BACKGROUND OF INVENTION
1. Field of Invention
The present invention relates to a padlock and, more particularly, to a padlock including a shackle locked by key-operable locking mechanism at an end and locked by combination locking mechanism at another end so that the padlock can be unlocked by using a key or dialing the combination locking mechanism to an unlocking number.
2. Related Prior Art
To prevent belongings from missing, travelers usually lock their trunks, suitcases, briefcases, bags or the like. A combination lock is the most common lock installed in a trunk because it takes little space. Each traveler sets up an unlocking number for the combination lock. Thereby, others cannot unlock his trunk without knowing the unlocking number. However, terrorists may use trunks to deliver explosives. In airports, security personnel may have to check travelers' trunks without their presence. In some countries, travelers are required not to lock their trunks. The travelers may lose their belongings if leaving their trunks unlocked. If the travelers lock their trunks, the security personnel are authorized to break the trunks for security check. There is a dilemma between the travelers' rights and the flight safety. Therefore, there is a need for padlocks that can protect the travelers' belongings and allow the security personnel to unlock them.
SUMMARY OF INVENTION
It is therefore an objective of the present invention to provide a padlock that can be unlocked by an owner dialing an unlocking number or security personnel using a general key.
According to the present invention, a padlock includes a housing, a block, a shackle, a general locking mechanism and a private locking mechanism. The housing includes a first channel and a second channel therein. The block is partly disposed in the second channel of the housing. The block includes a receptacle therein. The shackle includes a long arm movably disposed in the first channel and a short arm for insertion in the receptacle of the block. The general locking mechanism is disposed in the housing for locking and unlocking the long arm of the shackle. The private locking mechanism is disposed in the housing for controlling the block so that the block can be engaged with and disengaged from the short arm of the shackle.
BRIEF DESCRIPTION OF DRAWINGS
The present invention will be described via the detailed illustration of embodiments referring to the drawings wherein:
FIG. 1 is a perspective view of a padlock according to an embodiment of the present invention;
FIG. 2 is a top view of the padlock shown in FIG. 1;
FIG. 3 is a cross-sectional view of the padlock shown in FIG. 1, showing a shackle locked;
FIG. 4 is an exploded view of a key-operable locking mechanism and a block of the padlock shown in FIG. 1;
FIG. 5 is another cross-sectional view of the padlock shown in FIG. 1, showing a long arm of the shackle released from a combination locking mechanism of the padlock;
FIG. 6 is another perspective view of the padlock shown in FIG. 1, showing that an engaging portion of the block is rotated to a position for releasing a short arm of the shackle; and
FIG. 7 is view similar to FIG. 6, showing that the short arm of the shackle is rotated off the engaging portion of the block; and
FIG. 8 is a cross-sectional view of the padlock shown in FIG. 7 and a key rotated in the key-operable locking mechanism of the padlock.
DETAILED DESCRIPTION OF EMBODIMENTS
With reference to FIGS. 1 through 8, a padlock according to an embodiment of the present invention includes a housing 70, a block 72, a shackle 71, a combination locking mechanism 9 and a key-operable locking mechanism 8.
As shown in FIG. 1, a space 703 is defined in a corner of the housing 70, and an outer wall 704 of the housing 70 faces the space 703. As shown in FIG. 3, the housing 70 further defines a first channel 701 and a second channel 702 in a top surface thereof.
The block 72 is movably disposed on the housing 70. As best seen in FIG. 4, the block 72 includes a mounting portion 721, an engaging portion 722 and a neck 720 connecting the mounting portion 721 and the engaging portion 722. Specifically, the mounting portion 721 of the block 72 is disposed inside the housing 70. The neck 720 of the block 72 is received in the second channel 702 of the housing 70. The engaging portion 722 of the block 72 is received in the space 703 of the housing 70. Moreover, the mounting portion 721 includes a pair of recesses 724 therein. The engaging portion 722 includes a receptacle 723 in a top and a gap 725 in a periphery and in communication with the receptacle 723. The diameter of the neck 720 is smaller than that of the mounting portion 721 and that of the mounting portion 722.
As shown in FIG. 3, the shackle 71 includes a long arm 711 partly received in the first channel 701 of the housing 70 and a short arm 712 extending from the long arm 711 and located outside the housing 70 for insertion in the receptacle 723 of the block 72. The long arm 711 of the shackle 71 is movable with respect to the housing 70 and includes a stop 714 at an end thereof. The size of the stop 714 is larger than that of an opening of the first channel 701 for preventing the long arm 711 from fully sliding off the first channel 701. The short arm 712 is rotatable about the longer arm 711 to or off a confining position. The diameter of the short arm 712 is smaller than the width of the gap 725 so that the short arm 712 can be moved through the gap 725.
As shown in FIGS. 1 through 3, the block 72 is located in a locking position and the short arm 712 of the shackle 71 is located in the confining position. At this time, the gap 725 of the block 72 is completely blocked by the wall 704 of the housing 70 and a distal end of the short arm 712 of the shackle 71 is enclosed by an inner wall of the block 726 and the wall 704 of the housing 70 so that the short arm 712 of the shackle 71 is restrained in the receptacle 723 of the block 72 and is not allowed to rotate off the confining position about the long arm 711 of the shackle 71. Preferably, the surfaces of the walls 726, 704 that together enclose the distal end of the short arm 712 are both arc surfaces, as best seen in FIGS. 2 and 7.
The combination locking mechanism 9 is disposed in the housing 70 for locking and unlocking the long arm 711 of the shackle 71. The combination locking mechanism 9 includes a stem 91 for engagement with the stop 714 of the long arm 711 of the shackle 71 and a plurality of numeral wheels 90 rotationally mounted on the stem 91 for locking and unlocking the long arm 711 of the shackle 71. When the combination locking mechanism 9 is dialed to an unlocking number, the stop 714 of the long arm 711 is released from the stem 91 and the long arm 711 is biased upwardly, as shown in FIG. 5, so that the short arm 712 is removed from the receptacle 723 of the engaging portion 722 of the block 72.
Referring back to FIG. 3, the key-operable locking mechanism 8 is disposed in the housing 70 for controlling rotation of the block 72 so that the block 72 can be engaged with and disengaged from the short arm 712 of the shackle 71. As best seen in FIG. 4, the key-operable locking mechanism 8 includes a body 80, a rotor 81 disposed in the body 80 and a driving rod 813 extended from the rotor 81. The rotor 81 includes a keyhole 811 therein for receiving a key 82. The driving rod 813 has an end formed with two plates 812 which are received in the respective recesses 724 of the mounting portion 721 of the block 72 so that the rotor 81 can be driven by the key 82 to rotate the block 72.
As mentioned above, the key 82 can rotate the rotor 81, which in turn will rotate the block 72 to an unlocking position. FIG. 6 illustrates that the block 72 is in the unlocking position and the short arm 712 of the shackle 71 is also located in the confining position. At this time, the gap 725 of the block 72 is not blocked by the wall 704 of the housing 70 and the distal end of the short arm 712 of the shackle 71 is no longer enclosed by the wall 726 of the block 72 and the wall 704 of the housing 70, and therefore the short arm 712 is free to rotate off the confining position about the long arm 711 and be removed from the receptacle 723 of the block 72 via the gap 725, as shown in FIG. 7 or 8.
The present invention has been described via the detailed illustration of the embodiment. Those skilled in the art can derive variations from the embodiment without departing from the scope of the present invention.
Therefore, the embodiment shall not limit the scope of the present invention defined in the claims.