[0001] The present invention relates to a latch for automotive vehicle with improved claw
stroke.
[0002] A latch for a motor vehicle door usually comprises a housing in which a claw is pivotally
mounted between different functional angular positions. In the closed position of
the door, the claw cooperates with a striker carried by a vehicle body, for example
a pillar of the vehicle body.
[0003] For safety reasons, it is important, when a vehicle is in motion, that each vehicle
door can be held in the closed position with no risk of accidental opening, particularly
in the event of a vehicle accident or strong vehicle vibrations.
[0004] The quality of the cooperation between the strike and the claw is therefore essential
to ensure that a vehicle door is held securely in the closed position both in normal
conditions of use of the vehicle and in exceptional conditions of use of the vehicle.
[0005] However, the operating conditions of an automotive vehicle door latch must be adapted
to certain temporary or exceptional circumstances of use subjecting the lock to particular
constraints.
[0006] Such particular constraints are observed in particular during the closing of the
door. Indeed, in this case, the kinetic energy of the door which is moved towards
its closed position will be dissipated in the elements of the door and the vehicle
body, in particular the latch of the door and the seals carried by the vehicle body
and the door. Frictional forces between different elements of the latch and the vehicle
body also dissipate the kinetic energy of the door. In addition, the latch usually
comprises elastic masses which contribute significantly to the dissipation of the
kinetic energy of the door.
[0007] The control of the dissipation of kinetic energy of a door moved towards its closed
position must be done in particular in good conditions of limitation of wear of the
latch and comfort for the user, that is to say without causing shocks and undesirable
noises. In particular, the latch must satisfy these conditions while allowing a relatively
unavoidable overtravel of the claw when closing the door, this overtravel having to
be able to be completed without strong resistance from the claw to avoid causing a
shock or an undesirable noise of the claw against the striker.
[0008] As the precision of the relative position of a latch and a striker is essential for
the correct operating of a vehicle door latch, it has been proposed in the state of
the art, in particular in
EP 4 219 872 A1, means which make it possible to precisely adjust the relative position of a latch
and a striker when the door is closed specifically for this adjustment operation.
[0009] When the door is closed for adjustment and before the striker pad is finally fixed
to the vehicle body, the means disclosed in
EP 4 219 872 A1 allow a relative movement of the striker pad by cooperation with the claw. This relative
movement enables the striker to be placed in an optimised position for cooperation
with the claw.
[0010] For this adjustment to be effective, the claw must offer some resistance to the striker.
This means that, unlike when the door is normally closed, the claw must be able to
overtravel when the door is closed in order to adjust the striker position while offering
relative resistance to the striker.
[0011] It is therefore observed that, when closing the door, in certain relatively usual
operating circumstances of the latch, the claw should be able to complete an overtravel
without strong resistance from the claw, in particular to avoid causing an impact
or an undesirable noise of the claw against the striker, whereas in other, more exceptional
operating circumstances of this latch, the claw should be able to complete this overtravel
by opposing a relative resistance to the striker.
[0012] The aim of the invention is in particular to offer a latch for an automotive vehicle
door which, depending on the operating circumstances of the latch, allows the claw
to be over-travelled, sometimes with less resistance and sometimes with greater resistance.
[0013] To that end, the invention relates to a latch for an automotive vehicle door of the
type comprising a housing in which a claw is pivotally mounted between different functional
angular positions including a predetermined exceptional overtravel position,
characterized in that it comprises an elastic abutment deformable between a rest position and a retracted
position, the claw being intended to cooperate with the elastic abutment, against
an elastic return force of this elastic abutment, so as to place the elastic abutment
in the retracted position when the claw reaches its predetermined exceptional overtravel
position.
[0014] Thus, as long as the elastic abutment is not retracted and the claw is in operating
circumstances of the latch causing the claw to cooperate with the elastic abutment,
the claw will be able to complete an overtravel by opposing a relative resistance
to a striker, proportional to the stiffness of the elastic abutment. These operating
circumstances of the latch may correspond, for example, to circumstances of adjustment
of the relative position of a striker intended to cooperate with the claw.
[0015] Furthermore, when operating circumstances of the latch cause the claw to reach its
predetermined exceptional overtravel position, the elastic abutment will be retracted
and will therefore no longer have any resistance effect to an overtravel of the claw
smaller than the exceptional overtravel. Thus, when closing the door under normal
operating circumstances of the latch, the claw will be able to complete an overtravel
without strong resistance from the claw.
[0016] Other optional features of the invention, which may be taken separately or in combination,
are recited below.
[0017] The elastic abutment is formed by an elastic blade, forming a lever of the third
class, a first end of this elastic blade forming the fulcrum of the lever and a second
end of this elastic blade being intended to oppose the load force of a locking element
intended to retain the elastic abutment in its retracted position.
[0018] It should be recalled that a lever is a simple machine. The way a lever operates
is by an effort applied at a point, which moves a load at another point through a
balance point called the fulcrum. It is the relative position of the effort, the load
and the fulcrum that distinguishes the class of the lever. In a third class lever,
the effort is between the load and the fulcrum.
[0019] Preferably, the elastic blade has a generally curved shape such that its centre of
curvature is opposite the claw with respect to this elastic blade. Such a curved shape
of the elastic blade participates to a spring effect of the elastic blade.
[0020] Preferably, the locking element is carried by an elastically deformable detent arm,
this locking element forming a hard point that can be passed by the second end of
the elastic blade when the claw travels a cooperating stroke with the elastic abutment
between a position in which the elastic abutment is active and its retracted position.
[0021] According to one embodiment, the elastic blade and the detent arm are integral with
the same common member, called the temporary elastic abutment member, arranged in
the housing.
[0022] Preferably, the temporary elastic abutment member comprises a mass forming a shock
or vibration absorber for the latch.
[0023] Preferably, the temporary elastic abutment member is formed from at least one material
selected from a polymer and a metallic material, for example spring steel.
[0024] According to one embodiment, the locking element is integral with an operating surface
intended to be actuated, for example by an operating tool having access to the inside
of the housing, against an elastic return force of the detent arm so as to deactivate
the locking element and release the elastic abutment from its retracted position.
Brief description of the Figures
[0025] The invention will be better understood on reading the following description, which
is given by way of example only and with reference to the attached drawings in which:
- Figure 1 is a perspective view of an automotive vehicle body comprising a striker
intended to cooperate with a latch according to the invention as shown in the following
figures;
- Figure 2 is a front view of a latch according to the invention, for an automotive
vehicle door, showing a housing of this latch, part of which has been removed to allow
visual access to a claw of this latch and to a temporary elastic abutment member,
the claw being in an initial position separated from the striker;
- Figure 3 is a similar view to Figure 2, in which the claw is in a first position of
cooperation with the striker;
- Figure 4 is a similar view to Figure 2, in which the claw is in a second position
of cooperation with the striker, succeeding the first position of the figure 3;
- Figure 5 is a similar view to Figure 2, in which the claw is in a third position of
cooperation with the striker, succeeding the second position of the figure 4;
- Figure 6 is a similar view to Figure 2 showing a first variant of the temporary elastic
abutment member;
- Figure 7 is a front view of a second variant of the temporary elastic abutment member.
Detailed description
[0026] There is shown in Figure 1 an automotive vehicle body, designated by the general
reference 10, comprising a striker 12 known per se. The striker 12 is, for example,
mounted on a pillar of the vehicle body 10.
[0027] According to the example shown in Figure 1, the striker 12 is an adjustable striker,
more precisely an auto-adjustable striker.
[0028] The striker 12 is intended to cooperate with a latch 14, shown in Figures 2-5, mounted
on a door (not shown) of the automotive vehicle.
[0029] Referring to Figures 2 to 5, it can be seen that the latch 14 comprises a housing
16 in which a claw 18 is pivotally mounted. The latch 14 further comprises a pawl
20 pivotally mounted in the housing 16. The pawl 20 is intended to cooperate with
the claw 18 in order to close the claw 18 in a position corresponding to a closed
position of the door.
[0030] The latch 14 further comprises an elastic abutment, formed by an elastic blade 22,
which is deformable between a rest position, as shown in Figures 2 and 3, and a retracted
position, as shown in Figure 5.
[0031] In the example shown in the Figures 2-5, the elastic blade 22 forms a lever of the
third class. A first end 22F of the elastic blade 22 forms the fulcrum of the lever.
In the example shown in the Figures 2-5, the elastic blade 22 has a generally curved
shape such that its centre of curvature is opposite the claw 18 with respect to this
elastic blade 22. Such a curved shape of the elastic blade 22 allows a soft contact
with the claw 18 and participates to a spring effect of the elastic blade 22.
[0032] Furthermore, a locking element 24 is carried by an elastically deformable detent
arm 26.
[0033] In the example shown in the Figures 2-5, the elastic blade 22 and the detent arm
26 are integral with the same common member, called the temporary elastic abutment
member 28, arranged in the housing 16.
[0034] The temporary elastic abutment member 28 is mounted in the housing 16 by means known
in the art, for example snap-fastening or screwing means.
[0035] Preferably, the temporary elastic abutment member 28 comprises a mass 30 forming
a shock or vibration absorber for the latch 14. If need be, such a mass 30 may comprise
EPDM rubber (ethylene propylene diene monomer rubber).
[0036] Also, preferably, the temporary elastic abutment member 28 is formed from at least
one material selected from a polymer and a metallic material, for example spring steel.
[0037] The claw 18 is movable between different functional angular positions. Referring
to Figures 2 to 5, it will be described below different positions of the claw 18 corresponding
to different operating conditions of the latch 14. It is to be noted that in Figures
3-5, the striker 12 is schematized by a cross.
[0038] Figure 2 shows the latch 14 in operating conditions corresponding to circumstances
where the door carrying the latch 14 is open, before adjustment of the relative position
of the striker 12. In such conditions, the claw 18 is in an initial position separated
from the striker 12 and the elastic blade 22 is in its rest position.
[0039] Figures 3 and 4 show the claw 18 cooperating with the striker 12, in operating conditions
corresponding to circumstances where the door carrying the latch 14 is moved from
the open position to a close position. Between the positions shown respectively in
Figure 3 and in Figure 4, the claw 18 cooperates with the elastic blade 22, against
the elastic return force of this elastic blade 22, in order to move it from its rest
position shown in Figure 3 to its retracted position shown in Figure 4. The retracted
position of the elastic blade 22 is reached when the claw 18 reaches a predetermined
exceptional overtravel position.
[0040] Thus, between the positions shown respectively in Figure 3 and in Figure 4, the elastic
blade 22 is in an active position in which the elastic blade 22 cooperates with the
claw 18 in order to oppose a relative resistance to the striker 12, proportional to
the stiffness of the elastic blade 22. This resistance allows to place the auto-adjustable
striker 12 in an optimised position for cooperation with the claw 18.
[0041] However, when the elastic blade 22 is in its retracted position shown in Figure 4,
the elastic blade 22 will no longer have any resistance effect to an overtravel of
the claw 18 shorter than the exceptional overtravel of this claw 18.
[0042] It is to be noted that the elastic blade 22 comprises a second end 22B intended to
oppose the load force of the locking element 24 which, as shown in Figure 4, retains
the elastic blade 22 in its retracted position.
[0043] Thus, the locking element 24 forms a hard point that can be passed by the second
end 22B of the elastic blade 22 when the claw 18 travels a cooperating stroke with
the elastic blade 22 between a position in which the elastic blade 22 is active, such
as the one shown in Figure 3, and its retracted position shown in Figures 4 and 5.
[0044] The predetermined exceptional overtravel position of the claw 18 could be reached
in relatively exceptional operating circumstances of the latch 14, for example when
the door is closed for adjustment of the position of the striker 12.
[0045] However, such operating circumstances for adjustment of the position of the striker
12 may, under certain circumstances, not cause the claw 18 to reach its predetermined
exceptional overtravel position. In this case, when the automotive vehicle is provided
with a cinching mechanism for power operation of the latch to assist a vehicle user
in closing the door, an initial operation of the cinching mechanism will allow the
claw 18 to reach the predetermined exceptional overtravel position.
[0046] Figure 5 shows the claw 18 cooperating with the striker 12 in normal conditions for
holding the -door in its closed position. The elastic blade 22, which is in its retracted
position, will no longer have any resistance effect to an overtravel of the claw 18
shorter than the exceptional overtravel of this claw 18, and, of course, will have
no resistance effect to a normal travel of the claw. In the operating circumstances
of Figure 5, the pawl 20 cooperates with the claw 18 in order to close the claw 18
in its position corresponding to the usual closed position of the door.
[0047] Alternative variants of certain latch components are described below, with reference
to Figures 6 and 7. In these Figures 6 and 7, references identical to those in the
preceding Figures designate elements identical or similar to those in the preceding
Figures.
[0048] Figure 6 shows a first variant of the temporary elastic abutment member 28. In this
variant, the locking element 24 is integral with an operating surface 32 intended
to be actuated against an elastic return force of the detent arm 26 so as to deactivate
the locking element 24 and release the elastic blade 22 from its retracted position.
[0049] Release of the elastic blade 22 may be required in particular following a repair
carried out on the door or the latch 14 requiring the position of the striker 12 to
be adjusted again.
[0050] The operating surface 32 can be actuated against the elastic return force of the
detent arm 26 for example by an operating tool 34 having access to the inside of the
housing, represented by an arrow in Figure 6.
[0051] In order to adjust the stiffness of the elastic blade 22 and/or of the detent arm
26, the dimensions of the mass 30 may be reduced, as shown in the second variant of
the temporary elastic abutment member 28 of Figure 7, or increased. Indeed, modification
of the dimensions of the mass 30 will modify the length, and consequently, the stiffness
of the elastic blade 22 and/or of the detent arm 26.
List of references
[0052]
10: automotive vehicle body
12: striker
14: latch
16: housing
18: claw
20: pawl
22: elastic blade
22A: first end or fulcrum of the elastic blade
22B: second end of the elastic blade
24: locking element
26: detent arm
28: temporary elastic abutment member
30: mass forming a shock or vibration absorber
32: operating surface
34: operating tool
1. Latch (14) for an automotive vehicle door of the type comprising a housing (16) in
which a claw (18) is pivotally mounted between different functional angular positions
including a predetermined exceptional overtravel position, characterized in that it comprises an elastic abutment (22) deformable between a rest position and a retracted
position, the claw (18) being intended to cooperate with the elastic abutment (22),
against an elastic return force of this elastic abutment (22), so as to place the
elastic abutment (22) in the retracted position when the claw (18) reaches its predetermined
exceptional overtravel position.
2. Latch (14) according to claim 1, wherein the elastic abutment is formed by an elastic
blade (22) , forming a lever of the third class, a first end (22A) of this elastic
blade (22) forming the fulcrum of the lever and a second end (22B) of this elastic
blade being intended to oppose the load force of a locking element (24) intended to
retain the elastic abutment (22) in its retracted position.
3. Latch (14) according to claim 2, wherein the elastic blade (22) has a generally curved
shape such that its centre of curvature is opposite the claw (18) with respect to
this elastic blade (22).
4. Latch (14) according to claim 2 or 3, wherein the locking element (24) is carried
by an elastically deformable detent arm (26), this locking element (24) forming a
hard point that can be passed by the second end of the elastic blade (22) when the
claw (18) travels a cooperating stroke with the elastic abutment (22) between a position
in which the elastic abutment (22) is active and its retracted position.
5. Latch (14) according to claim 4, wherein the elastic blade (22) and the detent arm
(26) are integral with the same common member, called the temporary elastic abutment
member (28), arranged in the housing (16).
6. Latch (14) according to claim 5, wherein the temporary elastic abutment member (28)
comprises a mass (30) forming a shock or vibration absorber for the latch (14).
7. Latch (14) according to claim 5 or 6, wherein the temporary elastic abutment member
(28) is formed from at least one material selected from a polymer and a metallic material,
for example spring steel.
8. Latch (14) according to any one of claims 4 to 7, wherein the locking element (24)
is integral with an operating surface (32) intended to be actuated, for example by
an operating tool (34) having access to the inside of the housing (16), against an
elastic return force of the detent arm (26) so as to deactivate the locking element
(24) and release the elastic abutment (28) from its retracted position.