689 results about "Pulse magnetic field" patented technology

An apparatus for creating pulse magnetic stimulation, having a modulation function, according to the present invention, comprises: a driving voltage supplying section for converting AC voltage input from a voltage source into DC voltage having a predetermined magnitude; a capacitor section for accumulating electric charge in accordance with the DC voltage; an input switch section for controlling the accumulation of electric charge in the capacitor section; a coil for generating magnetic flux in accordance with current generated by both-end voltage corresponding to the electric charge accumulated in the capacitor section; an output switch section for controlling discharge of the electric charge accumulated in the capacitor section through the coil; and a shunt switch section for lowering magnetic energy stored in the coil and voltage stored in the capacitor section into a ground level to obtain a pulse magnetic field. In this pulse-magnetic-stimulation creating apparatus having a modulation function according to the present invention, it is possible to efficiently transfer energy on the basis of current compliance of a patient and impedance of biologic tissue for therapeutic applications.

A magnetic control system for selectively enabling / disabling an implantable device's operation using externally applied pulsed magnetic means, e.g., a controlled electromagnet or the like. Typically, such implantable devices stimulate a neural pathway or muscle and / or block pain or muscle stimulation according to programmable settings. Preferably, once programmed from an external programmer, such implantable devices can operate “independently” using the externally provided programmed information. However, in certain circumstances, it may be desired to stop / pause the operation of such selected implanted device while not affecting other such devices. Accordingly, embodiments of the present invention include a magnetic sensor, preferably a magnetoresistive, Hall effect, saturated core reactors, or the like, to sense an externally provided magnetic field. By externally applying pulsed magnetic fields in sequences of controlled polarities, durations, intensities, etc., and sensing these identifiable sequences and transitions, the operation of the implantable device may be enabled / disabled.

This is a new invention, including improvements upon existing inventions, which is safer, simpler to use, less invasive into a user's daily routine and provides a lower cost solution to existing pulsed magnetic field and related vibrational electromagnetic therapy devices. This invention (apparatus) is referred to as an EnergyWave Therapy Device to distinguish it from existing electromagnetic therapy devices. It operates non-invasively on a homeopathic level to improve sleep, encourage natural healing and reduce pain, swelling, and general discomfort. This is accomplished through different embodiments of the apparatus all of which generate Multiple Simultaneous Extremely Low Frequency (MSELF) energy waves which may be any combination of Alternating Polarity Magnetic Fields (APMF), narrowband near-coherent long-wavelength (580 nm to 980 nm) light emitting diodes (LEDs), or electrical vibrations transmitted through the medium of water using carbon rod electrodes. The MSELF vibrations are derived from a quartz crystal with a fundamental frequency less than one-half of one percent from a natural Fibonacci Sequence Number. The apparatus utilizes firmware operating in a microcontroller containing predefined, user selectable therapy programs either emulating natural Circadian Rhythms for sleep and rest, or other therapeutic programs, all of which contain Electromagnetic Field (EMF) dose limitations to prevent any possible overexposure. The microcontroller is also clocked at the same fundamental frequency generated by the Fibonacci Sequence Quartz Crystal. Additionally, the apparatus's unique application of an H-Bridge configuration power-driver with Pulse Width Modulation (PWM) capabilities supports a novel approach to supply two simultaneous therapeutic frequencies to either a copper-trace coil emitter integrated on the main Printed Circuit Board (PCB) or optional external energy emitters. The result is a more effective, lower energy, safer, lower cost, simpler to use, noninvasive, multi-modal, EnergyWave Therapy Device.

Magnetic field sensors have a magnetic field sensing element and also a feedback circuit to provide a gain-adjustment signal to affect a sensitivity associated with the magnetic field sensing element. In some arrangements, the feedback circuit can include piezoresistors to sense a strain of a substrate over which the magnetic field sensor is disposed. With these arrangements, the feedback circuit can generate the gain-adjustment signal in accordance with the sensed strain. In other arrangements, the feedback circuit can generate pulsed magnetic fields proximate to the magnetic field sensing element in order to directly measure the sensitivity of the magnetic field sensing element. With these arrangements, the feedback circuit can generate the gain-adjustment signal in accordance with the sensed sensitivity.

A device for treating diseases and chronic ailments of the human body by inducing powerful, short duration magnetic pulses in close proximity to a region of the body. The device comprises an electromagnetic coil or inductor energized by an electric circuit and a power source, pulsed between 1 and 25 pulses per second for therapeutic means and use as an alternative medical treatment. The device comprises an electric circuit that transmits pulsating current to an induction coil placed within a handheld stylus device for introducing a high energy, pulsed magnetic field to target locations on the body. The stylus is placed against the human body and introduces the pulsating magnetic field into and through body tissue, bone and the bloodstream. The stylus is completely noninvasive and provides a means to direct magnetic energy to a specific part of the body. The device is an advancement in the art, and one that provides increased magnetic energy and pulse frequency without the use of Xenon flash tubes that consume large quantities of power.

The invention relates to a method for preparing endogenetic particle reinforced metal matrix composites under the coupling effect of a magnetic field and supersonic waves. The method comprises: adjusting the temperature of a metal matrix fused mass to the reaction initial temperature after refining, adding a reactant which can generate a particle phase with the fused mass through the reaction in situ for implementing the synthesis reaction, standing the mixture after the reaction is over, and cooling the mixture to the pouring temperature for pouring; and the method is characterized in that: the magnetic field and the high-intensity ultrasonic field are simultaneously exerted in the reaction synthesis process to realize the synthesis of endogenetic particle reinforced metal matrix composites under the coupling effect of the magnetic field and the high-intensity ultrasonic field. The magnetic field can be an intense pulse magnetic field, a high frequency oscillation magnetic field or a low frequency alternating magnetic field. In the method, the coupling effect of the magnetic field and the ultrasonic field makes the particle sizes be thinned and dispersed evenly; the ultrasonic vibration agitation and electromagnetic stirring functions improve the composite dynamic condition, and the compounding of the particle phase and a base metal interface is better; and the co-action of magnetochemistry and sonochemistry improves the thermodynamic condition of the reaction in situ, as well as speeding up the reaction in situ and controlling the growth of the particle phase.

Electrocrushing drills and methods for operating electrocrushing drills. Electrocrushing drill bits comprise one or more high voltage electrodes surrounded by a ground or current return structure, which can be a ring or a comprise rod shaped electrodes. Openings in the rim of the current return structure facilitate removal of drilling debris and bubbles created by the electrocrushing process out from the bottom face of the bit and up the wellbore. The high voltage electrodes can be arranged in a circle. The current return structure may partially cover the bottom face of the drill bit, thereby enclosing the high voltage electrodes in openings that may be sector shaped. The drill may comprise one or more conducting loops, in each of which pulsed current creates a pulsed magnetic field. The loops can be oriented in particular directions to provide a pulsed magnetic field with the desired configuration and orientation in space. The formation ahead of the drill can then be evaluated with the appropriate sensors.

Magnetic field sensors have a magnetic field sensing element and also a feedback circuit to provide a gain-adjustment signal to affect a sensitivity associated with the magnetic field sensing element. In some arrangements, the feedback circuit can include piezoresistors to sense a strain of a substrate over which the magnetic field sensor is disposed. With these arrangements, the feedback circuit can generate the gain-adjustment signal in accordance with the sensed strain. In other arrangements, the feedback circuit can generate pulsed magnetic fields proximate to the magnetic field sensing element in order to directly measure the sensitivity of the magnetic field sensing element. With these arrangements, the feedback circuit can generate the gain-adjustment signal in accordance with the sensed sensitivity.

Nanopowder synthesis systems in which a pulsed magnetic field is applied to electrodes of precursor material, in close proximity to an electrical discharge arc that is formed between the electrodes, to attain increased yields of nanopowder. A magnet insert of a coating precursor material is used to coat the nanopowder and thereby reduce nanoparticle agglomeration.

An apparatus for increasing the ability to detect ferromagnetic objects by increasing the magnetization of the objects. The apparatus includes at least one coil to generate a magnetic field positioned in the area of the object to be detected. The apparatus includes an electrical energy storage capacitor bank capable of quickly releasing stored energy. The apparatus includes a high speed, high current electronic switch capable of quickly transferring the stored energy from the capacitor bank to the coil thereby producing in the coil a short duration, single polarity magnetic field pulse. The apparatus includes a sample and hold circuit capable of acquiring magnetic field sensor data during periods when the pulsed magnetic field is not present. The apparatus includes a microprocessor controller to control timing and sequence of the magnetic pulse generation and the sensor data sample and hold process. The apparatus may be for portal handheld or head mounted applications.

The invention discloses a device and a method for the self-piercing riveting of a half-hole rivet loaded by a pulse magnet field force, which relate to the device and the method for the self-piercing riveting of the half-hole rivet and aim to solve the problem that a conventional punching self-riveting process has the problems of complex riveting process, bad riveting quality and low efficiency in the pre-punching of a riveting component. A punch head is arranged below a stress wave modulator; a female die is arranged under an electromagnetic riveting gun; a control box controls the on / off of an electromagnetic riveting charging switch of a low-voltage electromagnetic riveting device and is connected with the signal input end of a high-voltage pulse generator of the low-voltage electromagnetic riveting device; and the signal output end of the high-voltage pulse generator is used for controlling the on / off of a high-frequency thyristor discharging switch of the low-voltage electromagnetic riveting device. The method comprises the following steps that: firstly, a capacitor bank is charged; secondly, a discharging loop is switched on and the capacitor bank is discharged to apply the action of an axially downward pulse load to a driven piece; and finally, the stress wave modulator is amplified and acts on the half-hole self-punching rivet through the punch head to realize self-punching riveting. The device and the method are used for the self-punching riveting of a connected piece.

The invention discloses a high-strength and high-conductivity CuAg alloy material with a continuous fiber tissue and a preparation method thereof. The material consists of Cu, Ag, etc. Cu and Ag alloyingot with a columnar structure is obtained by a directional solidification technology, and continuous fibrous tissue structure is obtained by the technologies of extruding, drawing, etc. The components of the alloy material are as follows: 5-10wt% of Ag and balance of Cu. The preparation method of the CuAg alloy comprises the following steps: (1) preparing chemical composition; (2) vacuumizing asmelting room and a directional solidification room; (3) smelting the alloy; (4) directionally solidifying; (5) hot extruding; (6) hot processing; and (7) drawing wire or rolling. The material is applicable to slide contact material such as a middle-load and low-load switch, a breaker, a contactor, a micromotor slip ring, a commutating sheet, and the like, high-pulse magnetic field conductor material, an integrated circuit lead wire frame, a fish torpedo lead wire, an electric conduction reed, etc.

The invention relates to a high-speed steel roll and a preparation method thereof by centrifugal compounding in an electromagnetic field, belonging to the technical field of preparation of the high-speed steel roll. The components of a working layer material of the high-speed steel roll are as follows (in weight percent): 1.5 to 2.5 percent of C, 4.0 to 6.0 percent of V, 4.0 to 6.0 percent of W, 1.5 to 4.5 percent of Mo, 2.0 to 4.0 percent of Cr, 0.04 to 0.18 percent of Zr, 0.001 to 0.003 percent of B, less than or equal to 0.5 percent of Si, less than or equal to 0.5 percent of Mn, and the balance of Fe and impurity elements; and in the impurity elements, the required contents of S, P and O are respectively less than 0.01 percent, less than 0.01 percent and less than 0.0010 percent. The roll is cast by adopting a centrifugal compounding method in a pulse electromagnetic field, the frequency of the pulse magnetic field is 0.1 to 10Hz, and the peak strength of a central magnetic field of a cast mold is 1 to 10T. The roll has a plurality of precipitation strengthening phases, and the applied pulse magnetic field leads the strengthening phases and matrix crystal grains to be refined effectively and leads the strengthening phases to be distributed in a dispersed manner, thus overcoming the segregation of alloy elements and greatly improving the performance of the roll.

When a mechanical frame or gantry is used to move one or more electromagnets about a subject, the pulsed magnetic fields of the magnets need to be triggered, but only when the coil is in an appropriate physical position. Trigger points are established along the movement pathway (e.g., along the support frame) for the electromagnets that trigger the pulsation of the current being supplied to the given electromagnet. Use of the present invention allows firing of a magnetic coil to coordinate with the position of that coil, without need for expensive robotics or computerized motion control.

The invention relates to a method for reducing the residual stress of a ferromagnetic metal material. The method is to process the ferromagnetic metal material through a pulse current and a pulse magnetic field, wherein the processing time is 10 to 50 s; the density of the pulse current is 102 to 104 A / cm2; the action time of a single pulse is 0.1 to 50 ms; the number of the continuously input current pulses is 5 to 30; an interval between a process of continuously inputting 5 to 30 pulse current with the action time of 0.1 to 50 ms and a process of inputting 5 to 30 pulse current again with the action time of 0.1 to 50 ms is 3 to 5 s; the number of interval times of the whole processing procedure is 4 to 6; the pulse magnetic field is generated in an electromagnet mode; the exciting peak value current is 30 to 80 amperes; the output field strength is 0 to 2.25 T; the action time of a single magnetic pulse is 0.2 to 1 s and the interval is 0.2 to 1 s; and the magnetic pulse and the interval are performed alternatively until the whole processing procedure ends up. The method can obviously reduce the residual stress.

The invention relates to a weak magnetism detecting instrument based on time-resolved remanence relaxation detection and application thereof. The detecting instrument consists of a detecting unit provided with a sensitive element with high sensitivity therein, a sample bracket, a pulse magnetic field generator, a signal data acquiring and converting system and a computer. The working principle of the detecting instrument is that the superparamagnetic nanomaterial is magnetized via pulse by means of a pulse magnetic field with a steep edge, then a magnetism sensitive element with a high sensitivity is utilized to carry out track analysis on the remanence relaxation generated by the superparamagnetic nanomaterial under the action of the pulse magnetic field, and then a quantitative detection of superparamagnetic nanomaterial is realized. By means of the instrument, biological analysis with high sensitivity can be realized by combining with nano-particles or magnetic beads. The instrument and method of the invention have fast detection speed, low cost, high sensitivity and good stability, and are suitable for fields of biological analysis, disease diagnosis, food security, environment monitoring and the like.

The invention relates to a permanent-magnet and pulsed-eddy-current composite magnetic flux leakage detection method. With the method provided by the invention, defects on inner and outer surfaces can be effectively identified. The method belongs to the field of nondestructive test. With the effect of a permanent magnet, a ferromagnetic material requiring detection is magnetization into a local saturation state; if a detected magnetic flux leakage signal is larger than a preset intensity threshold B1, the ferromagnetic material has a defect; a reverse narrow pulse signal is applied to a excitation coil, such that the excitation coil generates a pulsed magnetic field, and pulsed eddy current is formed on the inner surface of the ferromagnetic material below two poles of a U-shaped magnetic yoke; at the time, if a detected leakage field intensity pulsation value is larger than a preset pulsation threshold B2, the defect is positioned on the inner surface of the ferromagnetic material; otherwise, the defect is positioned on the outer surface of the ferromagnetic material. The method provided by the invention has the advantages of simple hardware structure, low energy consumption, and convenient and fast signal processing.

The invention provides a magnetic-acoustic electrical impedance imaging method. The method is characterized by measuring a Lorentz force vibration displacement waveform signal generated under the action of a static magnetic field due to an inductive loop excited by a pulse magnetic field by using an acceleration sensor and acquiring an electric conductivity image of an imaging body through image reconstruction according to nonlinear relation between the displacement waveform signal and the electric conductivity. The device which adopts the method comprises a pulse exciter, exciting coils, a magnetostatic body, an acceleration sensor array, a data acquisition unit and a computer, wherein the exciting coils and the magnetostatic body are arranged on two sides of the imaging body; the acceleration sensor array are distributed surrounding the imaging body; the pulse exciter is connected with the exciting coils through cables; and the acceleration sensor array, the data acquisition unit and the computer are connected in turn.

The invention provides a method and a device for preparing high-performance aluminum-base composite material under the action of the pulsed magnetic field with the in situ crystallization method, belonging to the technical field of material preparation. The method comprises the following steps: smelting to synthesize compound material melt at the temperature of 10-200 DEG C higher than the compound material melt liquidus temperature and pouring the compound material melt into a specially-designed crystallizer to make the compound material melt solidify under the action of the pulsed magnetic field. The pulsed magnetic field has the key parameters of the pulse width of 1-500 ms and the amplitude strength of 0.1-50T. The pulsed electromagnetic force is applied to the process of solidifying the compound material melt under the action of the pulsed magnetic field so as to refine the matrix structure and the particle reinforced phase of the compound material at the same time, control the growth of the particle reinforced phase in cluster, increase the bonding strength of the interface of the particle reinforced phase and the matrix and obviously improve the performance of the composite material.

Disclosed is a dynamic and static magnetic pulse physical therapeutic apparatus which can provide an energy superposition field of dynamic magnetic pulses including mechanical vibration, a pulse magnetic field, a permanent magnetic field, thermal radiation and far infrared radiation and an energy superposition field of static magnetic pulses including a pulse magnetic field, a permanent magnetic field, thermal radiation and far infrared radiation, individually or at the same time. It includes a shell, a far infrared radiation fin with a heating device, a plurality of annular permanent magnets and a control circuit; a dynamic magnetic pulse assembly or a static magnetic pulse assembly is provided at the center of the annular permanent magnet. The massage to the human body with a dynamic magnetic pulse energy field and a static magnetic pulse energy field of synchronous frequency makes the main and collateral channels of different parts of the human body receive synchronous massages of different forms and thus have obvious functions and improved curative effects on main and collateral channels deroppilation, activating blood and absorbing clots.

Cross-well electromagnetic (EM) imaging is performed using high-power pulsed magnetic field sources, time-domain signal acquisition, low-noise magnetic field sensors, spatial oversampling and super-resolution image enhancement and injected contrast fluids. The contrast fluids increase the electromagnetic character of the formation and fluids, either the magnetic permeability or the dielectric permittivity. The acquired signals are processed and inter-well images are generated mapping electromagnetic (EM) signal speed (group velocity) rather than conductivity maps. EM velocity maps with improved resolution for both native and injected fluids are provided.

The invention discloses a preparation method of highly pure quartz sands. The method comprises the following steps: 1, roughing: cleaning a raw material, and crushing the cleaned raw material; 2, carrying out calcining and water quenching: calcining the crushed raw material, taking out particles, and quenching the particles in an ice-water mixture; 3, carrying out electric separation and magnetic separation: milling the quenched particles, carrying out electric separation and magnetic separation twice, and carrying out pulse magnetic field treatment; 4, pickling: immersing a material obtained in step 3 in a hydrochloric acid solution, filtering the immersed material, dialyzing the obtained first filtrate to recover hydrochloric acid, preparing a first mixed acid by using the recovered hydrochloric acid and a sulfuric acid solution, immersing quartz sands in the first mixed acid, filtering the immersed quartz sands, dialyzing the obtained second filtrate to obtain recovered mixed acid, preparing a second mixed acid by using the recovered mixed acid and a nitric acid solution, immersing the quartz sands in the second mixed acid, adding the immersed quartz sands to a sodium carbonate solution, and flushing the quartz ands; 5, floating the flushed quartz sands; and 6, drying the floated quartz sands. The preparation method allows highly pure quartz sands with the SiO2 content to be not lower than 99.995% to be produced, and takes a greatly lower acid amount than traditional methods.

The invention discloses a method for repairing micro-defects inside metal materials which can repair the micro-defects inside the metal materials so as to improve the performance of the metal materials without affecting the thermal deformation of the metal materials. The method comprises the following steps: putting the metal material to be repaired in an external physical field excitation device capable of generating a pulsed magnetic field and a pulsed electric field, and selecting the appropriate field treatment process for processing according to the magnetic property of the metal material and the configuration type of the microscopic defect inside the substrate. In this way, the in-situ repair of internal defects of metal materials can be realized by pulsed magnetic field and pulsed electric field induction. Therefore, the plastic toughness of metal materials is improved, the strength of materials can be increased, the abrasion resistance of materials can be greatly improved, the initiation of microcracks can be restrained and expansion of the microcracks can be delayed, and the fatigue life of the materials can be significantly prolonged. In addition, the whole repair process will not cause significant temperature rise and thermal deformation of the metal material.

The invention discloses a pulsed high magnetic field auxiliary laser welding method and device. The method and device can be applied to laser spot welding and seam welding. According to the method, in the overall welding process, laser beams are emitted to a workpiece to form a welding connector, a high pulsed magnetic field is exerted to the welding connector which is just solidified and the surrounding area, the pulsed magnetic field generates pressure stress on the surface of the workpiece to enable the connector area to have plastic deformation, residual stress is released to lower the degree of stress concentration and the degree of structural deformation of the welding connector, and the fatigue strength of the welding connector is improved. The device comprises a laser, a pulsed magnetic field generator, a numerical control system, an optical transmission system and a laser pulsed magnetic field composite processing head. The processing head is used for integrating the laser beams and the high pulsed magnetic field, and regulating the perpendicular distance between an electromagnetic conversion device and the surface of the workpiece and the horizontal distance between the electromagnetic conversion device and the laser beams. By means of the pulsed high magnetic field auxiliary laser welding method and device, structural deformation can be lowered, welding quality and processing efficiency are improved, and the processing effect which is superior to that of an existing laser welding process is achieved.

Cross-well electromagnetic (EM) imaging is performed using high-power pulsed magnetic field sources, time-domain signal acquisition, low-noise magnetic field sensors, spatial oversampling and super-resolution image enhancement and injected magnetic nanofluids. Inter-well images are generated mapping electromagnetic (EM) signal speed (group velocity) rather than conductivity maps. EM velocity maps with improved resolution for both native and injected fluids are provided.

A method and a device suitable for implementing this method for etching a substrate (10), a silicon body in particular, using an inductively coupled plasma (14) are proposed. For this purpose, a radio-frequency electromagnetic alternating field is generated with an ICP source (13), the alternating field generating an inductively coupled plasma (14) of reactive particles in a reactor (15). The inductively coupled plasma (14) arises by the action of the radio-frequency electromagnetic alternating field on a reactive gas. Furthermore, a device is provided with which a plasma power injected into the inductively coupled plasma (14) via the radio-frequency electromagnetic alternating field with the ICP source (13) is capable of being pulsed so that at least from time to time a pulsed radio-frequency power can be injected into the inductively coupled plasma (14) as a pulsed radio-frequency power. In addition, the pulsed plasma power can be combined or correlated with a pulsed magnetic field and / or a pulsed substrate electrode power.

A method for estimating a property of subsurface material includes extracting a sample of the material using a downhole formation tester and performing a plurality of nuclear magnetic resonance (NMR) measurements on a sensitive volume in the sample where each measurement in the plurality is performed in a static homogeneous magnetic field with a pulsed magnetic field gradient that is different in magnitude from other NMR measurements to provide a waveform signal. The method further includes transforming each received waveform signal from a time domain into a frequency domain and comparing the frequency domain signal to a reference to provide proton chemical-shift information related to a chemical property of one or more molecules in the sample and transforming the frequency domain signals into a complex number domain that quantifies waveform signal amplitude changes to provide one or more diffusion rates with each diffusion rate being associated with a corresponding frequency.

A pulsed magnetic field is generated by a device having a magnet to be operated in pulse operation which contains at least one superconductive refrigerant-free winding that is disk-shaped or saddle-shaped. Also included is a refrigerating unit which has at least one cold head. A line system, having a refrigerant circulating in it according to a thermosiphon effect, thermally couples the winding to the cold head. The line system has a plurality of separate pipes lying next to one another. The pipes, open onto a common refrigerant distributor and closed at the other end, are thermally coupled to the surface of the disk-shaped or saddle-shaped winding.

An electromedical device (100), comprising: a depression chamber (265) provided with an opening (270); aspirating means (105) connected to the depression chamber (265); a pair of rollers (240) suitable for at least partly delimiting the opening (270) of the depression chamber (265); motor means (285) suitable for rotating the rollers (240); a generator (325) of pulsed electric current; and an electromagnetic transducer (320) connected to the generator (325) such as to transform the pulsed electric current into a pulsed magnetic field, the electromagnetic current (320) being configured such that the flow of the pulsed magnetic field crosses the opening (270) of the depression chamber (265).

The invention discloses a magnetic concentrator structure for magnetic pulse formation, which relates to a device for forming and connecting a metal pipe by using a pulse magnetic field force. The included angle between the side end face and the axis of a conventional magnetic concentrator structure is between phi / 6 and phi / 2, so energy transfer efficiency and energy concentration efficiency of the magnetic field are low. The invention provides a novel magnetic concentrator, the longitudinal section structure of which is transverse H-shaped; the value of the oblique angle of the side end face of the magnetic concentrator structure depends on that the structure remarkably improves the magnetic field energy in a magnetic pulse formation discharge process so as to improve the energy conversion efficiency of the magnetic concentrator, further prolong the service lives of a coil and the magnetic concentrator, reduce the discharge voltage and the like.