Door latch for closing a door of a motor vehicle

Abstract

A door latch (1) for closing a door of a motor vehicle comprising a claw (2) having a recess (4) to catch a striker (5) in a closed position, the claw (2) being configured to rotate between an open position and a closed position, a pivoting pawl (6) configured to interact with said claw (2) in the closed position to prevent a rotation in open position of said claw (2), wherein the claw (2) comprises an embedded bumper (7) configured to hit an end stop (8) of the door latch (1) when the claw (2) rotates in the closed position.

Description

TECHNICAL FIELD

[0001] The present invention relates to a door latch for closing a door of a motor vehicle, particularly a side door or a trunk lid or similar. The invention also relates to a claw of the door latch and to a manufacturing method of said claw.BACKGROUND OF THE INVENTION

[0002] Door latches are mechanical commodities that allow the door retention on the vehicle body, but also which act during the closure kinematics. When closing a door, an amount of kinetic energy (slamming speed and weight) is dissipated on a very short stroke usually named the closing over-stroke. A part of the energy is absorbed through the door seals, another through friction (hinges) and a main quantity is absorbed by the latch bumpers.

[0003] These latches bumpers help to dissipate energy when the door is closing but also help to immobilize the door on the vehicle body through the striker / claw connection, limiting the micro movements of the door when the vehicle moves. Indeed, the vehicle is subjected to vibrations when driving, and the door can slightly move. The latches bumpers help limiting those door movements. These are thus important elements for the door stability of the moving vehicle that also have an influence directly on other comfort settings such as acoustic comfort.

[0004] These bumpers are usually mounted on fixed elements of the latch. When the door is closing, the claw hits the fixed bumper and transmits energy to the element holding the fixed bumper.SUMMARY OF THE INVENTION

[0005] The purpose of the invention is to simplify the door latch manufacturing method.

[0006] To this effect, the present invention refers to a door latch for closing a door of a motor vehicle comprising: a claw having a recess to catch a striker in a closed position, the claw being configured to rotate between an open position and a closed position, a pivoting pawl configured to interact with said claw in the closed position to prevent a rotation in open position of said claw, wherein the claw comprises an embedded bumper configured to hit an end stop of the door latch when the claw rotates in the closed position.

[0007] Thus, when the claw is rotated to close, the embedded bumper is also rotated until the embedded bumper hits the end stop which stops the rotation. The embedded bumper helps dissipating energy when the vehicle door closes and helps immobilizing the vehicle door on the vehicle body through the striker / claw connection, when the vehicle is in movement.

[0008] The embedded bumper can be very small as only the needed material is embedded. Indeed, the embedded bumper is easier to fix to the claw, contrary to the prior art bumper that has to go all around the end stop to be securely fixed. Cost can then be reduced, and the design can be simplified. Moreover, it saves space in the door latch. Another advantage is that this allows balancing the claw inertia by modifying its center of gravity.

[0009] The door latch can also comprise one or more of the features which are described hereinbelow, taken alone or in combination.

[0010] The embedded bumper may be located on one of the fork branch of the claw forming the recess, the fork branch being the one which is engaged with the pawl in the closed position.

[0011] The embedded bumper may be housed at least partially inside a notch of a body of the claw.

[0012] The notch can be laterally at least partially closed to retain the embedded bumper.

[0013] According to an embodiment, the notch has a C-form and the embedded bumper is cylindrical.

[0014] The embedded bumper may be realized in plastic such as a thermoplastic elastomer such as a thermoplastic polyurethane or such as nitril rubber.

[0015] The embedded bumper might have been overmolded on a body of the claw.

[0016] According to an embodiment, the embedded bumper is made of two plastic materials, a first plastic being overmolded on a body of the claw and a second plastic being overmolded on the first plastic.

[0017] According to an embodiment, the embedded bumper is bi-injected.

[0018] Another object of the present invention is a claw comprising an embedded bumper configured to hit an end stop of the door latch when the claw rotates in the closed position.

[0019] Another object of the present invention is a manufacturing method of a claw as previously disclosed wherein the embedded bumper is assembled to the body of the claw by being introduced in a notch of the body of the claw.

[0020] Another object of the present invention is a manufacturing method of a claw as previously disclosed wherein the embedded bumper is assembled to the body of the claw by being overmolded on the body of the claw.

[0021] The invention will be better understood in view of the following description, referring to the annexed figures in which: [Fig.1] Figure 1 is a perspective view of a door latch for closing a door of a motor vehicle in a closed position. [Fig.2] Figure 2 is an enlarged detail of the door latch of Figure 1. [Fig.3] Figure 3 is another view of some elements of the door latch of Figure 1. [Fig.4] Figure 4 is another view of the door latch of figure 1. [Fig.5] Figure 5 is a view of the claw of the door latch of figure 1 during a first step of manufacturing. [Fig.6] Figure 6 is a similar view than Figure 5 during a successive step of manufacturing. DETAILED DESCRIPTION OF THE INVENTION

[0022] The following achievements are examples. Although the specification refers to one or several embodiments, it does not imply that each reference refers to the same embodiment or that the features apply only to a single embodiment. Simple features of different embodiments can also be combined to provide other embodiments.

[0023] Figure 1 represents a door latch 1 for closing a door of a motor vehicle particularly a side door or a trunk lid or similar.

[0024] The door latch 1 comprises a rotating claw 2 configured to rotate between an open position (not represented) and a closed position (figure 1). In the closed position, a striker 5 (visible in Figures 3 and 4) associated to the door of the vehicle is trapped in the recess 4 of the claw 2, holding the vehicle door in the closed state.

[0025] The door latch 1 also comprises a pivoting pawl 6 configured to interact with said claw 2 in the closed position to prevent a rotation of said claw 2 in open position (clockwise in figure 1).

[0026] For example, the claw 2 comprises at least a catch 3 designed to interact with an end 6a of the pawl 6 configured to prevent the claw 2 from rotating when the claw 2 is in closed position.

[0027] The pawl 6 is designed to be operated by an actuator for opening the door latch 1. The pawl 6 may be subjected to an elastic return force which pushes it toward the claw 2. The claw 2 may be subjected to an elastic force which pushes it in the open position.

[0028] The claw 2 further comprises an embedded bumper 7 configured to hit an end stop 8 of the door latch 1 when the claw 2 rotates in the closed position (anticlockwise in figure 1). The end stop 8 is fixed in the door latch 1, for example to a frame 12 of the door latch 1. The end stop 8 is for example made in one piece with the frame 12.

[0029] According to one embodiment, the embedded bumper 7 is located on one of the fork branch 9 of the claw 2 forming the recess 4, the fork branch 9 being the one which is engaged with the pawl 6 in the closed position. This makes this fork branch 9 of the claw 2 heavier. This heavier fork branch 9 makes it easier for the claw 2 to rotate in the closed position (anticlockwise in figure 1) and makes the introduction of the striker 5 in the recess 4 of the claw 2 easier.

[0030] According to one embodiment, the embedded bumper 7 is housed at least partially inside a notch 10 of a body 11 of the claw 2 (figure 2). The notch 10 can be laterally at least partially closed to retain the embedded bumper 7, such as extending over more than half of the side of the notch 10.

[0031] According to the embodiment of figures 1 and 2, the side cover of the notch 10 has apertures. On another embodiment not illustrated, the notch 10 is laterally partially closed, such as extending over more than half of the side of the notch 10, without apertures on the side cover of the notch 10.

[0032] The notch 10 may be made in a side of the body 11 of the claw 2. As example, the body 11 comprises a main part 11a which is at least partially interposed (sandwiched) between two plates 11b, 11c. The whole body 11 may be metallic, such as in steel material. The plates 11b, 11c extend on both sides of the main part 11a of the body 11 to laterally close the notch 10.

[0033] The notch 10 and the embedded bumper 7 may have complementary shapes. As example, the notch 10 made in the main part 11a has a C-form and the embedded bumper 7 is cylindrical, the axis of the cylinder being parallel to the axis of rotation of the claw 2 and of the pawl 6. During functioning, each time the embedded bumper 7 hits the end stop 8, the hitting force tends to engage further the embedded bumper 7 towards the bottom of the notch 10.

[0034] The embedded bumper 7 may be realized in plastic such as a thermoplastic elastomer such as a thermoplastic polyurethane or such as nitril rubber, which offers high wear resistance, flexibility across a wide range of temperatures and which is mechanically stable enough to well absorb and dissipate energy in a very short stroke.

[0035] During a first example of manufacturing method of the claw 2, the embedded bumper 7 may be assembled to the body 11 of the claw 2 by introducing the embedded bumper 7 in the notch 10 of the body 11 of the claw 2 (see as example figures 5 and 6).

[0036] According to another manufacturing method of the claw 2, the embedded bumper 7 is assembled to the body 11 of the claw 2 by being overmolded on the body 11 of the claw 2.

[0037] In one embodiment, the embedded bumper 7 may be made of two different plastic materials. The first plastic may be overmolded on the body 11 of the claw 2 while a second plastic such as a thermoplastic elastomer such as a thermoplastic polyurethane or nitril rubber may be overmolded on the first plastic.

[0038] According to another embodiment, the embedded bumper 7 is bi-injected where be-injected means that an overmold is injected during a first injection to form the plates 11b, 11c and a second plastic is injected during a second be-injection to form the bumper 7. Preferably, the second plastic of the bumper 7 has a lower shore hardness than the first plastic of the plates 11b and 11c.

[0039] Thus, when the claw 2 is rotated to close, the embedded bumper 7 is also rotated until the embedded bumper 7 hits the end stop 8 which stops the rotation. The embedded bumper 7 helps dissipating energy when the vehicle door closes and helps immobilizing the vehicle door on the vehicle body through the striker 5 / claw 2 connection, when the vehicle is in movement.

[0040] The embedded bumper 7 can be very small as only the needed material is embedded. Indeed, the embedded bumper 7 is easier to fix to the claw 2, contrary to the prior art bumper that has to go all around the end stop 8 to be securely fixed. Cost can then be reduced, and the design can be simplified. Moreover, it saves space in the door latch 1. Another advantage is that this allows balancing the claw 2 inertia by modifying its center of gravity.

Claims

1. A door latch (1) for closing a door of a motor vehicle comprising: - a claw (2) having a recess (4) to catch a striker (5) in a closed position, the claw (2) being configured to rotate between an open position and a closed position, - a pivoting pawl (6) configured to interact with said claw (2) in the closed position to prevent a rotation in open position of said claw (2), wherein the claw (2) comprises an embedded bumper (7) configured to hit an end stop (8) of the door latch (1) when the claw (2) rotates in the closed position.

2. Door latch (1) according to claim 1, wherein the embedded bumper (7) is located on one of the fork branch (9) of the claw (2) forming the recess (4), the fork branch (9) being the one which is engaged with the pawl (6) in the closed position.

3. Door latch (1) according to one of the previous claims, wherein the embedded bumper (7) is housed at least partially inside a notch (10) of a body (11) of the claw (2).

4. Door latch (1) according to the previous claim, wherein the notch (10) is laterally at least partially closed to retain the embedded bumper (7).

5. Door latch (1) according to one of claims 3 or 4, wherein the notch (10) has a C-form and the embedded bumper (7) is cylindrical.

6. Door latch (1) according to one of previous claims, wherein the embedded bumper (7) is realized in plastic such as a thermoplastic elastomer such as a thermoplastic polyurethane or such as nitril rubber.

7. Door latch (1) according to the previous claims, wherein the embedded bumper (7) is overmolded on a body (11) of the claw (2).

8. Door latch (1) according to one of claims 1 to 5, wherein the embedded bumper (7) is made of two plastic materials, a first plastic being overmolded on a body (11) of the claw (2) and a second plastic being overmolded on the first plastic or the embedded bumper (7) being bi-injected.

9. Claw (2) for a door latch (1) according to one of the previous claims wherein the claw (2) comprises an embedded bumper (7) configured to hit an end stop (8) of the door latch (1) when the claw (2) rotates in the closed position.

10. Manufacturing method of a claw (2) according to the previous claims wherein the embedded bumper (7) is assembled to the body (11) of the claw (2) by being introduced in a notch (10) of the body (11) of the claw (2) or overmolded on the body (11) of the claw (2).

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