EP1997982A1

EP1997982A1 - Locking device

Info

Publication number: EP1997982A1
Application number: EP08251916A
Authority: EP
Inventors: Nigel Philip Shenton
Original assignee: Window Fabrication and Fixing Supplies Ltd
Current assignee: Window Fabrication and Fixing Supplies Ltd
Priority date: 2007-05-31
Filing date: 2008-06-02
Publication date: 2008-12-03
Also published as: GB0710341D0

Abstract

A lock (1) adapted to prevent forcing of the lock, by bumping the lock, said lock (1) including a key hole (5) to allow insertion of a key (8) to operate the lock, a barrel (3) including a number of bores (9), a casing (2) including a number of corresponding bores (6) to the bores (9) in the barrel (3), and a number of locking pins (10) located in said bores (6) of the casing and the barrel to prevent rotation of the barrel with respect the casing unless the locking pins are correctly aligned in the bores (6,9). Each locking pin has at least two component parts (10,12) so that when the key (8) to operate the lock is inserted in the keyhole the locking pins (9) are depressed and aligned so that the barrel (3) can be rotated with respect to the casing (2) wherein at least one of the locking pins (9) has a component part (10) located in the casing when the lock is capable of being operated that is split into two or more members (11a, 11b).

Description

This invention relates to a locking device for a closure member such as a door, and in particular, to a locking device which is adapted to prevent forced entry by bumping the lock.
Over recent times the prevalence of so called "bumping" of locks to gain illegal entry to a premises has increased. Bumping of a lock involves forcing a lock using a key having a number of points corresponding to the number of pins in the lock. This is referred to as a "Bump Key". In use the bump key is inserted into the lock, and although the key will not make the lock operational, it provides a bridge between the person trying to bump the lock and the locking pins.
Now as a steady, but gentle, turning pressure is applied via the key, the key is tapped (bumped) so as to cause a relatively small impact force which is transmitted through the lock body to the pins therein. During this phase the locking pins are forced to spring by the force of the bump. If the amount of torque applied to the key is carefully controlled whilst the locking pins are bumped in this manner, the pins can become caught in the correct alignment at the barrel interface to allow turning of the lock barrel relative to its casing. As a consequence, with the steady sideward pressure of the key the lock is caused operate, so enabling illegal entry into premises.
It should be noted that the impact force applied during bumping of a lock is different to the larger forces which may be applied in an effort to break the lock.
The present invention is concerned with providing a means by which the successful bumping of locks can be prevented or at least alleviated.
In accordance with the present invention there is provided a lock adapted to prevent forcing of the lock, by for example bumping the lock, said lock including a key hole to allow insertion of a key to operate the lock, a barrel including a number of bores, a casing including a number of corresponding bores to the bores in the barrel, and a number of locking pins located in said bores of the casing and the barrel to prevent rotation of the barrel with respect the casing unless the locking pins are correctly aligned in the bores wherein each locking pin has at least two component parts so that when the key to operate the lock is inserted in the keyhole the locking pins are depressed and aligned so that the barrel can be rotated with respect to the casing wherein at least one of the locking pins has a component part located in the casing when the lock is capable of being operated that is split into two or more members. According to a second aspect of the present invention, there is provided the use of a lock according to the first aspect for preventing bumping of the lock.
In conventional locks the locking pin arrangement also includes a spring member located in the base of the bore of the casing which exerts an upward force on the locking pin arrangement forcing the respective pin members into their normal operational position, so locking the lock, and preventing relative rotation of the barrel and the casing. The basis of the normal operation of the lock of the present invention may be substantially unaffected by the adaptation that has been made to the lock according to the present invention and therefore said invention may also include one or more spring members located to act between the bottom of the bore in the casing and the bottom of the locking pin arrangement located in said bore.
In a preferred embodiment of the present invention the locking pins are formed as two components, an upper and a lower component, with the division between said components being aligned with the division between the barrel and the casing to allow the lock to be operated by insertion of the key in the keyhole. In a preferred arrangement of the present invention at least one of the upper components of the locking pins is split into two members.
With this configuration of the present invention when someone is trying to "bump" the lock the sideward pressure applied via the key, even though gentle, is sufficient to hold the lower member of the upper component of the locking pin in place between the barrel and the casing and this prevents operation of the lock.
With the present invention at least one of the locking pins has the upper component of the locking pin split into two members. The different construction of the locking pin causes the pin components to behave differently to a single component when bumbed, and it is this variation in the behaviour that allows the invention to work. In particular, the action and reaction forces between the adjacent pin components act differently upon application of an impact thereto than a single component. The outcome of the collision between pin components within the bore is thus far less predictable than for a single pin body.
The invention may prevent successful bumping of the lock in a satisfactory manner where only one locking pin from a number of locking pins is provided in the form of a plurality of component parts. This alone may provide the necessary added security. However a plurality of pins may provided in the form of a plurality of component parts according to a further embodiment. In this regard, the location of the adapted locking pin or pins along the number of locking pins is substantially immaterial. It is believed that the actual position of the adapted locking pin will also have an effect on the security of the lock and therefore the position.
Further, it is believed that increased security is provided by having at least two locking pins with an upper component split into a number of components, for example, two components. It is also believed that the number of locking pins that are adapted will have an effect on the characteristics of the lock.
Consequently the invention can be further heightened in effect by having the number and position of the adapted locking pins changed and located at random positions.
It is believed that it is the combination of different locking pin constructions and its effect on the characteristics of the pins under impact that provides the invention the ability to work.
According to a further embodiment, the inertia or movement characteristics of one or more pins or components parts of said pin or pins may be further altered from that of a solid pin body. In one embodiment, the shape of the pin body may be non cylindrical and may be substantially I-sbaped in section. The spring tensions and or spring properties may be varied between one or more bores. One or more pins or pin portions may be formed of a material having different characteristics to those of the other pins or pin portions, such as for example a different density. One or more pins or pin portions may be formed of a different material to the material of the other pins or pin portions. One or more pins or pin portions may be formed of a plastic, metal or ceramic.
Additionally or alternatively, lubricating fluid may be used to unbalance the movement characteristics of the pins in one or more bores. It is possible that a substantially uniform fluid composition may provide different theological properties once applied and thus may affect the reaction of one or more pins or pin elements differently to the others within the lock
The invention will now be illustrated by way of description of an example made in accordance with the present invention and as shown in the attached drawings:

Figure 1 shows a side view of a lock made in accordance with the present invention; and
Figure 2 shows an enlarged view of the locking pins of the lock shown in Figure 1.

The invention will now be described with reference to an example as shown in the drawings. There is shown a lock 1 having a casing 2, a barrel 3 and a series of locking pins 4, labelled A to E.
The casing 2 comprises a body having a main body of generally Keyhole shape which has a main bore 5 in the upper section of the body and a first series of five bores 6 extending into the lower section of the body and which bores 6 are arranged in alignment along the length of the main bore 5.
The barrel 3 is formed with an elongate circular body and includes a keyhole opening 7 at one end for the insertion of a key 8 to operate the lock and a series of five bores 9 in alignment along the length of the barrel 3. The bores 6 of the casing and the bores
9 of the barrel when the barrel is assembled into the main bore 5 of the casing are in alignment forming five counter bores.
Identifying the counter bores A to E from the key insertion end of the barrel 2 and casing 3 means that in the particular example shown each of the counter bores A, ad C to E is provided with a locking pin arrangement 10. The locking pin arrangement 10 comprises an upper pin member 11 and a lower pin member 12 which are located one above the other in the respective counter bore.
The locking pin arragement 10A of the counter bore B of the locking arrangement differs from that of the other locking pin arrangements 10 in that the upper member is further split into two components 11a and 11b forming a three member locking pin. In all other operational features the locking pin arrangement 10A is the same as for the other locking pin arrangements.
A spring member 13 is located in the bottom of each of the bores 6 so that it acts against the base of the lower pin member 12 urging the respective locking pin into a normal operational condition that has each of the locking pins 10 extending into the respective bore 9 of the barrel 3 so securing the barrel 3 and the casing 2 against respective rotational movement
The general operation of the locking pins in the lock is as with a conventional lock and the description thereof is incorporated in this application by way of reference.
Now in the normal condition without a key inserted in the lock the locking pin arrangements 10, 10A act to secure the barrel 3 and the casing in position with respect to each other. The pins extend across the interface between the barrel and the casing so as to prevent relative rotation therebetween and operation of the lock is prevented. The lock is secure in such a state.
When the correct key is inserted in to the keyhole 7 the indentations on the base of the key 8 engage the upper surfaces of the upper locking pin members 12 forcing the pins down in the boxes and compressing the spring member 13. The key 8 when fully inserted depresses the locking pins so that the separation between the upper and lower pin members is aligned with the interface or line of separation between the barrel 2 and the casing 2. The casing 2 and the barrel are now capable of being rotated with respect to each other.
Whenever a new lock type is developed there are always people seeking ways to open the lock without the key. One way in which the above type of lock can be opened without a key is a process referred to as "bumping", described above. Whilst this allows a lock smith to open a locked a door to allow someone access to their home it is also well known now and is used by thieves to enter homes for the purpose of theft.
All that the thief has to have is a set of "bump keys" (a standard key usable on locks of a type and make, cut to the number and position of the locking pins in the lock) and these are all to readily supplied by locksmiths for a small price. The problem of "bumping" has risen to the level that it is now a serious problem.
The present invention and in particular the locking pin arrangement 10A is adapted to provide a means for overcoming the problem. When a lock is bumped the pin members of the locking pin arrangements are jumped and the gentle but insistent pressure applied by the bump key allows the barrel and casing to move relative to one another when the upper pin members 11 clear the separation point between the casing and the barrel. This in turn allows the lock to be bumped clear and operated.
With the arrangement of the present invention the provision of the split upper pin member 11 in one of the bores means that the timing of this bumping and the effect on the locking pins is altered so that when the lock is bumped the lower part 11b of the upper pin member is trapped between the casing 2 and the barrel 3. This prevents the lock being operated.
The likelihood of the two pin components 11a and 11b rising above the dividing line between the barrel and casing upon application of an impact or "bump" to the lock is significantly reduced due to the interaction between the components 11a and 11b.
Upon application of an impact, the individual components will either collide or else move apart dependent the precise nature of the impact force and minutia such as the alignment of the components and instantaneous frictional forces. In the event that the pin components collide, the resultant reaction force will urge the pins in opposite directions such that a space is formed therebetween. Thus the pins components are extremely unlikely to move in unison to a position in which they are immediately adjacent one another and located above the split between the barrel and casing.
Whilst the likelihood of bumping being successful cannot be completely eradicated, the likelihood of success is significantly reduced when using standard bump keys to such an extent that it is ahnost impossible to achieve.
In order to further enhance the beneficial effects of the present invention, it has been found that the balance of the pins within the lock can be upset by further measures. In one example, one or more pin components can be formed as an anti-pick pin, such that it has a non-uniform cross sectional profile.
The anti-pick pin component may have opposing end portions of a first width or diameter and a mid portion of reduced width or diameter such that the pin component is '1' shaped in section. This removes weight from the pin component such that the inertia and movement characteristics of the pin component are altered. Thus when a solid pin components collides with a reduced weight pin component, the two pin components are even less likely to move in unison.
In such an anti-pick pin or any other form of pin component, the weight of the pin may be offset, for example by moving the central portion of the I section pin off centre. Again this may upset the natural balance of the pin and reduce the likelihood of successful bumping of the lock.
Additionally or alternatively, one of the upper pin components 11a or 11b could be formed of a different material to that of the other of the upper pin components. Metals of different densities or other material properties could be used, such as, for example, a combination of aluminium and steel pin components. One pin portion could be formed of a plastic material such that its weight and/or frictional properties within the bore are altered compared to the other pin portion.
Another option for upsetting the balance of the pins is to use springs having different spring characteristics or else similar springs which are compressed by varying amounts in each cylinder. This may be used in addition to or else instead of the above options.

Claims

The use of a lock for preventing forcing of the lock by bumping, said lock comprising:
a barrel including a number of bores,

a casing including a number of corresponding bores to the bores in the barrel, and,

a number of locking pins located in said bores of the casing and the barrel to prevent rotation of the barrel with respect the casing unless the locking pins are in an aligned condition within the bores

wherein each locking pin has at least two component parts such that the locking pins can be depressed upon insertion of a corresponding key into the lock and the component parts of said pins aligned so that the barrel can be rotated with respect to the casing,

and wherein at least one of the locking pins has a component part arranged to be located in the casing when in said aligned condition, said pin component being split into two members such that the two members tend to move out of said aligned condition required for operation of the look upon application of a bumping force thereto.
A lock as claimed in claim 1, wherein the lock also comprises one or more spring members located to act between the bottom of the bore in the casing and the bottom of the locking pin arrangement located in said bore which urge the locking pin arrangements into a position where the lock is locked.
A lock as claimed in claim 1 or claim 2, wherein the locking pins comprise two components, an upper and a lower component with the division between said components being aligned with the division between the barrel and the casing to allow the look to be operated by insertion of a suitably shaped key in the keyhole during normal operation and at least one of the upper components of the locking pins is split into two members.
A lock as claimed in any preceding claim, wherein the two members have different material properties.
A lock as claimed in any preceding claim, wherein the two members have different densities.
A lock as claimed in any preceding claim, wherein the two members are formed of different materials.
A lock as claimed in any preceding claim, wherein the two members have different sectional profiles.
A lock as claimed in claim 2, wherein at least one of the spring members is arranged to provide a different force to the pin arrangement in the corresponding bore than the force applied by another spring member to another pin arrangement.
A lock adapted to prevent forcing of the lock, by for example bumping the lock, said lock including a key hole to allow insertion of a key to operate the lock, a barrel including a number of bores, a casing including a number of corresponding bores to the bores in the barrel, and a number of locking pins located in said bores of the casing and the barrel to prevent rotation of the barrel with respect the casing unless the locking pins are correctly aligned in the bores wherein each locking pin has at least two component parts so that when the key to operate the lock is inserted in the keyhole the locking pins are depressed and aligned so that the barrel can be rotated with respect to the casing wherein at least one of the locking pins has a component part located in the casing when the lock is capable of being operated that is split into two members.
A lock adapted to prevent forcing of the lock, by for example bumping the lock, said lock comprising a barrel including a number of bores, a casing including a number of corresponding bores to the bores in the barrel, and a number of locking pins located in said bores of the casing and the barrel to prevent rotation of the barrel relative to the casing unless the locking pins are correctly aligned in the bores, wherein each locking pin has at least two component parts so that when the key to operate the lock is inserted in the keyhole the locking pins are depressed and aligned with respect to the interface between the barrel and casing so that the barrel can be rotated with respect to the casing and wherein at least one of the locking pins has a first component part having different material properties to a second component part.