Abstract: A ring oscillator for circulating pulse edges of two types therein includes an even number of inverting circuits connected in a ring. Each of the inverting circuits is operative to invert an input signal and output an inversion of the input signal. One of the inverting circuits is a first start inverting circuit which starts an operation of inverting an input signal in response to a first control signal applied from an external input. One of the inverting circuits except the first start inverting circuit and an inverting circuit immediately following the first start inverting circuit is a second start inverting circuit which starts an operation of inverting an input signal in response to a second control signal.

Abstract: A pulse circulating circuit includes inverting circuits each for inverting an input signal and outputting an inversion of the input signal. A time of signal inversion by each of the inverting circuits varies in accordance with a power supply voltage applied thereto. One of the inverting circuits constitutes an inverting circuit for starting which is controllable in inversion operation. The pulse circulating circuit circulates a pulse signal therethrough after the inverting circuit for starting starts to operate. An input terminal subjected to an analog voltage signal is connected to power supply lines of the respective inverting circuits for applying the analog voltage signal to the inverting circuits as a power supply voltage fed thereto. A counter serves to count a number of times of complete circulation of the pulse signal through the pulse circulating circuit.

Abstract: A magnetic detecting circuit has a magneto resistance element which converts a change of magnetism detected into a signal. A plurality of these magneto resistive elements are provided on a plane, and are oriented on the plane in two opposite directions having angles, relative to a bias direction, having substantially equal absolute values. The placement in opposite directions allows the resistance values from the elements to change in approximately the same direction as the object moves, to allow a monotonic change in the bias magnetic field. The change of the bias magnetic field can be detected from the change of resistance values of the magneto resistive elements.

Abstract: A laser printer is provided with a photoreceptor drum for transferring a toner image formed on a peripheral surface thereof to a sheet by rotating. The photoreceptor drum is stored in a process kit. In order to removably secure the process kit, a space is provided in an upper portion of a main body of the laser printer. A pair of bearings is provided in the process kit along a rotation shaft of the photoreceptor drum. Further, a pair of substantially U-shaped guides is provided for removably supporting the respective bearings in a direction substantially perpendicular to the rotation shaft. In this arrangement, since the installation and removal of the process kit can be done from the position above the main body, both the bearings and the guides can be exposed. This permits the respective positions of the bearings and the guides can be easily recognized, thereby ensuring an easy installation and removal of the process kit.

Abstract: The object of the invention is to reduce the number of parts which are required for supporting a photosensitive drum in a photosensitive drum cartridge. Engaging bodies of supporting members are inserted through mounting holes of a cartridge main body. Supporting shafts are inserted into supporting shaft insertion holes formed on the sides of a photosensitive drum. When the supporting members are rotated, the side walls of the cartridge main body are fitted into gaps between flat plates and engaging pieces. The supporting members are positioned with respect to and fixed to the cartridge main body, whereby the photosensitive drum is supported in the cartridge main body.

Abstract: A digitally controllable oscillator is provided with a variable-frequency ring oscillator comprising an odd number of inverting circuits connected to each other in a ring. The frequency of the output signal of the ring oscillator is determined by a digital input signal specifying the frequency of the output signal of the ring oscillator. The number of times of circulation of a pulse signal through the ring oscillator is counted. A pulse generator generates a pulse signal upon the coincidence of the counted number of times of circulation of the pulse signal through the ring oscillator with a number corresponding to the digital input signal. A series of these operations is repeated to make the pulse generator generate pulse signals successively at a period corresponding to the digital input signal.

Abstract: A pulse phase difference encoding circuit provides a digital signal indicating a phase difference between a first input pulse and a second input pulse. The first input pulse is provided to and circulated in a ring signal delay circuit having a plurality of signal delay elements that are connected in series. Intermediate points between the delay elements provide delayed pulses having different delay times. Upon receiving the second input pulse, a selector selects one delay pulse provided by the delay element at which the first input pulse has arrived, and generates a digital positional signal indicating a position of the selected delay element. The number of rounds of circulation of the first input pulse in the ring signal delay circuit is separately counted. According to the number of rounds of circulation of the first pulse and the positional signal, the digital signal indicating the phase difference between the first and second input pulses is formed.

Abstract: The process kit is mounted on the apparatus main body from above. By the support frame, the photosensitive drum, main charger and cleaning unit are integrally supported to compose the process kit. At both ends of the support frame, handle members made of flexible resin or metal are provided. The handle members are furnished with fixing pawls for fixing the process kit to the mounting position of the apparatus main body by engaging with the fixing recesses provided at the apparatus main body side. When the process kit is lifted, since the both ends are securely supported and are kept in balance by both hands, the support state of the process kit may be always stable. Whether the process kit is installed securely in the mounting position may be judged easily. That is, any user without professional knowledge can accurately and easily install the process kit.

Abstract: A device for detecting pressure of a high temperature pressurized fluid. A sensing element having a diaphragm adjacent to one end and a lead wire outlet adjacent to another end in the longitudinal direction of a rectangular parallelopiped configuration of the sensing element including the diaphragm. Thus, the lead wire outlet is a predetermined distance from the diaphragm heated by high temperature fluid. This prevents the lead wire outlet and the other electrical assemblies from suffering deterioration or misoperation caused by high temperature. The reliability of the pressure detecting device can be improved.

Abstract: A magnetic detection device including at least one oscillator circuit having a magnetoresistance element which converts a change of magnetism detected into a digital signal and a comparator for comparing the digitalized oscillating frequency of the oscillator circuit with another digitalized oscillating frequency generated from another oscillating circuit by taking a ratio thereof or by detecting a phase difference between the pulse signals. Utilizing the magnetic detection device, the amount of change of magnetism can be stably detected with a high accuracy within a wide range of ambient usage temperatures.Also, a physical quantity detection device including the magnetic detection device which can detect any physical quantity with a high accuracy.

Abstract: A pulse phase difference encoding circuit provides a digital signal indicating a phase difference between a first input pulse and a second input pulse. The first input pulse is provided to and circulated in a ring signal delay circuit having a plurality of signal delay elements that are connected in series. Intermediate points between the delay elements provide delayed pulses having different delay times. Upon receiving the second input pulse, a selector selects one delay pulse provided by the delay element at which the first input pulse has arrived, and generates a digital positional signal indicating a position of the selected delay element. The number of rounds of circulation of the first input pulse in the ring signal delay circuit is separately counted. According to the number of rounds of circulation of the first pulse and the positional signal, the digital signal indicating the phase difference between the first and second input phases is formed.