In the process of producing concrete, self compacting concrete mixer needs accurate measurement of raw materials such as aggregate, powder, liquid admixture and water. For the mixer truck which has no fixed outdoor work place and needs to be mixed and poured on site, it is necessary to keep the stability and stability of the equipment and frame in the measurement process to ensure the high-quality raw material measurement process. It can be used in all aspects of mixer structure.

骨料的輸送和計量，采用了石子和砂疊加計量輸送的皮帶秤裝置。骨料在卸料進入皮帶秤的過程中，因空間的落差存在，使得卸料門接收信號關閉后，有多余骨料進入到皮帶秤中。通過軟件、電氣控制，使其具備能夠自動補償骨料的落差量，準確達到計量的目標值。皮帶秤使用裙邊皮帶進行骨料輸送，皮帶側邊的裙邊結構能防止砂、石子向側邊漏料，保障計量準確。砂計量皮帶采用變頻控制，能根據計量的需要調節輸送的速度，進一步提高計量精度。

Aggregate transport and measurement, the use of gravel and sand overlay metering conveyor belt scale device. In the process of discharging the aggregate into the belt scale, due to the existence of space gap, after the receiving signal of the discharge door is closed, there is surplus aggregate into the belt scale. Through software and electrical control, it can automatically compensate the drop of aggregate and accurately achieve the target value of measurement. Belt weigher uses skirt belt for aggregate conveying. The skirt structure on the side of belt can prevent sand and stone from leaking to the side and ensure accurate measurement. The sand metering belt adopts frequency conversion control, which can adjust the conveying speed according to the needs of metering, so as to further improve the metering accuracy.

粉料的使用量小于骨料的使用量，為達到精確的計量，需要采用更嚴格的措施。攪拌車在進行粉料的配料工作時，粉料通過帶有變頻功能的螺旋輸送機進行輸送后，進入匹配的粉料秤中計量。通過變頻控制對螺旋輸送速度進行調節，初始計量時快速送料，節省時間；計量接近目標值時慢速送料，把控精度。以此在兼顧效率的情況下，實現了粉料的粗、精計量效果。與皮帶秤類似，螺旋輸送機與粉秤之間也存在高度落差，為提升計量精度，粉料計量系統采用了“一增一減”控制算法。

The usage of powder is less than that of aggregate. In order to achieve accurate measurement, more strict measures need to be taken. When the mixing truck is mixing the powder, the powder is transported by the screw conveyor with frequency conversion function and then measured in the matching powder scale. The screw conveying speed is adjusted by frequency conversion control, so that the material can be delivered quickly in the initial metering, saving time; When the measurement is close to the target value, the feeding speed is slow to control the accuracy. In this way, the coarse and fine metering effect of powder is realized under the condition of efficiency. Similar to the belt scale, there is a height drop between the screw conveyor and the powder scale. In order to improve the metering accuracy, the powder metering system adopts the "one increase and one decrease" control algorithm.

在框架、箱體振動不可避免的情況下，為了保證水和液體外加劑準確計量，采用傳統的單吊點式、以拉式傳感器計量的方式不是選擇。采用拉式傳感器作為計量元件的液體秤，其原理是通過感應計量重量產生的重力應變，轉換為電信號得到重量值，在混凝土攪拌站中應用廣泛。然而由于其感應靈敏的特性，在進行微小目標值計量時，設備框架的振動、外力微小的擾動等都可能導致計量值的偏離，在結構緊湊、計量要求精確、工況復雜、拌合質量要求高的自密實混凝土攪拌車中，應當有更好的設計。通過多次試驗驗證，水、液體外加劑使用流量計進行原材料計量，很好的克服了拉式傳感器的缺點。在液體計量系統中采用的流量計，其工作原理是根據電磁感應原理進行流量測量。

In the case of inevitable vibration of frame and box, in order to ensure the accurate measurement of water and liquid additives, the traditional single hanging point and pull sensor measurement method is not the best choice. The principle of liquid scale using pull type sensor as measuring element is that the gravity strain produced by measuring weight is induced and converted into electrical signal to get the weight value, which is widely used in concrete mixing station. However, due to its sensitive characteristics, the vibration of the equipment frame and the small disturbance of external force may lead to the deviation of the measurement value when measuring the micro target value. In the self compacting concrete mixer with compact structure, accurate measurement requirements, complex working conditions and high mixing quality requirements, there should be a better design. Through many tests, water and liquid admixtures are measured by flowmeter, which overcomes the shortcomings of pull sensor. The working principle of the flowmeter used in the liquid measurement system is to measure the flow according to the principle of electromagnetic induction.

當水、外加劑這類導體在磁場中做切割磁力線運動時，在管道兩端的電極上產生感應電勢。通過測量感應電勢，結合其他已知參數換算為水或外加劑的計量重量。在流量計中，感應電壓信號與平均流速呈線性關系，測量精度高；測量電極內置，抗干擾能力強；計量過程不受到振動因素影響，計量過程穩定平穩。

When conductors such as water and additives cut the magnetic lines of force in a magnetic field, an induced potential is generated on the electrodes at both ends of the pipe. By measuring the induced potential, combined with other known parameters, it can be converted into the weight of water or admixture. In the flowmeter, there is a linear relationship between the induced voltage signal and the average flow velocity, and the measurement accuracy is high; The measuring electrode is built in and has strong anti-interference ability; The measurement process is not affected by vibration factors, and the measurement process is stable.

本文由自動上料混凝土攪拌車進行編寫，想要了解更多的產品及更詳細的精彩內容，請關注我們的網站：http://www.ranhaofz.cn。

This article is written by the automatic feeding concrete mixer. If you want to know more about the products and more detailed wonderful content, please pay attention to our website: http://www.ranhaofz.cn .