The display digital technology of medical centrifuges is a typical expression of analog technology. The knobs select operating parameters (such as speed, temperature and time) and display the data with the hands of the dial. The disadvantage is that the reading value of the selected parameter and the data is interfered by the operator and the person of the reading person, and the control precision is poor. And every time you do this, the repeatability is poor. Although some centrifuges display digital display (such as the value of the knob and digital display), although the reading is improved, the value principle is still analog technology; the typical display form of digital display is user-friendly, keyboard operation, digital display The whole computer control of programmable operation, the core of which is intelligent control, is realized by computer. All parameters required for the operation of the centrifuge (such as speed, temperature, time, acceleration and deceleration rate files, etc.), keyboard operation input, and digital display, so the choice of operating parameters and readings error is minimal. And because it is a programmable operation, a set of operating parameters can be numbered and accessible.
In the current society, the production of medical centrifuges is mainly concentrated in Beijing, Shanghai and Hunan. The process of this centrifuge is relatively simple, generally using a centrifuge, a region according to the density of the sample solution centrifuge, gradient of cells, viruses, deoxyribose Nucleic acid (DNA) separation and collection, samples and added samples are used in a continuous manner and are widely used in production processes outside, and are now widely used in laboratory equipment. Due to the DC inverter motor or brushless DC motor of medical centrifuge, the general speed is adjustable, and the speed is high, to reduce the weight, the drum, and the outer plastic or other alloy materials which are generally not easy to react. The internal light alloy or other is often used. Material to react.
In the inspection work, due to the relatively concentrated use time of the medical centrifuge opening and stopping, the motor and the machine are worn and consumed greatly. If the maintenance work cannot be done regularly on time, it is easy to cause the failure of the stop or the slow speed, which directly affects the failure. The normal operation of the inspection work. Therefore, it is very important to be able to grasp the methods of promptly and quickly eliminating various types of failures of the centrifuge and ensure that the centrifuge is always in good working condition.
Because the motors used in medical centrifuges are generally series motors. It consists of two parts, the stator and the rotor. The stator is a concentrated fixed magnetic pole composed of a core and a field coil. The rotor is composed of a core and a rotor coil and a commutator. The function of the brush is to connect the stator coil to the key components of the rotor coil via the commutator. The circuit working principle of the series-excited motor is that the current flows from the power source through the stator field coil, the brush, and the commutator into the rotor coil, and then the brush and the stator field coil return to the power source to form a loop. The field coil and the rotor coil are connected in series by a commutator. The currents in the lines are equal, so only if the series circuit is unobstructed, the motor can work normally at the required speed.
It can be seen that the working condition of the brush directly affects the normal operation of the motor. However, due to the contact between the brush and the commutator, wear, consumption or spring failure, the brush open circuit and the commutator are easily disengaged. It is the main cause of medical centrifuge shutdown or slow speed failure.