Abstract: The disclosure provides a development roll for electrophotographic apparatuses. The development roll for electrophotographic apparatuses includes: a shaft; an elastic layer formed on an outer circumferential surface of the shaft; a surface layer formed on an outer circumferential surface of the elastic layer; and an end protection layer formed on an outer circumferential surface of the surface layer at both ends in an axial direction. The end protection layer contains a binder polymer and a surface modification agent that has a cyano group.

Abstract: The disclosure provides a development roll for electrophotographic apparatuses. The development roll for electrophotographic apparatuses includes: a shaft; an elastic layer formed on an outer circumferential surface of the shaft; a surface layer formed on an outer circumferential surface of the elastic layer; and an end protection layer formed on an outer circumferential surface of the surface layer at both ends in an axial direction. The end protection layer contains a binder polymer and a surface modification agent that has a cyano group.

Abstract: Provided is a development roll for electrophotography devices in which image defects are suppressed and which achieve both maintenance of high charging properties and discharging properties. The development roll is provided with a shaft member, an elastic substance layer formed on the outer circumference of the shaft member, an intermediate layer formed on the outer circumference of the elastic substance layer, and a surface layer formed on the outer circumference of the intermediate layer. The volume resistivity of the surface layer 18 is within the range of 1.0×1014 to 1.0×1020 ?·cm, and the volume resistivity of the intermediate layer 16 is within the range of 1.0×107 to 1.0×1013 ?·cm.

Abstract: Provided is a development roll for electrophotography devices in which image defects are suppressed and which achieve both maintenance of high charging properties and discharging properties. The development roll is provided with a shaft member, an elastic substance layer formed on the outer circumference of the shaft member, an intermediate layer formed on the outer circumference of the elastic substance layer, and a surface layer formed on the outer circumference of the intermediate layer. The volume resistivity of the surface layer 18 is within the range of 1.0×1014 to 1.0×1020 ?·cm, and the volume resistivity of the intermediate layer 16 is within the range of 1.0×107 to 1.0×1013 ?·cm.

Abstract: To provide an elastic roll for an electro-photographic apparatus that includes an elastic body layer having a low hardness and being excellent in fatigue resistance, and thus is resistant to fatigue, and to provide a method for manufacturing the same. An elastic roll 10 for an electrophotographic apparatus includes a shaft body 12, and a foamed elastic body layer 14 provided on an outer periphery of the shaft body 12, wherein the foamed elastic body layer 14 consists of a silicone rubber foamed body including a plurality of air bubbles 18 in its base material containing cross-linked silicone rubber and a reinforcement material, and wherein the foamed elastic body layer has a communication degree of 40% or more. It is preferable that the elastic roll 10 should further include a skin layer 14a in the foamed elastic body layer 14 on an outer peripheral side.

Abstract: To provide an elastic roll for an electro-photographic apparatus that includes an elastic body layer having a low hardness and being excellent in fatigue resistance, and thus is resistant to fatigue, and to provide a method for manufacturing the same. An elastic roll 10 for an electrophotographic apparatus includes a shaft body 12, and a foamed elastic body layer 14 provided on an outer periphery of the shaft body 12, wherein the foamed elastic body layer 14 consists of a silicone rubber foamed body including a plurality of air bubbles 18 in its base material containing cross-linked silicone rubber and a reinforcement material, and wherein the foamed elastic body layer has a communication degree of 40% or more. It is preferable that the elastic roll 10 should further include a skin layer 14a in the foamed elastic body layer 14 on an outer peripheral side.

Abstract: There is provided a charging member (1) capable of improving adhesion of an elastic layer (3) with a surface layer (4), which is used for an electrophotographic image forming device. The charging member (1) has a shaft body (2) having conductivity, the elastic layer (3) having conductivity which is formed along the outer circumference of the shaft body (2), and the surface layer (4) formed along the outer circumference of the elastic layer (3). The elastic layer (3) contains a rubber and a calcium carbonate having a spindle shape. The surface layer (4) is composed of a cured material of a composition containing a matrix polymer, a polyisocyanate having two or more isocyanate groups in a molecule, and a porous particle. The calcium carbonate in the elastic layer (3) exists more at a side closer to the surface layer (4) than at a side closer to the shaft body (2).

Abstract: The object of the present invention is to provide a conductive roll having high resistance to permanent set and high resistance to adhesion. The conductive roll 1 has a rubber elastic portion formed of a rubber material including a carbon-carbon double bond and exhibiting electric conductivity. The surface of the rubber elastic portion is exposed as the surface of the roll. An organic group including one or more groups selected from silicone groups and fluorine-containing groups is bonded through an isocyanuric acid skeleton to the surface of the rubber elastic portion. The organic group may be a group derived from an organic compound including one or more groups selected from silicone groups and fluorine-containing groups and having a carbon-carbon double bond.

Abstract: The object of the present invention is to provide a conductive roll having high resistance to permanent set and high resistance to adhesion. The conductive roll 1 has a rubber elastic portion formed of a rubber material including a carbon-carbon double bond and exhibiting electric conductivity. The surface of the rubber elastic portion is exposed as the surface of the roll. An organic group including one or more groups selected from silicone groups and fluorine-containing groups is bonded through an isocyanuric acid skeleton to the surface of the rubber elastic portion. The organic group may be a group derived from an organic compound including one or more groups selected from silicone groups and fluorine-containing groups and having a carbon-carbon double bond.

Abstract: An electrically conductive roll includes a center shaft, an electrically conductive elastic layer formed on an outer circumferential surface of the center shaft, and a resistance adjusting layer formed radially outwardly of the electrically conductive elastic layer. The resistance adjusting layer is formed of a rubber composition which includes a rubber material, a thermoplastic resin having crosslinkable double bonds, at least one electron-conductive agent, at least one ion-conductive agent, and at least one electrically insulating filler. The thermoplastic resin, the at least one electron-conductive agent, the at least one ion-conductive agent, and the at least one electrically insulating filler are included in the rubber composition in respective amounts of 3-40 parts by weight, 10-150 parts by weight, not greater than 2 parts by weight, and 20-80 parts by weight, per 100 parts by weight of the rubber material.

Abstract: An electrically conductive roll including a center shaft, an electrically conductive elastic layer formed on an outer circumferential surface of the center shaft, and a resistance adjusting layer formed radially outwardly of the electrically conductive elastic layer, wherein the resistance adjusting layer is formed of a rubber composition which includes a rubber material, a thermoplastic resin having crosslinkable double bonds, at least one electron-conductive agent, at least one ion-conductive agent, and at least one electrically insulating filler, the thermoplastic resin, the at least one electron-conductive agent, the at least one ion-conductive agent, and the at least one electrically insulating filler being included in the rubber composition in respective amounts of 3-40 parts by weight, 10-150 parts by weight, not greater than 2 parts by weight, and 20-80 parts by weight, per 100 parts by weight of the rubber material.

Abstract: In a channel quality monitoring device comprising a phase detector for phase likelihood data of an input PSK modulated signal, an accumulator for an accumulated phase likelihood datum during a predetermined time interval, a BER calculating circuit for calculating a BER by using the accumulated datum, and a judging circuit for judging a channel quality by the BER, a pitch detector detects in the PSK modulated signal a selected fading pitch for making the BER calculating circuit produce as the BER an instantaneous BER at a time at which the time interval ends. Preferably, the pitch detector comprises an RSSI circuit for RSSI's of the PSK modulated signal and a pitch selector for selecting the instantaneous fading pitch from a plurality of fading pitches detected in the RSSI's. The BER calculating circuit comprises a plurality of BER calculator in correspondence to predetermined fading frequencies, relative to which BER's are preliminarily empirically decided versus the accumulated datum.

Abstract: A modem LSI includes a combination of a first frequency divider, a first PLL circuit composed of a phase comparator, an LPF and a VCO, and a first select switch for selecting one of the first frequency divider and the first PLL circuit to provide a detection clock for a detector and a combination of a second frequency divider, a second PLL circuit composed of a phase comparator, an LPF and a VCO, and a second select switch for selecting one of the second frequency divider and the second PLL circuit to provide an operation clock for a roll-off wave generator and a clock regenerator, the first and second frequency dividers and the first and second PLL circuits each receiving a reference clock from a common oscillator installed outside the LSI.

Abstract: A battery use system for a battery-driven portable electronic equipment includes a first battery chargeable and serving as a direct power supply source, a second battery parallelly connected to the first battery through a switch, a voltage detection circuit for detecting an output voltage from the first battery, a consumption current detection circuit for detecting the state of the consumption current of the portable electronic equipment, and a switch control circuit for controlling open and close of the switch in accordance with an output from the voltage detection circuit and an output from the consumption current detection circuit. The switch is closed to charge the first battery by the second battery when the output voltage from the first battery becomes smaller than a predetermined value, and at the same time, the consumption current is sufficiently small.

Abstract: In a portable telephone set, an earphone cord is a flat cord. Therefore, it is difficult for the flat cord to be twisted, so that the tangling of the flat cord is avoided. The motion of the flat cord in which the flat cord is pulled out of a main body in operation and contained therein in non-operation is conveyed to an antenna, so that the antenna is extended out of the main body in operation, and the antenna is contained in the main body in non-operation. In the same manner, the motion of the antenna is conveyed to the flat cord.

Abstract: In a switched capacitor amplifier circuit of an offset cancellation type, a capacitor is arranged between a reverse input terminal of an operational-transconductance amplifier and a reference voltage. Only in an offset cancelling operation in which a first group of switches are on, the capacitor functions as a load of the amplifier. The capacitor hence does not exert any influence upon transfer of charge. With provision of the circuit, the phenomenon of oscillation is suppressed in the operation to cancel the offset voltage.

Abstract: A switched capacitor circuit includes a first capacitor (102) connected between first and second nodes (101, 103), a second capacitor (C.sub.1) connected between the first node and an intermediate node (M), and a third capacitor (C.sub.2) connected between the intermediate node (M) and ground. A group of m parallel circuits are connected between the intermediate node and the second node. Each of the m parallel circuits has a fourth capacitor (C.sub.V) and a switch (D.sub.V) for coupling it to ground or to the second node (103) depending on a corresponding one of m bits of an N-bit gain control signal. (N-m) parallel circuits are connected between the first and second nodes, each including a fifth capacitor and a switch for charging it depending on one of (N-m) bits of the N-bit gain control signal. A first sampling switch (S.sub.1) couples an input voltage to the first node (101) in response to the first phase of a two-phase clock signal and coupling the first node to ground in response to the second phase.

Abstract: A frequency synthesizer which can effect a high speed frequency hopping operation without causing deterioration in stability in phase and frequency in a phase frequency-locked condition and also in output spurious characteristic is disclosed. An output range controlling circuit clips the output voltage of a phase frequency to voltage converting circuit at a voltage corresponding to an input signal. The phase frequency to voltage converting circuit outputs a voltage corresponding to a pulse width inputted thereto from a phase frequency detector. A low-pass filter removes high frequency components of a signal inputted thereto. A voltage-controlled oscillator outputs a signal having a frequency corresponding to a voltage of a signal having passed through the low-pass filter. The phase frequency detector effects phase frequency detection between a reference signal and a signal obtained by frequency dividing the output of the voltage-controlled oscillator by an arbitrary value by a variable frequency divider.

Abstract: A doubling circuit for adjusting the duty ratio of an output signal automatically and implemented as a digital circuit. A variable delay circuit delays an input signal while an exclusive-OR (EOR) gate produces EOR of the output signal of the delay circuit and the input signal. The resulting output of the EOR gate has a frequency double the frequency of the input signal. A low pass filter (LPF) filters the output signal of the EOR gate to produce a means voltage thereof. An integrating circuit integrates a difference between the output voltage of the LPF and a reference voltage. The delay of the variable delay circuit is controlled by the output of the integrating circuit. As a result, the doubled signal from the EOR gate has the duty ratio thereof automatically adjusted.