Patent Abstract:
A slam-capable, T-handle operated rotary latch has a pan-shaped housing for nesting the T-handle and employs a single rotary jaw that is releasably retained in its latched. position by a rotary pawl. The latch has spaced first and second side plates that sandwich the rotary jaw, the rotary pawl and a torsion spring that biases the jaw toward an open position. The pawl defines a release trigger which, when tripped, permits the jaw to be pivoted by the torsion spring to an open position. A compact arrangement of stop formations and independently pivotal operating arms is provided adjacent a backwall of the housing to enable the T-handle to trip the release trigger during forward pivoting of the T-handle and the operating arms in opposition to the action of a return spring, and to limit reverse pivotal movement of the operating arms and the T-handle under the influence of the return spring.

Full Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a novel and improved slam-capable, flush-mountable, T-handle operated rotary latch assembly connected to rear portions of a pan-shaped housing, with a pair of pivotal operating arms that rotate together with the T-handle in a forward direction of rotation to operate or “unlatch” the latch, wherein the operating arms engage stops defined adjacent a backwall of the housing to limit reverse direction rotation of the operating arms and the T-handle, and wherein a key operated lock may be provided to retain the operating arms in their non-operated positions. More particularly, the present invention relates to a T-handle operated rotary latch unit of the type described that preferably employs a rotary latch assembly of the type having a single rotary jaw that is releasably retained in its latched position by a rotary pawl, with the latch having spaced first and second housing side plates that sandwich the rotary jaw, the rotary pawl and a torsion spring that biases the jaw toward an open position, with the side plates defining aligned first and second U-shaped notches that cooperate with a third U-shaped notch formed in the rotary jaw to concurrently receive and to latchingly retain a suitably configured strike formation, and with one of the housing side plates being rigidly connected to the pan-shaped housing by at least a tab-like formation that overlies the backwall and defines one of the stops, wherein pivotal movement of the operating arms trips a release trigger of the pawl in response to operation of the T-handle to permit the rotary jaw to be pivoted by the torsion spring to an open position. 
     2. Prior Art 
     Flush mountable, paddle handle operated latches and locks are known that employ rotary latch bolts, also referred to as “rotary jaws,” wherein the jaws are provided with U-shaped strike-receiving notches for latchingly receiving and releasably retaining suitably configured strike formations. It also is known to utilize a spring-biased operating arm that is pivotally connected to a back wall of a pan-shaped housing to transfer unlatching movement from a rearwardly extending projection of a housing-pivoted paddle handle to a rotary latch assembly that is connected to the pan-shaped housing, as is exemplified by U.S. Pat. No. 5,586,458 issued Dec. 24, 1996 to Lee S. Weinerman et al, entitled HANDLE OPERABLE ROTARY LATCH AND LOCK, and U.S. Pat. No. 4,320,642 issued Mar. 23, 1982 to John V. Pastva, Jr., entitled PADDLE LOCKS WITH HANDLE DISCONNECT FEATURES, the disclosures of which are incorporated herein by reference. 
     Other disclosures of latch and/or lock units that employ rotary jaws are found in U.S. Pat. No. 4,320,642 issued Mar. 23, 1982 to. John V. Pastva, Jr., entitled PADDLE LOCKS WITH HANDLE DISCONNECT FEATURES; U.S. Pat. No. 4,917,412 issued Apr. 17, 1990 to Jye P. Swan et al, entitled VEHICLE DOOR LOCK SYSTEM PROVIDING A PLURALITY OF SPACED ROTARY LATCHES; U.S. Pat. No. 4,896,906 issued Jan. 30, 1990 to Lee S. Weinerman et al entitled VEHICLE DOOR LOCK; and, U.S. Pat. No. 5,069,491 issued Dec. 3, 1991 to Lee S. Weinerman et al entitled VEHICLE DOOR LOCK SYSTEM. The disclosures of these patents also are incorporated herein by reference. 
     The rotary latch and/or lock units that are disclosed in the four patents identified just above are of a relatively heavy duty type that often are employed in “personnel restraint applications,” typically on doors of passenger compartments of vehicles. These heavy duty units employ pairs of lousing-mounted rotary jaws, with the jaws being sandwiched between pairs of housing side plates, and with notches that are formed in each pair of rotary jaws being configured to receive and engage opposite sides of a suitably configured strike formation, typically a cylindrical stem of a striker pin. While both of the housing side plates are provided with U-shaped notches, neither of these notches defines a strike engagement surface that cooperates with a notched rotary jaw to latchingly receive and releasably. retain a strike formation. The notches that are formed in the jaws, not the notches that are formed in the housing side plates, receive, engage and latchingly retain suitably configured strike formations. 
     Lighter duty rotary latch and lock units that employ single rotary jaws also are known, as exemplified by the following: U.S. Pat. No. 5,884,948 issued Mar. 23, 1999 to Lee S. Weinerman et al, entitled ROTARY LATCH AND LOCK; U.S. Pat. No. 5,611,224 issued Mar. 18, 1997 to Lee S. Weinerman et al, entitled HANDLE OPERABLE ROTARY LATCH AND LOCK; U.S. Pat. No. 5,586,458 issued Dec. 24, 1996 to Lee S. Weinerman et al, entitled HANDLE OPERABLE ROTARY LATCH AND LOCK; U.S. Pat. No. 5,564,295 issued Oct. 15, 1996 to Lee S. Weinerman et al, entitled HANDLE OPERABLE ROTARY LATCH AND LOCK; U.S. Pat. No. 5,439,260 issued Aug. 8, 1995 to Lee S. Weinerman et al, entitled HANDLE OPERABLE ROTARY LATCH AND LOCK; and, U.S. Pat. No. 4,312,203 issued Jan. 26, 1982 to Edwin W. Davis entitled FLUSH-MOUNTABLE LOCK WITH ACTUATOR DISCONNECT FEATURE. 
     While flush-mountable T-handle operated latch and lock mechanisms of various types are known, as is shown by U.S. Pat. No. 4,706,478 issued Nov. 17, 1987 to Jye P. Swan et al, entitled ROTARY HANDLE OPERATED DOOR LOCK, and while T-type operating handles are sometimes preferred over paddle-type operating handles in some applications, relatively little has been done until now to provide flush mountable, T-handle operated rotary latch assemblies that can be substituted for paddle handle operated rotary latch assemblies. 
     Although considerable thought has been devoted during recent years to providing improved, more compact and highly reliable handle-to-latch interconnection mechanisms in paddle handle operated rotary latches, it has seldom been possible to make much use of the resulting improvements in T-handle operated rotary latches. One of the reasons why improvements made in the handle-to-latch interconnection mechanisms of paddle handle operated rotary latches tend to be unsuitable for use in the handle-to-latch interconnection mechanisms of T-handle operated rotary latches has to do with the very different way in which paddle handles and T-handles connect to and pivot with respect to their associated pan-shaped flush mountable housings. 
     Whereas paddle handles execute a simple pivoting action about axes that parallel the back walls of their associated housings when moving between their non-operated and operated positions, T-handles ordinarily accomplish no unlatching movement at all when they pivot between their nested and extended positions about axes that substantially parallel the back walls of their associated housings; rather, they accomplish unlatching only when pivoted about axes that extend substantially perpendicular to the back walls of their associated housings. This very basic difference in the character and operation of the two types of handles has necessitated the use of very different handle-to-latch interconnection mechanisms on paddle-handle operated and T-handle operated rotary latch and lock units. 
     SUMMARY OF THE INVENTION 
     The present invention provides a slam-capable, flush-mountable, T-handle-operated, single-jaw rotary latch assembly having a jaw-retaining rotary pawl with an associated “trigger” that can be tripped to “unlatch” the rotary latch by a compact arrangement of two independently movable operating arms that pivot in a forward direction alongside a back wall of the housing for executing an “unlatching” movement in response to movement of the T-handle from its non-operated position to its operated position, with a compact arrangement of stops being provided adjacent the back wall for limiting the pivotal return movement of the operating arms and the T-handle as these three components return to their non-operated positions. 
     One feature of the invention resides in the provision of first and second independently movable operating arms that pivot alongside the back wall of a pan-shaped housing to drivingly connect a T-handle to a rotary latch assembly to operate, trip or unlatch the rotary latch assembly in response to pivotal movement of the T-handle from a non-operated position to an operated position. The first operating arm is relatively short and is rigidly connected to a stub shaft that is pivotally connected to the housing and carries the T-shaped grip of the operating handle. This first arm typically pivots through about a quarter-turn of movement—a range of usually about thirty degrees—when the T-handle is pivoted between the non-operated and operated positions. The second operating arm is relatively long, is pivotally connected to the back wall of the housing, and typically pivots through a much smaller range of movement—usually about fifteen degrees—to trip, operate or unlatch the rotary latch assembly by moving a trigger formation of the rotary latch assembly. The use of a pair of operating arms that cooperate in this manner, are of significantly different lengths and pivot through significantly different ranges of movement to provide the heart of a very compact and reliable handle-to-latch interconnection mechanism provides one feature of note. 
     Another feature resides in the manner in which stops are provided in a compact and reliable way to limit the return pivotal movement of not only the two operating arms but also the T-handle—movement that takes place as the result of the biasing action of a spring that is interposed between the housing and the second, relatively long operating arm. A return movement stop for the first, relatively short operating arm is provided by a formation of the first operating arm that is configured to engage a tab-like extension of one of the side plates of the rotary latch assembly—an extension that overlies the back wall of the housing and is rigidly connected thereto to at least assist in mounting the rotary latch assembly on the pan-shaped housing. The use of a tab-like mounting formation of a rotary latch assembly to perform a second duty of providing a return movement stop for an operating arm that is connected to a T-handle (and therefore also serves to stop return pivotal movement of the T-handle) provides another feature of note. 
     Still another feature resides in the use of a formation of the first operating arm to stop the return pivotal movement of the second operating arm. Contemplated within the possibilities provided by this option are: 1) the use of engaged driving formations provided at distal ends of both of the operating arms to stop the return pivotal movement of the second operating arm; or 2) the provision of a stop surface at a “hub” end of the first operating arm (adjacent the pivot axis of the first operating arm and adjacent a location of connection between the first operating arm and a stub shaft that carries the graspable T-shaped component of the T-handle) that is engaged by the second operating arm to stop the return pivotal movement of the second operating arm (an arrangement that can be utilized, if desired, to halt the return movement of the second operating arm before halting the return movement of the first operating arm); or, 3) the concurrent use of both of these types of stops (whereby spaced portions of the second operating arm engage spaced portions of the first operating arm to stop the return pivotal movement of the second operating arm at the same time that return pivotal movement of the first operating arm is stopped), in applications where dual-stop contact between the operating arms and concurrent stoppage of the movement of both operating arms may be desired. 
     Stating one feature of the invention in another way, while the stop that is defined by the tab-like extension of one of the side plates of the rotary latch assembly may effectively serve to limit the pivotal movement of both of the operating arms and the T-handle as these members pivot to their non-operated positions, a second stop defined by the first operating arm may be engaged by the second operating arm to independently halt the return pivotal movement of the second operating arm. 
     In preferred practice, the stop that is defined by the tab-like extension of one side plate of the rotary latch assembly serves to stop the return rotation of both of the operating arms. Where this preferred arrangement is employed, a single spring interposed between the housing and the second operating arm can be used to bias both of the operating arms into engagement with their respective stops to limit the return pivotal movement of the first and second operating arms and the T-handle when these three pivotal elements reach their non-operated positions. 
     While the preferred practice of the present invention calls for the use of rotary latch assemblies of the type disclosed in U.S. Pat. No. 5,586,458, it is contemplated that features of the invention including its advantageous arrangement of dual operating arms and their associated return-movement stops can be utilized with other types of rotary latch assemblies that are adapted by providing one of their housing side plates with a tab-like extension that overlies and is connected to a housing back wall at a location wherein the tab-like extension can serve dual duty as a mount for connecting the latch assembly to the back wall, and as a stop for limiting return pivotal movement of one of the operating arms that is connected to a T-handle, and therefore also serves to limit return pivotal movement of the T-handle. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features, and a fuller understanding of the invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings, wherein: 
     FIG. 1 is an exploded front perspective view of components of one embodiment of a T-handle operable rotary latch and lock unit that incorporates features of the present invention; 
     FIG. 2 is a rear perspective view thereof, on an enlarged scale, showing the unit with its components assembled, with its rotary jaw in a latched position, with its first and second operating arms in their non-operated positions, and with its locking cam in a locked position—which necessitates that the T-shaped operating handle of the unit be in its non-operated position; 
     FIG. 3 is a rear elevational view thereof; 
     FIG. 4 is a rear elevational view similar to FIG. 3 but with the locking cam in an unlocked position, and with other components moved in response to movement of the T-shaped operating handle to its operated position, namely with the first and second operating arms shown in their operated positions causing the the rotary pawl to move to “unlatch” the rotary jaw, and with the rotary jaw in an unlatched position; 
     FIG. 5 is a sectional view as seen from a plane indicated by a line  5 — 5  in FIG. 3; 
     FIG. 6 is a sectional view as seen from a plane indicated by a line  6 — 6  in FIG. 4; 
     FIG. 7 is a sectional view as seen from a plane indicated by a line  7 — 7  in FIG. 3; 
     FIG. 8 is a sectional view as seen from a plane indicated by a line  8 — 8  in FIG. 4; 
     FIGS. 9,  10  and  11  are sectional views as seen generally from a plane indicated by a line A—A in FIG. 5, and are provided to schematically depict a sequence of three steps by which a suitably configured strike comes to be received in and latchingly retained by rotary latch components of the first embodiment, with FIG. 9 showing the latch “unlatched” and the strike not yet engaging the latch, with FIG. 10 showing the strike being received by the latch and showing a preliminary latching orientation of latch components, and with FIG. 11 showing a fully latched configuration of the strike and latch components; 
     FIG. 12 is a rear perspective view of a second embodiment of a latch and lock unit that incorporates features of the invention, with its rotary jaw in a latched position, with its first and second operating arms in their non-operated positions, and with its locking cam in a locked position—which necessitates that the T-shaped operating handle of the unit be in its, non-operated position; 
     FIG. 13 is a rear elevational view thereof; 
     FIG. 14 is a rear elevational view similar to FIG. 13 but with the locking cam in an unlocked position, and with other components moved in response to movement of the T-shaped operating handle to its operated position, namely with the first and second operating arms shown in their operated positions causing the the rotary pawl to move to “unlatch” the rotary jaw, and with the rotary jaw in an unlatched position; 
     FIG. 15 is a rear perspective view of a third embodiment of a latch and lock unit that incorporates features of the invention, with its rotary jaw in a latched position, with its first and second operating arms in their non-operated positions, and with its locking cam in a locked position—which necessitates that the T-shaped operating handle of the unit be in its non-operated position; 
     FIG. 16 is a rear elevational view thereof; 
     FIG. 17 is a rear elevational view similar to FIG. 16 but with the locking cam in an unlocked position, and with other components moved in response to movement of the T-shaped operating handle to its operated position, namely with the first and second operating arms shown in their operated positions causing the the rotary pawl to move to “unlatch” the rotary jaw, and with the rotary jaw in an unlatched position; 
     FIG. 18 is a rear perspective view of a fourth embodiment of a latch and lock unit that incorporates features of the invention, with its rotary jaw in a latched position, with its first and second operating arms in their non-operated positions, and with its locking cam in a locked position—which necessitates that the T-shaped operating handle of the unit be in its non-operated position; 
     FIG. 19 is a rear elevational view thereof; and, 
     FIG. 20 is a rear elevational view similar to FIG. 19 but with the locking cam in an unlocked position, and with other components moved in response to movement of the T-shaped operating handle to its operated position, namely with the first and second operating arms shown in their operated positions causing the the rotary pawl to move to “unlatch” the rotary jaw, and with the rotary jaw in an unlatched position. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. 1-11, one embodiment of a T-handle operable rotary latch and lock unit embodying features of the present invention is indicated generally by the numeral  100 . The unit  100  has a pan-shaped housing  110  onto which are mounted a T-handle type of operating handle  150 , a key-operated cam lock assembly  200 , first and second operating arms  250 ,  300 , and a rotary latch assembly  400 . 
     Referring to FIGS. 9-11, a typical strike that may be engaged by the latch and lock unit  100  is indicated generally by the numeral  50 . As depicted, the strike  50  has an enlarged head  52  and a generally cylindrical formation of smaller diameter  54 —which is what is engaged by the rotary latch assembly  400 . The strike  50  is usually mounted on a door frame or other structure (not shown) that will be positioned adjacent the unit  100  when a closure (not shown) on which the unit  100  is mounted is in its closed position. 
     Referring to FIG. 1, the pan-shaped housing  110  is a generally rectangular metal stamping having a perimetrically extending, substantially flat mounting flange  120  which surrounds a forwardly facing recess  130 . Opposed, parallel extending side walls  123 ,  125 , and opposed, parallel extending end walls  127 ,  129  are joined by smooth bends to extend perimetrically around the recess  130 , and are joined by smooth bends to the mounting flange  120 . 
     A majority of the recess  130  is relatively deep, and is closed by a main back wall portion  132  that is substantially flat. One end region of the recess  130  is more shallow, and is closed by a minor back wall portion  134  that also is substantially flat. A portion  136  of the end wall  129  forms a transition between the back wall portions  132 ,  134 . Smooth bends join the back wall portions  132 ,  134  to adjacent portions of the side and end walls  123 ,  125 ,  127 ,  129 . 
     A main back wall opening  142  is formed through the main back wall portion  132 . A lock mount opening  144  is formed through the minor back wall portion  134 . The lock mount opening  144  is generally circular except for two flats  146  formed along opposite sides thereof. The main back wall opening  140  is circular and is located midway between the end walls  127 ,  129  while being spaced more closely to one of the side walls  123 ,  125  than to the other of the side walls,  123 ,  125 . If the opening  140  is closer to the side wall  123  than to the side wall  125 , the T-handle  150  folds toward the side wall  125  when being nested within the recess  130 ; and, if the opening  140  is closer to the side wall  125  than to the side wall  123 , the T-handle folds toward the side wall  123  when being nested within the recess  130 —by which arrangement so-called “left” and “right” versions of the unit  100  are defined. 
     The T-handle type of operating handle  150  includes a stub shaft  152  that extends along a pivot axis  155  through the main back wall opening  142 . A T-shaped handgrip member  170  is situated on the front side of the back wall portion  132 , and is pivotally connected to a front end region  154  of the stub shaft  152  by a pivot pin  156 . The first operating arm  250  is rigidly connected to a rear end region  158  of the stub shaft  152  by a threaded fastener  159 . The threaded fastener  159  extends through a hole  252  defined by a hub  254  located at one end region of the first operating arm  250 , and is threaded into a hole (not shown) formed in the rear end region  158  of the stub shaft  152 . 
     The stub shaft  152  has a central region  160  of cylindrical cross-section located between the front and rear end regions  154 ,  158 . Flat surfaces  164  are formed on opposites of the front end region  154 . A hole  163  is formed through the front end region  154  and opens at opposite ends through the flat surfaces  164 . The axis of the hole  163  extends perpendicular to the planes of the parallel-extending flat surfaces  164 . 
     Flat surfaces  168  (one of which is shown in FIG. 1) are formed on opposite sides of the rear end region  158  of the stub shaft  152 . The hub  254  of the first operating arm  250  has an opening  256  configured to receive the rear end region  158  of the stub shaft  152 . The opening  256  is defined, in part, by opposed flat surfaces  258  (one of which is shown in FIG. 1) that are configured to mate with the flat surfaces  168  on the rear end region  158  of the stub shaft  152 , to establish a driving connection between the stub shaft  152  and the first operating arm  250  to ensure that the first operating arm  250  will pivot with the stub shaft  152  when the stub shaft is rotated about the pivot axis  155 . 
     The T-shaped handgrip member  170  has an elongate centrally located stem  172  that connects at one end with a yoke  176 , and at the other end with a crossbar  178 . The yoke  176  has a pair of spaced, parallel extending legs  174 , with aligned holes  173  extending therethrough. The pivot pin  156  extends through the yoke leg holes  173  and through the stub shaft hole  153  to pivotally connect the T-shaped handgrip member  170  to the stub shaft  152  for movement between a nested position (see FIGS. 5 and 7) and an extended position (see FIGS.  6  and  8 ). When the T-shaped handgrip member  170  is in its nested position, it is received within the recess  130  of the pan-shaped housing  110 . 
     A driving connection is defined between the T-shaped handgrip member  170  and the stub shaft  152 ,by virtue of the yoke legs  174  extending closely alongside the flat surfaces  164  of the stub shaft  152 , and by virtue of the pivot pin  156  extending through the holes  153 ,  173  of the yoke  176  and the front end region  154  of the stub shaft  152 . This driving connection ensures that, when the T-shaped handgrip member  170  is in its extended position (see FIGS. 6 and 8) and is rotated about the pivot axis  155 , the stub shaft  152  will rotate with the handgrip member  170 . Because the T-shaped handgrip member  170  is closely received within the recess  130  of the pan-shaped housing  110  when nested, the T-shaped handgrip member  170  must be pivoted to its extended position in order for tile T-handle operating handle  150  to rotate about the axis  155  to pivot the first operating arm  250  between its non-operated position (best seen in FIG. 3) and its operated position (best seen in FIG.  4 ). 
     Referring to FIGS. 1,  5  and  6 , flat surfaces  180  are defined at the base of the yoke legs  174 . Flat surfaces  182  also are defined along one side of the yoke legs  174 . When the T-shaped handgrip member  170  is nested (as shown in FIG.  5 ), an escutcheon washer  190  carried on the front end region  154  of the stub shaft  152  is biased into engagement with the flat surfaces  180  by a spring washer  192  that is interposed between the escutcheon washer  190  and the back wall portion  132  of the housing  110 . When the T-shaped handgrip member  170  is extended (as shown in FIG.  6 ), the escutcheon washer  190  is biased by the spring washer  192  into engagement with the flat surfaces  182 . When the T-shaped handgrip member  170  is pivoted between its nested and extended positions, rounded surfaces  184  that connect the flat surfaces  180  with the flat surfaces  182  compress the escutcheon washer  190  toward the back wall  132  of the housing  110  in opposition to the action of the spring washer  192 . This interaction between the flat surfaces  180 ,  182 , the rounded surfaces  184 , the escutcheon washer  190  and the spring washer  192  serve to detent the T-shaped handgrip member  170  toward its nested and extended positions, as is well understood by those who are skilled in the art inasmuch as this manner of detenting is commonly used with foldable T-handles that are nestable within pan-shaped housings. 
     When the operating handle  150  is pivoted about the axis  155  of the shaft  152  away from its normal non-operated position, shown in FIGS. 5 and 7 to its operated position, shown in FIGS. 6 and 8, the first operating arm  250  is caused to move from its non-operated position, shown in FIG. 3, to its operated position, shown in FIG.  4 . When the first operating arm  250  moves from its non-operated to its operated position, it engages and pivots the second operating arm  300  from its non-operated position, shown in FIG. 3, to its operated position, shown in FIG. 4, to “unlatch” the rotary latch sub-assembly  400  from latchingly engaging a suitably configured strike formation  50  (see FIGS.  7 - 9 ). 
     Referring to FIGS. 1-6, the key-operated lock mechanism  200  is a commercially purchased item that has a generally tubular body  202  that carries threads  204 , with opposite side portions defining flat surfaces  206  (one of which is shown in FIG.  1 ). The housing  202  is received in the lock mounting opening  144 , with the flat surfaces  206  engaging the flats  146  to prevent the body  202  from rotating relative to the housing  110 . A nut  208  is tightened on the threads  204  to mount the body  202  on the housing  110 . Carried within the tubular body  202  is a key-operated rotatable plug  212  that carries a cam  210  at a location spaced rearwardly from the tubular housing  202 . The cam  210  is held in place by a threaded fastener  209 . The cam  210  is movable between a “locked” position, as depicted in FIGS. 2,  3  and  5 , and an “unlocked” position, as depicted in FIGS. 4 and 6. Movement of the cam  210  between its locked and unlocked positions is effected by inserting a key  207  into the plug  212 , and by turning the key between the unlocked position, as depicted in FIGS. 3 and 5, and the locked position, as depicted in FIGS. 6 and 8. 
     Referring to FIGS. 1-4, the first operating arm  250  has a relatively flat, generally triangular shape except for the hub  252  which is located at one of the corner regions of the triangle, except for a rearwardly extending driving formation  234  which is located at another of the corner regions of the triangle, and except for a rounded stop surface  236  which is defined at the third corner of the triangle. The hub  252  has a rounded outer surface  242  that is interrupted by the provision of flat surfaces  244  on opposite sides thereof. The driving formation  234  has something of a round-cornered trapezoidal cross-section that engages a rearwardly turned driving formation  272  of the second operating arm  300 . The rounded stop surface  238  is configured to engage a tab-like extension  390  of a side plate  402  of the rotary latch  400  when the first operating arm  250  (and hence the operating handle  150 ) is in its non-operated position, as depicted in FIGS. 2 and 3. 
     Referring to FIGS. 1-4, the second operating arm  300  has a more complex configuration than the first operating arm  250 . The second operating arm  300  is formed as a one-piece stamping that has a generally flat main portion  252  which defines a mounting hole  260  (see FIG.  1 ), and “regions”  262 ,  266 ,  268  that are provided to connect the operating arm  300  with other components. 
     The connection region  262  includes the rearwardly turned driving formation or flange  272  which is engaged by the rearwardly extending driving formation  234  of the first operating arm  250 . The connection region  262  also includes a small rearwardly turned formation  274 . A tension coil spring  282  connects with the formation  274  and with a hole  399  formed through the side plate  402  of the latch assembly  400  to bias the second operating arm  300  away from its operated position (see FIG. 4) toward its non-operated position (see FIGS.  2  and  3 ). 
     The connection region  266  includes a surface  276  that is engaged by the cam  210  when the key-operated lock  200  positions the cam  210  in its locked position (shown in FIGS. 2,  3  and  5 ), but that is disengaged by the cam  210  when the key-operated lock  200  positions the cam  210  in its unlocked position (shown in FIGS.  4  and  6 ). 
     Tile connection region  268  also includes a pawl-engaging formation  278  for transferring “unlatching” movement to a rotary pawl  420  of the rotary latch assembly  400 , as will be explained shortly. The pawl-engaging formation  278  extends through a slot  350  formed in a housing side plate  402  of the rotary latch assembly  400 . By this arrangement, and by sizing the slot  350  so that it relatively closely receives the pawl-engaging formation  278 —to aid in guiding movements of the second operating arm  300 , and in supporting the second operating arm  300  to resist deformation of the second operating arm  300  during applications of undue force to the latch and lock unit  100 . 
     A shoulder rivet  290  (or other suitable fastener) is rigidly connected to the main back wall portion  132  of the pan-shaped housing  110 , and provides a central diameter  295  (see FIG. 1) that is received in a slip fit within the mounting hole  260  of the mounting arm  250 —to mount the second operating arm  300  on the housing  110  for pivotal movement relative thereto about the axis of the rivet  290 . 
     Referring to FIG. 1, the latch assembly  400  has what will be referred to as a “housing” that consists of first and second “housing side plates”  402 ,  404  that are held together by two identical spacers or bushings  406 ,  408  that extend along transverse axes  456 ,  458 . 
     The housing side plate  402  is substantially flat except for a centrally located tab-like extension that defines the mounting tab  390 . The tab-like extension or tab  390  extends substantially perpendicular to the plane of other portions of the housing side plate  402  at a location spaced between two other mounting tabs  392 ,  394 . The tab  390  overlies and is welded to a portion of the back wall  132  of the housing  110 . The tabs  392 ,  394  overlie and are welded to portions of the side wall  125  of the housing  110 . 
     The housing side plate  404  is substantially flat except 1) for an elongate recess  396  stamped therein,  2 ) for a pair of transversely extending flanges  471  (see FIG. 2) and  472  (see FIG. 1) are joined by small radius bends to the main flat portion  403  of the side plate  404 . 
     Referring to FIG. 1, the bushings or spacers  406 ,  408  are tubular (i.e., they have hollow interiors), and have reduced diameter end regions  416 ,  418  that are sized to be received in a slip fit within hex-shaped holes  426 ,  428  that are formed in the flat central portions  401 ,  403  of the side plates  402 ,  404 , respectively. To securely retain the hollow, reduced diameter end regions  416 ,  418  in place within the hex-shaped holes  426 ,  428  (to thereby rigidly interconnect the housing side plates  402 ,  404 ), the end regions  416 ,  418  are expanded within the hex-shaped holes  426 ,  428  (see FIG. 2) to fully engage the sides of the hex-shaped holes  426 ,  428 . Because the holes  426 ,  428  are hex-shaped, and because the hollow end regions  416 ,  418  are expanded to fully fill the hex-shaped holes  426 ,  428 , good, secure, rotation resistant connections are formed that rigidly interconnect the side plates  402 ,  404  and that resist loosening and rotation of the bushings  406 ,  408  relative to the side plates  402 ,  404 . 
     Referring still to FIG. 1, the bushings  406 ,  408  are generally cylindrical, and provide stepped central regions that have relatively large diameter portions  436 ,  438  and relatively medium diameter portions  446 ,  448 , respectively. The end and central regions  416 ,  436 ,  446  of the bushing  406  are concentric about the transversely extending axis  456 . The end and central regions  418 ,  438 ,  448  of the bushing  408  are concentric about the transversely extending axis  458 . Optional internal threads (not shown) may be formed within hollow interiors of the bushings  406 ,  408  to permit threaded fasteners of suitable size (not shown) to be connected to the subassembly  400  (should this be desirable for some purpose). 
     Referring to FIGS. 1 and 2, the side plates  402 ,  404  define aligned first and second U-shaped notches  501 ,  502 , respectively, that open rearwardly with respect to a closure (not shown) on which the unit  100  is mounted so that, as the closure is moved toward its closed position, the resulting rearward movement of the side plates  402 ,  404  by the closure will cause the central region  56  of the strike  50  to be received within the first and second U-shaped notches  501 ,  502  (see FIGS.  9 - 11 ). Referring to FIGS. 1,  2 ,  7  and  9 , a cooperating third U-shaped notch  503  is formed in the rotary jaw  410 , and functions in concert with the first and second U-shaped notches  501 ,  502  to receive and latchingly retain the central region  56  of the strike  50  (shown in FIGS. 9-11) therein when the closure that mounts the unit  100  is closed. 
     The second U-shaped notch  502  (either alone or in concert with the first U-shaped notch  501 ) to define a strike engagement surface (or surfaces) that is (are) directly engageable by the central region  56  of the strike  50  (shown in FIGS.  9 - 11 ). If the first and second U-shaped notches  501 ,  502  are identically configured and positioned to extend in congruent alignment, a pair of congruently aligned strike engagement surfaces  492 ,  493  are defined by the notches  501 ,  502 —which are engageable by the central region  56  of the strike  50  as the central region  56  moves into and is latchingly retained within the U-shaped notches  501 ,  502 . If, on the other hand, the first U-shaped notch  501  is configured such that it is wider than the second U-shaped notch  502  (so that the surfaces that define the first notch  501  are positioned such that they cannot physically engage the strike  50 ), the only strike engagement surface that will be defined by either of the notches  501 ,  502  is the strike engagement surface  493  that is defined by the second U-shaped notch  502 . 
     By always ensuring that the strike engagement surface  493  is defined by the second U-shaped notch  502  (regardless of whether an additional strike engagement surface  492  is defined by the first U-shaped notch  501 ), advantage will always be taken of the close proximity presence to the second notch  502  (and to the strike engagement surface  493 ) of a transversely extending reinforcing flange  471  (see FIG. 2) that is formed integrally with the second side plate  404  near one end thereof. A tight radius bend  473  (see FIG. 1) connects the flange  471  to a narrow portion  475  (see FIGS. 1 and 2) of the second side plate  404  that extends along one side of the second notch  502  (and that defines the strike engagement surface  493 ). The close proximity presence of the transversely extending flange  471  and the bend  473  to the second notch  502  (and to the strike engaging surface  493  that is defined by the second notch  502 ) strengthens and rigidifies the second housing side plate  404  in the critical area adjacent the strike engaging surface  493 . 
     While the second U-shaped notch  502  could be configured such that it is wider than the first U-shaped notch  501  (whereby the only strike engagement surface that would be defined by either of the notches  501 ,  502  is the strike engagement surface  492  that is defined by the first U-shaped notch  501 ), this option does not conform to the preferred practice of the present invention unless the first side plate  402  is. provided with a transversely extending flange (not shown) that is substantially identical to the depicted flange  471 , but which extends from the first side plate  402  toward the second side plate  404  to bridge the space therebetween (instead of extending from the second side plate  404  toward the first side plate  402  to bridge the space therebetween, as does the depicted flange  471 ). 
     Referring to FIG. 1, housed between the side plates  402 ,  404  are the rotary jaw  410  and the rotary pawl  420 . The rotary jaw  410  has a mounting hole  411  that receives the bushing diameter  438  therein in a slip fit to mount the rotary jaw  410  on the bushing  408  for limited angular movement about the transversely extending axis  458 . The rotary pawl  420  has a mounting hole  421  that receives the bushing diameter  448  therein in a slip fit to mount the rotary pawl  420  on tile bushing  406  for limited angular movement about the transversely extending axis  456 . 
     Also housed between the side plates  402 ,  404  is a torsion coil spring.  480  that has a first coil  486  that extends about the diameter  436  of the bushing  406 , and a second coil  488  that extends about the diameter  438  of the bushing  408 . An end  481  of the spring  480  engages the rotary jaw  410  for biasing the rotary jaw  410  in a direction of angular movement about the axis  458  that is indicated by an arrow  485 . An opposite end  483  of the spring  480  engages the rotary pawl  420  for biasing the rotary pawl  420  in a direction of angular movement about the axis  456  that is indicated by an arrow  487 . 
     Referring to FIGS. 7-9, the rotary jaw  410  and the rotary pawl  420  are provided with engageable formations  413 ,  423 , respectively, that cooperate to “preliminarily latch” the rotary jaw  410  in engagement with the central region  56  of the strike  50  after the strike  50  has moved only a short distance into the aligned first and second U-shaped notches  501 ,  502  during movement of the closure toward its closed position. 
     The rotary jaw  410  and the rotary pawl  420  also are provided with engageable formations  415 ,  423 , respectively, that cooperate to “fully latch” the rotary jaw  410  in engagement with the central region  56  of the strike  50  after the strike  50  has moved as far as it is going to move into the aligned first and second U-shaped notches  501 ,  502  as the closure is moved to its fully closed position. When the engageable formations  415 ,  423  are engaged (as is depicted in FIG.  10 ), the rotary jaw  410  is prevented by the rotary pawl  420  from executing unlatching movement until the rotary pawl  420  is rotated about the axis  456  to a pawl-releasing position (this is effected when the second operating arm  300  is pivoted to bring the end region  278  into engagement with an operating formation or “trigger”  429  of the pawl, shown in FIG. 1, to cause the pawl  420  to pivot in opposition to tile action of the spring coil  488 ) wherein the engageable formations  415 ,  423  disengage to permit the rotary jaw  410  to rotate away from its fully latched position toward its unlatched position wherein the strike  50  is free to move out of the third U-shaped notch  503  that is defined by the rotary jaw  410 . This type of pawl-controlled jaw latching action is well known to those who are skilled in the art. 
     To move the rotary pawl  420  in opposition to the action of the torsion coil spring  480  (i.e., in a direction opposite the arrow  487 ) from a pawl-retaining position (depicted in FIGS. 10 and 11) to a pawl-releasing position (depicted in FIG.  7 ), the second operating arm  300  is pivoted (about the axis of the fastener  290  from the non-operated position depicted in FIG. 3 to the operated position depicted in FIG.  4 —which can only be done if the lock mechanism  200  has been operated to position the cam  210  in its unlocked position, as shown in FIG. 4) by operating the handle  150  (to pivot the handle  150  about the axis of the pin  156  from its normal non-operated position shown in FIGS. 1 and 5 to its operated position shown in FIG.  6 ). When the operated handle  150  is released, it returns to its non-operated position under the influence of the spring  282  (because the action of the spring  282  on the second operating arm  300  is transferred to the first operating arm  250  by the engagement of the driving formations  234 ,  272 , which, in turn, causes the stub shaft  152  to pivot the T-shaped handle grip  170  from its operated position to its non-operated position). 
     So long as the rotary jaw  410  of tile latch assembly  400  is in its unlatched position (depicted in FIG.  7 ), the rotary jaw  410  always can be slammed into latching engagement with the strike  50 . This is true regardless of how other relatively movable components of the unit  100  may be positioned. As the rotary jaw  410  receives the strike  50  within its third U-shaped notch  503 , and as the strike  50  moves into the aligned first and second IU-shaped notches  501 ,  502  of the housing side plates  402 ,  404 , the strike  50  becomes cooperatively confined by the combined action of the first, second and third notches  501 ,  502 ,  503 . When the strike  50  reaches the position that is depicted in FIG. 10, the rotary pawl  420  and the rotary jaw  410  become “preliminarily latched” (i.e., the engagement formations  413 ,  423  engage to prevent unlocking of the rotary jaw  410 ). When the strike  50  reaches the fully latched position depicted in FIG. 11, the engagement formations  415 ,  423  engage to fully lock the closure in its closed position. 
     So long as the key-locking assembly  200  positions the cam  210  in its “unlocked” position, as is depicted in FIGS. 4 and 6, pivotal movement of the second operating arm  300  will not be impeded by the cam  210 —hence, the operating handle  150  can be pivoted out of its nested, non-operated position (shown in FIG. 5) to its extended, operated position (shown in FIG. 6) to cause the projecting formation  175  to pivot the second operating arm  300  to engage the trigger  429  of the pawl  420  to pivot the rotary pawl  420  away from its normal jaw-retaining position (shown in FIG. 11) toward its jaw-releasing position (shown in FIG. 9) to release the pawl formation  423  from engaging either of the jaw formations  413 ,  415 , whereupon the rotary jaw  420  pivots under the influence of the spring  480  away from its latched position (shown in FIG. 11) to its unlatched position (shown. in FIG. 9) to release the strike  50 . 
     In operation, the T-handle grip  170  of the unit  100  can be pivoted between its nested position (shown in FIGS. 5 and 7) and its extended position (shown in FIGURES  6  and  8 ) regardless of whether the key lock assembly  200  is in its locked orientation (shown in FIGS. 2 and 3) or in its unlocked orientation (shown in FIG.  3 ). If the T-handle  150  is to be rotated about the axis  155  of the stub shaft  152  to operate the unit  100  to unlatch the latch assembly  400 , the T-handle grip  170  must be pivoted to its extended position (shown in FIG. 6) and the key lock assembly  200  must be operated to position the cam  210  in its unlocked orientation (shown in FIG. 3) so as to disengage the end region  276  of the second operating arm  300  so that the handle  150  can be rotated (as shown in FIGS. 6 and 8) to pivot the first and second operating arms  250 ,  300  from their non-operated positions (shown in FIGS. 2 and 3) to their operated positions (shown in FIG. 4) to cause the projecting end  278  of the second operating arm  300  to pivot the pawl  420  of the latch assembly  400  to release the rotary latch bolt  410  so that it will pivot under the influence of the spring  480  from the latched position (shown in FIG. 11) to the unlatched position (shown in FIG.  9 ). When the handle  150  is released (or when force applied to the handle  150  to rotate the handle  150  about the axis  155  is diminished sufficiently to permit the handle  150  and the operating arms  250 ,  300  to return to their non-operated positions under the influence of the spring  282 ), the spring  282  returns the handle  150  and the first and second operating arms  250 ,  300  to their non-operated positions. 
     If the latch assembly  400  is to be slammed into latched engagement with the strike  50  when the rotary latch bolt  410  is in the unlatched position shown in FIG. 9, preliminary latching, as depicted in FIG. 10, occurs before full latching, as depicted in FIG. 11, takes place. 
     Referring to FIGS. 12-13, a second latch embodiment incorporating features of the invention is indicated by the numeral  1100 . The second latch embodiment  1100  is substantially identical to the first latch embodiment  100  except that the latch assembly  1400  has a right angle bend in its side plate  1401  to differently orient the latch assembly  1400  with respect to the housing  1100 ; and except that the second operating arm  1300  has an extended end region  1268  with an operating formation  1278  that extends out over the bend in the side plate  1401  to engage the pawl  1420  of the repositioned latch assembly  1400 . 
     Inasmuch as the latch embodiments  100 ,  1100  have corresponding components that operate substantially identically, corresponding reference numerals that differ by a magnitude of one thousand have been used to identify corresponding components of the latch embodiments  1001   1100 . Thus, whereas the unit  100  consists of a housing  110 , an operating handle  150 , first and second operating arms  250 ,  300  and a latch assembly  400 , the unit  1100  consists of a corresponding housing  1110 , a corresponding operating handle  1150 , corresponding first and second operating arms  1250 ,  1300 , and a corresponding latch assembly  1400 , respectively. The use of these and other corresponding numerals that differ by a magnitude of one thousand eliminates the need to repeat the detailed description of features of the unit  100  (that appears earlier herein) to describe the unit  1100 , as those who are skilled in the art will readily understand. 
     Referring to FIGS. 15-16, a third latch embodiment incorporating features of the invention is indicated by the numeral  2100 . The third latch embodiment  2100  is substantially identical to the first latch embodiment  100  except that the housing  2110  of the third latch embodiment  2100  has a five-sided mounting flange  2120  that permits the key lock assembly  2200  to be repositioned to a location along the side wall  2123  of the housing  2100 ; except that the cam  2210  of the key lock assembly  2200  is differently configured to engage an end region  2266  of the second operating arm  2300  (which also is reconfigured to position the end region  2266  adjacent the cam  2210 ) with the key lock assembly  2200  being installed in the mounting flange  2110  rather than in a shallow portion of the recess defined by the housing  2110 ; and, except that the end region  2266  extends through a guide passage  2388  that is defined by the housing back wall portion  2132  and by a strap  2389  that overlies and has its end regions  2314  welded to the back wall portion  2132 . The strap  2389  serves to guide the movements of the second operating arm  2300 , and aids in supporting the second operating arm  2300  to resist deformation of the second operating arm  2300  during applications of undue force to the latch and lock unit  2100 . 
     Inasmuch as the latch embodiments  100 ,  2100  have corresponding components that operate substantially identically, corresponding reference numerals that differ by a magnitude of two thousand have been used to identify corresponding components of the latch embodiments  100 ,  2100 . Thus, whereas the unit  100  consists of a housing  110 , an operating handle  150 , first and second operating arms  250 ,  300  and a latch assembly  400 , the unit  2100  consists of a corresponding housing  2110 , a corresponding operating handle  2150 , corresponding first and second operating arms  2250 ,  2300 , and a corresponding latch assembly  2400 , respectively. The use of these and other corresponding numerals that differ by a magnitude of one or two thousand eliminates the need to repeat the detailed description of the unit  100  (that appears earlier herein) to describe the unit  2100 , as those who are skilled in the art will readily understand. 
     Referring to FIGS. 18-20, a fourth latch embodiment incorporating features of the invention is indicated by the numeral  3100 . The fourth latch embodiment  3100  is substantially identical to the third latch embodiment  2100  except that the latch assembly  3400  has a right angle bend in its side plate  3 . 401  to differently orient the latch assembly  3400  with respect to the housing  3100 ; and except that the second operating arm  3300  has an extended end region  3268  with an operating formation  3278  that extends out over the bend in the side plate  3401  to engage the pawl  3420  of the repositioned latch assembly  3400 . 
     Inasmuch as the latch embodiments  2100 ,  3100  have corresponding components that operate substantially identically, corresponding reference numerals that differ by a magnitude of one thousand have been used to identify corresponding components of the latch embodiments  2100 , = 3100 . Thus, whereas the unit  2100  consists of a housing  2110 , an operating handle  2150 , first and second operating arms  2250 ,  2300  and a latch assembly  2400 , the unit  3100  consists of a corresponding housing  3110 , a corresponding operating handle  3150 , corresponding first and second operating arms  3250 ,  3300 , and a corresponding latch assembly.  3400 , respectively. The use of these and other corresponding numerals that differ by a magnitude of one, two or three thousand eliminates the need to repeat the detailed description (that appears earlier herein) to describe the unit  3100 , as those who are skilled in the art will readily understand. 
     Such differences as exist among the components of the latch and lock embodiments  100 ,  1100 ,  2100 ,  3100  do not give. rise to fundamental differences in the way in which the embodiments  100 ,  1100 ,  2100 ,  3100  function—as will be readily apparent to those who are skilled in the art. 
     Each of the units  100 ,  1100 ,  2100 ,  3100  have in common the use of first (relatively short) and second (relatively long) independently pivoted operating arms ( 250 ,  300 ;  1250 ,  1300 ;  2250 ,  2300 ; and  3250 ,  3300 , respectively) that rotate through a relatively large range of angular movement (such as about thirty degrees) and a relatively small range of angular movement (such as about fifteen degrees), respectively, that have driving formations ( 234 ,  272 ;  1234 ,  1272 ;  2234 ,  2272 ; and  3334 ,  3372 , respectively) that engage when the their T-shaped operating handles (which are all identical to the described operating handle  150 ) are pivoted to cause operating arm movement (in the manner described in conjunction with the operating arms  250 ,  300 ) to trigger, release or unlatch their associated rotary latch assemblies  400 ,  1400 ,  2400 ,  3400 , respectively. 
     Each of the units  100 ,  1100 ,  2100 ,  3100  also have in common the use of stop formations  236 ,  1236 ,  2236 ,  3236  carried by their first operating arms  250 ,  1250 ,  2250 ,  3250  that engage tab-like extensions  390 ,  1390 ,  2390 ,  3390  of the latch assemblies  400 ,  1400 ,  2400 ,  3400  (wherein the tab-like extensions overlie and are rigidly connected to back wall portions  132 ,  1132 ,  2232 ,  3232  of the housings  110 ,  1110 ,  2110 ,  3110 ) to limit the reverse pivotal movement of the first operating arms  250 ,  1250 ,  2250 ,  3 . 250 , respectively. 
     Each of the units  100 ,  1100 ,  2100 ,  3100  also have in common the use of engagements between the first and second operating arms ( 250 ,  300 ;  1250 ,  1300 ;  2250 ,  2300 ; and  3250 ,  3300 , respectively) that cause the first and second operating arms to pivot concurrently in forward and return directions of angular movement about their separate pivot axes, and that limit the reverse pivotal movement of the second operating arms  300 ,  1300 ,  2300 ,  3300 . For the purpose of limiting the return direction pivotal movement of the second operating arms  300 ,  1300 ,  2300 ,  3300 , so-called “second stop surfaces” are defined by each of the first operating arms  250 , : 1250 ,  2250 ,  3250  that may take either or both of the forms of: 1) the drive formations  234 ,  1234 ,  2234 ,  3234  of the first operating arms  250 ,  1250 ,  2250 ,  3250  that are engaged by the drive formations  272 ,  1272 ,  2272 ,  3272  of the second operating arms  300 ,  1300 ,  2300 ,  3300 ; or 2) outer surface portions ( 242  and/or  244 ;  1242  and/or  1244 ;  2242  and/or  2244 ;  3242  and/or  3244  that are defined by the hubs  254 ,  1254 ,  2254 ,  3254  of the first operating arms  250 ,  1250 ,  2250 ,  3250 , respectively) that are engaged by adjacent surfaces  253 ,  1253 ,  2253 ,  3253  of the second operating arms  300 ,  1300 ,  2300 ,  3300 , respectively. 
     Referring, for example, to FIG. 3, it will be seen that the second operating arm has its drive formation  272  in stopped engagement with the drive formation  234  of the first operating arm  250  when the first operating arm  250  is stopped from further reverse movement by the engagement of its stop formation  236  with the tab-like extension  390  of the latch assembly  400 ; and that, at the same time, a surface  253  of the second operating arm  400  engages a rounded surface  242  defined by the hub  254 —with both of these engagements serving to stop further reverse pivoting of the second operating arm  300 . While one or both of these stopping types of engagement can be utilized, and while the use of either of these manners of stopping reverse direction pivotal movement of the second operating arm falls within the purview of the present invention, the concurrent use of both manners of stopping the reverse pivotal movement of the second operating arm may be desirable in some applications. 
     Referring, by way of another example, to FIG. 15, it will be seen that, while the second operating arm  2250  has a surface  2353  that could be configured to engage either or both of the surfaces  2242 ,  2244  of the hub  2254  (so that either or both of these engagements could be utilized to stop the return movement of the second operating arm when the first operating arm has its stop formation  2236  in engagement with the tab-like extension  2390  of the latch assembly  2400 ), the reverse pivotal movement of the second operating arm  2250  is, instead, stopped by the engagement of the operating formations  2234 ,  2272 . Sole or combined use of any of these types of stopping engagements between the first and second operating arms  2250 ,  2300  also is within the contemplated purview and scope of the present invention. 
     If it is desired, for some reason, to stop reverse direction pivotal movement of any of the described second operating arms before the reverse direction pivotal movement of the associated first operating arms are stopped (for example by engagement of the stop formation  236  with the tab-like formation  390 ), this can be accomplished by configuring the hub of the first operating arm (for example the hub  254 ) so that one or both of its outer surfaces (such as the surfaces  242 ,  244 ) is/are engaged by a surface of the second operating arm (such as the surface  253 ) before the stop formation of the first operating arm (such as the formation  236 ) engages the associated tab-like formation (such as the formation  390 ). This arrangement effectively provides for individualized stopping of the reverse direction pivotal movement of the first and second operating arms, and also is within the contemplated purview and scope of the present invention. 
     Thus, as will be seen from the foregoing description, taking into account the claims that follow, features of the present invention reside in the provision of a T-handle operating assembly for a rotary latch that includes the use of a pair of independently pivoted operating arms that drivingly interconnect the handle and the latch assembly, with the operating arms and reverse pivot stops being provided in a compact arrangement that, as a minimum, makes use of a tab-like extension of the side wall of a rotary latch housing as a stop for the first operating arm, and with a formation of the first operating arm also serving as a reverse pivot stop for the second operating arm. 
     As a comparison of the operating arms, as shown in FIGS. 3,  13 ,  16  and  19  will disclose, the units  100 ,  1100 ,  2100 ,  3100  also share the use of second operating arms  300 ,  1300 ,  2300 ,  3300  that are C-shaped in the sense that they wrap about half way around the hubs  254 ,  1254 ,  2254 ,  3354  of the first operating arms  250 ,  1250 ,  2250 ,  3350  to provide locations where the operating formations engage (i.e., where the formation  234  engages the formation,  272 ; where the formation  1234  engages the formation  1272 ; where the formation  2234  engages the formation  2272 ; and where the formation  3234  engages the formation  3272 ) that are located on opposite sides of the pivot axes of the first operating arms from the pivot axes of the second operating arms. By this arrangement, the second operating arms  300 ,  1300 ,  2300 ,  3300  have effective lengths (defined as the distances from their pivot axes to the locations where the operating formations engage) that are about twice as long as the effective lengths of the first operating arms  250 ,  1250 ,  2250 ,  3250  (defined as the distances from their pivot axes to the locations where the operating formations engage); and, the longer second operating arms pivot through smaller ranges of angular movement (typically about fifteen degrees) than do the shorter first operating arms (which pivot through ranges of about thirty degrees). What this arrangement provides is a means for reducing the relatively large angles of movement of the T-handles of the units  100 ,  1100 ,  2100 ,  3100  to provide what is needed in the way of smaller angular movements to better suit the range of angular movement that is better suit the limited amount of movement that needs to be effected by the extensions  278 ,  1278 ,  2278 ,  3278  of the second operating arms that cause the rotary latch pawls  420 ,  1420 ,  2420 ,  3420  to pivot to release of the rotary latch bolts  410 ,  1410 ,  2410 ,  3410  of the rotary latch assemblies  400 ,  1400 ,  2400 ,  3400 . 
     Stated in another way, the compact arrangement of operating arms that are of different length and that pivot through different ranges of movement is used advantageously herein to provide T-handle operated latches that permit their T-shaped operating handles to be pivoted through ranges of movement that are acceptable to those who utilize these units, while causing the second operating arms to diminish their ranges of movement so as to better accommodate the needs of the rotary latch assemblies that are employed, which require relatively little pawl movement to effect release of their rotary latch bolts. 
     Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example, and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed. It is intended that the patent shall cover, by suitable expression in the appended claims, whatever features of patentable novelty exist in the invention disclosed.

Technology Classification (CPC): 8