| A combination lock is the type of lock where | | | | opened.Certainly these type of combination locks are |
| sequences of numbers or symbols are used to open | | | | generally more secure that the multiple dial locks and |
| a lock rather than a key. Often the sequence of | | | | yet they do have some weaknesses as well. Certainly |
| number or symbols used is a permutation rather than a | | | | early combination padlocks which were made by |
| real combination and these may be entered either by | | | | Master Lock could be opened by pulling on the shackle |
| entering them using a single rotation dial (which | | | | and turning the dial until it stopped and thus each |
| interacts with several discs or cams) or by a set of | | | | numeral involved in the locks combination could be |
| several rotating discs with inscribed numerals or | | | | revealed.However, the more recent models of the |
| symbols (which directly interact with the locking | | | | Master padlock now come with 40-position dial and |
| mechanism itself).Firstly we will look at multiple dial | | | | this has a weakness where it gives away the last |
| locks and which is one of the simplest type of | | | | numeral in the locks combination and the first two |
| combination locks. These are often used for low | | | | numerals of the lock have a mathematical relationship |
| security situations such as a bicycle lock which has | | | | to this one. Because of this weakness it reduces the |
| several rotating discs with notches cut into them. The | | | | possible number of combinations a person can try to |
| lock is secured by a pin that has several teeth on it | | | | open it from 64,000 to a mere 100 instead, which |
| which then hook into the discs that rotate around it. | | | | results in the lock being opened in a very short |
| Thus when the discs and notches are aligned with the | | | | time.Unfortunately an inexpensive padlock is not the |
| teeth of the pin the lock can open. Unfortunately the | | | | solution either as these are often susceptible to them |
| disadvantage of this type of lock is that it is considered | | | | being shimmed, which is often used to release the |
| to be one of the least secure types of combination | | | | shackle without the actual combination being |
| locks available today.The opening of such a lock can | | | | entered.There are many other designs available and |
| be done without the combination it all depends on the | | | | many doors lock now use a combination lock system |
| slight irregularities which will occur during the machining | | | | which requires the user to enter a numeric sequence |
| of the locks parts. So unless the lock has been | | | | on to a keypad for them to gain entry. However, such |
| precisely machines (the pin pulled outward) then you | | | | locks usually require the use of electronic circuitry to |
| are likely to find that one of the teeth will pull more | | | | be effective. But the one main advantage of such a |
| strongly than others on its corresponding disc. Once | | | | system as this is that if it is used for the door of a |
| this disc is rotated and a slight click can be heard this | | | | large office then each member of staff can be |
| tells the person that the tooth has become placed in its | | | | provided with the number that they will need to gain |
| correct notch and thus this procedure can be | | | | access and thus eliminate the use of supplying them |
| repeated with the other remaining discs which will | | | | with keys which could be either lost or stolen.The only |
| result in the lock being opened (a correct combination | | | | real disadvantage of this type of lock is that if the |
| on such a lock can be found in a very short period of | | | | code number for entry is discovered by someone |
| time).Next we come on to the single-dial locks, these | | | | who is not employed by the company, or the number |
| are normally found on padlocks or safes and will often | | | | is not changed regularly, then access to the property |
| just use a single dial which then interacts with several | | | | can be gained by an intruder (such as a burglar).Allison |
| parallel discs or cams. Such locks are normally opened | | | | Thompson a work from home mum living in Spain with |
| by the rotation of the dial clockwise to the first numeral | | | | over 15 years experience in the property |
| and then counter clockwise to the second and so on | | | | management field. She has set up a number of site |
| until in this alternating fashion until the last numeral has | | | | relating to property matters as well as being the |
| been reached. Typically the cams inside the lock have | | | | partner in a small real estate company. The sites she |
| an indentation or notch on them and it is only when the | | | | has set up deal with all aspects of property and how |
| correct combination has been entered and the notches | | | | to make the most of what you have both inside and |
| or indentations have become aligned that the latch will | | | | outdoors. |
| be able to fit into them and the lock can be | | | | |