The use and working principle of the weight sorter and the main components of the metal detector

The use of weight sorting machine : mainly used for automatic weight detection, on-line identification or weight grading selection in various automated packaging lines, widely used in online high-speed industries such as pharmaceutical, food, health care products, daily chemicals, batteries, light industry, etc. Package check weighing application.

Working principle of weight sorting machine: The working principle of electronic scale consists of electronic components (weighing sensor, amplifier circuit, AD conversion circuit, single chip circuit, display circuit, keyboard circuit, communication interface circuit, regulated power supply circuit, etc.) Description: When the object is placed on the weighing pan, the pressure is applied to the sensor, the sensor is deformed, so that the impedance changes, and the excitation voltage is changed to output a varying analog signal. The signal is amplified and output to the mode by the amplifying circuit. The digital converter converts the digital signal that is easy to process and outputs it to the CPU operation control. The CPU outputs the result to the display according to the keyboard command and the program until the result is displayed.

The packaged products are weighed and tested by the checkweigher, and are returned to the original conveyor belt by qualified ones. If they are not qualified, they are rejected (or alarmed), and the products are classified and counted according to the settings, and the feedback signal is automatically provided to adjust the correction feeding equipment. , text display fault alarm information, a variety of graphical statistics display and other functions.

A typical metal detector system consists of the following four main components:

1. The detector coil or the detection head has a built-in "balanced coil". The three coils are wound on a non-metallic frame or a former, and the coils are completely parallel, and the middle coil (transmitting coil) is connected to a high-frequency current. magnetic field. The two coils located on either side of the intermediate coil are receiving coils. Since the two coils are identical and maintain the same spacing as the transmitter, their induced electromotive force is exactly the same. When these coils are connected in reverse, the electromotive forces cancel each other out, thereby forming a "zero output", that is, reaching an equilibrium state. It is then filled with cement to ensure that the magnetic field is in a state of dynamic equilibrium when no product passes, and is not affected by external environments such as temperature changes, vibration, electromagnetic interference. During the test, the product passes through three coils in succession. If metal foreign matter is contained, the balance of the magnetic field will be broken, and an induced current will be generated to detect various metal foreign objects.

2. User interface / control panel, common includes touch screen type and button type, generally installed directly on the detection head. However, if the head is too small or installed in a location that is inconvenient or inaccessible, you can use a connecting cable to install it remotely.

3. Transmission system: used to make the product pass through the opening. The most commonly used transmission device is horizontal conveyor belt. For different product applications, gravity drop type (powder or granules transported in pipes), horizontal pipe type (liquid and Fluid) and plastic guides commonly used in the pharmaceutical industry.

4. Automatic rejection system: used to remove any infected product from the production line, usually installed on the transmission system. There are many different types, including air blow, pusher, flap and so on. The type of rejection system will depend on the product that needs to be tested.