A programmable microcomputer controlled load sensing system for maximizing the cleaning efficiency of particulate raw materials such as sand, gravel, rock, ores, etc. in a log washer by sensing the weight of the aggregate in the log washer tank and adjusting the angle of inclination of the tank for cleaning efficiency. The system includes a log washer tank pivoted at its lower end and supported by hydraulic cylinders at its upper end. A high/low pressure sensor detects changes in the weight of the load by changes in hydraulic fluid pressure communicated to the microcomputer, and raises or lowers the upper end of the tank when the programmed low or high pressure limits are exceeded through solenoid activated hydraulic valves.

1. Field of the Invention
The present invention relates generally to aggregate material cleaning systems. More specifically, the invention is a fully automatic, load sensing system for a log washer that is used for cleaning aggregate materials, such as rocks, gravel, sand, and ores to remove dirt and waste materials. The system hydraulically changes the angle of incline of the washer tank to ensure that the washer tank is properly loaded with the solids for efficient cleaning action.
2. Description of the Related Art
The related art of interest describes various washing and weighing apparatus, but none recognizes the washing inefficiency problem and none discloses the present invention. There is a need for log washer for washing sand, gravel, ores, and similar particulate material to maximize the cleaning action based upon variations in the weight of the load being cleaned. The problem exists because in conventional log washers the inclination angle of the washer tank is fixed, whereas the load fluctuates in weight. As a general rule, if the angle of incline of the tank is increased, production is decreased, but the cleansing action of the washer is increased. Currently, the only way to vary the angle of incline is by manually increasing or decreasing the height of the structure supporting the washer tank, a labor intensive process which involves temporarily shutting down the log washer while the supports are adjusted. Therefore, by automatically adjusting the incline of the washer tank according to the load of solids, adequate cleaning is accomplished to maximize the efficiency of the washing process. The related art will be discussed in the order of perceived relevance to the present invention. No art discloses the critical feature of automatically adjusting the incline of the washer or separator tank to adjust the weight of the solids load to the washer.
U.S. Pat. No. 3,807,558 issued on Apr. 30, 1974, to Alton B. Hamm describes an apparatus for separating lightweight debris from sand, gravel and logs comprising the flowing of water at a high velocity in a restricted flow path to one side of the rotating auger and rotating the logs. The granular and aggregate material is discharged into the water flow for removing unwanted lightweight debris prior to the movement of the granular material into the zone of operation of the auger of the sand screw or rotating logs of the log washer. The inclination of the apparatus is supported by fixed supports. The apparatus is distinguishable for requiring a restricted water flow path and fixed supports for its inclination angle.
Japan Patent Application No. 7-253340 published on Oct. 3, 1995, for Toshihiko Miyashita describes an apparatus which can automatically perform an aggregate washing step in a pivotal mixing container with a spout, and emptying the aggregate material and liquid. The washer apparatus has a pair of supporting legs on a stage, and a base pad that may be rotated via a pivotal shaft in a vertical direction by the supporting legs to empty the contents. The aggregate mixing container has a mixing blade within rotated by a first drive motor which rotates with the container. The second drive motor rotates the mixing container and the first drive motor. The apparatus is distinguishable for being limited to a rotatable emptying feature for a mixing chamber.
U.S. Pat. No. 4,234,415 issued on Nov. 18, 1980, to Enrique de Tuya Casuso describes an apparatus for separating mixed solids of different specific gravities by means of a liquid medium comprising a rotatable frusto-conical separation chamber having a lighter solid outlet at one end, and a heavier solid outlet at the opposite end. A pair of frusto-conical chamber may be utilized to separate solids of three different specific gravities. The apparatus is distinguishable for its structural difference and its different objective of separating mixed solids of at least two different specific gravities.
U.S. Pat. No. 5,868,256 issued on Feb. 9, 1999, to Maynard A. Teppo describes a rotary clay material refiner apparatus comprising a horizontal rotating drum into which clay material and water are fed. The clay material and water form a slurry which is agitated by lifters within the drum. A series of adjustable lifters with the drum refine the slurry by lifting aggregates and rocks out of the slurry and discharging them out of the refiner apparatus. The refined slurry exits the drum through an opening and further processed. The apparatus is distinguishable for being confined to a horizontal rotating drum and requiring two separation steps.
U.S. Pat. No. 2,489,161 issued on Nov. 22, 1949, to William Scholes describes a gravity liquid separator apparatus for the separation of unspecified granular or lump material, comprising a tank minus an outlet wall and the bottom inclined up from the deep feeding end, wherein the material is fed from the bottom of the deep end by a continuous belt passing through an opening with a trailing rubber fabric sealing flap or an inflated pneumatic tube to minimize leakage. A rotary scraper is positioned midway in the apparatus. The apparatus is distinguishable for requiring a rotating material transporting belt within the tank.
U.S. Pat. No. 2,336,991 issued on Dec. 14, 1943, to Chester I. Leveke describes an apparatus for removing dirt, clay, shale, coal, and the like material from gravel comprising an inclined elongated trough having a square cross-section, a substantially open top, a bottom gravel outlet in the forward end and a hopper, and a grave escape slot at the opposite end. A centered rotating cylindrical agitator has agitating blades and three portions of decreasing diameter to the outlet. The apparatus is distinguishable for lacking any adjustable inclination means.
U.S. Pat. No. 1,972,195 issued on Sep. 4, 1934, to Marmakuke J. Lacey, Jr. describes an ore washer apparatus for washing ores such as phosphates, manganese and iron or concrete aggregates containing clay, chips, and silt in a fixed inclined frame. The moving gear comprises 5 parallel chains bearing plow share blades rotating on 3 sprocket wheels to define a triangle as viewed from the side. The ores are added in the baffled rear end and pushed to the front end in water for discharging out of the water via a discharge throat. The apparatus is distinguishable for requiring an immovable fixed tank.
U.S. Pat. No. 1,695,021 issued on Dec. 11, 1928, to Samuel R. Puryear describes an apparatus for separating solids comprising a substantially rectangular inclined tank with an enlarged rear end and twin screws. The solids such as mud balls mixed with gravel, lignite, coal, shale, and shells are fed with water from a chute into the rear end of the tank. The lighter materials are flushed by water jets toward an adjustable weir and into a perforated conduit leading to a rear trough. The twin screws carry the heavier material up the inclined tank out of the water and into a delivery chute. The apparatus is distinguishable for requiring a rear separation trough and directional jets of water.
U.S. Pat. No. 2,025,841 issued on Dec. 31, 1935, to Charles H. Young describes an apparatus for washing gravel to remove shale, lignite, bark, water-logged wood, and coal comprising an inclined tank on a frame support, and having a pair of screw conveyors which accept the heavier gravel feed from a shallow pan which discharges the heavier material in the rear. The screw conveyors move the gravel through the water to an outlet. Jets of water are also supplied continuously upward through the mixture from a bottom located pipe. The apparatus is distinguishable for requiring a fixed support.
U.S. Pat. No. 4,448,678 issued on May 15, 1984, to Cecil C. Gentry describes an inclined treatment trough having a two-section conveyor screw consisting of a notched screw in the front and a helical screw. In the rear of the trough, crushed lignite is fed into a settling pool of water having weir in the rear wall covering an exiting stream, while above the stream waste tailings flow over the rear wall. Water is sprayed above the trough. The lignite product exits at the front portion of the trough. Fixed supports are illustrated to obtain the inclination angle of the trough. The apparatus is distinguishable for requiring a two-section conveyor screw and fixed supports for inclining the trough.
U.S. Pat. No. 1,609,652 issued on Dec. 7, 1926, to John L. McQueen describes a log washer apparatus comprising twin screws having intermeshing paddles with cutting edges for washing sand, gravel, ores, and manganese to remove clay, dirt and waste matter. The apparatus is distinguishable for requiring specific log washer screws.
U.S. Pat. No. 2,050,458 issued on Aug. 11, 1936, to Melvin Ovestrud et al. describes a wheeled apparatus for treating quarried rock or pit run gravel to produce aggregates for concrete construction work comprising, in sequence, an upper scrubber chamber (inclined downward) receiving the raw feed, a coarse and fine particle conveyor, and a dehydrator chamber with an endless conveyor belt. A screen at the end of the scrubber chamber filters the smaller particles that pass down a hopper to a crusher. The apparatus is distinguishable for requiring multiple separating elements and a crusher, and lacking any adjustment of the inclination of the scrubber chamber.
U.S. Pat. No. 2,324,549 issued on Jul. 20, 1943, to Paul L. Wigton describes a spiral ore pulp classifier apparatus comprising an upwardly inclined open tank on fixed supports being fed ore pulp into the tank having a pool of water and a spiral conveyor. The pool end of the tank has an upper outlet for slime and a bottom outlet for a drain. Sand is discharged from the front end. The apparatus is distinguishable for requiring a fixed inclination.
U.S. Pat. No. 5,992,776 issued on Nov. 30, 1999, to Gianni B. Arcaini et al. describes a process for processing ash from the mass burning of municipal waste utilizing various apparatus comprising a shear-force shredder for the size reduction of bulky items, impact cleaning of ferrous metal items, and a rotary washer for cleaning non-ferrous materials. The ash is sent through an air separation unit to remove paper, wood, plastic, and other unburned debris before passing the ash to an eddy current separator for non-ferrous material removal. The ash is free of metal values, unburned materials and unshreddables, but must be treated to immobilize certain heavy metals. The ash is recycled through a closed loop to increase removal efficiency of the metals and the homogeneous nature of the recovered treated ash aggregate. The apparatus used in this process is distinguishable for failing to require an inclined separator.
U.K. Patent Application No. GB 2,280,384 published on Jan. 2, 1995, for Patrick Brogan describes a horizontal bucket wheel sand washer with a submerged recovered fine aggregate transporter apparatus limiting its movement to prevent agitating the flowing water. The submerged transporter apparatus may be a screw conveyor or a multi-bladed scraper mounted on a frame reciprocated by rams and guided in an elevated return movement over pivoted cams. The apparatus is distinguishable for its required horizontal structure.
Japan Patent Application No. 8-168693A published on Jul. 2, 1996, for Kiyohiro Taniguchi describes an inclined apparatus to prevent fine aggregate such as sand from being mixed with the muddy water being carried off by a conveyor belt when the fine aggregate such as sand is taken out from a water tank by a belt conveyor device. The silt is collected in a hopper and passed to a conveyor belt while the muddy water is collected in a separate container. The apparatus is distinguishable for lacking any change in the inclination.
Japan Patent Application No. 9-203407A published on Aug. 5, 1997, for Yoshimichi Ishii et al. describes a screw conveyor and washer apparatus comprising multiple washers connected in a single line via microjoints. Multiple screws with individual washers in a single line are attached to a supplying means of unknown material. Each washer is separated in turn at its microjoint part so that the screw with its washer is supplied. The apparatus is distinguishable for its required microjointed structure.
German Patent Application No. DE 199 28 287 A1 published on Dec. 28, 2000, for Steffen Prieske describes a method for disposing excavated waste material by conveying the waste material to a buffer container for delivery to a drum washer, wherein coarse particles are separated from finer particles, and the overflow is supplied to a hydro-cyclone screen apparatus for recycle of the fluid and the disposal of the solids to a dump. The apparatus is distinguishable for requiring a drum washer and a hydro-cyclone screen.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus, a load sensing system solving the aforementioned problems is desired.


A stereoscopic retinal camera comprises an illuminating optical system, a photographing optical system, an observation optical system and a focus detection optical system. The focusing optical system consists of an index projecting system combined with one of the two light paths of the observation optical system, and an index detecting system combined with the other light path of the observation optical system. The respective positions of the focusing lenses of the photographing optical system are adjusted so that a sharp image of the focusing index is detected by the index detecting system. Thus, the stereoscopic retinal camera can be easily focused without requiring any particular skill and is capable of enabling the minute observation of the fundus of the eye by means of a direct-vision viewfinder.

1. Field of the Invention
The present invention relates to a stereoscopic retinal camera and, more particularly, to a focus detecting system to be incorporated into a stereoscopic retinal camera.
2. Description of the Prior Art
In focusing a conventional stereoscopic retinal camera on the spatial image of the retina, the spatial image is superposed on the reticule of a viewing system and the focusing condition of the spatial image is observed through the viewing system. Since the condition of the image in the viewfinder is directly dependent on the refracting power of the eyes of the observer, the refracting power of the viewfinder must be exactly adjusted and accurate focusing requires highly skillful focusing technique.
Referring to FIG. 10, a monocular retinal camera disclosed in Japanese Patent Publication (Kokoku) No. Sho 61-39050 comprises: a photographing optical system comprising an objective lens 51 to be disposed opposite to the eye E, a diaphragm 52 in a conjugate relation with the pupil EP of the eye E, a focusing lens 53, an image-forming lens 54 and a film 55 (the focusing lens 53 and the image-forming lens 54 constitute an afocal optical system); a viewfinder optical system comprising a reflecting mirror 72 disposed before the film 55, a field lens 73 disposed on a path along which a light beam reflected by the reflecting mirror 72 passes, a reflecting mirror 74 and an ocular 75; an illuminating optical system comprising a perforated reflecting mirror 56 disposed at a position before the diaphragm 52 on the light path of the photographing optical system, a relay lens 57 disposed on a path along which a light beam reflected by the perforated reflecting mirror 56 passes, a condenser lens 59, a circular slit plate 60, a flash lamp 61 for stroboscopic photography, a heat filter 62, a condenser lens 63 and an illuminating light source 64; and an index projecting system for facilitating focusing, comprising a reflecting mirror 65 disposed at a position after the diaphragm 52 on the light path of the photographing optical system, a reflecting mirror 66, a relay lens 67, a slit index 68, a deflecting prism 69 disposed contiguously with the slit index 68, a condenser lens 70 and a light source 71.
Light beam emitted by the illuminating light source 64 is reflected by the perforated mirror 56 and the reflected light beam passes through the objective lens 51 to illuminate the fundus ER. The light path of the index projecting system is branched from the light path of the photographing optical system by the reflecting mirror 65, i.e., a light path dividing means, disposed behind the perforated mirror 56. Thus, the focusing operation is not effected by illuminating condition, and the index projecting system and the photographing optical system are interlocked simply. Since the index illuminating light beam passes through the space between the illuminating light beam and the photographing light beam or overlap part of the illuminating light beam, the path of the index illuminating light beam needs delicate positional adjustment. The light path dividing means must be positioned so that the light path dividing means may not intercept the light beam of the focusing lens system.
A monocular retinal camera disclosed in Japanese Patent Publication (Kokoku) No. Sho 57-12294 is provided with a direct-vision viewfinder to observe the image of an index formed on the fundus by projecting a plurality of light beams cooperatively forming the image of the index for focusing, i.e., focus detection.
As shown in FIG. 11, the monocular retinal camera has a photographing optical system and an illuminating optical system comprising an objective lens 81, a photographing lens 82 serving also as a relay lens, a film 83, a diaphragm 84, a perforated mirror 85 for reflecting illuminating light, provided with a central hole, an illuminating light source 86, a condenser lens 87, a relay lens 88, and a ring slit 89. A light beam emitted by the illuminating light source 86 is converged on a focal point F1 by the condenser lens 87, gathered on the ring slit 89 by the relay lens 88, reflected by the perforated mirror 85 toward the objective lens 81 and focused on the pupil EP of the eye E by the objective lens 81 to illuminate the fundus EF. The image light reflected by the fundus EF passes through the refraction system of the eye E and the objective lens 81, is focused on the rear focal point F2 of the objective lens 81, passes through the hole of the mirror 85 and the diaphragm 84, and focused on the film 83 by the photographing lens 82 to form the image of the fundus EF on the film 83. The relay lens 88 of the illuminating optical system is equivalent to the photographing lens 82 of the photographing optical system. The relay lens 88 and the photographing lens 82 are equidistant from the perforated mirror 85. A half mirror 90 is disposed on the light path of the illuminating optical system before the relay lens 88, i.e., at a position on the side of the light source 86 with respect to the relay lens 88, so that the image of the index projected by an index projecting system is reflected toward the respective light paths of the illuminating optical system and the photographing optical system so that the image of an index is projected on the fundus EF. The index projecting system comprises a light source 91, a condenser lens 92, a slit index 93 disposed near a position where the condenser lens 92 gathers the light emitted by the light source 91, a split image prism 94 disposed near the slit index 93, a relay lens 95, and a two-hole diaphragm 96. The image of the slit index 93 is formed by the relay lens 95 on a plane FJ, which is in a conjugate relation with the film 83. The position of the two-hole diaphragm 96 corresponds to the position of the image of the ring slit 89 formed by the relay lens 88, the distance between the two holes is equal to the diameter of the image of the ring of the ring slit 89. A transparent glass plate 98 having a shading portion 97 of a size large enough to cover the image of the index formed on the fundus EF and capable of being removably inserted in the light path of the illuminating optical system is disposed at a position in a conjugate relation with the plane F3 to prevent the image of the index formed on the fundus EF being obscured by the illuminating light.
A method of focusing the index projecting system will be described hereinafter. The light image of the index 93 is split into two light images by the split image prism 94. Then, the two light images pass through the two holes of the two-hole diaphragm 96, the lenses 88 and 81, and reach the fundus EF to form the images of the index 93 on the fundus EF. The images formed on the fundus EF is observed through a viewfinder optical system comprising a viewfinder mirror 99 capable of being removably placed in the light path between the photographing lens 82 and the film 83, a reflecting mirror 100 and an ocular 101. Then, the photographing lens 82 and the relay lens 88 are shifted so that the film 83 and the plane F3 are in a conjugate relation with respect to the light reflected by the fundus EF, or the film 83, and the index projecting system including the plane F3 are moved to focus the photographing optical system. However, when this index projecting system is incorporated into a stereoscopic retinal camera, the two images of the index are further split if the convergence of the eyes of the observer is not appropriate, which makes focusing difficult, because two images are observed by the stereoscopic retinal camera. Although it may be possible to observe the fundus stereoscopically for minute inspection by the stereoscopic retinal camera provided with a direct-vision viewfinder, the image of the fundus and that of the index overlap each other and part of the fundus cannot be observed.


A high speed apparatus for cutting and wrapping soft chewing gum comprises a plurality of substantially parallel cutters having cutting heads to cut the gum into relatively thin rectangular-shaped pieces. The cutters are moved to a position where each individually shaped piece of gum is placed into a nest on a wrapping tray with a wrapper located therebetween. The cutters are moved in an eccentric ovoid path by a ring wheel and grooved cam wheel arrangement which causes the cutting heads to separate and move back together as they move through a cycle. During placement of the stick of gum in the nest, a flat side of the shaped piece of gum is urged against the flat bottom of the nest. The apparatus further comprises an apparatus to complete wrapping the wrapper around the piece of gum.

This invention relates generally to machines for wrapping articles. More particularly, this invention relates to a machine for cutting and wrapping soft or uncured gum. The present invention is particularly, but not exclusively, useful for high speed wrapping of sticks of soft or uncured gum which are rectangular shaped and relatively thin.

Soft chewing gum wrapping machine and method


A pool cleaner includes a housing having a front, rear and adjoining side portions and a base plate having a water inlet. A pump is configured to draw water and debris from the pool through the inlet for filtering and discharge filtered water through an outlet. A pair of wheels are coupled proximate the front and rear of the housing, each of which is coupled to an opposing end of an axle, each opposing end of the axle being slidably moveable along the housing in a forward and rearward directional path of the cleaner in response to a steering assembly. An on-board controller includes memory for storing a cleaning program, and a processor electrically coupled to the memory to execute the cleaning program to automatically control the steering assembly to position each end of the axles to steer the cleaner while it is moving in a forward or reverse direction.

Automated or robotic self-propelled swimming pool cleaners traditionally contact and move about on the pool surfaces being cleaned on axle-mounted wheels or on endless tracks that are powered by a separate drive motor through a gear train. The wheels or tracks are aligned with the longitudinal axis of the cleaner. Swimming pool cleaning robots that move on wheels generally have two electric motors, a pump motor that provides power to a water pump that is used to dislodge and/or vacuum debris up into a filter, and a drive motor which is used to propel the robot over the surfaces of the pool that are to be cleaned. The drive motor can be connected through a gear train directly to one or more wheels or axles, or through a belt and pulleys to propel the cleaner; or to a water pump, which can be external to the robotic cleaner that produces a pressurized stream, or water jet, that moves the cleaning apparatus by reactive force or by driving a water turbine connected via a gear train to the wheels or endless track. The movement of the pool cleaners of the prior art, when powered by either the turbine or the direct or reactive jet is in one direction and the movement is random.
Control of the longitudinal directional movement of the pool cleaner can be accomplished by elaborate electronic circuitry, as is the case when stepper and D.C. brushless motors are employed. Other control systems enable the cleaner to climb the vertical sidewall of the pool until a portion of the cleaner extends above the waterline and/or the unit has moved laterally along the sidewall, after which the motor drive reverses and the cleaner returns to the bottom surface of the pool along a different path. The water-powered cleaners of the prior art also rely on the reorientation of the cleaner while in contact with the wall to effect a random change in direction. However, under certain circumstances, it is a waste of time and energy, and produces unnecessary wear and tear to have the robotic cleaner climb the sidewall solely for purpose of changing the direction of movement of the cleaner.
It has also been proposed to direct the scanning movement of a pool cleaner mechanically by use of a three-wheeled array in which the third wheel is mounted centrally and opposite the other pair of wheels, and the axle upon which the third wheel is mounted is able to rotate in a horizontal plane around a vertical axis. A so-called free-wheeling version of this apparatus is shown on U.S. Pat. No. 3,979,788.
In U.S. Pat. No. 3,229,315, the third wheel is mounted in a plate and the plate is engaged by a gear mechanism that positively rotates the horizontal axle and determines the directional changes in the orientation of the third wheel.
It is also known in the prior art to provide a pool cleaner with a vertical plunger or piston that can be moved by a hydraulic force into contact with the bottom of the pool to cause the cleaner to pivot and change direction. The timing must be controlled by a pre-programmed integrated circuit ("IC") device.
It is also known from U.S. Pat. No. 4,348,192 to equip the feed water hose of a circular floating pool cleaning device with a continuous discharge water jet nozzle that randomly reorients itself to a reversing direction when the forward movement of the floating cleaner is impeded. In addition to the movable water jet discharge nozzle attached to the underside of the floating cleaner, the hose is equipped with a plurality of rearwardly-facing jet nozzles that move the water hose in a random pattern and facilitate movement of the cleaner.
Commercial pool cleaners of the prior art that employ pressurized water to effect random movement have also been equipped with so-called "back-up" valves that periodically interrupt and divert the flow of water to the cleaner and discharge it through a valve that has jets facing upstream, thereby creating a reactive force to move the hose and, perhaps, the attached cleaner in a generally backward direction. The back-up valve can be actuated by the flow of water through a fitting attached to the hose. The movement resulting from the activation of the back-up valve jets is also random and may have no effect on reorienting a cleaner that has become immobilized, e.g., in the corner of the pool or by a ladder or other obstruction.
The apparatus of the prior art for use in propelling and directing the scanning movement of automated robotic pool cleaners is lacking in several important aspects. For example, the present state-of-the-art machines employ pre-programmed, integrated circuit ("IC") devices that produce a specific predetermined scanning pattern. The design and production of these IC devices is relatively expensive and the scanning patterns produced have been found to be ineffective in pools having irregular configurations and/or obstructions built into their bottoms or sidewalls.
Cleaners propelled by a water jet discharge move only in a generally forward direction, and their movement is random, such randomness being accentuated by equipping the unit with a flexible hose or tail that whips about erratically to alter the direction of the cleaner.
Cleaners equipped with gear trains for driving wheels or endless tracks represent an additional expense in the design, manufacture and assembly of numerous small, precision-fit parts; the owner or operator of the apparatus will also incur the time and expense of maintaining and securing replacement parts due to wear and tear during the life of the machine. A cleaning apparatus constructed with a pivotable third wheel that operates in a random fashion or in accordance with a program has the same drawbacks associated with the production, assembly and maintenance of numerous small moving parts.
The robotic pool cleaners of the prior art are also lacking in mechanical control means for the on-site adjustment of the scanning patterns of the apparatus with respect to the specific configuration of the pool being cleaned.
In U.S. Pat. No. 6,742,613, a self-propelled robotic pool cleaner includes a reversible drive means for propelling the apparatus in opposite directions, which directions correspond generally to the longitudinal axis of the apparatus, and a pair of wheels assembled to each of the opposite longitudinal ends of the cleaner. Each pair of wheels are mounted to transverse axles, which are manually positioned and secured at an angle that is acute to the longitudinal axis of the apparatus when the cleaner is moving in at least one direction. In an embodiment, the axles are mounted in slots formed in the base of the housing, and one or more manually adjustable pins are provided to fix and/or change the range of movement of the axle in the slot. These adjustments allow the operator to customize the pattern based upon the size and/or configuration of the specific pool being cleaned. In this manner, the cleaner moves in a clockwise or counter-clockwise direction until the operator manually adjusts the pin positioning to thereby change the angle of the axle with respect to the longitudinal axle.
European Patent No. EP 1,472,425 discloses a swimming pool cleaner that includes wheels fixedly connected to an axle which is transversely mounted through elongated slots formed in the sidewalls of the cleaner proximate each wheel. The axle is mounted on a central pivot that allows the axle to move forward and backward within the physical constraints of the opposing ends of the elongated slots. A rotating fork having two projections, one on either side of the axle must be manually set to provide different steering paths for the cleaner.
A significant deficiency in the design and operation of the pool cleaners of the prior art is their tendency to become immobilized, e.g., in sharp corners, on steps, or even in the skimmer intake openings at the surface of the pool. In such circumstances, the pool cleaner has limited mobility at best, or is incapable of traversing and cleaning the surface of the pool in a worst case scenario.
Yet another significant deficiency in the design and operation of pool cleaners of the prior art is the entanglement or twisting of the buoyant power cable that provides power from an external power source to the cleaner. In particular, as the cleaner turns during cleaning operations, the floating portion of the power cable can become twisted as it helically winds in a counter-clockwise or clockwise direction. The undesirable twisting or coiling of the power cable shortens the length of the power cable, exerts forces on the cleaner that can oppose the movement of the cleaner, as well as places undesirable stresses on the electrical contacts between the power cable and the cleaner.
Swivel connections have been mounted on the top of the cleaner in an attempt to reduce the coiling of the power cable as the cleaner turns. Unfortunately, the swivel mounts do not always prevent the undesirable coiling of the power cable during the continuous turning of the cleaner.

Axle controller for automated swimming pool cleaners


A bucket for an excavator or loader including a base wall having a side with a substantial or partly concave shape, the side with the substantial or partly concave shape has a front section that is raised, flat or concave and a rear section that has a concave arc. The base wall side has a discontinuous curve from the front section to the rear section. The bucket has two side walls spaced apart by the base wall. The bucket has mounting mechanism for mounting the bucket to the excavator or loader. The raised, flat or concave front section assists in retaining excavated material within the bucket.

Excavator buckets are used by excavators and like vehicles to dig the earth and remove dirt. Conventional excavator buckets have a concave base wall separating two side walls that together form a bucket shape. Many of the excavator buckets have a series of teeth on the leading edge to penetrate the ground.
Because of the impact forces associated with penetrating and digging the ground, the excavator buckets have walls of thickened metal plates to withstand these forces. The hydraulic-operated arms of the excavators can lift loaded buckets up to a maximum threshold weight. As the buckets are relatively heavy because they are made of the thick metal plates, there is a limit to the amount of dirt it can carry before the maximum threshold weight limit is reached.
Furthermore, conventional buckets have a concave shape to hold and retain the collected dirt. However, collecting dirt with a concave shaped bucket has problems in that collected dirt flowing into the bucket sometimes falls out of the concave shaped bucket. There is a maximum volume of dirt collected and retained by the bucket because of the shape of the bucket.


The invention refers to an elevator door leaf comprising a door panel and a support structure having at least one profile. The door leaf comprises a vertically extending expansion member which is fixed to the door leaf only at one vertical level, whereby the expansion member consists of a material having a larger thermal expansion coefficient than the material of the door panel and/or of said profile.

The present invention relates to an elevator door leaf which is used for car and/or landing doors in an elevator. The door leaf comprises at least one door panel and a support structure, e.g. a frame, with at least one profile, which advantageously extends vertically in the area of the leading side edge during the closing movement of the door leaf.


Methods are provided for separating linear nucleic acid fragments based on their conformation. The methods are based on novel two-dimensional gel electrophoresis techniques. In one aspect the method comprises electrophoresing a sample of nucleic acids in a first dimension said sample through a gel matrix under a first set of pre-determined electrophoresis conditions; electrophoresing said gel matrix in a second dimension under a second set of electrophoresis conditions, such that linear nucleic acid fragments of equal length but having different conformation are separated; said first and second electrophoresis conditions are different, such that in one of said dimensions electrophoresis allows separation of linear nucleic acid fragments based on conformation and length, and in the other of said dimensions electrophoresis allows separation of the sample fragments based substantially on length. Said difference is preferably established with a chemical agent capable of reducing conformational differences between linear nucleic acids fragments.

Unusual secondary structures in linear DNA fragments often lead to significant conformational changes of the entire molecule. Such conformational changes of linear nucleic acids fragments frequently result in curvature, characterized by decreased end-to-end distance. Curvature has for example been detected or proposed in linear DNA fragments containing mispaired bases, insertion/deletion loops, UV-lesions, base adducts, base methylation, A-tracts, GGCC sequences, cross-links, DNA hairpins or cruciforms, slipped-strand structures, protein binding and nicking. DNA conformation in general, and conformational changes of linear DNA fragments because of altered secondary structure, have been analyzed using various direct and indirect methods such as X-ray diffraction, nucleic magnetic resonance spectroscopy (NMR), electron microscopy (EM), fluorescence resonance energy transfer (FRET), and gel retardation analysis.
Some gel electrophoresis methods allow separation of linear DNA fragments based on both length and conformation, while others separate DNA fragments based essentially on their length. Polyacrylamide gel electrophoresis (PAGE) is an example of a method in the former category and agarose electrophoresis an example of the latter. A rigorous physical theory of gel electrophoresis through a matrix capable of separating DNA fragments based on length, or both length and conformation, has not been presented. However, it has been recognized that PAGE allows conformation-dependent separation of linear DNA fragments in such way that migration decreases as the square of the degree of curvature for each linear DNA fragment separated [1]. This quantitative relationship between curvature and migration of linear DNA fragments has been used experimentally to evaluate DNA curving. Such methods are based on the fact that linear DNA fragments with altered conformation migrate at a different rate through a gel matrix compared to DNA fragments with normal conformation. These differences in migration rates can further be used to separate and isolate linear DNA fragments based on their conformation if the length of each fragment is known. In principle, it should be possible to separate linear DNA fragments of equal length with various conformations using PAGE with sufficient resolution.
A few previously described analytical methods used to screen for mutations or polymorphism are based on this principle. Heteroduplex analysis (HA) is a method used to scan for polymorphism by comparing migration rates of mismatched heterohybrids and perfectly matched hetero- and homohybrids. After melting and reannealing of homologous DNA samples from two or more individuals, the DNA mixture will contain both heterohybrids, some or all are mismatched if there is polymorphism between individuals, and perfectly matched homohybrids. Alternatively, the mixture will contain perfectly matched hetero- and homohybrids if the DNA samples are identical in sequence. After reannealing, the DNA mixture is analyzed using PAGE. If the sample contains mismatched heterohybrids, their migration will be retarded through the gel due to their altered conformation compared to the perfectly matched duplexes. Several variations to increase the sensitivity and reliability of HA have been developed. Conformation Sensitive Gel Electrophoresis (CSGE) is a well-known variation of HA [2, 3]. This system uses mildly denaturing solvents to enhance the tendency of single-base mismatches to produce conformational changes (see U.S. Pat. No. 5,874,212 to Prockop, et al.).
Use of previously described methods for conformation-dependent separation of linear DNA fragments, such as HA and CSGE, are limited to situations were the analyzed DNA molecules are of known length. In addition, only simple DNA samples containing one or at most a few different DNA fragments can be tested. If the sample contains a complex mixture of DNA fragments of different lengths it would be impossible to identify which of them show difference in migration because of their conformation since individual bands would overlap or not resolve sufficiently. This is a major drawback since it limits application of this technology. Similar limitations would also apply to other comparable techniques based on capillary electrophoresis or chromatography (e.g. dHPLC).
Methods for separating individual linear DNA fragments from a complex mixture based only on their difference in conformation, independent of their length, would be of great interest. Such methods would allow analysis of complex samples containing many linear DNA fragments of different length. Examples where such methods could be used include but are not limited to: Physical separation of mismatched heterohybrids and perfectly matched hetero- and homohybrids allowing isolation and enrichment of either class; simultaneous mismatch scanning of multiple fragments; isolation of damaged DNA molecules from bulk amount of undamaged molecules, and estimation of the efficiency of nucleic acid reannealing.
One possible way to achieve length independent, or essentially length independent, separation of linear DNA fragments based on their conformation is to develop two-dimensional (2-D) gel electrophoresis systems. Such a system would separate DNA fragments based on both length and conformation in one dimension but only on length in the other dimension.
Two different 2-D gel electrophoresis methods capable of separating linear DNA fragments based on conformation were described in the late eighties [4, 5]. These two methods use different approaches to resolve linear DNA fragments with certain conformations. Both of these methods provided separation of curved linear DNA fragments containing adenine-tracts (A-tracts). One of these methods combines agarose and PAGE electrophoresis using the different migration behavior of curved linear DNA fragments in these two matrixes. The other method uses temperature-dependency of DNA structure and conformation. By using different temperature for each dimension (10° C. and 60° C.) different conformations are induced resulting in differences in migration rates. DNA curvature due to A-tracts results from different stacking interactions between adjacent adenine bases in the molecule. A-tract curvature is not very rigid and can therefore be removed or reduced by increasing the temperature of the system [6, 7]. It is not disclosed or suggested in the prior art, that these or other systems can separate other more rigid conformations, such as those formed in mismatched or UV damaged duplexes. In our experience, it is not possible to separate mismatched duplexes from perfectly matched duplexes using temperature as a variable between the two dimensions. This is perhaps due to secondary and tertiary structures resulting from mismatches are less temperature dependent than in the case of A-tracts. The combined agarose-PAGE system is limited by difficulties in transferring linear DNA fragments between the two different matrixes in an efficient and reproducible manner.
A 2-D gel electrophoresis system using neutral-neutral agarose gel electrophoresis for the separation of relaxed circular DNA and supercoiled DNA from linear DNA using ethidum bromide in the second dimension is disclosed in WO 97/39149. In the first dimension, DNA molecules are separated in proportion to their mass using low voltage in low percentage agarose. The second dimension is run at high voltage in a gel of higher agarose concentration in the presence of the intercalator ethidium bromide. Under these conditions, mobility of all circular DNA molecules is drastically influenced by their shape but mobility of linear DNA fragments are essentially the same as in the first dimension. After separation and nucleic acid staining a pattern is detected. The pattern consist of generally three arcs lying in front of the forth arc which contains linear or linearized DNA. Arc 1 contains opened circles (relaxed) DNA. Arc 2 contains covalently closed circles that were converted to a relaxed form. Arc 3 contains covalently-closed (supercoiled) DNA. It should be emphasized that this method cannot be used to separate linear DNA fragments according to conformation because of the fact that linear DNA fragment of same length with different conformation are separated almost entirely according their size in agarose gel electrophoresis. Further, perhaps due to these limitations, the reference does not disclose or suggest 2-D gel electrophoresis methods for separating other types of conformational different DNA molecules, such as curved linear DNA fragments containing unusual secondary structure, e.g. mismatched duplexes.
Two types of 2-D gel electrophoresis system have been described for mapping origins of replication [8, 9]. One of the systems uses neutral-neutral agarose gel electrophoresis as described above. The other system uses neutral-alkaline agarose gel electrophoresis to achieve separation according to size and structure in the first dimension and only size in the second dimension. These systems allow separation of large non-circular DNA molecules with unusual structure such as those formed in replicons (large DNA bubbles and Y shaped DNA replication forks). Linear DNA fragments that are curved due to existence of local unusual secondary structure such as UV-lesion or insertion bulges cannot be separated in these systems. The difference in conformation of such linear DNA fragment with or without unusual local secondary structures is not great enough to ensure different migration in agarose elctrophoresis and will therefore not be detected in this system.
An ideal 2-D gel electrophoresis system for conformation-dependent separation of linear nucleic acids fragments would preferably be based on a single gel matrix eliminating the troublesome transfer step between two different gel matrixes. Such transfer often gives rise to trailing effects, which lower the detection capability of the system. A physical or chemical factor would then be introduced (or removed) after the first dimension to affect the conformation of different linear DNA fragments to a different degree depending on secondary and tertiary structure. Such physical or chemical factor should allow the differentiation of minor as well as major conformational differences, such as e.g. caused by single base pair mismatched DNA and insertion or deletion bulges.
Many chemical factors have been reported to affect conformation of linear DNA molecules, e.g. mono- and divalent cations such as Na+ and Mg2+. DNA curvature generally increases with increasing concentration of cations. Chemical factors that decrease curvature of DNA fragments containing unusual secondary structures would generally be of more interest than those that increase DNA curvature. Intercalators are small planar molecules, which form hydrophobic interactions with nucleic acids by insertion (intercalation) between DNA base pairs. Such interactions require untwisting of the DNA molecule to enable enough space between adjacent base pairs for the intercalator molecule. This separation of base pairs and concurrent untwisting results in increased length and stiffness of the DNA molecule thus affecting its whole conformation [10]. It has been reported that addition of intercalators to linear DNA fragments, curved because of A-tract, can greatly reduce the curvature [11-14]. This has been determined both with PAGE electrophoresis and electron microscopy studies. We have now defined conditions were some intercalators also greatly reduce the curvature of linear DNA fragments containing insertion/deletion loops or UV adducts as determined by gel retardation analysis in PAGE electrophoresis.
It is a well-known fact that linear single-stranded DNA fragments migrate essentially only according to length in PAGE containing highly concentrated denaturating chemical agents. Such behavior of single-stranded DNA is the basis of common techniques in DNA sequencing. We have found that after separation of mismatched DNA molecules both according to length and conformation it is possible to denaturate DNA molecules in the gel with addition of denaturating chemical agents and heating for given amount of time. Thus, it is possible to separate single stranded DNA fragments in the second dimension only according to length allowing formation of electrophoresis system capable of conformation dependent separation.

Method for two-dimensional conformation-dependent separation of non-circular nucleic acids


An optical member supporting device is described that includes, in an XYZ rectangular coordinate system, spherical bodies, a first holding portion and a second holding portion, an optical member held by the first holding portion or the second holding portion, first yokes protruding from the first holding portion facing the second holding portion, and second yokes protruding from the second holding portion facing the first holding portion and opposed to the first yokes in a predetermined direction in the X-Y direction. The first holding portion and second holding portion extend in an X-Y direction and are opposed in a Z direction with the spherical body interposed therebetween. The second holding portion includes a second magnet and the first yokes and the second yokes are opposed to the second magnet in the Z direction.

The camera devices mounted on electronic apparatus such as smartphones and the like include those having optical hand shake correction function. There is a patent document of Korea patent laid-open No. 10-2016-0021158 (hereinafter referred to as "Patent Document 1" disclosing a technique related to this type of camera device. The camera module of PATENT DOCUMENT 1 has a configuration including: a first hand shake correction part, wherein a first frame, a second frame, and a third frame with a lens-barrel are accommodated in a nested structure, and the second frame and the third frame are moved within the first frame along a first direction perpendicular to the optical axis; and a second hand shake correction part, wherein the third frame is moved within the first frame along a second direction perpendicular to the optical axis and the first direction.
However, in the case of the technology in PATENT DOCUMENT 1, a three-layer structure has to be used. In this three-layer structure, straight-advancing mechanism toward the first direction, guide intermediary body, and straight-advancing mechanism toward the second direction are laminated in the Z direction, and each of the layers is connected by a guiding structure using spherical bodies. Thus, a problem that the bulkiness in the Z direction becomes larger is resulted.
The present disclosure has been made in view of such problem, and an object thereof is to provide an optical member supporting device, an optical member driving device, a camera device, and an electronic apparatus that enables movement in the XY plane and rotation around the Z axis with small friction and that can be mounted on a thin electronic device such as a smartphone.

Optical member supporting device, optical member driving device, camera device and electronic apparatus


When the inner surface of containers conveyed in an inverted posture is sterilized, the sterilization efficiency can be increased, the amount of sterilizing fluid used can be reduced, the sterilization time and washing time can be shortened, the number of drive components of the apparatus can be reduced and the apparatus can be simplified and reduced in cost. A non-inserted nozzle 20 is disposed at a distance of 1-50 mm below the lower end surface 52 of a mouth of a container conveyed in an inverted posture, the sterilizing fluid is mixed with air and the sterilizing fluid is atomized and sprayed intermittently from the non-inserted nozzle toward the inside of the container.

A method in which containers are sterilized in an inverted posture by using an aqueous solution of peracetic acid has been widely used for sterilizing bottles in an aseptic filling system. This sterilization method generally employs a procedure in which a bottle is held in an inverted posture, a spraying nozzle is inserted into the bottle mouth, and a sterilizing fluid is sprayed at least as a straight stick-like flow on the inner surface of the bottle, but the sterilization effect of the inside of the container in this method depends on whether the sprayed sterilizing agent or washing water directly collides with the inner surface of the container or the inner surface of the container is wetted when the liquid flows down along the inner surface of the container after the collision with the surface. The resultant problem is that if the flow rate is decreased, then uniform wetting characteristic of the inner surface of the bottle is deteriorated and sterilization is incomplete. For this reason, a large quantity of sterilizing fluid has to be sprayed inside the container within the predetermined time. Furthermore, in the case of synthetic resin containers such as PET bottles, complex concave-convex shape, such as reinforcing ribs, are present on the bottom and body section to increase the rigidity of container. Therefore, a large quantity of sterilizing fluid has to be sprayed over a long period in order to wet uniformly the entire inner surface of the container, thereby hindering the transition to speedup of lines that has been urgently required in recent years. Furthermore, that a large quantity of sterilizing fluid is required causes waste of the sterilizing fluid and high cost. Moreover, in the washing process, the sterilizing fluid (sterilizing liquid) that has adhered to the inner surface of the container in the sterilization process has to be completely washed off. Accordingly, the washing water has to come into contact with the entire inner surface of the container, in the same manner as in the sterilizing process in order to wash off the sterilizing liquid, and there are the problems that are similar to that in the sterilizing process.
In order to solve the above-described problems, the inventors have suggested a method by which the contact ratio of a sterilizing fluid with the inner surface of a bottle is increased and sterilization is conducted with high efficiency in which a first spraying hole is formed in the center of a distal end section of a spraying nozzle that is to be inserted into the mouth of the inverted bottle and a second spraying hole is formed to be circumferentially opened below the first spraying hole, the liquid sprayed from the two spraying holes toward the bottom section of the container flows down, and part of the liquid is stirred and pushed up by the sterilizing fluid sprayed from the second spraying hole and scattered over the inner surface of the bottle (ref. Patent Document 1).
A method for washing and sterilizing containers according to which a nozzle having a section to collect liquid is disposed below a container mouth, a mist or liquid flow supplied from a spraying hole of the nozzle is brought into contact with a reflux flow, and the distal end of the mist or liquid flow that collides with the inner surface of the container is constantly oscillated over the inner surface of the bottom section of the container has also been suggested as a method for sterilizing or washing a container in which the container is held in an inverted posture and a nozzle is not inserted into the container (ref. Patent Document 2).
Patent Document 1:
                Japanese Patent Application Laid-open No. 2003-181404Patent Document 2:        Japanese Patent Application Laid-open No. 6-121974

Method for container sterilizing and washing and apparatus therefor


Various embodiments of methods and apparatus for load balancing requests such that target resources serve a single client are described. In at least some embodiments, a single resource, such as a compute instance, is assigned to only one client, and that single resource is used for all subsequent connections and communications from that client. Some embodiments comprise a resource selection system which provides identifying information of an available resource, in order for a connection to be established between the client and the resource. The resource selection system then removes that identifying information from its memory. In some of these embodiments, a routing layer interfaces with the resource selection system to establish the connection between the client and the available resource. When a client is assigned to a resource, other clients may be prevented from establishing connections with the resource.

As the scale and scope of network-based applications and network-based services such as cloud computing services have increased, data centers may house hundreds or even thousands of host devices (e.g., web servers) that need to be load balanced. Conventional load balancers may include multiple network interface controllers (NICs), for example eight NICs, with some of the NICs handling inbound traffic from/outbound traffic to clients and the other NICs handling outbound traffic from/inbound traffic to the host devices (e.g., servers such as web servers) that are being load balanced. Load balancers typically also include logic that implements load balancing techniques such as round robin and/or least connections techniques to select which host device will handle a connection from a client.
In conventional load balancers, clients communicate with selected host devices on connection(s) that pass through the load balancer, and thus the data exchanged between a client and a selected host device in a conventional load balanced system flows through the load balancer. Some conventional load balancers may serve as proxies to the host devices that they front, and thus may terminate connections (e.g., Transmission Control Protocol (TCP) connections) from the clients and send the client traffic to the host devices on connections (e.g., TCP connections) established between the host devices and the load balancer. In other conventional load balancers, the load balancer does not terminate connections from the client and the host device. Instead, connections (e.g., Transmission Control Protocol (TCP) connections) are established between clients and host devices that pass through the load balancer. The load balancer modifies header information (e.g., TCP and IP header information) in packets that pass through the load balancer on the connections to transparently route traffic between the clients and host devices. These load balancers may be viewed as serving as routing/network address translation (NAT) firewalls between the clients and the load balanced host devices.

Load balancing requests such that target resources serve a single client


A vehicle pillar structure includes a reinforcement that is provided in a vehicle pillar and that includes a buckling portion and a strain reducing face portion, wherein the buckling portion serves as a starting point of buckling; and the strain reducing face portion is adjacent to the buckling portion in a lateral direction of the reinforcement and reduces strain that occurs when the buckling.

1. Field of the Invention
The invention relates to a vehicle pillar structure that includes a buckling portion.
2. Description of the Related Art
A known technology in this technical field is described in Japanese Patent Application Publication No. 2005-7949 (JP-A-2005-7949). A center pillar described in Japanese Patent Application Publication No. 2005-7949 (JP-A-2005-7949) is provided with a reinforcement made of metal, and the reinforcement is provided with a recessed buckling portion that serves as a starting point of buckling. Therefore, when external force acts on the center pillar, the center pillar starts buckling at the buckling portion, and the metal reinforcement undergoes an extending deformation, whereby energy of the external force may be absorbed.
However, in the conventional pillar structure described above, although the reinforcement is provided with the buckling portion in order to control the buckling deformation of the pillar, the strain that occurs at the buckling portion of the reinforcement is large, so that an ideal deformation mode of the pillar cannot be obtained.
In addition, because the strain that occurs at the buckling portion is large, it may be difficult to control the deformation mode of the pillar, such as when the reinforcement is formed from a high-tensile steel with low extensibility.


A semiconductor manufacturing apparatus includes a loadlock module including a loadlock chamber in which a substrate container is received, wherein the loadlock module is configured to switch an internal pressure of the loadlock chamber between atmospheric pressure and a vacuum; and a transfer module configured to transfer a substrate between the substrate container received in the loadlock chamber and a process module for performing a semiconductor manufacturing process on the substrate, wherein the loadlock module includes a purge gas supply unit configured to supply a purge gas into the substrate container through a gas supply line connected to the substrate container; and an exhaust unit configured to discharge a gas in the substrate container through an exhaust line connected to the substrate container.

The inventive concept relates to a loadlock module and a semiconductor manufacturing apparatus including the same.
As semiconductor devices have recently been highly integrated and circuits have recently been miniaturized, in order to prevent the yield of semiconductor products from being reduced due to contamination of wafers due to exposure to external environments during semiconductor manufacturing processes, there is demand for semiconductor manufacturing equipment to maintain a high level of cleanliness. In order to meet the demand, in general, semiconductor manufacturing equipment includes a load port on which a wafer carrier called a front opening unified pod (FOUP) is placed, an equipment front end module (EFEM) maintained at a high level of cleanliness, a loadlock module configured to temporarily receive a wafer and having an internal pressure adjusted between atmospheric pressure and a vacuum, a transfer module configured to transfer the wafer, and a process module configured to perform a semiconductor manufacturing process on the wafer.

Loadlock module and semiconductor manufacturing apparatus including the same


A device for generating clock signals for use with a plurality of DDR memory devices on a dual in-line memory module (DIMM) board is provided that has a data buffer for buffering data. A clock divider divides a first clock signal (CLK1) having a first clock frequency to generate a second clock signal (CLK20) having a second clock frequency which is an integer multiple of the first clock frequency. A shift register (SH) receives the second clock signal as a data input signal, and comprises a plurality flip-flops having clock inputs coupled to receive the first clock signal (CLK1), and further coupled so that the data output of a preceding flip-flop is coupled to be the data input of a following flip-flop. The second clock signal is shifted through the shift register (SH) in response to the first clock signal (CLK1) to generate a plurality of shifted clock signals (CLK 21, . . . , CLK32) at respective data outputs of the plurality of flip-flops. A multiplexer commonly coupled to the data outputs of the flip-flops selects one of the shifted clock signals (CLK 21, . . . , CLK32) to serve as an output clock signal for transmission of the buffered data to a memory device.

On a typical buffered dual in-line memory module (DIMM) board, a number of memory modules and a memory buffer are arranged. The memory buffer constitutes the interface between the memory controller and the memory modules spread over the board. The memory modules (as, for example, Dynamic Random Access Memories or DRAMs) require a specific and precise timing at their data, address and clock inputs. As the memory boards (DIMM boards) have a dense routing in terms of numerous wires, providing suitable and exact timing of the data and address signals, as well as the corresponding clock signals, places a high requirement on the memory buffers. If the memory buffers fail to meet the requirements, the timing at the inputs to the memory devices may be different from the timing at the corresponding outputs of the controlling devices, which may impair the overall performance of the memory systems. In order to satisfy the different timing requirements, conventional solutions shift the phase of the clock signals. For this purpose, phase locked loops (PLL) with phase mixers or delay locked loops (DLL) are used to optimize the phase relationship of a clock signal with regard to a data signal. However, PLLs and DLLs consume a considerable amount of chip area. Further, as data throughput of the memory buffering devices increases, the power consumption and the heat produced in the memory buffering devices, in particular in the DLLs and PLLs, creates problems.

Integrated circuit for clock generation for memory devices


A method and a corresponding system for assessing a haemodynamic parameter for a vascular region of interest of a patient based on angiographic images are provided. After acquiring multiple angiographic images, a three dimensional (3D) representation of at least a first portion of the respective region of interest is performed, and geometric features are extracted from complete or partial views. Additional geometric features are extracted from partial incomplete views. A complete set of 3D geometric features for an anatomical structure, such as a vessel tree, is then generated by combining the extracted geometric features and estimating any missing geometric features. Using the complete set of 3D geometric features, a feature-based assessment of the haemodynamic parameter, such as a fractional flow reserve, is then performed.

The present embodiments relate to assessing a haemodynamic parameter.
Today, angiography is a well-established medical imaging technique. Coronary angiography, for example, is considered the gold standard for anatomical assessment of coronary artery disease. Nonetheless, coronary angiography has some intrinsic limitations and shortcomings. One of the most significant limitations of coronary angiography is an inability to accurately assess the physiological significance of lesions. Subject-specific physiology modeling may address this limitation. The approach includes determining the geometry features of the patient-specific arterial tree, and subsequent use of a computational model designed to predict functional diagnostic indices, such as FFR, as a function of the geometry.
US 2014/0058715A1 discloses a method and a system for non-invasive functional assessment of a coronary artery stenosis. Therein, patient-specific anatomical measurements of coronary arteries are extracted from medical image data acquired during a rest state of the patient. Based thereon, patient-specific rest state boundary conditions of a model of coronary circulation are calculated. Additionally, patient-specific hyperemic boundary conditions of the model are calculated based on the rest boundary conditions and a model for simulated hyperaemia. A hyperemic blood flow and pressure across a stenosis region are then simulated using the model of coronary circulation and the hyperemic boundary conditions to, finally, calculate a fractional flow reserve of the stenosis region.
US 2017/0032097A1 discloses a method and a system for enhancing medical image-based blood flow computations using invasively acquired physiological measurements. A patient-specific anatomical model of the patient's vessels is generated from non-invasively acquired medical image data. A computational blood flow model is then personalized using the invasive physiological measurements. One or more haemodynamic quantities of interest are then computed using this personalized computational blood flow model.
In standard coronary angiography, a limited number of 2D projections of vessels or vessel segments of interest are acquired, for example, through x-ray imaging. A combination of a pair of 2D images or views of the same vessel taken from different angles or angulations generally allows or enables a representation of the vessel in 3D space. The representation in 3D space may include or consist of a 3D anatomically accurate geometrical model, to which the following description may generically refer as a 3D reconstruction. Nonetheless, a 3D representation of, for example, a vascular tree may include or consist of, for example, a tree of branching centerlines of vessels or vessel segments, with each centerline point being associated to a radius or diameter value representing a local size of the respective vessel or vessel segment. Equivalently, within the scope of the present embodiments, the vascular tree of interest may be represented by a collection of features of a 3D geometry, such as a number of branches, a length of each branch, an average caliber of the branch, a shape of a cross-section of each branch, etc.
Since coronary angiography is typically concerned with and therefore focused on very specific parts or features, such as a stenosis, a respective field of view in each 2D image or 2D projection is optimized for visualization of this exact part or feature of the diseased vessel. In many cases, this limits the possibility of reconstructing or characterizing neighboring vessels to obtain a complete representation or reconstruction or model of the vessel tree surrounding an imaged feature of interest, such as a stenosis. In typical sets of angiographic images, the neighboring, presumably healthy, vessels may not be clearly visible, for example, due to a complex geometry of the vessel tree and/or foreshortening or overlaps with other anatomical structures. In these cases or conditions, it is not possible to fully represent or reconstruct the complete 3D geometry and topology of the vessel tree or arterial tree.
In some cases, additional images, such as previously acquired anatomical scans of the same patient, may provide additional data to enable the 3D representation of the complete vessel tree. If there is sufficient overlap between the angiographic images and the additional images or data, a single comprehensive 3D representation may be achieved by combining all available data. The required additional data is, however, not reliably available for every patient. Therefore, to fully represent or reconstruct the vessel tree in a region of interest, additional images would have to be acquired at the cost of additional exposure of the patient to radiation and contrast medium as well as additional expenditure of time and money.
Even if additional images are available or acquired, it may be impossible or extremely difficult to combine all data into a single complete and correct 3D representation. One difficulty lies in the needed registration between different datasets, which, for example, may have been acquired at different points in time and/or using different imaging equipment. If, for example, the patient has been moved or repositioned between the respective acquisitions of the different datasets, corresponding representations may be obtained in different coordinate systems. In this case, combining the respective data or models into a single cohesive and consistent 3D model may, at least for practical purposes, be impossible without proper position tracking at all times.

Method and system for assessing a haemodynamic parameter


A liquid crystal display device includes a pair of substrates facing each, first and second electrodes formed on each inner surface of the substrates and arranged so that they are crossed and face each other, first and second aligning films covering each inner surface of the substrates and said first and second electrodes and provided with an aligning treatment in a direction respectively, and a liquid crystal member sealed between the substrates by a seal layer. The liquid crystal layer is twistingly aligned by the aligning force of said first and second aligning films at an angle of approx. 230.degree. to 250.degree., and has a positive dielectric anisotropy. The liquid crystal layer includes a liquid crystal member having a dielectric constant ratio .DELTA..epsilon./.epsilon..perp. defined as a ratio of the dielectric anisotropy .DELTA..epsilon. and the dielectric constant .epsilon..perp. with the direction orthogonal to the liquid crystal molecule axis of 2 or less, and a elastic constant ratio K.sub.33 /K.sub.11 defined as a ratio of a bent elastic constant K.sub.33 to a splay elastic constant K.sub.11 of 1.75 or more.

1. Field of the Invention
The present invention relates to a field-effect-type liquid crystal display device to be time-division driven (multiplex-driven).
2. Description of the Related Art
A liquid crystal display device is widely used as a display device of office equipment. A liquid crystal display device with a large number of pixels and high display quality is requested according to enlargement of the display screen size. A liquid crystal display element consisting of a single matrix structure allowing the element structure and drive unit to be simplified is widely used for the office equipment.
The liquid crystal display element consisting of the single matrix structure has one substrate in which a signal electrode is formed like a stripe, another substrate in which a scanning electrode is formed like a stripe so that the signal and scanning electrodes cross each other, and a liquid crystal cell consisting of a twisted liquid crystal member sandwiched between both substrates. A pair of polarizing plates is installed outside the liquid crystal cell. The pixel formed on the portion where the scanning and signal electrodes are crossed is turned on/off by supplying a scanning signal to the scanning electrode and a data signal to the signal electrode synchronously with the scanning signal.
For the time-sharing driving method, a stroke is produced between turned-on and turned-off pixels. Therefore, if the number of time divisions for time-division driving is increased, the difference of the voltage applied to the turned-on and turned-off pixels or the operating margin decreases, the contrast is impaired, and the view angle narrows. The conventional TN-type liquid crystal display element only takes the number time divisions of up to the duty ratio of approx. 1/60 because it is inferior in the sharpness of brightness change for the applied voltage. Therefore, it is difficult to obtain a display device with a high quality and large size.
To improve the sharpness, STN-type and SBE-type liquid crystal display elements with a large twist angle are practically used. These liquid crystal display elements can take the number of divisions of up to the duty ratio of approx. 1/200 when the sharpness is improved by increasing the twist angle to 180.degree. to 270.degree..
Therefore a liquid crystal display element with 640.times.400 dots uses the method in which a display screen is divided into upper and lower groups and each group is driven by the duty ratio of 1/200. The liquid crystal display element with upper and lower groups divides the signal electrode into upper and lower portions at its center. Therefore, the area of the pixel adjacent to the boundary between two divided portions changes depending on the substrate alignment accuracy and the line to divide the screen appears. In addition, because the signal electrode is divided into upper and lower portions, the number of driving circuits for supplying the data signal to the signal electrode requires two times as many as the number of signal electrodes. Also, the driving circuit of the scanning electrode for supplying the scanning signal to the scanning electrode requires complicated signal processing to execute scanning by dividing the scanning electrode into two groups. Therefore, there are disadvantages that the size of the display device increases because the driving circuit becomes complicated, the number of elements of the electronic circuit increases, and the device cost increases. Moreover, the above liquid crystal display element has disadvantages in view of the operation stability that the response time is too long because of a large twist angle and display irregularity occurs due to a long time operation.

Liquid crystal display device with liquid crystal elastic constant ratio at least 1.75


A renewable biofuel based on a highly efficient batch catalysis methodology for conversion of 1-butene to a new class of potential jet fuel blends. By tuning the catalyst and then using the dimer produced, the carbon use is about 95% or greater.

We demonstrate that the quantitative conversion of 1-butene to a Schultz-Flory distribution of oligomers has been accomplished by use of Group 4 transition-metal catalysts in the presence of methylaluminoxane (MAO). The oligomerization reaction was carried out at ambient temperature in a sealed reaction vessel with complete conversion of 1-butene at catalyst turnover numbers greater than 17,000. The combination of high catalyst activity without concomitant production of high polymer led to a highly efficient production of new hydrocarbon jet fuel candidates. The reaction proceeds with high regioselectivity; however, because achiral catalysts were used, several diastereoisomeric structures were produced and observed in the gas chromatography-mass spectrometry (GC-MS) chromatograms. The single and specific dimer formed in the reaction, 2-ethyl-1-hexene, was easily removed by distillation and then was itself dimerized using acid catalysis to yield a mixture of mono-unsaturated C16 compounds. Changes in the oligomerization catalyst led to production of fuels with excellent cold-flow viscosity without the need for a high-temperature distillation. Thus, removal of the dimer followed by catalytic hydrogenation (PtO2) led to a 100% saturated hydrocarbon fuel with a density of 0.78 g/mL, a viscosity of 12.5 cSt at −20° C. (ASTM 445), and a calculated heat of combustion of 44+ MJ/kg. By back-addition of hydrogenated dimer in varying amounts (6.6, 11.5, and 17 wt %), it is possible to tailor the viscosity of the fuel (8.5, 7, and 6.5 cSt, respectively).
There exist several commercial and research programs around the world aimed at creating full-performance jet fuels based on alternative feedstocks. Traditionally, jet propulsion (JP) fuels contain a complicated array of saturated and aromatic hydrocarbons that are highly refined to meet fuel specifications for a particular application. For instance, the Navy's JP-5 has a significantly higher flash point (60° C.) in comparison to the Air Force JP-8 and commercial jet fuel (about 38° C.). (Corporan, E.; DeWitt, M. J.; Belovich, V.; Pawlik, R.; Lynch, A. C.; Gord, J. R.; Meyer, T. R. Energy Fuels 2007, 21, 2615-2626) (Chang, P. H.; Colbert, J. E.; Hardy, D. R.; Leonard, J. T. Prepr. Pap. Am Chem. Soc., Div. Pet. Chem. 2004, 49, 414). Syntroleum and Sasol have independently produced JP-5 and JP-8 equivalents based on gas-to-liquid (GTL) Fischer-Tropsch processes. (Feerks, R. L.; Muzzell, P. A. Prepr. Pap. Am Chem. Soc., Div. Pet. Chem 2004, 49, 407-410) (Muzzell, P. A.; Feerks, R. L.; Baltrus, J. P.; Link, D. D. Prepr. Pap. Am Chem. Soc., Div. Pet. Chem. 2004, 49, 411-413) and (Lamprecht, D. Energy Fuels 2007, 21, 1448-1453). One of the most challenging aspects to making a jet fuel using Fischer-Tropsch chemistry (Fischer, F.; Tropsch, H. Brennst. Chem. 1923, 4, 276) has been to meet the required coldflow properties. To date, this has required significant postprocessing or "reforming" of the fuel to increase the iso/normal paraffin product ratio. Typically, the Chevron isocracking technology produces a predominance of methyl branching at the 2 position of a hydrocarbon chain; however, the chemical product distribution is quite complicated.
Conversion of propene and butylenes to dimers/oligomers was one of the first commercial processes in the petroleum industry. (Schmerling, L.; Ipatieff, V. N. Adv. Catal. 1950, 21, 2). Some more recent approaches have looked at using mesoporous catalysts and newly designed large-pore acidic zeolite catalysts. (Catani, R.; Mandreoli, M.; Rossini, S.; Vaccari, A. Catal. Today 2002, 75, 125-131) (Schmidt, R.; Welch, M. B.; Randolph, B. B. Energy Fuels 2008, 22 (2), 1148-1155). Transition-metal catalysts (homo- and heterogeneous), generally grouped into the category of Ziegler-Natta (ZN), have enjoyed a successful history for converting olefins, in particular, ethylene and propene, into oligomeric and polymeric materials. (Natta, G. J. Polym. Sci. 1955, 16, 143) (Natta, G.; Pino, P.; Corradti, P.; Danusso, F.; Mantica, E.; Mazzanti, G.; Moraglio, G. J. Am. Chem. Soc. 1955, 77, 1708) (Natta, G. Angew. Chem. 1956, 12, 393. Ziegler, K. Angew. Chem. 1952, 64, 323) (Ziegler, K.; Holzkamp, E.; Breil, H.; Martin, H. Angew. Chem. 1955, 67, 541) (Janiak, C. Coord. Chem. ReV. 2006, 250, 66-94) (Belov, G. P. Petrol. Chem. 1994, 34, 105). Studies using 1-butene can involve a co-polymerization reaction with more reactive olefins, such as ethylene or propene. (Janiak, C.; Blank, F. Macromol. Symp. 2006, 236, 14-22). A study by Kaminsky explored the oligomerization of 1-butene using selected chiral Group 4 transition-metal catalysts and methylaluminoxane (MAO). (Kaminsky, W. Macromol. Symp. 1995, 89, 203-219). In general, the catalysts studied required elevated reaction temperatures and typically led to incomplete conversion of the 1-butene. A study by Christoffers and Bergman reported that using an aluminum/zirconium ratio of 1/1 and with a nearly stoichiometric amount of zirconium "catalyst" that 1-butene could be converted selectively to dimer (2-ethyl-1-hexene). (Christoffers, J.; Bergman, R. G. Inorg. Chim. Acta 1998, 270, 20).
In undertaking this research our goal was to create a full-performance JP-5/tactical biojet fuel that can be derived from a fully renewable and sustainable source of reduced carbon. Carbon dioxide is initially reduced via photosynthesis (e.g., cellulose and triglyceride oils). Further reduction can occur in a second fermentation or microbial treatment to afford an alternative biofuel and/or biofeedstock. (Wright, M. E.; Harvey, B. G.; Quintana, R. Prepr. Pap. Am. Chem. Soc., Fuel Div. 2008, 53 (1), 252-253.)
It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not to be viewed as being restrictive of the invention, as claimed. Further advantages of this invention will be apparent after a review of the following detailed description of the disclosed embodiments which are illustrated schematically in the accompanying drawings and in the appended claims.
It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not to be viewed as being restrictive of the invention, as claimed. Further advantages of this invention will be apparent after a review of the following detailed description of the disclosed embodiments, which are illustrated schematically in the accompanying drawings and in the appended claims.

Diesel and jet fuels based on the oligomerization of butene

The United States of America as represented by the Secretary of the Navy


A low temperature process for preparing an aromatic acid having formula (I),

The present invention provides a low temperature process for preparing an aromatic acid by reacting an aromatic aldehyde with air at a temperature of about 20xc2x0 C. to less than 100xc2x0 C. in the presence of a supported Group VIII metal catalyst.
4-Isopropylbenzoic acid (cumic acid or cuminic acid), which is an aromatic mono-carboxylic acid, is an important organic intermediate in the production of pharmaceutical compounds. For example, 4-isopropylbenzoic acid can be used to synthesize nateglinide, a compound for treating diabetes available under the trademark STARLIX from Novartis. Several methods have been used to prepare isopropylbenzoic acid from isopropylbenzaldehyde. Such methods typically employ deleterious oxidizing agents, such as peroxides, NaOCl, peracids, NaIO4, and O3 which can be used with or without a catalyst. The use of such oxidizing agents, however, pose safety concerns because they are corrosive, and disposing of such oxidizing agents may cause environmental problems, especially the by-product salts such as halogen-containing oxidants.
U.S. Pat. No. 3,946,067 describes a process for preparing benzaldehyde by vapor phase oxidation of toluene at a temperature from 100xc2x0 C. to 250xc2x0 C. in the presence of a catalyst composition containing phosphoric acid and a palladium metal. U.S. Pat. No. 5,693,856 describes a process for preparing terephthalic acid which involves reacting a polyalkyl benzene compound with oxygen in the presence of a heavy metal catalyst at a temperature from 150xc2x0 C. to 250xc2x0 C. U.S. Pat. No. 5,686,638 describes a process for preparing mono- or dicarboxylic acids from an aldehyde without using a catalyst or an aprotic solvent, which involves oxidizing the aldehyde in a carboxylic acid as diluent or carboxylic acid/water mixture.
U.S. Pat. No. 5,189,209 describes a process for preparing highly pure isophthalic acid which involves oxidizing m-dialkyl benzene with molecular oxygen in an acetic acid solvent in the presence of a heavy metal catalyst at a temperature of 100xc2x0 C. to 240xc2x0 C. to form crude isophthalic acid; and contacting the crude isophthalic acid with a Group VIII catalyst supported by activated carbon in the presence of hydrogen at a temperature of 170xc2x0 C. to 300xc2x0 C. U.S. Pat. No. 5,110,982 describes a process for producing 2,6-naphthalene dicarboxylic acid which involves oxidizing a 2-alkyl-6-acyl naphthalene with molecular oxygen-containing gas in the presence of a catalyst containing cobalt, manganese, and bromine in an acetic acid solvent. U.S. Pat. No. 4,603,220 describes a process for preparing aromatic monocarboxylic acids by oxidation of a liquid phase of toluene or substituted toluenes with oxygen or gas containing oxygen, and a heavy metal catalyst.
Japanese Patent No. 3038100 describes a process for preparing aromatic carboxylic acids by oxidation of aromatic aldehydes with a peracid. Japanese Patent Application No. 87-99169 describes preparing cuminic acid by oxidation of cuminaldehyde with hydrogen peroxide under alkaline conditions.
Air oxidation of 3,4-dimethoxybenzaldehyde to 3,4-dimethoxybenzoic acid using cobalt acetate, manganese acetate, or lithium bromide as catalysts and a reaction temperature of from 110xc2x0 C. to 140xc2x0 C. is described by Mukhopadhyay, Organic Process Research and Development, Vol. 3, pp. 365-369 (1999).
Therefore, it is desirable from a safety and environmental standpoint to develop a process for preparing an aromatic acid from an aromatic aldehyde that (i) does not involve the use of deleterious oxidizing agents; (ii) is essentially free of by-products; and (iii) is accomplished at a temperature of less than 100xc2x0 C.
The invention provides a low temperature process for preparing an aromatic acid having formula (I),
said process comprising reacting an aromatic aldehyde having formula (II)
with a gas having an oxygen content of 1 to 100 weight percent, based on the total weight of the gas, at a temperature of about 20xc2x0 C. to less than 100xc2x0 C. in the presence of a supported Group VIII metal catalyst, and a solvent having a flash point greater than 95xc2x0 C. and/or a melting point less than 55xc2x0 C., provided that the flash point of the solvent is greater than the reaction temperature, wherein R1 and R2 are independently selected from the group consisting of hydrogen and a C1-C8 linear, branched or cyclic alkyl group. Preferably the aromatic acid is 4-isopropylbenzoic acid and the aromatic aldehyde is 4-isopropylbenzaldehyde.
The process of the invention yields an aromatic acid in excellent yield, and (i) does not involve the use of deleterious oxidizing agents such as peroxides, NaOCl, peracids, NaIO4, and O3; (ii) is essentially free of by-products; and (iii) is accomplished at a temperature of less than 100xc2x0 C.

Air oxidation of an aromatic aldehyde to an aromatic acid

Abstract: with a gas having an oxygen content of 1 to 100 weight percent, based on the total weight of the gas, at a temperature of about 20xc2x0 C. to less than 100xc2x0 C. in the presence of a supported Group VIII metal catalyst, and a solvent having a flash point greater than 95xc2x0 C. and/or a melting point less than 55xc2x0 C., provided that the flash point of the solvent is greater than the reaction temperature, wherein R1 and R2 are independently selected from the group consisting of hydrogen and a C1-C8 linear, branched or cyclic alkyl group. The process of the invention yields an aromatic acid in excellent yield, and (i) does not involve the use of deleterious oxidizing agents; (ii) is essentially free of by-products; and (iii) is accomplished at a temperature of less than 100xc2x0 C.


Methods and devices for creating a supersaturated liquid solution having dissolved gas with hyperbaric partial pressures and aerosolizing the supersaturated solution via a nebulizer. High partial pressures of the dissolved gas may be maintained before, during, and after the aerosolization process. Thus, the hyperbaric partial pressures may be retained in the aerosol particles even after the particles are exposed to ambient barometric pressure. The aerosolized particles may be inhaled to improve oxygenation and blood flow to the lung or alternatively, the aerosolized particles can be topically applied to accelerate wound healing. Nebulizers may produce aerosol particles in some embodiments have mass median aerodynamic diameters of between about 0.25 and about 5 microns, thereby allowing sufficient deposition in the lung parenchyma, proximal to alveoli. Supersaturated dissolved oxygen aerosol particles having mass median aerodynamic diameters greater than 10 microns may be used to accelerate wound healing when combined with ultrasound.

Multiple cardiopulmonary diseases result in tissue hypoxia, which is a deficiency of molecular oxygen available for cellular metabolism. Tissue hypoxia may have many causes, and treatment of hypoxia is conventionally directed to the cause of the hypoxia.
When hypoxia is caused by deficiencies in the partial pressure of oxygen in inspired gas diffusing across the alveolar capillary membrane in the lung, the treatment involves increasing the partial pressure of inspired oxygen in the inspired atmosphere. Conditions such as asthma, pneumonia, and adult respiratory distress syndrome are examples of diseases which may produce tissue hypoxia because of complex pathology within the lung.
Treatment of tissue hypoxia associated with these diseases may be accomplished via multiple devices such as masks, nasal cannula, endotracheal tubes, tracheostomy tubes, mechanical ventilators and various other devices that administer oxygen. However, because of lung pathologic states such as mucosal edema, atelectasis, and bronchoconstriction, gaseous oxygen inhalation with the aforementioned devices may insufficiently treat tissue hypoxia. In addition, the inhalation of gaseous oxygen may result in oxygen toxicity and barotrauma, when excessive concentrations and gas partial pressure is used during treatment.
Tissue hypoxia may occur when blood flow to the lung is altered or decreased, thereby mismatching ventilated lung units with perfused lung units. Conditions such as primary pulmonary hypertension, and adult respiratory distress syndrome are examples of conditions which may decrease blood flow due to pulmonary artery vasoconstriction. Medications which may be administered to treat these types of lung problems may include inhalation of gaseous nitric oxide which is intended to dilate the vasculature, decrease pulmonary vascular resistance, and improve lung blood flow. Ideally, the inhalation of gaseous nitric oxide would improve the matching of ventilation with perfusion in the lung and result in improved gas exchange. However, the inhalation of nitric oxide may be associated with several complications including methemoglobinemia, rebound vasoconstriction during weaning of the gas, and hypotension. In addition, nitric oxide is an extremely expensive treatment, and may require extended periods of gas inhalation at considerable cost.

Devices and methods for aerosol therapy using hyperbaric tonometry


An electrophotographic recording apparatus comprising a rotatable photosensitive drum and unit for electrifying the drum, depositing an electrostatic latent image on the drum, developing the latent image, transferring the image on the drum to printing paper, and optical-deelectrifying the drum. In this method, the optical deelectrification unit is located at a position opposite to the drum with respect to a passage of the printing paper, and an optical deelectrification beam is irradiated to the drum only when the printing paper interrupts an optical path of the deelectrification light toward the drum.

1. Field of the Invention
This invention relates to a method of controlling an optical-deelectrification in an electrophotographic recording apparatus, such as a printer, facsimile, or copying machine, having a photosensitive drum which is deelectrified by an optical irradiation thereto. This invention also relates to a method of pre-electrification in the same kind of electrophotographic recording apparatus.
2. Description of the Related Art
An electrophotgraphic recording apparatus is widely used in various printers, facsimiles, or copying machines, and such an electrophotgraphic recording apparatus includes many processing units, such as a photosensitive drum, a front electrification unit, a developing unit, a photo-depositing unit, a deelectrification unit, and a cleaner, and therefore, such an apparatus must have a large size. On the other hand, there is a strong demand for a reduction of the size of such an apparatus due to the current trend toward smaller office automation facilities.
To reduce the size of such an electrophotographic recording apparatus, the respective processing units must be made compact and effectively arranged in the apparatus, and in this connection, a deelectrification unit can be more freely arranged than other units. Therefore, there is a demand for a small-sized optical-deelectrification unit. Note, this unit must be sometimes arranged at a position from which an optical-deelectrification beam is not directly irradiated to the photosensitive drum, but is irradiated to the drum via a printing media.

Method of deelectrification in an electrophotographic apparatus