Technical Field

[0001 ] This invention generally relates to an electric strike assembly for installation in a door jamb. The electric strike assembly has been developed for installation in an extruded metal doorjamb, however the electric strike assembly may be suitable for installation in other forms of door jamb.

Background of Invention

[0002] An electric strike assembly generally includes a housing with mounting flanges that are mounted to the door jamb, having a keeper that interacts with a bolt of a latchbolt assembly mounted to the door panel. The keeper is pivotally mounted to the housing so that the keeper pivots when the door panel is moved from the closed position to the open position. A lock mechanism is provided within the housing which interacts with the keeper so that the keeper can only pivot when authorised credentials are presented.

[0003] The lock mechanism will utilises some form of powered actuator, such as a motor or solenoid to adjust the condition of the lock mechanism. Accordingly the electric strike assembly will generally be wired to an external power source. The lock mechanism will also utilise an electronic controller, which is wired to a card reader or the like mounted near the doorjamb, to process access credentials. It is therefore necessary that power and communication cabling be run to the electric strike assembly, and having a hollow doorjamb facilitates this.

[0004] Hollow door jambs are often formed from extruded metal having a constant cross section. The process of extruding the metal can involve forming relatively thin walled members being supported by longitudinally extending ribs. The ribs provide rigidity to the thin wall member. The ribs are also used to accommodate screw fasteners longitudinally therein. A top plate of a door frame may for example be fastened to the door jamb by screwing into the ribs. [0005] When the electric strike assembly is installed, the installer must make a series of cuts at various angles on two adjacent sides of the door jamb. Also the rib is often in a location that inhibits the mounting flanges being attached to locate a side of the housing with a side of the door jamb. Instead the installer must grind down the rib, often using a hand file, so that the mounting flanges on the housing can be fitted flush with the inner front surface of the door jamb.

[0006] A reference herein to a patent document or other matter which is given as prior art is not to be taken as an admission that that document or matter was known or that the information it contains was part of the common general knowledge as at the priority date of any of the claims.

Summary of Invention

[0007] According to this invention there is provided an electric strike assembly for installation in a door jamb including a housing, a keeper that is pivotable relative to the housing, an upper mount at a upper end of the housing and a lower mount at a lower end of the housing which is longitudinally spaced from the upper end of the housing, each of the upper mount and the lower mount having a first leg and a second leg which is laterally spaced from the first leg, each of the first leg and the second leg having a free end for engaging the door jamb when in use, each of the upper mount and the lower mount having a fastening zone extending between the first leg and the second leg being adapted for fastening to the doorjamb when in use, each fastening zone being spaced laterally from each free end of the respective said first leg and said second leg.

[0008] The electric strike preferably includes a faceplate attached to a front of the housing, and a side plate attached to a side of the housing. It is preferred the side plate is attached to the side of the housing by at least one pin, wherein access to the pin is hindered once the faceplate is attached. It is further preferred that the faceplate is attached by at least one threaded fastener. It is still further preferred that the upper mount and the lower mount are each fastened in use to the housing with a threaded fastener, whereby access to each said threaded fastener attaching the upper mount and the lower mount is hindered once the side plate is attached. [0009] In a preferred arrangement the side plate includes a cover portion that extends substantially parallel to the side of the housing, and also a lip portion that extends substantially perpendicular to the cover portion. It is preferred that the side plate and the face plate are each formed from stainless steel and each shaped so that in use no more than two vertical and two horizontal cuts in the door jamb are required.

[0010] It is preferred that each fastening zone includes an aperture to receive a threaded fastener. The preferred arrangement has each fastening zone extends perpendicularly to its respective first leg and second leg so as to form a U-shape. The U-shape is so configured to in use straddle a stiffening rib formed on an inner surface of the door jamb.

[001 1 ] According to another aspect of this invention there is provided an electric strike assembly for installation in a door jamb including a housing, a keeper that is pivotable relative to the housing, a faceplate attached to a front of the housing, and a side plate attached to a side of the housing, wherein the side plate is attached to the side of the housing by at least one pin, wherein access to the pin is hindered once the faceplate is attached. The faceplate is preferably attached by at least one threaded fastener. The electric strike preferably includes an upper mount at a upper end of the housing and a lower mount at a lower end of the housing which is longitudinally spaced from the upper end of the housing wherein the upper mount and the lower mount are each fastened in use to the housing with a threaded fastener, whereby access to each said threaded fastener attaching the upper mount and the lower mount is hindered once the side plate is attached. The upper mount and the lower mount may have a first leg and a second leg which is laterally spaced from the first leg, each of the first leg and the second leg having a free end for engaging the door jamb when in use, each of the upper mount and the lower mount having a fastening zone extending between the first leg and the second leg each fastening zone includes an aperture to receive a threaded fastener for fastening to the door jamb when in use, each fastening zone being spaced laterally from each free end of the respective said first leg and said second leg.

[0012] The side plate preferably includes a cover portion that extends

substantially parallel to the side of the housing, and a lip portion that extends substantially perpendicular to the cover portion. The side plate and the face plate are each preferably formed from stainless steel and each shaped so that in use no more than two vertical and two horizontal cuts in the doorjamb are required.

[0013] The housing of the electric strike assembly preferably a longitudinal dimension of no more than 86mm, a depth of no more than 25mm and or a width of no more than 36mm.

[0014] Reference throughout this specification to 'one embodiment' or 'an embodiment' means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases 'in one embodiment' or 'in an embodiment' in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristic described herein may be combined in any suitable manner in one or more combinations.

[0015] In order that the invention may be more readily understood and put into practice, one or more preferred embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings.

Brief Description of Drawings

[0016] Figure 1 is an isometric view of an electric strike according to a preferred embodiment of the invention when installed in a door jamb.

[0017] Figure 2 is an exploded isometric view of the electric strike and door jamb from Figure 1.

[0018] Figure 3 is an isometric view of the electric strike from Figure 1 with a rear cover removed to reveal the lock mechanism in a release condition, and the keeper in a closed position.

[0019] Figure 4 is an isometric view of the electric strike from Figure 3 with the keeper moved to an open position. [0020] Figure 5 is an isometric view of the electric strike from Figure 3 with the lock mechanism in a lock condition.

[0021 ] Figure 6 is an isometric view of a rear view of the electric strike installed in the door jamb from Figure 1.

[0022] Figure 7 is an alternate isometric view of the electric strike from Figure 2.

[0023] Figure 8 is an isometric view of the electric strike from Figure 1 installed in a wider door jamb.

[0024] Figure 9 is an exploded isometric view of the electric strike from Figure 8.

Detailed Description of Drawings

[0025] Referring first to Figure 1 which illustrates a preferred embodiment of an electric strike assembly 1 according to the invention installed in a door jamb 2. The door jamb 2 illustrated is merely an example of an extruded profile normally formed from metal that might be found in a commercial/office building where electric strikes are a preferred form of security device. The invention is not limited to use with a door jamb 2 having the specific cross section as shown. However it should be noted that the form of doorjamb illustrated includes ribbing 3 (see also Figure 6) on an inner surface thereof, and such ribbing 3 is often used to provide rigidity to the extruded profile.

[0026] Figure 1 illustrates a face plate 4 which is positioned substantially flush with a front wall 5 of the doorjamb 2, and a side plate 6 slightly protruding from a side wall 7 of the door jamb 2. Figure 1 also illustrates a keeper 8 which in use interacts with a bolt (not shown) of a latch bolt assembly (not shown) mounted to a door (not shown). The latch bolt assembly may take any suitable form and the person skilled in the art will appreciate that there are a range of latch bolt assemblies suitable for use with an electric strike. The electric strike assembly 1 includes a recess 9 formed between the keeper 8 and the housing 10 of the electric strike assembly 1 which is shaped to accommodate the bolt of the latch bolt assembly therein. The keeper 8 is pivotable relative to the housing 10 (see Fig. 2) in order to allow the door to move from a closed position to an open position in a manner that ought to be understood by those persons skilled in the art. The pivoting of the keeper 8 relative to the housing

10 will be described in greater detail by a reference to latter illustrations.

[0027] Referring now to Figure 2 which illustrates the electric strike assembly 1 in a partially exploded form separated from the doorjamb 2. Figure 2 illustrates the door jamb 2 having a cutout 1 1 created by two vertical cuts and two horizontal cuts. The installer must also drill an upper aperture 12 and a lower aperture 13 adjacent the cutout 11 in the door jamb 2 for attaching the electric strike assembly 1. The cutout

1 1 and the two drill apertures 12, 13 are the only modifications that the installer needs to make to the door jamb 2 when installing the electric strike assembly 1 which simplifies the installation process.

[0028] Figure 2 also illustrates an upper mount 14 and a lower mount 15 each of which are formed separately from the housing 10. Each of the upper mount 14 and lower mount 15 includes a first leg 16, 17 and a second leg 18, 19. It can be appreciated from Figures 6 or 7 that each first leg 16, 17 extends substantially parallel to the second leg 18, 19 with a base portion 20, 21 between each first leg 16, 17 and the second leg 18, 19 which for the purposes of this specification is referred to as a fastening zone 20, 21. In the preferred embodiment illustrated each fastening zone 20, 21 includes an aperture 22, 23 therein the facilitate attachment of the upper mount 14 and lower mount 15 to the door jamb 2 by way of a threaded fastener 24, 25.

Flowever, alternatively the upper mount 14 and lower mount 15 may be attached to the door jamb 2 by way of a self-tapping screw. Figure 2 also illustrates each second leg 18, 19 of the upper mount 14 and lower mount 15 being formed with an aperture 26, 27 therein to accommodate a threaded fastener 28, 29 for location in a threaded bore 30, 31 at longitudinally opposed ends of the housing 10.

[0029] Once the upper mount 14 and upper mount 15 have been fastened to the housing 10 the side plate 6 can be brought into engage with the side of the housing 10. The side plate 6 is formed with a pair of projections on an inner surface thereof (see Figure 7), for location in recesses 32, 33 formed in the side of the housing 10. A bore (not shown) is formed in each projection 30, 31 for accommodating a pin 34, 35 which is inserted in pin openings 36, 37 formed at the front of the housing 10 to locate in blind bores (not shown) formed in the side of the housing 10. Once the side plate 6 is attached to the housing 10 in this way access to the threaded fasteners 28, 29 attaching the upper mount 14 and the lower mount 15 to the housing 10 is hindered.

[0030] Figure 2 also illustrates the face plate 4 for location over front wall 5 of the housing 10. The face plate 4 is attached to the housing 10 by way of a pair of threaded fasteners 38, 39 which extend through apertures forming the face plate 4 and locate within threaded bores formed in the front wall 5 of the housing 10.

[0031 ] Each of the first leg 16, 17 and the second leg 18, 19 has a free end 44,

45, 46, 47 which is spaced from its respective the base portion. The free ends 44, 45,

46, 47 are positionable adjacent a rear surface of the front wall 5 of the door jamb 2 (see also Figure 6). It ought to be appreciated from Figure 2 that the free end 44, 45, 46, 47 of each of the first leg 16, 17 and the second leg 18, 19 is positioned relative to the housing 10 so that there is a partial overlap between the face plate 4.

[0032] The electric strike assembly 1 according to the invention includes a keeper 8 which is pivotable relative to the housing 10. Figures 3 and 4 illustrate how the keeper 8 pivots relative to the housing 10, and is biased towards the closed position as illustrated in Figure 1 under the action of a torsion spring 48. Figure 3 illustrates the keeper 8 having a pair of arms 49, 50, and it can be appreciated by comparing Figures 3 and 4 that these arms 49, 50 move relative to mounts 51 , 52 formed on the housing 10. Each mount 51 , 52 retains a detent pin 53, 54 therein which moves relative to the mount 51 , 52 as the keeper 8 pivots relative to the housing 10.

Movement of each detent pin 53, 54 causes an articulated member 55 to collapse in on itself, however it ought to be appreciated that the articulated member 55 is biased towards the extended position illustrated in Figure 3 under the influence of a further torsion spring (not shown). The detent pins 53, 54 and articulated member 55 formed part of a lock mechanism which also includes a powered actuator 56 illustrated in the form of an electric motor 56. The electric motor 56 when energised rotates an output shaft 57 through a gearbox 58 so as to move a shuttle 59 relative to the housing 10. This movement of the shuttle 59 causes an abutment 60 to pivot from a release position as illustrated in Figure 4 to a lock position as illustrated in Figure 5. It ought to be appreciated that once the abutment 60 adopts the position as illustrated in Figure 5, the articulated member 55 is incapable of collapsing and thereby the keeper 8 is retained in the closed position. This lock mechanism as hereinbefore described as merely preferred, and the electric strike assembly 1 of the invention may utilise other forms of lock mechanism.

[0033] It ought to be appreciated from Figure 1 that the keeper 8 must be positioned relative to the doorjamb 2 to enable it to pivot freely from the closed position. Figure 8 illustrates an example where the electric strike assembly 1 is set back from the side edge of the door jamb 2 in a manner that may be preferred. In such an arrangement the side panel 6 as previously described and illustrated may be replaced with a side panel 106 having a cover portion 107 which extends substantially parallel to the side of the housing 10, and a lip portion 108 that extends substantially perpendicular to the cover portion 107. Figure 9 illustrates the alternate side panel 106 whereby an upper and lower aperture 109, 110 is formed therein for connecting one panel 106 together to a further lip member 1 11 by way of an upper and lower pin 1 12, 1 13 in a friction fit. This combined form of side plate 6 is illustrated in Figure 8 and recesses the electric strike assembly 1 further away from the side wall 7 of the door jamb 2.

[0034] The electric strike housing 10 as hereinbefore described is relatively compact and has a longitudinal dimension of no more than 86mm. It is further preferred that the housing have a width dimension of no more than 36mm and a depth dimension of no more than 25mm. This allows for a relatively small opening to be formed in the door jamb 2 which is of a size not too dissimilar to existing standard, non-electric strikes.

[0035] It ought to be appreciated from the foregoing that the electric strike assembly 1 as hereinbefore described is relatively compact and therefore easy to fit to a door jamb 2. Utilisation of an upper mount 14 and a lower mount 15 which are preferably detachable from the electric strike housing 10, each mount being configured to straddle any stiffening ribs 3, again simplifies the installation process.

[0036] The foregoing embodiments are illustrative only of the principles of the invention, and various modifications and changes will readily occur to those skilled in the art. The invention is capable of being practiced and carried out in various ways and in other embodiments. It is also to be understood that the terminology employed herein is for the purpose of description and should not be regarded as limiting.

[0037] Various alterations and/or additions may be introduced into the electric strike assembly as hereinbefore described without departing from the spirit or ambit of the invention.