Locks are continually being developed in order to increase the security they offer, and make them harder to defeat. Most improvements in prior art locking devices such as padlocks and mortise locks concentrate on making the locks larger, heavier, and stronger in order to resist the application of torque and other force, particularly in the case of padlocks.

According to the present invention there is provided a lock device having first and second members and a locking mechanism, wherein the first member is arranged to house the locking mechanism and wherein the second member is arranged to cover at least a portion of the locking mechanism, which locking mechanism is capable of occupying a locked position in which separation of the first and second members is resisted and wherein one of the first and second

members is freely rotatable with respect to the other member when the locked device is in the locked position.

In the locked position a rotatable portion can be provided to allow the second member to rotate freely about the first member. The rotatable portion can bear against a section of-the first-and second- members to engage the members in a locked position.

The locking mechanism should preferably be capable of occupying an unlocked position in which at least partial separation of the first and second members is permitted.

Typically, the locking mechanism includes a bearing such as one or more ball bearings that is moved from an unlocked position to a locked position in which it resists separation of the first and second members.

Typically, the rotatable portion rotates around the bearing (s) which also secures the two members together.

Typically, the first member is a body of the lock, and the locking mechanism comprises a tumbler rotatable within the body by means of a key. One end of the tumbler typically has on its circumference a recess for each bearing that receives and retains the bearing when the locking mechanism is inactive. In order to activate the

locking mechanism, the tumbler is turned, so that the bearings move out of the recesses in the tumbler and onto flats or shallower recesses circumferentially adjacent to the retaining recesses, moving radially outwards to straddle the shear line between the first and second members, thereby locking them together.

The tumbler is typically activated by a key and can be a conventional spring and pin design. In some embodiments the tumbler can have a sprung bearing system instead of pins. Once the matching key is inserted into the tumbler and activated, the profile of the activated key typically raises the sprung pins or bearings clear of the shear line between the tumbler and the body, so that the tumbler can rotate in order to rotate the end of the tumbler where the engagement bearings are recessed. The engagement bearings are held against rotation by recesses in the body of the lock, so that as the tumbler rotates and the bearings leave the recesses in the tumblers, they move radially rather than circumferentially.

In preferred embodiments of the invention, the tumbler has shallow recesses to receive and support the inner surfaces of the engagement bearings, and typically the engagement bearings can rotate in any direction within the shallow recesses. This means that the second member that is locked to the first member can rotate easily on the engagement bearings, which has the advantage that any torque that is

applied to the second portion is dissipated by the bearings.

According to another aspect of the invention, there is provided a lock device having a tumbler, wherein the tumbler has one or more tumbler bearings to lock the tumbler to the body of the lock. The tumbler can engage with the body of the lock device by means of tumbler bearings straddling the shear line between the tumbler and the body.

Although preferred embodiments of the present invention utilise engagement bearings for this purpose, in addition to locking the two portions together, some embodiments of the invention could be constructed by using a separate bearing to provide for free rotation of the second member relative to the first, without the need for engagement bearings.

The invention also provides a lock device having a tumbler, the tumbler being engaged with the body of the lock device by means of bearings straddling the shear line between the tumbler and the body.

The invention also provides a key and lock, wherein the lock has a tumbler device that is activated by a bearing device on the key. Typically, the tumbler device can be locked to the body of the lock by means of bearings that can be retained at the shear line between the tumbler and the body, and can be moved into the lock position by means of further bearings protruding from the key. In this

embodiment of the invention, the key can be switchable between an inactive configuration in which the bearings on the key are in a first configuration that does not cause the bearings between the tumbler and the body of the lock to move, and a second active configuration, in which they protrude from the key and cause the bearings between the tumbler and the body of the lock to move into a different configuration, thereby activating or de-activating the lock device.

According to another aspect of the invention, there is provided a lock device having first and second portions that are locked together by a locking mechanism, one of the portions comprising a rounded device.

Preferred embodiments of the invention include dumbbell or padlock varieties, as well as mortise or handle locks.

Typically a key slot is provided in the second member of the lock and can be aligned with the keyway in the tumbler by free rotation of the first and second members relative to one another. Once the key slot is aligned with the keyway, the key can be inserted and the tumbler system activated to unlock the two members from one another. In preferred embodiments, the key slot on the first member can be provided with one or more bearings housed in recesses in the outer face of the second

member adjacent to the key slot, in order to kick off drills that are applied to the key slot.

Typically the engagement bearings are ball bearings, and are typically formed of hardened metal, such as hardened steel. Locks can be constructed according to the invention suitable for use with a hasp, typically-by providing the second rounded portion on the outer surface of the hasp.

Instead of using ball bearings to engage the first and second members together, embodiments of the invention could use roller bearings, or plain bearings. In one such example, curved locking segments can be displaced by the key and/or tumbler system from the tumbler into an annular recess in the second member, so that the second member can rotate on the expanded locking segments in the same way as described for the engagement bearing in the above described embodiments.

An embodiment of the present invention will now be described, by way of example, and with reference to the accompanying drawings, in which:- Fig. 1 is a side sectional view of a lock in a lock configuration; Fig. 2 is an end view of the Fig. 1 lock; Fig. 3 is a side sectional view of the Fig. 1 lock in an unlocked configuration;

Fig. 4 is a side sectional view of a key for the Fig. 1 lock shown in an active configuration; Fig. 5 shows the same Fig. 4 key in an inactive configuration; Figs. 6,7 and 8 are sectional views through the line A on Fig. 1, showing the lock in the locked position, the unlocked position with the key activated, and the unlocked position with the key and tumbler having been turned within the body of the lock; Fig. 9 is a sectional side view of a door lock covering a hasp; Fig. 10 is an end view of the second member of the Fig. 9 lock; Fig. 11 is a side sectional view of a second door lock covering a hasp; Fig. 12 is an end view of the corresponding second member; Fig. 13 is an end view of a further embodiment of a lock; Fig. 14 is a side sectional view of the Fig. 13 lock; and Fig. 15 is a sectional view through the line AA of Fig. 14.

Referring now to the drawings, Fig. 1 shows a dumbbell style of padlock for use with a chain etc.

The lock comprises a first body portion 1, having a bulbous end and a tubular shaft ls with a hollow bore lb. The hollow bore extends from one end of the first portion 1 to the other, and is plugged at

the bulbous end by a plug p. The plug p can be removed, and is provided with 0-rings to exclude water from the bore lb. The other end of the bore lb is widened to receive a tumbler 3 of a locking mechanism. The tumbler 3 has a blind ended bore 3b to receive a key 10 that is inserted through the bore 1b when the plug p is removed. The tumbler 3 also has an end section that is recessed at 3r to receive and support a number of ball bearings 4 (see Fig. 3) so that the bearings 4 are received within the shaft of the first portion 1 and covered by a cap 5. The tumbler 3 also has a corresponding number of flats 3f or shallow recesses (see Fig. 1) that also support the bearings 4 but which are circumferentially displaced on the tumbler with respect to the recesses 3r as shown in Fig. 1. The bearings 4 are retained within radial apertures in the shaft of the first portion 1, which resists movement of the bearings 4 in the apertures around the circumference of the shaft ls. These apertures are aligned with slightly smaller apertures in the cap 5, which retain the bearings 4 in the apertures on the shaft ls, while allowing them to protrude from the circumference of the shaft ls as shown in Fig. 1.

In order to operate the lock, the two portions 1, 2 are connected together and the key 10 is inserted into the bore 1b to rotate the tumbler 3 from the unlocked position shown in Fig. 3. In that position the balls 4 are retained within the deep recesses 3r on the tumbler. Upon rotation of the tumblers into

the locked configuration shown in Fig. 1, the ball bearings 4 are pushed radially outwards through the apertures in the shaft ls and the cap 5, so that they rest on the flats 3f of the tumbler. In that configuration, when the shaft ls of the first portion is in the bore 2b of the second portion, the ball bearings 4 are moved into recesses 2r in the bore 2b of the second portion, and straddle the shear line between the two portions 1,2 being supported against radial inward movement by the flats 3f of the tumbler 3, and against circumferential movement by the apertures through the shaft ls of the first portion. It should be noted that in this configuration, the second portion 2 is free to rotate on the bearings 4 around the axis of the bore lb, 2b, so that torque that is applied to the second portion 2 in order to try to break the lock, simply results in the second portion rotating relative to the first, and does not damage the locking mechanism, or allow the two portions to be separated from one another.

Since the second portion 2 is rounded, and is preferably in the shape of a sphere, there are no flat surfaces that provide positions for the attachment of tools such as wrenches etc, and no leverage points allowing crowbars etc to be applied between the first and second portions.

Turning now to the key 10 and the operation of the tumbler 3, the key has an outer tubular case 11 in which is received an inner activating spindle 12.

The inner spindle 12 can rotate on its axis within the outer case 11 within constraints defined by a pin lip on the outer case that engages a slot 12s in the spindle. The outer case 11 is dimensioned to be received within the bore 1b of the first portion, and is long enough for the end of the key 10 to be received within the bore 3b of the tumbler 3.

At the other end of the key 10, the outer case 11 is apertured radially to receive three key-activating ball bearings 14. The inner spindle 12 has recesses 12r that are aligned with the apertures in the outer portion 11, to receive and support the bearings 14.

Rotation of the inner spindle 12 within the outer case 11 pushes the recesses 12r out of alignment with the bearings 14, so that the bearings 14 rise up within the apertures through the outer portion 11 and move from the inactive position shown in Fig. 5, to the active position shown in Fig. 4, where the bearings 14 stand proud of the outer surface of the outer portion 11.

When the key 10 is inserted into the bore lb of the locked device, the bearings 14 align axially with apertures 3a in the bore of the tumbler 3. The key 10 is initially inserted in its inactive position as shown in Fig. 5, so that the bearing 14 is flush with the outer circumference of the outer case 11, in order to facilitate insertion.

When the two portions 1,2 are locked together with the engagement balls 4 pressed radially outwards into the recess 2r by the flat 3f and with the key inserted, then the locking device is as shown in Fig. 6. In the Fig. 6 configuration, the key 10 has not been activated, so the bearing 14 lies flush with the outer circumference of the outer case 11.

When the lock is to be unlocked, the bearing 14 is aligned axially with the aperture 3a in the tumbler 3 (an end-stop or a marker on the case 11 can be used for this) and the key is then rotated as a whole until the bearing 14 and the aperture 3a are rotationally aligned also. In the locked position shown in Fig. 6, the aperture 3a in the tumbler 3 is held in alignment with another aperture in the shaft ls, so that the tumbler 3 cannot turn within the shaft, and the engagement balls 4 are held locked in the recesses 2r/3f thereby preventing dislocation of the first and second portions of the lock. The tumbler 3 and shaft Is are maintained in this position by a tumbler bearing 6 that is located in apertures la and 3a, and straddles the shear line between the two, thereby preventing relative movement. The tumbler bearing 6 is held in place by a garter spring 7 located in a groove around the shaft Is.

In order to unlock the first and second portions 1, 2, the key is first placed in the position shown in Fig. 6 so that the bearings 14 and 6 are aligned with one another. Once in that position, the key is activated as shown in Fig. 7, by rotating the inner

spindle 12 relative to the outer case 11, and displacing the bearing 14 radially outwards from the aperture in the outer portion 11. This pushes the tumbler bearing 6 against the force of the garter spring 7 until it is clear of the shear line between the tumbler 3 and the shaft Is, thereby allowing the key 10 and tumbler 3 to rotate as shown in Fig. 8.

The key 10 and the tumbler 3 can then rotate together until the main engagement bearings 4 align with and drop into the deep recesses 3r in the end of the tumbler 3, which corresponds to the position shown in Fig. 8. At that point, the tumbler bearing 6 engages a small dimple 3d on the outer surface of the tumbler to give a positive feel to the unlocked position. Since the engagement bearings 4 are located in the deep recesses 3r, they are flush with the outer surface of the shaft Is, which can then be withdrawn from the bore 2b of the second portion 2.

The key can then be de-activated by turning the inner bar 12 so that the bearing 14 drops back within the profile of the outer portion 11, and the key can be withdrawn from the bore lb if desired.

A single tumbler bearing 6 activated by a single bearing 14 could be sufficient for some simple embodiments of the invention, but in the preferred embodiments shown here, three separate tumbler bearings 6 restrained by three separate garter springs 7 are simultaneously displaced by a respective key bearing 14. One advantage of using the bearing tumbler system described herein is that the number of tumbler bearings and their respective

key bearings can be varied in accordance with the available space on the key, and the length of the tumbler. Likewise, the axial spacing between the bearings, and their circumferential position relative to one another on the tumbler can also be varied, so that extremely complex keys with many different tumbler bearings and with very different positions required for the corresponding key bearing can be constructed with relative simplicity, making the tumbler bearing design extremely difficult to defeat by picking. In addition, the key 10 will only de-activate the locking system in this embodiment when inserted into the bore in a particular rotational position such that the bearings 14 are aligned with the apertures 3a and la on the body of the lock, so even if a thief were provided with the key, it would not immediately enable them to open the lock without knowledge of which rotational position (see Fig. 2) the key required in order to open the locking mechanism.

Referring now to Fig. 10, a further embodiment of a lock according to the invention is described for use on a garage or shed door etc having a locking hasp h. In this construction, the lock device has a first portion 101 in the form of a body passing through the door d and secured at the inner surface by means of screws etc. The hasp h is then passed over the protruding shaft 101s, and the second portion 102 is then secured over the same shaft, preventing removal of the hasp h. The shaft 101s houses a conventional pin and spring tumbler system

activated by a conventional key as shown in the drawings. Insertion of the correct key displaces the pin tumblers to different extents against the forces of the respective springs until the split in the pins is aligned with the shear line between the tumbler 103 and the shaft 101s thereby permitting the tumbler 103 to turn relative to the shaft 101s, and align the engagement balls 104 with their respective recesses 102r. The arrangement of bearings 104 and recesses 102r is similar to that described for the previous embodiments. In the Fig.

9 embodiment, the hasp h conceals the inner edge of the bore 102b, thereby preventing any leverage from being applied on the inner lip of the bore 102b in order to separate the first and second portions 101, 102. As before, the second portion is rounded, and when the engagement balls 104 are displaced into the recesses 102r, so that they straddle the shear line between the first and second portions 101,102, then the second portion 102 can rotate freely relative to the first portion. Thus, any torque applied to the second portion in order to try and twist it from the first portion 101 is ineffective.

The end face of the second portion 102 has a key slot 102k which can be aligned with the keyway of the tumbler 103 by simply rotating the second portion 102 until the two are aligned. The key can then be inserted into the keyway by means of the key slot 102k. On either side of the key slot 102k, caged bearings are provided in the outer surface of

the second portion 102 in order to kick off any drills that are applied to the key slot 102k.

Referring now to Fig. 11 and Fig. 12, a modified lock device similar to that shown in Figs. 9 and 10 also has a rounded second portion 202 and a first portion with a shaft 201, and a tumbler 203. This embodiment operates in an identical manner to the Fig. 9 and 10 embodiment, except that the shaft of the first portion 201 does not extend through the door, but is instead connected thereto via bolts extending through a flange of the first portion.

The bolts and optionally the flange as a whole are covered by a hasp h when the lock is assembled and the first and second portions are locked together, so as to prevent attack by means of the bolts.

Turning now to Figs. 13,14 and 15, a further embodiment is described having a first portion 301 connected to a second portion 302. The end of the first portion houses a tumbler 303 as previously described, and is operated via a key inserted through a slot in a similar manner to the embodiments shown in Figs. 9 to 12. The other end of the first portion 301 can be formed in a manner similar to any previous embodiment herein described.

Instead of rotating on ball bearings 4,104, 204, the second portion 302 of the present embodiment is retained on the first portion by semi-circular locking segments 304 each having a rounded outer edge to fit within an annular recess on the second

portion 302. The second portion 302 can rotate on the locking segments 304 in a similar manner to the rotation of the second portion of the previous embodiments on the engagement bearings, 4,104, 204.

Optionally, the semi-circular locking segments 304 can incorporate an additional bearing race or an O- ring in their radially outward face in order to bear against the inside surface of the recess 302r.

The locking segments 304 are initially set flush with the outer surface of the shaft 301s of the first portion, in the configuration shown in Fig.

15, ie in the unlocked position. When the key is inserted into the slot 302k, and the second portion 302 rotated so that the key can then slide into the keyway of the tumbler 303, the rotation of the tumbler displaces the tumbler balls 306 radially outwards as previously described with reference to the tumbler bearings in the other embodiments, thereby pushing the locking segments 304 radially outwards into the position shown in Figs. 13 and 14, so that they resist removal of the second portion 302 from the first portion 301. More than one tumbler bearing can be used per locking segment and more than two locking segments can be provided.

Modifications and improvements can be incorporated without departing from the scope of the invention.

Clearly the present embodiment shown in Figs. 13 to 15 can be used with the pin tumbler of Figs. 9 to 12, or the bearing tumbler system described for the

earlier embodiments. 0-rings can mask the bore of the first and/or the second portions in order to resist intrusion of water into the locking mechanism.