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公开(公告)号：US5097495A
公开(公告)日：1992-03-17
申请号：US676609
申请日：1991-03-28
CPC分类号： A61B6/102
摘要： An X-ray apparatus has a motor for moving its components in different directions. A collision sensor is formed by a bladder attached to a component of the apparatus and deformation of the bladder produces a change in the pressure of air within the bladder. The bladder has an air vent to the atmosphere which can be sealed by operation of a valve. A pressure sensor produces two control signals when the pressure within the bladder exceeds first and second threshold levels respectively. The second threshold level is greater in magnitude than said first threshold level. The first control signal closes the valve and causes a motor control circuit to discontinue any application of electricity to the motor. The second control signal opens a switch through which electricity normally flows to the motor. A mechanism also is provided to simulate a collision by compressing the bladder to test the operation of the detection system.
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2.发明授权Method for reduction of acoustical noise generated by magnetic field gradient pulses 失效降低由磁场梯度脉冲产生的声音噪声的方法
公开(公告)号：US4680545A
公开(公告)日：1987-07-14
申请号：US688677
申请日：1985-01-04
IPC分类号： G01R33/385 , G01R33/20
CPC分类号： G01R33/385 , G01R33/3854
摘要： A method is provided for reducing acoustical noise generated when gradient coils which are part of a nuclear magnetic resonance (MR) scanner are energized by current pulses in the course of an MR study. The acoustical noise is due to vibrations of a fiber-glass coil form on which the coils are wound. The vibrations are excited by high frequency components in the squared-edged conventional current pulses. Significant noise reduction is achieved by shaping the leading and trailing current pulse edges to eliminate the objectionable high frequency components. Advantageously, the pulse edges can be shaped using sinusoidal and Bessel function waveforms. Another useful waveform for pulse shaping is a ramp function with rounded transition points.
摘要翻译： 提供了一种用于在MR研究过程中通过电流脉冲激励作为核磁共振（MR）扫描器的一部分的梯度线圈时产生的声音噪声的方法。 声音噪声是由于缠绕线圈的玻璃纤维线圈形式的振动引起的。 振动由平方边的常规电流脉冲中的高频分量激发。 通过对前导和后沿电流脉冲边沿进行整形以消除令人反感的高频分量，可以实现显着的降噪。 有利地，可以使用正弦和贝塞尔函数波形来形成脉冲边缘。 脉冲整形的另一个有用波形是具有圆形转换点的斜坡函数。
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公开(公告)号：US4235454A
公开(公告)日：1980-11-25
申请号：US957530
申请日：1978-11-03
申请人： Floyd L. Gray , Jerome H. Adam , Larry Susami , Rick A. Zamzow
发明人： Floyd L. Gray , Jerome H. Adam , Larry Susami , Rick A. Zamzow
CPC分类号： A61B50/10
摘要： A mobile medical diagnostic device having a mobility chassis with two supporting wheels and a central steerable drive wheel. The device has an electrical power steering system controlled by two synchronized handles operable by wrist action of an operator walking behind the device. The handles include a rotatable grip for controlling the velocity of the device. Advancing the grip actuates the throttle to the drive wheel and retarding the grip actuates a proportional electromechanical braking system. The device includes a proximity detector system which uses ultrasonic transducers to determine when an obstacle is within close proximity to the device, and to responsively and automatically actuate the brake system. The device has a stabilization system which automatically extends an outboard support on each side of the central wheel when the device is positioned for diagnostic analysis and automatically retracts the supports to facilitate mobility of the device.
摘要翻译： 一种移动医疗诊断装置，其具有具有两个支撑轮的移动性底盘和中央可转向驱动轮。 该装置具有由两个同步手柄控制的电动助力转向系统，该手柄可操作在操纵在装置后方的操作者的手腕动作。 手柄包括用于控制装置的速度的可旋转手柄。 推动把手将节气门驱动到驱动轮并延迟把手致动比例机电制动系统。 该装置包括接近检测器系统，其使用超声波换能器来确定障碍物何时位于非常靠近装置的位置，以及响应地和自动地致动制动系统。 该装置具有一个稳定系统，当该装置被定位用于诊断分析并且自动地缩回支撑件以促进该装置的移动时，该自动延伸在中央轮的每侧的外侧支撑件。
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公开(公告)号：US5056365A
公开(公告)日：1991-10-15
申请号：US531222
申请日：1990-05-31
IPC分类号： A61B6/10
CPC分类号： A61B6/102
摘要： A collision sensor specially adapted for a power driven x-ray imaging apparatus includes a face collision sensor and an edge collision sensor. The face collision sensor has two annular plates which are biased apart longitudinally by three flat springs which are equiangularly spaced apart around the perimeter of the plates. Three equiangularly spaced cables hold the plates in parallel planes with the springs prestressed and collapse to allow the plates to be compressed together. Two sets of three switches each reside at equal angular intervals between the plates, with at least one of the switches of the first set being actuated when any point across the face of the sensor has been moved a predetermined longitudinal distance. At least one of the switches of the second set is actuated when the point on the face of the sensor has been moved a further predetermined longitudinal distance. An edge collision sensor includes a closed air bladder which surrounds the face collision sensor and in which a vacuum is drawn. A collision occurring around the edge of the face collision sensor causes an increase in the pressure of the bladder. A first pressure sensor is actuated if the pressure increase exceeds a first predetermined amount. A second pressure sensor is actuated if an additional predetermined increase in pressure occurs.
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公开(公告)号：US4399550A
公开(公告)日：1983-08-16
申请号：US238910
申请日：1981-02-27
摘要： Curved X-ray filter elements are arranged circularly around a drum. Alternate circumferentially adjacent elements have different filtration properties. Diametrically opposite elements have the same properties. An X-ray source provides a sequence of alternate low and high energy X-ray beam pulses. A multicell X-ray detector produces X-ray attenuation data for each pulse and the data is switched to alternate memories. A drum drive motor is energized at power line frequency. A pinion on the motor shaft turns a gear. A lug that is mounted for angular adjustment on the gear drives the drum. A multiple blade shutter is also mounted on the gear for angular adjustment and rotation with the gear. The shutter alternately interrupts and restores a light beam to a photosensitive device which produces corresponding signal state changes or trigger signals. The signals are used to synchronize the low and high energy X-ray pulses, the filter element angular locations and memory switching with power line frequency.
摘要翻译： 弯曲的X射线滤光片元件围绕鼓圆周布置。 替代的周向相邻元件具有不同的过滤性能。 直径相对的元件具有相同的特性。 X射线源提供了一系列交替的低能量和高能量X射线束脉冲。 多单元X射线检测器为每个脉冲产生X射线衰减数据，并将数据切换到备用存储器。 鼓驱动电机在电源线频率下通电。 马达轴上的小齿轮转动齿轮。 安装在齿轮上进行角度调节的凸耳驱动滚筒。 多叶片快门也安装在齿轮上，用于与齿轮进行角度调节和旋转。 快门交替地中断并将光束恢复到产生对应的信号状态改变或触发信号的光敏装置。 这些信号用于同步低能量和高能量X射线脉冲，滤波器元件角位置和电源线频率的存储器切换。
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公开(公告)号：US4105920A
公开(公告)日：1978-08-08
申请号：US740574
申请日：1976-11-10
CPC分类号： G03B42/025
摘要： In a spot film device, the inner and main carriages for a film cassette are positioned with reversible servo motors. An x-ray grid is mounted on the bottom of the main carriage and a cross grid is mounted on tracks beneath the carriage such that the cross grid may be used or not used for fluoroscopy and both grids may be used for radiography. Field defining masks are also mounted for translating selectively with the carriage. Individual reversible servo motor drives are used to advance and retract the masks and cross grid. Means are provided for absorbing shock or negating drive system momentum when the masks or grid are stopped abruptly. Reduced power is applied to the mask and grid drive motors when the masks and grid reach their stops for holding them against their stops. A motor driven palpator cone, having unique driving and locking means is provided. Means are provided for loading and unloading cassettes from either the front or rear of the spot film device.
摘要翻译： 在点胶装置中，用于胶片暗盒的内部和主要支架用可逆的伺服电动机定位。 X射线格栅安装在主托架的底部，并且十字网格安装在滑架下面的轨道上，使得十字网格可以用于或不用于荧光透视，并且两个网格可以用于射线照相。 场定义掩模也被安装成与滑架有选择地平移。 单独的可逆伺服电机驱动器用于前进和后退面罩和交叉网格。 提供了当掩模或网格突然停止时吸收冲击或抵消驱动系统动量的装置。 当面罩和电网到达其停止点以将其挡住时，对面罩和电网驱动电机施加减小的功率。 提供了具有独特驱动和锁定装置的马达驱动的触发器锥体。 提供了用于从点胶膜装置的前面或后面装载和卸载盒的装置。
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