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无轴搅拌机传动系统的设计【7张CAD图纸和说明书】

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摘 要

    本次毕业设计的题目为无轴搅拌机传动部件的设计。首先对传统的几种常见的搅拌机构进行分析、总结其工作原理及其存在的常见问题。了解目前对其存在的问题的常用解决方案。熟悉“无轴”搅拌理念，掌握无轴搅拌机的工作原理，然后将其与传统的搅拌机进行比较，分析其主要优点及可能存在的问题以及解决方案。

其次，这次设计的重点是对其传动部件的设计计算，我采用的是带轮加锥齿轮的减速机构，即利用了带轮的传动远距离传动、大传动比，又利用了锥齿轮传动可改变传动方向的优点。通过设计计算达到了即提高工作效率又能有效地节约能源的目的。


关键词： 无轴搅拌机 ；传动部件 ；搅拌机构


Abstract

The graduation project is the subject of non-transmission parts mixer shaft design. First of all, the traditional institutions in several common mixing analysis, concluding its work principle and the existence of the frequently asked questions. Understand the current problems of its common solutions. Familiar with the "non-axis" mixing the concept of master-axis mixer without the working principle, and the mixer with the traditional comparison, analysis of their main advantages and potential problems and solutions.

Secondly, this is designed to focus on the design of its drive components, I used the bevel gear pulley increases the speed, namely the use of long-distance transmission of drive pulley, the transmission ratio and the use of a bevel gear transmission can change the direction of the advantages of transmission. Achieved through the design of computing that can effectively improve the efficiency and energy savings.


Key words: No shaft mixer;Transmission parts ;Stir agencies


目 录

 摘 要 III

 Abstract IV

 目 录 V

 1 绪论 1

   1.1 无轴式搅拌机研究发展现状 1

   1.2 搅拌机的各种类型及特点 2

   1.3 无轴式搅拌机特点 3

   1.4 搅拌机的分析及设计任务 3

     1.4.1 搅拌机常见问题的原因分析 3

     1.4.2 无轴搅拌的理念 4

     1.4.3 基本设计任务 5

     1.4.4 毕业设计的目的 5

   1.5 课题研究背景及意义 5

     1.5.1 课题研究背景 5

     1.5.2 课题研究意义 5

 2 传动方案及电动机的选择 7

   2.1 传动方案的选择 7

   2.2 电动机选择 8

 3 传动比的计算与分配 9

   3.1 计算总传动比 9

   3.2 传动比的分配 9

 4 传动运动参数的计算 11

   4.1 各级转速 11

   4.2 各级的输入功率 11

   4.3 各级转矩 11

 5 V带轮传动的设计计算 13

   5.1 设计准则 13

   5.2 原始数据及设计内容 13

     5.2.1 原始数据： 13

     5.2.2 设计内容： 13

   5.3 设计步骤和方法 13

     5.3.1 确定计算功率 13

     5.3.2 选择带型 13

     5.3.3 确定带轮的基准直径和 13

     5.3.4 确定中心距和带轮的基准长度 14

     5.3.5 验算主动轮上的包角 14

     5.3.6 单根V带传递的额定功率 15

     5.3.7 确定带的根数Z 15

     5.3.8 确定带的预紧力 15

 6 V带轮设计 17

   6.1 V带轮的设计内容 17

   6.2 设计要求 17

   6.3 带轮材料的选择及结构形式 17

     6.3.1 材料的选择 17

     6.3.2 结构形式 17

   6.4 V带轮的轮槽 17

   6.5 V带轮传动的张紧 18

 7 锥齿轮传动的设计计算 19

   7.1. 选定精度等级，材料及齿数 19

     7.1.1齿轮精度等级的选择 19

     7.1.2 材料选择 19

     7.1.3 齿数选择 19

   7.2 按齿面接触强度设计 19

     7.2.1 确定公式内的各计算数值 20

     7.2.2 计算 20

   7.3 按齿根弯曲强度设计 21

     7.3.1 确定公式内的各计算数值 21

   7.4 几何尺寸计算 22

     7.4.1 计算分度圆直径 22

     7.4.2 锥距 22

     7.4.3 计算齿轮宽度 22

     7.4.4 锥齿轮的结构设计 22

 8 轴的设计计算 25

   8.1 I轴的设计计算（锥齿轮轴） 25

     8.1.1 材料 25

     8.1.2 初定轴的最小直径 25

     8.1.3 根据轴定位的要求确定轴的各段直径和长度 25

     8.1.4 小锥齿轮的受力分析 26

     8.1.5 键的校核 26

     8.1.6 I轴轴承的校核 26

     8.1.7 轴上载荷的计算 28

     8.1.8 按弯扭合成应力校核轴的强度 29

   8.2 II轴的设计计算 29

     8.2.1 材料 29

     8.2.2 初定最小直径 29

     8.2.3 联轴器的选择 29

     8.2.4 根据轴的定位要求，确定各段直径和长度 30

     8.2.5 大锥齿轮轴的受力分析 30

     8.2.6 键的校核 30

     8.2.7 轴承的校核 30

     8.2.8 轴上载荷的计算 32

     8.2.9 按弯扭合成应力校核轴的强度 33

 9 结论与展望 35

 致谢 37

 参考文献 39

1 绪论

1.1 无轴式搅拌机研究发展现状

改革开放35年以来，中国混凝土搅拌机市场从无到有、从小到大。目前，我国年产水泥混凝土约为15亿，搅拌机的年产量也居世界前列。相比较而言，我国具有的自主知识产权技术也很少。但随着商品混凝土的大力推广、工程建设施工的高效率化、高质量化和高效益化，推动了混凝土搅拌设备向高效率、高质量的方向不断发展，一些传统设备己经无法满足施工要求。

在现有的搅拌机的基础上，对新型搅拌设备的研究和开发，提高混凝土搅拌机的设计水平，同时带动相关技术的发展，创造一个良好的生产空间；对高效混凝土搅拌机的开发，推动搅拌及机事业性能的快速发展，生产出适应市场要求、具有高可靠性和较强竞争力的搅拌机。依据新的搅拌原理，采用理论探讨和试验分析相结合的办法，能方便解决大型双卧轴搅拌机存在的低效率问题，如果生产工业化成功应用，一定为研制具有自主知识产权的高效搅拌机做出重大贡献。

长期以来，国内外搅拌设备虽然种类很多，但他们的共同特点：有一根轴贯穿整个搅拌空间。“双螺旋轴搅拌机”是一种新型的“无轴”搅拌机，它具有双倍的径向进给料流，双倍的轴向进给料流，双倍的剪切力，使搅拌效率达到普通搅拌机的两倍，能耗更小。“双螺旋轴搅拌机”无水平的主轴，不会产生混凝土黏合中心轴并产生结块形成抱轴的现象，更适合于加工粘性强和添加有纤维的混凝土材料。

20世纪70年代未至80年代初，我国为了适应建筑业有关方面混凝土发展的需要，在引进国外搅拌机的基础上，研制出了10多种混凝土搅拌楼（站）。经过引进研究、自主开发生产等几个阶段，到本世纪初，我国搅拌机技术得到更大的发展，在产品型号和生产数量上，都达到了一定规模，出现了一批更具有自主知识产权的新产品，并开始形成了一个具有一定规模和竞争能力的产业。2006年，我国生产装机容量0.5～6的搅拌站2100多台，已成为搅拌设备的研究和生产大国。

自上世纪八十年代初已经开始研制JS系列双卧轴混凝土搅拌机，一直到现在，已研制出从JS35～JS6000系列搅拌机，一直处于国际领先水平，尤其从2000年开始采用UG等三维软件，对搅拌机研究进行优化设计，对搅拌设备进行了动力分析和受力分析，大大提高产品的可靠性，达到国际先进水平。这些搅拌机的研制，基本满足了我国混凝土发展的需求，但随着主机市场的不断发展，新型主机的需求越来越多。无轴式搅拌机在国外也处在研究发展阶段。



1.2搅拌机的各种类型及特点

目前使用的搅拌机就其原理而言，其基本上可分为自落式和强制式两大类。

自落式搅拌机有较长的历史，早在20世纪初，混凝土搅拌设备开始不断出现。50年代后，人们研发出反转出料式和倾翻出料式的双锥形搅拌机，同时，其他一些搅拌机，如裂筒式搅拌机等相继问世。运作时，拌筒绕着水平轴线旋转，加入搅拌筒内的物料，叶片将物料提升至一定高度，然后借助自重下落，这样不断的循环运动，达到搅拌的理想效果。自落式混凝土搅拌机的结构简单，一般以搅拌塑性混凝土为主。但自落式搅拌机已不符合国家的有关标准，属于淘汰产品，所以本文不作研究。

强制式搅拌机从20世纪50年代初兴起后，得到了迅速的发展和生产推广。最先出现的是圆盘立轴式强制混凝土搅拌机。这种搅拌机分为涡桨式和行星式两种。19世纪70年代后，随着轻骨料的出现，研制出了圆槽卧轴式强制搅拌机。 

实践证明，在上述混凝土搅拌设备的搅拌主机在工作中经常出现混凝土 “抱轴”现象。如果不及时停机清除，“抱轴”的混凝土会越来越多，将会引发搅拌机电机因过载而堵转，造成电机烧毁。


内容简介：
1英文原文：Designing and Modeling a Torque and Speed Control Transmission (TSCT)1 BackgroundThe Partnership for a New Generation of Vehicles (PNGV) was formed between the Federal Government, Ford Motor Company, General Motors Corporation, and Chrysler Corporation. The goal of this partnership was to allow the major U.S. automotive manufactures to collaborate with each other and produce high fuelefficiency, low emissions vehicles for sale to the general public. The performance objective for these manufacturers was to create mid-sized passenger cars capable of attaining an 80 mpg (gasoline) composite fuel economy rating on the Environmental Protection Agency (EPA) city and highway cycles. Hybrid vehicle technology has shown great promise in attaining the goals set forth by the PNGV. Hybrid electric vehicles (HEVs) employ technology that helps bridge the gap between the future hope of an electric vehicle (EV) and todays current vehicles.Within the past year hybrid electric vehicles have gained an important place in the vehicle market. American Honda Motor Company, Inc. is currently releasing their first generation HEV, the Insight. The Insight is a compact, two passenger, parallel HEV which achieves more than 65 mpg (composite) on the EPA test cycles: the highest of any production vehicle ever tested. Toyota Motor Corporation has also released a hybrid vehicle for sale to the general public. The Toyota Prius is currently for sale in Japan and will come the United States in the beginning of the year 2000. The Prius is a four passenger combination hybrid employing an a gasoline engine, high power electric motor, and an electromechanical continuously variable transmission (CVT) comprised of a planetary geartrain and a high power alternator/motor. It is through technology incorporated in vehicles such as the Prius that automotive transmission design and operation will make significant new advances.1.1 Current Automotive Transmission TechnologiesWith the advent of the automobile also came the creation of the automotive transmission. Early vehicles were simple with manual controls for all functions including the transmission. As advances have been made in vehicles over the past several decades, transmission technology has also advanced. The automatic transmission has nearly replaced the manual transmission in all but economy and performance cars. This trend can be attributed to ease of use, higher power engines becoming available, and congestion in urban areas. Another new transmission technology beginning to see application particularly in foreign markets is the continuously variable transmission that offers continuous operation without shifting between a high and low gear ratio.These three types of transmissions are all similar in function though their objectives are accomplished in different ways. The capabilities of these transmissions are limited to decoupling the engine speed from the speed of wheels and thereby providing one of several forward or reverse gear ratios. Each transmission is also a single input (engine) and single output (drive device). There are typically no provisions for attaching multiple power sources or for extracting power from more than one point.The exception to this is heavy-duty transmissions equipped with provisions for a power take off for driving auxiliary mechanical equipment. Single input, single output operation limits drivetrain flexibility for newer systems employing multiple power sources 2such as those used in the next generation of hybrid vehicles.1.1.1 Manual Transmission OperationManual transmissions are the least complex and oldest design of power transmission available. In simplest form, a manual transmission is a linear combination of a clutch and a directly geared connection. More sophisticated examples rely on this design but add the ability to select other gear ratios to allow different output speeds for the same input speed. Of these types of transmissions, there are two variations: synchronized and unsynchronized. Synchronized manual transmissions are typically used for light duty applications. Coupled to each gear is a synchronizer that allows the operator to disengage the clutch and select whatever gear necessary. The selection of a different gear engages the synchronizer, which then matches engine input speed and transmission output speed before the gears are engaged.Unsynchronized manual transmissions are more robust by nature. The operator must double-clutch between shifts to match engine and transmission speed manually. However, this allows a transmission of a given size to handle greater load as space previously occupied by the synchronizers can now be dedicated to the use of wider gears. Applications of these types of manual transmissions are for over-the-road trucks and up to larger equipment with total vehicle weights over 100 tons. 11.1.2 Automatic Transmission OperationAutomatic transmissions are a complex assembly of many components that allow for seamless power transmission. Those currently available in production vehicles use torque converters, clutches, and planetary gear sets for the selection of different output ratios. The engine is connected to the torque converter that acts very much like a clutch under some conditions while more like a direct connection in others. The torque converter is a hydraulic coupling that will slip under light load (idle), but engage progressively under higher load. While the torque converter transmits power to the transmission there is a speed reduction across the unit during low speed operation. This reduction is typically between 2.5:1 to 3.5:1. Once higher vehicle speeds are attained, the torque converter input and output may be locked together to achieve a direct drive though the unit. The output of the torque converter is typically connected to a hydraulic pump that provides the necessary pressure to engage different clutches within the transmission and the planetary drive. Different gear ratios are created through the use of two or more planetary gearsets. These gearsets are combined with clutches on different elements. By clutching and declutching different elements, multiple gear ratios are possible.Basic automatic transmissions are equipped with a single control input that is throttle position. The combination of this with the hydraulic pressure created within the transmission allows for mechanical open loop control of all gear selections. Newer variations of the automatic transmission are equipped with electronic feedback controls.Shift logic is dependent on many more variables such as engine speed, temperature, current driving trend, throttle position, vehicle accelerations, etc. This allows the transmission controller to monitor vehicle operation and using a rule-based control strategy decide which gear is best suited to the current driving conditions. Newer systems are also integrated with the engine controller such that a vehicle control computer has authority over engine and transmission operation simultaneously. This allows for such features as increasing engine speed during high-speed downshifts to match engine 3and transmission speed for smoother shifting and retarding fueling and ignition timing during high power upshifts to reduce jerk. Previously, transmissioncontrol was much simpler because overrunning clutches were employed in higher gears that only allowed for coasting to conserve fuel. 11.1.3 Continuously Variable Transmission OperationContinuously variable transmissions are one of the emerging transmission technologies of the last twenty years. This type of transmission allows power transmission over a given range of operation with infinitely variable gear ratios between a high and low extreme. These transmissions are constructed using two variable diameter pulleys with a belt connecting the two. As one pulley increases in size, the other decreases. This is accomplished by locating on one shaft a stationary sheave and a movable sheave. For automotive applications, a hydraulic actuator controls movement of the sheave. However, centrifugal systems along with high power electronic solenoids may be used. A second shaft in the CVT contains the other stationary sheave and movable sheave also controlled hydraulically. A flexible metal belt is fitted around these two pulleys and the movable sheaves are located on opposite sides of the belt.There are two variations of this type of transmission: push belt and pull belt. Pull belt CVTs were the first type to be manufactured due to simplicity. A clutch is attached between the first pulley and the engine while the output of the second pulley was connected to a differential and thus the wheels. A hydraulic pump is used to control the diameter of the two different pulleys. As power is applied the first pulley creates a torque that is transmitted through the belt (under tension) to the second pulley. Control of the transmission ratio is usually a direct relationship dependent upon throttle position.Push belt CVTs, similar in design to the Van Doorne, are much the same as pull belt CVTs, except that power is transmitted through the belt while under compression. This provides a higher overall efficiency due to the belt being pushed out of the second pulley and lowering frictional losses. Current work with these transmissions is being focused on creating larger units capable of handling more torque. Efficiency of the CVT is directly related to how much tension is in the belt between the two pulleys. CVT torque handling capacity increases as tension in the belt increases. However, this increased tension lowers power transmission efficiency. The belt must slide across the faces of each pulley as it enters and exits upon each half rotation. This sliding of the belt creates frictional losses within the system. In addition, there may be significant parasitic losses associated with raising the hydraulic pressure required to move or maintain the position of the sheaves in each pulley. 21.1.4 Automatically Shifted Manual Transmission OperationAutomatically shifted manual transmissions are a fairly recent innovation. The benefit of the manual transmission is that (due to the direct mechanical connection through fixed gears) efficiency is very high. The drawback is that there must be some interaction with the user in the selection and changing of gears. Automatically shifted manuals were created to address this issue. These types of transmissions are traditionally synchronized manual transmissions with the addition of automation of the gear selection and control of the clutch. A logic controller is also employed to decide when and how to shift. Automatic shifting is usually accomplished through the use of electro-hydraulics. A 4high-pressure electric pump supplies pressure to hydraulic solenoids that are used to shift the transmission. A hydraulic ram is also used to engage and disengage the clutch. Current versions of these transmissions also employ unsynchronized gears. This allows for overall smaller packaging to accomplish the same task. Input speed of the engine is monitored along with layshaft speed. When a gear change is initiated, the controller opens the clutch, shifts to the desired gear while matching engine and lay shaft speed, and then closes the clutch again. This shifting operation can all be achieved in less than one third of a second. Automatically shifted manual transmissions shift gears faster than humanly possible. 31.1.5 Manually Shifted Automatic Transmission OperationManually shifted automatic transmissions are a variation on control of the transmission. The user is allowed to select either automatic or manual shifting modes. During automatic mode, the transmission functions identically to an automatic transmission. While in manual shift mode however, the transmission controller allows the user full authority over gear changes as long as the gear change will not overspeed the engine. This mode of operation traditionally offers the user tighter, more positive shift feel. The only requirement of an automatic transmission for manual shifting is that shifts must be accomplished rapidly enough to allow the user a feeling of fluidity. The act of shifting must provide the immediate desired response. 31.1.6 Planetary Gear Drive Transmission OperationPlanetary gear sets are unique in that the combination of gears creates a twodegree-of-freedom system. The gear sets are comprised of a ring gear, a sun gear in the center, and planetary gears that contact both the ring and the sun gears. Motion of the planetary gears is controlled by the carrier on which each of the planetary gears rotate.The carrier maintains the position of the planets in relation to each other but allows rotation of all planets freely. Inputs (or outputs) to the gear train are the ring gear, sun gear, and planetary carrier. By prescribing the motion of any two of these parameters, the third is fixed in relation to the other two. By employing one planetary geartrain, a fixed ratio between input and output is created. Increasing or decreasing the number of teeth on the sun and ring gears can change this ratio. This in turn changes the number of teeth on the planetary gears, which has no other effect as these gears act as idlers.When combining more than one planetary gear train at one time, braking or allowing the movement of different elements can create a wide range of effective operation in terms of relative speeds, torque transfer, and direction of rotation. This is the type of system that is used in automatic transmissions described above. These systems are also employed in large stationary power transmission applications. 11.2 Current Hybrid Electric Vehicle Transmission DesignHybrid vehicles are vehicles that utilize more than one power source. Current propulsion technologies being favored are compression ignition (CI) engines, spark ignition(SI) engines, hydrogen-fueled engines, fuel cells, gas turbines, and high power electric drives. Energy storage devices include batteries, ultra-capacitors, and flywheels.Hybrid powertrains can be any combinations of these technologies. The aim of these vehicles is to use cutting edge technology combined with current mass-produced components to achieve much higher fuel economy combined with lower emissions without 5raising consumer costs appreciably. These vehicles are targeted to bridge the gap between current technology and the future hope of a Zero Emission Vehicle (ZEV), presumably a hydrogen-fueled fuel cell vehicle. The operation of these systems must also be transparent to the user to enhance consumer acceptability and the vehicle must still maintain all required safety features with comparable dynamic performance all at an acceptable cost.By combining multiple power sources, overall vehicle efficiency can be improved by the ability to choose the most efficient power source during the given operating conditions. This is key in improving vehicle efficiency because current battery technology dictates that nearly all total energy used by the vehicle across a reasonable range of driving comes from the on-board fuel. Highly adaptive control strategies that may be employed in the next generation of HEVs may monitor vehicle speed, desired torque, energy available, and recent operating history to choose which mode of operation is most beneficial. These advanced control schemes will maximize the usage of the fuel energy available by choosing the most efficient means of power delivery at any instant. The reduced usage of energy for a given amount of work may also result in lower exhaust emissions due to a reduction in fuel energy used.1.2.1 The Advantages and Disadvantages of Series Hybrid VehiclesSeries hybrid vehicles typically have an internal combustion engine (ICE) that iscoupled directly to an electric alternator. The vehicle final drive is supplied entirely by an electric traction motor that is supplied energy by the battery pack or combination of engine and alternator. The benefit of this type of operation is the engine speed and torque are decoupled from the instantaneous vehicle load and the engine needs only to run when battery state of charge (SoC) has dropped below some lower level. This allows engine operation to be optimized for both fueling and ignition timing in the case of a spark ignited engine, or fueling and injection timing for a compression ignition engine. The engine is also operated in the most efficient speed and torque without encountering transient operation regardless of load. The result is excellent fuel economy and low emissions. Series HEV operation is exceptionally well suited to highly transient vehicle operation which is prevalent in highly urban areas and city driving. The disadvantage to series hybrid operation is the efficiency losses associated with converting mechanical to electrical and then electrical to mechanical energy. Further losses in system efficiency are realized when the energy is stored in the battery pack for later use. Only a fraction of the energy put into the batteries can be returned due to the internal resistance of the batteries. The mechanical energy of the engine is directly converted to electricity by an alternator that has losses both in internal resistance and eddy currents present. Further losses are incurred when this electrical energy is converted back to mechanical energy by the traction motor and controller. Dynamic performance is also limited, as the engine cannot supplement the traction motor in powering the vehicle.1.2.2 The Advantages and Disadvantages of Parallel Hybrid VehiclesParallel systems also employ two power sources, typically an engine and a traction motor with both directly coupled to the wheels typically through a multi-speed transmission. This requires that the engine see substantial transient operation. However, the motor can act as a load-leveling device allowing
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