Which combination lock to choose - mechanical or electronic. How to do it yourself. How to make a combination lock yourself

Code lock Overall a very convenient and practical thing. With its installation, there is no need to constantly carry a bunch of metal keys in your pocket in order to open this or that shed. To do this, you just need to remember the code.

Combination locks, in general, can be divided into two categories according to their characteristics: mechanical and electronic.

Most electronic combination locks made on K561TM2, KTZ trigger microcircuits or on microcircuits specialized just for this purpose. Particularly sophisticated designs are appearing these days on microcontrollers and sensors. Three simple circuits presented by Dmitry Nifashev on www.radiokot.ru.

First, let's look at the combination lock on the 4017 chip (HEF4017BP). The lock code consists of four numbers pressed in a given sequence. To find the code, you will have to go through 10,000 options.

The proposed scheme (Fig. 1) will help to assemble a simple combination lock with high encryption strength.

Rice. 1. Scheme of a simple combination lock

The diagram shows:

♦ using buttons S6-S9 “correct” code numbers;

♦ using the SI-S5 buttons, numbers that are not needed at all in the code.

Initially, there is a logical “1” at pin 3 of the IC.

When the "S6" button is pressed, a logic "1" is applied to the input of the counter 14, and a logic "1" appears at pin 2. In the same way, after pressing the "S7" button, a logic "1" appears at the output 4, and after pressing the button "S8" - at output 7.

After pressing the last correct digit “S9”, logical “1” appears at output 10. Transistor VT2 opens, the relay is activated and connects the load with its contacts. Relay activation is indicated by an LED.

If you press any of the “incorrect” numbers (SI-S5), logical “1” will go to pin 15 (“Reset” - reset to its original state), and the selection of the code will have to start over. Lock on K561IE9 chip and field effect transistor KP501A.

Combination lock diagram (Fig. 2) fundamental differences It has little in complexity from the previous scheme.

Rice. 2. Scheme of a simple combination lock with an extended keyboard

The chip is a four-digit Johnson counter. The principle of operation of this circuit is similar to the circuit described above, although there are more buttons on it.

Finally, let’s look at the lock on two K561TM2 microcircuits (Fig. 3).

Rice. 3. Scheme of a simple combination lock on two K561TM2 microcircuits

Works electrical diagram as follows. At the initial moment, when power is applied, the Cl, R1 circuit generates a pulse to reset the triggers (there will be a log “0” at outputs 1 and 13 of the microcircuits).

When you press the button of the first digit of the code (in the diagram - SB4), the moment it is released, trigger D1.1 will switch, i.e. a log will appear at output D1/1. “1”, since there is a log at input D1/5. "1". When you press the next button, if there is a log at input 0 of the corresponding trigger. “1”, i.e. the previous one worked, then log. “1” will also appear at its output. The last one to fire is trigger D2.2, and so that the circuit does not remain in this state for a long time, transistor VT1 is used. It provides a delay in resetting triggers.

The delay is made due to the charging circuit of capacitor C2 through resistor R6. For this reason, at output D2/13 the signal is logic. "1" will be present for no more than 1 second. This time is quite enough for relay K1 or electromagnet to operate. The time, if desired, can easily be made significantly longer by using capacitor C2 of a larger capacity.

To increase resistance to hacking, the number of “unnecessary” buttons can be increased. Up to any quantity - it all depends on your desire and circumstances.

Note.

While dialing the code, pressing any incorrect digit resets all triggers.

In conclusion, it should be noted that over time, the “necessary” buttons begin to wear out and differ from all the others. So it is advisable to occasionally swap the buttons to ensure even wear.

A combination door lock is a locking device, to open which you need to set or specify the correct combination of numbers. Among them, two main types can be noted - mechanical and electronic. Despite the difference in technology, they have one principle - to open the entrance, you must enter the correct code on the device’s keyboard.

Combination locks for entrances - their advantages and disadvantages

Combination locks for entrances have both advantages and disadvantages over their analogues. The main advantages are:

• no need to make and keep an entrance key with you;
• low cost of the mechanism;
• Losing your key will not prevent you from getting home;
• the presence of backlit keys in electronic and electronic-mechanical devices;
• opportunity to change secret code castle

The most significant disadvantages include:

• the ability to distribute the code among strangers;
• keypads quickly become unusable;
• abrasions on the keys make it possible to select a code for the lock;
• the need to regularly change the code and remember it.

In addition, each type of lock has its own strengths and weaknesses.

Mechanical combination locks for entrances

When the door to the entrance is slammed, the return spring in the mechanical device is charged, the start head is located in the bar, and the latch is retracted. Pressing the correct combination of buttons moves the correct plates, releasing the lock cage. If you release the buttons, the return spring will ensure that the latch returns to its original position.

Despite the simplicity of the device, assembling it with your own hands is quite problematic.

The only way to open a mechanical lock is to enter the correct code, but despite this, the degree of protection is only sufficient to isolate it from bystanders.

The lock can be installed on both right and left doors. To open it from the inside, you just need to pull back the lever. It is recommended to use at least three digits in the code combination.

To recode the lock, you need to remove the screws, spring set and lever. Next, you need to position the levers of the buttons used for the new code at a bevel towards the center of the lock and assemble the device back. You need to check the operation of the lock with the front door open. IN winter time VD-40 lubricant should be used on moving parts.

Electronic combination locks

An electronic lock with a code for the entrance has more attractive design, a more convenient procedure for changing and entering codes, as well as a number of various related functions. There are enough parts sold on radio markets that allow you to assemble such a device yourself.

Locks with digital code It is advisable to choose according to the following criteria:

• ability to unlock the device with a master card;
• backlighting of the keys;
• weather protection;
• international certificate;
• Possibility of locking different doors using a single key.

The main components from which electronic push-button locks are made:

• The device itself, which includes an electromagnetic drive of the locking mechanism. In order to ensure the mobility of the lock bolt, an electrical impulse must be sent to its electromagnet. This is only possible if the code in the receiver matches the combination on the storage medium. This process occurs on special locks that differ from ordinary wires coming out in a pile.
• An outdoor control panel, which is a reading device that does not include any control electronics. It receives impulses emanating from indoor unit control and if the signal code matches, the reader is activated.
• The internal control device, which is the main control center of the electronic lock. It is he who sends an impulse to the electromagnets of the device, ensuring its opening. Most of these locks lock, just like any mechanical slamming device.
• Source uninterruptible power supply. It is a necessary component for electronic locks– otherwise, if there is a power outage, it will be impossible to enter the room. Despite the low power of the device, it can ensure the operation of an electric lock for several days. The UPS is a small device located in a hidden place.

Scheme of an electronic combination lock for the entrance - how to assemble it yourself

The combination lock operates on a 4017 chip. This is a multifunctional crystal and now it will also serve as a guard, in the form of an easy-to-make combination lock with high level encryption strength. In order to find a code for it, you will have to try 10,000 options, and an incorrectly pressed key does not signal an error in any way. The cipher consists of a combination of four digits entered in a certain sequence. Considered combination lock scheme:

The design of such a device is the same as other electronic locks on microcircuits. Contacts S6-S9 correspond to the numbers that are present in the working code - these are the “necessary” numbers. The keys S1-S5, on the contrary, show numbers that are not included in the code.

• When there is power, there is a voltage on the 3 ms pin, designated logical “1”.
• When the "S6" key is pressed, this voltage appears at the input of the counter "14" and it is triggered, sending the voltage to pin 2.
• The same thing happens after pressing “S7”-“S8” - this sends voltage to pins 4 and 7, respectively.

When the counter records all four correct presses of the code digits, current is supplied to contact number 10, which opens transistor VT2, which supplies power to the relay control circuit. The latter is activated and provides load connection, which is indicated by the LED.

You can assemble an electronic combination lock with your own hands. About this in the video:

Foolproof protection

If, while typing the code, any of the “wrong” buttons (S1-S5) is pressed, voltage is applied to pin 15, which resets the counter, returning the entire circuit to its original position. This is not displayed in any way on the indicators, which makes password guessing much more difficult.

Unauthorized access can be made almost impossible by simply adding a time relay to pin 15, quietly blocking all keys for at least 60 seconds.

In this case, if you enter the code incorrectly, you will have to wait a minute before entering it again. The attacker will not know this, and even if he accidentally guesses the password, it is not a fact that he will type it while the time relay is inactive.

If you know about this feature, then it will take 10-12 thousand minutes to select a password - you will have to continuously enter passwords for about 8 days to select the desired combination. The reliability of such a solution increases almost to its maximum values.

The assembled circuit is only part of the work - now you need to adjust the opening/closing of the lock bolt. To do this, you can either make a magnet or use a ready-made activator, for example a car one.

Using these methods, you need to be aware that in the first case, when there is a power outage, the lock of the front door will automatically open, and in the second case, on the contrary, it will remain closed. Therefore, the second option, equipped with a UPS, is more preferable.

Hello everyone, in this article I will show you how to make a simple but reliable combination lock without using a complex and expensive microcontroller.

Combination lock diagram

The basis of our circuit is a pulse counter - the CD4017 microcircuit. The domestic analogue of this microcircuit is K561IE8, and we use buttons as an input pulse generator.

If you want to install a combination lock on your door yourself, it is important to understand its structure. Depending on which model is used, its connection diagram and operating principle may differ. It is important to distinguish between these features, so this issue should be considered in more detail.

Combination locks are either electronic or mechanical

Types of castles

Each entrance door must be equipped with a lock. With a properly selected locking mechanism, home safety requirements will be met. Important criteria when choosing a device are:

• degree of burglary resistance;
• type of mechanism and lock scheme;
• reliability;
• privacy level.

Today the range of goods is so huge that you can find a good lock in any price category. Complex mechanisms deserve special attention. Some people don't find best solution for your home, except to make a combination lock at the entrance.

• Mechanical. A standard mechanism based on the use of physical force to activate the locking bolts.
• Electronic and magnetic. Powered by mains or battery. Operation requires a radio signal or a magnetic key.
• Combined. They can work as electromagnetic models, and in the event of a lack of power, they switch to the mode of a regular lock with a key.
• Mortise. They are installed on the door leaf from the outside of the door and have a visible end plate.
• Nested. They are mounted at the door manufacturing stage directly inside the door leaf.

Types of door combination locks depending on the principle of operation

Based on the type of locking device, combination locks are classified in the same way as regular locks.

Features of mechanical devices

Previously, mechanical combination locks were used almost everywhere. They were actively installed on front door entrances in apartment buildings. Also, the scope of their application extended to the entrance area to utility and industrial premises. The principle of operation of the mechanics is based on the introduction of a code combination of several numbers, which set the crossbars in motion and unlocked the door when the necessary buttons were held.

The design of a modern mechanical combination lock is somewhat complicated, since older models turned out to be not very reliable due to the ease of selecting a combination based on pressed-in operating buttons. Today, their scheme is more often based on the sequential introduction of numbers, but the mechanism itself has remained approximately the same.

The advantage of mechanical models is that their connection diagram is extremely simple. They do not require connection to batteries, and therefore it is enough to just embed the product into the canvas and attach the mating part to the box.

Reprogramming a mechanical lock with your own hands also does not pose any particular difficulties. To do this, you need to do the following: disassemble the case and change the access code to a new combination, connecting the buttons with the crossbars.

The advantage of a mechanical combination lock is its ease of connection.

Electromagnetic models

Of course, purchasing a mechanical lock is a good budget option, however, electromagnetic models are more reliable and efficient; they are installed on the front door in apartments, private houses, offices, etc. Such locks have the main difference - they operate on electricity. Energy consumption is small, and therefore you don’t need to worry about extra kilowatts on the meter. In addition, you can use rechargeable batteries so as not to lay a cable to the nearest network.

• Electronic. The basic model is an electronic lock that you can program yourself. It can work according to different principles. In some products, the combination reception scheme is based on its manual input on the keyboard. Other locks operate by receiving a radio signal, which sends a special key programmed for storage the required code. In order for the system to work, it is necessary to provide the lock with power. For convenience, some models are equipped with a display. Buttons can be either regular push buttons or touch buttons, as in more expensive and modern products.
• Magnetic. They also require power from batteries or mains, but the principle of operation of the magnetic lock is based on a slightly different approach. The main element is the magnetic key, which is the carrier of the code. It can be in the form of a tablet, key fob or card. In order to open the door using a magnetic lock, you need to attach the key to the receiving plate. After processing the signal, the mechanism is activated and the door opens. The device of a magnetic door lock is clearly demonstrated by the intercom.

Electromagnetic door locks are considered the most reliable for security

A magnetic and electromagnetic lock are essentially the same device. The main condition is the use of a magnetized key to enter the code and unlock the mechanism. In exclusively electronic models, the circuit is based on the delivery of an electrical impulse.

Installation Rules

The diagram for installing a combination lock on a door with your own hands for mechanical models is quite simple. The idea is to attach a digital panel with a secret mechanism to the canvas, and insert a counter plate into the canvas. The simplest models contain crossbars that inside can be moved manually thanks to a special lever or button.

Installing a mechanical combination lock is quite simple and does not require special skills

But how to install an electromagnetic lock on a door with your own hands? Here you need to have basic skills in working with power-powered devices. Also for specific model magnetic or electronic product must be accompanied by instructions with step by step description technologies for connecting block elements. Ideal option– when the connection diagram is displayed not only in text form, but also schematically.

The technology for installing an electric lock with your own hands is as follows:

1. Determine the position of the lock panel on the door.
2. Mark the exact location where the panel will be inserted.
3. Drill holes in the canvas according to the marks.
4. Cut a hole of appropriate size to accommodate the lock block and locking mechanism.
5. Next you need to connect the code panel to the lock drive.
6. For an electric lock, you need to make access to the power supply.
7. Then you need to program the lock by setting an access code on the device and check that the mechanism is working correctly.

Installing a combination electric lock on your front door will allow you to increase reliability and security. If you do everything correctly, you will not regret the decision you made and will prevent damage to the device during long-term use.

An electronic combination lock is not only an effective security mechanism, but also a rather effective and stylish solution that can well decorate many modding projects made in the appropriate styles with its appearance. Of course, for design purposes you can make a fake electronic combination lock, but it would be much better to make a working solution. And since we are modders, we will do it ourselves.

Good day to all modders and not only! On the eve of writing this guide, I was unable to find any material on this topic online, so I set about writing my own theoretical article on creating an electronic combination lock. Such locks are quite simple to manufacture and can have a huge number of code options, with any number of characters, but they also have their disadvantages:

• numbers cannot be repeated (theoretically they can, but in practice this does not make sense. Why - read on :)
• the buttons are divided into “correct” and “incorrect”, which means that no matter how much you press the “correct” button (in any order), the rest of the correctly entered code will not go astray
• You can guess the code by the sound of the relay (hide it away)

And just a request: if someone can figure out how to get rid of these shortcomings, write.

If you are satisfied with everything, then let's get started. We will need:

• fiberglass (preferably falginated), although one of my friends managed to solder it on cardboard :)
• thin wires
• if fiberglass with metal, then you need a plastic, enamel or glass container, ferric chloride and nitro enamel
• buttons (necessarily working for closing and opening)
• reed relays (RES*** depends on the voltage, you need as many as the number of code characters)
• solvent
• drill + drill bit 1.5 mm
• if the piece of fiberglass is too large, then use a jigsaw/dremel/guillotine
• printer
• well, and as always, straight arms + head on shoulders

• Sprint Layout 4.0

After all the preparations, you can move on to the stage of developing the circuit (if you are too lazy to create your own circuit, you can go straight to the end of point 1, there I will post the circuit diagrams for the lock with code 3846).

Creating a scheme for a combination lock

First you need to understand the principle of operation of the lock. Its main part is the reed switch relay (hereinafter referred to as the reed switch):

When voltage is applied to the coil, it switches the contact from one leg to the other and, accordingly, if the circuit opens, the contact returns back. This means that if you close a previously empty leg with one contact of the coil and make the system shown in the figure, then when you press the button the reed switch will switch the contact from one leg to another, and after
releasing the button, the circuit will not open (exception: if the circuit opens before “-in”, then the contact will return back and the entered code will be reset (that’s what we use)).

You can set up as many such groups as you like and put together the code using the puzzle method. Now, to get a full-fledged lock, we open the circuit in front of the first group and fill all the remaining buttons of the future keyboard with the same buttons, but working to open (i.e., so that when pressed they do not close the circuit, but open it). In the simplest case, something like this will come out:

Based on this, you can draw a diagram of a lock with any code. For those who are too lazy to create their own diagram, here is the diagram (normal and mirror, respectively) of the lock with code 3846:

* There are jumpers on the buttons - these are not tracks, these are legs that are initially closed
** You will have to draw all the details yourself, because... There are no macros needed
*** Wires are marked in red (to draw: press sides/active side/mask side (1))

Making a combination lock

So, we have a diagram, the required number of reed switches (as many as there are buttons for closing), the buttons themselves, material and tools. You can start manufacturing.

• We print the diagram in two copies (and one is a mirror copy), and cut off the normal one.
• Glue it to the unlined side with PVA glue.
• We drill holes through the paper for the legs of the reed switches and buttons, after which it is better to wet and remove the paper. The faster everything happens, the easier it will be to remove the paper, but Don't rush when drilling!. Greater precision needed!
• If your fiberglass laminate is not lined, you will have to solder the wires and skip steps 4-7.
• We look at the mirror diagram and draw future paths on the falginated side with nitro enamel.
• After the enamel has dried, place the board in a plastic/enamel/glass container and fill it with ferric chloride solution
• We wait until the metal on the board is “eaten up.”
• We take out the board, pour water on it, wipe off the enamel with solvent, wash it, dry it, check the tracks for contact.
• We solder all the parts into place on the side without tracks, you may have to solder the wires (where it was not possible to add tracks)
• If necessary, we make a case, connect the power and enjoy the result.

You can use different watch faces.