自行走轮椅(全套含cad图)
自行走轮椅(全套含cad图),行走,轮椅,全套,cad
自动走轮椅 学生姓名:梁 超 班级:0681053指导老师:袁 坤 摘要:为实现高性能和低成本的自行走轮椅, 开发了全数字自行走轮椅控制器; 采用先进的无速度传感器测速技术, 设计了带电流补偿的电压负反馈加负载不平衡补偿的双电机协调控制方案。驱动部分采用有刷幅条电机的后轮驱动。幅条电机传动具有转矩大、噪音低、效率高、耗电少、寿命长、绿色环保等优点,克服了链传动噪声大、冲击大、传动不平稳等缺点,且外观新颖,控制部分采用采用平等四边形连杆机构,结构简单,并实现了大角度的转向控制和两轮同步运动,同时增加轮椅在行进中的稳定性,而且起到防倒的功能,遇上下坡也能自主掌控,安全性高;制动部分采用特制的涨刹机构,达到前后手柄都可以制动,安全性高。 给出了软硬件结构和单元电路的设计及参数选择方法; 分析了操纵杆工作原理; 给出了轮椅速度和运动方向信息合成计算公式和提高运行舒适度的S曲线生成策略。关键词: 自行走轮椅; 控制器; 双电机; 协调控制; S曲线; 误差检测;幅条电机;连杆机构;涨刹机构;电动控制;辅助装置 指导老师签名:Automatic walk a wheelchair Student name :Liang Chao Class: 0681053Supervisor: Yuan Kun Abstract: To achieve high performance and low cost to walk the wheelchair, developed by digital controller; walk wheelchairs, Using advanced speed sensorless speed technology, design with the current compensation voltage feedback and compensation of unbalanced load motor coordination control scheme. Driving part adopts a brush painting of the rear wheel drive motor. The picture has great torque motor drive, low noise, high efficiency, energy saving.longlife, green environmental protection etc, and overcome the impact noise, large chain drive not smooth, novel appearance and defects, and control part adopts USES equal quadrilateral linkage mechanism, simple structure, and realize the large Angle of steering control and two wheels, adding wheelchairs synchronous movement in the stability and travel, prevent fall function, meets the downhill can independently control, high security, Braking part adopts special rose, and brake to handle all can apply the brake, high safety.The hardware and software structure and given the unit circuit design and parameter selection method, The lever principle analysis, Given the speed and direction of movement wheelchair synthetic formulas and improve information generated the comfort of the S curve operation strategy. Key Words: EPW; Controller; Two2motor; Coordinated control; S curve; Fault detection;electromotive wheelchair;hand control;electric control;auxiliary unitSignature of Supervisor:毕业设计(论文)开题报告题 目 自行走轮椅设计 专 业班 级学 生指导教师 自动走轮椅 摘要:为实现高性能和低成本的自行走轮椅, 开发了全数字自行走轮椅控制器; 采用先进的无速度传感器测速技术, 设计了带电流补偿的电压负反馈加负载不平衡补偿的双电机协调控制方案。驱动部分采用有刷幅条电机的后轮驱动。幅条电机传动具有转矩大、噪音低、效率高、耗电少、寿命长、绿色环保等优点,克服了链传动噪声大、冲击大、传动不平稳等缺点,且外观新颖,控制部分采用采用平等四边形连杆机构,结构简单,并实现了大角度的转向控制和两轮同步运动,同时增加轮椅在行进中的稳定性,而且起到防倒的功能,遇上下坡也能自主掌控,安全性高;制动部分采用特制的涨刹机构,达到前后手柄都可以制动,安全性高。 给出了软硬件结构和单元电路的设计及参数选择方法; 分析了操纵杆工作原理; 给出了轮椅速度和运动方向信息合成计算公式和提高运行舒适度的S曲线生成策略。关键词: 自行走轮椅; 控制器; 双电机; 协调控制; S曲线; 误差检测;幅条电机;连杆机构;涨刹机构;电动控制;辅助装置 指导老师签名:Automatic walk a wheelchair Abstract: To achieve high performance and low cost to walk the wheelchair, developed by digital controller; walk wheelchairs, Using advanced speed sensorless speed technology, design with the current compensation voltage feedback and compensation of unbalanced load motor coordination control scheme. Driving part adopts a brush painting of the rear wheel drive motor. The picture has great torque motor drive, low noise, high efficiency, energy saving.longlife, green environmental protection etc, and overcome the impact noise, large chain drive not smooth, novel appearance and defects, and control part adopts USES equal quadrilateral linkage mechanism, simple structure, and realize the large Angle of steering control and two wheels, adding wheelchairs synchronous movement in the stability and travel, prevent fall function, meets the downhill can independently control, high security, Braking part adopts special rose, and brake to handle all can apply the brake, high safety.The hardware and software structure and given the unit circuit design and parameter selection method, The lever principle analysis, Given the speed and direction of movement wheelchair synthetic formulas and improve information generated the comfort of the S curve operation strategy. Key Words: EPW; Controller; Two2motor; Coordinated control; S curve; Fault detection;electromotive wheelchair;hand control;electric control;auxiliary unitSignature of Supervisor:目 录1 绪论 . 21.1 国内外发展情况 . 41.2 设计内容 .51.3 设计思路 .52 系统方案 .7 2.1 机械系统方案 .72.2 控制方案 .92.3 总体方案 .10 3 机械结构计 .113.1 链条的传动设计 .113.2 电动机的选用 .113.3 驱动电路设计 .124 控制系统设计 .134.1 控制系统软件设计 .145 总结 .145.1 设计总结 . 145.2 展望 . 14参考文献 . 15 附录 .18致谢 . 19 一、绪 论1.1 自行走轮椅国内外发展情况随着社会的发展和人类文明程度的提高,人们特别是残疾人愈来愈需要运用现代高新技术来改善他们的生活质量和生活自由度。因为各种交通事故、天灾人祸和种种疾病,每年均有成千上万的人丧失一种或多种能力(如行走、动手能力等)。随着人口的增长和医疗技术的进步,社会老龄化问题已成为很多国家不得不认真对待的重要问题之一。智能轮椅能够帮助老年人和残障人士独立的生活,节省家庭护理费用,减轻社会负担。许多国家投入较多资金研究智能轮椅,涌现出许多成果,但由于价格和实用性的原因使它们暂时只能作为实验产品。智能轮椅作为移动机器人的一种,主要用来辅助老年人和残疾人的日常生活和工作,是对他们弱化的机体功能的一种补偿.智能轮椅在作为代步工具的同时又可以使用携带的机器手臂完成简单的日常活动.使他们重新获得生活能力,找回自立、自尊的感觉,重新融入社会.因而,智能轮椅的研究得到越来越多的关注 本设计的研究目标:在最经济的条件下,设计出一件最实用、最简易操作的自行走轮椅,功能齐全、结构简单、适用于伤残人士、且能达到消费者需求水准的一件市场普及化产品。 主要特色:功能齐全、结构简便、使用方便、价格适当、安全系数强 电动轮椅技术及其产业化 1产品特点电动轮椅作为一种安装有传感器,具有良好的智能控制功能的电动轮椅,不但具有普通的当前市面上电动轮椅所具有的所有功能,而且可以实现更加友好的人机接口和良好的操作性能。例如,可以实现避碰功能和导航功能,甚至可以实现利用无线方式将使用者的位置和基本状态传送给医护人员和家人实现实时监控。 国内外研究现状及发展趋势(含文献综述): 自动轮椅作为医疗护理领域的服务机器人,其应用大量使用了移动机器人技术在自动轮椅的研究中涉及到的关键技术有导航系统、控制和能源系统、人机接口 但由于整个轮椅系统以人为中心,所以在研究中要解决的核心是轮椅的安全导航问题所谓导航即是指移动机器人按照预先给定的任务命令,根据已知的地图信息作出全局路径规划,并在行进过程中,不断感知周围的局部环境信息,自主地作出各种决策,并随时调整自身位姿,引导自身安全行驶到达目标位置 智能轮椅作为医疗护理领域的服务机器人,其应用大量使用了移动机器人技术。在智能轮椅的研究中涉及到的关键技术有导航系统、控制和能源系统、人机接口,但由于整个轮椅系统以人为中心,所以在研究中要解决的核心是轮椅的安全导航问题。所谓导航即是指移动机器人按照预先给定的任务命令,根据已知的地图信息作出全局路径规划,并在行进过程中,不断感知周围的局部环境信息,自主地作出各种决策,并随时调整自身位姿,引导自身安全行驶到达目标位置。随着社会的发展和人类文明程度的提高,人们特别是残疾人愈来愈需要运用现代高新技术来改善他们的生活质量和生活自由度。因为各种交通事故、天灾人祸和种种疾病,每年均有成千上万的人丧失一种或多种能力(如行走、动手能力等)。因此,对用于帮助残障人行走的机器人轮椅的研究已逐渐成为热点,如西班牙、意大利等国,中国科学院自动化研究所也成功研制了一种具有视觉和口令导航功能并能与人进行语音交互的智能轮椅。近几年来我国轮椅车的生产近几年有了较大的发展,据中商情报网监测数据显示,目前全国规模以上轮椅生产企业约有30多家企业,主要集中在东部及沿海发达地区,外商投资轮椅生产企业在中国轮椅行业占绝对领导地位。近年来随着人口老龄化到来及我国残疾人康复事业的发展,这为轮椅生产企业提供了良好的空间和广阔的市场前景。3同国外产品的综合比较技术水平方面:与国外相比国内已经基本上没有差距,在某些方面甚至还具有一定优势。生产工艺方面:虽然与国外相比还有一定差距,但通过分析解剖国外产品特点,利用自身优势可以在较短时间内缩小这种差距。研发和生产成本方面:与国外相比,国内具有相当大的优势。市场潜力方面:国内电动轮椅市场刚刚启动,尚没有强有力的竞争对手,市场潜力非常大。 4国内现有企业情况介绍首先,国内尚无具备智能轮椅生产的企业,现有的轮椅生产企业还主要定位在电动轮椅的生产上。且由于国内目前上不具备研制开发高性能电动轮椅控制器的能力,国内的生产企业的电动轮椅产品基本上都采用了国外的电动轮椅控制器,甚至部分企业的电动驱动总成也采用了外购方式,因此国内现有企业的产品成本居高不下,影响了市场购买能力的形成。同时由于不得不采用价格昂贵的进口控制器,国内电动轮椅产品的市场售价长期以来居高不下,难以为普通用户接受,也直接影响了电动轮椅市场的启动。 5国家产业支持国家科技发展部门已经看到智能轮椅产业的发展契机,已经从国家的产业发展角度来对其未来的发展进行支持。下图是普通轮椅图 下图为设计的自行走轮椅产品图1.2 设计内容 本设计的是为残疾人士和老年人设计一款自行走轮椅。 自行走轮椅作为老年人和残疾人的代步工具,有着严格的技术要求。轮椅优良的驱动性能和严格的安全性保障是首要的技术要求。技术要求主要如下1. 基本驱动功能 轮椅的模拟给定是由操纵杆发出的, 由速度档位设置按键来设定轮椅最高和最低运行速度。轮椅在起/制动时必须平滑稳定和安全。自行走轮椅对电机的起/制动快速性没有特殊要求, 但对机械特性有相对较高的要求。轮椅必须能够至少爬行5的坡, 能够在草地等比较糟糕的路况下运行, 能够在左/右驱动轮处于不同路面时正常运行。2.故障检测及保护控制器应能自动进行故障诊断、定位和报警,并对一些常见故障进行显示。当轮椅运行时如果检测出故障, 系统能够使轮椅安全停止并锁定;当轮椅静止时出现故障, 系统应能够立即锁定轮椅1.3 设计思路 本品设计的路线是在普通轮椅上增加电路和电动机,用电能来取代手动,从而使伤残人士和老年人更方便使用轮椅。电机选择的是Y160M1,连接电路来带动链条连接机构。用单片机输出、输入信号,连接到轮椅扶手上的控制器,当控制器给出命令的时候,单片机驱动电路,再通过电机带动链条,使整个轮椅能运动起来。 本款自行走轮椅最快速度为10km/h,具备转向、加速、减速、刹车功能。二、系统方案2.1 机械系统方案 图1自行走轮椅运动控制系统示意图 上图1为轮椅运动控制系统组成。可见, 自行走轮椅运动控制系统主要由操纵杆信号处理部分、电机控制部分和轮椅状态检测分组成。操纵杆输出的信号经过操纵杆信号处理部分后被合成为带起/制动S曲线和死区的轮椅的速度和方向给定值。这个给定值就是用户给控制器的控制指令。电机控制部分接收用户的指令和反馈信号来合成电机驱动信号和其他控制信号。这部分是轮椅运动控制系统的核心部分。电机检测部分检测电机和控制器的工作状态。这些检测信号被用作电机的控制信号和其它部分的控制信号。1.1操纵杆输出信号速度给定合成由于操纵杆输出是二维的随着位置变化而成比例变化的电压信号, 故非常适合用来控制自行走轮椅。用户前后推动操纵杆可以控制轮椅的运行速度, 左/右推动可以控制轮椅的转向方向和转向速度的大小。下面介绍怎样把一个二维的操纵杆输出信号转换为速度和转向控制指令。如果把操纵杆的信号看作是二维输出信号,分别在二维坐标系中用X轴和Y轴表示 1 。 图2操纵杆输出信号矢量合成示意图可以将X轴信号看作是轮椅的转向速度给定信号, 而Y轴信号则可以看作是轮椅的前向和后向速度给定信号。因此, 如果用户想要转向和前进,则可将轮椅的运动方向看作是X和Y的矢量合成,如图2中所示F。而左/右电机的速度给定Sl 和Sr可从下式得出 2 : Sl =Cx Fx +Cy FySmax(1) Sr =- Cx Fx +Cy FySmax(2)其中, 设Smax为速度给定最大值, Cx代表轮椅的转向速度特性, 而Cy 则代表轮椅在前向和反向的速度特性。如果以上公式的计算结果大于了轮椅最大转向速度, 则用最大转向速度代替计算结果。 图3表示以不同角度旋转操纵杆时, 轮椅的左/右轮速度给定曲线。如果Sl 和Sr 的值都是正的, 则轮椅向前前进转向, 否则是后退转向。当轮椅向左转时, 右轮正向转动, 左轮反向转动或保持不变; 相反, 当轮椅向右转时, 左轮正向转动, 右轮反向转动或保持不变。当一个轮保持不转动而另外一个轮转动时, 轮椅做原地360转弯。 图3以不同角度旋转操纵杆时轮椅的左/右轮的速度曲线1.2速度给定的S曲线设计(1) 设计思路。S曲线本身是一个非线性函数,其合成和编程都非常复杂。S曲线的形状如图4虚线所示。在轮椅起动时应该是一个抛物线形状, 然后是轮椅的加速过程, 直至轮椅最大速度后, 加速度为零, 轮椅以恒定最大给定速度运行; 制动时,轮椅先以直线的斜率减速, 最后在抛物线段舒缓地停止。本文用图4中的一个折线近似地代替S曲线,用三段折线用来模拟抛物线。这使得编程非常简单,实践证明, 控制效果非常理想。 图4轮椅速度给定的S曲线示意图(2) 实现方法。利用中断时间和人体对加速度变化率的敏感特性来实现。根据人体对加速度和加速度变化率的敏感特性知, 当加速度或减速度最大值不大于1.5 m / s2、平均加减速度不低于0.5 m / s2、加速度变化率小于1.5 m / s3 时, 人体的舒适感比较好。设系统的中断周期为T, 直线的斜率为K, 规定轮椅在t时间内加速到速度给定最大值Smax , 则: K =Smaxt/T=SmaxtT (3)图4中, 三段线段斜率比值为: K1 K2 K3 = 1 1.92 2.6。具体程序实现见第四节。在本系统的设计中, K1、K2、K3 都被设置为可编程调节参数,用户可以根据自己的舒适性要求来进行相应调整。2.2 控制方案设计对调速系统来说, 用转速负反馈可以获得比较满意的静、动态性能。但是, 在本文的自行走轮椅运动控制系统的设计中要实现转速负反馈是非常困难的, 因为无法安装转速检测装置。故在设计中采用电压负反馈和电流补偿的控制方法 3 。如果忽略电枢压降, 则直流电动机的转速近似与电枢两端电压成正比, 所以电压负反馈基本上能够代替转速负反馈的作用。采用电压负反馈和电流补偿控制的调速系统原理图如图5所示 图5电压负反馈和电流补偿控制的调速系统原理图其中, V +、V - 分别为电动机两端的电压。它们同时被送入DSP 的AD采样通道中, 在软件中对V +、V - 进行差分得到电机两端的电压。这样可以消除由于电源电压波动等因素引起的电机端电压的误差。R1、R2 是采样电阻, 之所以有两个采样电阻, 是因为文中所讨论的电动轮椅控制系统采用双极性模式, 可在四象限运行。由如图5所示的H桥可知, R2、R1可分别检测电机的正反向电流。对应的系统控制方框图如图6所示。2.3 总体方案:在多次观察了普通轮椅之后,发现在普通轮椅的座位底部安装双电动机,然后把链条安装在双电动机的连杆上,利用单片机来输出、输入信号,在单片机和双电动机的电路连接下,使整个设计机构有一个完整的回路。从而实现这款自行走轮椅的运行。整个设计思路其实比较是简单的,在安装了设计电路后,通过电动机做功来带动链条传动,来实现自行走轮椅行走、加速、减速、刹车的各项功能。三、机械结构设计3.1 链条传动设计双电机组合带动链条,以电动机产生动力,电带动电动机上的杆和锥齿轮,通过链条的连接机构,而带动车轮连杆上的链轮,这样形成一个整体机构过程。开启电源后,当控制器发出运行命令时,信号通过单片机电路与电动机连接,电动机开始启动,通过链条的传动,带动车轮向前或者向后行驶。3.2 电动机的选用 本设计用的是双电机组合,所以在选择电动机时,依照自行走轮椅运行时最大速度10km/h,来选择电动机。 = =选择的电动机是Y160M1 电动机转速720车轮的转速:则: 实际功率:传动比: 3.3 驱动电路设计 在本设计系统中,选用的是ST公司的L298N电机专用驱动芯片。该芯片的主要特点是:工作电压高,最高工作电压可达46V;输出电流大,瞬间峰值电流可达3A,持续工作电流为2A;内含两个H桥的高电压大电流全桥式驱动器,可以用来驱动直流电动机和步进电动机、继电器、线圈等感性负载;采用标准逻辑电平信号控制;具有两个使能控制端,在不受输入信号影响的情况下允许或禁止器件工作有一个逻辑电源输入端,使内部逻辑电路部分在低电压下工作;可以外接检测电阻,将变化量反馈给控制电路。图中电源和地之间接入了去耦电容,在电机线圈两端分别接入二极管进行过流保护。四、控制系统设计4.1 控制系统软件设计 轮椅运动控制系统总的流程如图7所示。本文设计的轮椅控制系统是纯数字化控制。系统软件采用汇编语言编写, 代码运行效率高; 采用模块化的程序设计方法, 各功能模块之间除接口变量外互相独立。 图7轮椅运动控制系统总程序流程图五、总结5.1 设计总结 本文以自行走轮椅运动控制为背景,依据系统控制方案编制了相应的控制软件, 软件模块化并考虑了参数修改和运行状态显示等功能。经调试和试运行, 技术指标达到了预期要求。从考虑人的舒适性和可靠性出发, 提出了基于电压检测的功率管故障及主电路故障判断、定位的实施方案, 并给出了速度给定S曲线计算公式和软件编程算法。运行效果良好。操纵杆是轮椅运动速度方向和大小的给定装置。 通过分析其原理导出了计算公式, 并通过软件实现取得了良好效果。总之, 本文完成了轮椅运动控制器设计、调试和试运行, 各项指标均达到了预期目标, 验证了硬、软件方案正确性及可行性。 本文的项目设计以国家高技术研究发展计划(863计划)先进制造技术领域“服务机器人”重点项目2006年度课题申请指南中课题l智能轮椅关键技术、单元部件及目标产品的研发的主要考核指标为参考技术标准,目标是构建一个为老年人和残疾人服务的自行走轮椅。 从自行走轮椅功能的角度对轮椅的硬件系统进行模块化设计,将自行走轮椅分为机械结构、驱动、控制三部分。重点介绍了自行走轮椅控制系统,最主要的是设计了DA转换平台,成功接管了智能轮椅核心控制器。利用控制器,成功实现自行走控制系统。在设计电路控制器的工作,让单片机开发板通过程序直接控制轮椅运动。5.2 展望 如前所述,本课题设计自行走轮椅控制系统,基本达到了实用性的要求。但由于多方面的原因,该系统需要进一步的改进与完善,还存在着很多不足。 在采用轮椅控制器控制电机时没有加入测速环节构成闭环反馈控制系统。由于每个用户的体重不同,且轮椅行驶的路面情况不同,根据直流电机负载特性曲线可知,轮椅的实际电机转速将会与设定值不同,这在实际应用中是不应该出现的,虽然在短时间内实现了低成本的控制,仍然无法达到最智能的效果。缺乏机器视觉技术的应用。本项目中图像传感器仅应用于路径跟踪,没有开发复杂的图像处理与识别算法,且此处仅适用于跟踪白色路面上的黑色路标,使用场合有限。应用先进的机器视觉技术能够大大提高轮椅的自主性和智能化。61参考文献1J. 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感谢本组的每一位同学,在毕业设计工作中的真诚协助与交流及生活上给予的诸多帮助。感谢机电分院的众位老师对我的辛勤指导,是你们的悉心教诲让我在大学期间不仅学到很多理论上的知识,也让我懂得了很多的人生哲理。衷心感谢所有关心、支持和帮助过我的老师、同学和朋友们! 最后,谨向百忙之中抽出宝贵时间评审本论文的各位专家致以诚挚的谢意!21毕业设计(论文)题 目 自行走轮椅设计 专 业班 级学 生指导教师 辅助站立轮椅 (文献翻译) 16 辅助轮椅的设计美国专利4519649 摘要:轮椅改良设计使在身体支撑于一个主框架上,可以使坐姿改变而无需使用外部的升降力达到独立的站立姿态。轮椅包括配套驱动轮、辅助轮和机构的支撑,腰部支撑部件和靠背部件彼此形成的主结构。前部的主结构和腰部支撑部件的尖端部分设一个支点,并扩展部件的支撑与支撑腰部支撑的部件,作为支撑点之间的中间点的主要结构和腰部支点支撑部件。依靠推轮椅使用者的力量(身体抬起,使用者通过他或她的上肢的力量)和扩展的力量。1 轮椅的各部件: 1.一个主框架配套驱动轮和辅助轮;身体的支撑框架包括下肢轴互联支撑构件,腰部支撑构件和靠背的构件,该主结构的身体支撑架被作为独立的结构组成,前端部分的腰部支撑构件是身体支撑架轴连接前端部分支点的主体。装有气弹簧的一端,气弹簧的轴连接到主体上,并在其另一端连接轴及其活塞杆腰部支撑部件和架等机构的支撑,扩展和回缩气弹簧的原因,腰部支撑构件旋转支点主体。锁定在可操作的连接,空气为锁定弹簧的气体在任意位置之间的全面伸长和一个完全缩回的位置,以便恢复弹簧在腰部规定的角度范围内任意角度与水平方面的支撑构件其旋转的支点方法,充分伸长,气弹簧相应的座位和站立身体支撑架所述位置,分别表示完全缩回的位置。 2. 其中一个要求1中所示的轮椅,表示锁定方式包括阀门弹簧接收机构,气弹簧的操作杆。安装一个可操作的双节点支撑,操作线进行阀门操作杆表示阀门的连接操作杆,其紧握操作杆,从而允许伸长和收缩的气弹簧,而释放操作杆引起锁定气弹簧,以免伸长或收缩。3.要求1中所示的轮椅,其中腰部支撑构件连接下肢支持构件,通过链接机制。 4.主框架作为3定义轮椅,其中链接机制,腰部支撑的构件,其余构件包括一个平行四边形的4杆的链接。5.作为3定义轮椅,链接机制,腰部支撑的构件,下肢支撑构件包括有一个任意长度的4杆的链接机制。2 说明: 2.1背景 本发明涉及到了轮椅,这使得它可以与一个极其有限的或没有的功能相结合,如截瘫下肢残疾人从坐姿改变他或她的姿势,以独立的姿态,使用其她推力(升残疾人身体由他或她的上肢动作),他或她每天练习,它的动力无需使用任何外部电源。轮椅是一种所需的覆盖范围大幅走相同的议案,并可以作为一种短距离的运输车辆的车辆。因此,轮椅必须有一个全功能作为日常仪器,运动功能。这使得它可以为残疾人开展工作所使用的轮椅。不过,按照的传统轮椅,轮椅的使用者只可以做固定的姿势工作,但能不能做到可以站立的姿势时的工作,因为他或她的手可能不能达到很高的位置。近年来,轮椅使用外接电源(如电机驱动器使用电池作为动力源)为一个独立的机制已经提出了一个轮椅,这使用户可以独立以站姿的姿态下工作。然而,这种轮椅涉及的收费工作和维护复杂的缺点,增加轮椅的重量和轮椅本身有限的多功能性是极其昂贵的。 2.2相关的图纸 FIG. 1是一个侧视图。根据本发明的一个实例中的轮椅; FIG. 2图1的后视图 FIG. 3 是一个透视图显示的状态,其中一个被用来作为一个扩展部件的气弹簧;FIG. 4 是一个图表,显示的座位角度(站立的角度)和应用于座椅和脚踏板的负荷之间的关系3 优选实施的案例:在图1和图2,参考图1代表一个主体,支撑驱动2和第3轮辅助轮。肘支撑4个固定上部的主构件,每边1个。参考5代表身体支撑架肢体较低的支撑部件6,腰部支撑构件7和8靠背构件组成。这些构件是连接相邻部件彼此之间的相对回转的方式。一个脚踏板和着地部件10是固定的低端下肢的支撑构件6。 7腰部支撑构件的尖端是弯曲的并且弓状形式和一个支架11固定弓状部分,其安装前部的主框架由一个支点12 和1。靠背构件8,腰部支撑构件7和下肢支撑构件6连接两个4杆的链接到另一个独立的机构,包括身体支撑架5。在这些链接,靠背8部件和腰部支撑部件7环节是连接A和B的支点12 1 4杆的平行四边形链接,并链接腰部支撑构件7和下肢的支撑构件6是一个4杆的链路连接的部件,6,7和链接C至支点12之间的联合,并可能有一个任意的或可选的长度。这两个链接机制是安装在主体1。一个气弹簧作为一个升缩的部件13中间之间的主体1和腰部支撑构件7收缩的弹簧13支撑,可以提高和支持点作为支点12腰部支撑构件7 。这气弹簧是一种利用高压气体密封在缸14如图压力的一个弹簧。 部件3启动,并在任意位置停止,活塞和气缸内的活塞连接到一杆15。一个气弹簧接收机构16安装到主体1,而15杆装有腰部支撑构件7。操作一个阀门的操作按钮17(以下简称为“锁定按钮”),可以通过远程控制操作杆18安装到手肘支撑成员4。在图纸上,参考数字19代表的操作线20是一个阀门操作杆。当操作杆18启动,阀门操作杆20和17阀门的操作按钮被启动箭头指示的方向和释放锁气弹簧13。握操作杆18时被释放,另一方面,阀操作杆20和17阀门的操作按钮启动以相反的方向锁定,即气弹簧13。在轮椅上,动力依靠推轮椅的用户(推高了用户的上肢身体力量)和反应气弹簧的力量。用户可以通过使用这两种力的独立姿态。的使用方式如下。轮椅上站起来,需要先刹车,膝盖和腰部使用者的身体会被牢牢地固定皮带轮椅。准备完成后,安装操作杆18肘支撑构件4可启动,气弹簧17锁定按钮被压下,以便打开气弹簧锁。在气弹簧的锁被释放的阶段,开始动作。在这种情况下,用户把他或她的手的手肘支撑件4,然后推动机构,以减少他或她的体重经座位15杆气弹簧,这样延伸,使气体反应的座位轮椅开始提升。用户在待机期间,18杆处在一个理想的高度,以消除锁定按钮17的推力和锁定气弹簧。因此,可以固定在那个位置的座位。要返回从站立的姿势到坐姿,首先锁定气弹簧被释放的18杆,并同时抓住肘部支撑件4用户会降低他或她的身体,以能够使引导他她的体重的座位上。在这种情况下,用户的重量,克服了气体反应和杆气弹簧的合力,这样的座位开始缓慢降低。在这种情况下,用户可以固定在所需的位置锁定气弹簧座椅。以上所述,站立时腰部支撑构件的最大角度相对水平面为75度,其角度可以很容易地设置用户所需的任何值。在站立的的靠背部件8角度可始终保持不变,使链接8构件和腰部支撑成员7的平行四边形的4杆的水平。下肢支持成员6部分可以逐步扩展方面的腰部支撑构件按7,以便它可以对应的伸长与他或她的膝关节他或她的膝盖以下的部分用户在伸长的位置行动。这个伸长的实现,因为有一个任意长度的4杆链接腰部支撑部件7和下肢的支撑构件6的链接。在以上所述的阐述中,延伸的数量是50毫米,最大的站立,但值可以适当调整,根据用户的愿望。俯卧的支撑是站立时必要,直到腰部支撑部件7变为相对水平面的30,但超过30时,站立只能由气弹簧的力量来完成。其他各种调整,可根据用户的重量,通过适当调整气弹簧的反应,此外,气弹簧,可轻松更换。图4底角(独立角度的腰部支撑构件7)和负载之间的关系是一个图表,显示一个座位和座位之间的角度和负载B脚踏板9。横坐标代表的座位角(度),纵负荷(kgf)。从图中可以明显的看出,主要承担用户的重量座位时的角度小,是由脚踏板和座椅时的角度是较大的承载。因此,用户可以不施加过多的力量需要保持坐姿或站立的姿势。此外,部分是因为体重的载荷,甚至在座位的最高站立时,用户可以放心对背部,并顺利的工作在站立姿势。虽然是固定的脚踏板和着地部件10下肢支撑构件在上述体现6中,用户可以移动,同时保持独立的姿态,如果还装有小轮子的轮椅。驱动轮也可能是其操作开关的电动型,安装操作方便轮椅手肘支撑。虽然是不可折叠的轮椅但它可以改变一个可折叠的类型纳入一个折叠的机制。按照本发明,身体支撑架由下肢支撑构件,腰部支撑构件和靠背机构8驱动伸长部件的链接机制的巧妙结合。因此,轮椅使用者可以很容易地从坐姿改变到一个独立站立的位置,反之亦然。即使当用户承担独立的姿态,他或她可以支持身体的支撑框架,使他或她能够顺利地开展工作在独立的站姿姿态。由于用户可以利用和保持独立的姿态,褥疮和残疾人关节挛缩与很少或没有下肢的功能是可以预防的。伸缩机构的气弹簧的使用,使得其持续并顺利地从坐姿改变身体的位置姿态,反之亦然。可以设置其位置,并固定在所需的姿态,更可以使用户在没有任何帮助的情况下的姿势转变。此外,从坐姿转移到独立的姿态,反之亦然,因为手动都可以生效,本发明的轮椅操作简便,并能消除用户反复使用和保养所造成可能的危险。 .WheelchairUnited States Patent 4519649 Abstract:A wheelchair is disclosed in which a body support frame pivoted to a main frame can move from a seated posture to a stand-up posture and vice versa without using an external elevating force. The wheelchair includes the main frame for supporting driving wheels and auxiliary wheels and a body support frame formed by interconnecting a lower limb support member, a waist support member and a back rest member to one another. The forward portion of the main frame and the tip portion of the waist support member are turnably supported by a pivot, and an extension member for turnably supporting the waist support member with the pivot as the support point is interposed between the main frame and the waist support member. The motive force for the stand-up operation of the body support frame relies upon the push-up force of the user of the wheelchair (the body lift-up force of the user by his or her upper limbs) and the force of the extension member.1. A wheelchair comprising: a main frame supporting driving wheels and auxiliary wheels;a body support frame including pivotally interconnected lower limb support member, waist support member and backrest member, said main frame and said body support frame being formed as independent structures, a front end portion of said waist support member of said body support frame being pivotally connected to a front end portion of said main frame by pivot means;a pair of elbow supports each fixed to an upper portion of said main frame at respective sides thereof, said waist support member of said body support frame being disposed between said pair of elbow supports in a seating position of said body support frame;a gas spring fitted, at one end thereof, to a gas spring receiver pivotally connected to said main frame, and pivotally connected at its other end by a piston rod thereof to said waist support member of said body support frame such that extension and retraction of said gas spring causes said waist support member to rotate about said pivot means with respect to said main frame; andlocking means in operable connection with said gas spring for locking said gas spring in an arbitrary position between a fully extended and a fully retracted position so as to fix said waist support member at an arbitrary angle with respect to the horizontal within a prescribed angular range of its rotation about said pivot means, said fully extending and fully retracted positions of said gas spring corresponding to seating and standing positions of said body support frame, respectively.2. A wheelchair as defined in claim 1, wherein said locking means comprises a valve operation lever carried by said gas spring receiver for operating a valve of said gas spring, an operation lever mounted on one of said pair of elbow supports, and an operation wire operably connecting said valve operation lever and said operation lever, whereby gripping of said operation lever operates said valve thereby permitting extension and retraction of said gas spring whereas releasing said operation lever causes locking of said gas spring so as to prevent the extension or retraction thereof.3. The wheelchair as defined in claim 1, wherein said waist support member and said back rest member, and said waist support member and said lower limb support member are connected to said main frame by link mechanisms, respectively.4. The wheelchair as defined in claim 3, wherein said link mechanism for said waist support member and said back rest member consists of a parallelogrammic 4-rod link mechanism.5. The wheelchair as defined in claim 3, wherein said link mechanism for said waist support member and said lower limb support member consists of a 4-rod link mechanism having an arbitrary length.Description:BACKGROUNDThis invention relates to a wheelchair which makes it possible for the handicapped with an extremely limited or no lower-limb function such as a paraplegic to change his or her posture from a seated posture to a stand-up posture and vice versa, using his or her push-up force (the body lift-up action of the handicapped by his or her upper limb) which he or she daily exercises, as the motive force, without using any external power.The wheelchair is a kind of vehicle which is required to cover a range of motion substantially the same as walking and can be regarded as a short-distance transportation vehicle. Accordingly, the wheelchair must have a full function as a daily instrument, a moving function and a function which makes it possible for the handicapped to carry out work by use of the wheelchair. However, in accordance with the conventional wheelchair, the user of the wheelchair can do the work only in the seated posture but cannot do work which can be done only in a stand-up posture because his or her hands cannot reach a high position.Wheelchairs using an external power source (such as motor drive using a battery as the power source) for a stand-up mechanism have been proposed in recent years for a wheelchair which enables the user to do a work in a stand-up posture. However, the wheelchairs of this kind involve the drawbacks that the charging work and maintenance are complicated, that the weight of the wheelchair increases and that the wheelchair itself is extremely expensive with limited versatility.DRAWINGSFIG. 1 is a side view showing the wheelchair in accordance with one embodiment of the present invention;FIG. 2 is a rear view of FIG. 1;FIG. 3 is a perspective view showing the state in which a gas spring as an extension member is used; FIG. 4 is a diagram showing the relation between the seat angle (stand-up angle) and the load applied to the seat and to the foot plate.PREFERRED EMBODIMENTIn FIGS. 1 and 2, the reference numeral 1 represents a main frame which supports driving wheels 2 and auxiliary wheels 3. An elbow support 4 is fixed to the upper part of the main frame 1 on each side. Reference numeral 5 represents a body support frame which consists of a lower limb support member 6, a waist support member 7 and a back rest member 8. These members are connected in such a manner that the adjacent members are turnable relative to each other. A foot plate 9 and a landing member 10 are fixed to the lower end of the lower limb support member 6. The tip of the waist support member 7 is bent in an arcuate form and a bracket 11 is fixed to the arcuate portion and is turnably fitted to the forward portion of the main frame 1 by a pivot 12. The stand-up mechanism of the body support frame 5 consists of the back rest member 8, the waist support member 7 and the lower limb support member 6 which are connected to one another by two 4-rod links. Among these links, the link for the back rest member 8 and the waist support member 7 is a parallelogrammic 4-rod link connecting the links a and b to the pivot 12, and the link for the waist support member 7 and the lower limb support member 6 is a 4-rod link which connects the joint between the both members 6, 7 and the link c to the pivot 12 and may have an arbitrary or optional length. These two link mechanisms are fitted to the main frame 1.A gas spring 13 as an extension member is interposed between the main frame 1 and the waist support member 7 so that the retracting motion of the spring 13 supports and can raise up and down the waist support member 7 with the pivot 12 as the support point. This gas spring is a kind of spring which utilizes the pressure of a high pressure gas sealed in a cylinder 14 as shown in FIG. 3 so that a piston and a rod 15 connected to the piston inside the cylinder are actuated and are stopped at an arbitrary position. A gas spring receiver 16 is fitted to the main frame 1 while the rod 15 is fitted to the waist support member 7. A valve operation button 17 (hereinafter referred to as a lock button) can be operated by remote-controlling an operation lever 18 which is fitted to the elbow support member 4. In the drawings, the reference numeral 19 represents an operation wire, and 20, a valve operation lever.When the operation lever 18 is gripped, the valve operation lever 20 and the valve operation button 17 are actuated in the direction indicated by an arrow and release the lock of the gas spring 13. When the grip of the operation lever 18 is released, on the other hand, the valve operation lever 20 and the valve operation button 17 are actuated in the reverse direction whereby the gas spring 13 is locked.The motive force of the stand-up of the wheelchair in this embodiment relies upon the push-up force of the user of the wheelchair (the force of pushing up the body by the users upper limbs) and the reaction of the gas spring. The user can take the stand-up posture by use of these two kinds of force. The mode of use is as follows.To stand up, the wheelchair may first be braked, and the knees and waist of users body may then be fixed firmly to the wheelchair by a belt. After this preparation is completed, the operation lever 18 fitted to the elbow support 4 may be gripped and the lock button 17 of the gas spring is depressed so as to release the lock of the gas spring. In the stage where the lock is released, the gas spring starts operating. In this instance, the user puts his or her hand upon the elbow support 4 and then pushes up to reduce his or her weight acting upon the seat so that the rod 15 of the gas spring extends due to the gas reaction and the seat of the wheelchair starts elevating. During stand-up, the user releases the grip of the operation lever 18 at a desired height so as to eliminate the push force of the lock button 17 and to lock the gas spring. The seat can thus be fixed at that position.To return to the seated posture from the stand-up posture, first the lock of the gas spring may be released by the operation lever 18 and the user may then lower his or her body while gripping the elbow support 4 so as to apply his or her weight to the seat. In this instance, the weight of the user overcomes the gas reaction and the rod of the gas spring contracts so that the seat starts lowering slowly. In this case, too, the user can fix the seat at a desired position by locking the gas spring.In the embodiment described above, the maximum angle of stand-up of the waist support member is 75 degrees relative to the horizontal but the angle can be easily set to any value desired by the user. The angle of the back rest member 8 during stand-up can be always kept constant with respect to the horizontal by the parallelogrammic 4-rod link for the back rest member 8 and waist support member 7. The portion of the lower limb support member 6 can extend gradually with respect to the waist support member 7 so that it can correspond to the extension of the portion of the user below his or her knees with the extension of his or her knee joint during stand-up. This extension is attained because the link for the waist support member 7 and the lower limb support member 6 is constructed by the 4-rod link having an arbitrary length. In the embodiment described above, the quantity of extension is 50 mm with respect to the maximum stand-up but the value can be properly adjusted in accordance with the users desire. Push-up during stand-up is necessary until the waist support member 7 becomes 30 relative to the horizontal but when it exceeds 30, stand-up can be accomplished only by the force of the gas spring. Various other adjustments can be made in accordance with the weight of the user by appropriately adjusting the reaction of the gas spring and moreover, the gas spring can be replaced easily.FIG. 4 is a diagram showing the relation between the seat angle (the stand-up angle of the waist support member 7) and the load A applied to the seat and between the seat angle and the load B applied to the foot plate 9. The abscissa represents the seat angle (degrees) and the ordinate the load (kgf). As is obvious from the diagram, the weight of the user is primarily borne by the seat when the angle is small and is borne by the foot plate and the seat when the angle is great. Accordingly, the user can keep the seated posture or the stand-up posture without the need of exerting an excessive force. Moreover, since a part of the weight is borne by the seat even at the time of the maximum stand-up, the user can rest against the back and smoothly carry out work in the stand-up posture.Although the foot plate 9 and the landing member 10 are fixed to the lower end of the lower limb support member 6 in the foregoing embodiment, the user can move the wheelchair while keeping the stand-up posture if small wheels are further fitted. The driving wheel may also be of an electric type with its operation switch being fitted to the elbow support member for easy operation of the wheelchair. Although the wheelchair of the foregoing embodiment is not foldable, it can be changed to a foldable type by incorporating a folding mechanism.In accordance with the present invention, the body support frame consists of the lower limb support member, the waist support member and the back rest member 8 and is actuated by the ingenious combination of the extension member with the link mechanisms. Accordingly, the user of the wheelchair can easily change from a seated position to a stand-up position and vice versa. Even when the user assumes a stand-up posture, he or she can support his or her body by the body support frame so that he or she can smoothly carry out a work in the stand-up posture. Since the user can take and keep the stand-up posture, decubitus and contracture of the joints of the handicapped with a minimal or no lower-limb function can be prevented. The use of the gas spring as the extension member makes it possible to continuously and smoothly change the body support frame from the seated posture to the stand-up posture and vice versa. The seat can be set and fixed at a desired position even during the shift of the posture without any difficulty to the user. Moreover, since the shift from the seated posture to the stand-up posture and vice versa can all be effected manually, the wheelchair of the present invention is easy to operate and can eliminate otherwise likely dangers to the user and complicated maintenance procedures.16
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