Abstract: An apparatus for driving a blood pump such as an artificial heart. The apparatus comprises a first pressure pulse generator, a second pressure pulse generator, a pressure detector for detecting the pressure produced by the first pressure pulse generator, a flow sensor for detecting the flow rate of blood passing through the pump, a selector device, and an electrical control unit. Normally, the first pressure generator is connected with the blood pump via the selector device. When the flow rate detected by the flow sensor decreases and the pressure detected by the pressure detector gets out of a normal range of pressures, the electrical control unit causes the selector device to disconnect the first pressure pulse generator from the blood pump and to connect the second pressure pulse generator with the blood pump.

Abstract: An apparatus for driving a blood pump such as an artificial pump. The apparatus comprises a pressure pulse generator for producing pressure pulses, a pressure detector for detecting the pressure produced by the pressure pulse generator, and an electrical control unit (ECU) consisting of a microcomputer. The ECU estimates the pressure range obtained after the pressure is switched from a positive value to a negative value or vice versa, from the pressure obtained before the pressure is switched. The ECU then compares the pressure obtained after the switch of the pressure with the pressure range to determine whether the pressure is abnormal or not.

Abstract: A system for driving a medical device includes a positive pressure source; a first electromagnetic valve connected with the positive pressure source; an negative pressure source; a second electromagnetic valve connected with the negative pressure source; and an electronic control for switching the first and second electromagnetic valves at a predetermined timing. The electronic control includes a setting circuit for setting the switching timing of the first and second electromagnetic valves to generate a setting timing signal; a switching arrangement for switching the first and second electromagnetic valves in response to the setting timing signal of the setting circuit; a memory having a plurality of operation modes for inhibiting the operation of the switching circuit at a predetermined ratio to a predetermined number of the setting timing signal; and switches for selecting one of the operation modes of the memory means.

Abstract: With a driving system being separated by a diaphragm into two sections, a predetermined pressure is applied to the primary side of the diaphragm using air and helium gas or the like is used on the secondary side of the diaphragm, so that the pressure on the primary side of the diaphragm is transmitted to an artificial heart or the like connected to the secondary side thereof. Independently of a control system for maintaining the output from a pressure sensor to a predetermined value at all times, a solenoid valve for directly providing a higher pressure produced by a compressor or the like at the given drive timing is provided in a pressure regulating system, thereby causing a sharp rise in drive of the diaphragm. In an operation mode for automatically exhausting air from the secondary side of the diaphragm, the higher and lower pressures are alternately applied to the secondary side with the primary side being subject to the lower pressure, thus replacing air by another gas.

Abstract: A magnetic field sensing device for sensing low levels of magnetic intensity is composed of a ribbon-shaped strip of amorphous magnetic material having at least one twist along the length thereof between the ends of the strip. Subsequent to imparting the desired number of twists to the strip, the strip is supported in the twisted condition. The device is capable of generating a pulse in response to the presence of an external magnetic field similar to the Wiegand wire effect.