GB2346927A

GB2346927A - Actuating mechanism for lock

Info

Publication number: GB2346927A
Application number: GB9925963A
Authority: GB
Inventors: Bernard John Viney
Original assignee: Surelock McGill Ltd
Current assignee: Surelock McGill Ltd
Priority date: 1998-11-27
Filing date: 1999-11-02
Publication date: 2000-08-23
Anticipated expiration: 2019-11-02
Also published as: GB9925963D0; GB2346927B; GB9825917D0

Abstract

An actuating mechanism 10 has a housing with a stainless steel cylindrical guard portion 20 and a face portion 30. A Euro-profile cylinder 80 is mounted to the face portion 30 of the mechanism 10, and is spaced from the inside wall of the guard portion 20 by grub screws 90, 95. These prevent relative movement between the cylinder 80 and guard portion 20 when an axial force is applied. The face portion 30 forms a blind face to cover and protect the cylinder 80 from attack, which is possible because the cylinder 80 can be loaded from the rear of the guard portion 20 and affixed by the grub screw 95. The rotor may further be protected by an anti-drill disk between the rotor 80 and face portion 30. Turning the rotor 80 with a key causes a cam 120 to engage with an arm 240 which in turn operates a surface mounted lock.

Description

ACTUATING MECHANISM FOR LOCK This invention relates to an actuating mechanism, in particular for use with a surface-mounted lock.

Mortice locks are well known for installation into door frames. However, their installation weakens the door frame and allows them to be broken or damaged by application of force to the lock mechanism or door.

Surface-mounted locks are mounted against a plane surface of the door rather than into an edge of it. A rim cylinder or the like passes through a hole in the body of the door and engages the surface mounted lock on the other side of the door. Once again, however, such locks are in general relatively easy to attack by force, for example by striking the cylinder with a hammer or drilling out. Often, by applying force to the door, the frame thereof may be broken. For increased security, a number of surface-mounted locks may sometimes be used around the perimeter of a door frame.

To improve damage resistance, cylinder guards have been employed in connection with various rim cylinders.

However, each of these arrangements suffers from the requirement to load the cylinder through the front of the cylinder guard. This in turn allows the front of the rim cylinder to be attacked with a punch or the like.

According to the present invention, there is provided an actuating mechanism comprising: a housing; a cylinder mounted within the housing in fixed relation thereto ; a rotor rotatable relative to the cylinder and housing ; and a cam arranged to rotate with the rotor and adapted to engage a bolt actuator of a surface mounted lock.

Mounting the cylinder within a separate housing protects the cylinder from attempts to break the actuating mechanism by application of force.

Furthermore, the use of such a cylinder and cam arrangement rather than the tang found in typical rim cylinders permits the actuating mechanism to actuate a surface mounted lock.

In the preferred embodiment, the cylinder is of the well-known Euro-profile type. Such a cylinder has previously been used for mortice locks. However, its use for actuating a surface mounted lock provides a number of advantages. For example, the actuating mechanism can be of a single size yet can actuate surface mounted locks through doors of different thicknesses. Previously, actuating mechanisms of differing lengths were necessary.

The cylinder may be attached to the housing via an attachment member such as a screw, bolt or rivet. This further secures the cylinder in fixed relation to the housing to increase strength and resistance to forced entry.

The base portion of the Euro-profile cylinder is preferably received within a channel formed in the housing, the attachment member passing through the walls of the channel and into the base part of the cylinder to attach the cylinder to the housing. This allows the cylinder to be fixed in place within the housing from the rear thereof. The advantage of this is that a robust front face to the housing may be provided, which preferably extends in front of a part of the cylinder.

The cylinder is thereby effectively protected from attack via the front of the housing.

Preferably, the cylinder is spaced from at least one wall of the housing, the lock further comprising a support for supporting the cylinder relative to the housing. The support may, for example, comprise a pin or grub screw which passes through the wall of the housing and into abutment with the cylinder.

Preferably, the housing comprises a cylindrical guard member receivable by an aperture in a door, and a face member adapted to abut against a door face. More preferably, the housing is cast in one piece out of stainless steel or the like.

The rotor may have a keyslot in a front end thereof. This may receive a key which allows the rotor to be rotated.

In a preferred aspect of the invention, the lock further comprises a guard plate arranged to cover at least a part of the front end of the rotor. The guard plate may be received between the cylinder and the housing.

Such a guard plate acts to minimize access to the rotor and cylinder.

This in turn reduces the risk of the rotor or cylinder being broken or punched out by striking the rotor with an implement.

Preferably, the guard plate comprises a disc having a guard slot therein, the guard slot being alignable with the keyslot to permit a key to be received within the rotor. The guard slot when aligned with the keyslot allows a key to be inserted to rotate the rotor.

However, the majority of the rotor, which surrounds and defines the keyslot, is protected. Thus, broad headed implements such as chisels cannot be made to strike the rotor with significant force.

The guard plate may be freely rotatable relative to the housing, and, optionally, further freely rotatable relative to the rotor. This is particularly preferred as any attempt to drill out the rotor simply results in rotation of the guard plate relative to the housing, rather than cutting of the rotor. Such an advantage is particularly conferred when the guard plate is formed of a hardened material such as case-hardened mild steel.

The invention also extends, in a preferred embodiment, to such an actuating mechanism in combination with a surface mounted lock, the surface mounted lock comprising an enclosure mountable to a door face, the enclosure having a bolt connected to a bolt actuator, the bolt actuator being engaged, in use, by the cam of the surface-mounted lock such that rotation of the cam moves the bolt via the bolt actuator.

Preferably, the enclosure is elongate. A handle, independently operable to move the bolt, may also be provided.

The combination of the actuating mechanism with such a surface mounted lock is particularly advantageous. Previously, surface-mounted locks have used a relatively small backplate screwed to the rear of the door in the vicinity of the lock cylinder. This can relatively easily be dislodged by applying force to the front of the actuating mechanism. The preferred elongate surface mounted lock, on the other hand, extends away from the actuating mechanism itself.

Preferably, heavy-duty screws affix the surface mounted lock to a door below an aperture cut for the actuating mechanism. Thus, when a force such as a hammer blow is applied to the front of the actuating mechanism (where the key may be inserted), the force of the blow is spread along the door rather than being transmitted directly to the catch or lock on the other side of the door. It is thus extremely difficult to dislodge the surface mounted lock from the rear of the door by applying force to the front thereof.

The invention may be put into practice in a number of ways, one embodiment of which will now be described by way of example only and with reference to the following Figures, in which: Figure 1 shows a section through an actuating mechanism embodying the present invention; Figure 2 shows a rear view of the actuating mechanism of Figure 1; Figure 3 shows a front view of the actuating mechanism of Figure 1; and Figure 4 shows, in partial section, the actuating mechanism of Figures 1 to 3 mounted through a door for operation of a surface mounted lock.

In the following, the terms front'and rear'are used. It is to be appreciated that these are merely terms to aid description and, unless the context otherwise requires, should not be considered limiting.

Referring first in particular to Figures 1 and 2, an actuating mechanism 10 is shown. The mechanism comprises a housing having a cylindrical guard portion 20 and a face portion 30. The housing is typically cast in one piece from stainless steel. For example, an investment casting process can be used.

As may be seen from Figure 1, the face portion 30 of the housing is frusto-conical. The cylindrical guard portion 20, however, is hollow, and has an outer wall which, in section, circumscribes approximately three quarters of a circle. The upper part of the circumference of the cylindrical guard portion 20 is of generally uniform thickness, as seen in Figure 2.

Towards the lower part of the circumference of the cylindrical guard portion 20, however, the outer wall has a waist portion of greater radial thickness. The waist portion is drilled and threaded to form holes 50 to receive fixing screws (not shown in Figure 2).

Slots 60 are formed in the lower circumference of the wall of the cylindrical guard portion 20, again as shown in Figure 2. The slots 60 define between them an axially extending, generally U-shaped rib 70. The purpose of the rib 70 will be described below.

Mounted to the face portion 30 of the mechanism, and extending generally coaxially within the cylindrical guard portion 20, is a cylinder 80 which is typically of the Euro-profile type, well known to those skilled in the art. Such a cylinder consists of a right cylindrical barrel on an elongate U-shaped base. The cylinder 80 is spaced from the inside of the wall of the cylindrical guard portion 20. A grub screw 90 is inserted through a hole (not shown) through the upper circumference of the wall of the cylindrical guard portion and into abutment with the barrel of the cylinder 80. Likewise, a second grub screw 95 passes through a hole 105 in the wall of the U-shaped rib 70, through a corresponding hole (not shown) in the elongate base of the cylinder 80, and into a further hole (also not shown) in the other side of the U-shaped rib 70. Of course, rather than a grub screw, the arrangement could equally well be riveted or held with a bolt.

The first grub screw 90 supports the cylinder relative to the cylindrical guard portion 20 when a radial force is applied to the cylinder. The second grub screw 95 prevents relative axial movement between the cylinder 80 and cylindrical guard portion 20 should an axial force be applied to the lock. It also further assists the first grub screw by preventing radial movement.

Referring again to Figure 2, the barrel of the cylinder 80 includes a rotor 100 having a keyslot 110 formed therein. The rotor 100 is freely rotatable relative to the cylinder 80 and cylindrical guard portion 20 when the correct key is inserted in the keyslot 110.

Integral with the rotor 100 is a cam 120. The cam extends radially beyond the diameter of the rotor 100 and rests in an axial recess formed in the elongate base of the cylinder 80. However, when the correct key is inserted into the keyslot 110, the rotor 100 and cam 120 are able to rotate within the cylindrical guard portion 20, as seen in Figure 2.

The internal wall of the cylindrical guard portion 20 has a stop 300 formed thereon, diametrically opposed to the U-shaped rib 70. As will be explained in further detail in connection with Figure 4, the cam 120 engages with an elongate arm 240 to actuate a surface-mounted lock 200. The stop 300 constrains rotation of the cam 120 to slightly less than 180 , the elongate arm 240 may be bent.

Figure 3 shows a front view of the lock mechanism of Figures 1 and 2. It will be seen that the face portion 30 forms a blind face to cover and protect the cylinder 80. This is particularly advantageous over prior art mechanisms which include cylinders having tangs. Such cylinders must be loaded into a housing from the front in order to allow the cylinder to be fixed in place relative to the housing from the rear.

This in turn prevents the provision of a blind front face.

By contrast, the cylinder 80 of the present mechanism can be loaded from the rear and affixed in place using the radially directed grub screw 95.

A further advantage of this arrangement is that an anti-drill disc 130 may be employed to protect the rotor 100. As may better be seen from Figure 1, the antidrill disc is freely rotatable but is held, axially, in place between the cylinder 80 and a lip formed in the face portion 30 of the lock. It will be understood from the foregoing that the provision of an effective antidrill disc 130 is facilitated because a blind face may be used on this mechanism.

Referring again to Figure 3, it may be seen that the anti-drill disc 130 has a slot formed in it. The slot is of sufficient width that, when the anti-drill disc and hence the slot is rotated into registry with the keyslot 110 in the rotor 100, a key may pass through the anti-drill disc and into the keyslot.

The purpose of the anti-drill disc is to prevent damage to the rotor 100 by unauthorised persons. The anti-drill disc 130 is preferably formed of casehardened mild steel (zinc coated to prevent rusting) which will resist an ordinary drill bit. Also, because the anti-drill disc 130 floats in the recess formed between the lip 140 and the cylinder 80, attempting to drill the anti-drill disc will simply cause it to rotate. If axial force is applied to the anti-drill disc 130, such as by a hammer blow, then the force is spread across the disc itself, and a significant proportion of the force is not then transmitted to the rotor. It will be appreciated that, in order to apply an axial force directly to the rotor, a relatively thinbladed instrument, able to pass through the slot in the anti-drill disc, must be used. This also reduces the maximum force which can be applied.

Figure 4 shows, in partial section, the actuating mechanism described above when mounted for operation, through a door, of a surface mounted lock. Features common to Figures 1 to 4 are indicated with like reference numerals.

To fit the actuating mechanism 10, an aperture 145 is cut through a door 150. Normally, but not exclusively, the door is wooden. The diameter of the aperture 145 to the door is slightly larger than the outer diameter of the cylindrical guard portion 20 of the lock.

As may be seen from Figure 4, the front of the aperture is stepped or chamfered to receive the rear surface 40 of the face portion 30.

In the arrangement shown in Figure 4, a template 160 is affixed to the rear of the door 150. To hold the lock 10 in place in the aperture 145, screw holes (not shown in Figure 4) are provided which align with the holes 50 cut into the waist portion of the cylindrical guard portion 20. Tightening of the screws into the holes 50 compresses the template 160 against the rear of the door 150 and simultaneously compresses the rear surface 40 of the face portion 30 against the recess in the front of the door 150.

Affixed to the template 160 is a surface mounted lock indicated generally at 200. The particular lock mechanism mechanism shown is described in more detail in British Patent Application No. GB 9725784.4, in the name of Surelock McGill Limited and will not be described in detail. In brief, however, the mechanism 200 allows a deadbolt 210 to be operated by rotation of a first handle 220, whilst rotation of a second handle 230 does not operate the deadbolt 210 unless a key 170 is inserted into the lock 10 and turned. Such a surface mounted lock 200 is therefore particularly useful for emergency exits, where it may be important to allow the door to be opened from one side (usually the inside) without a key, but to prevent access from the other side (usually the outside) without a key.

When the key 170 is inserted into the keyslot 110 of the actuating mechanism, and rotated, the cam 120 also rotates until it contacts an elongate arm 240 which extends generally coaxially with the lock 10 from the surface mounted lock 200. In the example shown, the cam 120 is rotated anti-clockwise as viewed in Figure 2, and the key 170 is therefore turned clockwise. Once the cam 120 touches the elongate arm 240, further anti-clockwise rotation lifts the arm 240 in the direction of the arrow A in Figure 4. This in turn lifts a co-operating deadbolt actuator 250 in the surface mounted lock 200 to release the deadbolt. Depending on whether the door is to open inwards or outwards, a socket or keep plate may be mounted within or upon a door frame. Such an arrangement will be well known to those skilled in the art and will not be described in further detail.

Although the actuating mechanism has been described in conjunction with a surface mounted lock as described in GB-9725784.4, it will be appreciated that this is merely a preferred application, and that the lock mechanism could be used with any other suitable lock whilst still providing the security advantages outlined above. Furthermore, it will be appreciated that the actuating mechanism can be installed equally well on the "inside"of a door (to stop unauthorised exit) or on the "outside"thereof to prevent unauthorised entrance.

Claims

CLAIMS:

1. An actuating mechanism for use with a surface mounted lock, comprising: a housing; a cylinder mounted within the housing in fixed relation thereto; a rotor rotatable relative to the cylinder and housing; and a cam arranged to rotate with the rotor and adapted to engage a bolt actuator of a surface mounted lock.

2. An actuating mechanism as claimed in claim 1, further comprising an attachment member to attach the cylinder to the housing.

3. An actuating mechanism as claimed in claim 2, in which the cylinder is a Euro-profile cylinder.

4. An actuating mechanism as claimed in claim 3, in which a base portion of the cylinder is received within a channel formed in the housing, the attachment member passing through the walls of the channel and into the base portion of the cylinder to attach the cylinder to the housing.

5. An actuating mechanism as claimed in claim 4, in which the attachment member is a screw, the screw passing through an aperture through the wall of the channel, and into a corresponding threaded aperture in the base portion of the cylinder.

6. An actuating mechanism as claimed in any one of the preceding claims, in which the cylinder is spaced from at least one wall of the housing, the actuating mechanism further comprising a support for supporting the cylinder relative to the housing.

7. An actuating mechanism as claimed in any one of the preceding claims, in which the housing comprises a cylindrical guard member receivable by an aperture in a door, and a face member adapted to abut against a door face.

8. An actuating mechanism as claimed in claim 7, in which the face member extends in front of a part of the cylinder.

9. An actuating mechanism as claimed in claims 1 to 8, in which the rotor includes a keyslot in a front end thereof.

10. An actuating mechanism as claimed in claim 9, further comprising a guard plate arranged to cover at least a part of the front end of the rotor.

11. An actuating mechanism as claimed in claim 10, in which the guard plate is received between the cylinder and the housing.

12. An actuating mechanism as claimed in claim 10 or claim 11, in which the guard plate comprises a disc having a guard slot therein, the guard slot being alignable with the keyslot to permit a key to be received within the rotor.

13. An actuating mechanism as claimed in any one of claims 10 to 12, in which the guard plate is freely rotatable relative to the housing.

14. An actuating mechanism as claimed in claim 13, in which the guard plate is further freely rotatable relative to the rotor.

15. An actuating mechanism as claimed in any one of the preceding claims, in combination with a surface mounted lock, the surface mounted lock comprising an enclosure mountable to a door face, the enclosure having a bolt connected to a bolt actuator, the bolt actuator being engaged, in use, by the cam of the lock mechanism such that rotation of the cam moves the bolt via the bolt actuator.

16. An actuating mechanism in combination with a surface mounted lock substantially as herein described with reference to Figure 4.

16. The combination of claim 15, in which the enclosure is elongate.

17. The combination of claim 15 or claim 16, further comprising at least one handle independently operable to move the bolt.

18. An actuating mechanism substantially as herein described with reference to any one of the accompanying drawings.