GB2505997B - Universal lock strike system - Google Patents

Description

Universal Lock Strike System

The present invention relates to a universal lock strike system suitable for unplasticized polyvinyl chloride (uPVC) doors, and the like. uPVC door frames are formed from an extruded profile, and many different profiles have been used in recent years. uPVC doors are matched to the frame profile at the time of first fitting, but if the door is later replaced, a door profile to match the frame profile may be difficult if not impossible to find. Fitting new doors to existing frames consisting of uPVC hollow extruded section requires modification of frame elements to ensure the door will lock to the frame. Specifically, accurate positioning of the strike plate, to within ±l-2mm is required for satisfactory operation.

The strike plate has to be set level in order to be parallel with the lock itself (and ensure function thereof) in the door closed condition. This is known as pitch adjustment. The strike plate must also be set a certain distance from the frame seal, to ensure the door and the strike plate are aligned when the door is in the closed condition. This is known as lateral positioning.

The uPVC profiles for the sash (opening) side typically have a standard feature known as a “Eurogroove” which allows a door lock to be fitted. However there is little commonality as to the location of the Eurogroove relative to the frame, particularly because the frame profiles themselves tend to vary according to the manufacturer or series.

In practice fitting a new door to an old frame requires the use of packers. These are inserted between the strike plate and the door frame at intervals of typically 200mm, and are selected and positioned according to the judgement of the door fitter.

However, the wide variation in profiles of uPVC door frames and doors means that fitting is time intensive and relies upon the skill and conscientiousness of the fitter. A particular problem in the repair and maintenance market, is that a fitter may not know which profile has been used for the door frame until inspection, and given the large number of possible striker/frame combinations, it is impractical to carry inventory suitable for all. This may lead the fitter to modify a packer or strike plate in an ad-hoc manner, in order to achieve a fit. This is not desirable, and a better solution is required.

According to the first aspect of the invention there is provided a lock strike assembly for a door frame and comprising a strike plate, a packer and a grub screw, said strike plate comprising a C-section channel with a first flange and a second flange separated by a web; said strike plate having a threaded hole through the web, said packer having a plain hole for self-tapping by said grub screw, and said packer adapted to fit within said C-section channel in use between said web and a door frame such that said plain hole and said threaded hole are aligned, and said grub screw being engageable in the threaded hole; wherein pitch adjustment of the assembly relative to a door frame is achieved through pivoting of the assembly about an edge of the first flange of the strike plate by screwing the grub screw through the threaded hole and the plain hole, and wherein the assembly further comprises a protrusion, lateral positioning of the assembly relative to the door frame being achieved through abutment of said protrusion with the door frame.

By providing a means of adjusting the pitch and lateral positioning of the assembly, the lock strike assembly provides for universal fitting for substantially any uPVC door frame employing the Eurogroove frame system, thus accounting for both the varying profile of the frame and relative location of the door in its closed condition.

In a preferred embodiment, the plain hole in the packer of the lock strike assembly is elongate. This arrangement means that the same packer may be placed in several positions relative to the C-section channel, whilst ensuring that there is a continuous passage for a grub screw through the assembly. The plain hole may be off centre to permit the packer to be turned over or turned round to adjust position thereof.

The packer of the lock strike assembly may also have at least one clearance fit fixing hole. The strike plate of the lock strike assembly may have at least one fixing hole. To ensure the lock strike assembly is securely attached to the door frame, a screw-threaded fastener may be inserted through the aligned fixing holes, whilst avoiding the undesirable possibility of resistance between the packer and the strike plate.

In a preferred embodiment the protrusion of the lock strike assembly comprises a cam. The cam may be actuated through a cam actuation hole in the web of the strike plate. This arrangement allows lateral positioning of the assembly relative to the door frame to be tailored to each different door frame system. Furthermore, in use the fitter may position the lock strike assembly approximately, whilst manipulating the cam, which facilitates the process of setting the desired lateral position for the assembly.

The cam actuation hole and the threaded hole may located on a line extending perpendicularly from the flange of the strike plate . This arrangement facilitates installation, by having the adjustment features proximate to each other.

In a preferred embodiment the pivoting arc of the cam is restricted. In a preferred embodiment the pivoting of the cam is restricted to ±75° by the packer. The cam is provided to control lateral positioning of the assembly relative to the door frame. It is not necessary that the cam rotates, indeed it is undesirable. A visual indicator on the strike plate may indicate the degree to which the cam has been pivoted. This facilitates the setting of more than one cam to the same degree of pivot.

In a preferred embodiment the packer is U-shaped in form, having a central portion separating two arms. The cam is preferably located between the two arms of the packer.

The packer may have four clearance holes, two located on each arm of the packer, so as to increase the number of said fixing options.

In a preferred embodiment the packer may be supplied attached to the strike plate, by an adhesive. This arrangement allows the provision of the lock strike assembly as a partial-assembly, such that the number of loose parts supplied is reduced, mitigating the risk of lost/ misplaced components and reducing the steps of the installation procedure.

In another preferred embodiment the packer of the lock strike assembly features a pin, and the web of the strike plate features a pinhole, such that lateral positioning of the packer relative to the strike plate is achieved by engaging the pin in the pinhole.

The strike plate may have a plurality of pinholes, such that a range of lateral positions of the packer relative to the strike plate may be achieved. This arrangement simplifies the process for setting the lateral adjustment. Whilst there is no common position for the Eurogroove, the majority tend to be in one of three positions relative to the edge of the profile, (at a spacing of 9, 11, 13mm). Furthermore, if a number of packers are to be fitted along a length of strike plate (as is likely to be the case), then the fitter may simply select the same orientation of packer and pinhole in the strike plate to ensure alignment along the door edge.

The plurality of pinholes may be provided in a single punched detail. This arrangement allows for setting of the lateral adjustment with respect to the three common positions for the Eurogroove, but in a single manufacturing operation, reducing manufacturing time and complexity.

In a preferred embodiment the packer is rectangular in form, having two legs at two comers on the same side, extending towards a door frame in use.

The threaded hole in the strike plate may be located closer to the second flange than the first flange. The plain hole for self tapping may be circular and of a diameter that ensures thread cutting by the grub screw. In an alternative the plain hole may be oval or oblong to allow lateral re-positioning of the packer whilst ensuring the cutting of threads at the opposite sides thereof.

According to the second aspect of the present invention there is provided a method of installing the lock strike assembly of any preceding claim to a door frame, said method comprising the steps of (a) aligning the longitudinal axis of the strike plate with a vertical surface of the door frame; (b) setting the lateral positioning of the lock strike assembly relative to the door frame by positioning the protrusion relative to the strike plate; (c) abutting the protrusion against a groove of the door frame; (d) pivoting the lock strike assembly about the first flange by screwing the grub screw through the threaded hole of the strike plate and the plain hole of the packer such that the grub screw protrudes through the bottom of the lock strike assembly to abut the frame and set the desired pitch of the lock strike assembly relative to the frame; and (e) fixing the lock strike assembly to the door frame.

In a preferred embodiment the lateral position setting step (b) includes manipulating a cam using a key such that the second flange of the strike plate is the desired distance from a flange of the door frame, and wherein step (e) includes screwing one or more screws through the four clearance holes of the packer of the lock strike assembly. The cam may comprise a disc having an offset peg to engage an upstanding flange of a profiled section of the door frame.

In another preferred embodiment the lateral position setting step (b) includes selecting the appropriate packer orientation and pin to pinhole match such that when the legs are engaged in the groove the second flange of the strike plate is the desired distance from a flange of the door frame.

In a preferred embodiment the lock strike assembly comprises a strike plate with multiple packers and packer mounting locations, such that step (b) to (d) are repeated for each desired packer location.

Embodiments of the present invention will now be described by way of example and with reference to the accompanying drawings, in which:

Figure 1 is a partial perspective view of a section of an exemplar uPVC door frame.

Figure 2 is a side view of a lock strike assembly in a first embodiment;

Figure 3 is a plan view of the lock strike assembly of figure 2;

Figure 4 is a bottom view of the lock strike assembly of figure 2;

Figure 5 is a bottom view of the packer of the lock strike assembly of figure 2;

Figure 6A is a side view of the cam of the lock strike assembly of figure 2, figure 6B is a bottom view of the cam of the lock strike assembly of figure 2.

Figure 7 is a plan view of a lock strike assembly in a second embodiment;

Figure 8 is a cross sectional view of the lock strike assembly of figure 7, taken at line A-A;

Figure 9A is a side view of the packer of the lock strike assembly of figure 7, figure 9B is a bottom view of the packer of the lock strike assemble of figure 7;

Figure 10A is a plan view of a lock strike assembly in a third embodiment, figure 10B is a cross sectional view of the lock strike assembly of figure 10A, taken at line B-B.

An exemplar uPVC door frame 10 (see figure 1) comprises an extruded box section 2 with a flange 4 which provides mounting for a seal 6, and a groove 8, bounded by parallel sidewalls. The upper profile 12 between the flange 4 and groove 8 measures approximately 40mm and has a series of vertical surfaces, comprising upstanding ribs 14, each measuring no more than about 2mm in height, which do not have a standard position, but are located according to the profile selected by a particular manufacturer. A lock strike assembly 20 (see figures 2 to 4) comprises a strike plate 22, a packer 40, a grub screw 50 and an adjustable cam 60. The strike plate 22 comprises an elongate metallic C-section channel with first flange 28 and second flange 26 separated by a web 30.

The longitudinal axis 24 of the strike plate 22 is defined parallel to, and between, the first and second flanges 28, 26. In the web 30 is provided a threaded hole 32 and a cam actuation hole 34 on a transverse axis generally orthogonal to the longitudinal axis 24, and approximately equidistant on either side thereof. There are also four counter-sunk fixing holes 36, symmetrically positioned either side of the transverse and longitudinal axes.

The packer 40 (see figure 5) is a moulded plastic C-shape adapted to fit in the C-section channel of the strike plate 22, with the arms 42, 44 bridged by a central portion 46, where a hole 48 sized for self-tapping is centrally located. Two fixing holes 43 are located on each arm 42, 44. A first edge 47 comprising the two arms 42, 44 and the central portion 46 is located against an inside surface of the first flange 26 whilst a second edge 45 comprising the two arms 42, 44 only is located against an inside surface of the second flange 28.

The C-section strike plate 22 measures 7 mm in height and 31 mm in width, and is 2 mm thick. The recess formed within the C-section is therefore 5 mm in height and 27 mm in width. The packer 40 is 4 mm thick, such that when it is fixed into the C-section channel with adhesive it remains substantially flush with the ends of the first and second flanges 28, 26. In one embodiment the thickness of the packer 40 and adhesive in combination is such that the packer 40 does not protrude beyond the ends of the first and second flanges 28, 26 by more than 2 mm.

This positioning of the packer 40 in the C-section channel of the strike plate 22 ensures that the self-tapping hole 48 and threaded hole 32 are aligned such that a grub screw 50 may be inserted. Furthermore, the fixing holes 36 of the strike plate 22 and the fixing holes 43 of the packer 40 are aligned.

The threaded hole 32 in the strike plate 22 is approximately 4 mm in diameter, whilst the self-tapping hole 48 in the packer 40 is undersized, with diameter of approximately 3.8 mm. This ensures that the grub screw 50 is able to cut a thread into the packer 40.

The fixing holes 36, 43 in the strike plate 22, and packer 40, respectively, are approximately 4.3 mm in diameter, suitable for the use of 4.3 by 25 mm screws for securing the strike plate assembly 20 to the door frame. In another embodiment the fixing holes 36, 43 are 4.8 mm in diameter. A cam 60, (see figures 6A and 6B) comprises a cylinder with an offset peg 64 extending from a lower surface 62 and an offset open channel hex socket 66 adapted for engagement with a hex key.

Referring back to figure 2, the depth of the cam 60 is such that when located within the C-section channel of the strike plate 22, the cylinder does not protrude past the ends of the flanges 26, 28, however the offset peg 64 does. Thus, the offset peg 64 may be engaged within the groove 8 of the door frame 10, and bear against a sidewall thereof.

The cam 60 is eccentrically mounted in the gap between the central portion 46 and arms 42, 44 of the packer, to the cam actuation hole 34 (see figure 4). An inside edge 49 of the packer 40 at the root of the arms 42, 44 provides an abutment surface to prevent the cam 60 from rotating more than about ±75°.

The cam 60 is retained in the cam actuation hole 34 with a loose interference fit, such that it is free to pivot but is restricted against axial movement.

When installing or repairing a door frame, a strike plate 22 must be positioned on the upper profile 12 of the door frame 10 such that its longitudinal axis 24 is substantially parallel with the seal 6. For effective door operation, the lateral position of the strike plate 22, that is its proximity to the flange 4 or groove 8, and its pitch, that is the angle of the strike plate web 30 surface to the upper profile 12 of the door frame 10, must be controlled.

The method of installing the lock strike assembly 20 to door frame 10, comprises the steps of aligning the longitudinal axis 24 of the strike plate 22 with the seal 6, manipulating the cam 60 using a hex key such that when the offset peg 64 is engaged in the groove 8, the second flange 26 of the strike plate 22 is the desired distance from the flange 4 of the door frame 10. Then the lock strike assembly 20 is pivoted about the first flange 28 by screwing the grub screw 50 through the threaded hole 32 of the strike plate 22 and the self-tapping hole 48 of the packer 40 such that the grub screw 50 protrudes through the bottom of the lock strike assembly 20. This ensures that desired pitch of the lock strike assembly 20 relative to the profile 12 of the door frame 10 is achieved. Finally the lock strike assembly 20 is fixed to the door frame 10 by screwing up to four screws through the four fixing holes 36 and four clearance holes 43 to clamp the lock strike assembly 20 in place.

Where the lock strike assembly 20 comprises multiple vertically spaced packers 40, the manipulation of a cam 60 will need to be performed at each location prior to fixing the lock strike assembly 20 with the door frame 10. Markings on the upper surface of the strike plate 22 indicating the desired pivot angle facilitate this process, as the required angular displacement is typically the same for each cam 60. Furthermore the step of setting the pitch of the lock strike assembly 20 will need to be repeated before finally fixing the lock strike assembly 20 to the door frame 10.

Once assembled the packer 40 and cam 60 are effectively clamped between the strike plate 22 and the profile 12 of the door frame 10 by the four fixing screws, thereby preventing further movement of the packer 40 and cam 60.

Figures 7 to 9B show the lock strike assembly in a second embodiment. The second embodiment is similar to the first embodiment and only the differences from the first embodiment will be described. Equivalent features to that of the first embodiment are given the same reference numerals.

The lock strike assembly 120 of the second embodiment (see figures 7 and 8) comprises a strike plate 122, a packer 140 and a grub screw 150.

The web 130 of the strike plate 122 has two threaded holes 132A and 132B and three location holes 134A, 134B, 134C.

The packer 140 (see figures 9A and 9B) is a rectangular block adapted to fit in the C-section channel of the strike plate 22. Two legs 142, 144 extend from the lower surface 143 of a first edge 147. A self-tapping slot 148 is centrally located proximate to a second edge 145. A locating pin 149 extends from an upper surface 146 proximate to the first edge 147.

The packer 140 may be positioned in the C-section channel of the strike plate 120 in one of three positions, according to the engagement of the locating pin 149 with one of the three close fitting location holes 134A, 134B, 134C which allow lock strike assembly separations of 9mm, 11mm and 13mm respectively, as measured from the second flange 126 of the lock strike assembly to the flange 4 of the door frame 10. In this position the two legs 142, 144 will extend past the depth of the strike plate 122 and engage in the groove 8 of the door frame 10.

The method of installing the lock strike assembly 120 to door frame 10, comprises the steps of selecting the desired separation of second flange 128 of the strike plate 122 from the flange 4 of the door frame 10 according to the 9mm, 11mm and 13mm separation desired, inserting the packer 140 into the C-section channel of the strike plate 122 such that the locating pin 149 engages with the desired location hole 134A, 134B, 134C, engaging the lock strike assembly 20 with the door frame 10 by inserting the two legs 142, 144 in the groove 8 of the door frame 10, pivoting the lock strike assembly 120 about the first flange 128 by screwing the grub screw 150 through the threaded hole 132 of the strike plate 122 and the self-tapping slot 148 of the packer 140. The grub screw 150 protrudes through the bottom of the lock strike assembly 120 to provide a support to ensure that desired pitch of the lock strike assembly 120 relative to the profile 12 of the door frame 10 is achieved. The lock strike assembly 120 is fixed to the door frame 10 by screwing up to four screws through the four fixing holes (not shown) of the lock strike assembly 120.

Figures 10A and 10B show the lock strike assembly in a third embodiment. The third embodiment is similar to the second embodiment and only the differences from the second embodiment will be described. Equivalent features to that of the second embodiment are given the same reference numerals, prefixed by a ‘2’ instead of a ‘1’ to indicate they are of the third embodiment.

The lock strike assembly 220 of the third embodiment comprises a strike plate 222, a packer 240 and a grub screw 250.

The web 230 of strike plate 222 has one threaded hole 232 and three location holes defined by a single punched detail 134. The three location holes are of the same diameter of those of the strike plate 122 of the second embodiment, however all three are aligned along an axis perpendicular to the longitudinal axis 224 of the strike plate 222 and the separation of their centres is less than their diameter, resulting in a partial overlap.

The oblong shape of the self-tapping slot 248 allows the packer 222 to be aligned with its pin 149 inserted into any one of the three location holes of the single punched detail 234, whilst still allowing grub screw 250 to be fixed through threaded hole 232 of the strike plate 220 and engage with the packer 240. This arrangement provides three distinct lateral alignments for the lock strike assembly 220.

The strike plate according to the second and third embodiment of the invention may of course have more than three pinholes.

The dimensions herein described are with reference to an exemplar uPVC door, however it is reasonable to expect anyone skilled in the art to appreciate that many different dimensions could be applied to the principle without diverging from the invention as presented. The strike plate assemblies herein described may be supplied as a packet of loose parts or as a sub-assembly.

Claims (23)

Claims

1. A lock strike assembly for a door frame and comprising: a strike plate, a packer and a grub screw, said strike plate comprising a C-section channel with a first flange and a second flange separated by a web, said strike plate having a threaded hole through the web, said packer having a plain hole for self-tapping by said grub screw, and said packer adapted to fit within said C-section channel in use between said web and a doorframe such that said plain hole and said threaded hole are aligned, and said grub screw being engageable in the threaded hole; wherein pitch adjustment of the assembly relative to a door frame is achieved through pivoting of the assembly about an edge of the first flange of the strike plate by screwing the grub screw through the threaded hole and the plain hole, and wherein the assembly further comprises a protrusion, lateral positioning of the assembly relative to the door frame being achieved through abutment of said protrusion with the door frame.

2. A lock strike assembly according to claim 1, in which said plain hole in said packer is elongate.

3. A lock strike assembly according to claim 1 or claim 2, in which the packer has a clearance fit fixing hole and the strike plate has a fixing hole.

4. A lock strike assembly according to any of claims 1 to 3, in which the packer has a pin, and the strike plate has a pinhole in the web thereof, the lateral positioning of the packer relative to the strike plate being achieved by engaging the pin in the pinhole.

5. A lock strike assembly according to claim 4, in which the strike plate has a plurality of pinholes, such that a multitude of lateral positions of the packer relative to the strike plate may be achieved.

6. A lock strike assembly according to claim 5, in which the plurality of pinholes is provided in a single punched detail.

7. A lock strike assembly according to any of claims 1 to 6, in which the packer is rectangular in form, having two of said protrusions, the protrsuions comprising two legs at two corners on the same side extending towards a door frame in use.

8. A lock strike assembly according to any of claims 1 to 3, in which the protrusion is a cam.

9. A lock strike assembly according to claim 8, in which the cam is arranged to be actuated through a cam actuation hole in the web of the strike plate.

10. A lock strike assembly according to claim 9, in which the cam actuation hole and the threaded hole are aligned perpendicularly from the first flange of the strike plate.

11. A lock strike assembly according to any of claims 8 to 10, in which the pivoting of the cam is restricted.

12. A lock strike assembly according to claim 11, in which the pivoting of the cam is restricted to ±75° by the packer.

13. A lock strike assembly according to any of claims 8 to 12, in which a visual indicator on the strike plate indicates the degree to which the cam is pivoted.

14. A lock strike assembly according to any of claims 1 to 3 and 8 to 13, in which the packer is U-shaped in form, having a central portion separating two arms.

15. A lock strike assembly according to claim 14, in which the protrusion is located between the two arms of the packer.

16. A lock strike assembly according to claim 14 or claim 15, in which the packer has four clearance holes, two located on each arm of the packer.

17. A lock strike assembly according to any preceding claim, in which the threaded hole in the strike plate is located closer to the second flange than the first flange.

18. A lock strike assembly according to any preceding claim, in which the strike plate includes more that one location for a packer, and a plurality of packers.

19. A method of installing the lock strike assembly of any preceding claim to a door frame, said method comprising the steps of (a) aligning the longitudinal axis of the strike plate with a vertical surface of the door frame; (b) setting the lateral positioning of the lock strike assembly relative to the door frame by positioning the protrusion relative to the strike plate; (c) abutting the protrusion against a groove of the door frame; (d) pivoting the lock strike assembly about the first flange by screwing the grub screw through the threaded hole of the strike plate and the plain hole of the packer such that the grub screw protrudes through the bottom of the lock strike assembly to abut the frame and set the desired pitch of the lock strike assembly relative to the frame; and (e) fixing the lock strike assembly to the door frame.

20. A method according to claim 19, wherein the lateral position setting step (b) includes selecting the appropriate packer orientation such that when the protrusion is engaged in the groove the second flange of the strike plate is the desired distance from the flange of the door frame.

21. A method according to claim 19, wherein the lateral position setting step (b) includes rotationally manipulating a cam using a key such that when the protrusion in the form of an offset peg is engaged in the groove the second flange of the strike plate is the desired distance from the flange of a door frame, and wherein step (e) includes screwing four screws through the four clearance holes of the packer of the lock strike assembly.

22. Method according to claim 20 or claim 21, wherein the lock strike assembly comprises a strike plate with multiple packers and packer mounting locations, such that step (b) to (d) are repeated for each desired packer location.

23. A door with a lock strike assembly according to any of claims 1 to 18.