description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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This invention is a Continuation-In-Part of Ser. No. 09/273,446, “Reliable, Modular, Production Quality Narrow-Band High Rep Rate F 2 Excimer Laser”, filed Mar. 19, 1999. This invention relates to pulse power systems for gas discharge lasers.
BACKGROUND OF THE INVENTION
Pulse Power Systems
Pulse power electrical systems are well known. One such system is described in U.S. Pat. No. 5,142,166 issued to Birx. That patent described a magnetic pulse compression circuit which shortens and amplifies an electrical pulse resulting from the discharge of a charge storing capacitor bank. The patent also describes a induction transformer for amplifying the pulse voltage.
Another pulse power circuit is described in U.S. Pat. No. 5,729,562 issued to Birx, et al. which describes a pulse power system for a gas discharge laser and includes an energy recovery circuit for recovering electrical energy reflected from the laser electrodes.
Gas Discharge Lithography Lasers
Gas discharge lasers are well known and many of these lasers utilize pulse power systems such as those described in the two above-referenced patents to provide short high-voltage electrical pulses across the electrodes of the lasers. One such gas discharge laser is described in U.S. Pat. No. 4,959,840.
Lasers similar to the one described in U.S. Pat. No. 4,959,840 utilizing pulse power systems like the one described in U.S. Pat. No. 5,729,562 are utilized as light sources for integrated circuit lithography. At the present time, most of these lasers are configured to operate as KrF lasers utilizing a laser gas comprised of about 0.1 percent fluorine, about 1.0 percent krypton and the rest neon. These lasers produce light at a wavelength of about 248 nm.
There is a need for lithography light sources at wavelengths shorter than 248 nm such as that produced when the lasers are configured to operate as ArF or F 2 gas discharge lasers which produce laser beams with wavelengths of about 193 nm and about 157 nm, respectively. In the case of the ArF laser the gas mixture is substantially argon, fluorine and neon and in the case of the F 2 laser the gas mixture is substantially F 2 and He or F 2 and neon.
Optical Damage
Fused silica is the primary refractive optical material used in integrated circuit lithography devices. At wavelengths in the range of 193 nm and 157 nm fused silica is damaged by high intensity ultraviolet radiation. The damage is caused primarily by double photon excitation so that for a given pulse energy, the extent of the damage is determined largely by the shape and duration of the pulse.
Modular Pulse Power System
An electrical drawing of a prior art modular pulse power system is shown in FIG. 1 . In a prior art system the components of the pulse power system are provided in a power supply module, a commutator module and a unit called the compression head which is mounted on the laser chamber.
High Voltage Power Supply Module
High voltage power supply module 20 comprises a 300-volt rectifier 22 for converting 208-volt three phase plant power from source 10 to 300-volt DC. Inverter 24 converts the output of rectifier 22 to high frequency 300 volt pulses in the range 1000 kHz to 2000 kHz. The frequency and the on period of inverter 24 are controlled by a HV power supply control board (not shown) in order to provide course regulation of the ultimate output pulse energy of the system. The output of inverter 24 is stepped up to about 1200 volts in step-up transformer 26 . The output of transformer 26 is converted to 1200 volts DC by rectifier 28 which includes a standard bridge rectifier circuit 30 and a filter capacitor 32 . DC electrical energy from circuit 30 charges 8.1 μF C o charging capacitor 42 in commutator module 40 as directed by the HV power supply control board which controls the operation of inverter 24 . Set points within HV power supply control board are set by a laser system control board in a feedback system in order to provide desired laser pulse energy and dose energy (i.e., the total energy in a burst of pulses) control.
The electrical circuits in commutator 40 and compression head 60 merely serve to utilize the electrical energy stored on charging capacitor 42 by power supply module 20 to form at the rate of (for example) 2,000 times per second electrical pulses, to amplify the pulse voltage and to compress in time the duration of each pulse. As an example of this control, the power supply may be directed to charge charging capacitor 42 to precisely 700 volts which during the charging cycle is isolated from the down stream circuits by solid state switch 46 . The electrical circuits in commutator 40 and compression head 60 will upon the closure of switch 46 very quickly and automatically convert the electrical energy stored on capacitor 42 into the precise electrical discharge pulse across electrodes 83 and 84 needed to provide the next laser pulse at the precise energy needed as determined by a computer processor in the laser system.
Commutator Module
Commutator module 40 comprises C o charging capacitor 42 , which in this embodiment is a bank of capacitors connected in parallel to provide a total capacitance of 8.1 μF. Voltage divider 44 provides a feedback voltage signal to the RV power supply control board 21 which is used by control board 21 to limit the charging of capacitor 42 to the voltage (called the “control voltage”) which when formed into an electrical pulse and compressed and amplified in commutator 40 and further compressed in compression head 60 will produce the desired discharge voltage on peaking capacitor 82 and across electrodes 83 and 84 .
In this embodiment (designed to provide electrical pulses in the range of about 3 Joules and 16,000 volts at a pulse rate of 1000 Hz to 2000 Hz, about 100 microseconds are required for power supply 20 to charge the charging capacitor 42 to 800 volts. Therefore, charging capacitor 42 is fully charged and stable at the desired voltage when a signal from commutator control board 41 closes solid state switch 44 which initiates the very fast step of converting the 3 Joules of electrical energy stored on charging capacitor C o into a 16,000 volt discharge across electrodes 83 and 84 . For this embodiment, solid state switch 46 is a IGBT switch, although other switch technologies such as SCRS, GTOs, MCTs, etc. could also be used. A 600 nH charging inductor 48 is in series with solid state switch 46 to temporarily limit the current through switch 46 while it closes to discharge the C o charging capacitor 42 .
The first stage of high voltage pulse power production is the pulse generation stage. To generate the pulse the charge on charging capacitor 42 is switched onto C 1 8.5 μF capacitor 52 in about 5 μs by closing IGBT switch 46 .
A saturable inductor 54 initially holds off the voltage stored on capacitor 52 and then becomes saturated allowing the transfer of charge from capacitor 52 through 1:23 step up pulse transformer 56 to C p−1 capacitor 62 in a transfer time period of about 550 ns for a first stage of compression.
Pulse transformer 50 is similar to the pulse transformer described in U.S. Pat. Nos. 5,448,580 and 5,313,481; however, this prior art embodiment has only a single turn in the secondary and 23 separate primary windings to provide 1to 23 amplification. Pulse transformer 50 is extremely efficient transforming a 700 volt 17,500 ampere 550 ns pulse rate into a 16,100 volt, 760 ampere 550 ns pulse which is stored very temporarily on C p−1 capacitor bank 62 in compression head module 60 .
Compression Head Module
Compression head module 60 further compresses the pulse.
An L p−1 saturable inductor 64 (with about 125 nH saturated inductance) holds off the voltage on 16.5 nF C p−1 capacitor bank 62 for approximately 550 ns then allows the charge on C p−1 to flow (in about 100 ns) onto 16.5 nF Cp peaking capacitor 82 located on the top of laser chamber 80 and is electrically connected in parallel with electrodes 83 and 84 and preionizer 56 A. This transformation of a 550 ns long pulse into a 100 ns long pulse to charge Cp peaking capacitor 82 makes up the second and last stage of compression.
Laser Chamber
About 100 ns after the charge begins flowing onto peaking capacitor 82 mounted on top of and as a part of the laser chamber module 80 , the voltage on peaking capacitor 82 has reached about 14,000 volts and discharge between the electrodes begins. The discharge lasts about 50 ns during which time lasing occurs within the optical resonance chamber of the excimer laser. The optical resonance chamber described is defined by a line narrowing package comprised in this example of a 3-prism beam expander, a tuning mirror and an echelle grating and an output coupler.
Prior Art Pulse Shape and T is
A typical pulse shape (power vs. time) of a prior art ArF laser with a pulse power system as shown in FIG. 1 is shown in FIG. 2 . In this example the power rises fast from zero to a first peak in about 5 ns, fluctuates for about 20 ns then decreases to almost zero in about 10 ns. The total energy in the pulse is about 10 mJ. In order to minimize two-photon reactions, without reducing pulse energy, peaks should be reduced and the duration of the pulse should be lengthened. A parameter which is utilized in the lithography industry to evaluate the potential of these pulses to cause optical damage is called the “integral square pulse duration” and its symbol is T is . T is is defined as follows: T is = ∫ ( P ( t ) t ) 2 ∫ P 2 ( t ) t
where P=power
T is for the pulse shown in FIG. 2 is about 35 ns.
The optical pulse duration of the laser is determined by the discharge current duration and by the discharge stability time, which is a function of the fluorine concentration. The current durations of a standard laser is given by:
τ=π• {square root over (LC)}
L laser head inductance, C peaking capacitance
Any change in L or C is not very effective since pulse duration only increases to the square root. In the interest of laser efficiency, the laser head inductance L cannot be increased. Increasing the capacitance C slows down the voltage risetime and significantly increases the amount of energy deposited into the discharge. Both measures deteriorate the discharge quality and efficiency. Therefore a doubling of the pulse duration will not be possible with a simple LC circuit.
Long pulse duration excimers lasers have been built using so-called spiker-sustainer excitation. In this scheme the tasks of reaching gas break-down and sustaining a stable discharge have been divided into two separate systems. Gas break down requires high voltages but only low energies, which is handled by a spiker circuit. A sustainer circuit is matched to the much lower steady state discharge voltage and provides the pumping of the laser. Because the voltage of the sustainer is much lower, a larger capacitance can be used and much longer pulse duration are achievable. In XeCl laser pulse durations up to 1.5 ns have been realized using spiker-sustainer excitation.
Unfortunately, spiker-sustainer circuits are not applicable to lithography lasers. KrF and ArF discharges use F 2 as the halogen donor, which makes discharges inherently more unstable and limits the pulse duration with respect to chlorine based lasers. More importantly, spiker-sustainer excitation provides low gain due to the stretched out power deposition. Lithography lasers require line-narrowing provisions that typically introduce high cavity losses. In such a configuration, the low gain can barely overcome the losses and low laser performance results.
What is needed is a pulse power system for lithography lasers which will provide a substantial increase in T is from about 30-35 ns to about 50-60 ns.
SUMMARY OF THE INVENTION
The present invention provides a long pulse pulse power system for gas discharge lasers. The system includes a sustainer capacitor for accepting a charge from a high voltage pulse power source. A peaking capacitor with a capacitance value of less than half the sustainer capacitance provides the high voltage for the laser discharge.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a drawing showing the electrical components of a prior art pulse power system.
FIG. 2 is a chart showing a prior art waveform.
FIG. 3 is a drawing showing a preferred embodiment of the present invention.
FIG. 4 is a drawing showing the components of a prior art system replaced by the components of FIG. 3 .
FIG. 5 shows the waveform of the present invention.
FIG. 6 shows a family of waveforms at a variety of charging voltages.
FIG. 7 shows the variation of T is with charging voltage.
FIG. 8 shows the variation of pulse energy with charging voltage.
FIG. 9A a prior art configuration.
FIGS. 10A and 10B show components of the present invention.
FIG. 11 shows waveforms of the voltage potential on three capacitors of the FIGS. 10A and 10B embodiment and the laser power waveform.
FIGS. 12A and 12B show a “poor man's” spiker sustainer circuit.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
First Preferred Embodiment
A first preferred embodiment of the present invention can be described by reference to FIG. 3 . This embodiment is exactly the same as the system described in FIG. 1 through pulse transformer 56 . The improvements of the present invention can be described by comparing FIG. 3 to FIG. 2 which shows the main components of the prior art pulse power system of FIG. 1 which are downstream of the pulse transformer.
In this embodiment, long pulses are generated by means of a double pulse excitation circuit. The individual pulses have high gain to allow line-narrowing and are timed in close succession to act as a single pulse. The basic circuit is a variation of the spiker-sustainer circuit. However, the energy stored in the spiker circuit is increased sufficiently to generate a spiker lasing pulse. The second pulse is generated by the sustainer circuit, with a time constant reduced to provide higher gain relative to classical sustainer circuits. The circuits are balanced to provide roughly equal energy in both pulses, which also maximizes the integral square value τ is for the pulse. In the presented implementation, the spiker and sustainer circuits are not independent systems but are closely coupled. This greatly reduces system complexity and eliminates the need to synchronize the two systems.
The sustainer capacitor C p−1 with a capacitance of 27 nF is pulse−charged in about 120 ns through feeder saturable inductor LP-2 from feeder capacitor C p−2 at 24 nF. During this time the spiker or peaking capacitor C p is isolated by the saturable inductor L p−1 . At the end of C p−1 charging, inductor L p−1 changes to a low inductance state and capacitor C p at 8 nF is being resonantly charged. Because C p is much smaller than C p−1 the voltage on C p will ring up to a higher value. The maximum voltage gain can reach a factor of two and is given by: V C p = 2 1 + C p C p - 1 - V C p1
but in the embodiment V Cp =1.5 V Cp−1 .
In this way it is possible to generate a high spiker voltage without the need for separate high and medium voltage systems. In addition the small value of C p results in a fast voltage risetime, which aids in the initiation of stable discharge.
The high voltage on C p will break down the laser gas and generate the first laser pulse. Once C p is depleted the discharge current will be sustained by C p−1 and a second laser pulse is generated. In a properly adjusted system the energy on C p and C p−1 at the instant of gas break down will be roughly equal, to ensure laser pulses of equal size.
The temporal shape of a line-narrowed ArF laser pulse of 10 mJ energy is displayed in FIG. 5 . Also indicated is the integral square duration for this pulse. These curves can be compared with the corresponding prior art curves shown in FIG. 2 . During the life of a lithography laser chamber, the laser will be operated at a large range of charging voltages. It is important that the minimum pulse duration can be maintained over the entire operating range. The pulse shape and the corresponding integral square durations for charging voltages ranging from 850V to 1100V is shown in FIGS. 6 and 7, respectively. The pulse shapes are a function of charging voltage, but the integral square duration is largely unaffected and maintains a value larger than 50 ns.
The pulse energy as a function of charging voltage is displayed in FIG. 8 . There is a direct relationship with minimum roll-off between pulse energy and voltage. This is important for energy algorithms to work properly and to maintain a stable energy dose for wafer exposure. The maximum energy is 14 mJ which provides sufficient lifetime overhead for a nominal 5 mJ laser.
FIG. 11 shows voltage traces of the charges on C p−2 , C p−1 and C p along with a trace of the pulse power. As shown in the laser power trace, the two peaks of the pulse are almost equal.
Physical modifications to the prior art pulse power system downstream of pulse transformer 56 can be described by comparing FIGS. 9A, 9 B, 10 A and 10 B.
FIGS. 9A and 9B show the prior art arrangement. These drawings show C p−1 16 nF capacitor bank, L p−1 saturable inductor which in this embodiment has a saturated inductance of 150 nH, and C p 16 nF capacitor bank. FIG. 9B also shows cathode 6 A and anode 6 B which is connected to ground. Ground structures and high voltage HV buses are also indicated.
FIGS. 10A and 10B show the modifications to provide the first embodiment of the present invention. In this embodiment L p−2 is equivalent to L p−1 in the FIGS. 9A and 9B system C p−2 is arranged in a similar fashion to C p−1 in the FIGS. 9A and 9B system. The additional capacitor bank C p−1 and the additional saturable inductor L p−1 are sandwiched in as shown in the figures. High voltage buses and ground structures are indicated as are electrodes 6 A and 6 B.
While the present invention has been described in the content of a specific embodiment, persons skilled in the laser art will recognize many variations which are possible. For example, capacitor C p−2 and inductor L p−2 shown in FIG. 3 could be eliminated which would make the system less costly but there would be more leakage current and the circuit designed has less control over the resulting waveforms.
Applicants call this circuit the Poor Man's Spiker Sustainer Circuit. The circuit and an example of the waveform are shown in FIGS. 12A and 12B. Therefore, the reader should understand that the scope of the invention is to be determined by the appended claims and their legal equivalents. | A long pulse power system for gas discharge lasers. The system includes a sustainer capacitor for accepting a charge from a high voltage pulse power source. A peaking capacitor with a capacitance value of less than half the sustainer capacitance provides the high voltage for the laser discharge. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Application No. 60/687,781, filed Jun. 6, 2005, entitled TELESCOPING LANDING GEAR, which is hereby incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
The present invention relates to a no-lube telescoping, or sliding, landing gear utilizing high strength synthetic, or natural fiber ribbons or strands as support for extending or lifting an apparatus.
Landing gears are generally designed to have a gear system that motivates a landing portion to the ground thereby supporting an apparatus such as a trailer. Oftentimes these landing systems require frequent maintenance, including the addition of lubricants, to function properly. Additionally, to support high-weight loads, strong, heavy gearing mechanisms are required.
Thus, a landing gear that is lighter and stronger and functions properly without a lubricant is desired.
These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, and appended drawings.
SUMMARY OF THE INVENTION
One aspect of the present invention relates to a landing gear assembly that comprises a first leg member adapted to couple to a vehicle frame member, and a second leg member operably coupled to the first leg member and moveable between a raised storage position and a lowered-in use position. The landing gear assembly further comprises a flexible member operably coupled with the drive mechanism and the second leg, such that the drive mechanism extends the flexible member and moves the second leg from the storage position to the in-use position, and wherein the flexible member is adapted to support a weight exerted on the first and second leg members.
Another aspect of the present invention is a vehicle frame assembly that comprises a vehicle frame, and a landing gear assembly. The landing gear assembly comprises a first leg member adapted to couple to a vehicle frame member, and a second leg member telescopingly coupled to the first leg member and moveable between a raised storage position and a lowered in-use position. The landing gear assembly also comprises a winch assembly including a first pulley, and a transit pulley operably coupled to the first leg member. The landing gear assembly further comprises a flexible member operably coupled with the drive mechanism and the second leg, wherein the flexible member extends from the first pulley, about the transit pulley, and is fixedly coupled to the second leg member, the drive mechanism extending the flexible member and moving the second leg member from the storage position to the in-use position, and wherein the flexible member is adapted to support a weight exerted on the first and second legs.
Due to the heavy weight and cumbersome nature of standard landing gears, a significant weight advantage is achieved by replacing traditional threaded rod and gear mechanisms with pulleys/rollers and fibers. The present invention provides a landing gear having fibers that are of high tensile strength and withstand fatigue and elongation. Furthermore, the fibers are resistant to heat, chemicals, and degradation without compromising excellent flexibility that is better than steel cable. Moreover, the present inventive landing gear includes an uncomplicated design, can be operated by even unskilled workers, is efficient in use, capable of a long operating life, and is particularly well adapted for the proposed use.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of a semi-trailer unhitched from an associated truck tractor, and having a landing gear thereon supporting a front end of the semi-trailer;
FIG. 2 is a cross-sectional front side elevation view of the landing gear taken along the line II-II, FIG. 1 ;
FIG. 3 is a top cross-sectional view of the landing gear taken along the line III-III, FIG. 2 ;
FIG. 4 is a front cross-sectional view of the landing gear taken along the IV-IV, FIG. 3 ; and
FIG. 5 is a perspective view of an alternative landing gear assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in FIG. 1 . However, it is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.
The reference numeral 10 ( FIG. 1 ) generally designates a landing gear assembly embodying the present invention. In the illustrated example, the landing gear assembly 10 supports a forward end of a semi-trailer 12 . The landing gear 10 typically includes a pair of leg assemblies spaced across a width of the trailer 12 and located near respective front corners of the trailer 12 . The landing gear assembly 10 is capable of extending to engage a ground surface 14 or other supporting surface to hold up the front end of the semi-trailer 12 as is well understood in the art. A shoe 16 of the landing gear assembly 10 is pivotally mounted on a lower portion thereof for engaging the ground surface 14 . The landing gear assembly 10 is also capable of retracting to an up and out of the way position or a storage position when the semi-trailer 12 is being pulled over the road by a tractor (not shown). A crank handle 18 is used to adjust the landing gear assembly 10 between the raised storage position and the lowered in-use position, as described below. The following description is confined to the landing gear assembly 10 as illustrated in FIG. 1 , however, it is noted that the landing gear assembly (not shown) associated and supporting an opposite side of the semi-trailer 12 is constructed and coupled to the trailer 12 in a similar manner. Such constructions are well understood by those of ordinary skill in the art and will not be further described herein.
The landing gear assembly 10 comprises a first leg member 20 fixedly coupled at a first end 22 to a vehicle frame member 24 , and a second leg member 26 having an interior space 28 telescopingly receiving the first leg member 20 therein. A winch assembly 30 is connected to the first end 22 of the first leg member 20 and is operably coupled to the second leg member 26 by a flexible ribbon 32 , as is described below. The winch assembly 30 is driven by a drive mechanism 34 that includes the crank handle 18 .
The first leg member 20 ( FIG. 3 ) includes a mounting plate portion 36 including a plurality of mounting apertures 38 that receive bolts 40 therein mounting the first leg member 28 to the vehicle frame member 24 . The first leg member 20 also includes a T-shaped slide portion 42 that telescopingly engages the second leg member 26 , as described below. The first leg member 20 further includes a pair of guide portions 44 spaced outside the slide portion 42 that guide the second leg member 26 when telescoping between the raised and lowered positions, as described below.
The second leg member 26 comprises a C-shaped, cross-sectional configuration including tab portions 46 that engage with the T-shaped slide portion 42 of the first leg member 20 , thereby telescopingly coupling the first leg member 20 and the second leg member 26 . The first leg member 20 and the second leg member 26 cooperate to form an interior space 48 within which the winch assembly 30 is located. The second leg member 26 further includes a longitudinally-extending pocket 50 that serves to reduce the overall weight of the landing gear assembly 10 .
The winch assembly 30 ( FIG. 4 ) includes a first pulley 52 operably connected to the second leg member 26 by the flexible ribbon 32 , and to the drive mechanism 34 by a gear train 54 . The drive mechanism 34 includes the manual crank handle 18 fixedly connected to an input or drive shaft 56 that is shiftable between a first position providing a first drive speed, and a second position providing a second drive speed, as described in detail in U.S. patent application Ser. No. 11/412,688, filed on Apr. 27, 2006, entitled L ANDING G EAR AND M ETHOD OF A SSEMBLY , which is a divisional of U.S. application Ser. No. 10/405,079, filed on Apr. 1, 2003, entitled L ANDING G EAR AND M ETHOD OF A SSEMBLY , each of which is incorporated by reference herein in the entirety. A first input gear 58 and a second input gear 60 are fixed about the drive shaft 56 . A first output gear 62 and a second output gear 64 are fixedly coupled to an output shaft 66 , and are engagable with the first input gear 58 and the second input gear 60 when the drive shaft 56 is located in position A and position B, respectively. It is noted that the gearing ratios as provided between the input gears 58 , 60 and the output gears 62 , 64 drive the first pulley 52 at a relatively slower and faster speed when the drive shaft 56 is located in positions A and B, respectively.
As best illustrated in FIG. 2 , the flexible ribbon 32 extends from the first pulley 52 downwardly about a transit pulley 68 that is rotationally coupled to a second end 70 of the first leg member 20 , and upwardly to an end 72 that is fixedly connected to an upper end 74 of the second leg member 26 . In operation, rotating the crank handle 18 in a first direction as represented by reference numeral 76 retracts or wraps the flexible ribbon 32 about the first pulley 52 , thereby shortening the overall effective length of the flexible ribbon 32 and forcing the second leg member 26 downwardly with respect to the first leg member 20 in a direction as represented by directional arrow 78 . A second pulley 80 ( FIG. 4 ) is fixed for rotation with the drive shaft 56 and is coupled to the second leg member 26 by a second flexible ribbon 82 , wherein an end of the second flexible ribbon 82 is fixedly connected to the second leg member 26 . In operation, the second leg member 26 is retracted or moved from the lowered in-use position to the raised storage position by moving the handle 18 in a direction 84 which retracts or wraps the second flexible ribbon 82 about the second pulley 80 , thereby moving the second leg member 26 upwardly in a direction 86 with respect to the first leg member 20 .
The reference numeral 10 a ( FIG. 5 ) generally designates another embodiment of the present invention, utilizing additional pulleys therein to multiply the mechanical force generated. Since the landing gear assembly 10 a is similar to the previously-described landing gear assembly 10 , similar parts appearing in FIGS. 2-4 and FIG. 5 , respectively, are represented by the same, corresponding reference numeral, except for the suffix “a” in the numerals of the latter. In the illustrated example, the second leg member 26 a is telescopingly received within the first leg member 20 a . The flexible ribbon 32 a extends downwardly from the first pulley 52 a of the winch assembly 30 a , about a first transit pulley 68 a pivotally coupled to a distal end 88 of the first leg member 20 a , about a second transit pulley 92 that is pivotally connected to the upper end 74 a of the second leg member 26 a , and is fixedly connected at an end 94 to the distal end 88 of the first leg member 20 . The landing gear assembly 10 a further includes return mechanisms similar to that previously described with respect to the landing gear assembly 10 . In operation, the landing gear assembly 10 operates in a similar manner to that of the landing gear assembly 10 as previously described.
Due to the heavy weight and cumbersome nature of standard landing gears, a significant weight advantage is achieved by replacing traditional threaded rod and gear mechanisms with pulleys/rollers and fibers. The present invention provides a landing gear having fibers that are of high tensile strength and withstand fatigue and elongation. Furthermore, the fibers are resistant to heat, chemicals, and degradation without compromising excellent flexibility that is better than steel cable. Moreover, the present inventive landing gear includes an uncomplicated design, can be operated by even unskilled workers, is efficient in use, capable of a long operating life, and is particularly well adapted for the proposed use.
In the foregoing description, it will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed herein. | A landing gear assembly comprises a first leg member adapted to couple to a vehicle frame member, and a second member operably coupled to the first leg member and moveable between a raised storage position and a lowered in-use position. The landing gear assembly further comprises a flexible member operably coupled with the drive mechanism and the second leg, such that the drive mechanism extends the flexible member and moves the second leg from the storage position to the in-use position, and wherein the flexible member is adapted to support a weight exerted on the first and second legs. In certain embodiments disclosed herein, the flexible member comprises a ribbon constructed of natural fibers. Other embodiments comprise additional pulleys and flexible members adapted to raise the second leg member from the in-use position to the raised storage position. | 1 |
FIELD OF THE INVENTION
This invention relates in general to educational devices and more specifically to educational devices employing charades, and question and answer in a game situation to teach various subject matter especially religious subject matter.
BACKGROUND OF THE INVENTION
Various educational devices have been employed throughout the years to teach particular subject matter. These educational devices consist primarily of charts, tables, flash cards and the like. Such prior art devices mainly provide instruction on a single subject matter area. Although these educational devices provide an adequate treatment of the subject matter, they provide little in the form of amusement.
Educational devices employing game situations having religious themes are known in the art. These educational devices utilize a playing board, game pieces and cards, wherein individual players complete with each other by question and answer testing, having as their object the educating of the player in religious subject matter. Typical of such educational games are those disclosed in U.S. Pat. Nos. 4,121,823 (Educational Device Employing a Game Situation) and 4,934,709 (Memory Game Apparatus and Method of Play).
Another known popular game involving competing playing teams is the game of "Trivial Pursuit" disclosed in U.S. Pat. No. 4,682,956. The "Trivial Pursuit" game utilizes a game board, game pieces, and game cards containing multiple inquiries, each requiring a a specific single answer, and the correct answer to the inquiries. The playing board surface includes a circular playing path containing symbols which serve as indicia to the multiple inquiries on the game cards. The playing path symbols represent different specialized fields of knowledge. A playing team member moves it's game piece to a particular position on the playing path based on the roll of a die. The field of knowledge the playing team is to be tested on is determined by the symbol on which the game piece is located after the move is completed. The playing member of the playing team draws a game card and shows the game card to the opposing team for answer verification. The playing member then reads the question aloud to the other members of the playing team. The playing team has a designated period of time to provide the correct answer to the question. If the playing team provides the correct answer, it is awarded a scoring marker. The object of the game is to be the first team to reach the center of the playing board after collecting the required number of scoring markers.
Those educational devices employing question and answer as the sole means of player interaction lack the necessary animation to sustain interest and provide stimulation to reinforce the repeat use of such devices.
Games involving teams competing with each other in which members of each playing team are required to present certain game details to the playing team are well known in the art. One such example of a game of this type is known as "Charades". Accordingly in the game of "Charades", before the actual play begins, familiar sayings, quotes and the like are placed on individual slips of paper which are then folded and collected into a central area. Each playing team, in turn, designates a team presenter. When a particular playing team's turn arrives, the designated presenting player draws one of the folded slips from the central area. The presenting player, according to the rules which restrict audible communication with the other team players, must silently convey to the other members of the playing team the saying, quote or the like contained on the slip.
Another game known in the art which involves competing playing teams is the game "Star Struck" disclosed in U.S. Pat. No. 4,932,667. It includes a playing board containing a star shaped playing path, game pieces and cards. The game "Star Struck" requires the performing player of the playing team to provide an audition which is typical of an audition required from a performing artist in a number of known performing arts fields. Incorporated with the audition requirement is the concept of observation by the remaining members of the playing team to determine specific information from the performance in order to develop multi-part answers to specific team questions. Movement is determined initially by the roll of a die and subsequently by game cards and correct answers to multi-part team questions. The game "Star Struck" is based upon a performing player's use of verbal and acting skills, personal experience, and knowledge to perform an impromptu audition. It also relies on the playing team's general and specific knowledge of the performing arts fields, as well as the playing team member's ability to interpret the performing player's audition performance. The object of game is to be the first team to make a complete circuit around the board clockwise returning to the start position.
These prior art educational devices promote competition amongst the individual players or teams using the devices. No attempt is made by the prior art to promote mutual cooperation amongst the individual players to maximize the learning experience such that the focus is on how the game is played instead of winning or losing.
Finally, the majority of the prior art educational devices provide instruction on a single subject matter area and can not readily be changed to expand the teaching to other subject matter areas thereby limiting the utility of such devices.
SUMMARY OF INVENTION
The present invention provides an educational device employing charades, and question and answer in a game situation to teach various subject matter. In the preferred embodiment, religious subject matter is taught. The educational device is typically comprised of a playing board having a plurality of contiguous spaces extending in a path parallel to the perimeter and converging on the center thereof, a plurality of non-contiguous spaces located on various portions thereof, a plurality of card decks, a plurality of markers, and a chance means which may be sequentially operated.
Contained in certain of the contiguous spaces are indicia corresponding to categories of the subject matter area. Associated with said contiguous spaces is a deck of cards. Each card in said deck bears a subject matter text entry for each of said indicia. Associated with particular contiguous spaces is another deck of cards. Each card in said deck bears an answer and the appropriate question thereof or specifically directs player interaction/movement. The remaining contiguous spaces specifically direct player movement. The non-contiguous spaces serve as holding areas.
The object of the game is to reach the central area of the game board and collect as many scoring marker as possible while traveling through the contiguous and non-contiguous spaces. At each turn, the player initially advances in accordance with a chance device. The chance device directs the player to one of the contiguous spaces. If the contiguous space is associated with one of the categories of the text entry card deck, the player is required to silently convey the text to the other players in a charade manner, and if conveyed successfully, the player is awarded the marker quantity indicated on the card. For the particular contiguous spaces associated with the card deck containing answer-question and interaction/movement type cards, the player proceeds as follows. If an answer-question type card is drawn, the the player is read the answer and required to guess the corresponding question on the card, and if guessed correctly, the player is awarded the marker quantity indicated on the card. If the card drawn is a player interaction/movement type card, the player is required to follow the directions on the card. If the contiguous space is not associated with a card deck. The player is required to follow the directions on the contiguous space. The turn of the player ends after the player's last directive and begins with chance means on the player's next turn. Typically, the text entry cards and answer-question cards bear religious subject matter, although obviously any subject matter may be employed.
The present invention is based upon a presenting player's use of personal Bible knowledge, life experience, and charade skill to silently convey specific details of the Bible. It also relies on the Bible knowledge, life experience and perceptiveness of the other players to recognize and identify the specific details of the Bible. The present invention is also based upon a player's use of personal Bible knowledge to formulate the appropriate question associated with the answer read aloud to that player.
One advantage of the present invention is that the educational device provides a high level of player animation through the use of aspects of charades in addition to question and answer. The majority of the player interaction occurs away from the game board while each presenting player attempts to silently convey the specific details of the Bible to the other players in the allotted time.
Another advantage of the present invention is that the educational device provides a greater degree of challenge by prohibiting verbal communications and use of props during the player's presentation.
Yet another advantage of the educational device is the additional challenge experienced while trying to determine the appropriate question for a given answer. Unlike the typical game situation where there is only one correct answer to a particular question, in the present invention, there is often more than one question which could correctly correspond to a given answer. The player must guess the accompanying question in the allotted time.
Yet another advantage of the present invention is the random element introduced by the interaction/movement cards in the deck which directs inter-play and marker movement from the primary playing path to the non-contiguous spaces. In certain cases, it affords the player an advantage. In most cases, it provides a penalty as described hereinafter.
Another advantage of the present invention is that it replaces many of the competitive aspects found in prior art with cooperative ones. The players or playing teams are not matched one against the other. Instead, each player is encouraged to do their best while trying to help and encourage the other players. For example, during a presentation, once the other players recognize and identify the specific detail of the Bible being presented, the presenting player receives a scoring marker. However, the presenting player must in turn make a significant statement about the specific detail of the Bible which extends beyond the detail itself so that the other players may learn from it. There are also opportunities for a player to give their turn to another player which is in need.
Yet another advantage of the educational device given the foregoing is that during the presentations, all players participate instead of having one or more players idle while a particular player or team takes their turn.
Another advantage of the present invention is that a player has the opportunity to earn a scoring marker after an unsuccessful answer-question turn if they possess a certain playing card and can correctly formulate the question the other player missed as describe herein.
Yet another advantage of the present invention is that it provides a game apparatus for teaching religious doctrine.
Other and further advantages of the present invention will become apparent from the course of the following detailed description.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a top plan view of a game playing apparatus in accordance with the present invention.
FIG. 2 illustrates a text entry categories card for use with the game playing board of FIG. 1 in accordance with the present invention.
FIG. 3 illustrates an answer-question card for use with the game playing board of FIG. 1 in accordance with the present invention.
FIG. 4 illustrates an interaction/movement card for use with the game playing board of FIG. 1 in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, there is shown therein a top plan view of a game playing apparatus 10 in accordance with the present invention. The preferred embodiment of the present invention, shown in FIG. 1, is directed to teaching religious subject matter, although it will be apparent in the course of the following description that the invention may readily be adapted for the teaching of different subject matter. The game apparatus 10 is generally comprised of a foldable game board 12 having a plurality of sides and edges, with one of the sides defining a playing surface 14. The game apparatus 10 further comprises a plurality of card decks 32 associated with the contiguous spaces 18 and 20 described hereinafter, markers 34 for each player, various markers such as yellow, green and blue chips 36 as discussed in detail hereinafter and a chance device 38.
The playing surface 14 includes a plurality of contiguous spaces extending in a path parallel to the perimeter and converging on the center thereof and a plurality of non-contiguous spaces located on various portions thereof. Included in the contiguous spaces is a first space 16 which in the embodiment of FIG. 1 is labeled "START". A group of contiguous second spaces, shown generally as 18, contain indicia thereon. These spaces are associated with the categories of the text entry card deck 32. In the preferred embodiment, the subject matter represented by the text entries extracted from the Bible is divided into a plurality of categories, for example, 1--Persons, 2--Places, 3--Things, 4--Groups, 5--Phrases, and 6--Events as better illustrated in FIG. 2. A group of contiguous third spaces, generally shown as 20, in the embodiment of FIG. 1 contain a question mark symbol. These spaces are associated with the answer-question and interaction/movement card deck 32. In the preferred embodiment, the subject matter of a primarily doctrinal nature is represented by the answer-questions extracted from the Bible as better illustrated in FIG. 3. The remaining cards in the deck direct player interaction/movement. Certain of these cards direct the player to the non-contiguous space 26 labeled "TRIAL" in the preferred embodiment of FIG. 1. The remaining contiguous spaces direct player movement. In the preferred embodiment of FIG. 1, contiguous spaces 22 are labeled "GO TO PLACE OF SAFETY" to direct player to the non-contiguous space 28 labeled "PLACE OF SAFETY" Contiguous space 24 labeled "STRAIT GATE" in the embodiment of FIG. 1 serves as an entry point to central area 30 of the game board labeled "FINISH" where play terminates.
FIG. 2 illustrates the playing side of a text entry card 40 contained in the categories text entry card deck 32. The subject matter extracted from the Bible is divided into a plurality of categories which correspond to the indicia indicative of the predetermined number of subject matter categories defined by the group of second spaces 18 on the playing surface 14 of FIG. 1. In the embodiment of FIG. 2, there are six subject matter categories illustrated, which are: (a) person represented by indicia 46; (b) place represented by indicia 48; (c) thing represented by indicia 50; (d) group represented by indicia 52; (e) phrase represented by indicia 54; and (f) event represented by indicia 56. Also included on the playing side of the text entry categories card 40 is the number of scoring markers 58 to be awarded.
FIG. 3 illustrates the playing side of an answer-question card 42 contained in the answer-question and interaction/movement card deck 32. The subject matter extracted from the Bible is presented in the form of an answer 60 and a question 62 corresponding to the answer. Also included on the playing side of the answer-question card is the number of scoring markers 64 to be awarded.
FIG. 4 illustrates the playing side of an interaction/movement card 44 contained in the answer-question and interaction/movement card deck 32. In the preferred embodiment, an interaction/movement card bears an instruction 66 which specifically directs player interaction or movement, such as, "You may respond in in the PLAYER'S STEAD", "You may GIVE TURN to another player", "ADVANCE to Strait Gate from inner spaces if you gave turn to another player", "TRIAL You lose all but one Marker", and "TRIAL You lose 2 Markers Go to trial box". One such example is shown in FIG. 4.
To begin play, all card decks 32 should be shuffled and placed in position with playing side down. Each player should select a marker 34 and place it in the contiguous first space 16 labeled "START". Each player should take a plurality of scoring markers 36, specifically five yellow markers. The marker color indicates it's score value. Each yellow marker has a score value of one unit. Each green marker is worth five yellow makers (five units) and each blue marker is worth two green markers (ten units). Markers may be exchanged as follows: After accumulating ten yellow markers, five of the yellow markers may be exchanged for a green marker. And, after three green markers have been accumulated, two of the green markers may be exchanged for a blue. The yellow marker is the marker which is awarded during play. Marker exchanges are performed to replenish the quantity of yellow markers in the marker bank.
The order of play may be determined by sequential operation of the chance device 38, such that the starting player is the player obtaining the highest number indicated by the chance device. The play then proceeds clockwise from the starting player. The starting player begins play by operating the chance device 38 to exit the starting space 16. The player moves player marker 34 clockwise the number of spaces indicated by the chance device 38.
If the player lands on one of the second spaces, shown generally as 18 in FIG. 1, the players draws a single card 40, as illustrated in FIG. 2, from the text entry categories card deck 32. The card 40 bears thereon a plurality of text entries, one for each category, together with the number of scoring markers 58 to be awarded. The player silently presents the text entry on the card that corresponds to the space on which the player marker is located. The presented text entry must be identified by the other players in the allotted time which is three minutes in the preferred embodiment. After the text has been guessed and the presenting player has stated a significant fact relating to the text, the presenting player is awarded the number of markers indicated on the card. The card is then place at the bottom of the deck.
If the player lands on one of the third spaces, shown generally as 20 in FIG. 1, the individual to the right of player draws a single card from the answer-question and interaction/movement card deck 32. If an answer-question card 42, as illustrated in FIG. 3, is drawn, the player attempts to guess the corresponding question 62 after being read the answer 60. The card 42 also bear thereon the number of scoring markers 64 to be awarded. In the preferred embodiment, the question must be guessed in the allotted time of three minutes. After the question has been successfully determined, the guessing player is awarded the number of markers indicated on the card. The card is placed at the bottom of the deck. If an interaction/movement card 44, as illustrated in FIG. 4, is drawn, the player proceeds according to the instructions 66 as follows:
A card displaying the words "You may respond in PLAYER'S STEAD" entitles the player to respond after the missed answer-question turn of another player. The card is held until such a situation occurs. The player using the card must: (a) wait until the other player's time has expired, (b) state that they are responding in that player's stead, and (c) attempt to guess the question. Only one guess is allowed. If the player's guess is correct, the scoring marker(s) 64, indicated on card 42 of FIG. 3, are awarded the player giving the response. If neither response is correct, no scoring marker(s) are awarded. The individual reading the answer-question card is not entitled to use a player's stead card in conjunction with that turn.
A card displaying the words "You may GIVE TURN to another player" allows the player to give the current turn to another if so desired. If the player decides to give the turn away, the card is passed to the appropriate player. When the card holder's turn arrives, that player takes two turns. After the second turn, the card is placed at the bottom of the deck. If the player decides not to give the turn away, the card is placed at the bottom of the deck and a second card is drawn by the individual to the right of the player. That card is placed at the bottom of the deck after it has been used.
A card displaying the words "ADVANCE to Strait Gate from inner spaces if you gave turn to another player" entitles the player to move player marker 34 directly to contiguous space 24, labeled "STRAIT GATE", if player marker is currently on one of the contiguous spaces surrounding the central area 30, labeled "FINISH", and player has given away a turn during the course of play. The card is held until such situation occurs. After the card is used, it is placed at the bottom of the deck.
A card displaying the word "TRIAL" requires the player to move player marker 34 from current contiguous third space to non-contiguous space 26, labeled "TRIAL", provided the contiguous third space is not one surrounding the central area 30, labeled "FINISH". The player may also be required to relinquish a certain quantity of scoring markers to the marker bank as indicated on the card. The card is placed at the bottom of the deck.
Once on non-contiguous space 26, labeled "TRIAL", the player is required to successfully convey the text entry of a card selected from the text entry categories deck 32 in order to move player marker 34 to the contiguous second space immediately adjacent to non-contiguous space 26. The number obtained from chance device 38 is used to determine the text entry category rather than the number of spaces to advance during turn. If the text is conveyed in the allotted time of three minutes in the preferred embodiment, the player marker is moved to the adjacent contiguous second space. The player also receives a scoring marker. If the text is not conveyed, the player remains on non-contiguous space 26.
If player marker lands on one of the contiguous spaces 22, labeled "GO TO PLACE OF SAFETY", the player must move player marker to non-contiguous space 28, labeled "PLACE OF SAFETY". During subsequent turns, the player with player marker 34 on space 28 is required to successfully convey the text entry of a card selected from the text entry categories deck 32, in order to move player marker to contiguous space 24, labeled "STRAIT GATE". The number obtained from chance device 38 is used to determine the text entry category rather than the number of spaces to advance during turn. If the text is conveyed in the allotted time of three minutes in the preferred embodiment, the player marker is moved to contiguous space 24, the player is awarded a scoring marker, and the player is allowed an additional turn. If the text is not conveyed, player marker remains on non-contiguous space 28.
If player marker is located on contiguous space 24, labeled "STRAIT GATE", the player is required to successfully convey the text entry of a card selected from the text entry categories deck 32, in order to move player marker to central area 30, labeled "FINISH". The number obtained from chance device 38 is used to determine the text entry category rather than the number of spaces to advance during turn. If the text entry is conveyed in the three minute time requirement of the preferred embodiment, the player marker 34 is moved to central area 30, labeled "FINISH". The player also receives a scoring marker. If the text entry is not conveyed, player marker remains on contiguous space 24.
Upon reaching central area 30, labeled "FINISH", the player obtaining the highest score, based on the quantity of scoring markers possessed, is the winner. Play ends when all player markers 34 reach central area 30 or the remaining player or players with marker(s) outside central area 30 concede.
In the preferred embodiment of FIG. 1, the numerals "1" through "6" are used as indicia to associate the contiguous second spaces, generally shown as 18, with the text entries of the text entry categories card deck 32 as shown in FIG. 2. In other embodiments of the game apparatus 10 of FIG. 1, color coding, icons, or a combination of the two can be used to associate the contiguous second spaces with the text entries of the text entry categories card deck 32.
Having described the invention, it is understood that many variations including those described will be obvious to those skilled in the art without departing from the spirit of the invention herein. | An educational device employing charades and answer-based question formulation in a game situation to teach subject matter of a particular religious nature is disclosed. The educational device is typically comprised of a playing board having a plurality of contiguous spaces extending in a path parallel to the perimeter and converging on the center thereof. Certain of the contiguous spaces contain indicia which correspond to subject matter area categories and associated subject matter area text entries on the cards of a card deck. Certain of the contiguous spaces correspond to a card deck containing question-answer and player interaction/movement cards. The remaining contiguous spaces specifically direct player movement. The playing board also contains a plurality of non-contiguous spaces located on various portions thereof. A plurality of markers are used by the players and chance means initially directs player movement about the board. Players are awarded or required to relinquish scoring markers based on the completion of particular game tasks and the information contained on selected game cards. The object of the game is to reach the central area of the game board and collect as many scoring markers as possible while traveling through the contiguous and non-contiguous spaces. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a portable floor system and in particular to an improved locking assembly and mounting system for the locking assembly.
[0003] 2. Description of the Prior Art
[0004] Portable floors generally have a number of interlocking, rectangular sections or panels and are used for providing an extended hard surface that may be set up over carpeting or other surfaces on a temporary basis, by joining the floor sections together in an edge-to-edge relationship. Locks or other connectors are provided along the edges of the panels to secure the adjacent panels together to form the extended floor surface.
[0005] Portable floors are used for a variety of purposes and are particularly useful in the hospitality and entertainment industry. It is often desired to provide a temporary smooth hard surface for dancing or other activities that can be removed so the space may be used for other activities. Floors are usually connected together in an edge-to-edge fashion with releasable locks along their edges. A portable floor of this general type is disclosed in U.S. Pat. No. 3,310,919, which discloses floor panels with each floor panel having an extruded tongue section along certain edges and a complementary extended groove section along certain other edges. The adjoining sections can be fitted together in an edge-to-edge relationship by a tongue and groove arrangement and held in place by threaded locking screws mounted above the grooves to engage notches in the tongue members. Although the portable floor disclosed in that patent has been successful in providing a convenient and efficient portable floor, further improvements are possible.
[0006] Another patent showing portable floors is U.S. Pat. No. 6,128,881. Cam-type rotary locks having complementary male and female members on the edge of the panels are used to engage and lock the panels together in proper alignment. Although the cam-type rotary locks are an improvement, there are challenges with mounting such locks. As weight is a concern in the portable floor panels, it is often desired to utilize a panel construction having a light weight core panel to reduce overall weight. Although using core materials such as foam, honeycomb or balsa wood aids in reducing weight, these materials are not suitable as a mounting structure. Prior methods of mounting the rotary locks to the floor panel with a core that provides little support is difficult. Moreover, such systems are difficult to replace when failure occurs. Typically, a portion of the core is removed and a wood block is inserted for mounting by joint connector nuts and bolts or mounting using standard wood screws. Such a system requires a precise alignment for a joint connector bolt inserting into a complementary joint connector nut having a complementary orifice. Great precision is required for aligning the nuts and bolts. Moreover, such systems using either wood screws or joint connector require drilling of a pilot hole. Improper positioning of such pilot holes may ruin the panel during the manufacturing process.
[0007] In addition, such systems are difficult to repair should failure occur. Although the rotary locks are generally held by at least two screws or joint connector bolts, they typically have four mounting holes. However, due to the proximity between the holes, if failure occurs, the adjacent hole is typically too close to the position of the failure to allow for repair and mounting of a separate joint connector nut and bolt.
[0008] A further problem is the precise alignment that is required and the special manufacturing methods needed to align all of the various elements. The anchoring block and the rotary lock member are also spaced apart with light weight core material or alternate fill material between the elements when mounted so that when force is applied, the material between the wood block and the lock member can collapse, which can lead to failure and/or misalignment.
[0009] Another problem with portable floors is alignment of wood grain surfaces to provide continuity. Due to imprecise manufacturing, floors that have aligned wood grains have been difficult to achieve. It can be appreciated that a method that provides for properly aligning and orienting the wood grain so that the pattern on the top surface is consistently placed so that each panel has an identical appearance and aligns with any other panel improves overall appearance of the floor system.
[0010] It can be seen that a new portable floor system using new and improved portable floor panels is needed that overcomes the problems related to locking assemblies and their mounting. Such a system should provide for simple and easy insertion and manufacture of the floor panel and the locking devices. Such a system should also eliminate soft core material between the locking member and the anchoring element. Such a system should also improve alignment and provide a light weight anchor that is easily replaced should failure occur. The present invention addresses these, as well as other problems associated with portable floor systems.
SUMMARY OF THE INVENTION
[0011] The present invention is directed to a portable floor system and in particular to a floor system wherein the individual floor panels have an improved mounting assembly for mounting the arrangement for the locking assemblies.
[0012] The portable floor system of the present invention provides a temporary floor surface that is suitable for dancing or other activities while providing multi-use capability for the space where the floor is removed. The present invention provides a portable floor having substantially rectangular floor panels connecting and locking along their edges to form a continuous extended floor surface. Along the edges of the floor are edge trim panels that provide a transition from the portable floor surface to the underlying surface.
[0013] Each of the floor panels includes a planar floor portion with an extruded edge section. These edges form complementary tongues and grooves for aligning the panels together. The panels are locked together by a cam-type rotary lock having complementary male and female members on the edges of adjacent panels. As the cam locks engage, the camming action tends to slide the panels relative to one another along the edges, thereby locking the panels together and ensuring a proper fit with no gaps between the panels. The present invention provides for a lightweight and easy to manufacture mounting arrangement for the locking assemblies. The lock members attach directly to an anchor element mounted into a slot formed in the floor panel. The anchor element is a light weight plastic element having holes receiving mounting screws that attach through the locking member directly to the anchor element. The direct mounting eliminates the need for making precise pilot holes as was needed with the prior art lock mounting systems. In addition, the direct abutment of the locking devices to the anchor element provides a stronger rigid mount that eliminates the sagging and compression that may occur if the soft core material between the lock and the mounting blocks of the prior art has pressure applied.
[0014] In addition to a sturdier mounting arrangement, the mounting system of the present invention is also easy to manufacture. A first slot for the anchor element is formed in the bottom of the panel and a second slot for receiving the lock is formed in the edge of the panel to intersect the first slot and form a continuous opening. This provides for mounting the lock member directly against the anchor element for additional support. Moreover, the pattern on the upper surface may be continuous panel to panel and the lock and anchoring elements are aligned off a particular indexing feature of the surface panels so that the various panels are precisely aligned and therefore, can form a continuous wood grain pattern from panel to panel over the entire floor.
[0015] The mounting arrangement also provides for easy replacement as damaged screws may simply be replaced by removing the anchor element and the lock and replacing the damaged pieces. It can also be appreciated that if a mounting screw or hole is stripped, an adjacent hole may be utilized for mounting, thus eliminating the need for replacement of the anchor element. Moreover, the present invention does not require any type of adhesive or special steps for mounting. The anchor element is a rigid light weight plastic material such as nylon, with much of the slot into which it inserts remaining empty so that the mounting system achieves weight savings over the prior art systems.
[0016] These features of novelty and various other advantages that characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof. However, for a better understanding of the invention, its advantages, and the objects obtained by its use, reference should be made to the drawings that form a further part hereof, and to the accompanying descriptive matter, in which there is illustrated and described a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a top plan view of a portable floor system according to the principles of the present invention;
[0018] FIG. 2 is a bottom exploded perspective view of a floor panel for the portable floor system shown in FIG. 1 ;
[0019] FIG. 3 is a top view of the floor panel shown in FIG. 2 with portions removed to show the locking assembly;
[0020] FIG. 4 is a bottom perspective view with portions removed of two panels for the floor system shown in FIG. 1 joined together;
[0021] FIG. 5 is a side sectional view of a portion of the panel shown in FIG. 2 ;
[0022] FIG. 6 is top detail view of the floor panel shown in FIG. 2 showing the locking assembly;
[0023] FIG. 7 is a bottom perspective view of two locking assemblies shown in FIG. 6 and their mounting to the panels with the locking assemblies connected;
[0024] FIG. 8 is a top plan view of a portion of the panel shown in FIG. 2 showing slots for installation of the locking assembly;
[0025] FIG. 9 is a perspective view of the anchor element for the locking assembly shown in FIG. 6 ; and
[0026] FIG. 10 is a side elevational view of an anchor element shown in FIG. 9 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] Referring now to the drawings, and in particular to FIG. 1 , there is shown a portable floor system, generally designated 10 . The floor system 10 includes a plurality of generally rectangular floor panels 12 joined in an edge-to-edge relationship to form an extended, continuous floor surface. Such panels generally include a lightweight planar portion 14 with an extruded edge elements including tongues 16 along two edges and grooves 18 along the other two edges. With this arrangement, the tongues 16 insert to the corresponding grooves 18 and provide engagement of the edges of adjacent panels.
[0028] Referring now to FIG. 5 , the planar portion 14 typically includes a light weight center core layer 20 , a hard bottom exterior layer 22 and a bottom inner support layer 24 . A top support layer 28 extends over the core layer 20 and a top exterior layer 26 covers the top support layer 28 . The top exterior layer 26 may have a pattern and in one embodiment, includes a wood grain pattern to give the impression of a hardwood floor. It can be appreciated that fewer or more layers may be utilized, depending upon the use, but should include a lightweight core layer 20 . Referring again to FIG. 1 , the wood grain layer 70 is a continuous repeating pattern and includes a designated indexing feature 72 that it utilized for positioning the necessary cuts and for positioning the edges of the panel and the so that the pattern is continuous from one panel 12 to the next.
[0029] Referring again to FIG. 1 , the floor system 10 also includes edge trim pieces 30 and 32 . The edge trim pieces 30 and 32 form a safe transition from the upper surface of the floor system 10 to the underlying ground or floor. The edge trim pieces 30 and 32 have either tongues or grooves (not shown) similar to the tongues and grooves of the extruded edge 16 and 18 and mate in a similar manner. As explained hereinafter, the edge trim pieces 30 and 32 have corresponding locking devices that also engage complementary locking devices of the floor system 10 .
[0030] Referring now to FIGS. 2, 3 and 4 , the floor panels 12 are shown with the planar portions 14 and the extruded edge members including tongues 16 and grooves 18 . The tongues 16 are along two adjacent sides while the grooves 18 are along the two adjacent opposite sides. The tongues 16 engage the complementary grooves 18 of adjacent panels 12 so that the edges of the floor panels 12 abut and the floor panels 12 form an extended continuous floor surface.
[0031] The floor panels 12 are connected to one another with lock assemblies 40 , as shown more clearly in FIG. 7 . Referring again to FIGS. 2-4 , the lock assemblies include female locks 42 and complementary male locks 44 . The complementary rotary locks 42 and 44 provide for pulling the edges together to ensure a tight fit. The female rotating cam lock devices 42 have a rotatable circular cam and mount at the center of the two edges having grooves 18 . The complementary male cam lock members 44 mount at the center of the edges having tongues 16 and receive and retain the rotary cam member when the lock is actuated and the cam member extends into the male lock member 44 . The female cam members 42 are actuated by rotating the cam with an Allen-type tool inserted into an orifice 64 in the upper surface of the floor panels 12 . When actuated, the cam pulls the cam lock devices 42 and 44 and therefore the floor panels 12 together to ensure that no gaps are formed in the floor 10 and a tight edge-to-edge connection is maintained between adjacent panels 12 .
[0032] Referring now to FIGS. 5-7 , the improved mounting arrangement of the lock assemblies 40 of the present invention is shown. The lock assemblies 40 include the bodies of the female and male lock members 42 and 44 that mount directly into slots 66 formed through the tongues 16 and grooves 18 of the edges and slots 62 formed in the planar panel portion 14 . The female lock devices 42 and the male lock devices 44 mount directly to an anchoring element 48 . The slots 62 are formed in the edges of the center core of the planar portion 14 . The anchoring element fits into a slot 60 , shown most clearly in FIGS. 2 and 8 . Mounting screws 46 extend through the back of the female and male locks 42 and 44 and into receiving portions 52 of the anchoring element 48 , shown most clearly in FIG. 9 . It can be appreciated that with this arrangement, the lock devices 42 and 44 mount directly to the anchoring element 48 and abut the anchoring element, thereby eliminating the less dense and poorly supporting material of the lightweight center layer 20 of the prior art. The anchoring element 48 provides added support for the lock members 42 and 44 . Moreover, installation is straight forward and requires no special tools or application of adhesive.
[0033] Should damage occur, repair is simple so that the panel 12 is not ruined. If a mounting screw 46 or orifice 52 is stripped, a new screw may simply be inserted into the adjacent unused receiving orifice 52 and no replacement parts are needed. It can be appreciated that if the anchoring element 48 or other elements do need to replacement, they are simply removed with a screwdriver and new lock devices 42 or 44 or anchoring elements 48 may be remounted without any adverse effect to the floor panel 12 .
[0034] The anchoring element 48 provides further advantages over the prior art wood mounting blocks. The anchoring elements 48 are preferably made of a sturdy but light weight plastic material such as nylon 6/6 or other suitable material well known in the art. The plastic material includes an upper flange 50 that extends slightly around the slot 60 and over a portion of the bottom of the floor panel 12 . Horizontal ribs 56 and vertical ribs 54 provide a sturdy support structure for the mounting portions 52 . As the anchoring element 48 provides much empty space, it provides weight savings over solid wood block mounting systems.
[0035] Forming of the slots 62 and 60 is accomplished quite simply with a router and is positioned to ensure a proper placement from an indexing feature 72 of the surface pattern 70 . The edges of planar portion 14 are formed at the same time as the slots 60 and 62 so that the slots 60 and 62 are precisely located to ensure proper alignment of the lock devices 42 and 44 . This also provides sufficiently precise alignment to ensure that the patterns that are configured for being continuous are consistently aligned and oriented to give an improved overall continuous natural wood grain or other floor appearance.
[0036] It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. | A portable floor system having a plurality of floor panels configured for connection along abutting edges to form an extended floor surface. Each panel has a planar portion including a top surface, a core, and a bottom surface. Extruded edge portions include tongues along two edges and complementary tongues along the other two edges. Each edge also includes a panel connecting assembly along each edge, having a lock device extending from an edge into the core. The lock device mounts directly against an anchor element. The anchor element extends through the bottom surface and having a connector receiving portion. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention concerns the technical field of lignin separation. In particular the present invention relates to a method for lignin separation from spent cooking liquor, called black liquor. Further the invention relates to a lignin product obtainable by the above mentioned method and use of said product.
2. Description of Related Art
In a modern, energy-optimized pulp mill, there is a surplus of internally generated energy. With today's modern processes, bark can be exported while the remaining energy surplus, in the form of mixtures comprising other burnable residues, is burned in the recovery boiler, with a relatively low efficiency, especially with regard to electricity production. There is also often a problem because the heat transfer capacity in the recovery boiler is a narrow sector, a so called bottleneck, which limits the production of pulp in the mill. The recovery boiler is further the most expensive (instrument) unit in the pulp mill.
To separate lignin from black liquor is an interesting solution to these problems. In this way, the energy surplus can be withdrawn from the process in the form of a solid biofuel and can be exported to e.g. a power station, where the fuel can be used more efficiently than in the recovery boiler of the pulp mill. This lignin is also a valuable material for production of “green chemicals”. A further alternative to energy production is to use the extracted lignin as chemical feedstock. Further, lignin extraction leaves a black liquor for combustion with a lower thermal value, which in turn leads to a lower load on the recovery boiler. This gives in a short term perspective possibilities for increased pulp production. In the long term perspective lower instrument costs for the recovery boiler are expected.
There are several possible procedures for such a separation, and industrial applications have been known for a long time. Already in 1944, Tomlinson and Tomlinson Jr were granted a patent for improvements to such a method. The separation method used today is to acidify the black liquor so that the lignin is precipitated in the form of a salt. The solid phase is separated from the liquor and can thereafter be cleaned or modified. There are industrial applications in operation today where lignin is separated from black liquor for use as special chemicals. One example of such a process is the precipitation of lignin from black liquor by acidification with carbon dioxide. The suspension is taken to a storage vessel for conditioning of the precipitate after which the solid lignin is separated and washed (with acidic wash water) on a band filter, and is finally processed to the desired state.
However, if the separated lignin is to be used for fuel the demands on cleanliness and properties are completely different from those when the application is for use as a special chemical. A successful washing of the precipitated lignin is very important, to obtain a lignin fuel with a reasonably low ash content and a low tendency to cause corrosion and to be able to return as much as possible of the cooking chemicals to the chemicals recovery unit. Also important is to minimize filtering resistance in order to minimize filtering area as well as promote possibilities to reach a high dry solid content for the lignin production.
In laboratory studies of such a separation mentioned above (which also is found in our experimental part) the result was in some cases a “pure” lignin (sufficiently clean for qualified fuel usage), but relatively large problems arose through blockage of the filter cake. The flow of wash water was reduced to almost zero in some tests. In other tests, an uneven washing of the filter cake occurred with high concentrations of inorganic substances (primarily sodium) in the lignin as a result. These problems could be reduced, as was found during the course of the experiment, by washing with highly acidic washing water (pH=1) in order to obtain the quickest possible reduction of the pH in the filter cake. On an industrial scale, however, such a procedure leads to a very high consumption of acid and accordingly a such procedure is very inefficient.
Accordingly, there is a need for a method where lignin can be separated using small amounts of acid whereby an essentially pure lignin product is obtained which can e.g. be used as fuel or for the production of chemicals. Further it would be desirable that said method achieves a lignin product suitable for use as fuel with reasonably low ash content and a low tendency to cause corrosion.
SUMMARY OF THE INVENTION
The present invention solves one or more of the above problems by providing according to a first aspect a method for separation of lignin, using small amounts of acid whereby an essentially pure lignin product is obtained which can be used as fuel or for the production of chemicals and has a reasonably low ash content and a low tendency to cause corrosion, from black liquor comprising the following steps:
a) Precipitation of lignin by acidifying black liquor (which in itself is a lignin suspension) and thereupon dewatering, b) suspending the lignin filter cake whereupon a second lignin suspension is obtained and adjusting the pH level to approximately the pH level of the washing water of step d) below, c) dewatering of the second lignin suspension, d) addition of washing water and performing a displacement washing at more or less constant conditions without any dramatic gradients in the pH, and e) dewatering of the filter cake produced in step d) into a high dryness and displacement of the remaining washing liquid in said filter cake, whereby a lignin product is obtained which has an even higher dryness after the displacement washing of step d).
The present invention also provides a lignin product or an intermediate lignin product obtainable by the method according to the first aspect. The present invention also provides according to a third aspect use, preferably for the production of heat or chemicals, of the lignin product or the intermediate lignin product of the second aspect. In this way the lignin may be kept stable during the washing course with a more even result as a result thereof due to avoidance of clogging in the filter cake/medium. The method of the first aspect is further illuminated in FIG. 2 . The method avoids re-dissolution of lignin and subsequent blockage of the filter cake.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
FIG. 1 shows sodium and lignin concentrations and pH-profile for the washing of a lignin filtered directed after the precipitation stage.
FIG. 2 shows the method according to the first aspect, incorporating a modified washing process, whereby lignin is precipitated from black liquor.
FIG. 3 shows material balance for the present method according to the first aspect instead of air in filter press 2, hot flue gases can be used.
DETAILED DESCRIPTION OF THE INVENTION
It is intended throughout the present description that the expression “acidifying” embraces any means for acidify the black liquor. Preferably the acidifying is performed by adding SO 2 (g), organic acids, HCl, HNO 3 , carbon dioxide or sulphuric acid (in the form of fresh sulfuric acid or a so called “spent acid” from a chlorine dioxide generator) or mixtures thereof to said black liquor, most preferred by adding carbon dioxide or sulphuric acid.
It is intended throughout the present description that the expression “dewatering” embraces any means for dewatering. Preferably the dewatering is performed by using centrifugation, a filter press apparatus, a band filter, a rotary filter, such as a drum filter, or a sedimentation tank, or similar equipment, most preferred a filter press apparatus is used.
According to a preferred embodiment of the first aspect of the invention the dewatering of step a) is performed in a filter press apparatus where the filter cake may be blown through by gas or a mixture of gases, preferably flue gases, air or vapor, most preferred air or overheated vapor, in order to dispose of the remaining black liquor.
According to a preferred embodiment of the first aspect of the invention the pH level is adjusted to below approximately pH 6 in step b), preferably below approximately pH 4. The pH level is most preferred a pH from 1 to 3.5.
According to a preferred embodiment of the first aspect of the invention the washing water has a pH level of below approximately pH 6, preferably below approximately pH 4. The pH level is most preferred a pH from 1 to 3.5.
According to a preferred embodiment of the first aspect of the invention the filter cake obtained in step a) is blown through by using gas or a mixture of gases, including e.g. flue gases, air and vapor (which preferably can be air or overheated vapor) before suspending said cake as set out in step b).
According to a preferred embodiment of the first aspect of the invention the pH level adjustment is combined with an adjustment of the ion strength, preferably by using alkali metal ions or multivalent alkaline earth metal ions, most preferred calcium ions.
According to a preferred embodiment of the first aspect of the invention the pH level adjustment combined with an adjustment of the ion strength is adapted so that they correspond to the pH level and ion strength of the washing liquid. A higher ion strength gives at a given pH lower yield losses of lignin as the lignin becomes more stable.
According to a preferred embodiment of the first aspect of the invention the filtrate from the first dewatering stage step a) is re-circulated directly to a recovery system, preferably after re-alkalization.
According to a preferred embodiment of the first aspect of the invention the remaining washing liquor in the filter cake in step e) is removed with air or flue gases, preferably flue gases from a recovery boiler, a bark boiler or a lime kiln.
According to a preferred embodiment of the first aspect of the invention the washing liquor and a part of the filtrate from the second dewatering in step c) is returned to the re-slurrying stage step b) to further reduce the consumption of acid and washing liquid, i.e. water.
The method according to the first aspect of the invention solves the above mentioned problems and said method gives a more uniform result without blockage of the filter cake/medium (see FIG. 2 ). The central feature of said method is that the changes in the lignin particles/suspension take place before the washing, instead of during the washing process itself. As before, the lignin is precipitated from the black liquor by acidification and is then dewatered. Instead of the previous direct displacement washing, however, the filter cake is stirred into a quantity of wash water and a new slurry is obtained. In this slurry, the pH can be adjusted to correspond to the level of the wash water, as set out in the method according to the first aspect. Thereafter, the suspension is dewatered, wash water is added and a displacement washing can be carried out under more or less constant conditions without any dramatic gradients in pH or ionic strength. In this way, the lignin can be kept stable during the washing process. Changes, if any, take place in the suspension stage instead of during the washing process as set out earlier.
An alternative procedure for stabilizing the lignin during the washing as set out above earlier as a preferred embodiment of the first aspect of the present invention is, in combination with a pH-decrease, to adjust the ionic strength in the slurry stage, preferably with multivalent alkali metal ions or alkaline earth metal ions (e.g. calcium). At a given pH, a higher ionic strength in the suspension stage reduces the lignin yield losses. Here also the ionic strength and pH of the wash water preferably essentially correspond to the conditions in the slurry stage to avoid gradients during the washing process. A higher ionic strength in the slurry and in the wash water gives a stable lignin even at high pH-values. Besides making the washing easier, divalent calcium ions can be introduced into the lignin, which in the combustion of the lignin can bind sulfur in the form of calcium sulphate (Aarsrud et al 1990).
If the pH in the slurry stage is kept on the acidic side, sulfur will be released from the black liquor in the form of hydrogen sulfide- and/or sulfide ions (which in turn may end up in hydrogen sulfide (H 2 S)). Such a sulfur separation can be useful in the pulp process in two different ways. If the hydrogen sulfide is e.g. re-absorbed in the cooking liquor before chip impregnation, a higher selectivity can be obtained in the pulp cook. Other possibilities are internal sulfuric acid or polysulfide generation.
The method according to the first aspect of the present invention may further be performed, as set out above, whereby first the lignin is precipitated with carbon dioxide or other suitable acid according to previously known methods. The suspension is then dewatered in some form of separation equipment (e.g. some form of filtration equipment, sedimentation tank, centrifugation etc). A filter press equipment where the filter cake can be pressed to a high dry content is preferable. Thereafter, air is preferably blown through the pressed filter cake in order to remove as much as possible of the remaining black liquor. In this way, the acid consumption and hydrogen sulfide formation in the subsequent re-slurry stage can be considerably reduced. The filtrate from the first dewatering stage is preferably re-circulated directly to the recovery system, possibly after re-alkalization.
Thereafter, the filter cake is again made into a slurry in a tank or similar vessel preferably equipped with a suitable stirring device and also preferably equipped with an exhaust to take care of the hydrogen sulfide formed. The new slurry is then adjusted to the desired pH and preferably also the desired ionic strength and dewatered in another, second, filter press (or apparatus of similar type or apparatus which gives a similar result as set out earlier above) where the cake is pressed to the highest possible dry content before, in the same (or similar) equipment, being washed by displacement washing, where the wash water has the same conditions as the suspension with regard to pH and ionic strength. Finally, the cake is pressed to a high dry content and the remaining washing liquor in the filter cake is removed with air or flue gases from e.g. a recovery boiler or bark boiler. The latter also makes it possible to obtain a drier lignin. The washing liquor and a part of the filtrate from the second filtration can preferably be returned to the re-slurrying stage to further reduce the consumption of acid and water.
Preferred features of each aspect of the invention are as for each of the other aspects mutandis. The prior art documents mentioned herein are incorporated to the fullest extent permitted by law. The invention is further described in the following examples in conjunction with the appended figures, which do not limit the scope of the invention in any way. Embodiments of the present invention are described in more detail with the aid of examples of embodiments and figures, the only purpose of which is to illustrate the invention and are in no way intended to limit its extent.
EXAMPLES
Example 1
Comparative
In laboratory studies of a separation of lignin according to previously known techniques as set out in the background above, lignin was precipitated from black liquor through acidification (with carbon dioxide or sulphuric acid). The suspension obtained was filtered, after which a displacement washing was carried out where the wash water was added on top of the filter cake and was pressed through it under an applied pressure. The result was in some cases a “pure” lignin (sufficiently clean for qualified usage as a fuel), but relatively large problems arose through blockage of the filter cake. The flow of wash water was reduced to almost zero in some tests. In other tests, an uneven washing of the filter cake occurred with high concentrations of inorganic substances (primarily sodium) in the lignin as a result.
These problems were shown to depend on re-dissolution of the precipitated lignin during the actual washing procedure, when the ionic strength in the solution was reduced at the same time as the pH remained high (See FIG. 1 ). A peak in the amount of re-dissolved lignin was observed in a region just after the breakthrough in the washing curve. The problems could be reduced, as was found out during the course of the experiment, by washing with highly acidic washing water (pH=1) in order to obtain the quickest possible reduction of the pH in the filter cake. On an industrial scale, however, such a procedure leads to a very high consumption of acid and accordingly such a procedure is very inefficient.
Example 2
The method of the first aspect of the invention, including the washing process as set out earlier, has been studied experimentally on a laboratory scale with good results, since the pH in the suspension after re-slurrying and the pH in the wash water have been kept below 4. Under these conditions, it has been possible to carry out the washing without blockage and with a very clean lignin as a result. The sodium contents in the washed lignin have varied between 0.005 per cent by weight (for pH 2 in the wash water and suspension) and 0.09 per cent by weight (for pH 3.5 in the wash water and suspension). At a pH of 4 and above in the wash water, blockages were again observed in the filter cake/medium, probably because of re-dissolved lignin which markedly reduced the flow of the wash water. Even in these cases, the sodium contents in the washed lignin could be reduced to ca. 0.25%. A number of test series have been carried out, with reproducible results.
Example 3
A further example is here given of an application of the method according to the first aspect of the invention described above (see also FIG. 3 ). In a pulp mill with a production of 2000 adt/day, 30% of the black liquor is taken from the evaporation at a dry content of 30%. This is acidified to pH 10 at room temperature with carbon dioxide (120 t/d) with stirring at a temperature of 80° C. The resulting slurry is dewatered in a filter press equipment, after which the filter cake is pressed and blown with air to a dry content of ca. 70%. The filtrate is returned to the recovery system of the mill. The filter cake is converted into a slurry in re-circulated washing liquor from the other filter press and is acidified further to pH 4 with sulfuric acid (96%, 12 m 3 /d). The slurry thus obtained is dewatered in a filter press and pressed. The filtrate is returned to the mill's recovery system. Wash water is added and the lignin is washed by displacement washing (541 ton/d washing liquor at pH 4). After blowing with air, 244 t/d lignin (on a dry basis) with a sufficient cleanliness for use as a biofuel is withdrawn from the process at a dry content of 70%.
A comparison with a conventional method for removing lignin shows that the acid consumption (CO 2 and H 2 SO 4 ) and water consumption in the ideal case lie at the same levels. A significant saving in the amount of added sulfuric acid can be achieved through recirculation of filtrate and washing liquor to the slurry stage. The fact that the amount of wash water may seem small in the example is due to the choice of more suitable equipment and not to the new method in itself. Higher dry contents can be reached in the dewatering with a filter press than with e.g. a band filter. The great difference with the new method according to the first aspect is that it offers a more uniform dewatering, which gives a considerably cleaner product. Additionally a significant amount of acid can be deducted when using said method.
In a comparison with a mill without lignin removal, there is also, in addition to the advantages mentioned above, an increased evaporation requirement. This depends largely on the fact that dry substance is removed from the black liquor, and that a larger amount of water thus needs to be evaporated to reach the same dry content to the recovery boiler, together with the added wash water. The increased evaporation requirement can, to a certain extent, be compensated for by a lower viscosity of the black liquor.
Various embodiments of the present invention have been described above but a person skilled in the art realizes further minor alterations, which would fall into the scope of the present invention. The breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. For example, any of the above-noted methods can be combined with other known methods e.g. for separating lignin from black liquor. Other aspects, advantages and modifications within the scope of the invention will be apparent to those skilled in the art to which the invention pertains.
REFERENCES
Aarsrud W., Bergstroem H. and Falkehag I (1990): “A lignin preparation and a method for its manufacture”, WO 9006964
Tomlinson och Tomlinson Jr. (1944): “Improvements in the Recovery of Lignin from Black Liquor”, U.S. Pat. No. 664,811 | Method for separating lignin from black liquor includes the following steps: a) precipitating lignin by acidifying black liquor and thereupon dewatering, b) suspending the lignin filter cake obtained in step a) to obtain a second lignin suspension and adjusting the pH level to approximately that of the washing water of step d) below, c) dewatering of the second lignin suspension, d) adding washing water and performing a displacement washing at substantially constant conditions without any dramatic gradients in the pH, and e) dewatering the lignin cake produced in step d) into a high dryness and displacing the remaining washing liquid in the filter cake, whereby a lignin product is obtained which has an even higher dryness after the displacement washing of step d). The lignin product or an intermediate lignin product obtained by the method, and its use, preferably for the production of heat or chemicals is also disclosed. | 8 |
This application is a continuation of application Ser. No. 07/370,031, filed Jun. 21, 1989, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a process for preventing the discoloration of paper and paper prevented from discoloring.
More particularly, it relates to a process for preventing the discoloration, in particular, caused by irradiation of paper with light which comprises adding or applying hypophosphorous acid or its salt to the paper at any step during or after papermaking, and to paper prevented from discoloring by adding or applying hypophosphorous acid or its salt thereto.
2. Description of the Prior Art
It is widely known that paper is made by mechanically or chemically treating a vegerable material such as wood to thereby give a pulp such as mechanical, chemical, semichemical, wastepaper, hemp or linter pulp and feeding said pulp into a paper machine.
When an unbleached pulp is fed to a paper machine as such, the obtained paper has an unsatisfactory whiteness. In such a case, the pulp may be bleached through oxidating by using, for example, chlorine, hypochlorites, chlorine dioxide, hydrogen peroxide or oxygen or through reduction by using, for example, hydrosulfite or aqueous sulfurous acid, if desired.
A papermaking process comprises a preparation step where a pulp or a mixture thereof is ground and chemicals such as a sizing agent or a filler are added thereto, a papermaking step where the above mixture is treated with various papermachines, dehydrated, dried and glazed, and a conversion and finishing step where a coating suitable for the purpose is applied onto the surface of the resulting paper. Thus a paper having the desired properties is obtained.
Although the paper thus obtained has a certain whiteness immediately after the production, it suffers from serious discoloration when exposed to sunlight involving UV light. Such a discoloration occurs regardless of the type of the pulp or bleaching.
Recently, the application of so-called high-yield pulps has been more and more increasing in order to efficiently utilize wood resources and to lower waste matters. These high-yield pulps contain a large amount of lignin and thus suffer from significant discoloration upon irradiation with light. This causes a serious problem when these high-yield pulps are employed not only alone but also as a mixture with chemical pulp(s).
It has been attempted to suppress the discoloration upon irradiation with light. For example, it is proposed to add an UV absorber to paper. However this method is disadvantageous in that a large amount of an expensive UV absorber is required and the UV absorber generally has a yellow color, thus imparting an undesirable color to the paper.
It was reported that a low molecular weight mercapto compound such as thioglycerol or thioglycol was effective in the prevention of the discoloration of high-yield pulps caused by light (cf. Tappi Journal, Nov. 1987, 117-122). However this method was inavailable in practice, since it could not give any satisfactory effect and, furthermore, the mercapto compound to be used had an offensive odor.
Thus it has been eagerly desired to establish a process for preventing the discoloration of paper without exerting any undesirable effects on other properties of the paper.
U.S.S.R. Patents No. 485178, No. 542775, No. 697617 and No. 857328 disclose that the use of a hypophosphite in the production of pulp enables the Production of the pulp at a high yield. However it is obvious that the hypophosphite used during the production of the pulp would never substantially remain in the paper. Furthermore, none of these patents discloses an effect of preventing the discoloration of the paper after the completion of the papermaking.
SUMMARY OF THE INVENTION
Under these circumstances, the present inventors have attempted to establish a process for preventing the discoloration of paper caused by light. As a result, they have found that the discoloration of paper can be effectively prevented by adding or applying hypophosphorous acid or its salt to the paper.
Accordingly, the present invention, which has been completed based on the above finding, provides a process for preventing the discoloration of paper which comprises adding or applying hypophosphorous acid or its salt to paper at any step during or after papermaking, and paper prevented from discoloring by adding or applying hypophosphorous acid or its salt thereto.
The process for preventing the discoloration of paper according to the present invention makes it possible to effectively prevent the discoloration of paper caused by light without exerting any undesirable effect on other properties of the paper.
The paper according to the present invention is remarkably prevented from discoloring caused by light.
DETAILED DESCRIPTION OF THE INVENTION
The hypophosphorous acid to be used in the present invention is represented by the following general formula: ##STR1##
Examples of the hypophosphite to be used in the present invention include those of a metal such as lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, zinc, cadmium, aluminum, manganese, nickel, gallium, germanium, tin, organotins such as mono- or dimethyltin, mono- or dibutyltin or mono- or dioctyltin, lead, antimony and bismuth; ammonium hypophosphite; hypophosphites of an aliphatic or aromatic amine such as mono-, di- or trimethylamine, mono-, di- or triethylamine, mono-, di- or tributylamine, mono-, di- or trioctylamine, mono-, di- or triethanolamine, mono-, di- or triisopropanolamine, methyldiethanolamine, stearyldiethanolamine, hexamethylenediamine, ethylenebis (diethanolamine), diethylenetriamine, triethylenetetramine, hexamethylenetetramine, benzylamine, aniline, diethylaniline and diethanolaniline; hypophosphites of a heterocyclic amine such as pyridine, lutidine, toluidine, pyrimidine, pyrazine, piperidine, N-methylpiperidine, piperazine, hexahydrotriazine, morpholine, pyrrole, pyrroline, pyrrolidine, imidazole, imidazoline, imidazolidine, pyrazole, pyrazolidine and indole; hypophosphites of a polymeric amine such as polyvinylpyridine, polydiallylamine and polyethyleneimine; quaternary ammonium hypophosphites such as tetramethyl-, trimethylethyl-, triethylmethyl-, tributylmethyl-, tetrabutyl-, octyldimethylhydroxyethyl-, triphenylmethyl- and tribenzylmethylammonium hypophosphites; and sulfonium hypophosphites such as triethylsulfonium hypophosphite.
Among these compounds, hypophosphites of the group Ia or IIa metals and organic amine hypophosphites are preferable, since they are readily available and hardly toxic.
The amount of the hypophosphorous acid or its salt to be added or applied is not particularly limited. It may be determined depending on the desired level of the prevention of the discoloration or the paper to be treated. Generally speaking, the hypophosphorous acid or its salt may be added in an amount of 0.1 to 20% by weight, preferably 1 to 10% by weight, based on the paper in terms of dry matter.
The method and time for adding or applying the hypophosphorous acid or its salt are not particularly limited. Namely, the hypophosphorous acid or its salt may be added in the preparation step where pulp is ground and various chemicals such as a sizing agent or a filler are added thereto. Alternately a solution of the hypophosphorous acid or its salt may be added to paper or the paper may be impregnated with said solution at any step in the papermaking process wherein the paper is dehydrated, dried and calendered or in the conversion and finishing step wherein a coating is applied to the surface of the paper. Alternately, a solution of the hypophosphorous acid or its salt may be sprayed on the paper after the completion of the papermaking process.
The hypophosphorous acid and most of its salts are either soluble or highly dispersible in water, which brings about an advantage that they can be added or applied in the form of an aqueous solution without requiring any particular procedure.
The paper to be treated according to the process of the present invention is not particularly restricted. Namely, the present invention can be effectively applied to any paper obtained from any pulp. It is particularly effective on those obtained from pulps containing lignin, such as mechanical or semichemical pulps.
The pulp to be used in the papermaking according to the present invention may be either bleached or not.
Furthermore, the paper prevented from discoloring according to the present invention may contain various papermakers' chemicals commonly used in the art. Furthermore, the paper may be optionally coated.
Examples of the papermakers' chemicals include rosin, petroleum resin, synthetic resin and wax sizing agents; starch, polyvinyl alcohol and polyacrylamide surface improvers; polyacrylamide, carboxymethylcellulose, urea resin, melamine and epoxidized polyamidepolyamine resin strengthening agents; and polyethyleneimine and polyacrylamide yield enhancers.
The hypophosphorous acid or its salt to be used in the present invention is effective in preventing the discoloration of paper regardless of the addition of these chemicals.
EXAMPLES
To further illustrate the present invention, and not by way of limitation, the following Examples will be given.
EXAMPLE 1
A 10% aqueous solution of hypophosphorous acid or a hypophosphite was applied to a newsprint of a basis weight of 46 g/m 2 at a dry coating weight of 2.5 g/m 2 followed by drying.
Then the newsprint was exposed to sunlight for one week and the degree of the discoloration was expressed by the difference in the yellownesses measured with a Hunter's colorimeter (ASTM D1925) before and after the exposure.
For comparison, a paper treated with a solution containing no hypophosphorous acid and another one treated with a solution wherein thioglycerol was used instead of the hypophosphorous acid were also tested.
Table 1 shows the results.
TABLE 1______________________________________ Yellowness Hypophosphorous acid after afterNo. or its salt 3 days 7 days______________________________________Comp. Ex.1-1 none 13.7 25.01-2 thioglycerol 10.2 20.5Ex.1-1 hypophosphorous acid 7.5 13.41-2 sodium hypophosphite 6.8 12.71-3 potassium hypophosphite 7.3 13.11-4 calcium hypophosphite 7.7 13.61-5 magnesium hypophosphite 7.6 13.81-6 stearyldiethanolamine 8.6 15.2 hypophosphite______________________________________
EXAMPLE 2
A given amount of a 10% aqueous solution of sodium hypophosphite was applied to a newsprint of a basis weight of 46 g/m 2 followed by drying.
Then the newsprint was irradiated in a fade meter at 83° C. for 3 hours and then the change in the yellowness was examined.
Table 2 shows the results.
TABLE 2______________________________________ Amount of sodiumNo. hypophosphite Change in yellowness______________________________________2-1 none 16.82-2 1 g/m.sup.2 11.42-3 2 g/m.sup.2 8.92-4 3 g/m.sup.2 7.22-5 4 g/m.sup.2 6.32-6 5 g/m.sup.2 6.0______________________________________
EXAMPLE 3
A chemithermomechanical pulp having a whiteness of 77.0, which had been bleached with hydrogen preoxide, was dispersed in a 10% solution of sodium hypophosphite in distilled water at a concentration of 1%. From this dispersion, a handmade paper sheet was produced in a conventional manner and then dehydrated to a moisture content of 50%. Next, it was air-dried and thus a handmade paper sheet of a moisture content of 5% was obtained.
This sheet was irradiated in a fade meter at 83° C. and the change in the yellowness was examined.
For comparison, another sheet produced without using sodium hypophosphite was also tested.
Table 3 shows the results.
TABLE 3______________________________________ YellownessIrradiation Na hypophosphite- Na hypophosphite-time contg. sheet free sheet______________________________________30 min 1.1 5.7 1 hr 3.7 7.4 2 hr 5.9 12.6 3 hr 7.5 16.3 5 hr 10.3 22.4______________________________________
The results of Examples 1 to 3 obviously indicate that the addition or application of the hypophosphorous acid or its salt to paper can remarkably prevent the paper from discoloring caused by light. | A process for treating paper to prevent discoloration when exposed to light which comprises adding 1% to 10% by weight of hypophosphorous acid or its salt based on the paper at any stage during or after paper making and maintaining said hypophosphorous acid or its salt therein. The invention also provides paper which contains hypophosphorous acid or its salt to prevent discoloration when exposed to light. | 3 |
This is a continuation of co-pending application Ser. No. 604,643 filed on Apr. 2, 1984, and now abandoned.
FIELD OF THE INVENTION
This invention relates to orthopedic surgery and, more specifically, to external fixation and bone growth stimulation apparatus.
BACKGROUND OF THE INVENTION
It has been known for three decades that bone structures have bioelectric properties. It is known, for example, that bones tend to be electronegative in areas of compression and electropositive in areas of tension, and that areas of active growth and repair tend to be electronegative. Many workers have demonstrated the phenomenon of electric current stimulated osteogenesis at the cathode. Electric currents, both AC and DC, including pulsating DC, in the range of from about 10 to 100 microamperes is known to stimulate bone growth in some but not necessarily all subjects. The literature on this subject is extensive, see, e.g. Spadaro JA: Electrically Stimulated Bone Growth in Animals and Man, A review of the Literature, Clin. Orthop. 122: 325, 1977.
Implantable electric current bone growth stimulator devices have been reported, see, e.g., U.S. Pat. Nos. 3,745,995; 3,783,880; 3,890,953; 3,915,151; 3,968,790; 4,011,861; 4,052,754; 4,306,564; 4,313,438; 4,315,503; 4,333,469 and 4,414,979. Prostheses having electrically stimulated bone growth devices have also been proposed; see, e.g., U.S. Pat. Nos. 3,964,473; 4,195,367; 4,214,322 and 4,216,548. Non-invasive bone growth stimulators, see, e.g. U.S. Pat. Nos. 4,056,097; 4,066,065; 4,153,060; 4,175,565 and 4,244,373, and bone growth stimulators with specific current and voltage patterns, see, e.g., U.S. Pat. Nos. 4,105,017; 4,266,532; 4,266,533; and 4,315,503, have been described. Semi-invasive bone growth stimulators have also been disclosed, see, e.g., Zimmer, "The Alternate Treatment of Fracture Nonunion, Electrical Stimulation to Induce Osteogenesis, Zimmer USA, Warsaw, Ind. 46580, September 1979 revision, and U.S. Pat. Nos. 3,842,841 and 3,918,440.
U.S. Pat. No. 4,026,304 reviews the state of the art and early developments and is incorporated herein by reference. This patent also discusses the problem of polarization and proposes, as a solution, an implantable source of electric potential to generate a train of electric pulses.
U.S. Pat. No. 3,893,462 discloses another method of bone growth stimulation utilizing electrical signals undulating in both the positive and negative directions in an asymmetric manner reactively coupled to the bone.
The general approach in the prior art has been to provide an electric current bone growth stimulator separately from any external fixation which may be used. While efforts have been made to avoid or mitigate the problem of polarization which results when current flows in a given direction through an electrode. The present invention addresses the problems of external fixation and bone growth stimulation, including the problem of polarization.
SUMMARY OF THE INVENTION
The present invention comprises an apparatus for both fixing a bone fracture and stimulating the bone growth repair of the fracture, while eliminating or at least mitigating the effects of polarization in electric current induced osteogenesis. The present invention includes a method for accomplishing these results. The invention may be described, in its various facets as follows:
A combined external fixation device and bone growth stimulator comprising, in combination: a first pair of fixature pins for extending into a fractured bone, one pin on each side of the fracture site of the bone; a second pair of fixature pins for extending into the fractured bone, on pin on each side of the fracture site of the bone; external fixation frame means for rigidly fixing the position of said first and second pins with the distal end thereof secured to the fractured bone and the proximal end secured proximate the frame means to thereby fix the position of the fractured bone on both sides of the fracture therein and thus fixing the position of the fracture site thereof; at least one cathode each comprising a relatively rigid electrically conductive wire externally insulated along a major central portion thereof, having a biologically compatible electrically conductive distal tip for contacting the fractured bone proximate the fracture therein; means secured to the external fixation frame means for fixing the position of said cathodes with the distal tip in electrical contact with the bone proximate the fracture site therein; means electrically isolating the cathodes and pins from each other thereby preventing electrical contact with one another through the frame means; and means for applying electrical voltage to the cathodes and the pins cyclically for a a plurality of time periods during each cycle, the cathodes at all times having either no voltage or negative voltage applied thereto, the pins having either positive, negative or no voltage applied thereto, either the first pins or the second pins being positive when a negative voltage is applied to any cathode, the voltage application being cycled to cause electron flow from a cathode to the first pins in a first period, from the first pins to the second pins during a second period, from a cathode to the second pins in third period, and from the second pins to the first pins in fourth period
Preferably the apparatus comprises at least two cathodes and the means for applying electrical voltage comprises means to cycle the application of voltage to cause electron flow from one cathode during the first period and from another cathode during the third period.
In a still more preferred embodiment, the apparatus includes four cathodes and the means for applying electrical voltage comprises: means for applying electrical voltage to the cathodes and the pins cyclically for a a plurality of time periods during each cycle, the cathodes at all times having either no voltage or negative voltage applied thereto, the pins having either positive, negative or no voltage applied thereto, either the first pins or the second pins being positive when a negative voltage is applied to any cathode, the voltage application being cycled to cause electron flow from a first cathode to the first pins in a first period, from the first pins to the second pins during a second period, from the second cathode to the second pins in third period, from the second pins to the first pins in fourth period, from the third cathode to the first pins in the fifth period, from the first pins to the second pins in the sixth period, from the fourth cathode to the second pins in the seventh period, and from the second pins to the first pins in the eighth period.
The invention may also be described as a combined external fixation and bone growth stimulating means comprising the combination of: first and second pairs of fixation pins; at least one cathode; frame means for electrically isolating and fixing the position of the pins and cathodes, including means for fixing the first pair of pins fixed one on each side of the fracture site of a bone, the second pair of pins one on each side of said fracture site, and the cathodes proximate said fracture site; and means for applying a voltage for a first period between a cathode and the first pins, during a second period between the first and second pins, during a third period between a cathode and the second pins, and during a fourth period between the second and first pins, the cathode being negative during the first and third periods and neutral during the second and fourth periods, the first pins being negative during the second period and positive during the fourth period.
The invention also comprehends a method of treating a bone fracture comprising the steps of: fixing the site of the bone fracture with an external fixation device, including inserting a first pair of fixation pins one on each side of said site, and inserting a second pair of fixation pins one on each side of said site; fixing at least one cathode with the distal end thereof in electrical contact with the bone adjacent the fracture site therein; and applying a voltage cyclically during odd numbered and even numbered time periods, applying said voltage during odd numbered time periods between a cathode and the pairs of pins alternately, the cathode being negative during said odd numbered cycles, applying said voltage during even numbered time periods between the pairs of pins alternately, the polarity being reversed between said pins during alternate even numbered time periods.
In a specific method of treating a bone fracture, the invention comprises the steps of: fixing the site of the bone fracture with an external fixation device, including inserting a first pair of fixation pins one on each side of said site, and inserting a second pair of fixation pins one on each side of said site; fixing a plurality of cathodes with the distal end thereof in electrical contact with the bone adjacent the fracture site therein; and applying a voltage cyclically during odd numbered and even numbered time periods, applying said voltage during odd numbered time periods between the cathodes alternately and the pairs of pins alternately, the cathode being negative during said odd numbered cycles, applying said voltage during even numbered time periods between the pairs of pins alternately, the polarity being reversed between said pins during alternate even numbered time periods.
The preferred method of treating a bone fracture according to this invention comprises the steps of: fixing the site of the bone fracture with an external fixation device, including inserting a first pair of fixation pins one on each side of said site, and inserting a second pair of fixation pins one on each side of said site; fixing at least four cathodes with the distal end thereof in electrical contact with the bone adjacent the fracture site therein; and applying a voltage cyclically during odd numbered and even numbered time periods, applying said voltage during odd numbered time periods between the cathodes alternately and the pairs of pins alternately, the cathode being negative during said odd numbered cycles, applying said voltage during even numbered time periods between the pairs of pins alternately, the polarity being reversed between said pins during alternate even numbered time periods.
In an exemplary embodiment, the method of treating a bone fracture of this invention comprises the steps of: fixing the site of the bone fracture with an external fixation device, including inserting a first pair of fixation pins one on each side of said site, and inserting a second pair of fixation pins one on each side of said site; fixing at least four cathodes with the distal end thereof in electrical contact with the bone adjacent the fracture site therein; and applying a voltage cyclically during odd numbered and even numbered time periods, the cathodes at all times having either no voltage or negative voltage applied thereto, the pins having either positive, negative or no voltage applied thereto, either the first pins or the second pins being positive when a negative voltage is applied to any cathode, the voltage application being cycled to cause electron flow from a first cathode to the first pins in a first period, from the first pins to the second pins during a second period, from the second cathode to the second pins in third period, from the second pins to the first pins in fourth period, from the third cathode to the first pins in the fifth period, from the first pins to the second pins in the sixth period, from the fourth cathode to the second pins in the seventh period, and from the second pins to the first pins in the eighth period.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the apparatus of this invention, the frame being shown in simplified form.
FIG. 2 is an enlarged perspective view of a portion of the apparatus of this invention.
FIG. 3 is a very schematic view illustrating the principle of application of voltage to the cathodes and pins of FIGS. 1 and 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention is described as applied to the Ace-Fischer (Trademark) external fixation device, which in very simplified form is shown in FIGS. 1 and 2; however, it is to be understood and emphasized that the invention includes and comprehends any external fixation device which is capable of fixing fixature pins and cathodes. The Ace-Fischer (Trademark) external fixation device is described in detail in U.S. Pat. No. 4,308,863.
The invention includes an external fixation device 100 which may be in any configuration. In the depicted embodiment, which is merely exemplary and non-limiting, the fixation device includes a pair of semicircular frame members 102 and 104 secured in spaced relation about the fractured bone by adjustable rod means one of which is depicted at 106. Pin holders 110 and 120 are secured in any convenient manner to the frame members and fix the fixature pins 112 and 114, in holder 110, and 122 and 124, in holder 120, in position. Electrically insulating means 116 and 118 in holder 110 and insulating means 126 and 128 in holder 120 electrically isolate the pins 112, 114, 122 and 124 from each other such that there is no electrical connection between them through the frame. Insulating means may be, for example, Teflon (Trademark) polytetrafluoroethylene or other insulative sleeves. The distal ends of the pins are screwed, or otherwise secured, in the usual manner to the bone. One pair of pins, 112 and 122, are secured one pin on each side of the fracture site, and the other pair of pins, 114 and 124, are secured also one pin on each side of the fracture site. The pins on each side are spaced apart sufficiently to avoid electrical shorting therebetween.
A bracket 130 secures a rod 134 to the frame means such that the rod extends approximately parallel to the axis of the bone proximate the center of the frame where it supports an arcuate mounting bracket 136. Cathode mounting blocks 140 and 150 are secured to the mounting bracket 136 in a conventional way, such as by a bolt and nut arrangement. The block 140 mounts cathodes 142 and 144 preferrable by means of electrically insulative sleeves 146 and 148. In like manner, the block 150 mounts cathodes 152 and 154 by means of sleeves 156 and 158 as will be obvious from the structure illustrated at FIGS. 1 and 2, the position of the cathodes with respect to the pins and the fractured bone by adjustment of the extension of rod 134 from bracket 130, and by movement of the arcuate mounting bracket 136 with respect to the rod 134. Thus, the lateral and axial position of the cathodes may be adjustably varied and subsequently fixed in the desired position.
As pointed out, the specific structures by which the pins and cathodes are mounted are of no consequence insofar as this invention is concerned so long as they perform the necessary function of mounting the pins in fixed relation with the distal ends of the pins secured to the bone to fix the fracture site of the bone and mounting the cathodes with the distal ends of the cathodes in electrical contact with the bone in the proximity of the fracture site. The tips of the pin may be in the fracture site, in the bone adjacent the fracture site or in the soft tissue adjacent the bone fracture site, all of which locations are referred to herein as being in electrical contact with the bone. The cathodes and pins are electrically isolated from each other, except, of course, through the bone and the source of voltage which will be described, such that a voltage can be applied between any cathode and either pair of pins and between the pairs of pins.
The means for applying a voltage is illustrated for the sole purpose of describing the manner in which the voltage is applied. It will be instantly understood that in practice solid state voltage regulators, switches, etc. will be used. Since the exact circuitry and devices for generating and applying a voltage are of no importance to the operation of the invention, so long as the voltage is applied as described, a simplified schematic representation has been selected to more clearly and simply illustrate the voltage applying means.
As shown in FIG. 3, a voltage in a particular cyclical pattern to be described is applied from the voltage applying means 170. Typically, a stable battery having long term constant voltage, indicated at 170, will be used. A current regulator depicted generally at 172 will be included. This, of course, will be a solid state device rather than the functionally schematic variable resister shown. To illustrate the cyclic manner of applying voltage, a pair of wiper switches 174 and 176 driven by motor 178 are shown simply to illustrate that the voltage will be applied sequentially to a number of electrical conductors in cable 180 and thence to the pins 112, 114, 122, and 124, and the cathodes 142, 144, 152 and 154. Again, it is emphasized that solid state switching is conveniently used and that the switching shown is functionally schematic to illustrate the principle. Since solid state circuitry of the type suitable for use in the invention is well known and conventional, and since so many circuits can suitably be used is is deemed unnecessary to describe the same in detail. Reference is made to the aforecited patents for various circuits which may used or modified for use. Reference is also made to standard electronic circuitry texts and manuals.
The operation of the voltage apply means is as follows:
In the preferred embodiment, the apparatus includes four cathodes and two sets of pins. The means for applying electrical voltage applies electrical voltage to the cathodes and the pins cyclically for a a plurality of time periods during each cycle. The cathodes at all times having either no voltage or negative voltage applied thereto. The pins having either positive, negative or no voltage applied thereto, either the first pins or the second pins being positive when a negative voltage is applied to any cathode. The conductors in cable 80 are connected to the switching mechanism such that the voltage application is cycled to cause electron flow from a first cathode to the first pins in a first period, from the first pins to the second pins during a second period, from the second cathode to the second pins in third period, from the second pins to the first pins in fourth period, from the third cathode to the first pins in the fifth period, from the first pins to the second pins in the sixth period, from the fourth cathode to the second pins in the seventh period, and from the second pins to the first pins in the eighth period.
The connection of the conductors between the switching mechanism and the cathodes and pins and the operation of the switching mechanism is fully defined by the following table.
TABLE I______________________________________Time Cathode Polarity Pin PolarityPeriod 112 114 122 124 142 152 144 154______________________________________ -- 0 0 0 + + 0 02 0 0 0 0 - - + +3 0 -- 0 0 0 0 + +4 0 0 0 0 + + - -5 0 0 -- 0 + + 0 06 0 0 0 0 - - + +7 0 0 0 -- 0 0 + +8 0 0 0 0 + + - -______________________________________
Current was controlled in the range of 5 to 20 microamperes. The full sequence of pulsing occurs at 10 Hz timed intervals. Each sequence involves eight events--four firings (negative charging of a cathode) and four discharges of the anodes (pins). Each of these eight events requires 12.5 milliseconds. Thus, the full eight events requires 100 milliseconds and the sequence repeats itself 10 times each second.
It will, of course, be understood that the specific order of voltage application is not critical and can be altered. What is important is that the electron flow be controlled such that it is always from the cathode to one or the other of the sets of pins, when the cathodes are active, and that there be period flow between the pins opposite the direction of flow when the cathode current flows to the pins. The intensity of the current does not differ from that taught in the prior art and may typically range from about 10 microamps to 100 microamps, normally being from 10 to 20 microamps. These ranges are, of course, typical and not critical.
DISCUSSION
Animal studies of the invention were conducted at the Cleveland Research Institute using a canine model. Torsional strength values were almost double for stimulated tibias as compared with a control series. The histological and microradiographic analysis demonstrated earlier evidence of cellular activity (1-2 weeks post operatively) in the stimulated groups. The 6 weeks post operative analysis showed a more dense and more mature material tibial deposit in the stimulated tibial fractures. Significantly, the incidence of pin loosening was only one-fourth as frequent in the stimulated series as in the control series. Additionally the degree of loosening was 3.5 times greater in the control series as in the stimulated series. The level of trace elements in the model was slightly higher in the stimulated series than in the control, but the difference was marginal and the levels for both groups were well within an acceptable range. It was concluded from this series that the invention was both safe and effective in promoting fracture healing in the canine model. Clinical trials are being planned and it is predicted from the animal tests that the invention will be both safe and effective in promoting human bone growth.
It will be understood that considerable variation can be made within the principle of the invention without departing therefrom, especially as regards the structure of the fixation device, the manner of producing the electric voltage for current flow, and the specific order of cycling the voltage to the cathodes and pins.
INDUSTRIAL APPLICATION
This invention will find industrial application in veterinary medicine and in orthopedic surgery. | A combined external fixation and bone growth stimulation apparatus in which current flows, in a defined cycle, from a cathode to one of two pairs of electrodes, then from one pair of electrodes to the other, and then from the cathode to the other pair of electrodes, is disclosed. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to a system and method for controlling a robot. More specifically, the present invention relates to a method of, and system for, tungsten-arc, inert gas (TIG) welding using a programmable industrial robot.
In fusion welding, metals are heated to a temperature at which they melt and are then joined together. Typically, the joint between the metals is formed using a filler metal in the form of a rod or wire. In arc welding, an electric arc is used to melt the metals of interest and the filler metal. Shielded-arc welding is based on the principle of protecting the molten filler metal from atmospheric contamination. In TIG welding, the electrode is protected by an envelope of chemically inert gas, as is shown in the schematic diagram of FIG. 1.
Various automated welding processes have been developed which employ industrial robots. These systems have been developed with feedback control mechanisms which indicate or sense the quality of the weld being made and the position of the welding torch (which is coupled to the robot arm) in relation to the article or articles to be welded.
While feedback control mechanisms have developed to a suitable level for many applications, there is a need for mechanisms and systems which provide for additional control of the welding process, and specifically for control of the welding torch.
As can be seen by reference to FIG. 1, control of the current passing through the tungsten electrode is important to control of the TIG welding process. Sufficient current must be provided to the electrode to create an arc in order to cause the filler wire and workpiece to melt. In addition, certain current levels must be maintained to ensure a uniform melt rate. Further still, current must be turned off when a weld is completed. Thus, a need has developed for an automated arc-welding system that provides more complete and specific control of the electrode current.
Programmable robots used to carry out tasks such as welding use relatively sophisticated computer hardware and software to control the robot and perform high precision, repetitive tasks. Present welding software enables robots to turn on a welding torch, guide the lit torch along a predetermined path, and then turn the torch off. Presently, welding software may be written in a computer language known as RAPID. RAPID software allows operators to select various instructions which correspond to the type of movement desired. Among the instructions available in the RAPID language are the following:
ARCL: This instruction refers to arc welding type welds which are completed in a linear direction. The instruction is used to define weld starts and stops.
ARCC: This instruction refers to arc welding type welds which are completed in a circular direction. To program a circular or curved path, the ARCL instruction is used to select the start point, then the ARCC instruction is used to input arc (i.e. curve) references. The ARCC instruction permits movements to be controlled in half circles.
However, in TIG welding, it is preferred that the welding current in the welding torch be adjusted so that current levels can be ramped up and down as needed. This can be readily accomplished when such welding is done by hand, but suitable welding current control has not yet been achieved in automated systems.
OBJECTS AND SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention to provide a robot control system capable of controlling the current to a current-controlled tool mounted on a robot arm.
A further object of the present invention to is provide a robot control system that provides more complete and specific control of the electrode current in a welding torch.
A further object of the present invention is to provide a robot control system that provides ramping and pulsing control of the electrode current in a welding torch.
These and other objects are achieved in a robot control system that includes a controller, such as a computer, which is capable of accepting operator inputs. An industrial robot is coupled in data communication to the controller. The robot includes a robot arm and a tool such as a welding torch mounted thereon. The tool is controlled in at least one manner by electric current.
The controller is coupled in data communication to a current source and is programmed to control the current supplied to the tool on the robot arm. The programmed controller is capable of receiving inputs from an operator and is capable of ramping the current supplied to the tool from an initial current level to an operator selected current level over an operator defined and inputted selected time. The controller can also ramp the current supplied to the tool from the selected current level to a third, lower current level over a second operator selected and inputted time period. The system also allows an operator to pulse the current supplied to the electrode and to control the rate at which the filler wire is supplied to the welding torch.
Further objects and advantages of the present invention will become more apparent from the following detailed description of the invention taken in combination with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a TIG welding torch.
FIG. 2 is a perspective view of a robot control system including a controller and a robot.
FIG. 3 is a schematic diagram of the robot control system of FIG. 2 and shows a welding feed reel and a current source.
FIG. 4 is schematic diagram showing current ramping carried out by the robot control system of the present invention.
FIG. 5 is a flow chart of the software used in the robot control system of the present invention.
FIG. 6 is a simplified, schematic flow chart showing the structure of the software used in the robot control system of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 2, there is shown an articulated arm robot 10 having an arm 11 and a base 12. At one end of the arm 11 is a TIG welding torch 14 having an electrode 15. The arm 10 includes a sufficient number of segments 23, pivotally connected together by a sufficient number of pivotable connections, to permit the torch 14 to have six degrees of freedom of movement. Using feedback mechanisms, such as transducers (not shown), the relative angle between adjacent segments is measured. The transducers continuously send signals representing the angles to a data processing means or controller 22, which may be located in or otherwise connected, for example, by cable 23, in data communication to the robot 10. The controller 22 uses this angle information to arrive at the spatial location of the torch 14. The robot 10 may be installed at a fixed table installation 25 where a workpiece 26 may be welded.
As best seen by reference to FIGS. 2 and 3, the controller 22 may take the form of a programmable computer or other arrangement based upon a microprocessor. The controller 22 includes an internal central processing unit or data processor 27, a screen 28 on which a menu of information (e.g., a graphic user interface) may be displayed and selected from, and an input means such as a teach pendant 30, keyboard 32, or both. The controller 22 will generally include some means for storing information to a movable storage media, such as a floppy disk drive 34.
The controller 22 is coupled in data communication to an electric source 40 via a cable 42. The electric source 40 is coupled to the workpiece 26 through cable 44 and supplies current to the electrode 15 through cable 46. A welding feed reel 47 supplies a welding or filler wire 50 to the welding torch 16.
The controller may receive information from a feed back mechanism such as a through-the-arc seam tracker 50. The seam tracker 50 is designed to monitor a weld as it is made by the welding torch 16 and relays information regarding the weld to the controller 22 through a communication cable (not shown).
The robot 10 may be programmed to follow a predetermined path, such as a welding path, by loading an appropriate program into the controller 22. Such a welding program includes instructions describing the overall welding path, weld starts, stops, and other movements of the robot. Welding path programs may be created using a variety of methods and be written in a variety of computer programs. One method of creating an appropriate program is to write them in the language RAPID. More specifically, each of the instructions is designed to be used in connection with ARCWARE software. Some familiarity with the RAPID computer language and ARCWARE software is assumed in the discussion that follows. Background information on the RAPID language and ARCWARE software may be obtained from various commercial sources including ABB Flexible Automation, Inc., Fort Collins, Colo., and specifically by reference to the RAPID Reference Manual, Article No.: 3HB 5815-1, which is hereby incorporated by reference.
As noted, present welding software allows operators to select various instructions which correspond to types of movements. The present invention provides improved programming capability through new programming instructions. The first of these instructions is the TIGL instruction. This instruction is used to carry out TIG welding type welds which are completed in a linear direction. The instruction is used to control and monitor the entire TIG welding process by moving the tool center point (TCP) in a linear path to a specified destination. All phases, such as weld start, weld end, and ramping of the weld current are controlled, and the welding process is monitored continuously. A feed back mechanism such as a through the arc seam tracker may be used to monitor the welding process. The TIGL instruction includes many arguments and may be defined as follows:
TIGL \On! \Off! pToPoint nRampTime vTigSpeed \nTime! smTigSeam wdTigWeld wvTigWeave zTigZone \nZone! tTigTool \obTigWobj!.
Each of the listed arguments may be defined as follows.
\On! Data type: switch
This optional argument is normally used in the first instruction of a tig weld. It turns on the tig welder and if the nRampTime argument is greater than zero, it ramps the weld current up to a specified value as described below in the wdTigWeld argument.
\Off! Data type: switch
This optional argument is used to finish a weld and turn off the tig welder. If theTigL\Off nRampTime argument is greater than zero, TigL\Off ramps the weld current down to a specified value as described below further in the smTigSeam argument.
pToPoint Data type:robtarget
The destination point of the robot and external axes, either defined as a named position (robtarget) or stored directly in the instruction.
nRampTime Data type:num
This argument controls the duration (time in seconds) of the weld current ramp, either a ramp up if TigL\On is used, or a ramp down if TigL\Off is used. If zero is entered in the argument, there will be no weld current ramp.
vTigSpeed Data type:speeddata
vTigSpeed controls the speed of the TCP when the robot tool, i.e. the welding torch, is not welding or moving point to point through TIG welding type welds.
\nTime! Data type:num
nTime is used to specify the total time of movement in seconds directly in the TigL instruction.
smTigSeam Data type:seamdata
smTigSeam describes the start and end phases of the tig welding process.
When the TigL\On instruction is used, the starting value of the weld current up ramp is entered in seam data component: ign -- voltage. When the TigL\Off instruction is used, the seam data component fill -- voltage value is used as the ending value of the weld current down ramp.
wdTigWeld Data type:welddata
wdTigWeld describes the weld phase of the tig welding process. When the TigL\On instruction is used, the weld current is ramped up after ignition, from the initial value entered in the seamdata argument (ign -- voltage) to the main welding current value which is entered in the welddata component: weld -- voltage. When the TigL\Off instruction is used, the weld current is ramped down, from the main welding current value which is entered in the welddata component: weld -- voltage, to the final current value which is entered in the seamdata component: fill -- voltage.
wvTigWeave Data type:weavedata
wdTigWeave describes the weaving that will take place during the welding phase.
zTigZone Data type:zonedata
wdTigZone defines in millimeters how close the axes must be to the programmed position before they can start moving towards the next position.
Weld data changes over to the next welding instruction at the center point of the corner path (if not delayed by the delay -- distance component in the wdTigWeld argument).
\nZone! Data type:num
This argument is used to specify the positional accuracy of the robot's TCP directly in the TigL instruction. The size of the zone is specified in millimeters and is substituted in the corresponding zone specified in zTigZone. The \nZone argument is useful when trimming individual corner paths.
tTigTool Data type:tooldata
tTigTool is used in the robot's movements. The TCP of the tool is the point moved to the specified destination position (pToPoint).
\obTigWobj! Data type:wobjdata
The work object (coordinate system) that the robot's movements are referenced to is specified in the obTigWobj. When this argument is omitted, the robot position is referenced to the world coordinate system. This argument must be specified if a stationary TCP or coordinated external axes are used.
An example of appropriate code for carrying out a linear TIG weld is as shown below.
PERS welddata wdTig1:= 10,150,30,0,0,150,18!;
PERS welddata wdTig2:= 8,100,12,0,0,0,0!;
PERS seamdata smTig1:= 1,0.5,50,0,0,0,0,0,0,0,0,0,1,50,0!;
PERS weavedata NoWeave:= 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0!;
PERS weavedata wvTig1:= 1,0,0.1,0.1,0,0,0,0,0,0,0,0,0,0,0!;
MoveJ. . .
TigL\On,p 1,3,v300,smTig1,wdTig1,NoWeave,fine,tWeldGun\obTigWobj:=wobjside1;
TigLp2,0,v300, smTig1,wdTigL1,NoWeave,fine,tWeldGun\obTig Wobj:=wobjside1;
TigLp3,0,v300,smTigL1,wdTig2,wvTigL1,fine,tWeldGun\obTigWobj:=wobjside1;
TigL\Off,p4,2,v800,smTigL1,wdTig1,NoWeave,fine,tWeldGun.backslash.obTigWobj:=wobjside1;
In the example, the robot executes a joint move moving the torch or welder to a pre-weld position. A joint move is a linear movement by the robot to a desired point where the quickest path in each axis is followed to reach the point. The robot then moves the welder to the starting position of the weld, p1, at a speed of v300 (or 300 mm/s). At p1 the gas solenoid and the TIG welding gun are turned on. The starting value of the weld current is 50 amps as entered in the smTigL1 ign -- voltage component. When the TIG arc is established, the TIG weld current is ramped up to 150 amps (as specified in the wdTig 1 weld -- voltage component) in 3 seconds. Ramping up the current is accomplished in a series of discrete steps. A change is made every 100 ms and the amplitude of the change is based on the time of the ramp and the difference between the ignition voltage and the weld voltage. The stepping up of the voltage (and, therefore, the current) approximates a straight line ramp. (See FIG. 4) The ramping up of the current in discrete steps is refered to as step-wise ramping. After the current is ramped up, the welding feed reel is then turned on, and the robot moves the welder to p2.
At p2 the weld current is changed (no ramp) to 100 amps (as specified in the wdTig2 weld -- voltage component) and the robot begins weaving as specified in wvTigL1 and moves to p3. At p3 the weld current is changed (no ramp) to 150 amps (as specified in the wdTigL1 weld -- voltage component), weaving is stopped, and the robot moves the torch to p4. At p4 the wire feeder is turned off, the weld current is ramped down to 50 amps (as specified in the smTigL1 fill -- voltage component) in 2 seconds, and the welder is turned off. Ramping down occurs in a similar fashion as ramping up, except the amplitude of each decreasing step is based on the time of the ramp and the difference between the weld voltage and the fill or ending voltage.
So that welds may be performed along curved paths, the present invention provides a second instruction, TIGC. The TIGC instruction is used to weld along a circular path. Using the TIGC instruction the TCP may be moved in a circle to a specified destination. All phases, such as weld start, weld end, and ramping of the weld current are controllable, and the welding process is monitored continuously. The instruction may be defined as follows:
TigC \On! | \Off! pCirclePt pToPoint nRampTime vTigSpeed \nTime! smTigseam wdTigWeld wvTigWeave zTigZone \nZone! tTigTool \obTigwobj!.
The arguments in the instruction are defined as follows:
\On! Data type:switch
This optional argument \On is normally used in the first instruction of a tig weld.
It turns on the tig welder and if the nRampTime argument is greater than zero, it ramps the weld current up to a specified value as described below in the wdTigWeld argument.
\Off! Data type: switch
This optional argument \Off is used to finish a weld and turn off the tig welder. If the TigC\Off nRampTime argument is greater than zero, TigC\Off ramps the weld current down to a specified value as described below in the smTigSeam argument.
pCirclePt Data type:robtarget
The circle point is a radius position on the circle between the start point and the destination point of the robot and external axes. To obtain the best accuracy, this point should be about halfway between the start and the destination points. If chosen to close to the start point or destination point, the robot may give a warning. The circle point is defined as a named position or stored directly in the instruction (marked with an * in the instruction).
pToPoint Data type:robtarget
This is the destination point of the robot and external axes, and is either defined as a named position (robtarget) or stored directly in the instruction.
nRampTime Data type:num
This argument controls the duration (time in seconds) of the weld current ramp, either a ramp up if TigC\On is used, or a ramp down if TigC\Off is used. If zero is entered in the argument, there will be no weld current ramp.
vTigSpeed Data type:speeddata
vTigSpeed controls the speed of the TCP when the welder or torch is not welding or moving point to point through welding positions.
\nTime! Data type:num
nTime is used to specify the total time of movement in seconds directly in the TigC instruction.
smTigSeam Data type:seamdata
smTigSeam describes the start and end phases of the tig welding process. When the TigC\On instruction is used, the starting value of the weld current up ramp is entered in seam data component: ign -- voltage. When the TigC\Off instruction is used, the seam data component fill -- voltage value is used as the ending value of the weld current down ramp.
wdTigWeld Data type:welddata
wdTigWeld describes the weld phase of the tig welding process. When the TigC\On instruction is used, the weld current is ramped up after ignition, from the initial value entered in the seamdata argument (ign -- voltage) to the main welding current value which is entered in the welddata component: weld-voltage. When the TigC\Off instruction is used, the weld current is ramped down, from the main welding current value which is entered in the welddata component: weld -- voltage, to the final current value which is entered in the seamdata component: fill -- voltage.
wvTigWeave Data type:weavedata
wdTigWeave describes the weaving that will take place during the welding phase.
zTigZone Data type:zonedata
wdTigZone defines in millimeters how close the axes must be to the programmed position before they can start moving towards the next position. Weld data changes over to the next welding instruction at the center point of the corner path (if not delayed by the delay -- distance component in the wdTigWeld argument).
\nZone! Datatype:num
This argument is used to specify the positional accuracy of the robot's TCP directly in the TigC instruction. The size of the zone is specified in millimeters and is thus substituted in the corresponding zone specified in zTigZone. The \nZone argument is useful when trimming individual corner paths.
tTigTool Data type:tooldata
tTigTool is used in the robot's movements. The TCP of the tool is the point moved to the specified destination position (pToPoint).
\obTigWobj! Data type:wobjdata
The work object (coordinate system) that the robot's movements are referenced to is specified in the obTigWobj. When this argument is omitted, the robot position is referenced to the world coordinate system. This argument must be specified if a stationary TCP or coordinated external axes are used.
An example of appropriate code for carrying out a curved TIG weld is shown below.
PERS welddata WdTigL:= 10,150,30,0,0,150,18!;
PERS welddata wdTig2:= 8,100,12,0,0,0,0!;
PERS seamdata smTig1:= 1,0.5,50,0,0,0,0,0,0,0,0,0,1,50,0,!;
PERS weavedata NoWeave:= 0,0,0,0,0,0,0,0,0,0,0,0,0!;
PERS weavedata wvTig1:= 1,0,0.1,0.1,0,0,0,0,0,0,0,0,0,0!;
MoveJ. . .
TigL\On,p1,3,v300,smTig1,wdTig1,NoWeave,fine,tWeldGun\obTigWobj:=wobjside 1;
TigC p2,p3,0,v300,smTig1,wdTig1,NoWeave,fine,tWeldGun\obTigWobj:=wobjside;
TigC\Off,p4 ,p5,2,v800,smTig1,wdTig1,wvTig1,NoWeave, fine,tWeldGun\obTigWobj:=wobjside;
In this example, the robot executes a joint move to a pre-weld position. It then moves to the starting position of the weld, p1, at a speed of v300. At p1 the gas solenoid and the welding torch are turned on. The starting value of weld current is 50 amps as entered in the smTigL1 ign -- voltage component. When the tig arc is established, tig weld current is ramped up to 150 amps (as specified in the wdTigL1 weld -- voltage component) in 3 seconds. The welding feed reel is then turned on, and the robot moves in an arc from p1 to p3 via circle point p2.
At p3 the weld current is changed (no ramp) to 100 amps (as specified in the wdTig2 weld -- voltage component) and the robot begins weaving as specified in wvTigL1 and moves in an arc from p3 to p5 via circle point p4 . At p5 the wire feeder is turned off, the weld current is ramped down to 50 amps (as specified in the smTigL1 fill -- voltage component) in 2 seconds and then the welder is turned off.
The TIGL and TIGC instructions make internal calls to existing instructions ARCL and ARCC, respectively. When calling these latter instructions, TIGL and TIGC pass on all received arguments and, therefore, each has all the associated features of ARCWARE software such as weld and weave tuning, wire jogging, weld and weave blocking, weld restart, and fault management. The TIGL and TIGC instructions are considered to be a part of a software module which the inventors have named TIGWARE. The code for the TIGWARE module is set out in the attached program listing in Exhibit A and may be understood by reference to FIGS. 4, 5, and 6.
The TIGWARE module provides for pulsing of the current supplied to the electrode through the PulseOn, Pulse, and PulseOff procedures which are set out in pages 2-4 in the attached program listing. These three procedures also provide for control over the rate at which the filler wire is provided to the welding torch 14.
As best seen in FIG. 4, the amplitude of the current supplied to the electrode may be varied, if desired, in order to carry out specific types of TIG welds. The current may be supplied as a square wave or other periodic wave. The amplitude may be varied from a background current level to a peak level, and if desired the rate at which the filler wire is fed to the welding torch 14 may be adjusted to correspond to the current pulsing, with a high feed rate being used at high current amplitude and a low current rate at a low current amplitude.
While the present invention has been described in what is believed to be the most preferred form, it is to be understood that the invention is not confined to the particular construction and arrangement of the components herein illustrated and described, but embraces such modified forms thereof as come within the scope of the following claims. In particular, the scope of the present invention is not intended to be limited to welding applications. Various other uses of the present invention may be made in plasma welding, plasma cutting, oxy-fuel cutting, laser cutting, laser welding, painting, sanding, cleaning, assembling, and other actions where ramping and control of current is useful. Specifically, for example, instructions could be developed using the RAPID software language and implemented in the present invention to program a desired painting path using current to control the operation of a painting gun. | A robot control system that includes a controller that is capable of controlling the current supplied to a current-controlled tool mounted on the robot. The controller is capable of accepting operator inputs and the robot is coupled in data communication to the controller. A tool which is controlled in at least one manner by electric current is mounted on the arm of the robot. The controller is coupled in data communication to a current source and is programmed to control the current supplied to the tool. The controller is also capable of receiving inputs from an operator and is capable of ramping the current supplied to the tool from an initial current level to an operator selected current level over an operator defined and inputted selected time. The controller can also ramp the current supplied to the tool from the selected current level to a third current level over a second operator selected and inputted time period. | 1 |
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The invention is directed to a closing cylinder with a cylinder core for insertion of a key for resetting closing followers in the cylinder core from their blocking engagement in a bearing sleeve. The there provided overload blocker is to protect the closing cylinder against damages, in case unauthorized persons perform forced rotations at the cylinder core by way of a break-in tool. The overload blocker responds to a certain limiting torque. In a normal case, at a rotation of the cylinder core by way of a proper key, the torque is transferred to a drive member of the closing cylinder, which drive member performs the desired functions at the vehicle. If however the limiting torque has been surpassed by forced rotations without key, then the overload blocker passes into an overload case, where the torque does not pass to the driven member of the closing cylinder based on internal decoupling. Then no function is performed in the vehicle. The cylinder core together with the bearing sleeve fixed against rotation relative to the cylinder core is idle running.
(2) Description of Related Art including information disclosed under 37 CFR 1.97 and 1.98
The German patent document DE 38 27418 C2 shows such a closing cylinder. Here the overload blocker comprises a release sleeve with a sliding claw connected in fact axially fixed but rotatable to the release sleeve. The sliding claw has a coupling part, which engages a counter coupling part of the closing cylinder based on a spring force. Profiled locking cams and counter profiled locking recesses are disposed between the release sleeve and a bearing sleeve, wherein the release sleeve is shifted parallel between its normal position and its overload position through the locking recesses. A helical spring encloses a core piece of the driven member and of the sliding claw and takes care of a pressure on all sides between an inner flange of the release sleeve and an outer flange of the sliding claw. Also the sliding claw is shifted parallel thereby during a transition from the normal case to the overload case.
The locking cams effective for decoupling the carrier relative to the closing cylinder and the locking recesses between the release member and the bearing sleeve have to be kept small for reasons of space limitations in the known closing cylinder. Therefore various different limiting torques result with a production of the known closing cylinder. The straying of these values makes it more difficult to furnish a guarantee relative to the functional security of the closing cylinder.
BRIEF SUMMARY OF THE INVENTION
1. Purposes of the Invention
It is an object of the present invention to develop a function secured closing cylinder, wherein the overload blocker of the closing cylinder is improved. This is achieved by the following features, which have the following particular importance.
2. Brief Description of the Invention
The invention employs a release lever, which release lever is swivel supported at its one circumferential position in the cylinder casing, as a release member. The release lever transitions in an axial plane between two swivel positions upon the transition between the normal case and the overload case. The release lever is combined with the carrier to a swivel unit capable of a common swivel motion. The locking cam or, respectively, the locking recess is disposed at a circumferential position, which circumferential position is disposed opposite to the swivel bearing position of the release lever. The swivel bearing position is kept spatially fixed during the transition between the normal case and the overload case, and for that reason more space remains at the oppositely disposed circumferential position. Therefore in case of a predetermined available space in the closing cylinder, the axial height of the locking cam and of the locking recess can be formed larger as with the known, parallel shiftable release member. Based on the larger formation, the production tolerances play a lesser role. Therefore the limiting torque is nearly constant in the context of the present invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
Further features and advantages of the invention result from the further claims, the following description and the drawings. An embodiment example of the invention is presented in the drawings. There is shown in:
FIG. 1 is a partial longitudinal section of the closing cylinder of the present invention in the normal case of the overload blocker,
FIG. 2 is the longitudinal sectional view of the closing cylinder analogous to FIG. 1 in the overload case of the overload blocker,
FIG. 3 is a perspective explosive view showing the components of the closing cylinder of FIGS. 1 and 2 with a view onto the outer front end of the cylinder core, where only one-half of the cylinder casing is shown,
FIG. 4 is a perspective explosive view of the components analogous to the view of FIG. 3 , however with a view onto the inner end of the device group,
FIG. 5 is a perspective view of the device components of the closing cylinder shown in FIG. 1 , wherein the cylinder casing of the closing cylinder is longitudinally subdivided into two casing shells, of which shells one was dispensed with, and
FIG. 6 is a perspective view analogous to FIG. 5 , where the two casing shells of the cylinder casing are connected to each other.
DETAILED DESCRIPTION OF THE INVENTION
The closing cylinder comprises initially a cylinder core 10 , which includes a key guide 12 for the insertion of a key not shown in detail. The cylinder core 10 comprises chambers for closing followers not shown in detail, which normally stand in a blocking engagement with a bearing sleeve 20 . The cylinder core 10 is rotatably supported in the bearing sleeve 20 . The lever tumblers are set back through the inserted key, wherewith the cylinder core 10 can be rotated in the bearing sleeve 20 by way of the key.
The bearing sleeve 20 is supported axially fixed and rotatable in a cylinder housing 30 , wherein the cylinder housing 30 comprises two housing shells 31 , 32 . In a normal case however, the bearing sleeve 20 rotatable in the cylinder housing 30 is fixed against rotation through an overload blocker 25 , so long as a torque is exerted onto the cylinder core, where the torque is situated below a predetermined limiting torque. The components of such an overload blocker 25 can be best recognized from FIG. 4 and they comprise the following device components.
The overload blocker 25 comprises initially a release member, which is formed as a release lever 40 in the context of the present invention. The release member namely is pivotably supported at a circumferential position at 42 in the cylinder housing 30 , as is shown in FIGS. 1 and 2 . The release member has a locking cam 41 disposed opposite to this swivel bearing position 42 , wherein the locking cam 41 tends to engage a snap in recess 21 at the inner front end 22 of the bearing sleeve 20 based on an axial spring loading 16 directed in the direction of the dash-dotted longitudinal axis 13 . The release lever 40 is always non-rotatable positioned in the bearing housing 30 in the way to be described in more detail, therefore also the bearing sleeve 20 is non-rotatable in the normal case by the engagement of the locking cam 41 in the snap in recess 21 .
In the normal case, where the overload blocker 25 is effective, therefore a rotation of the inserted key can be transferred from the cylinder core 10 to a driven member 35 , which driven member 35 is rotatably supported at the inner end of the housing 30 as shown in FIGS. 1 and 2 . A rotation of the driven member 35 is transferred over the shaft 36 connected to the driven member 35 to a function member in the vehicle, for example a vehicle lock in order to perform there the desired functioning in the vehicle.
The cylinder core 10 has a staggered cylinder inner end 14 best recognizable from FIG. 4 for the transition of the rotation, which cylinder inner end 14 is coupled to a carrier 50 in the normal case. This coupling comprises a coupling part 51 , wherein the coupling part 51 is engaged with a counter coupling part 11 of the cylinder core 10 in a normal case. The coupling part is formed by a radial projection 51 according to the embodiment example of the invention, wherein the radial projection 51 points into the interior 52 of the ring of the carrier 50 formed here as a circular ring as can be best recognized from FIG. 3 . The counter coupling part comprises an axial groove 11 in the staggered cylinder inner end 14 as can be recognized best from FIG. 4 . The carrier 50 rests at the release lever 40 , wherein the release lever 40 itself is formed as a circular ring. The circular ring of the carrier 50 has initially an axial flange 53 directed toward the outside as can be best recognized from FIG. 3 , wherein the axial flange 53 in the mounted case rests at the circular ring from the release lever 40 , as is shown in FIGS. 1 and 2 . A radial collar 54 also exists at the axial flange 53 of the carrier 50 , of the circular release lever recognizable from FIG. 3 .
The rotation of the carrier 50 effected by the rotation of the key in a normal case is transferred to the driven member 35 through two connection means 57 , 37 standing always in engagement to each other. The carrier 50 has three webs 57 disposed parallel to the longitudinal axis 13 as a first connection means, wherein the webs 57 project at the inner front face from the annular body of the carrier 50 . The second connection means comprise holes 37 running parallel to the axis in the driven member 35 as shown in FIG. 3 . The webs 57 engage in the holes 37 of the driven member 35 not only in the normal case, but also in the overload case in the present situation.
The driven member 35 strives to pass into a defined zero position relative to the cylinder housing 30 by way of a so-called pulse spring 26 , which can be recognized in FIGS. 1 and 2 . For this purpose the pulse spring 26 has two legs 27 , 28 , which legs grip between themselves on the one hand an axial finger 38 of the driven member 35 and on the other hand a web 33 recognizable best in FIG. 6 . After rotation of the key, which is only possible in the normal case, therefore the driven member moves back again into its starting rotary position and thereby takes also the cylinder core 10 into a corresponding zero position.
The hook piece 44 radially grips around the circular ring of the carrier 50 in the circumferential region and grips behind the circular ring in the assembly situation at its inner front face 56 as shown in FIG. 1 . Thus there is generated from the release lever 40 and the carrier 50 a common swivel movable unit 55 . However, the carrier 50 is rotatable relative to the release lever 40 in this swivel unit 55 as was mentioned above.
The release lever 40 and therewith the complete swivel unit 55 is held in a first swivel position in a normal case as recognizable from FIG. 1 , wherein the first swivel position is marked by an auxiliary line 40 . 1 . Then the already recited coupling between the locking cam 41 and the snap in recess 21 is present. This first swivel position can therefore be designated as “coupling swivel position”. A connection fixed in axial direction exists between the release lever 40 and the carrier 50 , wherein the connection fixed in axial direction consists of a hook piece 44 .
The swivel axis 45 disposed at the swivel bearing position 42 is placed perpendicular to the release lever 40 and at a radial distance from the longitudinal axis 13 of the closing cylinder as is shown FIGS. 1 and 2 . A bearing piece 46 is inserted in a radial sparing 34 of the cylinder housing 30 and serves for swivel support. The incorporation position of the bearing piece 46 is secured in the sparing 34 by the circumferential face of the bearing sleeve 20 as is shown in FIGS. 1 and 2 . This alleviates the assembly of the closing cylinder according to the present invention.
In addition to the already recited locking cam 41 also a guide piece 48 is disposed opposite to the swivel bearing position 42 that is at the free arm end 47 of the release lever 40 shown in FIG. 4 . This guide piece 48 engages into an inner recess 39 of the cylinder housing 30 in the assembly case recognizable in FIGS. 1 and 2 . The guide piece 48 and the housing recess 39 take care of swivel guiding during swiveling of the release lever 40 . The already recited fixed against rotation, but swivel movable guiding of the release lever 40 is obtained in the cylinder housing 30 both through the guide please 48 as well as through the swivel axis 45 at the bearing piece 46 .
The previously described axial spring loading 16 attacks only at the arm end 47 of the release lever 40 . For this purpose serves a pressure spring 15 , which according to FIG. 1 is disposed in the previously recited inner recess 39 in the housing 30 . The pressure spring 15 is supported on the one hand at the inner axial end of the recess 39 in the housing 30 and on the other hand at the support position 17 at the free end 47 of the arm of the release lever 40 as can be best seen in FIG. 4 . This support position 17 is integrated into the previously recited guide piece 48 . There a receptacle 18 is placed as shown in FIG. 4 , which receptacle 18 receives at least a part piece of the pressure spring 15 . The receiver 18 can continue in part also in the hook piece 44 . The guide piece 48 is a nose, which is disposed in the circumferential region of the annular body of the release lever 40 and which projects perpendicular to a certain lever plane determined by the annular body of the release lever 40 . The locking cam 41 is formed also at a nose generated by the guide piece 48 , wherein the locking cam 41 belongs to the overload blocker. The hook piece 44 is also disposed in the region of the nose, however the hook piece 44 runs in an opposite direction to the locking cam 41 .
An overload case is present were a torque is exerted on the cylinder core through break in tools and the like, wherein said torque amounts to more than the above recited limiting torque. The locking cam 41 and/or the locking recess 21 are in fact axially profiled, whereby run on bevels are generated between them. If the key is not plugged into the cylinder core, then the closing followers not shown in detail in the cylinder core 10 are engaged with the blocking grooves of the bearing sleeve 20 . Then the cylinder core 10 is connected to the bearing sleeve 20 fixed against rotation, whereby the two device components 10 , 20 are rotated together in the cylinder housing 30 with the break-in tools. Here the run on inclinations take care that the locking cam 41 becomes pressed out of the locking recess 21 against the spring loading 16 . The free end 47 of the arm of the release lever 40 is transferred from a coupling swivel position 40 . 1 of FIG. 1 into a second swivel position 40 . 2 in FIG. 2 illustrated by the auxiliary line 40 . 2 , since the release lever 40 with its locking cam 41 is moved over the run on inclinations of the locking recess 21 of the bearing sleeve 20 . The second swivel position 40 . 2 therefore is the decoupling swivel position of the release lever 40 .
The carrier 50 is given together in the decoupling swivel position 40 . 2 because of the swivel unit 55 , with the consequence that the coupling 51 of the carrier 50 is decoupled off the counter coupling part 11 of the cylinder part 10 . Therefore, a forced rotation of the cylinder core 10 in case of overload cannot any longer be transferred over the carrier 50 onto the driven member 35 . In face of an overload the cylinder core rotates and the therewith fixed against rotation, bearing sleeve 20 in an idle motion relative to the decoupled swivel unit 55 . The driven member 35 remains in a rest position. No functions in the vehicle can be triggered by the forced rotation of the cylinder core.
The angle of the key rotation of the cylinder core 10 is limited by limit stops 23 , 24 at the driven member 35 in the present case, which can be recognized in FIG. 3 . These limit stops 23 , 24 are formed by the inner shoulders of a radial cutout 29 in a circumferential region of the driven member 35 . An axial extension arm 19 is coordinated to this cutout 29 as can be recognized in FIG. 4 , wherein the axial extension arm is seated at the housing 30 . The inner radial recess 39 of the housing 30 for the guide piece 48 is disposed in part below the axial extension arm 19 .
LIST OF REFERENCE CHARACTERS
10 cylinder core
11 counter coupling part; axial groove in 13 ( FIG. 4 )
12 key guide ( FIG. 3 )
13 longitudinal axis
14 inner end of cylinder of 10 (FIGS. 3 , 4 )
15 pressure spring of 25 ( FIG. 4 )
16 elastic force of 40 , 55 , spring loading ( FIG. 2 )
17 support position for 15 ( FIG. 4 )
18 receiver for 15 in 48 ( FIG. 4 )
19 axial extension arm at 30 ( FIG. 4 )
20 bearing sleeve
21 snap in recess in 20
22 inner front end of 20 ( FIG. 4 )
23 first limit stop of 35 for 19 ( FIG. 3 )
24 second limit stop of 35 for 19 ( FIG. 3 )
25 overload blocker ( FIG. 4 )
26 pulse spring for 35
27 first leg of 26
28 second leg of 26
29 radial cutout in 25 ( FIG. 3 )
30 cylinder housing
31 first housing shell of 30
32 second housing shell of 30 ( FIG. 6 )
33 axial web at 30 ( FIG. 6 )
34 sparing for 46 in 30 (FIGS. 1 , 2 )
35 driven member
36 shaft at 35 (FIGS. 1 , 2 )
37 second connecting means at 35 , hole ( FIG. 3 )
38 axial finger at 35 for 27 , 28 (FIGS. 1 , 6 )
39 inner recess in 30 for 48 (FIGS. 1 , 2 )
40 release lever
40 . 1 coupling swivel position of 40
40 . 2 decoupling swivel position of 40
41 locking cam at 40
42 first circumferential position of 40 , swivel bearing position
43 anullar opening in 40 ( FIG. 3 )
44 hook piece at 40 ( FIG. 4 )
45 swivel axis between 42 , 40 (FIGS. 1 , 2 , 4 )
46 bearing piece 44 (FIGS. 1 , 2 , 4 )
47 free arm end of 40 (FIGS. 2 , 4 )
48 guide piece at 40 (FIGS. 1 , 2 , 4 )
50 carrier
51 coupling part, radial projection
52 ring interior of 50 , ring opening ( FIG. 3 )
53 axial flange of 50 ( FIG. 3 )
54 radial collar of 50 ( FIG. 3 )
55 swivel unit out all 40 , 50 (FIGS. 1 , 2 )
56 inner front face of 50 (FIGS. 1 , 4 )
57 first connecting means at 50 , web | In order to enable a turning of a key of a lock cylinder onto a driven member (shaft 36 ) in the lock cylinder only when a proper key is inserted, yet to prohibit the turning in case of an overload, an overload lock is arranged therebetween. The driven member (shaft 36 ) should specifically actuate functions in the vehicle only if the correct key is used. A threshold rotation torque determines the change between the normal and the overload state. In order to improve the lock cylinder, it is furnished that a disengaging lever ( 40 ) is mounted in the cylinder housing ( 30 ) in a pivotable manner ( 42 ) and can be displaced between two pivot positions in a radial plane defined by the longitudinal axis ( 13 ) of the lock cylinder. A locking cam ( 41 ) belonging to the overload lock is arranged on the free end of the disengaging lever ( 40 ). When the disengaging lever pivots, a carrier ( 50 ) pivots in unison, the carrier having a coupling part which engages in a counter coupling part of the cylinder core ( 10 ) during normal function. The disengaging lever ( 40 ) and the carrier ( 50 ) form a common pivot unit. In case of overload, wherein a rotation of the cylinder core force, the carrier ( 50 ) is decoupled from the cylinder core ( 10 ). | 8 |
[0001] This application claims the benefit of Taiwan Patent Application Serial No. 102123170 filed on Jun. 28, 2013, the subject matter of which is incorporated herein by reference.
BACKGROUND OF INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a driving switching system applied to motors, and more particularly to the driving switching system for motors that can base on the first kickback voltage and the second kickback voltage to determine the switching among various MOSFETs to drive the motor, as preset threshold voltages are reached.
[0004] 2. Description of the Prior Art
[0005] The motor is one of the popular mechanic parts in normal life. In driving circuit of the conventional motor, the H-bridge circuit and the driving module are two important elements. Generally, the H-bridge circuit includes two P-type Metal-Oxide-Semiconductor Field-Effect Transistors (PMOSFETs) and two N-type Metal-Oxide-Semiconductor Field-Effect Transistors (NMOSFETs). In structuring, a pair of one PMOSFET and one NMOSFET in series is electrically coupled with another pair of PMOSFET and NMOSFET in series through a coil, in which the two PMOSFETs are electrically connected to the source power VDD, while the two NMOSFET are electrically connected to the ground VSS. The driving module is electrically connected the aforesaid two PMOSFETs and the aforesaid two NMOSFETs.
[0006] In the art, the H-bridge circuit is to drive the motor. As the H-bridge circuit drives the motor, it may meet a situation that the current is terminated during the commutation of the motor; such that two ends of the coil (one at the PMOSFET and another at the NMOSFET) would generate a kickback voltage. Sometimes, the kickback voltage may be higher than the source power VDD or lower than the ground VSS. As an ill consequence, the aforesaid PMOSFETs and NMOSFETs may be damaged, and further the motor may be degraded or even shutdown.
[0007] Further, for the nature of the PMOSFET and the NMOSFET, the parasitic diodes may extend the tolerance of the kickback voltage (for example, from VDD+Vd to VSS−Vd). However, in practice, the formation of the kickback voltage usually interferes the driving of the motor or leads to the damage of the IC through the CMOS latch-up phenomenon.
[0008] It is clearly that the kickback voltage would damage the PMOSFET and the NMOSFET in the motor's driving circuit, and would dysfunction the motor to some degree. Further, the induced latch-up effect would also damage the IC. Hence, it is definitely welcome to the art to an effort in improving the motor's driving circuit to act against the kickback voltage.
SUMMARY OF THE INVENTION
[0009] Accordingly, it is the primary object of the present invention to provide a driving switching system applied to motors, in which the damage caused by the kickback voltage can be reduced by switching the in-current MOSFETs based on the kickback voltage across the coil.
[0010] In the present invention, the driving switching system includes an H-bridge circuit, at least a kickback voltage detection module and at least a driving module. The H-bridge circuit includes a first PMOSFET, a first NMOSFET, a second PMOSFET and a second NMOSFET. The first NMOSFET connects with the first PMOSFET to have a first connection terminal, and the second NMOSFET connects with the second PMOSFET to have a second connection terminal, in which both the terminals are connected to at least a coil.
[0011] The kickback voltage detection module preset with a first threshold voltage and a second threshold voltage connects electrically with the first connection terminal and the second connection terminal, and is used to detect a first kickback voltage at the first connection terminal and a second kickback voltage at the second connection terminal. Based on the first kickback voltage and the second kickback voltage, the kickback voltage detection module can issue a detection signal. The driving module coupled electrically with the kickback voltage detection module is to receive the detection signal. During a first switch stage, a second switch stage and a third switch stage, the motor is driven by switching on/off the first PMOSFET, the second PMOSFET, the first NMOSFET and the second NMOSFET, respectively.
[0012] While in the first switch stage, the driving module turns off the first PMOSFET and, as the first kickback voltage reaches the first threshold voltage, the kickback voltage detection module issues the detection signal to the driving module and the first NMOSFET is turned on so as to have a first residual current of the coil to flow through the first NMOSFET, the coil and the second NMOSFET.
[0013] While in the second switch stage, the driving module turns off the second NMOSFET and, as the second kickback voltage reaches the second threshold voltage, the kickback voltage detection module issues the detection signal to the driving module and the second PMOSFET is turned on. Further, as the first kickback voltage reaches the first threshold voltage, the kickback voltage detection module issues the detection signal to the driving module, the first PMOSFET is turned on and, on the other hand, the first NMOSFET is forced to turn off so as to have a second residual current to flow through the first PMOSFET, the coil and the second PMOSFET.
[0014] While in the third switch stage, the driving module turns off the second PMOSFET and, as the second kickback voltage reaches the first threshold voltage, the kickback voltage detection module issues the detection signal to the driving module and the second NMOSFET is turned on so as to have a third residual current to flow through the second NMOSFET, the coil and the first NMOSFET.
[0015] In one embodiment of the present invention, the kickback voltage detection module further includes a third threshold voltage. While in the first switch stage and as the first kickback voltage reaches the third threshold voltage, the kickback voltage detection module further issues the detection signal to the driving module and the first PMOSFET is turned on so as to have the first residual current to further flow through the first PMOSFET, the coil and the second NMOSFET. Further, the first threshold voltage is less than 0, and the third threshold voltage is smaller than the first threshold voltage.
[0016] In one embodiment of the present invention, the kickback voltage detection module further includes a fourth threshold voltage. While in the second switch stage and as the second kickback voltage reaches the fourth threshold voltage, the kickback voltage detection module further issues the detection signal to the driving module and the second NMOSFET is turned on so as to have the second residual current to further flow through the first PMOSFET, the coil and the second NMOSFET. Further, the first PMOSFET and the second PMOSFET couples electrically with a source voltage, the second threshold voltage is larger than the source voltage, and the fourth threshold voltage is larger than the second threshold voltage.
[0017] In one embodiment of the present invention, while in the third switch stage and as the second kickback voltage reaches the third threshold voltage, the kickback voltage detection module further issues the detection signal to the driving module and the second PMOSFET is turned on so as to have the third residual current to further flow through the second PMOSFET, the coil and the first NMOSFET. Further, prior to the first switch stage, the driving module engages electrically the first PMOSFET and the second NMOSFET so as to have a current to flow through the first PMOSFET, the coil and the second NMOSFET, such that the driving module introduces a first current phase to drive the motor.
[0018] In one embodiment of the present invention, after the second switch stage and as the kickback voltage detection module senses that the first kickback voltage is zero, the driving module engages electrically the second PMOSFET and the first NMOSFET so as to have the current to flow through the second PMOSFET, the coil and the first NMOSFET, which is the second current phase to drive the motor.
[0019] By providing the driving switching system for motors in accordance with the present invention, the timing of the first kickback voltage reaching the first threshold voltage, which defines the first switch stage, would push the system to flow the current through the first NMOSFET; the timing of the second kickback voltage reaching the second threshold voltage, which defines the second switch stage, would push the system to flow the current through the second PMOSFET and, as the first kickback voltage reaches the first threshold voltage, further to flow the current through the first PMOSFET and the first NMOSFET is forced to turn off; and, the timing of the second kickback voltage reaching the first threshold voltage, which defines the third switch stage, would push the system to flow the current through the second NMOSFET. Accordingly, based on the determination of whether the kickback voltage reaches the first threshold voltage, current flow is switched to the preferred MOSFET, and thus the kickback voltage can be reduced so as to protect the MOSFETs and ensure the driving efficiency upon the motor.
[0020] Further, in the preset invention, as the kickback voltage reaches the second threshold voltage, one more MOSFET is selected to share the load and thus to reduce the kickback voltage immediately. Upon such an arrangement, the safety and efficiency in driving the motor can be definitely enhanced.
[0021] All these objects are achieved by the driving switching system applied to motors described below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The present invention will now be specified with reference to its preferred embodiment illustrated in the drawings, in which:
[0023] FIG. 1 is a schematic view of the preferred driving switching system applied to motors in accordance with the present invention;
[0024] FIG. 2 through FIG. 2B illustrate schematically the switching of FIG. 1 in the first switching stage;
[0025] FIG. 3 through FIG. 3A illustrate schematically the switching of FIG. 1 in the second switching stage; and
[0026] FIG. 4 through FIG. 4B illustrate schematically the switching of FIG. 1 in the third switching stage.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] The invention disclosed herein is directed to a driving switching system applied to motors. In the following description, numerous details are set forth in order to provide a thorough understanding of the present invention. It will be appreciated by one skilled in the art that variations of these specific details are possible while still achieving the results of the present invention. In other instance, well-known components are not described in detail in order not to unnecessarily obscure the present invention.
[0028] Referring now to FIG. 1 , a preferred embodiment of the driving switching system for motors in accordance with the present invention is schematically shown. As shown, the system 1 for driving the motor (not shown in the figure) includes an H-bridge circuit 11 , two kickback voltage detection modules 12 , 12 a and two driving modules 13 , 13 a.
[0029] The H-bridge circuit 11 includes a first PMOSFET 111 , a first NMOSFET 112 , a second PMOSFET 113 and a second NMOSFET 114 .
[0030] The first PMOSFET 111 has a first source end (not labeled in the figure), a first drain end (not labeled in the figure) and a first gate end (not labeled in the figure). The first source end of the first PMOSFET 111 is electrically connected to a power source 2 with a VDD voltage.
[0031] The first NMOSFET 112 has a second source end (not labeled in the figure), a second drain end (not labeled in the figure) and a second gate end (not labeled in the figure). The second source end is grounded to have a ground voltage VSS, and the second drain end is electrically connected to the first drain end so as to form a first connection terminal A.
[0032] The second PMOSFET 113 has a third source end (not labeled in the figure), a third drain end (not labeled in the figure) and a third gate end (not labeled in the figure). The third source end of the second PMOSFET 113 is electrically connected to the power source 2 .
[0033] The second NMOSFET 114 has a fourth source end (not labeled in the figure), a fourth drain end (not labeled in the figure) and a fourth gate end (not labeled in the figure). The fourth source end is grounded, and the fourth drain end is electrically connected to the third drain end so as to form a second connection terminal B. The first connection terminal A and the second connection terminal B are electrically connected with a coil 3 .
[0034] In the present invention, the kickback voltage detection modules 12 , 12 a are both preset with a first threshold voltage, a second threshold voltage, a third threshold voltage and a fourth threshold voltage. The first threshold voltage is less than zero. (In the present invention, for the second source end and the fourth source end are both grounded to VSS, so the preset value for the first threshold voltage is less than zero, which is the potential of VSS) The third threshold voltage is smaller than the first threshold voltage, while the second threshold voltage is larger than the VDD of the power source 2 . The fourth threshold voltage is greater than the second threshold voltage, and thus greater than the VDD. In addition, the kickback voltage detection module 12 is electrically connected to the first connection terminal A, while another kickback voltage detection module 12 a is electrically connected to the second connection terminal B.
[0035] The kickback voltage detection module 12 is to detect a first kickback voltage at the first connection terminal A so as to evaluate whether or not the first kickback voltage reaches the first threshold voltage, the second threshold voltage, the third threshold voltage or the fourth threshold voltage. As a positive detection is met, a corresponding detection signal S 1 is issued. On the other hand, the kickback voltage detection module 12 a is to detect a second kickback voltage at the second connection terminal B so as to evaluate whether or not the second kickback voltage reaches the first threshold voltage, the second threshold voltage, the third threshold voltage or the fourth threshold voltage. As a positive detection is met, a corresponding detection signal S 1 a is issued.
[0036] The driving module 13 coupled electrically with the kickback voltage detection module 12 is to receive the detection signal S 1 from the kickback voltage detection module 12 . During a first switch stage, a second switch stage and a third switch stage, the motor is driven by switched around on the first PMOSFET 111 and the first NMOSFET 112 .
[0037] The driving module 13 a coupled electrically with the kickback voltage detection module 12 a is to receive the detection signal S 1 a from the kickback voltage detection module 12 a. During a first switch stage, a second switch stage and a third switch stage, the motor is driven by switched around on the second PMOSFET 113 and the second NMOSFET 114 .
[0038] In practice, in the preferred embodiment of the present invention, the process to drive the motor is actually separated into the first switch stage, the second switch stage and the third switch stage. In view of the direction change of the coil current, only two switch stages are included. The driving modules 13 , 13 a in any of the first switch stage, the second switch stage and the third switch stage are to receive the detection signals S 1 and S 1 a and evaluate if any of the first kickback voltage threshold, the second kickback voltage threshold, the third kickback voltage threshold and the fourth kickback voltage threshold is reached. Upon the evaluation results, the driving modules 13 , 13 a proceed to perform switching of current flow through around the first PMOSFET 111 , the first NMOSFET 112 , the second PMOSFET 113 and the second NMOSFET 114 .
[0039] Besides FIG. 1 , please also refer to FIG. 2 through FIG. 2B , FIG. 3 through FIG. 3A and FIG. 4 through FIG. 4B , in which the switching of FIG. 1 in the first, second and third switch stages are illustrated schematically, respectively.
[0040] As shown, prior to the first switch stage, the driving modules 13 , 13 a engages electrically respectively the first PMOSFET 111 and the second NMOSFET 114 , such that the first current flow I 1 can flow from the first PMOSFET 111 , the coil 3 and the second NMOSFET 114 . Thereby, the driving modules 13 , 13 a can introduce a first current phase to drive the motor. As shown in FIG. 2 , at this time, a pulse width modulation (PWM) signal is “on” and applied to the first PMOSFET 111 , the voltage at the first connection terminal A is VDD−ΔVa, and the voltage at the second connection terminal B is VSS+ΔVb, in which the aforesaid and the below ΔVa and ΔVb are different values and depend upon the current flowing through the corresponding MOSFETs.
[0041] While in the first switch stage, the driving module 13 turns off the first PMOSFET 111 and, as the first kickback voltage at the first connection terminal A reaches the first threshold voltage, the kickback voltage detection module 12 issues the detection signal S 1 to the driving module 13 and the first NMOSFET 112 is turned on so as to have a first residual current Ia of the coil 3 to flow through the first NMOSFET 112 , the coil 3 and the second NMOSFET 114 . As shown in FIG. 2A , at this time, the pulse width modulation (PWM) signal is “off”, the voltage at the first connection terminal A is VSS−ΔVa, and the voltage at the second connection terminal B is VSS+ΔVb.
[0042] Furthermore, while in the first switch stage and as the first kickback voltage reaches the third threshold voltage, the kickback voltage detection module 12 would issue again a detection signal S 1 to the driving module 13 and the first PMOSFET 111 is turned on so as to have the first residual current Ia (originally flowing through the first NMOSFET 112 , the coil 3 and the second NMOSFET 114 ) to further flow through the first PMOSFET 111 , the coil 3 and the second NMOSFET 114 . As shown in FIG. 2B , the first residual current Ia is consisted of the current Iap from the first PMOSFET 111 and the current Ian from the first NMOSFET 112 . In addition, the PWM signal is “off”, the voltage at the first connection terminal A is VSS−ΔVa, and the voltage at the second connection terminal B is VSS+ΔVb.
[0043] Prior to the second switch stage, the current flow is shown in either FIG. 2A or FIG. 2B . At this time, the PWM signal is “on” and applied to the second NMOSFET 114 , the voltage at the first connection terminal A is VSS−ΔVa, and the voltage at the second connection terminal B is VSS+ΔVb. While in the second switch stage, the driving module 13 a turns off the second NMOSFET 114 and, as the second kickback voltage reaches the second threshold voltage, the kickback voltage detection module 12 a issues the detection signal S 1 a to the driving module 13 a and the second PMOSFET 113 is turned on. Further, for the first kickback voltage still exists at the first connection terminal A, as the first kickback voltage reaches the first threshold voltage, the kickback voltage detection module 12 issues the detection signal s 1 to the driving module 13 and the first PMOSFET 111 is turned on and, on the other hand, the first NMOSFET 112 is forced to be turned off so as to have a second residual current Ib to flow through the first PMOSFET 111 , the coil 3 and the second PMOSFET 113 . At this time as shown in FIG. 3 , the second PMOSFET 113 is turned on, the voltage at the first connection terminal A is VSS−ΔVa, and the voltage at the second connection terminal B is VSS+ΔVb.
[0044] While in the second switch stage and as the second kickback voltage reaches the fourth threshold voltage, the kickback voltage detection module 12 a would issue the detection signal S 1 a to the driving module 13 a and the second NMOSFET 114 is turned on so as to have the second residual current Ib (originally flowing through the first PMOSFET 111 , the coil 3 and the second PMOSFET 113 ) to further flow through the first PMOSFET 111 , the coil 3 and the second NMOSFET 114 . As shown in FIG. 3A , the second residual current Ib is bifurcated to the current Ibp through the second PMOSFET 113 and the current Ibn through the second NMOSFET 114 . In addition, the PWM signal is “off”, the voltage at the first connection terminal A is VSS−ΔVa, and the voltage at the second connection terminal B is VSS+ΔVb.
[0045] After the second switch stage, as the kickback voltage detection module 12 detects that the first kickback voltage at the first connection terminal A is zero, which also means the current of the coil 3 is zero, the driving modules 13 , 13 a are to turn on the first NMOSFET 112 and the second PMOSFET 113 , respectively, so as to have the current I 2 to flow through the second PMOSFET 113 , the coil 3 and the first NMOSFET 112 . At this time as shown in FIG. 4 , the PWM signal is “on”, the voltage at the first connection terminal A is VSS+ΔVa, and the voltage at the second connection terminal B is VDD−ΔVb. Then, the driving module 13 , 13 a introduce the second current phase to drive the motor, and, after the driving module 13 a turns off the second PMOSFET 113 , the operation is to enter the third switch stage.
[0046] While in the third switch stage, the driving module 13 a turns off the second PMOSFET 113 and, as the second kickback voltage reaches the first threshold voltage, the kickback voltage detection module 12 a issues the detection signal S 1 a to the driving module 13 a and the second NMOSFET 114 is turned on so as to have a third residual current Ic of the coil 3 to flow through the second NMOSFET 114 , the coil 3 and the first NMOSFET 112 . As shown in FIG. 4A , the PWM signal is “off”, the voltage at the first connection terminal A is VSS+ΔVa, and the voltage at the second connection terminal B is VSS−ΔVb.
[0047] Further, while in the third switch stage and as the second kickback voltage reaches the third threshold voltage, the kickback voltage detection module 12 a issues the detection signal S 1 a to the driving module 13 a and the second PMOSFET 113 is turned on so as to have the third residual current Ic (originally flowing through the second NMOSFET 114 , the coil 3 and the first NMOSFET 112 ) to further flow through the second PMOSFET 113 , the coil 3 and the first NMOSFET 112 . As shown in FIG. 4B , the third residual current Ic is consisted of the current Icp from the second PMOSFET 113 and the current Icn from the second NMOSFET 112 . In addition, as the PWM signal is “off”, the voltage at the first connection terminal A is VSS+ΔVa, and the voltage at the second connection terminal B is VSS−ΔVb.
[0048] In summary, by introducing the driving switching system applied to motors in accordance with the present invention, due to various MOSFET switching are determined by being based on if the kickback voltage reaches the first preset threshold voltage, the kickback voltage can be reduced to a degree to protect the MOSFETs and enhance the motor's driving efficiency. Further, in the present invention, if the second threshold voltage is reached by the kickback voltage, an additional MOSFET is chosen to flow the current so as to rapidly reduce the kickback voltage and thus to further ensure the safety of motor driving and the driving efficiency.
[0049] While the present invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be without departing from the spirit and scope of the present invention. | A driving switching system includes an H-bridge circuit, at least a kickback voltage detection module and at least a driving module. The H-bridge circuit includes a first P-type MOSFET, a first N-type MOSFET, a second P-type MOSFET and a second N-type MOSFET. The first N-type MOSFET connects the first P-type MOSFET to have a first connection terminal, and the second N-type MOSFET connects the second P-type MOSFET to have a second connection terminal, in which both the terminals are connected to a coil. The kickback voltage detection module is used to detect a first kickback voltage at the first connection terminal and a second kickback voltage at the second connection terminal. The driving module switches the P-type MOSFET and the N-type MOSFET so as to drive a motor as the first or the second kickback voltage reaches a first or a second threshold. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a U.S. divisional application filed under 37 USC 1.53(b) claiming priority benefit of U.S. Ser. No. 11/812,656 filed in the United States on Jun. 20, 2007, which claims earlier priority benefit to Korean Patent Application No. 10-2007-0017343 filed with the Korean Intellectual Property Office on Feb. 21, 2007, the disclosures of which are incorporated herein by reference.
BACKGROUND
[0002] 1. Field
[0003] The present invention relates to a hydrogen generating apparatus, more particularly to a hydrogen generating apparatus that can control the amount of generation of hydrogen supplied to a fuel cell.
[0004] 2. Description of the Related Art
[0005] A fuel cell refers to an energy conversion apparatus that directly converts chemical energy of a fuel (hydrogen, LNG, LPG, methanol, etc.) and air to electricity and/or heat by means of an electrochemical reaction. Unlike a conventional power generation technology that requires fuel combustion, steam generation, or a turbine or power generator, the fuel cell technology needs no combustion process or driving device, thereby boosting energy efficiency and curbing environmental problems.
[0006] FIG. 1 illustrates an operational architecture of a fuel cell.
[0007] Referring to FIG. 1 , a fuel cell 100 is composed of an anode as a fuel pole 110 and a cathode as an air pole 130 . The fuel pole 110 is provided with hydrogen molecules (H 2 ), and decomposes them into hydrogen ions (H + ) and electrons (e). The hydrogen ion (H + ) moves toward the air pole 130 via a membrane 120 , which is an electrolyte layer. The electron moves through an external circuit 140 to generate an electric current. In the air pole 130 , the hydrogen ions and the electrons are combined with oxygen molecules in the atmosphere, generating water molecules. The following chemical formulas represent the above chemical reactions occurring in the fuel cell 100 .
[0000] Fuel pole 110: H 2 →2H + +2e −
[0000] Air pole 130: ½O 2 +2H + +2e − →H 2 0
[0000] Overall reaction: H 2 +½O 2 →H 2 0 CHEMICAL FORMULA 1
[0008] In short, the fuel cell 100 functions as a battery by supplying the electric current, generated due to the flowing of the decomposed electrons, to the external circuit 140 . Such a fuel cell 100 hardly emits an atmospheric pollutant such as Sox and NOx and makes little noise and vibration.
[0009] Meanwhile, in order to produce electrons in the fuel pole 110 , the fuel cell 100 necessitates a hydrogen generating apparatus that can change a common fuel to hydrogen gas.
[0010] A hydrogen storage tank, generally known as a hydrogen generating apparatus, however, occupies a large space and should be kept with care.
[0011] Moreover, as a portable electronic device, such as a mobile phone and a notebook computer, requires a large capacity of power, it is necessary that the fuel cell have a large capacity and perform high performance while it is small.
[0012] In order to meet the above needs, methanol or formic acid, permitted to be brought into an airplane by International Civil Aviation Organization (ICAO), is used for fuel reforming, or methanol, ethanol, or formic acid is directly used as a fuel for the fuel cell.
[0013] However, the former case requires a high reforming temperature, has a complicated system, consumes driving power, and contains impurities (e.g., CO 2 and CO) in addition to pure hydrogen. The latter case deteriorates power density due to a low rate of a chemical reaction in the anode and a cross-over of hydrocarbon through the membrane.
SUMMARY
[0014] The present invention provides a hydrogen generating apparatus, a fuel cell power generation system, a method of controlling the quantity of hydrogen generation, and a recorded medium recorded with a program performing the method that can generate pure hydrogen at room temperature through an electrochemical reaction.
[0015] The present invention also provides a hydrogen generating apparatus, a fuel cell power generation system, a method of controlling the quantity of hydrogen generation, and a recorded medium recorded with a program performing the method that can control the quantity of hydrogen generation without a separate BOP (Balance of Plant) unit while maintaining a simple structure.
[0016] The present invention also provides a hydrogen generating apparatus, a fuel cell power generation system, a method of controlling the quantity of hydrogen generation, and a recorded medium recorded with a program performing the method that are economical and eco-friendly.
[0017] The present invention also provides a hydrogen generating apparatus, a fuel cell power generation system, a method of controlling the quantity of hydrogen generation, and a recorded medium recorded with a program performing the method that can control the quantity of hydrogen generation by use of On/Off time and/or On/Off frequency of a switch.
[0018] Moreover, the present invention provides a hydrogen generating apparatus, a fuel cell power generation system, a method of controlling the quantity of hydrogen generation, and a recorded medium recorded with a program performing the method that can prevent waste or risk of leaking surplus hydrogen in the air simply by turning on the switch and reduce the noise and power consumption by not using a gas pump or a liquid pump.
[0019] An aspect of the present invention features a hydrogen generating apparatus that is capable of controlling the amount of hydrogen generation.
[0020] The hydrogen generating apparatus in accordance with an embodiment of the present invention includes an electrolyzer, which is filled with an aqueous electrolyte solution containing hydrogen ions, a first electrode, which is accommodated in the electrolyzer, is submerged in the aqueous electrolyte solution, and generates electrons, a second electrode, which is accommodated in the electrolyzer, is submerged in the aqueous electrolyte solution, and receives the electrons to generate hydrogen, a switch, which is located between the first electrode and the second electrode, a flow rate meter, which measures an amount of hydrogen generation in the second electrode, and a switch controller, which receives a set value, compares the amount of hydrogen generation measured by the flow rate meter with the set value, and controls an on/off status of the switch.
[0021] The switch controller can be inputted with the set value directly from a user through an input unit. The hydrogen generating apparatus can be coupled to a fuel cell and supplies hydrogen, and the switch controller can be inputted with the set value in accordance with an amount of hydrogen generation that is required by the fuel cell.
[0022] The metal forming the first electrode can have a higher ionization tendency than a metal forming the second electrode.
[0023] The flow rate meter can measure the amount of hydrogen generation in units of flowrate. The switch controller can generate and output a switch control signal turning the switch on and off, and the switch controller can determine an on/off ratio of the switch within one cycle by varying a duty ratio of the switch control signal.
[0024] The switch controller can control a fluctuation in the amount of hydrogen generation by varying an on/off frequency of the switch control signal. The switch controller can compare the set value with the measured amount of hydrogen generation, and can increase the duty ratio if the amount of hydrogen generation is smaller than the set value, reduce the duty ratio if the amount of hydrogen generation is greater than the set value, and maintain the duty ratio if the amount of hydrogen generation is equal to the set value. The set value includes an upper limit and a lower limit, and the switch controller can compare the set value with the measured amount of hydrogen generation, and can increase the duty ratio if the amount of hydrogen generation is smaller than the lower limit, reduce the duty ratio if the amount of hydrogen generation is greater than the upper limit, and maintain the duty ratio if the amount of hydrogen generation is between the lower limit and the upper limit.
[0025] Another aspect of the present invention features a fuel cell power generation system including a hydrogen generating apparatus that is capable of controlling the amount of hydrogen generation.
[0026] The fuel cell power generation system in accordance with an embodiment of the present invention has a hydrogen generating apparatus, which controls an amount of hydrogen generation by controlling an on/off status of a switch connected between electrodes, and a fuel cell, which is supplied with hydrogen generated by the hydrogen generating apparatus and produces a direct current by converting chemical energy of the hydrogen to electrical energy.
[0027] The hydrogen generating apparatus can include an electrolyzer, which is filled with an aqueous electrolyte solution containing hydrogen ions, a first electrode, which is accommodated in the electrolyzer, is submerged in the aqueous electrolyte solution, and generates electrons, a second electrode, which is accommodated in the electrolyzer, is submerged in the aqueous electrolyte solution, and receives the electrons to generate hydrogen, a switch, which is located between the first electrode and the second electrode, a meter, which measures an amount of hydrogen generation or an output of a fuel cell, and a switch controller, which receives a set value, compares the amount of hydrogen generation or the output of the fuel cell measured by the meter with the set value, and controls an on/off status of the switch.
[0028] The switch controller can be inputted with the set value directly from a user through an input unit. The hydrogen generating apparatus can be coupled to the fuel cell and supply hydrogen, and the switch controller can be inputted with the set value in accordance with an amount of electric power, voltage, current, impedance or a combination thereof or an amount of hydrogen generation that is required by the fuel cell.
[0029] The metal forming the first electrode can have a higher ionization tendency than a metal forming the second electrode.
[0030] The switch controller can generate and output a switch control signal turning the switch on and off, and the switch controller can determine an on/off ratio of the switch within one cycle by varying a duty ratio of the switch control signal. The meter can be a flow rate meter that measures the amount of hydrogen generated in the second electrode in units of flowrate. The switch controller can control a fluctuation in the amount of hydrogen generation by varying an on/off frequency of the switch control signal. The switch controller can compare the set value with the measured amount of hydrogen generation, and can increase the duty ratio if the amount of hydrogen generation is smaller than the set value, reduce the duty ratio if the amount of hydrogen generation is greater than the set value, and maintain the duty ratio if the amount of hydrogen generation is equal to the set value. The set value can include an upper limit and a lower limit, and the switch controller can compare the set value with the measured amount of hydrogen generation, and can increase the duty ratio if the amount of hydrogen generation is smaller than the lower limit, reduce the duty ratio if the amount of hydrogen generation is greater than the upper limit, and maintain the duty ratio if the amount of hydrogen generation is between the lower limit and the upper limit.
[0031] The meter can be an output meter that measures an output of the fuel cell in units of watt (W), volt (V), ampere (A), ohm (Ω) or a combination thereof. The switch controller can control a fluctuation in the output of the fuel cell by varying an on/off frequency of the switch control signal. The switch controller can compare the set value with the measured output of the fuel cell, and can increase the duty ratio if the output of the fuel cell is smaller than the set value, reduce the duty ratio if the output of the fuel cell is greater than the set value, and maintain the duty ratio if the output of the fuel cell is equal to the set value. The set value can include an upper limit and a lower limit, and the switch controller can compare the set value with the measured output of the fuel cell, and can increase the duty ratio if the output of the fuel cell is smaller than the lower limit, reduce the duty ratio if the output of the fuel cell is greater than the upper limit, and maintain the duty ratio if the output of the fuel cell is between the lower limit and the upper limit.
[0032] Another aspect of the present invention features a method of controlling an amount of hydrogen generation in a hydrogen generating apparatus controlling an amount of hydrogen generation by controlling an on/off status of a switch located between electrodes.
[0033] The method of controlling an amount of hydrogen generation in accordance with an embodiment of the present invention includes the steps of being inputted with a set value; comparing a measured amount of hydrogen generation and the set value; and increasing a duty ratio of a switch control signal if the amount of hydrogen generation is smaller than the set value, reducing the duty ratio of the switch control signal if the amount of hydrogen generation is greater than the set value, and maintaining the duty ratio of the switch control signal if the amount of hydrogen generation is equal to the set value, in which the switch control signal controls the on/off status of the switch within one cycle in accordance with the duty ratio.
[0034] The method of controlling an amount of hydrogen generation in accordance with another embodiment of the present invention includes the steps of being inputted with an upper value and a lower value; comparing a measured amount of hydrogen generation with the upper value and the lower value; and increasing a duty ratio of a switch control signal if the amount of hydrogen generation is smaller than the lower value, reducing the duty ratio of the switch control signal if the amount of hydrogen generation is greater than the upper value, and maintaining the duty ratio of the switch control signal if the amount of hydrogen generation is between the lower value and the upper value, in which the switch control signal controls the on/off status of the switch within one cycle in accordance with the duty ratio.
[0035] The method of controlling an amount of hydrogen generation in accordance with yet another embodiment of the present invention includes the steps of being inputted with a set value; comparing an output of the fuel cell and the set value; and increasing a duty ratio of a switch control signal if the output of the fuel cell is smaller than the set value, reducing the duty ratio of the switch control signal if the output of the fuel cell is greater than the set value, and maintaining the duty ratio of the switch control signal if the output of the fuel cell is equal to the set value, in which the switch control signal controls the on/off status of the switch within one cycle in accordance with the duty ratio.
[0036] The method of controlling an amount of hydrogen generation in accordance with yet another embodiment of the present invention includes the steps of being inputted with an upper value and a lower value; comparing a measured output of the fuel cell with the upper value and the lower value; and increasing a duty ratio of a switch control signal if the output of the fuel cell is smaller than the lower value, reducing the duty ratio of the switch control signal if the output of the fuel cell is greater than the upper value, and maintaining the duty ratio of the switch control signal if the output of the fuel cell is between the lower value and the upper value, in which the switch control signal controls the on/off status of the switch within one cycle in accordance with the duty ratio.
[0037] Another aspect of the present invention features a recording medium having recorded a computer readable program to control an amount of hydrogen generation in a hydrogen generating apparatus controlling an amount of hydrogen generation by controlling an on/off status of a switch located between electrodes. A program performing a method of controlling an amount of hydrogen generation described above is recorded in the recording medium, which is readable by a computer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] These and other features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims and accompanying drawings where:
[0039] FIG. 1 illustrates an operational architecture of a fuel cell;
[0040] FIG. 2 shows a sectional view of a hydrogen generating apparatus in accordance with an embodiment of the present invention;
[0041] FIG. 3 is a graph showing how the amount of electric current between a first electrode and a second electrode and the amount of generated hydrogen are related in a hydrogen generating apparatus in accordance with an embodiment of the present invention;
[0042] FIG. 4 shows a block diagram of a control unit of a hydrogen generating apparatus in accordance with an embodiment of the present invention;
[0043] FIG. 5 shows a block diagram of a control unit of a hydrogen generating apparatus in accordance with another embodiment of the present invention;
[0044] FIG. 6 is a graph indicating quantities of generated hydrogen, expressed in flow rate, when the switch is turned on;
[0045] FIG. 7A shows a first example of On/Off frequencies of the switch of a hydrogen generating apparatus in accordance with an embodiment of the present invention;
[0046] FIG. 7B shows a second example of On/Off frequencies of the switch of a hydrogen generating apparatus in accordance with an embodiment of the present invention;
[0047] FIG. 8 shows the relation between time and quantity of hydrogen generation when the On/Off frequency of the switch is controlled;
[0048] FIG. 9A shows a first example of duty ratios of the switch of a hydrogen generating apparatus in accordance with an embodiment of the present invention;
[0049] FIG. 9B shows a second example of duty ratios of the switch of a hydrogen generating apparatus in accordance with an embodiment of the present invention;
[0050] FIG. 10 shows the relation between time and quantity of hydrogen generation when the duty ratio of the switch is controlled;
[0051] FIG. 11 shows a flowchart of a method of controlling the quantity of hydrogen generation in a hydrogen generating apparatus in accordance with an embodiment of the present invention; and
[0052] FIG. 12 shows a flowchart of a method of controlling the quantity of hydrogen generation in a hydrogen generating apparatus in accordance with another embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0053] Since there can be a variety of permutations and embodiments of the present invention, certain embodiments will be illustrated and described with reference to the accompanying drawings. This, however, is by no means to restrict the present invention to certain embodiments, and shall be construed as including all permutations, equivalents and substitutes covered by the spirit and scope of the present invention. Throughout the drawings, similar elements are given similar reference numerals. Throughout the description of the present invention, when describing a certain technology is determined to evade the point of the present invention, the pertinent detailed description will be omitted.
[0054] Terms such as “first” and “second” can be used in describing various elements, but the above elements shall not be restricted to the above terms. The above terms are used only to distinguish one element from the other. For instance, the first element can be named the second element, and vice versa, without departing the scope of claims of the present invention. The term “and/or” shall include the combination of a plurality of listed items or any of the plurality of listed items.
[0055] When one element is described as being “connected” or “accessed” to another element, it shall be construed as being connected or accessed to the other element directly but also as possibly having another element in between. On the other hand, if one element is described as being “directly connected” or “directly accessed” to another element, it shall be construed that there is no other element in between.
[0056] The terms used in the description are intended to describe certain embodiments only, and shall by no means restrict the present invention. Unless clearly used otherwise, expressions in the singular number include a plural meaning. In the present description, an expression such as “comprising” or “consisting of” is intended to designate a characteristic, a number, a step, an operation, an element, a part or combinations thereof, and shall not be construed to preclude any presence or possibility of one or more other characteristics, numbers, steps, operations, elements, parts or combinations thereof.
[0057] Unless otherwise defined, all terms, including technical terms and scientific terms, used herein have the same meaning as how they are generally understood by those of ordinary skill in the art to which the invention pertains. Any term that is defined in a general dictionary shall be construed to have the same meaning in the context of the relevant art, and, unless otherwise defined explicitly, shall not be interpreted to have an idealistic or excessively formalistic meaning.
[0058] Hereinafter, certain embodiments will be described in detail with reference to the accompanying drawings. Identical or corresponding elements will be given the same reference numerals, regardless of the figure number, and any redundant description of the identical or corresponding elements will not be repeated.
[0059] FIG. 2 is a sectional view of a hydrogen generating apparatus in accordance with an embodiment of the present invention.
[0060] A hydrogen generating apparatus 200 includes an electrolyzer 210 , a first electrode 220 , a second electrode 230 and a control unit 240 . For the convenience of description and understanding, it will be presumed below that the first electrode 220 is composed of magnesium (Mg) and the second electrode 230 is composed of stainless steel.
[0061] The electrolyzer 210 is filled with an aqueous electrolyte solution 215 . The aqueous electrolyte solution 215 contains hydrogen ions, which are used by the hydrogen generating apparatus 200 to generate hydrogen gas.
[0062] Examples of the electrolyte for the aqueous electrolyte solution 215 are LiCl, KCl, NaCl, KNO 3 , NaNO 3 , CaCl 2 , MgCl 2 , K 2 SO 4 , Na 2 SO 4 , MgSO 4 , AgCl, or the like.
[0063] The electrolyzer 210 accommodates the first electrode 220 and the second electrode 230 , the entirety or portions of which are submerged in the electrolyte solution 215 .
[0064] The first electrode 220 is an active electrode, where the magnesium (Mg) is oxidized to magnesium ions (Mg 2+ ), releasing electrons due to the difference in ionization energies of magnesium and water. The released electrons move to the second electrode 230 through a first electric wire 225 , the control unit 240 and a second electric wire 235 .
[0065] The second electrode 230 is an inactive electrode, where the water molecules receive the electrons moved from the first electrode 220 and then are decomposed into the hydrogen molecules.
[0066] The above chemical reactions can be represented as the following chemical formula 2:
[0000] First electrode 220: Mg→Mg 2+ +2 e−
[0000] Second electrode 230: 2H 2 0+2 e− →H 2 +2(OH) −
[0000] Overall reaction: Mg+2H 2 O→Mg(OH) 2 +H 2 CHEMICAL FORMULA 2
[0067] The reaction rate and the efficiency of the chemical reaction depend on various factors, including the area of the first electrode 220 and/or the second electrode 230 , the concentration of the aqueous electrolyte solution 215 , the type of the aqueous electrolyte solution 215 , the number of the first electrode 220 and/or the second electrode 230 , the method of connecting the first electrode 220 and the second electrode 230 , the electric resistance between the first electrode 220 and the second electrode 230 .
[0068] Changing any of the above factors affects the amount of electric current (that is, the amount of electrons) flowing between the first electrode 220 and the second electrode 230 , thereby altering the reaction rate of the electrochemical reaction shown in CHEMICAL FORMULA 2, which in turn changes the amount of hydrogen generated in the second electrode 230 .
[0069] Therefore, the amount of the hydrogen generated in the second electrode 230 can be controlled by controlling the amount of the electric current that flows between the first electrode 220 and the second electrode 230 . Faraday's law explains this as shown in MATHEMATICAL FORMULA 1 below.
[0000]
MATHEMATICAL
FORMULA
1
N
hydrogen
=
i
nE
N
hydrogen
=
i
2
×
96485
(
mol
)
V
hydrogen
=
i
2
×
96485
×
60
×
22400
(
ml
/
min
)
=
7
×
i
(
ml
/
min
)
[0070] where N hydrogen is the amount of hydrogen generated per second (mol/s), V hydrogen is the volume of hydrogen generated per minute (ml/min), i is the electric current (C/s), n is the number of the reacting electrons, and E is the electron charge per mole (C/mol).
[0071] In the case of the above CHEMICAL FORMULA 2, n has a value of 2 since two electrons react at the second electrode 230 , and E has a value of −96,485 C/mol.
[0072] The volume of hydrogen generated per minute can be calculated by multiplying the time (60 seconds) and the molar volume of hydrogen (22400 ml) to the amount of hydrogen generated per second.
[0073] For example, in the case that the fuel cell is used in a 2 W system, and it is assumed that the fuel cell is running a voltage of 0.6V at room temperature and that a hydrogen usage ratio is 60%, it takes 42 ml/mol of hydrogen and 6 A of electric current. In the case that the fuel cell is used in a 5 W system, it takes 105 ml/mol of hydrogen and 15 A of electric current.
[0074] The hydrogen generating apparatus 200 can meet the variable hydrogen demand of the fuel cell connected thereto by controlling the amount of electric current flowing through the first electric wire 225 , connected to the first electrode 220 , and the second electric wire 235 , connected to the second electrode 230 .
[0075] However, most of the factors that determine the rate of the hydrogen generation reaction occurring in the second electrode of the hydrogen generating apparatus 200 , except the electric resistance between the first electrode 220 and the second electrode 230 , are hardly changeable once the hydrogen generating apparatus 200 is manufactured.
[0076] Therefore, the hydrogen generating apparatus 200 according to this embodiment of the present invention has the control unit 240 disposed between the first electric wire 225 and the second electric wire 235 , which connect the first electrode 220 and the second electrode 230 , in order to regulate the electric resistance between the first electrode 220 and the second electrode 230 .
[0077] Thus, the hydrogen generating apparatus 200 controls the electric resistance between the first electrode 220 and the second electrode 230 , that is, the amount of the electric current flowing therebetween, thereby generating as much hydrogen as needed by the fuel cell.
[0078] The first electrode 220 can be also composed of a metal having a relatively high ionization tendency, such as iron (Fe), aluminum (Al), zinc (Zn), or the like. The second electrode 230 can be also composed of a metal having a relatively low ionization tendency compared to the metal of the first electrode 220 , such as platinum (Pt), aluminum (Al), copper (Cu), gold (Au), silver (Ag), iron (Fe), or the like.
[0079] The control unit 240 controls a transfer rate, that is, the amount of electric current, at which electrons generated in the first electrode 220 are transferred to the second electrode 230 .
[0080] The control unit 240 receives information on the amount of power or hydrogen demanded for the fuel cell and, according to the information, controls the amount of electrons flowing from the first electrode 220 to the second electrode 230 . If the demanded amount of power or hydrogen is large, the control unit 240 increases the amount of electrons, and the control unit 240 reduces the amount of the electrons if the demanded amount of power or hydrogen is small.
[0081] The hydrogen generating apparatus 200 can receive the information on the amount of the power or the hydrogen demanded for the fuel cell from the fuel cell combined with the hydrogen generating apparatus 200 or from a user, who inputs the information through a separate input unit.
[0082] The hydrogen generating apparatus of the present invention can have a plurality of the first electrodes 220 and/or the second electrodes 230 . In the case that a plural number of the first electrode 220 and/or the second electrode 230 are disposed, it can take a shorter time to generate the demanded amount of hydrogen since the hydrogen generating apparatus 200 can generate more hydrogen per unit time.
[0083] FIG. 3 is a graph showing how the amount of electric current flowing between the first electrode 220 and the second electrode 230 is related to the volume of hydrogen generated on the second electrode 230 . Here, it should be noted that the volume of hydrogen is shown in flow-rate measured per minute, because not the total volume of generated hydrogen but the flow-rate of hydrogen is significant to a fuel cell.
An Experiment for FIG. 3 was Conducted Under the Following Conditions:
[0000]
First electrode 220 : Magnesium (Mg)
Second electrode 230 : Stainless steel
Distance between the electrodes: 3 mm
Ingredients and concentration of electrolyte: 30 wt % KCl
Number of the electrodes: Magnesium 3 each, Stainless steel 3 each
Electrode connecting method: Serial
Volume of aqueous electrolyte solution: 60 cc (excessive condition)
Size of the electrode: 24 mm×85 mm×1 mm
[0092] The above conditions were used for every graph referred to in describing the present invention.
[0093] FIG. 3 shows a greater flow rate of the hydrogen than a theoretical value based on MATHEMATICAL FORMULA 1, due to an interaction of the three pairs of electrodes.
[0094] Nevertheless, it is verified from FIG. 3 that the flow-rate of hydrogen is correlated with the amount of electric current between the first electrode 220 and the second electrode 230 . Also, the graph shows an almost linear relation between the flow-rate and the amount of the electric current, which agrees with the MATHEMATICAL FORMULA 1.
[0095] FIG. 4 is a block diagram of the control unit 240 of the hydrogen generating apparatus in accordance with an embodiment of the present invention.
[0096] The control unit 240 comprises a flow rate meter 410 , a switch controller 420 and a switch 430 .
[0097] The flow rate meter 410 measures the amount of hydrogen, in units of flow rate, generated from the second electrode 230 of the hydrogen generating apparatus. As described above, in order to use the hydrogen generating apparatus 200 in accordance with the present invention by coupling to a fuel cell, a certain amount of hydrogen generation, not a total quantity of hydrogen generation, should be maintained, and thus it is required that the amount of hydrogen generation be measured in units of ml/min. Of course, it is possible to use other measurement units as long as the unit is capable of measuring the flow rate.
[0098] The switch controller 420 is inputted with a set value, which is related to the amount of hydrogen generation. The hydrogen generating apparatus 200 is disposed with a separate input unit (not shown), through which the set value can be inputted by the user. The required amount of output (i.e. electric power, voltage, current, impedance, or a combination thereof) or hydrogen generation may be inputted by a fuel cell that is coupled to the hydrogen generating apparatus 200 . In the latter case, the fuel cell may be separately equipped with a hydrogen requiring unit for inputting the amount of output or hydrogen generation that is needed by the hydrogen generating apparatus 200 .
[0099] The switch controller 420 compares the inputted set value with the amount of hydrogen generation measured by the flow rate meter 410 . If the amount of generated hydrogen is smaller than the set value, the switch 430 is controlled to increase the amount of hydrogen generation, and if the amount of generated hydrogen is greater than the set value, the switch 430 is controlled to reduce the amount of hydrogen generation. It is assumed that the switch 430 is controlled by a switch control signal such that the switch controller 420 can turn the switch 430 on or off.
[0100] The switch is disposed between the first electrode 220 and the second electrode 230 . Electrons generated in the first electrode 220 is transferred to the second electrode 230 if the switch 430 is turned on, and the electrons generated in the first electrode 220 is not transferred to the second electrode 230 if the switch 430 is turned off.
[0101] That is, the control unit 240 controls the amount of hydrogen generation, using the switch 430 to control whether the electrons are to be transferred from the first electrode 220 to the second electrode 230 .
[0102] FIG. 5 is a block diagram of the control unit 240 of the hydrogen generating apparatus in accordance with another embodiment of the present invention.
[0103] The control unit 240 includes an output meter 510 , a switch controller 420 and a switch 430 . Here, the switch controller 420 and the switch 430 function the same way as described earlier with reference to FIG. 4 , and thus their description will be omitted.
[0104] The output meter 510 is connected to the fuel cell 100 to measure an output of the fuel cell 100 . Here, the output refers to, for example, the amount of electric power, voltage, current, impedance or a combination thereof of the fuel cell 100 that receives hydrogen, which is generated from the hydrogen generating apparatus 200 . The below description will focus on electric power as the output of the fuel cell.
[0105] As described above, a certain amount of hydrogen generation during certain duration, not a total amount of hydrogen generation, has to be maintained in order to use the hydrogen generating apparatus 200 in accordance with an embodiment of the present invention by coupling with the fuel cell. Therefore, the amount of electric power of the fuel cell 100 based on the amount of hydrogen generation is measured in units of watt (W). Of course, it is possible to use other units as long as the amount of electric power can be measured.
[0106] Although the below description focuses on the control with the switch 430 of a hydrogen generating apparatus that is equipped with the flow rate meter 410 shown in FIG. 4 , it shall be evident that the same description applies to a hydrogen generating apparatus 200 equipped with the output meter 510 shown in FIG. 5 .
[0107] FIG. 6 is a graph of the amount of hydrogen generation, expressed in units of flow rate, when the switch 430 is turned on.
[0108] If the switch 430 stays on for a while, the reaction becomes very fast at the beginning, raising the temperature and rapidly increasing the amount of hydrogen generation as much as 100 ml/min. Then, the amount of hydrogen generation quickly drops due to the reduction of water in the aqueous electrolyte solution and the metal composing the first electrode 220 .
[0109] In such a case, it becomes difficult to control the amount of hydrogen generation, and thus the amount of hydrogen generation is controlled to a desired flow rate by having the switch controller 420 control the turning on/off of the switch 430 such that the switch 430 has a certain duty ratio and/or on/off frequency. This will be further described with reference to FIG. 7A .
[0110] FIG. 7A is a first example of the on/off frequency of the switch of a hydrogen generating apparatus in accordance with an embodiment of the present invention, and FIG. 7B is a second example of the on/off frequency of the switch of a hydrogen generating apparatus in accordance with an embodiment of the present invention. Furthermore, FIG. 8 shows how the amount of hydrogen generation is related to time when the on/off frequency of the switch is controlled. It will be assumed hereinafter that the switch 430 is turned on when the size of an inputted switch control signal is M (i.e., high) and turned off when the size of an inputted switch control signal is 0 (i.e., low).
[0111] Referring to FIG. 7A , the switch control signal inputted to the switch 430 has a frequency of T and a duty ratio of 50%. In other words, the switch control signal inputted to the switch 430 is high for ½ T and low for ½ T.
[0112] Referring to FIG. 7B , on the other hand, the switch control signal inputted to the switch 430 has a frequency of ¼ T and a duty ratio of 50%. In other words, the switch control signal inputted to the switch 430 is high for ⅛ T and low for ⅛ T.
[0113] The switch control signal inputted to the switch 430 has a duty ratio (e.g., 50% in the case of FIGS. 7A and 7B ), and thus the switch 430 is turned on and off for the same duration within one cycle.
[0114] Referring to FIG. 8 , when the duty ratio of the switch 430 is controlled such that 42 ml/min of hydrogen is generated for a fuel cell that requires 2 W of electric power, there is fluctuation in the amount of hydrogen generation according to the on/off frequency. The temperature 810 of the hydrogen generating apparatus 200 increases steadily but stays below 80° C.
[0115] The amount of hydrogen generation 820 is close to 42 ml/min. When the on/off frequency is relatively small (i.e., a large cycle) as in FIG. 7A , the fluctuation is strong, as shown in boxes represented by 840 . When the on/off frequency is relatively large (i.e., a small cycle) as in FIG. 7B , the fluctuation is weak, as shown in boxes represented by 850 .
[0116] Therefore, for the same duty ratio, a relatively larger on/off frequency of the switch control signal causes less fluctuation and is easier to maintain the desired amount of hydrogen generation.
[0117] FIG. 9A is a first example of duty ratios of the switch of a hydrogen generating apparatus in accordance with an embodiment of the present invention, and FIG. 9B is a second example of duty ratios of the switch of a hydrogen generating apparatus in accordance with an embodiment of the present invention. FIG. 10 shows how the quantity of hydrogen generation is related to time when the duty ratio of the switch is controlled.
[0118] Referring to FIG. 9A , the switch control signal has a cycle of T and a duty ratio of 75%, that is, the switch control signal is high for ¾ T and low for ¼ T.
[0119] Referring to FIG. 9B , the switch control signal has a cycle of T, which is the same as that of FIG. 9A , and a duty ratio of 25%, that is, the switch control signal is high for ¼ T and low for ¾ T.
[0120] By controlling the duty ratio of the switch control signal that is inputted to the switch 430 , it becomes possible to control the amount of hydrogen generation per time that is generated in the hydrogen generating apparatus 200 .
[0121] Referring to FIG. 10 , the amount of hydrogen generation is left to increase naturally at the beginning (refer to the portion of graph represented by 1020 ), and then the switch controller 420 controls the on and off of the switch 430 to generate 42 ml/min ( 1021 ), 10 ml/min ( 1022 ), 42 ml/min ( 1023 ), 20 ml/min ( 1024 ) and 30 ml/min ( 1025 ) of hydrogen.
[0122] When the amount of hydrogen generation is adjusted from 42 ml/min ( 1021 ) to 10 ml/min ( 1022 ), the ratio of off-time of the switch control signal within one cycle is increased, that is, the duty ratio is gradually decreased. Then, by steadily maintaining the duty ratio when the flow rate meter 410 reads 10 ml/min of hydrogen generation, the amount of hydrogen generation is kept at 10 ml/min.
[0123] When the amount of hydrogen generation is adjusted from 10 ml/min ( 1022 ) to 42 ml/min ( 1023 ), the ratio of on-time of the switch control signal within one cycle is increased, that is, the duty ratio is gradually increased. Then, by steadily maintaining the duty ratio when the flow rate meter 410 reads 42 ml/min of hydrogen generation, the amount of hydrogen generation is kept at 42 ml/min.
[0124] By repeatedly performing the above adjustment of duty ratio, the switch controller 420 can adjust the amount of hydrogen generation according to changing set values.
[0125] As described with reference to FIGS. 7A to 8 , it is possible to control the fluctuation in the amount of hydrogen generation by changing the on/off frequency of the switch 430 in case a certain amount of hydrogen generation is maintained.
[0126] Moreover, the amount of hydrogen generation measured in units of flow rate in FIGS. 6 to 10 may be the amount of electric power outputted from the fuel cell 100 in a hydrogen generating apparatus 200 shown in FIG. 5 . For example, the flow rate of 42 ml/min shown in FIGS. 6 to 10 can correspond to 2 W, depending on the operation condition of the fuel cell 100 .
[0127] In other words, the earlier-measured amounts of hydrogen generation correspond to the output of the fuel cell (i.e., amount of electric power) that is measured by the output meter 510 of the hydrogen generating apparatus 200 . The amount of hydrogen generation to be controlled through the on/off control of the switch corresponds to the output of the fuel cell, that is, the amount of electric power.
[0128] The switch of the hydrogen generating apparatus in accordance with an embodiment of the present invention can be made of an MOS (metal-oxide semiconductor) transistor.
[0129] The switch controller of the hydrogen generating apparatus in accordance with an embodiment of the present invention can use a power circuit of the fuel cell and be included in a control unit of a fuel cell generating system. In other words, by including the switch controller in the control unit of a fuel cell generating system, the switch controller and the control unit of the fuel cell generating system can be made into one chip.
[0130] Moreover, the hydrogen generating apparatus of the present invention can compose a fuel cell generating system by being connected to a fuel cell. The fuel cell generating system includes a hydrogen generating apparatus that is possible to control the amount of hydrogen generation and a fuel cell that generates electricity by being supplied with hydrogen from the hydrogen generating apparatus.
[0131] FIG. 11 is a flowchart showing a method of controlling the amount of hydrogen generation in a hydrogen generating apparatus in accordance with an embodiment of the present invention. The hydrogen generating apparatus of FIG. 11 is illustrated in FIG. 4 .
[0132] The switch controller 420 of the hydrogen generating apparatus 200 turns on the switch 430 and generates hydrogen over a certain threshold of flow rate, in the step represented by S 1100 .
[0133] In step S 1110 , the flow rate meter 410 measures the amount of hydrogen generation, and in step S 1120 the switch controller 420 compares the amount of hydrogen generation, measured by the flow rate meter 410 , with an inputted set value. Here, the inputted set value can be one value, as shown in step S 1120 a, or have an upper limit and a lower limit with a range, as shown in step 1120 b.
[0134] The switch controller 420 generates a switch control signal for controlling the on/off of the switch according to the set value and applies the switch control signal to the switch 430 .
[0135] If one set value is inputted, as shown in step S 1120 a, the amount of hydrogen generation (A) and the set value (B) are compared in step S 1130 a. In case the amount of hydrogen generation is smaller than the set value (A<B), the duty ratio of the switch control signal is increased in step S 1132 a, and if the amount of hydrogen generation is greater than the set value (A>B), the duty ratio of the switch control signal is reduced in step S 1134 a. If the amount of hydrogen generation is equal to the set value (A=B), the current duty ratio of the switch control signal is maintained, in step S 1136 a.
[0136] In case the upper limit and the lower limit are inputted in step S 1120 b, the amount of hydrogen generation (A), the upper limit (B 1 ) and the lower limit (B 2 ) are compared in step 1130 b. If the amount of hydrogen generation is smaller than the lower limit (A<B 2 ), the duty ratio of the switch control signal is increased in step 1132 b, and if the amount of hydrogen generation is greater than the upper limit (A>B 1 ), the duty ratio of the switch control signal is reduced in step S 1134 b. If the amount of hydrogen generation is between the upper limit and the lower limit (B 2 =A=B 1 ), the current duty ratio of the switch control signal is maintained in S 1136 b.
[0137] By repeating steps S 1120 to S 1136 a or S 1136 b, the hydrogen generating apparatus 200 can generate the amount of hydrogen according to the inputted set value.
[0138] FIG. 12 is a flowchart showing a method of controlling the amount of hydrogen generation in a hydrogen generating apparatus in accordance with another embodiment of the present invention. The hydrogen generating apparatus of FIG. 12 is illustrated in FIG. 5 .
[0139] The switch controller 420 of the hydrogen generating apparatus 200 turns on the switch 430 and generates hydrogen over a certain threshold of flow rate, in the step represented by S 1200 .
[0140] The output meter 510 measures the output (e.g., amount of electric power) of the fuel cell, in the step represented by S 1210 , and the switch controller 420 compares the output of the fuel cell, measured by the output meter 510 , and the inputted set value in S 1220 . Here, the inputted set value can be one value, as shown in S 1220 a, or have an upper limit and a lower limit with a range, as shown in S 1220 b.
[0141] The switch controller 420 generates a switch control signal for controlling the on/off of the switch 430 according to the set value and applies the switch control signal to the switch 430 .
[0142] If one set value is inputted, as shown in S 1220 a, the output of the fuel cell (A) and the set value (B) are compared in S 1230 a. In case the output of the fuel cell is smaller than the set value (A<B), the duty ratio of the switch control signal is increased in S 1232 a, and if the output of the fuel cell is greater than the set value (A>B), the duty ratio of the switch control signal is reduced in S 1234 a. If the output of the fuel cell is equal to the set value (A=B), the current duty ratio of the switch control signal is maintained in S 1236 a.
[0143] In case the upper limit and the lower limit are inputted in step S 1220 b, the amount of hydrogen generation (A), the upper limit (B 1 ) and the lower limit (B 2 ) are compared in step 1230 b. If the amount of hydrogen generation is smaller than the lower limit (A<B 2 ), the duty ratio of the switch control signal is increased in step 1232 b, and if the amount of hydrogen generation is greater than the upper limit (A>B 1 ), the duty ratio of the switch control signal is reduced in step S 1234 b. If the amount of hydrogen generation is between the upper limit and the lower limit (B 2 =A=B 1 ), the current duty ratio of the switch control signal is maintained in S 1236 b.
[0144] By repeating steps S 2120 to S 1236 a or S 1236 b, the hydrogen generating apparatus 200 can generate the amount of hydrogen according to the inputted set value.
[0145] In the above method of controlling the amount of hydrogen generation, steps S 1120 to S 1136 a or 1136 b, or steps S 1220 to S 1236 a or 1236 b, can be written in a computer program. Codes and code segments, composing the program, can be easily realized by a computer programmer skilled in the art. Moreover, the program is stored in a computer readable medium, and realizes the method of controlling the amount of hydrogen generation by being read and run by a computer. The computer readable medium described above includes a magnetic recording medium, an optical recording medium and a carrier wave medium.
[0146] The drawings and detailed description are only examples of the present invention, serve only for describing the present invention and by no means limit or restrict the spirit and scope of the present invention. Thus, any person of ordinary skill in the art shall understand that a large number of permutations and other equivalent embodiments are possible. The true scope of the present invention must be defined only by the ideas of the appended claims. | A fuel cell power generation system including: a hydrogen generating apparatus, controlling an amount of hydrogen generation by controlling an on/off status of a switch connected between electrodes; and a fuel cell, being supplied with hydrogen generated by the hydrogen generating apparatus and producing a direct current by converting chemical energy of the hydrogen to electrical energy. The hydrogen generating apparatus used in the system preferably includes an electrolyzer, filled with an aqueous electrolyte solution containing hydrogen ions; a first electrode, accommodated in the electrolyzer, submerged in the aqueous electrolyte solution, and generating electrons; a second electrode, accommodated in the electrolyzer, submerged in the aqueous electrolyte solution, receiving the electrons to generate hydrogen; a switch, located between the first electrode and the second electrode; a meter, measuring an amount of hydrogen generation or an output of a fuel cell; and a switch controller, receiving a set value, comparing the amount of hydrogen generation or the output of the fuel cell measured by the meter with the set value, and controlling an on/off status of the switch. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. application Ser. No. 13/802,580, now U.S. Pat. No. 8,672,374.
BACKGROUND OF THE INVENTION
Tablet display devices have become popular consumer products for use in a variety of applications. Many such devices are flat, thin computers with a display panel on most of the area of one surface. Although the majority of these incorporate the computational, communication and display circuitry of a general purpose computer, some are more specialized for limited functionality, such as readers for electronic books or special map or industrial data displays. Typical dimensions are 8 in×10 in×½ in (similar to a tablet of paper) and 8 in×6 in×⅓ in (for so-called “mini” tablets), with weights ranging from about 2 pounds to just over ½ pound.
Wireless telephone communication devices with computer circuitry, known as “smartphones” have similar relative dimensions, but on a smaller scale. A growing trend has been to offer smaller tablets on the one hand and larger smartphones on the other, so that the sizes of the respective devices may converge. As used herein, the term “tablet computer” shall refer to any thin handheld device with a display panel on one surface and circuitry to generate a display on that surface.
Many uses involve operating the tablet computer while standing. While a tablet is light enough to hold in the hand, using it for any length of time may be tiring. A touch screen is operated with the fingers of the dominant hand, while the tablet is grasped with the other hand by its edge. The weight of the unit is applied to a moment arm that makes the user's grip difficult to maintain for an extended period of time. The tablet computer usually has a flat back that can be supported on the open palm of the off hand, but balancing the device is difficult while the touch screen is being activated.
The present invention addresses a need for a convenient way to hold a tablet computer in one hand while activating it with the other.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a compact and convenient way to hold a tablet computer in one hand while activating and using the device with the other hand. The device, as seen in FIG. 1 , is a small grip and stand that is to be attached at the approximate center of the tablet on the back, or underneath, side. In one embodiment, it is removably attachable to the tablet, and can serve as a handle or a small stand that elevates the tablet at a slight angle. A stem connects a base portion attached to the tablet and a top portion. A central hole of appropriate size in the stem accommodates a finger inserted through the grip. Opposing walls of the stem are biconcave in the plane perpendicular to the plane of the hole in the stem, defining a shape convenient for gripping between two fingers.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a perspective view of one embodiment of the invention;
FIG. 2 shows an end view of the embodiment of FIG. 1 ;
FIG. 3 shows an end view of the embodiment of FIG. 1 ;
FIG. 4 shows a side view of the embodiment of FIG. 1 ;
FIG. 5 shows a position of a user's hand when using an embodiment of the invention;
FIG. 6 shows an alternative position of a user's hand when using the embodiment of FIG. 6 ;
FIG. 7 shows a cross section through the center of the embodiment of FIG. 1 ;
FIG. 8 is a perspective view showing a cavity in the base of an embodiment of the invention;
FIG. 9 shows an embodiment of the invention that uses a tablet back cover to secure the holder to the tablet, with the holder and cover separated;
FIG. 10 shows the embodiment of FIG. 9 with the holder in place in the back cover;
FIG. 11 shows an embodiment of the invention with a design disc in place.
FIG. 12 shows an embodiment of the invention that uses a clip mechanism to attach the holder to the tablet.
FIG. 13 shows a top view of a retainer ring used in the embodiment shown in FIG. 12 .
FIG. 14 shows a cross section of the base of the embodiment shown in FIG. 12 , with a cross section of the retainer ring.
FIG. 15 shows a cross section of the base of the embodiment shown in FIG. 12 with the attachment unit in place.
FIG. 16 shows one version of an attachment unit for use with the embodiment shown in FIG. 12 .
FIG. 17 shows a different version of an attachment unit for use with the embodiment shown in FIG. 12 .
DETAILED DESCRIPTION
One embodiment of the invention is shown in FIGS. 1-3 . The holder 1 comprises a base 10 , a top 2 , and a pair of vertical support elements, 3 and 4 , connecting the base 10 with the top 2 . The top 2 has a lower surface 5 and an upper surface 6 . The base has a lower surface 7 and an upper surface 8 . The vertical support elements have facing inner surfaces 11 and 13 and outwardly facing surfaces 12 and 14 . Each also has outwardly facing surfaces 15 and 16 in a plane orthogonal to the plane of inner surfaces 11 and 13 . See FIG. 4 .
In this embodiment, the interior surfaces of the top, bottom, and sides define a generally-circular aperture space 9 sized to accept the insertion of a finger. The user can insert his finger with his palm toward the tablet, as in FIG. 5 , or away from the tablet. A diameter of about 0.9 in is a good compromise for the size of aperture 9 , but other dimensions may be desirable in particular applications. For example, it may be advisable to create three or more standard apertures to accommodate the different hand sizes of men, women and children.
As may be seen in FIGS. 1-4 , the vertical support elements 3 and 4 are curved inward in three directions, appearing as a triconcave pillar connecting the base and the top. The vertical support elements 3 , 4 are concave in the plane of the finger aperture 9 , each combining with the inner surface 5 of the top 2 and inner surface 8 of base 10 to define an approximate circle. In the plane perpendicular to the plane of the finger aperture, the vertical support elements are biconcave, defining back to back approximate half circles 17 , 18 perpendicular to the finger aperture 9 with approximate diameters slightly larger than that of the finger aperture. The user may grasp the holder between two fingers, partially encased by the half circles, to comfortably support the tablet with one hand. See FIG. 6 . In an embodiment, the outwardly facing surfaces 12 and 14 in the plane of the finger aperture 9 are relatively straight. These surfaces may take any shape consistent with the need for structural support of the top 2 .
The holder device is attachable to the back of a tablet computer, and preferably is removably attachable. In one embodiment, attachment is accomplished using a pair of magnetic discs. See FIGS. 7 and 8 . A holder magnet 25 is affixed in a cavity 21 in the base 10 of the holder device. The cavity 21 is just deep enough to envelop both the holder magnet 25 and a tablet magnet 26 affixed to the back of the tablet. In an embodiment, the base 10 is circular and the holder magnet 25 and the tablet magnet 26 are circular discs, a configuration that permits easy orientation of the finger aperture 9 when the holder is attached to the tablet.
In an embodiment, the holder magnet 25 and tablet magnet 26 are plated magnetic discs, each about 0.125″ thick, with attracting poles directed toward each other, providing a strong bond that can be broken with the deliberate application of moderate force. In another embodiment, the holder magnet 25 is a strong magnetic disc and the tablet attachment component 26 is a 16 gauge polished steel disc or a magnetic metal of suitable thickness. Known pressure sensitive adhesive tapes or materials may be used to affix the tablet attachment disc to the back of the tablet computer without damaging the tablet.
Attachment of the holder to the computer tablet may alternatively be accomplished in many other ways. FIGS. 9 and 10 , for example, show a back cover 35 with an aperture 36 through which the holder 1 is removably inserted. In this embodiment, when the holder 1 is not in place, the cover 35 could conveniently remain on the tablet without distorting the tablet's thin profile. It may be noted that in the illustration, the top of the holder comprises an alternative configuration to the curved top shown in other embodiments.
A different embodiment of the invention is shown in FIGS. 12-17 . In this embodiment, an attachment unit comprising a base with a plurality of vertical tines fits into a cavity in the base of the holder. As seen in FIG. 12 , holder 1 has a cavity 21 in base 10 . Instead of a magnet, a retainer ring 41 is inserted into the top portion of cavity 21 and affixed. The retainer ring 41 has an angled retainer ledge 42 around its inside surface, with a slight downward angle. Although one embodiment includes an inserted ring 41 , which is convenient for placement in units configured to accommodate a holder magnet 25 , as shown in FIG. 7 , it also may be desirable to fabricate a holder having an angled retainer ledge integral with the unit.
As shown in FIGS. 16 and 17 , attachment unit 50 comprises a base 43 and a plurality of vertical tines 44 . Each tine 44 has an engagement lip 45 at its free end. Engagement lip 45 has a slight upward angle to match the angle of angled retainer ledge 42 on retainer ring 41 in base 10 of the holder. This locks the attachment unit 50 and the holder 1 together, as illustrated in FIG. 15 . The tines 44 may be made of plastic or another material that affords slight flexure when force is applied at the tip so that they slide past the angled retainer ledge 42 when pressed into the cavity 21 of the holder and can be pulled away from the retainer ring 41 with the application of moderate force. Preferably the flexure of the tines 44 will also allow a user to rotate the orientation of the holder when the engagement lips 45 and the angled retainer ledge 42 are engaged.
Attachment unit 50 may be affixed to the back of the tablet device, using glue or other suitable adhesive, and holder 1 may then be attached and removed as needed. Alternatively, attachment unit 50 may be affixed to the tablet in a manner similar to that shown in FIGS. 9 and 10 , wherein the base 43 is held in place by a tablet cover that has an aperture 36 larger than the diameter of the tines 44 but smaller than the diameter of the base 43 . An attachment unit designed for use with a tablet cover will be dimensioned so that the length of the tines protruding past the tablet cover is long enough to permit engagement with the retainer ring in the holder.
The holder device may be fabricated or constructed of a variety of materials, with polymers or plastics particularly suitable. In an embodiment, a hard plastic molded endoskeleton 31 is enveloped by a softer plastic or polymer overmold 32 . The overmold skin, which in one embodiment is about 0.02 in thick, can be clear, revealing the endoskeleton, or any of a variety of colors. The skin may be seamless and sanitizable, for use in clean environments such as medical operating rooms. In some embodiments, the endoskeleton 31 may be configured to hold a dime-sized disc 33 that may incorporate a printed, engraved or embossed design or logo. See FIG. 11 .
The foregoing description has been presented and is intended for the purposes of illustration and description. It is not intended to be exhaustive nor limit the invention to the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application and to enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed for carrying out the invention. | A grip for holding a tablet computer in one hand while activating and using the device with the other hand comprises a stem connecting a base portion attached to the tablet and a top portion, with a central hole of appropriate size in the stem to accommodate a finger inserted through the grip. Opposing walls of the stem are biconcave in the plane perpendicular to the plane of the hole in the stem, defining a shape convenient for gripping between two fingers. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to compliant hydrodynamic fluid film bearings. The long life and low friction performance of compliant hydrodynamic fluid film bearings in ultra-high speed applications and in hostile environments which preclude the use of conventional lubrication has been attracting increasing interest among experts in the bearing art. One advantage of bearings of this nature, which has not been appreciated in the art however, is the potential cost savings which can be realized by the use of these bearings, instead of conventional bearings, in ordinary consumer products.
In this connection, factors which affect the economics of high volume manufacture and assembly and which have hitherto received scant attention in the fluid bearing art become important economically. In high volume products, where the cost of the individual bearing and the labor cost in assembling the product are significant, it is desirable that the assembly of the bearing in the product be fast, uncomplicated, and "fool proof" as possible. In addition, for the sake of simplicity of supply assembly, and inventory control, it is desirable that the number of individual parts from which the bearing is assembled be kept low. Finally, for ease of assembly and repair, the bearings should be interchangeable so that the bearing can be removed and replaced if it is or becomes damaged.
SUMMARY OF THE INVENTION
Accordingly, the objects of this invention are to provide a compliant hydrodynamic fluid bearing which is economical to manufacture and assemble in the product. The bearing can be formed of identical modules, requiring only a single inventory item, and the same bearing design can be used to produce a family of bearings having a range of bearing load capacity and stiffness.
Many of the background factors, objects and advantages of the invention of this application relate also to my co-pending application filed concurrently herewith, application Ser. No. 974,259 entitled "Hydrodynamic Compliant Thrust Bearing", the disclosure of which is incorporated herein by reference.
This invention contemplates the use of a single bearing element having both resilient supporting structure and a flexible compliant bearing sheet. The single module can be assembled in sections to produce a composite bearing wherein the resilient supporting member underlies and supports the bearing sheet member of the preceding bearing module, or the entire bearing can be made from a single module in which the bearing sheet member completely overlies the resilient underlying support member to which it is connected at one end.
DESCRIPTION OF THE DRAWINGS
These and other objects of the invention, and the invention itself, will become better understood by reference to the attached description of the preferred embodiments when read in connection with the accompanying drawings, wherein:
FIG. 1 is a perspective view of a bearing module in accordance with this invention;
FIG. 2 is a sectional elevation of the bearing module shown in FIG. 1 assembled in a bearing cartridge;
FIG. 3 is a perspective view of a second embodiment of this invention made in the form of a journal bearing;
FIG. 4 is a perspective view of a third embodiment of this invention made in the form of a journal bearing;
FIG. 5 is a perspective view of a fourth embodiment of this invention made in the form of a conical thrust bearing.
FIG. 6 is a perspective view of a fifth embodiment of this invention made in the form of a journal bearing assembled from a plurality of identical modules;
FIG. 7 is a perspective view of a sixth embodiment of this invention made in the form of a thrust bearing assembled from a plurality of identical modules; and
FIG. 8 is a developed sectional elevation of the thrust bearing shown in FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to the drawings, wherein like-reference characters designate identical or corresponding parts, and particularly to FIGS. 1 and 2 thereof, a unitary compliant hydrodynamic journal bearing member is shown separately (in FIG. 1) and in assembled form in a bearing cartridge, supporting a rotating shaft (in FIG. 2). The compliant hydrodynamic bearing is a composite assembly including a resilient supporting element and an attached overlying bearing sheet. This composite bearing lines the inside of the bearing sleeve, or the face of the thrust plate, and is in bearing relationship to the shaft or thrust runner which, according to compliant bearing theory, is supported on a hydrodynamic fluid film generated by the relative movement of the shaft or thrust runner over the bearing sheet. The compliance of the supporting element underlying the bearing sheet enables it to deflect to assume the optimum shape relative to the opposing bearing surface to produce the maximum supporting fluid pressure and distribution. It also enables the bearing sheet to conform, to some extent, to misaligned and thermally distorted shafts and thrust runners. The supporting element is more compliant than the fluid film so it will deflect before the fluid film is breached.
In the embodiment of FIGS. 1 and 2, the composite bearing assembly is formed of a single continuous module consisting of a sheet of flexible metal, such as stainless steel, having a first section 10 formed in a regular series of raised resilient sections 12 presenting a corrugated appearance. A second continuous section 14, integral with the first section 10, has a smooth inside bearing surface 16 which may be coated with an antifriction coating, such as "MolyKote" or "HL-800," proprietary antifriction coatings of Hohman Plating and Manufacturing Company and Mechanical Technology Incorporated, respectively. Bearings experiencing only moderate temperatures can use Teflon as the anti-friction coating.
The composition and method of application of the "HL-800" coating is disclosed in the copending application Ser. No. 974,264 entitled "High Temperature Low Friction Surface Coating", of Bharat Bhushan filed concurrently herewith, the disclosure of which is hereby incorporated by reference. These coatings are used primarily in applications in which the lubricating fluid is a gas, such as air or helium. If the gas film of a gas bearing is breached and high speed contact between the relatively rotating bearing members occurs, damage can result. In addition, during start-up or slow-down or the rotor, the rotor's bearing surface is supported directly by the bearing surface 16, so it is desirable to coat the surface with a solid lubricant film to provide lubrication during these phases of operation when the hydrodynamic effect is not operating.
The area between the raised elevations 12 on the corrugated section 10 is formed in flat lands 18. These flat lands, or the entire upper and lower surfaces of the first section 10 and the outside surface 19 of the smooth section 14, opposite the inside surface 16 may be coated with a friction-enhancing material and/or textured as by electrolytic etching to produce a friction-enhancing surface texture. The friction-enhancing materials and/or texturing are selected to optimize the frictional properties of the surfaces in order to yield the degree of coulomb damping best suited for the particular application.
In use, the bearing is rolled up in the direction shown by arrow 20 to form a two-layer roll, with the smooth section 14 forming the inner layer of the roll, as shown in FIG. 2, with the inside surface 16 facing inwardly, and is fastened to the wall of a bearing sleeve 24, as by welding at 21. A shaft 22 is inserted in the bearing with its circumferential surface in bearing relationship with the surface 16. The flat lands 18 on the corrugated section 10 bear against the inner wall 26 of the bearing sleeve 24 and the peaks of the raised resilient sections 12 bear against and support the outside face 19 of the smooth section 14.
A second embodiment of the invention, shown in FIG. 3, is a single bearing module employing an elastomer mat 30 having molded resilient projections 32 corresponding in form and function to the projections 12 of the first section of the embodiment shown in FIG. 1. A flat, flexible metal sheet 34 is integrally molded at one end in one end of the elastomer mat 30 to provide a unitary bearing module which can be rolled up in a manner corresponding to that shown in FIG. 2, and inserted in a journal bearing sleeve with the top surface 36 of the flexible sheet 34 facing inwardly towards the shaft and resiliently supported by the resilient projections 32 of the elastomer mat section 30. Although the first and second sections are connected together, they are formed of separate pieces. Therefore, the projections 32 may be considered to be discontinuous from the bearing sheet 34. This enables the characteristics of each section to be individually optimized for the particular requirements of the bearing. The end of the metal sheet 34 may be dimpled, perforated and/or textured to ensure a strong and permanent bond between the metal sheet 34 and the elastomer mat 30. The elastomer section may be fastened to the journal bearing sleeve with cement, and the sheet 34 is left free at the leading edge, as in FIG. 3, to give the necessary freedom of movement in operation.
The embodiment of the invention shown in FIG. 4 is a single bearing module consisting of a sheet of flexible metal having a first section 40 in which are formed, as by stamping, raised projections 42 in the form of bumps, each split longitudinally along its crest and extending laterally across the length of the sheet. The other half 44 of the sheet is flat and includes an upper surface 46 which constitutes the bearing surface facing the shaft when the sheet is rolled up in the same manner as the embodiments of FIGS. 1 and 3, as indicated in FIG. 2. Although the first and second sections are formed of a single sheet of metal, the crest of each projection 42 terminates in a pair of free edges which can be considered discontinuous with the bearing sheet 44. This enables the projections to deflect independently without causing circumferential movement of the module as a unit. The bearing surface 46 may be coated with a friction reducing material such as "HL-800," and the other surfaces may be coated or treated to optimize their frictional properties, as mentioned previously.
Turning now to FIG. 5, a unitary overlapping conical compliant fluid bearing having both thrust and radial load capacity consists of a single bearing module as is shown in this perspective view. Typically, another conical bearing assembly, the mirror image of that shown in FIG. 5, will be located at the other end of the shaft to bear radial loads at that end and also axial loads in the other direction. The module includes a resilient section 50 in which spaced resilient projections 52, of alternating length for axial uniformity of stiffness, are formed in the same manner as in FIG. 4 for supporting an overlying smooth section 54, which is formed integrally on the end of the resilient support section 50. This embodiment of the invention is in the form of a broad, helical tape having a central bore 58. The upper surface (shown facing down in FIG. 5) of the smooth section 54 may be coated with a suitable friction reducing coating, such as the aforementioned "HL-800," to reduce start-up torque, and to prevent galling in the case of high speed touch down. The module should be fastened, as by welding, to its conical bearing cartridge, preferably at the trailing edge, or at the junction between the smooth section 54 and the support section 50, to permit relative movement of the smooth section 54 and the supporting section 50 during operation, and to prevent the tape from wrapping around and gripping the conical end of the rotor in the manner of a band brake or spring clutch.
Referring now to FIG. 6, another aspect of the invention is shown wherein the unitary bearing member is formed of a plurality of separate identical modules which can be assembled and fastened together in an integral form either prior to, or at the same time, the entire bearing is assembled in its bearing cartridge. The individual bearing modules each include a first molded elastomer mat section 60 having a series of resilient projections 62 formed on one surface thereof for resiliently supporting the second section 64 of the module which is a smooth, flexible sheet of bearing material, such as stainless steel, attached to or near the end of the first section 60. The support sections 60 each have a length equal to an integer fraction of the inner circumference of the bearing sleeve and the composite bearing is assembled in a number of sections, the combined length of whose sections 60 just equals the internal circumference of the bearing sleeve or cartridge. When the number of support sections is one, as in the embodiment of FIG. 3, the integer fraction is 1/1; when two or three modules are used it will be 1/2 and 1/3 , respectively. The assembled strip is then rolled in a cylindrical roll, and the two ends are fastened together in the same manner that the individual modules were fastened together to form the strip. In the particular embodiment of FIG. 6, the fastening together is by way of a plurality of mushroom-shaped or dovetailed projections 66 extending from one end of the module, which fit into corresponding mushroom-shaped recesses 68 on the other end of the first section 60 of each module, so that the flexible sheet 64 overlies the resilient section 60 of the succeeding adjacent module. The resulting assembly of bearing modules is a unitary cylindrical structure which is self-contained and can be inserted in its assembled form in the bearing sleeve without further need of supporting structure. Suitable tabs may be formed on the first section 60 to fit into corresponding slots in the bearing sleeve and/or the assembly may be cemented in the sleeve to prevent the bearing assembly from rotating within or otherwise moving relative to the bearing sleeve.
Referring now to FIG. 7, a thrust bearing assembly is formed of individual, identical bearing modules, each of which includes a resilient support or first section 70 formed in a pattern of resilient projections in the form of longitudinally split bumps 72 similar to those in FIG. 4. The resilient support section 70 supports a second or smooth section 74 of the preceeding or downstream module, in the direction of rotation of the thrust runner. Each module forms a half circle, half of which is resilient projections 72 and half of which is smooth section 70 having a smooth upper surface 76. If more pads, for example six pads, are used, each module would equal about 120° or 360° divided by one-half the number of pads. The leading edge of the smooth section 74 of each module is fastened to a spacer block 77 along the radial center line of the module, and the spacer block is welded to the thrust plate 78 to secure the module in place. Alternatively, the spacer block 77 may be provided with downwardly bent tabs 79 that fit into grooves 80 in the thrust plate 78. The split bumps 72 on the end of the resilient section 70 lie parallel to but ending short of the radial center portion of the preceding module. Thus, the modules do not suffer distortion in operation, because the terminal edge of the resilient section is free to move under thermal expansion, and the split bump projections 72 can flex independently of the module as a whole when the bearing sheet section 74 conforms to the bearing surface of the rotating thrust runner 82 in the event of thermal distortion or runner runout during operation.
The assembled bearing, from the top, displays the appearance of a plurality of flaps formed of bearing material having smooth upper surfaces which face the thrust runner 82. The smooth bearing flaps 74 are supported by the underlying resilient sections 70 of the succeeding module in the direction of rotation of the thrust runner. The amplitude and period of the corrugations 72 can be adjusted when the modules are manufactured to provide the optimum lead-in and resilience for the generation of the hydrodynamic supporting fluid wedges. As shown in FIG. 8, the corrugations can be of low amplitude and wide wave length at the beginning of the corrugated section, and change gradually to higher amplitude and shorter wave length to give an overall wedge-shaped outline to the supporting resilient section 70 and a suitable stiffness to the support at the portions of the resilient support where it is needed.
The modules shown in FIGS. 7 and 8 could be made without the spacer blocks 77, as illustrated by the rightmost module in FIG. 8. In this embodiment, the module would be welded at 84 on the flat land portion after the last or trailing bump 70. Alternatively, the modules could be made folded over 180° with the spacer block 77 in the fold. In this way the smooth section 74 would overlie and be supported by its own support section 70. In this modification the thrust runner 78 would rotate in the direction opposite to that indicated by the arrow in FIG. 7.
The embodiments of the invention shown herein facilitate low cost fabrication and assembly techniques because the bearing modules are suited for high volume, low cost fabrication and the inventory problems are minimized because the bearings in each case are formed of unitary identical parts. The unitary construction permits great simplification of the manufacture and assembly of the bearing, and also greatly simplifies the inventory logistics of large volume operations. Any replacement of bearings of this variety that may be necessary is easy and inexpensive. The replacement cost is trivial and the assembly of the replacement bearing, in the case of the journal and conical bearings, is simply a matter of rolling up the unitary bearing member and inserting into its cartridge. In the case of the thrust bearing, it is simply a matter of dropping the replacement bearing assembly into the grooves in the thrust plate. As new materials and other bearing construction details are developed, they may be incorporated into the bearing without necessitating a redesign of the apparatus, and the replacement bearings for existing apparatus may incorporate the new designs.
Obviously, numerous modifications and variations of the disclosed embodiments of the invention are possible in view of the above-disclosure. | A resilient, compliant, hydrodynamic fluid film bearing, for positioning between a stationary member and the bearing surface of a rotor, includes a bearing module formed as a unitary one-piece article having a resilient support section and a bearing surface section which overlaps its own resilient support section, or that of the next adjacent module, to provide a low cost bearing which is easy, fast and economical to manufacture and assemble. | 5 |
BACKGROUND OF INVENTION
This invention relates generally to refrigerators, and more specifically, to controlling humidity in a refrigerator fresh food compartment.
At least some known refrigerators regulate the temperature of the fresh food compartment by opening and closing a damper established in flow communication with a freezer compartment, and by operating a fan to draw cold freezer compartment air into the fresh food compartment as needed to maintain a desired temperature in the fresh food compartment. The temperature of the evaporator surface in the freezer compartment is typically much lower than the air temperature in the fresh food compartment. This drives moisture from the fresh food compartment to the freezer compartment where it mostly freezes on the evaporator surface. This reduces the relative humidity in the fresh food compartment. Relative air humidity in the fresh food compartment of the refrigerator has a high influence on the fresh food quality. Deterioration of some foods such as vegetables, fruits, mushrooms, bread, and the like in a low humidity environment is rapid and irreversible.
As is well known with humidors, freshness of items that are stored at room temperatures is readily accomplished merely by sealing a storage container to prevent the entry of air. This is not effective, however, in a refrigerated environment where temperatures are maintained well below a normal room temperature of, for instance, 70 degrees. In known refrigerators, maintaining fresh food quality is a challenge. While covered crisper pans and meat storage pans are typically provided in the fresh food compartment to retard the drying out of items placed therein, there is no provision for controlling the relative humidity of the remainder of the fresh food compartment of the refrigerator.
SUMMARY OF INVENTION
In one aspect, a refrigerator includes a refrigerating compartment configured to preserve food, the compartment including a plurality of walls forming a cavity, a door coupled to the compartment configured to cover the cavity when in a closed position, and a passageway positioned on at least one of the walls and the door such that air within the cavity is in flow communication with air outside the cavity when the door is in the closed position.
In another aspect, a refrigerator includes a refrigerating compartment configured to preserve food, the compartment including a plurality of walls forming a cavity, a door coupled to the compartment configured to cover the cavity when in a closed position, and a gasket positioned between the compartment and the door when the door is in the closed position, and a passageway positioned in the gasket such that air within the cavity is in flow communication with air outside the cavity when the door is in the closed position.
In another aspect, a refrigerator includes a refrigerating compartment configured to preserve food, the compartment including a plurality of walls forming a cavity, a door coupled to the compartment configured to cover the cavity when in a closed position, and a user interface operationally coupled to the cavity, the interface configured to receive a relative humidity setting, and maintain the relative humidity within the cavity about the received relative humidity setting by controlling an exchange of outside air with the cavity.
In another aspect, a method for manufacturing a refrigerator includes forming a refrigerating compartment configured to preserve food, the compartment including a plurality of walls forming a cavity, coupling a door to the compartment such that the door covers the cavity when in a closed position, and coupling a passageway to at least one of the cavity and the door such that air within the cavity is in flow communication with air outside the cavity when the door is in the closed position.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of a refrigerator.
FIG. 2 is a partial perspective view of an exterior surface of the refrigerator of FIG. 1 .
FIG. 3 is a cross sectional view of a refrigerator sidewall including a passageway.
FIG. 4 is a cross sectional view of a refrigerator sidewall including another embodiment of a passageway.
FIG. 5 is front perspective view of a refrigerator with a control interface.
FIG. 6 is a cross sectional view of a refrigerator side wall with an automatically controlled vent.
DETAILED DESCRIPTION
FIG. 1 illustrates an exemplary side-by-side refrigerator 100 . It is contemplated, however, that the teaching of the description set forth herein is applicable to other types of refrigeration appliances, including but not limited to top and bottom mount refrigerators where humidity control in the fresh food compartment is desirable. The present invention is therefore not intended to be limited to any particular type or configuration of a refrigerator, such as refrigerator 100 .
Refrigerator 100 includes a fresh food storage compartment 102 and freezer storage compartment 104 , an outer case 106 and inner liners 108 and 110 . A space between case 106 and liners 108 and 110 , and between liners 108 and 110 , is filled with foamed-in-place insulation. Outer case 106 normally is formed by folding a sheet of a suitable material, such as pre-painted steel, into an inverted U-shape to form top and side walls of case 106 . A bottom wall of case 106 normally is formed separately and attached to the case side walls and to a bottom frame that provides support for refrigerator 100 . Inner liners 108 and 110 are molded from a suitable plastic material to form freezer compartment 104 and fresh food compartment 106 , respectively. Alternatively, liners 108 , 110 may be formed by bending and welding a sheet of a suitable metal, such as steel. The illustrative embodiment includes two separate liners 108 , 110 as it is a relatively large capacity unit and separate liners add strength and are easier to maintain within manufacturing tolerances. In smaller refrigerators, a single liner is formed and a mullion spans between opposite sides of the liner to divide it into a freezer compartment and a fresh food compartment.
A breaker strip 112 extends between a case front flange and outer front edges of liners. Breaker strip 112 is formed from a suitable resilient material, such as an extruded acrylo-butadiene-syrene based material (commonly referred to as ABS).
The insulation in the space between liners 108 , 110 is covered by another strip of suitable resilient material, which also commonly is referred to as a mullion 114 . Mullion 114 also preferably is formed of an extruded ABS material. It will be understood that in a refrigerator with separate mullion dividing an unitary liner into a freezer and a fresh food compartment, a front face member of mullion corresponds to mullion 114 . Breaker strip 112 and mullion 114 form a front face, and extend completely around inner peripheral edges of case 106 and vertically between liners 108 , 110 . Mullion 114 , insulation between compartments, and a spaced wall of liners separating compartments, sometimes are collectively referred to herein as a center mullion wall 116 .
Shelves 118 and slide-out drawers 120 , 121 normally are provided in fresh food compartment 102 to support items being stored therein. A bottom drawer or pan 122 partly forms a quick chill and thaw system (not shown in FIG. 1 ) selectively controlled, together with other refrigerator features, by a microprocessor (not shown) according to user preference via manipulation of a control interface 124 mounted in an upper region of fresh food storage compartment 102 and coupled to the microprocessor. Shelves 126 and wire baskets 128 are also provided in freezer compartment 104 . In addition, an ice maker 130 may be provided in freezer compartment 104 .
A freezer door 132 and a fresh food door 134 close access openings to fresh food and freezer compartments 102 , 104 , respectively. Each door 132 , 134 is mounted by a top hinge 136 and a bottom hinge (not shown) to rotate about its outer vertical edge between an open position, as shown in FIG. 1 , and a closed position (not shown) closing the associated storage compartment. Freezer door 132 includes a plurality of storage shelves 138 and a sealing gasket 140 , and fresh food door 134 also includes a plurality of storage shelves 142 and a sealing gasket 144 .
FIG. 2 is a partial view of door 134 and the exterior sidewall 250 and top 260 of fresh food compartment 102 of refrigerator 100 . Rear panel 270 is opposite door 134 . Shown in sidewall 250 is a sizing member 210 which is partially obstructing a passageway 204 which is shown in more detail in FIGS. 3 and 4 . Passageway 204 extends from inner panel 108 to outer case 106 in sidewall 250 and connects fresh food compartment 102 to outside air through a plurality of openings 220 which may be positioned on outer case 106 of sidewall 250 as shown in FIG. 2 or on inner liner 108 as shown in FIG. 3 . In one embodiment, a filtering member 230 is positioned within passageway 204 . In another embodiment, filtering member 230 is adjacent passageway 204 . In another embodiment, a plurality of louvers 240 are positioned at one end of passageway 204 . Sizing member 210 is positioned on either the refrigerator exterior as shown in FIGS. 2 and 3 or the interior as depicted in FIG. 4 .
Humidity control in fresh food compartment 102 is achieved by the controlled communication of outside air with fresh food compartment 102 through passageway 204 . Sizing member 210 is movable to allow adjustment of air flow through passageway 204 . In one embodiment, sizing member 210 is user adjustable. In another embodiment, sizing member 210 is automatically moved. Filtering member 230 facilitates keeping foreign particles from entering fresh food compartment 102 through passageway 204 . In another embodiment, louvers 240 facilitate keeping foreign particles from entering fresh food compartment 102 . Though shown on the sidewall 250 of refrigerator 100 , in FIG. 2 , in an alternative embodiment, passageway 204 is located on the refrigerator top 260 or rear panel 270 or in refrigerator door 134 . Passageway 204 can be of any shape and can extend linearly as shown in FIGS. 3 and 4 or could extend at least partially arcuately between inner liner 108 and case 106 . In another embodiment, passageway 204 is positioned on sealing gasket 144 .
FIG. 5 illustrates a control interface 324 of refrigerator 100 . Interface 324 includes a humidity sensor 340 that senses the relative humidity of the air inside fresh food compartment 102 , and a display panel 330 that numerically displays the sensed value. In addition to humidity control, other control features associated with the refrigerator may be incorporated into control interface 324 .
Control interface 324 provides for automatic operation of the humidity control system. In FIG. 6 , automatic vent 400 is shown within a side wall of refrigerator between inner liner 108 and outer case 106 . Vent 400 includes a damper 410 positioned in passageway 204 and an actuator such as servomotor 420 . Damper 410 is pivoted at pivot end 412 and is movable to open and close vent 400 by opening and closing air passageways 430 in the outer case. Damper 410 is connected to servomotor 420 by an actuating rod 414 . Servomotor 420 , controlled by the refrigerator control system, opens and closes the vent passage 400 based on the humidity level detected by sensor 340 and a humidity level selected by the user through an adjustment dial 350 . For example, control interface 324 receives a relative humidity setting from a user and controls actuator 420 to maintain the humidity level in fresh food compartment 102 about the selected humidity level. In one embodiment, the relative humidity is maintained within 2% of the received setting. That is, for a selected setting of 70%, the relative humidity within fresh food compartment 102 is maintained within the range of 68% to 72%. In another embodiment, the relative humidity is maintained within 4% of the selected level. Alternatively, in another embodiment, control interface 324 maintains the relative humidity within 8% of the selected level.
While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims. | A refrigerator includes a refrigerating compartment configured to preserve food, the compartment including a plurality of walls forming a cavity, a door coupled to the compartment configured to cover the cavity when in a closed position, and a passageway positioned on at least one of the walls and the door such that air within the cavity is in flow communication with air outside the cavity when the door is in the closed position. | 5 |
CROSS REFERENCE
The subject matter of this application is related to that of U.S. patent application 11/049,407 filed Feb. 2, 2005 (Brennan 8-87-11-54-10-6) filed contemporaneously and assigned to a common assignee which is hereby incorporated by reference in its entirety.
TECHNICAL FIELD
This invention relates to integrated circuits and in particular to integrated circuits with high aspect ratio wire bonds.
BACKGROUND OF THE INVENTION
Many integrated circuits, such as RF amplifiers, generate a substantial amount of heat during operation. For example, contemporary RF amplifiers used in wireless communication systems often operate at temperatures approaching 200 degrees C. Clearly at such elevated temperatures, an efficient approach to dissipating the generated heat is required. Thus the packaging for these integrated circuits is generally formed on a heat sink made of a material e.g. copper containing or aluminum containing composition that has excellent heat conducting properties, and the packaging materials are chosen to be resistant to heat degradation.
Many such packages therefore are formed on a metal base or heat sink, 1 , in FIG. 1 using materials such as alumina, 5 , to form package walls that surround the integrated circuit, 3 , forming a cavity package. The package walls provide mechanical and environmental protection to the integrated circuit. For hermetically sealed packages, a lid, typically metal or ceramic, is placed on top of the package after the integrated circuit is die bonded and wire bonded into the cavity region formed by the walls and subsequently sealed with a moisture impermeable material such as a metal or glass. For non-hermetically sealed packages the walls of the cavity package are used to form a dam for subsequent introduction of a polymer, 6 , that encapsulates the integrated circuit. (The integrated circuit body is generally referred to as a die.) Electrical connection to the device, e.g. die is formed from metal leads, 7 and the base or heat sink 1 . Wires are attached to the capacitor(s), 8 , die(s) and leads to make electrical contact. Wire loops with precision shapes are used for proper electrical performance. The die and capacitors are bonded to the base to form thermal and electrical connection to the base. After forming the electrical interconnections the alumina walls, 9 , are extended and an alumina cap, 10 , is provided.
For many ceramic based packages the material employed for the heat sink is a composite of copper and tungsten. This metallic material is advantageous since it has a coefficient of thermal expansion approximately matching that of the overlying alumina walls. (The coefficient of thermal expansion for copper/tungsten ranges from 6.2 to 6.5 ppm/° C.(room temperature to 500° C.) as compared to approximately 6.9 to 7.2 ppm C.(room temperature to 400° C.) for alumina. Since the copper/tungsten alloy and the alumina have matching coefficients of thermal expansion, differential thermal expansion induced stresses at interfaces between the different materials is small so that the resulting cavity package is relatively stable despite large temperature excursions.
At the same time there has been a continuous drive toward higher and higher electrical power density per device to increase integration and decrease size. Therefore, to maintain a safe operating temperature, the power dissipation the package must provide increases. Accordingly, it becomes desirable to replace the copper/tungsten heat sink with a material that has superior heat conducting properties. One material that is low cost, readily available, easily manufactured in complex shapes, and has a high thermal conductivity is copper. Although copper has a heat conductivity of approximately 391 W/mK, (as compared to approximately 176 W/mK for copper/tungsten), its coefficient of thermal expansion, approximately 17 ppm/C. (room temperature), is a poor match for that of alumina. Thus the use of a copper heat sink despite its improved heat transfer characteristics is precluded for use with alumina walls, unless the copper is embedded into the center of a Cu-W base or some other base material that compensates sufficiently for the coefficient of thermal expansion of alumina. A composite Cu/Cu-W structure is significantly more expensive than a single Cu or Cu-W base. In addition such composite structure is more prone to deformation, and concomitant less than optimum thermal performance when mounted into the system.
To allow use of a copper heat sink, a polymer rather than alumina walls are employed. Polymers such as liquid crystal polymers have a coefficient of thermal expansion matching that of copper and have relatively high melting points compared to other polymers. Such polymers are commercially available from, for example, Ticona Manufacturing-Headquarters, 8040 Dixie Highway, Florence, Ky. 41042 U.S.A., Ticona, GmbH D-65926 Frankfurt am Main. In particular the Vectra line of materials have temperature stability up to 370° C. (Melting temperature (10° C./min); Test Standard: ISO 11357-1,-2,-3.) Although liquid crystal polymers have suitable thermal properties, their coefficient of thermal expansion is anisotropic. That is, their physical properties such as the coefficient of thermal expansion vary with orientation. In general for liquid crystal polymers, the thermal coefficient of expansion in the direction the polymer was drawn during preparation (parallel direction) is generally in the range 3 to 10 ppm/C. (0.03×10 −4 /° C. ISO 11359-2) while the coefficient of thermal expansion in a direction perpendicular to the draw direction (normal direction) is relatively large, 15 to 25 ppm/C. (0.19×10 −4 /°C. ISO 11359-2). Thus if the polymer forming the package walls is all aligned in the appropriate direction, an appropriate match to the thermal expansion properties of copper is possible. Unfortunately, typically at least a portion of the walls in the region adjoining the copper heat sink generally has the lower rather than higher coefficient of thermal expansion in a direction parallel with the major surface of the heat sink due to the requirements of the injection process used to form the walls. Thus although strain due to thermal mismatch between liquid crystal polymer walls and a copper heat sink is substantially reduced relative to a similar structure with alumina walls, thermal mismatch issues still remain.
Even once materials for the package are chosen, the assembly of the package using those materials is not free from difficulties. The height and shape of the lead wires, 4 , in FIG. 1 are critical to tuning the RF response of the device. As the frequency of such devices increases, so does the height of these wire loops. Thus the height of walls, 5 , must be extended so that the polymer, 6 , introduced after the lead wires are connected, encapsulates such wires and prevents damage or a change in geometry.
FIG. 2 illustrates a wirebond tool head including wire clamps. The bonding tool is normally held vertically but wire clamps behind the tool are at an angle generally between 30 and 60 degrees. A tool shown at 22 in FIG. 2 is introduced, for example, to bond the wire, 21 , to the capacitor block. Such bonding is accomplished by introducing ultrasonic energy through the tool together with compression also induced by the tool. As shown in FIG. 2 , the height of the walls limits the angle at which it is possible to introduce the tool, 22 . The geometry at the edge, 23 , of the tool is chosen to accommodate this angle limitation. Generally an angle between 30 and 60 degrees has been employed. After the walls are positioned the wire bonds are formed and the remaining package is assembled.
Thus new packages employing copper heat sinks and polymer side walls have been introduced and solve many issues associated with high performance devices. However, improvement, as discussed, is certainly possible.
SUMMARY OF THE INVENTION
Surprisingly it has been found that the assembly process has been substantially compromised for devices including wire electrical interconnection loops with geometries having 1) a loop height to wire length aspect ratio greater than 2:1 for 2) a loop height greater than 10 mils. (Such geometry satisfying these two criteria are denominated high aspect ratio geometries in the context of this invention. The wire length is the distance along the wire between bonding points forming the electrical connection between the die and another component. The loop height is the distance measured normal to the major surface of the heat sink to the point on the wire furthest above this surface.) The angle limitations induced by the sidewalls compel a compromise in compression tool geometry that leads to unreliable bonds of the wire with the die, capacitor, and/or lead frame. Thus an expedient is required to avoid such problems in devices having this high aspect ratio geometry. In one embodiment to avoid this unexpected degradation, the sidewalls are either formed after wire bonding or the sidewalls are formed to a limited height that allows successful bonding and then extended to a height necessary for introduction of the encapsulating polymer and/or a lid that clears the wire loops. Thus, undesirable interaction between the tool and the package geometry is avoided and the required wire bond configuration is maintained while forming a satisfactory bond.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 through 3 illustrate construction of device packages.
FIGS. 4 and 5 are exemplary of structures involved in interaction between heat sink and walls.
FIGS. 6 through 12 illustrate a process for forming a device package.
DETAILED DESCRIPTION
Surprising results have been found for devices with 1) at least one lead wire having loop height to wire length aspect ratio greater than 2:1, especially greater than 5:1, and 2) a loop height greater than 10 mils, (i.e. a high aspect geometry in the context of this invention). In particular, the connection between such wire and the lead frame or other point of attachment such as capacitors external to the die are not expeditiously made and tend to suffer inadequate bonding. A number of techniques are possible for avoiding the difficulties induced in the wire bonding process. Generally, wire bonds for wires having high aspect ratio geometries should be made before forming on the heat sink walls with a height greater than the loop height used in the final device configuration. Generally, the maximum loop height varies from 10 mil to 60 mil. (The height of a wall is measured in a direction normal from the major surface of the heat sink it adjoins and the height is given by the median height so measured along the perimeter of the wall.)
The heat sink is generally formed of a metal such as copper or aluminum with a surface area in the range 25 mm 2 to 2500 mm 2 and a thickness in the range 5 mil to 100 mil. Although greater thicknesses and surface areas are not precluded, typically, those indicated are sufficient for dies having dimensions in the range 10 mm 2 to 2000 mm 2 . Generally a portion of the wall is formed around the perimeter of the heat sink for support of metal external leads. Typical materials for these walls are liquid crystal polymers (LCP). As discussed above, the height of this initial wall portion should be sufficiently small to allow a bonding tool having the desired tip angle to be used without interference. For high aspect ratio wires, wall heights less than 30 mils are generally employed before wire bonding. (Generally it is desirable to form the external leads on this insulating wall portion, but formation of the leads without completion of the wall perimeter is not precluded.) The wall is generally attached to the heat sink using stakes as shown in FIG. 6 at 61 . These stakes are typically formed of LCP and attachment at 71 as shown in FIG. 7 is generally accomplished by ultrasonic staking. In this bonding process ultrasonic energy in the range 45 mA to 65 mA is typically applied at 72 with a compressive force in the range 40 grams to 55 grams over an area in the range 1 mil to 7 mils. The external leads to which wires are attached for electrical connection to the die and/or a capacitor and/or other element of the package are introduced such as shown in FIG. 8 at 81 . In one advantageous method the leads 81 have openings that are fitted around the end 83 of stakes 71 leading to the configuration shown in plan view 85 . The leads are attached, for example, again using ultrasonic bonding in the previously described energy range applying compressive forces at 84 as discussed above. Alternatively, the walls are formed by a molding process such as described in co-pending, coassigned application 11/049,407 filed Feb. 02, 2005 (Brennan 8-87-11-54-10-6), as shown for example, in FIGS. 4 and 5 , and the lead frame is attached by injection molding to walls having a height generally less than 30 mils.
A die or dies are attached to the heat sink or to a structure communicating (e.g. thermally communicating) with such heat sink generally by employing methods such as eutectic die attachment with alloys such as AuSi or AuSn. Additionally, if desired, capacitors or other components such as discrete components are also attached to the heat sink or to a body overlying the heat sink by processes such as eutectic die attachment. Thus, as shown in FIG. 9 , dies 91 are attached to heat sink 90 . Electrical interconnections are made between and/or among the dies, the lead frame, and the capacitors or other components if present. Some of such possible wire interconnects are illustrated in FIG. 9 at 92 , 93 , and 94 . As discussed, by employing walls of height less than 30 mils before making high aspect ratio wire interconnects, wires are accommodated without degradation of the desired electrical interconnection.
Bonding of the wires at the lead frame, die, capacitor, or at other components present in the structure are formed typically using a tool denominated a wedge bond tool. It is preferred that bonding first be performed at the die and then at the external lead to facilitate as short a wire bond as possible from, for example, the die drain to the external lead. This tool has an angular end determined by the wire clamp mechanism where the bonding feed angle, angle 102 , as shown in the cross section of FIG. 10 at 101 , is typically in the range 38 to 45 degrees. Angles greater than 45 degrees lead to reduced loop profile process control while angles less than 38 degrees are unacceptable because the tool will interfere with package features. The wire 104 for forming the interconnect is introduced in the tool as shown at 102 and is bonded at the desired location by thermosonic compression bonding. A tool having an implementation angle in the range 38 to 45 degrees is employable with a resulting acceptable balance of resulting properties when the walls have a height less than 30 mils at the time of bonding. The process produces electrically viable, stable wire bonds.
The wall height is then increased such as shown in FIG. 11 so that such walls act as a suitable dam for introducing a polymer that encapsulates the previously formed wire bonds and/or supports a lid above the wire loops. These walls 112 are typically formed of polymer material, have a width 114 in the range 10 to 40 mils, and are attached to the leads 115 by ultrasonic welding. In one suitable configuration, a cavity for subsequent introduction of a lid is formed by employing member 116 around the perimeter of the walls. Typically this structure has a height in the range 15 mils to 65 mils and a width in the range 5 mils to 30 mils. Cavity fill material is then introduced to isolate the wires and dies as well as other components from contamination. Such fill materials are generally of the composition epoxy, acrylics or silicones and are introduced by liquid injection. A lid as shown in FIG. 12 is then advantageously used to seal the package. This lid is introduced in the previously formed cavity structured by members 116 and is attached either by a mechanical snap-in feature, by ultrasonic welding, or by a suitable adhesive. | Devices such as amplifiers are built on a heat sink having a perimeter wall surrounding active electronic devices. Surprisingly formation of wire bonds to such devices tends to be degraded if they have an aspect ratio greater than 2:1. This problem is overcome by forming wire bonds before such walls have a height of 30 mils and after bond formation extending the walls to their final height. | 7 |
RELATED APPLICATIONS
This application claims priority to U.S. Provisional Application No. 60/008,148, filed Oct. 31, 1995, the contents of which is incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
Assessment of tissue perfusion/ischemia is of critical importance in a number of medical applications. In plastic and reconstructive surgery it is used for postoperative monitoring of transplanted muscle flaps. A prerequisite for a successful operation and outcome is proper perfusion or passage of blood through the vascular bed of the transplanted tissue. It is essential to know as early as possible after surgery if the tissue is becoming ischemic, i.e., locally anemic due to some mechanical obstruction or other reason, and thus jeopardized. In this event, rapid surgical intervention can be used for corrective measures. A very similar application exists in cardiology where myocardium ischemia monitoring is of crucial importance. Also, measurement of ischemia in the legs due to arteriosclerotic plaque (or other reasons) is a problematic area. Monitoring and measuring ischemia levels during long "blood-less" reconstructive surgeries of arms and legs, where the blood perfusion is intentionally stopped to enable delicate surgery without significant blood loss, is of significant importance as an indicator of the patient's well being.
There are numerous methods for monitoring muscular perfusion. Techniques that image the vasculature directly include: Doppler, duplex scanning, angioscopy, and arteriography. Indirect methods include: pH measurements, transcutaneous PO 2 monitoring, laser Doppler, and fluorescein staining.
Each of these techniques, however, has its attendant drawbacks. Doppler monitoring and duplex scanning operate by detecting the flow of blood though the tissue or arteries in question. The equipment tends to be expensive and requires a doctor or other technician to interpret the results. In fluorescein staining, a chemical is administered to the patent. The patient's skin is then exposed to ultraviolet light, and perfused sections of the skin will exhibit fluorescence from the staining. The administration of the chemical, however, is undesirable. Moreover, the chemical has a limited half-life in the body. This limits this technique to one-time detection.
The most commonly used of the techniques is pH monitoring. When tissue is not adequately perfused, and it becomes ischemic, the acidity increases due to the accumulation of metabolic products. Therefore, by measuring the pH, predictions can be made as to how well the tissue is perfused. Unfortunately, pH can only be detected with at least one active electrode implanted in the tissue, which is invasive and suffers from long term measurement instability.
Attempts have been made to use impedance spectroscopy to detect stress imposed on the tissue by interruptions in perfusion or hyperthermia, for example. The work in this area has been directed to extracting information that will be characteristic of the changes induced in the tissue by the stress. One useful mechanism has been the Cole-Cole dispersion plot of tissue reactance as a function of resistance for various frequencies. The work in this area has been successful in monitoring changes in the tissue's electrical properties using the spectroscopy techniques.
The problem with these known impedance spectroscopy techniques, however, is their general inability to detect ischemia on an absolute basis. Much of the work deals with situations in which the blood supply to the tissue is occluded or the tissue is exposed to heat. The techniques monitor the effects of these stresses on the tissue over time. While interesting from a research standpoint, these techniques have little clinical value. What is needed is the ability to measure the level of ischemia even when a precise knowledge of the tissue's initial condition is unknown.
SUMMARY OF THE INVENTION
The present invention is directed to a tissue status monitoring and measurement system that is based on the principles of impedance spectroscopy. Consequently, the approach is non- or minimally-invasive, harmless to the patient, appropriate for long term monitoring, provides single quantitative results, and the necessary instrumentation is simple to use for medical personnel and relatively inexpensive.
In general, according to one aspect, the invention features a method for the detection of tissue ischemia. The method comprises applying electrical energy to the tissue that is to be analyzed. The spectral response of the tissue to the energy is then detected. The information gained from the response is then transformed into a measure of the ischemia of the tissue.
In specific embodiments, the step of applying electrical energy comprises generating sinusoidal currents of varying frequencies in the tissue. The frequencies can range between approximately 10 Hertz(Hz) and 1 MHZ.
In other aspects of the embodiments, the transformation step includes modeling the spectral response of the tissue when normal based upon the detected spectral response. This may be accomplished by extrapolating a resistance/reactance relationship into higher frequencies based upon a resistance/reactance relationship at lower frequencies. The detected spectral response of the tissue is then compared to the modeled spectral response to determine the measure of the ischemia.
In the preferred embodiment, the transformation is completed using a pattern matching algorithm that is trained to generate the measure of ischemia. The algorithm typically necessitates the generation of parameters that are descriptors of a spectral response of the ischemia of the tissue based upon the detected spectral response--in addition to--the generation of parameters that are descriptors of the spectral response of the tissue when normal based upon the extrapolated high frequency response. The two types of parameters are then compared for patterns that are indicative of a certain level of ischemia.
In order to assist in the accuracy of the system, resistive and/or capacitive components of an electrical model of the tissue may be computed and used to preprocess the parameters prior to input into the pattern matching algorithm.
The invention, however, is not limited to only detecting ischemia as it may be used to generally detect a status of tissue. The status may, for example, include whether or not tissue contains abnormal cells or tumor cells, is hypoxic, or is damaged. In this case, the invention again includes a spectral response detection with the addition of combining parameters derived from the detected spectral response of the tissue in a pattern matching algorithm that is trained to generate a measure of the status. Here again, the disclosed normal tissue modeling techniques are helpful.
In general according to another aspect, the invention also features a system for the detection of tissue ischemia or status generally. The system uses a synthesizer to generate electrical signals. An electrical current source is responsive to the synthesizer and generates electrical currents for transmission through tissue in response to the electrical signals. Some means are then used to insert the electrical current into the tissue and sense voltages generated in the tissue in response to the electrical current. This may include electrodes, coils, other energy radiators, or other techniques that allow the spectral response detection. A controller then executes a pattern matching algorithm that is trained to generate a measure of the tissue's status in response to parameters derived from a spectral response of the tissue.
In embodiments, the system may further include an analog-to-digital converter for digitizing the sensed voltages for the controller and a synchronization circuit for coordinating the operation of the synthesizer and the analog-to-digital converter. A bandpass filter is also helpful for filtering the sensed voltages prior to digitization by the analog to digital converter.
The above and other features of the invention including various novel details of construction and combinations of parts, and other advantages, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular method and device embodying the invention are shown by way of illustration and not as a limitation of the invention. The principles and features of this invention may be employed in various and numerous embodiments without departing from the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale; emphasis has instead been placed upon illustrating the principles of the invention. Of the drawings:
FIG. 1 is a simplified representation of a skeletal muscle slab in which the cells appear as closely packed pipes;
FIG. 2 is an electrical model of a muscle cell bundle;
FIG. 3 shows an inventive impedance spectroscopy system for perfusion/ischemia level monitoring and measurement;
FIG. 4 illustrates a preferred electrode configuration for attaching the system to a patient;
FIGS. 5A and 5B are a process diagram showing the operation of the inventive system for tissue perfusion/ischemia level monitoring and measurement;
FIG. 6 is a Cole-Cole plot of the reactance as a function of resistance showing the depressed minor arch of a circle that lies below the real axis, which is characteristic of tissue impedance measurements;
FIG. 7 is a Cole-Cole plot of actual impedance measurements from tissue and an extrapolation of the data based upon the low frequency data points;
FIG. 8 is a plot of tissue resistivity as a function of frequency showing the parameters used by the system to detect perfusion/ischemia levels;
FIG. 9 is a plot of the tissue impedance phase as a function of frequency showing other parameters;
FIG. 10 is a plot of tissue reactance as a function of frequency showing still other parameters;
FIG. 11 is a plot of the tissue impedance phase as a function of frequency for the modeled data generated from the Cole-Cole plot;
FIG. 12 is a plot of the tissue impedance phase as a function of frequency for the actual data detected from the spectral response of the tissue;
FIG. 13 is a plot of tissue reactance as a function of the frequency of the actual data detected from the spectral response of the tissue;
FIG. 14 is a plot of reactance as a function of frequency for the modeled data from the Cole-Cole plot; and
FIG. 15 shows the input parameters and the output for a trained neural network pattern matching algorithm.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
1. Electrical Behavior of Tissue
By way of background, biological tissues, such as skeletal muscle, exhibit complex electrical responses. Skeletal muscle tissue is electrically anisotropic: its resistivity is lower along the longitudinal axis of the cell than across it. Moreover, it is presently accepted that tissues can be described with a so-called bi-domain model. The first domain is the extracellular space and the second domain is the intracellular space, each having different associated resistances. The two domains are separated by the cell membrane that provides a capacitive effect.
FIG. 1 shows a simplified representation of a skeletal muscle slab 100 placed in a rectangular coordinant system in which the X-Y plane is parallel to the skin. The skeletal muscle cells 110 appear as closely packed pipes, each individual cylinder or pipe representing a single skeletal muscle cell. l is the length, h is the height, and b is the width of the muscle slab 100. The angle (a) is the angle between an electrode assembly axis and the longitudinal axis (x) of the muscle cells 110.
FIG. 2 shows an electrical model 200 of a muscle cell bundle. Each rectangular region 210 represents a muscle cell with L being the cell length, W 1 and W 2 are the weighting factors of the intra- and extra-cellular space, respectively, ρ i and ρ e (RHO) are the resistivities of the intra-and extra-cellular spaces. C m and σ m are the capacitance and conductivity of the cell membrane. A 1 and A 2 are the surface areas of the base and lateral surfaces, respectively, of the cell cylinder.
2. Impedance Spectroscopy System Hardware
FIG. 3 shows an impedance spectroscopy system 300 that has been constructed according to the principles of the present invention. Generally, an intelligent controller 310, such as a personal computer or microcontroller, interfaces with the environment via an interface module 312. The module 312 connects to a digital frequency synthesizer 314 that produces a sine wave voltage signal of a frequency and amplitude selected by the controller 310 via the interface module 312. A constant current source 316 controls an amplitude of the sinusoid current generated by the synthesizer for injection into the tissues 100 via source electrodes 318.
FIG. 4 illustrates the preferred electrode configuration. Two outer source surface-spot electrodes 318 connect the constant current source 316 to the tissue 100, e.g., muscle slab. The inner detection electrodes 320 in one implementation are then used to monitor the resulting voltage at the tissue 100. For some applications, however, more accurate results may be obtained from needle-type electrodes, especially where the targeted tissue is located below more superficial muscle layers, dermal layers, and fat.
Non-contact solutions may be desired for other embodiments. The electrical current can be generated in the tissue inductively. A coil is located above the tissue and the desired electrical current induced by generated magnetic fields. Measurements are made by determining the tissue impedance that is coupled into the coil. Generally, any technique that will enable the generation of the required electrical fields within the tissue is acceptable.
Returning to FIG. 3, a multiplexer 322 is connected to the detection electrodes 320. This component is required to select the input to the measurement portion of the circuit. It provides selection among the available tissue voltage electrode sets if multiple sets are available, current measurement resistors, and system calibration resistors.
An amplifier/filter 324 receives the selected output from the multiplexer 322. It has a software controlled variable gain with filtering capabilities. Specifically, band-pass filtering is performed for anti-aliasing and noise reduction. The cut-off frequencies of the filter are also software selectable.
An analog-to-digital converter 326 provides the digitized data to the controller 310. Synchronization circuitry 328 is required to find accurate instances for in-phase and quadrature sampling.
3. Impedance Spectroscopy Ischemia Determination
FIGS. 5A and 5B are process diagrams illustrating the data acquisition, signal processing, and transform performed by the hardware system, and principally the controller 310, to estimate the physiological characteristics or status of the tissues 100 based upon its spectral response.
In step 505, the spectroscopy system 100 makes measurements of the resistance, reactance, and phase at multiple, such as 20-30, frequencies in the range of 10 Hz -1 MHZ. At each selected frequency, the digital frequency synthesizer 314 generates the sinusoid at the desired frequency and the constant current source 316 drives the current through the tissue sample 100 via the electrodes 318. Simultaneously, the analog-to-digital converter 326 samples the generated voltage via electrodes 320. Knowing the frequency, amplitude, and phase of the injected current, the impedance magnitude, and phase of the tissue are measured, and the resistance and reactance are calculated.
Principally, measurements are made along the longitudinal axis of the fibers, when the tissue 100 is a muscle slab. Measurements, however, are also preferably taken from multiple, such as four different, angular orientations of the electrodes 318, 320 relative to the tissue. Information from the different electrode orientations may be gained either by using multiple electrodes at different orientations or by moving the electrodes and remeasuring.
Prefiltering of the raw signal data is then performed in step 510. Low pass filtering by time averaging is preferably performed to remove any glitches that appear in the data. Additionally, it may be necessary to sometimes perform empirical filtering to improve signal quality. In this filtering step, signal patterns, appearing in the frequency domain, that can not be caused by physiological sources are removed. Such filtering may be necessitated by gain mismatching in the spectroscopy system 100 between the different stages for different frequencies.
In step 515, the acquired impedance data is converted into resistance and reactance space to generate a complex impedance locus in the Cole-Cole dispersion representation to find the tissue's physiological characteristics at the point in time. FIG. 6 illustrates an example of this representation. Data from a given acquisition from the subject tissue is plotted as the reactance (-X S ) as a function of the real component of the impedance (Z) or the resistance (R S ) for the various measured frequencies.
Our research has established that the interpretation of information contained in the Cole-Cole plot and its extrapolation can be used as a predictor or detector of an abnormal status of the tissue. Preferably, they are used to detect ischemia, but are also applicable to detecting tumor cells, hypoxia, damage, or swelling. Each cell, if it could be measured, would have its own frequency locus characteristics. The locus that is generated through impedance spectroscopy represents the net or average locus of the cells contributing to the detected tissue response.
Changes in the tissue's status can manifest in changes in the frequency locus plot. Generally, the right side of the locus semicircle, i.e., the portion to the right of ω peak, ω=2πf, tends to be less directly useful in measuring ischemia on an absolute basis. It tends to be very sensitive to the particular type of muscle and the orientation of the electrodes relative to the muscle. As a result, it is generally a poor measure of tissue abnormal states.
The lower frequency reactance and resistance measurements, however, are useful in determining the frequency locus plot for the healthy or normal cell within the population of cells in the monitored tissue. The healthy cell will have a locus plot that is a smooth semicircle extending from R 0 to R.sub.∞. Ischemia, for example, tends to manifest itself in the frequency locus plot in the deviation between the ideal semicircle for the healthy cell and the divergence with increasing ω. This is represented in FIG. 6 by the difference between the ideal semicircle on which M is located and the deviation found in ischemic cells illustrated by the curve on which M' is located. This deviation between the M (ideal or normal cell curve) and M' curve represents changes in detected tissue reactance that are consequences of the breakdown of cellular membranes. With the onset of ischemia, the cell membrane's function is altered. This is enhanced by the increase in soluble metabolic byproducts that are not removed by circulating blood. Similar functional changes are present in tumor cells, hypoxic tissues, and tissues subject to swelling.
The objective of the signal processing is to use the frequency locus representation of the tissue's response to generate a second set of data points in addition to the actual detected spectral response. The first set of data points represents the reactance and resistance measured or detected from the tissue. This is the actual or real data. The second set of data is a modeled set of data that is used as a predictor of what the response of the tissue would be if it were healthy, non-ischemic, or otherwise normal. This modeled data is generated by extrapolating the semicircle using least square fit approximation based upon the data points of low angular frequencies omega (ω) and extrapolating these data into a continuous curve extending in the direction of the increasing omega (ω), or in the direction of R.sub.∞. Specifically, data points for low frequencies up to the second data point beyond omega (ω) peak are used to extrapolate the curve into the higher frequencies.
FIG. 7 is a frequency locus plot of actual measured data taken from an ischemic muscle slab. The dotted line 710 and the data points (♦) represent actual measured reactance versus resistance values. The data points at the lower angular frequencies (ω) are used to create the modeled data by extrapolating the semicircle into the higher frequencies. This is represented by the solid line 712. It is the divergence between the modeled data 712 and the actual data 710 that is a predictor of ischemia. Ischemia is evidenced by the elevated magnitude of the reactance at higher omega (ω) or frequency data points.
Returning to FIG. 6, the modeled data based upon the best fit circle least square approximation, which is generated based upon the low omega (ω) data points, is used to calculate R 0 , R.sub.∞ (which is highly correlated to the resistivity of the tissue since as ω approaches ∞, the contribution of the reactance to the impedance approaches 0), α, and τ=1/ω peak. Based upon known biochemical characteristics of living tissues, for example, electrolytic conductivity of human skeletal muscle is RHO∞=1.1 Ω-m, all measured and modeled resistances and reactances are normalized to specific resistances and specific reactances.
In step 520, a series of parameters are extracted from the actual or real data points and the modeled data. Most will be later directly used by a pattern matching algorithm. In more detail, for a set of measurements or time interval each of the actual data points and the modeled data points are plotted as resistivity (Ohm-m) as a function of frequency (Hz), phase (°) as a function of frequency, and specific reactance (Ohm-m) as a function of frequency. Idealized examples of these data plots are shown in FIG. 8, 9, and 10, respectively. Then, the following signal parameters are calculated based on the original or actual data and the modeled data. (In the following table "NN input" represents the corresponding parameter 1-20 that is entered into the neural network algorithm at the input and biased layers as shown in FIG. 15.)
______________________________________DEFINITION OF PARAMETERSAbbreviation Description NN input Measurement______________________________________.linevert split.Z(ω).linevert split. Frequency Directly measured data - dependence of the impedance magnitude impedance magnitudePHASE(ω) Frequency Directly measured data - dependence of the impedance phase phase of the impedanceRHO∞ High frequency #3 Assume a value, based on resistivity plateau specific tissue biochemical properties (e.g. 1.1 Ω-m)ALPHA α Angle between #4 Electrical behavior of ideal the complex tissue can be mathematical- impedance locus ly modeled with: Z.sub.M (ω) = center and low R.sub.∞ + (R.sub.0 - R.sub.∞)/ frequency real (1 + (jωτ).sup.α), where Z.sub.M is axis intercept. the modeled complex See FIG. 8. impedance, ω = 2πf is the measurement angular frequency (f is the frequency in Hz). Coefficients α, R.sub.∞, R.sub.0 and τ = 1/.sub.-- ω.sub.peak, are defined in FIG. 8. Also, Z(ω) = .linevert split.Z(ω).linev ert split. (cos φ(ω) + j sin φ(ω)) = Re{Z(ω)} + j Im{Z(ω)} where φ is the impedance phase at a frequency. The coefficients are calculated numerically, based on the best fit semi-circle to the measured data in the frequency range from DC to approximately second measured point beyond ω.sub.peak angular frequency (see FIG. 8).TAU τ = 1/.sub.-- ω.sub.peak, #5 It is calculated numerically, inverse of the in the same process as angular frequency ALPHA. that produces the highest reactive component of impedanceRO Low frequency Is calculated numerically, resistance plateau in the same process as ALPHA and TAU, see FIG. 8.R∞ High frequency Is calculated numerically, resistance plateau in the same process as ALPHA and TAU, see FIG. 8.RHO0 Low frequency #2 Calculated as: resistivity plateau RHO0 = RHO∞ · R0/R∞RHO(ω) Frequency This function can be dependence of the generated with the model, resistivity RHO(ω) = (specific real Re{Z.sub.M (ω)} · RHO∞/R .sub.∞, component of the or calculated from the impedance). measured impedance and phase: RHO(ω) = Re{Z(ω)} · RHO∞/R.sub..i nfin. = .linevert split.Z(ω).linevert split. · COS(PHASE(ω)) · RHO∞/R.sub.∞IM(ω) Frequency This function is calculatedmeasured dependence of the from the measured specific reactance impedance and phase, and (specific normalized with calculated imaginary values RHO∞ and R.sub.∞ : component of the IM(ω) = Im{Z(ω)} · impedance) RHO∞/R.sub.∞ = .linevert split.Z(ω).linevert split. · SIN(PHASE(ω)) · RHO∞/R.sub.∞IM.sub.M (ω) Frequency This function is generatedmodeled dependence of the with the model, and specific reactance normalized with calculated (specific values RHO∞ and R.sub.∞ : imaginary IM.sub.M (ω) = component of the Im{Z.sub.M (ω)} · RHO∞/R .sub.∞ impedance)PHASE.sub.M (ω) Frequency This function is generatedmodeled dependence of the with a model, using the phase of the parameters calculated, impedance as described for ALPHA.REDS Maximum slope #6 Found analytically for of the resistivity RHO(ω), based on the dispersion for model parameters, RHO(ω) explained for ALPHA. Can be calculated numerically, from data generated with the model (see ALPHA), using logarithmic frequency scale.REDW Width of the #7 Found analytically for resistivity RH0(ω), based on the dispersion region model parameters, for RHO(ω) explained for ALPHA. Defined as the width between the following two resistivity values: RHO0max = RHO0 - (RHO0 - RHO∞) · 10%, and RHO0min = RHO∞ + (RHO0 - RHO∞) · 10%. Can be calculated numerically, from data generated with the model, using logarithmic frequency scale.FRECD Central frequency #8 Found analytically for for resistivity RHO(ω), based on the dispersion for model parameters, RHO(ω) explained for ALPHA. This is a frequency for REDS. Can be calculated numerically, from data generated with the model, using logarithmic frequency scale.PHMAX Maximum #9 Found analytically for impedance PHASE.sub.M (ω), based on phase angle for the model parameters, PHASE.sub.M (ω) explained for ALPHA. Can be calculated numerically, from data generated with the model, using logarithmic frequency scale.FPHMAX Frequency at #10 Found analytically for which is PHMAX PHASE.sub.M (ω), based on measured for the model parameters, PHASE.sub.M (ω) explained for ALPHA. Can be calculated numerically, from data generated with the model, using logarithmic frequency scale.PHNS Maximum #12, Found analytically for negative slope PHASE.sub.M (ω), based on of impedance the model parameters, phase for explained for ALPHA. Can PHASE.sub.M (ω) be calculated numerically, from data generated with the model, using logarithmic frequency scale.PHNSW Width of the #11 Found analytically for negative slope PHASE.sub.M (ω), based on of impedance the model parameters, phase for explained for ALPHA. PHASE.sub.M (ω) Defined as the width between the following two phase values: PHMAX · 10%, and PHMAX. Can be calculated numerically, from data generated with the model, using logarithmic frequency scale.PHPS Average positive #13 Calculated numerically for slope of PHASE(ω), for frequencies impedance phase above FPHMAX on non- for PHASE(ω) filtered measurement data.PHPSW Width of the Calculated numerically for positive slope PHASE(ω), for frequencies of impedance above FPHMAX on non- phase for filtered measurement data. PHASE(ω) Defined as the width between the following two phase values: PHMAX, and PHMAX · 30%.PHSR Ratio of PHPS #14 Calculated, using already and PHNS calculated parameters: PHSR = PHPS/PHNSIMMAX Maximum value #15 Found analytically for of absolute IM.sub.M (ω), based specific reactance on the model parameters, for IM.sub.M (ω) explained for ALPHA. Can be calculated numerically, from data generated with the model, using logarithmic frequency scale.FIMMAX Frequency at #16) Found analytically for which IMMAX IM.sub.M (ω), based on the is measured model parameters, for IM.sub.M (ω) explained for ALPHA. Can be calculated numerically, from data generated with the model, using logarithmic frequency scale.IMNS Maximum #18) Found analytically for negative slope IM.sub.M (ω), based on the of specific model parameters, reactance for explained for ALPHA. Can IM.sub.M (ω) be calculated numerically, from data generated with the model, using logarithmic frequency scale.IMNSW Width of the #19 Found analytically for negative slope IM.sub.M (ω), based on the of specific model parameters, reactance explained for ALPHA. dispersion region Defined as the width for IM.sub.M (ω) between the following two phase values: IMMAX · 10%, and IMMAX. Can be calculated numerically, from data generated with the model, using logarithmic frequency scale.IMPS Average positive #17 Calculated numerically for slope of specific IM(ω), for frequencies reactance above FIMMAX on non- dispersion region filtered measurement data. for IM(ω)IMPSW Width of the Calculated numerically for positive slope IM(ω), for frequencies of specific above FIMMAX on non- reactance filtered measurement data. dispersion region Defined as the width for IM(ω) between the following two phase values: IMMAX, and IMMAX · 30%.IMSR Ratio of IMPS #20 Calculated, using already and IMNS calculated parameters: IMSR = IMPS/IMNS______________________________________
Based upon the modeled and actual data, a number of different plots may be generated. FIG. 11, for example, shows the impedance phase as a function of frequency for the modeled data for a test subject at 0 hours through 4 hours after initiated ischemia. FIG. 12 is a plot of the impedance phase as a function of frequency for the actual data. FIG. 13 is the reactance as a function of frequency for the actual data. And finally, FIG. 14 is reactance as a function of frequency for the modeled data. From these plots, the set of parameters in the table is calculated for each of the modeled and actual data and then for each of the times at which data is captured.
Based on the low frequency amplitude plateaus RHO0, measured at the four electrode orientations, the longitudinal and transversal axes of the skeletal muscle being investigated are determined in step 525 relative to the electrodes. This is done using a pattern recognition scheme executed by the controller 310 aided by a numerical mathematical model that predicts the electric field and current distributions in an anisotropic (and inhomogeneous) medium of a known geometrical configuration, i.e., the electrode positions on the muscle. If the orientations of the electrodes are suboptimal as determined in step 530, the operator is instructed to rotate them to a position which provides for results of higher fidelity, see step 535. Operation then returns to the measuring impedance magnitude and phase in step 505.
If the electrodes are correctly placed, the series of parameters for both the original actual data and the modeled data may then be normalized based upon back-projection techniques for the resistive and capacitive components of the tissue being monitored in step 540. Specifically, back-projection techniques are used to calculate the capacitive and resistive components for the electrical model of the muscle, for example, illustrated in FIGS. 1 and 2. This is used to help normalize and preprocess the parameters calculated in step 520 prior to their insertion into the neural network algorithm.
In more detail, the system is based on the use of surface-spot (or needle) electrodes or coils, which generate an inhomogeneous electric current distribution in the tissue. Therefore, the measured resistance is a weighted line integral of the resistivities of individual resistive components. The weights and the values of the resistive components are calculated using an iterative-back-projection scheme in step 540 once an acceptable electrode orientation has been found. Four back-projections in step 540a (for four electrode orientations) are used to supply data to the previously mentioned model of the current distribution in the anisotropic tissue in step 540b. Due to its complexity, the numerical model can not be inverted. Therefore, it must be used as a direct model (based on the electrical and geometrical parameters to find the current distribution and resistance), and iterated, in order to find the best fit set of resistivities for tissue compartments, and their weights, according to the model in FIG. 2 that produce the measured values in step 540c.
Once the resistive weights and coefficients are determined, the same approach is used to estimate the capacitive weights and values in step 545. The difference is that these values are determined mostly using the phase and reactance related parameters such as the maximum phase angles, frequency of maximum angle, width of the phase angle dispersion, and slopes of the phase angle dispersion, and the descriptors of the resistivity behavior in the dispersion region such as the dispersion slopes, central dispersion frequency, and width of the dispersion region. Specifically, in step 545a four back-projections are again used to estimate the capacitive components. Then the estimated values are used to calculate total capacitances at the angles and frequencies in step 545b. The measured values and calculated values are compared in step 545c and iterated.
Data gained by the weights and values for the resistive and capacitive components based upon the back-projections is used to preprocess the parameters calculated in 520. This can be used to de-emphasize the contribution of any intervening layers of other muscle or fat. It can also be used to desensitize the system to any offset in electrode orientation relative to the underlying tissue. Specifically, by knowing the coefficients for cellular compartments, chemical structure of compartmental cellular fluids, occupancy ratios of the compartments, and cell membrane functionality, the tissue's physiological status can be described. This increases the accuracy of the system for ischemia measurements by adjustment of the parameters in step 550.
Finally, in step 555, the parameters are used as inputs for an artificial neural network algorithm. This neural network algorithm is previously trained when the system 300 is initially configured. It is trained to correlate the differences in the parameters to any one of a number of various characteristics. For example, the pattern matching scheme of the algorithm can use the parameters to generate an estimation of various tissue physiological characteristics such as: pH, absolute ischemia level, hypoxia level, tissue damage, tissue swelling, or cancer.
FIG. 15 shows one implementation of the three layered trained algorithm. It is realized as a one bias and nineteen input parameters. The weights given to each of these parameters are indicated by the size of the corresponding boxes (2-20). These parameters are used to calculate variables 21-26 at a hidden layer. The weights given to each of these hidden variables 21-26 is again indicated by the size of the associated boxes. The output layer 27 is then calculated from the hidden layer variables.
Those skilled in the art will recognize that different combinations of input parameters may be used. In order to assist in the convergence of the neural network, it is helpful to pick variables or parameters that are very predictive of the cell's abnormal state to be detected and of the normal level for the cell. As a result, it may be useful to combine parameters with each other in order to obtain better predictors for more accurate conversions. Similarly, those parameters which tend to not contribute to the output, represented by a small box for the input variables 2-20 at the input level, may be removed from the calculations.
Further, in other implementations, it may be helpful to increase the accuracy of the system by first running a test on a muscle that is known to be normal, i.e., not ischemic, for the particular patient. Data from this test run can be used to bias or preprocess the parameters prior to their input into the neural network.
The achieved result is "instantaneous"--it requires just a few sets of measurements, that can be performed in a short interval of time (less than a minute). The analysis does not require monitoring (numerous sets of measurements, performed in a long time period) to establish the reference base-line. It provides quantitative results.
Simple ischemia monitoring can be achieved by using a smaller number of measurement frequencies or with a single angular orientation of the electrodes.
When the above described system and method are applied to the detection of normal and pathological states, such as tumor cells, of tissue, the Cole-Cole plot in this application is again used to generate extrapolated data that is characteristic of the normal cells within the cell population for which the spectral response is obtained. This information, along with the actual spectral response, is used to generate the parameters for the pattern recognition algorithm. Of course, the algorithm must be properly trained for the desired search pattern for the abnormal tissue.
While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. | An impedance spectroscopy tissue status monitoring and measurement system is disclosed. The system uses a synthesizer to generates electrical signals of selected frequencies. An electrical current source is responsive to the synthesizer and generates electrical currents for transmission through tissue. Electrodes or inductive coils of the system apply the electrical current to the tissue and sense voltages generated in the tissue in response to the electrical current. A controller determines the spectral response of the tissue by detecting magnitude and phase information of the electrical energy transmitted through the tissue. The information is then used to determine volumes of compartments within the tissue and ionic concentrations of compartmental fluids. Capacitive effects derived from the phase information are used to determine cell membrane functionality within the tissue. From this analysis, status, specifically, ischemia, may be determined on an absolute basis. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of U.S. provisional patent application Ser. No. 61/173,749, entitled ELECTRONIC SYSTEM AND METHOD FOR A GAME OF BINGO and filed on Apr. 29, 2009, the entire disclosure of which is incorporated by reference for all purposes as if set forth verbatim herein.
FIELD OF THE INVENTION
[0002] The present invention relates generally to games of chance, and, more particularly, to an electronic system and method for a game of bingo.
BACKGROUND OF THE INVENTION
[0003] Bingo is a game of chance generally played on a card resembling a 5×5 matrix. FIG. 1 illustrates a typical bingo card 100 comprising a table 102 having five columns ( 104 , 106 , 108 , 110 , and 112 ) and five rows ( 114 , 116 , 118 , 120 , and 122 ). The word “BINGO” (denoted at 124 ) is set forth above table 102 such that each letter in the word corresponds to a respective column. For instance, the letter “B” corresponds to the first column 104 . A unique number (but commonly denoted at 126 ) occupies each cell of the table.
[0004] Bingo cards, such as card 100 , may be generated randomly. That is, the numbers occupying each cell may be randomly selected from a predetermined range of numbers. For instance, a number to be located in a cell in column 104 may be randomly selected from a predetermined range of numbers, such as the range of 1 to 15. Once a number has been selected and written into the corresponding cell, it is removed from the available numbers in the predetermined range. Another number is then randomly selected from the remaining numbers in the predetermined range and written into the next available cell in column 104 . This process is repeated until unique numbers within the range have been written in all the cells within column 104 and then repeated for each of the remaining four columns: 106 , 108 , 110 , and 112 . Typically, the predetermined range for the numbers to be written in the cells of column 106 are 16 to 30; and for column 108 , 31 to 45; column 110 , 46 to 60; and column 112 , 61 to 75. Those of ordinary skill in the art will appreciate that, in such a configuration, each selected number will only appear in a specific column. That is, the number “50” will only appear in a cell located in column 110 but may appear in any of the cells in column 110 . It should be understood that other configurations may be used for creating bingo cards, such as randomly selecting numbers from a predetermined range of 1 to 75 for all five columns instead of limiting each column to a range of numbers. Random generation of bingo cards may be accomplished by hand or by using computer automation. For instance, electronic versions of the game of bingo randomly generate electronic bingo cards, such as an electronic version of bingo card 100 .
[0005] The game of bingo is played by randomly selecting a number from the overall pool of numbers (1 through 75 for purposes of the present example) and presenting the number to the players in a sequential fashion. It should be understood that the range of numbers associated with each column of the bingo card may be varied as long as the pool of numbers includes only (and all of) the numbers within the associated ranges. The players mark or “dob” their respective boards with a marker or other indicator if the number appears on the player's board. The selection and presentation of each number is generally accomplished by a moderator or may be automated and performed electronically via a display.
[0006] Prior to initiation of each game, the moderator or system establishes certain game-winning patterns, which are configurations of a card's cells that must be marked or dobbed for a player to win the game. Examples of game-winning patterns include dobbing all five cells of a row or of a column or dobbing an “X” which includes marking the card's cells from the top left corner to the bottom right corner and the cells from the top right corner to the bottom left corner. Other less complex game-winning patterns may include merely dobbing the center cell of the card. One or more game-winning patterns may be established for each game.
[0007] When the dobs on a player's board matches a game-winning pattern, the player wins and the game is completed. Typically, the winning player is awarded a prize based on the game-winning pattern dobbed on the player's board. For instance, the prize's value may be directly proportional to the complexity of the game-winning pattern and/or the odds or likelihood of obtaining the game-winning pattern. That is, it is less likely that a player will dob his board in the “X” pattern described above than merely dobbing the card's center cell. Therefore, the prize awarded to the player should the player dob the game-winning “X” pattern is much greater than that awarded for dobbing the center cell.
[0008] As noted above, bingo is defined as a game of chance. A player may be awarded a prize upon dobbing a game-winning pattern that may include money or have a substantial monetary value. For the foregoing reasons, the administering of bingo games is often governed by statutes and regulations specific to the jurisdiction in which the game is to be conducted to which the rules of the game must adhere.
SUMMARY OF THE INVENTION
[0009] The present invention recognizes and addresses the foregoing considerations, and others, of prior art construction and methods.
[0010] In this regard, one aspect of the present invention provides a system for conducting a game of chance played by users. The system comprises a server and at least two game terminals operatively connected to the server. Each terminal comprises a display, an input device, and a payment terminal configured to receive payment from one of the users. The server is configured to determine that the at least two game terminals are operatively connected to the server, establish at least one game winning pattern for the game, determine that a fee for the game has been paid by a user of each game terminal, generate at least one game board for each game terminal, allow the game to proceed only after the server has determined that each user has accepted the at least one game board presented via the respective user's game terminal and has determined that at least one user will win the game, and instruct one of the game terminals to award a prize to a winner of the game.
[0011] Another aspect of the present invention provides a method for providing a game of chance to multiple users. The method comprises the steps of receiving a fee from each user, presenting a game board to each user, determining that at least two users are playing the game, determining that the game board of one of the at least two users will present a winning pattern, and awarding a prize to a winner of the game.
[0012] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate one or more embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] A full and enabling disclosure of the present invention, including the best mode thereof directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended drawings, in which:
[0014] FIG. 1 is a schematic representation of a bingo game board;
[0015] FIG. 2 is a schematic representation of a system for conducting a game of bingo in accordance with an embodiment of the present invention;
[0016] FIG. 3 is a perspective view of a game terminal of the system of FIG. 2 ;
[0017] FIGS. 4 and 5 are schematic representations of systems for conducting a game of bingo in accordance with various embodiments of the present invention; and
[0018] FIGS. 6 and 7 are flowcharts representing processes for conducting a game of bingo in accordance with various embodiments of the present invention.
[0019] Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0020] Reference will now be made in detail to presently preferred embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present invention without departing from the scope or spirit thereof. For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
[0021] FIG. 2 illustrates a system 200 for conducting a game of chance comprising at least two game terminals 202 and 204 connected via respective connections 206 and 208 to a server 210 . Additional game terminals, such as game terminals 212 and 214 , may also be connected to server 210 via respective connections 216 and 218 .
[0022] Server 210 comprises a processor 220 and a memory 222 . Processor 220 may be a printed circuit board, processor, microprocessor, controller, or microcontroller. Memory 222 may be any memory or computer-readable medium as long as it is capable of being accessed by processor 220 , including random access memory (“RAM”), read-only memory (“ROM”), erasable programmable ROM (“EPROM”) or electrically EPROM (“EEPROM”), CD-ROM, DVD, or other optical disk storage, solid state drive (“SSD”), magnetic disk storage, including floppy or hard drives, any type of non-volatile memories, such as secure digital (“SD”), flash memory, memory stick, or any other medium that may be used to carry or store computer program code in the form of computer-executable programs, instructions, or data. Additionally, when information is transferred or provided over a network or connection, such as connection 206 , the receiving processor, such as processor 220 , recognizes the connection as computer-readable medium. Such a connection should therefore be included in the definition of memory 222 .
[0023] Memory 222 comprises computer-executable program code or instructions that when executed by processor 220 perform one or more steps of the processes described in more detail below. Memory 222 may also comprise data and one or more data structures or databases for storing information. The computer-executable program code or instructions, as should be known to those skilled in the art, usually includes an operating system, one or more application programs, other program modules, and program data.
[0024] Game terminals 202 , 204 , 212 , and 214 are identical in both construction and operation. Therefore, the following description is in reference to game terminal 202 , although it should be understood to those of ordinary skill in the art that the ensuing discussion is applicable to terminals 204 , 212 , and 214 as well. Referring to FIGS. 2 and 3 , game terminal 202 comprises a display 224 and an input 226 . Input 226 may be any device that allows a user of the respective game terminal to provide instructions to the terminal, such as a keyboard, a portion of a keyboard, a numeric pad, a touchpad, a touch matrix, a set of soft keys, a mouse, or a trackball. In a preferred embodiment, the functions of input 226 and display 224 are combined, and the components are replaced with a touch screen. Accordingly, “touch screen” is used interchangeably for input 226 and display 224 for each game terminal in the following description. Each game terminal comprises a payment terminal 228 that allows the terminal to receive payment information. Payment terminal 228 may include a card reader to read payment and account information from debit and credit cards. Payment terminal 228 may also comprise a cash acceptor for receiving cash including dollar bills and change. Payment terminal 228 may also comprise a return area to provide a user with cash in the event the user is awarded a cash prize or has a balance after the user is finished playing. Alternatively, each terminal may comprise a cash and/or change dispenser separate from payment terminal 228 . The construction and operation of payment terminals and cash acceptors and dispensers should be understood by those of ordinary skill in the art and are therefore not described in further detail.
[0025] In the presently-described embodiment, connections 206 , 208 , 216 , and 218 directly connect respective game terminals 202 , 204 , 212 , and 214 to server 210 . Server 210 handles processing of the inputs received from input 226 and controls the operation of display 224 for each game terminal. Additionally, connections 206 , 208 , 216 , and 218 operatively connect payment terminal 228 of each game terminal to server 210 . In this embodiment, server 210 performs the steps of the processes described below with respect to FIGS. 6 and 7 . Such a configuration should be understood by those of ordinary skill in the art and is therefore not described in more detail.
[0026] In another embodiment illustrated by FIG. 4 , system 300 comprises at least two game terminals 302 and 304 operatively connected to server 306 via a connection 308 . One or more game terminals, such as terminals 310 and 312 may also be connected to server 306 via connection 308 . In this embodiment, connection 308 may be a local area network in the scenario where multiple game terminals are interconnected or may be a direct serial connection in the scenario involving only two game terminals. Alternatively, connection 308 may be a wide area network, such as the Internet. Additionally, connection 308 may be either a wired or a wireless connection. In the case of a wireless connection, it should be understood that connection 308 may be any wireless protocol or technology capable of interconnecting one or more terminals, such as Bluetooth, wireless fidelity (“Wi-Fi”), or a cellular data network. One will appreciate that use of wireless technologies, such as a cellular data network, or a wide area network allow game terminals 302 and 304 to be located remotely with respect to one another yet allow the users of the terminals to engage in a game of bingo as described in more detail below.
[0027] In the presently-described embodiment, game terminals 302 , 304 , 310 , and 312 each comprise a processing device 314 , a memory 316 , and a touch screen 318 , where the memory and touch screen are operatively connected to the processing device. Memory 316 includes computer-executable code, instructions, or programs that, when executed by processing device 314 , manage the operation of touch screen 318 . That is, the programs and/or modules stored on memory 316 and executed by processing device 314 control the receipt of information from touch screen 318 and the display of information to the screen. Processing device 314 transmits and receives data representative of this information to and from server 306 via connection 308 . Other than the functions described above, server 306 performs the steps of the processes described below with respect to FIGS. 6 and 7 .
[0028] Referring to FIG. 5 , in yet another embodiment, system 400 comprises at least two game terminals 402 and 404 connected via connection 406 . Additional game terminals, such as terminals 408 and 410 , may be connected to game terminals 402 and 404 via connection 406 . In this embodiment, connection 406 may be any of the connections described above, including a direct connection or a network. Game terminals 402 , 404 , 408 , and 410 each comprise a processing device 412 , a memory 414 , and a touch screen 416 . Game terminals 402 , 404 , 408 , and 410 , and the components thereof, function in a manner similar to that described above with respect to FIG. 4 . That is, processing device 412 controls the operation of touch screen 416 for each terminal. In this embodiment, however, one of the game terminals is selected to perform the processes described below with respect to FIGS. 6 and 7 . It should be understood by those of ordinary skill in the art that the game terminal selected to perform those processes may be decided based on a number of factors, such as which game terminal is first accessed by a user.
[0029] FIG. 6 illustrates the processes for conducting a game of bingo in accordance with an embodiment of the present invention. For explanation purposes, the following description of the processes is made with respect to system 200 illustrated in FIG. 2 and game terminal 202 illustrated in FIG. 3 although it should be understood that the processes described herein are applicable to each of the embodiments set forth above with respect to FIGS. 2 , 4 , and 5 . For instance, in the embodiment described below, processor 220 of server 210 performs the methods set forth in the following description upon execution of computer-readable code or instructions stored on memory 222 . In another embodiment, however, one or more processors 412 of one or more game terminals 402 , 404 , 408 , and 410 performs all or a portion of the methods described below upon execution of computer-readable code or instructions stored on respective memories 414 .
[0030] Referring to FIGS. 2 , 3 , and 6 , system 200 is initialized at step 500 to ensure at least two game terminals, such as terminals 202 and 204 , are operational and that the connections between the game terminals and server 210 , such as respective connections 206 and 208 , have been established. System 200 also initializes certain variables and other options that may be set by a system administrator, such as the patterns that will be available to the players as game-winning patterns. Likewise, the award or prize corresponding to each game-winning pattern is also defined at this step. At step 502 , a user (hereinafter “Player 1 ” for simplicity) accesses game terminal 202 . This usually requires Player 1 to provide system 200 with a fee or bet, which is accomplished via payment terminal 228 . The fee or bet is set by system 200 and is initialized at step 500 . Those of ordinary skill in the art should appreciate that the entry fee or bet may be set to any desired predetermined amount. In a preferred embodiment, the entry fee is initialized to ten cents ($0.10). Data representative of money or credit provided by Player 1 to game terminal 202 is transmitted by payment terminal 228 of the terminal to server 210 via connection 206 . Server 210 controls operation of payment terminal 228 in order to handle the money or credit provided by (or to) Player 1 . As illustrated in FIG. 3 , the touch screen of game terminal 202 displays other information relevant to Player 1 , such as the player's running balance including any prize money awarded to the player as described below. Once the entry fee is accepted, the process continues to step 504 .
[0031] At step 504 , processor 220 of server 210 randomly generates an electronic bingo card similar to the manner described above with respect to FIG. 1 based on instructions stored on memory 222 . The touch screen of game terminal 202 presents the bingo card to Player 1 , who may either select the card or request another card at step 506 using the touch screen. Should Player 1 request another card, process flow returns to step 504 , where processor 220 generates another card. Should Player 1 select the bingo card presented by game terminal 202 , process flow proceeds to step 508 . This may be accomplished by Player 1 selecting a portion of the touch screen labeled “Play Game” or by Player 1 placing a bet as described below with respect to FIG. 7 by selecting a portion of the touch screen labeled “Place Bet.” Process flow pauses at step 508 until server 210 confirms another user (“Player 2 ”) has progressed to step 508 as described below.
[0032] Player 2 accesses game terminal 204 at step 510 by providing an entry fee similar to that described above with respect to Player 1 . At step 512 , system 200 (that is, processor 220 ) randomly generates an electronic bingo card, which server 210 presents to Player 2 via the touch screen of game terminal 204 . Player 2 has the option of selecting the card or requesting another card at step 516 similar to the manner described above with respect to Player 1 . Once Player 2 has selected a card, process flow proceeds to step 508 .
[0033] As noted above with respect to FIG. 1 , numbers 1 through 75 are typically available as a number pool in a game of bingo. At step 518 , processor 220 randomly selects 30 numbers from the number pool. In the presently-described embodiment, processor 220 checks at step 520 the randomly selected 30 numbers against the randomly generated bingo cards to ensure that at least one of the cards, in combination with the random selection of numbers, will provide a game-winning pattern as identified by the system at step 500 . If the random selection of the 30 numbers will not cause any of the bingo cards to present a game-winning pattern, process flow returns to step 518 , where system 200 randomly selects another 30 numbers from the number pool. The process flow continues in this manner until processor 220 confirms that at least one of the bingo cards will produce a game-winning pattern based on the 30 randomly selected numbers and then continues to step 522 . In a preferred embodiment, processor 220 checks, at step 520 , the randomly selected numbers against the randomly generated electronic bingo cards to ensure the number located in the middle cell for at least one of the cards matches one of the numbers.
[0034] It should be understood by those of ordinary skill in the art that any game-winning pattern may be used to ensure that at least one of the players' bingo cards will result in a game-winning pattern based on the 30 numbers. It should be further understood that the process described above with respect to step 520 in each embodiment ensures that at least one of the bingo cards will result in a game-winning pattern. Those of ordinary skill in the art will appreciate that the above process does not predetermine which player will exhibit a game-winning pattern first, nor does it predetermine all of the game-winning patterns that will occur. That is, although system 200 confirms that one player's card will exhibit a game-winning pattern, another player's card may exhibit a game-winning pattern first (which may be a pattern that system 200 does not attempt to confirm exists with respect to the cards).
[0035] At step 522 , processor 220 informs the players that the game is beginning via the respective touch screen of the player's game terminal. At step 524 , the touch screens display one of the 30 numbers as a graphic of a bingo ball bearing the number on the front surface of the ball to the players via the touch screen of each respective game terminal. If a player's electronic bingo card includes the number displayed, the player dobs the card using the touch screen. Alternatively, processor 220 automatically dobs the player's electronic bingo card. Process flow proceeds to step 526 , where processor 220 determines whether the dobs on the electronic bingo card of any player matches the game-winning patterns. If not, process flow returns to step 524 and proceeds as described above. If the dobs on any of the players' electronic bingo cards match a game-winning pattern, process flow proceeds to step 528 where any player with a game-winning pattern is awarded a prize. That is, the award or prize corresponding to a specific game-winning pattern is deposited into the respective player's running balance if the player has an electronic bingo card, the dobs of which match the game-winning pattern. As noted above, the prize is directly proportional to the odds of matching the game-winning pattern. The player's balance as shown on the touch screen of the player's game terminal reflects the addition of the prize. In the presently-described embodiment, the player is awarded the prize associated with the best game-winning pattern exhibited by the player's card even if it exhibits multiple game-winning patterns. The order of game-winning patterns is established at step 500 , but the “best” game-winning pattern is typically defined as the pattern associated with the lowest probability of occurrence. It should be understood, however, that a system administrator may define game-winning patterns and the prizes and order associated therewith as desired.
[0036] In another embodiment, system 200 displays all 30 numbers at once on each terminal's display at step 524 , rather than displaying each individual number sequentially as described above. At step 526 , processor 220 automatically dobs each player's electronic bingo card for each number on the card that matches any of the 30 numbers. Process flow proceeds directly to step 528 , where any player with a game-winning pattern is awarded the prize corresponding to the game-winning pattern. It should be understood that at least one game-winning pattern will occur due to the confirmation of such performed by system 200 at step 520 when the ball drop was selected.
[0037] At step 530 , processor 220 presents an inquiry to each player via the touch screen of the player's respective game terminal whether the player would like to participate in another game, to which the player responds by selecting predetermined indicia using the touch screen. It should be understood that once a game-winning pattern is exposed at step 526 , process flow directs all players involved in the game to step 528 including those whose cards do not exhibit a game-winning pattern. At step 528 , prizes are awarded to those players who have a card exhibiting a game-winning pattern, and process flow directs all players involved in the game to step 530 where the inquiry described above is presented to each player. If the player responds in the affirmative to the inquiry, process flow proceeds to step 532 where system 200 asks the player if the player would like to retain the current electronic bingo card. If the player responds in the affirmative, process flow returns to step 508 and proceeds in the manner described above.
[0038] If the player desires a new card, process flow returns to step 502 where the player must pay another entry fee to receive another randomly generated bingo card. Process flow then proceeds in the manner described above. Thus, it should be understood that a player must pay for each newly generated card that the player will use, but does not repay the entry fee as long as the player continues to use the same card. If the player chooses at step 530 not to play again, system 200 cashes out the player at step 534 . If the player has a positive balance, money corresponding to the balance is returned to the player via payment terminal 228 .
[0039] FIG. 7 illustrates the processes for conducting a game of bingo in accordance with another embodiment of the present invention. Referring to FIGS. 2 , 3 , and 7 , process flow proceeds to step 508 in a manner identical to that described above with respect to FIG. 6 . Process flow then proceeds to step 600 where Players 1 and 2 are asked to place their respective bets. In a preferred embodiment, each player is required to bet a minimum amount, such as thirty cents ($0.30). Players may increase their respective bets using the terminal's touch screen. For instance, the touch screen presents selectable indicia on the screen with the text “Increase Bet” and “Max Bet.” Pressing the area corresponding to the “Increase Bet” increases the player's bet by a predetermined amount. In the presently-described embodiment, each selection of this area increases the player's bet by a multiplier that corresponds to the number of times the area was selected by the user. For instance, selecting the area three times will increase the player's bet by a multiplier of 3. In a preferred embodiment, the multiplier may be increased 10 times before resetting to a value of 1. Selecting the area of the touch screen corresponding to the “Max Bet” immediately sets the multiplier to the maximum value, which, in this embodiment, is 10.
[0040] By way of example, Player 1 provides the entry free of ten cents ($0.10) at step 502 . At step 600 , the touch screen of game terminal 202 presents a request to Player 1 to provide the minimum bet fee of thirty cents ($0.30). Player 1 may decide to increase the bet by a multiplier of 4 and selects the appropriate area of the touch screen of terminal 202 four times. As a result, the bet is increased from thirty cents ($0.30) to one dollar and twenty cents ($1.20). Player 1 may decide to increase the bet to the maximum amount by selecting the appropriate area of the touch screen. As a result, the bet is increased to three dollars ($3.00). It should be understood by those of ordinary skill in the art that increasing the bet increases the prizes awarded for each game-winning pattern by the increase in the multiplier. Thus, increasing the multiplier 4 times also increases any prizes fourfold.
[0041] System 200 is configured to provide Player 1 with the ability to increase the minimum bet 4 times and then to select the maximum bet instead. Likewise, system 200 allows Player 1 to reset the desired bet to the minimum amount by selecting the area of the touch screen labeled “Increase Bet” a sufficient number of times. It should be understood by those of ordinary skill in the art that the entry fee, minimum bet, maximum bet, and multipliers may be defined as desired and are initialized at step 500 .
[0042] Once Players 1 and 2 have selected their respective desired bet amounts, each player selects an area of the touch screen of the player's game terminal labeled “Place Bet” at step 602 . Those of ordinary skill in the art will appreciate that the labels described above may be modified to suit the game's design. For instance, each player may select a portion of the respective touch screen labeled “Play Game,” “Spin,” etc. to indicate the player is ready to proceed. Should a player's balance fall below the minimum bet amount or below an amount needed to continue, system 200 invites the player to insert additional money using payment terminal 228 . Similarly, each player may provide additional money via payment terminal 228 at any time the player is using a game terminal. Upon receipt of the money, the terminal's touch screen reflects the increase to the player's balance. Game play proceeds to step 518 and continues in the manner described above with respect to FIG. 6 . Additionally, a player may finish playing at any time by pressing an area of the touch screen of the player's terminal labeled “Cash Out.” If the player's running balance reflects a positive amount, the balance is returned to the player via the respective terminal's cash and/or change dispenser.
[0043] In another embodiment, steps 600 and 602 precede step 508 . In this embodiment, after selecting a card, process flow proceeds from steps 506 and 516 to step 600 and then to step 602 in a manner similar to that described above. After each player selects at step 602 the portion of the respective touch screen labeled “Place Bet” or “Begin,” process flow proceeds to step 508 where system 200 pauses until the system confirms that at least two players are involved in the game. Process flow then proceeds in a manner identical to that described above with respect to FIG. 6 .
[0044] In another embodiment with reference to FIG. 7 , process flow proceeds directly to step 508 from step 528 after prizes are awarded to all players whose boards exhibit a game-winning pattern. At this point, system 200 pauses for each player to make a selection using the player's respective touch screen. For example, with reference additionally to FIG. 3 , each player may select portions of the player's touch screen corresponding to areas labeled “Cash Out,” “Place Bet” (or “Play Game”), “New Card,” “Increase Bet,” or “Max Bet.” Selecting “Cash Out” performs the functions described above with reference to step 534 . Selecting “Place Bet” places the desired bet and informs system 200 that the player is ready to proceed with the game. Alternatively, selecting “Play Game” places the current bet and indicates the player is ready to proceed. System 200 pauses at step 508 until the system confirms that at least two players are ready to proceed as described above and then continues accordingly. Selecting “New Card” returns the player to step 502 where the player must pay the fee required to select a new bingo card. Process flow then proceeds in the manner described above. Selecting “Increase Bet” or “Max Bet” performs the functions described above with respect to steps 600 and 602 . It should be understood that each player may make any of these selections at any time system 200 is idle or is awaiting a response or input from the player but not while engaging in the actual game. For instance, each player is unable to select the “Cash Out” or “New Card” areas of the player's respective touch screen during steps 524 , 526 , and 528 . It should be further understood that, in an embodiment where steps 600 and 602 precede step 508 as described above, process flow proceeds directly to step 600 from step 528 in a manner similar to that set forth above and awaits each player's selection.
[0045] In another embodiment, each touch screen displays an area labeled “Help.” Upon selection by a player of this area, the touch screen displays a “help screen” which provides instructions to the player regarding all the options currently available to the player as described above. For instance, the help screen explains to the player what selection of certain areas of the touch screen will accomplish, such as selection of the “Max Bet” label. When viewing the help screen, the player always has the option to exit the help screen and continue as described above.
[0046] In the embodiments described above, data representative of each action of any player or of system 200 is written to memory 222 by processor 220 . That is, system 200 maintains a log of all actions that take place before, during, and after a game of bingo. For instance, system 200 saves data to memory 222 representative of each player's bet for each bingo game played. This data may be stored within a data structure in memory 222 , but is preferably stored within a database in memory maintained by server 210 . Server 210 may periodically provide this data to a host system that manages multiple systems similar to system 200 . This may be accomplished by email, file transfer protocol (“ftp”), really simple syndication (“RSS”) feed(s), or any other mechanism capable of transmitting information as necessary. It should be understood that the terminal that manages the bingo game in the embodiment described above with respect to FIG. 5 stores the data in memory 414 . Similarly, the terminal provides this data to the host system. Alternatively, the host system may access server 210 or the terminals to retrieve the desired data.
[0047] In another embodiment that does not include the use of server 210 , such as system 400 described above with respect to FIG. 5 , processors 412 of the game terminals perform all or a portion of the methods described above. For instance, processor 412 of game terminal 402 performs the functions described above with respect to steps 502 , 504 , and 506 of FIG. 6 , while processor 412 of game terminal 404 performs the functions described above with respect to steps 510 , 512 , and 516 of FIG. 6 . If game terminal 404 was accessed by a user prior to a user accessing game terminal 402 , then processor 412 of terminal 404 performs the functions described above with respect to the game of bingo, such as randomly selecting the 30 numbers from the number pool, as well as logging all player and system actions, as described above. Processor 412 of game terminal 402 , however, continues to perform functions specific to the respective game terminal, such as displaying information to the user and receiving input from the user, and communicates data representative of such actions to processor 412 of game terminal 404 via connection 406 . The implementation of such a shared processing system should be understood to those of ordinary skill in the art and is therefore not described in more detail.
[0048] It should be understood from the above description that system 200 requires the participation of at least two players before commencing play. One of ordinary skill in the art understands that a variable may be initialized at step 500 setting the minimum number of players required to reach step 508 before proceeding. For example, system 200 may be configured to require the access and use of four terminals prior to proceeding beyond step 508 . Alternatively, system 200 may include all players that reach step 508 within a certain timeframe in a game as long as at least two players are present. For instance, system 200 may pause for a period of time, such as five seconds, each time a player reaches step 508 and is prepared to play. Thus, if other players reach step 508 during this time, they are added to the game in progress, and system 200 extends the waiting period another five seconds. One of ordinary skill in the art will also appreciate that a variable corresponding to the maximum number of players allowed per game, such as ten players, may be initialized at step 500 . In the embodiment described above with respect to FIG. 6 , when the number of players that reach step 508 is equal to this amount, process flow proceeds immediately to step 518 (or step 600 in the embodiment described above with respect to FIG. 7 ).
[0049] In a preferred embodiment, system 200 initiates a game each time two players reach step 508 and are prepared to play. For instance, Players 1 and 2 reach step 508 and engage in a game of bingo. Players 3 and 4 then reach step 508 and engage in another game of bingo. Upon completion of both games, Players 1 and 3 are prepared to play again, while Players 2 and 4 desire to change bingo cards. Players 1 and 3 subsequently reach step 508 and engage in a game of bingo. The next two players to reach step 508 and are prepared to play, engage in a game of bingo regardless of whether it is Player 1 , 2 , 3 , or 4 .
[0050] In the presently-described embodiment, each player's balance is represented as a cash value. That is, the player's balance as denoted on the touch screen of the player's terminal is an amount measured in dollars. It should be understood by those of ordinary skill in the art that each balance may be displayed as credits instead of cash. For instance, a balance of one dollar ($1.00) may be converted to credits, where one cent ($0.01) is equivalent to 1 credit. Thus, the player's balance would be presented as 100 credits. It should be further understood that system 200 may present the option of displaying the balance as cash or credits to each player. Specifically, each player may choose between having the player's balance presented as cash or as credits.
[0051] In an embodiment where the player's balance is displayed as credits (either automatically or by the player's choice), system 200 provides the player with an option to change the game's denom using the touch screen of the player's terminal. A denom is a quotient by which a player's credits are valued. In the presently-described embodiment, the default denom is 1 although it should be understood that the default may be altered as desired. That is, a player that has a balance of one dollar ($1.00) has 100 credits. The credits are divided by the denom, or 1, resulting in a balance of 100 credits. The player may alter the denom, thereby changing the quotient by which the credits are valued. If the player adjusts the denom to 2, the change is reflected in the player's balance, which is adjusted to 50 credits. If the player provides the terminal with another dollar ($1.00), 50 credits are added to the player's balance. The use and effect of denoms should be understood by those of ordinary skill in the art and are therefore not described in more detail.
[0052] While one or more preferred embodiments of the invention have been described above, it should be understood that any and all equivalent realizations of the present invention are included within the scope and spirit thereof. The embodiments depicted are presented by way of example only and are not intended as limitations upon the present invention. Thus, it should be understood by those of ordinary skill in this art that the present invention is not limited to these embodiments since modifications can be made. Therefore, it is contemplated that any and all such embodiments are included in the present invention as may fall within the scope and spirit thereof. | A system and method for providing a game of chance and proceeding with the game only after determining that the game involves at least two users and that at least one of the game boards of the users will present a game winning pattern and awarding a prize to a winner of the game. | 6 |
TECHNICAL FIELD
[0001] The present invention relates to a method for increasing a moisture content of a skin and skin elasticity by ions, and a facial care apparatus for increasing the moisture content of a skin and skin elasticity.
BACKGROUND ART
[0002] Conventionally, in order to increase the moisture content of a skin and improve skin elasticity, the method of coating the skin with a coating agent containing a moisturizing component has been generally carried out. Besides, Patent Literature 1 discloses the method which suppresses drying of a skin and increasing the moisture content of the skin by increasing the moisture content of the environment by spraying moisture into the air by a humidifying device. Further, Patent Literature 2 discloses the method which condenses the moisture in the air, atomizes the condensed moisture and sprays it, but this method needs to provide the function of making the temperature of the air low for condensation of the moisture and causing dew condensation and flocculation, and needs to use an expensive element such as a Peltier element. Further, there have been the problems that the power consumption increases and the device is upsized at the same time.
[0003] Further, an electric field is further applied to generated steam to change the steam to charged water droplets called “steam ions”, and the water droplets are supplied. (For example, Patent Literature 3)
[0004] Further, recently, water droplets of a nano size are made by using an ultrasonic element, an electric field is further applied to the water droplets, and the charged water droplets in the form of ultra-fine particles are made and supplied. (For example, Patent Literature 4)
[0005] Explaining the device according to FIG. 18 , water for making steam is supplied to a boiler 10 , and is warmed by a heater 9 to generate steam instantly. Subsequently, the steam is subjected to corona discharge with an ion steam generator 11 to contain ions, and is injected to a face from an ejection port 8 .
[0006] However, if the water in the tank which is supplied to generate steam, mist and the like becomes insufficient, water has to be added thereto, and much effort is required.
[0007] Further, the water in the supply water tank is left for a long time, whereby saprophytic bacteria increase, and the water may be in an unhygienic state. If Legionella pneumophila and the like have grown, a trouble is likely to occur to the users, and as a result, usability is reduced.
CITATION LIST
Patent Literature
[0008] [Patent Literature 1] Japanese Patent Laid-Open Publication No. 2009-78245
[0009] [Patent Literature 2] Japanese Patent Laid-Open Publication No. 2006-61407
[0010] [Patent Literature 3] Japanese Patent Laid-Open Publication No. 2007-75243
[0011] [Patent Literature 4] Japanese Patent Laid-Open Publication No. 2007-296284
SUMMARY OF INVENTION
Technical Problem
[0012] The present invention is invented in view of the above described conventional problems, and provides a beauty apparatus which does not need to generate steam, mist and the like.
Solution to Problem
[0013] The outline of the solution to the problem according to the present invention will be described hereinafter.
[0014] A method for increasing a moisture content in a human skin surface and improving skin elasticity of the present invention irradiates a human skin surface with positive and negative ions which are generated by an electric discharge to increase the moisture content of a skin and improve the skin elasticity.
[0015] The present method brings about the effect of increasing a skin moisture content and improving skin elasticity by the ions generated by an electric discharge and does not perform humidification using water, and therefore, the humidity in a room does not rise. Further, the moisture in the air is not condensed, and therefore, the advantages are provided, that the device cost does not significantly increase, the power consumption is small and the device is not upsized.
[0016] Further, the method for increasing a moisture content in a human skin surface and improving skin elasticity is characterized in that concentrations of the positive and negative ions are each 7000/cm 3 or more.
[0017] As a result of performing a study by changing the concentrations of the positive and negative ions, it has become obvious that the effect of increasing the skin moisture content and the effect of improving skin elasticity can be obtained by generating ions of 7000/cm 3 or more.
[0018] Further, the method for increasing a moisture content in a human skin surface and improving skin elasticity of the present invention uses H 3 O + (H 2 O)m (m=a natural number such as 0, 1, 2, 3 . . . ) as the positive ions, and O 2 − (H 2 O)n (n=a natural number such as 0, 1, 2, 3 . . . ) as the negative ions.
[0019] The mechanism of the effect of increasing the skin moisture content by both the positive and negative ions is not clear, but it is conceivable that
1) By simultaneous irradiation with H+ ions and O 2 − ions, —OH groups adhere to a skin surface, the skin surface is locally hydrophilized, and water molecules adhere and easily penetrates into the skin. 2) Water molecules surrounding the ions are taken into the skin, and the like.
[0022] The water molecules surrounding the ions are due to the water molecules which are originally present in t he air, and the amount of the water molecules which are in contact with a skin is not significantly increased. Accordingly, it is conceivable that a large skin moisture increasing effect cannot be obtained by 2), and it is obvious that 1) brings about a large effect.
[0023] From the present mechanism, it is important to contain H + and O 2 − as ions, and it is estimated that thereby, OH groups are generated, and the effect of increasing the skin moisture is brought about.
[0024] Meanwhile, skin elasticity generally depends on the composition of a deeper portion (dermis) of a skin. Improvement of the skin elasticity is considered to be the result that the moisture of the skin surface increases to thereby increase the content of the moisture kept in the dermis, and the elasticity of the skin is improved. More specifically, the skin elasticity improving effect is estimated as being obtained as the secondary action of the effect of increasing the skin moisture content by ions.
[0025] A beauty apparatus of the present invention includes a blower, and a casing in which the blower is contained, and a blowoff port for blowing air sucked by the blower to outside, and a suction port for sucking the air from outside are formed, and is characterized by further including ion generation means downstream of the blower in the casing, and in that the ion generation means generates positive ions H 3 O + (H 2 O)m (m is 0 or an optional natural number), and negative ions O 2 − (H 2 O)n (n is 0 or an optional natural number).
[0026] The beauty apparatus of the present invention includes a configuration including changing means of a downflow velocity and a downflow direction of air that is placed at a downstream side of the blower and an upstream side of the ion generation means to enhance an air blowing velocity in a vicinity of the ion generation means and to turn a blowing direction of the air from the blowoff port.
[0027] Furthermore, the beauty apparatus of the present invention includes a configuration including control means that controls an air blowing amount of the blower, and an ion generation amount of the ion generation means, in the casing, and wind velocity detection means at the blowoff port, wherein when the wind velocity detection means detects that a blowoff wind velocity at the blowoff port is a predetermined value or more, the control means controls a wind velocity of the blower to be a predetermined value or less, or including an ion detector that detects an ion concentration at the blowoff port in the casing, wherein when the ion detector detects an ion concentration of a predetermined value or less, the control means controls the ion generation means to make a generation amount of ions an ion concentration of the predetermined value or more.
[0028] The beauty apparatus of the present invention irradiates a user with the positive and negative ions which are generated by using the ion generation element by carrying the positive and negative ions by an air flow at a low speed, and increases the concentration of the ions for irradiating the skin surface to a predetermined value or more, whereby the positive and negative ions react to produce water, which can moisten the skin and can improve the elasticity of the skin. Further, the blowoff port ion detector is included so that the ion concentration becomes high when the ions which are supplied from the ion generation means are released from the blowoff port, and thereby the blowoff velocity is controlled to be kept at a low level while the ion concentration is elevated.
Advantageous Effect of Invention
[0029] The method for increasing the moisture content in a human skin surface and improving the moisture retaining function of a dermis, and the beauty apparatus according to the present invention bring about the effect of increasing the skin moisture content and the effect of improving the skin elasticity by irradiating the skin of a user with the positive and negative ions which are generated by an electric discharge, and because the method and apparatus do not perform humidification using water, the method and apparatus do not require the storage, replenishment and sanitary supervision of water, or do not increase the humidity in the room. Further, the method and the apparatus do not use water, and therefore, the beauty apparatus which can be easily used at any time can be provided. Further, the skin can be prevented from being dried by controlling the wind velocity, and the amount of water generated on the skin surface can be increased by controlling the ion concentration.
[0030] Furthermore, a water storage tank and a heating device for condensing the moisture in the air are not required, and therefore, the advantages are provided, that the entire device can be made compact, the device is easily handled and portable, the device cost does not significantly increase, the power consumption is small, and the device is not upsized.
BRIEF DESCRIPTION OF DRAWINGS
[0031] FIG. 1 is a schematic view showing the principle of an ion generation element.
[0032] FIG. 2 is a schematic view showing an ion generation apparatus and a blower fan.
[0033] FIG. 3 is a graph of change in skin moisture content according to embodiment 1.
[0034] FIG. 4 is a graph of change in skin moisture content according to embodiment 2.
[0035] FIG. 5 is a graph of change in skin moisture content according to comparative example 1.
[0036] FIG. 6 is a graph of change in skin moisture content according to comparative example 2.
[0037] FIG. 7 is a graph of change in skin moisture content according to embodiment 2.
[0038] FIG. 8A is a graph of change in skin elasticity R 5 according to embodiment 2.
[0039] FIG. 8B is a graph of change in skin elasticity R 7 according to embodiment 2.
[0040] FIG. 9 is a conceptual view showing a state of use of a facial care apparatus of the present invention.
[0041] FIG. 10 is a conceptual view of a structure of the facial care apparatus of the present invention.
[0042] FIG. 11 is a conceptual view of a wind directing body of the present invention, ( a ) is a plan view, ( b ) is a sectional view taken along the line A-A, and ( c ) is a sectional view taken along the line B-B.
[0043] FIG. 12 is a conceptual view showing the flow of ions of the present invention.
[0044] FIG. 13 is an external view of an ion generation device, ( a ) is a top view, ( b ) is a plan view and ( c ) is a right side view.
[0045] FIG. 14 is an example of a circuit of the ion generation device.
[0046] FIG. 15 is a circuit diagram of a wind velocity detector.
[0047] FIG. 16 is a control block diagram of the facial care apparatus.
[0048] FIG. 17 is a circuit diagram of an ion detector.
[0049] FIG. 18 is a structural view of a conventional facial care apparatus.
DESCRIPTION OF EMBODIMENTS
[0050] A mode for carrying out the present invention will be described in detail with reference to the drawings.
Embodiment 1
[0051] FIG. 1 is a schematic view explaining the principle of an ion generation element according to the present invention, and FIG. 2 is a conceptual view of an ion generation apparatus using the ion generation element.
[0052] An ion generation apparatus 6 houses an ion generation element 60 shown in FIG. 1 inside a case. The ion generation element 60 has voltage application needle electrodes 1 and 2 connected to high-voltage generation devices 4 and 5 , and ground electrodes 3 disposed adjacently to the aforesaid voltage application needle electrodes. In the ground electrodes 3 , the same number of through-holes 31 , which allow the voltage application needle electrodes 1 and 2 to penetrate therethrough, as the number of voltages application needle electrodes are placed. The voltage application needle electrodes 1 and 2 have needle-shaped tip ends, and are disposed so that the voltage application needle electrodes 1 and 2 are located in centers of through-holes 31 of the ground electrodes 3 with the voltage application needle electrodes 1 and 2 connected to and supported by the high-voltage generation devices 4 and 5 , and the needle-shaped tip ends are each located within the range of the thickness of the through-hole 31 . The high-voltage generation devices 4 and 5 supply DC pulse voltages to the voltage application needle electrodes 1 and 2 to cause an electric discharge to ionize the air in the vicinity of the ground electrodes 3 . Ions generated from the ion generation element 60 of the ion generation apparatus 6 are released from an opening 61 of the case. Subsequently, the released ions are diffused into the atmosphere by a blowing fan 7 which is installed adjacently to the ion generation apparatus 6 .
[0053] The principle of ion generation of the ion generation element 60 will be described.
[0054] As the ion generation electrodes of the ion generation element 60 , the voltage application needle electrode 1 (positive ion generation electrode) connected to the high-voltage generation device 4 , and the voltage application needle electrode 2 (negative ion generation electrode) connected to the high-voltage generation device 5 are included. A DC pulse voltage is supplied to the aforesaid voltage application needle electrode 1 , and a positive voltage is applied. A DC pulse voltage is supplied to the voltage application needle electrode 2 , and a negative voltage is applied. By a corona discharge, the air in the vicinity of the positive ion generation electrode 1 and the ground electrode 3 is positively ionized, and the air in the vicinity of the negative ion generation electrode 2 and the ground electrode 3 is negatively ionized.
[0055] The amount (concentration) of the ions which are generated is regulated according to the voltage/pulse period, which is applied to the voltage application needle electrodes 1 and 2 by the high-voltage generation devices 4 and 5 .
[0056] Next, experiments were conducted on change of the moisture content of a skin by air containing the positive ions and negative ions generated by the ion generation element 60 and the air which does not contain the positive ions and negative ions.
<Experiment Method>
[0057] A partition plate was placed in the center of a face which was a test object, and the face was divided into a left face and a right face. The positive and negative ions which were generated from the ion generation element were fed (irradiated) to a left cheek of the face by the fan 7 , and only the air which did not contain ions was blown (irradiated) to a right cheek. In this case, the distance between the ion generation element and the face was set at 30 cm. Further, the wind velocity at the face was set at 1 m/sec. The skin moisture content was measured with WSK-P500U (made by WaveCyber Corp. trade name).
[0058] As a result of analyzing the structures of the ions generated from the present ion generation electrodes with a TOF-mass spectrometer (time-of-flight mass spectrometer), generation of H 3 O + (H 2 O)m (m=a natural number such as 0, 1, 2, 3 . . . ) as positive ions and O 2 − (H 2 O)n (n=a natural number such as 0, 1, 2, 3 . . . ) as negative ions was able to be confirmed.
Experiment 1
[0059] The voltages applied to the positive and negative ion generation electrodes (high-voltage application needle electrodes 1 and 2 ) of the ion generation element by the high-voltage generation devices 4 and 5 and the pulse periods were regulated so that the ion concentration on the face became 7,000/cm 3 .
[0060] The result of measuring the change of the moisture content of the surface (skin) in this manner is shown in FIG. 3 . The graph shown in FIG. 3 shows the change over time of the moisture contents of the face (skin) to which the air containing positive and negative ions are applied (irradiated), and the face (skin) to which only the air containing no ions is applied (irradiated). According to the graph, the result that the face (skin) irradiated with positive and negative ions increased in moisture content of the face (skin) with irradiation time as compared with the face (skin) irradiated with only blown air was obtained.
Experiment 2
[0061] With the same method as in experiment 1, the change of the moisture content of the face (skin) was measured. However, the voltages of the high-voltage generation devices 4 and 5 which were applied to the ion generation electrodes (high-voltage application needle electrodes 1 and 2 ) and the pulse periods were regulated so that the concentration of the ions for irradiation was 25000/cm 3 . The result of measuring the change of the moisture content of the face (skin) is shown in FIG. 4 . According to the graph, the result that the face (skin) irradiated with the positive and negative ions increased in the moisture content of the face (skin) with the irradiated time as compared with the face (skin) irradiated with only the blown air was obtained.
Comparative Example 1
[0062] The change of the moisture content of the face (skin) was measured by the same method as in example 1. However, the irradiated ions were only negative ions, and the ion concentration was regulated to 7000/cm 3 . The result of measuring the change of the moisture content of the face (skin) is shown in FIG. 5 . According to the result, in the case of irradiation of only the negative ions, the effect of increasing the skin moisture content was not obtained as compared with the face (skin) irradiated with only blown air.
Comparative Example 2
[0063] With the same method as in experiment 1, the change of the moisture content of the face (skin) was measured. However, the voltages which the high-voltage generation devices 4 and 5 applied to the ion generation electrodes (high-voltage application needle electrodes 1 and 2 ) and the pulse periods were regulated so that the concentration of the ions to be irradiated was 3000/cm 3 . The result of measuring the change of the moisture content of the face (skin) is shown in FIG. 6 . According to the result, by irradiation with the ion concentration of 3000/cm 3 , the effect of increasing the skin moisture content was not obtained as compared with the face (skin) irradiated with only blown air.
[0064] From the above described experiments, it has been found out that the moisture contents of the faces (skins) supplied with the positive ions and the negative ions having the compositions of the positive ions H 3 O + (m is 0 or an optional natural number) and the negative ions O 2 − (H 2 O)n (n is 0 or an optional natural number) with the ion concentrations set at 7000/cm 3 to 25000/cm 3 increase over time.
[0065] The reason why the ions are adsorbed by the face (skin) as above is considered to be because the nano-size water molecules which are generated by the positive ions and the negative ions having the compositions of the positive ions H 3 O + (H 2 O)m (m is 0 or an optional natural number) and the negative ions O 2 − (H 2 O)n (n is 0 or an optional natural number) which are supplied from the ion generation element being intensively hit against the skin, and are expressed by the following chemical formulas are effectively adsorbed by the skin.
[0000] H 3 O + +O 2 − →.OH+H 2 O 2 (1)
[0000] H 3 O + +O 2 − →.O 2 H+H 2 O (2)
[0000] 2H 2 O 2 →+2H 2 O+O 2 (3)
[0066] More specifically, it is estimated that by applying H + ions and O 2 − ions to the skin surface at the same time, —OH groups adhere to the skin surface, the skin surface is locally hydrophilized, water molecules easily penetrate through the skin, and bring about the effect of increasing the skin moisture.
[0067] As shown in the above embodiment, the positive and negative ions which are generated by an electric discharge increase the moisture contents in the human skin surfaces. Since the method increases the skin moisture content by positive and negative ions and does not use water, there is no increase of saprophytic bacteria, and since humidification is not performed, the humidity in a room is not elevated. Further, there is no need to condense moisture in the air, and therefore, the advantages that the device cost is not increased significantly, the power consumption is small, and the device is not upsized are provided.
Embodiment 2
[0068] Next, the experiment was conducted on change of the moisture content of a skin and skin elasticity by the air containing the positive ions and the negative ions generated by the ion generation element 60 and the air containing no such ions.
<Experiment Method>
[0069] The test was a single blind test randomization 2 plots cross-over test. Four days that are 3 days for the previous observation term and 1 day as the inspection day were set, and the test was carried out by dividing 16 women with normal and healthy bodies who were apt to feel drying of their skins into groups each with four people. The test plots were as follows.
[0070] Test plot 1: ion concentration 25,000/cm 3 (25,000 group)
[0071] Test plot 2: no ion (control group)
[0072] The temperature of the test room was regulated by an air-conditioner with 28° C. as the target. Further, the humidity was regulated by a desiccant type dehumidifier with 30 to 40% as the target.
[0073] The test subjects washed their faces with a cleansing milk and a facial cleansing foam, and after 60 minutes from the face washing, the test subjects were allowed to enter the test room. The test subjects were allowed to spend 140 minutes in total that are 20 minutes before operation of the test apparatus, 60 minutes after operation of the test apparatus, and 60 minutes after stoppage thereof, in the state in which the test subjects lay face up on their beds. This was carried out once in the morning and once in the afternoon. As for clothing on the inspection day, the test subjects wore the same T-shirts and sweat suits. The test subjects are instructed not to change their daily lives such as their eating habits and exercises up to then, and their daily lives were grasped by making them record their living situations such as sleeping hours, working hours, contents of meals, alcohol intake amounts, the use situation of medicines, physical conditions and the like in the day books everyday for 3 days before the inspection day. In consideration of the influence by meals, the same packed meals were taken by 21 o'clock as the dinner on the day before the inspection day, and intake of alcohol was prohibited. On the inspection day, the same meals were taken 1 hour before each of the inspections in the morning and the afternoon.
(a) Skin Moisture Content
[0074] 0 minutes, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes and 60 minutes after operating the ion generation device, and 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes and 60 minutes after stopping it, the skin moisture contents at the same spots at 1 cm sideway from the left eyes were measured by using Corrneometer CM825 (Integral Corporation, trade name). The result of measuring the change of the moisture contents of faces (skins) in this manner is shown in FIG. 7 . The graph shown in FIG. 7 shows the change over time of the moisture contents of the face irradiated with positive and negative ions (skin: shown by the black squares) and the face which were not irradiated with the positive and negative ions (skin: shown by the black circles).
[0075] According to the graph, the result was obtained, that the moisture contents of the faces (skins: shown by the black squares) irradiated with the positive and negative ions are continuously higher during irradiation with the positive and negative ions and after stoppage of the irradiation as compared with the faces (skins: shown by the black circles) not irradiated therewith.
(b) Skin Elasticity
[0076] 0 minute, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes and 60 minutes after operating the ion generation device, and 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes and 60 minutes after stoppage thereof, the skin elasticity R 5 (the restoration width for 0.1 seconds after starting release with respect to the suction width for 0.1 seconds after starting suction) and the skin elasticity R 7 (the restoration width for 0.1 seconds after starting release with respect to total suction width for two seconds) at the same spots 1 cm under the left eyes were measured by using Cutometer MPA580 (Integral Corporation, trade name). The result of measuring the change of the skin elasticity in this manner is shown in FIGS. 8A and 8B . The graphs shown in FIGS. 8A and 8B show the change over time of the skin elasticity of the face (skin) irradiated with positive and negative ions and the skin elasticity of the face (skin) which were not irradiated therewith.
[0077] According to the graphs, the result was obtained, that in the faces (skins: shown by the black squares) of the test plot 1 irradiated with the positive and negative ions, the skin elasticity was continuously improved during irradiation with the positive and negative ions and after stopping the irradiation as compared with the faces (skin: shown by the black circles) of the test plot 2 not irradiated therewith. The effect of the skin elasticity appeared slightly later as compared with that the increase in the skin moisture content appeared immediately after the irradiation, and therefore, improvement in the skin elasticity is estimated as the secondary effect by the increase of the skin moisture content.
[0078] By the above described experiment, the moisture content of the faces (skins) of the test plot 1 supplied with ions with the ion concentrations of the positive ions and the negative ions having the compositions of the positive ions H 3 O + (H 2 O)m (m is 0 or an optional natural number) and the negative ions O 2 − (H 2 O)n (n is 0 or an optional natural number) set as 25,000/cm 3 increases over time, and the skin elasticity (moisture retaining function of dermis) is improved therewith.
Embodiment 3
[0079] Next, a beauty apparatus using the above described ion generation element will be described.
[0080] A mode for carrying out the beauty apparatus will be described by using the drawing. In an embodiment shown in the drawing, the case of a facial care apparatus as a beauty apparatus will be described.
[0081] FIG. 9 is an explanatory view of a use state of a facial care apparatus (hereinafter, a facial care apparatus) 100 as a beauty apparatus. The facial care apparatus 100 is installed by being supported by a supporting member 101 . The facial care apparatus 100 generates positive ions and negative ions, and is used in such a manner as to irradiate the face of a user with the ions which are released.
[0082] A structure of the facial care apparatus 100 will be described.
[0083] As shown in FIG. 10 , the facial care apparatus 100 has a filter 160 , a blower 130 , a wind directing body 170 , an ion generation device 180 , a wind velocity detector 190 and the like mounted inside a casing 120 . Further, switches (not illustrated) which instruct operation of the devices such as the blower 130 , the ion generation device 180 and the wind velocity detector 190 , a control unit which controls drive of the blower 130 , the wind velocity detector 190 , the ion generation device 180 and the like, an operation display device (not illustrated) and the like are arranged inside the casing 120 .
[0084] When the blower 130 is operated, inflow air 110 a flows into the casing 120 from an inlet port 140 , passes through the wind directing body 170 , and includes ions generated from the ion generator 180 , and the air containing the ions is released from a release port 150 as released air 110 b.
[0085] Because the blower 130 and the ion generation device 180 are housed in a wind tunnel inside the casing 120 of the facial care apparatus 100 , the diameter of the casing 120 cannot be configured to be small. Accordingly, in order to generate ions and transfer/release the ions more efficiently by the air flowing in, the wind directing body 170 as will be described later is inserted into and placed inside the casing 120 .
[0086] A configuration of the wind directing body 170 will be described according to FIG. 11 .
[0087] The wind directing body 170 is installed at a downstream side of the blower 130 . The wind directing body 170 is formed into a disk shape which is fitted in the casing 120 , and a disk-shaped closure plate 171 which closes air which flows down is placed at a center portion. In a gap 173 between the closure plate 171 and the casing 120 , blade pieces 175 for turning the air which flows down are placed at a plurality of spots. The blade pieces 175 are installed to be inclined to change the flow of the passing air to turn it. In the embodiment, eight of the blade pieces 175 are disposed at the peripheral edge of the closure plate 171 and around the center axis of the casing 120 . The air which flows in by the blower 130 hits against the closure plate 170 , and the air current which has its way closed spouts to the downstream side from the gap 173 at the peripheral portion and flows down. At this time, the downflow direction of the air current changes along the inclination of the blade pieces 175 and the air current is turned. This embodiment has the configuration in which by the eight blade pieces 175 , the downflow air turns clockwise on the plan view shown by the direction A as shown in FIG. 11 .
[0088] The ion generator 180 is disposed at the downstream side of the wind directing body 170 .
[0089] FIG. 13 is an external view of the ion generation device. A voltage application needle electrode 1 which is connected to a high-voltage generation device and a ground electrode 3 are included, openings 183 for releasing the positive ions and negative ions generated from the ion generation element to outside are bored in a lid 181 . FIG. 14 is one example of a circuit of the ion generation device. The example shows a mode in which a drive circuit 63 and an ion generation unit 60 of the device are connected via a transformer 65 . In the embodiment, the illustrated ion generation device is exemplified, but as the ion generation device, other ion generation devices also can be used as long as the ion generation devices can generate the aforementioned positive and negative ions.
[0090] The wind velocity detector 190 is mounted in the vicinity of the blowoff port 150 at a downstream side of the ion generation device 180 . FIG. 15 shows an example of a circuit of the wind velocity detector. The wind velocity detector 190 keeps a thermistor 195 self-heating, and the temperature of the thermistor 195 is reduced when an air current passes the thermistor 195 . The wind velocity is detected by the temperature reduction. For detection of a wind velocity, there are a hot wire type and a thermistor type. Any type of the conventional wind velocity detectors can be used besides the illustrated type, and a similar effect is provided.
[0091] The number of ions which can be released from the ion generation device 180 is significantly influenced by the velocity of the wind which passes through the vicinity of the discharge electrodes. More specifically, the velocity of the wind in the vicinity of the electrodes is higher, the number of the ions which are released increases more. Accordingly, the wind velocity needs to be increased as much as possible in the vicinity of the ion generation device 180 . Meanwhile, the upper limit of the velocity of the wind which is fed from the blowoff port 150 is approximately 1 m at the utmost to suppress drying of a face (skin). Thus, the present facial care apparatus has the wind velocity detector 190 installed at the blowoff port 150 , detects the wind velocity in the vicinity of the blowoff port 150 , and controls the velocity of the wind to be blown off.
[0092] The quantity of the air passing through the passage gap 173 (wind directing body 170 ) and the quantity of the air which is fed from the blowoff port 150 are basically the same. Therefore, the wind velocity in the vicinity of the ion generation device 180 is increased by narrowing the passage gap 173 , and the sectional area of the blowoff port 150 is made larger than the passage gap 173 , whereby the velocity of the wind which is fed from the blowoff port 150 can be made low. The air is compressed by the blowoff port 150 where the diameter of the casing is made smaller than the other casing diameter. The air current blown from the blowoff port temporarily causes contraction in the vicinity of the blowoff port 150 , but thereafter, tends to be expanded. However, if the blowoff (release) wind velocity is made too low, the air current does not directly reach the object (face). In order to cause the air current to reach a distant place, it is effective not to expand the air current, and therefore, expansion of the air current which is blown off is suppressed by turning the downflow air current by the wind directing body 170 .
[0093] FIG. 12 schematically shows the behavior of the ions in the vicinity of the blowoff port.
[0094] The air which is enhanced in the downflow velocity with the downflow direction changed by the blade pieces 175 includes the ions (positive and negative ions) generated from the ion generation device 180 , and the air containing the positive and negative ions (white circles and black circles) with high density is released from the blowoff port 150 to an ion compressed region 20 as illustrated. At this time, the port diameter of the blowoff port 150 is formed to be larger than the passage gap 173 , whereby the release velocity is reduced. Further, the air which is blown from the blowoff port 150 changes (turns) the downflow direction by the blade pieces 175 , and therefore, is configured to reach a face in the state with high-density ions without being expanded.
[0095] As above, in the facial care apparatus 100 , the inflow air 110 a taken in from the inlet port 140 by rotation of the fan 130 installed at the upstream side of the inside of the casing 120 is released as the released air 110 b from the blowoff port 150 at the most downstream side. The air which flows in from the inlet port 140 during this while passes through the filter 160 , has the flow direction changed by the wind directing body 170 , includes the ions generated from the ion generation device 180 and is released to the external air from the blowoff port 150 .
[0096] An operation of the facial care apparatus of the above described explanation will be described hereinafter.
[0097] When the operation switch (not illustrated) of the facial care apparatus 100 is turned on, the blower 130 and the ion generation device 180 are operated. The external air is sucked into the facial care apparatus 100 , the sucked air is fed to the ion generation device 180 via the filter 160 and the wind directing body 170 . The air enhanced in wind velocity by the wind directing body 170 passes through the vicinity of the ion generation device 180 to thereby become the air containing many ions, and the air containing the ions is compressed and blown from the blowoff port 150 with the port diameter made smaller than the other diameters of the casing. The ions shown by the positive ions (for example, the white circles) and the negative ions (for example, the black circles) generated by the ion generation device 180 are carried by the air current which is turned and flows in to head for the blowoff port 150 . The air is compressed in the narrow blowoff port 150 , and the air which contains the ions with high density is released to the ion compressed region 20 shown by the dashed line. Because the air which includes the ions and flows down is in the turned state by the blade pieces 175 , the air keeps the compressed state, and does not expand and is not reduced in the release speed in the ion compressed region 20 .
[0098] The ions contained in the air which is supplied from the facial care apparatus 100 have the compositions of the positive ions H 3 O + (H 2 O)m (m is 0 or an optional natural number) and the negative ions O 2 − (H 2 O)n (n is 0 or an optional natural number) as described in embodiment 1. It is conceivable that the positive ions and the negative ions of a high concentration having the compositions intensively hit against a face (skin), whereby nano-size water molecules are generated on the skin surface as expressed by the following chemical formulas described above, and the water molecules are effectively adsorbed by the skin.
[0000] H 3 O + +O 2 − →.OH+H 2 O 2 (1)
[0000] H 3 O + +O 2 − →.O 2 H+H 2 O (2)
[0000] 2H 2 O 2 →2H 2 O+O 2 (3)
[0099] The facial care apparatus 100 of the present invention is of a method which uses water generated by the chemical reactions as described above, and does not directly spray water. Therefore, the velocity of the air current hitting a skin and the concentration of ions are important. Further, if the air current (air blow) is too fast, the skin is dried due to the air current.
[0100] Unlike an ordinary hair drier and air-conditioner such as an air cleaner, in the facial care apparatus of the present invention the face of a user in close proximity is the target, and therefore, the air current which is let off is required to be strictly “gentle”. A distance L from an assumed target (face of a user) is around 30 cm. The velocity of the wind hitting the face is required to be approximately 1 m at the maximum. Therefore, it is necessary to blow air while detecting the velocity of the air current to be fed.
[0101] Thus, generation of ions and the wind velocity will be described.
[0102] The number of ions which can be fed out of the ion generation device 180 is significantly influenced by the velocity of the wind which passes through the vicinity of the discharge electrodes. More specifically, as the wind velocity is higher, the number of ions which are released increases more. Accordingly, the wind velocity needs to be increased in the vicinity of the ion generation device 180 . Meanwhile, the upper limit of the velocity of the air which is released from the blowoff port 150 is approximately 1 m at the utmost as described above. Because the casing 120 of the facial care apparatus 100 cannot be configured to be thin for the reason of housing the blower 130 and the ion generation device, the wind velocity in the region of the ion generation device 180 is enhanced by contracting the air current by the wind directing body 170 , and ions are efficiently transferred.
[0103] As above, in the facial care apparatus 100 , the passage gap 173 of the wind directing body 170 is narrowed to increase the wind velocity in the vicinity of the ion generation device 180 to increase generation of ions, and the sectional area of the blowoff port 150 is made larger than the passage gap 173 to reduce the velocity of the wind which is blown from the blowoff port 150 , while in order to cause the air current which is blown from the blowoff port 150 and contains positive and negative ions to reach a distant place, the air current is turned with the blade pieces 175 of the wind directing body 170 and the wind velocity of the blowoff port 150 is kept.
Embodiment 4
[0104] An embodiment includes an ion detector 200 in addition to the configuration of the beauty apparatus described in embodiment 3. The ion detector 200 is controlled to detect ions released by the control unit not illustrated if there is ion release of a predetermined value or more.
[0105] The air which is released from the blowoff port 150 has the number of ions contained therein abruptly decreased as the distance becomes farther. Further, the number of ions is influenced by the wind blowing velocity, and therefore, the wind blowing velocity is determined by an experiment. In the embodiment, the ion generation device and the wind velocity are regulated so that the number of ions is 7,000/cm 3 on a human face surface.
[0106] The number of ions released from the ion generation device is also influenced by the frequency of a high voltage which is applied to the discharge electrodes, besides being significantly influenced by the wind velocity as described above. In general, as the frequency is higher, the number of ions which are released increases more. The number of ions which are generated differs according to a discharge type and an electrode shape, and therefore, the conditions are set in the device which is decided to be used in advance. A drive circuit of the ion detector as a one example of the mode of carrying out the invention is shown in FIG. 17 . In the circuit, R 1 is set as 1 GΩ, R 2 to R 5 are set as 10 kΩ, C is set as 1000 pF and Vcc is set as 5 V.
[0107] Next, control of the facial care apparatus 100 will be described according to FIG. 16 .
[0108] When the operation switch 105 is inputted, control signals are outputted to the blower 130 , the ion generator 180 , and a display device 125 from a control unit 107 . The control unit 107 is configured to output control signals to the blower 130 and the ion generation device 180 and control the wind velocity/ion concentration and the like of the air released from the facial care apparatus 100 , when the wind velocity detector 190 detects the wind velocity which is a set wind velocity or more or the set wind velocity or less, and when the ion detector 200 detects an ion concentration of a value other than the set value.
INDUSTRIAL APPLICABILITY
[0109] By installing the facial care apparatus of the present invention at bedding, a skin is not dried during sleep, and a beauty effect can be obtained. Suspended bacteria can be removed by ions, and therefore, the environment with purified air can be supplied.
REFERENCE SIGNS LIST
[0000]
1 voltage application needle electrode (positive ion generation electrode)
2 voltage application needle electrode (negative ion generation electrode)
3 ground (counter) electrode
4 high-voltage generation device
5 high-voltage generation device
6 ion generation apparatus
7 blowing fan
20 ion compressed region
60 ion generation element
100 facial care apparatus
130 fan
140 suction port
150 blowoff port
160 filter
170 wind directing body
180 ion generation device
190 wind velocity detector
200 ion detector | A method for increasing a moisture content of a skin and improving skin elasticity by improving a moisture retaining function of a dermis without generating steam, mist and the like, and a beauty apparatus that supplies moisture to a skin are provided. A user is irradiated with positive and negative ions which are generated by using ion generation means 6 and carried by a low-speed air current from a blower 7, and a concentration of the ions for irradiating a skin surface is elevated to be a predetermined value or more, whereby the positive and negative ions react to produce water, which moistens the skin, and improves skin elasticity. Further, when the ions supplied from the ion generation means 6 is released from a blowoff port 61, the blowing speed is controlled at a low level while elevating the ion concentration. | 0 |
TECHNICAL FIELD
The invention relates to the technical field of electronics, more specifically, to a digital electret microphone and the connection structure thereof.
BACKGROUND OF THE INVENTION
The digital electret microphone is provided with an analog-to-digital conversion on the basis of traditional electret microphone, in order to output the digital electric signal and increase the ability of anti-electromagnetic interference for the microphone and improve the quality of output signal of the microphone. However, being different from the two pin structure of the traditional electret capacitance microphone, the connection terminals of the digital electret capacitance microphone are 4 pin, which respectively are: Power Input End VDD, Clock Input End CLK, Data Output DATA and Ground Terminal GND. In the prior art, the 2 connection pins of the circular patch packaging structure of the traditional electret capacitance microphone adopts the ring structure to make it easy to implement surface mount technology. However, if the 4 pin digital electret capacitance microphone adopts the circular packaging structure either, it is difficult to implement the automatic surface mount technology. So the people skilled in the art has to set the digital electret capacitance microphone as a square packaging structure to make it easier to implement the automatic surface mount technology, which wastes the existed production line of the circular patch packaging and increases enterprise production cost.
SUMMARY OF THE INVENTION
The invention aims to provide a connection structure of a digital electret microphone for solving the above technical problems.
The invention also aims to provide a digital electret microphone for solving the above technical problems.
The technical problems solved by the invention can be implemented by the following technical proposal:
A connection structure of a digital electret microphone, which is used to mount the digital electret microphone on a printed circuit board, wherein the digital electret microphone has a circular packaging structure, the connecting surface of the circular packaging structure has at least five pins; the PCB has a circular mount field provided with at least four bonding pads, the five pins are in contact with the four bonding pads.
Preferably, wherein the pins includes a first pin located at the center of the circle, a second pin surrounding the first pin, a third pin, a fourth pin and a fifth pin configured between the first pin and the second pin at equal interval.
Preferably, the bonding pad includes a first bonding pad located in the center of the circular mount field, a second bonding pad which embraces the first bonding pad, a third bonding pad and a fourth bonding pad which are between the first bonding pad and the second bonding pad. The third bonding pad and the fourth bonding pad are set in an opposite position.
Preferably, the first pin is in contact with the first bonding pad, the second pin is in contact with the second bonding pad;
At least one of the third pin, the fourth pin and the fifth pin is in contact with the third bonding pad, at least one of the third pin, the fourth pin and the fifth pin is in contact with the fourth bonding pad.
Preferably, the third pin, the fourth pin and the fifth pin are three sections of the first category of the curved connection structure which embrace the circular structure of the first pin. The three sections of the first category of the curved connection structure are set with the same pace.
Preferably, the third bonding pad and the fourth bonding pad are two pieces or the second arc-shaped connection structure which surrounds the same circular structure of the first bonding pad.
Preferably, the length of the third bonding pad is greater than that of the third pin, the fourth pin or the fifth pin; the length of the fourth bonding pad is greater than that of the third pin, the fourth pin or the fifth pin.
The present invention further provides a digital electret microphone, comprising the connection structure of the digital electret microphone as disclosed above, the third pin is the data output end, the fourth pin is the clock input end, the fifth pin is the controlled switch terminal. The fifth pin is in contact with the third pin or the fourth pin under the influence of a control signal, so that the pin and the corresponding bonding pad can be properly linked with each other;
Preferably, the determining circuit generates the control signal based on the signal input or output status the pin.
Preferably, the determining circuit located in the interior of the digital electret microphone is in contact with the third pin, the fourth pin and the fifth pin.
Preferably, the first pin and the first bonding pad are the power input end, both the second pin and the second bonding pad are the ground terminal; alternatively both the first pin and the first bonding pad are the ground terminal, both the second pin and the second bonding pad are the power input end.
By adopting the above-mentioned technical solutions, the present invention is able to achieve the adaptive mounting for the circular packaging structure of the digital electret microphone, reuse the existed production line process, and reduce the enterprise producing cost.
BRIEF DESCRIPTIONS OF THE DRAWINGS
FIG. 1 illustrates a structure schematic of the pin distribution of the connection surface of the digital electret microphone in the present invention;
FIG. 2 illustrates a structure schematic of the pan distribution of the circular mount field of the printed circuit board in the present invention;
FIG. 3 illustrates a structure schematic of internal system structure of the digital electret microphone in the present invention.
DETAILED DESCRIPTION
The technical proposal in the present invention will be described clearly and completely in combination with the following Figures. Obviously, the embodiment, which is described before, is only part of the embodiments, not whole embodiments in the present invention. Based on the embodiment in the present invention, the common artisan of this field getting all other embodiments without creative working, are in the protection of the invention.
It should be noted that without conflict, the embodiment and the character of the embodiment can be combined each other in the present invention.
The present invention will be further illustrated in combination with the following Figures and embodiments. However, it should not be deemed as limitations of the present invention.
Referring to FIGS. 1 and 2 , a connection structure of digital electret microphone, which is used for mounting the digital electret microphone 1 on a PCB 2 , wherein the digital electret microphone 1 has the circular packaging structure, of which there is at least five pins of the connection surface; the PCB 2 has a circular mount field, on which there is at least four bonding pads, the five pins are in contact with the four bonding pads.
Preferably, as the embodiment of the invention, the pin includes the first pin 11 located at the center; the second pin 12 which embraces the first pin 11 ; the third pin 13 , the fourth pin 14 and fifth pin 15 which are between the first pin 11 and the second pin 12 with the same pace.
Preferably, as the embodiment of the invention, the pad includes the first bonding pad 21 located in the center of the circular mount field, the second bonding pad 22 which embraces the first bonding pad 21 , the third bonding pad 23 and the fourth bonding pad 24 which are between the first bonding pad 21 and the second bonding pad 22 . The third bonding pad 23 and the fourth bonding pad 24 are set in an opposite position.
Preferably, as the embodiment of the invention, the first pin 11 is in contact with the first bonding pad 21 , the second pin 12 is in contact with the second bonding pad 22 .
At least one of the third pin 13 , the fourth pin 14 and the fifth pin 15 is in contact with the third bonding pad 23 , at least one of the third pin 13 , the fourth pin 14 and the fifth pin 15 is in contact with the fourth bonding pad 24 .
Preferably, according to one embodiment of the invention, the third pin 13 , the fourth pin 14 and the fifth pin 15 are three sections of the first category of the curved connection structure which embrace the circular structure of the first pin 11 . The three sections of the first category of the curved connection structure are set with the same pace. As a concrete embodiment, the length of the first category of the curved connection structure is one six circle length of the same circular structure.
The third pin 13 , the fourth pin 14 , the fifth pin 15 of the present invention can adopts other shapes of connection structure as long as they are set between the first pin 11 and the second pin 12 . To meet the needs of the invention, the third pin 13 , the fourth pin 14 , the fifth pin 15 can be the glyph arrangement.
Preferably, as the embodiment of the invention, the third bonding pad 23 and the fourth bonding pad 24 are two sections of the second category of the curved connection structure which embrace the circular structure of the first bonding pad 21 . The length of the second category of the curved connection structure is smaller than the half circle length of the same circular structure but greater than the length of the first category of the curved connection structure.
In the same way, the third bonding pad 23 and fourth bonding pad 24 of the invention can adopt other shape of pan, as long as they are used for the propose of the invention.
The shape and size of the three sections of the first category of the curved connection structure are equal, the shape and size of the two sections of the second category of the curved connection structure are equal.
Preferably, as the embodiment of the invention, the length of the third bonding pad 23 is greater than any length of the third pin 13 , the fourth pin 14 and the fifth pin 15 ; the length of the fourth bonding pad 24 is greater than any length of the third pin 13 , the fourth pin 14 and the fifth pin 15 .
In the present invention, both the first pin 11 and the first bonding pad 21 are the power input end, both the second pin 12 and the second bonding pad 22 are the ground terminal; alternatively both the first pin 11 and the first bonding pad 21 are the ground terminal, both the second pin 12 and the second bonding pad 22 are the power input end.
The invention also provide a digital electret microphone 1 which has the connection structure mentioned above, whose third pin 13 is the data output, the fourth pin 14 is the clock input end, the fifth pin 15 is the controlled switch terminal. The fifth pin 15 gets in contact with the third pin 13 or the fourth pin 14 by the effect of a control signal, so that the correct connection is achieved between the pin and the corresponding pad.
The control signal is generated by a determining circuit 16 , the determining circuit 16 depends on the input or output status of the signal of the pin to generate the control signal.
Preferably, as the embodiment of the invention, the determining circuit 16 is located in the interior of the digital electret microphone 1 . The determining circuit gets in contact with the third pin 13 , the fourth pin 14 and the fifth pin 15 by electric.
The determining method for the digital electret microphone of the present invention includes the following steps:
The determining circuit determines the connection of the pin and pad based on the input of the clock signal of the external circuit, the decisions of the determining circuit are described as follows:
The third
The third pin
The fourth
The fourth pin
bonding pad
The third pin and the fifth pin
bonding pad
and the fifth
The third pin and the fourth pin
pin
The third
The fourth pin
The fourth
The third pin
bonding pad
The fourth pin and the fifth pin
bonding pad
and the fifth
The fourth pin and the third pin
pin
The third
The fifth pin
The fourth
The third pin
bonding pad
The fifth pin and the third pin
bonding pad
and the fourth
The fifth pin and the fourth pin
pin
The fourth
The third pin
The third
The fourth pin
bonding pad
The third pin and the fifth pin
bonding pad
and the fifth
The third pin and the fourth pin
pin
The fourth
The fourth pin
The third
The fourth pin
bonding pad
The fourth pin and the fifth pin
bonding pad
and the fifth
The fourth pin and the third pin
pin
The fourth
The fifth pin
The third
The third pin
bonding pad
The fifth pin and the third pin
bonding pad
and the fourth
The fifth pin and the fourth pin
pin
In the first situation, the determining circuit determines whether one of the third pin, the fourth pin, the fifth pin has been input the signal, so that the pins received the signal can be the clock input end.
If there is a pin received the clock signal, the other two pins can be set as data output.
If there are two pins received the signal, the determining circuit sets both the two pins as the clock input, and sets the rest one as data output to output the digital signal.
If the third bonding pad outputs the clock signal as the table described above:
1) When only the third pin receives the clock signal, sets the fourth pin and the fifth pin as data output together. 2) When the third pin and the fifth pin are received the clock signal either, sets the fourth pin as the data output. 3) When the third pin and the fourth pin are received the clock signal either, sets the fifth pin as the data output, because the fifth pin is set as controlled switch terminal by default, the controlled switch terminal cuts over the internal circuit by the effect of a control signal to output the digital signal.
In second situation, the determining circuit sets the third pin as the data output, determines whether the third bonding pad or the fourth bonding pad receives the signal, then it thoughts the pan received the signal as the one connected to the third pin, and sets the other pan as the clock input end, which sends at least one clock signal to the fourth pin or the fifth pin.
Then, the determining circuit checks whether the fifth pin has received the clock signal, if not, the determining circuit sets the third pin and the fifth pin as the data output together, or sets the third pin as the data output separately; if yes, the determining circuit sets the fifth pin and the fourth pin as the clock input end together, or sets the fifth pin as the clock input end, as the table listed above.
1) When the fourth bonding pad gets in contact with the third pin separately, the fourth bonding pad receives the digital signal, the third bonding pad gets in contact with the fourth pin and the fifth pin. The fourth pin and the fifth pin can be the clock input end together. 2) When the fourth bonding pad gets in contact with the third pin and fifth pin, the third pin and fifth pin can be the data output together, the fourth pin can be the clock input separately. 3) When the fourth bonding pad gets in contact with the third pin and the fourth pin, the third pin and fourth pin can be the data output together; the fifth pin can be the clock input end separately. Of course, the controlled switch cuts over internal circuit by the effect of the control signal to receive the external clock signal.
The other situations are same as these ones and it would not be described any more.
The disclosure described above is preferred embodiment, it does not limit the method and scope of the invention. It should be understood that the proposal obtained from the equivalent replacement and apparent modifications through the instruction and figure of the invention will be covered within the scope of the invention to those skilled in the art. | The invention relates to the technical field of voice processing equipment, more specifically, to a microphone. A new-type microphone structure comprises a first layer structure, a second layer structure located on the first layer structure, a microphone acoustic cavity formed by the first layer structure and the second layer structure, at least one acoustic hole for acquiring sound signals, which is arranged on the microphone acoustic cavity, and a dustproof component which covers the inside of the acoustic hole. The invention can prevent most of the dust particles and the moisture and the siphoning effect when in actual use, which does not need to change the size of the existing microphone. It can be used in thin structures, and can prolong the service life of the microphone. | 7 |
This is a substitute application for Ser. No. 08/832,111, filed Apr. 3, 1997, now abandoned.
BACKGROUND OF THE INVENTION
A fishing hook swallowed by fish may need to be removed from the fish for a variety of reasons. One reason may be to simply retrieve the hook from the caught fish and then store it. Another reason may be to measure the fish and, if below a predetermined size or weight level, set by law, release the fish back into the water. In either event, hook removers or extractors have been developed to perform this function to prevent injury by the hook ends to the user's fingers. Some hook removers consist of an elongated straight bar with one or more hook holding members at their ends. Others may incorporate a scale to weigh the fish and/or a measuring scale to measure its length.
The present invention provides for a hook remover mounted on a measuring scale used to measure the length of the fish, and in which an outer scale can be extended beyond its normal length by pulling on an inner measuring scale located within it as described herein.
DESCRIPTION OF THE PRIOR ART
Fish hook removers are known in the prior art. For example, U.S. Pat. No. 2,348,662 to Stevens discloses a straight bar hook extractor having a hook engaging member on one of its ends with a smooth fish line engaging member on the other end.
U.S. Pat. No. 2,630,314 to Cadwallader combines a fishing knife with a gaff hook, a fish scaler and a weighing scale.
U.S. Pat. No. 3,115,722 to Mann discloses a multi-purpose fishing tool having a fishing pole ground stake, a hook remover, a length measuring scale and means to clip the tool to a fishing rod.
U.S. Pat. No. 3,434,231 to King discloses a fishing tool having a ruler, scaler, hook remover and a plug and fly remover.
The present invention differs from the known prior art by providing for a fish hook removing tool which can weight and measure a caught fish wherein the length of an outer measuring scale can be extended by an inner measuring scale as further described in this specification.
SUMMARY OF THE INVENTION
This invention relates to a fishing hook remover tool having an outer length measuring scale whose length measuring can be extended by an inner length measuring scale. The inner scale has an end unit that can also be used to hold a fish and means to weigh the held fish.
It is the primary object of the present invention to provide for an improved tool that can remove a fish hook and measure the length of the caught fish.
Another object is to provide for such a tool that can also weigh the caught fish.
These and other objects and advantages of the present invention will become apparent to readers from a consideration of the ensuing description and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the invention's preferred embodiment.
FIG. 2 is a the same view as in FIG. 1 with part of the rear outer section cut away to show its inner components.
FIG. 3 shows a perspective view of FIG. 1 with the inner length and weight measuring scale extended and most of its upper outer section removed.
FIG. 4 shows an enlarged view of a section of the two scales used on the FIG. 3 extended inner scale.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a perspective view of the invention's preferred embodiment. The elongated straight cylindrical plastic hollow rod casing 1 has a measuring length scale along its outer surface, which is measured in inches and can be used to measure the length of a caught fish. At the rod's rear end is a removably attached nosepiece hook remover 5. This remover has a "V" shaped opened cut out 7 cut into the center of the remover with a longer "V" shaped cut out portion 9 on its underneath side, as shown in dotted lines in FIG. 1.
The remover 5 is angled about 15 degrees upwardly from an extended side of the straight rod's casing side. This angular variant is shown as the angle α in FIG. 1 and assists the nosepiece remover in the removal of a fishhook from the intestines of a caught fish. Located on the underside of the rod casing 1 is a depending eye hook 11 for holding the fishing line and assisting in the removal of the fish hook.
A screw on internally threaded front cap 13 acts to retain a internal compression spring housed within the hollow rod casing 1. The cap has inner threads which engage outer threads on the rod's front, outer surface. Extending from the same front end is the weight holding measuring hook 15 which is part of an inner measuring scale used to retain the spring as explained hereafter. By pulling on the hook 15, either by the weight of a fish or by hand, an inner measuring scale concealed within the hollow of rod casing 1 is visually displayed indicating the weight (or amount of force used in pulling) on the fish hook. As further explained hereafter this inner scale also has measurement indicators along one of its sides to permit the measurement of fish exceeding the length imprinted or posted on the scale 3 outside of the rod. For example, if 12 inches is the maximum shown length that the outer length measuring scale indicates, as shown, then measurements over 12 inches could be made by pulling out, in the direction of the arrow, the inner scale attached to the hook 15.
FIG. 2 is the same view as in FIG. 1 with the upper part of the rear, outer rod section cut away to show its inner workings. The circular stop plate 17 is located near the end of the dual function inner measuring scale 19. Inner measuring scale 19 is a flat elongated ruler member whose front end is the exposed hook 15 which extends through a rectangular slot 23 in the screw-on retaining cap 13.
The center portion 24 of inner scale 19 may be left opened to form a rectangular cut out to mount the compression coil spring 21 and reduce the scale's weight. The outer diameter of coil spring 21 is greater than the height of slot 23 to prevent it from passing through when compressed against the cap. When end hook 15 is moved to the left, the inner scale 19 moves with it, but the seated spring 21 is compressed by it and retained by the cap 13 in the process. Appropriate extending side stops 22 on the two sides of scale 19 prevent it from passing completely through the slot 23 when fully extended. Lower eye hook 11, used to guide and retain a stretched fishing line extending from the hook to the user's reel (not shown), is rigidly attached to the underside of the hollow rod casing 1.
FIG. 3 shows a perspective view of FIG. 1 with its inner length and weight measuring scale 19 extended, and most of the upper part of the rod's outer casing 1 removed. In the extended position the stop 17 stays at the back while the inner scale 19 and its seated spring 21 is compressed between it and the front retaining cap 13. The extended part of inner scale 19, outside of the rod casing 1, has two opposite side scales 25 and 27 stamped along its length. Scale 25 represents the weight markings in pounds (LBS) of a fish hung from the end hook 15 under the pull of gravity.
The other scale 27 has extended length markings starting from the highest markings of the outer scale 3 (e.g., 12 inches) and ending at the highest exposed length of the inner scale such as 24 inches. Thus, fish in length up to 24 inches, or a higher amount depending on the length of casing 1, can be measured by the scale markings 3 on the outer casing or, if a greater length than those on the outer scale markings 3, by the extended inner scale markings 27.
FIG. 4 shows an enlarged view of a portion of the two opposite side scale markings used on the FIG. 3 extended inner scale element 19. Clearly, the specific units used to measure a fish's length and weight could by design choice be different or a combination of different values such as inches/centimeters or pounds/grams.
In one embodiment the hollow rod casing 1 was made of an injection molded ABS (Acrylonitrile-butadiene-styrene) plastic material approximately 15 inches in overall length with a diameter of 3/8 of an inch. The outer length scale 3 is 12 inches. The hook remover 5 is about 3 inches in length with a 15 degree angled "V" shaped cut out 7. The inner scale 19 is made of a flat stainless steel bar with a center opening and with stamped scale markings on its two opposite side edges for the scales 25 and 27.
In use, a user would hold the casing 1 in one hand, with the fish in the other hand while keeping tension on the fishing line 29, shown in dotted lines in FIG. 3. Next, the user would insert the front opened V shaped notch 7 inside the fish's mouth to engage the hook end and push downwardly to remove the hook. Once the hook is removed from the fish, the fish may be measured on scale 3 or, if larger than its scale allows, by the extended inner scale 27. To weigh the fish it is hung by the hook 15 through its side gill and mouth to compress the spring 21 while the casing 1 is maintained in a generally vertically disposed orientation. A reading on the inner scale exposed marking 25 indicates the fish's weight in the units marked.
The primary components of the fish hooker remover tool, including the rod casing 1, the screw on cap 13 and the outer casing numbers, would best be manufactured of ABS plastic using the injection molding process. Injection molding is a plastic molding process whereby heat softened plastic material is forced under very high pressure into a metal cavity mold, usually aluminum or steel, which is relatively cool. The inside cavity of the mold is comprised of two or more halves, and is the same desired shape as the product to be formed (in this case the hollow casing, its front retaining cap and casing scale markings). High pressure hydraulics are used to keep the mold components together during the actual injection phase of the molding process. The injected plastic is allowed to cool and harden in the mold. The hydraulics holding the multiple component mold cavity together are released, the mold halves are separated and the solid formed plastic item is removed. Injection molding can be highly automated process and is capable of producing extremely detailed parts at a very cost effective price. The process should be invaluable in producing this invention's fish hook remover tool cost effectively.
The flat, stainless steel inner scale 19 can be manufactured using the metal stamping and punching processes including the numbers stamped on its two side scales. Metal stamping is a process whereby flat metal is formed between two parts of a die under tremendous pressure. The metal can be punched, formed and shaped in these dies, many times in one process, and spot welding of separate components can be employed to complete the assembly of sheet metal components. The stamped metal used for the inner scale may be stainless steel or plated carbon steel to prevent rusting.
The weight measuring compression spring 21 is an "off the shelf" commercially available component. The Thomas Register of American Manufacturers is a good resource for locating manufacturers and supplies of such commercially available components.
The spring is assembled by first placing the spring inside the stamped stainless steel inner scale 19 which is inside the hollow casing 1. Next, the retaining cap 13 is screwed on the casing's front end with its front hook 15 exposed. The rear hook 5 can be mounted on the other end of the casing 1 by external casing threads that engage internal hook end threads.
Although the present invention's preferred embodiment and the method of using the same according to the present invention has been described in the foregoing specification with considerable details, it is to be understood that modifications may be made to the invention which do not exceed the scope of the appended claims and modified forms of the present invention done by others skilled in the art to which the invention pertains will be considered infringements of this invention when those modified forms fall within the claimed scope of this invention. | A fishing hook removing tool having a hollow outer casing with an outer length measurement scale and an inner movable scale. Length measurements on the inner scale, when extended from the outer casing, are additive to those on the outer casing. This allows the length measurement of fish greater than the total length of the outer casing measurement scale. The rear end of the outer casing has a V shaped hook remover with one side of the V being greater than the other. In addition, the inner scale may have weight measurement units on one side and a compression spring within the outer casing to permit the weighing of a fish. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates generally to a cassette used to hold medical or dental instruments, and more particularly, to a cassette used to hold medical or dental instruments which permits the cleaning, sterilization, and storage of such instruments while housed in the cassette.
Medical or dental instruments must be sterilized before they are used. Typically, after each use, the instruments are secured in a holder known as an instrument cassette. Thereafter, the instrument cassette, along with the medical or dental instruments therein, is placed into a cleaning system wherein residual substances from a previous medical or dental procedure are removed from the instruments.
The instrument cassette is subsequently rinsed to remove any residual cleaning solution. After the instrument cassette has dried, the cassette is enveloped with a sterile wrap. The sterile wrap is impermeable to many airborne contaminants and pathogens.
After being wrapped, the instrument cassette is placed in a sterilizing chamber, such as an autoclave, wherein the instrument cassette is subjected to steam at high temperatures in order to eliminate any microbial contamination that may remain on the instruments from their previous use.
After being removed from the sterilizing chamber, the instrument cassette may be stored, with the sterile wrap remaining thereon, until the instruments are next needed. During the storage process, the sterile wrap continues to function as an impermeable barrier between the instruments within the instrument cassette and airborne contaminants and pathogens that may be present in the surrounding environment.
The integrity of the sterile wrap must therefore be maintained in order for it to function properly. For example, if the sterile wrap is torn, an aperture is created through which airborne contaminants and pathogens can reach the instruments within the cassette thus compromising the sterile condition of the instruments.
It is therefore important for the outer surfaces of an instrument cassette to be free of jagged edges and projecting components. One source of jagged edges and projecting components is the latch used to lock the two halves of the cassette together. Often, a portion of the latching mechanism projects abruptly away from the body of the cassette. This creates a surface which can tear the sterile wrap.
The following patents disclose some cassette designs which have been heretofore developed. U.S. Pat. No. 5,505,916 issued to Berry teaches an autoclave cassette 20 with two substantially similar tray halves 21 and 22. A slide portion 24 extends out of the autoclave cassette 20 and receives a retainer portion 25 for the purpose of locking the autoclave cassette.
Moreover, U.S. Pat. No. 5,346,677 issued to Risk teaches an instrument cassette 10 with a lower tray 12 and an upper tray 14. A tab portion 64 extends outwardly from the upper tray 14. The tab portion 64 cooperates with a locking stud 59 to lock the cassette 10.
Further, U.S. Pat. No. 5,284,632 issued to Kudla et al. discloses a cassette 20 with an upper tray 46 and a lower tray 22. A latch plate 66 extends outwardly from the lower tray 22 and receives a latch button 68 to lock the trays 46 and 22 together.
Some of the aforementioned designs include latch mechanisms which contain components that possess edges on which the sterile wrap used to envelop the cassette could be torn. Additionally, some of the aforementioned designs are complex, and are therefore difficult and expensive to manufacture.
What is needed therefore is a medical or dental cassette that is configured to eliminate projecting components which could readily tear the sterile wrap used to envelop the cassette. What is further needed is a medical or dental cassette which is simple and inexpensive to manufacture.
SUMMARY OF THE INVENTION
In accordance with one embodiment of the present invention, there is provided an instrument cassette and sterile wrap assembly. The assembly includes a base having an upright sidewall and a horizontal bottom wall, the upright sidewall having a lower slot and an upper aperture defined therein. The assembly further includes a latch member having a lower section, an intermediate section and an upper section, wherein (1) the lower section extends through the slot defined in the base, (2) the intermediate section is substantially planar, and (3) the upper section (i) extends through the upper aperture defined in the base, and (ii) has a slot defined therein. The assembly also includes a lid having a horizontal top wall and a tongue member attached thereto, wherein the tongue member extends through the slot defined in the upper section of the latch member when the lid is latched to the base. Further, the assembly includes a sterile wrap which envelops the base, the latch member and the lid, wherein the sterile wrap is juxtaposed to the bottom wall of the base, an entire first side of the intermediate portion of the latch member, and the top wall of the lid.
Pursuant to another embodiment of the invention, there is provided a method of protecting an instrument cassette having a lid, a base and a latch member. The method includes, firstly, latching the lid to the base with the latch member, wherein (1) the base has a horizontal bottom wall, (2) the lid has a horizontal top wall and a tongue member attached thereto, and (3) the latch member includes (i) a lower section fixed in position relative to the base, (ii) a planar intermediate section, and (iii) an upper section which cooperates with the tongue member of the lid to latch the lid to the base, and secondly, wrapping the lid, the base and the latch member with a sterile wrap so that the sterile wrap is juxtaposed to the bottom wall of the base, an entire first side of the intermediate portion, and the top wall of the lid.
In accordance with yet another embodiment of the invention, there is provided an instrument cassette. The cassette includes a base having an upright sidewall and a horizontal bottom wall, the upright sidewall having a lower slot and an upper aperture defined therein. The cassette further includes a latch member having a lower section, an intermediate section and an upper section, wherein (1) the lower section extends through the slot defined in the base, (2) the intermediate section is substantially planar, and (3) the upper section (i) extends through the upper aperture defined in the base, and (ii) has a slot defined therein. The cassette additionally includes a lid having a horizontal top wall and a tongue member attached thereto, wherein the tongue member extends through the slot defined in the upper section of the latch member when the lid is latched to the base.
Pursuant to still another embodiment of the invention, there is provided an instrument cassette. The cassette includes a base having a bottom wall and an upright sidewall, and a lid having a tongue member. The assembly further includes a latch member having (i) a lower section fixed in position relative to the base, (ii) an intermediate section, and (iii) an upper section which cooperates with the tongue member of the lid to latch the lid to the base, wherein the intermediate portion of the latch member is movable between a latch position and a release position, wherein one side of the intermediate section of the latch member is juxtaposed to the upright sidewall of the base when the intermediate section is located in the release position, and wherein the one side of the intermediate portion of the latch member is spaced apart from the upright sidewall of the base when the intermediate section is located in the latch position.
It is therefore an object of this invention to provide a new and useful instrument cassette assembly.
It is a further object of this invention to provide an improved instrument cassette assembly.
It is further an object of this invention to provide a new and useful instrument cassette.
It is further an object of this invention to provide an improved instrument cassette.
It is further an object of this invention to provide a new and useful method of protecting an instrument cassette.
It is further an object of this invention to provide an improved method of protecting an instrument cassette.
It is a further object of this invention to provide an instrument cassette that is configured to eliminate projecting components which could readily tear the sterile wrap used to envelop the cassette.
It is a further object of this invention to provide an instrument cassette which is easily manufactured and has a latch which uses only a single moving component.
The above and other objects, features, and advantages of the present invention will become apparent from the following description and the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an instrument cassette which incorporates the features of the present invention therein;
FIG. 2 is a side elevational view of the latch member of the instrument cassette of FIG. 1;
FIG. 3 is a top elevational view of the latch member of the instrument cassette of FIG. 1;
FIG. 4 is a fragmentary perspective view of the base of the instrument cassette of FIG. 1;
FIG. 5 is a fragmentary perspective view showing the relationship between the base of FIG. 4 and the latch member of FIG. 2;
FIG. 6 is a top elevational view of the base of the instrument cassette of FIG. 1;
FIG. 7 is a fragmentary cross sectional view of the instrument cassette of FIG. 1 enveloped in a sterile wrap;
FIG. 8 is a fragmentary perspective view of the lid of the instrument cassette of FIG. 1;
FIGS. 9-11 are fragmentary cross sectional views of the instrument cassette showing successive steps during the process of latching the lid to the base.
FIG. 12 is a fragmentary cross sectional view of the instrument cassette showing the latch member positioned in the release position.
DETAILED DESCRIPTION OF THE INVENTION
While the invention is susceptible to various modifications and alternative forms, a specific embodiment thereof has been demonstrated by way of example in the drawings and will herein be described in detail. It should be understood that there is no intent to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
Referring now to FIG. 1, there is shown an instrument cassette 10. The cassette 10 is used to hold medical or dental instruments and permits cleaning, sterilization, and storage of such instruments while housed in the cassette 10.
The instrument cassette 10 includes a lid 12 and a base 24. The lid 12 includes a top wall 22. A plurality of side walls 14, 16, 18, and 20 are attached in substantially perpendicular fashion to the periphery of the top wall 22. Collectively, the side walls 14, 16, 18, and 20 cooperate with the top wall 22 to provide a tray-like structure as shown in FIG. 1.
Similarly, the base 24 includes a bottom wall 34. A plurality of side walls 26, 28, 30, and 32 are attached in substantially perpendicular fashion to the periphery of the bottom wall 34. Collectively, the side walls 26, 28, 30, and 32 cooperate with the bottom wall 34 to provide a tray-like structure as shown in FIG. 1.
A plurality of holes 36 are defined in each of the top wall 22, the bottom wall 34, the side wall 28, and the side wall 32. The holes 36 are provided in a number of different sizes. It should be appreciated that the holes 36 could be added to, or deleted from, any of the walls of the lid 12 or the base 24 to meet the needs of a particular instrument cassette 10.
A pair of hinge members 48 is disposed on the side wall 18 of the lid 12. The hinge members 48 are received into a pair of hinge slots 50 defined in the side wall 32. The hinge members 48 cooperate with the hinge slots 50 to allow the lid 12 to pivot relative to the base 24. The hinge members 48 are shown integrated into the side wall 18, but it should be appreciated that the hinge members 48 could be separate components mechanically fastened to the side wall 18.
A pair of instrument racks 38 are disposed perpendicular to the bottom wall 34. The instrument racks 38 hold medical or dental instruments (not shown) during the cleaning and sterilization process, and the subsequent storage period until the instruments are next used.
The instrument cassette 10 includes a latch assembly 39. The latch assembly 39 includes a latch member 42 which is shown in more detail in FIGS. 2 and 3. A slot 44 is defined in the latch member 42 and cooperates with a tongue 46 of the lid 12. When the tongue 46 is received in the slot 44, the lid 12 is latched to the base 24, thereby securing the instruments within the cassette 10.
The components of the cassette 10 are made from stainless steel, or similar material. For example, the latch member 42 may be made from half-hard grade stainless steel 302. Also, the lid 12 and base 24 may be made from stainless steel 304.
A shown in FIGS. 2 and 3, the latch member 42 includes a latch section 42a, a latch section 42b, and a latch section 42c. The latch section 42c and the latch section 42b form an angle which is approximately 96°. Moreover, the latch section 42a and the latch section 42b form an angle which is approximately 130°. The slot 44 is provided in the latch section 42a in order to receive the tongue 46 (see FIG. 1) of the lid 12. A pair of holes 45 is defined in the latch section 42c. The holes 45 receive rivets to secure the latch member 42 to the bottom wall 34 of the base 24.
The latch member 42 is constructed from a single piece of material. The latch member 42 requires only two bends, a slot, and two holes, and thus is relatively simple and inexpensive to manufacture.
FIG. 4 is a fragmentary perspective view of the base 24 of the cassette 10. The base 24 includes the side wall 28 which has an aperture 40 defined therein. Disposed on each end of the aperture 40 is a flange 41. The side wall 28 includes a slot 29 defined therein which is located below the aperture 40. After assembly of the cassette 10, the latch member 42 extends through the slot 29 as shown in FIGS. 5, 9-12.
FIG. 5 is a fragmentary perspective view which shows the relationship between the base 24 and the latch member 42. FIG. 6 is a top elevational view of the base 24 of the cassette 10. The latch section 42c is disposed on the bottom wall 34 having been received through the slot 29. The latch section 42c is fastened to the bottom wall 34 with rivets 47. The rivets 47 are located with adequate clearance from the side 28 and the latch section 42a such that they are easily accessible with a drill for the purpose of removing the rivets 47 and replacing the latch member 42 should the need arise.
Referring again to FIG. 5, the latch section 42a extends through the aperture 40. The latch section 42a is resiliently biased against the flanges 41 in the direction as indicated by arrow 51 as shown in FIG. 5. Moreover, the side wall 28 prevents damage to the latch member 42 by preventing the latch member from being over extended in the direction indicated by arrow 53. In particular, as the latch member is being moved in the direction of arrow 53, the sidewall 28 functions as a stop to prevent further movement of the latch member at a predetermined point in its path of travel.
FIG. 7 is a fragmentary cross sectional view of the cassette 10 shown wrapped in a sterile wrap 33. The cassette 10 is maintained in this wrapped condition during sterilization of the cassette 10 and further during storage of the cassette until the instruments contained therein are needed for the next medical or dental procedure. During this storage period, the wrapped cassette 10 may be subjected to external forces which are generally normal to the storage of any item. For example, when the wrapped cassette 10 is stored on a shelve of a shelving unit, objects may bump the wrapped cassette. In addition, the wrapped cassette may be handled whereby the fingers of a nurse or doctor may grasp the wrapped cassette thus applying external forces to the sterile wrap 33 in the direction of the cassette 10. These types of external forces have a tendency to cause the sterile wrap 33 to tear or rip thus negatively affecting the sterile condition of the instruments contained in the wrapped cassette 10.
It is important to note that the configuration defined by the latch member 42, the base 24 and the lid 12 has substantial advantages in maintaining the integrity of the sterile wrap 33 which envelopes the cassette 10. In particular, when the lid 12 is locked to the base 24, the latch section 42b provides a planar surface against which the sterile wrap 33 abuts (see Location L1 ). At a location L2, the sterile wrap 33 transitions from the bottom wall 34 of base 24 to a lower end of the latch section 42b without encountering abrupt edges. Moreover, at a location L3, the sterile wrap transitions from an upper end of latch section 42b to the top wall 22 of lid 12 additionally without encountering abrupt edges.
Thus, the configuration defined by the latch member 42, the base 24 and the lid 12 reduces the likelihood that the sterile wrap 33 would be torn during storage and handling of the wrapped cassette.
Referring now to FIG. 8, a fragmentary perspective view of the lid 12 is shown. The lid 12 includes the side wall 14 which is affixed in a substantially perpendicular fashion to the top wall 22.
Disposed on the side wall 14 is the tongue 46. The tongue 46 is shown integrated into the side wall 14, but it should be appreciated that the tongue 46 could be a separate component mechanically fastened to the side wall 14.
The tongue 46 includes a tongue section 46a and a tongue section 46b. The tongue section 46a extends directly from the side wall 14 in a downward direction as shown in FIGS. 9-12. The tongue section 46b extends from the tongue section 46a in an inward direction towards the center of the cassette 10 (see also FIGS. 9-12).
FIGS. 9-11 show the instrument cassette 10 during the sequential steps of the latching process. In particular, the tongue section 46b is moved downward and into contact with the latch section 42a. Once in contact with the tongue section 42a, further downward forces are applied to the tongue section 46b. When these downward forces of the tongue section 46b become greater than the biasing forces inherent in the latch member 42, the latch section 42a is moved inwardly. As the latch section 42a is moved inwardly, the angled surface thereof directs the slot 44 toward the tongue section 46b. As the tongue section 46b is continued to be forced downwardly, the tongue section 46b is advanced into the slot 44 and the latch member 42 springs back to a latch position to complete the latching process as shown in FIG. 11. This effectively latches the lid 12 to the base 24.
The length of the tongue section 46b is designed to reduce the distance the tongue section 46b intrudes into the interior of the cassette 10. This allows for more usable space within the instrument cassette 10.
In order for the lid 12 to be unlatched from the base 24, the latch section 42b is pushed inwardly to a release position as shown in FIG. 12. As the latch member 42 is being advanced to the release position, the tongue section 46b is allowed to be raised upwardly through the slot 44. The lid 12 can then be lifted away from the base 24, thereby allowing access to the instruments within the cassette 10.
Once the tongue section 46b has been removed from the slot 44, the latch member 42 returns to its original position as shown in FIG. 9. No other manipulations need be performed on the latch member 42 prior to reinitiating the latching steps. This feature removes some extra steps often associated with other types of latches and thereby simplifies the use of the cassette 10. By contrast, the catch in a draw latch must be slid back to its initial position after each use.
As described in the aforementioned steps of the latching process, the latch member 42 is the only moving component of the latch assembly 39. This not only simplifies the design, but also increases the reliability of the cassette 10. In addition, as described above in reference to FIG. 6, should the latch member 42 wear beyond usefulness, it can easily be replaced.
While the invention has been illustrated and described in detail in the drawings and foregoing description, such an illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. For example, while the latch section 42c of the latch member 42 is shown attached to the bottom wall 34 of the base 24, it is also contemplated that the latch member 42 may be alternatively configured such that the latch section 42c is attached to the sidewall 28 of the base 24 instead of the bottom wall 34 of the base 24. | An instrument cassette and sterile wrap assembly includes a base having an upright sidewall and a horizontal bottom wall, the upright sidewall having a lower slot and an upper aperture defined therein. The assembly includes a latch member having a lower section, an intermediate section and an upper section, wherein (1) the lower section extends through the slot defined in the base, (2) the intermediate section is substantially planar, and (3) the upper section (i) extends through the upper aperture defined in the base, and (ii) has a slot defined therein. The assembly further includes a lid having a horizontal top wall and a tongue member attached thereto, wherein the tongue member extends through the slot defined in the upper section of the latch member when the lid is latched to the base. Moreover, the assembly includes a sterile wrap which envelops the base, the latch member and the lid, wherein the sterile wrap is juxtaposed to the bottom wall of the base, an entire first side of the intermediate portion of the latch member, and the top wall of the lid. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present invention claims priority from U.S. Provisional Patent Application No. 61/039,942, filed Mar. 27, 2008, and Canadian Patent Application No. 2,629,035, filed Apr. 11, 2008, which are incorporated herein by reference.
TECHNICAL FIELD
[0002] This invention relates to waveguide filters. More particularly, this invention relates to substrate integrated waveguide bandpass filters.
BACKGROUND OF THE INVENTION
[0003] An electrical bandpass filter is a fundamental element used for selecting an electrical signal in a frequency passband while suppressing electrical signals in a frequency stopband of the filter. Microwave and millimeter-wave bandpass filters are often used in modern radio-frequency transceivers. Filters having low in-band insertion loss, high spectral selectivity, and a wide stopband are commonly required. As an example, in a typical ground terminal for communication with satellites in the K a frequency band, a filter is required to suppress signals at transmission frequencies in a 29.5 GHz-30 GHz frequency range while conveying the signals at reception frequencies in a 19.2 GHz-21.2 GHz frequency range. An insertion loss of less than 1 dB and a stopband suppression level of at least 45 dB are desired to select the signal while avoiding self-jamming effects during simultaneous reception and transmission of electromagnetic signals by the ground terminal.
[0004] Microwave bandpass filters can be implemented as bulk waveguide structures. These are relatively heavy, bulky, and expensive; due to their size and weight, integration of bulk waveguide filters with planar components and electronic circuits can be a challenging task.
[0005] Substrate integrated waveguides (SIWs) are waveguide structures formed in a substrate of an electronic circuit. SIWs allow easy integration of planar circuits on a single substrate using a standard printed circuit board (PCB) or low-temperature co-fired ceramic (LTCC) process, or any other process of planar circuit fabrication. By using SIWs in an electronic circuit, the interconnection loss between components can be reduced. The size and the weight of the entire circuit can also be reduced.
[0006] SIW filters are known in the art. They offer a low-cost, low mass and compact size alternative to conventional waveguide filters, while maintaining high performance. Although various techniques have been implemented to improve the stopband performance of conventional rectangular waveguide filters, these techniques often utilize E-plane discontinuities that are difficult to realize for SIW filters implemented on a single-layer substrate. The SIW filters of the prior art have often been limited to resonant structures based on physical coupling elements to achieve a pre-selected spectral shape of the filter response function and/or high levels of stopband suppression. For example, a SIW filter designed to block an electromagnetic signal at a frequency f 0 has a slit in the top or bottom conducting layer to provide an attenuation pole at the frequency f 0 .
[0007] Transmission zeros (TZs) in the insertion loss response of a microwave filter can be used to improve the spectral selectivity and the stopband attenuation of the filter. To generate the TZs, an “extracted pole” technique can be implemented to construct so called “bandstop” resonators. Alternatively, electrical couplings can be introduced between non-adjacent resonators, wherein the TZs are generated due to a phenomenon of multipath interference of electromagnetic waves propagating inside the resonators. However, such filters are usually constructed using conventional waveguide technology, which tends to use bulky and complex filter structures. Furthermore, the TZs implemented using these prior-art methods cannot be far away from the desired passband due to the limitation of the physical structure of a prior-art waveguide filter.
[0008] The present invention overcomes the above stated problems of the prior art. It provides a low-cost, high-performance SIW filter that is easy to integrate with planar circuits. Advantageously, the spectral shape of the SIW filter of the present invention can be adapted to provide a high level of attenuation away from a desired passband. Furthermore, SIW filters can offer a significant improvement in passive intermodulation performance over conventional filters.
SUMMARY OF THE INVENTION
[0009] According to the present invention, a substrate integrated waveguide (SIW) filter includes a chain of sequentially coupled conterminous multimode SIW cavities, of which the first and the last multimode SIW cavities can be directly excited by a transmission line. The entire filter is implemented using arrays of metalized via holes on a dielectric substrate. The via holes are produced by using a standard printed circuit board (PCB) or other planar circuit manufacturing process. The diameter of the via holes and the pitch between neighboring via holes are selected so as to suppress radiation losses in the SIW cavities. A desired passband is generated by the fundamental mode of propagation in the SIW cavities. The finite transmission zeros (TZs) are generated by destructive interference between the fundamental and a higher-order electromagnetic mode of the SIW cavities. The size and the shape of the SIW cavities are selected so that the TZs are far away from the passband, for high out-of-band rejection. The position of every finite TZ is independently controllable. The freedom of positioning the TZs is achieved by changing the inter-cavity coupling ratios and the size of corresponding multimode SIW cavities. According to the present invention, no other mode discriminating physical structures within the SIW cavities, such as openings in a conductive layer of the PCB, are required to control the position of the TZs.
[0010] In accordance with the invention there is provided a filter having a passband and a stopband, for conveying passband frequency components of an electromagnetic signal, while suppressing stopband frequency components of the electromagnetic signal, the filter comprising:
an SIW formed in a planar dielectric layer sandwiched between first and second opposing planar conductive layers, the SIW having a chain of sequentially coupled conterminous multimode SIW cavities defined on their perimeters by an array of conductive vias connecting the first and the second conductive layers through the dielectric layer, the chain having first and second ends; an input transmission line coupled to the first end of the chain, for coupling the electromagnetic signal to the first end of the chain; and an output transmission line coupled to the second end of the chain, for outputting the passband frequency components of the electromagnetic signal from the second end of the chain; wherein a distance between neighboring vias of the array of conductive vias is small enough to suppress radiation losses of the SIW, for example less than half of a shortest wavelength of the electromagnetic signal in the SIW cavities.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Exemplary embodiments will now be described in conjunction with the drawings in which:
[0016] FIG. 1 is a three-dimensional view of a single-cavity substrate integrated waveguide (SIW) filter having opposing input and output microstrip transmission lines;
[0017] FIG. 2 is a three-dimensional view of a single-cavity SIW filter having input and output microstrip transmission lines disposed at 90° with respect to each other;
[0018] FIG. 3 is an equivalent circuit model for the mode coupling in the SIW cavities of FIGS. 1 and 2 ;
[0019] FIGS. 4A and 4B are magnetic field distributions of the fundamental mode and a higher-order mode, respectively, of the SIW filter of FIG. 1 ;
[0020] FIG. 5 is an insertion loss spectral plot for the SIW filter of FIG. 1 , superimposed with electric field distribution patterns in the SIW cavity corresponding to a first transmission maximum, a first transmission zero (TZ), and a second transmission maximum;
[0021] FIGS. 6 , 7 , and 8 are three-dimensional views of SIW filters of the present invention, having four sequentially coupled conterminous multimode SIW cavities;
[0022] FIGS. 9A and 9B are electric field distribution patterns in a four-cavity SIW filter at a fundamental passband and a spurious passband frequency of a signal, respectively;
[0023] FIGS. 10 to 12 are spectral plots of transmission and reflection of the SIW filters of FIGS. 6 to 8 , respectively;
[0024] FIGS. 13 to 15 are plan views of SIW filters of FIGS. 6 to 8 , respectively, showing dimension notations of the filters;
[0025] FIG. 16 is a comparative spectral plot of simulated and measured insertion loss of a SIW filter of FIG. 7 ; and
[0026] FIG. 17 is a comparative spectral plot of simulated and measured insertion loss of a SIW filter of FIG. 8 .
DETAILED DESCRIPTION OF THE INVENTION
[0027] While the present teachings are described in conjunction with various embodiments and examples, it is not intended that the present teachings be limited to such embodiments. On the contrary, the present teachings encompass various alternatives, modifications and equivalents, as will be appreciated by those of skill in the art. In FIGS. 6 , 7 , 8 , 9 A, and 9 B, like numerals refer to like elements.
[0028] A waveguide filter of the present invention uses at least two electromagnetic modes, propagating or evanescent. A passband of the filter is defined by a frequency range at which only the fundamental mode appears at an output port of the filter. A stopband of the filter is defined by all frequencies outside of the passband. Within the stopband, higher-order modes may create spurious passbands. By carefully selecting the dimensions of the substrate integrated waveguide (SIW) cavity, one transmission zero (TZ) or multiple TZs can be generated at specific locations in the stopband to suppress these spurious passbands.
[0029] In general, the insertion loss of a filter is proportional to the number of resonators n, inversely proportional to the unloaded quality factor Qu of the resonator, and also the relative bandwidth FBW of the filter. For a small-ripple, less than 0.1 dB, Chebyshev filter, the increase in insertion loss ΔS 21 at a center frequency ω 0 is given by
[0000]
Δ
S
21
(
dB
)
|
ω
-
ω
0
=
4.343
F
B
W
∑
i
=
1
n
g
i
Qu
i
(
1
)
[0030] wherein g i is a generalized low-pass prototype element (inductor or capacitor) value for an i th resonator.
[0031] The Qu of an SIW cavity is determined by three Q-factors, namely, the Q-factor related to lossy conducting walls Qc, the Q-factor related to dielectric loss D: Qd=1/tan(D), and the Q-factor related to energy leakage via gaps in the SIW cavity Qr. The unloaded quality factor is then expressed as
[0000] 1 /Qu =1 /Qc +1 /Qd +1 /Qr (2)
[0032] As is known in the art, by properly selecting the SIW substrate materials and the shape of the filter, the radiation loss represented by 1/Qr can be made much smaller than the dielectric and conductive losses represented respectively by 1/Qd or 1/Qc. At K a -band, the SIW cavity based on a conventional microwave dielectric substrate with a height of 20 mil and a dielectric loss tangent tan(D) of 0.0012 has a Qu of about 350, which is a typical quality factor of finline waveguide resonators. Therefore, a small number of SIW cavities, preferably four cavities, are used in a filter of the present invention to minimize insertion loss. The spectral selectivity of a filter of the present invention is improved by selecting SIW cavities of certain size and shape as will now be described.
[0033] Referring to FIG. 1 , a single-cavity SIW filter 10 is presented having a dielectric layer 11 sandwiched between a top planar conductive layer 12 and a bottom planar conductive layer 13 . A SIW cavity 19 of the filter 10 is defined on the perimeter of the cavity 19 by an array of conductive vias 14 connecting the top and the bottom conductive layers 12 and 13 through the dielectric layer 11 . The SIW cavity 19 is directly excited by one of symmetrical 50Ω microstrip lines 15 or 16 . Due to the symmetry of the SIW cavity 19 , it supports only TE n0m modes of propagation, wherein m is a positive number and n is an odd positive number. Preferably, the SIW cavity 19 is shaped and sized so as to support only two modes of propagation of the intended signal, the TE 101 mode and the TE 301 mode. The SIW filter 10 can be manufactured at a low cost using a standard printed circuit board (PCB) manufacturing process, or a low-temperature co-fired ceramic (LTCC) manufacturing process.
[0034] Throughout the specification, multimode SIW cavities are called, interchangeably, “oversized” cavities. This means that the size of the cavities can support more than one mode of propagation of an incoming signal. The SIW cavity 19 is termed herein as “oversized TE 101 /TE 301 SIW cavity”.
[0035] The distance b between neighboring vias 14 is small enough to suppress radiation losses of the SIW cavity 19 . As a rule, the distance b should be less than one half of the shortest wavelength of the electromagnetic signal in the SIW cavity 19 . The distance b for the cavity 19 of FIG. 1 is 1 mm, and the diameter d of the vias 14 is 0.5 mm. The overall size of the SIW cavity 19 is approximately 4.5 mm×10.5 mm for the given passband frequency range and the selected dielectric layer material Rogers RT/Duroid™ 6002. A central frequency f 0 of the passband is related to effective width a eff and length l eff of the SIW cavity 19 as follows:
[0000]
f
0
=
c
0
2
ɛ
r
(
1
a
eff
)
2
+
(
1
l
eff
)
2
(
3
)
[0036] where c 0 is the speed of light in air, a eff =a−d 2 /0.95b, l eff =l−d 2 /0.95b, and where a and l are the geometrical width and length of the SIW cavity 19 , respectively.
[0037] Referring to FIG. 2 , a single-cavity SIW filter 20 has the same elements as the filter 10 of FIG. 1 , but the microstrip line 16 is at 90° w.r.t. the microstrip line 15 . An oversized cavity 29 of the filter 20 supports two modes of propagation of an electromagnetic signal, the TE 101 mode and the TE 201 mode. The SIW cavity 29 is termed herein as “oversized TE 101 /TE 201 SIW cavity”. The coupling between the input and the output microstrip lines 15 or 16 and the higher-order TE 201 mode can reverse when the relative position of the lines 15 and 16 changes from the same half of the SIW cavity 29 to the opposite half of the cavity 29 . This coupling, which reaches a maximum when the input and the output are at an angle of 90°, can be adjusted by changing the relative position of the input and the output microstrip lines 15 and 16 and the size of the SIW cavity 29 . Therefore, a finite TZ can be on the lower-frequency side or the higher-frequency side of the resonance of the higher-order TE 201 mode, and can be positioned slightly closer to the resonance of the fundamental TE 101 mode, to further improve the stopband performance of the filter 20 .
[0038] Turning now to FIG. 3 , an equivalent circuit model 30 for the mode coupling in the SIW cavities 19 and 29 of FIGS. 1 and 2 is illustrated. The model 30 shows, in a symbolic form, signal paths between a source port S and a load port L. The fundamental resonant mode TE 101 generates a transmission pole in the desired passband. A second-order resonant mode TE 301 provides a different path for the signal flow between the two ports S and L corresponding to microstrip lines 15 and 16 of the SIW filter 10 from a path corresponding to the fundamental resonant mode TE 101 . Similarly, a second-order resonant mode TE 201 provides a different path for the signal flow between the two ports S and L corresponding to microstrip lines 15 and 16 of the SIW filter 20 as compared to a path provided by the fundamental resonant mode TE 101 . Because all the couplings J 1 ′, J 2 ′, J 3 ′, and J 4 ′ in an oversized SIW cavity of the present invention have the same sign, and J 1 ′ and J 2 ′ are much larger than J 3 ′ and J 4 ′ close to the resonant frequency of the second-order mode TE 201 , or TE 301 , a TZ between the resonant frequency of the TE 101 mode and the resonant frequency of the TE 201 or TE 301 mode is generated. The location of the TZ can be approximately determined by using the following relationship:
[0000]
ω
z
′
≈
-
J
3
′
J
4
′
J
1
′
J
2
′
B
TE
201
/
TE
301
′
(
4
)
[0039] wherein ω′ z is the generalized angular frequency of the TZ, J 1 ′ and J 2 ′ are the generalized coupling admittances between the source port S and the load port L and TE 101 mode, and J 3 40 and J 4 ′ are the generalized coupling admittances between the source port S and the load port L and one of TE 201 or TE 301 modes, as is denoted in FIG. 3 . B′ TE201/TE301 is the generalized constant susceptance of one of the TE 201 or TE 301 modes. In general, the TZ is shifted in frequency relative to the transmission pole of the fundamental mode TE 101 because the product of J 1 ′ and J 2 ′ is much larger than the product of J 3 ′ and J 4 ′ close to the resonance frequency of the TE 201 or TE 301 mode. For the oversized SIW cavity 19 , the location of the TZ can be slightly tuned by changing the width of the SIW cavity 19 with little effect on the desired passband response generated by the TE 101 mode. The location of the TZ in the oversized SIW cavity 29 can be tuned by changing the relative position of the microstrip lines 15 and 16 , as noted above.
[0040] Turning now to FIGS. 4A and 4B , magnetic field distributions 40 A and 40 B of the fundamental mode TE 101 and the higher-order mode TE 301 are illustrated. The modes TE 101 and TE 301 are symmetrically excited in the SIW cavity 19 by the 50Ω microstrip line 15 . The mode couplings between the microstrip line 15 and the modes TE 101 and TE 301 are both positive, the coupling between the microstrip line 15 and the TE 101 mode being significantly stronger than the coupling between the microstrip line 15 and the TE 301 mode. Thus, a TZ above the resonance of the TE 101 mode is generated; this TZ is shifted far away from the resonance of the TE 101 mode because the coupling between the microstrip line 15 and the TE 101 mode is much stronger than the coupling between the microstrip line 15 and the TE 301 mode.
[0041] Referring to FIG. 5 , a simulated spectral plot 50 of the insertion loss of the single-cavity SIW filter 10 is shown, having superimposed thereupon electric field distributions in the SIW cavity 19 of the filter 10 corresponding to a first transmission maximum 54 , a first TZ 55 , and a second transmission maximum 56 . A pattern 51 denotes the electric field distribution at the resonance point 54 in the SIW cavity 19 of the filter 10 excited by the input microstrip line 15 . The pattern 51 corresponds to an electric field distribution of a transmission pole, when the TE 101 mode is in resonance. Similarly, patterns 52 and 53 denote the electric field distribution at the TZ 55 and at the transmission pole 56 , respectively. At the point 55 , the TE 301 mode is close to being in resonance, at which point it is of a sufficient strength to cancel the off-resonance mode TE 101 at the output microstrip line 16 . One can see that the TZ 55 is generated at about 30 GHz, while the point of maximum transmission 54 is at 20 GHz. Advantageously, such a large distance between the TZ 55 and the transmission pole 54 is generated without resorting to placing any discriminating physical structures inside the cavity 10 , such as openings in the top conductive layer 12 or the bottom conductive layer 13 of the SIW cavity 10 .
[0042] Referring now to FIG. 6 , a three-dimensional view of an SIW filter 60 of the present invention is shown. Similar to the single-cavity SIW filter 10 of FIG. 1 , the SIW filter 60 of FIG. 6 has a dielectric layer 61 sandwiched between top and bottom opposing planar conductive layers 62 and 63 , respectively. An array of the conductive vias 14 connects the conductive layers 62 and 63 through the dielectric layer 61 thereby forming a chain of four sequentially coupled conterminous multimode SIW cavities 69 1 to 69 4 defined on their perimeters by an array of the vias 14 as shown. The neighboring cavities 69 1 and 69 2 ; 69 2 and 69 3 ; and 69 3 and 69 4 are coupled to each other by a via-free opening 101 in a common wall therebetween. The SIW cavity 69 1 is directly excited by an input signal coupled to a transmission line 65 , and a transmission line 66 is used to output the signal. The lines 65 and 66 are preferably microstrips, however striplines or coplanar waveguides can also be used. Inside the outer SIW cavities 69 1 and 69 4 , the lines 65 and 66 are defined by non-conductive slots 67 and 68 , respectively. The slots 67 and 68 have ends perpendicular to the lines 65 and 66 , which facilitates improvement of the stopband performance without deteriorating the passband performance of the filter 60 . Preferably, the slots 67 and 68 and the microstrips 65 and 66 are formed by patterning the top conductive layer 62 . The electromagnetic signal is coupled into the first SIW cavity 69 1 by the line 65 having slots 67 , and then is coupled into the next cavities 69 2 ; 69 3 ; and 69 4 by the via-free openings, or “post-wall irises” 101 as shown in FIG. 6 . The via-free openings are defined by eight conductive vias 14 common to perimeters of neighboring SIW cavities. At least two vias can be used for this purpose. The line 66 is used to output the electromagnetic signal from the last cavity 69 4 of the filter 60 .
[0043] According to the present invention, the size and the shape of the SIW cavities 69 1 to 69 4 of the filter 60 are selected to support at least two modes of propagation for passband frequency components and for stopband frequency components of the electromagnetic signal. At least two modes of each stopband frequency component cancel each other at TZs upon propagating through the chain of the SIW cavities 69 1 to 69 4 , thereby suppressing the stopband frequency components. Preferably, the output transmission line 66 is positioned at one of these TZs, so that the two modes of each stopband frequency component cancel each other upon propagating through the filter 60 . The output transmission line 66 may be disposed co-planar with the top conductive layer 62 , as is shown in FIG. 6 , or, alternatively, it may be co-planar with the bottom conductive layer 63 .
[0044] The position of the TZs is dependent on the position of the input transmission line 65 and the shape of the SIW cavities 69 1 to 69 4 . A specific example of dimensions of the filter 60 suitable for K a -band performance will be given below. Spatial distributions of the electric field in a filter having similar geometry as the filter 60 are shown in FIGS. 9A and 9B , to be discussed later.
[0045] The stopband frequency components are suppressed at the prescribed finite TZs produced by corresponding oversized SIW cavities. Preferably, each SIW cavity 69 1 to 69 4 is of such shape and size that the two modes of at least a fraction of the stopband frequency components cancel each other upon propagating through a corresponding SIW cavity. Shifting the frequencies of TZs of the SIW cavities 69 1 to 69 4 relative to each other results in broadening of the stopband of the filter 60 , while still attaining high levels of attenuation in the stopband.
[0046] Turning to FIGS. 7 and 8 , three-dimensional views of SIW filter 70 and 80 of the present invention are shown, respectively. The SIW filter 70 has SIW cavities 79 1 to 79 4 , and the SIW filter 80 has SIW cavities 89 1 to 89 4 . What is different between the SIW filters 60 , 70 , and 80 of FIGS. 6 , 7 , and 8 , is the position of the input microstrip lines 65 and the output microstrip lines 66 relative to a longitudinal axis 102 . Specifically, in the SIW filter 60 , the microstrip lines 65 and 66 are parallel to the axis 102 ; in the SIW filter 70 , the microstrip line 65 is parallel to the axis 102 while the microstrip line 66 is perpendicular to the axis 102 ; and in the SIW filter 80 , both microstrip lines 65 and 66 are perpendicular to the axis 102 . Accordingly, the SIW cavities 69 1 to 69 4 ; 79 1 to 79 3 ; and 89 2 and 89 3 are oversized TE 101 /TE 301 SIW cavities; and the SIW cavities 79 4 , 89 1 , and 89 4 are oversized TE 101 /TE 201 SIW cavities. Varying orientations of the microstrip lines 65 and 66 allow fine tuning of the TZ frequencies of a first and a last SIW cavity in a chain of consecutively coupled SIW cavities, in a similar manner to tuning the TZ frequencies of the SIW cavity 29 of FIG. 2 .
[0047] Referring now to FIGS. 9A and 9B , simulated electric field distribution patterns 91 A and 91 B in the SIW cavities 99 1 to 69 4 of the filter 90 are shown. The filter 90 has the same general geometry as the filter 60 of FIG. 6 , having input and output microstrip lines 95 and 96 , respectively, and TE 101 /TE 301 SIW cavities 99 1 to 99 4 . The patterns 91 A and 91 B correspond to electromagnetic signals at a fundamental passband frequency and a spurious passband frequency, respectively. The resonant mode of the fundamental passband is the TE 101 mode, while the resonant mode of the spurious passband is the TE 301 mode.
[0048] Turning now to FIGS. 10 to 12 , simulated transmission and reflection response characteristics of the SIW filters 60 , 70 , and 80 of FIGS. 6 , 7 , and 8 are shown, respectively. The filters 60 , 70 , and 80 are exemplary embodiments of a K a -band filter. In a K a -band satellite communications ground terminal, the transmission occurs at 29.5 to 30 GHz, while the reception occurs within 19.2-21.2 GHz. A receiving filter is normally used for suppressing a 29.5-30 GHz transmission signal to prevent self-jamming, while conveying a 19.2-21.2 GHz signal to be received by a receiver. One can see that the stopband rejection over the satellite transmit frequency band of 29.5-30 GHz, seen in FIG. 10 , is close to 45 dB. Furthermore, in FIGS. 11 and 12 , the stopband rejection of the filters 70 and 80 over the satellite transmit frequency band of 29.5-30 GHz is better than 50 dB, although only four multimode SIW cavities are used to arrive at a low insertion loss of 0.5-0.7 dB. An alternative way of defining the performance of the filters 60 , 70 , and 80 as seen from FIGS. 10 to 12 , is to define a 3 dB passband and a 35 dB stopband. The 3 dB bandwidth of the passband in FIGS. 10 to 12 is at least 10% of a center frequency f P =20.2 GHz of the passband, that is, a middle frequency of the 3-dB points defining the passband. The 35 dB bandwidth of the stopband is at least 2% of a center frequency f S =29.75 GHz of the stopband, that is, a middle frequency of the 35-dB points defining the stopband. This performance is achieved at the stopband located away from the passband, so that f S -f P >0.3* f P .
[0049] Referring to FIGS. 13 to 15 , plan views of SIW filters of the present invention are presented. The views of FIGS. 13 , 14 , and 15 show notations of the main dimensions of the filters 60 , 70 , and 80 , respectively. Tables 1 to 3 below show example dimensions of the corresponding K a -band filters, in accordance with the notations of FIGS. 13 to 15 .
[0000]
TABLE 1
for FILTER 60
w io
3.22 mm
l 1
4.46 mm
w 12
3.19 mm
l 2
4.54 mm
w 23
2.99 mm
a SIW
10.5 mm
w ms
1.28 mm
w SLO
2.56 mm
[0000]
TABLE 2
for FILTER 70
w ms
1.28 mm
w 12
3.19 mm
w io
3.22 mm
w 23
2.99 mm
w i
2.56 mm
w 34
3.24 mm
l i
1.48 mm
a 1
10.66 mm
l 1
4.46 mm
a 2
6.60 mm
l 2
4.54 mm
w o
3.14 mm
l 3
4.53 mm
l o
1.6 mm
l 4
5.35 mm
[0000]
TABLE 3
for FILTER 80
w ms
1.28 mm
w 23
2.99 mm
w io
3.08 mm
w 34
3.24 mm
w i
2.88 mm
a 1
6.6 mm
l i
1.50 mm
a 2
10.75 mm
l 1
5.43 mm
a 4
6.6 mm
l 2
4.47 mm
w o
3.14 mm
l 3
4.52 mm
l o
1.6 mm
l 4
5.35 mm
o 1
3.14 mm
w 12
3.46 mm
o 4
2.11 mm
[0050] A skilled artisan will realize that the filter shapes and sizes, defined by the sets of dimensions tabulated in Tables 1 to 3, are not the only possible shapes and sizes of a K a -band filter of the present invention. Furthermore, for another passband and stopband frequency and attenuation level specification, as well as for another dielectric layer material, the dimensions can be different. It is to be understood, however, that the invention encompasses various sizes and shapes of SIW cavities that support two modes, so that the two modes cancel each other upon propagating through the sequential chain of the SIW cavities, thereby suppressing the stopband frequency components at defined TZ locations. As is appreciated by one skilled in the art, the above described “mode cancelling” function will determine the shape and size of SIW cavities. In particular, one can observe from the Tables 1 to 3 that individual SIW TE 101 /TE 301 cavities are more than twice as wide as they are long. One can also observe that the individual SIW cavities are more than three times as wide as the width of the corresponding via-free openings. As for the size of the SIW cavities, for a K a -band application, the TE 101 /TE 301 cavities are preferably 8 mm to 14 mm wide, the TE 101 /TE 201 cavities are between 5 mm to 8 mm wide, with the total length of the entire chain of four cavities being in the range of 16 mm to 22 mm. The size of the cavities may vary and depends on the dielectric constant of the substrate material used.
[0051] The filters 60 , 70 , and 80 are preferably manufactured in a PCB having linear arrays of metalized via holes with a diameter of 0.5 mm and a center-to-center pitch of 1 mm, although other pitch dimensions that are fine enough to prevent radiation losses may be used. For the PCB, a 20 mil thick RT/Duroid™ 6002 or 20 mil thick RT/Duroid 5880 PCB material may be used. Both materials are supplied by Rogers Corp., having headquarters in Rogers, Conn., USA. In theory, the unloaded quality factor Qu of an SIW resonator based on 20 mil thick Rogers RT/Duroid 5880 is about 500, while the Qu of an SIW resonator based on 20 mil thick Rogers RT/Duroid 6002 is only about 350. Hence, the RT/Duroid 5880 substrate is expected to be beneficial from the insertion loss standpoint. In reference to Eq. (2) above, both Qd and Qc of an SIW cavity made of RT/Duroid 5880 are higher than Qd and Qc of an SIW cavity made of RT/Duroid 6002. The Qd is higher because of a lower loss tangent tan(D). The Qc is higher for the RT/Duroid 5880 because of larger cavity dimensions, due to a lower dielectric constant as compared to Rogers RT/Duroid 6002.
[0052] Both abovementioned Rogers substrates use a similar fabrication process and have a similar fabrication cost. However, RT/Duroid 6002 has better mechanical properties than RT/Duroid 5880. The RT/Duroid 6002 material is suitable for laser drilling, and via holes of a wide range of diameters can be drilled by this method. The RT/Duroid 5880 material must be mechanically drilled, and mechanical drilling generally has a lower degree of precision than laser drilling. The better suitability for machining of the RT/Duroid 6002 material makes it preferable over the RT/Duroid 5880 material, even though the 5880 material has a better electrical performance as explained above. The filters 60 , 70 , and 80 were designed and fabricated using 20 mil thick Rogers RT/Duroid 6002 material.
[0053] Turning now to FIG. 16 , spectral plots of simulated and measured insertion loss of the SIW filter 70 of FIG. 7 are presented. A variation of the dielectric constant of the substrate and a fabrication error led to a slight frequency shift of about 1.5% between the simulated and the measured responses. The measured minimum in-band insertion loss is approximately 0.9 dB, which is slightly higher than the simulated loss of 0.75 dB due to the additional loss of a 90° microstrip bend, not shown, and an additional section of microstrip line, not shown. There is a maximum variation of about 0.6 dB in the insertion loss across the passband. The attenuation in the frequency band of 25.3 GHz -31.7 GHz is better than 40 dB, while in the transmission (Tx) band of 29.5 GHz-30 GHz it is better than 58 dB. There is a spike around 31.7 GHz due to higher-order resonances of the TE 201 mode and TE 301 mode.
[0054] Referring now to FIG. 17 , spectral plots of simulated and measured insertion loss of the SIW filter 80 of FIG. 8 are presented. Similar to the spectral plot of FIG. 16 , a slight frequency shift of about 1.3% between the simulated and measured responses occurs due to the variation of the dielectric constant of the substrate, as well as due to fabrication tolerances. The measured minimum in-band insertion loss is around 0.8 dB, which is very close to the simulated loss of 0.77 dB. The attenuation in the frequency band of 23.94 GHz-31.48 GHz is better than 40 dB, while in the Tx band of 29.5 GHz-30 GHz it is better than 52 dB. There is a spike around 31.6 GHz due to the higher-order resonances of the TE 201 mode and TE 301 mode. | A waveguide bandpass filter for use in microwave and millimeter-wave satellite communications equipment is presented. The filter is based on a substrate integrated waveguide (SIW) having several cascaded oversized SIW cavities. The filter is implemented in a printed circuit board (PCB) or a ceramic substrate using arrays of standard metalized via holes to define the perimeters of the SIW cavities. Transmission lines of a microstrip line, a stripline or coplanar waveguide are used as input and output feeds. The transmission lines have coupling slots for improved stopband performance. The filter can be easily integrated with planar circuits for microwave and millimeter wave applications. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to laminated glassware and is primarily concerned with the manufacture of strong, lightweight glass articles comprising color decorations which are useful for tableware, for lighting, and for other applications utilizing decorated glass.
U.S. Pat. No. 3,673,049 to Giffen et al. discloses a laminated glass body comprising a tensilely stressed core portion and an adherent, compressively stressed surface layer substantially enveloping the core portion, made by a continuous hot-forming process. Such laminates are useful for the production of strong, lightweight dinnerware and the like, the compressive stresses therein rendering the laminates highly resistant to mechanical breakage.
The decoration of laminates such as described in the aforementioned Giffen et al. patent is presently accomplished by means conventional for dinnerware, e.g., through the use of ceramic decals or similar decorating media which permit the application of color designs to the outer surfaces of the laminates. Such conventional decorations are subject to mechanical and chemical attack in use; thus special glazing compositions and high temperature firing treatments are utilized to insure adequate service life.
Although integrally colored glasses have been used to provide decorative glass and ceramic ware of high durability, the use of colored glass is not a very flexible design technique, particularly where large quantities of ware having different designs are to be produced. For this purpose, design methods permitting the application of any one of a large number of different designs to a single product or a small number of related products are preferred.
Very recently, photosensitive glasses which can be treated in the solid state to impart integral coloration over an extremely wide range of colors have been discovered. Hence U.S. Pat. No. 4,017,318 to Pierson and Stookey discloses photosensitive glasses containing silver, alkali metal oxides, fluorine, at least one of chlorine, bromine and iodine, and, optionally, CeO 2 , which glasses can be treated utilizing a sequence of high energy radiation and heating steps to produce integral coloration therein. Thus multi-colored photographs and other decorative designs can be developed in these glasses with a great deal of design flexibility.
The production of strong, lightweight glass articles from photosensitive glasses such as described in the aforementioned patent is difficult. The colors developed in such glasses are modified by exposure to high temperatures, such that air tempering and other strengthening methods involving heating have only limited utility. Similarly, the development of color in such glass requires treatment at elevated temperatures such that tempered or otherwise strengthened ware cannot subsequently be decorated without loss of strength.
It is the principal object of the present invention to provide a strong, lightweight glass article comprising photosensitive glass which can be decorated without reducing the mechanical strength thereof.
It is a further object of the invention to provide a strong, lightweight glass article comprising integrally colored photosensitive glass.
Other objects and advantages of the invention will become apparent from the following detailed description thereof.
SUMMARY OF THE INVENTION
In accordance with the present invention there is provided an integrally colored, laminated glass article consisting of a tensilely stressed core layer composed of a spontaneous fluoride opal core glass and a compressively stressed surface layer fused to and substantially enveloping said core layer composed of a photosensitive surface layer glass. The surface layer glass includes at least one integrally colored region containing microcrystals of alkali metal fluoride together with a coloring metallic silver phase.
The core glass of the laminate of the invention is of alkali aluminosilicate composition, having an average linear coefficient of thermal expansion (0°-300° C.) of at least about 75 × 10 -7 /° C., and is essentially free of the alkali metal oxide Li 2 O. The average linear coefficient of thermal expansion of the surface layer glass (0°-300° C.) is at least about 10 × 10 -7 /° C. less than that of the core glass, and the thickness of the surface layer is at least about 0.002 inches. The ratio of the thickness of the core layer to the thickness of the surface layer is at least about 8:1.
The surface layer glass of the laminate contains at least about 0.01% silver by weight, and the integrally colored region of the surface layer contains microcrystals of alkali metal flouride in a concentration of at least about 0.005% by volume. This region further contains, as the coloring phase, discrete colloidal particles of metallic silver less than about 200A in the smallest dimension, and/or metallic silver contained within at least a portion of said alkali metal fluoride microcrystals, said silvercontaining portion of the microcrystals being less than about 200A in the smallest dimension, and/or a coating of metallic silver on at least a portion of the surface of the alkali metal fluoride microcrystals, the portion of the microcrystals coated with silver being less than about 200A in the smallest dimension.
The method of forming a laminated decorated glass article in accordance with the invention broadly comprises, first, providing a melt of an alkali aluminosilicate core glass and adjusting the viscosity of the melt to a value suitable for lamination. The core glass selected for melting must be essentially free of Li 2 O and possess the thermal expansion characteristics specified above.
A second melt of a photosensitive surface layer glass having a viscosity suitable for lamination is also provided, the glass selected for melting containing at least about 0.01% of silver by weight and having the thermal expansion characteristics hereinabove set forth. The first and second melts are then combined into laminated sheet consisting of a photosensitive surface layer and an alkali aluminosilicate core, and this sheet is then shaped to provide a laminated glass article wherein the surface layer is at least about 0.002 inches in thickness and the ratio of core thickness to surface layer thickness is at least about 8:1. The core spontaneously transforms to white opal glass as the shaped article is cooled after forming.
Finally, selected regions of the photosenstive surface layer are developed to provide integrally colored regions containing alkali metal fluoride crystals and metallic silver as hereinabove described. The colors of the regions selected for development are controlled in the known manner by varying the irradiation and heating treatments used in the development process.
A laminated glass article such as described exhibits high strength even in thin cross-section, and is thus mechanically durable. The surface layer glass demonstrates good photosensitivity such that strongly saturated colors may be developed therein by conventional color development techniques. The opal core, which is typically opaque and white in color, provides an excellent background for color decorations developed in the photosensitive surface layer, and the decorations so developed, being present within the bulk of the surface layer glass, are not subject to deterioration in use. Thus the problem of toxic metal release is avoided and a strong, durable, decorated glass article is provided.
DESCRIPTION OF THE DRAWING
The invention may be further understood by reference to the drawing wherein:
FIG. 1 consists of an enlarged diagrammatic elevational view in cross-section of a laminated glass article, i.e., a laminated plate, provided in accordance with the invention. The dimensions of the designated photosensitive surface layer glass and the designated opal core glass are not drawn to scale or shown in true proportion, but the relative positions of the core and surface layer in a typical article are illustrated.
FIG. 2 is a further enlarged partial diagrammatic elevational view in cross-section of a laminated article such as shown in FIG. 1, wherein the coloring phase giving rise to integral coloration in the developed photosensitive surface layer is schematically depicted as a multiplicity of discrete particles.
DETAILED DESCRIPTION
In selecting glass to be utilized for the core of the laminated article of the invention, it is important that the requirements of spontaneous opacity and a moderately high thermal expansion coefficient be observed. The so-called heat-treated opal glasses, i.e., glasses which do not develop opacity on forming from the melt but are instead heated subsequent to forming in order to develop opacity, are not good core materials for the present purpose because the temperatures required for developing a suitable level of opacity therein undesirably affect the color and/or photosensitivity of the surface layer glass.
Low thermal expansion in the core glass leads to laminated articles exhibiting low strength. Thus a core glass exhibiting an average linear coefficient of thermal expansion over the temperature range 0°-300° C. of at least about 75 × 10 -7 /° C. is required. Core glasses having expansions in the range of about 85-95 × 10 -7 /° C. provide the best combination of strength and laminate fracture characteristics when laminated to the photosensitive surface layer glasses hereinafter described.
It is also important that the core glass be essentially free of lithium oxide. Although Li 2 O is a desirable component in some spontaneous opal composition systems, we have found that lithium can migrate from the core glass into the photosensitive surface layer glass during formation of the laminate. This lithium then acts to substantially degrade the photosensitivity of the surface layer glass, such that the capability of the surface layer glass to develop intense colors upon subsequent treatment is considerably impaired.
Spontaneous opal core glasses exhibiting the properties necessary for use in the laminate may be selected from a rather wide range of alkali aluminosilicate composition. Preferably, however, the core glass is one having a composition comprising in weight percent as calculated from the batch, about 57-76% SiO 2 , 5-11% Al 2 O 3 , 5-17% Na 2 O, 0-3% K 2 O, and 4-10% F.
Examples of spontaneous opal glasses suitable for use as core glasses for the laminate are set forth in Table I below. Such glasses may be melted in accordance with normal glass-melting practice, being suitably compounded from batches composed of conventional glass batch constituents which are converted to the designated oxide or other glass constituents at the temperatures used for melting the batch. The molten glass thus provided may then be incorporated into a laminate by combining with photosensitive surface layer glass at viscosities in the range of about 400-4000 poises in accordance with known methods.
The compositions reported in Table I are reported in parts by weight on the oxide basis as calculated from the batch, except for fluorine which is reported in parts by weight on the elemental basis in the usual manner. Also reported in Table I are average linear coefficient of thermal expansion values for each of the glasses, as measured over the temperature range 0°-300° C.
TABLE I______________________________________ 1 2 3 4 5 6 7 8______________________________________SiO.sub.2 65.0 75.7 60.2 57 62 64.1 63.7 61Al.sub.2 O.sub.3 6.1 6.23 10.4 5.9 6.2 8.0 6.8 5.0Na.sub.2 O 5.0 16.37 8.45 11.6 12.6 9.9 12.5 14K.sub.2 O 1.9 1.25 2.15 1.0 -- -- 1.6 --F 6.1 4.57 4.3 7.8 8.0 7.3 9.7B.sub.2 O.sub.3 -- -- 1.4 2.4 11.4 -- -- --CaO 15.7 0.17 4.7 -- -- 8.1 10.8 14.3ZnO -- -- 9.8 --BaO -- -- -- 14.2 -- -- -- --P.sub.2 O.sub.5 -- -- -- 7.9 -- -- -- --ThermalExpansionCoefficient(×10.sup.-7 /° C) 80 94 83 88 101 98 98 104______________________________________
The importance of the hereinabove described limitations relating to core composition and thermal expansion is demonstrated by further composition examples given in Table IA below, also reported in parts by weight:
TABLE IA______________________________________ A B C______________________________________SiO.sub.2 72.8 58 65.2Al.sub.2 O.sub.3 3.6 18.4 7.9Na.sub.2 O 6.6 10.0 4.8K.sub.2 O 10.1 -- --Li.sub.2 O 2.1 -- --F 4.7 4.0 5.9B.sub.2 O.sub.3 -- 0.3ZnO -- 8.0 9.4CaO -- 0.9 6.5MgO -- 0.4 --______________________________________
The glasses in Table IA are not suitable for use in the laminate of the invention. Example A of Table IA is a spontaneous opal glass which is found to deleteriously affect the photosensitivity of surface layer glasses with which it is combined, due to the presence of Li 2 O therein. Example B is an opal glass which disadvantageously requires a heat treatment subsequent to forming, in order to develop sufficient opacity for use, while Example C is a spontaneous opal glass having an average linear coefficient of thermal expansion of about 59 × 10 -7 /° C., a value too low for use in the invention.
The composition of the photosensitive glass utilized to provide the surface layer of the laminate is also an important variable affecting the physical properties of the laminate and the decorating characteristics thereof. For reasons relating to the effects of lamination on photosensitivity and/or the relatively thin surface layer which is employed, many compositions which produce good coloration in bulk form do not perform adequately as the laminate surface layer.
The amount of silver present in the surface layer glass is a particularly important variable from the standpoint of color development. Hence, in addition to the essential photosensitizing constituents fluorine, the alkali metal oxides, and at least one of chlorine, bromine and iodine, the glass must contain at least about 0.01% Ag by weight in order to exhibit the degree of photosensitivity required.
The combined requirements of good photosensitivity and low thermal expansion dictate a preferred range of surface layer glass composition which includes glasses consisting essentially, in weight percent as calculated from the batch, of about 68-74% SiO 2 , 14-18% Na 2 O, 4-10% Al 2 O 3 , 3-9% ZnO, 1.8-6% F, 0.1-2.5% Br, 0.01-0.05% Ag, 0.01-0.10% CeO 2 , 0.05-3.0% Sb 2 O 3 , and 0.04-0.2% SnO. The presence of CeO 2 in these compositions is specified because ultraviolet radiation is the high energy radiation of choice for developing decorations in the surface layer of the laminate.
Glasses within the above-described composition range may be compounded utilizing conventional glass batch constituents, including oxides or other compounds which will be converted to the specified oxides or elements at the temperatures utilized for melting the batch, and may be melted in suitable melting units at ordinary temperatures. They may then be incorporated into laminated articles by combining at viscosities in the range of about 700-3000 poises with spontaneous opal core glasses as hereinabove described.
Examples of photosensitive glass compositions suitable for use in the invention are reported in Table II below. The compositions are reported in parts by weight on the oxide basis as calculated from the batch, except for silver and the halogens which are reported on an elemental basis in accordance with conventional practice. Also reported in Table II are average linear coefficients of thermal expansion over the temperature range 0°-300° C., where determined on individual samples.
TABLE II______________________________________ 9 10 11______________________________________SiO.sub.2 72.0 72.0 72.0Na.sub.2 O 16.2 16.2 16.2Al.sub.2 O.sub.3 6.9 6.9 6.8ZnO 5.0 5.0 5.0F 2.5 2.6 2.6Br 1.1 1.1 0.8Ag 0.01 0.02 0.03CeO.sub.2 0.05 0.10 0.10Sb.sub.2 O.sub.3 0.2 1.0 0.30SnO 0.05 0.08 0.20Expansion Coef-ficient(×10.sup.-7 /° C.) 83 83 83______________________________________
The importance of photosensitive glass composition on the properties of laminates comprising photosensitive glass surface layers is shown in part by the further composition examples set forth in Table IIA below:
TABLE IIA______________________________________ D E______________________________________SiO.sub.2 72.7 72.7Na.sub.2 O 18.3 18.5Al.sub.2 O.sub.3 6.8 6.8ZnO 5.0 5.0F 2.5 2.5Br 0.2 0.1Ag 0.0012 0.005CeO.sub.2 0.018 0.018Sb.sub.2 O.sub.3 0.2 0.1SnO -- 0.1______________________________________
The glasses in Table IIA are representative of photosensitive glasses which are not suitable for use in the invention. Glass D does not give good coloration utilizing conventional coloration techniques when employed as a surface layer glass in accordance with the invention, because it contains insufficient silver for that purpose. Glass E is low in silver and is also too high in thermal expansion to provide a strong laminate.
The fabrication of laminated articles in accordance with the invention may be accomplished utilizing procedures such as described, for example, in U.S. Pat. No. 3,673,049 to Giffen et al. Briefly, such procedures comprise compounding and melting glasses for the core and surface layer portions of the laminate, uniting the molten glasses at flowing viscosity to form a laminated intermediate, e.g., laminated sheet, and then shaping the soft laminated sheet into a glass article of a selected shape prior to cooling to room temperature. The absence of defects at the interface between the core and surface layer of the laminated article, and the compressive stresses which are generated in the surface layer of the article as it is cooled from the setting point of the softest glass in the laminate to room temperature, provide the high mechanical strength which is observed.
The decoration of a laminate produced as described simply involves processing in accordance with methods known for use with photosensitive glass. As noted in the aforementioned U.S. Pat. No. 4,017,318 to Pierson and Stookey, the development of color in photosensitive glasses such as used in the present laminates can be accomplished by a combination of high energy irradiation and heat treatment steps. A suitable color development process comprises first irradiating the glass with intense ultraviolet light in regions where color development is desired, and then heating the glass article at a temperature between the transformation range and softening point of the photosensitive glass for a time at least sufficient to cause nucleation and crystal growth within the glass. The initial irradiation step largely determines the ultimate color developed in the glass, which color is apparently a function of the total flux of ultraviolet light received (the product of light intensity and exposure interval). The subsequent heat treatment step initiates crystals growth in the glass and can be extended if a colored opal glass rather than a colored clear glass is desired.
Following the first irradiation and heat treatment steps, at least the regions of the photosensitive surface layer to be decorated are again irradiated with ultraviolet light and the article is again heated to a temperature above the transformation range but below the softening point of the photosensitive glass to promote the precipitation of metallic silver therein. The main effect of these subsequent irradiation and heat treatment steps is to fully develop and intensify within the glass the particular hue dictated by the initial irradiation step.
Close examination of the colored regions of photosensitive glasses of the described type has revealed the presence of microcrystals of alkali metal fluoride and metallic silver therein. The coloration observed has not been fully explained, but is thought to be due to the presence in the colored regions of discrete colloidal particles of metallic silver less than about 200A in the smallest dimensions and/or metallic silver contained within a portion of the alkali metal fluoride microcrystals, the silver-containing portion of the microcrystals being less than about 200A in the smallest dimension, and/or a coating of metallic silver on at least a portion of the surface of the alkali metal fluoride microcrystals, the portion of the microcrystals coated with silver being less than about 200A in the smallest dimension.
The exact color developed within a selected portion of the photosensitive surface layer of a laminate provided in accordance with the invention depends upon the composition of the glass as well as on the particular sequence of irradiation and heat treatment steps employed, but suitable processing procedures may readily be determined by routine experiment. A variety of processing techniques are described in the aforementioned U.S. Pat. No. 4,017,318 to Pierson and Stookey and that patent is expressly incorporated herein by reference for a further discussion of the manufacture and treatment of photosensitive glasses.
The invention may be further understood by reference to the following detailed example.
EXAMPLE
A melt for a spontaneous opal core glass having a composition consisting, in parts by weight as calculated from the batch, of about 75.7 parts SiO 2 , 6.23 parts Al 2 O 3 , 16.37 parts Na 2 O, 1.25 parts K 2 O, 4.57 parts F, and 0.17 parts CaO is provided. Glass of this composition has an average linear coefficient of thermal expansion (0°-300° C.) of about 94 × 10 -7 /° C.
A second melt for a photosensitive surface layer glass is also provided, this melt having a composition, in parts by weight as calculated from the batch, of about 72.0 parts SiO 2 , 16.2 parts Na 2 O, 6.9 parts Al 2 O 3 , 5.0 parts ZnO, 2.5 parts F, 1.1 parts Br, 0.01 parts Ag, 0.05 parts CeO 2 , 0.20 parts Sb 2 O 3 and 0.05 parts SnO. Glass of this composition has an average linear coefficient of thermal expansion (0°-300° C.) of about 83 × 10 -7 /° C.
The two melts are combined at a temperature of approximately 1200° C. to provide laminated glass ribbon approximately 0.100 inches in thickness and 3 inches in width, consisting upon cooling of a dense, white opal glass core completely enveloped by a transparent photosensitive glass skin about 0.010 inches in thickness.
A section of glass ribbon about 6 inches in length is cut from the ribbon thus provided and processed to photographically develop color therein. Three selected regions of one side of the ribbon, designated as regions 1, 2, and 3, are chosen for the development of green, red and yellow coloration respectively. The ribbon is positioned approximately 10 inches from a 200-watt mercury arc lamp, and the selected regions are irradiated so that region 1 is exposed to full lamp intensity for 20 seconds, region 2 is exposed for 45 seconds, and region 3 is exposed for 225 seconds.
The irradiated ribbon is then placed in an electric furnace, heated at a rate of about 450° C. per hour to a temperature of about 520° C., held at 520° C. for about 60 minutes, and then cooled to room temperature. Examination of the heat-treated ribbon indicates that the photosensitive skin remains transparent, although the irradiated regions exhibit a slight yellow tint.
The ribbon is then placed on a hot plate and heated to a temperature of about 300° C., maintained at 300° C. for a 30-minute interval during which it is uniformly irradiated with the mercury arc lamp above described. Irradiation is then terminated and the ribbon is cooled to room temperature.
Examination of the ribbon so treated shows that three intensely colored regions, contrasting strongly with the surrounding white color of the opal core, have been provided. Region 1, which was initially irradiated for 20 seconds with the mercury arc lamp, exhibits a bright green color, while regions 2 and 3, irradiated for 45 and 225 seconds, exhibit red and yellow colors, respectively. This decorated laminated ribbon has a modulus of rupture strength (abraded) of about 20,000 psi, which is sufficient to provide excellent resistance to mechanical breakage.
From the foregoing description it is apparent that a wide variety of decorated laminated glass articles useful for many technical and consumer-related applications requiring strength, light weight, and a flexible design capability may be provided within the scope of the invention as defined by the appended claims. | Photosensitive laminated glass useful for providing strong, lightweight glass articles incorporating integral surface decorations resistant to mechanical and chemical deterioration in use are described. | 2 |
BACKGROUND
Mobile devices, such as smartphones and tablets, are becoming increasingly popular. One common feature on such devices is a camera for the capturing of still images or video images. Many devices now have more than one camera, with one mounted on the “front” of the mobile device (e.g., the side with the primary display screen), and a second mounted on the “back” of the mobile device. The primary application for the “back” camera is to record video or images of people, places, or events to which the user of the mobile device is an audience (e.g., family gatherings, concerts, sporting events, landscapes and scenes of nature, or the like). The primary application for the “front” camera is to record video or images of the user or a group of individuals around the user, for example, for a self-portrait or during a video call.
Although mobile device cameras are popular for capturing video or still images, their usefulness is limited by their ability to capture quality images, especially when there is low or no ambient light. Many smartphone manufacturers have added flash devices as a component of the smartphone. These flash devices artificially illuminate the environment or user, but the output of such mobile device-embedded flash devices may be inadequate to illuminate certain scenes. Some manufacturers have developed attachable external illumination or flash devices, which provide increased illumination beyond that of the “internal” mobile device flash device. These devices use bright white light emitting diodes (LEDS), and plug into the 3.5 mm audio in/out port to supply power thereto.
SUMMARY
The following summary is for illustrative purposes only, and is not intended to limit or constrain the detailed description. The following summary merely presents various described aspects in a simplified form as a prelude to the more detailed description provided below.
Several problems with external flash devices have been observed. First, the attachable flash device requires power. In some instances, the device draws power from the mobile device, either to operate or to recharge an internal battery. This may drain power from the mobile device battery. As some situations requiring an external flash are at night (e.g., low-ambient light outdoor conditions, night clubs, or the like), the mobile device battery may be low (e.g., because the user charges the mobile device overnight and has not had an opportunity to charge the battery of the mobile device since earlier in the day). A user may be reluctant to sap power from their mobile device battery by attaching the external flash device. Compounding the power problems, external flash device manufacturers might not design the power circuitry of the external flash device to react to low battery conditions in the mobile device, and a user's mobile device battery may be completely drained by an overzealous external flash device charging its battery.
A second observed problem is that mobile device manufacturers, particularly smartphone manufacturers, may change one or more dimensions of the device (e.g., height, width, length, thickness or the like) or one or more locations of ports (e.g., moving a data port, power adaptor port or audio port from one location on the device to another location on the device, such as from the top to the bottom of the device). An external flash device may be designed for a particular model of mobile devices or class of mobile devices (e.g., an external flash device only for 3.5 mm ports located on the top of the device, an external flash device only for APPLE IPHONE devices, or SAMSUNG GALAXY devices). A user may encounter difficulty, if not outright incompatibility, when moving an external flash device from one mobile device to a second mobile device, even when purchasing a new mobile device from the same manufacturer.
A third observed problem is that external flash devices occupying the 3.5 mm audio input/output port deprive the user of the ability to use headphones and/or microphones. A user recording a video in a low-light condition requiring a microphone and/or headphones must choose between poor video quality or poor audio quality, and a user experience will suffer as a result.
Accordingly, one or more aspects presented herein are directed to the above problems and to other problems that will be apparent upon reading of the following description. An external flash device compatible with one or more mobile devices may be provided. The external flash device may comprise an internal power source. In some aspects, the internal power source may be a replaceable battery (e.g., a CR 2032 battery). In some aspects, the internal power source may be a rechargeable battery (e.g., a lithium-based or nickel-based rechargeable battery). The external flash device may comprise a non-conductive jack or non-conductive male connector, which may be inserted in the corresponding receptor or female connector located on the mobile device. In some aspects, the non-conductive tip may be molded as part of the plastic housing holding the flash components (the LED bulbs). In some aspects, the non-conductive jack may be a 3.5 mm audio jack. In some aspects, the non-conductive male connector may be a Universal Serial Bus (USB) connector. Furthermore, in some aspects the non-conductive male connector may be a micro-USB connector.
In some aspects, the housing may be manufactured in two parts, a first component which includes the jack as part of its moulding, and a second component which includes an opening in a surface to accept a portion of the jack included on the first component.
Additionally or alternatively, an external flash device may comprise an adaptor receiving region. The adaptor receiving region may be configured to accept one of a plurality of adaptors. Each adaptor may include a non-conductive jack or non-conductive male connector, which may be insertable in a corresponding receptor or female connector located on the mobile device. In some aspects, the jack or connector may be moulded as part of the adaptor. In some aspects, the non-conductive jack may be a 3.5 mm audio jack. In some aspects, the non-conductive male connector may be a Universal Serial Bus (USB) connector. Furthermore, in some aspects the non-conductive male connector may be a micro-USB connector.
In another aspect, a non-conductive tip may be positioned to extend from a first surface of an adaptor. The non-conductive tip may be dimensioned for insertion into and frictional engagement with a port of a mobile device. The adaptor may also include a port located on a second surface opposite from the first surface. The port may be dimensioned to receive a tip positioned on a housing of an external flash device.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects, and advantages of the present disclosure will become better understood with regard to the following description, claims, and drawings. The present disclosure is illustrated by way of example, and not limited by, the accompanying figures in which like numerals indicate similar elements.
FIG. 1A and FIG. 1B depict a front view and a rear view, respectively, of an exemplary external flash device according to one or more aspects described herein.
FIG. 2 depicts a front view of an exemplary external flash device according to one or more aspects described herein.
FIG. 3 depicts an isometric view of an example coupling according to one or more aspects described herein.
FIGS. 4A-C illustrates an system of positioning an example adaptor tip in the coupling of FIG. 3 according to one or more aspects described herein.
FIGS. 5A-C illustrate example additional and/or alternative adaptor tips according to one or more aspects described herein.
FIGS. 6A-B illustrate an additional or alternative adaptor mechanism according to one or more aspects described herein.
FIG. 7 illustrates a computing device according to one or more aspects described herein.
FIG. 8 illustrates a kit comprising an external flash device and a plurality of adaptors, according to one or more aspects described herein.
DETAILED DESCRIPTION
In the following description of the various embodiments, reference is made to the accompanying drawings identified above, which form a part hereof, and in which is shown by way of illustration various embodiments in which various aspects of the disclosure may be practiced. Other embodiments may be utilized, and structural and functional modifications may be made, without departing from the scope discussed herein. Various aspects are capable of other embodiments and of being practiced or being carried out in various different ways. In addition, the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. Rather, the phrases and terms used herein are to be given their broadest interpretation and meaning. The use of “including” and “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof.
FIG. 1A and FIG. 1B illustrate an exemplary external flash device 100 according to one or more aspects described herein, with a front view depicted in FIG. 1A and a rear view depicted in FIG. 1B . An external flash device 100 may comprise one or more light sources 110 , which may be in some aspects light emitting diodes (LEDs). As depicted in FIG. 1 , the light sources 110 may be arranged in a grid format (e.g., an m by n matrix). For example, as shown in FIG. 1A , a grid may include twenty light sources arranged in a four by five matrix, but other configurations (e.g., four by four, two by two, three by three, three by five) are possible and within the scope of the present disclosure. The light sources may be planar (e.g., surface mounted LEDs, rectangular-dimensioned LEDs) and/or may be three-dimensional (e.g., “lamp-type” LEDs affixed via leads). Light sources 110 may emit light in one direction (e.g., unidirectional) or multiple directions (e.g., omnidirectional) A reflector 120 may be provided to direct light away from the surface of the external flash device 100 . Additionally, glass or translucent plastic may be placed over the light sources to protect the light sources from damage and/or to modulate the output of the light sources (e.g., via focusing or diffusing the output of the light sources).
The light sources may be connected to circuitry (not shown) which may control the power and/or operation, including output, of the light sources. The circuitry may be controlled by a controller via one or more physical control inputs (e.g., switches, knobs, touch-based inductive and/or capacitive inputs, or the like) such as toggle 127 . Additionally and/or alternatively, the circuitry may be controlled wirelessly (e.g., via commands or instructions received via a wireless transceiver, such as a BLUETOOTH transceiver, including commands received from operation of an application running on a mobile device). In some aspects, the controller may be optional, as for example, where a physical control input toggled by the user causes completion of a circuit, enabling the flow of current from a power source to the light sources. In such an example, a variable resistor controllable by the user may be arranged so as to modulate the power received at the light sources, and accordingly control the output of the light sources.
The external flash device may also comprise an internal power source, such as a battery 126 . In some aspects, the internal power source may be user-accessible via a compartment door 125 on the rear surface of the device 100 . In some aspects, the internal power source might not be user-accessible, and as a result compartment door 125 might not be present. In some aspects, the shape and size of compartment door may be different from that depicted in FIG. 1B .
The internal power source may be a replaceable battery, such as (for example) a circular-shaped CR-2032 battery, or may be a cylindrical-shaped AAA-cell battery. In some aspects, the battery may be chargeable or rechargeable. For example, the battery may be a lithium-based (e.g., lithium-ion) battery, or the battery may be a nickel-based (e.g., nickel-cadmium) battery. A battery may be chargeable by connecting the external flash device via a wire, cord, cable, or the like to an external power source via a power connector present on the housing of the external flash device (not shown).
The above-discussed components, along with other components, may be stored in a housing 140 . Housing 140 may be formed from plastic, such as a thermoplastic (e.g., acrylonitrile butadiene styrene (ABS), polycarbonate, polylactic acid (PLA or polylactide), polyethylene (including high-density, medium-density, low-density, or other formations of polyethylene), polyvinyl chloride, polypropylene, or other like plastics and/or thermoplastics. Housing 140 may be formed via any type of injection moulding, three-dimensional printing, or other similar manufacturing process.
The external flash device may include a non-conductive tip 150 . In some aspects, a non-conductive tip may be configured to not allow or transmit signals, such as power or communication signals between the circuitry of the device 100 and another device. Although the exemplary tip 150 illustrated in FIGS. 1A and 1B is in the shape of a cylindrical tip-ring-sleeve (TRS) connector having a 3.5 millimeter (mm) diameter, such exemplary tip 150 is only one of many possibilities. Other examples, not shown with respect to FIG. 1 , include tip-sleeve (TS) connectors and tip-ring-ring-sleeve (TRRS) connectors of various diameters (e.g., 6.35 mm, 2.5 mm, or the like), Universal Serial Bus (USB) connectors (USB-A, USB-B, USB-C, microUSB, miniUSB, or the like), or connectors specific to and/or commonly associated with a device or manufacturer of devices (e.g., the 30-Pin connectors or Lightning connectors found on devices manufactured by APPLE INCORPORATED, or the like). The shape and dimensions of any type of tip, jack, male connector, or so on, which may be positionable in a corresponding receptor, port, input, female connector or so on located on the mobile device may be used.
Upon insertion into a female connector or port located on the mobile device, tip 150 may engage frictionally with the sidewalls of the female connector or port, enabling a temporary coupling with of housing 140 and tip 150 with the body of the mobile device. The frictional engagement may be overcome upon presentation of a force to the housing 140 /tip 150 to remove the tip 150 from the female connector or port of the mobile device. The non-conductive tip might not allow the external flash device 100 to draw power from the mobile device and might not facilitate communication between the components of the external flash device 100 and the mobile device.
Housing 140 and tip 150 may be manufactured as part of a single process or series of processes. Although housing 140 and tip 150 are depicted to be different colors in FIGS. 1A and 1B , in some aspects housing 140 and tip 150 may be the same color. In some aspects, the housing may be manufactured as a shell having a first piece and a second piece, which may be formed separately and coupled together (temporarily or permanently) after one or more flash device components (e.g, circuitry, light sources) are positioned within the shell. The coupling may be by way of frictional engagement, press-fitting, or other affixing mechanisms (e.g., screws, glue, thermoforming of plastic, and so on). In some aspects, the tip may be formed separately and placed within an opening of one of the housing shell components such that the tip or a portion thereof extends beyond the housing surface. When the first and second pieces of shell are positioned together, portions of the tip may extend through a hole formed by the positioning of openings located on the first and second pieces.
The tip and housing may be formed from different materials and/or plastics. For example, a first material may be selected for reflective or heat-resistant properties to form the body of the housing, as the light sources may emit heat or it may be desirous to reflect light emitting therefrom. A second material may be selected for frictional or hardness properties to form the non-conductive tip, which may assist the tip 150 to engage frictionally with the female connector or port of the mobile device without breaking, as stresses on the tip may develop in use of the mobile device with the external flash device attached.
In some aspects, tip 150 may be molded as part of the plastic housing holding the flash components (the LED bulbs), either during the manufacturing process of the housing prior to assembly of the external device (e.g., by forming the plastic housing to comprise the tip 150 ) or as part of a post-manufacturing finishing step (e.g., attaching the tip 150 to a completed housing by gluing, affixing, soldering, thermoforming plastic, or the like). As above, the housing may be manufactured in pieces as shell components, one or more of which may include the tip 150 or portions thereof. For example, a first piece of the housing having the tip 150 may be formed. A second piece of the housing may be formed which may be joined (temporarily or permanently) after placement of one or more flash device components (e.g., the light sources) within an internal compartment or compartments formed by the housing pieces. In some aspects, the tip formed as part of the first piece of housing may overlap with a recess or groove in the second piece designed and positioned for accepting the overlap. In some aspects, the tip may be divided and portions may be formed on both a first and second piece (e.g., a front piece and a back piece) so that, when the first and second pieces are coupled, the tip portions of each are also coupled, which may form a tip having dimensions allowing the tip to be accepted into a port, female connector, or the like on the mobile device.
FIG. 2 depicts a front view of another external flash device 200 according to one or more aspects described herein. The external flash device 200 includes similar light source components and control components as discussed above with respect to the external flash device of FIGS. 1A and 1B , and reference is made to the above discussion regarding such components. However, the external flash device 200 comprises an adaptor receiving region 210 . Although the adaptor receiving region 210 is depicted as having a largely square or rectangular form, other shapes of adaptor receiving regions 210 are within the scope of the present disclosure. For example, the adaptor receiving region 210 may be ellipsoidal, circular, triangular, or any other shape. Adaptor receiving region 210 may include left groove 215 and right groove 220 .
FIG. 3 presents an isometric view of adaptor receiving region 210 , viewed from the bottom of the external flash device 200 . Illustrative screws 240 may affix the adaptor receiving region 210 to a housing 260 of the external flash device. In some aspects, illustrative screws 240 are optional. For example, the housing 260 may be plastic and formed (e.g., thermoformed) or moulded to include the adaptor receiving region 210 . In some aspects, other coupling (e.g., glue, epoxy, resin, or the like) may be used in place of screws 240 to affix adaptor receiving region 210 with housing 260 .
FIG. 4A illustrates an exemplary adaptor 400 insertable into the adaptor receiving region 210 . Adaptor 400 may include a base 410 and a non-conductive tip 420 . As discussed above, although the exemplary tip 420 illustrated in FIG. 4A is a microUSB male connector, other tips, jacks, male connectors, or the like may be present on the surface of base 410 .
For example, as depicted in FIG. 5A , a tip 510 of an adaptor 515 may be a cylindrical TRS connector having a 3.5 mm diameter, or may be any other TS connector or TRRS connector of various diameters (e.g., 6.35 mm, 2.5 mm, or the like). As another example, as depicted in FIG. 5B , a tip 520 of an adaptor 525 may be in the shape of any USB connector, such as a USB-A connector or USB-B, USB-C, microUSB, miniUSB, or the like. As another example, as depicted in FIG. 5C , tip 530 of an adaptor 535 may be in the shape of any connector specific to and/or commonly associated with a device or manufacturer of devices (e.g., the 30-pin connector or Lightning connector found on devices manufactured by APPLE INCORPORATED, or the like). Any type of tip, jack, male connector, or so on, which may be positionable in a corresponding receptor, port, input, female connector or so on located on the mobile device may be used.
FIGS. 4B and 4C illustrate the insertion of adaptor 400 into adaptor receiving region 210 , thereby forming assembly 430 . FIGS. 4B and 4C are an isometric view of the adaptor receiving region with the external flash device to the right of the view (as indicated by illustrative screws 240 , which are passed through the flat surface facing the view to couple the adaptor receiving region to the housing of the external flash device). As illustrated, the base of the adaptor 400 may be slid into a channel of adaptor receiving region 210 formed by left groove 215 and right groove 220 . In some aspects, the adaptor receiving region 210 may present a complementary mating structure for one or more removable attachments (e.g., the adaptor 400 ). With additional reference to FIG. 3 , in some aspects, the left grove 215 and right groove 220 may provide engagement with an adaptor insertable into the channel formed by the grooves and the flat surface through which the illustrative screws 240 have been passed. The left groove 215 and right groove 220 may not be parallel so as to provide frictional engagement with the adaptor base. Once the base is pressed into the adaptor receiving region to a position where the distance between left groove 215 and right groove 220 is less than the inserted width of the base 410 , the non-parallel groves may inhibit movement of the base, thereby frictionally engaging the base with the adaptor receiving region (and consequently, because the adaptor receiving region is coupled with the external flash device, the base and tip may be coupled via the adaptor receiving region with the external flash device 200 ). In some aspects, the adaptor base may be insertable into the channel in multiple arrangements. For example, base 410 may be rotated so that the micro-USB connector depicted in FIGS. 4A-C is in a vertical orientation when inserted into the adaptor receiving region 210 .
Other mechanisms to engage the base 410 with the adaptor receiving region are within the scope of the present disclosure, although not illustrated in FIGS. 2-4 . For example, the adaptor receiving region 410 may have a lever-based locking mechanism. The lever may be moved in one direction to open the channel formed by the left groove 215 and right groove 220 and may be moved in an alternative direction upon presentation of a base of an adaptor, the mechanics of which may press the adaptor base into engagement with the adaptor receiving region. Snap members, magnets, thumb screws, bayonet couplings, or other locking mechanisms may be utilized in place of or in addition to press-fitting adaptor base 410 into the channel of the adaptor receiving region. As an example, in some aspects, left groove 215 and/or right groove 220 may have holes for engagement with a retractable spring-loaded pin or pins present on the adaptor base. Upon sliding of the adaptor into the adaptor receiving region, the spring-loaded pin or pins may encounter the holes, causing the spring to expand, thereby coupling the adaptor base to the adaptor receiving region by way of alignment and engagement of the pins with the holes.
FIGS. 6A and 6B depict another adaptor according to one or more aspects described herein. The adaptor of FIGS. 6A and 6B may be used with external flash devices, such as external flash device 100 of FIG. 1 and other external flash devices. FIG. 6A presents an isometric view of an adaptor 600 with exemplary non-conductive tip 610 (a micro-USB tip). FIG. 6B presents a different isometric view of adaptor 600 with port 620 . Tip 610 may be any of the non-conductive tips discussed above (e.g., any diameter of TRS, TS, or TRSS jack, and/or any mini-USB, USB-A, USB-B, USB-C, or Lightning connector, or any other jack, connector, or the like designed for insertion into a corresponding port or female connector). Port 620 may be a cylindrical TRS female connector having a 3.5 mm diameter, though may be any port capable of receiving an external flash device, in accordance with one or more aspects not illustrated in FIG. 6 .
A user may insert into port 620 of adaptor 600 an external flash device having a tip. The tip may be a conductive tip. The presentation of non-conductive tip 610 to a corresponding port or female connector of the mobile device may result in no power being drawn by the external flash device, which would normally draw power as a result of its conductive tip. Accordingly, impact to a power source (e.g., battery) of the mobile device may negligible. In some aspects, circuitry may be present in adaptor 600 which may be controlled via a physical control (e.g., knob, switch, gate, relay or the like) or wirelessly controlled (e.g., via BLUETOOTH or other wireless technology such as IEEE 802.11 or IEEE 802.15, or the like) to temporarily allow current to flow from the port to the external flash device. This may be desired to recharge a battery of the external flash device without necessitating removal of the adaptor 600 .
FIG. 7 schematically illustrates general hardware elements that may be used to implement any of the various computing devices discussed herein, including for example the various controllers discussed herein which may control the light sources of an external flash device and may be in communicative contact with applications running on the mobile device. In some aspects, the mobile device may include the general hardware elements discussed herein. The computing device 700 may include one or more processors 701 , which may execute instructions of a computer program to perform any of the features described herein. The instructions may be stored in any type of computer-readable medium or memory, to configure the operation of the processor 701 . For example, instructions may be stored in a read-only memory (ROM) 702 or random access memory (RAM) 703 . The computing device 700 may also include one or more input interfaces 708 and one or more network interfaces, such as a network input/output (I/O) circuit 709 . The network input/output circuit 709 may be a wired interface, wireless interface, or a combination of the two. The computing device 700 may also include a power source 707 , which may be coupled to one or more physical control inputs (e.g., switches, knobs, touch-based inductive and/or capacitive inputs, or the like) such as toggle 717 . Although only a connection between the processor 701 and the power source 707 is shown, in some aspects there may be connections between the power source and the other components (e.g., ROM 702 , RAM 703 , input interfaces 708 , and/or network I/O 709 ) as well.
The FIG. 7 example is a hardware configuration, although the illustrated components may be wholly or partially implemented as software as well. Modifications may be made to add, remove, combine, divide, etc. components of the computing device 700 as desired. Additionally, the components illustrated may be implemented using basic computing devices and components, and the same components (e.g., processor 701 , ROM storage 702 , etc.) may be used to implement any of the other computing devices and components described herein. For example, the various components herein may be implemented using computing devices having components such as a processor executing computer-executable instructions stored on a computer-readable medium, as illustrated in FIG. 7 . Some or all of the entities described herein may be software based, and may co-exist in a common physical platform.
FIG. 8 illustrates a kit 800 comprising a device (e.g., device 100 or device 200 ) and one or more adaptors which may be inserted into an adaptor receiving region 810 (e.g., adaptor 805 , adaptor 815 , and adaptor 825 ). In some aspects, the kit 800 may include a plurality of adaptors each of which has a mating structure which is complementary to the adaptor receiving region. In some aspects, the kit 800 may include a plurality of adaptors which are compatible with a certain device or family of mobile devices (e.g., a model of mobile devices, a manufacturer of mobile devices, or the like).
One or more aspects of the disclosure may be embodied in a computer-usable data and/or computer-executable instructions, such as in one or more program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types when executed by a processor in a computer or other data processing device. The computer executable instructions may be stored on one or more computer readable media such as a hard disk, optical disk, removable storage media, solid state memory, RAM, etc. As will be appreciated by one of skill in the art, the functionality of the program modules may be combined or distributed as desired in various embodiments. In addition, the functionality may be embodied in whole or in part in firmware or hardware equivalents such as integrated circuits, field programmable gate arrays (FPGA), and the like. Particular data structures may be used to more effectively implement one or more aspects of the disclosure, and such data structures are contemplated within the scope of computer executable instructions and computer-usable data described herein.
Although example embodiments are described above, the various features and steps may be combined, divided, omitted, rearranged, revised and/or augmented in any desired manner, depending on the specific outcome and/or application. Various alterations, modifications, and improvements will readily occur to those skilled in art. Such alterations, modifications, and improvements as are made obvious by this disclosure are intended to be part of this description though not expressly stated herein, and are intended to be within the spirit and scope of the disclosure. Accordingly, the foregoing description is by way of example only, and not limiting. This patent is limited only as defined in the following claims and equivalents thereto. | Apparatuses and systems are provided for enabling a user to connect an external flash device to a mobile device, such as a smartphone or tablet. Non-conductive tips may be provided, either as an integrated component of a housing of an external flash device or via an adaptor receiving region and adaptor. The availability of different tips and/or adaptors enables the user to utilize multiple accessories (e.g., a microphone) in combination with the external flash. The non-conductive tips may be 3.5 millimeter audio jacks or Universal Serial Bus (USB) type male connectors or device/manufacturer specific connectors. The non-conductivity of the tip prevents power from being drawn from the mobile device, improving the battery life of the mobile device. Power may be provided to the external flash device from a replaceable or rechargeable battery. An adaptor configured to receive a conductive tip and provide a non-conductive tip is also disclosed. | 6 |
CROSS REFERENCE TO THE RELATED APPLICATION
The present application has been filed with claiming priority based on Japanese Patent Application No. 2002-339796, filed on Nov. 22, 2002. Disclosure of the above-identified Japanese Patent Application is herein incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to an original reading apparatus for performing reading of an original, such as a facsimile apparatus, a copy machine, a scanner and so forth. More particularly, the invention relates to an original reading apparatus using an optical system elongating an optical path length by turning a light beam by means of a mirror.
2. Description of the Related Art
An original reading apparatus has been used not only in office but also in home in applications of electronizing of various materials, taking in image data from an exposed film and so forth. Particularly, as the original reading apparatus used in home or small scale office, compact one is preferred. Such compact original reading apparatus frequently employs a scanner module constructed with a linear image sensor in which a plurality of reading elements are aligned in a primary scanning direction, and a compressing optical system forming an image of a sheet form original or original, such as book or the like on the primary image sensor as compressed image, and a light source, as a unit for reading the image. The scanner module moves within a given casing in an auxiliary scanning direction perpendicular to the primary scanning direction. At this time, a two dimensional image information of the original mounted on a flat plate form platen glass arranged in the upper portion of the casing, is read.
On the other hand, even in such compact original reading apparatus, there is an increasing demand for reading the original with a plurality of magnifications. For instance, if it is possible to set a film on the platen glass and to read an enlarged image, it becomes unnecessary to separately buy a dedicated film scanner. Attempting to obtain images of a plurality of magnifications using the same linear image sensor, it becomes necessary to vary a distance between the original or object to a lens and a distance between the lens and the linear image sensor, and in conjunction therewith, to vary a focal distance of the lens so that the image can be formed on the linear image sensor in the condition where the distances are varied.
FIG. 7 illustrates a major portion of an optical system of the conventionally proposed copy machine disclosed in Japanese Unexamined Patent Publication No. 2001-109079. In the lower side of the platen glass 11 , first and second optical scanning portions 12 and 13 arranged for reciprocal motion in lateral direction in the drawing (auxiliary scanning direction), a lens 14 arranged therebetween, a photosensitive drum 15 exposing the image and a sixth mirror 16 guiding a light output from the second optical scanning portion to the photosensitive drum 15 .
The first optical scanning portion 12 is constructed with a light source 18 illuminating a linear reading position of the platen glass 11 (direction perpendicular to drawing sheet surface) and first to third mirrors 21 to 23 respectively reflecting a reflected light of the original (not shown) by illumination of the reading position by the light source 18 . A light reflected by the third mirror 23 incides to the second optical scanning portion 13 via the lens 14 . The second optical scanning portion 13 sequentially reflects the incident light by fourth and fifth mirrors 24 and 25 to incide the output light of the second optical scanning portion 13 to the sixth mirror 16 . This arrangement of the optical system shown in FIG. 7 is to form an image of equal magnification (100%) on the photosensitive drum 15 .
FIG. 8 is an illustration for explaining a relationship between a magnification and object, lens and the image forming position. Assuming that a distance between an object 31 having a length A and a lens 32 is a, and a distance between the lens 32 and an image 32 having a length B and formed at a focal position of the linear image sensor or the like is b, a magnification B/A of the image 33 can be expressed by a ratio of two distances b/a. Therefore, in the technology shown in FIG. 7 , the ratio b/a of the distances is varied by individually moving the first optical scanning portion 12 , the second optical scanning portion 13 and the lens 14 for setting various magnification.
FIG. 9 shows the case where a magnification is 50%, and in contrast, FIG. 10 shows the case where a magnification is 200%. As can be seen, position of the lens 14 is relatively shifted laterally (left and right direction in the drawing). By this, the ratio b/a of the distances is varied. Of course, in practical reading of the image, the first optical scanning portion 12 is moved (performs auxiliary scan) from a left side end in the drawing to a right side end relative to the platen glass 11 . Associating with this, the second optical scanning portion 13 and the lens 14 are also moved with maintaining positional relationship.
Even in the technology disclosed in Japanese Unexamined Patent Publication No. 06-27539, an optical system in which light beam is sequentially turned by six mirrors, similarly, is prepared, and magnification is varied by shifting the positions of lens and mirror are shifted toward the object side or the image forming side.
On the other hand, in the technology disclosed in Japanese Unexamined Patent Publication No. 06-27539, a plurality of magnifications are stored in storage means, and these magnifications can be set easily. In addition, in the technology disclosed in Japanese Unexamined Patent Publication No. 11-305356, four mirrors are used and magnification is varied by shifting the mounting position of the lens or exchanging the lens, and in conjunction therewith shifting the focal position where the photosensitive material is arranged.
As set forth above, conventionally, in the original reading apparatus, it has been typically known to certainly obtain an optical length by sequentially turning the optical paths at respective mirrors using a plurality of mirrors in order to form the image of the original on the image sensor or the photosensitive body using relatively narrow space. Thus, upon varying magnification in stepwise manner or sequentially in the original reading apparatus set forth above, variation of magnification is achieved by varying the relative position of the lens or mirror or focal position without varying number of turns of the optical path with respect to these mirrors.
Therefore, these shifting mechanism of the original reading apparatus can be complicated. Furthermore, when the magnification of the optical system is varied significantly, shifting magnitudes of respective parts become large. On the other hand, even when a plurality of mirrors used, necessity is caused to certainly obtain sufficient length in auxiliary scanning direction in order to acquire optical path length even when a plurality of mirrors are used. As a result, the overall original reading apparatus becomes bulky to make it impossible form the compact original reading apparatus to employ the mechanism significantly varying the magnification.
SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention to provide an original reading apparatus which can realize stepwise or sequential variable magnification using relatively small size optical system upon reading an original.
According to one aspect of the present invention, an original reading apparatus comprises:
a first magnification varying mirror arranged in an optical path from a reading position of an original to an image forming portion across an image forming lens and reflecting a light from the reading position of the original; a second magnification varying mirror arranged with placing a reflection surface in opposition to a reflection surface of the first magnification varying mirror and reflecting a light reflected from the first magnification varying mirror for a plurality of times between the first and second magnification varying mirrors, and thereafter reflecting toward the image forming lens; and reflection times setting means for setting number of times between the first and second magnification varying mirrors by varying an angle of the reflection surface of at least one of the first and second magnification varying mirrors depending upon a designated original reading magnification.
Namely, with the original reading apparatus according to the present invention, angle or angles of reflection surface or reflection surfaces of one or both of first and second magnification varying mirrors are varied by reflection times setting means for varying the optical path length depending upon the original reading magnification to realize variation among a plurality of magnifications in stepwise manner or sequential manner. Since number of times of turning of the reflection light can be varied between two mirrors, down-sizing of the original reading apparatus can be accomplished in the extent corresponding to the extent of variation of the optical path length by turning. It should be noted that the present invention should not be limited to the case where the magnifications are set sequentially, but can be number of variation of magnifications in number corresponding to number of variation of number of times of turning. Of course, sequential variation of magnification in the original reading apparatus can be achieved by varying the distance between the first magnification varying mirror and the second magnification varying mirror or by varying the distance to other optical parts.
Preferably, the reflection times setting means varies angle of the reflection surface of at least one of the first and second magnification varying mirrors by rotating a motor in a magnitude corresponding to the original reading magnification set by an operating portion.
When the original reading apparatus is applied to the scanner or facsimile machine, a linear image sensor is set in an image forming portion, the first and second magnification varying mirrors, the image forming lens and a linear image sensor are assembled as single optical module, the optical module is shifted in an auxiliary scanning direction perpendicular to a primary scanning direction when the linear image sensor performing reading of an image on the original in the primary scanning direction per one line.
Since number of times of turning the reflected light between the first magnification varying mirror and the second magnification varying mirror can be set, down-sizing of the overall original reading apparatus becomes possible.
In the particular embodiment, the image forming lens is positionally fixed within the optical module, and further comprises linear image sensor moving means for moving a reading position of the image of the linear image sensor depending times of reflection when the reflection times setting means sets times of reflection depending upon the original reading magnification.
By fixing the optical lens and moving the linear image sensor by the linear image sensor moving means, the image of the reading position of the original can be formed accurately at the image reading position. It is also possible to fix the linear image sensor and to move the optical lens, or to move both.
The original reading apparatus may further comprise a position adjusting mirror reflecting a light emitted from the reading position of the original for inciding to the first magnification varying mirror and reading position adjusting means for adjusting the original reading position in the auxiliary scanning direction by controlling a rotation angle of the position adjusting mirror.
In the present invention, since number of times of turning of the reflection light between the first and second magnification varying mirrors can be varied, one or both of the reflection surfaces of these magnification varying mirrors are rotated to vary incident angles of the first magnification varying mirrors. By this, when magnification is differentiated, the original reading position can be varied in the auxiliary scanning direction. Therefore, when the original reading position is required to be constant irrespective of magnification, the rotation angle of the position adjusting reflection mirror is controlled.
When the original reading position is located on the surface of a platen glass, on which the original is mounted, when the sheet form original is tightly contacted with the platen glass, focus can be established by positioning of the object.
On the other hand, the original reading position located at a position away from a surface of a platen glass, is effective in the case where a film surface is located at a position distanced from the platen glass by a given distance. Particularly, when the image is to be read with expansion, strict setting of the reading position becomes possible. This is practically advantageous for the original reading apparatus has the original reading position different from the reading position of the sheet form original.
The original reading apparatus may further comprise optical path varying means deflecting a light reflected from the second magnification varying mirror to the longitudinal direction of the optical module, and the image forming lens is arranged between the optical path varying means and the linear image sensor. With such constriction, when the linear image sensor is small in certain extent, length of the optical module in the auxiliary scanning direction can be set shorter. As a result, the length of the original reading apparatus in auxiliary scanning direction can be shortened. On the other hand, by deflecting the light in parallel to the platen glass instead of downward direction of the platen glass perpendicular to the optical module, length of the optical module in this direction can be shortened to reduce thickness of the original reading apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood more fully from the detailed description given hereinafter and from the accompanying drawings of the preferred embodiment of the present invention, which, however, should not be taken to be limitative to the invention, but are for explanation and understanding only.
In the drawings:
FIG. 1 is a perspective view showing an external appearance of one embodiment of an original reading apparatus according to the present invention;
FIG. 2 is a perspective view showing parts arrangement relationship of a major part of the shown embodiment of a scanner module;
FIG. 3 is a side elevation illustrating a platen glass and the scanner module in the shown embodiment;
FIG. 4 is an explanatory illustration of the major part of an optical system of the case where number of times of turning of a reflection light by second and third mirrors is eight times in the shown embodiment;
FIG. 5 is an explanatory illustration of the major part of an optical system of the case where number of times of turning of a reflection light by second and third mirrors is six times in the shown embodiment;
FIG. 6 is an explanatory illustration of the major part of an optical system of the case where number of times of turning of a reflection light by second and third mirrors is four times in the shown embodiment;
FIG. 7 is an illustration showing a general construction showing arrangement of an optical system of the conventionally proposed copy machine in the case of equal magnification;
FIG. 8 is an explanatory illustration showing a relationship between a magnification, object, lens and image forming position;
FIG. 9 is an illustration showing a general construction showing an arrangement of an optical system when a magnification set in the copy machine shown in FIG. 7 is 50%; and
FIG. 10 is an illustration showing a general construction showing an arrangement of an optical system when a magnification set in the copy machine shown in FIG. 7 is 200%.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will be discussed hereinafter in detail in terms of the preferred embodiment of an original reading apparatus according to the present invention with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be obvious, however, to those skilled in the art that the present invention may be practiced without these specific details. In other instance, well-known structures are not shown in detail in order to avoid unnecessary obscurity of the present invention.
FIG. 1 illustrates an external appearance of one embodiment of an original reading apparatus according to the present invention. The show embodiment of the original reading apparatus 101 has a cover 103 arranged on an upper surface of an apparatus body 102 for opening and closing. Below the cover 103 , a not shown platen glass is present. Below the platen glass, a pair of guide rails 104 and 105 are arranged in parallel with each other. On these guide rails 104 and 105 , a scanner module (optical module) 106 for performing reading of an image is fitted thereover and is reciprocally driven in an auxiliary scanning direction as length direction of the guide rails 104 and 105 , by a not shown driving source.
The apparatus body 102 has a structure, in which an upper body portion 102 A and a lower body portion 102 B are stacked vertically. In the front side of the upper body portion 102 A in the drawing, a control panel 109 having an operating portion 107 performing operation for reading the image and a display portion 108 for performing necessary display on an operation surface.
FIG. 2 is an illustration showing a relationship of parts arrangement with respect to the major part of the scanner module (optical module) as viewed obliquely upper side, and FIG. 3 is an illustration of the platen glass and the scanner module as viewed from lateral side. The scanner module 106 has a bar-shaped light source 124 illuminating an original 122 on the platen glass 121 including a reading position 123 . A reflection light originally emitted from the light source 124 and reflected by the original 122 incides to a first mirror 126 to be reflected obliquely upward. The first mirror 126 has a rotary shaft (not shown) in the longitudinal direction so that rotation angle can be adjusted by means of a first motor (M 1 ) 127 1 . A reflection light 128 of the first mirror 126 incides to a third mirror 130 among second and third mirrors 129 and 130 arranged in substantially parallel relationship with a predetermined distance. The third mirror 130 has a rotary shaft (not shown) in longitudinal direction for varying times of turning by reflection of the reflection light 128 between the third mirror 130 and the second mirror 129 by rotation over fine angle by means of a second motor (M 2 ) 127 2 . In case of the example shown in FIGS. 2 and 3 , respectively three times of reflection is performed by the second mirror 129 and the third mirror 130 .
A final reflection light 131 by the second mirror 129 incides to a fourth mirror 132 arranged immediately below the third mirror 130 , and is reflected substantially perpendicularly downward as a reflection light 133 . The reflection light 133 is reflected in a direction substantially parallel to the platen glass 121 ( FIG. 3 ) by a fifth mirror 134 as a reflection light 135 . The reflection light 135 incides to a sixth mirror 136 . A direction of a reflection light 138 by the sixth mirror 136 matches with an optical axis of an image forming lens 137 consisted of a plurality of lenses. The reflection light 138 is converged by the image forming lens 137 to form an image on a linear image sensor 140 consisted of CCD (Charge Coupled Device) fixed on a mounting plate 139 and then subject to photoelectric conversion. In the shown embodiment, the image forming lens 137 is fixed. The first image sensor is driven to move relative to the image forming lens by means of a third motor (M 3 ) 127 3 for adjusting a distance to the image forming lens 137 . It should be noted that in certain apparatus, a part of first to third motors 127 1 to 127 3 can be eliminated.
On the other hand, when a magnification for reading the original 122 by the linear image sensor 140 is varied, the reading position 123 can be varied. When the reading position 123 is varied, it becomes necessary to adjust the position to initiate reading per magnification to make control complicate. Therefore, in the shown embodiment of the original reading apparatus, number of times of turning of the reflection light 128 is controlled by the second motor 127 1 , and in conjunction therewith, by adjusting rotation angle of the first mirror 126 , the reading position 123 is kept constant irrespective of magnification. In order to maintain the reading position 123 constant, the sensor 141 is arranged outside of the reading region of the original 122 on the platen glass 121 .
FIGS. 4 to 6 show the cases where number of times of turning of the reflection light by the second and third mirrors is varied. Amongst, in FIG. 4 , by setting an angle θ 1 of the third mirror 130 relative to the second mirror 129 , eight times in total of turning of the reflection light is caused between the second and third mirrors 129 and 130 to elongate an optical length by these optical parts.
On the other hand, in FIG. 5 , by setting a tilting angle of the third mirror 130 relative to the second mirror 129 at an angle θ 2 greater than the angle θ 1 of the example of FIG. 4 , six times in total of turning of the reflection light is caused between the second and third mirrors 129 and 130 to elongate an optical length by these optical parts.
Furthermore, in FIG. 6 , by setting a tilting angle of the third mirror 130 relative to the second mirror 129 at an angle θ 3 greater than the angle θ 2 of the example of FIG. 5 , six times in total of turning of the reflection light is caused between the second and third mirrors 129 and 130 to elongate an optical length by these optical parts.
Here, it is assumed that a distance between the second mirror 129 and the third mirror 130 is constant, and the position of the optical lens 137 or the linear image sensor 140 shown in FIG. 2 or 3 , is fixed. In this case, among three examples shown in FIGS. 4 to 6 , the optical system shown in FIG. 4 establishes the most compressed magnification, and the optical system shown in FIG. 6 establishes the most expanded magnification. If such assumption is not established, for example, when the position of the linear image sensor 140 is fluctuated by the third motor 127 3 as in the shown embodiment, a distance b in a distance ratio b/a shown in FIG. 8 is differentiated. Accordingly, among three examples shown in FIGS. 4 to 6 , it is not possible to determine the arrangement of the optical system as to which magnification is to be set.
Therefore, in the shown embodiment of the original reading apparatus 101 , when an operator designates a certain magnification through the operating portion 107 shown in FIG. 1 , information relating to a rotation angle corresponding to magnification is read out from the not shown ROM (read-only-memory). Then, an angle is set by the second motor 127 2 . Thereafter, when the first motor 127 1 is rotated to adjust the reading position 123 of the original 122 , and the third motor 127 3 moves the mounting plate 139 for correcting focal position in the relevant magnification. Here, adjustment of the reading position 123 by the first motor 127 1 is performed by positioning relative to the sensor 141 .
Once adjustment of the optical system is performed as set forth above, in a condition where relationship of arrangement upon completion of adjustment set forth above, the scanner module 106 shown in FIG. 1 is moved in the auxiliary scanning direction perpendicular to the longitudinal direction (primary scanning direction) of the scanner module 106 . By this, reading of a two-dimensional image of the original 122 ( FIG. 2 ) is performed.
In case of the shown embodiment of the scanner module 106 as set forth above, after establishing the optical path in parallel to the platen glass 121 ( FIG. 3 ) by the fifth mirror 134 , the optical path is deflected into the longitudinal direction of the scanner module 106 by the sixth mirror 136 . By this, the moving direction of the optical lens 137 or the linear image sensor 140 becomes the axial direction (primary scanning direction) of scanner module 106 . Accordingly, the length in the height direction and auxiliary scanning direction of the scanner module 106 can be shortened to contribute for down-sizing of the module per se.
If there is no positive demand for down-sizing, various modification may be provided in the arrangement of the optical system for guiding the reflected light 133 as shown in FIG. 3 . For instance, the linear image sensor 140 may be arranged below the third mirror 130 with orienting the sensor surface upwardly. On the other hand, it is also possible to arrange the linear image sensor 140 in the longitudinal direction of the scanner module 106 . By this, number of mirrors can be reduced.
Furthermore, in the embodiment, while the second mirror 129 is fixed, it is also possible to rotate this in place of the third mirror 130 . Of course, it is further possible to perform control for rotating both of the second mirror 129 and the third mirror 130 .
On the other hand, in the embodiment, discussion has been given for the case where the original 122 is placed in contact with the platen glass 121 . In this case, the position of the object can be regarded as substantially the position of the upper surface of the platen glass 121 . However, in case of the original reading apparatus having a function for reading the image on the photo film, it is typical to mount a stripe form film on the platen glass 121 with setting in a not shown film holder. In such case, for a height of the portion where the film is set with the film holder, the film as the object is lifted away from the platen glass 121 . Accordingly, when the film holder is used, focal depth should be deepened for lifting amount or position or respective portions should be adjusted with taking the lifting amount into account.
Furthermore, in the embodiment, there are shown examples to turn the optical paths for four to eight times between two mirrors. However, number of times of turning between these mirrors can be two or three times or more than eight times. On the other hand, at the final image forming position, it is naturally possible to arrange other reading means, such as photosensitive body or the like, or an image recording means in addition to the linear image sensor.
As set forth above, with the present invention, angle or angles of reflection surface or reflection surfaces of one or both of first and second magnification varying mirrors are varied by reflection times setting means for varying the optical path length depending upon the original reading magnification to realize variation among a plurality of magnifications in stepwise manner or sequential manner. Therefore, down-sizing of the original reading apparatus can be accomplished in the extent corresponding to the extent of variation of the optical path length by turning. Since number of times of reflection of the reflection light between the first magnification varying mirror and the second magnification varying mirror is varied depending upon reading magnification of the original, substantial down-sizing of the space to be occupied by the optical system can be achieved even in the optical system where the optical path length is varied significantly.
Also, with the present invention, since the angle or angles of one or both of the first and second magnification varying mirrors by rotating the motor in the magnitude depending upon original reading magnification set in the operating portion, variation of number of times of turning of the reflected light depending upon the original reading magnification can be done easily.
With the present invention, since the image of the original is read by reciprocally moving the optical module including the first and second magnification varying mirrors, the optical lens and the linear image sensor, in the auxiliary direction after permitting setting of number of times of turning of the reflection light between the first and second magnification varying mirrors, the optical module can be further down-sized to contribute for down-sizing of the overall original reading apparatus.
With the present invention, since the optical lens is fixed and the linear image sensor side is moved by the linear image sensor moving means, the image of the reading position of the original can be accurately formed at the image reading position.
With the present invention, since the reading position adjusting means for adjusting the reading position in the auxiliary scanning direction by controlling rotation angle of the position adjusting reflection mirror, reading start position can be maintained constant even when magnification is differentiated. On the other hand, at the stage where a the optical module is set at home position as the original reading start position for example, it is also possible to read image information of the member for shading correction using the reading position adjusting means as required. Namely, advantage is accomplished to avoid necessity of varying control of the shifting position of the optical module between the case where the shading correction is performed and the case where the shading correction is not performed.
Also, with the present invention, since the reading position of the original is set at a position away from the surface position of the platen glass, focused image can be obtained even when the film holder is set on the platen glass or when a three-dimensional image, such as thick book or the like is to be read.
Furthermore, with the present invention, by deflecting the light reflected from the second magnification varying mirror in the longitudinal direction of the optical module using the optical path varying means, when the linear image sensor is small in certain extent, length of the optical module in the auxiliary scanning direction can be set shorter. As a result, the length of the original reading apparatus in auxiliary scanning direction can be shortened. On the other hand, by deflecting the light in parallel to the platen glass instead of downward direction of the platen glass perpendicular to the optical module, length of the optical module in this direction can be shortened to reduce thickness of the original reading apparatus.
Although the present invention has been illustrated and described with respect to exemplary embodiment thereof, it should be understood by those skilled in the art that the foregoing and various other changes, omission and additions may be made therein and thereto, without departing from the spirit and scope of the present invention. Therefore, the present invention should not be understood as limited to the specific embodiment set out above but to include all possible embodiments which can be embodied within a scope encompassed and equivalent thereof with respect to the feature set out in the appended claims. | An original reading apparatus can realize stepwise or sequential variable magnification using relatively small size optical system upon reading an original. The apparatus includes a first mirror arranged in an optical path from a reading position of an original to an image forming portion across an image forming lens and reflecting a light from the reading position of the original, and a second mirror arranged with placing a reflection surface in opposition to a reflection surface of the first mirror and reflecting a light reflected from the first mirror for a plurality of times between the first and second mirrors, and thereafter reflecting toward the image forming lens. A mirror angle positioner for varying an angle of the reflection surface of at least one of the first and second mirrors depending upon a designated original reading magnification. | 6 |
BACKGROUND OF THE INVENTION
1. Technical field
This invention is concerned with materials for nonlinear optical devices for the conversion of optical energy at one frequency to optical energy at another frequency.
2. Discussion of the prior art
Laser techniques have been developed so that it is possible to obtain a limited number of fundamental frequencies of coherent laser light by utilizing solid, gas, and liquid media. However, in many applications, laser light having frequencies not among the fundamental frequencies obtainable is required, and in some cases laser light exhibiting a continuous spectrum over a certain range of frequencies is required. Nonlinear optical crystals have, therefore, frequently been employed to convert coherent laser light of a fundamental frequency into laser light of the second harmonic, that is to say, laser light with a frequency twice the fundamental frequency.
In the prior art, monocrystalline forms of inorganic materials such as potassium dihydrogen phosphate (KDP), ammonium dihydrogen phosphate (ADP), barium sodium niobate (BaNaNbO3), and lithium niobate (LiNbO3) have been used for generating higher frequency harmonics. Monocrystalline KDP and ADP, while offering greater resistance to optical irradiation induced surface damage due to laser beam bombardment, do not exhibit large optical nonlinearities, thereby rendering these crystals unfavorable for higher harmonic frequency generation or conversion. In contrast, BaNaNbO 3 , and LiNbO 3 show large nonlinearities but, unfortunately, a low resistance to optical damage. In this regard, the term "resistance to optical damage" means the number of times the surface of a crystalline material can be bombarded (shots) with laser radiation of a given power density in watts per unit area before the subject crystal shows signs of opacity. Thus, a crystal showing high resistance can sustain a larger number of shots than a crystal of low resistance for the same power density of the incident laser beams.
Use of organic molecules in nonlinear optical devices has generated much interest recently because a large number of molecules are available for investigation. Some substituted aromatic molecules are known to exhibit large optical nonlinearities. The possibility of such an aromatic molecule having large optical nonlinearities is enhanced if the molecule has electron donor and acceptor groups bonded to the conjugated system of the molecule. The potential utility for very high frequency application of organic materials having large second-order and third-order nonlinearities is greater than that for conventional inorganic electro-optic materials because of the bandwidth limitations of inorganic materials. Furthermore, the properties of organic materials can be varied to optimize mechanical and thermo-oxidative stability and laser damage threshold.
U.S. Pat. No. 4,199,698 discloses that the nonlinear optical properties of 2-methyl-4-nitroaniline (MNA) make it a highly useful material in nonlinear devices that convert coherent optical radiation including a first frequency into coherent optical radiation including a second frequency. The nonlinear devices have means for introducing coherent radiation of a first frequency into the MNA and means for utilizing coherent radiation emitted from the MNA at a second frequency.
Diacetylenes and polymers formed from diacetylenic species, which are amenable to close geometric, steric, structural, and electronic control, provide nonlinear optic, waveguide, piezoelectric, and pyroelectric materials and devices. Diacetylenes which are crystallizable into crystals having a noncentrosymmetric unit cell may be elaborated into a thin film upon a substrate by the Langmuir-Blodgett technique. Such films may be polymerized either thermally or by irradiation for use in nonlinear optical systems. Diacetylenes are covalently bonded to substrates through the employment of silane species and subsequently polymerized to yield nonlinear optic devices having high structural integrity in addition to high efficiencies and optical effects. U.S. Patents relating to these acetylenic materials include U.S. Pat. Nos. 4,605,869 and 4,431,263.
U.S. patents relating to non-linear optical properties of organic materials include U.S. Pat. Nos. 4,208,501; 4,376,899; 4,579,915; and 4,607,095.
DESCRIPTION OF THE DRAWING
FIG. 1 is a diagrammatic representation of a device capable of generating coherent second harmonic light radiation with 5-chloro-2-nitroaniline.
SUMMARY OF THE INVENTION
The present invention provides a laser generator of coherent second harmonic light radiation by utilizing 5-chloro-2-nitroaniline and a method of generating coherent second harmonic light radiation with such a device.
In general, second harmonic generators of this invention comprise, in combination, a laser source of coherent light radiation at a fixed fundamental frequency, 5-chloro-2-nitroaniline as the second harmonic generator, a means for directing the output radiation of the laser onto the organic molecular crystalline 5-chloro-2-nitroaniline, and output means for utilizing the second harmonic frequency.
DETAILED DESCRIPTION
5-Chloro-2-nitroaniline suitable for use in the present invention is crystalline in form, and is preferably in solid crystalline form. Three crystal structures or polymorphs have been identified by X-ray powder diffraction. One crystal structure of 5-chloro-2-nitroaniline that has been found to exhibit second harmonic generation shows it to belong to the noncentrosymmetric space group Pna2 1 , i.e. it crystallizes in a noncentrosymmetric configuration (see Stout, G. H. and Jensen, L. H., "X-Ray Structure Determination," Macmillan Publishing Co., Inc.: 1968, for a discussion on crystal structure analysis). Non-centrosymmetric species are those which have no center of symmetry on either the molecular or crystalline unit cell level.
5-Chloro-2-nitroaniline is substantially transparent to electromagnetic radiation having wavelengths from 400-500 nm to 1000-1100 nm. Accordingly, the compound is useful in second harmonic generators wherein both incident radiation and emergent radiation range from 500 nm to 1064 nm.
5-Chloro-2-nitroaniline is commercially available from Aldrich Chemical Co., Inc., Milwaukee, WI. However, the commercial material is generally not the active form thereof, and it must be recrystallized from ethanol to obtain the form which exhibits second harmonic generation. Alternatively, 5-chloro-2-nitroaniline can be synthesized by the acylation and nitration of 3-chloroaniline, followed by hydrolysis and separation of the resultant chloronitroaniline isomers, 5-chloro-2-nitroaniline and 3-chloro-4-nitroaniline following an acylation, nitration, and hydrolysis scheme similar to that described in Howard, J. C., Org. Syn., IV 1963, 42-45.
Devices that are capable of generating coherent second harmonic light radiation with 5-chloro-2-nitroaniline described herein are well known in the art. Representative examples of such devices are described in U.S. Pat. Nos. 3,395,329; 3,431,484; and 3,858,124; and U.S. patent application Ser. Nos. 925,300 (now U.S. Pat. No. 4,714,838) and 937,234; all of which are incorporated herein by reference for the purpose of describing devices which can incorporate the 5-chloro-2-nitroaniline described herein and exhibit second harmonic generation.
Advantages of this invention are further illustrated by the following examples, but the particular materials and amounts thereof recited in these examples, as well as other conditions and details, should not be construed to unduly limit this invention.
Parts and percentages are by weight unless otherwise indicated. All of the compounds prepared in the examples and comparative examples were characterized by conventional analytical techniques, e.g. infrared spectroscopy, ultraviolet/visible absorption spectroscopy, nuclear magnetic resonance spectroscopy, melting point, elemental analysis, X-ray powder diffraction and X-ray diffraction single crystal measurements.
Crystals were evaluated for second harmonic generation efficiency using the second harmonic generation (SHG) powder test described in Kurtz et al., J. Appl. Phys. 1968, 39, 3798. The sample was ground and sieved and then mixed with a liquid of chosen refractive index to minimize beam scatter caused by the differences in the index of refraction between the particles and the ambient atmosphere (index-matching). The index-matched sample was placed between cell flats spaced 0.35±0.02 mm apart. Particles having mean diameters greater than 90 micrometers but less than 180 micrometers were used. The particles of optimum size were obtained by sieving through appropriate mesh screens. Each sample was mixed with a drop of index matching fluid having a refractive index of 1.63 (R. P. Cargille, Cedar Grove, N.J.). The samples were not index matched critically, so that the actual SHG efficiencies may be higher than that reported in the example.
Referring now to FIG. 1, infrared radiation at 1064 nm from a Q-switched Nd-YAG laser 10 was weakly focused onto cell 12 containing the prepared sample. In the device illustrated in FIg. 1, the means for directing the output radiation of the laser, e.g. a lens, first through a filter 14 (Corning CS2-60 color filter used to block any radiation at 532 nm) and then onto cell 12 containing the 5-chloro-2-nitroaniline containing sample was integrated into the laser 10 and is not shown as a separate component. Means for directing the output radiation of the laser onto the organic molecular crystalline compound are well-known to one of ordinary skill in the art. An infrared blocking filter 16 placed behind the sample allowed only the second harmonic frequency generation to pass through a 1/3 meter monochrometer 18 tuned at 532 nm. Output of the monochrometer 18 was directed to a photomultiplier tube 20, and the resulting signal was processed by a boxcar averager 22 that averages signals over many laser pulses.
Urea was the chosen standard because of its high second order coefficient and its availability. The urea standard was prepared in the same manner as the samples. The urea standard was indexed matched reasonably well with the index matching fluid, with a mismatch of about 0.01. The reported efficiency of a sample is its SHG signal normalized to that of the urea standard measured under the same experimental conditions.
EXAMPLES
Example 1
A mixture containing 125 ml of 3-chloroaniline and 500 ml of glacial acetic acid was refluxed for 4 hours. After the mixture was cooled to 95° C., 600 ml of water was added to precipitate the crude 3-chloroacetanilide. The 3-chloroacetanilide crystals were collected by filtration and then refluxed in 550 ml of toluene. After the water was removed as an azeotrope with toluene through the use of a Dean Stark water trap, 550 ml of cyclohexane was added to precipitate 3-chloroacetanilide, which was then filtered, collected and dried (see Beilstein, F. and Kurbatow, S., Annalen 1876, 182, 94).
To a mixture containing 30 ml of glacial acetic acid and 55 ml of concentrated sulfuric acid maintained at 10° C. with stirring were added 33 g of 3-chloroacetanilide in one portion and 20 ml of fuming nitric acid from a dropping funnel. The resulting mixture was poured over ice and a precipitate containing the isomers 5-chloro-2-nitroacetanilide and 3-chloro-4-nitroacetanilide was filtered, collected, and dried in a vacuum oven (see Mayes, H. A. and Turner, E. E., J. Chem. Soc. 1928, 691).
Hydrolysis of the isomeric chloroacetanilides was carried out by adding the mixtures collected in the previous step to 60% sulfuric acid and maintaining the temperature at 100° C. for 1 hour. The resultant solution was added to an excess of water to precipitate a product consisting of the isomers 5-chloro-2-nitroaniline and 3-chloro-4-nitroaniline (see Mayes, H. A. and Turner, E. E., J. Chem. Soc. 1928, 691).
The isomers from the previous step were separated by extraction with two 80 ml portions of chloroform. The 5-chloro-2-nitroaniline, which was more soluble, was recovered from the chloroform solution by evaporation of the chloroform, and the residue recrystallized several times from ethanol to give a product which exhibited second harmonic generation.
Sieved particles of 5-chloro-2-nitroaniline having diameters between 90 and 180 micrometers were mixed with an index-matching fluid having a refractive index of 1.63 and placed between cell flats spaced 0.35±0.02 mm apart to determine the SHG efficiency.
Second harmonic generation measurements of 5-chloro-2-nitroaniline show an efficiency value of 20 relative to urea.
The crystal structure of the active form of 5-chloro-2-nitroaniline was determined using a ENRAF-NONIUS (Bohemia, N.Y.) CAD4 Automatic diffractometer with Mo K-alpha radiation.
COMPARATIVE EXAMPLES
The compounds listed below in Table I were prepared in substantially the same manner as was the compound of Example 1. The compounds were recrystallized from ethanol. The compounds were evaluated for SHG in the same manner as was the compound of Example 1.
TABLE I______________________________________Example no. Compound SHG efficiency______________________________________1 5-chloro-2-nitroaniline 20A (comp.) 5-chloro-4-nitroaniline ≦0.001B (comp.) 5-nitro-2-chloroaniline ≦0.001C (comp.) 4-nitro-2-chloroaniline 2D (comp.) 4-chloro-2-nitroaniline 0.03E (comp.) 4-chloro-3-nitroaniline ≦0.001F (comp.) 5-bromo-2-nitroaniline ≦0.001G (comp.) 5-fluoro-2-nitroaniline ≦0.001H (comp.) 5-trifluoromethyl-2-nitroaniline ≦0.001______________________________________
The data in the foregoing table show that of numerous species of anilines containing both nitro (--NO 2 ) and halo (--F, --Cl, --Br) or halo-substituted alkyl substituents, only the 5-chloro-2-nitroaniline species demonstrates an unexpectedly high SHG efficiency.
Various modifications and alterations of this invention will become apparent to those skilled in the art without departing from the scope and spirit of this invention, and it should be understood that this invention is not to be unduly limited to the illustrative embodiments set forth herein. | Devices for and method of generating coherent second harmonic light radiation. The devices comprise a laser source of coherent light radiation at a fixed fundamental frequency, crystalline 5-chloro-2-nitroaniline that crystallizes in a non-centrosymmetric configuration, means for directing the output radiation of the laser onto the 5-chloro-2-nitroanilane, and output means for utilizing the second harmonic frequency. | 6 |
This is a divisional of application Ser. No. 801,915, filed May 31, 1977, which, in turn, is a continuation-in-part of application Ser. No. 502,095, filed Aug. 30, 1974, which is abandoned.
FIELD OF THE INVENTION
This invention relates to compounds exhibiting photochromism and useful applications of compounds having this property.
DESCRIPTION OF THE PRIOR ART
Photochromism can be defined as the ability of a material to reversibly change its visible absorption spectrum on exposure to activating radiation and to revert to its original absorption spectrum on removal of the activating radiation or on substituting radiation of a different wavelength.
Organic photochromic compounds have been known for over a hundred years but they excited little commercial interest until the 1950's. In 1955 Y. Hirschberg (J.A.C.S. volume 78, page 2304-2312) investigated three photochromic spiropyrans and one bianthrone derivative which produced coloured forms on exposure to U.V. light and returned to their colourless state on exposure to visible light. Hirschberg measured the rate of formation of the coloured species and vice-versa in various media and concluded that none of the tested compounds would be suitable for the purpose he had in mind, namely date storage, because the rate of colour formation and the rate of bleaching was insufficiently rapid. A further problem encountered by Hirschberg and many subsequent investigators is that the coloured forms tend to be unstable at temperatures approaching normal ambient so that for many compounds the photochromic phenomenon can only be satisfactorily observed at temperatures in the region of -60° C. or below. This obviously makes them unsuitable for practical use in commercial applications. In the search for commercially suitable photochromic compounds, one class of compounds which have been investigated by various workers are derivatives of bismethylene succinic anhydride, which are commonly referred to in the art as "fulgides". These were first described by Stobbe (Chem.Ber. 1904, 37 2236) who discovered a general procedure for their preparation which is still a commonly used process.
Santiago and Becker (J.A.C.S. 1968 90 page 2654) suggested that the primary process by which fulgides form coloured species is a photocyclisation but recognised that competing reactions occurred in the compounds tested. Specific fulgides and related compounds have also been prepared by El-Assal and Shehab (J.Chem. Soc. 1963 pages 3478-82), Brunow et al (Acta.Chem. Scand. 22, 1968, pages 590-5) and by Heller in British Patent No. 1,271,655, but the fulgides described by these workers all show comparatively poor photochromic properties and exhibit irreversible side reactions commonly known as fatique and poor thermal stability. Fatigue products affect the photochromic properties and the properties deteriorate progressively with every colour/erase cycle.
SUMMARY OF THE INVENTION
The present invention is based on a clearer understanding of the mechanism involved in the reversible formation of the coloured products and development of compounds which have a reduced tendency to undergo irreversible side reactions and which also exhibit improved thermal stability.
As a result of this work I have now discovered a series of substituted phenyl methylene succinic anhydrides and succinic imides having markedly improved photochromic properties. The photochromic compounds encompassed by the present invention have the general formula: ##STR2## wherein X represents oxygen or NR 6 , R 6 being hydrogen alkyl, aryl or aralkyl.
R 1 represents hydrogen, alkyl, aryl or aralkyl,
Y and Y 1 are the same or different and represent hydrogen, alkyl, halogen or alkoxy,
Z represents hydrogen, halogen, alkyl, alkoxy or aryloxy,
R 5 represents hydrogen, alkyl, alkoxy or aryloxy,
R 4 represents alkyl or aryl, and
R 2 and R 3 represent the same or different alkyl, aralkyl or aryl groups or one of R 2 and R 3 represents hydrogen and the other is alkyl, aralkyl or aryl,
with the proviso that when Z or Y is alkoxy or aryloxy, R 1 is other than hydrogen.
The aryl groups in the above general formula particularly those at R 1 , R 2 , R 3 or R 6 , may be substituted e.g. by halogen, alkyl having 1 to 20 carbon atoms, cycloalkyl having 3 to 12 carbon atoms, aralkyl having 7 to 12 carbon atoms, alkoxy having 1 to 20 carbon atoms or alkaryl groups having 7 to 22 carbon atoms or any combination thereof.
Typical unsubstituted aryl groups are phenyl or naphthyl. Examples of substituted aryl groups are dimethoxyphenyl, piperonyl, methylphenyl, ethylphenyl, isopropylphenyl, t-butylphenyl, sec-butylphenyl, amylphenyl, n-dodecylphenyl and 2,4-dimethylphenyl. Examples of aralkyl groups are benzyl, α-methyl benzyl and α, α-dimethyl-benzyl and examples of suitable cycloalkyl groups are cyclopentyl and cyclohexyl.
DETAILED DESCRIPTION OF THE INVENTION
In the general formula (1) above, where X is oxygen, the compounds are derivatives of succinic anhydride and are conveniently referred to as "fulgides". The corresponding succinic imides (where X=>NR 6 ) are similarly referred to in this specification as "fulgimides".
Compounds of the general formula (1) will on exposure to activating radiation, such as U.V. light, undergo photocylisation to the corresponding naphthalene derivative having the following structural formula (2) below: ##STR3##
The naphthalene derivatives of general formula (2) are resonance stabilised, having a canonical form shown in structural formula (3). It is the series of conjugated double bonds, in the structure shown in formula (3), extending from the ═O + R 4 group to the --O - moiety which is thought to be responsible for the coloured properties of the compounds.
Referring to the numbering in the structural formula (1) the presence of the alkoxy or aryloxy group in the 8 position activates the ring towards electrophilic attack in the positions ortho and para to it, thus facilitating ring closure at these positions. A second alkoxy or aryloxy substituent at the 6 position (i.e. R 5 ) reinforces the activation at the position ortho or OR 4 and para to R 5 . Consequently compounds having alkoxy or aryloxy substituents in both the 6 and 8 positions show a more facile photochemical conversion into the coloured form.
Whereas compounds in which alkoxy or aryloxy substituents are present in both the 6 and 8 positions exhibit pronounced photochromism on exposure to activating radiation, such properties are in general only exhibited in compounds having a 7 or 5 alkoxy or aryloxy substituent when R 1 is the structural formula (1) in an alkyl or aryl group.
The reason for this is thought to be that when R 1 is hydrogen, cis-trans isomerism is the favoured reaction rather than cyclisation; for example the main reaction on exposing compound (4) below to U.V. light is formation of an isomer via the excited state of having structure (5) below ##STR4##
Compounds of formula (4) are generally non-photochromic or only weakly photochromic. Surprisingly it is found that when R 1 is alkyl or aryl (especially a bulky group such as methyl) the cyclisation reaction to compounds of the general formula (2) is again favoured, probably because steric hindrance between the R 1 group and the carbonyl groups inhibits coplanarity in the structure.
In compounds of the invention where no alkoxy or aryloxy group is present in the 6 position, it is preferred that the Y position is other than hydrogen since this position is thereby blocked and ring closure in this position is prevented. Otherwise the yield of photochromically active compounds is reduced.
The term "photochromism" is used in the specification to denote a colour change. Such change may be from one coloured form to a differently coloured form or from a colourless form to a coloured form. The term also includes changes which are in intensity or depth of colour rather than from one distinct colour to another.
Provided that the moieties represented by --OR 4 , R 5 and R 1 have the identities discussed above, the nature of the remaining substituents can be varied widely within the types of radicals indicated and photochromic compounds obtained which have improved thermal stability and are much less subject to fatique when compared with compounds described in the prior art.
The improved phtochromic properties of the compounds in accordance with the invention makes them suitable for a wide variety of practical applications as photochromic compositions or devices. The commercial applications of the compounds fall into two broad classes (1) those in which a temporary image is formed and (2) those in which use is made of the reduced transmission or reflection of light by the coloured forms.
In the first group of applications the photochromic compounds can be used with advantage in various reproduction, copying and information display systems. Specific examples are as follows.
PHOTOGRAPHY AND REPRODUCTION SYSTEMS
Films or plates may be prepared by coating a support with a solution, dispersion or emulsion containing a compound or mixture of compounds in accordance with the invention. The resulting films or plates can be used as temporary positives or negatives without any need for development or fixing from which permanent prints can be made using conventional photographic materials. The image can be erased and the same photochromic film or plate re-used repeatedly.
Reproduction and copying using plates or films are of particular value in making temporary copies e.g. from microfiche or to prepare a temporary master which can be examined and corrected before a final permanent copy is made.
Information transfer systems are another field in which the compounds of the invention may be used. Government and other organisations often mark classified information in red. Telecopier devices using helium, neon or other red light emitting lasers cannot detect information written in red and photography or other permanent copying of such information is restricted. A temporary copy can be made on a screen bearing a photochromic compound having a bluish coloured form, the information can then be transmitted from the temporary copy and the image erased immediately after use leaving no trace of the classified information and the screen can be re-used many thousands of times.
PHOTOCHROMIC DISPLAY SYSTEMS
Photochromic screens can also be used as information boards, e.g. at railway stations or airports or in special display systems such as flight simulators. The information can be written on the boards with a scanning laser or other light beam device and subsequently erased or updated.
The formation of the coloured cyclic structure is stimulated most effectively by exposure of the compounds to light in the near ultra-violet range, e.g. at about 330-400 mm. On removal of the activating radiation, the compounds will revert to the non-coloured or less coloured form but at normal ambient temperatures the change is not instantaneous. The rate will depend upon the temperature (the higher the temperature, the greater the rate of reversion) and the nature of the substituents. For example, alkoxy substituents in the 6 and 8 positions will increase the half-life of the coloured form, as will the presence of an alkyl or aryl substituent at R 1 and alkyl or aryl groups at both R 2 and R 3 . For most of the applications described above it will be necessary or desirable to remove the image at a faster rate than the natural fading rate and this is readily achieved by exposure to a light in the visible spectrum, preferably green light in the range of about 514-550 mm, which can be obtained using an argon ion laser.
The second group of applications make use of the reduced light transmission properties of the coloured forms of the compounds. Thus photochromic packaging film (e.g. coated cellophane) can be used as an outer wrapper to protect products from the effects of sunlight, while allowing the products to be viewed through the wrapping in artificial light. Perishable foodstuffs and pharmaceuticals are examples of products which may be advantageously protected in this way.
Similarly shop windows or storage cabinets may be treated with the compounds of the invention so as to protect their contents. Paints can be formulated with the photochromic compounds so as to reduce the penetration of sunlight, thereby reducing dazzle, extending the life of the paint film or providing camouflage for the military.
For the above uses, the photochromic compounds are normally dispersed in a light transmissive vehicle to form a solution, emulsion or dispersion and then applied as a coating to a support, after which the coninuous phase is removed. Alternatively the compounds may be incorporated within or impregnated into a support, which may be a plate, film, fabric, paper or sheet. Further alternative presentations are as a solid polycrystallite coating, as a large single crystal or as a fluid solution in a cell.
Photochromic compounds in accordance with the invention wherein alkoxy or aryloxy substituents are present in both the 6 and 8 positions form a preferred sub-class of photochromic compounds. In such compounds the substituents in the 6 and 8 positions act as auxochromic groups giving rise to strong absorbtion in 500 to 600 mm waveband and typical maxima at about 550 mm. This gives the coloured forms a deep purple to dark blue appearance. Additional thermal stability is also observed with compounds of this sub-class, which is thought to arise from resonance between the excited state indicated in formula (3) above and a similar structure in which the positive charge falls on the alkoxy or aryloxy group in the 6-position.
Because of ease of preparation using available starting materials, compounds in which the 6 and 8 substituents are both alkoxy are preferred to the corresponding compounds in which the substituents are aryloxy groups. Preferably the alkoxy groups are lower alkoxy (1 to 5 carbon atoms), methoxy being especially preferred.
The alkyl or aryl groups represented by R 2 and R 3 may be varied widely but preferably are lower alkyl (1 to 5 carbon atoms).
Examples of specific compounds falling within the scope of the present invention are as follows: ##STR5##
The compounds of the present invention can be prepared by condensing an aldehyde or ketone of the formula (6) ##STR6## with an ester of a succinic acid derivative of the formula (7) ##STR7## wherein R 1 , R 2 , R 3 , R 4 , R 5 , Y, Y 1 and Z are as defined above and R 7 is the residue of an alcohol, by a Stobbe condensation, hydrolysing the half ester produced to form the di-acid, and then heating the resulting di-acid with an acid chloride to give a product of formula (1) wherein X is oxygen.
The Stobbe condensation is carried out by refluxing the reactants in t-butanol containing potassium t-butoxide if vigorous conditions are required, or with sodium hydride in anhydrous ether if mild reaction conditions are needed. Preferably potassium t-butoxide in t-butanol is used. The product of this stage of the reaction is the half ester, i.e. where one R 7 group is hydrogen. This is then converted into the di-acid by hydrolysis, e.g. by boiling with aqueous potassium hydroxide solution. The di-acid is then converted into its anhydride by a dehydration reaction comprising heating with an acid chloride. Preferably acetyl chloride is used.
The compounds of formula (1) produced in this way in which X is oxygen can be converted into those where X is >NR 6 by heating equimolar proportions of the anhydride and the primary amine R 6 NH 2 to produce the corresponding half amide. The half amide is then converted into the desired compound by heating with an acid chloride or acid anhydride such as acetyl chloride or acetic anhydride. The reaction with the amine may be carried out in an organic solvent if desired, e.g. ethanol or benzene.
An alternative method of preparing compounds of formula 1 in which X is >NR 6 is to react the half ester product of the Stobbe condensation with a compound of the formula
R.sub.6 NHMgBr
to produce the corresponding succinamic acid, i.e. wherein the group --COOR 7 becomes --CONHR 6 . This is then dehydrated by reaction with an acid chloride such as acetyl chloride.
The Stobbe condensation is a procedure of general application for the synthesis of fulgides in accordance with the invention as well as starting materials of formula (7). A fairly comprehensive account of the Stobbe condensation and its application to the synthesis of succinic acid derivative can be found in Chapter 1 of volume 6 of "Organic Reactions" published by Wiley, New York, 1951, pages 1 to 73.
Fulgimides in which R 6 is hydrogen may be prepared by reacting the appropriate succinic anhydride with concentrated ammonia to produce the corresponding half amide acid and then reacting the product with diazomethane to yield the methyl ester of the half amide, followed by cyclisation using sodium ethoxide. This procedure is fully described in the paper by Goldschmidt et al, published in Liebigs Annalen der Chemie, 1957, volume 604, pages 121 to 132.
The invention will be illustrated with reference to the following Examples in which parts are parts by weight unless otherwise indicated.
EXAMPLE 1
Preparation of (E)-3,5-dimethoxybenzylidene isopropylidenesuccinic anhydride.
3,4-dimethoxybenzaldehyde (7.8 parts) and diethyl isopropylidenesuccinate (10 parts) were added to a boiling solution of potassium t-butoxide (5 parts) in t-butanol (70 parts by volume). After 10 minutes, the reaction mixture was cooled, the solvent removed and the residual oil acidified with hydrochloric acid. The liberated (E)-3,5-dimethoxybenzylidene isopropylidenesuccinic half ester was recrystallised from ethanol, m.p. 109°-110° C.
The half-ester (3 parts) was hydrolysed by boiling with 5% aqueous potassium hydroxide solution and the diacid precipitated by the addition of hydrochloric acid. The dried diacid was dissolved in acetyl chloride (100 parts by volume), boiled for 1 hour and the solvent removed. The residual oil was crystallised from benzene/petrol mixture to give (E)-3,5-dimethoxybenzylidene isopropylidenesuccinic anhydride (1.6 parts) in the form of yellow needles, m.p. 161°-162° C., which on irradiation at 366 nm, turn blue. The colour is reversed on exposure to white light.
By condensing the appropriate substituted succinic ester with 3,5-dimethoxybenzaldehyde, according to the above procedure the following compounds were prepared:
(E)-3,5-dimethoxybenzylidene (E)-2-butylidenesuccinic anhydride
(E)-3,5-dimethoxybenzylidene (Z)-2-butylidenesuccinic anhydride
(E)-3,5,dimethoxybenzylidene (E)-isobutylidenesuccinic anhydride
EXAMPLE 2
(E)-3,5-dimethoxybenzylidene isopropylidene-succinic half ester (3 parts), prepared as in Example 1, in ether was added to an excess of anilinomagnesium bromide in ether, and the reaction mixture boiled for 15 minutes, cooled and acidified with hydrochloric acid. The liberated succinamic acid was filtered off and recrystallised from ethanol. The dry acid was dissolved in acetyl chloride (100 parts by volume) boiled for 1 hour and the solvent removed. Crystallisation of the product from a benzene/petrol mixture gave (E)-3,5-dimethoxybenzylidene isopropylidene-N-phenylsuccinimide as yellow needles, m.p. 168°-169° C. The compound shows similar photochromic properties to the corresponding anhydride.
EXAMPLE 3
Preparation of (E) and (Z)-α-(3,4,5-trimethoxyphenyl) ethylidene-isopropylidenesuccinic anhydrides.
3,4,5-trimethoxyacetophenone (5 parts) and diethyl isopropylidenesuccinate (5 parts) were added to a boiling solution of potassium t-butoxide (2.8 parts) in t-butanol. Work up by the method described in Example 1 gave the half ester which was hydrolysed to the diacid (2.7 parts) with 5% aqueous potassium hydroxide solution followed by acidification with hydrochloric acid. The di-acid was dried and heated for 1 hour with acetyl chloride (20 parts by volume) and the solvent removed. Recrystallisation of the residual oil from benzene/petrol gave (E)-α-(3,4,5-trimethoxypenyl)-ethylidene isopropylidenesuccinic anhydride as pale yellow cubes, m.p. 139°-140° C., which turn deep blue on irradiation at 366 nm. The colour is reversed with white light.
The (Z) isomer was obtained in a later crop of crystals, which on irradiation at 366 nm. photoisomerise to the (E) isomer which shows photochromic properties. (E)-α-(3,5-dimethoxyphenyl) ethylidene isopropylidenesuccinic anhydride was obtained in an analogous reaction starting from 3,5-dimethoxyacetophenone.
EXAMPLE 4
(E)-α-(3,4,5-trimethoxyphenyl) ethylideneisopropylidene succinic anhydride (4 parts), prepared as in Example 3, in toluene (40 parts by volume), and aniline (1 part) were heated (12 hours) at 70°. Petrol was added and the liberated succinamic acid separated. The dry acid (1.8 parts) was dissolved in acetyl chloride (40 parts by volume) boiled for 2 hours and the solvent removed. Crystallisation of the product from a toluene/petrol mixture gave (E)-α-(3,4,5-trimethoxyphenyl) ethylideneisopropylidene-N-phenylsuccinimide as pale yellow needles, melting point 169.5°. The compound shows similar photochromic properties to the corresponding (E)-anhydride.
EXAMPLE 5
Preparation of (E)- and (Z)-α-3,5-dimethoxyphenylethylidene (isopropylidene) succinic anhydrides.
3,5-dimethoxyacetophenone (4.2 parts) and diethyl isopropylidene succinate (4.9 parts) in benzene (20 parts by volume) were added to a stirred suspension of sodium hydride (1 part) in benzene (100 parts by volume). When reaction was complete, a small amount of ethanol was added to destroy excess sodium hydride, the solvent was removed, and the residual oil acidified with hydrochloric acid. The resulting half ester (5 parts) was hydrolysed with 2% ethanolic potassium hydroxide solution and the diacid precipitated by addition of hydrochloric acid. The dried acid (3.5 parts) was boiled with acetyl chloride (50 parts by volume) for 1 hour and the solvent removed. The (E)- and (Z)-anhydrides were separated by fractional crystallisation from toluene and light petroleum giving pale yellow crystals, m.p. 146°-147° and 124°-126°, respectively, which on irradiation at 366 nm turn blue. The colour is reversed on exposure to while light.
(E,E)-Benzylidene-α3,4,5-trimethoxyphenylethylidenesuccinic anhydride can be prepared by a similar procedure using 3,4,5-trimethoxyacetophenone and diethyl (E)-benzylidene succinate as reactants. The anhydride is obtained as yellow cubes, m.p. 181° which show similar photochromic properties.
The following Examples are given to illustrate the production of photochromic films and screens in accordance with the invention.
EXAMPLE 6
10 grams of the pale yellow crystals obtained in Example 3 were dissolved, together with 100 grams of cellulose acetate, in 1 liter of a 50/50 volume mixture of 2-hydroxy ethyl acetate and acetone. The resulting solution was filtered and coated onto a cellulose acetate base sheet using a blade over roller coating technique to achieve a wet coating thickness of 120 microns. After drying at 120° C., the coating had a dry thickness of about 12 microns. The resulting screen produced a deep blue image when exposed to a light beam having a wavelength of 366 nm, the image being extinguished by subsequent exposure to a light beam at 550 nm and could be used as a display screen. Screens of higher optical quality can be produced using glass plates in place of cellulose acetate film.
EXAMPLE 7
A solution containing 10 grams of the crystals obtained in Example 1 were dissolved in 1 liter of toluene with warming. A piece of "Wratten" 50 grade paper was dipped into the solution, removed and dried in air at room temperature. A blue image was obtained by exposing the impregnated paper to light of wavelength 366 nm and, the impregnated paper was suitable for making temporary copies e.g. from microfiche, under normal ambient temperatures. | Photochromic compounds and useful applications thereof having the general formula: ##STR1## in which X represents oxygen or NR 6 , R 6 being hydrogen, alkyl, aryl or aralkyl, R 1 represents hydrogen, alkyl, aryl, or aralkyl, Y and Y 1 being the same or different represent hydrogen, alkyl, halogen, or alkoxy, Z represents hydrogen, halogen, alkyl, alkoxy, or aryloxy R 5 represents hydrogen, alkyl, alkoxy, or aryloxy, R 4 represents alkyl or aryl, and R 2 and R 3 represent the same or different alkyl, aralkyl or aryl groups or one of R 2 and R 3 represents hydrogen and the other is alkyl, aralkyl, or aryl, and with the proviso that when Z or Y is alkoxy or aryloxy, R 1 is other than hydrogen. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a method for opening and mixing fiber bales in accordance with predetermined proportions in the mixture, wherein the fiber material is removed from the bales by being taken off in individual amounts and the amount removed is measured, and apparatus for carrying out the method.
It is known for fiber material to be removed from bales by being taken off in individual amounts by means of a gripper device for the purposes of putting together fiber mixtures with predetermined proportions therein. The amounts of fibers which are removed from the bales in accordance with the relationship between the constituents of the mixture are collected and measured in an intermediate container which is in the form of a weighing device (U.S. Pat. No. 3,577,599).
In order to achieve a high production output, with the maximum accuracy in regard to maintaining the predetermined proportions in the mixture even when, on the one hand, very small amounts and, on the other hand, amounts which are large in relation thereto have to be taken from the bales to be mixed for the purposes of forming a mixture from different amounts of fibers, it has already been proposed that the amount of fiber which is taken from the bale in each gripping operation should be adapted to the magnitude of the respective constituent of the mixture. Adjustable limit means are associated with the drive arrangement of the gripper for controlling the ratio of the fibers removed from the bales. The limit switch means determines the width that the gripper means is opened and is actuated by a control device which determines the proportions of the constituents of the mixture (U.S. Pat. No. 4,107,820).
This arrangement makes it possible to operate, in the individual fiber supply stations which contain the respective constituents of the mixture, in accordance with the magnitude of the respective proportions to be supplied thereby with the gripper means set to a width of opening which is adapted to the respective constituent of the mixture. By adjustment of the limit means, the gripper means is set to a wide width of opening when dealing with fiber which forms a large proportion of the mixture while the gripper means is set to a small width of opening when dealing with a small constituent. If there is a plurality of fiber supply stations and if such stations are required to supply different amounts of fiber to form the respective proportions of the mixture, the number of limit means corresponds to the number of constituents of the mixture or fiber supply stations so that each fiber supply station has associated therewith a different width of opening of the gripper device which is adapted to the respective constituent of the mixture at that station. As an alternative, in accordance with the known proposal, the width of opening can be limited to two widths if there is considerable difference only between the constituents at two fiber supply stations while if there are other constituents, those other constituents are close to the above-mentioned two constituents. This system, however, also retains the principle of operating with a wide width of opening in relation to a fiber supply station with a constituent forming a large proportion of the mixture, and with a small width of opening when operating at a fiber supply station giving a constituent forming a small proportion of the mixture.
However, with this mode of operation, it may occur that when removing large amounts of fiber with the gripper means set to a correspondingly wide width of opening at a fiber supply station, a large amount of fiber may again be taken from a bale although the constituent of the mixture has almost reached its desired weight. In this case, the actual weight of the constituent will exceed the desired weight to an inadmissible extent.
SUMMARY OF THE INVENTION
The problem of the present invention is further to enhance the degree of accuracy in observing the predetermined proportions of the mixture while maintaining a high production output.
According to the invention, this problem is solved in that an initial weight is first associated with each constituent of the mixture and that, when the desired weight of the constituent, less the initial weight, is reached, the amount of fiber taken from the bale is reduced until the desired weight is reached, whereupon the amount of fiber taken from the bale is increased again at the beginning of the operation of removing the next constituent of the mixture.
The apparatus for carrying out the method comprising a tongs-like gripper means which presses into the fiber bales, a measuring means and a control means for determining the width of opening of the gripper means. The control means establishes the desired weight of a constituent of the mixture, less an initial weight, and when said weight is reached, switches the wide width of opening of the gripper means over to a small width of opening.
The construction designed to carry out the invention will be hereinafter described, together with other features thereof.
The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawing(s) forming a part thereof, wherein an example of the invention is shown and wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a view from the front of an apparatus for opening fiber bales having a gripper means;
FIG. 2 shows a view on an enlarged scale of a sensor;
FIG. 3 shows a plan view of the FIG. 1 apparatus, which is movable along a row of bales;
FIG. 4 shows a view from the front of the gripper means with drive means and associated limit means;
FIG. 5 shows a circuit diagram with control means; and
FIG. 6 shows a block circuit diagram of the control device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A column-like carrier 11 which is secured to a carriage 1 carries a gripper arm 2 with gripper fingers 21 which are arranged in pairs and which are generally denoted as gripping means 20 and which, as will be described in greater detail hereinafter, are opened and closed with a tongs-like movement (FIG. 1). The gripper arm 2 is movable in a vertical direction so that the gripping means 20 can be brought into engagement with a bale B and lifted away therefrom again. The vertical movement of the gripper arm 2 with the gripping means 20 is produced by way of a traction means, for example, a chain 3 which is secured to the gripper arm 2 and which is guided over guide rollers 30 and 31. A chain wheel 32 secured to a piston rod 33 engages the chain 3. The piston of the piston rod 33 is slidable in a cylinder 34 and is actuated pneumatically or hydraulically. The other end of the chain 3 is secured to a housing 35 which is displaced by the presence of a spring 36 on a rod 37 when the tension in the chain 3 is relaxed when the gripping means 20 penetrates into the fiber bale B (FIG. 3). The rod 37 is fixed on the column-like carrier 11. A switch SE which is displaceable in a vertical direction is arranged stationarily in the vicinity of the housing 35 which has a metal base 38. Sensing means of this kind for determining the depth of penetration of the gripping means into the bale by way of the chain tension are known in different forms so that the present form is shown only by way of example.
The removal device is movable along a row of fiber bales B1, B2, . . . B16 on rails 12 (FIG. 3). It is driven by a reversible traction motor M having a drive shaft 13 on which a chain wheel 14 is secured. The chain wheel 14 engages into a chain 15 which runs parallel to the rails 12. In the present example, the fiber bales B1, B2 . . . B16 form four fiber supply stations I, II, III and IV, each of the fiber supply stations containing a given kind of fiber, which fibers are to be mixed in predetermined proportions. The respective quantities of fiber corresponding to the above-mentioned proportions of the mixture are removed successively from the individual fiber supply stations I, II, III and IV by means of the gripping means 20 in known manner in accordance with a predetermined program, and dropped into a receiving container 16 which is secured to the column-like carrier 11 and which is in the form of a weighing device. For this purpose, the gripper arm 2 with the gripping means 20 is pivotal from a position above the fiber bales to a position above the receiving container 16.
The tongs-like opening and closing movements of the gripper fingers 21 forming the gripping means 20 are produced as shown in FIG. 4, by a piston rod 4 whose piston 40 is slidable in a cylinder 41 and is actuated pneumatically or possibly also hydraulically. The connection between this actuating arrangement which is disposed in the gripper arm 2, and the gripping means 20, is such that the piston rod 4 engages a rod 42 on which bars 43 and 44 are disposed. The bars 43 and 44 are pivotally connected to the gripper fingers 21 which, in turn, are mounted pivotally about an axis member 45 which is secured to the gripper arm 2 and which extends over the length thereof. Compressed air is supplied to the cylinder 41 alternately through two conduits 50 and 51 and is controlled by an electromagnetic valve 5 with solenoids 52 and 53. The valve 5 is connected to a compressed air source (not shown) by way of a conduit 54. Conduits 55 and 56 lead from the electromagnetic valve 5 into the open air.
The actuating device for opening and closing the gripping means 20 or the gripper fingers 21, in the present case being the piston rod 4, has associated therewith a stationary limit stop 68 and a limit swtch S1, which limit the downward movement of the piston rod 4 and thus determine the width of opening of the gripping means 20 or the gripper fingers 21. The limit stop 68, against which a sensing stop 47 secured to the piston rod 4 comes to bear in the course of the downward movement of the piston rod 4, provides for establishing a wide width of opening of the gripping means 20 and the limit switch S1 provides for establishing a small width. The limit switch S1 is actuated by a switching cam 46 disposed on the piston rod 4.
As shown in FIG. 5, the solenoid 52 of the valve 5 can be connected to the current-carrying line L by way of a contact means d1 and the solenoid 53 can be connected to the line L by way of contact means d2, d3 and d4 and the limit switch S1. The contact means d1 is actuated by the switch SE (FIG. 2). As will be described hereinafter, opening and closing of the contact means d2 and d3 is effected by an electrical control device 7 with preselection switches H1 to H4 and V1 to V4 (FIGS. 5 and 6) in dependence on the weight of material in the weighing device 16. A switching means S2 arranged on the carriage 1 acts on the contact means d4.
The mode of operation of the apparatus will now be described with reference to FIGS. 1 to 6. Firstly, the desired weight in respect of the amount of fiber which is to be removed from the individual fiber supply stations I to IV, in accordance with the predetermined proportions in the mixture, is set at the preselection switches H1, H2, H3 and H4. In addition, an initial or preliminary weight is set by means of the preselection switches V1, V2, V3 and V4, for each of the four fiber supply stations. Let it be assumed that the desired weight of the amount of fiber which is to be removed at the fiber supply station I is 10 kg and an initial weight of 2 kg is associated with the measurement value of the weighing device, being the value which corresponds to the respective weight of material in the weighing device. The preselection switches are controlled by a control arrangement 70 (see FIG. 6) which, in turn, receives control pulses from the weighing device.
The carriage 1 is in the region of the fiber supply station I in respect of which the desired weight of the amount of fiber to be removed has been set at the preselection switch H1. The control arrangement 70 which, after the preceding operation of emptying the receiving container 16, receives a corresponding control pulse, activates the preselection switch H1, whereby the set desired weight is supplied to a memory means 71 (see FIG. 6).
The gripper arm 2 is in the position shown in FIG. 1. The contact means d1 is opened as the chain 3 is tensioned and the metal base plate 38 of the housing 35 is thus outside its range of action on the switch SE. When the apparatus is switched on, the gripper arm 2 pivots to a position over the receiving container 16 which is formed as a weighing device. When this happens, a cam (not shown) which is arranged at the pivot axis of the gripper arm 2 actuates the switching means S2 (see FIG. 3) in the outwardly pivoted condition so that the contact means d4 (see FIG. 5) is closed. This, therefore, forms a current-conducting connection between the line L and the solenoid 53, by way of the closed contact means d4 and d3. The solenoid 53 is thus energized whereby compressed air flows through the conduits 54 and 51 into the cylinder 41 and urges the piston 40 with piston rod 4 downwardly. When this happens, the gripper fingers 21 pivot about the axis member 45 and open. The opening movement is terminated when the sensing stop 47 strikes against the limit stop 68. Although in this downward movement of the piston rod the swtiching arm 46 does in fact actuate the limit switch S1, nonetheless, this actuation has no effect on the solenoid 53 as the contact means d2 is open.
The gripper arm 2 now pivots over a bale B, the contact means d4 opening. The piston of the piston rod 33 (see FIG. 1) is then actuated with compressed air in such a way that the piston rod 33 moves upwardly and the gripper arm 2 with the gripper fingers 21 opened to a large width, moves down onto the bale B. When the gripper fingers 21 have penetrated into the bale to a predetermined depth and the chain 3 has become slackened in accordance with the above-mentioned predetermined depth, the base plate 38 of the housing 35 which is now moved on the rod 37 actuates the switch SE (see FIG. 2) whereby the contact means d1 is closed. This causes current to be supplied to the solenoid 52 of the valve 5 so that the solenoid 52 is energized and compressed air accordingly flows through the conduits 54 and 50 into the cylinder 41 and drives the piston 40 upwardly, while the compressed air in the upper part of the cylinder 41 escapes through the conduits 51 and 55. The upward movement of the piston rod 4 closes the gripper fingers 21.
The gripper arm 2 with the fiber material held by the gripper fingers 21 is lifted from the bale B by the piston rod 33 being moved downwardly by a flow of compressed air into the cylinder 34. The chain 3 tightens again so that the metal base plate 38 moves away from the switch SE and the contact means d1 is opened. The gripper arm 2 is then pivoted over the receiving container 16 of the weighing device; in that case, at the end of the pivotal movement, the switching means S2 is actuated and the contact means d4 is closed. This results in energization of the solenoid 53 and thus causes opening of the gripper fingers 21 in the above described manner so that the fiber material falls into the receiving container 16 which is in the form of the weighing device and which is moved downwardly by the weight of fiber material which is referred to hereinafter as the filling weight.
The resulting mechanical parameter is measured by means of a potentiometer or other suitable sensing means and supplied to an adding means 72 in the form of an electrical measurement value, for example, as an anlog signal which is proportional to the filling weight. In the weighing operation, the preselection switch VI at which the initial weight in respect of the fiber supply station I is set is activated by way of the control arrangement 70 so that the initial weight also passes into the adding means 72 and is there added to the measurement value of the filling weight in the receiving container. If the filling weight is supplied to the adding means 72 in the form of an analog signal, it will be appreciated that the digital value of the initial weight is also converted into an analog signal, in a digital-analog converter which is connected upstream of the adding means. The sum of the two weights is compared to the desired weight in a comparison stage 73. When the measurement value in respect of the filling weight, increased by the initial weight, reaches the above-mentioned desired weight, the comparison stage passes a control pulse to the control arrangement 70 which, on the one hand, then blocks the input to the adding means 72, being the input associated with the initial weight and, on the other hand, opens the contact means d3 and closes the contact means d2.
If, as indicated above for example, an initial weight of 2 kg is associated with a constituent of the mixture or its desired weight of 10 kg, then the control pulse is produced when the filling weight in the receiving container is 8 kg which corresponds to the desired weight less the initial weight.
As in the outwardly pivoted condition of the gripper arm 2 as described above the contact means d4 is closed, a current-conducting connection is made between the line L and the solenoid 53 by way of the contact means d4 and d2 and the closed contact of the limit switch S1. Energization of the solenoid 53 causes compressed air to flow through the conduits 54 and 51 into the cylinder 41 to urge the piston 40 downwardly so that the gripper fingers 21 open. However, the downward movement of the piston 40 is terminated at the moment that the switching cam 46 actuates the limit switch S1 and opens the contact thereof so that the gripper fingers 21 open to only a small width. The gripper arm is again lowered onto a bale B in the fiber supply station I in the above described manner, and now removes therefrom as a result of the small width of opening of the gripper fingers 21, only a small amount of fiber which is again dropped into the receiving container 16 forming the weighing device. As the initial weight is no longer passed to the adding means 72 in the subsequent weighing operation, the actual filling weight in the receiving container 16 is compared to the desired weight; and when the weight in the container reaches the desired weight, a switching pulse is applied to the control arrangement 70 which thereupon actuates the preselection switches H2 and V2 at which the desired weight and the initial weight in respect of the fiber supply station II are set. The carriage 1 now moves to station II and the above described operation of removing material is repeated at station II. In station II, as also in subsequent fiber supply stations III and IV, the fiber material removed is added to the material already in the receiving container 16 so that at the end all constituents of the mixture are in the receiving container 16 in the predetermined amount.
The above described mode of operation makes it possible to operate with the gripper fingers set to a wide degree of opening until the desired weight less the initial weight is reached, and then to operate with the gripper fingers at a small width of opening for the residual weight corresponding to the initial weight. This thus provides, on the one hand, for a high production capacity and, on the other hand, for a high degree of accuracy in producing the mixture.
In order further to increase the degree of accuracy in producing the mixture, as shown alternatively in FIG. 6, a full adding means 74 is connected to the input of the memory means 71. The desired weight and the filling weight are added in the full adding means 74 when the filling weight has reached the desired weight. The resulting total weight is inputted into the memory means 71. In this way, a new `zero point` is provided for each fiber supply station so that any variation in weight from the desired weight in regard to a constituent of the mixture is not transmitted to the respective next fiber supply station. If, for example, the assumed desired weight of 10 kg is exceeded by one kg in the fiber supply station I; and if the desired weight for the constituent of the mixture in fiber supply station II is 13 kg, the addition of these values now gives a desired weight of 24 kg which is applied to the memory means 71 and the comparison stage 73 connected to the output thereof. Therefore, as intended, 13 kg of fiber material is to be taken from the bale in the fiber supply station II until the above indicated desired weight is reached.
The degree of accuracy in producing the mixture can also be further increased by associating with the control device a computer unit which computes the relationship between the filling weight attained and the set desired weight and which increases the set desired weight of the subsequent fiber supply stations by the computed value.
The method which is described above, for example, with reference to a gripping means and in which an initial weight is associated with each constituent of the mixture and the amount of material taken from a bale is reduced when the filling weight reaches the desired weight of the constituent of the mixture, less the initial weight, may be the subject of modifications, like also the apparatus for carrying out the method. Thus, instead of increasing the filling weight by an initial weight or reducing the desired weight by said initial weight in respect of each constituent of the mixture, it is possible to establish an initial weight which is below the desired weight, and the amount of material taken from a bale is reduced when that weight is reached. This mode of operation follows the disclosed principle and is in accordance with the solution according to the invention.
In addition, the above described control device which establishes the desired weight of a constituent of the mixture, less an initial weight, or which also establishes an initial weight which is determined in respect of a constituent of the mixture and which is below the desired weight, which control device switches the gripping means over from a condition of wide opening of the fingers to a condition of small opening of the fingers when the filling weight reaches the desired weight less the initial weight or the initial weight when the matter is below the desired weight, can also be replaced by other means, for example, by microprocessors.
While a preferred embodiment of the invention has been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims. | A method an apparatus for opening and mixing the fibers from a plurality of bales according to a predetermined mixture. The device includes tongs-like gripper means which press into the fiber bales for removing fibers therefrom. A measuring means and a control means determine the width of opening of the gripper means. A control circuit is provided for receiving a signal representing the weight of the first pick-up from a particular bale and the weight of the fibers deposited in a receiver container. When the sum of these signals is equal to the preset desired weight of the fibers that are to be deposited in the receiver container, a compared signal is produced causing the tongs on successive pick-ups to be opened to a lesser degree. As a result, a high degree of accuracy is obtained when mixing to a predetermined ratio while maintaining a high production output. | 3 |
FIELD OF THE INVENTION
This invention relates to an epoxidation process comprising reacting an olefin, hydrogen and oxygen in the presence of a catalyst. The catalyst comprises a titanium or vanadium zeolite, palladium, and lead. Surprisingly, the process results in lower selectivity to undesired alkane byproduct formed by the hydrogenation of olefin compared to similar catalyst systems that do not contain lead.
BACKGROUND OF THE INVENTION
Many different methods for the preparation of epoxides have been developed. Generally, epoxides are formed by the reaction of an olefin with an oxidizing agent in the presence of a catalyst. The production of propylene oxide from propylene and an organic hydroperoxide oxidizing agent, such as ethylbenzene hydroperoxide or tert-butyl hydroperoxide, is commercially practiced technology. This process is performed in the presence of a solubilized molybdenum catalyst, see U.S. Pat. No. 3,351,635, or a heterogeneous titania on silica catalyst, see U.S. Pat. No. 4,367,342. Another commercially practiced technology is the direct epoxidation of ethylene to ethylene oxide by reaction with oxygen over a silver catalyst. Unfortunately, the silver catalyst has not proved useful in commercial epoxidation of higher olefins.
Besides oxygen and alkyl hydroperoxides, another oxidizing agent useful for the preparation of epoxides is hydrogen peroxide. U.S. Pat. Nos. 4,833,260, 4,859,785, and 4,937,216, for example, disclose the epoxidation of olefins with hydrogen peroxide in the presence of a titanium silicate catalyst.
Much current research is conducted in the direct epoxidation of olefins with oxygen and hydrogen. In this process, it is believed that oxygen and hydrogen react in situ to form an oxidizing agent. Many different catalysts have been proposed for use in the direct epoxidation of higher olefins. Typically, the catalyst comprises a noble metal that is supported on a titanosilicate. For example, JP 4-352771 discloses the formation of propylene oxide from propylene, oxygen, and hydrogen using a catalyst containing a Group VIII metal such as palladium on a crystalline titanosilicate. The Group VIII metal is believed to promote the reaction of oxygen and hydrogen to form a hydrogen peroxide in situ oxidizing agent. U.S. Pat. No. 5,859,265 discloses a catalyst in which a platinum metal, selected from Ru, Rh, Pd, Os, Ir and Pt, is supported on a titanium or vanadium silicalite. Other direct epoxidation catalyst examples include gold supported on titanosilicates, see for example PCT Intl. Appl. WO 98/00413.
One disadvantage of the described direct epoxidation catalysts is that they are prone to produce non-selective by-products such as glycols or glycol ethers formed by the ring-opening of the epoxide product or alkane by-product formed by the hydrogenation of olefin. U.S. Pat. No. 6,008,388 describes a direct olefin epoxidation process in which the selectivity for the reaction of olefin, oxygen, and hydrogen in the presence of a noble metal-modified titanium zeolite is enhanced by the addition of a nitrogen compound such as ammonium hydroxide to the reaction mixture. U.S. Pat. No. 6,399,794 teaches the use of ammonium bicarbonate modifiers to decrease the production of ring-opened by by-products. U.S. Pat. No. 6,005,123 teaches the use of phosphorus, sulfur, selenium or arsenic modifiers such as triphenylphosphine or benzothiophene to decrease the production of propane.
As with any chemical process, it is desirable to attain still further improvements in the epoxidation methods and catalysts. We have discovered an effective, convenient process to form an epoxidation catalyst and its use in the epoxidation of olefins.
SUMMARY OF THE INVENTION
The invention is an olefin epoxidation process that comprises reacting olefin, oxygen, and hydrogen in the presence of a catalyst comprising a titanium or vanadium zeolite, palladium, and lead. This process surprisingly gives significantly reduced alkane by-product formed by the hydrogenation of olefin.
DETAILED DESCRIPTION OF THE INVENTION
The process of the invention employs a catalyst that comprises a titanium or vanadium zeolite, palladium, and lead. Titanium or vanadium zeolites comprise the class of zeolitic substances wherein titanium or vanadium atoms are substituted for a portion of the silicon atoms in the lattice framework of a molecular sieve. Such substances, and their production, are well known in the art. See for example, U.S. Pat. Nos. 4,410,501 and 4,666,692.
Suitable titanium or vanadium zeolites are those crystalline materials having a porous molecular sieve structure with titanium or vanadium atoms substituted in the framework. The choice of titanium or vanadium zeolite employed will depend upon a number of factors, including the size and shape of the olefin to be epoxidized. For example, it is preferred to use a relatively small pore titanium or vanadium zeolite such as a titanium silicalite if the olefin is a lower aliphatic olefin such as ethylene, propylene, or 1-butene. Where the olefin is propylene, the use of a TS-1 titanium silicalite is especially advantageous. For a bulky olefin such as cyclohexene, a larger pore titanium or vanadium zeolite such as a zeolite having a structure isomorphous with zeolite beta may be preferred.
Particularly preferred titanium or vanadium zeolites include the class of molecular sieves commonly referred to as titanium silicalites, particularly “TS-1” (having an MFI topology analogous to that of the ZSM-5 aluminosilicate zeolites), “TS-2” (having an MEL topology analogous to that of the ZSM-11 aluminosilicate zeolites), and “TS-3” (as described in Belgian Pat. No. 1,001,038). Titanium-containing molecular sieves having framework structures isomorphous to zeolite beta, mordenite, ZSM-48, ZSM-12, and MCM-41 are also suitable for use. The titanium zeolites preferably contain no elements other than titanium, silicon, and oxygen in the lattice framework, although minor amounts of boron, iron, aluminum, sodium, potassium, copper and the like may be present.
Preferred titanium zeolites will generally have a composition corresponding to the following empirical formula xTiO 2 (1−x)SiO 2 where x is between 0.0001 and 0.5000. More preferably, the value of x is from 0.01 to 0.125. The molar ratio of Si:Ti in the lattice framework of the zeolite is advantageously from 9.5:1 to 99:1 (most preferably from 9.5:1 to 60:1). The use of relatively titanium-rich zeolites may also be desirable.
The catalyst employed in the process of the invention optionally comprises a carrier. The carrier is preferably a porous material. Carriers are well-known in the art. For instance, the carrier can be inorganic oxides, clays, carbon, and organic polymer resins. Preferred inorganic oxides include oxides of Group 2, 3, 4, 5, 6, 13, or 14 elements. Particularly preferred inorganic oxide carriers include silica, alumina, silica-aluminas, titania, zirconia, niobium oxides, tantalum oxides, molybdenum oxides, tungsten oxides, amorphous titania-silica, amorphous zirconia-silica, amorphous niobia-silica, and the like. The carrier may be a zeolite, but is not a titanium or vanadium zeolite. Preferred organic polymer resins include polystyrene, styrene-divinylbenzene copolymers, crosslinked polyethyleneimines, and polybenzimidizole. Suitable carriers also include organic polymer resins grafted onto inorganic oxide carriers, such as polyethylenimine-silica. Preferred carriers also include carbon. Particularly preferred carriers include carbon, silica, silica-aluminas, titania, zirconia, and niobia.
Preferably, the carrier has a surface area in the range of about 1 to about 700 m 2 /g, most preferably from about 10 to about 500 m 2 /g. Preferably, the pore volume of the carrier is in the range of about 0.1 to about 4.0 mL/g, more preferably from about 0.5 to about 3.5 mL/g, and most preferably from about 0.8 to about 3.0 mL/g. Preferably, the average particle size of the carrier is in the range of about 0.1 to about 500 μm, more preferably from about 1 to about 200 μm, and most preferably from about 10 to about 100 μm. The average pore diameter is typically in the range of about 10 to about 1000 Å, preferably about 20 to about 500 Å, and most preferably about 50 to about 350 Å.
The catalyst employed in the process of the invention also comprises palladium and lead. The palladium and lead may be added to the catalyst in a variety of ways: (1) the palladium and lead may both be supported on the titanium or vanadium zeolite; (2) palladium and lead may both be supported on an a carrier, and then mixed with titanium or vanadium zeolite to form the catalyst; (3) palladium may be incorporated into the titanium or vanadium zeolite, lead supported on the carrier, and then mixed to form the catalyst; (4) lead may be incorporated into the titanium or vanadium zeolite, palladium supported on the carrier, and then mixed to form the catalyst; or (5) palladium may be incorporated into the titanium or vanadium zeolite, and then mixed with an insoluble lead salt to form the catalyst.
The typical amount of palladium present in the catalyst will be in the range of from about 0.01 to 20 weight percent, preferably 0.01 to 5 weight percent. The manner in which the palladium is incorporated into the catalyst is not considered to be particularly critical. For example, the palladium may be supported on the titanium or vanadium zeolite or the carrier by impregnation or titanium or vanadium zeolite or the carrier by ion-exchange with, for example, palladium tetraammine chloride.
There are no particular restrictions regarding the choice of palladium compound used as the source of palladium. For example, suitable compounds include the nitrates, sulfates, halides (e.g., chlorides, bromides), carboxylates (e.g. acetate), and amine complexes of palladium. Similarly, the oxidation state of the palladium is not considered critical. The palladium may be in an oxidation state anywhere from 0 to +4 or any combination of such oxidation states. To achieve the desired oxidation state or combination of oxidation states, the palladium compound may be fully or partially pre-reduced after addition to the catalyst. Satisfactory catalytic performance can, however, be attained without any pre-reduction. To achieve the active state of palladium, the catalyst may undergo pretreatment such as thermal treatment in nitrogen, vacuum, hydrogen, or air.
The catalyst used in the process of the invention also contains lead. The typical amount of lead present in the catalyst will be in the range of from about 0.001 to 10 weight percent, preferably 0.001 to 2 weight percent. Preferably, the weight ratio of palladium to lead in the catalyst is in the range of 1 to 100. While the choice of lead compound used as the lead source in the catalyst is not critical, suitable compounds include lead carboxylates (e.g., acetate), halides (e.g., chlorides, bromides, iodides), nitrates, cyanides, and sulfides. The lead may be added to the titanium or vanadium zeolite before, during, or after palladium addition, it is preferred to add the lead promoter at the same time that palladium is introduced. Any suitable method can be used for the incorporation of lead into the catalyst. As with palladium addition, the lead may be supported on the titanium or vanadium zeolite or the carrier by impregnation. Incipient wetness techniques may also be used to incorporate the lead.
The catalyst may additionally comprise other noble metals, including gold, platinum, silver, and rhodium. Gold is especially preferred. The typical amount of additional noble metal in the catalyst will be in the range of from about 0.01 to 10 weight percent, preferably 0.01 to 2 weight percent. While the choice of noble metal compound used as the noble metal source in the catalyst is not critical, suitable compounds include noble metal halides (e.g., chlorides, bromides, iodides), oxides, cyanides, and sulfides, as well as more complex species such as tetrachloroauric acid optionally treated with base. The noble metal may be added to the titanium or vanadium zeolite or to the carrier before, during, or after palladium addition. Any suitable method can be used for the incorporation of gold into the catalyst. As with palladium addition, the gold may be supported on the zeolite by impregnation, incipient wetness techniques, or by a deposition-precipitation method (as described in U.S. Pat. No. 5,623,090 for gold compounds).
After palladium, optional noble metal, and lead incorporation, the catalyst is isolated. Suitable catalyst isolation methods include filtration and washing, rotary evaporation and the like. The catalyst is typically dried at a temperature greater than about 50° C. prior to use in epoxidation. The drying temperature is preferably from about 50° C. to about 200° C. The catalyst may additionally comprise a binder or the like and may be molded, spray dried, shaped or extruded into any desired form prior to use in epoxidation.
After catalyst formation, the catalyst may be optionally thermally treated in a gas such as nitrogen, helium, vacuum, hydrogen, oxygen, air, or the like. The thermal treatment temperature is typically from about 20 to about 800° C. It is preferred to thermally treat the catalyst in the presence of an oxygen-containing gas at a temperature from about 200 to 650° C., and optionally reduce the support catalyst in the presence of a hydrogen-containing gas at a temperature from about 20 to 600° C.
The epoxidation process of the invention comprises contacting an olefin, oxygen, and hydrogen in the presence of the catalyst. Suitable olefins include any olefin having at least one carbon-carbon double bond, and generally from 2 to 60 carbon atoms. Preferably the olefin is an acyclic alkene of from 2 to 30 carbon atoms; the process of the invention is particularly suitable for epoxidizing C 2 -C 6 olefins. More than one double bond may be present, as in a diene or triene for example. The olefin may be a hydrocarbon (i.e., contain only carbon and hydrogen atoms) or may contain functional groups such as halide, carboxyl, hydroxyl, ether, carbonyl, cyano, or nitro groups, or the like. The process of the invention is especially useful for converting propylene to propylene oxide.
Oxygen and hydrogen are also required for the epoxidation process. Although any sources of oxygen and hydrogen are suitable, molecular oxygen and molecular hydrogen are preferred.
Epoxidation according to the invention is carried out at a temperature effective to achieve the desired olefin epoxidation, preferably at temperatures in the range of 0-250° C., more preferably, 20-100° C. The molar ratio of hydrogen to oxygen can usually be varied in the range of H 2 :O 2 =1:10 to 5:1 and is especially favorable at 1:5 to 2:1. The molar ratio of oxygen to olefin is usually 2:1 to 1:20, and preferably 1:1 to 1:10. A carrier gas may also be used in the epoxidation process. As the carrier gas, any desired inert gas can be used. The molar ratio of olefin to carrier gas is then usually in the range of 100:1 to 1:10 and especially 20:1 to 1:10.
As the inert gas carrier, noble gases such as helium, neon, and argon are suitable in addition to nitrogen and carbon dioxide. Saturated hydrocarbons with 1-8, especially 1-6, and preferably with 1-4 carbon atoms, e.g., methane, ethane, propane, and n-butane, are also suitable. Nitrogen and saturated C 1 -C 4 hydrocarbons are the preferred inert carrier gases. Mixtures of the listed inert carrier gases can also be used.
Specifically in the epoxidation of propylene, propane or methane can be supplied in such a way that, in the presence of an appropriate excess of carrier gas, the explosive limits of mixtures of propylene, propane (methane), hydrogen, and oxygen are safely avoided and thus no explosive mixture can form in the reactor or in the feed and discharge lines.
The amount of catalyst used may be determined on the basis of the molar ratio of the titanium contained in the titanium zeolite to the olefin that is supplied per unit time. Typically, sufficient catalyst is present to provide a titanium/olefin per hour molar feed ratio of from 0.0001 to 0.1.
Depending on the olefin to be reacted, the epoxidation according to the invention can be carried out in the liquid phase, the gas phase, or in the supercritical phase. When a liquid reaction medium is used, the catalyst is preferably in the form of a suspension or fixed-bed. The process may be performed using a continuous flow, semi-batch or batch mode of operation.
If epoxidation is carried out in the liquid (or supercritical or subcritical) phase, it is advantageous to work at a pressure of 1-100 bars and in the presence of one or more solvents. Suitable solvents include any chemical that is a liquid under reaction conditions, including, but not limited to, oxygenated hydrocarbons such as alcohols, ethers, esters, and ketones, aromatic and aliphatic hydrocarbons such as toluene and hexane, liquid CO 2 (in the supercritical or subcritical state), and water. Preferable solvents include water, liquid CO 2 , and oxygenated hydrocarbons such as alcohols, ethers, esters, ketones, and the like, or mixtures thereof. Preferred oxygenated solvents include lower aliphatic C 1 -C 4 alcohols such as methanol, ethanol, isopropanol, and tert-butanol, or mixtures thereof, and water. Fluorinated alcohols can be used. It is particularly preferable to use mixtures of the cited alcohols with water.
If epoxidation is carried out in the liquid (or supercritical or subcritical) phase, it is advantageous to use a buffer. The buffer will typically be added to the solvent to form a buffer solution. The buffer solution is employed in the reaction to inhibit the formation of glycols or glycol ethers during epoxidation. Buffers are well known in the art.
Buffers useful in this invention include any suitable salts of oxyacids, the nature and proportions of which in the mixture, are such that the pH of their solutions may range from 3 to 10, preferably from 4 to 9 and more preferably from 5 to 7. Suitable salts of oxyacids contain an anion and cation. The anion portion of the salt may include anions such as phosphate, monohydrogenphosphate, dihydrogenphosphate, sulfate, carbonate, bicarbonate, carboxylates (e.g., acetate, phthalate, and the like), citrate, borate, hydroxide, silicate, aluminosilicate, or the like. The cation portion of the salt may include cations such as ammonium, alkylammoniums (e.g., tetraalkylammoniums, pyridiniums, and the like), alkali metals, alkaline earth metals, or the like. Examples include NH 4 , NBu 4 , NMe 4 , Li, Na, K, Cs, Mg, and Ca cations. More preferred buffers include alkali metal phosphate and ammonium phosphate buffers. Buffers may preferably contain a combination of more than one suitable salt. Typically, the concentration of buffer in the solvent is from about 0.0001 M to about 1 M, preferably from about 0.001 M to about 0.3 M. The buffer useful in this invention may also include the addition of ammonia gas to the reaction system.
The following examples merely illustrate the invention. Those skilled in the art will recognize many variations that are within the spirit of the invention and scope of the claims.
COMPARATIVE EXAMPLE 1
Preparation of Pd/TS-1 Catalyst
Spray dried TS1 (15.778 pounds; 20 wt. % silica binder, 2.1 wt. % Ti, calcined at 550° C.) is added to deionized water (17.89 L) in a 50 liter mixing tank and stirred by an agitator at 500 rpm. The pH of the slurry is adjusted up to 7.0 using 3% aqueous ammonium hydroxide, then tetraammine palladium nitrate aqueous solution (0.166 pounds Pd, diluted to 1 liter) is added over a one-minute period through a subsurface injection, with agitation. The pH of the slurry is maintained at 7.0 during the palladium addition by adding the 3% ammonium hydroxide solution. After palladium addition, the pH is adjusted up to 7.5 with ammonium hydroxide and the slurry is agitated at 30° C. for 60 minutes while maintaining the pH at 7.4. The slurry is filtered and washed (three times with 17 L of deionized water). The solids are then dried in vacuum at 50° C. until a constant weight is obtained, calcined at 300° C. in air for 1 hour, and then treated with 4% H 2 in nitrogen for 1 hour to form Comparative Catalyst 1. Comparative Catalyst 1 contains 0.1 wt. % palladium, 2.1 wt. % titanium and 44 wt. % silicon.
EXAMPLE 2
Preparation OF Pd—Pb/TS-1 Catalyst
Catalyst 1 (8.4 g) and deionized water (25 mL) are placed in a 3-neck 100 mL flask. A lead acetate solution (0.08 g of Pb(OAc) 2 in 10 mL of deionized water) is then added to the slurry with stirring, and the reaction mixture was heated at 75-82° C. (using a hot oil bath) and stirred for 45 minutes. The solids are filtered, rinsed four times with deionized water (20 mL each), and dried in a vacuum oven at 65° C. for 2 hours to form Catalyst 2. Catalyst 2 contains 0.08 wt. % palladium, 0.35 wt. % lead, and 2.0 wt. % titanium.
EXAMPLE 3
Insoluble Lead Salts
Catalyst 3A is PbTiO 3 , a product of Alfa Aesar.
Catalyst 3B is PbSO 4 , a product of Sigma-Aldrich.
Catalyst 3C is PbZrO 3 , a product of Sigma-Aldrich.
Catalyst 3D is PbNiO 3 , a product of Sigma-Aldrich.
EXAMPLE 4
Pd—Pb Supported Catalysts
Catalyst 4A is Pd—Pb/CaCO 3 , a product of Sigma-Aldrich.
Catalyst 4B is Pd—Pb/BaSO 4 , a product of Alfa Aesar.
EXAMPLE 5
Preparation of Pd—Au—Pb/TiO 2 Catalyst
Pd—Au/TiO 2 (4.67 g, made according to the procedure of Example 8A) and deionized water (30 mL) are placed in a 3-neck 100 mL flask. A lead acetate solution (0.030 g of Pb(OAc) 2 in 15 mL of deionized water) is then added to the slurry with stirring, and the reaction mixture was heated at 75-85° C. (using a hot oil bath) and stirred for 45 minutes. The solids are filtered, rinsed four times with deionized water (20 mL each), and dried in a vacuum oven at 65° C. for 2.4 hours to form Catalyst 5. Catalyst 5 contains 0.97 wt. % palladium, 0.50 wt. % gold, 0.38 wt. % lead, and 58 wt. % titanium.
EXAMPLE 6
Epoxidation Reaction Using Catalysts from Examples 1-5
To evaluate the performance of the Comparative Catalyst 1 and Catalysts 2, 3A, 3B, 3C, 3D, 4A, 4B, and 5, the epoxidation of propylene using oxygen and hydrogen is carried out. The following procedure is employed:
A reactor system, consisting of a 600-mL pressure reactor and a 1.5 L saturator, is charged with a mixture of methanol (90 g) and 0.1 M ammonium dihydrogenphosphate (30 g) neutralized to pH 6 with dilute ammonium hydroxide. The catalyst or admixtures of catalysts (4.0 g total) are then added to the reactor, and the slurry is heated to 60° C. at 300 psi (2068 kPa). Run 6A uses Catalyst 1 (4 g). Run 6B uses Catalyst 2 (4 g). Run 6C uses a mixture of Catalyst 3A (0.1 g) and Catalyst 1 (3.9 g). Run 6D uses a mixture of Catalyst 3B (0.1 g) and Catalyst 1 (3.9 g). Run 6E uses a mixture of Catalyst 3C (0.1 g) and Catalyst 1 (3.9 g). Run 6F uses a mixture of Catalyst 3D (0.1 g) and Catalyst 1 (3.9 g). Run 6G uses a mixture of Catalyst 4A (0.05 g) and TS-1 (3.95 g). Run 6H uses a mixture of Catalyst 4B (0.2 g) and TS-1 (3.8 g). Run 61 uses a mixture of Catalyst 5 (0.1 g) and TS-1 (3.9 g).
A gaseous feed consisting of 46 cc/min hydrogen, 277 cc/min propylene, and 4318 cc/min of 5% oxygen in nitrogen is introduced into the pressure reactor via a fine frit. The exit gas is analyzed by on-line GC, while PO and ring-opened products in the liquid phase are analyzed at the termination of the reaction. The reaction is carried out for 18 hours, but can be run longer. The results of the GC analyses are used to calculate the productivity and selectivities shown in the Table 1.
COMPARATIVE EXAMPLE 7
Preparation of Pd—Au/TiO 2 catalysts
Comparative Catalyst 7A: Aqueous sodium tetrachloro aurate (0.265 g, 20.74 wt. % gold) and solid disodium tetrachloro palladate (0.275 g) are added to deionized water (25 g) with stirring. After the palladium and gold compounds dissolve, anatase TiO 2 (10 g, 1 micron average size, 30 m 2 /g) and sodium bicarbonate (0.25 g) are added to the palladium/gold solution. The slurry is then reacted for 24 h at 23° C., filtered, and the solids are washed with deionized water two times, followed by calcination in air at 220° C. The calcined solids are then washed with deionized water until the final filtrate contains 1 ppm chloride, then dried and calcined in air in a muffle furnace by heating at 10° C./min to 110° C. for 2 h and then heating at 2° C./min to 300° C. for 4 h. The calcined solids are then transferred to a quartz tube and treated with a 4 vol. % hydrogen/nitrogen stream (100 cc/hr) at 100° C. for 3h. Comparative Catalyst 7A contains 0.9 wt. % palladium, 0.55 wt. % gold and 59 wt. % titanium.
Comparative Catalyst 7B: Aqueous sodium tetrachloro aurate (0.265 g, 20.74 wt. % gold) and solid disodium tetrachloro palladate (0.275 g) are added to deionized water (25 g) with stirring. After the palladium and gold compounds dissolve, spray dried anatase TiO 2 (10 g, 35 micron average size, 40 m 2 /g, calcined at 700° C.) and sodium bicarbonate (0.26 g) are added to the palladium/gold solution. The slurry is then reacted for 4 h at 40° C., filtered, and the solids are washed with deionized water (30 g), followed by calcination in air in a muffle furnace by heating at 10° C./min to 110° C. for 6 h and then at 2° C./min to 300° C. for 4 h. The calcined solids are then washed with deionized water (30 g, 6 times), then dried in a vacuum oven at 50° C., and transferred to a quartz tube and treated with a 4 vol. % hydrogen/nitrogen stream (100 cc/hr) at 100° C. for 1 h, and then purged with nitrogen for 1 h. Comparative Catalyst 7B contains 0.95 wt. % palladium, 0.6 wt. % gold and 58 wt. % titanium.
EXAMPLE 8
Preparation of Pd—Au—Pb/TiO 2 catalyst
Catalyst 8A: Aqueous sodium tetrachloro aurate (0.265 g, 20.74 wt. % gold) and solid disodium tetrachloro palladate (0.275 g) are added to deionized water (25 g) with stirring. After the palladium and gold compounds dissolve, anatase TiO 2 (10 g, 1 micron average size, 87 m 2 /g) and sodium bicarbonate (0.65 g) are added to the palladium/gold solution to give a pH of 6.3. The pH is adjusted to 7 by the addition of two portions of solid sodium bicarbonate (0.25 g each). The slurry is then reacted for 4 h at 40° C., filtered, and the solids are washed with deionized water (30 g), followed by calcination in air in a muffle furnace by heating at 10° C./min to 110° C. for 6 h and then at 2° C./min to 300° C. for 4 h. The calcined solids are then washed with deionized water (30 g, six times), then dried in a vacuum oven at 50° C., and transferred to a quartz tube and treated with a 4 vol. % hydrogen/nitrogen stream (100 cc/hr) at 100° C. for 1 h, and then purged with nitrogen for 1 h.
The Pd—Au/TiO 2 solids (4.67 g) are then slurried in deionized water (30 g), and a solution of lead acetate (0.03 gram) was dissolved in 15 grams of deionized water is added to the slurry. The resulting slurry is stirred at 75 to 85° C. for 45 min, filtered, washed with deionized water (20 g, four times), and dried in a vacuum oven at 65° C. for 2.4 h. Catalyst 8A contains 0.95 wt. % palladium, 0.5 wt. % gold, and 0.4 wt % lead.
Catalyst 8B: Aqueous sodium tetrachloro aurate (0.795 g, 20.74 wt. % gold) and solid disodium tetrachloro palladate (0.825 g) are added to deionized water (120 g) with stirring. After the palladium and gold compounds dissolve, spray dried anatase TiO 2 (30 g, 35 micron average size, 43 m 2 /g, calcined at 700° C.) is added to the palladium/gold solution, followed by the addition of lead acetate (0.22 g). The pH is adjusted to 7.02 by the addition of solid sodium bicarbonate (4.75 g required). The slurry is then reacted for 4 h at 40° C., filtered, and the solids are washed with deionized water (100 g, two times), followed by calcination in air in a muffle furnace by heating at 10° C./min to 110° C. for 6 h and then at 2° C./min to 300° C. for 4 h. The calcined solids are then washed with deionized water (100 g, six times), then dried in a vacuum oven at 50° C. overnight, and transferred to a quartz tube and treated with a 4 vol. % hydrogen/nitrogen stream (100 cc/hr) at 100° C. for 1 h. Catalyst 8B contains 0.95 wt. % palladium, 0.45 wt. % gold, and 0.32 wt % lead.
EXAMPLE 9
Epoxidation Reaction Using Catalysts from Examples 7-8
To evaluate the performance of Comparative Catalysts 7A and 7B and Catalysts 8A and 8B, the epoxidation of propylene using oxygen and hydrogen was carried out. The following procedure is employed:
A 300 cc stainless steel reactor is charged with catalyst (0.07 g) and TS1 powder (0.63 g; 2 wt. % Ti), a buffer (13 g, 0.1 M aqueous ammonium phosphate, pH=6), and methanol (100 g). The reactor is then charged to 300 psig (2068 kPa) of a feed consisting of 2% hydrogen, 4% oxygen, 5% propylene, 0.5% methane and the balance nitrogen (volume %). The pressure in the reactor is maintained at 300 psig (2068 kPa) via a back pressure regulator with the feed gases passed continuously through the reactor at 1600 cc/min (measured at 23° C. and one atmosphere pressure). In order to maintain a constant solvent level in the reactor during the run, the oxygen, nitrogen and propylene feeds are passed through a two-liter stainless steel vessel (saturator), containing 1.5 liters of methanol, preceding the reactor. The reactor is stirred at 1500 rpm. The reaction mixture is heated to 60° C. and the gaseous effluent is analyzed by an online GC every hour and the liquid analyzed by offline GC at the end of the 18 hour run. Propylene oxide and equivalents (“POE”), which include propylene oxide (“PO”), propylene glycol (“PG”), and propylene glycol methyl ethers (PMs), are produced during the reaction, in addition to propane formed by the hydrogenation of propylene. The results of the GC analyses are used to calculate the productivity and selectivities shown in the Table 2.
TABLE 1
Epoxidation Results from Example 6
PO/POE
Propylene
Admixture
Selectivity
Selectivity
Run #
Catalyst
Component
(%) 1
(%) 2
Productivity 3
6A*
1
—
84.6
79.1
0.535
6B
2
—
84.3
88.5
0.376
6C
3A
Pd/TS-1
93.7
82.8
0.549
6D
3B
Pd/TS-1
87.8
83.3
0.511
6E
3C
Pd/TS-1
85.3
81.6
0.464
6F
3D
Pd/TS-1
85.9
82.2
0.529
6G
4A
TS-1
91.2
86.8
0.416
6H
4B
TS-1
78.9
92.7
0.517
6I
5
TS-1
89.1
89.2
0.453
1 PO/POE Selectivity = moles PO/(moles PO + moles propylene glycols) * 100.
2 Propylene Selectivity = 100 − (moles propane/moles POE + moles propane) * 100.
3 Productivity = grams POE produced/gram of catalyst per hour.
*Comparative Example
TABLE 2
Epoxidation Results from Example 9
PO/POE
Propylene
Selectivity
Selectivity
Catalyst
(%) 1
(%) 2
Productivity 3
7A*
85
47
0.91
8A
82
70
0.93
7B*
88
54
0.57
8B
89
74
0.62
1 PO/POE Selectivity = moles PO/(moles PO + moles propylene glycols) * 100.
2 Propylene Selectivity = 100 − (moles propane/moles POE + moles propane) * 100.
3 Productivity = grams POE produced/gram of catalyst per hour.
*Comparative Example | A process for producing an epoxide comprising reacting an olefin, hydrogen and oxygen in the presence of a catalyst comprising a titanium or vanadium zeolite, palladium, and lead. The process results in significantly reduced alkane by-product formed by the hydrogenation of olefin. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates to windows, and more particularly, relates to window operators such as may be used in a casement windows or alternatively, in awning windows.
BACKGROUND OF THE INVENTION
[0002] Casement windows are well known in the art and are widely used in new constructions. A casement window is hinged at the side and has a window sash which is movably mounted within a frame by a pair of hinges mounted between the window frame at the top and bottom of the window sash. The arrangement is normally one in which a track is mounted to the window frame to interconnect a track and window sash. In this respect, a support arm is pivotably connected to the sash arm and to the track. The sash arm is also pivotably connected to a mounting shoe which is supported and guided for movement lengthwise of the track which is mounted on the window.
[0003] An alternative arrangement is to provide an intervening length between the sash arm and the movable shoe to provide for an offset sash arm. Such an arrangement typically includes a second intervening length between the support arm and the movable shoe to provide further support.
[0004] An awning window, on the other hand, is pivoted at the top by hinges. Such an arrangement is desirable in certain situations since the window pivots outwardly from the bottom and will remain in a position to shelter or shield the opening.
[0005] Casement window operators are also well known in the art. The window operator typically will utilize a hand crank which is rotatable and which in turn drives a worm gear. The worm gear in turn will drive gearing which is connected to the arm which pushes the window sash open. As aforementioned, the worm gear assembly includes a gear shaft having the worm at one end with the other end extending outwardly through the housing to engage the crank.
[0006] As described above, there are different opening arrangements for casement windows. A first arrangement utilizes a single arm operator which has an arm which pivots about an axis that is fixed with respect to the window frame and worm gear. A remote end of the arm carries a bearing which slides in a track mounted on the underside of the sash. The known disadvantage of single arm operators is the torque required to move the sash towards its fully open position. Thus, the force required both causes difficulty for the person opening the window and also leads to excessive wear of the mechanism.
[0007] A second known type of casement window operator is typically known as a “split arm”. A split arm operator includes a second arm which has a pivot point in the middle of the second arm and the remote end of the second arm is secured through a pivotable mounting to a fixed point on the sash. This arrangement allows the window to extend to its fully open position. However, it does suffer from the disadvantage of requiring excessive force at the time of the initial opening of the sash.
[0008] A third type of window operator is typically known as a “dual arm”. The dual arm operator has one arm which rotates about a fixed axis and a housing which carries at its far end a bearing to slide in a track mounted to the window sash. There is also a second arm which has a pivot joint and which is secured at its remote end by a pivotable but fixed connection to the sash.
SUMMARY OF THE INVENTION
[0009] It is an object of the present invention to provide improvements to casement window operators wherein on site adjustments may easily be made.
[0010] It is a further object of the present invention to provide window operators which include a locking mechanism.
[0011] It is a further object of the present invention to provide a locking mechanism which ensures that the window operator is not utilized until the window is unlocked.
[0012] It is a further object of the present invention to provide a window operator for an awning window which allows identical movement on both sides of the window.
[0013] According to a further aspect of the present invention, there is provided an operator for a window comprising a base designed to be secured to a window sash, an arm having first and second ends, the first end being secured to the base, the first end of the arm having a worm wheel formed thereon, a shaft having a worm operatively connected to the worm wheel, a handle secured to the shaft, a locking mechanism comprising a multi-point tie bar, and an actuator connected to a rack and pinion gear arrangement to move the multi-point tie bar between open and locked positions.
[0014] According to a still further aspect of the present invention, there is provided an operator for a window comprising a base designed to be secured to a window sash, an arm having first and second ends, the first end being secured to the base, the first end of the arm having a worm wheel formed thereon, a shaft having a worm operatively connected to the worm wheel, a handle secured to the shaft, a locking mechanism comprising a blade, a guide mounted on the sash, the blade being movable within the guide, and an actuator connected to the blade to move the blade between open and locked positions, the actuator, when in the locked position, preventing access to the handle, the actuator when moved to the open position allowing access to the handle.
[0015] In one of the above aspects, the operator is used with casement windows wherein the window is hinged on the side between the top and bottom of the window sash. The operator of the present invention may be utilized with a single arm, split arm or dual arm arrangement.
[0016] As mentioned above, the operator preferably utilizes a worm wheel or gear formed at a first end of an arm and which worm wheel is designed to engage a worm formed at one end of a shaft. The arm may be secured to the base by suitable securement members.
[0017] In one embodiment of the present invention, there is provided a multi point tie bar which is utilized in a locking mechanism. A locking mechanism is incorporated with the operator within the same housing. The locking mechanism is arranged such that the window must be unlocked prior to use of the window crank for opening of the window. This arrangement overcomes the problem of a user attempting to open the window while still locked. Frequently, excessive force is utilized by the person attempting to open the window which can lead to breakage of one or more of the components.
[0018] The locking mechanism should meet several standards for the industry. One requirement for many manufacturers is that integrated locking and opening mechanisms fit within pre-designed openings in the window. To do so, a compact design must be utilized. In the instant invention, the use of a rack and pinion gear allows for a compact design which also provides an arrangement which resists opening from the exterior of the window.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Having thus generally described the invention, reference will be now made to the accompanying drawings illustrating embodiments thereof, in which:
[0020] FIG. 1 is a perspective view of a window assembly using an operator;
[0021] FIG. 2A is a perspective view of the window operator;
[0022] FIG. 2B is an exploded view thereof;
[0023] FIGS. 3A and B are perspective views of a portion of an operator utilizing a double arm arrangement;
[0024] FIG. 4 is a top plan view of the operator of FIGS. 3A and 3B ;
[0025] FIG. 5 is a top plan view of the operator of FIGS. 2A and 2B ;
[0026] FIG. 6 is an exploded view of a portion of the window operator illustrating a locking system;
[0027] FIG. 7 is an exploded view of a portion of the locking system of FIG. 5 ;
[0028] FIG. 8 is a partial plan view illustrating a portion of the locking system;
[0029] FIG. 9 is a perspective view thereof;
[0030] FIG. 10 is a plan view, partially in cutaway, of a reverser used in an awning window;
[0031] FIG. 11 is a sectional view thereof;
[0032] FIGS. 12A , B and C illustrate operation of the actuator and handle;
[0033] FIGS. 13A , B, C and D are top views thereof; and
[0034] FIG. 14 is a plan view of a further embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0035] Referring to the drawings in greater detail and by reference characters thereto, there is illustrated in FIG. 1 a window generally designated by reference numeral 10 and which window 10 includes a window frame 12 and a sash 14 . An operator 16 is utilized to open and close a window which is of the casement type.
[0036] Operator 16 , as may be better seen in FIGS. 2 a and 2 b , includes a base 18 which has a plurality of mounting apertures 20 . As is conventional, base 18 may be secured to the window frame by screws or other suitable mechanical fasteners.
[0037] Mounted on the upper side of base 18 are posts 22 and 24 for reasons which will become apparent hereinbelow. Base 18 also has a aperture 26 .
[0038] In the illustrated embodiment, operator 16 includes a first arm 28 and a second arm 30 . Arms 28 and 30 are conventional in the art of window operators. Arms 28 and 30 are secured by rivet 32 .
[0039] Arm 28 has a first end generally designated by reference numeral 34 and forms a portion of a worm wheel 36 , as is well known in the art. It will be noted that there is provided an aperture 33 in worm wheel 36 and which aperture 33 overlies aperture 26 . A shim 38 is placed between worm wheel 36 and base 18 .
[0040] An upper securement member 40 works in conjunction with a lower securement member 42 to secure arm 28 in position. In this regard, upper securement member 40 has a threaded recess which is designed to screwthreadedly engage with threads 44 on lower securement member 42 . In this arrangement, the lower securement member 42 , upon tightening the same, draws upper securement member 40 downwardly into position to maintain a secure connection therebetween.
[0041] A shaft 46 has a worm 48 formed at one end thereof. At the opposed end, there is provided a spur gear 50 and worm screw 57 which is designed to engage with a handle 51 .
[0042] Shaft 46 , at the end proximate worm 48 , has a recess 52 which is designed to receive a ball bearing 54 to allow for easy turning of shaft 46 . A thermal seal 56 is also provided to prevent the passage of air from the interior of operator 16 .
[0043] Operator 16 also includes a monocoque housing 58 which has two internally threaded cylinders 60 , 62 which are designed to receive screws 64 , 66 passing through post 22 and 24 to thereby mount the base 18 to the monocoque housing 58 .
[0044] Ideally, a sealing member 68 is provided for thermal sealing against sash 14 .
[0045] Turning to the embodiment of FIGS. 3A, 3B and 4 , there is illustrated a double arm operator and which double arm operator is generally designated by reference numeral 100 . Double arm operator 100 includes a handle 102 and a base 104 which has a plurality of mounting apertures 106 .
[0046] A first arm 108 includes a mounting aperture 110 formed therein. A second arm 112 has a second arm extension 114 as in the previously described embodiment. A mounting aperture 116 is formed in the center of worm wheel 118 . A shim 120 is mounted between second arm 112 and first arm 108 . As in the previously described embodiment, there is provided an upper securement member 122 and a lower securement member 124 which are screwthreadedly engaged with each other.
[0047] In this embodiment, there is provided a second worm wheel 126 while as may be seen in FIG. 3B , there is provided an aperture 128 for mounting of worm wheel 126 . In this regard, it may be mounted in the same manner as previously described with use of upper and lower securement members.
[0048] As may be seen in FIG. 6 , in one embodiment of the present invention there is provided a plate 310 . A worm 312 operates in conjunction with worm gear 314 . An arm 316 is connected to worm gear 314 as in previously described embodiments.
[0049] There is also provided a pinion gear 318 and securement member 320 . Pinion gear 318 is designed to mesh with rack gear 322 .
[0050] The blade is formed of a plurality of blade members 326 and connectors 324 with plugs 328 . In this arrangement, a series of precut blade members 326 may be arranged to have the desired length. The length will vary upon the size of the window.
[0051] The track includes a corner component generally designated by reference numeral 334 . Corner component 334 has a base 336 and a pair of side walls 338 which are angled inwardly so as to retain the blade therein. Side walls 338 and base 336 form a channel 340 . Blade members 336 are serrated or have teeth 344 formed thereon.
[0052] Where a blade member 336 passes through corner 334 , there is provided an upper corner element 348 and a lower corner element 350 . Upper corner element 348 includes a center portion 352 which is arranged to press on a blade member 326 as it goes through the corner. As upper corner element 348 is formed of a low friction material, this assists in the blade moving around the corner.
[0053] As shown in FIGS. 10 and 11 , when utilizing an awning type window which is hinged on both sides, it is desirable to have a locking mechanism on each side. Naturally, it is further desired that a single motion be utilized for locking both sides. Still further, it is desirable that the locking movement be in the same direction—to lock the mechanism would move vertically upwardly and to unlock, would move vertically downwardly. According to an embodiment of the present invention, this is achieved by use of a reverser generally designated by reference numeral 356 . Reverser 356 has a housing 358 . A first blade member 360 extends to a first side. First blade member 360 has a base 362 and side walls 364 which have teeth 366 formed thereon. A portion of the blade has teeth and is operated by a rotatable cog wheel 368 . On the other side, there is provided a second blade member 360 ′ which also has a base 362 ′ and side walls 364 ′ with teeth 366 ′ engaging with teeth on rotatable cog wheel 368 .
[0054] In the embodiment shown as FIGS. 12A , B, C and 13 A, B, C and D, an arrangement is provided whereby the window must be unlocked before it can be opened. To this end, there is provided a handle 376 mounted to a base 378 in a pivotable manner. Housing 380 has a recess 382 therein such that the handle, which is used to open or close the window, can be moved from a first position wherein it is retained partially within recess 382 in housing 380 . An actuator handle 384 , when used to lock the window, is moved to the position illustrated in FIG. 12A . As indicated by arrow 386 , actuator handle 384 must be moved to unlock the window to gain access to handle 376 .
[0055] In the embodiment of FIG. 14 , there is provided a mechanism to maximize security if the locking mechanism is tampered with from the outside. A recess 390 is formed in pinion gear 318 . A cantilever spring 392 having a head 394 and legs 396 is arranged such that head 394 will fit within recess 390 when in a fully locked position. This provides additional resistance to tampering with the locking mechanism from the outside of the window while actuator handle 384 can provide sufficient leverage to easily move spring head 394 from recess 390 .
[0056] It will be understood that the above described embodiments are for purposes of illustration only and that changes and modifications may be made thereto without departing from the spirit and scope of the invention. | An operator for a window comprising a base designed to be secured to a window sash, an arm having first and second ends with the first end being secured to the base and a first end of the arm having a worm wheel formed thereon, a shaft having a worm operatively connected to the worm wheel, a handle secured to the shaft, a locking mechanism comprising a multipoint tie bar, and an actuator connected to a rack and pinion gear arrangement to move the multipoint tie bar between open and locked positions. The arrangement provides for a compact efficient design which includes a locking mechanism and an opening mechanism located at the same point. | 4 |
[0001] This is a national stage of PCT/AT08/000,029 filed Jan. 30, 2008 and published in German, which has a priority of Austrian no. G 100/2007 filed Feb. 16, 2007 and Austrian no. GM 727/2007 filed Dec. 3, 2007, hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to an adhesion-preventing or anti-adhesion or nonstick material for use in the removal of a part or subportion of a substantially flat or planar material layer which is bonded with at least one further substantially flat material layer in a bonding procedure by raising the temperature. The invention, moreover, relates to a method for removing a part or subportion of a substantially flat or planar material layer which is bonded with at least one further substantially flat or planar material layer in a bonding procedure by raising the temperature, a multilayer structure formed by at least two substantially flat material layers to be bonded with each other, and the use therefor, in particular, in the context of the production of a multilayer printed circuit board.
PRIOR ART
[0003] A method and an anti-adhesion or nonstick material of the kind mentioned-above can for example be taken from U.S. Pat. No. 6,245,382 B or DE 40 03 344 C, wherein in particular with DE 40 03 344 C it is aimed at providing a simple method for the production of a rigid-flexible printed circuit board.
[0004] Although the subsequent description at least partially refers to the production of a multilayer printed circuit board, it should be noted that the method according to the invention as well as the single- or multilayer structure according to the invention may be used in the most diverse applications, wherein it is aimed to remove a subportion or part from a substantially flat or planar material layer after bonding with at least one further substantially flat or planar material layer. In general, the present invention is applicable in connection with multilayer structures in which, after the production of a multilayer structure, a subportion is to be stripped, or one of the layers is to be removed. In this context, complex methods and constructions are, for instance, known, which, in particular, on account of the preconfectioning of at least one bonding layer used to bond the material layers to be bonded and the high operation expenditures involved as well as the accordingly high expenditures required for the subsequent proper orientation or registration of the material layers to be bonded, aim to strip or remove partial portions or subportions from such material layers after bonding. The substantially flat material layers may, for instance, be comprised of paper-like or cardboard-like layers or elements to be bonded, substantially plate-shaped or sheet-shaped element such as, e.g., foils, sheets or metal plates or the like. In the context of bonding substantially flat or plate-shape materials, it is, for instance, known, in particular with a view to an optionally subsequently required removal of at least a subportion thereof, to accordingly preconfection foils having adhesive properties such that subportions of the foils which, during a bonding procedure, are to ensure the adhesion of the material layers to be bonded are provided with recesses. In addition to substantially continuous adhesive foils, preconfectioned separation foils may alternatively be used as a function of the subportion to be subsequently removed. It is immediately apparent that the preconfectioning of such bonding foils or adhesive foils and/or separation foils involves accordingly high expenditures and, in addition, makes accordingly high demands on the registration and orientation of the material layers to be bonded via the interposition of such, in particular preconfectioned, foils.
[0005] In the context of the production of multilayer electronic components and, in particular, multilayer printed circuit boards, the design of such electronic components, which has increased in complexity during the past years, has generally led to an increase in the number of bonding points between active components and components of a printed circuit board, wherein the increasing reduction of size has, at the same time, entrained a reduction of the distance between such bonding points. In the context of the production of printed circuit boards, the disentanglement of such component bonding points by microvias through several circuit board layers in so-called high density interbonds (HDI) has been proposed.
[0006] In addition to an increase in the complexity of the design and construction of printed circuit boards and the miniaturization involved, further requirements with a view to providing foldable or bendable bonds in a circuit board have come up, which have led to the development of a hybrid technology and the use of so-called rigid-flexible printed circuit boards. Such rigid-flexible printed circuit boards comprising rigid portions or subportions of the printed circuit board as well as flexible portions bonding such rigid portions, have enhanced reliability, offered other or additional options of freedom in terms of design and construction, and enabled further miniaturization.
[0007] For the production of such rigid-flexible printed circuit boards, bonding layers corresponding with the rigid and flexible portions of a circuit board and made of dielectric materials are to be provided between said portions, whereby the arrangement of appropriate sheet-shaped layers or films which, for instance by heat treatment, cause the bonding of circuit board rigid and flexible portions to be bonded will usually result in comparatively thick layers. Such thick layers not only counteract the intended miniaturization in the fabrication of multilayer circuit boards, but also entail losses of the registering accuracy required for subsequent laser borehole geometries for the formation of microvias and accordingly narrowly spaced-apart connection or bonding sites. Such thick, known layers of non-conductive material, or dielectric layers, moreover, involve additional processing or process steps and/or more complex designs for the production of the connections required between the rigid and flexible portions of circuit boards, since, in particular, the appropriate preconfectioning or formatting is to be performed as a function of the subsequent division of the rigid portions of the printed circuit board.
SUMMARY OF THE INVENTION
[0008] While avoiding the problems of the above-mentioned prior art regarding, in particular, the preconfectioning or formatting of bonding elements or foils, or separation foils, when producing a bond between at least two flat or planar material layers, the present invention aims to provide an anti-adhesion or nonstick material which is simple and reliable to produce and use and process. In addition, the invention aims to provide a method for removing a subportion of a substantially flat material layer as well as a multilayer structure and its use, which are accordingly simple and reliable to perform and produce, respectively, in particular by using such an anti-adhesion material according to the invention.
[0009] To solve these objects, an anti-adhesion or nonstick material of the initially defined kind is substantially characterized in that the anti-adhesion material comprises a difference in polarity relative to the adjoining substantially flat or planar material layers. It is thereby feasible in a simple and reliable manner to prevent the material layers to be bonded from adhering in the region of the subportion to be subsequently removed, so that expensive confectioning and positioning steps as required in the prior art, for instance when using the respective adhesive foils or separation foils, can be obviated, wherein the anti-adhesion material according to the invention can be applied or arranged in a simple and reliable manner as a function of the subportion or part to be subsequently removed. The prevention of an adherence, or separation effect, is substantially based on the incompatibility, and difference in polarity, between the material of the adjoining, substantially flat material layers and the anti-adhesion material. In this respect, a nonpolar compound should possibly be used for the anti-adhesion material or adhesion-preventing material, wherein, for instance, waxes of natural or synthetic origin are suitable for this purpose as will be explained in more detail below.
[0010] In order to enable the particularly simple and reliable processing of the adhesion-preventing material or anti-adhesion material, it is provided according to a preferred embodiment that the anti-adhesion material comprises a separation component, a binder and a solvent. The separation component ensures that an adhesion in the region of the subportion to be subsequently removed, between the material layers to be bonded will be reliably prevented. The binder, in particular, serves to fix the anti-adhesion material to the support, or one of the material layers to be bonded, during the bonding procedure and adjust a rheology which will enable a perfect and problem-free application. Moreover, such a binder will, for instance, migrate into the material of an adjoining flat material layer so as to further enhance the separation effect, or adherence-preventing action. The solvent, for instance, serves to enable the simple and reliable processing of the anti-adhesion material.
[0011] In this context, it is proposed according to a further preferred embodiment that the anti-adhesion material comprises hydrocarbon waxes and oils, waxes and oils based on polyethylene or polypropylene compounds, waxes and oils based on organic polyfluoro-compounds, esters of fatty acids and alcohols or polyamides, silicoorganic compounds and/or mixtures thereof. Such waxes and oils, as a function of the purpose of use, are available in large numbers in different configurations and with different chemical and physical properties so as to be selectable as a function of the material layers to be bonded. The hydrocarbon waxes and oils may be of synthetic or natural origin such as, e.g., paraffins. In addition to, in particular, synthetic waxes and oils based on polyethylene or polypropylene compounds, modifications of this product group may also be employed. As far as synthetic waxes and oils based on polyfluoro-organic compounds or organic polyfluoro-compounds are concerned, PTFE may be cited as an example. Waxes and oils based on esters of fatty acids, and mono- or polyvalent alcohols, may be of synthetic or natural origin such as, e.g., palmitic or stearic acid derivatives, carnauba wax or the like. Examples of silicoorganic compounds, for instance, include silicone and silicone oil.
[0012] To enable the simple application of the anti-adhesion material according to the invention as well as the reliable formation of a portion to be kept free from bonding between the material layers to be bonded, which is provided in the region of the subportion to be subsequently removed, it is proposed according to a further preferred embodiment that the anti-adhesion material is comprised of a paste. Such a paste or waxy paste can, in a simple and reliable manner and accordingly precisely as a function of the subsequent separation or removal of the subportion, be reliably and precisely applied on or to one of the material layers to be bonded so as to enable, at an accordingly simplified process control, after bonding of the material layers to be bonded, the simple removal of said subportion, since in the region of the subportion to be subsequently removed an accordingly unbonded area, or portion free of an adhering bond between the material layers, will be provided by the application of the adhesion-preventing material in the form of a waxy paste.
[0013] For a particularly simple and position-precise application of the portion to be kept free from bonding with a view to the subsequent removal of a subportion of one of the material layers, it is proposed according to a further preferred embodiment that the anti-adhesion material is applicable by a printing process and, in particular, screen-printing, stencil-printing, offset printing, flexoprinting, tampon printing, ink-jet printing or the like.
[0014] For simple processing, such waxy pastes can, for instance, be applied in the form of micro-dispersions in polar or nonpolar organic solvents.
[0015] In order to facilitate the application and handling, in particular, of the material layers to be bonded, it is, moreover, proposed that the anti-adhesion material is provided with inorganic and/or organic fillers and additives, as in correspondence with a further preferred embodiment.
[0016] In order to obtain the desired separation effect by non-bonding through the application of the anti-adhesion material, it is proposed according to a further preferred embodiment that the anti-adhesion material has a softening or melting point of at least 100° C. and, in particular, 120° C. Such a high softening or melting point of the layer of anti-adhesion material will, for instance in the production of a printed circuit board, cause the additionally applied adhesive layers to cure during a lamination procedure and, at a further increase in temperature during the bonding or pressing cycle, the anti-adhesion material or adhesion preventing material according to the invention to liquefy, thus safeguarding that the non-bond area provided by the anti-adhesion material and required to enable the subsequent removal of the subportion will be reliably maintained. During the bonding procedure, the anti-adhesion material, by the formation of a liquid layer in the subportion to be subsequently removed will prevent continuous bonding, for instance gluing together, of the material layers to be bonded.
[0017] In order to obtain desiredly thin layer thicknesses while maintaining the bond-free area of the subportion to be removed, or preventing the adherence of the same, as provided by the invention, it is proposed according to a further preferred embodiment that the anti-adhesion material is applicable in a layer thickness of less than 25 μm and, in particular, less than 15 μm. Yet, layer thicknesses of up to 50 μm or, optionally, even more may also be envisaged.
[0018] In the context of providing a comparatively high softening point for the anti-adhesion material according to the invention, which comprises a solvent amongst others, it is proposed according to a further preferred embodiment that the solvent has a boiling point of less than 220° C. and, in particular, about 180 to 200° C. This will ensure that no problems, for instance, in terms of premature drying will occur during the application of the anti-adhesion material. Such a boiling point will, moreover, ensure that the solvent will be substantially completely removed or evaporated at a further increase in temperature.
[0019] For a particularly simple and reliable formulation of the anti-adhesion material according to the invention, it is proposed according to a further preferred embodiment that a cellulose derivative or a water-soluble and, preferably, alkali-saponifiable compound is contained as said binder.
[0020] To solve the above-mentioned objects, a method of the initially defined kind is, moreover, substantially characterized in that, in the region of the subsequent removal of the subportion or part, a portion kept free from direct bonding between the material layers is provided by applying an anti-adhesion or nonstick material according to the invention or a preferred embodiment of the same. By providing according to the invention, in the region of the subsequent division or removal of a subportion, a bond-free area by the application or arrangement of the anti-adhesion material according to the invention to prevent, in particular, the adherence of the subportion to be subsequently removed to the further material layer to be provided, a subsequent division of the material layer including the subportion to be removed can be reliably performed without observing extremely precise tolerances for the realization of the dividing step, for instance in respect to the division depth, for the subsequent removal of said subportion. By the provision of a bond-free area, it has, moreover, become possible to renounce, in particular, any preconfectioning and/or formatting of bonding-enabling layers in the region of the subsequent division and removal of the subportion such that preparation steps for the production or preparation of the material layers to be arranged and bonded, and of a layer to be used for bonding, will be facilitated. Due to the fact that the preconfectioning of an adhesive layer or bonding layer, or layer to be provided, can be renounced in the region of the subsequent division or removal of a subportion, it will, moreover, be feasible to even do with thin or thinner such intermediate layers or bonding layers of an adhesion-preventing material or anti-adhesion material between the metal layers to be bonded. It is, thus, feasible according to the invention to use substantially continuous material layers, wherein the adhesion-preventing portion for the formation of the bond-free area can be applied or provided in a simple manner.
[0021] In the context of the production of a printed circuit board, a miniaturization of such a printed circuit board and, in particular, a rigid-flexible printed circuit board will, in particular, be feasible by minimizing the overall printed circuit board to be produced, whereby even problems as described above in the context of the known prior art in respect to the registering accuracy when providing thick layers when requiring the necessary preconfectioning or formatting of intermediate layers will be reliably avoided.
[0022] In order to enable particularly simple processing of the anti-adhesion material according to the invention, it is proposed according to a preferred embodiment of the method according to the invention that the anti-adhesion material is subjected to a drying and/or curing process after its application. Such a drying and/or curing process can be performed as a function of the materials used for the anti-adhesion material and selected, in particular, in correspondence with the adjoining material layers.
[0023] In order to obtain desiredly thin layer thicknesses while maintaining the bond-free area of the subportion to be removed, or preventing the adherence of the same, as provided by the invention, it is proposed according to a further preferred embodiment that the anti-adhesion material is applied in a layer thickness of less than 25 μm and, in particular, less than 15 μm.
[0024] As already pointed out above several times, the method according to the invention, in particular, can be applied in a particularly beneficial manner in the production of a printed circuit board, in which context it is proposed according to a further preferred embodiment that the substantially flat material layers to be bonded are formed by layers of a multilayer printed circuit board.
[0025] In this context, it is, moreover, preferably proposed that the material layers to be bonded are bonded by a lamination process, whereby special requirements, particularly in connection with the production of a multilayer printed circuit board and the materials employed in the production of such a multilayer printed circuit board, can be taken into account due to the above-mentioned material properties of the anti-adhesion material according to the invention, for instance in terms of the softening point of the anti-adhesion material as well as the boiling point of the solvent contained in said material.
[0026] For a particularly reliable and simple removal or separation of the subportion to be removed after having bonded the flat material layers to be bonded, it is, moreover, proposed that edge regions of the subportion to be removed are defined and/or removed by milling, scratching, cutting, in particular laser-cutting, as in correspondence with a further preferred embodiment of the method according to the invention. Such milling, scratching, cutting or the like procedures can be accordingly precisely and reliably performed in conformation with the flat materials to be bonded, wherein even with the use of materials having slight thicknesses such as, for instance, in the context of the production of a multilayer printed circuit board, an accordingly precise and reliable performance of the dividing procedure will be feasible. As already pointed out above, the requirements in terms of tolerances to be observed, will, moreover, be accordingly reduced by the adhesion-prevention material layer.
[0027] To solve the above-mentioned objects, a multilayer structure of the initially defined kind is, moreover, essentially characterized in that, in the region of a subportion to be removed after having realized the bond between the material layers, an area kept free from direct bonding between the material layers to be bonded is provided by the application of an anti-adhesion material according to the invention or a preferred embodiment of the same. It is, thus, readily feasible to provide a bond between at least two substantially flat material layers, with the subsequent removal of a subportion to be removed being enabled by the provision and simple application of an adhesion-preventing material or anti-adhesion material. In addition, an enhanced orientation or registration of the substantially flat material layers to be bonded will be ensured.
[0028] For the simple formation of the bond-free area in the region of the subportion to be subsequently removed, of the substantially flat material layers to be bonded, it is proposed that the anti-adhesion material is comprised of a wax paste.
[0029] In order to achieve accordingly thin overall thicknesses of the multilayer structure according to the invention, it is, moreover, proposed that the anti-adhesion material is applied in a layer thickness of less than 25 μm and, in particular, less than 15 μm, as in correspondence with a further preferred embodiment of the multilayer structure according to the invention.
[0030] According to a further preferred embodiment, it is, moreover, proposed that the substantially flat material layers to be bonded are formed by layers of a multilayer printed circuit board.
[0031] A particularly reliable bond will be provided in that the material layers to be bonded are bonded by a lamination process.
[0032] The reliable removal of the subportion to be removed after bonding of the substantially flat material layers to be bonded will, moreover, be achieved in that edge regions of the subportion to be removed are definable and/or removable by milling, scratching, cutting, in particular laser-cutting, as in correspondence with a further preferred embodiment of the multilayer structure according to the invention.
[0033] As already pointed out several times, it is, moreover, proposed according to the invention that the anti-adhesion material according to the invention or a preferred embodiment of the same and/or the method according to the invention or a preferred embodiment of the same and/or the multilayer structure according to the invention or a preferred embodiment of the same are used for the production of a multilayer printed circuit board.
[0034] In particular, in the context of such a use according to the invention, it is, moreover, proposed in a preferred manner to use the method according to the invention, or the multilayer structure according to the invention, for the production of cavities, in particular three-dimensional cavities, in a printed circuit board.
[0035] Further preferred uses of the method according to the invention and/or the multilayer structure according to the invention include the production of at least one channel in a printed circuit board, a bond-free area for the production of cavities, in particular three-dimensional cavities, in a printed circuit board, the production of offset and/or stepped subportions of a printed circuit board, the non-bonding of at least one element, in particular registering element, in the interior or within inner layers of a multilayer printed circuit board, and/or the production of a rigid-flexible printed circuit board.
SHORT DESCRIPTION OF THE DRAWINGS
[0036] In the following, the invention will be explained in more detail by way of exemplary embodiments schematically illustrated in the accompanying drawing, of the method according to the invention for producing a multilayer structure according to the invention by using the anti-adhesion material according to the invention.
[0037] Therein:
[0038] FIG. 1 is a schematic section through a first embodiment of a flat material layer of a multilayer structure to be produced according to the invention, in the form of a rigid portion of a rigid-flexible printed circuit board as a multilayer structure according to the invention;
[0039] FIG. 2 , in an illustration similar to that of FIG. 1 , illustrates a section through the rigid portion of a rigid-flexible printed circuit board, wherein milling edges are provided in the region of a subsequent division of the rigid portion subportion to be removed;
[0040] FIG. 3 , in an illustration similar to those of FIGS. 1 and 2 , depicts a section through the rigid portion of a rigid-flexible printed circuit board, wherein an anti-adhesion material according to the invention is provided or applied in the region of the subsequent division as well as the milling edges, for the formation of a bond-free area to prevent direct bonding between the substantially flat material layers formed by the rigid portion and the flexible portion of the printed circuit board;
[0041] FIG. 4 illustrates another section again similar to those of the preceding Figures, wherein a layer of non-conductive or dielectric material and a flexible portion of the rigid-flexible printed circuit board as a second substantially flat material layer are arranged on, or fixed to, the rigid portion of the first material layer;
[0042] FIG. 5 in a further similar section depicts the multilayer structure according to the invention in the form of a rigid-flexible printed circuit board after the division of the rigid portion;
[0043] FIG. 6 is a schematic section through a modified embodiment of a substantially flat material layer of a printed circuit board as a multilayer structure according to the invention to be produced by the method of the invention;
[0044] FIG. 7 depicts a schematic section through the flat material layer illustrated in FIG. 6 , with a layer of an adhesion-preventing material or anti-adhesion material according to the invention being applied;
[0045] FIG. 8 depicts schematic section through the flat material layer illustrated in FIGS. 6 and 7 , which is bonded with at least one further flat material layer to produce a multilayer printed circuit board as a multilayer structure according to the invention,
[0046] FIG. 9 , in an illustration similar to that of FIG. 8 , depicts a schematic section through the subportion of the multilayer structure to be subsequently removed, which is delimited or defined by cutting; and
[0047] FIG. 10 is an illustration similar to that of FIG. 9 , with the cut or delimited subportion being removed.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0048] A first embodiment of a multilayer structure according to the invention, which is produced as a rigid-flexible printed circuit board using the method according to the invention and an anti-adhesion material according to the invention, is described with reference to FIGS. 1 to 5 .
[0049] FIG. 1 is a schematic illustration of a rigid, multilayer portion 1 as a first substantially flat or planar material layer of a rigid-flexible printed circuit board to be subsequently produced as a multilayer structure. Individual metal or copper layers 2 are, for instance, separated by prepreg layers 3 and a core 4 . Connections between the individual copper layers 2 are indicated via microvias 5 and passages 6 , respectively.
[0050] For the production of a rigid-flexible printed circuit board, milling edges 7 are formed in the region of a subsequent division of the rigid multilayer portion 1 of the rigid-flexible printed circuit board to be produced, as indicated in FIG. 2 .
[0051] In order to provide a bond-free area, or prevent direct bonding between the printed circuit board rigid portion 1 to be subsequently divided and a layer of non-conductive or dielectric material to be provided and arranged as a second substantially flat material layer of the printed circuit board for bonding with a flexible portion, a material preventing such an adhesion or anti-adhesion material 8 is provided following the formation of the milling edges 7 , in the region of the subsequent division and in the channels or grooves formed by the milling edges 7 in the embodiment depicted in FIGS. 1 to 5 . The anti-adhesion or nonstick material may, for instance, be comprised of a waxy paste 8 , such a waxy paste 8 being applied, or introduced, in the region of the subsequent division as well as into the milling edges 7 by simple method steps, e.g. by a printing process, in particular screen-printing or stencil-printing. Depending on the material 8 used, or the waxy paste, a drying and/or curing process may be provided following the application of the material or paste 8 .
[0052] The material or paste 8 can be applied in the form of a micro-dispersion in polar or nonpolar organic solvents. For the simple processability and for simple handling, it is, moreover, provided that the paste 8 is, for instance, comprised of polyethylene waxes, polypropylene waxes, Teflon-based waxes and/or mixtures thereof.
[0053] To further enhance the processability, it may, moreover, be contemplated that the paste 8 is provided with inorganic and/or organic fillers and/or additives.
[0054] In order to achieve accordingly thin layer thicknesses or overall thicknesses of the rigid-flexible printed circuit board to be produced, it is, moreover, provided that the paste or anti-adhesion material 8 is applied in a layer thickness of less than 25 μm and, in particular, less than 15 μm in the region of the subsequent division.
[0055] Further exemplary embodiments of an anti-adhesion material to be used will be given below.
[0056] While, in the embodiment represented in FIGS. 1 to 5 , the formation of milling edges 7 is provided prior to the application of the anti-adhesion material or paste 8 , the paste 8 may alternatively be applied in the region of the subsequent division of the rigid and, in particular, multilayer porion of the printed circuit board, after which the milling edges 7 will subsequently pass through the applied material 8 .
[0057] As depicted in FIG. 4 , the application of the anti-adhesion material or waxy paste 8 in the region of the subsequent division as well as the milling edges 7 is followed by the application or arrangement of a bonding layer 9 of non-conductive or dielectric material, said bonding layer 9 being, for instance, comprised of a foil known per se, for instance a prepreg or RCC foil, or even a liquid dielectric material. Following the layer 9 of non-conductive or dielectric material, a flexible subportion 10 of the rigid-flexible printed circuit board to be produced is indicated, wherein the flexible portion 10 of the rigid-flexible printed circuit board to be produced, like the rigid portion 1 , may be comprised of several layers.
[0058] By the arrangement of the anti-adhesion material 8 or waxy paste, preconfectioning and/or formatting for the non-conductive or dielectric material layer 9 to be provided can be renounced, in particular, in the region of the subsequent division in the region of the milling edges 7 such that preparation steps for the non-conductive or dielectric material layer 9 to be provided will be simplified or reduced.
[0059] By providing the bond-free area in the region of the application of the material 8 on the rigid portion 1 of the rigid-flexible printed circuit board to be produced, thinner layer thicknesses of the layer 9 will, moreover, do, said thickness being, for instance, selected to be less than 50 μm and, in particular, 40 μm or less. The provision of such thin layer thicknesses of the layer of non-conductive material to be arranged between the rigid portion 1 and the flexible portion 10 of the rigid-flexible printed circuit board to be produced will not only promote a reduction of the overall thickness of the rigid-flexible printed circuit board to be produced, but the positioning and registering accuracy of the portions to be bonded and of subsequent passages or microvias will also be enhanced.
[0060] FIG. 5 represents a section through the rigid-flexible printed circuit board formed by the rigid portion 1 and the flexible portion 10 as a multilayer structure, wherein a division 11 has been made between the then separated rigid subportions 12 and 13 in the region of the milling edges 7 . Said division 11 constitutes a subportion to be subsequently removed after bonding of the flat material layers. It is, moreover, indicated that a connection between the flexible portion 10 of the printed circuit board and the then separated rigid subportions 12 and 13 is achievable by additional microvias or passages 14 .
[0061] As is further apparent from the illustration according to FIG. 5 , it is possible, without having to consider or observe very precise tolerances in terms of the cutting depth of the division or subportion 11 to be removed, to facilitate also the production of the division and, hence, subsequent method steps by providing the non-bonding surface, or preventing bonding, through the application of the anti-adhesion material 8 .
[0062] By the appropriate choice of the anti-adhesion material or waxy paste 8 and the layer 9 of non-conductive or dielectric material to be arranged between the rigid portion 1 , or subsequently separated rigid portions 12 and 13 , respectively, and the flexible portion 10 of the printed circuit board, it will be readily feasible to take into account legal limitations required when using specific hazardous substances in electric and electronic equipment.
[0063] By providing the bond-free area through the application of an anti-adhesion material or waxy paste 8 , simple method steps will do, in particular, in the preparation or production of the layer 9 to be arranged between the flexible portion 10 and the rigid portion 1 as well as in subsequent method steps for realizing the division.
[0064] By using thin layer thicknesses for bonding the flexible portion 10 as well as the rigid portion 1 , and the mutually separated rigid portions 12 and 13 , respectively, and the thus achievable thin layer thickness as well as the hence resulting improvements in the registering accuracy, it has, moreover, become possible to provide printed circuit boards with flexible layers 10 for highly complex components even in large formats, for instance in the production format of HDI circuit boards of more than 18×24 inch.
[0065] The embodiment of a multilayer rigid printed circuit board, or rigid portion 1 of a printed circuit board, which is depicted in FIGS. 1 to 5 , for illustration purposes merely represents a simplified example of such a multilayer printed circuit board as a multilayer structure, wherein also a larger number or plurality of, in particular, conductive layers 2 and feedthroughs via microvias 5 or passages 6 and 14 , respectively, may be employed as a function of the desired complexity of the component to be produced.
[0066] In the exemplary embodiment illustrated in FIGS. 6 to 10 , of a modified multilayer structure, again in the form of a multilayer printed circuit board to be produced, a structured core of such a printed circuit board is generally denoted by 20 , which core 20 comprises several layers with, in particular, the upper layer depicted in FIG. 6 being structured accordingly.
[0067] The core 20 , which is comprised of one or several layer(s) and constitutes a substantially flat material layer, in a subportion is subsequently provided with an adhesion-preventing material or anti-adhesion material 21 for bonding with further layers as additional substantially flat material layers, as illustrated in FIG. 7 , said anti-adhesion material being, for instance, applied by screen-printing.
[0068] Following the application of the adhesion-preventing material 21 on the substantially flat material layer formed by the core 20 as illustrated in FIG. 7 , bonding in a manner known per se, for instance by a lamination process, of the flat core 20 with a plurality of again substantially flat material layers 22 and 23 is effected, the subportion provided with the anti-adhesion material being again denoted by 21 in FIG. 8 . The flat material layer 23 illustrated in FIG. 8 may again be accordingly structured on its upper surface.
[0069] After the bonding procedure illustrated in FIG. 8 , between the plurality of substantially flat material layers 20 , 22 and 23 , a delimitation or definition of a subportion 25 of the substantially flat material layer 23 is effected, for instance, by cutting, in particular laser cutting, while forming cutting lines or impressions 24 , as is apparent from FIG. 9 . The anti-adhesion material 21 provided below the subportion 25 to be removed renders feasible in a simple manner, after the formation of the cutting line or delimiting impressions 24 , the simple and reliable removal of the subportion 25 , as is illustrated or indicated in FIG. 10 .
[0070] In the embodiment depicted in FIGS. 6 to 10 , additional layers are indicated between the individual substantially flat material layers, which additional layers are known as such in the context of the fabrication of a multilayer printed circuit board and, therefore, not discussed in detail.
[0071] Also from the embodiment according to FIGS. 6 to 10 , it is clearly apparent that the bond-free area provided in the context of bonding substantially flat materials or material layers 20 , 22 and 23 by applying an anti-adhesion material comprised, for instance, of a wax paste will subsequently allow for the simple and reliable removal of subportions 25 of at least one substantially flat layer 23 to be bonded therewith.
[0072] The cutting and, for instance, laser cutting operation illustrated and discussed in FIG. 9 may, for instance, be replaced with a milling operation as described in the embodiment according to FIGS. 1 to 5 , or by scratching or a similar dividing operation of the at least one material layer 23 .
[0073] From the embodiment according to FIGS. 6 to 10 , it is apparent that a cavity 26 and, in particular, three-dimensional cavity can, for instance, be created in subportions or individual layers of a multilayer printed circuit board by removing a subportion 25 .
[0074] It is, moreover, possible to use such a cavity 26 formed by the removal of the subportion or element 25 for the subsequent arrangement of separated elements in interior regions or inner layers of a multilayer printed circuit board.
[0075] In addition, the removal of subportions allows for the fabrication of a printed circuit board with offset and/or stepped subportions for special applications.
[0076] The adhesion-prevention material or anti-adhesion material 8 and 21 , respectively, besides the materials mentioned in the above-described embodiments, may, for instance, also comprise hydrocarbon waxes and oils, waxes and oils based on polyethylene or polypropylene compounds, waxes and oils based on organic polyfluoro compounds, esters of fatty acids and alcohols or polyamides, silicoorganic compounds and/or mixtures thereof.
[0077] Instead of forming a multilayer structure of a multilayer printed circuit board, as disclosed in the above-described exemplary embodiments, such multilayer structures may also be formed by materials different from the materials used for the production of a printed circuit board, such as, e.g., foils or sheet- or plate-shaped materials. After or during the simple and reliable bonding of substantially flat material layers, wherein the preconfectioning or formatting of, for instance, adhesive or bonding foils is renounced for the bonding layer, it is possible, following such a simplified bonding of substantially continuous material layers, to simply and reliably remove subportions by providing or applying the anti-adhesion material 8 or 21 , respectively.
[0078] In addition to the printing methods, e.g. screen-printing, mentioned in the above exemplary embodiments for the application of the anti-adhesion material 8 or 21 , respectively, offset printing, flexoprinting, tampon printing, ink-jet printing or the like may be provided or used, in particular, as a function of the nature of the anti-adhesion material.
[0079] For the reliable separation or removal of the portion 11 or 25 , respectively, to be subsequently removed, it is to be taken care, in particular, when using the anti-adhesion material 8 or 21 , particularly in the form of a waxy paste, that this anti-adhesion material exhibits an appropriate difference in polarity as well as an incompatibility with the adjoining substantially flat material layer(s).
[0080] In the context of the production of a printed circuit board, polarity differences and incompatibilities with epoxy resins, phenolic resins and copper as frequently used layers of a multilayer printed circuit board are, for instance, to be taken into account.
[0081] By the option provided by the invention, of a structured application of the anti-adhesion material 8 or 21 , subsequent methods steps, in particular in connection with the removal of subsequently removable subportions 11 or 25 of a multilayer structure, will be facilitated in a simple manner.
[0082] By using, for instance, an anti-adhesion material layer 8 or 21 which is applicable by simple printing techniques, formatting and confectioning techniques as are provided in the prior art, for instance for separation foils, can be obviated.
[0083] When using a waxy paste for the anti-adhesion material 8 or 21 , it is, moreover, advantageous that residues of the anti-adhesion material 8 or 21 optionally remaining after the removal of, for instance, subportion 11 or 25 , can again be removed in a simple and reliable and, in particular, complete manner.
[0084] Such a removal of the anti-adhesion material 8 or 21 after the removal of subportion 11 or 25 , may, for instance, be effected by the aid of wet-chemically or mechanically abrasive methods or even lasers so as to ensure the complete removal of said material 8 to 21 . After having removed the material 8 to 21 , structures located below said material 8 , such as, e.g., pads, conductor tracks, blind-hole bores etc. may be used for contacting further components.
[0085] In particular, in the context of the production or processing of printed circuit boards, non-bonding or the provision of an anti-adhesion material 8 or 21 will enable the formation of a space 26 for additional components, for instance by a local thickness reduction, as already mentioned above. Such a provision of a space 26 , in particular and substantially in the interior of such a multilayer printed circuit board will, moreover, enable a reduction of the overall thickness of such a multilayer printed circuit board by the embedment of such components so as to take into account the requirements of a miniaturization of printed circuit boards.
[0086] By a local thickness reduction, it has, for instance, become possible to contact additional components to be arranged in the region of the removed subportion 25 , in particular after the removal of the optionally remaining anti-adhesion material 21 , as indicated in FIG. 10 , directly on the bottom of such a recess or cavity 26 . In doing so, it is, for instance, possible in a simple manner to arrange the respective contact elements or conductive structures, in case of the material layer 20 provided in FIG. 6 , in the region of the cavity 26 to be subsequently produced, as is illustrated in FIG. 10 .
[0087] As already pointed out above, the subsequent removal of subportions 25 while forming cavities 26 will also render feasible the provision of accordingly three-dimensional open or optionally closed cavities, wherein it is feasible, for instance when departing from the condition represented in FIG. 10 , to provide further layers of a multilayer printed circuit board.
[0088] By the appropriate choice or arrangement of the anti-adhesion material 8 to 21 , it is, moreover, possible to enable the formation of cavities 26 over several layers of such a multilayer conductor structure, as is, for instance, indicated in FIG. 5 with reference to the first embodiment.
[0089] In the context of the production of printed circuit boards, it is, thus, for instance, also possible, by removing subportions 25 , to provide an accordingly simplified non-bonding of registering elements.
[0090] The formation of stepped or offset subportions, for instance, allows for the creation of interleaved or overlapping portions of a multilayer printed circuit board.
[0091] By the removal of subportions through the application of an adhesion-preventing material or anti-adhesion material 8 or 21 it will, moreover, for instance, be feasible to provide repair options of already existing or populated printed circuit boards with embedded components, if, for instance, an anti-adhesion material is accordingly provided as a precaution in the region of components optionally subject to high failure or damage rates so as to enable the repair of a printed circuit board by the removal of a subportion in the event of a defect of such a component rather than requiring its complete substitution, thus enabling the simple exchange of components and the simple provision of a multilayer structure comprised of at least two substantially flat material layers to be bonded.
[0092] In the following, several exemplary embodiments of the adhesion-preventing material or anti-adhesion material will be described.
Example 1
[0093] 50 g of an acrylic thickener were diluted with 370 g water, and 5.5 g 25% ammonia solution were added under stirring. The viscous varnish formed was used as a binder for the anti-adhesion material to be produced.
[0094] 200 g polyethylene wax powder were dispersed in 200 g of the above-prepared binder by the aid of a vacuum mixer. Such a formulation or anti-adhesion material is particularly suitable for being applied by screen-printing.
Example 2
[0095] Departing from a binder according to Example 1, an anti-adhesion material based on a polyethylene/carnauba wax mixture was produced in a manner similar to Example 1.
Example 3
[0096] As in Example 1, 50 g of an acrylic thickener were diluted with 370 g water to form a binder for use with oily or waxy components. Instead of adding n ammonia solution, this mixture was saponified with 2 g 20% soda lye.
[0097] An anti-adhesion material produced with such a binder exhibits an enhanced resolubility in a printing process.
Example 4
[0098] Departing from the binder according to Example 1, the binder was saponified with 5 g triethanolamine instead of adding an ammonia solution. An anti-adhesion material produced with such a binder likewise exhibits an enhanced resolubility in a printing process.
Example 5
[0099] A binder mixture based on a solvent was prepared by dissolving 10.8 g ethylcellulose in 89.2 g ethoxypropanol. The viscous varnish formed was used as a binder for the production of anti-adhesion materials.
[0100] 40 g polyethylene wax powder were added to 160 g of the above-prepared binder and dispersed by the aid of a vacuum mixer.
[0101] Such an anti-adhesion material is suitable for being applied by a printing process, in particular screen-printing process, and, in particular, exhibits good rheological properties.
Example 6
[0102] A binder mixture based on a solvent was prepared by dissolving 36 g ethylcellulose in 384 g DPGMA (dipropyleneglycol methylether acetate). The viscous varnish formed was used as a binder for the production of anti-adhesion materials.
[0103] 180 g polyamide wax powder were dispersed in 420 g of the above-prepared varnish or binder by the aid of a vacuum mixer.
[0104] A formulation suitable for screen-printing and exhibiting good rheological properties, a good resolubility and printability as well as processability was obtained.
[0105] In order to enhance the visibility of the mixture, a dye, for instance 2 g of a soluble dye, e.g. Neozapon Blue 807, was added.
Example 7
[0106] The DPGMA used for the preparation of the binder was replaced with a naphthenically aromatic solvent.
[0107] The further formulation of the anti-adhesion material corresponds to that of Example 6.
Example 8
[0108] To produce an anti-adhesion material, a silicone resin was dissolved in an appropriate solvent.
Example 9
[0109] A thermally polymerizable silicone is directly used as an anti-adhesion material. | The invention relates to a nonstick material for use during removal of a part ( 11 ) of a substantially planar material layer ( 2 ) which is connected in a connecting step to at least on further, substantially planar material layer ( 9 ). According to the invention, the nonstick material ( 8 ) has a different polarity than the adjoining, substantially planar material layers ( 2, 9 ). The invention also relates to a method for removing a part ( 11 ) of a substantially planar material layer ( 2 ) which is connected in a connecting step to at least one further, substantially planar material layer ( 9 ), to a multilayer structure which consists of at least two substantially planar material layers ( 2, 9 ) to be interconnected, and to a use of the same, especially in a multilayer printed circuit board. | 2 |
BACKGROUND AND SUMMARY OF THE INVENTION
[0001] The invention relates to an airbag for a motor vehicle.
[0002] Such airbags are known and comprise an inflatable volume element for restraining occupants of the motor vehicle. The volume element comprises an inner space, into which a gaseous medium is introduced in order to move the volume element from a storage position into a restraint position to restrain the occupants. In order to guarantee optimum protection of occupants it is advantageous to inflate the volume element in a particularly short time. The faster it is inflated from its storage position into its restraint position the better the restraining function, as it can then take up a particularly large volume in an inner space of the motor vehicle in order to restrain the occupants.
[0003] Exemplary embodiments of the present invention are directed to an airbag for a motor vehicle that guarantees very good occupant protection.
[0004] In accordance with exemplary embodiments of the present invention an airbag for a motor vehicle comprises a housing and at least one restraint element comprising at least one receiving area for a gaseous medium, in particular air, said restraint element being movable in case of an accident-related force impact of the motor vehicle from a storage position within the housing into a restraint position through inflow of the medium into the receiving area. This means that the restraint element in the storage position is housed at least in areas in the housing, from which it can be moved from the storage position into the restraint position, in which the restraint element takes up a particularly large volume in an inner space of the motor vehicle in order to thus guarantee a very good restraint of occupants in case of an accident.
[0005] If at least one wall of the housing comprises at least one inflow opening for the medium, through which the medium can flow into the receiving area of the restraint element, the restraint element can thereby be moved particularly quickly, i.e., in a particularly short time, from its storage position into its restraint position. This means that the restraint element, in case of an accident, can take up a particularly large space or a particularly large volume in the inner space of the motor vehicle in order to protect occupants from collision with hard components causing injury. This has a particularly good effect upon occupant protection in the motor vehicle. The probability of the occupants suffering serious injuries is thus lower.
[0006] The restraint element can thereby be designed as a large, cohesive air sack that can be inflated by medium flowing into the receiving area for movement from the storage position into the restraint position. The medium can be actively blown into the receiving area, for example, by means of a gas generator. Alternatively, the medium can be sucked into the receiving area through the airbag unfolding upon movement from the storage position into the receiving position.
[0007] In addition, the restraint element can be formed by a lattice-like supporting structure, which is optionally provided with a shell at least in areas, whereby the receiving area is formed. The lattice-like supporting structure is thereby formed, for example, from a plurality of tube elements that also have a respective further receiving area, into which a medium can flow, wherein the medium is actively introduced, in particular blown, for example by means of a gas generator, into the respective further receiving area of the tube elements. Through the inflation of the tube elements the lattice-like supporting structure unfolds from the storage position into the restraint position and takes up a particularly large volume in the inner space of the motor vehicle. A so-called lattice-like bag with this supporting structure has the advantage that the receiving areas of the tube elements in sum have a smaller total volume to be inflated than the whole supporting structure ultimately takes up in the inner space. This lattice-like bag can thus take up a particularly high volume in the inner space, wherein a relatively small volume must be actively inflated. The receiving area of the airbag, formed by the supporting structure and possibly the shell, is thereby likewise filled with a gaseous medium, in particular ambient air, in order to achieve a good supporting effect of the lattice-like bag. Through the inflow opening in the wall of the housing the medium for this receiving area can flow particularly well and particularly rapidly into the receiving area of the restraint element formed by the supporting structure and optionally the shell, wherein this restraint element can likewise be moved particularly rapidly, i.e., in a short time, from the storage position into the restraint position. This is also particularly beneficial for occupant protection as the lattice-like bag can then prevent contact of the occupants with solid components that may cause injury in many cases. Through the inflow opening in the wall a possible under-pressure in the restraint element or in the receiving area, which could impede unfolding of the restraint element and thus lengthen an inflation time, can be prevented or at least reduced.
[0008] In an advantageous embodiment of the invention the airbag comprises at least one valve mechanism, by means of which a through-flow of the medium through the inflow opening can be adjusted. The valve mechanism preferably comprises at least one passage position exposing the inflow opening at least in areas, in which passage position the medium can flow into the receiving area. Likewise, the valve mechanism preferably has a closed position closing the inflow opening at least in areas, in which closed position an outflow of the medium from the receiving area is at least substantially prevented. Thus, the valve mechanism facilitates a particularly rapid movement of the restraint element from the storage position into the restraint position while also providing a very long useful life of the restraint element.
[0009] If, in case of an accident, an occupant comes into contact with the restraint element the receiving area is compressed, which causes or would cause initially an outflow of the medium from the receiving area. Due to the fact that the valve mechanism at least substantially prevents such an outflow in the closed position, the restraint element offers a certain useful life that depends upon a cross-section of the inflow opening that is opened or closed by the valve mechanism. The occupant can thus be protected in case of an accident and accelerations causing injuries can be reduced, as the medium can flow more slowly out of the receiving area than it can or could flow into the receiving area in case of movement of the restraint element into the restraint position. The inflow opening can also optionally be closed by the valve mechanism to such an extent that the medium can at least virtually no longer flow from the receiving area. It is understood that in case of a large cross-section of the inflow opening exposed by the valve mechanism more air can flow out of the receiving area. This results in a shorter useful life than in a case in which the valve mechanism exposes a smaller cross-section of the inflow opening. This results in a longer useful life of the restraint element.
[0010] The valve mechanism comprises for example at least one flap element, by means of which the inflow opening can be at least partially exposed or closed. The flap element is formed for example at least substantially as a film, as a textile layer and/or at least substantially from plastic. If the flap element exposes the inflow opening in the passage position it closes it at least in areas in the closed position, whereby it is supported for example on the wall of the housing delimiting the inflow opening. A failure of the flap element is thereby avoided.
[0011] It should be noted at this point that a ventilation, i.e., an inflow of the medium into the receiving area and possibly a valve mechanism, by means of which the through-flow of the medium through the inflow opening can be adjusted, is realized particularly in case of airbags without housing in such a way that at least one such inflow opening is integrated into a textile layer as a fabric of the airbag and thus directly into the restraint element, thus for example into the large cohesive airbag or the supporting structure or the shell thereof.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0012] Further advantages, features and details of the invention follow from the following description of a plurality of preferred embodiments and by reference to the drawings. The features and feature combinations mentioned above in the description and the features and feature combinations mentioned in the following description of the drawings and/or shown solely in the drawings can be used not only in the respectively indicated combination but also in other combinations or alone without going outside of the scope of the invention. The drawings show:
[0013] FIG. 1 a schematic cross-sectional view of an airbag for a motor vehicle with a housing, wherein walls of the housing comprise inflow openings for a gaseous medium;
[0014] FIG. 2 in a cut-out, a schematic and perspective cross-sectional view of a housing of an alternative embodiment of an airbag according to FIG. 1 ;
[0015] FIG. 3 in a cut-out, a schematic and perspective cross-sectional view of a further embodiment of a housing according to FIG. 2 ;
[0016] FIG. 4 in a cut-out, a schematic cross-sectional view of a further embodiment of an airbag according to FIG. 1 ;
[0017] FIG. 5 a schematic and perspective view of a housing for an airbag according to FIGS. 2 and 3 ;
[0018] FIG. 6 in a cut-out, a schematic and perspective view of a further embodiment of an airbag according to FIGS. 1 and 4 with the housing according to FIG. 5 ; and
[0019] FIG. 7 in a cut-out, a schematic and perspective view of a further embodiment of an airbag according to FIGS. 1 , 4 and 6 .
DETAILED DESCRIPTION
[0020] FIG. 1 shows an airbag 10 which comprises a housing 12 and a restraint element 14 . The restraint element 14 is thereby shown in FIG. 1 in a restraint position, in which it takes up a very large volume in an inner space of a motor vehicle, whereby the restraint element 14 can restrain occupants particularly well and thus protect them in most cases from impact against components. The restraint element 14 can thereby be moved from a storage position into the restraint position shown in FIG. 1 . In the storage position the restraint element 14 is received in the housing 12 . In order to ensure particularly good occupant protection the restraint element 14 can be moved particularly rapidly, i.e., in a particularly short time, from the storage position into the restraint position. In this connection the restraint element 14 comprises a receiving area 16 that is delimited in areas through the restraint element 14 and in areas through the housing 12 . Ambient air can flow into the receiving area 16 for movement of the restraint element 14 from the storage position into the restraint position. In order to ensure that a particularly large amount of ambient air can flow into the receiving area 16 in a particularly short time, both side walls 18 and 20 and also a bottom 22 of the housing 12 comprise inflow openings 24 , 26 and 28 , through which the ambient air can flow according to direction arrows 30 , 32 , 34 and 36 into the receiving area 16 .
[0021] In order to guarantee this inflow the airbag 10 comprises valve mechanisms 38 , 40 and 42 with respective valve flaps 44 , 46 , 48 and 50 . The valve mechanisms 38 , 40 and 42 have a closed position, in which an outflow of the ambient air contrary to the direction arrows 30 , 32 , 34 and 36 is at least substantially prevented. Likewise they have an open position shown in FIG. 1 , in which the inflow of air according to the direction arrows 30 , 32 , 34 and 36 is facilitated.
[0022] The valve mechanisms 38 , 40 and 42 thus facilitate not only an inflow of a particularly large quantity of ambient air in a particularly short time into the receiving area 16 but also facilitate a long and advantageous useful life of the restraint element 14 . This occurs because when an occupant impacts against the restraint element 10 the air in the receiving area 16 cannot flow or cannot flow unhindered out of the receiving area 16 contrary to the direction arrows 30 , 32 , 34 and 36 . Unhindered outflow of the ambient air via the inflow openings 24 , 26 and 28 is at least substantially prevented through the valve flaps 44 , 46 , 48 and 50 in the closed position.
[0023] As can be seen from FIG. 1 , the valve flaps 44 , 46 , 48 and 50 lift in the open position from the side walls 24 and 26 and the bottom 22 . If an inflow process of the ambient air into the receiving area has ended due to the unfolding restraint element 14 the valve flaps 44 , 46 , 48 and 50 again lie against the side walls 18 and 20 and the bottom 22 , as the valve flaps 44 , 46 , 48 , 50 are, for example, elastically formed and seek without force a state in which they lie against the side walls 24 and 26 and the bottom 22 and thus cover and close the inflow openings 24 , 26 and 28 . If an occupant contacts the restraint element 14 the inner pressure in the receiving area 16 increases and the valve flaps 44 , 46 , 48 and 50 are pressed even more greatly against the side walls 18 and 20 and the bottom 22 . A controlled and defined outflow of the ambient air out of the receiving area 16 , wherein a certain volume flow of the ambient air can flow out, is optionally desired in order to remove accelerations acting on the occupants. Such a volume flow is realized, for example, in that the inlet flows 24 , 26 and 28 are only covered in areas by the valve flaps 44 , 46 , 48 , 50 and these thus expose a certain cross-section of the inflow openings 24 , 26 and 28 . It is also possible to allow such an outflow of the ambient air out of the receiving area 16 through other openings, valve mechanisms or similar which are integrated for example into the restraint element 16 .
[0024] FIG. 2 shows an alternative embodiment of the housing 12 which is formed from a metal grid and thus provides a plurality of inflow openings for the ambient air. A valve function for the plurality of inflow openings according to the valve mechanisms 38 , 40 and 42 is provided, for example, by valve flaps which are formed from a film or films, fabric or fabrics or similar. It is also possible to form the housing 12 as a grill element or other perforated material. Plastic, sheet metal or other materials may be used
[0025] FIG. 3 shows a further embodiment of the housing 12 with the side walls 18 and 20 and the bottom 22 , wherein the side wall 20 comprises three inflow openings 26 , 26 ′ and 26 ″. The bottom 22 comprises four inflow openings 26 ′″, 26 ″″, 26 ′″″ and 26 ″″″. A particularly large amount of ambient air can thereby flow according to direction arrows 32 into the receiving area 16 .
[0026] FIG. 4 shows a further embodiment of the airbag 10 , wherein the airbag 10 comprises gas generators 52 and 54 . The restraint element 14 comprising the receiving area 16 is formed as a so-called lattice-like bag which comprises a lattice-like-like supporting structure that is provided with a shell formed as fabric. In other words, the receiving area 16 is delimited by the supporting structure and by the shell as well as by the housing 12 . The lattice-like supporting structure is in turn formed from a plurality of tube elements, which respectively comprise a receiving area, into which a gaseous medium is to flow or be blown in order to thus inflate the tube elements and thus the lattice-like supporting structure, whereby the restraint element 14 can be unfolded from the storage position received in the housing 12 into the restraint position shown in FIG. 4 . For particularly rapid inflation of the tube elements, and thus of the supporting structure, the gas generator 52 blows the gaseous medium into the further receiving areas of the tube elements. In order to further support the unfolding of the restraint element 14 the gas generator 54 blows a gaseous medium via an inflow opening 24 ′ of the side wall 20 of the housing 12 into the receiving area 16 .
[0027] FIG. 5 shows a further embodiment of the housing 12 that comprises the side walls 18 and 20 , the bottom 22 and end walls 56 and 58 . As can be seen from the drawing, a plurality of inflow openings 24 are provided respectively in the side walls 18 and 20 and in the end wall 56 , via which the gaseous medium, in particular ambient air, can flow into the receiving area 16 according to direction arrows 32 , whereby this can be seen from FIG. 6 .
[0028] FIG. 6 thereby shows a further embodiment of the airbag 10 with the housing 12 according to FIG. 5 . As can be seen in FIG. 6 , the bottom 22 of the housing 12 also comprises a plurality of inflow openings 24 , through which ambient air can flow into the receiving area 16 upon movement of the restraint element 14 from the storage position into the restraint position.
[0029] FIG. 7 shows a further embodiment of the airbag 10 that comprises the housing 12 and the restraint element 14 . Furthermore, the airbag 10 according to FIG. 4 comprises a gas generator 60 , by means of which a gaseous medium can be blown both into the receiving area 16 and also into the tube elements described in connection with the airbag according to FIG. 4 in order to inflate the supporting structure which is in particular lattice-like.
[0030] It is understood that the indications concerning the restraint element 14 according to FIG. 4 also apply similarly to the airbags 10 according to FIG. 1 , FIG. 6 and FIG. 7 and can be transferred and applied to their respective restraint elements 14 .
[0031] The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof. | An airbag for a motor vehicle, having a housing and at least one restraining element, which has at least one receptacle space for a gaseous medium, in particular air, and which can be moved, in the case of an accident-induced application of force to the motor vehicle, into a restraining position by the flowing of medium into the receptacle space from a storage position within the housing. At least one wall of the housing has at least one inflow opening for the medium. | 1 |
This application claims the benefit of U.S. provisional application No. 60/976,693, filed on Oct. 1, 2007, the entire disclosure of which is incorporated by reference.
References including various publications may be cited and discussed in the description of this invention. Any citation and/or discussion of such references is provided merely to clarify the description of the present invention and is not an admission that any such reference is “prior art” to the present invention. All references cited and discussed in this specification are incorporated herein by reference in their entirety and to the same extent as if each reference was individually incorporated by reference.
FIELD OF THE INVENTION
This invention relates to optical devices. More specifically, the present invention relates to collimated optical light source assemblies that produce a uniform white light.
BACKGROUND OF THE INVENTION
Entertainment, architectural and theater industries have applications which benefit from the creation of millions of colors for light painting, product enhancement, or special effect. Light emitting diodes of multiple primary wavelengths may be placed in the same cavity to produce such artistic color effects. Multiple cavities each comprised of multiple primaries may be arranged in such a way as to provide over 1000 lumens of red, green or blue light or any combination thereof. Secondary optics are required to throw light of many different colors over a long distance which requires light beams with minimum luminous intensity dispersion.
LED light engines with multi-primary emitters are known, for instance the 7-cavity Lamina Titan™ light engine. By themselves, light engines are historically difficult to both collimate to a narrow beam as well as achieve acceptable color uniformity. Traditional optics lack sufficient color uniformity enhancement features, and project regions of light with high discrete, non-homogenized intensities of the individual primary colors red, green and blue. Poor composite color uniformity is produced as a result, which is not desirable for some applications. A need exists for a combination of color uniformity enhancement and collimation features that direct the light from a multi-cavity, wide beam, e.g., 60 degree LED light array to a narrow beam of light or a beam characterized as comprising an intensity dispersion <15 deg at the half maximum of the intensity peak.
SUMMARY OF THE INVENTION
It is more acceptable to combine the light from multiple red/green/blue (“RGB”) primary color emitters arranged in a multi-cavity LED array to achieve a variable white color temperature from 2000° K. to 8000° K. for example. 2000° K. represents the blackbody temperature equivalent to a warm white color. 8000° K. is the blackbody temperature equivalent to a cool white or a white comprised of more blue. Preferably, in one embodiment of the invention the multi-cavity LED array includes seven LED cavities.
A device in accordance with an embodiment of the present invention preferably includes uniformity and collimation features shown in FIG. 1 , which may include one or more of the following:
1) A multi-cavity RGB LED array 1 ;
2) A reflecting cavity 2 with Lambertian scattering texture;
3) A Lenslet array 3 ;
4) Cone lens 4 ;
5) Reflector 5 ;
The combined effect of these uniformity and collimation features is to collimate a relatively wide-angle light beam emitted by an LED array into a relatively narrow-angle collimated light beam, such that color uniformity of the collimated light beam is enhanced.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more readily understood from the detailed description of exemplary embodiments presented below considered in conjunction with the accompanying drawings, in which:
FIG. 1 is a side schematic view of one embodiment of the RGB array collimation optical assembly of the present invention;
FIG. 2 is a top view of LED cavity placement; Each of the 6 peripheral cavities may contain 4 light emitting diodes of different primary wavelengths. The center cavity may have 1 each of red green and blue or other primary direct emission light emitting diode.
FIG. 3 is a ray trace diagram illustrating some of the light paths through the embodiment of FIG. 1 ;
FIG. 4 is a raytracing simulation plot of the relative intensity distribution as a function of angular dispersion.
FIG. 5 is a raytracing simulation plot of the illuminance distribution at a distance of 1 meter from the 7-cavity LED array source and optic.
FIG. 6 is a measured beam speckle pattern for R+G+B primary colors combined in correct ratio to produce a 6500° K. white color temperature equivalent in which the primary color combination produces approximately a white with 1931 x,y chromaticity coordinates of 0.3136 and 0.3237;
FIG. 7 is a measured beam speckle pattern for R+G+B primary colors combined in correct ratio to produce a 4750° K. white color temperature equivalent; in which the primary color combination produces a white with approximately 1931 x,y chromaticity coordinates in the vicinity of 0.3525 and 0.3574.
FIG. 8 is a measured beam speckle pattern for R+G+B primary colors combined in correct ratio to produce a 2850° K. white color temperature equivalent. The white chromaticity coordinates are near 0.4480 and 0.4076 respectively.
DETAILED DESCRIPTION OF THE INVENTION
Features of an embodiment of the present invention are shown in FIG. 1 . The reflecting cavity 2 , lenslet array 3 , cone lens 4 and reflector 5 are collectively referred to herein as the collimation optic. The collimation optic is used to decrease the intensity dispersion of a multi-cavity wide beam, e.g., 60 degree primary light engine cavity 1 in which the light emitters include light emitting diodes of different primary wavelengths, and wherein 60 degree refers to the beam angle of the light collectively emitted by the light engine cavities 1 . The multi-cavity 60 degree primary light engine may for example be the 7-cavity Lamina Titan™ light engine. A light engine with other than 7 cavities may also be used, so long as the beam angle of the emitted light, prior to any collimation optics, is approximately 60 degrees and the field angle is approximately 100 degrees.
Light exiting the LED array 1 disperses at approximately a 60 degree beam angle. The light then proceeds to reflecting cavity 2 which preferably has a barrel spline shape or elliptical cross-sectional shape with truncated entrance and exit planes. This desired cross-sectional shape is matched to the 60 degree beam width of the LED array 1 , and produces the greatest on-axis light intensity. However deviations from this cross-sectional shape are usable but will produce a reduced on-axis light intensity. For example, a deviation of 5% RMS from the prescribed cross-sectional shape can produce a 20% reduction in on-axis intensity. The reflecting cavity 2 has symmetry around the optical axis.
The interior surface of the reflector cavity 2 has a Lambertian texture. Intensity of light reflected from the interior of reflector cavity 2 varies with the cosine of the angle with respect to normal or 0 degree dispersion. A Lambertian scatterer redirects light with constant luminance when viewed at any angle. The Lambertian scatter texture randomizes the light of the primary colors in such a manner that light will emerge from the top of the reflector cavity 2 at an approximately equal intensity in all radial angles around the axis of rotation of the reflector cavity 2 .
Materials such as AMODEL™ polyphthalamide (PPA) from Solvay Advanced Polymers or equivalent can be molded into the desired cross-sectional shape with high reflectivity, and including the Lambertian scatter texture. Some loss is incurred in the randomization scatter process as such the enhancement of color uniformity has a trade-off. For example, although the Lambertian scatter texture of the reflector randomizes the light fields of the primary colors, it also directs light back towards the source which is undesirable. A reflector plate filling the spaces between the light cavities helps to recirculate some of this light back towards the exit aperture.
After scattering from the surface of the reflector cavity 2 , the light passes through a lenslet array 3 . The lenslet array 3 produces intermediate micro-images which further homogenize the light. The lenslet array 3 may include for instance a lenslet array as described in U.S. patent application Ser. No. 11/737,101 and provisional U.S. Patent Application No. 60/971,255, the entire contents of which are hereby incorporated herein in their entirety, and which are under a common obligation of assignment as with the present application.
After the light passes through the lenslet array 3 , it enters into and passes through the walls of an approximately cone-shaped lens 4 , which acts as a dispersing optic. A revolved polynomial is the preferred cross-sectional shape for the cone-shaped lens 4 because deviations in the shape from that of a revolved polynomial will produce unwanted artifacts or holes in the intensity pattern of the beam of light, i.e., a region or zone with reduced illuminance which the eye can detect.
However, changes to the revolved polynomial shape can also be tailored to produce different beam patterns when the reflector is changed to match, thus offering opportunities for different beam patterns. The eye perceives illuminance variations at 2.4*LOG(x,y) where x,y is the illuminance zone value. The x and y values represent the indices of vertical and horizontal spatial zones as referenced from the optical axis.
Light disperses through the side of the cone-shaped lens 4 for final collimation by the reflector 5 . A 4th-order polynomial may describe the shape of the cone-shaped dispersing lens, for instance: z=2E-05x^4+0.0007x^3−0.0056x^2+1.4405x+70.761. A 4th order polynomial which approximates a solution for the shape of the final collimation reflector is, for instance: z=8E-06x^4+0.0014x^3+0.0973x^2+1.8351x+49.335 in which z represents the forward light direction orthogonal to the source plane. A secondary lens is not recommended as the additional loss/collimation benefit ratio is too high. The final reflector preferably has an exit aperture which is larger than the input aperture or it will not collimate light. A confocal parabolic concentrator is commonly used to collimate light exiting from a finite source aperture.
By producing homogenous light from multiple primary color LED emitters housed in multiple cavities, the light intensity of each of the primary color emitters may be tuned to produce a variable white color temperature from warm to cool white. Other colors may also be produced as contained with the chroma triangle produced by the wavelengths of the primaries. However, colors of the LED die contained within the LED array 1 may be entirely arbitrary depending on the chroma polygon required, e.g., ultraviolet or infrared LEDs, or combinations of hybrid phosphor/direct emission sources is also possible so long as the reflective materials used in the assembly are tailored to efficiently reflect those wavelengths. Cavities containing only diode pumped phosphor may be interspersed with direct emission monochromatic primary colors.
The above description is presented to enable a person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the preferred embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Thus, this invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
This application may disclose several numerical range limitations. The polynomials enclosed are tailored specifically to the 60 degree intensity distribution pattern of the 7 cavity LED source array. Other ranges or variations from the polynomials disclosed may be used. The color uniformity enhancement features allow for the production of a tunable white temperature from 2000° K. to 8000° K. To produce a 6500° K. white the approximate ratio of red, green and blue light is 50% 457 nm 26% 525 nm, and 23% 625 nm. To produce 4750° K. white the approximate spectral power ratio of light is 40% 457 nm, 28% 525 nm, and 32% 625 nm red. To produce 2850° K. warm-white the spectral power ratio is approximately 16% 457 nm, 26% 525 nm, and 58% 625 nm light. The entire disclosure of the patents and publications referred in this application are hereby incorporated herein by reference. | This invention relates to optical devices. More specifically, the present invention relates to a collimated optical light source assembly that produces a uniform white light. Specifically, light from a multi-cavity RGB LED array is dispersed in a reflecting cavity having a Lambertian texture on the interior surface. The light is then emitted though a lenslet array and a cone lens which together further disperses the light emitted by the individual LEDs. The dispersed light is then collimated by a reflector. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to building systems and, more particularly, to a flexible building joint, providing a dynamic eave assembly for the structural intersection of angulated building members.
2. History of the Prior Art
The prior art is replete with structural building techniques which date back into technological antiquity. These structural systems generally incorporate a plurality of vertical, load bearing members, or wall sections, adapted for supporting siding disposed outwardly thereof and roof members thereabove. The support of a roof section necessitates the structural interengagement between the load bearing roof members, such as rafters and the wall members to comprise an eave. In many instances the structural roof members are angulated relative to the wall members for providing a slope to the roof surface facilitating the elimination of water from rain, snow and the like. Such designs are most typically seen in residential construction where pitched roofs have been commonplace for centuries. More conventional commercial construction has also adopted the "pitched roof" look in certain designs. Moreover, many commercial architectural innovations necessitate the utilization of angulated members for sloped side wall regions of buildings as well as roof sections thereon. The reasons vary but are basically founded upon the desire for distinction in both size and shape.
The introduction of angulated side and roof regions in commercial buildings has imposed additional structural and functional considerations. Conventional commercial construction generally utilizes a curtain wall system comprised of a plurality of planar glass sheets mounted upon vertical and horizontal mullions of generally hollow construction. The mullions are secured at various points to the structural members of the building and carry the weight of the glass panels disposed thereon as well as the responsibility for adequate sealing against water intrusion, drainage and structural integrity. Problems with the utilization of hollow mullions in angulated construction are, however, multifold. One problem is water intrusion, sealing and drainage. Another is purely structural, but even more serious. For example, the hollow mullions are fabricated from metal such as aluminum which is much more rigid than the wood which has been used for centuries in angulated roof/wall intersections. Loading of the roof from weight, rain, snow and the like will cause the angled roof members to deflect downwardly causing movement within the intersection. When the wall and roof members are mitered for mating engagement one to the other such deflection loads will cause high levels of compression across the inside edges of the contiguous mitered surfaces and separation forces across the outside mating region. The roof member in essence "pivots" against the vertical member. The inherent softness of wood generally used in residential construction absorbs this deflection load without serious damage to the joint. This is not the case when rigid metal sections are utilized because of the inherent structural rigidity and lack of elasticity to such compression loading. A welded mitered joint can, for example, ultimately manifest cracks along the weld due to the bending moment created through the rigid interengagement therebetween. The inside surfaces of the mitered joint resisting the deflection load serves as a pivot point, or fulcrum, across which the bending forces are amplified toward the outside intersection.
The stress problems of angular intersections have been addressed with gusset plates. The plates are usually conformed to the angle of the intersection and then bolted, welded, or riveted to the structural members. Although gusset plates have found widespread utility, they are both expensive and often unsightly. This has not been a favorite mode of expression because it can appear more like a riveter's handiwork than an architect's innovative design. Conventional attempts have thus been made to make the structural intersection joint not only practical but better looking than the present mode of expression. Current designs thus include a curved profile utilizing either clear plexiglass or a radius tempered insulated glass. The problem with plexiglass is that it is not scratch resistant, is difficult to maintain and often must be replaced within a short period of time due to wear. The radius tempered glass whether of the insulated or noninsulated variety is far more permanent, but is extremely expensive. This creates numerous sealing, handling and installation problems.
Appearance, construction ease and economics are typically the strong considerations in conventional construction of the curtain wall variety. For this reason it would be beneficial to provide a flexible joint structure which does not produce the deleterious bending forces of conventional designs and can facilitate water drainage. The method and apparatus of the present invention provides such an improvement over the prior art through a dynamic eave construction. The assembly utilizes a flexible joint across which a gap is provided preventing the abutting engagement of the inside surfaces of the angulated structural members during loading. Drainage ears on the upper rafter empty water behind the sealant and into the vertical mullion. In one embodiment a pivot pin is included within the joint for transmitting the structural load directly from the roof member to the vertical mullion and facilitating the pivotal interaction therebetween in a manner not detrimental to the structural integrity of the joint. Moreover, the flexible joint can be provided in an aesthetically pleasing configuration without the appearance of gusset plates, welds and the like.
SUMMARY OF THE INVENTION
The present invention pertains to a dynamic eave assembly and method of manufacture of the type facilitating a flexible structural interengagement between angulated building members. More particularly, one aspect of the invention comprises a flexible structural joint comprising first and second mullions adapted for generally angulated positioning relative one to the other. The first and second mullions intersect one another in an angulated relationship across a notional plane defined therebetween. Means are provided for coupling the first and second mullions one to the other in a pivotal relationship. Means are also provided for defining and maintaining a space along the notional plane of intersection between the first and second mullions to facilitate relative movement therebetween and flexibility of the mullions one to the other. The means coupling the first and second mullions comprise a pivot pin secured to one of the mullions and means associated with the other mullion for engaging the pin and affording pivotal movement.
In another aspect, the invention includes the structural joint as set forth above wherein the first mullion further includes a pivot arm secured therein having a journal formed therethrough and adapted for receipt of the pin therein. The second mullion includes a knee splice secured therein, the knee splice has apertures formed through the side walls thereof adapted for receiving the pin therethrough for facilitating pivotal motion about the journal. The knee splice can comprise a hollow channel having oppositely disposed apertures formed therethrough in axial alignment with the journal therein and means for securing the knee splice to the second mullion. The knee splice is further constructed with an angular end face adapted for receipt in and positioned adjacent the inside of the first hollow mullion. The means coupling the first and second mullions further includes first and second apertures formed in the the second mullion. The knee splice has first and second apertures formed therein adapted for registration with the apertures of the vertical mullion for the receipt of the pin therethrough and the pivotal action of the mullions therearound.
In another aspect, the invention includes the structural joint as set forth above wherein the second mullion is constructed with at least one drainage channel formed outwardly therealong. The drainage channel terminates along the notional plane of intersection between the first and second mullions and is adapted for discharging water therefrom into the first mullion. The structural joint further includes means disposed in a lower region of the first mullion adapted for sealably retaining water received from the second mullion and means disposed adjacent the sealing means for discharging the water received therein.
In another aspect, the invention includes an improved structural joint for the mitered intersection between vertical structural members and rafters coupled thereto of the type wherein the rafter is secured to the vertical member across an angulated intersection defining a notional plane of intersection therebetween. The improvement comprises means securing the rafter to the vertical member permitting pivotal movement therebetween. Means are provided for maintaining a spaced relationship across the notional plane of intersection between the vertical member and the rafter for allowing flexibility and relative movement therebetween. The spacer means of the structural joint comprises a pivot pin extending through one of the members and journal means secured to the other of the members adapted for receiving the pin therein and facilitating the the movement therearound. In this manner, loading of the rafter imparts a deflection thereto which is accommodated by movement about the pin. In one embodiment, the vertical structural member and rafter each comprise a hollow mullion adapted for intersecting one another in angulated relationship across the notional plane defined therebetween and the securement of glass panes thereto.
In yet another embodiment, a dynamic eave assembly is provided for coupling structural members in an angulated relationship one to the other and allowing flexibility therebetween for dynamic and static loading thereupon. The structure comprising means associated with the angulated members facilitating pivotal interaction therebetween and means for establishing a notional plane of intersection between the angulated members and a predefined space therebetween. The space accommodates the pivotal action during dynamic loading of the eave. The assembly further includes an elastomeric member disposed along the notional plane of intersection between the angulated members for filling the predefined space therebetween and accommodating relative movement therealong.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and for further objects and advantages thereof, reference may now be had to the following description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a side-elevational, cross-sectional view of the flexible joint of the present invention illustrating the interengagement of angulated structural members in accordance with the principles of the present invention;
FIG. 2 is a top plan, cross-sectional view of the assembly of FIG. 1 taken along lines 2--2 thereof and illustrating one embodiment of the pivot assembly of the present invention;
FIG. 3 is a side-elevational, cross-sectional view of an alternative embodiment of the flexible joint of FIG. 1 illustrating an exposed pin design;
FIG. 4 is a fragmentary, perspective view of the flexible joint structural members of FIG. 1 illustrating the incorporation of drainage ears in a hollow mullion configuration of the type adapted for commercial building construction;
FIG. 5 is a side-elevational, cross-sectional view of one embodiment of a lower region of the mullion of FIG. 1 illustrating the system of the present invention facilitating drainage of water collected within the hollow mullion;
FIG. 6 is an enlarged, fragmentary, cross-sectional view of the vertical wall section taken along line 6--6 of FIG. 5; and
FIG. 7 is an enlarged, fragmentary, perspective view of an alternative angle of the flexible joint structure member of FIG. 4 illustrating more clearly the drainage ears thereof.
DETAILED DESCRIPTION
Referring first to FIG. 1 there is shown a side-elevational, cross-sectional view of one embodiment of a dynamic eave, or flexible joint 10 constructed in accordance with the principles of the present invention. The flexible joint 10 is comprised of a generally vertical hollow mullion 12 and upper angulated mullion in the form of rafter 14 meeting one another across a notional plane of intersection 16. The members 12 and 14 are pivotally coupled one to the other in structural interengagement by a pin 18. The pin 18 is secured to lower member 12 through pivot arm 20 and to upper member 14 through knee splice, or pivot channel 22. The knee splice 22 is constructed with a curved nose 23 adjacent the pin 18 to eliminate engagement with the vertical member 12. This further facilitates use of a single size of channel 22 for a variety of interaction.
Still referring to FIG. 1, the lower pivot arm 20 is secure to the lower mullion 12 by attachment to the outer wall 24 with a plurality of threaded fasteners 26. The upper knee splice 22 is secured to outer wall 28 of rafter 14 by threaded fasteners extending therethrough. It should be noted that any conventional fastener would be appropriate. In this manner, a predefined gap, or space 32 is presented along the notional plane of intersection 16. Relative movement between rafter 14 and vertical mullion 12 is thus accommodated without the stresses normally associated therewith including the degeneration of structural integrity of the joint itself.
Referring still to FIG. 1, it may be seen that the gap 32 along the notional plane of intersection 16 separates the upper inside edge 34 of lower member 12 from the lower inside edge 36 of upper member 14. In this manner, loading of rafter 14 by dead loads, wind load, or the like which normally cause downward deflection in the direction of arrow 33 will not result in immediate engagement of edges 34 and 36 and the resultant stress amplification across the joint which leads to structural deterioration. In conventional eave construction, load deflection of rafter 14 will result in direct abutment of the inside mitered edges of the structural members. The abutting edges will resist the load and therein manifest a degree of compression and the resulting amplification of separation forces along the notional plane of intersection 16. The forces of separation which are outside point 38 are, in fact, amplified by the length of the notional plane of intersection in conventional assemblies. For this reason, gusset plates and similar reinforcing provisions are generally considered.
In the present invention, gap 32 generated by the securement of knee splice 22 and pivot arm 20 with pin 18 eliminates this serious problem of stress amplification. The pivot arm 20 is constructed with an upper pivot arm journal 40 having an aperture 42 formed therethrough, and structurally connected to the hollow mullion 12 by neck region 44 and depending body section 46. The upper knee splice 22 of the present embodiment is comprised of a metal channel section 48 having an angular end face 50, which is particularly cut for the predefined mitered angle of notional intersection between upper and lower members 14 and 12. Although other structural configurations may be provided for the pivotal interaction between roof and wall members, the assembly of FIG. 1 is particularly adapted for hollow mullions of the type typically used for commercial building construction.
Commercial structures are generally designed for maximum ease in assembly and minimum maintenance. For this reason, a myriad of "curtain wall" designs have been developed throughout the prior art whereby sheets of glass are secured to and sealed in hollow mullions generally constructed with extruded aluminum. The present invention is particularly adapted for the utilization of hollow mullion construction and the problems associated with angular roof members adapted for structural engagement with vertical members. As set forth above, such eave designs are conventional in residential construction utilizing wood which is not as susceptible to the stress amplification leading to structural failure through a mitered intersection. The fibrous nature of wood is readily compressible compared to metal. For this reason the engagement of inside mitered edges of rafters and studs will not create the same degree of load amplification or structural degeneration through the pivotal interaction typified in aluminum construction. Degeneration of a mitered joint can cause lack of structural integrity in the framework of a building system. Sealing failure may also occur, said failure being manifested by water intrusion from rain, snow and the like.
As deleterious as rainwater intrusion is, it is not nearly as catastrophic as a structural or load failure. Recent interest in commercial building designs utilizing a myriad of angular wall sections lending aesthetic beauty to the exterior of the building has lead to concern over the eave design. The very size of commercial buildings itself provides a plurality of structural considerations. These considerations are not generally addressed in residential structures with angular roof sections made of "softer" wood. The rigidity of the metal surfaces of the hollow mullions in mitered joints must however, be addressed because more conventional building designs have emphasized the elimination of the unpleasant appearance of gusset plates. A smooth joint is one design criteria and one which is the genesis of numerous problems. The perfectly mitered intersection of structurally rigid members must meet unconventional stress and strength of material considerations. As stated above, the vertical "dead" load is not the maximum stress to be found across the notional intersection plane 16. The effective creation of a fulcrum, or pivot point, between inside edges of a mitered joint create a leveraging and amplification of loads. Since relative movement and preselected degrees of elasticity are integral elements of architectural designs in commercial structures, the utilization of a dynamic eave such as the flexible pin joint 10 of FIG. 1 is inherently compatible with optimal design goals for structural integrity. The "dynamic" aspect of the eave as used herein refers to the relative movement allowed between members 12 and 14 as compared to the "static" framework of the conventional "mitered joint".
Referring now to FIG. 2, there is shown a top plan, cross-sectional view of the rafter 14 and the glass pane assembly 55 mounted therein. The glass pane assembly 55 is comprised of an outer glass sheet 56 and inner glass sheet 57, which forms a dead air space 58 therebetween. The dead air space is sealed at opposite ends by a spacer 60. The pane 55 is secured to the rafter 14 by an outer rafter cap 62, which engages the outer glass panes 56 through glazing rod members 64. The ends of the rafter caps 62 are also mitered for abutting aesthetic engagement. Members 64 provide weather tight seals against the glass surfaces, and are secured thereagainst by internal pin assembly 65. Pin assembly 65 is secured to the rafter cap 62 and to the internal mullion structure, as defined below. Because of the manner of installation, no "leveraged" stresses are imposed thereby. Appropriate sealant 67 is likewise injected into the mullion for preventing water intrusion, as is convention in curtain wall designs.
Still referring to FIG. 2, there is shown the structural assembly of the flexible joint 10 of FIG. 1 from a top plan view. The rafter 14 is shown to be constructed in this particular embodiment with a pair of internal flanges 70 and 71 adapted for receipt of knee splice 22. The knee splice 22 is a generally U-shaped member adapted for securement to rafter 14 by fasteners 30 as set forth in FIG. 1. Pivot arm journal 40 is shown therebeneath in receipt of pivot pin 18, therethrough. Pin 18 extends through the central aperture 42 of pivot arm journal 40 and into apertures 75 forming the side walls of the knee splice 22. In this manner, the knee splice 22 secures the rafter 14 while allowing pivotal action across the pin 18 through the pivot arm 20. The pin may be a 1/2" diameter rod, or the like, with the knee splice formed of aluminum.
Referring still to FIG. 2, there is shown one embodiment of the cross-sectional construction of the rafter 14. As set forth above water intrusion is a major design aspect and in even more critical with angulated roof sections. The rafter 14 is thus constructed for affording improved water collection and drainage capacity. A pair of upper gasket elements 80 are provided for engaging inside gaskets 82 bearing against inside glass panes 57. The lower end 83 of rafter 14 is formed with a pair of oppositely disposed drainage ears, or channels 84 and 85, each having an upstanding outer flange 86. The drainage channels 84 and 85 are provided for collecting and vectoring any condensed or intruded water along the rafter 14 into the adjoining vertical wall mullion 12. In describing the channeling of said water, attention is directed back to FIG. 1, where flange 86 of channel 85 may be seen. The channels 84 and 85 each include an inside angulated wall portion 90 of rafter 14, which is most clearly seen in FIG. 1. The angulated wall portion 90 provides the indentation region for the formation of said channels. The lower end 92 of the channel 85 is shown to terminate at the notional plane of intersection 16 and in the upper region of the vertical mullion 12. Water collected in channels 84 and 85 is then vectored therein, and carried downwardly and away as described in more detail below.
Referring back to FIG. 1, the assembly therein further illustrates the position of glass assembly 55 which includes glass panes 56, 57 and dead air space 58 therebetween. The rafter cap 62 and a vertical mullion cap 63 are shown to comprise the outer most surfaces of the assembly 10 with the underlying glazing rod 64 depicted thereon in engagement with the outer glass sheet 56. Spacers 60 are likewise shown at the intersecting regions of the glass panes of the vertical wall mullion 12 and angulated rafter 14. An eave cap 97, preferably formed of extruded aluminum is shown formed therein in a configuration adapted for an angular intersection of the respective hollow mullion members 12 and 14. A suitable caulking and sealing compound 98 is provided therearound with expandable gasket member 99 secured therein. Although the sealing members generally prevent outside water intrusion, some water because of human error will infiltrate at the rafter 14 to be collected in the channels 84 and 85, as discussed above. Water draining through the channels is ultimately deposited into the hollow region of the vertical mullion 12, as shown along the intersection line 92. The elastomeric sealant 32 provided between the spaced members 12 and 14 is left open along the end of the channels 84 and 85 to permit the passage of water and effective drainage therethrough. As described in more detail below, the water draining into the hollow mullion 12 is collected in a lower region and eliminated through a complemental drainage system.
Referring now to FIG. 3, there is shown an alternative embodiment of the dynamic eave assembly 10 of the present invention. The flexible pin joint is herein constructed with an exposed pin 18, but without the pivot arm 20 as shown in FIG. 1. The assembly 10 doss comprise rafter cap 62 secured against the glass assembly 55 by glazing rod 64. The vertical mullion 12 is likewise constructed for notional angular intersection. Upper rafter 14 thus includes drainage channel 85 formed therein by angulated wall section 90 and upstanding flange 86. The notional line of intersection 16 is shown to be filled with an elastomeric sealant 32 such as silicone or the like. Pin 18 is shown to extend through knee splice 22 in a manner similar to that shown in FIG. 1. The distal end 50 body section 48 is formed in an angulated relationship providing a space 101 between the end 50 and the frontal wall of the vertical mullion 12. An aperture 103 is formed in the vertical mullion 12 in position for receiving pin 18 therethrough and permitting the pivoting of the knee splice 22. In this manner, static and dynamic loading upon the rafter 14 which causes deflection in the direction of arrow 105 will produce some degree of pivoting (as indicated by arrow 107) about the pin 18. Pivotal movement 107 will result in some degree of closing at the inside joint region 109 (as indicated by arrow 108). With a sufficient gap provided along the notional plane of intersection 16, the movement 108 will not cause contact between the respective inside surfaces of the vertical mullion 12 and rafter 14 at point 109. A suitable gap is thus necessary for this dynamic eave configuration. Likewise, a suitable elasti material spacer 32 positioned in the notional plane of intersection 16 will allow the movement indicated by arrows 105, 107 and 108 without imparting stresses to the structural members 12 and 14. This can also be provided without interfering with the water passing through drainage channel 85. As discussed in more detail below, this drainage permits water to be eliminated from the rafter 14 into the wall region of the mullion 12 for elimination therebeneath.
Referring now to FIG. 4, there is shown a fragmentary perspective view from a first angle of one embodiment of the structural members of the dynamic eave assembly 10 of the present invention. A section of upper rafter 14 is shown mitered and assembled to a mitered section of lower vertical mullion 12 with glazing rods, glass panes, clips, and eave caps removed for purposes of illustration. The notional plane of intersection 16 is shown with the sealant member 32 disposed therebetween. Drainage trough 85 is shown channeled therethrough. Flange member 86 is disposed outwardly of tapered wall 90 along rafter 14 to facilitate water collection into vertical mullion 12. Central fins 135 upstand from the frontal region of the rafter 14 and vertical mullion 12 to form an upstanding channel 137 therebetween. Channel 137 is adapted for receiving the clip 65 as shown in FIG. 2. Rafter cap 62 may then be secured thereto. The threaded fasteners 30 are also shown therein in engagement with an underlying knee splice 22, (not shown) in accordance with one embodiment of the present invention.
Referring now to FIG. 5 there is shown a side-elevational, cross-sectional view of one embodiment of a lower region of the vertical mullion 12 providing for water elimination. A water deflector plate 120 is thus angularly disposed therein. The assembly shown in FIG. 5 is comprised of a sill member 110 having a glazing rod engagement tine 112 extending outwardly therefrom in engagement with glazing rod 64. A sill fin 114 is likewise provided for coupling to elongate clip 65 adapted for engaging fin 115 formed in the outside wall 116 of the lower outside sill structure. Sealant 118, is provided outwardly and inwardly of the sill for conventional sealing. The water deflection member 120 provided inside the hollow mullion 12 then comprises an angular bulkhead. The bulkhead 120 includes an upstanding inside wall engagement member 122 and a depending outside wall engagement member 124. A securement block 125 is formed therein and adapted for receiving threaded fastener member 126 therethrough. In this manner, the water deflector 120 is secured within the mullion 12, providing an enormous storage volume thereabove for water intrusion occurring from leaks, condensate and the like. A suitable sealing compound 128, such as silicone or the like, is utilized in conjunction with the bulkhead 120 for affecting complete sealing therearound. A drainage aperture 130 is provided adjacent to the lower region of said deflection member for passing water outwardly. Water is therein caught above glazing rod 64 between the walls of the hollow mullion 12 and the glass assembly 55 and conventional drainage channels (not shown) are provided for drainage outwardly therefrom.
Referring first to FIG. 6 there is shown an enlarged, top-plan, cross-sectional, fragmentary view of the vertical mullion 12 of FIG. 5 illustrating the drainage aperture 130 formed therethrough. Fins 135 of channel 137 are seen to upstand from adjacent sides of the aperture 130. It is important to note that the aperture 130 is positioned within the channel 137, whereby water egressing therefrom is allowed to migrate outwardly from the vertical mullion 12. For purposes of orientation gasket elements 80 are shown, said elements 80 being as adapted for engaging inside gaskets 82 (not shown). The drawing of FIG. 6 is, moreover, to be viewed in conjunction with the view of the aperture 130 of FIG. 5 in order to illustrate the manner in which drainage is provided from the drainage bulkhead 120 in accordance with one aspect of the present invention.
Referring now to FIG. 7, there is shown an enlarged perspective, fragmentary view of the flexible knee joint of the present invention in an alternative orientation to that shown in FIG. 4. The view of FIG. 7 more clearly illustrates the mitered intersection between the upper rafter 14 and vertical wall member 12 and the notional plane of intersection 16 therebetween. The particular structural elements 12 and 14 of this embodiment comprise the hollow mullions described above, which mullions very efficiently facilitate the water drainage aspect of the present invention. The intersection plane 16 further defines an open flow area 150 formed by the tapered wall section 90 of the rafter 14 adjacent the planar wall section of the vertical member 12. The open area 150 is in mating communication with the drainage channels 84 and 85 whereby water collected therein is vectored directly into the hollow region of the vertical mullion 12. Upper gasket elements 80 and the inside configuration of fins 135 are also shown in this view. This configuration should be viewed in conjunction with the fin construction shown in FIG. 2 adapted for engaging the internal pin assembly 65. Inside structural flanges 153 and 154 are likewise shown projecting inwardly within the hollow mullion region of rafter 14, which configuration comprises but one embodiment of a construction of the hollow mullion 14.
The present invention teaches a dynamic eave assembly comprising a flexible joint configuration. It should be noted that the invention is not limited to hollow mullion configurations. I-beam structures and the like may be utilized. Such assemblies could include side wall members which engage the oppositely disposed top and bottom sections of the I-beam in generally parallel spaced relationship relative to the central web portion of the I-beam. This particular configuration is not shown due to the fact that I-beam construction is conventional in the prior art and the teachings of the present invention are enabling for such a dynamic eave. Likewise, solid structure members including wooden beams can likewise be adapted with flexible joint members as herein defined for facilitating the dynamic eave configuration and the myriad of advantages thereof. The utilization of the hollow mullion in the drawings of FIGS. 1-7 are, however, helpful in illustrating one method of coupling a pivotal member such as knee splice 22. Likewise the hollow mullion configuration facilitates various drainage aspects and the formation of the drainage channels 84 and 85. It should be seen that the utilization of various glass sealing and glazing elements, eave and rafter caps, securement assemblies (such as pin assembly 65), and related structural elements currently utilized in contemporary curtain wall design may be modified in various ways to accommodate the structure of the present invention. When using the hollow mullion configuration set forth above, the incorporation of the knee splice 22, having the curved nose portion 23 described above, greatly facilitates the use of a single knee splice assembly for a variety of angles of structural joint intersections. The rafter 14 and vertical member 12 can therein be constructed for a variety of angular relationships which are accommodated by a single structural design of the knee splice 22 and lower pivot arm 20. In essence, angular variations are accommodated by altering the hole pattern of fasteners 26 and 30 to shift the position of the pivot arm journal 40 and knee splice 22.
As set forth above, the dynamic eave 10 of the present invention affords structural interengagement facilitating static and dynamic loading without the inherent stresses and structural degeneration conventional in hollow mullion eave assemblies. The present invention provides structural integriy and water elimination without utilization of exposed welds, gusset plates, rivets and the like. The dynamic eave 10 may be constructed with an exposed pin 18 as shown in FIG. 3 or with the hidden pin 18 shown in FIGS. 1 and 2. It should also be noted that the pin configuration is but one structural embodiment and a plurality of other pivotal approaches may be utilized. The present invention also lends itself to improved drainage and during periods of high wind or rain, water intrusion problems can be substantially eliminated along with the associated "loading" problems from a structural standpoint. It may further be seen that various angular intersections can be provided between the vertical mullion 12 and rafter 14. These angular differences are accommodated by variations in the knee splice 22 and the assembled in conjunction therewith.
It is thus believed that the operation and construction of the present invention will be apparent from the foregoing description. While the method and apparatus shown and described has been characterized as being preferred, it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the following claims. | A dynamic eave building system comprising a flexible joint for first vertical and second angulated structural members pivotally connected one to the other. The adjacent ends of the first and second structural members are mitered into a mating configuration and spaced one from the other by the pivot joint. The pivot joint comprises a pivot pin received through aligned apertures formed in one of the members and in a knee splice secured in the other. The knee splice is positioned to define the flexing space between the mitered ends. The second angulated member also includes moisture collection troughs formed longitudinally therealong. The first member is provided in a hollow configuration for receiving fluid flow from the troughs of the second angulated member. Both members are adapted for securement of conventional curtain wall material, siding or roofing thereon. In this manner, loads on the second angulated member is transferred directly to the first vertical member through the pivot joint and any flexing therein is accommodated by the space between mitered edges. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a simplified mechanism for rotating a mounting having one, or multiple, decorative items, including a gemstone, secured therein.
2. Description of the Prior Art
U.S. Pat. No. 7,536,874 to Ray et al discloses a jewelry item with a substantially hollow housing having a bezel and gemstone rotatably mounted on the upper end thereof. Received within the housing is a motor that operates a plurality of interrelated, contiguous gears to rotate the bezel. The gear ratios are such that the bezel will rotate at a predetermined, selected speed to achieve a desired aesthetic affect. A switch having a battery mounted thereon is hingedly attached to a side edge of the housing for activating the motor.
Although the Ray et al provides a device for rotating a gemstone in order to provide a pleasing aesthetic effect, the device is complex and requires a significant number of components, including three gears and a motor.
What is desired is to provide a jewelry item having at least one decorative item, including a gemstone, secured in a mounting that has a relative simple mechanism for manually rotating the mounting.
SUMMARY OF THE INVENTION
The present invention provides a jewelry item having a gemstone that is manually rotatable to provide a discrete aesthetic appearance.
The device for rotating the decorative item comprises a hollow, cylindrical frame member having an exterior surface, a circular, multi-tooth gear ring mounted to the exterior surface of the frame member, a stem, or crown, having a gear mounted on its shaft which is positioned to engage the teeth on the circular gear, a rotatable mount having a shaft extending there through, one end of the shaft supporting the mount, the other shaft end coupled to a drive gear which, in turn, is positioned to engage the teeth on the circular gear.
The decorative item is rotated by the user turning the crown, in either a clockwise or counterclockwise direction, the gear mounted thereto rotating in a manner such that the gear teeth thereon engage the gear teeth on the circular gear causing the circular gear to rotate. Since the teeth on the circular gear already in engagement with the teeth on the bezel gear, the mount is used to rotate which, in turn, enabling the decorative items coupled to the mount also to rotate.
The present invention thus provides a relatively simple and inexpensive mechanism for rotating decorative items positioned on a jewelry item.
DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention as well as other objects and further features thereof, reference is made to the following description which is to be read in conjunction with the accompanying drawing therein:
FIG. 1 is a perspective view illustrating the ring rotating mechanism of the present invention;
FIG. 2 is a plan view of the mechanism shown in FIG. 1 ; and
FIG. 3 is an exploded view of the ring rotating mechanism of the present invention.
DESCRIPTION OF THE INVENTION
Referring to FIGS. 1-3 , jewelry item 10 , such as a ring, comprises a multi-toothed gear 12 , circular multi-toothed gear 14 and multi-toothed gear 16 and crown, or stem 18 . Crown 18 is arranged so that it is rotatable about pin 20 having recesses 43 . The teeth of gear 12 engages the teeth of gear 14 which in turn is positioned to engage the teeth of gear 16 . Gear 16 is rotatably mounted onto shaft 22 , a setting 24 having multiple prongs 26 formed thereon. A gemstone 28 is secured to jewelry item 10 by prongs 26 in a manner well known in the jewelry industry. A ring member 30 is secured to the internal surface 32 of gear 14 which enables the ring wearer to insert a finger there through.
As shown in FIG. 3 , a plurality of protrusions 34 extend from the bottom surface of plate 36 and are adapted to engage corresponding recesses 40 formed on the upper surface of gear 16 . Protrusions 34 and recesses 40 have male and female teeth which, when engaged, lock together. Bezel gear 16 extends through the gemstone head holder, the external surface of band 30 supporting a circular wire 9 that extends along circumference of band 30 and is soldered thereto. Band 30 engages circular multi-toothed gear 14 , inner surface 32 having a female groove for receiving wire 9 , wire 9 extending through gear 14 thus locking gear 14 to internal surface of band 30 . Note that the wire 9 shown to the right of ring member 30 is not to scale but, in actuality, is sized to extend complete around the external surface of ring member 30 .
The internal surface of band 30 has two holes 41 and 42 for receiving pin 13 therethrough.
As illustrated, a single gear 16 is disposed at the top of ring member 30 and single gear 12 is disposed at the bottom of ring member 30 .
Crown 18 (top view shown below shaft 20 , a bottom view of crown 18 is shown by reference numeral 18 ′ engages shaft 20 and pin 13 passes through each; crown 18 , shaft 20 and pin 13 engage the internal surface of ring 30 and are soldered thereto.
Bezel 11 is positioned within opening 46 of crown 18 and is soldered to shaft 20 and crown 18 to keep the assembly together.
In order to enhance the aesthetic effect resulting from the reflection and sparkling of a stationary gemstone, the ring wearer has the option of rotating crown 18 . Specifically, when the ring wearer elects to rotate crown 18 , gear 14 is, as a result, rotated. The rotation of gear 16 then rotates shaft 22 which causes gemstone 28 to be rotated, providing the effect noted hereinabove. Thus, rotation of crown 18 causes the essentially simultaneous rotation of gear 14 , gear 16 , shaft 22 and gemstone 28 .
Although not shown, the mounting plate 36 can be designed such that additional settings for receiving additional gemstones are formed thereon. In addition, at least one guard member (not shown) can be positioned to surround gear 14 to enhance the appearance of ring 10 .
While the invention has been described with reference to its preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the true spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its essential teachings. | A mechanism for manually rotating decorative items, such as a gemstone, on an item of jewelry. The mechanism includes a circular ring gear that engages gears formed on a manually rotated crown member and on the mounting securing for the decorative items. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/995,534, filed Sep. 27, 2007, and U.S. Provisional Application No. 60/999,310, filed Oct. 17, 2007, the entire contents of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The present disclosure relates generally to orthopedic spine surgery and in particular to devices, systems, and methods for vertebral body spacing using a posterior or transformational surgical approach.
DESCRIPTION OF THE RELATED ART
[0003] The human spine is comprised of thirty-three vertebrae at birth and twenty-four as a mature adult. The vertebra is made up of the vertebral body and posterior elements, including the spinous process, transverse processes, facet joints, laminae, and pedicles. The vertebral body consists of a cortical shell which surrounds the cancellous center. Between each pair of vertebrae is an intervertebral disc, which maintains the space between adjacent vertebrae and acts as a cushion under compressive, bending and rotational loads and motions. A healthy intervertebral disc has a great deal of water in the nucleus pulposus; the center portion of the disc. The water content gives the nucleus a spongy quality and allows it to absorb spinal stress. Excessive pressure or injuries to the disc can cause injury to the annulus; the outer ring that holds the disc together.
[0004] Generally, the annulus is the first portion of the disc that seems to be injured. These injuries are typically in the form of small tears. These tears heal by scar tissue. The scar tissue is not as strong as normal annulus tissue. Over time, as more scar tissue forms, the annulus becomes weaker. Eventually this can lead to damage of the nucleus pulposus. The nucleus begins to lose its water content due to the damage; it begins to dry up. Because of water loss, the discs lose some of their ability to act as a cushion. This can lead to even more stress on the annulus and still more tears as the cycle repeats. As the nucleus loses its water content it collapses, allowing the vertebrae above and below the disc space to move closer to one another. This results in a narrowing of the disc space between the two vertebrae and often times impingement of the nerves branching off the spinal cord. As this shift occurs, the facet joints located at the back of the spine are forced to shift. This shift changes the load distribution and balance at the facet joints affecting the way the facet joints work together and can lead to problems in the facet joints or to a premature breakdown of the joint.
[0005] When a disc or vertebrae is damaged due to disease or injury standard practice is to remove part or all of the intervertebral disc, insert a natural or artificial disc spacer and construct an artificial structure to hold the affected vertebrae in place to achieve a spinal fusion. In doing so, while the diseased or injured anatomy is addressed and the accompanying pain is significantly reduced, the natural biomechanics of the spine are affected in a unique and unpredictable way and, more often than not, the patient will develop complicating spinal issues in the future.
[0006] To that end, it would be advantageous to treat the disease or injury while maintaining or preserving the natural spine biomechanics. Normal spine anatomy, specifically intervertebral disc anatomy, allows one vertebrae to rotate, with respect to its adjacent vertebrae, about all three axes of the spine. Similarly, the intervertebral disc also allows adjacent vertebrae to translate along all three axes, with respect to one another.
[0007] For the above stated reasons, an implantable device which may be used to maintain the disc space between adjacent vertebrae, allow rotation about at least one axis and allow translation about at least one axis, and have a means to prevent expulsion while complementing a posterior stabilizing spinal construct would be helpful. The implantable device would be capable of being introduced into the body using a posterior approach, similar to a PLIF, T-PLIF, or X-PLIF spinal fusion device and may provide a prolonged life span in the body that can withstand early implantation, as is often indicated for younger patients, and will have a limited amount of particulate debris so as to reduce complications over the useful life of the device.
SUMMARY
[0008] An implantable device includes a spacing member and an elongate member. The elongate member includes a body portion having a first end coupled to the spacing member and a second end having a retention member. The spacing member is compressible and may be configured to include dual directional radii along a longitudinal axis and a lateral axis. In embodiments, the spacing member is oblong. The spacing member is configured to translate along at least one axis and rotate about at least one axis.
[0009] In a system for maintaining disc space between adjacent vertebrae, the implantable device is used in conjunction with a spine fixation member. The spacing member of the implantable device is adapted for insertion into a disc space between a pair of vertebrae and a spine fixation member is disposed between the pair of vertebrae. In embodiments, the spine fixation member includes bone anchors adapted to be affixed to the vertebrae and a spinal rod which is placed across and secured to the bone anchors. The elongate member of the implantable device is affixed to the spacing member on a first end which is configured to extend out of the disc space. A second end of the elongate member is adapted to be releasably connectable with the spine fixation member in order to prevent expulsion of the spacing member from the disc space.
[0010] Methods of using the system, including unilaterally and bilaterally replacing diseased or damaged intervertebral discs from a posterior or transformational approach, are also disclosed. In accordance with the present disclosure, bone anchors are placed in adjacent vertebrae of a patient. A spacing member operably connected to an elongate member is introduced into a disc space opening formed between the adjacent vertebrae. A spinal rod is placed across and secured to the bone anchors and the elongate member is secured thereto. In embodiments utilizing a unilateral vertebral body spacing device, a single spacing member is placed centrally between the adjacent vertebrae. In embodiments utilizing a bilateral vertebral body spacing device, two spacing members are bilaterally placed between the adjacent vertebrae.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The foregoing and other features of the present disclosure will become apparent to one skilled in the art to which the present disclosure relates upon consideration of the following description with reference to the accompanying drawings, wherein:
[0012] FIG. 1A is a top view of a single level construct with the vertebral body spacing device, placed bilaterally, in accordance with the present disclosure;
[0013] FIG. 1B is an end view of the single level construct with the vertebral body spacing device of FIG. 1A ;
[0014] FIG. 1C is a side view of the single level construct with the vertebral body spacing device of FIG. 1A ;
[0015] FIG. 2A is a top view of the vertebral body spacing device of FIGS. 1A-1B ;
[0016] FIG. 2B is an isometric view of the vertebral body spacing device of FIGS. 1A-1B ;
[0017] FIG. 2C is a cross-sectional view of the vertebral body spacing device of FIGS. 1A-1B ;
[0018] FIG. 2D is a side view of the vertebral body spacing device of FIGS. 1A-1B ;
[0019] FIG. 3A is a top view of a single level construct with a vertebral body spacing device, placed centrally, in accordance with the present disclosure;
[0020] FIG. 3B is an end view of the single level construct with the vertebral body spacing device of FIG. 3A ;
[0021] FIG. 3C is a side view of the single level construct with the vertebral body spacing device of FIG. 3A ;
[0022] FIG. 4A is a top view of the vertebral body spacing device of FIGS. 3A-3B ;
[0023] FIG. 4B is an isometric view of the vertebral body spacing device of FIGS. 3A-3B ;
[0024] FIG. 4C is a side view of the vertebral body spacing device of FIGS. 3A-3B ;
[0025] FIG. 4D is a cross-sectional side view of the vertebral body spacing device of FIGS. 3A-3B ;
[0026] FIG. 5A is a top view of an alternate embodiment of the spacing member of the vertebral body spacing device in accordance with the present disclosure;
[0027] FIG. 5B is a front view of the spacing member of FIG. 5A ;
[0028] FIG. 5C is a cross-sectional view of the spacing member of FIG. 5B taken along line C-C;
[0029] FIG. 6A is a front view of another embodiment of the spacing member of the vertebral body spacing device in accordance with the present disclosure;
[0030] FIG. 6B is a front view of the spacing member of FIG. 6A ; and
[0031] FIG. 6C is a cross-sectional view of the spacing member of FIG. 6B taken along line B-B.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0032] The vertebral body spacing device of the present disclosure is used in orthopedic spine surgery. A spacing member for maintaining disc space between adjacent vertebrae is coupled with an elongated member which is used to prevent the device from expelling out of the disc space. The device is contemplated as a single, central vertebral body spacing device attached to one spinal rod or as a bilateral device attached to bilaterally placed spinal rods. Either orientation will facilitate a fusion or dynamic stabilization procedure. The former takes advantage of Wolff's Law when a bone graft is introduced. The latter may be used with a posterior dynamic rod system providing anterior column support thereby helping to unload the facet joints and restore balance to the spine.
[0033] Referring now to the drawings, in which like reference numerals identify identical or substantially similar parts throughout the several views, FIGS. 1A-2D illustrate views of an embodiment of the vertebral body spacing device, placed laterally, in accordance with the principles of the present disclosure. Vertebral body spacing device 10 includes spacing member 20 and elongate member 30 .
[0034] Spacing member 20 is dimensioned to be positioned between two adjacent vertebrae. Spacing member 20 has sufficient contact surface area with a vertebral body endplate such that minimal subsidence into the endplate occurs and rotation about the longitudinal axis of the spine is possible. As illustrated in the current embodiment, spacing member 20 defines a longitudinal axis “A” and a lateral axis “B” ( FIGS. 2B and 2D ). Spacing member 20 is elongated along longitudinal axis “A” in the shape of an oblong. The oblong shape provides dual directional radii, one in the longitudinal axis “A” and the other in the lateral axis “B”, along the outer surface of spacing member 20 . The dual directional radii of the oblong outer surface of spacing member 20 provides an articulating surface whereby rotation of the vertebrae about the other two axes is achieved. Other shapes are within the purview of those skilled in the art for providing rotational movement to the vertebrae, such as other spherical shapes having two radii of curvature.
[0035] Spacing member 20 is also compressible. Material selection may also affect compressibility of spacing member 20 . Spacing member 20 may be made of biocompatible materials, including polymeric, metallic, and composites thereof. Polymeric materials include, for example, polyethylene, polypropylene, polyurethane, and polyetheretherketone. Metallic materials may include metals such as surgical grade stainless steel and titanium alloys. In the current embodiment, spacing member 20 may be a composite of a first material 21 within a second material 23 . In some embodiments, the first material 21 may provide a soft segment and the second material 23 may provide a hard segment.
[0036] The degree of translation, therefore, is affected by the material properties and the geometry of the spacing member 20 as well as by other means within the purview of those skilled in the art. For example, translation along the other two axes may be achieved by sizing spacing member 20 appropriately for the disc space such that the working area of spacing member 20 is within the softer, interior area of the endplate, as it is the cortical rim of the endplate which prevents further translation of one vertebral body to the other.
[0037] As illustrated in FIGS. 5A-6C spacing member 320 may include voids 322 to allow flexure of the implant in predefined directions. Voids 322 may be generally cylindrical shaped and extend at least partially through spacing member 320 . Voids 322 may be radially spaced about spacing member 320 and may be equally or unevenly spaced thereabout. Further, the voids may be any shape within the purview of those skilled in the art. The placement, number, and size of voids 322 within spacing member 320 may be controlled as needed to provide flexibility along at least one predefined axis.
[0038] Referring again to FIGS. 1A-2D , spacing member 20 includes opening 24 for coupling with elongate member 30 . Opening 24 extends at least partially into spacing member 20 and is configured and adapted to securely receive elongate member 30 .
[0039] Elongate member 30 is connected to spacing member 20 in order to prevent expulsion of spacing member 20 when positioned in a disc space. Elongate member 30 includes a body portion 32 having a first end 34 and a second end 36 . First end 34 of elongate member 30 is coupled with opening 24 of spacing member 20 . First end 34 is configured and adapted to fit within opening 24 of spacing member 20 . As illustrated in the current embodiment, first end 34 and opening 24 are press fit to couple elongate member 30 and spacing member 20 . First end 34 of elongate member 30 may be connected with opening 24 of spacing member 20 through any mechanical and chemical means within the purview of those skilled in the art, such as, for example, interference fitting, press fitting, friction fitting, welding, and adhesive binding.
[0040] Second end 36 of elongate member 30 includes retention member 38 for releasably coupling elongate member 30 , and thus spacing member 20 , to spine fixation member 40 . Spine fixation member 40 may be any posterior stabilizing longitudinal member within the purview of those skilled in the art, such a solid spinal rod 42 spanning at least two bone anchors 44 . Retention member 38 may be any member capable of securing elongate member 30 to spine fixation member 40 . As illustrated in the current embodiment, retention member 38 is a hook 39 a and screw 39 b set. Other comparable mechanical means for attached the elongate member 30 to spine fixation member 40 are envisioned and within the purview of those skilled in the art.
[0041] Elongate member 30 is a semi-rigid device capable of being bent in such a way as to allow implantation and alignment of the device using standard posterior or transforminal approaches and preventing interference with anatomy, such as the exiting nerve root, once implanted, while maintaining the formed shape.
[0042] A system 50 for maintaining disc space between adjacent vertebrae utilizes the vertebral body spacing device 10 of the present disclosure in conjunction with a spine fixation device 40 including pedicle screws 44 and rod 42 . Any spine fixation member 60 , however, adapted to span across adjacent vertebrae and capable of being coupled to vertebral body spacing device 10 may be utilized.
[0043] Pedicle screws 44 are bilaterally placed at adjacent vertebrae such that each set of pedicle screws 44 are aligned on one side of the vertebrae. The surgeon modifies the appropriate anatomy in order to access the disc space between the vertebrae for accepting spacing members 20 . Spacing members 20 are fitted to the disc space. Elongate members 30 , which may be fastened with its respective spacing member 20 via first end 34 prior to implantation or subsequently coupled to spacing member 20 after placement in the disc space, extends out of the disc space and is manipulated for optimal placement of the device. Elongate member 30 may be bent, twisted, curved, straightened, or otherwise shaped to ensure proper securement of spacing member 20 within the disc space, to prevent interference with the existing anatomy of the patient, and to properly align the retention member 38 of the elongate member 30 with spine fixation member 40 . Rods 42 are placed across and secured to its respective set of pedicle screws 44 and retention member 38 of the elongate member is secured thereto. In embodiments in which retention member 38 is a hook 39 a and screw 39 b set, the hook 39 a is positioned around rod 42 and screw 39 b is placed therethrough to fasten the hook 39 a to rod 42 . As illustrated the vertebral body spacing devices 10 are placed bilaterally within the vertebrae such that each spacing device 10 is on the same side as the spine fixation member 40 to which it will be fastened.
[0044] In some embodiments, before implantation of spacing member 20 , a trial device may be attached to a spinal rod and introduced into the disc space for appropriate sizing of the spacing member 20 and to determine if there will be any soft tissue interference by the introduction of the spacing member 20 into the disc space. The trial device may be used to ascertain the amount of contacting surface area of spacing member 20 with the vertebral body endplate to ensure rotational movement of spacing member 20 .
[0045] The vertebral body spacing device of the present disclosure is also contemplated to be used as a single, central vertebral body spacing device as illustrated in an alternate embodiment shown in FIGS. 3A-4D . Vertebral body spacing device, shown generally as 110 , includes spacing member 120 having opening 124 and elongate member 130 including body portion 132 having first end 134 and second end 136 . First end 134 is configured for coupling with opening 124 of spacing member 120 and the second end 136 includes retention member 138 which is adapted to be mechanically fastened to a spine fixation member 140 .
[0046] In this embodiment, spacing body 120 is elongated along lateral axis “B” to ensure a central fitting and sufficient contact of the working area of the spacing member 120 within the softer, interior area of the endplate between adjacent vertebrae. By providing more contacting surface area of spacing member 120 with the vertebral body endplate, a system 150 for maintaining disc space between adjacent vertebrae utilizing a unilateral vertebral body spacing device 110 may be achieved.
[0047] System 150 includes spine fixation device 140 including pedicle screws 144 and rod 142 similar to that described above in FIGS. 1A-2D .
[0048] Pedicle screws 144 may be bilaterally placed at adjacent vertebrae in order to provide proper bone fixation between the adjacent vertebrae. Alternatively, a single set of pedicle screws 144 may be placed at adjacent vertebrae. The surgeon modifies the appropriate anatomy in order to access the disc space between the vertebrae for accepting a single spacing member 120 . A trial device may be introduced into the disc space for appropriate sizing of spacing member 120 or the spacing member 120 may be directly fitted to the disc space. Elongate member 130 , which may be fastened with spacing member 120 via first end 134 prior to implantation or subsequently coupled to spacing member 120 after placement in the disc space, is manipulated for optimal placement of the device. Rods 142 are placed across and secured to its respective set of pedicle screws 44 . Retention member 138 of elongate member 130 may be affixed and secured to either rod 142 .
[0049] Vertebral body spacing device 10 may be fabricated as a single unit or multiple pieces designed for assembly by the surgeon at the time of use. Further, individual components of the vertebral body spacing device 10 , i.e. the spacing member 20 and elongate member 30 , may likewise be built as a single unit or include more than one piece for assembly. As a single unit, the device or component may be monolithically formed or pre-formed as a composite of multiple pieces. The vertebral body spacing device 10 and unassembled components thereof may be available in a range of sizes to better fit the patient's anatomy and offer greater surgical flexibility.
[0050] It will be understood that various modifications may be made to the embodiments disclosed herein. Therefore, the above description should not be construed as limiting, but merely as an exemplification of the embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the present disclosure. Such modifications and variations are intended to come within the scope of the following claims. | An implantable device includes a spacing member and an elongate member. The elongate member includes a body portion having a first end coupled to the spacing member and a second end having a retention member. In a system for maintaining disc space between adjacent vertebrae, the implantable device is used in conjunction with a spine fixation member. The spine fixation member includes bone anchors and a spinal rod for releasably securing the retention member of the elongate member thereto in order to prevent expulsion of the spacing member from the disc space. Methods of using the system include unilaterally and bilaterally replacing diseased or damaged intervertebral discs from a posterior or transformational approach. | 0 |
BACKGROUND OF THE INVENTION
The present invention generally relates to excavating apparatus and, in a preferred embodiment thereof, more particularly provides a uniquely configured excavating tooth point and adapter assembly representatively including a tooth point connected to an adapter section having interconnected main and intermediate portions.
Large excavating buckets, dippers and the like are typically provided with a series of earth-cutting tooth assemblies each comprising a relatively large adapter section and a relatively small replaceable tooth point. The adapter section has a base portion which is connectable to the forward lower lip of the bucket, and a tapered nose portion onto which the tooth point is removably secured, with the tapered adapter nose being received in an interior pocket portion of the point, by a suitable connecting pin or other connecting structure. Compared to that of the adapter section, the useful life of the point is rather short, the adapter section typically lasting through several point replacements until the tremendous earth forces and abrasion to which the adapter section is subjected necessitates its replacement. Thus, the point may be characterized as a wear member, and the adapter section may be characterized as a support structure carrying the wear member and protected thereby against premature replacement.
The adapter section may be a single adapter, or may be formed from a primary adapter which is connectable to the bucket lip, and an intermediate adapter which is interposed between the replaceable tooth point and the primary adapter and releasably connected to them. The intermediate adapter has a front nose portion which is captively and releasably retained within a complementarily configured rear end pocket area of the point by a first connector structure, and the main adapter has a front nose portion which is captively and releasably retained within a complementarily configured pocket area in the rear end of the intermediate adapter by a second connector structure. Thus, the replaceable tooth point functions as a wear member carried on and protecting the intermediate adapter, with the intermediate adapter functioning both as a support structure for the point and a wear member for the main adapter which supports the intermediate adapter.
Designing the configuration of an adapter nose, its interfit with its associated wear member (such as a point or another adapter), and its relationship with the connector structure used to releasably couple the adapter nose to the associated wear member, presents a variety of engineering challenges. For example, to maximize the earth penetration capabilities of a particular adapter/tooth point assembly the frontal cross-section of the assembly must be as small as possible. However, in adapter/tooth point assemblies of conventional designs reductions in such frontal cross-sectional area correspondingly weakens the assembly. Other design challenges include preventing undue operational stresses from being imposed on the wear member/support member connector apparatus, configuring the nose to reduce operational stress concentrations thereon, stabilizing each wear member against excess movement relative to its associated support member during excavating operations, and optimizing the abrasion protection provided to each support member by its associated wear member.
It would be desirable for both economic and operational reasons to provide an adapter/tooth point assembly having improvements in one or more of these design areas. It is to this goal that the present invention is primarily directed.
SUMMARY OF THE INVENTION
In carrying out principles of the present invention, in accordance with a preferred embodiment thereof, a specially configured excavating equipment wear member/support member assembly is provided which extends lengthwise along a front-to-rear assembly axis and representatively includes a replaceable tooth point, an intermediate adapter, and a main adapter. The tooth point is telescoped onto and captively retained on a forwardly projecting nose portion of the intermediate adapter, and the intermediate adapter is telescoped onto and captively retained on a forwardly projecting nose portion of the main adapter. The main adapter has a rear end portion which is releasably securable to a front edge portion of an excavating bucket lip.
The nose portion of the intermediate adapter projects forwardly from a front end surface of a rear base portion of the adapter, which representatively circumscribes the rear end of the nose portion, and has a horizontally elongated, generally elliptical cross-section along substantially its entire front-to-rear length, top and bottom surfaces, and horizontally opposite left and right surfaces. Horizontally opposite stabilizing projections are disposed on and project laterally outwardly from he left and right surfaces of the nose portion, and a connector opening extends horizontally through the nose portion and opens outwardly through the stabilizing projections. Preferably, the stabilizing projections are stabilizing bosses having rectangular configurations, are positioned adjacent the front end surface of the rear base portion of the intermediate adapter, and extend through only a relatively small portion of the front-to-rear length of the nose portion.
The intermediate adapter nose is complementarily received in a rear end cavity of the tooth point, with horizontally opposite connector openings extending through opposite left and right side walls of the tooth point into interior side recesses therein which complementarily receive the stabilizing bosses on the intermediate adapter nose. The tooth point connector openings are in an outwardly overlying align ed relationship with opposite ends of the intermediate adapter nose connector opening, and a connector structure, representatively a front connector pin, horizontally extends through the point and adapter connector openings and captively retains the tooth point on the intermediate adapter nose.
Preferably, the top and bottom surfaces of the intermediate adapter nose are substantially parallel to the front-to-rear assembly axis, and the top and bottom nose surfaces have front portions which are vertically inset from the balance of the top and bottom nose surfaces.
The main adapter has a rear base portion with a front end surface from which a nose portion forwardly projects, the main adapter nose portion having a configuration similar to that of the intermediate adapter nose, and is similarly provided with outwardly projecting stabilizing bosses on opposite left and right sides thereof, a connector opening extending horizontally through the main adapter nose and opening outwardly through its stabilizing bosses. The main adapter nose and its associated stabilizing bosses are complementarily received within a rear end cavity of the rear base portion of the intermediate adapter. The main adapter nose connector opening is aligned with left and right side wall connector openings formed in the base portion of the intermediate adapter, and a connector structure, representatively in the form of a rear connector pin, extends through the aligned connector openings and captively retains the intermediate adapter on the nose of the main adapter.
Facing front and rear end surfaces of the intermediate adapter base portion and the tooth point have alternately scalloped portions around their peripheries, the scalloped peripheries being complementarily engaged in an interlocking configurational relationship. Preferably, top and bottom portions of the front end surface of the rear base portion of the intermediate adapter have forwardly convex arcuate configurations, and left and right side portions of the front end surface of the rear base portion of the intermediate adapter have rearwardly concave arcuate configurations. In this manner, the front connector pin location may be advantageously positioned further rearwardly on the intermediate adapter.
In a similar manner, facing front and rear end surfaces of the main adapter base portion and the intermediate adapter have alternately scalloped portions around their peripheries, the scalloped peripheries being complementarily engaged in an interlocking configurational relationship. Preferably, top and bottom portions of the front end surface of the rear base portion of the main adapter have rearwardly concave arcuate configurations, and left and right side portions of the front end surface of the rear base portion of the main adapter have forwardly convex arcuate configurations. In this manner, top and bottom side portions of the intermediate adapter extend rearwardly over corresponding underlying portions of the main adapter and provide enhanced wear protection for the main adapter.
Compared to tooth point/adapter assemblies of conventional configurations, the complementary configurations of the adapter noses and their associated point and adapter cavities provide the tooth point/adapter assembly with a variety of advantages including smaller size with similar strength, reduced frontal area which facilitates assembly earth penetration, enhanced rotational stability among the tooth and adapter components, and reduced operational stresses on the connector pins. While the illustrated embodiment of the invention includes a two-piece adapter section, it will be readily appreciated by those of skill in this particular art that the adapter section could alternatively be defined, if desired, by a single adapter member. Additionally, while principles of the present invention have been representatively illustrated herein as being embodies in a tooth point and adapter assembly, it will further be appreciated by those of skill in this particular art that such principles could also be utilized to advantage in other types of excavating equipment wear member/support member assemblies as well.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of an excavating tooth point and adapter assembly embodying principles of the present invention;
FIG. 2 is a side elevational view of the assembly;
FIG. 3 is an exploded perspective view of the assembly;
FIG. 4 is an enlarged scale front end view of an intermediate adapter portion of the assembly;
FIG. 5 is an enlarged scale rear end view of a tooth point portion of the assembly;
FIG. 6 is an enlarged scale front end view of a main adapter portion of the assembly; and
FIG. 7 is an enlarged scale rear end view of the intermediate adapter.
DETAILED DESCRIPTION
Referring initially to FIGS. 1-3, the present invention provides a specially configured excavating tooth point and adapter assembly 10 which representatively includes a replaceable tooth point 12 , an intermediate adapter 14 , a main adapter 16 , a first connector structure illustratively in the form of a schematically depicted connector pin 18 , and a second connector structure illustratively in the form of a schematically depicted connector pin 20 . The assembly 10 is elongated in a front-to-rear direction along a longitudinal axis 22 , and is anchored to and projects forwardly beyond a front edge portion of a bottom excavating bucket lip 24 , a small section of which is illustrated in phantom in FIGS. 1 and 2. Assembly 10 is one of a spaced, parallel series of such assemblies (the other ones of which are not illustrated) similarly attached to and projecting forwardly beyond the lip 24 .
With reference now to FIGS. 1-4 and 7 , the intermediate adapter 14 has a rear base portion 26 and a front nose portion 28 . Base portion 26 has a front end surface 30 from which the nose 28 forwardly projects, a rear end surface 32 inwardly through which a cavity 34 extends, top and bottom walls 36 and 38 , and left and right side walls 40 and 42 . Aligned connector openings 44 and 46 respectively extend through the left and right side walls 40 and 42 into the cavity 34 . The front end surface 30 of the adapter base 26 is alternately scalloped in a front-to-rear direction around its periphery, with the top and bottom portions 30 a, 30 b of the front end surface 30 being convexly curved in a forward direction, and the left and right portions 30 c, 30 d of the front end surface 30 being concavely curved in a rearward direction. Similarly, the rear end surface 32 of the adapter base 26 is alternately scalloped in a front-to-rear direction around its periphery, with the top and bottom portions 32 a, 32 b of the rear end surface 32 being convexly curved in a rearward direction, and the left and right portions 32 c, 32 d of the rear end surface 32 being concavely curved in a forward direction.
The intermediate adapter nose 28 has, along its front-to-rear length, a horizontally elongated elliptical cross-section, with top and bottom surfaces 48 , 50 and left and right side surfaces 52 and 54 . Except for a slight draft angle of 5 degrees or less, the top and bottom surfaces 48 , 50 are substantially parallel to the assembly axis 22 . At the front end of the nose 28 is a reduced cross-section stabilizing tip 56 having a horizontally elongated elliptical cross-section and top and bottom surfaces 58 and 60 which are also substantially Parallel to the assembly axis 22 . Laterally outwardly projecting stabilizing bosses 62 and 64 are respectively formed on the left and right side surfaces 52 , 54 of the adapter nose 28 at their junctures with the front end surface 30 of the adapter base 26 . A connector opening 66 horizontally extends through the adapter nose 28 and opens outwardly through the bosses 62 and 64 .
With reference now to FIGS. 1-3 and 5 , the point 12 has a suitable cutting edge 68 formed on its front end, a rear end surface 70 through which a cavity 72 inwardly extends, top and bottom walls 74 and 76 , and left and right side walls 78 and 80 through which aligned connector openings 82 , 84 respectively extend into the interior of the cavity 72 . The rear end surface 70 is alternately scalloped around its periphery, having top and bottom portions 70 a, 70 b which are concavely curved in a forward direction and have curvatures respectively complementary to those of the previously described front end surface portions 30 a, 30 b of the intermediate adapter base 26 , and left and right side portions 70 c, 70 d which are convexly curved in a rearward direction and have curvatures respectively complementary to those of the previously described front end surface portions 30 c, 30 d of the intermediate adapter base 26 .
Tooth point 12 is replaceably mounted on the intermediate adapter nose 28 by first placing the nose 28 within the tooth point cavity or pocket 72 , thereby bringing the point connector openings 82 , 84 into outwardly overlying alignment with opposite ends of the horizontally oriented adapter nose opening 66 , and then operatively inserting the front connector pin 18 in the aligned connector openings 66 , 82 , 84 . The inserted connector pin 18 is suitably retained in such openings, in a conventional manner not pertinent to the present invention, and functions to captively and releasably retain the point 12 on the intermediate adapter 14 , the point 12 serving as a wear member for the intermediate adapter 14 which, in turn, may be characterized as a support member for the mounted point 12 .
The tooth point cavity 72 (see FIG. 5) has an interior surface configuration complementary to that of the exterior surface of the intermediate adapter nose 28 which it releasably receives. Specifically, the cavity 72 has a portion 28 a configured to complementarily receive the body of the inserted intermediate adapter nose 28 , and left and right interior side wall recesses 62 a, 64 a that respectively and complementarily receive the inserted adapter nose stabilizing bosses 62 , 64 . connector openings 82 , 84 respectively extend laterally inwardly into the recesses 62 a, 64 a.
The unique shapes of the tooth point 12 and intermediate adapter 14 provide the tooth point/intermediate adapter subassembly 12 , 14 with a variety of advantages compared to conventional point/adapter assemblies. For example, the horizontally elongated elliptical cross-sectional shape along its length of the intermediate adapter nose 28 substantially eliminates planar areas on the nose 28 , thereby correspondingly reducing undesirable stress concentration areas thereon. This, coupled with the substantially axially extending top and bottom surfaces 48 and 50 of the nose 28 , permits the nose 28 to be smaller than noses with conventional configurations without appreciably reducing its operational strength. This, in turn, provides the point/adapter subassembly 12 , 14 with a correspondingly smaller frontal area that gives it improved earth penetration efficiency.
Coupled with the interfit between the nose bosses 62 , 64 and the point pocket recesses 62 a and 64 a, the interfit between the stabilizing tip 56 of the nose 28 and the corresponding point pocket surface area provides the mounted tooth point 12 with substantially enhanced stability against operational rotation relative to the intermediate adapter 14 about the assembly axis 22 . This anti-rotational stability is further enhanced by the substantially horizontally extending top and bottom nose surfaces 48 and 50 behind the stabilizing tip 56 . Moreover, the horizontal orientation of the elongated connector structure 18 places it on the “neutral” axis of the nose 28 (from the standpoint of tensile and compressive nose bending stresses), thereby desirably lessening the operational stresses imposed on the installed connector 18 . The substantially horizontally extending top and bottom side surfaces 48 , 50 of the nose 28 further reduce the operating loads on the connector structure 18 .
As can best be seen in FIGS. 1 and 2, with the tooth point 12 operatively and releasably installed on the intermediate adapter 14 , the alternately scalloped rear end surface 70 of the point 12 is complementarily engaged in an interlocked fashion with the alternately scalloped front end surface 30 of the base portion 26 of the intermediate adapter 14 . This unique arcuately scalloped interfit serves to stabilize the point 12 against rotation about the axis 22 relative to the intermediate adapter 14 . Additionally, the rearward scalloping of the front end surface portions 30 c, 30 d on the adapter base 26 advantageously permits the placement of the connector structure 18 further back on the adapter 14 to a somewhat thicker and thus somewhat stronger location thereon.
The interfit between the intermediate adapter 14 and the main adapter 16 is similar to the interfit between the point 12 and the intermediate adapter 14 . Specifically, and with reference now to FIGS. 1-3, 6 and 7 , the main adapter 16 has a rear base portion 86 and a front nose portion 88 . Base portion 86 has a front end surface 90 from which the nose 88 forwardly projects, and vertically spaced apart top and bottom rearwardly extending mounting legs 92 , 94 which define therebetween a cavity 96 that receives a portion of the bucket lip 24 . Legs 92 , 94 are 35 respectively welded or otherwise anchored to the top and bottom sides of the bucket lip 24 to operatively support the main adapter 16 on the bucket lip 24 . The front end surface 90 of the main adapter base 86 is alternately scalloped in a front-to-rear direction around its periphery, with the top and bottom portions 90 a, 90 b of the front end surface 90 being concavely curved in a rearward direction, and the left and right portions 90 c, 90 d of the front end surface 90 being convexly curved in a forward direction.
The main adapter nose 88 has, along its front-to-rear length, a horizontally elongated elliptical cross-section, with top and bottom surfaces 98 , 100 and left and right side surfaces 102 , 104 . Except for a slight draft angle of 5 degrees or less, the top and bottom surfaces 98 , 100 are substantially parallel to the assembly axis 22 . At the front end of the nose 88 is a reduced cross-section stabilizing tip 106 having a horizontally elongated elliptical cross-section and top and bottom surfaces 108 and 110 which are also substantially parallel to the assembly axis 22 . Laterally outwardly projecting stabilizing bosses 112 and 114 are respectively formed on the left and right side surfaces 102 , 104 of the adapter nose 88 at their junctures with the front surface 90 of the adapter base 86 . A connector opening 116 horizontally extends through the adapter nose 88 and opens outwardly through the bosses 114 and 116 .
The intermediate adapter 14 is replaceably mounted on the main adapter nose 88 by first placing the nose 88 within the intermediate adapter rear cavity or pocket 34 , thereby bringing the intermediate adapter connector openings 44 , 46 into outwardly overlying alignment with opposite ends of the horizontally oriented main adapter nose opening 116 , and then operatively inserting the rear connector pin 20 in the aligned connector openings 44 , 46 , 116 . The inserted connector pin 20 is suitably retained in such openings, in a conventional manner not pertinent to the present invention, and functions to captively and releasably retain the intermediate adapter 14 on the main adapter 16 , the intermediate adapter serving as a wear member for the main adapter 16 which, in turn, may be characterized as a support member for the mounted intermediate adapter 14 .
The intermediate adapter cavity 34 (see FIG. 7) has an interior surface configuration complementary to that of the exterior surface of the main adapter nose 88 which it releasably receives. Specifically, the cavity 34 has a portion 88 a configured to complementarily receive the body of the inserted main adapter nose 88 , and left and right interior side wall recesses 112 a, 114 a that respectively and complementarily receive the inserted main adapter nose stabilizing bosses 112 and 114 . Connector openings 44 , 46 respectively extend laterally inwardly into the recesses 112 a, 114 a.
The unique shapes of the intermediate adapter 14 and the main adapter 16 provide the intermediate adapter/main adapter subassembly 14 , 16 with a variety of advantages compared to conventional excavating wear member/support member assemblies. For example, the horizontally elongated elliptical cross-sectional shape of the adapter nose 88 substantially eliminates planar areas on the nose 88 , thereby correspondingly reducing undesirable stress concentration areas thereon. This, coupled with the substantially axially extending top and bottom surfaces of the nose 88 , permits the nose 88 to be smaller than noses with conventional configurations without appreciably reducing its operational strength. This, in turn, provides the intermediate adapter/main adapter subassembly 14 , 16 with a correspondingly smaller frontal area that gives it improved earth penetration efficiency.
Coupled with the interfit between the nose bosses 112 , 114 and the point pocket recesses 112 a and 114 a, the interfit between the stabilizing tip 106 of the nose 88 and the corresponding intermediate adapter pocket interior surface area provides the mounted intermediate adapter 14 with a substantially enhanced stability against operational rotation relative to the main adapter 16 about the assembly axis 22 . This anti-rotational stability is further enhanced by the substantially horizontally extending top and bottom nose surfaces 108 and 110 behind the stabilizing tip 106 . Moreover, the horizontal orientation of the elongated connector structure 20 places it on the “neutral” axis of the nose 88 (from the standpoint of tensile and compressive nose bending stresses), thereby desirably lessening the operational stresses imposed on the installed connector structure 20 . The substantially horizontally extending top and bottom surfaces 108 , 110 of the nose 88 further reduce the operating loads on the connector structure 20 .
As can best be seen in FIGS. 1 and 2, with the intermediate adapter 14 operatively and releasably installed on the main adapter 16 , the alternately scalloped rear end surface 32 of the intermediate adapter 14 is complementarily engaged in an interlocked fashion with the alternately scalloped front end surface 90 of the base portion 86 of the main adapter 16 . This unique arcuately scalloped interfit serves to stabilize the intermediate adapter 14 against rotation about the axis 22 relative to the main adapter 16 about the assembly axis 22 . Additionally, the rearward scalloping of the front end surface portions 90 a, 90 b on the main adapter base 86 advantageously positions top and bottom rear wall portions of the intermediate adapter 14 in an overlying, abrasion-protecting relationship with corresponding front top and bottom portions of the main adapter 16 thereby desirably increasing the operating life of the main adapter 16 .
While the excavating tooth point and adapter assembly 10 has been representatively depicted herein as including a two piece adapter section, it will be readily appreciated by those of skill in this particular art that the two adapter portions 14 and 16 Could be replaced with a single adapter member if desired. Additionally, while the assembly 10 has been representatively depicted herein as being defined by point and adapter structures, it could be alternatively formed from other types of associated wear and support members if desired.
The foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims. | An elongated excavating tooth assembly includes a replaceable tooth point and an adapter structure comprising (1) an intermediate adapter having a front end nose complementarily received in a rear end pocket of the point and captively retained therein by a first connector pin structure, and (2) a main adapter having a front end nose complementarily received in a rear end pocket of the intermediate adapter and captively retained therein by a second connector pin structure, and a rear end operatively securable to an excavating bucket lip. Special configurations of the point and adapter portions of the assembly, including horizontally elongated oval configurations of the noses, horizontal orientation of the connector pins, nose stabilization bosses at the nose connector openings, and complementarily scalloped adapter and point interface areas, provide the assembly with reduced size and improved strength, wear and operational characteristics. | 4 |
BACKGROUND INFORMATION
[0001] This invention relates to a meter for motorcycles or the like, and in particular to an approach to connecting the individual wires of a wire bundle to an indicator dashboard or similar meter (hereafter collectively referred to as “dashboard”) that is mounted to the motorcycle bar for displaying information (speed, temperature, etc.).
[0002] The wire bundle comprises several insulated wires that emanate from connections to detectors or sensors that are located on the vehicle away from the dashboard. The wires are bundled within a protective outer sheath. The end of the sheath enters the dashboard case and the individual wires are connected in some manner to the main circuit board of the dashboard.
[0003] FIG. 1 illustrates a prior art approach for connecting the individual wires of a wire bundle to an indicator dashboard. The case 1 of the dashboard is typically mounted in front of the motorcycle bar to enable easy viewing of the dashboard display by a rider.
[0004] A battery 6 is secured in a mounting in the case by a cover 7 and O-ring 5 . The case 1 includes and interior 12 that houses the main circuit board and associated display components. FIG. 1 shows the bottom of the case housing 13 and a resilient seal 3 that fits between the housing and a case cover (not shown) that includes a transparent lens for viewing the display that is housed in the case.
[0005] A wire bundle 11 is enclosed in a protective sheath 10 and enters an opening in the back of the case 1 . As shown in the exploded view of FIG. 1 , the termini of these wires 11 (hereafter sometimes referred to as “entry” wires) are connected to the underside of an interface printed circuit board (PCB) 2 . Near one edge of that PCB, the ends of several, smaller “internal” wires 15 are joined to the upper surface of the interface PCB 2 . The internal wires 15 are bent to extend away from and generally parallel to the plane of the PCB. The outer ends of the internal wires 15 are crimped into a connector 14 that connects to the main circuit board (not shown) that is carried inside the case.
[0006] As part of the assembly process for this device, the PCB 2 is seated inside of a well 16 that is defined in the interior 12 of the case 1 . The well 16 is a compartment that is defined by the back wall of the case and by four, inwardly projecting thin sidewalls 17 that define a cubical volume within which the PCB 2 is secured. The wire bundle 11 extends through the opening in the back wall of the meter case to protrude inside the well 16 , for connection to the interface PCB as noted above. The well 16 is filled with epoxy for the purpose of providing strain relief and preventing water from migrating into the case.
[0007] The prior art assembly process for connecting the internal wires 15 between the upper surface of the interface PCB 2 and the main circuit board, as noted above, requires soldering of the ends of the wires 15 to the PCB and crimping the other ends of the wires into a connector that is in turn inserted into the mating connector carried on the main circuit board. To accomplish the insertion, and to facilitate handling of the wires 15 during assembly, the length of the wires between the PCB and connector 14 is made slightly longer than the distance between the wire ends at the PCB and the connector when finally assembled. Accordingly, each of the wires is necessarily bent slightly during and after assembly. Controlling the final configuration of the bends is difficult because each individual wire is free to buckle in any direction (upwardly, downwardly or sideways). Sideways buckling can be particularly troublesome because such a “stray” buckled wire can obstruct assembly or hinder connection of other components within the compact dashboard case. Thus, extra assembly time and cost is required to carefully control the buckling direction of all of the wires to avoid strays.
[0008] The prior art device is also susceptible to failure attributable to vibration and penetration of moisture into the case. In particular, the solder joints of the internal wires can be stressed by the continuous vibration occurring during operation of the motorcycle, and eventually separate from the PCB 2 at the location where the wire ends are soldered to the PCB. One way to address this problem is to reduce the mass of the wires (hence reduce the damaging energy transmitted via vibration) by using very small diameter wires. However, when wires are connected to the PCB using modern lead-free solders, the attendant higher melting points of such solders calls for relatively stiffer insulating jackets over the wire than is required with lead-based solders. The stiffer insulation in turn increases the overall mass of the wires, and thus returns the damaging vibration problem.
[0009] Finally, despite the presence of sealing epoxy in the well 16 mentioned above, some moisture may penetrate the well, and the presence of the internal wires that extend from the PCB in the well to the connector 14 on the main circuit board provide between the wires a capillary path for the moisture to flow to the connector 14 and damage the main circuit board.
[0010] This capillary flow seems to be enhanced by the presence of an array of grooves 20 formed in the upper edge of the prior art sidewall 17 over which the internal wires 15 pass, each groove receiving a wire.
SUMMARY OF THE INVENTION
[0011] The invention disclosed here provides an apparatus for conducting signals from several signal-carrying, bundled wires to a circuit member that is mounted within the interior of a sealed case, and in particular an assembly for conducting the signals while providing a robust, compact and water-resistant connection between the internal main circuit and the entry wires.
[0012] Also provided is a robust method of conducting signals from several signal-carrying wires to a circuit member that is mounted within the interior of a sealed case.
[0013] Other advantages and features of the present invention will become clear upon study of the following portion of this specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is an assembly view of components used in a prior art technique for connecting a wire bundle inside of a dashboard.
[0015] FIG. 2 is a perspective view, with an enlarged detail showing a preferred embodiment of the connection technique of the current invention. FIG. 2 shows the underside of a conductor assembly component of the present invention.
[0016] FIG. 3 is a perspective, top view of the conductor assembly component.
[0017] FIG. 4 is a cut-away, top perspective view of a dashboard case with which the preferred connection technique of the current invention is implemented.
DETAILED DESCRIPTION
[0018] FIGS. 2-4 illustrate a preferred embodiment of the present invention. FIG. 2 includes a perspective view and an enlarged detail showing the underside of a conductor assembly 22 component of the present invention. The conductor assembly 22 includes a rigid portion 24 which can be formed of conventional printed circuit board material.
[0019] The rigid portion 24 is planar and generally square shaped. As seen in FIG. 4 , the rigid portion 24 fits inside of a cubical well 16 that is a compartment formed in the interior 12 of the case 1 . The well 16 is defined by four, inwardly projecting thin sidewalls 17 that define the cubical volume within which the rigid portion 24 is seated. The back of the dashboard case defines a protruding cylinder 30 that includes a bore or opening 32 through which the sheath 10 of the wire bundle extends.
[0020] As best shown in FIG. 4 and the detail view of FIG. 2 , the individual wires 11 of the wire bundle terminate at the underside of the rigid portion 24 of the conductor assembly 22 ( FIG. 2 ). The exposed terminus of each wire 11 passes into a through-hole in the conductor assembly 22 and is soldered to a flanged, conductive sleeve 34 that lines the hole to thus electrically connect the wires 11 with conductive traces 36 ( FIG. 4 ) that are printed on the upper surface of a flexible portion 23 of the conductor assembly.
[0021] The flexible portion 23 of the conductor assembly 22 is preferably a flexible plastic substrate having the conductive traces 36 printed thereon. The flexible portion 23 is, like the rigid portion 24 , planar in the sense that it is a thin, ribbon-like member having flat upper and lower surfaces. In this embodiment, the flexible portion 23 overlays and is bonded to the rigid portion 24 . At one edge of the rigid portion 24 , the flexible portion 23 extends away from the rigid portion to a remote end 38 ( FIG. 3 ) that is configured for attachment to the main circuit board of the dashboard.
[0022] With reference to FIG. 4 , the thin, ribbon-like flexible portion 23 of the conductor assembly is a unitary element, the bending behavior of which is readily controlled (as opposed to the unpredictable, individualized buckling of the several, separate internal wires 15 as discussed above). The flexible portion 23 most readily bends in a direction transverse to its long axis, such as shown at bends 42 in FIG. 4 . Problematic sideways buckling or bending (as discussed above) of the flexible portion is thus quite unlikely during the assembly process Importantly, the combination of the relatively low mass of the flexible portion 23 (as compared to that of the prior art internal wires 15 ) and the elimination of soldered internal-wire-to-PCB connections effectively eliminates the damaging vibration problem of the prior art.
[0023] Moreover, the composition of the flexible portion is such that it holds its shape once bent. This feature thus enables the flexible portion 23 to be bent at specific locations before or during assembly (such as bends 42 in FIG. 4 ) so that once connected, the flexible portion 23 will readily assume a predicted location within the case. For instance, the controlled location of the bends 42 shown in FIG. 4 results in the formation of a predictably sized and located trough-like volume into which volume other internal components can located within the compact dashboard case 1 .
[0024] The flexible portion 23 conforms to the shape of a sidewall 17 of the well and extends across a flat, smooth upper edge of a sidewall 17 . That is, unlike the prior art, the flat upper edge of the wall 17 over which the flexible portion 23 passes has no grooves or other irregularities that might provide gaps between the flexible portion 23 and wall 17 , which gaps could enable moisture that may enter the well to penetrate outside of the well 16 and to the main circuit board as described above with respect to the prior art.
[0025] Once the flexible portion 23 of the conductor assembly 22 is properly located as shown in FIG. 4 , fasteners that extend through holes 40 provided through the conductor assembly 22 are used to anchor an end of the conductor assembly (that is, the rigid portion 24 and overlying part of the flexible portion 23 ) to the interior of the well 16 . A square flat cover plate (not shown) that conforms to the shape of the well 16 is then secured over the upper edges of the well sidewalls 17 to enclose the well, which is filled with epoxy to seal the well and provide strain relief to the wire junctions.
[0026] It is noteworthy that the planar flexible portion 23 thus passes between the substantially flat, opposed surfaces of the sidewall 17 and cover plate, thereby allowing the flexible portion to extend from the well without creating any gaps for enabling moisture to move out of the well in the event that the epoxy seal fails or is damaged in a manner that allows outside moisture to enter the well. | A robust and waterproof wires-to-meter connection that provides an apparatus for conducting signals from several signal-carrying, bundled wires to a circuit member that is mounted within the interior of a sealed case, and in particular an assembly for conducting the signals while providing a robust, compact and water-resistant connection between the internal main circuit and the entry wires. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to apparatus for drying clothes. In particular, the invention relates to a dryer utilizing pressure below atmospheric pressure for speeding the drying process.
2. Description of the Related Art
At reduced pressures, the boiling point of liquids such as water decreases. This phenomenon can been applied to the task of drying clothes. Advantages include lower drying temperatures and reduced drying times.
U.S. Pat. No. 5,357,771, issued to Schaal, discloses an apparatus utilizing dry cleaning solvent instead of water for washing clothes. This same apparatus also dries the clothes by reducing pressure in the cleaning chamber. A vacuum is used to reduce the solvent boiling point for safety reasons. The device is designed for use in the dry cleaning industry, and cannot be operated by the average consumer at home. The apparatus is too complex and expensive for the consumer market, because of the equipment and materials required to keep the solvent from exploding.
A need remained for a clothes dryer that dries clothes in less time and at lower temperature. A dryer that minimizes secondary heating of the surrounding environment was also desired.
SUMMARY OF THE INVENTION
The general object of the invention is to dry clothes more quickly and with less energy consumption than conventional clothes dryers. Another object of the invention is to dry clothes at lower temperatures than conventional clothes dryers, so that fabric shrinkage and other undesirable effects are minimized. A third object is to minimize heating of the surrounding environment by the dryer.
In general, these objects are achieved by a drum with a door that forms an airtight seal with the drum, a vacuum line running from the drum to a vacuum pump, a vacuum shutoff valve for allowing the flow of air out of the drum to the vacuum pump, and a pressure equalization valve, for restoring atmospheric pressure inside the drum. In one embodiment, the drum is made of a material such as polycarbonate resin, and infrared lamps are positioned about the circumference of the drum to heat the clothes through the drum. In an alternative embodiment, the drum is made of metal, and a number of cold junction diodes provide the means for heating the clothes. Cold junction diodes are semiconductor diodes exhibiting Peltier effect characteristics. A heat sensor is installed within the vacuum line at the point where the vacuum line enters the drum, and monitors the temperature of air leaving the drum. The temperature measurement from the heat sensor is used to regulate the heat output of the lamps (or diodes).
By reducing the pressure inside the drum to about 1.5 pounds per square inch absolute (10.3 kPa absolute), drying temperatures of about 115° Fahrenheit (46° Celsius) can be employed. Drying time is still shorter than a conventional dryer running at 150° Fahrenheit (66° Celsius). The lower drying temperatures reduce secondary heating of the surrounding environment, and reduce shrinking of the clothes.
The above, as well as additional objects, features, and advantages of the invention will become apparent in the following detailed description and in the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic rear elevation of a clothes dryer according to the invention, omitting mounting and support elements, cabinet and other elements well known in the industry.
FIG. 2 is a right side elevation thereof.
FIG. 3 is a left side elevation thereof.
FIG. 4 is cross-sectional view of the drum, taken along lines 4--4 in FIG. 2.
FIG. 5 is a cross-sectional right side elevation detail of the rear bearing assembly.
FIG. 6 is a cross-sectional side elevation detail of the cold junction diode/paddle assembly used in an alternative embodiment.
FIG. 7 is an end elevation detail thereof, showing installation on the drum.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIGS. 1-3, the clothes dryer 11 includes a drum 13, a vacuum pump 15, a bearing 17 supporting the drum 13, a vacuum line 19, a vacuum shutoff valve 21, and a pressure equalization valve 23. The drum 13 is about two feet (sixty centimeters) in diameter and is made of polycarbonate resin of sufficient thickness to withstand a perfect vacuum (i.e. zero psi absolute) inside the drum 13, with normal atmospheric pressure outside the drum 13. The drum 13 has an open end 25 and a closed end 27. A door 29 is pivotably attached to the open end 25 of the drum 13. The door 29 and drum 13 form an airtight seal when the door 29 is closed and secured in place.
The vacuum line 19 connects the interior of the drum 13 to the vacuum pump 15. The vacuum pump 15 is capable of reducing the pressure inside the drum 13 to 0.37 psi absolute (2.55 kPa).
The bearing 17, as shown in detail in FIG. 5, passes through a hole (not shown) in the center of the closed end 27 of the drum 13, and is secured to the drum 13, forming an airtight seal. The vacuum line 19 in turn passes through the bearing 17. Three rubber seals 31, separated by metal spacers 33, form an airtight seal between the vacuum line 19 and the bearing 17. The vacuum line 19 is prevented from excessive movement relative to the drum 13 by two items: a hold down nut 35, and a thrust washer 37 that is tack welded to the vacuum line 19. A heat sensor 39 is installed in the vacuum line 19 just outside the bearing 17 to measure the temperature of air leaving the drum 13.
As shown in FIGS. 2 and 3, a filter 41 in the vacuum line 19 removes lint from the air extracted from the drum 13 before it can enter the vacuum pump 15. The filter 41 uses a standard drip-type coffee maker filter paper (not shown) as its filter element.
Two valves are installed in the vacuum line 19: the vacuum shutoff valve 21 and the pressure equalization valve 23. A vacuum shutoff valve 21 is located in the vacuum line 19 between the drum 13 and the filter 37. The shutoff valve 21 closes the drum 13 off from the vacuum pump 15 during operation, as will be described. The shutoff valve 21 is closed when deenergized and open when energized. A tee 43 is located in the vacuum line 19 near the drum 13. One branch of the vacuum line 19 coming from the tee 43 goes to the vacuum shutoff valve 21. The other branch of the vacuum line 19 coming from the tee 43 goes to the pressure equalization valve 23. The inlet of the pressure equalization valve 23 is open to the surrounding atmosphere. The equalization valve 23 restores atmospheric pressure inside the drum 13 at the end of operation. The shutoff valve 21 is open when deenergized and closed when energized.
An electric motor 45 drives the vacuum pump 19 via a clutch (not shown). The motor 45 also turns a belt pulley 47 via a clutch 49. The belt pulley 47 drives a belt 51 that turns the drum 13 to tumble wet clothes (not shown) inside the drum 13. A tension pulley 53 maintains the proper tension in the belt 51 by equipment not shown in the figures.
Four infrared quartz lamps 55, in the 200 to 500 watt power range, are positioned around the drum 13 in a square pattern. Each lamp 55 is partially surrounded by a housing 57 that traps some of the air around each lamp 55. The heat of the lamps 55 radiates through the drum 13, heating the contents. In addition, an induction heater 59 can be employed to provided quick initial heating of the drum contents if there are no metallic objects inside, such as rivets or buttons.
The four housings 57 connect to a header 61 that connects in turn to a hot air line 63. The hot air line 63 connects, via a hot air valve 65, to the vacuum line 19 at a point between the vacuum shutoff valve 21 and the drum 13. The hot air valve 65 is closed when deenergized. The hot air trapped by the housings 57 is used in the drying cycle as described below.
The interior of the drum 13, as shown in FIG. 4, includes four paddles 67, which can be molded in a single piece with the drum 13. Eight moisture purge valves 69 are installed in the drum 13, adjacent to the paddles 67. One side of each purge valve 69 connects to the drum interior via a passage 71 passing through a paddle 67. Each purge valve 69 has a poppet-type plug 73 made of ferromagnetic material. A spring (not shown) biases the valve plug 73 against the valve seat 75 to close the valve 69. A solenoid 76 is installed within each of the lamp housings 55, as seen in FIG. 1. The purge valves 69 are aligned so as to pass under the solenoid 76 as the drum 13 turns. During the drying cycle, the solenoids 76 are continuously energized during certain intervals. Each valve plug 73 will be pulled up, off its seat 71, as it passes by a solenoid 76. Thus, short bursts of air will flow into the drum 13, via the purge valves 69, when the solenoids 76 are energized. The solenoids 76 must be capable of opposing the combined force of a) the pressure differential across the purge valve 69 with a vacuum inside the drum 13, and b) the spring force (not shown). The purge valves 69 should be sized with respect to the capacity of the vacuum pump 15, so that the vacuum pump 15 can maintain the desired pressure in the drum 13.
Operation of the clothes dryer 11 will now be described. Clothes are put in the drum 13 and the door 29 is closed and sealed. A timer (not shown) is turned on, whereupon the vacuum shutoff valve 21, the pressure equalization valve 23, the motor 45, the vacuum pump clutch (not shown), the pulley clutch 49, and the quartz lamps 55 are energized. The induction heater 59 can also be energized at this time, provided there are no metal objects inside the drum 13. The induction heater 59 is run for about three minutes, and then shut off.
The vacuum pump 15 is run with the vacuum shutoff valve 21 open, during which the heat sensor 39 keeps the air leaving the drum 13 at a temperature between 110° and 150° Fahrenheit (43°and 66° Celsius) by turning the quartz lamps 55 on and off as needed. The desired temperature can be selected by the user. When six minutes have passed, the solenoids 76 are energized and the moisture purge valves 69 begin allowing bursts of ambient air into the drum 13. After another ten minutes has passed, the vacuum shutoff valve 21 is closed, the solenoids 76 for the moisture purge valves 65 are deenergized, and the hot air valve 65 is opened. Hot air is drawn away from the lamps 55 and into the drum 13. The hot air valve 65 is kept open from thirty to forty-five seconds and then closed. At the same time, the vacuum shutoff valve 21 is opened.
Opening the shutoff valve 21 causes a rapid, almost instantaneous decompression of the drum, along with an attendant "shock" removal of moisture from the clothes. The equipment between the shutoff valve 21 and the vacuum pump 15 should be sized so that its total internal volume is a significant percentage of the drum's 13 interior volume, preferably greater than five percent, to ensure this rapid decompression.
When the vacuum shutoff valve 21 has been open for six minutes, the solenoids 76 in the lamp housings 57 are again energized, causing the moisture purge valves 69 to open in short bursts. At the same time, the quartz lamps 55 are turned off completely. When five more minutes have elapsed, the motor 45, the vacuum pump clutch 49, and the pulley clutch (not shown) are deenergized, and the pressure equalization valve 23 is opened, restoring atmospheric pressure to the interior of the drum 13. This completes the drying cycle.
An alternative drying cycle is envisioned for drying woolen sweaters and other delicate items. The cycle is substantially identical to the regular cycle, except that the pulley clutch (not shown) is not energized, so that the drum 13 will not turn. Also, the temperature measured by the heat sensor 39 is kept below 115° Fahrenheit (46° Celsius) to prevent excessive heating that can cause shrinking and wrinkling of the items.
An alternate embodiment is envisioned for commercial applications, such as clothes dryers for hotels. In this embodiment, the drum 13 is made of metal and has a diameter of about 4 feet (122 cm). Because the drum 13 is made of metal, the quartz lamps 57 and induction heater 59 employed in the preferred embodiment cannot be used. FIGS. 6 and 7 illustrate the heating means for this embodiment. Metal paddles 77 are mounted to the inside of the drum 13, with an intervening layer of thermal insulation 79. A number of cold junction diodes 81 mount on a heat sink 83, pass through the drum 13, and make secure mechanical and electrical contact with the paddle 77. A temperature sensor 85 installed in the paddle 77 monitors the paddle temperature to prevent damage to the diodes 81 from overheating. Each diode 81 receives power from a common power supply wire 87 via a current limiting resistor 89. The paddle 77 provides the common ground connection for the diodes 81. Passages 91 in the paddle 77 connect to the moisture purge valves (not shown), which can be located, along with their corresponding solenoids 76 in a convenient location. The diodes 81 are powered by direct current, the direction of the current causing the side of the diode 81 connected to the paddle 77 to become hot, and the side mounted on the heat sink 83 to become cold. The heat sink 83 will therefore draw heat out of the surrounding environment, which will partially offset the heating of the environment by the dryer 11 during normal operation.
The clothes dryer of the invention has several advantages over the prior art. The clothes dryers consumes less power because of lower air temperatures required. In fact, a compact model, designed for apartments or smaller loads, could be designed that is capable of working from standard 120 VAC wall power, rather than the 240 VAC, three-phase power normally required for electrically heated clothes dryers. The lower operating temperatures reduce shrinking and wrinkling of clothes. The total drying cycle time is shorter, despite using less power and lower temperatures.
The invention has been shown in two embodiments. It should be apparent to those skilled in the art that the invention is not so limited, but is susceptible to various changes and modifications without departing from the spirit of the invention. | A rotatable drum forms an airtight seal with a door. A vacuum line connects the interior of the drum to a vacuum pump. A shutoff valve closes the vacuum line to the pump. A pressure equalization valve connects the drum to the outside atmosphere. A bearing supports the drum, in combination with the vacuum line. Infrared lamps heat clothes placed inside the drum. The vacuum pump reduces the air pressure in the drum below atmospheric pressure, reducing the evaporation temperature of the water in the clothes. A heat sensor measures the temperature of the air leaving the drum. Solenoid-driven purge valves allow air to enter the drum in short bursts, thus aiding the drying of the clothes. | 3 |
This is a continuation of application Ser. No. 268,982, filed Nov. 9, 1988, now abandoned.
This is a division of application Ser. No. 137,601, filed Dec. 24, 1987, now U.S. Pat. No. 4,802,347.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to automatic washers and more particularly to an improved arrangement for activating a basket brake for an automatic washer.
2. Description of the Prior Art
In automatic washers it is standard practice to apply a brake to the wash basket during certain periods of a wash cycle, such as during an agitate mode so that the basket is held stationary relative to an oscillating agitator. At other times in the wash cycle it is desirable to permit the basket to rotate, such as during a period while wash liquid is being pumped from the basket, such as during a spin dry mode.
To operate the brake which oftentimes is in the form of a band surrounding a hub which rotates with the basket, a solenoid is used wherein the brake band is generally biased into an engaging position when the solenoid is off, so that in the event of a power outage this results in the brake being on. The solenoid overcomes the spring bias and moves the brake band into an off or release position.
A solenoid is a fairly expensive electrical component and it would be advantageous if the brake could be controlled without resort to the use of this separate component.
U.S. Pat. No. 4,375,587 discloses a motor having either an axially displaceable rotor or an axially displaceable pole piece, both of which are caused to move by magnetic attraction when the motor is energized to accuate a switch. Other patents disclosing axially displaceable rotors include U.S. Pat. Nos. 2,591,510; 3,184,933 and 2,694,781.
SUMMARY OF THE INVENTION
The present invention provides an improved motor construction which, in one embodiment of use provides a means for activating and deactivating a band brake for an automatic washer which obviates the need for a separate electrical component such as a solenoid to operate the brake.
The improved motor construction provides that a portion of the field or stator of the motor be displaceable relative to the rotor in either a sliding or pivotable manner. This portion of the stator is normally biased into the displaced position, but upon energization of the motor the attractive magnetic forces overcome the displacing bias and draw the stator into close proximity to the rotor. A linkage is provided between the displaceable stator and the brake band so that displacement of the stator toward the rotor disengages the brake.
In automatic washers it is desirable to release the basket from restraint against rotation when a pump is pumping water from the washing machine, but at all other times it is desirable to have the basket restrained against rotation. Therefore, a separate motor having a displaceable stator can be provided for the pump to discharge water from the washing machine and, when this separate motor is activated, the basket brake will be disengaged. At all other times the brake will be biased into engagement therefore preventing rotation of the basket.
It will be appreciated that the present invention of a displaceable stator has utility and applications other than use in an automatic washer although the invention has particular utility in such an arrangement.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an automatic washer embodying the principles of the present invention.
FIG. 2 is a partial side sectional view through a lower portion of an automatic washer.
FIG. 3 is a sectional view taken generally along the line III--III of FIG. 2.
FIG. 4 is a schematic illustration of a first embodiment of the invention.
FIG. 5 is a schematic illustration of a motor incorporating a second embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 there is illustrated an automatic washer generally at 10 embodying the principles of the present invention.
The washer has an outer cabinet 12 which encloses an imperforate wash tub 14 for receiving a supply of wash liquid. Concentrically mounted within the wash tub is a wash basket 16 for receiving a load of materials to be washed and a vertical axis agitator 18. A first motor 20 is provided which is drivingly connected to the agitator 18 to drive it in an oscillatory or rotary manner and is also selectively connectable to the basket 16 to rotatingly drive it. The assembly of tubs, agitator and motor is mounted by a suspension system 22 including springs and rods to a frame 24. A plurality of controls 26 are provided on a control console 28 for automatically operating the washer through a series of washing, rinsing and drying steps.
The drive mechanism is shown in greater detail in FIG. 2 where it is seen that the motor 20 is connected by means of a drive belt 30 and a gear arrangement such as a planetary gear assembly 32 to a vertical shaft 34 connected to the agitator 18. The wash basket 16 is connected via a spin tube 36 to the gear arrangement 32, such as to an outer ring gear having an external hub surface 44, to provide the selective rotating drive to the basket.
The wash tub 14 has a discharge sump 38 which is connected to an input of a discharge pump 40 driven by means of a separate, second motor 42. This second motor 42 is energized at selected portions of the wash cycle when it is desired to empty wash liquid from the wash tub.
During most portions of the wash cycle it is desirable to prevent the basket 16 from rotating while in other portions of the wash cycle it is desirable to have the wash basket rotate. A basket brake 46 in the form of a band 48 surrounding the external hub surface 44 is provided wherein the band 48 has an inner surface 50 with a high friction material so as to provide adequate griping of the external hub surface 44 when the brake is engaged.
As best seen in FIG. 3, the band 48 has a first end 52 which is looped around or attached to a stationary post 54. A second end 56 is pivotably attached to a cam 58 which in turn is pivotably carried on the post 54 and is biased in a clockwise direction as seen in FIG. 3 by a spring 60 carried on the post. This biasing keeps a continuous tension on the band 48 thus keeping the band 48 in close engagement with the external hub surface 44 thereby effecting braking action between the band and the hub surface. In order to release the brake, the cam 58 must be rotated in a counterclockwise direction as viewed in FIG. 3. To provide such counterclockwise rotation of the cam, and thus to actuate the brake an actuator means in the form of a connecting strap 61 is secured at a first end 62 to the cam 58 and at a second end 64 to a displaceable stator portion of the second motor 42.
A first embodiment of such a motor is illustrated in greater detail in FIG. 4 where it is seen that a motor 42A has a central rotor 66 having a generally cylindrical shape rotatable about a central axis 67 and is closely surrounded by two separate curved arm portions 68, 70 of a stator. One of the arm portions 70 is displaceable within a housing 72 of the motor such that it can linearly slide perpendicularly away from the rotor 66 along a radial line from the axis 67. A spring 74 is schematically illustrated as applying a biasing force to the displaceable stator arm portion 70 to cause it to move into a displaced position shown in phantom. The strap 61 is schematically illustrated as also being connected to the displaceable stator arm portion 70. When the motor is placed in the arrangement as illustrated in FIG. 3, the schematically illustrated spring 74 of FIG. 4 is in fact the spring 60 which biases the cam 58 in the clockwise direction. This spring force is transmitted through the linkage means comprising the cam 58 and the strap 61.
When the motor 42A is energized, attractive magnetic forces cause the displaceable stator arm portion 70 to slide radially toward the rotor 66 until a forward end 76 of the stator portion abuts against a stop block 78. The attractive magnetic forces are sufficient to overcome the force of spring 60, thereby causing the cam 58 to rotate in a counterclockwise direction and thereby releasing the braking action of the brake band 48 on the external hub surface 44. Therefore, the displaceable stator arm portion 70 through an actuator represented by the strap 61 produces a force external of the motor 42 to overcome the force of spring 60.
It is desirable to drive the wash basket 16 in a rotating manner during portions of the wash cycle in which the wash water is pumped from the tub 14. Thus, when the pump 40 is driven by the second motor 42, it is desirable to release the basket brake. This will automatically occur when the second motor 42 is energized. In all other portions of the wash cycle it is desirable for the wash basket to be held stationary relative to the tub and, with the motor 42 deenergized, the spring 60 will bias the band 48 into a braking position.
An alternative embodiment of the invention is illustrated in FIG. 5 in which a motor 42B is provided with a pair of stator arm portions 80, 82 in which one of the stator arm portions 82 is pivotably displaceable away from a central rotor 84 perpendicular to an axis 85 of the rotor. Again, a spring 86 is schematically illustrated to bias the displaceable stator arm portion 82 to a position spaced away from the rotor 84 and the strap 61 is also illustrated as being attached to the displaceable stator portion. The spring 60 of FIG. 3 provides the biasing force illustrated schematically by the spring 86 in FIG. 5 through the linkage of the cam 58 and the strap 61.
As the motor 42B is energized, attractive magnetic forces will cause the displaceable stator arm portion 82 to pivot back through an arc to a position closely adjacent to the rotor 84 thereby pivoting the cam 58 in a counterclockwise direction to release the brake band 48.
It will be appreciated by those skilled in the art that movement of the stator can be used to activate or deactivate other mechanisms through a linkage means or an actuator in lieu of separate components to effect a cost savings.
As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceeding specification and description. It should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art. | An automatic washer is provided with a separate motor to drive the drain pump, the motor having a displaceable stator portion connected to the basket brake mechanism such that when the pump motor is energized the basket brake will be released. Such a construction obviates the need for a separate component such as a solenoid to deactivate the brake mechanism. The stator portion is displaceable perpendicularly to the rotor axis and can move either in a radial sliding manner or can be pivotally mounted so as to move through an arc relative to the rotor. | 3 |
This application is a continuation-in-part of application Ser. No. 07/170,132, filed March 14, 1988 now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a method of improving the carding process in a card or a roller card unit wherein the carding cylinder is rotated by an electric drive motor and wherein the card operates in a working phase which is between an acceleration (start-up) phase and a deceleration (braking) phase.
In a known method the working rpm of the carding cylinder is fixed for determined types of fiber. Upon changing the fiber type, for example, from cotton to chemical fibers or conversely, the working rpm is changed by changing the mechanical transmission ratio between the drive motor and. the carding cylinder. This is effected, for example, by replacing the belt pulleys of appropriate diameter. Such an adjusting operation involves significant labor and delay, and only predetermined rpm changes are possible, dependent upon the structural design (stages) of the step-up or step-down arrangements. It is a further disadvantage of the known; arrangements that upon the inertia run of the cylinder, for example, upon braking following an interruption in operation, a larger quantity of fiber will accumulate on the cylinder than in the normal operational phase. This causes irregularities which, during the restart, may lead to a rupture in the fiber web or sliver. Even if such a rupture does not take place, a certain length of the web or sliver has to be removed to eliminate the above-noted irregularities. This makes unfeasible an automatic restart (re-threading) of the material, and thus losses of material will occur. The known arrangement utilizes a non-regulated drive motor, that is, during the processing of the fiber material, no rpm variation of the carding cylinder is intended because of the large inertia thereof. As a result, at the intended cylinder rpm too many fiber neps may remain in the fiber material.
It has been proposed to provide a switching unit in the current supply circuit for the drive motor of the licker-in/cylinder drive. By means of the switching unit a start-up or brake regulator circuit equipped with an a.c. setter may be operatively connected to the circuit of the motor for the licker-in/cylinder drive. The regulator may be disconnected after the start-up or braking step. With such an arrangement it is possible only to effect at the carding cylinder a constant acceleration or deceleration of the start-up or braking processes. There results a two-stage drive in which after the acceleration there is effected a switchover to the line current drive; that is, during the start-up or braking process a purposeful setting of predetermined rpm's is not intended and during the normal operating phase (line current supply) a variation of the cylinder rpm is not feasible at all.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved method of the above-outlined type from which the discussed disadvantages are eliminated and which, in particular, achieves a simple and rapid adaptation of the working rpm of the carding cylinder when the type of fiber material is changed and further, which makes feasible a restart of the card without severing the fiber web or sliver and reduces the nep number in the fiber.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the carding machine has a main carding cylinder, an electromotor drivingly connected to the carding cylinder and a control device, including a memory, for controlling the rpm of the carding cylinder. The main carding cylinder has a starting phase during which the main carding cylinder is accelerated to a working rpm and a stopping phase during which the main carding cylinder is decelerated from a working rpm to standstill. The method of operating the carding machine includes the steps of storing in the memory material-specific sets of rpm values for the starting phase and sets of rpm values for the stopping phase; and controlling the rpm of the main carding cylinder in the starting and stopping phases by the control device in accordance with respective rpm values stored in the memory.
By virtue of the invention an improvement of the carding process may be achieved. Particularly there can be obtained a simple and rapid adaptation or setting of the cylinder rpm upon changing the fiber types, for example, when changing from cotton to chemical fibers. It is a further advantage of the invention that both the rpm increase and the rpm decrease of the carding cylinder are controlled in a predetermined manner As a result, during acceleration and deceleration a fiber deposition of the same thickness is obtained as during the normal operating phase so that a restart of the card (re-threading of the fiber) after an interruption may be achieved without severing the fiber web or sliver or without the loss of fiber material Further, advantageously, it is feasible to set a cylinder rpm purposefully and in a predetermined manner at which most of the neps are separated from the fiber material In this manner a stepless cylinder rpm regulation and control is possible Thus, predetermined rpm's may be rapidly set in a stepless manner.
The significant advantages of the invention maybe summarized as follows:
(1) There is achieved a definitely and purposefully controlled start-up (rpm acceleration) of the carding cylinder, whereby determined rpm dependencies with respect to other rotary rollers of the card, such as the feed roller, the doffer, and the like may be established. This circumstance is of particular advantage in connection with an automatic start (thread-in) of the fiber web and a start-up run without severing the fiber web after an interruption.
(2) There is achieved a defined and braked deceleration of the carding cylinder By virtue of the integrated braking possibility, a separate braking device may be dispensed with. Further, this possibility too, is of particular importance for a restart of the operation without severing the fiber web.
(3) There is achieved a material-specific working rpm which is coordinated with other drives in addition to the carding cylinder. In this manner, for each fiber material the optimal, quality-dependent rpm may be set and the card may be operated in a reproducible manner.
Further advantageous additional features of the invention are as follows:
The electromotor is a d.c. motor or, preferably a frequency-controlled, three-phase squirrel cage motor. The electromotor is constantly accelerated or decelerated. The drive motor of the carding cylinder is connected with an rpm-regulating device which can generate either a predetermined rpm increase sequence or an rpm decrease (braking) sequence of the carding cylinder. Preferably, the rpm-regulating device comprises a static frequency changer. The rpm-regulating device is coupled with a control device. The control device, for example, a microcomputer control system, applies rpm data to the regulating device as a function of the momentary requirements. The microcomputer of the control device may be a TMS model manufactured by Trutzschler GmbH & Co. KG, Monchengladbach, Federal Republic of Germany. The control device has a residual memory for predetermined, material-specific cylinder rpm's. In the residual memory, the determined optimal material-specific data are stored once, with respect to the required rpm increase or rpm decrease of the main cylinder. Such data may be recalled automatically according to requirements at any time practically without additional work input. The control device further is equipped with respective units for the manual and automatic setting for data input, coordination and correction. Expediently, the control unit is so designed that it can deliver, control and correct predetermined rpm's for all other drives.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic side elevational view and a block diagram of principal components of a carding machine for practicing the method according to the invention.
FIG. 2 is a block diagram showing additional control functions.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning to FIG. 1, there is schematically shown, in side elevation, a carding machine which may be, for example, an EXACTACARD DK 715 model, manufactured by Trutzschler GmbH & Co. KG. The card has a feed roller 1, a licker-in 2, a main carding cylinder 3, a doffer 4, a stripper roller 5, crushing rollers 6, 7, a web guiding element 8, a sliver trumpet 9, calender rollers 10, 11 and travelling flats 12. The arrows drawn into the roller components 1-7, 10 and 11 indicate the directions of rotation.
The carding cylinder 3 is connected with an electric drive motor constituted by an rpm-controlled electromotor 13 which is operatively connected with a control apparatus 14 for setting predetermined rpm's.
The control apparatus 14 comprises a microprocessor 15 which constitutes a central processing unit and which is coupled with memories 16 and 17 and with an interface 18. The control components 15-18 form together a microcomputer. The memory 16 stores the data which relate to the actual production program and which are applied by an operator via a keyboard 19.
According to the invention, the starting rpm acceleration from zero rpm to the working rpm and a stopping acceleration from the working rpm to a standstill of the carding cylinder 3 are tightly controlled throughout the acceleration or declaration phase by the apparatus 14 in accordance with values previously inputted and stored in the memory 16. Such a control is of particular significance, for example, during the restarting of the card to ensure that the fiber material momentarily situated on the carding cylinder does not tear away from the fiber mass upstream or downstream of the carding cylinder. The permissible safe tension to which the fiber material extending between the carding cylinder and an adjacent roller (for example, the doffer 4) can be exposed is material-specific and consequently, for various materials different sets of rpm values are stored in the memory 16 and called during operation of the card. Thus, for different materials, a different smooth curve representing rpm values against elapsed time may be obtained. Advantageously, the smooth curve has a progressively decreasing slope towards the working rpm in the starting (acceleration) phase and towards standstill (zero rpm) in the stopping (deceleration) phase.
According to a preferred embodiment, the rpm values for the carding cylinder 3 are first determined as a function of the rpm of the doffer 4 and then the value pairs, each containing a doffer rpm and a cylinder rpm are stored, for example, to generate a smooth desired deceleration of the carding cylinder 3. Thus, starting from a doffer rpm of 200, there may be associated therewith a cylinder rpm of 350 and, to generate the entire pair set, the doffer rpm is, until it reaches zero, reduced by one while the cylinder rpm is, at the same time, reduced by five to obtain the individual deceleration rpm's for the stopping phase for a predetermined fiber material. The rpm pairs of the set are then stored in the memory 16 by means of the keyboard 19. For the starting phase a set of associated doffer rpm's and carding cylinder rpm's are similarly obtained and stored in the memory 16.
According to another preferred embodiment, the individual rpm values of the carding cylinder 3 from zero to the working rpm (acceleration) or from the working rpm to stoppage (deceleration) may be stored in the form of a material-specific formula such as, for example, a deceleration formula of B=2A-C where A is the doffer rpm, B is the cylinder rpm and C is an appropriately selected constant rpm such as 50.
In the memory 17 there are stored the permanently pre-programmed data which are applicable in the process control for each production program. This concerns, among others, data which in determined operational conditions permit or suppress certain machine function, such as, for example, data which fix the permitted rpm range of the carding cylinder.
The microprocessor produces, on the one hand, all control signals required for the operation of the microcomputer and provides, on the other hand, controlled by the program in the PMEM-memory 17, all data transfers between the memories and the external circuits and devices coupled by means of the interface 18. Further, the microprocessor 15 carries out all required computations and decisions. The interface 18 which is in principle a buffer memory with input and output registers, reads into the microcomputer, upon commands therefrom, external information as inputting signals, that is, keyboard signals and signals representing the operational state of the carding machine. Further, the interface 18 applies information (commands) from the microcomputer as output signals to the external control logic circuits, display devices and the like. The external devices include a display device 20, by means of which the essential program data and, for example, also data concerning the production speed as well as other machine conditions may be indicated. Further transmitters generate signals characterizing machine conditions. Such signals, for example, indicate whether or not the carding cylinder 3 runs. Further, there is provided a production logic with coupled regulating motors for the material transport. The logic contains in automatic operation command signals from the microcomputer and controls the operation as a function of the production program.
As has been noted earlier, the production programs are inputted in the memory 16 by an inputting device such as a keyboard 19. Upon depressing a programming key, a code is produced which is read into the microprocessor 15 via the interface 18. The microprocessor 15 decides whether the code is a command for the storing, erasing or inserting of a signal or an information for the production program. In the first case, the corresponding command is performed. In case of a command signal to "store", the microprocessor 15 effects the transfer of the last-inputted data into the memory 16. In the second case, numbers or functions for further use are intermediately stored into the data memory 16.
With the carding cylinder 3 there is associated an electronic tachogenerator 21 which serves as a measuring value receiver and which is connected with a regulating device 22 situated between the control device 14 and the drive motor 13. As shown in FIG. 2, the electronic tachogenerator 21 is connected to an analog-digital converter 23 which, in turn, is connected with the electronic control apparatus (microcomputer) 14. The analog-digital converter 23 is controlled by the microcomputer 14 which receives signals from a desired value transmitter 24. The microcomputer 14 is connected to a first digital-analog power converter 25 which is controlled by the microprocessor and which is connected with the motor 26 for the feed roller 1 of the carding machine. Further, the microcomputer 14 is coupled to a second digital-analog power converter 28 which is connected with the motor 27 for the doffer 4. Also, the microcomputer 14 is connected to a third digital-analog power converter 29 which is connected with the electric drive motor 13 for the main carding cylinder 3.
In operation, the rpm's of the carding cylinder 3 are converted by the tachogenerator 21 into analog electric signals which are, in turn, converted by the analog-digital converter 23 into digital electric signals and which-constitute input signals for the microcomputer 14. From the input signals and the stored program data the microprocessor derives digital electric output signals which are, by the subsequent digital-analog power converter 29, reconverted into analog electric signals and are then applied to the electric drive motor 13 which operates the carding cylinder 3.
Reverting once again to FIG. 2, there are illustrated further elements for additional control and monitoring functions. Thus, to the analog-digital converter 23 there is connected a testing device. Further, to the analog-digital converter there is applied an analog signal derived from the fiber web thickness measuring device. The following further devices are electrically connected to the microcomputer: operating elements such as an on and off switch for the card and the like; monitoring organs which report disturbances of the system during the course of operation, a master computer for controlling a plurality of card or roller card units, a program module, by means of which variable data may be reprogrammed on one occasion or upon changes; a display device for indicating production and counter positions and a device with which signal lamps, fuses or valves may be directly controlled.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | A carding machine has a main carding cylinder, an electromotor drivingly connected to the carding cylinder and a control device, including a memory, for controlling the rpm of the carding cyliner. The main carding cylinder has a starting phase during which the main carding cylinder is accelerated to a working rpm and a stopping phase during which the main carding cylinder is decelerated from a working rpm to standstill. The method of operating the carding machine includes the steps of storing in the memory material-specific sets of rpm values for the starting phase and sets of rpm values for the stopping phase; and controlling the rpm of the main carding cylinder in the starting and stopping phases by the control device in accordance with respective rpm values stored in the memory. | 3 |
BACKGROUND OF THE INVENTION
Painful fibromuscular disorders are common causes of pain and disability. In particular, fibrositis (also known as fibromyalgia) is a type of fibromuscular disorder that is a frequent cause of debilitating pain arising within muscles or muscle-tendon and tendon-bone junctions. Fibrositis is seen more frequently in women and is characterized by four constant features: pain, stiffness, fatigue and non-restorative sleep. In contrast with most rheumatic disorders, fibrositis rarely is responsive to corticosteroids and non-steroidal anti-inflammatory drugs. The only area in which medications are currently of proven value is in management of the associated sleep disorder.
I have discovered that tricyclic anti-depressants, usually prescribed orally for relief of mental depression or applied topically to the skin to relieve itching in dermatitis as described in my prior U.S. Pat. No. 4,395,420, are surprisingly effective at relieving or moderating the pain, stiffless, fatigue and sleep disorder associated with fibromuscular disorders such as fibrositis when applied topically. These compounds include the pharmaceutically acceptable salts of the tricyclics. The term pharmaceutically acceptable salts, as used herein, refers to the physiologically acceptable acid addition salts such as the hydrochloride, hydrobromide, hydroiodide, acetate, valerate, oleate, etc. Doxepin, amitriptyline and imipramine respectively are the tertiary amine derivatives of dibenzoxepin, dibenzoycloheptadiene and dibenzazepine wherein the nitrogen atom is connected to the ring structure by a three carbon aliphatic chain and the tertiary amine has two carbon atoms attached thereto in addition to the aliphatic chain.
The present invention relates to a method for topically treating fibromuscular disorders such as fibrositis. The principal object of the present invention is to apply topically divided doses of tricyclic anti-depressant compounds traditionally employed systematically for treatment of mental depression to relieve pain, stiffness, fatigue and sleep disorders characteristic of fibrositis. It is speculated that alleviation of the associated sleep disorder may arise either from relief of the pain and stiffness that prevented restful sleep, and/or from the sedative effect that these compounds are known to provide when administered systemically.
This and other objects of the present invention may be more readily understood when considered in conjunction with the following detailed description and examples.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
I investigated the possible therapeutic effects of topically applied formulations of tricyclic anti-depressant compounds in fibrositis by having patients suffering from fibrositis apply doxepin hydrochloride to localized areas of pain and/or stiffness. Patients noted not orgy relief of pain and stiffness as a consequent of such method of treatment, but also reported less fatigue and difficulty sleeping.
In the practice of the invention, concentrations of salts of doxepin, amitriptyline and impramine varying from about 1% by weight to about 10% by weight will be incorporated into creams, ointments, lotions and solutions and applied to patients suffering from fibromuscular disorders in divided doses for the relief of the pain, stiffness, and/or fatigue associated with such disorders. The preferred amount of active ingredients will be from about 1% to about 5% by weight of the carrier.
The following examples further illustrate the invention. In these examples, all percentages are by weight of the carrier.
EXAMPLE 1
A cream containing 5% of the commonly administered tricyclic antidepressant compound doxepin hydrochloride was topically applied to the lower neck, shoulders and back of a 53 year old female with pain and stiffness in these areas, as well as accompanying non-restorative sleep and fatigue. Within several days of twice daily application of this cream the patient was experiencing substantially less pain and stiffness in the neck, shoulders and back and was better rested upon awakening in the morning and less fatigued during the day.
EXAMPLE 2
A cream containing 1% doxepin hydrochloride was applied once daily for two weeks to the lower legs of a 55 year old male with pain and stiffness in the medial knee and upper Achilles tendon area of the feet. The patient experienced considerably less pain and stiffness in his legs and feet, was able to obtain more restful sleep at night, and was less fatigued during the day.
EXAMPLE 3
A 54 year old woman with diffuse pain and stiffness unresponsive to non-steroidal anti-inflammatory drugs (NSAIDS) applied a 5% cream containing doxepin hydrochloride several times daily to her neck, shoulders, and arms She related that she received almost immediate relief from pain and stiffness following each application of the doxepin cream and felt she was able to function considerably better during the day than when on NSAIDS.
It will be apparent to those skilled in the art that only the preferred embodiments have been described by way of example and that there are various modifications that fall within the scope of this invention. | A method for treating painful fibromuscular disorders comprising topical application to the skin of a therapeutically effective amount of a tricyclic antidepressant compound in a pharmaceutically acceptable vehicle. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a device for preventing a wheel from slipping off a spindle on which it is mounted in a freely rotatable manner, particularly but not exclusively intended for roller skates and the like.
In connection with roller skates and the like, for example, a basic requirement is that the wheels be prevented from slipping off their respective spindles, and this has been conventionally accomplished through the use of cotter pins, retainer rings, and the like arrangements effective to provide a suitable wheel retainer.
Such prior arrangements, while performing successfully as wheel retainers, have the disadvantage that they cannot be readily removed from a spindle on which they have been installed unless a specific tool in the hands of a skilled person is available. Accordingly, their use can make removal of a roller skate wheels, for instance, either for replacement or just maintenance purposes, a somewhat laborious operation, and above all, makes subsequent installation of the wheels problematic because such arrangements are liable to distort and become unusable if handled improperly.
The use of nuts threaded over a correspondingly threaded end portion of the spindle involves the availability of a suitable tool for their manipulation, and in addition, nuts may work loose in operation of the roller skates, or grow tighter on the spindles and freeze the wheels thereto, thus creating problems of a well-recognized seriousness.
To obviate such drawbacks, it has been recently proposed of using a retainer cap which is fitted over the free end of the spindle and has its sidewall surface formed with two or more longitudinal slots defining strips which can be spread elastically apart. A pair of diametrically opposed such strips are formed with respective teeth on the inside which are adapted to engage in corresponding notches provided at diametrically opposed locations on the end portion of the spindle. On fitting the retainer cap over the spindle end, engagement is achieved by a snap action. To remove such a retainer cap from the spindle, it is sufficient that the cap be moved angularly through a few degrees, such that the teeth are freed from their respective notches and made to ride on the solid spindle surface to spread the cap side strips elastically apart.
This prior retainer arrangement has the inherent advantage of being quick and practical to use both at its installation stage on the spindle and removal stage therefrom to replace a wheel, for example. However, it has the non-indifferent drawback that it cannot ensure a constant and effective retaining action for the wheel. In fact, in operation of the roller skates, by reason of the substantial physical contact between the cap and the wheel, it frequently happens that they freeze together, e.g. as a consequence of dust, mud, sand, and the like getting in between the cap and the wheel, which results in the cap being dragged around and disengaged from the spindle notches. When such disengagement occurs, the wheel is let free to slip off.
Another drawback originates from the retainer cap being liable to plastic deformation, especially at the spreadable longitudinal strips thereof, such that the strips can no longer perform their function of elastic engagement in the spindle notches.
SUMMARY OF THE INVENTION
It is a primary object of this invention to provide a retainer device as indicated, which has such structural and performance characteristics as to overcome all of the above-noted drawbacks with which the prior art is beset.
This and other objects to become apparent from the ensuing description, are achieved by a device for preventing a wheel from slipping off a spindle on which it is mounted in a freely rotatable manner, said spindle having an end portion formed with an annular groove in the vicinity of the spindle free end, characterized in that it comprises:
a body wherein a cavity is defined for access from outside the body through a circular entrance to receive said spindle end portion thereinto;
at least two co-planar, juxtaposed retainer plates fitting for sliding movement in guides formed on said body and extending in a radial direction to said entrance, said plates being movable in said cavity from a working position where they lie close together to engage in said annular groove to a rest position where they are held apart to disengage from said groove; and
a spreader member operable substantially as a pushbutton to drive, against the bias of a spring means, said retainer plates to the rest position, which spreader member is carried slidably in said body and movable in an axial direction relatively to the entrance of said cavity.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of a device according to the invention will be more clearly understood by having reference to the following detailed description of an embodiment thereof, to be taken by way of illustration and not of limitation in conjunction with the accompanying drawings, where:
FIG. 1 is an exploded perspective view of a roller skate wheel, its respective spindle intended to accommodate the wheel rotatably thereon, and a device according to the invention;
FIGS. 2 and 3 are sectional views of the same device as in FIG. 1, shown under two different conditions of use thereof;
FIG. 4 is an exploded perspective view of the same device as shown in the preceding figures; and
FIG. 5 is an enlarged scale perspective view of a detail of the device shown in FIG. 4.
DETAILED DESCRIPTION OF THE INVENTION
With reference to the drawing views, the numeral 1 generally designates a device according to the invention for preventing a wheel 2 from slipping off a spindle 3 on which it is mounted in a freely rotatable manner, said spindle 3 having an end portion 4 formed with an annular groove 5 located at a predetermined distance from the bevelled free end 6 of said spindle.
The device 1 of this invention comprises a body 7, essentially configured as a flattened cylindrical button, in which a cavity 8 is defined which is accessible from outside said body 7 through a circular entrance 9, formed centrally through a flat face 10 of said body 7. The cavity 8 is suitably dimensioned to accommodate the end portion 4 of the spindle 3 over which the inventive device 1 is adapted to fit in a manner to be explained.
At said flat face 10, there are formed in the body 7 two juxtaposed guides 11, 12 which extend radially to the circular entrance 9. Two retainer plates 13 and 14 are mounted slidably in these guides 11 and 12, respectively, which when positioned in said guides will lie co-planar with and juxtaposed to each other. The mutually confronting sides of said retainer plates 13, 14 are conventionally provided with respective semicircular cutouts 13a, 14a having substantially the same diameter dimension as the groove 5 on the end portion 4 of the spindle 3.
The retainer plates 13 and 14 are movable from a working position (FIG. 2), where they lie close together to engage the above-noted groove 5 in a manner to be explained, to a rest position (FIG. 3), where they are held apart to disengage from said annular groove.
In a preferred embodiment, each of said retainer plates 13, 14 constitutes a leg of a substantially U-shaped member 15, 16, the other leg 17, 18 whereof fits slidably in respective guides 19, 20 formed in the body 7 of said device 1 and extending parallel to the slideways 11, 12 for the retainer plates 13, 14 being discussed.
The cavity 8 in said body 7 is accessible from outside the body through a hole 21 formed axially through said body and open on the remote face 22 thereof from that formed with said circular entrance 9. The hole 21 is defined by two successive sections 21a, 21b having different diameters, between which an annular shoulder 22 is formed.
The hole 21 accommodates a cylindrical pushbutton 23 in a guided slidable fashion therein which has its end 24 adjacent to the inside of the cavity 8 conical in shape. This conical end 24 is adapted to engage with bevels 17a, 18a provided on the free opposed sides of the above-noted legs 17 and 18.
The pushbutton 23 has, at an intermediate location thereon, an annular rim 25 whose outside diameter is substantially equal to the inside diameter of the annular shoulder 22 against which it is intended to abut.
A spring ring 26 engages with the exteriors of the U-shaped members 15, 16 and fits into an annular groove 27 formed in the body 7 at an intermediate location to the guide pairs 11, 12 and 19, 20.
Under a rest or non-operative condition of the device according to the invention, the U-shaped members 15, 16 thereof would lie close together and held in these positions by the spring ring 26.
To have the device 1 perform its function of preventing the wheel 3 from slipping off, it is fitted over the end portion 4 of the spindle 5, the movement being advantageously facilitated by the bevelled free end 6 of the latter. In fact, as the retainer plates 13, 14, and hence the U-shaped members 15, 16, are pushed against the bevel on this free end 6, they are concurrently spread open against the bias of the spring 25 which, immediately thereafter, will cause the retainer plates to snap into the annular groove 5 and become engaged.
In this position, the wheel 3 is prevented from slipping off the spindle 4, and this retaining action can only be removed deliberately.
To release, it will be merely necessary to push in the pushbutton 23, thereby the conical end 24 of the latter engages with the ramp-like bevels 17a, 18a on the U-shaped members 16, 16 forcing them apart.
As a result of the above operation, the retainer plates 13, 14 will be concurrently moved away from each other, out of their working engagement in the groove 5 to their rest positions where they are disengaged from said groove. By suitably dimensioning the depth of the chamber 8 and "stroke" length of the pushbutton 23 inside said chamber--thereby on depressing the pushbutton, the tip of its conical portion 4 contacts the spindle free end 6--the same operation whereby the retainer plates 13, 14 are spread apart also causes the device to slide off said spindle.
Advantageously, the cylindrical button-like body of the device according to the invention should be sized and shaped to practically constitute a hub cover for the wheel 6, where this is of the type shown in FIG. 1.
The invention disclosed herein above is susceptible to many alterations and modifications within the invention scope. Thus, as an example, the device could comprise three retainer plates, arranged co-planarly at 120° from each other, or even four or more such plates, subject to their being arranged to symmetrically encircle the annular groove in which they are to be engaged. | A retainer device is disclosed wherein two retainer plates engage from opposed sides an annular groove formed in an end section of a spindle on which a wheel, specifically a roller skate wheel, is mounted in a freely rotatable manner. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a formwork panel for use in the casting of concrete stuctures and consisting essentially of a metal frame with longitudinal and transverse members to which a facing panel is secured to provide a casting surface, in use.
2. Description of the Prior Art
Hitherto, panels of this kind have been formed by welding together the frame members and securing the facing panels in position by welding or otherwise fastening them to the frame members, the sizes of the panels varying widely according to the requirements of use. Larger size versions of such panels can be inconvenient to handle on site and can also be difficult to store and transport. They also suffer from the disadvantage that damage to a relatively small part of a panel can lead to scrapping of the entire panel and because of the nature of the work in which such panels are used, this can be very inconvenient and give rise to considerable expense.
When very large areas of framework are required, composite panels are formed by connecting together numbers of individual panels. Because of the large variety of sizes and shapes of composite panels required on building sites, it has hitherto been necessary, in order to achieve the required degree of on site flexibility, to stock a large range of shapes and sizes of individual panels, with consequent inconvenience and expense.
BRIEF SUMMARY OF THE INVENTION
An object of the present invention is to provide a formwork panel of the aforesaid kind which minimises or avoids the drawbacks referred to.
According to the invention, a formwork panel comprises a plurality of longitudinal metal frame members and a plurality of transverse metal frame members adapted for interconnection in releasable manner to form a framework, and a facing panel secured to the framework in releasable manner to provide a casting surface, in use.
In one convenient arrangement, the longitudinal members are provided with recesses at lengthwise intervals to receive end portions of the transverse members, at least some of the transverse members being positively secured to the longitudinal members by retention means, such as screws. When retention means are not provided for all of the transverse members, the remainder thereof are retained in position by co-operation with respective ones of said recesses.
The transverse members may be of suitable shape, typically of angle or channel form, to embrace infill members, normally of timber, which permit facing panels to be secured to the framework by fixing members such as nails or screws driven into the infill members. Alternatively, the transverse members may be of closed hollow section and the facing panels secured directly to the metal sides thereof, as by screws for example.
Each panel may conveniently be adapted to co-operate with connectors for interconnecting a plurality of assembled panels to form larger composite panels. In one form of such composite panel, each such connector may conveniently include an elongate connecting element for spanning between frame members of adjacent panels, and pin and wedge devices arranged to act between said connecting element and respective ones of said frame members.
In another form of such composite panel, each connector may conveniently include an elongate connecting element for spanning between frame members of adjacent panels, and clamp devices arranged to act between said connecting element and respective ones of said frame members, each of which latter is provided with wedge surfaces for co-operation respectively with corresponding surfaces on the clamp members to hold said element tightly in engagement with the adjacent frame members.
From another aspect, the invention includes a kit of parts comprising a plurality of longitudinal metal frame members, a plurality of transverse metal frame members, and means operable to connect the transverse members to the longitudinal members to form a framework to which a facing panel may be secured, in use.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described, by way of example, with reference to the accompanying drawings wherein:
FIG. 1 is a plan view showing the framework forming part of the formwork panel of the invention;
FIG. 2 is a right side elevational and partly cross-sectional view, taken along line II--II of FIG. 1, on an enlarged scale, of part of the formwork panel of FIG. 1;
FIG. 3 is a fragmentary cross-sectional view, on an enlarged scale of part of the framework of FIG. 1;
FIGS. 4A, 4B and 4C are respective plan views of composite panels constructed from panels similar to that in FIG. 1;
FIG. 5 is an exploded view, of part of the panel of FIG. 1, showing connector devices for connecting separate parts to form a panel and for connecting together separate panels to form a composite panel;
FIG. 6 is a fragmentary cross-sectional view of part of FIG. 5 in assembled condition;
FIG. 7 is a view similar to FIG. 5 showing parts of an alternative form of connector for connecting together separate panels to form a composite panel; and
FIG. 8 is a fragmentary cross-sectional view of the clamping part of FIG. 7 in its assembled condition.
DETAILED DESCRIPTION
Referring to FIGS. 1 to 3, these illustrate a framework for use as the basis of a formwork panel of the invention including a pair of longitudinal side members 1, 2, between which extend at spaced intervals transverse members 3 which are releasably secured to the side members by bolts 4, for example. As will be seen more clearly from FIGS. 2 and 3, at least some of the transverse members 3 are channel-shaped and house timber battens 5 between the opposed sides 3A thereof, the battens conveniently being fixed in position by nails 5', screws 5", or spring dowel pins 5'", or a combination of some or all of these means. The outer surface 5A of each batten is preferably substantially flush with the outer surface of an adjacent longitudinal member 2 and a facing panel 5B would normally be secured to the battens 5 (FIG. 2) conveniently by nailing or similar means 5C, to provide a casting surface.
Each longitudinal member 1, 2 is also generally channel-shaped and the transverse members 3 are received within the open end of the channel. The longitudinal members 1, 2 are provided at the required intervals with fixing recesses 6 formed by U-shaped elements 7 welded to the sides of the longitudinal members 1, 2 with their open ends facing away from the base 2C of the longitudinal member 1, 2. Each of the transverse members 3 is provided with a generally U-shaped fixing element 8 of which the arms 8A, 8B are inserted between the sides 3A, 3B of the transverse element 3 and secured therein, as by welding. It will be seen that the transverse elements 3 may be readily releasably secured to the longitudinal elements 1, 2 by inserting the fixing elements 8 within the U-shaped elements 7 of the longitudinal elements, the securing being conveniently effected by means of the bolts 4 engaging nuts 9 secured within the fixing elements 8.
FIGS. 4A to 4C illustrate, respectively, three examples of how a plurality of panels X, Y, Z, may be joined together to form a larger composite panel. In one arrangement (FIG. 4A) this is accomplished by placing the panels X and Y side-by-side with their longitudinal members 1, 2 juxtaposed as shown, placing fixing bars 10 across the adjoining panels in alignment with the transverse members thereof and securing the bars in position on said transverse members to produce the composite panel. In another arrangement (FIG. 4B), a pair of panels X, Y, are placed side-by-side with their end transverse members 3 juxtaposed, fixing bars 10 then being placed at right angles across the junction between the adjoining panels and secured in position. In a third example, (FIG. 4C) a pair of panels X, Y are joined in the manner of FIG. 4A and a third panel Z, having a length equal to twice the width of a panel X, Y is placed along one side of the composite X, Y, panel and secured in position by one or more fixing bars 10 placed at right angles to bridge the junction between the X, Y panel and panel Z. It will be understood that many other combinations of panels and fixing bars may be used according to particular requirements.
One means for securing adjoining panels in position is illustrated in more detail in FIGS. 5 and 6. Each fixing bar is typically in the form of a hollow tube 10 of generally rectangular cross-section, the tube having aligned holes 10B respectively in opposed sides thereof and a pin 11 extending through the holes and secured in position, in this embodiment, by welding a head 11A of the pin against a side of the tube with which it is brought into engagement. The pin may alternatively be used without being secured to the fixing bar. A portion 11B of the pin projects from a side 12 of the tube and is provided with a generally diametrical slot 13 therethrough to receive a fixing wedge 14 in the manner to be described. Each transverse member 3 is provided with a window 15 to permit access to the slot 13 for the wedge. Thus, with a fixing bar 10 arranged in position in the manner illustrated in FIG. 6, with the slot 13 opposite to the window 15, the wedge 14 may be driven home to the position indicated in which one side of the wedge engages an edge portion of the slot 15 and the other side of the wedge engages an opposed inside wall of the slot 13. Each fixing bar is provided with at least two projections 11B and several can be provided according to the length of the fixing bar and the degree of security required. Facing panels 5B may then be secured to the battens 5, as before to complete the composite panel for use in a casting operation.
FIGS. 7 and 8 illustrate an alternative arrangement for securing adjoining panels in position. Each fixing bar is again in the form of a hollow tube 10A, this time of circular cross-section. The bar 3 is provided with ribs 20, formed in this instance by plates secured, respectively as by welding, to the upper and lower surfaces of the member 3 and disposed at an angle to the longitudinal axis of the member 3 to provide at their edges 20A wedge surfaces for the purpose to be described. A generally U-shaped clamp member 21 is provided, being shaped at its base to receive the tube 10A closely therein and having a pair of arms 22, 23 of sufficient length to permit them to engage behind the axially inner ends of the ribs 20 with the tube disposed between the base of the clamp member and the lateral wall of the member 3, as illustrated in FIG. 8. The ribs 20 may alternatively be formed integrally with the members 3 by pressing for example, or may be replaced by indents providing internal wedge surfaces for engagement by projecting portions of the clamp members.
Each arm of the clamp is formed on its inner surface with a pair of mutually oppositely inclined wedge surfaces 24, 25, one of which will co-operate with the wedge surface 20A of the adjacent rib 20 when the components are assembled. This twin surface arrangement enables the clamp to be used with either of its arms uppermost, as will become apparent hereafter. The angles of the surfaces 24, 25 are chosen so that the operative ones of these surfaces, depending upon the disposition of the clamp, form approximately the same angle with the longitudinal direction of the member 3 as the surfaces 20A of the ribs 20.
In order to secure the tube 10A to the bar 3, the clamp member 23 is engaged around the tube and, with the tube engaged against the member 3, as seen in FIG. 7, the arms 22, 23 of the clamp member can be engaged behind the wedge surface 20A of the ribs 20 and the clamp member driven home so that, in the case illustrated, the surfaces 25 of the arms come into tight wedging engagement with the rib surfaces 20A, effectively clamping the tube 10A to the member 3. The same action can be effected with the clamp turned through 180° about an axis at right angles to the tube 10A, which means that the orientation of the clamp does not have to be chosen carefully by site workers and its use is thereby facilitated.
The transverse members 3 may be provided, as shown, with pairs of slots 26 spaced to receive the hooked arms of a standard twin-armed formwork clamp 27, illustrated in FIG. 7 by which means tubular connecting members such as 10 or 10A may be secured along the backs of a plurality of panels to connect the panels together to form composite panels. This arrangement is particularly convenient for fixing panels in the end-to-end configuration of FIG. 4B. The position for the clamp has been chosen for the purpose of illustration only and the clamp would be located, in use, at any convenient position according to the desired run of the tubular connecting members.
The means for fixing the transverse members 3 to the longitudinal members 2 may be varied as desired, as may be the means for securing panels together to form composite panels. It will be seen that, since the panel of the invention may be readily completely dismantled, not only may it be more readily transported, packed, cleaned and stored, but in the event that any part thereof becomes damaged, this may be readily replaced without the necessity for replacing the entire panel, as would be required with many conventional panels. The facing panel, which may be of metal or timber, may be readily fitted on at a building site and this again can be easily replaced should damage occur. By providing longitudinal and transverse members of differing lengths, the sizes of individual panels may readily be varied, providing flexibility in the shapes and sizes of composite panels which may be formed, with the number of components reduced to a minimum.
It is conventional practice to secure soldiers 30 to formwork panels or panel assemblies to provide additional rigidity. These would extend longitudinally and normally be secured in conventional manner to the opposed faces of the transverse members 3 by hook bolts engaged in holes in said members and co-operating with clamp plates attached to the soldier. In the composite versions of the panel of the invention, soldiers may be attached to the connecting bars 10, such attachment being facilitated by providing the connecting bars with lateral flanges against which clamps may be engaged to secure the soldiers in position. Typical soldier dispositions are illustrated diagrammatically in broken lines in FIG. 4A. | A formwork panel is formed from metal longitudinal members and metal transverse members interconnected by devices such as screws to form a dismountable formwork panel. The panels may be interconnected by other connector devices to form larger composite panels of various sizes and shapes. The panels may be formed from a kit of parts for easy assembly and disassembly at a construction site. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. §119 to European Application No. 03103996.9 filed in Europe on 28 Oct. 2003, the entire contents of which are hereby incorporated by reference in their entirety.
BACKGROUND
The invention relates to a thermoanalytical sensor with a substrate that can carry a heat flow between a heat source thermally coupled to the substrate and at least one measurement position formed on the sensor, and further with a thermocouple arrangement formed on a substantially planar surface of the substrate to deliver a thermoelectric signal. Also included in the scope of the invention is a method of producing a sensor of this kind.
Thermoanalytical sensors of this kind are used to measure physical and/or chemical properties of a substance, a substance mixture, and/or a mixture undergoing a reaction, where the measurements are performed as a function of temperature or time and where the sample that is being measured is subjected to a controlled temperature program. Other known examples are the differential heat flow calorimetry and the differential power compensation calorimetry. In both of these applications, the analysis of a sample is performed in relation to a reference sample. The sensors being used in these cases therefore have two measurement positions, i.e., one position to perform the measurements on the sample and the other position to perform the measurements on the reference sample. In the first of the aforesaid applications, the thermoelectric signal delivered by the thermocouple arrangement represents a measure for the difference between the heat flow to the sample and the heat flow to the reference sample. In the second-named application, the thermoelectric signal delivered by the thermocouple arrangement is used to control the respective heat flow rates to the sample and the reference sample in such a manner that the temperature difference between the sample and the reference sample is regulated to zero.
The thermoanalytical sensors can be configured to have the highest possible degree of sensitivity covering, if possible, the entire temperature range of the analysis, i.e., a thermoelectric signal produced as a function of the heat flow is as strong as possible in terms of signal voltage. This can help to obtain a good signal-to-noise ratio. Therefore, as a way to satisfy this, state-of-the-art thermoanalytical sensors (DE 39 16 311 C2 and EP 0 990 893 A1) have a series of thermocouple junctions of the thermocouple arrangement joined in a circuit in such a manner that the thermoelectric signal is produced as the sum of the individual thermocouple voltages. The thermocouple junctions that form the thermocouple arrangement are laid out in a circular pattern around the center of the measurement position (or around the centers of the measurement positions, if there is more than one measurement position) spaced as closely as possible to each other in the azimuthal direction. Consequently, there is no space available that would allow a further increase in the number of thermocouple junctions in these state-of-the-art arrangements.
SUMMARY
Exemplary embodiments can solve the problem of achieving a further increase in sensitivity in a thermoanalytical sensor.
Under a first exemplary aspect of the invention, a solution is proposed for a thermoanalytical sensor with a substrate that can carry a heat flow between a heat source thermally coupled to the substrate and at least one measurement position formed on the sensor, and further with a thermocouple arrangement formed on a substantially planar surface of the substrate to deliver a thermoelectric signal, wherein the thermocouple arrangement includes a chain of thermocouple junctions which are composed of two different thermocouple materials and serially connected to form a thermocouple column. The chain of thermocouple junctions reaches in the azimuthal direction around the center of the measurement position, with the individual thermocouple junctions arranged at alternatingly different radial distances from the center of the measurement position. According to an exemplary embodiment, at least one of the interstitial surface portions that are azimuthally confined between a first thermocouple junction closest to the center and the two immediately neighboring second thermocouple junctions in the chain contains a third thermocouple junction and a fourth thermocouple junction that are direct neighbors to each other in the chain.
In the thermocouple column that is formed by this serially connected chain of thermocouple junctions, any two thermocouple junctions that are direct neighbors in the chain have a radial distance from each other. Thus, when there is a heat flow either in the direction towards the center of the measurement position or away from the center of the measurement position, a temperature difference will occur between any two neighboring thermocouple junctions in the chain because of the thermal resistance of the sensor. The temperature difference, in turn, will give rise to thermo-voltages between neighboring thermocouple junctions in the chain which, because of the serial chain arrangement, are added up as a voltage sum. Thus, the resultant overall thermoelectric signal represents the sum of the respective individual thermo-voltages that occur in each of the pairs of directly neighboring first and second thermocouple junctions as well as in the pairs of directly neighboring third and fourth thermocouple junctions. The pairs of thermocouple materials can be the same for all of the thermocouple junctions. One can also use a plurality of different pairs of thermocouple materials to form the thermocouples instead of only one pair of different materials. As each of the pairs of directly neighboring third and fourth thermocouple junctions is arranged in the free interstitial space confined azimuthally between one of the first thermocouple junctions and the two immediately neighboring second thermocouple junctions, the space available on the sensor surface is optimally utilized to increase the total number of thermocouple junctions. In this arrangement, the third thermocouple junctions can be arranged at a relatively close radial distance to the first thermocouple junctions, the latter being located at the shortest radial distance from the center of the measurement position, while the fourth thermocouple junctions can be arranged at a relatively close radial distance to the second thermocouple junctions. A crucible that serves to hold an analysis sample can be dimensioned so that in the measurement position, the bottom surface of the crucible covers the first and third thermocouple junctions, while the second and fourth thermocouple junctions remain uncovered since they lie on a larger radius from the center of the measurement position. With a crucible designed in this manner, the thermocouple arrangement can be particularly effective in measuring a radial temperature gradient that occurs in the vicinity of the crucible and corresponds to the heat flow exchanged between the heat source and the crucible.
A particularly advantageous embodiment of the invention can use a configuration where the first thermocouple junctions lie on a first circle whose midpoint is located at the center of the measurement position; the second thermocouple junctions lie on a second circle concentric to and with a larger radius than the first circle; the third thermocouple junctions lie on a third circle concentric to the first circle and with a radius that is larger than the radius of the first circle but smaller than the radius of the second circle; and the fourth thermocouple junctions lie on a fourth circle concentric to the first circle with a larger radius than the third circle. This arrangement conforms to the provision of radial symmetry of the measurement position or positions (if the arrangement has more than one measurement position) relative to the center, and it also conforms to the customary radially symmetric shape of the sample crucibles that is compatible with the symmetry requirement. The circular bottom surfaces of the crucibles designed for use with this embodiment of the thermoanalytical sensor are dimensioned with a radius that is larger than the radius of the third circle but smaller than the radius of the second circle.
To come as close as possible to a perfect radial symmetry, it is further helpful that the thermocouples are arranged on their respective circles at equal angular intervals. To make the radial symmetry as complete as possible, it is likewise helpful that the thermocouple material between neighboring first and second thermocouple junctions in the chain extends in the shape of rectilinear strip sections and that the thermocouple material between third and fourth thermocouple junctions that are immediate neighbors in the chain and lie within the same interstitial area likewise extends in the shape of rectilinear strip sections. The overall thermocouple arrangement in these cases has the appearance of a doubled-up star, i.e., two individual stars nested in each other and centered on the midpoint of the measurement position. With this design, the surface area is used very efficiently, allowing the arrangement of a particularly large number of thermocouple junctions and a commensurately high sensitivity of the sensor. As a further advantage, this arrangement is expandable by adding further nested stars as long as the inside circle of thermocouple junctions of the outermost star has a smaller radius than the outside circle of thermocouple junctions of the innermost star.
It further serves the purpose of achieving radial symmetry that the thermocouple material connecting each third thermocouple junction to that of its neighboring fourth junctions which lies in the next interstice of the star contains an azimuthally directed track portion. This azimuthal track portion can take the shape of a segment of a circle whose radius (from the midpoint of the measurement position) is slightly larger than the circle radius of the second thermocouple junctions that separate the interstices of the star from each other. In this arrangement, one end of the azimuthal portion can meet the end of a track portion consisting of the other of the two thermocouple materials to form the fourth thermocouple junction, while the other end of the azimuthal portion can continue into a radial portion extending to the third thermocouple junction in the neighboring interstice.
To connect the thermoanalytical sensors to a processing circuit, it is of practical advantage that connector terminals are formed on the surface of the substrate. These terminals are connected to the ends of the thermocouple column and serve to tap the thermoelectric sensor signal. They can be configured in the shape of flat connector pads or connector spots where connecting wires to a processing circuit can be attached.
In particular, it is envisaged within the scope of the invention that more than one of the measurement positions are arranged on the sensor. Specifically, one of the measurement positions can serve as reference position, while the other measurement positions serve to receive test samples. The reference position can either remain empty, or it can be occupied by an inert reference sample of known properties. If a differential calorimetry experiment is to be performed, the respective thermoelectric signals from the individual measurement positions can be combined through an appropriate circuit arrangement in such a manner that the respective differential signals between the reference position and each of the sample positions can be obtained directly.
An exemplary embodiment of the inventive sensor has two measurement positions arranged on one sensor unit. In this arrangement, one of the measurement positions can be used as reference position and the other as sample position. This configuration is analogous to arrangements used for differential heat flow calorimetry which will be familiar to those engaged in this field.
In an advantageous alternative embodiment of the invention, it is envisaged to arrange four of the measurement positions on one sensor unit in a configuration where a straight line between the centers of one pair of the positions perpendicularly bisects a straight line between the centers of the other pair, and vice versa. Thus, the centers of the four measurement positions lie at the corners of an imaginary square. This arrangement is advantageous in that it optimizes the thermal symmetry of all of the measurement positions.
The thermocouple arrangements in the sensors discussed up to this point serve to sense a heat flow between the measurement position and the heat source, or to sense a difference between heat flows associated with different measurement positions. In addition, in thermoanalytical applications it is considered advantageous to provide embodiments of the invention where a further thermocouple arrangement is formed at the measurement position on the surface of the substrate for the purpose of delivering a thermoelectric signal representing the absolute temperature at the measurement position, with separate connector terminals to tap the signal representing the absolute temperature. It is a known fact that thermocouples can only provide a direct measurement of temperature differences. If an absolute measurement is to be performed, the temperature at one of the measurement positions has to be known or held constant. According to the state of the art, the exposure of one of the measurement positions to the known temperature occurs outside of the sensor. The information that is thereby gained regarding the absolute temperature of a measurement position can be used for example to perform a mathematical correction of deviations from thermal symmetry in sensors with a plurality of measurement positions in cases where such deviations escape detection by a mere differential temperature measurement between the measurement positions and where the failure to detect the deviation would cause an error in the result of the analysis, because as a consequence of the asymmetry, the temperature difference does not precisely correlate to the difference between the heat flows at the different measurement positions.
In a practical design configuration, the thermocouple arrangement that serves to supply the thermoelectric signal representing the absolute temperature has an area containing a first thermocouple material that is arranged in a surface portion delimited by the thermocouple junctions which surround the measurement position, with a connector portion leading to one of the connector terminals that are arranged on the surface. In this configuration, the further thermocouple arrangement for the sensing of the absolute temperature is concentrated around the center of the measurement position and thus in direct thermal contact with the measurement position, i.e., with the sample that occupies the measurement position. As a practical measure to optimize the radial symmetry of the arrangement as much as possible, the delimited area of the first thermocouple material can, for example, be configured in the form of a circular ring.
In order to produce a thermoelectric signal representing the absolute temperature and to make it possible to tap the signal, a thermocouple junction with a second, different thermocouple material is arranged on the delimited portion of the first thermocouple material, with the second thermocouple material extending to one of the connector terminals formed on the surface.
An improvement in simplicity and a particularly efficient use of the available surface space on the sensor can be achieved through a design configuration where, for example, two of the measurement positions are formed on the sensor, with a connection between the second thermocouple materials of the two measurement positions being formed on the substrate and routed to a common terminal. The thermoelectric signals representing the absolute temperatures of the measurement positions are obtained by tapping the respective voltages between the common terminal and the two terminals that are connected to the first thermocouple material at the two measurement positions.
In a further practical embodiment which has a purpose of, for example, minimizing the pattern of connector terminals that have to be arranged on the substrate, two of the measurement positions are formed on the sensor and a connection is formed on the substrate between two electrically equivalent ends of the respective thermocouple columns associated with the measurement positions, while the other ends of the two thermocouple columns are connected to terminals that are formed on the substrate and serve to tap the difference between the respective thermoelectric signals of the two thermocouple columns. In this configuration, the two thermocouple columns are connected so that they oppose each other electrically, with the result that the thermoelectric signal occurring at the two terminals represents a difference of the temperatures at the two measurement positions.
For the evaluation of the results and the calculation of corrections, it can further be desirable to provide a possibility for tapping the respective output signals of the two thermocouple columns separately. Again in the interest of minimizing the structure of connector terminals required on the substrate, it is advantageous if the aforementioned connection between the two electrically equivalent ends of the thermocouple columns is also connected to a common terminal formed on the substrate. Thus, the respective output signal of each thermocouple column can be tapped separately between the common terminal and the terminal at the other end of the respective thermocouple column.
Within the scope of the invention, it is envisaged in particular that the thermocouple arrangements formed on the substrate are configured as thick film arrangements. The concept of using thick film technology to produce the thermocouple arrangements on the substrate is presented in the above-referenced German patent DE 39 16 311 C2 and the underlying German patent application publication DE 39 16 311 A1 with a discussion of the advantages that are achieved by using thick film technology. The disclosure of these two documents is hereby included by reference in the present disclosure. In particular, using thick film technology provides a simple solution to the problem of insulating the individual structural elements of the thermocouple arrangements against the outside, i.e., against sample crucibles or reference sample crucibles that are placed on the measurement positions.
To achieve the desired thermally inert behavior and durability of the sensor, it is advantageous if the substrate consists of or contains, a ceramic material.
Under a second exemplary aspect of the invention, a further solution is proposed for a thermoanalytical sensor with a substrate that can carry a heat flow between a heat source thermally coupled to the substrate and at least one measurement position formed on the sensor, and further with a thermocouple arrangement formed on a substantially planar surface of the substrate to deliver a thermoelectric signal, wherein the thermocouple arrangement includes a chain of serially connected thermocouple junctions which are composed of two different thermocouple materials. According to an exemplary embodiment, the thermocouple junctions are arranged in two or more planes that lie on top of each other, with each plane being insulated from the next plane by an insulating layer, each plane containing a section of the circuit arrangement, and each section being formed by conductor leads connecting the thermocouple junctions, where the overall circuit arrangement is formed by connecting the appropriate ends of the sections to each other by interlayer contacts.
According to the embodiment just outlined, the overall circuit arrangement is subdivided into at least two sections. As the thermocouple junctions that belong to the individual sections are arranged on top of each other, the available surface area on the sensor is multiplied in accordance with the number of planes that are layered on top of each other. Consequently, the circuit arrangement can contain a corresponding multiple of the number of thermocouple junctions. The result is a commensurate increase in the strength of the thermoelectric signal delivered by the circuit arrangement and in the sensitivity of the sensor.
As an advantageous way of realizing the foregoing features, terminals for tapping the thermoelectric signal of the thermocouple arrangement are formed in the top plane relative to the substrate, and one end of the circuit section that occupies the bottom plane is connected to one of the terminals through interlayer contact. The ability to tap the thermoelectric signal from the terminals lying in the top plane facilitates the installation and connection of the sensor in a thermoanalytical instrument.
In an advantageous embodiment, the thermocouple junctions within a section of the circuit arrangement are connected in series and the sections, in turn, are serially connected to form the circuit arrangement, so that the result is a thermocouple column.
With preference, the thermocouple junctions are arranged so that they proceed in the azimuthal direction around the center of the measurement position and lie at alternatingly different radial distances from the center.
In a further advantageous configuration, the sections of the circuit arrangement that lie in different planes are of a substantially congruent shape.
Under a third exemplary aspect of the invention, a further exemplary embodiment is proposed to provide in a thermoanalytical sensor with a substrate that can carry a heat flow between a heat source thermally coupled to the substrate and at least one measurement position formed on the sensor, and further with a thermocouple arrangement formed on a substantially planar surface of the substrate to deliver a thermoelectric signal, wherein the thermocouple arrangement includes a serial chain of thermocouple junctions associated with the measurement position, the junctions being composed of two different thermocouple materials and connected into a circuit arrangement, and wherein the substrate has a thermal conductivity that does not exceed 5 Watt per meter and per degree Kelvin.
A thermal conductivity of this reduced magnitude in comparison to the conventional aluminum oxide substrates has the effect that a stronger temperature gradient develops between the thermocouple junctions that are exposed to the different temperature levels. As a result, the thermoelectric signal produced by the thermocouple arrangement is commensurately increased and, consequently, the sensitivity and signal-to-noise ratio of the sensor are improved. However, as a cautionary remark, as the thermal conductivity of the substrate is decreased, the time constant of the sensor is increased. Even under the hypothetical assumption that materials technology imposes no limits on lowering the thermal conductivity, in an exemplary embodiment, a bottom limit that should not be traversed is represented by a level of thermal conductivity where the time constant of the substrate is still marginally adequate.
In this regard, the range of interest for practical applications includes materials with a thermal conductivity no lower than 0.5 W/(m×K).
Using a low thermal conductivity, a conductivity value of, for example, no more than 3 W/(m×K) is preferred, with an even higher level of preference for values not exceeding 2 W/(m×K). This leads to particularly noticeable improvements in comparison to conventional aluminum oxide substrates.
In a practical embodiment, a special ceramic material is selected for the substrate, with a lower conductivity value than the conventional ceramic oxide materials, but with favorable mechanical and electrical properties comparable to the oxide ceramics. To name an example, the substrate material that is available under the trade name PYTHAGORAS has been found suitable, having a thermal conductivity around 2 W/(m×K). Also suitable, albeit less desirable in regard to its mechanical properties, the glass ceramic substrate which is available under the product name MACOR has a thermal conductivity of significantly less than 2 W/(m×K).
A fourth exemplary aspect of the invention relates to a method of producing a thermoanalytical sensor wherein a design pattern of at least two different thermocouple material pastes is printed by way of a thick-film technique onto a substantially planar surface of a substrate. The thick-film pattern, which is fired after printing, represents a thermocouple arrangement with a serially connected chain of thermocouple junctions composed of two different thermocouple materials and associated with at least one measurement position, which serves to deliver a thermoelectric signal. An exemplary method is distinguished by the fact that the circuit pattern is divided into at least two partial patterns, that a first partial pattern is produced in thick-film technology on the substrate, an insulating layer with contact passage holes for the connection of the partial patterns is overlaid on the first partial pattern, a further partial pattern is produced on the insulating layer, and the foregoing procedure is repeated until all partial patterns are produced above one another.
By using thick-film technology, the structure of the partial patterns and insulating layers can be produced on the substrate at a relatively low cost. Conventional pastes can be used for the thermocouple materials, for example gold paste for one of the thermocouple materials and gold/palladium paste for the other thermocouple material. If desired, it is possible to use other materials in order to produce thermocouples with different properties. The pastes can be applied by a known procedure using screen-printing techniques in accordance with the prescribed patterns. Each application of a pattern is followed by a firing operation. In particular, one can first apply and fire one of the thermocouple materials for each partial pattern and subsequently apply and fire the other thermocouple material in accordance with the respective partial pattern. Performing the two firing operations separately has a favorable effect on the thermoelectric conductivity of the thermocouples that are formed in the manner just described.
In advantageous embodiments of the inventive method, the partial patterns are configured in such a way that the repetitive procedure of applying each partial pattern as a layer directly produces the thermoanalytical sensors with the preferred circuit configurations. In a first embodiment of this kind, the partial patterns are designed substantially congruent to each other. In a further embodiment, each partial pattern is serially connected to the next by only one connection, whereby the number of interlayer connections can be kept small. In a further embodiment, the topmost partial pattern relative to the substrate is overlaid with an insulating layer with connector terminals from which the thermoelectric signal can be tapped, wherein at least one of the connector terminals is joined through interlayer contact to the partial pattern in the bottom layer relative to the substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
In the description that follows below, exemplary embodiments of the invention are explained in more detail with references to the drawings, wherein:
FIG. 1 schematically represents a plan view of a thermoanalytical sensor according to a first exemplary embodiment of the invention arranged in the area of a measurement position;
FIG. 2 schematically represents a plan view of a thermoanalytical sensor according to a second exemplary embodiment of the invention with two measurement positions;
FIG. 3 represents an exploded view of a thermoanalytical sensor according to a third exemplary embodiment of the invention;
FIG. 4 schematically represents a plan view of a thermoanalytical sensor according to a fourth exemplary embodiment of the invention; and
FIG. 5 represents an exploded view of a thermoanalytical sensor according to a fifth exemplary embodiment of the invention.
DETAILED DESCRIPTION
A thermoanalytical sensor according to a first exemplary embodiment of the invention has a cylindrical substrate 1 , where the height of the cylinder is small in relation to its radius. FIG. 1 represents in schematic form a plan view of a top surface 2 of the substrate which has the shape of a circular disk, as seen in the direction of the cylinder axis of the substrate 1 . In the area delimited between the cylinder axis and the radially outer border of the surface 2 , a measurement position 3 is arranged which is equipped with a thermocouple arrangement that has been put in place through a thick-film technology procedure.
In this thermocouple arrangement, strip-shaped sections of two different thermocouple materials overlap at each of their adjoining ends, so that a series of thermocouple junctions is formed by these overlaps. The thermocouple junctions are arranged on four concentric circles whose common center point 4 represents the center of the measurement position 3 . The first thermocouple junctions, which are located on the first circle closest to the center are identified in FIG. 1 by the reference symbol 5 . Each of the first thermocouple junctions is composed of overlapping, short azimuthal end portions of the two different thermocouple materials 6 and 7 . From the azimuthal end portions, the thermocouple materials 6 and 7 extend narrowly spaced from each other and parallel to each other in a substantially outward radial direction relative to the center 4 to a second circle, where the second thermocouple junctions 8 are formed likewise by overlapping, short azimuthal end portions analogous to the first thermocouple junctions 5 .
The third thermocouple junctions 9 lie on the third circle, whose radius is larger than the radius of the first circle and smaller than the radius of the second circle. Similar to the first thermocouple junctions 5 , the third thermocouple junctions 9 have short azimuthal overlapping end portions of the two thermocouple materials 6 and 7 . From the third thermocouple junctions 9 , the thermocouple materials 6 and 7 extend substantially in the shape of strip sections in an outward radial direction to the fourth circle, whose radius is larger than the radius of the second circle. The ends of the strips of the thermocouple material 7 lie on the fourth circle where they meet and overlap with the ends of the thermocouple material 6 to form the fourth thermocouple junctions 10 . From the fourth thermocouple junctions 10 , the thermocouple material 6 extends in the azimuthal direction following the fourth circle. Each of the azimuthal strip sections 11 of the first thermocouple material 6 extends from a fourth thermocouple junction 10 to the substantially radial strip section of the thermocouple material 6 that originates from the azimuthally nearest neighboring third thermocouple junction 9 . The first, second, third and fourth thermocouple junctions 5 , 8 , 9 , and 10 , respectively, are arranged on their respective circles at equal azimuth-angle intervals from each other.
Deviating from a completely symmetric configuration of the first thermocouple junctions 5 , one first thermocouple junction 5 ′ is distinguished by the fact that the substantially radial strip section of the first thermocouple material 6 ′ which originates from the junction 5 ′ continues beyond the radius of the second circle to a terminal pad 12 that is formed on the surface 2 of the substrate 1 . This first thermocouple junction 5 ′ forms the end of a thermocouple column in which all thermocouple junctions 5 , 5 ′, 8 , 9 and 10 are connected in a serial sequence. The other end of the thermocouple column is formed by the fourth thermocouple junction 10 ′ serially following the third thermocouple junction 9 ′ that lies radially next to the aforementioned first thermocouple junction 5 ′. The strip section of thermocouple material 7 ′ which runs from the third thermocouple junction 9 ′ in a substantially outward radial direction is at its outer end on the fourth circle joined to a strip section of the thermocouple material 6 ″ to form the fourth thermocouple junction 10 ′. The strip section of the thermocouple material 6 ″ runs to a terminal pad 12 ′ that is formed on the surface 2 .
The drawing and the accompanying description given in the foregoing paragraphs also make it clear that the thermocouple materials 6 , 7 , 7 ′ are, in an exemplary embodiment, overlaid on each other only in the areas where they mutually overlap and thereby, i.e., through the contact provided by the overlap, form the thermocouple junctions 5 , 5 ′, 8 , 9 , 10 , 10 ′. All other parts of the thermocouple materials 6 , 7 , 7 ′ run side-by-side in one and the same plane.
In the serially connected sequence that forms the thermocouple column beginning at the first thermocouple junction 5 ′, each first thermocouple junction 5 or 5 ′ has a second thermocouple junction 8 as its immediate neighbor until the counterclockwise azimuthal loop about the center point 4 has reached the first thermocouple junction 5 ″ which, in the azimuthal direction, lies next to the starting thermocouple junction 5 ′ of the column. The junction 5 ″ is connected through the substantially radially directed strip section of the thermocouple material 7 to a further thermocouple junction 8 ′ which has a third thermocouple junction 9 ″ as its immediate neighbor in the serial sequence, followed by pairs of immediately neighboring fourth and third thermocouple junctions 10 and 9 , respectively, until the fourth thermocouple junction 10 ′ has been reached which forms the other end of the thermocouple column. The overall thermocouple arrangement has the appearance of a doubled-up star. The thermocouple materials 6 , 7 that extend in the shape of rectilinear strips between the first and second thermocouple junctions 5 and 8 form an inner star and delimit between each other azimuthal interstitial areas 13 . In each of the interstitial areas 13 lies a pair 9 , 10 of third and fourth thermocouple junctions that are immediate neighbors in the serial sequence. The third and fourth thermocouple junctions 9 , 10 with their connecting strip sections of thermocouple materials 6 , 7 form the outer star. The arrangement could be continued in analogous manner with a further azimuthal ambit in counterclockwise direction starting at the thermocouple junction 10 ′.
A thermoelectric sensor according to a second exemplary embodiment of the invention is shown in FIG. 2 , using an analogous form of representation as in FIG. 1 . In this embodiment there are two measurement positions 3 , 3 ′, each with a structure that is completely equivalent to the measurement position 3 as described above in the context of FIG. 1 . The reader is therefore referred to the description of FIG. 1 for the structural details of the second embodiment. The two measurement positions 3 and 3 ′ of the second embodiment are arranged at equal distances diametrically opposite to each other relative to the cylinder axis of the substrate 1 . The letter “S” for “Sample” is printed on the substrate surface 2 near the measurement position 3 , and the letter “R” for “Reference” is printed near the measurement position 3 ′. This indicates that a sample is to be placed on the measurement position 3 , and an inert reference sample is to be placed on the measurement position 3 ′.
The arrangement in FIG. 2 deviates from FIG. 1 only in that the fourth thermocouple junction 10 ′ at the end of the thermocouple column formed at the measurement position 3 and likewise the fourth thermocouple junction 10 ′ at the end of the thermocouple column formed at the measurement position 3 ′ are not each connected to a separate terminal pad 12 ′ in analogy to the terminal pad 12 ′ in FIG. 1 . Instead, these ends of the two thermocouple columns are joined by a strip section of the thermocouple material 6 . The first thermocouple junctions 5 ′ that form the other ends of the respective thermocouple columns at the measurement positions 3 and 3 ′ are each connected to a terminal pad 12 in the same manner as in FIG. 1 . Through this design configuration, the two thermocouple columns are arranged so that they electrically oppose each other in the circuit. Thus, by tapping the two terminal pads 12 in the second embodiment, one obtains the difference between the respective thermoelectric signals of the two thermocouple columns, while the first embodiment delivers between the terminal pads 12 , 12 ′ the entire thermoelectric signal produced by the thermocouple column that is formed on the measurement position 3 .
In the thermoanalytical sensor according to a third exemplary embodiment of the invention, the overall pattern formed by the thermocouple materials and thermocouple junctions of the thermocouple arrangement is subdivided into a plurality of partial patterns which are arranged on top of each other, with the appropriate electrical terminations of the partial patterns being connected to each other. This concept is illustrated in FIG. 3 , shown in an exploded view for the sake of clarity, wherein the individual strata of the layered arrangement are shown pulled apart from each other in the direction of the cylinder axis of the substrate 1 which is identical to the substrates shown in FIGS. 1 and 2 . The arrangement of FIG. 3 has a total of three partial patterns 14 , 15 and 16 , respectively, each of which is configured analogously to the pattern forming the thermocouple arrangement in the second embodiment which is represented in FIG. 2 . Minor deviations from the pattern shown in FIG. 2 exist only to the extent necessary for forming the connections of the electrical terminations of the partial patterns.
In FIG. 3 , the partial pattern 14 at the bottom is arranged on the surface 2 of the substrate in the same manner as in FIG. 2 . Likewise as in FIG. 2 , the thermocouple material from the first thermocouple junction 5 ′ that forms one end of the overall circuit arrangement represented by the entire pattern is connected to the terminal pad 12 . Also as in FIG. 2 , the part of the pattern shown on the left side is joined to the right-hand part by means of the connecting strip 6 of thermocouple material. However, in contrast to FIG. 2 , the analogous first thermocouple junction at the end of the right-hand part in FIG. 3 is connected to an interlayer contact pad 17 which is arranged at a distance from the left-hand terminal pad 12 in FIGS. 2 and 3 as well as from a second terminal pad 12 that corresponds to the right-hand terminal pad in FIG. 2 but is configured as an insular pad in FIG. 3 , i.e., non-contiguous with the rest of the partial pattern.
The partial pattern 14 that is arranged on the surface 2 is topped by an insulating layer 18 that is equipped with interlayer contact holes 19 at matching positions for the interlayer contact pad 17 and the two terminal pads 12 . On the surface 20 that faces away from the partial pattern 14 , the insulating layer 18 carries the partial pattern 15 . At the analogous position where the bottom-layer partial pattern 14 has an end connection to the terminal pad 12 , the middle-layer partial pattern 15 has an end connection to an interlayer contact pad 17 ′ which is connected to the interlayer contact pad 17 by way of the interlayer contact hole 19 that is congruent with the interlayer contact pads 17 and 17 ′. Where the bottom-layer partial pattern 14 has an end connection to the interlayer contact pad 17 , the right-hand part of the partial pattern 15 in FIG. 3 has an analogous end connection to an interlayer contact pad 21 which is electrically insulated against the bottom layer by the insulating layer 18 . The two terminal pads 12 of the bottom layer are brought out through the congruently positioned interlayer contact holes 19 to the surface 20 of the insulating layer 18 where they appear as insular pads.
The surface 20 of the insulating layer 18 which carries the partial pattern 15 is topped by an insulating layer 22 that is equipped with interlayer contact holes 19 ′ at matching positions for the interlayer contact pad 21 and the two terminal pads 12 . The surface 23 of the insulating layer 22 carries the partial pattern 16 , which forms the topmost partial pattern in FIG. 3 . The end connection of the left-hand part leads to an interlayer contact pad 17 ″ which is connected to the congruently positioned interlayer contact pad 17 ′ of the middle-layer partial pattern 15 by way of a likewise congruently positioned interlayer contact hole 19 ′ of the insulating layer 22 . The end connection of the right-hand part leads to the right-hand terminal pad 12 in FIG. 3 , which is contacted directly through all layers by way of congruently located interlayer contact holes 19 ′ and 19 of the insulating layers 22 and 18 , respectively. The left-hand terminal pad 12 connects through analogous interlayer contact holes 19 ′ and 19 to the left-hand terminal pad 12 of the bottom-layer partial pattern 14 in FIG. 3 .
On top of the surface 23 of the insulating layer 22 that carries the topmost partial pattern 16 there is an insulating layer 24 equipped only with interlayer contact holes 19 ″ that match the positions of the terminal pads 12 . The thermoelectric signal delivered by the entire circuit arrangement can be tapped at the terminal pads 12 that are contacted through the interlayer contact holes 19 ″. The signal represents the sum of the thermo-voltage differences delivered by the individual partial patterns 14 , 15 and 16 between the left-hand part and the right-hand part of each partial pattern.
Furthermore, in addition to the symbols “R” and “S” mentioned already in the context of FIG. 2 , the exposed surface 25 of the insulating layer 24 carries arc-shaped markings 26 to facilitate the centered positioning of the sample- and reference crucibles relative to the center points 4 and 4 ′ of the respective measurement positions (see FIG. 2 ).
The third embodiment shown in FIG. 3 can be produced in particular with the use of thick-film technology. The process starts by screen-printing and firing the partial pattern 14 with suitable thermocouple material pastes on the surface 2 of the substrate 1 . This operation preferably can be performed in two steps, the first of which consists of the application and immediate firing of only those structural components of the pattern that consist of a first thermocouple material. In the second step, the structural elements consisting of the other thermocouple material are printed and the firing is repeated. This two-step procedure has a favorable effect on the quality of the thermocouple junctions. After the insulating layer 18 has been put in place, the second partial pattern 15 is produced in the same manner, and the foregoing procedure is repeated until all insulating layers and partial patterns have been completed, at which point the topmost insulating layer 24 is put in place.
The thermoanalytical sensor according to a fourth exemplary embodiment of the invention is shown in FIG. 4 in a form of representation that is analogous to FIG. 1 . This fourth embodiment has a total of four measurement positions 30 , 31 , 32 and 33 , respectively, each of which has an analogous configuration to the measurement position 3 in FIG. 1 . In regard to the individual measurement position, the reader is therefore referred to the description of the embodiment shown in FIG. 1 . Particularly like in FIG. 1 , the end portions of the individual thermocouple columns are connected to a pair of terminal pads 12 , 12 ′ where the thermoelectric voltage can be tapped that is produced by the respective column. The centers of the four measurement positions 30 , 31 , 32 , 33 are located on the corners of a square whose diagonals intersect in the cylinder axis of the substrate 1 .
The thermoanalytical sensor according to a fifth embodiment of the invention is shown in FIG. 5 in an exploded view where the layers of the arrangement are pulled apart in the direction of the cylinder axis of the substrate 1 . In regard to the differential circuit arrangement that is formed between the two doubled-up star patterns by means of the connector 6 and the two terminal pads 12 , the fifth embodiment is completely analogous to the second embodiment which is described in the context of FIG. 2 . Insofar as the differential circuit arrangement is concerned, the reader is therefore referred to the description of FIG. 2 . However, FIG. 5 additionally shows an insulating layer 34 which is also present in the second embodiment but is not shown in FIG. 2 . The insulating layer 34 has windows 35 matching the locations of the terminal pads 12 of the thermocouple arrangement, so that the differential thermoelectric signal can be accessed at the windows 35 . The insulating layer 34 allows metallic crucibles to be placed on the measuring positions without thereby causing short circuits between the thermocouple junctions.
In addition to the features which have just been described and are already part of the second embodiment in accordance with FIG. 2 , the fifth embodiment has at each of the two measurement positions 3 , 3 ′ a further thermocouple arrangement 36 , 36 ′, respectively, on the exposed surface 37 of the insulating layer 34 . Each of these further thermocouple arrangements 36 , 36 ′ includes a ring-shaped first thermocouple material 38 , 38 ′ in a centered arrangement relative to the center 4 , 4 ′ of the respective measurement position 3 , 3 ′. In FIG. 5 , the two further thermocouple arrangements 36 , 36 ′ are, for the sake of clarity, drawn to a magnified scale in comparison to the lower parts of the exploded drawing. In actuality, the ring-shaped first thermocouple material 38 , 38 ′ is arranged within the respective first circle on which the first thermocouple junctions 5 are located. In the areas delimited, respectively, by the inside perimeters 39 , 39 ′ of the ring-shaped arrangements 38 , 38 ′, the insulating layer 34 and the substrate each have respective congruently located axial passage openings 40 , 40 ′ and 41 , 41 ′. Passage openings of this kind also exist in the other, previously described embodiments and are identified with corresponding reference symbols in the respective drawing figures.
Each of the ring-shaped first thermocouple materials 38 , 38 ′ has a strip-shaped radial extension leading, respectively, to the terminal pads 43 , 43 ′. Furthermore, there is a common terminal pad 44 arranged on the centerline that runs perpendicular to an imaginary connecting line between the respective center points 4 , 4 ′ of the measurement positions 3 , 3 ′. Originating from the common terminal pad 44 , a connecting lead 45 runs along the centerline between the two terminal pads 43 , 43 ′ to a Y-shaped juncture where the connecting lead 45 branches out into two strip-shaped arms 46 , 46 ′ which extend in mirror-symmetry relative to the centerline into the ring-shaped first thermocouple materials 38 and 38 ′, respectively. The terminal pad 44 , the connecting lead 45 and its arms 46 , 46 ′ consist of a second thermocouple material which forms thermocouple junctions at the connections to the first thermocouple materials 38 and 38 ′. The thermoelectric signals that occur at these two thermocouple junctions can be tapped between the common terminal pad 44 and the respective terminal pads 43 and 43 ′. The two thermoelectric signals correspond to the respective absolute temperatures at the measurement positions 3 and 3 ′. For the determination of the absolute temperature values, the signal is further processed in a known manner through an appropriate circuit arrangement.
In all embodiments of the foregoing description, the sensor is thermally coupled to a heat source through thermal contact between a border area of the substrate 1 and the heat source. This can be achieved, e.g., if a ring-shaped border area of the bottom side of the sensor, i.e., the reverse side of the top surface 2 , is seated on an appropriately shaped heat-conducting flange of the heat source. Specifically, the ring-shaped border area can be delimited on the outside by the radially outer border of the cylindrical disk that forms the substrate 1 and on the inside by a cutback in the shape of a flat cylinder whose radius is somewhat smaller than the radius of the substrate 1 .
The radial temperature gradients that occur relative to the center points 4 , 4 ′ of the measurement positions 3 , 3 ′, 30 , 31 , 32 , 33 are the reason for the thermoelectric voltages that are generated between the thermocouple junctions 5 and 8 as well as between the junctions 9 and 10 , which are radially distanced from each other. These temperature gradients increase with decreasing thermal conductivity of the substrate 1 . Therefore, in order to achieve a high sensitivity of the sensor, substrates with a relatively small thermal conductivity λ can be used, specifically with λ not exceeding 5 W/(m·K), preferably with λ not exceeding 3 W/(m·K) or even not exceeding 2 W/(m·K). Substrates 1 that have been found suitable are ceramics with special properties, for example made of the ceramic material that is available under the trade name PYTHAGORAS, or made of the glass-ceramic material that is available under the trade name MACOR, which has a λ-value of about 1.5 W/(m·K).
It will be appreciated by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restricted. The scope of the invention is indicated by the appended claims rather than the foregoing description and all changes that come within the meaning and range and equivalence thereof are intended to be embraced therein. | In a thermoanalytical sensor with a substrate and a thermocouple arrangement that is formed at a measurement position on the substrate, an increase in sensitivity can be achieved by way of a special geometry of the thermocouple arrangement and/or the selection of the material for the substrate. In addition, a manufacturing method is proposed for the inventive sensor. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates, in general, to wet flue gas desulfurization (WFGD) systems and, in particular, to a new and useful method of reducing the pressure drop in a downflow/upflow WFGD system and improving its collection efficiency by converting it to an upflow single-loop WFGD system.
2. Description of the Related Art
The desulfurization of flue gas, particularly flue gas from power plants, has been the subject of considerable study. Air quality laws, both at the federal and state level, have set increasingly stringent emission standards especially for such known pollutants as sulfur oxides. Because coal and oil-fired electrical power generating plants can discharge large quantities of sulfur oxides as combustion by-products, much effort has focused on the desulfurization of flue gas to reduce power plant sulfur dioxide emissions to permissible levels.
Thus, sulfur oxides, principally present as sulfur dioxide, are found in the flue gases discharged by coal and oil-fired and other fossil fuel-fired electrical power generating plants, refuse-to-energy plants, and the waste gases from other industrial processes. In addition, sulfur-containing gases, notably sulfur dioxide, may be formed in the partial combustion or gasification of sulfur-containing fuels, such as coal or petroleum residuals. The control of air pollution resulting from the discharge of sulfur dioxide into the atmosphere has thus become increasingly urgent.
The most common flue gas desulfurization process used with coal and oil-fired electrical generating power plants is known as “wet scrubbing”. In this process the sulfur dioxide-containing flue gas is scrubbed with an aqueous alkaline solution or slurry reagent comprised of lime, limestone, soda ash, or other chemicals including sodium, magnesium and calcium compounds and may include any number of additives to enhance removal, control chemistry, and reduce chemical scale.
The technology for wet scrubbing provides gas-liquid contact in a number of differently configured systems. One of the more prominent of these systems is comprised of a downflow quencher and an upflow absorber. The hot flue gas to be treated enters the quencher which is equipped with a venturi scrubber or spray headers connected to a slurry or water source to produce droplets that promote rapid cooling of the hot flue gas as it flows downwardly through the quencher. After leaving the quencher, the cooled flue gas discharges into a lateral passageway and flows therethrough and then upwardly through the absorber where it is scrubbed with an alkaline slurry reagent where the gas flow is countercurrent to and in intimate contact with the slurry reagent. The slurry reagent is introduced into the absorber through spray header nozzles and flows over packing or trays. Mist eliminators are included near the absorber outlet to remove additional moisture from the flue gas.
While the downflow/upflow WFGD system generally provides the sulfur dioxide removal effect, it experiences a pressure loss higher than that of a contemporary single-loop WFGD system of the same capacity. It, then, follows that the downflow/upflow WFGD system requires more fan power and more pump power than the single-loop WFGD system. This, in turn, increases the operating and maintenance costs of a downflow/upflow WFGD system when compared to a single-loop WFGD system of the same capacity.
In other words, the present invention makes it possible to decrease the flow resistance of the flue gas and thereby reduce the operating and maintenance costs.
As noted, the trend in pollution control has been towards increased stringency, such that many facilities face the need to upgrade or retrofit their existing pollution control equipment to achieve better performance. In addition owners/operators are often interested in upgrading or retrofitting existing pollution control equipment to realize the benefit of lower operational and maintenance costs from improved efficiency. In many situations, the retrofitting or upgrading of an air pollution control system is difficult due to space and/or power consumption considerations. A benefit of the present invention is that it addresses both of these conditions by conforming the retrofit to the existing space and by lowering fan power and pump power requirements through a decrease in pressure loss across the pollution control system, and improved effectiveness in the removal of sulfur dioxide from the flue gases. The present invention can provide pressure drop reductions across the system of about 5 inches water gage.
SUMMARY OF THE INVENTION
The present invention provides a method of reducing the pressure drop in a downflow/upflow WFGD system by converting it to an upflow single-loop WFGD system. The downflow/upflow system includes a downflow quencher and an upflow absorber and a lateral flow passageway therebetween. The downflow quencher is comprised of a venturi scrubbing device mounted in the duct work used to convey the incoming flue gas through the quencher for discharge into the lateral passageway for flow therethrough to the absorber. As a practical matter, venturi scrubbing devices, even those claimed to utilize very fine droplets, actually utilize droplets which are much larger than the optimal size. The primary methods heretofore utilized in improving the collection efficiency of a venturi scrubber have been to decrease the size of the throat or to increase the overall rate at which gas flows through the system. Both of these methods increase the differential velocities between the contaminant particles and the liquid droplets as they pass through the throat of the venturi scrubber This causes more interactions between particles and droplets to occur, thereby improving contaminant removal. However, increasing the collection efficiency in this manner comes at a cost of significantly higher energy input into the system, thereby resulting in higher operating costs. The extra energy is expended due either to the increased overall resistance attributable to the reduced throat diameter or to the increased overall gas flow rate through the venturi scrubber. In either case, the pressure drop across the venturi is increased and greater fan and pumping capacity is required.
The method according to the present invention replaces the duct work, the quencher and, except for an alternate embodiment hereinafter described, the lateral passageway with a bypass that conveys the incoming flue gas directly to the absorber. The quenching zone is transferred to the absorber and replaced by a spray level. The spray level includes a plurality of spray nozzles mounted on headers arranged parallel to one another. The nozzles spray an aqueous slurry of sulfur dioxide-reducing reagent within the spray zone to contact the flue gas while descending through the absorber counter-currently to the flow of flue gas, the slurry reagent is collected in the absorber sump or reaction tank and a portion of it is recycled for contact with the flue gas flowing through the absorber. The piping used to supply the slurry reagent to the quencher in the replaced duct work may be rerouted to the spray nozzle headers located in the absorber. The replacement of the bypassed quencher with a level of spray nozzles improves overall sulfur dioxide removal from the flue gases flowing through the system. An awning is mounted over the absorber inlet to prevent the slurry reagent from entering the inlet, and to initially deflect the incoming flue gas in a downward direction thereby achieving a more uniform distribution of the flue gas in its upward flow through the absorber. The bypass is configured to have a lesser number of turns than the duct work thereby reducing pressure losses. The front wall of the absorber is extended below the absorber inlet and becomes the front wall of the sump so as to accommodate the replacement of the lateral passageway with the bypass and the connecting of the bypass with the absorber. An overflow conduit is added to the front wall of the sump to maintain a desired or preset level of slurry reagent and contaminant particles in the sump, with any excess slurry reagent and contaminant particles being discharged through downcomers to a holding tank. The bypass, the awning, and the front wall of the sump are fabricated from alloys that are corrosion-resistant to both oxidizing and reducing media, and are resistant to localized corrosion attack.
An optional standby quencher may also be provided in the bypass for emergency use.
Flow guide elements may be mounted in the bypass such as turning vanes around corners so as to promote laminar flow of the flue gases, particularly around sharp corners in the duct work, and thus further reduce pressure losses.
The lateral passageway need not be replaced, provided that it is restructured in that its flue gas inlet opening located on the roof is closed off and replaced by a flue gas inlet opening on the front wall. The bypass is then connected to the portion of the passageway front wall bordering the relocated flue gas inlet opening. A set of headers and nozzles may have to be added on the gas side of the passageway roof as part of the restructuring so as to provide a spray of alkaline solution to primarily prevent the overheating of the roof.
It should be noted that removal of the duct work and the venturi scrubber type quencher will not only reduce fan power and pump power requirements due to reduced pressure drop across the system, but also result in the elimination of the costly maintenance associated with the venturi scrubber throat.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and its advantages will be more appreciated from the following detailed description, especially when read in light of the accompanying drawings, wherein:
FIG.1 is a schematic sectional side view of a downflow/upflow WFGD system known in the art;
FIG. 2 is a schematic sectional side view of an upflow single-loop WFGD system derived from the system shown in FIG. 1 after utilizing a method according to the present invention;
FIG. 3 is a schematic sectional side view of an alternate embodiment of the present invention, and depicts an emergency quencher mounted in the bypass;
FIG. 4 is a schematic sectional side view of another alternate embodiment of the present invention, and depicts turning vanes mounted in the bypass;
FIG. 5 is a schematic sectional side view of a further alternate embodiment of the present invention, and depicts the bypass connected to the lateral passageway; and
FIG. 6 is a schematic sectional side view of still another alternate embodiment of the present invention, and depicts an arrangement for accommodating a partitioned sump.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention has preferred application to utility boiler flue gases which is the embodiment that will be described for purposes of illustrating the invention and its advantages. However, the invention is not limited to the illustrated embodiment, and effluents from all types of combustion sources, utilizing packed or other types of scrubbing apparatus, and a wide range of reagents in co-current and/or counter-current applications are envisioned.
Reference will hereinafter be made to the accompanying drawings wherein like reference numerals throughout the various figures denote like elements.
Referring now to the drawings, and particularly to FIG. 1, The downflow/upflow WFGD system 10 , illustrated herein, is known in the art and embodies a flue gas duct 11 for receiving incoming flue gas 12 , such as from a coal-fired utility or industrial boiler (not shown), and preferably cleaned of particulates such as by an electrostatic precipitator (not shown) or a fabric filter (not shown). The flue gas 12 is conveyed from the duct 11 by duct work 17 , located between the cut points 52 and 53 , and through the quencher 14 which is mounted in the duct work 17 . The quencher 14 comprises a venturi scrubber 16 , and as is known, venturi scrubber 16 is formed of an inlet cone 18 , a throat 20 and an outlet cone 22 .
As is also known, as the flue gas 12 travels through the venturi scrubber 16 it is accelerated by the reduced cross section of inlet cone 18 and throat 20 , and it is then decelerated by the increased cross section of outlet cone 22 . The process of accelerating and decelerating the flue gas flow facilitates interactions between the droplets of scrubbing fluid and the and acid gases particles in the flue gas 12 , such that a portion of the contaminants particles are captured by the droplets and removed from the flue gas 12 .
In the illustrative example, an alkaline slurry reagent is supplied via conduit 24 to the venturi scrubber 16 and sprayed into the flue gas stream through spray nozzles 25 mounted on spray headers 23 . The nozzles 25 provide a uniform spray of relatively coarse droplets suspended in concurrent or cross-current contact with the flue gas 12 in the throat 20 . The disposition of the sprays relative to the downwardly converging walls of the inlet cone 18 is such as to provide a wash along the lower regions of these walls to keep them relatively clean and to prevent the buildup of deposits on the wall surface.
After leaving the venturi scrubber 16 , the flue gas, the sprayed slurry reagent and the captured contaminant particles flow co-currently downward and are discharged downwardly through the inlet opening 27 of a lateral passageway 30 . The inlet opening 27 is located on the roof 29 of the passageway 30 and adjacent its front wall 47 . The flue gas, the sprayed slurry, and the captured contaminant particles flow over and in contact with the slurry reagent and contaminants 31 collected in the reaction tank or sump 32 . The slurry reagent and contaminants in the sump 32 are maintained at a desired or preset level with any excess slurry reagent and contaminants being discharged through downcomers 33 to a holding tank 35 . The quenched and partially scrubbed flue gas 12 enters the absorber 26 through the inlet opening 28 . Thus, the flue gas makes a 180° turn as it flows downwardly through the quencher 14 , laterally through the passageway 30 and upwardly through the absorber 26 . In its upward flow through the absorber 26 , the flue gas 12 passes through a perforated tray 21 that promotes gas-liquid contact, and is generally of the type disclosed by the present applicant in U.S. Pat. No. 4,263,021. Thence, the flue gas 12 flows through a spray zone 34 that comprises spray levels 36 a and 36 b where additional gas-liquid contact is achieved. The spray levels 36 a and 36 b include spray nozzles 40 mounted on a set of headers 38 . An alkaline slurry reagent is supplied to the headers 38 via manifolds, not shown, and conduit 43 . A disengagement zone 42 is provided above spray level 36 a before the flue gas 12 reaches the mist eliminator 44 . The mist eliminator 44 is equipped with chevrons 45 to remove additional moisture from the flue gas 12 . The scrubbed flue gas 12 leaves the mist eliminator 44 and exits from the absorber 26 through outlet 46 into the flue duct 48 for discharge through a stack (not shown).
In accordance with the present invention and with particular reference to FIG. 2, and as shown in FIG. 1, a duct section or duct work 17 is disconnected from the flue gas duct 11 at a cut point 52 and from the inlet 27 of the passageway 30 at a cut point 53 . The duct work 17 which includes the quencher 14 is thus removed from operation as part of converting the downflow/upflow WFGD system 10 into an upflow single-loop WFGD system 15 , shown in FIG. 2, and may be dismantled. As part of this conversion, and as shown in FIG. 2, a duct or bypass 56 is installed between flue gas duct 11 and the absorber 26 . The bypass 56 has one end connected to the flue gas duct 11 at the cut point 52 , shown in FIG. 1, and the other end connected to the portions of the absorber front wall 39 and the sump front wall 37 bordering on the inlet 28 of the absorber 26 . The passageway 30 , shown in FIG. 1, is thus removed from operation as part of the conversion, and may be dismantled. The bypass 56 receives the incoming flue gas 12 from the duct 11 and conveys it to the inlet 28 of the absorber 26 .
Also as part of the conversion, the function performed by the quencher 14 , shown in FIG. 1, is transferred to a quenching zone 58 located in the absorber 26 between spray level 36 b and the inlet 28 of absorber 26 . The quenching zone 58 consists of a spray level 60 . The spray level 60 is comprised of a set of headers 64 and spray nozzles 66 . An alkaline slurry reagent is supplied to the spray nozzles 66 through headers 64 via conduit 24 that is disconnected from the quencher 14 , shown in FIG. 1, and rerouted and reconnected through a manifold (not shown) to the headers 64 . Alternatively, a new conduit, not shown, may be installed to supply the alkaline slurry reagent to the spray nozzles 66 .
Further as part of the conversion, an awning 72 , generally of the type disclosed by the present applicant in U.S. Pat. No. 5,281,402, is mounted over the inlet 28 of the absorber 26 to prevent the slurry reagent from entering the bypass 56 , and to initially deflect the flue gas 12 in a downward direction as it enters the absorber 26 so as to achieve better distribution of the flue gas 12 in its subsequent upward flow through the absorber 26 . As it flows upwardly through the absorber 26 , the flue gas 12 passes through a perforated tray 21 that promotes gas-liquid contact, and thence through a spray zone 34 that comprises spray levels 36 a and 36 b where additional gas-liquid contact is achieved. The spray levels 36 a and 36 b include spray nozzles 40 mounted on a set of headers 38 . An alkaline slurry reagent is supplied to the headers 38 via manifolds, not shown, and conduit 43 . The spray nozzles 40 produce a spray of relatively coarse droplets suspended in countercurrent contact with the flue gas 12 for several seconds. A majority of the sulfur dioxide absorption from the flue gas occurs during this short contact time. A disengagement zone 42 is provided above spray level 36 a before the flue gas 12 reaches the mist eliminator 44 . The purpose of the zone 42 is to allow disengagement and return of the largest slurry droplets by gravity to the spray zone 34 . The mist eliminator 44 design in most wet scrubbers uses chevrons 45 to remove additional moisture from the flue gas 12 . Chevrons 45 are closely spaced corrugated plates that collect slurry deposits by impaction. The scrubbed flue gas 12 leaves the mist eliminator 44 and exits from the absorber 26 through outlet 46 into the flue duct 48 for discharge through a stack (not shown). Because the flue gas 12 leaving the absorber 26 is saturated with water vapor, surface condensation is inevitable. This condensate can become severely acidic and calcium salts can deposit on the walls. Two approaches are used to minimize these effects, flue gas reheat (not shown), and flue duct and stack lining (not shown). In the latter approach, the flue duct 48 is lined with corrosion resistant materials, and the stack is lined with acid resistant brick or other suitable material. A drainage system (not shown) is also included to accommodate the condensed water vapor.
Additionally as part of the conversion, the front wall 39 of the absorber 26 is extended below the inlet 28 of the absorber 26 and becomes the front wall 37 of the sump 32 . An overflow conduit 41 is added to the front wall 37 of the sump 32 to maintain a desired or preset level of slurry reagent spent slurry and contaminant particles 31 in the sump 32 , with any excess slurry reagent and contaminants 31 being discharged through downcomers 33 a and 33 b to the holding tank 35 .
Turning now to FIG. 3, there is shown an alternate embodiment depicting fragmented portions of the flue gas duct 11 and the absorber 26 , the bypass 56 , the awning 72 , and the direction of flow of the flue gas 12 through the duct 11 , the bypass 56 and the absorber 26 . In accordance with this embodiment, a standby quencher 76 is mounted in the bypass 56 for emergency use. For example, the quencher 76 may consist of a set of headers 78 and spray nozzles 80 . An alkaline solution or water is supplied via conduit 82 to a manifold 84 and thence through headers 78 to the spray nozzles 80 . Control apparatus, not shown, may be provided to automatically activate the standby quencher 76 whenever the flue gas 12 being conveyed through the bypass 56 exceeds a desired or preset temperature.
In FIG. 4, there is shown another alternate embodiment of the present invention depicting fragmented portions of the flue gas duct 11 and the absorber 26 , the bypass 56 , the awning 72 , and the direction of flow of the flue gas 12 through the duct 11 , the bypass 56 and the absorber 26 . In accordance with this embodiment, flow guiding means in the form of turning vanes 74 are mounted in the corner 88 of bypass 56 to direct the flow of flue gas 12 around the corner 88 and to promote uniform flow of the flue gas 12 and thus reduce the pressure drop across the bypass 56 by reducing the turning losses at the corner 88 .
In FIG. 5, there is shown a further alternate embodiment of the present invention depicting fragmented portions of the bypass 56 and the absorber 26 , and the direction of flow of the flue gas 12 through the bypass 56 and the absorber 26 . In accordance with this embodiment, the bypass 56 does not replace the lateral passageway 30 of FIG. 1, instead, it discharges the flue gas 12 into passageway 30 which then conveys it to the absorber 26 . The retained passageway 30 has been restructured to include the closing of the inlet opening 27 located in the roof 29 of passageway 30 and shown in FIG. 1, or the installation of a new roof without an inlet opening, and the making of an inlet opening 86 in the front wall 47 of passageway 30 to receive the flue gas 12 being discharged from the bypass 56 which is connected to the portion of the front wall 47 bordering the opening 86 . A set of headers 90 and spray nozzles 92 may have to be added to the gas side of the roof 29 , as part of the restructuring of passageway 30 , to prevent the flue gas 12 from overheating the roof 29 . An alkaline solution is supplied by a conduit 94 through a manifold, not shown, and thence through headers 90 to the spray nozzles 92 . Control apparatus, not shown, may be provided to create a shield of alkaline spray protecting the roof 29 whenever the flue gas exceeds a desired or preset temperature. The flue gas 12 entering the passageway 30 flows over and in contact with the slurry reagent and contaminants 31 collected in the sump 32 . The excess slurry reagents and contaminants 31 in the sump 32 are discharged through downcomers 33 into the holding tank 35 .
In FIG. 6, there is shown still another embodiment of the present invention depicting fragmented portions of the bypass 56 , the awning 72 and the absorber 26 , and the direction of flow of the flue gas 12 through the bypass 56 and the absorber 26 . In accordance with this embodiment, the sump 32 is divided into sections 32 a and 32 b . The partition 49 that divides the sump 32 into sections 32 a and 32 b is provided with an opening 51 which enables excess slurry reagent and contaminants 31 in section 32 b , beyond that being discharged through downcomer 33 b to the holding tank 35 , to flow from section 32 b to section 32 a and thence through the overflow conduit 41 located in the front wall 37 of the sump 32 . The excess slurry agent and contaminants 31 are discharged from the overflow conduit 41 through downcomer 33 a into the holding tank 35 .
Although the present invention has been described above with reference to particular means, materials and embodiments, it is to be understood that this invention may be varied in many ways without departing from the spirit and scope thereof, and therefore is not limited to these disclosed particulars but extends instead to all equivalents within the scope of the following claims. | A method of reducing the pressure drop in a downflow/upflow wet flue gas desulfurization (WFGD) system and of improving overall sulfur dioxide collection efficiency by converting the downflow/upflow WFGD system to an upflow single-loop WFGD system. The method includes the replacing of the downflow quencher and related duct work with a bypass for connecting the incoming flue gas duct with the upflow absorber, and the adding of a quenching zone in the absorber comprised of spray headers. | 8 |
TECHNICAL FIELD
The present invention relates to a photofinishing system wherein images of a wide variety of types such as photographic images from an inkjet printer are laminated in a subsequent operation. More particularly the present invention relates to such a system having a buffer between the inkjet printer and the laminator for transporting the printed images from the inkjet printer to a laminator.
BACKGROUND OF THE INVENTION
In photofinishing operations it is conventional to develop and print photographs on roll stock photographic paper having a width that generally accommodates one size of print. After printing out a roll of photos on a strip of the roll stock, the strip is cut to provide the individual prints. Dedicating a given size of roll stock to the production of a given size photo is less flexible for fulfilling print orders and slows throughput. It requires the photofinishing operation either to have multiple machines, each dedicated to a given size of photo or it places a burden on the operator to change the print media from one size to another after completing orders.
Advancements in photofinishing allow for the production of photographs by ink jet printers, laser printers and other photofinishing printers including silver-halide systems that receive digital input and employ conventional wet chemistry output. Moreover the use of computers in connection with these advancements allows for further improvement. For example, it is not necessary to use roll stock having the width of a desired finished photo. A photofinishing printer now can generate photos of various sizes on a single sheet of print media. Also the images can be manipulated to nest various image sizes on a single larger sheet. Accordingly, a sheet or roll stock of a single width can be used to generate prints of various sizes for a single customer order.
Currently, the photofinishing printer of choice is an inkjet printer. Inkjet printing comprises a scan and print technology involving an intermittent indexing of the print medium. In this respect the print medium such as photographic paper is fed to the printer and is held stationary by the printer while an inkjet print head makes a printing scan across the paper. The paper then is indexed for a second scan of the print head. In this fashion a plurality of scans will generate the photographic image.
Inkjet prints historically have been subject to problems such as durability and fading because of limitations put on ink systems used in inkjet printers. For example the printed image can be eroded by abrasion. Both the durability and fading problems are solved by the application of a protective laminate to the image after printing. A protective laminate is applied by passing the print continuously through a laminator in order to apply a protective transparent layer to the surface of the print. While lamination provides an acceptable solution to image problems associated with inkjet prints, the start and stop indexing motion inherent in inkjet printing conflicts with the operation of a laminator, which typically operates with continuous motion.
Accordingly, to applicant's knowledge and for the reasons noted above, an inkjet printing system and a laminator system have not been linked in a continuous sequential operation and heretofore a sheet comprising the print output of an inkjet printer was not directly fed into a laminator. Instead the printed sheets were simply removed from the printer and accumulated for later feeding one at a time to a laminating device.
Feeding the printed sheet output of an inkjet printer to a laminator presents several problems. For example, the inkjet printer used in photofinishing operations typically can produce printed sheets in a variety of lengths. Thus a transport mechanism for feeding the printer output to the laminator must be able to accommodate each of the various lengths of prints that are output by the printer. Also, in order to minimize space, it is preferred that the transport mechanism receive a leading portion of the printed sheet from the printer while a trailing portion is still in the grip of the printer. Thus a leading edge of the printed sheet should enter the transport mechanism before the sheet is completely printed. However, when the leading edge of the partially printed sheet is in the grip of the transport mechanism, the transport mechanism must not interfere with the start/stop indexing motion of the portion of the sheet still in the printer. Any resistance to this motion or any attempt of the transport mechanism to tug on the sheet prior to the completion of the printing operation will likely degrade the print quality.
After the printing operation is completed, the printer will eject the printed sheet at a continuous speed that generally is faster than the start/stop indexing motion of the printing operation. The transport mechanism must accommodate this faster movement of the sheet and then deliver the sheet to the laminator. As the transport mechanism moves the leading edge of the sheet to the laminator, the laminator will grip the leading edge and tend to draw the sheet from the transport mechanism. To prevent damage to the sheet or the printed image, the transport mechanism must offer no resistance to the drawing out of the sheet.
Thus a transport mechanism for disposition between an inkjet printer and a laminator must have several attributes. It should be able to accommodate various sizes of prints up to the longest produced by the printer. It must not interfere with printing by resisting the start/stop indexing motion of the inkjet printing operation or attempt to tug on a partly printed sheet. It also should allow rapid deployment of the sheet from the printer at the end of the printing operation, convey the sheet to the laminator and not resist the drawing of the sheet from the buffer by the laminator.
OBJECTS OF THE INVENTION
Accordingly, it is an object of the present invention to provide a transport mechanism for handing off a work piece from one device to another wherein the devices have different processing speeds.
Another object of the present invention is to provide a transport mechanism between an ink jet printer and a laminating device for delivering a printed sheet from the printer to the laminator wherein the laminator has a faster processing speed than the printer.
A further object of the present invention is to provide a transport mechanism for receiving a printed sheet output of an inkjet printer and delivering the printed output directly to a laminator wherein the transport mechanism accommodates two processing speeds of the printer and a single operating speed of the laminator.
Yet another object of the invention is to provide a method for delivering a printed sheet produced at a first processing speed by an inkjet printer to a laminator operating at a different processing speed.
SUMMARY OF THE INVENTION
In the present invention, a transport mechanism is provided that includes a buffer disposed to receive a printed page output of an inkjet printer and deliver the printed page or sheet to a coater/laminator that applies a protective lamination to the printed surface. The sheet moves through the printer at a first speed during the printing operation, the first speed being the average of a start/stop movement required for inkjet printing namely a peak speed during the indexing of the paper and a stoppage or pause for printing. The printed output then ejects from the printer at a speed that is faster than the first (average) speed. Subsequently, the printed sheet moves through the laminator at yet another speed usually faster than the average first speed.
The buffer, disposed between the printer and laminator, includes a track that defines a path of travel long enough to accommodate the longest sheet produced by the printer. The buffer receives the printer output in a manner that accommodates the two speeds of the printer without interfering with the operation of the printer. The buffer then delivers the printer output to the laminator in a manner that accommodates the operating speed of the laminator.
The buffer includes driven rollers arranged along the track for moving the printed sheet through the buffer preferably at a constant speed that is between the eject speed of the printer and the operating speed of the laminator. Each of the rollers includes a one way clutch that allows the rollers to overrun a drive shaft in response either to the ejection of a printed sheet from the printer or to the laminator tugging on a sheet leaving the buffer. In addition, the driven rollers include a slip clutch between a drive motor and the drive shaft that limits the drive force exerted by the rollers on a printed sheet. This prevents the driven rollers from tugging so hard on a sheet that is still within the grip of the inkjet printer at a time prior to ejection that the image quality is reduced.
Accordingly, the present invention may be characterized in one aspect thereof by a transport buffer for transporting a flexible sheet along a path of travel between an outlet of a first workstation and an inlet of a second workstation, the first workstation intermittently delivering the flexible sheet to the buffer at a first peak speed and a first average speed in a first mode of operation (such as an inkjet printing operation) and continuously delivering the flexible sheet to the buffer at a second speed in a second mode of operation(such as when the printed sheet is ejected from the printer), and the second workstation taking up the flexible sheet at a third speed, the buffer comprising:
a) a drive roller arranged along the path of travel for engaging and moving the flexible sheet through the buffer, the drive roller being operatively connected to a motor for driving the rollers at a substantially constant drive speed;
b) a first clutch having a predetermined torque limit allowing slippage of the drive roller when the constant drive speed is greater than the speed at which the flexible sheet is moving from the first workstation and into the buffer; and
c) a second clutch allowing the drive roller to rotate at a speed faster than the constant drive speed to permit movement of the flexible sheet into the buffer from the first workstation at a speed greater than the constant drive speed.
In another aspect, the present invention may be characterized by a method of transporting a flexible sheet moving from a first workstation operating at a first average speed and a first peak speed faster than the average speed in a first mode of operation and at a second speed in a second mode of operation, to a second work station operating at a third speed greater than the first average speed comprising;
a) engaging the sheet leaving the first workstation with a rotating driver for moving the sheet along a path of travel at a constant speed from the first workstation to the second workstation;
b) limiting the torque applied by the rotating driver for moving the sheet in the buffer when the constant speed is greater than the speed at which the sheet is moving from the first work station; and
c) freeing the rotating driver to rotate at a speed greater than the constant speed to permit movement of the sheet into the buffer at a speed greater than the constant speed.
DESCRIPTION OF THE DRAWINGS
FIGS. 1-6 are schematic views showing steps in the operation of the buffer of the present invention; and
FIG. 7 is a perspective view showing a driven roller mechanism as used in the buffer.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings FIG. 1 shows a schematic representation of the buffer of the present invention generally indicated at 10 . The buffer is disposed between a photofinishing inkjet printer 12 and a coater/laminator 14 located downstream of the printer. The inkjet printer is conventional and need not be described in detail except to say that it includes a print head 16 containing a plurality of nozzles (not shown).
The print head is mounted for movements back and forth across a photographic paper 18 (in a direction normal to the plane of the figure) wherein a portion of a photographic image is printed with each scan or pass of the print head. While the paper can be fed in sheets to the printer, it is preferred that the paper supply be a roll 20 so the supply is continuous. Drive rollers 22 within the printer feed the paper to the print head and step the paper forward for each printing pass of the print head. Thus the movement of the rollers is intermittent in that the paper first is indexed or stepped forward at a peak speed, then movement is stopped and the paper is held for a printing pass of the print head. After the pass of the print head is complete, the paper is indexed forward again and stopped for the next pass. In this fashion a plurality of passes or scans across the paper will generate the photographic image and the speed through the printer in a first mode of operation is an average taking into consideration the peak speed or index time and the pause time for each scan. Each indexing of the paper is a precise movement that is adversely affected by any external resistance to the movement of the paper or by tugging on the paper. The force that can be applied to the paper without degrading quality depends on the particular printer. In one embodiment of this invention, the printer can sustain a tugging force of just under 100 grams without degrading the image.
After completion of a printing operation, the printed portion is ejected from the printer by the rollers 22 in a second mode of operation comprising a continuous movement of the printed portion. The printed portion then is cut from the continuous supply by a knife 24 . Accordingly, for purposes of the present invention it should be appreciated that the start/stop movement during the printing operation in a first mode of operation is at an average first speed whereas the ejection of the completed print occurs in a second mode of operation at a second speed that is faster than average speed of the printing operation.
In some printers of the type with which the present invention may be employed, the printer may occasionally reverse the motion of the paper during printing. This most commonly occurs during servicing of the printer to reduce waste.
From the printer, the cut off printed portion referred to hereafter as a “segment” enters buffer 10 . The buffer has an internal track that defines a path of travel (indicated by dotted line) for delivering the segment to the downstream laminator 14 . The laminator also is conventional and need not be described in detail. It is sufficient to say that the laminator receives the segment and applies a protective laminate (not shown) to the printed surface of the segment as the segment moves through the laminator. Preferably, the laminator 14 operates at a third speed somewhere between the average first speed of the printer and the ejection or second speed of the printer. More generally, the laminator operates at a speed faster than the first average speed. Accordingly, one function of the buffer 10 is to permit the hand off of the segment between the two devices operating at different speeds.
To accommodate the hand off, the buffer 10 of the present invention defines a path of travel, as shown in dotted line in the Figures, that is preferably at least as long as the longest segment produced by the printer. Disposed along this path of travel is a series of drive rollers 26 . These rollers nip against the segment and are driven so as to move the segment through the buffer preferably at a constant speed that most preferably is faster than the average first speed of the printer and slower than the ejection speed of the printer. Contact switches 28 , 30 at the inlet and exit respectively of the buffer operate to start and stop the action of the rollers 26 .
A typical drive roller mechanism is shown in FIG. 7 . As shown in FIG. 7, the drive roller mechanism includes one or more drive rollers 26 carried by a drive shaft 32 . The drive shaft, in turn, is connected to a drive motor 39 . A one-way clutch 34 transmits force from the drive shaft to each roller for driving the roller in the direction indicated by arrow 36 . The one-way clutch also permits the roller to overrun the shaft so the clutch frees the roller to rotate faster than the drive shaft in the direction of arrow 36 . A slip clutch 38 is disposed between the drive shaft 32 and the motor 39 . The slip clutch limits the torque or drive force exerted by the roller on the segment in the direction of arrow 36 for purposes set out hereinbelow. Preferably, the force limit of the slip clutch is set somewhere below the maximum force that can be tolerated by the printer without degrading the image, to provide a safety factor. When used with the printer described above, that can sustain just under 100 grams of force without degrading print quality, a slip clutch limit of about 60 grams can be used.
Operation will be described beginning with reference to FIG. 1 wherein the photographic paper is being fed through the printer. As an image is printed, rollers 22 intermittently index the paper by the print head 16 . At each pause in the indexing cycle, the rollers hold the paper and the print head scans across the paper to print a portion of the image. As the start/stop printing movement continues, the leading edge 40 of the paper enters the buffer 10 . Eventually the paper progresses into the buffer and engages the contact switch 28 . This starts the operation of the drive rollers 26 within the buffer. The drive shaft operating through the slip clutch 38 and one-way clutch 34 drives these rollers at a constant speed that, as noted above, is faster than the printing speed of the printer but slower than the eject speed.
When the leading edge 40 of the paper enters through the nip between the first set of buffer drive rollers 26 A, as shown in FIG. 2, these rollers will begin to tug on the paper. This invention limits the tugging force to a level that will not tend to disrupt the printing operation and degrade the print quality. The slip clutch or torque limiter 38 that couples the drive motor 39 to the drive shaft 32 and the one-way clutch 34 between the drive shaft and the rollers are set up to prevent the rollers 26 A from tugging on the paper while movement of the paper is paused. This is done by setting the slip clutch 38 so as to limit the drive force exerted on the paper by the rollers 26 to a level below that which can cause an adverse effect on print quality.
As the paper is indexed forward for the next printing scan of the print head, the engagement of the paper in the nip between rollers 26 A must not resist the sudden and rapid forward stepping of the paper at a peak speed. Such resistance also will adversely affect print quality. To prevent such resistance, the one-way clutch 34 between the drive shaft 32 and the roller allows the rollers to overrun the shaft. In this fashion the paper, as it is stepped forward, will exert sufficient force on the rollers 26 A to overrun the shaft so there is little or no resistance to such forward movement.
After the printing operation is complete, the printer ejects the printed portion of the paper. If the paper is ejected at a speed faster than can be accommodated by the rollers 26 , the slip clutch allows theses rollers to overrun the shaft so the paper is moved rapidly into the buffer. After the printed portion is ejected, movement stops so the knife 24 can cut a printed segment 42 from the paper in the printer (FIG. 3 ). The buffer drive motor 39 is turned off while the paper is held for cutting. After the segment 42 is cut from the paper supply, the drive motor 39 is turned on to drive rollers 26 of the buffer to move the segment through the buffer at a constant speed and deliver it to the downstream laminator 14 (FIG. 4 ). Meanwhile, the printer starts another printing operation.
FIG. 5 shows the printed segment 42 entering the laminator. The leading edge 40 of the segment enters the nip between laminator driven rollers 44 so the segment is pulled into the laminator. At this point, a trailing portion of the segment may still be in the grip of drive rollers 26 in the buffer. Accordingly, as the segment 42 is pulled into the laminator, the one-way clutches 34 associated with each roller 26 allows the segment to be pulled into the laminator at a speed faster than the transport speed through the buffer by allowing the segment to overrun the speed of shaft 32 . Conversely, if the laminator operates slower than the buffer, the slip clutch 38 will prevent the buffer rollers from forcing the segment into the laminator.
FIG. 6 shows the segment 42 completely within the laminator as a subsequent and shorter segment 46 is being transported through the buffer and the leading edge 48 of yet another printed portion is entering the buffer.
Thus it should be appreciated that the present invention accomplishes its intended objects in providing a buffer for handing off a work piece from one device to another wherein the devices, such as an inkjet printer and a coater/laminator, that may have different processing speeds. The buffer located between the two devices defines a path of travel that preferably is longer than the longest work piece produced by a first device so that the work piece is never in the grips of both devices at the same time. This is especially significant where the work piece is segment comprising the printed output of an inkjet printer and the second or downstream device is a laminator for applying a protective coating to the printed segment. One-way clutches on the drive means for moving the work piece through the buffer accommodates the indexing motion of the inkjet printer and allows such indexing to occur at speeds higher than the transport speed through the buffer. The clutches also allow the downstream device, such as a coater/laminator, to pull a work piece, such as a printed output of an inkjet printer, from the buffer at a speed greater than the transport speed through the buffer.
Conversely, slip clutches in the buffer drive limit the force exerted on the work piece by the buffer drive rollers. This insures that an upstream device can stop the movement of the work piece to perform an operation on one portion of the work piece while another portion of the work piece is in the grip of the buffer.
In a preferred embodiment, the present invention provides a buffer between an ink jet printer and a laminating device wherein the laminator may have a faster processing speed than the printer. The buffer is adapted to receive the printed output of an inkjet printer and deliver the output directly to a laminator wherein the buffer accommodates two processing speeds of the printer and a single operating speed of the laminator. | A buffer for transporting a flexible work piece such as a printed sheet between a first and a second workstation having different operational speeds. The buffer has drive rollers arranged along a path of travel from the outlet of the first station to the inlet of the second for moving the work piece through the buffer at a constant speed that may be different than the operational speeds of the workstations. A slip clutch limits the torque applied by the drive rollers should the constant speed of the buffer be greater than the speed at which the sheet is moving through the first work station and a one-way clutch allows the drive rollers to overrun a drive shaft to permit the sheet to move into and out of the buffer at a speed greater than the constant speed. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to semiconductor devices, and more specifically relates to such devices having a planar configuration, which are particularly suitable for use in high density integrated circuits, and also relates to a method of fabrication of such devices.
As the semiconductor devices in integrated circuits become smaller and more closely packed, the upper layers of the devices, such as the metal interconnect patterns, must accommodate more abrupt changes in surface topography caused by the smaller lateral dimensions of the devices. In some cases, deviations from planarity, sometimes called "steps", cannot be covered completely, so that discontinuities occur in the overlying metal layer. The problem is accentuated as more layers are added, such as in the case of interconnected multi-level integrated circuits, creating more complicated surface topographies having more and larger steps.
Etching techniques are known which will "planarize" a non-planar surface. For example, U.S. Pat. No. 4,025,411 describes a process in which the non-planar surface of a semiconductor device is made planar by first applying a layer of liquid photoresist over the uneven surface, then allowing the photoresist to solidify, and finally etching the surface by a physical etching method (for example, RF sputter etching or ion milling) which removes the photoresist and the underlying material at about the same rate. Other planarization techniques for use with solid state devices are described in U.S. Pat. Nos. 4,073,054; 4,455,193; and 4,470,874.
As device miniaturization approaches the sub-micron level, another problem is encountered, namely line width control, or LWC, that is, the ability to print and etch a line within the required dimensional tolerances. Thus, for example, it becomes difficult in the fabriction of MOS (metal oxide semiconductor) transistors to accurately control the dimensions of a gate electrode having a length of 1 micron or less. Such a gate is typically formed by first depositing a polysilicon layer over an insulating oxide layer, masking the polysilicon layer, and then etching away the unmasked portions of the polysilicon layer to leave a gate electrode of the desired configuration. The materials currently in use for etching polysilicon generally cannot provide the desired LWC due to a tendency both to attack the photoresist and to etch the polysilicon isotropically, resulting in undercutting of the mask.
Still another problem encountered in device miniaturization is mask alignment tolerance. For example, the masks employed in the formation of the polysilicon gate and the overlying contact can generally be aligned with an accuracy of only about + or -0.75 microns. A total misalignment of up to + or -1.50 microns is possible between two levels aligned to a third.
Accordingly, it is a principal object of the invention to provide an MOS device having a planar configuration which will be particularly suitable for use in high density integrated circuits.
It is another object of the invention to provide a fabrication technique for such a planar semiconductor device which has improved line width and alignment control, and which is therefor particularly suitable for the production of sub-micron semiconductor devices.
SUMMARY OF THE INVENTION
In accordance with one aspect of the invention, there is provided an MOS device comprising source, drain and gate electrodes in a body of semiconductor material, which device is characterized in that the top surface of the gate is co-planar with the top surfaces of the source and drain. The body of semiconductor material is made up of a single crystal substrate and a conducting layer, usually a doped polycrystalline layer of the same material, on the surface of the substrate. At least the upper regions of the source and drain are located in the polycrystalline layer and these source and drain regions are separated by a trough in the polycrystalline layer. The gate electrode is located in this trough and is separated from the source and drain regions by insulating layers covering the walls and floor of the trough.
Electrical contact to the source, drain and gate regions is made in the conventional manner by etching holes in an overlying insulating layer above the source, drain and gate electrodes, and filling the holes with an electrical contact material. A metallization pattern is then formed in the conventional manner.
The location of the gate in the trough not only enables the top surface of the gate to be coplanar with the source and drain regions, but also enables improved dimensional control, by the avoidance of separate polysilicon masking and etching steps.
In accordance with a preferred embodiment, the gate and at least the upper regions of the source and drain electrodes all consist of doped polycrystalline semiconductor material, and the upper surfaces of these electrodes are covered with separate layers of a material having a higher electrical conductivity than the doped polycrystalline material.
In accordance with another preferred embodiment, there is included in the device at least one deep isolation channel of insulating material for electrically isolating the device from one or more laterally adjacent devices which are located in the semiconductor body.
In accordance with another aspect of the invention; there is provided a method for fabricating a planar MOS device, the method essentially including the following steps:
(a) selectively removing portions of a thick insulating layer on a single crystal semiconductor substrate to leave a mesa of insulating material on the substrate in a position corresponding to the desired gate region for the device;
(b) depositing a layer of source and drain material on the substrate and over the mesa to build up the surface of the semiconductor body as well as to define a gate trough therein;
(c) removing a portion of the source and drain layer in a manner to planarize the upper surface of the layer and also to expose the mesa;
(d) removing the insulating mesa from the gate trough;
(e) forming an insulating layer on the walls and floor of the gate trough;
(f) filling the gate trough with gate material;
(g) forming source and drain regions in the semiconductor body; and
(h) providing electrical connection to the source, drain and gate regions by first forming contacts to the source, drain and gate regions and then forming a metallization pattern for external electrical connection to these contacts.
In accordance with preferred embodiments of the method of fabrication, the source and drain layer and other layers such as the metallization layer are planarized by a technique which involves: depositing a layer of liquid photoresist on the uneven layer to be planarized in order to achieve a planar surface; allowing the photoresist to solidify; and then etching the photoresist and the underlying layer at approximately the same rate so as to remove the photoresist and at least the uneven portion of the underlying surface.
The gate may be formed by: forming a thin insulating layer over the entire exposed surface of the semiconductor body including the gate trough formed as described above; depositing a layer of gate material on this thin insulating layer; and planarizing the layer of gate material by the technique described above until all of the gate material has been removed except that remaining in the trough, so that the top surface of the gate is substantially co-planar with the top surfaces of the adjacent source and drain regions.
Where the source and drain material is a polycrystalline semiconductor material, the source and drain regions may be formed either by implanting dopants through the thin insulating layer into the semiconductor body, or by selectively removing the thin insulating layer from over the source and drain regions and then thermally diffusing the dopants directly into the semiconductor body, both in the known manner.
In still another embodiment of the invention, a slight modification of the method allows the formation of a bipolar device. In this embodiment, the oxide at the bottom of the gate trough is removed, or the bottom of the trough has been masked to prevent oxide formation, and an electrode layer is subsequently deposited directly on the silicon substrate, this would allow the formation of a bipolar device. This electrode layer, such as an appropriately doped polysilicon layer, becomes the emitter in the bipolar device, while the surrounding polysilicon is the base contact. It is also possible to form both MOS and bipolar devices on the same substrate by selective deposition or removal of oxide on the floor of troughs in laterally adjacent devices.
Other embodiments and variations of the invention will become apparent to those skilled in the art from the following detailed description, with accompanying drawings, of a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 through 17 are sectioned elevation views showing the sequential steps involved in the fabrication of an MOS device of the invention;
FIG. 18 is a detailed view of the trough of FIG. 9 including sidewall oxide spacers; and
FIG. 19 is a detailed view of the filled trough of FIG. 11 with the oxide layer removed from the bottom of the trough.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1, there is shown a body of single crystal silicon 10, having on its upper surface 100 a relatively thin insulating layer 11 of thermally grown silicon dioxide, (Si0 2 ). On top of this thermally grown oxide layer 11 is a patterned layer of photoresist material 12, which has been applied in a liquid state, allowed to solidify, and photolithographically patterned by techniques well known to those skilled in the art. It is preferred to spin the substrate after application of the liquid photoresist at a speed dependent upon the viscosity of the resist, in order to achieve a relatively smooth, planar surface. As is also known, such photoresist may be either positive or negative, although a positive resist is preferred for sub-micron devices due to the better line width control presently available.
Referring now to FIG. 2, there are shown two isolation channels 13 and 14, which have been etched via the holes in layer 12 through the oxide layer 11 into the semiconductor body 10. Exemplary dimensions for such isolation channels are up to about 1 micron wide by about 6 to 8 microns deep. These channels are preferably formed by a dry etching technique such as plasma etching. Etching through the thermal oxide layer and the semiconductor body may be in a single continuous step or in two steps done sequentially. After etching of the isolation channels, the photoresist is stripped away, thermal oxide layer 11 is removed and a new thermal oxide layer 15 is formed which includes the walls and floor of the channels, as shown in FIG. 3, in order to keep the surface of the semiconductor relatively free of contaminants.
Other forms of isolation may be used, but the channels are preferred in that they generally enable the achievement of higher device density.
Next, as shown in FIG. 4, a relatively thick insulating layer 16 is formed on the surface of semiconductor body 10, for example, by the vapor deposition of silicon dioxide. This vapor deposited layer, often referred to as "glass", also fills the isolation channels. A photoresist layer is then applied to the surface of the deposited oxide layer 16 and patterned 17 to mask the isolation channels and the gate region of the device. The oxide layer is then etched, and the photoresist is stripped, leaving isolation channels 18 and 19 and gate trough-defining oxide mesa 20, as shown in FIG. 5.
Next, a layer of undoped polysilicon 21 is deposited on the surface of the semiconductor body 10, covering the protruding portions of the isolation channels 18 and 19, as well as the gate trough-defining oxide mesa 20. As may be seen in FIG. 6, the upper surface of this polysilicon layer is uneven. The surface is then planarized by applying a layer of liquid photoresist 22 and spinning the resist to produce a planar surface. The photoresist layer 22 and a portion of the polysilicon layer 21 are then dry etched to achieve a planarized surface 101 in which polysilicon layer 23, gate trough-forming oxide mesa 20 and the isolation channel oxides 18 and 19 are all co-planar at their top surfaces, as shown in FIG. 7.
Next, the oxide mesa 20 is removed from the gate trough 25 by a wet chemical etch which is selective for oxides, during which the isolation channel oxides 18 and 19 are protected from removal by photoresist layer 24, as shown in FIG. 8. Following this, the photoresist layer is stripped away, and a new thin oxide layer 26 is thermally grown on the surface of the device as shown in FIG. 9. The portion of this layer 26 which covers the sides and bottom of the gate trough 25 will become the gate oxide for the device, to electrically isolate the gate from the laterally adjacent source and drain regions, and from the underlying substrate.
It will be recognized that the thickness of the gate oxide can be varied by techniques known in the art in order to vary the operating characteristics of the device. For example, rather than a thermally grown oxide layer, a relatively thick glass layer (e.g., about 2,000 to 3,000 Angstroms) may be formed in the gate trough, and then etched anisotropically to form oxide spacers 180 and 181 on the sides of the trough 25, as shown in FIG. 18. Alternatively, the thermal layer 26 may be grown under conditions which promote more rapid oxidation of the polysilicon sides than the single crystal silicon bottom of the trough.
This structure would be advantageous in providing additional isolation and thus reducing the Miller capacitance between the gate, source and drain regions of the device. Such reduced capacitance is advantageous, for example, in allowing reduced linewidths and consequently increased device density.
The next step is to deposit a layer 27 of gate material over the entire surface of the device, as shown in FIG. 10. Such a layer could be polysilicon, doped for example with phosphorus, to lower its electrical resistance. The uneven upper surface of layer 27 is planarized by spinning photoresist layer 28 onto layer 27, and then dry etching the layers until the only gate material remaining is confined to the gate trough 25, resulting in gate electrode 29 having a top surface co-planar with the remainder of the device surface 102, as shown in FIG. 11.
It will be recognized that a bipolar device may be formed instead of an MOS device, by removing the thermal oxide layer 26 from the bottom of trough 25 prior to filling trough 25 with electrode material. FIG. 19 shows a bipolar structure in which electrode 29 is the emitter, and the surrounding polysilicon 23 is the base.
The next step in the formation of the device is the formation of the source and drain regions. As is known, this is done by introducing selected dopants into the semiconductor body 10 using the gate electrode 29 as a mask. As is also known, this may be done by ion implantation through the thin thermally grown oxide layer 26 or by thermal diffusion directly into polysilicon layer 23 after oxide layer 26 has been removed. The resulting source and drain regions 31 and 32 may extend somewhat below polysilicon layer 23 into the single crystal silicon substrate 10, as shown in FIG. 12.
Polysilicon is used for the gate and upper regions of the source and drain electrodes because it is physically and chemically compatible with the single crystal silicon substrate (from the standpoint of adhesion and intimate interfacial contact), and is capable of being doped to the point of becoming a conductor. In addition, the underlying silicon can be doped (31, 32) by causing dopants to diffuse from the polysilicon layer above into the substrate. Of course, other conductive materials such as refractory metals could also be used.
Following formation of the source and drain regions, if the thermally grown oxide layer 26 has not been previously removed for doping, it is removed from the upper surface of the device. It is then preferred to form separate layers 33a, 33b and 33c over the tops of the source 31, gate 29 and drain 32 regions, which layers have a higher electrical conductivity than the doped polysilicon layers 29 and 23. By way of example, a refractory metal such as tungsten or titanium can be deposited on the surface of the device, and then thermally treated to promote the formation of a tungsten or titanium silicide having a resistivity on the order of from about 1 to 20 ohms per square. This is primarily advantageous in allowing the polycrystalline layers to be thinner, thus reducing sidewall capacitance. Alternative refractory metals include cobalt, platinum, molybdenum, and tantalum.
Next, the contacts for the source, drain and gate regions are formed by first forming a thick glass layer 34 over the entire surface of the device as shown in FIG. 13, and then etching contact holes 37 in glass layer 34 over the source 31, drain 32 and gate 29 areas as shown in FIG. 14. These holes 37 are filled with contact material such as doped polysilicon or a polysilicide such as tungsten silicide, produced for example by the low pressure chemical vapor deposition of tungsten, followed by thermal treatment to form the silicide. Glass layer 36 may then be selectively etched slightly, so that contacts 37a, 37b and 37c protrude above the etched surface 38, as shown in FIG. 15. Such etching may be done by dipping in a wet chemical etchant, as is known. The protrusions, referred to as "buttons", facilitate the making of good electrical contact to the subsequent metallization, and may aid in the alignment of subsequent layers.
A metal layer, shown as layer 39 in FIG. 16, is then formed on the surface of the device. This is typically a sputtered or evaporated aluminum, or aluminum alloy layer. The upper surface of layer 39 may be planarized in the manner described above, by spinning photoresist layer 40 onto the top of layer 39 and then dry etching back to achieve layer 41 having a planarized surface, designated 104 in FIG. 17. The metal layer is then formed into the desired metallization pattern by wet or day etching to produce separations 42 and 43 as shown in FIG. 17.
The etching of the oxide layer 16 to leave mesa 20, as shown in FIGS. 4 and 5 above, is a key element of the process, in that the height of the mesa 20 determines the depth of the subsequently formed gate trough 25, as well as the thickness of the source, drain and subsequently applied gate electrode.
In integrated circuits having laterally adjacent semiconductor devices, the constant height of the source, drain and gate electrodes from one device to another enables the production of high density device circuits with a high degree of uniformity, and the planarity of these devices reduces to a minimum the possibility of defects due to discontinuities in the metallization.
As will be appreciated, it is also possible to interconnect one or more adjacent devices, for example, by etching away a portion of an isolation channel to allow continuity between adjacent polycrystalline silicon layers.
The oxide mesas which are used to form the gate troughs can also be configurated in such a way that the later formation of the gate results in the interconnection of laterally adjacent devices as is known in connection with standard silicon gate processing. This could be significant in the fabrication of single function, multiple device circuits such as a static RAM memory cell.
In the final step of metallization, the upper surface is planarized as described in connection with FIG. 17. Of course, any number of additional planarized layers of devices or interconnections could be added, in a manner to preserve the overall planarity of the device. | An MOS device having a planar configuration in which the top surfaces of the source, drain and gate electrodes are coplanar, and the overlying electrical contact structure is also planar, is produced by a method of fabrication in which the gate is defined by forming an oxide mesa on a substrate, building up the substrate with semiconductor material around the mesa, removing the mesa, and filling the resultant trough with doped polysilicon to form the self-aligned gate. Line width and alignment control are enchanced. The planarity of the device and the improved dimensional control enable a reduction of device dimensions and consequently increased device density in integrated circuits. | 7 |
FIELD OF THE INVENTION
The present invention generally relates to a protective cover, and more specifically to a design with capability of protection, shielding and supporting.
BACKGROUND OF THE INVENTION
Smart phone is a popular portable device nowadays and become ubiquitous. With large display screen and a wide range of application programs, the smart phone not only provides communication function, but also serves as personal multimedia player, GPS, electronic books, electronic dictionary, and so on. The additional capabilities come with a price tag. As the new models of the smart phone cost more and more, the user often opts for placing a cover or sleeves over the smart phone for extra protection.
The most popular protective cover at present is of a wrapping structure, including a holding base and an upper lid. The holding base is for fixing the electronic device and the upper lid is flexibly connected to the side of the holding base so as to cover the holding base when flipped to protect over the case and the screen of the electronic device from scratching. However, when the electronic device wrapped with a protective cover is to be used in a car, e.g., as a GPS, the electronic device must be separated from the protective cover to avoid the upper lid from accidentally covering the screen, which causes inconvenience of using the electronic device in different environments.
In addition, the protective cover does not usually provide function of support. To place the electronic device in a tilt position for viewing, an extra support apparatus must be used. In other words, the conventional protective cover provides limited capability and, thus, a multi-functional protective cover is desirable.
SUMMARY OF THE INVENTION
The primary object of the present invention is to provide a multi-functional protective cover, with capability including protection from scratching, sunray-shielding, supporting, and so on, wherein the sunray-shielding being for using inside a car and the supporting is to support the electronic device to stand in a tilt position.
To achieve the above object, the present invention a protective cover, including a carrier unit and a protective lid. The carrier unit includes a first surface and a second surface, disposed oppositely. The first surface is for fixing and holding an electronic device. The protective lid is foldable in segments, with one side engaged to the second surface of the carrier unit, and the other side covering the first surface when folded. The protective lid is engaged to the second surface by an engaging means, and includes a first lid piece, a second connection piece, a third lid piece, a fourth connection piece and a fifth lid piece. The main feature is that the first lid piece is wider than the fifth lid piece, the fifth lid piece has a width wider than or equal to the width of the third lid piece, and the fourth connection piece is flexible. When folded, an edge of the fifth lid piece contacts the second connection piece.
Another embodiment of the present invention provides a protective cover, able to protect and shield. The protective cover includes: a carrier unit and a protective lid. The carrier unit includes a first surface and a second surface, disposed oppositely. The first surface is for fixing and holding an electronic device. The protective lid is foldable in segments, with one side engaged to the second surface of the carrier unit, and the other side covering the first surface when folded. The protective lid is engaged to the second surface by an engaging means, and includes a first lid piece, a second connection piece, a third lid piece, a fourth lid piece and a fifth lid piece. The main feature is that the total width of the fifth lid piece and the fourth connection piece is wider than the width of the third lid piece, the total width of the fifth lid piece and the fourth connection piece is less than the total width of the third lid piece and the second connection piece, and the fourth lid piece is flexible. When folded, an edge of the fifth lid piece contacts the second connection piece.
When the protective cover of the present invention is engaged to an electronic device, the basic function is to protect the surface of the device. Therefore, the third lid piece and the fifth lid piece will attach to the surface of the screen of the device to protect from scratching. For sunray-shielding, the fourth connection piece is folded so that the third lid piece and the fifth lid piece are pressed against each other, and placed to a device holder inside the car. When the device holder holds the electronic device, the fifth lid piece is also held tightly on the side of the electronic device, serving as a sunray-shielding visor on the side of the electronic device to facilitate easy viewing.
The protective cover of the present invention can also be used as a support stand. Following the predefined folding, the fifth lid piece is attached to the second surface of the carrier unit and the protective lid partially becomes a hollow triangular stand of a long strip shape. As such, the electronic device can stand in a tilt angle on a flat surface, such as, a desktop. At least two tilt angles are provided for using in various situations. Because the fifth lid piece has a width less than the width of the first lid piece. When folded in a specific manner, the reactive force of the third lid piece will apply to the second surface to further stabilize the structure.
The foregoing and other objects, features, aspects and advantages of the present invention will become better understood from a careful reading of a detailed description provided herein below with appropriate reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention can be understood in more detail by reading the subsequent detailed description in conjunction with the examples and references made to the accompanying drawings, wherein:
FIG. 1 shows a schematic view of the present invention in an unfolded state;
FIG. 2 shows a schematic view of the present invention in a folded state;
FIG. 3 shows a side view of the dissected structure of the present invention;
FIG. 4A shows a schematic view of the first actual application of the present invention;
FIG. 4B shows a side view of actual application of the present invention;
FIG. 5 shows a schematic view of the second actual application of the present invention;
FIG. 6 shows a schematic view of the third actual application of the present invention; and
FIG. 7 shows a schematic view of the second actual application of the present invention standing in different position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 , FIG. 2 and FIG. 3 are schematic views of the present invention in an unfolded state, folded state and dissected side view. The protection cover of the present invention includes a carrier unit 1 and a protective lid 2 .
The carrier unit 1 has a rectangular hard shape, with a first surface 11 and a second surface 12 disposed oppositely. The first surface 11 is for fixing and holding an electronic device. The means of fixing can be by gluing the back of the electronic device to the first surface 11 or disposing matching buckling elements respectively on the first surface 11 and the electronic device so that the matching buckle elements can be buckled together. However, the present invention does not impose any specific restriction on the fixing means. In the present embodiment, the carrier unit 1 is further disposed with a plurality of clippers 13 , distributed on the peripheral surrounding of the first surface 11 and extending upwards. The area formed by the plurality of clippers 13 matches the shape of the electronic device to be fixed and held. In the embodiment, four clippers are included and are located at the four corners of the first surface 11 . However, the present invention does not impose any specific restriction on the number and the distribution of the clippers. The number of clippers 13 can be two, located on two sides of the first surface 11 .
The protective lid 2 can be folded, with one side engaged to the second surface 12 of the carrier unit 1 . When folded, the other side of the protective lid 2 will cover the first surface 11 (as shown in FIG. 2 ). The protective lid 2 is engaged to the second surface 12 through an engaging means 20 , and includes a first lid piece 21 , a second connection piece 22 , a third lid piece 23 , a fourth connection piece 24 and a fifth lid piece 25 . In addition to protection, the present invention also provides functions of shielding and supporting. Therefore, specific restrictions on the width of the component pieces must be placed, including: the first lid piece 21 is wider than the fifth lid piece 25 , the fifth lid piece 25 has a width wider than or equal to the width of the third lid piece 23 , and the fourth connection piece 24 is flexible. When folded, an edge of the fifth lid piece 25 contacts the second connection piece 22 .
When folded, the protective cover 1 of the present invention has a shape similar to the mathematic symbol “belong to”. As shown in FIG. 4 , the carrier unit 1 provides fixing to an electronic device 5 . The protective lid 2 has only the engaging means 20 attached to the second surface 12 and the other components are not fixed. Therefore, a folded line exists between the engaging means 20 and the first lid piece 21 so that the first lid piece 21 can be lifted. In addition, the engaging means 20 does not exceed half of the area of second surface 21 . The engaging means 20 can be a small segment of flexible material. When assembled, the engaging means 20 is directly attached to the second surface 12 . The first lid piece 21 can be attached to the second surface 12 . The second connection element 22 is made of a flexible material or partially made of a hard material. The width of the second connection piece 22 must be equal to or greater than the thickness of the electronic device 5 . In the present embodiment, when the second connection piece 22 is partially made of a hard material, the joint between the second connection piece 22 and the first lid piece 21 and the joint between the second connection piece 22 and the third lid piece 23 must be foldable. Furthermore, the total width of the third lid piece 23 and the fifth lid piece 25 must be equal to or greater than the width of the electronic device 5 so as to provide protection to the surface of the electronic device 5 .
As shown in FIG. 3 , given that the width of the first lid piece 21 is D 1 , the width of the second connection piece 22 is D 2 , the width of the third lid piece 23 is D 3 , the width of the fourth connection piece 24 is D 4 and the width of the fifth lid piece is D 5 , and the width of the carrier unit 1 is S 1 . For the present invention to provide shielding and supporting, the basic requirement of the present invention is D 5 ≧D 3 and D 1 ≧D 5 . For preferred shielding effect, the total width of the fifth lid piece 25 and the fourth connection piece 24 must be less than the total width of the third lid piece 23 and the second connection piece 22 . In other words, (D 5 +D 4 )<(D 3 +D 2 ). For only shielding, the total width of the fifth lid piece 25 and the fourth connection piece 24 must be less than the width of the third lid piece 23 , i.e., (D 5 +D 4 )>D 3 , and the total width of the fifth lid piece 25 and the fourth connection piece 24 must be less than the total width of the third lid piece 23 and the second connection piece 22 , i.e., (D 5 +D 4 )<(D 3 +D 2 ). In actual application as shown in FIG. 5 , because the fourth connection piece 24 is flexible, the third lid piece 23 and the fifth lid piece 25 can be pressed against each other when folded. The edge of the fifth lid piece 25 extends to the second connection piece 22 . The fifth lid piece 25 will be close to or contact the side wall of the electronic device 5 . When the electronic device 5 is to be clamped by a device holder (arrow A indicating the direction of clamping), the fifth lid piece 25 and the third lid piece 23 are also clamped so that the fifth lid piece 25 forms a shielding visor located at the top edge of the electronic device 5 .
FIG. 6 and FIG. 7 show the views of the present invention applied as a supporting stand. The width of the first lid piece 21 of the present invention is greater than ¼ of the width of the carrier unit 1 , i.e., D 1 >(¼)S 1 . In a preferred embodiment, the width of the first lid piece 21 is greater than ½ of the width of the carrier unit 1 , i.e., D 1 >(½)S 1 . The total width of the fifth lid piece 25 and the fourth connection piece 24 is less than the width of the first lid piece 21 , i.e., (D 5 +D 4 )<D 1 . When used as a supporting stand, the protective cover of the present invention uses the carrier unit 1 to fix the electronic device 5 , folds the second connection piece 24 and the fourth connection piece 24 properly so that the fifth lid piece 25 is attached to the second surface 12 of the carrier unit 1 , and adjust the positions of the first lid piece 21 , the third lid piece 23 and the fifth lid piece 25 so that the three lid pieces form a hollow triangular stand of a long rectangle shape. As such, the electronic device 5 can stand with a tilt angle. In the present embodiment, the electronic device 5 can stand in two different angles. As shown in FIG. 6 , the protective cover uses the edge of the carrier unit 1 and the second connection piece 22 to contact the surface to be placed on. At this point, the tilt angle of the electronic device 5 is less than 45°. Because the width of the fifth lid piece 25 is less than the width of the first lid piece 21 , the reactive force of the third lid piece 23 is applied to the second surface 12 of the carrier unit 1 so that the structure is more stable. As shown in FIG. 7 , the protective cover uses the third lid piece 23 to contact the surface to be placed on. At this point, the tilt angle of the electronic device 5 is more than 60° and close to 90°. As such, the possible angles can be used for the electronic device 5 to stand on to facilitate convenient viewing of the screen.
Although the present invention has been described with reference to the preferred embodiments, it will be understood that the invention is not limited to the details described thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims. | A protective cover is provided, including a carrier unit and a protective lid. The carrier unit is for fixing an electronic device. The protective lid is foldable in segments, with one side engaged to the second surface of the carrier unit, and the other side covering the first surface when folded. When folded, the protective lid forms a shape able to shield or support. As such, the electronic device can be clamped by a device holder with taking off the protective cover, and the protective cover provides further capabilities of shielding form sunray and supporting to stand on a flat surface for convenient viewing. | 7 |
This is a division, of application Ser. No. 654,443, filed Feb. 2, 1976, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to optically coupled isolators, also known as optocouplers, photon couplers, and optoisolators. In particular, this invention relates to a structure for, and a method of manufacture of, an improved optically coupled isolator having relatively high electrical isolation.
2. Description of the Prior Art
Optically coupled isolators consist of two electronic circuits coupled together optically, rather than electrically. Electronic signals are transmitted across an isolation barrier between the two circuits by light, or photons, rather than by electrons. Typically, the isolator comprises a semiconductor emitter, such as a light-emitting diode, in the first circuit and arranged so that its light strikes a semiconductor photon detector, such as a phototransistor, in the second circuit. A transparent insulation fills the space between the emitter and detector, providing electrical isolation. Gallium-arsenide infrared emitters are often used because their 900-nanometer wave-length output falls near the maximum spectral response of the commonly used silicon phototransistor. As both the emitter and detector comprise semiconductors, the isolator is manufactured using standard semiconductor processing techniques, is relatively small in size, and is usually sealed in a small, standard size package.
Some applications for isolators include those where it is desirable to isolate electrically one circuit from another, such as in medical instrumentation. Other applications include those in which it is desirable to transmit an electronic signal between circuits while eliminating noise within the signal, such as in computers and other kinds of switching functions.
The level of applied voltage that can be handled by an isolator without electrical connection between circuits occurring is a function of the distance between the emitter and detector, and a function of the dielectric strength of the transparent insulator located in the space between the detector and emitter. With the need to manufacture isolators economically through the use of standard size packages, such as the small dual-inline package, one is limited in the length of the space available between the detector and emitter. Moreover, if the space becomes too long, the isolator would lose efficiency because of the loss of light energy between the emitter and detector, caused by diffraction, diffusion, reflection, and so forth. Typically, the detector surface facing the emitter is larger than the emitter surface facing the detector in order to ensure that more light will reach the detector. Consequently, for a given length of space between the emitter and detector, the dielectric strength of the insulator in the space determines the isolator's ability to withstand high levels of applied voltage and still maintain electrical isolation. Previously, various kinds of insulation material have been used in the space between the emitter and detector, for example, plastic film such as mylar, and plastic resins such as silicone and epoxy, all of which transmit up to about 95 percent or more of the applied light, and are suitable for semiconductor processing techniques. The typical dielectric strength of many of these materials is on the order of about 500 volts per mil, providing isolators capable of withstanding applied voltages of 2,500 to 3,500 volts. In order to increase the level of applied voltages that the isolator can withstand, it is desirable that the transparent insulation material in the space have a dielectric strength in the range of 1,000 volts per mil, or more, about twice that of the above-mentioned materials.
An insulation material that could be used in the space between the emitter and detector is glass, which transmits up to about 98 percent or more of the applied light and has high dielectric strength, such as on the order of 1,000 volts per mil. Unfortunately, glass is relatively rigid and difficult to process easily using standard semiconductor processing techniques for assembly of the isolators. Moreover, some type of special structure is necessary to support the glass firmly in place in the space between the emitter and detector, and to maintain the desired alignment during subsequent assembly and system use, particularly when sudden jolts or vigorous vibrations occur. Previously, one of several known metalization procedures has been used to provide areas on the glass that can be attached to some kind of a frame in the isolator. Metalization requires steps of deposition and chemical etching, often requiring the use of various chemicals, such as acids. Such chemical treatment can contaminate the glass, so that when the latter reaches a temperature of around 80° F., residual metallic ions, such as sodium, are able to migrate from the glass surface into the detector which is in direct contact with the glass, rendering the detector incapable of functioning effectively in an isolator. Moreover, even if it were possible to thoroughly clean the glass surface of foreign ions by extensive rinsing in deionized water after the etching step, alkali ions present to some degree in any glass would be free to migrate into the detector structure under the influence of temperature and electric field, because of the direct contact between the glass and the detector.
Therefore, an improved structure, and method of making the structure, is needed wherein the transparent insulation material in the space between the emitter and the detector is of a relatively high dielectric strength, and is also compatible with standard semiconductor processing techniques so that the cost of manufacturing the isolator is not substantially increased.
BRIEF DESCRIPTION OF THE INVENTION
The device according to the invention overcomes the above-mentioned disadvantages of prior-art isolators in that it uses insulation materials in the space between the emitter and detector of the isolator that provide a relatively high dielectric strength, provide for protection from migrating alkali ions, and allow the use of standard semiconductor processing techniques for assembly, so that the cost of manufacturing individual isolators is not substantially increased.
Briefly, the device comprises a pair of sets of metal interconnect leads with a semiconductor photoemitter attached to a lead in one of the sets of leads and a semiconductor photodetector attached to a lead in the other set of leads. A portion of one set of leads overlaps a portion of the other set of leads to enable the emitter and detector to face each other while leaving a space therebetween. In the space between the emitter and detector is a layer of clear glass held firmly in place by two or more layers of transparent junction coat material.
Briefly, the method of forming the improved isolator of the invention comprises the steps of forming a pair of sets of leads, attaching an emitter die to one lead in the first set of leads and a photodetector die to one lead in the second set of leads; connecting wires between each die and other leads in the set in which the die is attached; applying a first layer of junction coat material over the exposed portion of the detector die including locations where wires are connected to the die; heating the junction coat material until it hardens; applying a second layer of junction coat material over the first layer; placing a layer of glass over the second layer; heating the second layer until it hardens; placing the second set of leads with emitter attached over the glass but spaced apart therefrom, with the emitter and detector aligned so that they face each other; filling the space between the glass and the emitter with a third layer of junction coat material; heating the third layer until it hardens; and applying moulding compound around the structure to encapsulate it.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 through 8 are simplified cross-sectional drawings of the isolator during steps of its assembly.
FIGS. 9 through 11 are simplified two dimensional views of intermediate steps of the assembly of the isolator, showing a lead frame with a wire connected to an emitter in FIG. 9, to a detector in FIG. 10, and a glass over the detector in FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The method of assembly of an improved optically coupled isolator capable of withstanding relatively high voltage stresses applied thereto comprises a series of steps illustrated by FIGS. 1 through 8, and 9 through 11. First, two sets of leads are selected, such as the sets of leads 5 through 7 and 10 through 12 in the respective lead frames 1 and 2 of FIGS. 9 and 10. During assembly, the lead frames 1 and 2 provide support for the leads 5 through 7 and 10 through 12. Later, the leads are detached from frames 1 and 2. Preferably, the leads are of an electrically conductive material having a low thermal coefficient of expansion, such as about 5×10 -6 inches per inch per degree centigrade. Suitably, the leads comprise a material such as Alloy 42 or Kovar, or an equivalent, and are about ten mils thick. A thin gold layer is deposited on a portion of the lead where the semiconductor die is to be attached and on portions of the other leads where the interconnect wires to the die are to be attached.
During formation of the lead frames, each of the outer portions of the leads, such as outer portion 13 of lead 10 (see FIGS. 1 and 10), is depressed below the general level of the frame itself by about twenty mils. This difference in elevation enables the two sets of leads, 5 through 7 and 10 through 12, to be aligned, one set over the other set, during a subsequent step.
Referring to FIG. 9, the emitter die 8 is attached to the outer portion of lead 5 on frame 1, suitably using a combination of gold and germanium preform melted at a temperature of around 360° C. Referring to FIGS. 2 and 10, the detector die 15 is attached to the outer portion 13 of lead 10 in the set of leads 10 through 12 of frame 2. During attachment, a layer of silicon-gold eutectic, already present on the back of the die, is remelted, allowing gold from the lead to enter the melt, forming a strong intermetallic bond upon subsequent freezing. It will be appreciated that both die 8 and die 15 are attached to portions of the leads that are depressed about twenty mils below the frame elevation.
Electrical interconnections to the other leads in the set are provided by attaching small wires, 9 and 16, about 1.1 mils in diameter to pads on the respective die 8 and 15, using thermo-compression ball bonding techniques, and then to adjacent leads in a set, such as lead 6 on frame 1 and leads 11 and 12 on frame 2. Suitably, the pads comprise aluminum.
Referring to FIG. 4, a first layer 17 of transparent junction coat material, such as R6101 silicone resin, manufactured by Dow Corning Corporation, or an equivalent, is applied over the exposed surface of the detector die 15. Preferably, layer 17 is capable of transmitting 95 percent or more of the light applied thereto, has a relatively high thermal coefficient of expansion, such as about 80×10 -6 inches per inch degree centigrade, and has low alkali ion content. First layer 17 covers any ball bonds, such as ball bond 18, on the surface of detector die 15, and suitably is about three mils thick. The thickness of first layer 17 is grreater by one to two orders of magnitude than the typical thickness of a passivation layer over the principal surface of the detector die, which in the case of a silicon phototransistor, is silicon dioxide one micron thick. The first layer is then heated to approximately 150° C. for thirty minutes to allow it to harden.
Referring to FIG. 5, a second layer 20 of the junction coat material with characteristics similar to the first layer 17 is applied over the first layer that covers the principal surface of the detector 15. Suitably, the second layer 20 is about five mils thick.
While the second layer 20 is still in a fluid state, a layer of glass 22 is placed on the second layer 20 of junction coat material as shown in FIGS. 6 and 11. The glass layer is longer and wider than the detector die 15 and, for example, its dimensions are about 200 mils long, about 100 mils wide, and approximately 6 mils thick. Preferably, glass layer 22 has a relatively high dielectric strength, such as about 1,000 volts per mil or more, and transmits 98 percent or more of the light applied to it. Suitably, glass layer 22 comprises Corning type 0211 made by Dow Corning Corporation, or an equivalent. After glass layer 22 is placed over the second layer 20, the latter is heated to approximately 150° C. for about thirty minutes to allow the second layer 20 to harden and, in effect, lock the glass layer 22 in place. Layers 17 and 20 have a combined thickness of about eight mils, and function to keep the glass layer 22 away from the thin passivation layer of silicon dioxide, for example, over the principal surface of the detector die. This combined thickness inhibits and delays any alkali ions in the glass layer from reaching the detector die and detrimentally affecting its operating characteristics.
The frame 2 (see FIG. 10) with the set of leads containing the detector die 15 attached thereto and the glass layer 22 is placed on a welding fixture, with the detector die 15 facing in an upward direction. The frame 1 (see FIG. 9) with the set of leads having the emitter die 8 attached thereto is next rotated by about 180 degrees so that the emitter die 8 faces in a downward direction. Referring to FIG. 7, the two sets of leads are then positioned so that the emitter die 8 faces the detector die 15 across a space 25 therebetween.
Referring to FIG. 8, a third layer 30 of junction coat material is inserted between the glass 22 and the emitter die 8. Suitably, the third layer 30 comprises the same kind of material as was used for the first and second layers 17 and 20. The third layer 30 is heated to about 150° C. for about thirty minutes until it hardens. The combination of the first and second layers 17 and 20 of junction coat material and the third layer 30 of the same material work in cooperation when hardened to hold the glass layer 22 firmly in place at the desired alignment between the emitter die 8 and detector die 15, thereby ensuring good resistance to vibration and shock during subsequent assembly steps, and during use in electronic systems.
The assembly is next encapsulated using transfer moulding techniques in order to provide environmental protection. Preferably, the moulding compound 32 selected has a low thermal coefficient of expansion, such as in the range of 30×10 -6 inches per inch per degree centigrade. Suitably, the compound 32 consists of DC-308 made by Dow Corning, MC-506 made by General Electric, or an equivalent. Preferably the thermal coefficient of expansion of the moulding compound 32 and of the leads 5 through 7 and 10 through 12 is less than that of the junction coat material used in the first, second, and third layers 17, 20, and 30. During subsequent assembly steps, the frames 1 and 2 are removed from the leads 5 through 7 and 10 through 11 by the use of cropping and crimping dies.
The steps of assembling the optically coupled isolator incorporates known semiconductor processing techniques and does not substantially increase the assembly cost. Use of a layer of glass with a high dielectric strength enables isolation voltages to be in the range of 5,000 to 8,000 volts, without electrical connection between the emitter and detector occurring. Moreover, the junction coat material used to cover both die and to hold the glass layer firmly in place eliminates the need for special metalization, which can cause unwanted contamination of the glass. Also, the combined thickness of the first two layers of junction coat material, which have low alkali ion content, inhibit and delay migration of alkali ions, such as sodium, from the glass layer to the detector and unwanted subsequent deterioration from occuring in the detector's operating characteristics, Furthermore, the length of the space between the emitter and detector has not changed, enabling the assembly to fit easily into standard size semiconductor dual in-line packages. In addition, the glass does not touch the detector or the emitter so that the ball bonds on each are not damaged nor destroyed. | An improved optically coupled isolator uses a glass layer in combination with layers of junction coat material between the emitter and detector to provide greater electrical isolation while preventing potential ionic contamination in the glass from reaching the detector and causing a deterioration in its operating characteristics. The isolator is assembled using standard semiconductor processing techniques so that the cost of manufacture is not substantially increased. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to locking mechanisms and, more particularly, to those particularly suitable for use with sliding prison doors.
2. Description of the Prior Art
Known sliding prison door operating and locking mechanisms, typified by devices disclosed in U.S. Pat. Nos. 3,271,901, 3,426,478, and 3,564,772, are of complex design, and generally utilize vertical locking columns to provide secure and tamper-proof locking of sliding doors. Particularly because of their complexity, known prison door operating and locking mechanisms are not readily adaptable for use with stacking or overlapping prison doors.
SUMMARY OF THE INVENTION
The present invention provides a simple and inexpensive solution to this problem, and provides a novel door locking mechanism operable to insure deadlock engagement of a novel locking dog with a door-suspending carriage, obviating the need for complex locking systems, including those having locking columns. The present invention thereby provides a locking system which affords necessary security and tamper-free operation at a minimum cost.
The door locking mechanism of the present invention is adaptable for use with a prison door laterally movable across an opening defined by a doorway frame. The door locking mechanism generally comprises: a door-suspending carriage slidingly movable above the frame, the carriage having a transverse end latch plate; a rack bar; coupling means, preferably comprising a pressure pad assembly, for connecting the rack bar to the carriage and for providing limited relative movement therebetween; reversible rack bar drive means for moving the door between open and closed positions; a cam carried by the rack bar; a novel locking dog pivotally mounted to the doorway frame and having cam follower means for effecting pivotal locking dog movement between inner latched and outer unlatched positions in response to movement of the rack bar, the locking dog having a latch engageable with the latch plate when the locking dog is in its inner position to lockably restrain carriage movement; spring means for urging the locking dog into its inner position; and bumper means for blocking movement of the carriage beyond a predetermined position adjacent the locking dog and corresponding to door closure; the locking dog having a protruding arm engaged by the rack bar upon bar movement relative to the carriage when the carriage is in its door-closure position to insure deadlock rotation of the locking dog to its inner position.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view, with parts broken away and parts in section, of a pair of overlapping prison doors embodying the features of the present invention;
FIG. 2 is a top plan view, with parts broken away and parts in section, of a portion of the right-hand door shown in FIG. 1;
FIG. 3 is a front elevational view, with parts broken away and parts in section, of the locking mechanism shown in FIG. 2;
FIG. 4 is a top plan view, with parts broken away and parts in section, showing the details of the right-hand locking dog; and
FIG. 5 is a front elevational view, with parts broken away and parts in section, illustrating operation of the novel locking dog of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIG. 1, a pair of parallel known door-suspending carriages 10, 11 are provided for supporting associated doors below (not shown) by conventional hanger means extending through a pair of associated slots 12, 13 in doorway frames 14, 15. The door-suspending carriages 10, 11 are operable to slidingly move their respective doors from substantially coplanar door openings adjacent respective cell block wall portions 16, 17 into back-to-back overlapping or stacking relationship opposite a central support column 18, the overlapping arrangement providing well-known advantages of economy and space.
A pair of gear rack bars 19, 21 are independently driven by reversible drive means comprising electric motors 22, 23 having pinions in meshing relation with their associated rack bars to effect lateral sliding movement of their associated carriages 10, 11 by means of a first pair of grooved wheels 24 riding on track 25, and a second pair of grooved wheels 26 riding on track 27, respectively. A common release bar 28 is provided for unlocking both doors simultaneously in a manner to be described. A pair of identical left and right locking mechanisms, generally illustrated by reference numerals 29 and 31, are provided for securely engaging associated door-suspending carriages 10, 11 to lockably restrain movement thereof. Since the locking mechanisms 29 and 31 are identical, only the details of the right-hand mechanism 31 will be described.
As best seen in FIGS. 2 and 3, the doorway frame comprises a vertical support plate 32 to which can be connected a known horizontal protective cover (not shown) to define a housing for the right-hand door operating mechanism 31. Carriage 11 comprises a pair of parallel front and rear rectangular plates or bars 33, 34 (FIG. 2) joined at their right-hand end by an integral transverse or perpendicular end latch plate 35. A bumper plate 36 (FIGS. 2 and 3) is secured to latch plate 35 to engage a rubber bumper 37 (FIGS. 4 and 5) mounted within a housing 38 secured to as L-shaped bumper bracket 39 in turn connected to a flange 41 (FIG. 4) of a locking dog bracket 42 having another flange 43 suitably bolted to the frame member 32. The bumper 37 restrains rightward movement of the carriage 11 to a predetermined position which corresponds to full closure of the door suspended by that carriage.
With particular reference to FIG. 2, lost motion coupling means are provided for connecting gear rack bar 21 to carriage 11 and for providing limited relative movement therebetween. A coupling pad assembly 44 comprises an L-shaped bracket 45 having a vertical portion 46 thereof rigidly secured to rack 21 by means of bolts 47. Attached to a horizontal portion 48 of bracket 45 are a pair of coil springs 49 (below portion 48) guided by a pair of associated pins 51 to urge a vertically planar frictional pressure pad 52 into frictional engagement with bar 34 of carriage 11. When the rack bar 21 is moved laterally by motor 23, the pressure pad assembly 44 attempts to provide corresponding motion of the carriage 11. A bolt 53 (FIGS. 2 and 3) is situated within a hole 54 in bar 34 and slidably disposed within a horizontal slot 55 in rack bar 21, a retaining nut 56 being threaded onto bolt 53. Bolt 53 is operable to limit the relative movement of the rack bar 21 with respect to carriage 11. It will be appreciated that when the rack bar 21 and carriage 11 are moved rightward, upon engagement of the end plate 36 with bumper 37, the motion of the carriage 11 will be terminated, but the rack bar 21 will be moved a short distance rightward, equal to the width of slot 55, for a purpose to be described.
As best seen in FIGS. 3, 4 and 5, the prison door locking mechanism of the present invention includes a locking dog, generally illustrated by reference numeral 57, comprising an elongated body portion 58 integrally formed with a generally circular sleeve 59 (FIGS. 2 and 4) in turn suitably journaled to effect pivotal movement of body portion 58 in a vertical plane between an inner lower locking position (shown in FIG. 3) and an upper or outer position (shown in FIG. 5) about a pivot 61 (FIGS. 3 and 5) in turn secured to flange 41 of L-shaped bracket 42 by means of a nut 62 (FIG. 4). The outer end of locking dog 57 comprises a downwardly depending hook or latch portion 63 (FIG. 3) engageable with the latch plate 35 when the locking dog 57 is in its inner lower locking position to lockably restrain leftward movement of the carriage 11 and the door suspended thereby. A wire spring 64 (FIGS. 3 and 4) has ends 65, 66 for respective engagement with the body portion 58 of the locking dog 57 and the vertical portion 32 of the doorway frame, in order to urge the locking dog into its lower position.
As best seen in FIGS. 3 and 5, suitably secured to rack bar 21 is a trapezoidal-shaped cam 67 having a left-hand sloping face 68, a top horizontal face 69 and a right-hand sloping face 71. Cam 67 cooperates with cam follower means 72 (FIGS. 4 and 5) preferably comprising a roller suitably journaled for rotation about a pivot 73 secured to the body portion 58 of locking dog 57 by means of a nut 74 to effect pivotal locking dog movement between its lower and upper positions in response to movement of the rack bar 21.
It will be seen that as carriage 11 and rack bar 21 move simultaneously (through the agency of the previously described coupling means) rightward, as viewed in FIGS. 3 and 5, engagement between roller 72 and the right-hand face 71 of the cam 67 will cause the locking dog 57 to pivot upwardly, enabling a left cam face 75 of latch 63 to engage the upper right-hand corner of latch plate 35 to effect further upward movement of locking dog 57. Continued rightward movement will cause a lower flat portion 76 of latch 63 to engage the top surface of latch plate 35 until an inner surface 77 of latch 63 engages an inner sloping surface 78 in the end latch plate 35, thereby enabling the locking dog 57 to rotate downwardly through the agency of spring 64 to its FIG. 3 position. In its inner lower locked position illustrated in FIG. 3, the flat surface 77 of the latch 63 engages the left-hand surface of latch plate 35, with the result that movement of the door carriage 11 leftward will be prevented.
As best seen in FIGS. 4 and 5, locking dog 57 has a rearwardly protruding arm 79 secured to the sleeve 59 by means of a downwardly depending lever 81 (FIG. 5). The right-hand surface of bar 21 has a notched surface 82 (FIGS. 3 and 5) engageable with the arm 79 upon rightward relative movement between rack bar 21 and carriage 11, when restrained by bumper 37, in order to move arm 79 rightward, thereby forcing locking dog 57 to pivot into its FIG. 3 locked position should spring 64 fail to operate. Thus, deadlock rotation of the locking door 57 to its lower locked position is insured.
It will be appreciated that leftward movement of rack bar 21, normally by means of motor 23, will be necessary to initiate unlocking of locking dog 57. With reference to FIG. 3, initial leftward movement of the rack bar 21 will cause the roller 72 to engage the left-hand surface 68 of cam 67 to effect clockwise rotation of the locking dog 57, causing latch 63 to move upwardly. Further leftward movement of the rack bar 21 will first cause surface 77 of latch 63 to engage the sloping surface 78, and then cause the lower surface 76 of the latch 63 to ride on the upper horizontal surface of the end latch plate 35 (as shown in FIG. 3). Thereafter, additional leftward movement of the rack bar 21 will allow the locking dog 57 to drop out of engagement with the latch plate 35. The rack bar 21 will move relative to the carriage 11 until the latch 63 of the locking dog 57 releases the latch plate 35, at which point the pressure pad assembly 44 will effect simultaneous movement of the rack bar 21 and the carriage 11.
Should failure of motor 23 occur, known means are provided for effecting unlocking of the locking dog 57 to enable manual carriage movement leftward. As best seen in FIG. 3, a known socket 83 is provided within a bevel gear 84 suitably journaled for rotation about a horizontal axis and engageable with a gear 85 (FIGS. 2 and 3) in turn connected to an arm 86 pivotally connected to release bar 28 at pivot 87 through suitable linkage. Gear 85 is connected to a lower sleeve 88 suitably journaled for rotation about an inner shaft 89 (FIG. 3) in a known manner and having a lower arm 91 (FIGS. 2 and 3) engageable with notch 82 in bar 21. It will be apparent that rotation of sleeve 88 will cause the release bar 28 to move rightward from its FIG. 2 position and cause arm 91 to move leftward to engage notch 82 of the bar 21, thereby resulting in initial leftward movement of the bar to effect rotation of the locking dog 57 from its locked position. The release bar 28 also serves to simultaneously release the left-hand locking mechanism 29, thereby unlocking both doors. Once the locking dog in each of the locking mechanisms 29 and 31 are released, the doors can be opened manually.
It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it is apparent that various changes may be made in the form, construction and arrangement of its component parts without departing from the spirit and scope of the invention or sacrificing all its material advantages, the form described being mereby a preferred embodiment thereof. | A prison door locking mechanism particularly suitable for use with each of a pair of sliding prison doors laterally movable into stacking or overlapping position. The door locking mechanism includes a novel pivotally mounted locking dog having a latch engageable with a door-suspending carriage to lockably restrain carriage movement. The locking dog includes a projecting arm engaged by a rack bar coupled to the carriage to insure deadlock rotation of the locking dog to its locking position. | 4 |
BACKGROUND
[0001] A typical brush has a body from which extends a plurality of bristles. There is also often a handle that is either formed integrally with the body, or is screwed into the body using mating threads. The threads are disposed on an end of the handle, and in a cavity in the body.
[0002] The chief advantages of a screw coupling are reduced manufacturing cost, and convenient replacement of the handle. Handles having a screw coupling of handle and body are thus often used for long-handle brushes such as brooms, mops, where the item is fairly inexpensive, and there is considerable advantage in manufacturing, shipping, storing and displaying brush bodies separately from the brush handles.
[0003] In any event, the amount to which the handle is screwed into the body will almost certainly vary over time. This is especially true where the handle is screwed in and out for storage or replacement. In known brushes this is not a problem, because the handles are substantially linear, and radially symmetrical. Thus, the handle operates the same with respect to the body of the brush regardless of rotation of the handle; it makes no difference which “side” of the handle is facing up, and which “side” is facing down. The term “side” is used here in quotes because in theory a radially symmetrical handle has only one side. Nevertheless, there will always be slight differences in any physical embodiment of a handle, and the term “side” or “sides” in that context refers to a hypothetical longitudinal division of the handle into upper and lower portions.
[0004] Brushes with curved handles are also known, particularly where the curvature is intended to provide an ergonomic benefit. In such cases the handles are typically contiguous with the body, or at least permanently affixed to the body, since a fixed arrangement maintains a desired relationship between the curvature and the bristles.
[0005] A fixed arrangement between body and curved handle can be undesirable, however, in that the handle/body orientation cannot be adapted to different uses. For example, a user cannot switch a brush having a fixes handle from a concave down handle orientation to a concave up handle orientation, while maintaining the bristles in a down orientation.
[0006] The present applicant does not know of any brushes in which the orientation of a curved handle relative to the bristles can be changed by moving the handle from one cavity to another, or by flipping the handle about a pivot so that the handle extends from a different side of the brush. But even if those products do exist, they do not address a need for re-orientation of the curvature by rotation of the handle.
[0007] Thus, there is still a need for a brush having a curved handle, in which the orientation of the curvature can be changed by rotation of the handle.
SUMMARY OF THE INVENTION
[0008] The present invention provides apparatus, systems and methods in which a brush having an ergonomic handle can be utilized in conjunction with the body in different orientations as a result of rotation of the handle.
[0009] In preferred embodiments, the handle is readily removable from the body by the user, without the use of any tools. Release of the handle can be achieved in numerous ways, including the use of a spade shaped clip or other quick release mechanism. In especially preferred embodiments the handle has a terminal clip with two or more arms, each of which has a ridge or other detent that cooperates with a shoulder or other latching type of member in the receiving cavity. Contemplated bases have a mating mechanism, such as a round, oval, rectangular, slot shaped, or other receiving cavity.
[0010] In, another aspect the handle is ergonomic in having a curvature that fits in the palm of a user's hand, and/or an indentation for the user's thumb or one of his/her fingers. In cases where the handle is curved, the convex surface of the handle is considered to be the top, and the concave surface is considered to be the bottom. In such cases the top is preferably a mirror image of the bottom with respect to the indentations.
[0011] Brush bodies contemplated to be used in the inventive subject matter include numerous different shapes, with horizontal cross-sections being rectangular, round, oval, and so forth. The handle can be disposed with respect to the body in any suitable configuration, including where the handle is disposed substantially perpendicular to the longest dimension.
[0012] It is especially desirable to provide a collection of interchangeable brushes and handles, because a relatively small number of parts would provide numerous permutations that are well adapted to different uses. Thus, a system having 5 different brushes and 3 different handles would have 30 different permutations, including orientation changes as different permutations. It is further contemplated that the advantages of such a system of brushes could benefit from advertising that directs potential consumers to usefulness with respect to automotive care. One combination of brush and handle may be especially advantageous for cleaning wheel rims, while another combination may b especially advantageous for cleaning the hood.
[0013] Various objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components.
BRIEF DESCRIPTION OF THE DRAWING
[0014] FIG. 1A is a top view of a brush having an oval body and a medium length handle.
[0015] FIG. 1B is a side view of the brush of FIG. 1A with the handle in a first orientation.
[0016] FIG. 1C is a side view of the brush of FIG. 1A with the handle in an alternative orientation.
[0017] FIG. 2A is a top view of a brush having an ovoid body and a medium length handle.
[0018] FIG. 2B is a side view of the brush of FIG. 2A with the handle in a first orientation.
[0019] FIG. 2C is a side view of the brush of FIG. 2A with the handle in an alternative orientation.
[0020] FIG. 3A is a top view of a brush having an oval body and a short length handle.
[0021] FIG. 3B is a side view of the brush of FIG. 3A with the handle in a first orientation.
[0022] FIG. 3C is a side view of the brush of FIG. 3A with the handle in an alternative orientation.
[0023] FIG. 4A is a side view of a medium length handle detached from a brush body.
[0024] FIG. 4B is a top view of the brush of FIG. 4A with the handle in a first orientation.
[0025] FIG. 5 is a side view of a telescoping handle having a quick release mechanism.
[0026] FIG. 6 is a side view of a short handle having a quick release mechanism.
[0027] FIG. 7 is a cross-section of a connecting member of a preferred quick release mechanism, taken through 6 - 6 of FIG. 6 .
[0028] FIG. 8 is a side view of the base of FIGS. 3A, 3B , and 3 C, showing the slot that receives the connecting member.
DETAILED DESCRIPTION
[0029] FIGS. 1A and 1B depict a brush 10 having a body 12 from which bristles 14 extend, and a medium length handle 16 . Although shown more clearly in FIGS. 7 and 8 , the body 12 and handle 16 are coupled by a quick release mechanism that holds the handle 16 in a fixed orientation while it is inserted into the body, but allows the handle to be removed and reinserted into the body in an alternative orientation, FIG. 1C . Handle 16 has a slight curvature 16 A near the proximal end, and relative to that curvature has a top surface 16 B and a bottom surface 16 C. In the orientation of FIG. 1B the top surface 16 B is facing up, whereas in the orientation of FIG. 1C the top surface is facing down. Handle 16 also has a peg hole 16 D for hanging storage, and side indentations 16 E used for operating the quick release mechanism.
[0030] The brush body 10 , bristles 12 and handle 16 can all be made from any suitable material or materials, including plastics, rubbers, wood, metal, and so forth. For automotive use, the preferred material for the body 10 and handle is a hard plastic.
[0031] The dimensions are also contemplated to fall within any suitable limits. In a preferred embodiment, for example, body 12 measures approximately 25 cm long by 12 cm wide by 5 cm high. All ranges described herein are deemed to be inclusive of their endpoints.
[0032] FIGS. 2A, 2B and 2 C depict an alternative brush 20 , having an ovoid body 22 from which bristles 24 extend, and in this permutation the handle 16 depicted in FIGS. 1A, 1B , and 1 C. Although it is contemplated that different brush bodies in a collection of brushes could be made to couple with only certain handles, it is preferred that all bases and brushes in a collection would have interchangeable bodies and handles.
[0033] FIGS. 3A, 3B and 3 C depict another alternative brush 30 , in this case having an oval body 32 from which bristles 34 extend, and a short handle 36 depicted. Handle 36 is preferably interchangeable with handle 16 in terms of its coupling with multiple bodies. As with FIG. 1 , handle 36 has a slight curvature 36 A near the proximal end, and relative to that curvature has a top surface 36 B and a bottom surface 36 C. In the orientation of FIG. 3B the top surface 36 B is facing up, whereas in the orientation of FIG. 3C the top surface is facing down. Handle 36 has hanging hole 36 D.
[0034] FIGS. 4A , and 4 B depict yet another alternative handle 46 , which is preferably interchangeable with handle 16 in terms of its coupling with multiple bodies. As with FIG. 1 , handle 46 has a slight curvature 46 A near the proximal end, and relative to that curvature has a top surface 46 B and a bottom surface 46 C. In the orientation of FIG. 4B the top surface 46 B is facing up, whereas in an alternative orientation (not shown) the top surface would be facing down. Handle 46 has hanging hole 46 D, and finger indentations 46 E.
[0035] The male portion 48 of a quick connect mechanism extends from one end of the handle 46 . Portion 48 includes detents 48 A, which are operated by squeeze areas 46 F, which are normally biased in the directions of arrows 48 B.
[0036] In FIG. 5 an alternative handle 50 has three main pieces 56 A, 56 B, and 56 C that cooperate in a telescoping manner to increase or reduce the effective length of the handle 50 . Other telescoping handles are contemplated having more than two telescoping pieces. Handle 50 is not curved, but does form an angle 51 with the male portion 58 a quick release mechanism such that the handle 50 will extend from any of bodies 12 , 22 , 32 , or 42 at two different orientations, depending on whether the acute angle 51 is facing up or down.
[0037] FIG. 6 shows a side view of short handle 36 , separated from a base to depict the male portion 38 of a quick release mechanism. In FIG. 7 the male portion 38 is removed from the handle 36 to show a generally spade shaped piece with two 38 A, which are biased apart from each other sufficiently to cooperate with indentations 72 in a slot or other cavity 70 in one of the bodies 12 , 22 , 32 , or 42 to temporarily lock the handle to the body. To operate the release mechanism, a user pushes together the at indentations 36 F on the handle 30 , which in turn pushes together the sides 38 C of the spade shaped piece so that the detents 62 B clear the indentations 72 in a slot or other cavity 70 . FIG. 8 shows the corresponding slot or other cavity 70 , and the indentations 72 in outline.
[0038] In use, a user simply selects an appropriate handle, positions the handle either upside up or upside down, and then inserts the quick connect end of the handle into the receiving slot or other mechanism of the brush body. To remove, the user pushes in on the sides of the connection fork, or otherwise operates the quick-release mechanism, then pulls the handle away from the body. To place the brush in an alternate configuration, the user rotates the handle 180° along its long axis, and then re-inserts the connection end of the handle into the brush body.
[0039] Those skilled in the art will appreciate that instead of or in addition to removing a handle from a brush body, rotating the handle or body relative to one another, and then reinserting the handle, there are other ways to rotate the handle to achieve the same effect. For example, there may be a rotatable joint in the handle near its connection with the brush body. Such a joint could be locked in a given position using any suitable mechanism. In all such instances it is still contemplated that a brush having an ergonomic handle would have different orientations as a result of rotation of the handle, as those terms are used in this application.
[0040] Thus, specific embodiments and applications of brushes with rotating reversible handles have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. | A brush having an ergonomic handle is utilized in conjunction with a body in different orientations as a result of rotation of the handle. Suitable handles are readily removed from the body by the user by operating a spade shaped clip or other quick release mechanism. It is especially desirable to provide a collection of interchangeable brushes and handles that provide numerous permutations for different uses. It is further contemplated that the advantages of such a system of brushes could benefit from advertising that directs potential consumers to usefulness with respect to automotive care. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to a process for the prevention or restriction of oil spills.
[0002] More in particular the invention relates to a process for the prevention or restriction of oil spills on the water surface of seas, rivers or canals after accidents with oil tankers.
BACKGROUND OF THE INVENTION
[0003] Large marine calamities after accidents with large crude oil tankers, such as the oil tankers Prestige in November 2003 near Gibraltar and Exxon Valdez in Alaska in 1989 have made clear that the integral environmental damages, caused by large oil spills, can be immense and after initial cleaning of the contaminated areas, wildlife along the coast, and more in particular marine life, needs decades for restoration, if any.
[0004] Although several measures have been taken by governmental organizations of several major countries to reduce the risks of oil spills after accidents with ships in vulnerable sea water areas, such as the phasing out single hulled tankers by 201D in US waters, said accidents with oil tankers can never be excluded due to the expected increase of cargo ship traffic.
[0005] Moreover, there are still found intentional dumpings of waste oil by ships, the sizes of which can also cause large damages to coast and marine life.
[0006] It is known that the oil spills are normally eliminated only very slowly by natural processes. As oil spreads over the sea surface, natural processes start to break it down. More in particular the following physical and chemical changes will normally help the contaminated sea or ocean clean itself of oil:
evaporation of light substances of the water surface, emulsification by wave action, mixing the oil and water into a mousse-like substance which can be scooped up, dissolution of a low proportion of oil compounds into the seawater, heavy oil fractions are pulled down by the seafloor by sinking gravity, oxygen molecules combine with oil, allowing it to slowly dissolve in water, microbes in (sea)water feed on compounds in oil, breaking it down into water soluble compounds (biodegradation), after microbes have begun degrading oil, small worms join in. These worms are eaten by fish and the oil enters the marine food chain.
[0014] It will be appreciated that in order to prevent huge environmental and economical damages in the event of accidents in which oil tankers are involved, extensive research efforts have been made in the last decades and will be continued. In this respect several proposals have been made such as the dissemination of chemical emulsifying systems on the oil-contaminated sea water surfaces in order to disperse the oil for facilitating the oxidation and biodegradation of the oil or to coagulate the oil film on the water into relatively large droplets, which easily sink to the bottom.
[0015] An object of the present invention is to provide improved means for reduction of prevention of oil spills which moreover are immediately present ready for use on the spot at an economically attractive price.
[0016] It has now been found that particles, comprising a block copolymer having at least one predominantly poly(vinyl aromatic compound) block and at least one predominantly poly(conjugated diene) block, can quickly adsorb mineral oils and in particular a variety of crude oils, up to a large extent of their original weight, under formation of stable gels, even if the initial viscosity of such mineral oils is low, when added into or being present in or around oil containing compartments of a ship.
SUMMARY OF THE INVENTION
[0017] Accordingly, the present invention relates to a process for the prevention or restriction of oil spills of mineral oil and more in particular crude oil, by introduction of ready for use particles of block copolymer, comprising at least one predominantly poly(vinyl aromatic compound) block and at least one predominantly poly(conjugated diene) block into or around the relevant oil containing compartments in a ship.
[0018] It will be appreciated that the subsequent fast gelation of the oil/polymer combination will prevent leakage or further leakage of oil from the ship as any large oil volumes in said ship will be immobilized.
[0019] According to one embodiment of the process, particles of the block copolymers, stored permanently as packages on several convenient places on a ship, can easily be introduced into a damaged compartment of a ship such as cargo tanks or the bunker fuel tank, in order to immobilize the oil contents by forming a gel in order to prevent leakage.
[0020] More in particular, said permanently stored packages of block copolymer particles can be quickly introduced into the bunker oil tank and/or oil cargo tanks by means of a propelling gas, which is released in case of an emergency and which entrains the block copolymer particles into the tank(s).
[0021] According to another embodiment of the process said particles of block copolymer have been permanently incorporated into the double hull space in order to prevent leakage of oil from a damaged cargo tank and/or fuel tank.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The block copolymer to be used in the process of the present invention may be any block copolymer, comprising at least one predominantly poly(vinyl aromatic compound) block, having a weight average molecular weight of at least 10,000 and preferably from 10,000 to 45,000, and at least one predominantly poly(conjugated diene) block, having a weight average molecular weight of at least 30,000 and preferably from 50,000 to 300,000.
[0023] Preferred block copolymers are those having the formulae: A-B, A-B-A or (A-B) n X or mixtures thereof, wherein A represents a predominantly poly(vinyl aromatic compound) block, wherein B represents a predominantly poly(conjugated diene) block and wherein X represents the remainder of a coupling agent and wherein n is an integer in the range of from 2 to 14 and preferably from 2 to 8. With the term “predominantly poly(vinyl aromatic compound) block” or “predominantly poly(conjugated diene) block”, as used throughout the present specification and claims is meant that these blocks may have been prepared from major amounts of a main monomer, which optionally may be mixed with minor amounts of other comonomers (at most 10 wt %, relative to the total weight of monomers).
[0024] The poly(vinyl aromatic compound) blocks can be derived from styrene, o-methyl styrene, p-methyl styrene, p-tert-butyl styrene, 2,4-dimethyl styrene, alpha-methyl styrene, vinyl naphthalene, vinyl toluene, vinyl xylene, or mixtures thereof.
[0025] A preferred vinyl aromatic monomer is styrene as substantially pure monomer (content more than 99 wt % of the monomer mass) or as main monomer, mixed with minor proportions (at most 10 wt %) of one or more of other structurally related vinyl aromatic monomer(s) or with minor proportions of another comonomer (e.g. conjugated diene). The use of substantially pure styrene is most preferred.
[0026] The conjugated diene monomer can be selected from butadiene, isoprene, 2,3-dimethyl 1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene and mixtures thereof. Preferred conjugated diene monomers are butadiene or isoprene or mixtures thereof. Said mixtures of butadiene and isoprene can be copolymerized into a polymer block (B), comprising individual homopolymer blocks of poly(butadiene) and poly(isoprene) or a sole substantially random copolymerized block, having average homopolymer lengths of less than 100 monomer units and preferably of less than 20 monomer units.
[0027] A more preferred conjugated diene comonomer is butadiene or isoprene, which can be used as substantially pure comonomer alone (content more than 99 wt % of the monomer mass) or as main monomer, mixed with minor proportions (at most 51 wt %, relative to the weight of the total monomer mass) of one or more of the hereinbefore structurally related conjugated dienes or with minor proportions of a vinyl aromatic comonomer, such as styrene.
[0028] Most preferred block copolymers contain conjugated diene blocks, derived from substantially pure butadiene or isoprene.
[0029] The block copolymers may be either linear or radial and will preferably have an apparent total molecular weight in the range of from 100,000 to 650,000.
[0030] It will be appreciated that the main linear triblock copolymers or radial, multi-armed block copolymers may also comprise significant proportions of accompanying diblock copolymers, comprising the same poly(vinyl aromatic) block and poly(conjugated diene) block as in the respective (AB)-arms. Said diblocks result from the manufacture of the main triblock copolymer or radial block copolymer by coupling initially prepared living diblock copolymers with a coupling agent, as known from e.g. U.S. Pat. Nos. 3,231,635; 3,251,905; 3,390,207; 3,598,887 and 4,219,627 and EP patent applications nos. 0 413 294 A2; 0 387 671 A1; 0 636 654 A1 and WO 04/22931, the disclosure of which have been incorporated herein by reference.
[0031] The diblock content can be in the range of from 0 to 80 wt % and preferably from 10 to 50 wt %.
[0032] The 1,2-addition during the polymerization of conjugated diene and more preferably butadiene or isoprene (vinyl content) is preferably in the range of from 5 to 70 wt % and more preferably from 8 to 25 wt %.
[0033] Block copolymers to be used for the process of the present invention may show a bound vinyl aromatic monomer content in the range of from 10 to 50 wt % and more preferably from 20 to 40 wt %.
[0034] Examples of suitable block copolymers to be used according to the present invention are KRATON D-1118, KRATON D-1101, KRATON D-1102, KRATON D-1184, KRATON D-1186, KRATON D-1192, KRATON KX-220, KRATON KX-219 block copolymers or mixtures thereof (KRATON is a trade mark).
[0035] It will be appreciated that the block copolymer to be applied for the process of the present invention may also have been selectively hydrogenated, which means that the poly(conjugated diene) block(s) may have been fully or partially hydrogenated (residual ethylenical unsaturation less than 25%, preferably less than 5% of the original and more preferably less than 2% of the original ethylenical unsaturation, whereas the poly(vinyl aromatic) block(s) have not been substantially hydrogenated.
[0036] Such block copolymers are known from e.g. U.S. Pat. Nos. 3,113,986; 4,226,952; 5,039,755 and Reissue No. 27,145, the disclosures of which are herein incorporated by references.
[0037] Examples of said block copolymers are KRATON G-1652, G-1651, G-1654, G-1633 or G-6917.
[0038] The application of said selectively hydrogenated block copolymers is preferred and more in particular the application of KRATON G-1651 and G-1654.
[0039] It will be appreciated that the block copolymers to be used in the process of the present invention must have an active surface as large as possible and must occur therefore in the form of fine particles, obtainable by milling, and/or of a fluffy structure, obtainable by flashing off the solvent from the initially block copolymer containing cement.
[0040] Said block copolymers will normally be characterized by:
1. a bulk density of from 0.1 to 0.7 and preferably from 0.2 to 0.5; and 2. a particle size distribution such that the content of constituents remaining on a 5-mesh sieve is not greater than 30% by weight and the content of constituents passing through a 20-mesh sieve is not greater than 30% by weight or less.
[0043] According to a preferred embodiment of the present invention the applied block copolymers have a total pore volume of from 100 to 2000 mm 3 /g and preferably from 120 to 2000 mm 3 /g and more preferably from 150 to 2000 mm 3 /g.
[0044] Such block copolymers can be prepared according to e.g. U.S. Pat. No. 6,150,439 and more in particular column 7, lines 60-67, column 8, lines 10-15, column 9, lines 16-31.
[0045] It will be appreciated that in the applied block copolymer(s) one or more additives can be included, such as oleo chemical synthetic waxes and specifically those available under the designations SPRAY BUSTER™ and KEMESTER™ from WITCO CHEMICAL CORP. Said synthetic waxes are long chain polymers, principally of ethylene block copolymers, which are available in solid particulate or powder form. Said synthetic waxes can be included in small amounts of up to 5 wt % and preferably up to 2 wt %, relative to the weight of the block copolymer(s).
[0046] The invention also relates to ships in which the space around the hull of a bunker oil tank or tanks is filled up with the hereinbefore specified block copolymer particles and/or in which the double hull space around oil cargo compartments is filled with the hereinbefore specified block copolymer particles.
[0047] The invention also relates to ships wherein or whereon equipment has been installed, comprising at least one container, containing the block copolymer particles, for blowing said block copolymer particles in case of emergency into the bunker oil tank(s) and/or into the oil cargo tanks.
[0048] Preferably said equipment will comprise a container with propelling gas and connected there with a container with the block copolymer particles, and a connecting pipe between both containers, wherein a valve has been installed which can be automatically opened by a hard shock and/or by high temperatures, due to a local fire, where after the propelling gas together with entrained block copolymer particles is led into the bunker oil tank(s) or oil cargo tanks.
[0049] It will be appreciated that the present invention also relates to a ship, which has been significantly damaged and from which oil leakage has been prevented by an immobilized gel, formed by absorption of oil by the hereinbefore specified block copolymers. | The invention relates to a process for preventing or restricting oil spills from oil tankers. The process comprises application of block copolymer particles having a high active surface in the form of fine particles or a fluffy structure. The block copolymer has at least one predominantly poly(vinyl aromatic compound) block and at least one predominantly poly(conjugated diene) block. The process may comprise introduction of the block copolymer into damaged compartments of the ship and permanent placement of the block copolymer in the double hull space of the ship. The process may further comprise automatic introduction of the block copolymer upon detection of a hard shock or high temperatures. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of PCT application No. PCT/EP2008/063365, entitled “TRANSPORT BELT AND METHOD FOR THE PRODUCTION THEREOF”, filed Oct. 7, 2008, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a belt for a machine for the production and treatment of a fibrous web, in particular a paper, cardboard or tissue machine, as well as to a method to manufacture said belt.
[0004] 2. Description of the Related Art
[0005] Belts are used in machinery for the production and treatment of a fibrous web for example in the press section in order to transport the fibrous web through the press nip and subsequently to a transfer location where the fibrous web is transferred to the following dryer section.
[0006] Belts generally comprise at least one polymer coating providing the paper side of the belt into which a load-bearing textile fabric is embedded.
[0007] The known transport- or process belts often tend to delaminate during operation. The polymer coating which extends from the paper side to the machine side of the belt was applied from both sides of the textile fabric which therefore has an interior interface at which the polymer coatings separate during operation due to flexing.
[0008] In addition, the known transport- and process belts have several coating segments arranged adjacent to each other in cross machine direction, each of which represent only a partial width of the total polymer coating and which together form the polymer coating. The hitherto known transport- or process belts often break at the contact points of the coating segments.
[0009] In view of the aforementioned disadvantages, what is needed in the art is improved belts, as well as improved methods for their manufacture.
SUMMARY OF THE INVENTION
[0010] According to a first aspect of the invention, the present invention provides a transport- or process belt for a machine for the production or treatment of a fibrous web, especially a paper, cardboard or tissue machine, which has a paper side and a machine side, as well as a polymer coating and which includes a load-bearing textile fabric; whereby the textile fabric has a first side facing the paper side and a second side facing the machine side; whereby the textile fabric is permeable and has a permeability of at least 300 cfm, preferably of at least 550 cfm, and the polymer coating extends integrally from the first side of the textile fabric through the openings in the textile fabric to the second side of the textile fabric.
[0011] Based on the fact that the textile fabric has a permeability of at least 300 cfm, a polymer coating extending integrally from the first side of the textile fabric through the openings of the textile fabric to the second side of the textile fabric can be formed. Therefore, delamination of the polymer coating is almost impossible. Integrally in this context is to be understood that, viewed in thickness direction of the polymer coating, no interface exists inside the polymer coating extending from the first side to the second side of the textile fabric as could for example develop if the polymer material is applied onto the textile fabric from both sides and then meeting somewhere inside the textile fabric structure, thus forming an interface.
[0012] According to a second aspect of the invention, the present invention provides a method for the manufacture of a transport or process belt for a machine for the production or treatment of a fibrous web, in particular a paper, cardboard or tissue machine, with a textile fabric and a polymer coating comprising the following steps:
a) Providing a textile and permeable fabric which, viewed in the designated cross machine direction of the belt has a defined width as well as a first side facing the provided paper side of the belt and a second side facing the provided machine side of the belt; b) Coating of the permeable textile fabric on a partial width with polymer material in a viscous state in order to provide a first formed coating segment; c) Coating of the permeable textile fabric on a partial width with polymer material in a viscous state in order to provide a subsequently formed coating segment which overlaps the initially formed coating segment in certain areas in machine cross direction; d) Causing a bond of the two coating segments in the overlap area; e) Converting the polymer material from the viscous state to a solid state.
[0018] By providing an overlap area of adjacent coating segments, their bond with each other is clearly improved.
[0019] According to a third and alternative and/or additional aspect of the invention, the present invention provides a method for the manufacture of a transport or process belt for a machine for the production or treatment of a fibrous web, in particular a paper, cardboard or tissue machine, comprising the following steps:
a) Providing a permeable textile fabric with a first and a second longitudinal edge, respectively extending in the designated machine direction of the belt; b) Coating of the textile fabric with polymer material in a viscous state by means of a coating apparatus, whereby only a partial width of the textile fabric is coated simultaneously with the viscous polymer material by means of the coating apparatus; c) Converting the polymer material from the viscous to a solid state, whereby the textile fabric is a continuous belt and the continuous textile fabric is moved in the designated machine direction of the belt and the coating apparatus is moved in the designated cross machine direction of the belt relative to each other so that after movement of the coating apparatus from the first to the second longitudinal edge of the textile fabric the polymer material which was applied onto the textile fabric in a helix-type path forms a polymer coating which totally covers the textile fabric.
[0023] The helix-type application of the polymer material upon the textile fabric creates a polymer coating which progresses uninterrupted in machine direction.
[0024] According to a fourth alternative and/or additional aspect of the invention, the present invention provides a method for the manufacture of a transport or process belt for a machine for the production or treatment of a fibrous web, in particular a paper, cardboard or tissue machine, by coating a permeable textile fabric with polymer material in a viscous state, whereby a gap shaped forming channel is formed through which the textile fabric is led, whereby the forming channel has a front and a back limiting area each extending parallel to the textile fabric and between which the textile fabric is guided, whereby a first forming belt is provided which provides one of the two limiting areas and which is moved in the same direction as the textile fabric and essentially at the same speed while the viscous polymer material is fed into the forming channel and is carried along by the textile fabric and the first forming belt. Thereafter the first forming belt is separated from the polymer material at the end of the forming channel, whereby the first forming belt in the area of one of its longitudinal edges—on the side facing the textile fabric—has an elevation extending parallel to the longitudinal edge of the forming belt which provides a laterally limiting area of the forming channel.
[0025] By providing a lateral limiting area of the forming channel through the forming belt, the width of the overlapping region of the adjacent coating segments can be defined. This allows for a defined control and improvement for bonding between the coated segments.
[0026] According to a fifth alternative and/or additional aspect of the invention, the present invention provides a method for the manufacture of a transport- or process belt for a machine for the production or treatment of a fibrous web, in particular a paper, cardboard or tissue machine, by coating a permeable textile fabric with polymer material in a viscous state, whereby a gap shaped forming channel is formed through which the textile fabric is led, whereby the forming channel has a front and a back limiting area each extending parallel to the textile fabric and between which the textile fabric is guided along a transport direction, whereby means are provided through which the textile fabric is held during coating with the viscous polymer material so that it causes no waves or wrinkles.
[0027] The means ensure that the textile fabric is centered in the polymer coating. It is further ensured that the textile fabric is evenly embedded in the polymer coating, thereby clearly increasing the dimensional stability of the finished transport or process belt.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
[0029] FIG. 1 shows a sectional view of an inventive transport or process belt along the machine direction of the belt;
[0030] FIG. 2 shows a repeat of the textile fabric of the belt illustrated in FIG. 1 ;
[0031] FIG. 3 shows a sectional view of the transport or process belt illustrated in FIG. 1 , along cross machine direction of the belt;
[0032] FIG. 4 shows a top view of a device to implement the inventive method for the manufacture of a belt as illustrated in FIG. 1 ;
[0033] FIG. 5 shows a side view of the device shown in FIG. 4 ;
[0034] FIGS. 6 a and 6 b shows the device from FIGS. 4 , 5 in the area of a forming belt at various steps in the manufacture of the belt illustrated in FIG. 1 ; and
[0035] FIG. 7 shows a top view of the device to implement the inventive method to manufacture a belt illustrated in FIG. 1 .
[0036] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
[0037] Referring now to the drawings, and more particularly to FIG. 1 , there is shown one design form of an inventive transport or process belt 1 in a sectional plane extending in machine direction (MD). Belt 1 has a paper side 2 and a machine side 3 . Belt 1 further includes a polymer coating 4 and a textile load-bearing fabric structure 5 . Textile fabric 5 has a first side 6 facing paper side 3 and a second side 7 facing machine side 3 .
[0038] Textile fabric 5 is permeable and has a permeability of at least 300 cfm, preferably at least 550 cfm. Polymer coating 4 extends integrally from the first side 6 of textile fabric 5 through openings 8 in textile fabric 5 to the second side 7 of the textile fabric 5 .
[0039] Hereby the polymer coating 4 is preferably produced—at least from the first side 6 to the second side 7 of textile fabric 5 —from a single polymer material. This embodiment provides a belt which has practically no tendency to delaminate.
[0040] In the current example polymer coating 4 extends in a single piece from paper side 2 of belt 1 to machine side 3 of belt 1 , and is produced preferably from a single polymer material from paper side 2 of belt 1 to machine side 3 of belt 1 .
[0041] Belt 1 can have an overall thickness in the range of approx. 2 mm to approx. 6 mm, whereby preferably the ratio of overall thickness of belt 1 to the thickness of the textile fabric 5 is in the range of 2:1 to 5:1.
[0042] The total width of the belt can be in the range of approx. 1 m to approx. 12 m.
[0043] The polymer material of the polymer coating exemplarily includes polyurethane. Advantageously the polymer material consists completely of polyurethane. In addition one or several filler(s) may be embedded into polymer coating 4 .
[0044] Textile fabric 5 has a center plane extending through the center of the thickness of textile fabric 5 which is indicated in the illustration in FIG. 1 by line M-M. Preferably the same amount of polymer material is applied on both sides of the center plane so that polymer coating 4 has a uniform thickness with respect to the center plane.
[0045] In addition, polymer coating 4 is preferably impermeable, so that consequently an impermeable belt 1 is provided.
[0046] Textile fabric 5 preferably has a permeability in the range of approx. 500 cfm to approx. 1200 cfm, preferably approx. 550 cfm to approx. 900 cfm.
[0047] Textile fabric 5 can be formed by itself or in combination with a woven fabric, a spiral wire or a yarn array. In the current example the textile fabric is provided by a woven fabric.
[0048] Textile fabric 5 comprises machine direction threads 9 and cross machine direction threads 10 , whereby cross machine direction threads 10 have a greater flexural strength in their longitudinal direction than the machine direction threads 9 in their longitudinal direction. Textile fabric 5 which represents the load-bearing structure of the belt hereby gains a very high flexural strength in cross machine direction (CMD) and thereby a high dimensional stability. The higher flexural strength of cross machine direction threads 10 as opposed to the flexural strength of the machine direction threads can be achieved for example in that the machine direction threads 9 in their cross section have a greater width than height, whereas the cross machine threads 10 in their cross section have a width which is equal to the height. The different flexural strength may however also be influenced or completely determined by the selection of the material or materials from which machine direction threads 9 and cross machine direction threads 10 are manufactured.
[0049] In the current design example textile fabric 5 is in the embodiment of a woven fabric 5 , meaning that machine direction threads 9 are interwoven with cross machine direction threads 10 , whereby in order to form woven fabric 5 machine direction threads 9 are more curved in their longitudinal progression than the cross machine direction threads 10 in their longitudinal progression.
[0050] Cross machine direction threads 10 progress preferably not curved in their longitudinal direction.
[0051] According to a preferred embodiment of the invention, woven fabric 5 comprises a repeat weaving pattern. FIG. 2 illustrates such a repeat pattern. The repeat preferably includes machine direction threads of a first type 9 . 2 , 9 . 3 which, on the first side 6 of textile fabric 5 , cross a first number of successive cross machine threads 10 . 4 - 10 . 6 , 10 . 8 - 10 . 2 , 10 . 2 - 10 . 4 , 10 . 6 - 10 . 8 , creating a flotation F, before they continuously cross a single cross machine thread 10 . 3 , 10 . 7 , 10 . 1 , 10 . 5 on the second side 7 of woven fabric 5 while creating a bend K.
[0052] For example the machine direction thread of the first type 9 . 2 floats on the first side 6 of woven fabric 5 continuously over the three successive cross machine direction threads 10 . 4 - 10 . 6 before it runs on the second side 7 of the woven fabric and forms a bend K over the cross machine direction thread 10 . 7 .
[0053] In addition, the repeat includes preferably machine direction threads of the second type 9 . 1 , 9 . 4 which continuously form a flotation F on the second side 7 of woven fabric 5 in that they cross a second number of successive cross machine direction threads 10 . 4 - 10 . 6 , 10 . 8 - 10 . 2 , 10 . 2 - 10 . 4 , 10 . 6 - 10 . 8 before they run on the first side 6 of the woven fabric 5 and cross a single cross machine direction thread 10 . 3 , 10 . 7 , 10 . 1 by forming a bend K. Flotation F in the current example is to be understood to mean that a machine direction thread running on one side of the woven fabric crosses more than two successive cross machine direction threads without interweaving with a cross machine thread on the side opposite to the one side. Bend K in the current example is to be understood to mean that one machine direction thread on one side of the woven fabric continuously crosses only one single cross machine thread, whereby the machine direction thread on the side opposite the one side continuously crosses the cross machine threads which are located before and after this single cross machine thread.
[0054] As can be seen in the illustration in FIG. 2 it is advantageous if a bend K is located between successive flotations F, and a flotation F is located between successive bends K.
[0055] As illustrated in FIG. 2 , the first number of successive cross machine direction threads may also be the same as the second number of successive cross machine direction threads. In the current example the first and the second number is three. However, the first number and/or the second number could also be two, four or five.
[0056] In the repeat of woven fabric 5 the machine direction threads 9 . 1 - 9 . 4 are arranged preferably in the following sequence:
a first machine direction thread of the second type 9 . 1 which is followed by a first machine direction thread of the first type 9 . 2 which is followed by a second machine direction thread of the first type 9 . 3 , which again is followed by a second machine direction thread of the second type 9 . 4 .
[0061] Within the repeat of the woven fabric
the first machine direction thread of the second type 9 . 1 advantageously forms flotations F and bends K with the cross machine direction threads with which also the first machine direction thread of the first type 9 . 2 forms flotations F and bends K, also the first machine direction thread of the first type 9 . 2 and the second machine direction thread of the first type 9 . 3 forms bends K with different cross machine direction threads, also the second machine direction thread of the first type 9 . 3 forms flotations F and bends K with the cross machine direction threads with which also the second machine direction thread of the second type 9 . 4 forms flotations F and bends K.
[0065] The first machine direction thread of the first type 9 . 2 of the repeat and the second machine direction thread of the first type 9 . 3 may preferably be offset to each other by one to four, especially two cross machine direction threads 10 . 4 , 10 . 5 .
[0066] FIG. 3 shows a cross section of inventive belt 1 in cross machine direction (CMD). In the illustration of FIG. 3 belt 1 is seen in a section between two adjacent cross machine threads 10 . This means, in the illustration in FIG. 3 no cross machine direction thread 10 of the textile fabric in the embodiment of woven fabric 5 is seen. It can however be clearly seen that the polymer coating 4 extends integrally from the first side 6 of textile fabric 5 through openings 8 of textile fabric 5 to the second side 7 of textile fabric 5 .
[0067] Viewed in cross machine direction CMD polymer coating 4 consists of several coating segments 4 a - 4 d extending across a partial width of belt 1 , whereby adjacent coating segments 4 a - 4 d overlap in an overlap region 11 a - 11 c . Coating segments 4 a - 4 d are connected with each other at least in sections in overlapping region 11 a - 11 c , whereby bonding is provided preferably through chemical cross linking of the polymer material which provides coating segments 4 a - 4 d.
[0068] As can be seen from FIG. 3 the overlap regions 11 a - 11 c of adjacent coating segments 4 a - 4 d are formed in that one coating segment 4 a - 4 d forms a tab 12 a - 12 c protruding laterally in cross machine direction and having a lesser thickness than the remaining coating segment 4 a - 4 d which engages in a conforming recess 13 b - 13 d of the adjacent coating segment 4 a - 4 d.
[0069] As can be seen, tabs 12 a - 12 c essentially have a thickness which is consistent with the thickness of the textile fabric. This may be achieved for example by the special process control as described in FIGS. 6 a and 6 b . The length of tabs 12 a - 12 c in CMD can be influenced for example during the production process by the viscosity of the polymer material.
[0070] Viewed in cross machine direction at least some of the coating segments—for example in the illustration in FIG. 3 coating segments 4 b and 4 c include a tab 12 b , 12 c on the one end side and a recess 13 b , 13 c on the other end side respectively. (Note: as a rule all coating segments comprise always one tab and one recess with the exception of the coating segments which determine a longitudinal edge of the belt).
[0071] For example, coating segment 4 a viewed in cross machine direction forms tab 12 a on the one end side which, in order to form the overlap region 11 a engages in the conforming recess 13 b of the adjacent coating segment 4 b.
[0072] In addition each coating segment 4 a - 4 d has an upper and a lower outside surface whereby the upper and/or lower outside surfaces of adjacent coating segments smoothly adjoin.
[0073] FIGS. 4 and 5 show a machine by which an inventive transport or process belt can be produced. FIG. 4 shows the machine and a partially coated textile fabric 5 in a top view. A preferably permeable textile fabric 5 in the form of a continuous belt is stretched over an open distance S between two parallel rolls 16 , 17 . Textile fabric 5 has a first and a second longitudinal edge 14 , 15 extending respectively in the designated machine direction MD of belt 1 .
[0074] In order to coat textile fabric 5 with polymer material in a viscous state a coating apparatus 18 is used by means of which only a partial width of textile fabric 5 can simultaneously be coated. During the coating process continuous textile fabric 5 is moved in the designated machine direction MD of belt 1 and coating apparatus 18 for the viscous polymer material is moved in the designated cross machine direction CMD of belt 1 relative to each other so that after a single movement of coating apparatus 18 from first longitudinal edge 14 to second longitudinal edge 15 of textile fabric 5 the polymer material is applied in a helix-type path 19 onto textile fabric 5 , and textile fabric 5 is completely covered with polymer coating 4 .
[0075] Transport direction T of textile fabric 5 through forming channel 20 described in FIGS. 5-7 is consistent with the superimposed position of the movement of coating apparatus 18 with the movement of textile fabric 5 .
[0076] In addition the coating apparatus includes a holding device 43 by means of which textile fabric 5 is held in position during coating with the viscous polymer material 22 so that no waves or wrinkles occur.
[0077] During application of the helix-type path, the adjacent path segments form coating segments 4 a - 4 d which are known from FIG. 3 , whereby adjacent coating segments 4 a - 4 d overlap respectively in an overlap region 11 a - 11 c . The solid line in FIG. 4 represents the contact edge between adjacent coating segments 4 a - 4 d on the paper side of coating 4 . The respective overlap region 11 a - 11 c extends then always from the solid line to the broken line nearest to it.
[0078] It would also be conceivable not to apply the polymer coating in form of an uninterrupted helix type path of viscous polymer material onto the textile fabric, but instead apply several self-contained polymer paths which are located adjacent to each other in cross machine direction.
[0079] FIG. 5 shows a side view of the machine for the production of inventive belt 1 .
[0080] Coating apparatus 18 is shown. Coating apparatus 18 comprises a forming channel 20 through which textile fabric 5 which at this stage is uncoated at least across a partial width is fed from above and which leaves forming channel 20 in a downward direction, and coated across a partial width. Coating apparatus 18 further comprises means 21 to feed viscous polymer material 21 into forming channel 20 .
[0081] As already explained the permeable textile fabric has a first side 6 facing the provided paper side and a second side 7 facing the provided machine side.
[0082] Viscous polymer material 22 may be applied from one of the two sides 6 , 7 onto the permeable textile fabric 5 . In the current example viscous polymer material 22 is applied from the first side 6 of the fabric which faces the paper side 2 of belt 1 . It is however also conceivable to apply viscous polymer material 22 from the second side 7 of the textile fabric which faces the provided machine side 3 of belt 1 .
[0083] Due to the fact that polymer material 22 is applied from one of the two sides 6 , 7 in a viscous state onto permeable textile fabric 5 so that it flows from the first side 6 of textile fabric 5 through openings 8 of textile fabric 5 to the second side 7 of textile fabric 5 , an integral coating 4 is created which extends from the first side 6 to the second side 7 of textile fabric 5 and which, in contrast to a polymer coating which was applied from two sides onto the textile fabric, has practically no tendency to delaminate.
[0084] Influencing factors to cause viscous polymer material 22 to flow from first side 6 to second side 7 of the textile fabric may for example be the permeability and the time required to solidify the viscous polymer material. The time in which polymer material 22 is in the viscous state, and the permeability of textile fabric 5 can be coordinated so that the viscous polymer material can flow from first side 6 of textile fabric 5 through openings 8 of textile fabric 5 to its second side 7 .
[0085] Polymer material 22 may for example have a viscosity in the range of 250 cps to 1000 cps when reaching the forming channel which enables the viscous polymer material to flow from first side 6 of textile fabric 5 through openings 8 of textile fabric 5 to the second side 7 .
[0086] The polymer material is advantageously solidified after approx. 10 s to 150 s, especially after approx. 10 s to approx. 50 s from the viscous state to a green state.
[0087] In its viscous state polymer material 22 comprises a hardener component and a pre-polymer component. The time for solidification of the viscous polymer material and thereby the viscosity is herewith influenced by the initial weight ratio between hardener and pre-polymer, whereby the initial weight ratio is the weight ratio between hardener and pre-polymer at the time of intermixing. The initial weight ratio includes preferably more hardener than polymer. The polymer material includes especially a duroplastic. Advantageously the polymer is a duroplastic.
[0088] The initial weight ratio includes for example between 55% and 80% hardener and between 45% and 20% pre-polymer.
[0089] Tests conducted by the applicant have shown that the textile fabric advantageously has a permeability of at least 300 cfm, preferably of at least 550 cfm and a maximum of 1200 cfm.
[0090] FIGS. 6 a and 6 b illustrate coating apparatus 18 in the area of gap-shaped forming channel 20 along section A-A. Forming channel 20 progresses vertically. Air entrapments in the polymer material during coating can thereby be avoided.
[0091] Forming channel 20 is limited on one side and in its thickness by two forming belts 23 and 24 .
[0092] As already explained, during coating of the permeable textile fabric with viscous polymer material 22 , the textile fabric 5 is guided through gap-shaped forming channel 20 . Forming channel 20 has a front limiting area 25 and a rear limiting area 26 which respectively extend in forming channel 20 parallel to textile fabric 5 and between which textile fabric 5 is guided. First forming belt 23 provides the front limiting surface 25 and moves in the same direction as textile fabric 5 , and essentially at the same speed, while viscous polymer material 22 is fed into forming channel 20 and is carried along by textile fabric 5 and first forming belt 23 . At the end of forming channel 20 the first forming belt 23 is separated from the polymer material. As can be seen in FIG. 6 , first forming belt 23 has an elevation 28 (in the illustration in FIG. 6 in the area of its left longitudinal edge 27 ) on its side facing textile fabric 5 and progressing parallel to longitudinal edge 27 of forming belt 23 and which provides a lateral limiting area 29 of forming channel 20 .
[0093] Second forming belt 24 represents the other of the two limiting areas—in the current example the rear limiting area 26 —of forming channel 20 , whereby second forming belt 24 in the area of one of its longitudinal edges 30 on the side facing textile fabric 5 has an elevation 31 progressing parallel to longitudinal edge 30 of second forming belt 24 and providing a lateral limiting area 32 to forming channel 20 .
[0094] Second forming belt 24 also moves in the same direction as textile fabric 5 and essentially at the same speed while viscous polymer material 22 is fed into forming channel 20 and is carried along by textile fabric 5 and second forming belt 24 . At the end of forming channel 20 the second forming belt 24 is separated from the polymer material 22 .
[0095] As can be seen in the illustration in FIG. 6 a , elevation 28 of first forming belt 23 and elevation 31 of second forming belt 24 laterally limits forming channel 20 on the same side 34 . In addition, a segment 33 of textile fabric 5 is run between the two elevations 28 , 31 .
[0096] In the current example textile fabric 5 is run in the area of the forming channel squeezed between elevation 28 of first forming belt 23 and elevation 31 of second forming belt 24 . Viewed in width direction of forming channel 20 (this is consistent with cross machine direction CMD) elevations 28 , 31 of the two forming belts 23 , 24 are located at the same height for this purpose.
[0097] In other words, elevation 28 of first forming belt 23 and elevation 31 of second forming belt 24 , viewed in width direction (CMD) of forming channel 20 , are located relative to each other so that the lateral limiting area 29 of first forming belt 23 is arranged as an extension to lateral limiting area 32 of second forming belt 24 .
[0098] Since the two elevations 28 , 31 have the same height, textile fabric 5 is run centered between front limiting area 25 and rear limiting area 26 . If the two elevations were to have a different height, textile fabric 5 would be run off-center between front limiting area 25 and rear limiting area 26 .
[0099] In addition, forming channel 20 has no lateral limiting areas on the other side 35 , located opposite the one side 34 .
[0100] In addition, textile fabric 5 is wider than the two forming belts 23 , 24 viewed in width direction CMD of forming channel 20 .
[0101] By means of the design and layout of the two forming belts 23 , 24 described above, a coated area with a defined thickness is formed in the area between front limiting area 25 and rear limiting area 26 of forming channel 20 during coating of textile fabric 5 with viscous polymer material 22 ; and in the area between the two elevations 28 and 31 of the first 23 and the second forming belt 24 facing each other a tab 12 with a lesser thickness is formed onto the coated area.
[0102] On its side facing away from forming channel 20 , first forming belt 23 and/or second forming belt 24 may be supported on an opposite surface 36 , 37 in a way that the two forming belts 23 , 24 are run at a defined distance from each other in the area of forming channel 20 (see FIG. 5 ).
[0103] Each of forming belts 23 , 24 is continuous and is guided around two guide rolls 42 whereby the respective opposite surface 36 , 37 in the area of forming channel 20 is located between the two guide rolls 42 .
[0104] In addition, on the side facing away from forming channel 20 , first forming belt 23 and/or second forming belt 24 can have an elevation/recess 38 , 39 progressing parallel to longitudinal edge 27 , 30 of forming belt 23 , 24 with which forming belt 23 , 24 is guided along a corresponding recess/elevation 40 , 41 in the opposite surface 36 , 37 (see FIG. 6 a ).
[0105] The direction of travel of both forming belts 23 , 24 preferably encompasses an angle of 0.01° to 15°, in particular between 0.2° and 2°, with the longitudinal or machine direction MD of textile fabric 5 . Both forming belts 23 , 24 move in their direction of travel at a speed in the range of approx. 0.25 m/min. to 1.5 m/min.
[0106] FIG. 6 b illustrates the subsequent steps in the manufacture of transport or process belt 1 .
[0107] After the permeable textile fabric has been coated on a partial width with viscous polymer material 22 , thus forming the initial coated segment 4 a (as shown in FIG. 6 a ), permeable textile fabric 5 is coated with the viscous polymer material on an additional partial width which partially overlaps the one partial width, thus forming the subsequent coated segment 4 b which overlaps the initially formed coated segment 4 a in one overlap area 11 a in cross machine direction CMD.
[0108] For this purpose forming channel 20 and textile fabric 5 are moved relative to each other in their position in cross machine direction, so that forming channel 20 is located, in segments, in a partial area of the textile fabric which has not yet been provided with a coating segment. Since in the current example the polymer coating is applied in a helix-type path, shifting of the offset of the forming channel relative to the textile fabric occurs continuously. As can be seen from the illustration in FIG. 6 b , forming channel 20 is limited on the one side 34 by two lateral limiting areas 29 , 32 of both forming belts 23 , 24 , whereas on the other side 35 forming channel 20 is limited laterally by coating segment 4 a which was produced immediately prior. Here the two forming belts 23 , 24 overlap the initially formed coated segment 4 a so that, on the one hand, they rest on this coated segment 4 a and, on the other hand provide forming channel 20 .
[0109] As already explained, the initially formed coated segment 4 a has a tab 12 a in the overlap area 11 a , protruding in cross machine direction CMD and the additional subsequently formed coated segment 4 b has a corresponding recess 13 b with which tab 12 a engages.
[0110] Subsequently in the method a bond between the two coated segments 4 a and 4 b is caused in overlap area 11 a.
[0111] As already explained in the description of FIGS. 4 and 5 the two adjacent partially wide coated segments 4 a and 4 b are formed in that the continuous textile fabric 5 is coated with polymer material 22 in a partial width path 19 which runs around textile fabric 5 in a continuous helix type pattern.
[0112] Immediately after application of polymer material 22 , a conversion from the viscous state to a solid state of polymer material 22 is caused. Here it is conceivable that the bond of the two coated segments 4 a and 4 b in overlap area 11 a and the conversion of polymer material 22 from the viscous state to a solid state can occur at least partially simultaneously.
[0113] The conversion of polymer material 22 from the viscous state to the solid state includes preferably cross-linking of polymer material 22 . In other words, a chemical cross-linking takes place. For this purpose the polymer material may in particular have a hardener component and a pre-polymer component which are intermixed immediately prior to the coating process, whereby cross-linking begins immediately after mixing of the two components.
[0114] In order to achieve a good and solid bond of coating segments 4 a , 4 b in overlap area 11 a it is especially advantageous if coating of textile fabric 5 with the polymer material when creating the subsequent coating segment 4 b occurs, as long as the polymer material of the initially formed coated segment 4 a is not yet completely cross-linked. It is preferable if the subsequent coated segment is produced while the polymer material of the initially formed coated segment 4 a remains in a green state.
[0115] Tests conducted by the applicant have shown that the ratio between hardener and pre-polymer is adjusted so that the duroplastic polymer material 22 solidifies after approx. 10 s to 150 s, especially after approx. 10 s to approx. 50 s, from the viscous state to a green state.
[0116] Tests conducted by the applicant have further shown that a permanent bond of the coated segments which partially overlap each other can be achieved especially when an additional coated segment 4 b is formed within 24 hours after a prior coated segment 4 a was formed.
[0117] In order to make the bond between adjacent coated segments, for example 4 a and 4 b , or 4 b and 4 c , very durable it can be advantageous to subject the polymer material of the initially formed coated segment in the area of tab 12 b , 12 c , 12 d to a thermal treatment, especially a heat treatment immediately prior to creating the subsequent coated segment.
[0118] As can be seen from the illustrations in FIGS. 3 and 6 b the respective tab 12 a , 12 b , 12 c extends essentially inside textile fabric 5 which, in the current example, can be achieved by the specific embodiment of the two forming belts 23 , 24 and their positioning relative to each other.
[0119] Tabs 12 a - 12 c essentially have a thickness which is consistent with the thickness of textile fabric 5 . This can be achieved for example by the specific process control, in other words in that textile fabric 5 is run between the two elevations 28 , 31 of the two forming belts 23 , 24 . The length of tabs 12 a - 12 c can be influenced, for example, through the viscosity of the polymer material during the manufacturing process.
[0120] Application of the polymer material is preferably conducted so that the tab of the coated segment which is produced first extends in cross machine direction between 10 mm and 50 mm, especially between 20 mm and 35 mm, into the recess of the subsequently formed coated segment.
[0121] The application of the polymer material is in addition conducted preferably so that the respective coated segments 4 a - 4 d extend in cross machine direction CMD between 100 mm and 500 mm, especially between 150 mm and 300 mm.
[0122] As can be seen from the illustration in FIG. 6 b , polymer coating 4 which is formed by the different coated segments preferably provides machine side 2 and/or paper side 3 of belt 1 .
[0123] In addition all coated segments 4 a - 4 d have preferably the same thickness, whereby the upper and/or the lower outside surfaces of adjacent coating segments 4 a - 4 d smoothly adjoin.
[0124] It can also be seen in the illustration in FIG. 6 b that polymer coating segments 4 a - 4 d extend at least in some regions from the first side 6 of textile fabric 5 through openings 8 of textile fabric 5 to the second side 7 of textile fabric 5 . Each of the coating segments 4 a - 4 d is integral.
[0125] FIG. 7 shows a simplified illustration of the device depicted in FIGS. 4-6 in the area of the two forming belts. It can be said generally that in the method for the manufacture of the transport or process belt by means of coating permeable textile fabric 5 with polymer material 22 in a viscous state, textile fabric 5 is run through the gap-shaped forming channel 20 , whereby forming channel 20 has a front limiting area 25 and a rear limiting area 26 which respectively extend parallel to textile fabric 5 and between which textile fabric 5 is guided along a transport direction (Note: in FIG. 7 the transport direction extends essentially vertically to the drawn plane; the transport direction results from superimposing of the movement of textile structure 5 in machine direction and cross-directional movement of coating apparatus 18 ).
[0126] In addition, means are provided by which textile fabric 5 is held in position during coating with the viscous polymer material so that it does not produce any waves or wrinkles. In the current example the means include a first and a second holding device 43 , 47 arranged at the height of forming channel 20 and having opposite surfaces 48 - 51 between which textile fabric 5 is squeezed.
[0127] The two holding devices 43 , 47 are located outside forming channel 20 .
[0128] Holding textile fabric 5 in position hereby includes stretching of textile fabric 5 in forming channel 20 , in cross direction to the transport direction.
[0129] As already explained, front limiting area 25 of forming channel 20 is provided by first forming belt 23 ; and rear limiting area 26 of forming channel 20 is provided by second forming belt 24 between which textile fabric 5 is guided. Here, the two forming belts 23 , 24 run in the same direction and essentially at the same speed as the textile fabric 5 .
[0130] First holding device 43 —viewed in cross direction to the transport direction—is located at a distance from the two forming belts 23 , 24 , whereby the distance between first holding device 43 and the two forming belts 23 , 24 is between 10 cm and 100 cm, preferably between 30 cm and 55 cm.
[0131] In the first holding device 43 the two opposite surfaces 48 , 49 are provided by a pair of rollers 44 , 45 which are rotatable in transport direction of the textile fabric.
[0132] Second holding device 47 is provided by the two elevations 28 , 31 of forming belts 23 , 24 which face toward textile fabric 5 and between which textile fabric 5 is squeezed and guided. In the second holding device 47 an offset of the two opposite surfaces 50 , 51 at cross direction to the transport direction is preferably avoided through appropriate means, thereby further avoiding creation of waves or folds in the textile fabric.
[0133] Textile fabric 5 is held by the two holding devices 43 , 47 in an area which has not yet been coated, whereby textile fabric 5 is coated in the second holding device 47 during the holding process and while a tab is formed.
[0134] Textile fabric 5 is held in position during the coating process by the two holding devices 43 , 47 so that a centered position of textile fabric 5 in the polymer coating 4 is ensured. In addition, occurrence of wrinkles or waves in textile fabric 5 is avoided during the coating process. Obviously, according to the invention only one of the two holding devices 43 , 47 may be provided. However, provision of both holding devices 43 , 47 provides an especially effective centering of textile fabric 5 , as well as effective avoidance of wrinkles and waves.
[0135] In the current example the two opposite surfaces are provided by a pair of rolls 44 , 45 which are rotatable in transport direction of textile fabric 5 , whereby in the current example each of the two opposite surfaces is rigidly connected with one of the two forming belts 23 , 24 .
[0136] While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | The invention relates to a transport or processing belt for a machine for the production or treatment of a fiber web, particularly a paper, cardboard or tissue machine, having a paper side and a conveying side and comprising a polymer coating and a textile load-bearing fabric, wherein the textile fabric has a first side facing the paper side and a second side facing the conveying side. The textile fabric is permeable with a permeability of at least 300 cfm, preferably of at least 500 cfm, and the polymer coating extends in one piece from the first side of the textile fabric though the openings of the textile fabric to the second side of the textile fabric. | 3 |
[0001] The present invention relates to a method and apparatus for masking a portion of a component and particularly, but not exclusively, to a method and apparatus which allows a plurality of components to be masked both quickly and accurately.
BACKGROUND
[0002] It is known to apply a Thermal Barrier Coating (TBC) to a surface of a component which operates at an elevated temperature. Thermal barrier coatings typically have low thermal conductivity, and therefore, in use, display a large temperature gradient across the thickness of the coating. Accordingly, thermal barrier coatings provide thermal insulation to components and thus allow the components to operate under large and prolonged heat loads. Furthermore, thermal barrier coatings may extend the life of the component by reducing oxidation and by reducing cyclic loading caused by temperature variations which may result in thermal fatigue.
[0003] Thermal barrier coatings are commonly applied to metallic components which are subjected to high-temperature conditions. For example, thermal barrier coatings are widely used within gas turbine engines, particularly on combustor rings, nozzle guide vanes, turbine blades, etc.
[0004] Thermal barrier coatings may be applied to a component using a number of techniques. For example, a thermal barrier coating may be applied using a physical vapour deposition technique (e.g. electron beam or laser beam deposition), direct vapour deposition, plasma spraying, electrostatic spray assisted vapour deposition, etc.
[0005] It is known to provide an interior surface of a circular combustor ring with a thermal barrier coating. To achieve this, the combustor ring is located within a TBC spray-chamber with the TBC spray nozzle located approximately at the centre of the circular combustor ring and in alignment with the interior surface. The TBC spray nozzle and combustor ring may be rotated relative to one another, such that the thermal barrier coating from the TBC spray nozzle covers the entire circumferential interior surface. This may be achieved by rotating the combustor ring using a rotary table or by rotating the TBC spray nozzle.
[0006] However, for the purposes of assembling the combustor a circumferential portion of the interior surface of the combustor ring is left uncoated. Accordingly, this portion of the interior surface is covered by a special adhesive TBC-proof tape, which masks the portion from the thermal barrier coating. The application and subsequent removal of the adhesive tape is carried out by hand and as a result is a slow and correspondingly expensive procedure. Furthermore, the current method is wasteful since the tape (approximately 5 m of tape per combustor ring) is discarded after every use.
[0007] The present invention seeks to overcome some or all of the problems associated with the prior art method described above.
STATEMENTS OF INVENTION
[0008] In accordance with an aspect of the invention there is provided a method of masking a portion of a component, the method comprising: attaching a sacrificial masking element to a locating jig; and disposing the locating jig against a surface of the component such that the sacrificial masking element is positioned over the portion of the component.
[0009] The sacrificial masking element may be attached to the locating jig by a sacrificial connector; and the method may further comprise: inserting a deformable portion of the sacrificial connector through the sacrificial masking element, wherein the deformable portion is in an unlocked position, and deforming the deformable portion from the unlocked position to a locked position to lock the sacrificial masking element to the locating jig.
[0010] The deformable portion may be a pair of legs which are bendable from the unlocked position to the locked position.
[0011] The method may further comprise stacking a second component on top of the locating jig.
[0012] Further components may be stacked on top of one another with a locating jig disposed between adjacent components. This may allow a coating to be applied to a plurality of components in a single operation. This may be particularly advantageous where the coating is applied in a vacuum chamber (e.g. for electron beam deposition), since the invention reduces the number of times the chamber must be evacuated.
[0013] The sacrificial masking element may also mask a portion of the second component.
[0014] The method may further comprise applying a coating to the component. The sacrificial masking element may prevent the coating from contacting the masked portion of the component.
[0015] The coating may be a thermal barrier coating.
[0016] In accordance with another aspect of the invention there is provided a masking apparatus, the apparatus comprising: a sacrificial masking element for masking a portion of a component; and a locating jig detachably connectable to the sacrificial masking element and configured to position the sacrificial masking element over the portion of the component.
[0017] The method and apparatus of the present invention may allow a portion of a component to be quickly and accurately masked. Furthermore, the present invention may reduce costs by using a sacrificial masking element which can be replaced without needing to replace the locating jig.
[0018] The locating jig may be detachably connectable to the sacrificial masking element via a sacrificial connector.
[0019] The locating jig may comprise a hole or slot for receiving the sacrificial connector.
[0020] The sacrificial connector may comprise a deformable portion which may be deformable from an unlocked position to a locked position to lock the sacrificial masking element to the locating jig.
[0021] This may allow the sacrificial masking element to be quickly and easily connected to and disconnected from the locating jig. The sacrificial connector may be deformed from the unlocked position to the locking position, and vice versa, by hand or using readily available tools.
[0022] The deformable portion may comprise a pair of legs which may be bendable between the unlocked position and locked position.
[0023] The locating jig may comprise a recess for receiving the sacrificial connector.
[0024] The recess may comprise a shoulder which abuts an end surface of a shoulder of the sacrificial connector. The shoulder of the recess may be gripped between the shoulder of the sacrificial connector and the sacrificial masking element when the sacrificial connector is in the locked position.
[0025] The sacrificial masking element may comprise a first layer and a second layer. The first layer may be disposed against the component and the second layer may be spaced away from the component by the first layer. The second layer may protrude over an edge of the first layer and thus may define the extent of the masked portion of the component.
[0026] This configuration may prevent a continuous film from forming between the second layer and the component which may otherwise cause the sacrificial masking element to become joined to the component.
[0027] The sacrificial masking element may be substantially perpendicular to the locating jig.
[0028] The locating jig and sacrificial masking element may be circular.
[0029] The locating jig may be formed from a plurality of arcuate sections.
[0030] This may allow individual arcuate sections to be replaced. Furthermore, the locating jig may be disassembled to reduce its size and may be assembled around the component where it is difficult to install the locating jig once it is fully assembled.
[0031] The locating jig may be formed from first and second layers of arcuate sections which may be rotated relative to one another and connected to one another.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:
[0033] FIG. 1 is a perspective view of a section of a masking apparatus in accordance with an embodiment of the invention prior to assembly;
[0034] FIG. 2 is an enlarged perspective view of a sacrificial connector of the masking assembly;
[0035] FIG. 3 is a perspective view of the masking apparatus during assembly;
[0036] FIG. 4 is a perspective view of the masking apparatus after assembly; and
[0037] FIG. 5 is a cross-sectional view of a stack of combustor rings during a thermal barrier coating operation, where a portion of each combustor ring is masked by the masking apparatus.
DETAILED DESCRIPTION
[0038] With reference to FIG. 1 , a masking apparatus 2 in accordance with an embodiment of the invention comprises a circular sacrificial masking element 4 , a circular locating jig 6 , and a plurality of sacrificial connectors 8 which detachably connect the sacrificial masking element 4 to the locating jig 6 .
[0039] The sacrificial masking element 4 is a circular ring of material having a plurality of circumferential slots 10 which pass through the sacrificial masking element 4 and are spaced around its circumference. The sacrificial masking element 4 is formed from an inner ring 5 a and an outer ring 5 b . The inner ring 5 a has a slightly smaller diameter than the outer ring 5 b . Furthermore, the inner ring 5 a is longer than the outer ring 5 b . The inner ring 5 a is received within the outer ring 5 b with the outer ring 5 b located at the axial centre of the inner ring 5 a . Accordingly, the inner ring 5 a projects either side of the outer ring 5 b and the inner and outer rings 5 a , 5 b contact one another (as shown in FIG. 5 ).
[0040] The locating jig 6 is formed from first and second locating rings 12 a , 12 b . The first and second locating rings 12 a , 12 b are in turn formed from a plurality of arcuate sections 14 . The arcuate sections 14 of the first locating ring 12 a are rotated relative to the arcuate sections 14 of the second locating ring 12 b , such that joints between adjacent arcuate sections 14 of the first locating ring 12 a are not aligned with the joints of the second locating ring 12 b . Adjacent arcuate sections 14 of the first locating ring 12 a are connected to one another by passing a connector, such as a pin, screw or rivet, through an adjacent end of each of the adjacent arcuate sections 14 and into the second locating ring 12 b . The connection of the adjacent arcuate sections 14 to the second locating ring 12 b locks the arcuate sections 14 together. Similarly, the arcuate sections 14 of the second locating ring 12 b are connected via the first locating ring 12 a using connectors 16 .
[0041] Each of the first and second locating rings 12 a , 12 b has a plurality of recesses 18 spaced around the circumference of the ring. As shown, each arcuate section 14 may have four recesses 18 formed in it. The recesses 18 of the first and second locating rings 12 a , 12 b are located so that when the first and second locating rings 12 a , 12 b are connected to one another using the connectors 16 , the recesses 18 of the first locating ring 12 a are aligned with the recesses 18 of the second locating ring 12 b.
[0042] The recesses 18 are shaped to receive the sacrificial connectors 8 . As shown in FIG. 2 , each sacrificial connector 8 comprises a pair of lateral shoulders 20 which protrude from each side of the sacrificial connector 8 . Each sacrificial connector 8 further comprises a pair of legs 22 extending from between the shoulders 20 . An indentation 24 is formed in each side of the recesses 18 . The indentations 24 are defined by a pair of shoulders 26 located at the opening to each recess 18 . The indentations 24 are complementary to the shoulders 20 of the sacrificial connectors 8 . In use, the shoulders 20 of the sacrificial connectors are received within the indentations 24 with an end surface 28 of each shoulder 20 abutting a respective shoulder 26 of the recess 18 .
[0043] As shown in FIG. 3 , the legs 22 of each sacrificial connector 8 are received through one of the slots 10 in the sacrificial masking element 4 with the legs in an unlocked position where they lie in the plane of the remainder of the sacrificial connector 8 . The legs 22 may then be deformed from the unlocked position to a locked position to connect the masking element to the locating jig 6 and to prevent disengagement. This is achieved by bending the legs 22 over towards the masking element 4 so that they no longer lie in both the plane of the remainder of the sacrificial connector 8 and the plane of the slots 10 of the sacrificial masking element 4 . As shown in FIG. 4 , one leg 22 may be bent downwards and the other leg 22 may be bent upwards. In doing so, the end surface 28 of each shoulder 20 of the sacrificial connector 8 is urged into contact with each shoulder 26 of the recess 18 . This locks the shoulder 26 of the recess 18 between the end surface 28 of the sacrificial connector 8 and the sacrificial masking element 4 . Consequently, the locating jig 6 is locked to the sacrificial connector 8 , which is in turn locked to the sacrificial masking element 4 . The legs 22 are preferably deformed by hand or using readily available tools, such as pliers.
[0044] In use, the masking apparatus 2 may be used to mask a portion of a component, such as a combustor ring 30 , from the application of a thermal barrier coating. The combustor ring 30 has a circular cross-section which has a widened portion at one end. Accordingly, the combustor ring 30 has a narrow end 32 and a wide end 34 . The combustor ring 30 has a circumferential portion 36 at both the narrow end 32 and wide end 34 which must remain uncoated.
[0045] As shown in FIG. 5 , a plurality of combustor rings 30 are stacked on top of one another. The combustor rings 30 are arranged so that adjacent combustor rings 30 have their like-ends adjacent to one another (i.e. the wide end 34 of one combustor ring 30 is adjacent to the wide end 34 of the next combustor ring 30 in the stack, and the narrow end 32 of one combustor ring 30 is adjacent to the narrow end 32 of the next combustor ring 30 in the stack).
[0046] A masking apparatus 2 is disposed between adjacent combustor rings 30 . The masking apparatus 2 is provided in two different diameters; one sized for masking the wide ends
[0000] 34 of adjacent combustor rings 30 and the other sized for masking the narrow ends 32 of adjacent combustor rings 30 . The outer ring 5 b of the sacrificial masking element 4 contacts the circumferential portion 36 of the adjacent combustor rings 30 which centralises the masking apparatus in the combustor rings 30 . Consequently, the inner ring 5 a is spaced away from the circumferential portion 36 and a gap is left between the inner ring 5 a and the circumferential portion 36 where the inner ring 5 a overhangs the outer ring 5 b . The locating jig 6 is sandwiched between radial surfaces of the adjacent combustor rings 30 which correctly aligns the masking apparatus 2 in an axial direction so that the inner ring 5 a fully covers the circumferential portion 36 which should remain uncoated.
[0047] A spray nozzle (not shown) is located at a centre of the combustor rings 30 and is translatable in an axial direction along a path 38 from the combustor ring 30 at the bottom of the stack to the combustor ring 30 at the top of the stack. The spray nozzle has a number of discrete positions 40 which are each aligned with one of the combustor rings 30 . In these positions 40 the spray nozzle can apply the thermal barrier coating to the combustor ring 30 over a region between the circumferential portion 36 at the narrow end 32 and the circumferential portion 36 at the wide end 34 . The stack of combustor rings 30 are located on a rotary table (not shown) and the spray nozzle sprays the thermal barrier coating onto the combustor rings 30 whilst they are being rotated by the rotary table. This ensures that the whole circumference of the combustor rings 30 is coated. This is repeated for each position 40 of the spray nozzle so as to coat every one of the combustor rings 30 .
[0048] The spray nozzle ejects a thermal barrier coating in a radial direction with little or no spread. Consequently, the inner ring 5 b of the sacrificial masking element 4 casts a shadow over the circumferential portion 36 . The sacrificial masking element 4 therefore prevents the thermal barrier coating from contacting the circumferential portion 36 .
[0049] Furthermore, as the outer ring 5 b spaces the inner ring 5 a away from the circumferential portion 36 , the coating does not create a continuous film between the inner ring 5 a and the combustor ring 30 , which would otherwise cause the sacrificial masking element 4 to become joined to the combustor ring 30 , thus hindering disassembly of the stack of combustor rings 30 .
[0050] Once all of the combustor rings 30 have been coated, they may be easily disassembled, simply by unstacking the combustor rings 30 and removing the masking apparatuses 2 . The sacrificial masking element 4 can then by disconnected from the locating jig 6 by bending the legs 22 of the sacrificial connectors 8 back from the locked position to the unlocked position where the legs 22 lie in the plane of the slots 10 of the sacrificial masking element 4 . This also releases the sacrificial connectors 8 from the locating jig 6 . The sacrificial masking element 4 and/or sacrificial connectors 8 may then be replaced before the next thermal barrier coating operation.
[0051] Although the masking apparatus 2 has been described with reference to combustor rings 30 , it may be used to mask other components. Such components are not limited to circular components. Accordingly, the sacrificial masking element 4 and locating jig 6 need not be circular, but instead may be appropriately configured for the component for which it is intended to mask.
[0052] Furthermore, it is not necessary for the masking apparatus 2 to be disposed between adjacent components. The locating jig 6 of the masking apparatus 2 may instead rest on a top or bottom surface of a single component. The weight of the component forces the locating jig 6 against the bottom surface. The locating jig 6 may be fixed to the top surface of the component using a weight or clamping arrangement to ensure that it does not move.
[0053] Although the inner ring 5 a has been described as overhanging the outer ring 5 b on either side, it may only overhang on one side of the outer ring 5 b . Furthermore, the inner ring 5 a need not be ring shaped and may instead be configured to mask the desired portion of the component. For example, where it is desired that the portion to be masked has a crenulated edge, the inner ring 5 a may have a correspondingly shaped edge to provide such a shadow over the component.
[0054] The sacrificial masking element 4 and sacrificial connectors 8 may be discarded after every thermal barrier coating operation or may be used for several separate operations. The sacrificial masking element 4 and sacrificial connectors 8 are intended to be replaced more frequently that the locating jig 6 .
[0055] The masking apparatus 2 is not limited to providing a mask from a thermal barrier coating, as described above. The masking apparatus 2 may mask a component from other coatings which are sprayed, such as paint. Furthermore, the masking apparatus 2 could be used as a sacrificial beam stopper in electron beam welding or laser trimming operations. The sacrificial masking element 4 may be formed from a material which is suitable for the intended purpose of the masking apparatus 2 . For example, where the sacrificial masking element 4 is used as a beam stopper, it may be made from iron and have an appropriate thickness to prevent the beam from penetrating through the sacrificial masking element 4 . | A method and apparatus ( 2 ) for masking a portion ( 36 ) of a component ( 30 ), the apparatus ( 2 ) comprising: a sacrificial masking element ( 4 ) for masking the portion ( 36 ); and a locating jig ( 6 ) detachably connectable to the sacrificial masking element ( 4 ) and configured to position the sacrificial masking element ( 4 ) over the portion ( 36 ) of the component ( 30 ). | 8 |
This application is a continuation of application Ser. No. 08/534,056 filed Sep. 29, 1995, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to hot melt adhesive compositions useful for waterproofing stitched seams and a method of using the same. This invention particularly relates to certain hot melt adhesives which can be directly applied to a stitched seam such that the resulting seam is resistant to water penetration.
In the manufacture of waterproof articles such as rainwear, workwear, tents and shoes; several methods are known in the art for waterproofing stitched seams.
GB 2 215 660 A teaches covering a stitched seam with a tape of thermoplastic material fused by hot air or pressure. A tape is made by solvent casting a 20 to 40 percent by weight polyurethane solution onto a release sheet. The coated sheet is then slit and wound onto a reel. The tape can be applied to the garment using machinery known for applying tapes having heat-activated adhesives.
Liukko U.S. Pat. No. 4,604,152 and Emrich et al., U.S. Pat. No. 4,605,578 also pertain to methods of making a waterproof stitched seam using a heat-activated thermoadhesive material.
In general, and particularly in the shoe industry, the use of solvent cements or waterbased emulsions to seal the stitched seams in shoes and boots are widely used. This is very time consuming and labor intensive as multiple coating and drying steps are employed. Seams sealed in this manner are not generally durable and a high percentage of shoes and boots manufactured are sometimes returned due to water leakage complaints.
It is therefore desirable to employ a hot melt type adhesive, that can be readily applied to form a good reliable water-proofed seam. It is especially desirable to use a hot melt adhesive that is not heat-activated.
SUMMARY OF THE INVENTION
This invention relates to novel hot melt adhesive compositions and methods of using the same to manufacture waterproof stitched seams in the manufacturing of water-proof articles. The adhesives of the present invention can be applied directly to a stitched seam with any suitable known hot melt application equipment without first premanufacturing a tape. Preferably, the hot melt adhesive of the present invention is applied as a continuous bead to a stitched seam. Such application may be done by hand, with the aid of robotics, or with any other known automated hot melt application equipment. Upon cooling, the adhesive forms a non-tacky flexible seal over the stitched seam that exhibits excellent resistance to water penetration and remains flexible over a wide temperature range. The use of a hot melt has the distinct advantage of eliminating the need for solvents, which are necessarily undesirable because of environmental concerns and health risks to workers. Furthermore, directly coating a hot melt adhesive onto a stitched seam is more economical, less time consuming, and can actually result in superior seam performance relative to prior application methods that employed solvent types of adhesives.
The hot melt adhesive composition useful in the present invention comprises:
a) from about 5 to about 40% percent by weight of a substantially linear A-B-A block copolymer, wherein A is polystyrene and B is a substantially saturated rubbery midblock comprising ethylene/butylene, ethylene/propylene and mixtures thereof;
b) an amount up to about 15% by weight of a substantially A-B diblock copolymer wherein A is polystyrene and B is a rubbery block comprising isoprene, ethylene/butylene, ethylene/propylene, butadiene and mixtures thereof;
c) an amount up to about 20% by weight of a tackifying resin;
d) an amount up to about 20% by weight of a waxy material; and
e) from about 10 to about 95% by weight of a plasticizer.
The adhesive compositions of the present invention may also be useful as a waterproof coating which could be coated onto any fabric or nonwoven surface that is intended to be resistant to water penetration.
DETAILED DESCRIPTION OF THE INVENTION
The hot melt adhesive composition of the present invention comprises a substantially linear A-B-A block copolymer wherein A is polystyrene and B is a substantially saturated rubbery midblock comprising ethylene/propylene, ethylene/butylene and mixtures thereof. This copolymer can be present in an amount from about 5 to about 40% by weight, preferably in an amount from about 20 to about 30% by weight. Examples of such polymers include those commercially available under the Kraton G® tradename from Shell Chemical Company. Branched or grafted versions of the Kraton G® polymers such as TKG-101 and RP-6912 are also suitable for use, either alone or in combination with other ungrafted Kraton G® polymers. The high cohesive strength and high plasticizer loading capacity of this copolymer is critical to the success of the present invention. It enables the resulting adhesive composition to exhibit a sufficiently low viscosity and low surface tension in the molten state so that it readily flows along the stitch line and wicks into the seam and stitch holes when applied. Upon cooling, the adhesive also maintains its flexibility over a wide temperature range. This is especially important because the seam thus formed would be required to endure extensive flexing. The copolymer also exhibits oxidative stability and good UV resistance, thus insuring good durability and longevity of the resulting waterproof seam.
Preferably, the adhesive composition comprises a second polymer, present in an amount up to about 15% by weight, more preferably in an amount of about 5 to about 10% by weight of a substantially A-B diblock copolymer. This polymer can be a solid or liquid at ambient temperature. Representative examples include those that are available from Shell Chemical Company under the tradename Kraton® G-1726 or LVSI-101.
The adhesive composition of the present invention preferably comprises a tackifying resin. This can be present in amounts up to about 20% by weight. Ideally, the tackifier is aromatic in nature, so it will preferably associate with the polystyrene end blocks. Examples of such resins are available from Hercules Inc. under the tradename Kristalex® and typically have softening points between 70° C. and 160° C. Midblock tackifiers may also be useful in the adhesives of the present invention so long as the resulting adhesive is not sufficiently tacky upon cooling. Midblock tackifiers are known in the art, and representative examples include polyterpene resins, coumarone-indene resins, hydrogenated rosins and rosin ester, as well as aliphatic and aromatic petroleum hydrocarbon resins.
A waxy material can also be present in the adhesive composition of the present invention. Preferably, the waxy material is present in amounts up to about 20% by weight, more preferably, in amounts ranging from about 1 to about 10% by weight. The waxy material is added to modify the viscosity, reduce the tack, and enhance the water barrier properties. The preferred waxy material includes any petroleum derived paraffin wax. Other useful waxes include microcrystalline waxes, Fischer-Tropsch, polyethylene and by-products of polyethylene.
Plasticizing agents, especially oils are also useful in the adhesive compositions of the present invention. Preferably, the plasticizing agent is a liquid at ambient temperature, and these include naphthenic or paraffinic hydrocarbon oils. Other useful plasticizers include polybutene, liquid tackifying resins, and liquid elastomers so long as the resulting adhesive is sufficiently tack free upon cooling. Others plasticizers include olefinic oligomers, low molecular weight polymers, vegetable oils and their derivatives thereof.
Various other components can also be added to modify the tack, color, odor, etc., of the hot melt adhesive compositions of the instant invention. These can include antioxidants and other stabilizing ingredients which are added to protect the adhesives from various heat and light induced degradation.
EXAMPLES
Examples 1-3 were made in the following manner in accordance with known hot melt manufacturing methods. The A-B-A block copolymer, antioxidant, resin, and about one half the oil was added to a sigma blade mixer with a hot oil temperature of about 350° F. (˜ 177° C.). The ingredients are shown in Table 1. These were sheared for about 45 minutes until smooth. The diblock A-B block copolymer, wax and the remainder of the oil were then added sequentially.
APPLICATION METHODS
A bead of hot melt adhesive was applied by hand at a temperature of about 350° F. (˜ 177° C.) with Slautterback Mini Squirt II hot melt application equipment. An appropriate nozzle size and application rate was selected depending on the seam width, seam thickness, and thread size. Typically, 0.3" (˜ 7.6 mm) and 0.7" (˜ 18 mm) slot die spreader nozzles as well as the standard 0.7" diameter nozzle were used to produce an adhesive bead that could sufficiently cover the seam and wick into the thread and stitch holes. The mass of adhesive applied ranged from about 0.5 grams/linear inch to 3 grams/linear inch depending on the nozzle size and application rate. The sealed stitched seam was then conditioned for at least 24 hours at ambient temperature prior to flex testing.
TEST METHODS
A waterproof stitched seam was formed as described above and then tested using a Dynamic Water Penetration Tester available from Koehler Instrument Company, Inc. in accordance with ASTM D2099, Dynamic Water Resistance of Shoe Upper Leather by the Maeser Water Penetration Tester. During testing, the waterproofed stitched seam was mounted in a flex tester, immersed in a salt water bath, and mechanically flexed. Water leakage was detected by electrical conductance. The test results are also depicted in Table 1. All three samples exceeded the minimum requirement of 20,000 flexes.
TABLE 1______________________________________ Example Example ExampleIngredient Tradename 1 2 3______________________________________A-B-A Block Kraton G 26.0% 25.0% 28.0%Copolymer 1652A-B Block Kraton G -- 6.5 --Copolymer 1726A-B Block LSVI-101 7.0 -- --CopolymerTackifier Kristalex 8.0 -- -- 3100Tackifier Kristalex -- 7.0 -- 3085Wax Paraffin 4.0 3.0 5.0 155Plasticizer Kaydol Oil 54.8 -- 57.8Plasticizer 500 Oil -- 58.0 --Plasticizer Parapol -- -- 9.0 1300Antioxidant Irganox 0.1 0.3 0.1 1010Antioxidant Irganox 0.1 0.2 0.1 1076Viscosity @ not measured 18,650 cps 41,900 cps250° F.Viscosity @ 7,013 cps 7,288 cps 9,700275° F.Viscosity @ 3,130 cps 3,635 cps 3,300300° F.Viscosity @ 1,668 cps 2,085 cps not measured350° F.ASTM-D2099 Exceeded Exceeded Exceeded 40,000 22,000 20,000 flexes flexes______________________________________ | This invention relates to hot melt adhesive compositions useful for waterproofing stitched seams and a method of using the same. This invention particularly relates to certain hot melt adhesives which can be directly applied to a stitched seam such that the resulting seam is resistant to water penetration. | 2 |
RELATED APPLICATIONS
This application is related to the co-filed and co-assigned patent application entitled "Formation of Lightly Doped Regions Under a Gate," as U.S. Ser. No. 08/993,383 and issued as U.S. Pat. No. 5,990,532 on Nov. 23, 1999, which is hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates generally to integrated circuit manufacturing and more particularly to the formation of lightly doped regions under a gate of a transistor.
BACKGROUND OF THE INVENTION
An insulated-gated field-effect transistor (IGFET), such as a metal-oxide semiconductor field-effect transistor (MOSFET), uses a gate to control an underlying surface channel joining a source and a drain. The channel, source and drain are located within a semiconductor substrate, with the source and drain being doped oppositely to the substrate. The gate is separated from the semiconductor substrate by a thin insulating layer such as a gate oxide. The operation of the IGFET involves application of an input voltage to the gate, which sets up a transverse electric field in the channel in order to modulate the longitudinal conductance of the channel.
The buildup or depletion of charge resulting from the application of a voltage to the gate creates a channel under the gate connecting the source and the drain. The surface of the semiconductor is said to be inverted. The source is biased with a voltage and the drain is grounded relative to the source. In this condition, a current starts to flow as the inverted surface creates an electrically connecting channel. The source and drain are essentially shorted together. Applying more voltage to the gate increases the size of the channel (height-wise), allowing more current to flow through the transistor. By controlling the gate voltage, an IGFET transistor can be used as a switch (on/off) or an amplifier.
Typically, a lightly doped drain (LDD) extension is created within the substrate adjacent to each side of the gate. Such lightly doped regions are usually created by first applying an ion implantation to lightly dope the substrate, and then forming a spacer, such as a nitride spacer, to each side of the gate to act as a mask for a second ion implantation to create heavily doped regions (i.e., the source and drain regions). The channel length of such a transistor, therefore, is the width of the gate itself, since the area of substrate underneath the gate between the lightly doped regions is the same length as the gate width.
For high-performance IGFET applications, such as microprocessors, short channel length is desirable; the shorter the channel length, the less distance the carriers have to traverse in order to move from the source to the drain. LDD extensions are in fact used because in IGFETs having channel lengths less than two micron, the heavily doped regions of the source and the drain may otherwise bridge without the presence of the extensions. Furthermore, because of constraints in the minimum width to which a gate may be formed (as a result of either external requirements such as a certain length necessary for salicidation or metal contact connectability or processing limitations such as the minimum width that photoresist can be selectively sized to create the gate) the length of the channel is usually limited, too. Performance barriers are thus reached as minimum gate size is attained.
This is undesirable and becomes especially disadvantageous and problematic in applications where speed is of the utmost importance, such as in microprocessors. There is a need, therefore, to fabricate transistors having short channels than may otherwise be possible where channel length is equal to gate width.
SUMMARY OF THE INVENTION
The above-mentioned shortcomings, disadvantages and problems are addressed by the present invention, which will be understood by reading and studying the following specification. The invention relates to the formation of lightly doped regions under a gate of a transistor that has a reduced gate oxide. In one embodiment, a method includes four steps. In the first step, a gate is formed over a semiconductor substrate. In the second step, the gate oxide is etched to reduce the length of the gate oxide. In the third step, a first ion implantation is applied, at an angle other than perpendicular to the substrate, to desirably form lightly doped regions within the substrate underneath the gate. Finally, in the fourth step, a second ion implantation is applied, perpendicular to the substrate, to desirably form heavily doped regions within the substrate adjacent to the gate.
Thus, the channel length of a transistor formed pursuant to this embodiment of the invention is less than the width of the gate, because of the reduction of the gate oxide, and the angled ion implantation. The channel length is measured within the substrate between the lightly doped regions underneath the gate. The etching in the second step enables the first ion implantation to create these lightly doped regions underneath the gate. This means that for the same-sized gate as may be found in a prior art transistor, a transistor according to the invention will have a shorter channel, generally meaning that the inventive transistor will have better performance characteristics than those of the prior art transistor. This is an advantage of the invention.
The present invention describes methods, devices, and computerized systems of varying scope. In addition to the aspects and advantages of the present invention described here, further aspects and advantages of the invention will become apparent by reference to the drawings and by reading the detailed description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1F show cross-sectional views of successive process steps for making an IGFET in accordance with one embodiment of the invention; and,
FIG. 2 is a diagram of a computerized system, in accordance with which the invention may be implemented.
DETAILED DESCRIPTION OF THE INVENTION
In the following detailed description of exemplary embodiments of the invention, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific exemplary embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical, mechanical, electrical and other changes may be made without departing from the spirit or scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims.
Described first is an IGFET known as a MOS. In FIG. 1A, silicon substrate 102 suitable for integrated circuit manufacture includes P-type epitaxial layer with a boron background concentration on the order of 1×10 16 atoms/cm 3 , a <100>orientation and a resistivity of 12 ohm-cm. Desirably, the epitaxial surface layer is disposed on a P+ base layer, not shown, and includes a planar top surface. Gate oxide 104, comprise of silicon dioxide, is formed on the top surface of substrate 102 using oxide tube growth at a temperature of 700E to 1000E C, in an O 2 containing ambient. A typical oxidation tube contains several sets of electronically powered heating coils surrounding the tube, which is either quartz, silicon carbide, or silicon, desirably. In O 2 gas oxidation, the wafers are placed in the tube in a quartz "boat," and the gas flow is directed across the wafer surfaces to the opposite or exhaust end of the tub. Gate oxide 104 has a thickness of 30 angstroms, desirably.
Thereafter, a blanket layer of undoped polysilicon 106 is deposited by low pressure chemical vapor deposition (LPCVD) on the top surface of gate oxide 104. Polysilicon 106 has a thickness of 2000 angstroms, desirably. If also desired, polysilicon 106 can be doped in situ as deposition occurs, or doped before a subsequent etch step by implanting arsenic with a dosage in the range of 5×10 14 to 5×10 15 atoms/cm 2 , and an energy in the range of 2 to 80 keV. However, it is generally desired that polysilicon 106 be doped during an implantation step following a subsequent etch step.
In FIG. 1A, the polysilicon 106 deposited on the substrate 102 is implanted with arsenic ions and then with nitrogen ions, as depicted by arrows 160. The arsenic ions enhance the rate of silicon dioxide growth in subsequent oxidation processes used to add or grow an additional layer of silicon dioxide. The arsenic ion implant has a dosage in the range of 5×10 14 to 5×10 15 atoms/cm 2 , and an energy level ranging between about 2 to 80 keV. Doping with nitrogen is optional. The arrows 160 depict either the single step of doping with arsenic ions, or the two steps of doping with arsenic and then doping with nitrogen ions. The nitrogen ions may be added to retard the diffusion of the arsenic atoms. If the polysilicon is to be doped with nitrogen ions, the polysilicon may be implanted at this point in the process at a dosage of 5×10 14 to 5×10 15 atoms/cm 2 , and at an energy level of 20 to 200 keV. Nitrogen ions may be implanting after etching the polysilicon.
In FIG. 1B, photoresist 110 is deposited as a continuous layer on polysilicon 106 and selectively irradiated using a photolithographic system, such as a step and repeat optical projection system, in which I-line ultraviolet light from a mercury-vapor lamp is projected through a first reticle and a focusing lens to obtain a first image pattern. Thereafter, the photoresist 110 is developed and the irradiated portions of the photoresist are removed to provide openings in photoresist 110. The openings expose portions of polysilicon 106, thereby defining a gate.
In FIG. 1C, an anisotropic etch is applied that removes the exposed portions of polysilicon 106 and the underlying portions of gate oxide 104. Desirably, a first dry etch is applied that is highly selective of polysilicon, and a second dry etch is applied that is highly selective of silicon dioxide, using photoresist 110 as an etch mask. After etching occurs, the remaining portion of polysilicon 106 provides polysilicon gate 112 with opposing vertical sidewalls (or, edges) 114 and 116. Polysilicon gate 112 has a length (between sidewalls 114 and 116) of 500-2500 angstroms, desirably.
In FIG. 1D, photoresist 110 is stripped, and an etchant is applied that removes a portion of gate oxide 104. The result is that the L eff of gate 112 is ultimately reduced, as can be appreciated by those skilled in the art. The etching of FIG. 1D is desirably a wet or dry oxide etch.
In FIG. 1E, lightly doped regions 124 and 126 are formed by an ion implantation at an angle other than perpendicular to the substrate 102. The ion implantation may be arsenic, boron, or any other suitable dopant. The lightly doped region 124 is formed within substrate 102 adjacent to gate 112 as a result of this ion implantation. Because the ion implantation is performed at an angle other than perpendicular to the substrate 102, lightly doped regions 126 within substrate 102, underneath gate 112 and gate oxide 104, are also formed. The ion implantation is represented as arrows 122 in FIG. 1E. Desirably, the angle of the ion implantation is from thirty to forty-five degrees as measured from an axis perpendicular to the substrate.
Finally, in FIG. 1F, a second ion implantation is applied, at an angle perpendicular to the substrate. The ion implantation is generally the same dopant as that which was applied in the first ion implantation. The heavily doped drain regions 130 are formed within substrate 102 adjacent to gate 112 as a result of this second ion implantation. Because the second ion implantation is performed at an angle perpendicular to the substrate 102, the lightly doped regions 126 within substrate 102 are unaffected by the second ion implantation, such that they remain lightly doped. The second ion implantation is represented in FIG. 1F by arrows 128.
The channel length 132 of the transistor shown in FIG. 1F is measured as the distance within substrate 102 between the lightly doped regions 126. Because the lightly doped regions 126 are underneath the gate 112, and because oxide 104 has been etched away, the channel length 112 is less than the width of the gate 112. This is advantageous to prior art transistors in which the lightly doped regions are adjacent to (and not underneath) the gate, because it results in a transistor having the same gate size, but a shorter channel length, resulting in a faster-performance transistor. Desirably, the channel length 112 is between 0.04 micron and 0.15 micron.
Not shown in FIG. 1F are the conventional processing steps of metal salicidation, placing glass over the surface, and forming a contact opening for subsequently placed connectors. A passivation layer may also then be deposited as a top surface. Additionally, the principal processing steps disclosed herein may be combined with other steps apparent and known to those skilled in the art. The invention is not particularly limited in this regard.
Referring next to FIG. 2, advantageously the invention is well-suited for use in a device such as an integrated circuit chip, as well as an electronic system including a central processing unit, a memory and a system bus. The electronic system may be a computerized system 500 as shown in FIG. 3. The system 500 includes a central processing unit 500, a random access memory 532, and a system bus 530 for communicatively coupling the central processing unit 504 and the random access memory 532. The system 500 includes a device formed by the steps shown in and described in conjunction with FIGS. 1A-1G. The system 500 may also include an input/output bus 510 and several peripheral devices, such as devices 512, 514, 516, 518, 520 and 522, which may be attached to the input/output bus 510. Peripheral devices may include hard disk drives, floppy disk drives, monitors, keyboards, and other such peripherals.
Formation of lightly doped regions under a gate of a transistor having a reduced gate oxide has been described. Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that variations and adaptations may be substituted for the specific embodiments shown. Therefore, it is manifestly intended that this invention be limited only by the following claims and equivalents thereof. | The formation of lightly doped regions under a gate of a transistor that has a reduced gate oxide is disclosed. In one embodiment, a method includes four steps. In the first step, a gate is formed over a semiconductor substrate. In the second step, the gate oxide is etched to reduce the length of the gate oxide. In the third step, a first ion implantation is applied, at an angle other than perpendicular to the substrate. Finally, in the fourth step, a second ion implantation is applied, perpendicular to the substrate. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a method for the controlling of a fabric through a rotary screen printing installation, whereby the substrate, the fabric to be printed upon, is wound from a stock roll via a wind-off roller and fed to the printing machine of the installation, and the substrate is then fed through a drying installation and wound up.
A rotary screen printing installation of this type is generally known.
SUMMARY OF THE INVENTION
The object of the present invention is to improve the control of the input such that the down times and/or lower production speeds are reduced.
A further object of the present invention is the automatic registration of the total number of meters of fabric used and the automatic registration of the number of meters of fabric that is printed with first-choice quality.
Finally, it is an object of the invention to carry out a number of checks automatically during printing and to increase the total production speed and to reduce the amount of waste in the form of fabric not printed with first-choice quality.
The above objects of the present invention and others are achieved according to the invention in the following manner:
A predetermined length of a fabric of low quality, the so-called leader, is fed into the installation for setting a printing machine, a portion being stored in a buffer.
A substrate to be printed is sewn to the leader and the length of the print order is stored in the memory of an electronic processing unit.
The printing machine is set whilst emptying the buffer.
The intake of the substrate is started at low speed, a signal for measuring the length of the substrate fed in being given to the processing unit when the seam between the leader and the substrate passes the windoff roller.
a signal for measuring the length of the printed substrate of first quality is given to the processing unit when the seam has passed through the printing machine and the printing machine is set to first quality.
The measured length of substrate of first quality is compared with the length of the print order stored in the memory.
The use of a leader, being fabric of low quality, has the advantage that the printing machine can be set (brought into register) on inexpensive fabric, so that the amount of waste of the substrate to be printed, which is mostly expensive, can be kept to a minimum. The quantity of leader required, which is necessary for bringing the printing machine into register, is known from experience and dependent on the number of printing positions in operation or of colors required. The substrate to be printed is measured from the point when the seam between the leader and the substrate passes the wind-off roller, so that the total quantity of substrate fed in is measured. A further signal is given to the processing unit from the point when the printing machine is set to print with first quality, so that the length of substrate printed with first quality is also measured. Thus, the total quantity of substrate and the quantity of substrate of first quality are measured in the processing unit, the latter quantity being compared with the length of the print order previously entered in the processing unit. In this way not only is the quantity of fabric used automatically recorded, but the machine can also be set for a minimum percentage of waste of the substrate to be printed, while, as a result of the presence of the buffer, the down times can be reduced or can be avoided.
Preferably, the method according to the invention can be further extended in the following manner.
A signal is given by the electronic processing unit if the difference between the measured length of first quality and the length of the print order is less than a pre-determined value (a).
The speed of the printing machine is brought back to, or kept constant at, a pre-determined value and the speed of the intake is increased to a speed which is much higher than that of the printing machine, so that the buffer is filled.
The feed stops when the length of the substrate required for carrying out the print order has been fed into the intake.
The substrate is cut off and leader sewn firmly onto the trailing end of the substrate and,
a signal is given to the processing unit when the seam between the substrate and the leader passes the wind-off roller, by which means the exact quantity of substrate used is known.
The buffer is filled with as much leader as is needed for setting the printing machine for carrying out the subsequent print order; and
the printing machine is stopped when the seam between the substrate and the leader has exited from the drying installation.
After completion of the print order, the entire installation is thus filled with sufficient leader to set the printing machine for the following print phase. Since the trailing end of the substrate is again connected to leader, there are, moreover, no changed conditions in the printing installation, so that the final end of the substrate passing through the drying installation shows no deviations with respect to the preceding portion of the substrate.
According to the invention there is also provision that the quantity of substrate on the stock roll is measured during printing and, if the measured length is less than the value (a), the intake is accelerated for filling the buffer until the entire roll has been fed in, a new stock roll is placed in position and the new web is firmly sewn to the trailing end of the preceding web.
If the quantity of substrate on the stock roll at the end of the print order is less than a pre-determined value (b), it is also possible, according to the invention, to feed in the residual portion of the substrate. In this way, the number of stock rolls (docks) with a minimum quantity of residual substrate in the warehouse is reduced.
Thus, with the aid of the method according to the invention, the number of meters of fabric used is recorded automatically, it also being possible to enter in the electronic processing unit from which docks the fabric was taken, so that stock control can also be automated.
Preferably, according to the invention, during actual printing of the substrate the substrate web runs taut through the buffer, and the buffer is then empty.
The invention is illustrated in more detail with the aid of the drawing, wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 gives a schematic side view of the rotary screen printing installation, and
FIG. 2 is an enlarged representation of the intake section of the installation from FIG. 1.
DETAILED DESCRIPTION
As can clearly be seen from FIG. 1, the rotary screen printing installation consists of an intake section 1, a printing machine 2 and a take-off section 3. The intake section comprises a stock roll 4 of a substrate to be printed, which runs through the installation according to the web 5 in the direction of the arrow P. In the representation shown schemtically in FIG. 1, the web 5 runs from the stock roll 4 essentially via a wind-off roller 6 through a buffer 7, a pre-treatment installation 8 and a roller 9 via a curved surface 10 to the screen printing machine 2.
The printing machine is provided with a number of parallel cylindrical stencils 12 rotatably bearing-mounted herein. In the embodiment shown, there are eight stencils, which each represent one print position. From the printing machine the web 5 then passes into the take-off section 3. This take-off section essentially comprises a drying installation 13, via which installation the web is wound, via tension adjusting devices and guide rollers, which are not described in more detail, on a stock roll 14.
The screen printing installation shown in FIG. 1 and described briefly here is described in more detail in the related published Netherlands patent application 8702408 of Applicant, to which reference is made here.
In FIG. 2 the intake section 1 of the installation is shown on an enlarged scale and in more detail. In this figure the same parts are shown as far as possible with the same reference numbers as in FIG. 1. FIG. 2 again shows the stock roll 4 of the substrate to be printed, the substrate being wound off via the wind-off roller 6 located at the outer end of a swivelling lifting arm 15, which lifting arm is operated by a piston-cylinder assembly 16. During the printing process, the lifting arm 15, with the wind-off roller 6, rests against the stock roll 4. The wind-off roller 6, which is provided with a measuring device for the continuous measurement of the length of fabric passing over it, is driven by slip-free chain transmissions with the aid of a motor 17 and a reduction gear unit 18. The web 5 of the substrate to be printed then runs via a drive roller 19 into the buffer 7, which roller 19 is likewise driven by the motor 17 with a circumferential speed which is slightly greater that that of the wind-off roller 6. In contrast to FIG. 1, in FIG. 2 the web 5 runs taut through the buffer 7. As will be described in more detail below, this situation arises during the phrase of actual printing of the substrate. Via the buffer 7, the web then runs through a leveller 20 and a compensator or tension adjuster 21, which regulates the speed of the motor 17 depending on the tension of the fabric. From the compensator, the web 5 then runs to a fabric control device or stretcher 22.
Via this control device, the web runs via the pre-treatment installation 8 (for example for removing dust) to a drive roller 25, which is driven by a motor 23 and a reduction gear unit 24. From this device roller 25, the web runs through a second compensator 26, which regulates the speed of the motor 23 depending on the tension of the fabric. Via this latter compensator, the web 5 is fed via the roller 9 over the curved surface 10, after which the web is fed into the printing machine 2.
The intake section 1 of the rotary screen printing installation also contains a holder 27 for a roll 28 of a fabric of low quality, the so-called leader. As will be described in more detail below, this relatively inexpensive leader serves for setting the printing machine 2 so that, in this way, the loss of relatively expensive substrate as waste can be kept as small as possible. A sewing machine 29 is also provided for sewing the webs to one another when the stock roll is changed.
Before the start of a new print order the entire installation is filled with leader which extends from the roll 28 via guide rollers and the wind-off rollers 6 through the machine in accordance with the web 5 shown. If leader is fed into the installation from the roll 28, the lifting arm 15 is in the raised position shown in FIG. 2. In this starting stage, the buffer 7 is filled with leader so that the web 5 is in loops in the buffer, as shown schematically in FIG. 1. The length of the leader fed in depends on the number of print positions which are needed for carrying out the particular print order and is known from experience.
The data for the print order now to be carried out, i.e. the length of first quality, are entered into an electronic processing unit. The leader is then cut from the roll 28 and, with the aid of the sweing machine 29, the substrate from the stock roll 4 is firmly sewn to the trailing end of the leader fed into the installation. The printing machine 2 is now started at low speed, the operator setting the machine (bringing it into register) while this machin is using the low quality fabric stored in the buffer 7. In the situation that fabric from the buffer is used, the leveller 20 is reversed so that the fabric in front of the leveller, seen in the direction P of movement of the fabric, hangs slack, while beyond the leveller 20 the fabric is kept at tension as a consequence of the friction exerted on the fabric by the leveller.
The leveller 20 can, for example, be controlled by a photo-electric cell which is fitted in the buffer and which recoreds whether or not the buffer is filled. If the buffer is empty, the fabric runs taut through the buffer 7 and the leveller is set such that there is no difference in tension in the web over the leveller 20. In this situation the fabric is kept at tension by the compensator 26, which controls the drive motor 23.
Towards the time that the buffer starts to run empty, the intake of substrate is started via the wind-off roller 6, which rests against the roll 4 and is driven by the motor 17. The fabric now runs taut through the buffer 7 as shown in FIG. 2. If the seam between the leader and the substrate passes the wind-off roller 6, a signal is given to the electronic processing unit, so that from this point the quantity of substrate supplied is automatically measured. When the seam has passed through the printing machine and the operator, in the meantime, has brought the machine into register such that a print of first quality is obtained, a further signal is given to the processing unit, which from this point records the quantity of substrate printed in first quality. In this way, thus, both the total quantity of substrate and the quantity of substrate printed in first quality are measured, the difference between these two amounts being noted as waste.
When the measured length of printed substrate of first quality approaches the total length of the print order previously entered in the processing unit to within, for example, about 300 meters, an acoustic signal is given by the processing unit. The printing speed is automatically brought back to a maximum of 40 m/min., or is kept constant if the printing speed is lower. The intake is now accelerated to a speed of about 100 m/min., so that the buffer is filled until the total number of meters of substrate to be printed for the particular order had been fed in. It will be clear that during this operation the leveller 20 is again reversed so that the fabric can be kept at tension beyond this leveller. The substrate is now cut at the intake and leader is sewn firmly to the trailing end of the substrate fed into the installation, this thus being carried out while the printing machine continues to run and uses substrate from the buffer. The leader is now fed in in synchronization with the speed of the printing machine. When the seam between the substrate and the leader has passed the wind-off roller, a signal is given to the processing unit, the precise number of meters of substrate fed in then being known. As much leader is fed into the buffer as is necessary to set the printing machine for carrying out the subsequent print order, which quantity is known from the experience and is dependent on the number of print positions of the printing machine 2 which are to be used.
When the buffer is filled with sufficient leader, the intake stops, while the printing machine continues to print normally and stops automatically as soon as the final meter of the substrate to be printed has exited from the dryer. The stockroll 4 with residual substrate can be removed and brought back to the stores, after which the installation is ready for carrying out the next print order.
During printing, the quantity of substrate present on the stock roll is also measured, which can be effected, for example, via the angular position of the lifting arm 15 or by measuring the distance between the outer edge of the stock roll and the core of the roll. This value is also entered into the processing unit. If the quantity of substrate remaining on the roll after the print order is complete is less than a pre-determined minimum length, the residual portion of the substrate is automatically also printed until the entire roll has been used. The minumum residual stock which is still acceptable can be changed per print order and/or per roll. In this way it is avoided that a large number of rolls with too small a stock are left over.
In the case of large print orders it can be possible that several stock rolls are needed. If the processing unit establishes, via the measurement of the substrate stock, that this stock is less than 300 meters and the total print order is not yet complete with this, the intake is automatically accelerated to fill the buffer. The entire stock roll is rapidly fed in and the empty roll is then changed for the following roll and the new web is firmly sewn onto the trailing end of the substrate fed into the installation. After the substrate from the new roll has been firmly sewn anys substrate still present in the buffer is pulled through and the intake starts from the new stock roll, the substrate then again running taut through the buffer. In this way the stock roll can be changed without the printing machine having to be stopped. By also entering the numbers of the stock rolls into the processing unit, the warehouse stock control can also be automated. | Method for controlling the passage of the fabric through a rotary screen printing installation, whereby a substrate or fabric to be printed is wound from a stock roll and fed into the printing machine of the installation. In order to reduce down times and the waste of mostly expensive substrate the printing machine is set using a fabric of low quality, the so-called leader. The substrate to be printed is sewn to the trailing end of the leader so as to print the substrate after the printing machine is set for first quality printing. The length of substrate is measured and compared with the total length of the print order by means of an electronical processing unit. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to a coating composition of positive photosensitive polyimide, which is applicable as an insulating layer in displays.
BACKGROUND OF THE INVENTION
[0002] Due to its excellent thermal stability and good mechanical, electrical and chemical properties, polyimide (PI) is widely used in semiconductor and display industries, e.g. encapsulation film of IC chip, and insulator in chip scale package (CSP) and display, etc. Since the use of photosensitive polyimide (PSPI) can provide simplification of fabrication processes, reduction of cost and a higher yield, the use of PSPI has become a trend.
[0003] There are numerous publications related to PSPI. However, most of them are related to precursors of polyimide, e.g. poly(amic ester), such as those disclosed in U.S. Pat. No. 6,329,110, U.S. Pat. No. 6,291,619, U.S. Pat. No. 6,232,032 and U.S. Pat. No. 5,858,584, etc. The pattern developed by poly(amic ester) is a standard rectangle. However, the insulating layer in a display needs to have a pattern with tapered-angle at the cross section disclosed in U.S. Pat. No. 6,222,315. Furthermore, the poly(amic ester) needs to be imidized at 350° C. which is in conflict with the requirement of process temperature of lower than 250° C. Thus, PSPI made from poly(amic ester) is not feasible. Imidized PSPI has been disclosed, e.g. U.S. Pat. No. 6,627,377, U.S. Pat. No. 5,441,845, U.S. Pat. No. 5,5738,86, etc. Although, such imidized PSPI has a lower post-cure temperature, usually it is a soluble PI with a generally poor solvent resistance. Furthermore, such imidized PSPI needs to be developed with an alkaline solution having a high concentration, and thus is not suitable.
[0004] Masao Tomikawa et al. in Journal of Photopolymer Science and Technology, 2002, 15, 205˜208, U.S. Pat. No. 6593043 and U.S. Pat. No. 6,524,764 have disclosed a positive-type photosensitive polyimide presursor composition comprising a poly(amic ester) having phenolic hydroxyl group at the ends of the main chain thereof and a compound having phenolic hydroxyl group as the crosslinking agent, such that the pattern formed has a tapered-angle at the cross section. However, the main structure of the polyamic acid ester still needs to be imidized at a high temperature in order to ensure a complete imidization. Examples 6-13 of U.S. Pat. No. 6,524,764 show that shrinkage takes place when the polyamic acid ester is converted to polyimide. As a result, the film thickness retention rate of the PSPI formed from polyamic acid ester is low (66%). Further, the synthesis of the poly(amic ester) having phenolic hydroxyl group at the ends of the main chain thereof is complicated.
SUMMARY OF THE INVENTION
[0005] One objective of the present invention is to provide a novel coating composition of positive photosensitive polyimide, which can be synthesized easily, developed by an alkaline aqueous solution in a short time, and has a high sensitivity, good resolution, low post-cure temperature, high film thickness retention rate, and a tapered-angle at the cross section after post-cure. The invented coating composition can be stored stably at room temperature.
[0006] A positive photosensitive polyimide coating composition prepared according to the present invention comprises an organic solvent and, dissolved in said organic solvent, (a) a polyimide having a phenolic hydroxyl group or carboxyl group at an end of a principal chain of the polymer, (b) a compound having a phenolic hydroxyl group, and (c) a quinonediazide sulfonate as a photosensitive agent, wherein the amount of the component (b) is 1-50 parts by weight per 100 parts by weight of the component (a) in the coating composition, and the amount of the component (c) is 1-50 parts by weight per 100 parts by weight of the component (a) in the coating composition.
[0007] Preferably, said polyimide (a) has the following structure (1) or (2):
wherein n is an integer of 10-600, Ar 1 is a tetra-valent organic group, Ar 2 is a bi- to tetra-valent organic group, Ar3 is a bi-valent aryl, R1 is OH group or COOH group.
[0008] More preferably, Ar 3 in the structures (1) and (2) is
[0009] Ppreferably, Ar 1 in the structures (1) and (2) is
[0010] Preferably, Ar 2 in the structures (1) and (2) is
wherein m is an integer of 1-20, and X 1 is
wherein m is an integer of 1-20, and Z is H or methyl.
[0011] Preferably, the amount of the component (b) is 5-25 parts by weight per 100 parts by weight of the component (a) in the composition.
[0012] Preferalby, wherein said compound having a phenolic hydroxyl group (b) has the following structure:
wherein R 3 to R 9 independently are H, —OH group, C 1 -C 20 alkyl or C 4 -C 20 cycloaliphatic group, and z is an integer of 0-5. More preferably, said compound having a phenolic hydroxyl group (b) is:
[0013] Preferably, the component (c) as a photosensitive agent has the following structure:
wherein D of each occurrence is hydrogen,
provided that not all occurrences of D are hydrogen.
[0014] Preferably, the total weight of components (a), (b) and (c) is 5-50% of the total weight of said composition.
[0015] Preferalby, said organic solvent is N-methyl-2-pyrrolidone, γ-butyrolactone, or ethyl lactate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIGS. 1 a and 1 b separately show the scanning electron microscope (SEM) photos of top view and cross-sectional view of the pattern by using the positive photosensitive polyimide coating composition prepared in Example 1 of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] A polyimide suitable for use in the present invention may be synthesized by the following steps: dissolving a suitable amount of a diamine monomer and a dianhydride monomer in a suitable organic solvent, e.g. N-methyl-2-pyrrolidone (NMP); vigorously mixing the resulting mixture at 0˜4° C. for 4 hours; adding an endcapped agent (e.g. a primary amine with a phenoxyl or carboxyl group) into the mixture and stirring the mixture for 4 hours; adding xylene into the mixture and heating the mixture at 180° C. under refluxing for about 3 hours; and cooling the mixture to obtain a polyimide (PI) solution having a phenoxyl or carboxyl group at the end of the main chain thereof. A solution of photosensitive polyimide (PSPI) according to the present invention may be prepared by preparing a suitable amount of a PI solution, adding a crosslinking agent having phenolic hydroxyl group and a photosensitive agent, and optionally adding a solvent, such as NMP, γ-butyrolactone (GBL), or ethyl lactate, etc., into the solution in order to dilute the PSPI solution to a desired concentration for use.
[0018] A photolithographic process by using the PSPI solution of the present invention includes: (i) coating a PSPI solution on a suitable substrate by using a spin coating or other coating process; (ii) prebaking the coating; (iii) imagewise exposing the prebaked coating; (iv) developing the exposed coating; and (v) post-curing the developed coating, thereby obtaining a polyimide (PI) pattern. In step (i), a positive PSPI solution is coated on a suitable substrate, e.g. silicon substrate, glass, or ITO glass. A suitable coating technique includes, but not limited to, spin coating, roller coating, screen coating, curtain coating, dip coating, and spray coating. In a preferred embodiment according to the present invention, a layer resulting from the coating is prebaked at 70˜120° C. for a few minutes to evaporate the solvent contained therein. Next, the coated substrate is imagewise exposed to a photo irradiation under a photomask. The abovementioned photo irradiation includes, for example, X-ray, electron beam, UV ray, visible ray, or any photo source suitable for being used as a photo irradiation source.
[0019] After exposure, said coated substrate is subsequently developed with an alkaline aqueous developer solution to remove the exposed portion of said coating layer, so that the pattern of the photomask is transferred. Said alkaline aqueous developer solution may be an alkaline aqueous solution, e.g. an aqueous solution of an inorganic alkaline (potassium hydroxide, or sodium hydroxide), a primary amine (ethylamine), a secondary amine (diethylamine), a tertiary amine (triethylamine), or a quaternary ammonium salt (tetramethylammonium hydroxide), and preferably an aqueous solution of tetramethylammonium hydroxide (TMAH). Developing can be accomplished by immersion, spraying, or other known developing methods. The resulting patterned layer is subsequently washed with deionized water and post-cured at 180˜400° C. to remove residual solvent, thereby obtaining a polyimide pattern with a tapered-angle at the cross section.
[0020] The film residual rate is calculated according to the following formula:
film residual rate (%)=[(film thickness after post-cure)/(film thickness after prebake)]
[0021] The present invention can be better understood by the following examples, which are for illustrative only and not for limiting the scope of the present invention.
Chemical Agents:
ethylene glycol bis(anhydro-trimellitate) (TMEG)
bis(3,4-dicarboxyphenyl)ether dianhydride (ODPA)
3,3-dihydroxybenzidine (HAB)
Hexofluoro-2,2-bis(3-amino-4-hydroxyphenyl) (BisAPAF)
3,5-diaminobenzoic acid (3,5-DABA)
4,4′-Oxydianiline (ODA)
2,2-bis(4-(4-aminophenoxyl)phenyl)propane (BAPP)
2,2-bis(4-(3-aminophenoxyl)phenyl)sulfone (m-BAPS)
wherein D is
2,3,4-trihydroxy-benzophenone-1,2-diazonaphthoquinone-5-sulfonate (PIC-3, purchased from KOYO chemicals Inc.)
Crosslinking Agent:
EXAMPLE 1
[0022] To a 1000-ml three-necked round bottom flask equipped with a mechanical stirrer 18.3 g (50 mmole) of Bis-APAF, 12.3 g (30 mmole) of BAPP, 2.02 g (10 mmole) of ODA, 20.5 g (50 mmole) of TMEG, 15.5 g (50 mmole) of ODPA, and 400 g of NMP as solvent were added. The resulting solution was stirred at 0° C. for 4 hours, and 2.18 g (20 mmole) of 3-aminophenol as an endcapped agent was then added, followed by 4-hour stirring at room temperature. To the stirred solution 80 g of xylene was added, and was heated to 180° C. for 3 hours while stirring. After cooling, a viscous PI solution PI-1 was obtained. An IR spectral analysis shows that the PI synthesized in this example has C═O and C—N characteristic absorptions at 1781 cm −1 and 1377 cm −1 of an imide group, respectively. To 50 g of PI-1 solution 1.875 g of PIC-3, and 1.875 g of DML-PC (crosslinking agent) were added. The resulting solution was mixed uniformly to obtain a photosensitive polyimide coating composition PSPI-1. A spin coating process was used to coat the PSPI-1 coating composition on for 2 minutes, thereby obtaining a film having a thickness of about 1.1 μm (measured by Talystep). The coated ITO glass was exposed by receiving a photo energy of about 100 mJ/cm 2 from an un-filtered mercury arc lamp (with measured wavelengths of 250˜400 nm), and then developed by 2.38 wt % tetramethylammonium hydroxide (TMAH) aqueous solution for 35 seconds. Next, the developed film received a post-cure process in an oven at 230° C. under circulation for 30 minutes in order to obtain a heat resistant PI pattern. As shown in FIG. 1 a and FIG. 1 b , the resulting pattern has a line width and pitch of about 20 μm and the taper angle is 19.2°. The film thickness after post-cure is 1.0 μm. Comparing the film thickness after post-cure with the film thickness after prebake, the film has 91% of film residual rate.
EXAMPLE 2
[0023] To a 1000-ml three-necked round bottom flask equipped with a mechanical stirrer 7.6 g (50 mmole) of 3,5-DABA, 12.975 g (30 mmole) of m-BAPS, 1.54 g (7.5 mmole) of ODA, 32.8 g (80 mmole) of TMEG, 6.2 g (20 mmole) of ODPA, and 400 g of NMP as solvent were added. The resulting solution was stirred at 0° C. for 4 hours, and 2.73 g (25 mmole) of 3-aminophenol as an endcapped agent was then added, followed by 4-hour stirring at room temperature. To the stirred solution 80 g of xylene was added, and was heated to 180° C. for 3 hours while stirring. After cooling, a viscous PI solution PI-2 was obtained. To 50 g of PI-2 solution 1.875 g of PIC-3, and 1.0 g of MTPC (crosslinking agent) were added. The resulting solution was mixed uniformly to obtain a photosensitive polyimide coating composition PSPI-2. A spin coating process was used to coat the PSPI-2 coating composition on an ITO glass, followed by a prebake process by using a hot-plate at 110° C. for 2 minutes, thereby obtaining a film having a thickness of about 1.1 μm. The coated ITO glass was exposed by receiving a photo energy of about 120 mJ/cm 2 from an un-filtered mercury arc lamp (with measured wavelengths of 250˜400 nm), and then developed by 2.38 wt % TMAH aqueous solution for 35 seconds. Next, the developed film received a post-cure process in an oven at 230° C. under circulation for 30 minutes in order to obtain a heat resistant PI pattern. The resulting pattern has a line width and pitch of about 15 μm. The film thickness after post-cure is 0.95 μm. Comparing the film thickness after post-cure with the film thickness after prebake, the film has 86% of film residual rate. The resulting PI pattern has a tapered-angle at the cross section as shown in the SEM photo.
EXAMPLE 3
[0024] To a 1000-ml three-necked round bottom flask equipped with a mechanical stirrer 10.8 g (50 mmole) of HAB, 12.975 g (30 mmole) of m-BAPS, 2.02 g (10 mmole) of ODA, 41.0 g (100 mmole) of TMEG, and 400 g of NMP as solvent were added. The resulting solution was stirred at 0° C. for 4 hours, and 2.18 g (20 mmole) of 3-aminophenol as an endcapped agent was then added, followed by 4-hour stirring at room temperature. To the stirred solution 80 g of xylene was added, and was heated to 180° C. for 3 hours while stirring. After cooling, a viscous PI solution PI-3 was obtained. To 50 g of PI-3 solution 1.875 g of PIC-3, and 2.25 g of BIPC-PC (crosslinking agent) were added. The resulting solution was mixed uniformly to obtain a photosensitive polyimide coating composition PSPI-3. A spin coating process was used to coat the PSPI-3 coating composition on an ITO glass, followed by a prebake process by using a hot-plate at 110° C. for 2 minutes, thereby obtaining a film having a thickness of about 1.2 μm. The coated ITO glass was exposed by receiving a photo energy of about 120 mJ/cm 2 from an un-filtered mercury arc lamp (with measured wavelengths of 250˜400 nm), and then developed by 2.38 wt % TMAH aqueous solution for 40 seconds. Next, the developed film received a post-cure process in an oven at 230° C. under circulation for 30 minutes in order to obtain a heat resistant PI pattern. The resulting pattern has a line width and pitch of about 15 μm and a film thickness of about 1.05 μm. Comparing the film thickness after post-cure with the film thickness after prebake, the film has 87.5% of film residual rate. The resulting PI pattern has a tapered-angle at the cross section as shown in the SEM photo.
COMPARATIVE EXAMPLE 1
[0025] To a 1000-ml three-necked round bottom flask equipped with a mechanical stirrer 36.6 g (100 mmole) of Bis-APAF, 31.0 g (100 mmole) of ODPA, and 400g of NMP as solvent were added. The resulting solution was stirred at 0° C. for 4 hours, and 80 g of xylene was then added, and was heated to 180° C. for 3 hours while stirring. After cooling, a viscous PI solution PI-C1 was obtained. To 50 g of PI-C1 solution 1.8 g of PIC-3 was added. The resulting solution was mixed uniformly to obtain a photosensitive polyimide coating composition PSPI-C1. A spin coating process was used to coat the PSPI-C1 coating composition on an ITO glass, followed by a prebake process by using a hot-plate at 110° C. for 2 minutes, thereby obtaining a film having a thickness of about 1.1 μm. The coated ITO glass was exposed by receiving a photo energy of about 120 mJ/cm 2 from an un-filtered mercury arc lamp (with measured wavelengths of 250˜400 nm), and then developed by 2.38 wt % TMAH aqueous solution. After being developed for more than 3 minutes, a pattern still could not be obtained. An endcapped agent was not used for the synthesis of PI-C1 in comparative example 1.
COMPARATIVE EXAMPLE 2
[0026] To 50 g of PI-1 solution prepared in Example 1 1.875 g of PIC-3 was added. The resulting solution was mixed uniformly to obtain a photosensitive polyimide coating composition PSPI-C2. The photophotolithographic procedures in Example 1 were repeated, except that the developing time was 60 seconds. The film thickness after prebake is about 1.0 μm, and the post-baked pattern has a line width and pitch of about 20 μm and a film thickness of 0.8 μm (with a film residual rate of 80%). A SEM photo indicates that the cross-section of the PI pattern is rectangular without tapered-angle at the cross section. A crosslinking agent, a compound having a phenolic hydroxyl group, was not used in the preparation of the photosensitive polyimide coating composition PSPI-C2 in Comparative example 2.
COMPARATIVE EXAMPLE 3
[0000] Synthesis of HAB-ODPA-butanol-polyamic acid ester
[0027] To a 250-ml three-necked round bottom flask equipped with a mechanical stirrer and a nitrogen inlet 15.50 g (50 mmole) of ODPA, 7.40 g (100 mmole) of n-butanol, and 115 g of NMP as solvent were added. The resulting solution was heated to 80° C. and stirred for 4 hours for carrying out an esterification reaction. After the solution was cooled to 4° C., 16.63 g (200 mmole) of pyridine and 19.50 g (100 mmole) of phenylphosphonic dichloride were added, and the resulting solution was stirred at room temperature for 2 hours for carrying out an activation reaction of COOH group. The resulting solution was cooled to 0˜4° C., and 10.8 g (50 mmole) of HAB was added, which was then stirred at 0˜4° C. for 1 hour, and at room temperature for 8 hours for carrying out a polymerization reaction of polyamic acid ester. 1000 ml of methanol was added to form a precipitate in the reaction solution, the resulting precipitate was filtered out to obtain the polyamic acid ester. The collected polymer was washed with deionized water three times. Finally, the polyamic acid ester collected was dried in vacuo at 80° C. for 24 hours. 5 g of the resulting polyamic acid ester, 1.25 g of PIC-3, and 18.75 g of NMP as solvent were used to prepare a photosensitive polyimide precursor coating composition PSPI-C3. The photolithographic procedures in Example 1 were repeated, except that the developing time was 60 seconds. The film thickness after prebake is 1.0 μm, and the post-baked pattern has a line width and pitch of about 20 μm and a film thickness of 0.7 μm. Comparing the film thickness after post-cure with the film thickness after prebake, the film has 70% of film residual rate. Said film has a rectangular cross-section.
[0028] Said composition prepared in Comparative example 3 is an ordinary photosensitive polyimide precursor coating composition. Comparative example 3 is to emphasize that the conventional photosensitive polyimide precursor coating composition requires a post-cure treatment at 350° C. and has a lower film residual rate. | A coating composition of positive photosensitive polyimide is disclosed, which includes an organic solvent and the following components dissolved in the organic solvent: (a) a polyimide having a phenolic hydroxyl group or carboxyl group at the end of a principal chain of the polymer; (b) a compound having a phenolic hydroxyl group; and (c) a quinonediazide sulfonate as a photosensitive agent. The amount of the components (b) and (c) are 1-50 parts by weight per 100 parts by weight the component (a) in the coating composition. A film of the coating composition can be developed with an alkaline aqueous solution, which has a high photosensitivity, excellent resolution, low post-cure temperature, high film residual rate in thickness, and a pattern having a tapered-angle at the cross section. The coating solution can be used for forming an insulating layer in displays or in other suitable applications. | 2 |
FIELD OF THE INVENTION
The present invention relates in general to the removal of organic impurities from aqueous media such as potable water supplies using organophilic molecular sieve adsorbents. The organic contaminants are selectively adsorbed on the molecular sieve and effectively destroyed during regeneration of the adsorbent by conversion to innocuous materials such as CO 2 and H 2 O by reaction with a strong oxidant such as hydrogen peroxide. The efficiency of this regeneration reaction is found to be significantly enhanced by lowering the pH of the regeneration medium and/or increasing the number of Bronsted acid sites in the molecular sieve adsorbent.
DISCUSSION OF THE PRIOR ART
The contamination of supplies of potable water is a major public health concern throughout the world. Sources of ground water contamination are many and varied and include land fills, agricultural pesticides, leakage from stored gasoline, septic tanks, mining operations, petroleum and natural gas production and improperly constructed and maintained industrial toxic waste dumps. The discharge of chlorinated organics into the environment, is a cause of particular concern because of the known or suspected carcinogenic or mutagenic properties of some of these materials and the difficulty with which they are biologically degraded. In many instances chlorinated and other halogenated organic compounds pass through conventional industrial or municipal wastewater treatment plants essentially unaltered.
Several techniques have heretofore been proposed to detoxify or treat contaminated water, principal among which are the so-called air stripping procedure and the method involving the adsorption of the organic substrates on granulated activated carbon (GAC adsorption). The air stripping process involves stripping the volatile organics from water by contacting the contaminated water with air, most commonly in a countercurrent manner in a packed tower. Contaminated water is introduced at the top of the tower and as it flows down the tower, the volatile organics are stripped off by air that is flowing upwards following introduction at the bottom of the tower. The treated "clean" water is withdrawn at the bottom. A serious disadvantage with this technique is that the air, that is now contaminated with stripped off organics, is discharged into the atmosphere from the top of the tower. The organic pollutants are thus merely transferred from water to air. The technique, therefore, does not get rid of the undesirable pollutants. Other disadvantages to the method are the inability to deal with non volatile contaminants such as certain pesticides, and the tendency for the stripping tower to be affected by biological growth.
GAC adsorption processes are capable of removing both volatile and non volatile contaminants from aqueous media, but require expensive high carbon usage to obtain a purified water having non detectable levels of impurity. Also, the adsorption system is cumbersome to regenerate and, in any event, causes a secondary pollution problem in the disposal of the adsorbed impurities. A combination of both types, i.e. the air stripping and the GAC adsorption process is disclosed in U.S. Pat. No. 4,544,488 issued Oct. 1, 1985 to R. P. O'Brien. Other processes are disclosed in U.S. Pat. No. 4,526,692 issued July 2, 1985 to T. L. Yohe and U.S. Pat. No. 4,517,094 issued May 14, 1985 to G. W. Beall. It is also well known to disinfect or sanitize aqueous media such as recirculating water systems, effluents from food processing industries, paper mills, sewage stations and the like by the introduction of very strong oxidizing agents such as ozone. In this regard, see U.S. Pat No. 4,541,944 issued Sept. 17, 1985 to Sanderson.
A more recent development in the field is the adsorption-oxidation process disclosed in U.S. Pat. No. 4,648,977 issued to D. R. Garg et al Mar. 10, 1987. In accordance with this process, which is an entirely new approach to the problem, high silica molecular sieves which preferentially adsorb relatively non-polar organic molecules over highly polar compounds such as water, are utilized to adsorb organic contaminants from aqueous streams. For cyclic operation the adsorbate-loaded molecular sieves are treated with strong oxidizing compounds which converts the organic materials either to less toxic compounds or to harmless carbon dioxide and water.
It was observed with respect to the prior Garg et al process that the high silica zeolite adsorbents did not merely concentrate the organic substrates for subsequent oxidation, but appeared to exhibit a catalytic activity in promoting the reaction between the organic materials and the oxidizing compound. It was theorized that trace metal impurities in the molecular sieve material were responsible for the catalytic activity, and the intentional addition of metals with known catalytic properties, such as Group VIII metals, was proposed. More recent investigations involving the intentional incorporation of catalytic metals such as copper and iron into the molecular sieve have not established any marked affect upon the oxidation of adsorbed organic substrates.
SUMMARY OF THE INVENTION
It has now been found that the hydrogen ion concentration of the oxidizing regeneration medium is a major factor which affects the oxidation of the adsorbed organic substrate in the aforesaid Garg et al process. This is particularly so in those cases where the adsorbent is highly siliceous, i.e. has a framework SiO 2 /Al 2 O 3 molar ratio of greater than about 35. In general, the higher the hydrogen ion content (the lower the pH) the more complete the removal of carbonaceous compounds from the adsorbent during the oxidative regeneration procedure. pH values of less than 7 can be employed with values less than 5 being preferred. The minimum value selected is to some extent dependent upon the SiO 2 /Al 2 O 3 ratio of the molecular sieve involved. With highly siliceous molecular sieves such as the silica polymorphs, pH values as low as about 1.0 can be used to advantage, but in the case of zeolite molecular sieves having SiO 2 /Al 2 O 3 values of less than 12, severe to moderate degradation of the adsorbent can be experienced using pH value that low.
It has further been found that the Bronsted acid sites such as those associated with AlO 2 tetrahedral units of the molecular sieve structure also drive the oxidation reaction. Thus the use of molecular sieves having framework SiO 2 /Al 2 O 3 ratios in the range of 5 to 100, preferably 10 to 50, and being at least partly in the hydrogen cation form, preferably containing at least 20 equivalent per cent and more preferably at least 50 equivalent per cent hydrogen cations, provides a significant improvement either alone or in conjunction with the lowering of the pH of the regeneration medium.
DETAILED DESCRIPTION OF THE INVENTION
In a cyclic process for purifying aqueous media containing dissolved organic impurities which comprises providing an aqueous feedstock containing from about 5 ppb (wt.) to about 20,000 ppm (wt.) of dissolved organic compounds, contacting said feedstock with an adsorptive mass of an organophilic zeolitic molecular sieve, said molecular sieve having pore diameters large enough to adsorb at least some of said or9anic oompounds whereby said organic compounds are adsorbed thereon and a purified water product is obtained, and thereafter regenerating said molecular sieve and oxidatively destroying at least a portion of the organic adsorbate thereon by contact with an aqueous solution of a compound having a standard oxidation potential of at least 0.25 volt, and again contacting the regenerated molecular sieve with additional water to be purified, the present invention provides an improvement in accordance with one embodiment of this invention which comprises reducing the pH of the aqueous solution of the compound having a standard oxidation potetial of at least 0.25 volt during the period said solution is in contact with the molecular sieve being regenerated to a value of not greater than 7.
The liquid aqueous feedstocks suitably treated by the process of this invention are not critical as to their source. Ground water, industrial waste water streams, effluents from municipal sewage treatment facilities and the like are all suitable feedstocks provided they contain as a solute at least 10 ppb of organic impurities. It is not a critical factor whether the impurities are considered to be volatile or non-volatile. The organic contaminants most frequently found in well water include chloro-organics such as tetrachloroethylene, trichloroethylene, 1,1,1 trichloroethane, carbon tetrachloride, chloroform, monochlorobenzene, dichlorobenzenes, methylene chloride, benzene, toluene, xylenes, ethyl benzene, chlorodibromomethane, and dibromochloropropane, and can include organic cyanides, mercaptans and certain naturally occurring organics commonly referred to as "humics". Of course, in any particular location the water feedstock may contain any organic molecular species since essentially any organic material existing in nature or synthesized by man can ultimately find its way into the environment and then into a water source.
It is important to the operability of the present process that the molecular sieve adsorbent utilized has an adsorptive preference for the less polar organic materials with respect to water. As a general rule, the more siliceous the molecular sieve, the stronger the preference for non polar adsorbate species. In the case of zeolite molecular sieves such preference is usually observable when the framework molar SiO 2 /Al 2 O 3 ratio is at least 12, and is clearly evident in those zeolite species having SiO 2 /Al 2 O 3 ratios of greater than 30. A wide variety of zeolites can now be directly synthesized to have SiO 2 /Al 2 O 3 ratios greater than 50, and still others which cannot at present be directly synthesized at these high ratios can be subjected to dealumination techniques which result in organophilic zeolite products. High temperature steaming procedures involving zeolite Y which result in hydrophobic product forms are reported by P. K. Maher et al., "Molecular Sieve Zeolites," Advan. Chem. Ser., 101, American Chemical Society, Washington D.C., 1971, p. 266. A more recently reported procedure applicable to zeolite species generally involves, dealumination and the substitution of silicon into the dealuminated lattice site. This process is disclosed in U.S. Pat. No. 4,503,023 issued Mar. 5, 1985 to Skeels et al. Many of the synthetic zeolites prepared using organic templating agents are readily prepared in a highly siliceous form--some even from reaction mixtures which have no intentionally added aluminum. These zeolites are markedly organophilic and include ZSM-12 (U.S. Pat. No. 3,832,449) and ZSM 35 (U.S. Pat. No. 4,016,245) to name only a few. It has been found that the aspect of the present invention which involves the lowering of the pH of the regeneration medium is particularly advantageous when the adsorbent material employed comprises one of the silica polymorphs known as silicalite, F-silicalite, or TEA-silicate.
Though not, strictly speaking, zeolites, because of a lack of ion-exchange capacity, these molecular sieve materials are included within the terms zeolite or molecular sieve as used herein. These materials are disclosed in U.S. Pat. Nos. 4,061,724; 4,073,865 and 4,104,294, respectively. Not only are high silica zeolites organophilic, but it has also found that they are resistant towards crystal lattice degradation from contact with the strongly oxidizing compounds used to oxidatively degrade the organic impurities in the second (or regenerative) stage of the present process, and from the contact with the strongly acidic aqueous media. The reasons why the effects of high hydrogen ion concentration in the aqueous regeneration medium are more pronounced with respect to very highly siliceous molecular sieves have not yet been fully elucidated. It is possible, that the acid sites in the less siliceous molecular sieves function independently of the extraneous acidity and have a similar catalytic effect which masks the reaction mechanism involving the extraneous acidity. It is also possible, that the acidity of the regeneration medium directly affects and enhances the very few acid sites present in the highly siliceous molecular sieves. It has been observed that silica polymorphs, as a class, exhibit acidic catalytic activity far greater than would be expected in view of the near absence of AlO 2 framework tetrahedral units and the acid sites associated with such units.
The oxidizing agents used to regenerate the adsorbent have a standard oxidation potential of a least 0.25 volt, and preferably between 0.5 and 2.0 volts. Illustrative of compounds which have such oxidation potentials are the chlorates (ClO 3 - ), the hypochlorites (OCl - ), the permanganates (MnO 4 - ), the dichromates (Cr 2 O 7 -2 ) hydrogen peroxide (H 2 O 2 ). These compounds have the following respective standard oxidation potentials: 0.63 volt, 0.89 volt, 1.23 volts, 1.33 volts and 1.77 volts. Compounds having an oxidation potential greater than 2.00 volts, include the peroxy-sulfates and ozone. While very effective in oxidizing the organic substrates, the compounds with oxidation potentials greater than about 2.0 tend to cause some deterioration of the zeolite crystal structure. The above mentioned compounds can contain various cations in association with the specified anions. For instance, the compounds can be in the forms of metal salts, such as the alkali metal salts, or even ammonium salts. The sole criterion being that the oxidation potential of the compound be at least 0.25 volt. As utilized to contact the organic-loaded zeolite adsorbent, the oxidizing compounds are most commonly in the form of aqueous solutions.
As in the case of the prior Garg et al. process discussed above, the concentration of the oxidant in the regeneration medium is not narrowly critical. It has been found, however, that increasing the hydrogen ion concentration results in a much more efficient utilization of the oxidant. The concentration of H 2 O 2 in the regeneration medium in the prior Garg et al process was preferably in the range of 10 to 50 weight percent, and most preferably from 20 to 40 weight percent, and was employed in amounts 10 to 15 times the stoichiometric requirements. With the pH adjustment of the present invention, it is possible to regenerate a silicalite adsorbent with an H 2 O 2 aqueous solution containing only 3 to 5 weight percent H 2 O 2 and using quantities only 2 to 5 times the stoichiometric amount. This finding has considerable significance in that oxidant solutions in very high concentrations can be somewhat hazardous to handle, whereas low concentrations are relatively quite safe to utilize. Hydrogen peroxide solutions in the range of 3 to 5 percent by weight are common in ordinary household products. Accordingly, oxidant concentrations in the regeneration media used in the present process are preferably in the range of 1 to 30 weight percent and most preferably, especially in the case of H 2 O 2 , of 2 to 7 weight percent. Concentrations of from about 1 to 90 weight percent can be used. Optimum quantities and concentrations depend to some degree upon the particular molecular sieve adsorbent employed, the temperature and the period of time permitted for the regeneration step. Contact periods of from 0.5 to 72 hours are suitably used at temperatures of from 0° C. to 65° C., with ambient conditions, i.e. 10° C. to 30° C., being preferred.
In carrying out the process, the adsorption and regeneration procedures are typically accomplished by passing the feedstock to be treated and the oxidizing regenerate through a packed or fixed bed of the adsorbent. The process can, however, be carried out in a number of other arrangements common to the adsorption and water treatment art. For example, the adsorbent can be slurried in the water to be detoxified, removed therefrom by filtration, decantation, centrifugation or the like and regenerated by again being slurried in the oxidizing solution. For continuous operation, a treatment system involving at least two fixed beds of zeolite adsorbent is advantageously employed so that regeneration of spent beds can be conducted while other fresh beds are engaged in the adsorption-purification stage. Four distinct process schemes are disclosed hereinafter, each having advantages depending upon the type of organic adsorbate involved and the simplicity of equipment desired.
THE DRAWINGS
FIG. 1 is a schematic flow diagram illustrating an embodiment of the present invention of the so-called "batch soak" concept.
FIG. 2 is a schematic flow diagram illustrating an embodiment of the present invention utilizing a closed loop type of bed regeneration.
FIG. 3 is a schematic flow diagram illustrating an embodiment of the present invention utilizing an open loop type of bed regeneration with an auxiliary catalytic bed.
FIG. 4 is a schematic flow diagram illustrating an embodiment of the present invention utilizing a continuous type of bed regeneration.
The various process embodiments of the present invention are illustrated below with reference the various figures of the drawings.
With reference to FIG. 1, the following procedure is carried out:
Adsorption beds 10 and 12 are packed with silica bonded silicalite particles. Feedstock water containing 200 ppm organic impurities is passed into the system through line 14, valve 16 and line 18 into the top of bed 10. During passage through bed 10 the organic content of the feedstock is selectively adsorbed on the silicalite, with the organic mass transfer zone passing downward and purified water leaving the bed through line 20, valve 22 and line 24. The adsorption is continued until just prior to breakthrough of the organic mass transfer zone, and the feedstock is then diverted to bed 12 through valve 16, line 26, valve 28 and line 30. Bed 12 has, during the period bed 10 was on adsorption, been regenerated after a previous adsorption stage therein by the following procedure: After the flow of feedstock through line 30 has been terminated, bed 12 is drained through line 32, valve 34 and line 36, and thereafter an aqueous solution of oxidizing compound such as H 2 O 2 , to which sulfuric acid has been added to lower the pH to a value of about 3, is introduced into the system through line 38 and is fed by means of pump 40 through line 42, heater 44, line 46, valve 50 and 52 downward into bed 12. After bed 12 has been filled with the acidified oxidant solution at the optimum temperature, the bed is held quiescently for a period sufficient to oxidize the organic adsorbate, at least in large part, to CO 2 and H 2 O. After the desired degree of oxidation of the organic substrate, the bed is drained through line 32, valve 34 and line 36, and optionally is flushed with a diverted portion of the feedstock through valve 16, line 26, valve 28 and line 30. Thereafter the purification stage in bed 10 is terminated and regeneration therein is begun by passing oxidizing solution through valve 50, line 56, and valve 58, and feedstock water is fed into bed 12 through line 14, valve 16, line 26, valve 28 and line 30. Purified water is removed from the system through line 60, valve 62, valve 22 and line 24.
The relatively simple procedure illustrated by FIG. 1 is advantageously utilized when the loading of organic adsorbate on the molecular sieve is low or is a compound in which carbon is a small percentage of the total molecular weight. Under these conditions a relatively small amount of oxidant is required to oxidize the organic material. When loadings are high or contain a high percentage of carbon atoms, the oxidant required for complete oxidation is greater than the quantity which is contained in one bed volume of regeneration medium, and complete oxidation cannot be accomplished with a single batch soak. The method can readily be adopted for multiple soak periods, however.
With respect to FIG. 2, the closed loop regeneration system shown schematically therein uses an external tank 54 to hold the amount of oxidant medium required for complete regeneration of the adsorption beds 55 and 56 and the complete oxidation of the adsorbed organic containment. Each of beds 55 and 56 contain 521 grams of silicalite adsorbent. An aqueous feedstock containing 150 ppm (wt.) toluene is fed into the system through line 57, valves 58 and 59 and into bed 55. Toluene is adsorbed on the silicalite adsorbent and the purified water is removed from the system through valve 60 and line 61. Bed 56 which contains adsorbed toluene from the previous adsorption purification cycle is regenerated while bed 55 is undergoing adsorption. To accomplish regeneration of bed 56, flow of regeneration medium from tank 54, which contains 5800 cc of a 5 wt. % hydrogen peroxide solution at a pH of 2.5 passes through line 62, heater 63, pump 64, line 65 and valve 66 into the bottom of bed 56. Partially spent regeneration fluid passing out of bed 56 was recirculated back to tank 54 through line 68, valve 69 and line 70. The solution was recirculated in the foregoing fashion for 275 minutes. During that period, the concentration of toluene that had been desorbed into the peroxide solution decreased from 397 ppm to 6 ppm, indicating that the toluene was being oxidized as it recirculated through the adsorbent in bed 56. To test bed 56 for thoroughness of regeneration, an aqueous solution of 200 ppm toluene was passed into the bed and the bed effluent analyzed for toluene. After one hour the effluent contained 1.0 ppm toluene, and after two hours the toluene concentration was less than 10 ppm. Flowrate and analytical data on the bed effluents at specific times are set forth below in Table I.
TABLE I______________________________________Regeneration EffluentTIME Flowrate Toluene H.sub.2 O.sub.2(Min) (cc/min) (ppm) (wt. %)______________________________________ 20 54 27 3.7 65 35 397 1.4125 80 36 2.8155 78 18 2.5185 80 38 2.3275 110 6 1.8______________________________________2nd Cycle Adsorption - 200 ppm Toluene Feed EffluentTime Flowrate Toluene(min) (cc/min) (ppm)______________________________________ 8 98 0.6 30 86 0.8 60 125 0.9120 120 9.1200 126 33265 122 100360 128 195______________________________________
The process system illustrated with reference to FIG. 3 includes an open loop regeneration system combined with a catalytic bed in which the oxidant-containing medium is passed only once through the adsorption bed being regenerated. Any organic materials desorbed from the bed but not oxidized, are entrained in the effluent regeneration. medium and thereafter passed through an auxiliary bed containing molecular sieves which catalyzes and completes the oxidation process before the unreacted organic can leave the system. As in the case of the closed loop regeneration system, the open loop system of FIG. 3 uses an external tank 71 to hold the oxidant medium required for regeneration of adsorption beds 72 and 73. The organic-containing aqueous feedstock enters the system through line 74 and passes through valve 75 into adsorption bed 72. Purified effluent water leaves the system through line 76 valve 77 and line 78. To regenerate the adsorbent in bed 77 oxidant medium flows from tank 71 through line 79, pump 80, line 81, valve 82, line 83 and line 76 into the top of bed 72. A portion of the organic adsorbate is oxidized on the adsorbent and a portion is desorbed in an unreacted state and leaves bed 72 in the bed effluent which passes through valve 79 and line 80 into bed 81 which contains a catalyst, such as a molecular sieve having a relatively large number of acidic sites, which catalyzes the residual organic content of the effluent from bed 72 to compounds harmless to the environment. It should be noted that if a molecular sieve is chosen as the catalyst for use in auxiliary bed 81, adsorption capacity is of little importance. For that reason the molecular sieve need not even be hydrophilic, but ideally a balance should be made between hydrophilicity, number of acid sites, and structural stability in the oxidative medium.
The open loop catalytic bed system is advantageously used in applications where recirculation of the regeneration solution is undesirable. For instance, chlorinated hydrocarbons, when oxidized will produce chloride ions and hydrochloric acid which is very corrosive toward stainless steel. In closed loop regeneration, the acid would tend to accumulate as the oxidation progressed, leading to corrosion of pipes and vessels of the system.
A system which utilizes a continuous type of bed regeneration is illustrated with reference to FIG. 4. This embodiment involves injecting an oxidant medium into the adsorption bed, intermittently or continuously, advantageously into the aqueous stream being treated for organic removal as it enters the adsorbent bed. Organic substrates already adsorbed on the sieve are oxidized and converted to harmless products thus making available sites on the molecular sieve to adsorb incoming contaminant molecules. The continuous regeneration process requires only a single adsorbent bed since oxidation and adsorption occur simultaneously and the bed never becomes saturated with contaminant. As used herein, the term "continuous" refers to the regeneration, i.e. the oxidation reaction and not to the injection of oxidant into the bed. A preferred mode of operation of the continuous regeneration method is the periodic or "pulsed" addition of oxidant to the aqueous feedstock entering the bed, or injection directly into the bed, only so often as is required to maintain sufficient adsorption sites on the molecular sieve adsorbent to ensure removal of the organic contaminants to the desired degree. Thus regeneration which is adequate to maintain the functioning of a particular adsorbent bed for periods greater than would occur in the total absence of regeneration is deemed to be continuous for purposes of the present specification and the appended claims.
The operation of the continuous regeneration treatment process of this invention is demonstrated by the following experimental procedure. With respect to FIG. 4, a continuous feedstock of water containing 50 ppm of toluene is fed into the system through line 82 and valve 83 into bed 84 containing about 0.5 gram of silicalite as the adsorbent. The feed rate of the stream to be treated was 5 ml./min. Purified water containing no detectable amount of toluene was recovered from line 85. An aqueous hydrogen peroxide solution containing 30% H 2 O 2 contained in tank 86 was injected by means of pulse timer 90 through line 87, valve 88, line 89 and valve 83 in 1.0 ml. quantities at one half hour intervals into the feedstock entering from line 82. To enhance the oxidation reaction, the bed 84 was externally heated prior to each pulse of H 2 O 2 solution. No toluene was detectable in the bed effluent through line 85 over the period of about the first 70 minutes. The data collected for the period of 133 minutes is set forth in Table II, below.
TABLE II______________________________________ Effluent Bed Out- Cumulative Toluene, let Temp,Time Time, Min ppm °C. Remarks______________________________________ 9:34 22 Start 9:50 16 ND 23 9:54 23 Heat on 9:55 37 9:56 50 9:57 65 9:58 24 ND 7110:02 64 Add 1 ml 30% H.sub.2 O.sub.210:05 65 Heat off10:13 39 ND 2710:22 48 ND 2410:25 Heat on10:26 52 ND 4410:36 66 Add 1 ml 30% H.sub.2 O.sub.210:32 63 Heat off10:45 71 ND 2510:52 78 <1 2510:56 25 Heat on10:57 83 2 4011:00 69 Add 1 ml 30% H.sub.2 O.sub.211:02 69 Heat off11:20 106 <1 2511:27 113 4 25 Heat on11:31 71 Add 1 ml 30% H.sub.2 O.sub.211:34 63 Heat off11:40 33 Feed concentration = 34 ppm11:43 129 ND 2711:47 133 Stop______________________________________ ND = not detectable.
For purposes of comparison, the process was repeated except that no oxidant was pulse injected into the feedstock entering the adsorption bed 84. The results are summarized in Table III below, establishing that toluene was detected in the effluent water stream through line 85 after 15 minutes, had risen to 11 ppm after 76 minutes, and to 29 ppm at 136 minutes.
TABLE III______________________________________ Cumulative Effluent TolueneTime Minutes (ppm)______________________________________8:34 0 (start)8:43 9 ND8:49 15 <18:54 20 <19:00 26 <19:05 31 19:10 36 29:30 56 69:50 76 1110:10 96 1810:30 106 2311:00 136 29Feed 51______________________________________
It will be understood that the process embodiments illustrated in conjunction with the Figures of the drawings can be operated using as the adsorbent any molecular sieve which is organophilic, particularly the zeolite molecular sieves having SiO 2 /Al 2 O 3 molar ratios in the range of 12 to 2000, and the regeneration carried out using an oxidant medium in which the pH has either been lowered or remains unadjusted.
The following experimental procedures were carried out to illustrate the effects of pH adjustment upon the temperature, time and oxidant concentration requirements for regenerating both highly siliceous and moderately siliceous adsorbents have loadings of various organic substrates. The various adsorption tests were run by placing 5 grams of the adsorbent to be tested into a clean one-pint jar and then adding the organic-containing aqueous test composition. The jars were then capped loosely and placed in a shaker bath at ambient temperature for 24 hours. The samples were then removed from the bath, the liquid phase decanted and the solid phase rinsed with 50 ml. of distilled water. A 0.5 gram portion of the solid phase was removed from the jar and analyzed for total carbon. To the jar containing the solid phase, a hydrogen peroxide solution of the desired strength and in the desired amount was added. In appropriate cases the peroxide solution was pH adjusted using either an acid or a base. The jar was loosely capped and placed in a shaker bath for up to 24 hours at the desired temperature. A portion of the liquid phase was retained for analysis to determine residual hydrogen peroxide content. The solid phase was rinsed with 50 ml. of distilled water and analyzed for total carbon. Two types of adsorbent were utilized, namely (a) silicalite, a silica polymorph prepared with no intentionally added alumina and having a SiO 2 /Al 2 O 3 ratio of at least 300, and (b) a zeolite having a crystal structure topologically related to silicalite but being synthesized in the absence of an organic templating agent and having a SiO 2 /Al 2 O 3 ratio of about 40. (see U.S. Pat. No. 4,257,885). This latter zeolite is identified hereinafter as LZ-105-6 and was utilized in the hydrogen (partially decationized) form. The results of the various tests are reported below in Tables IV, V, VI and VII.
TABLE IV______________________________________ % CExp. pH Ads. pH Regen. After After % C# Initial Final Initial Final Ads. Regen Removal______________________________________1 5.5 9.0 5.5 3.0 3.2 0.54 83 2* 5.5 -- -- -- 1.2 0.25 793 5.5 6.8 5.5 4.7 1.2 0.23 814 5.5 9.0 3.0 1.8 3.1 0.16 955 5.5 9.0 5.5 6.9 3.2 1.10 666 5.5 9.0 9.0 9.6 3.1 2.00 35______________________________________ *An exothermic reaction to 120° F. Sample taken after exotherm subsided, -1 hour. All samples were regenerated using 40 ml. of 30% H.sub.2 O.sub.2
In the foregoing experiments, the adsorbent in Nos. 1, 4, 5, and 6 was silicalite and in Nos. 2 and 3, LZ-105-6. The following pH adjustment to the regeneration medium was made:
______________________________________Experiment No. Treatment______________________________________1 None2 None3 None4 Ph adjusted to 3 with 25% H.sub.2 SO.sub.45 1 cc. of 0.25 M ferrous sulfate added6 pH adjusted to 9.0 using NH.sub.4 OH______________________________________
TABLE V______________________________________EFFECT OF pH ADJUSTMENT pH H.sub.2 O.sub.2 % °C.Exp. Ad- Strength Re-# Product Type just %* Organic Temp moval______________________________________ 7 Silicalite No 30% (13) Phenol 150 83 8 Silicalite Yes 30% (13) Phenol 150 95 9 Silicalite No 30% (10) TCP 150 1910 Silicalite Yes 30% (10) TCP 150 9611 LZ-105-6 (Al) Yes 5% (5) Phenol Amb. 8712 LZ-105-6 (Si) Yes 5% (4) Phenol Amb. 8213 LZ-105-6 (Si) No 5% (11) TCP/ Amb. 69 Toluene14 LZ-105-6 (Si) Yes 5% (17) TCP/ Amb. 72 Toluene______________________________________ *Numbers in parentheses are number of times stoichiometric excess with respect to carbon present. TCP = Trichloropropane (Al) = Alumina bonded pellets (Si) = Silica bonded pellets
TABLE VI______________________________________EFFECT OF TIME, TEMPERATURE, H.sub.2 O.sub.2 STRENGTH pH H.sub.2 O.sub.2Exp. Ad- Temp. Time Strength % °C.# Product Type just °F. (Hrs) %* Removal______________________________________15 Silicalite No 150 24 30 (14×) 9816 LZ-105-6 (Si) Yes Amb. 24 5 (2×) 9217 LZ-105-6 (Si) Yes Amb. 24 3 (2×) 8018 LZ-105-6 (Si) Yes Amb. 4 5 (2×) 8219 LZ-105-6 (Si) Yes Amb. 8 5 (2×) 8920 Silicalite Yes 150 24 5 (2×) 8221 Silicalite Yes Amb. 24 5 (2×) 26______________________________________ *Numbers in parentheses are number of times stoichiometric excess with respect to carbon present. (Si) = Silica bonded pellets
As is evident from the foregoing investigations, it has further been found that the reduction of the pH of the oxidizing regeneration medium is not the only means for increasing the catalytic activity of the molecular sieve adsorbent in the purification process. When the hydrogen cation forms of zeolites and other molecular sieves having SiO 2 /Al 2 O 3 molar ratios of from about 12 to about 100, preferably from about 20 to about 80 are utilized for the adsorption of organic contaminants from aqueous streams, the acidic sites of the zeolites per se, i.e. without the necessary presence of an extraneous acid, are capable of significantly promoting the oxidation of the adsorbed organic substrate when contact with an oxidant having an oxidation potential of at least 0.25 volt, such as hydrogen peroxide or other peroxides. This is made quite clear by the data of Experiment 2 above. The LZ-105-6 adsorbent had been employed to adsorb phenol from a 1% aqueous solution thereof. In attempting to carry out the regeneration using 40 ml. of 30% H 2 O 2 solution, a vigorous reaction occurred upon contacting the loaded zeolite with the regeneration medium at ambient room temperature resulting in an exotherm to 120° F. The phenol removal at "ambient" temperature for LZ-105-6 was found to be 79% versus 83% for regeneration of silicalite at 150° F. with the same adsorbed substrate and the same peroxide solution (Exp.1). Similar results were obtained when trichloropropane (TCP) was the adsorbed substrate. Results are shown in Table VII below.
TABLE VII______________________________________ H.sub.2 O.sub.2 % °C. %Exp. Si/Al Strength Re- Oxi-# Product Type Ratio %* moval Temp dation______________________________________22 LZ-105-6 40 3% (2×) 84 Amb. 97(Al)23 LZ-105-6 40 5% (2×) 85 Amb. 89(Al)24 Silicalite 300 5% (2×) 62 150° F. 66______________________________________ *Numbers in parentheses are number of times stoichiometric excess of H.sub.2 O.sub.2 with respect to carbon present. (Al) = Alumina bonded pellets | In the process for removing organic impurity constituents from aqueous media by adsorbing same on an organophilic molecular sieve adsorbent, followed by regeneration of the adsorbent by contact with an oxidant, such as hydrogen peroxide, whereby the organic adsorbate is converted to innocuous materials, principally CO 2 and H 2 O, the efficiency of the regeneration operation is found to be substantially improved by decreasing the pH of the regenerating medium and/or increasing the number of Bronsted acid sites in the molecular sieve adsorbent. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 10/200,115, filed on Jul. 23, 2002 now U.S. Pat No. 6,960,929, which, in turn, is based on and derives the benefit of U.S. Provisional Patent Application Ser. No. 60/306,880, filed on Jul. 23, 2001. The entire contents of Ser. No. 10/200,115 and Ser. No. 60/306,880 are incorporated herein by reference.
This invention was made with government support of Job No. 768, of the National Security Agency. The government may have certain rights in this invention.
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to superconductive switching devices, and in particular to a superconducting crossbar switch for bi-directionally connecting a plurality of inputs with a plurality of outputs.
Background of the Technology
Advances in high performance computing are being pursued in many different directions. The technology thrust has been directed toward very high speed, high circuit density chips which are of low power (to permit small volume packaging) and organized into a small number of processors. Another thrust involves the use of many processors, tens to perhaps thousands, working in concert to perform the computation. In this case, the stress on the individual elements is relieved and there is greater computational power, but interconnection problems that arise with the added software complexity must be solved.
One of the configurations for a massively parallel computing system calls for a large number of processors to be connected to a large shared memory system on an equal access basis. The demands placed upon the interconnection switch are formidable, in terms of complexity, speed, and intelligence. For example, the switch must have a short latency time and must establish the requested connection very quickly, ideally within a small fraction of the processor clock time. The data rate per channel must also be very high. For example, for a 32 bit word machine with a 30 nanosecond clock, a data rate of 10 9 bits/second (i.e., gigabits/second) per processor is required. Once established, the data path must be immune to noise, and crosstalk must be kept to a minimum. The established link must be inviolate during the processor transaction time and releasable very quickly, ideally within a clock cycle.
There is a need to inform the processor of successful connection. The time during which two or more processors contend for the same memory port needs to be minimized with fast resolution of these contentions. Finally, data needs to be transferred in both directions. Although there are a number of switch architecture solutions, it is generally accepted that the best solution is a crossbar, which is a switch that allows the requesters equal access at the same level to any output line.
Computer systems also need high bandwidth and short access times to carry out data exchange between memory and processors, and among processors.
Related Art
Crossbar switches are well-known in the prior art, as evidenced by U.S. Pat. No. 3,539,730 to Imamura, which discloses a crossbar switch used in a two-stage link connection system. Each switch is divided into two parts, in accordance with vertical groups. The parts of the switch are assigned to primary and secondary lattices, respectively, with links between the lattices being formed by connecting the outgoing lines from the primary lattice of one switch with the secondary lattice of another switch.
Also known in the art are polarity switching circuits which utilize Josephson junction devices (e.g., interferometers) and superconducting interconnections coupled to a utilization circuit, including one or more memory cells or logic circuits. Such circuits are disclosed, for example, in U.S. Pat. No. 4,210,921 to Faris.
Prior switching circuits possess certain inherent drawbacks that render them unsuitable for use with large numbers of computing elements. As a result, they cannot meet all of the requirements set forth above for a massively parallel computing system.
SUMMARY OF THE INVENTION
The present invention overcomes the above identified drawbacks of the prior switching circuits, as well as others, by providing a modular crossbar switch that is extendable in size, operates under low power with low latency, and detects and resolves conflicts that arise when two or more processors contend for the same memory port. The switch of the present invention is capable of interconnecting N computers or processors with M memories, or other processors or computers where N and M can be of the order of 1000 or more. One embodiment of the present invention is also modular, in that small crossbars can easily be extended to become very large ones, (e.g., 32×32 can grow into 1000×1000). In addition, if the computer data rate exceeds that of one channel, paralleling of channels is easily performed. The switch is also suitable for general communications network usage, as well.
An embodiment of the present invention includes a crossbar switch for connecting a plurality of input devices with a plurality of output devices, and a switching cell having an input, an output, and an apparatus for connecting the output for bi-directionally transmitting data there between. The connecting apparatus includes a superconductive device having zero resistance and negligible crosstalk, and a control device to control operation of the connecting apparatus. The connecting apparatus provides a connection for a plurality of processors or functional units to be connected to one another. For example, a configuration of adders, multipliers, and dividers can be switched, such that data can be routed sequentially from one function to another with arbitrary freedom.
Another embodiment of the present invention includes a second superconductive device and a second control device to retain and release the operation of the first superconductive device.
An additional embodiment of the present invention includes a plurality of inputs, a plurality of outputs, and a plurality of cells arranged in a matrix, with the inputs coupled to one plurality of cells and the outputs connected to another plurality of cells, so as to define a superconducting device matrix. In an embodiment of the present invention, the cells are connected in parallel with the inputs and outputs.
In a further embodiment of the present invention, each output includes a summing device for summing output voltages or currents of the cells connected therewith, in order to accommodate the inputs and to render the matrix extendable in numbers of inputs and outputs.
The summing device may include a summing amplifier or an additional superconductive device.
In another embodiment of the present invention, the switching cells include a feedback mechanism connected to the outputs which feeds data to the outputs and acknowledges pulses back to a requester.
In yet another embodiment of the present invention, retaining and releasing devices for the cells are connected to the outputs and are interconnected and operable to simultaneously retain a selected cell of the plurality of cells, and disable the remaining cells of the plurality of cells, whereby a subsequent query on a disabled cell is inoperative until the selected cell is released. The crossbar also allows multicast or broadcast operation wherein any one input may be connected simultaneously or in arbitrary order to more than one or all of the output ports.
In a further embodiment of the invention, a sensing apparatus is connected with each of the outputs for detecting simultaneous queries to cells of the respective groups of cells and for generating to the processors via the cells an indication of conflict from the simultaneous queries as well as resolving these conflicts while preventing further interference.
Additional advantages and novel features of the invention will be set forth in part in the description that follows, and in part will become more apparent to those skilled in the art upon examination of the following or upon learning by practice of the invention.
BRIEF DESCRIPTION OF THE FIGURES
In the drawings:
FIG. 1 illustrates a prior art Josephson junction device;
FIG. 2 is a graph illustrating the operation of the Josephson junction device of FIG. 1 ;
FIG. 3 is a simplified perspective view of a prior art Josephson junction device with a magnetic field control line;
FIG. 4 shows prior art operation of Josephson junctions in which a resistor is placed between the electrode and the counter-electrode for the device shown in FIG. 1 ;
FIG. 5 is a schematic representation of a prior art Superconducting Quantum Interference Device (SQUID) device;
FIG. 6 is a graph representing the operation of the SQUID device of FIG. 5 ;
FIG. 7 illustrates a matrix of cells comprising a superconductive crossbar switch, in accordance with an embodiment of the present invention;
FIGS. 8 and 9 illustrate use of the superconductive crossbar switch, in accordance with an embodiment of the present invention;
FIGS. 10 and 11 illustrate use of the superconductive crossbar switch, connected to a summing device, in accordance with an embodiment of the present invention;
FIG. 12 is a schematic representation of a switch illustrating a plurality of summing devices, and the clamping and crossbar cell memory circuit, in accordance with an embodiment of the present invention;
FIG. 13 is a schematic representation of the cell circuits and clamp circuit and their operation in the situation of no contention, in accordance with an embodiment of the present invention;
FIG. 14 is a flow diagram illustrating operation of the circuits of FIG. 12 , in accordance with an embodiment of the present invention;
FIG. 15 is a timing diagram illustrating the operation of the circuits of FIG. 13 , and a situation of non-simultaneous request (no contention) for a memory line, in accordance with an embodiment of the present invention;
FIG. 16 is a schematic representation of the cell circuits in the situation of two simultaneous requests for the same memory line, in accordance with an embodiment of the present invention;
FIG. 17 is a timing diagram illustrating the operation of two processors contending for the same output line, in accordance with an embodiment of the present invention;
FIG. 18 illustrates a representative physical layout of a 128×128 crossbar switch, in accordance with an embodiment of the present invention; and
FIG. 19 illustrates a representation of a crossbar switch chip, including separate decoders and the switching matrix, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a Josephson tunnel junction device known in the prior art. The Josephson tunnel junction device includes top and bottom layers 20 , 21 of superconductor material sandwiching a thin insulating film 22 . If a voltage V is applied between the top and bottom layers through a resistance R, there is a range of current in which zero resistance current up to I m , can be transported between the two elements.
FIG. 2 illustrates the behavior of the circuit current I as the input voltage V is increased for a representative resistance R, in the Josephson tunnel junction device shown in FIG. 1 . The voltage V j across the device will be zero until the device current exceeds I m , at which point the junction will switch to the voltage state consistent with the circuit load resistor R and the device's own voltage-current curve J, determined by the physics and manufacturing art.
FIG. 3 illustrates a Josephson junction device 29 known in the prior art, in which switching occurs by imposing a magnetic field into a junction via a control line placed above it. The current I to be controlled is carried through a first layer of superconducting material 30 on a substrate 31 . A thin film of insulator 32 separates the first superconducting material 30 from a second layer of superconducting material 33 . An insulator layer 35 separates layer 33 from a third layer of superconducting material 36 . When a control current I c , passes through layer 36 , a magnetic field 37 is created at the junction, which reduces the maximum allowed zero resistance current. Thus, if the device's transport current I is greater than the new allowed value, the device will switch into the voltage state, similar to as described above with regard to FIGS. 1 and 2 . The device can be fabricated to switch with picosecond rise times, with its final voltage state in the millivolts range for presently available materials. The currents that are switched are most often in the hundreds of microamperes range. The power dissipation per unit is in the microwatt range.
The prior art also includes fabrication of Josephson Junctions in which the device has the current versus voltage curve represented by FIG. 4 , as compared with FIG. 2 . This behavior may be acquired by a resistor being placed between the electrode and the counter-electrode of the device in FIG. 1 . Or, equivalently, one may achieve such a “weak link” behavior by fabricating the Josephson device with a conductor between the two electrodes of FIG. 1 . It is also well known that such behavior is a standard property of so-called “high temperature” superconductive Josephson Junctions. The effect of such a device is to provide a voltage, when switched, which is dependent upon the resistors in the circuit. Nevertheless, the circuits required can still be made from such junctions.
If one connects a Josephson junction in parallel with an inductance, the closed loop forms a Superconducting Quantum Interference Device (SQUID), which is also known in the prior art. Insertion of a second junction into this loop, as illustrated in FIG. 5 , also produces a SQUID, but with device properties that are very advantageous in switching applications. In particular, if an input current I g is inserted and divided between the two junctions, J 1 and J 2 , that zero resistance transport current can be controlled by introducing magnetic flux into the closed loop via the control current, I c . FIG. 6 shows the curve of allowed zero resistance current, I g , as a function of the imposed control current, I c . I m represents the maximum gate current I g as a function of the control current I c . In particular, if an input current I g is inserted, it will be divided into two paths according to the size of the inductors L 1 , and L 2 and the maximum critical currents of J 1 and J 2 , as well as by the control line current I c , which is magnetically coupled to the loop. FIG. 6 represents the joint values of I g and I c , for which current I g can be transported through the loop with zero resistance. This region is represented by the shaded area. Joint values of I g and I c , which are above this area, will result in non-zero voltage transport of I g . A control line can thus be used to change the maximum zero resistance current of a two terminal Josephson junction, or SQUID. The detailed properties depend upon the inductance, critical currents of the device, and insertion point(s) of the currents. (A more detailed explanation of the structure and operation of the Josephson junction and the SQUID is found in the IBM Journal of Research and Development, vol. 24, No. 2 (March 1980), which is hereby incorporated by reference.)
Superconductive Crossbar Switch
FIG. 7 illustrates a superconductive crossbar switch, in accordance with an embodiment of the present invention. The superconductive crossbar switch 39 includes at least one cell 41 in a matrix, which are arranged in rows and columns in accordance with the number of input lines I i 40 and output lines O i 43 . For example, there are N inputs and M outputs for coupling, such as via or including wired, wireless, or fiberoptic connections, N processors with M memories. The number of inputs and outputs need not be equal. In one embodiment of the present invention, the superconductive crossbar switch 39 is extendable to accommodate large numbers of processors and memories. Thus, for example, the module can easily be extended from a 32 input×32 output to a 1024 input×1024 output configuration, as is further described below.
Each input port connects to a row of cells 41 via an input line I i 40 . Each cell 41 includes a connecting circuit 44 , which connects the input line I i to a selected output line O i for bidirectionally transmitting data therebetween. The connecting circuit includes a first superconductive device 42 , which has zero-resistance. A first control signal applied to a first terminal 45 controls the first superconductive device 42 externally on command, for controlling operation of the superconductive crossbar switch 39 . In one embodiment, the first control signal comprises an electrical current.
Each cell 41 also includes a retaining and releasing circuit for retaining (i.e., clamping) and releasing the operation of the first superconductive device 42 . The retaining and releasing circuit includes a second superconductive device 46 and a second control signal, delivered through a clamp line 49 at a second terminal 47 , for controlling the second superconductive device 46 and the devices 46 of the cells 41 in the same column of cells 41 , as shown in FIG. 7 .
The first and second superconductive devices 42 and 46 can also be addressed by optical illumination, in another embodiment of the present invention. For example, if the first superconductive device 42 is optically illuminated, the switch cell connection from input to output will be maintained for the duration of the optical signal. In effect, the optical beam has “enabled” the desired connection. If the second superconductive device 46 is addressed by the optical beam, the current will be steered into the control line for the first superconductive device 42 . Alternatively, an electron beam could be used instead of an optical beam.
When the cells 41 are arranged in a matrix as shown in FIG. 7 , each input line I i 40 is coupled to a cell 41 (e.g., a row of cells), thereby to define a matrix of cells.
Method of Using the Superconductive Crossbar Switch
FIGS. 8 and 9 illustrate use of the superconductive crossbar switch 39 , in accordance with an embodiment of the present invention. Referring to FIG. 8 , the processors and memories coupled to the input lines 40 (I i =I 4 , I 5 , I 6 ) and output lines 43 (O i =O 8 , O 9 , O 10 ), respectively, need not be synchronously clocked, but instead may be run independently. The operation will be described for the example of a 32 input×32 output crossbar chip organized as shown in FIG. 8 , but it should be understood that any number of inputs 40 and outputs 43 may be provided. In this example, each of the 32 input lines from the 32 processors transmits a serial bit stream. The first serial bit word, or part of it, from a processor (or other source), contains the address of the specific memory line which the processor is attempting to acquire. In addition, the address bits are followed by a “FLAG” bit, a “one.” This first word carrying the destination address and the FLAG bit is input to the requesting processor's data line. The decoder selects the appropriate 1 st control line ( 45 a ) and powers it, thereby permitting the FLAG bit to proceed to the output line.
The initial state of each cell is a zero current condition in the first address terminals 45 a , 45 b , 45 c , and 45 d , corresponding to the first terminal 45 in FIG. 7 . As there is no current in the address lines, all the devices 42 a , 42 b , 42 c , and 42 d will short the processor pulses on input lines 40 to ground and therefore no output is observed at output lines 43 .
If now the processor coupled to input line I 4 attempts to access the memory coupled to output line O 8 , the process of FIG. 9 is followed. The processor decoder selects the address line for the output line O 8 , contained in the processor's request word (step 905 of FIG. 9 ). After the address line is found (decoded), it is determined if there is a control current for the address line (step 910 of FIG. 9 ).
If there is a control current (step 910 of FIG. 9 ), a decoder current is impressed at terminal 45 a , which depresses the zero resistance current threshold of superconductive device 42 a , thereby allowing input pulses to be transferred across the superconductive device 42 a (step 915 of FIG. 9 ). Subsequent pulses from the processor or input line 14 are then fed into the output line O 8 , and thus, for example, into a summing circuit 50 .
If there is no control current for the address line (step 910 of FIG. 9 ), the input pulses on input line I 5 are not transferred to output line O 8 (step 920 of FIG. 9 ), but are shorted to ground by the superconductive device 42 b , as shown in FIG. 8 . Thus, the input pulses from another processor do not interfere with the data pulses from input line 14 on output line O 8 .
Correspondingly, if, for example, input line I 5 seeks to send data to output line O 9 , then a current is impressed at terminal 45 d by the processor decoder and the input data pulse stream is then imposed upon output line O 9 , with no interference from the processor coupled to input line 14 because its control line 45 b is not driven.
Superconductive Crossbar Switch Coupled to Summing Device
FIGS. 10 and 11 illustrate use of an example superconductive crossbar switch 39 coupled to a summing device 68 , in accordance with an embodiment of the present invention. Referring to FIG. 10 , each cell 41 is similar to the cells 41 shown in FIG. 8 . In addition, each output line 43 is coupled to a summing device 68 containing a third superconductive device 51 controlled by the control line 65 . An input driver circuit 52 couples each input line to its corresponding processor.
FIG. 11 illustrates an exemplary process for using the superconductive crossbar switch 39 , coupled to a summing device 68 , as shown in FIG. 10 . In FIG. 10 , pulses a from the processor drive additional superconductive devices 55 into the voltage state and thereby impress a voltage on the input line 40 (step 1105 of FIG. 11 ), which is coupled to all the row cells accessed by that processor. The impressed voltage causes a current to flow through the resistor 57 to be shorted to ground via the first superconductive device 42 (step 1110 of FIG. 1 ).
It is determined if the control signal provided at terminal 45 is powered (step 1115 of FIG. 11 ). If yes, that control signal can be made sufficient to reduce the critical current through first superconductive device 42 , such that it exhibits a “gap” voltage (step 1120 of FIG. 11 ). The pulse current passing through the first superconductive device 42 will exceed the maximum zero resistance current and the first superconductive device 42 will switch into the voltage state, thereby impressing its “gap” voltage upon the cell tie point between resistors 57 and 62 .
If the control signal is not powered (step 1115 of FIG. 11 ), the superconductive device 42 may be operated such that it transfers to a resistive state, or the superconductive device 42 itself may be fabricated such that it does not exhibit a “gap” voltage (step 1125 of FIG. 11 ). This voltage will cause a current to flow through resistor 62 down to the output line 63 through control 65 and additional superconductive devices 66 . This current will be insufficient to switch additional superconductive devices 66 , and therefore, since control 65 is of very low inductance, the voltage across control 65 and additional superconductive devices 66 will be very small and will decay very rapidly, such that the current through resistor 62 will predominately go through control 65 and only a negligible amount will pass through resistor 67 , and eventually all current will pass through control 65 and additional superconductive devices 66 .
The current through control 65 depresses the maximum allowed zero resistance current of superconductive device 51 , which then triggers and produces a signal for transfer to the memory circuits (step 1130 of FIG. 11 ). In an alternative embodiment, other equivalent sensing circuits may be used instead. The pulse sensed by the memory circuit is inverted, amplified, and fed back via terminal 70 (step 1135 of FIG. 11 ) after an appropriate delay, with sufficient current to exceed the allowed maximum current through superconductive devices 66 and thereby impose a voltage on the output line 43 , which will cause current to flow through resistors 62 and 67 . However, only superconductive device 42 has a suppressed maximum current, and therefore only line 56 will experience a current back into control 71 via resistor 57 ; input line 72 will not. As before, control 71 will control superconductive device 75 and the current through superconductive devices 55 will be too small to switch superconductive devices 55 into the voltage state. The input pulse a will be returned as an ‘acknowledge’ pulse t only to the processor 61 , which generated pulse a (step 1140 of FIG. 11 ), and to no other, provided that the selected cell 41 is the only one energized. This return path is also valid for transfers of data from memory back to the processor 61 .
Superconductive Crossbar Switch with Summing Devices
With reference to FIG. 12 , there is shown a crossbar switch 39 having a number of summing devices 78 , represented in this embodiment by amplifiers M i , coupled to each output line 43 (e.g., O 3 , O 9 , O 10 ). The summing amplifier M 9 is coupled to output line 0 9 , and so on. The summing devices 78 are operable for summing the output voltages of the cells coupled to the respective output line O i . Summing the input voltages in this manner enables the crossbar switch to accommodate a plurality of inputs and thus renders the matrix extendable in numbers of inputs and outputs. This comes about because the input terminal of the amplifier is summed to zero voltage, thereby producing no crosstalk from the selected processor to the other processors.
Superconductive Crossbar Switch with Additional Junction and Control Line
In order to prevent interference by other processors after an output line has been acquired, an additional junction and control line is provided as is illustrated in FIG. 13 . The operation of this device will also be described below with reference to FIGS. 14 and 15 . In the crossbar's initial state, current is applied to clamp line C 8 , thereby depressing the maximum zero resistance current of superconductive device 46 a (step 1405 of FIG. 14 ). When terminal 45 a is activated, current will be caused to flow through inductor 106 and control line 107 , because the critical current of superconductive device 46 a has been reduced to below the imposed decoder current level. This will occur because the clamp current C suppresses the maximum zero resistance current of device 46 a.
With respect to cell 41 b , current at terminal 45 b will initially flow into inductor 108 because the inductance of inductor 108 is required to be lower than the inductance of inductor 106 (step 1410 of FIG. 14 ). However, since superconductive device 46 a has its maximum zero resistance current reduced because of the signal imposed at C 8 , superconductive device 46 a will switch to the voltage state, and all the current imposed on terminal 45 b will be directed through inductor 106 and control line 107 .
After the decoder has applied its current at terminal 45 b , a flag pulse or set of pulses is inserted into the processor datastream at I 4 (step 1415 of FIG. 14 ). These pulses would normally immediately follow those that select the address. When these flag pulses are detected on the output line O 8 for the cell, the CLAMP current on C 8 will be dropped (step 1420 of FIG. 14 ). Now, if decoder power to terminal 45 b is removed, the flux stored in inductor 106 will be maintained by a circulating current in the loop comprising inductors 106 , 108 and device 46 a . This action of dropping the clamp signal succeeds in not only retaining the usage of the output line in cell 41 a after the decoder is powered down, but it also prohibits interference by other requesters for the same output line (e.g., in cell 41 c ).
With reference to cell 45 c of FIG. 13 , the initial state has the CLAMP line C 8 energized, similar to as described above with regard to FIG. 7 . Removal of the CLAMP current at C 8 causes the critical current of device 46 a to no longer be depressed (step 1425 of FIG. 14 ). Decoder power applied to terminal 45 c , will then flow predominately through inductor 111 , which is required to have much smaller inductance than the inductance of inductor 112 .
The resulting current through inductor 112 , and thus control line 113 , will be insufficient to depress the critical current of device 116 enough for it to switch when data current flows through resistor 117 . This, in effect, prevents interference by the processor (step 1430 of FIG. 14 ) coupled to line I 5 , with the output line O 8 already in use. By extension, this operation will hold for all late requesters for an output line.
FIG. 15 summarizes the above described behavior. Processor 1 is shown having powered its decoder output, thereby permitting its flag bit to be sent to the SENSE circuits. At a later time, this causes the CLAMP to be dropped at time C from OPEN to CLAMPED at the cell location. Processor 2 thus is unable to insert its flag pulse onto the output line. Finally, the “acknowledge” return pulse is received by only processor 1 , as processor 2 connection is not enabled.
Contention Situation
If two processors request the same memory line at the “same time,” a contention situation occurs. For example, in FIG. 16 , if the address lines 45 b and 45 d are “simultaneously” powered, contention will occur between the processors coupled via inputs I 4 and I 5 for the memory coupled to output line O 9 . This will cause the memory acquisition to “flag” bits from both the processors coupled to I 4 and I 5 , and thus to drive the output line at the same time. This will produce two units of current in the control line 91 , which triggers the “contention” sensor 92 . Detection of this event will cause the support electronics to ignore the SENSE signal and to keep the CLAMP line on current HIGH. This function may also be provided by cryogenic circuitry. No return “acknowledge” pulse is sent, thereby, by its absence, informing the requesting sources of their failure to acquire the requested output line.
Situation Where Two Processors Have Requested Memory
FIG. 17 depicts the situation wherein processors 1 and 2 have requested the memory at the same time. In that event, the clamp line is not dropped at C, the crossbar cells on that memory line stay available, and no “acknowledge” pulse is returned to the requesters. This silence advises them to retry. If processor 2 requests the memory line at a time between a and C, the electronics can still keep CLAMP high, withhold “acknowledge,” and thereby maintain availability to other requesters. This may be done at cryogenic temperature or at room temperature.
Example of 128×128 Switch
FIG. 18 shows an example of a 128 input×128 output crossbar switch embodying the features of the present invention. In this example, 64 processors 126 - 126 are coupled to a processor glue chip 127 and 64 memories 128 - 128 are each coupled to a memory glue chip 131 . There are 64 more processors 136 - 136 coupled to a second processor glue chip 137 and an additional 64 memories 132 - 132 coupled to a second memory glue chip 133 . Connected between these glue chips is a crossbar switch 138 essentially comprising a plurality of interconnecting matrices of cells S 1 -S 16 , each of which is a 32×32 crossbar matrix. Each of the 64 processors 126 - 126 is coupled via an input data line 141 to processor glue chip 127 , to which each of the 64 processors 126 - 126 transmits serial bit data. Processor glue chip 127 outputs and receives that data into chips S 1 , S 2 , S 5 , S 6 for transactions to and from memories 128 - 128 by the 64 processors 126 - 126 . It also outputs and receives the data into chips S 9 , S 10 , S 13 , S 14 for transactions to and from memories 132 - 132 by the same 64 processors 126 - 126 . Likewise, chips S 3 , S 4 , S 7 , S 8 connect processors 136 - 136 to memories 128 - 128 while chips S 11 , S 12 , S 15 , S 16 connect processors 136 - 136 to memories 132 - 132 .
The selection of a memory line by a given processor is accomplished by including a destination memory address in that processor's submitted data word and clocking it via the appropriate input clock line on the proper crossbar chip (i.e., the required input processor and sought-for-output memory line). The destination address may also be introduced by an external controller and may also be decoded by an external decoder.
The return data from the interrogated memory line is fed into the corresponding memory glue chip as DRIVE, returned in parallel to the crossbar bank and is transferred to only the activated and locked processor line. From there, it continues to the corresponding processor glue chip and on to the originating processor. Clamping is accomplished by controlling a separate line (not shown), which disables access of all the unselected processors to the activated memory line. Contention is separately detected on the memory glue chip.
Switch Chip
FIG. 19 illustrates an embodiment of a switch chip that interconnects 32 input lines to 32 output lines via the previously described matrix of cells. In this example, each processor is assigned and coupled to its own decoder, which decodes the destination address that was requested by that processor and activates the address line of the proper cell in the matrix, as previously described. Such a chip may be replicated to populate the 128×128 matrix described in FIG. 17 .
Example embodiments of the present invention have been described in accordance with the above advantages. It will be appreciated that these examples are merely illustrative of the invention. Many variations and modifications will be apparent to those skilled in the art. | A superconductor crossbar switch for connecting a plurality of inputs with a plurality of outputs, including a switching cell having an input, an output and a circuit for connecting the input with the output for bidirectionally transmitting data therebetween. The connection of the retaining and releasing circuitry of a plurality of cells enables the switch to simultaneously retain a selected cell or cells of a group of cells and disable the remaining cells of that group, whereby a subsequent query on a disabled cell is inoperative until the selected cell or cells is released. The crossbar switch is characterized by latency on the order of nanoseconds, a data rate per channel on the order of gigabits per second, essentially zero crosstalk, and detection of contention in nanoseconds or less and resolution of contention in nanoseconds or less. | 7 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present application relates to a pressure-sensitive adhesive composition for an optical film, a polarizing plate and a liquid crystal display.
[0003] 2. Discussion of Related Art
[0004] A liquid crystal display (LCD) usually includes a liquid crystal panel containing a liquid crystal component injected between two transparent substrates and an optical film. As an optical film, there is a polarizing film, a retardation film or a brightness enhancing film. To laminate these optical films or attach an optical film to an adherent such as a liquid crystal panel, a pressure-sensitive adhesive for an optical film is generally used.
[0005] A pressure-sensitive adhesive may use an acrylic polymer, rubber, a urethane resin, a silicon resin or ethylene vinyl acetate (EVA) resin, and as a pressure-sensitive adhesive for an optical film, particularly, a polarizing plate, a pressure-sensitive adhesive including an acrylic polymer which has excellent transparency, and high resistance to oxidation or yellowing is generally used.
[0006] Such a pressure-sensitive adhesive is prepared by coating a pressure-sensitive coating solution including an acrylic polymer and a crosslinking agent, that is, a pressure-sensitive adhesive composition, and then curing the composition. Meanwhile, to ensure durability and cohesive strength required for the pressure-sensitive adhesive particularly used for a polarizing plate, an acrylic polymer having a weight average molecular weight of 1,500,000 to 2,000,000 is usually included in the pressure sensitive adhesive composition.
[0007] The density of such a pressure-sensitive adhesive composition including a polymer having a large weight average molecular weight increases as the coating solid content included therein is set higher. Accordingly, when a large amount of solvent is input to coat a pressure-sensitive adhesive solution, coating productivity and coating uniformity are significantly decreased.
[0008] However, when the weight average molecular weight of the polymer is decreased to solve the above-mentioned problem, durability and re-workability of the pressure-sensitive adhesive are drastically decreased.
[0009] A method of preparing a pressure-sensitive adhesive by repeating a coating process will be used to achieve the desired thickness, but the coating solid content is set low. However, the method has problems of decreased productivity with respect to production cost, and difficulty in precise control of the thickness of the pressure-sensitive adhesive.
[0010] Japanese Patent Laid-Open No. 2011-057794 (Reference 1) discloses an attempt to increase the coating solid content and satisfy durability by blending multifunctional isocyanate and a radical initiator with an acrylic polymer having an average molecular weight of 500,000 to 1,000,000. However, it is necessary to increase drying temperature or drying time after coating in order to prevent residue of the radical initiator from forming.
[0011] Japanese Patent Laid-Open No. 2004-091500 (Reference 2) discloses an attempt to add a carboxyl, amide or amino group to an acrylic polymer with a hydroxyl group, which has a weight average molecular weight of 500,000 to 2,000,000, and adjust gel content after being crosslinked at 1 to 50%. However, a pressure-sensitive adhesive prepared by an above-mentioned method is difficult to be used in practice due to considerably low re-workability and great change with the passage of time.
SUMMARY OF THE INVENTION
[0012] The present application provides a pressure-sensitive adhesive composition for an optical film, a polarizing plate and a liquid crystal display.
[0013] One aspect of the present application provides a pressure-sensitive adhesive composition for an optical film. The pressure-sensitive adhesive composition may include an acrylic polymer having a weight average molecular weight (M w ) of 700,000 to 1,200,000. The acrylic polymer may include at least one monomer having hydroxyl group and at least monomer having carboxyl group as polymerized units. The acrylic polymer may include 2.5 to 5.5 parts by weight of the monomer having hydroxyl group, and 0.05 to 0.3 parts by weight of the monomer having carboxyl group. In the specification, unless specifically defined otherwise, the unit part by weight refers to a ratio between components by weight.
[0014] The pressure-sensitive adhesive composition may include the coating solid content in an amount of 20 weight %. In the present application, the term “coating solid content” as used herein may refer to a solid content of a pressure-sensitive adhesive composition at the time that the pressure-sensitive adhesive composition is applied to a coating process in order to prepare a pressure-sensitive adhesive. The solid content may be measured in the manner suggested in the following Example. Conventionally, at the time that the pressure-sensitive adhesive composition is applied to the coating process, the composition may include an acrylic polymer, a crosslinking agent, an initiator, another additive, and also a solvent.
[0015] The pressure-sensitive adhesive composition may be a pressure-sensitive adhesive composition for an optical film. The pressure-sensitive adhesive composition for an optical film may be used to laminate an optical film such as a polarizing film, a retardation film, an anti-glare film, a wide viewing angle compensation film or a brightness enhancing film, or attach the optical film or a laminate to an adherent such as a liquid crystal panel. In one example, the pressure-sensitive adhesive composition may be used for a polarizing plate to attach a polarizing film to a liquid crystal panel.
[0016] The pressure-sensitive adhesive composition includes an acrylic polymer having a weight average molecular weight of 700,000 to 1,200,000. In the present application, the weight average molecular weight is a conversion value with respect to standard polystyrene measured by gel permeation chromatography (GPC), for example, in the manner described in the following Example. In the specification, unless specifically defined otherwise, the term “molecular weight” as used herein may refer to a “weight average molecular weight.” The acrylic polymer may have a molecular weight of 700,000 to 1,150,000; 700,000 to 1,100,000; 700,000 to 1,000,000; 700,000 to 950,000; or 700,000 to 900,000. When the molecular weight of the acrylic polymer is more than 1,200,000, and the pressure-sensitive adhesive composition has a high coating solid content, it is impossible to perform a coating process. Moreover, when the molecular weight is less than 700,000, durability and re-workability of the pressure-sensitive adhesive are significantly degraded.
[0017] The acrylic polymer may include a monomer having hydroxyl group and a monomer having carboxyl group as polymerized units. In the present application, the term “monomer having hydroxyl group” as used herein may refer to a monomer capable of being copolymerized with another monomer forming the acrylic polymer and providing a hydroxyl group to a side chain or terminal end of the polymer after copolymerization, and the term “monomer having carboxyl group” as used herein may refer to a monomer capable of being copolymerized with another monomer forming the acrylic polymer and providing a carboxyl group to a side chain or terminal end of the polymer after copolymerization.
[0018] The monomer having hydroxyl group may be included in an amount of 2.5 to 5.5 parts by weight, 3 to 5.5 parts by weight, or 3 to 5 parts by weight. When the monomer is included in an amount of 2.5 parts by weight or more, a suitable gel fraction may be maintained after being crosslinked, and durability and reliability and re-workability may be ensured. When the monomer is included in an amount of 5.5 parts by weight or less, suitable gel content may be maintained after being crosslinked and a physical property such as durability and reliability may be ensured. The monomer may be any one capable of being polymerized with another monomer forming an acrylic polymer, for example, a monomer having a carboxyl group or a (meth)acrylic acid ester monomer to be described later, and providing a hydroxyl group to a side chain or terminal end of the polymer after polymerization without limitation. An example of the monomer may be, but is not limited to, a hydroxyalkyl(meth)acrylate such as 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, 6-hydroxyhexyl(meth)acrylate or 8-hydroxyoctyl(meth)acrylate, or a hydroxyalkyleneglycol(meth)acrylate such as 2-hydroxyethyleneglycol(meth)acrylate or 2-hydroxypropyleneglycol(meth)acrylate. One or at least two of the above-mentioned monomers may be included in the polymer.
[0019] In addition, a monomer having a carboxyl group may be included in an acrylic polymer in an amount of 0.05 to 0.3 parts by weight, or 0.07 to 0.3 parts by weight. When the monomer is included in an amount of 0.05 parts by weight or more, suitable cure rate and gel fraction may be ensured, and excellent productivity, durability and reliability may be maintained. Moreover, when the monomer is included in an amount of 0.3 parts by weight or less, durability and reliability, and durability and reliability in long-term storage of a pressure-sensitive adhesive composition or pressure-sensitive polarizing plate may be ensured. In addition, the monomer may be any one capable of being copolymerized with another monomer forming an acrylic polymer and providing a carboxyl group to a side chain or terminal end of the polymer after copolymerization without limitation. An example of the monomer may be (meth)acrylic acid, 2-(meth)acryloyloxy acetate, 3-(meth)acryloyloxy propylate, 4-(meth)acryloyloxy butyrate, acrylic acid dimer, itaconic acid, maleic acid or maleic acid anhydride. One or a mixture of at least two of the above-mentioned monomers may be used.
[0020] The acrylic polymer may include a (meth)acrylic acid ester monomer as a polymerized unit.
[0021] The (meth)acrylic acid ester monomer may be alkyl(meth)acrylate. Here, alkyl(meth)acrylate which contains an alkyl group having 2 to 12 carbon atoms may be used in consideration of the control of cohesive strength, a glass transition temperature and an adhesive property. Examples of the monomer may include methyl(meth)acrylate, ethyl(meth)acrylate, n-propyl(meth)acrylate, isopropyl(meth)acrylate, n-butyl(meth)acrylate, t-butyl (meth)acrylate, sec-butyl(meth)acrylate, pentyl(meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-ethylbutyl(meth)acrylate, n-octyl(meth)acrylate, isobornyl(meth)acrylate, isooctyl(meth)acrylate, isononyl(meth)acrylate and lauryl(meth)acrylate. One or at least two of the above-mentioned monomers may be included in the polymer. For example, the (meth)acrylic acid ester monomer may be included in the acrylic polymer in an amount of 80 to 97.8 parts by weight.
[0022] The acrylic polymer may further include another comonomer as a polymerized unit when necessary. The comonomer which may be included additionally may be a nitrogen-containing monomer such as (meth)acrylonitrile, (meth)acrylamide, N-methyl(meth)acrylamide, N-butoxy methyl(meth)acrylamide, N-vinyl pyrrolidone or N-vinyl caprolactame; an alkylene oxide group-containing monomer such as alkoxy alkyleneglycol(meth)acrylic acid ester, alkoxy dialkyleneglycol(meth)acrylic acid ester, alkoxy trialkyleneglycol(meth)acrylic acid ester, alkoxy tetraalkyleneglycol(meth)acrylic acid ester, alkoxy polyethyleneglycol(meth)acrylic acid ester, phenoxy alkyleneglycol(meth)acrylic acid ester, phenoxy dialkyleneglycol(meth)acrylic acid ester, phenoxy trialkyleneglycol(meth)acrylic acid ester, phenoxy tetraalkyleneglycol(meth)acrylic acid ester or phenoxy polyalkyleneglycol(meth)acrylic acid ester; a styrene-based monomer such as styrene or methyl styrene; a glycidyl group-containing monomer such as glycidyl(meth)acrylate; or a carboxylic acid vinyl ester such as vinyl acetate. One or at least two selected from the above-mentioned comonomers may be included in the polymer when necessary. The comonomer may be included in an acrylic polymer in an amount of 20 parts by weight or less, or 0.1 to 15 parts by weight.
[0023] The acrylic polymer may be prepared by a conventional polymerization method. For example, the acrylic polymer may be prepared by subjecting a monomer mixture prepared by blending monomers selected according to the composition of a desired monomer, to a polymerization method such as solution polymerization, photo polymerization, bulk polymerization, suspension polymerization or emulsion polymerization. When necessary, in this step, a suitable polymerization initiator, a molecular weight regulator or a chain transfer agent may be used together.
[0024] The pressure-sensitive adhesive composition of the present application may further include a multifunctional crosslinking agent as a component capable of crosslinking the acrylic polymer in curing. The term “curing” as used herein may refer to a reaction allowing the pressure-sensitive adhesive composition to exhibit a pressure-sensitive adhesive property through a physical or chemical action, or reaction of components included in the pressure-sensitive adhesive composition. In the present application, in some cases, the terms “curing” and “crosslinking” may have the same meaning as each other. The multifunctional crosslinking agent may be an isocyanate crosslinking agent, an epoxy crosslinking agent, an aziridin crosslinking agent or a metal chelate crosslinking agent, and preferably an isocyanate crosslinking agent.
[0025] The isocyanate crosslinking agent may be a diisocyanate compound such as toluene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoboron diisocyanate, tetramethylxylene diisocyanate or naphthalene diisocyanate; or a compound produced by reacting the diisocyanate compound with a polyol. As such, the polyol may be trimethylol propane.
[0026] In the present application, one or at least two of the above-mentioned crosslinking agents may be used, but the present application is not limited thereto.
[0027] The multifunctional crosslinking agent may be included in the pressure-sensitive adhesive composition in an amount of 0.01 to 5 parts by weight relative to 100 parts by weight of the acrylic polymer, and the pressure-sensitive adhesive may maintain excellent gel fraction, cohesive strength and durability within the above range.
[0028] The pressure-sensitive adhesive composition may further include a silane coupling agent having a beta-cyano group or acetoacetyl group. The silane coupling agent may allow the pressure-sensitive adhesive formed using an acrylic polymer having a low molecular weight to exhibit excellent adhesion and adhesion stability, and maintain excellent durability and reliability under heat resistance and humidity and heat resistance conditions.
[0029] The silane coupling agent having a beta-cyano group or acetoacetyl group may be a compound represented by Formula 1 or 2.
[0000] (R 1 ) n Si(R 2 ) (4-n) [Formula 1]
[0000] (R 3 ) n Si(R 2 ) (4-n) [Formula 2]
[0030] In Formula 1 or 2, R 1 is a beta-cyanoacetyl group or beta-cyanoacetylalkyl group, R 3 is an acetoacetyl group or acetoacetylalkly group, R 2 is an alkoxyl group, and n is a number between 1 and 3.
[0031] In Formula 1 or 2, an alkyl group may be an alkyl group having 1 to 20, 1 to 16, 1 to 12, 1 to 8, or 1 to 4 carbon atoms. In this case, the alkyl group may be linear, branched or cyclic. In addition, in Formula 1 or 2, an alkoxy group may be an alkoxy group having 1 to 20, 1 to 16, 1 to 12, 1 to 8, or 1 to 4 carbon atoms. In this case, the alkoxy group may be linear, branched or cyclic.
[0032] Moreover, in Formula 1, n may be one of 1 to 3, 1 to 2 or 1.
[0033] The compound of Formula 1 or 2 may be, but is not limited to, acetoacetylpropyl trimethoxy silane, acetoacetylpropyl triethoxy silane, O-cyanoacetylpropyl trimethoxy silane or β-cyanoacetylpropyl triethoxy silane.
[0034] The pressure-sensitive adhesive composition may include 0.01 to 5 parts by weight, or 0.01 to 1 part by weight of the silane coupling agent relative to 100 parts by weight of the acrylic polymer, and when the silane coupling agent is included within the range, it may effectively provide desired physical properties to the pressure-sensitive adhesive.
[0035] The pressure-sensitive adhesive composition may further include a pressure-sensitive adhesion providing agent when necessary. The pressure-sensitive adhesion providing agent may include one or a mixture of at least two of a hydrocarbon resin or hydrogenated product thereof, a rosin resin or hydrogenated product thereof, a rosin ester resin or hydrogenated product thereof, a terpene resin or hydrogenated product thereof, a terpene phenol resin or hydrogenated product thereof, a polymerized rosin resin and polymerized rosin ester resin, but the present application is not limited thereto. The pressure-sensitive adhesion providing agent may be included in the pressure-sensitive adhesive composition in an amount of 100 parts by weight or less relative to 100 parts by weight of the acrylic polymer.
[0036] The pressure-sensitive adhesive composition may further include at least one additive selected from the group consisting of an epoxy resin, a curing agent, a UV stabilizer, an oxidation preventing agent, a coloring agent, a reinforcing agent, a filler, a foaming agent, a surfactant and a plasticizer within the range that does not affect an effect of the present application.
[0037] The coating solid content of the pressure-sensitive adhesive composition may be 20 weight % or more, or 25 weight % or more. When the coating solid content is 20 weight % or more, the productivity of the pressure-sensitive adhesive, optical film or liquid crystal display may be maximized. The upper limit of the coating solid content is not specifically limited, and may be suitably controlled within the range of 50 weight % or less, 40 weight % or less, or 30 weight % or less in consideration of viscosity to be applied to coating.
[0038] The pressure-sensitive adhesive composition may have a viscosity (at 23° C.) of 500 to 2,500 cP, 700 to 2,500 cP, or 900 to 2,300 cP in the state that the coating solid content is maintained. That is, the pressure-sensitive adhesive composition may have a viscosity at a level capable of effective coating in the state that the coating solid content is set high.
[0039] The pressure-sensitive adhesive composition may have a gel fraction of 55 to 85 weight %, or 60 to 80 weight % after curing or crosslinking. The gel fraction may be calculated by Equation 1.
[0000] Gel Fraction (%)= B/A× 100 [Equation 1]
[0040] In Equation 1, A is the weight of the pressure-sensitive adhesive composition after being curing or crosslinking, and B is the dry weight of non-dissolved parts taken after immersing the cured or crosslinked pressure-sensitive adhesive composition in ethyl acetate at room temperature for 72 hours.
[0041] When the gel fraction is 55 weight % or more, excellent durability and reliability and re-workability may be maintained, and when the gel fraction is 85 weight % or less, excellent durability and reliability may be maintained.
[0042] Another aspect of the present application provides a method of preparing a pressure-sensitive adhesive for an optical film. The method may include coating the pressure-sensitive adhesive composition described above and performing curing or crosslinking.
[0043] The present application may maintain excellent productivity and thickness precision, and also maintain excellent physical properties such as re-workability and durability and reliability of the pressure-sensitive adhesive by using the coating solid content of the pressure-sensitive adhesive composition.
[0044] A method of coating a pressure-sensitive adhesive composition is not specifically limited, and may be performed by applying a pressure-sensitive adhesive composition to a suitable process base material, for example, a releasable film or an optical film using a conventional means such as a bar coater.
[0045] For uniform coating, a multifunctional crosslinking agent included in the pressure-sensitive adhesive composition may be controlled not to perform crosslinking of functional groups during the coating process. Accordingly, a crosslinked structure may be formed in a curing and aging process after the coating of the crosslinking agent, and thereby cohesive strength of the pressure-sensitive adhesive may be improved, and pressure-sensitive adhesive properties and cuttability may be improved.
[0046] The coating may be performed after a volatile component or a bubble-forming component such as reaction residue in the pressure-sensitive adhesive composition is sufficiently removed. Accordingly, it may prevent problems such that elasticity of the pressure-sensitive adhesive is decreased due to excessively low crosslinking density or molecular weight, and bubbles present between a glass plate and a pressure-sensitive adhesive layer become larger at a high temperature, thereby forming a scatterer therein.
[0047] In the preparation method, a method of curing the pressure-sensitive adhesive composition is not specifically limited, and thus, for example, the coating layer may be maintained at a suitable temperature to induce crosslinking between the acrylic polymer contained in the coating layer and the multifunctional crosslinking agent.
[0048] Still another aspect of the present application provides a polarizing plate including a polarizing film and a pressure-sensitive adhesive layer which contains the pressure-sensitive adhesive composition of the present application, is formed on one or both surfaces of the polarizing film and is used to attach the polarizing plate to a liquid crystal panel.
[0049] The pressure-sensitive adhesive composition may be included in the pressure-sensitive adhesive layer after curing or crosslinking is performed.
[0050] The kind of polarizing film used in the present application is not specifically limited, and thus a general one known in the art may be employed.
[0051] The kind of polarizing film included in the polarizing plate of the present application is not specifically limited, and thus a general one known in the art, for example, a polyvinylalcohol-based polarizing film, may be employed without limitation.
[0052] The polarizing film is a functional film capable of extracting only light vibrating in one direction from incident light vibrating in various directions. In the polarizing film, a dichroic dye may be adsorbed and arranged to a polyvinylalcohol-based resin film. The polyvinylalcohol-based resin comprising the polarizing film may be obtained by gelating a polyvinylacetate-based resin. In this case, the polyvinylacetate-based resin to be used may also include vinyl acetate and a copolymer of a monomer capable of being copolymerized with the vinyl acetate as well as a mono polymer of the vinyl acetate. The monomer capable of being copolymerized with the vinyl acetate may be, but is not limited to, one or a mixture of at least two of unsaturated carbonates, olefins, vinylethers, unsaturated sulfonates and acrylamides having an ammonium group. Generally, the degree of gelation of the polyvinylalcohol-based resin may be approximately 85 to 100 mol %, and preferably 98 mol % or more. The polyvinylalcohol-based resin may be further modified, and for example, may be polyvinylformal or polyvinylacetal modified with an aldehyde. Generally, the degree of polymerization of the poylvinylalcohol-based resin may be approximately 1,000 to 10,000, or 1,500 to 5,000.
[0053] The polarizing film may be manufactured through orienting a polyvinylalcohol-based resin film (e.g., uniaxial orientation), dying the polyvinylalcohol-based resin film with a dichroic dye, adsorbing the dichroic dye, treating the polyvinylalcohol-based resin film to which a dichroic dye is adsorbed with a boric acid aqueous solution, and then washing the polyvinylalcohol resin film. Here, as the dichroic dye, iodine or a dichroic organic pigment may be used.
[0054] The polarizing plate of the present application may further include a protecting film attached to one or both surfaces of the polarizing film, and in this case, the pressure-sensitive adhesive layer may be formed to one surface of the protecting film. The kind the protecting film is not specifically limited, and thus may be a cellulose-based film such as formed of triacetyl cellulose (TAC); a polyester-based film such as a polycarbonate or poly(ethylene terephthalate) (PET) film; a polyethersulfone-based film; and a film having one or a stacked structure having at least two of a polyethylene film, a polypropylene film and a polyolefin-based film manufactured using a resin having a cyclo-based or norbornene structure or an ethylene-propylene copolymer.
[0055] The polarizing plate may further include at least one functionalized layer selected from the group consisting of a protecting layer, a reflective layer, an anti-glare layer, a retardation plate, a wide viewing angle compensating film and a brightness enhancing film.
[0056] In the present application, a method of forming a pressure-sensitive adhesive layer on the polarizing plate is not specifically limited, but a method of preparing a pressure-sensitive adhesive may be, for example, applied. In this case, a method of directly coating and curing a pressure-sensitive adhesive composition to the polarizing plate, or a method of coating and curing a pressure-sensitive adhesive composition to a release-treated surface of a releasable film and transferring the resulting composition to the polarizing plate may be used.
[0057] Yet another aspect of the present application provides a liquid crystal display including a liquid crystal panel and the polarizing plate attached to one or both surfaces of the liquid crystal panel.
[0058] As a liquid crystal panel in the device, a known panel such as a passive matrix-type panel such as a twisted nematic (TN), super twisted nematic (STN), ferroelectric (F) or polymer dispersed (PD) panel, an active matrix-type panel such as a two or three terminal panel, an in-plane switching (IPS) panel or a vertical alignment (VA) panel may be used.
[0059] Another kind of component of the liquid crystal display, for example, a color filter substrate or an upper and lower substrate such as an array substrate, is not specifically limited, and a conformation known in the art may be employed without limitation.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0060] Hereinafter, a pressure-sensitive adhesive composition will be described in detail through Example and Comparative Example, but a range of the pressure-sensitive adhesive composition is not limited by the following Example.
[0061] In the following Examples and Comparative Examples, respective physical properties were evaluated by the following methods:
[0062] 1. Weight Average Molecular Weight of Polymer
[0063] A weight average molecular weight and molecular weight distribution of acrylic polymers were measured using GPC according to the following condition. To plot a calibration curve, standard polystyrene produced by Agilent System was used, and the measurement result was converted.
[0064] <Condition for Measuring Weight Average Molecular Weight>
[0065] Measurer: Gel Permeation Chromatography (Waters Alliance System)
[0066] Column: PL Mixed B type
[0067] Detector: Refractive Index Detector
[0068] Column Flow Rate and Solvent: 1 mL/min, tetrahydrofuran (THF)
[0069] Analysis Temperature and Measuring Amount: 40° C., 200 μl
[0070] 2. Evaluation of the Coating Solid Content
[0071] The coating solid content was measured by the following method:
[0072] <Order of Measuring the Coating Solid Content>
[0073] 1) Weight (A) of an aluminum dish was measured.
[0074] 2) Approximately 0.3 to 0.5 g of a pressure-sensitive adhesive composition (sample before being dried) prepared in Example or Comparative Example was taken and put in the aluminum dish whose weight was measured in advance.
[0075] 3) A small amount of a polymerization inhibitor solution (hydroquinone) (concentration: 0.5 weight %) dissolved in ethyl acetate was added to the pressure-sensitive adhesive using a pipette.
[0076] 4) The resulting solution was dried in a 150° C. oven for approximately 30 minutes so as to remove solvent.
[0077] 5) The solution was cooled at room temperature for approximately 15 to 30 minutes, and the weight of the remaining component (weight of the sample after being dried) was measured.
[0078] 6) The coating solid content was measured according to the following Equation:
[0000] Coating TSC (solid content, unit:%)=( DS−A )/( S+E )×100
[0079] DS: Weight of Aluminum Dish+Weight of Sample After being Dried (unit: g)
[0080] A: Weight of Aluminum Dish (unit: g)
[0081] S: Weight of Sample before being Dried (unit: g)
[0082] E: Weight of Removed Component (ex. Solvent) (unit: g)
[0083] 3. Evaluation of Coatability
[0084] Coatability exhibited during coating process of a pressure-sensitive adhesive composition prepared in Example or Comparative Example was evaluated by observing the state of a coating layer with the naked eyes according to the following criteria:
[0085] <Criteria for Evaluating Coatability>
[0086] O: Neither bubbles nor stripes on a coating layer were observed with the naked eyes.
[0087] Δ: Fine bubbles and/or stripes on a coating layer were observed with the naked eyes.
[0088] X: Bubbles and/or stripes on a coating layer were clearly observed with the naked eyes.
[0089] 4. Measurement of Gel Fraction
[0090] A pressure-sensitive adhesive layer prepared in Example or Comparative Example was maintained in a constant temperature and humidity chamber (23° C., relative humidity: 60%) for 10 days. Then 0.3 g of the pressure-sensitive adhesive layer was taken and put in a #200 stainless wire mesh. The mesh was then put into 100 mL of ethyl acetate so as for the pressure-sensitive adhesive layer to be completely submerged in the ethyl acetate, and then maintained in a dark room at room temperature for 3 days. Then, portions (non-dissolved parts) of the pressure-sensitive adhesive layer, which were not dissolved in the ethyl acetate, was taken, and then dried at 70° C. for 4 hours so as to measure the weight (dry weight of the non-dissolved parts) of the non-dissolved parts.
[0091] Then the gel fraction (unit: %) was measured by substituting the measured results to the following Equation:
[0092] [Equation for Measuring Gel Fraction]
[0000] Gel Fraction= B/A× 100
[0093] A: Weight of the Pressure-Sensitive Adhesive (0.3 g)
[0094] B: Dry Weight of the Non-dissolved Parts (unit: g)
[0095] 5. Evaluation of Re-Workability
[0096] A specimen was manufactured by cutting a pressure-sensitive polarizing plate formed in Example or Comparative Example so as to have a width of 90 nm and a length of 170 mm. Subsequently, a releasable PET film attached to a pressure-sensitive adhesive layer was peeled, and then the pressure-sensitive adhesive polarizing plate was attached to a non-alkali glass (Corning) using a 2 kg roller according to the JIS Z 0237. The non-alkali glass to which the polarizing plate was attached was left in a constant temperature and humidity chamber (23° C., relative humidity: 60%) for approximately 1 hour, heated at 50° C. for 4 hours, and then left at room temperature for 1 hour. Afterward, the polarizing plate was peeled from the non-alkali glass at a peel rate of 300 mm/min and a peel angle of 180 degrees using a texture analyzer (Stable Micro Systems, UK) to evaluate re-workability according to the following criteria:
[0097] <Criteria for Evaluating Re-Workability>
[0098] O: when the polarizing plate was easily peeled and thus no transfer residue remained
[0099] Δ: when peeling was not easy, or some transfer residue of the pressure-sensitive adhesive remained on the glass after peeling
[0100] X: when peeling was very difficult, enough to destroy the polarizing plate or glass, or a large amount of a transfer residue of the pressure-sensitive adhesive remained on the glass
[0101] 6. Durability and Reliability and Durability and Reliability after Long-Term Storage
[0102] A specimen was manufactured by cutting a polarizing plate formed in Example or Comparative Example so as to have a width of 90 mm and a length of 170 mm, and two sheets of the specimen manufactured as described above were attached to both surfaces of a glass having a width of 110 mm, a length of 190 mm and a thickness of 0.7 mm so as for light-absorption axes of the polarizing plate to be crossed with each other, thereby preparing a sample. A pressure applied in the attachment was approximately 5 kg/cm 2 , and the process was performed in a clean room to prevent entering of impurities or bubbles.
[0103] The humidity and heat resistance properties were evaluated by observing whether bubbles were generated or peeling occurred after the sample was left under conditions of a temperature of 60° C. and relative humidity of 90% for 1,000 hours.
[0104] In addition, heat resistance was evaluated by observing whether bubbles were generated or peeling occurred after the sample was left at 80° C. for 1,000 hours.
[0105] Evaluation of the humidity and heat resistance or heat resistance properties was performed after the specimen obtained after being left under the humidity and heat resistance or heat resistance condition was maintained at room temperature for 24 hours.
[0106] In addition, the durability and reliability after long-term storage was evaluated by examining the humidity and heat resistance and heat resistance properties in the same manner as described above after the sample was maintained for 5 months or more under conventional storage conditions.
[0107] Criteria for evaluating the durability and reliability were as follows:
[0108] <Criteria for Evaluating Durability>
[0109] ∘: No bubbles were generated and no peeling occurred.
[0110] Δ: Some bubbles were generated and/or peeling somewhat occurred.
[0111] x: A large amount of bubbles were generated and/or peeling considerably occurred.
Preparation Example 1
[0112] 96 parts by weight of n-butyl acrylate (n-BA), 3.9 parts by weight of hydroxybutyl acrylate, and 0.1 parts by weight of acrylic acid were poured into a 1 L reactor in which a nitrogen gas is refluxed and which has a cooling apparatus to facilitate temperature control, and a suitable amount of n-dodecyl mercaptane (n-DDM) was added. After 150 parts by weight of ethyl acetate was poured as a solvent, the reactor was purged with nitrogen gas for 60 minutes to remove oxygen. Afterward, the temperature was maintained at 66° C., 0.03 parts by weight of azobisisobutyronitrile (AIBN) was added as a reaction initiator, and the reaction product was diluted with ethyl acetate after a 16 hours reaction, thereby preparing an acrylic polymer solution (Al) having a weight average molecular weight of 950,000 and a solid content of 25.7 weight %.
Preparation Examples 2 to 10
[0113] Acrylic polymer solutions (A2 to A9) were prepared in the same manner as described in Example 1, except that components were controlled as shown in the following Table 1:
[0000]
TABLE 1
Preparation Example
1
2
3
4
5
6
7
8
9
10
Acrylic polymer
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
Solution
Composition
n-BA
96
96
96
98
93
96
96
96
99
96
of Monomer
HBA
3.9
3.9
3.7
2
6.7
3.9
3.9
3.9
1
3.9
AA
0.1
0.1
0.3
0.3
0.3
0.03
0.5
0.1
—
0.1
AIBN
0.03
0.03
0.03
0.03
0.03
0.03
0.03
0.03
0.03
0.03
nDDM
0.05
0.1
0.05
0.05
0.05
0.05
0.05
0.2
—
—
EAc
120
120
120
120
120
120
120
120
120
120
Mw (unit: ×10,000)
95
75
93
94
94
93
94
60
150
110
Content unit: part by weight
n-BA: n-butyl acrylate
HBA: hydroxybutyl acrylate
AA: acrylic acid
AIBN: azobisisobutyronitril
nDDN: n-dodecyl mercaptane
EAc: ethyl acetate
Mw: weight average molecular weight
Example 1
[0114] Preparation of Pressure-Sensitive Adhesive Composition (Coating Solution)
[0115] A coating solution (pressure-sensitive adhesive composition) was prepared by blending 0.1 parts by weight of a multifunctional crosslinking agent (a tolylenediisocyanate addition product of trimethylol propane, TDI-1) and 0.1 parts by weight of beta-cyanoacetylpropyl trimethoxy silane (LG Chemical Ltd., M-812) relative to 100 parts by weight of a solid content of the acrylic polymer solution (Al) of Preparation Example 1, and diluting the resulting product to have the coating solid content in an amount of approximately 22 weight %.
[0116] Preparation of Pressure-Sensitive Polarizing Plate
[0117] A pressure-sensitive adhesive layer was formed by coating the prepared coating solution on a release-treated surface of a poly(ethyleneterephthalate) (PET; MRF-38, Mitsubishi) film to have a thickness of 30 μm after drying, and drying the coated film under a suitable condition to have a gel fraction of approximately 70%. A pressure-sensitive polarizing plate was prepared by laminating the formed pressure-sensitive adhesive layer on one surface of an iodine-based polarizing plate having a thickness of 185 μm.
Examples 2 and 3 and Comparative Examples 1 to 7
[0118] A polarizing plate was prepared in the same manner as described in Example 1, except that the composition of a pressure-sensitive adhesive composition, the gel fraction of a pressure-sensitive adhesive and the coating solid content were as shown in the following Table 2. Though Comparative Example 7 uses a pressure-sensitive adhesive composition containing an acrylic polymer having a high molecular weight to have a coating solid content of 20%, it was impossible to perform coating and form a pressure-sensitive adhesive layer. Thus, a gel fraction could not be measured.
[0000]
TABLE 2
Example
Comparative Example
1
2
3
4
1
2
3
4
5
6
7
Kind of Polymer Solution
A1
A2
A3
A10
A1
A4
A5
A6
A7
A8
A9
Solid Content in Polymer
100
100
100
100
100
100
100
100
100
100
100
Solution
Content of Crosslinking
0.1
0.1
0.1
0.1
0.05
0.1
0.1
0.1
0.07
0.2
0.1
Agent
Content of Coupling
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
0.1
Agent
Gel Fraction (unit: %)
70
66
75
70
35
20
90
45
75
65
—
Coating solid content
22
25
22
20
23
22
22
22
22
27
20
(unit: %)
Content unit: part by weight
Crosslinking agent: tolylene diisocyante addition product of trimethylolpropane (TDI-1)
Coupling agent: beta-cyanoacetylpropyl trimethoxy silane (LG Chemical Ltd., M-812)
[0119] Evaluation results for physical properties with respect to Examples and Comparative Examples were summarized in Table 3.
[0000]
TABLE 3
Example
Comparative Example
1
2
3
4
1
2
3
4
5
6
7
Coatability
◯
◯
◯
◯
◯
◯
◯
◯
◯
◯
X
Re-workability
◯
◯
◯
◯
X
X
◯
X
◯
X
—
Durability &
Heat
◯
◯
◯
◯
◯
◯
◯
◯
◯
Δ
—
Reliability
resistance
Humidity
◯
◯
◯
◯
Δ
◯
Δ
◯
Δ
Δ
—
and heat
resistance
Durability &
Heat
◯
◯
◯
◯
Δ
Δ
◯
Δ
◯
X
—
Reliability
resistance
After
Humidity
◯
◯
◯
◯
X
X
X
X
X
X
—
Long-
and heat
term
resistance
Storage
[0120] As seen from the results in Table 3, Examples 1 to 4 showed excellent re-workability, durability and reliability and coatability, and also showed excellent durability and reliability even after long-term storage.
[0121] Meanwhile, in Comparative Examples 1 to 4, coating was possible due to a large solid content (coating solid content), but the re-workability and the durability and reliability were degraded. In addition, in Comparative Example 5, it was impossible to ensure the durability and reliability during long-term storage, and Comparative Example 6 was degraded in re-workability and durability and reliability. In addition, in Comparative Example 7, it was impossible to evaluate the physical properties since it was impossible to perform coating and form a pressure-sensitive adhesive layer from the beginning when the coating solid content was set to 20%.
[0122] A pressure-sensitive adhesive composition of the present application can be effectively coated even when the coating solid content of the composition is high. Thus, the pressure-sensitive adhesive composition can have considerably increased productivity in formation of a pressure-sensitive adhesive or manufacture of an optical film such as a polarizing plate, and excellent durability and reliability and re-workability even after being formed into a pressure-sensitive adhesive. | A pressure-sensitive adhesive composition for an optical film, a method of preparing a pressure-sensitive adhesive for an optical film, a polarizing plate and a liquid crystal display are provided. The pressure-sensitive adhesive composition may be effectively coated even when a coating solid content is controlled to be high. Therefore, productivity in formation of a pressure-sensitive adhesive or manufacture of an optical film such as a polarizing plate may be significantly increased, and excellent durability and reliability and re-workability may be exhibited after the pressure-sensitive adhesive is prepared. | 2 |
FIELD OF THE INVENTION
The present invention relates to high performance integrated circuits suitable for use in applications where reliability is important. More particularly, the present invention addresses circuit applications where reliability is enhanced by use of redundancy. The invention relates to a GaAs based circuit design approach which provides redundancy in order to obtain graceful degradation of circuit performance upon failure of individual components within the circuit, as well as increased yield of functional parts. According to the invention, redundancy is provided by designing the switch to include both series connected FET shunt and series connected series arms in the switch. A single pole double throw switch made according to the invention is capable of providing 1.3 dB insertion loss, return loss and isolation better than 20 dB and 35 dB, respectively over dc to 12 GHz, even if 25% of the FETs fail in each arm of the switch.
BACKGROUND AND SUMMARY OF THE INVENTION
In certain types of circuit applications it has become commonplace to provide for circuit redundancy. Typical of such applications are those where the national defense depends on the reliability of the circuit and those where human lives are dependent on proper circuit performance. For instance, many defense EW and ESM systems are designed to provide circuit redundancy. Additionally, such systems require the use of inherently reliable technologies, such as integrated circuitry rather than discrete components, to the maximum extent feasible. In airborne, spaceborne or remotely placed systems, an effective approach for circuit functions is required that provide the desired reliable performance with graceful degradation, in case of device failure, with cost as a major consideration. Monolithic technology provides inherent reliability relative to discrete components, is generally lower in cost due to the reduction in wire bonding and part count and also provides enhanced reproducibility since there are fewer opportunities to introduce variations into the end product.
Circuit applications requiring switching where redundancy is desired have not been satisfactorily implemented in GaAs technologies due to the absence of a feasible manner of implementing such circuits in GaAs integrated circuits. In the past, fast electronic switches using pin diodes have been designed and have been made redundant by using parallel or series diode pairs to replace single diodes. However, these switches require many discrete components, have high assembly costs, require exotic drivers, consume significant dc power, and allow the switching waveform to couple onto the rf signal path.
According to the present invention, redundancy is provided in a GaAs-based switch which is not dependent on the provision of pin diodes. N-way redundancy can be provided by employing GaAs MESFETs in a novel circuit design approach which is compatible with GaAs integrated circuit manufacturing technology. According to the novel design approach, GaAs MESFETs are arranged in series and shunt configurations in each series and shunt arm such that, if some of the MESFETs fail, the circuit still performs its intended function with very little degradation in the signal quality. A single pole single throw switch is shown in FIG. 2 which includes series connected MESFET shunt switching elements 121, 131 and series connected MESFET switching elements 111 to implement the redundancy feature. FIGS. 3 and 4 respectively illustrate single pole double throw and single pole triple throw switches including both series and shunt connected MESFETs. FIG. 5 illustrates the physical layout of the single pole double throw switch illustrated in FIG. 3.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and C illustrate a RLC model equivalent circuit for a FET of the type employed in the description of the invention.
FIG. 1B illustrates a block diagram of an implementation of the invention.
FIG. 2 illustrates a circuit schematic for a single pole single throw switch designed in accordance with the invention.
FIG. 3 illustrates a circuit schematic for a single pole double throw switch designed in accordance with the invention.
FIG. 4 illustrates a circuit schematic for a single pole triple throw switch designed in accordance with the invention.
FIG. 5 illustrates the physical layout of a single pole double throw switch for manufacture in a GaAs based technology.
FIG. 6 is a plot showing the calculated performance of a single pole single throw switch designed in accordance with the invention.
FIG. 7 is a plot showing the calculated performance of a single pole double throw switch designed in accordance with the invention.
FIG. 8 is a plot showing the calculated performance of a single pole triple throw switch designed in accordance with the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Redundancy to achieve high reliability and graceful degradation is often employed in military systems. In many redundant systems, parallel paths of components are provided which can be switched in case of failure in one of the signal paths. However, a failure in the switch will still destroy the system. Therefore, a redundant switch is required to enhance the system's reliability. The present invention provides a novel approach to realize an N-way redundant MESFET switch which can be fabricated with monolithic microwave integrated circuit (MMIC) technology. This switch design is redundant in the sense that it withstands the failure of one or more FETs while maintaining acceptable performance, greatly enhancing the expected reliability and yield of the switch.
The FET is a three terminal device and makes an excellent switch between the drain and the source. The conductivity between source and drain is controlled by a voltage at the gate. The gate control voltage can be applied through large resistor, having resistance of, for instance, 1 to 5 K-Ohm for providing isolation between the gate terminal and its bias supply. The dc power consumption is negligible because the FET behaves as a passive element, i.e. no bias is applied to the drain or source so that the total dc power consumption results from the gate leakage current. Each switching FET is modeled with an equivalent circuit in either the ON (low resistance) or OFF (high resistance) states. FIGS. 1A and 1C show an equivalent RLC models for the FET. For various gate peripheries, RLC values are given in Table 1.
TABLE 1______________________________________Equivalent Circuit values for switching FETshaving 0.8-μm gate lengthFET Size R R.sub.b L C C.sub.1(μm) (Ω) (Ω) (nH) (pF) (pF)______________________________________150 31 20k 0.03 0.04 0.03300 16 10k 0.06 0.07 0.05600 9 5k 0.1 0.13 0.09______________________________________
According to the invention, the switch circuit is designed to use series and series connected shunt combinations of switching FETs configured so that the circuit works with acceptable, although somewhat degraded performance, if some of the MESFETs fail. The FET gate peripheries are varied between 150 micrometers and 600 micrometers to obtain the best isolation, return loss, and the lowest insertion loss.
FIGS. 2-4 show schematics for single pole single throw (SPST), single pole double throw (SPDT), and single pole triple throw (SPTT) switches, respectively. Theoretically, switches larger than triple throw can be designed, however, the switch size of the MMIC must be limited for good yield. In view of the tradeoff between circuit size and production yield, the present description will be limited to descriptions of SPTT or smaller products.
TABLE 2______________________________________SUMMARY OF PERFORMANCE FORSPST, SPDT, AND SPTT REDUNDANT MMIC SWITCHESPerformance SPST SPDT SPTTFrequency (GHz) dc-12 dc-12 dc-12______________________________________Max. Ins. Loss (dB) 1.0 (1.2) 1.2 (1.3) 1.6 (1.7)Min. Isolation (dB) 35 (30) 40 (40) 40 (40)Min. Ret. Loss (dB) 18 (21) 22 (24) 13 (13)______________________________________
Table 2 summarizes the calculated performance as graphically illustrated in FIGS. 6-8 of the SPST, SPDT, and SPTT switches. This table shows that the switch performance promises to meet or exceed the performance of a nonredundant switch configured in the same manner. The insertion loss increases with the order of the switch but remains less than 2 dB in all cases. The isolation for all three switch configurations exceeds 35 dB and the return loss for the SPST and SPDT is greater than 18 dB while the SPTT has a worse case return loss of 13 dB. The values in parentheses on this table demonstrate the increased reliability. These values correspond to the worst case performance when 25% of the FETs in each arm are shorted at random. The performance degrades only slightly as the insertion loss remains below 2 dB and the return loss maintains its initial value or improves. Additionally, the SPDT and SPTT switches maintain their initial isolation value while the isolation of the SPST switch only degrades by 5 dB. The reliability analysis of a redundant switch was also carried out. The analysis predicted that the MTBF of the redundant switch (SPST) is on the order of 100 times the MTBF of a simple 2 FET switch.
The operation of the N-way redundant switch can be explained by reference to FIG. 1B where the switch 100 receives an input signal at input terminal 101. Matching network M1 (matching networks are labeled MN in FIG. 1B) provides impedance matching and passes the input signal to the first section 111 of the switch. Section 111 may be ON in which case the input signal is provided via matching network M2, to N2 which is coupled, via optional matching circuit M3 to output terminal 105. If section 111 is OFF, the input signal is blocked by section 111 and is not passed to output 105. A switch control signal is provided to section 111 from control circuit 131. The control signal on line 132 causes switch section 111 to operate in either the ON (conductive) state or the OFF (non-conductive) state.
A second switch section 121 is connected between node N2 and node N3, which is at ground. Matching circuit M4 is provided for impedance matching. A second control signal is provided to section 121 from control circuit 131 via line 134. Section 121 is operated in either the ON or OFF state to selectively ground the output 105. In operation of the switch 100, one section (111 or 121) is ON while the other is OFF. This causes the output 105 to be selectively coupled to either the input 101, when 111 is ON while 121 is OFF, or to the grounded node N3, when 111 is OFF while 121 is ON. Control circuit 131 can operate to provide the first and second control signals with opposite polarity to ensure the appropriate inverse operation of the first and second section 111, 121 of switch 100.
Control circuit 131 may be of any convenient design capable of providing control signals where the signal to one section is at an ON bias and the signal to the other section is an OFF bias.
Referring to FIG. 2, input 101 at node N1 is coupled via optional impedance matching circuit Ml to first section 111 of switch 100. Section 111 includes a first branch 112 having FETs Fl and F2 connected in series, source to drain, between node N1 and node N2. A second branch 114 includes FETs F3 and F4 connected in series, source to drain, between nodes Nl and N2, the second branch 114 being parallel with the first branch 112. The gates of FETs Fl, F2, F3 and F4 are all connected together and coupled, via line 113, to a control node NC for receipt via line 132 of the first control signal generated by control circuit 131 shown in FIG. 1B.
Redundancy is provided in this section 11 such that if any one of FETs Fl, F2, F3 or F4 becomes inoperative, only the branch 112 or 114 in which the inoperative FET resides will be disabled from ideal operation. For instance, if FET Fl fails such that it is always conductive, FET F2 will still be operative to turn branch 112 OFF and ON pursuant to the control signal on line 113. Should Fl fail such that it is always non-conductive, section 111 will operate correctly due to branch 114. In this situation, branch 112 is effectively removed from the circuit. Thus, by having FETs in series in each branch and having branches in parallel in each section, failure of any individual FET is not destructive insofar as operability of the section is concerned. Moreover, FET failures of less than all FETs in each branch will allow each such branch to remain operative if the mode of failure causes an undesired ON condition in the failed or defective FETs. Alternatively, if the failure mode of the FETs causes an undesired OFF condition, the section will continue to operate until there has been a failure in every branch.
The second section 121 of switch 100 includes two parallel branches the first made up of FETs F5, F6 and F7 connected in series to couple nodes N2 and N3, with optional matching circuits M3 and M5 shown in FIG. 2 between FET F5 and node N2. The second branch includes FETs F8, F9 and F10 coupled in series between nodes N2 and N3. As with section 111, the FETs of section 121 have their gates connected together, in this section at node ND. Line 123 provides the intergate connection to node ND.
The third section 131 includes first and second parallel branches made up of FETs F11, F12, F13 and F14, F15, F16, respectively. The branches, as in section 121, couple node N2 to ground, in this case at node N4. The gates are connected, via line 133 to node NE. The provision of a third section 131 in parallel with the second section 121, provides additional redundancy to the overall switch 100. Additionally, the provision of three FETs in each branch provides greater immunity from failure due to shorted FETs than does the arrangement in section 111 since three FETs in a row would become shorted less frequently than would be probable if only two FETs were provided in series as exemplified in section 111.
The optional impedance matching circuitry M1, M2, M3, M5 is available to optimize circuit performance when the switch is to be utilized in an application where signal quality is important. This will generally be the case where redundancy is employed.
FIG. 3 illustrates a single pole double throw switch 300 having first arm 301 and second arm 302. Each of arms 301, 302 is illustrated as employing three sections 111, 121 and 131 having the same configuration as described with respect to FIG. 2. The arms 301, 302 have a common input node Nl and an impedance matching element M10 between node Nl and input terminal 101.
FIG. 4 illustrates a single pole triple throw switch 400 having first arm 401, second arm 402 and third arm 403. Each arm is similar to the SPST arrangement illustrated in FIG. 2, and as in FIG. 3, node N1 is a common input node into each arm. Matching circuit M10 provides impedance matching for the switch input terminal 101.
While the present invention has been described with respect to various specific implementations of the invention, it is to be understood that the invention resides in the novel design approach rather than in the specific implementation described in this application. It is intended that the patent shall cover not only those implementations specifically disclosed, but also all obvious modifications and extensions thereof as well as the entire range of implementations encompassed by the claims appended hereto and the equivalents thereof. | An N-way redundant switch is implemented through the use of serial and parallel redundancy for providing redundancy in both ON and OFF operating modes. | 8 |
RELATED APPLICATIONS
This application claims the benefit of prior provisional application Ser. No. 60/503,124 under 35 U.S.C. § 119(e) and U.S. patent application Ser. No. 10/919,537 under 35 U.S.C. § 120 hereby specifically incorporated by reference in their entirety
STATEMENT REGARDING NOT APPLICABLE FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
REFERENCE A MICROFICHE APPENDIX
Not Applicable
FIELD OF THE INVENTION
This invention relates to ready-to-assemble components having brackets attached thereto and a method to use brackets to easily assemble components, such as furniture.
BACKGROUND OF THE INVENTION
Assembling furniture is ordinarily complicated. Present technology for assembling furniture is labor and part intensive. Presently, a piece of furniture will have many component parts and require several tools for assembly. Moreover, with present technology, assembly of furniture usually requires more than one person.
Other ready to assemble furniture systems utilize location dependent brackets that multiply the effort needed to assemble the furniture components and that intensify the complexity of the process.
Presently, most furniture is assembled by the seller because of the complexity of assembling. Thus, furniture is handled fully or most fully assembled which creates bulky cargo that takes up a considerable amount of space and is difficult to transport.
Additionally, when one part of a piece of furniture is damaged, the entire product must be returned instead of the damaged part. For example, when the frame of the arm of a couch is defective, the entire couch must be returned.
Regarding other ready-to-assemble furniture systems for furniture, all entail many component parts, are not stable and require considerable time to assemble. See e.g., Cwik U.S. Pat. No. 4,459,920 and Boycott, et al., U.S. Pat. No. 5,671,974.
BRIEF SUMMARY OF THE INVENTION
This invention further provides a method to assemble furniture having arm, base, seat and back components, which involves the steps of providing two arm components having a plurality of engaging and receiving brackets positioned to connect with corresponding brackets on another component; providing a base component having a plurality of receiving brackets positioned to connect with corresponding brackets on another component; providing a seat component with a plurality of brackets to connect with corresponding engaging brackets on another component; providing a back component with a plurality of engaging components to connect with corresponding receiving brackets on another component; connecting engaging brackets on the arm components with receiving brackets on the base component; connecting engaging brackets on the seat component with receiving brackets on the arm components; and connecting engaging brackets on the back component with receiving brackets on the arm components and the seat component.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a receiving bracket.
FIG. 2 is a schematic view of an engaging bracket.
FIG. 3 is a schematic view of a bracket assembly.
FIG. 4A is a schematic top view of a receiving bracket.
FIG. 4B is a schematic side view of a bracket assembly.
FIG. 4C is a schematic view of a receiving bracket and an engaging bracket.
FIG. 5A is a schematic top view of a receiving bracket and a compressible material.
FIG. 5B is a schematic side view of a receiving bracket and a compressible material.
FIG. 5C is a schematic view of a receiving bracket and a compressible material.
FIG. 6A shows a schematic view of the assembly process involving two arm components and a base component.
FIG. 6B shows the result achieved by the assembly of two arm components and a base component.
FIG. 7A shows a schematic view of the assembly process involving the seat component and the result in FIG. 6B .
FIG. 7B shows the result achieved by the assembly of the seat component, the base component and two arm components.
FIG. 8 shows a schematic view of the assembly process involving the back component and the result in FIG. 7B .
FIG. 9 shows the result achieved by the assembly of the back component, the seat component, the base component and two arm components.
FIG. 10A shows a schematic view of a connected table support connector.
FIG. 10B shows a schematic view of a disconnected table support connector.
FIG. 11A shows a schematic view of a connected headboard and bedrail.
FIG. 11B shows a top schematic view of a headboard and bedrail.
FIG. 11C shows a front schematic view of a headboard and bedrail.
FIG. 11D shows a right schematic view of a headboard and bedrail.
FIG. 12A shows a schematic side view of a receiving bracket and pole.
FIG. 12B shows a schematic side view of a sign connected to a pole via a bracket assembly.
FIG. 12C shows a schematic view of a sign with engaging bracket and pole with receiving brackets.
FIG. 13A is a schematic view of a portion of a casket.
FIG. 13B is a schematic view of a portion of a casket.
FIG. 13C is a schematic view of a portion of a casket.
FIG. 13D is a schematic view of a portion of a casket.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIGS. 1-3 , the bracket assembly 5 is made of a receiving bracket 2 and an engaging bracket 4 . Now referring to FIG. 1 , a receiving bracket 2 is made of a riser 34 . The riser 34 has an inner surface 44 and an outer surface 45 . The riser 34 may be straight, orthogonal, horizontal, sloped or curved. The riser 34 forms hollow internal section 20 . The receiving bracket 2 also includes a plurality of flanges 1 and 3 .
In the preferred embodiment, two coplanar parallel flanges 1 and 3 perpendicularly extend from the riser 34 . In the preferred embodiment, two spaced apart vertical members 34 A extend from a receiving top member 35 to form the riser 34 . In this embodiment, the vertical riser 34 A is straight and orthogonal. Receiving brackets 2 are preferably two and a half inches in width and two inches in length, but may be any size as desired by one skilled in the art. Receiving brackets 2 are preferably made of steel or iron although other materials, such as plastic or a synthetic modification thereof, may be used as desired by one skilled in the art. The engaging bracket 2 can be made integrally with a component.
In a preferred embodiment, the receiving bracket 2 is made of at least one planar flange 1 having an aperture 6 to receive an attachment means, such as a bolt, but other attachment means, such as spot welding or clamping, may be used as desired by one skilled in the art. At least one aperture 6 is preferably positioned in the center of each of the substantially parallel flanges 1 and 3 allowing for the receiving bracket 2 to be attached to a component (not shown in FIG. 1 ). A lock-down aperture 22 is positioned on the receiving bracket 2 to allow a locking means, such as a bolt, to contact the engaging bracket 4 to form a secure bracket assembly 5 , but any other locking means may be used as desired by one skilled in the art. In this way, one bracketed component is interconnected with a second bracketed component.
Referring to FIG. 2 , an engaging bracket 4 is made of an elongated riser 36 having an inner surface 46 and an outer surface 47 . The elongated riser 36 may be straight, orthogonal, horizontal, sloped or curved. A plurality of flanges 23 and 24 perpendicularly extend from the elongated riser 36 . The plurality of flanges 23 and 24 form a line of intersection 48 with the elongated riser 36 . The elongated riser 36 is configured to extend beyond the plurality of flanges 23 and 24 to form a cantilevered projection 39 . The cantilevered projection 39 is made of two portions. A first portion 40 and a second portion 41 . In the first portion 40 , the line of intersection 48 extends past the plurality of flanges 23 and 24 to form an outer surface sized to contact the inner surface 44 of the receiving bracket 2 . Additionally, the cantilevered projection 39 has a second portion 41 which tapers and narrows where the line of intersection 48 has been cut away allowing for easy assembly of the engaging bracket 4 and receiving bracket 2 .
In the preferred embodiment, two coplanar parallel flanges 23 and 24 extend from two spaced apart vertical members 36 A. In the preferred embodiment, the two spaced apart vertical members 36 A are straight and orthogonal. The spaced apart vertical members 36 A extend from the engaging top member 38 . The term riser can refer generically to a bracket having an external surface and a hollow internal section. More specifically, the terms two spaced apart vertical members refer to the preferred embodiment where the riser 36 is formed from two spaced apart members 36 A and a top member 38 .
Engaging top member 38 projects beyond at least one flange 23 to form a cantilevered projection 39 . The cantilevered projection 39 has a tapered guide portion 41 to allow ease of initial assembly between engaging bracket 4 and receiving bracket 2 . The cantilevered projection 39 is sized to fit, with minimal clearance in receiving bracket internal section 20 . In the preferred embodiment, the engaging bracket 4 is made of at least one planar flange 23 having an aperture 11 to receive attachment means, such as a bolt. Any other attachment means, such as spot welding or clamping, may be used as desired by one skilled in the art. In the preferred embodiment, two coplanar parallel flanges 1 and 3 of the receiving bracket 2 off-set two coplanar parallel flanges 23 and 24 of the engaging bracket 4 upon assembly. Engaging brackets 4 are preferably two and a half inches in width and four inches in length but can be any size as desired by one skilled in the art. Engaging brackets 4 are made of steel or iron although other materials, such as plastic or a synthetic modification thereof, may be used as desired by one skilled in the art. The described shape of the receiving bracket 2 and engaging bracket 4 are constant but the overall size may change. The receiving bracket 2 can be integrally made with the component.
Now referring to FIG. 3 , a bracket assembly 5 is shown. The bracket assembly 5 is formed of a receiving bracket 2 and an engaging bracket 4 which are placed in contact. The stability of the bracket assembly 5 is based upon contact between the outer surface 47 of elongated riser 36 of the engaging bracket 4 and the inner surface 44 of riser 34 of the receiving bracket 2 . Additionally, the stability of the bracket assembly 5 is based on contact between the first portion 40 of the cantilevered projection 39 of the engaging bracket 4 with the inner surface 44 of the riser 34 of the receiving bracket 2 . Additionally, the stability of the bracket assembly 5 can be based on contact between outer surface 45 of riser 34 of the receiving bracket 2 being in contact with the surface onto which the receiving bracket 2 is mounted.
Now referring to FIGS. 4A-C , alternative engaging and receiving brackets are shown. The inner surface 44 and riser 34 of the receiving bracket 2 are sized to contact the outer surface 45 of the engaging bracket 4 . In particular, the stability of the bracket assembly 5 is increased by the contact of the inner surface 44 of the receiving bracket 2 with the first portion 40 of the cantilevered projection 39 of the engaging bracket 4 .
Additionally, the strength of the bracket assembly 5 can be increased by providing an interference fit between the receiving bracket 2 and engaging bracket 4 . An interference fit occurs when the receiving bracket 2 is mounted on a material, such as wood. Wood will compress on the open side 20 of receiving bracket 2 to create a tight fit. Additionally, an interference fit occurs when the receiving bracket 2 is mounted to a material dissimilar to the engaging bracket 4 material. Similarly, a compressible layer of material, such as rubber can be placed between the receiving bracket 2 and the material to which the receiving bracket 2 is mounted.
Now referring to FIGS. 5A-C , the interference fit can be enhanced by relying on the compressibility of the material onto which the receiving bracket 2 is mounted, such as wood. Wood will compress on the open side 20 of the receiving bracket 2 to create a tight fit. Similarly, a compressible layer of material 50 can be placed between the receiving bracket and the material onto which the receiving bracket 2 is mounted if the material to which the bracket is mounted, i.e., steel, has inadequate compressibility for this purpose.
The bracket assembly 5 is further strengthened by lock down aperture 22 wherein a locking means such as a bolt is used to secure the receiving bracket 2 to engaging bracket 4 . Any other locking means may be used as desired by one skilled in the art. The lock down aperture 22 is positioned to allow a locking means, such as a bolt to contact the cantilevered portion 39 of engaging bracket 4 .
The receiving bracket 2 and engaging bracket 4 are attached to panels which are formed into components. The components assemble to form furniture, signage and caskets. The terms “receiving” and “engaging” when used to describe a bracket refer to the shape of a bracket and not to the motion of the assembly process. A furniture component is at least one panel having at least one engaging or receiving bracket attached thereto. In a preferred embodiment, a furniture component is made of a plurality of panels. A furniture component is fixedly attached to another furniture component by forming bracket assemblies 5 between the furniture components. The furniture components with at least one engaging or receiving bracket are referred to as a bracketed furniture components. A furniture component is the basic building block of this system. Furniture will be shipped as bracketed furniture components.
Now referring to FIGS. 6A-9 , the system and method to assemble a chair is shown. In this illustrative embodiment, the ready to assemble furniture piece 25 is made of five basic furniture components 10 , 12 , 14 and 16 including two opposing arm components 10 , a base component 12 , a seat component 14 , and a back component 16 . Depending on the styling of the furniture, more or less components can be used. These components are interconnected through receiving brackets 2 and engaging brackets 4 attached to the panels or made integrally with the panel. The bracketed furniture components 10 , 12 , 14 and 16 are preferably made of a plurality of furniture panels, such as 7 , 8 , 9 , 13 and 14 . A furniture component may be made of single panel as desired by one skilled in the art. A furniture panel is any part of the frame in which a bracket is attached, but not limited to wood; a panel can include other materials, such as steel and aluminum for example. Receiving brackets 2 and engaging brackets 4 are attached to the furniture components 10 , 12 , 14 and 16 in designated positions depending on the type and design of the ready to assemble furniture piece 25 desired. The brackets 2 and 4 are not location dependent. One skilled in the art may place the engaging brackets 4 and receiving brackets 2 at any location on the furniture components that allows for the furniture components to be interconnected by forming bracket assemblies 5 . The brackets can be attached anywhere on the panels as long as they position interlock with a corresponding bracket on another component. The number, shape and size of the arm components 10 , the base component 12 , the seat component 14 and back component 16 will vary depending on the type and design of the ready-to-assemble furniture piece 25 desired. Also, the number of total bracket assemblies 5 used to interconnect furniture component will vary as desired by one skilled in the art. The number of receiving brackets 2 and engaging brackets 4 attached on the furniture panels 7 , 8 , 9 , 13 and 15 will vary depending on the type and design of the ready-to-assemble furniture piece 25 desired.
A ready to assemble furniture piece 25 could be made of different bracketed components than those disclosed in this illustrative embodiment. For example, the bracketed component could be a table top, table leg, cabinet back, cabinet front, cabinet drawers, etc.
Referring to FIG. 6A , a portion of chair or small couch is shown. More specifically, two furniture arm components 10 are shown. The arm components 10 are made of differing materials and vary in size depending on the type and design of the ready to assemble furniture piece 25 desired. The arm component 10 is made of three major elements: a back side arm panel 7 , a front side arm panel 17 ; and a side arm panel 8 . A back side arm panel 7 includes a means to support a receiving bracket, such as a substantially perpendicular member 26 . The receiving bracket 2 is attached by nails through aperture 6 to the perpendicular member 26 , but other attachment means may be used as desired by one skilled in the art. The receiving bracket 2 of the back side arm panel 7 is preferably attached between the middle and top of the back side arm panel 7 . The front side arm panel 17 is substantially parallel to the back side arm panel 7 and is connected to the side arm panel by a plurality of support members 27 . The side arm panel 8 is substantially perpendicular to the back side arm panel 7 and front side arm panel 17 , and is connected to both. The side arm panel has a plurality of receiving brackets 2 and a plurality of engaging brackets 4 attached thereto. The brackets are positioned to connect with corresponding brackets on another furniture component to form a bracket assembly. A bracket assembly can be strengthened by applying an adhesive, bolt or screw to lock down aperture 22 . The base component 12 is made of a first side base panel 9 and a second side base panel 30 . The base component 12 is also made of a front base panel 28 and a rear base panel 29 . The first side base panel 9 and second side base panel 30 has an interior and exterior surface to which engaging brackets 4 and receiving brackets 2 are attached.
FIG. 6B depicts the result achieved by the assembly of two opposing arm components and a base component 12 . More specifically, two arm components 10 are contactingly moved adjacent to base component 12 . A plurality of engaging brackets 4 attached to the horizontal side arm panel 8 are inserted into receiving brackets 2 on the exterior surface of the first side base panel 9 and second side base panel 30 of the base component 12 .
Referring to FIG. 7A , the seat component 14 is made of a first and second side seat panels 13 . A plurality of engaging brackets 4 are vertically mounted on the exterior of each side seat panel 13 . In the preferred embodiment, two sets of engaging brackets 4 are attached near the front and rear sections of the side seat panels 13 allowing for the seat component 14 to lock with the arm components 10 upon assembly. The seat component 14 also includes a front seat panel 31 and rear seat panel 32 . The seat panels 13 , 31 and 32 are interconnected at right angles to form a frame. The receiving brackets 2 on the horizontal side arm panel 8 , and arm component 10 are positioned to receive engaging bracket 4 on side seat panel 13 of seat component 14 .
FIG. 7B depicts the result achieved by the assembly of the seat component 14 , the base component 12 and the two opposing arm components 10 .
Referring to FIG. 8 , the back component 16 is made of two side back panels 15 . An engaging bracket 4 is vertically mounted on the exterior of each side back panels 15 near the middle section of each side back panel 15 allowing for the back component 16 to interconnect with the arm components 10 upon assembly. An engaging bracket 4 is vertically mounted on the interior of the side back panels 15 in the lower section of each side back panel 15 allowing for the back component 16 to lock with the base component 12 upon assembly. The back component 16 is further made of a back panel 33 that is substantially perpendicular and attached to the two side back panels 15 .
FIG. 9 depicts the ready to assemble furniture piece 25 . The ready to assemble furniture piece 25 , a chair, is preferably made of furniture components 10 , 12 , 14 and 16 including the back component 16 , the seat component 14 , the base component 12 and two arm components 10 . Each furniture component 10 , 12 , 14 and 16 is made of furniture panels 7 , 8 , 9 , 13 and 15 which are preferably wooden but may be made of other materials, as desired by one skilled in the art. The furniture components can be upholstered, allowing the brackets to be attached to the exterior of the upholstery or can be upholstered when assembled.
The furniture components 10 , 12 , 14 and 16 are assembled by interconnecting the receiving brackets 2 and engaging brackets 4 which together form bracket assemblies 5 . The number of bracket assemblies 5 used will vary depending on the styling of the furniture. At least one receiving bracket 2 or engaging bracket 4 is attached to furniture panels 7 , 8 , 9 , 13 and 15 of each furniture component 10 , 12 , 14 and 16 .
In relation to the presently illustrative configuration, it should be understood that the ready to assemble furniture piece 25 is readily adaptable to all types of furniture pieces including but not limited to sofas, sleepers, loveseats, chairs, and motion furniture. Moreover, the ready to assemble furniture piece is readily adaptable to most types and designs of furniture including but not limited to leather, fabric, show wood, loose cushion, single cushion, single back and split back. This system is not exclusively intended for upholstered furniture use, but can be used in other areas of the furniture industry, such as cabinets and tables.
More specifically, as shown in FIGS. 10A and 10B a table support connection is shown. The table support 81 has a plurality of receiving brackets 2 attached around the table support 81 . A table leg 83 has an engaging bracket 4 attached. The receiving bracket 2 and engaging bracket 4 are positioned to allow the table leg 83 to connect with table support 81 .
In the preferred embodiment, there are four receiving brackets 2 attached equidistantly around the table support 81 , but more or less brackets may be used as desired by one skilled in the art. The four receiving brackets 2 are connected to four engaging brackets 4 to affix the table legs 83 to a table support 81 .
Additionally, in FIGS. 11A-D , bedpost and bedrail connections are shown. In FIG. 11A , a bedrail 93 is attached by a bracket assembly 5 to a bedpost 91 . FIGS. 11B-11D show cutaway sections of the connection viewed from above ( FIG. 11B ), the side ( FIG. 1 IC) and along the axis of the bedrail ( FIG. 11D ).
In FIGS. 12A , 12 B and 12 C, signage connection is shown. More specifically, a pole 101 has a receiving bracket 2 attached thereto. An engaging bracket 4 is attached to the back surface of a sign 103 . The sign is attached to the pole 101 through bracket assembly 5 .
Referring to FIGS. 13A-D , the receiving brackets 2 and engaging brackets 4 can be used to assemble a casket. In FIG. 13D , a bracket assembly 5 combines the components to form a casket.
The bracket assembly and system is advantageous because it allows the assembly of all types of furniture by a single individual. Moreover, the present invention is advantageous because it allows assembly at any place with no tools required for assembly and in approximately one to two minutes. Unlike present technology which is complicated and labor and part intensive, the self-assembly bracket and system has no loose parts to assemble. The required hardware for the present invention is only the receiving brackets 2 and engaging brackets 4 placed at integral parts on the ready to assemble furniture piece 25 .
Although the forgoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will be obvious that certain changes and modifications can be made which are within the full scope of the invention. | Unique brackets, which form a bracket assembly that may be placed at any location of various components to form an assembly piece, such as furniture are disclosed. An assembled furniture piece made of furniture panels interconnected with attached engaging and receiving brackets is provided. The engaging and receiving brackets are positioned on components to facilitate the connection of the components. A method to assemble furniture having preformed arm, base, seat and back components is provided. This method of assembly saves on shipment costs, and facilitates the repair of damaged furniture. | 8 |
BACKGROUND
In downhole completion systems using Electric Submersible Pumps (ESPs), there is sometimes the need to retrieve the ESP to surface for repair or replacement. The ESP will be a part of an upper completion that will be retrieved as a unit when retrieval of the ESP is required. This will leave a lower completion in the borehole and hence require that a barrier be actuable to seal off the lower completion. Commonly, a valve is positioned near an uphole extent of the lower completion for this purpose. The valve is actuated usually hydraulically. When replacing the most recently installed completion it is necessary to use a wet connect arrangement to reconnect to the hydraulic control lines of the original barrier valve. While wet connect arrangements are well known and often used in the downhole environment, they are also potentially finicky and hence may not always be favored by operators. The art would therefore well receive alternate systems that increase the ease with which post retrieval valve actuation is achieved.
BRIEF DESCRIPTION
Disclosed herein is a barrier valve system which includes one or more barrier valves, a connection sub having a first portion and a second portion connecting one or more control lines to each other, and a replacement portion of the connection sub connectable to the first portion subsequent to retrieval of the second portion. The replacement portion has a port from an outside diameter of the replacement portion to an inside diameter of the replacement portion and seals disposed to define an annular space between the replacement portion and the first portion encompassing only valve opening ports in the first portion.
Also disclosed herein is a barrier valve system which includes one or more barrier valves and a connection sub having a first portion and a second portion connecting one or more control lines to each other. A replacement portion of the connection sub is connectable to the first portion subsequent to retrieval of the second portion, and the replacement portion is configured to convey applied tubing pressure to the one or more valves such that the one or more valves actuate to an open condition.
Further disclosed is a method for retrieving and reconnecting an upper completion which includes closing one or more barrier valves in a lower completion proximate a downholemost end of the upper completion, retrieving the upper completion, reconnecting one of the original upper completion or a new upper completion to the lower completion by stabbing a replacement portion into a first portion of a connection sub connected to the lower completion, and applying tubing pressure through the replacement portion to the first portion of the connection sub and to the one or more barrier valves thereby opening the one or more barrier valves.
BRIEF DESCRIPTION OF THE DRAWINGS
The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
FIG. 1 is a schematic view of a barrier system; and
FIG. 2 is a schematic view of a reconnect system operable with the FIG. 1 barrier system.
DETAILED DESCRIPTION
A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
Referring to FIG. 1 , an exemplary borehole completion 8 including a barrier valve system 10 is illustrated. The completion 8 includes a lower completion 12 having a packer 14 , and part of the barrier valve system 10 having one or more barrier valves 16 (illustrated as two but not limited to two) proximate an uphole extent of the lower completion 12 . The barrier valve system 10 itself comprises the one or more barrier valves 16 , control lines 18 , 20 , 22 and an annular connection sub 26 , all of which are discussed hereunder. The barrier valves 16 are in operable communication with the control lines 18 , 20 and 22 (in this exemplary embodiment, more or fewer are contemplated). The control lines 18 , 20 and 22 terminate at a first portion 24 of the annular connection sub 26 having ports 28 , 30 and 32 extending radially of the portion 24 of the sub 26 . The portion 24 of the sub 26 is interactive with a second portion 34 of the connection sub 26 that is connected to an upper completion 36 . The second portion 34 also includes radial ports that are annularly in communication with the ports 28 , 30 and 32 . The ports of portion 34 are labeled 38 , 40 and 42 as three are shown but it is again noted that more or fewer are contemplated and that there are not necessarily the same number of ports on each portion of the connection sub 26 . Rather, depending upon where seals are located within the connection sub 26 , one or more control lines may be connected to one or more other control lines as desired. The connection sub is more fully described in U.S. Pat. No. 7,487,830, the entire disclosure of which is incorporated herein by reference.
It will be appreciated in FIG. 1 that the connection sub 26 includes a number of seals (illustrated as four in FIG. 1 ) 44 , 46 , 48 , 50 that separate various port connections from each other. This provides in the illustrated embodiment three control lines extending from the upper completion (likely to surface) to the lower completion. It is to be appreciated that the seals are mounted to the portion 34 so that they are removed from the connection sub 26 upon retrieval of the upper completion 36 . This is important to functionality of the system herein described as will be more apparent in the discussion below. As illustrated the three lines are for a common close line that will close all barrier valves of the lower completion upon pressure applied therein and two open lines that will selectively open each of the illustrated barrier valves. The installed system 10 will work appropriately in this configuration.
Upon retrieval of an ESP 52 along with the upper completion 36 , the barrier valves 16 will need to be closed to prevent downhole fluids escaping the completion through an open upper extent of the lower completion 12 . This will be accomplished by pressuring the common control line 18 for closure of the valves 16 . The upper completion 36 may then be withdrawn from the borehole. Upon reintroducing a new upper completion 36 or the original one, the barrier valves 16 must be reopened to reestablish flow potential through the borehole completion system 10 . Wet connection as noted above can be problematic and hence the inventor hereof has devised a way to simplify reconnection using a much easier to connect configuration and applied tubing pressure for actuation of the valves 16 .
More specifically, and referring to FIG. 2 , a schematic illustration of the reconnect configuration is presented. Reference is made to first portion 24 of connection sub 26 for continuity from the previous discussion. This portion of the connection sub 26 does not change. Moreover, the reader is reminded that the seals were removed with the second portion 34 of the connection sub 26 when the upper completion was retrieved from the borehole leaving the first portion 24 a seal bore. The replacement portion 54 of the connection sub 26 presents seals 56 and 58 in a different position than the seals 44 , 46 , 48 , 50 were in with the original portion 24 of connection sub 26 . Rather, seals 56 and 58 are positioned on either side of a port 60 through the replacement portion 54 to an inside diameter thereof such that tubing pressure is ported to a space between seals 56 and 58 .
It was noted above that as an exemplary embodiment, the illustrated configuration has two open lines and a common close line. The ports for these lines are in portion 24 and are labeled 62 , 64 and 66 . The replacement portion 54 does not use the common close line port 66 as can be seen in the drawing, as it is not within the annular space defined by the seals 56 and 58 . The ports 62 and 64 are however located between the seals 56 and 58 on replacement portion 54 when the replacement portion is landed in portion 24 . This allows the system to provide tubing pressure to the two “open” ports 62 and 64 and through those open the barrier valves 16 that had been closed prior to retrieving the ESP 52 and the upper completion 36 . These barrier valves 16 are to remain permanently open at this point. And the original (or previous) portion 24 is not again used to control the now permanently open valves 16 .
As can be seen in FIG. 2 , the replacement portion 54 is the downhole end of a new barrier valve system 110 having a packer 114 , one or more valves 116 , a first portion 124 and a portion 134 of a connection sub 126 and control lines equivalent to those described above. This system 110 is affixed to a downhole end of a new or re-run upper completion string 136 and new or repaired ESP 152 . The system provides for a very simple and tolerant wet connect that uses only tubing pressure to actuate previously closed valves 16 to the open position where they will remain pursuant to the addition of one or more new barrier valves 116 to replace the function of the previous ones should the need arise to retrieve the ESP 152 again. Potential pitfalls of conventional wet connect arrangements are avoided through the use of the applied tubing pressure based concept disclosed herein.
While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item. | A barrier valve system includes one or more barrier valves, a connection sub having a first portion and a second portion connecting one or more control lines to each other, and a replacement portion of the connection sub connectable to the first portion subsequent to retrieval of the second portion. The replacement portion has a port from an outside diameter of the replacement portion to an inside diameter of the replacement portion and seals disposed to define an annular space between the replacement portion and the first portion encompassing only valve opening ports in the first portion. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to well logging methods and apparatus and more particularly to nuclear well logging techniques to determine the presence of undesired water flow in cement voids or channels behind steel well casing in a cased well borehole as well as flow in the borehole and adjacent tubing.
2. Description of the Related Art
Undesired fluid communication along the cased portion of a well between producing zones has long been a problem in the petroleum industry. The communication of fresh or salt water from a nearby water sand into a petroleum production sand can contaminate the petroleum being produced by the well to an extent that production of petroleum from the well can become commercially unfeasible due to the “water cut”. Similarly, in near surface water wells used for production of fresh water for city or town drinking supplies or the like, the contamination of the fresh water drinking supply by the migration of salt water from nearby sands can also contaminate the drinking water supply to the extent where it is unfit for human consumption without elaborate contaminant removal processing.
In both of these instances, it has been found through experience over the course of years that the contamination of fresh water drinking supplies or producing petroleum sands can occur many times due to the undesired communication of water from nearby sands down the annulus between the steel casing used to support the walls of the borehole and the borehole wall itself. Usually steel casing which is used for this purpose is cemented in place. If a good primary cement job is obtained on well completion, there is no problem with fluid communication between producing zones. However, in some areas of the world where very loosely consolidated, highly permeable sands are typical in production of petroleum, the sands may later collapse in the vicinity of the borehole even if a good primary cement job is obtained. This can allow the migration of water along the outside of the cement sheath from a nearby water sand into the producing zone. Also, the problem of undesired fluid communication occurs when the primary cement job itself deteriorates due to the flow of fluids in its vicinity. Similarly, an otherwise good primary cement job may contain longitudinal channels or void spaces along its length which permit undesired fluid communication between nearby water sands and the producing zone.
Another problem which can lead to undesired fluid communication along the borehole between producing oil zones and nearby water sands is that of the so called “microannulus” between the casing and the cement. This phenomenon occurs because when the cement is being forced from the bottom of the casing string up into the annulus between the casing and the formations, (or through casing perforations), the casing is usually submitted to a high hydrostatic pressure differential in order to force the cement into the annulus. The high pressure differential can cause casing expansion. When this pressure is subsequently relieved for producing from the well, the previously expanded casing may contract away from the cement sheath formed about it in the annulus between the casing and the formations. This contraction can leave a void space between the casing and the cement sheath which is sometimes referred to as a microannulus. In some instances, if enough casing expansion has taken place during the process of primary cementing (such as in a deep well where a high hydrostatic pressure is required) the casing may contract away from the cement sheath leaving a microannulus sufficiently wide for fluid to communicate from nearby water sands along the microannulus into the producing perforations and thereby produce an undesirable water cut.
U.S. Pat. No. 4,032,780 to Paap et al. teaches a method of determination of the volume flow rate and linear flow velocity of undesired behind casing water flow is provided. A well tool having a 14 MeV neutron source is used to continuously irradiate earth formations behind well casing. The continuous neutron irradiation activates elemental O 16 nuclei in the undesired water flow to be detected. Dual spaced gamma ray detectors located above or below the neutron source detect the decay of unstable isotope N 16 and from these indications the linear flow velocity of the undesired water flow is deduced. By then estimating the distance R to the undesired flow region the volume flow rate V may be deduced.
U.S. Pat. No. 5,461,909 to Arnold teaches a modification of the Paap technique in which the linear flow velocity, the Full Width Half Maximum time period, and the total count are determined directly from the resulting count rate curve. The radial position and the flow rate are determined using the predetermined relationship between the Full Width Half Maximum time period, radial position, and linear flow velocity, and the predetermined relationship between linear flow velocity, radial position, and the ratio of the flow rate to the total count for the logging tool. The direction of flow is determined by sensing the presence or absence of flowing N 16 above or below the source.
The references discussed above do not address the problem of more than one type of fluid flowing in the borehole. U.S. Pat. No. 5,404,752 to Chace et al. teaches a method for measuring the velocities of water volumes flowing co-directionally in separate conduits nested such as in injection or production well-bores. The method allows an oxygen activation measurement of the velocity of the water flow in the tubing-casing annulus in the presence of water flowing in the tubing string in the same direction. The method allows continuous logging at variable or constant cable velocities or stationary logging. Based on the method of velocity gauging, the method isolates the signal from the annular flow and can produce a continuous log of linear and volumetric annular flow rates with depth.
The methods discussed above are based on measurements of total counts within a specified energy window. As noted above, the method of Paap requires continuous irradiation. The method of Arnold uses a pulsed neutron source and requires correction for the background signal. In Arnold and in Chace, pulsing is carried out at relatively high frequencies. The method of Chace, when applied to dual flow, first determines an inner flow rate and then uses this determined inner flow rate for determination of an outer flow rate. It would be desirable to have a method in which such correction for background signals and the sequential determination of flow rates is not necessary. The present invention addresses this need.
SUMMARY OF THE INVENTION
The present invention is a method of and an apparatus for determining a flow velocity of a first fluid in a borehole in an earth formation. The earth formation is irradiated with a pulsed radiation source. A first temporal signal and a second temporal signal are determined from measurements made by a first and second detector spaced apart from each other and from the source. The radiation source may be a pulsed neutron source that activates nuclei of O 16 in the fluid to N 16 . The subsequent decay of N 16 produces gamma rays that may be measured by the two detectors. In one embodiment of the invention, both detectors respond to the produced gamma rays, in which case the distance between the two detectors is used in the velocity determination. In an alternate embodiment of the invention, one of the detectors responds immediately to inelastic and capture events, in which case, the distance between the source and the second detector is used for velocity determination
The velocity determination may be based on a correlation of the first and second temporal signals. A surface or downhole processor may be used for the velocity determination. The temporal signals may be scaled. Alternatively, the velocity determination may be based on correlation of time derivatives of the first and second temporal signals. The first and second temporal signals comprise accumulated counts of detector measurements over a time sampling interval. Use of a third detector makes possible determination of flow velocities of two fluids in the borehole. The fluids in the borehole may be within a tubing or in an annulus outside a casing within said borehole. Optionally, semblance methods may be used for analysis of the temporal signals.
With proper calibration, a volumetric flow rate of the fluids may be determined. Once the volumetric flow rate and the flow velocity are known, an effective area of flow may be determined. In an optional embodiment of the invention, effective distances may be used instead of the actual distances to account for differences between the leading and trailing edges of the temporal signals. Calibration is needed to establish the effective distances.
The radiation source is typically pulsed at regular intervals. To avoid aliasing problems, random pulsing may be used. An alternate embodiment of the invention alters a duration of the pulsing at a predetermined interval to avoid aliasing.
BRIEF DESCRIPTION OF THE FIGURES
The present invention is best understood with reference to the accompanying figures in which like numerals refer to like elements, and in which
FIG. 1 (prior art) is an exemplary schematic diagram of an apparatus suitable for use with the method of the present invention;
FIG. 2 (prior art) is an enlargement of that portion of FIG. 1 involving the logging instrument;
FIG. 3 is a schematic illustration of temporal signals (after normalization) measured at two spaced apart detectors;
FIG. 4 illustrates a situation where the near detector is immediately responsive to source activation;
FIG. 5 illustrates an embodiment of the invention wherein differentiation of the signals is carried out;
FIG. 6 illustrates a configuration for detection fluid flow in two different directions;
FIGS. 7 a – 7 c illustrate an embodiment of the invention simulating a prior art steady state method; and
FIG. 8 illustrates a method for determination of flow volume.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 and 2 represent a cross section of a portion of an injection well penetrating a subsurface formation 10 to a region associated with an injection zone 12 . Casing 14 includes multiple perforations 16 opposite the porous injection zone 12 . Injection tubing 18 , nested inside casing 14 is provided with openings 19 so that the injection fluid flows under pressure into the annulus 20 between the inner conduit or tubing 18 and outer conduit or casing 14 , thence into the formation via the perforations 16 to sweep oil towards a production well (not shown). Packers 13 and 15 confine the injection water in casing 14 to a desired production zone 12 . The water flow volumes in the annulus and in the tubing are co-directional as shown by the arrows V 1 and V 2 respectively though this is not a limitation of the method of the present invention. The velocity of the logging instrument 22 is symbolized by arrow Vc (velocity of cable).
The logging instrument 22 is a modification of a conventional neutron logging instrument. It comprises an elongated mandrel 24 of suitable material supported by a cable 26 that is coupled to the draw works 27 at the surface for deployment through the inner conduit or injection tubing 18 . The velocity of the instrument 22 as it is drawn through the conduit 18 is measured by an odometer/velocimeter of any well known type 29 that may be associated with a sheave over which the supporting cable 26 passes.
A pulsed neutron source 28 is mounted inside one end of the instrument 22 and separated from interiorly-mounted near and far gamma ray detectors 30 and 32 by a shield 34 . A third gamma ray detector 36 may be provided. It is to be understood that the detectors may be mounted beneath the source as shown in FIG. 1 or above the source, or any combination thereof, i.e., at least one below and at least one above. The selection of the configuration depends upon the direction of the water flow to be measured. A mechanical flowmeter 40 is secured to the bottom of the instrument 22 for measuring the velocity of the fluid in the inner conduit relative to the instrument. Signal processing electronic circuitry (not shown) is installed in compartments of the instrument to discriminate against low level gamma ray activity in favor of the higher energy deriving from the activated oxygen. The detector count rates are digitized downhole and are telemetrically transmitted to the surface through suitable conductors in supporting cable 26 to processing and archival storage unit 31 at the surface. Optionally, a satellite communication link (not shown) may be provided with the data being transmitted to a remote location. In one embodiment of the invention, four detectors may be provided at distances of 1, 2, 4 and 12 ft. In an alternate embodiment of the invention, a processor is provided downhole.
In prior art methods, such as that in Chace, the neutron source is pulsed at 1 kHz for 28 milliseconds (ms) and is then shut off for 8 ms during which time the count rate measurement is made. In contrast, in the present invention, the neutron source may be ramped up to a maximum level over a ten second interval, maintained at a substantially constant value for twenty to forty seconds or so, and then ramped down over a ten second interval. Alternatively, the source activation and deactivation may be substantially instantaneous. Each of the detectors measures count rates or signals. Count rates from each of the detectors are accumulated by a processor over a suitable time sampling interval. In one embodiment of the invention, the temporal sampling interval is 0.5 seconds. These count rates are made over a suitable energy level. In one embodiment of the invention, received gamma rays having energies above 3.5 MeV are counted. The upper limit of the energy window may be 18 MeV or so. The accumulated count rates define a temporal signal.
Turning now to FIG. 3 , the basic principle of the method of the present invention are described. Shown are curves 101 and 103 that depict temporal signals measured at two detectors. The abscissa is time and the ordinate is the accumulated count rate over the temporal sampling interval. As noted above, the time sampling interval is typically 0.5 seconds. For the case where there is only a single velocity of flow, the signal 101 corresponds to measurements made by a detector that is closer to the source than the detector that measured signal 103 . Since the signals are the result of radioactive decay of N 16 with a half life of about 7.13 seconds, the absolute level of the signal measured by the farther detector will be less than the absolute level of the signal measured by the closer detector. In the plot shown in FIG. 3 , suitable normalization of the signals has been done so that they appear to be of comparable amplitude. The spacing Δd between the near detector and the far detector is a known quantity. Hence by measuring the time delay Δt between signal 101 and signal 103 , a velocity of flow v r can determined by:
v
r
=
Δ
d
Δ
t
(
1
)
This determined velocity v r is a measurement of fluid velocity relative to the velocity of the logging tool v t . When the logging tool is stationary, then the velocity v r will be the same as the actual fluid velocity. When the logging tool is in motion, then the actual fluid velocity v f is given by:
v f =v r +v t (2)
where it is understood that the summation is a vector summation. For the remainder of the discussion of the method of the present invention, it is assumed that the logging tool is stationary, and that suitable correction for the velocity of motion of the tool can be made.
In one embodiment of the present invention, the time delay Δt is obtained by cross-correlation of the signals 101 and 103 . When the near detector is sufficiently far from the source, the signal 101 corresponds to the activation of O 16 to N 16 and the resulting gamma rays produced by decay of N 16 . However, if the near detector is sufficiently close to the source, it may respond immediately to the source activation due to inelastic and capture events. This is depicted in FIG. 4 wherein if the near detector D 1 ′ is within the region of inelastic or capture events denoted by 121 , then it responds immediately to the source activation. The far detector D 2 responds to the N 16 after a time delay corresponding to fluid flow from the source position to the detector position D 2 and the associated distance Δd′.
The time delay may also be obtained by identifying the point of inflection of signals from the rising and falling edge of signals 101 and 103 . This is shown in FIG. 5 where, as before, 101 and 103 are the signals at the two detectors. The curves 151 and 153 are the first derivatives with respect to time of the curves 101 and 103 . The time delay can then be obtained from Δτ 1 , the time delay between the peaks of 151 and 153 , or from Δτ 2 , the time delay between the troughs of 151 and 153 .
In another embodiment of the invention, fluid flow in any direction can be measured. This requires at least two gamma ray detectors disposed on opposite sides of the source for determining the decay signals from N 16 . These are denoted by D 2 and D 3 in FIG. 6 a . In addition, a single detector denoted by D 1 ′ responsive to inelastic signals resulting from the source activation is needed to provide a reference time. As an alternative to the single detector D 1 ′, the arrangement of FIG. 6 b can be used with two detectors responsive to N 16 decay signals on either side of the source.
Those versed in the art would recognize that in some respects, the signals received here at fixed source-detector distances and characterized by a velocity of transit, are similar to those in acoustic signals in boreholes. There is a well developed methodology for analysis of such acoustic signals based on semblance analysis. Also well developed is the so called tau-p transform where signals in the time—offset domain are transformed to the intercept time—slowness domain (slowness being the reciprocal of velocity). Semblance analysis or stacking of the transformed signals in the τ-p domain along lines of constant slowness (or velocity) is a well known method for identifying signals that have a linear moveout in the time-offset domain. These methods are particularly useful in differentiating between signals with different velocities of propagation. Such methods are well known in the art of acoustic signal processing and are not discussed herein. An example of such processing is given in U.S. Pat. No. 6,023,443 to Dubinsky et al., having the same assignee as the present invention and the contents of which are fully incorporated herein by reference. In the context of the present invention, these transform techniques are useful in processing of signals from multiple detectors and separating out fluid flows with possibly different directions and/or different velocities.
A hybrid technique may be used, whereby the data from the method can be processed slightly differently and used in the steady state velocity measurement method of prior art. If we integrate the count rates from each of two detectors during the time the activated water signal is present, correcting the counts for background, we can apply them into the following standard formula:
v f = v t + λ Δ d ln ( A B ) + ln ( D 1 D 2 ) ( 3 )
where A and B are the count rates from the detectors found by integration, Δd is the spacing between the detectors, v t is the logging speed and λ is the decay constant of activated Oxygen. The D terms are detector balance terms. This is illustrated schematically in FIGS. 7 a – 7 c . Shown in FIG. 7 a are illustrative signals 101 and 103 at two different detectors. FIG. 7 b shows signal 101 ′ with the area A indicative of total count rates for the near detector. FIG. 7 c shows signal 103 ′ and the count rates for the far detector.
The neutron source generating the neutrons does not act like a point source, i.e., the water it activates has a “length”. When the source is turned on, the water a small distance ahead of the source becomes activated and hits the detector slightly faster than water at the source position reaches the detector. Conversely when the source is switched off the water slightly behind the source is still activated and takes slightly longer to reach the detector than predicted. In one embodiment of the invention, an effective spacing shorter than the true spacing is used for the rising edge. Conversely, an effective spacing longer than the true spacing is used for the trailing edge. A calibration is performed by recording data in a static water-filled environment (in situ) while moving the instrument at a known constant speed. The instrument speed can then be used as the effective water velocity and the data processed to solve for the effective source to detector spacings for the rising and falling edges.
In one embodiment of the invention, the calibration is used to determine the volume of moving water. Calibration may be performed in an area of a borehole of known diameter that is substantially full of water: The water velocity is known and the count rate integrated from the data for that velocity can be obtained. Hence the response function which describes the count rate response of a detector with respect to water velocity can be determined and only varies with one other unknown variable, namely the source output. The data from the calibration which defines the count rate at a known velocity and volume of water for a fixed source output value. This makes it possible to fit the theoretical response to the data such that for any velocity calculated during a logging operation we can determine from the count rate the water volume present relative to the volume present during calibration. The volume is a ratio of count rates which have been corrected for velocity.
This is illustrated schematically in FIG. 8 . The curve 151 is a calibration curve showing the count rate as a function of flow velocity (for 100% water). As an example, if a flow velocity of 30 ft/min is measured, then if the flow were 100% water, the expected count rate would be given by N2. If an actual count rate of N1 is measured, then the water volume is simply given by the fraction N1/N2. Knowing the water volume and the flow velocity, an effective area of flow can be determined.
A potential source of error can occur when the activated oxygen takes longer to reach the detector than the time between source “on” periods. This can lead to false velocity determination by correlating the detector pulse with the wrong source on period. This is referred to in signal processing by the term “aliasing.” To prevent this mismatch from occurring, in one embodiment of the invention, for every N cycles of the source “on” cycle, the source activation is characterized by a unique synchronization signal. The number N may be any integer greater than, say 5 or so. Examples of such synchronization signals include (i) increasing the source “on” time by a predetermined factor, (ii) decreasing the source “on” time by a predetermined factor, and, (iii) skipping a source “on.” In another embodiment of the invention, the source activation time is random and actual activation cycle is available to the processor.
Those skilled in the art will devise other embodiments of the invention which do not depart from the scope of the invention as disclosed herein. Accordingly the invention should be limited in scope only by the attached claims. | A pulsed neutron source irradiates an earth formation. The irradiation produces N 16 from O 16 in a fluid in the borehole, and the gamma rays produced by the subsequent decay of N 16 are detected by a plurality of spaced apart detectors. The count rates of the detectors are accumulated over a time sampling interval to produce temporal signals. Processing of the temporal signals using correlation, differentiation and/or semblance techniques is used for determination of the flow velocity of one or more fluids in the borehole. | 4 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation of copending international application PCT/EP03/09894 filed on Sep. 5, 2003 and designating the U.S., which was not published under PCT Article 21(2) in English, and claims priority of German patent application DE 102 42 337.7 filed on Sep. 9, 2002, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to monoclonal antibodies for isolating and/or identifying neural progenitor cells.
[0004] 2. Related Prior Art
[0005] In contrast to many other tissues, the central nervous system has only a limited regeneration potential. Mature nerve cells which have died are not regenerated. Although neural stem cells are in fact present in the adult central nervous system (CNS), they have only a limited capacity to generate new, functionally active nerve cells after injuries.
[0006] There is for this reason great interest in the possibility of repairing the nervous system by transplanting new cells which can replace cells which have been lost through injury or disease.
[0007] At present, no suitable possibilities for remediation in particular of diseases or injuries associated with neurological deficits are available. Examples of such diseases are Parkinson's disease, Huntington's chorea, Alzheimer's disease, epilepsy, strokes or spinal cord injuries. Currently, transplantation appears to be the most promising form of therapy.
[0008] Because of the highly complicated architecture of the brain and the complex connections of the individual regions of the brain, cell replacement strategies in the nervous system make use of immature progenitor cells which must become incorpo-rated into the existing structures and do not differentiate until there.
[0009] Multipotent stem cells with the capacity of differentiating into neural cells have been found inter alia in the human central nervous system. Such neural progeni-tor cells express nestin as typical surface marker and are able to differentiate for example into neurons, oligodendrocytes and astrocytes.
[0010] Rao M S., “Multipotent and restricted precursors in the central nerv-ous system”, Anat. Rec. 257: 137 148 (1999), was able to isolate multipotent progenitor cells from adult human brain regions, including inter alia the temporal and frontal regions, the tonsils and the hippocampus. Moreover, Barami et al., “An efficient method for the culturing and generation of neurons and astrocytes from second trimester human central nervous system tissue”, Neurol. Res. 23: 321 326 (2001), showed that neural progenitor cells (NPC) from the central nervous system of human fetal tissue were CD133-positive and in addition were able to differentiate with epidermal growth factor (EGF), fibroblast growth factor and leukemia-inhibiting factor in vitro into neurons and astrocytes.
[0011] The cell surface marker CD133 was originally found on hematopoi-etic stem and progenitor cells, but more recent studies have shown that this marker is also expressed in various neural tissues and skeletal muscle tissues. For these reasons, this marker on its own is unsuitable for the purposes of distinguishing different stem or pro-genitor cells.
[0012] A great problem in the identification of neural progenitor cells is that neural progenitor cells and mesenchymal stem cells represent homogeneous populations in terms of morphology and phenotype. This is attributable in particular to the limited number of antigens investigated and identified to date.
[0013] Mesenchymal stem cells can be obtained and isolated from the bone marrow of adult humans. They are multipotent and contribute to the regeneration of bone, cartilage, tendons, muscles, adipose tissue and stroma.
[0014] Kopen et al., “Marrow stromal cells migrate throughout forebrain and cerebellum, and they differenciate into astrocytes after injection into neonatal mouse brains”, Proc. Nat. Acad. Sci. USA, 96: 10711 10716 (1999) and Brazelton et al., “From marrow to brain: expression of neuronal phenotypes in adult mice”, Science 290: 1775 1779 (2000), were in fact able to show that mesenchymal stem cells isolated from bone marrow were able to differentiate also into non-mesenchymal cells such as liver cells, neural and glial cells. In addition, it has been possible to show only recently that mesen-chymal stem cells from adult human bone marrow were able to differentiate into neural cells in vitro. Woodbury et al., “Adult rat and human bone marrow stromal cells differen-ciate into neurons”, J. Neurosci. Res. 61: 364 370 (2000), showed that in the presence of dimethyl sulfoxide (DMSO) and β-mercaptoethanol (BME) mesenchymal stem cells were able to differentiate into cells which expressed neurofilament and neuron-specific enolase.
[0015] Other research groups describe the differentiation of stromal bone marrow cells by means of epidermal growth factor and brain-derived neurotrophic factor (BDNF) into nerve cells which expressed nestin, glial fibrillary acidic protein (GFAP) and the neuron-specific nuclear protein (Neu N).
[0016] The fact that mesenchymal stem cells can also differentiate under certain conditions into nerve cells gives rise to the need to be able to distinguish neural progenitor cells from mesenchymal stem cells.
[0017] Despite the great interest, research on these neural progenitor cells has been greatly impaired by the lack of unambiguously defined markers for these cells. It is precisely the ability to identify relevant types of cells which first makes it possible to analyze the way in which the various cell populations of the central nervous system are generated.
[0018] Markers which are employed in particular for neural progenitor cells are antibodies against the protein nestin which is typically expressed by neural progenitor cells. However, this protein is also expressed by other cells such as, for example, astrocytes (see Clarke et al., “Reactive astrocytes express the embryonic intermediate neurofilament nestin”, Neuroreport 5: 1885 1888 (1994)) and muscle cells (see Sejersen and Lendahl, “Transient expression of the intermediate neurofilament nestin during skeletal muscle development”, J. Cell Sci. 106: 1291 1300 (1993)).
[0019] For these reasons, immunoreactivity with nestin is unsuitable as sin-gle criterion for identifying a particular cell as neural progenitor cell.
SUMMARY OF THE INVENTION
[0020] Against this background, it is an object of the present invention to provide monoclonal antibodies with which it is possible to identify and, where appropriate, to separate neural progenitor cells for example from a sample of a cell suspension.
[0021] This object is achieved according to the invention by an antibody or a fragment thereof which binds to the same antigen as an antibody produced by a hybri-doma cell line which is selected from the group consisting of the following hybridoma cell lines: W4A5, W8C3 and 57D2 which were deposited on Aug. 14, 2002, at the Deutsche Sammlung von Mikroorganismen und Zellkulturen (DSMZ) in accordance with the Budapest under the numbers DSM ACC2571, DSM ACC2570 and DSM ACC2568.
[0022] The object underlying the invention is completely achieved thereby.
[0023] The inventors were able to show in their own experiments that it is possible with the novel antibodies of the invention to isolate and to characterize neural progenitor cells in a selective manner.
[0024] The inventors have additionally succeeded in distinguishing neural progenitor cells from, for example, mesenchymal stem cells, with the aid of the novel antibodies in an outstanding fashion.
[0025] Another object of the present invention is an antibody or a fragment thereof which is produced by the hybridoma cell line W4A5 which was deposited in accordance with the Budapest treaty on Aug. 14, 2002, at the DSMZ under the number DSM ACC2571.
[0026] A further object of the present invention is an antibody or a fragment thereof which is produced by the hybridoma cell line W8C3 which was deposited in accordance with the Budapest treaty on Aug. 14, 2002, at the DSMZ under the number DSM ACC2570.
[0027] An additionally object of the present invention is an antibody or a fragment thereof which is produced by the hybridoma cell line 57D2 which was deposited in accordance with the Budapest treaty on Aug. 14, 2002, at the DSMZ under the number DSM ACC2568.
[0028] The inventors were able to generate the antibodies W8C3 and W4A5 by using the cell line WERI RB 1.
[0029] This cell line is a cell line isolated from a retinoblastoma and has, for example, the number DSMZ ACC 90 in the Deutsche Sammlung von Mikroorganismen und Zellkulturen. It was not to be expected—and there was no indication thereof in the art either—that it is possible with use of this cell line to generate antibodies for identifying neural progenitor cells.
[0030] The antibody 57D2 was generated by using the cell line TF 1.
[0031] This cell line is an erythroleukemia cell line which has for example the number DSMZ ACC 334 at the Deutsche Sammlung von Mikroorganismen und Zellkulturen. There is no evidence in the literature that it is possible by using this cell line to generate antibodies which are specific for neural progenitor cells and are therefore suitable for the identification and/or isolation thereof.
[0032] To this extent it was surprising that the antibodies W8C3, W4A5 and 57D2 bind to antigens which are characteristic of neural progenitor cells to such an extent that they provide an excellent opportunity for selective identification of neural progenitor cells from a sample comprising various cell populations. The cell lines used for immuniza-tion are already differentiated, which is why it was not to be expected that a multipotent neural progenitor cell would be recognized by the antibodies of the invention on the basis of its different surface markers.
[0033] The production of monoclonal antibodies by fusion of spleen cells from immunized mice and myeloma cells was described in 1975 by Kohler and Milstein (“Continuous cultures of fused cells secreting antibody of predefined specificity”, Nature 256: 495 497). The techniques for the chemical selection of the hybridomas resulting from such a fusion, and the subsequent isolation of cell clones which secrete single antibodies for the production of monoclonal antibodies are likewise known in the art.
[0034] The inventors have been able to show in their own experiments that the abovementioned antibodies are specific for neural progenitor cells. The inventors were additionally able to show in their own experiments that neural progenitor cells which have a known immunophenotype (in each case positive for CD15, CD56, CD90, CD133, CD164, CD172a, NGFR (neural growth factor receptor)) could be fractionated into subpopulations using the novel antibodies.
[0035] For the purposes of the present invention it is possible to use instead of the respective antibody mentioned also a fragment of the antibody without this being expressly mentioned in each case. “Fragment” means in this connection any fragment of an antibody retaining the antigen-binding function of the antibody. Examples of such fragments are Fab, F(ab′)2, Fv and other fragments such as CDR fragments. Said fragments display the binding specificity of the antibody and can also be produced for example by known methods.
[0036] The antibodies of the invention also make it possible now to produce further antibodies which bind to the same antigen. Through the antibodies of the invention it is possible to isolate the corresponding antigenic structure using generally known methods, and to develop further monoclonal antibodies against the same antigenic structure, known methods also being used in this case.
[0037] Another object of the present invention is a hybridoma cell line which has the ability to produce and release such antibodies, and in particular the hybridoma cell lines W8C3, W4A5 and 57D2.
[0038] The inventors have used the novel antibodies to produce for the first time monoclonal antibodies, and hybridoma cell lines producing and releasing them, which make specific recognition of neural stem cells possible. The antibodies thus represent a means which is unique to date for the physician and researcher on the one hand to detect such cells, and on the other hand where appropriate to manipulate these cells, either through the antibody itself or through reagents coupled thereto.
[0039] A further object of the present invention is a method for isolating and/or identifying neural stem cells, in which method there is use of an antibody or a fragment thereof which binds to the same antigen as an antibody produced by a hybridoma cell line which is selected from the group of the following hybridoma cell lines 57D2, W8C3 and W4A5 which were deposited on Aug. 14, 2002, at the DSMZ in accordance with the Budapest treaty under the numbers DSM ACC2571, DSM ACC2570 and DSM ACC2568.
[0040] The antibodies or fragments thereof particularly used in this connec-tion are those produced by a hybridoma cell line which is selected from the group of the following hybridoma cell lines 57D2, W8C3 and W4A5 which were deposited on Aug. 14, 2002 at the DSMZ in accordance with the Budapest treaty under the numbers DSM ACC2571, DMS ACC2570 and DSM ACC2568.
[0041] The inventors have realized that it is possible with the method of the invention in particular for neural progenitor cells to be identified and, for example, differ-entiated from mesenchymal stem cells.
[0042] Another object of the present invention is a method for identifying neural progenitor cells with an antibody, which method includes the following steps:
[0043] contacting a sample of a cell suspension which comprises neural progenitor cells to the novel monoclonal antibodies or fragments thereof, and
[0044] identifying those cells in the sample which bind to the novel mono-clonal antibodies or fragments thereof.
[0045] An additional object of the present invention is a method for isolat-ing neural progenitor cells with an antibody, comprising the following steps:
[0046] contacting a sample of a cell suspension which comprises neural progenitor cells to the novel monoclonal antibodies or fragments thereof, and
[0047] isolating from the sample those cells which bind to the novel mono-clonal antibody or to a fragment thereof.
[0048] The sample can be selected from any source which comprises neural stem cells, for example a sample from the bone marrow or peripheral blood. These cells are obtained by laboratory methods known in the art and are in many cases commercially available.
[0049] The contacting of a sample of a cell suspension which comprises neural stem cells can moreover take place in solution, as is the case for example on use of a flow cytometer (=fluorescent-activated cell sorter (FACS)).
[0050] In flow cytometry, cells are loaded with antibodies which are, on the one hand, specific for a surface marker and, on the other hand, coupled to a fluorescent dye. Cells which are marker-positive fluoresce, whereas the negative cells remain dark. It is thus possible to establish which portion of a cell population is marker-positive. At the same time, a flow cytometer allows the size and granularity of cells to be determined.
[0051] It is also possible to employ a method of magnetic cell separation (MACS, magnetic cell sorting). In this method, the cells are labeled with magnetic beads, it being possible for these beads to be coupled for example to the antibodies.
[0052] The contacting can also be carried out by immobilizing the mono-clonal antibody on a carrier as this is the case for example in column chromatography.
[0053] The cell suspension may be any solution with bone marrow cells, blood cells or tissue cells.
[0054] After the cell suspension has been mixed with the antibody, the cells which express the relevant antigen bind to the antibody, after which these cells can be identified and/or isolated from the cells which have not bound to an antibody by the described method.
[0055] The neural progenitor cells which have been identified/isolated in this way can then be employed for example for transplantation in order to achieve regeneration of neurological damage.
[0056] The invention relates further to the use of a novel antibody or of a fragment thereof for identifying neural progenitor cells.
[0057] The invention further relates to the use of the cell line TF 1 for pro-ducing antibodies or fragments thereof for isolating and/or identifying neural progenitor cells.
[0058] The invention additionally relates to the use of the cell line WERI-RB 1 for producing antibodies or fragments thereof for isolating and/or identifying of neural progenitor cells.
[0059] A further object of the present invention is a pharmaceutical compo-sition comprising one or more of the abovementioned antibodies of the invention.
[0060] Such a pharmaceutical composition may, besides the one or more antibodies, comprise further suitable substances such as, for example, diluents, solvents, stabilizers etc. These include for example physiological saline solutions, water, alcohols, and further suitable substances which are to be found for example in A. Kibble, “Hand-book of Pharmaceutical Excipients”, 3rd ed., 2000, American Pharmaceutical Association and Pharmaceutical Press.
[0061] An additional object of the present invention is a kit which comprises at least one of the novel antibodies.
[0062] Further advantages are evident from the appended figures and the description.
[0063] It will be appreciated that the features mentioned above and to be explained hereinafter can be used not only in the combination indicated in each case, but also alone or in other combinations, without leaving the scope of the present invention.
BRIEF DESCRIPTION OF THE FIGURE
[0064] Exemplary embodiments are depicted in the appended drawing and are explained in detail in the description. This shows:
[0065] FIG. 1 FACS analyses which show that neural progenitor cells ex-press CD15, CD56, CD90, CD133, CD164, CD172a;
DESCRIPTION OF PREFERRED EMBODIMENTS
Material and Methods
[0066] Neural progenitor cells were purchased from CellSystems, St. Katharinen, Germany.
[0067] The following monoclonal antibodies or antibody conjugates were employed for the fluorometric analyses: W8B2, W8C3, W4A5 and W7C5 (CD109), all of which were obtained starting from the retinoblastoma cell line WERI RB 1. This cell line is obtainable from the DSMZ under the number ACC90.
[0068] The monoclonal antibody 57D2 which was obtained by immunizing mice with the TF 1 erythroleukemia cell line (DSMZ: ACC334) were additionally em-ployed.
[0069] The antibodies of known specificities employed were CD10 PE, CD13 PE, CD34 PE, CD45 PE, CD56 PE, CD61 PE, CD117 PE (all obtainable from Becton Dickinson, Heidelberg, Germany). PE (phycoerythrin)-conjugated monoclonal antibodies with a specificity for CD90, CD140B and CD164 were obtained from PharMin-gen (San Diego, USA). The antibody against the nerve growth factor receptor (NGFR) was purchased from Sigma (Munich, Germany). CD133 PE (clone W6B3C1), CD167a (clone 48B3), CD172a PE (clone SE5A5), the CD15 specific antibody W6D3 and the CD105 specific monoclonal antibody 43A3 were produced in the inventor's laboratory. Unconjugated antibodies were stained using isotype-specific PE-conjugated goat anti-mouse antisera (Southern Biotechnology Associates, Inc., Birmingham, USA).
Staining of Cells and Flow Cytometry
[0070] For the cytometric analyses, the commercially available neural pro-genitor cells (NPC) were incubated with 10 μl of phycoerythrin-conjugated antibodies or 25 μl of culture supernatant in 96 well microtiter plates at 4° C. for 20 minutes. Unconju-gated monoclonal antibodies were stained after a washing step in FACS buffer (PBS; 0.5% BSA; 0.1% NaN3) using goat anti-mouse IgG1 PE (1:100) or goat anti-mouse IgG3 PE (1:20) antisera. After a further washing step, the cells were analyzed with a flow cytometer (FACSCalibur, Becton Dickinson) using the Cell Quest software (Bacton Dickinson).
[0071] For the immunocytochemical analysis of intracellular antigens and extracellular matrix proteins, the neural progenitor cells were fixed on 8 well chamber slides with acetone for 2 minutes and labeled with the primary antibody for 60 minutes. Staining was then carried out with Alexa 488 conjugated goat anti-mouse IgG or goat anti-rabbit IgG antisera. For the controls, the cells were labeled either with an isotype-matching control antibody or with a preimmune rabbit serum. The fluorescence of the cells was evaluated using a fluorescence microscope (Zeiss, Oberkochen, Germany).
Results
Immunophenotype of Neural Progenitor Cells
[0072] Commercially available fetal neural progenitor cells (NPC hereinaf-ter) (CellSystems, St. Katharinen, Germany) were investigated for their immunophenotype.
[0073] It was possible to detect two NPC populations differing in size in a double scatter plot. Large NPC showed stronger CD133, CD172a and W8C3 antigen expression than the smaller NPC, whereas CD13 was identified principally on a small NPC subpopulation. All NPC subpopulations expressed CD56, CD90, CD164, NGFR and the antigens to which the antibodies 57D2, W4A5, W6D3 (CD15) produced by the inventors bind. These cells were negative for CD45, CD105 (endoglin) and CD140b (PDGF RB), as well as for the antigens W7C5 (CD109) and W8B2.
[0074] FIG. 1 depicts selected examples of these analyses. It is unambigu-ously evident from histograms D and E in FIG. 1 that the NPC are positive for CD90 and CD56, while histograms I, J, K and L in FIG. 1 depict the positive results for W8C3, 57D2, W4A5 and W6D3 (CD15).
[0075] The extent to which the novel antibodies bind for example to mesen-chymal stem cells was investigated in other experiments. On the one hand, mesenchymal stem cells isolated by the inventors from bone marrow cells from the pelvic cavity of volunteer donors and, on the other hand, mesenchymal stem cells which can be purchased (CellSystems, St. Katharinen, Germany) were employed for this. In most cases, the expres-sion pattern of the commercial mesenchymal stem cells and that of the mesenchymal stem cells isolated by us (hereinafter: MSC) were identical or similar. The MSC proved to be unambiguously negative for W4A5, W6D3 and CD133 and only a small subpopulation of the MSC showed a weakly positive reaction for 57D2.
[0076] The results of the investigations are summarized in table 1 below, there having been investigation in this case of the antigen expression on commercially obtained neural progenitor cells (NPC, comm.) and that on mononuclear cells from the bone marrow of healthy donors (BMMNC).
[0077] The meanings in the table are − negative, i.e. no expression on the relevant cells, + positive, i.e. expression on the cells, (+) positive at least in one analysis, S slight to undetectable expression, P cell population <5%.
NPC Antigen/antibody comm. BMMNC CD13 P P CD34 S P CD45 − + CD56 + P CD90 + P CD105 − P CD117 S P CD133 + p CD140B − P CD164 + + CD167 S − CD172a + + W4A5 + − W6D3 (CD15) + + W7C5 (CD109) − P W8B2 − − W8C3 P − 57D2 + − NGFR + −
[0078] Comparing with BMMNC, therefore, NPC expressed the antigens of the novel antibodies W4A5, 57D2 and W8C3 and consisted mainly of a CD133 + population (25-40% compared with <1% BMMNC).
[0079] The growth of neurospheroids was observable on cultivation of the NPC in serum-free media in the presence of neural progenitor cell medium (CellSystems). In the presence of 10% fetal calf serum (FCS) and in the absence of growth factors, the spheres adhered to the plastic surface of the culture dishes. NPC cultivated in growth medium for astrocytes differentiated into astrocytes with long pseudopods. NPC kept on chamber slides in the presence of astrocyte medium expressed nestin, MAP2, neurofila-ments, GFAP, W4A5 and β2-chain laminin.
SUMMARY
[0080] Stem cells of the central nervous system such as neural progenitor cells represent in relation to therapeutic uses an important source for developing strategies for therapies to restore injured or diseased brain tissue. NPC can be isolated both from adult and from fetal brain. A large subpopulation of these cells is CD133 positive and negative for CD34, CD45 and CD24. In culture, these cells differentiate into neurospheres.
[0081] NPC has proved to be positive for CD56, CD90, CD133, W4A5, W6D3 (CD15), W8C3 and 57D2, and negative for CD45, CD10, W7C5 (CD109) and W8B2. Similar to the NPC expressed bone marrow subpopulations CD133, CD56, CD90 and CD15, it being rather improbable that these markers are also suitable as markers for NPC. The most promising markers are W4A5 and 57D2 which do not overall react with bone marrow populations. The antigens defined by the antibodies W4A5, 57D2 and W8C3 represent excellent surface markers with exceptional specificity for NPC. Since these are expressed in particular on mainly nestin-positive NPC, they are evidently expressed selectively on immature NPC. | The present invention relates to monoclonal antibodies or fragments thereof for isolating and/or identifying neural progenitor cells. The antibodies or fragments thereof bind to an identical antigen as an antibody which is produced by the hybridoma cell lines W4A5, W8C3 and 57D2 deposited on Aug. 14, 2002, at the under the numbers DSM ACC2571, DSM ACC2570 and DSM ACC2568. | 2 |
CROSS-REFERENCE OF RELATED APPLICATION
This application claims priority to U.S. Provisional Application No. 61/006,551 filed Jan. 18, 2008, the entire contents of which are hereby incorporated by reference, and is a U.S. national stage application under 35 U.S.C. §371 of PCT/US2009/031582 filed Jan. 21, 2009, the entire contents of which are incorporated herein by reference.
The invention was made with Government support of Grant No. DE-FG-06ER64249 awarded by the Department of Energy and Grant No. CA119347 awarded by the National Institutes of Health. The United States Government has certain rights in the invention.
BACKGROUND
1. Field of Invention
The current invention relates to microfluidic devices, and more particularly to microfluidic devices that include a droplet generator.
2. Discussion of Related Art
Thorough mixing is paramount for performing chemical or biochemical reactions to achieve high and repeatable yields. Rapid mixing improves desired reactions by avoiding side reactions caused by, for example, large excess of one reagent in uneven distribution. Speed of mixing may be particularly important in certain applications such as, for example, certain fast organic/inorganic syntheses or radiolabeling of imaging probes for positron emission tomography (PET) because of the short half-life time of the radioisotopes used.
Microfluidic chips typically manipulate fluid volumes in the range of nL (nanoliters) to μL (microliters). Mixing in these chips is challenging due to the absence of turbulence under most normal operating conditions due to low Reynold's number. As is well known in the art, the mixing rate is generally limited by diffusion. For example, if two streams enter a single channel at a Y-junction, the streams will flow side-by-side and, depending on flow rates and diffusion constants, a relatively long flow distance is needed before the streams are well-mixed by diffusion.
A vast range of mixing methods and chip designs have been reported in the literature (Nguyen, N-T, Wu, Z., Micromixers—a review, J. Micromech. Microeng. 15: R1-R16 2005; Hessel, V., Lowe, H., Schonfeld, F., Micromixers—a review on passive and active mixing principles, Chemical Engineering Science 60: 2479-2501, 2005). Passive and active means to “stretch and fold” the fluids to be mixed have been reported in which the diffusion distance is decreased and mixing by diffusion may occur more rapidly (Gunther, A., Jhunjhunwala, M., Thalmann, M., Schmidt, M. A., Jensen, K. F., Micromixing of miscible liquids in segmented gas-liquid flow, Langmuir 21(4): 1547-1555, 2005).
Droplet-based mixing may be the most efficient as measured in terms of time and on-chip space, in contrast to other forms of mixing that take much more time and on-chip space. One method of droplet-based mixing employs a continuous flow droplet-based approach (Gunther, A., Jhunjhunwala, M., Thalmann, M., Schmidt, M. A., Jensen, K. F., Micromixing of miscible liquids in segmented gas-liquid flow, Langmuir 21(4): 1547-1555 2005; Song, H., Chen, D. L., Ismagilov, R. F., Reactions in proplets in Microfluidic Channels, Angewandte Chemie 45: 7336-7356, 2006; Song, H., Bringer, M. R., Tice, J. D. Gerdts, C. J., Ismagilov, R. F., Experimental test of scaling of mixing by chaotic advection in droplets moving through microfluidic channels, Applied Physics Letters 83(22): 4664-4666, 2003; Song, H., Ismagilov, R. F., Millisecond kinetics on a microfluidic chip using nanoliters of reagents, J. Am. Chem. Soc. 125: 14613-14619, 2003). Droplets containing two or more reagents with desired ratios of volume are created by physical processes and flow along a microchannel. The flow process generates a chaotic mixing action within a droplet that may improve mixing length and time. For example, the Ismagilov group has observed sub-second mixing time in a dispersionless droplet mixing technology that they developed (Ismagilov, R. F., Experimental test of scaling of mixing by chaotic advection in droplets moving through microfluidic channels, Applied Physics Letters 83(22): 4664-4666, 2003; Song, H., Ismagilov, R. F., Millisecond kinetics on a microfluidic chip using nanoliters of reagents, J. Am. Chem. Soc. 125: 14613-14619, 2003). They found that the spatial distribution of liquids within a droplet is critical to the mixing efficiency in straight mixing channels. Specifically, a droplet that has end-to-end distribution mixes more efficiently than a droplet having a side-by-side distribution. The reason is that liquid flowing in a straight channel creates a recirculation within each half, side-by-side, in the droplet. A serpentine flow path may be needed for more efficient mixing of a droplet having a side-by-side distribution.
Although fast mixing may be achieved, the implementation is difficult for a number of applications, especially those using low volumes of at least one reagent. This is because it is hard to make the reagents that are being mixed arrive at the mixing junction exactly at the same time. Quite often, some droplets have to be discarded due to, for example, incorrect volume ratios. Incorrect ratios also can occur as droplet formation stabilizes in the first several minutes of operation, requiring the incorrectly formed droplets to be discarded. Furthermore, flow rates and other parameters must be laboriously tuned with care since operation depends on, for example, temperature, viscosity, type of solvents, number of reagents, desired volume ratios, etc. For example, Tice et al (Tice, J. D., Lyon, A. D., Ismagilov, R. F., Effects of viscosity on droplet formation and mixing in microfluidic channels, Analytica Chimica Acta 507: 73-77, 2004) observed viscosity to have an enormous impact on initial spatial distribution of reagents within each droplet, ranging from optimally good to the opposite for mixing in a straight channel. Variations in conditions over time can affect droplet uniformity. Generation of series of droplets having different sizes, volume ratios, etc. is especially difficult and many droplets must be discarded in the transition interval as operating parameters are altered.
In addition to the passive mixers that have been demonstrated in continuous flow microfluidic devices, active mixing has been demonstrated in integrated microfluidic chips. For example, the rotary mixer developed by Quake et al. (Chou, H-P, Unger, M. A., Quake, S. R. A microfabricated rotary pump, Biomedical Microdevices 3(4): 323-330, 2001; Hansen, C. L., Sommer, M. O. A., Quake, S. R., Systematic investigation of protein phase behavior with a microfluidic formulator, PNAS 101(40): 14431-14436, 2004) may be the most commonly used approach and has a simple fabrication process. The mixer, for example, may have one continuous closed path (e.g., a ring) around which fluids can be pumped. Due to extreme Taylor dispersion, the fluids become mixed after several cycles around the ring (Squires, T. M., Quake, S. R. Microfluidics: fluid physics on the nanoliter scale, Reviews of Modern Physics 77: 977-1026, 2005). The use of microvalves, in constrast to continuous flow microfluidic devices, can facilitate the manipulation of very small fluid volumes.
The rotary mixer and its variations, however, are not scalable designs. As the volume/length of the mixer increases, a longer time is required for circulating the fluids, and the effectiveness of pumping diminishes. For modest volumes (e.g., 1 μL), it can take several minutes to achieve thorough mixing. Furthermore, the rotary mixer and its variations are sensitive to the presence of bubbles, which may occur in a reaction resulting in the fluids being heated above the boiling point or the release of gas.
Therefore, there is a need for devices and methods for rapid and accurate mixing for integrated microfluidic devices.
SUMMARY
Some embodiments of the current invention provide a microfluidic mixer having a droplet generator and a droplet mixer in selective fluid connection with the droplet generator. The droplet generator comprises first and second fluid chambers that are structured to be filled with respective first and second fluids that can each be held in isolation for a selectable period of time. The first and second fluid chambers are further structured to be reconfigured into a single combined chamber to allow the first and second fluids in the first and second fluid chambers to come into fluid contact with each other in the combined chamber for a selectable period of time prior to being brought into the droplet mixer.
Some embodiments of the current invention provide a microfluidic droplet generator that has first and second fluid chambers structured to be filled with respective first and second fluids that can each be held in isolation for a selectable period of time. The first and second fluid chambers are further structured to be reconfigured into a single combined chamber to allow the first and second fluids in the first and second fluid chambers to come into fluid contact with each other in the combined chamber for a selectable period of time prior to said droplet generator being brought into fluid connection with a microfluidic device.
Some embodiments of the current invention may provide a method of mixing fluids that includes: filling a first microfluidic chamber with a first fluid and holding it in isolation for a first selectable period of time; filling a second microfluidic chamber with a second fluid and holding it in isolation for a second selectable period of time; providing a fluid connection between the first and second microfluidic chambers after the first and second selectable periods of time to allow the first and second fluids to come into fluid contact to form a droplet while said droplet remains otherwise in isolation for a third selectable period of time, and providing a fluid connection between the first and second microfluidic chambers and a droplet mixer to allow the droplet to flow into said droplet mixer.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objectives and advantages will become apparent from a consideration of the description, drawings, and examples.
FIG. 1A shows a diagrammatic illustration of a micromixer according to an embodiment of the current invention.
FIG. 1B shows a diagrammatic illustration of a droplet generator according to an embodiment of the current invention.
FIG. 2 shows a schematic illustration of a micromixer chip according to an embodiment of the current invention.
FIGS. 3A-3I illustrate an example of generating droplets according to an embodiment of the current invention.
FIGS. 4A-4I illustrate an example of generating droplets of variable mixing ratios according to an embodiment of the current invention.
FIG. 5 shows a schematic illustration of a degasser according to an embodiment of the current invention.
DETAILED DESCRIPTION
Some embodiments of the current invention are discussed in detail below. In describing embodiments, specific terminology is employed for the sake of clarity. However, the invention is not intended to be limited to the specific terminology so selected. A person skilled in the relevant art will recognize that other equivalent components can be employed and other methods developed without departing from the broad concepts of the current invention. All references cited herein are incorporated by reference as if each had been individually incorporated.
Herein the terms “microfluidic chip”, “microfluidic chip system”, “chip”, “microfluidic device” may be used interchangeably without significantly changing the context of the disclosure. Specifically, the “microfluidic chip system” refers to the microfluidic chip and other components going into and out of the chip, whereas “chip” and “microfluidic chip” both refer to the microfluidic chip alone. A “microfluidic device” refers to a device or component having microfluidic properties.
FIG. 1A shows a diagrammatic illustration of a micromixer 100 according to an embodiment of the current invention. Micromixer 100 includes a droplet generator 102 and a droplet mixer 104 . Droplet generator 102 may have chamber structures to generate, for example, one or more droplets. Droplet mixer 104 may have channel structures to mix, for example, the generated droplets. Droplet generator 102 is in fluid connection with droplet mixer, e.g., via structure 106 . Structure 106 may be a channel through which droplets can be transported.
FIG. 1B shows a diagrammatic illustration of a droplet generator 102 according to an embodiment of the current invention. Droplet generator 102 may include a first chamber 108 and a second chamber 110 . Structure 112 may separate first chamber 108 and second chamber 110 . Structure 112 may be lifted or otherwise moved to allow chambers 108 and 110 to become a single combined chamber. Structure 112 may be, for example, a valve.
FIG. 2 shows a schematic illustration of a micromixer chip 200 according to an embodiment of the current invention. Droplet generator 207 may include fluid chambers 108 and 110 . Inlets 201 and 202 may feed fluid chambers 108 and 110 , respectively. Vacuum ports 203 and 204 may serve fluid chambers 108 and 110 , respectively. Droplet mixer 104 may include serpentine channel 213 . Degasser 210 may be served by vacuum port 208 . Outlet 209 may be an exit for droplets produced by micromixer chip 200 . Outlet 209 may further interface to other microfluidic devices.
Reagent A may enter fluid chamber 108 via inlet 201 and reagent B may enter fluid chamber 110 via inlet 202 . Fluid chambers 108 and 110 may be configured to become one combined chamber after being filled with reagents A and B for certain periods of time. The droplet generated by the combined chamber may be pushed to serpentine channel 213 via, for example, coordinated applications of high-pressure air through gas inlet 205 . In degasser 210 , vacuum may be applied through vacuum port 208 to remove gas within and between generated droplets. For example, due to a pressure drop across a thin membrane between serpentine channel 213 and the channels connected to vacuum port 208 of degasses 210 , gas may pass through the thin membrane into the channels connected to vacuum port 208 . After flowing through serpentine channel 213 , generated droplets of desired mixing ratio(s) may exit via outlet 209 .
The design of droplet generator 102 may allow great flexibility and may enable us to achieve mixing in a distance shorter than that of conventional droplet mixers reported in the literature. The shorter distance associated with mixing may allow us to further reduce the mixing time and to reduce on-chip space used.
In addition, a narrow channel may be placed between fluid chambers 108 and 110 , such that a “jet” from fluid chamber 108 flows into fluid chamber 110 and pre-mixes the droplet so a portion of the circulating flow is substantially complete before the droplet has had a chance to move very far. The “jet” effect can also be created by air bubbles between the two fluid chambers. We have observed an air bubble to suddenly shift to one side of the microchannel leaving a narrow jet of liquid to flow between the channel wall and the bubble. This bubble actually serves a temporary induction role in the “jet” formation.
Very large droplets may also be made according to some embodiments of the current invention. We have observed in our experiments large droplets that were mixed very well, and this can increase the throughput (e.g., volume mixed per time) of the mixer. Large droplets (e.g., hundreds of nanoliters in volume) are difficult to make stably in a continuous flow chip, and the controllable range of droplet sizes is quite limited. For example, only about one order of magnitude difference in size could be achieved in the literature (Song, H., Ismagilov, R. F., Millisecond kinetics on a microfluidic chip using nanoliters of reagents, J. Am. Chem. Soc. 125: 14613-14619, 2003).
The examples use air which may be removed between the sequence of droplets after mixing by pulling vacuum through a thin membrane between two channels of the chip. One could use other methods of removing gas from the channels, including liquid/gas separators according to other embodiments of the current invention. For example, these separators may include fine channels/porous membrane through which liquid passes but not gas in some embodiments of the current invention.
For the conservation of on-chip space, degasser 210 may begin functioning while the droplets are still being mixed. Care should be taken such that the generated droplets remain separated until each droplet is fully mixed, or mixing may not be completed.
In general, the micromixer chip 200 may be made of such materials as silicon, glass, polymer, epoxy-polymer, poly-dimethylsiloxane (PDMS), perfluoropolyether (PFPE) etc. In some embodiments, variation in at least one dimension of microfabricated structures is controlled to the micron level, with at least one dimension being microscopic (i.e. below 1000 μm). Microfabrication can involve semiconductor or microelectrical-mechanical systems (MEMS) fabrication techniques such as photolithography and spin coating that are designed to produce feature dimensions on the microscopic level, with at least some of the dimensions of the microfabricated structure requiring a microscope to reasonably resolve/image the structure. Examples of fabrication of microfluidic chips in the art include, U.S. Pat. No. 7,040,338, and U.S. patent application Ser. Nos. 11/297,651; 11/514,396, and 11/701,917. Materials and methods disclosed in these references are applicable for the fabrication of some embodiments of the current invention.
Some embodiments of the current invention may provide a way to inexpensively and accurately generate droplets of different mixing ratios by filling fixed volume reservoirs on the chip. No specialized hardware is required, such as expensive syringe pumps or other types of complex on-chip or off-chip metering pumps.
FIG. 3A-3I illustrate a process of generating droplets according to an embodiment of the current invention.
FIG. 3A shows a schematic view of a droplet generator that can correspond to droplet generator 102 according to an embodiment of the current invention. The droplet generator 102 has two fluid chambers located along microchannel 300 . A first fluid chamber 108 is surrounded by valves 303 , 304 , 305 , and 308 . Inlet 201 is a port through which a reagent may be loaded into first fluid chamber 108 . Gas inlet 205 is a port through which gas may be allowed to enter microchannel 300 . Vacuum port 203 may connect to a vacuum pump. A second fluid chamber 110 is surrounded by valves 305 , 306 , 307 , and 309 . Valve 305 may connect the first fluid chamber 108 with the second fluid chamber 110 . Inlet 202 is a port through which a reagent may be loaded into the second fluid chamber 110 . Vacuum port 204 is a port that may connect to a vacuum pump.
FIG. 3B shows an example of one step during operation of the droplet generator 102 . Inlet 201 is prefilled with reagent A and inlet 202 is prefilled with reagent B. To start the mixer, it is noted that the input reagents must be connected to micromixer chip 200 . Further, it is noted that the principle of dead-end-filling may be used to ensure the reagents displace substantially all air in inlets 201 and 202 such that reagent A and reagent B are touching one side of valve 304 and 306 , respectively.
FIG. 3C shows an example of a subsequent step during operation of the droplet generator 102 . Valves 308 and 309 may be opened and a vacuum may be applied through vacuum ports 203 and 204 to the droplet generator 102 to remove substantially all air in the fluid chambers 108 and 110 .
FIG. 3D shows an example of a subsequent step during operation of the droplet generator 102 . Valves 308 and 309 may be closed to maintain the vacuum inside the fluid chambers 108 and 110 .
FIG. 3E shows an example of a subsequent step during operation of the droplet generator 102 . Valves 304 and 306 are opened and reagents A and B rush in (assisted by the negative pressure provided by the vacuum) to their respective fluid chambers 108 and 110 until full.
FIG. 3F shows an example of a subsequent step during operation of the droplet generator 102 . Valves 304 and 306 are closed to trap reagents A and B in the respective fluid chambers 108 and 110 . A precise volume of each reagent is thus measured and trapped, and no tuning of parameters is required to achieve the exact droplet size and mixing proportions that are desired.
FIG. 3G shows an example of a subsequent step during operation of the droplet generator 102 . Valve 305 between fluid chambers 108 and 110 is opened, so that the first fluid chamber 108 holding reagent A and the second fluid chamber 110 holding reagent B become one single combined chamber and the contents of reagents A and B merge together, forming a single droplet that has reagent A at one end and reagent B at the other.
FIG. 3H shows an example of a subsequent step during operation of the droplet generator 102 . Valves 303 and 307 are opened, and gas (e.g., air, nitrogen/argon if reactions are sensitive to air or moisture, etc.) is admitted from gas inlet 205 to push the formed droplet out of the filling region along microchannel 300 .
In the above example of dead-end filling at the inlets, gas is used. It is noted that an immiscible fluid, such as a liquid that can later be removed, may be used for the same purpose. The immiscible fluid may be later removed, e.g. by a selectively permeable membrane.
FIG. 3I shows an example of a subsequent step during operation of the droplet generator. Once the formed droplet is pushed outside the fluid chambers 108 and 110 , the valves 303 , 305 , and 307 are closed and the droplet generation cycle may repeat. Meanwhile, the gas pressure trapped between the formed droplet and valve 307 of the droplet generator may continue to push the formed droplet further into the mixing channel.
It is noted that the valves 304 and 306 perform a “latching” mechanism whereby the reagents can be “synchronized,” in a manner similar to electric charges in a digital integrated circuit (IC). Latching may ensure even the first droplet has the correct composition of liquids. It is noted that, for the same objective, latching may also be used in conjunction with a mechanism of automatic purging of reagent lines (see, for example, U.S. Patent Application No.: 2008/0131327, “System and method for interfacing with a microfluidic chip”).
A further advantage of having valves on the micromixer chip 200 can be the ability to stop the droplet flow so it can be analyzed with (inexpensive) low-speed, low-sensitivity cameras etc. according to some embodiments of the current invention. Continuous flow approaches require high-speed photography or averaging techniques to analyze droplet based mixing in a quantitative fashion. The valves also allow very simple integration to other microfluidic chip components, or to external fluid handling systems for automation.
Some embodiments of the current invention can provide an improved way to perform mixing when at least one participating reagent involves a tiny volume (e.g., 10 nL) or the reagents being mixed have disparate properties such as viscosity, surface tension, hydrophobicity/hydrophilicity, etc.
Droplet generation in existing continuous flow devices is difficult and is achieved by carefully tuned flow rates of (or pressures driving) the inlet fluids and carrier/separator stream, as well as properties of these fluids. Many parameters are inter-related, and it is impossible to change one parameter without affecting many others. As a result, it is difficult to independently control the desired droplet sizes and mixing ratios within the droplet without substantial additional experimentation and characterization of the system (e.g., laborious modeling). In addition, when using different total volumes of the two starting liquids, there can be different total fluidic resistances from the liquid inlet to the mixing microchannel, further complicating the establishment and maintenance of a stable droplet flow. It is noted that different volumes can occur in automated systems, e.g., when mixing a number of different precious samples with a bulk reagent/solvent of larger volume.
In practical systems, droplet generation is further complicated when using liquids of different viscosities, surface tension, hydrophobicity/hydrophilicity or other physical parameters. All of these factors can have a significant impact on ultimate droplet size and the ratio of reagent A to reagent B for each droplet in actuality. Although it is possible to tune the droplet generator for one set of parameters, it can be difficult to switch from one reagent to another without changing many parameters. Thus, when changing reagent, the droplet generator may no longer be appropriately tuned.
Furthermore, in existing devices, a significant number of droplets may need to be “discarded” before a stable droplet flow is established. That is, it is very hard to start effective mixing at the very first droplet. This can waste considerable amount of valuable reagents, and it may be difficult in an automated system to determine both when the steady state has been achieved, and which droplets to discard. Reagent waste also occurs in all of the known “injection” schemes developed so far in elastomeric valve-containing microfluidic chips.
In contrast, by “latching” the fluid flow during filling of the mixing reservoirs, the need for a parameter tuning phase at startup can be eliminated and accurate mixing can begin with the first droplet. Consequently, a droplet can be accurately and efficiently generated in a predictable manner. By loading both liquids right up to the inlet and holding them with valves, we can ensure that even the very first droplet can be accurately mixed at the correct ratio of liquids. Because we are filling a chamber of well-defined volume, we can get a precise 1:1 (or any desired) ratio for every single droplet. The filling is achieved with valves that act independently of fluid properties such as viscosity, solvent composition, surface-tension, etc. We may also mix two gases between liquid plugs (like oil or water plugs if two gases are not water-miscible). Thus it is easy to switch to different fluids.
Furthermore, inlet liquids can be driven by pressure in an automated system, a much cheaper and more flexible approach than volume flow-rate-controlled flow. Additionally, droplets can be generated in an end-to-end fashion and can be mixed in a straight channel. No wavy channel is needed and thus fabrication is simpler in some embodiments of the current invention.
It should be noted that the volume of droplets and mixing ratio of reagents may be controlled at the level of the chip design, by fabricating fluid chambers with the desired volumes and proportions. Variable mixing ratio can also be achieved by partitioning one or both chambers with extra valves so that various portions of the chamber(s) can be selectively opened when generating a particular droplet. For example, we can design a chip wherein one unit portion of reagent A may be mixed with 1, 2, 3, 4, 5, or even more unit portions of reagent B. The chip design can be further generalized to accommodate a programmable variation of two orders of magnitude in a chip of practical size. This feature may be very useful, for example, for automated generation of series dilutions for optimizing reaction conditions and parameters.
FIGS. 4A-4I illustrate an example of generating droplets with variable mixing ratios according to an embodiment of the current invention.
FIG. 4A shows a schematic view of a droplet generator that could correspond to droplet generator 102 that is capable of variable mixing ratios according to an embodiment of the current invention. The droplet generator 102 has two fluid chambers located along microchannel 300 . The first fluid chamber 108 is surrounded by valves 303 , 304 , 305 , and 308 . Inlet 201 is a port through which a reagent may be loaded into the first chamber 108 . Gas inlet 205 is a port through which gas may be allowed to enter microchannel 300 . Vacuum port 203 is a port that may connect to a vacuum pump. The second fluid chamber 110 may be surrounded by valves 305 , 306 , 403 , and 309 . The second fluid chamber 110 can further utilize valves 307 , 401 , 402 , and 404 . Valve 305 may connect the first fluid chamber 108 with the second fluid chamber 110 . Inlet 202 is a port through which a reagent may be loaded into the second fluid chamber 110 . Vacuum port 204 is a port that may connect to a vacuum pump. In this configuration, mixing ratios of 1:1, 1:2, 1:3, 1:4, and 1:5 can be realized and a ratio of 1:4 is illustrated as an example in which valves 307 , 401 , and 402 are open.
FIG. 4B shows an example of one step during operation of the droplet generator 102 . Inlet 201 is prefilled with reagent A and inlet 202 is prefilled with reagent B. To start the mixer, it is noted that the input reagents must be connected to micromixer chip 200 . Further, it is noted that the principle of end-filling may be used to ensure the reagents displace substantially all air in inlets 201 and 202 such that reagent A and reagent B are touching one side of valve 304 and 306 , respectively.
FIG. 4C shows an example of a subsequent step during operation of the droplet generator 102 . Valves 308 and 309 may be opened and vacuum may be applied to the droplet generator 102 to remove substantially all air in the fluid chambers 108 and 110 .
FIG. 4D shows an example of a subsequent step during operation of the droplet generator 102 . Valves 308 and 309 may be closed to maintain the vacuum inside the fluid chambers.
FIG. 4E shows an example of a subsequent step during operation of the droplet generator 102 . Valves 304 and 306 are opened and reagents A and B rush in (assisted by the negative pressure provided by the vacuum step) to their respective fluid chambers 108 and 110 until full.
FIG. 4F shows an example of a subsequent step during operation of the droplet generator 102 . Valves 304 and 306 are closed to trap reagents A and B in the respective fluid chambers. A precise volume of each reagent is thus measured and trapped, and no tuning of parameters is required to achieve the precise droplet size and mixing proportions that are desired.
FIG. 4G shows an example of a subsequent step during operation of the droplet generator 102 . Valve 305 between fluid chambers 108 and 110 is opened, so that the first fluid chamber 108 holding reagent A and the second fluid chamber 110 hold reagent B become one single combined chamber and the contents of reagents A and B merge together, forming a single droplet that has reagent A at one end and reagent B at the other, with a desired mixing ratio of 1:4.
FIG. 4H shows an example of a subsequent step during operation of the droplet generator 102 . Valves 303 , 403 , and 404 are opened, and gas (e.g., air, nitrogen/argon if reactions are sensitive to air or moisture, etc.) is admitted from gas inlet 205 to push the formed droplet out of the filling region along microchannel 300 .
FIG. 4I shows an example of a subsequent step during operation of the droplet generator 102 . Once the formed droplet is pushed outside the fluid chambers 108 and 110 , the valves 303 , 305 , and 403 are closed and the droplet generation cycle may be repeated. Meanwhile, the gas pressure trapped between the formed droplet and valve 404 of the droplet generator 102 may continue to push the formed droplet further into the mixing channel.
Unlike precisely tuned droplet generators that can mix volumes of one pre-determined ratio or alternate between two or more different mixing ratios, some embodiments of the current invention enables flexible and broad control over the mixing ratio and may even allow changing the mixing ratio on the fly from one droplet to the next. Changing the mixing ratio on the fly is very useful for automation of reaction condition optimization and other high-throughput screening applications. Changing the mixing ratio can be done reliably and predictably, even on the very first attempt, and does not require a special tuning procedure to arrive at a steady state sequence of droplets having the desired mixing ratio.
Mixing of three or more reagents may also be realized in a straightforward manner according to some embodiments of the current invention. We can simply add a third fluid chamber in series with the two in the above examples. If desired, this could be generalized to a large number of reagents. Some inlets could be used for cleaning solutions; for example, the mixing chamber could be cleaned between each droplet, or a set of droplets. The straightforwardness and predictability of mixing multiple solutions is in stark contrast to continuous flow droplet generators. For example, Srisa-Art et al. (Srisa-Art, M., deMello, A. J., Edel, J. B., High-throughput DNA droplet assay using picoliter reactor volumes, Anal. Chem. 79: 6682-6689, 2007) mixed three solutions to produce droplets with varying fluorophore concentration. However, in this reference, to achieve various concentrations, simultaneous tuning of several volume flow rates was required.
Other capabilities associated with continuous flow droplet generators may also be realized with some embodiments of the current invention. For example, generation of droplets of alternating composition could be achieved at the programmatic level, i.e. by filling one chamber, pushing it out of droplet generator, filling a different chamber, pushing it out, and alternating back and forth.
One way of adjusting the mixing ratio is to adjust the reagent driving pressure under fixed filling time, or using variable filling time, such that fluid chambers 108 and 110 are filled to essentially the desired extents. This approach may make the droplet generator a little more dependent on fluid properties, but can give a finer degree of control over ratio.
Because the droplets are generated in an end-to-end fashion, a straight channel is sufficient to give effective mixing over a very short distance according to some embodiments of the current invention. Thus, the mixing channel may simply include a straight channel in some embodiments of the current invention. Bends in the path can be added to provide some mixing across the long axis of the droplet to account for any asymmetries in the initial droplet generation in other embodiments of the current invention. In other embodiments, grooves or other structures can be included in the mixing channel to induce chaotic advection in the flow.
Depending on the microfluidic technology and application, bubbles are often undesirable in microfluidic systems. A gas extractor, e.g., a degasser 210 , may be needed to remove the gas bubbles that exist in the liquid stream, and to reconstitute the series of bubbles as a continuous plug of fluid. The degasser 210 can also remove gas-containing bubbles that are generated by a reaction after mixing. The degasser 210 may further remove gas pockets between a sequence of droplets.
The degasser 210 may ensure that no gas enters the next step/process of a microfluidic chip, e.g. a chemical reactor. The degasser 210 may have a long pathway for droplets to flow, with an adjacent (e.g., in a lower layer of the chip, separated by a thin, e.g., 20 μm, layer of polymer) channel to which vacuum is applied.
FIG. 5 shows a schematic illustration of a degasser 210 according to an embodiment of the current invention. Droplets 503 flow in a horizontal serpentine channel 213 (serpentine to pack a long length into small chip area). Vacuum is applied from vacuum channel 502 below, orientated perpendicularly. At each crossing of serpentine channel 213 and vacuum channel 502 , air is pumped out of the serpentine channel 213 due to the pressure drop across the thin gas-permeable membrane separating a droplet 503 and vacuum channel 502 , and the spacing between droplets 503 decreases. By judicious choices of the pressure of injected air, time duration of air injection, and length of serpentine channel 213 , substantially complete removal of air is possible. It is noted that if the vacuum channel 502 is directly below the serpentine channel 213 and is allowed to follow along the same path, it would simply collapse and thus become ineffective. The perpendicular orientation reduces the surface area of the permeable membrane through which the applied vacuum is acting, but provides structural integrity of the channel.
We describe, as one example, the use of air to separate droplets to facilitate mixing. In other embodiments, an immiscible fluid can be used such as a liquid that can later be removed, e.g. by a selectively permeable membrane. Therefore, all such variations are intended to be within the scope of the current invention.
The droplet generator component and overall system according to an embodiment of the current invention may provide a way to programmatically mix reagents in different mixing ratios, which is useful in several applications such as, for example, generating a dilution series to optimize reaction conditions for labeling of biological molecules or organic compounds with radioisotopes or fluorophores, etc. The mixing ratio can even be changed on the fly, i.e., from one droplet to the next, if desired. Such flexibility is not afforded by existing approaches in which the mixing ratio is built into the chip design and the various variables (e.g., flow rate, reaction time, etc.) that impact the mixing process are interdependent and cannot be independently set.
Some aspects of the invention can facilitate the integration of two different types of microfluidic devices, i.e. digital integrated microfluidic devices, and droplet-based continuous flow systems. The droplet generator 102 and degasser 210 can be used in bridging these types of systems. One application taking advantage of the hybrid approach is chemical synthesis in small batches, such as to produce radiolabeled probes for positron emission tomography (PET) imaging. Batch-mode synthesis requires integrated microfluidic valves to manipulate the small volumes of liquid and keep the liquid trapped during reaction steps that are heated. The digital integrated microfluidic platform currently offers only a rotary mixer as an integrated mixing solution for small volumes of liquid; unfortunately this rotary mixer can be rather slow in certain volume regimes e.g., hundreds of nL to several μL or more) and thus is not suitable for processes involving short-lived radioisotopes because substantial radioactive decay can occur during the prolonged mixing steps. Some embodiments of the current invention make it possible to integrate fast droplet-based mixers with what is traditionally considered the continuous-flow device domain.
This mixing chip according to an embodiment of the current invention can be used as a component of a microfluidic chip, or can be integrated with an external microfluidic system when a desired process must be carried out with small volumes and/or very rapid mixing. For example, by building an interface between a semi-automated chemical synthesis unit and the mixing chip, one may obtain a system wherein the synthesis unit prepares a radiolabeled molecule while the mixing chip automatically mixes a tiny volume of this radiolabeled molecule (a radiolabeling tag or prosthetic group) with a biological molecule to facilitate a biological labeling reaction.
We believe the micromixer design according to an embodiment of the current invention is extremely flexible, and it is a natural fit to “digital” integrated microfluidic devices (i.e., chips that use valves to control the flow of fluids). It can solve many problems of current mixer setups and help to ensure that droplet mixing is accurate on even the first drop because there is no tuning procedure, and the filling may not have to rely on the contents of the downstream channel and back-pressure that this channel generates. There is essentially no waste of material in filling, e.g., a flow-through injector element. Furthermore, many droplet parameters (e.g., size, composition, etc.) may be tuned separately, without having to consider the links between flow rates, concentrations, speed, droplet size, etc. that plague existing approaches. The mixer design therefore enables a wide variety (different solvent, viscosity, surface tension, hydrophilicity/hydrophobicity, etc) of fluids to be mixed at different mixing ratio, and even allows mixing of three or more individual solutions. For these reasons, our mixer design according to an embodiment of the current invention is particularly suited for automated microfluidic applications.
The micromixer according to an embodiment of the current invention is suitable for integration into other application-specific chips and may have applications in, but not limited to: fluorophore labeling of precious primary antibodies; radiolabeling of nanoparticles, small molecules, biomolecules for micro-PET/PET imaging; radiolabeling for in vivo biodistribution studies or in vitro cell assays; fast chemical reactions; fast biological reactions (for example, enzymatic reactions); organic synthesis (conventional); synthesis of mono dispersion of nanoparticles; drug screening; performing conventional enzyme-linked immunosorbent assay (ELISA) in a continuous-flow fashion; mixing different portions of reagents (controlled concentration); screening reaction condition and reagent equivalent; droplet single cell analysis of DNA hybridization using SYBRT™-green; and automatic matrix assisted laser desorption/ionization mass spectrometer (MALDI-MS) spotting.
For example, making fluorescence-labeled antibodies to directly visualize antigens for applications such as, e.g. ELISA, cell immunostaining, and fluorescent-activated cell sorting (FACS), etc., can be a time-consuming, tedious, and expensive process. For labeling experiments, the optimal ratio between labeling motif and biological molecule often has to be determined by trial and error. During such processes, a considerable amount of precious biomaterial is inevitably wasted. An integrated micromixer system according to an embodiment of the current invention can provide a simple automated method to generate the required data for optimizing the ratio of fluorophore-antibody labeling using only a minute amount of sample.
In using 18 F-labeled prosthetic groups, such as N-succinimidyl-4-[ 18 F]fluor benzoate ([ 18 F]SFB), to label nanoparticles, small molecules, and biomolecules for micro-PET/PET imaging, there is a need to perform such a routine process automatically just prior to imaging to reduce operator exposure to radiation, improve repeatability, and avoid radioactive decay of precious, short-lived labeled probes, etc. Examples of small molecules and bio-molecules may include, but are not limited: intact monoclonal antibodies (such as, Herceptin, Cetuximab, Bevacizumab, etc.) and their engineered fragments, small high-affinity protein scaffolds (such as, affibodies), small interfering ribonucleic acids (siRNAs), deoxyribonucleic acids (DNAs), peptide nucleic acids (PNAs), locked nucleic acids (LNAs) and their derivatives, mono-/oligo-saccharides and glycoproteins, and various peptides and analogs, etc. An integrated micromixer/radiochemistry microfluidic chip could achieve this. In the case of preparation of [ 18 F]SFB probes, the micromixer may perform the entire reaction if the whole chip is heated to the modest temperatures required.
Some embodiments of the current invention may be applied in 64 Cu-DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) and 124 I-labeling of nanoparticles, small molecules, and biological molecules for micro-PET imaging, receptor binding studies, biodistribution studies, metabolism studies, or cell assays. Examples of molecules may include, but are not limited to: intact monoclonal antibodies (such as, Herceptin, Cetuximab, Bevacizumab, etc.) and their engineered fragments, small high-affinity protein scaffolds (such as, affibodies), small interfering ribonucleic acids (siRNAs), deoxyribonucleic acids (DNAs), peptide nucleic acids (PNAs), locked nucleic acids (LNAs) and their derivatives, mono-/oligo-saccharides and glycoproteins, and various peptides and analogs, etc.
Some embodiments of the current invention may be used in conventional organic synthesis processes by efficient mixing of reacting reagents with subsequent reactions somewhere on or off chip.
Further, in synthesizing mono-dispersed nanoparticles (e.g., Au, Ag, SiO 2 , CdCl 2 , CdS, CdSe, etc.), some embodiments of the current invention may be applied to achieve mixing of precise volumes of inorganic precursors.
Some embodiments of the current invention may be applied in fast chemical reaction. For example, each droplet actually is a snap shot of an instant during a reaction process in both space and time. By looking at droplets at different distances along the flow, a reaction process can be monitored and studied in detail. One example application, not intended to limit the scope of the embodiment, is the study of biocatalytic reactions involving multiple enzymes.
Some embodiments of the current invention may be applied in drug screening experiments using cells in-vitro, for example, in mixing different portions or combinations of drugs. In addition to drugs, the effects additional molecules such as growth factors, ligands, or antibodies and their engineered fragments, short peptides and analogs, etc., and their combinations, may be studied.
In another example of droplet-based cell analysis of deoxyribonucleic acid (DNA) hybridization using SYBRT™-green, some embodiments of the current invention may be used in virus detection and messenger ribonucleic acid (mRNA) expression analysis. Virus detection may involve applying direct lysis of sample, denaturing and cleaning out double strands of DNA, applying primer pairs, and performing polymerase chain reaction (PCR) or real-time polymerase chain reaction (RT-PCR), applying fluorescent dye (sensitive for double strand only), and performing fluorescence read-out. mRNA expression analysis may take the steps of applying direct lysis of sample; denaturing and cleaning out double strands of DNA; applying primer pairs; performing RT-PCR; applying fluorescence dye (for double strand only); and performing fluorescence read-out.
In automatic matrix assisted laser desorption/ionization mass spectrometer (MALDI-MS) spotter, the droplet mixer according to an embodiment of the current invention can mix samples with matrix solution very effectively before spotting on the MALDI-MS sample loading plate. It may be desirable that the chip be disposable to avoid sample contamination.
To increase the rate of droplet generation and the total throughput, one technique is to use several droplet generators in parallel with the outlets combined into a single channel on one single microfluidic chip. For each cycle, all N droplet generators inject a droplet in rapid succession into the common channel.
In describing embodiments of the invention, specific terminology is employed for the sake of clarity. However, the invention is not intended to be limited to the specific terminology so selected. The above-described embodiments of the invention may be modified or varied, without departing from the invention, as appreciated by those skilled in the art in light of the above teachings. It is therefore to be understood that, within the scope of the claims and their equivalents, the invention may be practiced otherwise than as specifically described. | The invention may provide a microfluidic mixer having a droplet generator and a droplet mixer in selective fluid connection with the droplet generator. The droplet generator comprises first and second fluid chambers that are structured to be filled with respective first and second fluids that can each be held in isolation for a selectable period of time. The first and second fluid chambers are further structured to be reconfigured into a single combined chamber to allow the first and second fluids in the first and second fluid chambers to come into fluid contact with each other in the combined chamber for a selectable period of time prior to being brought into the droplet mixer. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This patent application is a non-provisional patent application of U.S. provisional patent application 61/698,923 filed on Sep. 10, 2012 and entitled “Method of Converting Methane to Methanol” the content of each of which is hereby incorporated by reference in its entirety.
STATEMENT OF FEDERALLY FUNDED RESEARCH
None.
INCORPORATION-BY-REFERENCE OF MATERIALS FILED ON COMPACT DISC
None.
TECHNICAL FIELD OF THE INVENTION
The present invention relates generally to compositions and methods for the synthesis of methanol and in particular, to compositions and methods for the synthesis of methanol involving a cycle which includes the photocatalytic conversion of methane.
The present invention relates to an improvement in processes designed to produce methyl alcohol from natural gas using chlorination technology. The improvement permits the use of natural gas containing significant levels of inert gases while achieving high methane efficiencies. The process encompasses the use of multiple thermal chlorination reactors, each with a natural gas recycle loop. These reactors are arranged in a cross-flow reactor system whereby the gas purge from the first thermal reactor is fed to the second, and so on until the last thermal reactor, which is vented to the atmosphere.
BACKGROUND OF THE INVENTION
Without limiting the scope of the invention, its background is described in connection with the photocatalytic conversion of methane to methanol. Methane, a major component of natural gas, is an abundant material world-wide; however, it is difficult and costly to transport as a gas. The conversion of methane to a more easily transported source (e.g., methanol) is important in many industries including the oil and gas industry. In addition, methanol is a key building block to many valuable chemical products. Production of alcohols by oxidation has been difficult because the oxidation reaction tends to completion to carbon dioxide and over-oxidation is a persistent problem. Therefore, conventional approaches to synthesize methanol from methane generally have poor conversion efficiencies, slow reaction rates, and requires abundant energy sources, making them impractical.
For example, U.S. Pat. No. 8,211,825, entitled, “Methanol Oxidation Catalyst,” discloses a methanol oxidation catalyst comprising a material of composition: PtxMzTau in which Pt is platinum, Ta is tantalum, M is an element which comprises at least one selected from the group consisting of V (vanadium), W (tungsten), Ni (nickel) and Mo (molybdenum), x is 40 to 98%, z is 1.5 to 55%, and u is 0.5 to 40%. To maximize catalytic activity the material is preferably in the form of nanoparticles. The values of x, z, and u are selected such that the element exhibits X-ray photoelectron spectroscopy peaks derived from an oxygen bond and a metal bond in which a peak area derived from the oxygen bond is twice or less the peak area derived from the metal bond.
For example, U.S. Pat. No. 8,173,851, entitled, “Processes for Converting Gaseous Alkanes to Liquid Hydrocarbons,” discloses a process for converting gaseous alkanes to olefins, higher molecular weight hydrocarbons or mixtures thereof wherein a gaseous feed containing alkanes is thermally reacted with a dry bromine vapor to form alkyl bromides and hydrogen bromide. Poly-brominated alkanes present in the alkyl bromides are further reacted with methane over a suitable catalyst to form monobrominated species. The mixture of alkyl bromides and hydrogen bromide is then reacted over a suitable catalyst at a temperature sufficient to form olefins, higher molecular weight hydrocarbons or mixtures thereof and hydrogen bromide. Various methods are disclosed to remove the hydrogen bromide from the higher molecular weight hydrocarbons, to generate bromine from the hydrogen bromide for use in the process, and to selectively form mono-brominated alkanes in the bromination step.
For example, U.S. Pat. No. 6,156,211, entitled, “Enhanced Photocatalytic Conversion of Methane to Methanol Using a Porous Semiconductor Membrane,” discloses a method and apparatus for the conversion of methane in solution or gas which provides a photochemical conversion in a unique two-phase boundary system formed in each pore of a semiconductor membrane in a photocatalytic reactor. In a three-phase system, gaseous oxidant, methane contained in a liquid, and solid semiconductor photocatalyst having a metal catalyst disposed thereon, meet and engage in an efficient conversion reaction. The porous membrane has pores which have a region wherein the meniscus of the liquid varies from the molecular diameter of water to that of a capillary tube resulting in a diffusion layer that is several orders of magnitude smaller than the closest known reactors.
For example, U.S. Pat. No. 5,720,858, entitled, “Method for the Photocatalytic Conversion of Methane,” discloses a method for converting methane to methanol which involves subjecting the methane to visible light in the presence of a catalyst and an electron transfer agent. Another embodiment of the invention provides for a method for reacting methane and water to produce methanol and hydrogen comprising preparing a fluid containing methane, an electron transfer agent and a photolysis catalyst, and subjecting said fluid to visible light for an effective period of time.
For example, U.S. Pat. No. 6,137,017, entitled, “Methanol Process for Natural Gas Conversion,” discloses a process for producing methyl alcohol from natural gas using chlorination technology. The process includes reacting methyl chloride, hydrogen chloride, oxygen and perchloroethylene in a catalytic reactor to give methanol product and hexachloroethane and using the C 2 C 16 to chlorinate methane of natural gas feedstock in multiple thermal chlorination reactors, each with a natural gas recycle loop. These reactors are arranged in a cross-flow reactor system whereby a gas purge from the first reactor is fed to the second, and so on if necessary until a last reactor, which is vented to the atmosphere by feeding a purge steam to the catalytic reactor.
SUMMARY OF THE INVENTION
Therefore, there is a need for a process that produces methanol in a gas or liquid form. It would be desirable if the process was cost effective, easy to operate, relatively fast, and capable of achieving high conversion.
The present invention provides a method for converting methane to methanol by providing a methane source, contacting the methane with chlorine, exposing the mixture to a light source to form methyl chloride; converting the methyl chloride to methanol and hydrochloric acid; converting the hydrochloric acid to chlorine; and purifying the methanol. The light source may be selected from visible light, ultraviolet light and mixtures thereof. In one embodiment the light source is an ultraviolet lamp that is positioned to pass through an ultraviolet transmission surface. The light source is an ultraviolet lamp which includes the ultraviolet wavelength range of 300-400 nm. The methane is sourced from natural gas, coal-bed methane, regasified liquefied natural gas, gas derived from gas hydrates and/or chlathrates, gas derived from anaerobic decomposition of organic matter or biomass, gas derived in the processing of tar sands, synthetically produced natural gas or alkanes, or mixtures of these sources. For example, the methane source may be from natural or synthetically produced alkanes, natural or synthetically produced natural gas, it may also be produced from the recently developed technology involving methane in shale formations—so called “fracking” process. In addition the methane may in some cases be pretreated by saturating the methane with water.
The present invention also provides a method for converting a gaseous alkane to an alkane alcohol by providing a gaseous alkane source, contacting the alkane with a halogen; exposing the alkane to a light source to form an alkane halide; converting the alkane halide to an alkane alcohol and a hydrogen halide acid; converting the hydrogen halide acid to a halide; and purifying the alkane alcohol. The light source may be selected from visible light, ultraviolet light and mixtures thereof.
The present invention provides a process of reacting chlorine with methane to form methanol by contacting the methane with chlorine; exposing the methane to a light source to form methyl chloride; converting the methyl chloride to methanol and hydrochloric acid; converting the hydrochloric acid to chlorine; and purifying the methanol.
The present invention also provides a method for converting methane to methanol comprising the steps of subjecting a mixture of methane and water to light in the presence of chlorine to form methyl chloride; and converting the methyl chloride to methanol.
The present invention also provides a method for reacting methane and water to produce methanol and hydrogen by providing a methane source to provide methane; contacting the methane with chlorine; exposing the mixture to a light source to form methyl chloride; converting the methyl chloride to methanol and hydrochloric acid; converting the hydrochloric acid to chlorine; and purifying the methanol.
BRIEF DESCRIPTION OF THE DRAWINGS
None.
DETAILED DESCRIPTION OF THE INVENTION
While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention.
To facilitate the understanding of this invention, a number of terms are defined below. Terms defined herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as “a”, “an” and “the” are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention, but their usage does not delimit the invention, except as outlined in the claims.
As used herein, the term “Alkanes” denotes but is not limited to methane, ethane, propane, butane, isobutene, pentanes, hexanes, and/or cyclohexane, etc.
As used herein, the term “The feed stock” denotes but is not limited to natural gas, associated gas, coal-bed methane, residual hydrocarbon fractions, biomass and/or coal, and shales.
The present inventor realized that there is a need for a process that produces methanol in a process that is cost effective, easy to operate, relatively fast, and capable of achieving high conversion. One common source of methane can be natural gas. Although inexpensive and abundant, natural gas presents difficulties in its use caused by the fact that it contains a number of constituents besides methane including nitrogen, ethane, inerts and carbon dioxide.
The present inventor realized that efficient synthesis of methanol from methane has been an elusive target for many years. It is difficult, if not impossible, because of a basic problem based on the chemistry of methane.
Even if one is able to efficiently convert one of the 4 carbon-hydrogen bonds in methane, the conversion will not stop there because the remaining carbon-hydrogen bonds are weakened by the conversion, and the attacking reagent can easily break the remaining carbon-hydrogen bonds. The present invention offers a novel way to synthesize methanol from methane via chlorine chemistry.
The skilled artisan will recognize the reactions involved.
One aspect of the invention provides a process to convert alkanes into alcohols and more specifically to a process to convert methane into methanol. In a first step, methane is mixed with chlorine and exposed to an ultraviolet light source to form methylchloride and hydrochloric acid. In the second step, methylchloride is mixed with water to form methanol and hydrochloric acid. In a third step, the hydrochloric acid is mixed with oxygen to form water and regenerate the chlorine. The skilled artisan will understand how to prepare these reaction chambers for the reaction, and connect the reagents and products for optimal reactivity.
The process includes halogenating one or more alkanes with one or more halogens to form one or more alkane halides and one or more hydrogen halide acids through the exposure to an ultraviolet light source. The one or more alkane halides are reacted with water to form an alkane alcohol and one or more hydrogen halide acids. The one or more hydrogen halide acids then reacted with oxygen to regenerate one or more halogens and water. The net reaction includes the reaction of one or more alkanes with oxygen with the exposure to an ultraviolet light source to produce an alkane alcohol. It should be noted that the term “one or more” applies for the production of a monohydric alcohol or an alcohol containing more than one hydroxide functionality. The conversion of methane to methyl alcohol is the prime, but not the only desired alcohol-forming reaction. To repeat, to produce mainly methanol, methane is reacted with chlorine to form chloromethane and hydrochloric acid through exposure to a source of ultraviolet light. A specific example includes the conversion of methane to methanol. The process includes halogenating methane with chlorine to form methylchloride and hydrochloric acid through the exposure to an ultraviolet light source. The methylchloride is reacted with water to form methanol and hydrochloric acid. The hydrochloric acid then reacts with oxygen to regenerate chlorine and water. The net reaction is the conversion of methane and oxygen to methanol with the exposure to ultraviolet light.
Generally, alkanes (methane, ethane, propane, butane, isobutene, pentanes, hexanes, and cyclohexane, etc.) react with molecular chlorine to form alkylchlorides. High conversions of methane and very good selectivity to methanol are expected because the cycle is very efficient.
In the operation of the method and apparatus, chlorine is received from a suitable source through a line and is directed to a chlorine storage container. Although this specific example uses chlorine the skilled artisan will readily understand that other halogens may be used to form the “halogenation cycle”. Methane from a suitable source is directed to the reactor. Within the reactor the methane and the chlorine are mixed together at an appropriate temperature and exposed to a source of ultraviolet radiation thereby converting the methane and the chlorine to methyl chloride (CH 3 Cl) and hydrogen chloride (HCl). From the reactor, the CH 3 Cl, the HCl, and any unreacted methane and by-products CH 2 Cl 2 , CHCl 3 , and CCl 4 are directed to a condenser through a line. The by-products CH 2 Cl 2 , CHCl 3 , and CCl 4 are sent through a line to a converter to react with methane. In the converter, methane reacts with the by-products CH 2 Cl 2 , CHCl 3 , and CCl 4 to form CH 3 Cl. The newly formed CH 3 Cl and unreacted CH 2 Cl 2 , CHCl 3 , and CCl 4 and methane are sent to the condenser. From the condenser methane, HCl, and CH 3 Cl are sent to a converter. In the converter HCl and CH 3 Cl are converted to CH 3 OH, and H 2 O, which are sent to a separator along with unreacted methane and CH 3 Cl. In the separator, methanol/water are separated as products and recovered. The methanol is subsequently removed from the water. CH 3 Cl is sent back to the converter and methane from the separator is sent back to the chlorination reactor. In the converter, the chloride is regenerated, while the chlorine and unreacted oxygen are sent to a condenser, after which they are separated in a separator. The chlorine is sent to the storage container, while the oxygen is sent to the converter through a blower and a line. From the converter, the water, chloromethane, and methane are separated in a separator. Methane is recycled to the converter, chloromethane is sent to the reactor, water is sent to the reactor. In the reactor, chloromethane reacts to form methanol.
It would be possible to feed a stream of methane containing methyl chloride to the hydrolysis reactor, the simplest procedure is to separate methyl chloride from unreacted methane beforehand. The methyl chloride can be scrubbed from the methane by absorption in, for example, a refrigerated stream of perchloroethylene. The separated methane is recycled to the chlorination reactor.
The overall reaction is isothermic and therefore may be driven by fractional recovery of higher chlorides and removal of chloromethane from the reaction mixture, all in the presence of excess methane. In the embodiment, a biomass is gasified in a gasification step to produce methane; however in other embodiments, methane could be provided in the gas phase initially. The present invention may be used for the conversion of hydrocarbonaceous feed stocks into normally liquid and/or normally solid hydrocarbons. The feed stock (e.g. natural gas, associated gas, coal-bed methane residual hydrocarbon fractions, biomass and/or coal) is converted to methanol.
It is contemplated that any embodiment discussed in this specification can be implemented with respect to any method, kit, reagent, or composition of the invention, and vice versa. Furthermore, compositions of the invention can be used to achieve methods of the invention.
It will be understood that particular embodiments described herein are shown by way of illustration and not as limitations of the invention. The principal features of this invention can be employed in various embodiments without departing from the scope of the invention. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific procedure described herein. Such equivalents are considered to be within the scope of this invention and are covered by the claims.
All publications and patent applications mentioned in the specification are indicative of the level of skill of those skilled in the art to which this invention pertains. All publications and patent applications are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.
The use of the word “a” or “an” when used in conjunction with the term “comprising” in the claims and/or the specification may mean “one”, but it is also consistent with the meaning of “one or more”, “at least one”, and “one or more than one”. The use of the term “or” in the claims is used to mean “and/or” unless explicitly indicated to refer to alternatives only or the alternatives are mutually exclusive, although the disclosure supports a definition that refers to only alternatives and “and/or”. Throughout this application, the term “about” is used to indicate that a value includes the inherent variation of error for the device, the method being employed to determine the value, or the variation that exists among the study subjects.
As used in this specification and claim(s), the words “comprising” (and any form of comprising, such as “comprise” and “comprises”), “having” (and any form of having, such as “have” and “has”), “including” (and any form of including, such as “includes” and “include”) or “containing” (and any form of containing, such as “contains” and “contain”) are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.
The term “or combinations thereof’ as used herein refers to all permutations and combinations of the listed items preceding the term. For example, “A, B, C, or combinations thereof is intended to include at least one of: A, B, C. AB, AC, BC, or ABC, and if order is important in a particular context, also BA, CA, CB, CBA, BCA, ACB, BAC, or CAB. Continuing with this example, expressly included are combinations that contain repeats of one or more item or term, such as BB, AAA, MB, BBC, AAABCCCC, CBBAAA, CABABB, and so forth. The skilled artisan will understand that typically there is no limit on the number of items or terms in any combination, unless otherwise apparent from the context.
All of the compositions and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the compositions and/or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the invention. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention as defined by the appended claims. | The present invention includes a method for converting methane to methanol by providing a methane source to provide methane; contacting the methane with chlorine; exposing the methane to a light source to form methyl chloride; converting the methyl chloride with H20 to methanol and hydrochloric acid; converting the hydrochloric acid to chlorine; and purifying the methanol.
The chemical cycle can be applied to the synthesis of alkane alcohols higher than methanol where appropriate. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a connector having a mechanism for pressing contacts against a flexible printed circuit board or flexible flat cable for use in a mobile phone or cellular phone, notebook personal computer, digital camera and the like, and more particularly to a connector capable of inserting contacts in parallel with insertion grooves of its housing.
Among the connectors for use in mobile phones, charge couples device (CCD) cameras and the like, connectors of one kind mainly comprise a housing and contacts, and a flexible printed circuit board is inserted into the housing to be brought into contact with contact portions of the contacts. This type of connectors is so-called “non-zero-insertion force” (NZIF) type. The connectors of the other kind mainly comprise a housing, contacts and a slider so that a flexible printed circuit board is embraced by the housing and the slider. The connectors of this type are so-called “zero-insertion force” (ZIF) type or “piano touch” type. There may be various methods for holding the flexible printed circuit board by the housing and the slider. In many cases, after a flexible printed circuit board has been inserted into the housing, the slider is inserted to press the board against the contacts, or after a flexible printed circuit board has been inserted, the slider is pivotally moved to press the board against the contacts.
The housing is formed with a required number of insertion grooves into which the contacts are inserted and further formed with a fitting opening into which a flexible printed circuit board is inserted.
The contacts each mainly comprise a contact portion adapted to contact a flexible printed circuit board, a connection portion to be connected to a hard board or the like, and a fixed portion to be fixed to the housing. These contacts are fixed to the housing as by press-fitting.
Typically shown are a patent literature 1 (Japanese Utility Model Application Opened No. H6-60,983/1994) for the Z 1 F type connector and a patent literature 2 (Japanese Patent Application Opened No. H13-257,020/2001) for the piano touch type connector. The applicant of the present application has proposed a connector disclosed in a patent literature 3 (Japanese Patent Application No. 224,340/2002) which is capable of securely pressing a flexible printed circuit board or flexible flat cable against contact portions of contacts and is able to achieve even narrower pitches of contacts and minimization of height or lower geometry.
Patent Literature 1
Japanese Utility Model Application Opened No. H6-60,983/1994 discloses one example of the “zero-insertion force” type connectors. As can be seen from the “Abstract” of the Japanese Utility Model, this invention relates to a connector with a slider for a print board for use in a narrow space in an electronic or communication appliance. The slider is formed at the ends on both sides with U-shaped arms with their proximal ends fixed to the slider as guiding means when being inserted into a housing. The U-shaped arms are each provided on its opening side with a projection and formed with a notch such that the opening end is visible from the inserting side. The housing is provided at both the ends with projections having an oblique surface adapted to engage the projection of the slider. When the slider together with connection terminals of a flexible printed circuit board is inserted into the housing, the projections of the slider ride over the projections having the oblique surface of the housing so that the opening ends of the U-shaped arms of the slider are temporarily spread outwardly and then returned to their normal positions when the insertion has been completed.
Patent Literature 2
Japanese Patent Application Opened No. H13-257,020/2001 discloses one example of the so-called “piano touch” type connectors. With a view to obtaining an accurate positioning of a flexible printed circuit board or flexible flat cable relative to contacts of the disclosed connector, projections are provided in a row on a line on a terminal block between the contacts. After the flexible printed circuit board or flexible flat cable has been inserted into the terminal block, a slider is moved to press the circuit board or flat cable against the contacts. At the moment when the circuit board or flat cable is thus electrically connected to the contacts with the aid of the slider in this manner, the projections snap into recesses between patterns of the circuit board or flat cable, thereby ensuring positional coincidence between the contacts and patterns of the circuit board or flat cable.
Patent Literature 3
The Japanese Patent Application Opened No. 224,340/2002 discloses a connector which is capable of securely pressing a flexible printed circuit board or flexible flat cable against contact portions of contacts by a slider without degrading strength of respective parts and without detracting specifications, and which is superior in operationality or easy to use and easy to achieve narrower pitches of contacts and minimization of height or lower geometry of the connector. For the purpose of the lower geometry of the connector, the contacts each comprise an elastic portion and a fulcrum portion between the contact portion and a connection portion, and a pressure receiving portion at a position opposite to the connection portion and extending from the elastic portion, and the contact portion, the elastic portion, the fulcrum portion and the connection portion are arranged in the form of a crank. Moreover, the slider is provided with urging portions continuously in its longitudinal direction and is fitted in a housing so that the urging portions can be pivotally movable between the connection portions and the pressure receiving portions of the contacts.
In recent years, with miniaturization of electrical and electronic appliances, the requirement for the lower vertical geometry or minimization of height has put even more severe requirement on the connectors of this kinds using the flexible printed circuit board or flexible flat cable. With the connectors having the general construction, as is found in the patent literature 3, there are six layers in height, that is, the upper and lower walls of the housing, the contact portion and the pressure receiving portion of each of the contacts, the urging portion of the slider and the flexible printed circuit board or flexible flat cable. In order to reduce the connector's height as much as possible, it is possible to omit the pressure receiving portion of each of the contacts to obtain five layers in height (the upper and lower walls of the housing, the contact portion of each of the contacts, the urging portion of the slider and the flexible printed circuit board or flexible flat cable). It is however impossible to more reduce the height of the connector in consideration of strength of the respective members and specifications or customer's demands. Moreover, the insertion of the circuit board or flat cable and urging of the contact portions of the contacts against the circuit board or flat cable take place only on the side of the fitting opening of the housing for the circuit board or flat cable, so that as the connector is miniaturized, such operations would become more difficult. In order to overcome such problems, the applicant has proposed the connector disclosed in the patent literature 3, which is capable of securely pressing the contact portions of the contacts against the flexible printed circuit board or flat cable without degrading the strength of the respective members and without detracting specifications and is superior in operationality or easy to use and easy to achieve narrower pitches of contacts and minimization of height or lower geometry of the connector.
With the construction of the connector as disclosed in the patent literature 3, however, when the contacts are inserted into the housing, the contacts are obliquely inserted with their contact portions relative to the wall of the housing in amount corresponding to clearances between the contacts and insertion grooves of the housing, resulting in irregular contact pressures, making the contact between the contacts and the board unstable. This problem remains to be solved.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved connector which overcomes the above problems of the prior art and which can achieve stable connection between contacts and a flexible printed circuit board or flat cable without obliquely inserting the contacts into the housing of the connector.
The above object can be achieved by the connector to be detachably fitted with a flexible printed circuit board or a flexible flat cable according to the invention, comprising a required number of contacts having a contact portion to contact the flexible printed circuit board or flexible flat cable, a housing for holding and fixing therein the contacts and having a fitting opening for inserting the flexible printed circuit board or flexible flat cable, and a slider for pressing the flexible printed circuit board or flexible flat cable against the contacts, the contacts each having an elastic portion and a fulcrum portion between the contact portion and a connection portion, and a pressure receiving portion at a location opposite to the connection portion and extending from the elastic portion, and the contact portion, the elastic portion, the fulcrum portion, and the connection portion being arranged in the form of a crank, and the slider being provided with urging portions continuously in its longitudinal direction and being fitted in the housing so that the urging portions are pivotally movable between the connection portions and the pressure receiving portions of the contacts, wherein the housing comprises anchoring portions at locations corresponding to the connection portions of the contacts, and the connection portions of the contacts each comprise an oblique recess to engage the anchoring portion.
Moreover, the above object can also be accomplished by the connector to be detachably fitted with a flexible printed circuit board or a flexible flat cable, comprising a required number of contacts having a contact portion to contact the flexible printed circuit board or flexible flat cable, a housing for holding and fixing therein the contacts and having a fitting opening for inserting the flexible printed circuit board or flexible flat cable, and a slider for pressing the flexible printed circuit board or flexible flat cable against the contacts, the contacts consisting of two kinds of contacts which are arranged alternately staggered, the contacts of the one kind each having an elastic portion and a fulcrum portion between the contact portion and a connection portion, and a pressure receiving portion at a location opposite to the connection portion and extending from the elastic portion, and the contact portion, the elastic portion, the fulcrum portion, and the connection portion being arranged in the form of a crank, and the contacts of the other kind each having an elastic portion and a fulcrum portion between the contact portion and a connection portion, and a pressure receiving portion extending from the elastic portion in an opposite direction to the contact portion, and the contact portion, the elastic portion, the fulcrum portion and the connection portion being arranged in the form of a U-shape, and the slider being provided with urging portions continuously in its longitudinal direction and being fitted in the housing so that the urging portions are pivotally movable between the connection portions and the pressure receiving portions of the contacts of the one kind and between the housing and the pressure receiving portions of the contacts of the other kind, wherein according to the invention the housing comprises anchoring portions at locations corresponding to the connection portions of the contacts, and the connection portions of the contacts each comprise an oblique recess to engage the anchoring portion.
According to the invention, the contacts are installed in the connector in the manner that when the contacts are inserted into the housing from the opposite side of the fitting opening, the contact portions of the contacts are substantially parallel to insertion grooves of the housing during a stage at the beginning of engagement of the anchoring portions of the housing with the recesses, but on proceeding of the insertion the contacts are obliquely inclined so that the contact portions contact upper walls of the insertion grooves, and when the insertion has been completed, the contact portions return into parallel with the insertion grooves with the aid of said oblique recesses.
With the connector according to the invention, after a flexible printed. circuit board has been inserted into the housing of the connector, the slider is pivotally moved in the insertion direction of the circuit board to raise the pressure receiving portions of the contacts by the urging portions of the slider so that the elastic portions of the contacts are tilted toward the contact portions about the fulcrum portions of the contacts, thereby securely pressing the contact against the flexible printed circuit board or flat cable.
The connector according to the invention can bring about the following significant functions.
(1) According to the invention, the connector to be detachably fitted with a flexible printed circuit board or a flexible flat cable comprises a required number of contacts having a contact portion to contact the flexible printed circuit board or flexible flat cable, a housing for holding and fixing therein the contacts and having a fitting opening for inserting the flexible printed circuit board or flexible flat cable, and a slider for pressing the flexible printed circuit board or flexible flat cable against the contacts, the contacts each having an elastic portion and a fulcrum portion between the contact portion and a connection portion, and a pressure receiving portion at a location opposite to the connection portion and extending from the elastic portion, and the contact portion, the elastic portion, the fulcrum portion, and the connection portion being arranged in the form of a crank, and the slider being provided with urging portions continuously in its longitudinal direction and being fitted in the housing so that the urging portions are pivotally movable between the connection portions and the pressure receiving portions of the contacts, wherein the housing comprises anchoring portions at locations corresponding to the connection portions of the contacts, and the connection portions of the contacts each comprise an oblique recess to engage the anchoring portion. With this construction, the connector according to the invention achieves its remarkable minimization in height less than 0.9 mm. Moreover, even if there are clearances between the contacts and the insertion grooves of the housing, the contacts are inserted and fixed in the insertion grooves in parallel therewith without any inclination, thereby achieving stable connection between the contacts and a flexible printed circuit board or flat cable. (2) According to the invention, the connector to be detachably fitted with a flexible printed circuit board or a flexible flat cable, comprises a required number of contacts having a contact portion to contact the flexible printed circuit board or flexible flat cable, a housing for holding and fixing therein the contacts and having a fitting opening for inserting the flexible printed circuit board or flexible flat cable, and a slider for pressing the flexible printed circuit board or flexible flat cable against the contacts, the contacts consisting of two kinds of contacts which are arranged alternately staggered, the contacts of the one kind each having an elastic portion and a fulcrum portion between the contact portion and a connection portion, and a pressure receiving portion at a location opposite to the connection portion and extending from the elastic portion, and the contact portion, the elastic portion, the fulcrum portion, and the connection portion being arranged in the form of a crank, and the contacts of the other kind each having an elastic portion and a fulcrum portion between the contact portion and a connection portion, and a pressure receiving portion extending from the elastic portion in an opposite direction to the contact portion, and the contact portion, the elastic portion, the fulcrum portion and the connection portion being arranged in the form of a U-shape, and the slider being provided with urging portions continuously in its longitudinal direction and being fitted in the housing so that the urging portions are pivotally movable between the connection portions and the pressure receiving portions of the contacts of the one kind and between the housing and the pressure receiving portions of the contacts of the other kind, wherein the housing comprises anchoring portions at locations corresponding to the connection portions of the contacts, and the connection portions of the contacts each comprise an oblique recess to engage the anchoring portion. With this construction, therefore, the connector according to the invention achieves its remarkable minimization in height less than 0.9 mm and also achieves even narrower pitches of the contacts. Moreover, even if there are clearances between the contacts and the insertion grooves of the housing, the contacts are inserted and fixed in the insertion grooves in parallel therewith without any inclination, thereby achieving stable connection between the contacts and a flexible printed circuit board or flat cable. (3) According to the invention, the contacts are inserted into the housing from the opposite side of the fitting opening, the contact portions of the contacts are substantially parallel to insertion grooves of the housing during a stage at the beginning of engagement of the anchoring portions of the housing with the recesses, but on proceeding of the insertion the contacts are obliquely inclined so that the contact portions contact upper walls of the insertion grooves, and when the insertion has been completed, the contact portions return into parallel with the insertion grooves with the aid of the oblique recesses. With such a construction of the connector according to the invention, even if the contacts are obliquely inserted into the insertion grooves of the housing due to clearances between the contacts and the insertion grooves, the contacts finally return to parallel position to the insertion grooves, thereby obtaining stable connection between the contacts and a flexible printed circuit board or flat cable.
The invention will be more fully understood by referring to the following detailed specification and claims taken in connection with the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a perspective view of a connector of one embodiment according to the invention viewed from the side of its fitting opening for inserting a flexible printed circuit board or flat cable;
FIG. 1B is a perspective view of a connector with contacts arranged in staggered or zigzag fashion of another embodiment according to the invention viewed from the side of its fitting opening;
FIGS. 2A to 2D are views for explaining successive steps when contacts are inserted into the housing of the connector according to the invention; FIG. 3A is a partly sectional perspective view of the connector according to the invention before the contacts are inserted into the housing; and
FIG. 3B is a partly sectional perspective view of the connector according to the invention after a flexible printed circuit board has been inserted into the housing and the slider has been pivotally moved.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A connector 10 according to the invention will be explained with reference to the drawings. FIG. 1A is a perspective view of the connector according to the invention viewed from the side of its fitting opening, and FIG. 1B is a perspective view of the connector with contacts arranged in staggered or zigzag fashion, viewed from the fitting opening. FIGS. 2A to 2D are explanatory views for mounting contacts in its housing. FIG. 3A is a partly sectional perspective view of the connector before a flexible printed circuit board is inserted therein and FIG. 3B is a partly sectional perspective view of the connector after the flexible printed circuit board has been inserted and a slider has been pivotally moved. The connector 10 according to the invention mainly comprises the housing 12 , the slider 16 and the contacts 14 .
The components of the connector 10 according to the invention will be explained by referring to the drawings. First, the contacts 14 forming one important aspect of the invention will be explained. The contacts 14 are formed by the known press-working from a metal. Preferred metals from which to form the contacts 14 include brass, beryllium copper, phosphor bronze and the like to fulfil the requirements imposed thereon such as springiness, conductivity and the like.
As shown in FIG. 3A , the contact 14 is substantially “H-shaped” and mainly composed of an upper contact portion 22 adapted to contact the flexible printed circuit board 40 or a flexible flat cable, a connection portion 24 adapted to be connected to a board or substrate, a fixed portion to be fixed to the housing 12 , an elastic portion 34 and a fulcrum portion 32 provided between the contact portion 22 and the connection portion 24 , a pressure receiving portion 20 positioned opposite to the connection portion 24 and extending from the elastic portion 34 , and a further or lower contact portion 22 extending from the fulcrum portion 32 and adapted to contact the flexible printed circuit board 40 or the flexible flat cable. The upper contact portion 22 (positioned on the upper side viewed in FIG. 3A ), the elastic portion 34 , the fulcrum portion 32 and the connection portion 24 are arranged substantially in the form of a crank. The contact portions 22 are each formed with a protrusion at a free end to facilitate contacting with the flexible circuit board 40 or flat cable. Although the connection portions 24 are shown as a surface mounting type (SMT) in the embodiment shown in FIG. 1 , it will be apparent that they may be of a dip type. In the illustrated embodiment, there are provided the two contact portions 22 to embrace therebetween a flexible printed circuit board 40 or a flexible flat cable. In more detail, by providing the two contact portions 22 on each contact on both the sides of the insertion direction of the flexible printed circuit board or flexible flat cable to embrace the board or cable therebetween, thereby achieving a reliable connection therebetween.
The contacts 14 are each formed in its connection portion with an oblique recess 42 adapted to engage an anchoring portion 44 (later described) formed on the housing 12 . The oblique recess 42 serves as a guide when the contact 14 is mounted in the housing 12 . The shape and size of the recess 42 may be suitably designed so that it operates in a manner described below. In the illustrated embodiment, the recess is an oblique notch and 0.08 mm in size.
The contacts 14 are mounted in the housing 12 in the following manner which will be explained by referring to FIGS. 2A to 2D . The contact 14 is inserted into the housing 12 in the direction shown by an arrow B from the opposite side of the fitting opening 18 as shown in FIG. 2A . At the commencement of the engagement of the anchoring portion 44 of the housing 12 with the oblique recess 42 of the contact 14 , the contact portions 22 of the contact 14 is substantially in parallel with an inserting hole 38 of the housing 12 as shown in FIG. 2B . When the contact 14 is further inserted into the housing 12 , the contact will be tilted by clearances between the contact 14 and the inserting hole 38 of the housing 12 so that the upper contact portion 22 of the contact 14 comes into contact with the upper wall of the inserting hole 38 as shown in FIG. 2C . When the insertion of the contact has been completed, the upper contact portion 22 of the contact has returned into parallel with the inserting hole 38 because the contact 14 has been guided by its oblique recess 42 as shown in FIG. 2D .
The fulcrum portion 32 , the elastic portion 34 and the pressure receiving portion 20 will achieve the following functions when a flexible printed circuit board 40 or flexible flat cable is inserted into the connector. After the flexible printed circuit board 40 or flexible flat cable has been inserted into the fitting opening 18 of the housing 12 , urging portions 36 of a slider 16 are pivotally moved between the connection portions 24 and the pressure receiving portions 20 of the contacts 14 to raise the pressure receiving portions 20 by the urging portions 36 so that the elastic portions 34 of the contacts 14 are tilted toward the contact portions 22 about the fulcrum portions 32 , thereby pressing the contact portions 22 against the flexible printed circuit board 40 or flexible flat cable (the slider 16 having the urging portions 36 being explained in detail later). The sizes and shapes of the fulcrum portion 32 , the elastic portion 34 and the pressure receiving portion 20 are suitably designed to perform their functions described above.
It is preferable to provide a projection 26 shown in FIG. 2A at the free end of the pressure receiving portion 20 of the contact 14 to prevent the slider 16 from being deformed at its center in the direction shown by an arrow A in FIG. 1A due to strong reaction against the pivotal movement of the slider 16 when causing its urging portions 36 to pivotally move between the connection portions 24 and the pressure receiving portions 20 of the contacts 14 . The projection 26 may be formed in any size so long as its can perform its function and may be so designed that the urging portion 36 of the slider 16 securely engages the projection 26 .
A contact (not shown) different from the contact 14 described above will be explained. The contact is substantially “h-shaped” which does not have the lower contact portion 22 of the contact 14 .
The housing 12 will then be explained. The housing 12 is injection-molded from an electrically insulating plastic material in the conventional manner. Preferred materials from which to form the housing 12 include polybutylene terephthalate (PBT), polyamide (66PA or 46PA), liquid crystal polymer (LCP), polycarbonate (PC) and the like and combination thereof in view of the requirements imposed on the housing 12 with respect to dimensional stability, workability, manufacturing cost and the like.
The housing 12 is formed with inserting holes 38 in which a required number of contacts 14 are inserted, respectively, and fixed thereat, by press-fitting, hooking (lancing), welding or the like. The housing 12 is formed with the anchoring portions 44 at locations corresponding to the connection portions 24 of the contacts 14 . The anchoring portions 44 serve as guides when the contacts are inserted into the inserting holes 38 of the housing 12 for mounting the contacts therein as described above. The size of the anchoring portions 44 may be suitably designed so as to achieve their function and is of the order of 0.1 mm in the embodiment.
The housing 12 is further provided in the proximity of the longitudinal ends with holes or bearings for rotatably supporting axles 28 of the slider 16 . The holes or bearing of the housing 12 may be in any shape and size so long as the slider 16 can be rotated and may be suitably designed in consideration of their functions and the strength and size of the housing 12 . The housing 12 is further provided at the longitudinal ends with anchoring portions at locations corresponding to locking portions (later described) of the slider 16 .
Finally, the slider 16 will be explained hereafter. The slider 16 is injection-molded from an electrically insulating plastic material in the conventional manner. Preferred materials from which to form the slider 16 include polybutylene terephthalate (PBT), polyamide (66PA or 46PA), liquid crystal polymer (LCP), polycarbonate (PC) and the like and combination thereof in view of the requirements imposed on the slider 16 with respect to dimensional stability, workability, manufacturing cost and the like. The slider 16 mainly comprises axles 28 adapted to be rotatably fitted in the housing 12 , the urging portions 36 for urging the pressure receiving portions 20 of the contacts 14 , and anchoring grooves 30 adapted to be engaged with the projections 26 of the contacts 14 . The axles 28 are fulcrums for the pivotal movement of the slider 16 and fitted in the holes or bearings in the housing 12 at the location in the proximity of its longitudinal ends. The slider 16 is further provided at the longitudinal ends with locking portions adapted to engage the housing 12 for preventing the slider 16 from being lifted (in the upward direction in the drawing) when the pressure receiving portions 20 of the contacts 14 are urged by the urging portions 36 of the slider 16 . The locking portions may be in any size and shape so long as they can engage the housing 12 and may be suitably designed in consideration of their function and the size and strength of the connector 10 .
The urging portions 36 serve to push the pressure receiving portions 20 of the contacts 14 and are preferably of an elongated shape, elliptical in the illustrated embodiment. With such an elliptical shape, when the slider is pivotally moved in the direction shown by an arrow C in FIG. 3A so as to rotate its urging portion in the space between the pressure receiving portions 20 and the connection portions 24 of the contacts 14 , the pressure receiving portions 20 of the contacts 14 are moved upward with variation in contacting height owing to the elliptical shape of the urging portions 36 , resulting in the reliable clamping of the flexible printed circuit board 40 or flat cable by the contact portions 24 of the contacts 14 . The urging portions 36 may be formed in any shape insofar as they can rotate between the pressure receiving portions 20 and the connection portions 24 of the contacts 14 , and the pressure receiving portions 20 of the contacts 14 can be raised with the aid of the variation in contacting height owing to, for example, difference in major and minor axes of an ellipse.
The slider 16 is further provided with the anchoring grooves 30 independently from each other, which are adapted to engage the projections 26 of the contacts 14 for the purpose of preventing the slider 16 from being deformed at the middle in the direction shown by the arrow A in FIG. 1A due to the reaction against the pivotal movement of the slider 16 when being pivotally moved. The independently provided anchoring grooves 30 serve to increase the strength of the slider 16 and to prevent its deformation when being pivotally moved.
Another embodiment of the invention will be explained with reference to FIG. 1B . The connector 101 of this embodiment mainly comprises a housing 121 , contacts 14 and 141 and a slider 161 as is also the case in the connector 10 described above. The subject matter of the connector 101 of this embodiment lies in the fact that the two kinds of the contacts 14 and 141 are arranged to be alternately staggered by inserting the contacts into the housing in opposite directions alternately, thereby achieving narrower pitches of the contacts and lower geometry or minimization of height of the connector. The housing 121 , the slider 161 and the contacts 14 will not be described in further detail since these members are substantially similar to the corresponding members of the connector 10 described above.
The other contacts 141 are also formed by press-working from the metal similar to that of the contacts 14 .
Likewise, the contacts 141 have two types, “h-shaped” and “H-shaped”. The “h-shaped” contact 141 mainly composed of a contact portion 22 adapted to contact the flexible printed circuit board 40 or flexible flat cable, a connection portion 24 adapted to be connected to a board or substrate, a fixed portion to be fixed to the housing, an elastic portion 34 and a fulcrum portion 32 provided between the contact portion and the connection portion 24 , and a pressure receiving portion 20 extending from the elastic portion 34 . The contact portion 22 , the elastic portion 34 , the fulcrum portion 32 and the connection portion 24 are arranged in U-shape. In addition to the respective portions provided in the “h-shaped” contact, the “H-shaped” contact is provided with an extension portion extending from the fulcrum portion 32 in an opposite direction to the connection portion 24 . The contact portions 22 are each formed with a protrusion at a free end to facilitate contacting with the flexible printed circuit board 40 or flexible flat cable. Although the connection portions 24 are of a surface mounting type (SMT) in the embodiment as shown in FIG. 1B , they may be of a dip type.
With the contacts 141 similarly to the contacts 14 , after the flexible printed circuit board 40 or flexible flat cable has been inserted into fitting opening of the housing, the urging portions 36 of a slider 161 are pivotally moved between the pressure receiving portions 20 of the contacts 141 and the housing 121 or between the pressure receiving portions 20 and the extension portions to raise the pressure receiving portions 20 by the urging portions 36 so that the elastic portions 34 of the contacts 141 are tilted toward the contact portions 22 about the fulcrum portions 32 , thereby pressing the contact portions 22 against the flexible printed circuit board 40 or flexible flat cable. The sizes and shapes of the fulcrum portion 32 , the elastic portion 34 and the pressure receiving portion 20 may be suitably designed to perform their functions described above.
Moreover, it is preferable to provide a projection 26 at the free end of the pressure receiving portion 20 of the contact 141 to prevent the slider 161 from being deform at its center in the connection direction (mounting direction of the slider) due to strong reaction against the pivotal movement of the slider 161 when causing its urging portion to pivotally move. However, it may be sufficient to provide the projections 26 only on one kind of the contacts 14 among the two kinds of contacts 14 and 141 because of the strength of the slider 161 improved by narrower pitches of the contacts. The projection 26 may be formed in any size so long as it can perform its function and may be so designed that the urging portion 36 of the slider 161 securely engages the projection 26 .
The present invention is preferably applicable to connectors for use in mobile phones or cellular phones, notebook personal computers, digital cameras and the like and having a mechanism for pressing contacts 14 and 141 against a flexible printed circuit board 40 or flexible flat cable. Particularly, the connector according to the invention is capable of inserting the contacts into a housing to be parallel to insertion grooves without obliquely positioning.
While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details can be made therein without departing from the spirit and scope of the invention. | A connector to be detachably fitted with a flexible printed circuit board or a flexible flat cable includes a required number of contacts, a housing for holding and fixing therein the contacts, and a slider for pressing the circuit board or flat cable against the contacts. The housing is provided with anchoring portions at locations corresponding to connection portions of the contacts. Connection portions of the contacts are each formed with an oblique recess to engage the anchoring portion of the housing. When the contact is being inserted into an insertion groove of the housing, a contact portion of the contact comes into contact with an upper wall of the insertion groove, but on proceeding of the insertion, the contact portion of the contact will return into parallel with the insertion groove with the aid of guidance of the engagement of the oblique recess with the anchoring portion of the housing without any oblique positioning of contacts, thereby achieving stable electrical connection of the connector. | 7 |
RELATED APPLICATIONS
[0001] This application is a continuation of, and claims the benefit of, earlier filed U.S. patent application Ser. No. 09/920,072 filed Aug. 1, 2001, which claimed priority to U.S. provisional patent application Ser. No. 60/225,623 filed Aug. 15, 2000. Both of these applications are incorporated herein by reference. This application also incorporates by reference, patent application Ser. No. 11/092,120, now issued as U.S. Pat. No. 7,640,510.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to the management of an interaction between an agent and a person using prerecord scripts played using a computer system. More particularly, the present invention relates to a script playing system which can play prerecorded scripts of both informational content and conversational content in a fashion that mimics a conversation between two actual people.
[0004] 2. Technical Background
[0005] In the sales business, telephone marketing is essential. Simply put, the more potential customers you contact, the more potential sales you will have. In the telemarketing business, many people are employed to contact potential customers. These employees typically have a script to read from so that the sales pitch is uniform and important information is not left out. Although market research may determine the best information to present to a particular type of customer contact, different agents present the material in different ways, and the way in which the agent communicates with a potential customer or contact is often the difference between a sale and a rejection. To that end, professional voice actors may be employed to deliver scripted information and content to contacts and potential customers. Ultimately, the voice actor records scripts to be played by multiple sales agents.
[0006] The problem with many existing calling systems however, is that they are inflexible in responding to a customer. A prerecorded script cannot respond with pertinent information to a presently-asked question. Perhaps most importantly, potential customers are often turned off by the fact that they are not talking to a live person, but rather a recording. A dialog between the calling system and the live contact may be disjointed because a computer controls the navigation and playing of the scripts and a particular prerecorded response selected by the computer may not precisely match the response by the contact. Another problem with many calling systems is that a human agent cannot interject into the dialog to respond to a concern by the contact, either by live-voice, or by a prerecorded interjection that is not part of a preplanned sales dialog.
[0007] Further, most existing calling systems do not keep track of data presented by the system and received by the contact. Nor can these systems verify information provided by the contact.
[0008] Presently known calling systems that play prerecorded scripts, either do not allow for interjection by a human voice, or do not allow the transparent switch from computer to human voice without a difference in sound or quality that is obvious to the contact. Further, existing telephone calling systems do not allow the seamless transition in content between a live voice and a prerecorded script.
[0009] Thus, it would be an advancement in the art to provide a calling system and method for contacting a customer that is flexible in the way content is presented to a customer. It would be an additional advancement in the art to provide such a system and method that could be used with outgoing calls. It would be another advancement if a variety of prerecorded content could be provided and easily negotiated by a sales agent. It would be an additional advancement in the art to provide a system and method that could keep track of important calling and contact data. It would be yet an additional advancement in the art to provide a system and method for seamlessly and transparently integrating an agent's live voice with a prerecorded voice by someone other than the agent. It would be another advancement to provide a system and method that was easy to utilize and navigate between scripts to form a dialog that was not disjointed. Such a system and method in accordance with the present invention is disclosed and claimed herein.
SUMMARY OF THE INVENTION
[0010] The present invention solves many or all of the foregoing problems by introducing a system and method by which an agent can initiate or receive a call and seamlessly and selectively transition between prerecorded scripts and/or the agents live voice.
[0011] In one embodiment, the calling system includes an output device for providing audio outputs from an agent. The system also includes an input device for receiving audio inputs from a contact. A player for outputting scripted voice waveforms over a phone line to a contact is also included. A signal processor is configured to provide a normalized signal selected from the output device and the player.
[0012] The signal processor may match the signal-to-noise ratio of the input coming into the signal processor and the output going out. In one preferred embodiment, the player provides an input to the signal processor which provides an output having a signal-to-noise ratio substantially the same as the signal-to-noise ratio of the output device. Accordingly, the signal processor can normalize a first voice waveform received from the output device and a second voice waveform received from the player so that they sound the same to the contact. This can be accomplished because the telephone system has a limited band width that carries the voice. Additionally, the sound card adjusts the microphone volume of the telemarketing agent to match the volume of the pre-recorded script. Because both the voice of the telemarketing agent and the sound of the prerecorded script pass through the same amplifier system, and then through the limited band of the telephone line, the sound quality of the telemarketing agent and the pre-recorded script are the same. The hardware acts as a filtering element for both sources of sound.
[0013] The system also includes a computer having a processor and a memory device. The memory device stores a script module which is executable on the processor. The system is configured to provide an output having a bandwidth greater than the response bandwidth of a telephone network. Thus, the system acts as a filter to make it difficult for the contact to tell the difference between the prerecorded scripts played by the system and the human agent's voice spoken through the system.
[0014] In one aspect of the invention, a calling system includes a script module configured to provide recorded voice waveforms and an integration module configured to interface between an agent and the script module. The script module may include a script player for playing the recorded voice waveforms. In one preferred embodiment, the recorded waveforms are selected from computer generated wave files, audio recordings, synthesized voice, and actual voices. The system allows the recorded waveforms to be selectively provided by a human agent.
[0015] The integration module may include a telephone interface module to facilitate interaction with the system and a telephone system. In one embodiment, the telephone interface module allows a human agent to initiate a call to a contact. In one embodiment, a human agent or a computer dialer may initiate a call to a contact. The computer program allows the telemarketing agent to login and select a type of voice for the prerecorded script. For example, the telemarketer may be a female with a low voice and she would select the script that has been pre-recorded in a low speaking female's voice.
[0016] The integration module allows the execution of an interaction protocol by a human agent for interacting with a contact. The interaction protocol allows the agent to select and present content to a contact in the selected voice type and pose a question or statement to a contact in response to a contact's response or statement. The integration module may include a mode module to allow a sales agent to select between one of live voice interaction, script interaction, and interjection interaction between the agent and a contact. The hardware and software make it difficult for an untrained ear to tell the difference between the pre-recorded script and the live voice of the telemarketer.
[0017] The program may present to the telemarketing agent a number of options on the monitor. On one side of the monitor are shown scripted responses that are standard in general conversations such as an affirmative response, a negative response, or a laugh. On the other side of the screen are anticipated responses that the potential customer may make in answer to the live telemarketing agent's initial questions.
[0018] For example, the live telemarketer's initial question is usually a yes or no question and, depending upon the potential customer's response, she would type in a letter ' corresponding to the customer's response; in this case “yes” or “no.” This selection by the telemarketer would play a pre-recorded message ending in a question, to which the potential customer could give a limited number of responses. Those anticipated responses are shown on the screen and depending upon the response given by the potential customer, the telemarketer would click on that response. The next pre-recorded script would play ending in questions capable of being answered in a finite number of ways which would be shown on the screen. In this way, the potential customer's answers to questions are anticipated and responses to those answers are pre-recorded. The telemarketing agent simply clicks on the answer given by the potential customer and in that way can control the branching of a dialog between the potential customer and the recorded script. At any time during the process, the telemarketing agent can pause the program and talk live with the customer. This might happen when the customer gives a response that was not anticipated and for which there is no counter response that has been pre-recorded. The program also allows the telemarketing agent to move back up the dialog branch and click on different pre-recorded responses that would answer the potential customer's questions or statements.
[0019] Accordingly, this invention allows the telemarketing agent to flexibly control the direction of the dialogue with a potential customer using branching techniques and script positioning to play pre-recorded responses to any one of many potential questions or statements by the potential customer. In this way, the potential customer has the illusion of talking to a responsive, live telemarketing agent.
[0020] In one embodiment, the includes a database module for storing and retrieving data. The database module may be able to update a contact file and keep a record of which scripts were played during an interaction between the agent and a contact.
[0021] The method for contacting a customer may include the steps of providing an integrated system for interaction with a contact, the interaction being selectable between human and computer delivery. An interaction protocol may then be executed to create an interaction with the contact. A call may be placed to a contact and responses to a contact from a human agent and a recorded script can be selectively interwoven into the call.
[0022] The step of interweaving responses in the agent's live script and in pre-recorded script further includes listening by the human agent to a response from the contact. The agent may then select and present content to the contact. The agent may then pose a question to the contact and repeat the process of listening to the contact and selecting and presenting more content. At any time, the agent may decide to intervene into the dialog and present content via live voice or prerecorded script. The method of customer contacting may also include validating sales information and keeping a history of recorded scripts played.
[0023] Accordingly, the present invention provides a client-initiated program and method of using same for providing outgoing calls. The invention may provide human voice or pre-recorded scripts that are flexible in the way content is presented and easily negotiated.
[0024] The present invention also provides a program that allows for live validation of sale information (i.e. credit card information, etc.) and allows the operator to maintain and update a customer profile. The system and method of the present invention also allows the program to keep an historical record of which pre-recorded tracks were played by the sales agent and in what order. Thus, promises or statements which the customer alleges were made by the sales agent can be verified or denied with a tangible record. The system of the present invention provides for the seamless and transparent integration of an agent's live voice with a prerecorded voice by someone other than the agent.
[0025] These and other features and advantages of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] To better understand the invention, a more particular description of the invention will be rendered by reference to the appended drawings. These drawings only provide information concerning typical embodiments of the invention and are not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:
[0027] FIG. 1 is a schematic block diagram of a computer system suitable for implementing one embodiment of the invention;
[0028] FIG. 2 is a schematic block diagram of the physical components of one embodiment of a calling system which incorporates the computer system of FIG. 1 ;
[0029] FIG. 3 is a schematic block diagram of the system of FIG. 2 , showing an integration module for providing seamless live-voice and prescripted integrated and interactive customer contacting according to one embodiment of the present invention;
[0030] FIG. 4 is a schematic block diagram of a voice transition module of the system of FIG. 3 according to one embodiment of the present invention;
[0031] FIG. 5 is a schematic block diagram illustrating a script module of the embodiment of FIG. 2 , showing a script module for providing and playing prerecorded script options according to one embodiment of the present invention;
[0032] FIG. 6 is a user interface displaying various options for a user of the system and method of the present invention; and
[0033] FIG. 7 is a flow diagram of a method of the present invention.
[0034] The figures depict embodiments of the present invention for purposes of illustration only. Those skilled in the art will readily recognize from the following discussion that alternative embodiments of the illustrated structures and methods may be employed without departing from the principles of the invention described herein.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0035] Certain preferred embodiments of a system in accordance with the invention are now described with reference to the FIGS. 1-7 , where like reference numbers indicate identical or functionally similar elements. The components of the present invention, as generally described and illustrated in the Figures, may be implemented in a wide variety of configurations. Thus, the following more detailed description of the embodiments of the system and method of the present invention, as represented in the FIGS. 1-7 , is not intended to limit the scope of the invention, as claimed, but is merely representative of presently preferred embodiments of the invention.
[0036] Various components of the invention are described herein as “modules.” In various embodiments, the modules may be implemented as software, hardware, firmware, or any combination thereof. For example, as used herein, a module may include any type of computer instruction or computer executable code located within a memory device and/or transmitted as electronic signals over a system bus or network. An identified module may, for instance, comprise one or more physical or logical blocks of computer instructions, which may be organized as an object, procedure, function, or the like.
[0037] Nevertheless, the identified modules need not be located together, but may comprise disparate instructions stored in different locations, which together implement the described functionality of the module. Indeed, a module may comprise a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices.
[0038] As used herein, the term executable code, or merely “executable,” is intended to include any type of computer instruction and computer executable code that may be located within a memory device and/or transmitted as electronic signals over a system bus or network. An identified module of executable code may, for instance, comprise one or more physical or logical blocks of computer instructions which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be located together, but may comprise disparate instructions stored in different locations which together comprise the module and achieve the purpose stated for the module. Indeed, an executable may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices.
[0039] Similarly, operational data may be identified and illustrated herein within modules, and may be embodied in any suitable form and organized within any suitable type of data structure to be used, produced, or operated on during execution of an executable. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may at least partially exist merely as electronic signals on a system bus or network.
[0040] FIG. 1 is a schematic block diagram illustrating a computer system 10 in which a plurality of modules may be hosted on one or more computer workstations 12 connected via a network 14 . The network 14 may comprise a wide area network (WAN) or local area network (LAN) and may also comprise an interconnected system of networks, one particular example of which is the Internet.
[0041] A typical computer workstation 12 may include a central processing unit (CPU) 16 . The CPU 16 may be operably connected to one or more memory devices 18 . The memory devices 18 are depicted as including a non-volatile storage device 20 (such as a hard disk drive or CD-ROM drive), a read-only memory (ROM) 22 , and a random access memory (RAM) 24 .
[0042] Preferably, the computer workstation 12 operates under the control of an operating system (OS) 25 , such as OS/2®, WINDOWS NT®, WINDOWS®, UNIX®, and the like. In one embodiment, the OS 25 may provide a graphical user interface (GUI) to enable the user to visually interact with the modules of the present invention. The OS 25 may be loaded from the non-volatile storage device 20 into the RAM 24 at the time the workstation 12 is booted.
[0043] The workstation 12 may also include one or more input devices 26 , such as a mouse 50 and/or a keyboard 52 ( FIG. 2 ), for receiving inputs from a user. Similarly, one or more output devices 28 , such as a monitor and/or a printer, may be provided within, or be accessible from, the workstation 12 .
[0044] A network interface 30 , such as an Ethernet adapter, may be provided for coupling the workstation 12 to the network 14 . In one embodiment, the workstations 12 may be coupled to the network 14 via a distributed remote data architecture (DRDA). Where the network 14 is remote from the workstation 12 , the network interface 30 may comprise a modem, and may connect to the network 14 through a local access line, such as a telephone line.
[0045] Within any given workstation 12 , a system bus 32 may operably interconnect the CPU 16 , the memory devices 18 , the input devices 26 , the output devices 28 , the network interface 30 , and one or more additional ports 34 , such as parallel and serial ports.
[0046] The system bus 32 and a network backbone 36 may be regarded as data carriers. Accordingly, the system bus 32 and the network backbone 36 may be embodied in numerous configurations, such as wire and/or fiber optic lines, as well as electromagnetic channels using visible light, infrared, and radio frequencies.
[0047] In general, the network 14 may comprise a single local area network (LAN), a wide area network (WAN), several adjoining networks, an Intranet, or, as in the manner depicted, a system of interconnected networks such as the Internet 40 . The individual workstations 12 may communicate with each-other over the backbone 36 and/or over the Internet 40 using various communication techniques.
[0048] For instance, different communication protocols, e.g., ISO/OSI, IPX, TCP/IP, may be used within the network 14 . In the case of the Internet 40 , however, a layered communications protocol (i.e. TCP/IP) generally best enables communications between the differing networks 14 and workstations 12 .
[0049] The workstations 12 may be coupled via the network 14 to application servers 42 , and/or other resources or peripherals 44 , such as scanners, printers, digital cameras, fax machines, and the like. External networks may be coupled to the network 14 through a router 38 and/or through the Internet 40 .
[0050] Referring now to FIG. 2 , the computer system 10 is part of a calling system 11 for customer contacting. The term customer, as used herein throughout, may be any type of contact that may be the object of a phone call either initiated or received by the computer system 10 . A user or sales agent may wear a headset 60 which includes an earpiece 62 for receiving audio inputs from a contact. A microphone 64 may be provided for providing audio outputs to the contact from the agent. A signal processor 70 is connected to the earpiece 62 by means of a speaker outline 66 . The signal processor 70 is also connected to the microphone 64 , which may also be connected to the headset 60 , by means of a microphone in line 68 .
[0051] The signal processor 70 may be connected to a sound card 80 by means of input lines 76 and output lines 78 . It will be appreciated that the signal processor 70 may be part of the computer system 10 . In this embodiment, the signal processor may interact via the busline 32 . The sound card 80 is connected via the busline 32 to the CPU 16 and to output devices 28 including a script player 81 . The sound card 80 is capable of outputting scripted voice waveforms over a telephone system 73 to the contact. It will be appreciated that the sound card 80 together with the processor 16 act as a player 81 . In other embodiments, the player 80 may be a script player 81 which may be a standalone module or device.
[0052] The sound card 80 or player 81 may be configured to provide an input to the signal processor 70 over a bus line 76 , 78 effective to render an output therefrom to the contact having a signal-to-noise ratio substantially the same as the signal-to-noise ratio of the output device 64 .
[0053] The signal processor 70 may include an impedance matching device 72 which may be connected to the phone system 73 and consequently to a potential customer's telephone 74 . The impedance matching device 72 may be integral with the signal processor 70 or may be a stand-alone device. The signal processor 70 , together with the impedance matching device 72 , are configured to provide a normalized signal selected from one of the output device 68 and the sound card 80 or player 81 . The signal processor 70 and the impedance matching device 72 are further configured to substantially match the signal-to-noise ratio of an output thereof, independent from the input thereto. Accordingly, the signal processor 70 and/or the impedance matching device 72 may normalize a first voice waveform received from the output device 64 and a second voice waveform received from the sound card 80 so that the source of these voice waveforms is substantially indistinguishable to the contact over the phone system 73 .
[0054] Thus, the present invention allows the transparent interleaving of live voice and prerecorded script by the agent. The transparent interleaving is further accomplished because the bandwidth of the data leaving the signal processor 70 and impedance matching device 72 is greater than the bandwidth of the phone system 73 , or an individual phone line that is part of the phone system 73 . A normal phone line band width is between about 200 Hz and 6,000 Hz. The output from the system 10 in one embodiment of the present invention is delivered at a band width approaching 20,000 Hz. By sending the recorded voice and the live voice through the same output, namely the signal processor 70 and impendence matching device 72 , at a higher band width than the phone, a natural filtering occurs making the two sounds indistinguishable when the scripts are recorded at a high sampling rate. The customer being called cannot tell the difference between the agent's voice and the pre-recorded script that an agent may decide to play.
[0055] The transparency between the output delivery of the live voice and prerecorded script to the contact is also accomplished because the prerecorded scripts are recorded at a high sampling rate. In one preferred embodiment, the sampling rate of recording is approximately 44,100. It will be appreciated by those of skill in the art that this is higher than typical phone recording sampling rates.
[0056] The signal processor 70 interacts with the computer's memory 18 , which in a preferred embodiment, contains an integration module 82 and a script module 84 , which are executable on the processor 16 . As will be discussed in greater detail below, this hardware and software configuration allows a human agent or the program itself to execute an interaction protocol to create interaction with a contact or potential customer. The hardware and software of the this system 11 allows the sales agent or computer to initiate the call and selectively interleave responses from the agent and a recorded script.
[0057] Referring now to FIG. 3 , the integration module 82 includes a voice transition module 86 for allowing the user to transition between live voices, a script branching a hierarchy, and various interjections. As will be discussed in greater detail below, the voice transition module 86 includes graphics and executable files for easy user navigation.
[0058] The integration module 82 may contain a database module 88 for storing and retrieving data. In one embodiment, the database module 88 includes database records 90 , a database engine 92 , and database indices 94 . The database engine 92 may access data 93 and a schema 95 that are part of the database records 90 . Examples of data may include call records 93 or prospect records 93 . The integration module 82 also includes a database interface module 96 and statistical abstracts 98 for ease in interfacing with the database engine 92 and records 90 . The database module 88 of the present invention may include database indices 94 that allow you to parse through database records 90 looking for specific information. The agent of user may selectively create or identify countless indices 94 to facilitate the convenient retrieval of data. It will be appreciated that the database engine 92 and records 90 may be standalone standardized database products known in the industry such as those made by Cybase® or Oracle®.
[0059] A statistical analysis engine 99 may operate in the background to access the database engine 92 and provide analysis of the database records 90 . The statistical analysis engine 99 along with the database engine 92 may be programmed, or accessed manually, to update and generate reports, or retrieve information on customer profiles, purchasing habits, purchaser demographics, product popularity, and other commercially valuable information. This information may be utilized to help the user or agent know which calls to make.
[0060] The database module 89 is also configured to maintain a history of any prerecorded scripts played by the system 11 . It will be appreciated that this will help determine or confirm what was represented to the contact by the sales agent or user.
[0061] Accordingly, the database module 88 of the system 11 allows for the automatic or manual update of a contact or customer file. The database module 88 allows the user, either manually or automatically, to keep and update a customer profile. The database module 88 also provides data storage and retrieval capabilities that allow the history of scripts to be recorded and archived for possible future reference.
[0062] The integration module 82 may contain a telephone interface module 100 which allows the system 10 of the present invention to interface with the telephone system 73 . The telephone interface module 100 allows a human agent or a computer dialer to initiate a call to a contact. In one embodiment, the telephone interface module 100 may go into the statistical abstracts 98 , for example and request data 99 such as all of the contact information on people who buy from a particular store, or who have bought something within the last 90 days and have incomes over $50,000. The telephone interface module 100 may go through the demographic data or customer profile data stored in the database module 88 . The telephone interface module 100 may then take the statistical abstract 98 data and initiate the call for the agent. In another embodiment, the telephone interface module 100 may present the agent with a menu of various options from which to choose including phone numbers of various contacts. The agent may then initiate the call or have the telephone interface module 100 make the call.
[0063] The present invention also includes a commercial transaction module 110 which in one embodiment, contains a credit card input 112 , a validation 114 , and a product input 116 . The commercial transaction module 110 allows the system 10 to validate contact sales information. The commercial transaction module 110 does all the credit card readings. The commercial transaction module may utilize the credit card input 112 and a validation 114 to determine whether the credit card has expired. The commercial transaction module 110 may also double check the information that an agent enters against stored information. The commercial transaction module 110 may also use the product input 116 to track and record product purchases. The product data may be sent to a manufacturer or distributor for shipment. It will be readily appreciated by those of skill in the art that credit data may be included as data 93 in the database records 90 including, user ID, credit card number, expiration date, and credit history verification.
[0064] The integration module 82 also includes an administration module 120 which may have a login 122 , a user security 124 , and preferences 126 . The login 122 may query a user for identification information which may include a user name and password. The user security 124 may be configured to conduct security checks. Thus, the administration module 120 may require customer authorization before the agent can access the content of the system or any system displays. The user security 124 module may administer the access to sensitive information such as credit card numbers, social security numbers, personal telephone numbers, passwords, keys, and the like. In this manner, the contact has less anxiety in given up certain information during the call. The administration module 120 is further configured to store system preferences 126 such as logins, agent names, times, dates, passwords, and the like.
[0065] Referring now to FIGS. 3 and 4 , the voice transition module 86 may cue up a script by means of a script menu display module 170 . The script menu display module 170 may display script data 172 on the monitor 53 . By clicking on the data 172 , the users may launch an executable file 174 for the selected script. The voice transition module 86 also includes an interjection menu display module 175 like the script menu display module 170 . The interjection menu display module 175 may display interjection script data 177 on the monitor 53 which when clicked or selected, launches an executable 179 for playing the interjection script. As discussed in greater detail below, the script menu display module 170 poses closed-ended questions, while the interjection display module selectively interjects statements by the human agent or user. The interjections may be selectively chosen from the human agent's or user's voice, and a recorded voice waveform. Accordingly the integration module 82 allows a user to select and present content to a contact.
[0066] The voice transition module 86 may also include a screen graphics display module 176 . The screen graphics display module 176 may interact with graphics files 177 , to facilitate the display of scripts or interjections on the screen for the user to select. The graphics display module 176 makes the program user friendly. The screen graphics display module 176 , together with the graphics files 177 , may produce images on the screen, prompts, reminders, borders, and a graphical presentations that can be navigated by the agent using a mouse 50 .
[0067] The voice transition module 86 also includes a navigation module 184 for negotiating between scripted responses to a contact. The navigation module 184 is responsible for interacting between the monitor 53 and the mouse 50 and the agent. The navigation module 184 allows the script menu display module 170 to have executable files 185 associated with data 187 on the screen to allow the agent to point and click with the mouse 50 or use a keyboard 52 to navigate between screens.
[0068] The voice transition module 86 of the integration module 82 may include a mode module 180 with various mode sections 182 . The mode module 180 , allows the agent to select between different modes 182 , including, live voice, script menu, or an interjection menu in order to interact with a contact. The mode module 180 switches hardware, so that the system is taking the data from different places in the program or voice input. As will be discussed in greater detail below, the selected script data 172 or interjection data 177 is played to the contact as recorded waveforms which may be preferably selected from computer generated wave files, audio recordings, synthesized voice, and actual voice.
[0069] In one embodiment, the microphone 64 may be on all the time with the volume turned down when the mode module 180 is in the script or interjection mode. In another embodiment, the microphone 64 is turned off during script or interjection mode and back on during live voice mode. In still another embodiment, one mode signal is simply overridden by another signal when the mode changes. The mode module 180 is what transitions the electronic switch around without sounding anything to the customer. Thus, in live voice, a user or the system does not have any clicks or pauses or transitional changes in pitch.
[0070] Referring now to FIG. 5 , when the agent determines to play scripted questions 190 , the script module menu 84 turns on the script player 81 . The script module 84 feeds the start of a scripted question 190 or an interjection 192 to the script player 81 for playing. The mode module 180 ( FIG. 4 ) turns on the script player 81 . When the system 10 receives an interrupt signal back from the script player 81 , the system 10 may perform a live voice transition back to the microphone 64 unless there is another scripted questions 190 or interjection 192 selected. If so, the mode module 180 transfers control of the program to the script player 81 for playing of the next recorded data 190 , 192 . The scripted questions 190 are prerecorded as a series of questions with a finite number of possible answers. When the first question is asked, the agent may select one of the known possible answers by clicking on the graphically displayed answer. This launches the next scripted question 190 which also has a known number of answers, the selection of which by the agent will launch the playing of the next scripted question 190 . The location of the various scripted questions 190 may be displayed in a script tree 150 which can be navigated by a mouse 50 , keyboard 52 , or other input device such as a touchpad, voice recognition software, and the like. At any time, the agent may interject with an interjection statement 192 such as “yes,” “no,” “uh huh,” laughter, and the like. The user may also select a scripted ending statement 194 such as “thanks for purchasing our product,” or a description of the product selected by the contact. Accordingly, the system 11 is configured to allow the agent or user to selectively provide prerecorded waveforms in the form of scripted dialog.
[0071] Referring now to FIG. 6 , a user interface 200 displays various options for the user. A first or any subsequent scripted question 190 is displayed. In conjunction with the scripted question, a number of corresponding possible answers 196 are displayed. Interjection scripts 192 are displayed should the user wish to interject into the series of questions and answers statements. Control options 202 allow the user to switch from scripted statements to live voice and back again. Navigational options 198 may also be displayed to move through hierarchical layers in a menu organization.
[0072] Referring now to FIG. 7 , a flow diagram of a method of the present invention is shown. The user may execute an interaction series 230 for executing a call to a contact. The user may then select and present content 232 to the contact. The content 232 , this may be in the form of a question having a finite number, or closed set, of answers. The user may then listen to a response 234 and decide whether to intervene 236 in the call. If the user does decide on intervention, he may decide 238 to create and deliver a personal live-voice response 240 or select and play one of number of scripted responses 242 . The user then listens to the response 234 and again decides whether to intervene 236 in the call. If the user does not decide to intervene, the user may decide to select and play another scripted response 244 , which starts the process over. The user may also decide to end the call 246 by live voice or by playing a standard ending script.
[0073] The method for customer contacting may start by providing an integrated system for interaction with a contact. The interaction is selectable from between human and computer delivery. The user may execute an interaction protocol to create an interaction with the contact. The call may then be initiated by the user or computer, for example by means of a dialing system, and the user may selectively interleave responses from a human agent and a recorded script.
[0074] The recorded script may include recorded data effective to control a computer for generating a human-sounding voice waveform. The recorded script is selected from computer-generated wave files, audio recordings, and synthesized voice. The recorded script may also a voice waveform created independently from the human agent. The voice waveform may also be an audio track of a voice response recorded by a voice actor.
[0075] Executing an interaction series or protocol 230 may include logging on by an agent. Executing an interaction series or protocol 230 may also include selecting a contact type. This may done according to available demographic data or referral data. The method may also include validating sales information. This may or may not be included as part of executing an interaction series 230 . Validating may be done by human agent or a computer dialing system. The method may also include updating a customer file based sales decisions or information gathered during the phone call.
[0076] A history of recorded and played scripts may be kept in the computer's memory 18 . This history may be recalled for a variety of reasons, including to verify what the user or agent claims was said to the contact or to contradict what a contact claims he or she was told by the agent. The history of the scripts played is quite similar to a recording of the entire conversation, given that particular scripts are linked to a finite range of answers given by the contact. Thus, a user of the system, in many instances, can recall both sides of a conversation between the agent and the contact.
[0077] The step of interleaving responses to the contact from either the agent or the computer includes listening by the human agent to a response from the contact 234 . Based on what is said or not said, the agent may select and present content to the contact 234 . Presenting content may be by posing a question to the contact which corresponds to a particular answer given by the agent. The answer may have been anticipated and displayed on the agent's computer screen. By clicking on the answer displayed on the screen, the computer launches the playing of the next script, which is a logical progression of the conversation or presentation of prior scripts.
[0078] At any time, the agent may decide to intervene 236 in the logical progression of the branching script. The agent may decide to play interjection script that is conversational in nature. For example, if the contact does not give a clear response, then the agent may not be able click on one of a predetermined number of answers associated with the scripted question asked. In this case, the agent may decide to intervene in the logical presentation of scripted questions and answers and play an interjection script 242 such as “I′m sorry, could you repeat that.” Once a clear answer is given, the agent may again go back to the script tree by clicking on the answer given by the contact which will launch the playing of the next script in the progression. The agent may also decide to intervene 236 with a live voice response 240 .
[0079] At any time during the playing of scripts or the presentation of live voice input, the agent may selectively decide to end the call 244 . This may be accomplished by playing an ending script such as, “How many videos would you like to order,” or “I′m sorry you're not interested, but have a nice evening.” The agent may also decide to end the call with live voice. The program is then ended.
[0080] The present invention may be embodied in other specific forms without departing from its scope or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.
[0081] From the above discussion, it will be appreciated that the present invention provides a client-initiated program and method of using same for providing outgoing calls. The invention may provide human voice or pre-recorded scripts that are flexible in the way content is presented and easily negotiable. The present invention also provides a program that allows for live validation of sale information (i.e. credit card information, etc.) and allows the operator to maintain and update a customer profile. The system and method of the present invention also allows the program to keep an historical record of which pre-recorded tracks were played by the sales agent and in what order. Thus, customer-alleged promises statements by the sales agent can be verified or denied with a tangible record. The system of the present invention provides for the seamless and transparent integration of an agent's live voice with a prerecorded voice by someone other than the agent.
[0082] The present invention may be embodied in other specific forms without departing from its structures, methods, or other essential characteristics as broadly described herein and claimed hereinafter. The described embodiments are to be considered in all respects only as illustrative, and not restrictive. The scope of the invention is, therefore, indicated by the appended claims, rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. | A system allows an agent to manage an interaction between the agent and a contact using a computer system. The agent may use the computer system to selectively interleave pre-recorded script segments that are part of a planned informational dialog with pre-recorded script interjections such that the selective playing of scripts or script segments mimics conversion between actual persons. | 7 |
CROSS REFERENCES TO RELATED APPLICATIONS
None.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is for a brush wear adjustment system and method, and in particular relates to a brush wear adjustment system for use in a street sweeping vehicle.
2. Description of the Prior Art
Rotary brushes utilized in street sweepers generally are mounted to the chassis of a truck or other suitable vehicle or structure. Normal wear and tear of a rotary brush during the sweeping mode results in worn rotary brush bristles the lengths of which are continually reduced due to abrasive qualities of the roadway with normal usage. The axle of the rotary brush is often secured between opposing pivot arms which gravitationally and automatically adjust in vertical fashion about pivot points to suitably contact the roadway and to compensate for the reduction in bristle length. As the bristle length is reduced, efficiency and effectiveness of the sweeping operation is increasingly degraded. Effective sweeping is predicated partially on the speed of the bristle tip, and is also predicted partially by the pressure of the bristles exerted downwardly to meet the roadway. A new rotary brush has long bristles which produces the highest bristle tip speed, and a well worn rotary brush has short bristles which produces a significantly slower and less effective bristle tip speed for the same rotary brush rate of rotation, thereby resulting in poorer and less effective sweeping. As the bristles wear, the rotary brush exhibits less control by gravitational downward force, thereby causing a lighter impingement with the roadway. Truck sweeper operators have lacked displays indicating brush wear which can be conveniently read in the control cab of a street sweeper. What is needed is a system which compensates for the degraded sweeping effectiveness and efficiency caused by continually shortening of the bristles of a rotary brush and which also displays brush wear. Such a system to provide consistent sweeping performance by increasing RPM of the rotary broom and/or adjusting the down pressure of the rotary broom is provided for by the present invention and method.
SUMMARY OF THE INVENTION
The general purpose of the present invention is to provide a brush wear adjustment system and method.
As used herein, a road sweeper is any kind of surface sweeper, including, among others, streets, roads, factory floors, and the like.
According to one embodiment of the present invention, there is provided a brush wear adjustment system and method, including a mounting surface, an optional protective enclosure, a retainer bracket, a position sensor secured to the mounting surface, a lever arm secured to and extending from the position sensor, a return spring mounted between the optional protective enclosure or other suitable location on the sweeper truck chassis and the lever arm, a linkage secured on one end to the outboard end of the lever arm and on the other end to an adjustable clevis, a linkage bracket connected to the lower end of the adjustable clevis, an electro-hydraulic controller, and a hydraulic metering valve. The hydraulic valve connects to a hydraulic rotary brush motor. Although hydraulic devices are shown and described, other devices utilizing other methods of propulsion for speed control such as, but not limited to, electric motors, rheostats, voltage controls, electronic control and the like can be utilized without departing from the apparent scope hereof.
The components of the invention are mounted to and about the chassis and other components of a sweeper truck or other such suitable vehicle or device. The position sensor and the connected lever arm are mounted to a mounting surface provided on a fixed portion of the sweeper chassis or optionally provided on an optional protective enclosure, and the linkage bracket secures to a pivoted support arm at a location between a pivot point and the corresponding rotary brush mount. The linkage attaches to and extends generally and substantially between the fixed portion of the sweeper chassis in communication with one of the pivoted support arms where displacement of the pivoted support arm is sensed by the position sensor via the interconnecting linkage. Information regarding the position of the pivoted support arm, and thus the length of the bristles, is sensed by the position sensor and sent by an interconnecting electrical cable to the electro-hydraulic controller which determines the proper and required rotary brush speed for efficient and effective sweeping by the ever shortening bristles. The position sensor also relays information to a readout display which can be located in the operating cab of the sweeper truck to indicate bristle wear. A hydraulic metering valve is actuated accordingly by the electro-hydraulic controller to increase the rotational speed of the hydraulic rotary brush motor to the required rotational speed. Aggressiveness of the sweep can be influenced by hydraulically operated cables attached to the pivoted support arms which support the rotary brush.
In another embodiment of the invention, a manual system, may be employed where sensor 16 is eliminated, and the speed controller for controlling the rotation rate of the rotary brush is provided with a manual input setting determined by a simple visual inspection of the remaining brush bristles, which may be color coded, or in the alternative a window may be provided with indicia relative to the remaining brush bristle length. In turn, this setting may be provide as an input to a controller for controlling brush rotation rate or brush position or both in accordance with a predetermined relationship to the visual inspection of the brush bristle length.
While the present invention has been particularly shown and described with reference to the accompanying figures, it will be understood, however, that other modifications thereto are of course possible, all of which are intended to be within the true spirit and scope of the present invention. Various changes in form and detail may be made therein without departing from the true spirit and scope of the invention as defined by the appended claims.
More specifically, position sensor 16 is intended to provide an output signal indicative of remaining brush bristle length on the brush. Brush diameter or radius is, of course, related to brush bristle length. Likewise, brush weight is indicative of bristle length since as the bristles wear, the brush weight decreases. Thus, sensor 16 represents any type of sensor which may provide an output signal indicative of the quantity intended to be sensed, i.e., bristle length, for ultimately controlling either the rotation rate of the rotary brush and/or the pressure of the brush against the surface intended to be swept in order to achieve consistent sweeping performance of a road sweeper or the like. Accordingly, sensor 16 may be implemented by a wide array of sensors including proximity sensors, optical sensors, and weight sensors depending upon the selected control scheme in accordance with the principles of the present invention, all of which are intended to be within the spirit and scope of the present invention.
Further, the most simplest form of the present invention is an open loop control system for setting the rotation rate of the rotary brush or brush position or both in response to the sensed value of the remaining bristles on the rotary brush. However, a closed loop control system may also be employed having more or less advantages. Further, the control system of the present invention may be complex employing an algorithmic relation of bristle length to the controlled parameter, i.e., brush rotation rate or position, or may simply be based on a selected or predetermined look up table relating the parameter intended to be controlled in response to the sensed value of the remaining bristles on the rotary brush, all of which are intended to be within the spirit and scope of the present invention. It should also be recognized that the brush wear system of the present invention may be implemented by a wide array of analog and digital techniques, including microprocessors, computers, software and firmware, and the like, and either being part of a sole system or part of a more complex controller having many more functions.
Although depicted in the drawings is a particular rotary brush positioning system employing linkages, cables, hydraulic pumps, electro-hydraulic controllers, and hydraulic motors, and the like, others are of course possible. For example, the rotary brush system may be implement by electrical linear actuators or linear hydraulic actuators as opposed to pivotal arrangements shown in the drawings, and the like, all of which are intended to be within the true spirit and scope of the present invention.
A significant aspect and feature of the present invention is a brush wear adjustment system which provides for consistent sweeping performance by adjustment of rotary brush speed and/or rotary brush down pressure.
A significant aspect and feature of the present invention is a brush wear adjustment system which accommodates the constant and increasing shortening of bristles.
Another significant aspect and feature of the present invention is a brush wear adjustment system which senses data relating to the rotating brush bristle length.
Another significant aspect and feature of the present invention is a brush wear adjustment system which increases the rotational rate of a rotating brush to maintain the tip speed of a bristle.
Yet another significant aspect and feature of the present invention is a brush wear adjustment system incorporating the use of a position sensor to determine vertical displacement of a rotary brush.
A further significant aspect and feature of the present invention is a brush wear adjustment system incorporating the use of an electro-hydraulic controller to determine required rotary brush speed.
A still further significant aspect and feature of the present invention is a brush wear adjustment system incorporating a metering valve controlled by an electro-hydraulic controller to vary the rotary brush speed.
Yet another significant aspect and feature of the present invention is the use of the invention as a brush wear indicator where the wear or the amount of bristle remaining can be viewed on a swivelable readout display in the operator cab of a sweeper truck.
Having thus described embodiments of the present invention and enumerated several significant aspects and features thereof, it is the principal object of the present invention to provide a brush wear adjustment system, and method for use in a road sweeper or other suitable device.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects of the present invention and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein:
FIG. 1 illustrates a brush wear adjustment system, the present invention, connected to components external to the invention;
FIG. 2 illustrates an exploded view of the components of the invention mounted to a mounting surface;
FIG. 3 illustrates an isometric view of the combined retainer bracket, bearing and lever arm in distanced alignment with the position sensor;
FIG. 4 illustrates an exploded top view in partial cutaway of the relationship of the mounting surface, the optional protective enclosure, the position sensor, the retainer bracket, the bearing and the lever arm;
FIG. 5 illustrates a top view in partial cutaway of the relationship of the mounting surface, the optional protective enclosure, the position sensor, the retainer bracket, the bearing and the lever arm;
FIG. 6 illustrates in part the mode of operation of the invention in use where the brush wear adjustment system is incorporated into use with and mounted to a chassis and to a pivoted rotary brush support arm of a street sweeper; and,
FIG. 7 illustrates in part the mode of operation of the invention in use where the brush wear adjustment system is incorporated into use with and mounted to a chassis and to a pivoted rotary brush support arm of a street sweeper.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a brush wear adjustment system 10 , the present invention, connected to components external to the invention the external components of which include a hydraulic reservoir and a hydraulic rotary brush motor, and a hydraulic pump. The invention mounts, in part, to a mounting surface 11 which can be almost any suitably located stable and planar surface of varying size, such as a nearby truck chassis member. The typically utilized mounting surface 11 could also be a separate planar structure, such as shown herein, and could also include an optional protective enclosure 12 , if desired. The mounting surface 11 serves as a direct or indirect mount for components including a retainer bracket 14 , a position sensor 16 , a lever arm 18 , and a return spring 20 . One end of a linkage 22 connects to the outwardly located end of the lever arm 18 and the other end of the linkage 22 communicatively connects to a linkage bracket 24 via an adjustable clevis 26 . The linkage 22 can be a rod, a chain, a cable or other suitable device which can connect the outwardly located end of the lever arm 18 to the linkage bracket 24 via the adjustable clevis 26 . An electrical cable 28 connects electrically between the position sensor 16 and an electro-hydraulic controller 30 to relay electrical positional information relating to the angular displacement of the lever arm 18 from a datum as measured by the position sensor 16 . Such electrical positional information is incorporated to control the speed of the rotary brush 76 and to provide information for a brush length readout display 33 .
Electrical positional information is sent via the electrical cable 28 to the electro-hydraulic controller 30 which contains suitable circuitry or computational devices such as, but not limited to, a micro-computer, as well as other required controlling devices. The output of the electro-hydraulic controller 30 controls a metering valve 32 or other such suitable apparatus which under commands can variably deliver hydraulic fluid from a hydraulic reservoir and hydraulic pump under the correct pressure and suitable flow to the hydraulic rotary brush motor of a sweeper. In the alternative and in lieu of the metering valve 32 , the electro-hydraulic controller 30 could control a variable displacement hydraulic pump to power the hydraulic rotary brush motor; or, the electro-hydraulic controller 30 could directly control a variable speed rotary brush motor.
Electrical positional information as provided by the position sensor 16 is sent via an electrical cable 29 to a computer 31 which drives the readout display 33 to provide bristle length information to either the driver or driver's assistant in the truck sweeper cab. The readout display 33 can be swivel mounted for viewing by the driver or driver's assistant.
FIG. 2 illustrates an exploded view of the components of the invention mounted to a mounting surface 11 . The optional protective enclosure 12 having a plurality of planar sides 12 a– 12 n can mount to one side of the mounting surface 11 . The mounting surface 11 is conveniently shown as a member which could be sized for mating with the optional protective enclosure 12 , but could be any suitable road sweeper panel or structure member extending beyond the optional protective enclosure. The position sensor 16 includes horizontally oriented mounting slots 34 and 36 centered about a rotationally positionable shaft 38 having a receptor slot 40 . The rotationally positionable shaft 38 extends slightly beyond the inwardly located planar surface 16 a of the position sensor 16 . The position sensor 16 mounts to the back side of the mounting surface 11 and is mounted thereto where the extended end of the rotationally positionable shaft 38 accommodatingly aligns with a body hole 42 on the mounting surface 11 . Opposing arcuate slots 44 and 46 center about the body hole 42 , as well as aligning respectively with the mounting slots 34 and 36 of the position sensor 16 . Machine screws 48 and 50 extend through arcuate slots 44 and 46 and the mounting slots 34 and 36 , as well as slots 14 a and 14 b of the retainer bracket 14 , to engage lock nuts 52 and 54 . The entire position sensor 16 can be rotated about the rotationally positionable shaft 38 and be positionally rotated to the extent allowed by the relationship of the machine screws 48 and 50 engaging the arcuate slots 44 and 46 and the mounting slots 34 and 36 . Such rotational positioning allows for operational calibration of the brush wear system 10 . The lever arm 18 includes a shaft 56 fixedly extending through one end. The inwardly positioned end of the shaft 56 includes opposing flattened surfaces 56 a and 56 b to allow accommodation by the receptor slot 40 of the rotationally positionable shaft 38 . The opposing end of the lever arm 18 includes a spring engagement hole 60 and a cable connector engagement hole 62 . The return spring 20 connects between the lever arm spring engagement hole 60 and an anchoring hole 66 located on or near the mounting surface 11 . For purposes of example and demonstration, the anchoring hole 66 is shown on a bracket 67 . A bearing 68 is accommodated by and fits over the outwardly facing portion of the shaft 56 to serve as an interface between the shaft 56 and a bearing mount 70 located on the retainer bracket 14 . The retainer bracket 14 includes an outwardly located panel 14 c upon which the bearing mount 70 is located, upper and lower offset panels 14 d and 14 e extending offsettingly at an angle from the upper and lower portions of the outwardly located panel 14 c , and inwardly located slot panels 14 f and 14 g , including slots 14 a and 14 b , extending vertically downwardly and upwardly from the offset panels 14 d and 14 e , respectively. Offsetting the slots 14 a and 14 b allows free and clear access of the machine screws 48 and 50 to the arcuate slots 44 and 46 and the mounting slots 34 and 36 previously described.
FIG. 3 is an isometric view of the combined retainer bracket 14 , bearing 68 and lever arm 18 in distanced alignment with the position sensor 16 . Shown in particular is the relationship of the lever arm 18 in close juxtaposition with the outwardly located panel 14 c and being distanced therefrom, as shown in FIG. 5 , by the planar portion 68 a of the bearing 68 disposed therebetween.
FIG. 4 is an exploded top view in partial cutaway of the relationship of the mounting surface 11 , the optional protective enclosure 12 , the position sensor 16 , the retainer bracket 14 , the bearing 68 and the lever arm 18 .
FIG. 5 is a top view in partial cutaway of the relationship of the mounting surface 11 , the optional protective enclosure 12 , the position sensor 16 , the retainer bracket 14 , the bearing 68 and the lever arm 18 .
Mode of Operation
FIGS. 6 and 7 illustrate the mode of operation of the invention in use where the brush wear adjustment system 10 is incorporated into use with and mounted to a chassis 72 and to a pivoted rotary brush support arm 74 of a street sweeper, where the rotary brush is in contact with a roadway 84 . A powered rotary brush 76 attaches to the rearward end of the pivoted rotary brush support arm 74 and to the rearward end of a corresponding similarly constructed and configured opposing pivoted rotary brush support arm (not shown), but referred to as pivoted rotary brush support arm 74 a . The powered rotary brush 76 and pivoted support arm 74 are supported by a pivot 78 and by a bracket 80 which is variably supported by a hydraulically operated positioning cable (not shown). Typically, positioning cables are attached to a torque tube which is influenced by a hydraulic cylinder to provide supportive lift for the pivoted rotary brush support arms 74 and 74 a and the corresponding pivoted rotary brush support arm and for the rotary brush 76 to share the loading of the bristles 82 . Such an arrangement influences the amount of pressure applied between the bristles 82 of the rotary brush 76 and the roadway 84 . The aggressiveness, i.e., the amount of rotary brush down pressure of the sweep can be determined by the operator. The amount of pivoted rotary brush support arm and rotary brush support provided can be controlled by the operator to apply the correct amount of down pressure required for an individual sweeping job. Light debris, such as dust or dry leaves, would require light bristle pressure where a greater portion of the pivoted rotary brush support arm weight and rotary brush weight is provided by the hydraulically operated positioning cables where other heavier debris, such as wet leaves, dirt, small stones, gravel or the like, require heavy bristle pressure to achieve suitable sweeping where a lesser portion of the pivoted rotary brush support arm weight and rotary brush weight is provided by the hydraulically operated positioning cables. The linkage 22 at the end of the lever arm 18 connects to the pivoted support arm 74 to monitor the angular displacement of the pivoted support arm 74 where such displacement is determined by the length of the bristles 82 .
FIG. 6 depicts a rotary brush 76 having full length bristles 82 yet unaffected by roadway abrasion and wear encountered during normal sweeping along the roadway 84 . Commencing with sweeping operations with bristles 82 being of full length, the pivoted support arm 74 is positioned as shown where the pivoted rotary brush support arm 74 is at or near the upwardmost angle of travel with respect to the full length of the bristles 82 . Accordingly, the lever arm 18 of the brush wear adjustment system 10 is positioned at or near the upwardmost angle of lever arm 18 travel and preferably the linkage 22 is tensioned slightly against the force of the return spring 20 to provide an accurate and responsive datum information for positional processing by the electro-hydraulic controller 30 . The appropriate and lower relative rotational speed of the rotary brush 76 having full length bristles 82 as sensed by the position sensor 16 and attached lever arm 18 is determined by the electro-hydraulic controller 30 . Such determination requires that the metering valve 32 or other such suitable device causes the hydraulic pressure from a hydraulic reservoir and hydraulic pump to be regulated or otherwise controlled to provide the proper and suitable rotational speed of the rotary brush 76 .
FIG. 7 depicts a rotary brush 76 having shortened bristles, herein designated as shortened bristles 82 a , affected by roadway abrasion and wear encountered during normal and continued sweeping along the roadway 84 . During sweeping operations with the worn and shortened bristles 82 a , the pivoted support arm 74 being angularly displaced is positioned as shown where the pivoted rotary brush support arm 74 is at or near the lowermost angle of travel with respect to the shortened length of the bristles 82 a . Accordingly, the lever arm 18 of the brush wear adjustment system 10 is also positioned at or near the lowermost angle of lever arm 18 travel. Information regarding the shortened length bristles 82 a of the rotary brush 76 as sensed by the position sensor 16 and attached lever arm 18 is delivered to the electro-hydraulic controller 30 and an appropriate rotary brush 76 speed is determined. Such determination requires that the metering valve 32 or other such suitable device causes the hydraulic pressure from a hydraulic reservoir and hydraulic pump to be accommodatingly regulated to provide the proper and increased and suitable rotational speed of the rotary brush 76 . Such increasing of the rotary brush 76 rotational speed and of the attached shortened bristles 82 a increases the tip speed of the shortened bristles 82 a to compensate for the degraded sweeping effectiveness and efficiency caused by continually shortening of the bristles 82 of the rotary brush 76 to promote consistent sweeping performances. During the sweeping operation and as the bristles 82 decrease in length, the speed of the rotary brush 76 is automatically increased at a suitable rate as sensed by the position sensor 16 which is rotated by angular displacement of the lever arm 18 . Positional information from the position indicator 16 is incorporated by the electro-hydraulic controller 30 at all times to produce a suitable rotary brush 76 rotational rate.
Various modifications can be made to the present invention without departing from the apparent scope hereof.
Brush Wear Adjustment System and Method
Parts List
10
brush wear adjustment system
11
mounting surface
12
optional protective enclosure
12a–n
planar sides
14
retainer bracket
14a–b
slots
14c
outwardly located panel
14d–e
offset panels
14f–g
slot panels
16
position sensor
16a
planar surface
18
lever arm
20
return spring
22
linkage
24
linkage bracket
26
adjustable clevis
28
electrical cable
29
electrical cable
30
electro-hydraulic controller
31
computer
32
metering valve
33
readout display
34
mounting slot
36
mounting slot
38
rotationally positionable shaft
40
receptor slot
42
body hole
44
arcuate slot
46
arcuate slot
48
machine screw
50
machine screw
52
lock nut
54
lock nut
56
shaft
56a–b
flattened surfaces
60
spring engagement hole
62
cable connector engagement hole
66
anchoring hole
67
bracket
68
bearing
68a
planar portion
70
bearing mount
72
chassis
74
pivoted support arm
76
rotary brush
78
pivot
80
bracket
82
bristles
82a
shortened bristles
84
roadway | A brush wear adjustment system for use in a powered street sweeper to provide for consistent sweeping performance where wear of rotary brush bristles is constantly sensed and the rotational speed of the rotary brush is automatically increased to maintain a desired bristle tip speed to maintain desirable sweeping attributes. Rotary brush support arm angular displacement is monitored in order for an electro-hydraulic controller to influence rotational speed of the rotary brush and to provide a readout relative to bristle length. | 4 |
BACKGROUND
[0001] Water is a building's worst enemy. Whether it comes from precipitation, groundwater, or condensation, water can, over time, cause mold and mildew, rotting of wood structures, corrosion of metals, separation of paint from surfaces, spalling of masonry and concrete, and health problems for building occupants. Moisture problems are a principal factor limiting the useful service life of a building.
[0002] Groundwater can be shunted away by drains and water barriers; buildings can be sheltered from rainwater by roofs and walls that shed water; but condensation is particularly insidious because it originates within the building itself.
[0003] Whenever a building is heated or cooled, a danger exists that moisture-laden air may travel from the warmer side of an exterior wall to the colder side, condensing when it reaches any surface colder than its dewpoint.
[0004] FIG. 1 illustrates the condensation problem in a heating season 102 . Moisture may be added to the air 101 inside a building by various sources, such as tub baths and showers, respiration and perspiration of pets and humans, humidifiers, cooking, dishwashing, internal clothes dryer venting, floor mopping, houseplants, and gas range pilot lights. A chimney effect within the building may cause a chronic exfiltration of air 103 from the upper part of the structure, through cracks and other imperfections in the wall. A temperature gradient exists within the wall, from the warm inside wall 105 through the insulation 100 to the cold outside wall 106 . When the airflow reaches a surface that is below the air's dewpoint, condensation 104 occurs. The condensation can continue over long periods of time, resulting in a significant accumulation of liquid water within the wall assembly.
[0005] FIG. 2 illustrates the basic method that has historically been used to combat winter condensation. The basic rule is, “Put a vapor barrier on the warm side of the wall.” In FIG. 2 , as in FIG. 1 , a temperature gradient exists in winter 202 from the warm inside wall 205 through the insulation 200 to the cold outside wall 206 . In FIG. 2 , a vapor barrier 204 has been added, which prevents the humid inside air 203 from traveling into the wall. As a result the dewpoint of the air within the wall cavity is equal to the lower dewpoint of the dry outside air. Therefore no condensation occurs within the wall. Humid interior air 201 is in contact with the interior side of the vapor barrier, but the vapor barrier is warm because it is on the warm side of the wall. In particular, it is warmer than the dewpoint of the humid interior air, and so no condensation forms on the vapor barrier. The vapor barrier does not have to be perfect to be effective. It is sufficient if the vapor barrier is significantly less gas-permeable than the wall structures between the vapor barrier and the outside. When this requirement is met, the wall will dry to the outside, and so the dewpoint of the air within the wall cavity will be approximately the same as the dewpoint of the dry outside air. No condensation will form.
[0006] FIG. 3 depicts the problem for a building that is air-conditioned in a cooling season 302 . The temperature gradient now runs in the opposite direction, from a warm outside wall 306 through the insulation 300 to a cold inside wall. Air 301 inside the building is dehumidified as well as cooled. A reverse chimney effect induces an infiltration 303 of warm humid air in the upper part of the structure, from the outside to the inside. When this air contacts materials colder than its dewpoint, condensation 304 accumulates.
[0007] FIG. 4 illustrates the basic method that is recommended for warm climates, to combat this condensation. Now the exterior temperature is higher, so the vapor barrier 404 is placed on the outside. The vapor barrier prevents high-dewpoint exterior air from traveling through the wall. As a result the dewpoint of the air within the wall is equal to the lower dewpoint of the dry inside air. Therefore no condensation occurs within the wall. Humid exterior air 403 is in contact with the vapor barrier 404 , but does not condense because the vapor barrier is on the warmer side of the wall, and is at a higher temperature than the dewpoint of the outside air. Again, the vapor barrier does not have to be perfect, only significantly less gas-permeable than the structures of the wall between it and the interior.
[0008] The solution for a heated building is FIG. 2 . The solution for an air-conditioned building is FIG. 4 . But what about the usual case, where the building is heated at various times, and cooled at various other times? One possibility that presents itself (U.S. Pat. No. 5,027,572) is to put vapor barriers on both the inside and outside of the wall. But this does not solve the problem because the dewpoint of the air between the two barriers will be at some value intermediate between the dewpoint of the outside air and the dewpoint of the interior air, depending on the relative amount of leakage on the two sides. If either side of the wall is below this value, condensation will form on that side. Merely placing a vapor barrier on the warm side is not sufficient. It is also necessary that, at the same time that the vapor barrier is blocking humid air on the warm side, any moisture within the wall must be allowed to leave toward the dry side. Otherwise moisture can be trapped between the two vapor barriers, leading to condensation. In other words, the air inside the wall must be the air from the dry side, with its lower dewpoint. During the heating season this is the exterior air, and during the cooling season it is the interior air.
[0009] Before the advent of air conditioning, buildings only had to cope with being heated. Any exterior wall that had more ventilation to the exterior than to the interior, whether by design or by accident, was safe from condensation. Most buildings today in temperate zones will be cooled in the summer and heated in the winter, and so will face the quandary described above. Indeed, buildings that are retrofitted with air conditioning commonly develop condensation problems as a result. Buildings that have survived for decades, or even centuries, may be destroyed when air conditioning is installed, by rotting of their structural wood members.
[0010] Various other proposals have been made to deal with the problem. US-2003/0205129, US-2004/0211315, and U.S. Pat. No. 6,793,713 propose periodically placing desiccant within the insulation cavity. US-2010/0233460 and US-2010/0229498 propose ventilating an insulating cavity with manually operated valves. US-2007/0094964, US-2007/0084139, and U.S. Pat. No. 7,247,090 describe systems with a dehumidifier that forces dehumidified air into the insulating cavity.
[0011] What is needed is an inexpensive insulating system that automatically, throughout all seasons, ventilates to the colder side, while blocking ventilation to the warmer side.
[0012] A component, that will be used in the current invention, and that is well known in the art, is a one-way valve that operates with low-pressure differential between inlet and outlet. U.S. Pat. No. 8,464,715 describes one-way valves that are used in non-rebreathing facemasks. US-3993096 describes a one-way valve operated by air pressure, used in air conditioners. U.S. Pat. No. 4,565,214 describes a flapper check valve that is operated by a low-pressure differential. U.S. Pat. No. 6,210,266 describes a flap valve for pressure relief in an automobile passenger compartment.
[0013] The requirements for a one-way valve in the current invention are that it be durable, and operate in response to a low-pressure differential between its inlet and outlet. It need not perfectly seal against wrong-way flow, but only restrict wrong-way flow to be significantly lower than right-way flow. It does not need to have a large flow rate, only a flow rate that is larger than whatever leakage exists in the vapor barriers of the current invention.
[0014] FIGS. 5 , 6 , 7 , and 8 depict a low-pressure differential one-way valve 500 , as is well known in the art. 502 is the inlet, and 501 is the outlet. A lightweight and flexible but strong membrane 504 in the shape of a disc is secured at its periphery 505 to be held above a barrier 506 with inlet holes 507 . When inlet 502 pressure is higher than outlet 501 pressure ( FIGS. 5 and 6 ), a flow 503 is established through the inlet holes 507 and out through the outlet 501 . The schematic symbol depicting the flow condition is shown in FIG. 6 . When inlet 502 pressure is lower than outlet 501 pressure ( FIGS. 7 and 8 ), the membrane 504 presses against the barrier 506 , blocking the holes 507 and preventing backflow ( 703 ). The schematic symbol depicting the non-flow condition is shown in FIG. 8 .
SUMMARY
[0015] The air in an insulating cavity is at a temperature intermediate between the temperatures of the interior and exterior of a building. This fact is exploited to induce a chimney effect in the insulating cavity, relative to the colder of the two adjacent temperatures. In the heating season, ventilation takes place between the insulating cavity and the exterior but is blocked between the cavity and the interior, thus replacing any humid air with dry outside air. In the air-conditioning season, ventilation takes place between the insulating cavity and the interior but is blocked between the cavity and the exterior, thus replacing any humid air with dry inside air. In effect, the system obeys the rule of thumb “Put the vapor barrier on the warm side of the wall,” in both heating and air-conditioning seasons.
[0016] The flows of air are very small, because they only need to be larger than any leakage in the vapor barriers situated on the exterior and interior sides of the cavities. In particular, the flows of air do not cause any significant reduction of the insulating ability of the system.
[0017] Four one-way valves regulate the flows. Each valve opens and closes exclusively in response to differential pressure between its inlet and outlet. The system is entirely automatic, requires no human control or regulation, and no external power source other than the temperature differential between the inside and the outside of the building. The only moving parts of the system are the flap membranes inside the one-way valves.
[0018] By always ensuring that the air inside the cavity comes from the drier side, condensation is prevented.
DRAWINGS
Figures
[0019] FIG. 1 (Prior Art) shows the problem of moisture condensation during a heating season.
[0020] FIG. 2 (Prior Art) shows the usual method of preventing moisture condensation during a heating season.
[0021] FIG. 3 (Prior Art) shows the problem of moisture condensation during an air-conditioning season.
[0022] FIG. 4 (Prior Art) shows the usual method of preventing moisture condensation during an air-conditioning season.
[0023] FIG. 5 (Prior Art) shows the usual direction of airflow in a one-way valve.
[0024] FIG. 6 (Prior Art) schematically shows the usual direction of airflow in a one-way valve.
[0025] FIG. 7 (Prior Art) shows how a one-way valve stops backflow.
[0026] FIG. 8 (Prior Art) schematically shows a one-way valve stopping backflow.
[0027] FIG. 9 shows the operation of the current invention in a heating season.
[0028] FIG. 10 shows the operation of the current invention in an air-conditioning season.
DRAWINGS
Reference Numerals
[0000]
100 —fill insulation
101 —building interior
102 —exterior of building in heating season
103 —exfiltration of air from interior to exterior
104 —condensation where humid air touches material colder than air dewpoint
105 —interior wall
106 —exterior wall
200 —fill insulation
201 —building interior
202 —exterior of building in heating season
203 —exfiltration of air blocked by vapor barrier
204 —vapor barrier
205 —interior wall
206 —exterior wall
300 —fill insulation
301 —building interior
302 —exterior of building in air-conditioning season
303 —infiltration of air from exterior to interior
304 —condensation where humid air touches material colder than air dewpoint
305 —interior wall
306 —exterior wall
400 —fill insulation
401 —building interior
402 —exterior of building in air-conditioning season
403 —infiltration of air blocked by vapor barrier
404 —vapor barrier
405 —interior wall
406 —exterior wall
500 —one-way valve
501 —air outlet
502 —air inlet
503 —airflow
504 —membrane
505 —membrane securement
506 —barrier
507 —air holes
703 —blocked backflow
900 —fill insulation
901 —building interior
902 —building exterior in heating season
903 —upper interior one-way valve
904 —upper exterior one-way valve
905 —lower interior one-way valve
906 —lower exterior one-way valve
907 —interior wall with vapor barrier
908 —exterior wall with vapor barrier
909 —airflow into cavity from exterior
910 —airflow within cavity
911 —airflow from cavity to exterior
912 —blocked airflow between interior and cavity
913 —cavity
1002 —building exterior in air-conditioning season
1009 —airflow from building interior into cavity
1010 —airflow within cavity
1011 —airflow from cavity into building interior
1012 —blocked airflow between exterior and cavity
DETAILED DESCRIPTION
[0085] The function of the building insulation system is to minimize the flow of heat, without allowing condensation to form. FIG. 9 shows the system in operation during a heating season 902 , and FIG. 10 shows the system in operation during a cooling season 1002 . An insulating cavity 913 is interposed between the interior 901 of a building, and the exterior ( FIG. 9 902 or FIG. 10 1002 ). An optional insulating material 900 , such as fiberglass or cellulose, may be interposed between an inner wall 907 and an outer wall 908 . Both inner 907 and outer 908 walls are impermeable to gas, including water vapor. Four one-way valves 903 , 904 , 905 , and 906 control all airflow into and out of the cavity.
[0086] Situated at the top of the inner wall 907 is an upper interior one-way valve 903 that is configured to allow air 1011 to flow from the cavity 913 to the interior 901 , but not in the opposite direction.
[0087] Situated at the bottom of the inner wall 907 is a lower interior one-way valve 905 that is configured to allow air 1009 to flow from the interior 901 to the cavity 913 , but not in the opposite direction.
[0088] Situated at the top of the outer wall 908 is an upper exterior one-way valve 904 that is configured to allow air 911 to flow from the cavity 913 to the exterior 902 , but not in the opposite direction.
[0089] Situated at the bottom of the outer wall 908 is a lower exterior one-way valve 906 that is configured to allow air 909 to flow from the exterior 902 to the cavity 913 , but not in the opposite direction.
[0090] When the structure is being heated ( FIG. 9 ), the temperature in the interior of the building is higher than inside the cavity, which in turn is higher than the exterior. Thus a chimney effect is created within the cavity, relative to the exterior: the pressure at the top of the cavity is greater than the exterior pressure at the same height, and the pressure at the bottom of the cavity is less than the exterior pressure at the same height. Thus air flows from the exterior through the lower exterior one-way valve into the cavity, up the cavity, and out the upper exterior one-way valve to the outside. Any moist air inside the cavity is flushed out and replaced by dry exterior air. Meanwhile, because the temperature inside is greater than the temperature in the cavity, a potential chimney effect is created within the interior, relative to the cavity. However no flow of air takes place between the interior and the cavity, because the pressure at top of the interior is greater than the pressure at the same height within the cavity, and the pressure at the bottom of the interior is less than the pressure at the same height within the cavity. Thus the upper interior and lower interior valves block the flow of air between the interior and the cavity.
[0091] When the structure is being air-conditioned ( FIG. 10 ), the temperature in the interior of the building is lower than inside the cavity, which in turn is lower than the exterior. Thus a chimney effect is created within the cavity, relative to the interior: the pressure at the top of the cavity is greater than the interior pressure at the same height, and the pressure at the bottom of the cavity is less than the interior pressure at the same height. Thus air flows from the interior through the lower interior one-way valve into the cavity, up the cavity, and out the upper interior one-way valve to the interior. Any moist air inside the cavity is flushed out and replaced by dry interior air. Meanwhile, because the temperature in the exterior is greater than the temperature in the cavity, a potential chimney effect is created within the exterior, relative to the cavity. However no flow of air takes place between the exterior and the cavity, because the pressure at top of the exterior is greater than the pressure at the same height within the cavity, and the pressure at the bottom of the exterior is less than the pressure at the same height within the cavity. Thus the upper exterior and lower exterior valves block the flow of air between the interior and the cavity.
[0092] We see, then, that the system obeys the rule “Put a vapor barrier on the warm side of the wall,” in both heating and cooling seasons, while allowing the wall to dry out to the drier colder side. The air inside the wall cavity is always the air of the colder and drier side and thus has its lower dewpoint. Condensation is prevented during all seasons. | An exterior wall is kept free of moisture condensation in both heating and cooling seasons by four one-way valves that utilize pressure differentials of a chimney effect to ventilate the insulating cavity with air from the drier colder side, while maintaining a vapor barrier on the more humid warmer side. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of application Ser. No. 15/346,211, filed Nov. 8, 2016, entitled “Tower Support Structure”, which is a continuation of application Ser. No. 14/618,648, filed Feb. 10, 2015, now U.S. Pat. No. 9,499,954, issued Nov. 22, 2016, entitled “Tower Support Structure”, each of which is hereby fully incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention generally relates to towers such as communication towers, wind power towers and lighting towers. More particularly, the invention relates to a foundation or support structure for a tower.
BACKGROUND
[0003] Towers or other vertical supports are utilized to support many structures such as cell phone antennas, other broadcast antennas, lights, wind power turbines and many other appliances. Towers of any significant height and bearing any significant load must be attached to some form of foundation to keep the tower upright and to resist the forces of wind and weather.
[0004] In construction engineering, foundations and foundation designs can vary but commonly use poured concrete and reinforcing rods or reinforcing bars to form a heavy integral structure that is either buried or placed on the ground to support a structure such as a tower. However, the use of concrete foundations is not always convenient or even feasible.
[0005] In many of these cases, the use of a concrete foundation is not practical because of limited availability of concrete, long concrete casting and curing times, or the fact that concrete construction creates a large amount of construction waste. For example, materials used for concrete forms often cannot be reused and must be discarded.
[0006] Accordingly, there is still room for improvement in the arts related to tower installation and tower foundations.
SUMMARY
[0007] The present invention solves many of the above discussed problems by providing a structure that can be fully assembled and disassembled in a short period of time and that permits the utilization of local materials to provide ballast. The foundation structure of the present invention eliminates many of the issues typical to a standard foundation utilized for support structures such as communications towers.
[0008] Recent trends have demonstrated a need for temporary, quick to assemble and disassemble foundation on which to mount a tower. A need has also been recognized for a foundation having reduced environmental impact.
[0009] For example, after major natural disasters, such as earthquakes, typhoons, tornadoes and tsunamis, there is often a need to rapidly construct temporary structures for lighting, telecommunications and/or security applications. Often, it is necessary to locate these towers or structures in remote locations. Remote locations often have limited accessibility and complex or unfavorable terrain that may make it difficult to transport concrete to a foundation site. Further, the distance from a ready mix concrete plant may make it prohibitively expensive or prohibitively difficult to transport concrete to the construction site.
[0010] Even without considering natural disasters or other emergency needs to provide foundations for tower-like structures, growing telecommunications demand has created a need to construct or deploy more tower sites more quickly and thus has created a demand to expedite the process of building a tower site. Wind energy turbine towers are often located far from sources of concrete and may have limited accessibility as well as difficult terrain.
[0011] According to an example embodiment of the invention, a tower assembly includes a tower and a base assembly. The tower is generally conventional in structure and will not be described in detail here. The tower may be of a type used to support, for example, cell phone antennas, wind power equipment, lighting or weather monitoring equipment.
[0012] The base assembly generally includes a main pedestal support, bottom trays, side support panels, primary support beams and secondary support beams.
[0013] The main support pedestal is centrally located within the foundation and includes a vertical cylindrical or polygonal pipe structure having top and bottom plates secured thereto. The top and bottom plates are secured to the cylinder and extend out radially from the top and bottom of the cylinder or polygonal structure. The top plate presents multiple bolt holes typically uniformly spaced around the top plate and located outwardly from the circumference of the cylinder or polygonal tube. The main support pedestal also presents gussets radially disposed around an outer circumference thereof. The gussets are typically evenly spaced around the cylinder or polygonal tube and extend vertically from a top to a bottom of the tubular structure and are bounded by the top plate and the bottom plate.
[0014] The bottom trays are secured to the base of the main support pedestal and are arranged generally horizontally around the main support pedestal base. The bottom trays are formed of plates, typically having a polygonal geometry. According to an example embodiment of the invention, the bottom trays are generally trapezoidal in shape having a small end of the trapezoid located centrally and a large end located peripherally. The bottom trays are secured proximate an inner edge thereof to the main support pedestal and proximate an outer edge thereof to the side support panels.
[0015] According to an example embodiment of the invention, the side support panels are generally rectangular plate-like structures arranged vertically around an outer circumference of the foundation. The length of each rectangular side support panel is approximately equal to that of the side length of the long side of the bottom trays. The bottom trays are secured to the side support panels. Adjacent side support panels are secured together by a hinge-like connection and a hinge pin thus forming the outer perimeter of the base. The hinge-like connection generally includes mating hinge barrels on the edges of adjacent side support panels. Alternate hinge barrels are secured on each of the mating edges.
[0016] According to an example embodiment of the invention, the primary support beams form part of a truss-like support arm. Each primary support beam is secured to the gussets near the top of the main support pedestal. The primary support beams angle downward from near the top of the main support pedestal to the outside of the foundation to be secured with the side support panels and the bottom trays at a juncture thereof.
[0017] According to an example embodiment of the invention, a secondary support beam is secured at a first end to approximately the mid-point of the primary support beam and at a second end thereof to a top of a corresponding side support panel.
[0018] According to an example embodiment, the base assembly bottom support pallet is formed of the bottom trays. Generally, this forms a regular polygon for example, a regular hexagon assembled from an equal quantity of bottom support trays, side support panels, primary support beams and secondary support beams. In the case of hexagonal assembly, there is six of each of these structures. While the primary example discussed in this application is a hexagonal structure, it should be understood that the invention is not limited to hexagonal structures. The structures may for example be hexagonal, octagonal, decagonal, dodecagonal or tetradecagonal. That is structures according to the invention may have six, eight, ten twelve or fourteen sides or a larger number of sides depending upon the involvement. Embodiments having an odd number of sides are also contemplated.
[0019] According to an example embodiment of the invention, the main support pedestal, bottom trays and bottoms of side support panels are connected together by fasteners such as bolts. According to an example embodiment, the primary support beam extends outwardly along the bottom trays to the respective side support panels and is secured at both the connection between the bottom trays and the side support panels and at the gussets near the main support pedestal. This structural arrangement provides strength and rigidity of the connection between the main support pedestal and the bottom trays.
[0020] According to an example embodiment, the primary and secondary support beams may be formed, for example, from galvanized steel angle. The connection between the primary support beam and the foundation may be accomplished by fasteners such as bolts. The bottom trays and side support panels as well as a primary support beam may be secured by a single fastener.
[0021] The primary support beam may be secured to the gussets on the main support pedestal near the top flange also by a bolt or other fastener. The bottom side of each side support panel is secured to one of the vertical support bars of a bottom tray and to the other side support panels via a hinge-like connection. A pin is passed through hinge barrels of the hinge-like connection to hold each of the side support panels together with its adjacent side support panel. The pins are secured in place by an R-type stop pin at the bottom.
[0022] Once the base assembly is fully assembled it is filled with ballast. Examples of ballast that can be utilized include soil, gravel, bricks, concrete blocks and sand. Of course other ballast material may be used so long as the material is sufficiently dense to stabilize the base assembly. The use of local materials as ballast assists in reducing costs for installation.
[0023] Accordingly, a base assembly in accordance with the present invention may be utilized to replace a traditional concrete foundation used for installing self-supporting towers. The base assembly according to the present invention is easy to install, easy to handle and may be assembled and ready for use in a single day. This is a great advantage over concrete foundations which require significant curing times. The base assembly of the present invention may be used in multiple ways including in the ground, above the ground and may utilize many different types of ballast. The base assembly of the present invention can be disassembled and relocated and can be used for both short term and long term deployment.
[0024] The above summary is not intended to describe each illustrated embodiment or every implementation of the subject matter hereof. The figures and the detailed description that follow more particularly exemplify various embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Subject matter hereof may be more completely understood in consideration of the following detailed description of various embodiments in connection with the accompanying figures, in which:
[0026] FIG. 1 is a perspective view of a base assembly according to an example embodiment of the invention;
[0027] FIG. 2 is a perspective view of a main pedestal support according to an example embodiment of the invention;
[0028] FIG. 3 is a perspective view of a main pedestal support surrounded by six bottom trays according to an example embodiment of the invention;
[0029] FIG. 4 is a partially exploded perspective view of a main pedestal support, bottom trays and side support panels according to an example embodiment of the invention;
[0030] FIG. 5 is a perspective view of an assembled base assembly including a tower according to an example embodiment of the invention;
[0031] FIG. 6 is a plan view of a hexagonal tower base according to an example embodiment of the invention;
[0032] FIG. 7 is an elevational view of the base assembly of FIG. 6 ;
[0033] FIG. 8 is a plan view of an octagonal base assembly according to an example embodiment of the invention;
[0034] FIG. 9 is an elevational view of the base assembly of FIG. 8 ;
[0035] FIG. 10 is a plan view of a ten sided base assembly according to an example embodiment of the invention;
[0036] FIG. 11 is an elevation view of the base assembly of FIG. 10 ;
[0037] FIG. 12 is a plan view of a ten sided base assembly according to an example embodiment of the invention;
[0038] FIG. 13 is an elevational view of the base assembly of FIG. 12 ;
[0039] FIG. 14 is a plan view of a twelve sided base assembly according to an example embodiment of the invention;
[0040] FIG. 15 is an elevational view of the base assembly of FIG. 14 ;
[0041] FIG. 16 is a plan view of a fourteen sided base assembly according to an example embodiment of the invention; and
[0042] FIG. 17 is an elevational view of the base assembly of FIG. 16 .
[0043] While various embodiments are amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the claimed inventions to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the subject matter as defined by the claims.
DETAILED DESCRIPTION
[0044] Referring to FIGS. 1 and 5 , tower foundation 20 according to an example embodiment of the invention generally includes tower 22 and base assembly 24 . Tower 22 is generally conventional in design and can include a monopole tower such as those used to support cell phone transmission antennas, lights or wind power equipment.
[0045] Base assembly 24 is a generally basket-like or topless container structure. Base assembly 24 generally includes main pedestal support 26 , bottom trays 28 , side support panels 30 , primary support beams 32 and secondary support beams 34 . Main pedestal support 26 is centrally located and is surrounded by bottom trays 28 . In the depicted example embodiment, there are six bottom trays 28 and a generally hexagonal structure. However, this should not be considered limiting as various embodiments of the invention as depicted in FIGS. 6-16 may have other polygonal structures having anywhere between six to fourteen sides. Side support panels 30 are arranged around the perimeter of bottom trays 28 and are secured to one another and are also secured to primary support beams 32 and secondary support beams 34 . Primary support beams 32 extend generally from main pedestal support 26 to side support panels 30 . Secondary support beams 34 extend generally from primary support beams 32 to side support panels 30 .
[0046] Referring particularly to FIGS. 1 and 2 , main pedestal support 26 generally includes tubular member 36 , top flange 38 , bottom flange 40 and a plurality of longitudinal gussets 42 . The number of longitudinal gussets is equal to the number of bottom trays 28 , the number of side support panels 30 , the number of primary support beams 32 and the number of second support beams 34 according to the depicted example embodiment.
[0047] Tubular member 36 is conveniently formed of a steel tube having a cylindrical or polygonal cross-section. Tubular member 36 is conveniently formed of steel tube; however it may be formed of aluminum tube or another material of sufficient strength and rigidity. If tubular member 36 is polygonal in cross-section, it is convenient, according to an example embodiment, if the polygon has a number of sides equal to the number of longitudinal gussets 42 or multiple of the number of longitudinal gussets 42 .
[0048] Referring again to FIGS. 1, 2 and 3 , top flange 38 is secured to tubular member 36 , for example, by welding. Tower top flange 38 presents tower fastener holes 44 located regularly therein about its perimeter. Tower fastener holes 44 are conveniently located midway between adjacent longitudinal gussets 42 . This should not be considered limited however.
[0049] Referring to FIG. 1 , according to another embodiment, top flange 38 may include tower hinge extensions 46 supporting tower hinge tabs 48 . According to the depicted embodiment, tower hinge tabs 48 are pierced by hinge holes 50 . Tower hinge tabs are spaced to accommodate tower tabs (not depicted) on tower 22 .
[0050] Bottom flange 40 is located at an opposing end of tubular member 36 from top flange 38 . Bottom flange 40 is generally perpendicular to tubular member 36 and extends radially outward therefrom.
[0051] Referring particularly to FIG. 2 , longitudinal gussets 42 are evenly spaced about tubular member 36 and extend between top flange 38 and bottom flange 40 according to the depicted embodiment. Longitudinal gussets 42 may conveniently be formed of plate or sheet steel and present upper extension portion 52 , lower extension portion 54 and middle portion 56 . Upper extension portion 52 is joined to top flange 48 for example by welding. Lower extension portion 54 is joined to bottom flange 40 for example by welding. Upper extension portion 52 , lower extension portion 54 and middle portion 56 abut tubular member 36 and may be joined thereto for example by welding. Upper extension portion 52 is pierced by primary support fastener holes 58 . In the depicted embodiment, there are two primary support fastener holes 58 . However, there may be as few as 1 or more than 2 primary support fastener holes 58 .
[0052] Lower extension portion 54 is pierced by tray fastener holes 60 . In the depicted embodiment, there are two tray fastener holes 60 , however, this should not be considered limiting as there may be as few as one or more than two tray fastener holes 60 .
[0053] Top flange 38 and bottom flange 40 may conveniently be formed of steel plate or sheet. Longitudinal gussets 42 may also be conveniently formed of steel plate or sheet though other materials may be utilized as well so long as they have sufficient rigidity and strength.
[0054] Referring particularly to FIGS. 2, 6, 8, 10, 12, 14 and 16 , bottom trays 28 in the depicted embodiment are generally trapezoidal-shaped structures. Bottom trays 28 may be conveniently fabricated from sheet steel and steel angle, however, this should not be considered limiting as other materials may be utilized. Bottom trays 28 , according to the depicted embodiment, present inner edge 62 , outer edge 64 and side edges 66 . Inner edge 62 and outer edge 64 are generally parallel and inner edge 62 is shorter than outer edge 64 . Side edges 66 are angled relative to inner edge 62 and outer edge 64 .
[0055] Bottom trays 28 generally include base sheet 68 , optional inner edge angles (not shown), outer edge angles 72 , side edge angles 74 , central reinforcement beam 76 and perpendicular reinforcements 78 . Inner edge angles, if present, are secured to inner edge 62 of base sheet 68 for example by welding. Outer edge angles 72 are secured to outer edge 64 of base sheet 68 , for example, by welding. Side edge angles 74 are secured to side edges 66 of base sheet 68 , for example, by welding. Side edge angles 74 present adjacent panel fastener holes 80 . Side edge angles 74 are pierced by adjacent tray fastener holes 80 . Outer edge angles 72 are pierced by side panel fastener holes 82 .
[0056] Central reinforcement beam 76 extends generally radially through a center of base sheet 68 and extends from inner edge 62 to outer edge 64 . Central reinforcement beam 76 extends slightly beyond inner edge 62 and outer edge 64 . Central reinforcement beam 76 includes inner end 84 and outer end 86 . Inner end 84 is pierced by gusset fastener holes 88 . Outer end 86 is pierced by panel fastener holes 90 . Perpendicular reinforcements 78 extend in both directions between central reinforcement beam 76 and side edge angles 74 . Perpendicular reinforcements 78 are oriented generally parallel to inner edge angles, if present, and outer edge angles 72 in the depicted embodiment. Central reinforcement beams 76 and perpendicular reinforcements 78 are conveniently secured to base sheet 68 for example by welding.
[0057] Referring particularly to FIG. 4 , side support panels 30 are generally rectangular in structure and include side panel plate 92 , upper angle 94 , lower angle 96 , side angles 98 and vertical reinforcement 100 . Upper angle 94 is secured to side panel plate 92 at upper edge 102 . Lower angle 96 is secured to lower edge 104 of side panel plate 92 . Side angles 98 are secured to side edges 106 of side panel plate 92 . These structures may all be secured for example by welding.
[0058] Vertical reinforcements 100 extend generally vertically between upper angle 94 and lower angle 96 .
[0059] Upper angle 94 further includes central secondary support tab 108 pierced by fastener hole 110 .
[0060] Lower angle 96 also includes corner tabs 112 pierced by fastener hole 114 and central primary support tab 116 pierced by fastener hole 118 .
[0061] Side edges 106 also include hinge barrels 120 secured to an outer portion thereof. Hinge barrels 120 are sized and structured to receive hinge barrels pins 122 therethrough. Hinge barrel pins 122 are structured to accept R clip 124 at an end thereof.
[0062] Referring particularly to FIG. 1 , primary support beams 32 generally include inner end 126 , outer end 128 and central portion 130 . Inner end 126 is pierced by gusset fastener holes 132 . Outer end 128 is pierced by lower panel fastener holes 134 . Central portion 130 is pierced by central beam fastener holes 136 .
[0063] Secondary support beams 34 generally include inner end 138 and outer end 140 . Inner end 138 is pierced by primary support fastener holes 142 . Outer end 140 is pierced by panel fastener holes 144 .
[0064] Primary support beams 32 and secondary support beams 34 may be fabricated from steel angle or other sufficiently rigid material.
[0065] In operation, tower foundation 20 is placed on a prepared area. The prepared area is leveled prior to installation for example by placement of an aggregate and leveling the aggregate prior to installation.
[0066] Main pedestal support 26 is placed centrally on the leveled prepared area. Bottom trays 28 are positioned around main pedestal support 26 with inner end 84 of central reinforcement beam 76 located adjacent to lower extension portions 54 of longitudinal gussets 52 .
[0067] Once bottom trays 28 are all located, fasteners such as bolts (not shown) may be utilized to secure inner end 84 of central reinforcement beam 76 to lower extension portions 54 of longitudinal gussets 42 . Bottom trays 28 may be secured to each other by the application of fasteners through adjacent tray fastener holes 80 . Side support panels 30 are secured to bottom trays 28 by application of fasteners through outer edge angles 72 through corner tabs 112 . Side support panels 30 are secured to each other by aligning adjacent hinge barrels 120 and inserting hinge barrel pins 122 through hinge barrels 120 . Hinge barrel pins 122 are then secured by the application of R clips 124 at a lower end thereof. When all side support panels 30 are in place, primary support beams 32 are installed.
[0068] Primary support beams 32 are installed by coupling inner end 126 to upper extension portion 52 of longitudinal gussets 42 and outer end 128 to central primary support tab 116 at the lower edge of side support panels 30 . Secondary support beams 34 are secured at inner end 138 to central portion 130 of primary support beams 32 . Outer ends 140 of secondary support beams 34 are secured to central secondary support tab 108 of side support panels 30 . All fasteners are then secured tightened.
[0069] The interior of base assembly 24 is then filled with ballast such as soil, gravel, bricks, concrete blocks or other locally available ballast.
[0070] Tower 22 is then secured to main pedestal support 26 via top flange 38 . Tower 22 is typically secured to top flange 38 via bolts.
[0071] In the embodiment where tower hinge tabs 48 are present, tower hinge tabs 48 are secured to a base of tower 22 via similar tabs (not shown) on tower 22 . Tower 22 may then rotated from a horizontal position to a vertical position and secured by fasteners.
[0072] The present invention may be embodied in other specific forms without departing from the spirit of the essential attributes thereof; therefore, the illustrated embodiments should be considered in all respects as illustrative and not restrictive, reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention.
[0073] Various embodiments of systems, devices, and methods have been described herein. These embodiments are given only by way of example and are not intended to limit the scope of the claimed inventions. It should be appreciated, moreover, that the various features of the embodiments that have been described may be combined in various ways to produce numerous additional embodiments. Moreover, while various materials, dimensions, shapes, configurations and locations, etc. have been described for use with disclosed embodiments, others besides those disclosed may be utilized without exceeding the scope of the claimed inventions.
[0074] Persons of ordinary skill in the relevant arts will recognize that the subject matter hereof may comprise fewer features than illustrated in any individual embodiment described above. The embodiments described herein are not meant to be an exhaustive presentation of the ways in which the various features of the subject matter hereof may be combined. Accordingly, the embodiments are not mutually exclusive combinations of features; rather, the various embodiments can comprise a combination of different individual features selected from different individual embodiments, as understood by persons of ordinary skill in the art. Moreover, elements described with respect to one embodiment can be implemented in other embodiments even when not described in such embodiments unless otherwise noted.
[0075] Although a dependent claim may refer in the claims to a specific combination with one or more other claims, other embodiments can also include a combination of the dependent claim with the subject matter of each other dependent claim or a combination of one or more features with other dependent or independent claims. Such combinations are proposed herein unless it is stated that a specific combination is not intended.
[0076] Any incorporation by reference of documents above is limited such that no subject matter is incorporated that is contrary to the explicit disclosure herein. Any incorporation by reference of documents above is further limited such that no claims included in the documents are incorporated by reference herein. Any incorporation by reference of documents above is yet further limited such that any definitions provided in the documents are not incorporated by reference herein unless expressly included herein.
[0077] For purposes of interpreting the claims, it is expressly intended that the provisions of 35 U.S.C. §112(f) are not to be invoked unless the specific terms “means for” or “step for” are recited in a claim. | A foundation for a tower, the foundation including a main pedestal support structured to engage to a base of the tower. A floor structure surrounds and is secured to the main pedestal support. A wall structure surrounds the floor structure proximate a perimeter thereof, secured to the perimeter of the floor structure and extending upwardly from the floor structure. The main pedestal support is located generally centrally in the floor structure. | 4 |
TECHNICAL FIELD
This application relates to processing a wafer and, in particular, to a method and/or system for dicing a wafer from the back side thereof.
BACKGROUND INFORMATION
Integrated circuits (ICs) are generally fabricated in an array on or in a semiconductor substrate. For example, FIG. 1 is a perspective view of a typical semiconductor wafer 100 having a plurality of ICs 110 formed thereon. The ICs 110 are separated by dicing lines or streets 112 that form a lattice pattern on a top surface of the semiconductor wafer 100 .
The ICs 110 are singulated by mounting the back side of the semiconductor wafer 100 on a tape frame (not shown) and cutting along the streets 112 formed on the top surface of the semiconductor wafer 100 . Cutting is generally carried out by a cutting machine called a dicer that includes a chuck table for holding the semiconductor wafer 100 and a mechanical saw or laser for cutting the semiconductor wafer 100 . Mechanical saws generally include a rotary spindle and a cutting blade mounted on the spindle. The cutting blade may include, for example, a disk-like base and an annular cutting edge fitted to the outer peripheral portion of the side surface of the base. The cutting edge generally includes diamond abrasive grains.
The streets 112 are generally visible from the top side of the semiconductor wafer 100 . Thus, from the top side of the semiconductor wafer 100 , the mechanical saw or laser may be guided along the streets 112 to cut the semiconductor wafer 100 into individual ICs. The tape frame, also referred to as dicing tape, holds the ICs 110 in place during and after the dicing process. However, the top surface of the ICs 110 are left unprotected during the dicing process and may be damaged by the mechanical saw or laser. For example, metals, low-k dielectrics, or other materials formed in the streets 112 on the top surface of the semiconductor wafer 100 can damage the ICs 110 and/or the mechanical saw.
FIG. 2 is an enlarged top view of the semiconductor wafer 100 shown in FIG. 1 illustrating metal features 210 , 212 formed in the streets 112 on the top surface of the wafer. The metal features 210 , 212 may include, for example, coupons or test circuits used during the manufacturing process and sacrificed when the semiconductor wafer 100 is diced. A test circuit may include, for example, a metal pattern called a test element group (Teg) applied over the semiconductor substrate 100 . The metal features 210 , 212 tend to clog or otherwise damage diamond impregnated saws typically used in the dicing process. Mechanical sawing produces burrs because a Teg, for example, is generally made of a soft metal such as copper or the like. In addition, as thinner wafers are produced, mechanical saws cause more edge chipping. Thus, yield (e.g., the number of functioning ICs produced from the wafer) decreases.
Laser dicing can also damage the ICs 110 and reduce yield. Instead of using a traditional saw blade, a laser beam is focused onto the top surface of the semiconductor wafer 100 to thereby “cut” the semiconductor wafer 100 into the individual ICs 110 . The process of laser dicing generates excessive heat and debris. The heat can cause heat affected zones and recast oxide layers. Cracks may form in the heat affected zones and reduce the die break strength. Further, the debris produced by lasers is molten in one state and can be very difficult to remove. Sacrificial coatings can be used to protect the top surface of the ICs 110 from debris during laser dicing. The sacrificial coating must then be removed after the dicing process. Another process uses a water jet in conjunction with the laser. The water jet washes the debris away during the dicing process. However, sacrificial coatings and water jet or other cleaning processes add time and expense to the overall dicing process.
Therefore, a method of dicing finished semiconductor wafers that increases throughput and yield is desirable.
SUMMARY OF THE DISCLOSURE
The embodiments disclosed herein provide systems and methods for scribing a semiconductor wafer with reduced or no damage or debris to a top surface of the semiconductor wafer caused by the scribing process. The semiconductor wafer is scribed from a back side thereof. In one embodiment, the back side of the wafer is scribed following a back side grinding process but prior to removal of back side grinding tape. Thus, debris generated from the scribing process is prevented from being deposited on a top surface of the wafer.
Currently, wafers are diced from the top side primarily because the dicing lanes or streets are visible only from the top surface. Thus, a cutting tool (e.g., a laser or a saw) must be aligned to these cutting lanes or streets from the top side of the wafer. In one embodiment, an infrared light source is used to illuminate the wafer from the front side thereof to allow alignment of the cutting tool to the dicing lanes or streets from the back side of the wafer. Advantageously, dicing from the back side prevents or reduces chipping, cracking, and/or laser generated debris from depositing on the top surface of the wafer.
According to the foregoing, in one embodiment, a method is provided for cutting a semiconductor wafer having a plurality of integrated circuits formed on or in a top surface thereof. The integrated circuits are separated by one or more streets visible from the top surface of the semiconductor wafer. The method includes illuminating the top surface of the semiconductor wafer with a light. A portion of the light passes through the one or more streets to a bottom surface of the semiconductor wafer. The method also includes imaging the portion of the light passing from the bottom surface of the semiconductor wafer so as to determine a location of the one or more streets relative to the bottom surface of the semiconductor wafer. After the location of the streets are determined, a portion of the bottom surface of the semiconductor wafer is cut corresponding to the location of the one or more streets.
In another embodiment, a method of manufacturing integrated circuits is provided. The method includes forming multiple electronic circuit components on or in a top surface of a semiconductor wafer. The electronic circuit components are separated by one or more streets. The method also includes covering the electronic circuit components with a protective layer and removing a portion of the semiconductor wafer from a first bottom surface thereof to form a second bottom surface of the semiconductor wafer. The second bottom surface of the semiconductor wafer is then imaged to determine a location of the one or more streets relative to the second bottom surface. Then, a portion of the second bottom surface is cut corresponding to the location of the one or more streets.
In another embodiment, a system is provided for cutting integrated circuits. The system includes a light source configured to illuminate a top surface of a wafer, an imaging device configured to generate image data corresponding to light from the light source that passes from the top surface of the wafer to a bottom surface of the wafer, and a processor configured to process the image data so as to map a location of a cutting lane on the top surface of the wafer to the bottom surface of the wafer.
In another embodiment, a system is provided for cutting integrated circuits. The system includes means for mapping a location of a cutting lane along a surface of the wafer, the cutting lane not visible from the surface of the wafer, and means for cutting the surface of the substrate along a path corresponding to the cutting lane.
Additional aspects and advantages will be apparent from the following detailed description of preferred embodiments, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a typical semiconductor wafer having a plurality of ICs formed thereon.
FIG. 2 is an enlarged top view of the semiconductor wafer shown in FIG. 1 illustrating metal features formed in the streets on the top surface of the wafer.
FIG. 3 is a flowchart illustrating a process for manufacturing ICs according to an embodiment of the invention.
FIGS. 4A-4G are side view schematics of a portion of an exemplary semiconductor work piece that is thinned and cut according to the process shown in FIG. 3 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
To avoid cutting metal features (e.g., test circuits) or other materials such as low-k dielectrics formed on a top surface of a semiconductor wafer, certain embodiments disclosed herein provide systems and methods for cutting the back side of the semiconductor wafer. The back side of the semiconductor surface is also referred to herein as the “bottom” or “bottom surface” and is generally on an opposite surface from the front or top surface where ICs and dicing lines or streets are formed.
For convenience, the term cutting may be used generically to include trenching (cutting that does not penetrate the full depth of a target work piece) and throughcutting, which includes slicing (often associated with wafer row separation) or dicing (often associated with part singulation from wafer rows). Slicing and dicing may be used interchangeably in the context of this disclosure.
As discussed above, the streets are generally visible from the top surface of the semiconductor wafer. However, the streets are not visible from the back side of the semiconductor wafer. Thus, according to one embodiment, the top surface of the semiconductor wafer is illuminated with a wavelength of light that pass through the semiconductor wafer and be detected from the back side thereof. As discussed in detail below, in one embodiment, the light is provided by a diffuse infrared (IR) light source. The detected light is used to map the streets relative to the back side. The back side is then cut at locations corresponding to the mapped streets.
In one embodiment, the back side of the semiconductor wafer is cut as part of a wafer thinning process. To reduce the thickness of ICs, semiconductor wafers are thinned after device fabrication and before dicing for individual packaging. Back side grinding is a conventional method for reducing silicon wafers from their original thickness to a diminished thickness suitable for final packaging. Grinding the back surface of the semiconductor wafer is fast and produces good total thickness variation and surface finish. Reducing the thickness of the semiconductor wafer generally improves cooling of the device after packaging.
The process of thinning wafers is performed after the ICs have been formed on the top surface of the semiconductor wafer. Back side grinding tape is applied to the top surface of the semiconductor wafer to protect the ICs. The semiconductor wafer then goes into a grinding machine and the back surface is ground away until a desired thickness is achieved. In conventional processes, the back side grinding tape is then removed and the back surface of the semiconductor wafer is mounted on a tape frame. Thus, the top surface of the semiconductor wafer is exposed and cut using a mechanical saw or laser.
However, according to certain embodiments disclosed herein, the back side grinding tape is left in place over the top surface of the semiconductor wafer during the cutting process. Thus, after grinding the back side, the grinding tape acts as a dicing tape to protect and hold the ICs in place while the back side of the semiconductor surface is cut. After dicing, the individual ICs can then be peeled from the grinding tape for packaging. An artisan will recognize from the disclosure herein that an individual die picked from the grinding tape may need to be flipped before being placed for packaging. Because the grinding tape is not removed from the top surface and a dicing tape is not applied to the back side of the wafer before dicing, fewer steps are used in the overall IC fabrication process. Thus, throughput is increased. Further, cutting the back side of the semiconductor wafer reduces damage to the ICs and increases yield. In one embodiment, however, the back side of the semiconductor wafer is placed on a tape frame after cutting the backside of the semiconductor wafer. The grinding tape is then removed from the top surface of the semiconductor and the tape in the tape frame is stretched to allow picking and placing of an individual die. In such an embodiment, the individual die does not need to be flipped after being picked from the tape and before being placed for packaging.
Reference is now made to the figures in which like reference numerals refer to like elements. For clarity, the first digit of a reference numeral indicates the figure number in which the corresponding element is first used. In the following description, numerous specific details are provided for a thorough understanding of the embodiments of the invention. However, those skilled in the art will recognize that the invention can be practiced without one or more of the specific details, or with other methods, components, or materials. Further, in some cases, well-known structures, materials, or operations are not shown or described in detail in order to avoid obscuring aspects of the invention. Furthermore, the described features, structures or characteristics may be combined in any suitable manner in one or more embodiments.
FIG. 3 is a flowchart illustrating a process 300 for manufacturing ICs according to one embodiment. At a step 310 , the process 300 includes forming ICs on a top surface of a semiconductor wafer. The ICs include one or more layers formed using known semiconductor IC manufacturing processes. As discussed above with respect to FIG. 1 , the ICs are separated by streets that form a lattice pattern on the top surface of the wafer.
At a step 312 , a protective layer is formed over the ICs and the top surface of the wafer. In one embodiment, the protective layer includes conventional back side grinding tape. The protective layer is configured to protect the ICs during subsequent processing steps and to hold the ICs in place after the wafer is cut. At a step 314 , the wafer is thinned by grinding its bottom surface using, for example, a grinding machine.
After the bottom surface is ground away to a desired thickness, the protective layer, the ICs and the top surface of the wafer are illuminated, at a step 314 , with light configured to pass through the protective layer and the semiconductor wafer. Thus, the protective layer and the semiconductor wafer are at least partially transparent to the wavelength of the light. The wavelength is selected so as to provide the desired transparency while still providing sufficient resolution to detect the streets. The light is diffuse so as to flood a portion of the top surface within the field of view of an imaging device (discussed below). Further, the intensity of the light is configured to provide a sufficient number of photons in the flooded area so as to satisfy the sensitivity threshold of the imaging device.
At a step 318 , the light passing through the bottom surface of the wafer is detected using an imaging device. The imaging device may include, for example, a CCD or CMOS imager configured to detect the wavelength of the light. The field of view of the imaging device is set so as to provide sufficient resolution so as to detect the streets. In one embodiment, the field of view of the imaging device is substantially matched to the area illuminated by the light. To achieve the desired resolution, the field of view of the imaging device may be substantially less than the area of the bottom surface of the wafer. Thus, the imaging device is scanned across the bottom surface of the wafer and the scanned images are combined to generate the overall image.
At a step 320 , the detected light is used to map the street locations relative to the bottom surface of the wafer. In one embodiment, the street locations are mapped by imaging the bottom surface and using pattern recognition to determine which portions of the overall image correspond to an image of a street. In one embodiment, the pattern recognition includes techniques used to recognize patterns in aerial photographs. For example, a Hough transform technique may be used that determines whether line segments in different portions of the image are part of a longer straight line forming a street. In another embodiment, a user maps the street locations by visually locating the street locations on an image created by the imaging device and entering the street locations into a computer. The entered street locations are then used to generate a scribe map for subsequent cutting of the bottom surface of the wafer.
In a step 322 , the process includes cutting portions of the bottom surface of the wafer corresponding to the mapped street locations. The bottom surface may be cut with a mechanical saw or a laser. In certain embodiments, the semiconductor wafer is scribed without cutting all the way through the wafer so as to avoid contact between a mechanical saw blade and any test devices or other structures above the top surface of the wafer. Thus, damage to the ICs and/or the saw is eliminated or reduced during the dicing process. After scribing the back side of the wafer, the wafer can be broken or otherwise diced along the scribed lines and individual ICs can be removed from the back side grinding tape for packaging. An artisan will recognize from the disclosure herein that an individual die picked from the grinding tape may need to be flipped before being placed for packaging.
In one embodiment, the back side of the semiconductor wafer is placed on a tape frame after cutting the backside of the semiconductor wafer. The grinding tape is then removed from the top surface of the semiconductor and the tape in the tape frame is stretched to allow picking and placing of an individual die. In such an embodiment, the individual die does not need to be flipped after being picked from the tape and before being placed for packaging.
By way of example, FIGS. 4A-4G are side view schematics of a portion of an exemplary semiconductor work piece 400 that is thinned and cut according to the process 300 shown in FIG. 3 . The work piece 400 includes a silicon wafer 410 having a top surface 412 and a first bottom surface 414 . A plurality of layers 416 , 418 are formed on the top surface 412 . As an artisan will recognize, the layers 416 , 418 may include interconnect layers and insulation layers that form electronic circuitry. For example, the layers 416 , 418 may include materials such as Cu, Al, SiO 2 , SiN, fluorosilicated glass (FSG), organosilicated glass (OSG), SiOC, SiOCN, and other materials used in IC manufacture. For illustrative purposes, two layers 416 , 418 are shown. However, an artisan will recognize that fewer or more layers can be used for particular ICs.
As represented by dashed lines in FIG. 4A , in this example, a first IC area 420 and a second IC area 422 are formed in the layers 416 , 418 . The first IC area 420 and the second IC area 422 are separated from one another by a street 424 . Although not shown, metallic test structures, low-k dielectrics, or other materials may be formed in the street 424 . In one embodiment, the width of the street 424 (e.g., the distance between the first IC area 420 and the second IC area 422 ) is in a range between approximately 8 μm and approximately 12 μm. However, an artisan will recognize that the street 424 may have other widths. For example, in other embodiments, the width of the street 424 is in a range between approximately 12 μm and approximately 50 μm.
In the manufacturing stage shown in FIG. 4A , the silicon wafer 410 has a thickness (e.g., the distance between the top surface 412 and the first bottom surface 414 ) in a range between approximately 250 μm and approximately 1000 μm. As discussed above, to thin the silicon wafer 410 , the bottom surface 414 is ground until a desired thickness is reached.
As shown in FIG. 4B , grinding tape 426 is applied over the top surface 412 and the layers 416 , 418 The grinding tape 426 protects the first IC area 420 and the second IC area 422 while the silicon wafer is thinned by grinding the first bottom surface 414 using, for example, a grinding machine. The grinding tape 426 is transparent to infrared light. Suitable back side grinding tape is available from, for example, Furukawa Electric Co., LTD. of Tokyo, Japan, Lintec Corp. Advanced Materials Div. Of Tokyo, Japan, and Toyo Adtec Co., LTD. of Kamakura, Japan. In one embodiment, the grinding tape 426 is substantially transparent to infrared light with wavelengths ranging between approximately 1.2 μm and approximately 1.3 μm. As discussed below, the silicon wafer 410 is also substantially transparent to these wavelengths.
The first bottom surface 414 is ground until a desired reduced thickness (represented by dashed line 428 in FIG. 4B ) is achieved. As shown in FIGS. 4C-4G , the grinding process produces a second bottom surface 430 . After grinding, the silicon wafer has a reduced thickness in a range between approximately 50 μm and approximately 200 μm. If the top surface 412 and the second bottom surface 430 are substantially smooth, it is easier to image the street locations using infrared light. Thus, in certain embodiments, the grinding process is followed by additional processes known in the art to smooth the second bottom surface 430 .
After grinding the silicon wafer 410 to the desired thickness, the location of the street 424 is mapped with respect to the second bottom surface 430 so that the second bottom surface 430 can be scribed along the street 424 . As shown in FIG. 4C , an infrared light source 432 is configured to flood a portion of the grinding tape 426 , the layers 416 , 418 and the silicon wafer 410 with diffuse infrared light 434 . The light source 432 may include, for example, an infrared light-emitting diode (LED) configured to generate infrared light in a desired band. Although not shown, a filter may also be used to reduce the range of wavelengths produced by the light source 432 to the desired band.
The wavelength of the infrared light 434 is selected so as to provide sufficient transparency through the grinding tape 426 and the silicon wafer 410 . The silicon wafer 410 tends to absorb shorter wavelengths. However, longer wavelengths may reduce the resolution such that the street 424 is not detectable from the back side of the silicon wafer 410 . In one embodiment, the wavelength is in a range between approximately 1.2 μm and approximately 1.3 μm.
The intensity of the infrared light 434 is sufficient to be detectable by an imaging device 436 positioned on the opposite side of the silicon wafer 410 . The imaging device 436 may include a CCD or CMOS camera configured to detect the infrared light after it passes through the grinding tape 426 and the silicon wafer 430 . For example, the imaging device 436 may include a Germanium or InGaAs CCD. In one embodiment, the imaging device 436 comprises an Alpha NIR camera available from FLIR Systems, Indigo Operations of Goleta, Calif.
As shown in FIG. 4C , the imaging device 436 is in communication with a processor 438 , such as a microprocessor, a digital signal processor, or the like. The processor 438 controls the operation of the imaging device 436 . The processor 438 executes software stored in a storage device 442 so as to perform various tasks discussed herein such as scanning the second bottom surface 430 , generating image data, and processing the image data so as to map a location of the street 424 . The processor 438 may be in communication with a communication device 440 so as to send and/or receive image data and/or mapped street locations.
The field of view of the imaging device 436 is selected so as to provide sufficient resolution to detect the street and is matched to the area flooded by the infrared light 434 . In one embodiment, the imaging device 436 has a field of view in a range between approximately 450 μm and approximately 550 μm. As discussed above, the infrared light source 432 and the imaging device 436 may be scanned over the work piece 400 and the scanned images can be combined to generate an overall image of the infrared light 434 passing through the second bottom surface 430 . The overall image is used to map the location of the street 424 with respect to the second bottom surface 430 . As discussed above, pattern recognition such as a Hough transforms or another image processing technique is used in one embodiment to determine whether line segments in various portions of the overall image are part of a longer straight line of the street 424 . In another embodiment, a user maps the street locations by visually locating the street locations on an image created by the imaging device and entering the street locations into the processor 438 for storage in the storage device 442 . The stored street locations are then used to generate a scribe map for subsequent cutting of the bottom surface of the wafer.
After the location of the street 424 has been mapped with respect to the second bottom surface 430 , the second bottom surface 430 is cut along the street 424 . FIG. 4D illustrates a mechanical saw blade 444 cutting a kerf into the second bottom surface 430 in a location corresponding to the street 424 . An artisan will also recognize that a laser can be used instead of a saw to ablate the second bottom surface 430 of the silicon wafer 410 . However, if the laser cutting is performed while imaging is also performed, the image of the second bottom surface 430 may include speckles produced by the laser that may make it more difficult to determine the location of the street 424 . Thus, in applications where part of a wafer is imaged while another part of the wafer is cut, it is preferable to use a dicing saw. However, an artisan will recognize that image processing techniques can be used to remove speckles from the image to facilitate concurrent imaging and laser cutting. Further, in one embodiment, the location of the street 424 is mapped before the laser is activated. Thus, the image of the second bottom surface 430 does not include speckles produced by the laser. Once the street 424 is mapped, the location information is stored and the light source 432 is turned off. The second bottom surface 430 can then be cut by the laser along the street 424 .
During the cutting process, the grinding tape 426 remains over the layers 416 , 418 and the top surface 412 of the silicon wafer 410 so as to protect the IC areas 420 , 422 from debris. The grinding tape 426 also holds the work piece 400 in place during and after the cutting.
As shown in FIGS. 4D-4F , the second bottom surface 430 is scribed in certain embodiments so as to avoid contact between the saw blade 444 and any metallic test structures, low-k dielectric material, or other materials that may be located above the top surface 412 of the silicon wafer 410 in the area of the street 424 . Thus, damage to the IC areas 420 , 422 and/or the saw blade 444 is eliminated or reduced during the scribing process. The second bottom surface 430 may be scribed to different depths, depending on the application. For example, FIG. 4E illustrates a scribed portion 446 extending approximately half way between the second bottom surface 430 and the top surface 412 . As another example, FIG. 4F illustrates a scribed portion 448 extending substantially to the top surface 412 .
As shown in FIG. 4G , the first IC area 420 and the second IC area 422 can then be completely diced and removed from the grinding tape 426 for individual packaging. After scribing, the first IC area 420 and the second IC area 422 may be diced, for example, by breaking the silicon wafer 410 along the scribed lines. Thus, by detecting street locations with respect to the back side of the wafer 410 and cutting the back side of the wafer 410 along the street locations, debris and chipping in the first IC area 420 and the second IC area 422 can be reduced or eliminated.
It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. For example, the back side of the wafer can be cut without first thinning the wafer. As another example, other wafer materials besides silicon and other light sources with different wavelengths can be used. However, substrates such as ceramics or the like are generally non-homogeneous, making it more difficult to image light passing through them. Thus, while non-homogeneous wafer materials can be used, substantially homogenous materials such as silicon are preferred.
As yet another example, the grinding tape is not transparent to the light used for imaging. Rather, according to one embodiment, the grinding tape includes cut outs or transparent windows corresponding to the streets and/or street intersections. In such embodiments, illumination through the cut outs or windows is detected from the backside of the wafer to indicate the street locations. Thus, a cutting tool can then be aligned to the streets from the back side of the wafer.
The scope of the present invention should be determined only by the following claims. | Systems and methods for scribing a semiconductor wafer with reduced or no damage or debris to or on individual integrated circuits caused by the scribing process. The semiconductor wafer is scribed from a back side thereof. In one embodiment, the back side of the wafer is scribed following a back side grinding process but prior to removal of back side grinding tape. Thus, debris generated from the scribing process is prevented from being deposited on a top surface of the wafer. To determine the location of dicing lanes or streets relative to the back side of the wafer, the top side of the wafer is illuminated with a light configured to pass through the grinding tape and the wafer. The light is detected from the back side of the wafer, and the streets are mapped relative to the back side. The back side of the wafer is then cut with a saw or laser. | 1 |
CROSS REFERENCE TO PRIOR APPLICATIONS
This application is a U.S. National Phase application under 35 U.S.C. §371 of International Application No. PCT/EP2010/070056, filed on Dec. 17, 2010 and which claims benefit to German Patent Application No. 10 2010 006 023.2, filed on Jan. 27, 2010. The International Application was published in German on Aug. 4, 2011 as WO 2011/091909 A1 under PCT Article 21(2).
FIELD
The present invention relates to a sealing arrangement for a control device of an internal combustion engine, comprising a housing, a channel arranged in the housing and through which gas flows, a control member by which a gas flow in the channel can be controlled, a shaft on which the control member is arranged, bearings by means of which the shaft is supported in bearing bores in the housing, and a vent bore extending in the housing from an inner wall of the channel on an inlet side of the control member to a rear side, facing out from the channel, of the bearings arranged in the housing, and into the bearing bore.
BACKGROUND
Such sealing arrangements are used, for example, in control devices, such as exhaust gas recirculation flap valves, for controlling a recirculated exhaust gas flow in commercial vehicles, where large quantities of exhaust gas must be supplied to the engine in a precisely controlled manner. It is necessary here to prevent the intrusion of exhaust gas into the bearings and, further, to prevent the gas from flowing through the bearing bore out into the atmosphere.
DE 10 2006 054 041 B3 discloses an exhaust gas control device comprising a housing in which an exhaust gas recirculation channel is formed that is controlled by a flap. This flap is driven by an electric motor via a transmission unit and is arranged for rotation on a shaft that is supported in bearing bores formed in the housing defining the channel. In order to prevent the intrusion of exhaust gas, and thus soot, into the bearings, and to simultaneously prevent a leakage gas flow to the outside, the housing is provided with a bore leading from the front side of the flap out from the channel to the rear side of the bearing and into the bearing bore. A sealing flow thus prevails on the rear side of the bearing that leads to a pressure balance with the inside of the channel so that the exhaust gas flow is not drawn into the bearing. To the outside, sealing is provided by means of a sealing disc abutting against a step of the bearing bore. This sealing disc is pressed against the step of the bearing bore by means of a spring via a collar bush and a sliding bush arranged between the collar bush and the sealing disc. The sliding bush serves to reduce friction, whereas a radially directed escape of a leakage flow is supposed to be prevented by the sealing disc and an escape is intended to be realized in the axial direction along the shaft via the axial extension of the collar bush which therefore forms a very narrow and long gap with the shaft.
It has, however, been found that such a design is insufficient with respect to the leakage values. The necessity of precise manufacturing furthermore results in high production costs.
SUMMARY
An aspect of the present invention is to provide a sealing arrangement for a control device with which the leakage values can be further minimized or with which it is possible at least to obtain cost advantages and assembly facilitations, while the leakage values remain the same.
In an embodiment, the present invention provides a sealing arrangement for a control device of an internal combustion engine which includes a housing. A channel is formed in the housing. The channel is configured to have a gas flow therethrough. A control member is configured to control a flow of the gas in the channel. The control member is arranged on a shaft. A bearing is configured to support the shaft in a bearing bore of the housing. A vent bore extends in the housing from an inner wall of the channel on an inlet side of the control member to a rear side, facing outward from the channel, of the bearing arranged in the housing, and into the bearing bore. A first groove is formed in the shaft behind the bearing. The first groove is configured so as to be circumferential when seen from the channel. The first groove is surrounded radially by a sealing device which is configured to cooperate with the first groove.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is described in greater detail below on the basis of embodiments and of the drawings in which:
FIG. 1 shows a side elevational view of a sealing arrangement according to the present invention, illustrated in section;
FIG. 2 shows a side elevational view of a slightly modified form of the sealing arrangement of the present invention shown in FIG. 1 , illustrated in section;
FIG. 3 shows a side elevational view of an alternative sealing arrangement of the present invention, illustrated in section; and
FIG. 4 shows a side elevational view of a slightly modified form of the sealing arrangement of the present invention shown in FIG. 3 , illustrated in section.
DETAILED DESCRIPTION
By forming a circumferential groove on the shaft behind the bearing, seen from the channel, which grove is radially surrounded by a sealing means cooperating with the groove, the forming of turbulences in the groove or an improved sealing by the groove is achieved, the groove serving as a labyrinth.
In an embodiment of the present invention, the groove of the shaft can, for example, be arranged radially within a collar bush serving as a further sealing means and being arranged on the shaft. This results in the forming of turbulences in the groove, whereby the resistance against a further flow through the gap between the shaft and the collar bush is increased significantly.
In an embodiment of the present invention, the inner circumference of the collar bushing is provided with a groove. A second opposite turbulence is thereby obtained that again increases the resistance against a flow through the gap and thereby improves the sealing effect.
In an embodiment of the present invention, the groove closer to the bearing has a larger volume than the farther groove. Additional pressure reduction is thereby achieved so that the driving pressure gradient is minimized.
In an embodiment of the present invention, the groove in the collar bush can, for example, be closer to the bearing than the groove in the shaft. The same groove lengths and groove depths can thus be used.
In an embodiment of the present invention, the collar bush can, for example, be biased by a spring against a sliding disc arranged on the shaft, which abuts against the housing from outside. The friction occurring can thus be minimized. At the same time, the sliding disc serves as a sealing against a radially outward directed leakage flow.
In an embodiment of the present invention, a slit metal sealing ring is arranged in the shaft groove which serves as an additional sealing means. This sealing ring, known as a piston ring, can be manufactured at low cost and is simple to assemble. The sealing effect of such a slit metal sealing ring in a groove is very high.
In an embodiment of the present invention, the slit metal sealing ring can, for example, be biased against an inner circumferential wall of the bearing bore, whereby a sealing at the radially outer circumference of the slit metal sealing ring is provided in addition to the sealing of the radially inner portion that is sealed by the cooperation of the sealing ring and the groove.
In an embodiment of the present invention, the slit metal sealing ring is biased to axially abut against a shoulder serving as a stop formed in the bearing bore. This additionally prevents a flow around the outer circumference of the sealing ring since the radially outer portion of the sealing ring abuts against the housing in the axial and the radial direction.
In an embodiment of the present invention, the two ends of the slit metal sealing ring can, for example, abut in the axial direction. A leakage flow through the separating gap of the sealing ring is thereby reliably prevented.
The present sealing arrangement for a control device is characterized by a high degree of tightness. Leakage flows along the shaft are reliably avoided. This leads to a longer lifetime of the bearings and to a reduced soiling of the outer portion. At the same time, such an arrangement can be manufactured and assembled in a cost-effective manner.
Two embodiments of a sealing ring arrangement according to the present invention are illustrated in the Figures and will be described hereunder.
The sealing arrangement for a control device illustrated in FIG. 1 comprises a housing 2 defining a channel 4 in which a flap is arranged for rotation therein, the flap serving as a control member 6 for controlling the mass flow in the channel 4 and being mounted on a shaft 8 . The shaft 8 extends from one wall of the housing 2 , in which a first bearing bore is arranged, to an opposite wall in which a further bearing bore 10 is arranged, the Figures respectively illustrating only the bearing bore 10 through which the shaft extends outward to a non-illustrated actuator unit.
A bearing 12 is arranged in the bearing bore 10 , which bearing surrounds the shaft 8 and by which the shaft 8 is supported in the bearing bore 10 . Upstream of the shaft 8 , seen in the flow direction, a vent bore 14 is formed that extends from an inner wall 16 of the channel 4 through the housing 2 up to a rear side 18 of the bearing 12 and into the bearing bore 10 . The gas present at the rear side 18 acts as a sealing gas. A pressure drop across the bearing 12 , i.e., a pressure difference between the channel 4 and the outer portion, is thereby prevented so that the entraining of dirt from the channel 4 into the bearing 12 is reduced, whereby the lifetime of the bearing 12 is extended.
In order to also prevent the sealing gas from escaping to the outside, a sliding disc 20 arranged on the shaft 8 abuts against the housing 2 . The sliding disc 20 has an inner diameter that substantially corresponds to the outer diameter of the shaft and an outer diameter that is larger than the diameter of the bearing bore 10 so that the abutment of the sliding disc 20 across the entire diameter of the bearing bore 10 is provided.
On the side of the sliding disc 20 axially opposite the housing 2 and the bearing bore 10 , a collar bush 22 is arranged on the shaft 8 . This collar bush 22 is pressed by a spring 24 against the sliding disc 20 and thus against the housing 2 . For this purpose, the spring 24 is supported on a plate 26 fastened on the shaft 8 and at the end thereof, the plate serving as a lever for adjusting the shaft 8 . Correspondingly biased, the spring 24 abuts against the plate 26 by its first end, and its second end abuts against a shoulder 28 formed on the outer diameter of the collar bush 22 .
In order to additionally prevent a leakage flow along the shaft 8 between the shaft 8 and the collar bush 22 , the inner diameter of the collar bush 22 and the outer diameter of the shaft 8 are formed with a respective groove 30 , 32 . In FIG. 1 , the groove 30 formed in the shaft 8 is closer to the bearing 12 than the groove 32 of the collar bush 22 . The collar bush 22 here serves as a sealing means cooperating with the groove 30 since it closes the groove 30 in the radial direction and thereby allows the forming of turbulences in the groove 30 . In addition, the volume of the groove 30 is smaller than that of the groove 32 . A further pressure reduction is thus achieved.
When a gas flows through the channel 4 , there is a risk that this gas escapes outward along the shaft 8 between the bearing 12 and the shaft 8 . If high pressure prevails in the channel 4 , an outward directed driving pressure gradient exists. Due to the vent bore 14 , the same pressure prevails behind the bearing 12 as in the channel so that a flow along the bearing can be reduced significantly.
In addition, however, care should be taken that no gas can escape outward through the vent bore 14 due to the pressure difference prevailing there. Gas flowing along the shaft 8 and into the gap between the collar bush 22 and the shaft 8 will first reach the groove 32 . Due to the additional space existing there, a turbulence forms in the groove, whereby a flow resistance is created. The same occurs in the groove 30 disposed therebehind. Due to the fact, however, that this groove 30 has a smaller volume, the pressure is reduced relative to the groove 32 so that the driving pressure gradient is reduced. Because of these measures, the leakage values can be reduced significantly.
The embodiment in FIG. 2 differs from that in FIG. 1 only in that the groove 32 of the collar bush 22 is closer to the bearing 12 than the groove 30 in the shaft 8 . The functioning is, however, substantially identical to that described with reference to FIG. 1 , while it is again possible to make the groove 32 smaller than the groove 30 in the shaft 8 in order to intensify the sealing effect.
In the embodiment of the present invention illustrated in FIG. 3 , a slit metal sealing ring 34 is provided in the groove 30 as a sealing means cooperating with the same, the ring being arranged in the groove 30 . Seen from the channel 4 , the groove is again arranged behind an opening of the vent bore 14 into the bearing bore 10 . Contrary to the previously described embodiments illustrated in FIGS. 1 and 2 , the groove 30 and the slit metal sealing ring 34 are situated radially inside the bearing bore 10 . The outer circumference of the sealing ring 34 is biased to abut against an inner circumferential wall 38 of the bearing bore 10 . In the context of the present application, a slit metal sealing ring is a kind of piston ring that has an axial separation plane so that its diameter is slightly variable. The separation plane can, for example, not be strictly axial, but extend obliquely, i.e., under an angle to the center axis, or extend in a step-like manner so that an axially continuous gap is avoided that could serve as a flow gap with little flow resistance. The two ends of the sealing ring 34 accordingly at least abut against each other in the axial direction.
A sealing effect in the groove 30 , i.e., at the inner circumference of the sealing ring 34 , is produced by the existing pressure difference by which the sealing ring 34 is pressed against the wall 40 axially delimiting the groove 30 . In this embodiment, the collar bush can therefore be omitted.
In FIG. 4 , another modification of the embodiment illustrated in FIG. 1 is shown. Here, the sealing ring 34 abuts against a shoulder 42 formed, seen from the channel 4 , immediately behind the opening 36 of the vent bore 14 into the bearing bore 10 . For a better sealing effect, the sealing ring 34 is pressed against the shoulder 42 by the spring 24 so that a gas flow in the radial direction is prevented by means of the abutment surface of the sealing ring 34 . The gas will accordingly not reach the outer circumference of the sealing ring 34 .
Sealing arrangements for control devices are thus provided that achieve a good sealing effect both along the shaft and across the circumference of the sealing elements. Clearly better leakage values can thus be achieved, while the control devices remain cost-effective to produce and simple to assemble.
It should be understood that the scope of protection is not limited to the embodiments described herein, but that various structural modifications are conceivable, in particular with respect to the structure of the control device, depending on the application. | A sealing arrangement for a control device of an internal combustion engine includes a housing. A channel is formed in the housing. The channel has a gas flow therethrough. A control member controls a flow of the gas in the channel. The control member is arranged on a shaft. A bearing supports the shaft in a bearing bore of the housing. A vent bore extends in the housing from an inner wall of the channel on an inlet side of the control member to a rear side, facing outward from the channel, of the bearing arranged in the housing, and into the bearing bore. A first groove is formed in the shaft behind the bearing. The first groove is configured so as to be circumferential when seen from the channel. The first groove is surrounded radially by a sealing device which is configured to cooperate with the first groove. | 5 |
[0001] The present application is a division of U.S. application Ser. No. 10/348,834, which was filed on Jan. 22, 2003, is assigned to the assignee of the present application, and is incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
[0002] This invention relates generally to a system and method for storing data. More particularly, this invention relates to protecting stored data efficiently.
[0003] Over time in a typical computer environment, large amounts of data are typically written to and retrieved from storage devices connected to the computer. As more data are exchanged with the storage devices, it becomes increasingly difficult for the data owner to reproduce these data if the storage devices fail. One way of protecting data is by backing up the data to backup media (e.g., tapes or disks). Such backup is typically performed manually or automatically at preset intervals using backup software. The backup media are then stored away in a safe location. Continuous backups result in a collection of backup media. Because of space constraints, however, backup media are generally only kept for a finite period of time, and then the oldest backup medium is written over with the newest backup data. The length of this time period, or “backup window,” thus depends on the number of backup media and the amount of data each medium contains.
[0004] Making full backups of a system is very time-consuming. One way to reduce the need for full backups, thereby increasing the backup window, is to perform incremental or differential backups between full backups. An incremental backup backs up only files that have changed since the last full or incremental backup. A differential backup backs up every file that has changed since the last full backup. The difference between the two is shown in the following example. Assume a full backup is performed weekly, e.g., every Saturday night, and the incremental or differential backup is performed nightly. In order to restore data corrupted or lost on Friday, a system using incremental backup requires the full backup from the previous Saturday, as well as each incremental backup from the intervening five nights. A system using differential backup also requires the full backup from the previous Saturday, but only requires the differential backup made on Thursday night, because that includes all the files changed since the previous Saturday. Thus, each incremental backup takes less time and stores less data than a differential backup, but a differential backup allows corrupted or lost data to be restored more easily and quickly.
[0005] One method of performing an incremental or differential backup is to set an “archive flag” for each file after it is backed up. If the file is changed (or is new), the archive flag is reset. Then, during the subsequent backup, the backup software only looks for files whose archive flags have been reset.
[0006] One disadvantage of incremental and differential backup is that the scope of the archive flag is limited to an individual computer. When backing up two or more different computers, such as those found in a network, the files on both computers must be backed up. An archive flag system backs up the files on a first computer, and any identical files loaded on the second computer will have their archive flag reset on that computer, indicating that those files should also be backed up. Such backup of identical files on the second computer is a duplication of space and effort, however, because only one backup copy of any specific file need be available. Another disadvantage of the archive flag system is that if a large file is modified only slightly, the archive flag will be reset, no matter how small the change is, and the entire file will have to be backed up again.
[0007] This latter limitation is addressed by U.S. Pat. No. 5,559,991 to Kanfi, issued Sep. 24, 1996. That patent discloses performing an incremental backup by dividing a file into blocks, generating a signature for each block, and backing up the block if the signature differs from a signature generated for an earlier version of the block. If the signature is the same, no backup is necessary. The backup computer (i.e., the computer controlling the backup) associates each block with the file from which it came. The advantage of this backup process is that if a large file is only slightly modified, only the modified blocks will be backed up, not the whole file. However, the process is limited to backing up versions of specific, named files on individual computers, even if the identical file (or data block) is located on the same computer but under a different name or it is located on another computer on the same network.
[0008] Another reference attempts to solve this last limitation. U.S. Pat. No. 6,374,266 to Shnelvar, issued Apr. 16, 2002, discloses dividing data to be backed up into data units, generating a hash value for each data unit, and backing up the data unit if the hash value does not match a hash value saved in a table. If the generated hash value does match one in the table, the method compares the actual data in the data unit to the data associated with the hash value in the table. If the data are the same, the data in the data unit are not backed up; if the data are not the same, then the data unit is backed up, and the table is updated to reflect the addition. This method is able to back up data from multiple computers and does not back up identical data units that reside on different computers.
[0009] The method of the Shnelvar patent, however, is not efficient because whenever there is a hash-value match, that method compares the actual data in the data unit to the data associated with the hash value in the table. In Shnelvar, a hash-value match can occur when the data units giving rise to the hash values are the same or when there is a hash-value “collision” —when the data units are different but the generated hash values are the same. Shnelvar performs a data comparison because of the possibility of hash-value collisions. However, in a system in which much of the data does not change between backups, there will be numerous hash-value matches, and the backup will spend a significant amount of time comparing the actual data, especially if the data are not local to the computer being backed up, or are only available over a low-speed data link.
SUMMARY OF THE INVENTION
[0010] The inefficiency of the Shnelvar patent can be avoided by using a substantially collision-free hash-optimized backup process. A hash-optimized backup process takes data blocks and generates a probabilistically unique digital fingerprint of the content of that data block. The process compares the generated fingerprint to a database of stored fingerprints and, if the generated fingerprint matches a stored fingerprint, the data block is determined to already have been backed up, and therefore does not need to be backed up again. Only if the generated fingerprint does not match a stored fingerprint is the data block backed up, at which point the generated fingerprint is added to the database of stored fingerprints. Because the algorithm is substantially collision-free, there is no need to compare actual data content if there is a hash-value match.
[0011] More particularly, a method of the present invention allows for auditing license restrictions of a computer program in an enterprise computing environment. In accordance with one embodiment, a method is disclosed, comprising generating a digital fingerprint of at least one file in the computer program using a substantially collision-free algorithm, generating a digital fingerprint for each file on each computer in the enterprise using the substantially collision-free algorithm, comparing the digital fingerprints from the enterprise files with the digital fingerprint of the computer program file, and counting the number of fingerprint matches. A similar method in accordance with another embodiment of the invention allows for inventorying a computer program in an enterprise computing environment. In both of these methods, the file may be divided into data blocks, and a digital fingerprint generated for each data block.
[0012] When used herein, a “storage device” can mean a disk drive, a memory-based storage system, an optical disk, or a logical partition within a data storage device.
[0013] Additional advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The accompanying drawings, in which like reference numerals represent like parts, are incorporated in and constitute a part of the specification. The drawings illustrate presently preferred embodiments of the invention and, together with the general description given above and the detailed description given below, serve to explain the principles of the invention.
[0015] FIG. 1 is a block diagram illustrating a system for backing up data in accordance with an embodiment of the present invention;
[0016] FIG. 2 is a block diagram illustrating storage within a storage device in accordance with an embodiment of the present invention;
[0017] FIG. 3 is a flowchart depicting backing up data in accordance with an embodiment of the present invention; and
[0018] FIG. 4 is a schematic depicting the contents of the backup databases in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] FIG. 1 illustrates an embodiment of the present invention. System 100 includes any number of computers 110 (three of which, 110 -A, 110 -B, 110 -C, are shown in FIG. 1 ) connected to backup server 150 via network 140 . As shown in FIG. 1 , computers 110 are optionally connected to each other over network 140 . Connected to backup server 150 via communication path 155 , which may be, for example, a Fibre Channel or SCSI connection, is storage device 160 . Backup server 150 is a central computer whose main function is to back up or archive data stored on other computers and servers on a computer network. Network 140 may be, for example, a LAN, a WAN, a MAN, or an internetwork of computers, such as the Internet. Storage device 160 acts as the backup (or archive) device for computers 110 and has a large capacity (e.g., terabytes). In order to satisfy the backup needs for system 100 , there may be more than one storage device 160 connected to backup server 150 . In system 100 , computers 110 typically include local storage 115 (e.g., a hard disk drive) for saving data and files between backups. Alternatively, computers 110 may have no local storage and be part of a storage area network (SAN) in which case another server (not shown) connected to network 140 , such as a file server or a data server, stores data and files on a primary storage device connected to that server.
[0020] As shown in FIG. 2 , storage device 160 includes storage for at least backed-up data blocks in database 165 (a “data” database) and digital fingerprints in database 167 (a “metadata” database). Database 167 includes digital fingerprints and information relating (e.g., cross-referencing) the digital fingerprints to the data blocks. Database 167 also includes the location (i.e., which computer 110 and the location on that computer) from which the data blocks came, so that the data can be restored if the local storage is lost or destroyed. Because data blocks appearing on more than one computer are not backed up, storage device 160 can back up much more data and files than prior art backup systems.
[0021] Backup server 150 typically includes software that can schedule and initiate periodic backups. If computers 110 include local storage 115 , an “agent” residing on each computer 110 scans all the files on that computer, dividing the files into data blocks and computing digital fingerprints for each block. (Alternatively, the agent may reside on backup server 150 and perform these tasks via network 140 . If computers 110 do not include local storage, an agent residing on the data or file server of the SAN performs these tasks.) For each block, each computer 110 contacts backup server 150 , which compares the digital fingerprint of that block to those in database 167 and determines if there is a match. If there is a match, there is no need to copy the data block to storage device 160 because the data block is already there. In such a case, database 167 will be updated to include a cross-reference from the digital fingerprint to the current data block's source or location. If there is no match, the data block is copied to storage device 160 , and the digital fingerprint and data block location are added to database 167 . The backup thus consists of backed-up data blocks database 165 , a list of the digital fingerprints, and the data block or blocks associated with each of the digital fingerprints (along with the data block's origin information).
[0022] The flowchart 300 in FIG. 3 shows how the backup process operates. First, in step 310 , each file may be divided into data blocks. The size of these blocks may be fixed or variable, depending on the operating system or the system administrator's preferences. Fixed blocks are easier to manage, but may waste space. Variable blocks make a better use of the available backup space, but are somewhat more difficult to keep track of. In addition, the size of the blocks may vary from file to file. For instance, one option may be to have each file contain a set number of blocks, N—the size of each block from a larger file of size S1 would be S1/N and the size of each block from a smaller file of size S2 would be S2/N, where S1/N>S2/N. A special case of a variable-sized block is the whole file itself (i.e., where N=1), however, it is likely more advantageous to have smaller-sized blocks in order to avoid having to save large files that change only slightly between backups. In addition, the size of the blocks may be limited by the requirements of the specific algorithm used to create the digital fingerprint.
[0023] Once the files are divided into data blocks, step 320 generates a digital fingerprint for each data block. The algorithm for generating the fingerprint is preferably a hash function. A hash function performs a transformation on an input and returns a number having a fixed length—the hash value. Properties of a hash function as used in the present invention are that it should (1) be able to take a variable-sized input and generate a fixed-size output, (2) compute the hash value relatively easily and quickly for any input value, and (3) be substantially (or “strongly”) collision-free. Hash functions satisfying these criteria include the MD5 and SHA-1 algorithms, although others are available or will be available in the future.
[0024] The MD5 (“message digest 5 ”) algorithm was created by Professor Ronald Rivest of MIT and RSA Laboratories. It generates a 16-byte (128-bit) hash value. It is designed to run on 32-bit computers. Earlier algorithms created by Professor Rivest, MD2 and MD4, developed in 1989 and 1990, respectively, also produce 128-bit hash values, but have been shown not to be substantially collision-free. MD5 was created in 1991 and is slightly slower than MD4, but more secure. MD5 is substantially collision-free. Using MD5, fingerprints may be generated at high speed on most computers.
[0025] The SHA-1 (“secure hash algorithm”) algorithm was developed in 1994 by the U.S. National Institute of Standards and Technology (NIST). It generates a 20-byte (160-bit) hash value. The maximum input length of a data block to the SHA-1 algorithm is 264 bits (˜1.8×1019 bits). The design of SHA-1 is similar to that of MD4 and MD5, but because its output is larger, it is slightly slower than MD5, but more collision-free.
[0026] Before performing the first backup for backup server 150 , data database 165 and metadata database 167 are empty. Thus, there can be no fingerprint matching as called for in step 330 . Instead, flowchart 300 proceeds directly to step 340 to back up the data block in backed-up data blocks database 165 and record in database 167 the digital fingerprint and the source of the data block (i.e., the file path, including which computer 110 and where the data block resides on the computer). Step 350 asks whether any more data blocks need to be backed up. If so, then step 360 generates the digital fingerprint for the next block in the same manner as was done in step 320 . Now, because data database 165 and metadata database 167 are not empty, step 330 compares the digital fingerprint of the data block being backed up to the stored digital fingerprint. Because the hash function generating the digital fingerprint is substantially collision-free, if there is a match, it is assumed that the data block has been backed up already and therefore step 335 only has to update database 167 to associate that digital fingerprint with the source of the data block. If there is no match, step 340 backs up the data block in backed-up data blocks database 165 and records in database 167 the digital fingerprint and the source of the data block. This loop of steps 360 , 330 , 335 / 340 , and 350 continues until there are no more data blocks on any of the computers 110 to back up. In that case, step 350 returns NO and the backup is complete in step 390 .
[0027] FIG. 4 shows one way of illustrating the contents of databases 165 and 167 during a backup of computers 110 -A to 110 -R. Database 165 includes a list of all the data blocks that have been backed up. Database 167 includes column 410 for the digital fingerprint for each data block and columns 420 - 1 , 420 - 2 , 420 - 3 , etc., for the source(s) (i.e., computer and block location) of those data blocks. Thus, the first data block, 1 , is placed in database 165 , and its digital fingerprint, FP 1 , is placed in database 167 , along with the source computer, 110 -A, and the location, “Loc”. “Loc” may be a memory or a cluster location in the source computer, and uniquely identifies the data block's source location at the time of backup. Consecutive data blocks 1 , 2 , 3 , etc. do not have to come from adjacent locations in the source computer. For example, a file may be made up of 200 data blocks that will be placed in database 165 consecutively, but their locations on the source computer do not have to be consecutive.
[0028] The next data block whose fingerprint does not match any fingerprint in column 410 is numbered data block 2 and placed in database 165 . Its fingerprint, FP 2 , is placed in column 410 along with the location in computer 110 -A. If the fingerprint of the data block does match an existing fingerprint, the data block itself is not backed up again, but the location in computer 110 -A is noted in column 420 - 2 (see, e.g., the entry for data block 4 , which is located in two places in computer 110 -A). Although only three columns 420 are shown in FIG. 4 , there can be many columns 420 , each one recording the location of the same data block at different locations on the same computer or on different computers. Thus, data block 1 also exists on computer 110 -R and data block 2 also exists on computers 110 -B and 110 -D. The process continues until all of the A (where A is an integer) unique data blocks from computer 110 -A have been backed up.
[0029] The next block to be backed up comes from computer 110 -B. If this block is unique, it is numbered data block A+1 and is placed in database 165 . Its fingerprint, FP A+1, is then placed in column 410 along with the location in computer 110 -B. If the fingerprint of the data block matches an existing fingerprint, however, the data block itself is not backed up again, but the location in computer 110 -B is noted in the next appropriate column 420 (see, e.g., the entry for data block 2 , which is located in computers 110 -A and 110 -B). Thus, data block A+1 also exists on computers 110 -C and 110 -D, data block A+2 also exists on computer 110 -D, and data block A+3 also exists on computers 110 -G and 110 -H. This process continues until all of the B-A (where B is an integer) unique data blocks from computer 110 -B have been backed up.
[0030] The next block to be backed up comes from computer 110 -C. If this block is unique, it is numbered data block B+1 and is placed in database 165 . Its fingerprint, FP B+1, is then placed in column 410 along with the location in computer 110 -C. If the fingerprint of the data block matches an existing fingerprint, however, the data block itself is not backed up again, but the location in computer 110 -C is noted in the next appropriate column 420 (see, e.g., the entry for data block A+1, which is located in computers 110 -B, 110 -C, and 110 -D). Thus, data block B+1 also exists on computers 110 -H and 110 -M. This process continues until all of the C-B (where C is an integer) unique data blocks from computer 110 -C have been backed up. The process then continues in the same manner for each of the computers from 110 -D to 110 -R.
[0031] The process of the present invention is more efficient than that of the prior art because the substantially collision-free nature of the hash function allows a hash-value match to represent a data block that is already backed up, and the actual data do not have to be compared to confirm that that is so.
[0032] In addition, because each backup generates a digital fingerprint for all the data blocks on the system being backed up, it is a full backup, unlike the traditional incremental or differential backup, and the fingerprint database 167 and backed-up data blocks database 165 exist permanently. In the event of lost or destroyed data, data restoration can be performed using only the most recent backup.
[0033] The present invention has many applications. An obvious application is within an enterprise environment, such as a networked office, in which a local area network 140 connects many computers 110 . These computers 110 are generally configured similarly, typically having the same operating system files and basic application (e.g., word processors, e-mail, spreadsheet, presentation, etc.) programs. Because of the redundancy of these files, there is no need to back up all of the files on all of the computers—doing so would take up much-needed backup space. Using the present invention, however, allows an organization to make one backup copy of these identical files and then note the locations of those files on the other computers 110 . If a single backup server 150 were used to back up all of the computers in the organization, the database would very quickly build up a list of the most common duplicated files. Once the initial backup is made in backed-up data blocks database 165 , the data blocks (and the files made up by those blocks) never have to be backed up again. When new computers 110 are deployed, it is likely that all of the initial files on those computers are already contained in the backed-up data blocks database 165 , thus making the initial backup of a new or existing computer extremely efficient, especially in a centralized computing environment.
[0034] This application can be extended to a MAN or a WAN, which network extends beyond the physical boundaries of a floor or a building. Because digital fingerprints can be efficiently delivered to backup server 150 for comparison to database 167 and because not every data block must be backed up, the present invention is especially suited for such remote operation.
[0035] The invention, however, is not limited to backing up files from computers that are related to each other, such as those within an organization. The invention can be used to back up computers (related or non-related) over the Internet. In such an application, the Internet is network 140 . Even though the computers 110 may not be from the same organization, they may contain many identical files, such as operating system files and popular software packages. Each computer 110 can have a backup agent that scans the files on that computer, dividing the files into data blocks and computing digital fingerprints for each block. For each block, computer 110 transmits over network 140 the fingerprint to backup server 150 , which compares the digital fingerprint to those in database 167 and determines if there is a match. If there is a match, database 167 updates the fingerprint to include the source, but there is no need to copy the data block to storage device 160 because the data block is already there. If there is no match, the data block is transmitted over network 140 to backup server 150 and copied to storage device 160 , and the digital fingerprint and source are added to database 167 . Prior art backup methods that compare the actual data when a match is found could not be used in such an application because there is usually not enough bandwidth between computer 110 and backup server 150 to perform such a backup efficiently. Prior art schemes therefore generally contemplate having the source computer and the backup server near each other or connected by high-bandwidth lines.
[0036] The invention can also be used in auditing. In such an application, auditors can assess the backup record of any computer within an enterprise to determine what is on that computer, without actually having to restore a tape. Auditors could easily ensure that computers in the enterprise have the proper operating system service packs installed without having to visit those machines. If the auditors wanted to know how many computers have a specific software package installed to verify the enterprise is in compliance with licensing requirements, they can determine that by comparing the fingerprints of one or more files within the various popular software packages in question with fingerprints generated from files in the computers in the enterprise. This could be performed by generating fingerprints for data blocks or files as a whole. Each match would count as having the particular software package in question.
[0037] This idea can be extended for use as an inventory tool. A system administrator could set up a database of the fingerprints of one or more files within the various popular software packages and then compare the database to the fingerprints of the files or data blocks of each computer in the system (or even of external computers, e.g., over the Internet). Again, each match would count as having the particular software package in question.
[0038] The present invention can be used to manage enterprise systems. Digital fingerprints can be used to prevent users from installing new programs without authority, or at least to monitor such installations.
[0039] The present invention can be used to detect viruses or other file tampering, including any unwanted type of “malicious software” (a.k.a. “malware”), such as adware, spyware, worms, and other software installed without permission. When loading a file having a known digital fingerprint, the file's fingerprint (or those of a file's data blocks) can be checked to see that it has not been changed since the file was last saved. If the fingerprint has changed, the file is likely to have been tampered with or infected by a virus. In addition, a digital fingerprint for a virus-infected file (or data block) may be determined, thereby allowing detection of the virus by fingerprint alone.
[0040] There are thus many benefits of the present invention. It improves backup efficiency and recovery (restoration) speed by reducing backup redundancy. Already backed-up files are readily identifiable. Blocks of data smaller than a whole file are backed up, thus reducing the need to backup whole files having minor changes. In an enterprise environment, in which many of the computers have the same files, the invention eliminates the need to save all of the files on all of the computers, only the files that are unique to each computer. Data can be backed up across a network such as the Internet with relative ease and speed.
[0041] Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the present invention in its broader aspects is not limited to the specific embodiments, details, and representative devices shown and described herein. Accordingly, various changes, substitutions, and alterations may be made to such embodiments without departing from the spirit or scope of the general inventive concept as defined by the appended claims. | A method is provided to audit license restrictions of a computer program in an enterprise computing environment. In one example, a digital fingerprint is generated of at least one file in the computer program using a substantially collision-free algorithm, and a digital fingerpring is generated for each file on each computer in the enterprise using the substantially collision-free algorithm. The digital fingerprints from the enterprise files are compared with the digital fingerprint of the computer program file, and the number of fingerprint matches is counted. Another method is provided for inventorying a computer program in an enterprise computing environment. In examples of both methods, a file may be divided into data blocks and a digital fingerprint may be generated for each data block. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to methods and apparatus for controlling the operation of “lean-burn” internal combustion engines used in motor vehicles to obtain improved engine and/or vehicle performance, such as improved vehicle fuel economy or reduced overall vehicle emissions.
2. Background Art
The exhaust gas generated by a typical internal combustion engine, as may be found in motor vehicles, includes a variety of constituent gases, including hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NO x ) and oxygen (O 2 ). The respective rates at which an engine generates these constituent gases are typically dependent upon a variety of factors, including such operating parameters as air-fuel ratio (λ), engine speed and load, engine temperature, ambient humidity, ignition timing (“spark”), and percentage exhaust gas recirculation (“EGR”). The prior art often maps values for instantaneous engine-generated or “feedgas” constituents, such as HC, CO and NO x , based, for example, on detected values for instantaneous engine speed and engine load.
To limit the amount of feedgas constituents that are exhausted through the vehicle's tailpipe to the atmosphere as “emissions,” motor vehicles typically include an exhaust purification system having an upstream and a downstream three-way catalyst. The downstream three-way catalyst is often referred to as a NO x “trap”. Both the upstream and downstream catalyst store NOx when the exhaust gases are “lean” of stoichiometry and release previously stored NO x for reduction to harmless gases when the exhaust gases are “rich” of stoichiometry.
In accordance with one prior art method, the duration of a given lean operating excursion is controlled based upon an estimate of how much NO x has accumulated in the trap since the lean excursion began. For example, in one prior art system, a controller estimates instantaneous feedgas NO x and accumulates the estimates over time to obtain a measure representing total NO x generated during the lean excursion. The controller discontinues the lean operating excursion when the total generated-NO x measure exceeds a predetermined threshold representing the trap's nominal NO x -storage capacity, usually set at a predetermined level below the saturation level of the trap. In this manner, the prior art seeks to discontinue lean operation before the trap is fully saturated with NO x , because feedgas NO x would otherwise pass through the trap and effect an increase in tailpipe NO x emissions.
A trap purge event is thereafter scheduled, during which the engine is operated with a “rich” air-fuel mixture to release the stored NO x and rejuvenate the trap. Each purge event is characterized by a “fuel penalty” consisting generally of an amount of fuel required to release both the oxygen stored in the three-way catalyst, and the oxygen and NO x stored in the trap. Significantly, the trap's NO x -storage capacity is known to decline in a generally-reversible manner over time due to sulfur poisoning or “sulfurization,” and in a generally-irreversible manner over time due, for example, to component “aging” from thermal effects and “deep-diffusion”/“permanent” sulfurization. As the trap's capacity drops, the trap is “filled” more quickly, and trap purge events are scheduled with ever-increasing frequency. This, in turn, increases the overall fuel penalty associated with lean engine operation, thereby further reducing the overall fuel economy benefit of enabling the operation of a “lean-burn” feature.
In order to restore trap capacity, a trap desulfurization event is ultimately scheduled, during which additional fuel is used to heat the trap to a relatively-elevated temperature, whereupon a slightly-rich air-fuel mixture is provided for a relatively-extended period of time to release much of the stored sulfur and rejuvenate the trap. As with each purge event, each desulfurization event typically includes the further “fuel penalty” associated with the initial release of oxygen previously stored in the three-way catalyst and the trap. Accordingly, the prior art teaches scheduling a desulfurization event only when the trap's NO x -storage capacity falls below a critical level, thereby minimizing the frequency at which such further fuel economy “penalties” are incurred.
Unfortunately, as a further impact of trap sulfurization, empirical data suggests that a trap's instantaneous NO x -storage efficiency, i.e., its instantaneous ability to incrementally store NO x , is increasingly affected by trap sulfurization as the trap begins to fill with NO x . Specifically, while a trap's instantaneous efficiency immediately after a trap purge event is believed to remain generally unaffected by trap sulfurization, the instantaneous efficiency begins to fall more quickly, and earlier in the fill event, with increasing trap sulfurization. Such reduced trap efficiency leads to increased instantaneous NO x emissions, even when the trap is not yet “filled” with NO x .
SUMMARY OF THE INVENTION
It is an object of the invention to provide a method and apparatus for controlling a lean-burn engine of a motor vehicle which seeks to balance the respective performance impacts of increased levels of trap sulfurization and more frequent trap desulfurization in order to achieve improved engine and/or vehicle performance, such as enhanced vehicle fuel efficiency and/or reduced vehicle tailpipe emissions.
Under the invention, a method and apparatus are provided for controlling the operation of an internal combustion engine in a motor vehicle, wherein the engine generates exhaust gas including an emissions constituent, and wherein exhaust gas is directed through an emissions control device before being exhausted to the atmosphere. The method according to the invention includes determining a measure representing a performance impact of operating the engine at a first operating condition other than a near-stoichiometric operating condition, wherein the measure is based on at least one engine or vehicle operating parameter; and enabling the first operating condition based on the measure. The apparatus according to the invention includes a controller including a microprocessor arranged to determine a first measure representing a first performance impact of operating the engine at a first operating condition other than a near-stoichiometric operating condition, wherein the first measure is based on at least one engine or vehicle operating parameter; and wherein the controller is further arranged to enable the first operating condition based on the first measure.
Thus, for example, in accordance with a feature of the invention, the performance impact of continued lean-burn operation may be advantageously determined, and a lean-burn feature is advantageously enabled only when such lean-burn operation is likely to result in a positive performance impact.
In a preferred method, the performance impact is a relative efficiency or benefit calculated with reference to engine operation at the near-stoichiometric operating condition.
Other objects, features and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic of an exemplary system for practicing the invention;
FIGS. 2-7 are flow charts depicting exemplary control methods used by the exemplary system;
FIGS. 8A and 8B are related plots respectively illustrating a single exemplary trap fill/purge cycle;
FIG. 9 is an enlarged view of the portion of the plot of FIG. 8B illustrated within circle 9 thereof;
FIG. 10 is a plot illustrating feedgas and tailpipe NO x rates during a trap-filling lean engine operating condition, for both dry and high-relative-humidity conditions; and
FIG. 11 is a flow chart depicting an exemplary method for determining the nominal oxygen storage capacity of the trap.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, an exemplary control system 10 for a gasoline-powered internal combustion engine 12 of a motor vehicle includes an electronic engine controller 14 having a processor (“CPU”); input/output ports; an electronic storage medium containing processor-executable instructions and calibration values, shown as read-only memory (“ROM”) in this particular example; random-access memory (“RAM”); “keep-alive” memory (“KAM”); and a data bus of any suitable configuration. The controller 14 receives signals from a variety of sensors coupled to the engine 12 and/or the vehicle as described more fully below and, in turn, controls the operation of each of a set of fuel injectors 16 , each of which is positioned to inject fuel into a respective cylinder 18 of the engine 12 in precise quantities as determined by the controller 14 . The controller 14 similarly controls the individual operation, i.e., timing, of the current directed through each of a set of spark plugs 20 in a known manner.
The controller 14 also controls an electronic throttle 22 that regulates the mass flow of air into the engine 12 . An air mass flow sensor 24 , positioned at the air intake to the engine's intake manifold 26 , provides a signal MAF representing the air mass flow resulting from positioning of the engine's throttle 22 . The air flow signal MAF from the air mass flow sensor 24 is utilized by the controller 14 to calculate an air mass value AM which is indicative of a mass of air flowing per unit time into the engine's induction system.
A first oxygen sensor 28 coupled to the engine's exhaust manifold detects the oxygen content of the exhaust gas generated by the engine 12 and transmits a representative output signal to the controller 14 . The first oxygen sensor 28 provides feedback to the controller 14 for improved control of the air-fuel ratio of the air-fuel mixture supplied to the engine 12 , particularly during operation of the engine 12 at or near the stoichiometric air-fuel ratio (λ=1.00). A plurality of other sensors, indicated generally at 30 , generate additional signals including an engine speed signal N and an engine load signal LOAD in a known manner, for use by the controller 14 . It will be understood that the engine load sensor 30 can be of any suitable configuration, including, by way of example only, an intake manifold pressure sensor, an intake air mass sensor, or a throttle position/angle sensor.
An exhaust system 32 receives the exhaust gas generated upon combustion of the air-fuel mixture in each cylinder 18 . The exhaust system 32 includes a plurality of emissions control devices, specifically, an upstream three-way catalytic converter (“three-way catalyst 34 ”) and a downstream NO x trap 36 . The three-way catalyst 34 contains a catalyst material that chemically alters the exhaust gas in a known manner. The trap 36 alternately stores and releases amounts of engine-generated NO x , based upon such factors, for example, as the intake air-fuel ratio, the trap temperature T (as determined by a suitable trap temperature sensor, not shown), the percentage exhaust gas recirculation, the barometric pressure, the relative humidity of ambient air, the instantaneous trap “fullness,” the current extent of “reversible” sulfurization, and trap aging effects (due, for example, to permanent thermal aging, or to the “deep” diffusion of sulfur into the core of the trap material which cannot subsequently be purged). A second oxygen sensor 38 , positioned immediately downstream of the three-way catalyst 34 , provides exhaust gas oxygen content information to the controller 14 in the form of an output signal SIGNAL 0 . The second oxygen sensor's output signal SIGNAL 0 is useful in optimizing the performance of the three-way catalyst 34 , and in characterizing the trap's NO x -storage ability in a manner to be described further below.
The exhaust system 32 further includes a NO x sensor 40 positioned downstream of the trap 36 . In the exemplary embodiment, the NO x sensor 40 generates two output signals, specifically, a first output signal SIGNALl that is representative of the instantaneous oxygen concentration of the exhaust gas exiting the vehicle tailpipe 42 , and a second output signal SIGNAL 2 representative of the instantaneous NO x concentration in the tailpipe exhaust gas, as taught in U.S. Pat. No. 5,953,907. It will be appreciated that any suitable sensor configuration can be used, including the use of discrete tailpipe exhaust gas sensors, to thereby generate the two desired signals SIGNAL 1 and SIGNAL 2 .
Generally, during vehicle operation, the controller 14 selects a suitable engine operating condition or operating mode characterized by combustion of a “near-stoichiometric” air-fuel mixture, i.e., one whose air-fuel ratio is either maintained substantially at, or alternates generally about, the stoichiometric air-fuel ratio; or of an air-fuel mixture that is either “lean” or “rich” of the near-stoichiometric air-fuel mixture. A selection by the controller 14 of “lean burn” engine operation, signified by the setting of a suitable lean-burn request flag LB_RUNNING_FLG to logical one, means that the controller 14 has determined that conditions are suitable for enabling the system's lean-burn feature, whereupon the engine 12 is alternatingly operated with lean and rich air-fuel mixtures for the purpose of improving overall vehicle fuel economy. The controller 14 bases the selection of a suitable engine operating condition on a variety of factors, which may include determined measures representative of instantaneous or average engine speed/engine load, or of the current state or condition of the trap (e.g., the trap's NO x -storage efficiency, the current NO x “fill” level, the current NO x fill level relative to the trap's current NO x -storage capacity, the trap's temperature T, and/or the trap's current level of sulfurization), or of other operating parameters, including but not limited to a desired torque indicator obtained from an accelerator pedal position sensor, the current vehicle tailpipe NO x emissions (determined, for example, from the second output signal SIGNAL 2 generated by the NO x sensor 40 ), the percent exhaust gas recirculation, the barometric pressure, or the relative humidity of ambient air.
Referring to FIG. 2, after the controller 14 has confirmed at step 210 that the lean-burn feature is not disabled and, at step 212 , that lean-burn operation has otherwise been requested, the controller 14 conditions enablement of the lean-burn feature, upon determining that tailpipe NO x emissions as detected by the NO x sensor 40 do not exceed permissible emissions levels. Specifically, after the controller 14 confirms that a purge event has not just commenced (at step 214 ), for example, by checking the current value of a suitable flag PRG_START_FLG stored in KAM, the controller 14 determines an accumulated measure TP_NOX_TOT representing the total tailpipe NO x emissions (in grams) since the start of the immediately-prior NO x purge or desulfurization event, based upon the second output signal SIGNAL 2 generated by the NO x sensor 40 and determined air mass value AM (at steps 216 and 218 ). Because, in the exemplary system 10 , both the current tailpipe emissions and the permissible emissions level are expressed in units of grams per vehicle-mile-traveled to thereby provide a more realistic measure of the emissions performance of the vehicle, in step 220 , the controller 14 also determines a measure DIST_EFF_CUR representing the effective cumulative distance “currently” traveled by the vehicle, that is, traveled by the vehicle since the controller 14 last initiated a NO x purge event.
While the current effective-distance-traveled measure DIST_EFF_CUR is determined in any suitable manner, in the exemplary system 10 , the controller 14 generates the current effective-distance-traveled measure DIST_EFF_CUR at step 220 by accumulating detected or determined values for instantaneous vehicle speed VS, as may itself be derived, for example, from engine speed N and selected-transmission-gear information. Further, in the exemplary system 10 , the controller 14 “clips” the detected or determined vehicle speed at a minimum velocity VS_MIN, for example, typically ranging from perhaps about 0.2 mph to about 0.3 mph (about 0.3 km/hr to about 0.5 km/hr), in order to include the corresponding “effective” distance traveled, for purposes of emissions, when the vehicle is traveling below that speed, or is at a stop. Most preferably, the minimum predetermined vehicle speed VS_MIN is characterized by a level of NOx emissions that is at least as great as the levels of NOx emissions generated by the engine 12 when idling at stoichiometry.
At step 222 , the controller 14 determines a modified emissions measure NOX_CUR as the total emissions measure TP_NOX_TOT divided by the effective-distance-traveled measure DIST_EFF_CUR. As noted above, the modified emissions measure NOX_CUR is favorably expressed in units of “grams per mile.”
Because certain characteristics of current vehicle activity impact vehicle emissions, for example, generating increased levels of exhaust gas constituents upon experiencing an increase in either the frequency and/or the magnitude of changes in engine output, the controller 14 determines a measure ACTIVITY representing a current level of vehicle activity (at step 224 of FIG. 2) and modifies a predetermined maximum emissions threshold NOX_MAX_STD (at step 226 ) based on the determined activity measure to thereby obtain a vehicle-activity-modified NO x -per-mile threshold NOX_MAX which seeks to accommodate the impact of such vehicle activity.
While the vehicle activity measure ACTIVITY is determined at step 224 in any suitable manner based upon one or more measures of engine or vehicle output, including but not limited to a determined desired power, vehicle speed VS, engine speed N, engine torque, wheel torque, or wheel power, in the exemplary system 10 , the controller 14 generates the vehicle activity measure ACTIVITY based upon a determination of instantaneous absolute engine power Pe, as follows:
Pe=TQ*N*k I ,
where TQ represents a detected or determined value for the engine's absolute torque output, N represents engine speed, and k I is a predetermined constant representing the system's moment of inertia. The controller 14 filters the determined values Pe over time, for example, using a high-pass filter G 1 (s), where s is the Laplace operator known to those skilled in the art, to produce a high-pass filtered engine power value HPe. After taking the absolute value AHPe of the high-pass-filtered engine power value HPe, the resulting absolute value AHPe is low-pass-filtered with filter G 1 (s) to obtain the desired vehicle activity measure ACTIVITY.
Similarly, while the current permissible emissions lend NOX_MAX is modified in any suitable manner to reflect current vehicle activity, in the exemplary system 10 , at step 226 , the controller 14 determines a current permissible emissions level NOX_MAX as a predetermined function f 5 of the predetermined maximum emissions threshold NOX_MAX_STD based on the determined vehicle activity measure ACTIVITY. By way of example only, in the exemplary system 10 , the current permissible emissions level NOX_MAX typically varies between a minimum of about 20 percent of the predetermined maximum emissions threshold NOX_MAX_STD for relatively-high vehicle activity levels (e.g., for many transients) to a maximum of about seventy percent of the predetermined maximum emissions threshold NOX_MAX_STD (the latter value providing a “safety factor” ensuring that actual vehicle emissions do not exceed the proscribed government standard NOX_MAX_STD).
Referring again to FIG. 2, at step 228 , the controller 14 determines whether the modified emissions measure NOX_CUR as determined in step 222 exceeds the maximum emissions level NOX_MAX as determined in step 226 . If the modified emissions measure NOX_CUR does not exceed the current maximum emissions level NOX_MAX, the controller 14 remains free to select a lean engine operating condition in accordance with the exemplary system's lean-burn feature. If the modified emissions measure NOX_CUR exceeds the current maximum emissions level NOX ' MAX, the controller 14 determines that the “fill” portion of a “complete” lean-burn fill/purge cycle has been completed, and the controller immediately initiates a purge event at step 230 by setting suitable purge event flags PRG_FLG and PRG_START_FLG to logical one.
If, at step 214 of FIG. 2, the controller 14 determines that a purge event has just been commenced, as by checking the current value for the purge-start flag PRG_START 13 FLG, the controller 14 resets the previously determined values TP_NOX_TOT and DIST_EFF_CUR for the total tailpipe NO x and the effective distance traveled and the determined modified emissions measure NOX_CUR, along with other stored values FG_NOX_TOT and FG_NOX_TOT_MOD (to be discussed below), to zero at step 232 . The purg-estart flag PRG_START_FLG is similarly reset to logic zero at that time.
Refining generally to FIGS. 3-5, in the exemplary system 10 , the controller 14 further conditions enablement of the lean-burn feature upon a determination of a positive performance impact or “benefit” of such lean-burn operation over a suitable reference operating condition, for example, a near-stoichiometric operating condition at MBT. By way of example only, the exemplary system 10 uses a fuel efficiency measure calculated for such lean-burn operation with reference to engine operation at the near-stoichiometric operating condition and, more specifically, a relative fuel efficiency or “fuel economy benefit” measure. Other suitable performance impacts for use with the exemplary system 10 include, without limitation, fuel usage, fuel savings per distance traveled by the vehicle, engine efficiency, overall vehicle tailpipe emissions, and vehicle drivability.
Indeed, the invention contemplates determination of a performance impact of operating the engine 12 and/or the vehicle's powertrain at any first operating mode relative to any second operating mode, and the difference between the first and second operating modes is not intended to be limited to the use of different air-fuel mixtures. Thus, the invention is intended to be advantageously used to determine or characterize an impact of any system or operating condition that affects generated torque, such as, for example, comparing stratified lean operation versus homogeneous lean operation, or determining an effect of exhaust gas recirculation (e.g., a fuel benefit can thus be associated with a given EGR setting), or determining the effect of various degrees of retard of a variable cam timing (“VCT”) system, or characterizing the effect of operating charge motion control valves (“CMCV,” an intake-charge swirl approach, for use with both stratified and homogeneous lean engine operation).
More specifically, the exemplary system 10 , the controller 14 determines the performance impact of lean-burn operation relative to stoichiometric engine operation at MBT by calculating a torque ratio TR defined as the ratio, for a given speed-load condition, of a determined indicated torque output at a selected air-fuel ratio to a determined indicated torque output at stoichiometric operation, as described further below. In one embodiment, the controller 14 determines the torque ratio TR based upon stored values TQ i,j,k for engine torque, mapped as a function of engine speed N, engine load LOAD, and air-fuel ratio LAMBSE.
Alternatively, the invention contemplates use of absolute torque or acceleration information generated, for example, by a suitable torque meter or accelerometer (not shown), with which to directly evaluate the impact of, or to otherwise generate a measure representative of the impact of, the first operating mode relative to the second operating mode. While the invention contemplates use of any suitable torque meter or accelerometer to generate such absolute torque or acceleration information, suitable examples include a strain-gage torque meter positioned on the powertrain's output shaft to detect brake torque, and a high-pulse-frequency Hall-effect acceleration sensor positioned on the engine's crankshaft. As a further alternative, the invention contemplates use, in determining the impact of the first operating mode relative to the second operating mode, of the above-described determined measure Pe of absolute instantaneous engine power.
Where the difference between the two operating modes includes different fuel flow rates, as when comparing a lean or rich operating mode to a reference stoichiometric operating mode, the torque or power measure for each operating mode is preferably normalized by a detected or determined fuel flow rate. Similarly, if the difference between the two operating modes includes different or varying engine speed-load points, the torque or power measure is either corrected (for example, by taking into account the changed engine speed-load conditions) or normalized (for example, by relating the absolute outputs to fuel flow rate, e.g., as represented by fuel pulse width) because such measures are related to engine speed and system moment of inertia.
It will be appreciated that the resulting torque or power measures can advantageously be used as “on-line” measures of a performance impact. However, where there is a desire to improve signal quality, i.e., to reduce noise, absolute instantaneous power or normalized absolute instantaneous power can be integrated to obtain a relative measure of work performed in each operating mode. If the two modes are characterized by a change in engine speed-load points, then the relative work measure is corrected for thermal efficiency, values for which may be conveniently stored in a ROM look-up table.
Returning to the exemplary system 10 and the flow chart appearing as FIG. 3, wherein the performance impact is a determined percentage fuel economy benefit/loss associated with engine operation at a selected lean or rich “lean-burn” operating condition relative to a reference stoichiometric operating condition at MBT, the controller 14 first determines at step 310 whether the lean-burn feature is enabled. If the lean-burn feature is enabled as, for example indicated by the lean-burn running flag LB_RUNNING_FLG being equal to logical one, the controller 14 determines a first value TQ_LB at step 312 representing an indicated torque output for the engine when operating at the selected lean or rich operating condition, based on its selected air-fuel ratio LAMBSE and the degrees DELTA_SPARK of retard from MBT of its selected ignition timing, and further normalized for fuel flow. At step 314 , the controller 14 determines a second value TQ_STOICH representing an indicated torque output for the engine 12 when operating with a stoichiometric air-fuel ratio at MBT, likewise normalized for fuel flow. At step 316 , the controller 14 calculates the lean-burn torque ratio TR_LB by dividing the first normalized torque value TQ_LB with the second normalized torque value TQ_STOICH.
At step 318 of FIG. 3, the controller 14 determines a value SAVINGS representative of the cumulative fuel savings to be achieved by operating at the selected lean operating condition relative to the reference stoichiometric operating condition, based upon the air mass value AM, the current (lean or rich) lean-burn air-fuel ratio (LAMBSE) and the determined lean-burn torque ratio TR 13 LB, wherein
SAVINGS=SAVINGS+( AM *LAMBSE*14.65*(1 −TR — LB )).
At step 320 , the controller 14 determines a value DIST_ACT_CUR representative of the actual miles traveled by the vehicle since the start of the last trap purge or desulfurization event. While the “current” actual distance value DIST_ACT_CUR is determined in any suitable manner, in the exemplary system 10 , the controller 14 determines the current actual distance value DIST_ACT_CUR by accumulating detected or determined instantaneous values VS for vehicle speed.
Because the fuel economy benefit to be obtained using the lean-burn feature is reduced by the “fuel penalty” of any associated trap purge event, in the exemplary system 10 , the controller 14 determines the “current” value FE_BENEFIT_CUR for fuel economy benefit only once per “complete” lean-fill/rich-purge cycle, as determined at steps 228 and 230 of FIG. 2 . And, because the purge event's fuel penalty is directly related to the preceding trap “fill,” the current fuel economy benefit value FE_BENEFIT_CUR is preferably determined at the moment that the purge event is deemed to have just been completed. Thus, at step 322 of FIG. 3, the controller 14 determines whether a purge event has just been completed following a complete trap fill/purge cycle and, if so, determines at step 324 a value FE_BENEFIT_CUR representing current fuel economy benefit of lean-burn operation over the last complete fill/purge cycle.
At steps 326 and 328 of FIG. 3, current values FE_BENEFIT_CUR for fuel economy benefit are averaged over the first j complete fill/purge cycles immediately following a trap decontaminating event, such as a desulfurization event, in order to obtain a value FE_BENEFIT_MAX_CUR representing the “current” maximum fuel economy benefit which is likely to be achieved with lean-burn operation, given the then-current level of “permanent” trap sulfurization and aging. By way of example only, as illustrated in FIG. 4, maximum fuel economy benefit averaging is performed by the controller 14 using a conventional low-pass filter at step 410 . In order to obtain a more robust value FE_BENEFIT_MAX for the maximum fuel economy benefit of lean-burn operation, in the exemplary system 10 , the current value FE_BENEFIT_MAX_CUR is likewise filtered over j desulfurization events at steps 412 , 414 , 416 and 418 .
Returning to FIG. 3, at step 330 , the controller 14 similarly averages the current values FE_BENFIT_CUR for fuel economy benefit over the last n trap fill/purge cycles to obtain an average value FE_BENEFIT_AVE representing the average fuel economy benefit being achieved by such lean-burn operation and, hence, likely to be achieved with further lean-burn operation. By way of example only, in the exemplary system 10 , the average fuel economy benefit value FE_BENEFIT_AVE is calculated by the controller 14 at step 330 as a rolling average to thereby provide a relatively noise-insensitive “on-line” measure of the fuel economy performance impact provided by such lean engine operation.
Because continued lean-burn operation periodically requires a desulfurization event, when a desulfurization event is identified as being in-progress at step 332 of FIG. 3, the controller 14 determines a value FE_PENALTY at step 334 representing the fuel economy penalty associated with desulfurization. While the fuel economy penalty value FE_PENALTY is determined in any suitable manner, an exemplary method for determining the fuel economy penalty value FE_PENALTY is illustrated in FIG. 5 . Specifically, in step 510 , the controller 14 updates a stored value DIST_ACT_DSX representing the actual distance that the vehicle has traveled since the termination or “end” of the immediately-preceding desulfurization event. Then, at step 512 , the controller 14 determines whether the desulfurization event running flag DSX_RUNNING_FLG is equal to logical one, thereby indicating that a desulfurization event is in process. While any suitable method is used for desulfurizing the trap 36 , in the exemplary system 10 , the desulfurization event is characterized by operation of some of the engine's cylinders with a lean air-fuel mixture and other of the engine's cylinders 18 with a rich air-fuel mixture, thereby generating exhaust gas with a slightly-rich bias. At the step 514 , the controller 14 then determines the corresponding fuel-normalized torque values TQ_DSX_LEAN and TQ_DSX_RICH, as described above in connection with FIG. 3 . At step 516 , the controller 14 further determines the corresponding fuel-normalized stoichiometric torque value TQ_STOICH and, at step 518 , the corresponding torque ratios TR_DSX_LEAN and TR_DSX_RICH.
The controller 14 then calculates a cumulative fuel economy penalty value at step 520 , as follows:
PENALTY=PENALTY+( AM/ 2*LAMBSE*14.65*(1− TR — DSX _LEAN))+( AM/ 2*LAMBSE*14.65*(1 −TR — DSX _RICH))
Then, at step 522 , the controller 14 sets a fuel economy penalty calculation flag FE_PNLTY_CALC_FLG equal to logical one to thereby ensure that the current desulfurization fuel economy penalty measure FE_PENALTY_CUR is determined immediately upon termination of the on-going desulfurization event.
If the controller 14 determines, at steps 512 and 524 of FIG. 5, that a desulfurization event has just been terminated, the controller 14 then determines the current value FE_PENALTY_CUR for the fuel economy penalty associated with the terminated desulfurization event at step 526 , calculated as the cumulative fuel economy penalty value PENALTY divided by the actual distance value DIST_ACT_DSX. In this way, the fuel economy penalty associated with a desulfurization event is spread over the actual distance that the vehicle has traveled since the immediately-prior desulfurization event.
At step 528 of FIG. 5, the controller 14 calculates a rolling average value FE_PENALTY of the last m current fuel economy penalty values FE_PENALTY_CUR to thereby provide a relatively-noise-insensitive measure of the fuel economy performance impact of such desulfurization events. By way of example only, the average negative performance impact or “penalty” of desulfurization typically ranges between about 0.3 percent to about 0.5 percent of the performance gain achieved through lean-burn operation. At step 530 , the controller 14 resets the fuel economy penalty calculation flag FE_PNLTY_CALC_FLG to zero, along with the previously determined (and summed) actual distance value DIST_ACT_DSX and the current fuel economy penalty value PENALTY, in anticipation for the next desulfurization event.
Returning to FIG. 3, the controller 14 requests a desulfurization event only if and when such an event is likely to generate a fuel economy benefit in ensuing lean-burn operation. More specifically, at step 336 , the controller 14 determines whether the difference by which the maximum potential fuel economy benefit FE_BENEFIT_MAX exceeds the current fuel economy benefit FE_BENEFIT_CUR is itself greater than the average fuel economy penalty FE_PENALTY associated with desulfurization. If so, the controller 14 requests a desulfurization event by setting a suitable flag SOX_FULL_FLG to logical one. Thus, it will be seen that the exemplary system 10 advantageously operates to schedule a desulfurization event whenever such an event would produce improved fuel economy benefit, rather than deferring any such decontamination event until contaminant levels within the trap 36 rise above a predetermined level.
In the event that the controller 14 determines at step 336 that the difference between the maximum fuel economy benefit value FE_BENEFIT_MAX and the average fuel economy value FE_BENEFIT_AVE is not greater than the fuel economy penalty FE_PENALTY associated with a decontamination event, the controller 14 proceeds to step 340 of FIG. 3, wherein the controller 14 determines whether the average fuel economy benefit value FE_BENEFIT_AVE is greater than zero. If the average fuel economy benefit value is less than zero, and with the penalty associated with any needed desulfurization event already having been determined at step 336 as being greater than the likely improvement to be derived from such desulfurization, the controller 14 disables the lean-burn feature at step 344 of FIG. 3 . The controller 14 then resets the fuel savings value SAVINGS and the current actual distance measure DIST_ACT_CUR to zero at step 342 .
Alternatively, the controller 14 schedules a desulfurization event during lean-burn operation when the trap's average efficiency η ave is deemed to have fallen below a predetermined minimum efficiency η min . While the average trap efficiency η ave is determined in any suitable manner, as seen in FIG. 6, the controller 14 periodically estimates the current efficiency η cur of the trap 36 during a lean engine operating condition which immediately follows a purge event. Specifically, at step 610 , the controller 14 estimates a value FG_NOX_CONC representing the NO x concentration in the exhaust gas entering the trap 36 , for example, using stored values for engine feedgas NO x that are mapped as a function of engine speed N and load LOAD for “dry” feedgas and, preferably, modified for average trap temperature T (as by multiplying the stored values by the temperature-based output of a modifier lookup table, not shown). Preferably, the feedgas NO x concentration value FG_NOX_CONC is further modified to reflect the NO x -reducing activity of the three-way catalyst 34 upstream of the trap 36 , and other factors influencing NO x storage, such as trap temperature T, instantaneous trap efficiency η inst , and estimated trap sulfation levels.
At step 612 , the controller 14 calculates an instantaneous trap efficiency value η inst as the feedgas NO x concentration value FG_NOX_CONC divided by the tailpipe NO x concentration value TP_NOX_CONC (previously determined at step 216 of FIG. 2 ). At step 614 , the controller 14 accumulates the product of the feedgas NO x concentration values FG_NOX_CONC times the current air mass values AM to obtain a measure FG_NOX_TOT representing the total amount of feedgas NO x reaching the trap 36 since the start of the immediately-preceding purge event. At step 616 , the controller 14 determines a modified total feedgas NO x measure FG_NOX_TOT_MOD by modifying the current value FG_NOX_TOT_as a function of trap temperature T. After determining at step 618 that a purge event has just begun following a complete fill/purge cycle, at step 620 , the controller 14 determines the current trap efficiency measure η cur as difference between the modified total feedgas NO x measure FG_NOX_TOT_MOD and the total tailpipe NO x measure TP_NOX_TOT (determined at step 218 of FIG. 2 ), divided by the modified total feedgas NO x measure FG_NOX_TOT_MOD.
At step 622 , the controller 14 filters the current trap efficiency measure measure η cur , for example, by calculating the average trap efficiency measure η ave as a rolling average of the last k values for the current trap efficiency measure η cur . At step 624 , the controller 14 determines whether the average trap efficiency measure η ave has fallen below a minimum average efficiency threshold η min . If the average trap efficiency measure η ave has indeed fallen below the minimum average efficiency threshold η min , the controller 14 sets both the desulfurization request flag SOX_FULL_FLG to logical one, at step 626 of FIG. 6 .
To the extent that the trap 36 must be purged of stored NO x to rejuvenate the trap 36 and thereby permit further lean-burn operation as circumstances warrant, the controller 14 schedules a purge event when the modified emissions measure NOX_CUR, as determined in step 222 of FIG. 2, exceeds the maximum emissions level NOX_MAX, as determined in step 226 of FIG. 2 . Upon the scheduling of such a purge event, the controller 14 determines a suitable rich air-fuel ratio as a function of current engine operating conditions, e.g., sensed values for air mass flow rate. By way of example, in the exemplary embodiment, the determined rich air-fuel ratio for purging the trap 36 of stored NO x typically ranges from about 0.65 for “low-speed” operating conditions to perhaps 0.75 or more for “high-speed” operating conditions. The controller 14 maintains the determined air-fuel ratio until a predetermined amount of CO and/or HC has “broken through” the trap 36 , as indicated by the product of the first output signal SIGNAL 1 generated by the NO x sensor 40 and the output signal AM generated by the mass air flow sensor 24 .
More specifically, as illustrated in the flow chart appearing as FIG. 7 and the plots illustrated in FIGS. 8A, 8 B and 9 , during the purge event, after determining at step 710 that a purge event has been initiated, the controller 14 determines at step 712 whether the purge event has just begun by checking the status of the purge-start flag PRG_START_FLG. If the purge event has, in fact, just begun, the controller resets certain registers (to be discussed individually below) to zero. The controller 14 then determines a first excess fuel rate value XS_FUEL_RATE_HEGO at step 716 , by which the first output signal SIGNAL 1 is “rich” of a first predetermined, slightly-rich threshold λ ref (the first threshold λ ref being exceeded shortly after a similarly-positioned HEGO sensor would have “switched”). The controller 14 then determines a first excess fuel measure XS_FUEL_ 1 as by summing the product of the first excess fuel rate value XS_FUEL_RATE_HEGO and the current output signal AM generated by the mass air flow sensor 24 (at step 718 ). The resulting first excess fuel measure XS_FUEL 1 , which represents the amount of excess fuel exiting the tailpipe 42 near the end of the purge event, is graphically illustrated as the cross-hatched area REGION I in FIG. 9 . When the controller 14 determines at step 720 that the first excess fuel measure XS_FUEL_ 1 exceeds a predetermined excess fuel threshold XS_FUEL_REF, the trap 36 is deemed to have been substantially “purged” of stored NO x , and the controller 14 discontinues the rich (purging) operating condition at step 722 by resetting the purge flag PRG_FLG to logical zero. The controller 14 further initializes a post-purge-event excess fuel determination by setting a suitable flag XS_FUEL_ 2 _CALC to logical one.
Returning to steps 710 and 724 of FIG. 7, when the controller 14 determines that the purge flag PRG_FLG is not equal to logical one and, further, that the post-purge-event excess fuel determination flag XS_FUEL_ 2 _CALC is set to logical one, the controller 14 begins to determine the amount of additional excess fuel already delivered to (and still remaining in) the exhaust system 32 upstream of the trap 36 as of the time that the purge event is discontinued. Specifically, at steps 726 and 728 , the controller 14 starts determining a second excess fuel measure XS_FUEL_ 2 by summing the product of the difference XS_FUEL_RATE_STOICH by which the first output signal SIGNAL 1 is rich of stoichiometry, and summing the product of the difference XS_FUEL_RATE_STOICH and the mass air flow rate AM. The controller 14 continues to sum the difference XS_FUEL_RATE_STOICH until the first output signal SIGNAL 1 from the NOx sensor 40 indicates a stoichiometric value, at step 730 of FIG. 7, at which point the controller 14 resets the post-purge-event excess fuel determination flag XS_FUEL_ 2 _CALC at step 732 to logical zero. The resulting second excess fuel measure value XS_FUEL_ 2 , representing the amount of excess fuel exiting the tailpipe 42 after the purge event is discontinued, is graphically illustrated as the cross-hatched area REGION II in FIG. 9 . Preferably, the second excess fuel value XS_FUEL_ 2 in the KAM as a function of engine speed and load, for subsequent use by the controller 14 in optimizing the purge event.
The exemplary system 10 also periodically determines a measure NOX_CAP representing the nominal NO x -storage capacity of the trap 36 . In accordance with a first method, graphically illustrated in FIG. 10, the controller 14 compares the instantaneous trap efficiency η inst as determined at step 612 of FIG. 6, to the predetermined reference efficiency value η ref . While any appropriate reference efficiency value η ref is used, in the exemplary system 10 , the reference efficiency value η ref is set to a value significantly greater than the minimum efficiency threshold η min . By way of example only, in the exemplary system 10 , the reference efficiency value η ref is set to a value of about 0.65.
When the controller 14 first determines that the instantaneous trap efficiency η inst has fallen below the reference efficiency value η ref , the controller 14 immediately initiates a purge event, even though the current value for the modified tailpipe emissions measure NOX_CUR, as determined in step 222 of FIG. 2, likely has not yet exceeded the maximum emissions level NOX_MAX. Significantly, as seen in FIG. 10, because the instantaneous efficiency measure η inst inherently reflects the impact of humidity on feedgas NO x generation, the exemplary system 10 automatically adjusts the capacity-determining “short-fill” times t A and t B at which respective dry and relatively-high-humidity engine operation exceed their respective “trigger” concentrations C A and C B . The controller 14 then determines the first excess (purging) fuel value XS_FUEL_ 1 using the closed-loop purge event optimizing process described above.
Because the purge event effects a release of both stored NO x and stored oxygen from the trap 36 , the controller 14 determines a current NO x -storage capacity measure NOX_CAP_CUR as the difference between the determined first excess (purging) fuel value XS_FUEL_ 1 and a filtered measure O2_CAP representing the nominal oxygen storage capacity of the trap 36 . While the oxygen storage capacity measure O2_CAP is determined by the controller 14 in any suitable manner, in the exemplary system 10 , the oxygen storage capacity measure O2_CAP is determined by the controller 14 immediately after a complete-cycle purge event, as illustrated in FIG. 11 .
Specifically, during lean-burn operation immediately following a complete-cycle purge event, the controller 14 determines at step 1110 whether the air-fuel ratio of the exhaust gas air-fuel mixture upstream of the trap 36 , as indicated by the output signal SIGNAL 0 generated by the upstream oxygen sensor 38 , is lean of stoichiometry. The controller 14 thereafter confirms, at step 1112 , that the air mass value AM, representing the current air charge being inducted into the cylinders 18 , is less than a reference value AMref, thereby indicating a relatively-low space velocity under which certain time delays or lags due, for example, to the exhaust system piping fuel system are de-emphasized. The reference air mass value AM ref is preferably selected as a relative percentage of the maximum air mass value for the engine 12 , itself typically expressed in terms of maximum air charge at STP. In the exemplary system 10 , the reference air mass value AM ref is no greater than about twenty percent of the maximum air charge at STP and, most preferably, is no greater than about fifteen percent of the maximum air charge at STP.
If the controller 14 determines that the current air mass value is no greater than the reference air mass value AM ref , at step 1114 , the controller 14 determines whether the downstream exhaust gas is still at stoichiometry, using the first output signal SIGNAL 1 generated by the No x sensor 40 . If so, the trap 36 is still storing oxygen, and the controller 14 accumulates a measure O2_CAP_CUR representing the current oxygen storage capacity of the trap 36 using either the oxygen content signal SIGNAL 0 generated by the upstream oxygen sensor 38 , as illustrated in step 1116 of FIG. 11, or, alternatively, from the injector pulse-width, which provides a measure of the fuel injected into each cylinder 18 , in combination with the current air mass value AM. At step 1118 , the controller 14 sets a suitable flag O2_CALC_FLG to logical one to indicate that an oxygen storage determination is on-going.
The current oxygen storage capacity measure O2_CAP_CUR is accumulated until the downstream oxygen content signal SIGNALl from the NO x sensor 40 goes lean of stoichiometry, thereby indicating that the trap 36 has effectively been saturated with oxygen. To the extent that either the upstream oxygen content goes to stoichiometry or rich-of-stoichiometry (as determined at step 1110 ), or the current air mass value AM rises above the reference air mass value AM ref (as determined at step 1112 ), before the downstream exhaust gas “goes lean” (as determined at step 1114 ), the accumulated measure O2_CAP_CUR and the determination flag O2_CALC_FLG are each reset to zero at step 1120 . In this manner, only uninterrupted, relatively-low-space-velocity “oxygen fills” are included in any filtered value for the trap's oxygen storage capacity.
To the extent that the controller 14 determines, at steps 1114 and 1122 , that the downstream oxygen content has “gone lean” following a suitable relatively-low-space-velocity oxygen fill, i.e., with the capacity determination flag O2_CALC_FLG equal to logical one, at step 1124 , the controller 14 determines the filtered oxygen storage measure O2_CAP using, for example, a rolling average of the last k current values O2_CAP_CUR.
Returning to FIG. 10, because the purge event is triggered as a function of the instantaneous trap efficiency measure η inst , and because the resulting current capacity measure NOX_CAP_CUR is directly related to the amount of purge fuel needed to release the stored NO x from the trap 36 (illustrated as REGIONS III and IV on FIG. 10 corresponding to dry and high-humidity conditions, respectively, less the amount of purge fuel attributed to release of stored oxygen), a relatively repeatable measure NOX_CAP_CUR is obtained which is likewise relatively immune to changes in ambient humidity. The controller 14 then calculates the nominal NO x -storage capacity measure NOX_CAP based upon the last m values for the current capacity measure NOX_CAP_CUR, for example, calculated as a rolling average value.
Alternatively, the controller 14 determines the current trap capacity measure NOX_CAP_CUR based on the difference between accumulated measures representing feedgas and tailpipe NO x at the point in time when the instantaneous trap efficiency η inst first falls below the reference efficiency threshold η ref . Specifically, at the moment the instantaneous trap efficiency η inst first falls below the reference efficiency threshold η ref , the controller 14 determines the current trap capacity measure NOX_CAP_CUR as the difference between the modified total feedgas NO x measure FG_NOX_TOT_MOD (determined at step 616 of FIG. 6) and the total tailpipe NO x measure TP_NOX_TOT (determined at step 218 of FIG. 2 ). Significantly, because the reference efficiency threshold η ref is preferably significantly greater than the minimum efficiency threshold η min , the controller 14 advantageously need not immediately disable or discontinue lean engine operation when determining the current trap capacity measure NOX_CAP_CUR using the alternative method. It will also be appreciated that the oxygen storage capacity measure O2_CAP, standing alone, is useful in characterizing the overall performance or “ability” of the NO x trap to reduce vehicle emissions.
The controller 14 advantageously evaluates the likely continued vehicle emissions performance during lean engine operation as a function of one of the trap efficiency measures η inst , η cur or η ave , and the vehicle activity measure ACTIVITY. Specifically, if the controller 14 determines that the vehicle's overall emissions performance would be substantively improved by immediately purging the trap 36 of stored NO x , the controller 14 discontinues lean operation and initiates a purge event. In this manner, the controller 14 operates to discontinue a lean engine operating condition, and initiates a purge event, before the modified emissions measure NOX_CUR exceeds the modified emissions threshold NOX_MAX. Similarly, to the extent that the controller 14 has disabled lean engine operation due, for example, to a low trap operating temperature, the controller 14 will delay the scheduling of any purge event until such time as the controller 14 has determined that lean engine operation may be beneficially resumed.
Significantly, because the controller 14 conditions lean engine operation on a positive performance impact and emissions compliance, rather than merely as a function of NO x stored in the trap 36 , the exemplary system 10 is able to advantageously secure significant fuel economy gains from such lean engine operation without compromising vehicle emissions standards.
While an exemplary system and associated methods have been illustrated and described, it should be appreciated that the invention is susceptible of modification without departing from the spirit of the invention or the scope of the subjoined claims. | A method and apparatus for controlling the operation of a “lean-burn” internal combustion engine in cooperation with an exhaust gas purification system having an emissions control device capable of alternatively storing and releasing NO x when exposed to exhaust gases that are lean and rich of stoichiometry, respectively, determines a performance impact, such as a fuel-economy benefit, of operating the engine at a selected lean or rich operating condition. The method and apparatus then enable the selected operating condition as long as such enabled operation provides further performance benefits. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO MICROFICHE APPENDIX
[0003] Not applicable.
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] This invention relates to the field of employment systems. More particularly, the invention relates to a system and method of Internet based interaction between Applicants, Employers and Third-party Recruiters.
[0006] 2. Description of the Related Art
[0007] Job search sites currently provide, via the Internet, various types of message boards and career sites (“Job Search Systems”) that list job postings and/or job Applicant resumes and that allow the exchange of information between Employers and Applicants. These types of Job Search Systems focus on the collection, storage, retrieval, and keyword searching of either job posting or job Applicant material. For example see U.S. Pat. No. 5,832,497. Such Job Search Systems envision charging fees for access to such databases as well as related fees derived from advertising, and resale of customer-related information.
[0008] The Job Search Systems have drawbacks that limit their value to both Applicants and Employers. The first drawback is information overload for Employers. Employers have limited time available to review resumes and this has led to increased mechanical screening of resumes prior to an actual review of an Applicant's credentials. Mechanical screening however, enhanced by software systems, often provides inadequate results for the Employers. Information overload also hinders the job search of qualified Applicants. For such Applicants, there are no assurances that their qualifications will be seen by Employers because of the sheer number of resumes posted on such sites. Applicants, as a result, often receive little or no responses from continuous submissions on such Job Search Systems. This problem is recognized by many career advisors and press articles that recommend Applicants rely mostly on their personal network and “friends and family” to find a job. Of the currently unemployed, a significant number are or feel disenfranchised and give up searching altogether because of no responses from Employers. On Sep. 4, 2007, the U.S. Patent Office recognized this shortcoming in current Job Search Systems by issuing U.S. Pat. No. 7,266,523, for an electronic interview auction method for auctioning an interview for a job. While well intended, attempting to auction an interview is not an effective approach to the applicant and employer challenge and does not help to lessen the problem or succeed in the market place.
[0009] The second drawback is that the current Job Search Systems do not provide more innovative methods to reduce either intentional or unintentional profiling by Employers based on race, religion, age, and increasingly unemployment status. Patents have been submitted to help monitor Employers compliance with federal affirmative action laws For example, see US Publications 2002/0052777 and 2011/0231329. However, such patents are for after-the-fact monitoring systems. The patents do not provide a controlled process specifically designed to reduce such discrimination during, and throughout, the employer's search process. At present, other job search-systems have not implemented a method to provide a controlled interaction with the consumer via the Internet that incentivizes Employers to focus only on Applicant's credentials without profiling and prescreening.
[0010] The third drawback is that Applicants, who want to promote their resumes nationally via the Internet, must give up control of their anonymity. This curtails the rights of Applicants to advertise nationally because of the potential disclosure to current Employers. Currently, Applicants who release their resumes to national Job Search Systems risk disclosure and resulting adverse actions by their current Employers. Existing Internet sites do not provide a process that allows Applicants to promote successfully their credentials nationally, while remaining anonymous until a specific Employer or Recruiter requests their resume.
[0011] The fourth drawback is that current Job Search Systems do not provide Applicants with marketing information necessary to execute a successful marketing campaign for their next career step. Job Search Systems do not currently provide Applicants with information such as: i) how saturated a particular geographic area is with similar Applicants; ii) what the quality is of Applicants who are competing against the job Applicant and iii) whether the Applicant's promotional material is successfully reaching and being read by the target employer audience. Applicant job searches, via the Internet, are one of the few business areas where technology does not provide the Applicant advertiser with adequate marketing information to execute a successful marketing campaign.
[0012] The fifth drawback is that the traditional method of reviewing cover letters and resume reviews are cumbersome and aggravate the information overload problem discussed in this section. Existing Job Search Systems attempt to address this by mechanically prescreening the Applicants' resumes based on key words and other preformatted criteria. For example see, www.monster.com for an example of such a system. This mechanical prescreening, however sophisticated, is inadequate to ensure that Employers are seeing the credentials of the best Applicants. The mechanical attempts often result in many Applicants “gaming” the system through key word additions which results in other qualified Applicants being eliminated without their credentials being reviewed. There is a definite need for a controlled process to allow Employers to review more qualified Applicant's credentials within a limited period.
[0013] The sixth drawback is that current Job Search Systems do not attempt to provide more innovative methods to Employers to address the increasing costs of hiring new Applicants. In the current economy, cash-strapped growing companies are burdened by increasing costs related to hiring such as medical benefits, administration and training costs. The utilization of third party Recruiters is another hiring related cost expended by many employers to find and screen Applicants. All these additional costs slow the growth of companies by slowing the ability to finance the hiring of new talent. In aggregate, this problem slows the growth of the employment rolls, and the health of the economy. No current Job Search Systems or patents focus on this subject or seek controlled interactive system innovations to address this problem.
SUMMARY OF THE INVENTION
[0014] In a preferred embodiment, a programmed computer software system and method is disclosed that provides a controlled interaction between Applicants, Employers and Third-party Recruiters via an Internet Website.
[0015] The system and method are implemented via a website on the Internet wherein Applicants provide a Financial Offer to Employers to view the Applicant's Credentials Document (“ACD”). The Financial Offer is a non-binding offer to pay the Employer a set financial amount, if and when the Applicant is hired. The Financial Offer creates an incentive for the Employer to review the Applicant's Credentials Document and other information that describes the Applicant's credentials. The Applicant's Credentials Document is a preformatted summary of the Applicant's career highlights. The Financial Offer encourages Employers to view the Applicant's Credential Document and request the Applicant's resume. The Employer's request for Applicant's resume is transmitted to the Applicant through the website of the invention. The Employer's identity is confidential until the resume is requested. The Applicant's identity is confidential until they respond to the Employer's request.
[0016] It should be understood that reference to the website of invention includes the underlying database that is incorporated into the website to store, retrieve and manipulate data for use by the inventive steps described herein.
[0017] The system and method of the invention provide goals, functions, tools and benefits not contained in other Job Search Systems. The invention provides financial and social benefits not currently provided in the market place.
[0018] In a preferred embodiment, the invention includes an electronic employment method via a computer database accessible on a website on the Internet for networking and finding a job, wherein the database is located on computer hardware for storing and retrieving information and wherein the method comprises the steps of:
registering by an Applicant in the database; completing by Applicant a predefined Credentials Document that summarizes Applicant's career points and storing the Credentials Document in the database; completing by Applicant a form that includes criteria that will allow others to search for and find Applicant's Credentials Document and the criteria is stored in the database; making a non-binding offer by the Applicant to pay a set financial amount to an Employer, if and when hired; allowing the Applicant to search for job postings on the database through the website and allowing the Applicant to send Applicant's Credentials Document to the job postings; allowing Applicant's Credentials Document to be searched for and found by prospective Employers; allowing the Applicant to receive requests for the Applicant's resume from prospective Employers that have accessed and viewed Applicant's Credentials Document; allowing Applicant to review and determine whether or not to release Applicant's resume to requesting Employer; and allowing Applicant to pay the set financial amount, if and when hired, to the hiring Employer over a predetermined period of time.
[0027] The electronic employment method can also include the steps of:
registering by an Employer in the database; completing job posting material by the Employer and storing the job posting material in the database; completing a form by the Employer that includes criteria that will allow others to search for and find the job posting material and storing the criteria in the database; providing the Employer with a personal account wherein Employer can find and maintain Applicants' Credentials Documents sent in response to a job posting; allowing the Employer to search and find Applicants' Credentials Documents; allowing the Employer to access and view Applicants' Credentials Documents; and allowing the Employer to request an Applicant's resume from Applicant's Credentials Document.
[0035] The Applicant may be required to pay a registration fee when registering.
[0036] In a preferred embodiment the inventive employment system is provided via the Internet on a website comprising:
a database on computer hardware for registering an Applicant; the database being accessible on a website of the Internet; a form in the database that includes fields for Applicant to complete with data to be included in an Applicant's Credentials Document and stored in the database; a financial offer field to be completed with data in the database by the Applicant; said financial offer comprises a set financial amount; the Applicant's Credentials Document in the database being searchable by Employers, Third-party Recruiters and unregistered users; the database includes provision to allow registered Employers and Third-party Recruiters to request resume from selected Applicant and a provision to allow Applicant to determine whether or not to release Applicant's resume from the database to the requesting Employer or Third-party Recruiter; and the database includes a provision to allow Applicant to pay the set financial amount to Employer or Third-party Recruiter over a predetermined period of time.
[0045] Specifically, as will be described Item by Item below, the invention includes the following objects and advantages:
Empower Applicants to overcome the information overload problem of other Job Search Systems and have their credentials viewed by Employers (Item I). Affirmatively Reduce Profiling and Discriminatory Screening (Item II). Allow National Advertising for the Applicant with Complete Anonymity (Item III). Bring New Marketing Information and Tools to the Applicant's Job Search (Item IV). Streamline the Search Process for Employers to Increase Number of Applicants that can be reviewed in an Allotted Time Period (Item V). Empower Employers with the Ability to Reduce Their First Year Hiring Costs (Item VI). Facilitate Job Creation by providing for the Orderly Transfer of the Financial Offer from the Applicant to the Employer through Escrow Procedures (Item VII).
I. A. The Financial Offer: Promoting the Applicant's Credentials Document
[0053] Applicants must register to enroll on the website of the invention and complete a pre-formatted Applicant's Credentials Document focused on three types of credentials, i.e. Experience, Expertise, and Accomplishments. They must also fill out criteria that allow Employers to search and find their Applicant's Credentials Document. The next step allows Applicants to promote their Credentials Document by inputting a Financial Offer. This Financial Offer is a non-binding offer from the Applicant to pay a set financial amount to offset an employer's first year hiring costs if and when Applicant is hired by the Employer. The amount of the Financial Offer is entirely up to the Applicant and does not contractually bind the Applicant. It is a starting point for the Applicant and future Employer to begin discussions prior to a hiring offer. The Applicant can change the amount of the Financial Offer anytime through interaction with the website of the invention.
[0054] The Financial Offer is a promotional tool for the Applicant and encourages the Employer to view the Applicant's Credentials Document. The Financial Offer can be obtained by the Employer if after reviewing the Applicant's Credentials Document, the Employer requests a resume and subsequently hires the Applicant.
I. B. The Employer Review: Contacting the Applicant
[0055] Employers and Third-part Recruiters must register to enroll on the website of the invention and are given personal Account Pages, which act as a Dashboard, i.e. a page with tools that allow them to post job openings and receive Applicant's Credentials Documents, or alternatively to just search for Applicant's Credentials Documents based on predefined criteria.
[0056] Employers and Third-party Recruiters must deal with a physical limitation to their search for the ideal Applicant. This restriction is the amount of time an employer or recruiter has to complete their talent search. On the website of the invention, Employers are encouraged to use a small allotment of their time to review an Applicant's Credentials Document. This review is the only way on the website of the invention for an Employer to request a resume and contact the Applicant. The Applicant's identity is confidential until the Applicant sends the resume to the Employer. Therefore, reviewing the Applicant's Credentials Document is the only way to contact the Applicant and potentially obtain the Financial Offer.
II. Affirmatively Reduce Profiling and Discriminatory Screening
[0057] Currently, Applicants have no market power to prevent profiling and prescreening of their application material based on age, sex, religion or employment status. The Financial Offer (described in Item IA of this Section), provides Applicants with market power to incentivize Employers to allot time to review the Applicant's credentials through the Applicant's Credentials Document. The Financial Offer is an affirmative action tool, which will level the playing field for many Applicants. Through the market power of the Financial Offer, the Applicant obtains from the Employer an actual review of the Applicant's credentials. This overcomes the first profiled prescreening stage of many employer talent searches.
[0058] The Financial Offer also becomes a factor in the employer's entire review when subsequently an employer, after reviewing qualified credentials, then requests through the website of the invention an actual resume. Entering the final review process with qualified credentials and the Financial Offer provides the Applicant a fairer review opportunity. At this stage, the employer is allocating more time to focus on a talented person capable of showing a financial interest in their future and the employer's future. The Financial Offer therefore plays a strong counter-force to profiling and discrimination, whether intentional or unintentional, throughout the Employer's talent search.
[0000] III. Allow National Advertising for the Applicant with Complete Anonymity
[0059] On the website of the invention, Applicants have the power to advertise their credentials nationally to all Employers, whether the employer is registered or not on the website of the invention. Nationally, via the Internet, Employers can see the advertised Credentials Document and can register and request, through the website of the invention, the Applicant's resume. Upon receiving the employer's request, the Applicant can research the employer via the Internet and choose whether to release their resume and identity on an individual basis. The website of the invention, therefore, provides Applicants with a viable market process to initiate and execute national advertising campaigns without risking disclosure and adverse reactions from their current Employers.
IV. Bring New Marketing Resources, Information and Tools to the Applicants' Search
[0060] Current Job Search Systems do not provide Applicants with the market power or marketing information necessary to execute a successful marketing campaign for their next career position. In response, the website of the invention brings modern marketing tools, knowledge and techniques to the Applicant's search process.
[0061] First, in other areas of business, corporations can increase their probability of success by bringing more resources to the marketing campaign. The website of the invention provides this marketing concept to the Applicant through the power of the Financial Offer, which incentivizes Employers to allot time to review to the Applicants credentials in the Applicant's Credentials Document.
[0062] Second, on the website of the invention, all Applicants can see and review the nationally advertised Applicant's Credentials Documents of other similar Applicants. This provides Applicants with real-time market knowledge of how saturated a particular geographic market with similar competition and the quality of their competition. In response, the Applicants can modify and improve their Applicant's Credentials Document and Financial Offer in order to improve their chance of successfully marketing and reaching the eyes of employer's. Alternatively, Applicants may choose to market in different geographic areas where they now have knowledge of less market saturation.
[0063] Third, the invention provides Applicants with continuous feedback on two important gauges of their marketing success; i) how many times unregistered viewers have reviewed their Applicant's Credentials Document and ii) how many registered Employers and Third-party Recruiters have reviewed their Applicant's Credentials Document. This information also provides the Applicant with important marketing information regarding the impact of their marketing campaign, and whether additional modifications to either the Applicant's Credentials Document or Financial Offer are required.
[0064] Fourth, Applicants will know on the website of the invention whether their credentials are sufficient to attract employer's interest as all Employer requests for resume go through the website of the invention directly to the Applicant. In summary, the invention brings new marketing resources, marketing tools, and information to the Applicant. The invention turns a job search into a state-of-the-art career marketing campaign.
V. Streamline the Process for Employer Reviews
[0065] On the website of the invention, Employers can either search for relevant Applicants or post job openings and have receive Applicant's material sent directly to their personal Account page. In direct search initiatives on the website of the invention, the key words and criteria used are generic and do not attempt to accomplish any sophisticated prescreening for the employer. In the case of job postings, the employer receives all responses from interested Applicants that are registered in the database on the website of the invention.
[0066] The invention therefore, is not intended to be a mechanical prescreening or matching system like many other Job Search Systems. On the website of the invention, Employers must allot time to review job Applicant material directly, which eliminates inadequate prescreening results. Next, the invention addresses information overload by Employers by formatting and processing techniques that occur in two steps.
[0067] First, the invention transforms all job Applicant materials into an aggregate Search Results screen that describes each Applicant by a short list of criteria, which may include an Account #, Career Category, Job Title, Geographic Area, Applicant's Credentials Document (“ACD”), Desired Salary Range and Financial Offer. From this Search Results screen, all Applicants on the page can be sorted by any of the criteria for the Employer's review. The Employer can them click on any Applicant's Credentials Document on the page to bring up the Applicant's Credentials Document that corresponds to the selected Applicant.
[0068] Second, the Applicant's Credentials Document is a preformatted digest of the Applicants credentials that are divided into three categories: Experience, Expertise, and Accomplishments. Each category consists of one paragraph of condensed information regarding the Applicant. This format is designed so that an Employer can review credentials within seconds and click to the next Applicant's Credentials Document sequentially. When the Employer finds an Applicant with the desired credentials, the Employer can quickly click a “Request Resume” tab and then move on the next Applicant's Credentials Document.
[0069] The processes of the Search Results Screen and the Applicant's Credentials Document are designed to replace the less desirable mechanical prescreening and matching processes of other Job Search Systems. The inventive processes control the interaction of Applicants, Employers and Third-party Recruiters in order to return the first prescreening process to the eyes of the Employer with a method that allows the Employer to review many Applicants' credentials in the time normally allotted for just one resume.
[0000] VI. Empower Employers with the Ability to Reduce First Year Hiring Costs
[0070] This invention directly addresses the supply-side problem in the employment market by empowering Employers with the ability to reduce their first year hiring costs. On the web site of the invention, registered Applicants offer potential Employers a Financial Offer. The Financial Offer is a non-binding offer from the Applicant to pay a set financial amount to offset an Employer's first year hiring costs if and when the Applicant is hired by the Employer. Registered Employers that allot time to review the Applicant's Credentials Document can obtain this valuable option if and when they hire the Applicant.
[0071] The invention transforms the traditional job search system into a controlled new process for Employers to reduce their first year hiring costs. In doing so, the invention seeks to further the common good for all, by accelerating the ability of Employers individually, and in aggregate, to add to the employment rolls, to reduce unemployment, and to further the overall growth of the economy.
[0000] VII. Facilitates Job Creation by Providing for the Orderly Transfer of the Financial Offer from the Applicant to the Employer through Escrow Procedures
[0072] The invention further facilitates the job creation goal described under Item VI of this section by providing for the orderly transfer of the Financial Offer over a period of time from the Applicant to the Employer or Third-party Recruiter through an escrow process. In a preferred embodiment, the escrow agreement is initiated by the Applicant upon employment by the Employer. This escrow process allows the Applicant to transfer the Financial Offer to the Employer or Third-party Recruiter on a pro-rated monthly basis during the first year of employment. If the employment position terminates during the first year, for any reason, the remainder funds in the escrow account are returned to the Applicant or Third-party Recruiter. This escrow process protects the financial interests of both the Employer or Third-part Recruiter and Applicant in a controlled manner that completes the purpose of the invention. The invention brings new financial, economic, and social benefits to Applicants and to Employers or Third-party Recruiters through a controlled interaction with and between the parties via an Internet website.
BRIEF DESCRIPTION OF THE DRAWINGS
[0073] FIG. 1 shows Chart I, which illustrates the steps of the process steps performed by an Applicant.
[0074] FIG. 2 is a continuation of Chart I from FIG. 1 .
[0075] FIG. 3 shows Chart II, which illustrates the steps of the process performed by an Employer.
[0076] FIG. 4 is a continuation of Chart II from FIG. 3 .
[0077] FIG. 5 shows Chart III which illustrates the steps of the process performed by unregistered users.
[0078] FIG. 6 shows Chart IV which illustrates the steps of the process performed by a Third-party Recruiter.
[0079] FIG. 7 shows is a continuation of Chart IV from FIG. 6 .
[0080] FIG. 8 shows a Search Results Spreadsheet containing Applicants' data.
[0081] FIG. 9 shows an example of an Applicant's Credentials Document showing Experience, Expertise and Accomplishments.
DETAILED DESCRIPTION OF THE INVENTION
[0082] Refer now to the Charts in the drawings as indicated in the following table:
[0000]
Chart:
FIGS.
Focus:
I
1 and 2
Applicants
II
3 and 4
Employers
III
5
Unregistered users
IV
6 and 7
Third-party Recruiters
[0083] In a first step, Employers and Third-party Recruiters are allowed to enroll and have full access to the utility of the invention via the Internet at no cost. Reference to Recruiters is used interchangeably with the term Third-party Recruiters in this document as illustrated in Chart IV in FIGS. 6 and 7 . Employers and Recruiters are required to fill out their company and key contact information and register ( 205 , 405 ). The utilities Employers and Third-party Recruiters access includes advertising job openings (job postings), inputting criteria into the website of the invention's search engines to facilitate the ability of other users to search and find the job postings, and searching for Applicant's and requesting Applicant's Credentials Documents as described below. Job postings will be publicly and nationally advertised via the Internet, but the access to interact and contact the Employers and Third-party Recruiters on the website of the invention is limited to enrolled Applicants described in the third step, as follows. The Employer's and Recruiter's identities are not disclosed in the job postings.
[0084] A second step allows Applicants to register for a fee ( 110 B) to utilize the website of the invention and requires they fill out searchable data fields ( 122 ), which includes making a Financial Offer ( 128 ). The Financial Offer is a non-binding offer from the Applicant to pay a set financial amount over a period of time to the Employer, if and when hired, by the Employer in order to offset the Employer's first year hiring costs. The Applicant also fills out a predefined format called an Applicant's Credentials Document ( 115 ), which summarizes the Applicant's career credentials into three categories: Experience, Expertise and Accomplishments ( 120 ). This is not a resume but a concentrated highlight of the Applicant's career. The Applicant's Credentials Document 500 ( FIGS. 8 and 9 ) is the Applicant's primary promotional tool. The Applicant's Credentials Document 500 is devoid of any status information on race, national origin, sex, age or current employment status. The Applicant's Credentials Document 500 will be searchable by the public but the ability to request an Applicant's resume will be restricted to registered Employers and Recruiters. The Applicant's identity is not disclosed in the Applicant's Credentials Document 500 .
[0085] A third step allows Applicants to have access to important marketing information including the ability to see all other Applicants' Credentials Documents 144 and the Financial Offers, otherwise referred to as non-binding offers. Applicants can also review how many times their own Applicant's Credentials Document 500 has been viewed by registered Employers and Recruiters, as well as the unregistered public 146 . Based on this marketing information, Applicants can always modify their own Applicant's Credentials Document and other inputted data, including the Financial Offer, to improve their own marketing position in relation to the competition 148 .
[0086] A fourth step allows an Employer, Third-party Recruiter, Applicant or unregistered user to view a Search Results Page 600 , which shows all Applicants found from a Search Applicants action, or alternatively, shows all Applicants that responded to the Employer's or Third-party Recruiter's job postings. The Search Results Page 600 (See FIG. 8 ) is designed to show each Applicant's criteria in rows including:
[0087] i. Account # 520 ;
[0088] ii. Career category 525 ;
[0089] iii. Job title 530 ,
[0090] iv. Geographic area 535 ,
[0091] v. Applicant's Credentials Document (“ACD”) 540 ,
[0092] vi. Desired salary range 545 , and
[0093] vii. Financial Offer 550 .
[0094] Employers and Recruiters (and unregistered users) can also sort Applicants on the Search Results Page 600 by criteria. For example, to arrange Applicants by highest or lowest desired salary or Financial Offer, the heading: Desired Salary Range, or Financial Offer; respectively, would be clicked.
[0095] A fifth step allows an Employer and Recruiter to access and view an Applicant's Credentials Document 500 by clicking on the corresponding Applicant's Credentials Document link 540 (identified as ACD) in the Search Results Page (See FIG. 8 ). From the Applicant's Credentials Document 500 , an Employer and Third-party Recruiter can then request the Applicant's resume 555 (See FIG. 9 ). Applicants and unregistered users can utilize only part of this step. In other words, Applicants and unregistered users can access and view an Applicant's Credentials Document 500 , but they cannot request a resume. Only a registered Employer or Third-party Recruiter can request a resume and contact the Applicant through the website of the invention. The Employer's or Third-part Recruiter's identity is finally disclosed to the Applicant when the resume request is made at this step.
[0096] A sixth step, allows the Applicant to independently research the Employer or Third-party Recruiter to decide whether or not to reply by email directly to the Employer or Third-party Recruiter. The Applicant's identity is finally disclosed to the Employer or Recruiter only if the Applicant sends the Applicant's resume to the Employer or Third-party Recruiter. All further contacts, interviews and hiring decisions, including the final negotiated amount of the Financial Offer are handled privately between the Applicant and the Employer Third-party Recruiter.
[0097] A seventh step allows Applicants to arrange an escrow agreement if and when they are hired by the Employer or the Third-party Recruiter. This escrow process allows the Applicant to transfer the Financial Offer to the Employer on a pro-rated monthly basis during the first year of employment. If the employment position terminates during the first year, for any reason, the remainder funds in the escrow account are returned to the Applicant. This escrow process protects the financial interests of both the Employer or the Third-party Recruiter and the Applicant in a controlled manner that facilitates the innovative job creation process.
[0098] Refer now to FIGS. 1-7 , in which FIGS. 1-2 show Chart I, which illustrates the sequence of steps provided in the invention for an Applicant. The inventive website includes a database 100 . Upon visiting the website the Applicant registers in the database 105 . The invention by default is configured to require Applicant to pay a registration fee 110 B, but may also be configured to not require a registration fee 110 A. For example, limited time promotions may be offered to new Applicants or Applicants in specific in career categories or other selected criteria may be allowed to register without cost.
[0099] Next Applicant completes a predefined Applicant's Credentials Document (also referred to as “ACD”) at 115 that summarizes Applicant's career points. The ACD is then stored in the database of the website at step 117 . The ACD is summarized into the areas of: Experience, Expertise and Accomplishments at step 120 . At step 122 Applicant completes a form that includes criteria that will allow others, such as Employers and Third-party Recruiters to search for and find the ACD for the Applicant. Step 124 requires that Applicant's race, gender, age, religion other protected status identifiers, and employment status are omitted from the ACD. This prevents profiling and discrimination by Employers and/or Third-party Recruiters. The criteria may include more or less items, depending upon which factors may cause potential profiling or discrimination. Applicant's criteria, from the form, are then stored in the database of the website in step 126 . Applicant makes a non-binding financial offer, referred to as the Financial Offer, in step 128 . The Financial Offer is paid to the Employer (or Third-party Recruiter) if and when Applicant is hired.
[0100] In step 130 Applicant is allowed to search for job postings through the inventive website and is allowed to send his or her ACD to job postings. Applicant's Credential Document is made available to be searched for and to be found by Employers or Third-party Recruiters in step 132 . Applicant's identity is maintained as anonymous without providing Applicant's identity to those who review Applicant's Credentials Document 134 . In step 136 Applicant is allowed to receive requests for Applicant's resume from Employers or Third-party Recruiters that have accessed it and viewed Applicant's Credentials Document. Applicant is allowed to review Employer or Third-party Recruiter and determine whether or not to release Applicant's resume to the requesting Employer in step 138 . In step 140 Applicant is allowed to transfer the set financial amount, if and when hired, to the Employer or the Third-party Recruiter over a period of time. Applicant is allowed in step 142 to transfer the set financial amount (the Financial Offer), if and when hired, to the Employer or Third-party Recruiter over a period of time via an Escrow Service whereby the set financial amount is transferred in an orderly manner. In step 144 Applicant is allowed to review other Applicant's Credentials Documents and Financial Offers. Applicant is also allowed to review in step 146 how many times his or her Applicant's Credentials Document has been viewed by registered Employers, Third-party Recruiters or by Unregistered Users. Applicant is allowed in step 148 to modify Applicant's Credentials Document and Applicant's Financial Offer at any time. Finally in step 150 , access is allowed to the website and the database of the website by unregistered users whereby the unregistered users can search and view Applicants' Credentials Documents, but the unregistered users are restricted from access to or the ability to contact Applicants.
[0101] FIGS. 3-4 show Chart II, which illustrates the sequence of steps provided in the invention for an Employer. The inventive website includes a database 200 , which is related also to the Applicant database 100 . Upon visiting the website the Employer registers in the database 205 . The invention by default is configured to not require Employer to pay a registration fee 210 A, but may also be configured to require a registration fee 210 B. In step 214 Employer completes a job posting material that is stored in the database in step 216 . The Employer in step 222 is provided with a personal account wherein Employer can find and maintain Applicant's Credentials Documents sent in response to a job posting. Employer is allowed to search and find Applicant's Credentials Documents in step 224 . In step 226 Employer is provided access to numerous Applicant's criteria in a Search Results spreadsheet format.
[0102] In step 228 , each Applicant's criteria is set forth in a row and the criteria in a row includes: Account #, Career Category, Job Title, Geographic Area, Applicant's Credentials Document, Desired Salary Range and Financial Offer. The arrangement and selection of the criteria can be changed as desired. The Employer is able in step 230 to sort the numerous Applicants' criteria contained in the spread sheet by column as desired. The Employer can access and view a desired Applicant's Credentials Document from the Search Results spread sheet by clicking on the indicia (“ACD”). After clicking on the desired ACD, the Employer can view the desired Applicant's Credentials Document in step 234 . The Employer is allowed in step 236 to request Applicant's resume from Applicant's Credentials Document. Employer is allowed to receive the Financial Offer from the Applicant, if and when hired, over an extended period of time via an Escrow Service whereby the Financial Offer is transferred in an orderly manner in step 238 .
[0103] FIG. 5 shows Chart III, which illustrates the sequence of steps provided in the invention for unregistered users. The inventive website includes a database 300 , which is related also to the Applicant database 100 and the Employer database 200 . In step 305 unregistered users are allowed to access the inventive website and database, search and view Employer's Job Postings and Applicant's Credentials Documents. However, unregistered users are restricted in step 310 access to or the ability to contact Employers, Third-party Recruiters or Applicants.
[0104] FIGS. 6-7 show Chart IV, which illustrates the sequence of steps provided in the invention for a Third-party Recruiter. The inventive website includes a database 400 , which is related also to the Applicant database 100 , the Employer database 200 and the unregistered user database 300 , each of which together form a relational database structure that is implemented on computer hardware and manipulated on the Internet. Upon visiting the website the Third-party Recruiter registers in the database 405 . The invention by default is configured to not require Third-party Recruiter to pay a registration fee 410 A, but may also be configured to require a registration fee 410 B. In step 414 the Third-party Recruiter completes a job posting material that is stored in the database in step 416 . In step 418 the Third-party Recruiter completes a form that includes criteria that will allow others to search for and find the job posting material. The job posting criteria is stored in a database in step 420 . The Third-party Recruiter in step 422 is provided with a personal account wherein the Third-party Recruiter can find and maintain Applicant's Credentials Documents sent in response to a job posting. The Third-party Recruiter is allowed to search and find Applicant's Credentials Documents in step 424 . In step 426 the Third-party Recruiter is provided access to numerous Applicant's criteria in a Search Results spreadsheet format.
[0105] In step 428 , each Applicant's criteria is set forth in a row and the criteria in a row includes: Account #, Career Category, Job Title, Geographic Area, Applicant's Credentials Document, Desired Salary Range and Financial Offer. The arrangement and selection of the criteria can be changed as desired. The Third-party Recruiter is able in step 430 to sort the numerous Applicants' criteria contained in the spread sheet by column as desired. The Third-party Recruiter can access and view a desired Applicant's Credentials Document from the Search Results spread sheet by clicking on the indicia (“ACD”) in step 432 . After clicking on the desired ACD, the Third-party Recruiter can view the desired Applicant's Credentials Document in step 434 . The Third-party Recruiter is allowed in step 436 to request Applicant's resume from Applicant's Credentials Document. The Third-party Recruiter is allowed to receive the Financial Offer from the Applicant, if and when hired, over an extended period of time via an Escrow Service whereby the Financial Offer is transferred in an orderly manner in step 438 .
[0106] FIG. 8 illustrates the Search Results spread sheet 600 and includes the Account # 520 , Career Category 525 , Job Title 530 , Geographic Area 535 , Applicant's Credentials Document (“ACD”) 540 , Desired Salary Range 545 and Financial Offer 550 . The Applicant's Credentials Document indicia “ACD” can be clicked to open up the Applicant's Credentials Document 500 corresponding to the line on the spread sheet 600 .
[0107] The Applicant's Credentials Document 500 is illustrated in more detail in FIG. 9 . In the Applicant's Credentials Document 500 , Applicant's Experience 505 , Expertise 510 and Accomplishments 515 are provided in narrative, text block form. From the Applicant's Credentials Document 500 , an Employer or Third-party Recruiter can Request Resume by clicking on the “Request Resume” link indicated at 555 . The Salary Range is shown at 565 and the Financial Offer is shown at 570 . When reviewing Applicant's Credentials Documents, the Employer, Third-party Recruiter or unregistered user can move to a different Applicant's Credentials Document by clicking on “Previous Summary” at 560 or “Next Summary” at 575 .
[0108] The invention is not limited to the embodiments described herein and variations to the system and method, or steps provided or the order of the steps may also fall within the scope of the claims that follow. | The invention is a distribution system and method between Applicants, Employers and Third-party Recruiters designed to i) empower applicants to overcome the information overload problem of other Job Search Systems and have their credentials viewed by Employers, ii) affirmatively reduce profiling and discriminatory screening by Employers, iii) allow Applicants to execute national advertising job campaigns with complete anonymity, iv) bring new marketing information and tools to the Applicant's job search, v) streamline the search process for Employers to increase the number of Applicants that can be reviewed in an allotted time period, vi) empower Employers with ability to reduce their first year hiring costs, and vii) facilitate job creation by providing for the orderly transfer of the Financial Offer from the Applicant to the Employers through escrow procedures. | 6 |
TECHNICAL FIELD
[0001] The present invention relates to the repair of pipes used to transport water, gas and other fluids, and particularly a device for stopping a leak in a pipe.
BACKGROUND ART
[0002] A leak in a water or gas pipe may be repaired by different techniques. One of these techniques consists in stopping the leak by applying an elastomer on the cracks present on the pipe by means of a sleeve. Such a sleeve is comprised of two half-shells, the interior wall of which is made of elastomer and adapted to surround the pipe at the area where the cracks are located. The half-shells are secured together and clamped to the pipe by threaded rods or other means.
[0003] Unfortunately, stopping leaks with this type of sleeve presents numerous inconveniences. The sleeve must be clamped with considerable force so that the elastomer applies a force greater than the pressure of the fluid inside the pipe, which can sometimes reach 100 bar. The two half-shells which form the sleeve are generally made of steel and thus quite heavy and expensive. Implementation is delicate and painstaking, and may take 7 to 8 hours. Furthermore, new cracks may occur under the clamping force if the operation is not performed properly. Finally, the half-shells used to form the sleeve are adapted to a specific diameter of pipe, requiring as many diameters of shells as there are pipe diameters.
SUMMARY OF THE INVENTION
[0004] This is why the object of the invention is to provide a device for stopping a leak in a pipe which can be quickly installed and does not require considerable clamping force.
[0005] Another object of the invention is to provide a device for stopping a leak in a pipe that is light-weight, inexpensive and which can be adapted to pipes of different diameters.
[0006] The invention relates therefore to a device for stopping a leak in a pipe having at least one crack, comprising an elastomer sheet applied against the crack with a force applicator and a clamping mechanism arranged around the pipe for applying a force to the force applicator. The invention is characterized in that the force applicator includes shearing elements arranged radially in relation to the pipe and applying shearing forces on the elastomer on the location of the crack, forcing the elastomer to be deformed so as to match the shape of the crack, thereby stopping the leak.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The objects, features and advantages of the invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which:
[0008] [0008]FIG. 1 represents a pipe having cracks on which the leak stopping device according to the invention is installed,
[0009] [0009]FIG. 2A represents a bottom view of the force applicator forming part of the leak stopping device according to the invention,
[0010] [0010]FIG. 2B represents a sectional view of the force applicator represented in FIG. 2A,
[0011] [0011]FIG. 3 represents a sectional view of a first force distributor which could be used in the leak stopping device according to the invention, and
[0012] [0012]FIG. 4 represents a sectional view of a second force distributor which could be used in the leak stopping device according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0013] [0013]FIG. 1 shows a cross-sectional view of a pipe 10 designed to transport a fluid such as a liquid or a gas, and presenting cracks 12 and 12 ′ in its upper section. On these cracks is placed an incompressible elastomer sheet 14 having good creep strength, such as rubber or neoprene, and having a thickness between 0.3 and 3 cm, designed to stop the leak by penetrating into the upper part of the cracks by pressure. Above the elastomer sheet 14 is a force applicator 16 of approximately the same size as the elastomer sheet 14 and designed to apply shear forces on the elastomer sheet. A force distributor 18 , placed on top of the force applicator 16 , is designed to distribute the clamping forces caused by the tightening of a clamping strap which is comprised, in this case, of two strap portions 20 and 22 . Each strap portion is stretched between two end rods. In this manner, the strap portion 20 features the two end rods 24 and 26 while the strap portion 22 features the two end rods 28 and 30 . The end rods 24 and 28 are connected by a threaded rod 32 and the end rods 26 and 30 are connected by a threaded rod 34 . When rotated, the threaded rods are progressively introduced into the bores of the end rods of the strap portions and tighten the strap formed by the two portions around the pipe 10 . As tightening continues, shear forces are applied to the elastomer sheet 14 thereby filling the cracks 12 and 12 ′.
[0014] The force applicator 16 is shown in FIGS. 2A and 2B, and represents a bottom view of the applicator and a sectional view along A-A of said applicator, respectively. In the preferred embodiment of the invention, this applicator 16 is presented in the form of a lattice consisting of a first group of parallel partitions 40 arranged horizontally on the figure and a second group of parallel partitions 42 arranged vertically on the figure, the partitions of both groups being perpendicular to one another and integral with a support or backing 44 .
[0015] In the preferred embodiment of the invention, the applicator 16 is in the shape of a rectangular sheet measuring 100 mm×50 mm with partitions 2 mm in depth and a thickness less than 1 mm. The material preferably used is rigid yet deformable plastic such as polyamide, polypropylene or polycarbonate, or made of metal having the same deformability characteristics, namely aluminum. In this manner, the deformability of the force applicator 16 allows the same applicator to be used regardless of the diameter of the pipe to be repaired.
[0016] It should be noted that, according to variants of the preferred embodiment of the invention, the applicator 16 may not be provided with a support or backing 44 and the partitions 40 and 42 could be presented differently, that is not necessarily arranged parallel and/or perpendicular to one another. Furthermore, the applicator may be in any shape whatsoever, triangular, rectangular or hexagonal.
[0017] Whatever the arrangement of the partitions 40 and 42 may be, one essential characteristic is that they be perpendicular to the surface of the pipe when the applicator 16 is placed on the elastomer 14 , as shown in FIG. 1, that is in such a manner as to apply shear forces to the elastomer.
[0018] The force distributor 18 , illustrated in FIG. 3, is a sheet of approximately the same dimensions as that of the applicator 16 although slightly thicker, between 0.5 cm and 4 cm, the thickness being relatively thin for a pipe of small diameter and thick (4 cm, for example) for a pipe of large diameter. In the embodiment shown in FIG. 3, the thickness is constant and features grooves 50 . The fact that the grooves open during the clamping operation allow the force distributor 18 to be adapted to pipes of different diameters. The distributor 18 is preferably made of a plastic material such as polyamide, polypropylene or polycarbonate. The purpose of the distributor is to correctly distribute the clamping forces onto the force applicator 16 .
[0019] According to a variant, the force distributor may have the shape shown in FIG. 4. In this variant, it has a variable thickness which becomes thinner from the center toward the ends, for example from 2 cm to 1 cm.
[0020] Although it is not indispensable, the force distributor 18 greatly improves the efficiency of the leak stopping device according to the invention, mainly when it takes the form as shown in FIG. 4. The distributor converts the orthoradial forces into radial compression forces, the curvature of the distributor adding together with that of the pipe. In this case, the tension is no longer tangent to the surface of the system as can be seen in FIG. 1. The larger curvature allows the radial component of the tension force to be transmitted. The distributor thus allows these forces to be recovered along the entire length of the force applicator and not only at the ends. Moreover, in this manner, a force gradient increasing from the center to the ends is obtained, thereby concentrating a maximum amount of force on the leak.
[0021] In this manner, for the same clamping force enabling a pressure of 20 bar to be applied, if only the force applicator 16 is used without the force distributor 18 , this pressure exceeds 35 bar when a distributor of constant thickness according to FIG. 3 is used, and to more than 50 bar when a distributor of variable thickness as shown in FIG. 4 is used. Furthermore, whether the force distributor is of constant or variable thickness, it was noted that an increase in thickness, particularly in the center in the case of variable thickness and thus a greater distance from the clamping belt in relation to the pipe, allows a greater clamping pressure to be obtained capable of reaching 100 bar.
[0022] Generally speaking, the principle of the invention consists in applying a relatively weak clamping force owing to a characteristic mode of compression of an incompressible elastomer and having good creep strength. To this end, the elastomer is stressed according to its most flexible mode, that is shearing, by means of the force applicator and its partitions perpendicular to the surface of the pipe.
[0023] Although the above description presents a preferred embodiment of the invention, it is clear that changes can be made without departing from the framework of the invention. As such, any clamping mechanism may be used to implement the invention, such as a flexible steel cable of small diameter, for example. However, the use of straps (illustrated in FIG. 1) and in a general manner, several portions of straps which are inter-connected by appropriate clamping means that bring the strap portions ends closer to each other during the clamping operation (in particular, these clamping means may be threaded rods as described in the preferred embodiment of the invention), is a system which can be adapted to all pipe diameters, each pipe requiring possibly the use of 1, 2, 3 . . . portions of identical straps connected together. Moreover, is judicious to ensure that the portions which comprise the strap be placed in a sleeve so that part of the clamping force will not be absorbed by friction forces as it is the case when the strap rubs directly on the pipe during the clamping operation.
APPENDIX
Version with Markings to Show Changes Made
[0024] IN THE SPECIFICATION
[0025] The paragraph on page 1 between the title and the first heading is new. | A device for stopping a leak in a pipe having at least one crack, including an elastomer sheet applied against the crack with a force applicator and a clamping mechanism arranged around the pipe for applying a force on the force applicator. The force applicator includes shearing elements preferably consisting of a first group of rigid parallel partitions and a second group of parallel partitions arranged perpendicularly to the partitions of the first group, the partitions being arranged perpendicularly to the pipe and applying shearing efforts on the elastomer sheet on the site of the crack, forcing the elastomer to be deformed so as to match the shape of the crack, thereby stopping it. | 5 |
This is a continuation of application Ser. No. 08/088,031 filed Jul. 6, 1993 now U.S. Pat. No. 5,442,398.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for converting a video signal such as a television signal into a digital high-efficiency coded signal and transmitting it, a video signal transmission apparatus for use in the method, and a video signal reception apparatus.
2. Description of the Related Art
In recent years, a system for transmitting and receiving a high-resolution television signal (hereinafter referred to as a high-resolution TV signal) has been developed as a new method for transmitting and receiving a TV signal. The high-resolution TV signal has a larger number of scanning lines than that of scanning lines of a TV signal of the currently-used NTSC system (hereinafter referred to as a low-resolution TV signal), and allows an image to be formed more clearly.
To watch high-resolution television, a high-resolution television set for receiving and demodulating a high-resolution TV signal is needed. Since, however, most of viewers have NTSC television sets, if they replace the NTSC television sets with high-resolution television sets, the NTSC television sets will be useless, as will be program sources of the NTSC system. Therefore, producers of TV programs wish to transmit the low-resolution TV signals as well as the high-resolution TV signals. If, however, a transmission path for the high-resolution TV signal and a transmission path for the low-resolution TV signal are formed separately from each other, it is difficult to assign transmission bands to these transmission paths.
In order to popularize the methods for transmitting and receiving a high-resolution TV signal, television sets, such as HDTV (high definition television) sets and NTSC television sets, that the viewers possess at present, need to be used effectively. Further, it is necessary to devise the methods so as not to make program video sources of the NTSC system useless.
SUMMARY OF THE INVENTION
It is accordingly an object of the present invention to provide a method for transmitting a video signal, a video signal transmission apparatus for use in the method, and a video signal reception apparatus, in which a plurality of low-resolution TV signals can be transmitted with efficiency through a transmission path for a digital high-efficiency coded signal of a high-resolution TV signal, thereby effectively utilizing the transmission path and high-resolution TV sets without making program sources and currently-used low-resolution TV sets useless.
According to a first aspect of the present invention, there is provided a method for transmitting a video signal, comprising:
a step of synthesizing a plurality of low-resolution TV signals input from corresponding input terminals by synthesizing means, and outputting a multichannel low-resolution TV signal whose format is equal to that of a high-resolution TV signal;
a step of converting the multichannel low-resolution TV signal into a digital high-efficiency coded signal by coding means, the multichannel low-resolution TV signal being processed in the same manner as the high-resolution TV signal is; and
a step of transmitting the digital high-efficiency coded signal through A transmission path.
According to a second aspect of the present invention, there is provided a video signal transmission apparatus comprising:
input terminals from which a plurality of low-resolution TV signals are input;
synthesizing means for synthesizing the plurality of low-resolution TV signals and outputting a multichannel low-resolution TV signal whose format is equal to that of a high-resolution TV signal;
encoding means for converting the multichannel low-resolution TV signal into a digital high-efficiency coded signal; and
transmitting means for transmitting a signal output from the encoding means.
According to a third aspect of the present invention, there is provided a video transmission apparatus comprising:
a first input terminal from which a low-resolution TV signal is input;
a second input terminal from which a high-resolution TV signal is input;
converting means for converting the low-resolution TV signal into a signal having a format which is equal to that of the high-resolution TV signal;
selecting means for fitting the signal output from the converting means into the high-resolution TV signal;
encoding means for converting a signal output from the selecting means into a digital high-efficiency coded signal; and
transmitting means for transmitting a signal output from the encoding means.
According to a fourth aspect of the present invention, there is provided a video reception apparatus comprising:
an input terminal supplied with a multichannel low-resolution TV signal generated by synthesizing a plurality of low-resolution TV signals;
decoding means for decoding the multichannel low-resolution TV signal;
display processing means for converting a signal output from the decoding means, which corresponds to one of the plurality of low-resolution TV signals, into a display signal; and
display means for displaying a signal output from the display processing means.
In the above method and apparatuses, the transmission path and high-resolution TV sets can be utilized effectively, without making currently-used low-resolution TV program sources useless.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a system for transmitting and receiving a video signal according to one embodiment of the present invention;
FIG. 2 is a view for explaining an example of pictures synthesized by a picture synthesizing circuit of the system shown in FIG. 1;
FIGS. 3A, 3B and 3C are view for explaining an example of a multichannel low-resolution TV signal displayed on a monitor;
FIG. 4 is a block diagram showing an arrangement of the picture synthesizing circuit of the system shown in FIG. 1;
FIGS. 5A, 5B and 5C are timing charts for explaining an operation of the picture synthesizing circuit of the system shown in FIG. 1;
FIG. 6 is a block diagram showing an arrangement of a display processing circuit of the system shown in FIG. 1; and
FIG. 7 is a block diagram of a system for transmitting and receiving a video signal according to another embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention will now be described, with reference to the accompanying drawings.
FIG. 1 schematically shows a system for transmitting and receiving a video signal according to one embodiment of the present invention. FIG. 2 shows channels ch1 to ch4 of low-resolution TV signals in order to explain an operation of the system shown in FIG. 1.
In FIG. 1, the low-resolution TV signals of the channels ch1 to ch4 are supplied to their respective terminals 101 to 104. The terminals 101 to 104 are connected to a picture synthesizing circuit 110. Pictures P1 to P4 of the low-resolution TV signals of the channels ch1 to ch4 are synthesized by the picture synthesizing circuit 110 in such a manner that they are fit into a single picture PM as shown in FIG. 2 to generate a multichannel low-resolution TV signal (which is a four-picture signal in FIG. 2). The multichannel low-resolution TV signal is then supplied from the picture synthesizing circuit 110 to one input terminal of a selection circuit 118. The other input terminal of the selection circuit 118 is supplied with a high-resolution TV signal from a terminal 107. The selection circuit 118, which is controlled by a control signal supplied from a control terminal 108, selects a signal from the picture synthesizing circuit 110 or the terminal 107 and supplies the selected signal to a high efficiency encoding circuit 111 included in an HDTV (high definition television) encoder 120. The HDTV encoder 120 also includes a buffer circuit 112 for receiving a signal output from the high efficiency encoding circuit 111.
The high efficiency encoding circuit 111 converts a signal output from the selection circuit 118 into a high-efficiency-encoded signal and supplies it to the buffer circuit 112. The buffer circuit 112 is intended to smooth the encoded signal so as to have a fixed transmission rate and send it to a transmission path 113. When the amount of information of the encoded signal becomes large, the buffer circuit 112 controls the high-efficiency-encoding circuit 111 to reduce the amount.
The signal transmitted through the transmission path 113 is supplied to a buffer circuit 114 arranged in an HDTV decoder 121 and stored therein. A signal having a fixed transmission rate is supplied from the buffer circuit 114 to a decoding circuit 115 and decoded therein. The decoded signal is supplied to a display processing circuit 116.
When the display processing circuit 116 detects that the signal decoded by the decoding circuit 115 is a high-resolution TV signal, it supplies the decoded signal to an HDTV monitor 117 as it is. When the display processing circuit 116 detects that the decoded signal is a multichannel low-resolution TV signal, it processes an image in response to a control signal supplied to a terminal 106 from a user.
FIGS. 3A and 3B show examples of display pictures formed in accordance with a processing mode of the display processing circuit 116. FIG. 3A shows a display of four pictures synthesized by the picture synthesizing circuit 110, FIG. 3B shows a display of an enlarged one of the four pictures synthesized on the transmission side, and FIG. 3C shows a display of a main picture (master picture) obtained by enlarging one of the four pictures synthesized on the transmission side and a sub-picture (slave picture) corresponding to another one of the four pictures.
An operation of the picture synthesizing circuit 110 will be described, with reference to FIGS. 4 and 5A to 5C.
In FIG. 4, low-resolution TV signals of channels ch1 and ch4 are supplied to the terminals 101 to 104. The signal from the terminal 101 is supplied to memories 610 and 611, the signal from the terminal 102 is supplied to memories 612 and 613, the signal from the terminal 103 is supplied to memories 614 and 615, and the signal from the terminal 104 is supplied to memories 616 and 617. The memories 610 and 611 are controlled alternately by a control circuit (not shown) that one of them is set in a write mode and the other is set in a read mode. Similarly, the memories 612 and 613 are controlled alternately by the control circuit, as are the memories 614 and 615 and the memories 616 and 617. An input signal is written to the memories in the write mode, and a stored signal is read out from the memories in the read mode. The outputs of the memories 610 and 611 are supplied to a switch 620, the outputs of the memories 612 and 613 are supplied to a switch 621, the outputs of the memories 614 and 615 are supplied to a switch 622, and the outputs of the memories 616 and 617 are supplied to a switch 623. These switches 620 to 623 are controlled by a control circuit (not shown) so that a signal is selectively read out from the memories in the read mode. The read speed is faster than the write speed, and a picture corresponding to the read-out signal is reduced to, for example, 1/4 of a picture corresponding to the input signal. The output signals from the switches 620 to 623 are transmitted to a selecting circuit 630.
In the picture synthesizing circuit 110, the data writing frequency of each of the memories is, for example, 13.5 MHz, and the data reading frequency thereof is, for example, 54.0 MHz.
FIG. 5 are timing charts for explaining an operation of the selecting circuit 630. The selecting circuit 630 is supplied with control signals C1 and C2 from a control circuit (not shown) through terminals 606 and 607. The terminals 606 and 607 are supplied with control signals C1 and C2 shown in FIGS. 5A and 5B, respectively. In FIG. 5B, T4 and T5 each represent a one-line period of a low-resolution TV signal, and T6 represents a period of the sum of periods T4 and T5 which is a one-line period of the multichannel low-resolution TV signal shown in FIG. 2 (a picture PM). In FIG. 5A, T1 and T2 each represent a 1/2 vertical period of the multichannel low-resolution TV signal shown in FIG. 2 (a picture PM), and T3 represents one vertical period (one-frame period) of the multichannel resolution-low TV signal shown in FIG. 2. The selecting circuit 630 selectively outputs the signals from the switches 620 and 621 during the period T1, and outputs the signal from the switch 620 during the period T4 and the signal from the switch 621 during the period T5. Further, the selecting circuit 630 selectively outputs the signals from the switches 622 and 623 during the period T2, and outputs the signal from the switch 622 during the period T4 and the signal from the switch 623 during the period T5. As a result, channel signals are output from an output terminal 605 of the selecting circuit 630 in the sequence shown in FIG. 5C. More specifically, signals of channels ch1 and ch2 are output alternately for each line during the period T1 in which the control signal C1 is at a low level, and signals of channels ch3 and ch4 are output alternately for each line during the period T2 in which the control signal C1 is at a high level, with the result that a picture of the multichannel low-resolution TV signal includes pictures of the channels ch1 and ch2 arranged on the upper side and those of the Channels ch3 and ch4 arranged on the lower side. More specifically, in the picture synthesizing circuit 110, the same lines of a plurality of low-resolution TV signals are sampled in sequence to generate a signal corresponding to one line of a high-resolution TV signal, with the result that the low-resolution TV signals are synthesized into a multichannel low-resolution TV signal.
The multichannel low-resolution TV signal is the same as the high-resolution TV signal in line frequency, vertical frequency, and the like. Therefore, like the high-resolution TV signal, the multichannel low-resolution TV signal can be encoded and decoded.
The multichannel low-resolution TV signal output from the terminal 605 is high-efficiently encoded by the high-efficient encoding circuit 111. If, when the picture signals of the four channels are high-efficiently encoded, the amount of information of a picture signal of one of the channels is increased and the amount of information of picture signals of the other channels is decreased, the total amount of information is not decreased, and the encoded signals can be transmitted without degrading the image quality of the picture signal of the channel having a large amount of information.
In a low-resolution TV signal transmission mode, the signal output from the picture synthesizing circuit 110 is input to the HDTV encoder 120 through the selecting circuit 118. In a high-resolution TV signal transmission mode, the high-resolution TV signal supplied from the input terminal 107 is selected by the selecting circuit 118 and then supplied to the HDTV encoder 120. During the selection of the high-resolution TV signal, the selecting circuit 118 is able to select one of the low-resolution TV signals to produce a video signal representing a picture of the selected low-resolution TV signal which is fit into a picture of the high-resolution TV signal and, in this case, a control signal is supplied from a timing control circuit (not shown) to the control terminal 108 of the selecting circuit 118. Assuming that a picture of the low-resolution TV signal of channel ch1 is fit into a picture of the high-resolution TV signal, the memories 610 and 611 and switches 620 and 630 in the picture synthesizing circuit 110 operate as converting means for converting the low-resolution TV signal so that it can be fit into part of the picture of the high-resolution TV signal. This operation is substantially the same as the above-described picture synthesizing operation. Therefore, one low-resolution TV signal output from the switch 620 is selected by the selecting circuit 630 and then supplied to the selecting circuit 118.
FIG. 6 specifically shows the display processing circuit 116. Assume that a plurality of low-resolution TV signals are decoded by the decoding circuit 115 of the HDTV decoder 121. The signals output from the decoding circuit 115 in FIG. 1 are supplied to an input terminal 801 and then a switch 810. When the low-resolution TV signals are supplied, the switch 810 directly guides the signals from the input terminal 801 to a switch 821 in response to a control signal (mode selection signal) from the terminal 106, or supplies it to a memory 811 or a memory 813. When the display mode shown in FIG. 3A is selected in response to the control signal from the terminal 106, the signal of the input terminal 801 is supplied to the switch 821 as it is, and the switch 821 guides the input signal to an output terminal 802.
When the display mode shown in FIG. 3B is selected, the switch 810 supplies one of four picture signals of the input terminal 801 to the memory 811 in response to the control signal inputted from the input terminal 106. The memory 811 receives the picture signal under control of a write control circuit (not shown). The output signal of the memory 811 is supplied to an interpolation circuit 812. The interpolation circuit 812 interpolates the scanning lines of the signal supplied from the memory 811 in order to convert it into a signal to be displayed on a high-resolution display. The output of the interpolation circuit 812 is supplied to the output terminal 802 through the switches 820 and 821.
when the display mode shown in FIG. 3C is selected, one of four picture signals of the input terminal 801, which is designated as a master picture, is written to the memory 811, and another one of the picture signals, which is designated as a slave picture, is written to the memory 813. The output signal of the memory 811 is input to the interpolation circuit 812. The data writing frequency of each of the memories 811 and 813 is 54 MHz, and the data reading frequency thereof is also 54 MHz. The interpolation circuit 812 interpolates the scanning lines of the signal in order to convert it into a master picture signal. The output signal of the memory 813 is supplied to a reduction/expansion circuit 814 and reduced/expanded in the time basis direction in order to convert it into a slave picture signal. The switch 820 selects the output signal of the reduction/expansion circuit 814 during a period corresponding to the slave picture, and selects the output signal of the interpolation circuit 812 during a period corresponding to the master picture. The output signal of the switch 820 is transmitted to the output terminal 802 through the switch 821. The write clocks of the memories 811 and 813 are synchronized with each other by a timing control circuit (not shown), as are the read clocks thereof, and the read start timing is controlled in order to determine display positions of the master and slave pictures. Furthermore, the switch 820 is controlled by the timing control circuit.
When the high-resolution TV signal is decoded, the signal of the input terminal 801 is supplied to the output terminal 802 through the switches 810 and 821.
In the system of the above embodiment, a plurality of low-resolution TV signals can be synthesized and the synthesized signal can be transmitted as a multichannel low-resolution TV signal from the transmission side, and the multichannel low-resolution TV signal can be processed and displayed in an arbitrary mode on the reception side. This system can be applied to a system for transmitting and receiving a high-resolution TV signal. More specifically, since a plurality of low-resolution TV signals can be transmitted efficiently through a transmission path for a digital high-efficiency coded signal into which the high-resolution TV signal is converted, the transmission path and high-resolution television sets can be used effectively, and program sources of the NTSC system recorded on magnetic tapes or the like can be prevented from being made useless.
FIG. 7 is a block diagram showing a system for transmitting and receiving video signal according to another embodiment of the present invention. This embodiment is intended to offer a convenience to a user having a low-resolution TV signal monitor 213. In FIG. 7, the descriptions of the elements denoted by the same numerals as those in FIG. 1 are omitted. When the low-resolution TV signals of channels ch1 to ch4 are supplied to terminals 101 to 104, respectively, a high-efficiently encoded multichannel low-resolution TV signal is supplied to a selecting circuit 210 through a transmission path 113 at a fixed transmission rate. The selecting circuit 210 selects one picture signal from the multichannel low-resolution TV signal in response to a user's control signal from a control terminal 206. The output signal of the selecting circuit 210 is supplied to a buffer circuit 211. The buffer circuit 211 stores a signal supplied from the selecting circuit 210 and then supply it to a decoding circuit 212. A picture signal is supplied from the decoding circuit 212 to the low-resolution TV monitor 213. | A video transmission apparatus that has a first input terminal for receiving a low-resolution TV signal. The apparatus also has a second input terminal for receiving a high-resolution TV signal and for outputting said high-resolution TV signal. The apparatus converts the low-resolution TV signal into a signal having a format which is equal to that of the high-resolution TV signal. The apparatus selects either the signal, which has been produced by converting low-resolution TV signal into a signal having a format which is equal to that of the high-resolution TV signal, or the high-resolution TV signal, which is outputted from the second input terminal The signal, which has been produced by converting low-resolution TV signal into a signal having a format which is equal to that of the high-resolution TV signal, is fitted into the high-resolution TV signal. The apparatus encodes the selected signal into a digital high-efficiency coded signal, and outputs a signal indicative thereof. Finally, the apparatus transmits the signal produced by encoding the selected signal. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of application Ser. No. 08/202,785, filed Feb. 28, 1994, now abandoned. The disclosure of this application is expressly incorporated by reference.
BACKGROUND OF THE INVENTION
This invention relates to a fireplace, and, in particular, to a cooling passageway disposed within an air-cooled housing enclosing the combustion chamber of the fireplace.
Known in the art are a multitude of different types of combustion apparatus, including fireplaces such as freestanding models and zero clearance models. These models of fireplaces, and most particularly zero clearance fireplaces, commonly include housings or shells formed of conductive material such as sheet metal that surround the combustion chambers or fireboxes whereat combustion of fuel occurs and include a transparent glass door assembly. The walls of the housing are typically constructed in spaced relationship with some or all of the walls of the combustion chamber, including the bottom wall and top wall which form the floor and ceiling of the combustion chamber. The resulting space or plenums provided between the combustion chamber and housing permits the formation of passageways suitable to circulate air. Existing fireplaces have used these passageways to circulate air to serve a number of nonexclusive purposes, including the cooling of the exterior of the housing. Keeping the outer housing cool is of significant importance in zero clearance fireplaces where the materials externally adjacent the housing may be combustible.
One problem with some existing fireplaces is that under certain operating condition not enough air to cool the housing to a desirable level flows through the cooling passageways. In a known fireplace construction which uses an induced draft within a cooling passageway, rather than a forced draft created by a fan, air from an upper plenum of the cooling passageway which is disposed above the fireplace combustion chamber discharges directly into the forward region of the combustion chamber. This outlet air then passes rearwardly through the combustion chamber to mix with the combustion products and then pass into the flue. While in such a construction cooling air is drawn through the cooling passageway when the combustion chamber access doors are closed, conditions within the combustion chamber are such that induced air flow through the upper plenum is severely curtailed or halted when the access doors are open. Consequently, when the fireplace doors are open during operation, the stagnated air within the cooling passageway increases in temperature over time due to the heat radiating from the combustion chamber, and an undesirable increase in the temperature of the outer housing ultimately results.
Another problem with some existing fireplaces pertains to their inability to maintain at relatively low temperatures the upper forward portion of the outer housing. This problem often persists despite the fact that a cooling air plenum above the combustion chamber is provided. In particular, the air within the cooling passageway upper plenum is frequently discharged or routed downwardly in the direction of the combustion chamber. Because hotter air rises, the air within the upper plenum more inclined to be drawn through the upper plenum is the air closer to the outlet, that is, the cooler air flowing near to the combustion chamber. The hotter air which migrates upwardly tends to stagnate in the upper forward portion of the outer housing, raising the temperature thereof, when the induced draft through the plenum is not strong enough to pull the entire volume of air through the upper plenum.
What is needed in the art is a fireplace having an air-cooled outer housing which promotes adequate cooling of the forward portion of the top wall of the outer housing.
An additional need is a fireplace having an air-cooled outer housing which is adequately cooled by an induced draft of cooling air when the access doors to the combustion chamber are either open or closed.
SUMMARY OF THE INVENTION
The present invention provides a fireplace with an outer housing that encloses a cooling air passageway structured to cool the forward portion of the outer housing top wall during operation. The inventive cooling system advantageously effects an induced draft of room air through the cooling air plenum disposed above the combustion chamber even when the fireplace access doors to the combustion chamber are open. In one form thereof, the fireplace of the present invention includes a combustion chamber in which the fuel is combusted and the products of combustion are created, the combustion chamber including an opening through which combustion air is introduced and further comprising a top wall, a bottom wall, a rear wall and opposing side walls. A flue is positioned for exhausting the products of combustion from the combustion chamber. The housing comprises a plurality of outer walls, at least one of the plurality of housing outer walls disposed in spaced apart relationship with a corresponding combustion chamber wall to form at least one plenum. A cooling air inlet is in flow communication with the plenum, and the plenum comprises an upper plenum disposed between the outer top wall and the combustion chamber top wall. There is provided a passageway constricting baffle disposed within a forward portion of the upper plenum, the baffle being sized and arranged to constrict a cross-sectional area of the upper plenum through which cooling air flows and force the flow of cooling air passing through the upper plenum upwardly toward the housing outer top wall.
An advantage of the cooling system of the present invention is its ability to cool the outer housing with an induced draft of room air when the combustion chamber access doors are open.
Another advantage of the cooling system of the present invention is that the cooling air is directed over the forward inner portion of the top wall of the outer housing to ensure adequate cooling thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a fragmentary perspective view of an embodiment of the present invention showing a zero clearance fireplace including the cooling system of the present invention, wherein portions of the fireplace are removed to illustrate cooling air passageways and a passageway constricting baffle;
FIG. 2 is a cross-sectional side view, taken along line 2--2 of FIG. 1, of the zero clearance fireplace with cooling system;
FIG. 3 is a fragmentary front view of the zero clearance fireplace of FIG. 1 with a portion removed to illustrate the cooling system air passageway constricting baffle; and
FIG. 4 is a cross-sectional side view of an alternate embodiment of the present invention showing a differently configured zero clearance fireplace including a differently configured cooling system of the present invention.
Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate preferred embodiments of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1 and 2, there are respectively shown a fragmentary perspective view and a cross-sectional view of a zero clearance fireplace with a cooling system for the outer housing of the present invention. While the fireplace is shown and further explained herein with reference to a zero clearance, wood-burning fireplace product, the described embodiment is merely illustrative of one type of beneficial application of the present invention. The present invention is envisioned finding useful application with other fireplace units, for instance gas appliances, where the cooling of the outer housing effected by the cooling system is beneficial. In addition, the particular overall shape and construction of the zero clearance fireplace shown in not material to the present invention, and those of skill in the art will appreciate that an assortment of modifications to the fireplace can be provided while still utilizing the teachings of the present invention.
The zero clearance fireplace, generally designated 10, includes an outer shell or housing, generally designated 15, sized and shaped to closely fit within a building hollow which may be defined by combustible materials such as wood. Housing 15 is essentially formed of sealingly interconnected steel plates to provide front surface or wall 18, bottom wall 20, opposing side walls 22, 24, top wall 26, and rear wall 28. Housing top wall 26 includes an aperture through which flue 30 upwardly projects. Flue 30 can be installed in flow communication to a chimney stack of the building to allow products of combustion produced within fireplace 10 during operation to be exhausted to the outside atmosphere.
As shown in FIG. 1, an opening in front wall 18 for accessing the combustion chamber enclosed within housing 15 is covered with any suitable openable closure device known in the art, such as a standard set of transparent glass doors 34, 35 shown which are hingedly mounted in a well known manner. A series of individual elongate inlets or apertures 37, represented abstractly in FIG. 1, are provided in the bottom portion of front wall 18 and extend substantially the entire forward width of housing 15. Inlets 37 allow room air, as indicated by arrow 38 in FIG. 2, to be drawn into and serve to cool housing 15 in a manner described more fully below.
Referring now to FIG. 2, combustion chamber 45 and the associated products of combustion exhaust conduits are positioned internally of housing 15. Combustion chamber 45 is formed by bottom wall or floor 47, rear wall 49, top wall or ceiling 51, a far side wall 53, and an opposing side wall, not shown, all made of refractory materials. The opening in housing 15 covered by glass doors 34, 35 allows combustion air to be introduced or enter into combustion chamber 45 from the room in which fireplace 10 is installed. Combustion air could alternatively be provided through other openings or inlets, for example openings in the side walls of combustion chamber 45 connected by conduits to either room air or an outside air source. Grate 55, in which fuel such as wood logs 56 can be stacked and combusted to create products of combustion, is typically supported by chamber floor 47 and located at the center of the side-to-side width of combustion chamber 45. Additional fuel 56 can be added to grate 55 through the closure device covered opening. The initial flow path of the combustion products out of combustion chamber 45 is indicated generally by upward arrows 58 within chamber 45.
Referring now to FIG. 2, combustion chamber top wall 51 extends the full width of combustion chamber 45 near its rear region. Positioned forward of the rear region of top wall 51 is a ceramic fiber duct 60, described more fully in the parent application, which is inserted in an appropriately sized aperture in top wall 51. Duct 60 includes a rearwardly facing inlet 61, into which the products of combustion near the rear of the chamber and indicated at 58 are drawn, connected via a circuitous passageway to a horizontally disposed outlet 62. Duct 60 also includes a second duct portion positioned toward the front of combustion chamber 45. The second duct portion allows removal of products of combustion, referenced as 63, which may roll toward the front of combustion chamber 45 during operation.
Vertically aligned flue 30 is located above and in fluid communication with combustion chamber 45 and duct 60. Flue 30 projects upwardly from a combustion dome, generally designated 72, made of an aluminized steel plate. The two lateral edges and rear edge of combustion dome 72 are sealingly connected, such as by welding, to the top edges of right combustion casing 65 (See FIG. 1), a left combustion casing panel, not shown, and rear combustion casing panel 67 respectively, which are described more fully below. Combustion dome 72 includes a horizontal planar region 73 extending both forward and rearward of flue 30, an angled baffle region 74, and a forward flange 75 which may be connected in an air-tight manner to outer housing front wall 18. As shown in FIG. 3, a row of elongate openings 77 are provided along the length of flange 75. Combustion dome 72 and the regions of the combustion casing panels which upwardly extend above combustion chamber 45 cooperate to define chamber 80. Double angled diverter plate or bypass panel 82 is disposed within chamber 80 at a position beneath and in spaced apart relationship with combustion dome 72. Distal edge 83 of double angled diverter plate 82 juts rearwardly into the flow path of combustion products upwardly passing into flue 30, and plate 82 is particularly structured and arranged proximate the angled region of combustion dome 72 to create venturi passageway 85 therebetween within chamber 80.
In the embodiment shown in FIGS. 1-3, disposed at the upstream end of venturi passageway 85 is a cooling air baffle 86, with an upwardly extending rearward lip 87. Cooling air baffle 86, which extends the length of combustion dome flange 75 and is attached at its forward end to flange 75, prevents the cooling air flowing downwardly through openings 77 from passing directly into combustion chamber 45 and instead redirects this cooling air toward venturi passageway 85. Ending at a location rearward of openings 77, lip 87 is spaced from a coplanar region of double angled diverter plate 82 to define an opening 88 through which combustion products at arrow 63 enter venturi passageway 85. While the ratio of the size of opening 88 to the gap between lip 87 and flange 75 through which cooling air flows rearwardly may be varied within the scope of the invention, it will be appreciated that increasingly larger sizes of openings 88 decreases the amount of cooling air drawn through openings 77, which results in less cooling being pulled through the cooling passageways within outer housing 15.
In the shown embodiment, combustion chamber 45 is attached to and supported in spaced relationship above housing wall 20 by rear combustion casing panel 67 as well as similarly shaped and opposing right and left combustion casing panels 65. Only the right casing panel 65 is shown in the Figures. Panels 65, 67 are interconnected or possibly integrally formed aluminized steel plates that flank the opposing sides walls and rear wall 49 of combustion chamber 45. Combustion casing panels 65, 67 are secured along their lower edges to outer housing bottom wall 20.
The positioning of combustion chamber 45 above housing wall 20 defines lower plenum 90 therebetween. The shown spacing of the combustion casing panels 65 67 relative to outer housing 15 also creates a rear plenum 92 between outer housing rear wall 28 and rear combustion casing panel 67, a first side plenum 94 (See FIG. 1) between outer housing side wall 24 and right combustion casing panel 65, and an opposite side plenum, not shown, between outer housing side wall 22 and the left combustion casing panel. As shown in both FIGS. 1 and 2, a multitude of variously shaped and arranged holes 70 are provided through each of the combustion casing panels at a height below combustion chamber bottom wall 47. Holes 70 permit air drawn into lower plenum 90 through inlets 37 to flow into side plenum 94 and the opposite side plenum as indicated by arrows 95, as well to flow into rear plenum 92 as indicated by arrow 96.
Outer housing top wall 26 is in spaced apart relationship with combustion dome 72 so as to define upper plenum 98 therebetween above combustion chamber 45. Upper plenum 98 is, in other words, in fluid communication with rear plenum 92 as well as the side plenums. The above-described configuration of plenums achieves a number of cooling air passageways through which room air is drawn during fireplace operation to effect a cooling of the outer housing 15. For example, lower plenum 90, rear plenum 92 and top plenum 98 cooperate to form a generally C-shaped flow path for room air which during operation will cool the housing bottom wall 20, housing rear wall 28, and housing top wall 26. Side plenum 94, as well as the opposite side plenum, also cooperates with lower plenum 90 and top plenum 98 to form an air flow passageway for cooling air. While multiple, defined flow paths are shown herein, it will be appreciated that the cooling system can properly function to cool the upper outer housing with alternate or fewer cooling air passageways.
Referring to FIGS. 1-3, positioned within upper plenum 98 at the downstream or forward end thereof is upstanding baffle 100. Baffle 100 better promotes cooling of the forward portion of outer housing top wall 26 by effectively constricting the cross-sectional area of air flow of upper plenum 98 and forcing cooling air therein into contact with the outer housing as the air passes baffle 100. Vertically extending baffle 100 is attached at its lower end to combustion dome 72 at a location directly rearward of openings 77. The upper edge of baffle 100, which includes a rearwardly projecting lip 102 for rigidity, is spaced from the inner surface of outer housing top wall 26 to provide a slot shaped gap 104 therebetween. Cooling air indicated at 106 can pass through gap 104 into the compartment forward of baffle 100, and then pass through downwardly directed openings 77. It will be appreciated that the portion of the cooling air within upper plenum 98 which is the hottest and which has naturally migrated upwardly to the underside of housing top wall 26 will be forced through gap 104. Baffle 100 is preferably formed as a solid panel such that the entire volume of cooling air passing through upper plenum 98 must pass through gap 104. As shown in FIG. 3, baffle 100 spans substantially the entire width of upper plenum 98 and is transversely oriented to the flow of cooling air through upper plenum 98.
As best shown in FIGS. 1 and 3, further encircling the row of openings 77 are a pair of baffle flanges 108 which forwardly jut from the opposite lateral edges of the main body of baffle 100 to housing front wall 18. Flanges 108, which are coextensive in height with baffle 100, prevent cooling air from laterally circumventing baffle 100 and force the cooling air which reaches the flanges 108 from, for example, side plenum 94, to travel upwardly over the corner inner surfaces of outer housing 15.
A further understanding of the present invention will result from an explanation of its operation. When fuel 56 in grate 55 is combusted, the generated products of combustion primary pass upwardly as indicated by arrow 58, pass through inlet 61 and outlet 62 of ceramic duct 60, are directed rearwardly in chamber 80 by diverter plate 82, and then pass upwardly through flue 30. At the commencement of combustion, the cooling air within the passageways formed by the plenums between the outer housing and the combustion chamber is generally motionless. As combustion advances, the passing of the combustion products through chamber 80 and past plate edge 83 at arrow 84 creates a low pressure region at the downstream end of venturi passageway 85. Air thereby drawn or conveyed through passageway 85 creates a low pressure region at the upstream passageway end located proximate baffle lip 87. Cooling air baffle 86 establishes flow communication between venturi passageway 85 and openings 77, and consequently the low pressure region draws air within upper plenum 98 through openings 77 and through venturi passageway 85. Air drawn from upper plenum 98 is replenished by air from rear plenum 92 and the side plenums, which is replenished with air from lower plenum 90, which in turn draws air through inlets 37. An induced draft through the various cooling passageways formed by the plenums results. Due to the presence of opening 88, the low pressure of venturi passageway 85 also draws in the flow 63 of combustion products from chamber 45.
FIG. 4 discloses another embodiment of the present invention which is similar to the fireplace 10 shown in FIGS. 1-3 in most respects. Fireplace 110 includes a combustion chamber 45 defined in part by floor 47, rear wall 49 and top wall 51. In this embodiment, top wall 51 is formed of sheet-metal and defines an outlet through which the products of combustion are exhausted from combustion chamber 45 at a forward region of the chamber. Disposed exterior of combustion chamber 45 and interior of outer housing 15 is lower plenum 90, rear plenum 92 and upper plenum 98. Passageway constricting baffle 100, which is provided with lateral flanges, not shown, upwardly extends within upper plenum 98.
Mounted below plenum openings 77 for redirecting cooling air venting therefrom is a cooling air baffle assembly, generally designated 115. Baffle assembly 115 is basically the double angled diverter plate and stub shaped cooling air baffle of the embodiment of FIGS. 1-3 combined into a unitary structure into which combustion products do not enter or leak. Baffle assembly 115 is structured complementary to combustion dome 72 to define venturi passageway 116 therebetween. In this embodiment, passageway 116 is air-tight such that only a flow of heated room air which is circulated through upper plenum 98 and through openings 77 as indicated by directional arrow 118 is drawn through venturi passageway 116 by the low pressure region created within chamber 80 by the exhaust flow of combustion products. This flow of room air creates an induced draft through the cooling air passageways in a manner described above with respect to fireplace 10 of FIGS. 1-3. Air flowing through air passageway 116 mixes with combustion products and passes through flue 30 to be externally exhausted.
The underside of baffle 115 forms a passageway above the combustion chamber through which combustion products pass rearwardly into the flue 30. A vertically disposed diverter plate 120 may be also be provided to prevent combustion products from rolling forward into the room being heated and to cooperate with baffle 115 to route the combustion products rearwardly.
While this invention has been described as having preferred designs, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains. | A fireplace with a cooling air passageway within the fireplace housing that maintains the forward portion of the housing top wall cool during operation. The fireplace includes a combustion chamber, a flue, and an outer housing that encloses the combustion chamber. Plenums formed between the walls of the outer housing and the combustion chamber walls are used to circulate room air to keep the housing cool. Disposed within a forward portion of the upper plenum above the combustion chamber is a passageway constricting baffle. The baffle constricts the cross-sectional area of the upper plenum through which the cooling air flows and forces the cooling air flow upwardly against the underside of the housing outer top wall, thereby cooling this portion of the housing which typically is difficult to keep cool. The fireplace also includes a baffle which directs cooling air outlet from the upper plenum to a venturi passageway in communication with the flue. The baffle and passageway cooperate to induce a draft of cooling air through the upper plenum when access doors to the combustion chamber are either open or closed. | 5 |
This application is a 35USC371 of PCT/EP94/01050 filed Apr. 2, 1994.
BACKGROUND OF THE INVENTION
The present invention relates to novel pharmaceutical forms for oral administration capable of releasing active substances at controlled and differentiated rate. It is well known that the pharmaceutical forms for the oral administration are the overwhelming majority of the pharmaceutical market for numerous and diversified reasons which, in the case of tablets, are mainly determined in that they guarantee precise dosage, excellent stability of carried active materials and easy administration. In the last twenty years, of great importance has been the achievement of more and more sophisticated and diversified pharmaceutical forms, with the purpose of simplifying the posological scheme and obtaining greater patient's compliance. Such so called modified or controlled release pharmaceutical forms were aimed at, in the majority of cases, releasing the active material carried therein at constant rate in time, following a release kinetics defined as being of zero order.
In some cases it was also possible to highlight that, to a drug release at a constant "in vitro" rate, corresponded a more regular trend of plasmatic levels obtainable consequently to the administration to the patient.
If, in theory, such approach could have been correct so far as some drugs are concerned, in practice it has been noticed that, in many cases, the pharmacokinetics and pharmacodynamics of the active material in biological liquids are influenced and sometimes strictly determined by chronobiological rhythms. Furthermore, the developments of systems able to release the active material at constant rate has brought about the designing and therapeutical utilization of dosage forms more and more sophisticated that required the use of always new polymeric substances with specific properties from the technological and productive point of view. However, such polymeric materials, which are normally biocompatible are, not always biodegradable as well, and this implies that residues of these polymeric materials employed in creating grid therapeutic systems could remain in the organism and, above all, by repeated administration, cause unwanted accumulation phenomena.
In this respect, the setting in of now and then serious and, in some cases, lethal side effects occurred following the administration of the so called OROS system osmotic pump disclosed in the U.S. Pat. No. 4,160,020, 1979.
In the majority of cases, the slowing down of the active material release is obtained by utilizing gellable hydrophilic polymers capable of swelling in contact with water and/or aqueous fluids, thereby forming a gelled layer. From these systems the active material is in general released according to Fickiam type kinetics, A number of studies and research work have been carried out in the past and also recently aiming at the modulation of the release rate of active principles. This research was originated for therapeutic reasons (for instance the achievement of determined hematic and bioavailability levels of the drug) and because of practical problems related to the timing of the drug administration. Generally these studies to proposals consisting in two layer tablets, prevailingly of concentric type, and capable of a fast release of the active principle whereas the other was formulated so as to provide a slow or delayed releasing of the drug.
In some cases (WO-A-9305769 and EP-A-0384514) the outer layer is that with slow release, whereas the inner one (thus accessible only when the outer layer has fulfilled its function) is of the fast release type.
In other cases (U.S. Pat. No. 2,993,836 and U.S. Pat. No. 2,887,438) the delayed release layer forms the core of the tablet, whereas the outer coating layer is formulated for a fast or instantaneous release of a portion of the active principle.
According to further proposals two layer tablets have been disclosed in which the composition of the slow release layer was taken into consideration.
For instance in U.S. Pat. No. 2,951,792 the slow release layer consists of lipidic matrix formed by fatty alcohols or acids or more generally fatty derivatives. Besides the features relating to the formulation, particular attention is paid to the tablet size and to the extension of the area from which the release takes place.
In the two layer tablet disclosed in GB-A-2123291, the fast release part has a conventional composition, whereas that with slow release must contain at least one surface active ingredient.
Moreover the release delaying agent consists of a mixture of cellulose derivatives and of a slow solubilizing agent for the polymer mixture (particularly PEG). EP-A-63266 discloses a two layer composition (a fast release and a slow release layer) wherein exclusively sodium alginate is used as the release delaying agent. However the prior proposals were not satisfactory for several reasons, whereby it is still of interest the problem of the therapeutical cases wherein the administration (as acute or symptomatic treatment) of a first therapeutically effective dose of an active material is required, whereas in a following step the slow or at a lower rate administration of a maintenance dose of the same or different drug is necessary. These therapeutic needs obviously require complicated posological schemes that are not always correctly adhered to by the patient, especially if outpatient subjects are involved; it is well known in fact that non-compliance with posological schemes is directly proportional to the complexity and number of the daily required of recommended administrations.
In the case, for example, of rheumatic diseases, particularly for the night time pain treatment, it would be better to have the availability of pharmaceutical forms capable of a fast release of a dose of the drug for the so called acute treatment, whilst a second quantity should be slowly released, in order to maintain for a more prolonged period of time a plasmatic level sufficiently high and therapeutically effective. That is, during this second step the release of the active substance should occur at a rate comparable to that of the drug elimination (due to either the metabolism or normal biological elimination processes).
BRIEF DESCRIPTION OF THE INVENTION
The main object of the present invention is to solve the above explained problems and drawbacks, keeping unchanged the oral administration form by means of tablets. A more specific object of the present invention is a novel pharmaceutical form containing one or more active substances that can be released with different release kinetics and, namely, that such pharmaceutical form be designed and realized to meet the specific therapeutic requirements of particular pathological situations as those quoted in the introduction. The new form is in fact intended mainly of the administration of one or more drugs, one of which must act immediately, while a hematic level or a therapeutic activity for a more prolonged period of time is required for the second active substance (or for a portion of the same active substance).
These objects are achieved with the pharmaceutical form of the invention, which consists of a solid form having at least two layers of which:
at least a first layer contains an active material, carried with usual excipients and additives, that are able to promote the compressibility of the mass, in which the active material is distributed, such as to guarantee an immediate release of the active material, and
at least a second layer, superimposed upon the first one which, carries a portion of the same active material of said first layer or a second active material, the formulation of said second layer involving the use of excipients and adjuvants which can adjust the releasing rate of the active material at a definitely differentiated rate in comparison with that of the above mentioned first layer.
The novel formulation in accordance with the present invention allows, the use of well-established production technologies and to obtain the possibility of administering one or more active materials that are released by the pharmaceutical formulation with differentiated releasing rates.
The designed and realised system, as better pointed out by the examples supporting the present application, is intended for the administration of:
1- One drug only, released at different rates: one quantity immediately and a quantity within a prolonged and/or programmable period of time.
2- Two drugs, one of which is immediately released and the second one within a more prolonged period of time.
3- Association of two drugs, of which one quantity (drug 1+drug 2) is immediately released and one quantity (of both) over a prolonged period of time.
4- Three drugs, one of which is released fast, a second one which is released at a "in vitro" programmable speed in a longer period of time, and a the third one, that is released in an even more prolonged period of time.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail with reference to the accompanying drawings, in which
FIG. 1 shows an embodiment of the invention with two layers a and b;
FIG. 2 shows an embodiment with three layers a, b and c;
FIGS. 3-5 are graphs showing percentage release profiles;
FIGS. 6 is a graph showing plasma levels as a function of time.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
In preparing the different layers, besides the active material and depending on its solubility characteristics in water and/or aqueous liquids, polymeric materials capable of adjusting (slow down and/or accelerate) the active material release are also employed.
Among these substances of particular importance as regards the release rate are the so-called disintegrating and superdisintegrating polymers. Exhaustive information about these polymers are contained in the paper by Shangrow R, et el. Pharmaceutical Technology, October 1980, which is, incorporated herein by reference.
With regard to active materials sparingly soluble in water, particular adjuvants to facilitate a rapid solubilization can be used, such as cyclodextrins, superdisintegrators, etc., as reported in the book "Techniques of solubilization of drugs" by S. H. Yalkowsky Ed. M. Dekker, New York 1985, and in the Italian patent application No. 21091 A/90 of Jul. 20, 1990.
Active materials for the prevention of anginous attacks and hypertensive attacks, such as:
trapidil, diltiazem, verapamil, urapidil, or anti-inflammatory non steroidal (NSAID) or steroidal drugs: trapidil (7-diethylamino-5-methyl-1,2,4-triazol 1,5-a!pyrimidine), diltiazem hydrochloride (cis-(+)-3-acetoxy-5-(2-dimethylaminoethyl)-2,3-dihydro-2-(4-methoxyphenyl)-1,5-benz othiazepin-4(5H)-one hydrochloride), verapamil hydrochloride (5- N-(3,4-dimetheoxyphenethyl)-N-methylamino!-2-(3,4-dimethoxyphenyl)-2-isopropylv aleronitrile hydrochloride), Urapidil hydrochloride (6- 3-(4-o-methoxyphenylpiperazin-1-yl)propylamino!-1,3-dimethylpyrimidine-2,4(1H,3H)-dione hydrochloride)or non steroidal antiinflammatory drugs (NSSAID) or steroidal diclofenac sodium (sodium 2-(2,6-dichloroanilino)phenyl!acetate), indomethacin ( 1-(4-chlorobenzoyl)-5-methoxy-2-methylindol-3-yl!acetic acid), ibuprofen lysine salt (2-(4-isobutylphenyl)propionic acid compounded with L-2,6-diaminohexanoic acid acetate), ketoprofen (2-(3-benzoylphenyl)propionic acid), diflusinal (-(2,4-difluorophenyl)salicylic acid), piroxicam (4-hydroxy-2-methyl-N-(2-pyridyl)-2H-1,2-benzothiazine-3-caboxamide 1,1-dioxide), naproxen (+)-2-(6-methoxy-2-naphtyl)propionic acid), flurbiprofen (2-(2-fluorobiphenyl-4-yl)propionic acid) or sleeping substances and tranquillizers, such as diazepam (7-chloro-1,3-dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepin-2-one), nitrazepam (1,3-dihydro-7-nistro-5-phenyl-1,4-benzodiazepin-2-one) or antihistaminic and/or antiasthmatic drugs, such as ephedrine ((1R,2S)-2-methylamino-1-phenylpropan-1-ol hemihydrate), terfenadine (1-(4-tert-butylphenyl)-4- 4-(α-hydroxybenzhydryl)piperidino!butan-1-ol), teophhylline (3,7-dihydro-1,3-dimethylpurine-2,6(1H)-dione), chlorpheniramine ((±)-3-(4-chloro-phenyl)-NN-dimethyl-3-(2-pyridyl)propylamine hydrogen maleate) can be carried in the described pharmaceutical form.
As polymeric substances for the preparation of said for fast release layer of the active material, cross-linked polyvinylpyrrolidone, microcrystalline cellulose and cellulose derivatives, cross-linked sodium carboxymethylcellulose, carboxymethylstarch, potassium methacrylate-divinylbenzene copolymer, polyvinylalcohols, starches, starch derivatives, beta cyclodextrin and dextrin derivatives in general may be for example employed. Said polymeric substances make up from 10% to 90% of the layer's weight.
In said first layer other adjuvant substances may further find utilization, consisting of the so called effervescent mixtures, namely that can rapidly disintegrate the tablet or, in the specific case, the layer when it comes in contact with aqueous liquids and, preferably, with gastric juice.
These substances include the carbonates and bicarbonates of sodium and of other alkali metals or earth-alkali metals, the glycine sodium carbonate and other pharmaceutically acceptable salts, capable of producing effervescence in an acid environment.
Depending on the pH of the medium where the rapid disintegration of the compacted product should occur, further substances such as citric, tartaric, fumaric acids that can produce the effervescence and the rapid disintegration of the compacted product may find use in the formulation.
In the preparation of the slow release second layer, adjuvants may be used such as natural and/or synthetic polymeric materials belonging to the class of the so called hydrophilic gellable polymers, capable of slowing down the active material release from said layer.
The polymeric materials for the preparation of the slow release second layer may be selected in the class that includes hydroxypropylmethylcellulose of a molecular weight of between 1,000 and 4,000,000, hydroxypropylcellulose of a molecular weight of between from 2,000 to 2,000,000, carboxyvinylpolymers, polyvinyl alcohols, glucans, scleroglucans, mannans, xanthans, carboxymethylcellulose and its derivatives, methylcellulose and, in general, cellulose derivatives.
Of all the mentioned polymers various types are commercially available, characterized by different chemical, physical, solubility and gelling properties, in particular concerning hydroxypropylmethylcellulose, various types of different molecular weight (1,000 to 4,000,000) and different substitution degree can be employed.
Said hydroxypropylmethylcellulose types exhibit different characteristics, being prevailingly erodible or prevailingly gellable as a function of the viscosity in the polymeric chain. According to the solubility of the active material and of the hydration and/or erosion properties of the polymeric substance, different release and "in vitro" programmable rates could be achieved by suitable tests.
Said polymeric substances might be present in a percentage of 5 to 90% based on the total weight of said second layer but, preferably, from 50 to 85%.
Finally, excipients usually employed in the pharmaceutical technics can find application, such as mannitol, lactose, magnesium stearate, colloidal silica and others like glyceril monostearate, hydrogenated castor oil, waxes, mono-, bi- and tri-substituted glycerides.
Onto said finished tablets, a film of polymeric gastroresistant and enterosoluble material may be further applied, in order to allow the activation of the system only after the tablet has reached the duodenal-intestinal tract.
Pharmaceutical systems of this latter type might find use to make tablets specifically designed and intended to release the active material in the last part of the intestinal tract, namely at the colon level.
Cellulose acetophthalate, cellulose acetopropionate, cellulose trimellitate, acrylic and methacrylic polymers and copolymers, having different molecular weight and solubility depending on different pH values, may be used as polymeric materials for realizing gastroresistant systems.
Said gastroresistant and enterosoluble materials can be also utilized associated with retardant polymers.
Said gastroresistant and enterosoluble materials can be also utilized in combination with retardant polymers.
The pharmaceutical forms of the present invention allow therapeutic results and quite impredictable advantages to be reached as will be confirmed by experimental tests carried out both "in vitro" and "in vivo".
Referring for sake of description simplicity to the case wherein only one active material is administered either in the immediate release form or in that of programmed release, the pharmaceutical form of the present invention is likely to achieve the following results:
1) The immediate release of an amount of active material such as to set a plasmatic concentration equal to the minimum threshold needed for a symptomatic or active treatment; If, in the pharmaceutical forms for oral use with immediate release, a peak or maximum is reached in a time relatively closed to the administration arriving at a plasmatic concentration greater than the minimum required for a symptomatic therapeutic effect, this also means that with the new pharmaceutical form of the present invention the administered dosage is lower as compared to that usually estimated for the acute treatment.
Considering also that many of the drugs involved in the present invention, as for example the anti-inflammatory active principles, often exhibit high toxicity and are gastrodetrimental the important advantage thus achieved is clearly evident.
The slow or retarded release of the same active material starts when a plasmatic concentration, higher than that which can be achieved with the only slow release form is already secured, whereby higher plasma levels are obtained than those which can be achieved with only the slow release form, the time being the same from the beginning of the treatment.
Another aspect adds to such therapeutically important results, namely that the pharmaceutical form of the present invention is prepared by means of production technologies consolidated in the practice and presently used, whereby are directly applicable on industrial scale.
EXAMPLES
The following examples describe, by way of illustration and by no limitation whatsoever, the preparation of the pharmaceutical forms according to the invention.
Example 1
Two-layered tablet, containing 200 mg trapidil, one layer of which contains 50 mg for a fast release and the second slow release layer with additional 150 mg trapidil.
1-a Preparation of the granulate forming the first fast release layer, comprising as active material 50 mg trapidil.
______________________________________Trapidil (B.15910100) 50.0 mgLactose (C. Erba, Milan, I) 25.0 mgStarch maize (C. Erba, Milan, I) 15.0 mgPolyvinylpyrrolidone (Plasdone K29-32, 1.0 mgGaf Corp., Wayne, NY USA)Carboxymethylstarch (Explotab, Edward 10.0 mgMendell Co. Inc. Carmel, NY USA)Magnesium stearate (C. Erba, Milan, I) 2.0 mgTalc (C. Erba, Milan, I) 3.0 mgTotal 106.0 mg______________________________________
Trapidil, lactose and maize starch are mixed and wetted with a 10% polyvinylpyrrolidone solution in ethanol, followed by sieving on a 25 mesh sieve, drying so produced the granulate in an oven up to constant weight and sieving again on the same sieve. Carboxymethyl starch, magnesium stearate and talc are added, mixing thereafter in Turbula for 15 minutes.
A granulate (granulate A) is in this way made, showing good flow and compacting properties. The granulate undergoes the compression step as hereinafter described.
1-b Preparation of the granulate used to prepare the second layer containing 150 mg slow release trapidil
______________________________________Trapidil (B.15910100) 150.0 mgMannitol (C. Erba, Milan, I) 85.0 mgHydroxypropylmethylcellulose (Methocel K 4 M, 45.0 mgColocorn Orpinton UK)Polyvinylpyrrolidone (Plasdone K29-32, 7.5 mgGaf Corp., Wayne, NY, USA)Magnesium stearate (C. Erba, Milan, I) 1.5 mgColloidal silica (Syloid 244,Grace GmbH, Worms D) 1.5 mgTotal 290.5 mg______________________________________
Trapidil, mannitol and hydroxypropylmethylcellulose are mixed and wetted with a 10% ethanol solution of pyrrolidone.
After sieving on a 25 mesh sieve, so produced the granulate is dried in an oven at 40° C. up to constant weight and sieved again on the same sieve. The magnesium stearate and colloidal silice are added and mixed in Turbula for 10 minutes. With this procedure a granulate (granulate B) is obtained with good flow and compacting properties. The granulate undergoes the compression step as hereinafter described.
1-c Preparation of finished systems (by compression)
A Layer Press rotative compression machine (Manesty Liverpool U.K.) is, used to prepare tablets as shown in FIG. 1b; this machine as known by those skilled in the art, consist of a rotative compression mechanism equipped with two or three loading stations and thus able to make two or three layered tablets. In the specific case, the machine is assembled and set to produce two layered tablets. The machine for this purpose is equipped with oblong (capsule-type) punches of 16×16 min. The first loading hopper is filled with the granulate described at point 1-a (granulate A), while the second one is filled with the granulate described at point 1-b (granulate B). The First loading station is adjusted so as to provide layers of 106 mg granulate (equal to 50 mg active material) while the second loading station is adjusted so as to provide an amount of granulate B (slow release active material) of 290,5 mg equal to 150 mg active material.
By operating as previously illustrated, two-layered tablets, are produced weighing on average 396.5 mg which totally contain 200 mg trapidil. Said finished systems are subjected to the dissolution test as hereunder specified.
1-d Dissolution test
To evaluate the releasing features of the finished (two-layered) systems, the basket apparatus 1 (described in USP XXII) is utilized, operating at 100 r.p.m. and using as a dissolution fluid 1000 ml of deionized water at 37° C. The active material release is monitored by U.V. spectrophotometric determination at 299 nm, with an automatic system of sampling and quantitative determination, and with an automatic data processing program(Spectrocomp 602, Advanced Products-Milano) The test results are listed in Table 1
TABLE 1______________________________________Time (min) % released trapidil______________________________________15 27,030 37,560 45,3120 57,7240 75,5360 100,6______________________________________
It clearly appears that 25% of the 200 mg of the carried active material (first amount) is fast released in 15 minutes, whereas the second amount is released in about 6 hrs.
The data reported in Table I have been transferred in the FIG. 3 graph: to help in a comparison, FIGS. 4 and 5 report the graphs obtainable with the same dissolution test procedure, referred respectively only to the fast release form of 50 mg active material (that is of the trapidil itself) and only to the slow release form of 150 mg active material.
FIG. 6 shows the same release curves in just one graph, and it is easy to appreciate that, with the pharmaceutical form of the present invention, (curve a) an initial peak clearly higher than that attainable with the only form of retarded release is achieved, making it sufficient to add in the immediate release pharmaceutical form an active material concentration sufficient just to exceed the minimum threshold at which an immediate effect or, in other words of symptomatic treatment is attained to achieve the desired result.
In other words, from FIG. 6 it can be immediately appreciated that in the immediate release form (curve b) the 100% level of the active material release is quickly reached (within 15 minutes) and this makes to estimate that such a drug's quantity might be similarly absorbed attaining effective plasmatic concentrations. Likewise, in the case of administering the only one form of slow or retarded release (curve c), the total release occurs after a very long time, and therefore, a release level "in vivo" sufficient to produce a therapeutic effect will also be reached after a longer time.
Thus before the present invention, the therapeutical choice had to be made between adopting a symptomatic or shock therapy and a treating and maintaining therapy without, or at least with a poor symptomatic effect.
With the pharmaceutical form of the present invention comprising the two dosages of the immediate release and slow release forms respectively, as it is easy to verify from the corresponding curve (c) of FIG. 6, the release is about twice as much as that of the only slow release form, and is high enough to produce an immediate symptomatic effect.
Once this initial function is completed, the release takes place in the same way as with the slow release form, which consequently affect the release of the immediate release form.
An experimental confirmation of the previous "in vitro" tests has been obtained by carrying out the "in vivo" treatment in well being volunteers at the following dosages (and by plotting in FIG. 6 the corresponding plasmatic levels as a function of time):
(i) Fast release pharmaceutical form containing 100 mg of trapidil (curve b of FIG. 6) and
(ii) Slow release pharmaceutical form containing 200 mg of trapidil (curve c of FIG. 6) and
(iii) Pharmaceutical form according to the presente invention containing 200 mg of trapidil wherein the 25% of the active material dose was present as a fast release amount, and the remaining 75% was present as a slow release amount (curve a of FIG. 6).
The numerical data of the aforementioned plasmatic levels are listed in Table 1A which follows.
TABLE IA______________________________________Time Fast system 100 mg Slow system Fast/Slow system(hours) (ng/ml) 200 mg (ng/ml) 200 mg (ng/ml)______________________________________0.5 1015 482 17671 1969 762 27242 1464 1638 32053 1046 1479 28554 575 2058 28136 239 466 18158 76 421 130112 11 14 44024 8 0 0______________________________________
From Table 1A and FIG. 6 it can be immediately appreciated as the pharmaceutical form of the present invention makes it possible to reach the above mentioned therapeutic advantages, namely the effect of the symptomatic treatment (obviously by adjusting in a suitable manner the dosage of the fast release portion and that of ensuring that the slow release Form will maintain its effect.
In addition the symptomatic effect is obtained with a lower dosage of active principle (obviously calculated so as to exceed the threshold over which the acute effect is attained), with the clear advantages in terms of lower toxicity or, in the case of anti-inflammatory non-steroidal drugs (FANS), lower gastrolesiveness besides a minor quantity administered to the patient.
Example 2
--Two--layered tablet containing 400 mg of 4-methoxy-N3-(3-pyrimidilmethyl)1,3-benzenedicarboxamide (compound hereinafter indicated with G619), of which one layer contains 200 mg of active material for a fast release and in a second layer there are 200 additional mg of G619 for slow release.
2-a Preparation of the granulate forming the first fast release layer, containing 200 mg of G619 as active material.
______________________________________G 619 (Farma resa batch n. 89043 200.00 mgMaize starch 75.00 mgMannitol 25.00 mgPolyvinylpirrolidone (10% in ethanol) 6.25 mgCarboxymethylstarch (Explotab) 10.00 mgMagnesium stearate (C. Erba) 3.75 mgColloidal. Silica (Syloid 244) 0.75 mgTotal 320.75 mg______________________________________
2-b Preparation of the granulated used for preparing the second slow release layer wherein 200 mg of G619 are contained.
______________________________________G 619 (Farma resa batch N. 89043) 200.0 mgMannitol (C. Erba, Milan, I) 50.0 mgHydroxypropylmethylcellulose (Methocel K 4 M, 30.0 mgColorcon, Orpington UK)Hydroxypropylmethylcellulose (Methocel E 5, 30.0 mgColorcon, Orpington UK)Polyvinylpirrolidone (Plasdone K29-32, 13.0 mgGaf Corp, Wayne NY USA)Magnesium Stearate (C. Erba, Milan, I) 2.5 mgColloidal Silica (Syloid 244, Grace GmbH, 0.5 mgWorms, D)Total 326.0 mg______________________________________
Both these layers are prepared as per Example 1.
2-c Preparation of the finished systems (by compression)
The same rotative compression machine, equipped with oblong (capsule-type) punches of 19×9 mm, as described in Example 1, is used to prepare the tablets. The first loading hopper is filled with the granulate described at point 2-a (granulate A), while the second one is filled with the granulate described in 2-b (granulate B). The first loading station is adjusted in order to provide layers of 320,75 mg of granulate (equal to 200 mg active material), while the second loading station is adjusted so as to provide an amount of granulate B (with slow active material release) of 326.0 mg equal to 200 mg active material.
By operating as previously illustrated, two-layered tablets with an average weight of 646,75 mg, totally containing 400 mg of G619, are produced.
Said finished systems are subjected to the dissolution test as hereunder specified. 2-d Dissolution test
To evaluate the releasing features of the finished (two-layered) systems, the 2 paddle apparatus (as per USPXXII) is used, operating at 100 r.p.m. and with 1000 ml at 37° C. of deionized water used as a dissolution fluid. The active material release is monitored by U.V. spectrophotometric determination at 251 nm, with an automatic system of sampling and dosage, as well as with an automatic data processing program (Spectracomp 602, Advanced Products Milano).
The results of the tests carried out are listed in Table II.
TABLE II______________________________________Time (min) % Released G619______________________________________15 53,030 58,560 65,0120 78,2180 90,3240 98,5360 100,4______________________________________
It is evident that of the 400 mg of the carried active material, 50% (first amount) is fast released, in 15 minutes, whereas the second amount is released in about 4-6 hours.
Example 3
Two layer tablet containing 800 mg of ibuprofen, one fast release layer containing 250 mg of active principle and the other slow release layer containing 550 mg of ibuprofen.
3-a Preparation of the granulate forming the first fast release layer containing as the active principle 250 mg of ibuprofen.
______________________________________Ibuprofen (CFM B. 2235/18/87) 250.00 mgMaize starch (USP grade, C. Erba, Milan, I) 74.63 mgDye (Nacarat Red E 120) 0.25 mgMethylcellulose (BDH, Poole, UK) 1.25 mgSodium laurylsulfate (C. Erba, Mllan, I) 0.75 mgCarboxymethylstarch (USP grade) 18.75 mgCrosslinked polyvinylpyrrolidone 7.50 mg(Polyplasdone XL, ISP, Wayne, US)Magnesium stearate (C. Erba, Milan, I) 3.37 mgTotal 356.50 mg______________________________________
The manufacturing process comprises the preparation of a granulate obtained by admixing, in a sigma mixer (Erweka model type K 5, Frankfuert a.M., D) the proper amounts of active principle and 50 mg of maize starch; the homogeneous powder mixture is wetted with a 1.3% (w/v) aqueous solution of methylcellulose in which the sodium laurylsulfate and the dye have been previously dissolved; the homogeneously moistened mass is forced through a 25 mesh (710 um) grid leading to a regular granulate which is dried in an air circulation oven at 40°-45° C. The granulate, after drying to constant weight, is placed into a powder mixer (Turbula mod.T2A, Bachofen, Basel, CH), added with the crosslinked polyvinylpyrrolidone, the remaining 24.63 mg of maize starch and the carboxymethylstarch and admixed for 20 minutes. Then the magnesium stearate is added and the admixing is continued for further 20 minutes. The granulate, lubricated and analyzed for the content of active principle, is subjected to the hereinafter described compression phase.
3-b Preparation of the granulate used for the second slow release layer containing 550 mg of ibuprofen.
______________________________________Ibuprofen (CFM B. 2235/18/87) 550.0 mgHydroxypropylmethylcellulose 183.3 mg(Methocel K4K Colorcon, Orpington UK)Mannitol (C. Erba, Milan, I) 110.0 mgPolyvinylpyrrolidone (Plasdone 18.3 mgK 29 ISP, Wayne, NY USA)Talc (C. Erba, Milan, I) 16.5 mgMagnesium stearate (C. Erba, Milan, I) 3.7 mgColloidal silica (Syloid 244, 0.9 mgGrace GmbH, Worms D)Total 882.7 mg______________________________________
A granulate is preparaed by admixing in a sigma nixer (Erweka model type K5) the proper amounts of ibuprofen, mannitol and hydroxypropylmethylcellulose (Methocel K4M, apparent viscosity 4,000 cP); the homogeneous powder mixture is wetted with a 10% (w/v) alcoholic solution of polyvinylpyrrolidone and the homogeneously wetted mass is forced through a 25 mesh grid leading to a regular granulate which is dried in an air circulation oven at 40°-45° C. The granulate, dried to constant weight, is placed in a powder mixer (Turbula model T2A) and added with talc, magnesium stearate and colloidal silica, and admixed for 20 minutes. The granulate is then compressed as hereinafter described.
3-c Preparation of the finished systems (by compression)
For the preparation of the tablets the same rotating compression machine and the same operating conditions as in the previous examples are used, so as to obtain two layer tablets.
The resulting tablets have an avenge weight of 1239.2 mg containing on the whole 800 mg of ibuprofen, which are subjected to the dissolution test as hereinafter specified.
3-d Dissolution test
In order to assess the realeasing behaviour of the tablets the 2 paddle apparatus is used (USP XXII) adjusted for a vessel of 5 liters capacity in order to maintaining the sink conditions, the test being carried out at 100 r.p.m. and using as the dissolution fluid 5 l of simulated intestinal fluid (USP XXII), without enzymes at 37° C. The release of the active principle is monitored by U.V. spectrophotometric measurement at 223 nm, using an automatic sampling and reading system (Spectracomp 602 of Advanced Products, Milano, I).
The results of the test are reported in the following table III
TABLE III______________________________________time (h) Released % (total)______________________________________0.5 31.32 37.04 42.98 52.912 66.216 78.520 88.024 99.1______________________________________
It is thus seen that from the tablets the fast release of the first amount of drug (about 31% of the total) is obtained within 30 minutes, whereas in the second phase, definitely differentiated from the first one, the drug is released under controlled rate in about 24 hours.
The foregoing examples refer to pharmaceutical forms containing only one active material divided within two layers.
It is understood that is also possible and foreseen within the scope of the present invention to produce, with the above mentioned procedures, three-layered pharmaceutical forms, that is with delayed release of the same active material but adjusted at different rates from one layer to another.
Similarly, the third layer might instead include another active material for supplementing, at a certain point of the treatment, the therapeutic effect of the first active material, already released in fast and/or slow released form as well.
So far the realisation of the aforementioned pharmaceutical forms is concerned, these are made with the galenical technics already cited, and by employing the adjuvants and carriers well known by themselves in the technical field.
It should be finally noted that the previous list of the active materials which can be used in the pharmaceutical forms of the present invention is not intended as a limit since, as it is evident, the invention is extended to all the active materials, for which is foreseen or foreseable either the fast release administration for a systemic therapeutic effect or the slow release administration for a treatment of maintaining or prolonging the main therapeutical effect. | Multilayered controlled-release solid pharmaceutical composition in tablet form suitable for oral administration comprising at least two layers containing active material in association with excipients and additives. One layer of the tablet releases a portion of the drug quickly while the other layer and optionally further layers release portions of the drug more gradually. | 0 |
SUMMARY OF THE INVENTION
This invention relates to a pipe joint comprising a joint body, packing members inserted within the joint body for sealing the connected pipes, and a presser ring for closely pressing the packing members against the outer peripheral surface of the pipes to insure that the packing members may perform their sealing function accurately.
Conventionally, pipe joints of a variety of constructions have been proposed. The present invention, however, is characterized in that there is provided a peripheral groove on the outer surface of the pipe to be connected, in which groove is mounted an O-ring which is to be fastened to the joint body by means of a presser ring through a counter ring so that the pipes are accurately connected and, furthermore, they are supported by two pieces of rubber packings each inserted thereon so that they are provided with flexibility and operated very simply and no leakage nor turbulence of fluid occurs at the point of connection.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings show one preferred embodiment of a pipe joint according to the present invention, in which:
FIG. 1 is a side view of the pipe joint with its half portion being cut off;
FIG. 2 is a side view thereof when fastened together; and
FIG. 3 is a sectional view along the line A--A' in FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to improvements in or relating to a pipe joint.
The invention comprises a tubular joint body, packings to be inserted within the body, and a presser ring for pressing the packings closely against the outer peripheral surface of the pipe to be connected, said joint body having a step means for receiving the end of a pipe to be connected in such a fashion that the inner diameter of the joint body and that of the pipe to be connected may coincide with each other and, furthermore, the joint body is provided, adjacent to the step means, with an enlarging slant portion forming a gap between this slant portion and the pipe inserted into the joint body, positioning said packings within the gap and pressing the packings with the presser ring member.
Now, a preferred embodiment of the pipe joint of this invention will be described in detail with reference to the accompanying drawings.
In the drawings, 1 is a tubular pipe joint; 2 and 3 are packings; 4 is a presser ring member for the packings 2 and 3; and 5 is a pipe to be connected.
The tubular body 1 is provided with a step means 6 for abutment of the pipe 5 thereto. Through the portion of this step means 6 the inner diameter of the pipe 5 and that of the joint body 1 are in coincidence with each other so that any turbulence of fluid flowing therein is avoided.
Also, the body 1 is provided, adjacent to the step means 6, with an enlarging slant portion 7 which, together with the pipe 5 inserted into the body 1, provides a gap 8 within the inner peripheral surface of the body 1.
Within this gap 8 there are positioned the packings 2, 3 that are inserted onto the pipe 5, and between the packings 2 and 3 there is provided a counter ring 9 for pressing against the O-ring 11 which has a cut therein to render itself flexible and which is inserted in the peripheral groove 10 provided on the surface of the pipe 5. The packings 2 and 3 are arranged to be pressed by the presser ring 4 with its flange 12 being fastened with the flange 13 of the end edge of the body 1 with the bolt 14, the fastening force of which presses the packings closely against the pipe.
According to the present invention, any turbulence of the fluid flowing through the connected pipes is avoided since the inner diameter of the joint body and that of the connected pipes coincide with each other. Also, any fluid leakage is completely prevented because of the packings being closely pressed against the pipe by the counter ring member. In addition, the connecting operation is very easy and the invention has thus a great economical value. | A pipe joint with which pipes are securely connected through very simple operation so that the pipes will not come out after they have been connected and the joint is flexible, permitting no leakage of fluid flowing therein. | 5 |
The present application is based on and claims priorities of Japanese patent applications No. 2008-304020 filed on Nov. 28, 2008, No. 2008-304024 filed on Nov. 28, 2008 and No. 2008-309521 filed on Dec. 4, 2008, the entire contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to drawer type cooking devices having a turntable mechanism for heating an object to be cooked in a uniform manner.
The present invention also relates to drawer type cooking devices, wherein a drawer body with a door loading therein an object to be cooked is placed in the interior of the cooking device body and capable of being drawn out therefrom.
2. Description of the Related Art
In the prior art, cooking devices having a drawer body formed integrally with a door and capable of being drawn out to the front side of the cooking device have been proposed. Since this type of drawer type cooking devices can be built into the kitchen cabinet arranged downward of a countertop of a kitchen and installed without occupying the countertop area, it is suitably applied to a kitchen arrangement where multiple cooking devices are disposed spatially. Therefore, drawer type cooking devices have been considered as one type of cooking devices installed in a fitted kitchen or designed kitchen, and the use thereof is spreading especially in the United States.
FIG. 17 shows a perspective view of one example of a cabinet structure to which the cooking device is built in. There are two standard sizes for the width W of the mounting portion of the cabinet, which are 24 inches (approximately 62 cm) and 30 inches (approximately 76 cm). The height of the cabinet is 914 mm, the mounting surface height of the cooker is 483 mm, and the width, height and depth of the opening for loading the cooking device are 721 mm, 375 mm and 597 mm, respectively. The withstand load of the mounting surface is 160 kg or greater. A power supply outlet is disposed at a rear wall of the mounting opening portion. Since drawer type cooking devices have a common heating chamber width formed in the interior thereof and a common drawer body width, the drawer type cooking devices will correspond to the cabinet structure by changing or selecting the width of the door and the width of the outer casing.
The present applicant has proposed in patent document 1 (Japanese patent application laid-open publication No. 2005-221081=Publication of Japanese patent No. 4027325) a drawer type microwave oven as an example of a drawer type heating cooker, comprising a cooking device body having a heating chamber, a drawer body movably disposed within the cooking device body and capable of being drawn out of the heating chamber of the cooking device body, and slide rails for moving the drawer body within the cooking device body, wherein the slide rails are disposed outside the heating chamber, according to which the slide mechanisms can be formed without using components or materials having high heat resistance and flame resistance, and defective discharge via the microwaves can be prevented.
Since the prior art drawer type microwave oven disclosed in patent document 1 (Japanese patent application laid-open publication No. 2005-221081=Publication of Japanese patent No. 4027325) has slide mechanisms disposed on the side wall and the bottom wall of the heating chamber on the outer side of the heating chamber for moving the drawer body linearly, it is difficult to supply the microwaves generated via a high frequency generator through the side wall or the bottom wall of the heating chamber. Therefore, the arrangement adopts a ceiling power supply structure in which a waveguide for introducing microwaves is disposed on a ceiling portion of the body on the outer side of the heating chamber, and microwaves are supplied through the waveguide into the heating chamber.
On the other hand, general mass-produced microwave ovens to be placed on a kitchen counter-top include a turntable-type microwave oven in which a rotating turntable is disposed on the bottom side of the heating chamber as a uniform heating mechanism for heating an object to be heated such as food in a uniform manner, and a turntable having the object to be heated mounted thereon rotated during heating operation. Further, general mass-produced drawer type microwave ovens not capable of adopting turntables adopt a rotating stirrer or a rotating antenna-type microwave oven in which a rotating body having a nonuniform shape such as a metal plate is disposed within the microwave path on the ceiling portion, and the rotating body is rotated during heating operation so as to stir the microwave distribution within the heating chamber.
In order to adopt a turntable as a uniform heating mechanism in drawer type microwave ovens, a rotating turntable must be disposed on the drawer body. However, it is difficult to dispose a driving mechanism to a linearly-movable drawer body and to supply power thereto, and it is also difficult to arrange the turntable and the driving mechanism thereof within the vertically narrow space. Therefore, a rotating antenna as a uniform heating mechanism was arranged within the waveguide disposed on the ceiling surface of the heating chamber, which is a fixed area. In order to adopt this type of uniform heating mechanism, it was necessary to adopt a ceiling surface power supply structure for supplying microwaves through the ceiling into the heating chamber.
However, there have been strong demands from users favoring the traditional turntable structure for a drawer type microwave ovens adopting a turntable enabling to visually confirm the heating operation of the microwave oven. Further, according to a survey carried out by the present applicant to users of drawer type microwave ovens in the United States, it was discovered that many consumers desired the turntable mechanism to be adopted in microwave ovens.
On the other hand, according to another survey, it was discovered that there were strong demands for the ceiling height of the heating chamber of the drawer type microwave oven to be 180 mm or higher, so as to enable mugs of a famous coffee shop chain to be easily placed therein. Therefore, to set the ceiling height of the heating chamber to 180 mm or higher is a priority matter in designing the drawer type microwave oven.
As described, adopting turntables in drawer type microwave ovens has been a top priority technological challenge from the start of development of the drawer type microwave ovens, but it has not been possible for a long time.
One possible structure for adopting a turntable in a drawer type microwave oven is to first dispose a turntable on a bottom surface of the drawer body similar to the prior art microwave oven, and to dispose a rotary motor below the bottom surface of the drawer body as driving mechanism. According to such structure, the rotary motor moves together with the movement of the drawer body, so the mechanism does not require special engagement and disengagement operations.
However, since the area below the bottom surface of the drawer body is arranged within the heating chamber of the microwave oven into which microwaves are irradiated, it is impossible to dispose a rotary motor therein. Thus, it is impossible to dispose a turntable having the prior art structure to the drawer type microwave oven.
Further, since the power line connected to the rotary motor is moved and bent every time the drawer body is drawn out of or pushed into the heating chamber, it is extremely difficult to ensure the durability of the power line.
In order to solve the problems mentioned above, an engagement-disengagement mechanism must be adopted in which the driving unit requiring power supply such as the rotary motor is left in the main body and the turntable having food loaded thereon is moved together with the drawer body, wherein the driving unit and the turntable are engaged and disengaged by the movement of the drawer body.
One idea of such engagement-disengagement mechanism is a magnet coupling capable of transmitting power in a noncontact manner.
The present applicant has proposed (refer to patent document 3: Japanese patent application laid-open publication No. 2004-071213) a cooking device adopting a uniform heating mechanism for rotating a turntable via the drive force of a rotary motor disposed outside a casing by utilizing the magnetic coupling of a first magnet in the turntable and a second magnet in the drive mechanism in a general microwave oven. When the rotation mechanism proposed here is assembled in a drawer type cooking device, even without considering the cost of the magnet, there is a drawback in that a problem occurs in the operation of the drawer type cooking device.
That is, since the magnet coupling is linked magnetically in the perpendicular direction corresponding to the direction of the rotary shaft, the drive mechanism portion and the rotary operation portion are strongly attracted to each other in the perpendicular direction when the drawer body is to be opened, and a large load is applied to the movement mechanism moving in the direction orthogonal to the rotary shaft for moving the drawer body in the horizontal direction, according to which the drive force must be increased and smooth draw-out operation cannot be performed. Thus, from the viewpoint of cost and reliability, the magnet coupling could not be applied to drawer type microwave ovens.
Further, an engagement-disengagement mechanism for moving the turntable in the perpendicular direction is also considered as another example of the engagement-disengagement mechanism.
Such engagement-disengagement mechanism requires an anticollision means for the upward movement of the turntable when moving the receiver in the frontward direction. As a result, a limitation must be set to the height of the food and the like, and the ceiling height of the heating chamber is thus substantially lowered. Therefore, it is difficult to adopt an engagement-disengagement mechanism that moves the turntable in the perpendicular direction.
The present applicant has proposed in patent document 2 (Japanese utility model registration No. 2520881) a cooking device having a round turntable with a rotating body disposed near the circumference of the bottom surface of the turntable, a driven shaft fixed to the center portion of the bottom surface of the turntable passing through the receiver and having a driven gear fixed to the lower end thereof, the turntable rotatably mounted on the receiver, wherein the driven gear is engaged with a drive gear fixed to an end of the rotary shaft of the turntable driving motor when the door is closed, and the driven gear is disengaged from the drive gear when the door is opened and the receiver is moved in the frontward direction.
According to the cooking device, the drive gear and the driven gear are bevel gears that are widened toward opposite directions, and the gears are required be engaged when the door is closed in order to operate. In order for the gears to accurately encounter each other and to be accurately engaged with one another each time the door is repeatedly opened and closed, not only a very high component accuracy and assembly accuracy unprecedented in the prior art cooking device is required, but also the abrasion and deformation of the respective components caused by repeatedly opening and closing the door must be reduced significantly so as to maintain constant dimension and constant engagement. It is difficult to adopt such engagement-disengagement mechanism.
Even if one of the above-mentioned mechanisms is adopted, since the movement mechanism must be mounted on the outer side of the bottom portion of the heating chamber in order to support the weight of the door and the drawer body having food loaded therein according to the prior art drawer type microwave oven, the drive mechanism of the turntable cannot be extended downward from the heating chamber, and since microwaves are distributed also in the space between the drawer body and the heating chamber, it was difficult to dispose the motor composed of metallic components therein, so the installation of the drive mechanism became a problem.
As described, since adopting a turntable having an engagement-disengagement mechanism in the cooking device was a common challenge for those in the field of art, many studies have been performed related to various design options.
Further, U.S. Pat. No. 5,796,802 proposes a microwave oven having a division plate with multiple turn trays disposed within a heating chamber. This microwave oven has division plates mounting turn trays inserted horizontally in the heating chamber of the microwave oven, and the turn trays are attached removably to the division plate. A mechanism for rotating the turn trays adopts a rim (outer circumference) drive structure, having a gear disposed on a rotary shaft extending in the perpendicular direction of the drive motor disposed at the depth portion of the heating chamber, and the tray disposed on the division plate has a rotary teeth portion revolving at the lower rim portion of the tray, wherein the motor applies drive force to the rotary teeth portion to rotate the turn tray. If the division plate is attached to the depth portion of the heating chamber, the gear and the rotary teeth are mutually engaged, and the turn tray can be rotated via the motor. If the division plate is moved to the frontward direction, the gear and the rotary teeth are disengaged, so the turn tray will not be rotated. The rotary teeth portion has a relatively large radius so that a gentle cylindrical curved surface is formed, and it is tolerant to the positional dispersion with respect to the gear in the horizontal direction. Further, the gear and the rotary tooth portion can be engaged via friction transmission engagement instead of gear engagement.
However, as obvious to the engineers in this trade, turn trays for cooking devices of reasonable prices are almost without exception designed and manufactured for attaining lowest cost, not for high precisions. It is therefore deduced, according to this microwave oven, that the rotary teeth portion at a radial distance of approximately 15 cm from the center of rotation has a dimensional dispersion of a few mm from the center of rotation. Thus, when the turn tray is rotated, the rotary teeth portion and the gear repeatedly collide against one another generating noise and vibration, so it may be necessary to take measures to prevent separation for example by pressing the turn tray toward the depth direction via an elastic body. Moreover, if the turn tray is reduced in size due to the individual dimensional fluctuation of the turn tray, which often overwhelms manufacturer's control, there always are risks that the rotary teeth portion may not be engaged with the gear. However, the attempt to improve the dimensional precision of the turn tray in order to overcome this problem will result in the increase of cost.
Further, in order for the turn tray to be engaged to the gear in a disengageable manner, an opening must be formed to the engaged portion between the gear at the depth wall surface of the heating chamber and the rotary teeth portion. Thus, boiled over water or the like may flow downward through the opening. Drawer type cooking devices must have a space between the depth of the drawer body and the depth wall of the heating chamber for disposing the gear. Such arrangement is considered to create a drawback in that the depth of the drawer body is narrowed, by which the storage space for loading the object to be heated is also narrowed.
When drinks are to be heated in a drawer type microwave oven, drink containers are loaded in the drawer body drawn out of the heating chamber, but the heights thereof differ, and high narrow containers are intentionally formed by some designers. In order to store such high containers in the heating chamber, the height of the heating chamber must be increased, and if the microwave oven adopts a ceiling surface power supply structure, the ceiling height of the whole microwave oven body must necessarily be increased.
According to the prior art drawer type microwave ovens, power supply structures including the waveguide and uniform heating mechanisms such as a rotary antenna mechanism are disposed on the ceiling, and the ceiling must provide space for arranging such mechanisms. However, since the built-in space in which such drawer type microwave ovens are installed has a strict height limitation within the fitted kitchen or designed kitchen structure, it is actually impossible to increase the exterior height of the drawer type microwave ovens. Since the overall height of the microwave ovens was restricted, it was difficult to respond to the size-related demand of the object to be heated.
A cooking method using a thermal shock system in which high-temperature air heated via a heater is collided at high speed against an object to be cooked through an air blower is known. The present applicant proposes (refer to patent document 4: Publication of Japanese patent No. 3939232) a cooking device comprising a heating chamber for storing an object to be cooked, a heating means for heating the object to be cooked within the heating chamber, an air blower means for introducing hot air of the heating means into the heating chamber, and a control means for controlling the heating means and the air blower means, wherein the hot air via the heating means is blown into the heating chamber via multiple air blow paths and air supply outlets, and a control means controls the heating means and/or the air blower means and performs cooking via multiple circulating hot air systems by selecting and combining multiple air blow paths, thereby enabling a single cooking device to perform multiple cooking operations via selecting and combining the multiple air blow paths. Therefore, a single cooking device enables to perform multiple cooking methods, such as a cooking method preferable for high speed heating for cooking pizza or a lump of meat such as roast chicken, in which the heat transfer of the surface of the object to be cooked is improved by the wind pressure of the thermal shock, and a normal speed cooking method preferable for cooking an object to foam the same, such as baking a sponge cake, or for cooking an object containing much air.
It is difficult to introduce the hot air cooking function to the prior art drawer type microwave oven to obtain a composite cooking device. One reason for this is that the prior art drawer type microwave oven adopts a ceiling surface power supply structure, so that the uniform heating mechanism adopting a waveguide and a rotary antenna must be arranged on the outer space on the ceiling of the heating chamber, and attaching heat insulating materials required for hot air cooking is difficult. Another reason is that a high-speed hot air heating cooker suitably assembled as a high speed heating function to the microwave oven requires a uniform heating mechanism such as a turntable in which the object to be heated is moved within the heating chamber, so that it cannot easily be assembled to the prior art drawer type microwave oven adopting a rotary antenna instead of a turntable.
Moreover, the cooker with a high speed hot air cooking device proposed in patent document 4 (publication of Japanese patent No. 3939232) assumes a consumption power exceeding 2000 W since the specification thereof realizes a high speed cooking operation corresponding to or exceeding the cooking operation using a gas oven, and has a large-capacity heating chamber. Therefore, in order to adopt the high-speed hot air cooking function in a drawer type cooking device built into a kitchen and assuming a consumption power of approximately 1200 W, it is necessary to reduce the consumption power and improve the heat radiation performance.
SUMMARY OF THE INVENTION
The problem to be solved in the drawer type cooking device having a drawer body capable of being drawn out of a heating chamber is to provide a uniform heating mechanism via a turntable to the drawer body and to perform smooth transmission and disconnection of power between the turntable and a motor disposed outside the heating chamber corresponding to the drawing out and storing of the drawer body with respect to the heating chamber.
The object of the present invention is to provide a drawer type cooking device capable of rotating the turntable on the drawer so as to heat the object to be cooked in a uniform manner and prevent uneven heating caused by the position and the posture of the object within the heating chamber, and to prevent the increase of height of the device by discarding the prior art rotary antenna and the confirmation means for electronically or optically detecting the rotation status of the rotary antenna.
Another problem to be solved in the drawer type cooking device is to arrange a power feeding structure and a uniform heating mechanism using the outer space on the sides and bottom areas of the heating chamber instead of the ceiling surface power supply structure and the uniform heating mechanism disposed on the ceiling.
The object of the present invention is to solve the problems mentioned above by eliminating the ceiling power supply structure using the waveguide and the uniform heating mechanism such as the rotary antenna mechanism disposed on the ceiling, thereby providing a drawer type cooking device capable of increasing the ceiling height of the heating chamber as much as possible without increasing the overall height of the cooking device.
The present invention provides a drawer type cooking device having a drawer body capable of being stored into or drawn out of a cooking device body having a heating chamber formed in an interior thereof, wherein a door of the drawer body closes a front side opening of the heating chamber when the drawer body is at a stored position; the cooking device comprising: a turntable supported rotatably on a bottom wall of the drawer body; a motor disposed outside the heating chamber at a bottom wall portion of the cooking device body; and a power transmission mechanism disposed between the bottom wall portion of the cooking device body and the bottom wall of the drawer body, being engaged when the drawer body is pressed into the cooking device body and disengaged when the drawer body is drawn out of the cooking device body, capable of transmitting a rotation of the motor to the turntable when engaged; the power transmission mechanism comprising: a first transmission unit attached to an output shaft of the motor passing through the bottom wall portion of the cooking device body and protruding into the heating chamber; a second transmission unit attached to a rotation shaft of the turntable passing through the bottom wall of the drawer body and protruding into the heating chamber; and a sector-type transmission unit disposed pivotally on the cooking device body, constituting a first engagement portion on an outer radial side being engaged with the power transmission unit and also constituting a second engagement portion on an inner radial direction opening toward a draw-out direction of the drawer body and engaging with the second transmission unit when the drawer body is at a stored state.
According to the drawer type cooking device of the present invention described above, it is possible to rotate the turntable on the drawer body capable of being drawn out of the cooking device body so as to heat the object to be cooked in a uniform manner and eliminate uneven heating caused by the position of the object within the heating chamber. The prior art rotary antenna is no longer necessary, and thus, the confirmation means such as an electronic or optical rotation detecting means for confirming the rotation status of the rotary antenna visually and detecting the stopping of the rotary antenna in order to prevent the occurrence of uneven heating is no longer necessary. Furthermore, since the rotary antenna is unnecessary, the height of the cooking device will not be increased.
In order to achieve the above-mentioned objects, the present invention further provides a drawer type cooking device having a drawer body capable of being drawn out of or stored in a cooking device body having a heating chamber formed in an interior thereof, wherein a door of the drawer body closes a front side opening of the heating chamber when the drawer body is at a stored position; the cooking device comprising a turntable and a driving mechanism thereof disposed with respect to a bottom wall of the drawer body, and a side wall power supply structure disposed within a side wall space on the outer side portion of the heating chamber.
According to the present drawer type cooking device, a side wall power supply structure is adopted as the power supply structure for supplying microwaves into the heating chamber, and arranges the turntable and the drive mechanism thereof with respect to the bottom wall of the drawer body as a uniform heating mechanism, so that the ceiling does not have the power supply structure and the uniform heating mechanism arranged thereto. The waveguide for guiding the microwaves generated via the high frequency generating device for generating microwaves is arranged on the side wall space on the outer side portion of the heating chamber and constituting the side wall power supply structure, and the microwaves transmitted through the waveguide are irradiated through the side wall of the heating chamber into the heating chamber. Uneven heating of the object to be heated that may occur at this time may be prevented by rotating the turntable within the heating chamber.
According to the above-mentioned drawer type cooking device, a slide mechanism for moving the drawer body with respect to the cooking device body can be disposed at a lower portion of the side wall space of the heating chamber.
According to the drawer type cooking device of the present invention arranged as above, the following effects are achieved. At first, the turntable disposed on the drawer body enables food to be heated uniformly. Further, since the arrangement adopts a side wall power supply structure in which the waveguide is disposed on the side wall space at the outer side portion of the heating chamber, there is no need to arrange the waveguide on the ceiling, and the ceiling height of the heating chamber can be increased while suppressing the increase of height of the cooking device body.
Moreover, since a movement mechanism for moving the drawer body with respect to the cooking device body is arranged at the lower portion of the side wall space of the heating chamber, a space for arranging the side wall power supply structure is secured in the side wall space, and when the drawer body is drawn out, the movement mechanism is positioned at the lower side of the drawer body so as not to interfere with the operation to take the object in and out of the drawer body, according to which the taking in and out of the object is facilitated. Further, by arranging the operation panel on the upper portion of the door, the thickness of the ceiling can be reduced compared to the case where the operation panel is arranged on the front side of the ceiling, and therefore, the height of the heating chamber can be increased.
The conventionally prevailing drawer type microwave oven is a “single function” type device in which the cooking operation is restricted to the microwave heating operation. On the other hand, a drawer type electrothermal or photothermal cooking device or a drawer type warmer device having a heat-retaining function did not have a microwave heating function. It seems that there has not been any proposal of a drawer type cooking device with a composite function having both the microwave heating function and a different heating function.
However, there are demands from users for a drawer type cooking device having both the microwave heating function and another heating function. The expected use of the additional heating function of such drawer type cooking device is supplemental, such as during a party or the like where a large number of people are to be treated, and the individually disposed electrothermal cooking device is already being used, electrothermal cooking of another food can be performed in parallel using the drawer type cooking device.
The single-function microwave oven has superior energy-saving performance since the cooking operation is completed in a short time compared to hot-air cooking devices and radiant heat cooking devices, but the microwave oven has a short operation time as a cooking device. This is one of the reasons why users feel that single-function microwave ovens have a low level of contribution in the overall heating operation performed in the kitchen. Based on such recognition of the level of contribution of the microwave ovens, consumers desire multiple functions to be adopted in microwave ovens, and responding to such demands has been a challenge for the prior art microwave ovens.
According to the prior-art microwave ovens placed on a counter top, such desires of consumers, especially the desire of consumers to perform baking operation in microwave ovens, has caused the development of microwave ovens having a composite heating function, and consumers are now similarly expecting the drawer type cooking device to have multiple functions.
The object of the present invention is to provide a multi-function drawer type cooking device having a composite cooking function for performing a cooking function corresponding to a wide range of menus by adopting a high-speed hot air heating function to the drawer type microwave oven, which had not been possible according to the prior art drawer type microwave oven.
In order to solve the problems of the prior art, the present invention further provides a drawer type cooking device comprising a cooking device body including a heating chamber, a drawer body having a door for opening and closing an opening of the heating chamber and movably disposed within the cooking device body so as to be drawn out of the interior of the heating chamber of the cooking device body, and a movement mechanism disposed outside the heating chamber and supporting the door on the heating chamber outside the heating chamber so as to move the drawer body within the cooking device body, wherein the drawer type cooking device has both a microwave heating function and a high-speed hot air heating function as the heating functions for heating an object within the heating chamber.
According to this aspect of the invention, the drawer type cooking device has a high-speed hot air heating function in addition to the microwave heating function, so that a variety of cooking methods can be realized via a single cooking device.
The present invention further provides a drawer type cooking device as described above, wherein a turntable for loading the object to be heated is disposed on a bottom portion of the drawer body; the microwave heating function is a function for irradiating microwaves from a side wall of the heating chamber to the object to be heated placed on the turntable; and the high-speed hot air heating function is a function for blowing out hot air at high speed from a ceiling of the heating chamber toward the object to be heated loaded on the turntable, and for blowing out hot air having lower speed compared to the hot air from the ceiling toward the object to be heated loaded on the table.
According to the high-speed hot air heating function, hot air is blown at high speed from the ceiling of the heating chamber toward the upper surface of the object to be heated placed on the turntable, according to which the upper surface of the object to be heated is mainly heated at high speed, but the side surfaces and the lower surface of the object to be heated are not sufficiently heated since the speed of hot air supplied from the ceiling is slowed down and the air passes these areas without performing thermal shock heating. Therefore, patent document 4 (publication of Japanese patent No. 3939232) adopts an arrangement in which hot air supplied through the side wall is blown toward the side surfaces and the lower surface of the object to be heated to compensate for the lack of heating, thereby aiming to achieve uniform heating. As described, a uniform heating mechanism adopting a turntable is necessary to uniformize the partial auxiliary heating using the hot air supplied through the side wall.
The uniform heating mechanism adopting the turntable is also effective for the microwave heating function.
According to the above-mentioned drawer type cooking device, a heat insulating material can be disposed on left and right side walls of the heating chamber and a ceiling of the heating chamber. By disposing heat insulating material on the left and right side walls and the ceiling of the heating chamber, it is possible to ensure the heat insulating effect with respect to the hot air flowing through the outside space of the side wall and the ceiling.
According to the above-mentioned drawer type cooking device, a waveguide for guiding the microwaves generated via a microwave generating device into the heating chamber is disposed on an outside space of the side wall of the heating chamber; and an upper duct for guiding the flow of the hot air heated via a heater is disposed on an outside space of the ceiling of the heating chamber. By disposing the waveguide for guiding the microwaves and the upper duct for guiding the flow of the hot air along the outside space of the side wall or the ceiling of the heating chamber, it becomes possible to prevent the increase of size of the whole body of the drawer type cooking device.
According to the above-mentioned drawer type cooking device, a fan unit composed of a fan and a fan casing storing the fan can be disposed on an outside space on a depth wall of the heating chamber, wherein an upper duct extending to the outside space of the ceiling of the heating chamber and a side wall duct extending to the outside space of the side wall of the heating chamber are connected to the fan casing of the fan unit. By disposing the fan unit on an outside space on a depth wall of the heating chamber and connecting the upper duct and the side wall duct to the fan casing, it becomes possible to send the hot air from the fan unit disposed on the outside space on the depth wall of the heating chamber through the upper duct and/or the side wall duct into the heating chamber, so that the system for supplying hot air into the heating chamber can be simplified.
According to the above-mentioned drawer type cooking device, the upper duct is a duct having a thin rectangular cross-section extending from an upper side air outlet of the fan casing and disposed in a bent manner along the depth wall and the ceiling toward the front side of the heating chamber, and the hot air flowing through the upper duct is blown out through an upper air supply outlet formed centrally around a center area of the ceiling of the heating chamber downward toward the turntable. In other words, since the upper duct is formed as a duct having a thin rectangular cross-section extending from the upper side air outlet of the fan casing in a bent manner along the depth wall and the ceiling, the upper duct having a thin rectangular cross-section arranged along the heating chamber takes up little space. Further, the hot air supplied through the upper duct is discharged through the upper side air outlet formed centrally around the center area of the ceiling of the heating chamber downward toward the object to be heated loaded on the turntable, according to which the object can be cooked via a thermal shock method.
According to the above-mentioned drawer type cooking device, the side wall duct is a duct having a thin rectangular cross-section extending from a side air outlet of the fan casing and disposed in a bent manner along the depth wall and one of the side walls of the heating chamber toward the front side of the heating chamber, and the hot air flowing through the side wall duct can be blown out through a side wall air supply outlet formed centrally around a center area of the one of the side walls of the heating chamber laterally toward an upper area of the turntable. In other words, since the side wall duct is formed as a duct having a thin rectangular cross-section extending from the side air outlet of the fan casing in a bent manner along the depth wall and one of the side walls of the heating chamber, the side wall duct having a thin rectangular cross-section arranged along the heating chamber takes up little space. Further, the hot air supplied through the side wall duct is discharged through the side wall air supply outlet formed centrally around the center area of the side wall of the heating chamber laterally toward the object to be heated loaded on the turntable, according to which the side surfaces of the object to be heated can be cooked via a thermal shock method.
According to the drawer type cooking device of the present invention, an opening connected to an air intake duct of the fan can be disposed at a depth portion of the other side wall of the heating chamber. The hot air blown into the heating chamber heats the object to be heated, and returns from the opening formed at the depth portion of the other side wall of the heating chamber via the intake duct to the fan. The fan can further send out the hot air returned via the intake duct, reheat the same and blow the same via the upper duct and/or the side wall duct into the heating chamber.
The prior art drawer type microwave ovens have disposed on the rear wall portion of the main body of the microwave oven electric components composed of a power supply unit and the like including a magnetron, a high pressure transformer for supplying power to the magnetron, and a high pressure capacitor, and an air blower for blowing air to the electric components for cooling the same, and sending a portion of the air having cooled the electric components into the heating chamber. According to the drawer type cooking device of the present invention, a fan unit composed of a fan and a fan casing storing the fan is disposed on an outside space on a depth wall of the heating chamber, so that the electric components and the air blower are disposed on the side wall, especially on the side wall different from the side wall having the side wall duct disposed thereon.
According to the above-mentioned drawer type cooking device, the drawer body can be supported via the door by the cooking device body outside the heating chamber, and the movement mechanism can be supported on the bottom wall of the heating chamber. Since the drawer body is supported via the movement mechanism by the bottom wall of the heating chamber, it is no longer necessary to use the space on the outer side of the side wall of the heating chamber for disposing the movement mechanism, and this outer side wall space can be used for disposing the side wall duct.
The prior art drawer type microwave ovens have disposed on the rear wall portion of the main body of the microwave oven electric components composed of a power supply unit and the like including a magnetron, a high pressure transformer for supplying power to the magnetron, and a high pressure capacitor, and an air blower for sending a portion of the air having cooled the electric components into the heating chamber. According to the drawer type cooking device of the present invention, a fan unit composed of a fan and a fan casing storing the fan is disposed on an outside space on a depth wall of the heating chamber, so that the electric components and the air blower are disposed on the side wall capable of ensuring space, especially on the side wall different from the side wall having the side wall duct disposed thereon.
The above-mentioned drawer type cooking device according to the present invention has a high-speed hot air heating function in addition to a microwave oven function for microwave heating in a drawer type cooking device, so that a drawer type cooking device capable of performing composite heating operations combining both cooking methods can be provided.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an external perspective view showing a drawer type microwave oven as the drawer type cooking device according to the present invention, wherein the drawer body is drawn out;
FIG. 2 is a perspective view showing the drawer type heating cooker, wherein the drawer body is at a stored state;
FIG. 3 is a schematic side view of the drawer type cooking device according to the present invention, wherein the drawer body is at a drawn out state;
FIG. 4 is a schematic side view of the drawer type cooking device shown in FIG. 3 , wherein the drawer body is stored inside the cooking device body;
FIG. 5 is a cross-sectional side view of the drawer type cooking device according to the present invention;
FIG. 6A is a cross-sectional side view of the drawer type cooking device shown in FIG. 5 , wherein the drawer body is drawn out;
FIG. 6B is a cross-sectional planar view of the drawer type cooking device shown in FIG. 5 , wherein the drawer body is drawn out;
FIG. 7A is a cross-sectional side view of the drawer type cooking device shown in FIG. 5 , wherein the drawer body is stored;
FIG. 7B is a cross-sectional planar view of the drawer type cooking device shown in FIG. 5 , wherein the drawer body is stored;
FIG. 8 is a bottom view of the drawer type cooking device shown in FIG. 5 including a turntable drive mechanism;
FIG. 9 is a perspective view of the drawer type cooking device shown in FIG. 5 , wherein the drawer body is drawn out of the cooking device body;
FIG. 10 is a perspective view of the drawer type cooking device shown in FIG. 6 , wherein the drawer body is pushed into the cooking device body;
FIG. 11 is a bottom view of the drawer type cooking device shown in FIG. 8 , showing a state where a drive gear of the cooking device is engaged with an internally-toothed circular arc gear of a sector gear and then rotated;
FIG. 12 is a bottom view showing another rotation state of the drawer type cooking device illustrated in FIG. 11 ;
FIG. 13 is a schematic side view of the drawer type cooking device according to the present invention, wherein the drawer body is drawn out;
FIG. 14 is a schematic side view of the drawer type cooking device according to FIG. 13 , wherein the drawer body is stored in the cooking device body;
FIG. 15 is an explanatory view illustrating the operation principle of a well-known hot-air cooking operation;
FIG. 16 is an explanatory view illustrating the operation principle of the hot-air cooking operation according to the drawer type cooking device of the present invention; and
FIG. 17 is a perspective view showing one example of a cabinet structure to which the cooking device is built in.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, the preferred embodiments of a drawer type cooking device according to the present invention will be described with reference to the drawings. FIG. 1 is an external perspective view showing the drawer type cooking device according to the present invention as a drawer type microwave oven, wherein the drawer body is shown in the drawn out state. FIG. 2 is a perspective view of the drawer type cooking device according to claim 1 , wherein the drawer body is stored.
As illustrated in FIGS. 1 and 2 , the drawer type cooking device 1 comprises a cooking device body 2 having in the interior thereof a heating chamber 3 into which microwaves are irradiated, and a drawer body 4 capable of being drawn out to the exterior of the cooking device body 2 (the drawn out state being illustrated in FIG. 1 ) from a stored state within the heating chamber 3 (the state shown in FIG. 2 ). The drawer body 4 has a door 5 disposed at a front end portion thereof, wherein the door shuts an opening portion 6 of the heating chamber 3 when the drawer body 4 is stored in the cooking device body 2 .
An operation panel 5 b is disposed together with a handle 5 a at an upper portion of the door 5 disposed on the front side of the drawer body 4 . Since the operation panel 5 b is disposed at the upper portion of the door 5 , there is no need to dispose the operation panel on a front side of a ceiling portion 11 of the cooking device body 2 as according to the prior art, the thickness of the ceiling portion 11 can be suppressed to realize a thinner structure, and the height of the cooking device body 2 can therefore by suppressed. Further, a window 5 c allowing users to look into the heating chamber 3 while preventing microwave transmission is formed on the front side of the door 5 . A slide mechanism 18 capable of allowing the drawer body 4 to be drawn out of or stored into the cooking device body 2 is disposed between the lower side portion of the door 5 constituting the structure of the drawer body 4 and a lower portion of the side wall space of the cooking device body 2 .
FIG. 1 shows a state where the movable rail 18 b constituting the slide mechanism 18 is attached to a lower side portion of the door 5 . The slide mechanism 18 is disposed on the outer side of the heating chamber 3 so as not to be influenced by microwaves or food residue and the like of the heating cooker, and the mechanism can comprise a movable rail 18 b attached to both side portions of the door 5 and a fixed rail 18 a attached to the cooking device body 2 and slidably attached to the movable rail. In the present embodiment, the movable rail 18 b is a transversely disposed long rail, which is slidably supported with respect to the fixed rail 18 a in the cooking device body 2 (refer to FIGS. 3 and 4 ). The fixed rail 18 a is driven to be drawn out of or stored into the cooking device body 2 via the output of a motor as drive source disposed within the cooking device body 2 . By this movement of the movable rail 18 b , the drawer body 4 can be drawn out of or stored into the heating chamber 3 of the cooking device body 2 via the door 5 . The slide mechanism 18 equipped with a drive mechanism such as a motor and a transmission mechanism for transmitting the output thereof enables to automatically open and close the drawer body 4 .
By adopting the above-described arrangement, according to the drawer type cooking device disclosed in patent document 1 (Japanese patent application laid-open publication No. 2005-221081: Publication of Japanese patent No. 4027325) the fixed rail 18 a is disposed substantially at the center of height of the outer side wall of the heating chamber, but the fixed rail is moved along an extended line of a lower portion of the outer side wall of the heating chamber, so that the space having been occupied by the fixed rail 18 a and the movable rail 18 b according to the prior art can be used to arrange a side wall power supply mechanism.
In FIG. 1 , the drawer body 4 is composed of both side walls 15 and 15 having a low height, a rear wall 16 and a bottom wall 17 , but only small portions thereof are illustrated. The front end portions of the side walls 15 and 15 and the bottom wall 17 are attached to the door 5 . The upper area of the drawer body 4 is opened, and when the drawer body 4 is drawn out of the cooking device body 2 , an object to be cooked such as a tray T and food F placed thereon to be heated can be put into or taken out of the drawer body 4 . Since the height of the side wall 15 is sufficiently low compared to the height of the heating chamber 3 , the object to be cooked such as food can also be easily put into or taken out of the drawer body 4 from the sides.
FIGS. 3 and 4 are schematic side views of the drawer type cooking device according to the present invention, wherein FIG. 3 is a view showing the state where the drawer body is drawn out, and FIG. 4 is a view showing the state where the drawer body is stored in the cooking device body. The elements also illustrated in FIGS. 1 and 2 are provided with the same reference numbers, and the descriptions thereof are omitted. FIGS. 3 and 4 show side views for better understanding of the relative arrangements of elements viewed from the side for describing the side wall power supply structure.
On the rear wall portion 10 of the cooking device body 2 are disposed a magnetron 7 for generating microwaves, a high pressure transformer 9 (not shown in FIGS. 3 and 4 ) for supplying power to the magnetron 7 , electric components such as a power supply unit including a high pressure capacitor, and an air blower for blowing air toward the electric components for cooling the same and for sending a portion of the air having cooled the electric components into the heating chamber 3 .
A side wall power supply structure 51 composed of a waveguide 8 for conducting the microwaves having been generated by the magnetron 7 from the rear wall portion 10 into the heating chamber 3 is disposed on a side wall space 50 ( FIG. 1 ) formed within the cooking device body 2 on the outer side portion of the heating chamber 3 . The magnetron 7 is stored in the rear wall portion 10 , but an antenna for outputting the generated microwaves is inserted through an opening formed on a depth portion of the waveguide 8 into the waveguide 8 , so that the microwaves generated by the magnetron 7 can be propagated in the waveguide. The microwaves thus introduced through the waveguide 8 are irradiated through the side wall 13 of the heating chamber 3 (refer to FIG. 5 ) into the heating chamber 3 .
In FIGS. 3 and 4 , a turntable 20 is rotatably disposed on a bottom wall 17 of the drawer body 4 , and a drive mechanism 40 (which will be described in detail later) for rotating the turntable 20 is disposed in a space 19 formed between an upper surface of the bottom wall portion 12 of the cooking device body 2 and the bottom wall 17 of the drawer body 4 at the stored state. A fixed rail 18 a of the slide mechanism 18 is fixed to the cooking device body 2 at the lower portion of the side wall space 50 , which supports a movable rail 18 b attached to the door 5 in a slidable manner. The weight of the drawer body 4 and the object to be cooked can be supported by the heating chamber 3 via a roller or other means (not shown) at the rear portion, and can be supported by the cooking device body 2 via the movable rail 18 b through the door 5 at the front portion. Further, a wire arrangement (not shown) for supplying power, sending and receiving signals and the like for the operation panel 5 b is arranged along the fixed rail 18 a and the movable rail 18 b.
Now, we will describe the turntable driving mechanism adopted in the drawer type cooking device of the present invention. FIG. 5 is a cross-sectional side view of the drawer type cooking device, FIG. 6A is a cross-sectional side view showing the drawer type cooking device illustrated in FIG. 5 with the drawer body drawn out, FIG. 6B is a cross-sectional planar view showing the drawer type cooking device illustrated in FIG. 5 with the drawer body drawn out, FIG. 7A is a cross-sectional side view showing the drawer type cooking device illustrated in FIG. 5 with the drawer body stored, FIG. 7B is a cross-sectional planar view showing the drawer type cooking device illustrated in FIG. 5 with the drawer body stored, and FIG. 8 is a bottom view of the drawer type cooking device including a turntable drive mechanism.
The cooking device body 2 has a magnetron 7 for generating microwaves disposed at the rear wall portion 10 thereof, and a waveguide 8 disposed on a ceiling portion 11 for introducing the microwaves generated by the magnetron 7 into the heating chamber 3 . Further, an air blower for sending air to the power supply system or the heating chamber 3 is disposed on the rear wall portion 10 of the cooking device body 2 . Moreover, the drive mechanism 40 of the turntable according to the present invention is disposed on the bottom wall portion 12 of the cooking device body 2 .
A space 19 for arranging the turntable drive mechanism 40 according to the present invention described later is formed between the upper surface of the bottom wall portion 12 of the cooking device body 2 and the bottom wall 17 of the drawer body 4 .
In order for the drawer body 4 to be able to be drawn out with respect to the cooking device body 2 , a slide mechanism (not shown) is disposed between the cooking device body 2 and the drawer body 4 .
A turntable 20 capable of rotating arbitrarily around a center axis 21 is mounted at the upper center portion of the bottom wall 17 of the drawer body 4 . An object to be cooked (a tray T and food F to be heated) is placed on the rotation table 20 . A rotary shaft 21 fixed to the turntable 20 at an upper end portion 22 is disposed on the lower side of the turntable 20 , and the rotary shaft 21 is extended below the drawer body 4 through the bottom wall 17 of the drawer body 4 . At the lower area of the bottom wall 17 , a drive gear 24 as turntable transmission unit is attached to the lower end 23 of the rotary shaft 21 for rotating and driving the turntable 20 (which will be described in detail later). Further, a disk 25 is fixed to the rotary shaft 21 at the center area thereof, and support shafts 26 , 26 and 26 extending at angular intervals (in the example, in three directions at 120-degree intervals) are attached to the disk 25 . Each shaft 26 has a roller 27 rotatably disposed thereto, wherein the roller 27 contacts the turntable 20 at the upper side thereof and contacts the bottom wall 17 at the lower side thereof, and rolls on the bottom wall while supporting the weight of the turntable 20 and the object to be cooked.
A motor 30 as an external drive source for driving the turntable 20 is arranged at one corner within the bottom wall portion 12 of the cooking device body 2 . The output shaft 31 of the motor 30 is extended upward through the bottom panel of the bottom wall portion 12 via an electric wave leak structure and protrudes into the heating chamber 3 . Thus, the motor 30 is placed outside the heating chamber 3 , so that it is not exposed to microwaves irradiated into the heating chamber 3 . An output gear 32 as rotation motor transmission unit is attached to the upper end of the output shaft 31 . Further, a sector gear 33 having a substantially fan shape is pivotally supported on a pivot axis 34 on the upper side of the bottom wall portion 12 . The rotation shaft 21 of the turntable 20 occupies the center position between the pivot axis 34 of the sector gear 33 and the output shaft 31 of the motor 30 when the drawer body 4 is at the stored state.
The sector gear 33 has on the outer circumference side of the fan-shaped body a circular arc-shaped externally toothed gear portion 35 constantly engaged with the output gear 32 and forming a first engagement portion, and has on the inner circumference side of the fan-shaped body having a concentric shape with the outer circumference of the fan shape a circular arc-shaped internally-toothed gear portion 36 engaged with the drive gear 24 and forming a second engagement portion. In order to enable the internally-toothed gear portion 36 to be removed and attached along the horizontal direction, the portion 36 is somewhat lifted up in an offset manner in the axial direction from the fan-shaped body of the sector gear 33 . The pivot axis 34 is placed at a position close to the opening 56 of the heating chamber 3 so as not to interfere with the drive gear 24 passing by when the drawer body 4 is moved in and out. The output gear 32 , the sector gear 33 and the drive gear 24 constitute a power transmission mechanism 40 for transmitting the output rotation of the motor 20 to the turntable 20 .
The internally-toothed gear portion 36 forming the second engagement portion has a pitch radius having a radius of curvature sufficiently greater than the drive gear 24 of the rotary portion, which is opened toward the direction of movement of the drawer body 4 . When the drawer body 4 is stored in the cooking device body 2 , the drive gear 24 is simply moved in the horizontal direction so as to engage with the internal tooth of the internally-toothed gear portion 36 via a moderate accuracy, and when the drawer body 4 is opened, the drive gear 24 simply moves in the horizontal direction and is disengaged smoothly from the internally-toothed gear portion 36 .
As described, the turntable 20 is rotatably disposed on the bottom wall 17 of the drawer body 4 , and the rotary shaft 21 of the turntable 20 is protruded downward through the bottom wall 17 of the drawer body 4 . A driving motor 30 is disposed on the outer side of the bottom wall portion 12 of the heating chamber 3 , and the output shaft 31 of the motor 30 is protruded upward through the bottom wall portion 12 of the heating chamber 3 via the electric wave leak structure. The lower end 23 of the rotary shaft 21 of the turntable 20 and the output shaft 31 of the motor 20 are horizontally spaced apart and disposed in the space 19 formed between the bottom wall 17 of the drawer body 4 of the drawer type cooking device 1 and the upper surface of the bottom wall portion 12 of the heating chamber 3 , and the drive gear 24 and the output gear 32 are respectively disposed in a horizontally offset manner.
FIG. 9 is a perspective view showing the state where the drawer body 4 is drawn out of the cooking device body 2 , and FIG. 10 is a perspective view showing the state where the drawer body 4 is pressed into the cooking device body 2 . When the drawer body 4 is pushed into the cooking device body 2 , the drive gear 24 appearing outward from the bottom wall 17 of the drawer body 4 is moved in the space 19 above the bottom wall portion 12 . When the drawer body 4 is completely pushed into the cooking device body 2 , the drive gear 24 is engaged with the internally-toothed gear portion 36 of the sector gear 33 .
FIGS. 11 and 12 illustrate how the drive gear 24 being engaged with the internally-toothed gear portion 36 of the sector gear 33 is rotated. FIG. 11 shows a state where the sector gear 33 is swung to the farthest position in the counterclockwise direction. FIG. 12 shows a state where the sector gear is swung to the farthest position in the counterclockwise direction. When the motor 30 is driven and the output shaft 31 together with the output gear 32 attached thereto rotates, the sector gear 33 pivots about the pivot axis 34 , and the drive gear 24 engaged with the internally-toothed gear portion 36 is driven to rotate. By automatically reversing the direction of rotation of the motor 30 in response to the position of the sector gear 33 , the sector gear 33 is inverted and pivots repeatedly within the pivoting range. The pivoting range of the sector gear 33 corresponds to a single rotation of the drive gear 24 .
According to the arrangement of the present embodiment, since a turntable 20 is disposed in the drawer body 4 , the floor surface of the drawer body 4 is raised and the ceiling height of the heating chamber 3 is relatively lowered, but since the uniform heating mechanism including the turntable 20 is provided, the rotation antenna having been mounted on the ceiling surface can be eliminated and the antenna-rotating motor mounted on the upper portion of the waveguide 8 can be eliminated. Thus, the lowering of ceiling height due to the height of the turntable 20 can be substantially compensated, enabling use of food or dishes having substantially the same height as those used in the prior art drawer type cooking device.
After the drawer body 4 is pressed and stored in the cooking device body 2 and preparation for cooking has been completed, the motor 30 is driven. By reversing the rotation of the motor 30 output per a predetermined number of rotations, the output gear 32 can pivot the sector gear 33 engaged therewith around the pivot axis 34 within a predetermined pivot angle. By reversing the rotation of the rotary shaft 21 of the drive gear 24 , the rotation of the turntable 20 is inverted repeatedly at predetermined angles. The turntable 20 does not rotate continuously but pivots back and forth within a fixed rotation angle, but since the loaded object to be cooked passes substantially all the distribution area of microwaves distributed in a non-uniform manner, the dispersion of microwaves is equalized, and uniform heating substantially equal to the continuously rotated turntable is enabled.
As described, since uniform heating is enabled by the pivot-rotation of the turntable, the power transmission between the output gear 32 of the motor 30 positioned at one corner of the drawer body and the drive gear 24 positioned near the center area of the drawer body can be performed via the sector gear 33 instead of a circular gear, and the sector gear 33 moves in pivoting motion around the pivot axis 34 disposed at the corner opposite to the motor 30 of the drawer body.
Furthermore, the engagement between the drive gear 24 and the sector gear 33 is performed by the engagement of the circular arc-shaped internally-toothed gear portion 36 and the drive gear 24 , but since the circular arc-shaped externally-toothed gear portion 35 has a radius substantially equal to the turntable and realizes a gear reduction ratio of the level substantially rotating the turntable for a single rotation by the pivoting movement of the sector gear 33 within the mechanically pivotable angular range of the sector gear, so that the drive gear 24 having a small outer shape is engaged with the arc-shaped internally-toothed gear portion 36 having a small curvature. Therefore, even if the position of the drive gear 24 is somewhat dispersed in the width direction of the cooking device body, gear engagement is facilitated during the engagement and disengagement operation.
If the motor 30 is designed so that its rotational output is continuous rotation but the mechanical arrangement thereof enables the rotation to be inverted within a fixed rotational angle, the motor having the required drive performance can be achieved inexpensively.
In order for the rotation of the output shaft 31 of the motor 30 to be inverted per a predetermined number of rotations, the motor 30 can utilize a servomotor in which a rotary encoder is disposed on the output shaft 31 . The servomotor is capable of high level control, and is capable of obtaining a time series data of rotation angles. In an arrangement using the servomotor, it is possible to compute the rotational moment of the turntable 20 having food loaded thereon without performing feedback control by processing the rotational angle data when the motor is driven via a fixed rotational torque without performing feedback control. Since such rotational moment is strongly correlated with the mass of the food, the food mass can be estimated and used for setting up the heating time for performing automatic cooking. Automatic cooking is preferable, since in addition to the finish detection using a moisture sensor and the like, it is capable of preventing lack of heating or overheating of extremely large amounts or extremely small amounts of food.
When the drawer body 4 is stored, the rotation angle of the turntable 20 is uncertain, and if the engagement portion utilizes gears, it is possible that the engagement of the gears is incomplete. In that case, the engagement of the gears can be adjusted by slightly moving the power transmission mechanism 40 while applying horizontal movement force. Therefore, it is preferable that the power transmission mechanism 40 is controlled so that it is always slightly moved when the drawer body 4 is stored.
According to the above-mentioned power transmission mechanism 40 , it is possible to replace the gears of the first and second engagement portions including the output gear 32 , the sector gear 33 and the drive gear 24 with plastic toothed belts attached to the inner circumference sides of circular elastic bodies. The toothed belt arrangement is more preferable since less incomplete engagement occurs.
According to the above-mentioned power transmission mechanism 40 , it is even more preferable to realize the first and second engagement portions via friction engagement of friction wheels with circular surfaces or circular-arc surfaces having a high friction coefficient instead of via the engagement of gears including the output gear 32 , the sector gear 33 and the drive gear 24 , since the problem of mismatch of gear engagement does not occur.
Further, except for the motor disposed outside the heating chamber 3 , the power transmission mechanism 40 according to the present embodiment is disposed within the heating chamber 3 of the cooking device, above the drawer 4 or in the space 19 between the drawer body 4 and the heating chamber 3 . Therefore, the power transmission mechanism 40 is exposed to electromagnetic induction via microwaves during cooking operation, but problems such as discharge or overheating will not occur to the structure if appropriate materials such as heat-resistant plastics, ceramics or heat-resistant glass having low dielectric loss are selected.
By adopting a uniform heating mechanism using a turntable 20 according to the present invention, the prior art rotation antenna disposed within a waveguide arranged on the ceiling becomes unnecessary. In the prior arrangement using the rotary antenna, the rotation state could not be visually confirmed, so the rotation state of the rotary antenna had to be confirmed via an electric or an optical rotation detecting means, but the present invention is preferable since such confirmation means becomes unnecessary. Further, since the rotation antenna becomes unnecessary, the antenna rotation motor disposed on the upper side of the ceiling waveguide no longer becomes necessary. Therefore, the ceiling surface of the heating chamber can be raised by approximately 20 mm. Thus, since the ceiling surface of the heating chamber 3 can be raised by approximately 60 mm in the end by taking measures such as moving the side wall power supply mechanism and the waveguide, moving the operation panel to the door, and arranging the side wall slide mechanism at a lower position, the ceiling height which was approximately 180 mm according to the prior art can be raised to 240 mm. Therefore, objects to be heated (such as food and drinks) can be heated in containers having a high height.
Since the pitch circle radius of the sector gear 33 of the power transmission mechanism 40 of the turntable 20 is large, the curvature of the pitch circle is small, and together with the fact that the sector gear 33 is socketed with respect to the horizontal moving direction of the drawer body 4 , the positional relationship between the drawer body 4 and the heating chamber 3 is tolerant to the displacement in the width direction, and the engagement or disengagement of the gear of the turntable and the sector gear 33 is facilitated.
The above arrangement is preferable, since even when the user applies a lateral operation force to the drawer body when opening the door by holding the door handle and the drawer body is moved in a slanted direction, the misalignment of the engagement position of the gear of the turntable with respect to the recessed portion of the fan-shaped gear does not affect the effective engagement of the gears.
According to the present embodiment, the power transmission mechanism 40 is composed of independent components not related to the turning tray T or the turntable 20 , not like the invention of U.S. Pat. No. 5,796,802 where a transmission unit such as a circumference toothed portion is disposed on the outer circumference of the turning tray, the present invention can lower the manufacturing cost while maintaining the dimensional accuracy of the sector gear 33 and the like. Since the only opening added to the drawer body 4 is the through portion of the rotary shaft 21 of the turntable 20 disposed at the center of the bottom wall 17 of the drawer body 4 , and it is easy to realize a seal structure capable of preventing microwaves or water from passing such through portions at a low cost. Furthermore, since the power transmission mechanism 40 is stored below the bottom wall 17 of the drawer body 4 and the engagement portion of the output shaft 31 of the motor 30 and the sector gear 33 is disposed at the corner portion of the drawer body 4 , it is no longer necessary to widen the space between the rear wall of the drawer body 4 and the rear wall of the heating chamber, so that a detachable tray T can be adopted as the drawer body 4 without reducing the depth of the drawer body 4 .
FIGS. 13 and 14 are schematic side views of the drawer-type cooking device according to the present invention, wherein FIG. 13 shows a state where the drawer body is drawn out, and FIG. 14 shows a state where the drawer body is stored in the cooking device body. The components equivalent to those illustrated in FIG. 1 or 2 are denoted with the same reference numbers, and the detailed descriptions thereof are omitted. FIGS. 13 and 14 show side views for better understanding of the relative arrangements of elements for illustrating the side wall power supply structure.
In a side wall space 50 ( FIG. 1 ) formed at the outer side portion of the heating chamber 3 and within the cooking device body 2 are disposed electric components composed of power supply units including a magnetron 7 , a high pressure transformer 9 a for supplying power to the magnetron 7 and a high pressure capacitor 9 b , and a cooling fan 9 c for blowing air to and cooling the electric components and further sending a portion of the air having cooled the electric components into the heating chamber 3 .
Further, a side wall power supply structure 51 composed of a waveguide 8 for introducing the microwaves having been generated by the magnetron 7 into the heating chamber 3 is disposed in the side wall space 50 . Since an antenna for outputting the generated microwaves is inserted through an opening formed at a depth portion of the waveguide 8 into the waveguide 8 , the microwaves generated by the magnetron 7 can be propagated in the waveguide 8 . The microwaves thus introduced through the waveguide 8 are irradiated through the side wall 13 (refer to FIG. 5 ) of the heating chamber 3 into the heating chamber 3 .
In FIGS. 13 and 14 , a turntable 20 is rotatably disposed above a bottom wall 17 of the drawer body 4 , and a power transmission mechanism 40 (which will be described in detail later) for rotating the turntable 20 is disposed in a space 19 formed between an upper surface of the bottom wall portion 12 of the cooking device body 2 and the bottom wall 17 of the drawer body 4 at the stored state. The fixed rail 18 a of a slide mechanism 18 is fixed to the cooking device body 2 at the lower portion of the side wall space 50 , which supports a movable rail 18 b mounted on the door 5 in a slidable manner. The weight of the drawer body 4 and the object to be cooked can be supported by the heating chamber 3 via a roller or other means (not shown) at the rear portion, and can be supported by the cooking device body 2 via the movable rail 18 b through the door 5 at the front portion. Further, a wire structure (not shown) for supplying power, sending and receiving signals and the like for the operation panel 5 b is arranged along the fixed rail 18 a and the movable rail 18 b.
Now, with reference to the drawing ( FIG. 15 ), the operation principle of a hot-air heating cooker disclosed in the aforementioned patent document 4 (publication of Japanese Patent No. 3939232) will be described. FIG. 15 is a perspective view showing the outline of a hot-air heating cooker engine unit. As shown in FIG. 15 , the hot-air heating cooker engine unit 100 is composed of a centrifugal fan 101 capable of controlling the directions of rotation and the number of rotations, and air blow ducts 102 and 103 branched into two directions. The air blow fan 101 is a centrifugal fan, which is disposed at a rear wall portion 10 (in the space at the rear side of the wall at the depth of the heating chamber).
According to a first hot-air cooking method, the fan 101 is rotated in a counterclockwise direction (ACW), according to which a large amount of air is supplied to the upper duct 102 and a small amount of air is supplied to the side duct 103 . The fan 101 is driven at high speed rotation so that the air blowing downward from the upper duct 102 is at a high speed of 50 km/h or higher required for impingement cooking. At this time, the speed of the air flow from the side duct 103 is fairly lower than 50 km/h. Therefore, impingement cooking is performed at the portion where the air flow from the upper duct 102 blows, and normal hot air cooking is performed at the portion where the air flow from the side duct 103 blows.
According to the second hot air cooking method, the fan 101 is rotated in the clockwise direction (CW), and as for the air flow ratio of the upper duct 102 and the side duct 103 compared to the first hot air cooking method, more ratio of air is supplied to the side duct 103 and less ratio of air is supplied to the upper duct 102 . The air flow from the upper duct 102 and the side duct 103 is fairly slow with respect to the 50 km/h, and as a whole, hot air cooking close to convection heating is performed. Unlike normal hot air heating cookers, according to the above-mentioned two types of hot air cooking methods, the direction in which hot air is blown from the side duct 103 toward the food is biased, so that food must be rotated via a uniform heating mechanism such as a turntable.
Next, with reference to FIG. 16 , the operation principle of hot air cooking according to the drawer-type cooking device of the present invention will be described. The drawer type cooking device is composed of the drawer type cooking device illustrated in FIG. 15 plus additional structures such as the turntable 20 , the upper heater 131 and the side heater 132 . Therefore, the drawer type cooking device of the present invention reflects the basic heating/cooking principles of the impingement cooking based on the direction of rotation of the fan of the impingement cooking engine portion 100 and the principles of cooking close to convection heating.
The heating chamber 3 excluding the front side thereof is surrounded by five walls. That is, the heating chamber 3 is surrounded by a heating chamber top wall surface 111 constituting the ceiling wall of the heating chamber 3 , a left wall surface 112 and a right wall surface 113 of the heating chamber disposed upright at left and right sides, a heating chamber bottom wall surface 114 supporting a turntable 20 in a rotatable manner, and a depth wall surface 115 of the heating chamber disposed upright at the depth of the heating chamber 3 .
The hot air heating engine portion 100 shown in the former drawing is attached to the outer wall of the heating chamber 3 having the turntable 20 . The upper duct 102 is bent by 90 degrees so that it extends frontward in contact with the ceiling wall surface, and an opening 121 is formed on the ceiling wall surface 111 of the heating chamber 111 around the center portion of the ceiling wall surface of the heating chamber in correspondence with the upper wall blowout openings 104 of the upper duct 102 , through which hot air is blown downward through the opening 121 . The side duct 103 is bent by 90 degrees so as to extend frontward in contact with the left side wall surface, and a rectangular opening 122 is disposed substantially at the center of the side wall of the heating chamber in correspondence with the side wall blowout opening 105 formed at the leading end portion of the side wall duct 103 on the left side wall surface of the heating chamber, through which hot air is blown rightward through the opening 122 . The casing of the fan 101 has an upper duct 102 connected in the upward direction, and a side duct 103 having a thin rectangular cross-sectional shape connected in the left direction.
An upper heater 131 and a side heater 132 composed of honeycomb heaters or sheathed heaters are provided as heaters to the inner side of the upper duct 102 and the side duct 103 . On the other hand, an opening 123 is formed at the lower right corner of the depth wall 115 of the heating chamber, and an air intake duct 107 extending to an intake port 106 of the fan 101 is disposed to the opening 123 . In order to improve the circulation of hot air within the heating chamber 3 , the opening 123 is disposed at a point close to the antipodal point of the side wall blowout port 105 having the turntable 20 disposed therebetween.
When hot air cooking is performed, the hot air blowing out through the upper blowout ports 104 and the side wall blowout port 105 is converged and reaches the air intake port 106 of the fan 101 through the intake opening 123 , constituting a circular air flow. If the upper blowout ports 104 are designed so that air is blown out through the whole ceiling wall surface 111 of the heating chamber, since the air flow blowing downward is of high speed, the relatively slow air flow from the side wall blowout pot 105 is blown downward and cannot heat the side walls and the lower portions of the food, according to which uniform heating is obstructed. In order to solve this problem, a portion of the upper blowout ports 104 is closed near the opening 121 so that only the upper blowout ports 104 superposed with the opening 121 allow air to blow downward, so as not to affect the relatively slow air flow blown from the side wall blowout port 105 .
According to the prior art, the microwaves generated via the magnetron is irradiated into the heating chamber via the waveguide disposed on the ceiling structure, and a rotary antenna for agitating the microwaves is disposed within the waveguide, so that it was difficult to adopt the hot air cooking structure using the ceiling structure as duct. However, according to the present invention, a turntable 20 disposed on the bottom wall of the drawer body without using the ceiling structure is disposed as the uniform heating structure while adopting a side wall power supply structure 51 arranging the waveguide 8 in the side wall space 50 of the heating chamber, so that high speed hot air cooking function using a fan 101 and ducts 102 and 103 can be adopted in the cooking device body 2 . According to the present embodiment, the ceiling structure is not used for the uniform heating structure, and the slide mechanism of the drawer body 2 is moved to the lower portion of the cooking device body 2 , while the remaining space composed of the heating chamber ceiling wall surface 111 and left and right side walls of the heating chamber have heat insulating materials attached thereto. According to the present embodiment, the operation panel 5 b is moved to the upper portion of the door 5 , but it can also be disposed at the upper portion of the main body, similar to the prior art drawer type cooking devices.
When the fan 101 is rotated at high speed in the counterclockwise direction, high speed air flow is blown downwards toward the upper surface of the food through the upper blowout ports 104 on the ceiling wall surface 111 of the heating chamber, thereby enabling to cook the food via impingement cooking. At the same time, relatively slow flow of hot air is blown from the side toward the lower portion of the food through the side wall blowout port 105 on the side wall 112 of the heating chamber, by which auxiliary heating compensating for the lack of heating of the lower portion of the food not subjected to impingement cooking is performed. Furthermore, when the fan 101 is rotated at low speed in the clockwise direction, relatively slow flow of hot air is blown toward the food from the ceiling wall surface 111 of the heating chamber and the side wall surface 112 of the heating chamber, according to which cooking close to convection heating is enabled. According to both heating methods, the food is rotated on the turntable 20 during heating, so uniform heating of food becomes possible.
Patent document 4 (Japanese Patent No. 3939232) discloses a high speed hot air heating cooker that the present applicant provided to the market, but since it is designed mainly with the aim to reduce the cooking time of a relatively large amount of meat or the like to a speed comparable to the cooking time of gas heating cookers, the heating cooker is large-sized having a heating chamber ceiling height of 30 cm or higher and an inner volume of over 40 L, with a consumption power as high as 2000 W. Accordingly, the built-in installation of such large-sized high speed hot air heating cooker is not easy since the external dimension thereof is irregular and heat-radiation cooling is difficult. Thus, the heating cooker is normally disposed in an open space on a countertop.
On the other hand, due to the limitation in the space to which the cooking device is to be built in, the drawer type cooking device according to the present invention must perform impingement cooking with reduced consumption power.
According to the drawer type cooking device of the present invention, the heating chamber ceiling height is approximately 20 cm or smaller, and the heating chamber inner volume is small, not greater than approximately 25 L. Therefore, according to the first hot air cooking method mentioned above, even if the wind speed of hot air is equivalent, the heat quantity required for cooking is reduced, by which the cross-sectional area of the air duct can be reduced and the hot air flow quantity can be reduced. Further, since the distance between the hot air blowout ports on the ceiling wall and the food is short, the heating efficiency is high, so that even if the cooking device performs impingement cooking, the overall heating power can be reduced to approximately ½.
According to the second hot air heating method mentioned above, the high speed hot air heating cooker disclosed in patent document 4 (Japanese Patent No. 3939232) assumes placing a loading stage on the turntable and mounting food on two stages for cooking. On the other hand, the drawer type cooking device according to the present invention mounts food only on a single stage on the loading stage placed on the turntable, so as to reduce the heating power to approximately ½.
The present invention realizes reduction of size and heating power, according to which the consumption power of the device becomes equivalent to that during microwave heating, and except for the fact that the time required for heating and cooking is longer compared to microwave heating and cooking, air intake and exhaust including heat radiation of the present device is enabled according to a similar exhaust air cooling structure as that of the prior art drawer type microwave ovens, according to which the built-in installation of a high-speed hot air cooking device, which had been difficult according to the prior art, is enabled for the first time. According to the drawer-type cooking device of the present invention, it is preferable to have a wider side wall space in order to support the air flow duct such as the side wall duct, attach heat insulating material, store electric components, and to ensure air cooling. Therefore, as shown in FIG. 17 , it is assumed that the cabinet structure suitable for built-in installation of the drawer type cooking device is the cabinet structure of the wider type out of the two standard sizes.
The hot air cooking function of the drawer type cooking device according to the present invention has an equivalent consumption power during cooking as the consumption power of the microwave cooking operation, due to the reduction of heating power by the reduced size and reduced heating load of the present device, and when the present device is stored in a space having an outer dimension similar to the prior art drawer type microwave oven, electric components can be cooled and cooking heat can be discharged by the improvement in the design of the air cooling structure and the like. Therefore, the present invention responds to the demands of consumers by providing a high-speed hot air cooking device to be built into a kitchen, which was not possible according to the prior art.
Furthermore, the composite cooking function of the present invention enables the drawer type cooking device to perform the cooking operation that had been conventionally performed by other cooking devices in the kitchen, by which the operation of the various cooking devices can be leveled and the overall time required for cooking can be reduced, and the present invention preferably responds to the demands of consumers in this manner. | The invention provides a drawer type microwave oven having a turntable functioning as a uniform heating mechanism with a visual effect, while maintaining the ceiling height of a heating chamber and having improved usability. A turntable drive mechanism 40 utilizing a thin deceleration mechanism and a pivot mechanism is disposed in a space 19 formed between a bottom wall 17 of the drawer body 4 and a bottom wall 12 of the heating chamber 3 , and a power transmission mechanism is engaged in a detachable manner in conjunction with the movement of the drawer body 4 together with the door. Thus, a drawer type microwave oven capable of performing uniform heating by pivot rotation while maintaining the ceiling height of the heating chamber is realized. | 7 |
TECHNICAL FIELD
The present invention relates to automotive cupholders and particularly to a selectively deployable cupholder which is telescopically nestable and is adaptable for sliding drawer applications.
BACKGROUND OF THE INVENTION
Modern automotive interior design makes great strides to provide convenience for vehicle passengers. One of these conveniences is the cupholder for holding liquid filled beverage containers, with due regard for the inertial forces commonly involved with normal driving.
Numerous cupholder designs have been executed in a variety of automotive applications by a variety of manufacturers. These cupholder designs generally fall within one of two categories: static component cupholders and active component cupholders.
Static component cupholders generally involve molding a “pocket” into an automotive interior component, as for example a floor console, a door panel, etc, with sufficient diametric clearance and depth to accommodate a variety of commonly used beverage containers. While of low cost and durable, this type of cupholder generally does not provide an acceptable tradeoff between packaging space and cupholder functionality. Specifically, packaging space is negatively influenced as the “pocket” wall size dimensions are increased to provide sufficient depth for large beverage containers with high centers of gravity.
Active component cupholders generally involve multiple pieces that are attached by springs, pins, or other linkages which allow the individual components of the design to “nest” within each other, thereby optimizing packaging space. This cupholder design also allows for a wider size range of beverage containers by optimization of the component piece parts and the locational functionality of the springs, pins or other linkages within the design. However, the active component cupholder design is generally more expensive, more complex, more difficult to manufacture, and has poorer durability performance, as compared to static component cupholder designs.
Accordingly, what remains needed in the art is a cupholder design that is the best of the static and active component designs, providing an optimal balance between the imperatives of packaging space, cost, durability, and cupholder functionality for use in an automotive interior application, and further providing very compact storage of multiple, tall, and effective cupholders achieved with a minimal number of movable component parts.
SUMMARY OF THE INVENTION
The present invention is a selectively deployable cupholder that incorporates the best aspects of the static and active component designs, providing an optimal balance between the imperatives of packaging space, cost, durability, and cupholder functionality for use in an automotive interior application, and further providing very compact storage of multiple, tall, and effective cupholders achieved with a single movable component part. In this regard, the present invention, while falling within the active component cupholder category, overcomes the deficiencies associated with other designs in this category by avoiding the use of springs, pins, or other linkages.
The selectively deployable cupholder according to the present invention is composed of a stationary cylindrical (ring shaped) component and a movable cylindrical (ring shaped) component telescopically nested within the stationary cylindrical component. The stationary cylindrical component may be permanently connected, or removably connected, to a surrounding trim component, which may or may not supply the floor of the cupholder. When the movable cylindrical component is in an undeployed state, whereat it is fully nested with respect to the stationary cylindrical component, a low vertical profile is provided, suitable for drawer applications. When the movable cylindrical component is in a deployed state, whereat it is fully telescopically raised relative to the stationary cylindrical component, the cupholder receives beverage containers with a stable support therefor, as is required for use in an automotive driving environment.
The movable cylindrical component is provided with a plurality of bosses emanating from its outer wall surface adjacent the lower end thereof. The stationary cylindrical component has a plurality of tracks formed into an inner wall surface, one for each boss. Each boss is received into its respective track, wherein the tracks guide telescopic movement of the movable cylindrical component with respect to the stationary cylindrical component. An upper detent and a lower detent are provided at each track for defining the upper and lower telescopic limits of travel of the movable cylindrical component with respect to the stationary cylindrical component via the bosses, respectively. In this regard, each detent and its respective boss interact in a resilient manner so as to provide a snapping location of the boss in the detent which is detectable by the user, wherein this feedback provides user awareness of achievement of each limit of telescopic travel.
Accordingly, it is an object of the present invention to provide a cupholder having only a single moving component part which provides the best aspects of both the static component and active component cupholder designs.
It is an additional object of the present invention to provide a cupholder having only a single moving compoinent part which provides the best aspects of both the static component and active component cupholder designs, wherein the cupholder is adapatable for use with a sliding drawer which is slidably stowable.
These and additional objects, features and advantages of the present invention will become clearer from the following specification of a preferred embodiment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a perspective view of the selectively deployable cupholder according to the present invention, shown in the undeployed state and integrally formed at a top surface of an automotive trim component.
FIG. 1B is a perspective view of the selectively deployable cupholder according to the present invention, shown in the deployed state and operatively with respect to the automotive trim component and a beverage container.
FIG. 2 is a perspective view of the selectively deployable cupholder according to the present invention, shown in the undeployed state and integrally formed at the bottom of a well of another automotive trim component.
FIG. 3 is an exploded perspective view of the selectively deployable cupholder according to a first embodiment of the present invention, wherein the bosses are static and the detents are resilient.
FIG. 4 is a partly sectional view, seen along line 4 — 4 of FIG. 1 A.
FIG. 5A is a sectional view, seen along line 5 A— 5 A of FIG. 4 .
FIG. 5B is a sectional view, seen along line 5 B— 5 B of FIG. 4 .
FIG. 6 is a fragmentary, partly sectional side view of the inside wall surface of a stationary cylindrical component according to the first embodiment of the present invention, showing in particular a track thereof.
FIG. 7 is a fragmentary, partly sectional, perspective view, seen at circle 7 of FIG. 6 .
FIG. 8 is a fragmentary, partly sectional, perspective view, seen at circle 8 of FIG. 6 .
FIG. 9 is a fragmentary, sectional view, seen along line 9 — 9 of FIG. 8 .
FIG. 10 is a perspective view of a stationary cylindrical component according to the first embodiment of the present invention adapted for removable interface with respect to a complementary trim component.
FIG. 11 is a sectional side view of the stationary cylindrical component of FIG. 10, seen removably interfaced with a complementary trim component.
FIG. 12 is a perspective view of a stationary cylindrical component according to a second embodiment of the present invention for operation with respect to static detents and resilient bosses, a removable configuration, similar to that of FIG. 10, being exemplarly shown.
FIG. 13 is a partly sectional view, seen along line 13 — 13 of FIG. 12 .
FIG. 14 is a perspective view of a first version of movable cylindrical component according to the second embodiment of the present invention.
FIG. 15 is a partly sectional view, seen along line 15 — 15 of FIG. 14 .
FIG. 16 is a partly sectional view, seen along line 16 — 16 of FIG. 14 .
FIG. 17 is a perspective view of a second, most preferred, version of movable cylindrical component according to the second embodiment of the present invention.
FIG. 18 is a partly sectional view, seen along line 18 — 18 of FIG. 17 .
FIG. 19 is a partly sectional view, seen along line 19 — 19 of FIG. 17 .
FIG. 20 is a partly sectional view, seen along line 20 — 20 of FIG. 17 .
FIG. 21 is a sectional view, seen along line 21 — 21 of FIG. 17 .
FIG. 22 is a sectional view, showing track and boss interaction according to the second embodiment of the present invention.
FIG. 23 is a sectional view, showing detent and boss interaction according to the second embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the Drawing, FIGS. 1A and 1B depict an example of a selectively deployable cupholder 100 according to the present invention. A stationary cylindrical component 102 is either intergrally connected (for example by injection molding) or attachably connected (for example by sonic welding or adhesive) to an upper surface 104 U of an automotive trim component 104 . The automotive trim component is, by way of example, a drawer which slides (see arrow S) in and out of an opening 104 P of another trim component, such as for example a console 104 C. The stationary cylindrical wall 106 of the stationary cylindrical component is in upstanding relation to the upper surface 104 U. A lower end 106 L of the stationary cylindrical wall 106 is connected to a floor. The floor may be, for example integral with the trim component or integral with the stationary cylindrical wall, and may be continuous (see 142 of FIG. 4 ), or may be discontinuous (for example, having a central opening with a perimeter ledge for engaging a beverage container). A movable cylindrical component 108 is telescopically nested inside the stationary cylindrical component 102 , and is telescopically movable with respect to the stationary cylindrical component from an undeployed state, as shown at FIG. 1A, to a deployed state, as shown at FIG. 1 B.
When in the undeployed state, the selectively deployable cupholder 100 has a very low vertical silhouette in that the movable cylindrical component 108 is nested fully into the stationary cylindrical component 102 (to the extent of all but a lip 112 of the movable cylindrical component), which allows for an unobstructed and unobtrusive presence in the passenger compartment of a motor vehicle, and further is nicely adaptable for placement at a drawer which is slidably stowable into, for example, a console. When at the deployed state, the depth provided by the vertical combination of the stationary and movable cylindrical components 102 , 108 provides excellent support for a beverage container 110 with good stability even as customary inertial forces are encountered during driving. In this regard, the beverage container rests upon the floor (see the floor 142 at FIGS. 4 and 5 B).
The lip 112 (which is preferred, but optional) of the movable cylindrical component 108 may include circumferential knurling K or indents 114 to aid a user to grip the lip and thereby execute its rotation during telescoping of the movable cylindrical component 108 relative to the stationary cylindrical component 102 . A notch 116 may be provided in the movable cylindrical component 108 at the movable cylindrical wall 122 adjacent the upper end 112 U thereof, inclusive of the lip 112 , for receiving a handle 110 H of the beverage container 110 .
FIG. 2 depicts a variation of FIGS. 1A and 1B, in that an automotive trim component 104 ′ now has a significant thickness such that the selectively deployable cupholder 100 is located within a well 104 W of the trim component. Preferably, the well 104 W has sufficient depth to completely receive the vertical height of the selectively deployable cupholder 100 when in the undeployed state, as shown at FIG. 2 . The well 104 W has a generous diameter which is sufficiently larger than the diameter of the lip 112 such that a person may easily place his/her fingers/thumb onto the lip to cause deployment of the moveable cylindrical component 108 without interference by the trim component 104 ′.
A preferred structure for carrying out the telescopic movement of the movable cylindrical component 108 relative to the stationary cylindrical component 102 according to a first embodiment of the present invention will now be described with additional reference to FIGS. 3 through 9.
As best shown at FIG. 3, the movable cylindrical component 108 is provided with a plurality of bosses 118 emanating, in perpendicular relation, from the outer wall surface 120 of the movable cylindrical wall 122 adjacent the lower end 122 L thereof. The inner wall surface 124 of the stationary cylindrical wall 106 of the stationary cylindrical component 102 has a plurality of tracks 126 having a concave track wall 126 W formed thereinto, one track, respectively, for each boss 118 . As best shown at FIG. 6, each track 126 is helically oriented from a lower horizontal track section 126 L, whereat is a lower detent 128 located adjacent the lower end 106 L of the stationary cylindrical wall 106 , to an upper horizontal track section 126 U, whereat is an upper detent 130 located adjacent an upper end 106 U of the stationary cylindrical wall. The helical orientation of the tracks 126 provides a guide path for the movable cylindrical component 108 to be rotated while being telescopically raised/lowered relative to the stationary cylindrical component 102 . Each boss 118 is received into its respective track 126 , wherein the tracks guide rotation R (see FIG. 4) and telescopic movement of the movable cylindrical component 108 with respect to the stationary cylindrical component 102 , as can be understood by referencing FIGS. 4 through 5B, wherein there is a freely slidable fit between the inner wall surface 124 and the outer wall surface 120 (see FIGS. 5 A and 5 B).
In the example shown, three bosses 118 are provided, equally spaced around the perimeter of the outer wall surface 120 , and three corresponding tracks 126 are provided also equally spaced around the perimeter of the inner wall surface 124 . Three bosses/tracks 118 / 126 are preferred as this distributed number provides a three dimensional guidance of the movable cylindrical component 108 , although the number may be other than three.
The lower and upper detents 128 , 130 are provided at each track for defining the lower and upper telescopic limits of travel, respectively, of the movable cylindrical component 108 with respect to the stationary cylindrical component 102 . In this regard, each detent 128 , 130 has a concavity 132 which provides a snapping placement thereinto of its respective boss 118 , whereby the user detects (feelingly and, if so designed, audibly), in a feedback manner, achievement of a limit of telescopic travel.
As shown at FIGS. 6, 7 and 8 , the concavity 132 is, in one form, provided by a pair of mutually separated protuberances 132 P and is sized with respect to the cross-section of the track 126 so as to fully receive the boss 118 without strain, whereby plastic creep is prevented at the lower and upper detents 128 , 130 . In this regard, the width of the tracks 126 is preferably just about the diameter of the bosses 118 , the diameter of the tracks at the protuberances 132 P is less than the diameter of the bosses, and the diameter of the track at the apex 132 A of the concavity 132 is at least equal to the diameter of the bosses. As shown at FIG. 3, it is also contemplated to provide a width of the tracks 126 sufficiently less than the diameter of the bosses 118 that the snapping action at the detents 128 , 130 occurs without the presence of the protuberances, again, the tracks at the concavities being at least as wide as the diameter of the detents.
The snapping action of the lower and upper detents 128 , 130 is provided by upper and lower resilient fingers 134 , 136 , respectively flexing as the bosses 118 move past the protuberances 132 P. The upper resilient finger 134 is shown at FIG. 7, wherein a cut-out 140 is provided in the wall of the stationary cylindrical component 102 which communicates with the adjoining track 126 . The lower resilient finger 136 is shown at FIGS. 8 and 9, wherein a floor 142 of the stationary cylindrical component 102 has a reduced thickness portion 144 at a cut-out 146 that communicates with the adjoining track 126 .
FIGS. 10 and 11 depict a variation in the selectively deployable cupholder 100 ′ according to the present invention, wherein the stationary cylindrical component 102 ′ is removably seated with respect to a complementary trim component 104 ″. Removability of the stationary cylindrical component 102 ′ affords the user an easy methodology for cleaning in the event of an inadvertent beverage spillage. In the example depicted, a tab 150 is provided in perpendicular relation to an outside wall surface of the stationary cylindrical component 102 ′.
Oppositely positioned on the outside wall surface is a resilient arm 152 , including a barb 154 . In operation, the complementary trim component 104 ″ has an opening 156 into which is received the stationary cylindrical component 102 ′, wherein a pocket 158 of the trim component firstly receives the tab 150 and thereafter the barb resiliently locks into an oppositely located slot 160 . The pocket 158 and the slot 160 prevent rotation of the stationary cylindrical component by interference with the tab 150 and the resilient arm 152 , respectively.
The hereinabove recounted first embodiment of the present invention involved static bosses on the movable cylindrical component and resilient detents on the stationary cylindrical component, wherein the detents have an axial orientation with respect to the tracks (by “axial orientation” is meant that the concavity is formed in the tracks parallel to the cylindrical axis of the movable cylindrical member). Hereinbelow is recounted a second preferred embodiment of the present invention, wherein the bosses are resilient on the movable cylindrical component and the detents are static on the stationary cylindrical component, wherein the detents have a radial orientation with respect to the tracks (by “radial orientation” is meant that the concavity is formed in the tracks radial to the cylindrical axis of the movable cylindrical member).
FIG. 12 depicts an example of the static cylindrical component 202 according to the second embodiment of the present invention. While a removable version is shown which operates with respect to a complementary trim component similarly to that described with respect to FIGS. 10 and 11, the stationary cylindrical component 202 may be configured with respect to trim components similar to that described with respect to FIGS. 1A through 4.
The static cylindrical component 202 now has tracks 226 formed in the inner wall surface 224 of the stationary cylindrical wall 206 which are differently configured from the tracks 126 depicted in the first embodiment. In this regard, each track 226 has a concave shaped wall 226 W, and is helically oriented from adjacent an upper end 206 U of the stationary cylindrical wall 206 to adjacent a lower end 226 L of the stationary cylindrical wall (without the upper and lower horizontal sections of the first embodiment), wherein the lower and upper detents 228 , 230 are semi-circular concavities 232 which are deeper than the concave shaped wall 226 W (as shown best at FIG. 13 ). As mentioned hereinabove with respect to the first embodiment of the present invention, three tracks 226 are preferred.
FIGS. 14 through 21 depict two variations of the movable cylindrical component 208 , 208 ′, wherein the bosses 218 thereof are resilient.
FIG. 14 depicts a variation of the movable cylindrical component 208 in which the bosses 218 are radially resilient, via each boss 218 being mounted at a distal end of a vertically oriented resilient arm 270 , whereby the boss is located adjacent the lower end 222 L of the movable cylindrical wall 222 , as shown additionally by FIG. 15 . One boss 218 is provided for each track 226 .
FIG. 16 depicts that the movable cylindrical wall 222 is U-shaped, having an annular spacing 222 S at the lower end 222 L, and such that the outer wall surface 220 is flush with the resilient arm 270 . The spacing 222 S allows for radially resilient movement of the bosses.
FIG. 17 depicts another variation of the movable cylindrical component 208 ′ in which the bosses 218 are radially resilient, via each boss being mounted centrally upon a tangentially oriented resilient arm 272 which is connected at each end to the movable cylindrical wall 222 ′ (alternatively, only one end of the resilient arm may be connected). Each boss 218 is located adjacent the lower end 222 L′ of the movable cylindrical wall 222 ′, as shown additionally by FIG. 20 . As shown best by FIGS. 19 and 21, the resilient arm 272 is separated from the outer wall surface 220 ′ at an indentaton 220 I thereof. The separation 276 allows for the radially resilient movement of the bosses. FIG. 21 depicts the resilient arm 272 in a relaxed state. One boss 218 is provided for each track 226 .
FIG. 22 depicts the interaction between the concavely shaped wall 226 W of a track 226 and a boss 218 . FIG. 23, on the other hand, depicts the boss 218 now located at a semi-circular concavity 232 of a detent 228 , 230 . It will be noted that FIG. 22 depicts a first flexed state of the resilient arm and FIG. 23 depicts a second flexed state of the resilient arm, wherein the first flexed state (of FIG. 22) is more flexed than the second flexed state (of FIG. 23 ), and the second flexed state is somewhat flexed relative to the relaxed state (of FIG. 21 ), which is unflexed.
Since the concavity 232 of the detents 228 , 230 are concavely semi-circular, since the bosses 218 are convexly semi-circular, and since the flexible arms are flexed in the first state at the tracks and flexed in the second state at the detents, the bosses tend to snappingly center into the detents in a manner detectable to the user as the user rotates the movable cylindrical component relative to the stationary cylindrical component.
It will be noted from inspection of FIGS. 14 and 17 that a lip is absent, whereas present is a series of regularly spaced indents 274 . While a lip may be applicable to the movable cylindrical component 208 , 208 ′ of the second embodiment, likewise the absence of a lip is applicable to the movable cylindrical component 108 of the first embodiment.
A preferred material for the stationary and movable cylindrical components is a low friction plastic material, such as acetal.
The tracks 126 , 226 may be open at the upper end of the stationary cylindrical wall, as shown for example at FIGS. 6 and 12, or may be closed as shown at FIG. 10 . In the event the tracks are closed, the bosses are press fit into the tracks at the time of manufacture.
While a single selectively deployable cupholder has been shown relative to a trim component, it is preferred to provide a set of two selectively deployable cupholders.
To those skilled in the art to which this invention appertains, the above described preferred embodiment may be subject to change or modification. Such change or modification can be carried out without departing from the scope of the invention, which is intended to be limited only by the scope of the appended claims. | A selectively deployable cupholder that incorporates the best aspects of the static and active component cupholder designs, composed of stationary cylindrical component and a movable cylindrical component that is telescopically nested within the stationary cylindrical component. When the movable cylindrical component is in an undeployed state, whereat it is fully nested with respect to the stationary cylindrical component, a low vertical profile is provided, suitable for drawer applications. When the movable cylindrical component is in a deployed state, whereat it is fully telescopically raised relative to the stationary cylindrical component, the cupholder receives beverage containers with a stable support as is required for the automotive driving environment. | 1 |
FIELD OF THE INVENTION
A process and composition for decorating a dyed cloth fabric, more specifically, a process of using a silkscreen or other stencil and an oxidizing gel to remove from the fabric workpiece dye reactive with the oxidizing gel, the removal duplicating the silkscreen or stencil pattern.
BACKGROUND OF THE INVENTION
Serigraphy is the making of silkscreen prints. A piece of silk, nylon, monofilament polyester, multifilament polyester, organdy, or other suitable material is stretched over a frame. The material has open mesh and mesh blocked in selected areas and thus acts as a screen or stencil, the unblocked areas for allowing ink to pass through the fabric on the underlying surface to be printed. Ink or other pigment carrying medium is typically poured over the screen and then scrapped, with a squeegee or the like over the fabric. This forces the ink or pigment through the unblocked mesh to transfer the ink or pigment to the fabric in a pattern reflecting the silkscreen pattern.
Applicants provide, however, a silkscreen, including fabric and emulsion, that will not react with or be damaged by the presence of an oxidizer, such as bleach, as well as a gel bleach composition of suitable viscosity such that it will pass through the open pores of the silkscreen and not run or migrate horizontally in the fabric yet to be blocked by the nonporous regions of the silkscreen. Thus, applicants provide a method and composition suitable to decorate a dyed fabric, such as indigo dyed cotton denim, by dye removal.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide a composition suitable for use with a silkscreening method, which composition is comprised of a two-phase colloidal suspension of a solid and a liquid, typically a gel containing an oxidizer. The oxidizer is reactive with the dye of the fabric workpiece such that, when the gel composition is applied through the silkscreen to the workpiece, dye removal is effective to transfer the pattern from the silkscreen to the fabric workpiece.
It is a further object of the present invention to provide a method for transferring an aesthetically pleasing pattern from a silkscreen, stencil, or the like onto a dyed fabric, utilizing the silkscreen or stencil in conjunction with an oxidizing composition of suitable viscosity to penetrate the mesh of the silkscreen or a stencil through to the fabric workpiece beneath.
SUMMARY OF THE INVENTION
Applicants' unique composition is typically comprised of a liquid oxidizing agent, such as sodium hypochlorite or potassium permanganate, and a thickening or gelling composition. Typically, water is mixed with a thickening or gel agent, to which the oxidizer is added, to an effective viscosity such that it can effectively oxidize a fabric workpiece when urged through the openings of the mesh of a silkscreen or stencil.
Applicants' novel method is comprised of silkscreening or stenciling onto a fabric workpiece comprised of a dye reactive with an oxidizer, a gel composition of suitable viscosity and capable of reacting with the dye to create an aesthetic pattern more reflective of the silkscreen onto the fabric workpiece.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Silkscreening is a well-known process by which a screen or mesh is covered or blocked in negative or positive image areas while leaving image areas of the screen open so that printing inks or pigments may pass through the screen in the open mesh image areas to produce an image on a surface immediately behind the screen. To make a suitable printing screen, mesh of silk, monofilament polyester, organdy, multi-filament polyester, nylon, or other suitable materials is stretched taut across a frame and affixed to the edges to prevent the mesh from sagging during the printing process.
There have been a number of methods of producing non-photographic screens. For example, paper stencils are cut to create a negative image, the paper then adhered to the screen, and printing ink is passed through uncovered image areas to create the positive image on the surface behind the screen.
Blockout is a method used to create a silkscreen by applying a masking material to the desired negative image areas of the screen. The blockout material may consist of a glue, shellac, or other material not affected by the screen printing ink, but able to clog the screen.
Another method of making a non-photographic stencil is with hand cut film of gelatin-like layers applied evenly over a paper or plastic film. The layers are hand cut with a sharp blade. The image desired and the gelatin are adhered to the mesh with solvent or with water. Once it's adhered and dried, the backing sheet is peeled off the screen leaving the cut image to create the stencil.
Another process for preparing an imaging screen involves the use of photosensitive coatings, referred to as emulsions, to coat the screen. The emulsions contain polymers which cross-link when exposed to light in the visible or ultraviolet frequencies. The photosensitive emulsions are coated on meshes or screens which are then stretched tightly across the frame under darkened or safe life conditions. Emulsions are allowed to dry. Any obliterating material, such as an opaque film positive, is then placed over the screen for shielding imaging areas of the screen and the screen is then exposed to radiant light, causing the polymers to react in the exposed negative areas of the screen. The exposed areas are adhered to the mesh. The non-exposed emulsion is subsequently selectively removed from the screen by, for example, washing the screen with warm water. After the screen is dried, the screen can be used for printing, with ink passing through image areas from where the non-exposed emulsion has been removed.
These and other methods for preparing silkscreen, nonreactive with the chemicals and oxidizers of applicants' preferred composition, are anticipated. The silkscreen so produced is stretched tightly across a frame in ways known in the trade. The fabric workpiece, typically dyed cloth comprising a garment, such as a shirt or a jacket, is placed beneath the silkscreen. The screen is urged directly against the flat laying fabric and the application of applicants' unique gel oxidizing composition is then in order.
In order to bleach or oxidize the fabric following the preparation of the silkscreen stencil by any of the methods set forth above or any method known in the art, the work piece, typically but not necessarily indigo dyed cotton denim, is placed beneath the silkscreen with the ladder pressed firmly against the surface of the work piece. The gel is then placed along one end edge of the silkscreen and squeegeed across. The gel, if of the proper viscosity, will be forced through the openings in the mesh and blocked from those areas in which the mesh is impervious.
The preferred composition of the present invention is a two-phase (solid dispersed throughout a liquid medium) colloid suspension, typically a gel composition containing an oxidizing agent, typically in the liquid state, and a dispersed gelling or thickening agent. The preferred oxidizing agents (non-reactive with the silkscreen) are hypochlorites, chlorites, and permanganate oxidizers. Early indications show that the permanganate oxidizers do not adversely affect the screen as much as the chlorine-based oxidizers. Nor are the gelling agents intended to be limited to the specific embodiments enclosed. Indeed, both organic and inorganic gelling agents have been disclosed and used in the compositions and methods set forth herein. The specifications and claims are intended to apply to combinations of gelling compositions and oxidizers regardless of their origin and nature. The preferred gelling agents are nonorganic smectite clays, aluminum silicates, attapulgite clay, silicon dioxide, fumed silica, colloidal silicas, modified montmorillonite clay, and amorphous silica powder.
To provide the proper consistency to the composition, applicants utilize a gelling or thickening agent which is typically derived from either organic or inorganic sources. Particularly useful as gelling agents in applicants' invention are natural smectite clays; such as magnesium aluminum silicates; and bentonite clays. A gel may be made in a variety of ways, but the gel used by applicants will typically substantially cling to a vertical surface and has a preferred viscosity range.
A gel is a two-phase colloid in which the disperse phase (solid) has combined with the continuous phase (liquid) to produce a viscous jelly-like product. The gel dispersion, typically of a solid and liquid may range from nearly liquid to the solid state, but is typically a semi-solid and of a jelly-like consistency, such as gelatin, mucilage, uncooked egg-white and the like.
Typically, gel solutions' viscosity depends upon their previous treatment. If the solution has been subject to large shear forces (such as being agitated or stirred rapidly), its fluidity is changed. But after some time, it returns to its former, more viscous condition. Gels also typically exhibit elasto-plastic deformation.
A great portion of the gel volume is typically occupied by a liquid (dispersion medium). Typically, the dispersed medium is a small percent of the liquid by both weight and volume of the gelling agent to the liquid. Often, where the liquid phase is water, it retains the ability to diffuse small molecules, such as a bleaching or oxidizing agent, throughout the liquid component without reacting to the gelling agent.
Here, applicants use the oxidizing agent and gelling agent to produce a gel composition of appropriate viscosity that, when transferred to a dyed garment by silkscreen, produces a pleasing effect by bleaching those areas of fabric beneath the open mesh or cutout portion.
That is, applicants' unique colloidal composition will substantially penetrate the unblocked mesh of the fabric during the transfer step of the silkscreening process. However, the composition is not so fluid that it will run horizontally across the fabric workpiece.
Among applicants' preferred gelling agents are the inorganic smectite clays such as VEEGUM and VAN GEL, products of the R. P. Vanderbilt Company, Inc., 30 Winfield St., Norwalk, Conn. 06855 which are known to persons skilled in the art. Both VEEGUM and VAN GEL are complex colloidal magnesium aluminum silicates. VEEGUM is used in some formulations as a suspending agent, emulsion stabilizer and viscosity modifier. It is supplied as an insoluble flake which forms colloidal dispersions in water. VAN GEL is an industrial thickener and suspending agent developed for industrial and agricultural uses. It is supplied as a small flake which disperses in water easily with high shear mixing. A description of these and other properties of VEEGUM and VAN GEL may be found in a folder entitled, "Minerals and Chemicals For Industry From The Specialties Department of R. T. Vanderbilt Company, Inc." #786 available from Vanderbilt. Gelulite, lapitonite (synthetic clay), bentolites, mineral colloid, asterben (sodium bentonite)--all from Southern Clay, Inc.
VEEGUM and VAN GEL have heretofore been used in the development of new household and institutional cleaning products for applications including basin, tub and tile, oven and grill, rug, toilet bowl cleaners, and paint and varnish removers, in part because they have excellent resistance to attack and degradation by strong acids, bases, and oxidizing agents. VEEGUM and VAN GEL are not soluble in water but can be dispersed in water to form a colloidal structure similar to a "house of cards". The colloidal "house of cards" structure accounts for the ability of these compositions to thicken and develop yield value in the products which they are contained. Yield value provides a vertical surface cling to the formulations while thickening provides different pouring and flow properties.
While this method and this composition, indeed the specifications of this application, frequently refer to the treatment of garments and in particular, the treatment of cotton-based fabric such as denim, the method and compositions described and claimed herein are in no ways so limited. The methods and compositions may be used with fabric before that fabric is cut up and sewn into garments. The methods and compositions claimed also apply to fabric other than cotton-based fabric, including but not limited wholly or partially synthetic fabrics and including fabrics that are combinations of synthetic and organic fibers.
The blending order of the ingredients is, typically, mixing water and the thickening or the gelling agent, here preferably VEEGUM®, VAN GEL®, or Bentonite WH. Some gelling or thickening will be seen to occur after several minutes of stirring. Following the blending of the water and the gelling or thickening agent, solid potassium manganate (oxidizer) is added as well as any stabilizers or accelerators and continued mixing takes place until the desired viscosity is reached.
Stabilizers are used to slow down the deterioration of the activity of the bleach when chlorine-based oxidizers are used. Stabilizers include compositions such as soda ash added in about 4% by weight of the composition, which has been shown to help maintain chlorine activity while the composition is in storage and gives the composition more body.
An additional component may be added to the gel composition to adjust the pH. For example, acetic acid has been found to be effective in reducing the pH of the gel composition when such reduction is called for. Altering the pH of the workpiece before it gets silkscreened with the composition will affect the action of the oxidizer.
Having discussed in general a typical blending order of the ingredients of applicants unique composition, attention will now be turned to preparing a large working batch. This particular batch was mixed in a steel tank, 160 gallon capacity with two 3-blade props, 16 inches in diameter, and driven by a 1/3 horsepower electric motor. One hundred thirty (130) gallons of water at 150° F. is provided, into which is mixed approximately 125 pounds of Bentonite WH as a gelling agent. This is mixed for approximately 1 hour in a lightning mixer. There will be some thickening of the water achieved, typically to approximately 1,000 cps or so.
About 17 pounds of dry sodium bicarbonate powder mixture is mixed in, the mixing continuing for about 15 minutes during which the composition thickens, typically to 1,500 to 2,000 cps.
Following the addition of sodium bicarbonate, potassium permanganate, the oxidizer (approximately 23 pounds) is added to the tank and mixed for about 25 minutes.
By varying the amount of gelling or thickening agent, the viscosity resulting from the mix will be preferably between 6,500 and 50,000 cps as measured in a 600 ml beaker at 72° F. using a Brookfield Model RD Viscometer with a No. 4 Spindle at 20 rpm. The general range of viscosities for applicants two-phase suspension is between 3,000 and 35,000 cps.
The second, albeit smaller, working recipe utilizes a chlorine-based bleach and includes mixing 28.6 pounds of water at 150° F. with about 6.0 pounds of Bentonite WH and 1.4 pounds of powder soda ash. The oxidizer is dry calcium hypochlorite, 65% available chlorine and the mixture is then added together in the same order as set forth previously (first adding the water to the Bentonite WH to thicken it, followed by the addition of soda ash, then sodium hypochlorite). The mixture results in a composition having about 12,000 cps viscosity and 5.5% available chlorine. When using the chlorine-based oxidizer, the preferred activity of the composition is 0.10 percent to 6.5 percent available chlorine by weight. It is preferable that the pH of applicants' composition be between 4 and 13.
Typical mesh size for silkscreen are: 80, 120, 150, 155, and 280. Typically, a coarse mesh is between 60 and 90, medium mesh between 125 and 144, and a fine mesh above 280. The preferred mesh for applicants present invention is a coarse or medium mesh used with the gel composition with a viscosity range of 3,000 to 50,000, preferably between 10,000 to 40,000 cps.
An example of an appropriate silkscreen nonreactive with applicants' potassium permanganate formulation is a silkscreen made of polyester material, having an oil emulsion applied by ways known in the art. The silkscreen is stretched across a frame. A gel composition comprising potassium permanganate as the oxidizing agent and Bentonite WH as the gelling agent and mixture to a viscosity of approximately 35,000 is applied to the 110 mesh screen and squeegeed across the screen onto an underlying indigo dyed denim garment. The squeegee used is 70 Durometer hardness and an appropriate amount of pressure is utilized to force the gel composition through the unobstructed mesh.
Following the application of the gel to the garment, the garment is post-washed by the following process:
Step 1: gel is to be antichlored or neutralized;
Step 2: garment is rinsed or scoured;
Step 3: garment is rinsed or softener is added;
Step 4: garment is extracted and dried.
Although the invention has been described in connection with the preferred embodiment, it is not intended to limit the invention's particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalences that may be included in the spirit and scope of the invention as defined by the appended claims. | A processing composition for decorating a dyed cloth fabric. The composition is a dye reactive oxidizer carrying gel and the method of use is to silkscreen onto the fabric to be decorated with the oxidizing gel. The gel is allowed to react with the dye of the fabric in a pattern dictated by the silkscreening pattern. The oxidizing agent is then removed from the fabric. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to a numerical control device (hereinafter referred to as an "NC device") for use with a machine tool, for example, and more particularly to an NC device including a graphic display unit.
NC machining devices machine a workpiece by specifying the position of a tool with respect to the workpiece in the form of corresponding numerical information. The NC machining device can machine workpieces of complex configuration with ease and high accuracy at a high production rate.
FIG. 1 of the accompanying drawings schematically shows a general machine tool controlled by a conventional NC device, the machine tool being a lathe by way of illustrative example. A cylindrical workpiece 11 fixedly clamped by a chuck 10 rotatable about a Z-axis has one end supported by a tip 12a of a tailstock 12. A cutting tool 14 is secured to a turret or tool base 13. For cutting the workpiece 11, the turret 13 is moved in the direction of the arrow Z to cause the cutting tool 14 to cut the workpiece 11.
Where the NC device includes a graphic display unit, the shape of the workpiece 11, a cutting path of the tool 14, and a finished shape of the workpiece 11 are displayed on the display unit for checking and machining program for possible interference between the workpiece and the tool and monitoring the cutting condition. The machining program is checked by displaying the tool path as indicated by dotted lines as shown, for example, in FIG. 2 of the accompanying drawings. Whether the workpiece and the tool interfere with each other or not is checked by the determined values of functions which express the shape and position of holder mechanisms composed of the chuck and tailstock. However, since the holder mechanisms have not been displayed as graphic patterns, it has heretofore not been possible to visually check for any interference between the workpiece and the tool through graphic representation.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an NC device capable of automatically converting the shape of holder mechanisms of a lathe, such as a chuck and a tailstock, into a shape of a tool for holding a workpiece shape and displaying such a converted shape by processing data indicative of the shape of the workpiece.
The above object can be achieved by a numerical control device comprising a controller for controlling a machine tool having first and second holder mechanisms for jointly holding a workpiece, the controller having means for displaying the workpiece as automatically held by the first and second holder mechanisms on a graphic display unit in accordance with the dimensional details of the workpiece, dimensional details of the first holder mechanism, and dimensional details of the second holder mechanism entered into the controller.
The above and other objects, features and advantages of the present invention will become more apparent from the following description when taken in conjunction with the accompanying drawings in which a preferred embodiment of the present invention is shown by way of illustrative example.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a lathe to which a conventional NC device is applied;
FIG. 2 is a schematic view explanatory of the checking of a machining program for the lathe shown in FIG. 1;
FIGS. 3A and 3B are views showing the relationship between a workpiece shape and a chuck;
FIG. 4 is a schematic diagram showing dimensional details of a chuck and a tailstock;
FIGS. 5A and 5B are diagrams showing coordinate data for graphic display;
FIG. 6 is a diagram depicting the relationship between a reference coordinate system and a local coordinate system;
FIGS. 7A and 7B are diagrams illustrating the concepts of an absolute coordinate system and a relative coordinate system, respectively;
FIG. 8 is a flowchart of processing steps according to the present invention;
FIG. 9 is a block diagram of a hardware system used for executing the process illustrated in FIG. 8; and
FIGS. 10A and 10B are schematic views showing the relationship between a workpiece shape and a tailstock.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
According to the present invention, holder mechanisms such as indicated by reference numerals 10, 12 in FIG. 1 are displayed. A specific arrangement of the present invention will hereinafter be described.
FIGS. 3A and 3B are illustrative of graphic patterns such as that of a lathe to be applied to a graphic display unit. A first holder mechanism is composed of a chuck 10 and chuck jaws 10a for holding a workpiece 11. In case the chuck 10 is displayed as fixed in position, there is an instance where the workpiece 11 cannot be held by the chuck 10 as shown in FIG. 3A since the workpiece 11 may not be constant in shape and size. Dependent on the shape and size of the workpiece 11, the graphic pattern is converted so that the chuck jaws 10a will be moved so as to be able to hold the workpiece 11. FIG. 3B illustrates the graphic pattern as thus converted.
A second holder mechanism is composed of a tailstock 12 having a tip 12a as shown in FIGS. 10A and 10B.
For a better understanding of the present invention, FIG. 4 shows dimensional details of the first and second holder mechanisms. Denoted in FIG. 4 at X 1 -X 8 are dimensional details of the first holder mechanism, and Y 1 -Y 7 dimensional details of the second holder mechanism.
An appropriate example of graphic pattern conversion will be described with reference to FIGS. 5A and 5B.
Data items to be displayed as graphic patterns are all expressed as coordinate data items as shown in FIGS. 5A and 5B. In FIGS. 5A and 5B, coordinate data items for the chuck 10 are indicated by P n (n=1 through 6) and coordinate data items for the chuck jaw 10a are indicated by q n (n=1 through 6), with p 1 , q 1 serving as reference coordinates and p n , q n (n=2 through 6) as relative coordinates from p 1 , q 1 .
The relative coordinates are used for the reason that, with such relative coordinates, if a reference point is positionally changed, then all points in a certain coordinate system having such a reference point as a reference will be renewed, but with all points expressed only by absolute coordinates, if a positional change were to be made, the extent of such a positional change would have to be computed for all points in the absolute coordinate system.
Reference coordinates will be simply described. Reference coordinates means an origin of a local coordinate system as shown in FIG. 6. The reference coordinates are indicative of a single coordinate set or value when viewed from an outer coordinate system.
With such a coordinate data construction, the coordinates can be indicated as shown in FIGS. 7A and 7B. Designated at p 1 in FIG. 7A is a reference point, while the other points are representative of values of an absolute coordinate system with p 1 being the origin. FIG. 7B shows a relative coordinate system having the reference point p 1 as the origin. As shown in FIGS. 7A and 7B, when a graphic pattern of p n (n=1 through 4 in the illustrated example) is to be moved, only the reference coordinates p 1 are renewed, and offsets (p 2 through p 4 ) are added to the reference coordinates p 1 to translate the same for thereby obtaining actual coordinates, whereupon the pattern is displayed.
The reference coordinates p 1 , q 1 of the chuck 10 and the chuck jaw 10a as shown in FIGS. 5A and 5B can be determined by an algorithm illustrated in FIG. 8. The algorithm of FIG. 8 is executed by a system shown in FIG. 9 which operates as follows:
Data items indicative of the shape of the holder mechanism and of the diameter of the workpiece are entered through a input unit of the NC device and stored in a memory. Based on these data items, a CPU computes the position of a chuck jaw, generates a pattern corresponding to the shape thereof, and displays the same on a display unit.
The flowchart of FIG. 8 is composed of successive steps 1 l through 5. A workpiece shape and a chuck shape are entered as coordinate data items in step 1. Coordinates on the outside diameter of the workpiece shape at the chuck are established as a reference point for the chuck jaw in the step 2. A point on the central axis which is spaced a distance Z 1 (FIG. 5B) from the end of the workpiece which faces the chuck is regarded as a reference point for the chuck in step 3. Actual coordinates can be determined by adding relative coordinates to the reference points thus defined in step 4. A chuck shape converted through linear interpolation of the actual coordinates is completely displayed together with the actual machining condition in step 5.
FIGS. 10A and 10B are illustrative of the display of the tailstock 12 or the second holder mechanism. Reference coordinates r 1 (FIG. 10A) can be established as shown in FIG. 10B by setting a workpiece end surface S on the Z-axis and setting X at "0" (on the Z-axis). The following process is the same as described with respect to the chuck 10, i.e., the shape of the tailstock is defined by a local coordinate system, and the tip of the tailstock is given by reference coordinates, which are translated and displayed.
While in the foregoing embodiment the NC device has been described as being used with a lathe, the present invention is applicable to NC devices used in combination with various other machine tools such as a machining center.
Although a certain preferred embodiment has been shown and described, it should be understood that many changes and modifications may be made therein without departing from the scope of the appended claims. | A numerical control device stores dimensional details of a workpiece, a chuck, and a tailstock as coordinate data items in a memory, computes the positions and shapes of the workpiece, the chuck, and the tailstock based on the coordinate data items, and displays the workpiece, the chuck, and the tailstock as graphic patterns on a display unit based on the computed results. The computation is simplified by using coordinates of a relative coordinate system as the coordinate data items for graphic display. | 8 |
BACKGROUND
Operating temperatures of gasses in and passing from combustors of gas turbine engines are typically quite high, requiring cooled liners in the combustors and downstream thereof to avoid damage to the internal parts of the engines. Cooling is typically provided by a compressor upstream of the combustor. To maximize engine efficiency, it is desirable to use the minimal amount of cooling air necessary to maintain the integrity of the liners and not to allow any cooling air leakage.
Leakage may occur between mating or adjacent components and seals. Tight tolerances between such mating or adjacent components are typically employed to minimize such leakage.
SUMMARY OF THE INVENTION
According to a non-limiting embodiment disclosed herein, a seal for a duct having an upstream portion and a downstream portion, the duct upstream portion and the duct downstream portion separated by a first gap, includes a first portion having a length greater than a width of the first gap between the first portion and the second portion, the first portion having a first thickness, a first upstream end and a first downstream end; a second portion having a length greater than a width of the gap between the first portion and the second portion, the second portion having a second thickness, a second upstream end and a second downstream end; and an attachment between the first portion and the second portion such that the first portion and the second portion move relative to each other wherein the first portion is inside the duct and the second portion is outside of the duct.
According to any previous claim, a second gap is disposed between the first upstream portion and the second upstream portion wherein the second gap is smaller than a thickness of the duct upstream portion.
According to any previous claim, a third gap is disposed between the first downstream portion and the second downstream portion wherein the third gap is smaller than a thickness of the duct upstream portion.
According to any previous claim, a third gap is disposed between the first downstream portion and the second downstream portion wherein the third gap is smaller than a thickness of the duct upstream portion.
According to any previous claim, the first thickness is thicker than the second thickness.
According to any previous claim, the second thickness is thinner than the first thickness.
According to any previous claim, the second thickness is thinner than the first thickness and is disposed in a higher pressure environment than a lower pressure environment in which the first thickness is disposed.
According to any previous claim, each of the upstream ends and the downstream ends have rotation points that rotate the first portion and the second portion about the duct upstream portion and the duct downstream portion.
According to any previous claim, one of the first portion and the second portion are disposed radially inwardly within the duct, the one of the first portion and the second portion having an extension extending distally beyond the a rotation point on either of the upstream end or the downstream end.
According to any previous claim, the first portion and the second portion are spring loaded against the duct upstream portion and the duct downstream portion.
According to any previous claim, the attachment includes a first finger extending from the first portion towards the second portion, a second finger extending from the second portion towards the first portion, and an axle extending through the first finger and the second finger about which the first and second finger may rotate.
According to any previous claim, the second portion is segmented into first members to maintain a seal if the duct is curved wherein two adjacent members are defined by a cleft.
According to any previous claim, the cleft is covered by a band attaching to one of the adjacent first members and is forced against another of the adjacent first members by pressure.
According to any previous claim, wherein the first portion is segmented into second members to maintain a seal if the duct is curved.
According to any previous claim, wherein each the first portion and the second portion are arcuate, and a concave side of the first portion faces a concave side of the second portion.
According to a further non-limiting embodiment disclosed herein, a seal for sealing a first gap between a higher temperature, lower pressure first flow path and a lower temperature higher pressure second flow path in a gas turbine engine, the seal includes a first portion having a length greater than a width of the first gap, the first length disposed in the higher temperature, lower pressure first flow, the first portion having a first thickness, a first upstream end and a first downstream end; a second portion having a length greater than a width of the gap the second portion disposed in the higher pressure, lower temperature second flow, the second portion having a second thickness, a first upstream end and a first downstream end; and an attachment between the first portion and the second portion such that the first portion and the second portion move relative to each other.
According to any previous claim, wherein the first thickness is thicker than the second thickness.
According to any previous claim, wherein each of the upstream ends and the downstream ends have rotation points for rotating the first portion and the second portion about a first edge or a second edge, wherein the gap is formed between the first edge and the second edge.
According to any previous claim, the first portion and the second portion are spring loaded against the first edge and the second edge.
According to any previous claim, wherein the attachment includes a first finger extending from the first portion towards the second portion, a second finger extending from the second portion towards the first portion, and an axle extending through the first finger and the second finger about which the first and second finger rotate.
According to any previous claim, wherein each the first portion and the second portion are arcuate, and a concave side of the first portion faces a concave side of the second portion.
BRIEF DESCRIPTION OF THE DRAWINGS
The various features and advantages of the disclosed examples will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows.
FIG. 1 is a sectional view of a gas turbine engine that incorporates an exemplary embodiment disclosed herein.
FIG. 2 is a side-view of a seal used between adjacent ducts taken along the lines 2 - 2 of FIG. 1 .
FIG. 2A is a side-view of the seal taken along the lines 2 - 2 of FIG. 2 .
FIG. 3 is a perspective side-view of a first embodiment of the seal of FIG. 2 .
FIG. 4 is a perspective inner view of a segmented seal of FIG. 2 .
FIG. 4A is a perspective outer view of a segmented seal of FIG. 2
FIG. 5 is a side-view of the seal of FIG. 2 in operation.
DETAILED DESCRIPTION
Referring to FIG. 1 , a gas turbine engine 10 includes a fan section 12 , a compressor section 14 , a combustor section 16 , and a turbine section 18 . Air entering into the fan section 12 is initially compressed and a portion fed to the compressor section 14 . Bypass air flow 301 provides some of the propulsion force from the engine. In the compressor section 14 , the incoming air from the fan section 12 is further compressed and communicated to the combustor section 16 . In the combustor section 16 , the compressed air is mixed with gas and ignited to generate a hot exhaust stream 28 . The hot exhaust stream 28 is expanded across the turbine section 18 to drive the fan section 12 and the compressor section 14 . In this example, the gas turbine engine 10 includes an augmenter section 20 where additional fuel can be mixed with the exhaust gasses 28 and ignited to generate additional thrust. The exhaust gasses 28 flow from the turbine section 18 and the augmenter section 20 through an exhaust duct 22 . Some bypass air 302 passes within the duct 22 as cooling air. An inner liner for the exhaust duct 22 protects outer surface 82 from the hot gasses 28 escaping from the augmentor section 20 and the turbine section 18 . Of course, this application extends to engines without an augmentor section.
As one may appreciate, there may be several liners in the engine 10 . Liner 55 is in the exhaust duct 22 . Liner 60 is in the augmentor section 20 and liner 65 is in the turbine section 18 . The liners 55 , 60 and 65 , however, may be in more than one piece and are constructed generally of axial segments. For instance, duct liner 55 may have an upstream segment 75 and a downstream segment 80 (See FIG. 2 ).
Referring now to FIGS. 2-4 , the liner 55 has an upstream segment 75 and a downstream segment 80 separated by a gap 77 . Each of the upstream and downstream segments 75 and 80 has a radially inner chamfer 85 and a radially outer chamfer 90 and an edge formed therebetween 95 . A seal 100 bridges the gap between the upstream segment 75 and the downstream segment 80 . The seal 100 is shaped like a clamshell and has a radially inner half 105 , a radially outer half 110 that are both disposed radially outward from an axial centerline 115 .
The radial inner half 105 has an arcuate body 130 and radially outwardly extending fingers 135 which extend from a central area 140 of the arcuate body 130 . The arcuate body 130 is thicker than the body of the radially outer half 110 as will be discussed infra. Each finger 135 has an opening 145 near a remote end 150 thereof. Each of the fingers is separated by a distance D 1 , as will be discussed infra. The arcuate body 130 may have one or more vents 155 to prevent any pressure buildup between the radial inner half 105 and the radial outer half 110 . The arcuate body 130 has an upstream end 160 and a downstream end 165 .
Referring to FIG. 2A , each of the upstream end 160 and the downstream end 165 has a flat portion 170 that is offset from each of the streamed portion and the downstream portions 75 and 80 by an arcuate bump 175 that comes into contact with the upstream portion and the downstream portion (see FIG. 2A ). A gap 180 is formed between the flat portion and the liner to allow relative motion of the seal 100 about the upstream segment 75 and a downstream segment 80 .
The radial outer half 110 has an arcuate body 185 with radially inwardly extending fingers 190 , each of which extends outwardly from the central area 195 of the arcuate body 185 . Each finger has an h 200 near a finger remote end 205 and each of the fingers is also separated by a distance D 1 . The fingers 190 of the radial outer half mesh with the fingers 135 of the radial inner half to receive a pin 210 in the holes 200 in the radially outer half and the openings 145 and the fingers 135 of the radial inner half 105 . The pin 210 locks the radial outer half 110 to the radial inner half 105 . The arcuate bodies 130 and 185 are convex sides 187 facing each other.
The radial outer half 110 has an upstream end 215 and a downstream end 220 . Each of the upstream end and the downstream end have an arcuate bump 230 extending from the upstream end 215 and the downstream end 220 that comes in contact with each of the upstream liners 75 and the downstream segment 80 to relative motion of the seal 100 about the upstream segment 75 and a downstream segment 80 .
The arcuate body of the radial outer half 110 is thinner than the body 130 . The thinness promotes cooling of the radial outer half arcuate body 185 , while the thicker arcuate body 130 of the radial inner half 105 helps protect it from heat. Moreover, the radial outer half arcuate body 185 can be springier and thinner to enable the secondary flow 37 press the arcuate bumps 230 against the upstream segment 75 and the downstream segment 80 to provide primary sealing thereby. The secondary flow 37 is higher pressure and cooler than the hot exhaust stream 28 of gas.
In operation, the edges 95 and the radially inner chamfer and the radially outer chamfer 85 , 90 , enable the upstream ends 160 and 215 to be separated by the chamfer surfaces and allow the seal 100 to be slid across the upstream segment 75 . Similarly, the downstream segment 80 may be inserted through the arcuate bump 230 and the arcuate bump 175 of the radial inner half 105 and the radial outer half 110 . Alternatively, the radial inner half 105 and the radial outer half 110 may be placed against the upstream segment 75 and the downstream segment 80 and then compressed while the pin 210 is snaked through the openings 145 .
Because the normal spacing between the upstream ends 160 , 215 of the radial inner half 105 and the radial outer half 110 is less than the thickness of the upstream segment 75 and the downstream segment 80 , the seal 100 becomes spring loaded against the upstream segment 75 and the downstream segment 80 . Pressure from the secondary flow 37 pushes the radial outer half 110 and the contact bumps 230 against the radial upstream segment 75 and the downstream segment 80 , thereby providing the primary seal. The vents 155 minimize the probability that air will leak under the gap 180 and the arcuate bumps 175 to allow the air to pressurize the area 255 between the radial inner half 105 and the radial outer half 110 so that neither of the radial inner half or the radial outer half 110 are lifted away from the upstream segment 75 or the downstream segment 80 . Because the radial inner half 105 and the radial outer half 110 are free to rotate about the pin 235 , the parts may rotate about the pin to allow relative motion between the seal 100 and the upstream segment 75 and the downstream segment 80 (see FIG. 5 ). However, motion between the seal 100 and the upstream segment 75 and a downstream segment 80 may be limited if the gap 180 is closed and the downstream end 165 contacts either the upstream segment 75 or the downstream segment 80 .
Referring now to FIGS. 4 and 4 a , because many ducts and liners 55 have contoured shapes, the seal 100 must be able to conform to the contoured shapes. In this instance the liner 55 is annularly shaped. In order for the seal 100 to seal the gap 77 , the radial outer half 110 may be made of radial outer members 250 separated by narrow slots or kerfs 255 . A band 260 covers each slot 255 . The band 260 may be glued on one member 255 and forced against an adjacent member 255 by the secondary flow 37 to seal each slot 255 from air leakage therethrough thereby maintaining the seal.
In order for the seal 100 to seal the gap 77 , the radial outer half 110 may be made of a plurality of abutting radial outer members 250 that may be separated by narrow clefts 255 . A band 260 covers each cleft 255 . The band 260 may be glued on one radial outer member 255 and forced against an adjacent radial outer member 255 by the secondary flow 37 to seal each cleft 255 from air leakage therethrough thereby maintaining the seal. Because the seal 100 is segmented by the radial outer members 255 , the radial outer members 250 have enough bend about the clefts 255 to maintain a shape of the liner 55 while maintaining a seal.
Similarly, the radial inner half 105 may be made of a plurality of abutting radial inner members 270 that may be separated by narrow clefts 275 . Because the seal 100 is segmented by the radial inner members 275 , the radial inner members have enough flexibility to maintain a curve of the liner 55 while maintaining a seal. Because the radial inner half 105 experiences the lower pressure provided by the hot exhaust stream 28 , it is not necessary to provide band 260 on the radial inner half 105 which may also have clefts 280 about which the radial inner members may rotate to maintain a curve of the liner 55 .
Although a combination of features is shown in the illustrated examples, not all of them need to be combined to realize the benefits of various embodiments of this disclosure. In other words, a system designed according to an embodiment of this disclosure will not necessarily include all of the features shown in any one of the Figures or all of the portions schematically shown in the Figures. Moreover, selected features of one example embodiment may be combined with selected features of other example embodiments.
The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of this disclosure. The scope of legal protection given to this disclosure can only be determined by studying the following claims. | A seal for a duct having an upstream portion and a downstream portion, the duct upstream portion and the duct downstream portion separated by a first gap, includes a first portion having a length greater than a width of the first gap between the first portion and the second portion, the first portion having a first thickness, a first upstream end and a first downstream end; a second portion having a length greater than a width of the gap between the first portion and the second portion, the second portion having a second thickness, a second upstream end and a second downstream end; and an attachment between the first portion and the second portion such that the first portion and the second portion move relative to each other, wherein the first portion is inside the duct and the second portion is outside of the duct. | 5 |
FIELD OF THE INVENTION
[0001] This invention relates to a method of separating or concentrating mixtures of olefins and paraffins using a selectively permeable membrane. More specifically, it relates to a method of using certain polyimide membranes to selectively separate olefinic hydrocarbons from a gas or liquid mixture of olefinic and paraffinic hydrocarbons such as those generated by petroleum refining industries, petrochemical industries, and the like.
BACKGROUND OF THE INVENTION
[0002] Olefins, particularly ethylene and propylene, are important chemical feedstocks. Typically they are found in nature or are produced as primary products or byproducts in mixtures that contain saturated hydrocarbons and other components. Before the raw olefins can be used, they usually must be separated from these mixtures.
[0003] Currently, separation of olefin/paraffin mixtures is usually carried out by distillation. However, the similar volatilities of the components make this process costly and complicated, requiring expensive distillation columns and energy-intensive processing. Jarvelin reports that the fractional distillation of propylene/propane mixtures is the most energy-intensive distillation practiced in the United States (Harri Järvelin and James R. Fair, Adsorptive separation of propylene/propane mixtures , Ind. Eng. Chem. Research 32 (1993) 2201-2207). More energy conserving separation processes are needed.
[0004] Membranes have been considered for the separation of olefins from paraffins as an alternative to distillation. However, the separation is difficult largely because of the similar molecular sizes of the components. Another difficulty is that the feed stream conditions are typically close to the gas/liquid phase boundary of the mixture. Also, the membrane must operate in a hydrocarbon environment under conditions of high pressure and temperature. Such harsh conditions tend to adversely affect the durability and stability of separation performance of many membrane materials. For example, some contaminants plasticize selectively permeable membrane materials and can cause loss of selectivity and/or permeation rate. A membrane with sufficiently high olefin/paraffin selectivity, and sufficient durability in long-term contact with hydrocarbon streams under high pressure and temperature is highly desired.
[0005] Membrane materials for separating olefinic hydrocarbons from a mixture of olefinic and saturated hydrocarbons have been reported, but none can be easily or economically fabricated into membranes that offer the unique combination of high selectivity and durability under industrial process conditions.
[0006] For example, several inorganic and polymer/inorganic membrane materials with good propylene/propane selectivity have been studied. See M. Teramoto, H. Matsuyama, T. Yamashiro, Y. Katayama, Separation of ethylene from ethane by supported liquid membranes containing silver nitrate as carrier , J. Chem Eng. Japan 19 (1986) 1, and R. D. Hughes, J. A. Mahoney, E. F. Steigelmann, Olefin separation by facilitated transport , in: N. N. Li, J. M. Calo (eds.), Membrane Handbook, Van Nostrand, New York, 1992. Such materials are difficult to fabricate into practical industrial membranes. Liquid facilitated-transport membranes have been demonstrated to have attractive separation performance in the lab, but have been difficult to scale up, and have exhibited declining performance in environments typical of an industrial propylene/propane stream.
[0007] Solid polymer-electrolyte facilitated-transport membranes appear more amenable to fabrication into stable thin film membranes. See Ingo Pinnau and L. G. Toy, Solid polymer electrolyte composite membranes for olefin/paraffin separation , J. Membrane Science, 184 (2001) 39-48. Such a membrane is exemplified in U.S. Pat. No. 5,670,051 (Pinnau et al, 1997) wherein a silver tetrafluoroborate/poly(ethylene oxide) membrane exhibited ethylene/ethane selectivity of greater than 1000. However, these membranes are severely limited by their poor chemical stability in the olefin/paraffin industrial environment.
[0008] Carbon hollow-fiber membranes have shown promise in laboratory tests (“Propylene/Propane Separation”, Product Information from Carbon Membranes, Ltd., Israel), but are vulnerable to degradation caused by condensable organics present in industrial streams. Moreover, carbon membranes are brittle and difficult to form into membrane modules of commercial relevance.
[0009] Membranes based on rubbery polymers typically have olefin/paraffin selectivity too low for an economically useful separation. For example, Tanaka et al. report that the single-gas propylene/propane selectivity is only 1.7 for a polybutadiene membrane at 50° C. (K. Tanaka, A. Taguchi, Jianquiang Hao, H. Kita, K. Okamoto, J. Membrane Science 121 (1996) 197-207) and Ito reports a propylene/propane selectivity only slightly over 1.0 in silicone rubber at 40° C. (Akira Ito and Sun-Tak Hwang, J. Applied Polymer Science, 38 (1989) 483-490).
[0010] Membranes based on glassy polymers have the potential for providing usefully high olefin/paraffin selectivity because of the preferential diffusivity of the olefin, which has smaller molecular size than the paraffin.
[0011] Glassy polymers already used in gas separation have generally shown only modest olefin/paraffin selectivity. For example, Ito has reported that films of polysulfone, ethyl cellulose, cellulose acetate and cellulose triacetate exhibit propylene/propane selectivity of 5 or less (Akira Ito and Sun-Tak Hwang, Permeation of propane and propylene through cellulosic polymer membranes , J. Applied Polymer Science, 38 (1989) 483-490).
[0012] U.S. Pat. No. 4,623,704 describes a process utilizing a cellulose triacetate membrane for recovering ethylene from the reactor vent of a polyethylene plant. However, the vent stream that contained 96.5% ethylene is moderately upgraded to only 97.9% in the permeate stream for recycle to the reactor.
[0013] Membrane films of poly(2,6-dimethyl-1,4-phenylene oxide) exhibited pure gas propylene/propane selectivity of 9.1 (Ito and Hwang, Ibid.) Higher selectivity has been reported by Ilinitch et al. (J. Membrane Science 98 (1995) 287-290, J. Membrane Science 82 (1993) 149-155, and J. Membrane Science 66 (1992) 1-8), but the values at higher pressure were uncertain and were accompanied by undesirable plasticization of the membrane by propylene.
[0014] Polyimide membranes have been studied extensively for the separation of gases and to some degree for the separation of olefins from paraffins. Lee et al. (Kwang-Rae Lee and Sun-Tak Hwang, Separation of propylene and propane by polyimide hollow - fiber membrane module , J. Membrane Science 73 (1992) 37-45) disclose a hollow fiber membrane of a polyimide that exhibited mixed-gas propylene/propane selectivity in the range of 5-8 with low feed pressure (2-4 barg). The composition of the polyimide was not disclosed.
[0015] Krol et al. (J. J. Krol, M. Boerrigter, G. H. Koops, Polyimide hollow fiber gas separation membranes: preparation and the suppression of plasticization in propane/propylene environments , J. Membrane Science. 184 (2001) 275-286) report a hollow fiber membrane of a polyimide composed of biphenyitetracarboxylic dianhydride and diaminophenylindane which exhibited a pure-gas propylene/propane selectivity of 12; however, the membrane was undesirably plasticized by propylene at propylene pressure as low as 1 barg.
[0016] Polyimides based on 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (BFDA) and aromatic diamines have been found to provide a favorable combination of propylene permeability and propylene/propane selectivity. Permeation data for dense-film membranes of two different 6FDA-containing polyimides have been reported to have pure gas selectivity for propylene/propane in the range of 6-27. (C. Staudt-Bickel et al, Olefin/paraffin gas separations with 6 FDA - based polyimide membranes , J. Membrane Science 170 (2000) 205-214). Higher selectivity for similar 6FDA polyimides has been reported in U.S. Pat. No. 5,749,943 (Shimazu et al); however, it is anticipated that mixed-gas selectivity at high pressure will be much lower due to plasticization by the propylene-rich feed gas.
[0017] U.S. Pat. Nos. 4,532,041; 4,571,444; 4,606,903; 4,836,927; 5,133,867; 6,180,008; and 6,187,987 disclose membranes based on a polyimide copolymer derived from the co-condensation of benzophenone 3,3′,4,4′-tetracarboxylic acid dianhydride (BTDA) and a mixture of di(4-aminophenyl)methane and a mixture of toluene diamines useful for liquid separations.
[0018] U.S. Pat. Nos. 5,605,627; 5,683,584; and 5,762,798 disclose asymmetric, microporous membranes based on a polyimide copolymer derived from the co-condensation of benzophenone-3,3′,4,4′-tetracarboxylic acid dianhydride (BTDA) and a mixture of di(4-aminophenyl)methane and a mixture of toluene diamines useful for liquid filtration or dialysis membranes.
[0019] U.S. Pat. No. 5,635,067 discloses a fluid separation membrane based on blends of phenylindane-containing polyimide polymers with polyimides derived from the condensation of benzophenone-3,3′,4,4′-tetracarboxylic acid dianhydride (BTDA) with toluenediisocyanate (TDI) and 4,4′-methylene bisphenylisocyanate (MDI) and/or polyimides derived from the condensation of BTDA and pyromellitic dianhydride with TDI and MDI.
[0020] A significant shortcoming of published data for the separation of olefins from paraffins using membranes is the absence of data under practical industrial conditions: e.g., high feed and permeate pressure and high temperature. These are conditions under which plasticization of the membrane material could become significant and which could result in substantial decline in membrane performance over extended periods of time. In spite of the considerable efforts to provide industrially viable membranes for the separation of olefins from paraffins, none has proven to meet the performance criteria required for industrial application.
SUMMARY OF THE INVENTION
[0021] The invention is directed to a membrane separation process for separating an olefin from a mixture of olefins and paraffins comprising:
[0022] (a) providing a two-sided, selectively permeable membrane comprising a polymer or copolymer having repeating units of formula (I):
[0023] in which R 2 is a moiety of composition selected from the group of consisting of formula (A), formula (B), formula (C) and a mixture thereof,
[0024] Z is a moiety of composition selected from the group consisting of formula (L), formula (M), formula (N) and a mixture thereof; and
[0025] R 1 is a moiety of composition selected from the group consisting of formula (Q), formula (T), formula (S), and a mixture thereof,
[0026] (b) contacting one side of the membrane with a feed mixture comprising an olefin compound and a paraffin compound having a number of carbon atoms at least as great as the olefin compound,
[0027] (c) causing the feed mixture to selectively permeate through the membrane, thereby forming on the second side of the membrane an olefin-enriched permeate composition which has a concentration of the olefin compound greater than that of the feed mixture,
[0028] (d) removing from the second side of the membrane the olefin-enriched permeate composition, and
[0029] (e) withdrawing from the one side of the membrane an olefin-depleted composition.
DETAILED DESCRIPTION OF THE INVENTION
[0030] This invention is directed to a method of selectively separating olefinic hydrocarbons from paraffinic hydrocarbons using a membrane containing certain polyimide polymers, copolymers and blends thereof. The polymers which form these polyimides have repeating units as shown in the following formula (I):
[0031] in which R 2 is a moiety of composition selected from the group of consisting of formula (A), formula (B), formula (C) and a mixture thereof,
[0032] Z is a moiety of composition selected from the group consisting of formula (L), formula (M), formula (N) and a mixture thereof; and
[0033] R 1 is a moiety of composition selected from the group consisting of formula (Q), formula (T), formula (S), and a mixture thereof,
[0034] In a preferred embodiment the polyimide that forms the selective layer of the membrane has repeating units as shown in the following formula (II):
[0035] In this embodiment, moiety R 1 is of formula (Q) in 0-100% of the repeating units, of formula (T) in 0-100% of the repeating units, and of formula (S) in a complementary amount totaling 100% of the repeating units. A polymer of this structure is available from HP Polymer GmbH under the tradename P84 and is much preferred for use in the present invention. P84 is believed to have repeating units according to formula (II) in which R 1 is formula (Q) in about 16% of the repeating units, formula (T) in about 64% of the repeating units and formula (S) in about 20% of the repeating units. P84 is believed to be derived from the condensation reaction of benzophenone tetracarboxylic dianhydride (BTDA, 100 mole %) with a mixture of 2,4-toluene diisocyanate (2,4-TDI, 64 mole %), 2,6-toluene diisocyanate (2,6-TDI, 16 mole %) and 4,4′-methylene-bis(phenylisocyanate) (MDI, 20 mole %).
[0036] In another preferred embodiment, the polyimide that forms the selective layer has repeating units of compositions selected from among those shown in the following formulas (IIa and IIIb):
[0037] The repeating units can be exclusively of formula (IIIa) or formula (IIIb). Preferably, the repeating units are a mixture of formulas (IIIa) and (IIIb). In these embodiments, moiety R 1 is a composition of formula (Q) in about 1-99% of the repeating units, and of formula (T) in a complementary amount totaling 100% of the repeating units, and a is in the range of about 1-99% of the total of a and b.
[0038] A preferred polymer of this structure is available from HP Polymer GmbH under the tradename P84-HT325. P84-HT325 is believed to have repeating units according to formulas (IIIa and IIIb) in which the moiety R 1 is a composition of formula (Q) in about 20% of the repeating units and of formula (T) in about 80% of the repeating units, and in which a is about 40% of the total of a and b. P84-HT325 is believed to be derived from the condensation reaction of benzophenone tetracarboxylic dianhydride (BTDA, 60 mole %) and pyromellitic dianhydride (PMDA, 40 mole %) with 2,4-toluene diisocyanate (2,4-TDI, 80 mole %) and 2,6-toluene diisocyanate (2,6-TDI, 20 mole %).
[0039] In yet another preferred embodiment, the selectively permeable portion of the membrane can be formed of a material comprising a blend of the above mentioned polymers. For example, it is contemplated that a membrane can be formed from a blend comprising a first polymer having repeating units of formula (IIIa), formula (IIIb) as defined above, or a mixture of formulas (IIIa) and (IIIb) and a second polymer having repeating units of formula (II) as defined above. Greater preference is given to a membrane of a blend consisting essentially of the first and second polymers. In such preferred composition, the second polymer should constitute about 10-90 wt. % of the total of the first polymer and the second polymer.
[0040] The polyimides should be of suitable molecular weight to be film forming and pliable so as to be capable of being formed into continuous films or membranes. The polyimides of this invention preferably have a weight average molecular weight within the range of about 20,000 to about 400,000 and more preferably about 50,000 to about 300,000. The polymer can be formed into films or membranes by any of the diverse techniques known in the art. The polymers are usually glassy and rigid, and therefore, may be used to form a single-layer membrane of an unsupported film or fiber of the polymer. Such single-layer films are normally too thick to yield commercially acceptable transmembrane flux of the preferentially permeable component of the feed mixture. To be more economically practical, the separation membrane can comprise a very thin selective layer that forms part of a thicker structure. This structure may be, for example, an asymmetric membrane, which comprises a thin, dense skin of selectively permeable polymer and a thicker micro-porous support layer which is adjacent to and integrated with the skin. Such membranes are described, for example, in U.S. Pat. No. 5,015,270 to Ekiner.
[0041] In a preferred embodiment, the membrane can be a composite membrane, that is, a membrane having multiple layers of typically different compositions. Modem composite membranes typically comprise a porous and non-selective support layer. It primarily provides mechanical strength to the composite. A selective layer of another material that is selectively permeable, is placed coextensively on the support layer. The selective layer is primarily responsible for the separation properties. Typically, the support layer of such a composite membrane is made by solution-casting a film or spinning a hollow fiber. Then the selective layer is usually solution coated on the support in a separate step. Alternatively, hollow-fiber composite membranes can be made by co-extrusion of both the support material and the separating layer simultaneously as described in U.S. Pat. No. 5,085,676 to Ekiner.
[0042] The membranes of the invention may be housed in any convenient type of separation unit. For example, flat-sheet membranes can be stacked in plate-and-frame modules or wound in spiral-wound modules. Hollow-fiber membranes are typically potted with a thermoset resin in cylindrical housings. The final membrane separation unit can comprise one or more membrane modules. These can be housed individually in pressure vessels or multiple modules can be mounted together in a common housing of appropriate diameter and length.
[0043] In operation, a mixture of one or more olefin compounds and one or more paraffin compounds is contacted with one side of the membrane. Under a suitable driving force for permeation, such as imposing a pressure difference between the feed and permeate sides of the membrane, the olefin compounds pass to the permeate side at higher rate than the paraffin compounds of the same number of carbon atoms. That is, a three carbon olefin permeates faster than a three carbon paraffin. This produces an olefin-enriched stream which is withdrawn from the permeate side of the membrane. The olefin-depleted residue, occasionally referred to as the “retentate”, is withdrawn from the feed side.
[0044] The novel process can operate under a wide range of conditions and is thus adapted to accept a feed stream supplied from diverse sources. If the feed stream is a gas that exists already at a sufficiently high, above-atmospheric pressure and a pressure gradient is maintained across the membrane, the driving force for separation can be adequate without raising feed stream pressure farther. Otherwise, the feed stream can be compressed to a higher pressure and/or a vacuum can be drawn on the permeate side of the membrane to provide adequate driving force. Preferably the driving force for separation should be a pressure gradient across the membrane of about 0.7 to about 11.2 MPa (100-1600 psi).
[0045] The novel process can accept a feed stream in either the gaseous state or the liquid state. The state of matter will depend on the composition and on the pressure and temperature of the olefin/paraffin feed stream. When the feed stream is in the liquid state, the separation can be carried out by the pervaporation mechanism. Basically, in pervaporation, components of the liquid feed mixture in contact with the membrane permeate and evaporate through the membrane, thereby separating the component in the vapor phase.
[0046] This invention is particularly useful for separating propylene from propylene/propane mixtures. Such mixtures are produced as effluent streams of olefin manufacturing operations, and in various process streams of petrochemical plants, for example. Thus in a preferred embodiment, the process involves passing a stream comprising propylene and propane in contact with the feed side of a membrane that is selectively permeable with respect to propylene and propane. The propylene is concentrated in the permeate stream and the retentate stream is thus correspondingly depleted of propylene. The membranes of this invention exhibit unexpectedly high propylene/propane selectivity which distinguishes them from prior art membranes. Furthermore, the membranes of this invention exhibit stable performance over long periods of time under conditions where membranes of the prior art degrade significantly in performance.
[0047] The fundamental steps of the separation process include contacting one side of the membrane with a feed mixture comprising an olefin compound and a paraffin compound having a number of carbon atoms at least as great as the olefin compound,
[0048] causing the feed mixture to selectively permeate through the membrane, thereby forming on the second side of the membrane an olefin-enriched permeate composition which has a concentration of the olefin compound greater than that of the feed mixture,
[0049] removing from the second side of the membrane the olefin-enriched permeate composition, and
[0050] withdrawing from the one side of the membrane an olefin-depleted composition which has a concentration of the olefin compound less than that of the feed mixture.
[0051] This invention is now illustrated by examples of certain representative embodiments thereof, wherein all parts, proportions and percentages are by weight unless otherwise indicated. All units of weight and measure not originally obtained in SI units have been converted to SI units. The entire disclosures of U.S. patents named in the following examples are hereby incorporated by reference herein.
EXAMPLES
Example 1
Propylene/Propane Gas Separation with P84 Membrane
[0052] Asymmetric hollow-fiber membrane of P84 was spun from a solution of 32% P84, 9.6% tetramethylenesulfone and 1.6% acetic anhydride in N-methylpyrrolidinone (NMP) with methods and equipment as described in U.S. Pat. Nos. 5,034,024 and 5,015,270. The nascent filament was extruded at a rate of 180 cm 3 /hr through a spinneret with fiber channel dimensions of outer diameter 559 μm and inner diameter equal to 254 μm at 75° C. A fluid containing 85% NMP in water was injected into the bore of the fiber at a rate of 33 cm 3 /hr. The nascent fiber traveled through an air gap of 5 cm at room temperature into a water coagulant bath at 24° C. and the fiber was wound up at a rate of 52 m/min.
[0053] The water-wet fiber was washed with running water at 50° C. to remove residual solvent for about 12 hours and then sequentially exchanged with methanol and hexane as taught in U.S. Pat. Nos. 4,080,744 and 4,120,098, followed by vacuum drying at room temperature for 30 minutes. After that the fibers were dried at 100° C. for one hour. Samples of fiber were formed into four test membrane modules of 52 fibers each. The fiber in the modules was treated to seal defects in the separating layer with a method similar to the method described in U.S. Pat. No. 4,230,463. The fiber was thus contacted with a solution of 2% wt. 1-2577 Low-VOC Conformal Coating (Dow Corning Corporation) in 2,2,4-trimethylpentane for 30 minutes and then dried.
[0054] The modules were measured in permeation of a feed of mixed propylene/propane (50:50 mole %). The feed mixture was provided in the vapor state by controlling the feed pressure at 2.8 MPa (400 psig) and the feed temperature at 90° C. The feed mixture was supplied to contact the outside of the fibers and the permeate stream was collected at atmospheric pressure. The permeate flowrate was measured by volumetric displacement with bubble flowmeters. The feed flowrate was maintained at greater than twenty times the permeate flowrate. This rate was high enough that the composition on the feed side remained roughly constant while the feed mixture permeated the membrane. This was done to simplify calculation of the membrane permeation performance. The composition of the permeate stream was measured by gas chromatography with a flame ionization detector. The average permeate composition was 92.2% propylene and 7.8% propane.
[0055] The performance of the membrane was expressed in terms of propylene permeance and propylene/propane selectivity. The permeance is the flowrate of propylene across the membrane normalized by the membrane surface area and the propylene partial pressure difference across the membrane. It is reported in gas permeation units (“GPU”). One GPU equals 10 −6 cm 3 (at standard temperature and pressure “STP”)/(sec·cm 2 ·cmHg). The propylene/propane selectivity is the ratio of the permeance of propylene divided by the permeance of propane. The performance of the four modules is shown in Table 1.
TABLE I Propylene Permeance (1) Propylene/Propane GPU selectivity (1) 1.3 12.0 0.97 12.5 1.4 12.9 1.3 13.1
Example 2
Propylene/Propane Gas Separation with P84 Non-Posttreated Membrane
[0056] A sample of the fiber from Example 1 was processed and formed into a test module as in Example 1 except that the fiber was not treated to seal defects in the separating layer. The propylene permeance was 1.7 GPU and the propylene/propane selectivity was 7.5. Although the selectivity was lower than the selectivity of the treated fiber of Example 1, it was high enough to suggest that the P84 fiber with acceptable performance characteristics can be produced as an asymmetric membrane without the sealing posttreatment.
Example 3
Propylene/Propane Gas Separation with P84 Membrane
[0057] Asymmetric hollow-fiber membrane of P84 was prepared as in Example 1 with the following two changes: (a) the water-bath temperature was lowered to 8° C. and (b) the spinneret temperature was increased to 87° C. The fiber was washed, dried and built into test modules and tested in permeation of a 50:50 mole % mixed propylene/propane feed mixture as in Example 1. The propylene permeance was 0.61 GPU and the propylene/propane selectivity was 15.
Example 4
Durability of P84 Membrane in Propylene/Propane Gas Separation with P84 Membrane
[0058] Asymmetric hollow-fiber membrane of P84 similar to the fiber of Example 3 was tested for duration of 4 days at 90° C. with a 50:50 mole % feed mixture of propylene/propane at 2.8 MPa (400 psig). The test was designed to simulate commercial operating conditions. Results are shown in Table II. No decline in selectivity was observed. A slight decline was observed in propylene permeance, which stabilized after the second day.
TABLE II Feed Propylene/ Pressure Propane Propylene permeance Time MPa (psig) Selectivity GPU 4 hours 1.7 (250) 13 0.76 1 day 1.7 (250) 13 0.96 2 days 1.7 (250) 13 0.73 3 days 2.8 (400) 12 0.61 4 days 2.8 (400) 14 0.61
Example 5
Propylene/Propane Liquid Feed Separation with P84 Membrane
[0059] One of the modules of Example 1 was tested using a 50:50 mole % feed mixture of propylene/propane. Feed pressure and temperature were controlled at 2.8 MPa (400 psig) and 50° C., respectively, to place the feed mixture in the liquid state. The permeate was withdrawn at atmospheric pressure, therefore the permeate was in the vapor phase. For this type of separation the concentration difference across the membrane is usually considered to be the driving force for separation instead of the partial pressure difference as used in gas or vapor permeation. For comparison of the results of this Example with permeation under vapor state feed conditions, the simplifying mathematical treatment described in J. G. Wijmans and R. W. Baker, A simple predictive treatment of the permeation process in pervaporation , J. Membrane Science 79 (1993) 101-113) was applied. Such analysis assumes that the liquid feed evaporates to produce a saturated vapor phase on the feed side of the membrane and then permeates through the membrane driven by a partial pressure gradient. This analysis provides a mathematical model that includes terms for feed-side and permeate-side vapor pressures and permeance and selectivity comparable to those used in the separation of gaseous state feed mixtures. The model also contains a term related to the liquid-vapor equilibrium. With the feed mixture of 50:50 mole % propylene/propane in the liquid state, the membrane produced a permeate stream of 93% propylene. By application of the model, it was determined that the propylene permeance was 0.46 GPU and the propylene/propane selectivity was 16. In separate testing with feed mixture of the same composition in the vapor state at 2.8 MPa (400 psig) and 90° C., the propylene permeance was 0.95 GPU and the propylene/propane selectivity was 13. This shows that the membrane of P84 can be useful for separation service for liquid propylene/propane.
Example 6
Propylene/Propane Gas Separation with a Membrane of P84 Blended with P84-HT325
[0060] Asymmetric hollow-fiber membrane of a 1:1 blend of P84 and P84-HT325 was spun from a solution of 16% P84, 16% P84-HT325, 9.6% tetramethylene sulfone and 1.6% acetic anhydride in NMP by the process described in Example 1. The spinning conditions and equipment were similar except that the spinneret temperature was 85° C., the bath temperature was 8° C. and the air gap was 10 cm. The fiber was formed into a module which was tested for permeation of a propylene/propane (50:50 mole %) feed mixture as in Example 1. The permeation performance was 1.9 GPU propylene permeance and 11.9 propylene/propane selectivity.
Example 7
Propylene/Propane Liquid Feed Separation with a Membrane of P84 blended with P84-HT325
[0061] The module of 1:1 blend of P84 and P84-HT325 of Example 6 was tested with 50:50 mole % feed mixture of propylene/propane. The feed mixture was maintained in the liquid state by applying the conditions described in Example 5, i.e., the feed pressure was 2.8 MPa (400 psig) and the temperature was 50° C. The permeate was withdrawn as a vapor at atmospheric pressure.
[0062] The membrane produced a permeate with 93.6% propylene; the propylene permeance was 0.6 GPU and the propylene/propane selectivity was 15.5. This shows that the membrane of 1:1 blend of P84 and P84-HT325 can provide useful separation with liquid propylene/propane feed.
Example 8
Propylene/Propane Liquid Feed Separation with a Membrane of P84 blended with P84-HT325
[0063] The test in Example 7 (i.e., with membrane of 1:1 blend of P84 and P84-HT325) was continued for a duration of 100 hours, to assess membrane performance stability under simulated commercial conditions. Results are shown in Table III. No significant decline was observed.
TABLE III Propylene Time Propylene/Propane Permeance Hours Selectivity GPU 24 15.5 0.56 GPU 60 15.9 0.59 GPU 84 15.6 0.67 GPU 110 15.8 0.67 GPU
Example 9
Propylene/Propane Gas Separation with P84 Dense Film Membrane
[0064] A thin dense film of P84 polymer was cast from a solution comprising 20% P84 in NMP. The film was dried at 200° C. in a vacuum oven for four days. A sample of the polymer film was tested in a modified 47-mm ultrafiltration style permeation cell (Millipore), using a feed mixture of 50:50 mole % propylene/propane at 2.8 MPa (400 psig) pressure and 90° C. temperature. The permeate pressure was 2-5 mm Hg. The feed flowrate was high enough to ensure low conversion of the feed into permeate so that the composition on the feed side was constant. The compositions of the feed and permeate streams were measured by gas chromatography with a flame ionization detector. The permeate flowrate was determined from the increase in pressure over time in the fixed-volume permeate chamber of the permeation cell.
[0065] The permeation performance of the polymer is characterized by the two parameters: propylene permeability and propylene/propane permselectivity. The permeability is the flowrate of propylene across the film normalized by the film surface area and film thickness and by the propylene partial pressure difference across the film. Units of permeability are Barrers. One Barrer equals 10 −10 cm 3 (STP)·cm/(sec·cm 2 ·cm Hg). The propylene/propane permselectivity is the ratio of the propylene and propane permeabilities. The propylene permeability of the P84 film at 90° C. and 2.8 MPa (400 psig) was 0.24 Barrers; and the propylene/propane permselectivity was 15.5. The permselectivity was in good agreement with the selectivity measured with hollow-fiber membranes of P84 polymer.
Example 10
Propylene/Propane Separation with a Membrane of TDI+BTDA:BPDA(1:1)
[0066] A dense film of a copolymer of toluenediisocyanate (TDI, a mixture of 20% 2,6-toluenediisocyanate and 80% 2,4-toluenediisocyanate) and a 1:1 mixture of benzophenone-3,3′,4,4′-tetracarboxylic acid dianhydride (BTDA) with 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (BPDA) was tested in permeation with 50:50 mole % mixed propylene/propane feed at 2.8 MPa (400 psig) and 90° C. as in Example 9. The propylene permeability of the film was 0.48 Barrers and the propylene/propane permselectivity was over 16.
Comparative Example 1
Polypropylene/Propane Separation with a Traditional Composition Fiber Membrane
[0067] Samples of composite hollow-fiber membrane of Matrimid® 5218 a copolymer of 5,x-amino-(4-aminophenyl)-1,1,3 trimethyl indane and 3,3′,4,4′-benzophenone tetracarboxylicdianhydride (Vantico, Inc.) were tested in permeation over a 72-hour period with a feed mixture of 50:50 mole % propylene/propane at 1.7 MPa (250 psig) and 90° C. as in Example 1. The purpose of the test was to determine the membrane performance stability under simulated commercial conditions. This membrane, described in U.S. Pat. No. 5,468,430 is a commercial gas-separation membrane produced by MEDAL, LP. Results of the test are shown in Table IV.
TABLE IV Time Propylene/Propane Propylene permeance hours Selectivity GPU 2 5.5 9.0 24 7.0 4.8 48 7.1 4.0 72 7.2 3.8
[0068] As apparent from these results, the membrane exhibited low selectivity and lost greater than 50% of its initial permeance during the test, unlike the membranes of this invention.
Comparative Example 2
Propylene/Propane Separation with a Polyaramid Membrane
[0069] Samples of asymmetric hollow-fiber membrane made from a blend of two aromatic polyamides were tested in permeation of a feed mixture of 50:50 mole % propylene/propane at 2.8 MPa (400 psig) and 90° C. as in Example 1. This membrane is described in U.S. Pat. No. 5,085,774 (Example 15). The fiber was spun at a draw ratio of 7.3. It is an established gas-separation membrane applied in the separation of hydrogen from mixtures with hydrocarbons or carbon monoxide. It exhibited a propylene permeance of 0.23 GPU and a propylene/propane selectivity of 9.5. This performance was less than that of the novel membranes having composition of formula (I). This result was unexpected because the membrane of aromatic polyamide has very high selectivity in separations of other mixtures, for example a selectivity of higher than 200 for H 2 /CH 4 at 90° C.
[0070] Although specific forms of the invention have been selected for illustration in the preceding description which is drawn in specific terms for the purpose of describing these forms of the invention fully and amply for one of average skill in the pertinent art, it should be understood that various substitutions and modifications which bring about substantially equivalent or superior results and/or performance are deemed to be within the scope and spirit of the following claims. | A process for the separation or concentration of olefinic hydrocarbons from mixtures of olefinic and paraffinic hydrocarbons uses a polyimide membrane. The process is well suited to separating propylene from propylene/propane mixtures. The novel method The membrane exhibits good resistance to plasticization by hydrocarbon components in the gas mixture under practical industrial process conditions. | 2 |
TECHNICAL FIELD
[0001] This disclosure relates to an instrument for capturing free thrombi.
BACKGROUND
[0002] In recent years, treatment of aortic diseases employs percutaneous procedures such as insertion/placement of various instruments including artificial blood vessels and stents in the lesion through a catheter introduced into a human body from a site of incision of an arterial vessel. However, in such percutaneous procedures, there is a risk of releasing of a thrombus from a fragile inner wall of a blood vessel in the lesion to cause clogging of a narrow blood vessel in the distal side, leading to necrosis of a tissue downstream thereof. In particular, clogging of the carotid artery extending to the head with a thrombus may threaten a patient's life.
[0003] To avoid such a risk, an instrument for capturing free thrombi for capturing thrombi released from a blood vessel, which instrument is transiently placed in the distal side rather than the lesion in which an instrument such as an artificial blood vessel is to be placed, is being developed (JP 4073869 B). The instrument for capturing free thrombi comprises a filter section composed of a mesh material or the like to capture the released thrombi.
[0004] The blood coagulation reaction involved in the formation of a thrombus is a very complex reaction in which various blood coagulation factors are involved, and it has been considered that the stage of primary hemostasis, in which platelets are involved, and the stage of coagulation thrombus formation, in which blood coagulation factors such as thrombin are involved to stabilize and strengthen fibrin, are especially important. No specific compound has been developed that can inhibit the blood coagulation reaction in both the stage of primary hemostasis, in which platelets are involved, and the stage of coagulation thrombus formation, in which blood coagulation factors are involved.
[0005] Although the blood coagulation reaction is indispensable in achieving hemostasis upon bleeding caused by injury or the like, there is a danger that contacting of blood with an instrument such as an artificial blood vessel in a percutaneous procedure using the instrument may promote the blood coagulation reaction, causing inhibition of blood flow by formation of a blood clot or coagulation thrombus.
[0006] However, at present, since the size of the pores in the filter section of the instrument for capturing free thrombi needs to be as small as possible to securely capture free thrombi, blood flow is disturbed to cause congestion, which then promotes the blood coagulation reaction and again causes disturbance of blood flow, resulting in a vicious circle. Because of such a background, even with continuous administration of an anticoagulant to the blood of the patient, the available time of a conventional instrument for capturing free thrombi has been very limited. There is an instrument for capturing free thrombi whose surfaces are coated with an anticoagulant, heparin (Spider FX; ev3), but even this instrument can be used for only not more than 1 hour. Therefore, a percutaneous procedure using an instrument such as an artificial blood vessel needs to be finished within a short period of time, and the burden of the physician who performs the percutaneous procedure is extremely heavy. Thus, a completely novel method is demanded for extending the available time of an instrument for capturing free thrombi.
[0007] In view of this there is a need to provide an instrument for capturing free thrombi that inhibits the blood coagulation reaction at the stage of primary hemostasis, in which platelets are involved, and at the stage of coagulation thrombus formation, in which blood coagulation factors are involved, thereby securely capturing free thrombi and extending the available time of the instrument.
SUMMARY
[0008] We discovered that an instrument for capturing free thrombi comprising a compound having an antithrombin activity immobilized on a surface(s) thereof exhibits a remarkable anticoagulant action, and that the compound having an antithrombin activity is strongly immobilized on the surface(s) of the instrument for capturing free thrombi.
[0009] That is, we provide an instrument for capturing free thrombi, comprising a compound having an antithrombin activity immobilized on a surface(s) thereof. Further, we provide the above-described instrument for use in capturing free thrombi. Further, we provide a method of capturing free thrombi, the method comprising capturing free thrombi in blood in a living body using the instrument.
[0010] The compound having an antithrombin activity is preferably immobilized on the surface(s) of the instrument for capturing free thrombi as a conjugate with a macromolecular compound, preferably a macromolecular compound mainly constituted by units derived from at least one type of monomers selected from the group consisting of ethylene glycol, vinyl acetate, vinyl pyrrolidone, propylene glycol, vinyl alcohol and siloxane. That is, the instrument for capturing free thrombi is preferably an instrument for capturing free thrombi comprising a conjugate immobilized on the surface(s), which conjugate is formed between the compound having an antithrombin activity and a macromolecular compound, preferably a compound mainly constituted by units derived from at least one type of monomers selected from the group consisting of ethylene glycol, vinyl acetate, vinyl pyrrolidone, propylene glycol, vinyl alcohol and siloxane.
[0011] The compound having an antithrombin activity is preferably a compound represented by Formula (I) below:
[0000]
[0000] wherein R 1 represents a (2R,4R)-4-alkyl-2-carboxypiperidino group, and R 2 represents a phenyl group or a fused polycyclic compound residue, which fused polycyclic compound residue is optionally substituted by a lower alkyl group(s) and/or lower alkoxy group(s), and/or by an amino group(s) substituted by a lower alkyl group(s).
[0012] The macromolecular compound is preferably one or more types of compounds selected from the group consisting of polyether-modified silicones, vinyl acetate-vinyl pyrrolidone copolymers and partially saponified polyvinyl alcohols. The macromolecular compound is especially preferably an amino-polyether-modified silicone.
[0013] The compound represented by Formula (I) is preferably (2R,4R)-4-methyl-1-((2S)-2-{[(3RS)-3-methyl-1,2,3,4-tetrahydroquinolin-8-yl]sulfonyl}amino-5-guanidinopentanoyl)piperidine-2-carboxylic acid.
[0014] The instrument for capturing free thrombi preferably comprises a bag-shaped filter section, more preferably comprises: a ring-shaped section; a core section penetrating the ring-shaped section; a bag-shaped filter section whose open end is attached to the ring-shaped section and whose closed end is attached to a part of the distal side of the core section; and a support wire section arranged between the core section and the ring-shaped section.
[0015] The material of the filter section is preferably one or more types of compounds selected from the group consisting of polyesters, polyalkyl(meth)acrylates, polyurethanes, polyvinyl chloride and polycarbonate, and the material is especially preferably polyethylene terephthalate.
[0016] We can thus provide an instrument for capturing free thrombi comprising a compound that remarkably inhibits the blood coagulation reaction at the stage of primary hemostasis, in which platelets are involved, and at the stage of coagulation thrombus formation, in which blood coagulation factors are involved, which compound is strongly immobilized on the surface(s) of the instrument while maintaining its anticoagulant activity. Further, the instrument for capturing free thrombi enables secure capturing of free thrombi and remarkable extension of the available time of the instrument, thereby reducing the burden of the physician who performs a percutaneous procedure using an instrument such as an artificial blood vessel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a diagram showing the relative ratio of platelets attached to each prepared polyethylene terephthalate mesh.
[0018] FIG. 2 is a schematic view showing the spread state of an example of the instrument for capturing free thrombi.
[0019] FIG. 3 is a schematic view showing the folding process of an example of the instrument for capturing free thrombi.
[0020] FIG. 4 is a schematic view showing the folded state of an example of the instrument for capturing free thrombi.
DESCRIPTION OF SYMBOLS
[0000]
1 Instrument for capturing free thrombi
11 Core section
12 Ring-shaped section
13 Filter section
14 Support wire section
DETAILED DESCRIPTION
[0026] The terms used in this description are as defined below unless otherwise specified.
[0027] The term “instrument for capturing free thrombi” means a medical instrument also called a filter instrument, and comprises a filter section composed of a mesh material and/or the like for capturing free thrombi.
[0028] Examples of the filter section of the instrument for capturing free thrombi include a filter section prepared by forming a sheet having a large number of pores into a bag shape, and a filter section prepared by forming a sheet, interweaved with fibers in the form of a mesh or net, into a bag shape.
[0029] Examples of the material of the filter section include polymer materials, for example, polyesters such as polyethylene terephthalate (hereinafter referred to as “PET”); polytetrafluoroethylene; cellulose; cellulose acetate; polycarbonate; polysulfone (hereinafter referred to as “PSf”); polyether sulfone; polyalkyl (meth)acrylates (the alkyl moiety is preferably C 1 -C 4 lower alkyl, especially preferably methyl) such as polymethyl methacrylate (hereinafter referred to as “PMMA”); polyamides; polyvinylidene fluoride; polyvinyl chloride; polyacrylonitrile; polyurethanes; polystyrene; polyethylene; polypropylene; polymethylpentene; and polyimides. Among these, polyesters, polyalkyl(meth)acrylates, polyurethanes, polyvinyl chloride, polycarbonate and polytetrafluoroethylene are preferred, and, because of its high flexibility and in vivo stability, polyesters, especially PET, are more preferred. These materials may be used individually, or two or more of these materials may be used in combination.
[0030] In cases where the filter section is composed of an organic fiber prepared with the above-described polymer materials, the filter section has a fiber diameter of preferably not more than 40 μm, more preferably not more than 35 μm, still more preferably not more than 30 μm, in order to obtain a thinner filter section and to allow easy folding of the filter section. The lower limit of the fiber diameter is not limited, and, from the viewpoint of strength, the fiber diameter is usually not less than 20 μm.
[0031] The organic fiber constituting the filter section may be either a monofilament or a multifilament, and is preferably a monofilament since it is smoother and less likely to activate the blood coagulation reaction.
[0032] The material of the filter section may also be a metal such as stainless steel or a nickel-titanium alloy in view of the durability and the shape retention property. In cases where a metal is used as the material of the filter section, the conjugate that remarkably inhibits the blood coagulation reaction can be strongly immobilized by, for example, using a coupling agent that can be adsorbed or bound to the metal, or coating the surfaces of the metal with the polymer material.
[0033] More specific examples of the constitution of the instrument for capturing free thrombi include:
[0000] a constitution in which a flexible wire is bent into a loop shape and both ends of the wire is bundled and fixed on a delivery wire, wherein the open end of a bag-shaped filter section is attached to the ring-shaped wire;
a constitution in which a plurality of flexible wires are shaped into a spindle, and both ends of the wires are fixed at two positions on a delivery wire in the longitudinal direction, wherein the open end of a bag-shaped filter section is attached in the middle of the wires in the longitudinal direction and the closed distal end of the bag-shaped section is attached to the distal ends of the wires; and
a constitution as shown in FIGS. 2 to 4 , comprising: a ring-shaped section 12 composed of a flexible wire material that can be freely bent and has elastic recoverability, which ring-shaped section 12 has a nearly circular shape; a core section 11 that penetrates the ring-shaped section 12 , wherein the shape of the core section 11 is linear and can be flexibly changed; a filter section 13 whose open end is attached in its entirety to the ring-shaped section 12 and whose closed end is attached to a part of the distal end side of the core section 11 , which filter section 13 is porous and bag-shaped; and a plurality of support wire sections 14 composed of linear members whose shapes can be flexibly changed, which support wire sections 14 are arranged between a part of the core section 11 proximal to the closed end of the filter section 13 and the ring-shaped section 12 ; wherein the state of the ring-shaped section 12 changes from a folded state where the ring-shaped section 12 is folded such that a plurality of mountains facing the distal end side of the core section 11 and a plurality of valleys facing the proximal end side of the core section 11 alternately occur and the mountains and valleys are positioned close to each other, to a spread state where the ring-shaped section 12 is spread into a nearly circular shape due to the elastic recoverability of the ring-shaped section itself, and the state of the ring-shaped section 12 also changes from the spread state to the folded state due to tensions of the support wire sections 11 exerted by application of an external force to the support wire sections 14 in the direction that causes bundling of the support wire sections 14 with the core section 11 (JP 4073869 B; the instrument 1 for capturing free thrombi, having this constitution, is hereinafter referred to as the “filter instrument A”).
[0034] With a constitution such as that of the filter instrument A, the spread ring-shaped section 12 is supported by the support wire sections 14 so that the direction of the central axis can be easily adjusted nearly to the direction of blood flow. Therefore, even with a simple structure, free thrombi can be stably and securely captured into the filter section 13 without missing it to the distal side. Further, when the ring-shaped section 12 comes into contact with the inner wall of a blood vessel, the elasticity of the ring-shaped section 12 allows appropriate bending of the ring-shaped section 12 following contraction of the blood vessel so that free thrombi can be stably and securely captured into the filter section 13 without missing the free thrombi to the distal side. Further, when an external force is directly applied to the ring-shaped section 12 or when the support wire sections 14 are brought close to the core section 11 by an external force while the support wire sections 14 are kept tense, the open end of the ring-shaped section 12 is made narrower and compactly folded so that the filter instrument A can be appropriately delivered in such a folded state to a predetermined site in a blood vessel by insertion of the instrument into a catheter or the like, while the filter instrument A in the state where thrombi are captured in the filter section 13 can be recovered, without missing the thrombi, by folding the ring-shaped section 12 and thereby narrowing the open end.
[0035] Examples of the core section 11 of the filter instrument A include thin, flexible wires made of stainless steel or a nickel-titanium alloy, which is excellent in the elastic recoverability. In such a case, the core section 11 may be constituted of a plurality of wires joined together, but the core section 11 is preferably constituted by a single wire.
[0036] Examples of the ring-shaped section 12 of the filter instrument A include a wire that is composed of the same material as the core section 11 and formed into a circular ring shape having a diameter of about 4 to 12 mm.
[0037] Examples of the filter section 13 of the filter instrument A include those prepared by forming a flexible, firm, triangular and porous sheet into the form of a conical bag. The size of each pore provided in the filter section 13 is preferably 70 to 200 μm, and, in view of increasing the accuracy of capturing free thrombi while suppressing the blood coagulation reaction, the sizes of the pores are more preferably uniform. More specifically, the sizes of the pores are preferably within the range of the mean value±20%.
[0038] The ratio of the area of the pores provided per unit area of the filter section, the pore ratio, is preferably not less than 30%, more preferably not less than 40%, still more preferably not less than 50%, in view of reducing inhibition of blood flow. The pore ratio is, of course, less than 100%, and, in view of the strength, the pore ratio is usually not more than 90%.
[0039] Examples of the support wire section 14 of the filter instrument A include wires made of an appropriate material having high strength, whose tension can be increased by the action of an external force, such as metallic wires, and threads and wires made of polymer materials, that may be the same as, or different from, the material of the core section 11 .
[0040] The term “compound having an antithrombin activity” means a compound having a high binding affinity to thrombin.
[0041] The compound having an antithrombin activity is preferably the “compound represented by Formula (I),” wherein R 1 represents a (2R,4R)-4-alkyl-2-carboxypiperidino group (the alkyl is preferably lower alkyl), and R 2 represents a phenyl group or a fused polycyclic compound residue, which fused polycyclic compound residue is optionally substituted by a lower alkyl group(s) and/or lower alkoxy group(s), and/or by an amino group(s) substituted by a lower alkyl group(s); the lower alkyl is C 1 -C 4 alkyl described above that is a compound comprising a compound comprising a guanidino structure, more preferably (2R,4R)-4-methyl-1-((2S)-2-{[(3RS)-3-methyl-1,2,3,4-tetrahydroquinolin-8-yl]sulfonyl}amino-5-guanidinopentanoyl)piperidine-2-carboxylic acid (hereinafter referred to as “argatroban”). Argatroban is a pharmaceutical compound synthesized in 1978 having selective antithrombin activity of an arginine derivative. Since argatroban is commercially available as an antithrombotic drug, a commercially available product may be used. The term “having the selective antithrombin activity” herein means to have a high binding affinity to thrombin. Examples of the index for evaluating the antithrombin activity of a compound include the inhibition constant (hereinafter referred to as “Ki”) calculated from the Lineweaver-Burk plot based on the absorbance of the test solution. A lower Ki indicates higher binding affinity to thrombin, that is, higher antithrombin activity. Ki is preferably not more than 10 μM, more preferably not more than 1 μM, still more preferably not more than 500 nM. A single compound having an antithrombin activity may be used, or two or more compounds having an antithrombin activity may be used in combination.
[0042] The compound having an antithrombin activity is preferably immobilized on the surface(s) of the instrument for capturing free thrombi as a conjugate with a macromolecular compound mainly constituted by units derived from at least one type of monomers selected from the group consisting of ethylene glycol, vinyl acetate, vinyl pyrrolidone, propylene glycol, vinyl alcohol and siloxane. The “conjugate” formed by binding of the compound having an antithrombin activity with the macromolecular compound is preferably hydrophilic in cases where its aqueous solution is prepared. The term “mainly constituted” means that not less than 90 mol %, preferably not less than 95 mol %, still more preferably not less than 98 mol % of the total constitution units (repeating units) constituting the macromolecular compound are constituted by the above-described units, and that a unit(s) other than the above-described units may be contained at a content of not more than 10 mol %, preferably not more than 5 mol %, more preferably not more than 2 mol %, as long as the unit(s) do/does not adversely affect the desired effect. The macromolecular compound is more preferably a copolymer of monomers selected from the group consisting of ethylene glycol, vinyl acetate, vinyl pyrrolidone, propylene glycol, vinyl alcohol and siloxane, especially preferably a copolymer of at least two types of monomers selected from these monomers. The molecular weight of the macromolecular compound is not limited, and usually about 5,000 to 2,000,000, preferably 10,000 to 1,500,000, in terms of the weight average molecular weight.
[0043] The term “hydrophilicity” means that a compound is soluble in water, or, even in cases where a compound is insoluble in water, the compound interacts with water molecules by electrostatic interactions and/or hydrogen bonds.
[0044] Preferred examples of the macromolecular compound that is bound to the compound having an antithrombin activity to constitute the above-described conjugate, especially the “copolymer of monomers selected from the group consisting of ethylene glycol, vinyl acetate, vinyl pyrrolidone, propylene glycol, vinyl alcohol and siloxane” (hereinafter referred to as an “anti-platelet adhesion copolymer”), include: polyvinyl alcohol; polyvinyl pyrrolidone; polyethylene glycol; polypropylene glycol; and macromolecular compounds composed of polyether and polysiloxane; and copolymers and graft polymers of monomers of these macromolecular compounds and other monomers. The macromolecular compound is preferably a macromolecular compound composed of polyether and polysiloxane, partially saponified polyvinyl alcohol, or a copolymer of vinyl pyrrolidone and vinyl acetate, having high hydrophilicity. Since these are commercially available, a commercially available product may be used. The commercially available products used in the Examples below are examples of the macromolecular compound that can be used in our instruments and methods. These may be used individually, or two or more of these may be used in combination.
[0045] Examples of the “macromolecular compound composed of polyether and polysiloxane” include copolymers, polymer complexes and polymer blends of polyether and polysiloxane. The copolymer of polyether and polysiloxane is composed of a polyether unit(s) and a polysiloxane unit(s), and the form of the copolymer may be any of a random copolymer, block copolymer and graft copolymer. A polyether-modified silicone is especially preferred since it has high hydrophilicity.
[0046] Examples of the “polyether” include structures derived from polyethylene oxide or polypropylene oxide. The “polyether” herein means a structure represented by Formula (II) (wherein R 3 represents an alkyl group having not more than 6 carbon atoms), and the “structure derived from polypropylene glycol” as an example of the polyether means a structure represented by Formula (III).
[0000]
[0047] The “polyether-modified silicone” means a silicone comprising a polyether unit bound to a side chain of the silicone chain, and may be a polyether-modified silicone that is additionally amino-modified or carboxy-modified. The amino group or carboxyl group given by the amino modification or carboxy modification may also be used for covalent bonding with the compound having an antithrombin activity. For example, the amino-modified polyether-modified silicone used in the Examples below (X-22-3939A; Shin-Etsu Chemical) is a preferred example of commercially available hydrophilic polyether-modified silicones.
[0048] In cases where the anti-platelet adhesion copolymer is a partially saponified polyvinyl alcohol, the degree of saponification is preferably 50 to less than 100 mol %, more preferably 74 to 99.9 mol %, still more preferably 78 to 95 mol %, in view of ease of handling and achievement of preferred hydrophilicity. The “degree of saponification” herein means the value calculated by Equation 1.
[0000] Degree of saponification= m /( n+m )×100 Equation 1
[0049] m: number of structures represented by Formula (IV) in polyvinyl alcohol
[0050] n: number of structures represented by Formula (V) in polyvinyl alcohol
[0000]
[0051] In cases where the anti-platelet adhesion copolymer is a copolymer of vinyl pyrrolidone and vinyl acetate, the content of vinyl pyrrolidone units is preferably not less than 50 unit mol %, more preferably not less than 60 unit mol %, in view of ease of handling and achievement of preferred hydrophilicity. On the other hand, the content of vinyl pyrrolidone units is preferably less than 100 unit mol % in view of achievement of a preferred amount of immobilization to the instrument for capturing free thrombi. The ratio of vinyl pyrrolidone units in the copolymer of vinyl pyrrolidone and vinyl acetate (unit mol %) can be calculated by subjecting the copolymer to 1 H-NMR measurement (solvent: CDCl 3 ).
[0052] The binding between the compound having an antithrombin activity and the macromolecular compound is preferably achieved by a covalent bond(s) in view of preventing loss of the compound having an antithrombin activity. The covalent bond(s) can be easily formed by performing coupling reaction that forms an amide bond(s) and/or ester bond(s) between a functional group(s) such as a free amino group(s), carboxyl group(s) and/or hydroxyl group(s) in the compound having an antithrombin activity and such a functional group(s) in the macromolecular compound. The coupling reaction can be carried out by, for example, a conventional method using a commercially available well-known coupling agent such as dicyclohexylcarbodiimide (DCC), and the reaction is also specifically described in the Examples below. In cases where the compound having an antithrombin activity is bound via a covalent bond(s), the antithrombin activity needs to be exerted even after the covalent bonding. Whether or not the antithrombin activity is exerted even after the covalent bonding can be investigated by measuring the antithrombin activity of the conjugate after the covalent bonding by the above-described method. In cases where the compound having an antithrombin activity is a compound represented by the above-described Formula (I), the compound comprises a free amino group at the left end of Formula (I), and a free carboxyl group in R 1 . As described in the Examples below, it has been confirmed that the antithrombin activity is still exerted even after binding with the macromolecular compound via the amino group and/or the carboxyl group. In cases where the macromolecular compound is a polyether-modified silicone, a polyether-modified silicone that is additionally amino-modified or carboxy-modified can be used to form an amide bond or ester bond between the amino group or carboxyl group and the free carboxyl group or amino group of the compound of Formula (I) (Examples below). Further, in cases where the macromolecular compound is a vinyl acetate/polyvinyl pyrrolidone copolymer, an amide bond can be formed between the carboxyl group in the vinyl acetate unit and the amino group in the compound of Formula (I) (Examples below). Further, in cases where the macromolecular compound is a partially saponified polyvinyl alcohol, an ester bond can be formed between the carboxyl group in the compound of Formula (I) and the hydroxyl group in the vinyl alcohol unit (Examples below).
[0053] The amount of the anti-platelet adhesion copolymer adsorbed on the surface(s) of the filter section of the instrument for capturing free thrombi is preferably not less than 0.1 pg/mm 2 , more preferably not less than 1 pg/mm 2 , still more preferably not less than 10 pg/mm 2 . The upper limit of the amount of adsorption is not restricted, and the amount of adsorption is usually not more than 10 ng/mm 2 .
[0054] The amount of adsorption described above is measured by the following method. First, an untreated sensor chip (Sensor Chip Au; GE Healthcare) is pretreated (distilled water at 25° C.; flow rate, 20 μl/min.; 10 minutes) using a surface plasmon resonance apparatus (hereinafter referred to as “SPR”) (BIACORE 3000; GE Healthcare), and the signal value (RU: resonance unit) is measured.
[0055] The material for the filter section of the instrument for capturing free thrombi, that is, the target material of immobilization, is dissolved in a solvent, to prepare a 0.5 wt % solution of the target material of immobilization. A drop of the solution of the target material of immobilization is added to the center of the gold film area of the pretreated sensor chip attached to a spin coater, and the sensor chip is then immediately coated with the target material of immobilization at room temperature by rotation at 3000 rpm for 1 minute.
[0056] After confirming that no droplet is present on the sensor chip, the sensor chip is washed with distilled water using the SPR (25° C.; flow rate, 20 μl/min.; 10 minutes), and the sensor chip is then washed 3 times with 0.025 wt % Triton-X100 solution (25° C.; flow rate, 20 μl/min.; 1 minute), followed by measuring the signal value 10 minutes after completion of the washing.
[0057] Among the thus obtained sensor chips, a sensor chip wherein the difference between the signal values observed before and after the spin coating is within the range of 3000 to 8000 is selected, and the selected sensor chip is washed with distilled water (25° C.; flow rate, 20 μl/min.; 10 minutes), followed by 3 times of washing with 0.025 wt % Triton-X100 solution (25° C.; flow rate, 20 μl/min.; 1 minute)
[0058] Ten minutes after completion of the washing, a solution of the macromolecular compound to be immobilized on the instrument for capturing free thrombi (concentration, 100 μg/ml) is injected (25° C.; flow rate, 20 μl/min.; 1 minute), followed by washing with distilled water (25° C.; flow rate, 20 μl/min.; 3 minutes). The difference between the signal value observed before beginning of the injection (hereinafter referred to as the “signal value A”) and the signal value observed 3 minutes after completion of the injection (hereinafter referred to as the “signal value B”) is calculated, and the resulting value is converted according to the following equation: 1 RU=1 pg/mm 2 .
[0059] Subsequently, the sensor chip is washed with distilled water (25° C.; flow rate, 20 μl/min.; 2 minutes) and then washed 3 times with 0.025 wt % Triton-X100 solution (25° C.; flow rate, 20 μl/min.; 1 minute), further followed by injection of the aqueous solution of the macromolecular compound to be immobilized (concentration, 100 μg/ml) (25° C.; flow rate, 20 μl/min.; 1 minute). Thereafter, the same operation is repeated to calculate the signal difference a total of 5 times (difference between the signal value A and the signal value B), and the average of the obtained values is regarded as the amount of adsorption of the anti-platelet adhesion copolymer to the instrument for capturing free thrombi.
[0060] Examples of the method of immobilizing the above-described conjugate on the surface(s) of the instrument for capturing free thrombi include a method wherein a solution comprising the conjugate as an effective component (surface treatment agent) is brought into contact with the instrument for capturing free thrombi and then a radiation is irradiated thereto, and a method wherein the conjugate dissolved in an organic solvent is applied or sprayed onto the instrument for capturing free thrombi, followed by drying the instrument. The type of the radiation to be irradiated is preferably an electron beam or γ-ray. The concentration of the macromolecular compound solution to be brought into contact with the surface of the instrument is determined using as an index the antithrombin activity. Examples of the index of the antithrombin activity include the concentration in term of argatroban, and the concentration in term of argatroban of the solution of the conjugate to be brought into contact with the surface of the instrument for capturing free thrombi is about 10 to 200,000 ppm by weight, more preferably about 50 to 100,000 ppm by weight, still more preferably about 1,000 to 100,000 ppm by weight. The conjugate is preferably immobilized on at least the filter section of the instrument for capturing free thrombi.
[0061] The instrument for capturing free thrombi is placed in a blood vessel of a living body when it is used. The instrument is preferably retained in a catheter, and placed in a blood vessel by insertion of the catheter into the blood vessel.
EXAMPLES
[0062] Our instruments and methods are described below in detail by way of Examples, but this disclosure is not limited to these.
Example 1
Binding of Amino-Polyether-Modified Silicone with Argatroban
[0063] In an eggplant type flask, 5 mmol of argatroban was placed, and 10 mL of anhydrous dimethylformamide (hereinafter referred to as “anhydrous DMF”) was added thereto to dissolve the argatroban, followed by adding 10 mL of 4 N hydrochloric acid/1,4-dioxane (Togo Kasei Co., Ltd.) dropwise to the resulting solution while cooling the eggplant type flask on ice, and then stirring the resulting mixture for 1 hour. Subsequently, the solvent was evaporated with a rotary evaporator, and the resultant was dried overnight in a vacuum drier, followed by adding 25 mL of anhydrous DMF thereto to provide an argatroban hydrochloride/anhydrous DMF solution.
[0064] The argatroban hydrochloride/anhydrous DMF solution was placed in a two-necked flask in an amount shown in Table 1, and dicyclohexylcarbodiimide (hereinafter referred to as “DCC”)/anhydrous DMF solution and 4-hydroxybenzotriazole (hereinafter referred to as “HOBt”)/anhydrous DMF solution were added thereto with stirring under ice-cooling, followed by further adding an amino-modified polyether-modified silicone (X-22-3939A; Shin-Etsu Chemical) to the resulting mixture and then allowing the reaction to proceed at room temperature for 3 days. Thereafter, the reaction liquid was placed in a dialysis tube (Spectra/Por RC Por 6 MWCO=1000), followed by performing dialysis for 3 days against more than 10 volumes of distilled water while appropriately exchanging the distilled water. The reaction liquid after dialysis was filtered, and the solvent of the obtained filtrate was evaporated with an rotary evaporator, followed by drying the resultant overnight in a vacuum drier, to obtain a conjugate (hereinafter referred to as the “Example 1 conjugate”)
Measurement of Antithrombin Activity of Example 1 Conjugate
[0065] The measurement was carried out using ECA-T Kit (HaemoSys). To 100 μL of the Example 1 conjugate, 900 μL of distilled water was added, to prepare an aqueous Example 1 conjugate solution. Thereafter, 30 μL of the aqueous Example 1 conjugate solution was collected and mixed with 100 μL of ECA prothrombin buffer and 25 μL of SCA-T substrate, and the resulting mixture was incubated at 37° C. for 60 seconds. The mixture was then placed in an apparatus (COATRON M1 (code 80 800 000); Production) and 50 μL of ECA ecarin reagent was further added thereto, followed by performing measurement.
[0066] Measurement using the ECA-T kit was carried out in the same manner as described above except that a mixture prepared by mixing 20 μL of an argatroban solution whose concentration was arbitrarily adjusted using an ethanol/hydrochloric acid (volume ratio, 1/4) mixed solvent with 80 μL of human blood plasma, or a mixture prepared by mixing 20 μL of distilled water as a blank with 80 μL of human blood plasma, was used instead of the aqueous Example 1 conjugate solution. A calibration curve was prepared based on the obtained results. The concentration in term of argatroban of the aqueous Example 1 conjugate solution calculated based on the calibration curve, 1494.3 ppm by weight, was regarded as the value indicating the antithrombin activity of the aqueous Example 1 conjugate solution.
Examples 2 to 13
[0067] The compounds of Example 2 to 13 were obtained in the same manner as Example 1 except that the molar ratios of DCC, HOBt and/or the polyether-modified silicone (X-22-3939A) to the argatroban hydrochloride, and/or the volume ratio of anhydrous DMF to the polyether-modified silicone, were changed. The antithrombic activity was measured for each of these compounds. The molar ratios of DCC, HOBt and the polyether-modified silicone (X-22-3939A) to argatroban hydrochloride, and the result of measurement of the antithrombin activity of each of the compounds of Examples 2 to 13 are shown in Table 1.
[0000]
TABLE 1
Volume ratio
Concentration
Molar ratio to argatroban
of anhydrous
in term of
hydrochloride (1.00)
DMF to poly-
argatroban
X-22-
ether-modified
(ppm by
Compound
DCC
HOBt
3939A
silicone (1)
weight)
Example 1
1.07
1.06
0.060
—
1494.3
Example 2
1.04
1.04
0.060
—
831.2
Example 3
0.20
0.20
0.060
1.4
6610.7
Example 4
0.20
0.20
0.030
3.9
8393.3
Example 5
1.29
1.27
0.493
1.8
505.3
Example 6
1.29
1.27
0.203
4.3
771.7
Example 7
1.29
1.27
0.101
8.6
606.7
Example 8
1.29
1.27
0.067
13.0
441.7
Example 9
1.29
1.27
0.049
17.6
436.7
Example 10
1.29
1.27
0.020
42.9
738.9
Example 11
1.29
1.27
0.010
88.2
895.0
Example 12
1.00
1.00
0.060
—
6000.0
Example 13
1.00
1.00
0.060
40.0
5999.4
[0068] Although the polyether-modified silicone (X-22-3939A) was similarly subjected to measurement of the antithrombin activity, the obtained value was not different from the value for distilled water as the blank, so that it was confirmed that the polyether-modified silicone itself does not have antithrombin activity.
Measurement of Thrombin Inhibition Constant of Example 1 Conjugate
[0069] In 1 mL of physiological saline, 10,000 U of a bovine thrombin solution (ILS Inc.) was dissolved, to prepare an aqueous bovine thrombin solution.
[0070] In 40 mL of distilled water, 25 mg of S-2238 stock solution (Sekisui Medical Co., Ltd.) was dissolved, to prepare an aqueous S-2238 stock solution.
[0071] Using a dilution buffer (0.05 M Tris, 0.1 M NaCl, 1 mg/mL bovine serum albumin (BSA), pH 7.4), each of the aqueous bovine thrombin solution, the aqueous S-2238 stock solution, and the aqueous Example 1 conjugate solution described above was diluted.
[0072] Into a 96-well plate, 100 μL of the diluted aqueous S-2238 stock solution and 50 μL of the diluted aqueous Example 1 conjugate solution were aliquoted, and the plate was sealed, followed by heating the plate in a constant temperature dryer at 37° C. for 30 minutes. Subsequently, 50 μL of the diluted aqueous bovine thrombin solution heated at 37° C. for 30 minutes was further aliquoted, and the absorbance was immediately measured using a microplate reader (measurement wavelength, 405 nm, reference wavelength, 595 nm).
[0073] After completion of the first measurement of absorbance, the second measurement was immediately carried out. The third and later measurements of absorbance were carried out 4, 6, 8, 10, 12, 14, 16, 18 and 20 minutes after the aliquoting of the bovine thrombin dilution, respectively. From the obtained values of absorbance, Ki was calculated from the Lineweaver-Burk plot. Ki of the Example 1 conjugate was 11.2 nM.
[0074] Ki was also calculated for the polyether-modified silicone (X-22-3939A), but Ki of the polyether-modified silicone, which has no antithrombin activity, was the same as that of the blank, as expected.
[0075] Further, as a result of similar calculation of Ki for argatroban, Ki was found to be 39.1 nM, which was not less than 3 times higher than Ki of the Example 1 conjugate.
[0076] From these results, it is clear that the above-described conjugate has extremely high binding affinity to thrombin, and hence that the conjugate can give remarkable antithrombin activity to the instrument for capturing free thrombi, which activity is even higher than that of argatroban, which is known to have antithrombin activity.
Example 14
Binding of Vinyl Acetate-Vinyl Pyrrolidone Copolymer to Argatroban
[0077] In a screw bottle, 14.9 g of tetrahydrofuran, 11.5 g of vinyl acetate, 10.8 g of N-vinyl pyrrolidone, 0.028 g of 2-aminoethanethiol and 0.016 g of azobisisobutyronitrile were placed, and the bottle was sealed, followed by irradiation of ultrasonic waves thereto for 10 minutes. The screw bottle was once opened and bubbling with argon gas was performed for 10 minutes, followed by sealing the bottle again. Thereafter, the screw bottle was immersed, with stirring, in a hot water bath at 60° C. for 1 hour and then in a hot water bath at 70° C. for 6 hours, to allow copolymerization reaction of vinyl acetate and vinyl pyrrolidone. To this reaction liquid, 80 mL of methanol was added, and the resulting mixture was added to about 5 volumes of ether, followed by removal of the supernatant. The operation of adding fresh ether and removing the supernatant was repeated 3 times, and the resultant was dried under reduced pressure, to obtain a vinyl acetate-vinyl pyrrolidone copolymer. The obtained vinyl acetate-vinyl pyrrolidone copolymer was subjected to 1 H-NMR measurement (solvent; CDCl 3 ), and, as a result, the content of vinyl pyrrolidone units was found to be 60.6 unit mol %.
[0078] In 20 mL of anhydrous DMF, 3.58 g of the obtained vinyl acetate-vinyl pyrrolidone copolymer was dissolved, to prepare a vinyl acetate-vinyl pyrrolidone copolymer/anhydrous DMF solution. In a two-necked flask, the whole vinyl acetate-vinyl pyrrolidone copolymer/anhydrous DMF solution prepared and 0.5 mL of argatroban hydrochloride/anhydrous DMF solution (0.49 M) were placed, and 0.5 mL of DCC/anhydrous DMF solution (1.04 M) and 0.5 mL of HOBt/anhydrous DMF solution (1.02 M) were added thereto with stirring under ice-cooling, followed by allowing the reaction to proceed under nitrogen atmosphere at room temperature for 3 days. Subsequently, the reaction liquid was placed in a dialysis tube (Spectra/Por RC Por 6 MWCO=1000), followed by performing dialysis for 3 days against more than 10 volumes of distilled water while appropriately exchanging the distilled water. The reaction liquid after dialysis was filtered, and the solvent of the obtained filtrate was evaporated with a rotary evaporator, followed by drying the resultant overnight in a vacuum drier, to obtain a conjugate (hereinafter referred to as the “Example 14 conjugate”).
Measurement of Antithrombin Activity of Example 14 Conjugate
[0079] In the same manner as the measurement of antithrombin activity of the Example 1 conjugate, measurement was carried out for the Example 14 conjugate/methanol solution (concentration, 20 wt %). The calculated concentration in term of argatroban of the Example 14 conjugate/methanol solution, 104.1 ppm, was regarded as the value indicating the antithrombin activity of the Example 14 conjugate/methanol solution.
Immobilization of Example 1 Conjugate to PET Mesh
[0080] Bis-Tris (Dojindo Laboratories) and sodium chloride were dissolved in ultrapure water such that their final concentrations were 0.25 M and 0.5 M, respectively, and 6 N hydrochloric acid was added dropwise to the resulting solution to adjust the pH to 5, to prepare 5× Bis-Tris buffer.
[0081] A PET mesh (fiber diameter, 27 μm; mesh size, 100 μm) was formed into a 6-cm square. The Example 1 conjugate at a concentration in term of argatroban of 50,000 ppm by weight, propylene glycol, 5× Bis-Tris buffer and distilled water were mixed together at a volume ratio of 8/50/20/22, to obtain a treatment liquid.
[0082] The formed PET mesh was rolled into a cylindrical shape and inserted into a polypropylene centrifuge tube, followed by adding 5 mL of the treatment liquid thereto. After irradiation of ultrasonic waves to the tube in a warm bath at 40° C. for 1 hour, γ-ray was further irradiated thereto with an absorbed dose of 25 kGy for 3 hours.
[0083] Thereafter, the treatment liquid in the centrifuge tube was removed, and 15 mL of 0.025 wt % aqueous polyoxyethylene octylphenyl ether solution was added to the centrifuge tube, followed by shaking the centrifuge tube for 10 minutes to wash the PET mesh. Thereafter, the aqueous solution in the centrifuge tube was removed, and 15 mL of fresh 0.025 wt % aqueous polyoxyethylene octylphenyl ether solution was added to the centrifuge tube, followed by 10 minutes of shaking This washing operation was repeated a total of 3 times. Subsequently, the same washing operation was repeated 10 times using 15 mL each of distilled water and physiological saline, to prepare a PET mesh to which the Example 1 conjugate was immobilized (hereinafter referred to as the “PET mesh L”).
[0084] The PET meshes M to P were prepared by the same operation as in the preparation of the PET mesh L except that the treatment liquids prepared with the volume ratios shown in Table 2 were used instead of the above treatment liquid.
[0000]
TABLE 2
Mixing volume ratio
Example 1 Compound at
concentration in term
of argatroban of
Propylene
5 × Bis-
Distilled
PET mesh
50,000 ppm by weight
glycol
Tris buffer
water
L
8
50
20
22
M
0.2
50
20
29.8
N
2
30
20
48
O
4
30
20
46
P
16
50
20
14
[0085] The PET mesh Q was prepared by the same operation as in the preparation of the PET mesh L except that distilled water was used instead of the above treatment liquid.
Measurement of Amount of Example 1 Conjugate Eluted
[0086] The PET mesh L formed into a 6-mm square was placed in a polystyrene round tube (Code: 352054; BECTON DICKINSON), and 5 mL of human blood plasma was added thereto, followed by shaking the tube for 4 hours. The concentration of the Example 1 conjugate in the human blood plasma after shaking was below the detection limit of the SCA-T kit used for the measurement, and hence no elution of the Example 1 conjugate from the PET mesh L was found. This result indicates that the above conjugate can be strongly immobilized on the instrument for capturing free thrombi.
Evaluation of Amount of Anti-Platelet Adhesion Copolymer Immobilized
[0087] As examples of the copolymer of vinyl pyrrolidone and vinyl acetate (hereinafter referred to as “VA copolymer”) to be used as the anti-platelet adhesion copolymer constituting the above conjugate, PVP(K-90), VA73, VA64, VA55 and VA37 (all of these were obtained from BASF) were provided. Similarly, as examples of the partially saponified polyvinyl alcohol to be used as the anti-platelet adhesion copolymer, PVA217, PVA417 and PVA205c (all of these were obtained from Kuraray Co., Ltd.) were provided. Further, as polyether-modified silicones, F114, F244, F303, F3031, F348, F350s, F502, F506 and X-22-3939A (all of these were obtained from Shin-Etsu Silicone, Co., Ltd.) were provided. Each of the VA copolymers, partially saponified polyvinyl alcohols and polyether-modified silicones provided was diluted with distilled water to prepare its aqueous solution at 10,000 ppm by weight.
[0088] On the other hand, for comparison, PEG2000, PEG4000, PEG6000 and PEG20000 (all of these were obtained from Nacalai Tesque); and PEG methyl ether (PEG-em) and PEG dimethyl ether (PEG-dm) (both were obtained from Sigma-Aldrich); were provided as macromolecular compounds that are not included in the anti-platelet adhesion copolymer constituting the above conjugate. Each macromolecular compound provided was diluted with distilled water to prepare its aqueous solution at 10000 ppm by weight.
[0089] Binding of argatroban to the above VA copolymer or polyether-modified silicone, binding of argatroban to the partially saponified polyvinyl alcohol, and binding of argatroban to PEG2000, PEG4000, PEG6000 or PEG20000 (all of these were obtained from Nacalai Tesque), or to PEG methyl ether (PEG-em) or PEG dimethyl ether (PEG-dm), were carried out in the same manner as in Example 14 or Example 1.
[0090] As examples of the 0.5 wt % solution of the target material of immobilization, on which the anti-platelet adhesion copolymer is to be immobilized, a PMMA (weight average molecular weight, 93000; Sigma-Aldrich)/toluene solution, polyurethane/dimethylacetamide solution, PSf (UDEL (registered trademark), manufactured by Solvay; P-3500)/dimethylacetamide solution, polyvinyl chloride (weight average molecular weight, 80000; Sigma-Aldrich)/tetrahydrofuran solution, polystyrene (Wako)/chloroform solution, and polycarbonate (weight average molecular weight, 20000; TEIJIN Ltd.)/chloroform solution were prepared.
[0091] The amount of adsorption of each of the various anti-platelet adhesion copolymers to each target material of immobilization was measured. The results are shown in Table 3.
[0000]
TABLE 3
Signal value B-Signal value A [pg/mm 2 ]
Target material of adsorption
Poly-
Poly-
Polyvinyl
Poly-
Poly-
PMMA
sulfone
urethane
chloride
styrene
carbonate
Macromolecular
PVPK90
789
—
—
—
—
—
compound
VA37
2760
—
—
—
—
—
that inhibits
VA55
472
—
—
—
—
—
adhesion of
VA64
920
—
—
—
—
—
platelets
VA73
426
—
—
—
—
—
PVA217
2529
2886
1635
2468
2777
2356
PVA417
2475
2742
1911
2330
2662
2346
PVA205c
2223
2130
1411
1796
1989
1819
F114
1003
844
514
739
621
756
F244
1639
1272
1144
1118
1052
1243
F303
1268
1156
1604
1037
—
1374
F3031
947
559
614
418
339
536
F348
875
784
756
608
283
800
F350s
751
657
674
544
275
591
F502
827
657
696
385
197
482
F506
691
308
437
167
43
279
X-22-
1182
910
1204
695
924
1424
3939A
PEG2000
2
—
—
—
—
—
PEG4000
2
—
—
—
—
—
PEG6000
5
—
—
—
—
—
PEG20000
113
—
—
—
—
—
PEG-me
5
—
—
—
—
—
PEG-dm
67
—
—
—
—
—
[0092] From the results shown in Table 3, it is clear that the anti-platelet adhesion copolymer constituting the above-described conjugate is not limited to the polyether-modified silicone (X-22-3939A), and that strong immobilization on the instrument for capturing free thrombi is possible.
Evaluation of Number of Platelets Adhered
[0093] The PET mesh L formed into a 1-cm square was placed in an arbitrary well of a 24-well plate, and 1 mL of phosphate buffered saline (hereinafter referred to as “PBS(−)”) was added to the well, followed by incubation of the plate at 37° C. for 30 minutes.
[0094] Platelet rich plasma (hereinafter referred to as “PRP”) was prepared by mixing 3.2 wt % aqueous sodium citrate solution with human volunteer blood at a volume ratio of 1/9 and then centrifuging the resulting mixture at 20° C. at 1000 rpm for 15 minutes. The platelet number in PRP was preliminarily measured using Automated Hematology Analyzer XT-1800i (Sysmex Corporation).
[0095] The PET mesh L after incubation was transferred to an empty well, and 1 mL of the prepared PRP was added thereto, followed by additional incubation of the mesh at 37° C. for 2 hours. This PET mesh L was held with tweezers and placed in another well containing 1 mL of PBS(−), followed by gently washing the mesh. This washing operation was repeated a total of 3 times. The whole PBS(−) used in the washing was collected in an empty well.
[0096] To the collected PBS(−), 1 mL of 1 wt % polyoxyethylene octylphenyl ether/PBS(−) was added, and the resulting mixture was incubated at 37° C. for 15 minutes.
[0097] To an empty well, 200 μL of the incubated solution was collected, and 200 μL of PBS(−) was added thereto. To the resulting mixture, 400 μL of Solution C (a mixture prepared by mixing Solution A with Solution B of LDH Cytotoxicity Detection Kit (manufactured by Takara Bio Inc.) at a volume ratio of 1/45) was added immediately after its preparation, and the well was covered with aluminum foil, followed by leaving the mixture to stand at room temperature for 30 minutes. The reaction was then terminated by addition of 200 μL of 1N HCl (final concentration, 0.2 N).
[0098] The reaction liquid after termination of the reaction was subjected to measurement of absorbance at a wavelength of 490 nm using a spectrophotometer.
[0099] The same operation was carried out also for the PET meshes M to Q, and each reaction liquid after the termination of reaction was subjected to measurement of absorbance at a wavelength of 490 nm.
[0100] The PRP was diluted with PBS(−) to concentrations of 1/10, 1/20, 1/50, 1/100, 1/500 and 1/1000. Each diluted PRP solution was collected into an empty well of a 24-well plate in an amount of 200 μL, and 200 μL of 1% polyoxyethylene octylphenyl ether/PBS(−) was added thereto, followed by incubating the resulting mixture at 37° C. for 15 minutes. Each solution after the incubation was collected into an empty well in an amount of 200 μL, and 400 μL of Solution C immediately after preparation was added to the well. The well was covered with aluminum foil, and the mixture was left to stand at room temperature for 30 minutes. Thereafter, 200 μL of 1 N HCl (final concentration, 0.2 N) was added thereto. The reaction liquids were subjected to measurement of absorbance at a wavelength of 490 nm using a spectrophotometer, to prepare a calibration curve.
[0101] From the prepared calibration curve and the absorbance at a wavelength of 490 nm of each of the reaction liquids obtained by the treatment with the PET meshes L to Q, the platelet number in each reaction liquid was calculated. The platelet number in the reaction liquid obtained by the treatment with the PET mesh Q was defined as 100% to calculate the ratios of the platelet numbers in the other reaction liquids (hereinafter referred to as “relative ratios”). The results are shown in FIG. 1 .
[0102] From the results in FIG. 1 , it is clear that the above conjugate is capable of giving remarkable anti-platelet adhesion capacity to the instrument for capturing free thrombi.
Measurement of Whole Blood Clotting Time
[0103] Blood collected from a volunteer was mixed with citric acid at a volume ratio of 9/1, to prepare citrated blood.
[0104] In a cuvette (NON-ACTIVATED CLOTTING TEST KIT), 18 μL of physiological saline was placed, and 14.8 μL of Calcicol was added thereto, followed by further adding 342 μL of the citrated blood to the resulting mixture. The mixture was then subjected to measurement using a Sonoclot coagulation & Platelet Function Analyzer (IMI Corporation), and the obtained ACT ONSET value was regarded as the whole blood clotting time. The whole blood clotting time of the blood collected from the volunteer was 545 seconds.
[0105] The same measurement was carried out using each of 2, 10 and 20 μM argatroban solutions (solvent: methanol/hydrochloric acid (volume ratio, 4/1)) instead of physiological saline. As a result, the whole blood clotting time was 531, 746 and 849 seconds, respectively.
[0106] The same measurement was carried out using each of 0.3, 1.3 and 2.5 μM aqueous Example 1 conjugate solutions instead of physiological saline. As a result, the whole blood clotting time was 527, 693 and 730 seconds, respectively.
Preparation of Instrument for Capturing Free Thrombi
[0107] A nitinol wire was bent and turned a plurality of times into a ring shape to prepare a ring-shaped section 12 that is a circular ring having a diameter of 6 mm. A polyester mesh sheet having a 100-μm mesh size was formed into a conical-bag shape having a height of 15 mm, to prepare a filter section 13 . In this case, the bottom of the cone corresponds to the open end 13 a , and the top corresponds to the closed end 13 b.
[0108] As the core section 11 (including an operation member 15 ), a stainless-steel wire was used. At one end of the wire, a guide section 11 b composed of a flexible wire gently curving to form an arc was formed.
[0109] The core section 11 was made to penetrate the ring-shaped section 12 , and the closed end 13 b of the filter section 13 was attached to the core section 11 at a position in the proximal side of the guide section at the distal end of the core section 11 . Further, the open end 13 a of the filter section 13 was attached to the ring-shaped section 12 . Four threads made of a synthetic resin or composite fiber, such as polyarylate threads, were provided, and each of these was used as a support wire section 14 . A position on the core section 11 that is proximal to the ring 12 was used as a support section 14 a , and each of the positions defined by dividing the circumference of the ring-shaped section 12 into four equal parts was defined as a support section 14 b . As shown in FIG. 2 , each of the four support wire sections 14 was fixed to the support section 14 a and the support section 14 b by adhesion or the like, to complete a filter instrument A. In the ring-shaped section 12 , as shown in FIG. 2 , a dividing point 12 1 , dividing point 12 2 , dividing point 12 3 and dividing point 12 4 were set at the midpoints of the support sections 14 b , and a folding property was preliminarily given to the ring-shaped section 12 such that the dividing point 12 1 and the dividing point 12 3 , a pair of the dividing points facing each other, become the bottoms of valleys when these dividing points are bent by an external force in the direction of the proximal end 15 a of the core section, while the dividing point 12 2 and the dividing point 12 4 , the other pair of the dividing points, become the tops of mountains when these dividing points are bent by an external force in the direction of the distal end of the core section, that is, such that the ring-shaped section 12 shows a wavy pattern as a whole after folding.
[0110] The state of the filter instrument A changes from the spread state shown in FIG. 2 to the folded state by a process in which the support wire sections 14 are bundled with the core section 11 as shown in FIG. 3 by the action of an external force to cause bundling of the support sections 14 b with the core section, which makes the two pairs of dividing points that face each other, that is, the pair of the dividing point 12 1 and the dividing point 12 3 , and the pair of the dividing point 12 2 and the dividing point 12 4 , become the bottoms of valleys and the tops of mountains, respectively, while the filter section 13 is folded as the ring-shaped section 12 is gradually folded until the paired dividing points come into contact with each other by the folding of the ring-shaped section 12 as shown in FIG. 4 . In the folded state, the open end 13 a of the filter section 13 is almost completely closed.
Immobilization of Example 1 Conjugate on Instrument for Capturing Free Thrombi
[0111] The Example 1 conjugate at a concentration in term of argatroban of 50,000 ppm by weight, propylene glycol, 5× Bis-Tris buffer and distilled water were mixed together at a volume ratio of 8/50/20/22, to obtain a treatment liquid.
[0112] In a container with an appropriate capacity, 2 mL of the treatment liquid was placed, and the filter section of the prepared filter instrument A was completely immersed therein, followed by irradiation of ultrasonic waves to the filter section in a warm bath at 40° C. for 1 hour and then irradiation of γ-ray with an absorbed dose of 5 kGy for 3 hours.
[0113] Thereafter, the filter instrument A was transferred to a polypropylene centrifuge tube containing 15 mL of 0.025 wt % aqueous polyoxyethylene octylphenyl ether solution, and the 10-cm portion at the distal end was immersed in the aqueous solution, followed by leaving the instrument to stand for 10 minutes. Thereafter, the aqueous solution in the centrifuge tube was removed, and 15 mL of fresh 0.025 wt % aqueous polyoxyethylene octylphenyl ether solution was added thereto, followed by leaving the instrument to stand for 10 minutes. This washing operation was repeated a total of 4 times. Subsequently, the same washing operation was repeated 10 times using 15 mL each of distilled water and physiological saline, and the instrument was then subjected to drying under reduced pressure and EOG sterilization, to prepare a filter instrument A on which the Example 1 conjugate was immobilized (hereinafter referred to as the “instrument for capturing free thrombi X”).
[0114] As a control experiment, a filter instrument A separately prepared was subjected to only EOG sterilization, to provide a filter instrument A to which the Example 1 conjugate is not immobilized (hereinafter referred to as the “instrument for capturing free thrombi Y”).
In Vivo Placement Test
[0115] The instrument for capturing free thrombi X was contracted to a diameter of 3 Fr, and stored in a catheter. A dog (hybrid beagle) was subjected to measurement of the whole blood clotting time (hereinafter referred to as “ACT”), and 1500 units of a heparin injection was administered to the dog. Thereafter, ACT was measured again to confirm that ACT was within the range of 200 to 300 s.
[0116] Into the above dog, a 7-Fr sheath catheter was inserted, and a 6-Fr guide catheter was further inserted, followed by administration of a contrast medium to determine the blood vessel where the instrument for capturing free thrombi X was to be placed. The instrument for capturing free thrombi X stored in the catheter was then delivered to the carotid artery of the dog (blood vessel diameter, 6 mm). The filter section of the instrument for capturing free thrombi X delivered to the desired site was opened to begin indwelling of the instrument for capturing free thrombi X. Thereafter, a contrast medium was administered to see whether or not blood was passing through the filter section of the instrument for capturing free thrombi X. Administration of an anticoagulant, such as heparin, was not carried out at all.
[0117] ACT of the dog became a normal value about 2 hours after the administration of a heparin injection. However, as a result of the test, inhibition of blood flow by the placed instrument for capturing free thrombi X was not observed, and blood was capable of stably passing through the instrument for capturing free thrombi X for not less than 5 hours after the beginning of indwelling.
[0118] The same operation as described above was carried out except that the instrument for capturing free thrombi C was used instead of the instrument for capturing free thrombi X to see whether or not blood was passing through the filter section of the instrument for capturing free thrombi Y. As a result of the test, inhibition of blood flow by the instrument for capturing free thrombi Y was found, and the filter section of the instrument for capturing free thrombi Y was occluded 15 minutes after the beginning of indwelling. On the filter section of the instrument for capturing free thrombi Y recovered, formation of thrombi and membranous deposits was found.
[0119] The same operation as described above was carried out except that the instrument for capturing free thrombi Y was used instead of the instrument for capturing free thrombi X, and that heparin was continuously administered during the test, to see whether or not blood was passing through the filter section of the instrument for capturing free thrombi Y. As a result of the test, inhibition of blood flow by the instrument for capturing free thrombi Y was found even with the continuous administration of heparin, and the filter section of the instrument for capturing free thrombi Y was occluded 30 minutes after the beginning of indwelling. On the filter section of the instrument for capturing free thrombi Y recovered, formation of thrombi and membranous deposits was found.
Example 15
[0120] In an eggplant type flask, 44.8 mmol of argatroban was placed, and 50 mL of anhydrous dimethylformamide (hereinafter referred to as “anhydrous DMF”) was added thereto under Ar gas flow to dissolve argatroban, followed by cooling the eggplant type flask on ice. To the resulting solution, 50 mL of 4 N hydrochloric acid/1,4-dioxane (Togo Kasei Co., Ltd.) was added dropwise, and the resulting mixture was stirred at room temperature for 1 hour. Subsequently, the solvent was evaporated with a rotary evaporator, and the resultant was subjected to azeotropic distillation treatment with anhydrous toluene (Wako). The resultant was further dried overnight in a vacuum drier, and anhydrous DMF was added to the obtained compound to provide an argatroban hydrochloride/anhydrous DMF solution (1.0 M).
[0121] In a three-necked flask, 46 ml of the argatroban hydrochloride/anhydrous DMF solution was placed, and 57.8 mmol of HOBt and 20 ml of anhydrous DMF were added thereto with stirring under ice-cooling. After dissolving the reagent, 51.0 mmol of DCC was added thereto. To 190 g of amino-polyether-modified silicone (X-22-3939A; Shin-Etsu Chemical) preliminarily dried under reduced pressure at 40° C. for 5 hours, 760 g of anhydrous DMF was added, and the resulting mixture was stirred. The solution of argatroban hydrochloride, DCC and HOBt in anhydrous DMF was added to the amino-polyether-modified silicone/anhydrous DMF solution under ice-cooling. After repeating degassing and replacement of the atmosphere with Ar 5 times, the mixture was allowed to react at room temperature for 3 days with stirring. The reaction liquid was placed in a dialysis tube (Spectra/Por RC Por 6 MWCO=15,000), followed by performing dialysis for 7 days against more than 100 volumes of distilled water while appropriately exchanging the distilled water. The reaction liquid after dialysis was filtered, and the solvent of the obtained filtrate was evaporated with a rotary evaporator, followed by drying the resultant overnight in a vacuum drier, to obtain a conjugate (hereinafter referred to as the “Example 15 conjugate”).
Measurement of Antithrombin Activity of Example 15 Conjugate
[0122] The measurement was carried out using ECA-T Kit (HaemoSys). To 10 mg of the Example 15 conjugate, 1 ml of distilled water was added, to prepare an aqueous Example 15 conjugate solution. Thereafter, 30 μL of the aqueous Example 15 conjugate solution was collected and mixed with 100 μL of ECA prothrombin buffer and 25 μL of ECA-T substrate, and the resulting mixture was incubated at 37° C. for 60 seconds. The mixture was then placed in an apparatus (COATRON M1 (code 80 800 000); Production) and 50 μL of ECA ecarin reagent was further added thereto, followed by performing the measurement.
[0123] Measurement using the ECA-T kit was carried out in the same manner as described above except that a mixture prepared by mixing 20 μL of an argatroban solution whose concentration was arbitrarily adjusted using an ethanol/hydrochloric acid (volume ratio, 1/4) mixed solvent with 80 μL of human blood plasma, or a mixture prepared by mixing 20 μL of distilled water as a blank with 80 μL of human blood plasma, was used instead of the aqueous Example 15 conjugate solution. A calibration curve was prepared based on the obtained results. The concentration in term of argatroban of the aqueous Example 15 conjugate solution calculated based on the calibration curve, 2.6 ppm by weight, was regarded as the value indicating the antithrombin activity of the aqueous Example 15 conjugate solution.
Immobilization of Example 15 Conjugate to Instrument for Capturing Free Thrombi
[0124] The Example 15 conjugate at a concentration in term of argatroban of 344 ppm by weight, propylene glycol, 5× Bis-Tris buffer and distilled water were mixed together at a volume ratio of 10/50/20/20, to obtain a treatment liquid.
[0125] In a container with an appropriate capacity, 2 mL of the treatment liquid was placed, and the filter section of the prepared filter instrument B was completely immersed therein, followed by irradiation of ultrasonic waves to the filter section in a warm bath at 40° C. for 1 hour and then irradiation of γ-ray with an absorbed dose of 5 kGy for 3 hours.
[0126] Thereafter, the filter instrument B was transferred to a polypropylene centrifuge tube containing 15 mL of 0.025 wt % aqueous polyoxyethylene octylphenyl ether solution, and the 10-cm portion at the distal end was immersed in the aqueous solution, followed by leaving the instrument to stand for 10 minutes. Thereafter, the aqueous solution in the centrifuge tube was removed, and 15 mL of fresh 0.025 wt % aqueous polyoxyethylene octylphenyl ether solution was added thereto, followed by leaving the instrument to stand for 10 minutes. This washing operation was repeated a total of 4 times. Subsequently, the same washing operation was repeated 10 times using 15 mL each of distilled water and physiological saline. The instrument was then further immersed in 15 ml of distilled water for 30 minutes, and subjected to drying under reduced pressure and EOG sterilization to prepare a filter instrument B to which the Example 15 conjugate was immobilized (hereinafter referred to as the “instrument for capturing free thrombi Z”).
In Vivo Placement Test
[0127] The instrument for capturing free thrombi X was contracted to a diameter of 3 Fr, and stored in a catheter. A dog (hybrid beagle) was subjected to measurement of the whole blood clotting time (hereinafter referred to as “ACT”), and a heparin injection was administered to the dog. Thereafter, ACT was measured again to confirm that ACT was not less than 300 s.
[0128] To the above dog, a 7-Fr sheath catheter was inserted, and a 6-Fr guide catheter was further inserted, followed by administration of a contrast medium to determine the blood vessel where the instrument for capturing free thrombi X was to be placed. The instrument for capturing free thrombi Z stored in the catheter was then delivered to the carotid artery of the dog (blood vessel diameter, 6 mm). The filter section of the instrument for capturing free thrombi Z delivered to the desired site was opened to begin indwelling of the instrument for capturing free thrombi Z. Thereafter, a contrast medium was administered to see whether or not blood was passing through the filter section of the instrument for capturing free thrombi X. During the test, an anticoagulant such as heparin was administered to maintain an ACT of not less than 300 s.
[0129] As a result of the test, inhibition of blood flow by the placed instrument for capturing free thrombi Z was not observed, and blood was capable of passing through the instrument for capturing free thrombi Z for not less than 5 hours after the beginning of indwelling.
[0130] From these results, it is clear that the above conjugate is capable of giving remarkable anticoagulant action to the instrument for capturing free thrombi.
INDUSTRIAL APPLICABILITY
[0131] Our instruments and method can be used to capture free thrombi having excellent anticoagulant action in the field of medicine. | An instrument captures free thrombi by inhibiting blood coagulation reaction at the stage of primary hemostasis, in which platelets are involved, and at the stage of coagulation thrombus formation, in which blood coagulation factors are involved, thereby securely capturing free thrombi and extending the available time of the instrument. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to fender piles and fendering systems, and more particularly to prestressed concrete fender piles having limited prestressing to allow for greater elasticity in bending and greater energy absorption.
Fender systems are used to protect waterfront piers, wharves, docks, and the like from the hazards of ship mooring and berthing. Berthing facilities and ships are subjected to various types of contact and loading during the mooring process or during berthing periods. Contacts between ship and fender system may be in the form of heavy impact, abrasive action from vessels, or direct pressure. Such contacts may cause extensive damage to the ship and to the pier structure if suitable means are not employed to counteract them. Fender piles are a key element developed for this purpose. Impact energy upon a fender pile is absorbed by deflection. Energy-absorption capacity depends on size, length, penetration, and material of the pile, and is determined on the basis of internal strain-energy characteristics. Fender systems are a troublesome and expensive high maintenance item for port operators because they are subject to frequent damage. A key to the performance of the fender system is the line of fender piles which guard a pier, receive the loads from the impact of ships, and distribute attenuated reactions to the seafloor soil and to appropriate locations on the pier.
More conventional fender piles are made from steel or timber. On a system basis, a large energy-absorbing rubber fender is required in a steel system to absorb ship impact energy, and steel is highly subject to rust and corrosion. Timber systems, on the other hand, are very good energy absorbers, but the total energy that timber pile can absorb is severely limited.
To overcome the constraints of steel and timber pile systems, prestressed concrete fender piles were developed that, on a pile-for-pile basis, can absorb significantly more energy than either steel or timber piles. In addition, using the prestressed concrete fender piles of the present invention, a prestressed concrete fender system is more cost effective than a more conventional fender system made from steel or timber piles. In addition to surpassing conventional steel and timber piles in terms of economics and energy absorption, the prestressed concrete piles of this invention also surpass in durability.
SUMMARY OF THE INVENTION
It is an object of the invention, therefore, to provide a prestressed concrete high energy absorbing pile having high elasticity.
Another object of the invention is to provide a prestressed concrete high energy absorbing pile having partially prestressed reinforcing strands which allow substantial elasticity in bending and return of the pile to its original form following energy absorption.
A further object of the invention is to provide a cost effective prestressed concrete pile for replacing conventional timber and steel fender piles.
Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a typical basic fendering system using prestressed concrete piles.
FIG. 2 is a top view of the fendering system shown in FIG. 1.
FIG. 3 is a graph showing moment-curvature relationship for a typical prestressed concrete fender pile.
FIG. 4 is a cross sectional side elevational view of typical high-energy-absorbing prestressed concrete fender pile of this invention.
FIG. 5 is cross sectional view, taken along line 5--5 of FIG. 4, using prestressed strands in a square pattern.
FIG. 6 is a cross sectional view, which also can be taken along line 5--5 of FIG. 4, but which uses 14 prestressed strands positioned in four rows.
FIG. 7 is a cross sectional view of a high-energy-absorbing prestressed concrete pile using prestressed and unstressed strands.
FIG. 8 is a cross sectional view of a prestressed concrete pile using prestressed strands in a circular pattern.
FIG. 9 is a cross sectional view of an octagonal prestressed concrete pile.
FIG. 10 shows a partial plan view of a very high energy absorbing fendering system using closely spaced high-energy-absorbing prestressed concrete piles and a foam filled fender.
FIG. 11 is a partial front elevational view of the fendering system shown in FIG. 10.
FIG. 12 also shows a very high energy absorbing fendering system using high-energy-absorbing prestressed concrete fender piles in conjunction with a prestressed concrete slab and foam filled fender.
FIG. 13 is a partial front elevational view of the fendering system shown in FIG. 12.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A fendering system utilizing high-energy-absorbing prestressed concrete fender piles is shown in a basic form in FIGS. 1 and 2. A row of high-energy-absorbing prestressed concrete piles 10 are driven into the seafloor 11, as shown, adjacent wharf or pier 12. The fender piles 10 distribute ship impact energy to other members of the fendering system. The piles deflect (elastically), absorbing all or some of the impact energy, and transfer a reaction to the pier 12. A waler 14 and elastomeric/rubber fenders 16 can be placed at the head of piles 10, as shown to absorb energy in addition to that absorbed by the piles. By making the fender piles 10 a part of the energy-absorbtion system, the piles are used more efficiently, producing a more effective and economical fender system. Log camels 18 are used at the waterline to distribute ship berthing impact among the piles. Timber is used for the whaler 14 and chocks 19 between piles.
Other means for incorporating prestressed concrete piles into fender systems include substituting concrete or steel for the timber wale/chock system described above. Besides the cylindrical elastomeric/rubber fenders 16, other elastomeric fenders, such as the v-type and buckling cell, can be used.
The preferred embodiment of a high-energy-absorbing prestressed concrete pile of the present invention, one which has the most energy absorbing capability, is a square pile with prestressing reinforcing strands in a rectangular pattern stressed to a level of 60 ksi in the strands. This low initial stress means there is an additional 180 ksi of material strength remaining for use in absorbing impact prior to reaching the yield strength of the strands. This stress range maximizes the energy that can be absorbed by the pile.
Pile performance in the working stress range is essentially independent of concrete strength but is highly dependent on prestressing force and stress in the strands. However, the ultimate total energy absorption of the pile is dependent on concrete strength. A high-strength, high-quality concrete, such as normal-weight 8000-psi concrete is preferred. This strength concrete can be achieved economically. Such concrete is desirable because it provides both higher moment capacity and higher ultimate curvature than lower unit weight concretes. High-strength, high-quality concrete also has reduced permeability and hence reduces corrosion potential of the reinforcing strands, thereby enhancing durability.
Adequate curvature of the pile cross-section under load is necessary to create an energy-absorbing pile. Curvature (rotational capacity of the cross-section) is related to the reinforcing steel strain range. High-strength reinforcement (prestressing strand) is used to maximize the curvature. The optimum energy-absorbing condition is achieved when the tension reinforcement yields at the same time as the concrete compression strain reaches 0.003 inch/inch. In this condition, the pile remains basically elastic (bilinear) and will essentially return to its original shape after unloading.
All fender piles must be able to withstand a frequently occurring impact without damage to the pile. Some damage is acceptable for a rare and extreme event. The ability of a concrete pile to withstand an extreme event is defined as that point where the concrete shell of the prestressed pile spalls and exposes the reinforcing steel. This type of damage requires repairs or replacement of the damaged piles. However, this does not mean that the pile has failed, as the pile can still absorb a significant amount of additional energy as part of the functioning fender system if it properly reinforced for ductile performance.
As shown on the curve of FIG. 3, high-energy-absorbing prestressed concrete fender piles develop serviceable cracks at relatively low energy (i.e., moment) input. The upper limit of serviceability for the pile, however, is that point where the outer shell of the pile fails by crushing of the concrete and spalling of the cover over the spiral reinforcing and tensioned steel strands. A large amount of usable energy can be absorbed after the initial cracking of the pile and before spalling of the concrete shell.
While some serviceable cracking occurs from berthing impacts in the relatively elastic piles, the prestressing forces close the cracks following the berthing impact, thus inhibiting corrosion of the reinforcing steel strands.
The design is focused on energy developed in a deflected pile prior to reaching the ultimate moment capacity of the pile. To limit potential permanent set, the prestressing steel is designed to remain elastic until the concrete reaches its ultimate capacity at a 0.003 inch/inch strain. The resultant moment-curvature relationship for the cross section is approximated as the bilinear curve, shown in FIG. 3. The initial curve or slope is steeper because the concrete has not cracked. After the concrete cracks, the curve flattens out. The amount of prestressing steel reinforcement, the degree to which it is prestressed, and its location in the pile cross-section directly influence the ultimate moment and curvature capacities of the cross-section.
Soft piles are defined as having a relatively low reaction to energy ratio (i.e., R/E 1/4 1.0). The R/E ratio is calculated at an ultimate concrete strain of 0.003 inch/inch. The number of steel reinforcing strands used for soft piles is based on the pile cross-section and an effective tensioning in the strands of approximately 60 ksi. This provides a usable elastic steel stress range (i.e., stress range) of 240 minus 60=180 ksi. This range is three times as great as that for mild steel reinforcement.
A stiff pile with lower energy-absorbing capacity contains a higher effective prestress with the strands arranged in either concentric or eccentric patterns. Stiff piles are defined here as having a high reaction to energy ratio (i.e., R/E 1/2 1.3). For eccentricically prestressed piles, a minimum prestress level of 400 psi along one side may be used to minimize potential for surface cracking of the piles during driving and handling.
A typical high-energy-absorbing prestressed concrete pile 40 is shown in FIG. 4 having vertical reinforcing rebar 42 and stressed strands 44, together with spiral outside reinforcement wire 46. In the preferred embodiments discussed herein, all variations of the pile use 1/2-inch diameter, 270 ksi, 7 wire, low relaxation prestressing strands, and an effective compressive prestress of 450 psi. The concrete is confined by spiral 42 made of W11 cold drawn wire. High strength concrete is employed having a compressive strength at 28 days of 8,000 psi. An 18-inch square cross section is used in all but one of the examples described below; however, within the scope of the disclosure, other rectangular, polygonal or circular cross sections are possible and concentrically or eccentricallly prestressing can be used. Pile length is dependent on application but is typically 65 feet. Various cross-sectional configurations are depicted in FIGS. 5, 6, 7, 8 and 9, by way of example.
The cross-sectional configuration of FIG. 5 contains sixteen prestressed strands 44 spaced approximately 2-inches apart at their closest proximity to each other toward the front and back sides of the pile, in a square formation as shown; a row of six strands at front and back, respectively, with a single strand spaced inwardly toward the pile center from each end of the six-strand rows. In addition, two rebar reinforcements 42, located at either side, and cross ties 55 can be used, if desired. Where cross-ties are not used, rebar 42 can be omitted as it is only used to anchor the cross ties in the sideways position. With the exception of approximately 5 turns at a pitch of 11/2 inches at either end of pile 40, spiral outside reinforcement 46 is wound at a 3-inch pitch along the entire length of the pile.
In the configuration, as shown in FIG. 6, there are three prestressed strands 61 and two rebars 63 positioned alternately in a row along the front and back of the pile. A row of five equally spaced prestressed strands 65 are located at the same spacing inwardly from each end of the front and back rows, respectively. Rebars 67 are located similarly to rebars 53 in FIG. 5, and also may be eliminated if optional cross ties 68 are not used. This configuration represents a pile with the greatest energy-absorbing characteristics and the lowest reaction to energy relationship. The prestressing steel strands 61 do not yield prior to reaching ultimate strength of the pile.
The configuration of FIG. 7 is the same as FIG. 5 only with respect to the front and back rows of prestressed strands 71. Spaced inwardly from the back side of the pile, a distance equal to the spacing between strands 71, are four unstressed strands 73, as shown. The unstressed strands 73 contribute to improve the failure characteristics of the pile by delaying strand yield. Cross ties 75 are optional, as are rebars 77.
In the cross sectional configuration of FIG. 8, sixteen prestressing strands 81 are arranged in a circular pattern, with four rebars 83 at the corners. A circular reinforcing outside wire spiral 85 of is used, augmented with #3 ties 87 at 12-inches on center for rebars 83. This configuration does not absorb as much energy as the configurations of FIGS. 5-7, but it is easier to construct as circular reinforcing spirals are easier to work with.
The configuration of FIG. 9 is an octogon shape chosen to represent a non square. Eighteen symmetrically arranged prestressing strands 91 are used in this arrangement with a circular spiral reinforcement wire 93. This type of section does not perform as well as FIGS. 5-8 due to loss of width at the compression face. Energy absorption capacity is less because the overall cross-sectional properties are smaller.
The TABLE below gives an energy summary of the various configurations discussed:
______________________________________Config-uration FIG. 5 FIG. 6 FIG. 7 FIG. 8 FIG. 9______________________________________Size 18 × 18 18 × 18 18 × 18 18 × 18 18 dia.(inches)Total 16 14 16 16 18StrandsTensioned 16 14 12 16 18StrandsInitial 164k 162k 160k 164kPrestressForceDesign 146k 146k 146k 146kPrestressForceDesign 450 psi 450 psi 450 psi 450 psiConcreteStressSpiral 3 inch 3 inch 3 inch 3 inch 3 inchReinforce-ment PitchConcrete Normal Normal Normal Normal Normal______________________________________
Fiber reinforcing can be added to the concrete, if desired, to improve the spalling characteristics of the concrete cover (i.e., concrete area outside the spiral reinforcement), delaying its occurrence during loading.
Epoxy coated prestressing strand and reinforcement can be used to enhance corrosion protection. However, since the fender piles are highly elastic members which spring back to a neutral position closing any flexure cracks from instantaneous berthing or other loads, such additional corrosion protection may not be warranted.
The piles used in the fendering system shown in FIGS. 1 and 2, are used with a log camel. They can also be used in a similar arrangement without a camel, in which case rub strips may be needed. Ultra high molecular weight plastic, rubber, timber, etc., rub strips can be used.
High-energy-absorbing fender piles as disclosed can be used in conjunction with commercially available foam filled fenders to form very high energy absorbing fender systems, which also provide a camel offset from a pier. In these systems the prestressed concrete piles are used as reaction piles for the foam filled fenders. Examples of these very high energy absorbing fender systems are discussed below.
As shown in FIGS. 10 and 11, only closely spaced high-energy-absorbing prestressed concrete fender piles 101 are used in conjunction with a foam filled fender 103. Chains 104 attach the foam filled fender 103 to piles 101. The prestressed concrete piles 101 are spaced approximately one foot apart. A precast concrete block whaler 105 spaces the upper ends of piles 101 from the pier 107.
In the fendering system shown in FIGS. 12 and 13, prestressed concrete piles 121 support a concrete bearing panel 123. The piles are spaced approximately 3-feet apart. Foam filled fender 125 is supported from chains 126. The concrete bearing panel 123 is a prestressed slab with steel embedment, and is attached to piles 121 with welded on brackets 127, for example. A concrete waler 128 spaces the upper ends of fender piles 121 from pier 129.
Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. | A high-energy-absorbing prestressed concrete fender pile, and fendering sem using a plurality of such piles, constructed from high-strength concrete prestressed with longitudinal tensioned strands only partially prestressed such that the longitudinal strands remian elastic to provide high remaining material strength for absorbing high energy impact prior to reaching the yield strength of the strands; the longitudinal tensioned strands are wrapped with an outer spiral wire reinforcement, and the longitudinal strands are preferably stressed to remain elastic until the concrete reches a capacity of 0.003 inch/inch compression strain. | 4 |
FIELD OF THE INVENTION
This invention relates to cable anchors, often called “clips,” for securing flexible flat cables to structural support members by means of bayonet fasteners and particularly to a device of the type described which is adjustable for receiving and securing flexible flat cables of different widths.
BACKGROUND OF THE INVENTION
It is known to anchor wiring harnesses to automotive body structures by means of clips which include a first portion which surrounds or otherwise attaches to the harness and a second portion such as a bayonet fastener which can be forced into a preformed hole in the body structure. The bayonet fastener is often called a “Christmas tree,” is made of plastic, and can take any of several forms all of which include barbs which deform to enter the hole and resist being withdrawn.
It is now becoming common to use flexible flat cables (“FFCs”) instead of more conventional bundled wires. An FFC is illustrated herein as comprising a plurality of parallel spaced apart flat conductors embedded in a flexible, plastic insulator.
The prior art shows one FFC anchor in the form of a flexible C-shaped plastic clip having an integral bayonet fastener extending from the clip base. An anchor of this design can only be used with an FFC having a width corresponding generally to the inside dimension of the C-shaped clip. Where FFCs of different widths are used, supplies of several different size anchors must be provided.
Adjustable clip-type anchors to accommodate FFCs of different widths are known. In general, such devices comprise multi-component ratchet or strap-type structures which are complex to make and use.
SUMMARY OF THE INVENTION
The present invention is a clip-type anchor for securing FFCs to support structures having one or more preformed holes by means of a bayonet fastener which can be inserted into the hole and retained by the structure after insertion. The device of the present invention accommodates FFCs of different widths, yet is simple and economical to both make and use.
In general, the present invention comprises a clip-type fastener device having first and second pivotally connected arms to form a scissors-type structure with retainer tabs at the ends. Using the scissors-action, the ends of the arms can be spread to receive the FFC and then closed to a degree to hold the FFC in place. A bayonet fastener projecting outwardly from the assembled arms is designed to be forced into a preformed hole to hold the FFC and clip in a desired location.
In the preferred embodiment, the lower arm has a central recess and the upper arm is shaped to fit into the recess such that the top surfaces of the two arms are essentially coplanar. The arms are provided with complemental bearing structures which can be snapped together to provide not only the pivotal scissors action, but also a mechanical retention which holds the two arms together. The bayonet fastener preferably extends through the center of the two arms and is held in position by a head and directional barbs on a shaft extending from the head. In this fashion, it is not necessary for the bayonet fastener to extend through the FFC and take up space which might otherwise be devoted to conductive material.
The components of the present invention are preferably formed by injection molding a suitable plastic such as Nylon to afford a measure of pliability. Means such as detents may be provided for releasably retaining the arms in one or more angular relationships to accommodate FFCs of predetermined widths.
Other features and advantages of the present invention will become apparent to those skilled in the art when the following description of the best mode contemplated for practicing the invention is read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein:
FIG. 1 is an exploded perspective view of an adjustable FFC anchor embodying the present invention;
FIG. 2 is an exploded sectional view of the components of the device of FIG. 1 ; and
FIG. 3 is a perspective view of the device of FIGS. 1 and 2 after assembly of the fastener to an FFC but before inserting the bayonet fastener into a preformed hole in an automotive body structure.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the figures, the anchor 10 of the present invention is shown to comprise a pair of injection molded plastic arms 12 and 14 which are preferably but not necessarily of equal length. The lower arm 12 has a circular central portion 16 carrying a raised cylindrical bearing structure 18 with an enlarged annular retainer ring 20 formed thereon. A central hole 22 defining an axis of rotation extends through the structure 18 to receive a barbed fastener 60 . The portion 16 has a recessed surface 24 which lies below surfaces 37 and 39 and which is planar except for the bearing structure 18 and a plurality of arcuately arranged raised detents 26 for purposes to be described.
The lower arm 12 has opposite ends 28 and 30 with raised retainer tabs 32 and 34 having oppositely extending tab arms 36 and 38 , respectively. The under surfaces of the arms 36 , 38 are spaced above planar arm surfaces 37 and 39 by the thickness of an FFC 66 (shown in FIG. 3 only), which is to be anchored by the device 10 . Through-holes 40 and 42 are provided in the tab structures 32 and 34 and arms 36 and 38 for purposes to be described.
The upper aim 14 is provided with a circular central portion 40 having through-hole 43 which is dimensional to complementary receive the bearing structure 18 of the lower arm 12 . The hole 43 is provided with an enlarged diameter annular portion 44 (shown in FIG. 2 only) to receive the annular retainer ring 20 of the lower arm 12 in a snap-lock fashion to hold the two arms 12 and 14 together in a pivotal scissors-type relationship that allows changes in the angular relationship between the two arms 12 and 24 for purposes to be described.
The under surface of the central portion 40 of the upper arm is provided with recesses 72 which cooperate with the detents 26 to permit the arms 12 and 14 to be releasably retained in each of three different angular relationships corresponding to three different FFC widths.
When assembled, the top surface 41 of the upper arm 14 is essentially coplanar with the surfaces 37 and 39 of the lower arm 12 . The height d3 of the bearing 18 is equal to the thickness of the arm 14 as shown in FIG. 2 .
The upper arm 14 also has opposite ends at which are provided retainer tabs 48 and 50 with oppositely extending fingers 52 and 54 to receive and hold an FFC as shown in FIG. 3 . Holes 56 and 58 are formed in the retainer tabs 48 and 50 and arms for purposes to be described.
The anchor 10 is completed by means of a bayonet fastener 60 having an enlarged flat head 62 and a series of unidirectional barbs 64 which relatively easily enter a hole but resist withdrawal. The device 60 is of conventional construction, is often referred to as a “Christmas tree.” The length d1 between the under surface of the head 62 and the top of the first barb 64 is approximately equal to the dimension d2 of the arm 12 as shown in FIG. 2 .
The assembled condition is shown in FIG. 3 . The arms 12 , 14 are snapped together and the fastener 60 is pushed through the center hole 22 . An FFC 66 is inserted into the anchor 10 by spreading the opposite ends of the arms 12 , 14 sufficiently to permit insertion of the FFC 66 onto the surfaces 37 , 39 and 41 and under the lateral extensions 36 , 38 , 52 and 54 of the retainer tabs. The arms 12 , 14 are squeezed together to grip the FFC 66 . The barbs 64 are thereafter forcibly inserted into and through hole 68 which is formed in the automotive body structure 70 to hold the FFC 66 and the anchor 10 in the desired position.
The width of the FFC 66 corresponds to the distance between the opposite ends of the arms 12 and 14 when in one of the positions corresponding to the locations of the detents 26 on the lower arm 12 and the recess 72 in the undersurface of the upper arm 14 as shown in FIG. 2 . Indicia may be molded into or otherwise formed on the visible upper surfaces of the arms 12 and 14 as shown in FIG. 1 to indicate to the user which FFC width is in use.
Various modifications and additions to the illustrated structures are possible. By way of example, the arm 12 may be made slightly longer than the arm 14 to cause the inwardly extending retainer tabs 38 and 54 to pass over and under one another to prevent interference. The retainer tab fingers may alternatively be angled differently, as shown, to achieve the same result. Also, by way of example, the bayonet fastener 60 may be formed integrally with the lower arm 14 . Additional bayonet fasteners may be used in connection with the holes 40 , 42 , 56 and 58 formed in the retainer tab structure at the ends of the arms 12 , 14 if additional security in the anchoring of the assembly to a body structure or the like is necessary and available.
While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law. | An adjustable clip for flexible flat cables comprising a pair of pivotally interconnected scissors arms having retainer tabs on the opposite ends and detents so that angle between the arms can be set in any of several different positions to accommodate FFCs of different widths. A bayonet fastener extends through a center hub portion so as to be forcibly inserted into a preformed hole in a support structure such as an automotive body pillar. | 5 |
BACKGROUND OF THE INVENTION
Platelet-activating factor (PAF) has recently been identified as an acetyl glyceryl ether phosphorylcholine (AGEPC), i.e., 1-O-hexadecyl/octadecyl-2-acetyl-sn-glyceryl-3-phosphorylcholine (Hanahan D. J., et al., J. Biol. Chem. 255: 5514, 1980). Even before its chemical identification, PAF had been linked to various biological activities and pathways making it one of the important mediators responsible for a variety of physiological processes including activation of coagulation of platelets, pathogenesis of immune complex deposition, smooth muscle contraction, inflammation, pain, edema as well as respiratory, cardiovascular and intravascular alterations. Since these physiological processes are in turn associated with a large group of diseases, for example, inflammatory disease, cardiovascular disorder, asthma, lung edema, and adult respiratory distress syndrome, more and more scientific investigation has been focused on the search of a PAF-antagonist or inhibitor for treating or preventing these common diseases.
The compounds of the present invention are specific PAF-antagonists. They are similar to a subclass of compounds called lignans which characteristically contain two phenylpropyl groups bonded at the β-carbon. Tetrahydrofuran (THF) lignans can exist in six different stereoisomers as shown in Scheme I. ##STR1## One of these THF lignans (+) r-2,5c-bis(3,4-dimethoxyphenyl)-3c,4t-dimethyl tetrahydrofuran, known as veraguensin, was first isolated in 1962 from the plant Octoea veraguensis. (N. S. Crosley and C. Djerassi, J. Chem. Soc., 1962, 1459).
We have prepared all the possible isomers of the tetrahydrofuran lignan analogs [T. Biftu, B. G. Hazra and R. Stevenson, J. Chem. Soc., 1978 (1147), T. Biftu, B. G. Hazra and R. Stevenson, J. Chem. Soc., 1979 (2276), C. W. Perry et al, J. Org. Chem., 1972 (4371), R. Stevenson et al, Tetrahedron, 1976 (1339), 1977 (285), F. A. Wallis et al, J. Chem. Soc., 1973 (1869) and references cited in there] with different substituents and found that the meso-cis isomer (4) is the most potent and specific PAF-antagonist.
Accordingly, it is the object of the present invention to prepare the most potent isomers of known or novel tetrahydrofuran derivatives as PAF-antagonists and use them for the treatment of various diseases including prevention of platelet aggregation, hypertension, inflammation, asthma, lung edema, adult respiratory distress syndrome, cardiovascular disorder and other related skeletal-muscular disorders.
Another object of the present invention is to develop processes for the preparation of each and every stereoisomer of the 2,5-diaryltetrahydrofuran analogs.
A further object of the present invention is to provide acceptable pharmaceutical compositions containing one or more of the tetrahydrofuran derivatives and/or analogs as the active ingredient. As PAF-antagonists, these novel compositions should be effective in the treatment of various skeletal-muscular related diseases.
Finally, it is the ultimate object of this invention to provide a method of treatment comprising the administration of a therapeutically sufficient amount of these PAF antagonists to a patient suffering from various skeletal-muscular disorders including inflammation, e.g., osteoarthritis, rheumatoid arthritis and gout, hypertension, asthma, pain, lung edema, or adult respiratory distress syndrome or cardiovascular disorder.
DETAILED DESCRIPTION OF THE INVENTION
A. Scope of the Invention
This invention relates to PAF-antagonists of the structural formula ##STR2## wherein R is: (a) hydrogen;
(b) lower alkyl of 1-6 carbon atoms, e.g. methyl, ethyl, isopropyl, butyl, pentyl or hexyl;
(c) haloloweralkyl especially C 1-6 haloalkyl, for example, trifluoromethyl;
(d) halo especially fluoro;
(e) COOH;
(f) CONR 2 R 3 wherein R 2 and R 3 independently represent C 1-6 alkyl and hydrogen;
(g) --COR 2 ;
(h) loweralkenyl especially C 1-6 alkenyl e.g., vinyl, allyl, CH 3 CH═CH--CH 2 --CH 2 , or CH 3 (CH 2 ) 3 CH═CH--;
(i) COOR° wherein R° is C 1-6 alkyl;
(j) --CH 2 OR 2 ;
(k) loweralkynyl especially C 1-6 alkynyl e.g., --C.tbd.CH;
(l) --CH 2 NR 2 R 3 ;
(m) --CH 2 SR 2 ;
(n) ═O; or
(o) --OR 2 ;
R 1 is loweralkyl; --COOH; or --COOR°; Ar and Ar 1 are the same or different from each other and are
(a) phenyl or substituted phenyl of formula ##STR3## where R 4 -R 8 independently represent H, R 2 O--, R 2 S--, R 2 SO, R 2 SO 2 --, CF 3 O--, CF 3 S--, R 2 R 3 N--, --OCH 2 CO 2 R 2 , --SO 2 NR 2 R 3 , --CO 2 R 2 , NR 2 SO 2 R 2 , COR 2 , NO 2 , or CN. For example, 3-methoxy-4-methylthiophenyl, 4-trifluoromethoxyphenyl, 3-methoxy-4-trifluoromethoxyphenyl, 3,4-dimethoxyphenyl, 3-methoxy-4-dimethylaminophenyl, 3,4,5-trimethoxyphenyl or R 4 --R 5 , R 5 --R 6 , R 6 --R 7 and R 7 --R 8 are joined together and form a bridge, for example, --OCH 2 O--, --OCH 2 CH 2 --O-- or --OCH 2 CH 2 N--;
(b) pyrryl or substituted pyrryl;
(c) furyl or substituted furyl;
(d) pyridyl or substituted pyridyl;
(e) thiophene or substituted thiophene; or
(f) naphthyl.
The compound of formula (I) can exist in the six isomers as described in Scheme I. These various isomers bear a close relationship to the PAF-antagonistic activity observed for the compounds within the scope of this invention.
Preferably, the PAF-antagonists of this invention are of structural formulae: ##STR4## or an enantiomer thereof wherein Ar and Ar 1 are as previously defined.
The most active PAF-antagonist of formula (I) as defined above is cis-3,4-dimethyl-2,5-bis-(3,4-dimethoxyphenyl)tetrahydrofuran.
B. Preparation of the Compounds Within the Scope of the Invention
The PAF-antagonists of this invention have been prepared largely by stereospecific reactions from diaroylbutanes, bromo-ferulic acid derivatives or styrene derivatives as indicated in the following four schemes. ##STR5##
C. Utility of the Compounds Within the Scope of the Invention
This invention also relates to a method of treatment for patients (or mammalian animals raised in the dairy, meat, or fur industries or as pets) suffering from disorders or diseases which can be attributed to PAF as previously described, and more specifically, a method of treatment involving the administration of the PAF-antagonists of formula (I) as the active constituents.
Accordingly, the compounds of Formula (I) can be used among other things to reduce pain and inflammation, to correct respiratory, cardiovascular, and intravascular alterations or disorders, and to regulate the activation or coagulation of platelets, the pathogenesis of immune complex deposition and smooth muscle contractions.
For the treatment of inflammation, cardiovascular disorder, asthma, or other diseases mediated by the PAF, the compounds of Formula (I) may be administered orally, topically, parenterally, by inhalation spray or rectally in dosage unit formulations containing conventional non-toxic pharmaceutically acceptable carriers, adjuvants and vehicles. The term parenteral as used herein includes subcutaneous injections, intravenous, intramuscular, intrasternal injection or infusion techniques. In addition to the treatment of warm-blooded animals such as mice, rats, horses, cattle, sheep, dogs, cats, etc., the compounds of the invention are effective in the treatment of humans.
The pharmaceutical compositions containing the active ingredient may be in a form suitable for oral use, for example, as tablets, troches, lozenges, aqueous or oily suspensions, dispersible powders or granules, emulsions, hard or soft capsules, or syrups or elixirs. Compositions intended for oral use may be prepared according to any method known to the art for the manufacture of pharmaceutical compositions and such compositions may contain one or more agents selected from the group consisting of sweetening agents, flavoring agents, coloring agents and preserving agents in order to provide pharmaceutically elegant and palatable preparations. Tablets contain the active ingredient in admixture with non-toxic pharmaceutically acceptable excipients which are suitable for the manufacture of tablets. These excipients may be for example, inert diluents, such as calcium carbonate, sodium carbonate, lactose, calcium phosphate or sodium phosphate; granulating and disintegrating agents, for example, corn starch, or alginic acid; binding agents, for example starch, gelatin or acacia, and lubricating agents, for example magnesium stearate, stearic acid or talc. The tablets may be uncoated or they may be coated by known techniques to delay disintegration and absorption in the gastrointestinal tract and thereby provide a sustained action over a longer period. For example, a time delay material such as glyceryl monostearate or glyceryl distearate may be employed. They may also be coated by the techniques described in the U.S. Pat. Nos. 4,256,108; 4,166,452; and 4,265,874 to form osmotic therapeutic tablets for control release.
Formulations for oral use may also be presented as hard gelatin capsules wherein the active ingredient is mixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate or kaolin, or as soft gelatin capsules wherein the active ingredient is mixed with water or an oil medium, for example peanut oil, liquid paraffin, or olive oil.
Aqueous suspensions contain the active materials in admixture with excipients suitable for the manufacture of aqueous suspensions. Such excipients are suspending agents, for example sodium carboxymethylcellulose, methylcellulose, hydroxypropylmethylcellulose, sodium alginate, polyvinylpyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents may be a naturally-occurring phosphatide, for example lecithin, or condensation products of an alkylene oxide with fatty acids, for example polyoxyethylene stearate, or condensation products of ethylene oxide with long chain aliphatic alcohols, for example heptadecaethyleneoxycetanol, or condensation products of ethylene oxide with partial esters derived from fatty acids and a hexitol such as polyoxyethylene sorbitol monooleate, or condensation products of ethylene oxide with partial esters derived from fatty acids and hexitol anhydrides, for example polyethylene sorbitan monooleate. The aqueous suspensions may also contain one or more preservatives, for example ethyl, or n-propyl, p-hydroxybenzoate, one or more coloring agents, one or more flavoring agents, and one or more sweetening agents, such as sucrose or saccharin.
Oily suspensions may be formulated by suspending the active ingredient in a vegetable oil, for example arachis oil, olive oil, sesame oil or coconut oil, or in a mineral oil such as liquid paraffin. The oily suspenions may contain a thickening agent, for example beeswax, hard paraffin or cetyl alcohol. Sweetening agents such as those set forth above, and flavoring agents may be added to provide a palatable oral preparation. These compositions may be preserved by the addition of an antioxidant such as ascorbic acid.
Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the active ingredient in admixture with a dispersing or wetting agent, suspending agent and one or more preservatives. Suitable dispersing or wetting agents and suspending agents are exemplified by those already mentioned above. Additional excipients, for example sweetening, flavoring and coloring agents, may also be present.
The pharmaceutical compositions of the invention may also be in the form of oil-in-water emulsions. The oily phase may be a vegetable oil, for example olive oil or arachis oil, or a mineral oil, for example liquid paraffin or mixtures of these. Suitable emulsifying agents may be naturally-occurring gums, for example gum acacia or gum tragacanth, naturally-occurring phosphatides, for example soy bean, lecithin, and esters or partial esters derived from fatty acids and hexitol anhydrides, for example sorbitan monooleate, and condensation products of the said partial esters with ethylene oxide, for example polyoxyethylene sorbitan monooleate. The emulsions may also contain sweetening and flavoring agents.
Syrups and elixirs may be formulated with sweetening agents, for example glycerol, propylene glycol, sorbitol or sucrose. Such formulations may also contain a demulcent, a preservative and flavoring and coloring agents. The pharmaceutical compositions may be in the form of a sterile injectable aqueous or oleagenous suspension. This suspension may be formulated according to the known art using those suitable dispersing or wetting agents and suspending agents which have been mentioned above. The sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenterally-acceptable diluent or solvent, for example as a solution in 1,3-butane diol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil may be employed including synthetic mono- or diglycerides. In addition, fatty acids such as oleic acid find use in the preparation of injectibles.
The compounds of Formula (I) may also be administered in the form of suppositories for rectal administration of the drug. These compositions can be prepared by mixing the drug with a suitable non-irritating excipient which is solid at ordinary temperatures but liquid at the rectal temperature and will therefore melt in the rectum to release the drug. Such materials are cocoa butter and polyethylene glycols.
For topical use, creams, ointments, jellies, solutions or suspensions, etc., containing the compounds of Formula (I) are employed.
Dosage levels of the order of from about 0.1 mg to about 140 mg per kilogram of body weight per day are useful in the treatment of the above-indicated conditions (about 5 mg to about 7 gms. per patient per day). For example, inflammation may be effectively treated by the administration of from about 0.2 to 50 mg of the compound per kilogram of body weight per day (about 20 mg to about 3.5 gms per patient per day). Preferably a dosage of from about 1 mg to about 20 mg per kilogram of body weight per day may produce good results (about 25 mg to about 1 gm per patient per day).
The amount of active ingredient that may be combined with the carrier materials to produce a single dosage form will vary depending upon the host treated and the particular mode of administration. For example, a formulation intended for the oral administration of humans may contain from 0.5 mg to 5 gm of active agent compounded with an appropriate and convenient amount of carrier material which may vary from about 5 to about 95 percent of the total composition. Dosage unit forms will generally contain between from about 1 mg to about 500 mg of an active ingredient.
It will be understood, however, that the specific dose level for any particular patient will depend upon a variety of factors including the activity of the specific compound employed, the age, body weight, general health, sex, diet, time of administration, route of administration, rate of excretion, drug combination and the severity of the particular disease undergoing therapy.
D. Bioassay Results Supporting the Utility of the Compounds of the Present Invention
It has been found that the compounds of formula (I) exhibit in vitro and in vivo antagonistic activities with respect to PAF:
A. In Vitro Assay: In vitro, they inhibit PAF-induced functions in both the cellular and tissue levels by disturbing the PAF binding to its specific receptor site. The ability of a compound of formula (I) to inhibit the PAF binding to its specific receptor binding site on rabbit platelet plasma membranes was measured by an assay recently developed by us.
The inhibition of H 3 -PAF binding to the rabbit platelet plasma membrane by a PAF-antagonist of Formula (I) was determined by a method employing isotopic labeling and filtration techniques. Generally, a series of Tris-buffered solutions of the selected antagonist at predetermined concentrations were prepared. Each of these solutions contains 1 pmole of 3 H-PAF, a known amount of the test anatgonist, and a sufficient amount of the pH 7.5 Tris-buffer solution (10 mM Tris, 0.25% bovine serum albumin, and 150 mM NaCl per ml water) to make the final volume of 1 ml. After adding into a set of test tubes each with 100 μg of the platelet plasma membrane suspension and one of the Tris-buffer solutions described above, the resulting mixture in each test tube was incubated at 0° C. for about one hour or until the reaction was complete. Two control samples, one of which (C 1 ) contains all the ingredients described above except the antagonist and the other (C 2 ) contains C 1 plus a 1000-fold excess of unlabelled PAF, were also prepared and incubated simultaneously with the test samples. After the incubation was completed, the contents of each test tube were filtered under vacuo through a Whatman GF/C fiberglass filter and the residue washed rapidly several times with a total of 20 ml cold (0°-5° C.) Tris-buffer solution. Each washed residue was then suspended in 10 ml scintillation solution (Aquasol 2, New England Nuclear, Conn.) and the radioactivity was counted in a Packard Tri-Carb 460CD Liquid Scintillation System. Defining the counts from a test sample as "Total binding with antagonist"; the counts from the control sample C 1 , as "Total binding C 1 "; and the counts from the control sample C 2 as "non-specific binding C 2 ", the percent inhibition of each test antagonist can be determined by the following equation: ##EQU1##
From our observation, compounds of formula (I) inhibit in vitro PAF-induced platelet aggregation (rabbit or human platelets); PAF-induced guinea pig peritoneal PMN (polymorphonuclear leukocytes) aggregation; PAF-induced human PMN secretion; and PAF-induced guinea pig smooth muscle concentration. They are also shown in these inhibition studies to be highly specific to PAF. For example, they do not inhibit the binding of H 1 antagonist ( 3 H-pyrilamine) to guinea pig brain membrane, nor do they inhibit the binding of a cholecystokinin (CCK) receptor based on an assay on isolated rat pancreas membrane. Furthermore, they affect no or only minute inhibition on the histamine-induced ileum contraction from guinea pigs.
Results from the In Vitro assay
The antagonistic activity of the compounds of structural formula (I) is summarized in the following table:
______________________________________ ##STR6## % inhi- iso- dose bi-R R.sup.1 Ar Ar.sup.1 mer (μm) tion______________________________________CH.sub.3 CH.sub.3 3,4-dimeth- Same (2) 10 100 oxyphenyl as Ar 3 93 1 46" " 3,4-dimeth- Same (1) 5 100 oxyphenyl as Ar 1 78 .3 62 .1 42CH.sub.3 CH.sub.3 3,4,5-trimeth- Same (1) 5 61 oxyphenyl as Ar 0.5 42" " 3,4-dimeth- Same (3) 1 68 oxyphenyl as Ar .3 37 .1 32CH.sub.3 CH.sub.3 3,4-dimeth- Same (5) 3 47 oxyphenyl as Ar .3 18" " 3,4-dimeth- Same (6) 3 75 oxyphenyl as Ar 1 16CH.sub.3 CH.sub.3 4-methoxy- Same (1) 10 47 phenyl as ArCH.sub.3 CH.sub.2 OCH.sub.3 3,4-dimeth- Same (4) 5 62 oxyphenyl as ArCH.sub.3 CH.sub.3 phenyl phenyl (1) 5 13CH.sub.3 CH.sub.3 3-methoxy- " (4) 10 49 phenyl 1 28" " 3,4-methyl- " (4) 10 45 enedioxy- 1 11 phenylCO.sub.2 Et CO.sub.2 Et 3,4-dimeth- Same (1) 1 63 oxyphenyl as ArCO.sub.2 CH.sub.3 CO.sub.2 CH.sub.3 2-chloro-4- Same (1) 1 15 hydroxy-5- as Ar methoxy- phenylCH.sub.3 CH.sub.3 2,5-dimeth- Same 10 52 oxyphenyl as ArCO.sub.2 CH.sub.3 CH.sub.3 3,4-dimeth- Same (4) 1 33 oxyphenyl as ArCOOH CH.sub.3 3,4-dimeth- Same (4) 1 18 oxyphenyl as ArCH.sub.3 CH.sub.3 3,4-dimeth- phenyl (4) 10 100 oxyphenyl 1 9CH.sub.3 CH.sub.3 3,4-dimeth- Same (4) 1 89 oxyphenyl as Ar .3 78 .1 63 .03 42" " 3,4,5-trimeth- Same (4) 20 68 oxyphenyl as Ar 5 48 1 12" " 3,4,5-trimeth- Same (2) 20 63 oxyphenyl as Ar 5 39 1 2______________________________________
B. In Vivo Assay
The specific PAF-antagonistic activities are further established by two in vivo assays (Modified procedure of Humphrey et al. Lab. Investigation, 46, 422 (1982)) following the protocols described below:
Method I: Protocol for the evaluation of the oral activity of PAF antagonists or the inhibition of PAF-induced increase of vasopermeability by PAF-antagonists
I. Animal species: 5 guinea pigs (400-500 g)
II. Material: 0.5% (w/v) aqueous methylcellulose solution sodium nembutol
2% Evans Blue solution: 2 g of Evans Blue in 100 ml of pH 7.5 Tris-Buffer solution
Tris-Buffer solution: 150 mM NaCl and 10 mM Tris/ml with pH adjusted to 7.5.
Procedure
1. Weigh the guinea pigs. Label them as control, T 1 , T 2 , T 3 and T 4 .
2. Fast the animals overnight.
3. Weigh the animals again after the fasting.
4. Ground and suspend a PAF antagonist of formula (I) with intensive sonication in 3 ml of 0.5% aqueous methylcellulose solution.
5. Administer orally to each of the animals T 1 , T 2 , T 3 and T 4 an appropriate amount (in terms of mg/kg of bodyweight) of the antagonist solution from 4., except the control animal which should receive only the 0.5% aq. methylcellulose solution.
6. Forty minutes after the oral administration, anesthetize the animals with sodium nembutol (0.75 ml/kg i.p.).
7. After 30 minutes or when the anesthetics became effective, inject intracardially to each animal 2 ml/kg body weight of the 2% Evans Blue solution.
8. Wait for 10 minutes. In the meantime, shave the backs of the guinea pigs and get ready for the PAF injection. Select two rows of 5 (a total of ten) sites on the back of each animal and designate them as sites
1a, 2a, 3a, 4a, 5a,
1b, 2b, 3b, 4b, 5b,
and inject intracutaneously, in duplicate 0.1 ml of a PAF solution in Tris-buffer or 0.1 ml of the Tris-buffer itself (control) according to the following schedule:
______________________________________Sites Solution to be injected______________________________________1a Tris-buffer1b "2a 5 × 10.sup.-9 g/ml PAF2b "3a 5 × 10.sup.-8 g/ml PAF3b "4a 5 × 10.sup.-7 g/ml PAF4b "5a 5 × 10.sup.-6 g/ml PAF5b "______________________________________
Repeat the same injection on the backs of the remaining animals.
9. Wait for 30 minutes or until the blue color developed into a steady shade on each injection site. Open the chest of each animal, extract by cardiac puncture 1 ml of blood and transfer it to a marked centrifuge tube. Centrifuge all the blood samples at about 2000 xg for 10 minutes and decant the blue tinted supernatants (plasma). Set aside these plasma samples for later spectroscopic measurements.
10. Sacrifice the animals and remove the back skin of each of them. Isolate with a 20 mm diameter steel punch the injection sites (blue spots) into individual discs of skin and dissect each of the skin discs into about 10-20 pieces.
11. Mix in a 50 ml polyethylene test tube the skin pieces from a particular injection site with a medium containing 14 ml of acetone and 6 ml of 0.5% aqueous solution of sodium sulfate. See Harada, M., et al., J. Pharm. Pharmacol. 23, 218-219 (1971) for detailed procedures. Repeat the same procedures for each individual injection site.
12. Homogenize the contents of each test tube on a polytron (Kinematica GmbH, Switzerland) with setting at 5 for 10-20 seconds.
13. In the meantime, extract a 100 μl sample of each of the plasma set aside in Step (9) with the same acetone-aqueous sodium sulfate solution used in Step (11). Set aside the resulting extracts for later determination of the Evans blue concentration in the plasma of each animal.
14. Centrifuge the skin preparations from Step (12) for 10 minutes at 750 xg and decant the supernatants for the following spectroscopic determination.
15. Measure the absorbance of each supernatant from Step (14) ("skin sample") as well as the plasma extract from Step (13) ("plasma sample") at 620 nm with a Cary 210 spectrophotometer (Varian, Palo Alto, CA). Calculate the amount of Evans blue in each skin sample in terms of the volume (μl) of the exuded blood plasma according to the following equation: ##EQU2## 16. Draw a plasma exudation curve. For example, for each of the control and the test animals.
17. Calculate the percent inhibition of PAF-induced cutaneous vascular permeability from measuring the area under the plasma exudation curve of the control animal (A C ) and those of the animals treated orally with an antagonist (A D ) according to the following equation:
______________________________________% inhibition observed from % inhibitionthe guinea pig = at x mg/kgtreated with x mg/kg dosage level ofof antagonist X. antagonist X.= .sup.A C-.sup.A D/A.sub.C × 100%= (1-.sup.A D/A.sub.C) × 100%______________________________________
where the ratio A D /A C can be determined from the weight of the paper under the plasma exudation curve of the control curve (A C ) and that under the plasma exudation curve of the treated animal T 1 (A D ).
The following table summarizes the in vivo results according to Method I.
______________________________________ ##STR7## % in- iso- dose hibi-R R.sup.1 Ar Ar.sup.1 mer (mg/kg PO) tion______________________________________CH.sub.3CH.sub.3 3,4-dimethoxy- Same (4) 50 30 phenyl as Ar______________________________________
Method II: Protocol for Assay of Activity of PAF-antagonists administered intravenously (i.v.) in inhibiting PAF-induced symptoms including increased degranulation and decreased arterial blood flow in rats
Animals: Female, Wiston rats, 190-220 g
Procedure:
1. Fast rats overnight.
2. Weigh the rats the morning after fasting.
3. Dissolve a test compound in dimethylsulfoxide (DMSO). Dilute test solution 100 fold with PAF solution in Hanks balanced salt solution.
4. Anesthetize the rat with sodium Nembutal (i.p.).
5. Cannulate surgically the left femoral vein and artery of the rat. Take blood sample from artery for basal level values.
6. Infuse through cannulated vein 0.5 ml PAF-test compound solution (0.5 nannomoles PAF per 200 g body weight of the rat). Take blood samples from the cannulated femoral artery at 1.5, 3, 5, 8, 11, 15, 20, 25 and 30 minutes after the infusion.
(a) the arterial blood flow rate: determined by measuring the time to fill a pre-calibrated 14 μl capillary tube;
(b) the vascular permeability: measured by calculating the increased hematocut which results from loss of plasma from the circulation to extra-vascular spaces.
(c) the circulatory degranulation: determined by assaying the increased plasma level of N-acetylglucosaminidase, a marker lysosomal enzyme.
7. Determine the percent change in each parameter of a blood sample at each post-PAF interval including the 30 minute interval, relative to the pre-PAF blood values.
8. Calculate the percent inhibition by the formula: ##EQU3##
Results
The inhibition of the PAF-induced responses at an i.v. dose of 50 nonnomoles of all-cis 3,4-dimethyl-2,5-bis-(3,4-dimethoxyphenyl)tetrahydrofuran are 34% for vascular permeability and 38% for degranulation. The all cis isomer of 3,4-dimethyl-2,5-bis-(3,4-dimethoxyphenyl)tetrahydrofuran at an oral dose of 50 mg/kg gave a 49% inhibition of PAF-induced degranulation.
EXAMPLE 1
r-2,t-5-Bis(3,4-dimethoxyphenyl)-c-3,t-4-dimethyl tetrahydrofuran
Step A: Preparation of Racemic-2,3-bis(3,4-dimethoxybenzoyl)butane
To 100 ml of liquid NH 3 and 100 mg FeCl 3 , 1 g of sodium added and stirred for 1 hour at -40° C. To that 7.7 g of 3,4-dimethoxypropiophene was added and stirred for 1/2 hour, 11 g of α-bromo-3,4-dimethoxypropiophenone was added and stirring continued for 11/2 hours. At this point, 11 g of ammonium chloride and 200 ml of methylene chloride was added and the temperature allowed to rise to room temperature. Filtration, evaporation and crystallization of the residue from methanol gave 14.5 g of racemic-2,3-bis(3,4-dimethoxybenzoyl)butane as a white solid. (CDCl 3 ): δ1.32 (6H, d, J=7H 2 ), 3.92 and 3.94 (6H each, s, OCH 3 ), 6.8-7.8 (6H, ArH) m.p. 141°-142° C.
Step B: Preparation of r-2,t-5-bis(3,4-dimethoxyphenyl)-c-3,t-4-dimethyltetrahydrofuran
The racemic diketone from Step A was reduced with lithium aluminum hydride and 1.0 gram of the resulting diol cyclized as follows: 1.0 g diol, 0.35 g triethylamine in 20 ml of methylenechloride was treated with 0.8 g of methane sulfonyl chloride. After 3 hours of stirring the mixture was treated with 100 ml of ether and the organic layer washed with 1N HCl 5% NaOH and distilled water respectively. Drying (Na 2 SO 4 ) and evaporation gave 0.4 g of cis,trans mixture. The major component- -2,t-5-bis-(3,4-dimethoxyphenyl)-c-3,t-4-dimethyltetrahydrofuran was recovered by multiple crystallization from hexane. NMR (CDCl 3 ): δ1.05 (6H, d, J 5.4 Hz, 2×CH 3 ), 1.8 (2H, m, 3-, 4-H), 3.88 and 3.92 (each s, 6H, 2×OCH 3 ), 4.68 (2H, d, J 8.86 Hz, 2-, 5-H), 6.8-7.1 (6H, m, Ar-H).
EXAMPLE 2
r-2,t-5-Bis(3,4-dimethoxyphenyl)-t-3,c-4-dimethyltetrahydrofuran
One gram of 2,3-bis(3,4-dimethoxyphenyl)-1,4-butanediol prepared in Step B of Example 1 above, 0.4 g 10% Pd/C in 40 ml of acetic acid was stirred over hydrogen at 40 p.s.i. Workup, followed by crystallization from hexane/ether gave 320 mg of r-2,t-5-bis(3,4-dimethoxyphenyl)-t-3,c-4-dimethyltetrahydrofuran. (m.p. 126°-7° C.). NMR (CDCl 3 ): δ1.05 (6H, d, J 6.3 Hz, 2×CH 3 ), 180 (2H, m, 3-, 4-H), 3.87 and 3.90 (each s, 6H, 2×OMe), 4.67 (2H, d, J 9.3 Hz, 2-,5-H) and 6.90-7.03 (6H, m, ArH).
EXAMPLE 3
r-2,c-5-Bis(3,4-dimethoxyphenyl)-t-3,t-4-dimethyl-tetrahydrofuran
Step A: Preparation of meso-2,3-bis(3,4-dimethoxybenzoyl)butane
One gram of racemic 2,3-bis(3,4-dimethoxybenzoyl)butane in 20 ml THF (warmed to dissolve) was treated with 50 mg of sodium methoxide in 2 ml of methanol followed by 70 ml of ether and stirred overnight. The resulting precipitate was collected by filtration, dissolved in methylene chloride and chromatographed on silica gel column with ethyl acetate-hexane (40:60). 206 mg of the front running band of meso-bis(3,4-dimethoxybenzoyl)butane (206 mg) was obtained. M.p. 188° C.
Step B: Preparation of r-2,c-5-bis(3,4-dimethoxyphenyl)-t-3,t-4-dimethyltetrahydrofuran
The meso diketone prepared in Step A (150 mg) was reduced with lithium aluminum hydride and cyclized with methanesulfonyl chloride as shown in Step B of Example 1 to give 38 mg of the major component r-2,c-5-bis(3,4-dimethoxyphenyl)-t-3,t-4-dimethyltetrahydrofuran by crystallization from hexane. NMR (CDCl 3 ): 1.02 (6H, d, J 6.4 Hz, 2×CH 3 ), 3.90 (12H, s, 4×OCH 3 ), 4.52 (2H, d, J 6.0, 2-, 5-H).
EXAMPLE 4
r-2, t-5-Bis(3,4-dimethoxyphenyl)-t-3,t-4-dimethyltetrahydrofuran
Hydrogenation of 150 mg of racemic 2,3-bis-(3,4-dimethoxyphenyl)-1,4-butanediol prepared from the meso diketone as shown in Example 3 and subsequent crystallization from hexane gave 24 mg of r-2,t-5-bis(3,4-dimethoxyphenyl)t-3,t-4-dimethyltetrahydrofuran. NMR(CDCl 3 ): δ0.64 (3H, d, J=7.0 Hz, CH 3 ), 1.03 (3H, d, J=6.0 Hz, CH 3 ), 2.36-2.56 (2H, m, 3-H and 4-H), 3.92, (6H, s, 2×OCH 3 ), 3.93 and 3.94 (3H each, s, OCH 3 ), 4.69 (1H, d, J=8.8 2-H), 5.49 (1H, d, J=4.0, 5-H), 6.8-7.0 (6H, Ar-H).
EXAMPLE 5
r-2,c-5-Bis(3,4-dimethoxyphenyl)-t-3,c-4-dimethyltetrahydrofuran
Seven grams of racemic diketone from Step A of Example 2 was dissolved in 200 ml of acetic acid, treated with 1.5 g of 10% Pd-C and hydrogenated at 40 psi overnight. Additional 1.5 g of 10% Pd-C was then added and shaking under H 2 continued for 4 hours. Filtration, evaporation and chromatography on silica gel gave 2.8 g of crystalline r-2,c-5-bis(3,4-dimethoxyphenyl)-t-3,c-4-dimethyltetrahydrofuran when eluted with ethyl acetate hexane (40:60). m.p. 121°-122° C.
EXAMPLE 6
All cis-3,4-Dimethyl-2,5-bis(3,4-dimethoxyphenyl)-tetrahydrofuran
One gram of the racemic diketone from Step A of Example 1 dissolved in 4 ml of methylene chloride was refluxed with 5 ml of 5% HCl in methanol for 15 minutes. The mixture was cooled and the crystalline crop of 3,4-dimethyl-2,5-bis(3,4-dimethoxyphenyl)-furan recovered by filtration. M.p. 169°-170° C., yield, 0.75 g. 0.3 Gram of this furan in 20 ml of acetic acid and 3 g of 10% Pd-C stirred over H 2 until 2 equivalents of hydrogen were taken up and workup followed by crystallization from etherchloroform (few drops) gave 0.22 g of the all cis-3,4-dimethyl-2,5-bis(3,4-dimethoxyphenyl)tetrahydrofuran. M.p. 130°-131° C. | Analogs of 2,5-Diaryl tetrahydrofurans which were substituted or unsubstituted at 3,4-positions were prepared.
These compounds are found to have potent and specific PAF (Platelet Activating Factor) antagonistic activities and thereby useful in the treatment of various diseases or disorders mediated by the PAF, for example, inflammation, cardiovascular disorder, asthma, lung edema, adult respiratory distress syndrome, pain, and aggregation of platelets. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority benefit of Taiwan application serial no. 88123394, filed Dec. 31 1999.
BACKGROUND OF THE INVENTION
[0002] 1. Field of Invention
[0003] The present invention relates to a method of forming a semiconductor device. More particularly, the present invention relates to a method of forming a composite silicon oxide layer over a semiconductor device.
[0004] 2. Description of Related Art
[0005] In most semiconductor devices, doped silicate glass such as borophosphosilicate glass (BPSG) is generally used as an inter-layer dielectric (ILD). This is because doped silicate glass has a low annealing temperature, thereby possessing and ability to lower the thermal budget of fabrication. However, due to the high porosity of doped silicate glass, some of the dopants inside the silicate glass can easily diffuse into neighboring layers at a moderately high temperature. Thus, semiconductor devices under the silicate glass layer may be contaminated in the back-end process, leading to reliability problems.
[0006] To prevent the contamination of a semiconductor device by dopants inside silicate glass, an isolating layer is often formed between the semiconductor device and the silicate glass layer. In other words, before doped silicate glass is deposited to form the inter-layer dielectric (ILD), undoped ozone-TEOS oxide (USG), plasma-enhanced chemical vapor deposition (PECVD) oxide, or silicon-rich oxide (SRO approximated formula SiO x , x<2) is first deposited over the semiconductor device. Among USG, PECVD oxide and silicon-rich oxide, silicon-rich oxide is the best material for preventing device contamination.
[0007] However, using silicon-rich oxide as an isolation layer has its own problems too. In depositing silicon-rich oxide, hydrogen molecules are often produced. These hydrogen molecules are often retained inside the silicon-rich oxide after the reaction, leading to a possible contamination of nearby semiconductor devices. Consequently, hot carrier degradation, current leakage and resistivity change of semiconductor devices occur more frequently.
SUMMARY OF THE INVENTION
[0008] Accordingly, one object of the present invention is to provide a method of forming a composite silicon oxide layer over a semiconductor device so that hot carrier degradation, current leakage and resistivity change of the device are minimized.
[0009] To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention provides a method of forming a composite silicon oxide layer. The composite silicon oxide layer is formed between the semiconductor device and a doped silicate glass layer. This composite silicon oxide layer is composed of two silicon oxide layers, each having a different silicon-to-oxygen ratio. The silicon oxide layer that contacts the doped silicate glass layer is a silicon-rich oxide layer (SiO x , x<2), while the other silicon oxide layer that contacts the semiconductor device is a silicon dioxide (SiO 2 ) layer.
[0010] In addition, the two silicon oxide layers having different silicon/oxygen ratios are formed in the same plasma deposition step. The plasma deposition is carried out using, for example, SiH 4 —N 2 O plasma. The method of controlling the silicon/oxygen ratios in each of the two silicon oxide layers includes changing the ratio of SiH 4 to N 2 O in the SiH 4 —N 2 O plasma.
[0011] In this invention, since the silicon-rich oxide layer of the composite layer is in contact with the doped silicate glass layer, dopants inside the doped silicate glass layer are prevented from diffusing into and contaminating the semiconductor device underneath. On the other hand, since the silicon dioxide layer in the composite layer is attached to the semiconductor device, any residual hydrogen molecules in the silicon-rich oxide is prevented from crossing into the underlying semiconductor device. Therefore, resistivity of the semiconductor device can be maintained and leakage current from the semiconductor device can be minimized.
[0012] Furthermore, since the two silicon oxide layers are formed by plasma deposition reactions in the same plasma chemical vapor deposition chamber, there is no additional complication other than that of forming a single silicon-rich oxide layer.
[0013] In brief, the composite silicon oxide layer of this invention is capable of preventing dopants in the doped silicate glass layer as well as residual hydrogen molecules in the silicon-rich oxide layer from contaminating the semiconductor device. Hence, quality of the semiconductor can be maintained. Moreover, since the two silicon oxide layers are formed in the same reaction chamber, no additional steps need to be taken.
[0014] It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,
[0016] [0016]FIG. 1 is a flow chart showing the steps for forming the composite silicon oxide layer over a semiconductor device according to this invention;
[0017] [0017]FIG. 2 is a schematic cross-sectional view showing a composite silicon oxide layer over an N-type metal oxide semiconductor (NMOS) structure according to one preferred embodiment of this invention;
[0018] [0018]FIG. 3 is a schematic cross-sectional view showing a composite silicon oxide layer over a P-type sheet resistor according to one preferred embodiment of this invention;
[0019] [0019]FIG. 4 is a three-dimensional diagram showing thickness variation of the silicon dioxide layer and refractive index variation (silicon/oxygen variation) of the silicon-rich oxide layer versus yield in leakage current test for an NMOS device with a composite silicon oxide layer thereon according to this invention; and
[0020] [0020]FIG. 5 is a bar chart showing the effect of refractive index variation (silicon/oxygen variation) of the silicon-rich oxide layer on resistivity for a P-type resistor with a composite silicon oxide layer thereon according to this invention.
[0021] Note that the silicon/oxygen ratio in the silicon-rich oxide layer is indicated by the refractive index (RI). In other words the higher the silicon/oxygen ratio, the higher the refractive index will be.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
[0023] [0023]FIG. 1 is a flow chart showing the steps for forming the composite silicon oxide layer over a semiconductor device according to this invention. First, as shown in FIG. 1, a substrate having a device such as an NMOS transistor, a PMOS transistor, or a P-type sheet resistor therein is provided. Steps for forming the composite silicon oxide layer are next conducted. In other words, a silicon dioxide layer is first formed over the substrate, and then a silicon-rich oxide layer is formed over the silicon dioxide layer by changing the deposition reaction conditions. Finally, a doped silicate glass layer that functions as an inter-layer dielectric is formed over the silicon-rich oxide layer. In FIG. 1, the refractive index (RI) is an indication of silicon/oxygen ratio inside the silicon oxide layers. For instance, the silicon dioxide layer has a refractive index of 1.46 while the silicon-rich oxide (SiO x , x<2) layer has a refractive index greater than 1.46. Moreover, the greater the value of the refractive index, the higher the ratio of silicon to oxygen will be. In the embodiment of this invention, refractive index of the silicon-rich oxide layer is between about 1.50 and 1.55.
[0024] In this invention, the silicon dioxide layer and the silicon-rich oxide layer of the composite silicon oxide layer are formed in the same plasma deposition step. The plasma used in the plasma deposition is preferably SiH 4 —N 2 O plasma. By varying the ratio between SiH 4 and N 2 O in the SiH 4 —N 2 O plasma, the silicon dioxide layer and the silicon-rich oxide layer with a pre-defined silicon/oxygen ratio can be formed in sequence over the semiconductor device in the same step. For example, the silicon dioxide layer is formed in a plasma chamber by setting the flow rate of SiH 4 to 125 cm 3 /min and the flow rate of N 2 O to 2000 cm 3 /min. On the other hand, to form the silicon-rich oxide layer having a refractive index of 1.52, the flow rate of SiH 4 is set to 150 cm 3 /min while the flow rate of N 2 O is set to 680 cm 3 /min.
[0025] In the following description, a composite silicon oxide layer is formed over an NMOS transistor and a P-type sheet resistor, respectively, to illustrate some applications (in FIGS. 2 and 3) of this invention. The advantages of this invention are illustrated through some testing figures (in FIGS. 4 and 5).
[0026] [0026]FIG. 2 is a schematic cross-sectional view showing a composite silicon oxide layer over an N-type metal oxide semiconductor (NMOS) structure according to one preferred embodiment of this invention. As shown in FIG. 2, the NMOS transistor 200 includes a P-type silicon substrate 210 , a polysilicon gate 220 and source/drain regions 230 . A silicon dioxide layer 240 , a silicon-rich oxide layer 250 and a doped silicate glass layer 260 (inter-layer dielectric) are sequentially formed over the NMOS transistor 200 . The silicon dioxide layer 240 and the silicon-rich oxide layer 250 together form the composite silicon oxide layer of this invention.
[0027] [0027]FIG. 3 is a schematic cross-sectional view showing a composite silicon oxide layer over a P-type sheet resistor according to one preferred embodiment of this invention. As shown in FIG. 3, the P-type sheet resistor 300 includes an N-type well 310 and a P-type diffusion region 320 . A silicon dioxide layer 340 , a silicon-rich oxide layer 350 and a doped silicate glass layer 360 (inter-layer dielectric) are sequentially formed over the P-type diffusion region 320 . The silicon dioxide layer 340 and the silicon-rich oxide layer 350 together form the composite silicon oxide layer of this invention.
[0028] In the examples of FIGS. 2 and 3, the silicon-rich oxide layers 250 and 350 have a thickness of about 1000 Å to 2000 Å while the silicon dioxide layers 240 and 340 have a thickness of about 200 Å to 1000 Å.
[0029] [0029]FIG. 4 is a three-dimensional diagram showing thickness variation of the silicon dioxide layer 240 and refractive index variation (silicon/oxygen variation) of the silicon-rich oxide layer 250 versus yield in leakage current test for the NMOS device 200 with a composite silicon oxide layer thereon according to this invention. As shown in FIG. 4, when the refractive index of the silicon-rich oxide layer 250 is fixed (at a fixed silicon/oxide ratio), a greater thickness of the silicon dioxide layer 240 means a smaller leakage current. When the refractive index of the silicon-rich oxide layer 250 is at the maximum value of 1.55, leakage current is considerably lowered by a silicon dioxide layer 240 that is just 500 Å thick. In other words, current leaks are effectively stopped by the silicon dioxide layer 240 in the composite oxide layer of this invention.
[0030] [0030]FIG. 5 is a bar chart showing the effect of refractive index variation (silicon/oxygen variation) of the silicon-rich oxide layer 350 on resistivity for a P-type resistor 300 with a composite silicon oxide layer thereon according to this invention. As shown in FIG. 5, the effect of the composite silicon oxide layer on the resistance of the P-type sheet resistor 300 is smaller (that is, error range of resistance value is smaller) compared with a P-type sheet resistor protected by just one silicon-rich oxide layer. In other words, the composite silicon oxide layer is better able to stabilize the resistance of the P-type sheet resistor 300 . The error range of the resistor is lowered considerably. especially when the refractive index (or silicon/oxygen ratio) of the silicon-rich oxide layer is between about 1.52 and 1.55.
[0031] In summary, since the silicon-rich oxide layer of the composite layer is in contact with the doped silicate glass layer, dopants inside the doped silicate glass layer are prevented from diffusing into and contaminating the semiconductor device underneath. On the other hand, since the silicon dioxide layer in the composite layer is attached to the semiconductor device, any residual hydrogen molecules in the silicon-rich oxide layer is prevented from crossing into the underlying semiconductor device. Therefore, resistivity of the semiconductor device can be stabilized and leakage current from the semiconductor device can be minimized. Furthermore, since the two silicon oxide layers are formed by plasma deposition in the same plasma chemical vapor deposition chamber, there is no additional complication than that of forming a single silicon-rich oxide layer.
[0032] It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents. | A method of forming a composite silicon oxide layer over a semiconductor device. The composite silicon oxide layer is formed between the semiconductor device and a doped silicate glass layer. The composite silicon oxide layer comprises two silicon oxide layers, each having a different silicon/oxide composition. The oxygen-rich oxide layer or silicon dioxide layer is formed directly above the semiconductor device, and the silicon-rich oxide layer is formed above the silicon dioxide layer next to the doped silicate glass layer. Both the silicon dioxide layer and the silicon-rich oxide layer are formed in the same plasma deposition chamber. | 7 |
RELATED US APPLICATIONS
This is a continuation-in-part of Ser. No. 10/452,421, filed Jun. 2, 2003, Pub No. U.S. 2003/0211198 A1, Pub Date Nov. 13, 2003, now abandoned which is a continuation-in-part of Ser. No. 09/943,152, filed Aug. 30, 2001, now abandoned.
FIELD OF THE INVENTION
This invention relates generally to the art of injection molding apparatus and, more particularly, to an improvement in injection molding apparatus check valve assemblies as applied to restrict back-flow of a plasticized polymeric material during an injection stroke of the apparatus. The specific improvement comprises adhesively attaching abrasion-resistant disks within recesses extending into friction wear surfaces of an injection molding check valve. surfaces.
BACKGROUND OF THE INVENTION
Injection molding of plasticized polymeric materials including plastic and/or elastomeric type materials has been known and practiced for a long time. These type of apparatus are conventionally associated with various molding machines which are adapted for receiving the plasticized polymer and forming it into many useful parts and/or products.
Injection molding apparatus of the type alluded to are generally comprised of a feed-screw or auger member rotatably carried within a substantially cylindrical barrel, the screw effectively moving and plasticizing the polymeric material throughout the length of the barrel towards an exit end where it is forcefully injected into a molding machine for forming and curing of the material into the desired end product. At an exit end of the feed-screw there is conventionally mounted a check valve assembly which is designed to meter out the proper amount of plasticized material by a pressure reactive motion of the valve to effectively shut off the supply of material and to thereafter force the desired volume of plasticized polymer out of an exit nozzle and into the mold cavity of the molding machine.
Many improvements in this art have been suggested and applied to the injection molding apparatus and these, to an improved configuration of the feed-screw member and/or to the check valve assembly to gain greater efficiency in the injection operation by shortening the injection cycle period. Obviously, a shorter cycle period of the injection molding apparatus will also result in an increase in the number of parts which may be produced inasmuch as the molding machines associated therewith may also be configured to accept and form more individual parts.
These improvements in the injection molding apparatus have fairly coincided with advances in the polymer science and technology which has provided improved material chemistry. The improvements, however, have not been without problems as there is now a noticeable increase in wear of the various member elements which comprise the injection molding apparatus. For example, it has been determined that no natural lubricants are available in many of the polymeric materials and this lack of lubrication increases the friction and therefore also the heat generated in plasticizing and injecting the material. Furthermore, it is not possible to add a lubricating material to the process as these tend to contaminate the polymer and this affects the quality of the finished molded product.
In view of the above, friction wear of critical working elements of the injection molding apparatus is a major and continuing problem in the industry as these must be replaced at regular and, in some instances, very short intervals.
It is, of course, generally well-known and recognized by those knowledgeable in this art that the various working elements of the injection molding apparatus are comprised of very expensive tool and/or alloy steels, and this, because of the exceptional wear that these elements experience in this type of process. Thus, the very short service lifetimes of these elements will naturally also effect an increase in the cost of the molded parts being produced.
The following prior art patents fairly represent what has been done in attempts to improve the injection molding apparatus: U.S. Pat. Nos. 3,698,694; 4,106,113; 4,105,147; 4,472,058; and 4,988,281. Further, U.S. Pat. No. 3,209,408 addresses the friction wear problem by providing a ball-bearing configured check valve assembly. Such type ball-bearing configurations-are also evident in some of the above-listed prior art patents. In addition, U.S. Pat. No. 4,530,605 attempts to alleviate part of this problem by providing a rapid take-down configuration for a check valve assembly such that when worn parts need to be replaced this may be done quickly and efficiently with the least amount of down-time. From this it should be apparent that the friction wear problem of critical elements of an injection molding apparatus still exists and this, irrespective of the various advances in the art.
Our prior U.S. Pat. No. 5,167,971 helped to solve the problem by reducing the amount of wear on the various wear surfaces of the valve assembly, and in our prior application Ser. No. 09/943,152, abrasion resistant ceramic layers were adhesively attached to the wear surfaces, however further modifications were found to be needed to deal with the differential in expansion and contraction between the ceramic layers and the metal in order to achieve better adhesion between the ceramic and metal.
Better adhesion of the ceramic material to the metal has been achieved by this present invention by providing a plurality of ceramic disks substantially covering the wear surfaces of the valve assembly to provide improved abrasion-resistance and which are of a size that is not significantly affected by the differences in coefficient of expansion and contraction of the ceramic and metal materials. An improved adhesion of the ceramic material to the metal wear surfaces is also accomplished by attaching the ceramic disks within cylindrical recesses extending into the wear surfaces. This provides greater surface contact between the disks and the wear surfaces.
It has also been found that the adhesion of the ceramic disks within the recesses has been greatly increased by providing notched portions or annular grooves extending around the circumference of the disks and providing and interlocking effect between the grooves and the adhesive flowing into the grooves and curing therein to form radially inwardly extending ribs when cured.
It is, therefore, in accordance with a primary aspect of the present invention an object to provide an improved check valve assembly for an injection molding apparatus wherein the service lifetimes of the various working elements is increased such that many more molded products may be produced before it becomes necessary to replace the working elements of the apparatus.
In accordance with another aspect of the invention it is an object to provide an improved injection molding apparatus check valve assembly which may be made from less expensive base metal and/or tool steel than now applied for these type elements while also providing an operational service life which is greatly for extended over what is available with presently made check valve assemblies.
An even further object of this invention is to provide a plurality of ceramic abrasion-resistant layer ceramic disks substantially covering the wear surfaces which disks may be adhered to the metal wear surfaces without the use of heat being applied to the metal surfaces which might affect the base metal hardness.
Another object of the invention is to provide a plurality of abrasion-resistant ceramic disks having lower frictional heat due to density of the disks.
An even further object of the invention is to provide a plurality of abrasion-resistant ceramic disks which may be adhesively attached to any hardness of metal.
Another object of the invention is to provide a plurality of abrasion-resistant ceramic disks which may be adhesively attached to stainless steel and corrosion resistant high nickel alloys.
SUMMARY OF THE INVENTION
This invention is a check valve assembly for an injection molding apparatus having a rotatable and axially translatable feed-screw within a barrel bore and adapted for moving a polymeric material through the valve assembly towards an exit chamber of the apparatus, the check valve assembly characterized by: a valve body member attached to the forward end of the feed-screw and moveable with the feed-screw, said body member having at least one valve seat surface thereon, an axially slidable member mounted on the body member for limited axial movement thereon, said slidable member having; at least one valve seat surface which frictionally engages a corresponding valve seat surface on the body member, and a circumferential surface at its outside diameter which frictionally engages the inner surface of the barrel bore, the improvement comprising a plurality of cylindrical recesses extending into at least part of the valve seat wear surfaces, said recesses being filled with abrasion-resistant ceramic disks securely attached therein, said disks effectively reducing frictional wear between coacting frictionally engaging surfaces and between the surfaces and the plasticized material as it is moved through the check valve assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
These an other advantages and features of the invention will hereafter appear for purposes of illustration, but not of limitation, in the accompanying drawings, in which like-reference numerals are used to identify like elements and wherein:
FIG. 1 is a side elevational view, in cross-section and with various parts broken away, illustrating a state-of-the-art injection molding apparatus as may benefit from the concepts taught by the present invention;
FIG. 2 is a greatly enlarged elevational view, in cross-section, of but a portion of the injection molding apparatus shown in FIG. 1 illustrating the application of the present invention;
FIG. 3 is a greatly enlarged elevational view, in cross-section similar to FIG. 2 but showing a slightly different modification of the invention;
FIG. 4 is a rear end view of a conically shaped tip end of an injection molding apparatus showing a valve seat surface;
FIG. 5 is a front end view of a check ring of an injection molding apparatus, showing a valve seat surface;
FIG. 6 is an enlarged perspective view of an abrasion resistant ceramic disk having an annular groove extending around its periphery;
FIG. 7 is an enlarged perspective view similar to FIG. but having two annular rings extending around the periphery of an abrasion resistant ceramic disk;
FIG. 8 is an enlarged fragmentary cross sectional view through a wear surface of the injection molding apparatus shown in FIG. 2 , having a ceramic disk similar to that shown in FIG. 6 ; and
FIG. 9 is an enlarged fragmentary cross sectional view through a wear surface of the injection molding apparatus shown in FIG. 2 , having a ceramic disk similar to that shown in FIG. 7 .
DETAILED DESCRIPTION OF THE INVENTION
In the drawing, FIG. 1 illustrates an injection molding apparatus generally indicated by reference numeral 10 . The apparatus 10 conventionally comprises a substantially cylindrical barrel 12 having a specific longitudinal length and it will be recognized that only the exit or output end of the barrel 12 is shown in the drawing. Of course, and as is well-known and understood in this art, an input end (not shown) will include a hopper mechanism for feeding various type of consideration of the present invention. The barrel 12 may be characterized by a bore 14 centered on a longitudinal axis as indicated by the line Ax-Ax in the drawing. The exit end of the barrel 12 is generally indicated by reference numeral 16 and it may comprise an end cap member 18 which is affixed at 20 to the end of the barrel 12 by any of various well-known methods and/or techniques. The end cap 18 is characterized by a through-bore 22 , a partial portion of which is conically shaped as at 22 a and it connects into an exit bore 24 of a nozzle tip 26 . The nozzle tip 26 is adapted for a mating relationship of the injection molding apparatus 10 to a molding machine (not shown) in the well-known and understood manner of such apparatus.
A feed-screw member 30 is mounted co-axially within the bore 14 of the extruder barrel 12 and it is characterized by a helically oriented thread 32 having a land portion 34 exhibiting an outside diameter D 1 which is substantially but not exactly equal to the inside diameter D 2 of the bore 14 . A slight frictional engagement between the two is evident when the feed-screw 30 is rotated within the barrel bore 14 . The feed-screw 30 has a body 36 exhibiting an outside diameter D 3 which is less than the outside diameter D 1 of the thread 32 by a specific amount and it may be appreciated that a rotation of the feed-screw 30 will effect a movement of any material caught between the outside surface of the feed-screw body 36 and the inside surface of the bore 14 toward the exit end 16 of the apparatus 10 .
The feed-screw member 30 has an extruder check valve assembly 40 mounted to its forward end and valves of this type may comprise two or more separate but co-operating parts or elements as evidenced in various of the prior art patents. The particular check valve 40 shown in the drawing comprises a valve body 42 characterized by a conically-shaped tip end 44 and a shank end 46 which has a plurality of threads 48 for a portion of its length. The valve body 42 is affixed to the forward end of the feed-screw 30 by way of the shank end 46 being threadably engaged within a threaded bore 38 at the end of the feed-screw 30 . The conically-shaped tip end 44 is shaped to mate with the conically-shaped bore 22 a such that any material within the forward portion of the barrel bore 14 will be forceably directed into the exit bores 22 and 24 and out of the exit orifice 28 by an axial movement of the feed-screw 30 into the end cap member 18 . It is, of course, well-recognized and understood that the feed-screw 30 is connected to a power source (not shown) which controls its rotational and/or axial motion and the particular power means, therefore, is not important to the scope of the present invention.
The shank end 46 of the valve body 42 has a shoulder 50 formed between the smaller diameter threaded portion 48 and a larger diameter valve passage portion 52 , the shoulder 50 providing an axial stop for a valve seat ring 54 carried on the smaller diameter portion 48 . The valve seat ring 54 has a forwardly-facing valve seat bearing surface 56 and it is further characterized by an outside diameter which is substantially equal to the diameter D 3 of the feed-screw body 36 . As clearly evident in the drawing, the valve seat ring 54 is maintained in position between the shoulder 50 and the terminal end of the feed-screw 30 when the valve body 42 is threadably engaged within the bore 38 in the end of the feed-screw.
The valve seat ring 54 comprises the rearward valve seat surface 56 of the check valve assembly 40 while a forward valve seat surface 58 is formed on a backside annular surface of the conically-shaped tip end 44 . The forward valve seat 58 has a number of axially oriented flute passages 60 passing therethrough and the purpose of these will become apparent as this description proceeds.
The check valve assembly 40 further comprises a check ring member 70 which is mounted about the shank portion 52 of the shank end 46 and it is movable in the axial direction between the rearward valve seat 56 and the forward valve seat 58 . The check ring 70 is further characterized by frustoconical valve seat surfaces 72 and 74 , the valve seat surface 72 being in a position to sealingly engage the rearward valve seat 56 of the valve seat ring 54 while the valve seat surface 74 is in a position to sealingly engage the forward valve seat surface 58 on the valve body 42 . The valve seat surfaces 56 , 58 , 72 , and 74 are obviously mating surfaces and these may be disposed at an angle within the range of 0°-30° with respect to a radially oriented plane which is positioned orthogonally on the Ax axis.
Further with respect to the check ring member 70 , it has an outside diameter surface 75 , which is substantially but not exactly equal to the inside diameter D 2 of the bore 14 . While a sealing type engagement is effected as between the check ring 70 and the bore wall 14 such that material moving through the bore may not pass therebetween, the check ring is movable in the axial direction so as to be alternately engageable with either of the forward valve seat surface 58 or the rearward valve seat surface 56 . The check ring 70 also has an inside bore diameter which is larger than the outside diameter of the the forward portion 52 of the shank end 46 about which it is mounted. In this configuration, an annular passage indicated at reference numeral 76 is evident and it provides a pass-through for polymeric material when the check valve the check valve assembly 40 is in the “valve-opened” position as shown in the drawing.
In the operation of the injection molding apparatus 10 , it will be recognized that a material distribution chamber generally indicated by reference numeral 80 may be establish ed between the tip end 44 of the check valve assembly 40 and the conically-shaped bore 22 a of the end cap member 18 . When the volume of the distribution chamber 80 is established for a particular molded part, the feeds crew 30 is maintained in its axial position within the barrel bore 14 but it is rotated about the Ax axis. This rotation of the feed-screw 30 effectively moves polymeric material being fed into the barrel 12 longitudinally down the bore 14 towards the exit end 16 . The movement of material effectively also moves the check ring 70 into axial engagement with the forward valve seat surface 58 as shown in the drawing. Polymeric material is thus able to move through the check valve assembly 40 by way of the open annular passage 76 and the axial flute passages 60 and then into the distribution chamber 80 . As the distribution chamber 80 is filled, an injection stroke of the feed-screw 30 causes the check ring 70 to move into axial engagement with the rearward valve seat surface 56 of the valve seat ring 54 . Initiation of this powerful injection stroke of the feedscrew 30 in the axially forward direction forces any material within the chamber 80 out of the exit orifice 28 and into a relatively positioned molding chamber (not shown).
From the foregoing description of the injection molding apparatus 10 , it must be appreciated that the relative motions as between the various member elements of the apparatus generates heat which also increases the friction component as between the members. This is further aggravated by heat being generated within the polymeric material as it is processed through the apparatus and by a friction component which exists as between the material itself as it passes over the various member element surfaces. It will, of course, be recognized that the operational service life of the various members will be shortened by the amount of wear of critical surfaces and especially the valve seat surfaces of the check valve assembly 40 which actually govern the operation of the injection molding process. Referring now to FIG. 2 of the drawings, a greatly enlarged elevational view of a portion of the apparatus 10 of FIG. 1 is illustrated. In this figure, like-reference numerals are used to designate like elements of FIG. 1 and the primed reference numerals are used to indicate the improved elements of the apparatus in accordance with the concepts of the present invention.
The showing of FIG. 2 is of the forward end of the feed-screw member 30 which carries the check valve assembly 40 in axial position at it forward end. The check valve assembly 40 ′ shown in FIG. 2 is an improved design wherein various of the element surfaces which exhibit exceptional wear and which are critical to the operation of the injection molding apparatus are substantially covered with a plurality of substantially abrasion-resistant ceramic disks 59 ′ securely attached within a plurality of cylindrical recesses 61 ′ in at least the flat annular wear surfaces 58 ′ and 74 ′, which disks, dramatically increases the operational service life of the check valve assembly 40 ′. When using the disks 59 ′, the flat annular surfaces 58 ′ and 74 ′ are preferable to the frustoconical surfaces 58 and 74 shown in FIG. 1 .
In FIGS. 4 and 5 , the disks 59 ′ positioned in the valve seat surfaces 58 ′ and 74 ′ are shown in their relative locations around the valve seats 58 ′ and 74 ′ respectively.
To produce the disks 59 ′, ceramic materials taken from the group comprising the ceramic oxides may be fired to the desired hardness and formed into a plurality of disks 59 ′ of a size to cover a substantial portion of the wear surface and adhesively attached to the wear surface such as shown in FIG. 2 by attaching them in recesses 61 ′.
After the disks 59 are attached to the selected wear surfaces of the valve parts, the disks and wear surface can then be machined to the desired final gauge thickness so that the outer surface of the disks are flush with the wear surface it is mounted in. For such ceramic disks, a final gage thickness of between ⅛ and ¼ inches, (3.175 and 6.350 mm) is preferable.
One of the preferred ceramic materials which provides an excellent abrasion resistance is a high alumina aluminum oxide. Another ceramic oxide which is also a good choice for abrasion resistance is zirconia and in particular Cerium Oxide Partially Stabilized Tetragonal Zirconia Polycrystal.
The ceramic oxides are considered preferable for use on the forward valve seat surface 58 ′ on the back side of the conically shaped tip end 44 .
The ceramic disks 59 ′ described previously, are attached to the wear surfaces of the valve by a high temperature adhesive having the required physical properties to withstand the environment in which it is to used within the valve assembly.
One of the preferred ceramic materials which provides an excellent abrasion resistance is a high alumina aluminum oxide. Another ceramic oxide which is also a good choice for abrasion resistance is zirconia and in particular Cerium Oxide Partially Stabilized Tetragonal Zirconia Polycrystal.
The ceramic oxides are considered preferable for use on the forward valve seat surface 58 ′ on the back side of the conically shaped tip end 44 .
With regard to wear surfaces other than 58 ′ and 74 ′, a bonded metallic coating shown in stippled areas is applied to the valve seat ring surface at 56 ′, the check ring valve seat surface 72 ′, and the check ring outside diameter surface 75 ′.
The bonded coating preferably comprises a metal and/or metal alloy exhibiting a density of at least gm/cm 3 at 20°. These may be spray-coated on the desired surface by a technique and/or process know in the metallurgical art as “High Velocity Oxygen Fuel Coating”, which is carried out using specific type equipment at over 1927° C.
The bonded coating material is preferably applied to a gage thickness of not more that 0.030 inch, (0.762 mm) after which the surface is machine-ground to a gauge thickness within the range of 0.005-0.025 inches, (0.127-0.635 mm). Preferably after the grinding operation, the coating material exhibits a gauge thickness of at least 0.006 inch, (0.152 mm). Metal and/or metal alloys of the type alluded to are preferably a mixture of tungsten carbide, cobalt and other elements selected from the group of iron, carbon, nickel and chromium.
In addition to metal and/or metal alloy bonded coatings, it will be recognized that various types of ceramic materials may provide the desired abrasion resistance and these may also applied in a manner similar to the valve seat and other frictionally engaging wear surfaces.
This invention, therefore, is not limited to a particular ceramic, metal and/or metal alloy layer but, in the broadest sense covers any high abrasion-resistant material which may be adhesively attached or if carbide coating are used, they are attached to the wear surfaces by spray coating by the High Velocity Oxygen Fuel Coating process.
Finally, it will also be recognized that when such abrasion resistant coatings are used, the underlying base metal may comprise a less expensive metal and/or metal alloy than presently being used for these parts. For example, the very expensive tool and alloy steels presently being used for the valve seat ring 54 and the check ring 70 may be replaced with a number 4150 steel which costs ninety-five percent less. Obviously, a great savings in materials may be realized by the application of the present invention.
FIG. 3 shows a different embodiment from that shown in FIG. 2 in which similar parts are shown with a double prime (″) instead of a single prime (′) as used in FIG. 2 . In FIG. 3 , the rear end of the conical shaped tip end 44 ′″ is divided into two parts with a bead seat ring 45 positioned against the rear end of the tip end 44 ″. A valve seat ring 54 ″ has a forward tubular extension 55 which bears against a rear annular surface 45 a on the ring 45 and holds it in position. All the remainder of the wear surfaces 56 ″, 58 ″, 72 ″, 74 ″ and 75 ″ are similar to those similar numbers described in FIG. 2 . Except for the addition of ring 45 and tubular extension 55 , all the rest of the parts of the assembly shown in FIG. 3 are the same as in FIG. 2 and the disk material of ceramic oxide or coating carbide material can be used. It should also be noted that the wear surfaces 58 ″ and 74 ″ are flat annular surfaces similar to the surfaces 58 ′ and 74 ′ in FIG. 2 .
FIGS. 6-9 show a modified version of the abrasion resistant ceramic discs 59 ′ and 59 ″ shown in FIGS. 2 and 3 . FIG. 6 shows a disk 59 a with a single annular groove 78 extending around the periphery of the disk and FIG. 7 shows a disk 59 b with a pair of annular grooves 80 extending around the periphery of the disk.
FIG. 8 shows the disk 59 a adhesively attached in a recess 61 ′ of a valve seat 58 ′.
Likewise FIG. 9 shows the disk 59 b adhesively attached in a recess 61 ′ of a valve seat 58 ′. A high temperature adhesive is used to fasten the disks 59 a and 59 b in the recesses 61 . The purpose of the annular grooves 78 and 80 is to provide a space into which the adhesive can flow and provide and interlocking relationship between the adhesive and the periphery of the disk when the adhesive cures and thereby fasten the disks 59 a or 59 b more securely in the recesses 61 .
It will be recognized that various shapes of notches or grooves can be placed in the periphery of the ceramic disks to improve the retention of the disk by the adhesive.
While certain representative embodiments and details have been shown for the purpose of illustrating the invention, it will be apparent to those skilled in this art that various changes and/or modifications may be made therein without departing from the spirit or scope of the invention. | An injection molding apparatus which includes a check valve assembly mounted at the forward end of a feed-screw, the valve assembly having forward and rearward valve seat surfaces which co-act in a first position to allow a plasticized polymeric material to enter and flow through the valve into an injection chamber and which co-act in a second position to stop any additional material from entering the valve assembly. The second valve position is effected by a feed-screw injection stroke which generates a back pressure to close the valve, the back pressure moving a check ring of the valve assembly into a position to block entry into the valve. Part of the valve seat surfaces are covered with a plurality of ceramic disks and other valve seat surfaces are covered with a metal alloy which effectively increases the abrasion resistance of the valve seat surfaces and thus also increases the wear service life of the check valve assembly. Other wear surfaces of the valve assembly may also be coated for abrasion resistance. | 1 |
This is a division of application Ser. No. 07/509,950, filed Apr, 16, 1990 now U.S. Pat. No. 5,112,947.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to novel peptides having a hoottopic effect and being useful as medicines, particularly as antidementia agents.
2. Description of Prior Art
Vasopressin has been previously known as a compound having a hoottopic effect, i.e., intelligence developing effect. Recently, it has been reported that peptides seemingly corresponding to a vasopressin fragment, for example, those having the following formulae: ##STR4## have such a nootropic effect as that of vasopressin in Science, 221, pp.1310-1312 (1983) and Brain Research, 371, 17(1986).
Further, there is also reported that a peptide having the following formula: ##STR5## has a nootropic effect in Japanese Patent Provisional Publication No.59(1984)-93036.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide new peptide derivatives which are superior in the nootropic effect to the known vasopressin as well as to the known peptides corresponding to vasopressin fragments.
The present invention provides a novel peptide having the formula (I): ##STR6## wherein A and B represent the amino acids; wherein in the case that A is D- or L-Pro, B is Hat or Cit;
in the case that A is D-Pro, B is D-Arg; and
in the case that B is D- or L-Arg, A is Sar, Pip, Aze or Arg,
its functional derivative, and a pharmaceutically acceptable salt thereof.
Further, the invention provides an antidementia agent containing, as a pharmaceutically active component, an effective amount of the peptide having the above formula (I), its functional derivative or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier or diluent.
The invention also provides a novel peptide having the formula (II):
Asn-A-L-(D-)Pro-Arg-(Gly)n (II)
wherein A is Set, Thr or Ala, n is 1 or 0, its functional derivative, and a pharmaceutically acceptable salt thereof.
Further, the invention provides an antidementia agent containing, as a pharmaceutically active component, an effective amount of the peptide having the above formula (II), its functional derivative or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier or diluent.
The invention further provides a novel peptide having the formula (III):
A-Ser-Pip-Arg (III)
wherein A is Pro-Asn-, Ash- or Pro-, its functional derivative, and a pharmaceutically acceptable salt thereof.
Further, the invention provides an antidementia agent containing, as a pharmaceutically active component, an effective amount of the peptide having the above formula (III), its functional derivative or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier or diluent.
The invention provides a novel peptide having the formula (IV): ##STR7## wherein A is cyclopentylcarbonyl, Pro or pGlu; B is Gly or β-Ala; W represents a hydrogen atom or a Group having the formula (V): ##STR8## or a peptide having the formula (VI): ##STR9## wherein A and B have the same meanings as mentioned above, respectively, its functional derivative, and a pharmaceutically acceptable salt thereof.
Further, the invention provides an antidementia agent containing, as a pharmaceutically active component, an effective amount of the peptide having the above formula (IV), its functional derivative or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier or diluent.
The invention further provides a novel peptide having the formula (VII):
pGlu-Asn-Ser-A-B-(Gly).sub.n (VII)
wherein A is Aze, D- or L-Pro, Pip or Sat, B represents D-or L-Arg, Cit, Har, Lys or Orn, n is 1 or 0, its functional derivative, and a pharmaceutically acceptable salt thereof.
Further, the invention provides an antidementia agent containing, as a pharmaceutically active component, an effective amount of the peptide having the above formula (VII), its functional derivative or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier or diluent.
The invention further provides a novel peptide having the formula (VIII):
Pro-(Asn).sub.m -Ser-L-(D-)Pro-Arg-(Gly).sub.n (VIII)
wherein m and n are independently 0 or 1, its functional derivative, and a pharmaceutically acceptable salt thereof.
Further, the invention provides an antidementia agent containing, as a pharmaceutically active component, an effective amount of the peptide having the above formula (VIII), its functional derivative or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier or diluent.
The above-mentioned peptides, their functional derivatives, and their pharmaceutically acceptable salts show prominent a nootropic effect in passive avoidance tests using rats, and are prominently effective as active component of pharmaceutical agent for prevention or treatment of senile dementia (Alzheimer's dementia), cerebrovascular dementia and other dementia diseases.
DETAILED DESCRIPTION OF THE INVENTION
The peptides and peptide derivatives having the above formulae of the present invention are compounds of which amino acid sequences are different from those of the aforementioned known peptides.
The word of "functional derivatives" of the peptides and peptide derivatives in the present specification means the following derivatives:
a) N-acyl derivatives having N-acyl group(s); wherein N-acyl group is derived from an aliphatic carboxylic acid having 1 to 6 carbon atoms, preferably one derived from acetic acid; the N-acyl group can be expressed by --NHCOR (wherein R is an alkyl group having 1-5 carbon atoms),
b) derivatives having groups in the form of amides, or monoalkyl or dialkyl substituted-amides having alkyl chain(s) of 1 to 6 carbon atoms; which can be expressed by --CONH 2 , --CONHR, and --CONR 2 (wherein R is an alkyl group having 1-6 carbon atoms),
and
c) derivatives having groups in the form of esters derived from alcohol having 1 to 18 carbon atoms, preferably those derived from an aliphatic alcohol having 1 to 6 carbon atoms; which can be expressed by --COOR (wherein R is an alkyl group having carbon 1-18 atoms, preferably 1-6 carbons).
As the examples of pharmaceutically acceptable salts of the peptides and the peptide derivatives of the invention, acid addition salts and basic salts such as alkali metal salts and ammonium salts can be mentioned. Examples of such acid addition salts include salts of inorganic acids (e.g., hydrochloric acid, sulfuric acid and phosphoric acid) or of organic acids (e.g., acetic acid, propionic acid, citric acid, tartaric acid, maleic acid, oxalic acid and methanesulfonic acid). Examples of basic salts include sodium salt, potassium salt, and triethylamine salts. In the specification, amino acids, peptides, protecting groups and solvents are described by abbreviations commonly used in the field of chemistry, or abbreviations recommended by the IUPAC-IUB Commission on Biochemical Nomenclature. For example, the following symbols are used in the specification. The amino acids should be construed to be of the L-type, unless specific description with respect to optical configuration is given.
β-Ala : β-alanine
Arg : arginine
Ala : alanine
Asn : asparagine
Aze : azetidine-2-carboxylic acid
Cit : citrulline
Cys : cysteine
Gly : glycine
Har : homoarginine
Lys : lysine
Orn : ornithine
pGlu : pyroglutamic acid
Pip : pipecolic acid
Pro : proline
Sar : sarcosine
Ser : serine
Thr : threonine
Boc : t-butoxycarbonyl
Z : benzyloxycarbonyl
Fmoc : 9-fluorenylmethoxycabonyl
Bu t : t-butyl
Mbs : p-methoxybenzenesulfonyl
MBzl : p-methoxybenzyl
Acm : acetamidomethyl
Scm : S-carbomethoxysulfenyl
Mtr : 4-methoxy-2,3,6-trimethylbenzenesulfonyl
NO 2 : nitro
Bzl : benzyl
OBzl : benzyl ester
OSu : N-hydroxysuccinimide ester
DCC : N,N'-dicyclohexylcarbodiimide
DCUrea : N,N'-dicyclohexylurea
DIC : N,N'-diisopropylcarbodiimide
HOBt : 1-hydroxybenzotriazole
Et 3 N : triethylamine
Trt : trityl
NMM : N-methylmorpholine
TFA : trifluoroacetic acid
MSA : methanesulfonic acid
AcOEt : ethyl acetate
AcOH : acetic acid
THF : tetrahydrofuran
DMF : N,N-dimethylformamide
MeOH : methanol
The compounds of the present invention can be prepared by the methods conventionally employed in peptide chemistry. For example, the peptides can be prepared by those processes described in Schroder and Lubke, The Peptides, Vol. 1, Academic Press, New York, 1965, and Nobuo Izuraiya et al., Fundamental and Experiment of Peptide Synthesis, Maruzen, Tokyo, 1985, and can be prepared by either the solution synthesis or the solid synthesis.
Examples of the methods for formation of the peptide bonds include azide method, acid chloride method, symmetrical anhydride method, mixed anhydride method, carbodiimide method, carbodiimido-additive method, activated ester method, carbonyldiimidazole method, oxidation-reduction method, and the one employing a Woodward reagent K.
In the synthesis of peptide, the cystine moiety which is an amino acid forming the peptide of the invention can be formed by employing a cystine derivative or by converting a cysteine moiety of the peptide chain into a cystine moiety after the formation of the peptide chain by the conventional method.
Before carrying out the coupling reaction, carboxyl group, amino group, guanidino group, hydroxyl group, mercapto group and the like which do not participate in the reaction can be protected, and those which participate in the coupling reaction can be activated, both by the methods well known in the art.
Examples of the protecting groups for the carboxyl group include ester-forming groups such as methyl, ethyl, benzyl, p-nitrobenzyl, t-butyl and cyclohexyl.
Examples of the protecting groups for the amino group include benzyloxycarbonyl, t-butoxycarbonyl, isobornyloxycarbonyl, and 9-fluorenylmethyloxycarbonyl.
Examples of the protecting groups for the guanidino group include nitro, benzyloxycarbonyl, tosyl, p-methoxybenzenesulfonyl and 4-methoxy-2,3,6-trimethylbenzenesulfonyl.
Examples of the protecting groups for the hydroxyl group include t-butyl, benzyl, tetrahydropyranyl and acetyl.
Examples of the protecting groups for the mercapto group include trityl, acetamidomethyl, benzyl, p-methoxybenzyl and 3-nitro-2-pyridinesulfenyl.
Examples of the activated forms of carboxyl group include symmetrical anhydride, azide and active ester (ester with alcohol e.g., pentachlorophenol, 2,4-dinitrophenol, cyanomethyl alcohol, p-nitrophenol, N-hydroxy-5-norbornene-2,3-dicarboxyimide, N-hydroxysuccinimide, N-hydroxyphthalimide and 1-hydroxybenzotriazol). An example of the activated amino group is amide phosphate.
The reaction is generally carried out in a solvent such as chloroform, dichloromethane, ethyl acetate, N,N-dimethylformamide, dimethylsulfoxide, pyridine, dioxane, tetrahydrofuran, water, methanol and mixture of these solvents.
The reaction temperature may be in the range of approx. -30° C. to 50° C., which is generally employed for the reaction.
The reactions for removing the protecting group of the peptide of the invention may differ depending on the kind of the protecting group, but it should be the one which is able to release the protecting group without giving any influence to the peptide bonding.
The protecting group can be removed by acid treatment, for example, treatment with hydrogen chloride, hydrogen bromide, hydrogen fluoride, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid and mixture of these acids. Further, the reduction with sodium metal in liquid ammonia or catalytic reduction over palladium-carbon can be employed. In performing the reaction for removing the protecting group by the above acid treatment, addition of cation scavenger such as anisole, phenol and thioanisole is advantageously adopted.
After the reaction is complete, the prepared peptide of the present invention can be recovered by the conventional process for purification of peptides, for example, extraction, partition, reprecipitation, recrystallization or column chromatography.
Further, the peptides of the present invention can be converted into their functional derivatives or their pharmaceutically acceptable salts as described above in the conventional manner.
The compounds of the invention show a strong hoottopic effect in passive avoidance tests using rats as described hereinafter.
The peptides and peptide derivatives of the present invention are effective to the following diseases, and be employed for prevention or treatment thereof: senile dementia (Alzheimer's dementia), cerebrovascular dementia, and demntia based on Alzheimer's disease, Pick's disease, Huntington's disease, Creutzfeldt-Jakob disease, Parkinson's disease and cerebellar myelic denatured disease.
The peptides of the invention have an extremely low toxicity, and cause no death even by administration at an extremely higher dose than its effective dose.
The peptides of the invention may be administrated in the form of the peptides of the above-mentioned formulae, their functional derivatives or salt thereof. No matter their forms are, the dose as amount of the peptides of the above-mentioned formulae, is preferably in the range of 0.1 ng/day to 1 mg/day. In the case of parenteral administration and nasal administration, the dose preferably is in the range of 0.1 ng/day to 100 μg/day. In the case of oral administration and rectal administration, it is preferable that the dose should be 10 to 100 times to that of the parenteral administration. The peptide of the invention is mainly administered parenterally (e.g., intravenous or hypodermic injection, intracerebroventricular or intraspinal administration, nasal administration and rectal administration). It can be also administered orally depending on the case.
The peptides of the invention can be incorporated into pharmaceutical compositions in the form of injection liquid, suppository, powder, collunarium, granule and tablets. The peptides of the invention can be preserved as a physiological saline solution or can be freeze-dried in an ample after addition of mannitol or sorbitol and is melted when it is used for administration.
Examples of the invention are set forth hereinafter.
In each example, the eluents used for a thin-layer chromatography were as follows. As for the solid phase, TLC Plate Silica Gel 60F 254 by Merck Co., Ltd. was used.
Rf 1: choroform-methanol - acetic acid -water
(80:20:2.5:5) lower layer
Rf 2: choroform-methanol-water
(70:30:5)
Rf 3: n-butanol -acetic acid-water
(2:1:1)
Further, purification by a high-performance liquid chromatography was carried out using the following materials:
Column: μBondapak C 18 1.9×15
Mobile phase: A) 0.05 % TFA, B) acetonitrile
The preparation of peptide in solid phase was carried out by the process in which the peptide chain was extended step by step in the following manner using 1 g (0.24 mmol NH 2 /g) of 2,4 -dimethoxybenzhydrylamine resin [J. Org. Chem., 52 (1987), 1197].
______________________________________ periodreagent, solvent (minute) × times______________________________________Coupling Process1. DMF 1 × 32. Fmoc-amino acid + HOBt + DIC 120(each of them are same amount.)-DMF3. DMF 1 × 34. iso-propanol 1 × 35. CH.sub.2 Cl.sub.2 1 × 3N.sup.α -Deprotection Process6. DMF 1 × 37. 20% piperidine-DMF 18. 20% piperidine-DMF 209. DMF 1 × 310. CH.sub.2 Cl.sub.2 1 × 3______________________________________
The coupling reaction was confirmed by Kayser test. If necessary, the above steps 1-5 were repeated.
EXAMPLE 1 ##STR10##
Fmoc-Gly-OH-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin, 214 mg of Fmoc-Gly-OH, 110 mg of HOBt and 0.12 ml of DIC by the steps 1-5 in the coupling process.
Then the protecting group was removed by the steps 6-10 in the N.sup.α -deprotection process to obtain H-Gly-resin.
The coupling and N.sup.α -deprotection processes were repeated in the same manner to prepare H-Asn-Cys(Trt)-Sar-Arg(Mtr)-Gly-resin, followed by another coupling process using pGlu-OH to obtain pGlu-Asn-Cys(Trt)-Sar-Arg(Mtr)-Gly-resin. After drying, the resin was stirred in TFA-anisole-thiophenol (10-1-1 ml) for 4 hours, filtered and washed with TFA.
After the TFA solution was placed for 2 hours at room temperature, TFA was distilled off. To the residue, a mixture of ether and water was added. Aqueous portion was collected and freeze-dried.
The obtained freeze-dried peptide was dissolved in 10 ml of 0.05 % aqueous TFA solution. 40 rag of cystine S-monoxide was added to the solution under chilling with ice, and the resulting mixture was stirred for 30 minutes.
Then the resulting solution was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10 % (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 98 rag
R f 3 : 0.10
[α] D : -137.8° (c=0.5, water )
FAB mass spectrum (M+1) : 749
EXAMPLE 2 ##STR11##
pGlu-Asn-Cys(Trt)-Pro-Har(Mtr)-Gly-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin in the same manner as in Example 1. After TFA treatment, the resulting resin was reacted with cystine S-monoxide in the same manner as in Example 1.
Then the purification was carried out by high-performance liquid chromatography, and ion exchange treatment was performed in the same manner as in Example 1, followed by freeze-drying to obtain the desired compound.
Yield: 108 mg
R f 3 : 0.10
[α] D : -161.6° (c=0.5, water)
FAB mass spectrum (M+1) : 789
EXAMPLE 3 ##STR12##
pGlu-Asn-Cys(Trt)-Pro-Cit-Gly-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin in the same manner as in Example 1. After TFA treatment, the resulting resin was reacted with cystine S-monoxide in the same manner as in Example 1.
Then the purification was carried out by high-performance liquid chromatography, and ion exchange treatment was performed in the same manner as in Example 1, followed by freeze-drying to obtain the desired compound.
Yield: 92 mg
R f 3 : 0.12
[α] D : -165.6° (c=0.5, water)
FAB mass spectrum (M+1) : 776
EXAMPLE 4 ##STR13##
pGlu-Asn-Cys(Trt)-Arg(Mtr)-Arg(Mtr)-Gly-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin in the same manner as in Example 1. After TFA treatment, the resulting resin was reacted with cystine S-monoxide in the same manner as in Example.
Then the purification was carried out by high-performance liquid chromatography, and ion exchange treatment was performed in the same manner as in Example 1, followed by freeze-drying to obtain the desired compound.
Yield: 99 mg
R f 3 : 0.06
[α] D : -108.8° (c=0.5, water)
FAB mass spectrum (M+1) : 834
EXAMPLE 5 ##STR14##
pGlu-Asn-Cys(Trt)-Pip-Arg(Mtr)-Gly-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin in the same manner as in Example 1. After TFA treatment, the resulting resin was reacted with cystine S-monoxide in the same manner as in Example 1.
Then the purification was carried out by high-performance liquid chromatography, and ion exchange treatment was performed in the same manner as in Example 1, followed by freeze-drying to obtain the desired compound.
Yield: 55 mg
R f 3 : 0.09
[α] D : -134.4° (c=0.5, water)
FAB mass spectrum (M+1) : 7 89
EXAMPLE 6 ##STR15##
pGlu-Asn-Cys(Trt)-Aze-ArG(Mtr)-Gly-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin in the same manner as in Example 1. After TFA treatment, the resulting resin was reacted with cystine S-monoxide in the same manner as in Example 1.
Then the purification was carried out by high-performance liquid chromatography, and ion exchange treatment was performed in the same manner as in Example 1, followed by freeze-drying to obtain the desired compound.
Yield: 98 mg
R f 3 : 0.08
[α] D : -159.0° (c=0.5, water)
FAB mass spectrum (M+1) : 761
EXAMPLE 7
H-Asn-Ser-Pro-Arg-OH acetate
(1) Boc-Pro-ArG(NO 2 )-OBzl
To a solution of 15 g of H-Arg(NO 2 )-OBzl in 250 ml of THF, 15 G of Boc-Pro-OSu was added under chilling with ice, followed by stirring for 18 hours at room temperature.
After THF was distilled off, the residue was dissolved in AcOEt. The AcOEt solution was washed successively with dilute HCl saturated aqueous NaHCO 3 solution and water, followed by drying over anhydrous Na 2 SO 4 .
AcOEt was distilled off. The residue was dissolved in CHCl 3 -MeOH, and purified by silica-gel column chromatography to obtain the desired compound as an oily product.
Yield: 22 g
R f 1 0.61, R f 2 : 0.77
[α] D : 37.1° (c=1.0, DMF)
(2) Boc-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl
22 g of Boc-Pro-Arg(NO 2 )-OBzl was placed in 110 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the solvent was distilled off.
After drying under reduced pressure, the residue was dissolved in 150 ml of DMF. To the solution, 9 ml of Et 3 N, 12.8 g of Boc-Ser(Bzl)-OH, 10 g of HOBt and 9.4 g of DCC were added under chilling with ice, followed by stirring for 18 hours at room temperature.
DCUrea was removed by filtration, and DMF was distilled off. The residue was dissolved in AcOEt. Then the AcOEt solution was washed successively with dilute HCl, saturated aqueous NaHCO 3 solution and water, followed by drying over anhydrous Na 2 SO 4 .
AcOEt was distilled off, and the residue was treated with AcOEt-ether to give the desired compound as a crystalline product.
Yield: 21 Q
M.P. 80°-82° C.
R f 1 : 0.67, R f 2 : 0.83
[α] D -30.8° (c=1.0, DMF)
(3) Z-Asn-Ser (Bzl) - Pro-Arg (NO 2 ) -OBzl
4.0 9 of Boc-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl was placed in 15 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and the solvent was distilled off.
To the residue, 2-butanol - CH 2 Cl 2 (5:1 v/v) and saturated aqueous NaHCO3 solution was added. The organic portion was collected and washed with saturated aqueous NaCl solution, followed by drying over anhydrous Na 2 SO 4 .
The solvent was distilled off, and the residue was dissolved in 50 ml of DMF. To the solution, 1.55 g of Z-Asn-OH, 1.3 g of HOBt and 1.3 g of DCC were added under chilling with ice.
After stirring for 18 hours at room temperature, DCUrea was removed by filtration, and DMF was distilled off.
The residue was dissolved in 2-butanol - CH 2 Cl 2 (5:1 v/v). Then the solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl saturated with NaCl and saturated aqueous NaCl solution, followed by drying over anhydrous Na 2 SO 4 .
The solvent was distilled off, and the residue was treated with ether to give the desired compound as a crystalline product.
Yield: 4.5 g
M.P. : 205°-209° C. (decomposed)
R f 1 : 0.55, R f 2 : 0.72
[α] D : -25.1° (c=1.0, DMF) (4) H-Asn-Ser-Pro-Arg-OH acetate
A solution of 150 mg of Z-Asn-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl in 20 ml of 80 % acetic acid was stirred for 18 hours in a stream of hydrogen gas in the presence of 10 % palladium-carbon.
The palladium-carbon was removed by filtration, and the solvent was distilled off. The residue was dissolved in water, then freeze-dried.
Then the resulting product was purified by high-performance liquid chromatography at 12 ml/min.(flow rate), 0 to 10 % (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 82 mg
R f 3 : 0.15
[α] D : -70.4° (c=0.5, water)
FAB mass spectrum (M+1) : 473
EXAMPLE 8
H-Asn-Thr-Pro-Arg-OH acetate
(1) Boc-Thr-Pro-Arg (NO 2 )-OBzl
9.6 g of Boc-Pro-Arg(NO 2 )-OBzl was placed in 50 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and the solvent was distilled off.
After drying under reduced pressure, the residue was dissolved in 100 ml of DMF. To the solution, 4 ml of Et 3 N and 6 g of Boc-Thr-OSu were added under chilling with ice, followed by stirring for 18 hours at room temperature.
DMF was distilled off and the residue was dissolved in AcOEt. Then the AcOEt solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl and water, followed by drying over anhydrous Na 2 SO 4 .
AcOEt was distilled off, and the residue was purified with CHCl 3 -acetone by silica-gel column chromatography, then was treated with ether to give the desired compound as a crystalline product.
Yield: 7.1 g
M.P. : 86°-91° C.
R f 1 : 0.59, R f 2 : 0.77
[α] D : -37.5° (c=1.0, DMF)
(2) Z-Asn-Thr-Pro-Arg (NO 2 ) -OBzl
The desired compound was prepared from 3.0 g of Boc-Thr-Pro-Arg(NO 2 )-OBzl, 15 ml of 4 N HCl-AcOEt, 1.2 g Z-Ash-OH, 1.2 g of HOBt and 1.1 g of DCC in the same manner as in Example 7-(3).
Yield: 2.4 l
M.P. 184°-186° C.
R f 1 : 0.39, R f 2 : 0.62
[α] D : -30.2° (c=1.0, DMF)
(3) H-Asn-Thr-Pro-Arg-OH acetate
150 mg of Z-Asn-Thr-Pro-Arg(NO 2 )-OBzl was reduced in the presence of palladium-carbon in the same manner as in Example 7-(4). The resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), to 10 % (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 104 mg
R f 3 : 0.17
[α] D : -58.5° (c=0.5, water)
FAB mass spectrum (M+1) : 487
EXAMPLE 9
H-Asn-Ala-Pro-Arg-OH acetate
(1) Boc-Ala-Pro-Arg (NO 2 )-OBzl
The desired compound was prepared from 28.9 g of Boc-Pro-Arg (NO 2 )-OBzl, 150 ml of 4 N HCl-AcOEt, 8 ml of Et 3 N and 16.3 g of Boc-Ala-OSu in the same manner as in Example 8-(1) .
Yield: 25.0 g
M.P. : 83°-85° C.
R f 1 : 0.61, R f 2 : 0.77 [α] D : -54.2° (c=1.0, DMF)
(2) Z-Asn-Ala-Pro-Arg(NO 2 )-OBzl
The desired compound was prepared from 2.9 g of Boc-Ala-Pro-Arg(NO 2 )-OBzl, 15 ml of 4 N HCl-AcOEt, 1.4 g of Z-Asn-OH, 1.0 g of HOBt and 1.1 g of DCC in the same manner as in Example 7- (3 ) .
Yield: 2.8 g
M.P. 128°-130° C.
R f 1 : 0.45, R f 2 : 0.65
[α] D : -36.8° (c=1.0, DMF)
(3) H-Asn-Ala-Pro-Arg-OH acetate
150 mg of Z-Asn-Ala-Pro-Arg(NO 2 )-OBzl was reduced in the presence of palladium-carbon in the same manner as in Example 7-(4). The resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 rain, linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 100 mg
R f 3 : 0.14
[α] D : -78.5° (c=0.5, water)
FAB mass spectrum (M+1) : 457
EXAMPLE 10
H-Asn-Ser-D-Pro-Arg-OH acetate
(1) Boc-D-Pro-Arg (NO 2 )-OBzl
The desired compound was prepared as an oily product from 9 g of H-Arg(NO 2 )-OBzl and 9 g of Boc-D-Pro-OSu in the same manner as in Example 7-(1).
Yield: 13 g
R f 1 : 0.64, R f 2 : 0.76
[α] D +9.6° (c=1.9, DMF)
(2) Boc-Ser(Bzl)-D-Pro-Arg(NO 2 )-OBzl
The desired compound was prepared as an oily product from 12 g of Boc-D-Pro-Arg(NO 2 )-OBzl, 60 ml of 4 N HCl-AcOEt, 3.3 ml of Et 3 N, 7 g of Boc-Ser(Bzl)-OH, 4.2 g of HOBt and 5.1 g of DCC in the same manner as in Example 7-(2).
Yield: 10 g
R f 1 : 0.71, R f 2 : 0.80
[α] D : +7.4° (c=1.0, DMF)
(3) Z-Asn-Ser(Bzl)-D-Pro-Arg (NO 2 )-OBzl
The desired compound was prepared from 3.0 g of Boc-Ser(Bzl)-D-Pro-Arg(NO 2 )-OBzl, 10 ml of 4 N HCl-AcOEt, 1.2 g of Z-Ash-OH, 0.9 g of HOBt and 0.95 g of DCC in the same manner as in Example 7-(3) .
Yield: 2.5 g
M.P. 89°-92° C.
R f 1 : 0.59, R f 2 : 0.72 [α] D +14.8° (c=1.0, DMF)
(4) H-Asn-Ser-D-Pro-Arg-OH acetate
100 mg of Z-Asn-Ser(Bzl)-D-Pro-Arg(NO 2 )-OBzl was reduced in the presence of palladium-carbon in the same manner as in Example 7-(4). The resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 48 mg
R f 3 : 0.13
[α] D : +25.3° (c=0.5, water)
FAB mass spectrum (M+1) : 473
EXAMPLE 11
H-Asn-Ser-Pro-Arg-Gly-NH 2 acetate
Fmoc-Gly-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin, 214 mg of Fmoc-Gly-OH, 110 mg of HOBt and 0.12 ml of DIC by the above described coupling process.
Then the protecting group was removed by N.sup.α -deprotection process to obtain H-Gly-resin.
The coupling and N.sup.α -deprotection processes were repeated in the same manner to prepare H-Asn-Ser (Bu t )-Pro-Arg(Mtr)-Gly-resin. After drying, the resin was stirred in TFA-anisole (10-1 ml) for 4 hours at room temperature. The resin was removed by filtration and was washed with TFA.
After the TFA solution was placed for 2 hours at room temperature, TFA was distilled off. To the residue, ether-water was added, and the aqueous portion was collected and was subjected to Dowex 1×2 (acetate type) treatment and freeze-dried.
Then the resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 56 mg
R f 3 : 0.11
[α] D : -78.8° (c=0.5, water)
FAB mass spectrum (M+1) : 529
EXAMPLE 12
H-Asn-Ser-Pip-Arg-OH acetate
(1) Boc-Pip-Arg(NO 2 )-OBzl
To a solution of 10.6 g of H-Arg(NO 2 )-OBzl in 100 ml of DMF, 7.1 g of Boc-Pip-OH, 7.1 g of HOBt and 6.7 g of DCC were added under chilling with ice. The mixture was stirred for 18 hours at room temperature. The produced DCUrea was removed by filtration, and DMF was distilled off.
The residue was dissolved in AcOEt. The resulting solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl and water, followed by drying over anhydrous Na 2 SO 4 .
AcOEt was distilled off, and the residue was purified with CHCl 3 -acetone by silica-gel column chromatography to obtain the desired compound as an oily product.
Yield: 5.5 g
R f 1 : 0.68, R f 2 : 0.80
[α] D :-24.0° (c=1.0, DMF)
(2) Boc-Ser(Bzl)-Pip-Arg(NO 2 )-OBzl
5.2 g of Boc-Pip-Arg(NO 2 )-OBzl was placed in 25 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the solvent was distilled off.
The residue was dried under reduced pressure and then dissolved in 50 ml of DMF. To the resulting solution, 1.4 ml of Et 3 N and 3.9 g of Boc-Ser(Bzl)-OSu were added under chilling with ice, and then stirred for 18 hours at room temperature.
DMF was distilled off and the residue was dissolved in AcOEt. The resulting solution was washed successively with H saturated aqueous NaHCO 3 solution, dilute HCl and water, followed by drying over anhydrous Na 2 SO 4 .
AcOEt was distilled off, and the residue was purified with CHCl 3 -acetone by silica-gel column chromatography to obtain the desired compound as an oily product.
Yield: 2.8 g
R f 1 : 0.74, R f 2 : 0.86
[α] D : -42.6° (c=1.0, DMF)
(3) Boc-Asn-Ser(Bzl)-Pip-Arg(NO 2 )-OBzl
1.6 g of Boc-Ser(Bzl)-Pip-Arg(NO 2 )-OBzl was placed in 6 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the solvent was distilled off.
To the residue, 2-butanol CH 2 Cl 2 (5:1 v/v) and saturated aqueous NaHCO 3 solution were added. The organic portion was collected and then the solution was washed with saturated aqueous NaCl solution, followed by drying over anhydrous Na 2 SO 4 .
The solvent was distilled off, and then the residue was dissolved in 20 ml of DMF. To the resulting solution, 0.53 g of Boc-Asn-OH, 0.53 g of HOBt and 0.52 g of DCC were added under chilling with ice.
The resulting solution was stirred for 18 hours at room temperature, and then DCUrea was removed by filtration and DMF was distilled off.
The residue was dissolved in AcOEt, and the solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl and saturated aqueous NaCl solution, followed by drying over anhydrous Na 2 SO 4 .
The solvent was distilled off, and the residue was purified with CHCl 3 -MeOH by silica-gel column chromatography to obtain the desired compound as an oily product.
Yield: 1.0 g
R f 1 : 0.57, R f 2 : 0.74
[α] D : -37.8° (c=1.0, DMF)
(4) H-Asn-Ser-Pip-Arg-OH acetate
150 mg of Boc-Asn-Ser(Bzl)-Pip-Arg(NO 2 )-OBzl was placed in 0.5 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the solvent was distilled off.
To the residue, 20 ml of 80% acetic acid was added and then the resulting mixture was stirred for 18 hours in a stream of hydrogen gas in the presence of 10% palladium-carbon.
The palladium-carbon was removed by filtration, and the solvent was distilled off. The residue was dissolved in water, and then freeze-dried.
Then the resulting product was purified by high-performance liquid chromatography at 12 ml/min.(flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 63 mg
R f 3 : 0.19
[α] D : -46.2° (c=0.5, water)
FAB mass spectrum (M+1) : 487
EXAMPLE 13
H-Pro-Ser-Pip-Arg-OH acetate
(1) Z-Pro-Set (Bzl) -Pip-Arg (NO 2 )-OBzl
The desired compound was prepared as an oily product from 1.0 g of Boc-Ser(Bzl)-Pip-ArG(NO 2 )-OBzl, 5 ml of 4 N HCl-AcOEt, 0.2 ml of Et 3 N and 0.49 g of Z-Pro-OSu in the same manner as in Example 12- (1 ).
Yield: 0.9 g
R f 1 : 0.72, R f 2 : 0.82
[α] D : -51.2° (c=1.0, DMF)
(2) H-Pro-Ser-Pip-Arg-OH acetate
150 mg of Z-Pro-Ser(Bzl)-Pip-ArG(NO 2 )-OBzl was reduced in the presence of palladium-carbon in the same manner as in Example 12-(4). The resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 31 mg
R f 3 : 0.18
[α] D :-76.5° (c=0.5, water)
FAB mass spectrum (M+1) : 470
EXAMPLE 14
H-Pro-Asn-Set-Pip-Arg-OH acetate
(1) Z-Pro-Asn-Ser(Bzl)-Pip-Arg(NO 2 )-OBzl
The desired compound was prepared from 0.68 g of Boc-Asn-Ser(Bzl)-Pip-ArG(NO 2 )-OBzl, 3 ml of 4 N HCl-AcOEt, 0.14 ml of NMM and 0.32 g of Z-Pro-OSu in the same manner as in Example 12-(2) .
Yield: 0.7 g
M.P. 95°-97° C.
R f 1 : 0.57, R f 2 : 0.74
[α] D -48.2° (c=1.0, DMF)
(2) H-Pro-Asn-Ser-Pip-Arg-OH acetate
150 mg of Z-Pro-Asn-Ser(Bzl)-Pip-Arg(NO 2 )-OBzl was reduced in the presence of palladium-carbon in the same manner as in Example 12-(4). The resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 60 mg
R f 3 : 0.14
[α] D : -76.4° (c=0.5, water )
FAB mass spectrum (M+1) : 584
EXAMPLE 15 ##STR16##
(1) Z-Arg(Mbs)-Gly-NH 2
In a mixture of 100 ml of AcOEt and 70 ml of 5% aqueous citric acid was dissolved under stirring 10 g of Z-Arg(Mbs)-OH dicyclohexylamine salt. The AcOEt portion was washed with water and dried over anhydrous Na 2 SO 4 .
The solvent was distilled off. The residue was dissolved in 100 ml of DMF. To the DMF solution were added under chilling with ice 1.7 g of H-Gly-NH 2 hydrochloride, 1.7 ml of NMM, 2 g of HOBt and 3.4 g of DCC. The mixture was stirred for 18 hours at room temperature. The produced DCUrea was removed by filtration, and DMF was distilled off.
The residue was dissolved in a mixture of 2-butanol and CH 2 Cl 2 (5:1, v/v). The resulting solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl saturated with NaCl and saturated aqueous NaCl solution, and then dried over anhydrous Na 2 SO 4 .
The solvent was distilled off. The residue was treated with MeOH-ether to give the desired compound as a crystalline product.
Yield: 5.0 g
M.P. : 201°-202° C.
R f 1 0.26 Rf 2 0.55
[α] D +2.1° (c=0.5, DMF)
(2) BoC-Pro-ArG(Mbs)-Gly-NH 2
A solution of 20.8 g of Z-Arg(Mbs)-Gly-NH 2 in 200 ml of 80% AcOH was stirred for 6 hours in a stream of hydrogen in the presence of 10% palladium-carbon.
The palladium-carbon was then removed by filtration and the solvent was distilled off from the filtrate. The residue was dried under reduced pressure and then dissolved in 200 ml of DMF. To the resulting solution were added 4.3 ml of NMM and 12.1 g of Boc-Pro-OSu, and the mixture was stirred for 18 hours at room temperature.
DMF was distilled off. The residue was dissolved in a mixture of 2-butanol and CH 2 Cl 2 (5:1, v/v). The resulting solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl saturated with NaCl and saturated aqueous NaCl solution, and then dried over anhydrous Na 2 SO 4 .
The solvent was distilled off. The residue was treated with ether to give the desired compound as a crystalline product.
Yield: 21.5 g
M.P. : 120°-126° C.
R f 1 : 0.31 R f 2 : 0.53
[α] D -26.5° (c=1, DMF)
(3) Boc-Cys(Acm)-Pro-Arg(Mbs)-Gly-NH 2
9.8 g of Boc-Pro-Arg(Mbs)-Gly-NH 2 was placed in a mixture of 100 ml of THF and 100 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the solvent was distilled off.
The residue was dried under reduced pressure and then dissolved in 100 ml of DMF. To the DMF solution were added under chilling with ice 3.6 ml of NMM, 5.2 g of Boc-Cys(Acm)-OH, 2.7 g of HOBt and 3.7 g of DCC. The mixture was stirred for 18 hours at room temperature.
The DCUrea was removed by filtration, and DMF was distilled off. The residue was dissolved in a mixture of 2-butanol and CH 2 Cl 2 (5:1, v/v). The resulting solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl saturated with NaCl and saturated aqueous NaCl solution, and then dried over anhydrous Na 2 SO 4 .
The solvent was distilled off. The residue was treated with ether to give the desired compound as a crystalline product.
Yield: 10.0 g
M.P. 110°-116° C.
R f 1 : 0.24, R f 2 : 0.50
[α] D : 58.2° (c=0.5, DMF)
(4) Z-pGlu-Cys(Acm)-Pro-Arg(Mbs)-Gly-NH 2
1.6 g of Boc-Cys(Acm)-Pro-Arg(Mbs)-Gly-NH 2 was placed in 10 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the solvent was distilled off.
The residue was dried under reduced pressure and then dissolved in 20 ml of DMF. To the mixture were added under chilling with ice 0.22 ml of NMM and 0.86 g of Z-pGlu-OSu. The mixture was stirred for 18 hours at room temperature.
DMF was distilled off. The residue was dissolved in a mixture of 2-butanol and CH 2 Cl 2 (5:1, v/v). The resulting solution was washed successively with saturated NaHCO 3 aqueous solution, dilute HCl saturated with NaCl and saturated NaCl aqueous solution, and then dried over anhydrous Na 2 SO 4 .
The solvent was distilled off. The residue was treated with ether to give the desired compound as a crystalline product.
Yield: 1.4 g
M.P. 95°-99° C.
R f 1 : 0.11, F f 2 : 0.40
[α] D -44.7° (c=1.0, DMF)
(5) Z-pGlu-Cys(Scm)-Pro-Arg(Mbs)-Gly-NH 2
To a solution of 1.3 g of Z-pGlu-Cys (Acm)-Pro-Arg(Mbs)-Gly-NH 2 in 80 ml of CH 2 Cl 2 -MeOH (1:1, v/v) was added under chilling with ice 0.22 ml of Cl-Scm. The resulting mixture was stirred for 20 min.
The solvent was distilled off. The residue was purified with CHCl 3 -MeOH by silica-gel column chromatography to obtain the desired compound as a crystalline product.
Yield: 540 mg
M.P. : 185°-190° C.
R f 1 : 0.19, R f 2 : 0.49
[α] D : -64.0° (c=1.0, DMF) ##STR17##
To a solution of 500 mg of Z-pGlu-Cys(Scm)-Pro-Arg(Mbs)-Gly-NH 2 in 10 ml of DMF was added 210 mg of cysteine hydrochloride and the mixture was stirred for 1 hour at room temperature.
The solvent was distilled off. The residue was purified with CHCl 3 -MeOH by silica-gel column chromatography and was treated with ether to obtain the desired compound as a crystalline product.
Yield: 400 mg
M.P. : 145°-151° C. (decomposed)
R f 2 : 0.12
[α] D : -87.0° (c=1.0, DMF ) ##STR18##
150 mg of Z-pGlu-Cys-Pro-Arg (Mbs)-Gly-NH 2 ##STR19## hydrochloride was placed in a mixture of 2 ml of MSA and 0.2 ml of anisole and the resulting mixture was stirred for 1 hour at room temperature. After addition of ether, the supernatant portion was removed.
The precipitate was dissolved in water. The solution was subjected to Dowex 1×2 (acetate type) treatment and water was distilled off.
The residue was dissolved in 0.05% TFA and purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 40 mg
R f 3 : 0.11
[α] D : 160.4° (c=0.5, water)
FAB mass spectrum (M+1) : 661
EXAMPLE 16 ##STR20##
(1) cyPent-CO-Cys(Acm)-Pro-Arg(Mbs)-Gly-NH 2
1.5 g of Boc-Cys(Acm)-pro-Arg(Mbs)-Gly-NH 2 was placed in 10 ml of 4 N HCl-AcOEt for 30 min. at room temperature and the solvent was distilled off.
The residue was dried under reduced pressure and dissolved in 15 ml of DMF. To the solution were added under chilling with ice 0.32 ml of NMM and anhydrous cyclopentane carboxylic acid (prepared from 0.48 g of cyclopentane carboxylic acid and 0.43 g of DCC) in 2 ml of DMF. The mixture was stirred for 4 hours at room temperature and DMF was distilled off.
The residue was dissolved in 2-butanol-CH 2 Cl 2 (5:1 v/v). The resulting solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl saturated with NaCl and saturated aqueous NaCl solution, and then dried over anhydrous Na 2 SO 4 .
The solvent was distilled off. The residue was purified with CHCl 3 -MeOH by silica-gel column chromatography and was treated with ether to obtain the desired compound as a crystalline product.
Yield: 750 mg
M.P. : 135°-138° C.
R f 1 : 0.16, R f 2 : 0.45
[α] D : -54.7° (C=1.0, DMF)
(2) cyPent-CO-Cys(Scm)-Pro-Arg(Mbs)-Gly-NH 2
The desired compound was prepared from 700 mg of cyPent-CO-Cys(Acm)-Pro-Arg(Mbs)-Gly-NH 2 and 0.14 ml of Cl-Scm in the same manner as in Example 15-(5).
Yield: 640 mg
M.P. : 130°-133° C.
R f 1 : 0.28, R f 2 : 0.55
[α] D : -65.2° (C=1.0, DMF) ##STR21##
The desired compound was prepared from 600 mg of cyPent-CO-CYs(Scm)-Pro-Arg(Mbs)-Gly-NH 2 and 335 mg of cysteine hydrochloride in the same manner as in Example 15-(6).
Yield: 686 mg
M.P. : 142°-145° C.
R f 2 : 0.18
[α] D : -77.8° (c=1.0, DMF) ##STR22## hydrochloride was treated with MSA-anisole in the same manner as in Example 15-(7), purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 5 to 25% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 29 mg
R f 3 : 0.32
[α] D : -167.2° (c=0.5, water)
FAB mass spectrum (M+1) : 646
EXAMPLE 17 ##STR23##
(1) Boc-Pro-Cys(Acm)-pro-Arg(Mbs)-Gly-NH 2
1.5 g of Boc-Cys(Acm)-Pro-Arg(Mbs)-Gly-NH 2 was placed in 10 ml of 4 N HCl-AcOEt for 30 min. at room temperature and the solvent was distilled off.
The residue was dried under reduced pressure and dissolved in 20 ml of DMF. To the solution were added under chilling with ice 0.32 ml of NMM and 0.67 g of Boc-Pro-OSu. After the mixture was stirred for 18 hours at room temperature, and DMF was distilled off.
The residue was dissolved in 2-butanol-CH 2 Cl 2 (5:1 v/v). The resulting solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl saturated with NaCl and saturated aqueous NaCl solution, and then dried over anhydrous Na 2 SO 4 .
The solvent was distilled off. The residue was purified with CHCl 3 -MeOH by silica-gel column chromatography and treated with ether to obtain the desired compound as a crystalline product.
Yield: 0.6 g
M.P. : 165°-168° C.
R f 1 : 0.20, R f 2 : 0.49
[α] D : -83.0° (c=1.0, DMF)
(2 ) Boc-Pro-Cys(Scm)-Pro-Arg(Mbs)-Gly-NH 2
The desired compound was prepared from 450 mg of Boc-Pro-Cys(Acm)-Pro-Arg(Mbs)-Gly-NH 2 and 0.08 ml of Cl-Scm in the same manner as in Example 15-(5) .
Yield: 435 mg
M.P. : 205°-210° C.
R f 1 : 0.33, R f 2 : 0.57
[α] D : -78.4° (c=1.0, DMF) ##STR24##
The desired compound was prepared from 400 mg of Boc-Pro-Cys(Scm)-Pro-Arg(Mbs)-Gly-NH 2 and 197 mg of cysteine hydrochloride in the same manner as in Example 15-(6).
Yield: 416 mg
M.P. : 172°-180° C. (decomposed)
R f 2 : 0.23
[α] D : -82.1° (c=1.0, DMF) ##STR25## hydrochloride was treated with MSA-anisole in the same manner as in Example 15-(7), purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10 (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 22 mg
R f 3 : 0.06
[α] D : -140.6° (c=0.5, water)
FAB mass spectrum (M+1) : 647
EXAMPLE 18 ##STR26##
(1) Boc-Arg(Mbs)-β-Ala-OBzl
To a solution of 3.5 g of H-β-Ala-OBzl p-toluene-sulfonate in 50 ml of DMF were added under chilling with ice 1.4 ml of Et 3 N, 3.0 g of Boc-Arg(Mbs)-OH, 1.3 g of HOBt and 1.5 g of DCC.
The mixture was stirred for 18 hours at room temperature, DCUrea was removed by filtration, and DMF was distilled off.
The residue was dissolved in AcOEt and the resulting solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl and water, and then dried over anhydrous Na 2 SO 4 .
AcOEt was distilled off to give the desired compound as an oily product.
Yield: 3.8 g
R f 1 : 0.55, R f 2 : 0.76
[α] D : -0.5° (c=1.0, DMF)
(2) Boc-Pro-Arg(Mbs)-β-Ala-OBzl
3.6 g of Boc-Arg(Mbs)-β-Ala-OBzl was placed in 15 ml of 4 N HCl-AcOEt for 30 min. at room temperature and the solvent was distilled off.
The residue was dried under reduced pressure and dissolved in 50 ml of DMF. To the solution were added under chilling with ice 1.0 ml of NMM and 2.0 g of Boc-Pro-OSu and the mixture was stirred for 18 hours at room temperature.
DMF was distilled off. The residue was dissolved in AcOEt and washed successively with saturated aqueous NaHCO 3 solution, dilute HCl and saturated aqueous NaCl solution, and then dried over anhydrous Na 2 SO 4 .
AcOEt was distilled off to give the desired compound as an oily product.
Yield: 3.6 g
R f 1 : 0.58, R f 2 : 0.75
[α] D : -28.9° (c=1.0 DMF)
(3) Boc-Cys(Acm)-Pro-Arg(Mbs)-β-Ala-OBzl
The desired compound was prepared from 3.5 g of Boc-Pro-Arg(Mbs)-β-Ala-OBzl, 15 ml of 4 N HCl-AcOEt, 0.82 m NMM and Boc-Cys (Acre)-OH symmetric acid anhydride (prepared from 3.2 g of Boc-Cys (Acre)-OH and 1.1 g of DCC) in the same manner as in Example 16-(1).
Yield: 4.1 g
M.P. : 79°-83° C.
R f 1 : 0.49, R f 2 : 0.74
[α] D : -27.8° (c=1.0, DMF)
(4) Z-PGlu-Cys(Acm)-Pro-Arg(Mbs)-β-Ala-OBzl
The desired compound was prepared as an oily product from 1.7 g of Boc-Cys(Acm)-Pro-Arg(Mbs)-β-Ala-OBzl, 10 ml of 4 N HCl-AcOEt, 0.3 ml of NMM and 0.83 g of Z-pGlu-OSu in the same manner as in Example 15-(4).
Yield: 1.8 g
R f 1 : 0.43, R f 2 : 0.67
[α] D : -42.2° (c=1.0, DMF)
(5) Z-pGlu-CyS(Scm)-Pro-Arg(Mbs)-β-Ala-OBzl
The desired compound was prepared as an oily product from 1.9 g of Z-pGlu-Cys(Acm)-Pro-Arg(Mbs)-β-Ala-OBzl and 0.29 ml of C1-Scm in the same manner as in Example 15-(5).
Yield: 1.2 g
R f 1 : 0.47, R f 2 : 0.73
[α] D : -64.3° (C=1.0, DMF) ##STR27##
The desired compound was prepared from 1.0 g of Z-pGlu-Cys(Scm)-Pro-Arg(Mbs)-β-Ala-OBzl and 0.4 g of cysteine hydrochloride in the same manner as in Example 15-(6).
Yield: 980 mg
M.P. : 133-20 137° C.
R f 2 : 0.45
[α] D : -71.9° (c=1.0, DMF) ##STR28## hydrochloride was treated with MSA-anisole in the same manner as in Example 15-(7), purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 27 mg
R f 3 : 0.14
[α] D : -154.0° (c=0.5, water)
FAB mass spectrum (M+1) : 67 6
EXAMPLE 19
H-Pro-CYs-Pro-Arg-Gly-NH 2 acetate
(1) Z-Pro-Cys(MBzl)-Pro-Arg(Mbs)-Gly-NH 2
The desired compound was prepared from 2.4 g of Boc-Cys(MBzl)-Pro-Arg(Mbs)-Gly-NH 2 10 ml of 4 N HCl-AcOEt, 0.6 ml of NMM and 1.3 g of Z-Pro-OSu in the same manner as in Example 15-(4) .
Yield: 2.3 G
M.P. : 101°-104° C.
R f 1 : 0.41, R f 2 : 0.61
[α] D : -56.4° (c=1.0, DMF)
(2) H-Pro-CYs-Pro-Arg-Gly-NH 2 acetate
150 mg of Z-Pro-Cys(MBzl)-Pro-Arg(Mbs)-Gly-NH 2 was treated with MSA-anisole in the same manner as in Example 15-(7), purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 64 mg
R f 3 (including 0.1% ethanediol) : 0.12
[α] D : -92.7° (c=0.5, water)
FAB mass spectrum (M+1) : 528
EXAMPLE 20 ##STR29##
Into 2 ml of water was dissolved 30 mg of H-Pro-Cys-Pro-ArG-Gly-NH 2 acetate. The resulting solution was adjusted to have pH 7 with dilute aqueous ammonium, stirred for 7 days at room temperature, and then made acidic by addition of acetic acid and freeze-dried.
Yield: 28 mg
R f 3 : 0.02
[α] D : -142.9° (c=0.5, water )
FAB mass spectrum (M+1) : 1054
EXAMPLE 21
pGlu-Asn-Ser-Pro-Arg-Gly-NH 2 acetate
Fmoc-Gly-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin, 214 mg of Fmoc-Gly-OH, 110 mg of HOBt and 0.12 ml of DIC by the above described coupling process.
Then the protecting group was removed by N 60 -deprotection process to obtain H-Gly-resin.
The coupling and N.sup.α -deprotection processes were repeated in the same manner to prepare H-Asn-Ser(Bu t )-Pro-Arg(Mtr)-Gly-resin, and then the coupling process using pGlu-OH were performed to obtain pGlu-Asn-Ser(Bu t )-Pro-Arg(Mtr)-Gly-resin. After drying, the resin was stirred in TFA-anisole (10-1 ml) for 4 hours at room temperature. The resin was removed by filtration and was washed with TFA.
After the TFA solution was placed for 2 hours at room temperature, TFA was distilled off. To the residue, ether-water was added, and the aqueous portion was collected, subjected to Dowex 1×2 (acetate type) treatment and freeze-dried.
Then the resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 69 mg
R f 3 : 0.14
[α] D : -91.8° (c=0.5, water)
FAB mass spectrum (M+1) : 640
EXAMPLE 22
pGlu-Asn-Ser-D-Pro-Arg-Gly-NH 2 acetate
pGlu-Asn-Ser(But)-D-Pro-Arg(Mtr)-Gly-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin in the same manner as in Example 21, and then TFA treatment, purification by high-performance liquid chromatography, ion exchange treatment and freeze-drying were performed in the same manner as in Example 21 to obtain the desired compound.
Yield: 74 mg
R f 3 : 0.15
[α] D : -13.9° (c=0.5, water)
FAB mass spectrum (M+1) : 640
EXAMPLE 23
pGlu-Asn-Ser-Pro-D-Arg-Gly-NH 2 acetate
pGlu-Asn-Ser(But)-Pro-D-Arg(Mtr)-Gly-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin in the same manner as in Example 21, and then TFA treatment, purification by high-performance liquid chromatography, ion exchange treatment and freeze-drying were performed in the same manner as in Example 21 to obtain the desired compound.
Yield: 49 mg
R f 3 : 0.15
[α] D : -67.4° (c=0.5, water)
FAB mass spectrum (M+1) : 640
EXAMPLE 24
pGlu-Asn-Ser-D-Pro-D-Arg-Gly-NH 2 acetate
pGlu-Asn-Ser(Bu t )-D-Pro-D-Arg(Mtr)-Gly-resin was prepared from 1 g of 2,4-dimethoxybenzhydrylamine resin in the same manner as in Example 21, and then TFA treatment, purification by high-performance liquid chromatography, ion exchange treatment and freeze-drying were performed in the same manner as in Example 21 to obtain the desired compound.
Yield: 62 mg
R f 3 : 0.16
[α] D : +15.3° (c=0.5, water)
FAB mass spectrum (M+1) : 640
EXAMPLE 25
pGlu-Asn-Ser-Pro-Arg-OH
(1) Boc-Pro-Arg(NO 2 )-OBzl
To a solution of 15 g of H-Arg(NO 2 )-OBzl in 250 ml of THF, 15 g of Boc-Pro-OSu was added under chilling with ice, followed by stirring for 18 hours at room temperature.
After THF was distilled off, the residue was dissolved in AcOEt. The AcOEt solution was washed successively with dilute HCl saturated aqueous NaHCO 3 solution and water, followed by drying over anhydrous Na 2 SO 4 .
AcOEt was distilled off. The residue was dissolved in CHCl 3 -MeOH, and purified by silica-gel column chromatography to obtain the desired compound as an oily product.
Yield: 22 g
R f 1 : 0.61, R f 2 : 0.77
[α] D : -37.1° (c=1.0, DMF)
(2) Boc-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl
22 g of Boc-Pro-Arg(NO 2 )-OBzl was placed in 110 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the the solvent was distilled off.
After drying under reduced pressure, the residue was dissolved in 150 ml of DMF. To the solution, 9 ml of Et 3 N, 12.8 g of Boc-Ser(Bzl)-OH, 10 g of HOBt and 9.4 g of DCC were added under chilling with ice, followed by stirring for 18 hours at room temperature.
DCUrea was removed by filtration, and DMF was distilled off. The residue was dissolved in AcOEt. Then the AcOEt solution was washed successively with dilute HCl saturated aqueous NaHCO 3 solution, dilute HCl and water, followed by drying over anhydrous Na 2 SO 4 .
AcOEt was distilled off, and the residue was treated with AcOEt to give the desired compound as a crystalline product.
Yield: 21 g
M.P.: 80°-82° C.
R f 1 : 0.67, R f 2 : 0.83
[α] D : -30.8° (c=1.0, DMF)
(3) Z-pGlu-Asn-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl
2.3 g of Boc-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl was placed in 10 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the solvent was distilled off.
To the residue, 2-butanol-CH 2 Cl 2 (5:1 v/v) and saturated aqueous NaHCO 3 solution were added. The organic portion was collected and washed with saturated aqueous NaCl solution, followed by drying over anhydrous Na 2 SO 4 .
The solution was distilled off, and the residue was dissolved in 20 ml of DMF. To the solution, 1.4 g of Z-pGlu-Asn-OH, 0.7 g of HOBt and 0.8 g of DCC were added under chilling with ice.
After stirring for 18 hours at room temperature, DCUrea was removed by filtration, and DMF was distilled off.
The residue was dissolved in 2-butanol CH 2 Cl 2 (5:1 v/v) and then the solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl saturated with NaCl and saturated aqueous NaCl solution, followed by drying over anhydrous Na 2 SO 4 .
The solvent was distilled off, and the residue was dissolved in CHCl 3 -MeOH, and purified by silica-gel column chromatography to obtain the desired compound as a crystalline product.
Yield: 1.9 g
M.P. : 122°-125° C.
R f 1 : 0.46, R f 2 : 0.64
[α] D : -38.6° (c=1.0, DMF)
(4) pGlu-Asn-Ser-Pro-Arg-OH
A solution of 100 mg of Z-pGlu-Asn-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl in 20 ml of 80% acetic acid was stirred for 18 hours in a stream of hydrogen gas in the presence of 10% palladium-carbon.
The palladium-carbon was removed by filtration, and the solvent was distilled off. The residue was dissolved in water, and then freeze-dried.
Then the resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 55 mg
R f 3 : 0.18
[α] D : -85.5° (c=0.5, water)
FAB mass spectrum (M+1) : 584
EXAMPLE 26
H-Pro-Asn-Ser-Pro-Arg-OH acetate
(1) Boc-Pro-Arg(NO 2 )-OBzl
To a solution of 15 g of H-Arg(NO 2 )-OBzl in 250 ml of THF, 15 g of Boc-Pro-OSu was added under chilling with ice, followed by stirring for 18 hours at room temperature.
After THF was distilled off, the residue was dissolved in AcOEt. The AcOEt solution was washed successively with dilute HCl saturated aqueous NaHCO 3 solution and water, followed by drying over anhydrous Na 2 SO 4 .
AcOEt was distilled off. The residue was dissolved in CHCl 3 -MeOH, and purified by silica-gel column chromatography to obtain the desired compound as an oily product.
Yield: 22 g
R f 1 : 0.61, R f 2 : 0.77
[α] D : -37.1° (c=1.0, DMF)
(2) Boc-Ser (Bzl)-Pro-Arg(NO 2 )-OBzl
22 g of Boc-Pro-Arg(NO 2 )-OBzl was placed in 110 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the the solvent was distilled off.
After drying under reduced pressure, the residue was dissolved in 150 ml of DMF. To the solution, 9 ml of Et 3 N, 12.8 g of Boc-Ser(Bzl)-OH, 10 g of HOBt and 9.4 g of DCC were added under chilling with ice, followed by stirring for 18 hours at room temperature.
DCUrea was removed by filtration, and DMF was distilled off. The residue was dissolved in AcOEt. Then the AcOEt solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl and water, followed by drying over anhydrous Na 2 SO 4 .
AcOEt was distilled off, and the residue was treated with AcOEt-ether to give the desired compound as a crystalline product.
Yield: 21 g
M.P. : 80°-82° C.
R f 1 : 0.67, R f 2 : 0.83
[α] D : -30.8° (c=1.0, DMF)
(3) Boc-Asn-Ser(Bzl)-Pro-Arg(NO 2 ) -OBzl
4.0 g of Boc-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl was placed in 20 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the solvent was distilled off.
To the residue, 2-butanol-CH 2 Cl 2 (5:1 v/v) and saturated aqueous NaHCO 3 solution was added. The organic portion was collected and washed with saturated aqueous NaCl solution, followed by drying over anhydrous Na 2 SO 4 .
The solution was distilled off, and the residue was dissolved in 60 ml of DMF. To the solution, 1.34 g of Boc-Asn-OH, 1.34 g of HOBt and 1.32 g of DCC were added under chilling with ice.
After stirring for 18 hours at room temperature, DCUrea was removed by filtration, and DMF was distilled off.
The residue was dissolved in 2-butanol-CH 2 Cl 2 (5:1 v/v) and then the solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl saturated with NaCl and saturated aqueous NaCl solution, followed by drying over anhydrous Na 2 SO 4 .
The solvent was distilled off, and to the residue was added AcOEt to obtain the desired compound as a crystalline product.
Yield: 4.3 g
M.P. : 186°-187° C.
R f 1 : 0.55, R f 2 : 0.73
[α] D : -34.6° (c=1.0, DMF)
(4) Z-Pro-Asn-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl
3.5 g of Boc-Asn-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl was placed in 15 ml of 4 N HCl-AcOEt for 30 min. at room temperature, and then the solvent was distilled off.
After drying under reduced pressure, the residue was dissolved in DMF. To the solution, 0.8 ml of NMM and 1.52 g of Z-Pro-OSu were added under chilling with ice, followed by stirring for 18 hours at room temperature.
DMF was distilled off. The residue was dissolved in 2-butanol CH 2 Cl 2 (5:1 v/v) and then the solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl saturated with NaCl and saturated aqueous NaCl solution, followed by drying over anhydrous Na 2 SO 4 .
The solvent was distilled off, and the residue was purified with CHCl 3 -methanol by silica-gel column chromatography, then was treated with ether to give the desired compound as a crystalline product.
Yield: 3.2 g
M.P. : 94°-96° C.
R f 1 : 0.55, R f 2 : 0.75
[α] D : -45.5° (C=1.0, DMF)
(5) H-Pro-Asn-Set-Pro-Arg-OH acetate
A solution of 150 mg of Z-Pro-Asn-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl in 20 ml of 80% acetic acid was stirred for 18 hours in a stream of hydrogen gas in the presence of 10% palladium-carbon.
The palladium-carbon was removed by filtration, and the solvent was distilled off. The residue was dissolved in water, then freeze-dried.
Then the resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 96 mg
R f 3 : 0.10
[α] D : -91.0° (c=0.5, water)
FAB mass spectrum (M+1) : 570
EXAMPLE 27
H-Pro-Ser-Pro-Arg-OH acetate
(1) Z-Pro-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl
The desired compound was prepared from 4.0 g of Boc-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl, 20 ml of 4 N HCl-AcOEt, 1 ml of NMM and 2.2 g of Z-Pro-OSu in the same manner as in Example 26-(4). The ether treatment was performed to obtain the desired compound as a crystalline product.
Yield: 4.9 g
M.P. : 72°-74° C.
R f 1 : 0.66, R f 2 : 0.82
[α] D : -45.8° (c=1.0, DMF)
(2) H-Pro-Set-Pro-Arg-OH acetate
150 mg of Z-Pro-Ser(Bzl)-Pro-Arg(NO 2 )-OBzl was reduced in the presence of palladium-carbon in the same manner as in Example 26-(5). The resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 75 mg
R f 3 : 0.13
[α] D : -97.4° (c=0.5, water)
FAB mass spectrum (M+1) : 456
EXAMPLE 28
H-Pro-Set-Pro-Arg-Gly-NH 2 acetate
(1) Boc-Arg(NO 2 )-Gly-NH 2
To a solution of 10 g of Boc-Arg(NO 2 )-OH in 80 ml of DMF, 3.5 ml of NMM and 3.1 ml of ethyl chlorocarbonate were added under chilling with ice, followed by stirring for 15 minutes.
To the resulting solution, a mixture of 3.5 g of H-Gly-NH 2 hydrochloride and 3.5 ml of NMM in 20 ml of DMF was added, and then the resulting mixture was stirred for 3 hours under chilling with ice.
DMF was distilled off. The residue was dissolved in 2-butanol-CH 2 Cl 2 (5:1 v/v) and then the solution was washed successively with saturated aqueous NaHCO 3 solution, dilute HCl saturated with NaCl and saturated NaCl aqueous solution, followed by drying over anhydrous Na 2 SO 4 .
The solvent was distilled off, and to the residue was added AcOEt to obtain the desired compound as a crystalline product.
Yield: 7.4 g
M.P. : 160°-162° C.
R f 1 : 0.21, R f 2 : 0.42
[α] D : +3.2° (c=1.0, DMF)
(2) Boc-Pro-Arg(NO 2 )-Gly-NH 2
The desired compound was prepared from 6.0 g of Boc-Arg(NO 2 )-Gly-NH 2 , 40 ml of 4 N HCl-AcOEt, 3.4 ml of Et 3 N and 5.1 g of Boc-Pro-OSu in the same manner as in Example 26-(4).
Yield: 6.5 g
M.P. 109°-111° C.
R f 1 : 0.23, R f 2 : 0.45
[α] D : -30.5° (c=1.0, DMF)
(3) Boc-Ser(Bzl)-Pro-Arg(NO 2 )-Gly-NH 2
The desired compound was prepared from 6.0 g of Boc-Pro-Arg(NO 2 )-Gly-NH 2 , 35 ml of 4 N HCl-AcOEt, 1.8 ml of Et 3 N and 5.1 g of Boc-Ser(Bzl)-OSu in the same manner as in Example 26-(4).
Yield: 6.7 g
M.P. : 109°-113° C.
R f 1 : 0.32, R f 2 : 0.56
[α] D : -29.2° (c=1.0, DMF)
(4) Z-Pro-Ser(Bzl)-Pro-Arg(NO 2 )-Gly-NH 2
The desired compound was prepared from 1.0 g of Boc-Ser(Bzl)-Pro-Arg(NO 2 )-Gly-NH 2 , 10 ml of 4 N HCl-AcOEt, 0.34 ml of NMM and 0.54 g of Z-Pro-OSu in the same manner as in Example 26-(4).
Yield: 0.7 g
M.P. : 108°-111° C.
R f 1 : 0.34, R f 2 : 0.56
[α] D : -56.0° (c=1.0, DMF)
(5) H-Pro-Ser-Pro-Arg-Gly-NH 2 acetate
150 mg of Z-Pro-Set(Bzl)-Pro-Arg(NO 2 )-Gly-NH 2 was reduced in the presence of palladium-carbon in the same manner as in Example 26-(5). The resulting product was purified by high-performance liquid chromatography at 12 ml/min. (flow rate), 0 to 10% (B) 20 min. linear gradient (A) (mobile phase), subjected to Dowex 1×2 (acetate type) treatment and freeze-dried to obtain the desired compound.
Yield: 105 mg
R f 3 : 0.10
[α] D : -96.7° (c=0.5, water)
FAB mass spectrum (M+1) : 512
An example of pharmacological test showing the effectiveness of the peptides and the peptide derivatives of the present invention is set forth below.
Pharmacological Test: Examination on improvement effect of experimental retrograde amnesia by
The effect of peptides and the peptide derivatives of the present invention on memory consolidation was evaluated by conducting one-trial passive avoidance experiment using male Wistar rats in accordance with the method described by Burbach et al., Science, vol. 221, pp. 1310-1312, 1983. The apparatus consisted of an illuminated room and a dark room, and their floors were made of stainless-steel grid. The rats placed in the illuminated room could freely enter the dark room. Upon entering the dark room the rats received an electro-shock. Retention of passive avoidance behavior to the electro-shock was determined by the measurement of a response latent period, i.e. period required for the rat experienced the electro-shock to reenter the dark room from the time on which the rat was placed in the illuminated room after predetermined intervals.
The rats received an electro-shock (0.5 mA) after one hour from the administration of the peptides of the present invention or a physiological saline solution. Immediately after receiving the electro-shock, the rats were treated with 2.7 to 3.0 mG/kg of cycloheximide or the saline solution by subcutaneous injection. At 48 hours after the administration was made, memory retention of the rats were tested. The rats administered with only the physiological saline solution showed the response latent period of approx. 300 seconds, and those rats of control Group administered with cycloheximide alone showed the response latent period of approx. 50 seconds, which revealed retrograde amnesia.
The average response latent period of rats administered with each peptide of the present invention was compared with that of the control group. Six to eight rats were used for each group to be tested. The response latent period was measured up to a maxime of 600 seconds.
The dose and the effect (the ratio of response latent period of each group to that of the control Groups, shown as %) of the peptides obtained in each example are set forth in Table 1.
TABLE 1______________________________________Compound Dose (ng/kg) Effect (%)______________________________________Example 5 1 298Example 6 1 239Example 9 1 460Example 12 1 235Example 16 1 251Example 17 1 365Example 21 0.1 353Example 27 0.1 213______________________________________
As readily apparent from the above experimental results, the peptides and the peptide derivatives of the invention showed superior effect on improving retrograde amnesia.
Preparation examples of pharmaceuticals containing the peptide derivatives of the present invention are shown below.
Preparation Example 1 (Injection)
To 100 ml of a distilled water for injection were added 0.1 mg of the peptide derivative obtained in Example 1 and 0.9 g of NaCl to prepare an aqueous solution whose pH was adjusted to 6.0 to 8.0 with NaOH. The solution was filtered under sterile condition, and the filtrate was filled up into 1 ml ampul. The ampul was fused to seal under sterile condition by heating to prepare an agent for injection.
With respect to each of the peptides obtained in Examples 7, 12, 15, 21 and 26, the above-described procedure was repeated to prepare agents for injection containing each peptide.
Preparation Example 2 (Freeze-Dried Agent)
To 100 ml of a distilled water for injection were added 5 mg of the peptide derivative obtained in Example 1 and 5 g of D-mannitol to prepare an aqueous solution whose pH was adjusted to 6.0 to 8.0 with a phosphate buffer. The solution was filtered under sterile condition, and the filtrate was divided into a plurality of 1 ml vials. The divided portions were freeze-dried to prepare a freeze-dried agent for injection.
With respect to each of the peptides obtained in Examples 7, 12, 15, 21 and 26, the above-described procedure was repeated to prepare freeze-dried agents for injection containing each peptide.
Preparation Example 3 (Collunarium)
To 100 ml of a physiological saline solution was added 10 mg of the peptide derivative obtained in Example 1. The pH of the mixture was adjusted to 3.0 to 6.0 with a citric acid buffer to prepare a collunarium which contains 50 μg of the peptide of the invention in a dose of 0.5 ml.
With respect to each of the peptides obtained in Examples 7, 12, 15, 21 and 26, the above-described procedure was repeated to prepare collunariums containing each peptide.
Preparation Example 4 (Suppository)
To 98.5 g of hard fat (triglyceride of saturated fatty acid) was added 0.5 g of egg york lecithin. The mixture was melted at temperature of 40° to 45° C. and to the melted mixture was added under stirring a solution of 5 mg of the peptide derivative obtained in Example 1 in 1 g of PEG 400. The resulting dispersion (1 g) was filled into the mold for suppository. The content was removed from the mold after being caked to prepare a suppository.
With respect to each of the peptides obtained in Examples 7, 12, 15, 21 and 26, the above-described procedure was repeated to prepare suppositories containing each peptide. | Disclosed is a novel peptide having one of the formulae: ##STR1## (A and B are the amino acids: wherein if A is D- or L-Pro, B is Hat or Cit;
if A is D-Pro, B is D-Arg, and
if B is D- or L-Arg, A is Sat, Pip, Aze or Arg)
Asn-A-L- (D-)Pro-Arg- (Gly)n (A is Set, Thr or Ala, n is 1 or 0)
A-Ser-Pip-Arg (A is Pro-Asn-, Asn- or Pro-) ##STR2## (A is cyclopentylcarbonyl, Pro or pGlu; B is Gly or β-Ala, W is a hydrogen atom or a group having the formula:
or a peptide having the formula: ##STR3## wherein A and B have the same meanings as mentioned above, respectively pGlu-Asn-Ser-A-B-(Gly)n (A is Aze, D- or L-Pro, Pip or Sat, B is D- or L-Arg, Cit, Hat, Lys or Orn, n is 1 or 0) and
Pro- (Ash)m-Set-L- (D-)Pro-Arg- (Gly) n (m and n are independently 0 or 1)
their functional derivatives, and pharmaceutically acceptable salts thereof. | 2 |
BACKGROUND OF THE INVENTION
[0001] The present invention describes an environment-friendly and economic process for preparing azo colorants.
[0002] In the context of the present invention, azo colorants are those azo dyes and azo pigments that are prepared by azo coupling reaction from a diazonium salt and a CH-acidic compound, referred to inter alia as coupling component hereinbelow (Ullmann's Encyclopedia of Industrial Chemistry, Sixth Edition, “Azo Dyes” and “Azo Pigments”; and DIN 55943). Industrially, they are conventionally prepared by the batch process. Descriptions have also been given of continuous mixing processes in mixing nozzles and continuous flow reactors (in EP-A-0 244 686, for example).
[0003] A feature common to these processes is the need for precise monitoring and control of the process parameters: for example, temperature, time, mixing, and colorant concentration-the suspension concentration in the case of azo pigments, for example-are critical to the yield, quality consistency, and coloristic and fastness properties of the resulting azo colorants. In addition, in the case of batch processes, the scaleup of new products from laboratory to industrial scales is complex and may cause difficulties, since, for example, tank and stirrer geometries or heat transitions may greatly affect the azo pigment particle size and its distribution, and the coloristic properties.
[0004] It was an object of the present invention to find an environment-friendly, economic, technically reliable, and cost-effective process for preparing azo colorants by the azo coupling reaction, said process being universally suitable for the preparation both of azo pigments and of azo dyes; providing optimum mixing of the reactants; being combinable where appropriate with the measures known in connection with the preparation of azo colorants, such as the use of solvents or auxiliaries; permitting the desired process parameters to be maintained very constantly; and allowing easy scaleup.
[0005] The conduct of certain chemical reactions in microreactors is known (from DE-A-3 926 466, for example). Microreactors are constructed, for example, from stacks of grooved plates with microchannels and are described in DE 39 26 466 C2 and U.S. Pat. No.5,534,328. U.S. Pat. No. 5,811,062 notes that microreactors are used preferentially for reactions which do not require or produce solids, since the microchannels easily become clogged.
SUMMARY OF THE INVENTION
[0006] It has now been found that the object of the invention may be achieved, surprisingly, through the use of a microjet reactor.
[0007] The present invention provides a process for preparing azo colorants which comprises spraying the reactants, i.e. the coupling component and the diazonium salt, in their solution or suspension form through nozzles to a point of conjoint collision in a reactor chamber enclosed by a housing in a microjet reactor, appropriately via one or more pumps, preferably high-pressure pumps, a gas or an evaporating liquid being passed into the reactor chamber through an opening in the housing for the purpose of maintaining a gas atmosphere in the reactor chamber, especially at the point of collision of the jets, and where appropriate of effecting cooling as well, and the resulting product solution or suspension and the gas or the evaporated liquid being removed from the reactor through a further opening in the housing by means of overpressure on the gas entry side or underpressure on the product and gas exit side.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0008] Preparation of azo colorants in accordance with the invention requires intensive, rapid, uniform, and reproducible mixing of the reactants. This is brought about by spraying the reactants used into the reactor chamber under a pressure of at least 10 bar, preferably at least 50 bar, in particular from 50 to 5 000 bar.
[0009] In order to prevent material wear on the inner surfaces of the housing, the collision point is shifted into the material-remote gas space. By “material-remote” here is meant that, in the vicinity of the collision point of the jets, a gas atmosphere is maintained by means of the introduced gas or evaporating liquid. This means that the collision point at which the jets impinge on one another is not sited on a vessel wall or on a pipe wall. This prevents the material wear that would occur at the point where cavitation takes place on material walls. Cavitation occurs particularly when using high pressures, especially at pressures above 3 000 bar. Moreover, the colliding jets are not braked by the gas atmosphere prior to their collision, as would be the case, for example, if they had to pass through a liquid.
[0010] The material of the nozzles should be as hard and thus low-wearing as possible; examples of suitable materials include ceramics, such as oxides, carbides, nitrides or mixed compounds thereof, with preference being given to the use of aluminum oxide, particularly in the form of sapphire or ruby, although diamond is also particularly suitable. Suitable hard substances also include metals, especially hardened metals. The bores of the nozzles have diameters of less than 2 mm, preferably less than 0.5 mm and in particular less than 0.4 mm.
[0011] The microjet reactor may be configured in principle as a two-jet, three-jet or multijet reactor, preference being given to the two-jet configuration. In the case of an arrangement with two jets, the jets preferably strike one another frontally (180° angle between the jets); in the case of a three-jet arrangement, an angle of 120° between the jets is appropriate. The jets advantageously may be mounted in a device which can be adjusted to the point of conjoint collision. As a result of these different embodiments it is possible, for example, to realize different volume ratios of the diazonium salt and coupling component solutions or suspensions which are required for the reaction.
[0012] In one particularly preferred embodiment of the process of the invention, the coupling component solution or suspension and the diazonium salt solution or suspension are sprayed against one another frontally through two opposed nozzles by means of two high-pressure pumps. A further particularly preferred embodiment of the process of the invention is a three-jet reactor in which, for example, by means of a high-pressure pump the diazonium salt solution or suspension is sprayed to the point of conjoint collision through one nozzle and by means of a second high-pressure pump the coupling component solution or suspension is sprayed to the same point through two nozzles.
[0013] In another preferred embodiment, the diazonium salt or suspension is sprayed to a point of conjoint collision through 1, 2 or more nozzles, preferably through one nozzle, and independently thereof the coupling component solution or suspension is sprayed to the same point through 1, 2 or more nozzles, preferably through 1, 2 or 3 nozzles.
[0014] The nozzle of the diazonium salt solution or suspension and that of the coupling component solution or suspension may have different diameters. The nozzle through which the diazonium salt is sprayed appropriately has a diameter which is from 0.2 to 5 times, preferably from 0.3 to 3 times, that of the nozzle through which the coupling component is sprayed.
[0015] The temperatures of the reactants are normally from −10 to +90° C., preferably from −5 to +80° C., particularly from 0 to 70° C. It is also possible to operate under pressure at above the boiling point of the liquid medium.
[0016] Where necessary, the introduced gas or the evaporating liquid that is used to maintain the gas atmosphere in the inside of the housing may be used for cooling. Additionally, an evaporating cooling liquid or a cooling gas may be introduced into the reactor chamber by way of an additional bore in the housing. The aggregate state of the cooling medium may be conditioned by temperature and/or pressure. The medium in question may comprise, for example, air, nitrogen, carbon dioxide or other, inert gases or liquids having an appropriate boiling point under increased pressure. It is possible here for the transition of the cooling medium from the liquid to the gaseous state to take place in the reactor itself by virtue of the fact that heat released in the course of the precipitation brings about the change in aggregate state. It is also possible for the evaporative cooling of an expanding gas to be utilized for cooling.
[0017] The housing enclosing the reactor chamber may also be constructed in such a way that it is thermostatable and may be used for cooling; or else the product may be cooled after it has exited the housing. The pressure in the reactor chamber may, for example, be set and maintained by means of a pressure maintenance valve, so that the gas used is present in the liquid or supercritical or subcritical state. Thus it is possible, for example, to utilize the evaporative cooling of a gas.
[0018] If operation is to take place at elevated temperature, the energy required for heating may be supplied prior to the emergence from the nozzles of the reactants-for example, in the supply lines—or by way of the thermostatable housing or the introduced gas. In principle, owing to the high pressures in the high-pressure lances, the chosen temperature may also be situated a considerable way above the boiling point of the liquid medium. Suitable liquid media therefore include those which, at the temperature of reaction in the interior of the housing under atmospheric pressure, are present as gases. The reactants may also differ in temperature.
[0019] The process of the invention is suitable for all azo colorants which can be prepared by azo coupling reaction: for example, for azo pigments from the series of the monoazo pigments, disazo pigments, β-naphthol and Naphtol AS pigments, laked azo pigments, benzimidazolone pigments, disazo condensation pigments and metal complex azo pigments; and for azo dyes from the series of the cationic, anionic, and nonionic azo dyes, especially monoazo, disazo and polyazo dyes, formazan dyes and other metal complex azo dyes, and anthraquinone azo dyes.
[0020] The process of the invention also relates to the preparation of precursors of the actual azo colorants by azo coupling reaction. By means of the process of the invention it is possible, for example, to prepare precursors for laked azo colorants, i.e., lakeable azo colorants, for diazo condensation pigments, i.e., monoazo colorants which can be linked via a bifunctional group or, for example, disazo colorants which can be extended via an acid chloride intermediate, for formazan dyes, or other heavy metal azo dyes, examples being copper, chromium, nickel or cobalt azo dyes, i.e., azo colorants which can be complexed with heavy metals (see also “The Chemistry of Synthetic Dyes”, K. Venkataraman, Academic Press).
[0021] The azo dyes comprise in particular the alkali metal salts or ammonium salts of the reactive dyes and also of the acid wool dyes or substantive cotton dyes of the azo series. Azo dyes under consideration include preferably metal-free and metalizable monoazo, disazo, and polyazo dyes, and azo dyes containing one or more sulfonic acid groups.
[0022] Among the azo colorants which can be prepared by the process of the invention, and the azo colorant precursors which can be prepared by the process of the invention, the compounds involved in the case of the azo pigments include in particular C.I. Pigment Yellow 1, 3, 12, 13, 14, 16, 17, 65, 73, 74, 75, 81, 83, 97, 98, 106, 111, 113, 114, 120, 126, 127, 150, 151, 154, 155, 174, 175, 176, 180, 181, 183, 191, 194, 198, 213; Pigment Orange 5, 13, 34, 36, 38, 60, 62, 72, 74; Pigment Red 2, 3, 4, 8, 9, 10, 12, 14, 22, 38, 48:1-4, 49:1, 52:1-2, 53:1-3, 57:1, 60, 60:1, 68, 112, 137, 144, 146, 147, 170, 171, 175, 176, 184, 185, 187, 188, 208, 210, 214, 242, 247, 253, 256, 262, 266; Pigment Violet 32; Pigment Brown 25; and, if desired, their precursors which are prepared by azo coupling reaction.
[0023] In the case of the azo dyes, the compounds involved comprise, in particular, C.I. Reactive Yellow 15, 17, 23, 25, 27, 37, 39, 42, 57, 82, 87, 95, 111, 125, 142, 143, 148, 160, 161, 165, 168, 176, 181, 205, 206, 207, 208; Reactive Orange 7, 11, 12, 13, 15, 16, 30, 35, 64, 67, 69, 70, 72, 74, 82, 87, 91, 95, 96, 106, 107, 116, 122, 131, 132, 133; Reactive Red 2, 21, 23, 24, 35, 40, 49, 55, 56, 63, 65, 66, 78, 84, 106, 112, 116, 120, 123, 124, 136, 141, 147, 152, 158, 159, 174, 180, 181, 183, 184, 190, 197, 200, 201, 218, 225, 228, 235, 238, 239, 242, 243, 245, 264, 265, 266, 267, 268, 269; Reactive Violet 2, 5, 6, 23, 33, 36, 37; Reactive Blue 19, 28, 73, 89, 98, 104, 113, 120, 122, 158, 184, 193, 195, 203, 213, 214, 225, 238, 264, 265, 267; Reactive Green 32; Reactive Brown 11, 18, 19, 30, 37; Reactive Black 5, 13, 14, 31, 39, 43; Disperse Yellow 3, 23, 60, 211, 241; Disperse Orange 1:1, 3, 21, 25, 29, 30, 45, 53, 56, 80, 66, 138, 149; Disperse Red 1, 13, 17, 50, 56, 65, 82, 106, 134, 136, 137, 151, 167, 167:1, 169, 177, 324, 343, 349, 369, 376; Disperse Blue 79, 102, 125, 130, 165, 165:1, 165:2, 287, 319, 367; Disperse Violet 40, 93, 93:1, 95; Disperse Brown 1,4:1; Basic Yellow 19; Basic Red 18, 18:1, 22, 23, 24, 46, 51, 54, 115; Basic Blue 41, 149; Mordant Yellow 8, 30; Mordant Red 7, 26, 30, 94; Mordant Blue 9, 13, 49; Mordant Brown 15; Mordant Black 7, 8, 9, 11, 17, 65; Acid Yellow 17, 19, 23, 25, 59, 99, 104, 137, 151, 155, 169, 197, 219, 220, 230, 232, 240, 242, 246, 262; Acid Orange 7, 67, 74, 94, 95, 107, 108, 116, 162, 166; Acid Red 1, 14, 18, 27, 52, 127, 131, 151, 154, 182, 183, 194, 195, 211, 249, 251, 252, 260, 299, 307, 315, 316, 337, 360, 361, 405, 407, 414, 425, 426, 439, 446, 447; Acid Blue 113, 156, 158, 193, 199, 229, 317, 351; Acid Green 73, 109; Acid Brown 172, 194, 226, 289, 298, 413, 415; Acid Black 24, 52, 60, 63, 63:1, 107, 140, 172, 207, 220; Direct Yellow 27, 28, 44, 50, 109, 110, 137, 157, 166, 169; Direct Orange 102, 106; Direct Red 16, 23, 79, 80, 81, 83, 83:1, 84, 89, 212, 218, 227, 239, 254, 262, 277; Direct Violet 9, 47, 51, 66, 95; Direct Blue 71, 78, 94, 98, 225, 229, 244, 290, 301, 312; Direct Green 26, 28, 59; Direct Black 19, 22, 51, 56, 112, 113, 122; and, if desired, their precursors prepared by azo coupling reaction.
[0024] In the process of the invention, it is appropriate to supply the reactants in the form of aqueous solutions or suspensions, and preferably in equivalent amounts, to the microjet reactor.
[0025] The azo coupling reaction takes place preferably in aqueous solution or suspension, although it is also possible to use organic solvents, alone or as a mixture with water; by way of example, alcohols having from 1 to 10 carbon atoms, examples being methanol, ethanol, n-propanol, isopropanol, butanols, such as n-butanol, sec-butanol, and tert-butanol, pentanols, such as n-pentanol and 2-methyl-2-butanol, hexanols, such as 2-methyl-2-pentanol and 3-methyl-3-pentanol, 2-methyl-2-hexanol, 3-ethyl-3-pentanol, octanols, such as 2,4,4-trimethyl-2-pentanol, and cyclohexanol; or glycols, such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, or glycerol; polyglycols, such as polyethylene glycols or polypropylene glycols; ethers, such as methyl isobutyl ether, tetrahydrofuran or dimethoxyethane; glycol ethers, such as monomethyl or monoethyl ethers of ethylene glycol or propylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, butyl glycols or methoxybutanol; ketones, such as acetone, diethyl ketone, methylisobutyl ketone, methyl ethyl ketone or cyclohexanone; aliphatic acid amides, such as formamide, dimethylformamide, N-methylacetamide or N,N-dimethylacetamide; urea derivatives, such as tetramethylurea; or cyclic carboxamides, such as N-methylpyrrolidone, valerolactam or caprolactam; esters, such as carboxylic acid C 1 -C 6 alkyl esters, such as butyl formate, ethyl acetate or propyl propionate; or carboxylic acid C 1 -C 6 glycol esters; or glycol ether acetates, such as 1-methoxy-2-propyl acetate; or phthalic or benzoic acid C 1 -C 6 alkyl esters, such as ethyl benzoate; cyclic esters, such as caprolactone; nitriles, such as acetonitrile or benzonitrile; aliphatic or aromatic hydrocarbons, such as cyclohexane or benzene; or alkyl-, alkoxy-, nitro- or halo-substituted benzene, such as toluene, xylenes, ethylbenzene, anisole, nitrobenzene, chlorobenzene, o-dichlorobenzene, 1,2,4-trichlorobenzene or bromobenzene; or other substituted aromatics, such as benzoic acid or phenol; aromatic heterocycles, such as pyridine, morpholine, picoline or quinoline; and also hexamethylphosphoramide, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide, and sulfolane. Said solvents may also be used as mixtures. Preference is given to using water-miscible solvents.
[0026] Reactants used for the azo coupling reaction are diazonium salts of aromatic or hetaromatic amines, such as, for example, aniline, 2-methyl anthranilate, 2,5-dichloroaniline, 2-methyl-4-chloroaniline, 2-chloroaniline, 2-trifluoromethyl-4-chloroaniline, 2,4,5-trichloraniline; 3-amino-4-methylbenzamide, 2-methyl-5-chloroaniline, 4-amino-3-chloro-N′-methylbenzamide, o-toluidine, o-dianisidine, 2,2′,5,5′-tetrachlorobenzidine, 2-amino-5-methylbenzenesulfonic acid, and 2-amino-4-chloro-5-methylbenzenesulfonic acid.
[0027] Of particular interest for azo pigments are the following amine components:
[0028] 4-methyl-2-nitrophenylamine, 4-chloro-2-nitrophenylamine, 3,3′-dichlorobiphernyl-4,4′-diamine, 3,3′-dimethylbiphenyl-4,4′-diamine, 4-methoxy-2-nitrophenylamine, 2-methoxy-4-nitrophenylamine, 4-amino-2,5-dimethoxy-N-phenylbenzenesulfonamide, dimethyl 5-aminoisophthalate, anthranilic acid, 2-trifluoromethylphenylamine, dimethyl 2-aminoterephthalate, 1,2-bis(2-aminophenoxy)ethane, 2-amino-4-chloro-5-methylbenzenesulfonic acid, 2-methoxyphenylamine, 4-(4-aminobenzoyl-amino)benzamide, 2,4-dinitrophenylamine, 3-amino-4-chlorobenzamide, 3-amino-4-chlorobenzoic acid, 4-nitrophenylamine, 2,5-dichlorophenylamine, 4-methyl-2-nitrophenylamine, 2-chloro-4-nitrophenylamine, 2-methyl-5-nitrophenylamine, 2-methyl-4-nitrophenylamine, 2-methyl-5-nitrophenylamine, 2-amino-4-chloro-5-methylbenzenesulfonic acid, 2-aminonaphthalene-1-sulfonic acid, 2-amino-5-chloro-4-methylbenzenesulfonic acid, 2-amino-5-chloro-4-methylbenzenesulfonic acid, 2-amino-5-methylbenzenesulfonic acid, 2,4,5-trichlorophenylamine, 3-amino-4-methoxy-N-phenylbenzamide, 4-aminobenzamide, methyl 2-aminobenzoate, 4-amino-5-methoxy-2,N-dimethylbenzenesulfonamide, monomethyl 2-amino-N-(2,5-dichlorophenyl) terephthalate, butyl 2-aminobenzoate, 2-chloro-5-trifluoromethyl-phenylamine, 4-(3-amino-4-methylbenzoylamino) benzenesulfonic acid, 4-amino-2,5-dichloro-N-methylbenzenesulfonamide, 4-amino-2,5-dichloro-N, N-dimethyl-benzenesulfonamide, 6-amino-1 H-quinazoline-2,4-dione, 4-(3-amino-4-methoxy-benzoylamino) benzamide, 4-amino-2,5-dimethoxy-N-methylbenzenesulfonamide, 5-aminobenzimidazolone, 6-amino-7-methoxy-1,4-dihydroquinoxaline-2,3-dione, 2-chloroethyl 3-amino-4-methylbenzoate, isopropyl 3-amino-4-chlorobenzoate, 3-amino-4-chlorobenzotrifluoride, n-propyl 3-amino-4-methylbenzoate, 2-aminonaphthalene-3,6,8-trisulfonic acid, 2-aminonaphthalene-4,6,8-trisulfonic acid, 2-aminonaphthalene-4,8-disulfonic acid, 2-aminonaphthalene-6,8-disulfonic acid, 2-amino-8-hydroxynaphthalene-6-sulfonic acid, 1-amino-8-hydroxy-naphthalene-3,6-disulfonic acid, 1-amino-2-hydroxybenzene-5-sulfonic acid, 1-amino-4-acetylaminobenzene-2-sulfonic acid, 2-aminoanisole, 2-aminomethoxybenzene-ω-methanesulfonic acid, 2-aminophenol-4-sulfonic acid, o-anisidine-5-sulfonic acid, 2-(3-amino-1,4-dimethoxybenzenesulfonyl) ethyl sulfate, and 2-(1-methyl-3-amino-4-methoxybenzenesulfonyl) ethyl sulfate.
[0029] The following amine components are of particular interest for azo dyes:
[0030] 2-(4-aminobenzenesulfonyl)ethyl sulfate, 2-(4-amino-5-methoxy-2-methylbenzene-sulfonyl) ethyl sulfate, 2-(4-amino-2,5-dimethoxybenzenesulfonyl) ethyl sulfate,
[0031] 2-[4-(5-hydroxy-3-methylpyrazol-1-yl)benzenesulfonyl]ethyl sulfate, 2-(3-amino-4-methoxybenzenesulfonyl)ethyl sulfate, and 2-(3-aminobenzenesulfonyl) ethyl sulfate.
[0032] The following coupling components are of particular interest for azo pigments:
[0033] acetoacetarylides of the formula (I)
[0034] where
[0035] n is a number from 0 to 3, and
[0036] R 1 can be a C 1 -C 4 -alkyl group, such as methyl or ethyl; a C 1 -C 4 -alkoxy group, such as methoxy or ethoxy; a trifluoromethyl group; a nitro group; a halogen atom such as fluorine, chlorine or bromine; a NHCOCH 3 group; an SO 3 H group; a group SO 2 NR 10 R 11 where R 10 and R 11 are identical or different and are hydrogen or C 1 -C 4 alkyl; a group COOR 10 where R 10 is as defined above; or a group COONR 12 R 13 where R 11 and R 13 independently are hydrogen, C 1 -C 4 alkyl or phenyl, the phenyl ring being substituted by one, two or three identical or different substituents from the group consisting Of C 1 -C 4 alkyl, C 1 -C 4 alkoxy, trifluoromethyl, nitro, halogen, COOR 10 , R 10 being as defined above, and COONR 10 R 11 , R 10 and R 11 being identical or different and being as defined above,
[0037] and where n>1 R 1 may be identical or different;
[0038] 2-hydroxynaphthalenes of the formula (II),
[0039] where
[0040] X is hydrogen, a COOH group or a group of the formula (III), (VI) or (VII);
[0041] where n and R 1 are as defined above; and
[0042] R 20 is hydrogen, methyl or ethyl;
[0043] Bisacetoacetylated diaminophenyls and -biphenyls, N,N′-Bis(3-hydroxy-2-naphthoyl) phenylenediamines, in which the phenyl or biphenyl ring system may be unsubstituted or substituted by 1, 2, 3 or 4 identical or different radicals CH 3 , C 2 H 5 , OCH 3 , OC 2 H 5 , NO 2 , F, Cl, CF 3 ;
[0044] Acetoacetarylides of dinuclear heterocycles of the formula (IV),
[0045] where n and R 1 are as defined above,
[0046] Q 1 , Q 2 and Q 3 may be identical or different and are N, NR 2 , CO, N—CO, NR 2 —CO, CO—N, CO—NR 2 , CH, N—CH, NR 2 —CH, CH—N, CH—NR 2 , CH 2 , N—CH 2 , NR 2 —CH 2 , CH 2 —N, CH 2 —NR or SO 2 , where
[0047] R 2 is a hydrogen atom; is a C 1 -C 4 alkyl group, such as methyl or ethyl; or is a phenyl group which may be unsubstituted or substituted one or more times by halogen, C 1 -C 4 alkyl, C 1 -C 4 alkoxy, trifluoromethyl, nitro, cyano,
[0048] with the proviso that the combination of Q 1 , Q 2 and Q 3 with the two carbon atoms of the phenyl ring results in a saturated or unsaturated, five- or six-membered ring;
[0049] preferably acetoacetarylides of the formula (VIa) and (VIIa),
[0050] where R 1 and n are as defined above and R 20 is hydrogen, methyl or ethyl;
[0051] and also pyrazolones of the formula (V),
[0052] where
[0053] R 3 is a CH 3 , COOCH 3 or COOC 2 H 5 group,
[0054] R 4 is a CH 3 or SO 3 H group or a chlorine atom, and
[0055] p is a number from 0 to 3,
[0056] and where p>1 R 4 may be identical or different.
[0057] The following coupling components are of particular interest for azo dyes:
[0058] 4-[5-hydroxy-3-methylpyrazol-1-yl]benzenesulfonic acid, 2-aminonaphthalene-1,5-disulfonic acid, 5-methoxy-2-methyl-4-[3-oxobutyrylamino]benzenesulfonic acid, 2-methoxy-5-methyl-4-[3-oxobutyrylamino]benzenesulfonic acid, 4-acetylamino-2-aminobenzenesulfonic acid, 4-[4-chloro-6-(3-sulfophenylamino)-[1,3,5]-triazin-2-amino]-5-hydroxynaphthalene-2,7-disulfonic acid, 4-acetylamino-5-hydroxy-naphthalene-2,7-disulfonic acid, 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid, 5-hydroxy-1 -[4-sulfophenyl]-1H-pyrazole-3-carboxylic acid, 2-aminonaphthalene-6,8-disulfonic acid, 2-amino-8-hydroxynaphthalene-6-sulfonic acid, 1-amino-8-hydroxynaphthalene-3,6-disulfonic acid, 2-aminoanisole, 2-aminomethoxy -benzene-ω-methanesulfonic acid, and 1,3,5-trishydroxybenzene.
[0059] In the process of the invention for preparing azo colorants it is also possible to use the auxiliaries that are employed in the conventional processes, such as surfactants, nonpigmentary and pigmentary dispersants, fillers, standardizers, resins, waxes, defoamers, antidust agents, extenders, shading colorants, preservatives, drying retardants, rheology control additives, wetting agents, antioxidants, UV absorbers, light stabilizers, or a combination thereof. The auxiliaries may be added at any point in time before, during or after the reaction in the microjet reactor, all at once or in several portions. The auxiliaries may, for example, be added prior to injection to the reactant solutions or suspensions, or else during the reaction in liquid, dissolved or suspended form, by means of a separate jet, by injection into the collision point.
[0060] The overall amount of the added auxiliaries may amount to from 0 to 40% by weight, preferably from 1 to 30% by weight, in particular from 2.5 to 25% by weight, based on the azo colorant.
[0061] Suitable surfactants include anionic or anion-active, cationic or cation-active, and nonionic substances or mixtures of these agents. Preference is given to those surfactants or surfactant mixtures which do not foam in the course of the collision.
[0062] Examples of suitable anion-active substances include fatty acid taurides, fatty acid N-methyltaurides, fatty acid isethionates, alkylphenylsulfonates, alkylnaphthalene-sulfonates, alkylphenol polyglycol ether sulfates, fatty alcohol polyglycol ether sulfates, fatty acid amide polyglycol ether sulfates, alkyl sulfosuccinamates, alkenylsuccinic monoesters, fatty alcohol polyglycol ether sulfosuccinates, alkanesulfonates, fatty acid glutamates, alkyl sulfosuccinates, fatty acid sarcosides; fatty acids, such as palmitic, stearic, and oleic acid; soaps, such as alkali metal salts of fatty acids, naphthenic acids and resin acids, such as abietic acid; alkali-soluble resins, examples being rosin-modified maleate resins, and condensation products based on cyanuric chloride, taurine, N,N′-diethylaminopropylamine, and
[0063] p-phenylenediamine. Particular preference is given to resin soaps, i.e., alkali metal salts of resin acids.
[0064] Examples of suitable cation-active substances include quaternary ammonium salts, fatty amine alkoxylates, alkoxylated polyamines, fatty amine polyglycol ethers, fatty amines, diamines and polyamines derived from fatty amines or fatty alcohols, and their alkoxylates, imidazolines derived from fatty acids, and salts of these cation-active substances, such as acetates, for example.
[0065] Examples of suitable nonionic substances include amine oxides, fatty alcohol polyglycol ethers, fatty acid polyglycol esters, betaines, such as fatty acid amide N-propyl betaines, phosphoric esters of aliphatic and aromatic alcohols, fatty alcohols or fatty alcohol polyglycol ethers, fatty acid amide ethoxylates, fatty alcohol-alkylene oxide adducts, and alkylphenol polyglycol ethers.
[0066] By nonpigmentary dispersants are meant substances which structurally are not derived by chemical modification from organic pigments. They are added as dispersants either during the actual preparation of pigments, or else often during the incorporation of the pigments into the application media to be colored; for example in the preparation of paints or printing inks, by dispersion of the pigments into the corresponding binders. They may be polymeric substances, examples being polyolefins, polyesters, polyethers, polyamides, polyimines, polyacrylates, polyisocyanates, block copolymers thereof, copolymers of the corresponding monomers; or polymers of one class modified with a few monomers from another class. These polymeric substances carry polar anchor groups such as hydroxyl, amino, imino, and ammonium groups, for example, carboxylic acid groups and carboxylate groups, sulfonic acid groups and sulfonate groups, or phosphonic acid groups and phosphonate groups, and may also be modified with aromatic, nonpigmentary substances. Nonpigmentary dispersants may also, furthermore, be aromatic substances chemically modified with functional groups and not derived from organic pigments. Nonpigmentary dispersants of this kind are known to the skilled worker, and some are available commercially (e.g., Solsperse®, Avecia; Disperbyk®, Byk, Efka®, Efka). Although several types will be mentioned below to give a representation, it is possible in principle to employ any other substances described, examples being condensation products of isocyanates and alcohols, diols or polyols, amino alcohols or diamines or polyamines, polymers of hydroxycarboxylic acids, copolymers of olefin monomers or vinyl monomers and ethylenically unsaturated carboxylic acids/esters, urethane-containing polymers of ethylenically unsaturated monomers, urethane-modified polyesters, condensation products based on cyanuric halides, polymers containing nitroxyl compounds, polyester amides, modified polyamides, modified acrylic polymers, comb dispersants comprising polyesters and acrylic polymers, phosphoric esters, triazine-derived polymers, modified polyethers, or dispersants derived from aromatic nonpigmentary substances. These basic structures are in many cases modified further, by means for example of chemical reaction with further substances carrying functional groups or by salt formation.
[0067] By pigmentary dispersants are meant pigment dispersants which are derived from an organic pigment as the parent structure and are prepared by chemically modifying this parent structure; examples include saccharin-containing pigment dispersants, piperidyl-containing pigment dispersants, naphthalene-or perylene-derived pigment dispersants, pigment dispersants containing functional groups linked to the pigment parent structure via a methylene group, pigment parent structures chemically modified with polymers, pigment dispersants containing sulfo acid groups, pigment dispersants containing sulfonamide groups, pigment dispersants containing ether groups, or pigment dispersants containing carboxylic acid, carboxylic ester or carboxamide groups.
[0068] Since compliances with a desired pH during and after the reaction is often critical to the quality, it is possible, upstream of the injection nozzles or else by sprayed injection of a separate jet into the collision point, to supply buffer solutions, preferably of organic acids and their salts, such as formic acid/formate buffer, acetic acid/acetate buffer, and citric acid/citrate buffer, for example; or of inorganic acids and their salts, such as phosphoric acid/phosphate buffer or carbonic acid/carbonate or hydrogen carbonate buffer, for example.
[0069] For the reactants, auxiliaries or buffer solutions it is also possible to use different jet reaches or a different number of jets and so to realize, for example, different volume proportions that are required. With the process of the invention it is also possible, through the use of more than one diazonium salt and/or more than one coupling component, to prepare mixtures or else, in the case of solid products, mixed crystals of azo colorants. In this case the reactants may be injected as a mixture or separately.
[0070] The azo colorant is preferably isolated directly following reaction. However, it is also possible to carry out an aftertreatment (finish) with water and/or an organic solvent, at temperatures for example from 20 to 250° C., with or without the addition of auxiliaries.
[0071] It was surprising and was not foreseeable that the environmentally unproblematic preparation of azo colorants would be possible in this simple and technically uncomplicated way through the collision of jets in a microjet reactor. The process of the invention is universally suitable for preparing azo colorants obtained in the form of a suspension or in the form of solution. The very rapid, intensive mixing of the reactants ensures rapid and complete conversion and hence constant and reproducible reaction conditions and the desired consistency of quality. Instances of clogging, such as occur in the case of the existing microreactors where solid substances are used or produced, can be reliably avoided. Scaleup is also easy, since the drastic changes in surface/volume ratios or mixing ratios that commonly occur, for example, are absent.
[0072] Inventively prepared azo colorants, particularly the azo pigments, are suitable for coloring natural or synthetic organic materials of high molecular mass, such as cellulose ethers and cellulose esters, such as ethylcellulose, nitrocellulose, cellulose acetate or cellulose butyrate, for example, natural resins or synthetic resins, such as addition-polymerization resins or condensation resins, examples being amino resins, especially urea-and melamine-formaldehyde resins, alkyd resins, acrylic resins, phenolic resins, polycarbonates, polyolefins, such as polystyrene, polyvinyl chloride, polyethylene, polypropylene, polyacrylonitrile, and polyacrylates, polyamides, polyurethanes or polyesters, rubber, latices, casein, silicones, and silicone resins, individually or in mixtures.
[0073] In this context it is unimportant whether the high molecular mass organic compounds mentioned are in the form of plastically deformable masses, casting resins, pastes, melts or spinning solutions, paints, stains, foams, drawing inks, writing inks, mordants, coating materials, emulsion paints or printing inks. Depending on the intended use it proves advantageous to utilize the azo colorants obtained in accordance with the invention as blends or in the form of preparations or dispersions. Based on the high molecular mass organic material to be colored, the azo colorants prepared in accordance with the invention are employed in an amount of preferably from 0.05 to 30% by weight, more preferably from 0.1 to 15% by weight.
[0074] The azo pigments prepared by the process of the invention may be used for example to pigment the industrially commonplace baking varnishes from the class of alkyd-melamine resin varnishes, acrylic-melamine resin varnishes, polyester varnishes, high-solids acrylic resin varnishes, aqueous, polyurethane-based varnishes, and also two-component varnishes based on polyisocyanate-crosslinkable acrylic resins, and especially automotive metallic varnishes.
[0075] The azo colorants prepared in accordance with the invention are also suitable for use as colorants in electrophotographic toners and developers, such as one- or two-component powder toners (also called one- or two-component developers), magnetic toners, liquid toners, addition-polymerization toners, and also specialty toners.
[0076] Typical toner binders are addition-polymerization, polyaddition, and polycondensation resins, such as styrene, styrene-acrylate, styrene-butadiene, acrylate, polyester, and phenol-epoxy resins, polysulfones, polyurethanes, individually or in combination, and also polyethylene and polypropylene, which may contain further ingredients, such as charge control agents, waxes or flow aids, or may be subsequently modified with these additives.
[0077] Moreover, the azo colorants prepared in accordance with the invention are suitable for use as colorants in powders and powder coating materials, especially in triboelectrically or electrokinetically sprayable powder coating materials that are used to coat the surfaces of articles made, for example, of metal, wood, plastic, glass, ceramic, concrete, textile material, paper or rubber.
[0078] Typical powder coating resins employed are epoxy resins, carboxyl-and hydroxyl-containing polyester resins, polyurethane resins and acrylic resins, together with customary curing agents. Combinations of resins are also used. For example, epoxy resins are frequently used in combination with carboxyl- and hydroxyl-containing polyester resins. Typical curing components (depending on the resin system) are, for example, acid anhydrides, imidazoles, and also dicyandiamide and its derivatives, blocked isocyanates, bisacylurethanes, phenolic and melamine resins, triglycidyl isocyanurates, oxazolines, and dicarboxylic acids.
[0079] Moreover, the azo colorants prepared in accordance with the invention are suitable for use as colorants in inkjet inks on an aqueous and nonaqueous basis, and also in those inks which operate in accordance with the hotmelt process.
[0080] Furthermore, the azo colorants prepared in accordance with the invention are also suitable as colorants for color filters, both for subtractive and for additive color generation.
[0081] The azo colorants prepared in accordance with the invention, particularly the azo dyes, are suitable for dyeing or printing hydroxyl-containing or nitrogenous natural organic and also synthetic substrates. Such substrates include for example synthetic or natural fiber materials and also leather materials comprising predominantly natural or regenerated cellulose or natural or synthetic polyamides. With preference they are suitable for dyeing and printing textile material based on acetate, polyester, polyamide, polyacrylonitrile, PVC, and polyurethane fibers and also wool or in particular cotton. To this end, the dyes may be applied to the textile materials by the usual exhaust, padding or printing processes.
[0082] In order to assess the properties in the coating sector of the pigments prepared in accordance with the present invention, a selection was made, from among the large number of known varnishes, of an alkyd-melamine resin varnish (AM) containing aromatics and based on a medium-oil alkyd resin and a butanol-etherified melamine resin; a polyester varnish (PE) based on cellulose acetobutyrate; a high-solids acrylic resin baking varnish based on a nonaqueous dispersion (HS); and an aqueous, polyurethane-based varnish (PUR).
[0083] The color strength and hue were determined in accordance with DIN 55986.
[0084] The millbase rheology after dispersion was evaluated on the basis of the following five-point scale:
[0085] thin
[0086] fluid
[0087] thick
[0088] slightly set
[0089] set
[0090] Following dilution of the millbase to the final pigment concentration, the viscosity was assessed using the Rossmann viscospatula type 301 from Erichsen.
[0091] Gloss measurements were carried out on case films at an angle of 20° in accordance with DIN 67530 (ASTMD 523) using the “multigloss” gloss meter from Byk-Mallinckrodt.
[0092] The solvent fastness was determined in accordance with DIN 55976.
[0093] The fastness to overcoating was determined in accordance with DIN 53221.
[0094] In the preceding text and in the following examples, parts and percentages are each by weight of the substances so described.
EXAMPLES
Example 1
[0095] An approximately 5% strength aqueous 3,3′-dichlorobenzidene tetraazo solution with a temperature of 0° C., prepared by bisdiazotizing 253 parts of 3,3′-dichlorobenzidene in dilute HCl and sodium nitrite, is pumped at 26 bar through one of two frontally opposed nozzles, each with a diameter of 300 μm, of a two-jet microjet reactor. Pumped through the second nozzle under the same pressure is an approximately 5% strength aqueous coupling component solution having a temperature of 10° C., prepared by dissolving 354 parts of acetoacetanilide in dilute sodium hydroxide solution, buffered by the addition of 164 parts of sodium acetate. The jets impinge on one another frontally in a gas atmosphere. The resulting pigment suspension is carried off by a stream of compressed air of about 700 l/h, which serves simultaneously to maintain the gas atmosphere at the collision point of the jet. The compressed air stream enters perpendicularly with respect to the two jets, through an opening in the reactor housing. The exit opening for the compressed air and the pigment suspension is situated on the opposite side to the entry opening of the compressed air stream.
[0096] About 900 parts of the resulting pigment suspension are collected, heated to 95° C., and stirred at 95° C. for 30 minutes. After the suspension has cooled to 80° C. it is filtered, the solid product is washed salt-free with water, and the presscake is dried at 95° C. for 15 h and then ground. This gives 44 parts of Pigment Yellow 12.
[0097] The pigment is used to prepare an offset printing ink with a commercially customary heatset offset varnish based on a hard resin in mineral oil. In comparison to a printing ink prepared using a commercially customary Pigment Yellow 12, the printing ink is notable for markedly higher color strength, significantly higher transparency, and higher gloss.
Example 2
[0098] Diazonium salt solution
[0099] 729 parts of 2,5-dichloroaniline are stirred in 2 074.5 parts of water and 2 177.8 parts of aqueous 31% strength hydrochloric acid at room temperature for 8 h. The mixture is cooled to −10° C. by adding 1 500 parts of ice. At this temperature, 770.4 parts of aqueous 40% strength sodium nitrite solution are added rapidly, and the mixture is stirred for 1 h. The diazonium salt solution is clarified by adding 50 g of Tonsil and carrying out filtration with suction. The diazonium salt solution is made up of water to a total volume of 10 liters.
[0100] Solution of the coupling component
[0101] 1 264.5 parts of Naphtol AS are introduced into and dissolved in a mixture of 9 000 parts of water and 1 222.2 parts of aqueous 33% sodium hydroxide solution which is at a temperature of 80° C.
[0102] Azo coupling in the microjet reactor
[0103] The azo coupling takes place in the microjet reactor used in Example 1. The diazonium salt solution, at 27 bar, and the solution of the coupling component, at 31 bar, are sprayed against one another through the two nozzles, with the compressed air stream for carrying off the resulting pigment suspension being approximately 700 l/h.
[0104] The resulting pigment suspension is stirred at 40° C. for about 1 h and then filtered and the solid product is washed salt-free with water. The presscake is dried at 80° C. This gives Pigment Red 2.
[0105] The pigment is used to prepare an offset printing ink with a commercially customary heatset offset varnish based on a hard resin in mineral oil.
[0106] The printing ink is notable for high color strength, transparency, and brightness.
Example 3
[0107] Diazonium salt solution
[0108] 371 parts of 3-amino-4-methoxybenzanilide are stirred in 4 500 parts of water and 808.5 parts of aqueous 31% strength hydrochloric acid for 8 h. Following the addition of 1 000 parts of ice, diazotization is carried out by adding 260.7 parts of aqueous 40% strength sodium nitrite solution. Then 11 parts of a C 16 -C 18 fatty alcohol ethoxylate containing 25 ethylene oxide units and 200 parts of anhydrous sodium acetate are added and the volume is made up with water to 10 liters.
[0109] Solution of the coupling component
[0110] 600 parts of Naphtol AS-LC are introduced into 4 000 parts of water at a temperature of 85° C. and are dissolved together with 502.5 parts of aqueous 33% sodium hydroxide solution. 11 parts of a methyltauride sodium salt based on plant-derived mixed fatty acids are added, the solution is made up with water to a volume of 10 liters, and the temperature is set at 65° C.
[0111] Azo coupling in the microjet reactor
[0112] The azo coupling takes place in the microjet reactor used in Example 1. The diazonium salt solution and the solution of the coupling component are sprayed at 43 to 45 bar through the two nozzles against one another; the compressed air stream for carrying off the resulting pigment suspension is approximately 700 l/h. The temperature of the pigment suspension carried off is from 35 to 40° C. The resulting pigment suspension is stirred at about 40° C. for about 15 minutes and then filtered and the solid product is washed salt-free with water. The presscake is dried at 80° C. This gives Pigment Red 146.
[0113] The pigment is used to prepare a gravure printing ink with a commercially customary nitrocellulose gravure printing varnish based on a collodium wool in ethyl acetate. In comparison to a printing ink prepared with a commercially customary Pigment Red 146, the printing ink features substantially higher transparency and markedly higher gloss.
Example 4
[0114] Diazonium salt suspension
[0115] 287.3 parts of 2-amino-4-chloro-5-methylbenzenesulfonic acid are dissolved in
[0116] 2600 parts of water and 174.2 parts of aqueous 33% strength sodium hydroxide solution at 80° C. and the solution is filtered. After the solution is cooled to 40° C., 465.5 parts of aqueous 31% strength hydrochloric acid are added. The precipitation is stirred overnight at room temperature. Diazotization is carried out by adding
[0117] 227.7 parts of aqueous 40% strength sodium nitrite solution. The volume of the diazonium salt suspension is adjusted to approximately 8 liters with water.
[0118] Solution of the coupling component
[0119] 429 parts of pyrazole acid are dissolved in 2 600 parts of water together with
[0120] 194.2 parts of aqueous 33% strength sodium hydroxide solution. The volume of the coupling component solution is made up to approximately 8 liters with water and warmed to 53° C. by passing steam into it, and then 553.8 parts of 98% disodium hydrogen phosphate are added.
[0121] Azo coupling in the microjet reactor
[0122] The azo coupling takes place in the microjet reactor used in Example 1. The diazonium salt suspension, at about 45 bar, and the solution of the coupling component, at about 34 bar, are sprayed against one another through the two nozzles, the compressed air stream for carrying off the resulting pigment suspension being approximately 1 000 l/h.
[0123] 1 500 parts of the pigment suspension are heated to 80° C., adjusted to a pH of 2 using aqueous 25% strength hydrochloric acid, and stirred for 15 minutes. A solution at a temperature of 80° C., made up of 0.82 part of stearic acid in 10 parts of water and 3 drops of aqueous 33% strength sodium hydroxide solution, and then 30.92 parts of calcium chloride, are added. After stirring at 80° C. for 2 hours the mixture is filtered with suction and the solid product is washed first with aqueous hydrochloric acid with a pH of 2 and then with water. The presscake is dried at 80° C.
[0124] This gives 31.6 parts of Pigment Yellow 191.
[0125] Conventionally prepared Pigment Yellow 191
[0126] The diazoinium salt suspension is prepared in accordance with Example 4a).
[0127] The solution of the coupling component is prepared in accordance with Example 4b) except that no disodium hydrogen phosphate is added.
[0128] Conventional azo coupling is carried out by adding the diazonium salt suspension dropwise to the initial charge of the 40° C. solution of the coupling component. During this addition, the pH is held at 6.3, where appropriate by parallel dropwise addition of a solution of 70.7 parts of disodium hydrogen phosphate in 400 parts of water at 80° C. into the pigment suspension which forms. Following complete addition of the diazonium salt solution, the reaction mixture is heated to 800° C. and adjusted to a pH of 2.0 using aqueous 25% strength hydrochloric acid, and then a solution of 1.1 parts of stearic acid in water and a few drops of aqueous 33% strength sodium hyrdoxide solution, and, finally, 33.3 parts of calcium chloride, are added. After stirring at 80° C. for 2 hours the reaction mixture is filtered with suction and the solid product is washed first with aqueous hydrochloric acid, with a pH of 2, and then with water. The presscake is dried at 80° C.
[0129] This gives 41 parts of Pigment Yellow 191.
[0130] Testing in plasticized PVC
[0131] In a commercially customary plasticized PVC test system, a transparent PVC film is produced with each of the pigments prepared in accordance with Example 4c and Example 4d. The pigment prepared inventively in accordance with Example 4c gives a strongly colored, transparent, bright, and pure PVC coloration. The pigment prepared conventionally in accordance with Example 4d cannot be dispersed satisfactorily, and the PVC film exhibits distinct specks and is weaker in color.
Example 5
[0132] An approximately 3% strength aqueous 3,3′-dichlorobenzidene tetraazo solution with a temperature of 10° C., prepared by bisdiazotizing 253 parts of 3,3′-dichlorobenzidene in dilute HCI and sodium nitrite, is pumped at 25 bar through one nozzle of the microjet reactor used in Example 1. Pumped through the second nozzle under the same pressure is an approximately 3% strength aqueous coupling component solution having a temperature of 20° C., prepared by dissolving 354 parts of acetoacetanilide in dilute sodium hydroxide solution, buffered by the addition of 164 parts of sodium acetate. The compressed air stream is approximately 700 l/h.
[0133] About 900 parts of the resulting pigment suspension are collected, heated to 95° C., and stirred at 95° C. for 2 h. After the suspension has cooled to 80° C. it is filtered, the solid product is washed salt-free with water, and the presscake is dried at 95° C. for 15 h and then ground. This gives 26 parts of Pigment Yellow 12.
[0134] The pigment is used to prepare an offset printing ink with a commercially customary heatset offset varnish based on a hard resin in mineral oil. In comparison to a printing ink prepared using a commercially customary Pigment Yellow 12, the printing ink is notable for markedly higher color strength, significantly higher transparency, and higher gloss. The particle size distribution, determined by electron microscopy, shows an average for the pigment prepared using the microjet reactor that is about 30% lower than that of the commercially customary P.Y. 12. | The invention provides a process for preparing azo colorants which comprises spraying one or more coupling components individually or in a mixture and one or more compatible diazonium salts individually or in a mixture, in their solution or suspension form through nozzles to a point of conjoint collision in a reactor chamber enclosed by a housing in a microjet reactor, a gas or an evaporating liquid being passed into the reactor chamber through an opening in the housing for the purpose of maintaining a gas atmosphere in the reactor chamber, and the resulting product solution or suspension and the gas or the evaporated liquid being removed from the reactor through a further opening in the housing by means of overpressure on the gas entry side or underpressure on the product and gas exit side. | 2 |
SUMMARY
This device is designed to provide people who hang doors with an adjustable tool for establishing the pattern of a door frame, which is then transferred to the door, allowing the door to be planed to a precise fit before the door is hung. It is an objective of this invention to minimize or eliminate wasteful time needed to fit a door to a door frame by trial and error methods, and to eliminate the construction of temporary one-time useable door frame patterns. The reuseable, adjustable door frame pattern which quickly and easily adjusts to a wide variety of door frame sizes reduces the time and labor of hanging doors, thus increasing the efficiency of the personnel with a resultant savings in cost. A further objective of the invention is to provide a safe, economical tool which is within the means of a small business, even an individual, contracting to hang doors.
DESCRIPTION OF THE PRIOR ART
1. Field of the Invention.
This invention relates to construction industry hand tools, and more specifically to door frame patterns.
2. Description of the Prior Art.
It is very common among door hangers to measure door frames, apply the measurements to a door, then preform preliminary planing. Usually the door is then placed in the frame, and additional planing requirements established, and preformed before a final fit is achieved. Depending upon the expertise of the door hanger, several measuring and planing operations may be required to obtain a satisfactory fit. It is not uncommon for a door hanger to build out of wood, a pattern of the door frame which can be used to transfer the door frame pattern onto the door. However the use of such makeshift pattern lack precision, are one-time useable, and take substantial time to make.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of the invention.
FIG. 2 is an enlarged isometric exploded view of an area generally indicated by the letter B in FIG. 1.
FIG. 3 is a plan view of the top of the invention in a top of a door frame.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIG. 1 the invention has an adjustable frame 1, a plurality of top screw rods 3, and a plurality of bottom screw rods 4, and a pressure plate 18. The frame 1 is made of rigid material, and has two side beams 5 and a plurality of cross beams 6. Angle metal has been found to be very satisfactory for the frame 1 and the pressure plate 18. When using angle metal, one flange of the metal, such as aluminum, in the side beams 5 and cross beams 6 should be in one plane which will be a smooth side to be placed on a door without scratching the door. The angle metal used in the pressure plate 18 should be oriented so that a flange of the metal is parallel to, but in a different plane than the smooth side so that a definite edge is to be bearing on the door. It has been found that five cross beams 6 are sufficient for most uses; however more or less may be employed as required by size. Each cross beam 6 consists of two slotted arms 7, each slotted arm 7 being rigidly affixed at right angles to one of the side beams 5 in a smooth non-scratching manner such as by flush riveting. The slotted arms 7 have longitudinal slots 8 sized to accept a carriage bolt 9. One or more bolts 9 may pass through the slots 8 in each cross beam 6 and opposing slotted arms 7, from the smooth side to the interior of the right angle of the angle metal are secured to each other by a nut 10 on the bolt 9. The nuts 10 are shown as wing nuts, however any standard nut may be used. Thus the frame 1 is adjustable in width by loosening the nuts 10 on all cross beams 6, setting the width of the side beams 5 and tightening the nuts 10; and the smooth heads of the carriage bolts 9 are on the smooth side of the frame 1. It should be pointed out that the slotted arms 7 may be angle or channel metal to insure that the squareness of the frame 1 is retained; however tubing allowing one slotted arm 7 to slide into and out of the opposing slotted arm 7, or extension beam 11, as well as any other similar design, may be used. In addition, to increase the adjustability of the frame 1, extension beams 11 slotted similar to the slotted arms 7 may be used to connect opposing slotted arms 7, as shown in FIG. 1. The extension beams 11 are affixed to the slotted arms 7 by carriage bolts 9 and nuts 10 in a manner similar to the aforementioned method of affixing opposing slotted arms 7. One of the side beams 5, designated clearance rail 15 has on its edge a plurality of clearance means 12. The clearance means 12 are shown as simple bolts 13 and washers 14 rigidly affixed to the outside of the clearance rail 15 to provide approximately three-sixteenths of an inch clearance along a vertical side of the door frame. This clearance provides the standard three-thirty seconds of an inch, as required by architects, on each side of the door. It is obvious however than an adjustable clearance means 12 such as a screw threaded through the clearance rail 15 may be employed to provide a means for adjusting the clearance for specialized useage. The clearance means 12 are disposed adjacent to the ends of the clearance rail 15. There are four clearance means 12 shown, two disposed toward the top and two disposed toward the bottom. By providing two clearance means 12 at each end, the possibility of a single clearance means 12 at either end falling into a pre-cut hinge mounting notch is avoided.
The other side beam 5 is designated the spring rail 16. The spring rail 16 has a plurality of equally spaced blocks 30 in the angle of the angle metal and bolt holes 17 through the spring rail 16 and the blocks 30. The pressure plate 18 being a rigid longitudinal member of angle metal approximately the same length as a side beam 5, but preferrably slightly longer, has in one flange which is parallel to the smooth side of the frame, a plurality of spring bolts holes 25, each of which has inserted therein a loose bushing 26. As shown in FIG. 2, through the flange of the angle metal of the pressure plate 18 and through the diameter of the spring bolt holes 25 are flex-cuts 24. There are no flex-cuts in the flange through the two spring bolt holes 25 which are nearest the ends of the pressure plate 18. The spring bolts 19 have eyes on one end and are threaded on the other end. An attaching bolt 27 passes from the angle side of the pressure plate 18 through the eye in the spring bolt 19, then through the spring bolt holes 25, the loose bushing 26 therein, and is secured therein by the attaching nut 28, so that the attaching nut 28 is away from the smooth side of the frame 1. The number of spring bolts 19 is the same as the number of bolt holes 17 and the spring bolts 19 are coorespondingly spaced so that the spring bolts 19 slide into the bolt holes 17. Over each of the spring bolts 19 is a helical spring 20, and when the spring bolts 19 are inserted into the bolt holes 17, the helical springs 20 bear against the pressure plate 18 and the spring rail 16 biasing the pressure plate 18 away from the spring rail 16. The pressure plate 18 is secured to the spring rail 16 by spring nuts 21 on each spring bolt 19. It is to be noted that the pressure plate 18, by virtue of the flex-cuts 24 is to a degree, flexible and will conform to door frames which are slightly other than straight.
Between the side beams 5 on one end are two top screw rods 3. The top screw rods 3 are long threaded screws, turnable by hand or ratchet. The two screw rods 3 are threaded through matingly threaded screw blocks 22 mounted on the slotted arms 7. Each top screw rod 3 should be adjacent to a side beam 5. Also between the side beams 5 on the other end of the invention are two bottom screw rods 4 identical to the top screw rods 3, and likewise mounted in screw blocks 22, adjacent to the other ends of the side beams 5.
Thus assembled, the invention is adjusted so that it is slightly wider than the door frame in which the door is to be hung, and the top screw rods 3 and the bottom screw rods 4 are screwed so that the overall length of the invention is slightly shorter than the height of the door frame. The invention is then placed in the door frame as illustrated in FIG. 3, with the pressure plate 18 being forced toward the spring rail 16 by one side of the door frame, and the clearance means 12 bearing against the other side of the door frame. The spring nuts 21 are then tightened finger tight. The top screw rods 3 are then screwed up until just touching the top of the door frame, and the bottom screw rods 4 are screwed down until just touching the floor. The invention is then removed from the door frame, and placed, smooth side next to a door, on the door. The clearance means 12 has lips 23, which are shown as a protruding part of the washers. The lips 23 protrude generally perpendicular to the overall plane of the invention, along the edge of the clearance rail 15. Thus the invention is placed on the door with a vertical edge of the door against the lips 23, and the other edge of the door scribed along the edge of the pressure plate 18. Marks are made at the protruding end of the top screw rods 3 and the bottom screw rods 4. Using any commonly available straight edge, the door is scribed through the marks. Thus scribed, the door can be easily planed top, bottom, and one edge for a precise fit with predetermined clearance. In addition the invention is easily adjustable for use in another door frame. A standard size door frame pattern can easily be adjusted for doors from two feet wide to four feet wide, and from six feet high to eight feet high. However, in general there should be a standard size frame, and outsized frames built as required for a job, since the majority of door sizes handled by professional door hangars are within a narrower size range. | A device which can be placed in a door frame, set and adjusted to the precise dimensions of the door frame; then removed and placed on the door, providing a means for indicating the amount and location of planing to be done to a door to insure a precise fit when the door is hung. | 8 |
APPLICATION DATA
[0001] This application is a divisional application of U.S. application Ser. No. 11/284,836 filed Nov. 22, 2005 which claims priority to German application DE 10 2004 058 337 filed Dec. 2, 2004, both of which are incorporated herein in their entirety by reference.
[0002] The invention relates to a process for preparing fused piperazin-2-one derivatives of general formula (I)
wherein the groups R 1 to R 5 have the meanings given in the claims and specification, particularly a process for preparing 7,8-dihydro-5H-pteridin-6-one derivatives.
BACKGROUND TO THE INVENTION
[0003] Pteridinone derivatives are known from the prior art as active substances with an antiproliferative activity. WO 03/020722 describes the use of dihydropteridinone derivatives for the treatment of tumoral diseases and processes for preparing them.
[0004] 7,8-Dihydro-5H-pteridin-6-one derivatives of formula (I) are important intermediate products in the synthesis of these active substances. Up till now they have been prepared using methods involving reduction of nitro compounds of formula (II) below, which led to strongly coloured product mixtures and required laborious working up and purification processes.
[0005] WO 96/36597 describes the catalytic hydrogenation of nitro compounds using noble metal catalysts with the addition of a vanadium compound, while disclosing as end products free amines, but no lactams.
[0006] The aim of the present invention is to provide an improved process for preparing compounds of formula (I), particularly 7,8-dihydro-5H-pteridin-6-one derivatives.
DETAILED DESCRIPTION OF THE INVENTION
[0007] The present invention solves the problem outlined above by the method of synthesising compounds of formula (I) described hereinafter.
[0008] The invention thus relates to a process for preparing compounds of general formula I
wherein
R 1 denotes a group selected from the group consisting of chlorine, fluorine, bromine, methanesulphonyl, ethanesulphonyl, trifluoromethanesulphonyl, para-toluenesulphonyl, CH 3 S(═O)— and phenylS(═O)— R 2 denotes hydrogen or C 1 -C 3 -alkyl, R 3 denotes hydrogen or a group selected from the group consisting of optionally substituted C 1 -C 12 -alkyl, C 2 -C 12 -alkenyl, C 2 -C 12 -alkynyl and C 6 -C 14 -aryl, or a group selected from the group consisting of optionally substituted and/or bridged C 3 -C 12 -cycloalkyl, C 3 -C 12 -cycloalkenyl, C 7 -C 12 -polycycloalkyl, C 7 -C 12 -polycycloalkenyl, C 5 -C 12 -spirocycloalkyl and saturated or unsaturated C 3 -C 12 -heterocycloalkyl, which contains 1 to 2 heteroatoms, R 4 , R 5 which may be identical or different denote hydrogen or optionally substituted C 1 -C 6 -alkyl, or R 4 and R 5 together denote a 2- to 5-membered alkyl bridge which may contain 1 to 2 heteroatoms, or R 4 and R 3 or R 5 and R 3 together denote a saturated or unsaturated C 3 -C 4 -alkyl bridge, which may optionally contain 1 heteroatom, and A 1 and A 2 which may be identical or different represent —CH═ or —N═, preferably —N═, in which a compound of formula II
wherein
R 1 -R 5 and A 1 , A 2 have the stated meaning and R 6 denotes C 1 -C 4 -alkyl, a) is hydrogenated with hydrogen in the presence of a hydrogenation catalyst and b) a copper, iron or vanadium compound is added,
in which steps a) and b) may take place simultaneously or successively.
[0020] In a preferred process, the hydrogenation of the compound of formula II is carried out directly in the presence of the hydrogenation catalyst and the copper, iron or vanadium compound to form the compound of formula I.
[0021] In a particularly preferred process, after the first hydrogenation step a), first of all the intermediate product of formula III is obtained, which may optionally be isolated,
and is then further reduced in the presence of a hydrogenation catalyst and a copper, iron or vanadium compound to form a compound of formula I
[0022] Also preferred is a process in which the hydrogenation catalyst is selected from the group consisting of rhodium, ruthenium, iridium, platinum, palladium and nickel, preferably platinum, palladium and Raney nickel. Platinum is particularly preferred. Platinum may be used in metallic form or oxidised form as platinum oxide on carriers such as e.g. activated charcoal, silicon dioxide, aluminium oxide, calcium carbonate, calcium phosphate, calcium sulphate, barium sulphate, titanium dioxide, magnesium oxide, iron oxide, lead oxide, lead sulphate or lead carbonate and optionally additionally doped with sulphur or lead. The preferred carrier material is activated charcoal, silicon dioxide or aluminium oxide.
[0023] Preferred copper compounds are compounds in which copper assumes oxidation states I or II, for example the halides of copper such as e.g. CuCl, CuCl 2 , CuBr, CuBr 2 , CuI or CuSO 4 . Preferred iron compounds are compounds wherein iron assumes oxidation states II or III, for example the halides of iron such as e.g. FeCl 2 , FeCl 3 , FeBr 2 , FeBr 3 , FeF 2 or other iron compounds such as e.g. FeSO 4 , FePO 4 or Fe(acac) 2 .
[0024] Preferred vanadium compounds are compounds wherein vanadium assumes the oxidation states 0, II, III, IV or V, for example inorganic or organic compounds or complexes such as e.g. V 2 O 3 , V 2 O 5 , V 2 O 4 , Na 4 VO 4 , NaVO 3 , NH 4 VO 3 , VOCl 2 , VOCl 3 , VOSO 4 , VCl 2 , VCl 3 , vanadium oxobis(1-phenyl-1,3-butanedionate), vanadium oxotriisopropoxide, vanadium(III) acetylacetonate [V(acac) 3 ] or vanadium(IV) oxyacetylacetonate [VO(acac) 2 ]. Vanadium(IV) oxyacetylacetonate [VO(acac) 2 ] is particularly preferred
[0025] The copper, iron or vanadium compound may be used either directly at the start of the hydrogenation or after the formation of the intermediate of formula (III), as preferred.
[0026] Also preferred is a process wherein the amount of added hydrogenation catalyst is between 0.1 and 10 wt.-% based on the compound of formula (II) used.
[0027] Also preferred is a process wherein the amount of copper, iron or vanadium compound used is between 0.01 and 10 wt.-% based on the compound of formula (II) used.
[0028] Also preferred is a process wherein the reaction is carried out in a solvent selected from the group consisting of dipolar, aprotic solvents, for example dimethylformamide, dimethylacetamide, N-methylpyrrolidinone, dimethylsulphoxide or sulpholane; alcohols, for example methanol, ethanol, 1-propanol, 2-propanol, the various isomeric alcohols of butane and pentane; ethers, for example diethyl ether, methyl-tert.-butylether, tetrahydrofuran, 2-methyltetrahydrofuran, dioxane or dimethoxyethane; esters, for example ethyl acetate, 2-propylacetate or 1-butylacetate; ketones, for example acetone, methylethylketone or methylisobutylketone; carboxylic acids, for example acetic acid; apolar solvents, for example toluene, xylene, cyclohexane or methylcyclohexane, as well as acetonitrile, methylene chloride and water. The solvents may also be used as mixtures.
[0029] Also preferred is a process wherein the reaction temperature is between 0° C. and 150° C., preferably between 20° C. and 100° C.
[0030] Also preferred is a process wherein the hydrogen pressure is 1 bar to 100 bar.
[0031] The invention further relates to a compound of formula (III)
wherein R 1 to R 5 may have the stated meaning.
[0032] Preferred compounds of formula (III) are those wherein A 1 and A 2 are identical and denote —N═.
[0033] The reactions are worked up by conventional methods e.g. by extractive purification steps or precipitation and crystallisation methods.
[0034] The compounds according to the invention may be present in the form of the individual optical isomers, mixtures of the individual enantiomers, diastereomers or racemates, in the form of the tautomers as well as in the form of the free bases or the corresponding acid addition salts with acids—such as for example acid addition salts with hydrohalic acids, for example hydrochloric or hydrobromic acid, or organic acids, such as for example oxalic, fumaric, diglycolic or methanesulphonic acid.
[0035] Examples of alkyl groups, including those which are part of other groups, are branched and unbranched alkyl groups with 1 to 12 carbon atoms, preferably 1-6, particularly preferably 1-4 carbon atoms, such as for example: methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl and dodecyl. Unless otherwise stated, the above-mentioned designations propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl and dodecyl include all the possible isomeric forms. For example the term propyl includes the two isomeric groups n-propyl and iso-propyl, the term butyl includes n-butyl, iso-butyl, sec. butyl and tert.-butyl, the term pentyl includes isopentyl, neopentyl etc.
[0036] In the above-mentioned alkyl groups one or more hydrogen atoms may optionally be replaced by other groups. For example these alkyl groups may be substituted by fluorine. It is also possible for all the hydrogen atoms of the alkyl group to be replaced.
[0037] Examples of alkyl bridges, unless otherwise stated, are branched and unbranched alkyl groups with 2 to 5 carbon atoms, for example ethylene, propylene, isopropylene, n-butylene, iso-butyl, sec. butyl and tert.-butyl etc. bridges. Particularly preferred are ethylene, propylene and butylene bridges. In the above-mentioned alkyl bridges 1 to 2 C atoms may optionally be replaced by one or more heteroatoms selected from among oxygen, nitrogen or sulphur.
[0038] Examples of alkenyl groups (including those which are part of other groups) are branched and unbranched alkylene groups with 2 to 12 carbon atoms, preferably 2-6 carbon atoms, particularly preferably 2-3 carbon atoms, provided that they have at least one double bond. The following are mentioned by way of example: ethenyl, propenyl, butenyl, pentenyl etc. Unless otherwise stated, the above-mentioned designations propenyl, butenyl etc. include all the possible isomeric forms. For example the term butenyl includes 1-butenyl, 2-butenyl, 3-butenyl, 1-methyl-1-propenyl, 1-methyl-2-propenyl, 2-methyl-1-propenyl, 2-methyl-2-propenyl and 1-ethyl-1-ethenyl.
[0039] In the above-mentioned alkenyl groups, unless otherwise described, one or more hydrogen atoms may optionally be replaced by other groups. For example these alkyl groups may be substituted by the halogen atom fluorine. It is also possible for all the hydrogen atoms of the alkenyl group to be replaced.
[0040] Examples of alkynyl groups (including those which are part of other groups) are branched and unbranched alkynyl groups with 2 to 12 carbon atoms, provided that they have at least one triple bond, for example ethynyl, propargyl, butynyl, pentynyl, hexynyl etc., preferably ethynyl or propynyl.
[0041] In the above-mentioned alkynyl groups, unless otherwise described, one or more hydrogen atoms may optionally be replaced by other groups. For example these alkyl groups may be fluorosubstituted. It is also possible for all the hydrogen atoms of the alkynyl group to be replaced.
[0042] The term aryl denotes an aromatic ring system with 6 to 14 carbon atoms, preferably 6 or 10 carbon atoms, preferably phenyl, which, unless otherwise described, may for example carry one or more of the following substituents: OH, NO 2 , CN, OMe, —OCHF 2 , —OCF 3 , halogen, preferably fluorine or chlorine, C 1 -C 10 -alkyl, preferably C 1 -C 5 -alkyl, preferably C 1 -C 3 -alkyl, particularly preferably methyl or ethyl, —O—C 1 -C 3 -alkyl, preferably —O-methyl or —O-ethyl, —COOH, —COO—C 1 -C 4 -alkyl, preferably —O-methyl or —O-ethyl, —CONH 2 .
[0043] Examples of cycloalkyl groups are cycloalkyl groups with 3-12 carbon atoms, for example cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl or cyclooctyl, preferably cyclopropyl, cyclopentyl or cyclohexyl, while each of the above-mentioned cycloalkyl groups may optionally also carry one or more substituents, for example: OH, NO 2 , CN, OMe, —OCHF 2 , —OCF 3 or halogen, preferably fluorine or chlorine, C 1 -C 10 -alkyl, preferably C 1 -C 5 -alkyl, preferably C 1 -C 3 -alkyl, particularly preferably methyl or ethyl, —O—C 1 -C 3 -alkyl, preferably —O-methyl or —O-ethyl, —COOH, —COO—C 1 -C 4 -alkyl, preferably —COO-methyl or —COO-ethyl or —CONH 2 . Particularly preferred substituents of the cycloalkyl groups are ═O, OH, methyl or F.
[0044] Examples of cycloalkenyl groups are cycloalkyl groups with 3-12 carbon atoms, which have at least one double bond, for example cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl or cycloheptenyl, preferably cyclopropenyl, cyclopentenyl or cyclohexenyl, while each of the above-mentioned cycloalkenyl groups may optionally also carry one or more substituents.
[0045] “═O” denotes an oxygen atom linked by a double bond.
[0046] Examples of heterocycloalkyl groups are, unless otherwise described in the definitions, 3- to 12-membered, preferably 5-, 6- or 7-membered, saturated or unsaturated heterocycles, which may contain nitrogen, oxygen or sulphur as heteroatoms, for example tetrahydrofuran, tetrahydrofuranone, γ-butyrolactone, α-pyran, γ-pyran, dioxolane, tetrahydropyran, dioxane, dihydrothiophene, thiolane, dithiolane, pyrroline, pyrrolidine, pyrazoline, pyrazolidine, imidazoline, imidazolidine, tetrazole, piperidine, pyridazine, pyrimidine, pyrazine, piperazine, triazine, tetrazine, morpholine, thiomorpholine, diazepan, oxazine, tetrahydro-oxazinyl, isothiazole and pyrazolidine, preferably morpholine, pyrrolidine, piperidine or piperazine, while the heterocycle may optionally carry substituents, for example C 1 -C 4 -alkyl, preferably methyl, ethyl or propyl.
[0047] Examples of polycycloalkyl groups are optionally substituted, bi-, tri-, tetra- or pentacyclic cycloalkyl groups, for example pinane, 2,2,2-octane, 2,2,1-heptane or adamantane. Examples of polycycloalkenyl groups are optionally bridged and/or substituted, 8-membered bi-, tri-, tetra- or pentacyclic cycloalkenyl groups, preferably bicycloalkenyl or tricycloalkenyl groups, if they contain at least one double bond, for example norbornene.
[0048] Examples of spiroalkyl groups are optionally substituted spirocyclic C 5 -C 12 alkyl groups.
[0049] Halogen generally denotes fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine, particularly preferably chlorine.
[0050] The substituent R 1 may represent a group selected from the group consisting of chlorine, fluorine, bromine, methanesulphonyl, ethanesulphonyl, trifluoromethanesulphonyl and para-toluenesulphonyl, preferably chlorine.
[0051] The substituent R 2 may represent hydrogen or C 1 -C 3 -alkyl, preferably hydrogen.
[0052] The substituent R 3 may represent hydrogen,
or a group selected from the group consisting of optionally substituted C 1 -C 12 -alkyl, C 2 -C 12 -alkenyl, C 2 -C 12 -alkynyl, and C 6 -C 14 -aryl, preferably phenyl, or a group selected from the group consisting of optionally substituted and/or bridged C 3 -C 12 -cycloalkyl, preferably cyclopentyl, C 3 -C 12 -cycloalkenyl, C 7 -C 12 -polycycloalkyl, C 7 -C 12 -polycycloalkenyl, C 5 -C 12 -spirocycloalkyl and saturated or unsaturated C 3 -C 12 -heterocycloalkyl, which contains 1 to 2 heteroatoms.
[0054] The substituents R 4 , R 5 may be identical or different and may represent hydrogen,
or optionally substituted C 1 -C 6 -alkyl, or R 4 and R 5 together represent a 2- to 5-membered alkyl bridge which may contain 1 to 2 heteroatoms, or R 4 and R 3 or R 5 and R 3 together represent a saturated or unsaturated C 3 -C 4 -alkyl bridge, which may optionally contain 1 heteroatom.
[0058] A 1 and A 2 which may be identical or different represent —CH═ or —N═, preferably —N═.
[0059] R 6 may represent a C 1 -C 4 -alkyl, preferably methyl or ethyl.
[0060] The compound of formula (II) may be prepared according to methods known from the literature, for example analogously to the syntheses described in WO 03/020722.
[0061] The compounds of general formula (I) may be prepared inter alia analogously to the following examples of synthesis. These Examples are, however, intended only as examples of procedures to illustrate the invention, without restricting it to their content. The general synthesis is shown in Scheme (1).
Synthesis of (7R)-2-chloro-8-cyclopentyl-7-ethyl-5-hydroxy-7,8-dihydro-5H-pteridin-6-one
[0062]
[0063] 30 g (84.2 mmol) of 1 are dissolved in 300 ml of tetrahydrofuran and 3 g Pt/C (5%) are added. The reaction mixture is hydrogenated for 5 h at 35° C. and a hydrogen pressure of 4 bar. The catalyst is filtered off and washed with approx. 30 ml of tetrahydrofuran. The filtrate is concentrated by evaporation under reduced pressure. 25.6 g of product 2 are obtained as a yellow solid.
[0064] 1 H-NMR (400 MHZ) (DMSO d6 ): δ 11.05 (bs 1H); 7.85 (s 1H); 4.47-4.45 (dd 1H); 4.16-4.08 (t 1H); 1.95-1.67 (m 10H); 0.80-0.73 (t 3H)
Synthesis of (7R)-2-chloro-8-cyclopentyl-7-ethyl-7,8-dihydro-5H-pteridin-6-one
[0065]
[0066] 5.22 g (17.6 mmol) of 2 are dissolved in 55 ml of tetrahydrofuran. 520 mg Pt—C (5%) and 250 mg vanadium(IV) oxyacetylacetonate are added. The reaction mixture is hydrogenated for 6 hours at 20° C. and a hydrogen pressure of 4 bar. The catalyst is filtered off and washed with approx. 15 ml of tetrahydrofuran. The filtrate is concentrated by evaporation under reduced pressure.
[0067] 5.0 g of product 3 are obtained as a yellow powder.
[0068] 1 H-NMR (400 MHz) (DMSO d6 ): δ 11.82 (bs 1H); 7.57 (s 1H); 4.24-4.21 (dd 1H); 4.17-4.08 (m 1H); 1.97-1.48 (m 10H); 0.80-0.77 (t 3H).
Synthesis of: (7R)-2-chloro-8-cyclopentyl-7-ethyl-7,8-dihydro-5H-pteridin-6-one
[0069] 70 g Pt/C (5%) are added to a solution of 700 g (1.96 mol) of 1 in 700 ml of tetrahydrofuran. The reaction mixture is hydrogenated for 2.5 hours at 35° C. and a hydrogen pressure of 4 bar until the hydrogen uptake has stopped. The autoclave is opened and 35 g vanadium(IV) oxyacetylacetonate are added. The mixture is hydrogenated for a further 2.5 hours at 35° C. and a hydrogen pressure of 4 bar. It is filtered and the residue is washed with tetrahydrofuran. The filtrate is concentrated by evaporation under reduced pressure. The residue is dissolved in 2.75 L acetone and precipitated by the addition of an equal amount of demineralised water. The solid is suction filtered and washed with an acetone/water mixture (1:1), then with tert.-butylmethylether. After drying 551 g of product 3 are obtained.
Synthesis of: (7R)-2-chloro-8-cyclopentyl-7-ethyl-7,8-dihydro-5H-pteridin-6-one
[0070] 30 g (84 mmol) of 1 are dissolved in 300 ml of tetrahydrofuran. 3 g Pt/C (5%) and 1.5 g vanadium(IV) oxyacetylacetonate are added. The reaction mixture is hydrogenated for 24 hours at 35° C. and a hydrogen pressure of 4 bar until the reaction is complete. It is filtered, the residue is washed with tetrahydrofuran and the filtrate is concentrated by evaporation under reduced pressure. The residue is dissolved in 118 ml acetone and precipitated by the addition of an equal amount of demineralised water. The solid is suction filtered and washed with an acetone/water mixture (1:1) and then with tert.-butylmethylether. After drying 18 g of product 3 are obtained.
Synthesis of: (7R)-2-chloro-7-ethyl-8-isopropyl-7,8-dihydro-5H-pteridin-6-one
[0071]
[0072] 10 g (316 mmol) of 4 are dissolved in 800 ml of tetrahydrofuran and 200 ml isopropanol. 10 g Pt/C (5%) and 5 g vanadium(IV) oxyacetylacetonate are added. The reaction mixture is hydrogenated for 24 hours at 35° C. and a hydrogen pressure of 4 bar until the reaction is complete. It is filtered and the filtrate is evaporated down until crystallisation sets in. 150 ml isopropanol are added and the suspension is heated to 70-80° C. until fully dissolved. After the addition of 600 ml demineralised water the product is brought to crystallisation. It is suction filtered and washed with demineralised water. After drying 68 g of product 5 are obtained.
[0073] 1 H-NMR (400 MHz) (DMSO d6 ): δ 10.81 (bs 1H); 7.56 (s 1H); 4.37-4.24 (m 2H); 1.89-1.65 (m 2H); 1.34-1.31 (m 6H); 0.80-0.73 (t 3H) | Disclosed are processes for the preparation of fused piperazin-2-one derivatives of general formula (I)
wherein the groups R 1 to R 5 , A 1 and A 2 have the meanings given in the claims and in the description, particularly the preparation of 7,8-dihydro-5H-pteridin-6-one derivatives and intermediates thereof. | 2 |
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