(Fig. 1) can be built using various physical magnetic effects in combination with the effect of gravity. To compensate for friction losses and create undamped oscillations in a conventional gravitational pendulum, it is proposed to additionally use the alternate force interaction of two permanent magnets. The change in the nature of the force 1, 2 is carried out by the converter 6. It must ensure the attraction of the permanent magnets 1, 2 of the pendulum at the trigger half-cycle of the pendulum swing, at the moment of their force repulsion after passing the lower point of the pendulum trajectory. This (pendulum) can be built on various principles and physical effects:
a) Using a mechanical turn of the fixed magnet 1 by 180 degrees when the pendulum passes through the lower point - for example: spring type with cam;
b) By abrupt magnetization reversal of a fixed magnet 1 at the lower point of magnet 2 (magnetic Barkhausen effect), moreover, electricity and a magnetic field sufficient for magnetization reversal of magnet 1 are obtained from an inductive winding placed on magnet 1 and connected to an energy storage device;
c) Using a combination of the Barkhausen effect and the thermomagnetic Curie effect. In this case, at the lower point of the trajectory of the pendulum magnet 1, magnet 1 is demagnetized by pulsed heating, magnet 1 is above the Curie point with its pulsed magnetization reversal (the effect of the Barkhausen magnetic trigger) - when magnet 2 reaches the upper point of the trajectory;
d) Mechanical one of the magnets in certain sections of the swing trajectory of the pendulum magnet;
Parasite kotoryj mozhet ubity-Srochno
e) Electromagnetic control magnetic field magnet 1 - (amplification-weakening) - a magnetoelectric mechanical pendulum - supplementing the device with an inductive winding wrapped around a fixed magnet 1 with a capacitor and an oscillation frequency of the circuit equal to the frequency of mechanical oscillations and an adjustable phase of oscillations by this oscillatory electric circuit by means of the inductance of the counter magnetic field of the magnet compensating the magnetic field 1 on the braking sections of the trajectory with an increase in its magnetic field on the accelerating trajectory of the pendulum of magnet 2.
Other original views hours. The clock proposed in this manual, although also electronic, uses the oscillatory movement of the pendulum to keep time. This is the so-called clock with a free pendulum.
The accuracy of such a clock depends on the design of its pendulum, on minimizing the influence of temperature, on the method of supplying energy that maintains the oscillatory movement of the pendulum and receiving energy from the pendulum. In classical mechanical watch the gripping mechanism and a set of gears are responsible for this.
In order for the accuracy of the clock to be as good as possible, the pendulum must oscillate absolutely freely, not burdened by mechanisms. And the energy is transferred in very small portions at the moment when the pendulum is in the lower position and only in the case when the amplitude of the pendulum oscillations decreases below the permissible value. The transfer of energy in too large doses causes an increase in the amplitude of oscillations, which leads to a decrease in accuracy. The amplitude of the pendulum should not exceed a few degrees.
Schematic diagram of the clock
The basis of pendulum clocks is a design with a neodymium magnet bearing attached at the end. At the base there is an induction coil. As a result of the movement of the pendulum directly above the coil, a voltage is induced in the coil, which is transmitted to the PIC12F683 microprocessor, which analyzes the induced voltage and, at the right time, applies a voltage pulse to the coil that supports the movement of the pendulum.
- When the magnet at the end of the pendulum approaches the coil, the induced voltage in the coil is negative,
- when it passes over the middle of the coil, the voltage is zero,
- when it leaves, a positive value.
The amplitude of the pulses induced in the coil depends on the speed of the magnet moving over the coil, and, consequently, on the amplitude of the pendulum's oscillations. By measuring the voltage after a strictly defined time of passage through the pendulum of the equilibrium point, it is possible to assess what the amplitude of the oscillation is, and therefore whether the impulse should be given to the oscillation stimulator or not. The higher the quality factor of the system, the less often it will be necessary to create this pulse.
To display the time, a quartz clock mechanism is used, driven by a 1.5 V battery. In it, we remove the plate with a quartz resonator and a circuit, using only the mechanism itself. We connect the outputs of the motor-coil to the ports of the microcontroller. The MK generates a pulse every second in turn either on one or the second output of the coil.
In total, several different clocks were made with different lengths of the pendulum. The largest was a pendulum with a length of 1000 mm, where the half-period of oscillation was exactly 1 second. There were also oscillations with a half-cycle of 1/3 second (110 mm) and 1/4 second (60 mm). So the momentum for stepper motor was formed, respectively, on the first, third or fourth passage of the pendulum over the equilibrium point.
The clock is powered lithium-ion battery type 18650, they will last for several months of work. For the processor, an LM385-1.2 stabilizer is used, giving a voltage of 1.2 volts. When the processor detects that the battery voltage has dropped below 3.28 V, it is signaled every two seconds. The timer can also work with a battery that has run down to 2 V, but such a deep discharge should be avoided due to the possibility of battery damage.
The induction coil must have several thousand turns. In this watch, 2000-3000 turns of wire 0.12 were wound. The coils do not have a core and are wound on a frame with a diameter of 6 mm. The pendulum shaft must be made of a material with the lowest possible coefficient of thermal expansion, a carbon fiber rod is well suited. The length of the pendulum should be chosen so as to obtain the required period of oscillation. One should take into account the possibility of fine tuning the oscillation period, which is served by an additional weight placed on the pendulum - a brass nut, the rotation of which changes the mass distribution on the pendulum.
Attention: near the magnet at the end of the pendulum should not be ferromagnetic materials - steel nails and screws. Also be careful with brass and copper fittings. A magnet moving in their immediate vicinity excites eddy currents in them, which slow down the movement of the magnet. Therefore, the base of the watch should be made of wood, plastic, laminate, marble, etc.
The electronic circuit contains only the processor in the stand, a zener diode through a 100 kΩ resistor and connectors for the battery, coil and stepper motor. The scheme was assembled on a small printed circuit board cut from a universal plate. Hex files containing processor firmware - .
Not all of us have the ability to predict the future, to learn facts from the past and present, to get answers to questions that do not lie on the surface. However, the beginnings of such abilities are in each of us.
You need to develop them in order to achieve success, or you can use auxiliary attributes to help in magical affairs. This article will talk about such a useful attribute as a magic pendulum that you can make at home yourself.
Making a pendulum
The pendulum can be bought at a specialized store of magical items, but it does not contain any superpowers by itself. After all, the main thing is not the tool, but the ability and experience of using it. In essence, a magic pendulum is an ordinary pendulum made of a thread or a thin rope with a weight tied to it. If you are going to make a pendulum at home, then an ordinary nut, ring, stone, plumb line or any other small object can be used as a load. The main thing is that it should be symmetrical, not outweighed in any direction, hanging on a thread vertically.You can make any length of the thread, but for beginners it is better to use a thread 20-30 centimeters long. At the other end of the thread, it is best to tie a knot that will be comfortable to hold on to. To use such a pendulum, you need to learn how to work with it, to receive information.
Receiving information from the pendulum
Eat a large number of techniques for working with a pendulum. With the help of a pendulum, you can diagnose diseases, look for water, lost things, determine different kinds energy in the home, etc. We will consider the simplest case - getting an answer to question asked. To do this, you first need to determine how the pendulum will show you "yes" and "no". Try to retire, bring your soul and body to a calm state. Take the pendulum by the thread so that the weight on the other end hangs freely. When the weight stops swinging and freezes in place, ask the pendulum: "Show me the answer YES". Your pendulum will begin to swing from side to side or spin in a circle to one side. Remember this movement, with this movement the pendulum will respond positively to your questions. Similarly, ask the pendulum “Show me the answer NO.” Also remember this movement. After that, when you and the pendulum have agreed among themselves how he will answer your questions, start asking him questions that require a YES or NO answer. Start with simple, specific questions from the past to test your pendulum. When you succeed, move on to more difficult questions, to questions about the future.
Good luck with your pendulum! And do not forget that success depends on whether you believe in what you are doing or not. After all, even signs come true only those in which you believe, because all thoughts are material.
Each of us is familiar with the decoration in Chinese watch, which is made in the form of an "eternal" turntable or pendulum. It is not difficult to build such a miracle and it will take no more than half an hour. Let's take a look at the diagram below:
When the supply voltage is applied to the circuit by the switch SB1, the transistor VT1 will be closed, since its base through the coil L1 will be connected to the emitter. There is no bias, the transistor is closed, there is no current through L2 either. Let's tie permanent magnet to the lace and swing our impromptu pendulum in the immediate vicinity of the coils L1, L2 (they are wound on the same frame). When it approaches, an EMF will begin to be induced in the coil L1, which will open the transistor. The closer the magnet, the stronger the transistor opens and the greater the current in the coil L2, which begins to attract our magnet with its magnetic field.
At the moment when the pendulum passes just above the coils, these values are maximum, and as soon as the pendulum begins to move away by inertia, the EMF changes sign and the transistor closes. Thus, the pendulum is attracted only in the first half of the period, in the second it goes by inertia. Just like a real swing, which we swing by swinging our legs in the first half of the swing. Diode VD1 prevents generation that may occur at the resonant frequency of the circuit L1, L2.
Now let's talk about the design of our swing. Coils L1 and L2 are wound simultaneously with a wire with a diameter of 0.08 - 0.1 mm on a frame of suitable sizes. For example, on this one:
We wind the more, the better, until filling. The more turns, the less voltage the pendulum will require to operate. When connecting the coils, phasing must be observed - the beginning of the first is connected to the end of the second. As a core, a cut of any iron bolt or even the whole bolt if it's short. Before use, this bolt must be burned - heated red-hot on gas and cooled in air.
It is better to take a transistor with the highest possible transfer coefficient. Any low-power germanium (even silicon worked for me) direct (p-n-p) conductivity will do. If the conductivity of the transistor is reversed (n-p-n), then it doesn’t matter either - just change the polarity of connecting the power source and the VD1 diode.
Perform a pendulum or swing to your taste. It is only important that the magnet, located on the base of the pendulum, passes a few millimeters from the core of the coil. The magnet itself is any, the more powerful the better, but you won’t have to look for anything special. A piece of a “black”, ferrite magnet from a dynamic head or an iron one from an old children's motor is perfect.
A pendulum or any other galvanic element is used as a power source, which is enough for many months of operation of the structure, and the SB1 switch can be safely abandoned, since in the quiet position of our pendulum the transistor is closed and the current consumption of the circuit is minimal. If the magnet is very weak or the swing is too heavy for it, then you can increase the supply voltage to 3 V by turning on two elements in series.
For a child, and with a solid assembly, you can develop the idea to, for example, an office souvenir.
The basis of the toy is the simplest overhanging circuit (although of course it is better to do it on the board), consisting of a transistor, a diode and a specially wound coil hidden in the bottom. The “seat” of the swing is a magnet, it is better to choose a neodymium one, there are a lot of them now, although a regular one will do.
The coil is wound with a double wire with a cross section of approximately 0.25-0.3 each, about 1500 turns, i.e. 2 copper wires are taken in parallel and wound onto a coil. The diagram shows that the end of the first wire is connected to the beginning of the second. I chose the shape of the coil from logical considerations oval, because. a magnet passing over it will interact better along the length of the larger diagonal of the ellipse. I did not use the core, so you can experiment with it. It is better to wind carefully, turn to turn, but not necessarily.
A direct conduction transistor, you can take MP39 ... 42, any diode, a regular 1.5 volt battery. For convenience, it is better to make a switch.
I apologize for the homemade assembly, but I did it in my school days on pure enthusiasm from a diagram from my father's old notebook with diagrams, so I don't really know where it came from, and I just wanted to see how it works as soon as possible.
It starts simply, turn on the device and push the magnet, after a couple of seconds you will notice how intensely the pendulum begins to oscillate. The system will work better if it is possible to create a resonance, i.e. the equality of the frequencies of the circuit and the natural frequency of the pendulum, which is calculated by the formula. Here it is achieved by adjusting all parameters of the pendulum. It is better to fix the connecting rod on 2 bearings, and not on the 1st like mine.
