Vehicular latch with double pawl arrangement

Patent metadata

Field	Value
Publication number	US-9765554-B2
Application number	US-201013577059-A
Country	US
Kind code	B2
Filing date	Nov 26, 2010
Priority date	May 26, 2008
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

A low release effort eccentric double pawl vehicle latch includes a ratchet, primary pawl, auxiliary ratchet and secondary pawl in combination with a secure lock lever. The secure lock lever selectively inhibits movement of the secondary pawl to prevent premature or unintended opening of the latch. A drive mechanism sequences movement of the secure lock lever and secondary pawl to open the latch. Upon reset, the drive mechanism drives the auxiliary ratchet back to its closed state and in the process the auxiliary ratchet can engage and return the secondary pawl back to a closed state in the event of an insufficient bias force thereon.

First claim

The invention claimed is:

1. A vehicle latch, comprising:
a ratchet movable between a striker release position wherein the ratchet is positioned to receive a striker and a striker capture position wherein the ratchet is positioned to retain the striker, the ratchet being biased towards the striker release position;
a primary pawl movable between a ratchet checking position wherein the primary pawl is positioned to keep the ratchet in the striker capture position and a ratchet release position wherein the primary pawl permits the movement of the ratchet out of the striker capture position, the primary pawl being biased towards the ratchet checking position;
an auxiliary ratchet pivotably supporting the primary pawl, the auxiliary ratchet being movable between an enabling position in which the primary pawl is enabled to move to its ratchet checking position and a disabling position in which the auxiliary ratchet positions the primary pawl to its ratchet release position;
a secondary pawl movable between an auxiliary ratchet holding position, in which the secondary pawl is positioned to hold the auxiliary ratchet in its enabling position, and an auxiliary ratchet release position, in which the secondary pawl is positioned to permit movement of the auxiliary ratchet to its disabling position, the secondary pawl being biased to the auxiliary ratchet holding position;
a secure lock lever selectively engageable with the secondary pawl and movable between a locking position, wherein the secure lock lever directly engages the secondary pawl to prohibit movement out of its auxiliary ratchet holding position, and a releasing position, wherein the secure lock lever disengages the secondary pawl to enable movement into its auxiliary ratchet release position, the secure lock lever being biased to the locking position; and
a drive mechanism including a gear wheel for moving the secure lock lever into its releasing position and moving the secondary pawl into its auxiliary ratchet release position;
wherein the primary pawl is pivotally mounted to the auxiliary ratchet and the primary pawl moves with the auxiliary ratchet between its enabling position and its disabling position.

2. A vehicle latch according to claim 1 , wherein the drive mechanism also moves the auxiliary ratchet to its disabling position in the event the auxiliary ratchet does not enter its disabling position upon movement of the secondary pawl out of its auxiliary ratchet holding position, whereby the primary pawl is moved into its ratchet release position.

3. A vehicle latch according to claim 2 , wherein the drive mechanism is controlled to: first open the latch so as to move the secure lock lever into its releasing position move the secondary pawl into its auxiliary ratchet release position, and, if required, move the auxiliary ratchet to its disabling position, whereby the ratchet moves into its striker release position; then, prior to the ratchet moving to its striker capture position, immediately reset the latch so as to move the auxiliary ratchet to its enabling position; enable the secondary pawl to move into its auxiliary ratchet holding position, and enable the secure lock lever to move into its locking position.

4. A vehicle latch according to claim 1 , wherein the auxiliary ratchet is configured to engage and move the secondary pawl into its auxiliary ratchet holding position as the auxiliary ratchet moves towards its enabled position.

5. A vehicle latch according to claim 1 , wherein: the gear wheel has a well therein;
the secure lock lever is pivotally mounted in the latch and has a first portion and a second rigidly connected portion, wherein when the second portion is positioned in the gear wheel well the first portion blocks the secondary pawl from movement and when the second portion is moved by the drive mechanism out of the well the first portion does not block the secondary pawl from movement.

6. A vehicle latch according to claim 1 , wherein: the gear wheel has a well therein; the auxiliary ratchet has a post; and the auxiliary ratchet post is disposed in the gear wheel well and engaged by one or more walls thereof.

7. A vehicle latch according to claim 1 , wherein: the drive mechanism includes a gear wheel having a push block; the secondary pawl has an abutment; and the gear wheel push block engages the secondary pawl abutment to drive the secondary pawl into its auxiliary ratchet release position.

8. A vehicle latch according to claim 1 , wherein the auxiliary ratchet is pivotal about a first axis, and wherein the primary pawl is pivotally mounted to the auxiliary ratchet about a second axis that is offset from the first axis.

9. A vehicle latch according to claim 8 , wherein, in use, the ratchet is engageable with the striker to receive a door seal force (Fs) from the striker, wherein, when the primary pawl is in the ratchet checking position the ratchet is positioned to receive the door seal force (Fs) and to transmit a corresponding second force (Fs*X/Y) in a second force direction that is approximately intersectant with the second axis, and wherein the corresponding second force is transmittable from the primary pawl into the auxiliary ratchet in such a way as to generate a moment (M 2 ) that urges the auxiliary ratchet towards its disabling position.

10. A vehicle latch, comprising:
a ratchet movable between a striker release position wherein the ratchet is positioned to receive a striker and a striker capture position wherein the ratchet is positioned to retain the striker, the ratchet being biased towards the striker release position;
a primary pawl movable between a ratchet checking position wherein the primary pawl is positioned to keep the ratchet in the striker capture position and a ratchet release position wherein the primary pawl permits the movement of the ratchet out of the striker capture position;
an auxiliary ratchet operatively connected to the primary pawl, the auxiliary ratchet being movable between an enabling position in which the primary pawl is enabled to move to its ratchet checking position and a disabling position in which the auxiliary ratchet positions the primary pawl to its ratchet release position;
a secondary pawl movable between an auxiliary ratchet holding position, in which the secondary pawl is positioned to hold the auxiliary ratchet in its enabling position, and an auxiliary ratchet release position, in which the secondary pawl is positioned to permit movement of the auxiliary ratchet to its disabling position, the secondary pawl being biased to the auxiliary ratchet holding position; and
a drive mechanism for moving the secondary pawl into its auxiliary ratchet release position in a process of opening the latch and for later moving the auxiliary ratchet into its enabling position in a process of closing the latch;
wherein the auxiliary ratchet is configured to engage and move the secondary pawl into its auxiliary ratchet holding position as the auxiliary ratchet moves towards its enabled position.

11. A vehicle latch, comprising:
a ratchet movable between a striker release position wherein the ratchet is positioned to receive a striker and a striker capture position wherein the ratchet is positioned to retain the striker, the ratchet being biased towards the striker release position;
a primary pawl movable between a ratchet checking position wherein the primary pawl is positioned to keep the ratchet in the striker capture position and a ratchet release position wherein the primary pawl permits the movement of the ratchet out of the striker capture position, the primary pawl being biased towards the ratchet checking position;
an auxiliary ratchet operatively connected to the prima

Assignees

• Cumbo Francesco
• Taurasi Marco
• Magna Closures Inc

Inventors

• Cumbo Francesco
• Taurasi Marco

Classifications

• E05B85/26

  Cooperation between bolts and detents · CPC title

• Y10T292/1079

  Gear · CPC title

• E05B81/14 Primary

  operating on bolt detents, e.g. for unlatching the bolt · CPC title

• Y10T292/108

  Lever · CPC title

• E05B81/90

  Manual override in case of power failure · CPC title