Mortise and multipoint latching assembly

In one form, a multipoint locking assembly includes a first latch device, a second latch device, and a mortise assembly coupled to the first and second latch devices. The mortise assembly may comprise a first transmission coupled to the first latch device via a first flexible member, a second transmission coupled to the second latch device via a second flexible member, and an actuation assembly operable to actuate the first and second transmissions. At least one of the transmissions comprises a slack removal device operable to remove slack in the flexible member to which it is coupled, thereby ensuring proper transmission of pulling forces between the transmission and the latch device.

TECHNICAL FIELD

The present invention generally relates to multipoint latching systems, and more particularly, but not exclusively, to multipoint latching systems where the latch operating system is concealed within the door.

BACKGROUND

Multipoint latching systems are often used to secure a door to a doorframe at multiple locations. Some such systems suffer from a variety of limitations, including those relating to aesthetics, ease of installation, adjustability, and other drawbacks. Therefore, a need remains for further improvements in multipoint latching systems.

SUMMARY

In one form, a multipoint locking assembly includes a first latch device, a second latch device, and a mortise assembly coupled to the first and second latch devices. The mortise assembly may comprise a first transmission coupled to the first latch device via a first flexible member, a second transmission coupled to the second latch device via a second flexible member, and an actuation assembly operable to actuate the first and second transmissions. At least one of the transmissions comprises a slack removal device operable to remove slack in the flexible member to which it is coupled, thereby ensuring proper transmission of pulling forces between the transmission and the latch device. Further embodiments, forms, features, aspects, benefits, and advantages of the present application shall become apparent from the description and figures provided herewith.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

As used herein, “inward” is the direction of retraction or actuation, and “outward” is the direction of extension. Lateral movement is movement in a lateral direction or substantially parallel to a lateral axis of the system, and longitudinal movement is movement in a longitudinal direction or substantially along a longitudinal axis of the system. As such, refraction or actuation of a laterally movable element is “laterally inward”, while retraction or actuation of a longitudinally movable element is “longitudinally inward”. In the embodiments illustrated herein, the lateral axis is a horizontal or substantially horizontal axis, and the longitudinal axis is a vertical or substantially vertical axis. In other embodiments, these orientations may be reversed, or the lateral and longitudinal axes may be offset from vertical and horizontal axes by oblique angles.

With reference toFIG. 1, an exemplary multipoint locking system100includes a mortise assembly110, a top latch device120, a bottom latch device130, an upper flexible connector (depicted herein as a cable140) connecting the top latch device120and the mortise assembly110, and a lower flexible connector (depicted herein as a cable150) connecting the bottom latch device130and the mortise assembly110. As described hereinafter, the exemplary flexible connectors comprise unidirectional force transfer members, such as pull cables140,150.

The exemplary mortise assembly110includes inner and outer handle assemblies112, a faceplate114, and a chassis200including a casing202. Each of the handle assemblies112includes a manual actuator, such as a handle115coupled to a spindle116, and may further include an escutcheon117and/or a spring cage118. In the illustrated form, the mortise assembly110is a lever-by-lever mortise assembly, wherein each of the handles115comprises a lever. It is also contemplated that one or both of the handles115may comprise another form of actuator, such as a knob. In other forms, one of the handle assemblies112may be omitted, such that, when installed, the system100is operable from only one side.

The top latch device120includes a coupling portion121configured to engage the upper cable140, a housing122, and a closure fastener such as a latch124movably coupled to the housing122. The top latch device120is operable in an extended or latching state wherein the top latch device120may secure the door in a closed position. In the latching state, the latch124is in an extended, latching position, wherein the latch124extends from the housing122and may engage a strike126, which may be mounted in a door frame. The top latch device120is also operable in a retracted or unlatching state, wherein the door may be opened. In the unlatching state, the latch124is in a retracted, unlatching position, wherein the latch124is positioned substantially or entirely within the housing122.

While other forms are contemplated, in the illustrated form, the movable coupling between the housing122and the latch124is a pivoting coupling, such that the top latch124pivots between the extended and retracted positions. The exemplary top latch124is a substantially U-shaped latch including a channel125, and the illustrative strike126includes a protrusion127configured to be received in the channel125. When the top latch124is in the retracted position and the door is open, the latch124is not engaged with the strike126. As the door is closed, the protrusion127engages the latch124, urging the latch to the extended position; when the door is fully closed, the protrusion127is seated in the channel125, and the top latch device120retains the door in the closed position.

In the illustrated form, the top latch device120further includes a blocking member128movably coupled to the housing122. The blocking member128is operable in an unblocking position wherein the top latch124may pivot from the extended position to the retracted position, and a blocking position wherein the blocking member128prevents the latch124from pivoting to the retracted position. The latch124may be biased toward the retracted position. For example, the latch124may be biased by a spring or by gravity such that, when the latch124is not engaged with the strike126and the blocking member128is in the unblocking position, the latch124moves toward the retracted position. When the latch124is in the retracted position, the blocking member128may be prevented from moving from the unblocking position to the blocking position. The top latch device120may further include a biasing member or spring129associated with the blocking member128, such that the blocking member128is biased toward the blocking position. In such forms, when the latch124transitions from the retracted position to the extended position, the blocking member128is urged toward the blocking position by the biasing force of the spring129.

As a result of the aforementioned features of the top latch124and the blocking member128, the illustrated top latch device120is operable in an unlatched state, a locked latched state, and an unlocked latched state. In the unlatched state, the latch124is in the unlatched or retracted position, and the blocking member128is retained in the unblocking position. In the unlocked latched state, the blocking member128is in the unblocking position, and the latch124is movable between the extended latching position and the retracted unlatching position. In the locked latched state, the blocking member128is in the blocking position, and the latch124is retained in the extended latching position.

In the illustrated form, the coupling portion121is connected to or integrally formed with the blocking member128such that, when the upper cable140is attached to the coupling portion121, the biasing force of the spring129is translated to the cable140. In other forms, the top latch device120may not necessarily include the spring129, for example in embodiments in which the coupling portion121is connected to or integrally formed with the top latch124.

The bottom latch device130includes a coupling portion131configured to engage the lower cable150, a housing132, and a closure fastener such as a bolt134movably coupled to the housing132. The bottom latch device130is operable in an extended or latching state wherein the bottom latch device130may secure the door in a closed position. In the latching state, the bolt134is in an extended or locking position, wherein the bolt134extends from the housing132. A strike136including a recess137may be mounted in a bottom portion of a door frame, such that when the door is closed and the bolt134is in the extended position, the bolt134is received in the recess137. The bottom latch device130is also operable in a retracted or unlatching state, wherein the bolt134is in a retracted or unlocking position. When in the unlocking position, the bolt134is positioned substantially or entirely within the housing132, and the door can be opened.

While other forms are contemplated, in the illustrated embodiment, the movable coupling between the bottom housing132and the bottom bolt134is a sliding coupling, such that the bottom bolt134moves substantially linearly between the extended and retracted positions. Additionally, the illustrated bottom latch device130includes deadlocking features138configured to prevent external forces from moving the bolt134from the extended position to the retracted position. The bottom latch device130may further include a biasing member or spring139associated with the bolt134, such that the bolt134is biased toward the extended position. In the illustrated form, the coupling portion131is an intermediate element coupling the lower bolt134and the lower cable150such that, when the lower cable150is attached to the coupling portion131, the biasing force of the spring139is translated to the cable150. In other forms, the bottom latch device130may not necessarily include the spring139, and the bottom bolt134may be biased toward the extended position by gravitational forces.

Each of the cables140,150comprises a first end portion142,152configured to engage the corresponding latch device120,130, and a second end portion144,154configured to engage the chassis200. For example, the first end portions142,152may comprise a coupling member such as a peg143,153, and the latch device coupling portions121,131may be configured to matingly engage the corresponding peg143,153. The second end portions144,154may comprise a coupling member such as a tab145,155and the chassis200may include features which matingly engage the corresponding tab145,155. As described in further detail below, the illustrated cables140,150are substantially identical bare cables, and may be utilized with any of a plurality of doors having varying dimensions.

In the illustrated embodiment, the upper cable140is coupled to the blocking member128by engagement of the coupling portion121and the peg143, and is biased longitudinally outward (i.e., in the direction of extension) by the spring129. As the cable140is retracted by the chassis200, the blocking member128is moved from the blocking position to the unblocking position, enabling the top latch124to pivot toward the retracted position. As the top latch124pivots from the retracted position to the extended position (for example, due to engagement with the strike126as the door is closed), the spring129urges the blocking member128toward the blocking position. As the blocking member128moves toward the blocking position, the cable140is pulled longitudinally outward, or toward the top latch device120. In other forms, the first end portion142may be coupled to another portion of the top latch device120, such as the top latch124.

In the illustrated embodiment, the lower cable150is coupled to the bottom bolt134, and is biased longitudinally outward (i.e., in the direction of extension) by the spring139. While in the illustrated form, the coupling portion131is an intermediate element between the bolt134and the lower cable150, it is also contemplated that the coupling portion131may be integrally formed with the bolt134, such that the bolt134is directly engaged with the peg153. As the cable150is retracted by the chassis200, the bolt134is pulled into the housing132toward the retracted position. With the bolt134in the retracted position, the spring139pulls on the cable150, urging the cable150longitudinally outward or toward the bottom latch device130.

In the illustrated form, the movable coupling between the top housing122and the top latch124is a pivoting coupling, while the movable coupling between the bottom housing132and the bottom bolt134is a sliding coupling. It is also contemplated that one or more of the movable couplings between the housings122,132and the respective closure fastener124,134may be of another form, such as a sliding coupling, a pivoting coupling, a rotary coupling, or a combination thereof. Additionally, one or more of the movable couplings may comprise a direct coupling between the housing122,132and the respective closure fastener124,134, or the coupling may be include intermediate elements.

With additional reference toFIG. 2, the chassis200includes an actuation assembly210operably coupled with the handles115, an upper transmission220connected to the top latch device120via the upper cable140, and a lower transmission230connected to the bottom latch device130via the lower cable150. Each of the illustrated transmissions220,230includes a bell crank240coupling the actuation assembly210to the corresponding transmission220,230, and a slack removal device or spool assembly300coupling the transmissions220,230to the corresponding cable140,150. As described in further detail below, the chassis200may further include a hold-open assembly400configured to prevent one of the latch devices120,130from prematurely transitioning from the retracted state to the extended state.

In the illustrated form, the chassis200is configured to translate a rotational input (e.g., of the handles115) to longitudinal (e.g., vertical) movement of the transmissions220,230. It is also contemplated that the chassis200may be configured to cause longitudinal movement of the transmissions220,230in response to another form of input. The input may be a mechanical input, such as a linear or pivotal motion of an actuator, which may be performed manually. In other forms, the input may be an electrical input such as a command or signal, and the chassis200may comprise an electrical or electromechanical actuator which moves the transmissions220,230in response to the electrical input.

As described in further detail below, during operation of the exemplary system100, rotation of either of the handles115actuates the actuation assembly210, which urges the transmissions220,230toward one another. As the upper and lower transmissions220,230move toward one another, the cables140,150are pulled toward the chassis200, urging the blocking member128toward the unblocking position, and urging the bottom bolt134toward the retracted position.

The exemplary actuation assembly210includes a hub211rotationally coupled with at least one of the spindles116, a pawl212rotationally coupled with the hub211, a drive rod213including a head214, and a bracket215positioned on the drive rod213adjacent to the pawl212. The assembly210further comprises a clevis216, which is positioned adjacent to the drive rod head214. The clevis216may include an opening217through which the drive rod213extends. During assembly, the drive rod213may be passed through the opening217, and the head214may be attached to the drive rod213such that lateral motion of the drive rod213causes a corresponding lateral motion of the clevis216. The clevis216is coupled to the upper and lower bell cranks240, for example via rivets or pins218. The actuation assembly210may further comprise a biasing device219engaged with the pawl212, such that the pawl212is biased toward an extended or unactuated position.

The upper transmission220includes an upper link plate222slidingly coupled to the casing202, a bell crank240coupling the clevis216and the link plate222, and a spool assembly300coupled to the link plate222and the upper cable140. The lower transmission230is substantially similar to upper transmission220, and includes a lower link plate232slidingly coupled to the casing202, a bell crank240coupling the clevis216and the link plate232, and a spool assembly300coupled to the link plate232and the lower cable150. The upper link plate222may include an upper link plate channel224, and the lower link plate232may include a lower link plate channel234.

Each of the bell cranks240is pivotally mounted to the casing202, for example by a pivot pin242, and is configured to translate lateral (e.g., horizontal) motion of the clevis216to longitudinal (e.g., vertical) motion of the corresponding link plate222,232. The bell cranks240include a first portion or arm244engaged with the corresponding link plate222,232, and a second portion or arm246engaged with the clevis216. The engagement between the link plates222,232, the bell cranks240, and the clevis216may comprise lost motion connections. For example, the first arm244may include a rivet or pin245extending into the corresponding link plate channel224,234, forming a lost motion connection between the bell cranks240and the corresponding link plates222,232. The second arm246may include a channel247into which one of the clevis pins218extends, forming a lost motion connection between the bell cranks240and the clevis216.

The exemplary spool assemblies300include a housing310, a spool320received in the housing310, an adjustment device330operable to selectively rotate the spool320, and a retaining device340operable to selectively prevent rotation of the spool320. Each of the spools320is coupled to the corresponding cable140,150, such that each of the latch devices120,130is operably connected to the corresponding transmission220,230.

FIGS. 3aand 3bdepict the spool assembly300of the upper transmission220, along with a portion of the upper cable140. For purposes of clarity, the housing310is not depicted. While the following description is made with reference to the upper spool assembly300and the upper cable140, it is to be appreciated that the elements and features described hereinafter are equally applicable to the lower spool assembly300and lower cable150.

The spool320includes a substantially circular cylindrical body321, which may include a cutout322configured to receive the tab145and an opening323having a width corresponding to the diameter of the cable140. In such forms, the cable140may be coupled to the spool assembly300by positioning the tab145in the cutout322such that the cable140extends through the opening323. The spool320may then be rotated, such that the second end portion144is wound onto the spool320, while the first end portion142remains free. In other words, the first end portion142may comprise a free portion of the cable140which is not wound about the spool320, and the second end portion144may comprise a wound or spooled portion of the cable140which is wound onto the spool320. The spool320may further include a helical channel324configured to receive the cable140when the second end portion144is wound onto the spool320. The illustrated spool320further includes gear portion326comprising a plurality of radially extending gear teeth327.

The exemplary adjustment device330comprises a worm332including threads333, and a head334coupled to the worm332, for example through a slip clutch336. The threads333are meshingly engaged with the teeth327, such that rotation of the worm332causes the spool320to rotate as the threads333urge the teeth327in a direction corresponding to the rotational direction of the worm332. In the illustrated form, the distal end of the worm332includes a lobed portion338including a plurality of angularly spaced cams or radial lobes339. The head334may include an engagement feature such as a hex opening335through which a user with an appropriate adjustment tool may rotate the head334. The head334may be aligned with an opening203in the side of casing202(FIG. 2), such that the head334is accessible through the opening203when the faceplate114is not installed.

Rotation of the spool320in a tightening direction may cause the cable140to wind onto the spool320, while rotation of the spool320in a loosening direction may cause the cable140to unwind from the spool320. Thus, a user can adjust the effective length of the cable140(that is to say, the length of the free portion or first end portion142, which is not wound onto the spool320) by rotating the worm332in the appropriate direction. As will be appreciated, if the spool320were to rotate in the loosening direction after installation of the system100, the cable140would slacken, risking malfunctioning of the system100. To mitigate such risk, the spool assembly300includes the retaining device340, which retains the spool320in the rotational position selected by the user.

The retaining device340is configured to selectively retain the worm332in a plurality of discrete rotational positions. In the illustrated form, the retaining device340includes a retaining member342and a biasing member in the form of a spring344. The retaining member342is positioned in the housing310adjacent to the lobed portion338, and the spring344urges the retaining member into contact with the lobed portion338.FIG. 3billustrates the spool assembly300with the worm332in one of the discrete rotational positions and the retaining member342in a first position, to which it is biased by the spring344. In the first position, the retaining member342engages two of the lobes339.

When the worm332is rotated, a leading edge of one of the lobes339engages the retaining member342and urges the retaining member342away from the first position against the force of the spring344. As the worm332continues to rotate, the retaining member342travels along the lobe339from the leading edge to a radial apex of the lobe339, at which point the retaining member342is in a second position. Continued rotation of the worm332causes the retaining member to travel from the apex to a trailing edge of the lobe339, at which point the biasing force of the spring344urges the worm332to the next discrete position.

As will be appreciated, in order to rotate the worm332, the torque applied thereto must be sufficient to urge the retaining member342away from the first position against the biasing force of the spring344. When a sufficient torque is applied to the worm332, the worm332rotates, and the retaining member342reciprocates between first and second positions as it travels along the lobes339. In the absence of such a torque, the retaining device340prevents rotation of the worm332from the discrete rotational position, thereby preventing rotation of the spool320, and maintaining the cable140at the effective length selected by the user.

As will be appreciated, the illustrated lobed portion338comprises four lobes339, defining four discrete rotational positions of the worm332. It is also contemplated that the lobed portion338may comprise more or fewer cams or lobes339, resulting in a corresponding number of discrete rotational positions. It is further to be appreciated that the amount by which the effective length of the cable140is adjusted by rotation of the worm332from one discrete position to the next depends upon a number of factors, such as the angular offset between each of the discrete positions, the pitch of the threads333, and the relative radii of the gear portion326and the worm332. One having skill in the art will therefore may provide appropriate tolerances for slack in the cable140by appropriate consideration of these factors.

With additional reference toFIG. 4, the illustrated chassis200also includes a hold-open assembly400including a tilting link410which is pivotal with respect to the casing202. The tilting link410is operable in a first, holding position and a second, releasing position. The tilting link410includes upper arm420engaged with the upper transmission220, and a lower arm430engaged with the lower transmission230. The hold-open assembly400may further include a biasing assembly440including a biasing element such as a spring442configured to bias the tilting link410toward the holding position.

The upper arm420includes an opening422comprising a channel424, an enlarged portion426, and a cam surface such as a ramp428. The upper link plate222may include a rivet or pin226extending into the opening422. The lower arm430includes an opening432comprising a channel434, an enlarged portion436, and a ledge438. The lower link plate232may include a rivet or pin236extending into the opening432. Further features and details regarding the hold-open assembly400and the functions thereof are described below.

FIG. 5depicts the illustrative multipoint latching system100along with a door assembly500. The door assembly500comprises a door510including a cutout520, and a door frame530to which the door520is pivotally mounted. When installed, the system100is operable to selectively retain the door510in a closed position within the frame530by operation of the mortise assembly110and latch devices120,130.

The door510comprises a proximal narrow vertical edge or proximal side511, an upper surface or top512, a lower surface or bottom513, an inner broad side or inner face514, an outer broad side or outer face515, a distal narrow vertical edge or distal side516, and one or more hinges517mounted near the distal side516. In the illustrated form, the door510is a wood door, although other forms are contemplated. As will be appreciated by those having skill in the art, the term “wood door” is an industry-accepted term which is used with reference to doors which appear to be made of wood. In contrast, a “steel door” is a door substantially or entirely formed of steel or another metal. Generally, steel doors are substantially hollow, while wood doors are substantially solid. While a wood door may be formed entirely or substantially entirely of wood, the term also encompasses doors which have wooden panels or veneers on at least some of the visible surfaces, while at least a portion of the body of the door is formed of another type of material such as a composite.

In the illustrated form, the wood door510includes an inner core comprising a composite518, and at least one of the visible surfaces (such as the inner and outer faces514,515) includes a veneer or panel519. The composite518may, for example, be a fire-retardant composite such as a fire-rated plywood, such that the door510may be fire-rated. In the illustrated form, the bulk of the door510is formed of the composite518, and the panel519comprises a veneer, which is relatively thin in comparison to the width of the door510. In other forms, the composite518may be relatively thin in comparison to the width of the door510, and the panel519may comprise a greater width than the composite518.

The cutout520includes a center opening521formed in the proximal side511, an upper opening522formed in the door top512, a lower opening523formed in the door bottom513, an upper channel524connecting the center opening521and the upper opening522, and a lower channel525connecting the center opening521and the lower opening523. In the illustrated form, the channels524,525are substantially enclosed within the door510. That is to say, the channels524,525are circumferentially surrounded by the composite518. In certain forms, the channels524,525may be formed by boring into the door510through the top512and/or the bottom513. In other forms, the channels524,525may be formed by milling a ravine into the door510through the proximal side511and subsequently sealing off at least a portion of the ravine, for example with the composite518, panel519, or another material. In further embodiments, the channels524,525may not necessarily be enclosed within the door510, and may, for example, comprise ravines formed in the proximal edge511.

The illustrated frame530includes a proximal side531, a top portion532, a floor533adjacent the door bottom513, and a distal side536adjacent the door distal side516. The top strike126may be mounted in a recess formed in the top portion532, and the bottom strike136may be mounted in a recess formed in the floor533. When the door510is closed, the door proximal side511is adjacent the frame proximal side531, and the door top512is adjacent the frame top portion532.

With continued reference toFIGS. 1-5, an illustrative method of installing the multipoint locking system100in the door assembly500will now be described. The installation may begin by positioning the door510on a working surface such that the door inner and outer sides514,515are substantially horizontal, and threading the cables140,150through the cutout520. The cables140,150may comprise a total length greater than the length of the corresponding channels524,525such that, when the cables140,150are threaded through the cutout520, the end portions142,144,152,154are positioned outside of the cutout520. For example, the upper cable first end portion142may extend longitudinally out of the door510from the upper opening522, and the upper cable second end portion144may extend laterally out of the door510from the center opening521.

The first end portions142,152may then be coupled to the corresponding latch devices120,130, for example by engaging the pegs143,153with the respective coupling portions121,131. Additionally, the second end portions144,154may be coupled to the mortise assembly110, for example by seating the tabs145,155in the spool cutouts322. Because the cables140,150extend out of the door510, the cables140,150may be coupled to the mortise assembly110and the corresponding latch devices120,130outside the confines of the cutout520, facilitating installation.

When the cables140,150are coupled to the corresponding latch devices120,130and spool assemblies300, each of the cables140,150comprises an effective length corresponding to the length of the cable140,150between the spool assembly300and the corresponding latch device coupling portion121,131. After the cables140,150are connected to the mortise assembly110and corresponding latch devices120,130and spool assemblies300, the top latch device120is inserted into the upper opening522, the bottom latch device130is inserted into the lower opening523, and the chassis200is inserted into the center opening521. The latch devices120,130and chassis200may then be secured to the door510using appropriate fasteners.

Once the latch devices120,130and chassis200are seated in their respective openings, the cables140,150may comprise a certain amount of slack. That is to say, the effective lengths of the cables140,150may be greater than the longitudinal distance between the spool assembly300and the corresponding latch device coupling portion121,131. Thus, the installation method may further comprise removing the slack by adjusting the effective lengths of the cables140,150using the adjustment devices330. The adjusting may include inserting an adjustment tool such as an Allen wrench into the hex opening335through the chassis opening203, and rotating the head334in the tightening direction. As the worm332rotates in the tightening direction, the cable140or150winds onto the corresponding spool320, which removes slack from the cable by decreasing the effective length thereof.

As should be appreciated, the slack-removing spool assemblies300allow a user to adjust the effective length of the cables140,150to correspond to the distance between the mortise assembly110and the latch devices120,130without having to change or modify the total lengths of the cables140,150. As such, the multipoint locking system100can be utilized with varying positions of the mortise assembly110with respect to the latch devices120,130, as well as on doors510of different heights. In other words, a system100including a single set of cables140,150can be used on any of a plurality of doors510having different heights and different positions of the mortise assembly110.

Over-tightening of the cables140,150may cause damage to one or more elements of the system100. To prevent such damage, the illustrative adjustment device330includes a slip clutch336configured to limit the amount of torque transmitted from the head334to the worm332. Once the cables140,150comprise the appropriate effective lengths, they become taut. If the installer continues to rotate the head334when the cables140,150are taut, the clutch336may begin to slip, preventing additional rotation of the worm332in the tightening direction and over-tightening of the cables140,150.

When the cables140,150have been adjusted to the appropriate effective length, the retaining devices340retain the spools320in the selected rotational position as described above, preventing inadvertent adjustment of the effective lengths of the cables140,150. While the illustrated spool assembly300maintains the rotational position of the spool320via engagement of the lobed portion338and the retaining member342, it is also contemplated that that the spool320may be selectively prevented from rotating in another manner. For example, the spool assembly300may include a ratchet device (not illustrated) which allows rotation of the spool320in the tightening direction, and prevents rotation of the spool320in the loosening direction. In other forms, the head334may be axially movable between an unlocked position wherein rotation of the worm332is permitted and a locked position wherein rotation of the worm332is prevented, and the head334may be biased to the locked position. In such forms, the user may have to push the head334to the unlocked position (for example using the adjustment tool) prior to rotating the head334.

Once the cables140,150become taut, the faceplate114may be secured to the door proximal side511, sealing off the chassis openings203and enclosing the chassis200in the center opening521. The door510may then be mounted in the frame530, and the inner and outer handle assemblies112may be coupled to the chassis200to complete installation of the multipoint latching system100. It may be the case that the effective length of one or both of the cables140,150needs to be adjusted, for example due to faulty installation, or changing operating conditions. In such a case, the faceplate114can be removed to expose the adjustment assemblies330, and the effective lengths of the cables140,150can be adjusted in situ.

With continued reference toFIGS. 1-5, an illustrative method of operating the multipoint locking system100and the door assembly500will now be described. When installed, the multipoint latching system100is operable in a latched configuration wherein the latch devices120,130are in extended or latching states, and an unlatched configuration wherein the latch devices120,130or in retracted or unlatching states. Within the latched configuration, the system100is operable in a locked latched configuration wherein the latch devices120,130are retained in their latched states and the door510cannot be opened, and an unlocked latched configuration wherein the latch devices120,130can be moved to their retracted states to open the door510.

In the locked latch configuration, the chassis200is in an unactuated, extended, or locking state (FIGS. 2 and 4). As a result, the top latch device120is in the locked latched state wherein the blocking member128prevents the top latch124from moving to the unlatched position. In the unlocked latched configuration, the chassis200is in an actuated, retracted, or unlocking state (FIG. 6). As a result, the top latch device120is in the unlocked latched state wherein the blocking member128does not prevent the top latch124from moving to the unlatching position. As described in further detail below, when the system100is in the unlatched configuration, the hold-open assembly400retains the chassis200in the actuated or unlocking state.

With specific reference toFIGS. 2 and 4, when the chassis200is in the locking state, each of the transmissions220,230is in an extended, unactuated, or locking state, wherein the spool assemblies300are positioned adjacent to upper and lower edges204,205of the casing202. With the chassis200in the locking state, actuation of one of the handles115rotates the corresponding spindle116, causing the hub211and the pawl212to rotate. As the pawl212rotates, it engages the bracket215, urging the drive rod213toward a retracted position, or laterally inward. As the drive rod213retracts, the head214pulls the clevis216laterally inward (i.e., toward the hub211in a lateral direction). As the clevis216moves laterally inward or retracts, the pins218pull the bell crank second arms246laterally inward, causing the bell cranks240to rotate.

As the bell cranks240rotate, the first arms244retract the link plates222,232. That is to say, the link plates222,232are moved longitudinally inward, or toward one another, in response to laterally inward motion or retraction of the clevis216. In the illustrated form, the chassis200translates lateral motion of the clevis216to longitudinal motion of the link plates222,232via the rotating or pivoting bell cranks240. It is also contemplated that the chassis200may include alternative features to accomplish this task. For example, the rotating bell cranks240may be replaced by a sliding plate including a cam surface such as a diagonal slot, and the link plates222,232may include rivets or pins extending into the diagonal slot.

Refraction or longitudinally inward motion of the link plates222,232causes corresponding longitudinally inward motion of the spool assemblies300and the cables140,150. Thus, by actuating one of the handles115, a user can transition the chassis200from the locking state to the unlocking state. While other forms are contemplated, in the illustrated form, longitudinal movement comprises vertical movement of the spool assemblies300. Movement in the longitudinally inward direction comprises downward movement of the upper spool assembly300and upward movement of the lower spool assembly300, and movement in a longitudinally outward direction comprises upward movement of the upper spool assembly300assembly and downward movement of the lower spool assembly300. It is noted that, during retraction of the spool assemblies300, the spools320maintain a substantially fixed rotational position, and rotate only to adjust the effective lengths of the cables140,150. In other words, each of the spool assemblies300is movable in a first manner (i.e., rotation of the spools320) to remove slack in the corresponding cable140,150, and is movable in a second manner (i.e., in a longitudinally inward direction) to retract the cable140,150to which it is attached.

As the upper cable140retracts, the blocking member128is moved to the unblocking position, such that the top latch device120is in the unlocked latched state. As the lower cable150retracts, the bottom bolt134is pulled upward to the retracted position, such that the bottom latch device130is in the unlatched state. That is to say, when the chassis200reaches the unlocking state (FIG. 6), the top latch124is free to move to the retracted position, the bottom bolt134is in the retracted position, and the door510may be opened.

As the door510is opened, the top latch124moves out of engagement with the top strike126and toward the retracted position, for example due to engagement with the protrusion127, the biasing force of a spring or gravity. Thus, when one of the handles115is actuated and the door510is open, each of the latch devices120,130is in the retracted state. If the door510is closed while the handle115remains actuated, the top strike126urges the top latch124to the extended position, such that the top latch device120is in the unlocked latched state. If the handle115is then released, the top spring129urges the blocking member128to the blocking position, and the bottom spring139urges the bottom bolt134to the extended position. As a result, the system100transitions to the locked latched configuration, and the chassis200transitions to the unactuated or locking state as the springs129,139urge the transmissions220,230longitudinally outward via the cables140,150.

If the user releases the handle115with the door510open, the spring cages118may urge the handle115to an unactuated or home position, and the biasing device219may urge the pawl212to the corresponding unactuated or home positions depicted inFIG. 2. When this occurs, the drive rod213no longer retains the clevis216in the retracted position, and the clevis216no longer counteracts the longitudinally outward biasing forces provided by the springs129,139. As a result, the transmissions220,230are urged longitudinally outward.

If the lower transmission230were to move longitudinally outward while the door510is open, the bottom bolt134would extend out of the housing132and strike the floor533, which may damage the bolt134and/or the floor533. Additionally, the bolt134may drag along the floor533as the user opens or closes the door510, which may cause additional damage. In the illustrated embodiment, however, the hold-open assembly400retains the bottom bolt134in the retracted position until the top latch124returns to the extended position.

With continued reference toFIGS. 1-6, the operation of the hold-open assembly400will now be described. When the chassis200is in the unactuated or locking state (FIG. 4), the tilting link410is in the releasing position, the upper link plate pin226is positioned in the upper channel424, and the lower link plate pin236is positioned in the lower channel434. When the actuation assembly210is actuated, the chassis200transitions to the unlocking state (FIG. 6) as described above. As the transmissions220,230retract to the respective actuated or unlocking states, the link plate pins226,236move longitudinally inward from the channels424,434to the enlarged portions426,436, and the biasing assembly440urges the tilting link410toward the holding position (FIG. 6). In other words, the tilting link410is operable in the holding position in response to the actuated or unlocking state of the transmissions220,230.

As best seen inFIG. 6, when the chassis200is in the actuated or unlocking state and the tilting link410is in the holding position, the upper link plate pin226is positioned in the upper enlarged portion426adjacent the ramp428, and the lower link plate pin236is positioned in the lower enlarged portion436adjacent the ledge438. When the handle115is released, the transmissions220,230are urged longitudinally outward under the biasing force of the springs129,139.

If the handle115is released when the latch124is in the extended/latching position (e.g., when the door510is closed), the top spring129moves the blocking member128toward the blocking position, pulling the upper transmission220longitudinally outward (e.g., upward) to the unactuated or locking state. As the upper link plate222moves longitudinally outward, the upper link plate pin226engages the ramp428, urging the tilting link410toward the releasing position. In other words, the tilting link410is operable in the releasing position in response to the unactuated or locking position of the upper transmission220. Stated another way, the hold-open assembly400is operable in the releasing position in response to the locked latched state of the upper latch device120. As the tilting link410moves toward the releasing position, the ledge438is moved out of alignment with the lower link plate pin236, and the lower channel434is moved into alignment with the pin236. The pin236is thus free to travel along the channel434, and lower link plate232is free to move longitudinally outward (e.g., downward) under the biasing force of the lower spring139. In other words, when the tilting link410is in the releasing position, the lower transmission230is movable from the unlocking state to the locking state, and the bolt134is movable between the unlocking and locking positions.

If the handle115is released when the door510is open, the blocking member128is prevented from moving to the blocking position. Thus, the upper cable140and upper transmission220will not be pulled longitudinally outward to the locking position, despite the biasing force of the spring129. The upper link plate pin236therefore remains in the upper enlarged portion426, and does not urge the tilting link410to the releasing position as described above. As a result, the ledge438remains aligned with the lower link plate pin236. As the biasing force of the lower spring139urges the lower transmission230longitudinally outward, the lower link plate pin236engages the ledge438, preventing further extension of the lower transmission230. That is to say, when the tilting link410is in the holding position, the lower transmission230is retained in the actuated or unlocking state. Thus, the bottom bolt134will remain in the retracted position when the door510is open, and will not drag along the floor533as the door510moves.

While certain conventional multipoint latch systems may provide hold-open assemblies which achieve similar results, such systems often require additional elements in the top latch devices and/or direct connection between the top latch device and the bottom latch device. Additional elements often increase the size of the latch devices, and direct connections between the latch devices require additional connecting members. In either case, the cutout in the door must be enlarged to accommodate the enlarged latch devices and/or additional connecting members, decreasing the structural integrity of the door. The illustrated system100, however, may not necessarily require additional features in the latch devices120,130, and may require only a single connection between the top latch device120and the mortise assembly110(e.g., the upper cable140), and a single connection between the bottom latch device130and the mortise assembly110(e.g., the lower cable150). Furthermore, the tilting link410may comprise a relatively thin width, and may not necessarily increase the overall width of the chassis200by an appreciable amount.

As can be seen from the foregoing, during operation of the illustrated system100, the flexible connectors (e.g., cables140,150) need only transmit pulling or tensile forces, and need not transmit pushing or compressive forces. As such, the cables140,150may be bare cables. As will be appreciated by those of skill in the art, the term “bare cable” does not preclude the use of a protective coating on the cable, but rather is used to distinguish from Bowden or push-pull cables, which are sheathed or enclosed.

While the illustrated flexible connectors comprise bare upper and lower cables140,150, it is also contemplated that one or more of the cables may comprise any form of unidirectional force transfer member, such as a chain, tether, or rope. Additionally, in certain forms, the system100may comprise a single flexible member, for example if only one of the latch devices120,130is utilized. In further forms, the system100may include each of the latch devices120,130, and one of the latch devices120,130may be connected to the mortise assembly110via a unidirectional force transfer member such as a pull cable, while the other of the latch devices120,130may be connected to the mortise assembly110via a bidirectional force transfer member such as a Bowden cable or a rigid member.

As should be appreciated, the cables140,150constitute non-rigid mechanisms for causing movement of the latch devices120,130in response to actuation of the handles115. As should also be appreciated, the adjustment device330can be accessed with the cables140,150installed in the door510(i.e., without having to remove the spool320or the cables140,150), thereby allowing for convenient adjustment of the multipoint latching system100while the door510is mounted to the door frame530. Additionally, the distance between the latch devices120,130and the mortise assembly110does not directly affect the functionality of the system100, and interconnection of the mortise assembly110and the latch devices120,130does not require a direct line of sight and/or precise alignment. Thus, the mortise assembly110and the latch devices120,130may have different backsets from the door proximal side511and/or from the door inner and outer sides514,515. Furthermore, in view of the flexible and non-rigid nature of the system100(i.e., the flexibility and non-rigidity provided by the cables140,150), if the latch devices120,130and/or the mortise assembly110are displaced from their installed locations, the system100does not necessarily require re-adjustment. Instead, the flexible and non-rigid nature of the system100can alleviate or at least minimize the need for re-adjustment of the latch devices120,130and/or the mortise assembly110. Moreover, the flexible cable system is easy to install or remove from the door510, even in instances where the door510is installed with a low ceiling clearance. The cable system also provides for direct attachment of the latch devices120,130to the hold-open assembly400, thereby removing or at least minimizing tolerances from the hold-open function and allowing a cable-based system to control operation of the lower latch device130. Additionally, concealment of the cables140,150within the door510results in a more aesthetic system, serves to protect the internal components and interconnections, and provides an added degree of security by eliminating potential tampering.