GB2456530A

GB2456530A - Lock cylinder guard with reducible distance between opposing portions

Info

Publication number: GB2456530A
Application number: GB0800764A
Authority: GB
Inventors: David Andrew Isley; Richard John Emerson
Original assignee: Securistyle Ltd
Current assignee: Securistyle Ltd
Priority date: 2008-01-16
Filing date: 2008-01-16
Publication date: 2009-07-22
Anticipated expiration: 2028-01-16
Also published as: GB2456530B; GB0800764D0

Abstract

The invention provides a lock cylinder guard 1 wherein a distance between opposing portions 1a, 1b of the guard may be reduced. The opposing portions 1a, 1b may be pulled together in order to clamp the lock cylinder 3 using a clamping screw 6. This may tighten the fit of the guard 1 to the lock cylinder 3. The guard may have an opening 2 for receiving the lock cylinder 3 that has a surface that is movable towards the cylinder. The lock cylinder guard 1 may be interengagable with a handle portion, possibly using a system of interengagable locking members such as serrations 11.

Description

1

2456530

A Guard

This invention relates to improved components for lock assemblies. One aspect of the invention relates to lock cylinder guards having improved means of engagement with lock cylinders. In a further aspect, the invention relates to lock cylinder guards and to 5 handle portions with improved means of interengagement. In further aspects, the invention relates to methods of engaging a lock cylinder guard with a lock cylinder, methods of interengaging a lock cylinder guard with a handle portion, and methods of attaching a lock cylinder to a handle portion, in particular, methods of assembling lock assembly components, comprising a lock cylinder, a lock cylinder guard and a handle 10 portion.

It is desirable that lock and handle assemblies, e.g., on doors, especially on doors in buildings, or other forms of gates, hatches, lids, etc., should be as robust as possible, in order to maximise their resistance to forced opening and also to wear over time, for 15 instance if they are subjected to frequent and vigorous use. The strength of such assemblies depends upon the manner in which their individual components are affixed to each other. Moreover, the construction and assembly / fitting of the components should be as simple as possible, both in order to minimise production costs and to ensure that the procedure for assembly / fitting of the components is rapid, easy and intuitive.

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It is particularly desirable to provide a system of components in which the means for attachment of the various components is strengthened in multiple ways and at multiple locations, in order to maximise strength and stability overall. The benefit of a strong engagement between two given components may be limited if a weakness elsewhere in 25 the construction of the assembly can be exploited for forced opening and/or limits the lifespan of the assembly overall.

In the prior art, lock cylinder guards are commonly attached to the lock cylinder by means of small grub screws {i.e., set screws) which need to be inserted through small 30 holes in the sides of the guard. With such conventional lock cylinder guards, the individual fitting the door is required to make indentations in the side of the lock cylinder to provide positions for the grub screws to "bite". The grub screws, or the

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indentations made to receive them, also have the disadvantage that they may affect the integrity of the cylinder. Moreover, grub screws do not generally provide an efficient fastening action. They will generally resist only relatively light loads and forces. One of the potential weak points in a conventional lock assembly is thus the engagement 5 between the lock cylinder guard and the lock cylinder.

In conventional lock assemblies, lock cylinder guards and door handle bases have not been provided with separate means of interengagement. An intruder wishing to forcibly dismantle parts of a lock-and-handle assembly may thus exploit the weakness or lack of 10 the interconnection between the lock cylinder guard and the handle base in such conventional constructions and gain relatively easy access to the lock.

The present invention aims to address the problems described above by providing improved lock assembly components, preferably for doors, more preferably for doors in 15 buildings. The invention provides improved lock cylinder guards and improved handle bases. The strong, simple and rapid attachment of lock cylinder guards to both lock cylinders and handle bases according to the present invention provides improved lock assemblies overall.

20 In one aspect, the invention provides a lock cylinder guard wherein a distance between opposing portions of the guard may be reduced. Preferably, the distance between the opposing portions of the guard may be reduced by joining or pulling together said opposing portions. According to the present invention, said opposing portions are preferably integral parts of the cylinder guard, i.e., portions of a shell that surrounds a 25 lock cylinder when in use. In particular, according to the invention said opposing portions are not screws, in particular they are not grub screws.

The fit of the guard to a lock cylinder placed between said opposing parts may be tightened by said reduction of the distance between the opposing portions of the guard. 30 In preferred embodiments, the invention thus provides a lock cylinder guard wherein a distance between opposing portions of the guard may be reduced by pulling together the opposing portions to clamp a lock cylinder.

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Preferably, the portion of the cylinder guard connecting said clamping opposing portions is sufficiently flexible, resilient or sprung to allow the clamping portions to be pulled together to grip a lock cylinder. Said portion connecting the clamping opposing portions may be resiliently open or resiliently closed. Additionally or alternatively, the opposing 5 portions themselves may be flexible, resilient or sprung in order to allow clamping of a lock cylinder.

In a preferred embodiment, the invention thus provides a lock cylinder guard wherein the reduction of the distance between the opposing portions of the guard tightens the fit of 10 the guard to a lock cylinder placed between said opposing parts.

One aspect of the invention is to provide a lock cylinder guard having an opening, cavity or cut-out space for receiving a lock cylinder, a surface of the opening being moveable toward the cylinder to engage the guard with the cylinder. According to the invention, 15 the opposing portions mentioned above may together enclose said opening. The guard is thus preferably engageable with a lock cylinder by moving an inner surface of the guard toward the cylinder.

The lock cylinder guard of the invention preferably engages with a lock cylinder by 20 clamping, i e., by bringing together portions of the cylinder guard around a cylinder, so as to grip firmly the cylinder between opposing portions of the guard. Compared to conventional engagement by means of grub screws, this clamping engagement, between opposing inner surfaces of the cylinder guard, provides significantly increased strength of attachment, and further major benefits in terms of simplicity of construction and ease 25 of fit. Moreover, the clamping engagement avoids any loss of integrity to the cylinder, in particular the need to indent the sides of the cylinder.

Importantly, rather than relying on a relatively weak attachment by small grub screws, a significant portion of the surface area of the guard facing the cylinder is available to 30 enclose and clamp around the cylinder. Tight contact may thus be made between the cylinder and a complementary surface area of the guard. This form of engagement between the guard and the cylinder provides a strong attachment of the guard to the

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cylinder, and makes an important contribution to the resistance, stability and lifespan of the lock assembly as a whole.

In preferred embodiments, the shape of an opening formed within or between opposing 5 portions of the cylinder guard is formed so as to be substantially complementary to a lock cylinder, so that substantially the entire inner surface area of the guard, i.e., the surface area of the guard facing the cylinder and forming the opening, is available for contact with the lock cylinder.

10 Lock cylinder guards of the present invention may readily be used with currently available lock cylinders, which require no alteration in order to achieve a strong and simple interaction with the cylinder guards of the present invention.

Moreover, with the lock cylinder guards of the present invention, the individual fitting 15 the guard does not need to handle, insert and tighten small grub screws. In particular, there is no need to make either holes in the sides of the cylinder guard or indentations in the sides of the cylinder to receive the grub screws. The process of fitting the guard to the cylinder, and thus, eg., the overall process of fitting a lock to a door, is thereby considerably facilitated and accelerated.

20

The lock cylinder guard of the present invention may have clamping means for clamping the guard to the cylinder. Preferably, the clamping means are means for joining together and/or for reducing the distance between opposing portions of the cylinder guard. Preferably, said clamping means allow one or more dimensions of an opening within the 25 cylinder guard to be reduced. The clamping means may thus allow the size, volume, length, width, cross-sectional area, diameter or circumference, etc., of the opening to be varied. Various clamping means may be used. In one preferred embodiment, said clamping means comprise screw and thread means for joining or pulling together opposing portions of the cylinder guard. Clamping means may thus be provided by 30 holes in the opposing portions which allow the opposing portions to be joined or pulled together by a nut and bolt. Clamping means may also be provided by an unthreaded hole in a first portion of the guard and a threaded hole in a second, opposing portion, thus allowing the opposing portions to be joined or pulled together by a single screw.

5

The lock cylinder guard of the present invention preferably comprises an opening forming a channel comprising a terminal opening and a further longitudinal opening extending along the length of channel, and means for varying one or more dimensions 5 (e.g., the size, volume, length, width, cross-sectional area, diameter or circumference, etc.) of the channel by adjusting the relative disposition of the channel portions on either side of the longitudinal opening. Preferably, the means for varying the volume of the channel are clamping means, as described herein above, suitable for enclosing and securing a lock cylinder placed within the channel, between opposing portions of the 10 cylinder guard. Preferably, the one or more dimensions of the channel are adjusted by screw and thread means, though persons skilled in the art will appreciate that other means may equivalently be used.

In preferred embodiments of the invention, the lock cylinder guard may comprise two 15 components. In certain preferred embodiments, discrete components may be joined by clamping means such that they together form opposing portions which clamp around the lock cylinder. In a particularly preferred embodiment of the invention, discrete components of the lock cylinder are arranged such that a reduction of the distance between opposing portions of the guard tightens the fit of the guard to the cylinder at 20 only one end, or a first portion, of the cylinder (see, e.g., Figures 2, 3). In such an embodiment, the opposite end, or a second portion, of the cylinder may be enclosed in a component of the guard that encloses and preferably fits snugly around the lock cylinder, but does not have clamping means. Preferably a pin or bolt connects two lock cylinder guard components (see Figures 2, 3), preferably by screw and thread or equivalent 25 means of interengagement.

According to a further aspect of the invention, the lock cylinder guard of the present invention is interengageable with a handle portion by means of a system of interengageable locking members. Suitable interengageable locking members may be 30 formed e.g., by serrations on both the guard and the handle portion, a system of interengageable or corresponding teeth and notches, or ribs, tabs, ridges, grooves, recesses, pockets, etc.. The guard preferably comprises engaging means for engagement with a handle portion, wherein said engaging means comprise a system of corresponding

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teeth and notches. Preferably, the lock cylinder guard of the invention is thus a toothed lock cylinder guard. Preferably, said handle portion is a handle base, e.g., a door handle base.

5 According to certain embodiments of the invention, a cylinder guard may be interengaged with a handle portion by means of a single tooth (or equivalently a rib, a tab, etc.) and a corresponding notch (or equivalently, groove, recess, pocket etc.) to receive the tooth. As persons skilled in the art will understand, the dimensions and disposition of the serrations (e.g., teeth and notches) are not particularly limited, 10 provided they allow interengagement of a lock cylinder guard with a handle portion.

In order to achieve interengagement of a lock cylinder guard according to the invention with a handle base of the invention, the lock cylinder guard may, e.g., carry teeth and the handle base may have notches to receive the teeth, or vice versa. Alternatively, both the 15 lock cylinder guard and the handle base may have both teeth and notches.

In preferred embodiments, the number of teeth and corresponding notches is chosen so as to allow the lock cylinder initially to be inserted into a handle portion in a position and orientation substantially similar to the final, interengaged position, and then to latch 20 the cylinder guard into its final, interengaged position within the handle base by only a relatively minor displacement. Generally, smaller teeth allow simpler and smoother displacement of the cylinder in the final latching step of interengaging a cylinder guard and a handle base according to the invention. However, the skilled person will understand that, depending on the materials used, the dimensions of the teeth should be 25 sufficient to provide a requisite strength of interaction.

The system of teeth and notches may thus comprise or consist of one or more, preferably between 4 and 7, teeth and/or notches on one or more sides of the cylinder guard, in a position suitable to provide interengagement with corresponding teeth and/or notches on 30 a handle portion.

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According to the invention, said teeth and/or notches may be situated anywhere on a cylinder guard or a handle portion, but are preferably situated along and/or located suitably for interaction with a longest dimension of a discrete guard component.

5 In accordance with the aspects of the invention described above, the present invention also provides a handle base, preferably a door handle base, for use with the lock cylinder guard of the present invention.

Preferably, said handle base may be engaged by inserting the guard into the base and 10 subsequently translating the guard within the base so as to interlock the teeth and the notches.

Conversely, the invention also provides a lock cylinder guard for use with the handle base of the present invention.

15

The invention also provides a kit of parts (or a system of components) comprising a lock cylinder guard and a handle base, wherein, preferably, the base and guard are engageable by a system of teeth and notches.

20 The invention thus also provides a lock assembly comprising a lock cylinder guard substantially as described herein, a lock cylinder, wherein the lock cylinder may be a conventional lock cylinder, and a handle base substantially as described herein.

In the kit of parts or the lock assembly according to the present invention, the lock 25 cylinder guard and the handle base may each independently be configured according to any of the embodiments described herein above.

The present invention also provides a method of engaging a lock cylinder guard with a lock cylinder, said method comprising the step of reducing the distance between 30 opposing portions of the guard, thereby tightening the fit of the guard to a lock cylinder placed between said opposing portions.

8

Preferably, the method of the present invention comprises the step of joining together the opposing portions of the guard by clamping means.

The present invention also provides a method of engaging a lock cylinder guard with a 5 lock cylinder, said method comprising the steps of

(a) placing a lock cylinder within an opening in the guard, and

(b) tightening the fit of the guard to the cylinder by moving a surface of said opening toward the cylinder.

10 The present invention also provides a method of interengaging a lock cylinder guard with a handle portion, said method comprising the step of interengaging a system of teeth and notches on the guard and the handle portion.

The present invention also provides a method of attaching a lock cylinder to a handle 15 portion, said method comprising the steps of

(a) placing a lock cylinder between opposing portions of a lock cylinder guard,

(b) reducing the distance between said opposing portions, thereby tightening the fit of the guard to the cylinder, and

20 (c) interengaging a system of teeth and notches on the guard and the handle portion.

The above method of attaching a lock cylinder to a handle portion according to one embodiment of the invention is not limited by any particular order of steps (a), (b), (c), 25 though in certain preferred embodiments, step (c) may precede step (b).

Preferred embodiments and examples of the invention will now be described in greater detail with reference to the accompanying drawings, in which:

30 Figure 1 shows a preferred embodiment of a lock cylinder guard of the invention in various views (panels A and B: perspective views; panels C and D: end elevation views; panel E: side elevation; panel F: top elevation).

Figure 2 shows a guard of the invention clamped to a lock cylinder. A clamping outer guard and a non-clamping inner guard are shown.

Figure 3 shows an exploded view of the assembly of Figure 2.

Figure 4 shows a cylinder guard of the invention when inserted into a door handle 5 base. The teeth of the guard and the handle base are aligned, to allow insertion of the guard into the handle base, but the guard has not yet been slid into place (downwards) to allow the teeth on the guard and the handle base to interlock.

Figure 5 shows the guard and handle base of Figure 4 when interengaged 10 Figure 6 shows a lock cylinder and cylinder guard of the invention assembled onto a door handle base, with a handle.

A preferred embodiment of a lock cylinder guard of the invention (1) is shown in Figure 1. Opposing portions (la and lb) of the cylinder guard enclose an opening (2), which 15 receives one end of a lock cylinder (3). The shape of the opening is substantially complementary to a substantial part of the surface of the lock cylinder that is enclosed within the guard (see Figures 2 and 3). In the embodiment shown in the figures, the opening (2) is complementary to the greater part of the surface of the lock cylinder that is enclosed within the guard. In particular, it is complementary to the portion (3a) of the 20 cylinder (3) that receives the key and also to a substantial part of a further portion (3b) of the cylinder.

In the embodiment shown in the figures, opening (2) widens into a cut-out area (2a) which provides space around portion (3b) of the lock cylinder for the passage of a bolt 25 (4) connecting an outer lock cylinder guard component (1) to an inner lock cylinder guard component (10, see Figures 2 and 3). Bolt (4) terminates in threaded hole (5) . Preferably, said hole (5) penetrates the guard only partially.

30

When fitted at an entrance of a building, "outer" lock cylinder guard component (1) is intended to face toward the outside of the building (see also Figure 6), whereas "inner" lock cylinder guard component (10) is intended to face the interior of the building.

10

In component (1), the portion surrounding hole (5) and connecting opposing portions (la) and (lb) is resilient, i.e., sufficiently flexible to allow a clamping movement of portions (la) and (lb). Additionally or alternatively, sides (la) and (lb) themselves are sprung or resilient.

5

Opposing portions (la) and (lb) are clamped around the lock cylinder by tightening a clamping screw (6) to connect holes (7a and 7b). In a particularly preferred embodiment, one hole (e.g., 7a) is unthreaded and another (e.g., 7b) is threaded. These holes are suitably located in the opposing portions (la) and (lb) to allow the distance

10 between the opposing portions of the guard to be reduced, and the fit of the guard to a cylinder contained therein to be tightened by the action of the clamping screw (6). The tightening of the screw (6) ensures that the guard clamps securely around the lock cylinder. This arrangement provides for particularly simple, rigid and secure clamping means.

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In the embodiment shown in Figure 2, the inner part (10) of the lock cylinder guard is rigid and does not feature the clamping action of opposing portions as described and shown for the outer part (1). However, part (10) is stably interconnected to part (1) and thus to the lock cylinder by bolt (4).

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In the preferred embodiment shown in the figures, the lock cylinder guard of the invention combines both a clamping action for engagement with a lock cylinder and advantageous means for interengagement with a handle portion (handle base (15), see Figures 4, 5 and 6). In embodiment shown in the figures, said means for

25 interengagement are provided by teeth (11) arranged along the two longest outer edges of opposing portions la and lb of the cylinder guard. In the figures, six teeth along each side of the cylinder guard are shown, but their number and disposition could be varied, as described above or as would be apparent to persons skilled in the art.

30 A clamping lock cylinder guard according to the invention may also be provided without teeth or any other particular means of interengagement with a handle base.

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In the embodiment shown in Figures 4 and 5, the teeth (11) on the cylinder guard latch or lock behind corresponding teeth (12) on a door handle base (15). The serrations (notches) in the door handle base are arranged such that the cylinder guard may initially be inserted into the handle base by aligning the teeth on the guard with the gaps between 5 the teeth on the handle base and slotting the guard's teeth through the gaps in the handle base. The guard and the handle base are then easily and stably interengaged by sliding the guard further into the handle base . The teeth on the cylinder guard are thereby placed within notches provided by the space behind the teeth on the handle base, locking the cylinder guard into position. The guard and the base are thereby readily 10 interengaged in a stable and secure manner which presents a significant obstacle to any attempt, e.g., to open a locked door by removing the handle base from the lock cylinder guard.

In certain preferred embodiments (e.g., as shown in Figures 2 and 3), inner lock cylinder 15 guard (10) is not toothed and is not a clamping cylinder guard.

To incorporate lock cylinder guards of the invention into a lock assembly on a door, the guard (eg., (1)) may in one embodiment conveniently be clamped onto a lock cylinder, preferably using a single screw to tighten the guard onto the lock. The assembled lock 20 and guard may then be fit into a door, whereupon a handle base (15) having a handle (16) is applied to the door and interengaged / interlocked with the cylinder guard as described above. Finally, the handle base is screwed to the door, using threaded holes 14.

25 Alternatively, depending on the construction of the particular door, the assembled lock and guard may initially be connected to a door handle base as described above. The lock and guard, firmly attached to the door handle base, are then placed in the appropriate location on the door, and the handle base is screwed onto the door.

30 An internal lock cylinder guard (e.g., (10)) can then be applied to the inside end of the lock cylinder.

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It will of course be understood that the present invention has been described above by way of example only and that modifications of detail can be made within the scope of the appended claims.

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Claims

1. A lock cylinder guard wherein a distance between opposing portions of the guard may be reduced.

2. A lock cylinder guard as claimed in claim 1, wherein the distance between the opposing portions of the guard is reduceable by joining together said opposing portions.

3. A lock cylinder guard as claimed in claim 1, wherein reduction of the distance between the opposing portions of the guard tightens the fit of the guard to a lock cylinder placed between said opposing parts.

4. A lock cylinder guard having an opening for receiving a lock cylinder, a surface of the opening being moveable toward the cylinder to engage the guard with the cylinder.

5. A lock cylinder guard as claimed in claim 4, wherein opposing portions together enclose the opening.

6. A lock cylinder guard as claimed in any of the preceding claims having clamping means for clamping the guard to the cylinder.

7. A lock cylinder guard as claimed in claim 6 wherein said clamping means allow the size of the opening to be reduced.

8. A lock cylinder guard of any as claimed in claims 4 to 7, said opening forming a channel comprising a terminal opening and a further longitudinal opening extending along the length of channel, and means for varying the volume of the channel by adjusting the relative disposition of the channel portions on either side of the longitudinal opening.

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A lock cylinder guard as claimed in any of the preceding claims, wherein the guard comprises two components.

The lock cylinder guard as claimed in claim 9, wherein a reduction of the distance between opposing portions of the guard tightens the fit of the guard to the cylinder at only one end of the cylinder

A lock cylinder guard that is interengageable with a handle portion.

A lock cylinder guard as claimed in claim 11, wherein the guard is interengageable with a handle portion by means of a system of interengageable locking members.

A lock cylinder guard as claimed in claim 12, wherein said interengageable locking members are serrations.

A lock cylinder guard as claimed in claims 12 or 13, wherein said interengageable locking members are interengageable teeth and notches.

A guard as claimed in any of claims 1-10, wherein the guard is interengageable with a handle portion by means of a system of interengageable locking members.

A guard as claimed in any of claims 1-10, comprising engaging means for engagement with a handle portion, wherein said engaging means comprise a system of interengageable locking members.

A guard as claimed in claims 11 or 16, wherein said handle portion is a handle base.

A guard as claimed in claims 11 to 17 wherein said interengageable locking members are situated along a longest dimension of a discrete guard component.

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19. A handle base that is interengageable with a lock cylinder guard by means of a system of interengageable locking members .

20. A handle base as claimed in claim 19 for use with a lock cylinder guard as 5 claimed in any of claims 1 to 18.

21. A handle base as claimed in claims 19 or 20 wherein the guard and the base may be engaged by inserting the guard into the base and subsequently translating the guard within the base so as to interlock the interengageable

10 locking members.

22. A lock cylinder guard as claimed in any of claims 1 to 18 for use with a handle base as claimed in any of claims 19 to 21.

15 23. A kit of parts comprising a lock cylinder guard and a handle base wherein base and guard are engageable by a system of interengageable locking members.

24. A kit of parts comprising a lock cylinder guard as claimed in any of claims 1 to 18 and a handle base as claimed in any of claims 19 to 21.

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25. A lock assembly comprising a lock cylinder guard as claimed in any of claims 1 to 18, a lock cylinder and a handle base as claimed in any of claims 19 to 21.

26. A method of engaging a lock cylinder guard with a lock cylinder, said method

25 comprising the step of reducing the distance between opposing portions of the guard, thereby tightening the fit of the guard to a lock cylinder placed between said opposing portions.

27. A method as claimed in claim 26, comprising the step of joining together the

30 opposing portions of the guard by clamping means.

28.

A method of engaging a lock cylinder guard with a lock cylinder, said method comprising the steps of

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(a) placing a lock cylinder within an opening in the guard, and

A method of interengaging a lock cylinder guard with a handle portion, said method comprising the step of interengaging a system of interengageable locking members on the guard and the handle portion.

A method of attaching a lock cylinder to a handle portion, said method comprising the steps of

(a) placing a lock cylinder between opposing portions of a lock cylinder guard,

(c) interengaging a system of interengageable locking members on the guard and the handle portion.

A method as claimed in claim 30, wherein step (c) precedes step (b).