of the second resilient member is configured such that the hook interface remains in contact with a portion of the lever interface during normal operation of the vehicle. Second resilient member 8 may therefore, engage with spring interface 200 of lever 3 such that a torsional force may bias a rotation of lever 3 about axis X so as to cause hook interface 35 to remain in contact with hook 1 during normal operation of vehicle 1.
By providing a second resilient member 8 having a biasing force of at least about 0.5N toward the release direction R, hook interface 35 may maintain contact with hook 1 within lever interface 30 during normal operation of the vehicle, and rattling may be prevented. However, to prevent users from attempting to operate lever 3 by exerting force in a direction opposition to a release direction R_o, it has been determined that a minimum biasing force for second resilient member 8 could be more optimally set at greater than 10N (e.g., between 10 and 55N). Such a biasing force may provide adequate feedback to a user that operation in a direction opposite to the release direction R_o is not intended, while still preventing rattle during normal operation.
Second resilient member 8 is further configured to absorb energy during an impact of vehicle with, for example, a pedestrian.
Fig. 5 is a schematic showing features before and after a theoretical impact on a front portion of a vehicle including the auxiliary hood lock according to embodiments of the present disclosure. As shown by the dashed lines, a vehicle bumper 100, grill 110, and hood 115 are in normal position with hood 115 closed, and hook 1 engaged with latch 10. Lever 3 may be operated by a user in a release direction R to release hook 1 from latch 10 and open hood 115.
Following an impact, as shown at Fig. 5 by the solid lines, bumper 100', grill 110', and hood 115' have all been displaced as a result of the impact force. In addition, the impact force has been at least partially exerted upon lever 3 in a direction R_o opposite to the release direction R, thereby causing movement of lever 3 about pin 2, over at least a portion of stroke angle a. During the impact, second resilient member 8 resists movement of a force up to its predetermined biasing force, and thereafter, allows movement of lever 3 throughout stroke angle α as long as the force of impact continues to exceed the biasing force of second resilient member 8. Such a configuration prevents damage to the auxiliary hood lock (e.g., lever 3 and hook 1) by allowing for movement instead of deformation, while providing a gradual resistance increase to the motion. This allows auxiliary hood lock to be reused rather than replaced following an impact.
One of skill in the art will recognize that the biasing force of second resilient member 8 may be adjusted based on a desired impact energy absorption, stroke angle, etc. so as to meet particular design criteria, for example, crash impact standards set forth by governing bodies.
Throughout the description, including the claims, the term "comprising a" should be understood as being synonymous with "comprising at least one" unless otherwise stated. In addition, any range set forth in the description, including the claims should be understood as including its end value(s) unless otherwise stated. Specific values for described elements should be understood to be within accepted manufacturing or industry tolerances known to one of skill in the art, and any use of the terms "substantially" and/or "approximately" and/or "generally" should be understood to mean falling within such accepted tolerances.
Where any standards of national, international, or other standards body are referenced (e.g., ISO, etc.), such references are intended to refer to the standard as defined by the national or international standards body as of the priority date of the present specification. Any subsequent substantive changes to such standards are not intended to modify the scope and/or definitions of the present disclosure and/or claims.
Although the present disclosure herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention.
It is intended that the specification and examples be considered as exemplary only, the invention being defined by the following claims.

Claims

An auxiliary hood lock for a holding a vehicle hood in a closed position, reducing injury to a pedestrian, and/or damage to the hood lock during a collision, comprising:
catch engagement means (1) comprising a lever interface portion (30), the catch engaging means (1) being configured to engage a catch (10) attached to a chassis of the vehicle;

lever means (3) comprising an engaging portion (35) configured to operably engage the catch engagement means (1) at the lever interface portion (30);

first resilient means (7) configured to bias the catch engagement means (1) toward an engaged position with the catch (10); and

second resilient means (8) configured to bias the lever means (3) toward a release direction (R) of the auxiliary hood lock, wherein the lever interface portion (30) is configured to enable the engaging portion (35) to move from a normal position with the vehicle hood in the closed position in a direction (Ro) opposite to the release direction (R) without exerting a force on the catch engagement means (1), wherein the biasing force of the second resilient means (8) is configured such that the engaging portion (35) remains in contact with a portion of the lever interface portion (30) during normal operation of the vehicle, characterised in that the second resilient means (8) is further configured to absorb energy during an impact on the hood lock in the direction (Ro) opposite to the release direction (R).
The auxiliary hood lock according to any of the previous claims, wherein the second resilient means (8) and at least a portion of the lever means (3) are horizontally offset from the catch engagement means (1).
The auxiliary hood lock according to claim 2, wherein the biasing force is configured such that a force required to move the lever means (3) in a direction opposite to the release direction ranges between 0.5 to 40N from an at-rest position.
The auxiliary hood lock according to any of the preceding claims wherein an axis of rotation (X) of the catch engagement means (1) and the lever means (3) are concentric.
The auxiliary hood lock according to any of the preceding claims, wherein an axis of rotation (X) of the first resilient means (7) and the second resilient means (8) are concentric.
The auxiliary hood lock according to any of claims 4 and 5, wherein the axis of rotation (X) is shared among each of the catch engagement means (1), the lever means (3), the first resilient means (7), and the second resilient means (8).
The auxiliary hood lock according to any of the preceding claims, wherein the engaging portion (35) is unitarily formed with the lever means (3).
The auxiliary hood lock according to any of the preceding claims, wherein the engaging portion (35) is a hook interface (35) and comprises a protrusion extending away from the lever means (3), such that, in an assembled condition, the hook interface (35) extends at least partially through the lever interface portion (30) of a hook (1) forming the catch engagement means (1).
The auxiliary hood lock according to any of the preceding claims, wherein, the lever interface portion (30) comprises a hole, for example, an elongate or arcuate hole in a portion of the hook interface (1), for example, on a side portion of the hook interface (1).
A vehicle comprising the auxiliary hood lock according to any of the previous claims.