Locking assembly with a locking mechanism with double pawl and single ratchet

Abstract

A closure latch assembly (10) for a vehicle closure door (12), comprising: a ratchet (32) movable between a primary striker receiving position, a secondary striker receiving position, and a striker releasing position; a ratchet biasing member (32a) configured to apply a biasing force to the ratchet (32) to bias the ratchet (32) toward the striker releasing position; a primary pawl (36a) movable about a primary pawl pivot (36R) between a primary ratchet holding position, in which the primary pawl (36a) holds the ratchet (32) in the primary striker receiving position, and a ratchet release position, in which the primary pawl (36a) allows movement of the ratchet (32) toward the striker release position; and a secondary pawl (36b),which is movable about a secondary pawl pivot (36r) between a secondary ratchet holding position, in which the secondary pawl (36b) holds the ratchet (32) in the secondary striker receiving position, and a ratchet release position, in which the secondary pawl (36b) allows the ratchet to move towards the striker releasing position, wherein, while the ratchet (32) is in the primary striker receiving position, the biasing force exerted on the ratchet (32) by the ratchet biasing member (32a) is counteracted by a reaction force exerted by the primary pawl pivot (36r), wherein, while the ratchet (32) is in the secondary striker receiving position,the preload force exerted by the ratchet preloading member (32a) on the ratchet (32) is counteracted by a reaction force exerted by the primary pawl pivot (36R).

Description

REGIONThe present disclosure relates generally to power door systems for motor vehicles. More particularly, the present disclosure relates to a power operated door system equipped with a power operated latch assembly having a double pawl and single ratchet release mechanism.PRIOR ARTIn view of the increased consumer demand for motor vehicles having modern convenience and convenience features, many current vehicles are now equipped with power-operated latch assemblies that include a primary pawl movable between a primary ratchet holding position in which a ratchet gear is retained in a primary striker receiving position and a ratchet release position in which the ratchet gear is free to move from the primary striker receiving position, and a secondary pawl movable between a secondary ratchet holding position in which the ratchet gear is retained in a secondary striker receiving position and a ratchet release position in which the ratchet gear is free to move from the secondary striker receiving position. While the ratchet gear is in the primary striker receiving position, the primary pawl carries the full load of the ratchet gear, and while the ratchet gear is in the second striker receiving position, the secondary pawl carries the full load of the ratchet gear. In this respect, both the primary pawl and the secondary pawl must be sufficiently supported and strong enough to be able to carry the full load of the ratchet wheel. While such power latch assemblies provide the desired functionality, further improvements are desired to reduce package size while using as few components as possible and to be economical to manufacture.In view of the foregoing, there remains a need to develop alternative power door latch assemblies that address and overcome the limitations associated with known power door latch assemblies to provide improved functionality while minimizing the cost and complexity associated with such advances.SUMMARYAn aspect of the present disclosure is to provide a closure latch assembly for a vehicle closure door, wherein the closure latch assembly has a minimum number of components and is economical to manufacture.A closure latch assembly for a vehicle closure door is provided. The latch assembly includes a ratchet gear movable between a primary striker receiving position, a secondary striker receiving position, and a striker release position. A ratchet biasing member is configured to apply a biasing force to the ratchet gear to bias the ratchet gear toward the striker release position. A primary pawl is movable about a primary pawl pivot between a primary ratchet holding position, in which the primary pawl holds the ratchet gear in the primary striker receiving position, and a ratchet release position, in which the primary pawl permits the ratchet gear to move toward its striker release position. A secondary pawl is movable about a secondary pawl pivot between a secondary ratchet holding position, in which the secondary pawl holds the ratchet gear in the secondary striker receiving position, and a ratchet release position, in which the secondary pawl permits the ratchet gear to move toward its striker release position. While the ratchet gear is in the primary striker receiving position, the biasing force applied to the ratchet gear by the ratchet biasing member is counteracted by a reaction force applied by the primary ratchet pivot, and while the ratchet gear is in the secondary striker receiving position, the biasing force applied to the ratchet gear by the ratchet biasing member is counteracted by a reaction force applied by the primary ratchet pivot.According to another aspect of the disclosure, the secondary pawl includes a first leg extending to a first end and a second leg extending to a second end, wherein the secondary pawl pivot extends through the first leg and the second leg engages the primary pawl pivot while the ratchet gear is in the secondary striker receiving position.According to another aspect of the disclosure, an intermediate arm extends between the first leg and the second leg, the second leg configured to engage a secondary ratchet stop pin while the ratchet gear is in the secondary striker receiving position.According to another aspect of the disclosure, the second leg extends between the secondary ratchet stop pin and the primary ratchet pivot.According to another aspect of the disclosure, the secondary ratchet stop pin is configured between the first leg and the second leg while the ratchet gear is in the secondary striker receiving position.According to another aspect of the disclosure, the second leg includes a secondary notch configured to engage the secondary ratchet stop pin while the ratchet gear is in the secondary striker receiving position.According to another aspect of the disclosure, the secondary pawl is generally C-shaped.According to another aspect of the disclosure, the secondary pawl is biased toward its secondary ratchet holding position.According to another aspect of the disclosure, the primary pawl and the secondary pawl are non-coplanar.According to another aspect of the disclosure, the secondary pawl overlaps at least a portion of the ratchet gear and the primary pawl while the ratchet gear is in the secondary striker receiving position.Further areas of applicability will become apparent from the description provided herein.BRIEF DESCRIPTION OF THE DRAWINGSThe drawings described herein have been provided to illustrate selected embodiments and specific features thereof and are not intended to limit the scope of the present disclosure. The present disclosure will now be described, by way of example only, with reference to the appended drawings. FIG. 1 is a perspective view of a motor vehicle having a vehicle closure door equipped with a closure latch assembly constructed in accordance with several aspects of the disclosure; FIG. 2 is a perspective view of a latch assembly of FIG. 1 and components thereof, according to an aspect of the disclosure, showing a ratchet gear of the latch assembly held in a primary striker receiving position by a primary pawl; FIGS. 3A and 3B illustrate the primary pawl in a primary ratchet holding position to hold the ratchet gear in the primary striker receiving position; FIG. 3C is a view of a secondary pawl while the primary pawl is in the primary ratchet holding position; FIGS. 4A through 4E illustrate a secondary pawl in a secondary ratchet holding position to hold the ratchet in a secondary striker receiving position; FIG. 4F is a view of the primary pawl while the secondary pawl is in the secondary ratchet holding position; FIG. 5A illustrates the primary pawl while the ratchet gear is in a striker release position; and FIG. 5B illustrates the secondary pawl while the ratchet gear is in the striker release position.DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTSReferring first to FIG. 1, a closure latch assembly, also referred to as a closure latch or latch assembly 10, for a motor vehicle closure door, such as a swing door shown as a back door 12, of a motor vehicle 14, is shown positioned, by way of example and without limitation, along a closure surface portion 16 of the door 12 and is configured to releasably engage and receive a striker 18 secured to a vehicle body 22 to extend into a door opening 20 formed in the vehicle body 22 in response to movement of the door 12 from an open position to a closed position. The door 12 is shown to include an outer door handle 24 and an inner door handle 26, both of which are operatively (i.e., electrically and / or mechanically) connected to the closure latch assembly 10. Although not shown, it should be appreciated that a similar closure latch assembly is provided in connection with a front door 13 of a vehicle 14 shown to include a separate exterior door handle 25.Referring now to FIG. 2, a non-limiting example embodiment of the closure latch assembly 10 and internal components thereof including a latch mechanism 31 is shown, wherein the latch mechanism 31 of the closure latch assembly 10 is shown in a closed, locked position in FIG. 2. The locking mechanism 31 is shown to include a ratchet 32, a primary pawl 36a, a secondary pawl 36b, and an auxiliary pawl. The ratchet gear 32 is pivotally mounted to at least one plate segment shown supported for pivotal movement about a ratchet rivet, also referred to as ratchet pin 32b, the ratchet pin 32b being supported at opposite ends by a frame plate 28a and a back plate 28b of a lock housing. The ratchet gear 32 has a ratchet gear slot 34 alignable with a fish mouth slot 30 formed in the frame plate 28a. The ratchet gear 32 is movable between a primary closed or "primary striker receiving" position (FIGS. 2-3C ) in which the striker 18 is held in the fish mouth slot 30 by being received in the ratchet gear slot 34, a secondary striker receiving position (FIGS. 4A, 4B, 4E, and 4F ), and an open or "striker release" position (FIGS. 5A and 5B ) in which the striker 18 can be freely released from the ratchet gear slot 34 and the fish mouth slot 30. The ratchet gear 32 is biased by a ratchet biasing member 32 a, such as a ratchet spring, such that the ratchet spring 32 aapplies a biasing force to the ratchet gear 32 to bias the ratchet gear 32 toward its striker release position.The primary pawl 36a is pivotally supported by a primary pawl pivot, also referred to as a primary pivot, shown exemplarily and without limitation as defined by a primary pawl rivet 36R, for movement with a first plane between a secured primary ratchet holding position, also referred to as a "closed" position, in which the primary pawl 36a locates and holds the ratchet gear 32 in its primary striker receiving position, and an unsecured primary ratchet release position, also referred to as an "open" position, in which the primary pawl 36a is positioned to allow the ratchet gear 32 to move to its striker release position, as under a bias applied to the ratchet gear 32 by the ratchet spring 32a. A primary pawl biasing member 36c, such as a pawl spring, serves to normally bias the primary pawl 36a toward its closed position.The secondary pawl 36 bis pivotally supported by a secondary pawl pivot, also referred to as a secondary pivot, shown exemplarily and without limitation as defined by a secondary pawl rivet 36 r, for movement within a second plane between a secured secondary ratchet holding position, also referred to as a "partially closed" position, in which the secondary pawl 36 blocates and holds the ratchet gear 32 in its secondary striker receiving position, and an unsecured secondary ratchet release position, also referred to as an "open" position, in which the secondary pawl 36 bis positioned to allow the ratchet gear 32 to move to its striker release position, as under a bias applied to the ratchet gear 32 by the ratchet spring 32 a. The first plane P 1 in which the primary pawl 36 aboves and the second plane P 2 in which the secondary pawl 36 bbove are not coplanar but parallel to each other as shown in FIG. 4D, such that the primary pawl 36 aand the secondary pawl 36 blap and pass each other during the respective pivoting movement. The ratchet gear 32 pivots within the first plane P 1, and thus the secondary pawl 36 blaps at least a portion of the ratchet gear 32 and the primary pawl 36 awhile the ratchet gear 32 is in the secondary striker receiving position. A secondary pawl biasing member 36d, such as a secondary pawl spring, serves to normally bias the secondary pawl 36b toward its partially closed position. Secondary pawl 36b is shown to include a generally C-shaped body having a pair of opposing legs 39a, 39b interconnected by an intermediate arm 39c. Accordingly, the intermediate arm 39c extends between the first leg 39a and the second leg 39b. The opposing legs 39a, 39b, also referred to as first leg 39a and second leg 39b, extend from the intermediate arm 39c in generally mirrored, parallel relationship to each other. The secondary pawl rivet 36 rsupports the secondary pawl 36 bfor pivotal movement adjacent one end 41 a, also referred to as a first end 41 a, of the leg 39 aof the C-shaped body such that the secondary pawl rivet 36 rextends through the first leg 39 aand a secondary notch 42 is formed adjacent the opposite end 41 b, also referred to as a second end 41 b, of the C-shaped body within the second leg 39 bor within a region where the second leg 39 bchanges into the arm 39 c. The secondary notch 42 is configured for engagement with a secondary ratchet stop pin 44 that is attached to and extends laterally from the ratchet gear 32 while the ratchet gear 32 is in the secondary striker receiving position, and the second leg 39 bextends between the secondary ratchet stop pin 44 and the primary ratchet pivot 36R. The secondary stop pin 44 extends along an axis that is generally parallel to a pivot axis defined by the ratchet pin 32b about which the ratchet gear 32 pivots.The auxiliary pawl 33 is pivotally supported by an auxiliary pawl pivot, also referred to as an auxiliary pivot, shown by way of example and without limitation as defined by an auxiliary pawl rivet 33R, for movement with a secured primary pawl blocking position in which the auxiliary pawl 33 maintains the primary pawl 36a in its closed position and a primary pawl releasing position in which the auxiliary pawl 33 is positioned such that the primary pawl 36a can be moved to its open position. An auxiliary pawl biasing member 33a, such as an auxiliary pawl spring, serves to normally bias the auxiliary pawl 33 toward its primary pawl blocking position.In operation, while the ratchet gear 32 is in the primary striker receiving position, a first arm 33 bof the auxiliary pawl 33 blocks movement of the primary pawl 36 away from its primary ratchet holding position, and the biasing force applied by the ratchet biasing member 32 ato the ratchet gear 32 is transmitted through the primary pawl 36 aand compensated by a reaction force 46 (FIG. 3B ) applied by the primary pawl pivot 36R. During operation of a pawl release lever, also referred to as pawl lever 35 (FIG. 2 ), a pawl lever 35 is pivoted about the primary pawl rivet 36R in a counterclockwise direction as viewed in FIG. 2, thereby moving a first arm 35 aof the pawl lever 35 into engagement with a second arm 33 cof the auxiliary pawl 33 to rotate the auxiliary pawl 33 clockwise from blocking engagement with the primary pawl 36 awhile simultaneously engaging and forcibly driving a leg 37 of the primary pawl 36 to pivot the primary pawl 36 afrom its primary ratchet holding position to its primary ratchet release position against the bias exerted by the primary pawl biasing member 36 c. When the primary pawl 36a is moved to its primary ratchet release position, the ratchet gear 32 moves to its secondary striker receiving position. While the ratchet gear 32 is in the secondary striker receiving position, the biasing force applied by the ratchet biasing member 32 ato the ratchet gear 32 is transmitted into the leg 39 bthrough the leg 39 b(FIGS. 4B and 4C ) of the secondary pawl 36 bvia engagement of the secondary ratchet stop pin 44 with the secondary notch 42 and is balanced by a reaction force 48 applied by the primary pawl pivot 36R to the leg 39 b(FIG. 4B ). Accordingly, because the reaction force 48 is supported by and extends through the primary pawl pivot 36R and the leg 39 bof the secondary pawl 36 b, from the point of contact with the primary pawl rivet 36R to the secondary pawl pivot 36 r, and not, at least not to any appreciable extent, supported by or extending through the arm 39 cor the leg 39 aof the secondary pawl 36 b, the size, structural strength, and weight of the primary pawl rivet 36R, the leg 39 a, and the arm 39 cof the secondary pawl 36 bmay be reduced provided that only little force is transmitted through the primary pawl rivet 36R, the arm 39 c, and the leg 39 aof the secondary pawl 36 b. Then, when the ratchet gear 32 is to be moved from its secondary striker receiving position to its striker release position, the ratchet lever 35 may be further pivoted about the primary ratchet rivet 36R counterclockwise as viewed in FIG. 2, thereby moving a second arm 35 bof the ratchet lever 35 into engagement with an upstanding secondary ratchet pin 38 of the secondary ratchet 36 bto rotate the secondary ratchet 36 bin the clockwise direction from its secondary ratchet holding position to its secondary ratchet release position against the bias exerted by the secondary ratchet biasing member 36 d, whereby the ratchet gear 32 may freely move from its secondary striker receiving position to its striker release position.

Claims

A closure latch assembly (10) for a vehicle closure flap (12), comprising: a ratchet gear (32) movable between a primary striker receiving position, a secondary striker receiving position, and a striker release position; a ratchet biasing member (32a) configured to apply a biasing force to the ratchet gear (32) to bias the ratchet gear (32) toward the striker release position; a primary pawl (36a) movable about a primary pawl pivot (36R) between a primary ratchet gear retaining position in which the primary pawl (36a) retains the ratchet gear (32) in the primary striker receiving position and a ratchet release position in which the primary pawl (36a) permits movement of the ratchet gear (32) toward the striker release position; and a secondary pawl (36b) movable about a secondary pawl pivot (36r) between a secondary ratchet wheel retaining position in which the secondary pawl (36b) retains the ratchet wheel (32) in the secondary striker receiving position and a ratchet wheel release position in which the secondary pawl (36b) permits the ratchet wheel to move toward the striker release position, wherein, while the ratchet wheel (32) is in the primary striker receiving position, the biasing force exerted on the ratchet wheel (32) by the ratchet wheel biasing member (32a) is counteracted by a reaction force exerted by the primary pawl pivot (36R), wherein, while the ratchet wheel (32) is in the secondary striker receiving position, the biasing force applied to the ratchet gear (32) by the ratchet biasing member (32a) is counteracted by a reaction force applied by the primary ratchet pivot (36R).The latch assembly of claim 1, wherein the secondary pawl (36b) has a first leg (39a) extending to a first end (41a) and a second leg (39b) extending to a second end (41b), wherein the secondary pawl pivot (36r) extends through the first leg (39a), and wherein the second leg (39b) engages the primary pawl pivot (36R) while the ratchet gear (32) is in the secondary striker receiving position.The closure latch assembly of claim 2, wherein an intermediate arm (39c) extends between the first leg (39a) and the second leg (39b), the second leg (39b) configured to engage a secondary ratchet stop pin (44) while the ratchet gear (32) is in the secondary striker receiving position.The closure latch assembly of claim 2 or 3, wherein the second leg (39b) extends between the secondary ratchet stop pin (44) and the primary ratchet pivot pin (36R).The closure latch assembly of any of claims 2 to 4, wherein the secondary ratchet stop pin (44) is disposed between the first leg (39a) and the second leg (39b) while the ratchet gear (32) is in the secondary striker receiving position.The closure latch assembly of any of claims 2 to 5, wherein the second leg (39b) includes a secondary notch (42) configured to engage the secondary ratchet stop pin (44) while the ratchet gear (32) is in the secondary striker receiving position.The latch assembly of any of claims 3 to 6, wherein the secondary pawl (36b) is generally C-shaped.The latch assembly of any of claims 1 to 7, wherein the secondary pawl (36b) is biased toward its secondary ratchet holding position.The latch assembly of any of claims 1 to 8, wherein the primary pawl (36a) and the secondary pawl (36b) are non-coplanar.The latch assembly of claim 9, wherein the secondary pawl (36b) overlaps at least a portion of the ratchet gear (32) and the primary pawl (36a) while the ratchet gear (32) is in the secondary striker receiving position.

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