1. Field of Invention
The present invention relates to combination locks and more particularly to a combination lock capable of being opened by inserting a key into keyhole in addition to turning tumbler wheels to a set series of numbers for opening.
2. Related Art
Locks with features of both pad lock and combination lock are well know. Conventionally, in a key opening operation of the lock a person has to turn a key inserted into a keyhole with one hand and pull a shackle out of a housing for opening with the other hand. This is inconvenient especially when only one hand is available. Also, there is a need of providing means on a combination lock and padlock combination for informing other persons (e.g., customs officer) that a luggage, a container or the like being locked by the combination lock and padlock combination has been opened previously for inspection so that a further opening of the same is not necessary. However, such feature has not been available in prior combination lock and padlock combinations as far as the present invention is aware. Thus, the need for improvement still exists.