GB2472271A

GB2472271A - A locking arrangement having an anti-friction component

Info

Publication number: GB2472271A
Application number: GB0913444A
Authority: GB
Inventors: Anthony Lee Hughes
Original assignee: Epwin Group PLC
Current assignee: Epwin Group PLC
Priority date: 2009-07-31
Filing date: 2009-07-31
Publication date: 2011-02-02
Also published as: GB0913444D0

Abstract

A lock, for a window or door, comprising a locking component 6, such as a latch or bolt, and a lock receiving section, such as a keeper, with a strike 7 which receives the locking component 6. A low friction element 20 having a coefficient of friction less than the locking component and the strike is mounted to at least one of the locking component and strike at a position in which they contact. The low friction element may be a patch 20 or a roller (30, fig. 3). The low friction element may be removable mounted and constructed from plastics or bronze wherein the locking component and strike may be metal such as brass or steel. The lock may be used with a window or door having a seal and the presence of the low friction element reduces the operating friction when the locking element moves against the strike, and thus facilitates ease of use of the lock.

Description

A WINDOW OR DOOR LOCK

The present invention relates to windows or doors, more particularly to locks for windows or doors.

For some doors or windows it is desirable to prevent access by the weather, dirt or insects through the gap between the opening part and the fixed part of the door or window, when in the closed position. These doors or windows often have a seal provided. The seal is usually attached along an edge of the fixed part of the door or window. The seal is positioned so that when the opening part is moved to abut the fixed part the seal is compressed along the length of the door or window and there is no access through the door or window for the weather, dirt or insects. The door or window is known as "weather-tight". The seal resists compression and this can make it more difficult to close the door or window and to secure the lock.

Many types of locks are known. Window or door locks comprise a locking component, usually attached to the opening part. The locking component can be reversibly retractable by a variety of means, for example by means of a spring. The mechanism to retract and project the locking component can be through a variety of means and is accessible through one or both sides of the window or door division. A cavity is thus provided in the fixed part of the door or window. When the lock is in the closed or "locked" position the locking component slides into the cavity in the fixed part of the door or window. The cavity may be lined to provide strength for the contact surface with the locking component.

Locks often comprise a receiving section, usually attached to the fixed part of the door or window. The receiving section encloses the cavity for receipt of the locking component when the lock is in the closed position, and has a strike which protects the door or window frame from damage caused by friction when the locking component slides into position. Some strikes have a protrusion into the cavity, which acts as a guide for the locking component into the cavity and provides an additional contact surface for the locking component to traverse. The receiving section may be embedded in the fixed part or opening part of the door or window. Alternatively, the receiving section may be attached to the surface of the fixed part or opening part of the door or window such that it will not interfere with the formation of a tight seal between the opening part and fixed part of the door or window in the closed position.

It is known to improve the smoothness of the fit of the locking component into the strike by the provision of a radius on the locking component and / or a chamfer I lead on the strike, This prevents jarring if the locking component and the strike are slightly out of alignment.

Figs. I a and lb each show part of a conventional door or window in the closed position. In both Figs la and lb the opening part 1 and the fixed part 2 of the window or door are in close conformation and are prevented from abutting by the presence of a seal 3. Both the opening part 1 and the fixed part 2 are in contact with the seal 3. The door or window is held in this conformation by the presence of a lock in a closed configuration.

The lock has a locking component attached to the opening part 1. In Fig la a bolt 4 is shown as an example of a locking component. In Fig. lb a roller 5 is shown as an example of a locking component. Other examples of locking components include a cylindrical pin and a hook. The hook is designed to fit in a groove or over an elevation in the strike protrusion. The presence of the double-headed arrow 6 in Fig la indicates that the locking component is retractable into a cavity within the opening part of the door or window. The movement of the lock bolt 4 into or out of the cavity is often mediated by the movement of a locking arm by the user. Alternatively, the movement of the bolt 4 can be mediated by a spring. In contrast, in Fig lb the roller 5 can be slideable down the edge of the door to enter the cavity from above, or can be slideable up the edge of the door to enter the cavity from below, depending on the lock configuration. The movement of the roller is mediated by the movement of a locking arm by the user. The double-headed arrow 6 in Fig lb indicates that the roller 5 can move vertically relative to the edge of the door.

A strike 7 is mounted onto the fixed part 2 of the window or door. The strike 7 defines an aperture 8 into which the locking component can slide. The strike 7 is located at an equivalent height to the locking component on the opening part I of the window or doors, so that the locking component can move into the aperture 8 in the strike 7. As it does so, the locking component contact surface 9 slides against the strike contact surface 10, that engagement being such that the seal 3 is compressed between the parts 1 and 2. In order to facilitate the movement of the locking component into the aperture 8, there may be corresponding tapers 11, 12 on the locking component and strike 7.

The strike 7 and the locking component are usually made of a metal such as steel or brass. This choice of material is required for locks in which the tight compression of a seal 3 is required. The strike 7 must be of sufficient strength to hold the locking component and opening part 1 of the door or window in place and maintain the pressure to compress the seal 3. However, metal locks have the disadvantage that a very large amount of friction can be generated when the locking component slides across the contact surface into the aperture 8. This, in part, is caused by the resistance of the seal 3 to compression when the locking component engages with the strike 7 and slides into the aperture 8. This increases the relative load and therefore the friction between the two contacting surfaces of the strike 7 and the locking component. The friction and therefore the difficulty in operating the lock is exacerbated when there are multiple locking features.

However, the provision of the tapers 11, 12 can be insufficient to overcome the difficulty in moving and operating the lock. It is known to adjust, the positioning of the strike, relative to the seal 3 on the fixed part 2 of the door or window, such that the opening part does not compress the seal 3 to as great an extent when the locking component is fixed in the receiving section. Thus, the operating friction is reduced. However, this solution is not ideal because it decreases the compression of the seal 3 and leads to poor weathering.

Therefore an alternative Solution is needed to address this problem.

At its most general, the present invention proposes that the strike contact surface and / or the locking component contact surface has an element of reduced friction, relative to the strike and locking component, so that the locking component can slide relative to the strike without requiring excessive force. On the other hand, the rest of the strike and the locking component ensures that the window or door parts are held securely. The invention is suitable for locks containing any locking component known in the art, examples of which include a bolt, a roller, a hook or a cylindrical pin. Where the locking component is a hook the strike protrusion will contain an elevation or a groove in which the hook can lodge.

Thus, according to a first aspect of the present invention, there may be provided a lock for a window or door comprising: a locking component mountable on one part of the window or door; and a lock receiving section mountable on a second part of the window or door, the lock receiving section having a strike for receiving the locking component; wherein the strike has a contact surface which engages the locking component and the locking component has a contact surface which engages the strike, and wherein an element of a coefficient of friction less than the locking component and the strike is mountable to the locking component contact surface and I or the strike contact surface, which low friction element is between the locking component and strike when the locking component contact surface engages the strike contact surface.

The addition of such an element of relatively low frictional resistance (herein after low friction element') reduces the operating friction generated when the locking component contact surface moves against the strike contact surface and thus facilitates ease of use of the lock. The low friction element is made of a low resistance material which contributes to a low sliding coefficient of friction, wherein the low friction element is attached to one or both of the strike contact surface and the locking component contact surface and wherein the strike contact surface and the locking component contact surface are suitable to make contact.

The low friction element is made of a material that is suitable to prevent the build up of friction when the locking component is moved over the inner surface of the strike. This facilitates ease of movement of the locking component into the strike. The low friction element can be made of a metal alloy, such as bronze, when the locking component and at least the contact surface of the strike are of steel or brass. Alternatively, the low friction element may be made of plastic material. Preferably, the low friction element is made of nylon or PTFE composite.

The low friction element can be a patch mounted on or embedded in the strike contact surface and / or the locking mechanism contact surface. The patch must not block the locking component sliding through the strike aperture. The patch can have a flat contact surface for contact with either the locking component contact surface or the strike contact surface, but preferably, the patch contact surface is radiused to further reduce friction as the locking component engages with the contact surface.

The patch may be attached to the strike by, for example, the use of adhesive glue or screws, or by engagement of a projection on the element with a recess in the strike contact surface or the locking component contact surface.

Alternatively, the low friction element may be a roller. This reduces the friction generated because rolling friction is generally less than kinetic friction.

The roller is embedded in the strike contact surface and I or the locking component contact surface, e.g. in a cavity in the strike contact surface and / or the locking component contact surface. The roller can be one or more cylinders or ball bearings. A small contact area of the circumference of the roller is accessible to the locking component as part of the strike contact surface and I or is accessible to the strike as part of the locking component contact surface. The roller must have freedom of rotation about its axis to reduce the friction caused by the movement of the locking component into the strike. Upon the opening part approaching the fixed frame the locking component enters the strike and the roller is engaged. The roller can rotate about its axis in the direction of movement of the locking component and less kinetic energy is converted into thermal energy, facilitating ease of sliding.

The roller can be attached to, or held within, the strike contact surface cavity or the locking component contact surface cavity by any means that will allow the free rotation of the roller about its axis. For example, the roller can be hollow and can rotate about a fixed shaft within the cavity or box. The cylinder can be attached to the walls of the cavity or box by means of one or more sockets on each side of the cylinder into which the shaft can fit.

Alternatively, the roller could have pins on either end, or ends tapered to a point, that can fit and rotate within a socket connected to the strike cavity walls. Alternatively, the roller could be caged within a cavity possessing a smaller aperture at the surface than the width of the roller, such that the roller is unable to escape from the cavity.

The low friction element can be removable from the strike contact surface or the locking component contact surface for replacement. Alternatively, the low friction element can be permanently attached to the strike contact surface or locking component contact surface. Removability of the low friction element accommodates wear or damage to the low friction element and extends the life of the lock.

Where a locking device contains multiple locking components and receiving sections, a low friction element can be attached to some or all of the receiving sections. In addition the lock strike may or may not have a chamfer / lead and / or the locking component may or may not be radiused. The strike can be lubricated by any lubricant known in the art.

According to a second aspect of the present invention there may be provided a window or door comprising: a frame; a movable element mounted in the frame; a seal mounted between the frame and the moveable element; and a lock according to the first aspect mounted with the locking component on one of the frames and movable element and the lock receiving section mounted on the other of the frame and movable element, the lock securing together the frame and movable element when the locking component engages the lock receiving section, with the seal compressed between the frame and movable element.

Embodiments of the invention will now be described with reference to the accompanying drawings, in which: Fig. la is a diagrammatic cross section showing a conventional lock with a strike for a window or door. The locking component is shown as a bolt. This diagram is included for ease of understanding references to parts of the lock as a whole; Fig. lb is a diagrammatic side profile view showing a conventional lock with a strike for a window or door. The locking component is shown as a roller. This diagram is included for ease of understanding references to parts of the lock as a whole; Fig. 2a is a diagrammatic side profile view showing the first embodiment of the present invention with a patch attached to the strike contact surface; Fig. 2b is an enlarged diagrammatic side profile view showing a close-up of the first embodiment of the present invention with a patch attached to the strike contact surface; Fig. 2c is a diagrammatic side profile view showing the first embodiment of the present invention with a patch attached to the locking component contact surface; and Fig. 3 is a diagrammatic plan view showing the contact surface for the locking component or strike in the second embodiment of the present invention.

A first embodiment of the present invention will now be described with reference to Figs 2a and 2b. In this embodiment, the general structure of the window and door parts, seal, locking component and strike are similar to those described with reference to Fig la, so these parts will not be described in more detail now.

In this embodiment, the strike 7 has a patch 20 mounted on the engagement surface 10 so that it faces into the aperture 8. The patch 20 is of a material of a coefficient of friction lower than that of the strike contact surface 10, and also lower than that of the locking component (not shown). Thus, the locking component contact surface 9 can slide over the strike contact surface 10 more easily than in the arrangement shown in Fig 1.

Fig 2b then shows the patch 20 in more detail as can be seen, it consists of an upper plate 21 and a projection 22, which projection 22 is received in a slot 23 in the engagement surface 10. As can be seen from Fig 2b sides of the projection 22 taper outwardly, and the slot 23 tapers in a similar way, such that the projection is narrower at its end adjacent to the plate 21 than at its free end, so that the shape of the projection 22 and slot 23 hold the plate 21 in place on the strike contact surface 10.

The patch may form part or all of the engagement surface 10 of the strike. It should be noted that although the plate 21 shown in Fig 2b is cuboid, it is preferable that it is shaped or radiused to further reduce the friction experience between the locking component and the strike 7.

The choice of material of the patch 20 will depend on the materials of the locking component and strike 7. In practice, those components are usually of steel or brass, in which case the patch 20 may be of bronze, or other soft metal alloy. Alternatively, the patch may be of a plastics material, such as nylon or a PTFE composite. Such a material has a lower frictional resistance than most metals, from which the locking component and strike 7 may be made. Normally, in a lock, the locking component and strike 7 are made of the same or similar materials, but this is not essential.

It can be seen that, in this embodiment, the patch 20 may be removed from the strike 7 by sliding the projection 20 out of the slot 23. This enables the patch 20 to be replaced if it becomes worn or damaged. Alternatively, the patch may be permanently fixed to the strike. This fixation may be by any means known in the art, for example the use of a strong adhesive or nails.

In the above discussion the patch is mounted in a slot in the contact surface of the strike. Alternatively, the patch could be mounted directly onto the strike contact surface. The patch could be fixed to the surface of the strike engagement surface by any means known in the art. For example the patch could be fixed to the strike by strong adhesive.

In the above described embodiment the patch was mounted to the engagement surface of the strike, however, it could be mounted to the contact surface of the locking component 9. Alternatively, a patch could be mounted to both the strike contact surface and the locking component contact surface.

It is also possible for a plurality of patches to be mounted on one or both of the strike contact surface and the locking component contact surface.

In the above discussion the locking component is a bolt. It would also be possible to use a hook, a pin or a roller (see Fig ib). Where the locking component is a pin or a hook the patch may be mounted on either or both the locking component contact surface and the strike contact surface. Where the locking component is a roller the patch can be in the form of a skin that covers part or all of the surface of the roller. Alternatively, where the locking component is a roller the patch, as described in the first embodiment, could be mounted to the strike contact surface.

Another embodiment of the invention is shown in Fig 3. Again, the general configuration of the lock may be the same as shown in Fig Ia, so Fig 3 only illustrates the strike contact surface 10 and low friction element. In this embodiment, the low friction element is a roller 30 mounted in an opening 31 in the strike contact surface 10. The roller is free to rotate, so that as the -10-locking component (not shown in Fig 3) passes over the strike contact surface 10, it will contact the roller and thus friction between the locking component and the strike contact surface 10 is reduced.

As can be seen from Fig 3, the roller 30 is held in the slot 31 because it has a diameter larger than the slot 31. Although not visible in Fig 3, the roller 30 is received in a cavity in the strike 7 below the strike contact surface 10, which cavity has a mouth formed by the slot 31 which is of a sufficient size to hold the roller 30 in place. The roller 30 may have stub axials 32 mounted in bores 33 in the strike 7, to facilitate the rotation of the roller.

Again, the roller may be made from any material which has a lower frictional resistance than the material of the locking component and the strike contact surface 9. In practice, it is probably easiest to make the roller of a plastics material, although again bronze or other metal alloy could be used.

In the above discussion the roller is a cylinder. The roller may also be one ball or a series of roller or ball bearings.

In the above discussion the roller is mounted in an opening in the strike contact surface. It is also possible for the roller to be mounted in an opening in the locking component contact surface instead of the strike contact surface.

Alternatively, one roller could be provided mounted to the strike contact surface and a second roller could be provided mounted to the locking component contact surface. In another possibility multiple rollers could be provided on one or both contact surfaces. The latter possibility is most likely, when the roller consists of ball bearings, rather than a cylinder.

In the above discussion the roller is mounted into a cavity in the strike contact surface and / or locking component contact surface. It is also possible for the roller to be mounted directly onto the strike contact surface or locking component contact surface and not in an opening in the representative contact surface. -11 -

The locking component in the lock of the previously described embodiments that contained a low friction roller is a lock bolt. Alternatively, if the locking component is a cylindrical pin or a hook one or more rollers could also be provided for the strike contact surface and / or the locking component contact surface. If the locking component was a roller (see Fig lb), one or more roller low friction elements could be mounted to the strike contact.

A combination of low friction element types may be provided in the invention.

When the locking component is a bolt, a hook or a cylindrical pin one or more patches could be mounted to the locking component contact surface and one or more low friction element rollers could be mounted to the strike contact surface. Alternatively, when the locking component is a bolt, a hook or a cylindrical pin one or more patches could be mounted to the strike contact surface and one or more rollers could be mounted to the locking component contact surface. Another possibility when the locking component is a bolt, a hook or a cylindrical pin is for one or more patches and rollers to be provided on both the strike contact surface or the locking component contact surface.

When the locking component is a roller (see Fig 1 b) a combination of low friction element types may also be provided in the invention. One possibility is the provision of one or more rollers mounted to the strike contact surface and one or more patches consisting of a skin of low friction material covering part, or one patch of material covering all, of the locking component contact surface. Alternatively, one or more patches and one or more rollers could be provided mounted to the strike contact surface and one or more patches consisting of a skin of low friction material covering part, or one patch of material covering all, of the locking component contact surface.

Some locks may have a plurality of strikes and complementary locking components. It is envisaged that one or more low friction elements as described in any of the above embodiments could be provided for some or all of the strikes or locking components in these locks. -12-

In a further embodiment a window or door may be provided pre-mounted with a lock according to any one of the above embodiments.

Both the presence or absence of a chamfer / lead on a strike or a radius on a locking component may be compatible with any of the above embodiments of the invention. The strike can also be lubricated by any lubricant known in the art. Lubrication is preferably used when the low friction element is a roller bearing. -I *

Claims

-13 -CLAIMS1. A lock for a window or door comprising: a locking component mountable on one part of the window or door; and a lock receiving section mountable on a second part of the window or door, the lock receiving section having a strike for receiving the locking component; wherein the strike has a contact surface which engages the locking component and the locking component has a contact surface which engages the strike; and wherein an element of a coefficient of friction less than the locking component and the strike is mountable to the locking component contact surface and I or the strike contact surface, which low friction element is between the locking component and strike when the locking component contact surface engages the strike contact surface.
2. A lock according to claim 1, wherein said element is a patch mounted on the strike contact surface and / or the locking component contact surface.
3. A lock according to claim 1, wherein said element is a roller mounted on the strike contact surface and / or the locking component contact surface.
4. A lock according to any one of the preceding claims, wherein said element is releasably mounted to the strike contact surface and / or the locking component contact surface.
5. A lock according to any one of the preceding claims, wherein the locking component and at least the contact surface of the strike are of metal and the element is of plastics material.
6. A lock according to any one of claims 1 to 4, wherein the locking component and at least the contact surface of the strike are of brass or steel -14 -and the element is of bronze or other metal alloy of lower frictional resistance than brass or steel.
7. A window or door comprising: s a frame; a movable element mounted in the frame; a seal mounted between the frame and the moveable element; and a lock according to any one of claims I to 6 mounted with the locking component on one of the frames and movable element and the lock receiving section mounted on the other of the frame and movable element, the lock securing together the frame and movable element when the locking component engages the lock receiving section, with the seal compressed between the frame and movable element.
8. A lock for a window or door substantially as herein described, with reference to and as illustrated in Fig 2a, Fig 2b, Fig 2c or Fig 3 of the accompanying drawings.