Locking device

Abstract: A locking device, comprising a housing (20) having a first opening (25) and a second opening (26), the first opening (25) communicating with a channel (9) in the housing; an insertable member (21) having first and second arms which are rigidly joined to one another, the first arm being adapted to be slidingly insertable through the first opening (25) and into the channel (9) and the second arm being simultaneously slidingly insertable through the second opening (26); and a disposable locking element (42) adapted to lockably engage with the insertable member (21) and/or the housing (20) when the insertable member (21) has been inserted in the housing (20), whereupon breakage of part of the disposable locking element (42) permits disengagement thereof from the insertable member (21) and/or from the housing (20).

Description: This invention relates to a locking device. A particular application for such a locking device is as a security seal for use on passenger aircraft. The device can be used to seal the containers used for the in-flight distribution of perishable and non-perishable goods. The theft of goods from containers costs airlines vast sums of money each year. Although containers are sealed when they leave the warehouse, it is necessary for the seals to be easily removable by hand as it is quite impractical for cabin crews to carry special seal removal tools on the aircraft. We have found that these problems can be solved by a locking device which is pressure-sensitive, the device thus being actuated by the reduced pressure during flight. However, the invention does not concern a pressure-sensitive locking device. DE-C-341824 discloses a keyless padlock with a hasp 12. A locking element 15 is inserted from the side, through an aperture in the padlock housing and through holes in the arms of the hasp. The inner end of the locking member engages behind a catch 4, which can rotate against the action of spring 5. To unlock the padlock, the head 16 of the member 15 is sheared off, and then the remainder of the member is pushed out (using some sort of tool) through the opposite side of the housing. GB-A-2064638 discloses a padlock with a key, but access to the key hole can be blocked by cover which is locked by a breakable seal. The present invention provides a locking device comprising: a housing having a first opening and a second opening, the first opening communicating with a channel in the housing; a rigid insertable member having first and second arms which lie in a common plane and which are rigidly joined to one another, the first arm having an aperture and said first arm being adapted to be slidingly insertable lengthwise through the first opening and into the channel, the second arm being simultaneously slidingly insertable lengthwise through the second opening, and the housing having an aperture which registers with the aperture of the first arm when the insertable member is inserted into the housing; and a disposable locking element adapted to lockably engage with the first arm of the insertable member and the housing when the first arm has been inserted in the channel, an insertion portion of the disposable locking element engaging in said apertures of the housing and the first arm, the disposable locking element being breakable by release of the insertable member from the housing; characterised in that: the aperture of said first arm extends therethrough substantially perpendicular to said common plane whereby in use the disposable locking element is pushed onto the housing in a direction substantially perpendicular to said common plane, part of the disposable locking element being breakable by manual manipulation thereby to permit disengagement thereof from the insertable member. The locking device can serve both as a barrier seal and as an indicative seal. The insertable member is shaped so as to engage with a hasp or other securing device of an aircraft goods container. The insertable member can be U or J-shaped whereby the. limbs can be inserted in two channels in the housing and lockable in one or both such channels, the device then being usable in the same way as a padlock. The locking device includes an additional disposable locking element which engages with the elongate member in the locked position, and which has to be physically broken to permit withdrawal of the elongate member from the channel. Reference is now made to the accompanying drawings, in which: Figure 1 is an exploded perspective view of a locking device according to an embodiment of the invention; Figure 2 is an end view of the disposable locking element used in the embodiment; Figure 3 is a plan view of the embodiment when ready to be locked; and Figure 4 is a plan view of the embodiment in the locked position, and partly cutaway to show internal details. Referring now to Figures 1 to 4 an embodiment of the invention is described. The locking device shown includes a housing 20, an insertable member in the form of a flat bar 21 and a disposable locking element 22. The housing has a hinged guide member 23, pivoted to an end portion 24 of the housing. The guide member 23 is able to pivot between an open position (Figure 3) and a closed position (Figure 4). The guide member 23 has an opening 25 for receiving the bar 21, and in the closed position the opening 25, which extends through the guide member, is in register with openings at opposing ends of the main body of the housing 20, so as to effectively form a channel through the housing. The bar 21 is J-shaped. An end portion of the longer limb can be pre-placed in the opening 25 of the guide member 23, with the guide member in the open position as shown in Figure 3. In order to effect locking, as described in more detail below, the guide member 23 is then rotated to the closed position (Figure 4) and the longer limb of the bar 21 is then fully inserted in the channel of the housing 20, the end portion of the longer limb projecting slightly from the other side of the housing (Figure 4). The shorter limb of the bar 21 is received in an opening 26 in a side wall of the housing, and in the locked position travels to a short extent through the opening into the interior of the housing (Figure 4). The fit of the end of the longer limb of the bar 21 in the opening 25 is sufficiently close that the bar 21 can be held by the guide member 23, as shown in Figure 3, but does not impede further insertion of the bar 21 through the opening 25 until the bar reaches the locked position, as shown in Figure 4. The locking device includes a supplementary security seal in the form of a disposable locking element 22 (Figures 1 and 2). The disposable locking element 22 includes a head part 42 in the form of a flat tab, and upstanding on one side thereof a plug part 43 and a locking post 44. The disposable locking element 22 cooperates with the guide member 23 (which is part of the housing 20) and the bar 21 in the following manner. The bar 21 has a circular hole 45 in its longer limb spaced from the trailing end (on insertion) of the slot 38. The guide member 23 has a corresponding through hole 46 whereby, when the bar 21 is locked in the housing 20, the holes 45 and 46 are in register and can receive the locking post 44 of the disposable locking element 22. The guide member 23 has a hollow interior, with an opening 47 spaced to one side of the hole 46. The plug part 43 of the disposable locking element is in the form of a resilient barb. The plug part 43 passes through the opening 47 as the locking post 44 is inserted through the holes 46 and 45. As the plug part 43 passes through the opening 47, the barb is resiliently deflected to one side, but as soon as it is inside the guide member 23, the barb resiliently returns to its original dimensions, and resists withdrawal. In this position, the bar 21 is locked by the locking post 44. Thus, the disposable locking element 22 must be released in order to withdraw the bar 21. The head part 42 incorporates a tear line which separates the parts of the head part respectively attached to the plug part 43 and the locking post 44. Thus, by manual manipulation, which is assisted by a pull tab 48, the disposable locking element can be split into two parts. The locking post 44 can then be freely withdrawn, permitting release of the bar 21. The plug part 43 remains inside the guide member 23 but the guide member 23 can now be freely rotated to the open position, thereby releasing the plug part. The disposable locking element 22 can be marked for security purposes, such as with a serial number or bar code. If desired, the locking device can be relocked using a new disposable locking element. It is sometimes desirable for containers on aircraft to be openable while the aircraft is still on the ground, for example if there is a flight delay. This can be accommodated according to the present invention as the device is only locked by the disposable locking element 22. In a typical situation, a limited number of containers of the aircraft would be locked in this way, the remaining containers being locked in a full pressure-sensitive manner. A container on an aircraft may be locked by the device according to the invention by cooperation between the bar 21 and a hasp or other securing device on the container. Alternatively, a cable may be provided with loops at its end. The cable is then used to secure a container door in the closed position and the loops are held by the bar 21 which acts in the manner of a padlock.

Claims: A locking device comprising: a housing (20) having a first opening (25) and a second opening (26), the first opening communicating with a channel in the housing; a rigid insertable member (21) having first and second arms which lie in a common plane and which are rigidly joined to one another, the first arm having an aperture (45) and said first arm being adapted to be slidingly insertable lengthwise through the first opening (25) and into the channel, the second arm being simultaneously slidingly insertable lengthwise through the second opening (26), and the housing having an aperture (46) which registers with the aperture of the first arm when the insertable member (21) is inserted into the housing; and a disposable locking element (22) adapted to lockably engage with the first arm of the insertable member (21) and the housing (20) when the first arm has been inserted in the channel, an insertion portion (44) of the disposable locking element engaging in said apertures (45, 46) of the housing and the first arm, the disposable locking element being breakable by release of the insertable member from the housing; characterised in that : the aperture (45) of said first arm extends therethrough substantially perpendicular to said common plane whereby in use the disposable locking element (22) is pushed onto the housing (20) in a direction substantially perpendicular to said common plane, part of the disposable locking element (22) being breakable by manual manipulation thereby to permit disengagement thereof from the insertable member (21). A locking device as claimed in claim 1, in which the disposable locking element is of plastics material and includes a head part (42) and a plug part (43), the plug part being resiliently deformable so as to permit engagement with but resist disengagement from the housing (20) and/or the insertable member (21), and the head part (42) including a tear line whereby manual manipulation of the head part will permit separation thereof from the plug part (43) with resultant disengagement from the housing and/or insertable member. A locking device as claimed in claim 2, in which the insertion position (44) of the disposable locking element comprises a locking post adjoining the head part (42), the plug part being engageable with the housing and the locking post being simultaneously engageable in the apertures of the housing and the insertable member, wherein the tear line separates respective parts of the head part adjoining the plug part and the locking post, whereby tearing along the tear line permits the locking post to be disengaged from the housing and from the insertable member. A locking device according to any preceding claim wherein the insertable member (21) is J or U-shaped. A locking device according to any preceding claim wherein the housing (20) includes a hinged guide member (23), the guide member (23) including the opening (25) for receiving one arm of the insertable member (21).

Inventors: CRISP DAVID JOHN, CRISP, DAVID JOHN
Applicants: ITW LTD, ITW LIMITED
Application year: 1997
Main classification: B64D17
IPC codes: E05B67, B64D11, B64D17, E05B39, E05B51