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无锡太湖学院
毕业设计(论文)
相关资料
题目: 饺子机及传动系统设计
信机 系 机械工程及自动化专业
学 号: 0923039
学生姓名:
指导教师: (职称:副教授 )
(职称: )
2013年5月25日
目 录
一、毕业设计(论文)开题报告
二、毕业设计(论文)外文资料翻译及原文
三、学生“毕业论文(论文)计划、进度、检查及落实表”
四、实习鉴定表
无锡太湖学院
毕业设计(论文)
开题报告
题目: 饺子机及传动系统设计
信机 系 机械工程及自动化 专业
学 号: 0923039
学生姓名:
指导教师: (职称:副教授 )
(职称: )
2012年11月25日
课题来源
自拟题目
科学依据(包括课题的科学意义;国内外研究概况、水平和发展趋势;应用前景等)
(1)课题科学意义
饺子食品机械的应用前景和发展现状 饺子食品在我国历史悠久,伴随着几千年的文明的发展已经成为我国食品文化中的代表,如饺子、包子、馄沌是主食的一部分;汤圆、月饼、粽子是传统节日中必不可缺的食物。如今,经济的迅速增长、人民生活水平的提高和生活节奏的加快,对食品行业提出了新的要求。而本人认为这些要求可以归纳为两大类: 其一是食品的质量:如食用口感、卫生状况、营养含量等。 其二便是食品供应的速度。 而解决这两个矛盾要求的办法便是实现食品生产的机械化和自动化, 通过机械动作可以极大程度的提高食品的生产率; 采用环保的机械材料和严格的密封技术可以很好的保证食品卫生;而合理的工艺编排更能改善食品的口感。
(2)饺子机的研究状况及其发展前景
目前国内外厂家在包馅夹馅食品机械化上的研究已经取得了一定的成果成功研发了饺子机、包子机、馄沌机、汤圆机、月饼机以及自动化程度更高的全自动万能包馅机。 因东西方饮食文化的差异, 目前国外包馅成型类机械主要为日本所生产,如日产的自动万能包馅机,其最大生产能力可达每小时 8000 个,且加工范围极广,能生产各式馒头、包子、饺子、夹馅饼干、寿司、等等近百种产品,采用可拆卸料斗能实现快速更换馅料,内置的无级变速调控装置可以实现皮和馅的任意配比。广泛用于各种带馅食品的加工。 而国内相关机械虽然在自动化和多功能方面较之日本产品还有一定的差距, 但是通过改革开放以后二十余年的发展亦取得了很大的进步。 以上海沪信饮料食品机械有限公司生产的水饺机为例:配备 1.1Kw 的电动机,生产效率达每小时 7000 个。已相当接近日产饺子机的生产水平。
每逢过时过节现做现卖饺子往往出现供不应求的现象。当然也有很多人选择在家里自己做, 却需要提前半天甚至一天进行准备,而包饺子的时候更是要叫上好几个亲朋过来帮忙方可。 因此如果能研究开发一种能够以机械动作代替人工劳动的机器, 那么除了可以节约大量的时间、降低饺子的生产成本、提高利润之外,更可以免除人们冬日里冒寒排队购物之苦,一举多得。饺子生产机的初步目标确定为能够实现饺子包馅成型工艺的机械化。 未来可在此基础上加以改进和扩展,以实现横纵两方向发展。即饺子生产全过程的无人干预自动化与多功能化。
研究内容
① 熟悉饺子机的工作原理与结构;
② 熟悉饺子机传动系统的布置与结构;
③ 熟练掌握传动系统的设计计算方法;
④ 掌握CAD的使用方法;
⑤ 能够熟练使用UG进行三维的画图设计。
拟采取的研究方法、技术路线、实验方案及可行性分析
(1)实验方案
对饺子机整体设计,拟定其传动部分的结构、转速等,使其能够半自动的进行加工。
(2)研究方法
①用CAD进行二维画图,对饺子机结构有个全面的了解。
② 对饺子的传动部分进行计算与结构设计,使其提供合适的动力。
研究计划及预期成果
研究计划:
2012年10月12日-2012年12月31日:按照任务书要求查阅论文相关参考资料,完成毕业设计开题报告书。
2013年1月1日-2013年1月27日:学习并翻译一篇与毕业设计相关的英文材料。
2013年1月28日-2013年3月3日:毕业实习。
2013年3月4日-2013年3月31日:饺子机传动系统计算和总体结构设计。
2013年4月1日-2013年4月14日:传动箱设计。
2013年4月15日-2013年4月28日:零件图及三维画图设计。
2013年4月29日-2013年5月21日:毕业论文撰写和修改工作。
预期成果:
达到预期的毕业设计要求,设计出的饺子机可以进行半自动加工,可以快速美观的加工出饺子,并且传动简单紧凑、满足工作要求。
特色或创新之处
① 饺子机可以无需手工进行制作。
② 饺子制作过程安全,方便,快速,可以批量生产。
③ 传动路线简单、紧凑,满足饺子加工的要求。
已具备的条件和尚需解决的问题
① 设计方案思路已经明确,已经具备机械设计能力和饺子机方面的知识。
② 进行结构设计的能力尚需加强。
指导教师意见
指导教师签名:
年 月 日
教研室(学科组、研究所)意见
教研室主任签名:
年 月 日
系意见
主管领导签名:
年 月 日
英文原文
wear 181-183 (1995) 868-875
Case Study
Theoretical and practical aspects of the wear of vane pumps
Part B. Analysis of wear behaviour in the Vickers vane pump
test
A. Kunz a, R. Gellrich b, G. Beckmann c, E. Broszeit a
a Institute of Material Science, Technical University Darmstadt, P.O. Box 11 1452, 64229 Darmstadt,Gcmb University for Technol08y, Economy and Social Science Zittau/Goditz, Facuky of Maihematics, P.O. Box 264, 02763 Zutau
cPetersiliensrr. 2d, 03044 Cottbus, Received 16 August 1994; accepted l November 1994
Abstract
The wear behaviour of the vane pump used in the standard method for indicating the wear characteristics of hydraulicfluids (ASTM D 2882/DIN 51 389) has been examined by comparison of the calculated wear and experimental data using alubricant without any additives. In addition to the test series according to DIN 51 389, temperature profiles from the pump have been analysed using the bulk temperatures of the contacting components and the temperature in the lubrication gap as input data for the wear calculation. Cartridges used in tests according to the Gennan standard have been examined extensively before and after each run to obtain input data for the mathematical model and to Jocate wear. An analysis of the :tluid properties and an investigation of the innuence of wear particles in the hydraulic circuit were performed. The experimental results were compared with the wear prediction, which was verified by the agreement in terms of load, temporal wear progress and local wear. Conclusions have been drawn with regard to the validity of the load assumptions and wear calculation, as well as to the limits of applicability of this method in the presence of additives.
Keywords: Vane pumps; Hydraulic fluids; Wear prediction; Vickers vane pump test
1. Introduction
Efforts to develop a mathematical tool for wearprediction will not be successful without considering wear and its phenomena. The task of Part B of this study is to describe the analysis of the wear behaviour in the tribo system investigated and how the knowledge achieved influences the calculations. Input data are derived from the measurement of mechanical and geometrical quantities, such as the hardness, stylus profilometry, fluid properties and contact radii. Thermal quantities are also essential for the modelling of lubrication. The calculations must be verified with wear data. Because the tribo system to be analysed is the vane pump employed in the Vickers vane pump test,which has been in use for about 40 years, several wear data can be used for comparison between calculated and measured wear results. These are the wear masses0043-1648/95/$09.50@ 1995 Elsevier Science S.A. All rights reserved SSDI 0043-1648(94)07087-3 after each tcst run, the progrcssion of wear over time and the local wear on the inner ring surface; in combination, these enable a comprehensive statement to be made on the validity of the mathematical model described in Part A.
2. Experiments
AlI Vickers vane pump tests described were run with the same fiuid. It is a reference oil of the German Rcscarch Association for Transmission Technique (FVA), and is a mineral oil without any additives (FVA3). Thus the disturbing influences of additives can be excluded.
2./.Input data for calculation
Fig. 1 lists the input and output quantities of the calculations. Most of the input parameters were derived surface profiles contact force and contact velocity dynamic viscosity contact radiihardness values Youngs moduli, Poisson numbersand lubrication gapspecific shear energy densities* pressure exponentc,f viscosity; tlubrication gap temperature
Rough surfuce ←→ shaar energy hypot ←→ elasto liubiction
↓
Wm=f(t)
Wf =f(ɑ)
Fig. 1. Input parameters and output quantities of the mathematicalmodel of Part A.
Fig. 2. Cartridge V 104 C: bushing, rotor, ring, bushing (abcwe),single vane, pin (below).experimentally from all the components involved beforeand after use in the vane pump tests. The mechanical components, which must be renewed for each test run,are shown in Fig. 2. Such a cartridge kit consists of a rotor, ring, 12 vanes, bushings and pin.
Stylus profilometry was performed on the inner surface of the ring and on the tips of two vanes of the cartridge before and after each test run. Earlier investigations have shown that ten parallel sections in the sliding direction on each body are sufficient to describe the surface topography in a statistically satisfactory manner as a two-dimensionalisotropic gaussianfield according to Ref. [1]. Only the high pass filtered components of the profile (sampling length, 1.5 mm; cut o五 0.25 mm) were used to determine the spectral moments mo, m2, m4 and the parameter of roughness a. According to the partition of the contact force into different loading zones, the topographic data of the new surfaces were used for zone IV (low level load, see Part A). For the other zones with higher contact forces, the profiles of the surfaces in the final condition were used, which corresponds to the appearance of the inner ring surface after the test runs.
The contact force and contact velocity were calculated with different fluid pressures and dynamic forces acting on the vanes, revolution number and ring radu, whereas the change in contact radius was documented with a profile projector. Because the ring radii are much larger thar) the radii of the vanes in the contact zone, the vanes can be assumed to be hertzian cylinders sliding
along a plane surface and the contact radii are simply the radii of the vane tips. Each vane tip was twice drawn up at magnifications of 100 : 1 and the contact radii and contact locations were measured with a stenciLMean values of the contact radii were transferred to the calculation, which is based (similar to the surfaceprofiles) on vanes in both conditions.
The Vickers hardness HVlO was measured on thering and three vanes of each cartridge. This hardnessleads to a better reproducibility than microhardness values, but due to the large indenter load, it couldonly be taken after the test runs. Therefore changes in hardness values could not be registered.
The Young's moduli, Poisson numbers and densities of the ring (AISI 52100) and vane materials (M2 reg C) are the first input parameters in the shear energy hypothesis and were obtained from the literature. The specific shear energy densities (see Part A) are materialspecific constants [2l.
The fluid properties (Fig. 1) were measured, derived from the literature or calculated. To obtain the dynamicviscosity, the densities and kinematic viscosities at 20,40 and 80 0C were measured. Because the fluid is a reference oil of FVA, the pressure exponent of the viscosity is given [3]. The temperature in the lubrication gap between the ring and vanes was approx:imated by measurements and calculations described below.
2.2. Temperature profiles
Temperature measurement was performed to obtain information on how a heatable tribometer must be controlled to simulate the wear behaviour of the vane pump. Therefore shortened test runs were carried out until temperatures were stabilized. These 10 h vane pump tests delivered the input data for the approximation of the lubrication gap temperature in the ring-vane contact, as well as additional wear masses to be compared with the calculated progressiort of wear in time. The sampling principles for acquiring the temperature profiles of the vane pump are illustrated in Fig. 3.
The temperature of the lubricant in the gap between the ring and vanes was estimated to be equal to or greater than the bulk temperature on the inner ring surface. Following the first main statement of thermodynamics, the heat flux Q mp into the components of the pump can be derived from with the fluid as the medium for energy transport.Qa,mp can only be transferred to the components shownin Fig. 2. For the same temperature differences and materials, this heat nUX can be divided into single component fluxes ac cording to the relation of masses. The derived flux Qring is the heat which flows in a certain time period in a radial direction through the ring. With the known temperatures on the outer ring surface, the bulk temperatures on the inner ring surface
can be calculated and transferred to the model of elastohydrodynamic lubrication.
All test runs with the Vickers vane pump V 104 C were performed on a test rig according to ASTM D2882/DIN 51 389, which is shown schematically in Fig.
4. These standards describe the procedure for testingthe anti-wear properties of hydraulic fiuids. To start the Vickers vane pump test according to the German standard, the system pressure must be raised in steps of 2 MPa every 10 min, beginning at 2 MPa, until a final pressure of 14 MPa is reached. At this stage, the fluid temperature measurcd bcfore the pump (see Fig.4) must be controlled to guarantee a kinematic viscosity of 13 mm2 S-i at the inlet for every :tluid tested. These conditions must be maintained until the test is aborted normally after 250 h by opening the bypass of the pressure control valve before the motor is stopped. By a comparison of the wear achieved on the ring and vanes with the upper wear limits, the anti-wear properties of the fluid tested can be derived.
For performing the tests safely with the fluid FVA3, it was preheated t0 40 0C and circulated in a pressurefree way. The damage which may occur during the critical first hour of the runs can be avoided using TiNcoated bushings [4]. For comparison with the results derived from computation, the wear produced in these runs must be documented as amounts, both locally and temporally.
The wear masses were derived from the weight differences of the ring and vanes before and after each run. They were obtained from a sequence of four 250 h test runs and tw0 10 h runs for temperature measurement. The local linear amount of wear was documented by the differences in the inner ring radii perdegree of revolution, which were measured by surface digitization along the inner ring surface at three different positions of the ring width before and after the tesi runs.
In earlier investigations [5], the wear progression over time of the vanes was measured under identical testing conditions, except for a lower fluid temperature. For this experiment, the radiotracer technique was used. Two vane tips in the set of 12 vanes of each cartridge were radiologically activated by bombardment with protons. A detector close to the pump body allowed thedecrease in radiological activity to be monitored continuously, which was found to be reciprocally proportional to the linear amount of vane wear as a function of time [5l. Due to the good tempering properties of the vane material (M2 reg C), with a specific secondary hardness maximum between 450 and 550 0C, the infiuence of the activation process at 220 0C on the wear
behaviour of the activated zone of the vane tips could be excluded.
Phyd+Pfric-Qcomp-Qfluid=0 (1)
Qfluid=mcfluid△Tfluid (2)
Fig. 4. Hydraulic circuit of the test rig.
3 result
lines the statistical reliability of surface modelling as a two-dimensional isotropic gaussian field. Although only the filtered profiles scanned in the sliding direction are shown, a distinct change in surface roughness is obvious. A good representation of the wear phenomena (see Part A) by the input data for the wear calculation derived from these profiles can be assumed.
The change in the vane tip shape over the testing period is documented in Part A. The hardness values for the rings and vanes varied from 743 t0 769 HVlO (rings) and from 778 t0 816 HVlO (vanes). In all cases, the vanes of one cartridge had higher hardness values than the ring, but these differences varied and had a large influence on the wear calculation (see Part A).
The measurement of the fiuid properties led, in combinat
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