【作者】 郭毅军；

【导师】 蔡绍皙；

【作者基本信息】 重庆大学 ， 生物医学工程， 2008， 博士

【摘要】 手术动力装置是开展神经外科手术的必备医疗器械之一,其功能主要是用于开颅、颅底及脊柱手术中对骨组织的处理如钻、铣、磨、锯。近年来,我国临床医学发展迅速,作为医学前沿领域的神经外科发展尤为突出,一是神经外科手术开展的普及程度提高(目前大部分县级医院都已能开展神经外科手术),二是神经外科手术的精细复杂程度大大提高,充分的安全性是应该考虑的首要问题之一。这样一方面形成了手术动力装置的更大市场需求,另一方面对手术动力装置的技术及质量提出了更多更高要求。手术动力装置在神经外科中的应用一般有两种情况,开颅及颅底打磨,这两类手术实施过程中都有极大的风险性,如颅骨钻钻穿颅骨板后必须及时停止,否则会钻入脑组织造成伤害,而颅底或脊柱手术中磨钻摆动过大或操作不当,会伤及神经及血管,易致残致瘫,甚至导致死亡。手术对产品的安全要求极高,所以产品关键技术需认真加以研究。从市场实际情况来看,国内市场高端手术动力装置主要依赖进口,绝大部分用户还在使用木工钻、手摇钻等原始工具进行手术,手术效率很低,医生劳动强度很大,并且手术风险较高,同时每年还要消耗大量外汇,因此这一状态急需改变。在此背景下,作者提出了DK手术动力装置的研究开发,并将其中部分关键技术研究作为本人博士论文课题。手术动力装置是一个较为复杂的系统,广泛涉及精密机械传动、材料、计算机软硬件、电气控制、生物医学等学科技术,但由于篇幅限制,本人重点选择了对产品功能实现及手术安全影响度较大的软轴、钻手机以及主机热可靠性作为主要研究内容。手术动力装置在神经外科中的应用之一开颅(颅骨钻孔及切割),对动力要求大,而对速度要求不高;之二颅底骨组织或脊柱打磨,对动力要求不高,但对速度要求很高,并要求操作手机小尺寸,径向跳动量极小。手术动力装置分为软轴驱动和微电机驱动两类,两类工作方式各有其优缺点,软轴驱动采用大功率交流电机,动力较大,可很好满足开颅手术,其不足是系统可达到的终端输出速度较低(一般小于2万r/min),并且手机部件等尺寸较大,无法满足有高速(如4～8万r/min)、小尺寸要求的颅底与脊柱手术;而微电机方式正好相反,具备高速、小尺寸的技术特点,满足颅底与脊柱手术高速、小尺寸要求,但其功率小(一般只有几十瓦),进行开颅手术就较难。传统手术动力装置产品都仅有一种工作模式,这样临床应用很难同时满足开颅、颅底及脊柱打磨的需要。开发一种同时可满足开颅、颅底及脊柱打磨需要的手术动力装置的需求就这样形成了。本人创新性地将软轴及微电机方式融合于一台设备,很好地解决了这一问题,二种方式的融合使主机控制更加复杂,形成了一个新主机热可靠性问题,通过研究,这一问题得到了很好的解决。而软轴、钻手机及钻头作为手术动力装置非常关键的部件,其性能如振动、发热、柔软性、噪声、重量与尺寸等因素直接影响着手术动力装置功能的效用及安全性。本论文在深入研究神经外科手术动力装置的相关技术和产品现状的基础上,综合生物医学工程、机械学、材料学、力学、现代控制理论和计算机科学,提出了基于大功率电机驱动、大扭矩传递的软轴,并结合高速微电机驱动。采用软轴驱动与微电机驱动两种动力传输方式,使其功能与功能实现的途径达到了最佳的匹配。在这种设计方案中有关软轴的驱动设计是重点也是难点,有关软轴及其相关部件的设计涉及以下四个方面的内容:(1)据装置中软轴传动的性能要求,对其组件进行了详细的力学和性能分析,建立了力学模,提出了软轴的抗弯、抗扭强度和刚度,提出了软轴的抗弯、抗扭强度和刚度计算理论,并最终试制出了合乎要求的软轴。(2)采用有限元分析方法,分析了软轴连接结构件(如连接轴)部的动力学和静力学指标,实现了传动连接件的优化设计。(3)为实现颅骨钻手术中大动力输出的要求,本论文设计和优化了行星齿轮传动系统的技术方案。采用非均匀有理B样条曲线逼近技术对齿形轮廓进行构造,利用构造实体几何方法构造了行星齿轮系统及部件的参数化特征模,应用有限元技术对这些重要动力传输构件的受力和运动进行仿真分析优化,设计和开发了具有足够的强度和动力学传递性能,实现噪音小、平稳、1:6减速比的增力机构。(4)主机内部电气元器件的功率和热耗散功率较大,论论文采用有限差分法,研究了基于有限差分控制体积计算,对主机箱三维结构导热和流体流动进行数值模拟分析,获得了主机的结构布局设计对温度分布和三维冷却流体流动的影响,优化了部件布局和风扇通风窗的参数。本论文研究的技术创新点和主要研究成果:(1)创新点1:微动力与大动力结合。DK-2000A手术动力系统同时采用软轴驱动与微电机驱动两种动力传输方式,使其功能与功能实现的途径达到了最佳的匹配,可应用于神经外科手术中常用的钻、铣等功率要求较大的功能和高速打磨及钻微孔功能。(2)创新点2:研制成功了传递动力过程中平稳、噪音小、温升低、可高温高压消毒软轴;(3)创新点3:发明了颅骨钻手机内置行星齿轮传动机构和实现了颅骨钻头的钻穿即停功能,使得颅骨钻孔手术的有效和安全得到了保障。(4)DK-2000A手术动力系统操作简便,高效快速。所有连接均采用快速手工装卸,减小手术中繁琐的操作,对颅脑外科手术的急救、减小医生疲劳度和降低手术风险具有重大意义。本论文研究开发的手术动力装置技术已经过大量临床实践,证明设计成品的有效性及可靠性能够满足临床手术要求,得到了市场的验证与肯定。更多还原

【Abstract】 The operation power device is a necessary appliance in neurosurgery operation, which main function is to deal with the bone tissue in skull and rachis operation by drilling milling grinding and sawing. In recent years, our clinic medicine developed rapidly, especially the advanced aspect in medicine such as neurosurgery development, firstly, the prevalence of neurosurgery operation is improved, (most county hospital can do neurosurgery operation nowadays) secondly, the subtly and complexity of neurosurgery operation improved greatly. Therefore, it will stimulate the greater demand; on the other hand, it will bring forward more requirements of technology and quality in operation power device.From the analysis of practical situation of market, most advanced operation power device depends on import in domestic market. Today, many consumers are still use the traditional apparatus to operate, such as wooden drill and hand-rock drill. It will cause intensive labor force and high risk in operation, meanwhile, the spending of mass foreign exchange is unavoidable, so, it is necessary the current status. In this situation, the author bring forward the research and development of DK Surgical Power Device, and take the key part as the thesis of PH.D.The operation power device is a comparatively complicated system, which involved many technologies such as exactitude machinery transmission, material, soft and hard ware and electric control biomedical. But this essay can’t illustrate clearly because of the restriction of space, so, the author choose the flexible shaft, drill handset and reliability of mainframe caloric as the key research objects which have a great affection on the realization of product function and the operation safety.There are two circumstance of the operation power device used in neurosurgery. The first one is open skull, (drilling of skull and cutting), it has a strong requirement of power but lower demand of speed. The second one is the burnishing of bone structure of skull bottom or spinal column, it has a strong requirement of speed but lower demand of power, and the small size of handset. The operation power device can divided into two categories, flexible shaft driving and micro-computer driving, both of the two categories have its own advantages and disadvantages. The flexible driving system adopt the alternating current electric motor, it has a strong power and can satisfied the skull-open operation better, the disadvantages of the system is the lower speed of achievable terminal output (generally less than 20000r/min), and the big size of handset assembly, it cannot satisfied the skull-bottom and spine operation with the requirement of high speed and small size. But the micro-computer driving system is the different one, it has the technical characteristic of high speed and small size, which can satisfied the skull-bottom and spinal operation with the requirement of high speed and small size, but the disadvantages of the system is the lower power (generally only decades tile), which is very difficult to do skull-open operation. The traditional product of operation power device only has one working pattern, therefore, it has difficulties in satisfied the burnishing requirement of skull-open, skull-bottom and spine operation coinstantaneous in clinic applying. So, the demand to develop operation power system which can meet the operation requirement of skull-open, skull-bottom and spine is formed. The author solves the problem commendably by combine the flexible shaft driving system and the micro-computer driving system to one device creatively. The combination of the two ways make it is more complicated in the control of mainframe, and formed a new problem of reliability of mainframe heat. On the basis of research, the problem solved commendably. And as the key parts of the operation power device such as flexible shaft, drill handset and drill bur, the capability of librations, radiation, plasticity, noise, weight and size has a great affection to the function and security of operation power device.On the basis of lucubrating correlation technique of neurosurgery operation power apparatus and the status of product status, integrated biomedical engineering with mechanics, materials science, dynamics, electronics, modern control theory and computer science, this thesis propound two ideas. One is neurosurgery operation power apparatus based on flexible shaft transmission and brushless micromachine drive, the other is actualization of encephalic OPS safety protection based on reliable drilling-out protection, precision OPS, antisepsis and high output torque. Therefore, the task of this thesis is to develop our research turned on the hard cores of operation power apparatus mentioned above, while we will use the modern CAD/CAE technic to accomplish design and circular analysis, improvement.Following is the main R&D work:(1) according to the performance requirement of flexible shaft transmission, detailedly analyzed the dynam and performance of the subassembly, formated dynamics model, profounded the rigidity and the intension of buckling strength, torsion resistant, proposed computational theory of parameter above and finally trial-manufactured up to standard. (2) Adopted finite element method to analyze dyn and static’s index of joint construction part such as coupling spindle. Actualize optimal design of transmission attaching parts. (3) Design and optimize the technical proposal of epicyclic gear’s transmission system for fulfilling craniotomy requirement of great power. (4) Adopted nonhomogeneous rational B-spline curve approximation technic to construct gear form, Using the geometry methods of structure entity to format parameterized characteristic model of epicyclic gear’s transmission system and parts, Applying finite element technic to emulate, analyze and optimize the stress and movements of these important power transmission components. Designed and developed Energizing machines, which have enough intensity, dyn, transfer performance, low noise, stabilization, and of which reduction ratio is 1:6. (5) The power and heat dissipation of host computer’s interior electric components are higher, so this thesis adopted finite difference method to research control by volume, numerical simulation analyzing mainframe box’s three dimensional structure heat conduction and fluid flow. Optimize parts layout and parameter of fanThrough the research of the key technic above, make DK-2000A operation power apparatus which is the object of this thesis have these nice performance:(1) Integrate great power with micro-power, can synchronously use two power transmittal mode: Flexible shaft driving and micro motor driving. Optimally match the function and the approach, applying to the neurosurgery OPS that require great power for drilling, milling, high-speed polishing and grinding tiny hole. (2) Improving safety performance, the processing of flexible shaft transmission is stable, low noisy. And can be sterilized in the 135℃steam, cranial drilling handle with epicyclic gear transitive mechanics can transfer the more torque, cranial drilling bits can be stop when cranial bones is drilled through. All of these give a guarantee to operation of cranial drilling and the more power.(3)facility of operating and maintenance, all of joint and fixing are finished by hand without special tolls, it is important to emergency treatment for nuerosurgiery and reducing doctor’s tiredness and danger. (4) work for 40 minutes without interruption. Utilization ratio is improved because of treating several patents and the more difficult operation.The practice of clinical medicine shows that the mechanical transmission Components of DK-2000A is excellent, secure and stable and suitable to applying to treatment of drilling, milling, grinding for cranial bone in the fields of nuerosurgery and replace imported product. Up to now, all of the mechanical transmission Components has been practiced in clinical medicine. The stability and security of the Components have been fully affirmed by market.更多还原