Patent Publication Number: US-9428943-B2

Title: Modular latch

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a national entry application of PCT International Application No. PCT/CA2008/000380 filed Feb. 28, 2008 which claims the benefit of U.S. Provisional Application No. 60/892,031, filed Feb. 28, 2007, the contents of which are incorporated herein in their entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to automotive door latches, such as may be used in such things as lift gates, deck lids, or sliding doors. 
     BACKGROUND OF THE INVENTION 
     Latch designs need to accommodate different packaging requirements for lift gates, decklids and sliding doors. In addition, automotive companies are looking to provide new features for their vehicles, even on components such as latches. Features such as power locking, power releasing and power cinching are rapidly becoming popular. Other manufacturers desire simpler and less expensive locks. The need for multiple latch packages and feature sets results in the need for multiple latch designs while manufacturers are looking to standardize parts in order to reduce assembly costs. Therefore, it may be desirable to produce a modular latch that can accommodate different features within one assembly. 
     Additionally, in a vehicle collision, there is the potential that sudden deceleration may generate an inertial load on either the ratchet or pawl to accidentally release the latch. This may not be desirable. 
     For latches with power cinching, the controller needs to know the position of the ratchet (released, primary engaged, secondary engaged position), in order to know when to begin and when to stop the cinching motor. Typically, switches triggered by either the ratchet or the pawl, or both, tend to report on the ratchet position.  FIG. 1 a    shows a prior art switching strategy. One switch is triggered by the ratchet, and another switch is triggered by the pawl. The ratchet switch has an OFF state when the ratchet is rotated into the release position, and an ON state when the ratchet is rotates past the secondary and preferably close to the primary engagement positions. To compensate for operational variances, there is a slight lag between the ratchet reaching the primary engagement position and the ratchet switch indicating that the ratchet is engaged. The pawl switch has a OFF position that corresponds to the pawl being actuated away from the ratchet, and an ON position, which corresponds to when the pawl retains the ratchet in either the secondary or primary engagement positions. One problem with this switch strategy is that the switches report the same state (OFF and OFF) when the ratchet is in the primary engagement position, and an interlude between the primary and secondary engagement positions. The controller is forced to use additional intelligence to provide the desired cinching effect, resulting in increased complexity and more expensive components. 
     A second prior art switch strategy, shown in  FIG. 1 b   , uses two switches, but with both switches contacting the ratchet at different parts of the ratchet&#39;s travel between released, secondary engagement and primary engagement positions. The first ratchet switch works as the ratchet switch described above. The second ratchet switch is positioned elsewhere along the ratchet&#39;s travel path so that it is off when the ratchet is released, switches ON while the ratchet travels from secondary to primary engagement positions, and then switches off again. As before, operational variances require that there be a lag between the transition of the switch state and the ratchet position. While this switch strategy avoids the OFF, OFF scenario described above, the second ratchet switch is not turned off until after the ratchet reaches the primary engagement position. This results in the motor continuing to cinch briefly, but disquietingly, after the latch is fully closed in the primary engagement position. 
     Finally, it is generally desirable to reduce the cost of producing the latch. This includes reducing the product design and development costs, design validation and production validation test costs by using previously designed and validated components. This may reduce the number of components used during assembly, the time required to assemble the latch, and the cost of the components generally. 
     SUMMARY OF THE INVENTION 
     In an aspect of the invention there is a modular latch for an automotive vehicle. It has a latch core. The latch core has a housing and a ratchet and pawl rotatably mounted to the housing. The ratchet and pawl are cooperatively operable to move between an engaged position to hold a striker and a released position. The latch core is operable to be secured to one of a plurality of mounting plates to secure and present the latch core to the striker. The plurality of mounting plates may include (a) a mounting plate for a lift gate latch, (b) a mounting plate for a decklid latch, and (c) a mounting plate for a sliding door latch. The latch core is further operable to mount any one of a plurality of latch modules, including a manual release latch module, a power release latch module, a power lock and unlock latch module, and a power cinching and release latch module. 
     In another aspect of the invention there is a latch for an automotive vehicle. It has a latch core. The latch core has a housing and a ratchet and pawl rotatably mounted to the housing. The ratchet and pawl are co-operable to move between an engaged position to hold a striker and a released position. The latch core has securement fittings attachable to any one of a plurality of mounting plates of a set of mounting plates for securing the latch core to a vehicle in a position to present the latch core to the striker. The set of mounting plates includes: a mounting plate for a lift gate latch, a mounting plate for a decklid latch, and a mounting plate for a sliding door latch. The latch core has operational connections attachable to at least one other latch module of a set of other latch modules. That set includes: a manual release latch module, a power release latch module, a power lock and unlock latch module, and a power cinching and release latch module. 
     In a feature of that aspect of the invention, the core latch further includes a cover plate mounted to the housing, and a channel for receiving a striker defined in each of the mounting plate, the housing and the cover plate. The ratchet and pawl are cooperable to move between a primary engagement position to hold the striker in the channel, a secondary engagement position to hold the striker in the channel, and a released position to permit the striker to exit the channel. The ratchet and pawl are biased toward the primary and secondary engagement positions. The pawl is pivotable about a pawl axis. A secondary pawl is pivotally mounted to the housing on an axis offset from the pawl axis. The secondary pawl is kinematically coupled at a first end to the pawl, and has an out-of-plane tab mounted to drive the pawl. The secondary pawl is mounted to drive the pawl in a rotational direction opposite to the pawl. 
     In another aspect of the invention there is a latch for an automotive vehicle. It has a housing and a ratchet and pawl pair. The ratchet and pawl are rotatably mounted to the housing and are co-operable to move between a mutually engaged position for holding a striker and a released position. There is a secondary pawl, rotatably mounted to the housing and operable to actuate the pawl to release the ratchet. The pawl and secondary pawl each have a center of rotation and a center of gravity. The centers of rotation and centers of gravity are substantially coincident for the pawl and the secondary pawl respectively. 
     In a further aspect of the invention there is an automobile latch core for mounting between an outside enclosure member and an inside backing plate in a mechanical sandwich having a fishmouth for admitting a matably engageable striker. The latch core includes a substrate; a ratchet and ratchet biasing member; a pawl and pawl biasing member; and at least a first status sensor member and an associated first status sensor switch. The substrate has accommodations for the ratchet, the ratchet biasing member, the pawl and the pawl biasing member, and for the first status sensor member and the first status sensor switch. The latch core has a fishmouth. The latch core has an inner end of the fishmouth having cinched striker center position. Excluding indexing protrusions and fishmouth wear members, the latch core has a predominant width, W, longitudinally endwardly of the cinched striker center position, a length L from the striker center position to the fishmouth end, and a through thickness t between the outside enclosure member and the backing plate wherein W is less than 65 mm, L is less than 35 mm, and t is less than 20 mm. 
     In a further feature of that aspect of the invention, (a) W is less than 60 mm; (b) L is less than 32 mm; and t is less than 16 mm. In a still further feature, (a) W is less than 60 mm; (b) L is less than 32 mm; and (c) t is less than 16 mm. In a yet further feature, W is in the range of 50-55 mm; L is in the range of 25-32 mm; and t is less than 15 mm. 
     In another aspect of the invention there is a method of operating a latch for an automobile, the latch having a housing having a slot for receiving a striker, a cooperating ratchet and pawl pair mounted to the housing, and at least one sensor and sensor switch pair mounted to the housing, wherein the method includes using the sensor to check directly for the presence of a striker in the slot, and driving the ratchet to cinch the striker when there is a signal that the striker is present in the slot. 
     In still another aspect of the invention there is a latch for an automobile, the latch having a housing having a slot for receiving a striker, a co-operating ratchet and pawl pair mounted to the housing, and at least one sensor and sensor switch pair mounted to the housing, the sensor being mounted to monitor directly for the presence of a striker in the slot, and the latch is operable to drive the ratchet to cinch the striker in response to a signal from the switch that the striker is present in the slot. 
     In a further feature of that aspect, the latch has both a first sensor member and a second sensor member monitoring for the presence of a striker in the slot. In another feature, the first sensor member monitors for striker presence in at least an entrance portion of the slot, and the second sensor member monitors for striker presence in at least an innermost portion of the slot distant from the entrance portion. 
     In still yet another aspect of the invention, there is a latch core substrate for a latch assembly of an automobile. The substrate is formed of a molded monolith. The substrate includes accommodations for at least a ratchet, a pawl, a first status sensor member, and an associated first status sensor switch. The substrate includes an integrally formed movable member interposed between the accommodation for the first status sensor switch and the first status sensor member. The movable member is positioned to be acted upon by the first status sensor member; and the movable member is positioned to act upon the first status sensor switch when acted upon by the first status sensor member. 
     In a still further aspect of the invention, there is a latch core substrate for a latch assembly of an automobile. The substrate is formed of a molded monolith having a striker motion accommodating slot defined therein. The substrate includes accommodations for at least a ratchet, a pawl, a first status sensor member, and an associated first status sensor switch. The substrate includes a first fitting array defining a first latch core layer, the first latch core layer including the accommodations for the ratchet and the pawl. The substrate includes a second fitting array defining a second latch core layer, and the second latch core layer includes the accommodation for the first status sensor member. 
     In a further feature, the substrate includes fittings defining a third latch core layer. In another feature, the third layer has fittings defining a snowload lever seat. In another feature, the substrate includes communication passages between at least two of the layers. 
     In still another feature, there is a latch core for a latch assembly of an automobile, the latch core including the aforesaid substrate, a ratchet, a pawl, a first status sensor member, and an associated first status sensor switch each seated in its respective accommodation. The first status sensor member being operable to sweep through a range of motion, the range of motion overlapping at least part of the striker motion accommodating slot. The first status sensor member being operable independently of the ratchet. The first status sensor member is operable independently of the pawl. 
     In another aspect of the invention there is a latch for an automobile. The latch has a housing having a slot for receiving a striker; a co-operating ratchet and pawl pair mounted to the housing; a first sensor and associated first sensor switch mounted to the housing; and a second sensor and associated second sensor switch mounted to the housing. The first sensor is mounted to obstruct the slot, and is movable from the slot by the striker, the first switch being operably connected to change state on movement of the first sensor. The second sensor being a pawl position monitoring sensor. 
     In a feature of that aspect, no sensor of the latch is connected to monitor ratchet position. In another feature, there is a method of operating the latch, that includes (a) monitoring for a change of state of the first switch to signify the presence of a striker in the slot; (b) monitoring the second switch for the presence of a state associated with the presence of a bias of the pawl to engage the ratchet and prevent opening movement thereof; and (c) driving the ratchet toward the closed position when conditions (a) and (b) are satisfied. In another feature there is a method of releasing the latch including driving the pawl release to a release position; polling the first switch for a change in state signifying outward motion of the striker; polling the second switch for a change of state signifying arrival of the striker at a fully released state. 
     In another aspect of the invention there is a latch core for a latch assembly of an automobile. The latch core has a mounting substrate having a striker motion accommodating slot formed therein; a ratchet, a pawl, a first status sensor member, and an associated co-operable first status sensor switch each seated in a respective accommodation of the mounting substrate. The first status sensor member is operable to sweep through a range of motion that overlaps at least part of the striker motion accommodating slot. The first status sensor member is operable independently of the ratchet and independently of the pawl. 
     The various aspects of the invention may also include the use, or methods of use of the apparatus shown, described, or claimed herein. These and other aspects and features of the invention may be understood with reference to the description which follows, and with the aid of the illustrations of a number of examples. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The description is accompanied by a set of illustrative Figures in which: 
         FIGS. 1 a  and 1 b    provide tables showing a prior art switching strategies; 
         FIG. 2  shows a modular latch having multiple configurations in accordance with a first aspect of the invention; 
         FIG. 3  shows a perspective view of a latch core used in the modular latches shown in  FIG. 2 ; 
         FIG. 4  shows a top plan view of the latch core shown in  FIG. 3 , having the latch plate removed; 
         FIG. 5  shows a bottom plan view of the latch core shown in  FIG. 3 , having the latch plate removed; 
         FIG. 6  is a detailed exploded view of the latch core components shown in  FIG. 3 ; 
         FIG. 7  shows an isolated view of a pawl and secondary pawl for the latch core shown in  FIG. 3 ; 
         FIG. 8 a    shows a manual release module mounted to the latch core of  FIG. 3 ; 
         FIG. 8 b    shows a power release module mounted to the latch core of  FIG. 3 ; 
         FIG. 9  is a side plan view for a power release module for the modular latch of  FIG. 2 ; 
         FIG. 10  is a side plan view for a power locking and unlocking module for the modular latch shown in  FIG. 2 ; 
         FIG. 11 a    is a side plan view for the power release module shown in  FIG. 10 , while locked and with the release lever at rest; 
         FIG. 11 b    is a side plan view for the power release module shown in  FIG. 10 , while locked and with the release lever actuated; 
         FIG. 11 e    is a side plan view for the power release module shown in  FIG. 10 , while unlocked and with the release lever at rest; 
         FIG. 11 d    is a side plan view for the power release module shown in  FIG. 10  while unlocked and with the release lever actuated in order to release the latch; 
         FIG. 12  is an exploded view for a power cinching and release module for the modular latch shown in  FIG. 2 ; 
         FIG. 13  is a perspective view for the power cinching and release module for the modular latch shown in  FIG. 12 ; 
         FIG. 14  is a side plan view for a power cinching and release module in the resting position for the modular latch shown in  FIG. 12 ; 
         FIG. 15 a    is a side plan view for a power cinching and release module in the cinched position for the modular latch shown in  FIG. 12 ; 
         FIG. 15 b    is a side plan view for a power cinching and release module in the power release position for the modular latch shown in  FIG. 12 ; 
         FIG. 16  shows an isolated view of a power-cinching ratchet for the latch core shown in  FIG. 12 ; 
         FIG. 17  is a side plan view for a power cinching and release module in the manual reset position for the modular latch shown in  FIG. 12 ; 
         FIG. 18 a    shows a top plan view of the latch core shown in  FIG. 3 , featuring a striker switching assembly in the resting position; 
         FIG. 18 b    shows a top plan view of the latch core shown in  FIG. 3 , featuring a striker switching assembly in the actuated position; 
         FIG. 19 a    shows a top plan view of the latch core shown in  FIG. 3 , featuring a striker entering a latch having the ratchet in the released position; 
         FIG. 19 b    shows a top plan view of the latch core shown in  FIG. 3 , featuring a striker entering a latch having the ratchet in between the primary and secondary engagement positions; 
         FIG. 19 c    shows a top plan view of the latch core shown in  FIG. 3 , featuring a striker entering a latch having the ratchet moving towards the primary engagement position; 
         FIG. 19 d    shows a top plan view of the latch core shown in  FIG. 3 , featuring a striker entering a latch having the ratchet in the primary engagement position; 
         FIG. 20  shows a table presenting a switching strategy in accordance with an aspect of the invention; 
         FIG. 21 a    shows the bottom plan view of the latch core shown in  FIG. 3 , having a snowload assembly in the resting position; 
         FIG. 21 b    shows the bottom plan view of the latch core shown in  FIG. 3 , having a snowload assembly in the engaged position; 
         FIG. 21 c    shows the bottom plan view of the latch core shown in  FIG. 3 , having a snowload assembly being manually reset; 
         FIG. 21 d    shows the bottom plan view of the latch core shown in  FIG. 3 , having a snowload assembly where the ratchet has been released position; 
         FIG. 22 a    shows an exploded view of an alternate door latch assembly to that of  FIG. 3 ; 
         FIG. 22 b    is an assembled isometric view of the door latch assembly of  FIG. 22   a;    
         FIG. 22 c    shows a side view of the latch assembly of  FIG. 22   a;    
         FIG. 22 d    shows a view of the latch assembly of  FIG. 22 a    taken on arrow ‘ 22   d ’ of  FIG. 22 c    with the top backing plate removed to expose the latch core; 
         FIG. 22 e    shows the latch assembly of  FIG. 22 d    with the internal housing plate also removed; 
         FIG. 22 f    shows the latch core of  FIG. 22 d    from the underside; 
         FIG. 22 g    is a section of the latch assembly of  FIG. 22 d    taken on ‘ 22   g - 22   g’;    
         FIG. 22 h    is a section of the latch assembly of  FIG. 22 d    taken on ‘ 22   h - 22   h’;    
         FIG. 22 i    is an enlargement of  FIG. 22   f;    
         FIG. 23 a    is an isometric view of an alternate embodiment of latch assembly to that of  FIG. 22 a   , having a power cinching input; 
         FIG. 23 b    is a side view of the latch assembly of  FIG. 23   a;    
         FIG. 23 c    is a top view of the latch assembly of  FIG. 23 b    taken on arrow ‘ 23   c’;    
         FIG. 23 d    shows the latch assembly of  FIG. 23 c    with the top cover back plate removed to reveal the latch core; 
         FIG. 23 e    shows the latch assembly of  FIG. 23 d    on section ‘ 23   e - 23   e’;    
         FIG. 23 f    shows the latch assembly of  FIG. 23 d    on section ‘ 23   f - 23   f’;    
         FIG. 23 g    shows an end view of the latch assembly of  FIG. 23   a;    
         FIG. 23 h    shows the latch core of  FIG. 23 d    from the underside; 
         FIG. 24 a    is a top isometric view of a latch core housing common to the latch cores of  FIG. 22 i    and  FIG. 23   g;    
         FIG. 24 b    is a bottom isometric view of a latch core housing common to the latch cores of  FIG. 22 i    and  FIG. 23   g;    
         FIG. 24 c    is a top plan view of the latch core housing of  FIG. 24   a;    
         FIG. 24 d    is a bottom plan view of the latch core housing of  FIG. 24   a;    
         FIG. 24 e    is a side view of the latch core of  FIG. 24   a;    
         FIG. 25 a    shows the latch core of  FIG. 24 a    in a “secondary” position at the initiation of power cinching; 
         FIG. 25 b    shows the latch core of  FIG. 25 a    in a first cinching position; 
         FIG. 25 c    shows the latch core of  FIG. 25 a    in a second cinching position; 
         FIG. 25 d    shows the latch core of  FIG. 25 a    in a fully cinched position; 
         FIG. 26 a    shows a logic chart for cinching of the latch core of  FIG. 25 a   ; and 
         FIG. 26 b    shows a logic chart for the release cycle of the latch core of  FIG. 25   a.    
     
    
    
     DETAILED DESCRIPTION 
     The description that follows and the embodiments described therein are provided by way of illustration of an example, or examples, of particular embodiments of the principles, aspects or features of the present invention. These examples are provided for the purposes of explanation, and not of limitation, of those principles and of the invention. In the description, like parts are marked throughout the specification and the drawings with the same respective reference numerals. The drawings are generally to scale unless noted otherwise, although the scale may differ from drawing to drawing. Reference to directions such as up and down, front and back, left and right, top and bottom, may tend to be arbitrary, and these terms may be used for convenience rather than to define a required orientation, unless noted otherwise. The terminology used in this specification is thought to be consistent with the customary and ordinary meanings of those terms as they would be understood by a person of ordinary skill in the automobile industry in North America. The Applicant expressly excludes all interpretations that are inconsistent with this specification. 
       FIG. 2 , shows an array, or matrix, of combinations of latch assembly modules such as may be mixed and matched to arrive at a latch suitable for any of a range of employments. In  FIG. 2 , a latch module is shown generally at  10 . Modular latch  10  is adapted to receive a striker from a number of different closure panels, including a liftgate, a decklid or a sliding door (none shown). Modular latch  10  can be employed in a number of different configurations, including a liftgate latch  10   a , a decklid latch  10   b  and a sliding door latch  10   c . References made to modular latch  10 , as opposed to latch  10   a ,  10   b  or  10   c  describe features held in common between all different configurations of modular latch  10 . Each different configuration of modular latch  10  includes a common latch core  12  that is the same for all configurations. Latch core  12  is described in greater detail below. 
     A specially-adapted mounting plate  14  is used to mount latch core  12  to the vehicle. Mounting plate  14  is used for the liftgate latch  10   a , mounting plate  14   b  is used for the decklid latch  10   b , and mounting plate  14   c  is used for the sliding door latch  10   c . References made to mounting plate  14 , as opposed to mounting plate  14   a ,  14   b  or  14   c  describe features held in common between all different configurations of mounting plate  14 . Mounting plate  14  may be a stamped metal component that includes the required flanges and fastener holes to mount it to the vehicle body, and is shaped to present the latch core  12  to a striker (not shown) to secure the latch. A latch module  16  is mounted to the latch core  12  for all of the different configurations of modular latch  10 . Additionally, there a number of different latch modules that each provide a specific functionality to the various latch configurations. Latch module  16   a  provides for manual release of latch  10  only. Latch module  16   b  provides for both power release and manual release of latch  10 . Latch module  16   c  adds power locking and unlocking to the functionality of latch module  16   a . Latch module  16   d  adds power cinching and release to the features described above. The various types of latch modules  16  will be described in greater detail below. 
     Latch core  12  is shown in greater detail in  FIGS. 3 to 6 . Latch core  12  includes a housing  18  that houses the latch core components, and retains them in place during normal operation and shipment. Housing  18  may be formed of a molded thermoplastic material. Housing  18  includes a substrate  20  that, when secured to the mounting plate  14 , is generally parallel to substrate  22  found on the mounting plate  14  ( FIG. 8 a   ). A sidewall portion  24  runs partially along the edges of substrate  20 . Mounting posts  26  extend from substrate  20 , and are sized as to fit within apertures  27  in mounting plate  14 , thereby locating core latch  12  on mounting plate  14  ( FIG. 9 ). As will be described in greater detail below, the ratchet and pawl assembly fastens latch core  12  to mounting plate  14 . 
     A compartment  28  is formed between housing  18 , and sidewalls  19  and substrate  22  of mounting plate  14  to house various latch components. A ratchet  30  and pawl  32  are mounted within compartment  28 . Ratchet  30  and pawl  32  may be made of metal, which may be covered with, or encapsulated in a plastic material to some extent to reduce noise during operation. Certain portions subject to wear, such as the ratchet teeth are not covered by plastic. A tapering channel, referred to as a “fishmouth”  34  bisects substrate  22 . In operation, fishmouth  34  receives a striker  35  ( FIG. 9 ), which engages a hook arm  36  of ratchet  30 . An end-of travel, elasometric or rubber overslam bumper  38  is mounted at the inner end of fishmouth  34 . Bumper  38  receives and absorbs the impact of the striker  35 , and may tend to reducing noise. 
     Ratchet  30  is pivotally secured to substrate  20  by a ratchet rivet  42  inserted into aligned holes provided in substrates  20 ,  22  and ratchet  30 . Ratchet  30  is pivotable between a “primary engagement”, or fully clinched, position ( FIG. 19 d   ), where a primary tooth  31  of ratchet  30  is retained by pawl  32 ; a “secondary engagement” position, where a secondary tooth  36  of ratchet  30  is retained by pawl  32  ( FIG. 19 b   ), and a “released” position ( FIG. 19 a   ). When a striker  35  enters fishmouth  34 , it engages hook arm  36 , thereby rotating ratchet  30  towards the primary engagement position. A ratchet spring  50  urges ratchet  30  towards the released position. Rotating ratchet  30  towards the engagements positions compresses ratchet spring  50 . 
     Pawl  32  is pivotally mounted to substrate  20  by a pawl rivet  52  inserted into aligned holes in substrates  20 ,  22 , and pawl  32 . Pawl  32  is movable between an “engaged” position where it abuts either primary tooth  31  ( FIG. 19 d   ) or secondary tooth  36  ( FIG. 19 b   ) on ratchet  30 , and a released position ( 19   a ), where it is rotated away from ratchet  30  to permit ratchet  30  to rotate towards its released position. When ratchet  30  is in its released position, pawl  32  is retained in the engaged position by secondary pawl  60  and secondary pawl bumper. A ratchet shoulder  56  on pawl  32  abuts either primary tooth  31  on ratchet  30  or secondary tooth  36  when ratchet  30  is in its primary or secondary engagement positions, respectively, preventing ratchet  30  from rotating towards the released position. A pawl spring  58 , mounted around pawl rivet  52  urges pawl  32  towards the engaged position. Rotating pawl  32  to the released position compresses pawl spring  58 . 
     A secondary pawl  60  is pivotally mounted the side of housing  18  opposite substrate  20  along axle  62 . A first end  64  of secondary pawl  60  is kinematically coupled with pawl  32  within an aperture  65  in housing  18  ( FIG. 5 ), so that pivoting one of pawl  32  and secondary pawl  60  pivots the other in the opposing direction. A second end  66  of secondary pawl  60  includes a depending tab  68  which extends through a slot  70  in an auxiliary cover plate (described below) which can be actuated by a release lever (also described below). A tab  72  depends from pawl  32 , extends through aperture  65 , and is fitted into a socket  74  on the first end  64  of secondary pawl  60 , kinematically coupling pawl  32  and secondary pawl  60  together. The effective center of gravity of the combined pawl  32  and secondary pawl  60  is also the effective center of rotation for the coupled pawls. Thus, there are no inertial events acting on either of pawl  32  or secondary pawl  60  during a sudden deceleration (i.e., a crash) to cause pawl  32  to actuate ratchet  30 , thereby reducing the chances of the latch  10  accidentally releasing. 
     Referring now to  FIGS. 3, 8   a ,  8   b  and  9 , a cover plate  76  is provided on the side of housing  18  opposite compartment  28 . Cover plate  76  may be a metal stamping. Cover plate  76  is secured to housing  18  primarily by ratchet rivet  42  and pawl rivet  52 . Additional fasteners may also be used. Cover plate  76  includes a substrate  78  that is generally parallel to substrates  20  and  22 , and a sidewall  80  that runs generally perpendicular to substrate  78 . When core latch  12  is attached to mounting plate  14 , sidewall  80  abuts mounting plate  14 . Sidewall  80  has edge tabs  82 . Tabs  82  extend through a slot  84  on mounting plate  14 .  FIG. 5  illustrates a compartment  86  formed between cover plate  76  and housing  18 , opposite compartment  28 . As noted, secondary pawl  60  is housed within compartment  86 . 
     As noted above, latch module  16  is mounted to latch core  12  to provide release, power locking or cinching functionality, or all of them.  FIGS. 8 to 15  illustrate three different latch modules,  16   a ,  16   b  and  16   c  in various states of operation. Each latch module  16  includes a base adapter or brain plate  100 . The shape of brain plate  100  may vary due to the hardware mounted thereon, but each includes standardized mounting components to allow the different latch modules  16  to be mounted to the common latch core  12 . Brain plate  100  may be made of plastic to reduce cost and weight. Each brain plate  100  includes a mounting flange  102  that sits against sidewall  80  on cover plate  76 . Along mounting flange  102 , there is a pair of anchoring hooks  104 . One anchoring hook  104  ( FIG. 3 ) is inserted through slot  106  along the edge of cover plate  76 , and the other anchoring hook  104  is inserted into slot  106  with the surface of cover plate  76  ( FIG. 3 ). A fastener  108  extends through aligned apertures  110  in mounting flange  102  and side wall  80  of cover plate  76 . Once slid into place, anchoring hooks  104 , and fastener  108  provide a tight fit, holding latch module  16  in place. This mounting arrangement transfers the load from plastic latch module  16  to metal cover plate  76 . Optional fastener apertures  112  can be provided in both brain plate  100  and cover plate  76  for additional fasteners, if desired. 
       FIG. 8  shows a manually released latch module  16   a , and  FIGS. 8 b    and  9  show a power-release latch module  16   b . A release lever  120  is pivotally mounted to a first side  118  of brain plate  100 , and is movable between a “resting” position (seen in  FIG. 9 ) and an “actuated position”, where a lever arm  121  engages depending tab  68  on secondary pawl  60 , thereby actuating pawl  32  to release latch  10 . Release lever  120  pivots around an integrally-formed fixed axle  122  that is seated within an aperture  124 . A pair of wings  126  extend out radially from axle  122 , and aperture  124  includes a pair of wing-shaped cutouts  128  to permit insertion and subsequent retention of release lever  120 , without the use of separate fasteners. A spring  130  biases release lever  120  towards the resting position, and is mounted around fixed axle  122 . A first arm  132  is located within a slot  134  on release lever  120 , and a second arm  136  is located within a slot  138  on brain plate  100 . A bumper  140  is proved along a first end  142  of release lever  120 , and which abuts against a sidewall  144  on brain plate  100  when the release lever  120  is in the resting position. A second end  146  of release lever is adapted to mount a release cable  148  for manual actuation. Pulling release cable  148  pivots release lever  120  to the actuated position to release latch  10 , and further loads spring  130 . Once tension is released on cable  148 , spring  130  returns release lever  120  to the resting position. 
     Latch module  16   b  includes all the features described above for latch module  16   a , in addition to the following. An actuator  150  is mounted to a second side  151  of brain plate  100 . Actuator  150  is electrically connected to the vehicle&#39;s power supply (not shown), and drives an orbital cam  152 , which extends through an aperture  154  ( FIG. 8 a   ) in brain plate  100  to first side  118 . The rotational path of orbital cam  152  intersects the second end  146  of release lever  120 , when in the resting position, thereby moving release  1  ever  120  to the actuated position. Once release lever  120  is in the actuated position, the latch  10  releases and the switch (described below) in core latch  12  sends the signal to the door controller in the vehicle (not shown) to stop actuator  150 . As the actuator motor stops, actuator  150  back-drives, rotating orbital cam  152  in the opposite direction of actuation and comes back to the resting position. Since the release lever  120  is spring loaded against orbital cam  152 , therefore, as the orbital cam  152  rotates back to the rest position the release lever also follows the orbital cam and returns back to rest position. 
     Referring now to  FIGS. 10, and 11   a  to  11   d , a latch module  16   c , which provides for power locking and unlocking is shown in greater detail.  FIG. 11 a    corresponds to latch module  16   c  being locked, with the release handle at rest.  FIG. 11 b    corresponds to latch module  16   c  being locked, with the release handle actuated.  FIG. 11 c    corresponds to latch module  16   c  being unlocked, with the release handle at rest, and  FIG. 11 a    corresponds to latch module  16   c  being unlocked, with the release handle actuated to release the latch. 
     Latch module  16   c  includes all the features of latch modules  16   a , in addition to the following features described below. With latch module  16   c , release lever  120  is replaced with release lever  120   c  and auxiliary release lever  160 , which is pivotally and coaxially mounted around axle  122  on release lever  120   c . Auxiliary release lever  160  is operable to actuate the depending tab  68  on secondary pawl  60 . A lock and unlock lever  162  acts as the lock and unlock output shaft of the actuator  150   c . Actuator  150   c  includes a reversible DC motor, and engaging actuator  150   c  moves locking lever  162  between a locked position ( FIG. 11 a    and unlocked position ( FIG. 11 c   ). A second end  168  of locking lever  162  is adapted to receive a lock cable  170  for manual locking and unlocking ( FIG. 10 ). A pin  172  extends through a slot  174  in locking lever  162 , slot  176  in auxiliary release lever  160 , and also in an L-shaped slot  178  in release lever  120   c . Moving locking lever  162  into the unlocked position ( FIG. 11 c   ) slides pin  172  into an arm  180  of L-shaped slot  178  (best seen in  FIG. 11 b   ), thereby kinematically coupling release lever  120   c  and auxiliary release lever  160 . Thus, actuating release lever  120   c  also actuates auxiliary release lever  160  to engage secondary pawl  60 . Moving locking lever  162  into the locked position moves pin  172  into arm  182  of L-shaped slot  178 , thereby kinematically decoupling release lever  120   c  and auxiliary release lever  160 . Thus, actuating release lever  120 C does not actuate auxiliary release lever  160 . A spring  184  that is located around a post  186  in brain plate  100 , and has an arm  187  hooked into locking lever  162  biases locking lever  162  towards the nearest of locked and unlocked positions. 
     Referring now to  FIGS. 12-17 , a latch module  16   d , which provides for power cinching and releasing is shown in greater detail.  FIG. 12  shows an exploded view of latch module  16   d  with the brain plate  100   d  removed.  FIG. 13  shows a perspective view of the front of latch module  16   d , including brain plate  100   d .  FIG. 14  shows latch module  16   d  in a resting state. Latch module  16   d  includes an actuator  150   d , having a spur  200  mesh with the teeth on a sector gear  202  on the opposite side of brain plate  100   d . Sector gear  202  rotates on an axle  203  between a resting position ( FIG. 14 ), a cinched position ( FIG. 15 a   ), and a power release position ( FIG. 15 b   ). Once the cinch and the release operation is complete as required, the switches in the latch send the signal to the door controller in the vehicle which powers the actuator in the opposite direction to the operation last performed which brings the sector and the complete gear train back to the home or resting position. 
     A sector arm  211  is coaxially mounted over sector gear  202  on axle  203  and operable to pivot independently of sector gear  202 . A pin  212  extends through a slot  213  in sector gear  202  and a straight slot  214  in sector arm  211 . Slot  213  in sector gear  202  has a generally arcuate portion  213   a , and a leg portion  213   b  that extends outwards. A spring  215 , mounted around a post  216  on sector arm  211  biases pin  212  to sit leg portion  213   b . Thus, under normal operating conditions, the rotational movements of sector gear  202  and sector arm  211  are coupled, and the two pivot together in tandem. 
     Latch module  16   d  uses a four-bar cinching assembly to transfer the loading force from sector gear  202  to ratchet  30 . As is best seen in  FIG. 16 , when sector gear  202  moves to the cinched position ( FIG. 15 a   ), sector arm  211  pivots a cinch lever  217  from a “resting” position ( FIG. 15 b   ) to a “cinched” position ( FIG. 15 a   ). Referring to  FIG. 16 , cinch lever  217  is fixedly mounted to a cinch axle  218  that is rotatably mounted within core latch  12 . A cam arm  219  is fixedly mounted around cinch axle  218 . A link  220  is pivotally attached at a first end  222  to cam arm  219 , and at a second end  224  to ratchet  30 . Rotating cinch lever  217  rotates ratchet  30  in an opposite direction. Thus, rotating sector gear  202  to the cinched position rotates ratchet  30  to its engaged position. Cinch lever  217 , cam arm  219 , link  220  and ratchet  30  form a four-bar assembly that ensures the input load provided by actuator  150   d  remains steady while the output rotational load of ratchet  30  matches the resistance load profile of the gate or door being cinched (generally an exponential profile). By varying the lengths of the different components of the four-bar mechanism, different resistance load profiles can be achieved. A spring  224  is coiled around cinch axle  218  (see  FIGS. 18 a  and 18 b   ). Spring  224  has a pair of arms  225  that are located in slots  227  in housing  18 , and which prevent spring  224  from rotating. Thus rotating cinch axle  218  tightens the spring  224  around the axle so that when ratchet  30  is engaged, spring  224  returns cinch lever  217  and four-bar mechanism to its resting position. 
     In  FIG. 15 b   , power release is provided by reversibly engaging actuator  150   d , which rotates sector gear  202  and sector arm  211  in the opposite direction (in the illustrated embodiment, sector gear  202  rotates counter clockwise). Sector arm  211  engages a tab  228   a  on an auxiliary release lever  230 , which is pivotally mounted to a portion of brain plate  100  that is substantially parallel to substrate  78  on cover plate  76 . An arm  232  on auxiliary release lever  230  pivots and actuates depending tab  76  on secondary pawl  60  to actuate secondary pawl  60 , and releases the latch. A spring  233  is mounted around a post  234 , which biases auxiliary release lever  230  to a resting position away from tab  232  of secondary pawl  60 . Once the release operation is complete, the switches in the latch send the signal to the door controller in the vehicle which powers the actuator in the opposite direction to the release direction and brings the sector and the complete gear train back to the home, or resting, position. 
     Manual release is provided by actuating the release cable  146   d , which pivots release lever  120   d . A tab  226  on release lever  120   d  abuts against a tab  228   b  on an auxiliary release lever  230 , which then actuates the depending tab  68  on secondary pawl  60  to release the latch. As release cable  146  returns to its resting position, release lever  230  returns to its resting position, with tab  226  located between tabs  228   a  and  228   b  under the load from auxiliary release lever  230  and spring  233 . 
     Electrical power may fail during a power cinch or power release actuation, leaving sector gear  202  out of its resting position, and ratchet  30  located midway between positions—potentially hindering future operation of the latch. To prevent this, a reset function is provided by manually engaging release lever  120   d . Referring now to  FIG. 17 , a reset lever  235  is pivotally mounted around a post  236  on sector arm  211 , and rests against pin  212 . During normal power operations, reset lever  235  remains in place, rotating around axle  203  with sector arm  211 . However, when release lever  120   d  is pivoted for manual release, an arm  237  on the lever engages the reset lever  235 , pivoting it downwards. As reset lever  235  pivots, it forces pin  212  down from slot  213   b  into slot  213   b  ( FIG. 12 ). With pin  212  in slot  213   a , sector gear  202  and sector arm  211  are decoupled. Thus sector arm  211  can return to its resting position without needing to backdrive actuator  150   d . Once release lever  120   d  is released, a spring  238 , mounted on a post  239  on brain plate  100   d  returns sector arm  211  to the correct resting position relative to sector gear  202 . Pin  212  moves back along arcuate slot  213   a  to a position under slot  213   b . Spring  215  then returns pin  212  to slot  213   b , re-coupling sector gear  202  and sector arm  211  once the latch is powered again. A return spring  204  is mounted to a post  206  of brain plate  100   d , and has an arm  208  that extends to bias sector gear  202  to its return, or at rest, position. Tail end  210  of spring  204  is anchored to brain plate  100   d.    
     For power cinching and release, the actuator needs to know the location of the striker  35  within the fishmouth  34 , position of the ratchet (i.e., primary engagement, secondary engagement, or release position) and pawl (engaged or disengaged), in order to know when to start, and how long to drive actuator  150   d . Typical prior art latches used a switch that is triggered by the pivotal movement of the ratchet (either on an external edge of the ratchet, or on a linked axial cam), to indicate that the striker is engaged and that power cinching should begin (as shown in  FIGS. 1 a  and 1 b   ). In other words, the switch indicated only when the ratchet was closing, not whether striker  35  was located within the fishmouth. This limitation could lead to scenarios where the gate was resting on the striker  35 , but not actually being held in place by the ratchet. In contrast, the present switching strategy reports on the position of the striker  35  directly. 
     Referring now to  FIGS. 18 a  and 18 b   , a portion of common latch  12  is shown in greater detail. A striker lever  240  is pivotally mounted around an axle  242  that is located within housing  18 . Striker lever  240  is movable between a resting position ( FIG. 18 a   ), where a first end  244  extends into fishmouth  34 , and an actuated position ( FIG. 18 b   ), where first end  244  is rotated out of fishmouth  34  by the striker  35  ( FIGS. 19 b -19 b   ). A spring  246 , that is mounted around a post  247  biases striker lever  240  towards the resting position. Thus, as soon as a striker  35  enters fishmouth  34 , striker lever  240  moves to the actuated position, and as soon as it is withdrawn, striker lever  240  moves to the released position. A switch arm  248  on striker lever  240  triggers a striker switch  250  that is mounted within core latch  12 . When striker lever  240  is in the resting position, switch arm  248  engages a striker switch  250  (ON state). When striker lever  240  is rotated to the actuated position, switch arm  248  rotates away from switch  250 , disengaging it (OFF state). It will thus be apparent that striker switch  250  detects the presence or absence of striker  35  within fishmouth  34  (as can be seen in the switch strategy table in  FIG. 20 ). 
     An ajar switch  252  is also provided within core latch  12 . Ajar switch  252  is actuated by a switch arm  254  on secondary pawl  60  ( FIG. 6 ). When secondary pawl  60  is resting, switch arm  254  is displaced away from ajar switch  252 . When secondary pawl  60  is actuated, switch arm  254  engages ajar switch  252 . In addition, a striker ajar lever  256  is also used engage ajar switch  252  via a switch arm  257 . Striker ajar lever  256  also has an ajar arm  258  extending into fishmouth  34 , although not as far as striker lever  240 . Thus, striker ajar lever  256  is pivoted by striker  35  much closer to the primary engagement position than striker lever  240 . Striker ajar lever  256  is pivotally mounted around an axle  260  in substrate  20 , and pivots between an engaged position ( FIG. 19 a , 19 b   ) where it engages ajar switch  252 , and a disengaged position ( FIG. 19 c , 19 d   ), where it is disengaged with ajar switch  252 . In order to eliminate the transition zone of ajar switch  252 , switch arm  257  on striker ajar lever  256  and switch arm  254  on secondary pawl  60  move in parallel, overlapping paths (best seen in  FIG. 6 ). In order to minimize slippage off the switch blade, a living blade  262  is formed from substrate  20  that extends into compartment  28  so that it can abut against either of switch arms  254  and  257 . Living blade  262  is molded thin enough as to provide a resilient blade that can be moved by either switch arm to trigger switch  252 . Living blade  262  is sized as to provide a larger engagement profile than ajar switch  252 . 
     Switch arm  254  on secondary pawl  60 , by itself, will provide a control logic identical to the prior art pawl switch described in  FIG. 1 . Namely, it shows an ON state while the ratchet is open. When the ratchet  30  moves to the secondary engagement position, it disengages from ajar switch  252 , briefly re-engages as the ratchet  30  moves from the secondary engagement position to the primary engagement position, where it disengages once again. However, when combined with switch actuation provided by striker ajar lever  256 , the state of ajar switch  252  matches the switching strategy described in  FIG. 20 . Ajar switch  252  is in the ON position while the ratchet moves from the Open position to the secondary engagement position. Striker ajar lever  256  maintains ajar switch  252  in the ON position even as the pawl  32  disengages and moves between secondary and primary engagement positions. Finally, as striker  35  reaches overslam bumper  38  at the end of fishmouth  35 , it actuates striker ajar lever  256  to release striker switch  252 , just as the ratchet is entering the primary engagement position. With both striker arm  254  of secondary pawl and switch arm  257  displaced away from ajar switch  252 , it switches to the OFF state. 
     The switching strategy described herein may tend to avoid problems found in earlier latches. Unlike the switching strategy of  FIG. 1 a   , there is no indeterminate condition caused when the ratchet moves between the secondary engagement position and the primary engagement position. Furthermore, the actuator knows exactly how long to apply cinching power, unlike the switching strategy described in  FIG. 1 b   . Striker switch  250  moves to the OFF state when the striker  35  enters fishmouth  34  this provides the indication to activate the actuator  150   d . Ajar switch  252  switches to OFF when ratchet  30  moves into the primary engagement position. Thus, the actuator  150   d  turns on at the correct moment, and off at the correct movement, with minimal overlap. Furthermore, this switching strategy is more robust and easier to implement than prior art switching strategies. 
     Referring back to  FIG. 15 a   , an optional sector switch  261  is mounted into brain plate  100   d . For power cinching modules  16   d  that do include a sector switch  261 , a switch lever  263  is pivotally mounted around a post  265  in brain plate  100   d , and is operable to engage or disengage sector switch  261 . A spring  267 , mounted around a post  269  in brain plate  100   d  biases switch lever  263  to engage switch  261 . The rotation of sector gear  202  out of its resting position moves switch lever  263  to disengage from sector switch  261 . The electronic control unit in the vehicle (not shown) can simply reverse actuator  150   d  until sector switch  261  is re-engaged. This ensures that the gear train is always in the same spot after both cinching and power release when using actuator  150   d  for both functions, improving the quick release operation. 
     Latches may fail to open when an unusually heavy load is applied to the closure panel. Lift gates are particularly problematic, as they can easily be weighed down with snow or ice, and a greater force is required to lift them. If the striker does not immediately clear the fishmouth, the pawl might drop back into place. A snow load lever can help obviate the problem. Referring now to  FIGS. 21 a -21 d   , a snow load assembly is shown during a release cycle to help obviate the problem.  FIG. 21 a    shows compartment  86  on latch core  12 , when normally latched. A snow load lever  264  is pivotally mounted around a post  266  that extends from base plate  18  into compartment  86 . Snow load lever  264  includes a pawl arm  268 , ending in a hook  270 , and a release arm  272 . A spring  274  is coiled around snow load lever  264 , and biases it towards secondary pawl  60 . Snow load lever  264  is movable between a “resting position” (shown in  FIG. 21 a   ), and an ‘actuate position’ ( FIG. 21 b   ), where it pivots to lock secondary pawl  60 . 
       FIG. 21 b    shows compartment  86  on latch core  12 , when pawl  32  is released, but ratchet  30  does not move due to a snowload condition. When pawl  32  is released, secondary pawl  60  rotates in an opposite sense. As secondary pawl  60  rotates, a shoulder  276  on the secondary pawl  60  catches hook  270 . Secondary pawl is now prevented from rotating back to the resting position, leaving pawl  32  actuated. 
       FIG. 21 c    shows compartment  86  on latch core  12 , when the ratchet  30  moves to reset the snowload. This occurs when the decklid (or other closure panel) is manually opened. The manual door (not shown) opening pulls the striker out of the fish mouth  34 , which rotates ratchet  30  to the released position. The rotation of the ratchet moves the four-bar assembly. A cam arm  278  on cinch axle  216  engages release arm  272 , thereby pivoting snow load lever  264  in the direction of releasing hook  270  from shoulder  276 . 
       FIG. 21 d    shows compartment  86  on latch core  12 , pawl  32  returns to its normal resting position. With snow load lever  264  out of the way, secondary pawl  60  is free to return to its resting position, moving pawl  32  back to its resting position. 
       FIGS. 22 a -22 i    show an alternate embodiment of latch or latch assembly, indicated generally as  300 . Latch  300  may be an automobile latch suitable for use in cars and trucks, as may be. As with latch  10 , latch  300  in effect designates not merely a single latch, but rather a latch assembly system, in which a relatively small number of common major components can be assembled to yield a series of different products such as those of the matrix of  FIG. 2 . For example, in one embodiment, the latch may include only a manual operation feature. In another embodiment the latch may include both power and manual release. It may include power locking and unlocking. It may include power cinching. 
     In each instance there is a latch core,  320  sandwiched between a first external enclosure member, or casing, or shell, or cover, such as may be identified in the illustrations as housing  322 , and a second external enclosure member, which may have the form of an opposed backing wall, or plate, or cover, and is identified as wall member  324 . It may be that wall member  324  serves not only as an enclosure, but also as an adapter or base plate  326  having fittings, sockets, seats or accommodations to which other modules may mount according to the functional requirements of the overall latch assembly. While the various base plates may have portions having overlapping common functionality and morphology (i.e., layout), they may also differ according to the seats or accommodations required. 
     There is a latch core envelope  330  between the members that define the external enclosure of the latch, be it  10  or  300 . Envelope  330  exists whether the latch is to be used for a trunk, a gate, a lid, or a sliding door. Latch core  320  has a size and shape for containment within an envelope suitable for mounting (a) to a multiplicity of different brands of automobiles; and (b) to a multiplicity of configurations. That is to say, core  320  (and, for that matter, core  10 , may fit within the intersection set of latch core envelopes for gate, door, and sliding door applications for a multiplicity of brands of automobiles, such that the same latch core components may be supplied to different manufacturers and different models of cars and trucks, and different applications in those models. 
     In the examples of  FIGS. 22 a -22 i   , housing  322  may be termed a basket, and may have the form of a stamped or drawn metal cup  332 , with a attachment fittings, such as an array of fastening apertures  333 , formed in a seating array, or footing, which may have the form of an array of tabs or tangs, or may have the form of a peripherally extending flange  334 , which may be substantially planar or have substantially planar portions that present a flat surface, or surfaces, for mating engagement with the interior of an automobile door, lid or gate member, as may be. In the case of flange  334 , the under surface  335  may seat against the mounting surface in the vehicle. Housing  332  will in general have a depending peripheral or partially peripheral wall  336 , and a bottom, or base wall, or base wall portion  338 . Peripheral wall  336  may extend perpendicular to flange  334 , and, when mounted, protrude through the mounting surface of the vehicle. The projected footprint of depending cover peripheral wall  336  fits within a cover envelope, or outline, that is approximately 60 to 65 mm wide×60 to 65 mm long (with radiused corners) in the plane of flange  334 . One embodiment is about 62 mm×62 mm. It follows that latch core  320  fits within this footprint, less the thickness of wall  336 , leaving a projected latch core footprint of about, or slightly less than, 55 mm to 60 mm×55 mm to 60 mm (with radiused corners), and in one embodiment 57 to 58 mm×57 to 58 mm for all portions of latch core  320  that lie shy of the plane of the upper surface  337  of flange  334 . It may therefore be said that the projected footprint of the depending portion of the cover i.e., housing  332 , is less than 70 mm×70 mm, and the projected latch core footprint of those portions “submerged”, or shy, of the plane of surface  337  is less than 65 mm×65 mm, with appropriate allowance for corner radii as may be. Housing  332  will in general have a cut-out or accommodation or relief  340  formed in an endwall or sidewall portion of depending wall  336 . Relief  340  may extend some distance into base wall portion  338 , and may have the form of a blind-ended inwardly narrowing slot, generally having the shape of a fishmouth, relief being  340  of a size and shape suitable for admitting a door or gate striker, such as item  35  of  FIG. 9 , and such anti-noise or wear, or shock absorbing member or members as may be installed therein. 
     For the purpose of this discussion, the latch core envelope will be considered to be the volume that is (a) inside housing  332  as if relief  340  had not been made, but that peripheral wall  336  and base wall portion  338  were formed on continuous tangents or planes, or smooth curve conforming to their general shape; and (b) inside base plate  326 . Also for the purposes of this discussion, it may be noted that various shaft or rivet ends, fastening tangs or tabs or clips of latch core  320 , may extend outside this envelope, particularly to the extent that those features define attachment or location fittings by which latch core  320  is mounted to the cover, namely housing  332 . However, in addition to fitting through the projected footprint outline noted above, latch core  320  also fits within an envelope, or envelope criterion, as discussed below. 
     An envelope  330  may include a first portion  342  and a second portion  344 . First portion  342  may be termed the “bifurcated portion”, and is defined by a width W 342 , measured in the y-direction; a through-thickness H 342 , measured in the z-direction; and a length, L 342  measured in the x-direction. It may be noted that the x-y plane in this reference co-ordinate system is oblique relative to the plane of flange surface  337 . The angle of inclination may be in the range of 20 to 40 degrees, and, in one embodiment may be about 30 degrees. A closed position striker axis C 346  is defined as an axis running perpendicular to base wall portion  338  at the center of curvature of the major radiused portion of the cul-de-sac end  346  of relief  340 . This approximates the centerline of the striker when the latch is fully closed, and, if there is no end radius of curvature from which C 346  may be determined then C 346  should be taken as the design centerline of striker  35  in the closed position. L 342  is defined as the length between axis C 346  and the plane of the inside endwall portion of depending peripheral wall  336 . In one embodiment L 342  is less than 32 mm, and, in another embodiment is between 25 and 32 mm, and, in still another embodiment is between about 28 and 30 mm. Including the wall thickness of the endwall portion of depending wall  336 , the overall lengths may be less than 35 mm in the first instance, between 30 and 35 mm in the second instance, and between 30 and 32 mm in the third instance. L 342  may be termed the fishmouth travel length. W 342  may be taken as the inside width between the major or predominant substantially parallel and substantially planar portions of the sidewall portion  338 , and, if there is no such predominant portion, then the general wall width spacing taken in the plane normal to L 342  that intersect C 346 . This dimension may be less than 65 mm or 70 mm, and, in some embodiments may be about, or less than 60 mm. H 342  is the predominant through thickness clearance dimension between base wall portion  338  and wall member  324  in the region between C 346  and the open end of the fishmouth. This dimension does not include protruding asperities such as rivet heads, attachment tangs or tabs, or the ends of shaft or pivot members that seat in either member  322  or member  324 . Conceptually H 342  defines the through thickness of the zone in which moving internal parts in the lower two layers of latch core  320  may swing or rotate. As may be appreciated, the envelope could also be defined in terms of the outside dimensions of the cover  322 , and the position of its flange  334 . 
     As seen in  FIGS. 24 a  to 24 e   , one embodiment of latch core  320  may include a primary member, or base plate, or frame, or chassis, or carriage, or spider, or carrier, or platform, or substrate, or skeleton, or matrix member identified herein as a housing  350 . However it may be called, housing  350  provides a common dimensional datum member, or common frame of reference, for the location of the other members of latch core  320 . To that extent, housing  350  may be a monolithic casting, or molding, and may be made of a polymer, such as an high density plastic. The following latch core members of note are mounted to housing  320 : a ratchet,  352  and ratchet biasing member in the nature of a ratchet return spring  353  that biases ratchet  352  to the open or release condition, and a ratchet axle, identified as ratchet rivet  354  upon which ratchet  352  pivotally mounts; a pawl  356  and an axle identified as pawl rivet  355 ; a secondary pawl  358  and pawl biasing member in the nature of a pawl return spring  359 ; a position sensor switch identified as primary switch  360 ; a first status sensor member identified as striker primary switch lever  361 ; a second latch status sensor member identified as striker secondary switch lever  362  and a switch lever rivet  363 ; an overslam bumper  364 ; a switch lever biasing member in the nature of a spring  365  that biases both lever  361  and lever  362 ; and a snowload lever  366 , and its associated return spring  367 . As with latch core  10 , these various components may be designed to avoid unintended inertial moments about their fulcra and so may tend to avoid unintended release. 
     Housing  350  has a first face or side  370  and a second face or side  372 . First side  370  will arbitrarily be designated as the down side, and, as installed, faces toward base wall portion  338 . By contrast, second side  372  will be designated as the up side, and, as installed faces away from base wall portion  338 . Considering also the isometric views of  FIGS. 24 a  and 24 b   , ratchet  352  seats underneath first side  370 , i.e., between housing  350  and base wall portion  338 , with the ratchet pivot pin, rivet  354 , passing through the bored boss  375  of the accommodation identified as ratchet seat  374 . In this position ratchet  352  can pivot through the full range of motion between the positions identified in  FIGS. 25 a , 25 b , 25 c  and 25 d   . Similarly there is a pawl seat, or boss, or accommodation  376  with associated bore  377  for its pivot pin, namely rivet  357 . Pawl  356  is pivotally mounted on rivet  357  below housing  350 , and secondary pawl  358  is mounted on rivet  357  above housing  350 , with the depending lug, or force transfer arm  412  of secondary pawl  358  extending in the z-direction through the clearance allowance slot  378  such that secondary pawl  358  can bias pawl  356  in operation. The respective return spring biases pawl  356  to the engaged position for preventing release of ratchet  352 . As may be noted, pawl  356  has the form of a hook, with a tooth  380  that engages either the first stop or abutment  381  of first arm  382  of ratchet  352 , or the second stop or abutment  383  of second arm  384  of ratchet  352 , as may be. In this embodiment the cinch drive accommodation  386  is empty. Overslam bumper  364  is installed between the back coverplate  324  and abutment wall  388  at the inner end of the fishmouth. 
     The underside of housing  350  also has an array of fittings, or accommodations, or mountings that include primary (or pawl) and secondary (or striker) switch seats,  390 ,  392 , into which a primary (or pawl) switch  360  and secondary (or striker) switch  394 , respectively, may seat. A manually operated latch assembly, such as that version of latch core  320  shown in  FIG. 24 a    may have only a primary switch. The state of switches  360  and  394  (either ‘ON’ or ‘OFF’) is determined by the positions of the striker position sensor, namely striker primary switch lever  361  and striker secondary switch lever  362 , and of an arm of secondary pawl  358 . These switch levers are, in effect, signal transmitting members that transport a mechanical signal, in the form of a physical deflection of an input arm, from the location at which the signal is sensed, (i.e., the position of pawl  356 , or the position of a striker  35  in the fishmouth, as may be), to the input of the respective switch. 
     The main body of secondary pawl  358  occupies an accommodation  398  sunken into the top side of housing  350 . Secondary pawl  358  is mounted on a common axis in the primary pawl  356 , the two being located on either side of housing  350 . Depending foot  412  of secondary pawl  358  extends through motion clearance part  408  in housing  350  to seat within socket  378  of pawl  356 . Secondary pawl  358  also has an actuation input in the form of a lug  410  that protrudes upwardly from cover  324  for connection with such release input signal device or actuator as may be employed. Lug  410  may be located at the far end of secondary pawl  358  distant from foot  412 . Between lug  410  and its pivot shaft or pin (i.e., rivet  355 ) secondary pawl  358  may have a primary switch contact member in the nature of an extending wing, or cam, or arm, identified as a horn  409 . As installed in the illustrated embodiments, horn  409  extends, and travels, in a plane beneath the plane of snowload lever  366 . In this context, pawl  358  may itself have the function of a latch status sensor member since the position of secondary pawl  358  is a signal of the position of pawl  356 , and hence of one element of the status of the latch. 
     Housing  350  also has a fitting, seat, mounting or accommodation  418  for striker primary switch lever  361 , that accommodation including a boss  420  onto which a mating socket of striker primary switch lever  361  seats, thus defining a pivoting connection. Striker primary switch lever  361  has three arms extending away from the central socket. The first arm  414  of lever  361  may be considered the output arm, and is pivotally biased by spring  363  to bear away from primary switch  360 . The second arm,  416 , is similarly biased to protrude into the inner end of the fishmouth, and to be displaced therefrom when the striker occupies its fully cinched position. The third arm may be a counterweight arm. 
     Housing  350  includes an accommodation, or fitting, or mounting, or seat, for striker secondary switch lever  362 , in the form of a land  400  having a bore  401  into which a pivot axle or shaft in the form of a switch lever rivet  363  is mounted. There is an adjacent opening  405  that accommodates a motion transfer lug  404  of lever  362  that interacts with snowload lever  366 . Spring  363  biases major arm  422  to a default position in which it obstructs the fishmouth. I.e., introduction of a striker  35  into the fishmouth deflects arm  422  (the leading edge of arm  422  acting as a cam surface, in effect). This causes the second arm  430  of the lever to move, and, ultimately, to cause a change of state of second switch  394 . Thus lever  362 , functions as a status sensor member with respect to the position of the striker, and provides output to (a) the secondary switch  394 ; and (b) the snowload lever  366 , for which it acts as a reset arm. 
     Inasmuch as there may be a potential tolerance mis-match between arm  430  and the contact of switch  394 , housing  350  includes an integrally formed movable partition member  432 . Member  432  may have the form of a molded or living spring. The molded spring may have a relatively broad end, or paddle  434  located between switch  360  and horn  409  of secondary pawl  358 ; and also between switch  360  and arm  414  of striker primary switch lever  361 . The paddle provides a relatively large target front or first surface, or land, against which horn  409 , or arm  414 , or both, can act, and is sufficiently torsionally stiff that member  432  has effectively a single degree of freedom—namely deflection in the direction of action of switch  360 . The second, or back surface of paddle  434  acts against switch  360 . Partition member  432  may have an at rest position clear of switch  360 , and so is spring loaded when deflected, and therefore has a default bias away from switch  360 . 
     The logic of operation of switch  360  is thus that disengagement of pawl  356  in response to either (a) inward cinching motion of either of the ratchet toes against the cam surface defined by the back face of tooth  380 ; or (b) a release input deflection of lug  410  (such that hook  380  of pawl  356  is clear of the path of the stop, or finger, or abutment  381  of the first arm  382  of ratchet  352 , and clear of the path of abutment  383  of the second arm  384  of ratchet  352 , thereby permitting the ratchet to be driven to its open position, releasing the striker), will cause a mechanical input signal to be transmitted as horn  409  to pushes against member  432 , depressing the contact of switch  360 . Alternatively, the default bias of striker primary switch lever  361  will cause arm  414  to depress the contact of switch  360 . To obtain a change of state from this condition, namely to have arm  432  spring away from switch  360 , both contact inputs must be removed. That is, for switch  360  to change from the ‘On’ (a) lever arm  416  of a striker secondary switch lever  361  must be displaced by a striker, and pawl  356  must be in the engaged (i.e., passive or inactive default condition under its default biasing spring). The practical effect of this logic is that switch  360  will not have a temporary bump (such as might otherwise shut off a cinch drive motor) when the ratchet teeth bump past hook  380  during cinching to a closed position; and in the event that there is a tip-on-tip engagement of hook  380  with one or the one or the other of the ratchet teeth, the mechanism will tend not, erroneously, to infer that cinching is complete, but rather to continue driving until lever arm  416  is displaced. This is possible, in part, by having both the primary and secondary striker switches (a) have ranges of motion that overlap (and, in default obstruct) the fishmouth, whence they can be displaced on introduction of the striker; and (b) by making the levers thin and overlapping in the z direction to share a single accommodation layer by locally occupying only half of that layer. Member  432  thus becomes a summing bar, or a logical AND in the away direction, or a logical OR in the toward direction. In the release mode, an electrical controller may count the time interval following a release signal being given, and if it exceeds a threshold value without a change of state at switch  360 , such as half a second or a second, may infer that something is preventing the latch from opening, or that there is a fault. 
     Further, there are two striker status sensors. The primary sensor monitors whether the striker has reached the end of its range of travel and is seated in the fully cinched, or closed position at the inner end of the fishmouth. The other sensor changes state when the striker is near or at the beginning of its range of motion along the fishmouth moving inwardly (or at the end of its range of motion, moving outwardly). This may occur at the same time, or about the same time that ratchet  352  reaches the secondary position (i.e., toe  381  is rotationally inside the grasp of hook  380 ). Expressed differently, member  362  is used to sense the presence of the striker in the fishmouth slot along substantially its entire range of motion between the secondary position or condition, and the fully cinched or closed position or condition. Member  361  uses a different portion of the range of motion of the striker—namely the fully cinched, or closed, or primary, position only. Thus the change of state of switch  394  on release effectively signals that the striker has passed, or is passing, the secondary position on its way to the fully released position. 
       FIGS. 23 a -23 g    show a latching assembly  450  that includes a version of latch assembly  320  having a release input, as at  452 , and a power cinching input, as at  454 . This mechanism includes an externally accessible input interface, in the nature of a crank or crank assembly  456  that is accessible from inside the vehicle—i.e., from above the plane of flange  337 . Crank  456  may be driven by pulling on a cable  458 . Crank  456  includes a pivot member, or axle, or shaft  460  that extends into the latch body, and which may be termed a rivet, notwithstanding its function as a driven torsion rod or shaft. This shaft is perpendicular to the planes of swinging motion of the ratchet and pawl. A return spring  462  biases crank  456  to the inactive, or disengaged, state. The bottom, or inner end of crank  456  includes an output lug  464 . In contrast to the four bar linkage described above, the cinching mechanism includes a connecting link, in the form of a push rod is identified as finger  466 . While pinned at one end to lug  464 , the other, far or distal end  468  is not pinned to ratchet  352 . Ratchet  352  has a mating interface, or female socket, or accommodation identified as horn  470 , for receiving, and engaging, end  468 . This is a uni-directional force transfer interface: end  468  can exert a push across this interface, but cannot exert a pull. Thus there is a drive train, or force-transmission path, from the cinching input to ratchet  352 . The crank assembly passes in the z-direction clear through the accommodation or relief  386  formed in the carrier, housing  352 . The positions of the ends of crank assembly are fixed in the x and y directions by locating holes in the cover plate and in the backing plate, i.e., members  322  and  472 , and the position in the z-direction is established by the height at which lug  464  is fixed on shaft  460 . The cinching mechanism is activated when a striker is detected in the fishmouth (with the corresponding change in state of secondary switch  394 , and the logic of the position indicates that the latch is moving from an open to a closed condition. 
     Another feature of the core body is a pawl release signal sustainer, more commonly referred to as a snow load lever  366 . As before, housing  350  includes a snowload lever accommodation,  480 , in this case between housing  350  and the upper, or back plate member  324  or  472  (as may be) that includes a seat, or fitting or mount identified as boss  484 . Boss  484  mates with a corresponding bore of snow load lever  366 , so defining a pivoting connection. When the release mechanism is actuated, as, for example, by pulling lug  486  of secondary pawl  356 , the default spring bias of snow load lever  366  causes its first end  488  to rotate to block the return motion of the release actuator. When, however, the state of the striker switch lever pivots on release motion of the striker, its upstanding lug bears against the second end  490  of lever  366 , returning it to its normal, passive, disengaged position, and the release actuator returns to its home, or inactivated, position. This prevents reset of the secondary pawl unless the door (e.g., a trunk lid) has actually moved. The presence of the snowload lever, may be associated with the formation of an upward step in the top or back cover plate,  324 , as at  482 , immediately inboard of the overslam bumper. 
     The body of member  350  has a number of other features. First, it has downwardly protruding locating boss  494  by which the x and y location of member  350  is fixed relative to the cover, housing  322 . It also has indexing features, such as an upstanding tang or abutment wall  496  and keying rebates  498  by which the x and y location of backing plate member  324  is fixed relative to member  350 . Further, as may be noted member  350  has the bifurcation, generally indicated at  500  that defines the wide-mouthed, progressively tapering fishmouth accommodation for striker  35 . Member  350  includes a striker, or wear surface, or wear surface portion, or portions, in the thickened inlet wall portions  502 ,  504  that define the inlet guideway. Inasmuch as member  350  may be made of an high density plastic, wall portions  502 ,  504  may contribute to a lessening of latch noise. The inward end of the fishmouth is generally rounded, as at  506  in a manner generally corresponding to that of the cover, namely member  322 . By their nature, portions  502  and  504  are intended to stand proud of all other structure, so that they are encountered by the striker in preference to any other structure, and so protrude from, or be roughly flush with, the cover, i.e., member  322  in both the x-direction as at the open end of the fishmouth, and in the z-direction, where they overlap the cut edges of the cover plate. To that extent, these portions extend beyond the footprint, or envelope of the latch core proper. That envelope is defined by peripheral side wall portions  510 ,  512 , and by peripheral end wall portions  514 ,  516  as if a continuous tangent plane, P, extended between them. 
       FIGS. 25 a -25 d    show a progression of steps in closing.  FIG. 25 a    shows the position reached by latch core  320  when a striker has entered the claw, i.e., ratchet  352 , and the first toe has move within the hook tip of pawl  356 . The striker detection member, namely secondary switch lever  362 , has been deflected, and secondary switch  394  is in a state indicating the presence of the striker. Power clinching commences, causing push rod  466  to advance to reach the stage shown in  FIG. 25 b   , in which the push rod  466  is engaged in horn  470  at the rear end of ratchet  352 . Cinching continues, with push rod  466  driving the ratchet counterclockwise to the position in  FIG. 25 c   , in which second toe  384  of ratchet  352  rides up on the back of hook  380  of pawl  356 , tending to force pawl  356  to rotate counterclockwise outward. As second toe  384  of ratchet  352  clears hook of pawl  356 , pawl  356  springs back into its engaged (or default) position relative to abutment  383 , once again changing the state at primary switch  360 , such as may indicate that second toe  384  is entrapped, and striker  35  is in its fully cinched position. In this condition, the cinching motor is commanded to stop in the fully clinched condition of  FIG. 26 d   . The motor is then reversed and run to it “home” position. 
     This is seen in the logic of  FIGS. 26 a  and 26 b   . That is, the cinching cycle is assumed to start from a condition in which the latch core is in the open or release condition, with the ratchet turned fully clockwise to accept an incoming striker. The striker is pushed forward until the ratchet reaches the position indicated in  FIG. 25 a   . At this point the secondary switch opens, and a signal is sent to operate the clinching motion. The outward bump of the pawl in  FIG. 25 b    changes the state of the primary switch, i.e., to a closed condition. This does not affect operation of the cinch motor. The return change of state of the primary switch, from closed to open, however, provides the signal to the controller to stop the cinch motor, and then to drive it in the opposite direction to its “home” condition in which the lug and link of the cinch drive return to the position shown in  FIG. 25   a.    
     The release cycle is shown in  FIG. 26 b   . At some point an handle switch is triggered, be it manually, or electronically. Provided that the door is neither locked, nor subject to a child lock override, ultimately the release lever is tugged to move secondary pawl lever  358 , and hence to disengaged pawl  356 . For power release, the motor drives the cable pulling lever  358 . As soon as pawl switch  360  is released, the snow load lever engages under its default spring bias to prevent retraction of pawl lever  358 . Either (a) the operation of the motors and the default biasing of the ratchet spring causes rotation of ratchet  352  to release striker  35 , or, if there is snow or some other force holding the door or lid or gate closed, the operator manually opens the gate, then the state of the striker status monitoring sensor changes, as indicated by a change of state at switch  394 . For latch module  10 , the cinching motor runs to the open or released condition, for latch  320 , the motor may already be in its home position. If the controller times out before this signal occurs, then the cinch motor is powered to re-cinch the striker, and, in so doing, to reset snowload lever  366 . This may also tend to reset the pawl switch, and the cycle is ready to restart. 
     In this description, reference is made to a change of state of the switches. It is in large measure arbitrary whether a switch is nominally “ON” or nominally “OFF” for the logic of operation of the latches described above to apply. It is perhaps more to the point to indicate that operation of the various releases, locks, drives, and mechanisms depends on the switches having a first state and a second state, and that the system is responsive to changes of state of the switches, as described. The first switch state may be ‘ON’ and the second switch state may be ‘OFF’ in some embodiments, and the reverse in others, without changing the underlying logic. 
     The latch core, be it  12  or  320 , is thus mounted between an outside enclosure member e.g.,  322 , and an inside backing plate e.g., cover  324 , in a mechanical sandwich having a fishmouth for admitting a matably engageable striker  35 . The latch core has a substrate, namely housing  350 ; a ratchet  352  and ratchet biasing member; a pawl  356  and pawl biasing member; and a first status sensor member and an associated first status sensor switch, namely either the pawl sensor lever  361  or the striker status sensor lever  362 . The substrate has accommodations for the ratchet, the ratchet biasing member, the pawl and the pawl biasing member, and for the first status sensor member and the first status sensor switch. The core may include a second latch core status sensor member (i.e., it has both  361  and  362 ), and an associated second latch core status switch, for which the substrate has accommodations. The striker status sensor member,  362 , moves independently of both ratchet  352  and pawl  356 . The striker position or status sensor member,  362 , has a default bias toward obstructing said fishmouth. The ratchet and the pawl are pivotally movable in a shared layer. The sensor members are mounted in, and are movable in, a different layer. The ratchet and the striker status sensor have overlapping projected ranges of motion when seen normal to said layers. The substrate, namely housing  350 , has a first set of fittings constraining motion of said ratchet and said pawl to a first layer; and has a second set of fittings constraining motion of the status sensor members to an adjacent layer. The first set of fittings includes a first substantially planar wall. The second set of fittings include a second substantially planar wall parallel to and offset from said first substantially planar wall. The status sensor members and the switches are mounted in said second layer. The substrate may also define a third layer. The third layer has a release signal maintaining member mounted therein, namely the snowload lever. The substrate may also have mechanical signal transmission passages formed therethrough, such as items  386 ,  405  and  408 . The substrate is formed of a molded monolith, which may be plastic or metal. 
     The substrate may include and an integrally formed movable member interposed between the accommodation for the first status sensor switch and the first status sensor member. The movable member may be positioned to be acted upon by the first status sensor member. The movable member may be positioned to act upon the first status sensor switch when acted upon by the first status sensor member. The movable member may be wider than one or the other or both of the status sensor and the switch, and so may allow for any dimensional tolerance mismatch between them. The movable member may have the form of a living spring. It may be resiliently biased to a default position clear of said first switch. The substrate has a switch accommodation depth, and the movable member is constrained to deflect in a first degree of freedom in a direction cross-wise to that depth. The width corresponds substantially to the accommodation depth. 
     Further the substrate is formed of a molded monolith having a striker motion accommodating slot defined therein, namely the fishmouth. The first status sensor member, lever  362 , is operable to sweep through a range of motion. The range of motion overlaps at least part of the striker motion accommodating slot. The ratchet and the first status sensor member are each mounted to pivot in a respective plane. The ratchet and the first status sensor member are not co-planar. The ratchet and the first status sensor member sweep out respective ranges of motion that are overlapping, and can sweep past each other. The substrate also includes fittings defining accommodations for a second status sensing member, namely lever  361 , and a cooperable second status sensing member switch, namely switch  360 , those accommodations being in a layer other than the first layer. 
     In summary, the latch core, be it item  320  or item  12 , includes a matrix member that provides a locational datum, or frame of reference for the various moving members of the latch core (e.g., the ratchet, the primary and secondary pawl, the switch lever, or levers, and the switch, or switches. It may also provides a frame of reference for the snowload lever, if there is one, assembly, and either directly or indirectly provides a datum for the cinch mechanism, if there is one. The latch core is divided into layers, or levels. The matrix member may also define a geometric relationship of the parts such that the resulting assembly falls within a particular space envelope, such as a common denominator envelope between a range of latch types and uses. 
     In one layer, which may be the first or bottom layer, are the ratchet and pawl. In another layer, which may be a second layer, is the secondary switch lever, which detects the presence of a striker in the fishmouth. The primary switch lever may also be mounted to operate in the second layer, although it could, alternatively be mounted to operate in the first layer. The striker switch detection lever operates in a different layer, or plane from the ratchet. It pivots independently of the ratchet, and swings through a motion envelope that overlaps the motion envelope swept by the ratchet. To the extent that separate plane are defined for each layer, they may be defined as the planes of the center of these elements. The switches are in the planes, or layers of the respective switch levers. The snowload lever is in yet a third plane, or layer. To achieve this, member  350  has, in effect, a first level, or plateau or shelf, or array of surfaces that is parallel to the plane of motion of the ratchet and pawl. 
     This array of surfaces may include co-planar surfaces, and may include the ratchet boss and neighbouring land of one side or leg of the bifurcation; and pawl shelf of the other side or leg of the bifurcation. Member  350  also has a second shelf, or layer or array of surfaces, which may be recessed (or shy of) the surfaces of the first shelf or layer, and may include a recess and surface for the primary switch lever, and a recess or region and surface for the secondary switch lever, and surfaces, or regions on substantially the same plane on which the primary and secondary switches may mount. The switch levers and switches do not need to be mounted in the same plane as each other, and, the switch levers, or portions of them, may overlap and undergo movement with respect to each other about their respective pivots. Member  350  may also have a third shelf, or surface or array of surfaces such as may accommodate the parallel planar pivoting motion of secondary pawl  358 , and a fourth surface, or array of surfaces such as may defined the location of the snow load lever. The matrix member may include appropriate pivot or fulcrum fittings, whether bores for shafts or bosses for sockets, for these various moving members, and may include motion or signal (or both) transmission passages between the various layers, whether those passages or openings allow for lost motion or not. 
     An latch function adapter plate, such as may be termed a brain plate, may be mounted to latch  300  in much the same manner as to latch  10 . The choice of adapter plate will be determined by the desired function or functions and the cinching, locking, or other modules to be combined with it for a particular application as described above. In that context, the latch may be seen as a device having two input ports or signal receiving devices, those being the release and the cinch drive input; and two output or monitoring signals, those being the two switch states. In this circumstance, there may be more than two switch input sensor members, and it may be that none of the input sensor members is directly connected to, or directly monitors, ratchet position or operation. 
     The principles of the present invention are not limited to these specific examples which are given by way of illustration. It is possible to make other embodiments that employ the principles of the invention and that fall within its spirit and scope of the invention. Since changes in and or additions to the above-described embodiments may be made without departing from the nature, spirit or scope of the invention, the invention is not to be limited to those details.