Automatic hand wash. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Home, household, hobby
Comments on the article
The constant rise in the cost of utilities makes us look for new ways to save water and electricity. The proposed photoelectronic device (Fig. 1) allows you to automate the process of washing and turn on the water only when the hands are under the tap.
Rice. 1. Schematic diagram of a photoelectronic device (click to enlarge)
The device consists of a short pulse generator on the elements DD1.2...DD1.6, a key on the transistor VT1, the circuit of which is taken from [1], a photosensor with an amplifier on the DD4 chip, a delay counter on DD3 and an RS flip-flop on DD2.1 and DD2.2.
Short pulses are emitted by the IR LED HL1. When hands approach the sensor, the radiation reflected from them is perceived by the VD1 photodiode. The pulses are amplified by the DD4 chip and from the output 10 of the microcircuit are fed to the input 13 of the DD2.4 element. At the input 12 DD2.4 are clock pulses from the generator. When they coincide with the output pulses DD4, a logical "11" appears at the output 2.4 DD0, which switches the RS flip-flop on the elements DD2.1, DD2.2 to a single state ("1" at output 3). Then the transistor VT2 opens and the electrovalve of the KM1 water tap turns on.
If you remove your hands from the tap, the pulses from pin 10 DD4 stop, "3.1" is set at the inputs R of the counters DD3.2 and DD0, and thus the counters are allowed to work, the filling of which occurs with pulses from the generator. As soon as "1" appears at output 12 DD3, the RS flip-flop is reset and the valve closes. The delay is made so that the tap does not turn off when you remove your hands for a short time, for example, when soaping. This time can be increased if input 1 DD1.1 is connected to output 13 or 14 DD3, or reduced by connecting this input to output 6 (5) DD3. I do not recommend removing the counters, since without them the unstable operation of the solenoid valve is possible.
Place the device on the wall in such a way that the valve reliably operates when hands are brought to the faucet and turns off when they are removed. The sensitivity of the photosensor is regulated by a trimming resistor R7.
Rice. 2. Printed circuit board of photoelectronic device
The device is assembled on a single-sided printed circuit board with dimensions of 28x84 mm (Fig. 2). The DD4 chip and the VD1 LED must be shielded with thin tin on both sides of the printed circuit board.
Literature
- Y. Vinogradov. Infrared presence sensor. - Radio, 2002, No. 1 S.26.
Author: S. Abramov, Orenburg, asm_oren@mail.ru; Publication: cxem.net
See other articles Section Home, household, hobby.
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 A device that decomposes sounds without the help of digital technology
31.03.2017
Hussein Esfahlani, from the Federal Institute of Technology in Lausanne (Switzerland), as part of a group of electrical engineers from Switzerland, has created a device, an acoustic prism, capable of decomposing sound into frequency components by purely physical means, without the use of digital technology.
The device is a hollow aluminum casing 40 cm long with a number of holes on the side. The inner space of the casing is divided into a number of chambers by flexible polymeric membranes. When these membranes oscillate, they transmit sound from chamber to chamber with a delay depending on its frequency. As the delayed sound waves exit the holes, they are refracted in different directions so that the lowest frequency sound (similar to red light) can be heard at the end closest to the source, and the higher frequency sound (similar to blue light) from the more distant hole. . "It's like how a drop of water or a glass prism refracts light of different colors to different angles," Esfahlani said.
It can be used to isolate significant frequencies from incoming white noise, or pinpoint the exact location of a sound source at a particular frequency. "This is a very elegant and efficient way to distinguish between audio frequencies," commented Nicholas Fang, professor of mechanical engineering at MIT, who was not involved in the work.
|
Other interesting news:
▪ New synchronous DC/DC voltage converters
▪ Dual operational amplifier EL1510
▪ Singing can increase life expectancy
▪ The world may be left without chocolate
▪ Efficient batteries
News feed of science and technology, new electronics
Interesting materials of the Free Technical Library:
▪ section of the site Firmware. Article selection
▪ article Fasting and its tolerance. Basics of safe life
▪ What was Germany like in the XNUMXth-XNUMXth centuries? Detailed answer
▪ article Juniper prickly. Legends, cultivation, methods of application
▪ article Programming AVR microcontrollers in Ubuntu. Part 1. Encyclopedia of radio electronics and electrical engineering
▪ article Switching power supply for memory devices. Encyclopedia of radio electronics and electrical engineering
Leave your comment on this article:
All languages of this page
Home page | Library | Articles | Website map | Site Reviews
www.diagram.com.ua
2000-2024
Arabic
Bengali
Chinese
English
French
German
Hebrew
Hindi
Italian
Japanese
Korean
Malay
Polish
Portuguese
Spanish
Turkish
Ukrainian
Vietnamese