苹果分级机设计

摘要

随着社会消费水平的不断提高，人们在购买苹果时越来越注重苹果的内在品质。商场根据果实的品质进行分级销售已经逐渐成为一种趋势。目前我国出口或内销的苹果分级筛选一般还是采用原产地人工分级方式，效率低、强度大。因此，本文设计一种具有无损自动分级功能的苹果分级机，具有十分突出的现实意义。

本文设计的苹果分级机主要包括三个部分：苹果输送系统、分级执行系统和控制系统。输送系统通过第一级水平传送带、第二级向上倾斜传送带，下落到第三级输送链上的托盘上。然后再通过称重传感器来测量苹果的重量，通过PLC控制系统来实现水果的分级。本课题是将机械，电气控制，传感器等技术有机结合，并将其综合应用到了苹果分级机的设计理念之中，最终实现了分级机的自动化，提高了苹果分级的效率和质量。

关键词：苹果分级，输送机，传感器，电磁铁，PLC

ABSTRACT

With the increasing levels of social consumption,people pay more and more focus on the inherent quality of the apple.Shopping malls graded apples according to the quality of the

fruit sales which have become a trend.China's exports or the domestic apple grading screening general or origin artificial classification.Such a low grade efficiency and strength work.Therefore,to design a non-destructive apple grading machine of automatic grading function,with a very prominent practical significance.

In this paper,the design of the apple grading machine mainly consists of three parts:

apple conveyor system,gr ading the implementation of systems and control systems. Transportation system through the first level of the second stage of the conveyor belt, upward-sloping conveyor belt,the whereabouts of the third level of the conveyor chain on the tray.And then through the load cell to measure the weight of the apples through the PLC

control system to achieve the classification of fruits.This topic is the organic combination of mechanical,electrical,sensor,signal conversion technology and comprehensive application to

the design concept of the apple grading machine,and ultimately a grading machine automation,improve the efficiency of apple grading and quality.

Key words:apple grading,conveyor,sensor,solenoid valve,Programmable Logic Controller

目

录

1 绪

论------------------------------------------------------------------------------------------------------

1 1.1 1.2 1.3 1.4 课题来源及目的 (1)

课题意义 (1)

国内外发展状况 (2)

本课题的设计要求 (3)

------------------------------------------------------------------------- 2 3 苹果分级系统总体设计 2.1 机械系统设计.............................................................................................................. 2.2 电气控制系统设计思路.............................................................................................. 2.3 小结.............................................................................................................................. 输送系统的设计计算---------------------------------------------------------------------------- 3.1 第一级输送带的设计.................................................................................................. . (4)

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6 7

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3.2 3.3 3.4 3.5 第二级输送带的设计计算 输送链的设计计算.................................................................................................... 输送链的传动机构设计计算.................................................................................... 分级执行系统的设计 (13)

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23 27 4 5 控制系统的设计-----------------------------------------------------------------------------------29

4.1 控制系统中PLC 的应用 (29)

4.2 传感器原理 (31)

4.3 放大器LM339N (31)

4.4 PLC 控制设计 (33)

4.5 小结............................................................................................................................36 结论---------------------------------------------------------------------------------------------------- 37

--------------------------------------------------------------------------------------------- 参考文献 致谢------------------------------------------------------------------------------------------------------- 38

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