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小型多功能切菜机的设计【6张CAD图纸和说明书】

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摘 要

蔬菜是人体所必需的一种食品,而且食用方法多样。所以要把蔬菜加工成各种形状,如条状、片状等;单靠人工来完成既费时、费力而且也不好加工。目前,多功能切菜机多为价格昂贵的大型设备,不适用于农民个体生产及小型工厂的食品加工;为克服这种缺点,本设计在查阅了大量相关文献资料的基础上,进行切菜机的设计,经过理论计算及校核,设计了一种小型多功能切菜机。该机主要由进料斗、下料斗、切削刀、刀盘及电动机组成,其工作原理是利用根茎类蔬菜的自由落体实现进料,通过切削刀旋转将下料斗中的蔬菜进行切片或切丝,最后成品由出料口出料。实现了能够连续进料和出料,片厚度、丝粗细可调的功能,具有生产率高、功耗低、安全可靠、加工质量好等优点。


关键词:蔬菜,切削,电动机


DESIGN OF THE VEGETABLE CUTTING MACHINE


Abstract

Vegetables are essential food for our body, and we uaually make them in various ways. In the process of eating, the vegetables need to be made into a variety of shapes, such as strip, sheet and so on; It is time-consuming, laborious and it is not easy to cut the vegetables well when we only depend on human themselves. Currently, multi-functional shredders are mostly expensive and large, they do not apply to individual farmers or small factories which produce food; In order to overcome this drawback, the paper makes a design of a small multi-purpose shredder on the foundation of a lot of relevant literature on the conduct shredder design, and it is also through some theoretical calculations and checking. The shredder consists of a feed hopper, hopper, cutting knife, the knife dish and motor, and its working principle is to use the freefall of root vegetables to realize the feed, then through the cutting knife to make the vegetables to slice or shred. Finally, the finished product come out from the discharge port. It is able to achieve a continuous feed and discharge, and it also has a function to adjust the  slice thickness, wire thickness. It is a product which is with high productivity, low power consumption, safe, reliable, good processing quality and other advantages.


KEY WORDS:vegetables, cutting, motor


目  录

摘 要 I

ABSTRACT II

第1章 绪论 1

1.1前言 1

1.2国内外的发展 1

1.2.1 国外的发展 1

1.2.2国内切菜机技术的发展概况 1

1.3本设计的目的、意义及方案设计 2

1.3.1 本设计的目的和意义 2

1.3.2 方案设计 2

第2章 机械部分的设计与实现 6

2.1 总体设计 6

2.2 主传动部分设计 6

2.2.1 电机的选择 6

2.2.2 主传动方式选择 8

2.2.3带传动的设计计算 9

2.2.4 小带轮的结构设计 12

2.2.5 大带轮的结构设计 13

2.3 主轴部件的设计 14

2.3.1 轴的材料选取和结构图 14

2.3.2 计算主轴上的功率、转速、转距 14

2.3.3 初定轴的最小直径 14

2.3.4 轴的结构尺寸确定 15

2.3.5 轴承的设计 15

2.3.6 主轴支承方案的确定 16

2.3.7 主轴的校核计算 17

2.3.8 轴承的校核 22

2.4 键的选择和校核 23

2.4.1 键的选择 23

2.4.2 键的校核 23

2.5 刀具的设计 24

2.5.1 新月型刀具 24

2.5.2 圆盘刀具 25

2.5.3 刀具的最后设计 26

2.5.4 料斗的设计 26

第3章 机架的设计 28

3.1 机架设计要求 28

3.2 机架材料的选用及壁厚选择 29

3.3 机架整体设计 29

参 考 文 献 31

致  谢 33

附 录1英文文献 34

附 录2中文翻译 48


第1章 绪论

1.1前言

蔬菜是人生活中必不可少的营养丰富的食品之一,可为人体提供必需的维生、矿物质、膳食纤维等有益于人体健康的功能成分。随着人们生活水平的不断提高,生活节奏加快,对食用方便、营养丰富、经过加工的精细蔬菜的需求越来越大,对产品的品质要求越来越高。蔬菜出口在我国起步虽晚,但由于中国蔬菜富含营养、品种齐全、质优价廉,深受各国消费者的青睐,因而近几年蔬菜出口发展十分迅速,己成为创汇农业的支柱产业。

随着现在的快餐业迅速崛起,对茎块的食物的需求越来越多。像土豆薯条、薯片等休闲食品的消费急剧增长。这给茎块食物的加工带来了勃勃生机与活力。在茎块作物的加工过程中需将其切成片。因此切菜机应运而生。按刀片安装形式的不同切菜机可以分为盘刀式、滚刀式和离心式三种。

1.2国内外的发展

1.2.1 国外的发展

国外的切菜机技术始于六十年代,到七十年代已经发展成熟,八十年代中期,大部分切菜机都可以加工直径125mm以上的蔬菜,象瑞士的迈尔-布格耶斯公司的卧式内圆切菜机,切割蔬菜直径最大可以达到304.8mm。八十年代中期后的一、两年,切菜技术发展到了鼎盛时期,相当多的多功能全自动切片机相继商品化。从而诞生了世界上一些著名的切菜机厂家,如瑞士 Meyer­Burger AG 公司的 TS 系列机,日本TokyoSemitsu株式会社的 TSK(若干)系列机,日本 Okamoto Machine 株式会社的 ASM 系列机,美国 STC 公司的 STC 系列机等。发展到现在,就切菜机的功能而言,已经相当齐全,而且复合化,切菜的方式也多种多样。

1.2.2国内切菜机技术的发展概况

我国的切菜机技术始于七十年代初期,目前我国切菜机的主要方式有以下几种:

(1)直线往复式切菜机。直线往复式切菜机的结构简单,但效益低。因此它应用于工作要求不高、效益低的场合。

(2)圆盘旋转式切菜。圆盘旋转式切菜机的机构简单也有较高的生产效益,因此它广泛应用于各种场合。

(3)水枪式切菜。水枪式切菜机耗水量打,只能切出平直的片,因此它的应用不是十分广泛。

(4)圆形(内圆切片的外圆切片)切菜。圆形式切菜机有很高的工作效率,但是结构复杂,设计较困难,因此它应用于工作效率要求相当高的专业领域。我国的切菜的研究开发方面虽然已有 30 年的历史,近几年来切菜机的研制发展也非常迅速,但是与发达国家相比目前仍然有一定的距离,研制的切菜机没有得到大面积推广应用。


内容简介:
切菜机的设计摘 要蔬菜是人体所必需的一种食品,而且食用方法多样。所以要把蔬菜加工成各种形状,如条状、片状等;单靠人工来完成既费时、费力而且也不好加工。目前,多功能切菜机多为价格昂贵的大型设备,不适用于农民个体生产及小型工厂的食品加工;为克服这种缺点,本设计在查阅了大量相关文献资料的基础上,进行切菜机的设计,经过理论计算及校核,设计了一种小型多功能切菜机。该机主要由进料斗、下料斗、切削刀、刀盘及电动机组成,其工作原理是利用根茎类蔬菜的自由落体实现进料,通过切削刀旋转将下料斗中的蔬菜进行切片或切丝,最后成品由出料口出料。实现了能够连续进料和出料,片厚度、丝粗细可调的功能,具有生产率高、功耗低、安全可靠、加工质量好等优点。关键词:蔬菜,切削,电动机VIDESIGN OF THE VEGETABLE CUTTING MACHINEAbstractVegetables are essential food for our body, and we uaually make them in various ways. In the process of eating, the vegetables need to be made into a variety of shapes, such as strip, sheet and so on; It is time-consuming, laborious and it is not easy to cut the vegetables well when we only depend on human themselves. Currently, multi-functional shredders are mostly expensive and large, they do not apply to individual farmers or small factories which produce food; In order to overcome this drawback, the paper makes a design of a small multi-purpose shredder on the foundation of a lot of relevant literature on the conduct shredder design, and it is also through some theoretical calculations and checking. The shredder consists of a feed hopper, hopper, cutting knife, the knife dish and motor, and its working principle is to use the freefall of root vegetables to realize the feed, then through the cutting knife to make the vegetables to slice or shred. Finally, the finished product come out from the discharge port. It is able to achieve a continuous feed and discharge, and it also has a function to adjust the slice thickness, wire thickness. It is a product which is with high productivity, low power consumption, safe, reliable, good processing quality and other advantages.KEY WORDS:vegetables, cutting, motor目 录摘 要IABSTRACTII第1章 绪论11.1前言11.2国内外的发展11.2.1 国外的发展11.2.2国内切菜机技术的发展概况11.3本设计的目的、意义及方案设计21.3.1 本设计的目的和意义21.3.2 方案设计2第2章 机械部分的设计与实现62.1 总体设计62.2 主传动部分设计62.2.1 电机的选择62.2.2 主传动方式选择82.2.3带传动的设计计算92.2.4 小带轮的结构设计122.2.5 大带轮的结构设计132.3 主轴部件的设计142.3.1 轴的材料选取和结构图142.3.2 计算主轴上的功率、转速、转距142.3.3 初定轴的最小直径142.3.4 轴的结构尺寸确定152.3.5 轴承的设计152.3.6 主轴支承方案的确定162.3.7 主轴的校核计算172.3.8 轴承的校核222.4 键的选择和校核232.4.1 键的选择232.4.2 键的校核232.5 刀具的设计242.5.1 新月型刀具242.5.2 圆盘刀具252.5.3 刀具的最后设计262.5.4 料斗的设计26第3章 机架的设计283.1 机架设计要求283.2 机架材料的选用及壁厚选择293.3 机架整体设计29参 考 文 献31致 谢33附 录1英文文献34附 录2中文翻译48第1章 绪论1.1前言蔬菜是人生活中必不可少的营养丰富的食品之一,可为人体提供必需的维生、矿物质、膳食纤维等有益于人体健康的功能成分。随着人们生活水平的不断提高,生活节奏加快,对食用方便、营养丰富、经过加工的精细蔬菜的需求越来越大,对产品的品质要求越来越高。蔬菜出口在我国起步虽晚,但由于中国蔬菜富含营养、品种齐全、质优价廉,深受各国消费者的青睐,因而近几年蔬菜出口发展十分迅速,己成为创汇农业的支柱产业。随着现在的快餐业迅速崛起,对茎块的食物的需求越来越多。像土豆薯条、薯片等休闲食品的消费急剧增长。这给茎块食物的加工带来了勃勃生机与活力。在茎块作物的加工过程中需将其切成片。因此切菜机应运而生。按刀片安装形式的不同切菜机可以分为盘刀式、滚刀式和离心式三种。1.2国内外的发展1.2.1 国外的发展国外的切菜机技术始于六十年代,到七十年代已经发展成熟,八十年代中期,大部分切菜机都可以加工直径125mm以上的蔬菜,象瑞士的迈尔-布格耶斯公司的卧式内圆切菜机,切割蔬菜直径最大可以达到304.8mm。八十年代中期后的一、两年,切菜技术发展到了鼎盛时期,相当多的多功能全自动切片机相继商品化。从而诞生了世界上一些著名的切菜机厂家,如瑞士MeyerBurgerAG 公司的 TS 系列机,日本TokyoSemitsu株式会社的TSK(若干)系列机,日本OkamotoMachine株式会社的 ASM 系列机,美国STC公司的 STC 系列机等。发展到现在,就切菜机的功能而言,已经相当齐全,而且复合化,切菜的方式也多种多样。1.2.2国内切菜机技术的发展概况我国的切菜机技术始于七十年代初期,目前我国切菜机的主要方式有以下几种:(1)直线往复式切菜机。直线往复式切菜机的结构简单,但效益低。因此它应用于工作要求不高、效益低的场合。(2)圆盘旋转式切菜。圆盘旋转式切菜机的机构简单也有较高的生产效益,因此它广泛应用于各种场合。(3)水枪式切菜。水枪式切菜机耗水量打,只能切出平直的片,因此它的应用不是十分广泛。(4)圆形(内圆切片的外圆切片)切菜。圆形式切菜机有很高的工作效率,但是结构复杂,设计较困难,因此它应用于工作效率要求相当高的专业领域。我国的切菜的研究开发方面虽然已有 30 年的历史,近几年来切菜机的研制发展也非常迅速,但是与发达国家相比目前仍然有一定的距离,研制的切菜机没有得到大面积推广应用。1.3本设计的目的、意义及方案设计1.3.1 本设计的目的和意义针对目前切菜机噪音大、电气化程度低、成本高、刀具的磨损大、不能切叶类蔬菜、切片或切丝的形状不规则、厚度不均等缺点,本次设计将对噪音大,成本高,切片切丝的形状不规则、厚度不均来进行改进。1.3.2 方案设计方案一:直线式多用切菜机1.结构及原理图图1是直线式多用切菜机原理图,该装置的主要工作部分由切刀1、压蔬菜锟2、锟筒3、运送带4和压蔬菜轮5组成。在工作过程中,蔬菜由进料处由传送带3输送,并通过压蔬菜锟2和压蔬菜轮5进行压紧,然后由旋转圆盘刀具1进行切削。其中压蔬菜轮5可以上下移动。5423料斗处11-旋转圆盘切刀 2-压蔬菜辊 3-辊筒 4-运送带 5-压蔬菜轮图1直线式多用切菜机原理图2.该方案的优缺点优点:一是设计先进,节能高效居同类产品领先水平;二是对蔬菜的体型大小要求不是很严格。缺点:一是电机调速精度低,切丝长度不易控制;二是噪音大,电气化程度低,成本高。方案二:离心式切菜机1.结构及工作原理图图2是离心式切菜机原理图,该装置的主要工作部分由切片厚度调节旋钮1、拨动臂2、切片筒3和刀片4 组成。在工作过程中,蔬菜通过进料处放入,通过 拨动臂2使蔬菜高速旋转,利用离心力使蔬菜紧切切片筒3由刀片4进行切削。其中切菜的厚度可以通过切片厚度调节旋钮1来进行调节。1432进料处1-切片厚度调节旋钮 2-拨动臂 3-切片筒 4-刀片 图2离心式切菜机原理图2.该方案的优缺点优点:一是具有结构紧凑、合理和操作简便;二是调整维修方便。缺点:一是对刀具的磨损大。二是不能切叶类蔬菜。方案三:旋转式切菜机1.结构及工作原理图图3是旋转式切菜机原理图,该装置的主要工作部分由料斗1、叶轮及其刀片2、电动机3、皮带机皮带轮4和传动轴5。在工作过程中,蔬菜在向上倾斜的料斗1内依靠重力自动向下运动,通过利用电动机3带动皮带机皮带轮4和传动轴5 运动,然后由叶轮及其刀片2对蔬菜进行旋转切削。345211-料斗2-叶轮及其刀片3-电动机 4-皮带机皮带轮 5-传动轴 图3旋转式切菜机原理图2.该方案的优缺点优点:结构紧凑、坚固耐用、易于维修和更换刀具、可提高生产率、降低劳动强度。缺点:切片或切丝的形状不规则,厚度不均。方案的确定:对比上述三种方案,可以发现,方案三体型较小,操作方便,相比其他两种方案清洗简单,成本较低,适用于家庭,食堂,饭馆使用,而且固定可靠,设计简单。结合上述三种方案的对比,本设计将采用方案三完成切菜机相关参数的理论计算和对比。64第2章 机械部分的设计与实现这一章主要介绍本切菜机系统的机械部分,包括主运动和进给运动方式的设计和实现,以及各主要零部件的校核计算。2.1 总体设计图2-1是旋转式切菜机原理图,该装置的主要工作部分由料斗1、叶轮及其刀片2、电动机3、皮带机皮带轮4和传动轴5。在工作过程中,蔬菜在向上倾斜的料斗1内依靠重力自动向下运动,通过利用电动机3带动皮带机皮带轮4和传动轴5 运动,然后由叶轮及其刀片2对蔬菜进行旋转切削。321541-料斗 2-叶轮及其刀片 3-电动机 4-皮带机皮带轮 5-传动轴 图2-1旋转式切菜机原理图2.2 主传动部分设计2.2.1 电机的选择目前最常用的主要是交流电动机,它可分为两种:1.三相异步电动机。2.单相交流电动机。第一种多用在工业上,而第二种多用在民用电器上。下面以三相异步电动机为例介绍其基本工作原理起先,形成一个闭合的笼型绕组。定子三相绕组可接成星形,也可以接成三角形。综上分析可知,三相异步电动机的基本工作原理是:(1)三相对称绕组中通入三相对称电流产生圆形旋转磁场。(2)转子导体切割旋转磁场感应电动势和电流。(3)转子载流导体在磁场中受到电磁力的作用,从而形成电磁转矩,驱使电动机转子转动。经查阅手册及相关资料,只要刀盘轴转矩满足T5N.m,即可满足一般蔬菜的切削。由于刀盘太快了反而不好,不能保证质量,初步拟定转速450r/min,取转矩T=15 N.m (2.1) (2.2)由于课题要求使用三相异步电动机,所以选用三相异步电动机,额定电压380V。查阅机械课程设计手册,可选用小功率异步电动机Y系列。该系列的特点是单相电容起动,起动力矩大,起动电流小,适用于满载起动的机械。这样在进行蔬菜切削时完全可以将蔬菜放进料斗以后在开动机器。根据功率和转速,由机械设计课程设计手册查出的电动机型号有以下两种传动比选择方案符合,如下表据机械设计课程设计手册可知有:表2-1 电动机的类型方案电动机型号额定功率/W电压/V转速r/min电机质量kg1Y801-20.753802830162Y802-40.75380139018综合考虑电动机和传动装置的尺寸,质量以及传动比。采用V带传动,采用第二种方案,设计V带传动比为3即可,不必另外安装减速器。故采用第二种方案。因此选定电动机的型号是Y802-4。该电动机的主要外型和安装尺寸如下表2-2:表2-2 电动机主要外形尺寸中心高外形尺寸安装尺寸地脚螺栓孔直径轴伸尺寸装键部位尺寸8028516517012510010406其主要外形安装尺寸如图2-2图2-2主电机外形图2.2.2 主传动方式选择常见的传动类型有链传动、齿轮传动和带传动。链传动的优点:能够保证准确的传动比,压轴力较小,传递功率大,过载能力强;能在低速重载高温条件下及尘土大的情况下良好工作,传动效率高。缺点是:工作中有冲击和噪声,磨损后易发生跳齿,链条的铰链磨损后,使节距变大造成脱节,安装和维护要求较高。齿轮传动的优点是:能保证瞬时传动比恒定,平稳性高,传递运动准确可靠,传递的功率和速度范围较大,结构紧凑,工作可靠,可实现较大的传动比,传动效率高,使用寿命长。缺点是:造价较高,制造、安装成本高。带传动的优点是;结构简单,适于两轴中心距较大的场合,造价低廉,并且带富有弹性,可缓冲吸振,传动平稳无噪声。缺点是:传动带需张紧在带轮上,需要专门的张紧措施,且对轴和轴承的压力较大,传动效率较低(一般0.940.96)。考虑到切菜机要求传动平稳,并且结构简单,成本较低,所以选择带传动。在带传动中,有平带传动,V带传动,多楔带传动和同步带传动。其中V带传动应用最广。V带的横截面呈等腰梯形,带轮上也做出相应形状的轮槽,传动时,V带只和轮槽的两个侧面接触,所以在相同的张紧力下,V带能产生更大的摩擦力,并且V带传动的传动比较大(i7),结构紧凑,现已标准化和大量生产,因此选择V带传动。V带种类中选择普通V带,其当量摩擦因数大,工作面与轮槽粘附性好,允许包角小,适用于小功率传动。结合电机的选择结果,最终确定传动方式为电机通过传动比i=3的普通V带驱动主轴转动。2.2.3带传动的设计计算(1) 确定计算功率计算功率是根据传递功率,并考虑到载荷性质和每天运转时间长短等因素影响而确定的,即(2.3)式中,Pd为计算功率,传递功率P在此为步进电机最大功率,为工作情况系数,查机械设计手册13得=1.1。步进电机最大功率按下式计算: (2.4)式中,Pw指工作机所需最大工作功率,指电动机至工作机的传动总效率代入式(2.4)中得P=0.084kW,将其代入式(2.3)中得Pd=0.092kW(2) 选择带型普通V带分为Y、Z、A、B、C、D、E、F七种带型,截面高度与节宽的比值为0.7。根据Pd和小带轮的转速n确定带型,查机械设计手册14,选择A型带。V带和带轮有两种尺寸制,即有效宽度值和基准宽度值。普通V带是基准宽度制用带。根据机械设计手册14表V带(基准宽度制)的截面尺寸查得A型带的截面尺寸为:节宽bp=11mm,b=13mm,h=8.0mm,楔角=40。如图所示:图 2-3 带截面示意图(3) 传动比式中,为小带轮转速,为大带轮转速(4) 小带轮基准直径按照机械设计手册14表普通和窄V带(基准宽度制)直径系列选取小带轮的直径=75mm。(5) 大带轮基准直径(2.5)式中,为大带轮的基准直径,为弹性滑动率,取0.02,代入公式(2.3)得=246.5mm,再根据机械设计手册14普通和窄V带(基准宽度制)直径系列选取标准值=265mm。(6) 带速普通V带m/min符合条件(7) 初定轴间距要求结构尽量紧凑,取mm(8) 所需带基准长度根据机械设计手册14表普通基准长度系列选取相近长度,选取实际长度=1000mm(9) 实际轴间距安装时所需最少轴间距张紧或补偿伸长所需最大轴间距(10) 小带轮包角符合要求。(11) 单根V带所传递的额定功率 是、载荷平稳时,特定基准长度的单根V带基本额定功率。根据带型和查机械设计手册14表A型V带额定功率得=0.27kW。(12) 传动比i1时的额定功率增量根据带型、i和查表A型V带额定功率得。(13) V带根数(2.6)式中,为小带轮包角修正系数,根据小带轮包角查机械设计手册14表小带轮包角修正系数得=0.91,为带长修正系数,根据带长查机械设计手册14表普通V带带长修正系数得=0.96,代入(2.6)中得:因此需要三根带。(14) 单根V带的预紧力(2.7)式中,m为V带每米长的质量,查机械设计手册14表V带每米长的质量得m=0.06kg/m-1,代入(2.5)式中得:(15) 作用在轴上的力2.2.4 小带轮的结构设计设计带轮应满足以下要求:质量小,结构工艺性好;无过大的结构内应力;质量均匀,转速高时要进过动平衡;轮槽工作面要精细加工;以减少带的磨损;各槽的尺寸和角度应保持一定的精度,以使载荷分布均匀。(1) 首先选择带轮的结构形式。V带轮典型的结构形式有实心、辐板(或孔板)和椭圆轮辐三种。由于带轮基准直径较小,选择实心式。(2) 由于前面所选带型为A型,与之相配的带轮轮槽也为A型,图2-4是查机械设计手册14表V带轮轮缘尺寸所得的小带轮结构示意图,其尺寸如下:图 2-4 小带轮结构示意图基准宽度=11mm;基准线上槽深=2.7mm;基准线上槽深=11mm;槽间距=150.3mm;第一槽对称面至端面的最小距离=9mm,由于电机轴键槽长22mm,选择;槽间距累积极限偏差0.6mm;带轮宽;毂长,当B1.5d时,取L=B,因此L=50mm;外径;轮槽角;轮槽角的极限偏差0.5。2.2.5 大带轮的结构设计大带轮的设计与小带轮类似,可确定其部分尺寸如下: 基准宽度=8.5mm;基准线上槽深=2mm;基准线上槽深=7mm;槽间距=150.3mm;第一槽对称面至端面的最小距离=7mm,取;槽间距累积极限偏差0.6mm;带轮宽;毂长,当B0.07d, d2-3=d6-7=25mm。考虑此处轴径,由轴承产品目录中初步选定整体有衬正滑动轴承,其尺寸为 dDB=303850, 所以d3-4= d5-6=30mm。查机械设计手册整体有衬正滑动轴承的轴肩高为4mm,所以 d4-5=38 mm由刀盘的尺寸和从动轮的尺寸确定 L1-2=45mm ,L7-8=20mm。由轴承的尺寸,可以确定 L3-4=L5-6=50mm。根据轴承的装拆及便于对轴承添加润滑剂的要求,取L2-3=L6-7=45mm。根据轴的总体尺寸,取 L4-5=105mm。2.3.5 轴承的设计由轴的结构尺寸确定,安装轴承的轴直径是30mm。查机械设计手册14 表2-3选取安装简单的整体有衬正滑动轴承。表2-3整体有衬正滑动轴承型号dDRBbLL1HhH1d1d2C质量/kgHZ030303830504015011070352018.5M1011.51.7其主要外形安装尺寸如图2-7图2.7 整体有衬正滑动轴承2.3.6 主轴支承方案的确定由于机床要求结构简单且受力不大,因此采用前后两端进行轴向定位,常用的轴承配置方式有两种:两端固定支撑和一端固定一端游动支撑。两端固定支撑指每个支撑只固定轴承内、外圈相对的一个侧面,两个支撑组合起来限制轴的双向移动,这种固定方式结构简单,安装调整容易,适于温度变化不大和较短轴的固定。一端固定一端游动支撑指一端支撑的轴承内外圈两侧均固定,从而限制了轴的双向移动,另一端内圈两侧固定,防止脱落,这种固定方式结构比较复杂,但工作稳定性好,适应于对工作温度变化较大的长轴的固定。主轴前端装有圆盘刀具,主轴的回转精度直接影响到圆盘刀具与蔬菜之间切割压力的大小,后端装有大V带轮。因此采用固定方式简单,安装调整容易的两端固定。图2-7是主轴部件的结构示意图,大带轮周向固定采用键,轴向固定一端采用六角螺栓和垫圈固定,另一端采用轴肩固定。主轴周向固定采用轴肩固定,轴向固定采用一对整体有衬正滑动轴承。图2.7主轴部件结构示意图2.3.7 主轴的校核计算本计算是经过轴的初步设计和轴的结构确定后的校核计算。选取轴的材料为 45 号钢,调质处理。根据机械设计14,已经算出轴的最小直径为 20 mm,扭矩为 14.65 N.m。最大摩擦力F=19.2N,如图2-8所示,方向与蔬菜位置处圆盘刀具运动方向相反,将圆盘刀具所受摩擦力向轴心简化,如图2-9所示,合力为:FX=0蔬菜作用于圆盘刀具上的总力矩T=14.65Nm;图2-8圆盘刀具所受摩擦力示意图图2-9圆盘刀具受力图据本章2.2.3节计算可知,带轮作用在主轴上的径向力Q=277.3N,图2-10是主轴受力示意图。O点为圆盘刀具作用于主轴上的点,A点和B点为两轴承作用于主轴上的点,C点为大带轮作用于主轴上的点,首先求出A点和B点出各个方向上的作用点,然后画出各个平面内的主轴弯矩图,将弯矩合成,接着画出扭矩图,最后将弯矩和扭矩合成得出计算弯矩来进行校核。图2-10主轴受力示意图(1) X-Y平面内受力分析图2-11是X-Y平面内的受力图,其中,L1=145mm,L2=105mm,L3=115mm。图2-11 X-Y平面内受力图受力计算式为:(2.9)由式(2.7)可得:,图2-12是X-Y平面内的弯矩图。图2-12 X-Y平面内弯矩图 (2) Y-Z平面内图2-13是Y-Z平面内的受力图,其中,Q=227.3N,L1=150mm,L2=105mm,L3=115mm。图2-13 Y-Z平面内受力图受力计算式为:(2.10)由式(2.8)可得:,图2-14是Y-Z平面内的弯矩图。图2-14 Y-Z平面内弯矩图(3) 合成弯矩A点和B点处为危险截面,求出A点和B点的合成弯矩:图2-15是其合成弯矩图,图2-16是其扭矩图。图2-15 合成弯矩图 图2-16 扭矩图(4) 按弯扭组合强度条件校核轴的强度通常只校核轴上承受最大弯矩和转矩的截面(即危险截面B处)的强度。其校核公式为:(2.11)式中, 是考虑扭矩和弯矩的作用性质不同而引人的校正系数,取=0.6(单向传动,考虑启动、停车的影响,转矩按脉动循环变化),代入式(2.11)中得:抗弯截面模量:B处的弯曲强度:故设计的轴有足够的强度,并有一定的裕度。2.3.8 轴承的校核整体式有衬正滑动轴承是一种常见的径向滑动轴承。最常用的轴承座材料为铸铁。轴承座用螺栓与机座联接,顶部设有装油杯的螺纹孔。轴承孔内压入用减摩材料哦轴套,轴套上开有油孔,并在内表面上开油沟以输送润滑油。整体式轴承构造简单,常用于低速、载荷不大的间歇工作的机器上。由上述可知,选择整体式有衬正滑动轴承,先对其校核。因该轴承受Fr和Fa的作用,必须求出当量动载荷P。计算时用到的径向系数X、轴向系数Y要根据Fa/Cor指查取,而Cor是轴承的径向额定静载荷,在轴承号未选出前暂时不知道,故用试算法。根据机械设计手册,暂取Fa/Cor=0.17,则e=0.5.因Fa=115.2N,Fr=14.29N,则Fa/Fr=8.06e,由机械设计手册查得X=0.44,Y=1.4。由公式: (2.11)得:计算所需径向基本额定动载荷值,由公式: (2.12)fp=1.2(查机械设计手册得),ft=1(查机械设计手册得),Lh是使用寿命,为12000h所以:CR=38953800故整体有衬正滑动轴承适用。2.4 键的选择和校核2.4.1 键的选择均为一般联接,可选用普通平键中的圆头普通平键。安装刀盘处键的选择:此处轴的直径d1=20 mm,查机械设计手册14表得键的截面尺寸为:宽度b=6mm,高度h=6mm,取键长L=14mm.与皮带轮联接的键的选择:此处轴径为d2=20 mm,同理选用键的宽度b=8 mm,高度h=7mm,取键长L=18mm.2.4.2 键的校核键、轴的材料都是钢,键采用静联接,冲击轻微。查机械设计手册得许用挤压应力P=120150Mpa,取P=135Mpa。键1的工作长度L1=L-b=14-6=8mm,键与刀盘的接触高度k=0.5h=3mm查机械设计手册由公式: (2.13)得出P为116Mpa小于P所以键1的强度合适。键2的工作长度L2=L-b=18-8=10mm,键与皮带轮的接触高度k=0.5h=3.5mm (2.13)得出P为Mpa小于P所以键2的强度合适。T传动的转矩 Nmk键与轮毂键槽的接触高度l键的工作长度 mmd轴的直径2.5 刀具的设计2.5.1 新月型刀具新月型刀具主要用于切削软的物料,如食品,叶类蔬菜等。新月形刀具又分为单刀和双刀两种。如图(2-17)在物料输送速度一定的条件下,用双刀具时的物料切片厚度为采用单刀时的切片厚度的一半。在本机上,当要求切片厚度变为1mm时,只能采用双刀进行切削。单刀用于加工茎类,叶类,长细状的物料。加工尺寸范围较大,加工长度为230mm。可以切片,也可以切丝。双刀也用于加工茎类,叶类,长细状的物料。加工长度为116mm。也可以切片,切丝。(a) 单 刀 (b) 双 刀图2-17 新月型刀具2.5.2 圆盘刀具主要应用于切削物料形状不规则,短而硬的物料,如土豆,洋葱等。因为刀片时按在圆盘上,所以一方面增加了刀具的刚性,另一方面刀盘可以挡住刀具不切削时的物料送进而不致使物料掉下来(当物料短时),以便保证物料的切削厚度的均匀性和可靠性。圆盘刀具同样又分为单刀圆盘刀和双刀圆盘刀。如图(2-18)它们之间的切削厚度的关系与新月形刀具的单刀和双刀的切削厚度关系相同。采用圆盘刀具的一个重要的特点是它能够调整切片厚度。它可以根据刀片厚度的要求,在圆盘刀架安装刀具的表面和刀具定位面之间加入一个可调厚度的垫片来调整刀具的高度,从而可以改变切削厚度。虽然刀片为不锈钢材质,但是要在刀具使用之后用水洗净,烘干,涂油保管起来,不要与其它硬件放在一起,以免碰坏刀片的刀刃。图2-18 圆盘刀具2.5.3 刀具的最后设计根据本章2.5.1和2.5.3对两种刀具的介绍,我决定定在圆盘刀具的基础上进行改进。考虑到本次设计的要求,因此我设计在圆盘上安装3把刀片,来进行对蔬菜的切割,即在圆盘旋转一周的时间内,刀片对蔬菜切割3次。刀片的尺寸为:长取95mm,宽取40mm。用铆钉将刀片铆上去。铆钉的大小选取:采用沉头的型式,L=11mm,d=6mm。图2-19 刀具2.5.4 料斗的设计入料斗是保证进料顺利,同时起定力刃的作用,根据本机构的整体特点,入料斗设计成倾斜的矩形状,这样物料可以出重力自动下滑,入料斗和叶轮之间的距离不能太大或太小,必须保证切片的厚度,所以设计入料斗与刀盘之间的距离为 100 m 左右。现考虑如何让蔬菜进入料斗后能顺利下滑,来完成切割工序,首先查表得到物料与物料之间的摩擦系数为 0.4, 在分析茎块在料斗中的受力情况。要让蔬菜能顺利下滑,必须要求向 Fn 向 x 轴的投影在 x 轴的正方向上, 那样蔬菜才能顺利下滑,那么就必须要求,斜坡角度的确定过程如下: FR= FN+F1 (2.14) 要想让茎块能顺利下滑的话,那么必须 Gsin(-)0,也就是说时茎块就能顺利下滑,f=tg=0.4,得到=21.8,而,所以取=45,也就是说料斗的倾斜角度=45o。图2.20 料斗第3章 机架的设计3.1 机架设计要求机架起到在机器中支承或容纳零、部件的作用,机架的设计主要应保证以下三点:1.足够的强度和刚度;2.形状简单,便于制造;3.便于在机架上安装附件等。绝定机架工作能力的主要准则是刚度。在离心式切片机的中刚度决定着切片机的生产效率和切削精度。强度是评定重载机架工作性能的基本准则。机架的强度应根据机器在运转过程中可能发生最大载荷或安全装置所能传递的最大载荷来校核其静强度。此外还要校核其疲劳强度。机架的强度和刚度都需要从静态和动态两方面来考虑。动刚度是衡量机架抗震能力的指标,而提高机架抗振能力应从提高机架构件的静刚度,控制固有频率,加大阻尼等方面着手。机架受压结构及受压弯结构都存在失稳问题。有些构件制成薄壁腹式也存在局部失稳。稳定性是保证机架正常工作的基本条件。必须加以校核。为了满足稳定切片和切削效率的要求,本设计的离心式切片机在功能上应该完成以下几点要求:1.在满足强度和刚度的前提下,机架的重量应要求轻、成本低。2.抗振性好。3.噪声小。4.温度场分布合理,热变形对精度的影响小。5.结构设计合理,工艺性良好,便于铸造、焊接和机械加工。6.结构便于安装、调整及修理。7.导轨面受力合理、耐磨性良好。8.造型好。3.2 机架材料的选用及壁厚选择铸造机架常用材料:1.铸铁:铸铁流动性好,体收缩和线收缩小,容易获得形状复杂的铸件。铸铁的内摩擦大、阻尼作用强,故动态刚性好。另外还有切削性能好、价格便宜和易于大量生产等优点。铸铁主要 有灰铸铁、球墨铸铁。2.铸造碳钢铸钢的弹性模量大,强度也比铸铁高,故用于受力较大的机架。由于钢水流动性差,在铸型中凝固冷却时体收缩和线收缩都较大,故不宜设计复杂形状的铸件。3.铸造铝合金铝合金密度小、重量轻,通过热处理强化,具有足够高的强度、较好的塑性,良好的韧性。材料的选用,主要是根据机架的使用要求。本设计中的离心式切片机的形状较复杂。铸铁的铸造性能好、价廉和吸振能力强,应用也最广。焊接机架具有制造周期短、重量轻和成本低等优点。由于本设计的机架结构较为复杂,为了满足支撑其它各零件的要求,本离心式切片机机架各零件零件采用 HT200,整体选择焊接的方式。4.壁厚选择机架零件的外廓尺寸一定时,因而在满足强度、刚度、振动稳定性等条件下,应尽量选用最小的壁厚。3.3 机架整体设计机架整体应起到固定及连接各零件的作用。机架结构如下图3-1。1-料斗 2-整体有衬正滑动轴承 3-轴 4-电动机 5-螺栓 6-小V带轮 7-键 8-垫圈 9-键 10-V带 11-螺栓 12-螺栓 13-大V带轮 14-圆盘刀具图3-1 切菜机机架图参 考 文 献1 章军, 张念龙. 高效通用型蔬菜加工机的研制J. 食品与机械, 2002, 05: 27-38.2 任显云, 侯明亮, 王益强. 多功能块根状蔬菜加工机的研制J. 青岛农业大学学报(自然科学版), 2008, 01: 61-63.3 王荣满. 延长切粒机动刀使用寿命J. 聚酯工业, 2005, 01: 58-59.4 张大可, 张冬化. 多功能食品加工机的选与用J. 河南科技, 2002, 18: 29.5 刘小龙, 刘晨, 伊明买买提, 梁勤安, 穆晓路. 6LQT-550型离心式饲用甜菜切丝(片)机J. 新疆农机化, 2004, 04: 21-25.6 刘小龙, 刘晨, 伊明买买提, 梁勤安, 穆晓路. 6LQT-550型离心式饲用甜菜切丝(片)机J. 新疆农机化, 2004, 04: 21-25.7 鲍乐祥. YQC1000B型直线式多用切菜机的电气智能化改进D. 山东建筑大学,2011, 04. 8 苟爱梅. 甜菜切顶机的研究与设计D. 新疆职业大学学报, 2012, 04: 75-77.9 周峻雄. 新型切菜机和电搅机J. 食品与机械, 1992, 01: 36.10 王琛, 王进华, 陈佰杰, 郭静, 李建乐. 甜菜打缨切顶机的研究J. 农机化研究, 2013, 03: 157-159.11 陆宏文. 圆盘式切菜机J. 上海调味品, 1990, 07: 19-20.12 鲍乐祥, 郑明刚, 姜志方, 朱晓会. 基于PLC与MCGS的切菜机控制系统J. 机电产品开发与创新, 2011, 01: 169-170.13 冯永刚. QC-5001型多用切菜机的研制与开发J,机械设计,2013, 01: 85-88.14 王文斌等. 机械设计手册. 机械工业出版社. 北京: 2004.15 战晓林, 陶学恒, 李玉光. 食品机械中自动切割装置的研发J. 包装与食品机械, 2011, 02: 47-50.16 M. Entacher, G. Winter, T. Bumberger, K. Decker, I. Godor, R. Galler Glancey. Cutter force measurement on tunnel boring machines-System designJ, Tunnelling and Underground Space Technology incorporating Trenchless Technology Research, 2007, 04: 97-106.17 S Talapatra. Implementation of Product Design Tools for the Development of an Automated Vegetable ChopperJ. Khulna University of Engineering & Technology, 2014, 01: 1-7.18 N. Berme, D. K. Wright. Stress distribution in disk-type pipe-cutter wheelsJ. Experimental Mechanics, 1975, 10: 369-374.19 Young S J, Parfitt CH, Newell R F, Spittler TD. Homogeneity of fruits and vegetables comminuted in a vertical cutter mixerJ, Journal of AOAC International, 1996, 04: 976-980.致 谢经过16周的忙碌和工作,本次毕业论文设计已经接近尾声,作为一个本科生的毕业论文,由于经验的匮乏,难免有许多考虑不周全的地方,如果没有导师的督促指导,以及一起工作的同学们的支持,想要完成这个设计是难以想象的。在论文写作过程中,得到了XXX老师的亲切关怀和耐心的指导。他严肃的科学态度,严谨的治学精神,精益求精的工作作风,深深地感染和激励着我。从课题的选择到项目的最终完成,X老师都始终给予我细心的指导和不懈的支持。多少个日日夜夜,宋老师不仅在学业上给我以精心指导,同时还在思想、生活上给我以无微不至的关怀,除了敬佩宋金鹏老师的专业水平外,他的治学严谨和科学研究的精神也是我永远学习的榜样,并将积极影响我今后的学习和工作。在此谨向宋老师致以诚挚的谢意和崇高的敬意。 在论文即将完成之际,我的心情无法平静,从开始进入课题到论文的顺利完成,有多少可敬的师长、同学、朋友给了我无言的帮助,在这里请接受我诚挚的谢意!附 录1Implementation of Product Design Tools for the Development of an Automated Vegetable ChopperSubrata Talapatra, Md. Shakil, Pritom Kumar Mondal, Md. Saiful IslamDepartment of Industrial Engineering & Management (IEM),Khulna University of Engineering & Technology (KUET), Khulna, BangladeshEmail: sub_ksy, shakil.anowar, pritom.ipe08, saifuliemReceived October 26, 2013; revised November 26, 2013; accepted December 3, 2013Copyright 2014 Subrata Talapatra et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In accor- dance of the Creative Commons Attribution License all Copyrights 2014 are reserved for SCIRP and the owner of the intellectual property Subrata Talapatra et al. All Copyright 2014 are guarded by law and by SCIRP as a guardian.ABSTRACTIn the era of industrialization, automatic machines become an integral part of human life. These machines help to reduce the time needed to do a specific task. Nowadays, human life becomes more competitive and faster than the previous. Automation brought about by technology has saved human effort and time to a large extent. Slicing vegetables are a risky and time-consuming task in our busy life. This project is aimed at solving above stated problems by introducing a special product named Automatic Vegetable Chopper. This chopper is mainly de- signed to reduce human effort and make the job of chopping vegetables much easier and faster. Its main features are fully automated, easily portable, less power consumption and changeable stainless, sharp blade, etc. This product is designed and established by following a structured product design process and with the help of a board of design engineers. Product planning, customer needs identifying, product specification, concept screen- ing, concept scoring and bill of materials are tools that mainly used to accomplish this task. Finally, this paper also suggests various techniques and opportunities of product planning in manufacturing industries as future recommendations.KEYWORDSAutomatic Machine; Chopper; ProductPlanning; Bill of Materials1.IntroductionProduct design is considered to be the most difficult, sensitive and critical in creating products 1. It greatly influences the cost, robustness, manufacturability and development time of the final products 2. As a rule of thumb, the cost of engineering changes increases by ten times when changes are made in a later stage. Product planning, customer needs identifying, product specifica- tion, concept screening, concept scoring and bill of mate- rials are the basic tools for the development and design of a product. Designers use these concepts for the develop- ment of a product. This stage also includes comparing the relative strengths and weaknesses of the product, and determining concepts for further investigation, testing or development.These phases significantly affect whether the final de- sign will be exemplary, resulting in higher profits, or will have fundamental flaws that often require costly recalls. Many designers are challenged during this process by having to make many decisions with limited information. Many design methods have been developed to assist de- signers in making the correct decisions during the con- cept selection phase 3, including Pughs concept scor- ing 4, analytic hierarchy process (AHP), fuzzy set 5, fuzzy AHP method 6, flexible design concept selection 7, hypothetical equivalents and in-equivalents method 8, and quality function deployment (QFD) 9. Among these methods, the product planning, customer needs iden- tifying, product specification, concept screening, concept scoring and bill of materials steps are most commonly used in industry 10. In essence, concept scoring and the AHP method have fundamentally the same methodolo- gies 11. The concept scoring method is a numerically weighted Pugh method, while AHP is a more mathematic version of concept scoring that minimizes personal bias during the weighting and scoring. According to Yeo et al., concept scoring and AHP have been found to provide similar results, as long as the differentiation between the alternatives is sufficiently large. Furthermore, the sim- plest and most commonly used form of concept selection methods has also been found to be most applicable to support the fuzzy nature of concept selection 12. How- ever, limitations, such as uncertainty and inability to pro- vide the information on the compatibility between design concepts, remain as challenges for the concept selection method 13. According to Hu and Pieprzak, the funda- mental set of principles that define good axiomatic de- sign practice can help to facilitate the generation of good design 13.This paper illustrates the design and development of an Automatic Vegetable Chopper. The product is de- signed and developed with the help of various product design tools like product planning, customer needs iden- tifying, product specification, concept screening, concept scoring and bill of materials, etc. After carefully imple- mentation of those tools, final product is designed and developed which is cheaper than the available in market.2.Available FeaturesAutomatic Vegetable Chopper is technically advanced, use in cutting different kinds of vegetables, fruits, and other food items. This chopper has the facility of auto- matic feeding and discharge which in turn saves time. These machines have tubular feed-throat that is use to cut different long shaped vegetables. Before this work auto- matic chopper or slicer available on the market was little bit larger and noisy. In that case this product will add a new perspective in household chores like chopping veg- etables as well as it carries a sign of modern lifestyle and smartness. Following features are available in this prod- uct:1. Changeable stainless, sharp blade.2. Bakelite plastic body to resist fire caused by short- circuits.3. Conveyer belt made from food grade rubber.4. Fully automated.5. Easily portable.6. Less power consumption.7. Rechargeable battery.3.Components for the DevelopmentAutomatic Vegetable Chopper is technically advanced and it consists of shafts, discs, blades and bushings are making using stainless steel that is easy to clean and hence hygienic. Commercial this vegetable cuter is made from aluminum body. Stainless steel slicing, grating, di-cing, cubing, striping, figure chips making blades fitted on aluminum disc. Stainless steel shaft is drive with help of v belt and suitable four pole totally enclosed fan cooled single or three phase squirrel cage electric motor. Basic components are:1. Body (Bakelite Plastic)2. Cutter Blade (Stainless Steel)3. Pulley4. Crankshaft Mechanism5. D.C. Motor6. Conveyor BeltThese components are designed in AutoCAD 2007; Designed components are represented in the following Figure 1.Standard accessories of Automatic vegetable chopper machine:1) Suitable four pole totally enclosed fan cooled single or three phase squirrel cage electric motor is supplied with vegetable cutter.2) Five blades (3 different size e disc for slicing, 1 z discs for grating, 1 d discs for cubes).3) One number aluminum discharge plate, one auto feeder and one manual tubular feed-throat.Figure 1. Designed components for the automatic vegetable chopper in AutoCAD 2007.4. Product PlanningProduct planning is a process of discussing and defining features of a product before its development. There are a number of phases to product planning, including gather- ing input, refining ideas, approving and designating projects and tasks, refining market requirements and beginning product development. Product planning is important for a number of reasons. One of the earliest stages of product planning is gathering input about a new product idea. All perspectives are important, but pay close attention to customer feedback. A survey to ask existing customers about features they want and price would pay, as well as any other details specific of product.The mission of Automatic vegetable chopper deve-opment is to be the leader in the Kitchen accessories market, providing easy chopping solutions that accelerate cooking activity. A key element of Automatic vegetable choppers competitive strategy is to exploit technological innovation in a rapidly changing market. Product plan identifies the portfolio of products to be developed by the organization and the timing of their introduction to the market. The planning process considered product devel- opment opportunities identified by many sources, includ- ing suggestions from marketing, research, customers, cur- rent product development teams, and benchmarking of competitors. The product plan is regularly updated to re- flect changes in the competitive environment, changes in the technology and the information of the success to ex- isting product.There are four types of product development process:1) New product platforms2) Derivatives of existing product platforms3) Incremental improvements to existing products4) Fundamentally new productsAutomatic vegetable chopper is under the third cate- gory that is incremental improvements to existing prod- ucts. While developing Automatic vegetable chopper these points are focused: low cost, ease of dis-assemble and re-assemble, safety issues, efficiency, available machine- ries, ease of maintenance and carrying. For the develop- ment of a product plan and project mission statements, there are four possible steps which Automatic vegetable chopper development team follows:4.1. Identify OpportunitiesFor the design and development of the product, ideas have been gathered from the sources: Sales personnel from house-hold utensils stores of various markets (New market, Railway market, Jolil-tower), Technology de- velopment organizations (IEEE-KUET, HACKS-KUET), Product development team, Current customers (house- wives, bachelors, hostel-girls) Here some places and organization mentioned that is from Bangladesh.4.2. Evaluate and Prioritize ProjectsThere are several stages are followed for the design and development of the “Automatic vegetable chopper”. These stages are classed as Competitive strategy and Market segmentation.Competitive strategy:1) Technology leadership: To implement this strategy “Automatic vegetable chopper” here emphasized on some advanced technology featured equipment e.g. specially designed conveyor belt, stainless cutting blade, speed con- troller and self-switching.2) Customer focus: Automatic vegetable chopper de- velopment is focused on customers changing needs and preferences. The features of customer interest are imple-mented in this product (rapid and easy cutting, greater safety)3) Imitative: A Japanese company named “YOUKU” has made great improvement to vegetable chopper. Au- tomatic vegetable chopper development has nearly fol- lowed their technology.Market segmentation: Automatic vegetable chopper de- velopment team has segmented the market into the fol- lowing two categories.1) Large: It is for restaurants and hotels;2) Small: it is for house-hold usages.S-Curve Framework for market segmentation:Usually the S-curve is represented in Figure 2 as the variation of performance in function of the time/effort. Probably that is the most used metric because it is also the easiest to collect data for. This fact does not imply, however, that performance is more accurate than the oth- er possible metrics, for instance the number of inventions, the level of the overall research, or the profitability asso- ciated with the innovation. In the innovation management field the S-Curve illustrates the introduction, growth and maturation of innovations as well as the technological cycles that most industries experience. In the early stages large amounts of money, effort and other resources are expended on the new technology but small performance improvements are observed. Then, as the knowledge about the technology accumulates, progress becomes more rapid. As soon as major technical obstacles are overcome and the innovation reaches a certain adoption level an exponential growth will take place.Figure 2. Technology S-curve for automatic vegetable chop- per.4.3. Allocating Resources and Plan timingAutomatic vegetable chopper development team has in- vested its maximum resources in efficient blade design, long lasting motors, non-corrosive materials for its body.This team projected the timing of the product on the ba-sis of technology readiness, market readiness and compe- tition.4.4. Complete Pre-Project PlanningProduct Vision Statement: Develop a fastest, safe, auto- matic vegetable chopper for chopping.Mission Statements showing in Table 1.5. Identifying Customer NeedsThe philosophy behind the method of identifying cus- tomer needs is to create a high quality information chan- nel that runs directly between customers in the target market and the developers of the product. This philoso- phy is built on the premise that those who directly con- trol the details of the including engineers and industrial designers must interact with customers and experience the using environment of the product. Without this direct experience technical trade-offs are not likely to be made correctly, innovative solutions to customer needs may never be discovered and the development may never de- velop a commitment to meet customer needs.Steps used for identifying customer needs are dis-cussed as follows.5.1. Gather Raw Data from Customers1) Interview: The product development team inter- viewed several persons about the product. Some of them are satisfied what they are using but most of them have expressed their problem and discussed what features should be a dded for the ease of the use.2) Focused Groups: The main group upon which the product development team is focused is women than the bachelor men because women do the kitchen course most of the time whereas the bachelor men have to do it for themselves since they have no female to do this.3) Observing the Product in Use: Watching customers use an existing product was intended can reveal impor- tant details about customer needs while using the present product that means various kinds of vegetable chopper the users often face a common problem which was cut- ting finger issues. It is also tiring and time consuming too.5.2. Interpret Raw Data in Terms of Customer NeedsCustomer needs are expressed as written statement and the results of interpreting the need underlying the raw data gathered from the customers. When the product de- velopment team surveyed they got the customer state- ment which they had turned into needs statements are given in Table 2.5.3. Organize the Needs into a HierarchyThe goal of this step is to organize the needs into a hie- rarchy list. The needs product development is found can be classified into three categories:1) Primary (Implementing automation, safety issues, re-assemble the knives etc.)2) Secondary (Easy to maintain, compactness etc.)3) Tertiary (The light source)Table 1. Product mission statement.Mission statementAutomatic Vegetable ChopperProduct descriptionA hand-held, power assisted chopper for chopping vegetable of desired shape and sizeBenefit propositionIt can be operated swiftly, Easily with less effort, Can be operated with safetyKey business goalsFirst product introduction in 2014. Serve as platform for all future automatic vegetable chopping products.Primary marketCapture 80% of product sales in primary market. House-hold uses.Secondary marketHotel, hostel uses.Assumptions and constraintsIncremental improvements to existing products. Hand-held Power assisted Recharge-able battery technology.Cutting blade manufactured in Germany.StakeholderConsumer, Retailer, Manufacturer, DistributorTable 2. Raw data of customer needs.Customer StatementsNeeds statementsI like lighter far more than match sticksImplement automationMost of the times I cut my fingersSafety issues should be taken in sightCan I use it while performing another work?Easy to operateI prefer smaller productProduct should be compacted and easy to maintainI cant work in darkA source of light is neededI need to cut in various sizesAble to re-assemble the knivesRust irritates me mostStainless steel for knives5.4. Establish the Relative Importance of the NeedsThe outcome of this step is a numerical importance wait- ing for a subset of the needs. There are two basic ap- proaches to the task:1) Relying on the consensus of development teams experience with customers.2) Basing the importance assessment on further cus- tomer surveys.6.Concept SelectionA matrix used to display how well different alternatives meet the list of product or process specifications or re- quirements. A concept selection matrix is organized by the requirements, and includes numerical values for tar- get specifications as well as observed specifications for a list of potential solutions. For the development of this product follows two-step method for concept selection. These two methods are: Concept screening & Concept scoring.6.1. Concept ScreeningThe purpose of Concept Screening is to narrow the num- ber of concepts quickly and improve the concepts. The concept screening includes the following six steps that is:1) Preparing the selection matrix2) Rating the concepts3) Ranking the concepts4) Combining and improve the concepts5) Selecting one or more concepts6) Reflect on the result and the processThese five steps are maintained for development of Automatic Vegetable Chopper in the following way:Step 1: For preparing the selection matrix Automatic Vegetable Chopper development team entered the con- cepts along the top of the matrix and the selection criteria is entered along the left hand side of the selection matrix. While choosing criteria Automatic Vegetable Chopper development team tried to give equal weight of various criteria and the unimportant criteria are neglected.Step 2: For rating the concepts Automatic Vegetable Chopper development team has used a relative score of “better than” (+), “same as” (0), and “worse than” () in each cell of matrix.Step 3: Here Automatic Vegetable Chopper develop-ment team has made the summation of all “better than”, “same as”, and “worse than” scores and entered the sum for each category in the lower rows of the matrix. After summation we rank orders the concepts and the concepts containing more pluses and fewer minuses ranked higher.Step 4: After rating and ranking the concepts Auto-matic Vegetable Chopper development team combined and improved some concepts. The combined and im- proved concepts are added in the matrix.Step 5: After completing all of the above activities Automatic Vegetable Chopper development team selected three concepts and concept scoring stage with its weighted selection criteria and more detailed rating used.6.2. Concept ScoringConcept scoring used for differentiate better resolution among competing concepts. Here “Automatic Vegetable Chopper” development team weights the relative impor- tance of the selection criteria and tried to focus on more refined comparisons with respect to each criterion. The concept screening includes the following five steps.1) Preparing the selection matrix2) Rating the concepts3) Ranking the concepts4) Combining and improve the concepts5) Selecting one or more conceptStep 1: In this step Automatic Vegetable Chopper de- velopment team prepared a matrix in a similar way and identified a reference point. Here added importance weights to the matrix for all criteria and these weights are deter- mined subjectively by all Automatic Vegetable Chopper development team members.Step 2: Here Automatic Vegetable Chopper develop- ment team rated all the concepts with respect to one ref- erence criteria a fine scale of 1 to 5 is used for their rat- ing.Step 3: After entering all the concepts after calculated the weighted scores by multiplying the raw scores by the criteria weights. The total score for each concept is the sum of the weighted scores. Automatic Vegetable Chop- per development team had tried to give each concept a rank corresponding to its total score.Step 4: After completing all the above steps the Auto- matic Vegetable Chopper development team takes the decision of combining some concepts and making some improvements.Step 5: After completing all of the above activities the Automatic Vegetable Chopper development team selected two concepts. The Automatic Vegetable Chopper devel- opment team selected the concepts by varying some weights and ratings.7. Bill of MaterialTable 3 shows the bill of material of automated vegeta- ble chopper.8. Break Even PointBreak-even point (BEP) is the point at which cost or ex- penses and revenue are equal: there is no net loss or gain, and one has “broken even.” A profit or a loss has not been made, although opportunity costs have been “paid,” and capital has received the risk-adjusted, expected re- turn. It is shown graphically as the point where the total revenue and total cost curves meet. In the linear case the break-even point is equal to the fixed costs divided by the contribution margin per unit, showing in Figure 3.So the cost of producing one unit of product will be 1165 TK (BDT) and the break-even point is originated in 511 units.9. Results and DiscussionConcept screening: The concept screening of Automatic Vegetable Chopper is set below showing in Table 4, performance rating in Table 5 and concept scoring inTable 6.10. ConclusionProduct is the life of a company. It can determine the success and failure of companies. A good product can make a company live in a long-term success based on a good design. Product design reflects the economy, tech- nology and culture of a company. The importance of product design is to be realized by managers. That is why more and more new-tech products appear in our life. The design and development of an automatic vegetable chopper gets perspectives on product design tools. This paper also shows the implementation of product planning, customer needs identifying, product specification, concept screening, concept scoring and bill of materials for the designing and development of an innovative and unique automatic vegetable chopper. Product design also em- phasizes on quality and performance of product accord- ing to customer specifications. This project focuses on the design and development of automatic vegetable chop- per with respect to combine art, science and technology to create usable and desirable products for consumers. In the end, the goal of project design is to build a product that will sell well, thus many of product designs focus on the user and human factors.Table 3. Bill of Material (BOM).ComponentsPurchased MaterialProcessing (machine + labor)Asseby (labor)Total Unit Variable CoastTotal Unit Fixed CoastTotal CoastStainless Cutter100100.0030.00130.00Conveyor Belt801.5081.5081.50Supporting Rod301.5031.5031.50Motor400400.00400.00Motor Speed Controller500.7550.7550.75Crank Shaft1002.001.50103.50103.50Plastic Frame1501.001.25152.25152.25Circuit Board3030.0030.00Rechargeable Battery5050.0050.00Electronic Switch and Regulator201.501.0022.5022.50Total Direct Cost10106.006.001022.0030.001052.0Overhead Charges503.0010.0050.00113.00Total Coast1165.0Table 4. Raw data of customer needs.Selection CriteriaA Conveyer beltB MotorC Stainless BladeD Rechargeable BatteryE Motor speed ControllerEase of handling0+0+Ease of use+Durability0+Ease of manufacture00Cost+0Ease of maintenance0+0+Portability00000Aesthetics+0+0Sum +sSum 0s Sum s233134422332341Net score13+2+1+2Rank45131Continue?NoNoYesYesYesConcept scoring: The relative performance ratings are .Table 5. Performance ratings.Relative PerformanceRatingMuch worse than reference1Worse than reference2Same as reference3Better than reference4Much better than reference5Table 6. Concept scoring of automatic vegetable chopper.C Stainless BladeD Rechargeable BatteryE Motor speed ControllerSelection criteriaWeightRatingWeighted scoreRatingWeighted scoreRatingWeighted scoreEase of handling15%30.4520.3040.6Ease of use10%40.440.420.2Portability5%20.130.1520.3EASW of manufacture12%30.3620.2430.36Cost22%20.4430.6630.66Ease ofmain tenance17% 40.6820.3420.34Durability9%50.4530.2740.36Aesthetics9%40.3620.1820.18Total score3.242.543Continue?DevelopNoDevelopFigure 3. Break even point analysis.REFERENCES1K. T. Ulrich and S. D. Eppinger, “Product Design and Development,” 2nd Edition, McGraw-Hill, New York, 2000.2J. Nevins and D. Whitney, “Concurrent Design of Prod- ucts and Processes,” McGraw-Hill, New York, 1989.3H. J. Wassenaar and W. Chen, “An Approach to Deci- sion-Based Design,” Proceedings of ASME DETC01, Pittsburgh, 9-12 September 2001.4 S. Pugh, “Total DesignIntegrated Methods for Success-ful Product Engineering,” Addison-Wesley, Boston, 1990.5D. L. Thurston and J. V. Carnahan, “Fuzzy Ratings and Utility Analysis in Preliminary Design Evaluation of Multiple Attributes,” Journal of Mechanical Design, Vol. 114, No. 4, 1992, pp. 648-658./10.1115/1.29170566S. H. Yeo, M. W. Mak and A. P. Balon, “Analysis of Decision-Making Methodologies for Desirability Score of Conceptual Design,” Journal of Engineering Design, Vol. 15, No. 2, 2004, pp. 195-208./10.1080/095448203100016421917A. M. King and S. Sivaloganathan, “Development of a Methodology for Concept Selection in Flexible Design Strategies,” Journal of Engineering Design, Vol. 10, No. 4, 1999, pp. 329-349./10.1080/0954482992612368T. K. See and K. Lewis, “Multi Attribute Decision Mak- ing Using Hypothetical Equivalents,” Proceedings of ASME DETC02, Montreal, 29 September-2 October 2002.9J. Hauser and D. Clausing, “The House of Quality,” Har- vard Business Review, May 1988, pp. 67-73.10 M. Salonen and M. Perttula, “Utilization of Concept Se- lection MethodsA Survey of Finnish Industry,” Pro- ceeding of IDETC/CIE, Long Beach, 24-28 September 2005, pp. 18-27.11 J. Wang, “Improved Engineering Design Concept Selec- tion Using Fuzzy Sets,” International Journal of Com- puter Integrated Manufacturing, Vol. 15, No. 1, 2002, pp.18-27. /10.1080/0951192011003499612 N. P. Suh, “The Principles of Design,” Oxford University Press, New York, 1990.13 M. Hu and J. Pieprzak, “Using Axiomatic Design to Im- prove Conceptual Design Robustness in Design for Six Sigma (DFSS) Methodology,” International Journal of Six Sigma and Competitive Advantage (IJSSCA), Vol. 1, No. 3, 2005, pp. 245-262./10.1504/IJSSCA.2005.008091附 录2产品设计工具的实施对自动化蔬菜切碎机的发展Subrata Talapatra,Md.Shakil,Pritom Kumar Mondal,Md.saiful Islam工业工程与管理(IEM),工程技术的库尔纳大学(KUET),库尔纳,孟加拉国摘要:在工业化时代,机器自动化成为人类生活中不可或缺的一部分。这些机器有助于缩短做特定任务的时间。如今,人类的生活变得更具竞争力,并比以前更快。通过技术带来的自动化在很大程度上节省了人力和时间。在我们繁忙的生活中切菜是一个危险且耗时的任务。本项目就是通过引入一个被命名为蔬菜切碎机的产品来解决上述问题。这个切碎机的主要目的是减少人力,使切菜这项工作变得更容易更快捷。此切碎机的主要特点是完全自动化,便于携带,耗电量少,而且还有可更换的锋利的不锈钢刀片等。本产品的设计和开发是通过产品结构的设计过程,并在设计工程师帮助下而完成的。产品规划,客户需求识别,产品规格,概念抉择,概念评分和材料清单是主要用来完成这项任务的工具。最后,本文还提出在制造业中的各种技术和产品规划作为对未来产品的建议。关键词:自动机;切碎机;产品规划;材料清单1. 引言 在产品的开发过程中,产品设计被认为是最困难的、最敏感的以及最重要的1。它极大地影响了最终产品的成本、耐用性、可制造性和开发时间2。作为一个经验法则,如果在后期对工程进行变更,其变更费用将增加十倍。产品规划、客户需求识别、产品规格、概念抉择、概念评分和材料清单是一个产品的开发和设计的基本工具。设计人员使用这些概念来进行产品的开发。此阶段还包括比较产品的相对优点和缺点,并确定概念作进一步调查,测试或开发。 这些阶段明显影响到最终的设计是否会成为模板,从而获得更高的利润,或者从这些阶段中发现一些需要高成本才能挽回的重要缺陷。很多设计师在这个过程中都面临挑战,因为他们要在有限的信息资源中进行许多抉择。现在已经有许多设计方法来帮助设计师在概念筛选这一阶段做出正确的决定3,包括普氏的概念评分4,层次分析法(AHP),模糊集法5,模糊层次分析法6,灵活设计理念的选择法7,假设当量法和当量法8和质量功能开展法(QFD)9。 在这些方法中,产品规划,客户需要识别,产品规格,概念抉择,概念评分和材料清单都是行业中最常用的10。从本质上讲,概念评分和层次分析法是基本相同的11。概念评分法是一个加权数值普氏法,而层次分析法,是一个比较精确版本的概念评分,并且在权衡和评分过程中最大限度地减少个人偏见。根据杨先生等人,概念评分和层析分析法已经被发现能提供相似的结果,只要替代品之间的差异性足够大。此外,最简单和最常用的概念抉择法这种形式被认为在支持概念抉择的模糊性方面是最合适的12。然而,局限性,例如不确定性和不能提供关于设计理念的兼容性信息,依然是概念抉择所面临的挑战13。据胡和Pieprzak,明确规定的一套良好的清晰的设计实践基本原则有助于良好的设计产品的传承13。 本文论述了自动蔬菜切碎机的设计和开发。该产品是在各种产品设计工具例如同类产品规划,客户需求识别,产品规格,概念抉择,概念评分和材料清单等的帮助下才得以设计并开发的。在谨慎使用这些工具后,产品的最终设计和开发比在市场上便宜得多。2. 可用功能 全自动蔬菜切碎机技术很先进,用来切割不同种类的蔬菜,水果还有其他食品。这个切碎机可以自动进料和排出从而节省时间。这些机器的管状进料口是用来切割不同形状和长度的蔬菜。在此之前,市场上供应的自动切碎机切片有点大而且声音比较吵。在这种情况下,该产品将在家庭琐事,例如切菜以及它承载现代生活方式和现代风格方面添加一个新的视角。这款产品有以下功能:1)可更换的不锈钢锋利刀片;2)胶木塑料机体可避免由于短路引起火灾;3)输送带由食品级橡胶制成;4)完全自动化;5)便于携带;6)耗电量少;7)充电电池。3. 开发组件 全自动蔬菜切碎机技术很先进,它的轴,盘,叶片和轴衬采用不锈钢材质,易于清洁,因此比较卫生。这种工业蔬菜连接器是由铝制车身制造的。不锈钢切片,光栅,小方块,魔方,条带,数字芯片安装在铝制圆盘刀片上。不锈钢轴是在V带和合适的单相或三相鼠笼式的四极全封闭风扇的电动机的帮助下驱动起来的。基本组件有:1)机身(胶木塑料);2)切断刀(不锈钢);3)滑轮;4)曲轴机制;5)直流电动机;6)输送带。在AutoCAD 2007中对这些组件进行设计,设计的组件如图1所示。图1 . 设计的零件在AutoCAD 2007中的自动蔬菜搅拌器 全自动蔬菜切碎机标准配件包括:1)合适的四极全封闭风扇冷却单相或三相鼠笼式电动机与切菜机提供;2)五叶片(3种不同规格的切片e盘,1个盘做为光栅盘,1个盘为立方体);3)一个数字铝排板,一个自动送纸器和一个手动管状进料口。4. 产品规划 产品规划是在产品开发之前所讨论并规定了产品特征的一个过程。产品规划有许多阶段,包括搜集输入、提炼思想、批准和指定的项目和任务、完善市场需求、并开始产品开发。产品规划是很重要的,这其中有很多原因。一个是产品规划的最初阶段是收集关于一个新的产品理念。所有的观点都是重要的,但对客户的反馈意见应密切关注。有一份调查是关于征求现有客户他们想要的功能和想要支付的价格,以及特定产品的其他具体细节。 自动蔬菜搅拌器开发的使命是成为厨房配件市场的领导者,提供简单的切碎方案,提高烹饪效率。自动蔬菜搅拌器的竞争战略的一个关键要素是要在瞬息万变的市场中开发创新技术。产品规划通过市场介绍的组织和时间开发来确定产品组合。产品规划过程认为产品开发的机遇由许多资源来决定,包括来自市场营销,研究,客户,目前的产品开发团队,和竞争对手的基准测试建议。该产品计划定期更新来反映在激烈竞争环境中的变化,并且反映现有的成功产品的技术和信息的变化。有四种类型的产品开发过程:1) 新产品平台;2) 现有的产品平台衍生工具;3) 对现有产品的增量改进;4) 全新的产品。 全自动蔬菜切碎器是根据第三类是对现有产品的增量改进。 在开发自动蔬菜切碎器时这些方面是应该关注的:低成本,便于显示组装和重新组装,安全问题,效率,可用机械,便于维修和携带。对于一个产品计划和项目使命的发展陈述,自动蔬菜搅拌器的开发团队应遵循如下四种可能的步骤:4.1. 找准机会 对于产品的设计和开发,想法收集的来源如下:由各种市场(新市场,铁路市场,Jolil塔),技术开发组织(IEEE-KUET,HACKS-的房屋持有用具专卖店销售人员KUET),产品研发团队,目前的消费者(家庭主妇,学士,宿舍女生)这里提到一些地方和企业都来自孟加拉国。4.2. 评估和优先发展项目 自动蔬菜切碎器的设计和开发要遵循以下几个步骤。 这些阶段被归类为竞争策略和市场细分。竞争策略:1) 技术领先:要实施“自动蔬菜切碎器”这一策略,这里强调了一些以先进的技术为特征的设备,例如专门设计的输送带,不锈钢切割刀片,速度控制器和自行切换器。2) 以客户为中心:全自动蔬菜切碎器开发的重点是客户不断变化的需求和喜好。 意向客户的特点在这款产品中实现(快速和容易切割,更高的安全性)。3) 仿写:日本一家公司名为“优酷”已经对蔬菜切碎器做了很大的改进。 全自动蔬菜切碎机的发展已经紧随着他们的技术。市场细分:全自动蔬菜搅拌器的开发团队已经把市场分为以下两类。1) 大的:用在饭店及酒店;2) 小的:用在家庭中。 S曲线框架市场细分:通常的S型曲线是在图2中表示,作为表现在时间/性能的函数变化。也许这是最常用的指标,因为它也最容易收集数据。这一事实并不意味着性能比其他可能的度量标准更加准确,比如发明的数目,总的研究水平,或者与创新相关的盈利能力。在创新管理领域的S曲线说明了创新的导入期,成长期和成熟以及技术周期,大多数行业的经验。在早期阶段,大量的金钱,精力和其他资源都花费在了新技术,但小的性能得到了改进。然后,关于该技术的知识积累,进展变得更加迅速。只要主要技术障碍是克服和创新达到一定水平采用指数增长会发生。自动蔬菜切碎机普通蔬菜切碎机蔬菜切碎机的性能今天时间图2 .技术S曲线自动蔬菜切碎机4.3. 资源分配和时间规划 全自动蔬菜切碎器的开发团队在高效的刀片设计上已经投入了最大资源,持久的电动机,以及其机身无腐蚀性的材料。该团队预计该产品的计时在技术准备,市场准备和竞争的基础上。4.4. 完善的售前项目规划产品愿景声明:开发速度最快,安全,自动的蔬菜切碎机切碎。使命陈述显示在表1。表1产品的使命宣言使命声明全自动蔬菜切碎机产品说明手持式,动力辅助切碎机,适用于有特定要求形状和大小的蔬菜优点操作迅速,轻松简单,安全主要商业目标首次的产品介绍是在2014年。为未来所有的自动蔬菜切碎产品提供平台初级市场在初级市场拥有80的销售额。家居使用。二级市场酒店,旅馆使用。假设和约束条件逐步改进现有产品。手持式动力辅助充电式电池技术。切削刀片由德国制造受益者消费者,零售商,制造商,分销商全自动蔬菜切碎机5. 确定顾客需要 本公司确定客户需求的方法是创建一个目标市场客户与产品开发人员之间能够直接接触的高质量信息通道。这种方法建立的前提是那些直接掌控细节的工程师和工业设计师必须与客户互动并且要体验产品的使用环境。如果没有这种直接经验的技术权衡,就不可能根据客户的需求制定出正确的创新方案,也可能永远不会被发现这种创新方案,那么研发也可能永远不会满足客户的需求。 对确定客户需求的步骤进行了讨论如下。5.1. 从客户收集原始数据1)采访:该产品开发团队就这一产品采访了几个人。其中有些人对他们所使用的产品是满意的,但大多数人都表述了他们对产品的一些看法,并讨论为了便于使用应该添加哪些特性。2)重点团体:产品开发的团队针对的主要团体多集中于女性而非单身男性,因为大部分时间是女性在收拾厨房,而单身男人不得不自己做,是因为没有女性为他们做
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本文标题:小型多功能切菜机的设计【6张CAD图纸和说明书】
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