Touch time relay for electromechanical toys. Encyclopedia of radio electronics and electrical engineering

Encyclopedia of radio electronics and electrical engineering / Clocks, timers, relays, load switches

 Comments on the article

The device is intended for installation in a children's electromechanical toy and allows you to extend the service life of chemical current sources. It will automatically turn off the power to the structure after a specified time. For children's toys, the presence of such a function is relevant, since a child can lose interest in it at any time without turning off its power with the built-in switch.

Fig. 1

The time relay circuit is shown in fig. 1. After the supply voltage is applied, the capacitor C2 is discharged, all transistors are closed and the electric motor (or motors) is not powered, and there is no current consumed. The relay is started by simultaneously touching the sensor elements E1, E2 with your fingers or palm, while the opening voltage will be applied to the gate of the field-effect transistor VT2. Following it, transistors VT3 and VT4 will open, and the electric motor will start to work. If you release the sensor elements, the transistor VT2 will close, but the capacitor C2 will start charging through the resistors R2, R3, R6, the emitter junction of the transistor VT3 and the open channel of the transistor VT4. Due to this current, VT3 and VT4 remain open and the supply voltage is supplied to the electric motor. In this case, the voltage drop across the transistor VT4 will not exceed 50 mV, and the maximum current through it should not exceed 3 A.

When the charging of the capacitor C2 is over, the transistors VT3 and VT4 will close and the motor will be de-energized. For the elements indicated in the diagram, with a supply voltage of 3 V and a load current of 0,5 A, the power-off delay will be about 120 s. Touching the sensor elements again will open the transistors VT2-VT4, and the capacitor C2 will quickly discharge through the open transistors VT2, VT4 and the current-limiting resistor R6. Therefore, after releasing the sensor elements, the shutter speed countdown will begin again.

The emitter junction of the transistor VT1 works as a micropower zener diode and protects the gate of the field effect transistor VT2. Capacitor C1 suppresses high-frequency interference, resistor R1 is current-limiting.

Fig. 2

Electric motor M1, power switch SA1 and battery GB1 are regular elements of the toy. The rest of the parts, except for the sensor elements, are placed on a single-sided printed circuit board, the drawing of which is shown in fig. 2. If no holes are drilled in the board, the elements can be soldered directly to the corresponding contact pads, which will reduce the overall dimensions of the mounted board. Resistors C2-23, P1 -4 are used, capacitor C1 is K10-17, K10-50, the rest are small-sized low-profile imported oxide, C2 should have as little leakage current as possible, so it is desirable that it be tantalum. Instead of the KP505G field effect transistor, any of the KP505, BSS88, BSS295 series, as well as an instance from the KP501, KP504, ZVN2120 series with a threshold voltage of not more than 2 V at a drain current of 100 μA, will do. Transistors 2SA993 can be replaced by any KT3107, 2SA104, 2SA109, 2SA1048 series. Replacing the field effect transistor FDD6530A - AP9916H, P45N02LDG. During installation, the gate and source terminals of the field-effect transistors are connected with a wire jumper to prevent damage to them.

As sensor elements E1, E2, you can use metal trim elements of the toy, for example, decorative door handles of a car model, while the body itself must be plastic. The elements are placed so that they are closed by the fingers or palm when the toy is picked up.

Setting up the device consists in setting the exposure time by selecting capacitor C2. For uncontrolled electromechanical toys, it is preferable to set it in the range of 15 ... 30 s, and for radio-controlled toys - 2.10 min. It should be noted that when the supply voltage of the device decreases, the exposure time also decreases. Instead of an electric motor, there may be another load, for example, incandescent lamps or various electronic components.

Author: A. Butov

See other articles Section Clocks, timers, relays, load switches.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

Machine for thinning flowers in gardens 02.05.2024

In modern agriculture, technological progress is developing aimed at increasing the efficiency of plant care processes. The innovative Florix flower thinning machine was presented in Italy, designed to optimize the harvesting stage. This tool is equipped with mobile arms, allowing it to be easily adapted to the needs of the garden. The operator can adjust the speed of the thin wires by controlling them from the tractor cab using a joystick. This approach significantly increases the efficiency of the flower thinning process, providing the possibility of individual adjustment to the specific conditions of the garden, as well as the variety and type of fruit grown in it. After testing the Florix machine for two years on various types of fruit, the results were very encouraging. Farmers such as Filiberto Montanari, who has used a Florix machine for several years, have reported a significant reduction in the time and labor required to thin flowers. ... >>

Advanced Infrared Microscope 02.05.2024

Microscopes play an important role in scientific research, allowing scientists to delve into structures and processes invisible to the eye. However, various microscopy methods have their limitations, and among them was the limitation of resolution when using the infrared range. But the latest achievements of Japanese researchers from the University of Tokyo open up new prospects for studying the microworld. Scientists from the University of Tokyo have unveiled a new microscope that will revolutionize the capabilities of infrared microscopy. This advanced instrument allows you to see the internal structures of living bacteria with amazing clarity on the nanometer scale. Typically, mid-infrared microscopes are limited by low resolution, but the latest development from Japanese researchers overcomes these limitations. According to scientists, the developed microscope allows creating images with a resolution of up to 120 nanometers, which is 30 times higher than the resolution of traditional microscopes. ... >>

Air trap for insects 01.05.2024

Agriculture is one of the key sectors of the economy, and pest control is an integral part of this process. A team of scientists from the Indian Council of Agricultural Research-Central Potato Research Institute (ICAR-CPRI), Shimla, has come up with an innovative solution to this problem - a wind-powered insect air trap. This device addresses the shortcomings of traditional pest control methods by providing real-time insect population data. The trap is powered entirely by wind energy, making it an environmentally friendly solution that requires no power. Its unique design allows monitoring of both harmful and beneficial insects, providing a complete overview of the population in any agricultural area. “By assessing target pests at the right time, we can take necessary measures to control both pests and diseases,” says Kapil ... >>

Random news from the Archive AIWA TVX-F21D1 - CRT TV with built-in DVD player 19.01.2004 Aiwa introduced the TVX-F21D1. This is a 21" CRT TV with a built in DVD player. The player supports DVD-Video and MP3 formats recorded on DVD-R, DVD-RW, DVD+R, DVD+RW, CD-R and CD-RW discs. The stereo system of the TV has a 2.1 formula and a built-in subwoofer. Digital amplifier power - 18 W, there are 5 equalizer presets. Used in TVX kinescope F21D1 from SONY - FD Trinitron. 100 Hz progressive scan, screen aspect ratio -16:9. Dimensions: height 653 mm, depth 530 mm, width 496 mm, weight - 29,8 kg. Sales are scheduled for February 1, 2004, the cost of TVX-F21D1 will be $500.

Other interesting news:

▪ Scholars love short headlines

▪ Smartphone Nokia Lumia 1520

▪ Emission-free aircraft

▪ Video games can boost a child's intelligence

▪ Sirius 16 Gen 1 Gaming Laptop on Linux

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ section of the site Power supply. Article selection

▪ article Second I. Popular expression

▪ article What was the subject of the dispute between the commander and the crew that caused the crash of the Soviet plane? Detailed answer

▪ article Manufacture of an electronic payment. HAM Tips

▪ article Universal matching device. Encyclopedia of radio electronics and electrical engineering

▪ article Powerful converter for powering household appliances, 100 watts. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

All languages ​​of this page

Arabic	Hebrew	Polish
Bengali	Hindi	Portuguese
Chinese	Italian	Spanish
English	Japanese	Turkish
French	Korean	Ukrainian
German	Malay	Vietnamese

Home page | Library | Articles | Website map | Site Reviews

www.diagram.com.ua
2000-2024