AU2019200210B2

AU2019200210B2 - Flush bolt

Info

Publication number: AU2019200210B2
Application number: AU2019200210A
Authority: AU
Inventors: Tim Everett; Jon Seddon
Original assignee: KDB Intellectual Pty Ltd
Current assignee: KDB Intellectual Pty Ltd
Priority date: 2018-01-11
Filing date: 2019-01-11
Publication date: 2023-09-07
Anticipated expiration: 2039-01-11
Also published as: AU2019200210A1; NZ749918A

Abstract

An adjustable flush bolt mechanism for mounting on a free edge of a door for providing latch bolt engagement between the door and a door frame, ceiling or floor, when the mechanism is in an engaged condition, the mechanism including: i) a housing being mountable within the free edge of the door; ii) a latch bolt comprising a proximal end and a distal end; iii) a carrier member which is adapted to engage with the proximal end of the latch bolt; iv) a crank being pivotally connected to the housing and comprising a first arm and a second arm; v) a link member which is connectable to a proximal end of the carrier member, and a crank end which is connectable to the first arm of the crank; and vi) an activator tongue comprising a strike end and a cam end and being movable within the housing, wherein, pushing of the activator tongue substantially into the housing causes the mechanism to adopt an engaged condition, wherein the cam end of the activator tongue acts upon the second arm of the crank, whereby the crank rotates about its pivot and causes the first arm to move, whereby the link member connectable thereto urges against the carrier member and causes the latch bolt to extend from the door. 1/3 Figure 1 144 164 110160 140 162 150 173 130 136 122 138 126 176 132 112 128 172 120 170 175 124 174 Figure 2 164 144 142 154 152 130

Description

1/3

Figure 1 144 164 110160 140 162 150 173 130 136 122 138 126 176 132 112 128 172 120 170 175 124 174

Figure 2

164 144 142 154 152

FLUSH BOLT FIELD OF THE INVENTION

[0001] The present invention relates to a flush bolt mechanism commonly used in connection with a double door as the latch mechanism mounted on the door that normally remains closed. The present invention further relates to an adjustable flush bolt mechanism.

BACKGROUND

[0002] The present invention relates to a flush bolt mechanism that is typically used for bolting the inactive door in a pair of swinging double doors. More particularly the present invention relates to bolts mounted flush with the free edge of the inactive doors for bolting the inactive door to the door frame. In typical application, one or two flush bolts may be used in an installation. Typically, one bolt is used to bolt the top of the inactive door to the ceiling or top of the door frame and one bolt is used to bolt the bottom of the inactive door to the floor or bottom of the door frame. Flush bolts may be manual, semi-automatic, or automatic. A manual flush bolt must be operated by hand in order to open or close the door. A hand-operated switch or lever controls the position of the bolt between an engaged position and a disengaged position. In a semi-automatic flush bolt, the door may close and latch itself automatically, but a hand operated control lever or switch must be manually activated in order to release the bolt to open the door. In an automatic flush bolt, a trigger or sensor on the free edge of the inactive door senses whether or not the active door is closed, i.e. is adjacent to it. When the active door is closed, the trigger causes the automatic flush bolt to change to the engaged position, when the active door is again open, the trigger releases causing the automatic flush bolt to return to the disengaged position.

[0003] It is an aspect of the present invention, to provide an improved flush bolt mechanism that ameliorates one or more shortcomings of previous flush bolt mechanisms.

SUMMARY OF THE INVENTION

[0004] Although fit for their intended purposes, previous flush bolts of the prior art feature lack the ability to be adjusted to suit different door/ceiling/floor arrangements.

[0005] The present invention provides an adjustable flush bolt mechanism for mounting on a free edge of a door for providing latch bolt engagement between the door and a door frame, ceiling or floor, when the mechanism is in an engaged condition, the mechanism including: i) a housing being mountable within the free edge of the door; ii) a latch bolt comprising a proximal end and a distal end; iii) a carrier member which is adapted to engage with the proximal end of the latch bolt; iv) a crank being pivotally connected to the housing and comprising a first arm and a second arm; v) a link member which is connectable to a proximal end of the carrier member, and a crank end which is connectable to the first arm of the crank; and vi) an activator tongue comprising a strike end and a cam end and being movable within the housing, wherein, pushing of the activator tongue substantially into the housing causes the mechanism to adopt an engaged condition, wherein the cam end of the activator tongue acts upon the second arm of the crank, whereby the crank rotates about its pivot and causes the first arm to move, whereby the link member connectable thereto urges against the carrier member and causes the latch bolt to extend from the door.

[0006] Preferably, the carrier member comprises an opening in its distal end, the opening being adapted to receive the proximal end of the latch bolt. Preferably, the proximal end of the latch bolt comprises an external threaded portion and optionally, an elongate recess extending along a side of the latch bolt; and the distal end of the latch bolt comprises means by which rotation of the latch bolt may be effected.

[0007] Accordingly, in an exemplary embodiment, the present invention provides an adjustable flush bolt mechanism for mounting on a free edge of a door for providing latch bolt engagement between the door and a door frame, when the mechanism is in an engaged condition, the mechanism including: i) a housing being mountable within the free edge of the door; ii) a latch bolt comprising a proximal end and a distal end, wherein: the proximal end of the latch bolt comprises an external threaded portion and an elongate recess extending along a side of the latch bolt; and the distal end of the latch bolt comprises means by which the latch bolt may be rotated; iii) a carrier member comprising an opening in its distal end which is adapted to receive the threaded, proximal end of the latch bolt; iv) a crank being pivotally connected to the housing and comprising a first arm and a second arm, v) a link member having a carrier end which is pivotally connected to a proximal end of the carrier member, and a crank end which is pivotally connected to the first arm of a crank; and vi) an activator tongue comprising a strike end and a cam end and being movable within the housing, wherein, movement of the activator tongue into the housing causes the mechanism to adopt an engaged condition, wherein the cam end of the activator tongue bears against the second arm of the crank, whereby the crank rotates about its pivot and causes the first arm to rotate, whereby the link member connected thereto pushes against the carrier member and causes the latch bolt to extend from the door.

BRIEF DESCIPTION OF THE DRAWINGS

[0008] In order that the invention may be readily understood and put into practical effect, reference will now be made to embodiments of the present invention with reference to the accompanying drawings, wherein like reference numbers refer to identical elements. The drawings are provided by way of example only, wherein:

[0009] Figure 1 shows a side view of an embodiment of an adjustable flush bolt mechanism according to the present invention, in a disengaged condition.

[0010] Figure 2 shows a side view of an embodiment of an adjustable flush bolt mechanism according to the present invention, in an engaged condition.

[0011] Figure 3 shows (A) an end-on view and (B) a top view, of an embodiment of an adjustable flush bolt mechanism according to the present invention, in a disengaged condition.

[0012] Figure 4 shows a cut-away view of an embodiment of an adjustable flush bolt mechanism according to the present invention, in a disengaged condition.

[0013] Figure 5 shows a cut-away view of an embodiment of an adjustable flush bolt mechanism according to the present invention, in an engaged condition.

DESCRIPTION OF THE INVENTION

[0014] The materials, methods and examples are illustrative only and are not intended to be limiting. Other features and advantages of the invention will be apparent from the detailed description and from the claims.

[0015] Embodiments of the present invention relate to an adjustable flush bolt mechanism suitable for mounting on a free edge of a door and providing a latch bolt engagement between the door and a door frame, ceiling or floor, when the mechanism is in an engaged condition.

[0016] As used herein, the term "engaged condition" refers to an arrangement where, in use, the latch bolt extends from the door in order to engage a door frame, ceiling or floor, whereby the door is unable to be moved upon its hinges.

[0017] As used herein, the term "disengaged condition" refers to an arrangement where, in use, the latch bolt is substantially completely within the door, whereby the door is able to be moved upon its hinges.

[0018] As used herein, the term "free edge" refers to the latch side of a door, that is, not on the hinge side.

[0019] As used herein, the terms "distal" and proximall" refer to distance from the centre of the free edge of the door, where proximal is closer to the centre of the door and distal is closer to the top or bottom edges of the door.

[0020] As used herein, the indefinite articles "a" and "an" preceding an element or component of the invention are intended to be non-restrictive regarding the number of instances, i.e., occurrences of the element or component. Therefore "a" or "an" should be read to include one or at least one, and the singular word form of the element or component also includes the plural unless the number is obviously meant to be singular.

[0021] As used herein, the term "invention" or "present invention" is a non-limiting term and is not intended to refer to any single embodiment of the particular invention but encompasses all possible embodiments as described in the specification and the claims.

[0022] As used herein, the terms "comprise", "comprises", "comprised" or "comprising" are to be interpreted as specifying the presence of the stated features, integers, steps or components referred to, but not to preclude the presence or addition of one or more other feature, integer, step, component or group thereof.

[0023] The present invention provides an adjustable flush bolt mechanism for mounting on a free edge of a door, wherein the adjustable flush bolt mechanism allows the length of extension of the latch bolt to be readily adjustable. Typically, a latch bolt is used to prevent a door being able to swing on its hinges by being received in an opening in a door frame, floor or ceiling. Existing flush bolts extend from within the door leaf. However, the amount of extension from the door of such existing latch bolts is fixed and may not be appropriate for all installations of the latch bolt, because the latch bolt might be too long whereby the distal end of the latch bolt strikes the end of the opening and cannot be completely or properly deployed. Alternatively, the latch bolt might be too short and be unable to securely restrict movement of the door. Further, if there is movement of the door, or its surrounds, due to altering weather conditions, the ability of a latch bolt to secure a door may be compromised due to the latch bolt extending too far or not far enough.

[0024] The adjustability of the length of extension of the latch bolt is provided by the latch bolt being received within and adjustable with respect to a carrier, wherein the carrier is driven by the flush bolt mechanism as explained further herein.

[0025] In a preferred embodiment of the present invention the latch bolt includes an external threaded portion at its proximal end which is received with a correspondingly threaded opening within the carrier member. In some embodiments of the present invention, the threaded opening may comprise a short, threaded section at the distal end of the carrier member. In yet further embodiments, the opening in the carrier member may be threaded for at least a significant proportion of its length. Such arrangements allow the latch bolt to be received within the carrier while being threadedly engaged therewith to allow adjustability of the length of extension of the latch bolt.

[0026] In certain embodiments of the present invention, the length of extension of the latch bolt may be adjusted by rotating the latch bolt whereby it moves along the threaded portion of the carrier member to be screwed into or out of the carrier member. The latch bolt may include a slot in its distal end to allow adjustment using a screw driver. Additionally, or alternatively, the distal end of the latch bolt may include at least two flatted and substantially parallel sides to allow rotation using a spanner or similar gripping tool. In certain embodiments, the distal end of the latch bolt may be substantially hexagonal in cross section such that it is adapted to be adjusted using a socket, open-ended or ring spanner, or the like. When the flush bolt mechanism is installed in a door, it in expected that a slim open-ended spanner can be used to rotate the latch bolt as the gap between the door and floor, ceiling or door frame will be narrow, typically in the order of about 5mm.

[0027] In a further embodiment of the present invention, the position of the latch bolt within the carrier member may be releasably fixed by use of a fixing means such as a lock nut or a screw. In certain such embodiments a lock nut may be positioned on the threaded portion of the latch bolt and bears against the distal end of the carrier member whereby rotation (and alteration of length of extension of the latch bolt) may be prevented. If the length of extension of the latch bolt needs to be altered, a user may loosen the lock nut, rotate the latch bolt until it attains the desired length of extension, then tighten the lock nut against the distal end of the carrier member. In preferred embodiments, the fixing means is a screw, more preferably, a grub screw. In such embodiments the grub screw is housed within an opening in a side wall of the carrier member, and screwed into the carrier member whereby it bears against the latch bolt therein. Alteration of the length of extension of the latch bolt can be achieved by unscrewing the grub screw until it no longer bears against the latch bolt, rotating the latch bolt until it attains the desired length of extension, then tightening the grub screw against the latch bolt.

[0028] In yet further embodiments, the latch bolt may include one or more elongate recesses along at least a part of the threaded portion which is adapted and dimensioned to receive the grub screw. Such a recess may further assist in the prevention of rotation of the latch bolt within the carrier member.

[0029] Access to the fixing means may be provided by an opening in the housing positioned such that it is accessible when the flush bolt mechanism is in the disengaged condition. For example, a small hole in a side of the housing may align with the grub screw when the flush bolt mechanism is in the disengaged condition. Such a small hole is most conveniently positioned on the free edge of the door.

[0030] Preferably, the flush bolt mechanism is positioned in a mounting frame to allow installation within a door. In preferred embodiments, the mounting frame is substantially L-shaped, having a free-edge face and a horizontal face. In use, the free-edge face is mounted essentially flush with the free edge of the door and includes an opening through which a strike end of the activator tongue protrudes when the flush bolt mechanism is in the disengaged condition. The horizontal face includes an opening through which the latch bolt extends when the flush bolt mechanism is in the engaged condition. The free-edge face may include a further opening that aligns with the small hole in a side of the housing, that aligns with the grub screw when the flush bolt mechanism is in the disengaged condition, to allow access to the grub screw when the flush bolt mechanism is installed within a door.

[0031] A substantially L-shaped mounting frame may provide additional security improvements over previous flush bolt mechanisms. Being substantially L shaped means that fixing screws to attach the mounting frame to a door results in screws being positioned substantially parallel to each other. While, the visible screws on the free edge of the door are easily accessible and removable, the screws at the bottom or top of the door are not easily accessible. Accordingly, the door would need to be removed in order to access the bottom or bottom fixing screws.

[0032] The description provided hereinbelow relates to an automatic flush bolt mechanism; however, it is to be understood that the mechanism used to adjust the length of extension of the latch bolt may be applied equally to manual and semi-automatic flush bolt mechanisms.

[0033] The illustrated, exemplary embodiment of the present invention will now be described. It is to be understood that the illustrated embodiment is not to be considered as restricting the scope of the present invention, it is provided to demonstrate the present invention only. In such further embodiments, movement of the carrier member and latch bolt may be effected by use of a lever and other components connected thereto, rather than the activator tongue, crank and link described herein.

[0034] As illustrated in the accompanying drawings, the present invention provides an adjustable flush bolt mechanism 100 for providing latch bolt engagement between the door and a door frame, ceiling or floor, when the mechanism is in an engaged condition (Figures 2 and 5), the mechanism including: a housing 110 being mountable within the free edge of the door; a latch bolt 120 comprising a proximal end 122 and a distal end 124, wherein: the proximal end 122 of the latch bolt 120 comprises an external threaded portion 126 and an elongate recess 129 extending along a side of the latch bolt 120; and the distal end 124 of the latch bolt comprises means by which the latch bolt may be rotated; a carrier member 130 comprising an opening 132 in its distal end which is adapted to receive the threaded, proximal end 122 of the latch bolt 120; a crank 140 being pivotally connected to the housing 110 and comprising a first arm 142 and a second arm 144; a link 150 member having a carrier end 152 which is pivotally connected to a proximal end of the carrier member 130, and a crank end 154 which is pivotally connected to the first arm 142 of the crank 140; and an activator tongue 160 comprising a strike end 162 and a cam end 164 and being movable within the housing 110, wherein, pushing of the activator tongue 160 into the housing 110 causes the mechanism 100 to adopt an engaged condition, wherein the cam end 164 of the activator tongue 160 bears against the second arm 144 of the crank 140, whereby the crank 140 rotates about its pivot and causes the first arm 142 to rotate, whereby the link member 150 connected thereto pushes against the carrier member 130 and causes the latch bolt 120 to extend from the door. Preferably, the link member 150 and first arm 142 combine to provide greater vertical travel of the carrier member 130 than the horizontal travel of the activator tongue. In alternative embodiments, it is envisaged that the link member could be omitted, whereby the first arm acts directly upon the carrier member.

[0035] The adjustable flush bolt mechanism 100 further comprises a biasing means 128 whereby the mechanism adopts a disengaged condition when the activator tongue 160 is not pushed into the housing 110. The biasing means 128 is positioned between the carrier member 130 and a distal surface of the housing 110 whereby the biasing means 128 becomes compressed when the flush bolt mechanism 100 is in the engaged condition and urges the flush bolt mechanism 100 towards the disengaged condition when the activator tongue 160 is not pushed into the housing 110.

[0036] To prevent inadvertent adjustment of the length of extension of the latch bolt 120, the carrier member 130 comprises an opening 136 in a side of the carrier member 130 where a fixing means 138 is positioned therein for bearing against the latch bolt 120. The fixing means 138 prevents rotation of the latch bolt 120 relative to the carrier member 130.

[0037] The latch bolt 120 includes an elongate recess 129 along a side of the threaded portion 126 of the latch bolt 120. The elongate recess 129 is adapted to receive the fixing means 138 to substantially prevent rotation of the latch bolt 120 within the carrier member 130.

[0038] The housing 110 further comprises an opening 112 to allow access to the fixing means 138 when the flush bolt mechanism 100 is in the disengaged condition.

[0039] The distal end 124 of the latch bolt 120 comprises a slot and/or substantially flat and parallel sides, to facilitate rotation of the latch bolt 120 within the carrier member 130 by a user, to allow adjustment of the length of extension of the latch bolt 120. Such an arrangement allows adjustment of the length of extension of the latch bolt 120 while the flush bolt mechanism is installed in a door.

[0040] In the illustrated embodiment, the flush bolt mechanism 100 is positioned in a mounting frame 170 to allow installation within a door. The mounting frame 170 is substantially L-shaped, having a free-edge face 172 and a horizontal face 174. The free-edge face 172 includes an opening 173 through which a strike end 162 of the activator tongue 160 protrudes when the flush bolt mechanism 100 is in the disengaged condition. The horizontal face 174 includes an opening 175 through which the latch bolt 120 extends when the flush bolt mechanism 100 is in the engaged condition. The free-edge face 172 includes a further opening

176 that aligns with the small hole 112 in a side of the housing 110 that aligns with the fixing means 138 when the flush bolt mechanism 100 is in the disengaged condition, to allow access to the fixing means 138 when the flush bolt mechanism 100 is installed within a door.

[0041] Any prior art reference or statement provided in the specification is not to be taken as an admission that such art constitutes, or is to be understood as constituting, part of the common general knowledge.

[0042] Further patent applications may be filed in Australia or overseas on the basis of, or claiming priority from, the present application. The following example claims are provided by way of example only and are not intended to limit the scope of what may or may not be claimed in any future application. It should also be noted that features may be added to, and/or removed from, the claims in order to further define the claimed invention.

Claims

The Claims defining the invention are as follows:

1. An adjustable flush bolt mechanism for mounting on a free edge of a door for providing latch bolt engagement between the door and a door frame, ceiling or floor, when the mechanism is in an engaged condition, the mechanism including: i) a housing being mountable within the free edge of the door; ii) a latch bolt comprising a proximal end having an externally threaded portion and a distal end comprising means by which the latch bolt may be rotated; iii) a carrier member having a longitudinal axis and comprising a distal end having an opening which is adapted for threaded engagement with the proximal end of the latch bolt; iv) a crank being pivotally connected to the housing and comprising a first arm and a second arm; v) a link member which is connectable at a proximal end of the carrier member, and a crank end which is connectable to the first arm of the crank; and vi) an activator tongue comprising a strike end and a cam end and being movable within the housing, wherein, pushing of the activator tongue substantially into the housing causes the mechanism to adopt an engaged condition, wherein the cam end of the activator tongue acts upon the second arm of the crank, whereby the crank rotates about its pivot and causes the first arm to move, whereby the link member connectable thereto urges against the carrier member along the longitudinal axis and causes the latch bolt to extend from the door, and wherein rotation of the latch bolt adjusts the length of the latch bolt relative to the carrier member and the housing.

2. The adjustable flush bolt mechanism of claim 1, wherein: the proximal end of the latch bolt also comprises an elongate recess extending along a side of the latch bolt and the distal end of the latch bolt comprises means by which rotation of the latch bolt may be effected.

3. The adjustable flush bolt mechanism of claim 1 or claim 2, wherein the housing further comprises a biasing means whereby the mechanism adopts a disengaged condition when the activator tongue is not pushed into the housing.

4. The adjustable flush bolt mechanism of any one of claims 1 to 3, wherein the carrier member comprises a threaded opening in a side of the carrier member and a fixing means therein whereby rotation of the latch bolt relative to the carrier member may be restricted.

5. The adjustable flush bolt mechanism of claim 4, wherein the fixing means is adapted to engage the elongate recess extending along the side of the latch bolt.

6. The adjustable flush bolt mechanism of claim 4 or claim 5, wherein the housing further comprises an opening to allow access to the fixing means when the mechanism is in the disengaged condition.

7. The adjustable flush bolt mechanism of any one of claims 1 to 6 wherein the distal end of the latch bolt comprises a slot.

8. The adjustable flush bolt mechanism of any one of claims 1 to 7 wherein the distal end of the latch bolt comprises substantially flat and parallel sides.