Field of the Invention This invention concerns the protection of padlocks from actions intended to cause damage to the locks.

Background to the Invention The shackle of a padlock is a prime point for attacking the padlock in order to gain unauthorized access to the area or device locked by the padlock. Many devices have been proposed and used for the protection of the shackle of a padlock while the lock is in use. However all suffer from one or more disadvantages.

Many have either a hinged portion and this is a potential weaker area for forcible attack as well as being a cause of increased manufacturing cost. Many shackle protection devices must be affixed to the surfaces surrounding the lock area so the installation involves additional cost, and is in many cases inconvenient or damaging to the surrounds.

There is a need for an improved device for the purpose. An aim of the present invention is to provide a padlock protector and a method of protecting a padlock which overcomes these disadvantages.

Summary of the Invention Accordingly, in one aspect the invention provides a security cover for shielding the shackle of a padlock, said cover comprising: (a) two side plate portions linked by a top joining portion to form a U-shaped body portion; (b) a web portion extending from one side plate to the other side plate;

(c) said web portion and side plate portions defining two end cavity portions extending between the side plate portions and on respective opposite sides of the web portion, (d) said web portion separated from the top joining portion by a hole extending between said two end cavity portions; and (e) a slot, extending into said U-shaped body portion and into said web portion, said slot comprising a body-slot portion formed in said body portion and a web-slot portion formed in said web portion; and (f) portion of said hole laying between said body-slot portion and said web-slot portion.

The slot may extend fully through said top joining portion and extend only part way through each of said side plate portions. The slot may extend only part way through said web portion. The slot may extend into one of said side plate portions and at least substantially through said web portion.

One of said side plates may be relieved on its inner edge opposite said top joining portion to form a flange projecting away from said top joining portion. Each of said side plates may be relieved on its inner edge opposite said top joining portion to form a flange projecting away from said top joining portion.

The slot may extend fully through one of said side plate portions and fully through said web portion. The slot may extend only part way through the thickness of one of said side plate portions.

In another aspect, the invention provides a method of using a padlock, having a body portion and a U-shaped shackle portion, to lock a component so that the component or an adjacent associated element is restrained from moving, said method comprising placing said component within the slot of a security cover as defined above, feeding the free end of an unlocked shackle of the padlock through said hole in the security cover such that at least a portion of said component is held in the slot by the shackle,

and locking said free end of the shackle to the body of the padlock, whereby the shackle is held within said hole and said cavity portions.

One of said side plates may be relieved on its inner edge opposite said top joining portion to form a flange projecting away from said top joining portion, and said flange may extends to cover a part of one side of the body of the padlock.

Each of said side plates may be relieved on its inner edge opposite said top joining portion to form a flange projecting away from said top joining portion, and said flanges may extend to cover a part of both sides of the body of the padlock.

Brief Description of the Drawings In order that the invention may be more fully understood there will now be described, by way of example only, preferred embodiments and other elements of the invention with reference to the accompanying drawings where: Figure 1 is a perspective view of a padlock having a security cover and locking a pad-bolt in accordance with one embodiment of the invention; Figure 2 is a perspective view of a padlock having a security cover and locking a pad-bolt in accordance with another embodiment of the invention; Figure 3 is a front view of the security cover shown in Figure 1; Figure 4 is an end view of the security cover shown in Figure 3; Figure 5 is a view looking at the top of the security cover shown in Figure 3; Figure 6 is a view looking at the bottom of the security cover shown in Figure 3; Figure 7 is a perspective view looking from above the security cover shown in Figure 3; Figure 8 is a perspective view looking from below the security cover shown in Figure 3; Figure 9 is a rear view of the security cover shown in Figure 2; Figure 10 is a front view of the security cover shown in Figure 2; Figure 11 is an end view of the security cover shown in Figure 2; Figure 12 is a bottom view of the security cover shown in Figure 2;

Figure 13 is a front view of a security cover according to a further embodiment of the invention; Figure 14 is an end view of the security cover shown in Figure 13; Figure 15 is a view looking at the bottom of the security cover shown in Figure 13; and Figure 16 is a view looking at the top of the security cover shown in Figure 13.

Description of the Preferred Embodiment and Other Examples of the Invention Referring to Figures 1 and 3 to 8, a padbolt 2 is shown locked by a padlock 12 which is protected by a security cover 10 according to one embodiment of the invention.

The padbolt comprises a frame 3 and a sliding bolt 4 held captive within the frame.

The frame 3 has a base portion 5 which is fastened in use to a suitable surface where the locking function is required. Extending from the base 5 is a flange portion 6 which carries two holes 7, only one of which is visible in Figure 1. The structure and working of such padbolts are well known and will not be further described in this specification except as they relate to the fitment of the padlock and security cover.

The padlock 12 is of conventional form having a body portion 14 and a shackle portion 16. The shackle 16 has a U-shape with one end captive but rotatable within the body 14 and the other end free to move when unlocked and captive within the body 14 when locked.

The cover 10 has two side plate portions 18 and 19 which form side faces 22 and 23 of the cover. A top portion 26 extends for the full width of the cover except for a slot therethrough which is described in further detail below. The two side plate portions 18 and 19 and the top portion 26 together form a U-shaped body portion 30.

Extending between the side plates 18 and 19, from one side plate 18 to the other side plate 19, is a web portion 32 which lies centrally relative to the two end faces 34 and 35. The web 32 and side plate portions 18 and 19 define two end cavity portions

formed within the cover 10 and extending between the side plate portions 18 and 19 and on respective opposite sides of the web 32.

Where the web 32 would otherwise extend up to the top portion 26, a hole 40 is formed to extend between and connect the two end cavity portions 37 and 38.

The slot 28 extends into the U-shaped body portion 30 and into the web 32. The portion of the slot extending into the body portion 30 will be referred to as the body slot-portion 44, and the portion of the slot 28 formed in the web 32 will be referred to as the web slot-portion 46. The portion of the slot 28 formed in the top 26 of the body portion 30 will be referred to as the top slot-portion 45 and this forms part of the body slot-portion 44. The hole 40 lies intermediate of the body slot-portion 44 and the web slot-portion 46 such that the slot 28 could be considered as extending through the hole 40.

The slot 28 extends from side face 22 to side face 23. The slot 28 extends fully through the top face 27 and the top portion 26, but extends through each of the side plate portions 18 and 19 for only about the top two-thirds of their height. The slot 28 extends through only about the top two thirds of the web 32.

At the bottom faces 48 of the cover 10, each of the side plates 18 and 19 carries a relief 50 and 51 respectively on its inner edge 52 and 53 respectively. The relief 50 and 51 takes the form of a right angular relief such that respective flange portions 56 and 57 are formed on the bottom of each side plate 18 and 19. The outer face 60 and 61 of respective flanges 56 and 57 is co-planar with, continuous with, and forms part of side faces 22 and 23. In use, the flanges 56 and 57 cover the top portion 17 of the sides of the body of the padlock 12 and thus prevents for example a hacksaw blade being slid between the bottom of the cover 10 and the top of the body 14 of the padlock in order to attack the shackle 16 of the padlock 12.

In order to affix the padlock 12 with its security cover 10 to the pad bolt 2, the pad bolt is provided with two holes 7 through which the shackle 16 of the padlock may be

affixed. In Figure 1 the padlock shackle is through one of these holes (namely hole 7 which is hidden) while the other hole 8 is visible and not engaged.

In order to fit the padlock and its security cover to the pad bolt, the flange 6 is first slid into the slot 28 until the hole 7 is in line with the security cover's hole 40 and the free end of the padlock is pushed through the hole 40 and the hole 7 within it. The free end of the padlock is then pushed around the web 32 in a generally horizontal motion, the padlock is then swung down to its vertically hanging position, the shackle 16 rotating around the web 32 and then the body of the padlock is pushed upwards to lock the free end of the shackle 16 into the body 14 while at the same time pushing the cover 10 upwards so that the inside top of the shackle is very close to the top of the web 32. The inside of the curve of the shackle 16 is now close to the top of the web 32 so that there is insufficient vertical movement of the cover 10 relative to the padlock 12 for the flanges 56 and 57 to be raised sufficiently for someone to gain access to the shackle. The side arms of the shackle are visible through the end cavity portions 37 and 38 (which open out to the end faces 34 and 35) but any attack through the relatively narrow opening would be very difficult.

The preferred material of construction for cover 10 is an integral block of cast stainless steel so it has no joined or moving parts to wear or provide a weak point susceptible to malicious attack.

Referring now to Figures 2 and 9 to 12, the same pad bolt 2 described above is here fitted with a security cover 110 in accordance with another embodiment of the invention. In this embodiment, features of the cover 110 are identified in the Figures and description using numbers such that their last two digits correspond to the number used for equivalent features on cover 10.

In securing cover 110, the slot 128 which accommodates the flange 6 of the pad bolt extends through only one of the side plate portions 118, leaving the other side plate portion 119 slotted for about half its thickness. The slot 128 does not penetrate to the side face 123. The slot 128 thus has a body slot-portion 144 which extends through

the side plate portion 118 and the slot also has a web slot-portion 146 which extends through the web and into the side plate portion 119. The slot 128 has a top slot- portion 145, which is part of the body slot-portion 144, and which stops short of the top face 127. The slot 128 does not pass through the top face 127.

In this embodiment only one of the side plates, namely side plate portion 119, carries a flange 157 which in use extends down to cover the top portion of the side of the body of the padlock 12 in order to prevent a hacksaw blade being slid between the bottom of the cover 110 and the top of the body 14 of the padlock.

The cover 110 extends higher than the cover 10 shown in Figure 1 and thus provides greater protection for the pad bolt as well as for the padlock.

The cover 10 may be used when padlocking in situations different to those where cover 110 is usable. For example, the slot of cover 10 may be slid over the braking disc on a motorcycle and the shackle of the padlock passed through a hole in that disc in order to immobilize the motorcycle while providing protection for the shackle of the padlock. Alternatively, the slot of cover 10 may be pushed over an available wire or rod component before fastening the padlock in order to securely fasten the padlock and cover to said wire or rod.

The security cover 210 shown in Figures 13 to 16 is the most preferred configuration of security covers the subject of the present invention. The cover 210 is very similar in construction to cover 10 shown in Figures 3 to 8. Features of the cover 210 are identified in the Figures and description using numbers such that their last two digits correspond to the number used for equivalent features on cover 10.

The most significant difference between cover 210 and cover 10 is that the hole 240 is enlarged radially when compared with the hole 40 in the first-described embodiment.

Hole 40 has a vertically elongated oval shape best seen in end view Figure 4. But hole 240 has a circular cross section of considerably larger diameter as best seen in end view Figure 14. The hole 240 therefore encroaches into the side plates 218 and

219. Thus, each of the side plates 218 and 219 is thinned at the hole 240, so forming narrowed necks 220 and 221 in the side plates 218 and 219 respectively between the hole 240 and the side faces 222 and 223. Accordingly the maximum distance between the side plates 218 and 219 within the hole 240 is the diameter of the hole which is shown as dimension"d"in Figures 14 and 16. That distance"d"is greater than the distance between the side plates 218 and 219, which is shown as dimension "t"on Figures 14 and 16. Dimension"t"is the distance between the side plates 218 and 219 measured within those portions of the end cavity portions 237 and 238 which are separated by, but alongside, the web portion 232.

The hole 240 can be seen as straight cylindrical bore extending from one end face 234 to the other end face 235, which end faces are at opposite ends of the cover 210.

A benefit of having the hole 240 enlarged in this manner is that the cover 210 is better able to fit pad bolts having a variety of sizes and positioning of their holes 7 on the flange 6. The parallel inside walls 260 and 261 of the end cavity portions 237 and 238 restrain the shackle of the padlock more snugly than if those walls were more widely spaced, but the expanded size of the hole 240 accommodates a greater range of sizes of pad bolt without increasing the distance"t"between the opposing walls 237 and 238 of the end cavity portions.

The U-shaped body portion 230, web portion 232, and reliefs 250 and 251 at the bottom faces 248 are substantially the same as the corresponding features in the previously described security cover 10 shown in Figures 3 to 8.

Whilst the above description includes the preferred embodiments of the invention, it is to be understood that many variations, alterations, modifications and/or additions may be introduced into the constructions and arrangements of parts previously described without departing from the essential features or the spirit or ambit of the invention.

For example, the preferred security covers described are made from cast stainless steel. However they could otherwise be made from cast aluminium, any other suitable metal, or even an engineering grade plasic such as a fibre reinforced plastic.

Also although the preferred security covers are formed as a single integral casting, they could be fabricated from components. A particularly useful example may be the cover 10 shown in Figures 3 to 8 which has two planes of symmetry and thus a manufacturer may wish to make two identical castings which are then affixed face to face by welding, gluing or any other means. This would provide a manufacturer with an alternative fabrication option.

It will be also understood that where the word"comprise", and variations such as "comprises"and"comprising", are used in this specification, unless the context requires otherwise such use is intended to imply the inclusion of a stated feature or features but is not to be taken as excluding the presence of other feature or features.

The reference to any prior art in this specification is not, and should not be taken as, an acknowledgment or any form of suggestion that such prior art forms part of the common general knowledge in Australia.