Abstract: A microscope apparatus includes an objective lens, an imaging lens, a pupil relay lens, and an image relay lens. The primary image of a specimen is formed between the imaging lens and the pupil relay lens, and the image of the pupil of the objective lens is projected between the pupil relay lens and the image relay lens so that a pupil modulator is disposed at the position of the projected pupil image. This arrangement makes it possible to produce pupil modulation, observe various specimens, and set the optimum position of an eyepoint.

Abstract: A phase contrast microscope including an illuminating optical system, a ring slit arranged at a pupil of the illuminating optical system, an imaging optical system, and a phase plate arranged at a pupil of the imaging optical system which is conjugate with the pupil of the illuminating optical system with respect to a specimen plane on which a specimen under inspection is placed. The phase plate is formed by a liquid crystal and a pair of transparent ring-shaped electrodes arranged on both sides of the liquid crystal. A voltage applied across the liquid crystal via the electrodes is changed such that a phase difference introduced by the phase plate is set to .+-..pi./2 to obtain a dark contrast image and a bright contrast image. A difference between these dark and bright contrast images is derived to obtain a phase contrast image having high contrast and resolution.

Abstract: The movement of a control sleeve in the circumferential direction is made to interlock with the movement of a timer piston to ensure that the control sleeve has a function of pre-stroke control. In order to interlock the movements of the timer piston and the control sleeve, they are linked with first through third link members and the control sleeve is caused to rotate in the circumferential direction at a specific ratio relative to the quantity of movement of the timer piston. In a fuel injection system provided with an actuator for adjusting the fuel force feed end by moving the control sleeve in the direction of the axis and an actuator for controlling the timing with which the cam lift begins, pre-stroke control can be achieved without requiring a separate actuator, with a simple mechanical structure.

Abstract: Inflow/outflow ports are provided in either one of a distribution member for distributing compressed fuel or a control sleeve which is externally fitted around the distribution member. Each of the ports includes a slit extending therefrom. At the other one of the distribution member and the control sleeve, an intake-cutoff hole that communicates sequentially with the inflow/outflow ports and a pilot port which communicates with the slits during part of the force feed period are provided. Since the fuel flows out through the slits during part of the force feed period, pilot injection can be more easily achieved prior to the main injection during low speed rotation and fuel is less likely to be diverted through the slits due to the constricting effect during high speed rotation so that only the main injection is performed.

Abstract: A prestroke controller 31 for an engine fuel injection pump 30 utilizes a magnetic coupling 26 and, by taking advantage of the fact that the secondary side (driven side internal magnet) of the magnetic coupling can be controlled to a desired position without being driven by force from a flyweight 11 on the primary side (driving side external magnet), not only secures speed timer characteristics but also provides a greater degree of freedom in determining the injection timing advance characteristic. The prestroke controller 31 includes the magnetic coupling 26 as a member of a displacement transfer section provided between the flyweight 11 and the timing control rod 6 and also includes an add-on device 36 for injection timing advance adjustment which can be engaged with or disengaged from the timing control rod 6 and is capable of controlling the prestroke independently of the magnetic coupling 26.

Abstract: A pilot injection controller and a method of controlling pilot injection quantity enable the quantity of fuel pilot-injected fuel by an internal combustion engine fuel injection system of the type in which the fuel delivery stroke for pilot injection is fixed to be maintained substantially constant irrespective of engine speed by controlling prestroke such that the utilized portion of a cam is shifted to a lower delivery velocity region thereof with increasing engine speed, the principle involved being that the quantity of fuel pilot-injected by a fuel injection system is proportional to the actual plunger delivery velocity and the fact that since the actual delivery velocity is proportional to the product of the cam velocity constant and the cam rotational speed the actual delivery velocity can be maintained substantially constant by increasing the cam velocity constant in the low speed region and decreasing the cam velocity constant in the high speed region.

Abstract: In a solenoid valve, a gap is formed between a solenoid, which includes a stator housed within a resin mold, and a retainer that secures the solenoid on a housing. The gap communicates with a armature chamber that houses the armature mounted on a front end of a plug valve. High-pressure fuel is charged from the fluid passage into the armature chamber and flows into the gap around the solenoid to apply even pressure to the periphery of the resin mold as well as to the intake end surface of the solenoid. This prevents deformation of the resin mold and, consequently, distortion of the intake end surface. Such distortion can also be prevented by internally fitting a protective plate made of a non magnetic body in the opening ends of the coil grooves formed in the intake end surface of the stator.

Abstract: A pilot injection control system for an internal combustion engine comprises a plurality of fuel injection nozzles, the valve-opening pressure of one of which (the reference nozzle) is set slightly higher than that of the other nozzles, means for detecting the pilot injection of the reference nozzle, and means for feedback controlling the pilot injection quantity of the reference nozzle based on the detected pilot injection. The system is able to effectively control the pilot injection of all nozzles by actually controlling the pilot injection of only one nozzle and can therefore be implemented at low cost.

Abstract: A fuel injection pump for an engine comprises a magnetic coupling 37 straddling a partition 36 for connecting a timing control rod 6 and a displacement transfer section 34 of a governor so as to enable efficient transfer of rotational force from the displacement transfer section to the timing control rod without need for an oil seal therebetween, and a prestroke controller for the fuel injection pump 131 includes an injection advance adjustment add-on device 136 for conducting prestroke control independently of the magnetic coupling and thereby provide greater freedom in establishing injection timing advance characteristics by enabling injection timing control in response to temperature or load and/or a safety mechanism 237 for ensuring operation of a governor mechanism 20 based on movement of a flyweight 11 even if the magnetic coupling should stick.

Abstract: A solenoid valve unit is provided in the middle of fuel supply path that leads to a compression space in an injection pump main body, and the fuel injection quantity is adjusted through the open and close control of the solenoid valve unit. In this fuel injection system, the plug valve is moved until it is seated on the valve seat during the preliminary injection that is performed prior to the main injection. An arrangement for leaking the fuel from within the compression space is provided in the injection pump main body and the time period during which the fuel in the compression space is leaked via the arrangement for leaking and the time period during which the fuel supply path is restricted with the plug valve being seated on the valve seat are combined to stabilize the movement of the plug valve. Consequently, an optimal small quantity is achieved for the preliminary injection that is nearly constant regardless of the rate of rotation of the engine.

Abstract: ABSTRACT A solenoid valve is provided in a fuel injection pump fuel supply path. A communication path communicates with each other an armature chamber, which accommodates an armature, and a spill chamber, which accommodates a head of a valve body and is connected to a lower pressure side. When high pressure fuel is spilt to the low pressure side, an orifice in the communication path reduces a high frequency pressure wave propagated from the spill chamber to the armature chamber, thus reducing deformation or corrosion of the solenoid in over a long period of use.

Abstract: A prestroke control device for a fuel injection pump includes at least one control sleeve slidably fitted on at least one plunger, a control rod engaging the control sleeve, the control rod extending perpendicularly to the plunger and rotatable about an axis thereof for varying an axial position of the control sleeve relative to the plunger to thereby control the prestroke of the plunger, and an actuator for rotatively driving the control rod about its own axis. A counterweight is movable in unison with rotation of the control rod for cancelling a rotating force generated by axial movement of the control sleeve and acting upon the control rod.

Abstract: An objective lens for optical disks comprises a first lens component and a second lens component and, when the distance on an optical axis from an entrance face of the first lens component disposed in a position farthest from an optical disk to the center of gravity of the objective lens is taken as gc, the overall length of the objective lens as .SIGMA. d, and the focal length as f, the following conditions are satisifed and any of surfaces of the lens components is configured as an aspherical surface:g c<.SIGMA.d<0.50.9<.SIGMA.d/f<2.2Thus, the use of the objective lens makes it possible to reduce the load to a driving device for moving the objective lens and to provide the driving device small in size and light in weight.

Abstract: A compact, large-aperture objective lens for the optical memory designed as a single-element lens having aspherical surfaces on both the sides thereof and favorably corrected aberrations, and an imaging optical system having a simple composition consisting of a collimator lens designed as a single-element lens having spherical surfaces and an objective lens movable along the optical axis, and so adapted as to allow very little degradation of performance when the objective lens is shifted.

Abstract: A fuel injection pump includes a reciprocating plunger and a control sleeve slidably fitted over the plunger, the prestroke of which is varied by vertical movement of the control sleeve. The control sleeve is provided at its upper end with a fuel discharge groove, through which the fuel contained in a fuel-pressurizing chamber is discharged after the end of injection. The control sleeve also has to pressure escape passage. A variation in the effective stroke allows the pressure of fuel contained in the fuel-pressurizing chamber to be selectively regulated by the pressure escape passage, thereby controlling the pressure of fuel to be injected.

Abstract: In a fuel injection apparatus for an internal combustion engine which has a fuel injection pump having a plunger and one control sleeve fitted on the plunger and capable of regulating both the fuel injection quantity and the timing of the beginning of fuel injection by the adjustment of the relative positional relationship therebetween, and a control unit for controlling the positional relationship in order to obtain the optimum fuel injection rate and fuel injection quantity, the apparatus comprises a detector for detecting any trouble occurring in the control system for regulating the position of the control sleeve and a limiting circuit for limiting the control operation by the control unit so that an excessive rise in the inner pressure of the cylinders in the internal combustion engine is prevented when the occurrence of the trouble is detected by the detector.