LATCH MODULE

Abstract

A latch module for selectively engaging into a striking plate of doorjamb, including at least a housing, a latch bolt, a guard bolt, and a stem for retracting the latch bolt is particularly versatile, safe and has low manufacturing costs, if the stem is movably supported relative to the latch bolt and if the stem has a block for entraining the latch bolt, if the stem reaches a first intermediate position while being moved from the stem's closed position towards the stem's open position.

Claims

1. A latch module configured to selectively engage a striking plate of a door jamb and comprising at least a housing, a latch bolt, a guard bolt, a blocking member, and a stem, wherein the latch module has a first end and a second end, wherein the first end is configured to face towards the door jamb and the second end is configured to extend into a mortise of a door, the housing movably supports the latch bolt and the guard bolt, the latch bolt has a latch bolt extended position and a latch bolt retracted position, and the guard bolt has a guard bolt extended position and a guard bolt retracted position, and each of the latch bolt and the guard bolt is being biased into a respective corresponding extended position, the stem has a stem longitudinal axis and is movably supported relative to the housing, the stem having a stem closed position and a stem open position, the stem is movably supported relative to the latch bolt, the stem has a stem block configured to entrain an abutment of the latch bolt when the stem reaches a first intermediate position while being moved from the stem closed position towards the stem open position, the blocking member is movably supported between a blocking position and a released position, and wherein the blocking member is configured to block a retraction of the latch bolt, when the blocking member is in the blocking position and to release said block of the retraction of the latch bolt, when the blocking member is in the released position, the guard bolt is configured to maintain the blocking member in the released position, when the guard bolt is in the guard bolt extended position, wherein (i) the blocking member includes a first leg and a second leg, (ii) a front-end portion of the first leg is connected by a front hinge to the latch bolt, wherein the front hinge defines a front hinge axis, (iii) a rear end of the second leg is connected by a rear hinge to the housing, wherein the rear hinge defines a rear hinge axis, p1 (iv) the front hinge axis and the rear hinge axis define a plane, (v) a rear-end portion of the first leg and a front-end portion of the second leg are connected by a middle hinge, wherein the middle hinge defines a middle-hinge axis, wherein the middle-hinge axis is on a first side of the plane when the blocking member is in the blocking position and on an opposite side of the plane when the blocking member is shifted to the released position, (vi) the front leg and the rear leg define an angle a therebetween, wherein when the blocking member is in the blocking position α.sub.min≤α≤180°, and when the blocking member is in the released position α>180°, wherein α.sub.min∈[90°,180°[, α.sub.min=const.

2. The latch module of claim 1, characterized in that (i) the latch bolt has a first end and a second end, (ii) the second end of the latch bolt has a recess that is delimited at least in part by at least one bearing surface, (iii) a first end of the stem extends into the recess, and (iv) the bearing surface is configured to support the stem substantially perpendicularly, within ±15°, to the stem longitudinal axis and further configured to enable a translation of the stem along the stem longitudinal axis and relative to the bearing surface delimiting at least a portion of the recess, said translation being delimited by the stem block and the abutment of the latch bolt.

3. The latch module of claim 1, characterized in that the guard bolt has a guard bolt abutment that faces the latch bolt and the latch bolt has a latch bolt block that faces the guard bolt and that the latch bolt block is configured to contact the guard bolt abutment when the latch module is entrained by the stem towards the latch bolt retracted position.

4. The latch module of claim 1, characterized in that the guard bolt in the guard bolt extended position maintains the blocking member in the released position, and in that the guard bolt in the guard bolt retracted position provides space for the blocking member to be shifted into the blocking position.

5. The latch module of claim 1, characterized in, that (i) the stem includes a releasing member, (ii) the releasing member is positioned to entrain the blocking member from the blocking position into the released position when the stem is moved from the stem closed position into a second intermediate position, while the guard bolt is in the guard bolt retracted position.

6. The latch module of claim 5, characterized in that the second intermediate position is in between the stem closed position and the first intermediate position.

7. The latch module of claim 1, characterized in that α.sub.min is defined by a block of the front leg abutting the rear leg at α=α.sub.min, and/or α.sub.min is defined by a block of the rear leg abutting the front leg at α=α.sub.min , and/or at least one of the front leg and the rear leg abuts the housing or the guard bolt in the guard bolt retracted position at α=α.sub.min.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In the following, the invention will be described by way of example, without limitation of the general inventive concept, on examples of embodiment and with reference to the drawings.

[0029] FIG. 1 shows two perspective views of a latch module,

[0030] FIG. 2 shows a side view of the latch module,

[0031] FIG. 3 shows a sectional view of the latch module along the plane A-A indicated in FIG. 2.

[0032] FIGS. 4A and 4B show a sectional view of the latch module along the plane B-B indicated in FIG. 3, however with different positions of a blocking member.

[0033] FIGS. 5A and 5B show a sectional view of the latch module along the plane C-C indicated in FIGS. 4A and 4B, respectively.

[0034] FIG. 6 shows an exploded view of the latch module.

[0035] Generally, the drawings are not to scale. Like elements and components are referred to by like labels and numerals. For the simplicity of illustrations, not all elements and components depicted and labeled in one drawing are necessarily labels in another drawing even if these elements and components appear in such other drawing.

[0036] While various modifications and alternative forms, of implementation of the idea of the invention are within the scope of the invention, specific embodiments thereof are shown by way of example in the drawings and are described below in detail. It should be understood, however, that the drawings and related detailed description are not intended to limit the implementation of the idea of the invention to the particular form disclosed in this application, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.

DETAILED DESCRIPTION

[0037] The latch module (a deadlatch assembly) as shown in FIGS. 1, 2, 3, 4A, 4B, 5A, 5B, and 6 has a housing 10 with a door-jamb-facing surface 11 and a door-leaf- facing surface 12. The door-jamb-facing surface 11 defines a first end of the housing 10 (a so called distal end of the housing. At the opposite side of the distal end of the housing 10 is a door-leaf -facing surface 12, defining a second end or the so -called proximal end of the housing 10 (see, for example, FIGS. 1 and 2). As can be seen for example in FIG. 6, the housing 10 may include a sleeve portion 10A, a stem guide 16, a rear plate 17 and a front plate 18.

[0038] Generally, the housing 10 movably supports a latch bolt 30 and guard bolt 50. A stem 20 (shown in FIG. 2) extends to the proximal side out of the housing 10 and is structured to be connected to a transmission configured to convert a pivotal movement of a door handle into a translation, thereby pulling the stem 20 in the proximal direction 3 (see FIGS. 1 and 2). As will be explained in more detail below, a movement of the stem 20 (from its closed position as shown in FIGS. 2, 3, 4A, 4B) in the proximal direction (that is indicated by an arrow 3) first releases the blocking mechanism and subsequently entrains the latch bolt 30 into a retracted position. The latch bolt 30 entrains the guard bolt 50 until both reach their respective retracted positions. Now, the door leaf can be swung and thus opened open. In the case when the door has been opened and the door handle (or any other kind of actuation means) is released, the latch bolt 30 and the guard bolt 50 are advanced by elastic biasing means 19 (shown, for example, in FIG. 19, and referred to as aspring 19, for short) into their respective extended position. This extended position of the latch bolt 30 is illustrated in

[0039] FIGS. 1, 2, 3, 4A, 4B, 5A, and 5B. FIGS. 1 to 3, 4B and 5B show the latch module with the guard bolt 50 in its extended position as well. FIG. 4A and FIG. 5A show a blocking member or mechanism 70 in a blocking position, which is taken or assumed by the blocking member 70 if the guard bolt 50 is retracted while the latch bolt 30 is extended. As will be apparent from the discussion below, in the extended position the guard bolt 50 maintains a blocking mechanism 70 released and the latch bolt 30 can retract if the door is slammed into its closed position.

[0040] In the case when the door is closed, the corresponding striking plate or any other portion of the door jamb maintains the guard bolt 50 in its retracted position. The blocking member 70 can thus engage and block a retraction of the latch bolt, until the blocking member 70 is released by pulling the stem in the proximal direction 3.

[0041] As can be seen in FIG. 3, the housing 10 may have or enclose at least one bearing rod (shown here as bearing rods 13, 15) essentially parallel to the longitudinal axis 2. The bearing rods 13, 15 of the example of FIG. 3 may each have a cylindrical peripheral surface. For the commonly-recognized and accepted definition of a cylinder and a cylindrical surface see Bronstein, Semendyayev, Musiol & Muehlig Handbook of Mathematics, Springer Berlin Heidelberg, 2007, 5th ed.; Chapter 3.3.4. Cylinders may have circular and non-circular direction curves and thus corresponding cross sections; for the purposes of this disclosure the surfaces with a circular cylindrical volume are preferred.

[0042] At least a portion of such peripheral surface may be a plain bearing surface configured to enable a translation of the latch bolt 30 and the guard bolt 50, respectively, essentially parallel to the longitudinal axis 2 along the respective bearing rod of rods 13, 15. Accordingly, the latch bolt 30 and the guard bolt 50 may each have at least one recess (shown in FIG. 3 as respective recesses 33 and 55) having an inner surface, providing a complementary plain bearing surface. Further, an inner surface 14 of the housing 10 may provide a further plain bearing surface movably supporting the latch bolt 30 and the guard bolt 50. The latch bolt 30 and the guard bolt 50 may slide along the inner surface 14 of the housing 10 with at least a portion of their respective peripheral surfaces.

[0043] The guard bolt 50 may have an abutment 53 that faces the latch bolt 30. The abutment 53 of the guard bolt 50 may be integrally formed, e.g., by a protrusion of the guard bolt 50. Alternatively, as depicted, the abutment 53 of the guard bolt 50 may be provided by an abutment plate 54. Like in the depicted example, the abutment plate 54 may extend orthogonally to the longitudinal axis 2 into the path of the latch bolt 30. Thus, when retracting the latch bolt 30, the abutment 35 of the latch bolt may contact a block 35 (that faces the guard bolt 50) of the latch bolt 30, thereby entraining the guard bolt 50 towards the retracted position. In other words, if the latch bolt 30 is in its retracted position, the guard bolt 50 is a corresponding retracted position as well. The guard bolt 50, in contrast may be shifted (and/or maintained) into (in) its retracted position while the latch bolt 30 remains extended or is in the process of being extended.

[0044] As was already mentioned initially, the stem 20 is preferably movably supported relative to the housing 10. A rear portion 22 of the stem 20 may be configured to be coupled to a transmission. As can be seen in FIGS. 4A and 4B, the stem 20 may be movably supported relative to the latch bolt 30, as well. For example, as depicted, a front-end portion 21 (also referred to as distal portion 21) of the stem 20 may engage, e.g. via a through hole in an optional rear plate 34 of the latch bolt 30 into a(nother) recess 36 of the latch bolt 30. For simplicity, such through hole may be considered as a part of another recess 36. At least a portion of the surface delimiting the trough hole may be a plain bearing surface enabling a translation of the stem 20 relative to the latch bolt 30 essentially parallel to the longitudinal axis 2. This movement of the stem 20 relative to the latch bolt 30 may be limited in the proximal direction 3. For example, as can be seen in FIGS. 4A and 4B, the stem 20 may have a block 23 configured to entrain an abutment 32 of the latch bolt 30. The position of the stem 20, when the block 23 contacts the abutment 32, is referred to as a first intermediate position. The act of retracting the stem 20 from the first intermediate position towards its open position retracts the latch bolt 30.

[0045] An embodiment 1 of the latch module may further include a blocking member 70. The blocking member 70 can be seen in FIGS. 4A, 4B, 5A and FIG. 5B:

[0046] The blocking member 70 may include a first leg 80 and second leg 90. The first leg 80 (also referred to as the front leg 80) has a front-end portion 81 and a rear-end portion 82. Similarly, the second leg 90 (also referred to as the rear leg 90) has a front-end portion 91 and a rear-end portion 92. The front-end portion 81 of the first leg 80 may be pivotably hinged to the latch bolt 30 by a front hinge. The front hinge has a front hinge axis 71. The first leg 80 may thus pivot relative to the front hinge axis 71.

[0047] The rear-end portion 82 of the first leg 80 may be connected by a middle hinge (indicated by a middle hinge axis 73) to the front-end portion 91 of the second leg 90, thereby enabling a pivotal movement of the first and second legs 80, 90 relative to each other around the middle hinge axis 73. The rear-end portion 92 of the second leg 90 may be connected by a rear hinge, as indicated by a rear hinge axis 72, relative to the housing 10 or any other structure being firmly attached to a door leaf (or doorjamb) when the latch module 1 is mounted to the door leaf (or door jamb).

[0048] As can be seen, the three axes 71, 72 and 73 are preferably at least essentially parallel to each other and therefore can define a plane 74 that includes the front and rear hinge axes 71 and 72 (see FIG. 5). The front and rear legs 80, 90 may may be inclined with respect to one another at an angle α. This optional angle α can take different values, depending on the relative position of the first and second legs 80, 90 relative to each other, however it has a minimum value as shown in FIG. 4A and FIG. 5A. This minimum value may be defined by a block 79 being attached to the housing 10 or being integrally formed by the housing 10. In the depicted example, the block 79 is provided by the stem guide 16 of the housing 10. It is noted that the block 79 may be provided by any other part, provided the block 79 limits the movement of the second leg 90. Alternatively or in addition, the block 79 may be positioned to block the movement of the first leg 80, e.g. by abutting the first leg 80 in the case when the blocking member is in its blocking position. Regardless of the position of the block 79, it preferably delimits a movement of the hinged legs 80, 90 in a direction perpendicular to the plane 74 to thereby define a minimum angle a.sub.minIn FIGS. 4A and 5A the positions of the first and second legs 80, 90 correspond to such minimum angle α.sub.min, i.e. α=α.sub.min. When a force is applied in the proximal direction 3 to the extended portion of the latch bolt 30, a movement of the latch bolt 30 is blocked by the blocking member 70, as the first and second legs 80, 90 are blocked from pivoting in a direction which would reduce the angle α below α.sub.min. It is recalled that in FIG. 4A and 5A the guard bolt 50 is in its retracted position (in FIG. 4A the guard bolt is hidden from view by the stem 20, and in FIG. 5A the guard bolt 50 is below the section plane C-C). However, when pulling the stem 20 towards its open position (i.e. in the proximal direction 3) a releasing member 29 of the stem may contact an abutment 99 of the blocking member 70. The position of the stem 20, when this contacting takes place is referred to as a second intermediate position. The act of shifting the stem 20 from the second intermediate position to the first intermediate position, shifts the middle axis 73 of the blocking member 70 on the opposite side of the plane 74 (i.e. α>180°. The result is similar to the situation depicted in FIGS. 4B and 5B, however in these two Figures the blocking member 70 is maintained in its released position by the guard bolt 50. In FIGS. 4B and 5B the stem is in its closed position.

[0049] By shifting the stem 20 from the second intermediate position into the first intermediate position, the blocking member 70 is released. At the first intermediate position, the stem's block 23 contacts the latch module's abutment 32 and thus entrains the latch bolt 30 in the proximal direction, thereby enabling a user to open the door by pulling (e.g., via an optional transmission) the proximal end 22 of the stem 20. After the door leaf has been swung to open, the pulling force may be released. The latch bolt 30 and the guide bolt 50 are shifted by the elastic members 19 (springs, for example) into their corresponding extended positions. The blocking member 70 is as well biased by an elastic biasing member 19 (spring 19, for short) towards the blocking position of the blocking member 70, however the extended guard bolt 50 prevents the blocking member 70 from entering the blocking position. This situation is depicted in FIG. 4B and FIG. 5B. For example, a protrusion 85 of the first leg 80 may interfere with a rear portion of the extended guard bolt 50. There are multiple possibilities, a first of which has already been indicated above, namely the protrusion 85 may abut the guard bolt 50, when the guard bolt 50 is in its extended position. In this example, the protrusion 85 may abut the abutment plate 54 when the guard bolt 50 is extended. Retracting the guard bolt 50 shifts the abutment plate 54 into another position and enables the blocking member 70 to enter its blocking position. Alternatively or in addition, the guard bolt 50, when being retracted, may shift the blocking member 70 into the released position of the blocking member 70. In both cases, the latch bolt 30 (entraining the guard bolt 50), may become temporarily retracted if the door is slammed into the door jamb and the door closes: The oblique surface of the latch bolt 30 hitting the door jamb's striking plate provides a pushing force in the proximal direction 3. Because the guard bolt 50 is extended, the blocking mechanism 40 is released (or becomes released when the guard bolt 50 is entrained by the block 35, of the latch bolt, contacting the guard bolt's abutment 53). In other words, the latch bolt 50 may retract until the door leaf reaches its closed position and the spring 19 extends the latch bolt 30 to engage into the striking plate. The striking plate at the same time inhibits the guard bolt 50 from extending and, as a consequence, the blocking member's biasing spring 19 shifts the blocking member into its blocking position. Now, the latch bolt 30 is blocked in its extended position and retracting the latch bolt 30 by a credit card is reliably prevented.

[0050] It will be appreciated to those skilled in the art having the benefit of this disclosure that this invention is believed to provide a latch module. Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the following claims.

[0051] For the purposes of this disclosure and the appended claims, the use of the terms “substantially”, “approximately”, “about”, “essentially” and similar terms in reference to a descriptor of a value, element, property or characteristic at hand is intended to emphasize that the value, element, property, or characteristic referred to, while not necessarily being exactly as stated, would nevertheless be considered, for practical purposes, as stated by a person of skill in the art. These terms, as applied to a specified characteristic or quality descriptor means “mostly”, “mainly”, “considerably”, “by and large”, “to great or significant extent”, “largely but not necessarily wholly the same” such as to reasonably denote language of approximation and describe the specified characteristic or descriptor so that its scope would be understood by a person of ordinary skill in the art. In one specific case, the terms “approximately”, “substantially”, “essentially” and “about”, when used in reference to a numerical value, may represent a range of plus or minus 20% with respect to the specified value, more preferably plus or minus 10%, even more preferably plus or minus 5%, most preferably plus or minus 2% with respect to the specified value. As a non-limiting example, two values being “substantially equal” to one another may imply that the difference between the two values may be within the range of +/−20% of the value itself, preferably within the +/−10% range of the value itself, more preferably within the range of +/−5% of the value itself, and even more preferably within the range of +/−2% or less of the value itself.

LIST OF REFERENCE NUMERALS

[0052] 1 latch module/deadlatch assembly

[0053] 2 longitudinal axis

[0054] 3 proximal direction

[0055] 4 distal direction

[0056] 10 housing

[0057] 11 first side

[0058] 12 second side

[0059] 13 bearing rod

[0060] 14 inner surface (plain bearing surface)

[0061] 15 bearing rod

[0062] 16 stem guide

[0063] 17 rear plate

[0064] 18 front plate

[0065] 19 elastic biasing means (e.g. spring)

[0066] 20 stem

[0067] 21 front-end portion (distal portion) of stem 20

[0068] 22 rear-end portion (proximal portion) of stem 20

[0069] 23 block

[0070] 27 releasing member

[0071] 30 latch bolt

[0072] 32 abutment

[0073] 33 recess

[0074] 34 rear plate

[0075] 35 guard bolt facing block

[0076] 36 recess

[0077] 50 guard bolt/deadlatch button

[0078] 53 latch bolt facing abutment

[0079] 54 abutment plate

[0080] 55 recess

[0081] 70 blocking mechanism

[0082] 71 front hinge axis

[0083] 72 rear hinge axis

[0084] 73 middle hinge axis

[0085] 74 plane

[0086] 80 first leg

[0087] 81 front-end portion of the first leg

[0088] 82 rear-end portion of the first leg

[0089] 90 second leg

[0090] 91 front-end portion of the second leg

[0091] 92 rear-end portion of the second leg