-
公开(公告)号：US4079391A
公开(公告)日：1978-03-14
申请号：US629546
申请日：1975-11-06
CPC分类号： G03B7/085
摘要： The output of a bridge circuit which is unbalanced when the quantity of light falling on a light-sensitive element is less than or more than a predetermined light quantity is applied to a differential amplifier circuit whose output varies from a minimum amplitude to a maximum amplitude. The output of the differential amplifier is connected to a first and second threshold circuit whose threshold values are symmetrical to the output value of the differential amplifier when the bridge is in balance. The gain of the differential amplifier is adjusted so that the differential output signal has an amplitude exceeding the first threshold value and less than the second threshold value for variations of light within an allowable range. Within this range the first threshold circuit furnishes an output signal and the second threshold circuit does not. When the first threshold circuit does not furnish an output signal or if the second threshold circuit does, a pulse generator is energized whose pulses are counted by a counter which is controlled to energize the windings of the stepmotor controlling the diaphragm aperture in pairs in a predetermined sequence for opening and the reverse sequence for closing the diaphragm. The operation of the pulse generator and thereby of the motor is impeded when a switch furnishes a signal indicating that the diaphragm is fully open.
摘要翻译： 当落在感光元件上的光量小于或大于预定光量时不平衡的桥式电路的输出被施加到其输出从最小幅度变化到最大幅度的差分放大器电路。 差分放大器的输出端连接到第一和第二阈值电路，当桥接器平衡时，其阈值与差分放大器的输出值对称。 调整差分放大器的增益，使得差分输出信号具有超过允许范围内的光的幅度超过第一阈值且小于第二阈值。 在该范围内，第一阈值电路提供输出信号，第二阈值电路不提供。 当第一阈值电路没有提供输出信号或者第二阈值电路是否被激励时，脉冲发生器被激励，其脉冲被计数器计数，该计数器被控制以激励步进电机的绕组成对地以预定的方式控制隔膜孔 打开顺序和关闭隔膜的相反顺序。 当开关提供指示隔膜完全打开的信号时，脉冲发生器和电动机的操作受到阻碍。
-
公开(公告)号：US4050795A
公开(公告)日：1977-09-27
申请号：US663814
申请日：1976-03-04
摘要： A single operating switch replaces the main switch connecting the diaphragm control means to the battery and the release switch activating the film transport. All camera circuits are directly connected to the battery when the main operating switch is closed. An electronic switch is connected in series with the film transport motor and is closed only upon receipt of a control signal. In a first embodiment the control signal is furnished by a timing circuit after a predetermined time interval following the activation of the main operating switch. In a second embodiment the control signal is furnished by a NAND-gate which has a first input which receives a "1" signal while the diaphragm is being adjusted and a second input which receives a "1" signal while the electronic switch is open. The NAND-gate thus furnishes a "1" signal to the electronic switch causing it to be conductive at all times except when the initial adjustment of the diaphragm takes place.
摘要翻译： 单个操作开关代替将隔膜控制装置连接到电池的主开关和启动胶片传输的释放开关。 当主操作开关关闭时，所有相机电路都直接连接到电池。 电子开关与胶片传送电机串联连接，仅在接收到控制信号时才关闭。 在第一实施例中，在主操作开关激活之后的预定时间间隔之后，控制信号由定时电路提供。 在第二实施例中，控制信号由NAND门提供，该NAND门具有在调节隔膜时接收“1”信号的第一输入端和在电子开关断开时接收“1”信号的第二输入端。 因此，NAND门因此向电子开关提供“1”信号，导致其始终是导电的，除了当膜片的初始调节发生时。
-
公开(公告)号：US4037232A
公开(公告)日：1977-07-19
申请号：US324896
申请日：1973-01-18
申请人： Karl Wagner , Bernhard VON Fischern
发明人： Karl Wagner , Bernhard VON Fischern
IPC分类号： G03B17/20
CPC分类号： G03B17/20
摘要： Three electric lamps with different voltage-illumination thresholds are connected to be successively turned on to show exposure times by an electronic switch, such as a transistor, connected to a voltage divider composed of a photoconductor, exposed to scene light, and a resistor.
摘要翻译： 连接具有不同电压照明阈值的三个电灯，以通过连接到由感光体组成的分压器暴露于场景光的电子开关和电阻器等电子开关（例如晶体管）来显示曝光时间。
-
-
搜索结果
3 条记录 (耗时 0.018 秒)
