1. The definition of multihead weigher
The engineering name is also called "computer combined weighing instrument". It is composed of multiple independent weighing units with feeding and discharging structures. The computer uses the principle of permutation and combination to automatically optimize the load of the weighing unit.
2. The types of multihead weigher
As the name implies, a multihead weigher has many "heads", which is actually a "weighing bucket". According to the types of buckets commonly used in the food packaging industry today, it is divided into 8 buckets, 10 buckets, 12 buckets, 14 buckets, 16 buckets, 20 buckets, 24 buckets and so on. According to the type of use environment, it is also divided into waterproof type, anti-corrosion type, anti-collision type, general-purpose type, etc., which are used in food packaging, daily chemical, tobacco, and hardware (particle) industries. According to the shape, it is divided into double door, big column type, double chute, low noise single door type.
3. The working principle of the multihead weigher
1) The hoist feeds the material through the loading pan to concentrate the materials on the main vibrating pan, and then through the vibration of the main vibrating pan, the materials are evenly distributed on the main vibrating pan to the linear vibrating pan.
2) When the material in the feeding tray is not or not enough to be detected by the material level photoelectric detector, a signal is sent to the main board, and then a feeding signal is sent to the hoist through the main board to feed material.
3) The line vibration machine vibrates, and the material is sent to each buffer hopper through the amplitude and the line vibration feeding time.
4) The stepping motor works, and the buffer bucket is opened to send the materials in the bucket to the weighing bucket. When the weighing hopper participating in the combination discharges or when the material in the weighing hopper is insufficient, the material in the buffer hopper will automatically flow into the weighing hopper.
5) In the weighing hopper, the weight signal of the material is generated by the sensor, which is processed by the AD module to become a digital signal and transmitted to the main board of the intelligent control device through the data bus.
6) The CPU on the main board reads and records the weight of each weighing bucket, and then selects the combination weighing bucket closest to the target weight through calculation, analysis, combination, and screening, and send out the ready signal that the combination weigher has weighed the material and is ready to discharge.
7) When the CPU receives the signal of permission to discharge from the packaging machine, the CPU sends a command to start the driver to drive the stepper motor, open the selected weighing hopper, and unload the material into the chute into the collecting hopper. If there is no collecting hopper, it will directly enter the packaging machine and send a discharge signal to the packaging machine that the material has been discharged.
8) After the weighing hopper is discharged, the buffer hopper will replenish, weigh, and combine the weighing hopper in time to prepare for the next discharge.