Introduce an advanced quantitative automatic weighing instrument - computer combination scale

【Abstract】This paper mainly introduces the origin and development process of an advanced quantitative automatic weighing instrument-computer combination weighing scale. The technical characteristics and advantages of the computer combination scale are analyzed, and the application fields and objects of the current computer combination scale are introduced. It is also proposed that the computer combination scale should be localized as soon as possible to facilitate the popularization of applications.

First, the problem is raised and the solution

In the 1970s, the Japan Agricultural Association raised the issue of weighing green peppers to related weighing companies. In Japan, green peppers are usually sold in supermarkets in the form of bagged quantitative packaging. If the quantitative value of green pepper per bag is 120 grams, it is very difficult to load 120 grams because a single green pepper is heavier and the difference is Large, less loaded with the interests of consumers, loaded with more costs related to the enterprise. The traditional way is to weigh manually, that is, weigh on a static electronic scale, a green pepper and a green pepper, add up to 120 grams. However, if it is added to 115 grams, it is almost impossible to find a 5 gram green pepper. It is necessary to take a smaller green pepper from 115 grams and add another larger green pepper. If the weight is much larger than 12 grams or less than 120 grams, the above work needs to be repeated, so that the weighing efficiency is extremely low, and it is difficult to achieve the result close to the target weight (quantitative value). After extensive investigation and research, Japanese technicians successfully solved the above-mentioned green pepper weighing problem by using the combined weighing principle.

The computer combination scale is also called the selection combination scale, which is composed of a plurality of weighing units with independent feeding and discharging structures. The general computer combination scale is composed of 8 to 32 weighing units. The computer uses the arrangement and combination principle to automatically calculate the load amount of each weighing unit, and obtains a combination of zuijia and zui close to the quantitative value for packaging. As shown in the figure, for example, a computer combination weigher with ten weighing units, each weighing unit is weighed during weighing, and the weight data in each weighing hopper is read into the computer and optimized by the computer. According to the combination number, 10 weighing units can achieve a total of 1023 combinations, and the computer selects a combination of Zui close to the target weight value from the 1023 combinations. In this way, the above-mentioned manual repeated matching and it is difficult to achieve quantitative values ​​can be solved.

Second, the technical characteristics of the computer combination scale

1, high weighing accuracy

The computer combination scale guarantees the weighing accuracy from the following three aspects:

a, subsampling

For example, the computer combination weigher of ten weighing units mentioned above is read from the data of ten weighing units to * times sampling in the weighing process, and the computer obtains the data and then performs the preferred combination; if 3 weighing units The object is called, but the weight data of the three weighing units is sampled again, this is the second sampling; if the data of the two samples is inconsistent, the computer will recombine, such as two The sub-sampled data is consistent, and the computer combination scale is discharged; this ensures that the weight of the discharged material is exactly the same as the predetermined weight.

b, automatic zero function

Because some of the weighed dust will stick to the weighing bucket wall during the weighing process, it will not affect the accuracy of the next weighing. The solution of the computer combination scale to solve this problem is: 1 When the material is released, the weighing bucket is generally opened 4-5 times to reduce the residual amount of dust of the object. 2 The computer combination scale will also automatically zero the weight of the weighing hopper. The dust adhering to the weighing hopper will be regarded as zero weight, which will not affect the accuracy of the next weighing.

c, anti-ground vibration

General computer combination scales work in the workshop, and there are often power motor equipment running in the workshop to generate vibration on the ground. The human body generally does not feel this kind of vibration, but it will be sensed for high-sensitivity computer combination scales to make weighing data. Unstable This computer combination scale adds an inductive vibration sensor in addition to the load cell to remove the sensed vibration component from the weighing sensor data to obtain reliable data.

2, weighing fast

a, digital signal processing technology

The digital processing of the computer combination scale is completed by a special computer chip, which ensures that the weight analog signal is converted into a digital signal after rapid digital filtering, thereby ensuring time to complete the "secondary data sampling" function described above.

b, stepper motor control hopper opening and closing

Due to the controllability of the stepping motor, the opening and closing speed and size of the weighing hopper can be adjusted, and the opening and closing of the weighing hopper can be adjusted to be small at a small weighing to achieve high speed.

c, adjustable vibration tank

The amplitude and vibration time of the vibration groove are adjustable, and the adjustment is fine, which can meet the requirements of accuracy and speed. Another important feature of computer combination scales is that there are corresponding application technologies according to different materials, such as waterproof type, fragile type, easy stick type, mixed weighing, number weighing, etc., which can be applied to various aspects. need.

Third, the conclusion

Since the birth of the world's * computer combination scale in 1972, it has created a new era of quantitative packaging in the world. Due to its fast weighing speed, good dynamic precision and high degree of automation, it is widely used in packaging potato chips, candy, puffed food, Quantitative packaging for biscuits, frozen vegetables and other industries.

The combination weighing scale quantitative weighing block is the key equipment for the automatic production of food factories. In the past, China relied on imports from Japan, Australia and other countries. Due to the high price, it hindered the widespread application and popularization of computer combination scales. Now Zhongshan Weipike Packaging Machinery Co., Ltd. has adopted advanced computer components and components. Its stable performance, sincere after-sales service and closer to the price of domestic food terminals have won the favor and respect of many food manufacturers. The rapid improvement and superior grade of the Wipak combination scale makes the computer combination scale originally regarded as “aristocratic product” no longer listed as a patent of a large enterprise. More domestic companies pursuing high speed and high efficiency have eliminated In the past, the cup-type or full-manufacturer manual weighing and weighing packaging production line used a high-tech, more automated combination weighing scale to weigh the packaging system to arm itself. This set off a "new revolution" to improve production and equipment management!