Edge termination for a silicon carbide Schottky rectifier is provided by including a silicon carbide epitaxial region on a voltage blocking layer of the Schottky rectifier and adjacent a Schottky contact of the silicon carbide Schottky rectifier. The silicon carbide epitaxial layer may have a thickness and a doping level so as to provide a charge in the silicon carbide epitaxial region based on the surface doping of the blocking layer. The silicon carbide epitaxial region may form a non-ohmic contact with the Schottky contact. The silicon carbide epitaxial region may have a width of from about 1.5 to about 5 times the thickness of the blocking layer. Schottky rectifiers with such edge termination and methods of fabricating such edge termination and such rectifiers are also provided. Such methods may also advantageously improve the performance of the resulting devices and may simplify the fabrication process.

The present invention relates microelectronic devices and more particularly to edge termination for silicon carbide Schottky devices.
High voltage silicon carbide (SiC) Schottky diodes, which can handle voltages between 600 V and 2.5 kV, are expected to compete with silicon PIN diodes fabricated of similar voltage ratings. Such diodes may handle as much as 100 amps of current, depending on their active area. High voltage Schottky diodes have a number of important applications, particularly in the field of power conditioning, distribution and control.
An important characteristic of a SiC Schottky diode in such applications is its switching speed. Silicon-based PIN devices typically exhibit relatively poor switching speeds. A silicon PIN diode may have a maximum switching speed of approximately 20 kHz, depending on its voltage rating. In contrast, silicon carbide-based devices are theoretically capable of much higher switching speeds, for example, in excess of 100 times better than silicon. In addition, silicon carbide devices may be capable of handling a higher current density than silicon devices.
However, reliable fabrication of silicon carbide-based Schottky devices may be difficult. Typical edge termination in SiC Schottky diodes require ion implantation of p-type dopants into the crystal. Such implants may cause substantial damage to the crystal lattice, which may require high temperature annealing to repair such defects. This high-temperature anneal step ( greater than 1500xc2x0 C.) may be undesirable for a number of reasons. For example, high temperature anneals tend to degrade the surface of SiC on which the Schottky contact is to be made, as silicon tends to dissociate from exposed surfaces of the crystal under such a high-temperature anneal. Loss of silicon in this manner may result in a reduced quality Schottky contact between metal and the semiconductor surface. High temperature anneals have other drawbacks as well. Namely, they are typically time-consuming and expensive. Moreover, implantation of p-type (Al) dopants may cause substantial lattice damage, while other species (B) have poor activation rates.
A conventional SiC Schottky diode structure has an n-type SiC substrate on which an nxe2x88x92 epitaxial layer, which functions as a drift region, is formed. The device typically includes a Schottky contact formed directly on the nxe2x88x92 layer. Surrounding the Schottky contact is a p-type JTE (junction termination extension) region which is typically formed by ion implantation. The implants may be aluminum, boron, or any other suitable p-type dopant. The purpose of the JTE region is to prevent the electric field crowding at the edges, and to prevent the depletion region from interacting with the surface of the device. Surface effects may cause the depletion region to spread unevenly, which may adversely affect the breakdown voltage of the device. Other termination techniques include guard rings and floating field rings which are more strongly influenced by surface effects. A channel stop region may also be formed by implantation of n-type dopants such as Nitrogen or Phosphorus in order to prevent the depletion region from extending to the edge of the device.
Additional conventional termination of SiC Schottky diodes are described in xe2x80x9cPlanar Terminations in 4H-SiC Schottky Diodes With Low Leakage And High Yieldsxe2x80x9d by Singh et al., ISPSD ""97, pp. 157-160. A p-type epitaxy guard ring termination for a SiC Schottky Barrier Diode is described in xe2x80x9cThe Guard-Ring Termination for High-Voltage SiC Schottky Barrier Diodesxe2x80x9d by Ueno et al., IEEE Electron Device Letters, Vol. 16, No. 7, July, 1995, pp. 331-332. Additionally, other termination techniques are described in published PCT Application No. WO 97/08754 entitled xe2x80x9cSiC Semiconductor Device Comprising A PN Junction With A Voltage Absorbing Edge.xe2x80x9d
Embodiments of the present invention may provide a silicon carbide Schottky rectifier having a silicon carbide voltage blocking layer having a predefined surface doping level and a Schottky contact on the silicon carbide voltage blocking layer. A silicon carbide epitaxial region is also provided on the silicon carbide voltage blocking layer and adjacent the Schottky contact. The silicon carbide epitaxial region has a thickness and a doping level designed to provide a selected charge per unit area in the silicon carbide epitaxial region. The charge per unit area in the silicon carbide epitaxial regions, also referred to as the junction termination extension (JTE) charge, is selected based on the surface doping of the blocking layer. In particular embodiments, the JTE charge is greater than 50% of an optimal JTE charge as determined by the surface doping of the blocking layer. Furthermore, it is preferred that the JTE charge is not greater than the optimal charge value.
In further embodiments of the present invention, a silicon carbide Schottky rectifier is provided having a silicon carbide voltage blocking layer and a Schottky contact on the silicon carbide voltage blocking layer. A silicon carbide epitaxial termination region is provided on the voltage blocking layer and adjacent the Schottky contact. The product of the thickness and doping concentration of the silicon carbide epitaxial region is greater than about 50% of             (                        ϵ          r                xc3x97                  ϵ          0                xc3x97                  E          C                    )        q    ;
where:
xcex5r is the relative dielectric constant of SiC;
xcex50 is dielectric constant of air;
EC is the critical electric field of SiC; and
q is the electronic charge.
In further embodiments, the product of the thickness and doping concentration are not greater than about 100% of             (                        ϵ          r                xc3x97                  ϵ          0                xc3x97                  E          C                    )        q    .
In still further embodiments, the thickness and doping concentration are not less than about 75% of             (                        ϵ          r                xc3x97                  ϵ          0                xc3x97                  E          C                    )        q    .
In still further embodiments of the present invention, the silicon carbide epitaxial region extends from the Schottky contact from about 1.5 to about 5 times the thickness of the blocking layer. Additionally, a non-ohmic contact may be provided between the silicon carbide epitaxial termination region and the Schottky contact.
In embodiments of the present invention where the silicon carbide epitaxial region has a first conductivity type and the voltage blocking layer has a second conductivity type opposite the first conductivity type, the edge termination may also include a region of first conductivity type silicon carbide in the voltage blocking layer having a carrier concentration higher than that of the voltage blocking layer and adjacent a periphery of the silicon carbide epitaxial region opposite the Schottky contact.
In additional embodiments of the present invention, the Schottky rectifier may also include a first layer of silicon carbide of a first conductivity type the same as a conductivity type of the blocking layer and disposed between the blocking layer and a silicon carbide substrate. The first layer of silicon carbide may have a carrier concentration higher than the blocking layer. A second layer of silicon carbide of the first conductivity type may also be provided on the substrate opposite the first layer of silicon carbide so as to provide a layer of silicon carbide having a carrier concentration higher than a carrier concentration of the substrate. An ohmic contact may be provided on the second layer of silicon carbide. In such embodiments, the second layer may be an implanted layer of first conductivity type silicon carbide. Furthermore, the silicon carbide epitaxial region may be of a second conductivity type opposite that of the first conductivity type. In particular, the first conductivity type may be n-type and the second conductivity type may be p-type.
In other embodiments of the present invention, a Schottky rectifier is provided which includes an n-type silicon carbide substrate, an n-type silicon carbide blocking layer on the silicon carbide substrate, a Schottky contact on the silicon carbide blocking layer, an epitaxial region of p-type silicon carbide on the silicon carbide blocking layer and adjacent the Schottky contact so as to form a non-ohmic contact between the p-type epitaxial region and the Schottky contact, and an ohmic contact on the substrate opposite the blocking layer.
In further embodiments of the present invention, a plurality of p-type silicon carbide islands on the blocking layer may be provided. In such embodiments, the Schottky contact overlaps the plurality of p-type islands.
In yet other embodiments of the present invention, a Schottky rectifier is provided which includes an n-type silicon carbide substrate, an n-type silicon carbide blocking layer on the silicon carbide substrate, a Schottky contact on the silicon carbide blocking layer, an epitaxial region of p-type silicon carbide on the silicon carbide blocking layer and adjacent the Schottky contact so as to form a non-ohmic contact between the p-type epitaxial region and the Schottky contact and an ohmic contact on the substrate opposite the blocking layer. The p-type silicon carbide epitaxial region extends from the Schottky from contact about 2 to about 3 times the thickness of the blocking layer. Such embodiments may also include a plurality of p-type silicon carbide islands on the blocking layer. If so, then the Schottky contact overlaps the plurality of p-type islands.
In method embodiments of the present invention, a method of fabricating a termination region of a silicon carbide Schottky rectifier includes forming an epitaxial layer of p-type silicon carbide having a thickness and a doping level selected so as to provide a charge in a region of p-type silicon carbide adjacent to a Schottky contact of the Schottky rectifier proportional to the surface doping of a silicon carbide blocking layer of the Schottky rectifier and patterning the epitaxial layer of p-type silicon carbide so as to provide the region of p-type silicon carbide adjacent to the Schottky contact of the Schottky rectifier.
In such method embodiments, the patterning the epitaxial layer of p-type silicon carbide may be provided by forming an oxide layer on the p-type epitaxial layer of silicon carbide, patterning the oxide layer so as to expose a portion of the p-type epitaxial layer corresponding to the Schottky contact, thermally oxidizing the exposed portion of the p-type epitaxial layer at a temperature and for a time sufficient to consume all of the expose portion of the p-type epitaxial layer, and etching the thermally oxidized portion of the p-type epitaxial layer so as to expose a portion of the blocking layer on which the Schottky contact is formed. Furthermore, thermally oxidizing the p-type epitaxial layer may be carried out in a dry ambient environment. Additionally, thermally oxidizing the p-type epitaxial layer may be accomplished by oxidizing the p-type epitaxial layer at a temperature of less than about 1300xc2x0 C.
In further embodiments, etching the thermally oxidized portion of the p-type epitaxial layer may be preceded depositing an ohmic metal on a surface of a silicon carbide substrate opposite the blocking layer and annealing the ohmic metal so as to form an ohmic contact to the silicon carbide substrate. Such a deposition of an ohmic metal may also be preceded by implanting n-type dopants in the substrate so as to form a region of n-type silicon carbide having a carrier concentration higher than a carrier concentration of the substrate. In such embodiments, the ohmic metal may be deposited on the implanted region of the substrate. Furthermore, the implantation of n-type dopants may be carried out prior to thermally oxidizing the exposed portion of the p-type epitaxial layer such that thermally oxidizing the exposed portion of the p-type epitaxial layer also activates the n-type dopants.
In yet other embodiments of the present invention, etching the thermally oxidized portion of the p-type epitaxial layer is followed by depositing a Schottky metal on the exposed portion of the blocking layer.
In still other embodiments of the present invention, the good quality passivating oxide layer is patterned so as to expose a portion of the p-type epitaxial layer corresponding to the Schottky contact including a plurality of regions of exposed portions of the p-type epitaxial layer. The exposed portion of the p-type epitaxial layer including the plurality of regions is thermally oxidized at a temperature and for a time sufficient to consume all of the exposed portion of the p-type epitaxial layer. The thermally oxidized portion of the p-type epitaxial layer is etched so as to expose a portion of the blocking layer on which the Schottky contact is formed thereby providing a plurality of exposed portions of the blocking layer spaced apart by islands of p-type silicon carbide.
In additional embodiments of the present invention, patterning the oxide layer so as to expose a portion of the p-type epitaxial layer corresponding to the Schottky contact is preceded by patterning the oxide layer and the p-type epitaxial layer to expose a portion of the blocking layer at the periphery of the Schottky rectifier, and implanting n-type dopants in the exposed portion of the n-type blocking layer so as to provide a region of implanted n-type dopants adjacent the periphery of the p-type epitaxial layer.
In particular embodiments, the thickness and doping level of the silicon carbide epitaxial region are selected so as to provide a charge in the region of p-type silicon carbide adjacent to a Schottky contact of the Schottky rectifier which is from about 50% to about 100% of             Q              JTE        ,        opt              =                  (                              ϵ            r                    xc3x97                      ϵ            0                    xc3x97                      E            C                          )            q        ;
where:
QjTE,opt is the optimum JTE charge;
xcex5r is the relative dielectric constant of SiC;
xcex50 is dielectric const. of air;
EC is the critical electric field of SiC; and
q is the electronic charge.
Furthermore, the thickness and doping level may be about 75% of       Q          JTE      ,      opt        =                    (                              ϵ            r                    xc3x97                      ϵ            0                    xc3x97                      E            C                          )            q        .
In further method embodiments of the present invention, a method of fabricating a silicon carbide Schottky rectifier is provided by forming a first n-type silicon carbide epitaxial layer on an n-type silicon carbide substrate, wherein the first n-type silicon carbide epitaxial layer has a carrier concentration less than a carrier concentration of the silicon carbide substrate. A p-type silicon carbide epitaxial layer is formed on the first n-type epitaxial layer. A passivating oxide is deposited on the p-type silicon carbide epitaxial layer and the passivating oxide patterned to expose a portion of the p-type silicon carbide corresponding to a Schottky contact of the Schottky rectifier. The exposed portion of the p-type silicon carbide is thermally oxidized to oxidize the p-type silicon carbide to the first n-type epitaxial layer. An ohmic contact metal is then deposited on the substrate opposite the first n-type epitaxial layer and annealed so as to provide an ohmic contact to the substrate. Then the oxidized p-type silicon carbide is removed to expose a portion of the first n-type epitaxial layer corresponding to the Schottky contact and a Schottky metal deposited on the exposed portion of the first n-type epitaxial layer so as to provide a Schottky contact to the first n-type epitaxial layer.
In further embodiments of the present invention, the p-type silicon carbide epitaxial layer has a thickness and a doping level selected so as to provide a charge in a region of p-type silicon carbide adjacent to the Schottky contact of the Schottky rectifier proportional to the surface doping of the first n-type epitaxial layer.
In other embodiments, the method further includes forming a second layer of n-type silicon carbide, wherein the second layer of n-type silicon carbide is disposed between the silicon carbide substrate and the first n-type epitaxial layer and has a carrier concentration higher than the carrier concentration of the silicon carbide substrate.
In still other embodiments, the method may also include patterning the p-type epitaxial layer to expose a portion of the first n-type epitaxial layer adjacent the periphery of the Schottky rectifier, implanting n-type dopants in the exposed portion of the first n-type epitaxial layer and thermally annealing the implanted dopants so as to activate the dopants. In such embodiments, the deposition of a passivating oxide may also include depositing a passivating oxide on the p-type epitaxial layer and the implanted region of the first n-type epitaxial layer. In particular embodiments, the thermal anneal of the implanted dopants is carried out at a temperature of less than about 1300xc2x0 C.
Furthermore, additional method embodiments may also include implanting n-type dopants in the silicon carbide substrate opposite the first n-type epitaxial layer so as to provide a region of n-type silicon carbide having a carrier concentration higher than the carrier concentration of the silicon carbide substrate. In such embodiments, implanting n-type dopants may be followed by depositing an oxide on the implanted region of the silicon carbide substrate and the thermal oxidation step may be followed by removing the oxide from the implanted region of the silicon carbide substrate.
The advantages and features of the invention, and the manner in which the same are accomplished, will become more readily apparent upon consideration of the following detailed description of the invention taken in conjunction with the accompanying drawings, which illustrate preferred and exemplary embodiments, and wherein:

Epitaxial edge termination for silicon carbide Schottky devices and methods of fabricating silicon carbide devices incorporating same


A portable antenna with a collapsible reflector dish made from a flexible mesh so that the reflector can be folded in upon itself from the deployed position. When closed, the antenna is contained within an outer casing. The outer casing has a top side that opens when the antenna is deployed. Depending upon the specific application, the top side of the outer casing may be flat or conical. The antenna can be deployed by remote element. The driving element extends the support frame for the reflector dish to its deployed position, and raises the boom into its operating position.

In view of the fact that the field of communications technology is as widespread as it is today, it is not surprising that there would be a large body of prior art relative to antennas.
The field of the present invention is that of portable antennas, and more particularly portable, collapsible, and deployable antennas. These devices are most useful in applications where space is at a premium, such as in satellites, where using an antenna with a large fixed reflector dish is impractical. To address this situation, many structures for antennas with collapsible reflector dishes have been patented.
The prior art is universally addressed to means of collapsing reflector panels, usually rigid, around a central rigid boom. Examples of the prior art are the "FOLDABLE REFLECTOR" of Higgins, et al., U.S. Pat. No. 5,198,832; "FOLDING DISH REFLECTOR" of Robert Luly, U.S. Pat. No. 4,683,475; "COLLAPSIBLE ANTENNA" of Manfred Westphal, U.S. Pat. No. 4,899,167; "DEPLOYABLE OFFSET DISH STRUCTURE" of Palmer, et al., U.S. Pat. No. 4,862,190; "UNFOLDABLE ANTENNA REFLECTOR" of Herbig, et al., U.S. Pat. No. 4,642,652; and "PORTABLE ANTENNA WITH WEDGE-SHAPED REFLECTIVE PANELS", of Gonzalez, U.S. Pat. No. 4,506,271.
At least one reference describes a collapsible dish without specifying a rigid boom, the "COLLAPSIBLE APPARATUS FOR FORMING A DISH SHAPED SURFACE" of Pappas et al., U.S. Pat. No. 5,255,006. This device does retain the use of rigid elements for the dish itself.
There are some references in the prior art which have recognized the desirability of using flexible panels for the components of the antenna reflector. Examples of this particular advancement are "UNFURLABLE MESH REFLECTOR" of Chang, et al., U.S. Pat. No. 4,989,015; and "FOLDABLE ANTENNA REFLECTOR" of Gilles Labruyere, U.S. Pat. No. 4,352,113.
All these prior art devices have as a limitation the fact that they can collapse only around a central boom or central axis, and thus are not of an optimum configuration to minimize storage space requirements.

Stowable, deployable, retractable antenna


Motorized carriage (1) that is able to move in translation along a longitudinal axis (X) along a horizontal rail, said carriage (1) comprising at least one wheel (4), in particular of the friction wheel type, that is driven in rotation by an electric motor (5) and is mounted so as to pivot about a transverse axis (Y) on a holder (3) which carries said motor (5), said carriage (1) comprising a chassis (2) incorporating guide means (23, 24) mounted so as to slide on the chassis (2) along a vertical axis (Z) orthogonal to the longitudinal axis (X) and transverse axis (Y) and cooperating with elastic stressing means (25, 26) that are designed to move the guide means (23, 24) in the direction of the rail, where the holder (3) is in sliding contact with said guide means (23, 24) along the longitudinal axis (X) and vertical axis (Z), this sliding contact being designed to convert a movement of the holder (3) along the longitudinal axis (X) into a concurrent movement of the holder (3) along the vertical axis (Z) in the direction of the rail. Said carriage (1) can be used in video surveillance systems.

The invention finds a particular, but non-limiting, application in the field of video surveillance systems integrating a suspended carriage movable in translation on a horizontal rail, where the carriage supports at least one camera mounted on its frame.
In the field of motorized carriages, the wheel(s) is/are driven in rotation by the electric motor and roll(s) and remain(s) in contact on the horizontal rail. When rolling, each wheel applies a force along a vertical axis (perpendicular to the rail) and, in a conventional manner, a balance is sought between the adherence and the pressure of each rail on the rail.
Indeed, a low pressure allows limiting the noise and the wear of the components (in particular of the wheels) but limits the adherence of the wheel on the rail, resulting in a risk of skidding of the wheel and consequently in a loss of the driveability of the carriage.
Conversely, a significant pressure of the wheel guarantees the adherence but generates rapid noise and a wearing of the components (in particular of the wheels). Moreover, with a high pressure of the wheel on the rail, part of the energy deployed by the motor is used to overcome the deformation of the materials, thereby an overconsumption of energy.
Furthermore, retaining either one of the two solutions, the low-pressure solution (in order to gain silence, limit wear and energy consumption) or the high-pressure solution (in order to enhance adherence and driveability), ultimately turns out to be limited because the rail often presents dimensions subject to variations, even slight variations, and such variations of the dimensions ineluctably make the pressure of the wheel on the rail vary.

Motorized carriage that is movable in translation on a rail


This disk loading device is capable of reproducing a plurality of disks. A power transmission to drive gears is switched by tooth omission gears of a control gear so that angular movement of a disk playing portion, as well as movement of a tray base in a non-reproducing position and a reproducing position of the disk playing portion, can be effected by a single motor. A close lock gear, which prevents movement of the tray base in a disk reception stop positions, limits position of the drive gears. With this arrangement, when each tooth omission gear of the control gear enters the teeth of the corresponding drive gear, the interference of the teeth is eliminated. With this construction, the number of component parts such as a drive motor is reduced, thereby achieving a compact design and a stable operation.

This invention relates to a disk loading device for a disk player of the type which can be loaded with a plurality of disks, can continuously play the disks, and can play a desired one of the disks and a desired music track.
In recent years, a disk loading device, capable of being loaded with a plurality of disks for reproduction or playback, is of such a construction that even when one of the loaded disks is being reproduced, other loaded disks can be exchanged.
One such conventional disk loading device of the type described above will now be described with reference to the drawings.
FIG. 17 is an exploded, perspective view of a conventional disk loading device, FIG. 18 is a cross-sectional view taken along the line XVIII--XVIII of FIG. 17, and FIG. 19 is a cross-sectional view taken along the line IXX--IXX of FIG. 17.
In FIGS. 17 to 19, a tray base 50 is received in a hole 51a formed in a panel chassis 51, and right and left guide portions 50a on the tray base 50 are fitted respectively on right and left ribs 51b formed on the panel chassis 51, so that the tray base 50 is movable along the ribs 51b in directions indicated by arrows A and B. Right and left holder plates 52 are engaged respectively with opposite sides 50b of the tray base 50 to limit an upward movement of the tray base 50 (that is, to limit a vertical play), and are fixedly secured to the panel chassis 51.
As shown in FIG. 18, a rotary tray 53 has a rib 53c which is engaged with an outer periphery 54b of each of three rollers 54 each having a shaft portion 54a rotatably supported by a pawl 50c, a reception rib 50d and a hole 50i which are provided in the tray base 50. A hole 53d in the rotary tray 53 fits on a shaft 50e of the tray base 50, so that the rotary tray 53 is rotatable in directions indicated by arrows C and D. A notch 53b is formed in a central portion of each of five disk placing portions 53a. At this time, the roller 54 can not be seen through the notch 53b in the rotary tray 53 (see a portion designated at L1 in FIG. 18).
A motor 55 mounted on the tray base 50 drives the rotary tray 53 through a speed reduction mechanism which comprises a motor pulley 56, a belt 57, a worm pulley 58, a worm shaft 59 and a worm 60. More specifically, teeth 60a of the worm 60 drive a toothed portion 53e of the rotary tray 53 to rotate the rotary tray 53 in directions indicated by arrows C and D. As shown in FIG. 19, the worm 60, together with the worm pulley 58, is press fitted on the worm shaft 59, and the worm shaft 59 is rotatably mounted on bearing portions 50f on the tray base 50. Reference numeral 61 denotes a disk.
A motor 62 mounted on the panel chassis 51 drives the tray base 50 through a speed reduction mechanism which comprises a motor pulley 63, a belt 64, a pulley gear 65 and a drive gear 66. More specifically, a toothed portion 66a of the drive gear 66 drives a rack 50g, provided on the lower surface of the tray base 50, to move the tray base 50 in the directions of arrows A and B.
Referring to a disk playing portion 67, a turntable 67a is adapted to carry the disk 61 placed on the rotary tray 53, and a shaft 67b is mounted on support portions 51c on the panel chassis 51 so that the disk playing portion 67 can be pivotally moved in directions indicated by arrows E and F. A pin 67c is engaged with a cam portion 68a of an elevator gear 68, and the rotation of the elevator gear 68 causes the disk playing portion 67 to move in the directions of arrows E and F.
A motor 69 rotates the elevator gear 68 through a speed reduction mechanism which comprises a motor pulley 70, a belt 71 and a pulley gear 72.
A clamper 73 holds the disk 61 between it and the turntable 67a of the disk playing portion 67 which passes along the notch 53b in the rotary tray 53, the clamper 73 being rotatably mounted in a hole 74a formed through a clamp plate 74 mounted on the panel chassis 51. The tray base 50 has an opening 50h into which the disk playing portion 67 moves.
The operation of the above disk loading device will now be described. First, when an instruction is given for bringing the tray base 50 and the rotary tray 53 to the exterior of the panel chassis 52 (that is, into a disk attachment/detachment position) in order to place the disks 61 on the rotary tray 53, the motor 62 rotates and transmits its rotational force through the speed reduction mechanism which comprises the motor pulley 63, the belt 64, the pulley gear 65 and the drive gear 66, and therefore the toothed portion 66a of the drive gear 66 drives the rack 50g of the tray base 50 in the direction A, so that the tray base 50 moves in the direction A and stops at the disk attachment/detachment position, with the disk placing portions 53a of the rotary tray 53 disposed exteriorly of the panel chassis 51. Even at this time, the tray base 50 is held at its opposite sides 50b by the holder plates 52, and therefore its upward movement (that is, a vertical play) is limited.
Then, disks 61 are placed on the respective disk placing portions 53a of the rotary tray 53. In this embodiment, two disks 61 can be placed at a time. Then, when other disks are to be placed respectively on the other disk placing portions 53a, the motor 55 rotates in accordance with an instruction, and transmits its rotational force through the speed reduction mechanism which comprises the motor pulley 56, the belt 57, the worm pulley 58, the worm shaft 59 and the worm 60, and therefore the teeth 60a of the worm 60 drive the toothed portion 53e of the rotary tray 53 in the direction of arrows C-D, so that the rotary tray 53 is rotated together with the rollers 54 in the direction of arrows C-D from one disk placing portion 53a to the next one.
The rotary tray 53 is stopped with that disk placing portion 53a on which the disk 61 has not yet been placed is disposed exteriorly of the panel chassis 51, and another disk can be placed on that disk placing portion 53a. This operation is repeated so that the disks 61 can be placed on all of the disk placing portions 53a, respectively.
Then, when an instruction is given for playing the disk 61, the motor 62 rotates in a direction opposite to the above-mentioned direction, and therefore the tray base 50 also moves in a direction (i.e., the direction of arrow B) opposite to the above-mentioned direction and is stopped at a disk reception position where the tray base 50 is received within the panel chassis 51.
Then, the motor 55 rotates to move the disk 61 to be played to a playing position, so that the rotary tray 53 rotates toward the playing position in the direction of arrows C-D and stops when the designated disk 61 is brought into the playing position beneath the clamper 73. Then, the motor 69 rotates to rotate the elevator gear 68 through the speed reduction mechanism which comprises the motor pulley 70, the belt 71 and the pulley gear 72, so that the cam portion 68a of the elevator gear 68 moves the pin 67c of the disk playing portion 67, and therefore the disk playing portion 67 is pivotally moved in the direction of arrow E, so that the disk 61 is carried between the turntable 67a and the clamper 73, thereby starting the disk playing.
Then, when the playing is finished, the motor 69 rotates in the direction opposite to the above-mentioned direction in order to play the next disk 61, and therefore the disk playing portion 67 is pivotally moved in the direction of arrow F. Then, the rotary tray 53 is rotated in the direction of arrow C-D by the rotation of the motor 55 to move the next disk 61 into the playing position, and the disk playing portion 67 is pivotally moved in the direction of arrow E to play the disk 61, as described above. By repeating this operation, all of the disks 61 placed on the rotary tray 53 can be played.
Then, when the disk 61 is to be exchanged or taken out after the playing of this disk is finished, an instruction is given to rotate the motor 69 to pivotally move the disk playing portion 67 in the direction of arrow F, and then the tray base 50 is moved in the direction of arrow A by the rotation of the motor 62 to bring the disk 61, placed on the rotary tray 53, to the exterior of the panel chassis 51 (i.e., the disk attachment/detachment position). Then, the motor 55 is rotated in accordance with an instruction to rotate the rotary tray 53 so as to exchange or take out the disk 61.
When it is desired to exchange or take out another disk 61 while the disk 61 is played, an instruction is given to rotate the motor 62 to move the tray base 50 in the direction of arrow A, so that the disk 61 placed on the rotary tray 53 is brought to the exterior of the panel chassis 51 (i.e., the disk attachment/detachment position). Then, an instruction is given to rotate the motor 55 to rotate the rotary tray 53, and during this time, the disk or disks 61 other than the disk in the process of playing can be exchanged or taken out.
However, in the above conventional disk loading device, in order that another disk 61 can be exchanged or taken out during the time when one disk 61 is played, the three drive systems including the motors 55, 62 and 69, respectively, are needed, and therefore the number of the component parts is increased. This has been a barrier to a compact design of the disk loading device.

Single motor disk loading device with lock gear

Matsushita Electric Industrial Co., Ltd.


A non-contact power feeding coil provided with a coil; and a core that forms a part of a circulating magnetic path that is interlinked to the coil, and used in at least one of a power feeding-side device and a power receiving-side device of a non-contact power feeding system, in which the core is configured to connect three or more core units in one row, and the core units include one or more interlinked core units that are interlinked to the coil and two non-interlinked core units that are not interlinked to the coil respectively disposed on both ends in the connection direction of the one or more interlinked core units. Thereby, it is possible to provide a non-contact power feeding coil that suppresses an increase in leakage flux.

A solder printing machine, a component mounting machine, a reflow machine, a board inspection machine, and the like may be used as a board production machine for producing a board on which multiple components are mounted. Typically, the equipment is connected and is constituted by a board production line. Furthermore, in many cases a board production line is configured by arranging board production machines modularized at the same size. Setup changing work is easy during line recombination or during extension in which a line is lengthened by using a modularized board production machine, and a flexible board production line is realized.
In recent years, promoting labor saving and automation by machinery or members used by each board production machine of the board production line being conveyed to a moving body that moves along the board production line has been investigated. Furthermore, as power supply means to the moving body, a non-contact power feeding system is considered that sets a board production line as a power feeding-side device and sets the moving body as a power receiving-side device. Note that, application of the non-contact power feeding system is not limited to a board production line, and covers a wide range of fields including assembly lines and processing lines that produce other products, power supply during running of electric vehicles, and the like. A technical example which relates to this type of non-contact power feeding system is disclosed in PTL 1 to PTL 3.
PTL 1 discloses a pickup coil unit that generates an induced electromotive force based on current that is supplied to a feeder. The pickup coil unit forms a core around which a pickup coil is wound by joining multiple core pieces, and forms a positioning section on a joining surface of the core pieces. Then, the number of core piece joins is selected according to power feeding capacity. Thereby, it is possible to simply assemble and easily change the power feeding capacity of the pickup unit. Furthermore, the embodiment discloses using an E-type core as the core piece.
A non-contact power feeding device in PTL 2 has a similar configuration to PTL 1 and is characterized by displaceably providing a partition plate that determines a position of a coil that configures a power receiving coil. Thereby, it is possible to reduce influence of leakage flux from the end portion of a core leg section on the power receiving coil and it is possible to enhance the power receiving efficiency. Furthermore, the embodiment discloses that it is also possible to adopt a C-type core and not only an E-type core as the core.
PTL 3 discloses a non-contact power feeding device that is provided with a pickup portion that is inductively coupled to a feeder through which a high frequency current flows. The pickup portion is configured so as to be provided with a connection core and an end face core that have a cut coil, respectively, and when the connection core and the end face core are connected, the cut coils are coupled. Thereby, it is possible to simply adjust an output voltage by connecting the end face core to the end face of the connection core.

Non-contact power feeding coil and non-contact power feeding system


A refrigeration unit of the type having an economizer cycle driven by a prime mover cooled by a liquid coolant. Electrical control configures refrigerant flow paths of the unit to provide heating and cooling cycles, as required to control the temperature of a conditioned space to a predetermined set point temperature. Heat from the liquid coolant is used to enhance the heating cycle. A heating cycle is initiated immediately, when required, when the temperature of the liquid coolant is above a predetermined temperature. A heating cycle is delayed by a special refrigeration cycle which increases the load on the prime mover, when the temperature of the liquid coolant is not above the predetermined temperature. In a preferred embodiment of the invention, the special refrigeration cycle provides simultaneous heating and cooling cycles, which include evaporating liquid refrigerant in an evaporator associated with the conditioned space, as in a cooling cycle, while condensing hot gas refrigerant from the compressor in a condenser associated with the conditioned space, as in a heating cycle.

U.S. Pat. No. 4,850,197, which is assigned to the same assignee as the present application, discloses a vapor compression refrigeration unit based on an economizer cycle which utilizes a refrigerant compressor having an intermediate pressure port, in addition to suction and discharge ports. An economizer heat exchanger is used to enhance hot gas cooling and heating cycles which are initiated by associated electrical or electronic control to achieve and maintain a predetermined temperature range close to a selected set point temperature in a conditioned space.
U.S. Pat. No. 5,174,123, which is assigned to the same assignee as the present application, discloses refrigeration methods and apparatus which utilize a flash tank in a refrigeration unit which has an economizer cycle, in place of an economizer heat exchanger. The disclosed refrigeration arrangement eliminates the need for a float valve in the flash tank, enabling the flash tank to be used in transport refrigeration applications.
A refrigeration unit having an economizer cycle enhances the heating cycle by adding heat to the refrigerant in an economizer heat exchanger, or a flash tank, hereinafter collectively referred to simply as an economizer heat exchanger. This heat may be added to the economizer heat exchanger, for example, by circulating liquid coolant from a liquid cooled compressor prime mover, eg., an internal combustion engine, in heat exchange relation with the refrigerant in the economizer heat exchanger. During such a heating cycle hot gas refrigerant from the compressor is discharged into a condensing heat exchanger associated with the conditioned space, and the condensed refrigerant is then evaporated in the economizer heat exchanger while heat is added to the refrigerant from the liquid coolant. We have found that under certain conditions, heat is drawn from the liquid coolant in the economizer heat exchanger so rapidly that the liquid coolant can freeze.
Thus, it would be desirable, and it is an object of the invention, to improve the reliability and efficiency, as well as the control methods and arrangements, of a refrigeration unit in which a refrigerant compressor having discharge, suction and intermediate ports is driven by a liquid cooled internal combustion engine, with the refrigeration unit having an economizer cycle, such as the refrigeration units disclosed in the hereinbefore mentioned patents.
It would be desirable, and it is another object of the invention, to improve the reliability and efficiency of a refrigeration unit having an economizer cycle, during a hot gas heating cycle, notwithstanding start-up of the unit and internal combustion engine during low ambient temperature conditions, which may cause problems associated with freezing of the liquid coolant used to enhance the hot gas heating cycle.

Methods and apparatus for operating a refrigeration unit


A developing apparatus includes a developing roller having a magnet roller for feeding a developer to a photoconductor, and a toner concentration sensor for detecting a toner concentration of the developer, a region of the magnet roller corresponding to a location of the toner concentration sensor, being substantially zero gauss as magnetic flux density distribution.

1. Field of the Invention
The present invention relates to a developing apparatus possessing a magnet roller and having a developing roller for feeding a developer to a photoconductor, and a manufacturing method of a developing roller.
2. Description of the Prior Art
The developing apparatus used in a conventional copier comprises an agitation roller for stirring the developer, a developing roller for feeding the developer to a photoconductor, a feed roller for feeding the developer to the developing roller, an ear cutter or developer height regulator for defining the developer depositing on the developing roller, and a toner concentration sensor. Specifically the developing roller consists of, as shown in FIG. 1, a magnet roller 11, a nonmagnetic sleeve 12 disposed on the surface of the magnet roller 11, and others. This magnet roller 11 possesses plural magnetic poles N1, N2, S1, S2, S3 for feeding the developer to the photoconductor 7. These plural magnetic poles individually adsorb and convey the developer, and form magnetic brushes, which are eared states of the developer, in the area near the photoconductor 7. The magnetic flux density distribution is as shown in the diagram. A toner concentration sensor 10 is disposed above between the magnetic poles S1 and N2 in this magnetic flux density distribution.
The toner concentration sensor 10 is a detector of the toner concentration of the developer passing nearby, and various types are known. For example, incorporating a coil, by detecting the fluctuation of the inductance (L) of the coil by the developer passing nearby, the toner concentration of the developer is detected.
This type of toner concentration sensor 10 is, as a matter of fact, influenced by magnetism. That is, if the toner concentration sensor 10 is present within the magnetic field, an error is caused in the output due to the effect of the magnetic field although the toner concentration is the same.
In the conventional toner concentration sensor 10, as shown in the diagram, the magnetic field in which the toner concentration sensor 10 is present is not zero gauss but possesses a specific magnetic flux density, and therefore the toner concentration output is inaccurate. As a result, the toner concentration is controlled on the basis of this inaccurate toner concentration output, and copies of poor picture quality are made.
Meanwhile, as mentioned above, the magnetic flux density distribution is as shown in FIG. 2, and when the ear cutter or developer height regulator 8 for cutting the ear of the developer is disposed between the magnetic poles S1 and N2 in the magnetic flux density distribution, the developer on the surface of the sleeve 12 of the developing roller 6 beneath the developer height regulator 8 is in an eared state because this location is not zero gauss but possesses a specific magnetic flux density. Supposing the humidity or the toner density varies, a difference is caused in the amount of earning of the developer. Therefore, the earning state of the developer is unstable, and the amount of the developer cut off by the developer height regulator 8 and supplied into the photoconductor is not constant. Hence, the quantity of the toner supplied on the photoconductor 7 is not constant.
Moreover since the magnetic poles involve fluctuations as manufacturing errors, the magnetic flux density may be much higher in a region beneath the developer height regulator 8. In this case, the developer ears up higher, and the cutting amount by the developer height regulator 8 differs greatly every time, and the toner quantity supplied on the photoconductor 7 becomes more and more unstable.

Developing apparatus and manufacturing method of developing roller


7-ethyl camptothecin (ECPT), an active metabolite of the camptothecin analog CPT-11, is poorly soluble in water. Because of its poor water solubility, ECPT has not been directly administered by parenteral or oral routes in human patients for the purpose of inhibiting the growth of cancer cells. There is also unpredictable interpatient variability in the metabolic production of ECPT from CPT-11 which limits the utility of CPT-11. This invention overcomes these limitations by teaching novel pharmaceutically acceptable lactone stable ECPT formulations for the direct administration of ECPT. The claimed invention also describes novel dosages, schedules, and routes of administration of the lactone stable ECPT formulations to patients with various forms of cancer.

1. Field of the Invention
7-ethyl Camptothecin ("ECPT") is a potent inhibitor of the enzyme Topoisomerase I and has demonstrated broad anticancer activity in a variety of preclinical tumor models. The lactone form of Camptothecin (CPT) is poorly soluble in water and has significant antitumor activity and hydrolysis of E-ring lactone to the carboxylate form of camptothecin greatly increases the water solubility of molecule at the expense of significantly reducing its antitumor activity. A lactone stable form of camptothecin has not been administered by parenteral or oral routes in humans for the purpose of inhibiting the growth of cancer cells. This invention overcomes these limitations and claims novel pharmaceutically acceptable formulations of lactone stable ECPT, methods of administration of lactone stable ECPT, and antitumor compositions comprising solutions of lactone stable ECPT. Additionally, this invention claims novel dosages, schedules of administration, and routes of administration of ECPT formulations to humans with various forms of cancer.
2. Description of the Related Art
Introduction
A. DNA Topoisomerases
Several clinically important anticancer drugs kill tumor cells by affecting DNA topoisomerases. Topoisomerases are essential nuclear enzymes that function in DNA replication and tertiary structural modifications, such as overwinding, underwinding, and catenation, which normally arise during replication, transcription, and perhaps other DNA processes. Two major topoisomerases that are ubiquitous to all eukaryotic cells: (1) Topoisomerase I (topo I) which cleaves single stranded DNA; and (2) Topoisomerase II (topo II) which cleaves double stranded DNA. Topoisomerase I is involved in DNA replication; it relieves the torsional strain introduced ahead of the moving replication fork.
Topoisomerase I purified from human colon carcinoma cells or calf thymus has been shown to be inhibited by (a) camptothecin, (b) a water soluble analog called "CPT-11," and (c) 10-hydroxy 7-ethyl camptothecin (HECPT) which is the proposed active metabolite of CPT-11. CPT-11, camptothecin, and an additional Topo I inhibitor, topotecan, has been in used in clinical trials to treat certain types of human cancer. For the purpose of this invention, camptothecin derivatives include 7-ethyl camptothecin (ECPT), CPT-11, 10-hydroxy 7-ethyl camptothecin (HECPT), 9-amino camptothecin, 10,11 methylenedioxy camptothecin and topotecan. These camptothecin derivatives use the same mechanism to inhibit Topo I; they stabilize the covalent complex of enzyme and strand-cleaved DNA, which is an intermediate in the catalytic mechanism. These compounds have no binding affinity for either isolated DNA or topoisomerase I but do bind with measurable affinity to the enzyme-DNA complex. The stabilization of the topoisomerase I "cleavable complex" by camptothecin, CPT-11, or HECPT is readily reversible.
Although camptothecin and the aforementioned camptothecin derivatives have no effect on topoisomerase II, these camptothecin derivatives stabilize the "cleavable complex" in a manner analogous to the way in which epipodophyllotoxin glycosides and various anthracyclines inhibit topoisomerase II.
Inhibition of topoisomerase I by camptothecin and derivatives induces protein-associated-DNA single-strand breaks. Virtually all of the DNA strand breaks observed in vitro cells treated with camptothecin and derivatives are protein linked. However, an increase in unexplained protein-free breaks can be detected in L1210 cells treated with camptothecin. The compounds appear to produce identical DNA cleavage patterns in end-labeled linear DNA. It has not been demonstrated that camptothecin or active derivatives of camptothecin cleaves DNA in the absence of the topoisomerase I enzyme.
B. Activity of Camptothecin and Derivatives is Cell Cycle Specific
The activity of camptothecin and active camptothecin derivatives is cell cycle specific. The greatest quantitative biochemical effect observed in cells exposed to HECPT is DNA single-strand breaks that occur during the S-phase. Because the S-phase is a relatively short phase of the cell cycle, longer exposure to the drugs results in increased cell killing. Brief exposure of tumor cells to the drugs produces little or no cell killing, and quiescent cells are refractory. These results are likely due to two factors:
(1) The drugs inhibit topoisomerase I reversibly. Although they may produce potentially lethal modifications of the DNA structure during DNA replication, the breaks may be repaired after washout of the drug; and PA1 (2) Cells treated with topo I inhibitors, such as camptothecin, tend to stay in G0 of the cell cycle until the drug is removed and the cleaved DNA is repaired. Inhibitors of these enzymes can affect many aspects of cell metabolism including replication, transcription, recombination, and chromosomal segregation. PA1 (1) direct administration of ECPT allows the clinician to tailor the administration of the active cytoxic species (lactone stable ECPT) to suit the patient's tolerance; PA1 (2) direct administration of ECPT overcomes interpatient variability which may be due to polymorphism of key enzyme(s) in the metabolism of CPT-11 to HECPT; and PA1 (3) clinicians can more consistently optimize the drug dosage and schedule to achieve the maximum tolerated dose of ECPT which is likely to lead to the most beneficial clinical anti-cancer effect. PA1 (1) methods of administering lactone stable ECPT to patients with cancer; PA1 (2) solutions of lactone stable ECPT; PA1 (3) antitumor compositions comprising lactone stable ECPT; PA1 (4) stable formulations of lactone stable ECPT suitable for parenteral administration; PA1 (5) pharmacologic schedules for achieving the maximum tolerated dose with acceptable clinical toxicity observed in standard clinical practice of cancer treatment; PA1 (6) a novel oral formulation of ECPT; and PA1 (7) use of ECPT for the treatment of localized complications of cancer by direct administration via instillation into various body cavities.
C. Lactone Form Stabilizes 7-Ethyl Camptothecin Antitumor Activity and Reduces Water Solubility
Utilizing HPLC and NMR techniques, it has been demonstrated that camptothecin and camptothecin derivatives with native lactone E-ring moieties undergo an alkaline, pH-dependent hydrolysis of the E-ring lactone. The slow reaction kinetics allows one to assess if both the lactone and non-lactone forms of the drug stabilizes the topoisomerase I-cleaved DNA complex. Studies indicate that only the closed lactone form of the drug helps stabilize the cleavable complex. This observation provides reasoning for the high degree of camptothecin activity observed in solid tumor models. Tumor cells, particularly hypoxic cells prevalent in solid neoplasms, have lower intracellular pH levels than normal cells. At pH levels below 7.0, the closed form of camptothecin predominates. Thus, the inventors predict that ECPT will be more effective at inhibiting topoisomerase I in an acidic environment than in cells having higher intracellular pH levels. This invention provides lactone stable ECPT as the basis of the claimed subject matter. For this invention, lactone stable ECPT is defined as ECPT which is dissolved in DMI or DMA in the presence of a pharmaceutically acceptable acid. The presence of the acid stabilizes the lactone form of ECPT. For the purpose of this invention lactone stable ECPT and ECPT are used interchangeably.
D. Camptothecin and Derivatives
In 1966, Wall and Wani isolated camptothecin from the plant, Camptotheca acuminata. In the early 1970's, camptothecin reached Phase I trials and was found to have antitumor activity, but it caused unpredictable myelosuppression and hemorrhagic cystitis. Phase II studies with sodium camptothecin were limited because they induced unpredictable and severe myelosuppression, gastrointestinal toxicity, hemorrhagic cystitis, and alopecia. Clinical trials with sodium camptothecin were eventually discontinued because of unpredictable toxicities.
Because of these limitations and the fact that it is poorly soluble in water, camptothecin has been considered unsuitable for direct clinical use. One aspect of this invention is to formulate ECPT in a pharmaceutically acceptable manner using an organic solvent or a mixture of organic co-solvents to stabilize CPT in the lactone ring form. It is this lactone stable ECPT which permits direct administration of CPT to cancer patients. An additional embodiment of this invention is to provide specific indications, schedules, dosages and routes of administration of lactone stable ECPT for the purpose of treating cancer in humans.
The selection of suitable organic solvents for pharmaceutical dosage forms is limited to those which have a high degree of physiological safety. This invention describes administration of lactone stable ECPT in a pharmaceutically acceptable multi-solvent formulation, overcomes interpatient variability and drug resistance as it relates to the CPT-11 conversion to HECPT and is useful in instances where human cancer cells, because of their altered enzymatic activity, resist metabolic conversion of CPT-11 to HECPT.
Two camptothecin derivatives, CPT-11 and topotecan, have less sporadic toxicities but retain significant activity of the parent compound. CPT-11 and topotecan are currently undergoing Phase I and Phase II development in the United States. 10,11 methylene dioxycamptothecin is reportedly very active in preclinical studies, but it is also reported to be relatively insoluble in water which limits its use in the clinic (Pommier, et al. 1992).
In preclinical studies, Kunimoto and co-workers administered camptothecin at similar dosages (10-100 mg/kg intraperitoneally) to CDF1 mice implanted with intraperitoneal L1210 leukemia and demonstrated superior T/C (treated/control) ratios relative to mice treated in the same manner with 7-ethyl camptothecin (ECPT) and 10-hydroxy 7-ethyl camptothecin (HECPT). Their results with camptothecin, ECPT and HECPT were inferior that of CPT-11 administration under the same conditions. The inventors of the instant invention believe that the lesser activity observed by Kunimoto is related to the lack of an optimized pharmacologic schedule for ECPT. The instant invention takes into account the requirement for administration of the lactone stable species of ECPT by a prolonged, not bolus, parenteral infusion or by the repeated oral, parenteral or topical administration of the drug in a manner which closely replicates the pharmacokinetics of a continuous parenteral infusion.
Tables 1 and 2 present data summarizing Phase I and Phase II clinical trials of CPT-11. Neutropenia and diarrhea are the major reported, dose-limiting toxicities of CPT-11.
TABLE 1 __________________________________________________________________________ PHASE I STUDES CPT-11 Investigator Schedule # Pts Dose Toxicity Tumor Type __________________________________________________________________________ Clavel et al 90 min. 37 pts 115 mg/m.sup.2 /d Neutropenia* diarrhea, Breast (1 PR) QDx 3 Q21 days (33-115) nausea and vomiting, Mesothelioma alopecia (1 PR) Culine et al 90 min. 59 150 mg/m.sup.2 /wk Neutropenia* diarrhea* esophagus (1 PR) Q21 days (50-150) vomiting, alopecia cervix (1 PR) fatigue stomatitis renal (1 PR) Neutropenia* ovarian (1 PR) Negoro et al 30 min 17 100 mg/m.sup.2 Diarrhea*, N/V, NS CLC (2 PRs) infusion (50-150 alopecia, liver dys- function Ohe et al 120 hr CI 36 40 mg/m.sup.2 /d Diarrhea* nausea and None Q3 wks (5-40) vomiting, thrombo- cytopenia, anemia, liver dysfunction Diarrhea* Rothenberg et al 90 mg QWx 4 32 180 mg/m.sup.2 /wk Neutropenia, nausea, Colon Ca (2 PRs) Q42 days (50-180) vomiting, alopecia Rowinsky et al 90 min infusion 32 240 mg/m.sup.2 Neutropenia* vomiting, Colon Ca (1 PR) Q21 day (100-345) diarrhea abd. pain, Cervix Ca (1 PR) flushing __________________________________________________________________________ *Dose Limiting Toxicity
TABLE 2 __________________________________________________________________________ CPT-11 PHASE II TRIALS Investigator Tumor Type Schedule # Pts Response Rate Reported Toxicities __________________________________________________________________________ Fukuoka et al Untreated Non Small 100 mg/m.sup.2 weekday 73 (23/72) PRs Neutropenia diarrhea, Cell Lung Cancer 31.9% nausea, vomiting, anorexia, alopecia Masudu et al Refractory or Relapsed 100 mg/m.sup.2 weekly 16 (7/15) PRs Neutropenia, diarrhea Small Cell Lung Ca 47% pneumonitis (12.5%) Negoro et al Small Cell Lung Cancer 100 mg/m.sup.2 /week 41 2 CRs and 7 Neutropenia (38.6%) PRs 33.3% N/V (61.5%) diarrhea (53.8%) alopecia (40.0%) Ohno et al Leukemia/Lymphoma 200 mg Q3 No resp. 62 ** Neutropenia (91%) 40 mg/m.sup.2 Q0x5 34% PR Thrombocytopenia 20 mg/m.sup.2 bid x7 25% RR Gastrointestina 1 (76%) Shimada et al Colon cancer 100 mg/m.sup.2 /week or 17 6/17 (PR) Neutropenia (53%) 150 mg/m.sup.2 /Q 2 wks 46% NN (35%) diarrhea (24%) Takeuchi et al Cervical cancer 100 mg/m.sup.2 weekly 69 SCR Neutropenia (89%) 150 mg/m.sup.2 weeks 8 PR N/V (51%) RR of 23.6% Diarrhea (39.1%) Alopecia (38.1%) __________________________________________________________________________ **see text
E. HECPT is the Active Metabolite of CPT-11
Preclinical data, obtained by Barilero et al. on animals and more recently on humans, suggest that HECPT is the active metabolite of CPT-11 in vivo. Several different researchers administered CPT-11 and HECPT intravenously during Phase I trials and recorded the peak plasma concentrations (CpMax) at the end of the infusions. An analysis of the published mean peak plasma concentrations indicates that approximately 1.5% to 9% of the administered CPT-11 (on a per/mg basis) is converted into HECPT. The pharmacokinetic data from 30-minute intravenous infusions show a lower percentage of conversion (.about.1.5%) of CPT-11 to HECPT than that observed following more prolonged infusions (.about.9% at 40 mg/m.sup.2 /d.times.5). The reported half life of HECPT observed in humans following the administration of CPT-11 ranges from 8.8 to 39.0 hours.
The biochemical and pharmacological relationship between CPT-11 and HECPT, as well as the role these compounds play in killing cancer cells in vivo is not completely understood. Investigators studying in vitro tumor cell lines have reported that HECPT has a 3600-fold greater inhibitory activity than CPT-11 against topoisomerase I in P388 cells and that HECPT is approximately 1000-fold more potent in generating single-strand DNA breaks in MOLT3 cells (Kawato, et al ( 1991)). However, Kaneda et al. report that HECPT has little anti-tumor activity compared to CPT-11 in vivo. They base their findings on studies conducted using an intermittent bolus schedule (days 1, 5, and 9) and an i.p. route of administration with an intraperitoneal P388 tumor model in mice.
Ohe et al. suggest that HECPT is a more toxic moiety of CPT-11 and could be responsible for much of the toxicity attributed to CPT-11. However, these same investigators noted a lack of correlation between HECPT pharmacokinetics and dose or CPT-11 pharmacokinetics and toxicity in human subjects. Furthermore, Ohe et al. noted a large range of interpatient variability in the AUC of CPT-11 and its metabolism to HECPT, which may result in unpredictable variability in the pharmacokinetic behavior, clinical anti-tumor effects, and toxicity in the individual patient. The data Ohe et al. obtained (using a 5-day, continuous intravenous infusion of CPT-11) also suggests that the conversion of CPT-11 to HECPT is a saturable process. If this is so, the clinical approach to maximizing dose intensity of the active metabolite would impose additional limitations on the effective use of CPT-11.
In preclinical studies of xenografts of human tumors in nude mice, Kawato et al. report that the sensitivity of human tumors to CPT-11 is independent of their ability to produce HECPT and that the effectiveness of CPT-11 is not related to the ability of the tumor to produce HECPT. Kawato et al. suggests that HECPT production is likely to be mediated in the plasma or interstitial compartment. Kaneda et al. observed that the plasma concentration of HECPT in mice was maintained longer after CPT-11 administration than after treatment with HECPT and suggested that clinicians should maintain plasma levels of HECPT to enhance the antitumor activity of CPT-11. The present invention has a useful advantage of not requiring activation by an enzyme in order to form the active species (as with CPT-11) and the additional advantage of being able to directly control the interpatient variability.
One of the advantages of present invention provides clinicians with the ability to directly adjust the plasma levels of ECPT to the point of therapeutic tolerance by controlling the dose and the schedule of administration. The inventors contend that this should lead to a superior ability to achieve better antitumor activity and reduce interpatient variability of the plasma levels of ECPT.
The different observations made in these studies suggest that direct administration of ECPT by parenteral and oral administration could provide significant clinical benefit for the treatment of cancer. However, in the past, ECPT has been considered insufficiently water soluble for clinical use. The claimed invention overcomes the solubility problem by providing lactone stable pharmaceutically acceptable multisolvent formulations of ECPT for parenteral use and also oral ECPT formulations.

Lactone stable formulation of 7-ethyl camptothecin and methods for uses thereof


A drive circuit includes a drive transistor connected at a pair of its main electrodes respectively to a drive output terminal side and a reference voltage source VEE side, an operational amplifier for controlling an output voltage that is output from the drive transistor, a detection transistor for detecting a current that flows through the drive transistor, a first feedback loop for detecting an output voltage at the drive output terminal and feeding back the output voltage to the operational amplifier, and a second feedback loop for detecting an output current of the detection transistor and feeding back the output current to the operational amplifier. The drive transistor and the detection transistor form a mirror circuit.

1. Field of the Invention
The present invention relates to a drive circuit for an emitting device that emits at least light or electrons, such as a light emitting diode, a semiconductor laser, an electroluminescence device, or an electron-emitting device.
2. Description of the Related Art
If an emitting device and a drive circuit are connected to each other by a wiring member such as a flexible wiring board and the emitting device is driven, a voltage drop is caused in a wiring member by resistance in the wiring member and a current flowing through the wiring member and the effective drive voltage actually applied to the emitting device might become lower than the output drive voltage of the drive circuit.
FIG. 8 is a diagram schematically showing a matrix display panel 100 formed by combining surface conduction electron-emitting devices 101 and phosphors (not illustrated).
As resistors that affect the effective drive voltage for the electron-emitting devices 101, wiring resistors Rx on column wiring 102 formed of conductors such as metal and wiring resistors Ry and Ryo on row wiring 103 formed of conductors such as metal can be mentioned. Since currents flows into the row wiring 103 from columns, the wiring resistors Ry and Ryo on the row wiring 103 in a panel 100 become predominant.
A method for compensating the voltage drop caused by the wiring resistors in the panel is disclosed in, for example, Japanese Patent Application Laid-Open (JP-A) No. 2002-221933.
Furthermore, conventionally a large area transistor having a large gate width is used as a switch in an output buffer 106 so as to make the voltage drop caused by on-resistance Ron of the switch in the output buffer 106 in a row drive circuit negligible. Therefore, the occupied area on a chip in the case where the row drive circuit is integrated onto one chip becomes large, and the IC chip becomes expensive.
Therefore, a method using a compensation circuit in which the voltage drop caused by the on-resistance is compensated by using a transistor that is smaller than the conventionally adopted one in the output buffer and feeding back a detected voltage at an output terminal 110 has been studied.
However, even this is not a compensation method that is sufficient for enhancing the precision of the drive. For example, a connection member 105 itself; such as flexible wiring, which connects a row drive circuit to the panel 100, has resistance Rfpc. It is demanded to compensate the voltage drop caused by the connection resistance Rfpc with a relatively simple configuration.
In the above-described compensation circuit in which the voltage drop caused by the on-resistance is compensated by feeding back the detected voltage at the output terminal, the detection terminal must be set on the emitting device side serving as the load as compared with the connection resistance Rfpc. Therefore, extra wiring paths become necessary and the arrangement pitch of conductor patterns of flexible wiring becomes high density, resulting in increased parasitic capacitance and a higher cost.


A fly screen apparatus having a screen with a handle at an end thereof. The handle has opposite ends received respectively within a pair of runners. The runner has a guide and positioning track formed on an inside surface of the runner. An intermediate rest element is formed in an intermediate position on the side of the runner. The handle has a guide piece supporting a tip which is longitudinally mobile. The tip follows the guide and positioning track so as to be located in various positions within the runners.

The aim of this invention is a fly screen with a quick-release mechanism for hooking and unhooking the handle, used particularly for fly screens with a chain operated movement.
The invention has particular, but not necessarily exclusive, application in the sector involved in accessories for fixtures and fittings.
The fly screens which are currently available may be divided into two main categories. The first type is made-to-measure, manufactured according to the dimensions required for a given client, delivered to the client and installed by a specialized installation technician. The other type is sold in kit form, and is the type which is most widely available on the market.
The latter type of fly screen, characterized by the fact that it is reasonably efficient and economic, is the main target area at which this invention is aimed. Large quantities of components have to be fabricated and transported by the manufacturing companies, especially when dealing with overseas markets. The xe2x80x9cdo-it-yourselfxe2x80x9d concept is widely used and offers a product that satisfies most normal requirements, although it is not up to the standards of the made-to-measure type.
Both of the examples mentioned have certain components in common, especially the casing, which is generally made from extruded aluminum bar. It is used to house the co-axial rewind mechanism for the fly screen, roller blind or sun blind, which in the manual version has a corresponding loaded return spring. The ends of the casing are sealed by special plates or headers, which are supplied in two different versions, that is, a fixed type or together with counter-plates or caps that can be regulated.
There are obviously a number of variations, although they are very similar to the systems described, and are just as common in fly screens as in roller blinds and sun blinds. One of these variations, for example, is the lower quality fly screens which do not have the aforementioned return spring inside the mechanism. They differ from the first type in that both the unwinding and rewinding operations of the fly screen are carried out manually. In this case, there is a closed-loop chain that hooks around a cog or pulley fixed on one end of the relative rewind roll, which is housed inside a casing, in order to unwind or rewind the screen in a controlled manner.
These solutions foresee the fabrication of assemblies, for example fly screens, which are basically made up as follows:
a casing which is closed at its ends by corresponding headers;
a rewind roll housed inside the casing, supported at each end by a pair of header plates which are fixed to the ends of the casing;
a helicoidal torsion spring positioned co-axially, and which works in conjunction with the rewind roll;
a rod positioned co-axially to the helicoidal spring;
a piece of material or cloth, either net type or for shading purposes, with one end joined to the rewind roll and the other end joined to a handle; and
two runners, in which the two ends of the handle and the edges of the material or cloth slide.
Especially with the type that has the rewind roll controlled by the closed-loop chain mechanism, certain drawbacks have been encountered. They are due to the fact that the material or cloth is only held tight by the handle, which usually has a counterweight. As a result, this type of assembly has no means which acts upon the handle to counteract pressure exerted on the surface of the material or cloth which may cause it to lift up. In fact, if the material or cloth is subjected to pressure on the surface, due to winds or a part of the body accidentally pushing against it, it is deformed according to the amount of pressure exerted, with the handle being lifted proportionally to the deformation of the material or cloth. This deformation, which is usually random, produces a phenomenon which is known as xe2x80x9csail effectxe2x80x9d.
This so-called xe2x80x9csail effectxe2x80x9d causes certain drawbacks. Firstly, the efficiency of the material or cloth may be compromised because, especially with the cheaper fly screens, the lateral edges tend to come out of the runners to leave openings through which insects may enter or, in the case of sun blinds, light.
Secondly, because of the continuous effect of the wind which blows in various directions, the fly screen may be noisy, an effect that is increased by the sudden rubbing of the components due to the up and down vertical movement and lateral play of the handle inside its relative runners.
In order to overcome these and other drawbacks, and at a considerable cost, some consumers choose fly screens with two battens which slide horizontally rather than vertically. In this case, the material or cloth is unwound by pulling the handle in one direction, and fixing it in position when it reaches its limit with vertically mobile fasteners, the ends of which go inside corresponding seats, usually positioned on the lower runner. Since this type of fly screen has two battens, both purchase price and installation costs are obviously higher. This is because two casings are usually required, each one positioned vertically along the two corresponding sides of the space to be fitted out. On the other hand, a large part of the extra cost for each fitting depends on each individual supplier and on the type of assembly used and which, operating in a different direction compared with traditional methods, requires more complicated manufacturing operations.
A fly screen known as Genius was recently put on the market, which was designed to overcome the aforementioned problems. It is particularly used for horizontal fly screens, with the movement of the rewind roll imposed by manual traction of a closed-loop chain. This type of assembly, used for doors with a large inter-axis, is made up basically of:
a casing containing a rewind roll which is pre-charged by operating in conjunction with at least one torsion spring;
a mesh-type screen which is fastened at one end to the rewind roll, and to a handle at the other end;
runners in which the ends of the handle slide; and
a handle, the ends of which operate in conjunction with holding means located in the lower part of the runners.
The user, when unwinding the screen, pulls the closed-loop chain in one direction to carry out the lowering of the screen, until its respective handle reaches the limit at the base of the opening in question. When this position has been reached, in order to fasten the handle and, therefore, keep the screen in a stretched position, the user must be able to carry out a further pull-so that the handle, made out of a rectangular tubular profile, rotates and inclines slightly on one side. In this position, pieces that protrude from the two ends of the handle intercept dedicated seats formed on the lower side of the runners, forcing the pieces to take up a certain position. At this point, the user releases the closed-loop chain so that the screen, which is under tension, pulls the handle upwards to force it from a slightly rotated position into a vertical position, forcing the pieces into corresponding recesses with stop points.
In order to release the handle and rewind the screen, the assembly has a type of pedal fastened to the handle. The purpose of this pedal, which is located in a central position, is that when it is pressed by the user, it works in conjunction with the movement applied to the closed-loop chain. In particular, the user has to apply a slight pull downward on the chain with one hand in order to move the screen, while pressing the pedal with a foot. The pressure applied in this way on the pedal obliges the handle to rotate on one side, releasing it from its holding point and, since it is now free, it may be rewound due to the elastic pull.
The drawbacks, mentioned in the solutions above, have been satisfactorily resolved in patent application No. ITTV2000A000030 (Bettio). The patent describes a quick-release hooking and unhooking device for the handle, used particularly for fly screens and fly screen assemblies with a chain type movement made with the system, which comprises:
a casing containing a rewind roll which is pre-charged by operating in conjunction with at least one torsion spring;
a mesh-type screen which is fastened at one end to the rewind roll, and to a handle at the other end;
runners in which the ends of the handle slide; and
a handle with a tubular profile, with a hooking means on at least one end which operates in conjunction with a reciprocal holding means, located at the lower end of the corresponding runner; in which, the holding means consists of a block, which is fastened to the lower end of the runner. The block is open on one side and has two surfaces that face each other and which have a mirror-image track with an inlet and an outlet, and an intermediate rest position. The track is hooked by a hooking means located at the end of the handle, and includes a guide piece which is joined to the handle and which longitudinally guides a mobile tip. The tip has a protruding pin on at least one of its sides that fits into at least one of the two tracks in the block.
Although this solution is of considerable value because of its contribution in resolving the problems connected with the pre-existing assemblies, it is still not completely optimized. In fact, following a series of laboratory tests, the applicant for the patent has noticed that the functionality of the stop mechanism of the handle is inconsistent, especially in certain conditions. The malfunction has been noticed when the lowering movement of the screen is carried out very quickly, where the path of the tip in the block is intercepted correctly, but it is also immediately released.
This event happens quite frequently, and is due to the fact that it is difficult to dampen the contact of the tip, which is part of the hooking mechanism joined to the ends of the handle, when the tip, or a part of it, strikes against the lower, inclined portion of the first part of the track. In this case the tip, which is the main moving part on the end of the handle, tends to rebound and, instead of slipping into the recess located between the inlet and outlet part of the track, hits above and overrides it, and ends up in a position which, being free of obstacles, is immediately before the outlet.
The result is that the handle is not hooked at the lower end of the runners, and in some cases may be distant from the base. Under these circumstances, apart from the fact that the screen is not pulled tight, there may be a gap through which insects may enter or, in the case of blinds, light may enter.
In view of the above considerations, therefore, it is imperative to single out an acceptable solution.
This and other aims are achieved through the use of this invention according to the characteristics in the attached claims, solving the problems described by means of a fly screen with a quick-release mechanism for hooking and unhooking the handle, used particularly for fly screens and fly screen assemblies with a chain-operated movement, and which includes:
a casing containing a rewind roll which is pre-charged by operating in conjunction with at least one torsion spring;
a mesh-type screen which is fastened at one end to the rewind roll, and to a handle at the other end;
runners in which the ends of the handle slide;
a handle, in which at least one end has a hooking means and which operates in conjunction with a reciprocal holding means, located at the lower end of the corresponding runner;
at least one holding means at the lower end of the runner, with the upper part which is open and which contains a guide track with an inlet and an outlet, and an intermediate rest position; and
at least one hooking means located at the end of the handle, and which includes a guide piece attached to it, which longitudinally guides a mobile tip. The tip has a protruding pin on at least one side that fits into at least one of the two guide-tracks in the holding means; and in which at the beginning of the guide track, formed in the inlet of the holding means in correspondence with the lower part of at least one runner, there is a deviation towards the lower part which works in conjunction with a stop point.
The aim of this invention, therefore, is to overcome the drawback described in the previous solution, where the mechanism is not hooked correctly when the manoeuver for closing the screen is carried out, and once the handle has been pulled all the way down by the user.
In detail, the presence of the deviator formed by the inlet, and which momentarily interrupts the track which is followed by the tip, allows any excess force operated by the user on the handle to be buffered. Also, there is a vertical stop point located below the opening in order to prevent further unwinding of the handle even when it is pulled too sharply, and which also absorbs the residual forces.
The advantage of this detail, therefore, is that the blocking movement of the handle may be carried out safely and easily, to guarantee that it is always temporarily blocked in position.
The advantage, therefore, is that the screen is always held tightly in position.
These and other advantages will be shown in the following detailed description and drawings of at least one preferred application of the system, which is to be considered merely an illustration and not a limitation.

Fly screen with a quick-release mechanism for hooking and unhooking the handle


A method of microcontact printing comprises (a) providing an elastomeric stamp comprising a printing surface inked with an ink comprising surface-functionalizing molecules, (b) treating the inked printing surface of the stamp with solvent, and (c) contacting the treated inked printing surface of the stamp to a surface of a substrate. The printing surface of the stamp comprises a first relief pattern, or the surface of the substrate comprises a second relief pattern, or both of the surfaces comprise the relief patterns, and a pattern of surface-functionalizing molecules is transferred to the substrate according to one or both of the relief patterns.

Microcontact printing is a printing technique that can be used, for example, to generate patterns of functionalizing molecules (that is, molecules that attach to a substrate surface or coated substrate surface via a chemical bond) to form a patterned self-assembled monolayer (SAM) (that is, a single layer of molecules that are attached, for example, by a chemical bond to a surface and that have adopted a preferred orientation with respect to that surface and even with respect to each other).
A basic method for microcontact printing SAMs involves applying an ink containing functionalizing molecules to a relief-patterned elastomeric stamp (for example, a poly(dimethylsiloxane) (PDMS) stamp) and then contacting the inked stamp to a substrate surface, usually a metal or metal oxide surface, so that SAMs form in the regions of contact between the stamp and the substrate. Alternatively, the elastomeric stamp can be flat (that is, not containing a relief pattern) and the substrate surface can be relief-patterned.
Micropatterned organic and inorganic materials printed using microcontact printing methods can potentially provide unique electrical, optical, and/or biological properties to substrates such as metallized polymeric films. It has proven difficult, however, to obtain good (that is, complete and even) functionalizing molecule coverage using known microcontact printing methods continuously, repeatedly, and/or at high rates.

Solvent assisted method of microcontact printing


Example implementations relate to read operation redirect. For example, a system according in the present disclosure may include a data storage device accessible by a host. The system may include an input/output filter of an operating system of the host. The input/output filter may monitor read operations and write operations from the host to the data storage device. The input/output filter may copy a portion of the data storage device to a random-access memory (RAM) buffer within the host responsive to monitored read operations to the portion exceeding a threshold. The input/output filter may redirect a successive read operation, addressed to the portion of the data storage device, to the copy of the portion in the RAM buffer.

A data storage device may include a solid-state drive (SSD). An SSD may include a solid-state storage device that utilizes integrated circuitry assemblies as memory to store data persistently. A host device may include a computing device supported by an operating system. Commands to the SSD may be communicated from the host. For example, a command from a host to the SSD may request a read operation and/or a write operation to an address in the SSD. Reading and/or writing to a flash memory cell of an SSD may affect the stored charge on the cell and/or on adjacent cells

Hewlett-Packard Development Company, L.P.


The forms hosting system allows a developer to design custom Outlook form regions containing standard and custom managed controls using popular development tools. The forms hosting system provides a runtime wrapper that appears to Outlook as a normal ActiveX control. When Outlook invokes the runtime wrapper control, the runtime wrapper control loads the managed controls defined by the developer. The runtime wrapper control translates messages received from Outlook into messages understood by the managed controls.

Developers of many application programs ("applications") implement the applications so that they can be customized by third parties. To customize an application, a third party develops custom code (e.g., add-ins and document-level customizations) that uses functionality exposed by the application. The custom code may improve the usability of the applications or provide additional functionality (e.g., domain-specific functionality). Such applications are referred to as "host applications" because the custom code is hosted within the process of the application. Developers of applications typically want to encourage the development of custom code for their applications to increase the demand for their applications. As a result, such developers may provide "runtimes" that facilitate the development of custom code. A runtime is code that is loaded along with custom code and provides services to the custom code. These services may include higher-level functionality than exposed by the application or may include domain-specific functionality. When an application is to load and start the execution of custom code, the application may load the runtime and direct the runtime to load and start the execution of the custom code.
Because of the ease of developing custom code as "managed code," many applications support the execution of custom code in the .NET Framework provided by Microsoft Corporation. The .NET Framework provides a common language runtime ("CLR") that provides high-level operating system type services to the managed programs (including custom code and applications) and serves as an execution engine for managed programs. The CLR ensures that managed programs do not take any unauthorized action. As such, the CLR acts as a "sandbox" within which managed programs execute. The CLR provides application domains ("appdomains") in which different managed programs can execute to help ensure that an errant managed program will not unduly affect the execution of another managed program.
Forms allow developers to create new types of email messages to add to the existing mail, calendar, note, and other types of email messages built into an email application. Forms may include user interface elements, such as buttons, text boxes, and so forth, as well as executable code that define the behavior of the form, such as what actions to take when a user clicks a button. Microsoft Office Outlook 2007 introduced a new form technology called form regions. Form regions overcome the limitations of customizing Outlook forms by using form pages in a variety of new ways. For example, form regions can be displayed in the Reading Pane, and can be added to standard forms without creating a derived message class. The older forms framework only allowed executable code to be provided through a scripting language. The new form regions allow developers to write code for a form using managed code (e.g., using .NET) or other Component Object Model (COM)-based languages. In previous versions of Outlook, third parties who wanted to extend the Outlook user interface (UI) to include custom functionality were restricted by limited support for custom forms in Outlook. Often, when you wanted to add a few fields or make a small modification to the form, Outlook required you to redesign the entire form.
In Outlook 2007, form regions allow more ways to add UI to standard forms and simplify the process of designing custom UI. For example, through an adjoining form region, a developer can extend any existing form with additional fields or controls. These adjoining form regions are displayed at the bottom of the first page of a form, and each adjoining form region is collapsible. Developers can also add a separate form region, which is displayed as a full additional form page and can appear on any existing standard form or custom form. Another benefit of using form regions is that form regions support visual themes. In the past, developers were required to use custom Microsoft ActiveX controls or advanced workarounds to enable a themed look to custom forms. With form regions, all of the controls that come with Outlook 2007 inherit the Microsoft Windows theme.
Although popular development tools, such as Microsoft Visual Studio 2005, provide support for developing Office add-ins, these tools are missing some key components that are useful for writing Outlook 2007 COM add-ins in managed code, and in particular Outlook form regions. Although using Microsoft Visual Studio Tools for the Microsoft Office System (VSTO) would be the preferred development approach for writing Outlook form region controls, VSTO is currently incompatible with Office 2007 applications. In addition, these development tools do not have a comprehensive awareness of the interfaces and other points of contact between the forms hosting environment provided by Outlook and the controls written by developers. Therefore, developers must either write traditional ActiveX controls and forego the conveniences of the managed environment, or write newer managed controls and invest substantial extra effort to manually describe the interfaces needed to communicate with Outlook. The lack of understanding of the forms region architecture by popular development tools adds additional difficulty for the developer in all stages of the development process, including design, development, and debugging. These difficulties increase the amount of time spent by the developer overcoming hurdles of the environment and decrease the time available to the developer to spend on improving her component.


The invention relates to an electrodipping device comprising, in a known manner, a bath of enamel, and a transport device used, during the continuous method, to dip the workpieces to be coated into the bath of enamel, to move the workpieces through the bath, and remove the same therefrom. Electrodes are arranged in the bath of enamel, along the path of displacement of the workpieces, said electrodes being connected to a voltage source with one pole thereof. The second pole of said voltage source is connected to a contact rail extending along the path of displacement of the workpieces. Each workpiece is provided with a contact device which is in contact with the contact rail. A controllable voltage regulating unit is arranged between each contact device and the corresponding workpiece. A position determination device enables the momentaneous position of each workpiece to be determined. A control system is used to apply a control signal to the corresponding voltage regulating unit in such a way as to maintain each workpiece at a desired voltage in each position of the course thereof through the bath of enamel.

In electro-dip lacquering, also termed electrophoretic lacquering, the lacquer components in the lacquer bath are deposited on the workpieces under the influence of an electric field. It has proved advisable not to keep the electric field constant during the passage of the workpieces through the lacquer bath, but to vary it along the movement path, in particular to let it increase with the distance covered. A reason for this measure inter alia is that the lacquer coating building up represents an electrical resistance, which makes the further build-up of the lacquer coating difficult.
The problem thus arises of how the voltage can be changed for each workpiece as it passes through the lacquer bath. In electro-dip lacquering devices of the type named at the beginning, such as described for example in DE 199 42 556 C2, the current is supplied to the workpiece via a contact rail divided into individual sections in the movement direction of the workpieces to be lacquered; the sections are galvanically separated and connected to one pole of a voltage source assigned to each section. The electrodes arranged along the movement path of the workpieces in the lacquer bath are connected to the other pole of the voltage source. It is disadvantageous in this case that it is relatively difficult to track the path of each individual workpiece along the various sections of the contact rail in control terms and to effect the transition of the workpiece from one section to another section without "jump" in potential. Since the charge flowing between electrode and workpiece is used as a measure for the coating thickness applied, it is necessary to "activate" the measurement of the current flowing to the workpiece section-wise too with the movement of the workpiece. After all, the "cuts" in the contact rails which cause the galvanic separation also represent unevennesses in the contact rail which lead to wear of the contact devices that are moved together with the workpieces.
In the event of changes in the workpiece, e.g. in the length of the workpiece, or in the event of a change in the dipping curve, the positions of the cuts between the contact rail sections change, so that an installation change is necessary for an optimum coating.
The present invention is directed to resolving these and other matters.