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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. Provisional Patent Application No. 62/068,516 filed on Oct. 24, 2014, which is hereby incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present invention relates generally to the field of position sensors, and more particularly to a fully integrated position sensor assembly.
BACKGROUND ART
[0003] Position sensors are used in many applications, including aircraft, military, transportation, energy, automation and industrial. Such sensors may include encoders, hall position sensors, potentiometers, resolvers and rotary variable differential transformers (RVDTs). RVDTs and resolvers are used in critical applications where more reliable solutions are required. For example, in the aircraft market, the use of fly-by-wire and fly-by-light architectures means that more position sensors are required on each airframe. RVDTs are well known in the market. An electromechanical transducer is used to provide a variable alternating current output voltage that is generally linearly proportional to the angular displacement of an input shaft.
DISCLOSURE OF THE INVENTION
[0004] With parenthetic reference to the corresponding parts, portions, or surfaces of the disclosed embodiment, merely for purposes of illustration and not by way of limitation, provided is a position sensor assembly ( 15 ) comprising a housing ( 16 ) having a least one inner cavity ( 20 , 21 ), a stator ( 22 ) disposed within the housing, a moving element ( 23 ) disposed within the housing and configured and arranged to move relative to the stator, the stator comprising primary windings ( 24 ) and secondary windings ( 25 , 26 ), the secondary windings configured and arranged to provide an output signal ( 27 ) as a function of movement of the moving element relative to the stator, signal conditioning electronics ( 28 ) disposed in the housing and communicating with the primary windings and the secondary windings, the signal conditioning electronics comprising an integrated circuit ( 29 ) configured and arranged to provide excitation of the primary windings and to demodulate the output signal of the secondary windings, and an input element ( 35 ) extending through the housing and connected to the moving element.
[0005] The housing may comprise a sensor housing subassembly ( 18 ) having a first inner cavity ( 20 ) and an electronics housing subassembly ( 19 ) having a second inner cavity ( 21 ), and the stator and the moving element may be disposed within the first inner cavity of the sensor housing subassembly, and the signal conditioning electronics may be disposed within the second inner cavity of the electronics housing subassembly. The electronics housing subassembly may be removably connected to the sensor housing subassembly. The sensor housing subassembly may comprise a bearing end portion ( 36 ), a sensor body portion ( 38 ) and an intermediate portion ( 39 ), and the electronics housing subassembly may comprise an electronics body portion ( 40 ) and a second end portion ( 41 ). The sensor housing subassembly may comprise a signal output port. The moving element may be configured and arranged to move linearly along a central axis relative to the stator or to rotate about a central axis relative to the stator. The moving element may comprise a magnet. The stator and moving element may be selected from a group consisting of a rotary variable differential transformer and a resolver. The signal conditioning electronics may comprise a converter configured and arranged to convert the output signal to a digital signal. The signal conditioning electronics may comprise a signal filter configured and arranged to filter out a carrier frequency. The signal conditioning electronics may comprise a DC signal buffer. The assembly may comprise a temperature sensor ( 55 ) configured and arranged to provide a temperature signal ( 101 ) to the integrated circuit and the integrated circuit is configured and arranged to provide mover position output ( 104 ) compensated ( 84 ) as a function of the temperature signal. The assembly may comprise a mover positional calibration data ( 127 ) and the integrated circuit is configured and arranged to provide a mover position output ( 94 ) compensated ( 83 ) as a function of the calibration data. The assembly may comprise a temperature sensor ( 55 ) configured and arranged to provide a temperature signal ( 101 ) to the integrated circuit and a mover positional calibration data ( 117 , 127 ), and the integrated circuit is configured and arranged to provide a mover position output ( 85 ) compensated as a function of the calibration data and the temperature signal.
[0006] In another aspect, a method of calibrating a position sensor assembly ( 15 ) is provided comprising the steps of providing a position sensor assembly having a housing with at least one inner cavity, a stator disposed within the housing, a moving element disposed within the housing and configured and arranged to move relative to the stator, an input element extending through the housing and connected to the moving element, the stator comprising primary windings and secondary windings, the secondary windings configured and arranged to provide an output signal as a function of movement of the moving element relative to the stator. The calibration method further comprises providing signal conditioning electronics in the housing having a memory and an integrated circuit communicating with the primary windings and the secondary windings and configured and arranged to provide excitation of the primary winding and to condition the output signal of the secondary windings, providing a temperature sensor in said housing, mounting the position sensor assembly on an external actuator ( 111 , 121 ), wherein the external actuator is configured and arranged to drive the moving element of the position sensor assembly through a range of reference positions, operating the external actuator through the range of reference positions, calculating a position error ( 115 ) as a function of the output signal of the secondary windings ( 113 ) and the reference position ( 112 ), sensing a measured temperature ( 124 ) with the temperature sensor of the position sensor assembly, calculating a temperature error ( 125 ) as a function of the output signal of the secondary windings ( 123 ), the measured temperature ( 124 ), and a temperature reference ( 122 ), and storing the position error ( 116 ) and the temperature error ( 126 ) in the memory ( 59 ). The method may further comprise the step of providing a mover position output ( 85 ) compensated as a function of the position error ( 117 ) and the temperature error ( 127 ).
[0007] In another aspect, a method of compensating a position sensor assembly is provided comprising the steps of providing a position sensor assembly having a housing with at least one inner cavity, a stator disposed within said housing, a moving element disposed within the housing and configured and arranged to move relative to the stator, an input element extending through the housing and connected to the moving element, the stator comprising primary windings and secondary windings, the secondary windings configured and arranged to provide an output signal as a function of movement of the moving element relative to the stator; providing signal conditioning electronics in the housing having a memory and an integrated circuit communicating with the primary windings and said secondary windings and configured and arranged to provide excitation of the primary winding and to condition the output signal of the secondary windings, providing a positional calibration dataset ( 117 ), providing a temperature calibration dataset ( 127 ), providing a temperature sensor in the housing; connecting the moving element to an external actuator; operating the external actuator; taking temperature measurements with the temperature sensor, and providing a mover position output ( 85 ) compensated as a function of the output signal of the secondary windings ( 81 ), the temperature measurements ( 101 ), the positional calibration dataset and the temperature calibration dataset.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of a first embodiment of an improved position sensor assembly.
[0009] FIG. 2 is a cross-sectional view of the position sensor assembly shown in FIG. 1 .
[0010] FIG. 3 is an exploded view of the position sensor assembly shown in FIG. 1 .
[0011] FIG. 4 is a schematic view of the integrated signal conditioning electronics of the position sensor assembly shown in FIG. 1 .
[0012] FIG. 5 is a perspective view of a second embodiment of an improved position sensor assembly.
[0013] FIG. 6 is a cross-sectional view of the position sensor assembly shown in FIG. 5 .
[0014] FIG. 7 is an exploded view of the position sensor assembly shown in FIG. 5 .
[0015] FIG. 8 is a block diagram of an embodiment signal conditioning of the position sensor assembly shown in FIG. 1 .
[0016] FIG. 9 is a block diagram of an embodiment of the linearity compensation shown in FIG. 8 .
[0017] FIG. 10 is a block diagram the temperature compensation shown in FIG. 8 .
[0018] FIG. 11 is a block diagram of the initial linearity calibration for the linearity compensation shown in FIG. 9 .
[0019] FIG. 12 is a block diagram of the initial temperature calibration for the temperature compensation shown in FIG. 10 .
[0020] FIG. 13 is a plot of measured and compensated angle (ordinate) vs. actual angle (abscissa) showing linearity compensation.
[0021] FIG. 14 is a plot of measured and compensated angle (ordinate) vs. sensor temperature (abscissa) showing temperature compensation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] At the outset, it should be clearly understood that like reference numerals are intended to identify the same structural elements, portions or surfaces consistently throughout the several drawing figures, as such elements, portions or surfaces may be further described or explained by the entire written specification, of which this detailed description is an integral part. Unless otherwise indicated, the drawings are intended to be read (e.g., crosshatching, arrangement of parts, proportion, degree, etc.) together with the specification, and are to be considered a portion of the entire written description of this invention. As used in the following description, the terms “horizontal”, “vertical”, “left”, “right”, “up” and “down”, as well as adjectival and adverbial derivatives thereof (e.g., “horizontally”, “rightwardly”, “upwardly”, etc.), simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate.
[0023] Referring now to the drawings, and more particularly to FIGS. 1-4 , a position sensor assembly is provided, a first embodiment of which is generally indicated at 15 . As shown, assembly 15 generally includes RVDT 17 , integrated conversion and signal conditioning electronics 28 and housing 16 .
[0024] RVDT 17 is an electromechanical transducer that provides a variable alternating current output voltage that is linearly proportional to the angular displacement of input shaft 35 . When energized by electronics 28 with a fixed AC source 32 , output signal 27 is linear within a specific range over the angular displacement. RVDT 17 generally comprises iron core rotor 23 rotationally supported within cavity 20 of subassembly housing 18 . Stator 22 includes primary longitudinally extending linked excitation coils 24 and a pair of secondary longitudinally extending linked output coils 25 and 26 . A fixed alternating current excitation 32 is applied to primary stator coils 24 , which are electromagnetically coupled to secondary coils 25 and 26 . This coupling is proportional to the angular displacement of rotor 23 and input shaft 35 about axis x-x. Output pairs 25 and 26 are structured so that one coil set 25 is in phase with excitation coils 24 , and the second set 26 is 180 degrees out of phase with excitation coils 24 . When rotor 23 is in a position that directs the available flux equally in both the in phase and out of phase coils, the output voltage is cancelled and results in a zero value signal. This is referred to as the electrical zero position or E.Z. When rotor shaft 23 is displaced from E.Z., the resulting output signal 27 has a magnitude in phase relationship proportional to the direction of rotation. Because RVDT 17 performs essentially like a transformer, excitation voltage changes will cause direction proportional changes to the output (transformation ratio). In this embodiment, a MOOG-MCG-MURPHY AS-827 RVDT may be used.
[0025] As shown in FIGS. 3 and 4 , integrated electronics 28 generally includes circuit board 30 and mezzanine or expansion board 31 . Circuit board 30 includes microcontroller integrated circuit 29 , having configurable blocks 33 and 34 that excite 32 primary windings 24 and filter signal 27 from secondary windings 25 and 26 , and interface 44 . Integrated circuit 29 controls the frequency and amplitude of excitation signal 32 , demodulates signal 27 from the secondary windings, filters to eliminate the carrier frequency, samples and converts 82 the received analog signal 27 into digital format, and calibrates 110 , 120 , compensates 83 , 84 , amplifies, scales and buffers the signal for output 85 . Mezzanine board 31 is provided to allow for custom interfaces, such as a digital interface for a standard digital bus. As shown, circuit board 30 includes additional chip set 58 , which in this embodiment includes temperature sensor 55 , voltage reference chip 56 and oscillator 57 , with outputs to integrated circuit 29 .
[0026] As shown in FIGS. 1-3 , electronics 28 are fully integrated with RVDT 17 in housing 16 such that RVDT 17 and signal conditioning electronics 28 are fully contained and enclosed within the interior cavities of unitary housing 16 . In this embodiment, housing 16 generally comprises sensor housing subassembly 18 having cavity 20 , and electronics housing subassembly 19 having cavity 21 . Sensor housing subassembly 18 is formed by annular bearing end portion 36 , hollow cylindrical body portion 38 and circular intermediate end plate 39 . The left end of cylindrical portion 38 includes inwardly extending double seat 48 , defined by rightwardly-facing annular surface 49 , inwardly-facing cylindrical surface 50 , and rightwardly-facing annular surface 51 . The left ends of coils 24 , 25 and 26 abut against and are axially restrained by surface 49 and the left annular face of bearing 42 abuts against and is axially restrained by surface 51 .
[0027] Annular bearings 42 and 43 , positioned axially along axis x-x on the left and right outer sides, respectively, of cavity 20 , support rotor 23 within cavity 20 of housing subassembly 18 so as to allow rotor 23 to rotate about axis x-x relative to housing 16 . Coil assembly 22 is positioned axially interior to bearings 42 and 43 , respectively, within cavity 20 . Coil 24 is positioned circumferentially between coils 25 and 26 . Thus, bearing 42 , coil assembly 22 and bearing 43 are stacked axially within housing subassembly 18 , with end plate 39 separating cavity 20 from cavity 21 of electronics housing subassembly 19 .
[0028] Electronic housing subassembly 19 generally comprises hollow cylindrical body 40 having circular end plate 41 and forming inner cylindrical cavity 21 . Integrated electronics 28 are stacked axially along axis x-x within cavity 21 of subassembly housing 19 . In particular, circuit board 30 is positioned axially to the right of intermediate housing plate 39 and mezzanine board 31 is positioned axially to the right of board 30 . As shown, each of coils 24 - 26 , bearing 43 , intermediate housing plate 39 , board 30 and mezzanine board 31 has an outer diameter slightly less than the inner diameter of cylindrical housing portions 38 and 40 so as to allow for the axial stacking transversely along axis x-x described above.
[0029] Mechanical threaded stand-off spacers, severally indicated at 45 , provide proper axial spacing of transversely extending boards 30 and 31 in cavity 21 between intermediate housing plate 39 and housing end plate 41 . Electronics subassembly 19 is connected to sensor subassembly 18 by spacers 45 , attached to each other by threaded connections, and machine screws 46 extending through end portion 41 and attached to respective spacers 45 by threaded connections. Thus, housing 16 contains both RVDT 17 and electronics 28 in a fully integrated package.
[0030] Microcontroller integrated circuit 29 is configured to provide initial calibration for inherent non-linearity in the stator 22 , rotor 23 and their mechanical assembly, as well as for thermal non-linearity, of each assembly 15 and to provide operational compensation 80 for such linearity and temperature variations. Thus, compensation routine 80 is directed to producing a linear output signal 85 and is described with reference to FIGS. 8-14 . At step 81 of FIG. 8 , signal 27 is received 81 as an output from RVDT 17 in the form of an AC signal (sine wave) of varying amplitude and phase with respect to excitation signal 32 . Output signal 27 is then converted from analog to digital at step 82 . With respect to the conversion of step 82 , the voltage reference from voltage chip 56 is used to provide an accurate and stable voltage reference in the conversion and the signal from oscillator 57 is applied to provide more accurate timing during sampling. Sampling can be synchronous with demodulation occurring in the analog domain, or sampling can be asynchronous with demodulation occurring in the digital or software domain. The ability of integrated circuit 29 to handle both synchronous and asynchronous sampling provides flexibility regarding execution of the signal acquisition and processing techniques described herein, and further allows for the implementation of all described position sensor assembly 15 embodiments. After demodulation at step 82 , the signal is compensated for linearity at step 83 and temperature at step 84 .
[0031] A method of linear compensation 83 is further shown and described with reference to FIG. 9 . Initially, the system acquires a measured position 91 from the raw position value output from the demodulation and analog to digital conversion at step 82 . From here, the system may perform either of error correction or error lookup at step 92 . Error correction, or polynomial correction, maps the error as a function of a measured position of rotor 23 . Constants are generated, which provide a polynomial fit to the measured error. The generated polynomial can be used to compensate for any error that is present in the measured position. The generated polynomial will take the form:
[0000] Error= a n X n +a n−1 X n−1 + . . . +a 2 X 2 +a 1 X+a 0
[0000] wherein X represents measured position, and wherein the constants a n . . . a 0 are calculated at linear calibration 110 , which is discussed below in greater detail with reference to FIG. 11 .
[0032] Polynomial correction requires less memory than error lookup, but may not be able to compensate all situations. Conversely, utilizing error lookup at step 92 may require more memory than error correction, but error lookup can compensate all situations. Like polynomial error correction, error lookup also maps the error as a function of measured rotor position. However, the measured error is stored directly into a table and is directly looked up at run time. According to one embodiment of the disclosure, a table may be generated which holds all possible position values and all position errors at those values. According to another embodiment, a table may be generated which holds only a portion of the possible position values and position errors, and then linear interpolation or similar techniques may be used to fill in any gaps in the acquired data. In the case of utilizing error lookup at step 92 , the necessary equation will take the form of:
[0000] Error=errorValues[X]
[0000] wherein X represents the measured position. After performing either error correction or error lookup at step 92 , linear compensation method 83 then performs error subtraction at step 93 , wherein a linearized (compensated) position 94 is calculated as being equal to the measured position 91 minus the error (taken from step 92 ). In one embodiment, the linear compensation steps of FIG. 9 may be performed at a production factory, resulting in a position sensor assembly that will be able to be continuously corrected for linear compensation during operation using the factory corrected values. The linearized (compensated) position 94 is a position that has been fully compensated for linear errors in the assembly 15 . However, errors due to temperature may still be present.
[0033] Accordingly, position sensor method 80 of FIG. 8 proceeds to temperature compensation method 84 , which is herein described in detail with reference to FIG. 10 . Initially, linearized position 94 is calculated with respect to the procedure illustrated in FIG. 9 and disclosed hereinabove. At step 101 , temperature of the position sensor assembly is measured. Preferably, the temperature is measured by discrete temperature sensor 55 on main processor board 30 of position sensor assembly 15 . In an additional embodiment of the disclosure, temperature is alternatively measured by means of a thermistor embedded within stator 22 , or by any other thermal transducer or sensor disposed at any other location within housing 16 .
[0034] After receiving linearized position 94 and a measured temperature (from step 101 ), temperature compensation method 84 proceeds to step 102 , wherein either polynomial error correction or error lookup is performed. The procedure of step 102 is substantially the same as the error correction/lookup step 92 described with reference to FIG. 9 hereinabove, however constants a n . . . a 0 (if using error correction) and/or position errors (if using error lookup) used in the corresponding error calculations will have been determined during temperature calibration 120 (as opposed to during linear calibration), discussed below in more detail with reference to FIG. 12 .
[0035] Temperature compensation method 84 next proceeds to step 103 , wherein a temperature compensated position 104 is calculated by subtracting the error calculated in step 102 from linearized position 94 . In one embodiment, the temperature compensation steps of FIG. 10 may be performed at a production factory, resulting in a position sensor assembly that will be able to be continuously corrected for temperature compensation during operation using the factory corrected values. The resulting compensated position 104 is a position that has now been fully compensated for both linearity errors in the sensor in addition to errors resulting from fluctuations in the sensor temperature.
[0036] Referring back to FIG. 8 , compensated position 104 is now stored within memory 59 of microcontroller integrated circuit 29 as compensated output 85 . In a preferred embodiment, integrated circuit 29 comprises an internal digital register 59 to store the compensated output 85 , which may then be presented to a user via mezzanine board 31 as an analog or digital signal via RS-232, RS-48, CAN, USB, SPI, I2C, or any other means of signal delivery as known in the art.
[0037] Turning to FIG. 11 , a process of linearity calibration 110 is disclosed. Position sensor assembly 15 is driven by an external actuator 111 through its entire position range while the temperature is held constant at a preferred 25 degrees Celsius, though any other suitable temperature may be used. An external reference position 112 for rotor 23 is provided to the system, preferably taken from a previously calibrated high resolution reference. Next, the system determines a sensor measured position 113 and compares this position to the known good reference position 112 in order to calculate a detected error 115 . The detected error 115 is then preferably processed and/or stored in memory 59 in step 116 , wherein depending on the type of compensation method being used (error correction or error lookup), polynomial constant(s) will be either generated for immediate output or stored in memory 59 in a lookup table for future use at step 117 .
[0038] Temperature calibration process 120 is now disclosed with reference to FIG. 12 . Position sensor assembly 15 is driven by an external actuator 121 , wherein the sensor may be driven through its entire position range. Alternatively, the sensor may be held in a stable position. Position sensor assembly 15 is then subjected to external temperatures over its entire temperature range, while the system measures and records the sensor position 123 and temperature 124 . The measured position 123 and measured temperature 124 of the sensor are then compared to a known good reference position at a preferred 25 degrees Celsius 122 , in order to calculate a detected error 125 . Similarly to the linearity calibration method 110 , the detected error 115 of temperature calibration method 120 is then preferably processed and/or stored in memory 59 in step 126 , wherein depending on the type of compensation method being used (error correction or error lookup), polynomial constant(s) will be either generated for immediate output or stored in memory 59 in a lookup table for future use at step 127 .
[0039] FIG. 13 is a plot of measured and compensated angle (ordinate) vs. actual angle (abscissa) showing linearity compensation at a preferred constant temperature of 25 degrees Celsius. Solid line 131 illustrates an embodiment of measured positions of the sensor, while the dotted line 132 illustrates the preferred positions compensated for linearity. FIG. 14 is a plot of measured and compensated angle (ordinate) vs. sensor temperature angle (abscissa) showing temperature compensation at a preferred constant rotor angle of 30 degrees. Solid line 141 illustrates an embodiment of measured positions of the sensor, while the dotted line 142 illustrates the preferred positions compensated for temperature.
[0040] The integration of the electronics and the use of a digital interface provides for improved noise immunity, reduces system weight and cost and provides ease of integration. The use of a digital bus interface also allows for a chaining of multiple devices. The output of assembly 15 can provide both position and rate information. Assembly 15 thereby simplifies the integration of an AC RVDT position transducer device by integrating the necessary conversion and conditioning electronics 28 in the body or housing 16 of the device. Integrated electronics 28 provide the excitation to the primary windings, demodulation of the secondary windings, conversion of the demodulated AC signal to a DC signal, provide amplification of the DC signal, provides for hardware/software signal filtering, and compensates for nonlinearity in the signal from the RVDT. The output signal of assembly 15 can be DC voltage or current or any standard digital bus signal. For fly-by-light applications, assembly 15 can also integrate a fiber optic front end.
[0041] While a RVDT sensor is shown and described in this embodiment, it is contemplated that other high reliability rotary or linear transducer types can be employed, including but not limited to resolvers, synchros and linear variable differential transformers (LVDTs). In an LVDT embodiment, coils 25 and 26 may be oriented annularly about axis x-x and coil 24 may be positioned axially between coils 25 and 26 such that bearing 42 , coil 25 , coil 24 , coil 26 and bearing 43 are stacked axially within housing subassembly 18 , with end plate 39 separating cavity 20 from cavity 21 of electronics housing subassembly 19 .
[0042] A second embodiment 115 is shown in FIGS. 5-7 . This embodiment is generally the same as assembly 15 but differs in that housing 116 is not formed from two connected subassemblies and does not include intermediate housing portion 39 , as in assembly 15 . Rather, housing 116 is formed from a longer cylindrical body portion 118 and a circular end plate 141 fixed to the annular right end of cylinder 118 and has a unitary inner cavity 120 .
[0043] While the presently preferred form of the improved position sensor assembly has been shown and described, and several modification thereof discussed, persons skilled in this art will readily appreciate the various additional changes and modifications may be made without departing from the scope of the invention, as defined and differentiated by the following claims. | A position sensor assembly comprising ( 15 ) a housing ( 16 ) having a least one inner cavity, a stator ( 22 ) disposed within the housing, a moving element ( 23 ) disposed within the housing and configured and arranged to move relative to the stator ( 22 ), the stator comprising primary windings ( 24 ) and secondary windings ( 25, 26 ), the secondary windings configured and arranged to provide an output signal ( 27 ) as a function of movement of the moving element ( 23 ) relative to the stator ( 22 ), electronics ( 28 ) disposed in the housing and communicating with the primary windings ( 24 ) and the secondary windings ( 25, 26 ), the electronics comprising an integrated circuit ( 29 ) configured and arranged to provide excitation of the primary windings ( 24 ) and to demodulate the output signal ( 27 ) of the secondary windings ( 25, 26 ), and an input element ( 35 ) extending through the housing ( 16 ) and connected to the moving element ( 23 ). | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims the benefit under 35 U.S.C. §119 (e) of the U.S. Provisional Patent Application Ser. No. 61/476,660 filed on Apr. 18, 2011.
FIELD OF THE INVENTION
The invention relates to an exoscope for observing and illuminating an object field on a patient from a site outside the patient's body, with a lens system for observing the object field and with an illumination to illuminate the object field, a distance between lens system and object field can be modified by a bracket.
BACKGROUND OF THE INVENTION
Apparatuses for illuminating an object field in an OR and also apparatuses for observing the object field are known in a variety of configurations.
From WO 2004/100815 A2, a surgical field illumination apparatus is known that comprises a large-surface illuminating unit and an integrated optic observation device. Here the observation device in particular can be a surgical microscope. This makes it possible to work with an optical observation device without requiring the presence of a tripod and a bracket for the optical observation device in addition to the tripod and bracket for the surgical field illumination. The apparatus is very unwieldy in structure and occupies a relatively large amount of space in the area above the object field.
Surgical microscopes for microsurgical disciplines are known under the designation M651 from the company Leica Microsystems AG, in Heer-brugg, Switzerland. These surgical microscopes are equipped with a built-in illumination by which the surgical site can be illuminated. This surgical microscope is also very unwieldy in structure, in particular because it comprises a very wide bracket in order to be able to bring the surgical microscope into numerous different positions relative to the object field. Surgical microscopes have a low depth of field, and thus in modifying the working distance it is often necessary to refocus.
Solutions have therefore been sought to provide apparatuses for observing and illuminating an object field that are less unwieldy and that in particular disturb the surgeon or possibly several persons participating in such an operation.
From WO 2008/153969 A1, an apparatus is known that is oriented to a configuration of an endoscope as is frequently used in minimally invasive surgery.
Endoscopes are thin elongated apparatuses with a relatively long, thin shaft. Integrated in the shaft is a lens system, in most cases a lens system made up of several long, thin rod lenses, a so-called HOPKINS rod lens system. Illumination consists in most cases of lighting lines fed in the shaft, said lines conducting light from a light conductor connection on the proximal side through the shaft as far as its proximal end.
The inner hollow spaces that are to be illuminated during minimally invasive surgery are relatively small, so that light of relatively low strengths is sufficient to illuminate such a surgical field, whether in laparoscopy inside an abdominal space or in arthroscopy in relatively small areas between joints.
The surgical site can be observed by the lens system. In visual observation, an eyepiece is provided on the proximal end of the shaft. The applicant itself in the past forty years has made a considerable contribution to further developing the technology of rigid endoscopes, with the result that the lens system makes possible a markedly sharp observation through such a shaft with the lens system mounted inside it.
In a refinement of this technology, a video camera was connected at the proximal end of the endoscope, said video camera recording the image and displaying it on a monitor. This led to a transformation of minimally invasive surgical technology in that surgeons are no longer required to keep their eye on the eyepiece during a procedure and thereby to observe the processes carried out inside the body but instead observe this on a monitor. In difficult operations and especially those that last for some time, it becomes less tiring for the surgeon to observe an image on a monitor rather than constantly gazing through an endoscope with one eye.
This technology requires intensive training on the part of the surgeon, because he is observing in fact the processes he himself performs inside a body, not through an endoscope positioned directly in front of him but rather via a monitor positioned outside and laterally removed from the surgical site. This requires a relatively lengthy practice phase, but then leads to the surgeon being able to perform minimally invasive procedures in a relatively relaxed position, whether standing or seated. This applies likewise to supporting staff or assistants who are now not required to observe the surgical site through additional trocars placed in the body with lens systems inserted through them, but who instead can now observe this on one and the same monitor.
This technology now makes it possible to visually record and store the entire operation procedure. The digitally stored image, at the same time, can also be exchanged with other hospitals, and in fact this is also possible live during a procedure. Consequently, specialists can be actively involved in an operation, directly viewing the image captured by the video camera so that they then can lend support to the surgeon.
In the aforementioned WO 2008/153969 A1, an attempt was made to create apparatuses for extracorporeal visualization in medicine on the basis of this type of endoscope.
This apparatus is mounted by means of a bracket in such a way that, through the lens system, an object field can be observed at a distance of a few centimeters, such as in the range of 20 cm, from the distal light outlet or image entry end. The optical properties were adjusted accordingly for this working distance. The term “exoscope” is derived from this fact; that is, meaning an observation instrument based closely on successful invasive endoscope technology but serving for extracorporeal illumination and observation of an object field.
It was observed in practical use that endoscopes of this type, for reasons inherent to the system, were subject to certain restrictions. If the distances between the lens and the object field are relatively large, such as more than the previously mentioned 20 cm, the object field can no longer be sufficiently observed and the lens no longer conveys an optimal image.
If one assumes, for example, an open heart operation in the chest area, then the sternum must first be sawed along its entire length and spread wide apart by means of so-called rib retractors. Only then is there any access at all to the inner sternum area and/or the still beating heart. These rib retractors are mechanically very stable tools, which are relatively unwieldy and accordingly demand a sufficiently large space for manipulation over the object field. This requires a certain minimum distance from the observation lens.
In an actual open-heart surgery intervention, after the preparation, that is, once the sternum has been sawed open, the sternum spread apart, and the heart exposed, relatively large areas are observed and illuminated. At the end of such an operation, for example after replacement of coronary vessels, very minute manipulations must be performed and relatively small areas must be observed and illuminated, for example if vessel implants must be sewed and affixed to the heart wall on existing vessels. The observation lens is required to provide an optimal image in each case in all surgical steps.
SUMMARY OF THE INVENTION
It is therefore the object of the present invention to further develop an exoscope for the purpose of providing a stable, robust structure and ensuring that an object field can be sufficiently illuminated and observed at distances that extend to the meter range.
This object is achieved according to the invention by means of an exoscope that comprises a shaft on whose distal end a head member is positioned that is wider than the diameter of the shaft, the illumination reaches into the distal side of the head member and it is possible to position in the head member at least one radiating illuminating unit whose radiant characteristic can be selected in that the object field can be homogeneously illuminated at all possible distances from the lens and wherein power lines are positioned in the shaft for the at least one illuminating unit.
These measures have numerous advantages for the use of an exoscope. Providing a head part that is wider than a shaft makes it possible to configure the shaft in all cases as a relatively thin structure and thus not cumbersome or of wide configuration. By providing a head member that is wider than the shaft, it becomes possible to integrate a sufficiently powerful illumination therein, which can also homogeneously illuminate surgical sites in great distances up to a meter. The head member is markedly larger and in particular wider than the shaft, in particular by a multiple.
A radiation direction occurring under an angle from the longitudinal axis of the shaft opens to mount the exoscope in an inclined or horizontal extension to an object filed. This advantageously provides more space at the object field for the surgeon to operate and use instruments without impacting a vertically positioned exoscope.
In one embodiment, the depth of the head member is about the same as the diameter of the shaft. This provides more space around the head area of the exoscope for the surgeons to operate.
Additionally, guiding the light conductors within the shaft avoids unnecessary junctions for connecting with light connectors of other parts. This results in a marked reduction in light loss in the areas of such junctions. This allows for most of the light to effectively be used to illuminate the operation site.
Because the power lines for illumination are integrated in the shaft, there are no exposed power lines running from the distal to the proximal end that would not only require additional structural space but also would include the risk that staff might become entangled therein. Because the head member is enlarged in comparison with the shaft, it is possible to integrate or position therein one or more radiating illuminating units, so that a radiant characteristic can be selected that allows homogeneous illumination over the entire range of variable distances.
This has the advantageous consequence that the head member can be positioned at a relatively small distance of just a few centimeters from the object field and in addition that the object field can thereby be optimally illuminated, in particular homogeneously, and this is also possible even when the head member is at a considerable distance, such as a meter, away, requiring working distances preferably of 20 to 60 cm. Accordingly powerful illuminating units must be provided that also generate the corresponding heat, and thus the head member must make it possible to integrate such components, to convey them and to incorporate them in good working order.
The head member also allows other components to be integrated such as filters, diaphragms or the like, to make it possible to conduct medical procedures such as photodynamic therapy, photodynamic diagnosis, autofluorescent methods or ICG (indocyanine green) examination. The optical system itself is designed to provide an optimal image at all times over the entire variable working distance, whereby the working distance can vary from about 20 cm to about 1 m, preferably up to 60 cm. The lens system, depending on its design, can be integrated into the shaft, but in such case the distal end of the lens system likewise is positioned in the head. This makes possible varying positions of the radiating illumination units relative to the distal end of the lens system.
When there is only one illuminating unit, the distal end of the lens system can be positioned in the axial direction of the shaft upstream or downstream from the illuminating unit, or these components can also be positioned beside one another.
Assuming a configuration with two illuminating units, they can be positioned on both sides of the distal end of the lens system; with more than two radiating illuminating units, they can be positioned around the distal end of the lens system. This depends on the purpose for which the exoscope is being used, that is, whether it is intended to illuminate relatively small or large object fields. Depending on the configuration of the illuminating units, necessary power lines can be fed through the shaft to the head member. If illuminating light is generated directly in the head member, for example by light diodes, the electric lines can be fed through the shaft. If the light is fed through light conductors, they can be placed in the shaft.
In another configuration of the invention, the radiating illuminating units are equipped with focusing that comprises condenser lenses.
This feature has the advantage that the head member also integrates a focusing device whereby optimal focusing of the illuminating light can be achieved for the particular object field. In this case each illuminating unit can comprise its own focusing device, and with several illuminating units, all of them or groups of them can be equipped with a common focusing device. The radiant characteristic or homogeneous illuminating depth can be pre-selected as a default setting by the manufacturer.
In another configuration of the invention the light beams, which can be emitted by the several radiating illuminating units, can be adjusted in such a way that the light beams overlap so that the surgical site can be illuminated homogeneously by the overlap area.
Not only does this contribute to an optimal illumination of the surgical site or object field, but also the control and operation are relatively simple. Corresponding adjustment devices, for example focusing devices or the like, can be mounted in or on the head member because a sufficiently stable base is present in the exoscope to incorporate such additional components and also to operate them. Consequently, optimal illumination is achieved at varying working distances, in particular in the preferred range of 20 to 60 cm.
In another configuration of the invention the illuminating units comprise distal ends of light conductors, which are fed from a proximal light conductor connection via the shaft into the head member.
This feature has the advantage that the actual light source can be positioned off to the side of the exoscope, and thus the surgical area is not encumbered and the light can be directed by the light conductors to the particular illuminating unit.
In another configuration of the invention the light conductors are fed in the shaft as a skein and include strands in the head member that lead to the particular radiating illuminating unit.
This feature has the advantage that the shaft makes possible a relatively slender structure, and separation or fanning into various strands is possible in the enlarged head member.
In an additional configuration of the invention a viewing angle of the lens system and a radiating direction of the illuminating unit occur in the direction of a longitudinal axis of the shaft.
This feature has the advantage that the exoscope can be set up to stand above a surgical site, and when the OR is suitably configured the bracket can be configured so that the exoscope can be positioned suspended from a ceiling. This arrangement is especially favorable during an actual intervention when it is not absolutely necessary to work intensively in this direction, that is a direction standing perpendicular above the surgical site. If a video camera is connected on the proximal end of the lens system, it makes sense to select the working distance in such a way that a person standing at the operating table can operate the camera.
In another configuration of the invention, the viewing angle of the lens system and a radiating direction of the illuminating units are at an angle to the longitudinal axis of the shaft.
The advantage of this feature is that with an exoscope in a stationary position for example, lateral areas of a body can be illuminated, for example during hip surgery with a patient lying on the back. Another advantage of this configuration consists in now positioning the shaft itself at an incline and to leave both the viewing direction of the lens system and the radiating direction of the illuminating device u unchanged in vertical direction. This configuration is used when wide-ranging manipulations are required across the surgical area. With a viewing angle of the lens system that is not equal to zero degrees, the shaft, video camera, light conductors, cables, and so on are no longer directed toward the surgeon but instead can run laterally. As a result, the surgeon is less restricted in his freedom of movement and has a freer view.
In an especially advantageous configuration of the invention, the angle is approximately 90 degrees.
In the 90 degree configuration the exoscope or the shaft can be directed to point approximately horizontally away from the object field and never-theless the object field can be illuminated and observed from above, that is in vertical direction. If a video camera is connected to the lens system, its operating elements are positioned at a height that is favorable for operating staff, so that it can be controlled in ergonomic manner.
In another configuration of the invention the radiating direction is diverted through at last one prism or mirror inserted in the head member.
This feature has the advantage that the prism or mirror provided for the diversion can be positioned directly in the head member. As a result, the illuminating light can be directed for example through the straight shaft into the head member and then diverted there through correspondingly configured prisms.
In another configuration of the invention the radiating direction is diverted through corresponding curvature of the distal end areas of flexible light conductors.
The advantage of this feature is that the flexibility of light conductors, for example those made of glass fibers, can be exploited to achieve the corresponding diversion of the illuminating light away from the longitudinal axis of the shaft in simple manner. Here again, the configuration of the head member as wider than the shaft is favorable, because in this wider head member these curved segments can be incorporated so as to be protected from outside.
In another configuration of the invention the lens system is configured as a separate component that can be inserted into the head member.
This feature has the notable advantage that the illuminating part of the exoscope and the lens system are configured as two different components that can be combined to form the complete exoscope. It is known in the endoscope art how to configure such lenses as autoclavable, and therefore one can have direct access here to a wealth of experience with this technology. Not only does this configuration simplify the installation, disassembly, and cleaning of the exoscope, but it also opens up numerous possible variations. Thus, the illuminating part of the exoscope can be configured as a kind of base member into which various lenses with different optical properties can be inserted. Examples of these optically diverse properties can be different depths of field or different enlargements of the lens systems. It is also possible of course to configure the illuminating part with corresponding variety and to connect it with standard lens systems. Such a configuration will be useful when illuminating systems of varying power are desired but when basically unchanged optical properties are desired or sufficient for the lens system.
This markedly increases the range of application of such an exoscope.
This modular construction makes it possible to provide correspondingly suitable combinations of illuminating parts and lens parts for a particular operation, even in the preparatory stage in assembling the surgical instruments.
In another configuration of the invention a guide device is present on the shaft through which the lens system can be connected to the head member.
This feature has the advantage that in modular construction the lens system can be directed to the head member through the guide device with accuracy and seated precisely.
In another configuration of the invention a base member is present that can be coupled with the lens system.
The advantage of this feature is that the base member can be called on during use independently of the lens system.
The lens system can thus be mounted in a position that is most favorable for observation.
Then the base member with the illuminating units can be installed off to the side, that is, apart from the lens system in a position that is especially favorable for the illumination. These parts can of course be combined and also used together. Flexibility is increased precisely by the fact that these module parts can be separated from one another and can be positioned in the surgical field correspondingly separate from one another.
In another configuration of the invention the base member is composed of modules that already comprise at least an illuminating unit and its power lines.
The advantage of this feature is that here the flexibility is increased still further. Each module part comprises a shaft and at least one illuminating unit. Thus it is possible to position several such module parts with one or more illuminating units at various points in the surgical field, depending on the which of these arrangements is most favorable for an optimal illumination.
These parts too can of course be combined and, as mentioned before, can be used in combination. They can also be stored and kept ready in this condition, and only when the particular application requires it can the module parts be used singly or combined in groups, depending on what is best suited to the field of application. If one location in the surgical area must receive especially intensive illumination during a procedure, then one module part with one or more illuminating units can be removed from the exoscope assembly and be specifically conveyed either by hand or by a bracket to this site that is to be illuminated. When no longer needed, it can be combined again with the other components.
In another configuration of the invention, every module comprises a shaft and a head member, which can be affixed to one another by a separable fastening.
Advantageous in this feature is the fact that every module part has the characteristic of the exoscope, that is, the slender shaft and widened head member, and that, by means of a fastening, all modules as well as the lens system can be used either together or partly joined together.
This increases the flexible uses of such an exoscope.
In another configuration of the invention the head member is configured as a closed housing, which is connected with the shaft on the proximal side.
This feature has the advantage that this sealing prevents penetration of contaminants into the interior of the head member. Thanks to a corresponding hermetic sealing, the head member can likewise be autoclavable, whether as a modular individual part or in assembled state or firmly positioned with a lens system.
In another configuration of the invention the lens system comprises a video camera that is coupled to it and that is connected with a monitor to display the images from the video camera.
The advantage of these features is that the observation technique that is familiar from minimally invasive surgery in connection with endoscopes and has by now become established, can also be used directly on an exoscope. Video cameras in the meantime can be produced in extremely small sizes and with relatively light weight, so that coupling a video camera to the proximal end of the exoscope is simple and can be accomplished without disturbing stability or operating security. This position also lies, in most cases, relatively apart from the surgical area, and thus because of the video camera and its required power lines and cables, no adverse effects occur. Familiar standard connections can be used here in order to couple the video camera to the eyepiece.
The video camera can perform an enlargement in simple manner, namely by the zoom. Complex optical components, in addition, are required for surgical microscopes and can make the device cumbersome and expensive.
In another configuration of the invention the lens system comprises an eyepiece enlargement by which a full-surface image can be achieved on the monitor at all zoom settings of the video camera.
In the predominantly round optical instruments a circular-shaped diaphragm is present. Projected onto a rectangular monitor, parts of the monitor remain black in the corner areas. To make full use of the monitor for the video image, in particular at 16:9 formats, the zoom characteristic is adjusted so that a diaphragm is not visible even at 1× zoom.
It is understood that the characteristics cited heretofore and those that are yet to be described can be applied not just in the indicated combinations but also in other combinations or independently, without departing from the framework of the present invention.
The invention is hereinafter described in greater detail with reference to a few embodiments in connection with the appended drawings, which are as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a bottom view of one advantageous embodiment of the exoscope;
FIG. 2 shows a side view of the advantageous embodiment of FIG. 1 ;
FIG. 3 shows a perspective view of an embodiment of an exoscope from diagonally below, that is, approximately contrary to the radiation or viewing direction of the lens system;
FIG. 4 shows corresponding perspective view from above;
FIG. 5 shows a perspective view of the base member of the exoscope with the lens removed;
FIG. 6 shows a perspective view of the lens removed from the base member of FIG. 5 ;
FIG. 7 shows a longitudinal section along the line V-V in FIG. 6 ;
FIG. 8 shows a strongly schematized longitudinal section through the base member as seen in FIG. 5 , that is, without the lens system inserted and in particular to show the guidance of the light conductors;
FIG. 9 shows a perspective view comparable with that of FIG. 3 of a second embodiment of an exoscope;
FIG. 10 shows a perspective overhead view of the exoscope of FIG. 9 ;
FIG. 11 shows an overhead view of the exoscope of FIG. 9 ;
FIG. 12 shows a section along the line X-X in FIG. 11 ;
FIG. 13 shows a section along the line XI-XI in FIG. 11 ;
FIG. 14 shows a perspective view of a third embodiment of an exoscope facing straight ahead;
FIG. 15 shows, strongly schematized, a possible arrangement of the exoscope of FIG. 13 held in vertical alignment by a bracket;
FIG. 16 shows a strongly schematized view of a fourth embodiment of an inventive exoscope with 90 degree view, similar to the configuration of the second embodiment but coupled with a video camera that transmits an image onto a monitor;
FIG. 17 shows a fifth embodiment of an exoscope with only one illuminating unit and 90 degree view;
FIG. 18 shows a longitudinal section in the area of the head member of FIG. 17 ;
FIG. 19 shows an exploded view of a sixth embodiment of an exoscope in modular structure;
FIG. 20 shows the distal end area of the exoscope of FIG. 19 in assembled state;
FIG. 21 shows a section along the line XIX-XIX in FIG. 20 ;
FIG. 22 shows a possible application of the module components in a surgical area; and
FIG. 23 shows a seventh embodiment of an exoscope with laterally displaced illumination units.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views.
An embodiment of the exoscope 10 is illustrated in FIGS. 1 and 2 . Another embodiment of the exoscope 10 is shown in FIGS. 3-8 . It should be understood that the structure and function of the exoscope 10 in FIGS. 1 and 2 is similar to that illustrated in FIGS. 3-8 . Accordingly, the two embodiments will be described together with the differences between the embodiments specifically discussed.
The exoscope 10 comprises a lens system 12 . The lens system of the embodiment of FIGS. 1 and 2 has the lens system mounted fixedly. The lens system of the embodiment of FIGS. 3-8 is configured as a modular, self-contained component.
One notable difference from the embodiment in FIGS. 1 and 2 and that of FIGS. 3-8 is the low profile head member 20 . FIGS. 1 and 2 illustrate a head member 20 that has a depth that is almost equal the diameter of the shaft 16 , which can be seen in FIG. 2 .
Another difference from the embodiment shown in FIGS. 3-8 is that, the skein 31 of the light conductors in FIGS. 1 and 2 does not have bended branches as shown in FIG. 4 at 32 and 34 . Rather, the light guides in the embodiment of FIGS. 1 and 2 extend straight into the head member 20 and light is directed about 90 degrees via a prism integrated into the head member 20 (see FIG. 13 in particular for the construction of the integral prism).
One of the advantages of the low profile head embodiment is that the head member 20 is very thin and the fiber bundle is guided within the shaft 16 to the head member 20 . The chances of the fiber bundles becoming damaged is therefore reduced.
In addition, the exoscope 10 comprises a base member 13 , in which the illumination 14 is integrated. The base member 13 comprises an elongated, approximately half-bowl-shaped rigid shaft 16 whose distal end 18 is connected with a head member 20 .
Integrated in the head member 20 is a first illuminating unit 22 , which emits light in a radiating direction 23 . In addition, a second illuminating unit 24 is also positioned in the head member 20 and likewise emits light in a radiating direction 25 . As can be seen in particular from the sectional view of FIG. 8 , supply lines 26 are positioned inside the base member 13 to convey illuminating light to the illumination units 22 and 24 . Provided for this purpose is a light conductor connection 30 , which is positioned laterally from the proximal end of the shaft 16 and in which a skein 31 of light conductors 28 is inserted. The skein 31 is composed of a bundle of numerous flexible glass fibers, known per se from the field of endoscope construction. This skein 31 is fed in the shaft 16 as far as the head member 20 , where it is separated, as can be seen in particular from FIG. 4 , into two branches 32 and 34 , which lead respectively to the illuminating units 22 and 24 . Situated on the underside, that is, on the radiating side of the head member 20 , is a corresponding radiation opening 36 , which is hermetically sealed off by an optically active window 40 .
The head member 20 comprises a housing 38 that is closed on all sides and firmly connected with the rigid shaft 16 .
As can be seen in particular from FIG. 8 , a focusing device 44 , integrated in the head member 20 , comprises slidable condenser lenses 46 in order to achieve a focusing of the illuminating light.
The housing 38 is as a rule sealed for insulation and thus autoclavable. The condenser lens 46 also ensures that the individual light conductors are not configured but rather that the illumination field is homogeneous. The producer in most cases already provides the settings, which the user cannot modify. However, should a movement of the condenser lenses be desired, integrated positioning organs can also be installed in the head member 20 , for example positioning rings or positioning discs that can be operated from outside and whose rotation produces a back-and-forth sliding of the condenser lenses 46 in the illuminating direction 23 .
It can be seen from the drawings in FIGS. 3 through 5 that the radiating directions 23 and 25 of the illuminating units 22 and 24 run diverted at an angle of about 90 degrees from the longitudinal axis 48 of the shaft 16 .
It can be recognized in particular from FIGS. 3 and 5 that a guide device 50 for the lens system 12 is provided on the base member 13 . The guide device 30 comprises on the proximal end of the shaft 16 a hollow guide sheath 52 , from which the lateral light conductor connection 30 also extends outward. The proximal end of the head member 20 is configured as a type of duct 54 into which the distal end section of the lens system 12 can be inserted.
During assembly, the lens system 12 , as seen in FIG. 6 , is advanced from the distal to proximal side through the housing 52 along the shaft 16 in distal direction until the distal end portion is inserted into the duct 54 as seen in FIG. 3 . A coupling site 63 on the lens system 12 ensures a particular rotation direction for the lens system 12 with respect to the base member 13 .
The lens system 12 itself, as can be seen in particular from FIGS. 6 and 7 , comprises an elongated lens shaft 62 on whose proximal end an eye-piece 64 is screw-mounted.
Enclosed within the lens shaft 62 is a lens system 66 , for example a rod lens system known from the endoscope construction art according to HOPKINS. Positioned on the distal end 68 of the lens system 66 is a prism 70 that ensures that a viewing direction 74 results, at an angle 76 of approximately 90 degrees from the longitudinal axis 72 of the lens shaft 62 . A corresponding transparent window 78 closes off the lens shaft 62 laterally in this area of the viewing direction 74 . The prism 70 can be assembled of several prisms.
As can be seen in particular from the perspective view in FIG. 3 , the window 78 then is at such a position that the viewing direction 74 is approximately aligned with and parallel to the radiating directions 23 and 25 of the illuminating units 22 and 24 .
This configuration of the exoscope 10 with a 90 degree angle and 90 degree illuminating direction with respect to the longitudinal axis of the shaft 16 is applied when, as shown in FIG. 4 , an object field 56 is to be illuminated and observed in which the exoscope 10 is intended not to take up too great an area of the object field 56 . The exoscope 10 is held and directed by a bracket, not presented in any greater detail here, in such a way that it extends diagonally to the surface of the object field 56 away from the surgical site.
A second embodiment of an exoscope, shown in FIGS. 9 through 12 , is designated in its entirety with reference number 80 . Here too the exoscope 80 comprises a lens 82 and an illumination 84 . Here as well, an elongated cylindrical shaft 86 , closed and hollow in this embodiment, is foreseen with a head member 90 mounted on its distal end 88 . A first illuminating unit 92 as well as a second illuminating unit 94 is also positioned in the head member 90 . Here, again, the radiating direction 93 of the illuminating unit 92 as well as the radiating direction 95 of the illuminating unit 94 is directed in such a way that it runs at an angle of approximately 90 degrees to the longitudinal axis 87 of the shaft 86 .
The lens 82 is inserted from the proximal end into a guide tube 100 of the shaft 86 and is firmly connected with the head 90 , as can be seen in FIG. 12 .
The lens 82 too is once again configured as a 90 degree lens, that is, its viewing direction 83 , as can be seen in particular from FIG. 9 , runs at a 90 degree angle to the longitudinal axis 87 of the shaft 86 , in which the shaft of the lens 82 , not presented in greater detail here, is inserted. Here too the arrangement is such that the lateral window, by which the 90 degree view is made possible, is positioned in the head member 90 and also positioned, as can be seen in particular from FIG. 9 , between the two illuminating units 92 and 94 . The lens 82 is equipped with an eyepiece 98 .
A light conductor connection 102 protruding laterally from the proximal end of the shaft 86 serves, again, to contain light conductors 104 , which, as visible in the sectional drawing of FIG. 12 , are positioned in an intermediate space 105 between the outer shaft 86 and the guide tube 100 and are fed in distal direction to the illuminating units 92 and 94 .
It can be seen from the sectional drawing in FIG. 13 that a prism 108 is positioned in the head member 90 and diverts illuminating light fed by the light conductors 104 at a 90 degree angle from the longitudinal axis 87 into the radiation direction 95 . A lens inserted in between ensures that this illuminating light diversion occurs with as little divergence loss as possible. Instead of the prism 108 a mirror 109 can be used for diverting the illuminating light.
It can be seen in particular from the perspective drawing in FIG. 9 that the two illuminating units 92 and 94 and the inlet of the lens 82 positioned between them are positioned in the viewing direction 83 in a row that runs diagonally to the longitudinal axis of the shaft 87 .
It is also possible to direct this row in such a way that it runs in the direction of the longitudinal axis 87 . Here the row can lie directly in the direction of the longitudinal axis 87 , or it can be displaced laterally to left or right so that with certain operating techniques, if desired, working space is made available immediately beside the head member 90 on one side of the longitudinal axis 87 . It is not essential here that these three structural elements lie on a straight line but they can instead lie on a curved line. In the embodiments in which more than two illuminating units 92 and 94 are foreseen, for example with three or four, they can be positioned accordingly around the distal end of the lens 82 .
Illustrated in FIGS. 14 and 15 is a third embodiment of an exoscope, which is designated in its entirety with the reference number 110 . The exoscope 110 also comprises a lens 112 that is enclosed in a shat 114 . The viewing direction 113 of the lens 112 here follows the direction of the longitudinal axis 115 of the shaft, and is thus a lens 112 with a zero degree viewing angle. Here too, once again, positioned on the proximal end of the shaft 114 is a head member 116 in which two illuminating units 118 and 120 are enclosed whose radiating directions 119 and 121 are likewise aligned in the direction of the longitudinal axis 115 . FIG. 15 shows how the exoscope 110 is mounted on a stationary site 142 by means of a bracket 134 . This site is usually the operating table or a special tripod.
For this purpose the bracket 134 can comprises a multiply jointed arm 136 that is connected with the shaft 144 by a clamp 138 . A screw 140 allows a separable connection between the bracket 134 and endoscope 110 , where the latter can be displaced upward.
As can be seen from the depiction in FIG. 15 , two light beams 123 , 126 are radiated from the illuminating units 118 , 120 and are directed in such a way that they intersect. This allows illumination of both a relatively remotely situated object field 130 and a relatively closely situated object field 128 in optimal manner, that is homogeneously. The depiction in FIG. 15 is not true to scale; the maximum distances between the illuminating units 118 and 120 and the corresponding object field can lie in the range of 1 m. This arrangement with the zero degree lens and the corresponding illuminating direction is selected when sufficient space is available extending over the particular object field.
In the fourth embodiment shown, in FIG. 16 , an exoscope 80 ′ is employed that, where the configuration of the shaft, illumination supply, and the diversion is concerned, is of the same configuration as the embodiment of an exoscope 80 shown in FIGS. 9 through 12 . Contrary to this second embodiment, there is a video camera 150 coupled on the eyepiece and connected by a cable 151 with a monitor 152 . The exoscope 80 ′ is connected by a bracket 156 to a wall 158 . A light conductor connection 161 extending in the proximal direction is connected with a power line 162 that leads to a light source 164 set off to the side. Here too the illuminating units are arranged in such a way that a light beam 170 results that optimally illuminates an object field 154 . Located in the illustrated embodiment in an object field 154 is an organ, for example a beating heart, on whose outer arteries 174 a surgical procedure is to be performed in the area of a branching 176 . Arrows 166 , 167 , 168 indicate that the object field 154 is accessible without obstacle to a surgeon or support staff. For all these persons there is the possibility of observing the object field 154 visualized on the monitor 152 .
At the beginning of the operation, if the sternum is first to be opened and the organ 172 to be accordingly exposed, then the bracket 156 can hold the exoscope 80 ′ positioned in such a way that the entire sternum area is illuminated over its surface. If then, for example at the branching 176 , a procedure is to be performed, then either a corresponding focusing can be accomplished on this site by the video camera 150 or the exoscope 80 ′ or its head member 90 can be moved closer to the object field 154 by the bracket 156 . In all positions an optimal illumination and an optimal visual monitoring of the surgical process are possible.
Illustrated in FIGS. 17 and 18 is a fifth embodiment of an inventive exoscope, which is designated in its entirety with reference number 180 .
Here again the exoscope 180 comprises a base member 184 in which a lens 182 is enclosed. An eyepiece 183 is present at the proximal end.
The viewing direction 185 of the lens 182 runs at a 90 degree angle to its longitudinal axis.
The lens 182 is contained in a shaft 186 of the exoscope 180 . A head member 190 is provided on the distal end 188 of the shaft 186 .
As can be recognized in particular from the section view in FIG. 18 , the distal end of the lens 182 ends in this head member 190 .
A single illumination unit 192 is contained in the head member 190 .
Its radiating direction 193 likewise runs at an angle of approximately 90 degrees to the longitudinal axis 187 of the shaft 186 , and this longitudinal axis 187 also extends in the direction of the longitudinal axis of the lens 182 .
Contained in the shaft 186 are light conductors 194 that comprise a curvature 195 in the head member 190 so that they radiate illuminating light in the radiating direction 193 .
On the proximal side the base member 184 comprises a housing 198 , from which a light conductor connection 196 protrudes laterally. This light conductor connection 196 is connected by a cable 200 with a light source.
Here too a focusing device 202 is present inside the head member 190 .
Said device serves once again not to configure the individual light conductors 194 but rather to guide the illuminating light homogeneously to the surgical site.
It can be recognized from the sectional depiction in FIG. 18 that the image input position of the lens 182 and the light outlet position of the illuminating unit 192 are situated successively in a row in the direction of the longitudinal axis 87 of the exoscope 180 .
They can also be situated alongside one another, viewed in the direction of the longitudinal axis 187 .
The light beam of the illuminating unit 192 is adjusted by the producer in such a way that at the customary working distances, that is, primarily in the range between 20 and 60 cm, there is homogeneous illumination; that is, the viewing beam of the lens intersects accordingly the illuminating beam of the illuminating light.
A sixth embodiment of an inventive exoscope, shown in FIGS. 19 through 22 , is designated in its entirety with reference number 210 .
The exoscope 210 comprises a lens 212 that as previously described makes possible a shaft 213 and a window 211 for a 90 degree view from the longitudinal axis of the shaft 213 .
The base member of the exoscope 210 consists of a first module 214 and a second module 222 .
The first module 214 comprises an elongated shaft 216 , which comprises on its proximal end a light conductor connection 218 bent at an angle.
On the distal end the shaft 216 comprises a widened head member 219 in which an illuminating unit 220 is contained.
Here again, as previously described, light conductors 221 in the shaft 216 are conducted to the illuminating unit 220 .
The second module 222 likewise comprises a shaft 224 , which has on its proximal side an angled light conductor connection 226 . Present on the distal end is a widened head member 227 in which an illuminating unit 228 is contained.
Here again light conductors are conducted by the light conductor connection 226 through the shaft 224 to the illuminating unit 228 .
FIG. 20 shows how the three component elements, namely the lens 212 , the first module 214 , and a second module 222 , are combined to form the exoscope 210 as an end product.
It can be seen in connection with FIG. 19 that the configuration of the head members 219 , of the first module 214 , and of the head member 227 of the second module 222 are configured in such a way that they can be fused with one another and thereby consequently the two illuminating units 220 and 228 are positioned in a row one after the other, viewed in the longitudinal axis of the shafts 216 and 224 .
For this purpose there is present in the head member 227 a corresponding recess, not presented in further detail here, into which the head member 219 can be fittingly inserted laterally, corresponding to the transition from FIG. 19 to FIG. 20 .
It can be recognized from the sectional depiction in FIG. 21 that the shaft 213 of the lens 212 , the shaft 216 of the first module 214 , and the shaft 224 of the second module 222 are shaped in such a way that the two shafts 224 and 216 can be closely fitted together on an outer side of the shaft 213 .
The combined structure of the three shafts 213 , 216 , and 224 is held together by a fastening that encloses them in the shape of a clamp.
The clamp 230 comprises a narrowing 231 for better spreading on the outside.
It can be recognized from FIG. 20 that the distal end of the shaft 213 of the lens 212 comes to rest in a vacant area in the head member 219 , in such a way that the window 211 in a row and comes to rest, viewed from the proximal toward the distal side, before the row of illuminating units 220 , 228 .
In practical application, the exoscope 210 can be used, completely assembled, in the condition shown in FIG. 20 .
It is also possible, as shown in FIG. 22 , to use the exoscope 210 with components separated from one another.
FIG. 22 indicates a surgical area that is to be observed and illuminated by the exoscope 210 .
FIG. 22 indicates that the three components, namely the lens 212 , the first module 214 , and the second module 222 , are positioned approximately in star form, each displaced by 120 degrees, around the surgical area 232 . Because both the first module 214 and the second module 222 are provided with their own light conductors 221 , 229 , and the latter are also conducted to a corresponding illuminating source, the two modules 214 and 222 can be used completely independently of one another but they can also both be employed contiguous with one another.
The star-shaped arrangement is of course only an example; these individual instruments can also be grouped or positioned in distribution at different angles to one another.
The intention here is merely to demonstrate the flexibility that exists for the person conducting the operation to achieve optimal observation and equally favorable illumination in a particular surgical area 232 .
The embodiment indicates that each of the modules 214 , 222 comprises only one illuminating unit.
It is also possible to construct embodiments in which two or more illuminating units exist. This modular structure not only expands the range of applications but also allows a simple cleaning and sterilization after a use. By releasing the clamp 230 , the individual component elements, namely the lens 212 , first module 214 , and second module 222 , can then be separately cleaned, sterilized, and further treated in preparation for another use.
FIG. 23 shows a seventh embodiment of an inventive exoscope, which is designated in its entirety with reference number 240 .
The exoscope 240 is also of modular construction.
The exoscope 240 comprises a lens 242 , which has an elongated shaft 243 as has been repeatedly described heretofore.
Here too a window 245 is present that allows a 90 degree view from the longitudinal axis of the shaft 243 outward.
The lens 242 is mounted on a base member 244 , which itself in turn consists of a first module 246 and a second module 252 .
The first module 246 here comprises once again a shaft 248 , which comprises a head member 249 positioned laterally with respect to its longitudinal axis, with an illuminating unit 250 .
The second module 252 likewise comprises an elongated shaft 254 and is continued likewise in a head member 255 pointing laterally in the same direction as the head member 249 , which includes an illuminating unit 256 .
The two head members 249 and 255 are contiguous with one another via a straight shared surface. Here too, light conductors, not shown in greater detail, are conducted inside the shafts 248 and 254 to the illuminating units 250 and 256 .
This combined structure of a lens 242 , first module 246 , and second module 252 can be held together, as previously described, by a fastening unit such as a clamp. In this embodiment it is also possible to clip the two modules 246 and 252 to one another or to fasten them together. Thus it is possible to handle the two modules as a base member 244 . The lens 242 can be removed from the base member 244 and inserted at another favorable position in the surgical area.
A particular advantage of this configuration with illuminating units 250 and 256 pointed laterally outwards in the same direction from the longitudinal axis of the shafts, is that it becomes possible to work unhindered with tools on the opposite side, that is, on the left side in the depiction in FIG. 23 .
A diameter 258 of the shaft 243 of the lens 242 measures approximately 7.5 mm.
The width 260 of the assembled head members 249 and 255 measures about 20 mm. The height 262 of the assembled head members 249 and 255 measures about 25 mm.
It can be seen from this that a markedly widened head member is present in comparison with the shaft or shafts. Nevertheless there is a relatively small, compact configuration of the exoscope 240 in the distal end area.
The structure as shown in FIG. 23 can be arranged horizontally in a lateral configuration to the surgical field; it can be used as such a compact combined structure 240 , as a composite of the two module parts 246 and 252 with separate lens 242 , or as described before in connection with the exoscope 210 , also in the form of three individual components, namely lens 242 , first module 246 , and second module 252 .
Although the invention has been described with reference to a particular arrangement of parts, features and the like, these are not intended to exhaust all possible arrangements or features, and indeed many other modifications and variations will be ascertainable to those of skill in the art. | An exoscope serves for observing and illuminating an object field on a patient from a position set apart from the patient's body. A lens system serves to observe the object field and an illumination serves to illuminate the object field. A distance between the lens system and the object field can be modified by a bracket. A shaft comprises on its distal end a head member that is widened in comparison to it, so that the illumination reaches into the distal-side head member. Positioned in the head member is at least one radiating illumination unit whose radiant characteristic can be adjusted in such a way that the object field can be illuminated homogeneously at all possible distances from the lens system. Supply lines for the at least one illuminating unit are positioned in the shaft. | 0 |
RELATED APPLICATION DATA
[0001] This application is a continuation-in-part of U.S. application Ser. No. 10/381,025, which is a U.S. National Phase application of International Application No. PCT/US01/29313, filed Sep. 19, 2001, incorporated by reference herein.
FIELD OF INVENTION
[0002] The invention generally relates to the field of carpet and floor covering, specifically to the area of self contained flooring systems.
BACKGROUND OF THE INVENTION
[0003] Floor covering has included a vast array of materials such as ceramic tile, wood, carpet, carpet tile and other materials. Equally as numerous have been the methods for installing and securing flooring, either permanently or temporarily, to subfloors. Traditionally, among other approaches, flooring systems have used surrounding walls as a method of containing and securing the flooring material. However, this method provides very little flexibility to the installer of the flooring system. Using existing walls as lateral support for flooring materials requires that the installer invest substantial time and labor to fit the flooring materials to the existing subfloor. Accordingly, a need exists for a method or system that allows floor tiles to be contained and laterally supported by a means other than the existing walls of the structure.
SUMMARY OF THE INVENTION
[0004] This invention is a self contained kit or a group of components from which a purchaser can assemble an area floor covering. In one embodiment, a four-sided modular frame surrounds modular units of carpet or carpet tile bounded by the frame, which also provides transition from the carpet to the floor on which the assembly lies. Frame members may be attached to the modular units and to one another. The frame members may be made of plastic, wood, metal, ceramic, marble, or other suitable materials.
[0005] One feature of this invention is a system having components salable through retail outlets for producing an area floor covering.
[0006] Another feature of this invention is a system and method for containing replaceable wear surfaces without reliance on interior walls of a room for lateral support.
[0007] Yet another feature of this invention is an efficient method of installing replaceable wear surfaces in any room with a minimal investment of time and labor.
[0008] Another feature of this invention is an area floor covering having an exterior frame that is stable and easy to assemble.
[0009] An aspect of this invention provides an area floor covering, comprising a plurality of replaceable wear surfaces having edges, and a plurality of connectable edge segments adapted to bound the plurality of replaceable wear surfaces when connected and comprising a flap having attachment material for attaching one of the replaceable wear surfaces.
[0010] Another aspect of this invention provides a framing system for an area floor covering, the framing system comprising a plurality of connectable frame segments, each segment comprising: a flap comprising adhesive for attaching a replaceable wear surface; an aperture adapted to receive a connector; and a connector retainer.
[0011] Another aspect of this invention provides an area floor covering comprising a plurality of carpet tiles and a frame adapted to bound the plurality of carpet tiles, the frame comprising: at least one connector; at least two edge segments, each segment comprising a flap comprising adhesive for attaching a replaceable wear surface, and an aperture adapted to receive the connector; and at least one a connector retainer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a top plan view of an area rug of this invention.
[0013] FIG. 2 is a side elevation view of the rug of FIG. 1 .
[0014] FIG. 3 is a cross-sectional view of a segment and replaceable wear surface of this invention.
[0015] FIG. 4 is a perspective view of a portion of the exterior frame of FIG. 1 .
[0016] FIG. 5 is an end view in cross-section of a segment of FIG. 1 .
[0017] FIG. 6 is a plan view of the bottom of the connection between two segments, without a retainer.
[0018] FIG. 7 is a perspective view of a collaboration of pieces for forming an area rug.
DETAILED DESCRIPTION OF THE INVENTION
[0019] FIG. 1 illustrates an area rug flooring system 10 of this invention. The flooring system 10 includes an exterior base 12 and multiple replaceable wear surfaces 14 . The replaceable wear surfaces 14 maybe carpet tiles or hard surface modules composed of materials such as, but not limited to hardwoods or ceramics.
[0020] In one embodiment, exterior frame 12 includes multiple segments 16 sized to receive replaceable wear surfaces 14 . The segments 16 typically are joined at a 90° angle to form a square or rectangular base 12 around the area rug 10 . Alternatively, segments 16 may be joined at other angles to form various shapes to suit the needs of the layout of the desired design. In the embodiment shown, the segments 16 include linear sides 18 and corners 20 . Corners 20 and linear sides 18 are joined to form a rectangular exterior frame 12 . However, the exterior frame 12 may be comprised of any number of segments 16 in any number of shapes, including triangular, circular, and any shape in between. The replaceable wear surfaces 14 may be assembled in various combinations and patterns to suit the needs and tastes of the consumer.
[0021] FIG. 2 is a side elevation view of the system 10 . The exterior frame 12 can be constructed of a variety of materials including plastics, wood, rubber, metals, ceramics, marble and other resilient and workable materials. Extruded plastic or aluminum profiles are particularly desirable for use as exterior frame 12 .
[0022] FIG. 3 is a cross-sectional view showing a replaceable wear surface 14 disposed within the exterior frame 12 . The segment 16 can have a thickness equal to or approximately equal to the thickness of the replaceable wear surface 14 . However, segment 16 could also have a thickness less than or more than the thickness of replaceable wear surface 14 .
[0023] As shown in FIG. 3 , frame 12 includes an exterior surface 17 , which may be formed from a hard plastic, and a flap 19 , which may be formed from a soft plastic. Exterior surface 17 also includes contact surface 21 , which may be formed from soft plastic, which provides non-skid properties to the frame member. Segments 16 and corners 20 may be co-extruded during manufacture. Upper surface 23 of flap 19 includes an adhesive 25 , which adheres to a replaceable wear surface 14 . Adhesive 25 may be a peel and stick adhesive, or any other adhesive suitable for attaching a replaceable wear surface. Segments 16 are sized to correspond to the size of a modular carpet tile, or may be designed in any suitable size or shape.
[0024] Segments 16 may be joined in a number of ways including adhesives, snap fittings, sonic welding, splines, nails, screws, or other means of attachment. In one embodiment, as shown in FIGS. 5 and 6 , the segments 16 include an aperture on the underside of the segment 16 and spaced from an end of the segment 16 . The aperture is adapted to receive end 28 of a connector 30 . A second end 28 of a connector 30 is received in an aperture in a second segment 16 . Tensioner 32 extends between ends 28 of connector 30 and is received in channel 34 on the underside of the segment. Retainer 36 having recess 38 snaps in place over connector 30 , securing the position of the components. Lip 40 of retainer 36 joins with ridge 42 of segment 16 and the opposite edge 44 of retainer 36 fits over protrusion 46 of segment 16 so that retainer 36 locks in place over each channel 34 of each segment 16 . Retainer 36 thus provides torsional stability to the union of the two segments 16 . In this manner, connector 30 and retainer 36 join two segments 16 .
[0025] The components of flooring system 10 may be sold unassembled so that the purchaser may assemble the exterior base 12 by joining segments 16 and corners 20 and positioning replaceable wear surfaces 14 within exterior base 12 in an arrangement chosen by the purchaser.
[0026] The system described above can be marketed and sold as a kit. FIG. 7 illustrates various components that may be included in various quantities. For instance, the system can be contained within a container, such as a pasteboard or other box. Alternatively, the system can be sold as individual components so that a consumer can select the pieces, such as segments 16 , and replaceable wear surfaces 14 . Further, the segments may by offered in various thickness, lengths, colors and designs. The replaceable wear surfaces 14 may also be offered in various sizes, colors and designs.
[0027] An advantage of this invention is that it provides systems and methods for installing free lay replaceable wear surfaces with a minimal investment of time and labor.
[0028] Another advantage of this invention is that it provides systems and methods for containing many types of hard and soft replaceable wear surfaces without the need for lateral support or containment typically provided by interior wall surfaces.
[0029] Yet another advantage of this invention is that it provides systems and methods for a flooring structure where the surface may be easily replaced.
[0030] Still another advantage of this invention is that modules of the replaceable wear surface may be assembled in multiple configurations in order to obtain multiple designs with the same components.
[0031] An additional advantage of this invention is that the rug may be installed in oddly shaped rooms with a minimal investment of time and labor.
[0032] While various embodiments of this invention have been described above, these descriptions are given for purposes of illustration and explanation. Variations, changes, modifications and departures from the systems and methods disclosed above may be adopted without departure from the spirit and scope of this invention. | A flooring system including a modular frame surrounding modular floor covering units. Frame members attach easily to one another, providing stability to the flooring system and ease of installation. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates a program-controlled unit and a method for operating that program-controlled unit.
BACKGROUND INFORMATION
[0002] Program-controlled units are embodied, for example, as microprocessors, microcontrollers, signal processors, or the like. A microcontroller has a microcontroller core, one or more memories (program memory, data memory, etc.), peripheral components (oscillator, I/O ports, timer, A/D converter, D/A converter, communications interfaces) and an interrupt system, which are together integrated on a chip and interconnected via one or more buses (internal, external data/address bus). The construction and manner of operation of a program-controlled unit of this kind are widely known and therefore need not be discussed further in detail.
[0003] In the context of a modular microcontroller concept, the microcontroller core is the on-chip integrated central control unit (CPU). It substantially contains a more or less complex control unit, several registers (data register, address register), a bus control unit, and a calculation unit (arithmetic logic unit=ALU) which performs the actual data-processing function. An ALU calculation unit of this kind can usually perform only simple elementary operations involving a maximum of two input data (operands). These operands, as well as the results of the calculation, can be accommodated before and after processing in register or memory locations provided expressly for them. Errors can occur during processing of the operands, however, and can have a disadvantageous effect on the result. Such an error can result from the fact that at least one operand injected into the input side of the ALU becomes corrupted. This can happen, for example, because (the) potential representing the particular input datum is higher or lower than provided for. If this change in charge is great enough, a potential representing one logic state can be changed into a potential representing a different logic state. For example, a potential representing a logical “1” can be changed into a potential representing a logical “0” and vice versa, but this significantly corrupts the result.
[0004] With the continuing development of semiconductor process engineering toward smaller dimensions and lower operating voltages, the probability of the above-described types of errors is increasing. For this reason, modern microprocessor systems are equipped with a system for error detection or error recovery, with which system an error that occurs can be identified and displayed (failure identification) and, depending on the functionality of the system, actions can be taken in the event an error occurs. An error correction system of this kind can be provided, for example, by way of an ECC (error checking and correction) system that contributes to the protection of important data. In order to be able to react to errors, modern microcontroller systems are usually equipped with an error detection system based on redundant system functionality. System redundancy can be implemented, for example, by multiple time-offset calculation (temporal redundancy) or by way of additional circuits (hardware redundancy). In the former case, in which an application program is executed several times in chronological succession, sporadic or statistical errors that occur during operation can be detected. This type of redundancy, however, allows only error detection and a limited fail-safe functionality, which moreover is also very time-consuming and thus impairs the performance of the entire system. Error recovery is not possible in this case.
[0005] For this reason, error detection systems based on hardware redundancy are predominantly used; in these, the redundant hardware (i.e. present in duplicate) executes the application program in parallel. Published international patent application WO 01/46806 entitled “Firmware Mechanism for Correcting Soft Errors,” which corresponds to published German Patent DE 100 85 324, describes a computer system that has hardware-redundant error detection. The computer system described in WO 01/46806 has two microprocessor cores operable independently of one another, and a comparison unit downstream from the two cores. In a first operating mode (normal mode), instructions and data can be processed in the two cores independently of one another. In a second, so-called lock-step operating mode (test mode), the two cores are operated redundantly, i.e. the same instructions are processed in both cores. The results from the cores operated in redundant mode are compared with one another in the comparison unit in accordance with an error handling routine, and an error signal is generated if they do not agree. This allows the register contents of the cores to be saved. The status of the microprocessor prior to occurrence of the error event can be restored from the data saved in this fashion.
[0006] A disadvantage of the approach described in WO 01/46806 is the additional outlay necessary in order to make the redundant system available, especially since in this instance the entire core is provided in duplicate. In particular with very complex microcontrollers that consequently have a complex control unit and a complex bus control unit, the additional chip area required for redundancy is very large. In the case of chip-area-critical microcontroller systems, provision of these chip-area-consuming units is counterproductive, and is becoming increasingly unacceptable to users. For this reason alone, a demand therefore exists for differentiation on the market, as compared with substantially functionally identical competing products, by way of a decrease in chip area and thus a reduction in product costs. This represents a considerable competitive advantage.
[0007] With the system described in WO 01/46806, it is furthermore impossible to perform error qualification, so that no determination can be made as to where the error actually occurred. Only error detection takes place. An error can, however, occur at various points in the system; for example, an error can occur on a bus line or because of an erroneous operation within a calculation unit or a comparison unit. A need therefore exists for error qualification.
SUMMARY
[0008] The program-controlled unit according to the present invention and the method according to the present invention have the advantage, as compared with the conventional approaches, of making available simplified error correction that is optimized especially in terms of chip area requirement.
[0009] The present invention is based on the recognition that the entire microcontroller core need not be redundant for error recognition. It is instead entirely sufficient if only the execution unit, in which the calculation operations are ultimately performed, is redundant. This type of program-controlled unit with error detection thus makes do with very much less chip area compared with the aforementioned known system, since the provision of a duplicate control unit, bus control unit and registers, which occupy the largest chip area within a microcontroller core, can be dispensed with.
[0010] The present invention thus provides to duplicate only the execution unit of the microcontroller core. Fully functional error detection is thus possible, the remaining components of a microcontroller core, e.g. the control unit and bus control unit, being protected by other error detection mechanisms based on error detection or error correction codes. It is thus possible to provide a program-controlled unit, with an error detection device, that makes do with a much smaller chip area than conventional program-controlled units that have, for error detection, a so-called dual-core microcontroller equipped with two microcontroller cores. The chip area of the program-controlled unit according to the present invention, and of its error correction device, is larger than the chip area of so-called single-core program-controlled units, i.e. those that have only one microcontroller core and thus no error detection device. The chip area of the program-controlled unit according to the present invention and its error detection device is, however, significantly reduced as compared with dual-core microcontrollers.
[0011] The particular advantage of the method and the system according to the present invention is also that an error can be detected within one clock cycle, and corresponding corrective measures can thus be initiated very quickly. The performance of the system as a whole is thus almost unimpaired.
[0012] A further advantage of the present invention lies in the fact that in addition to detection of an error, an error qualification is also possible, i.e. the error location within the program-controlled unit at which the error occurred can be determined.
[0013] The program-controlled unit according to the present invention has a first operating mode, hereinafter referred to as normal mode, and a second operating mode, hereinafter referred to as test mode. The program-controlled unit has a single microcontroller core that, however, is equipped with two execution units. “Execution unit” is to be understood as, for example, an arithmetic logic unit (ALU) in which the actual data processing functions are performed. The execution unit is often also referred to as the arithmetic unit or computation unit. In normal mode the two execution units can, but need not necessarily, process instructions in parallel. In test mode, error detection occurs. In test mode, identical instructions are injected in parallel into both execution units. The existence of an error can thus be detected from a comparison of the two results.
[0014] Provided for this purpose is an error detection device that, in test mode, performs an error detection and/or error correction. Correction of an error discovered in the execution unit is accomplished, in accordance with an error handling routine (error correction method), by repeating a corresponding instruction. Depending on the nature of the core, shadow registers for the input register are necessary for this purpose.
[0015] For error-correction purposes, the error correction device has a coder with which data are equipped with an error detection code and/or an error correction code. Result data, which can be picked off at the output side of the execution units subsequent to calculation, are equipped with the corresponding error detection code or error correction code.
[0016] Data injected into the input side of the execution unit are typically not equipped with an error detection code and/or error correction code. All that is done here is to create a checksum of the injected data. This checksum is compared with the checksum stored in the registers, and in the event of a corruption the data are corrected and injected again into the execution unit, but without a checksum.
[0017] In a first example embodiment, the error detection device has a first comparison unit that is placed downstream from the two execution units on the output side. This comparison unit compares the result data calculated by the computation units, or the data's error correction coding, in accordance with an error handling routine. In the event an error is detected, i.e. in the event the result data or error correction codings do not agree, this is recognized as an error and an error signal is outputted.
[0018] In a further example embodiment, the error detection device has a second comparison unit that is placed upstream from at least one of the execution units on the input side. This comparison unit compares the operands delivered to a respective operating unit, or their error correction coding, in accordance with an error handling routine. If an error is present, i.e. in the event of a discrepancy in the input data or error correction coding compared with one another in the comparison unit, this is interpreted as an error and an error signal is then outputted.
[0019] In a further example embodiment, a shared data register is provided that, in test mode, is associated with both execution units. Data that are to be conveyed, for example, via a bus to the execution units can be stored in this shared data register.
[0020] In a further example embodiment, a shadow register may be provided in which the input data most recently conveyed to the respective execution units in test mode prior to calculation are stored. In a very simple embodiment, this type of shadow register can be embodied as a simple FIFO (first in first out). This FIFO is advanced, and therefore can be overwritten again, only when the comparison within the comparison units indicates that no error is present.
[0021] Advantageously provided for this is a control device that is coupled on the input side to the error detection device and on the output side to the shadow register. If the error detection device recognizes that no error is present, the control device generates an enable signal that enables the shadow register to be overwritten again.
[0022] The program-controlled unit according to the present invention may be implemented, for example, as a microcontroller, microprocessor, signal processor, or a control unit configured in other suitable fashion.
[0023] In a very advantageous method according to the present invention, the input data, or the calculated result data or their error codings, are compared with one another. If this comparison indicates that the data or codes do not correspond to one another, this is then interpreted as an error and an error signal is generated.
[0024] In an advantageous example embodiment, a separate error signal is outputted for each of these errors, so that a localization of the error location is possible based on the error signal. It is thereby possible to distinguish various types of error from one another. In this way, for example, an error occurring as a result of incorrect coding can be distinguished from an error caused by incorrect data injected via the bus lines or one generated within the computation unit. As a result, in very advantageous fashion, error quantification is also possible in addition to error qualification.
[0025] In a particularly advantageous example embodiment, the operands injected into the computation units on the input side are first conveyed to both execution units. Only then is a checksum (e.g. parity, CRC, ECC) created from these input data and conveyed to the input-side comparators. The performance of the data processing system is therefore not appreciably impaired by the input-side error correction.
[0026] In the method according to the present invention, the stored input data from the last calculation are not overwritten until a comparison within an error detection device indicates that no error is present. This ensures that the data originally injected, and their codes, are not lost even in the event of an incorrect calculation in one of the execution units, or in the event of a coding error.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 shows a first functional diagram for illustrating an example embodiment of the program-controlled unit according to the present invention and its operation.
[0028] FIG. 2 shows a second functional diagram for illustrating another example embodiment of the program-controlled unit according to the present invention and its operation.
DETAILED DESCRIPTION
[0029] In FIGS. 1 and 2 , identical or identically functioning elements have been labeled with identical reference characters unless otherwise indicated. For better clarity, the program-controlled unit according to the present invention, as well as its components such as the microcontroller core (CPU), memory units, peripheral units, etc., are not depicted in FIGS. 1 and 2 .
[0030] In FIGS. 1 and 2 , reference characters 1 and 2 respectively designate arithmetic logic units (ALUs). A respective ALU 1 , 2 has two inputs and one output. In a test mode, the operands provided for execution can be injected directly (not depicted) from bus 3 into the inputs of ALUs 1 , 2 , or can previously be stored in an operand register 8 , 9 provided expressly therefor. These operand registers 8 , 9 are coupled directly to data bus 3 . The two ALUs 1 , 2 are therefore supplied from the same operand registers 8 , 9 . Provision can additionally be made for the respective operands already to be provided, via the bus, with an ECC coding which are stored in register regions 8 ′, 9 ′.
[0031] In the context of injection of the respective operands into ALUs 1 , 2 , particular attention must be paid to correct data input. For example, if the same incorrect operands are injected into both ALUs 1 , 2 , an error at the output of ALUs 1 , 2 is not detectable. It must therefore be ensured that at least one of ALUs 1 , 2 receives a correct data input value, or even that the two ALUs 1 , 2 receive different but incorrect data input values. This is ensured by the fact that a checksum (e.g. parity, CRC, ECC) is created from at least one input value of an ALU 1 , 2 . In a comparison unit 5 , 6 expressly provided, ECC coding 10 ′, 11 ′ from these additional data registers 10 , 11 is compared with ECC coding 8 ′, 9 ′ from the original source register 8 , 9 . Optionally, the input data from registers 10 , 11 can also be compared (not depicted) with those from source registers 8 , 9 . If a difference is apparent in the ECC coding or in the operands, this is then interpreted as an error and an error signal is outputted.
[0032] This comparison may be accomplished during processing of the operands in ALUs 1 , 2 , so that this input-side error detection and error correction proceeds with almost no performance loss. If one of comparison units 5 , 6 detects an error, the calculation can be repeated within the next cycle. The use of a shadow register may be incorporated here so that the operands of the last calculation are always saved, in order to be quickly available again in the event of an error. Provision of a shadow register can be dispensed with, however, if the respective operand registers 10 , 11 are overwritten again only by way of an enable signal based on absence of an error. In the event of an error, comparison units 5 , 6 furnish an error signal which causes operand registers 10 , 11 not to be overwritten.
[0033] ALUs 1 , 2 each generate a result at the output side. The result data and their ECC codings made available by ALUs 1 , 2 are stored in result registers 12 , 13 , 12 ′, 13 ′. These result data and/or their codings are compared with one another in comparison unit 14 . In the event an error is not present, an enabling signal 16 is generated. This enabling signal 16 is injected into enabling device 15 , which is authorized to write the result data to a bus 4 . These result data can then be further processed via bus 4 .
[0034] Enable signal 16 can furthermore be used to release registers 8 - 11 , so that the next operands can be read out from bus 3 and processed in ALUs 1 , 2 .
[0035] With the system shown in FIG. 1 , the result is not checked. Here the result data are simply compared with one another in comparison unit 14 . Checking of the ECC codings of the result data is made possible by the system shown in FIG. 2 , in which both the result data and their ECC codings are compared with one another in comparison unit 14 .
[0036] All transient errors, permanent errors, and even runtime errors are detected with the error detection assemblage described in FIGS. 1 and 2 . Runtime errors within one ALU 1 , 2 are detected if the result arrives too late or not at all at comparison unit 12 , and a comparison is thus performed using a partial result. Because operand registers 8 , 9 , 10 , 11 with the error detection and error correction codes are saved, and because the final results are compared, the location and time of the particular error can be precisely localized. A transient fault can therefore be reacted to very quickly.
[0037] The following possibilities for error localization thus result:
If a comparison of the result data in comparison unit 14 indicates a difference, an error within one of ALUs 1 , 2 can be inferred. If a comparison of the ECC codes in one of comparison units 5 , 6 indicates a difference, an incorrect signal from bus 3 or upstream components can be inferred. If a comparison of the ECC codes in comparison unit 14 indicates a difference, incorrect coding of the result can be inferred.
[0041] Although the present invention has been described above with reference to example embodiments, it is not limited thereto but rather is modifiable in many ways and fashions known to one skilled in the art. | A program-controlled unit includes a single controller core that has a first and at least a second execution unit, which units are operable independently of one another in a first operating mode, and process the same instructions in parallel in a second operating mode. | 6 |
BACKGROUND OF THE INVENTION
Hydraulic brake boosters, such as disclosed in U.S. Pat. No. 3,831,491, have been proposed for general use in vehicles because of their compactness and reliability. In such brake boosters, the input force from the operator, which is modified through a ratio changer, moves a valve to allow a proportional volume of fluid under pressure to actuate the wheel brakes of the vehicle.
In order to maintain the number of components attached to the drive train of the motor of the vehicle at a minimum, it was suggested as disclosed in U.S. Pat. No. 3,838,629, that a portion of the output of the pump that supplies the power steering gear be diverted to operate the hydraulic brake booster.
In a further effort to better utilize the space available under the hood of vehicles, U.S. patent application Ser. No. 670,513 discloses a single housing for retaining both a hydraulic brake booster and a power steering gear. A flow control valve in the housing, in response to a brake actuator signal, diverts a portion of the output of the pump away from the rotary valve in the steering gear to provide the hydraulic brake booster with a power assist.
In another integrated brake and steering system, as disclosed in U.S. patent application Ser. No. 832,135, a single valve was adapted to operate in translatory and rotational modes to control the communication of pressurized fluid to a valve system and/or a steering system corresponding to independent operator brake and steering signals.
In another integrated brake and steering system, as disclosed in U.S. patent application Ser. No. 882,716, an integral control mechanism was developed having a rotary valve for regulating the communication of fluid to the steering system concentrically located in a spool valve that regulated the communication of fluid to the brake system.
Even though the known integrated brake and steering mechanisms performed in an adequate manner, because of space limitations between the steering shaft and brake pedal linkage, they have not been universally accepted for all vehicles. Thus, a steering control mechanism, as disclosed in copending U.S. patent application Ser. No. 892,051 was developed to permit an integrated brake and steering power assist mechanism to be remotely positioned with respect to the power steering shaft.
SUMMARY OF THE INVENTION
I have devised a rotary valve mechanism for use in a remotely positioned integrated brake and steering power assist mechanism that provides a steering shaft with a rotational force in response to an operator steering signal as does the integrated mechanism disclosed in copending application Ser. No. 892,051.
The power assist mechanism has a housing with a first bore therein for retaining the rotary valve and a second bore for retaining a movable piston. The first bore is connected to a source of fluid under pressure, the second bore and a reservoir for the source of fluid. The rotary valve has a first end attached to the housing and a second end that extends through the housing. A series of grooves and slots in the rotary valve controls the flow of fluid through the first bore.
A carrier member attached to the second end of the rotary valve has first and second arms that hold first and second sprockets, respectively, in contact with the chain that connects a pinion of the movable piston with a gear fixed to the steering shaft.
A steering signal applied to the steering shaft by an operator puts tension on the chain between the gear on the steering shaft and one of the first and second sprockets. The tension on the chain causes the carrier member to rotate the rotary valve and restrict the communication of fluid from the source to develop a pressure differential across the piston. When the pressure differential reaches a predetermined level, the piston moves a rack to produce a rotational torque in a pinion. Thereafter, this rotational torque is transmitted through the chain to the gear on the steering shaft to provide a power assist in the operation of the steering gear connected to the wheels of the vehicle.
It is an object of this invention to provide an integrated brake and steering system with a rotary valve that controls the development of a power assist torque to augment a manual steering signal in the operation of a steering gear connected to the wheels of a vehicle.
It is another object of this invention to provide a rotary valve in a steering mechanism with an actuator mechanism responsive to the tension in a chain through which an operational power assist is transmitted to a steering shaft. This operational power assist and a manual steering input is transmitted into a steering gear through the steering shaft which controls the movement of the wheels of a vehicle.
It is a further object of this invention to provide an integrated control for a power assist brake and steering system with a rotary valve having a pinion with slots and grooves therein for controlling the communication of fluid to a movable member through which the steering system is provided an assist in controlling the movement of the wheels of a vehicle.
These and other objects should be apparent from reading this specification and viewing the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of a control mechanism made according to the teachings of this invention in an integrated brake and steering system of a vehicle;
FIG. 2 is a sectional view of the control mechanism of FIG. 1;
FIG. 3 is a sectional view taken along line 3--3 of FIG. 2;
FIG. 4 is a view taken along line 4--4 of FIG. 2;
FIG. 5 is a sectional view of a secondary embodiment of a rotary valve arrangement for use in the control mechanism shown in FIG. 2; and
FIG. 6 is a sectional view taken along line 6--6 of FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
The integrated brake and steering systems shown in FIG. 1 has a control mechanism 10 which is connected to a hydraulic pump 12 by a supply conduit 14 and a return conduit 16.
In response to a brake input force applied to brake pedal 18 by an operator, the control mechanism 10 is operated to provide master cylinder 20 with an input force sufficient to effect a brake application of the front and rear wheel brakes 22 and 24, respectively.
In response to a steering input force applied to the steering shaft 26, the control mechanism 10 is operated to provide an additional rotative force to operate the steering gear 28 and correspondingly move or turn the wheels of the vehicle.
In more particular detail, as shown in FIG. 2, the control mechanism 10 has a housing 30 with a first bore 32, a second bore 34 and a third bore 36 located therein. The first bore 32 is connected to the supply conduit 14 by port 38, to the second bore 34 through passageways 40 and 42, see FIG. 3, and to the third bore 36 through passageway 44.
A rotary valve member 46 located in the first bore 32 regulates the communication of the fluid from port 38 to the first, second and third passageways 40, 42 and 44, respectively.
The rotary valve member 46 includes a sleeve 48 which has a series of slots 50, 52, 54 and 56 located between ribs 58, 60, 62 and 64, see FIG. 3, the first cross bore 66 which connects port 38 with cavity 68 in housing 30 adjacent bore 32, and a second cross bore 70 that connects return passage 72 with the third passageway 44. A torsion bar 76 has a first end 78 fixed to housing 30 by a pin 80 and a second end 82 fixed to the sleeve 48 by pin 84. Seals 86 and 88 which surround the torsion bar 76 prevent fluid, which flows from return passage 72 to the third passageway 44 through cross bore 70, from leaking to the surrounding environment. The torsion bar 76 normally holds the sleeve 48 in a position as illustrated in FIG. 2, such that fluid flows from port 38 through cross bore 66 to cavity 68. The volume of fluid in cavity 68 is divided with approximately one-half flowing to groove 58 and the other half flowing to groove 56 for communication to the second bore 34 through passageways 40 and 42, respectively.
A tubular member or sleeve 90 as illustrated in FIG. 3 is positioned and held in bore 34 by end caps 92 and 94 attached to projections 96 and 99, respectively, extending from housing 30. Sleeve 90 cooperates with projection 96, rib 102 and end cap 92 to establish a flow path 98 between passage 40 and radial openings 100 adjacent end cap 92, and with 99, 98, rib 104 and end cap 94 to establish a flow path 106 between passageway 42 and radial openings 108 adjacent end cap 94.
A piston 110 having a first cylindrical member 112 separated from a second cylindrical member 114 by a rock 128 is located within the sleeve 90. The first cylindrical member 112 cooperates with sleeve 90 and end cap 92 to define a first chamber 120 while cylindrical member 114 cooperates with sleeve 90 and end cap 94 to define a second chamber 122 within the housing 30. Cylindrical members 112 and 114 have bumpers 124 and 126 located thereon which engage end caps 92 and 94, respectively, and prevent the interruption of fluid communication to chambers 120, 122 from flow paths 98 and 106 during movement of the piston 110 within the sleeve 90. Seals 116 and 118 on cylindrical members 112 and 114, respectively, prevent communication of fluid between the first chamber 120 and the second chamber 122.
A pinion member 130 as shown in FIG. 2 has a shaft 131 with a first cylindrical portion 132 journalled in bearing 134 fixed in housing 30 and a second cylindrical portion 136 which extends through bearing 138 to a position external to housing 30. The pinion member 130 has a plurality of teeth 142 which mesh with teeth 144 on the rack 128 to convert linear movement of the piston 110 into rotary movement of the pinion shaft 131.
An indexing member 140 which is attached to sleeve 90 by screw 148 has a face 146 that engages surface 150 of rack 128. The indexing member 140 holds teeth 144 into engagement with teeth 142 to prevent stripping of these teeth by bowing of the rack 128 during movement of the piston 110 by the difference in fluid pressure between the first chamber 120 and the second chamber 122.
A driver gear 152, as best shown in FIG. 4, which is fixed to the end of the second cylindrical portion 136 of shaft 131 transfers rotary movement of the pinion member 130 to gear 154 fixed to the steering shaft 26 through chain 156.
A carrier member 158 which is fixed to the rotary valve 46 holds sprockets 160 and 162 taut against the chain 156 to assure that movement of gear 152 is directly transferred to gear 154 on shaft 26.
The carrier member 158 has a first arm 164 and a second arm 166 positioned against shoulder 168 on sleeve 48 by threaded stud 170. The end 172 of the first arm 164 is offset with respect to shoulder 168 in order that sprocket 160 is aligned with chain 156. Similarly end 174 is offset with respect to shoulder 168 in order to align sprocket 162 with chain 156.
Sprockets 160 and 162 are attached to arms 164 and 166, respectively by pins 176 and 178.
A tensioning member 180 as best shown in FIG. 4, FIG. 4, has a first cylindrical member 182 with a slot 184 on the end thereof and a second cylindrical member 186 with a slot 188 located on the end thereof. A projection 190 on arm 164 is located in slot 184 and a projection 192 on arm 166 is located in slot 188. A pawl wheel 194 on threaded stem 196 which is attached to cylindrical member 186 has internal threads therein. By moving pawl wheel 194 with respect to cylindrical member 186 the sprocket wheels 160 and 162 increase the tension on chain 156 as arms 164 and 166 pivot on sleeve 48. When the desired tension is achieved and slots 58 and 62 are centered with respect to port 38 and chamber 68, stud 170 is tightened to fix the position of the arms 164 and 166 with respect to the rotary valve 46 to allow fluid from the pump to freely flow from port 38 to passage 44 in the absence of a steering signal.
The fluid in passage 44 enters bore 36 through port 200 and passes through passages 202 in piston 204 before returning to the reservoir in pump 12 by conduit 16.
Flow of fluid through passage 202 is regulated by the brake control valve 206 which is fully disclosed in U.S. Pat. No. 3,967,536 is connected to push rod 208 attached to the brake pedal 18.
Control valve 206 has a poppet member 212 connected to push rod 208 through bolt 220 of a spring cage mechanism 213. Return spring 222 connected to piston 204, holds the poppet 212 away from seat 214 to allow the fluid to freely flow into chamber 218 from chamber 216. Piston 204 is attached to push rod 224 through a threaded connection 226.
MODE OF OPERATION OF THE INVENTION
When the engine in a vehicle equipped with a pump 12 is operating, a belt from the crankshaft continually rotates pulley 230 to produce a fluid flow in supply conduit 14.
The fluid in conduit 14 is presented to port 38 in the control mechanism 10 through which the brake and steering systems in the vehicle are provided with a power assist.
The fluid flows through port 38 around rib 62 along a first flow path to passage 44 and through cross bore 66 in a second flow path to passageway 44.
In the first flow path, fluid flows through either slot 52 to cross bore 70 or slot 54 for communication to return cavity 71.
In the second flow path, the fluid in cavity 68 flows around rib 58 for distribution through slot 50 to passageway 40 and slot 56 to passageway 42. With the flow of fluid from cavity 68 unrestricted, the fluid pressure in chambers 120 and 122 are equal. The entire fluid flow from cavity 68 flows through either slot 56 to return cavity 71 or slot 50 to cavity 72 for distribution to return cavity 71 through cross bore 70.
Thus, the same volume of fluid that enters port 38 is flowing in passageway 44 to the control valve 206. The fluid enters bore 36 by flowing into chamber 216 through port 200. Piston 204 has a series of passages 205 through which the fluid is communicated to passage 202 to chamber 218 for return to the reservoir by conduit 16.
When the operator desires to effect a brake application, an input force applied to brake pedal 18 is transmitted through push rod 208 to the control valve 206. Movement of the control valve restricts the flow of fluid through passage 202 by moving poppet 212 toward seat 214 causing a pressure differential to occur between chambers 216 and 218. This pressure differential acts on piston face 215 and moves the piston 204 toward chamber 218. When piston 204 moves toward chamber 218, a force is developed and transmitted through push rod 224 to operate the master cylinder 20 and provide the front and rear wheel brakes 22 and 24 with pressurized fluid to effect a brake application.
When sleeve 48 is rotated, the flow communication from port 38 through cavity 68 is restricted to one of the passages 40 and 42 while the other of the passages 40 and 42 is opened to receive the full pump pressure. However, the passage through which the flow from cavity 68 is restricted, is proportionally opened to passage 44 going to the reservoir.
The full pump pressure, is transmitted through one of passages 40 and 42 depending on the direction desired to turn, 42 for left and 40 for right, to the corresponding pressure chamber 120 or 122. Since the pump pressure is on one side of the piston 110 and the other side is communicated to the reservoir, a pressure differential is created. This pressure differential acts piston 110 and moves the piston 110 toward the chamber in free communication with the reservoir through passage 44. When piston 110 moves, teeth 144 on rack 128 engage teeth 142 and rotate pinion 130. Rotation of pinion 130 causes gear 152 to rotate and provide chain 156 with an operational force. This operational force is transmitted through chain 156 to gear 154 to provide shaft 26 with a power assist in operating steering gear 28 that turns the wheels of the vehicle.
Assume that the piston 110 and the sleeve 48 are each in neutral positions relative to the housing 30, as shown in FIG. 3. With sleeve 48 and piston 110 in this neutral position, the fluid pressure in chambers 120, 122 is balanced. Should the operator desire to make a change in the direction the vehicle is traveling, a steering input is applied by rotating steering shaft 26 and gear 154 through wheel 25. Since gear 152 is initially stationary, the rotation of gear 154 produces tension in one portion of chain 156 and slack in the other portion. For example, if gear 154, when viewed as in FIG. 4, is rotated counterclockwise, this rotation produces tension in the portion of chain 156 which engages sprocket 162 and arm 166 while producing slack in the portion of chain 156 which engages sprocket 160 and arm 164. This tension acts on arm 166 to cause counterclockwise rotation of stud 170 and thus, sleeve 48, to an angularly displaced position relative to housing 30, against the resilient tension of torsion bar 76.
It should be noted that the tension in chain 156 does not merely produce a force which acts on arm 166 in a direction parallel to chain 156 since sprocket 162 would freely rotate in response to such a force without arm 166 pivoting at stud 170. Instead, the tension in chain 156 produces a force which acts on arm 166 in a direction normal to the portion of chain 156 which engages sprocket 162. It is a component of this normal force which causes arms 166 and 164 and stud 170 to rotate counterclockwise even though the portion of chain 156 on gear 152 does not initially move.
The counterclockwise rotation of sleeve 48 to this angular displaced position opens passage 40 to inlet 38 while opening passage 42 to the outlet passage 44. This causes a differential pressure in chambers 120, 122 which moves piston 110 to the left to a displaced position relative to housing 30, when viewed as in FIG. 3. This movement of piston 110 provides the power assist in the steering system through the counterclockwise rotation of pinion 130 on rack 144. The counterclockwise rotation of pinion 130 produces counterclockwise rotation of gear 152, when viewed as in FIG. 4.
This counterclockwise rotation of gear 152 and chain 156 relieves the tension in the portion of chain 156 which engages sprocket 162 and arm 166. The relief of the chain tension eliminates the normal force on sprocket 162 and arm 166 which caused their initial counterclockwise rotation. Then, under the influence of torsion bar 76, arms 164, 166, stud 70 and sleeve 48 rotate clockwise back to their initial neutral position with respect to housing 30, while gears 152, 154 and chain 156 remain displaced counterclockwise from their initial positions. If sprockets 160, 162 were not allowed to rotate freely about pins 170, 178 on arms 164, 166, then this clockwise rotation of sleeve 48 in response to counterclockwise rotation of gear 152 would not be possible.
When sleeve 48 has returned to its initial neutral position with respect to housing 30, the fluid pressure in chambers 120, 122 is once again balanced. This pressure balance maintains the piston 110, gear 152, chain 156 and gear 154 in their displaced positions until the vehicle operator applies a new steering signal by rotating shaft 26 to yet another position.
For some application, the sleeve and torsion bar of the rotary valve 46 can be combined into a unitary structure 201, as shown in FIG. 5.
The unitary structure 201 has a cylindrical body with a first diameter section 202 and a smaller second diameter section 205. The first diameter section 203 which extends through the housing 30 has a shoulder 207 thereon for aligning sprockets 160 and 162 on arms 164 and 166, respectively, of the carrier member 158 with chain 156. After tensioning member 180 is adjusted by moving pawl wheel 194 to separate the sprockets 160 and 162 and thereby put the proper tension on chain 156, stud 170 is tightened to fix the carrier member 158 to cylindrical body. A pin 211 extends through the second diameter section 205 to fix the cylindrical body to housing 30 and align slots 213, 215, 217 and 219 with slots 221, 223, 225 and 227 in housing 30. A land 230 on the first diameter section 202 of the cylindrical body separates slots 221, 223, 225 and 227 from groove 232 aligned with passageway 44. The cylindrical body has an axial bore 234 that connects radial bore 236 aligned with groove 232 with a radial bore 238 aligned with slots 215 and 219.
The unitary structure 201 responds to a steering input force applied to the steering shaft as follows:
Rotation of gear 154 on the steering shaft 26 puts a portion of the chain 156 in tension between gear 154 and gear 152. The tension in the chain 156 acts on either arm 162 or arm 164 to create rotational torque on the carrier member 158 and the unitary structure 201. The rotational torque places the smaller second diameter section 205 in a rotational bending moment that opposes the steering signal. As the bending moment is placed in the smaller second diameter 205, lands 240, 242, 244, 246 restrict the flow of the fluid from port 38 to one of the first and second passageways 40 and 42 and opens the other of the first and second passageways 40 and 42 to receive the full output of pump 16. At the same time, the passageway 40 or 42 through which the communication with pump 16 has been restricted is opened to passageway 44. The full pump output is communicated to the pressurizing chamber 120 or 122 associated with the steering signal (chamber 120 for a left turn and chamber 122 for a right turn) while the other chamber is communicated to the relief passageway 44 to develop a pressure differential across piston 110. The pressure differential causes piston 110 to move and through the engagement of rack 128 with pinion 130 provide drive gear 152 with rotational torque. This rotational torque is transmitted through chain 156 to provide gear 154 with an assist in the operation of steering gear 28 connected to the wheels of the vehicle.
The rotation of driver gear 152 and the chain 156 relieves the tension on chain 156, and the resiliency of the second diameter section 205 of the cylindrical body rotates lands 240, 242, 244 and 246 back to the trim position shown in FIG. 6. In this position, the fluid flow from inlet port 38 is equally divided through slots 213, 215, 217 and 219 for distribution to passageway 44 by way of radial bore 238, axial bore 234 and radial bore 236. At the same time, the pressure differential across piston 110 is eliminated since the pressure in passages 40 and 42 and correspondingly chambers 120 and 122 are equal. This pressure balance maintains the piston 110 in this position corresponding to the rotation of steering shaft 26 until such time as a new steering signal is applied to shaft 26. | A rotary valve for use in a steering control of an integrated brake and steering system. The rotary valve has a pinion with a first end fixed to a housing and a second end to which a lever arrangement is attached. The pinion has a series of grooves located on its surface and whenever the lever arrangement is moved, the grooves control the flow of fluid to a piston. Thereafter, movement of the piston by the fluid creates a rotary torque that is supplied to a steering gear to aid in the operation of the steering system. | 8 |
FIELD OF THE INVENTION
The present invention relates to a throttle control apparatus and in particular to a throttle control apparatus in which the opening of the throttle valve is varied in response to the amount of operation of an accelerator operation mechanism.
BACKGROUND OF THE INVENTION
Conventional throttle control apparatus are disclosed in Japanese Patent Laid-open Print Nos. 58(1983)-155255 and 61(1986)-89940. In these conventional apparatus, an electric controller is associated with an accelerator operation mechanism and the amount of operation thereof is fed to the controller. From the controller, the resultant operational amount, as a signal, is fed to a motor for adjusting an opening of a throttle valve. The throttle valve is urged toward its fully closed condition by a return spring. Thus, the motor driving for adjusting the opening of the throttle valve is established against the urging force of the return spring.
However, in the conventional throttle control apparatus, when an electric failure occurs, the function of the motor ceases, resulting in the throttle valve being brought into its fully closed condition. Thus, an engine stall will occur while the engine runs, or an ignition of the engine cannot be established when the engine is about to be initiated.
SUMMARY OF THE INVENTION
It is, therefore, a primary object of the present invention to provide a throttle control apparatus without the foregoing drawback.
It is another object of the present invention to provide a throttle control apparatus which assures the prevention of an engine stall or the establishment of ignition.
In order to attain the foregoing objects, a throttle control apparatus of an accelerator operation mechanism is comprised of: a throttle shaft which fixes fixing a throttle valve of an internal combustion engine thereto and supported on a housing so as to be able to rotate; a motor; an electromagnetic clutch for connecting the throttle shaft and one of the motor and the accelerator operation mechanism; a return spring urging the throttle valve toward its fully closed position; electric control means for controlling the motor and the electromagnetic clutch in such a manner that when the motor is connected to the throttle valve the motor is so controlled as to establish a throttle opening which is in response to an operation amount of the accelerator operation mechanism, when the accelerator operation mechanism is released the motor is so controlled as to establish a constant idling of the engine, and when an electric trouble occurs, the throttle shaft is directly connected to the accelerator operation mechanism; and throttle opening adjusting means for regulating an opening of the throttle valve in such a manner that the throttle valve assumes a first position for assuring sufficient opening of the throttle valve upon ignition, after establishment of ignition, the throttle valve is permitted to be rotatable between the first position and the fully closed position, and assumes a second position locating the first position and the fully closed position upon an electric failure.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present invention will be more apparent and more readily appreciated from the following detailed description of a preferred exemplary embodiment of the present invention, taken in connection with the accompanying drawings, in which;
FIG. 1 is a perspective view of an embodiment of a throttle control apparatus according to the present invention;
FIG. 2 is a cross-sectional view of a portion around an electromagnetic clutch of a throttle control apparatus shown in FIG. 1;
FIG. 3 is an exploded perspective view of a portion around an electromagnetic clutch of a throttle control apparatus shown in FIG. 1; and
FIG. 4 is a cross-sectional view of a throttle opening adjusting device of a throttle control apparatus shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.
Referring first to FIGS. 1 through 3, a throttle valve 11 is disposed in a housing 1 which forms or constitutes an intake air passage of an internal combustion engine (not shown). The throttle valve 11 is fixed to a throttle shaft 12 which is rotatably supported on the housing 1. One end of the throttle shaft 12 extends from a side of the housing 1 to the outside. At the side of the housing 1 which extends around an extending portion 12a, a case 2 is formed in a body and a cover 3 is united or integrated with the case 2. On the other hand, at a side of the housing 1 disposed opposite to the case 2 and on which the other end of the throttle shaft 12 is supported, a cylindrical support 4 is formed on the housing 1 in a body. In the support 4, a throttle opening adjusting device 170 which will be detailed later and a throttle sensor 13 are provided.
The throttle sensor 13 is connected at the top end of the throttle shaft 12. This throttle sensor 13 transforms rotational displacements into electric signals. The throttle sensor 13 is expected to feed the electric signals to a controller 100 in response to the amount of opening of the throttle valve 11. The controller 100 is in the form of a CPU or a micro-processor. Furthermore, the throttle sensor 13 is also expected to feed a signal indicating the opening and closing condition of the throttle valve 11.
An electromagnetic coil 20 is fixed to the side of the housing 1 so as to surround a base portion 12a of the throttle shaft 12. The electromagnetic coil 20 is provided with a yoke 21 which is made of a magnetic substance and a bobbin 22 which is made of resin as shown in FIGS. 1 and 2. The yoke 21 is provided with a cylindrical portion 21a at its center. Around this cylindrical portion 21a, a circular portion is formed on the yoke 21, and the yoke 21 and a coil 23 are disposed in the circular portion. A bottom portion of the yoke 21 is fixed to the side of the throttle shaft 12 which penetrates into the cylindrical portion 21a.
Moreover, a rotor 30 which is made of a magnetic substance is supported on the extending portion 12a of the throttle shaft 12 so as to be able to rotate. The rotor 30 is disposed in a prescribed portion which is opposite the yoke 21 and is held so as not to be able to move in the direction of the axis of the throttle shaft 12. As shown in FIG. 2, the rotor 30 is made of a sintered metal using mainly iron and has a shape comprised of a cylindrical portion 32 connected with an axial portion 31 that is supported on the throttle shaft 12 via arm portions 33. The axial portion 31 of the rotor 30 is fitted into the cylindrical portion 21a of the yoke 21 with a predetermined gap so as to overlap in the axial direction and the cylindrical portion 32a of the rotor 32 surrounds the outer side of the yoke 21. At an outer circumferential side of the cylindrical portion 32 of the rotor 30, outer teeth 34 are formed in a body. Furthermore, at a flat portion adjacent to the outer teeth, as shown in FIGS. 2 and 3, nail portions 35 which have a triangular cross-sectional shape are continuously arranged on the whole circumference. The nail portions 35 extend radially and possess a wavy form.
In addition, a clutch plate 40 which is of a disk shape is supported on the throttle shaft 12 so as to confront the rotor 30. The clutch plate 40 is able to move in the axial direction. The clutch plate 40 is made of a magnetic substance and is provided with nail portions 41 which have the same triangular cross-sectional shape as the nail portions 35 and which are formed on the whole circumference of its own flat portion opposite to the nail portions 35 so as to radially extend like the nail portions 35. The nail portions 41 can be formed by not only mechanism or electrospark machining but also can be formed by pressing. The electromagnetic coil 20, the rotor 30, and the clutch plate 40 constitute an electromagnetic clutch mechanism.
A pin 42 is fixed to a face of the clutch plate 40 which is located opposite the face having the second nail portions 41. Furthermore, at this face of the clutch plate 40, one of the ends of the sheet springs 45 which are shown by a chain line in FIG. 3 are fixed thereto by pins (not shown). On the other hand, the other ends of the sheet springs 45 are fixed to a plate holder 50 by pins (not shown). Accordingly, the clutch plate 40 is connected with the plate holder 50 via the sheer springs 45. If one of the pins for fixing the sheet springs 45 is extended and is used as the common pin 42, it is possible to reduce the number of parts.
At the top end portion of the extending portion 12a of the throttle shaft 12, the plate holder 50 is fixed thereto. The plate holder 50 is provided with an oval hole 51 which is formed at its center. On the other hand, the top end of the extending portion 12a of the throttle shaft 12 is formed so as to be the same cross-sectional shape as the hole 51 and is fitted into the hole 51. Thereby, the plate holder 50 is restrained from rotating with regard to the throttle shaft 12. The top end portion of the extending portion 12 has a length that is the same as the thickness of the plate holder 50. A bolt (or a nut) 14 is screwed down on the top end surface of the extending surface of the extending portion 12a and thereby the plate holder 50 is nipped between the bolt (or the nut) 14 and a step portion which is formed at a base portion of the top end portion of the extending portion 12a. The hole 51 and the top end portion of the extending portion 12a may have, for example, a semi-circular sectional shape and can be formed to have various shapes which restrain the plate holder 50 from rotating with regard to the throttle shaft 12.
The plate holder 50 is further provided with a hole 52 and several other holes. The hole 52 is formed at the outer edge portion of the plate holder 50 and a pin 42 is penetrated into and extends through the hole 52. The holes are formed for caulking the sheer springs 45. Thus, when the plate holder 50 is fixed to the throttle shaft 12, a top end of the pin 42 projects from the hole 52 of the plate holder 50 as shown in FIGS. 1 and 2.
Furthermore, an operation plate 60 is disposed around the pin 42 which is fixed to the clutch plate 40 so as to be opposite to the plate holder 50 at its outer edge portion. An acceleration shaft 62 is fixed to a center portion of the plate 60 and is supported by the cover 3 in a nearly parallel arrangement with the throttle shaft 12 so as to be able to rotate. The operation plate 60 is restrained from moving in the axial direction. The operation plate 60 is provided with a notch 61 which is formed at its outer edge portion so as to overlap with the pin 42. The operation plate 60 is arranged so that at least one of the radial surfaces 61a and 61b can contact the side of the pin 42 in response to the rotation of the operation plate 60 in the nonexciting condition of the electromagnetic coil 20.
The other end of the accelerator shaft 62 is connected with an accelerator plate 5 shown in FIG. 1 by a bolt or a nut, and a cable end 6a which is formed on one end of an accelerator cable 6 is engaged with an outer edge portion of the accelerator plate 5. The other end of the accelerator cable 6 is connected with an accelerator 7 in order that the operation plate 60 is rotated about an axial center of the accelerator shaft 62 in response to the depression of the accelerator 7. A well-known accelerator sensor 8 is installed on the accelerator 7. This accelerator sensor 8 feeds an indication of the degree of depression of the accelerator 7, as electric signals, to the controller 100.
A motor 90 which serves as a driving source is fixed to the cover 3 and a rotation shaft of the motor 90 is supported in parallel arrangement with the throttle shaft 12 so as to be able to rotate. A pinion gear 91 is fixed at a top end of the rotation shaft of the motor 90, and this pinion gear 91 is engaged with the outer teeth 34 of the rotor 30. In this embodiment, a stepping motor is employed as the motor 90 and is under the control of the controller 100. Other types of motors such as a DC motor can be used as the motor 90.
When the motor 90 is turned on and the pinion gear 91 is rotated, the rotor 30 having the outer teeth 34 which are engaged with the pinion gear 91 is rotated around the throttle shaft 12. In this situation, if the electromagnetic coil 20 is in its nonexciting condition, the clutch plate 40 is separated from the rotor 30 by the urging force of the sheet springs 45 and is located in the adjacent position to the plate holder 50. Namely, the clutch plate 40, the plate holder 50 and the throttle valve 11 can be freely rotated by the throttle shaft 12 regardless of the condition of the rotor 30. In this situation, the pin 42 which is fixed to the clutch plate 40 is located between both surfaces 61a and 61b of the notch 61 of the operation plate 60.
When the electromagnetic coil 20 is excited, a closed magnetic circuit is formed by the yoke 21, the rotor 30 and the clutch plate 40. Thereby, the clutch plate 40 is attracted toward the rotor 30 against the urging force of the sheet spring 45 by an electromagnetic force and the nail portions 35 of the rotor 30 and the nail portions 41 of the clutch plate 40 are engaged with each other. Namely, the rotor 30 and the clutch plate 40 assume an engaging condition and are able to rotate in a body. Thereby, the controlled variable driving operation of the motor 90 is transmitted from the pinion gear 91 to the rotor 30 via the outer teeth 34 and next is transmitted to the clutch plate 40 via the nail portions 35 and the nail portions 41. Furthermore, the controlled variable driving is transmitted from the clutch plate 40 to the plate holder 50 via the sheet springs 45 and therefore is transmitted to the throttle shaft 12 which rotates with the plate holder 50 in a body. As a result, the amount of opening of the throttle valve 12 is controlled in response to the above driving controlled variable. In this situation, since the pin 42 moves with the clutch plate 40 toward the rotor 30 and does not locate between both surfaces 61a and 61b of the notch 61 of the operation plate 60, the operation plate 60 is rotated regardless of the condition of the pin 42.
The electromagnetic coil 20 is controlled by the controller 100 to which various signals are fed from sensors (some of them are not shown) so as to be excited and non-excited in response to the driving condition of the vehicle. Furthermore, the driving of the motor 9 is controlled by the controller 100 so as to be able to obtain the amount of opening of the throttle valve 11 which is determined in response to the amount of depression of the accelerator 7, namely the accelerator operational amount and various control conditions.
In the foregoing structure, when the motor 90 is connected to the throttle valve 1, the controller 100 controls the opening of the throttle valve 1 so as to be in response to the degree of depression or the operation amount of the accelerator 7. When the accelerator 7 is released, the motor 90 is controlled by the controller 100 so as to establish a constant idling of the engine.
Referring to FIG. 4, a throttle opening adjusting device 170 includes an actuator 171 having an inner space in which a first chamber 171a and a second chamber 171b are defined by a diaphragm 177. The first chamber 171a is in fluid communication with the downstream end of the housing 1 through a conduit 13a in which a pressure transmission delay device 108 is provided in order that the electromagnetic clutch can be brought into its engaged condition prior to the actuation of the throttle opening adjusting device 170. This enables the prevention of an engine stall immediately upon initiation thereof. The second chamber 171b is kept at atmospheric pressure. In the first chamber 171a, there is disposed a first spring 172 for urging a base portion 173a of a moving member 173 toward the second chamber 171b. From the base portion 173a to which is secured the diaphragm 177, a shaft portion 173b extends. The shaft portion 173b extends outside the base portion 173a and passes through a distal end portion 174a of a plate 174. A distal end of the shaft portion 173b is secured to a regulating member 75 so as to be perpendicular thereto. The plate 174 is rotatably mounted on the throttle shaft 12. A spring 176 is disposed between the actuator 171 and the plate 174. A throttle lever 175 is secured to the throttle shaft 12. Between the housing 1 and a right end portion of throttle lever 175, there is disposed the return spring 76 so as to rotate the throttle valve 11 towards its closed condition. A left end of the throttle lever 175 is in abutment with the plate 174. The spring load of the spring 176 is greater than the spring load of the return spring 76, which results in the distal end 174a of the plate 174 being in engagement with the regulating member 75. This enables a unitary movement of the moving member 173, the regulating member 75 and the plate 174. As a whole, the plate 174 is applied with a downward force which is the sum of the load of the spring 172 and the spring 176 and is applied with an upward force which is the sum of the load of the spring 76 and the negative pressure. While the engine runs after its ignition, the regulating member 75 is engaged with an upper stopper portion 78b of a part 78 of the cylindrical support 4 and is at a position "B" which corresponds to a 2-degree opening of the throttle valve 11 as illustrated. The reason is that the sum of the load of the spring 172 and the spring 176 is overcome by the sum of the negative pressure and the load of the spring 76. Even though the electric control system encounters trouble, so long as the position of the regulating member 75 remains unchanged, an engine stall can be prevented. On the other hand, when the engine is at its ignition or before perfect explosion, no negative pressure is generated, which means that the spring 172 is expanded and the return spring 76 is overcome by the spring 176. Thereby the moving member 173, the plate 174 and the regulating member 75 are moved in the downward direction. Thus, the regulating member 75 is engaged with a lower stopper 78a of the part 78 of the cylindrical support 4 and is at a position "A" which corresponds to a 7-degree opening of the throttle valve 11 so that the minimum opening of the opening of the throttle valve for the ignition can be assured.
In operation, when ignition is established, the regulating member 75 is kept at the position "A" so that the opening of the throttle valve 11 is 7 degrees. If the perfect explosion is obtained, the value of the negative pressure in the conduit 13a exceeds a value, resulting in the diaphragm 177, the moving member 173, the plate 174 and the regulating member 75 being moved in the upward direction. Then, the regulating member 75 is transferred to the position "B" which leads to the opening of the throttle valve 11 of 2 degrees. The throttle lever 175 follows the movement of the plate 174. The resulting position of the throttle valve 11 is fixed by the motor 90 immediately upon engagement of the electromagnetic clutch.
While the engine runs, if the electric system encounters trouble, the application of the electric current to the electromagnetic coil 20 is interrupted. Thus, the rotor 30 and the clutch plate 40 are separated from each other, and the throttle valve 11 is urged toward its closed condition by the return spring 76. At this time, so long as the engine runs, the regulating member 75 is kept at the position "B" which means that the opening of the throttle valve 11 is 2 degrees. Thus, the fully closed condition of the throttle valve 11 cannot be established, which means that the stall of the engine can be prevented.
In addition, when trouble is experienced in the electric system, the pin 42 is located between both surfaces 61a and 61b of the notch 61 of the operating plate 60. The operating plate 60 is operated by the accelerator 7 and is rotated, the surface 61a is contacted with the side of the pin 42, and the clutch plate 40 and the plate holder 50 are rotated. Thus, a direct control of the throttle valve 12 can be established by the accelerator 7.
While this invention has been illustrated and described in accordance with a preferred embodiment, it is recognized that variations and changes may be made and equivalents employed herein without departing from the invention as set forth in the claims. | A throttle control apparatus includes a throttle opening adjusting device for regulating the throttle valve opening in such a manner that the throttle valve is located in a first position for assuring sufficient opening of the throttle valve upon ignition, with the throttle valve being rotatable after establishment of ignition or combustion. The throttle valve is then moved to a second position located between the first position and a fully closed position upon an electric failure. | 5 |
FIELD OF THE INVENTION
This invention relates generally to cathodic protection systems and more particularly cathodic protection systems for protecting metallic structures from seawater corrosion.
BACKGROUND OF THE INVENTION
When cathodic protection is used to protect structures positioned in a water environment, a variety of sacrificial and impressed current anode systems can be utilized. Generally, impressed current anode systems are used for applications where higher amperages are required to achieve the desired level of cathodic protection while sacrificial anode systems, usually made from zinc or aluminum, corrode to produce the electron flow that protects the steel structure from corrosion.
Anodes have a higher efficiency when positioned in the water, above the sea floor and sediment rather than buried beneath.
The term “sea floor” is used to describe the solid surface underlying a body of water such as, for example, oceans, seas, harbors, lakes, estuaries, etc.
Many methods have been described in the prior art which utilize one or more anode(s) to protect metallic underwater structures from corrosion. Anodes positioned on the sea floor are typically mounted on structures constructed from concrete, steel and or fiberglass. These structures are oftentimes referred to as “sleds”. Sleds are utilized to ensure that the anode(s) remain above the mudline or soft sediment deposited upon the sea floor. The sled design may also incorporate features including: a structural attachment for the anode and anode power cable, a mounting point for power cable(s) junction box, or ballast (mass/weight) to eliminate physical movement or overturning in high velocity current environments or during storm events, and protection from fishing equipment or objects that have been dropped from the surface.
For impressed current cathodic protection, the prior art anodes are connected to one or more cables, and because of the shape and construction of the anodes, the connection to the cables generally must be done in a factory before the anode is mounted to the sled. Typically, the concrete weight and support material must be cast before the anode assembly is shipped from the factory. The requirement to connect the cable and possibly cast the concrete increases the cost and shipping of the sled.
Similarly, for cathodic protection using sacrificial anodes, the design is based upon the surface area of the anode exposed to the water. Cables are then used to connect the sacrificial anode to the subsea structure.
One example of a marine system using sacrificial anodes for cathodic protection is U.S. Pat. No. 6,461,082. A plurality of sacrificial anodes are positioned on top of an elongated electrode carrier, such as a long pipe which is laid upon the seafloor. Each anode is attached to the pipe and the pipe is thereafter operably connected to the structure. In order to maximize the surface area of the anode exposed to the water, this invention requires an additional supporting structure such as a mud mat on the seafloor so that the pipe will not sink into the mud and cover the pipe and anodes.
Another example of a marine system using sacrificial anodes for cathodic protection is U.S. Pat. No. 7,329,336. A plurality of blocks spaced apart and connected by wire rope is used as a seafloor mat. Each block is filled with concrete and at least one of the blocks has embedded in it a sacrificial anode. The anode is embedded so that only the top surface of the anode is exposed for contact with the water. The blocks allow for the concrete to be poured at surface on-location; thus significantly reducing transportation costs associated with loading, hauling and unloading ballast filled blocks. However, because only the top surface of an anode is available for contact with water, surface area is compromised and it is necessary to include many more blocks having the embedded anode to achieve the same level of protection as an anode having substantially its entire surface area exposed to the water.
One example of a marine system using impressed current for cathodic protection is described in U.S. Patent Application Publication No. US 2012/0305386. This anode assembly includes a spherical anode, a vertical anode support structure and a weighted base which is hollow and made of a fiberglass shell. The lower end of the anode support structure is disposed within the hollow base which is thereafter filled with concrete.
Manufacturing and shipping costs for a state-of-the-art “anode sled” are very high, due to the materials employed and the required size of the sled.
Subsea corrosion protection can incorporate the use of fiberglass sled structures to support anode(s) above the seabed as manufactured by Marine Project Management, Inc., Ojai, Calif. (www.mpmi.com). Another method is to utilize a steel structure to support anodes which is basically a framework which lies on the sea floor as manufactured by Deepwater Corrosion Services, Inc., Houston, Tex. (www.stoprust.com). Both types of structures mentioned are expensive to fabricate and ship, and require a significant lead time to manufacture and deliver.
Grout bags have been used for many years for supporting underwater pipeline spans and are intended to be pumped full of cement grout once in place underwater. A typical grout bag is one provided by SEA STRUCT Pty Ltd, North Fremantle, Australia (www.sea-struct.com.au). These devices are more specifically used for supporting an underwater pipeline in areas where the pipe is suspended above the sea floor for a length which could cause the pipeline to buckle. Grout bags are structural in nature and are placed along a spanning pipeline to reduce the span length and are not related to anodes or cathodic protection.
SUMMARY OF THE INVENTION
My invention is a sled which can be assembled off-shore or nearby the drop point thereby eliminating the need to transport ballast filled sleds or use bulky pre-formed block shells long distances. In simplest terms, my sled is constructed using a bag or sack which can be filled with ballast. My sled design includes at least one stanchion or post extending upward from the sack and supports an anode; preferably integral with the anode. The sled can be used for both sacrificial anode and impressed current applications.
By using a bag structure, the sled can be fabricated on-site and then filled with ballast such as concrete. Overall manufacturing, shipping and handling costs can be reduced by up to 75% when compared to prior art sled designs.
The anode sled comprises a bag which was previously in a compacted condition such as flat, rolled or folded. The term “compacted condition” means a volume of space which is less than the volume of the bag when filled. The bag has a top surface, and a closable opening. When open, the closable opening has an aperture of sufficient size for insertion into the bag of a skeletal support structure. The closable opening can comprise a flap that can be attached on its perimeter to the adjacent bag surface using any means including, but not limited to zipper, Velcro®, stitching, etc. The bag also has at least one aperture located on the top surface for receiving through a respective post.
When disposed within the bag, the skeletal structure provides support to the ballast which fills the interior of the bag. Use of the phrase “fills the interior of the bag” includes the possibility that a de minimus amount of air may remain in the bag after the filling process. So long as a sufficient amount of ballast is present in the bag to perform its function as a sled, the bag is considered filled. Also, optionally are respective post bases having a wider diameter footprint for providing stability for each post while the bag is filled with ballast. The top portion of the post extends upward from a respective aperture located on the top surface of the bag.
Although at least one post supports the anode positioned above the bag's top surface, preferably, two posts are used for structural support.
In comparison to the use of pre-fabricated hollow blocks which can be filled with ballast, the bag of the present invention can be shipped in a compacted condition, thus taking up a fraction of the space required for blocks or other designs having pre-formed rigid outer walls. Preferably, the bag used is lightweight, tear-resistant and made of a pliable or flexible material. By way of example, the bag could be made of burlap, cloth, soft plastic or any other material one having skill in the art could use for filling with ballast. The bag can be made of any material so long as it is sufficiently durable to withstand being filled with ballast.
The bag can be manufactured in various widths, lengths and heights depending on both the anode size to support and the sea floor soil composition. By way of example, if the desired placement location has a significant soft sediment layer, a bag will be selected having a higher vertical dimension and wider horizontal dimension than a location having only a minimal layer of soft sediment. A primary concern is to utilize a sled design which will have a low center of gravity to prevent the sled from tipping over.
As described earlier, the sled incorporates a skeletal structure comprising reinforcing elements which can be assembled on-site, and positioned within the bag. Thus, the bag has a sufficient closable opening for insertion of the reinforcing elements.
For each post present, a corresponding post aperture is present on the top surface of the bag and the aperture is slightly larger than the outer circumference of the post. The composition of the post will depend on the specific anode type used as is well known to those having ordinary skill in the art.
Once the skeletal structure and the lower portions of each post are positioned within the bag via a respective aperture, the bag is filled with ballast such as concrete. Depending upon the bag design utilized, concrete may be poured into the opening prior to closure. Alternatively, there may be an additional, smaller port provided on the bag for adding ballast.
Depending upon how the anode is to be operatively connected, the proximal end of the cable may be directly connected to the anode and run outside of the sled. Alternatively, the anode may be operatively connected to the proximal end of the cable running through an opening in the bag and operatively attached to the anode prior to the sack being filled with ballast using methods well known to those skilled in the art. The cable is of a pre-determined length sufficient for the cable's distal end to be operatively connected to the metallic structure requiring cathodic protection.
Having described the parts of my sled, a typical method of assembly will now be described for a sled having two posts for supporting an anode.
The bag, anode, posts, and supporting hardware will be shipped to the location site.
The components used to form the skeletal structure can be assembled on-site. The term “on-site” means above the water surface on a platform, ship, or onshore nearby.
Depending upon how the bag is shipped to the assembly site, the bag will be unrolled or unfolded and positioned so that the bag surface having the opening faces upward.
The skeletal support structure is inserted through the closable opening into the bag.
Both posts are inserted into the bag and the bottom portion of each post passes through a respective aperture located on the top side of the bag so that the base of each post rests on the bottom surface of the bag, preferably nested in a support base. The top portion of each post extends upward and away from the bag with the anode integrally connected to both posts and parallel to the top surface of the bag.
If the cable connection is to a post section located within the bag, a hole is either provided as part of the original bag design or can be cut on location. The proximal end of the cable is then run into the bag through the hole and then operatively attached to the post before the bag is filled with ballast. The cable will be of a pre-determined length sufficient for the distal end of the cable to be operatively connected to the metallic structure requiring cathodic protection. In a preferred embodiment particularly for impressed current cathodic protection systems, the physical cable connection can then be encased in urethane or similar product to prevent water intrusion in accordance with well know procedures to those having ordinary skill in the art.
The opening is then closed and the bag filled with ballast using an inlet port provided on the bag and optionally the addition of a port for venting air while filling. In a preferred embodiment, elephant trunks are used as part of the bag design for each respective opening for the posts, cable, and the ballast inlet and venting outlets. A tying device such as tie rods or the like are utilized to prevent ballast from escaping before it can cure. Once filled with ballast, the bag is now termed a sled.
After the ballast is allowed to set, the sled can be lowered into the water and positioned as desired. The location for final position of the sled is in accordance with well-known procedures to those having ordinary skill in the art.
In its final resting position, the distal end of the cable is operably connected to the metallic structure or electrical system intended for cathodic protection by divers or remote operated vehicles using methods well known.
My method, besides being a significant savings over prior art methods, is designed to serve two primary functional purposes. First, to locate the final position of the anode above the mudline of the seafloor and second, to provide sufficient weight to serve as an anchor, thus preventing any movement of the anode during the anode's life.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of the contents of a kit for fabricating an anode sled.
FIG. 2 is an assembled anode sled according to one embodiment of the invention.
FIG. 3 illustrates the closable opening on the top surface of a bag.
FIG. 4 is the assembled skeletal structural support for the interior of the sled bag.
FIG. 5 illustrates one embodiment for connection of a cable.
FIG. 6 illustrates the structural support within the bag and cable connection
FIG. 7 illustrates an input port embodiment of the sled bag for filling with ballast.
FIG. 8 is an illustration of a first alternative embodiment where each hole has a respective elephant trunk for tie-down purposes.
FIG. 9 illustrates FIG. 8 fully assembled.
FIG. 10 is an illustration of a second alternative embodiment showing a pair of anodes supported by the sled.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The figures are provided for illustration purposes and are not necessarily to be drawn to scale.
FIG. 1 illustrates the contents of a kit K to fabricate the anode sled and operably connect the anode to an underwater structure for cathodic protection. Kit K includes a compacted bag 12 , a plurality of supports of various lengths 14 , 16 , 18 , a plurality of tie rods 20 , a plurality of rod chair stands 22 , post supports 24 , an anode 28 having integral posts 30 and 32 for attachment to a respective post support 24 , and a cable 34 for operably connecting anode 28 to an underwater metallic structure (not shown). Cable 34 can include a bend stiffener/restrictor (BSR) 60 and armor wire restraining plates 62 and 64 .
FIG. 2 shows the anode sled 10 assembled and ready for operable connection to an underwater metallic structure.
FIG. 3 generally shows how the exterior of bag 12 appears when filled. Bag 12 comprises a closeable opening O which can be closed when flap 26 is zippered to the adjacent top surface; post apertures A for receiving posts 30 and 32 ; port P for filling bag 12 with ballast and hole C for cable 34 to pass through. In a slightly modified embodiment represented by FIG. 8 , elephant trunks 50 , 52 , 54 , and 56 extend from bag 12 for port P′, post apertures A′, hole C′ and vent V′ respectively. Tie-rods 20 are used to facilitate closure and prevent ballast seepage as illustrated in FIG. 9 .
FIG. 4 illustrates the assembled skeletal structure depicted generally as 13 using the parts shown in FIG. 1 . Tie rods 20 (not shown in FIG. 4 ), can be used for securing adjoining parts to one another as illustrated in FIG. 5 . Parts 14 , 16 , 18 and 22 can be made either from a metal such as steel or any rigid non-metallic material such as fiberglass. This skeletal structure is positioned within the bag through opening O when zippered flap 26 is separated from the adjacent top surface of bag 12 as shown in FIG. 3 . Apertures A are sized to permit the lower portion of posts 30 and 32 to extend through and down into attachment with a respective post support 24 .
Post 30 has aperture L which allows cable 34 to pass through. As can best be seen in FIG. 5 , post 32 includes a lug 36 for mating to lug 37 , which is attached to the proximal end of cable 34 , using bolt 39 for operably connecting cable 34 to anode 28 .
FIG. 6 illustrates the general configuration of skeleton 13 , cable 34 and posts 30 and 32 connected with post supports 24 in bag 12 after zippered flap 26 closes opening O.
FIG. 7 illustrates port P used to pump ballast 38 into bag 12 . FIG. 10 illustrates an alternative embodiment for supporting a pair of anodes. Bag 12 ″ has 4 apertures for receiving two pair of posts 30 and 32 where each pair supports a respective anode 28 . Cable 34 can be junctioned within bag 12 ″ for operably connection to each anode 28 .
It will be understood that either impressed current or sacrificial anode systems can utilize my sled design. The figures described in this section were directed to a sacrificial anode system. The only difference in assembly of my sled design between the systems is that for impressed current cathodic protection, the physical cable connection to anode 28 at lugs 36 , 37 and bolt 39 is preferably encased in urethane or similar product to prevent water intrusion.
With my sled design described, the method of assembly is as follows:
Kit K is provided having a bag in a compacted condition, component parts for constructing a skeletal structure to be disposed within the bag, an anode integrally connected to at least one post having a lower end for insertion through a respective post aperture formed on the top surface of the bag, and a cable having a pre-determined length, a proximal end and a distal end. The cable length can be ordered ahead of time or supplied as a separate item once the required cable length is determined.
The bag is then uncompacted; meaning unrolled or unfolded to place the bag in a condition for receiving the assembled skeletal structure 13 which is inserted into the bag through the closable opening O. Next, post supports 24 are placed within the bag with posts 30 and 32 being inserted through the post holes A located on the top surface of the bag into engagement with post supports 24 . The proximal end of cable 34 having lug 37 is operatively connected to anode 28 by mating to lug 36 using bolt 39 . Armor wire restraining plates 62 and 64 are utilized near the proximal end to provide strain relief using well known methods.
In one embodiment, cable 34 can be shipped with restraining plates 62 and 64 attached to lug 37 and during the assembly process, the distal end of cable 34 would be run through aperture L and cable hole C. In another embodiment, cable 34 can be shipped with restraining plates 62 and 64 unassembled and during assembly, the proximal end of cable 34 would be run through cable hole C and aperture L and then assembled to restraining plates 62 and 64 for operable connection to anode 28 .
Once cable 34 , BSR 60 , post supports 24 and posts 30 and 32 are in position, flap 26 is zippered closed. If the bag design incorporates elephant trunks such as those shown in FIG. 8 , trunks 52 and 54 are now closed using tie rods 20 . Ballast is now pumped into the bag through port P′ and air within the bag escapes through vent V′. Once the bag is filled with ballast, tie rods 20 are used to seal about elephant trunks 50 and 56 . The ballast is allowed to cure and thereafter, the fully assembled anode sled can be lowered to a pre-determined position on the sea floor and operatively connected to an underwater structure requiring cathodic protection. | An anode sled for assembly is disclosed which is constructed using a bag or sack which can be filled on-site with ballast. The sled design includes at least one stanchion or post extending upward from the sack and supports an anode. The sled can be used for both sacrificial anode and impressed current applications. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to an optical pick-up device for input and output of information recorded in an optical record medium such as an optical disk; and an electric appliance using the optical pick-up device.
[0003] 2. Related Art
[0004] An optical pick-up device for reading out information recorded in an optical record medium that records information such as music, movie, or the like is used for various electric appliances such as a computer.
[0005] An optical pick-up device emits a laser beam to a recording surface of an optical record medium. As a laser beam scans the recording surface, information is read out sequentially by receiving a reflected light from the record medium by a detector. An optical pick-up device is known as the one that is composed of a base incorporated with discrete components such as a semiconductor laser, a prism, a mirror, an objective lens, a photoelectric conversion element, and the like. For example, refer to Unexamined Patent Publication No. 11-16197 (U.S. Pat. No. 6,246,644).
[0006] However, the conventional optical pick-up device is a high-precision processing product that is completed by assembling dozens of or hundreds of components. As mentioned above, since a plurality of components is incorporated thereto, the conventional optical pick-up device has a limitation of miniaturization. Accordingly, electric appliances installed with the conventional optical pick-up device are subject to restrictions in being miniaturized and lightweight. For example, a reproduction device of an optical record medium is often separately sold from the main body of a laptop computer which has the selling point of thin and weight-saving.
SUMMARY OF THE INVENTION
[0007] In view of the foregoing, it is an object of the present invention to provide an optical pick-up device capable of being miniaturized by reducing the number of components.
[0008] The present invention provides an optical pick-up device comprising a light-emitting device that emits a laser beam upon applying current. In the light-emitting device included in the optical pick-up device, an organic compound layer is interposed between a pair of electrodes. The organic compound layer, which is a main component, has a layer configuration for emitting a laser beam. In the layer configuration, the thickness of each layer is determined in consideration of the wavelength of laser oscillation.
[0009] As used herein, the term “organic compound layer” is a generic term used to refer to a thin film containing mainly an organic compound formed between a pair of electrodes. The organic compound layer is formed to be interposed between a pair of electrodes. The organic compound layer is composed of a plurality of layers, each of which has different properties such as carrier transportation properties or light-emitting properties. The organic compound layer is preferably formed to have a so-called resonator structure formed via a reflecting layer.
[0010] An optical pick-up device comprises: a light-emitting device capable of emitting a laser beam; a photodetector for receiving a reflected light from a record medium to convert the reflected light to an electric signal, wherein the reflected light is formed by an irradiation the laser beam from the light-emitting device to the record medium; and a signal processing circuit unit comprising a transistor, and the light-emitting device, the photodetector, and the signal processing circuit are formed over a same substrate.
[0011] An optical pick-up device comprises: a light-emitting device capable of emitting a laser beam; an optical system for condensing the laser beam emitted from the light-emitting device to irradiate a record medium, and for introducing a reflected light from the record medium to a photodetector; the photodetector for receiving the reflected light from the record medium to convert the reflected light to an electronic signal; and a signal processing circuit unit comprising a transistor, and the light-emitting device, the photodetector, and the signal processing circuit are formed over a same substrate.
[0012] An optical pick-up device comprises: an optical system for condensing a laser beam emitted from a light-emitting device to irradiate a record medium, and for introducing a reflected light from the record medium to a photodetector; and a base, the base comprises the light-emitting device capable of emitting a laser beam; the photodetector for receiving the reflected light from the record medium to convert the reflected light to an electric signal; and a signal processing circuit unit comprising a transistor, and the light-emitting device, the photodetector, and the signal processing circuit are integrally formed.
[0013] In the light-emitting device, an organic compound layer is formed between a pair of substrates. An emission spectrum of a light emitted from the organic compound layer has a plurality of emission peaks. The thickness of the organic compound layer is preferably controlled so as to form a stationary wave with respect to a specified wavelength. The organic compound layer is preferably formed to have a thickness of half of a specified wavelength or integral multiple of the half wavelength.
[0014] The light-emitting device may comprise an organic compound layer that emits light having a plurality of emission peaks. At least one of the emission peaks having a half bandwidth of at most 10 μm.
[0015] The light-emitting device used in an optical pick-up device according to the invention is realized to emit a laser beam. The light-emitting device can induce luminescence in addition to the laser beam. In order to couple out only a laser beam at a specified wavelength in order to utilize out-coupled light, an optical filter that transmits light at a specified wavelength may be used for the light-emitting device.
[0016] The number of components of the optical pick-up device can be reduced by forming integrally a light-emitting device formed by an organic compound material capable of emitting a laser beam; a photodetector; a control circuit formed by a thin film device such as a TFT; and the like over one substrate. As a result, the optical pick-up device can be miniaturized and lightweight.
[0017] These and other objects, features and advantages of the present invention will become more apparent upon reading of the following detailed description along with the accompanied drawings.
BRIEF DESCRIPTION OF THE INVENTION
[0018] FIG. 1 is an explanatory view for showing a structure of an optical pick-up device according to the present invention;
[0019] FIGS. 2A and 2B are perspective views for showing a state in which a light-emitting device, a photodetector, and a control circuit, each of which is formed over a same substrate, are formed over a same base;
[0020] FIGS. 3A to 3 C are cross-sectional views for showing a state in which a light-emitting device, a photodetector, and a control circuit are integrally formed over a same substrate;
[0021] FIG. 4 is an explanatory view for showing a configuration of a light-emitting device used for an optical pick-up device according to the invention;
[0022] FIGS. 5A and 5B are graphs for showing current density dependency, which is normalized by a maximum value of emission intensity, of an emission spectrum of light emitted from a light-emitting device having the configuration shown in FIG. 4 ; and
[0023] FIGS. 6A and 6B shows examples of electric appliances completed by an optical pick-up device according to the invention.
DESCRIPTION OF THE INVENTION
[0024] An embodiment of the present invention will be explained with reference to the drawings. According to the embodiment, a light-emitting device capable of emitting a laser beam, a photodetector for receiving a laser beam to convert a light signal into an electronic signal, a switching element for controlling various signals corresponding to these devices, a power source circuit for supplying a current, and the like are formed integrally over a same substrate. By forming integrally such a plurality of devices, a power source circuit, and the like over one substrate, fewer components will be allowed. Accordingly, the miniaturization of an optical pick-up device can be realized.
[0025] A light-emitting device capable of emitting a laser beam is formed by the following organic compound material. By using the organic compound material, the light-emitting device can be formed to be thin. Moreover, it becomes possible that the light-emitting device can be formed integrally with a control circuit composed of a thin film transistor, and the like.
[0026] FIG. 4 is a cross-sectional view for showing one state of a light-emitting device 10 capable of producing electroluminescence and emitting laser beam. The light-emitting device is formed by stacking a first electrode 101 , an organic compound layer 102 , and a second electrode 107 over a substrate 101 , sequentially. The organic compound layer 102 is composed of a hole transporting layer 103 , a light-emitting layer 104 , and an electron transporting layer 105 . Further, a hole injecting layer may be formed between the first electrode and the hole transporting layer. An electron injecting layer may be formed between the electron transporting layer and the second electrode. FIG. 4 shows a state in which an electron injecting layer 106 is formed between the electron transporting layer 105 and the second electrode 107 .
[0027] The first electrode 101 serves as an anode for applying a plus voltage. The anode serves as an electrode for injecting holes to the organic compound layer. Hence, a material having a large work function (at least 4.0 eV) is suitable for forming the anode. As the anode material that meets the foregoing requirement, a conductive oxide which is transparent to light such as ITO (Indium Tin Oxide), ZnO (Zinc Oxide), or TiN (Titanium Nitride); or nitrides can be used. Further, the first electrode 101 is required to serve as a reflecting mirror for confining light generated in the light-emitting layer to form a stationary wave. The first electrode 101 may be composed of a plurality of layers for dividing functions of an anode and a reflecting mirror. For example, the first electrode may be formed by stacking a thin film of a conductive oxide which is transparent to light as typified by an ITO and a thin film of a substance which as poor absorption properties for visible light, high reflection properties, and a conductive properties. As the conductive light reflector, Al (aluminum) or the like can be used. In case of forming the first electrode to have functions of both an anode and a reflector, Ag (silver) or (Pt) platinum can be used. Ag or Pt has work functions of at least 4.0 eV and can inject holes to an organic compound layer. At any. rate, the reflecting mirror has preferably the reflectance of from approximately 50 to 95% in order to emit laser beam through the first electrode 101 .
[0028] As the hole injection layer, a material with small ionization potential is used. For example, the material can be selected form the group consisting of a metal oxide, a low molecular organic compound, and a high molecular compound. As a metal oxide, a vanadium oxide, a molybdenum oxide, a ruthenium oxide, an aluminum oxide, and the like can be used. As the low molecular organic compounds, starburst amine typified by m-MTDATA, metallophthalocyanine typified by CuPc, and the like can be used. As the high molecular compounds, conjugated polymer such as polyaniline or polythiophene derivatives can be used. By using the foregoing materials as the hole injecting layer 63 , a hole injecting barrier is reduced to inject holes effectively.
[0029] As the hole transporting layer, known materials such as aromatic amine can be preferably used. For example, 4,4′-bis[N-(1-naphthyl)-N-phenyl-amino]-biphenyl (abbreviated α-NPD), 4,4′,4″-tris(N,N-diphenyl-amino)-triphenyl amine (abbreviated TDATA), or the like can be used. Alternatively, poly(vinyl carbazole) having excellent hole transportation properties as a high molecular material can be used.
[0030] As the light-emitting layer, a metal complex such as tris(8-quinolinolate) aluminum (abbreviated Alq 3 ), tris(4-methyl-8-quinolinolate) aluminum (abbreviated Almq 3 ), bis(10-hydroxybenzo[η]-quinolinato) beryllium (abbreviated BeBq 2 ), bis(2-methyl-8-quinolinolate)-(4-hydroxy-biphenylyl)-aluminum (abbreviated BAlq), bis [2-(2-hydroxyphenyl)-benzooxazolate] zinc (abbreviated Zn(BOX) 2 ), bis [2-(2-hydroxyphenyl)-benzothiazolate] zinc (abbreviated Zn(BTZ) 2 ), or the like can be used. Alternatively, various types of fluorescent dye can be used. Further, phosphorescent materials such as a platinum octaethylporphyrin complex, a tris(phenylpyridine)iridium complex, or a tris(benzylidene-acetonato)phenanthrene europium complex can be efficiently used. Since phosphorescent materials has longer excitation lifetime than that of fluorescent materials, population inversion, that is, the state in which the number of molecules in an excited state is larger that that in a ground state, becomes to be formed easily, which is essential to laser oscillation.
[0031] In addition, light-emitting materials can be used as dopant in the foregoing light-emitting layer 65 . Therefore, a material having larger ionization potential and a band gap than those of light-emitting materials is used as a host material, and a small amount of the foregoing light-emitting material (approximately from 0.001 to 30%) can be mixed into the host material.
[0032] As the electron transporting layer, a metal complex having a quinoline skeleton or a benzoquinoline skeleton or a mixed ligand complex typified by tris(8-quinolinolate)aluminum (abbreviated Alq 3 ). Alternatively, an oxadiazole derivative such as 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviated PBD), or 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviated OXD-7), a triazole derivative such as 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenylyl)-1,2,4-triazole (abbreviated TAZ), or 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (abbreviated p-EtTAZ), phenanthroline derivatives such as bathophenanthroline (abbreviated BPhen), or bathocuproin (abbreviated BCP) can be used.
[0033] As an electron injection material, an alkali metal or alkaline earth metal salt such as calcium fluoride, lithium fluoride, or cesium bromide can be used. The electron injecting layer may be formed by these metal elements contained in another metal or an electron transportation material.
[0034] In case of forming the first electrode as an anode, the second electrode is formed as a cathode. The cathode may be formed by a metal material having comparatively a smaller work function (at least 4.0 eV) compared with that of an organic compound material, an alloy containing the metal material, or a compound material. Specifically, an element of group 1 or 2 in the periodic table, that is, an alkali metal such as Li, Cs, or the like; alkali earth metal such as Mg, Ca, Sr, or the like; an alloy containing the foregoing materials (Mg/Ag, Al/Li) can be used. Alternatively, a transition metal containing a rare earth metal can be used. The cathode can be formed by stacking a metal such as Al, Ag, or ITO (including alloys) over the foregoing materials. In addition, a light-emitting device according to this embodiment need to have a resonator structure. The resonator structure is formed by a reflection of a light between the anode and the cathode. Therefore, as a cathode material, a metal having poor absorption of visible light and high reflectance is preferably used. Specifically, Al (aluminum), Mg (magnesium), or an alloy of the Al or the Mg is preferably used. The cathode is required to have the thickness that does not transmit a light since the cathode is desired to have reflectance of almost 100%.
[0035] The foregoing organic materials can be applied with either wet or dry process. In case of using high molecular materials, spin coating, ink jetting, dip coating, printing, or the like is suitable. On the other hand, in case of using low molecular materials, not s only dip coating or spin coating, but also vapor deposition can be used. The anode material and the cathode material may be applied with vapor deposition, sputtering, or the like.
[0036] An important matter for the light-emitting device is an interval between the anode and the cathode, or between the reflector over the anode and the cathode. Therefore, the thickness of the organic compound layer is an important matter. In order to emit a laser beam, the interval is required to be integral multiple of a half wavelength to amplify a light by forming a stationary wave. For example, in order to amplify light at 400 nm, an interval at least 200 nm is required. Similarly, in order to amplify light at 800 nm, an interval of 400 nm is required. The emission wavelength of the foregoing organic light-emitting materials is mainly in a visible light region. Therefore, in order to amplify the visible light defined as from 400 to 800 nm, the interval between the reflector and the cathode 48 , that is, the thickness of a functional layer is required to be at least 200 nm. In addition, since it should consider that an optical fiber is less for the refraction index of a material, it is required that the value obtained by dividing the thickness by a refraction index is at least 200 nm.
[0037] The foregoing each layer is formed over a substrate 100 formed by glass or quartz, or plastic such as acrylic or polycarbonate. By covering these layers by a protective layer, a solid state light-emitting device capable of emitting a laser beam.
[0038] An example of a light source capable of applying to this embodiment is explained in detail hereinafter. Further, the following explanation is described with reference to FIG. 4 .
[0039] As a substrate 100 for forming a film such as an electrode or a light-emitting layer, a glass substrate such as commercially available alumino silicate glass, barium borosilicate glass, and the like are preferably used. Over the glass substrate, an ITO film is formed by sputtering to have a thickness of from 30 to 100 nm as the first electrode (anode) 101 .
[0040] As the hole transporting layer 103 , 4,4′-bis[N-(1-naphthyl)-N-phenyl-amino]-biphenyl (NPB) is deposited by vacuum vapor deposition. As the light-emitting layer 104 , 4,4′-bis(N-carbazolyl)-biphenyl (CBP) as a host material and an iridium complex, and Ir(tpy) 2 (acac) as a triplet light-emitting material are deposited by co-evaporation. The weight ratio of the CBP and the iridium complex is 10:1. The electron transporting layer 105 is formed thereover by bathocuproin (BCP). The electron injecting layer 106 is formed by calcium fluoride (CaF 2 ). The second electrode 107 is formed by Al (aluminum) by vapor deposition.
[0041] The film thickness of each layer formed by organic materials is determined so as to amplify a light generated in an organic compound layer. Therefore, the light emission from the Ir complex, which is added to the light-emitting layer 104 , or the light emission from the hole transporting layer 103 preferably form a stationary wave by repeating reflection at the interface between the first electrode 101 and the organic compound layer 102 , the interface between the electron transporting layer 105 and the electron injecting layer 106 , or the interface between the electron injecting layer 106 and the second electrode 107 .
[0042] Materials capable of emitting light are the Ir complex and the NPB in the organic materials used here. These materials give light emission in a visible light region (400 to 800 nm). In order to form a stationary wave, the intervals between reflective surfaces are required to be the integral multiple of a half wavelength. For example, in order to form a stationary wave of 400 nm, the intervals are required to be 200 nm or the integral multiple thereof. That is, the thicknesses are required to be integral multiple of 200 nm, such as 200, 400, or 600 nm. Similarly, in order to form a stationary wave of light at 800 nm, the intervals between the reflective surfaces, that is, the thicknesses are required to be integral multiple of 400 nm, such as 400, 800, or 1200 nm.
[0043] By way of example, the hole transporting layer 103 is formed to have a thickness of 135 nm, the light-emitting layer 104 is formed to have a thickness of 30 nm, and the electron transporting layer 105 is formed to have a thickness of 105 nm. As a result, the organic compound layer is formed to have a thickness of 270 nm in total. In this case, given that the refractive index of organic compound layer is 1.7, the wavelength of light capable of forming a stationary wave is the one that is divided 920 nm by integer, that is, 460 nm in a visible light region.
[0044] FIGS. 5A and 5B show emission spectrums of a thus obtained light source. Light emission is obtained by applying direct voltage to a pair of electrodes so that the first electrode serves as an anode and the second electrode serves as a cathode. Light emission can be observed around 6 V. Light emission of tens of thousands candela (Cd) is obtained at applied voltage of 24 V.
[0045] In both spectra shown in FIGS. 5A and 5B , a longitudinal axis represents normalized emission intensity. FIG. 5A shows an emission spectrum of a face emission observed from the side of the first electrode. FIG. 5B shows an emission spectrum of an edge emission observed from a lateral side of the substrate provided with a laminated organic compound layer. As shown in FIG. 5A , intense emission is observed in a wavelength band of from 475 to 650 nm. The emission is produced from the Ir complex.
[0046] The measurement shows that carriers (holes and electrons) are recombined each other almost always in the light-emitting layer 104 to excite the light emission from the Ir complex; however, some carriers are recombined in the hole transporting layer 103 . In case of the face emission, emission intensity varies depending on the variation of a current density. Therefore, the spectra at any current density become to have identical forms, and only the intensity is increased linearly in proportion to the increase of a current density.
[0047] Compared to the spectrum shown in FIG. 5A , the spectrum of the edge emission in FIG. 5B has two features. The first feature is that the waveform of an emission spectrum in the wavelength band of from 475 to 650 nm is different from that in FIG. 5A . The second feature is that a sharp emission spectrum is observed around 460 nm in FIG. 5B . The reason of the former is not clear. On the contrary, the reason of the latter may be considered that a stationary wave is formed by the organic compound layer 102 , and only the light emission at the wavelength is amplified. Actually, as mentioned above, the wavelength that allows stationary wave is 460 nm in the thickness of the organic compound layer 102 . As the most characteristic feature, the intensity of the emission in the wavelength band of from 475 to 600 nm varies in proportion to the increase of a current density, on the contrary, the intensity of another emission spectrum having a peak at around 460 nm further increases than the increase of a current density. Therefore, in the normalized intensity shown in FIG. 5B , only emission at 460 nm is relatively increased.
[0048] Therefore, the measurement shows that the structure of the light-emitting device serves as a resonator of light at 460 nm to amplify the light.
[0049] Hereinafter, an optical pick-up device using the light-emitting device capable of emitting a laser beam is explained.
[0050] FIG. 1 is an explanatory view for showing the structure of an optical pick-up device according to the present invention. A light-emitting device 10 , which is formed by stacking a thin film, capable of emitting laser beam; a first control circuit 12 for controlling a light-emitting device; a photodetector 13 ; a second control circuit 14 for reading the signal for a photodetector; and a power source circuit 15 are integrally formed over a base 200 . The first and the second control circuits are formed to be an integrated circuit by an MOS transistor or a thin film transistor (TFT) using an amorphous or crystalline semiconductor film. Of course, a part of the circuit integrally formed over a semiconductor chip may be mounted over the substrate 200 .
[0051] An optical system 201 composed of a collimator lens 150 , a mirror 151 , an objective lens 152 , and the like may have the structure in which a laser beam emitted from the light-emitting device 10 is condensed, and an optical record medium 153 such as an optical dick is irradiated with the condensed light, subsequently, light reflected from the optical record medium 153 is received by the photodetector 13 . The optical system 201 is not limited to that shown in FIG. 1A . The optical system 201 is formed separately from a base 200 ; however, the optical system 201 is preferably integrated with the base 200 by putting into a casing in the event.
[0052] FIG. 2A shows an optical pick-up device showing the structure that the light-emitting device 10 , the first control circuit 12 , the photodetector 13 , the second control circuit 14 , and the power source circuit 15 are integrated over the substrate 20 that is provided over the base 20 . The optical system 201 such as the mirrors 151 a , 151 b, the objective lens 152 , and the like is arranged between the optical pick-up device and the optical record medium 153 .
[0053] FIG. 2B is a view for showing that the power source circuit 15 is mounted over the base 200 as an independent integrated circuit component. As shown in FIG. 2B , a plurality of the light-emitting devices 10 , a plurality of the first control circuit 12 , a plurality of the photodetector 13 , and a plurality of the second control circuit 14 can be provided. Accordingly, the optical pick-up device can respond to a readout method using a plurality of beams such as a three beams method. Specifically, the optical pick-up device can respond to a three beams method (one main beam and two sub beams) for reproducing an optical disk such as a compact disk and a single beam method for reproducing a DVD (Digital Versatile Disc). Hence, the optical pick-up device can obtain compatibility with the optical record medium.
[0054] The light-emitting device 10 , the photodetector 13 , the first control circuit 12 , and the second control circuit 14 can be formed by appropriately stacking a thin film having conductive properties, semiconductive properties, and insulating properties. The light-emitting device 10 comprises an organic compound layer capable of emitting laser beam. The light-emitting device having the foregoing structure can be utilized.
[0055] The photodetector 13 is formed by an amorphous semiconductor film (such as an amorphous silicon film) or a crystalline semiconductor film (such as a polycrystalline silicon film). Further, the photodetector 13 is formed to have a photoelectric conversion function having a structure of a pin junction, nin junction, pip junction, schottky barrier, or the like. A semiconductor layer for forming a junction is formed to have a thickness of approximately 1 μm. An electrode facing incident light may be formed by a conductive film transparent to light such as ITO. Another electrode may be formed by a metal material such as Al.
[0056] As an element for forming the first control circuit 12 and the second control circuit 14 , a switching element in addition to a resistance element and a capacity element is formed by using a transistor. A typical form of a transistor is a thin film transistor using an amorphous semiconductor film or a crystalline semiconductor film. The thin film transistor can be formed over the substrate 20 formed by glass or plastics. In case of using a single crystalline substrate such as a silicon wafer or an SOI (Silicon On Insulator) substrate for the substrate 20 , a control circuit can be formed by an MOS transistor.
[0057] The foregoing each component can be integrally formed by stacking over one substrate. FIGS. 3A to 3 C show one mode in which these components are integrally formed over the substrate 20 .
[0058] In FIG. 3A , a substrate having an insulating surface such as a glass substrate of alumino-silicate glass, barium borosilicate glass, or the like; a quartz substrate; a plastic substrate of acrylic, polycarbonate, or the like, can be used as the substrate 20 . Alternatively, a single crystalline semiconductor substrate such as a silicon wafer can be is used in addition to an SOI substrate.
[0059] The light-emitting device 10 and the photodetector 13 can be formed integrally over the substrate 20 . Thin film transistors 301 , 302 for controlling these devices are formed by a crystalline semiconductor film or an amorphous semiconductor film. FIG. 3A shows a top gate thin film transistor. The light-emitting device 10 is formed over the thin film transistors 301 , 302 via a first interlayer insulating film 303 . The photodetector 13 is formed over the thin film transistors 301 , 302 via a second interlayer insulating film 304 . The light-emitting device 10 and the photodetector 13 connect to each thin film transistor.
[0060] The light-emitting device 10 is formed by stacking a first electrode 101 , an organic compound layer 102 , and a second electrode 107 . The first electrode 101 is preferably formed by stacking a plurality of conductive films in order to connect to the thin film transistor 302 . As a preferable mode, the first electrode is composed of a first conductive film formed by titanium (Ti) for forming a semiconductor film and a contact of the thin film transistor; a second conductive film formed by aluminum (Al); and a third conductive film formed by titanium nitride (TiN). A material for forming the first electrode 101 is not limited thereto. The conductive film of a top layer is preferably formed by an appropriately selected material as hereinafter described so as to serve as either electrode of the light-emitting device 10 .
[0061] An Al film 30 and an insulating film 31 formed by an inorganic material or an organic material are formed over the first electrode 101 . A bank having an opening portion is formed by selectively etching the Al film 30 and the insulating film 31 . The edge of the opening portion is preferably etched to have an angle of gradient of approximately 45°. Then, a mirror surface is formed by exposing the surface of the Al film 30 .
[0062] The organic compound layer 102 and the second electrode 107 are formed over the first electrode 101 for covering thus formed opening portion of the bank. Further, as shown in FIG. 3A , the side of the organic compound layer 102 is exposed by etching a portion of the edge of the organic compound layer 102 and the second electrode 107 .
[0063] According to the foregoing structure, the organic compound layer 102 is formed to have a thickness of half (half wavelength) of a specified wavelength. Accordingly, light emission reflects between the first electrode 101 and the second electrode 107 , by which a stationary wave of light at the wavelength can be formed. Therefore, a stationary wave of a light at the wavelength can be formed by forming a resonator structure, which makes it possible to emit laser beam.
[0064] As light emitted from the organic compounds, a laser beam having a narrow half band width at a specified wavelength and luminescence in other wavelength band may be emitted simultaneously. In order to remove the luminescence, an optical filter 32 capable of transmitting selectively light at a specified wavelength is provided over a optical path of a laser beam.
[0065] The photodetector 13 can be formed over an insulating surface on which the light-emitting device 10 is formed. Further, the photodetector 13 can be formed over either surface of the interlayer insulating film. The light-emitting device 10 and the photodetector 13 may be arranged depending on the relative positional relationship between these devices and the optical system 201 .
[0066] FIG. 3A shows an example in which the photodetector 13 is formed over the second interlayer insulating film 304 . For example, a wiring 310 is formed as either electrode for connecting to the thin film transistor 301 . An n-type semiconductor layer 311 , a semiconductor layer 312 capable of photoelectric conversion, and a p-type semiconductor layer 313 are sequentially stacked over the wiring 301 . Note that the sequence of lamination of the n-type semiconductor layer 311 and the p-type semiconductor layer 313 may be reversed. Therefore, a pin junction photoelectric conversion layer is formed. An upper electrode 314 may be formed by ITO.
[0067] FIG. 3B shows an example in which the photodetector 13 is formed over a semiconductor layer on which the TFT 302 is formed. The photodetector 13 can be formed by a crystalline semiconductor film as typified by a polycrystalline silicon crystallized by laser annealing. The photodetector 13 is composed of a semiconductor region 116 capable of photoelectric conversion interposed between a p-type semiconductor region 115 and an n-type semiconductor region 117 .
[0068] FIG. 3C shows one mode in which the TFT 304 formed by an amorphous semiconductor film; a photoelectric conversion layer 315 formed by stacking the n-type semiconductor 311 , a semiconductor layer 312 capable of photoelectric conversion, a p-type semiconductor layer 313 , and an upper electrode 314 comprising ITO over the electrode 309 serving as either electrode. Note that the sequence of lamination of the n-type semiconductor 311 and the p-type semiconductor layer 313 may be reversed.
[0069] According to this embodiment, the control circuit using a TFT, the light-emitting device 10 , and the photodetector 13 can be integrally formed over the substrate 20 . An optical pick-up device can be formed by combining the substrate 20 and the optical system.
[0070] By utilizing the optical pick-up device having thus formed structure, a computer, a video reproduction device, and another electric appliance can be completed.
[0071] FIG. 6A shows an example of completing a computer by practicing the present invention. The computer is composed of a main body 2201 , a casing 2202 , a display portion 2203 , a keyboard 2204 , an external connection port 2205 , a pointing mouse 2206 , and a CD-R/RW drive 2207 . The optical pick-up device according to the invention can be used for the CD-R/RW drive 2207 . The optical pick-up device has the structure in which the foregoing light-emitting device and TFT are formed over the substrate. A thin, lightweight, and highly portable computer can be completed.
[0072] FIG. 6B shows an example of completing a video reproduction device (DVD player) by practicing the invention. The video reproduction device is composed of a 5 main body 2401 , a casing 2402 , a display portion A 2403 , a display portion B 2404 , a record medium readout unit 2405 , operation keys 2406 , speaker portions 2407 , and the like. A thin, lightweight, and highly portable video reproduction device can be completed by utilizing the optical pick-up device according to the invention for the record medium readout unit 2405 .
[0073] Although the present invention has been fully described by way of examples with reference to the accompanying drawings, it is to be understood that various changes and modifications will be apparent to those skilled in the art. Therefore, unless otherwise such changes and modifications depart from the scope of the present invention hereinafter described, they should be construed as being included therein. | It is an object of the present invention to provide an optical pick-up device capable of being miniaturized by reducing the number of components. The present invention provides an optical pick-up device including a light-emitting device having an organic compound that emits laser light upon applying current. The light-emitting device interposes an organic compound layer between a pair of electrodes. The organic compound layer, which is a main component, has a layer configuration for emitting a laser beam. In the layer configuration, the thickness of each layer is determined in consideration of the wavelength of laser oscillation. The organic compound layer is composed of a plurality of layers, each of which has different properties such as carrier transportation properties or light-emitting properties. The organic compound layer is preferably formed to have a so-called resonator structure formed via a reflecting layer. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to data processing systems, and more particularly, to docking systems including mechanisms for transferring information between buses.
2. Description of Related Art
Computers can use buses to transfer data between a host processor and various devices, such as memory devices and input/output devices. As used herein an "input/output" device is a device that either generates an input or receives an output (or does both). Thus "input/output" is used in the disjunctive. These buses may be arranged in a hierarchy with the host processor connected to a high level bus reserved for exchanging the data most urgently needed by the processor. Lower level buses may connect to devices having a lower priority.
Other reasons exist for providing separate buses. Placing an excessive number of devices on one bus produces high loading. Such loading makes a bus difficult to drive because of the power needed and the delays caused by signaling so many devices. Also, some devices on a bus may periodically act as a master and request control over a bus in order to communicate with a slave device. By segregating some devices on a separate bus, master devices can communicate with other devices on the lower level bus without tying up the bus used by the host processor or other masters.
The PCI bus standard is specified by the PCI Special Interest Group of Hillsboro, Oreg. The PCI bus features a 32-bit wide, multiplexed address-data (AD) bus portion, and can be expanded to a 64-bit wide AD bus portion. Maintaining a high data throughput rate (e.g., a 33 MHZ clock rate) on the PCI bus leads to a fixed limitation on the number of electrical AC and DC loads on the bus. Speed considerations also limit the physical length of the bus and the capacitance that can be placed on the bus by the loads, while future PCI bus rates (e.g., 66 MHZ) will exacerbate the electrical load and capacitance concerns. Failure to observe these load restrictions can cause propagation delays and unsynchronized operation between bus devices.
To circumvent these loading restrictions, the PCI bus standard specifies a bridge to allow a primary PCI bus to communicate with a secondary PCI bus through such a bridge. Additional loads may be placed on the secondary bus without increasing the loading on the primary bus. For bridges of various types see U.S. Pat. Nos. 5,548,730 and 5,694,556.
The PCI bridge observes a hierarchy that allows an initiator or bus master on either bus to complete a transaction with a target on the other bus. As used herein, hierarchy refers to a system for which the concept of a higher or lower level has meaning. For example, a PCI bus system is hierarchical on several scores. An ordering of levels is observed in that a high level host processor normally communicates from a higher level bus through a bridge to a lower level bus. An ordering of levels is also observed in that buses at equal levels do not communicate directly but through bridges interconnected by a higher level bus. Also, an ordering of levels is observed in that data is filtered by their addresses before being allowed to pass through a bridge, based on the levels involved. Other hierarchical systems exist that may observe an ordering of levels by using one or more of the foregoing concepts, or by using different concepts.
Some personal computers have slots for add-on cards, which allow the card to connect to a peripheral bus in the computer. Because a user often needs additional slots, expansion cards have been designed that will connect between the peripheral bus and an external unit that offers additional slots for add-on cards. For systems for expanding a bus, see U.S. Pat. Nos. 5,006,981; 5,191,657; and 5,335,329. See also U.S. Pat. No. 5,524,252.
For portable computers, special considerations arise when the user wishes to connect additional peripheral devices. Often a user will bring a portable computer to a desktop and connect through a docking station or port replicator to a keyboard, monitor, printer or the like. A user may also wish to connect to a network through a network interface card in the docking station. At times, a user may need additional devices such as hard drives or CD-ROM drives. While technically possible to a limited extent, extending a bus from a portable computer through a cable is difficult because of the large number of wires needed and because of latencies caused by a cable of any significant length.
In U.S. Pat. No. 5,696,949 a host chassis has a PCI to PCI bridge that connects through a cabled bus to another PCI to PCI bridge in an expansion chassis. This system is relatively complicated since two independent bridges communicate over a cabled bus. This cabled bus includes essentially all of the lines normally found in a PCI bus. This approach employs a delay technique to deal with clock latencies associated with the cabled bus. A clock signal generated on the expansion side of the cabled bus: (a) is sent across the cabled bus, but experiences a delay commensurate with the cable length; and (b) is delayed an equivalent amount on the expansion side of the cabled bus by a delay line there, before being used on the expansion side. Such a design complicates the system and limits it to a tuned cable of a pre-designed length, making it difficult to accommodate work spaces with various physical layouts.
U.S. Pat. No. 5,590,377 shows a primary PCI bus in a portable computer being connected to a PCI to PCI bridge in a docking station. When docked, the primary and secondary buses are physically very close. A cable is not used to allow separation between the docking station and the portable computer. With this arrangement, there is no interface circuitry between the primary PCI bus and the docking station. See also U.S. Pat. No. 5,724,529.
U.S. Pat. No. 5,540,597 suggests avoiding additional PCMCIA connectors when connecting a peripheral device to a PC card slot in a portable computer, but does not otherwise disclose any relevant bridging techniques.
U.S. Pat. No. 4,882,702 and show a programmable controller for controlling industrial machines and processes. The system exchanges data serially with a variety of input/output modules. One of these modules may be replaced with an expansion module that can serially communicate with several groups of additional input/output modules. This system is not bridge-like in that the manner of communicating with the expansion module is different than the manner of communicating with the input/output modules. For the expansion module the system changes to a block transfer mode where a group of status bytes are transferred for all the expansion devices. This system is also limited to input/output transactions and does not support a variety of addressable memory transactions. See also U.S. Pat. Nos. 4,413,319; and 4,504,927.
In U.S. Pat. No. 5,572,525 another bus designed for instrumentation (IEEE 488 General Purpose Instrumentation Bus) connects to an extender that breaks the bus information into packets that are sent serially through a transmission cable to another extender. This other extender reconstructs the serial packets into parallel data that is applied to a second instrumentation bus. This extender is an intelligent system operating through a message interpretation layer and several other layers before reaching the parallel to serial conversion layer. Thus this system is unlike a bridge. This system is also limited in the type of transactions that it can perform. See also U.S. Pat. No. 4,959,833.
U.S. Pat. No. 5,325,491 shows a system for interfacing a local bus to a cable with a large number of wires for interfacing with remote peripherals. See also U.S. Pat. Nos. 3,800,097; 4,787,029; 4,961,140; and 5,430,847.
The Small Computer System Interface (SCSI) defines bus standards for a variety of peripheral devices. This SCSI bus is part of an intelligent system that responds to high-level commands. Consequently, SCSI systems require software drivers to enable hardware to communicate to the SCSI bus. This fairly complicated system is quite different from bridges such as bridges as specified under the PCI standard. A variety of other complex techniques and protocols exist for transferring data, including Ethernet, Token Ring, TCP/IP, ISDN, FDDI, HIPPI, ATM, Fibre Channel, etc., but these bear little relation to bridge technology.
See also U.S. Pat. Nos. 4,954,949; 5,038,320; 5,111,423; 5,446,869; 5,495,569; 5,497,498; 5,507,002; 5,517,623; 5,530,895; 5,542,055; 5,555,510; 5,572,688; and 5,611,053.
Accordingly, there is a need for an improved system for transferring information between buses.
SUMMARY OF THE INVENTION
In accordance with the illustrative embodiments demonstrating features and advantages of the present invention, there is provided a docking system for giving a portable computer access over a first bus to a second bus. The first bus and the second bus are each adapted to separately connect to respective ones of a plurality of bus-compatible devices. The docking system has a link, together with a first and a second interface means. The first interface means is coupled between the first bus and the link. The second interface means is coupled between the second bus and the link. The first interface means and the second interface means are operable to (a) send bus-related information through the link in a format different from that of the first bus and the second bus, and (b) allow the portable computer, communicating through the first bus, to individually address one or more of the bus-compatible devices on the second bus using on the first bus substantially the same type of addressing as is used to access devices on the first bus.
In accordance with another aspect of the invention a method is provided for docking a portable computer having a first bus, in order to communicate with a second bus over a link. The first bus and the second bus each are adapted to separately connect to respective ones of a plurality of bus-compatible devices. The method includes the step of sending bus-related information through the link in a format different from that of the first bus and the second bus. Another step is allowing the portable computer, communicating through the first bus, to individually address one or more of the bus-compatible devices on the second bus using on the first bus substantially the same type of addressing as is used to access devices on the first bus.
By employing apparatus and methods of the foregoing type, an improved system is achieved for transferring information between buses. In one preferred embodiment, two buses communicate over a duplex link formed with a pair of simplex links, each employing twisted pair or twin axial lines (depending on the desired speed and the anticipated transmission distance). Information from the buses are first loaded onto FIFO (first-in first-out) registers before being serialized into frames for transmission over the link. Received frames are deserialized and loaded into FIFO registers before being placed onto the destination bus. Preferably, interrupts, error signals, and status signals are sent along the link.
In this preferred embodiment, address and data are taken from a bus one transaction at a time, together with four bits that act either as control or byte enable signals. Two or more additional bits may be added to tag each transaction as either: an addressing cycle; acknowledgment of a non-posted write; data burst; end of data burst (or single cycle). If these transactions are posted writes they can be rapidly stored in a FIFO register before being encoded into a number of frames that are sent serially over a link. When pre-fetched reads are allowed, the FIFO register can store pre-fetched data in case the initiator requests it. For single cycle writes or other transactions that must await a response, the bridge can immediately signal the initiator to wait, even before the request is passed to the target.
In a preferred embodiment, one or more of the buses follows the PCI or PCMCIA bus standard (although other bus standards can be used instead). The preferred apparatus then operates as a bridge with a configuration register that is loaded with information specified under the PCI standard. The apparatus can transfer information between buses depending upon whether the pending addresses fall within a range embraced by the configuration registers. This scheme works with devices on the other side of the bridge, which can be given unique base addresses to avoid addressing conflicts.
In one highly preferred embodiment, the apparatus may be formed as two separate application-specific integrated circuits (ASIC) joined by a cable. Preferably, these two integrated circuits have the same structure, but can act in two different modes in response to a control signal applied to one of its pins. Working with hierarchical buses (primary and secondary buses) these integrated circuits will be placed in a mode appropriate for its associated bus. The ASIC associated with the secondary bus preferably has an arbiter that can grant masters control of the secondary bus. This preferred ASIC can also supply a number of ports to support a mouse and keyboard, as well as parallel and serial ports.
When used with a portable computer, one of the ASIC's can be assembled with a connector in a package designed to fit into a PC card slot following the PCMCIA standard. This ASIC can connect through a cable to the other ASIC, which can be located in a docking station. Accordingly, the apparatus can act as a bridge between a CardBus and a PCI bus located in a docking station. Since the preferred ASIC can also provide a port for a mouse and keyboard, this design is especially useful for a docking station. Also, the secondary PCI bus implemented by the ASIC can connect to a video card or to a video processing circuit on the main dock circuit board in order to drive a monitor.
In some embodiments, one ASIC will be mounted in the portable computer by the original equipment manufacturer (OEM). This portable computer will have a special connector dedicated to the cable that connects to the docking station with the mating ASIC. For such embodiments, the existence within the preferred ASIC of ports for various devices can be highly advantageous. An OEM can use this already existing feature of the ASIC and thereby eliminate circuitry that would otherwise have been needed to implement such ports.
BRIEF DESCRIPTION OF THE DRAWINGS
The above brief description as well as other objects, features and advantages of the present invention will be more fully appreciated by reference to the following detailed description of presently preferred but nonetheless illustrative embodiments in accordance with the present invention when taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a schematic block diagram showing a bridge split by a link within the bridge, in accordance with principles of the present invention;
FIG. 2 is a schematic block diagram showing a bridge in accordance with principles of the present invention using the link of FIG. 1;
FIG. 3 is a schematic block diagram showing the bridge of FIG. 2 used in a docking system in accordance with principles of the present invention;
FIG. 4 is a cross-sectional view of the cable of FIG. 3;
FIG. 5 is a schematic illustration of the bridge of FIG. 3 shown connected to a portable computer and a variety of peripheral devices; and
FIG. 6 shows a docking station similar to that of FIG. 5 but with the portable computer modified to contain an application-specific integrated circuit designed to support a link to the docking station.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, a bridge is shown connecting between a first bus 10 and a second bus 12 (also referred to as primary bus 10 and secondary bus 12). These buses may be PCI or PCMCIA 32-bit buses, although other types of buses are contemplated and the present disclosure is not restricted to any specific type of bus. Buses of this type will normally have address and data lines. In some cases, such as with the PCI bus, address and data are multiplexed onto the same lines. In addition, these buses will have signaling lines for allowing devices on the bus to negotiate transactions. For the PCI standard, these signaling lines will include four lines that are used either for control or byte enabling (C/BE[3:0]). Others signaling lines under the PCI standard exist for gaining control over the bus, for handshaking, and the like (e.g., FRAME#, TRDY#, IRDY#, STOP#, DEVSEL#, etc.)
Buses 10 and 12 are shown connecting to a first interface means 14 and 30 second interface means 16, respectively (also referred to as interfaces 14 and 16). Bus information selected for transmission by interfaces 14 and 16 are loaded into registers 18 and 20, respectively. Incoming bus information that interfaces 14 and 16 select for submission to the buses are taken from registers 22 and 24, respectively. In one embodiment, registers 18-24 are each 16×38 FIFO registers, although different types of registers having different dimensions may be used in alternate embodiments.
In this embodiment, registers 18-24 are at least 38 bits wide. Thirty six of those bits are reserved for the 4 control bits (C/BE#[3:0]) and the 32 address/data bits (AD[31:0]) used under the PCI bus standard. The remaining two bits can be used to send additional tags for identifying the nature of the transaction associated therewith. Other bits may be needed to fully characterize every contemplated transaction. Transactions can be tagged as: addressing cycle; acknowledgment of a non-posted write; data burst; end of data burst (or single cycle). Thus outgoing write transactions can be tagged as a single cycle transaction or as part of a burst. Outgoing read requests can also be tagged as part of a burst with a sequence of byte enable codes (C/BE) for each successive read cycle of the burst. It will be appreciated that other coding schemes using a different number of bits can be used in other embodiments.
The balance of the structure illustrated in FIG. 1 is a link designed to establish duplex communications between interfaces 14 and 16 through registers 18-24. For example, encoder 28 can accept the oldest 38 bits from register 20 and parse it into five bytes (40 bits). The extra two bits of the last byte are encoded to signify the interrupts, status signals and error signals that may be supplied from block 34.
Each of these five bytes is converted into a 10 bit frame that can carry the information of each byte, as well as information useful for regulating the link. For example, these frames can carry comma markers, idle markers, or flow control signals, in a well-known fashion. A transceiver system working with bytes that were encoded into such 10 bit frames is sold commercially by Hewlett Packard as model number HDMP-1636 or -1646. Frames produced by encoder 28 are forwarded through transmitter 44 along simplex link 46 to receiver 48, which supplies the serial information to decoder 30. Likewise, encoder 26 forwards serial information through transmitter 38 along simplex link 40 to receiver 42, which supplies the serial information to decoder 32.
Flow control may be necessary should FIFO registers 22 or 24 be in danger of overflowing. For example, if FIFO register 22 is almost full, it supplies a threshold detect signal 36 to encoder 26, which forwards this information through link 40 to decoder 32. In response, decoder 32 issues a threshold stop signal 50 to encoder 28, which then stops forwarding serial information, thereby preventing an overflow in FIFO register 22. In a similar fashion, a potential overflow in FIFO register 24 causes a threshold detect signal 52 to flow through encoder 28 and link 46 to cause decoder 30 to issue a threshold stop signal 54, to stop encoder 26 from sending more frames of information. In some embodiments, the system will examine the received information to determine if it contains transmission errors or has been corrupted in some fashion. In such event the system can request a retransmission of the corrupted information and thereby ensure a highly reliable link.
In this embodiment, elements 14, 18, 22, 26, 30, 38 and 48 are part of a single, application specific integrated circuit (ASIC) 56. Elements 16, 20, 24, 28, 32, 42 and 44 are also part of an ASIC 58. As described further hereinafter, first ASIC 56 and second ASIC 58 have an identical structure but can be operated in different modes. It will be appreciated that other embodiments may not use ASIC's but may use instead alternate circuitry, such as a programable logic device, or the like. As shown herein, ASIC 56 is operating in a mode designed to service primary bus 10, and (for reasons to be described presently) will be sending outputs to block 57. In contrast block 34 of ASIC 58 will receive inputs from block 34.
Encoders 26 and 28 have optional parallel outputs 27 and 29, respectively, for applications requiring such information. Also for such applications, decoders 30 and 32 have parallel inputs 31 and 33, respectively. These optional inputs and outputs may be connected to an external transceiver chip, such as the previously mentioned device offered by Hewlett Packard as model number HDMP-1636 or -1646. These devices will still allow the system to transmit serial information, but by means of an external transceiver chip. This allows the user of the ASIC's 56 and 58 more control over the methods of transmission over the link.
Referring to FIG. 2, previously mentioned ASIC's 56 and 58 are shown in further detail. The previously mentioned encoders, decoders, transmitters, receivers, and FIFO registers are combined into blocks 60 and 62, which are interconnected by a duplex cable formed of previously mentioned simplex links 40 and 46. Previously mentioned interface 14 is shown connected to primary bus 10, which is also connected to a number of bus-compatible devices 64. Similarly, previously mentioned interface 16 is shown connected to secondary bus 12, which is also connected to a number of bus-compatible devices 66. Devices 64 and 66 may be PCI-compliant devices and may operate as memory devices or input/output devices.
Interface 14 a shown connected to a first register means 68, which acts as a configuration register in compliance with the PCI standard. Since this system will act as a bridge, configuration registers 68 will have the information normally associated with a bridge. Also, configuration registers 68 will contain a base register and limit register to indicate a range or predetermined schedule of addresses for devices that can be found on the secondary bus 12. Under the PCI standard, devices on a PCI bus will themselves each have a base register, which allows mapping of the memory space and/or I/O space. Consequently, the base and limit registers in configuration registers 68 can accommodate the mapping that is being performed by individual PCI devices. The information on configuration registers 68 are mirrored on second configuration register 67 (also referred to as a second configuration means). This makes the configuration information readily available to the interfaces on both sides of the link.
In this embodiment, ASIC 58 has an arbiter 70. Arbiters are known devices that accept requests from masters on secondary bus 12 for control of the bus. The arbiter has a fair algorithm that grants the request of one of the contending masters by issuing it a grant signal. In this hierarchical scheme, secondary bus 12 requires bus arbitration, but primary bus 10 will provide its own arbitration. Accordingly, ASIC 56 is placed in a mode where arbiter 72 is disabled. The modes of ASIC's 56 and 58 are set by control signals applied to control pins 74 and 76, respectively. Because of this mode selection, the signal directions associated with blocks 57 and 34 will be reversed.
In this embodiment, ASIC 58 is in a mode that implements a third bus 78. Bus 78 may follow the PCI standard, but is more conveniently implemented in a different standard. Bus 78 connects to a number of devices that act as a port means. For example, devices 80 and 82 can implement PS/2 ports that can connect to either a mouse or a keyboard. Device 84 implements an ECP/EPP parallel port for driving a printer or other device. Device 86 implements a conventional serial port. Devices 80, 82, 84 and 86 are shown with input/output lines 81, 83, 85 and 87, respectively. Devices 80-86 may be addressed on bus 10 as if they were PCI devices on bus 12. Also in this embodiment, a bus 88 is shown in ASIC 56, with the same devices as shown on bus 78 to enable an OEM to implement these ports without the need for separate input/output circuits.
Referring to FIG. 3, previously mentioned ASIC 58 is shown in a docking station 130 connected to an oscillator 91 for establishing a remote and internal clock. ASIC 58 has its lines 81 and 83 connected through a connection assembly 90 for connection to a keyboard and mouse, respectively. Serial lines 85 and parallel lines 87 are shown connected to transceivers 92 and 94, respectively, which then also connect to connection assembly 90 for connection to various parallel and serial peripherals, such as printers and modems.
ASIC 58 is also shown connected to previously mentioned secondary bus 12. Bus 12 is shown connected to an adapter card 96 to allow the PCI bus 12 to communicate with an IDE device such as a hard drive, backup tape drive, CD-ROM drive, etc. Another adapter card 98 is shown for allowing communications from bus 12 to a universal serial port (USB). A network interface card 100 will allow communications through bus 12 to various networks operating under the Ethernet standard, Token Ring standard, etc. Video adapter card 102 (also referred to as a video means) allows the user to operate another monitor. Add-on card 104 may be one of a variety of cards selected by the user to perform a useful function. While this embodiment shows various functions being implemented by add-on cards, other embodiments may implement one or more of these function on a common circuit board in the dock (e.g., all functions excluding perhaps the IDE adapter card).
ASIC 58 communicates through receiver/transmitter 106, which provides a physical interface through a terminal connector 108 to cable 40, 46. Connector 108 may be a 20 pin connector capable of carrying high speed signals with EMI shielding (for example a low force helix connector of the type offered by Molex Incorporated), although other connector types may be used instead. The opposite end of cable 40, 46 connects through a gigabit, terminal connector 110 to physical interface 112, which acts as a receiver/transmitter. Interface 112 is shown connected to previously mentioned first ASIC 56, which is also shown connected to an oscillator 114 to establish a local clock signal. This specific design contemplates using an external transmitter/receiver (external SERDES of lines 27, 29, 31, and 33 of FIG. 1), although other embodiments can eliminate these external devices in favor of the internal devices in ASIC's 56 and 58.
This embodiment is adapted to cooperate with a portable computer having a PCMCIA 32-bit bus 10, although other types of computers can be serviced. Accordingly, ASIC 56 is shown in a package 116 having an outline complying with the PCMCIA standard and allowing package 116 to fit into a slot in a portable computer. Therefore, ASIC 56 has a connector 118 for connection to bus 10. Cable 40, 46 will typically be permanently connected to package 116, but a detachable connector may be used in other embodiments, where a user wishes to leave package 116 inside the portable computer.
Power supply 120 is shown producing a variety of supply voltages used to power various components. In some embodiments, one of these supply lines can be connected directly to the portable computer to charge its battery.
Referring to FIG. 4, the previously mentioned simplex links 40 and 46 are shown as twin axial lines 40A and 46A, wrapped with individual shields 40B and 46B. A single shield 122 encircles the lines 40 and 46. Four parallel wires 124 are shown (although a greater number may be used in other embodiments) mounted around the periphery of shields 122 for various purposes. These wires 124 may carry power management signals, dock control signals or other signals that may be useful in an interface between a docking station and a portable computer. While twin axial lines offer high performance, twisted pairs or other transmission media may be used in other embodiments where the transmission distance is not as great and where the bit transfer speed need not be as high. While a hard wire connection is illustrated, in other embodiments a wireless or other type of connection can be employed instead.
Referring to FIG. 5, previously mentioned package 116 is shown in position to be connected to a PCMCIA slot in portable computer 126. Computer 126 is shown having primary bus 10 and a host processor 128. Package 116 is shown connected through cable 40, 46 to previously mentioned connector 108 on docking station 130. Previously mentioned docking station 130 is shown connecting through PS/2 ports to keyboard 132 and mouse 134. A printer 136 is shown connected to a parallel port in docking station 130. Previously mentioned video means 102 is shown connected to a monitor 138. Docking station 130 is also shown with an internal hard drive 140 connecting to the adapter card previously mentioned. A CD-ROM drive 142 is also shown mounted in docking station 130 and connects to the secondary bus through an appropriate adapter card (not shown). Previously mentioned add-on card 104 is shown with its own cable 144.
Referring to FIG. 6, a modified portable computer 126' is again shown with a host processor 128 and primary bus 10. In this embodiment however, portable computer 126' contains previously mentioned ASIC 56. Thus there is no circuitry required (other than perhaps drivers) between ASIC 56 and cable 40,46. In this case, the laptop end of cable 40, 46 has a connector 143 similar to the one on the opposite end of the cable (connector 108 of FIG. 5). Connector 143 is designed to mate with connector 141 and support the high-speed link. As before, connectors 141 and 143 can also carry various power management signals, and other signals associated with a docking system.
An important advantage of this arrangement is the fact that ASIC 56 contains circuitry for providing ports, such as a serial port, a parallel port, PS/2 ports for a mouse and keyboard, and the like. Since portable computer 126' would ordinarily provide such ports, ASIC 56 simplifies the design of the portable computer. This advantage is in addition to the advantage of having a single ASIC design (that is, ASIC's 56 and 58 are structured identically), which single design is capable of operating at either the portable computer or the docking station, thereby simplifying the ASIC design and reducing stocking requirements, etc.
To facilitate an understanding of the principles associated with the foregoing apparatus, its operation will be briefly described. This operation will be described in connection with the docking system of FIGS. 3 and 5 (which generally relates to FIG. 2), although operation would be similar for other types of arrangements. For the docking system, a connection is established by plugging package 116 (FIG. 5) into portable computer 126. This establishes a link between the primary bus 10 and ASIC 56 (FIG. 3).
At this time an initiator (the host processor or a master) having access to primary bus 10 may assert control of the bus. An initiator will normally send a request signal to an internal arbiter (not shown) that will eventually grant control to this initiator. In any event, the initiator asserting control over primary bus 10 will exchange the appropriate handshaking signals and drive an address onto the bus 10. Control signals simultaneously applied to the signaling lines of bus 10 will indicate whether the transaction is a read, write, or other type of transaction.
Interface 14 (FIG. 2) will examine the pending address and determine whether it represents a transaction with devices on the other side of the bridge (that is, secondary bus 12) or with the bridge itself. Configuration register 68 has already been loaded in the usual manner with information that indicates a range of addresses defining the jurisdiction of the interface 14.
Assuming a write transaction is pending on bus 10, interface 14 will transfer 32 address bits together with four control bits (PCI standard) to FIFO register 18 (FIG. 1). Encoder 26 will add at least two additional bits tagging this information as an addressing cycle. The information is then broken into frames that can carry flow control and other signals before being transmitted serially over link 40.
Without waiting, interface 14 will proceed to a data cycle and accept up to 32 bits of data from bus 10 together with four byte enable bits. As before, this information will be tagged, supplemented with additional information and broken into frames for serial transmission over link 40. This transmitted information will be tagged to indicate whether it is part of a burst or a single cycle.
Upon receipt, decoder 32 restores the frames into the original 38 bit format and loads the last two described cycles onto the stack of register 24. Interface 16 eventually notices the first cycle as an addressing cycle in a write request. Interface 16 then negotiates control over bus 12 in the usual fashion and applies the address to bus 12. A device on bus 12 will respond to the write request by performing the usual handshaking.
Next, interface 16 will drive the write data stacked on register 24 into bus 12. If this transaction is a burst, interface 16 will continue to drive data onto bus 12 by fetching it from register 24. If however this transaction is a single cycle write, interface 16 will close the transaction on bus 12 and load an acknowledgment into register 20. Since this acknowledgment need not carry data or address information, a unique code may be placed into register 20, so that encoder 28 can appropriately tag this line before parsing it into frames for transmission over link 46. Upon receipt, decoder 30 will produce a unique code that is loaded into register 22 and eventually forwarded to interface 14, which sends an acknowledgment to the device on bus 10 that the write has succeeded.
If the initiator instead sets its control bits during the address cycle to indicate a read request, interface 14 would also accept this cycle, if it has jurisdiction. Interface 14 will also signal the initiator on bus 10 that it is not ready to return data (e.g., a retry signal, which may be the stop signal as defined under the PCI standard). The initiator can still start (but not finish) a data cycle by driving its signaling lines on bus 10 with byte enable information. Using the same technique, the address information, followed by the byte enable information, will be accepted by interface 14 and loaded with tags into register 18. These two lines of information will be then encoded and transmitted serially over link 40. Upon receipt, this information will be loaded into the stack of register 24. Eventually, interface 16 will notice the first item as a read request and drive this address information onto secondary bus 12. A device on bus 12 will respond and perform the appropriate handshaking. Interface 16 will then forward the next item of information from register 24 containing the byte enables, onto bus 12 so the target device can respond with the requested data. This responsive data is loaded by interface 16 into register 20. If pre-fetching is indicated, interface 16 will initiate a number of successive read cycles to accumulate data in register 20 from sequential addresses that may or may not be requested by the initiator.
As before, this data is tagged, broken into frames and sent serially over link 46 to be decoded and loaded into register 22. The transmitted data can include pre-fetched data that will be accumulated in register 22. Interface 14 transfers the first item of returning data onto primary bus 10, and allows the initiator to proceed to another read cycle if desired. If another read cycle is conducted as part of a burst transaction, the requested data will already be present in register 22 for immediate delivery by interface 14 to bus 10. If these pre-fetched data are not requested for the next cycle, then they are discarded.
Eventually the initiator will relinquish control of bus 10. Next, an initiator on bus 12 may send a request for control of bus 12 to arbiter 70 (FIG. 2). If arbiter 70 grants control, the initiator may make a read or write request by driving an address onto bus 12. Interface 16 will respond if this address does not fall within the jurisdictional range of addresses specified in configuration register 67 (indicating the higher level bus 10 may have jurisdiction). In the same manner as before, but with a reversed flow over links 40, 46, interface 16 may accept address and data cycles and communicate them across link 40, 46. Before being granted bus 10, interface 14 will send a request to an arbiter (not shown) associated with bus 10.
In some instances, an initiator on primary bus 10 will wish to read from, or write to, port means 80, 82, 84, or 86. These four items are arranged to act as devices under the PCI standard. Interface 16 will therefore act as before, except that information will be routed not through bus 12, but through bus 78.
Other types of transactions may be performed, including reads and writes to the configuration registers 67 and 68 (FIG. 2). Other types of transactions, as defined under the PCI standard (or other bus standards) may be performed as well.
Interrupt signals may be generated by the ports or other devices in ASIC 58. Also external interrupts may be received as indicated by block 34. As noted before, interrupt signals may be embedded in the code sent over link 46. Upon receipt, system 60 decodes the interrupts and forwards them on to block 57, which may be simply one or more pins from ASIC 56 (implementing, for example, INTA of the PCI standard). This interrupt signal can either be sent over the bus 10 or to an interrupt controller that forwards interrupts to the host processor. System errors may be forwarded in a similar fashion to produce an output on a pin of ASIC 56 that can be routed directly to bus 10 or processed using dedicated hardware. The designer may wish to send individual status signals, which can be handled in a similar fashion along link 40, 46.
It is appreciated that various modifications may be implemented with respect to the above described, preferred embodiment. In other embodiments the illustrated ASIC's may be divided into several discrete packages using in some cases commercially available integrated circuits. Also, the media for the link may be wire, fiber-optics, infrared light, radio frequency signals, or other media. In addition, the primary and secondary buses may each have one or more devices, and these devices may be in one or more categories, including memory devices and input/output devices. Moreover, the devices may operate at a variety of clock speeds, bandwidths and data rates. Furthermore, transactions passing through the bridge may be accumulated as posted writes or as pre-fetched data, although some embodiments will not use such techniques. Also, the bridge described herein can be part of a hierarchy using a plurality of such bridges having their primary side connected to the same bus or to buses of an equivalent or different level. Additionally, the illustrated ports can be of a different number or type, or can be eliminated in some embodiments. Also, the illustrated arbiter can be eliminated for secondary buses that are not design to be occupied by a master. While a sequence of steps is described above, in other embodiments these steps may be increased or reduced in number, or performed in a different order, without departing from the scope of the present invention.
Obviously, many modifications and variations of the present invention are possible in 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 docking system can give a portable computer access over a first bus in the portable computer to a second bus in a docking station. The first bus and the second bus are each adapted to separately connect to respective ones of a plurality of bus-compatible devices. The docking system has a serial link cooperating with a first and a second interface to act as a single bridge. The first interface is coupled between the first bus and the link. The second interface is coupled between the second bus and the link. The first interface and the second interface are operable to (a) send bus-related information through the link in a format different from that of the first bus and the second bus, and (b) allow the portable computer, communicating through the first bus, to individually address one or more of the bus-compatible devices on the second bus using on the first bus substantially the same type of addressing as is used to access devices on the first bus. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of growing a silicon crystal in a liquid phase. A silicon crystal produced by the method of the present invention can be used in silicon devices having a large area such as solar cells and picture element driving circuits for liquid crystal display devices.
2. Related Background Art
Solar cells are prevailing as electric power sources which are systematically linked with driving power sources for various kinds of appliances and commercial line power. It is desirable to manufacture solar cells at low cost. For example, it is desired to produce solar cells on inexpensive substrates at a low cost. Silicon is generally used as a semiconductor for composing solar cells. Single crystalline silicon is extremely excellent from a viewpoint of efficiency of converting light energy into electric power, that is, photoelectric conversion efficiency. From the viewpoints of enlargement of area and reduction of manufacturing cost, on the other hand, amorphous silicon is advantageous. In recent years, polycrystalline silicon has been used for the purpose of obtaining a cost as low as that of amorphous silicon and a photoelectric conversion efficiency as high as that of single crystalline silicon.
However, it cannot be said that the expensive crystalline materials are sufficiently utilized by a method which is conventionally adopted to manufacture silicon devices using single crystalline silicon or polycrystalline silicon since the method is configured to slice a lump crystal to form plate-like substrates and is hardly capable of preparing substrates which have thicknesses of 0.3 mm or smaller, thereby allowing the substrates to have thicknesses larger than a thickness (20 μm to 50 μm) generally required to absorb incident rays. Furthermore, there has recently been proposed the spin method of forming a silicon sheet by flowing drops of melted silicon into a template. However, a silicon sheet formed by this method has a quality insufficient for use as a semiconductor and cannot provide a photoelectric conversion efficiency which is so high as that in the case of using a general crystalline silicon.
There has been proposed and actually applied to trial production of a solar cell under the circumstances described above, an idea of growing on an inexpensive substrate a silicon crystal of a good quality until it has a required and sufficient thickness and forming an active region (for example, a photoelectric conversion region) thereon. Moreover, there has been proposed an idea of growing a silicon crystal epitaxially on a substrate of a good quality and then peeling off the silicon crystal and reusing the substrate.
On a premise that large area devices such as solar cells are to be produced in mass, however, it is not so easy to grow a silicon crystal until it has a thickness required for absorbing incident rays. A silicon crystal of a good quality is generally grown by the thermal CVD method of thermally decomposing a raw material gas such as silane chloride. In order to grow a single crystal at a high rate on the order of 1 μm/minute in particular, it is typical to use the so-called epitaxial growing furnace. However, such a growing furnace is not only unsuited to mass production since it can treat 10 wafers at most at one batch, but also requires a high raw material cost since it utilizes a raw material gas at a low efficiency. Though it is possible to treat 100 or more wafers at one batch by utilizing the so-called low pressure CVD furnace, this furnace also provides a crystal insufficient in quality and allows the crystal to grow at a rate only on the order of 0.01 μm/minute, thereby being low in productivity.
As another method of growing a silicon crystal, there is known a liquid phase growing method of supersaturating a liquid metal solution in which silicon is dissolved and allowing a crystal to deposit from the solution onto a substrate. This liquid phase growing method is capable of growing a crystal of a high quality at a high rate on the order of 1 μm/minute and treating 100 or more wafers at one batch, thereby being suited to mass production. However, the liquid phase growing method is not generally used for growing silicon and has some technical problems to be solved though it widely prevails as a method of growing compound semiconductors.
One important problem lies in selection of a metal which is to be used as a solvent. It is desirable that a metal to be used for this purpose has a solubility for silicon which is as high as possible and can hardly be incorporated into deposited silicon. Furthermore, a metal having a lower melting point and a lower vapor pressure can be handled easier. Tin is used most generally as a solvent for silicon. Tin can be handled relatively easily since it has a low melting point and a relatively high solubility for silicon. It has been considered that tin is a preferable solvent since tin and silicon belong to Group IV of the periodic table, and tin is inactive as a dopant even when it is incorporated into deposited silicon.
However, the inventors have recently found that tin is incorporated into silicon in a relatively large amount when growth conditions (in particular, a growth temperature) are inadequate, thereby deforming a lattice of a silicon crystal and adversely affecting electric characteristics of a semiconductor probably due to the atomic size of tin which is very different from that of silicon though they are atoms belonging to Group IV. From this viewpoint, there is posed a doubt in the aptitude of tin as a solvent which is used to grow a crystal for a solar cell with high efficiency.
In addition to tin, elements such as gallium, indium and aluminum which belong to Group III can be mentioned as metals which are usable as solvents. Gallium and indium, in particular, having a low melting point can be handled easily. Since gallium is extremely expensive, indium is hopeful for use as a practical melt. However, indium posed a problem which is described later in control by introducing dopant a conductivity type of a silicon crystal which is grown using an indium melt. There are known examples wherein gallium is used as p-type dopant in combination with an indium melt (G. F. Zheng et al.: Solar Energy Materials and Solar Cells. 40 (1996) 231-238). Though gallium is usable at relatively low concentrations, it cannot be used for doping at high concentrations since a solid of gallium can be dissolved into silicon at concentrations within a relatively low solubility and is extremely expensive. On the other hand, examples which use n-type dopants in combination with indium melts are disclosed by Japanese Patent Application Laid-Open Nos. 9-183695 and 9-183696.
Boron and aluminum are generally used as p-type dopants, whereas phosphorus and arsenic are often used as n-type dopants. It is therefore conceivable to use these dopants for growing silicon crystals in liquid phase with the indium melt. In practice, however, problems were posed in conductivity types or reproducibility of conductivities of grown silicon crystals in certain cases. Furthermore, it is feared that a metal of Group III such as indium which is originally active by itself as a dopant may control a crystal to a strong p-type when incorporated into silicon and may be incapable of controlling it to p − -type or n-type.
The problems described above make it still impossible to judge whether or not the liquid phase method has a true aptitude for growth of silicon crystals on scales of mass production and whether or not solar cells utilizing thin films of silicon crystals have practical utility.
Thin films of silicon crystals are also used as devices for driving picture elements of liquid crystal displays and so on. Progress made in mass communication media have produced increasing demands for a display having a larger screen and capable of more minutely driving at a higher speed. Though the TFTs (thin film transistors) of amorphous silicon have hitherto been utilized as a driving circuit for picture elements to cope with the demands for a display having a larger screen, amorphous silicon can no longer meet the demands for a display which can be more minutely driven at a higher speed, and TFTs of polycrystalline silicon are coming into use. In addition, there has been increasing demand for polycrystalline silicon which has higher carrier mobility and other characteristics.
The liquid phase growing method is also suited for growing such crystalline silicon of a high quality on a large substrate such as a glass plate. Though use of a glass plate or the like makes it unallowable to heat a solution to a high temperature, it is possible to grow a crystal of a good quality by using indium as a solvent. Though it is impossible to grow a thick crystal at a low growth temperature which lowers a solubility of silicon into indium, there is no problem in formation of a crystal to be used as a TFT having a thickness of the order of 0.1 to 0.5 μm which is far smaller than that of a solar cell. When indium is used as a solvent for production of a TFT, a problem related to reproducibility may be posed. Therefore, a concentration of a dopant must be precisely controlled in order to enhance reproducibility of characteristics of the TFT. In formation of a film having a large area, an ununiform distribution of a dopant concentration is not preferable as it produces an ununiform distribution of characteristics of TFT, thereby producing variations in image density on a display device. In certain cases where indium was used as a dopant, it was impossible to sufficiently prevent the dopant from being distributed ununiformly on surfaces.
SUMMARY OF THE INVENTION
The present invention has been achieved in view of the current circumstances described above, and an object of the present invention is to provide a method of precisely controlling a dopant to be incorporated into crystalline silicon which is grown in a liquid phase using indium as a solvent, thereby enabling mass production of solar cells having a high efficiency and a light weight as well as driving circuits for a high precision and high speed display having a large area.
The present invention therefore provides a method of growing a silicon crystal, which comprises using a melt prepared by dissolving a solid of silicon containing a dopant at a predetermined concentration into liquid indium. Furthermore, the present invention provides a method of growing a silicon crystal, which comprises using a melt prepared by dissolving a solid of indium containing a dopant at a predetermined concentration into liquid indium.
Moreover, the present invention provides a method of producing a solar cell, which comprises the steps: preparing a melt by dissolving a solid of silicon containing a dopant at a predetermined concentration into liquid indium; forming a first silicon layer of a first conductivity type on a substrate by bringing the substrate into contact with the melt; and forming a second silicon layer of a second conductivity type on the first silicon layer of the first conductivity type.
In addition, the present invention provides a method of producing a solar cell, which comprises the steps of: preparing a melt by dissolving a solid of indium containing a dopant at a predetermined concentration into liquid indium and further dissolving silicon into the melt; forming a first silicon layer of a first conductivity type on a substrate by bringing the substrate into contact with the melt; and forming a second silicon layer of a second conductivity type on the first silicon layer of the first conductivity type.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view showing one example of a solar cell according to the present invention;
FIGS. 2A, 2 B and 2 C are sectional views showing one example of the production steps of a solar cell according to the present invention;
FIG. 3 is a sectional view showing one example of an apparatus used for carrying out a method of producing a silicon crystal according to the present invention;
FIG. 4 is a sectional view showing one example of an apparatus used for carrying out the method of producing a silicon crystal according to the present invention;
FIG. 5 is a sectional view showing one example of an apparatus used for carrying out the method of producing a silicon crystal according to the present invention; and
FIGS. 6A, 6 B, 6 C, 6 D, 6 E and 6 F are sectional views showing one example of the production steps of a thin film transistor (TFT) of polycrystalline silicon to which the method of the present invention is applied.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention has been achieved on the basis of knowledge obtained by experiments which are described below.
First, commercially available indium pellets were put into a carbon crucible, heated and melted at 1000° C. in a hydrogen gas flow to obtain liquid indium. A melt was prepared by bringing non-doped polycrystalline silicon into contact with the liquid indium and dissolving silicon into the liquid indium until it was saturated. Then, the melt was gradually cooled until it was supersaturated. When the melt was cooled to 980° C., a substrate of non-doped polycrystalline silicon was brought into contact with the melt, whereby a silicon crystal having a thickness of 10 μm was epitaxially grown on the substrate. A measurement of specific resistance of the silicon crystal by the four-probe method indicated approximately 0.2 Ωcm. Specific resistance was varied within a range from 0.1 to 0.5 Ωcm in similar experiments which were carried out using three different lots of commercially available indium as the melt.
A similar experiment was carried out using indium pellets refined to a high purity (6N), whereby a grown silicon layer on the substrate has an extremely high resistance (a difference in resistance between the grown silicon and the substrate could not be evaluated). By secondary ion mass spectrometry (SIMS) analysis of impurities contained in the grown silicon layer, no indium itself was unanticipatedly detected in any sample (below measurable limit). However, it was found that various kinds of impure elements such as gallium and aluminum of Group III in particular other than indium were contained in samples which were grown using commercially available indium. From this result, it is presumed that indium itself can hardly be incorporated into a siliconcrystal grown in a liquid phase, but the elements of Group III other than indium which were contained in the commercially available indium pellets were easily incorporated into the silicon crystals, thereby lowering resistance. In other words, it is necessary for precise control of conductivity of silicon to precisely control impurities, in particular, elements of Group III which are contained in indium.
Then, silicon was grown using a melt which was prepared by dissolving silicon into highly pure indium until it was saturated and then dissolving pellets of boron and aluminum. However, specific resistance of silicon grown as described above was low in reproducibility. The result of SIMS analysis indicated variations in concentrations of boron and aluminum in the silicon. Furthermore, silicon was grown using a melt which was prepared by dissolving silicon into highly pure indium until it was saturated, and then dissolving powders of phosphorus and arsenic. The silicon grown as described above was certainly of the n-type but its specific resistance was low in reproducibility. The result of SIMS analysis indicated variations in concentrations of phosphorus and arsenic in the silicon.
The inventors postulated a cause for these variations as described below. Since boron (density=2.23), aluminum (density=2.70), phosphorus (density=2.69) and arsenic (density=3.9) which are used as the dopants are significantly lighter than indium (density=7.28), a solution of such a dopant tends to be concentrated on a surface of an indium melt, whereby the indium solution as a whole is hardly uniform. Furthermore, solubilities of impurities which are subsequently dissolved into indium are very likely to be influenced by a concentration of silicon which has already been dissolved in the indium. In particular, when indium is nearly saturated with silicon, a slight variation in the saturation remarkably produces influences on the solubilities of the impurities, whereby the elements which are put into the melt as impurities are not always dissolved and concentrations of the elements of the impurities may be unstable in the melt.
It is possible to dissolve the elements of the impurities before dissolving silicon into indium by reversing the dissolving order. In this case, since pellets or powders of the impurities are to be put in trace amounts as compared with that of silicon, it is difficult to uniformly distribute the elements of the impurities in the melt as a whole.
For the reason described above, it is believed that indium makes it difficult to obtain a high degree of reproducibility of doping, though indium itself exhibits excellent properties as a melt in that it is hardly incorporated into silicon crystals and it facilitates obtaining high quality silicon crystals. The inventors therefore considered the possibility of diluting and then dissolving impurities into liquid indium. However, a diluent to be used for this purpose must be a substance which is hardly incorporated into grown silicon crystals or produces no adverse influence even when it is incorporated into the silicon crystals.
Indium can be used as a first example of an adequate diluent. An alloy prepared by dissolving impurities into indium at a predetermined concentration makes it possible to more accurately control concentrations of the impurities and prevent adverse influences from being produced by a diluent incorporated into silicon. Further, such an alloy is advantageous also from a viewpoint of having a slightly different density from that of a solvent, that is, liquid indium. When the diluted impurities are dissolved before dissolving silicon, it is possible to prevent the influence due to a concentration of silicon and use pellets or powders in large amounts, thereby uniformly dissolving the elements of the impurities into the melt.
Silicon can be used as a second example of an adequate diluent. When the elements of the impurities are preliminarily diluted with silicon, the elements of the impurities are always and simultaneously dissolved into indium with silicon, thereby facilitating the maintenance of constant concentrations of the elements relative to that of silicon.
The present invention which is based on the idea described above will be described in detail below with reference to effects and preferred embodiments thereof. However, the present invention is not limited to the following examples.
EXAMPLE 1
In Example 1, a solar cell having a structure shown in FIG. 1 was produced using a metal grade silicon substrate which had a low purity and was inexpensive due to the low purity.
What is meant by “metal grade silicon” is silicon which has a purity on the order of 99% and is obtained by metallurgically reducing silica. A substrate 101 of a metal grade polycrystalline silicon which was 0.1 mm thick and 4 inches in diameter was produced by dissolving a metal grade silicon nugget and gradually cooling it in a carbon die coated with silicon nitride. The substrate 101 contained boron at a high concentration and was of a strong p-type. Using a liquid phase growing apparatus which had a configuration shown in FIG. 3, a layer 102 of a p-type polycrystalline silicon was grown on the substrate 101 .
In the apparatus shown in FIG. 3, a crucible 301 made of quartz glass is filled with a dissolved indium melt 302 . The apparatus is accommodated as a whole in a quartz bell-jar 303 and heated to a desired temperature from outside with electric furnaces 304 . Hydrogen gas is always introduced into the quartz bell-jar 303 to maintain a reducing atmosphere in the bell-jar 303 . Further, a reference numeral 305 represents a substrate susceptor made of quartz glass which holds ends of a substrate 300 of a highly pure polycrystalline silicon or the substrate 101 of the metal grade polycrystalline silicon 101 having a diameter of 4 inches. The substrate 100 or 300 of the polycrystalline silicon is held obliquely so as to move smoothly into and out of the melt 302 . A reference numeral 306 designates a load lock chamber which can be partitioned from the quartz bell-jar 303 with a gate valve 307 . When setting silicon in the susceptor 305 or replacing silicon with another, the susceptor 305 is hoisted up with a hoist mechanism 308 , and the gate valve 307 is closed to prevent an interior of the quartz bell-jar 303 from being exposed to the atmosphere. A reference numeral 309 represents a dopant introducer which is configured also as a load lock mechanism and allows pellets 310 containing a dopant to be put into the indium melt 302 in a condition where the gate valve 307 is opened and the susceptor 305 is hoisted up.
Now, the method of growing the layer 102 of the p-type polycrystalline silicon will be described. First, the indium melt 302 was heated to 1000° C. and pellets 310 of highly pure indium containing 1% by weight of aluminum were put into the indium melt 302 . Since the indium pellets had a density which was nearly the same as that of indium, it was believed that the indium pellets were to uniformly disperse in the melt. Then, the substrate 300 of highly pure polycrystalline silicon was submerged as shown in FIG. 3 . The substrate 300 was maintained in this condition for 30 minutes to dissolve silicon into the indium melt 302 until it was saturated.
Then, the gate valve 307 was closed, the substrate 300 of the highly pure polycrystalline silicon was removed from the susceptor 305 , and a substrate 101 of metal grade polycrystalline silicon having the diameter of 4 inches was placed in the susceptor. After replacing an internal gas of the load lock chamber 306 first with nitrogen and then with hydrogen, the gate valve 307 was opened and the susceptor 305 was hoisted down to a preheating position (not shown in the drawings) over the melt 302 to wait for the temperature of the substrate 101 to rise. Thereafter, cooling of the interior of the quartz bell-jar was started at a rate of 1° C./minute. When the temperature reached 990° C., the substrate 101 was submerged into the melt 302 . Thirty minutes later, the susceptor 305 was hoisted up and the load lock chamber 306 was closed with the gate valve 307 . After replacing an internal gas of the load lock chamber 306 with nitrogen, the substrate 101 was taken outside. A p-type polycrystalline silicon layer 102 having a thickness of 30 μm had been grown on the substrate 101 .
A PSG layer (phosphor silicate glass layer) having a thickness of 200 Å was deposited on the surface of the p-type polycrystalline silicon layer 102 at a temperature of 560° C. using a CVD apparatus (not shown in the drawings). An n + -type silicon layer 103 was formed on the surface side by annealing the PSG layer in a nitrogen gas flow at a temperature of 1050° C. for 30 minutes and diffusing phosphorus (P). The remaining PSG was eliminated by etching with an aqueous solution of hydrofluoric acid. Furthermore, aluminum was deposited to a thickness of 2 μm on the surface of the n + -type silicon layer 103 by sputtering, and comb-teeth like grid electrodes 104 were formed by photolithography. Successively, a titanium oxide film having a thickness of 600 Å was deposited by sputtering as an anti-reflection film 105 . At this stage, pads of the grid electrodes 104 were masked to prevent titanium oxide from being deposited thereon. A solar cell produced as described above will hereinafter be referred to as a solar cell 1 .
The characteristic of the solar cell 1 was evaluated with an AM-1.5 solar simulator to obtain a photoelectric conversion efficiency of 13%. Furthermore, 21 subcells each having an area of 1 cm 2 were formed on the substrate 101 and checked for distribution of the photoelectric conversion efficiency. The result indicated a distribution within ±2% which was a favorable result. Moreover, a silicon crystal was grown successively five times while replenishing aluminum and silicon in the same procedures as those for the first growth in the amount of aluminum and silicon lost in each growth due to the deposition from the melt. This experiment indicated the variation of the photoelectric conversion efficiency within ±3% at one and the same location of each substrate, which was a favorable result.
As a comparative example, a solar cell 2 was produced in the same procedures as those for the solar cell 1 , except that pellets of pure aluminum were used as the pellets 310 containing the dopant. In this case, aluminum could hardly be incorporated into a p-type polycrystalline silicon layer 102 even when a dopant was replenished in a theoretically adequate amount. When the dopant was replenished in an amount exceeding the adequate amount, however, irregular spots were generated on the surface of the substrate 101 and the p-type polycrystalline silicon layer 102 , which were considered to be formed by reaction between silicon and aluminum. It is presumed that a layer of melted aluminum was formed on a surface of the melt and reacted with the substrate 101 or the silicon layer 102 . The solar cell 2 had remarkably ununiform photoelectric conversion efficiencies, and certain subcells exhibited no photoelectric conversion efficiencies at all. Thus, the effects of the present invention was clarified by this comparison.
EXAMPLE 2
Example 2 shows a principle of a method of producing a light-weight and highly efficient solar cell at a low cost by repeatedly using an expensive silicon wafer in steps shown in FIGS. 2A to 2 C. First, a porous layer 202 which was 5 μm thick was formed on a surface of a p + -type (100) single crystalline silicon wafer 201 having a diameter of 2 inches by so-called anodization which applies a positive voltage in hydrofluoric acid. The porous layer is composed of a large number of micropores which have a diameter of 100 Å which are formed by ununiformly dissolving silicon due to electrochemical action of hydrofluoric acid and which extend in a direction of a film thickness while complicatedly tangling with one another. It is possible to epitaxially grow a single crystalline silicon on this layer since a portion remaining as a skeleton maintains a property of a single crystal. Methods of forming a porous layer and application of the porous layer to solar cells are detailed by Japanese Patent Application Laid-Open Nos. 5-283722 and 7-302889.
FIG. 4 shows an apparatus for growing single crystalline silicon which was used in Example 2. Reference numerals 401 and 402 represent members which compose a carbon boat. The member 401 is provided with a cavity for dropping substrates 403 , 403 a and 403 b for dissolving and a cavity for dropping a substrate 404 for growing. The member 402 is provided with a hole in which an indium melt 405 is to be accommodated. The members 401 and 402 are configured to slide relative to each other.
A polycrystalline silicon substrate 403 for dissolving silicon into a melt and a single crystalline silicon substrate 404 having a porous layer 202 formed on the surface for growing a crystal were arranged in the member 401 . The member 402 was laid on the member 401 , and a predetermined amount of highly pure indium pellets were placed in the hole of the member 402 . When the indium pellets were heated in a hydrogen flow, they were melted into a melt 405 as shown in FIG. 4 . After maintaining the growing apparatus at 1050° C. for five minutes, the temperature was adjusted to 1000° C. and the melt 405 was brought into contact with the substrate 403 for dissolving by sliding the member 402 . As the substrate 403 for dissolving, a p-type polycrystalline silicon substrate doped with boron having specific resistance of 0.01 Ωcm was used. After keeping this state for one hour, cooling of the apparatus as a whole was started at a rate of 1° C./minute. When the temperature reached 980° C., the member 402 was slid to bring the melt 405 into contact with a surface of the porous layer 202 and cooled for one minute to form a p + -type silicon layer 203 having a thickness of approximately 1 μm. Thereafter, the melt was returned to its initial position by sliding the member 402 once again and left standing for cooling.
When the apparatus was cooled to room temperature, the hardened melt and the substrate 403 for dissolving were removed, whereafter highly pure indium pellets and the substrate 403 a for dissolving made of the p-type polycrystalline silicon doped with boron and having specific resistance of 1 Ωcm were newly arranged and heated in a manner similar to that at the preceding stage. After bringing the melt 405 into contact with the substrate 403 a for dissolving at a temperature of 1000° C., keeping it in this condition for one hour, cooling of the apparatus as a whole was started at a rate of 1° C./minute. When temperature was lowered to 980° C., the melt 405 was brought into contact with the surface of the p + -type silicon layer 203 by sliding the member 402 once again and cooled for thirty minutes, thereby forming a p-type silicon layer 204 which was approximately 30 μm thick. Then, the melt was returned to its initial position by sliding the member 402 once again and left standing for cooling.
When the melt was cooled to room temperature, the hardened melt and the substrate 403 a for dissolving were removed, whereafter highly pure indium pellets, and a substrate 403 a for dissolving made of n-type polycrystalline silicon doped with phosphorus and having specific resistance of 0.01 Ωcm were newly disposed and heated in a manner similar to that at the preceding stage. After bringing the melt 405 into contact with the substrate 403 b for dissolving at a temperature of 1000° C. and keeping it in this condition for one hour, cooling of the apparatus as a whole was started at a rate of 1° C./minute. When temperature was lowered to 980° C., the melt 405 was brought into contact with the surface of the p-type silicon layer 204 by sliding the member 402 and cooled for thirty seconds, thereby forming an n + -type silicon layer 205 which was approximately 0.5 μm thick. Thereafter, the melt was returned to its initial position by sliding the member 402 once again and left standing for cooling.
Furthermore, aluminum was deposited to form a 2 μm thick layer on the n + -type silicon layer 205 by sputtering while masking the layer 205 , thereby forming grid electrodes 206 . A titanium dioxide film 207 having a thickness of 600 Å and a magnesium fluoride film 208 having a thickness of 1000 Å were stacked as anti-reflection layers 207 and 208 by sputtering. In sputtering of the anti-reflection layers, grid tabs were masked so that the anti-reflection layers were not deposited thereon.
A transparent adhesive tape 209 was bonded to a surface of the anti-reflection layer thus formed. After a stacked body from the p + -type silicon layer 203 to the anti-reflection layer 208 was peeled from the silicon wafer 201 by destroying the porous layer 202 by applying forces in directions indicated by arrows in FIG. 2B, an aluminum sheet 210 was bonded to a back surface of the p + -type silicon layer 203 with an electroconductive adhesive, thereby forming a solar cell 3 .
The characteristic of the solar cell 3 was evaluated with an AM-1.5 solar simulator to obtain a photoelectric conversion efficiency of 18%. Furthermore, 26 subcells each having an area of 0.25 cm 2 were formed on a substrate 210 of an aluminum sheet and checked for a distribution of photoelectric conversion efficiencies. This result indicated a distribution within ±3%, which was a favorable result.
As a comparative example, a solar cell 4 was produced in the same procedures as in the case of the solar cell 3 , except that a melt was prepared by arranging powders of boron and phosphorus as dopants in the hole of the member 402 together with indium pellets and that a non-doped polycrystalline silicon was used as the silicon for dissolving. Possibly due to a fact that boron and phosphorus were not uniformly distributed in the melt in the liquid phase growth, photoelectric conversion efficiencies of the subcells were 10% at most and distributed within a broad range, and certain subcells exhibit no photoelectric conversion efficiency at all.
EXAMPLE 3
Example 3 shows steps for mass production of solar cells having a structure which is basically the same as that of the solar cell produced in Example 2 and proves that the method of the present invention is preferably applicable to mass production.
A porous layer 202 having a thickness of 2 μm was formed on each 6-inch silicon wafer 201 . In this case, the porous layers 202 could be formed on each of the wafers at the same time, and a working efficiency could be remarkably enhanced by connecting ten silicon wafers 210 in series in a solution of hydrofluoric acid and supplying a current to the wafers.
An apparatus for growing silicon crystal according to the present invention was based on the same principle as that of the apparatus adopted for Example 1 shown in FIG. 3, provided that a substrate susceptor 505 was used which is made of quartz glass and configured to be capable of accommodating ten substrates. Quartz glass crucibles 501 and quartz bell-jars (not shown in the drawings) are deepened correspondingly. The apparatus can be configured so as to accommodate a larger number of substrates to enhance production efficiency. Three quartz bell-jars having similar internal structures are connected to a common load lock chamber by way of gate valves so that substrates can move from one bell-jar into another without being exposed to the atmosphere.
First, a melt was prepared by placing highly pure indium pellets in a crucible 501 of a first quartz bell-jar, heating and melting the pellets at 1000° C. Highly pure indium pellets containing 1% by weight of aluminum were put into the melt, and then a polycrystalline silicon substrate for dissolving was submerged into the melt and kept in this condition for 30 minutes to dissolve silicon into the indium melt until it was saturated, thereby preparing a melt for growing a p + -type silicon layer.
Then, a melt was prepared by placing highly pure indium pellets in a crucible of a second quartz bell-jar, heating and melting the pellets at 1000° C. Then, ten substrates of polycrystalline silicon doped with boron and having a specific resistance of 0.05 Ωcm were attached to a susceptor 505 , submerged into the indium melt, kept in this condition for 30 minutes to dissolve silicon until the indium melt was saturated, thereby preparing a melt for growing a p-type silicon layer.
Further, a melt was prepared by placing highly pure indium pellets in a crucible of a third quartz ball-jar, heating and melting the pellets at 1000° C. Highly pure indium pellets containing 1% by weight of arsenic were put into the melt, and a polycrystalline silicon substrate for dissolving was submerged into the melt and kept in this condition for 30 minutes to dissolve silicon into the indium melt until it was saturated, thereby preparing a melt for growing an n + -type silicon layer.
With the gate valves kept closed, the polycrystalline silicon substrate for dissolving was removed from the susceptor 505 and a silicon wafer 201 (hereinafter simply referred to “substrate”) having a diameter of six inches and a porous layer 202 formed on a surface thereof was set in the susceptor. After replacing an internal gas of the load lock chamber first with nitrogen and then with hydrogen, the gate valve of the first quartz bell-jar was opened, the susceptor 505 was hoisted down to its preheating position, an interior of the quartz bell-jar was maintained at 1050° C. for ten minutes and then cooled to 1000° C., and gradual cooling of the interior of the quartz bell-jar was started at a rate of 0.2° C./minute. When the temperature reached 995° C., the substrate was submerged into the melt 502 as shown in FIG. 5 . After keeping this condition for ten minutes, the susceptor 505 was hoisted up. A p + -type silicon layer 203 having a thickness of approximately 2 μm was grown on the porous layer 202 . Since this apparatus treated a large number of substrates and required time for pulling the susceptor into and out of the melt, a crystalline silicon growing rate was set at a low level in order not to vary the thickness of the p + -type silicon layer 203 of each substrate.
After completely hoisting up the susceptor, the first quartz bell-jar was closed to maintain a hydrogen atmosphere in the load lock chamber, the gate valve of the second bell-jar was opened, the susceptor 505 was hoisted down to its preheating position and an interior of the bell-jar was maintained at 1000° C. for ten minutes. Then, gradual cooling of the interior of the quartz bell-jar was started at a rate of 1° C./minute. When the temperature reached 980° C., the substrate was submerged into the melt 502 as shown in FIG. 5 . After keeping this condition for 30 minutes, the susceptor 505 was hoisted up and the load lock chamber was closed. A p-type silicon layer 204 having a thickness of approximately 30 μm was grown on the p + -type silicon layer 203 .
While keeping the hydrogen atmosphere in the load lock chamber, the gate valve of the third quartz bell-jar was opened, the susceptor 505 was hoisted down to its preheating position, an interior of the quartz bell-jar was maintained at 1000° C. for ten minutes and then gradual cooling was started at a rate of 0.2° C./minute. When the temperature reached 995° C., the substrate was submerged into the melt 502 . After maintaining this condition for two minutes, the susceptor 505 was hoisted up and the load lock chamber was closed. An n + -type silicon layer 205 having a thickness of approximately 0.4 μm was grown on the p-type silicon layer 204 .
Thereafter, comb-like grid electrodes 206 were formed on the surface of the n + -type silicon layer 205 by printing a copper paste by the screen printing method and calcining the paste. Successively, a titanium dioxide film 207 having a thickness of 600 Å was formed by coating a metal alkoxide solution by the sol-gel method and calcining the solution, and a film ( 208 ) of silicon oxide 800 Å thick was formed in procedures similar to those used to obtain the two anti-reflection layers 207 and 208 . Ten or more substrates can easily be treated at a time by the screen printing method and the sol-gel method which are capable of treating a large number of substrates. These methods are preferable. Successively, an adhesive tape 209 was bonded to a surface of the anti-reflection layer, the layers of the p + -type silicon layer 203 from the upper layers were peeled from the substrate 201 by applying a force to the substrate 201 so as to destroy the porous layer 202 , and the tape 209 was peeled off with an organic solvent. Thereafter, a back surface of the p + -type silicon layer 203 was coated with an electroconductive ink, bonded to an aluminum support plate 210 and calcined for setting, thereby producing solar cells 5 .
Ten solar cells 5 were evaluated with an AM-1.5 solar simulator to obtain photoelectric conversion efficiencies of 17±0.3%, which were favorable and uniform. Furthermore, a solar cell module 1 was produced by connecting the ten solar cells in series and bonding them to a heat-resistant glass plate having a thickness of 3 mm with a PVC resin. This solar cell module 1 had an output of approximately 30 W.
Successively to the module 1 , a module 2 was produced in similar procedures. During the producing, the melts were not cooled but kept in melted conditions. However, the polycrystalline silicon substrate for dissolving was submerged again into the melt in each of the quartz bell-jars to dissolve silicon until the melt was saturated, since silicon concentration was lowered by deposition of a silicon crystal on the substrate. Boron was supplied together with silicon into the melt in the second quartz bell-jar. Since dopant concentrations were lowered in the melts in the first and third quartz bell-jars, pellets containing a predetermined amount of aluminum or arsenic were replenished into the melts in the first and third quartz bell-jars before replenishing silicon. The method of the present invention is capable of uniformly supplying a dopant with a high repeatability even when using a large crucible for mass production, whereby the module 2 also exhibited a characteristic equal to that of the module 1 .
As a comparative example, ten solar cells were produced at a batch by replenishing the melts with pellets or powders each containing a single element of aluminum, boron or phosphorus. These solar cells exhibited remarkably variable characteristics, and therefore a solar cell module 3 composed of these solar cells in series had an output characteristic of 5 W, illustrating that the method of the present invention is extremely excellent in mass production of modules connecting in series.
EXAMPLE 4
Example 4 shows an example that the method of the present invention was applied to the production of a thin film transistor (TFT) of polycrystalline silicon formed on a glass plate which was to be used in a driving circuit for a liquid crystal display device. FIGS. 6A to 6 F schematically show production steps. Stacked films of aluminum/chromium having a thickness of 2000 Å were deposited on a glass substrate 601 having a size of 4-inch square by sputtering. A pattern was formed as a gate electrode 602 on these films by photolithography (see FIG. 6 A). Using disilane and ammonia as raw material gases, a silicon nitride film having a thickness of 3000 Å was deposited as a gate insulating film 603 on the gate electrode 602 by the CVD method (see FIG. 6 B).
Used in Example 4 was a growing apparatus having a structure which was similar to that of the apparatus shown in FIG. 3 except that two quartz bell-jars were connected to a common load lock chamber by way of gate valves. First, an n-type polycrystalline silicon substrate doped with arsenic having a specific resistance of 0.5 Ωcm and a size of 4-inch square was submerged into an indium melt 302 in a crucible of a first quartz bell-jar as shown in FIG. 3 and maintained in this condition for thirty minutes to dissolve silicon into the melt 302 until it was saturated, thereby preparing a melt for an n-type silicon layer for dissolving. After indium pellets containing 2% by weight of boron were dropped in a predetermined amount into a highly pure indium melt in a second quartz bell-jar, a highly pure polycrystalline silicon substrate having a size of 4-inch square was dissolved thereto, thereby preparing a melt for a p + -type silicon layer for dissolving.
Then, the gate valve was closed, the polycrystalline silicon substrate was dismounted from a susceptor, and the glass substrate 601 on which the gate insulating film 603 had been formed was set in the susceptor. After an internal gas of the load lock chamber was replaced with nitrogen and then with hydrogen, the gate valve of the first quartz bell-jar was opened, and the susceptor was hoisted down to its preheating position and held at 600° C. for ten minutes to wait for the temperature of the substrate 601 to rise. Thereafter, gradual cooling of an interior of the quartz bell-jar was started at a rate of 0.2° C./minute. When the temperature reached 595° C., the substrate 601 was submerged into the melt. The substrate was maintained in this condition for 30 minutes until an n-type polycrystalline silicon layer 604 having a thickness of 3000 Å was grown on the gate insulating film 603 . Then, the susceptor was hoisted up, the gate valve was closed, the gate valve of the second quartz bell-jar was opened while maintaining the hydrogen atmosphere, and the susceptor was hoisted down to its preheating position and kept at 600° C. for ten minutes, whereafter gradual cooling of an interior of the quartz bell-jar was started at a rate of 0.2° C./minute. When the temperature reached 595° C., the substrate 601 was submerged in the melt and maintained in this condition for five minutes, whereby a p + -type silicon layer 605 having a thickness of 500 Å was grown on the n-type silicon layer 604 (see FIG. 6 C). Though silicon was grown at a very low rate in Example 4 due to the use of the glass substrate which did not allow the melt to be heated to a high temperature, the growth could be completed in a time within a range similar to that for the other examples since a necessary layer thickness was small.
After depositing stacked films of chromium/aluminum by sputtering, a source electrode 606 and a drain electrode 607 were patterned by photolithography (see FIG. 6 D). Using the electrodes 606 and 607 as masks, unnecessary portions of the p + -type layer at a channel portion 608 were removed by dry etching (see FIG. 6 E). Furthermore, a silicon oxide layer 609 was deposited on the surface by sputtering for surface protection (see FIG. 6 F).
In order to check the TFT for its basic characteristic, −5 V and 0 V were applied to the gate electrode while applying 5 V across the source and drain electrodes. This result indicated an on/off ratio of 10 6 . Moreover, a distribution of on/off ratios of 10 4 TFTs formed in the substrate was within an extremely narrow range of ±20%. Accordingly, it is possible to obtain display devices having a high contrast and free from ununiformity in colors by producing a driving circuit of TFTs according to the method of the present invention.
As a comparative example, a dopant was supplied as pellets or powders each singly composed of a dopant element. In this comparative example, on/off ratios of TFTs were distributed within a wide range of 10 2 , whereby the TFTs could not be expected to be usable for driving display devices.
As understood from the foregoing description, the method of the present invention is capable of growing high quality silicon crystals having a dopant concentration favorably controlled, thereby making it possible to produce high performance solar cells, driving circuits for liquid crystal display devices and so on at a low cost and with a high reproducibility. | A method of growing single crystal silicon in a liquid phase comprises preparing a melt by dissolving a solid of silicon containing boron, aluminum, phosphorus or arsenic at a predetermined concentration into indium melted in a carbon boat or a quartz crucible, supersaturating the melt, and submerging a substrate into the melt, thereby growing a silicon crystal containing a dopant element. This method can provide a method of growing a thin film of crystalline silicon having a high crystallinity and a dopant concentration favorably controlled, thereby serving for mass production of inexpensive solar cells which have high performance as well as image displays which have high contrast and are free from color ununiformity. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to a fixation device, particularly relates to a fixation device for communication equipments that is able to suck on a plane surface and adjust the horizontal angle, the vertical angle and the axial height. Thus, the communication equipments are placed in the most appropriate direction, height and angle.
[0003] 2. The Prior Arts
[0004] The recent communication equipments such as mobile phones, PDAs and GPS provide convenient communicating functions. Users may use the communication equipments anytime and anywhere. However, how to dispose the communication equipments when the users are taking the conveyance or using another tools at the same time is a big problem. Although the conventional fixation device for the communication equipments provides the function for fixing the communication equipments on the conveyance, but due to the frame of the communication equipments are fixed, the users may not do any adjustment on the fixation device. Therefore, the conventional fixation device is inconvenient to operate which is against the ergonomics and the habit.
SUMMARY OF THE INVENTION
[0005] A primary objective of the present invention is to provide a fixation device for the communication equipments, which is able to suck on a plane surface and adjust the horizontal angle, the vertical angle and the axial height. Therefore, the communication equipments are placed on the fixation device with the most appropriate direction, height and angle.
[0006] According to the primary objective described above, the present invention provides a fixation device comprising a base assembly, a horizontal rotating assembly pivoted to the base assembly, a first angle adjusting assembly pivoted to the horizontal rotating assembly and a second angle adjusting assembly pivoted to the first angle adjusting assembly. The base assembly includes a suction disk, a locking tab and a base. The suction disk includes a disk arm. The disk arm is disposed at the center thereof, telescoped into a base spring and then the base from the bottom of the base, and pivotally jointed to the locking tab by a positioning pin. The suction disk is sucked on the plane surface when the locking tab is in a first position, and the suction disk disengages from the plane surface when the locking tab is in a second position. In addition, the base has a base cap with a first toothed portion arranged in horizontal and circular on the top surface thereof. The horizontal rotating assembly is pivoted to the top of the base by a connecting bar and a connecting screw and rotates horizontally. The horizontal rotating assembly includes at least one elastic piece for engaging with the first toothed portion. The horizontal rotating assembly is fixed in place by the engagement between the elastic pieces and the first toothed portion when the horizontal rotating assembly rotates relative to the base assembly. The horizontal rotating assembly further includes two stop members respectively disposed at two opposite sides thereof and moved vertically. A first elastic member is telescoped fit on each stop member. When the stop members move, the first elastic members are deformed. When the stop members are released, the first elastic members push them back to their initial position. The first angle adjusting assembly is pivoted to the horizontal rotating assembly and rotates pivotally along an axis perpendicular to a central axis of the base assembly. Part of the first angle adjusting assembly is a cylindrical structure and the cylindrical axis is the rotation axis of the first angle adjusting assembly. The first angle adjusting assembly includes a second toothed portion arranged at the bottom surface thereof and engaged with the stop members when the first angle adjusting assembly connects with the horizontal rotating assembly. A second angle adjusting assembly is pivoted to the first angle adjusting assembly and rotates pivotally along an axis perpendicular to the rotation axis of the first angle adjusting assembly. The second angle adjusting assembly comprises a third toothed portion and connects to the first angle adjusting assembly by a second screw, a second elastic member and a positioning member. The second angle adjusting assembly is fixed in place when the positioning member engages with the third toothed portion. The second angle adjusting assembly is rotatable when the positioning member disengages from the third toothed portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present invention will be apparent to those skilled in the art by reading the following detailed description of a preferred embodiment thereof, with reference to the attached drawings, in which:
[0008] FIG. 1 is an assembly view showing a fixation device in accordance with the present invention;
[0009] FIG. 2 is an exploded view of the fixation device in accordance with the present invention;
[0010] FIG. 3 is a front cross-sectional view showing the fixation device in accordance with the present invention;
[0011] FIG. 4 is a side cross-sectional view showing the fixation device in accordance with the present invention;
[0012] FIG. 5 is an exploded view of a base assembly of the fixation device in accordance with the present invention;
[0013] FIG. 6A is a side view and a front cross-sectional view showing the base assembly of the fixation device in an initial condition in accordance with the present invention;
[0014] FIG. 6B is side view and a front cross-sectional view of the base assembly of the fixation device in an operational condition in accordance with the present invention;
[0015] FIG. 7A is an exploded view showing a horizontal rotating assembly in accordance with the present invention;
[0016] FIG. 7B is a schematic view showing a rotating direction of the horizontal rotating assembly in accordance with the present invention;
[0017] FIG. 8 is a top cross-sectional view showing the horizontal rotating assembly of the fixation device in accordance with the present invention;
[0018] FIG. 9 is an exploded view showing a connecting part and stop members of the fixation device in accordance with the present invention;
[0019] FIG. 10A is a schematic view showing a first angle adjusting assembly in rotating condition in accordance with the present invention;
[0020] FIG. 10B is a side cross-sectional view showing the first angle adjusting assembly in accordance with the present invention;
[0021] FIG. 11 is an exploded view showing a positioning member and a second crew of a second adjusting assembly in accordance with the present invention;
[0022] FIG. 12A is a side cross-sectional view showing the second angle adjusting assembly in accordance with the present invention; and
[0023] FIG. 12B is a front view showing the second angle adjusting assembly in rotating condition in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0024] Referring to FIG. 1 , a fixation device in accordance with an embodiment of the present invention comprises a base assembly 10 , a horizontal rotating assembly 20 pivoted to the base assembly 10 and rotating along an central axis of the base assembly 10 , a first angle adjusting assembly 30 pivoted to the horizontal rotating assembly 20 and rotating pivotally along an axis perpendicular to the axis of the base assembly 10 and a second angle adjusting assembly 40 pivoted to the first angle adjusting assembly 30 and rotated pivotally along an axis perpendicular to the rotation axis of the first angle adjusting assembly 30 .
[0025] With reference to FIGS. 2-4 , the base assembly 10 comprises a base 11 with a hollow supporting column 110 disposed at the center thereof and having a column recess 111 on a sidewall of the supporting column 110 . The base assembly 10 further comprises a base cap 12 having a base opening at a side surface and covering on the base 11 . A first toothed portion 120 is provided on the top surface of the base cap 12 and arranged in circularly and horizontal. The base assembly 10 further comprises a suction disk 13 made of a tenacious material. The suction disk 13 is provided with a disk arm 130 extended upward at the center of the suction disk 13 . Upper section of the disk arm 130 has a pinhole 131 . A base spring 14 is installed around the disk arm 130 . The base assembly 10 further comprises a positioning pin 16 and a locking tab 15 having two lugs 150 . Each of the lugs 150 has a lughole 151 and a projection 152 under the lug 150 . The disk arm 130 is installed into the supporting column 110 from the bottom of the base 11 through the base spring 14 . The positioning pin 16 pivotally joints with the supporting column 110 , the disk arm 130 and the locking tab 15 through the lugholes 151 , the column recess 111 and the pinhole 131 . When the suction disk 13 is placed on a plane surface and the locking tab 15 is flicked to a first position (flicked downward), the projections 152 is pressed on the base 11 and the disk arm 130 is raised upward by the lugs 150 . Accordingly, the suction disk 13 is sucked on the plane surface due to the negative pressure between the bottom of the suction disk 13 and the plane surface. Otherwise, the projections 152 disengage from the base 11 when the locking tab 15 is flicked to the second position (flicked upward). The disk arm 130 moves downward by the lugs 150 to release the suction disk 13 from the plane surface.
[0026] The horizontal rotating assembly 20 of the present invention comprises a rotating base 21 with two stop member connecting parts 210 , having two first elastic members 211 telescoped thereby. At least one elastic piece 26 is disposed on the bottom of the rotating base 21 . The horizontal rotating assembly 20 connects to the base cap 12 by inserting a connecting screw 25 into a connecting bar 24 , the rotating base 21 and then the top of the base cap 12 . A rotating cap 22 comprises a cap opening 224 at the center, two cap recesses 221 and two cap holes 220 , and connects with the rotating base 21 by a cap-fixing pin 222 . Two stop members 23 are telescoped to the stop member connecting parts 210 on the rotating base 21 by passing through the cap recesses 221 of the rotating cap 22 . The stop members 23 move along an axial direction of the rotating base 21 .
[0027] The first angle adjusting assembly 30 comprises a first angle adjusting base 31 having a second angle adjusting assembly recess 34 on the top surface thereof, a second toothed portion 310 on the bottom surface thereof, and a cavity 311 and a cavity 312 disposed on the opposite side thereof. The teeth of the second toothed portion 310 are arranged in a direction parallel to a rotation axis of the first angle adjusting assembly 30 . Two through holes 313 and 314 are arranged in the cavities 311 and 312 respectively. The first angle adjusting assembly 30 connects with the horizontal rotating assembly 20 by a connecting part 32 and a first screw 33 .
[0028] The second angle adjusting assembly 40 of the present invention comprises a second angle adjusting base 41 having a third toothed portion 410 disposed circularly on both side surfaces thereof and connects with the second angle adjusting assembly recess 34 of the first angle adjusting assembly 30 by a second screw 44 , a second elastic member 45 , and positioning members 42 and 43 .
[0029] As show in FIG. 5 , the positioning pin 16 connects the suction disk 13 , the base 11 and the locking tab 15 by passing through the lugholes 151 of the locking tab 15 , the column recess 111 on the supporting column 110 and the pin hole 131 on the disk arm 130 . The suction disk 13 is in contact with the ground when the locking tab 15 is in the second position (as show in FIG. 6A ). The suction disk 13 is disengaged from the surface plane. When the locking tab 15 is pressed to the first position (as show in FIG. 6B ), the projections 152 are pressed on the base 11 , the positioning pin 16 drives the disk arm 130 upward, and the disk arm 130 pull the center of the suction disk 13 upward. There is a negative pressure between the suction disk 13 and the plane surface. Thus the fixation device sucks on the plane surface.
[0030] As shown in FIG. 7A , the rotating base 21 connects to the base assembly 10 by the connecting bar 24 and the connecting screw 25 . As shown in FIGS. 7B and 8 , the horizontal rotating assembly 20 is rotatable along the central axis of the base assembly 10 after the rotating base 21 connects to the base assembly 10 . The elastic pieces 26 and the first toothed portion 120 are engaged thereby ensuring the horizontal rotating assembly 20 stops at the desired position.
[0031] As shown in FIG. 9 , the first angle adjusting assembly 30 connects with the horizontal adjusting assembly 20 by the connecting part 32 and the first screw 33 . The stop members 23 are disposed at a lateral surface of the horizontal rotating assembly 20 . The stop members 23 move along the axial direction of the rotating base 21 and are pushed back to an initial position by the first elastic members 211 when they are released. As shown in FIGS. 10A and 10B , the second toothed portion 310 disengages from the stop members 23 when the stop members 23 move downward to leave the initial position. Therefore, the angle of the first angle adjusting assembly 30 is adjustable. The stop members 23 engage with the second toothed portion 310 of the first angle adjusting base 31 when the first elastic members 211 push the stop member 23 back to the initial position. Thus, the angle of the first angle adjusting assembly 30 is fixed. Lower part of the first angle adjusting assembly 30 is a cylindrical structure. A cylindrical axis is the rotation axis of the first angle adjusting assembly 30 and is perpendicular to the central axis of the base assembly 10 .
[0032] As shown in FIGS. 11 , 12 A and 12 B, the second angle adjusting base 41 of the second angle adjusting assembly 40 is disposed in the second angle adjusting assembly recess 34 of the first angle adjusting assembly 30 by the second screw 44 , the second elastic member 45 and the positioning members 42 and 43 . The positioning member 42 moves outward with the second screw 44 when the positioning member 43 is pressed. The position member 42 disengages from the third toothed portion 410 . Therefore, the second angle adjusting assembly 40 is free to rotate as shown in FIG. 12B . The positioning member 42 is pushed back to its initial position and engaged with the third toothed portion 410 by the second elastic member 45 when the positioning member 43 is released. Lower part of the second angle adjusting assembly 40 is a cylindrical structure. A cylindrical axis is the rotation axis of the second angle adjusting assembly 40 and is perpendicular to the rotation axis of the first angle adjusting assembly 30 .
[0033] As mentioned, the fixation device described above with the communication equipments installed on the second angle adjusting assembly 40 is sucked on a surface by the suction disk 11 of the base assembly 10 . The rotation of the horizontal rotating assembly 20 , the first angle adjusting assembly 30 and the second angle adjusting assembly 40 achieves the purposes for user's ergonomics, habits and the convenient operation.
[0034] Although the present invention has been described with reference to the preferred embodiment thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims. | A fixation device includes a base assembly including a suction disk and a base; a horizontal rotating assembly pivoted to the base assembly and rotating pivotally along a central axis of the base assembly; a first angle adjusting assembly pivoted to the horizontal rotating assembly and rotating pivotally along an axis perpendicular to the central axis of the base assembly; and a second angle adjusting assembly pivoted to the first angle adjusting assembly and rotating pivotally along an axis perpendicular to the rotation axis of the first angle adjusting assembly. The suction disk includes a disk arm extending upward and the base has a supporting column extending upward. The supporting column and disk arm pivotally joint with a locking tab. By flicking the locking tab, the suction disk is capable of sucking on and disengaging from a plane surface. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. provisional Application Ser. No. 60/430,928, Filed Dec. 4, 2002, and is a § 371 of PCT/US03/038057.
FIELD OF THE INVENTION
[0002] This invention relates to catalysts useful in producing polyurethane foams. The invention also relates to processes for manufacturing polyurethane foams. A foam produced in accordance with the teachings of the present invention has a greatly reduced propensity towards emitting vapors of residual catalyst after it has cured while still retaining a high level of performance characteristics.
BACKGROUND
[0003] Molded foams prepared using conventional catalysts (fugitive amine catalysts) have been known for quite some time. However, with recent new concerns about the emission of volatile organics from finished foam products such as automotive interior parts like dashboards, seats, and trim, many foams made using prior art chemistry and processes are becoming unacceptable because of the emission of residual amounts of the amine catalysts used in their manufacture. One solution proposed by those skilled in the art has led to attempts to employ reactive catalysts, i.e., those which are chemically reacted during the curing process with the thought being that if the catalyst is reacted, then it is not possible for it to be emitted from the finished foam product. Unfortunately, thus far such attempts have resulted in foams having physical properties which are unacceptably low in performance terms for their intended use. Thus, finding catalysts which do not volatilize after a foam is in place in its final manufacture, which catalysts also produce foams having acceptable performance properties, is a currently problem at the forefront of the polyurethane foam art.
[0004] Huntsman's new non-reactive catalyst JEFFCAT® Z-140 helps to prevent losses in performance known to occur when reactive catalysts are used, and this catalyst and its use is described in the disclosure in U.S. Pat. No. 6,458,860. While JEFFCAT® Z-140 catalyst helps to minimize emissions from a cured foam, foams formed using the JEFFCAT® Z-140 catalyst may still not meet some of the newer emission requirements in the future, should such requirements become more stringent. Another patent document, U.S. Pat. No. 5,010,117 describes the use of polyols having low levels of unsaturation to improve the processing and compression set values of the foams so produced.
[0005] The present invention solves the problem of molded foams which require both low amine emission from the finished foam after curing, and a high performance level of physical properties. Such foams are required by the automotive industry.
SUMMARY OF THE INVENTION
[0006] We have surprisingly found that polyurethane foams prepared using polyols having a low level of unsaturation in the presence of reactive amine catalysts enables us to overcome the issue of the emission of residual amines from polyurethane foams, while still maintaining the satisfactory physical properties of the finished foams, such as wet and humid-aged compression set values.
[0007] The present invention provides a process for producing a polyurethane foam comprising the steps of: a) providing an organic polyol having a molecular weight in the range of 2000 to 7000, wherein the polyol has a level of unsaturation of between 0.001 and 0.030 meq./gram; b) providing an organic isocyanate; c) providing a blowing agent; d) providing a reactive catalyst; e) mixing the polyol, isocyanate, and the blowing agent in the presence of the catalyst, so as to produce a polyurethane foam.
DETAILED DESCRIPTION
[0008] The present invention comprises the manufacture of polyurethane foams using reactive catalysts and high molecular weight polyols that are possessed of very low levels of unsaturation as raw materials. A polyurethane foam prepared according to the present invention may includes all foams known, including: flexible foam, HR foam, semi-rigid foam, rigid foam, microcellular foam, and elastomer foams which are prepared by the conventional known one-shot method, or the pre-polymer method. Thus, the words “polyurethane foam” as used herein includes all of the aforesaid foam types. Among these known processes, particularly preferable is the process for producing polyurethane foam by using a foaming agent which is processed in a combined form such as foil, coating, or border material, or by molding integratedly, with other materials. These “other materials” include without limitation resins such as polyvinylchloride resin, ABS resin, polycarbonate resin, etc., metals, and glasses. Examples of applications of the final foam product include interior articles of automobiles such as instrument panels, seats, head rests, arm rests, and door panels as well as packaging materials.
[0009] Polyurethane foam is usually produced by a process which comprises the steps of: a) providing an organic polyol having a molecular weight in the range of 2000 to 7000 and a level of unsaturation of less than 0.10 meq./gram; b) providing an organic isocyanate; c) providing a blowing agent; d) providing a reactive catalyst; and e) mixing the polyol, the isocyanate, and the blowing agent in the presence of the catalyst, so as to produce a polyurethane foam. Various possible equipment configurations useful in conjunction with carrying out such steps to produce a foam are known in the art. Polyols useful in providing a polyurethane foam according to the present invention include polyetherpolyols, polymer polyols, and polyesterpolyols having 2 or more reactive hydroxyl groups. Polyetherpolyols include, for example, polyhydric alcohols such as glycol, glycerin, pentaerythritol, and sucrose; aliphatic amine compounds such as ammonia, and ethyleneamine; aromatic amine compounds such as toluene diamine, and diphenylmethane-4,4′-diamine; and/or a polyetherpolyol obtained by adding ethylene oxide or propylene oxide to a mixture of above-mentioned compounds. Polymer polyol is exemplified by a reaction product of said polyetherpolyol with ethylenic unsaturated monomer, such as butadiene, acrylonitrile, and styrene, the reaction being conducted in the presence of a radical polymerization catalyst. It is most preferable that a polyol used to prepare a foam according to the present invention has an unsaturation content of less than 0.03 meq./gram. According to an alternate form of the invention, the polyol used to prepare a foam according to the present invention has an unsaturation content of between 0.001 and 0.030 milliequivalents for every gram of polyol used in its manufacture. According to yet another alternate form of the invention, the polyol used to prepare a foam according to the present invention has an unsaturation content of between 0.005 and 0.025 milliequivalents for every gram of polyol used in its manufacture. According to yet another alternate form of the invention, the polyol used to prepare a foam according to the present invention has an unsaturation content of between 0.010 and 0.020 milliequivalents for every gram of polyol used in its manufacture. Thus, the words “organic polyol” as used herein includes any and all of the aforesaid polyols, including mixtures thereof.
[0010] As for the isocyanate or polyisocyanate component, all organic isocyanates or polyisocyanates known to those skilled in the art as being useful in preparing polyurethanes may be employed in a process according to the invention including, for example, aromatic polyisocyanates such as toluene diisocyanate, diphenylmethane-4,4′-diisocyanate, and positional isomers thereof, polymerized isocyanate thereof, and the like; aliphatic polyisocyanates such as hexamethylenediisocyanate and the like; alicyclic polyisocyanates such as isophoronediisocyanate and the like; pre-polymers with end isocyanate groups such as toluenediisocyanate pre-polymer and diphenylmethane-4,4′-diisocyanate pre-polymer which are obtained by the reaction of the above-mentioned substances with a polyol; denatured isocyanate such as carbodiimide denatured substances; and further mixed polyisocyanates thereof. Thus, the words “organic isocyanate” as used herein includes any and all of the aforesaid isocyanates, including mixtures thereof.
[0011] Blowing agents useful in accordance with the present invention are exemplified by low boiling point hydrocarbons such as butane, and pentane, halogenated hydrocarbons, carbon dioxide, acetone, and/or water. Known halogenated methanes and halogenated ethanes may be used as halogenated hydrocarbons. Among them, preferably, are chlorofluorocarbon compounds such as dichlorotrifluoroethane (R-123), dichloromonofluoroethane (R-141b), and the like. The amount of the foaming agent to be used is not particularly limited, but the amount of chlorofluorocarbon to be used is usually not larger than 35 parts by weight, preferably 0 to 30 parts by weight, based on 100 parts of polyol, and the amount of water to be used is not less than 2.0 parts, preferably 3.0 to 20.0 parts. Thus, the words “blowing agent” as used herein includes any and all of the aforesaid blowing agents, including mixtures thereof.
[0012] It is often the case that it is beneficial to include a foam stabilizer in the polyol portion of the polyurethane precursors. Such a stabilizer is selected, for example, from non-ionic surfactants such as organopolysiloxanepolyoxyalkylene copolymers, silicone-glycol copolymers, and the like, or a mixture thereof. Suitable silicone stabilizers include without limitation TEGOSTAB® B-4690 by Goldschmidt and DC-5043 by Dow Corning. The amount of the stabilizer is not particularly specified, but is usually about 0 to 2.5 parts by weight based on 100 parts by weight of polyol, as is known to those skilled in this art.
[0013] Reactive catalyst components useful as components in producing a foam according to the invention include, without limitation: JEFFCAT® DMEA, JEFFCAT® ZR-70, JEFFCAT® Z-110, JEFFCAT®ZF-10 (2-(2-(2-dimethylaminoethoxy-)ethyl methyl amino-)ethanol), JEFFCAT® ZR-50 (bis-(3-dimethylaminopropyl)-imino-propan-2-ol); JEFFCAT® DPA (2-propanol, (1,1′-((3-(dimethylamino)propyl)imino)bis-;), JEFFCAT® Z-130, (tetramethyliminobispropylamine), dimethylaminopropylurea, bis(dimethylaminopropyl)urea, or any material that is known to those skilled in the art as being capable of functioning as a blowing or gelling catalyst in a polyurethane system which contains three heteroatoms or active sights with two carbon spacing which is consumed during the formation of the foam. The most preferred catalysts are JEFFCAT®ZF-10, JEFFCAT® ZR-50, JEFFCAT® DPA, and JEFFCAT® Z-130. Thus, the words “reactive catalyst” as used herein includes any and all of the aforesaid catalysts, including mixtures thereof.
[0014] Non-reactive catalyst components useful as components in producing a foam include, without limitation: JEFFCAT® TAP, JEFFCAT® ZF-22, JEFFCAT® DD, tetramethylbutanediammine, dimorpholinodiethylether, JEFFCAT®MEM, JEFFCAT®MEM DM-70, JEFFCAT®MEM bis(dimethylaminoethoxy)ethane, JEFFCAT® NMM, JEFFCAT® NEM, JEFFCAT® PM, JEFFCAT® M-75, JEFFCAT® MM-20, JEFFCAT® MM-27, JEFFCAT® DM-22, Pentamethydiethylenetriamine, Tetramethylethylenediammine, Tertamethylaminopropylamide, 3-dimethylamino-N,N-dimethylpropylamide, or any material that is known to those skilled in the art as being capable of functioning as a blowing or gelling catalyst in a polyurethane system which is not consumed during the formation of the foam. Thus, the words “non-reactive catalyst” as used herein includes any and all of the aforesaid catalysts, including mixtures thereof. (JEFFCAT® is a registered trademark of Huntsman Petrochemical Corporation of Austin, Tex.) All of the foregoing JEFFCAT® trademarked materials are available from Huntsman Petrochemical Corporation, 7114 North Lamar Boulevard, Austin, Tex.
[0015] According to the present invention, other auxiliary agents may be added to the polyurethane precursors if necessary, and preferably to the polyol prior to its being contacted with the isocyanate. They include flame retardants, coloring agents, fillers, oxidation-inhibitors, ultraviolet ray screening agents, and the like known to those skilled in the art.
[0016] The amount of the amine catalyst used in a composition from which a foam may be produced in accordance with the present invention is in the range of from 0.02 to 10 parts, more preferably 0.1 to 5 parts, by weight based on 100 parts of the polyol. This includes any catalyst used. In addition, other known tertiary amine catalysts, organic carboxylic acid salts thereof, and organo tin compounds which are usually used as co-catalysts may be employed as auxiliary catalysts. In the process for producing polyurethane according to the present invention, polyols, polyisocyanates, and foaming agents, stabilizers, and if necessary, other auxiliary agents which are hitherto known, may be employed.
[0017] The Examples which follow are provided for the benefit of those skilled in the art to appreciate a working example of the principles embraced by the inventive concept. These examples are provided as being inseparably attached to the understanding that they are to be construed as exemplary, and not as delimitive of the invention in any way, shape, or form.
EXAMPLES
[0018] In the examples which follow, two polyols were used—Polyol A (an ethylene oxide capped—propylene oxide adduct of glycerine with a hydroxyl number of 32.7 mg KOH/g and an unsaturation content of 0.0419 meq./g); and Polyol B (an ethylene oxide capped—propylene oxide adduct of glycerine with a hydroxyl number of 31.5 mg KOH/g and an unsaturation content of 0.0241 meq./g). Thus, Polyol A has a higher level of unsaturation than Polyol B. The unsaturation of the polyol is determined using mercuric acetate titration, as is well-known to those skilled in the art. All parts and percentages set forth in the present specification and appended claims are expressed on a weight basis.
[0019] These foams also contain either reactive or non-reactive catalysts. The non-reactive catalyst system is a blend of JEFFCAT® TD-33A, JEFFCAT®ZF-22, and JEFFCAT® Z-150 dissolved in nonylphenol ethoxylate. The reactive catalyst system is a blend of JEFFCAT® ZF-10 and JEFFCAT® ZR-50.
[0020] The foams of Examples 1-3 were made by premixing the polyol components together, 648.9 g, with the specified amount of catalysts, and then adding the isocyanate, 205.4 g (the isocyanate used is a 90/10 weight ratio of toluene diisocyanate and Rubinate® M, a polymeric isocyanate), and mixing for 6 seconds using a 3000 ppm stirrer. The mixture was then poured into a cubic shaped, 15 by 15 by 4-inch mold, which mold was pre-heated to 54°-57° C. After filling, the mold was closed and placed in the oven at 66° C. for 6 minutes. The foam sample was removed from the hot mold and crushed to open the cells of the foam. The foam was then placed into an oven at 66° C. for thirty minutes. Formulation, molding conditions, and physical properties for these foams are shown in Table I below:
Example No. Component 1 2 3 Polyol A 75 75 — Polyol B — — 75 ARCOL ® 3428 25 25 25 Polymer Polyol Water 2.5 2.5 2.5 Diethanolamine 1.275 1.275 1.275 Silicon surfactant 1.00 1.00 1.00 JEFFCAT ® ZF-22 1 0.09 — — JEFFCAT ® TD-33A 2 0.30 — — Mixture of 33% (wt.) JEFFCAT ® 0.30 — — Z-150 3 and 67% (wt.) SURFONIC ® N-95 JEFFCAT ® ZF-10 — 0.10 0.10 JEFFCAT ® ZR-50 — 0.50 0.50 Index 1 1 1 TDI/Polymeric isocyanate 33.2 33.2 33.8 (90/10 wt %) Molding conditions Temperature (° C.) 54-57 54-57 54-57 Mold fill time, (sec.) 80 80 74 Post cure at 66° C. (min.) 30 30 30 Physical Properties Molded properties molded density (kg/cm 3 ) 50.2 49.8 49.7 core density (kg/cm 3 ) 46.4 44.4 44.6 Humid Aged (5 hrs. @ 125° C.) ASTM 3574 Compression Set, 50% 11.0 18.8 8.6 Wet set 4 16.7 30.7 16.8 1 70% (bisdimethylaminoethyl)ether and 30% dipropylene glycol 2 33% triethylenediamine in dipropylene glycol 3 (N,N-3-dimethylamino-)N′,N′-dimethylpropylamide 4 50% compression set 22 hours at 49° C. and 100% relative humidity
[0021] Generally speaking, the foam of Example 1 was prepared using non-reactive catalysts and a polyol having a high level of unsaturation. The foam of Example 2 was prepared using reactive catalysts and a polyol having a high level of unsaturation. It is clear that the resulting foam from Example 2 has poor humid-aged properties. The foam of Example 3 was prepared using reactive catalysts and a polyol having a low lever of unsaturation in the polyol. The humid aged compression sets and wet sets are much better than example 2, but more importantly, they are about as good as or better than example 1, which is considered as the control sample.
TABLE II Example No. Component 4 5 HYPERLITE ® E-851 10 10 Polyol A 90 — Polyol B — 90 JEFFOL ® F-443 3 3 water 3.75 3.75 Silicon Surfactant 0.5 0.5 JEFFCAT ® TD-33a 0.51 — JEFFCAT ® ZF-22 0.10 — JEFFCAT ® ZF-10 — 0.10 JEFFCAT ® ZR-50 — 0.60 Physical Properties Humid Aged (5 hrs. @ 125° C.) ASTM 3574 Wet set, as described for table I 18.8 12.1
The foams in examples 4 and 5 were made on a two component high pressure impingement foam machine made by Hi-Tech Engineering of Grand Rapids, Mich. The pressure on the A and B precursor components of the polyurethane foam were set at 2000 psi. The A and B temperatures were held around 30° C. The throughput of the machine was set at 400 grams/second, and the shot time was adjusted to fill a 15 by 15 by 4-inch mold, which was pre-heated to 50° C. After filling the mold, the mold was closed and stuck back in the oven at 54° C. for 5 minutes. The foam sample was removed from hot mold and crushed to open up the cells of the foam. A 15-gallon flush of the next material was made in-between the runs run to clean the lines of old material.
[0022] As can be seen from examples 4 and 5, the humid aged compression sets of the foam having reactive catalysts and polyols with low levels of unsaturation perform better than the standard foam made from non-reactive catalysts and standard polyols with higher unsaturation.
TABLE III Example No. Component 6 7 Polyol B 75 75 HYPERLITE ® E-851 25 25 Water 2.5 2.5 Diethanolamine 1.275 1.275 Silicon surfactant 1.00 1.00 JEFFCAT ® ZF-22 0.09 — JEFFCAT ® TD-33A 0.30 — Mixture of 33% JEFECAT ® Z-150 0.30 — and 67% SURFONIC ® N-95 JEFFCAT ® ZF-10 — 0.10 JEFFCAT ® ZR-50 — 0.50 Index 1 1 TDI/RUBINATE ® M (90/10 wt %) 33.51 33.51 Molding conditions Temperature (° C.) 54-57 54-57 Mold fill time, (sec.) 75 70 Post cure at 66° C. (min.) 30 30 Physical Properties Molded properties molded density (kg/cm 3 ) 49.9 50.4 core density (kg/cm 3 ) 45.9 45.0 Head space emission testing micro- of carbon per gram of foam amine components 23.32 0.1
[0023] Examples 6 and 7 illustrate the advantages of having reactive catalysts in the foams. In these two examples, Bayer's HYPERLITE® E-851 which has a hydroxyl number of 20 mg KOH/g was used as the polymer polyol in place of ARCOL® 3428. Gas chromatography analysis of the head space showed that the amount of amine emission coming out of the foam from the reactive catalysts is essentially zero, which is a remarkable reduction over non-reactive catalysts. The head space emission testing was performed by sealing one gram of finished foam in a 22 milliliter glass phial and heated to 120° C. for 300 minutes. The carbon content of a one milliliter volume of the headspace from this container is then subjected to analysis by gas chromatography.
[0024] A foamed polyurethane prepared in accordance with the present invention may be carried out at any temperature in the range of between about 0 and 150° C. A foamed polyurethane prepared in accordance with the present invention may be carried out at any pressure in the range of between about 0.10 mm HG to 3 atmospheres.
[0025] Consideration must be given to the fact that although this invention has been described and disclosed in relation to certain preferred embodiments, obvious equivalent modifications and alterations thereof will become apparent to one of ordinary skill in this art upon reading and understanding this specification and the claims appended hereto. Accordingly, the presently disclosed invention is intended to cover all such modifications and alterations, and is limited only by the scope of the claims which follow. | Provided herein are catalyst combinations and processes useful for producing polyurethane foam products which have a greatly lessened tendency to emit vapors of residual amounts of catalysts, after prolonged storage of the foams even at elevated temperatures. According to one form of the invention, a reactive catalyst is used in combination with a polyol precursor wherein the polyol precursor has an unsaturation level that is below about 0.030 meq./g. | 2 |
TECHNICAL FIELD
The present invention relates to elevators and, more particularly, to electronic safety detection systems for elevator doors.
BACKGROUND OF THE INVENTION
In elevator installations, many automatic sliding doors are equipped with safety systems designed to detect potential interference with the closing operation of the doors. Such safety systems typically include a plurality of signal emitter sources disposed on one door, and a plurality of signal receiver sources disposed on the other door. The signal emitters emit a curtain of signals across the threshold of the elevator door which are received by the signal receivers. When the curtain of signals is interrupted, the safety system communicates with a door controller in order to either stop the door closing operation and open the doors, or to maintain the doors in an opened position, depending on the current door position.
A doorway safety system is described in U.S. Pat. No. 4,029,176 (Mills) that utilizes acoustic wave transmitters and receivers to detect objects or persons within an area near the elevator doors. The system detects objects positioned between the doors and across the threshold, and extends the zone of detection into the entryway. The transmitters send out a signal at an angle into the entryway. When an obstruction enters the detection zone, the signal reflects from the obstruction and is detected by the receivers.
Another doorway safety system described in U.S. Pat. No, 5,886,307 (Full et al.) discloses a three-dimensional system for detecting objects across the threshold and in the entryway. The system projects a curtain of light beams across the threshold and illuminates the area directly in front of the entryway with three-dimensional detection beams. The system detects obstructions between the doors and across the threshold if an obstruction breaks one or more of the beams. In addition, if energy from the three-dimensional beams reflects off of an object in the entryway into the three-dimensional receivers, the obstruction is also detected.
The above-described system for three-dimensional detection has significant shortcomings. For example, while curtain-type detection systems require a “break” in one or more curtain beams to indicate an obstruction across a threshold, three-dimensional detection requires a “connect” to indicate an obstruction. This inverted logic for three-dimensional detection results in a sensitivity to external sources of energy that are not problematic in single-plane or curtain-type detection systems.
Systems that use light as the energy source for three-dimensional detection are subject to interference from a variety of external sources. For example, sources of light external to the detection system located near the elevator installation can inadvertently be picked up by the light sensors of the detection system. If the light from an external source is modulated similarly to that transmitted by the door safety system, it can be picked up and interpreted as indicative of an obstruction. Such external sources of light may include fluorescent lighting systems, emergency strobe lights, and emergency vehicle beacons.
External sources of impulse-type, electrical noise may also result in inadvertent obstruction signaling in three-dimensional door safety systems. Sources of this type of electrical noise include relay type elevator controllers, as well as electromechanical door operators.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved, three-dimensional door safety detection system for sliding doors.
It is another object of the present invention to provide a three-dimensional door safety detection system that is reliably operable in the presence of impulse-type electrical noise.
It is yet another object of the present invention to provide a three-dimensional door safety detection system that is reliably operable in the presence of external light sources, including sources that produce light energy having characteristics similar to the light energy produced by the detection system.
These objects and others are achieved by the present invention as described herein.
The present invention is directed to a three-dimensional door safety system for detecting objects or persons approaching or in a predetermined safety zone of open doors. A plurality of receivers or detectors are located on one door, and a plurality of emitters are located on the opposite door. The area directly in front of the closing doors is scanned for obstructions. The safety system detects objects in the entryway, while distinguishing from external energy that is not produced by the safety system. Generally, each beam produced by the energy emitters is sampled. The amplitude of each respective beam is stored. The amplitudes are each compared to a predetermined detection threshold level to determine the presence or absence of objects in the detection area.
The first embodiment of the present invention takes into account the transitory nature of interference energy, where the interference is present for a very short period, then becomes undetectable. In this embodiment, each three-dimensional beam is sampled multiple times per door scan frame. The value of the smallest amplitude sample acquired is compared with the detection threshold level to determine the presence or absence of objects in the three-dimensional detection area. This embodiment effectively ignores most impulse-type interference, such as electrical noise spikes, and light produced by strobe lamps.
A second embodiment of the present invention also accounts for the transitory nature of interference energy. In this case, however, the interference energy continues to be detectable beyond the high amplitude portion of the interference signal. In this embodiment, each three-dimensional beam is sampled multiple times per door scan frame. The value of each sample is stored for the respective beam. Detection energy, reflecting from an object in the three-dimensional detection area should present a generally constant, i.e., within a predetermined maximum variance range, amplitude from sample to sample, within a single scan frame, for any particular beam. If the samples for any particular beam do not present this constant signature, the energy for that beam is considered to be interference energy and is ignored. This embodiment improves the discrimination capability of the first embodiment by providing the ability to ignore interference energy that is continuously detectable but inconsistent in amplitude, such as the light produced by some fluorescent lighting systems.
A third embodiment of the present invention assigns an identifier to the emitted energy to provide the ability to reject interference energy that is both continuously detectable and consistent in amplitude. In this embodiment, each three-dimensional beam is sampled a single time per door scan frame while the transmitted energy is produced with unique, verifiable modulation, i.e., a modulation code, that can be validated by the detection receiver. If the modulation code is detected in the sampled beam, a signal is generated indicating the presence of an object. If the modulation code of the detected energy received for a particular beam is not verified by the receiver, the detected energy for that beam is ignored, as interference energy, regardless of its amplitude. This embodiment provides the ability to reject interference energy that cannot be rejected by the first and second embodiments because the interference energy is continuously detectable and relatively constant in amplitude, such as light produced by some fluorescent lighting systems.
Alternate embodiments of the present invention could use various combinations of the approaches described above with respect to the three preferred embodiments. By combining the various approaches, the ability to discriminate between target detection energy and interference energy from external sources is enhanced.
Because of the sensitivity to external sources of light and impulse noise introduced by the addition of three-dimensional detection capability to door safety systems, some prior art systems are rendered inoperable under various conditions. Such conditions include elevator installations that utilize relay-type controllers, fire alarm systems that utilize strobe lights, installations in the vicinity of emergency vehicle beacons (i.e., hospitals), and installations near fluorescent lighting systems. The present invention provides a system that is reliably operable in such environments and, thus, more safe and economically operable.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic, partial front view of a system according to the present invention.
FIG. 2 is a schematic, partial view of a component of the system according to FIG. 1 .
FIG. 3 is a schematic, partial plan view of a system according to FIG. 1 .
FIG. 4 is a schematic, partial plan view of a system according to FIG. 1 .
FIG. 5 is a schematic representation of a binary modulation code in accordance with the present invention.
FIG. 6 shows a graphical representation of the detection and threshold beam strength values for a plurality of detectors.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A system according to the preferred embodiments of the present invention door safety system ( 10 ) for opening and closing a doorway ( 12 ) of an elevator car ( 16 ) adjacent to a hallway ( 14 ) and walls ( 18 , 20 ) is shown in FIG. 1. A set of hallway doors ( 24 , 26 ) and a set of elevator car doors ( 28 , 30 ) are shown. Both sets of doors ( 24 , 26 , 28 , 30 ) slide open and closed together across a threshold ( 34 ) with the hallway doors ( 24 , 26 ) closing and opening slightly ahead and behind, respectively, of the elevator car doors ( 28 , 30 ). A safety detection system ( 38 ) is installed on the elevator car doors ( 28 , 30 ) adjacent to the hallway doors ( 24 , 26 ). The safety detection system ( 38 ) includes a transmitter stack ( 40 ) and a detector stack ( 42 ), each disposed on opposite sides of the doorway ( 12 ) and facing each other.
As shown in FIG. 2, each transmitter stack ( 40 ) includes a housing ( 46 ) and a transparent cover ( 48 ) for protecting a transmitter circuit board ( 50 ) and a transmitter lens board ( 52 ). The transmitter lens board ( 52 ) includes a plurality of three-dimensional transmitter lenses ( 56 ) and a plurality of curtain transmitter lenses ( 58 ). The transmitter circuit board ( 50 ) includes a plurality of transmitters or light emitting diodes (LEDs) ( 60 ) disposed adjacent to each lens ( 56 , 58 ) for emitting infrared light. A transmitter barrier ( 64 ) supports the housing ( 46 ) and partially blocks light for the three-dimensional transmitter lenses ( 56 ).
The detector stack ( 42 ) is structured as a mirror image of the transmitter stack ( 40 ). The detector stack ( 42 ) includes a detector stack housing ( 66 ) having a transparent detector stack cover ( 68 ) for protecting a detector circuit board ( 70 ) and a detector lens board ( 72 ). The detector lens board ( 72 ) includes a plurality of three-dimensional detector lenses ( 76 ) and a plurality of curtain detector lenses ( 78 ). The curtain detector lenses ( 78 ) are disposed directly across from the curtain transmitter lenses ( 56 ). The detector circuit board ( 70 ) includes a plurality of detectors or photodiodes ( 80 ) adjacent to each lens ( 76 , 78 ) for detecting reflected light. A detector barrier ( 84 ) supports the detector housing ( 66 ) and partially blocks light for the three-dimensional detector lenses ( 76 ).
The safety system ( 38 ) includes a controller ( 77 ) that provides and controls power to the stacks ( 40 , 42 ), sequences and controls the signals to the stacks ( 40 , 42 ), and communicates with a door controller ( 79 ).
The controller ( 77 ) contains data acquisition and data processing circuitry, including a power supply, analog to digital converter, and microprocessor. The microprocessor, e.g., the model 68HC11 from Motorola, or other such commercially available microprocessors, further includes programmable memory for defining a executable program to detect potential interference with the elevator doors.
In operation, the safety system ( 38 ) prevents the elevator car doors ( 28 , 30 ) from closing if an object or person is detected either across the threshold ( 34 ) or approaching the doorway ( 12 ). The curtain transmitter lenses ( 58 ) emit a signal across the threshold ( 34 ) to the curtain detector lenses ( 78 ). If the curtain signal is interrupted when the doors ( 28 , 30 ) are either open or closing, the safety system ( 38 ) communicates with the door controller ( 79 ) to either maintain the doors ( 28 , 30 ) open or reverse the closing operation, respectively.
The three-dimensional transmitter lenses ( 56 ) emit a three-dimensional signal at a predetermined angle outward into the hallway ( 14 ), as shown in FIG. 3 and FIG. 4 . The detectors ( 80 ) and the three-dimensional detector lenses ( 76 ) receive a signal emitted from the three-dimensional transmitter lenses ( 56 ) and reflected from an object at a predetermined angle. The intersection between the field of view ( 86 ) of the three-dimensional transmitter lenses ( 56 ) and the field of view ( 96 ) of the three-dimensional detector lenses ( 76 ) defines a detection zone ( 94 ). When an object or a person enters the detection zone ( 94 ), a signal from the three-dimensional transmitter lenses ( 56 ) hits the obstruction and is reflected into the three-dimensional detector lenses ( 76 ). When the three-dimensional detector lenses ( 76 ) receive a signal, the safety system ( 38 ) processes the received signal to determine if the signal represents the detection of an obstruction. If so, the safety system ( 38 ) communicates with the door controller ( 79 ) to either reverse the closing operation or maintain the doors ( 28 , 30 ) open.
During operation, the safety system ( 38 ) continuously scans the door opening and responds to any detected obstructions on a frame-by-frame basis. Each scanner frame consists of two phases: a data acquisition phase; and a data processing phase.
For the purposes of the following discussion, the term “beam” refers to the signal emitted from a curtain transmitter lens ( 58 ) or from a three-dimensional transmitter lens ( 56 ).
In the data acquisition phase, each curtain and three-dimensional beam is sampled, and the resulting beam data is stored. Curtain beams are sampled only once per scan frame while three-dimensional beams may be sampled more than once per frame, as required by specific embodiment of the present invention. A single sample of any particular beam, whether curtain or three-dimensional, is completed in a maximum time period of 750 μSec.
In the data processing phase, the beam data, accumulated during the data acquisition phase, is processed to determine if an obstruction has been detected. Signals are sent to the door controller ( 79 ) indicating the presence or absence of door obstructions.
An individual beam is sampled in the following manner. First, the transmitter for the beam is activated. The emitted energy signal is modulated, to enable the detection circuitry to reject light from external sources (such as sunlight or light from incandescent bulbs). The type of modulation used is determined by the specific embodiment of the present invention. After the transmitter for the beam has been activated, the receiver for the beam is enabled to receive the transmitted signal. Any detected signal, is processed through various circuits (gain selection, filtering and rectification). The resulting signal is sent to an integrator stage. The integrator output starts at a reference voltage and ramps in the negative direction. The integrator output signal is then sent to a voltage comparator stage, where it is compared to a fixed hardware threshold voltage. When the integrator output ramps below the hardware threshold voltage, the comparator produces an “end-of-integration” signal. The time, from the start of integration to the “end-of-integration” signal, is a direct representation of the strength of the received beam signal. Shorter integration times indicate stronger detected beam signals. This time (or strength) value is then stored for the beam being sampled. If an end-of-integration signal is not produced within the 750 μSec maximum sampling time, a “no-detect” condition is determined for the beam being sampled.
The data processing phase essentially consists as illustrated in FIG. 6, of comparing the beam strength values 101 , 102 , 103 , accumulated during the data acquisition phase, to a predetermined detection threshold value 110 . If the detected signal for any three-dimensional beam 102 exceeds the threshold value 110 , a signal is sent to the door controller ( 79 ), indicating the detection of an obstruction.
In the first embodiment of the present invention, the transmitted beam signals are modulated with a continuous stream of square waves at a fixed frequency and each three-dimensional beam is sampled multiple times in each scan frame. Only the value for sample containing the smallest beam strength value is actually stored for any particular beam. Normal data processing takes place as previously described. The interference rejection provided by this embodiment is essentially provided entirely during the data acquisition phase of a scan frame, making this the simplest and fastest embodiment of the three discussed in this document.
In the second embodiment of the present invention, as in the first embodiment, the transmitted beam signals are modulated with a continuous stream of square waves at a fixed frequency and each three-dimensional beam is sampled multiple times in each scan frame. Unlike the first embodiment, the beam strength value for each sample is stored for each respective beam. During the data processing phase, the beam strength for each individual beam is validated, by comparing the strength values from each sample for that beam. Generally constant beam strength values, i.e., values within a predetermined maximum variance range, indicate valid beam signal reception, while significant variation between samples is indicative of the presence of interference energy. If the samples taken for a particular beam indicate the presence of interference energy, the signal received for that particular beam is ignored. However, if the samples taken for that beam indicated valid beam signal reception, and the smallest beam strength value is greater than the detection threshold, obstruction detection is indicated. The data for each three-dimensional beam is processed in like manner.
In the third embodiment of the present invention, the transmitted beam signals are modulated with a specific, repeating, binary code, at a fixed bit rate, rather than a simple square wave modulation. Referring to FIG. 5, an exemplary embodiment of a binary modulation code, as compared to a continuous square wave modulation, is illustrated. Each three-dimensional beam is sampled only once per scan frame. During the data acquisition phase, while the strength of any individual beam is being sampled, the binary modulation code of the received signal is verified, by monitoring the polarity of the received signal with a port pin of the CPU (central processing unit). If the binary modulation code is not verified, the detected signal is determined to be from a source external to the system and a “no-detect” level is stored for that beam. If the beam signal does contain the correct modulation code, a value representing its beam strength is stored for that beam, as previously described. The data processing phase takes place normally, as previously described. Even though a binary modulation code is described in the specification, it will be apparent to one skilled in the art that other modulation codes may also be used, e.g., a frequency modulated code.
Because of the sensitivity to external sources of light and impulse noise introduced by the addition of three-dimensional detection capability to door safety systems, some systems are rendered inoperable under various conditions. Such conditions include elevator installations that utilize relay-type controllers, fire alarm systems that utilize strobe lights, installations in the vicinity of emergency vehicle beacons (i.e., hospitals), and installations near fluorescent lighting systems. The present invention provides a system that is reliably operable in such environments and, thus, more safe and economically operable.
While the preferred embodiments of the invention have been herein described, it is understood that modification and variation may be made without departing from the scope of the presently claimed invention. | A system and an associated method of detecting an object in a three-dimensional field adjacent to a doorway, such as an elevator doorway, uses an array of energy emitters that emit three-dimensional energy signals into the field and an array of energy receivers that receive the energy signals reflected from the object. The signals are sampled a predetermined number of times. In one embodiment, if the lowest value sampled signal reaches a predetermined threshold, an object detection signal is generated. In an alternative embodiment, if the sampled signals are within a predetermined variance range, the object detection signal is generated. In another alternative embodiment, if a predetermined modulation code is detected within a sampled signal, the object detection signal is generated. | 4 |
[0001] This application claims priority from European Patent Application No. 12192033.4 filed Sep. 11, 2012, the entire disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention concerns a method of manufacturing a display device using organic light emitting diodes known as OLEDs. The present invention also concerns a display device with light emitting diodes obtained by implementing this method, in addition to a timepiece comprising a display device of this type.
BACKGROUND OF THE INVENTION
[0003] The present invention concerns OLED display devices. More specifically, the present invention concerns display devices known as passive matrix organic light emitting diodes or PMOLEDs. In PMOLED display devices, lighting is controlled by means of anodes and cathodes which are disposed in strips perpendicular to each other and powered separately. Although less energy efficient than active matrix light emitting diodes, also known as AMOLEDs, PMOLED display devices are less complex to make than AMOLED display devices and consequently were the first to be mass marketed.
[0004] Compared to other types of display devices such as liquid crystal cells, OLED display devices have very interesting advantages such as a very rapid response time, improved colour rendering, better contrast or even less directive emissivity, thus offering a broader angle of vision. Compared to liquid crystal display devices, another decisive advantage of OLED display devices is that they do not require backlighting. However, one drawback of OLED display devices is their sensitivity to air and moisture.
[0005] Very succinctly summarised, a PMOLED display device includes a base substrate, for example made of glass, on which anodes are structured in parallel strips. These anodes are made of a transparent, electrically conductive material such as indium tin oxide also known as ITO. After the indium tin oxide layer has been deposited on the glass substrate and the anodes have been structured, there is deposited in succession an insulating layer, whose purpose is to separate the line electrodes and column electrodes from each other, and a separation layer whose role is to create a space between the anodes and the cathodes to be deposited. The actual active layers, of which there are three, are then deposited: a hole injection layer, a hole transport layer and an electron transport layer. Finally, a layer of conductive material such as aluminium is deposited, in which the cathodes are structured. The resulting structure is covered with a cover which is bonded onto the edge of the base substrate. A moisture trap may be arranged in the volume left vacant by the cover.
[0006] As mentioned above, OLED display devices have a certain number of very interesting advantages for use, for example, in portable electronic objects, such as wristwatches. However, in the particular field of horology, those skilled in the art have been confronted by a problem, which, to the Applicant's knowledge, has not yet been resolved. This problem is connected to the combined use, in a timepiece, of a digital OLED display device and an analogue display device which conventionally includes a set of hour and minute hands. Indeed, in that case, the OLED display device is on the watch dial and the hour and minute hands move above the OLED display device. The hour and minute hands are carried by a set of concentric arbours which must necessarily pass through the OLED display device. However, since the active layers and the cathode layer of an OLED display device are very sensitive to air and moisture, it is not possible to envisage piercing the OLED display device for the arbours carrying the hour and minute hands to pass therethrough, since this would place the moisture-sensitive layers of the OLED display device in direct contact with the atmosphere.
SUMMARY OF THE INVENTION
[0007] Consequently, it is an object of the present invention to provide an OLED display device in which a hole may be made for the arbours carrying the hour and minute hands to pass through.
[0008] The present invention therefore concerns a light emitting diode display device, said display device including a substrate covered by a cover which has a plane surface delimited along the external perimeter thereof by an edge, via which the cover is secured to the substrate, the plane surface of the cover being provided with an outgrowth or protuberance which extends in the direction of the substrate, the substrate being provided with a stack of layers, said stack of layers comprising at least the following layers which succeed each other in the following order starting from the substrate:
[0009] at least one anode layer;
[0010] an insulating coating;
[0011] a spacer layer which has a first exclusion area in a first area which is located plumb with the protuberance;
[0012] an active hole injection layer;
[0013] an active hole transport layer;
[0014] an active electron transport layer;
[0015] a cathode which has a second exclusion area in a second area which is located plumb with the protuberance;
[0016] the protuberance of the cover being joined to the layer with which the protuberance is in contact, a hole, whose diameter is smaller than the geometrical dimensions of the protuberance, being made in the protuberance, and said hole also passing through the substrate.
[0017] As a result of these features, the present invention provides an OLED type display device which can be completely traversed by a hole through which, in the preferred example embodiment of the invention, a set of concentric arbours respectively carrying an hour hand and a minute hand are intended to pass. In fact, the protuberance of the cover, in which the hole is made for the hour and minute hand arbours to pass through, is totally sealed against moisture and oxygen, so that the active layers and the cathode layer of the OLED display device according to the invention are not liable to be damaged. To achieve this result, the present invention teaches providing an exclusion area in the spacer layer and in the cathode layer plumb with the protuberance of the cover. In other words, at the location of these exclusion areas, the materials used to deposit the spacer layer and the cathode layer are omitted. Indeed, after performing several tests, it was realised that if the spacer layer and the cathode layer remain at the place where the protuberance of the cover comes into contact with the active layers of the OLED display device, these cathode and spacer layers experience delamination when the hole is made in the protuberance of the cover, which results in the irreversible destruction of the OLED display device. Finally, it was noted that the quality of the bond between the protuberance and the substrate is much higher when the cathode and spacer layers are not present.
[0018] The present invention also concerns a method of manufacturing an OLED display device, said method including the steps consisting in:
[0019] taking a substrate and a cover which has a plane surface delimited along the external periphery thereof by an edge, via which the cover is intended to be secured to the substrate, the plane surface of the cover being provided with a protuberance, which extends in the direction of the substrate;
[0020] depositing in succession on the substrate at least one anode layer and an insulating coating;
[0021] then depositing a spacer layer in which a first exclusion area is arranged in a first area which will be located plumb with the protuberance of the cover once the cover is secured to the substrate;
[0022] depositing an active hole injection layer, an active hole transport layer and an active electron transport layer in that order;
[0023] depositing a cathode layer in which a second exclusion area is arranged in a second area which will be plumb with the protuberance of the cover once the cover is secured to the substrate, and
[0024] joining the cover to the substrate, then making a hole, whose diameter is smaller than the geometrical dimensions of the protuberance, in the protuberance of the cover and in the substrate.
[0025] According to a complementary feature of the method of the invention, the spacer layer, respectively the cathode layer, is deposited in two successive steps by means of a first mask, in which there is arranged a first aperture corresponding to a first portion of the spacer layer, respectively of the cathode layer, to be deposited, said first mask at least partially concealing an area of the substrate so as to form, in the spacer layer, respectively in the cathode layer, an exclusion area, which will be plumb with the protuberance once the cover is secured to the substrate; and by means of a second mask, which has a second aperture corresponding to a second portion of the spacer layer, respectively of the cathode layer, to be deposited, said second mask concealing if necessary the remainder of the area of the substrate, so as to form in the spacer layer, respectively in the cathode layer, the rest of the exclusion area which will be located plumb with the protuberance once the cover is secured to the substrate, the second aperture of the second mask being complementary to the first aperture of the first mask so that the combination of the first aperture and the second aperture corresponds to the desired spacer layer, respectively the cathode layer.
[0026] The present invention also concerns a timepiece comprising a light emitting diode display device in which a hole is made for an hour hand arbour and a minute hand arbour to pass through.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Other features and advantages of the present invention will appear more clearly from the following detailed description of one embodiment of an OLED display device according to the invention, this example being given solely by way of non-limiting illustration with reference to the annexed drawing, in which:
[0028] FIG. 1A is a perspective view of a glass substrate on which a conductive indium tin oxide layer and a chromium layer have been deposited in succession.
[0029] FIG. 1B is a similar view to that of FIG. 1A , showing the step of structuring the chromium layer.
[0030] FIG. 1C illustrates the step of structuring the conductive indium tin oxide layer.
[0031] FIG. 1D illustrates the deposition of an insulating layer.
[0032] FIG. 1E illustrates the structuring of the insulating layer so as to delimit the matrix display pixels.
[0033] FIG. 1F illustrates the deposition of the separation layer.
[0034] FIG. 1G illustrates the structuring of the separation layer.
[0035] FIGS. 1H , 1 I and 1 J respectively illustrate the deposition of the active hole injection, hole transport and electron transport layers.
[0036] FIG. 1K illustrates the deposition of the cathode layer.
[0037] FIG. 2 is a cross-section of an organic light emitting diode display device according to the invention.
[0038] FIG. 3 is a schematic view of a wristwatch fitted with an OLED display device according to the invention.
[0039] FIGS. 4A , 4 B and 4 C are top views of the first and second masks used for the vapour deposition of the spacer layer and of the cathode layer.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] The present invention proceeds from the general inventive idea which consists in providing an organic light emitting diode display device in which it is possible to make a hole for the arbours of hour and minute hands, for example, to pass through. It is known that it is impossible to make a hole straight into an OLED display device since this would place the active layers of the OLED display device in contact with the atmosphere and destroy them. To overcome this problem, the present invention teaches arranging an exclusion area in the spacer layer and in the cathode layer deposited on the substrate of the organic light emitting display device. In other words, at the location of these exclusion areas, the materials used to deposit the spacer layer and the cathode layer are omitted. The exclusion areas are located plumb with an protuberance provided in the bottom face of a cover which will cover the OLED display device at the end of manufacture. The hole for the arbours of the hour and minute hands is made in the protuberance and in the cover. This operation is made possible by the absence of the spacer layer and the cathode layer at the place where the protuberance comes into contact with the substrate. It was in fact realised that when the spacer layer and the cathode layer are present, these layers are subject to delamination when the hole is made in the protuberance of the cover. Further, the adhesion of the protuberance to the substrate is much better when the spacer and cathode layers are omitted. Having reached the conclusion that the spacer and cathode layers had to be omitted from the protuberance area, a method had to be found for depositing these layers in the desired manner. For this purpose, the present invention teaches depositing the spacer layer, respectively the cathode layer, in two successive steps, using two distinct masks, the first of which comprises a first aperture corresponding to a first portion of the spacer layer, respectively of the cathode layer, to be deposited, said first mask concealing all or part of the area of the substrate where it is desired to create the exclusion area; and the second of which comprises a second aperture which is the complement of the first aperture arranged in the first mask and which, if necessary, conceals the rest of the area of the substrate where it is desired to create the exclusion area. Finally, the invention concerns a portable object, such as a timepiece, comprising a light emitting diode display device in which a hole is made for an hour hand arbour and a minute hand arbour to pass through.
[0041] The various steps of the method for making a light emitting diode display device or OLED display device according to the invention are described below.
[0042] FIG. 1A is a perspective view of a substrate 1 , for example made of glass, on the surface of which a first conductive layer 2 and a second conductive layer 4 have been deposited in succession. The first conductive layer 2 is for example made of indium tin oxide, better known as ITO, and the second conductive layer 4 is for example made of chromium.
[0043] In FIG. 1B , the second conductive layer 4 has been practically removed from the entire surface by photolithography and chemical etching. Chromium remains only on contact pads 6 where the presence of this material improves electrical conduction.
[0044] FIG. 1C illustrates the step of structuring anodes 8 . These anodes 8 take the form of parallel strips and are obtained by photolithography and chemical etching of the first conductive ITO layer 2 .
[0045] FIG. 1D illustrates the step of depositing an insulating layer 10 over ITO anodes 8 . As seen upon examining FIG. 1E , insulating layer 10 is structured in lines 12 and columns 14 so as to delimit conductive areas 16 which will form the display pixels of the OLED display device of the invention.
[0046] In FIG. 1F , a layer of spacer material 18 is deposited in uniform thickness over substrate 1 . The function of this layer of spacer material 18 is to separate anodes 8 from the cathode which will be structured in a subsequent step of the method. It is seen that, substantially at the centre of substrate 1 , the spacer material has not been deposited so as to create an exclusion area 20 located plumb with an outgrowth or protuberance provided in the bottom face of a cover which, as will be seen in detail below, will cover the OLED display device of the invention at the end of manufacture.
[0047] In FIG. 1G , the spacer layer has been structured to form spacers 22 , which, in the example shown in the drawing, extend parallel to each other in a generally perpendicular direction to anodes 8 .
[0048] In FIGS. 1H , 1 I and 1 J, the active layers of the OLED display device of the invention are deposited one after the other, namely a hole injection layer 24 , a hole transport layer 26 and an electron transport layer 28 . These three layers 24 , 26 and 28 are deposited in a non-selective manner over the entire surface of substrate 1 .
[0049] Finally, as shown in FIG. 1K , a layer 30 which will form the cathode of the OLED display device of the invention, is deposited on substrate 1 . This cathode layer 30 is obtained by evaporating an electrically conductive material, such as, in a non limiting manner, aluminium. It may also be a mixture of aluminium and calcium or a barium and silver alloy. It is seen that, substantially at the centre of substrate 1 , cathode material 30 has not been deposited so as to create an exclusion area 32 located plumb with an outgrowth or protuberance 32 provided in the bottom face of a cover which, as will be seen in detail below, will cover the OLED display device of the invention at the end of manufacture.
[0050] Reference will now be made to FIG. 2 which is a cross-section of an organic light emitting diode display device according to the invention. Designed as a whole by the general reference numeral 34 , the OLED display device of the invention includes substrate 1 over which the indium tin oxide or ITO anode layer 8 , insulating layer 10 and spacer layer 18 have been deposited in succession. According to the invention, this layer of spacer material 18 is omitted at the place where exclusion area 20 is located. It will be recalled that exclusion area 20 is located plumb with an outgrowth or protuberance 36 , which extends in the direction of substrate 1 and which is arranged in the plane surface 38 of a cover 40 which covers OLED display device 34 of the invention at the end of manufacture.
[0051] The method of manufacturing OLED display device 34 of the invention continues with the non-selective deposition of the active layers of the OLED display device of the invention, namely a hole injection layer 24 , a hole transport layer 26 and an electron transport layer 28 . The manufacturing method ends with the deposition of cathode layer 30 . According to the invention, this cathode layer 30 is omitted from the place where exclusion area 32 is located. It will be recalled that exclusion area 32 is located plumb with protuberance 36 which is arranged in the plane surface 38 of cover 40 which will cover OLED display device 34 of the invention at the end of manufacture.
[0052] Finally, OLED display device 34 is hermetically sealed by means of cover 40 . Cover 40 has an edge 42 , along the external periphery of the plane surface 38 thereof, via which cover 40 is secured, by means of an adhesive film 44 , to substrate 1 . Protuberance 36 , arranged in plane surface 38 of cover 40 , extends in the direction of substrate 1 in the area where exclusion areas 20 and 32 are arranged in spacer layer 18 and cathode layer 30 . Consequently, protuberance 36 is in virtually direct contact with substrate 1 , only separated therefrom by anode layer 8 and by active layers 24 , 26 and 28 , which are very thin. A thin adhesive film 46 enables protuberance 36 to be bonded to substrate 1 .
[0053] According to the invention, a hole 48 , whose diameter is smaller than the geometrical dimensions of protuberance 36 , is made in protuberance 36 . Hole 48 also traverses substrate 1 . As a result of this feature, the present invention provides an OLED display device in which a through hole is made without placing the active layers and the cathode layer in contact with moisture and oxygen.
[0054] FIG. 3 is a schematic diagram of a wristwatch fitted with an OLED display device 34 according to the invention. In the example shown, OLED display device 34 acts as the dial of watch 50 and a hole 48 , which passes through OLED display device 34 and substrate 1 , is advantageously used for the passage of two concentric arbours 52 and 54 respectively carrying an hour hand 56 and a minute hand 58 .
[0055] FIGS. 4A and 4B are top views of the first and second masks 60 and 62 used for the vapour deposition of spacer layer 18 and cathode layer 30 . According to the invention, spacer layer 18 and cathode layer 30 are deposited in two successive steps using first and second masks 60 and 62 . Therefore, first mask 60 comprises a first aperture 60 a corresponding to a first portion of the spacer layer 18 , respectively of the cathode layer 30 , to be deposited. First mask 60 also comprises a first cover portion 60 b for concealing all or part of the area of substrate 1 where it is desired to create exclusion areas 20 , 32 . Subsequently, the second mask 62 comprises a second aperture 62 a which is the complement of the first aperture 60 a arranged in the first mask 60 and which, if necessary, includes a second cover portion 62 b which is the complement of first cover portion 60 b and which conceals the rest of the area of substrate 1 where it is desired to create exclusion areas 20 and 32 . Finally, FIG. 4C shows that the joining of the first and second masks 60 and 62 enables the external contour of spacer layer 18 and of cathode layer 30 to be delimited with exclusion areas 20 and 32 at the centre of said two layers 18 and 30 . It will be clear that FIG. 4C is not an illustration of a step of the manufacturing method of the OLED display device of the invention, but it merely demonstrates that, placed end-to-end, the two masks 60 and 62 have perfectly complementary shapes which delimit the contour of spacer layer 18 and cathode layer 30 with the exclusion area at the centre.
[0056] It goes without saying that this invention is not limited to the embodiment that has just been described and that various simple modifications and variants can be envisaged by those skilled in the art without departing from the scope of the invention as defined by the annexed claims. It will be clear, in particular, that although it was mentioned above that the protuberance provided in the bottom face of the cover is located substantially at the centre of the OLED display device of the invention, it goes without saying that this protuberance may be located at any location on the bottom face of the cover. | Organic light emitting diode display device including a substrate covered by a cover which has a plane surface delimited along the external perimeter thereof. The plane surface of the cover is provided with a protuberance. The substrate is provided with a stack of layers, the stack of layers including at least the following layers in succession in the following order starting from the substrate: at least one anode; an insulating layer; a spacer layer which has a first exclusion area in a first area; an active hole injection layer, an active hole transport layer and an active electron transport layer; a cathode layer which has a second exclusion area. The protuberance of the cover is joined to the layer with which the protuberance is in contact, a hole, whose diameter is smaller than the geometrical dimensions of the protuberance, being made in the protuberance and through the substrate. | 7 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. application Ser. No. 12/036,910 filed Feb. 25, 2008, which is a continuation of U.S. application Ser. No. 11/707,946 filed on Feb. 20, 2007, now issued U.S. Pat. No. 7,354,208 which is a continuation of U.S. application Ser. No. 10/296,524 filed on Jul. 7, 2003, now issued U.S. Pat. No. 7,210,867, which is a 371 of PCT/AU00/00598 filed on May 24, 2000 all of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The following invention relates to a paper thickness sensor in a printer.
[0003] More particularly, though not exclusively, the invention relates to a paper thickness sensor used for adjusting the space between a printhead and a platen in an A4 pagewidth drop on demand printer capable of printing up to 1600 dpi photographic quality at up to 160 pages per minute.
[0004] The overall design of a printer in which the paper thickness sensor can be utilized revolves around the use of replaceable printhead modules in an array approximately 8 inches (20 cm) long. An advantage of such a system is the ability to easily remove and replace any defective modules in a printhead array. This would eliminate having to scrap an entire printhead if only one chip is defective.
[0005] A printhead module in such a printer can be comprised of a “Memjet” chip, being a chip having mounted thereon a vast number of thermo-actuators in micro-mechanics and micro-electromechanical systems (MEMS). Such actuators might be those as disclosed in U.S. Pat. No. 6,044,646 to the present applicant, however, there might be other MEMS print chips.
[0006] The printhead, being the environment within which the paper thickness sensor of the present invention is to be situated, might typically have six ink chambers and be capable of printing four color process (CMYK) as well as infra-red ink and fixative. An air pump would supply filtered air to the printhead, which could be used to keep foreign particles away from its ink nozzles. The printhead module is typically to be connected to a replaceable cassette which contains the ink supply and an air filter.
[0007] Each printhead module receives ink via a distribution molding that transfers the ink. Typically, ten modules butt together to form a complete eight inch printhead assembly suitable for printing A4 paper without the need for scanning movement of the printhead across the paper width.
[0008] The printheads themselves are modular, so complete eight inch printhead arrays can be configured to form printheads of arbitrary width.
[0009] Additionally, a second printhead assembly can be mounted on the opposite side of a paper feed path to enable double-sided high speed printing.
CO-PENDING APPLICATIONS
[0010] Various methods, systems and apparatus relating to the present invention are disclosed in the following co-pending applications filed by the applicant or assignee of the present invention simultaneously with the present application:
PCT/AU00/00518, PCT/AU00/00519, PCT/AU00/00520, PCT/AU00/00521, PCT/AU00/00522, PCT/AU00/00523, PCT/AU00/00524, PCT/AU00/00525, PCT/AU00/00526, PCT/AU00/00527, PCT/AU00/00528, PCT/AU00/00529, PCT/AU00/00530, PCT/AU00/00531, PCT/AU00/00532, PCT/AU00/00533, PCT/AU00/00534, PCT/AU00/00535, PCT/AU00/00536, PCT/AU00/00537, PCT/AU00/00538, PCT/AU00/00539, PCT/AU00/00540, PCT/AU00/00541, PCT/AU00/00542, PCT/AU00/00543, PCT/AU00/00544, PCT/AU00/00545, PCT/AU00/00547, PCT/AU00/00546, PCT/AU00/00554, PCT/AU00/00556, PCT/AU00/00557, PCT/AU00/00558, PCT/AU00/00559, PCT/AU00/00560, PCT/AU00/00561, PCT/AU00/00562, PCT/AU00/00563, PCT/AU00/00564, PCT/AU00/00565, PCT/AU00/00566, PCT/AU00/00567, PCT/AU00/00568, PCT/AU00/00569, PCT/AU00/00570, PCT/AU00/00571, PCT/AU00/00572, PCT/AU00/00573, PCT/AU00/00574, PCT/AU00/00575, PCT/AU00/00576, PCT/AU00/00577, PCT/AU00/00578, PCT/AU00/00579, PCT/AU00/00581, PCT/AU00/00580, PCT/AU00/00582, PCT/AU00/00587, PCT/AU00/00588, PCT/AU00/00589, PCT/AU00/00583, PCT/AU00/00593, PCT/AU00/00590, PCT/AU00/00591, PCT/AU00/00592, PCT/AU00/00584, PCT/AU00/00585, PCT/AU00/00586, PCT/AU00/00594, PCT/AU00/00595, PCT/AU00/00596, PCT/AU00/00597, PCT/AU00/00598, PCT/AU00/00516, PCT/AU00/00517, PCT/AU00/00511, PCT/AU00/00501, PCT/AU00/00502, PCT/AU00/00503, PCT/AU00/00504, PCT/AU00/00505, PCT/AU00/00506, PCT/AU00/00507, PCT/AU00/00508, PCT/AU00/00509, PCT/AU00/00510, PCT/AU00/00512, PCT/AU00/00513, PCT/AU00/00514, PCT/AU00/00515
[0012] The disclosures of these co-pending applications are incorporated herein by cross-reference.
OBJECTS OF THE INVENTION
[0013] It is an object of the present invention to provide a paper thickness sensor in a printer.
[0014] It is another object of the present invention to provide a paper thickness sensor used for adjusting a printhead-to-platen clearance for the pagewidth printhead assembly as broadly described herein.
[0015] It is another object of the present invention to provide a pagewidth printhead assembly having a paper thickness sensor therein to aid in adjusting a printhead-to-platen clearance.
[0016] It is yet another object of the present invention to provide a method of adjusting the clearance between a printhead and a platen in a pagewidth printhead assembly.
SUMMARY OF THE INVENTION
[0017] The present invention provides a pagewidth printer comprising:
[0018] a printhead having an array of fixed printing nozzles thereon,
[0019] a platen having a platen surface upon which a sheet rides to receive on a print surface thereof ink from said printing nozzles,
[0020] a sensor to measure an offset of said print surface with respect to said printing nozzles, and
[0021] means to effect movement of said platen to alter said offset.
[0022] Preferably the platen is mounted so as to rotate about a longitudinal axis thereof and said platen surface extends along the platen parallel with said axis at a non-constant distance from said axis such that compensatory rotation of the platen effects the offset of said print surface with respect to said printing nozzles.
[0023] Preferably the sensor is an optical sensor.
[0024] Preferably the optical sensor senses the position of a pivotal sensor flag that engages the print surface.
[0025] Preferably the sensor flag is mounted upon a spring-biased pivotal shaft mounted to the printhead.
[0026] The present invention also provides a method of adjusting an offset between an array of printing nozzles on a printhead and a print surface of a sheet riding upon a platen, the method comprising the steps of sensing the offset between the printhead and the print surface of the sheet and moving the platen so as to make any necessary compensation to said offset.
[0027] Preferably the platen includes a longitudinal axis and a platen surface parallel with said axis at a non-constant distance from said axis, the method including effecting compensatory rotation of the platen.
[0028] As used herein, the term “ink” is intended to mean any fluid which flows through the printhead to be delivered to a sheet. The fluid may be one of many different coloured inks, infra-red ink, a fixative or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings wherein:
[0030] FIG. 1 is a front perspective view of a print engine assembly
[0031] FIG. 2 is a rear perspective view of the print engine assembly of FIG. 1
[0032] FIG. 3 is an exploded perspective view of the print engine assembly of FIG. 1 .
[0033] FIG. 4 is a schematic front perspective view of a printhead assembly.
[0034] FIG. 5 is a rear schematic perspective view of the printhead assembly of FIG. 4 .
[0035] FIG. 6 is an exploded perspective illustration of the printhead assembly.
[0036] FIG. 7 is a cross-sectional end elevational view of the printhead assembly of FIGS. 4 to 6 with the section taken through the centre of the printhead.
[0037] FIG. 8 is a schematic cross-sectional end elevational view of the printhead assembly of FIGS. 4 to 6 taken near the left end of FIG. 4 .
[0038] FIG. 9A is a schematic end elevational view of mounting of the print chip and nozzle guard in the laminated stack structure of the printhead
[0039] FIG. 9B is an enlarged end elevational cross section of FIG. 9A FIG. 10 is an exploded perspective illustration of a printhead cover assembly.
[0040] FIG. 11 is a schematic perspective illustration of an ink distribution molding.
[0041] FIG. 12 is an exploded perspective illustration showing the layers forming part of a laminated ink distribution structure according to the present invention.
[0042] FIG. 13 is a stepped sectional view from above of the structure depicted in FIGS. 9A and 9B ,
[0043] FIG. 14 is a stepped sectional view from below of the structure depicted in FIG. 13 .
[0044] FIG. 15 is a schematic perspective illustration of a first laminate layer.
[0045] FIG. 16 is a schematic perspective illustration of a second laminate layer.
[0046] FIG. 17 is a schematic perspective illustration of a third laminate layer.
[0047] FIG. 18 is a schematic perspective illustration of a fourth laminate layer.
[0048] FIG. 19 is a schematic perspective illustration of a fifth laminate layer.
[0049] FIG. 20 is a perspective view of the air valve molding
[0050] FIG. 21 is a rear perspective view of the right hand end of the platen
[0051] FIG. 22 is a rear perspective view of the left hand end of the platen
[0052] FIG. 23 is an exploded view of the platen
[0053] FIG. 24 is a transverse cross-sectional view of the platen
[0054] FIG. 25 is a front perspective view of the optical paper sensor arrangement
[0055] FIG. 26 is a schematic perspective illustration of a printhead assembly and ink lines attached to an ink reservoir cassette.
[0056] FIG. 27 is a partly exploded view of FIG. 26 .
DETAILED DESCRIPTION OF THE INVENTION
[0057] In FIGS. 1 to 3 of the accompanying drawings there is schematically depicted the core components of a print engine assembly, showing the general environment in which the laminated ink distribution structure of the present invention can be located. The print engine assembly includes a chassis 10 fabricated from pressed steel, aluminium, plastics or other rigid material. Chassis 10 is intended to be mounted within the body of a printer and serves to mount a printhead assembly 11 , a paper feed mechanism and other related components within the external plastics casing of a printer.
[0058] In general terms, the chassis 10 supports the printhead assembly 11 such that ink is ejected therefrom and onto a sheet of paper or other print medium being transported below the printhead then through exit slot 19 by the feed mechanism. The paper feed mechanism includes a feed roller 12 , feed idler rollers 13 , a platen generally designated as 14 , exit rollers 15 and a pin wheel assembly 16 , all driven by a stepper motor 17 . These paper feed components are mounted between a pair of bearing moldings 18 , which are in turn mounted to the chassis 10 at each respective end thereof.
[0059] A printhead assembly 11 is mounted to the chassis 10 by means of respective printhead spacers 20 mounted to the chassis 10 . The spacer moldings 20 increase the printhead assembly length to 220 mm allowing clearance on either side of 210 mm wide paper.
[0060] The printhead construction is shown generally in FIGS. 4 to 8 .
[0061] The printhead assembly 11 includes a printed circuit board (PCB) 21 having mounted thereon various electronic components including a 64 MB DRAM 22 , a PEC chip 23 , a QA chip connector 24 , a microcontroller 25 , and a dual motor driver chip 26 . The printhead is typically 203 mm long and has ten print chips 27 ( FIG. 13 ), each typically 21 mm long. These print chips 27 are each disposed at a slight angle to the longitudinal axis of the printhead (see FIG. 12 ), with a slight overlap between each print chip which enables continuous transmission of ink over the entire length of the array. Each print chip 27 is electronically connected to an end of one of the tape automated bond (TAB) films 28 , the other end of which is maintained in electrical contact with the undersurface of the printed circuit board 21 by means of a TAB film backing pad 29 .
[0062] The preferred print chip construction is as described in U.S. Pat. No. 6,044,646 by the present applicant. Each such print chip 27 is approximately 21 mm long, less than 1 mm wide and about 0.3 mm high, and has on its lower surface thousands of MEMS inkjet nozzles 30 , shown schematically in FIGS. 9A and 9B , arranged generally in six lines—one for each ink type to be applied. Each line of nozzles may follow a staggered pattern to allow closer dot spacing. Six corresponding lines of ink passages 31 extend through from the rear of the print chip to transport ink to the rear of each nozzle. To protect the delicate nozzles on the surface of the print chip each print chip has a nozzle guard 43 , best seen in FIG. 9A , with microapertures 44 aligned with the nozzles 30 , so that the ink drops ejected at high speed from the nozzles pass through these microapertures to be deposited on the paper passing over the platen 14 .
[0063] Ink is delivered to the print chips via a distribution molding 35 and laminated stack 36 arrangement forming part of the printhead 11 . Ink from an ink cassette 37 ( FIGS. 26 and 27 ) is relayed via individual ink hoses 38 to individual ink inlet ports 34 integrally molded with a plastics duct cover 39 which forms a lid over the plastics distribution molding 35 . The distribution molding 35 includes six individual longitudinal ink ducts 40 and an air duct 41 which extend throughout the length of the array. Ink is transferred from the inlet ports 34 to respective ink ducts 40 via individual cross-flow ink channels 42 , as best seen with reference to FIG. 7 . It should be noted in this regard that although there are six ducts depicted, a different number of ducts might be provided. Six ducts are suitable for a printer capable of printing four color process (CMYK) as well as infra-red ink and fixative.
[0064] Air is delivered to the air duct 41 via an air inlet port 61 , to supply air to each print chip 27 , as described later with reference to FIGS. 6 to 8 , 20 and 21 .
[0065] Situated within a longitudinally extending stack recess 45 formed in the underside of distribution molding 35 are a number of laminated layers forming a laminated ink distribution stack 36 . The layers of the laminate are typically formed of micro-molded plastics material. The TAB film 28 extends from the undersurface of the printhead PCB 21 , around the rear of the distribution molding 35 to be received within a respective TAB film recess 46 ( FIG. 21 ), a number of which are situated along a chip housing layer 47 of the laminated stack 36 . The TAB film relays electrical signals from the printed circuit board 21 to individual print chips 27 supported by the laminated structure.
[0066] The distribution molding, laminated stack 36 and associated components are best described with reference to FIGS. 7 to 19 .
[0067] FIG. 10 depicts the distribution molding cover 39 formed as a plastics molding and including a number of positioning spigots 48 which serve to locate the upper printhead cover 49 thereon.
[0068] As shown in FIG. 7 , an ink transfer port 50 connects one of the ink ducts 39 (the fourth duct from the left) down to one of six lower ink ducts or transitional ducts 51 in the underside of the distribution molding. All of the ink ducts 40 have corresponding transfer ports 50 communicating with respective ones of the transitional ducts 51 . The transitional ducts 51 are parallel with each other but angled acutely with respect to the ink ducts 40 so as to line up with the rows of ink holes of the first layer 52 of the laminated stack 36 to be described below.
[0069] The first layer 52 incorporates twenty four individual ink holes 53 for each of ten print chips 27 . That is, where ten such print chips are provided, the first layer 52 includes two hundred and forty ink holes 53 . The first layer 52 also includes a row of air holes 54 alongside one longitudinal edge thereof.
[0070] The individual groups of twenty four ink holes 53 are formed generally in a rectangular array with aligned rows of ink holes. Each row of four ink holes is aligned with a transitional duct 51 and is parallel to a respective print chip.
[0071] The undersurface of the first layer 52 includes underside recesses 55 . Each recess 55 communicates with one of the ink holes of the two centre-most rows of four holes 53 (considered in the direction transversely across the layer 52 ). That is, holes 53 a ( FIG. 13 ) deliver ink to the right hand recess 55 a shown in FIG. 14 , whereas the holes 53 b deliver ink to the left most underside recesses 55 b shown in FIG. 14 .
[0072] The second layer 56 includes a pair of slots 57 , each receiving ink from one of the underside recesses 55 of the first layer.
[0073] The second layer 56 also includes ink holes 53 which are aligned with the outer two sets of ink holes 53 of the first layer 52 . That is, ink passing through the outer sixteen ink holes 53 of the first layer 52 for each print chip pass directly through corresponding holes 53 passing through the second layer 56 .
[0074] The underside of the second layer 56 has formed therein a number of transversely extending channels 58 to relay ink passing through ink holes 53 c and 53 d toward the centre. These channels extend to align with a pair of slots 59 formed through a third layer 60 of the laminate. It should be noted in this regard that the third layer 60 of the laminate includes four slots 59 corresponding with each print chip, with two inner slots being aligned with the pair of slots formed in the second layer 56 and outer slots between which the inner slots reside.
[0075] The third layer 60 also includes an array of air holes 54 aligned with the corresponding air hole arrays 54 provided in the first and second layers 52 and 56 .
[0076] The third layer 60 has only eight remaining ink holes 53 corresponding with each print chip. These outermost holes 53 are aligned with the outermost holes 53 provided in the first and second laminate layers. As shown in FIGS. 9A and 9B , the third layer 60 includes in its underside surface a transversely extending channel 61 corresponding to each hole 53 . These channels 61 deliver ink from the corresponding hole 53 to a position just outside the alignment of slots 59 therethrough.
[0077] As best seen in FIGS. 9A and 9B , the top three layers of the laminated stack 36 thus serve to direct the ink (shown by broken hatched lines in FIG. 9B ) from the more widely spaced ink ducts 40 of the distribution molding to slots aligned with the ink passages 31 through the upper surface of each print chip 27 .
[0078] As shown in FIG. 13 , which is a view from above the laminated stack, the slots 57 and 59 can in fact be comprised of discrete co-linear spaced slot segments.
[0079] The fourth layer 62 of the laminated stack 36 includes an array of ten chip-slots 65 each receiving the upper portion of a respective print chip 27 .
[0080] The fifth and final layer 64 also includes an array of chip-slots 65 which receive the chip and nozzle guard assembly 43 .
[0081] The TAB film 28 is sandwiched between the fourth and fifth layers 62 and 64 , one or both of which can be provided with recesses to accommodate the thickness of the TAB film.
[0082] The laminated stack is formed as a precision micro-molding, injection molded in an Acetal type material. It accommodates the array of print chips 27 with the TAB film already attached and mates with the cover molding 39 described earlier.
[0083] Rib details in the underside of the micro-molding provides support for the TAB film when they are bonded together. The TAB film forms the underside wall of the printhead module, as there is sufficient structural integrity between the pitch of the ribs to support a flexible film. The edges of the TAB film seal on the underside wall of the cover molding 39 . The chip is bonded onto one hundred micron wide ribs that run the length of the micro-molding, providing a final ink feed to the print nozzles.
[0084] The design of the micro-molding allow for a physical overlap of the print chips when they are butted in a line. Because the printhead chips now form a continuous strip with a generous tolerance, they can be adjusted digitally to produce a near perfect print pattern rather than relying on very close toleranced moldings and exotic materials to perform the same function. The pitch of the modules is typically 20.33 mm.
[0085] The individual layers of the laminated stack as well as the cover molding 39 and distribution molding can be glued or otherwise bonded together to provide a sealed unit. The ink paths can be sealed by a bonded transparent plastic film serving to indicate when inks are in the ink paths, so they can be fully capped off when the upper part of the adhesive film is folded over. Ink charging is then complete.
[0086] The four upper layers 52 , 56 , 60 , 62 of the laminated stack 36 have aligned air holes 54 which communicate with air passages 63 formed as channels formed in the bottom surface of the fourth layer 62 , as shown in FIGS. 9 b and 13 . These passages provide pressurised air to the space between the print chip surface and the nozzle guard 43 whilst the printer is in operation. Air from this pressurised zone passes through the micro-apertures 44 in the nozzle guard, thus preventing the build-up of any dust or unwanted contaminants at those apertures. This supply of pressurised air can be turned off to prevent ink drying on the nozzle surfaces during periods of non-use of the printer, control of this air supply being by means of the air valve assembly shown in FIGS. 6 to 8 , 20 and 21 .
[0087] With reference to FIGS. 6 to 8 , within the air duct 41 of the printhead there is located an air valve molding 66 formed as a channel with a series of apertures 67 in its base. The spacing of these apertures corresponds to air passages 68 formed in the base of the air duct 41 (see FIG. 6 ), the air valve molding being movable longitudinally within the air duct so that the apertures 67 can be brought into alignment with passages 68 to allow supply the pressurized air through the laminated stack to the cavity between the print chip and the nozzle guard, or moved out of alignment to close off the air supply. Compression springs 69 maintain a sealing inter-engagement of the bottom of the air valve molding 66 with the base of the air duct 41 to prevent leakage when the valve is closed.
[0088] The air valve molding 66 has a cam follower 70 extending from one end thereof, which engages an air valve cam surface 71 on an end cap 74 of the platen 14 so as to selectively move the air valve molding longitudinally within the air duct 41 according to the rotational positional of the multi-function platen 14 , which may be rotated between printing, capping and blotting positions depending on the operational status of the printer, as will be described below in more detail with reference to FIGS. 21 to 24 . When the platen 14 is in its rotational position for printing, the cam holds the air valve in its open position to supply air to the print chip surface, whereas when the platen is rotated to the non-printing position in which it caps off the micro-apertures of the nozzle guard, the cam moves the air valve molding to the valve closed position.
[0089] With reference to FIGS. 21 to 24 , the platen member 14 extends parallel to the printhead, supported by a rotary shaft 73 mounted in bearing molding 18 and rotatable by means of gear 79 (see FIG. 3 ). The shaft is provided with a right hand end cap 74 and left hand end cap 75 at respective ends, having cams 76 , 77 .
[0090] The platen member 14 has a platen surface 78 , a capping portion 80 and an exposed blotting portion 81 extending along its length, each separated by 120°. During printing, the platen member is rotated so that the platen surface 78 is positioned opposite the printhead so that the platen surface acts as a support for that portion of the paper being printed at the time. When the printer is not in use, the platen member is rotated so that the capping portion 80 contacts the bottom of the printhead, sealing in a locus surrounding the microapertures 44 . This, in combination with the closure of the air valve by means of the air valve arrangement when the platen 14 is in its capping position, maintains a closed atmosphere at the print nozzle surface. This serves to reduce evaporation of the ink solvent (usually water) and thus reduce drying of ink on the print nozzles while the printer is not in use.
[0091] The third function of the rotary platen member is as an ink blotter to receive ink from priming of the print nozzles at printer start up or maintenance operations of the printer. During this printer mode, the platen member 14 is rotated so that the exposed blotting portion 81 is located in the ink ejection path opposite the nozzle guard 43 . The exposed blotting portion 81 is an exposed part of a body of blotting material 82 inside the platen member 14 , so that the ink received on the exposed portion 81 is drawn into the body of the platen member.
[0092] Further details of the platen member construction may be seen from FIGS. 23 and 24 . The platen member consists generally of an extruded or molded hollow platen body 83 which forms the platen surface 78 and receives the shaped body of blotting material 82 of which a part projects through a longitudinal slot in the platen body to form the exposed blotting surface 81 . A flat portion 84 of the platen body 83 serves as a base for attachment of the capping member 80 , which consists of a capper housing 85 , a capper seal member 86 and a foam member 87 for contacting the nozzle guard 43 .
[0093] With reference again to FIG. 1 , each bearing molding 18 rides on a pair of vertical rails 101 . That is, the capping assembly is mounted to four vertical rails 101 enabling the assembly to move vertically. A spring 102 under either end of the capping assembly biases the assembly into a raised position, maintaining cams 76 , 77 in contact with the spacer projections 100 .
[0094] The printhead 11 is capped when not is use by the full-width capping member 80 using the elastomeric (or similar) seal 86 . In order to rotate the platen assembly 14 , the main roller drive motor is reversed. This brings a reversing gear into contact with the gear 79 on the end of the platen assembly and rotates it into one of its three functional positions, each separated by 120°.
[0095] The cams 76 , 77 on the platen end caps 74 , 75 co-operate with projections 100 on the respective printhead spacers 20 to control the spacing between the platen member and the printhead depending on the rotary position of the platen member. In this manner, the platen is moved away from the printhead during the transition between platen positions to provide sufficient clearance from the printhead and moved back to the appropriate distances for its respective paper support, capping and blotting functions.
[0096] In addition, the cam arrangement for the rotary platen provides a mechanism for fine adjustment of the distance between the platen surface and the printer nozzles by slight rotation of the platen 14 . This allows compensation of the nozzle-platen distance in response to the thickness of the paper or other material being printed, as detected by the optical paper thickness sensor arrangement illustrated in FIG. 25 .
[0097] The optical paper sensor includes an optical sensor 88 mounted on the lower surface of the PCB 21 and a sensor flag arrangement mounted on the arms 89 protruding from the distribution molding. The flag arrangement comprises a sensor flag member 90 mounted on a shaft 91 which is biased by torsion spring 92 . As paper enters the feed rollers, the lowermost portion of the flag member contacts the paper and rotates against the bias of the spring 92 by an amount dependent on the paper thickness. The optical sensor detects this movement of the flag member and the PCB responds to the detected paper thickness by causing compensatory rotation of the platen 14 to optimize the distance between the paper surface and the nozzles.
[0098] FIGS. 26 and 27 show attachment of the illustrated printhead assembly to a replaceable ink cassette 93 . Six different inks are supplied to the printhead through hoses 94 leading from an array of female ink valves 95 located inside the printer body. The replaceable cassette 93 containing a six compartment ink bladder and corresponding male valve array is inserted into the printer and mated to the valves 95 . The cassette also contains an air inlet 96 and air filter (not shown), and mates to the air intake connector 97 situated beside the ink valves, leading to the air pump 98 supplying filtered air to the printhead. A QA chip is included in the cassette. The QA chip meets with a contact 99 located between the ink valves 95 and air intake connector 96 in the printer as the cassette is inserted to provide communication to the QA chip connector 24 on the PCB. | A printhead assembly includes an elongate ink distribution assembly defining elongate ink ducts from which ink transfer ports extend. The ink distribution assembly further defines a recess in which a laminated stack structure is received in fluid communication with the ink transfer ports. The laminated stack structure has layers between which ink channels in fluid communication with the ports are interleaved. The laminated stack defines at least one cavity in which respective ink ejection print head integrated circuits (ICs) can be received in fluid communication with the ink channels. The cavity is formed in the laminated stack structure so that the ICs can be disposed at a slight angle to the longitudinal axis of the ink distribution assembly. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a print head of a printer.
PRIOR ART
A conventional print head is disclosed in Japanese Utility Model Laid Open No. 62-94843, filed by different inventors for the present assignee.
That print head consists of an armature unit having an armature base, a solenoid unit having a solenoid base and a wire unit having a nose portion.
Plural armatures and armature springs are circularly arranged with respect to the armature base and also magnetic drive units having a core and a solenoid corresponding to each armature are installed on the armature base.
Plural wires are connected to each armature at one end and project through a nose portion at the other end. The wires project from a front face via operation of the armature by driving of the magnetic drive unit and thus print dots in a matrix that form a printed character on a piece of paper or other substrate.
DEFECTS OF SUCH CONVENTIONAL PRINT HEAD
The described conventional print head uses polyphenylene sulfide (hereinafter referred to as PPS) as a material of the armature base.
It has a defect in that the armature base produces a high level of noise.
The armature base of such a print head is required to have excellent resistance to thermal deformation properties and resistance to wear.
Resistance to thermal deformation is required for preventing irregular printing caused by deformation of the armature base by the heat from plural magnetic drive units which cause high temperatures.
Resistance to wear is required for preventing a reduction in the life of the print head due to wear of the armature base caused by numerous sliding or bumping actions thereon.
PPS is excellent in resistance to thermal deformation and wear but it is poor in preventing vibration and is very noisy upon printing.
As a means for preventing this noise, the addition of metal to the rear face of the armature base is disclosed in Japanese Utility Model Publication 62-32857. However, the resultant print head is heavy due to the presence of the metal. Thus, it is necessary to increase the power of the motor, enlarge the timing belt, and thicken the related shafts for moving the carriage body with the heavier print head thereon.
The inertia of such a print head has a substantial effect on the quality of the printing, and it is also uneconomical in that it requires many parts. The printing is affected in that the increased inertia slows the rate of change of the direction of printing, and the speed of moving the carriage can not match the speed of the print head as closely. Accordingly, in such printers where the print head is reciprocated to begin each line, the beginning of each successive line of print is affected, characters are misaligned, and the quality of printing deteriorates.
An object of the present invention is to eliminate the above-discussed defects of the conventional print head by means of forming the armature base from materials having good resistance to thermal deformation, wear, and vibration.
BRIEF SUMMARY OF THE INVENTION
The foregoing defects are eliminated by the use of an armature base formed from a liquid crystal polymer of an aromatic series polyester resin which has damping properties in addition to resistance to thermal deformation and wear.
Therefore, vibration attenuation of various noises which are caused during operating of the print head occurs quickly and noises radiated from the print head are reduced.
The force of impact from bumping of the armature may be absorbed by the armature base because it is formed from the liquid crystal polymer of aromatic series polyester resin.
Therefore, noise which occurs upon the striking or bumping of the armature may be kept very low, and a low noise printer is thus provided.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described more fully with reference to the accompanying drawings, in which:
FIG. 1 is a longitudinal sectional view of an embodiment of the present invention;
FIG. 2 is a sectional view showing the guiding of the armature;
FIG. 3 is a graph showing characteristics of a liquid crystal polymer of an aromatic series polyester resin; and
FIG. 4 is a perspective view showing an embodiment in which the print head of the present invention is incorporated.
DETAILED DESCRIPTION OF THE INVENTION
First, the construction of an embodiment of the present invention is as depicted by FIGS. 1 and 2.
In FIG. 1, 1 is an armature unit, 2 is solenoid unit, and 3 is a wire unit.
The solenoid unit 2 is arranged between the armature unit 1 and the wire unit 3. These three units 1-3 are connected by fastener 4 and the print head A is thus constructed.
The armature unit 1 has an armature base 6 the rear face of which is strengthened by rib 5. Plural armatures 7 are arranged circularly on the front of the armature base 6 and armature springs 8, having as many spring portions as the armatures 7, are arranged between each armature 7 and armature base 6.
On the center of the armature base 6, an armature stopper 13 is fixed in order to determine the waiting position of the armature 7.
On the front the armature base 6, a projection 9 for guiding the top of armature 7 corresponding to each armature 7, a base side projection 10 for guiding the armature 7 to the armature base 6 upon construction, and a positioning projection 12 for positioning and holding the armature 7 by being inserted in the positioning hole 11 of the armature 7 are provided.
The armature base 6 is formed of liquid crystal polyester of aromatic series polyester resin.
This liquid crystal polymer of aromatic series polymer resin is a kind of a liquid crystal polymer and an aromatic series polyester resin such as "VECTRA" (a trademark of the HOECHST CELANESE CORP.).
"VECTRA" is a firm, high molecular weight polymer and there are very few molecular entanglements because the molecular chain continues to stick together due to being hard to bend even if it is in a molten state.
Therefore, "VECTRA" is characterized by the fact that it may be oriented in one direction by receiving slight shear stress.
"VECTRA" is referred to as a liquid crystal polymer given that it has the characteristics of a crystal in spite of its liquid state.
"VECTRA" has many excellent characteristics produced by such distinctive fine structure.
Particularly the vibration absorption characteristics of "VECTRA" are very excellent despite its high elasticity modulus. This is a unique characteristic which other resins do not have.
One example of such characteristic is shown in a graph of FIG. 3.
This graph shows the relation between attenuation characteristics and elasticity modulus in various materials.
The ordinate represents the elastic modulus in tension (kfg/cm 2 ) and the abscissa represents internal loss (η).
Generally, the attenuation (internal loss) of metal materials such as aluminum having a high elasticity modulus is small, and the attenuation of materials such as rubber having low elasticity modulus is large.
Namely, high rigidity is generally contrary to good attenuation properties.
As shown in FIG. 3, "VECTRA" has high attenuation properties despite having a high elasticity modulus.
An object of the present invention is to apply this characteristic of "VECTRA," and like compounds to the armature base of a print head and the like.
The ratio of the internal loss between "VECTRA" and PPS is in the range of 6-10. Namely, the internal loss of VECTRA is 6 to 10 times as much as the internal loss of PPS under similar conditions.
VECTRA is available in various grades, and it has been found by the inventors that VECTRA A950 and VECTRA A230 are both especially suited for use in the present invention. (HOECHST CELANESE has characterized VECTRA A950 as follows:
"Not recommended for injection molding; surface fibrillation too difficult to control. General purpose base resin used for extrusion and compounding."
and VECTRA A230 as follows:
"General purpose carbon fiber reinforced grade; very high strength and stiffness; easy flow; electrically conductive; excellent wear/bearing material; exceptionally good chemical resistance and hydrolytic stability."
A typical VECTRA molecule: ##STR1##
The solenoid unit 2 has a solenoid base 14 which has a cup shape and as many magnetic drive units 15 as armatures 7 which are arranged circularly on bottom surface of the solenoid base 14.
An annular magnetism preventing plate 16 is installed between armature unit 1 and the solenoid unit 2.
Each magnetic drive unit 15 has a core 17 fixed on the solenoid base 14, a bobbin 18 fitted into the core 17 and a solenoid 19 wrapped to the bobbin 18.
On the opposite side of core 17 of the solenoid base 14, a flexible print plate 21 is arranged via an insulator 20. The both ends of the solenoid 19 are soldered to the flexible print plate 21.
The wire unit 3 has a nose 23 fitted onto a cylindrical portion 22 thereof to a center opening of the solenoid base 14 and plural wires 24 slidably guided by the nose 23.
These are as many wires 24 as there are armatures 7. The points are arranged linearly and the rear ends are arranged circularly.
Wire pin 25 is fixed to the rear end of each wire 24. Each wire 24 touches the corresponding armature 7 through the wire pin 25.
26 is a return spring for backing the points of the wires 24 up to the front face of the nose 23 by means of pressing wires 24 toward armature 7.
The print head as described above is incorporated in a printer as shown in FIG. 4.
In FIG. 4, 30 is a carriage body having the print head A installed therein.
The carriage body 30 is slidably held by two guide shafts 31, 32 which are arranged in parallel. 33 is an endless timing belt which is drivable with the carriage body 30. 34 is a motor for driving the timing belt 33.
The carriage 30 is moved reciprocally in the right and left directions on the front face of the platen 35 with the timing belt 33 by means of a driving motor 34.
The action of the present invention will now be described.
If the solenoid 19 of the magnetic drive unit 15 is not energized, the wires 24 are at the back by pressing of the return spring 26 and armature spring 8.
Therefore, the armature 7 touches the armature base 6 through the armature stopper 13.
When the solenoid 19 is energized, the armature 7 is attracted by the core 17 and the armature 7 swings or rotates positioning projection 12 of the armature base 6 as a center.
The armature 7 is thus separated from the armature base 6 by this swinging motion and touches core 17 through the residual 16.
As the rear ends of the wire pins 25 which are fixed on the point of the armature 7 are pressed, the wires 24 are projected from the front surface of the nose 23 and the wires 24 press the paper 36 to the platen 35 through an ink ribbon (not shown).
Thus, the desired print character is dot-printed on a paper 36 which is wrapped around and abutting against platen 35, as seen in FIG. 4.
If the excitation of the solenoid 19 is discontinued, the armature 7 swings back in the opposite direction under the biasing force of the armature spring 8, thereby returning to a starting position in contact with the armature stopper 13.
The wires 24 are backed by pressure of the return spring 26, while following motion of the armature 7. In this case, for every reciprocating movement of the armature 7, this armature 7 bumps one time against the armature base 6 through the armature stopper 13.
Given that the armature base 6 is formed from a liquid crystal polymer of aromatic series polyester resin having excellent vibration attenuation characteristics vibration caused by the colliding with or bumping of armature 7 is absorbed by armature base 6.
Therefore, loud noise is not generated even though the armatures 7 bump the armature base 6 continuously.
Armature base 6, formed from a liquid crystal polymer of aromatic series polyester resin, has both resistance to thermal deformation properties and resistance to wear, which properties are required for armature base 6. In addition to excellent vibration attenuation characteristics as described above, this armature base 6 does not deform under the influence of heat or wear even if printing by continuous driving of the magnetic drive unit 5 occurs for a long time. In other words, both noise is reduced and thermal and abrasion resistance are achieved even under prolonged use conditions.
If the liquid crystal polymer of the aromatic series polyester resin is used as the material of nose 23 or carriage body 30, it may efficiently prevent transmission of vibrations occurring at the print head to the frame from the nose 23 or the carriage body 30 through the guide shafts 31, 32.
Therefore, if the nose 23 and carriage body 30 are formed from a liquid crystal polymer of the aromatic series polyester resin, it will be able to efficiently prevent the generation of noise from the frame and other parts.
The foregoing is simply a description of preferred embodiments of Applicants' invention, and should not be construed as limiting the scope of the invention in any manner. All variations possible within the scope of the appended claims are to be considered as coming with the bounds of the invention. | An improved print head for a dot matrix printer is provided. The printing is performed by wires projecting from said print head. The movement of the wires is controlled by the movement of armatures which contact an armature base. The construction of the base from a liquid crystal polymer or an aromatic series polyester resin results in improved vibration damping which in turn results in quieter printer operation. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of co-pending U.S. application Ser. No. 10/670, 973 filed Sep. 25, 2003, which is incorporated by reference. Further, pursuant to 35 U.S.C. §119(a), this application claims the benefit of earlier filing date and right of Korean Patent Application No. 10-2003-14164, filed on Mar. 6, 2003, the content of which is hereby incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention relates to a method for setting a playback environment for reproducing audio/video (A/V) data in an interactive or enhanced recording medium, such as an interactive digital versatile disk (also known as I-DVD or Enhanced Digital Versatile Disk (ENAV)), along with additional contents associated with the A/V data. of permanently recording and storing not only high-quality digital audio data, but also high-quality moving picture data.
[0003] A DVD includes a data stream recording area for recording a digital data stream, such as moving picture data and a navigation data recording area for recording navigation data needed for controlling playback of the moving picture data. A typical DVD player first reads the navigation-data recorded on the navigation data recording area, if the DVD is seated in the player, stores the read navigation data in a memory provided in the player, and reproduces the moving picture data recorded on the data stream recording area using the navigation data.
[0004] The DVD player reproduces the moving picture data recorded on the DVD, such that a user can view and hear a movie recorded on the DVD. Information (control or additional information) associated with the playback of audio/video (A/V) data recorded on the DVD can be recorded as a file written in a hypertext markup language (HTML) on the DVD. Standardization work of an interactive digital versatile disk (I-DVD) is ongoing. The A/V data recorded on the I-DVD is reproduced according to the user's interactive request. Where I-DVDs are commercialized, the supply of contents through digital recording mediums will be more prevalent.
[0005] A method is being developed for seamlessly and continuously reproducing A/V data in an I-DVD, at the time of a synchronous playback operation for the A/V data and additional contents, i.e., ENAV data, associated with the A/V data recorded on the DVD. Various playback environments must be set before the data of the disk is reproduced so that the A/V data and the ENAV data on the disk can be seamlessly reproduced and outputted under limited resources of the player.
SUMMARY OF THE INVENTION
[0006] In accordance with one or more embodiments, a method for connecting a media player to a remote server comprises processing a request for connecting to an remote server while reproducing data recorded on an enhanced navigation medium; processing connection information recorded on the enhanced navigation medium to determine whether connection to the remote server is permitted; and requesting connection to the remote server, if connection to the remote server is permitted in accordance with the connection information.
[0007] The connection information is recorded in a start-up file that is read prior to reproduction of the data recorded on the enhanced navigation medium. The start-up file comprises information associated with a list of additional contents to be loaded before the data on the enhanced navigation medium is reproduced. The start-up file comprises information associated with a right to reproduce the data recorded on the enhanced navigation medium.
[0008] In some embodiments, the start-up file comprises information associated with a region code, a language of the additional contents, memory management, and a file to be processed after the start-up file is processed. The connection information comprises a list of servers to which the media player may connect or alternatively a list of servers to which the media player may not connect.
[0009] The data recorded on the enhanced navigation medium comprises audio/video (A/V) data. The data recorded on the enhanced navigation medium comprises additional contents associated with the A/V data, in some embodiments, for example. The A/V data and the additional contents are reproduced in synchronization.
[0010] The connection information comprises at least one connection address for connecting to the remote server. The start-up file comprises the connection information, wherein the start-up file comprises information associated with a walled-garden file comprising location information about at least one server.
[0011] The walled-garden file comprises information about at least one server to which the media player may connect to retrieve additional contents associated with the data recorded on the enhanced navigation medium. In one embodiment, the walled-garden file comprises information about at least one server to which the media player may not connect to retrieve additional contents associated with the data recorded on the enhanced navigation medium.
[0012] The walled-garden file comprises at least one entry associated with loading information that controls access to information available on the at least one server. The loading information comprises at least a condition for loading information available on the at least one server, and at least one of a language or a profile supported by the media player.
[0013] In one or more embodiments, a method for processing a connection request of an enhanced navigation media player comprises determining a current operating mode and connection limitation information, in response to a connection request for connecting the player to a remote server; and submitting the request to the remote server to establish a connection, based on the current operating mode and the connection limitation information.
[0014] The connection request is submitted, if the current operating mode is an enhanced navigation playback mode. Also, the connection request is submitted, if the connection limitation information provides permission for the remote server to be contacted. That is, the connection request is submitted, if the current operating mode is an interactive disk playback mode and if the connection limitation information indicates that the remote server may be contacted.
[0015] In certain embodiments, the connection limitation information is included in a start-up file residing on an enhanced navigation medium. The start-up file is read prior to the player reproducing data recorded on the enhanced navigation medium. The start-up file comprises information associated with a list of additional contents to be loaded before data recorded on the enhanced navigation medium is reproduced.
[0016] In accordance with another embodiment, an enhanced navigation media player for processing data recorded on a recording medium is provided. The player comprises an audio/video (A/V) player engine; and an enhance navigation (ENAV) engine, wherein if the recording medium is not an enhance navigation medium then A/V data recorded on the recording medium is reproduced by the A/V player engine, and wherein if the recording medium is an enhanced navigation medium, then a start-up file is loaded into a first memory so that the ENAV engine can extract connection information about at least one server with additional contents.
[0017] In one or more embodiments, the start-up file comprises information associated with a walled-garden list that provides the connection information about the at least one server. The start-up file may also comprise loading information that controls access to the additional contents available on the at least one server. The loading information comprises at least a condition for loading the additional contents available on the at least one server, a language condition to limit access to the additional contents available on the at least one server based on the language condition, a profile condition to limit access to the additional contents available on the at least one server based on the profile condition, and parental condition to limit access to the additional contents available on the at least one server based on the parental condition.
[0018] In some embodiments, an enhanced navigation recording medium comprises audio/video (A/V) data; and connection information for controlling access to additional contents available through at least one remote server, wherein the additional contents is reproduced in synchronization with the A/V data. The connection information comprises at least a condition for loading the additional contents available on the at least one server and a language condition to limit access to the additional contents available on the at least one server based on the language condition.
[0019] A profile condition to limit access to the additional contents available on the at least one server based on the profile condition, and parental condition to limit access to the additional contents available on the at least one server based on the parental condition, may be also included. In one embodiment, the connection information limits access to the at least one remote server or permits access to the at least one remote server.
[0020] In accordance with yet another embodiment, a method of playing back audio/video (A/V) data recorded on an enhanced navigation medium comprises identifying a playback mode; decoding a start-up file recorded on the enhanced navigation medium, if the playback mode identifies an enhanced navigation mode, wherein the start-up file comprises first an second information; decoding the first information to determine location of at least one remote server that provides access to additional contents to be played back in synchronization with the A/V data; and decoding the second information to determine at least one condition associated with the additional contents.
[0021] In one embodiment, a first enhanced navigation application is launched based on the decoded first and second information. The second information comprises at least one of a profile, language, and parental condition for loading the additional contents, for example.
[0022] These and other embodiments of the present invention will also become readily apparent to those skilled in the art from the following detailed description of the embodiments having reference to the attached figures, the invention not being limited to any particular embodiments disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
[0024] FIG. 1 is a block diagram of an optical disk device to which a method for setting a playback environment of an interactive disk, in accordance with one embodiment of the invention, is applied;
[0025] FIG. 2 is a schematic diagram illustrating a directory structure of an interactive digital versatile disk (I-DVD) in accordance with one embodiment of the invention; and
[0026] FIG. 3 is a flowchart illustrating a method for setting the playback environment of the interactive disk, in accordance with an embodiment of the invention.
[0027] Features, elements, and aspects of the invention that are referenced by the same numerals in different figures represent the same, equivalent, or similar features, elements, or aspects in accordance with one or more embodiments of the system.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] Referring to FIG. 1 , in accordance with one embodiment of the present invention, an optical disk device comprises an optical pickup 11 that reads a signal recorded on an enhanced navigation recording medium such as an interactive digital versatile disk (I-DVD) 10 . A signal processor 12 processes a read radio frequency (RF) signal and recovers digital data. A memory unit 13 stores the recovered data and externally received data. A DVD engine 14 decodes the data stored in the memory unit 13 . An iDVD engine 15 interprets an information file stored in the memory unit 13 , and processes certain additional contents (i.e., ENAV data).
[0029] A synthesizer 18 synthesizes and outputs an A/V signal from the DVD engine 14 and another A/V signal from the iDVD engine 15 . A network interface 17 performs a network connection function and a web browser function. A control unit 16 sets a playback environment of the I-DVD 10 and controls the above-described components so that data of the I-DVD 10 can be reproduced along with the additional contents, under the set playback environment.
[0030] An exemplary directory structure of the I-DVD 10 is shown in FIG. 2 . An additional contents directory “DVD_ENAV” 203 is arranged under a root directory and comprises a start-up file “StartUp.mls” 204 , for example. The start-up files comprises information about the system environment settings. In some embodiments, the environment is set before data of the I-DVD is reproduced.
[0031] An information file “EnDVD.Inf”, for example, for reproducing A/V data recorded on the I-DVD, an initial screen setup file “index.html”, for example, for playback, and synchronization file “index.syn”, for example, for the synchronization between data items of different attributes may be part of the start-up file or settings. The directory “DVD_ENAV” 203 may further comprise a fonts directory 206 storing font files for outputting a text of the additional contents.
[0032] In some embodiments, an additional contents directory 207 comprising the additional contents for providing additional A/V contents (i.e., ENAV data files 208 , html files, image files, sound files, etc.) may be present. The additional contents directory 207 can comprise additional contents (for example, e.g., subdirectories 209 ), on the basis of a hierarchical structure, for example.
[0033] A video title set directory “Video TS” 201 , for example, comprising video data and an audio title set directory “Audio_TS” 202 , for example, comprising audio data is arranged under the root directory, in some embodiments. An item of disk version information associated with the I-DVD and an item of contents manufacturer information are recorded in, for example, the “EnDvd.inf” file of the directory 203 . Further, uniformed resource identifier (URI) information associated with a contents provider's server for providing, through a communication network, the additional contents information relating to A/V data to be read and reproduced from the I-DVD can be recorded in the directory 203 .
[0034] Items of setup information for the initial screen setting at the time of reproducing the data of the interactive DVD can be recorded in the setup file “index.html” of the directory 203 . Items of time stamp information for performing the synchronization between the A/V data and ENAV data to be read and reproduced from the I-DVD are recorded in the synchronization file “index.syn”.
[0035] Before the A/V data of the I-DVD is reproduced, various information items for system environment setting are recorded in the start-up file “StartUp.mls”, for example. The various information items may comprise information about contents to be loaded in a memory before the playback, location information of a source for providing the contents information, a parental ID indicating a right to access the recorded A/V data, the language of the additional contents, a website connection during the playback, memory management information, a file to be processed after the start-up file is processed, and a version of the start-up file.
[0036] Referring to FIG. 3 , a method for reproducing the data of the I-DVD 10 is provided. If a disk is inserted and seated within the player shown in FIG. 1 , at step S 1 , then the control unit 16 searches for a “StartUp.mls” or “EnDVD.Inf” file from a “DVD_ENAV” directory, for example. If a corresponding file is found, the seated disk is detected as an I-DVD, at step S 10 . Otherwise, the seated disk is detected as a general DVD.
[0037] If the seated disk is a general DVD, the control unit 16 performs a playback operation in a general DVD mode in response to a user request, at step S 30 . If the playback operation is completed, procedure ends. In the playback operation of the DVD mode, data reproduced from the disk is processed through the DVD engine 14 and the processed data is outputted as a video and audio signal.
[0038] On the other hand, if the seated disk is an I-DVD 10 , it is determined whether data of the I-DVD is to be reproduced in an enhanced mode, at step S 11 . The enhanced mode is a synchronous playback mode for the additional data (i.e., ENAV data). The enhanced mode can be turned ON/OFF by the user. The initial setting corresponds to an ON state, in one embodiment. If the enhanced mode is in an OFF state, the above-described general DVD playback operation is performed at the above step S 30 , even if the seated disk is an I-DVD.
[0039] In certain embodiments, if the enhanced mode is in an ON state, the start-up file “StartUp.mls”, for example, arranged under the “DVD_ENAV” directory is read, at step S 12 . The start-up file is stored in the memory unit 13 , and the iDVD engine 15 is requested to interpret the start-up file. In one embodiment, the iDVD engine 15 interprets the start-up file “StartUp.mls” stored in the memory unit 13 , and confirms a parental ID for authorization to reproduce data of the I-DVD at step S 13 . The iDVD engine then sets a system state, at step S 14 .
[0040] Information of the system state comprises information associated with a language to be used at a time of processing the ENAV data, website connection limitation (i.e., walled garden list), memory management, loading information, etc. For example, the system state can be defined as:
<conf type=language con=euc-kr> <wgarden>http://www.warner.com</wgarden> <memset> <pload>36</pload> </memset>
[0041] In this exemplary embodiment, The tag “<conf type>”, for example, designates the Korean language as the used language. A tag “<wgarden>”, for example, designates the website connection limitation or the walled garden list. The tag “<wgarden>”, for example, indicates that connections to web sites other than “http://www.warner.com”, for example, are not allowed. In conjunction with the memory setting, a tag “<pload>”, for example, designates a memory space to be occupied. The tag “<pload>” indicates that a memory space of 36 Mbytes in the memory is occupied, in one or more embodiments. The loading information, for example defines a list of URIs to be preloaded into a memory space and can also provide and ENAV buffer configuration.
[0042] The website connection limitation information (i.e., the walled garden list”) can comprise a plurality of website addresses. The website connection limitation information is provided to the network interface 17 . Then, while the data of the I-DVD is reproduced, the website connection limitation information can be referred to by the user at a time of surfing the web, for example.
[0043] In certain embodiments, the walled garden list includes information about websites that can be accessed during the I-DVD playback. In other embodiments, the walled garden list includes information about websites that cannot be accessed during the I-DVD playback. Other implementations are also possible, where a combination of access permission or restrictions may be granted, according the content of the walled garden list.
[0044] The iDVD engine 15 confirms a version of a preloading list from the start-up file, and transmits the confirmed version information to a specified server through the network interface 17 , at step S 15 . Location information of the specified server can be confirmed from information designated in the tag “<wgarden>”, for example, or from URL information recorded in the “EnDvd.inf” file. A corresponding server receiving the version information transmits the preloading list of a latest version to the player, if the latest version higher than the received version exists in the server. In one embodiment, if the latest version higher than the received version does not exist, the corresponding server notifies the player that the received version is the latest version.
[0045] If the preloading list is downloaded, the memory unit 13 receives and stores the downloaded list. The downloaded list is used as preloading information. If the preloading list is not downloaded, the preloading list contained in the start-up file is used as the preloading information, at step S 16 . Contents recorded in the preloading list and certain ENAV data (e.g., html files, image files, sound files, text files, etc.) is stored in the memory space designated by the above-described tag “<pload>”.
[0046] The preloading list can be defined in the following formats, in one or more embodiments. Files to be preloaded can vary according to a level of a right to reproduce the data of the DVD as described below or according to a region code.
<preload> <unit no=”1”> <DATA name=”aaa” able=”TRUE”> <INDEX>2th</INDEX> <TYPE>doc</TYPE> <src t_ID=”5” t_lang=”all”>http://www.disney.com/a/b.htm</src> <src t_ID=”1” t_lang=”all”>http://www.disney.com/a/c.htm</src> </DATA> ... </unit> ... </preload>
[0047] In the above example, “unit” means a section in which the ENAV data is seamlessly reproduced along with the A/V data linked to the ENAV data. All A/V data items recorded on the I-DVD (i.e., titles) can be configured by one or more applications. One application can be linked to one ENAV unit. An additional contents item to be preloaded for each unit (i.e., an ENAV data item) is defined by a tag “<DATA>” contained in the unit. In the above example, if a playback level (parental ID) is confirmed from the start-up file (i.e., t_ID, is “5”) then a file of http://www.disney.com/a/b.htm, for example, is loaded in the memory unit 13 .
[0048] If a playback level (parental ID) is confirmed from the start-up file (i.e., t_ID, is “1”), then a file of http://www.disney.com/a/c.htm, for example, is loaded in the memory unit 13 . The file to be preloaded can be in a remote web site, according to the above-described example, but the file also can be designated as a file recorded in the specified directory of the seated disk. In some embodiments, data files for presentation of “html” files (e.g., image files), sound files, or banner files) are designated under a subsequent tag “<DATA>”, for example. **
[0049] Thus, items designated in each tag “<DATA>” are, for example, read from the seated disk or received from a remote server. The read or received items are sequentially stored in the memory unit 13 , in one embodiment. If all files designated within the unit “<unit>”, for example, for one application have been stored, a preloading operation is completed, at step S 17 . If size of files designated within the one unit exceeds, for example, 36 Mbytes described above, the preloading operation is terminated, even if the preloading operation for another unit is not completed.
[0050] In one embodiment, the iDVD engine 15 confirms, from the start-up file, a file (e.g., a setup file “index.html”) designated to be performed after the start-up file is performed. The iDVD engine 15 requests the control unit 16 to read the confirmed file from the I-DVD 10 . If the setup file is loaded in the memory unit 13 in response to the request, the iDVD engine 15 interprets the file at step S 18 , and configures and outputs an initial screen by the user's selection.
[0051] If the user selects “playback start” from the initial screen, the control unit 16 requests the iDVD engine 15 to notify it of a confirmed playback right level. The control unit 16 compares the playback right level received from the iDVD engine 15 with a playback right level set in the player. If the playback right level set in the player is lower than the playback right level confirmed from the start-up file, the control unit 16 does not perform the requested playback, and configures and outputs a message indicating that the requested playback cannot be performed.
[0052] In one embodiment, if the playback right level set in the player is not lower than the playback right level confirmed from the start-up file, the control unit 16 begins to reproduce the data of the seated I-DVD 10 . A region code set in the player is compared with a region code confirmed from the start-up file. If the region code set in the player is different from the region code confirmed from the start-up file, the playback operation is not performed. Otherwise, the playback operation can be performed.
[0053] If the playback operation is initiated, the control unit 16 buffers recorded A/V data in the memory unit 13 while driving the seated I-DVD 10 . The buffered A/V data is decoded by the DVD engine 14 so that an A/V signal can be outputted. During this operation, the iDVD engine 15 reads the ENAV data preloaded in the memory unit 13 , and performs a decoding operation to output an A/V signal. The A/V signal from the iDVD engine 15 is synthesized with an output signal from the DVD engine 14 by the synthesizer 18 . The synthesized signals are outputted externally, at step S 19 .
[0054] In some embodiments, the iDVD engine 15 refers to synchronization information (e.g., linkage information between each file name and time) recorded in a synchronization file “index.syn” to synchronize files configuring the ENAV data with A/V data being reproduced from the I-DVD 10 . When a latest version list associated with a preloading list designated in a start-up file “StartUp.mls” recorded on the I-DVD 10 is received from a remote server, a synchronization file “index.syn” is also received. The received synchronization file “index.syn” can be used in place of a synchronization file “index.syn” recorded in the I-DVD 10 .
[0055] If ENAV data units for a current application preloaded in the memory unit 13 have been outputted, at step S 20 , the iDVD engine 15 notifies the control unit 16 that some or all of the ENAV data units have been outputted. In response to the notification, the control unit 16 stops the operation of the DVD engine 14 . Then, the iDVD engine 15 refers to the above-described interpreted preloading list information, and preloads ENAV data, such as the ENAV units of a next application, in the memory unit 13 .
[0056] When a file to be preloaded matches a file preloaded in the memory unit 13 , for example, a corresponding file is not newly loaded. That is, the corresponding file is not read from the I-DVD 10 or not received from an external server. Data of a previous file stored in the memory unit 13 is used, at step S 21 , in one embodiment. The exclusion of a loading operation repeat can reduce a preloading time. If the ENAV data of next units has been loaded, then the control unit 16 is notified that the ENAV data has been completely loaded, and the playback operation is initiated from a point when it has been stopped.
[0057] The A/V data recorded on the disk and additional contents (ENAV data) associated with the A/V data are synchronized with each other and seamlessly outputted in a synchronized state. The above-described operation is continuously performed until the I-DVD playback is completed or a playback stop request is received from the user, at step S 26 .
[0058] If the user makes a specified website connection request, at step S 23 in a synchronous playback or non-playback state, the control unit 16 provides input information to the network interface 17 and requests the network interface 17 to perform a specified website connection. Then, the network interface 17 determines whether a website address for the specified website connection is contained in previously received website connection limitation information, at step S 24 . If so, the network interface 17 sends a connection request with a received address, and receives a corresponding web page to store the received web page in the memory unit 13 , at step S 25 . The iDVD engine 15 interprets the stored web page, and then a video signal is outputted on the basis of the interpreted web page.
[0059] If a website address for the specified website connection is not contained in previously received website connection limitation information, the network interface 17 confirms a current operating mode through the control unit 16 . If the current operating mode is in the non-playback state or a general DVD playback state, then an operation is performed as in the case where the website address for the specified website connection is contained in the previously received website connection limitation information.
[0060] If the current operating mode is in an I-DVD playback state, the connection to the web site based on the request is not performed. At this time, the control unit 16 outputs a message indicating that the connection to the website based on the request cannot be performed in the I-DVD playback state.
[0061] In some embodiments, this website connection limitation information is set in the start-up file “StartUp.mls” by a manufacturer of the I-DVD such that a time delay or the memory's load caused by a certain website connection can be prevented in the I-DVD playback state.
[0062] Embodiments of the invention are described by way of example as applicable to systems and corresponding methods that provide a method for processing a connection request of a disk player. In this exemplary embodiment, logic code for performing these methods is implemented in the form of, for example, application software. The logic code, in one embodiment, may be comprised of one or more modules that execute on one or more processors in a distributed or non-distributed communication model.
[0063] It should also be understood that the programs, modules, processes, methods, and the like, described herein are but an exemplary implementation and are not related, or limited, to any particular computer, apparatus, or computer programming language. Rather, various types of general-purpose computing machines or devices may be used with logic code implemented in accordance with the teachings provided, herein. Further, the order in which the steps of the present method are performed is purely illustrative in nature. In fact, the steps can be performed in any order or in parallel, unless indicated otherwise by the present disclosure.
[0064] The method of the present invention may be performed in either hardware, software, or any combination thereof, as those terms are currently known in the art. In particular, the present method may be carried out by software, firmware, or macrocode operating on a computer or computers of any type. Additionally, software embodying the present invention may comprise computer instructions and stored on a recording medium of any form (e.g., ROM, RAM, magnetic media, punched tape or card, compact disk (CD), DVD, etc.). Furthermore, such software may also be transmitted in the form of a computer signal embodied in a carrier wave, or accessible through web pages provided on computers networks such as the Internet, for example. Accordingly, the present invention is not limited to any particular platform, unless specifically stated otherwise in the present disclosure.
[0065] The present invention has been described above with reference to preferred embodiments. However, those skilled in the art will recognize that changes and modifications may be made in these preferred embodiments without departing from the scope of the present invention. The embodiments described above are to be considered in all aspects as illustrative only and not restrictive in any manner. Thus, other exemplary embodiments, system architectures, platforms, and implementations that can support various aspects of the invention may be utilized without departing from the essential characteristics described herein. These and various other adaptations and combinations of features of the embodiments disclosed are within the scope of the invention. The invention is defined by the claims and their full scope of equivalents. various other adaptations and combinations of features of the embodiments disclosed are within the scope of the invention. The invention is defined by the claims and their full scope of equivalents. | A method and apparatus for connecting a media player to a content server are discussed. According to an embodiment, the method includes determining whether a connection to a content server is required; searching control information to identity whether the connection to the content server is permitted, the control information including connection limitation information associated with a connectable content server, the connection limitation information including address of the connectable content server; and controlling the connection to the content server in response to the connection limitation information. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 60/902,334 filed 20 Feb. 2007, which hereby is incorporated herein by reference in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is directed to test equipment, and more particularly to test equipment for circuit boards.
2. Description of the Related Art
Circuit board testers are used for testing a variety of circuit boards or similar devices to assure that the circuit boards operate as intended. In at least one type of circuit board tester, such as Agilent Model No. 3070, Series 3, a separate device, referred to as a fixture, is used to position the circuit board such that a plurality of electrically conductive probes (which are part of, or coupled to, the tester) contact predetermined components or positions of the circuit board. The particular components or positions that are contacted by the test or probes depend on the tests that are desired. When the probes are in contact with the desired locations on the circuit board, electrical signals with predetermined parameters (e.g., predetermined magnitudes or patterns of current, voltage frequency, phase and the like) are applied by the tester, typically under control of a computer, to certain of the probes. Some or all of the probes are used to measure the performance or response of the circuit board (i.e., to measure electrical parameters at some or all of the probes contacting the circuit board). In this way, it is possible to rapidly perform a number of tests or measurements characterizing the performance of the circuit board while simulating the conditions the circuit board would have, or could have, during actual use. Although it is possible to use these types of tests (and testing devices) for a variety of possible purposes (such as “spot checking” selected circuit boards at a production facility, testing circuit boards which may be malfunctioning, testing prototype circuit boards as part of a design program and the like), in at least some applications, circuit board testing is used to provide quality assurance on all or substantially all products of a given type or class which are produced by a company. Even with the relatively rapid test procedures which can be achieved by circuit testing, it is not unusual for desired testing of each circuit board to require on the order of 30 seconds to 90 seconds or more.
Because, in at least some applications, circuit board testing is performed on substantially all devices on a production line or production facility, speed and reliability of testing can be especially important since delay or failure at a testing station can delay or interrupt the overall production in a production line or facility. Accordingly, it would be useful to provide a fixture, useable in connection with in-circuit testers, which provides desired speed of positioning the circuit board or other unit under test (UUT) and which achieves a relatively high degree of reliability, e.g., so as to avoid interrupting or delaying production rates at a production line or facility.
The effect of such testing on overall production rates is at least partially related to the rate at which each UUT can be placed in the fixture and the rate at which the fixture can accurately and reliably move the UUT to the desired position or positions.
One arrangement is that it has a test bed of probes on a base and a hinged cover carrying the UUT bolted into the upper hinged portion of the test device. This configuration depends upon perfect alignment of the UUT and the test bed. Such perfect alignment is not always achievable and much work is required to realign the UUT and the probe bed for perfect mating. Furthermore, the circuit boards (UUT) themselves vary somewhat from unit to unit making successive tests problematic without realignment.
BRIEF SUMMARY OF THE INVENTION
The present invention relates to a system and method for insuring alignment of a probe plate with a unit under test (UUT) by bringing physical and electrical contacts into reliable and repeatable alignment even where there are expected shifts between the probe plate/array and the UUT.
The following are some of the features of the invention.
There is disclosed a circuit tester for testing circuit boards having a housing having first and second parts hinged together; a first board mounting plate affixed to the first part of said housing; a probe plate attached to the second part of said housing, said plate having at least one probe, at least one of said plates being slideably attached to said housing to permit lateral shifting thereof; at least one aligner between said board mounting plate and said probe plate for bringing said probe plate into desired alignment with said board when said first and second parts are hingedly brought together; said aligner including a bolt attached to one plate and a bolt receiving element attached to the other, and wherein said bolt receiving element includes an aperture larger than the bolt, so that the plates may move relative to each other, and further including a further pin on one plate and fixed alignment receiver which when brought together they align the two plates.
A further feature of the invention is having the pin including a distal end which is chamfered to aid in mating with said aperture in said receiver.
A further feature of the invention is herein said bolt is round and of a predefined diameter and wherein said aperture in bolt receiving element has a diameter larger than said predefined diameter, thereby defining a gap.
A further feature of the invention is wherein said gap is generally equal to the degree of lateral movement of one of said plates.
A further feature of the invention is wherein said bolt has a threaded portion an unthreaded shoulder portion and a head portion.
A further feature of the invention is including at least to aligners, and wherein said aligners are located in different quadrants of the plates.
A further feature of the invention is wherein said aligner further includes:
at least one aperture on said plate which includes said pin, a shoulder bolt of dimension smaller than said aperture.
A further feature of the invention is a circuit tester for testing circuit boards having a housing having first and second parts hinged together; a first circuit board mounting plate affixed to the first part of said housing; a probe plate attached to the second part of said housing, said plate having at least one probe capable of contacting the circuit board; at least one of said plates being mounted to said housing by a plurality of bolts received within receivers of diameter larger than said bolts lateral shifting thereof generally equal to the differential between the bolt diameter and the receiver diameter, at least two alignment elements located on different quadrants of the plates, between said board mounting plate and said probe plate for bringing said probe plate into desired alignment with said circuit board when said first and second parts are hingedly brought together; said aligner including a fixed pin on one plate and fixed alignment receiver, said pin and said receiver being of generally the same size so that when brought together they align the two plates.
A further feature of the invention is wherein the alignment receiver includes an aperture for receiving said pin and further includes a position adjuster capable of adjusting the position of the aperture.
A further feature of the invention is wherein said position adjuster includes a pair of screw adjusters, one for x and y axes.
Another feature of the invention is a method of precisely aligning a circuit board with a probe plate comprising the steps of: mounting the circuit board or probe plate on either side of a hingable housing; providing slideable engagement of either the probe plate or circuit board with respect to its side of the housing; proving an engageable aligner between the plate and circuit board, bringing the two boards together precisely aligning the boards just before the moment of contact.
It is to be understood that this summary is intended only to assist the reader in preparing to understand the invention as described below and is not intended to limit the scope thereof in any way. The scope of protection of the invention is defined by the claims which follow this disclosure.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a perspective view of a circuit board tester in open position.
FIG. 2 illustrates a schematic view of a circuit board tester in test position looking downwardly from the top, with portions broken away;
FIG. 3 illustrates a schematic view looking at the probe plate, UUT, and support plates from the top down;
FIG. 4 is a schematic view of the support plate and UUT with the probe plate removed, from top down;
FIG. 5 is a schematic of a side view of a probe plate and associated hardware with registration blocks of the bottom support plate shown;
FIG. 6 is side plan view in section, with portions broken away illustrating shoulder bolts, registration pins and registration blocks;
FIG. 7 is a view of a portion of FIG. 6 showing a close up of a shoulder bolt and stand off in place on a probe plate;
FIG. 8 is a top perspective of a registration bolt and block approaching engagement;
FIG. 9 is a bottom perspective view of a registration bolt and block engaged;
FIG. 10 is a top plan schematic view of a registration block;
FIG. 11 is a side perspective view of an adjustable registration block; and
FIG. 12 is another side perspective view of the block in FIG. 11 showing adjustment screws and a portion of the bottom.
DETAILED DESCRIPTION OF THE INVENTION
In a manufacturing environment for circuit boards, a final test will often be an electrical test, to ensure that each circuit board performs as required. Such tests are well-known in the industry, and may be performed by commercially available testers, such as Agilent Model 3070.
A detailed view of the mechanical configuration is shown in FIG. 1 . The UUT (unit under test) is shown as a circuit board 16 and is removably and rigidly attached to, and optionally, spaced apart from, a support plate or mounting plate 18 with or without spacer elements. In this configuration, the electrical contacts on the UUT 16 that are to be tested face upward, and are accessible by various probes on plate 18 . There may also be probes from underneath the UUT 16 . In this case, probes from the top are illustrated. Note that the circuit board and fixture on which it is mounted are considered one for the purpose of this application, though they are likely to be separate components. One of the issues resolved by this invention is relative movement between the board and the probes. We refer to the circuit board whether or not it includes a fixture. The probes may apply and measure voltages or currents at various locations on the UUT, and are controlled mechanically and electrically by the tester. A computer, not shown, may control the tester and may record data from the tests.
The testing system 10 is shown as a box with a top 12 with handle 20 holding a probe plate 22 . Probe plate 22 is configured to be freely moveable in lateral directions and optionally to a limited degree along a vertical axis which passes orthogonally thru the UUT 16 and probe plate 22 when the box is closed.
The bottom of the system 10 includes a support plate 18 which supports the UUT 16 preferably rigidly in place on plate 18 . There are several ways to accomplish this rigid connection. The preferred way is by posts 30 which surround the UUT and create a rigid perimeter. The posts may engage notches in the UUT board, but they may also simply be placed around the periphery to inhibit movement. In some circumstances, the UUT may have existing apertures which allow it to be affixed to the support plate.
Hinges 24 allow the top 12 and support 18 to move relative to each other. Pneumatic cylinders 24 , regulate the movement of the top and plate.
Fundamentally, there is a problem where the probe plate and UUT are not perfectly aligned. This can occur for many reasons, none of which can be fully anticipated. Therefore, a simple way to align the UUT with the probe plate immediately before engagement is highly desirable. Thus a system and method which causes alignment at the last moment before contact is preferable to any other system because earlier alignment my not be sustainable in the remaining travel toward contact. In the present invention, means are provided to allow the plate on which the UUT or the UUT itself to be secured in the housing but to float/shift laterally in response to alignment means and devices which are provided on the plate or UUT. Note that either the UUT, the (circuit) board, or the probe plate can be allowed to float. It is only important that one can float or move laterally to make the alignment possible. These aligners (or alignment blocks in the preferred embodiment) take advantage of the lateral translation capability of the UUT and as the test cover is being closed, make final and precise alignment. Thus, the fasteners which allow the UUT to float may be of many designs, not just the few which are detailed in this disclosure. In the preferred embodiment there will be at least 2 alignment blocks in different quadrants of the plates (the plate having an imaginary division of 4 quadrants). It would be best to put the blocks in diagonally opposite quadrants if only two are used. One can be used but with less precision or if the alignment bold it a bar type structure which will cause alignment along its face so that both x and y axes are aligned simultaneously by one aligner. This is not preferred however because it is difficult to align such a bar.
The lateral and vertical adjustability (movement) to the probe plate (or the UUT if reversed) is obtained by several mechanisms. The probe plate is slideably affixed to its housing 14 on shoulder bolts 32 . FIG. 6 is side plan view in section, with portions broken away illustrating shoulder bolts, registration pins and registration blocks.
FIG. 7 is a view of a portion of FIG. 6 showing a close up of a shoulder bolt and stand off in place on a probe plate. This allows the probe plate to move laterally to align its alignment pins 40 on alignment blocks 28 (i.e., aligners or alignment means). In this embodiment there are two such blocks. There can be any number greater than two in the preferred configuration. Shoulder bolts, or bolts, are just one kind of fastener which will allow lateral play while limiting vertical movement (if desired, as is the case here). They need not be cylindrical or “bolts” in the common meaning of the term, but only provide a guide attached to one (either) of the plates. The key is to create play or float in the gap between the bolt's outside dimension and the receiving blocks's bore in which it is received during the alignment phase.
FIG. 2 illustrates a top view of the system in test position and FIG. 3 illustrates the system in test position with the top housing 14 overlying the base and support plate 18 with the UUT 16 sandwiched between the probe plate 22 and support plate 18 . Four shoulder bolts 32 are shown. Alignment bolts 40 are shown engaged in alignment blocks 28 . FIGS. 4 and 5 are similar views of these objects. FIG. 3 illustrates a schematic view looking at the probe plate, UUT, and support plates from the top down, and FIG. 4 is a schematic view of the support plate and UUT with the probe plate removed, from top down.
FIG. 5 is a side view of the probe plate 22 with shoulder bolts 32 in place. Bolts 32 are preferably threaded into standoffs which hold the probe plate spaced from the housing 14 . They are preferably rigidly affixed to the house by additional fasteners (not shown). The standoff will be of whatever length is required to insure proper mating of the housing and probe plate with the underlying UUT.
FIGS. 6 , and 7 illustrate the feature and functions of the shoulder bolts 32 . Each shoulder bolt includes a head 70 , a shoulder portion 72 and a threaded portion 74 which is threaded into the standoff. The probe plate includes apertures 60 which has a slightly greater diameter (or cross section if not round) than shoulder portion 72 . This gap 62 provides the lateral movement of the probe plate relative to the housing 14 and the UUT 16 . Note that lesser of gap 62 or 64 (surrounding the head 70 ) will control the lateral movement. Since the shaft of the bolt is longer than the head, gap 62 which surrounds the shaft is typically the one which is used to control the float. Thus gap 64 is necessarily larger, but the reverse could also be employed. It is also advisable that the head 70 be recessed by counterboring 68 to prevent the head from inhibiting lateral movement.
With the probe plate capable of lateral movement (i.e., movement parallel to the UUT when in test position and orthogonal to bolts 32 ), it is the mating of alignment bolt or pins 40 into alignment blocks 28 which control the precise alignment of the probe plate and UUT.
FIGS. 8 , 9 and 10 illustrate this mating. The alignment bolt or pin is precisely secured to the probe plate and the block 28 is likewise precisely secured to the support plate. The engagement end 80 of the pin 40 is preferably chamfered or rounded at its distal end to aid in engagement. Likewise the alignment block 28 includes a preferably hardened bushing 84 with a central aperture, which may also be rounded/chamfered at its receiving end of more easily mate with pin 40 when they are misaligned, as they are expected to be. The block preferably has mounting apertures 86 with cut away portions to recess fasteners. On the bottom side ( FIG. 9 ) are preferably pins 88 which mate with recesses in the support plate to further insure precise alignment. Chamfering or rounding may be important because of the geometry of hinges. They path of the housing as it closes, follows and arc so that it is the pin and receiver with not be arriving co-linearly aligned, but askew. The chamfering prevents the elements from colliding in such a way as to freeze the movement of either.
It will be appreciated that errors can occur in the placement of the pins 40 or block 28 , or for other reasons, alignment is not perfect. To avoid having to rebuild the tester altogether, it is possible to modify alignment blocks 28 so that their bushings 84 compensate for slight errors. This is accomplished by drilling the mounting hole for the bushing off center, or by drilling the central aperture in the bushing off center. Thus a method of manufacture and/or use of this invention includes the step of alignment of the pin and block by alteration of the block to accommodate precise alignment.
FIGS. 11 and 12 illustrate another of many ways to compensate for alignment errors. Block 28 a is similar to block 28 in its function except that it includes adjusters 90 , 92 which cause the block stock 100 , 102 , 104 to slide relative to each other. The blocks 100 , 102 , 104 are slideably interlocked to their adjacent block by dovetail interlocking grooves or cuts which are capable of sliding past each other. The sliding action for each pair of blocks is controlled by set screws 90 and 92 which drive nuts (not shown) inside the blocks which are attached to the blocks and cause lateral movement in X or Y axis (depending on the screw). In effect, the blocks include a rack and pinion style drive which allow bushing 84 to be shifted in any of four directions or combinations thereof. Other structures which allow for the central axis of the bushing to be moved, will accomplish this inventive concept of allowing for precision adjustment. This concept, i.e. having the alignment blocks themselves be alignable may be used together with the other concepts of this disclosure or singly. Furthermore, this concept is not limited to the rack and pinion solution shown, but any solution which would allow adjustment of the position of the aperture 84 relative the surface upon which it is mounted. For example, another solution would be to drill hole 84 off center (though not adjustable). A further solution would be to provide apertures 86 ( FIG. 10 ) to be elongated or to be screw adjustable, to allow shifting of the position of the block.
It will be appreciated that while the preferred embodiment is to adjust the probe plate relative to a fixed UUT, the opposite arrangement is likewise possible with lateral movement being permitted in the UUT circuit board or both, by providing means such as shoulder bolts to both. The alignment blocks may recessed as shown in FIG. 3 to allow greater clearance for probes and testers or the blocks may be installed on the top unit or probe plate itself. Furthermore, it is possible to have double alignment from above and below the UUT. If the UUT is likewise mounted on a lateral shifting mechanism, such as the shoulder bolts shown, then a probe plate from above can also be located below and the UUT can be tested on both sides simultaneously with precision alignment of both sides being possible.
The forgoing disclosure is not intended to be a limit to the scope of the invention. The claims define the scope and should be interpreted broadly. | A circuit board tester and method that precisely aligns the probe plate and circuit board is disclosed. With a circuit board and probe plate mounting within a housing having a top and bottom, hinged together, at closure there may be slight misalignments of the two. By making one of the two plates floating, or laterally slideable with respect to each other, it is possible to make final alignment at closure. One of the two plates can be provided with a pin and the other with a pin receiving alignment block. With the lateral sideability, the pin and block can insure proper probe alignment. Additional systems for correcting misaligned pins or blocks are also disclosed. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to a zero-emission renewable heating system utilizing a thermal energy capacitor system using solar power as its source of heat, and more particularly, to a solar thermal capacitor system using an solar concentrators and a molten salt cell with thermal storage capability.
BACKGROUND OF THE INVENTION
[0002] The desire to decrease and ultimately eliminate dependence on limited energy resources has stimulated research into clean and renewable ways to conserve resources and utilize renewable energy sources. Solar power has become a viable option because it is a clean form of energy production and there is a potentially limitless supply of solar radiation. To that end, it is estimated the solar energy flux from the sun is approximately 2.7 megawatt-hours per square meter per year in certain advantageous areas of the world. With this tremendous amount of free and clean energy available, and the desire to reduce dependence on limited resources, solar power production is now, more than ever, being reviewed as an important means to help meet the energy consumption demands in various parts of the world.
[0003] Molten salt is used in solar power tower systems because it is liquid at atmosphere pressure, it provides an efficient, low-cost medium in which to store thermal energy, its operating temperatures are compatible with todays high-pressure and high-temperature steam turbines, and it is non-flammable and nontoxic. In addition, molten salt is used in the chemical and metals industries as a heat-transport fluid, so experience with molten-salt systems exists for non-solar applications.
[0004] Molten salt is also an efficient heat capacitor, with low heat dissipation. It retains thermal energy very effectively over time and operates at very high temperatures. It is relatively inexpensive and plentiful, and generally non-toxic. Thermal storage is widely regarded as the future for the renewable energy campaign because, unlike many intermittent renewable resources such as wind energy, it offers a “zero-emissions” technology.
[0005] Several molten salt heat transfer fluids have been used for solar thermal systems. The binary Solar Salt mixture was used at the 10 MWe Solar Two central receiver project in Barstow, Calif. It will also be used in the indirect TES system for the Andasol plant in Spain. Among the candidate mixtures, it has the highest thermal stability and the lowest cost, but also the highest melting point. Hitec HTS® has been used for decades in the heat treating industry. This salt is thermally stable at temperatures up to 454° C., and may be used up to 538° C. for short periods, but a nitrogen cover gas is required to prevent the slow conversion of the nitrite component to nitrate. The currently available molten salt formulations do not provide an optimum combination of properties, freezing point, and cost that is needed for a replacement heat transfer fluid in parabolic trough solar fields. Therefore, the work summarized in this report sought to develop an heat transfer fluid that will better meet the needs of parabolic trough plants.
[0006] In many areas of the world, thermal energy for heating and cooking use coal or wood or such other resource. These resources generally are not renewable and emit significant waste. Accordingly, a need exists for a thermal energy generation system capable of efficient energy collection, with high temperature capability, and with the ability to store collected energy in areas where resources are extremely limited.
SUMMARY OF THE INVENTION
[0007] The present invention is directed to a solar power thermal energy capacitor capable of storing heat energy wherein sun light is converted to thermal energy. The solar power system includes a solar concentrator system, which concentrates the sunlight onto thermal capacitor. The concentrated sunlight heats a surface of the thermal capacitor.
[0008] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:
[0010] FIG. 1 is a schematic of a solar thermal capacitor system according to a preferred embodiment of the present invention;
[0011] FIG. 2 is a schematic of an alternate solar thermal capacitor system according to a preferred embodiment of the present invention;
[0012] FIG. 3 is a drawing of a linear Fresnel concentrator and a linear thermal capacitor;
[0013] FIG. 4 depicts variations of mirror concentrators as the solar concentrator component;
[0014] FIG. 5 a schematic of an alternate solar thermal capacitor system having multiple solar concentrators according to a preferred embodiment of the present invention;
[0015] FIG. 6 depicts variations of thermal capacitor cells;
[0016] FIG. 7 is a sectional perspective of a solar thermal capacitor system;
[0017] FIG. 8 illustrates a stand-alone system utilizing a large Fresnel lens to heat thermal capacitor according to the teachings of the present invention;
[0018] FIG. 9 is a schematic of a solar thermal capacitor system having multiple collection systems according to the teachings of the present invention;
[0019] FIG. 10 is a schematic of a solar thermal capacitor system illustrating the tracking of the sun by the system according to the teachings of the present invention;
[0020] FIG. 11 is a schematic of an alternate solar thermal capacitor system having multiple collection systems according to the teachings of the present invention;
[0021] FIG. 12 is a schematic of a complete solar thermal capacitor system capable of tracking the sun according to the teachings of the present invention;
[0022] FIG. 13 illustrates the use of a solar thermal capacitor system during the day and night in a house for cooking and heating according to the teachings of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
[0024] With reference to FIG. 1 , a solar thermal capacitor system 10 in accordance with a preferred embodiment of the present invention is shown. The solar thermal capacitor system 10 includes a solar collection system 12 and a thermal capacitor 16 . The solar collection system 12 gathers sunlight and concentrates the sunlight to a thermal capacitor 16 . The thermal capacitor 16 uses molten salt 14 to store the thermal energy from the solar collection system 12 .
[0025] The solar collection system 12 has a solar concentrator 18 . The solar concentrator 18 gathers sunlight and concentrates the sunlight. The solar concentrator 18 includes a lens 22 or a mirror. In one preferred form, the lens 22 is a Fresnel lens ( FIG. 1 ) or a magnifying lens ( FIG. 2 ). The sunlight strikes the lens 22 and is focused onto the thermal capacitor 16 below the lens 22 . The lens 22 is coupled to a support structure 26 that supports the lens 22 and operably coupled to a base. The thermal capacitor 16 can be independent of support structure 26 ( FIG. 1 ) or dependent from the support structure 26 ( FIG. 2 ).
[0026] The concentrating component (interchangeably referred to also as lens or mirror) 18 , which can help focus the spatially decomposed solar spectrum onto the thermal capacitor 16 , can be provided in any number of useful configurations. Preferred designs utilize optical lens to concentrate diffracted light.
[0027] The optical component used in the solar concentrators typically provides a 2-10000 fold concentration, more preferably 5-1000, more preferably 10-500-fold concentration of the sun irradiance, most preferably greater than a 10-fold concentration. The concentrator can take different forms such as, but not limited to, rectangular, polygonal or circular shapes (including arcs, cylinders, semi-cylinders, planes, etc), and can be made of any suitable materials. Concentrators can include, e.g., a convex lens (both biconvex and plano-convex), positive or negative meniscus lens, a gradient refractive index lens, a Fresnel lens, standard magnifying lens, or other type of light concentrating lens, and/or the like (see FIG. 2 ). The choice of lens can be influenced by design requirements such as aspect ratio, weight, cost and the reliability desired in the concentrator structure, as further described below.
[0028] Concentrator 18 is mounted on the very top of the assembly and concentrates the light energy from the sun through top aperture. The concentration of the light energy need not be at a focal point when entering the aperture. The lens may be a standard magnifying lens ( FIG. 2 ), a Fresnel type lens ( FIG. 1 ) or other type of light concentrating lens and may be round, elliptical, semi-elliptical ( FIG. 3 ), rectangular (or rectangular with rounded edges), triangular, or irregular in general shape when looking at the direction of the light path (from the side). The lens is designed to fit the top of the assembly as well as focus as much light on the thermal capacitor 16 of the device. The lens can take the general structure of the housing or be embedded within the housing ( FIG. 2 ).
[0029] The shape of the concentrator can be modified to adjust the concentration and direction of the light energy to optimize its use so as to increase efficiency and maximize heat generation. In one embodiment, the lens 22 in FIG. 3 is shaped to concentrate the sunlight linearly creating a focal line at the top of the thermal capacitor 16 or off-focus below the thermal capacitor. More preferably, the concentrator will concentrate the light at the top of the thermal capacitor 16 to generate maximum heat.
[0030] With reference to FIG. 4 , the focal length of a lens in air can be calculated from the lensmaker's equation:
[0000]
1
f
=
(
n
-
1
)
[
1
R
1
-
1
R
2
+
(
n
-
1
)
d
n
R
1
R
2
]
,
[0031] where
[0032] f is the focal length of the lens,
[0033] n is the refractive index of the lens material,
[0034] R1 is the radius of curvature of the lens surface closest to the light source,
[0035] R2 is the radius of curvature of the lens surface farthest from the light source, and
[0036] d is the thickness of the lens (the distance along the lens axis between the two surface vertices).
[0037] To increase the incident light's intensity you have to change material (higher refractive index) or decrease the focal length increasing the lens curvature (higher aberrations) or increase the optical quality.
[0038] By example and without limitation, the concentrator is formed of glass, acrylic, silicone, plastic, polycarbonate, or fluoropolymers (e.g., Ethylene Tetrafluoroethylene (ETFE), or another transparent material to have a focal length structured for focusing or concentrating the light energy from the sun through top aperture. Preferably, solar concentrator is formed of material with thought to such attributes as resistance to warping or corrosion, breaking, cracking, scratching, shattering, melting, extreme heat, oxidation and discoloration; little light absorption or loss; heat absorption, low cost, ease of manufacturing, strength, weight, availability, toxicity, magnification, regional availability of resources and manufacturing capabilities, combinations thereof, and the like. For example, ETFE film is utilized in a one embodiment of the present invention as it is 1% the weight, transmits more light and costs 24% to 70% less to install compared to glass. Commercially deployed brand names of ETFE include Tefzel by DuPont, Fluon by Asahi Glass Company, Neoflon ETFE by Daikin, and Texlon by Vector Foiltec.
[0039] In other embodiments of concentrator components, concentrators are assembled from cast components, such as cast acrylic or other polymer (e.g., acrylate, methacrylate, polyethylene terephthalate (PET), polycarbonate) or a combination of cast components and extruded components or from optical components manufactured by various other manufacturing processes. Exemplary cast acrylic components include HESA-GLAS from Notz Plastics AG and available from G-S Plastic Optics located 23 Emmett Street in Rochester, N.Y. 14605. In an alternate embodiment, solar concentrators are manufactured from extrudable material such as various plastics e.g. Fluoroplastic, Fluoropolymer or Fluorocarbon. Exemplary extruded plastics include extruded acrylics and extruded polycarbonates available from Bay Plastics Ltd (United Kingdom). Lenses can be created using known techniques, including traditional polishing or computer-controlled milling equipment (CNC) that can turn out large complex pieces from single pieces of glass. Exemplary lens manufacturers include Kenteh Optical Co., Ltd. (Taiwan) and E-Tay Industrial Co., Ltd. (Taiwan), WuXi Bohai Optical Apparatus Electronic Co., Ltd. (China), Wenzhou Mingfa Optics Plastics Co., Ltd. (China), CDGM Glass Co., Ltd. (China), Ikeda Lens Industrial Co., Ltd (Japan), etc.
[0040] Other choices of concentrators can include mirrors that reflect sunlight unto a single point or points (See FIG. 4 ), such as with a) linear parabolic mirrors; b) compound linear fresnel mirrors; c) compound parabolic mirror(s); d) mirror array; e) compound hyperbolic mirrors; f) compound elliptic mirrors; and the like. These contractors can have a second concentration stage to further improve the quality or magnitude of concentration.
[0041] As shown in FIG. 5 , multiple lenses 22 and 24 can be employed in series to refract the light through each layer of lens. Each layer refracts the light 26 and reduces the distance between the 1st lens 22 and the thermal capacitor 16 .
[0042] The sunlight is concentrated from the solar concentrator system 18 to the thermal capacitor 16 as shown in FIG. 2 . The concentrated sunlight 14 heats the thermal capacitor 16 directly or through an absorber 30 . As shown in FIG. 6 , the thermal capacitor can be various shapes, but is preferably in a shape that is portable and modular. Such shapes include cylindrical ( FIGS. 6A and 6B ), spherical, a block ( FIG. 6C ), cube, disc ( FIG. 6D ), rectangular ( FIG. 6E ), and other such shapes that lend the thermal capacitor to be transferred between different applications. For cost purposes, the cell can be a can and shaped accordingly.
[0043] In a preferred embodiment, solar collection system 12 can concentrate sunlight unto the entire thermal capacitor 16 or a portion thereof. As shown in FIGS. 1 and 2 , the upper portion of the thermal capacitor is an absorptive material 30 . The absorptive material 30 absorbs the solar energy and aids in the distribution of the resulting thermal energy to the molten salt 14 . The absorptive material 30 may include, for example, metal, graphitic absorbers or heat absorbers, including IR or UV absorbers. The absorber 30 can be as simple as coloring the top a heat absorbing color (e.g., black or other dark color) to a heat transmission tube 32 that transmits the heat throughout the thermal capacitor 16 . Heat tubes 32 can be used to receive the thermal energy from the absorption of concentrated sunlight and transfer the energy into the molten salt 14 .
[0044] Infrared absorbing materials and coatings are well known in the art (see, e.g., U.S. Pat. App. No. 20090029057 and WIPO Patent Application WO/2008/071770). For example, a conductive silver coating which, when during the thermal fusing (firing) of the coating to a metal, glass, silicon, polymer, ceramic or ceramic glass enamel substrate, provides infrared absorption properties over an extended temperature range. Other materials include nanoparticle coatings. Depending on the infrared absorption resonance wavelength (i.e. the wavelength at which the nanoparticles primarily absorb) and the width of the absorbance range (i.e. the wavelength range over which the nanoparticles cause absorption), one can divide nanoparticles in different groups. A first group of nanoparticles absorbs infrared energy in a broad band in the wavelength range above 1000 nm. Examples comprise indium oxide, tin oxide, antimony oxide, zinc oxide, aluminum zinc oxide, tungsten oxide, indium tin oxide (ITO) nanoparticles, antimony tin oxide (ATO), antimony indium oxide or combinations thereof. A second group of nanoparticles absorbs infrared in the near infrared. The nanoparticles of the second group absorb infrared in the range 780-1000 nm. Examples of nanoparticles of the second group comprise hexaboride nanoparticles, tungsten oxide nanoparticles or composite tungsten oxide particles. Alternatively, a metal or other conductive material can be used to absorb heat generated by infrared. IR can cause substantial heat and absorbance of the IR can be dissipated through the housing by this method. Accordingly, infrared-absorbing materials can be placed on an outermost layer of the housing wall, preferably outside or exterior to the refractor component, more preferably on a metal, glass or other material layer.
[0045] The thermal capacitor 16 can be further surrounded by an insulation layer 34 that reduces heat loss to the atmosphere and facilitate handling of the thermal capacitor 16 by a tool or by hand. The insulation layer 34 enables the thermal capacitor 16 to maintain temperature even if the sunlight has diminished or the thermal capacitor 16 is exposed to colder temperatures. Preferably, the insulation is rugged and resistant to rough environmental conditions.
[0046] Referring to FIG. 6 , the molten salt fuel 14 is stored in a thermal capacitor cell 40 , which acts to contain molten salt fuel 14 . Thermal capacitor cell 40 can be lined with an insulation layer 34 . Thermal capacitor cell 40 is capable of withstanding high temperatures, for example, temperatures of at least approximately 1200 degrees Fahrenheit (° F.), preferably at least approximately 1500° F., more preferably at least approximately 2000° F., and most preferably at least approximately 2500° F. Preferably, thermal capacitor cell 40 is resistant to corrosion and repetitive fluctuations in heat. Suitable materials for constructing thermal capacitor cell 40 include, but are not limited to: copper based alloys, nickel based alloys, iron based alloys, and cobalt based alloys, but also include such compounds such as aluminum, nickel, iron, titanium, stainless steel, or other metal or alloy. Examples of suitable commercially available nickel based alloys include: Hastelloy X, Hastelloy N, Hastelloy C, and Inconel 718, available from Special Metals Inc., Conroe, Tex. Examples of suitable commercially available iron based alloys include: A-286 and PM2000, available from Metallwerke Plansee, Austria. An example of a suitable commercially available cobalt based alloy includes: Haynes 25, available from Haynes International Inc., Windsor, Conn. Other compounds include ceramics or refractory materials, or other such compound. Preferably the material is common and cheap to manufacture or use. The thermal capacitor may have a barrier layer to reduce corrosion, for example a barrier layer comprising tungsten (W), platinum (Pt), titanium carbide (TiC), tantalum carbide (TaC), titanium oxide (for example, TiO2 or Ti4O7), copper phosphide (Cu2P3), nickel phosphide (Ni2P3), iron phosphide (FeP), and the like, or may comprise particles of such materials, preferably which is still capable of transferring heat.
[0047] The products of high temperature corrosion can potentially be turned to the advantage of the engineer. The formation of oxides on stainless steels, for example, can provide a protective layer preventing further atmospheric attack, allowing for a material to be used for sustained periods at both room and high temperature in hostile conditions. Such high temperature corrosion products in the form of compacted oxide layer glazes have also been shown to prevent or reduce wear during high temperature sliding contact of metallic (or metallic and ceramic) surfaces.
[0048] Plating, painting, and the application of enamel are the most common anti-corrosion treatments. They work by providing a barrier of corrosion-resistant material between the damaging environment and the (often cheaper, tougher, and/or easier-to-process) structural material. Aside from cosmetic and manufacturing issues, there are tradeoffs in mechanical flexibility versus resistance to abrasion and high temperature. Platings usually fail only in small sections, and if the plating is more noble than the substrate (for example, chromium on steel), a galvanic couple will cause any exposed area to corrode much more rapidly than an unplated surface would. For this reason, it is often wise to plate with a more active metal such as zinc or cadmium.
[0049] Other methods for providing corrosion protection include anodizing, controlled permeability formwork, cathodid protection methods, and the like.
[0050] Possible molten salts 14 that can be used include both pure inorganic and organic materials, and eutectic and non-eutectic mixtures. Such materials could have cationic or positively charged components such as alkali metals, alkaline earth metals, aluminum, gallium, indium, germanium, tin transition metals, lanthanide metals, phosphonium, ammonium, sulfinium, arsenium, and stibium ions including polyalkyl and polyaryl substituted species. The anionic or negatively charged components could include halides, oxides, sulfides, nitrates, carbonates, carboxylates, silicates, aluminates, sulfates, phosphates, arsenates, borates, alkoxides, and aryl and alkyl sulfonates.
[0051] The molten salt medium 14 of solar thermal capacitor 16 is a molten salt capable of being heated to high temperatures. The molten salt used in the thermal capacitor is capable of being heated to high temperatures, for example, to a temperature of at least approximately 1200 degrees Fahrenheit (° F.), preferably at least approximately 1500° F., and more preferably at least approximately 1700° F., or above approximately 1800° F. Most preferred are salts that are not liquid at ambient temperature, but salts that are liquid (having a melting point) above ambient temperature, e.g., non-ionic liquids. Alternatively, molten salt used in the thermal capacitor are salts that have melting points above ambient temperature. Inspection of published phase diagrams revealed that ternary mixtures of NaNO3 and KNO3 with several alkali and alkaline earth nitrates have quite low melting points. The eutectic of LiNO3, NaNO3 and KNO3 melts at 120° C., while a mixture of Ca(NO3)2, NaNO3 and KNO3 melts at about 133° C. Several eutectic systems containing three constituents are liquids as low as 52° C. Other salts, are for example, low-melting point salts described in U.S. Pat. No. 7,588,694 (incorporated herein).
[0052] The molten salt can be salts composed of alkaline earth fluorides and alkali metal fluorides, and combinations thereof. Suitable elements of the molten salt include: Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), Francium (Fr), Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), Radium (Ra), chlorine (Cl), bromine, iodine, Cyanide, Hydroxides, Nitrates, and Fluorine (F).
[0053] Common salt-forming cations include:
Ammonium NH4+
Calcium Ca2+
Iron Fe2+ and Fe3+
Magnesium Mg2+
Potassium K+
Pyridinium C5H5NH+
[0054] Quaternary ammonium NR4+
Sodium Na+
[0055] Common salt-forming anions (parent acids in parentheses where available) include:
[0000] Acetate CH3COO− (acetic acid)
Carbonate CO32− (carbonic acid)
Chloride Cl− (hydrochloric acid)
Citrate HOC(COO—)(CH2COO—)2 (citric acid)
Cyanide C≡N− (N/A)
[0056] Nitrate NO3− (nitric acid)
Nitrite NO2− (nitrous acid)
Phosphate PO43− (phosphoric acid)
Sulfate SO42−(sulfuric acid)
[0057] Examples of suitable fluoride molten salts include, but are not limited to: FLiNaK, FLiBe, FLiNaBe, FLiKBe, and combinations thereof. The salt can further contain a metal such as scandium, yttrium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, technetium, rhenium and lanthanoid.
[0058] In a preferred method, the present invention is directed to a molten salt bath including at least two types selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, and barium; at least one type selected from the group consisting of fluorine, chlorine, bromine, cyanide, and iodine; at least one element selected from the group consisting of scandium, yttrium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, technetium, rhenium and lanthanoid (hereinafter, this element may also be referred to as “heavy metal”); and an organic polymer including at least one type of a bond of carbon-oxygen-carbon and a bond of carbon-nitrogen-carbon.
[0059] In one embodiment, molten salts preferred are salts that are readily available, cheap, and bountiful, for example rock or halite salts, or salts primarily composed of sodium chloride (generally, having a melting point greater than 801° C., or 1474° F.).
[0060] In an alternative embodiment, the molten salt 14 is a 60/40 mixture of sodium and potassium nitrate, commonly called saltpeter. The salt melts at 430° F. and is kept liquid at 550° F. in an insulated thermal capacitor cell. However, the molten salt 42 could also be a salt carbonates (e.g., Na2CO3, sodium carbonate & other carbonates of lithium, potassium, etc.). Alternative salts include combinations of nitrates (e.g., potassium (KNO3), Sodium (NANO3)) and nitrites (e.g., sodium (NaNO2), K—Na—Ca Nitrate mixtures, a Eutectic mixture (46:24:30) with a melting point of 160° C.; K—Na—Li Nitrate Mixture with a melting point as low as 120° C., HITEC, a combination of NaNO2, NaNO3, KNO3 (40:7:53) with a melting point of approximately 142° C.; or 45.5 wt % potassium nitrate (KNO3) and 54.5% sodium nitrite (NaNO2), and the like.
[0061] The thermal capacitor cells 40 are surrounded by an insulation layer 34 or insulation barrier (e.g., structure) that reduces heat loss to the atmosphere. In particular, high wind speed contributes to heat loss, as the high winds produce convective losses, and a recessed structure is preferable.
[0062] In a preferred embodiment, the molten salt 14 in the thermal capacitor 16 is capable of retaining heat for several hours if not several days. The salt liquefies upon reaching at or above it's melting point. If the concentrated sunlight is sufficient, the salt will liquefy to become molten salt, which does not require the solar concentrator to trace the traveling sun. A concentrator 12 affixed perpendicular to the thermal capacitor 16 may be sufficient to melt the salt 14 . It may not be necessary to heat the thermal capacitor 16 throughout the day. However, in certain environments or conditions, it may be preferred for the solar concentrator 12 to follow or track the sun and heat the thermal capacitor 16 throughout the day. As shown in FIG. 7 , the solar concentrator system 18 includes a lens 22 to concentrate sunlight. The sunlight strikes the lens 22 and is focused onto the thermal capacitor 16 below the lens 22 . The lens 22 is coupled to a support structure 26 that supports the lens 22 and the thermal capacitor 16 . The support structure 26 is further coupled to a pivot assembly 28 . The pivot assembly 28 enables the lens 22 to be adjusted to track the sun as the sun travels across the sky and heat the thermal capacitor 16 . Specifically, the pivot assembly 28 provides two axes of rotation for the lens 22 , as known in the art.
[0063] In an alternate embodiment, molten salt can be any crystalline molecule that can be liquefied using solar heat. Sugars, for example are readily available and can be made into molten sugars. Preferred are compounds that can crystallize upon cooling and liquefied upon heating.
[0064] Support can be made of any material readily available and sturdy enough to support the other components, including wood, metals and the like.
[0065] As shown in FIG. 8 , the pivot assembly 28 is rotatably coupled to a base 50 . The base 50 is affixed to a ground surface and the thermal capacitors 16 remain stationary until they are needed. The lens 22 is adjusted to track the sun. The thermal capacitors 16 can be shaped to accommodate shifting focal points, e.g., multiple thermal capacitor cells, a rectangular cell or a base that can retain heat. A controller (not shown) can be coupled to the solar concentrator system 12 that controls the pivot assembly 28 so that it causes the lens 22 to track the sun across the sky. In a preferred embodiment, the base 50 holding the thermal capacitors 16 is built of heat absorbing material and/or painted to absorb heat. It may or may not be necessary to heat 50 the base to a temperature sufficient to melt the salt. In preferred embodiments, the base is built to provide further insulation to the capacitor cell, for example to encapsulate or embed 52 the thermal capacitor 16 (See FIG. 9 ). The base can be painted black and be made of heat absorbing material such as concrete or metals.
[0066] Alternatively, it may be preferred for the solar concentrator 12 to follow the sun 60 and heat the thermal capacitor 16 throughout the day. As shown in FIG. 10 , the solar concentrator system 12 includes a lens to concentrate sunlight. The sunlight 60 strikes the lens 22 and is focused onto the thermal capacitor 16 below the lens 22 . The lens 22 is coupled to a support structure 26 that supports the lens 22 and the thermal capacitor 16 . The support structure 26 is further coupled to a pivot assembly 28 . The pivot assembly 28 enables the lens 22 to be adjusted to track the sun as the sun travels across the sky and heat the thermal capacitor. Specifically, the pivot assembly 28 provides two axes of rotation for the lens 22 , as known in the art.
[0067] In yet an alternate embodiment, multiple solar concentrators can be utilized to heat multiple fuel cells 16 as shown in FIG. 11 . The rows of solar concentrator systems are constructed with thermal capacitor. FIG. 12 shows multiple lens 22 to concentrate light onto multiple thermal capacitors 16 . The lens 22 are coupled to a support structure 26 that support the lens 22 and the base 50 , which supports the thermal capacitor cells 16 . As represented in FIG. 12 , the base 50 and the lens 22 sit in parallel planes. The base 50 is affixed to a pivot assembly. The pivot assembly 28 enables the lens 22 and the base to be adjusted to track the sun as the sun travels across the sky. Specifically, the pivot assembly 28 provides two axes of rotation for the lens 22 , as known in the art. To heat the specific thermal capacitor cell, the sun must lie approximately perpendicular to the lens and base. A thermal capacitor can contain molten salt 16 b or salt that has been cooled, and likely crystallized 16 a . In an alternate system, the lens and the base are not in parallel planes. One skilled in the art will readily appreciate that the solar thermal capacitor system 10 can be scaled to accommodate a wide range of demands for solar power.
[0068] As shown in FIG. 1 , the solar concentrator system 18 includes a lens 22 or a mirror. In one preferred form, the lens 22 is a Fresnel lens. The sunlight 14 strikes the lens 22 and is focused onto the thermal capacitor XX below the lens 22 . The lens 22 is coupled to a support structure 26 that supports the lens 22 . The support structure 26 is further coupled to a pivot assembly 28 . The pivot assembly 28 is rotatably coupled to a base 50 . A controller 52 coupled to the solar concentrator system 12 controls the pivot assembly 28 so that it causes the lens 22 to track the sun across the sky. More specifically, the controller 52 drives a motor (not shown) associated with the pivot assembly 28 to pivot lens 22 as needed.
[0069] FIG. 13 shows the solar thermal capacitor system in operation over a day and evening cycle. If sufficient solar thermal condition exists, the sunlight 14 strikes the lens 22 of the solar concentrator system 12 . The lens 22 concentrates the sunlight to the focus, which is essentially at the aperture. The sunlight passes through the aperture unto the absorber 30 . The thermal energy collected by the absorber 30 is absorbed and the resulting thermal energy is transferred into the salt 14 by the heat exchanger tubes 32 . During the day, the molten salt in the thermal capacitor cells are heated to a temperature from the concentrated sunlight above the melting point of the molten salt. Some of the thermal capacitor cells will contain salt in its liquid state and other capacitor cells will contain salt not melted, in its solid or crystal form. These must be heated above the salts melting point to be used in its application. Thermal capacitors can have a handle or slot to enable easy safe transport of the capacitors from one location to another. Thermal capacitors containing salt that has been cooled are returned back to solar thermal capacitor system to recycle into heating process. This process will repeat as long as a solar power generation condition exists.
[0070] As shown in FIG. 13 , the thermal capacitor 16 are used as heating fuel cells to use in stoves 70 to cook food or to warm houses 80 . In a preferred embodiment, devices are contemplated that can conduct and/or transmit the heat for its intended use, e.g., cooking or heating. A stove, for example, can be used for both cooking and heating. Thermal capacitor cells with molten salt replace thermal capacitor cells with salt in its solid form. Utilizing invention thermal capacitor cells provide a renewable fuel cell that does not emit lethal gas. An insulator can be placed on the outside of thermal capacitor cell to avoid burning. Alternatively, or in parallel, thermal capacitor cells can be moved by tools that are developed specifically for the fuel cell or as simple as a stick.
[0071] In an alternate embodiment (not shown), solar thermal capacitor system can be tied into a heating system for houses. Thermal capacitors can be placed in long tubes under or in the structure of a house (permanently or by replacement) and heated with a solar concentration system.
[0072] In an preferred embodiment of the present invention, the molten salt thermal capacitors are also used as battery fuel cells. Accordingly, the invention further comprises an anode and cathode connection to enable charging. Molten salt batteries are a of class high temperature electric battery that use molten salts as an electrolyte. They offer both a higher energy density through the proper selection of reactant pairs as well as a higher power density by means of a high conductivity molten salt electrolyte. They are used in services where high energy density and high power density are required. These features make rechargeable molten salt batteries a promising technology for powering electric vehicles. High operating temperatures of 400° C. (752° F.) to 700° C. (1,292° F.) typically would bring problems of thermal management and safety, and place more stringent requirements on the rest of the battery components. In the present invention, when used in extreme environments or environments with limited resources, high operating temperatures are permissible.
[0073] While there are many different types currently being researched, the usual characteristics is to employ a mixture of various salt carbonates (e.g., Na2CO3, sodium carbonate & other carbonates of lithium, potassium, etc.) as the electrolyte of a battery called a fuel cell. High temperature rechargeable molten salt batteries have been known that use transition metal sulfide cathodes. LiAl alloy anode, and a molten lithium-salt electrolyte. Molten salt cells are a class of primary cell and secondary cell high temperature electric battery that use molten salts as an electrolyte. They offer both a higher energy density through the proper selection of reactant pairs as well as a higher power density by means of a high conductivity molten salt electrolyte. They are used in services where high energy density and high power density are required.
[0074] Sodium is attractive because of its high reduction potential of −2.71 volts, its low weight, its non-toxic nature, its relative abundance and ready availability and its low cost. In order to construct practical batteries, the sodium must be used in liquid form. Since the melting point of sodium is 98° C. (208° F.) this means that sodium based batteries must operate at high temperatures, typically in excess of 270° C. (518° F.). [citation needed]
[0075] Sodium-sulfur battery and lithium sulfur battery comprise two of the more advanced systems of the molten salt batteries. The NaS battery has reached a more advanced developmental stage than its lithium counterpart; it is more attractive since it employs cheap and abundant electrode materials. Thus the first commercial battery produced was the sodium-sulfur battery which used liquid sulfur for the positive electrode and a ceramic tube of beta-alumina solid electrolyte (BASE) for the electrolyte.
[0076] The ZEBRA battery operates at 250° C. (482° F.) and utilizes molten sodium aluminum chloride (NaAlCl4), which has a melting point of 157° C. (315° F.), as the electrolyte. The negative electrode is molten sodium. The positive electrode is nickel in the discharged state and nickel chloride in the charged state. Because nickel and nickel chloride are nearly insoluble in neutral and basic melts, intimate contact is allowed, providing little resistance to charge transfer. Since both NaAlCl4 and Na are liquid at the operating temperature, a sodium-conducting β-alumina ceramic is used to separate the liquid sodium from the molten NaAlCl4.
[0077] For comparison, LiFePO4 lithium iron phosphate batteries store 90-110 Wh/kg and the more common LiCoO2 lithium ion batteries store 150-200 Wh/kg. Nano Lithium-Titanate Batteries store energy and power of (116 Wh & 72 Wh/kg) and (1,250 W & 760 W/kg).
[0078] The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention. | The present invention relates to a zero-emission renewable heating system utilizing a thermal energy capacitor system using solar power as its source of heat, and more particularly, to a solar thermal capacitor system using an solar concentrators and a molten salt cell with thermal storage capability. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional application of U.S. Ser. No. 09/990,808 filed Nov. 20, 2001 for a Cotton Holding Disk.
FIELD OF THE INVENTION
[0002] The present invention relates to the field of pharmaceutical packaging, more particularly, to the aspect of inserting a packing filler such as cotton into a bottle containing tablets to prevent damage to the tablets during handling and shipping.
BACKGROUND OF THE INVENTION
[0003] In the past, it has been known to insert a filler such as cotton into bottles containing tablets or pills. It is to be understood that rayon may be used in place of cotton, and that the term “cotton” as used herein means actual cotton or a cotton substitute such as rayon. Automated machines have been developed and are in use to insert cotton into each bottle in the process of packaging pharmaceutical pills for retail sale. Cotton or cotton-like filler material has been found desirable because of its resiliency and deformability to act as internal packing in the bottle, to reduce or eliminate movement of the pills or tablets in the bottle during subsequent handling in manufacturing, distribution and sales. However such cotton inserting machines suffered from a deficiency in that the cotton, being somewhat resilient, would tend to partially eject itself from the bottle immediately upon retraction of the inserting implement, causing difficulty in the operation of the machine. When the cotton rebounds and extends above the neck of the bottle after withdrawal of the insertion pusher, the projecting cotton was observed to interfere with the operation of the cottoner machine by catching or snagging on the cotton fill tube, causing the bottle to become misoriented with respect to the machine. This problem is particularly exacerbated when relatively small diameter cotton is used with relatively large diameter mouth bottles. It has been found desirable to use such small diameter cotton with large mouthed bottles to reduce or avoid the need for multiple diameters of cotton for use with various sized bottles. In the present situation, using small diameter cotton having a cross section of between 1 and 2 inches for “20 gr” (20 grams/yard rayon) with wide mouthed bottles (having an opening of about 2{fraction (7/16)} inches diameter) has resulted in jam rates of between about 25 percent of the throughput. Such a jam rate is of course unacceptable.
[0004] It has been further observed that projecting cotton causes difficulty in subsequent closure of the bottle, typically by means of a cap carrying a safety seal therewithin, typically secured by induction heating and requiring an unobstructed contact between the safety seal and the top rim of the bottle.
[0005] When the cotton remained in the bottle, the closure would be able to be accomplished satisfactorily, with the cap threaded onto the bottle and the safety seal secured to the rim of the top of the bottle. However, cotton protruding substantially above the rim of the bottle top was found to interfere with the closure process, including securing the safety seal to the bottle top.
[0006] The present invention overcomes the shortcoming of the automated machines described above, by preventing substantial escape and protrusion of the cotton above the bottle top immediately after the cotton is inserted into the bottle. It is only necessary to temporarily contain the cotton in connection with the cottoner machine environment of the present invention since the machine typically has a second pusher downstream of the cotton inserter pusher to “repack” the cotton in the bottle neck prior to closure of the bottle at a further downstream station. With the present invention, jam rates have been observed to fall to something less than about one out of sixty bottles, or less than 0.0166 per cent, while still using relatively small cotton diameter in relatively large diameter opening bottles. Use of a single size cotton has the advantage of reducing the sizes of cotton needed for a range of bottles to be processed of about 2 inches to about 2¾ inches mouth diameter in the Cottoner machine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] [0007]FIG. 1 is a perspective front view of a prior art “Cottoner” machine suitable for inserting cotton into bottles showing the cotton holding disk improvement of the present invention.
[0008] [0008]FIG. 2 is an exploded rear view of the cotton insertion station portion of the Cottoner machine of FIG. 1.
[0009] [0009]FIG. 3 is a perspective view of the cotton holding disk mounted on the cotton installing cylinders of the cottoner machine, enlarged to show details thereof more clearly.
[0010] [0010]FIG. 4 is a partially sectioned fragmentary side elevation view (taken along line 4 - 4 of FIG. 3) of the cotton insertion station portion of the Cottoner machine shown with a plurality of bottles progressing past the station.
[0011] [0011]FIG. 5 is a section view of a representation of a bottle cap suitable for closing one of the bottles shown in FIG. 4.
DETAILED DESCRIPTION
[0012] Referring now to the figures and most particularly, to FIG. 1, a “Cottoner” machine 10 may be seen. This machine is available from the NJM/CLI Packaging Systems International company at 56 Etna Road, Lebanon, N.H. 03766-1403 (www.njmcli.com) as a Model CL-110 COTTONER. Also included in FIG. 1 is the improved apparatus of the present invention, a cotton holding disk 12 . Machine 10 has a conveyor 14 to transport a plurality of bottles 16 past the machine 10 to insert cotton therein as will be described in more detail infra. Machine 10 has a pair of inserter tubes 18 , 20 which reciprocate between two positions 180 degrees apart. The reciprocation enables filling one tube with cotton while the other tube discharges cotton into a subjacent bottle. It is to be understood that the cotton is “folded” approximately in half as it is received in each of tubes 18 or 20 , and will expand somewhat (in an inverted “V” orientation) once it is received in a bottle 16 . Once a cotton “V” is inserted into a bottle, the tubes reciprocate 180 degrees, where the empty tube is filled with cotton, and the other tube discharges cotton to another subjacent bottle. This process is repeated continuously moving the fill tubes 18 and 20 between a discharge position proximate the bottle where the cotton is inserted into the bottle and a loading position distal of the bottle where cotton is loaded into the tube, for as long as there are bottles to be loaded with cotton. It is to be understood that prior to advancing to the machine 10 , the bottles have been filled with tablets at another machine (not shown, but adjacent an upstream extension of the conveyor 14 ).
[0013] Referring now also to FIGS. 2 and 3, tubes 18 and 20 are carried by a yoke 22 which is attached via a hub 24 and bushing 26 to a rotary actuator 28 . Actuator 28 is supported on a baseplate 30 rigidly affixed to a frame (not shown) of the machine 10 . A shaft 32 of actuator 28 projects through an aperture 34 of baseplate 30 to reciprocate yoke 22 and tubes 18 and 20 on command. In FIG. 3, tube or cylinder 18 is located at a loading position where cotton is inserted into tube 18 , and tube or cylinder 20 is located at a discharge position where cotton previously loaded into tube 20 is discharged into a bottle, as may be seen more clearly in FIG. 4. The direction of reciprocation is indicated by arrow 35 .
[0014] Referring now again to FIG. 2, an air cylinder 36 is carried by a pusher support block 38 and is operable to move a tube pusher 40 in the form of a piston able to be received in either of tubes 18 or 20 . Pusher 40 is attached to and carried by a piston 44 of cylinder 36 . Block 38 is rigidly attached to baseplate 30 to allow pusher 40 to project through aperture 42 in baseplate 30 .
[0015] Referring now most particularly to FIG. 3, disk 12 has a generally planar plate 50 , preferably with a circular periphery, and a pair of attachment collars 52 . Each attachment collar 52 has a fixed portion 54 and a removable portion 56 . The fixed portion 54 may be integral with the plate 50 , or it may be secured thereto by any conventional means, such as threaded fasteners, preferably flat head machine screws. The removable portion 56 is preferably removably secured to the fixed portion 54 by a pair of threaded fasteners 58 such as machine screws. Collars 52 clamp disk 12 to the tubes 18 and 20 . More particularly, disk 12 is attached to tubes 18 and 20 by clamping the respective removable portion 56 against the fixed portion 54 of each collar 52 with a lowermost end of the respective tube 18 or 20 gripped between the fixed and movable portions of the collar which together form a clamp. Disk 12 has a pair of apertures 62 , 64 aligned with the tubes or cylinders 18 and 20 . Each of apertures 62 and 64 is surrounded by one of the collars 52 . It is to be understood to be within the scope of the present invention to attach disk 12 to cylinders 18 and 20 by any other conventional means.
[0016] Referring now most particularly to FIG. 4, tube 20 preferably projects through disk 12 such that the lowermost edge of tube 20 (and tube 18 ) is in the same plane as a generally planar lower surface 60 of disk 12 . Attachment with this alignment will avoid interference with the tops of bottles subjacent the tubes 18 , 20 . Alternatively, apertures 62 and 64 may have a stepped counterbore (not shown) with an upper diameter equal to the outside diameter of the tubes, and a lower diameter equal to the inside diameter of the tubes. Other aperture geometries are to be considered within the scope of the present invention, as well. For example, the lower or “exit” diameter of the aperture may have a chamfered or rounded cross section contour if the stepped counterbore is used, to reduce the chance of the cotton snagging on the exit diameter contour.
[0017] Once the cotton is inserted by pusher 40 , the bottle 16 moves from position 16 a to position 16 b and subsequently downstream of the disk 12 , where plunger 84 (visible in FIG. 1) repacks the cotton prior to bottle closure at a capping station (not shown) adjacent conveyor 14 and downstream of the machine 10 .
[0018] Referring now most particularly to FIG. 5, a cap 66 for the bottles 16 may be seen. It is to be understood that cap 66 is shown in somewhat of a schematic form. Cap 66 preferably carries a layer of pulpboard 68 , a layer of wax 70 , a layer of aluminum foil 72 and a layer of a polymer 74 in a cover 76 . It is to be understood that a laminate made up of layers 72 and 74 form a safety seal for the bottle. The aluminum layer 72 is induction heated at the capping station to melt the polymer layer to a top rim 78 of the bottle 16 , after cap 66 is placed on the bottle at the capping station. When the aluminum layer 72 is heated, the wax layer 70 melts and is drawn by capillary action into the pulpboard layer 68 , releasing the safety seal from the cover and layer 68 .
[0019] It will be apparent that any protruding cotton may interfere with the hermetic seal formed between the aluminum layer 72 and the rim 78 of the bottle 16 . It is thus important to assure the cotton remains within the bottle 16 and does not substantially protrude. Disk 12 accomplishes this by extending over the cotton filled bottle immediately downstream of the bottle immediately subjacent the tube then inserting cotton, as illustrated in FIG. 4. In FIG. 4, cotton 80 is about to be inserted from tube 20 by pusher 40 into bottle 16 a , while cotton 82 is retained in bottle 16 b by the lower surface 60 of disk 12 .
[0020] The material of plate 50 and collars 52 may be a polycarbonate or other polymer. The plate 50 of disk 12 is preferably ¼ inch thick, but may be made thicker or thinner, as desired. It has been found suitable to insert between 1 and 4 pieces of cotton into the bottles of tablets, as desired. The clearance or spacing 86 between the planar lower surface 60 and the mouth or top of the bottle 16 is preferably about one eighth inch.
[0021] It can thus be seen that moving or positioning the lower planar surface 60 of disk 12 superjacent (closely above) the bottle 16 prevents the cotton 82 from springing back out of the bottle at location 16 b after it is inserted by pusher 40 . By maintaining the cotton under the disk 12 , additional insertions of cotton have been found to be more readily retained in the bottle. Disk 12 also relieves machine 10 from jams that otherwise occur when cotton that is not set all the way into the bottle interferes with the tube 18 or 20 that is inserting it, when the tube is reciprocated to receive another load of cotton. It has been found that in the absence of disk 12 , protruding cotton is susceptible of being hit by reciprocating tubes ( 18 or 20 ) causing bottles to tip over, jam or shift along the conveyor 14 , interfering with the timing of the bottles on the conveyor, possibly causing conveyor jams. As has been mentioned above, after the bottle goes past the disk 12 , a further plunger 84 tamps the cotton into the bottle before capping. The disk 12 has been found to enhance the tamping action of the further plunger 84 . Bottles having a mouth opening of between about 2 inches diameter and about 2¾ inches diameter are believed suitable for use with the present invention. Most preferably, bottles having a mouth opening of about 2¼ to 2½ inches diameter are desirably used with the present invention. With bottles having an inside diameter opening of 2{fraction (7/16)} inches, the jam rate has been found to be something less than 0.0166 percent using the present invention with the smaller cotton or rayon.
[0022] This invention is not to be taken as limited to all of the details thereof as modifications and variations thereof may be made without departing from the spirit or scope of the invention. | Apparatus and method for retaining cotton in a bottle using a cottoner machine which inserts cotton via a pair of rotatable cylinders alignable with a mouth of the bottle, the apparatus including a disk secured to the cylinders via a pair of collars and having a pair of apertures aligned with the cylinders, and the method including a process of positioning a planar surface of the disk closely superjacent the mouth of the bottle after insertion of the cotton. | 1 |
BACKGROUND OF THE INVENTION
This invention generally involves a locking mechanism for suspending well flow controls in a landing sub in a tubing or casing string disposed in an oil well borehole.
The usual type of locking devices for suspending flow control devices, such as valves, in a landing sub utilizes expandable collet fingers having bevelled shoulders arranged to be expanded outward and locked into matching internal channels in the landing sub or landing nipple. The spring type collets are arranged to flex radially inward when passing through obstructions and when entering the landing sub. When it is desirable to lock the tool in the sub, a sleeve or wedge is driven up inside the spring collets to prevent their inward flexing and to fixedly secure the collet shoulders in the internal sub channel.
A disadvantage of the spring collet type of locks is that they tend to be difficult to set completely, and also that the bevelled shoulders may be pulled out of the locking channels even when set because of the angled sides of the bevel shoulders which do not provide a truly positive abutment in the sub channel.
The present invention provides a positive locking mechanism which utilizes a single, unitary, locking member to overcome the disadvantages of the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-3 are cross-sectional schematic illustrations of one embodiment of this invention in various stages of operation;
FIG. 4 is an isometric view of the rotatable locking member;
FIGS. 5 and 6 are directed to an alternate embodiment of the locking member.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-3, the locking mechanism 10 is shown located concentrically inside a landing sub assembly 11, which assembly has an upper threaded collar 12 and a lower threaded collar 13. The upper threaded collar 12, threadedly engaged on sub 11, is arranged to be threadedly engaged into the lower end of a section of well conduit; and collar 13, which is threadedly engaged at the bottom of sub 11, is arranged for threaded engagement with the upper end of a lower section of conduit 14. The landing sub 11 is characterized in having an inner angular locking channel 15 formed in the wall thereof.
The locking mechanism 10 has an upper mandrel 16 threadedly engaged in a lower mandrel 17. A tubular locking member 18 having a dual-axis bore passage therethrough is concentrically located about the lower mandrel 17. A retention collar 19 is located below member 18 in abutting relationship therewith. A mandrel sleeve 20 is located concentrically between lower mandrel 17 and locking member 18. Sleeve 20 is frangibly secured to mandrel 17 by means of shear screws 21 threadedly engaged in sleeve 20 and projecting inward with engagement with a circumferential channel 22 formed in the lower end of mandrel 17.
Retention collar 19 is threadedly engaged with mandrel sleeve 20 and abuts member 18 along its lower edge. A setting sleeve 23 is slidably located externally on the upper portion of mandrel sleeve 20 and has spring fingers 24 arranged for engagement in a circumferential channel 25 formed in the outer wall of mandrel sleeve 20. A locking sleeve 26 is slidably located on sleeve 23. A spring abutment collar 27 is slidably located about the upper and lower mandrels 16 and 17 and contains a plurality of radial openings 28 in which are located locking pins 29. A coil compression spring 30 is located atop collar 27 and is in abutment therewith and with an outwardly projecting flange 31 formed on mandrel 16.
Retention collar 19 is provided with a lower annular external flange 32 above which is located annular packing seals 33 held by seal retainer ring 34 which is threadedly engaged at the upper end of retention collar 19.
Setting sleeve 23 has at its lower end a plurality of the spring arms 24, each of which has a lower inwardly projecting shoulder area 35a and outwardly projecting shoulder area 35b. Shoulder 35a is adapted for close fitting relationship in channel 25. An upper sloping face 36 on shoulder 35a is adapted for slidable movement along a correspondingly angled sloping surface 37 of channel 25. Setting sleeve 23 further has a plurality of holes or openings 38 passing through the wall thereof through which are slidably located engagement pins 39. A circumferential channel 40 is formed in the external wall of mandrel sleeve 20 and is sized to allow snug engagement of pins 39 therein upon proper alignment of sleeve 23 with mandrel sleeve 20. Setting sleeve 23 is also provided with an annular external wedge shoulder 41 projecting outwardly therefrom. Locking sleeve 26 is provided with a lower inner annular shoulder 42 having a sloping face 43 which matches shoulder 41 of sleeve 23. Locking sleeve 26 is also provided with an inner annular wedge shoulder 44 projecting inward to abut pins 39.
A fishing tool attachment ring 45 is threadedly engaged in the upper end of locking sleeve 26 and a plurality of shear screws 46 are threadedly engaged and pass through the wall of sleeve 26 to project into an external channel 47 in mandrel sleeve 20.
Referring now to FIG. 4, a cross-sectional view of tubular member 18 is shown to better illustrate the particular features of this member. Tubular member 18 comprises a generally cylindrical tubular structure having two intersecting bore passages passing therethrough. The longitudinal central axes of the two bore passages are designated at X--X and Y--Y. The bore passage associated with axis X--X is defined by cylindrical inner walls 48 and 49. The bore passage associated with axis Y--Y is defined by cylindrical walls 50 and 51. The diameters of the bore passages X--X and Y--Y are larger than the diameter of mandrel sleeve 20. The tubular member is designed to have an arcuate pivot surface 52 along the bottom side thereof, lower abutment surfaces 53 and 56 along the lower right hand side of the member wall, and upper abutment surfaces 54 and 55 at the top of the left hand wall. Lower abutment surface 53 extends across the bottom of the tubular member and intersects arcuate surface 52 preferably near or between the X--X axis and the Y--Y axis.
When the tubular member is located about mandrel sleeve 20, such that the longitudinal axis X--X is substantially aligned with the longitudinal axis of sleeve 20, the locking member is in the relaxed, non-locking position. When the member is rotated, such that axis Y--Y becomes substantially parallel to the axis of sleeve 20, then abutment surfaces 54 and 56 have been rotated outwardly for engagement in the appropriate channel or opening in the wall of the tubing or the sub 11.
In typical operation, the locking mechanism 10 is lowered by means of wireline (not shown) to the desired location in the tubing string which the operator can determine from a wireline apparatus measuring system. A weighted member may be placed atop the locking mechanism to facilitate downward movement through the tubing string. The locking mechanism is arranged so that it may move downward through any number of obstructions similar to the landing sub 11 without engaging or activating the locking member. Setting of the locking mechanism in the desired location is achieved by bringing the mechanism back up through the desired landing sub and then lowering the mechanism 10 back into the sub whereupon engagement of the locking mechanism will occur in the sub setting channel 15.
In FIG. 1, the mechanism 10 is illustrated having passed through the landing sub 11. To accomplish such passes, locking pins 29 are located above the upper end of mandrel 17 and are flexed inward by the engagement of the outward bevelled shoulders of pins 29 with the inner wall of sub 11. The tool is placed in the tubing string in the condition illustrated in FIG. 1. As it moves downward in the string, the pins 29 will engage any inwardly projecting shoulders or obstructions, and will be pushed upward moving abutment collar 27 upward thereby compressing coil spring 30 against shoulder 31. Pins 29 will continue to move collar 27 upward until the pins are allowed to slide inward against mandrel 16, thereby allowing the mechanism to move downward through the shoulder or obstruction. The compressed coil spring 30 will continue to maintain a downward biasing force on collar 27 and pins 29 so that as soon as an annular open area, such as that formed by collar 13 below sub 11 is reached, the pins will be cammed up on enlarged end 57 of mandrel 17 into the annular opening.
At this point, the mechanism is ready to be engaged in locking relationship in sub 11. This is accomplished by pulling up once again on mandrel 16 and 17. At this point, pins 29 will abut the lower end of the sub 11 and prevent upper movement of collar 27 and sleeve 26. As a result, the inner mandrel 16 and 17 will move upward shearing pins 46 until the enlarged area 57 passes beneath pins 29 and they are consequently wedged inward to set in the reduced area of mandrel 17 below end 57.
FIG. 2 illustrates the mechanism as it is being lowered back through the landing sub 11. When seals 33 engage the lower restricted bore portion 58, this will set up friction between the seals and the seal bore 58 and continued downward movement of the locking mechanism 10 through the sub will result in a partial telescopic collapsing of the mechanism with the inner mandrels 16 and 17 moving downward through the seal retention collar 19 and mandrel sleeve 20. Simultaneously, the abutment of pins 29 within radial slots 28 and shoulders 57 on mandrel 17 will serve to move collar 27 downwards into abutment with sleeve 26.
The upper inner shoulder 44 of sleeve 26 abuts pins 39 passing through radial openings 38 in the wall of setting sleeve 23 which abutment serves to move sleeve 23 downward as sleeve 26 moves. The downward movement of sleeve 23 moves it into abutment with the top abutment surface 55 of member 18. Simultaneously, the friction force acting on seal retention collar 19 arising from the friction of seals 33 in seal bore 58 serves to move collar 19 upward relative to the tubular member 18. The upward movement of collar 19 results in abutment with the lower abutment surface 53 of the locking member. This simultaneous abutment from above on surface 55 and from below on surface 53 applies a rotational moment to the member 18 which tends to rotate it in a counterclockwise direction until it has contacted the inner wall of the sub 11 above channel 15. Upon obtaining this abutment with wall 18, as illustrated in FIG. 2, the seals 33 will resume movement into seal bore 58 until the moment the uppermost edge of the member 18 clears the top portion of locking channel 15. At this point, further rotation of locking member 18 resulting from the continuously applied rotational moment thereon serves to move the abutment faces 54 and 56 outward to engage the sloping walls of channel 15 as illustrated in FIG. 3.
At the moment the locking member rotates to its fully engaged locking position as shown in FIG. 3, spring fingers 24 of setting sleeve 23 will have moved down a sufficient distance to fully engage in retention channel 25. Also with this engagement, the pins 39 will have moved inward into groove 40 allowing further downward movement of locking sleeve 26 until shoulder 44 of locking sleeve 26 has passed over shoulder 43. At this point, the locking sleeve has moved into a position overlapping spring fingers 24 thereby pinning them into permanent engagement in channel 25, with the abutment of shoulder 44 with shoulder 43 serving to maintain the locking sleeve over the spring fingers. This locks member 18 in its radially outwardly expanded position as shown in FIG. 3. Member 18 will now prevent upward or downward movement of the locking mechanism in the sub by the abutment of face 55 with the upper sloped wall of channel 15 and by abutment of surface 56 with the lower sloping wall of channel 15. The location of a flow control device, such as a safety valve within a tubing string, may be easily accomplished by previously attaching the flow control device to the threaded section 59 at the bottom of collar 19.
After the flow control device has been positioned in the well, the setting assembly, comprising mandrels 16 and 17, coil spring 30, and collar 27, is removed by pulling up on the wireline attached to mandrel 16, shearing screws 21. After removal of these components from the tubing string, the flow control valve is ready for use.
When it is desired to remove the locking mechanism and the flow valve from the borehole, a fishing tool may then be lowered downward through fishing ring 45 and actuated to hook under ring 45 so that upward force may be applied through the fishing tool, which upward force moves locking collar 26 upward until spring arms 24 are free which movement upward engages locking collar on shoulders 43. Continued upward movement serves to disengage spring arms 24 by the wedging or camming action of the sloped shoulders of 35a with the sloped wall of channel 25 until the spring arms have moved away from abutment with member 18. Continued upward movement of the fishing tool results in upward force being applied to mandrel sleeve 20, which upward force is transferred through lower surface 53 into member 18. Since spring arms 24 no longer abut the top surface 55 of member 18, the member is urged to rotate in a clockwise direction by the action of sloping faces 54 and 56 against the upper and lower sloping portions of channel 15. The member will eventually disengage from channel 15, allowing the entire remainder of the mechanism along with the flow control device attached therebelow to be removed from the tubing.
It is preferable to arrange member 18 so that contact of its lower abutment surface 53 or arcuate surface 52 with the upper surface of sleeve 19 always occurs at a point substantially aligned with the center of rotation of member 18 about sleeve 20.
This arrangement is preferred so that the total amount of counterclockwise rotational moment generated in member 18 occurs as a result of contact at the upper surface 55. Thus, abutment of the lower surface of 18 merely serves to prevent downward movement of the member, and the locking action occurs only when setting sleeve 23 moves downward against surface 55.
Because of this relationship, disengagement of member 18 from channel 15 may be more easily accomplished, since the only forces acting on the member during disengagement are the upward force of sleeve 19, acting through the rotational center of member 18, and the rotational force of the upper sloped wall of channel 15 wedging against contact face 54. This upper wedging force serves to establish a rotational moment in the opposite direction, i.e. in a clockwise orientation, which opposite rotational moment serves to rotate member 18 back into its non-locking configuration associated with bore passage X--X, and disengagement of the lock from the sub is achieved.
Alternate Embodiment
FIG. 5 illustrates an alternate embodiment of the locking member 118 having upper engagement shoulder 119 and a lower engagement shoulder 120. The locking member 118 is shown in FIG. 5 in place in a dual channel locking sub 121, wherein lower shoulder 120 is engaged in a lower channel 122, an upper shoulder 119 is engaged in an upper channel 123. In FIG. 6 is illustrated how the locking member is capable of transversing end gaps in tubing connected by collars or in casing connected by collars.
Although certain preferred embodiments of the invention have been herein described in order to provide an understanding of the general principles of the invention, it will be appreciated that various changes and innovations can be affected in the described locking mechanism without departing from these principles. For example, other means could be utilized to lock the tubular member into engagement in the landing sub; such means could include hydraulic means or rotational means. The invention, therefore, is declared to cover all changes and modifications of the specific example of the invention herein disclosed for purposes of illustration, which do not constitute departures from the spirit and scope of the invention. | An unitary tubular locking member is rotatably mounted on a mandrel along with sleeve means for pivoting the locking member into abutting engagement inside a landing nipple in a tubing string. | 4 |
FIELD OF THE INVENTION
This invention relates in general to fencing and more particularly to a multi-link garden trim fence.
BACKGROUND OF THE INVENTION
Garden trim fencing has been used in the past for aesthetic reasons, to provide a decorative trim around a garden, walkway or the like. Fencing of this variety has also been used to prevent erosion of flower beds. Specifically, the fencing operates to prevent washing away of soil through rain or ordinary watering of the garden.
One such prior art fencing comprises a plurality of concrete casting blocks which are deposited in a channel which is dug at the edge of a garden or flower bed. One disadvantage of such prior art flower trim fences is that each is independent of the adjacent blocks, and the blocks are not held together. In addition, it is often difficult to place the concrete blocks so as to follow the contour of a garden or flower bed or to achieve a smooth and even line or curve. For example, it is extremely difficult to create an even circular trim using such prior art concrete block fencing.
SUMMARY OF THE INVENTION
According to the present invention, a multi-link garden trim fence is provided in which all components or blocks of the fence are held tightly together and in place. The trim fence of the present invention may be used to create lines or curves such as circles, as well as traditional right angle corners, etc.
In accordance with a general aspect of the present invention, there is provided a garden trim fence adapted for installation in a channel dug into the ground, said garden trim fence comprising a wire, an anchor block, a plurality of adjacent vertically arranged regular blocks, each of said regular blocks having a hole extending horizontally from one side to an opposite side thereof for passing said wire therethrough so as to support said blocks, said hole being adapted to lie below ground level when installed, and said anchor block including means for securing a distal end of said wire.
BRIEF INTRODUCTION TO THE DRAWINGS
FIG. 1 is a perspective view of the garden trim fence of the present invention in assembled form;
FIG. 2 is a perspective view of a portion of the garden trim fence of the present invention comprising a plurality of interconnected regular blocks intermediate a pair of anchor blocks;
FIG. 3 is a perspective view of a regular block in accordance with the preferred embodiment;
FIG. 4 is a perspective view of an anchor block according to the preferred embodiment;
FIG. 5 is a perspective view of a riser block according to the preferred embodiment;
FIG. 6 is a perspective view of a corner block according to the preferred embodiment;
FIG. 7 is a plan view of a plurality of regular blocks connected to an anchor block;
FIG. 8 is a plan view of a plurality of regular blocks connected to a corner block;
FIG. 9 is a plan view of an assembled garden trim fence configured to form a circle;
FIG. 10 is a plan view of an assembled garden trim fence showing curved and straight sections; and
FIG. 11 is a side view of a fence configured with riser blocks terminate at either end by a pair of anchor blocks.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning to FIG. 1, a garden trim fence 1 is shown according to the present invention, defining the perimeter of a garden. The garden trim fence ; includes straight section of fence, right-angle corners as well as curved or arcuate fence sections. In contrast with the known prior art, the garden trim fence 1 of the present invention may be configured to follow the contour of the garden or flower bed so as to achieve a smooth and even line or curve.
With reference to FIG. 2, a further configuration of the garden trim fence of the present invention is shown, including subterranean interconnection of the blocks via a wire 3. In particular, the embodiment of the fence shown in FIG. 2 comprises a plurality of regular blocks 5 terminated at each end via a pair of anchor blocks 7. The centre blocks 5 and anchor blocks 7 each contain a hole or cylindrical bore through which the wire 3 passes, as described in greater detail below. The ends 9 of the wire 3 protrude from the anchor blocks 7 and are bent back approximately 160° so as to hold the blocks 5 and 7 firmly in place. To install the fence, the channel dug at the edge of the garden or flower bed approximately 4" deep and 3" wide (10 cm deep and 8.5 cm wide). The assembled fence is aligned and placed upright into the channel and soil is back filled and tapped lightly into place. When installed, approximately 4" to 5" (10 cm to 12 cm) of the fence appears above the ground. Furthermore, when installed, the wire 3 which holds the blocks together is hidden from the front and back and extends out of the fence only at the anchor blocks 7 where the short end 9 of the wire (approximately 1" in length) projects. In any event, the wire is beneath ground level.
With reference to FIGS. 3 to 6, each of the regular block 5, anchor block 7, riser block 11 and corner block 13 are shown. The blocks 4, 7, 11 and 13 are preferably fabricated from pressure treated wood or cedar, each cut to a length of between 21.3 cm to 34.9 cm with approximately 5 cm radius (convex) top and 5 cm radius (concave) bottom. The regular block 5, anchor block 7 and riser block 11 are preferably cut from 2" × 4" pressure treated wood or 2" × 4" cedar (FIGS. 3-5). The corner block 13 is preferably cut from 4" × 4" pressure treated wood or 4" × 4" cedar (FIG. 6).
Each of the blocks 5, 7, 11 and 13 has one or more holes or cylindrical bores extending therethrough, for extending the plastic coated fence wire 3. Specifically, the regular block 5 (FIG. 3) has a hole 15 extending horizontally from one side to an opposite thereof. In addition to the hole 15, the anchor block 7 includes to additional holes 17 and 19 for securing the wire end 9 as shown in FIG. 2. The riser block 11 incorporates a cylindrical bore or hole 21 extending from one side thereof to the opposite side at an angle α of from 15° to 45° (FIG. 5). Finally, the corner block 13 incorporates a hole or cylindrical bore 23 which is disposed on a 45° diagonal when viewed from the top (FIG. 8). Each of the holes 15-23 are preferably of 3/16" (4.8 mm) diameter.
In order to assemble the various blocks into a fence, the fencing wire 3 is measured to the desired length of the fence and cut 6" (approximately 15 cm) longer than the desired measured length. The wire 3 used to secure the blocks together is preferably plastic coated fence wire of approximately 5/32" (4 mm) diameter. With reference to FIG. 7, the wire 3 is first fed through the hole 17 (or 19) of anchor block 7, and the end 9 thereof is bent back 160°. The wire 3 is then fed through the holes 15 of regular blocks 5, and any combination of riser blocks 11, corner blocks 13 via respective holes 21 and 23, to form the desired fence configuration, ending with another anchor block 7 in which the wire 3 is passed and the end 9 of which is bent back at 160°. Examples of various configurations of fence are shown in FIGS. 9-11. For the circular configuration of FIG. 9, a single anchor block is used to connect opposite ends 9 of the wire 3 which passes through a plurality of circularly arranged regular blocks 9.
FIG. 10 shows a fence constructed of two lengths of wire 3 extending through two sections of regular blocks 5, terminated at opposite ends via a pair of anchor blocks 7 and interconnected via an intermediate anchor block.
With reference to FIG. 11, by using riser blocks 11, the garden trim fence of the present invention can be assembled to fit sloping surfaces.
The regular block 5 anchor block 7, riser block 11 and corner block 13 of the present invention may be mass produced via a machine comprising an apparatus for planting and advancing either 2" × 4" or 4" × 4" pieces of wood through a series cutting and drilling stations. Specifically, a jigsaw-type blade may be used to cut the top and bottom curves of the blocks, and hydraulically or air operated drills may be used to create the holes 15, 17, 19, 21 and 23 oriented at various predetermined angles as required.
Other embodiments or variations of the invention are possible. For example, the blocks 5, 7, 11 and 13 may be fabricated from injection moulded plastic or other substance and suitably coloured. All such variations and modifications are believed to be within the sphere and scope of the invention as defined by the claims appended hereto. | A garden trim fence adapted for installation in a channel dug into the ground, the garden trim fence comprising a wire, an anchor block, a plurality of adjacent vertically arranged regular blocks, each of the regular blocks having a hole extending horizontally from one side to an opposite side thereof for passing the wire therethrough so as to support the blocks, the hole being adapted to lie below ground level when installed, and the anchor block including means for securing a distal end of the wire. | 4 |
CROSS REFERENCE TO RELATED PATENT APPLICATION
This patent application is a continuation of U.S. Ser. No. 08/070,023 filed May 28, 1993, now abandoned, which is a continuation-in-part of the John S. Letcher, Jr. U.S. patent application Ser. No. 07/810,960, abandoned, for SYSTEM OF RELATIONAL ENTITIES FOR OBJECT ORIENTED COMPUTER AIDED GEOMETRIC DESIGN filed Dec. 19, 1991.
FIELD OF THE INVENTION
The invention relates to a method of representing two- and three-dimensional geometric objects in a data structure. The method is particularly useful in the field of computer-aided design and numerical-control manufacturing of complex geometric objects made up of curves, surfaces, and solids.
BACKGROUND OF THE INVENTION
Geometric definition is an essential element in the design of practically any object to be manufactured. Until recently, geometric definition was performed primarily by drafting scale drawings of the object. In the last two decades, computer-aided geometric design (CAGD) has largely supplanted drafting. In CAGD, mathematical representations of an object's geometry are stored in computer memory and manipulated by the computer user. Sometimes the product of a CAGD design is scale drawings produced on a plotting device; in other cases a CAGD representation of the object is transmitted to numerical-control (NC) machinery for automated production of the object. The CAGD representation may also serve as a basis for analysis and evaluation of the design aside from visual aspects, e.g. finite-element stress analysis.
One well-known example of a CAGD program is AutoCAD (R), produced by AutoDesk, Inc. of Sausalito, Calif. Initially a two-dimensional environment simulating the drafting process on paper, AutoCAD now provides a three-dimensional environment in which many types of geometric entities including points, lines, curves, surfaces and solids can be defined, positioned, and edited to build up extremely precise definitions of highly complex objects. There are other CAGD programs which are much less general than AutoCAD, but are better adapted to specialized purposes; e.g. FAIRLINE (R) by AeroHydro, Inc., which is adapted to the special task of creating fair surfaces for ship hull design. CAGD programs for workstation and mainframe computers, for example IGDS (R) by Intergraph Corp., Huntsville, Ala., provide more flexible surface and solid modeling entities, such as nonuniform rational B-spline (NURBS) surfaces.
In a CAGD program, each object springs into existence at the time when it is created, either by execution of a user command, or as a result of reading data from a file. In most circumstances the new object is positioned, oriented or constructed in some deliberate relationship to one or more objects already in existence. For example, line B may be created in such a way that one of its endpoints is one end of a previously existing line A. However, the relationship which was clearly in the mind of the user at the time line B was created is not retained by the CAGD program; so if in some later revision of the geometry line A is displaced, then line B will stay where it is and no longer join line A. A conventional CAGD representation of geometry therefore consists of a large number of essentially independent simple objects, whose relationships are incidental to the manner and order in which they were created, but are not known to the program.
If design always proceeded in a forward direction, the loss of relationship information would not be a problem. One would start a project, add objects until the design is complete, and save the results. However, it is well known that engineering design is only rarely a simple forward process. It is far more commonly an iterative process: design is carried forward to some stage, then analyzed and evaluated; problems are identified; then the designer has to back up to some earlier stage and work forward again. It is typical that many iterative cycles are required, depending on the skills of the designer, the difficulty of the design specifications, and any optimization objectives that may be present. In each forward stage, the designer will have to repeat many operations he previously performed (updating), in order to restore relationships that were disrupted by the revision of other design elements. For example, he may have to move the end of line B so it once more joins line A; he may have to do this many times in the course of the design. CAGD systems typically provide extensive editing functions to facilitate these updates.
Revision of a previously existing design to meet new requirements is a common situation where similar problems are encountered. A change that alters an early stage of the design process requires at least one forward pass through all the subsequent design stages to restore disrupted relationships. Particularly if the relationships, and the sequence of design stages to achieve them, have been lost (and they are not normally retained in a way accessible to the user), the updating process can be very difficult, error-prone and time-consuming.
Some partial solutions to this problem are known. In some CAGD programs including AutoCAD, lines A and B can be created together as part of a "polyline" entity; then their connectivity will be automatically maintained if any of their endpoints, including their common point, are moved. Christensen (U.S. Pat. No. 4,663,616) has disclosed the concept of a "sticky" attribute which causes selected lines to remain connected to objects they are deliberately attached to. Draney (U.S. Pat. No. 4,829,446) has disclosed the concept of giving points in two dimensions serial numbers, and locating another point in two dimensions (a "Relative Point") by its relationship (x,y coordinate offsets) to a numbered point. Oosterholt (U.S. Pat. No. 4,868,766) has disclosed the concept of giving all geometric objects names, and locating each object in relationship to at most one other object, in a tree structure of dependency. Ota et al. (U.S. Pat. No. 5,003,498) have disclosed a CAGD system in which some objects have names, and are used by name in the construction of other more complex objects. Saxton (U.S. Pat. No. 4,912,657) discloses a system of "modular parametric design" in which design elements can be stored and conveniently recreated with different leading dimensions.
As mentioned above, many CAGD surface modeling systems support only a single type of surface, e.g. the FAIRLINE (R) surface, which is created from explicit cubic splines lofted through a set of B-spline "Master Curves". Although this surface can be molded into a wide variety of shapes useful in its own domain of ship hull design, there are many shapes it cannot make; e.g. it cannot form either an exact circular cross section or a completely round nose, both common features of submarine hulls. CAGD programs suited to mechanical design, such as AutoCAD, frequently support several simple surface types such as ruled surfaces and surfaces of revolution, but do not support more complex free-form surfaces such as B-spline parametric surfaces. Although it is widely appreciated that there would be large advantages in supporting a broader set of curve and surface types within a single CAGD environment, this has heretofore been possible only in workstation and mainframe CAGD systems, presumably because of the complexity of the programming required.
One known partial solution to this problem is to support only a single surface type, which has sufficient degrees of flexibility to encompass a useful set of simpler surfaces as special cases. Nonuniform rational B-spline (NURBS) surfaces have been proposed to fill this role, since by special choice of knots and coefficients the NURBS curve can accurately represent arcs of circles, ellipses, and other useful conic section curves. Disadvantages of this approach include the obscure relationship between the selection of knots and coefficients to achieve a desired curve; the large quantity of data required to define even a simple surface such as a circular cylinder; nonuniformity of resulting parameterizations; and the general unsuitability of NURBS surfaces for interactive design of surfaces having special requirements such as fairness or developability.
In CAGD surface modeling systems, intersections between surfaces often account for much of the complexity in both the program and the user interface. In a typical application, surface Y is constructed, then surface Z is constructed in such a way that it intersects surface Y. The next step is often to find the curve of intersection of Y and Z; then portions of Y and/or Z which extend beyond that curve may be discarded (trimmed). The problem of intersection of two surfaces is inherently difficult, for several reasons. The two surfaces may not intersect at all. Finding any single point of intersection requires solution of three simultaneous, usually nonlinear, equations. These equations will be ill-conditioned if the intersection is at a low angle. The intersection may be a single point, a simple arc, a closed curve, a self-intersecting curve, or multiple combinations of these elements. The surfaces might actually coincide over some finite area. Once a curve of intersection is found, it is often difficult to indicate correctly which portion of which surface is to be discarded. After trimming, a parametric surface patch may no longer be topologically quadrilateral, so it can no longer be conveniently parameterized.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide a CAGD environment which minimizes the effort required to revise and update geometric models, by capturing, storing and utilizing essential dependencies between the model's geometric objects. A second object of the invention is to provide a CAGD surface modeling environment in which a wide variety of curve and surface types are supported for convenience and flexibility. A third object of the invention is to provide a CAGD surface modeling environment in which the difficulties of intersecting and trimming surfaces are largely avoided by providing convenient ways to construct surfaces which contact and join one another accurately in the first place, with contacts and joins that are automatically maintained during updates of the model.
SUMMARY OF THE INVENTION
In this summary, a three-dimensional design space is contemplated, utilizing Cartesian coordinates (x, y, z) for the location of points. Some principles of the invention could also be advantageously applied in a design space of two dimensions, or of more than three dimensions, or with non-Cartesian coordinates. Definition: An entity is a type of geometric object defined within the system, and requiring a specific set of data for its actualization. Common CAGD entities are the point, the line, the arc, the Bezier patch. Definition: An object is an actualization of an entity; for example, a point located at (1., 2., 3.). Definition: A logical model is any valid collection of objects, i.e., a set of valid objects in which all dependencies are satisfied. Definition: An absolute model is a geometric representation computed from a logical model, in which all points are located by their absolute coordinates.
The first objective just mentioned (utilizing dependencies) is achieved by associating with each object in the model a unique name (or number), and defining and implementing a series of entity types whose actualizations depend on, by referencing the names (or numbers) of, other objects in the model. According to the invention, the dependency relationship between objects has the logical form of a directed graph (digraph). This data structure is known to the program, is available to be manipulated by the user, is stored along with specific numerical data to form the complete internal representation of the model, and is used to selectively update the model following alteration of any component object. Those qualitative properties of the model which are automatically maintained by utilizing the data structure of dependencies are referred to below as "durable" properties.
Each node of the dependency digraph represents an object; each directed edge indicates the dependency of one object on another. The dependency can take many forms. For example, a Relative Point depends on another point object for its location. A B-spline Curve depends on each of the point objects which are its vertices. A Lofted Surface depends on each of the curve objects through which it is lofted, and it also depends, in turn, on each point object used in the definition of those curves. Dependency can extend to many levels. An object can depend on many other objects, and can have many other objects dependent on it.
Some objects may be defined in an absolute sense, having no dependency on any others. For example, an Absolute Point is specified solely by its coordinates x, y, z.
It is useful to classify and define entities first in terms of their dimensionality, and second in terms of their primary dependencies: Points are zero-dimensional objects.
An Absolute Point depends on nothing.
A Relative Point depends on another point.
A Bead is a point constrained to lie on a curve.
A Magnet is a point constrained to lie on a surface.
A Ring is a point constrained to lie on a snake.
Curves are one-dimensional objects.
A Line depends on two points.
An Arc depends on three points.
A B-spline Curve depends on two or more points.
A C-spline Curve depends on two or more points.
Surfaces are two-dimensional objects.
A Translation Surface depends on two curves.
A Ruled Surface depends on two curves.
A Revolution Surface depends on one curve and two points.
A C-Lofted Surface depends on two or more curves.
A Blended Surface depends on three or more curves.
A B-spline Surface depends on an array of points.
Snakes are one-dimensional objects, parametric curves constrained to lie on a parametric surface. Any snake depends on its surface.
A Line Snake depends on two magnets or rings.
A Geodesic Snake depends on two magnets or rings.
An Arc Snake depends on three magnets or rings.
A B-Spline Snake depends on two or more magnets or rings.
A C-Spline Snake depends on two or more magnets or rings.
The above list of entities is intended to be illustrative, but not necessarily complete. Extension of this system of entities in a now obvious way to include parametric solids (three-dimensional objects with parameters u, v, w), and point, curve and surface entities located relative to a solid by use of the solid's parametric coordinate system, is specifically contemplated.
A different useful classification may be made in terms of the dependency role each entity class can fulfill: When a point called for, any point entity may be used. When a bead is called for, only a bead may be used. When a magnet is called for, a magnet or ring may be used. When a ring is called for, only a ring may be used. When a curve is called for, any point, curve or snake entity may be used. When a snake is called for, a snake, magnet or ring may be used. When a surface is called for, only a surface may be used.
Use is made of parametric coordinates as part of the data for some of these entities. For example, a curve may be parameterized with a parameter t which varies from 0 at one end to 1 at the other. An Absolute Bead can then be located by specifying the curve and a specific value for t. A surface may be parameterized with parameters u, v each of which varies independently from 0 to 1. An Absolute Magnet can then be located by specifying the surface and a specific pair of parameter values for u, v. A snake is a parametric curve in the two-dimensional u, v parameter space of its supporting surface.
One useful form of representation of a logical model is a text description having one record for each object. The object record includes the entity type, the object name, various object attributes such as color and visibility, and any variable data required to actualize the object, presented in a predefined order peculiar to the entity. For example, the following set of five records is the solution to the "line A-line B" problem discussed above, according to the invention: AbsPoint A1 14 1 1. 1. 3.; AbsPoint A2 14 1 2. 1. 3.; Line line -- A 13 1 A1 A2; AbsPoint B2 14 1 2. 3. 3.; Line line -- B 13 1 A2 B2;
This model contains 5 objects: 3 Absolute Points (named `A1`, `2`, `B2`) and 2 Lines (named `line -- A`, `line -- B`). The numbers 14 and 13 are color specifiers, and the 1's that follow them specify visibility. This data clearly records the intention that `line -- B` start where `line -- A` ends, viz. at point `A2`. The dependency of `line -- B` on point `A2` creates the durable connection.
The following record adds one more object to this example: AbsBead bead -- B 12 1 line -- B 0.7; This creates a visible point, of color 12, constrained to remain on `line -- B` at a parameter value of 0.7, i.e., 70% of the way from point `A2` to point `B2`. Following any change in `line -- A`, `bead -- B` will still lie on `line -- B`, in the same relative location. The dependency of `bead -- B` on `line -- B` creates the durable relationship.
For purposes of output or display, an absolute model will be computed from the logical model. For this example, the absolute model would consist of:
a point, color 14 at (1., 1., 3.)
a point, color 14, at (2., 1., 3.)
a line, color 13, from (1., 1., 3.) to (2., 1., 3.)
a point, color 14, at (2., 3., 3.)
a line, color 13, from (2., 1., 3.) to (2., 3., 3.)
a point, color 12, at (2., 2.4, 3.)
Now suppose that the example model is changed by moving point `A2` to a new position (2., 1., 4.). This is accomplished by changing one element in one record of the logical model: AbsPoint A2 14 1 2. 1.4.; Following this change, the updated absolute model would consist of:
a point, color 14 at (1., 1., 3.)
a point, color 14, at (2., 1., 4.)
a line, color 13, from (1., 1., 3.) to (2., 1., 4.)
a point, color 14, at (2., 3., 3.)
a line, color 13, from (2., 1., 4.) to (2., 1., 3.)
a point, color 12, at (2., 2.4, 3.3)
The connection of `line -- A` and `line -- B` has been automatically maintained; `bead -- B` is still located on `line -- B`, and in the same relative position, i.e at 70% of the length of `line -- B`. This brief example illustrates the automatic updating of the model that is made possible by utilization of the digraph data structure of dependencies.
The internal or external representation of the data structure may well be different from this text representation, but will nevertheless encode the dependency information in a manner that is logically equivalent to a digraph.
The second objective (supporting a variety of curve and surface types) is achieved by a special organization of the program instructions. According to the invention, all point objects may be accessed through a single routine "Point", whose input parameter is the name or index of a point object, and which returns the x, y, z coordinates of the object. Within "Point", a case statement branches to separate routines for evaluating each specific point entity. It is essential that "Point" be programmed in a recursire fashion, so that it can call itself, or be called by routines that have been called by it.
Similarly, all curve and snake objects may be accessed through a single routine "Curve" whose arguments are the name or index of a particular curve, and a list of t parameter values, and whose return parameters include a tabulation of x, y, z coordinates. Within "Curve", a case statement branches to separate routines for evaluating each specific curve entity. It is likewise essential that "Curve" be programmed in a recursive fashion, since the data for any curve may depend on another curve. To the program module that calls "Curve", all types of curves and snakes are interchangeable; you give it a t, it gives you back a point x, y, z. To support a new curve entity, it is only necessary to define the data required for that entity; add one case to the "Curve" routine; and add one routine that evaluates the new entity.
In like fashion, there can be a single recursive routine "Snake" whose arguments are the name or index of a particular snake object, and a list of t parameter values, and whose return parameters include a tabulation of u, v parameter value pairs. If snakes are treated as curves in the two-dimensional u, v parameter space of a surface, then addition of a new curve entity automatically adds a new snake entity of the same type. Maintaining this correspondence of curve and snake types is advantageous since the user then need not learn and remember separate properties for curves and snakes.
In like fashion, there can be a single recursive routine "Surface" whose arguments are the name or index of a particular surface object, and lists of u and v parameter values, and whose return parameters include a tabulation of x, y, z coordinates. To support N surface types, the programming effort is only proportional to N, rather than N squared.
The third objective (avoidance of surface-surface intersection and trimming) is achieved by utilizing the dependency relationships disclosed above, and providing certain generally useful snake and surface entities. Two distinct problems are addressed here: (1) forcing two surface objects Y and Z to accurately share a common edge, and (2) forcing one surface object Z to end accurately on another surface object Y, along a curve which is not necessarily an edge of Y.
According to the invention, durable common edges between surfaces may be achieved by using common data to define the adjoining edges. For example, if the two surfaces are blended surfaces, whose data includes boundary curves, all that is required is to use the same curve object for the corresponding edges of the two surfaces. Two lofted surfaces will accurately join in the loft direction if their corresponding Master Curves have common endpoints along the edges where they adjoin. The SubCurve entity, which creates a new curve identical to the portion of a specified existing curve between two specified beads, allows construction of common edges even where commonality does not extend along a complete edge of one or both surfaces.
According to the invention, a surface Z having an edge which accurately and durably lies on another surface Y can be achieved by defining a snake S on Y, then using S for an edge curve in the subsequent specification of Z. This arrangement also provides an alternative solution for common edges, when S is specified to be a Line Snake lying along part or all of one edge of Y.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic perspective view that shows a computer system having a central processing unit and disk memory, keyboard, mouse, and monitor, on which is displayed a 3-dimensional geometric model as a wireframe.
FIGS. 2 to 5 are graphical diagrams that illustrate point objects: FIG. 2, Absolute Point and Relative Point; FIG. 3, Absolute Bead and Relative Bead; FIG. 4, Absolute Magnet and Relative Magnet; FIG. 5, Absolute Ring and Relative Ring.
FIGS. 6 to 10 are graphical diagrams that illustrate curve objects: FIG. 6, Line and Arc curves; FIG. 7, B-Spline Curve; FIG. 8, C-Spline Curve; FIG. 9, Sub-curve; FIG. 10, Relative Curve.
FIGS. 11 to 18 are graphical diagrams that illustrate surface objects: FIG. 11, Ruled Surface; FIG. 12, Translation Surface; FIG. 13, Revolution Surface; FIG. 14, Blended Surface; FIG. 15, C-Lofted Surface; FIG. 16, B-spline Surface; FIG. 17, Sub-surface; FIG. 18, Relative Surface.
FIGS. 19 to 24 are graphical diagrams that illustrate snake objects: FIG. 19, Line Snake; FIG. 20, Arc Snake; FIG. 21, B-spline Snake; FIG. 22, C-spline Snake; FIG. 23, Sub-snake; FIG. 24, Relative Snake.
FIG. 25 is an example of the dependency digraph for a simple model.
FIG. 26 is a block diagram that illustrates an example organization of program modules which implements the present invention. FIG. 27 is a graphical diagram that shows an example application.
FIGS. 28-32 are flow chart diagrams that illustrate example sequences of process steps for creating and modifying a three dimensional geometric model according to the invention.
FIGS. 33 and 34 are flow chart diagrams that illustrate the organization of Point and Curve primary program modules and an example strategy for Point object and Curve object evaluations using a lookup table.
FIG. 35 is a graphical diagram of a parametric solid object.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
One preferred embodiment of the invention is a computer program operating on a suitable computer system such as an IBM-PC compatible or engineering workstation with a high-resolution color graphics display. The input device can be either a keyboard or a mouse. The graphics display is used primarily to display wireframe images of the model in perspective and/or orthogonal views. Controls are provided so the user can freely rotate, zoom or pan to select appropriate views. Alternative screen windows can show the u, v parameter space of a surface; outline-form listings of objects and their dependencies; and the text form of the logical model. FIG. 1 shows a computer system having a central processing unit and disk memory 11, keyboard 12, mouse 13, and monitor 14, on which is displayed a 3-dimensional object as a wireframe 15.
In the graphics display, a visible point object is displayed as a small circle. A visible line, curve, or snake object is represented as a polyline with a user-selectable number of subdivisions. A visible surface object is displayed as a mesh of parameter lines having a user-selectable number of subdivisions in each parameter direction. With more advanced graphic display hardware, surface objects may be rendered as solids with hidden lines and surfaces removed.
All objects have a color attribute; this can select one color from a palette of 16. All objects have a visibility attribute; this is a 16-bit integer in which the bits have different significance for different classes of entities, as follows:
points:
bit 1: point is visible
curves, snakes:
bit 1: polyline is visible
bit 2: polygon is visible
bit 3: tick-marks displayed at uniform parameter intervals
surfaces:
bit 1: parameter lines in u-direction are visible
bit 2: parameter lines in v-direction are visible
bit 4: boundary is visible
The following is a list of entities supported in the preferred embodiment:
Point Class
Absolute Point (AbsPoint): x, y, z
x, y, z are the absolute coordinates of the point.
Relative Point (RelPoint): point, dx, dy, dz
dx, dy, dz are the coordinate offsets from `point`FIG. 2 shows an Absolute Point 21 and a Relative Point 22 located in a Cartesian coordinate system.
Absolute Bead (AbsBead): curve, t
t is an absolute parameter value on `curve`
Relative Bead (RelBead): bead, dt
dt is the parameter offset from `bead`FIG. 3 shows a curve 31 in 3-space mapped from a 1-D parameter space 32, an Absolute Bead 33, and a Relative Bead located in both spaces.
Absolute Magnet (AbsMagnet): surface, u, v
u, v are the absolute parameters on `surface`
Relative Magnet (RelMagnet): magnet, u, v
du, dv are the parameter offsets from `magnet`FIG. 4 shows a surface 41 in 3-space mapped from a 2-D parameter space 42, an Absolute Magnet 43, and a Relative Magnet 44 located in both spaces.
Absolute Ring (AbsRing): snake, t
t is an absolute parameter value on `snake`
Relative Ring (RelRing): ring, dt
dt is a parameter offset from `ring`FIG. 5 shows a snake 51 in 3-space mapped from a 1-D parameter space 52 through a 2-D parameter space 53, and an Absolute Ring 54 and a Relative Ring 55 located in all three spaces.
Curve Class
(All curves are parameterized from 0. to 1.)
Line (Line): pointl, point2
The Line is a straight line from `point1` (x 1 ) to `point2` (x 2 ):
x(t)=(1-t) x.sub.1 +t x.sub.2
Arc (Arc): point1, point2, point3
The Arc is a circular arc interpolating the three points in sequence. FIG. 6 illustrates Line 61 and Arc 62 objects, dependent on 2 and 3 point objects 63 respectively.
D-spline curve (BCurve): type, point1, point2, . . . pointN
type gives the B-spline order: 1=linear, 2=quadratic, etc.
The named points are the vertices in sequence. ##EQU1## FIG. 7 illustrates a B-Spline Curve object 71, dependent on a multiplicity of point objects 72; and its 1-D parameter space 73.
C-spline curve (CCurve): point1, point2, . . . pointN
The named points are interpolated in sequence.
The curve is a parametric cubic spline with chord-length parameterization, knots at the data points, and not-a-knot end conditions. FIG. 8 illustrates a C-Spline Curve object 81, dependent on a multiplicity of point objects 82; and its 1-D parameter space 83.
Sub-curve (SubCurve): curve, bead1, bead2
The sub-curve y(t) is the portion of curve x(s) from `bead1` (parameter s 1 ) to `bead2` (parameter s2):
y(t)=x[(1-t) s.sub.1 +t s.sub.2 ]
FIG. 9 illustrates a Sub-curve object 91, which is a portion of curve object 92 between two bead objects 93, 94; and the 1-D parameter spaces 95, 96 of the curve and the subcurve respectively.
Relative curve (CRelCurve): curve, point1, point2 The relative curve x(t) is formed from curve y(t) and the two points x 1 , x 2 by the linear transformation:
x(t)=y(t)+(1-t) [x.sub.1 -y(0)]+t [x.sub.2 -y(1)]
FIG. 10 illustrates a Relative Curve object 101, dependent on a curve object 102 and two point objects 103, 104; and its 1-D parameter space 105.
Surface Class
(All surfaces are parameterized from 0 to 1 in both u and v directions)
Ruled surface (RuledSurf): curve1, curve2 The surface is formed from the two curves y(t), z(t) by linear interpolation:
x(u,v)=(1-v) y(u)+v z(u)
FIG. 11 illustrates a Ruled Surface object 111, dependent on two curve objects 112, 113; and its 2-D parameter space 114.
Translation surface (TranSurf): curve1, curve2
The surface is formed from the two curves y(t), z(t) by addition:
x(u,v)=y(u)+z(v)-z(0)
FIG. 12 illustrates a Translation Surface object 121, dependent on two curve objects 122, 123, and its 2-D parameter space 124.
Revolution surface (RevSurf): curve, point1, point2, angle1, angle2
The surface point at u, v is constructed by taking a point y(v) from `curve`, then rotating it through an angle θ=(1-u) θ 1 +u θ 2 about the axis line from `point1` to `point2`. FIG. 13 illustrates a Revolution Surface object 131, dependent on one curve object 132 and two point objects 133, 134 which define an axis 135; and its 2-D parameter space 136.
Blended surface (BlendSurf): curve1, curve2, curve3, curve4
The surface is a bilinear Coons patch constructed from the four curves. If the four curves are oriented end-to-end as in FIG. 14, the equation for locating a surface point is: ##EQU2## FIG. 14 illustrates a Blended Surface object 141, dependent on four curve objects 142, 143, 144, 145; and its 2-D parameter space 146.
C-lofted surface (CLoftSurf): curve1, curve2, . . . curveN
A surface point x(u,v) is obtained in three stages: (1) from each curve i take the point x i (u); (2) form the C-spline curve which interpolates the x i (u) in sequence; (3) evaluate the C-spline at parameter v.
FIG. 15 illustrates a C-Lofted Surface object 151, consisting of an infinitude of C-splines 152 interpolating several curve objects 153.
B-spline tensor-product surface (BSurf): typeU, typeV, N, M, pointll, point12, . . . pointNM
typeU, typeV give the B-spline orders for u and v directions. N, M are numbers of vertices in u, v directions. point11, point12, . . . pointNM are a rectangular net of control points. ##EQU3##
FIG. 16 illustrates a B-spline Surface object 161, dependent on an array of point objects 162; and its 2-D parameter space 163.
Sub-surface (SubSurf): surface, snake1, snake2, snake3, snake4
The sub-surface is a portion of surface Y(P,q) bounded by the four snakes w1, w2, w3, w4 in end-to-end sequence. ##EQU4##
FIG. 17 illustrates a Sub-surface object 171, dependent on a surface object 172, four snake objects 173, 174, 175, 176; and the 2-D parameter spaces 177, 178 of the surface and the sub-surface respectively.
Relative surface (RelSurf): surface, point1, point2, point3, point4
The relative surface x(u,v) is formed from surface y(u,v) and the four corner points x 1 , x 2 , x 3 , x 4 by the bilinear transformation: ##EQU5##
FIG. 18 illustrates a Relative Surface object 181, dependent on a surface object 182 and four point objects 183, 184, 185, 186; and its 2-D parameter space 187.
Snake class
(All snakes are parameterized from 0 to 1. A snake is evaluated by first locating a point w={u,v} in the parameter space of the surface, then evaluating the surface with those parameter values.)
Line snake (LineSnake): magnet1, magnet2
The LineSnake is a straight line in u, v parameter space from `magnet1` (w1={u1, v1}) to `magnet2` (w2={u2, v2}):
w(t)=(1-t) w1+t w2
FIG. 19 illustrates a Line Snake object 191, dependent on a surface object 192 and two magnet objects 193, 194; and the 1-D parameter space 195 of the snake; and the 2-D parameter space 196 of the surface.
Arc snake (ArcSnake): magnet1, magnet2, magnet3
The ArcSnake is a circular arc in u, v parameter space interpolating the three magnets. FIG. 20 illustrates an Arc Snake object 201, dependent on a surface object 202 and three magnet objects 203, 204, 205; and the 1-D parameter space 206 of the snake; and the 2-D parameter space 207 of the surface.
B-spline snake (BSnake): type, magnet1, magnet2, . . . magnetN
type gives the B-spline order: 1=linear, 2=quadratic, etc. The named magnets are the vertices in sequence. ##EQU6##
FIG. 21 illustrates a B-spline Snake object 211, dependent on a surface object 212 and multiple magnet objects 213; and the 1-D parameter space 214 of the snake; and the 2-D parameter space 215 of the surface.
C-spline snake (CSnake): magnet1, magnet2, . . . magnetN
The named magnets are interpolated in sequence.
The snake is a parametric cubic spline in the u, v parameter space with chord-length parameterization, knots at the data points, and not-a-knot end conditions.
FIG. 22 illustrates a C-spline Snake object 221, dependent on a surface object 222 and multiple magnet objects 223; and the 1-D parameter space 224 of the snake; and the 2-D parameter space 225 of the surface.
Sub-snake (SubSnake): snake, ring1, ring2
The sub-snake w(t) is the portion of `snake` p(s) from `ring1` (parameter s 1 ) to `ring2` (parameter s 2 ):
w(t)=p[(1-t) s.sub.1 +t s.sub.2 ]
FIG. 23 illustrates a Sub-snake object 231, dependent on a surface object 232, a snake object 233, and two ring objects 234, 235; and the 1-D parameter spaces 236, 237 of the snake and sub-snake respectively; and the 2-D parameter space 238 of the surface.
Relative snake (RelSnake): snake, magnet1, magnet2
The relative snake w(t) is formed from `snake` p(t) and the two magnets m 1 , m 2 by the linear transformation:
w(t)=p(t)+(1-t) [m.sub.1 -p(0)]+t [m.sub.2 -p(1)]
FIG. 24 illustrates a Relative Snake object 241, dependent on a surface object 242, a snake object 243, and two magnet objects 244, 245; and the 1-D parameter space 246 of the relative snake; and the 2-D parameter space 247 of the surface.
TABLE III is a summary of the data items required to actualize each of the entities into an object.
Further entities which may be added to those described in detail above include the following:
Infinite (non-parametric) Planes specified in several ways, e.g. at specified x, y, or z coordinates; through three point objects; normal to a curve at a specified bead; tangent to a surface at a specified magnet;
Contour objects formed by intersection of surfaces with families of non-parametric planes, cylinders or spheres;
Mirrored Points, Curves, and Surfaces formed by reflecting any object of the specified class through a Plane, Line or Point object;
Projected Points, Curves, and Surfaces formed by projection of any object of the specified class onto a Plane or Line object;
Rotated Points, Curves and Surfaces formed by rotation of any object of the specified class about an axis Line object through a specified angle;
Foil Curves, Snakes and Foil-Lofted Surfaces utilizing standard airfoil curves;
Helix, conic, Catenary and Spiral curves;
NURBS Curves, Snakes and Surfaces;
PolyCurves, made by joining two or more specified curve objects end-to-end and reparameterizing from 0 to 1;
PolySnakes, made by joining two or more specified snake objects end-to-end and reparameterizing from 0 to 1;
Developable Surfaces, specified by two edge curves;
Fillet Surface, specified by two or more snakes on two different surfaces;
Swept Surfaces, formed by sweeping a parametrically varied cross-section curve along a specified curve object;
Projected Snake, formed by projecting a specified curve object onto a specified surface object;
Contour Bead, a Point object located at the intersection of a specified Curve object with a specified Plane object;
Contour Ring, a Point object located at the intersection of a specified Snake object with a specified Plane object;
Contour Snake, a Snake object located at the intersection of a specified Surface object with a specified Plane object;
BeadMagnet, a Point object at the intersection of a specified Curve object with a specified Surface object, and. serving as a bead on the curve and as a magnet on the surface;
RingMagnet, a Point object at the intersection of a specified Snake object with a specified Surface object, and serving as a ring on the snake and as a magnet on the surface;
BiSnake, a one-dimensional object located at the intersection of two specified Surface objects, and serving as a snake on either surface;
BiRing, a Point object located at the intersection of two specified Snake objects, and serving as a ring on either snake;
Parametric Solids such as Ruled Solid, Translation Solid, Revolution Solid, Blended Solid, B-spline Solid, C-lofted Solid, and NURBS Solid. FIG. 35 illustrates a Revolution Solid 300 formed by revolving a specified Surface object 302 through a specified angle θ, about a specified axis Line Y.
Logical models are stored as files in disk memory, in a text format similar to that previously outlined, but with some additional numerical parameters specifying polyline subdivisions for display. Each object is represented by a single text record beginning with the entity keyword indicated in parentheses in each of the above entity definitions. The keyword is followed by the object name, and color and visibility indices. Any curve or snake object will then have an integer telling the number of subdivisions desired for the polyline representing it in the display; any surface object will have two integers specifying the number of subdivisions in the u and v directions for the polyline mesh representing it in the display. Beyond this point, the required data for most entities is different, as indicated in the entity definitions above. The text file is terminated by the keyword "End". Remarks can be included in the text file by use of the keyword "Rem".
Internal to the program, objects are referenced by serial numbers corresponding to their sequence in the input data file, or sequence of creation. Requiring that all references be to previously defined objects is a simple way to eliminate the possibility of circular dependencies (digraph cycles). The organization of internal storage of the logical model includes a linked-list data structure representing the dependency digraph, to be used during updates of the absolute model. FIG. 25 is a digraph representing the dependencies in the "line A-line B" example developed in a previous section. The nodes 251 represent objects, and the edges 252 represent their dependencies.
The program has user-controlled capabilities for reading and writing logical-model data files in the appropriate text format, and for detecting and reporting errors and inconsistencies in a data file during read operations. The program can also read and display, simultaneous with displaying a model, one or more files representing 3-dimensional wireframes. The program can also write a 3-dimensional wireframe file of the absolute model currently displayed, or a 2-dimensional wireframe file of the current view.
Interactive capabilities are provided for creating, editing and deleting objects. Limited capabilities are provided for appropriate transmutations of objects to a different entity type; for example, any point object can be transmuted into an absolute point. In all these activities the program performs consistency checks and enforces rules ensuring the integrity of the digraph data structure. For example: all required dependencies have to be fulfilled before a newly created object is accepted into the logical model; an object cannot be deleted until all of its dependents have been deleted; circular dependencies are not permitted.
FIG. 26 shows an example organization of program modules which implements the invention. Each box 263, 264 represents a subroutine; each arrow 262 represents a subroutine call, with the arrow directed from the calling module to the called module.
The three special modules ("primary modules", 263) labeled "Point", "Curve" and "Surface" are the interface to any application program requiring absolute geometric information from the model. These have input and output arguments as follows:
Point--in: name (or index) of a point object
out: absolute coordinates x, y, z
Curve--in: name (or index) of a curve object list of t parameter values
out: list of point coordinates x, y, z
Surface--in: name (or index) of a surface object list of u parameter values list of v parameter values (or, list of u, v parameter pairs)
out: array of point coordinates x, y, z
(An input list of parameter values may have only a single entry, if only one point needs to be evaluated.)
The other modules ("secondary modules", 264) illustrated are not intended to be called from an application, being called only by the primary modules, as indicated by arrows, or in some cases by other secondary modules. These have input and output arguments as follows:
Bead--in: name (or index) of a bead object
out: identity of supporting curve t parameter value
Magnet--in: name (or index) of a magnet or ring object
out: identity of supporting surface u, v parameter pair
Ring--in: name (or index) of a ring object
out: identity of supporting snake t parameter value
Snake--in: name (or index) of a snake object list of t parameter values
out: identity of supporting surface list of u, v parameter pairs
The remaining secondary modules have the same arguments as the primary modules that call them.
Module "Point" determines what kind of point object it is evaluating and branches to the appropriate secondary routine, as indicated. Depending on the entity, "Point" may have to then call "Curve", "Snake", and/or "Surface" to complete its job. For example, if the object is any type of bead, "Point" calls "Bead", which returns the identity of the curve to which the bead belongs, and a single t parameter value. "Point" must then call "Curve" with this curve and parameter value, receiving back the x, y, z coordinates of the particular point occupied by the bead. Similarly, "Magnet" returns the identity of the surface which supports the magnet, and a u, v parameter pair. "Point" must then call "Surface" with this information, receiving back x, y, z coordinates. In the case of a ring, "Point" first calls "Ring", identifying the supporting snake and receiving a t parameter value; then it calls "Snake" with t and receives back identity of the surface and a u, v parameter pair; then it calls "Surface" with u, v and receives back x, y, z coordinates.
"Magnet" can be called with any object that can serve as a magnet, i.e. with a magnet or ring. If the object is a ring, "Magnet" first calls "Ring" to identify the snake, and a t parameter value; then calls "Snake" to identify the supporting surface and receive a u, v parameter pair.
"Curve", "Snake" and "Surface" are primarily branches to their constituent secondary routines. Since any point object can serve as a curve, "Curve" needs to be able to call "Point". Similarly, since any magnet or ring can serve as a snake, "Snake" needs to be able to call "Magnet". Also, since any snake object can serve as a curve, "Curve" must accept the index or name of a snake, call "Snake" to identify the supporting surface and receive back a list of u, v parameter pairs; then call "Surface" to evaluate x, y, z coordinates.
"Line" and "Line Snake" routines share a common "Line math" routine; similarly, the other curves and snakes share common math routines. The math routines are able to operate with either 2-D data (when called by a snake routine) or 3-D data (when called by a curve routine). It is obvious in FIG. 26 how easily a new parametric curve, snake, or surface entity can be added to the system; it requires only the addition of one secondary module implementing the new entity, and a small modification of one primary module, adding a branch to the new secondary module.
Some recursive calls are apparent as cycles in FIG. 26. The most obvious of these are the way "Magnet", "Bead" and "Ring" call themselves when they are evaluating a Relative Magnet, Bead or Ring. For another example, to locate a Relative Point, the program first needs to locate the basis point, no matter what kind of point object the basis point is. Thus, "Relative Point" must be able to call "Point". Similarly, "SubCurve" and "Relative Curve" must be able to call "Curve"; "SubSnake" and "Relative Snake" must be able to call "Snake"; and "SubSurface" and "Relative Surface" must be able to call "Surface".
Other potentially recursive calls to the primary routines are needed, which are not indicated by arrows in FIG. 26, because the arrows showing all such possibilities would be too numerous. For example, "Line", "Arc", "B-Curve" and "C-Curve" all need to evaluate their supporting points, by a series of calls to "Point". "Line Snake", "Arc Snake", "B-Snake" and "C-Snake" need to evaluate the u, v parameters of each of their supporting magnet objects, by a series of calls to "Magnet". The several surface routines need to evaluate various point, curve or snake objects, according to their individual constitutions; these are all done through calls to the primary modules.
Further levels of recursion occur when, for example, one curve supporting the surface being evaluated is a snake on another surface. In this case the sequence of calls passes through "Surface" twice. It is easy to think up cases with arbitrarily long chains of dependency. All such recursire possibilities are accommodated by the program structure indicated in FIG. 26. Without recursion, the program complexity and size would grow extremely rapidly with the allowable depth of dependency; with recursion, only stack space is required to indefinitely extend the permitted depth of dependency.
EXAMPLE APPLICATION OF THE PREFERRED EMBODIMENT
Table 1 is a text representation of an example logical model utilizing a variety of point, curve and snake objects, and six interconnected surface objects of various types, as defined and outlined above. FIG. 27 is a wireframe representation of the resulting absolute model. The example comprises hull, deck and cabin surfaces for a 30-foot sailing yacht design.
The example model has six surface objects: `hull` 271 and `deck` 272 are C-lofted surfaces; `cabin -- fwd` 273, `cabin -- side` 274, and `cabin -- aft` 275 are ruled surfaces; and `cabin -- top` 276 is a blended surface. The surfaces all have visibility 2, which causes only the parameter lines in the v-direction to be displayed. Eleven transverse sections 277 through the model are also displayed for purposes of visualizing the shapes.
`hull` is a C-lofted surface with three B-spline master curves `MCA`, `MCB`, `MCC`, each having four absolute points as vertices. `deck` also has three master curves; the first is the single point `MCAV1`, the other two are 3-vertex B-spline curves `deck -- beam` and `transom`. The join 278 between `hull` and `deck` is accurate and durable because the C-splines at the adjoining edges on each surface use the same data points, viz `MCAV1`, `MCBV1`, `MCCV1`, and therefore are identical curves.
The three ruled surfaces `cabin -- fwd`, `cabin -- side`, `cabin -- aft` are constructed in a similar fashion to one another; each uses a snake on `deck` as one edge, providing an accurate and durable join 279 to the `deck` surface, and a relative curve dependent on that snake as the second (upper) edge. The three snakes on `deck` join each other accurately and durably because they share common endpoint data, viz. magnets `dm3` and `dm5`. The three relative curves `top -- fwd`, `top -- side`, `top -- aft` also join each other accurately and durably because they are constructed using common end points, viz. relative points `rp3` and `rp5`. `cabin -- side` joins the other two surfaces accurately because its end rulings are the lines `dm3`-`rp3` and `dm5`-`rp5`, which are identical to end rulings on the adjoining surfaces.
The blended surface `cabin -- top` joins the three ruled surfaces accurately because it uses their upper edge curves `top -- fwd`, `top -- side`, `top -- aft` as data. Its fourth side is a three-vertex C-spline `top -- ctr`, which lies accurately in the centerplane because each of its vertices has a zero y coordinate.
The example model as now defined can easily be transformed into an extremely wide variety of alternative shapes by changing the coordinates of absolute points, the offsets of relative points, and the parameters of magnets. An example modification which affects all six surfaces is to increase the y coordinate of `MCBV1`. Following any such change, the connectivity and relative positioning of the several surfaces is automatically preserved as the absolute model is updated.
FIGS. 28-32 illustrate possible sequences of process steps for creating and modifying a three-dimensional geometric model in accordance with the invention. In these flowcharts, solid arrows represent the temporal sequence of execution, while dashed arrows represent the flow of data between program modules and computer memory. The memory elements, depicted as cylinders, can be any form of computer memory including but not limited to disk files and random-access memory (RAM).
FIG. 28 shows a possible sequence of steps for creating a model. The "Create object" step is elaborated in FIG. 29. An object is created by first selecting an entity, then filling in the data fields required to actualize that particular entity. All entities require an object name, color, and visibility. Curves and snakes require specification of t-divisions; surfaces require specification of u- and v-divisions. Each object requires further data, its quantity, character and sequence depending on the entity definition. To obtain the specification for this variable object data, the program accesses stored data coding the entity definitions. The data entered during the "Create object" step may come from user interaction, or may be read in from a data file.
In FIG. 28, following the "Create object" step, the resulting logical object data is stored in memory. In the next step, a wireframe representation of the object is made and stored in memory. During this "Make object wireframe" step, calls will be made to Point, Curve, or Surface routines as required by the class of entity. Next, the object wireframe is displayed; this will require a projection transformation if the display device is two-dimensional, as is usual.
While further objects need to be created, the program loops back to the "Create object" step. When the model is complete, both logical and absolute model data may be accessed to create output files, or for other evaluation purposes.
FIG. 30 illustrates a possible sequence of process steps for modifying a model in accordance with the invention. Editing can take place following completion of the steps of FIG. 28, or editing and creation steps may be interspersed. The first step in editing a model is to edit the logical data of a particular selected object. In this process the existing logical data for the object may be offered as defaults. The editing process is controlled by reference to the stored data which codes entity definitions and specifies what kind of data the entity requires. When the appropriate fields of object data have been altered, the logical object data representing this object in memory is updated. Making use of the stored dependency digraph, an "update list" is compiled of all objects affected by the change, i.e., first-generation dependents of the altered object, their dependents, etc. This list is headed by the altered object, is purged of duplicates, and is ordered so as to assure that all affected objects are updated in appropriate sequence, i.e. supports before dependents in every case.
The program next cycles automatically through the update list, creating an updated wireframe for each affected object. The "Update object wireframe" step during editing is essentially the same as the "Make object wireframe" step in FIG. 28, except that wireframe data of other objects may have to be moved if the new object wireframe is of different size from the existing one. When all affected objects have been processed, the entire model is up-to-date, and may be displayed, evaluated, and further modified.
LOOKUP TABLE DATA STRUCTURES AND PROCEDURES AS AN ALTERNATIVE TO DIRECT RECURSIVE EVALUATION
Lookup tables may be advantageously employed to improve the response of the program during initial evaluation and subsequent modification of a model. A portion of computer memory or disk memory (the "lookup table") is organized suitably for the storage of absolute object data. As each object is evaluated in sequence, its absolute coordinates and/or parameter values are recorded in the table. When and if this object is referenced during evaluation of later objects, the tabulated values can be used (usually by means of interpolation), rather than following the recursive evaluation procedure.
The lookup table is envisaged as being organized into "records", each record consisting of a variable number of real numbers, depending on the entity. A lookup table record will always contain x, y, and z values. For a bead, the record can additionally include t; for a magnet or snake, each record can include u and v; for a ring, each record can include t, u, and v.
A point object requires only a single record. A curve or snake object requires a sequence of records representing points distributed along the object. A surface object requires a sequence of records representing points distributed over the object in some orderly specified fashion.
For point objects, which require only one record and no interpolation, there is no loss of accuracy in using the lookup table.
For curve, snake, and surface objects, some loss of accuracy usually will result from the substitution of lookup table interpolation in place of direct recursive evaluation. This error depends in a complicated way on the number and distribution of the tabulated data points; the curvatures and higher derivatives of the tabulated object; the method of interpolation; and the specific parameter values for which the tabulated object needs to be evaluated. Because the interpolation error is difficult to predict or to bound, and because it accumulates from object to object as evaluation proceeds, the accuracy of the resulting absolute model is uncertain. However, it is known that even with the simplest interpolation scheme (linear interpolation for curves and snakes, bilinear interpolation for surfaces) and relatively coarse tabulations (such as 16 to 32 uniform divisions) the resulting accuracy is usually entirely adequate for visual evaluation and interactive editing. When greater accuracy is required, for example for N/C machining data, more accurate interpolation schemes can be employed; tabulated objects can be more finely subdivided; or direct recursive evaluation can be invoked.
The tabulated data need not be limited to points on the tabulated object. In a spline- or NURBS-based program, the tabulated data could be control points. If an interpolation scheme requiring derivative information is to be employed, the tabulated data would include first or higher derivative data.
Using lookup table interpolation, program structure can be substantially the same as FIG. 26, with one significant modification of each of the four primary modules. Each primary module will begin by accessing the index information in the table data and ascertaining whether the current object has been tabulated, and whether its tabulated data is up-to-date. If the table index data indicates that an up-to-date tabulation exists, the primary routine will branch to an appropriate interpolation routine (or, in the case of Point, will simply read the tabulated data); otherwise, it will follow the usual recursive path. In the second case it is apparent that the recursion will never be more than one level deep, since all supporting objects will have already been tabulated.
FIGS. 33 and 34 illustrate the organization of Point and Curve primary modules, respectively, for object evaluations using the lookup table. In all cases, if the object is found to be tabulated, then the usual recursive calls are avoided. The Curve primary module contains a loop which cycles through the evaluation of all requested points before exiting. Snake and Surface primary modules may be organized similar to Curve, except that surfaces require bidirectional interpolation.
FIGS. 31 and 32 illustrate possible sequences of steps for utilizing lookup tables during model creation and editing respectively. The essential differences from FIGS. 28 and 30 are the presence of the lookup table data structures, and the addition of a "Make object tabulation" or "Update object tabulation" step which stores data in these structures, using calls to primary modules to generate table data. Not apparent in these flowcharts is the advantage that the primary modules can use interpolation rather than regenerating object data recursively. The "Make object wireframe" and "Update object wireframe" steps utilize data from the lookup table. The "Extract geometric data" step also can access data from the lookup table when appropriate.
Parametric solids are disclosed in the Summary of the Invention above and an example is illustrated in FIG. 35. In this example, a Revolution Solid 300 is formed by moving a specified Surface object 302 through a specified angle θ about the axis Line Y.
TABLE II is a program listing of a program entitled RGS.BAS, written in the computer language QuickBasic 4.5, which implements the disclosed method of computer aided design of geometric models, including automatic updating of the entire model following a change in a supporting geometric object. RGS.BAS is organized in accordance with the block diagram of FIG. 26. Each block in the diagram is implemented as a separate QuickBasic subroutine. Each arrow in the diagram of FIG. 26 is identifiable as a CALL Statement in the program. To illustrate a useful application of the primary routines, RGS.BAS includes routines that compute a 3-dimensional wireframe such as the ones illustrated in FIGS. 2-25 and 27. The routines that compute the wireframe call the primary routines Point, Curve, and Surface in order to receive all required geometric information about the absolute model.
RGS.BAS reads lines from an ASCII text file containing the description of an arbitrary logical model as disclosed and defined in this patent specification. The example set forth in TABLE 1 of this specification is a valid input file. Each geometric object is specified with a geometric object record of one or more lines in the input file, terminated by a semicolon. The order of data in a geometric object record is: entity keyword; object name; color; visibility; and variable entity data. Data items in a geometric object record are separated by one or more spaces. Variable length lists of supporting geometric object names are enclosed in braces{}. Remarks are permitted using the keyword "Rem". The input file is terminated by the keyword "End".
RGS.BAS reads the input file and stores an internal representation of the logical model in arrays, including a representation of the directed graph data structure of multiple dependencies. It computes from this stored internal representation a 3-dimensional wireframe representation of the implied absolute model, using recursion as required to support multiple levels of dependency. RGS supports by computer implemented steps all 28 of the geometric entities disclosed in this patent specification.
RGS.BAS outputs 3-dimensional wireframe data to an ASCII text file in a prescribed format (3DA). The output file can easily be translated to a variety of CAD formats including 3-dimensional DXF files for AutoCAD. It can be directly displayed in 3 dimensions with off-the-shelf software such as AeroHydro's C3D.
RGS.BAS provides user interaction allowing the user to alter any of the numerical values in any point object. Using the stored digraph data structure, RGS.BAS selectively updates all geometric objects affected by the change, and writes a new wireframe file for the updated absolute model.
TABLE 1______________________________________Text representation of logical model for the exampleapplication.(Entity keyword; name; color; visibility; variable entitydata)Rem 3×4 cloft hull with deck and cabin for patent exampleAbsPoint MCAV1 14 1 0.00 0.00 3.60;AbsPoint MCAV2 14 1 1.00 0.00 1.41;AbsPoint MCAV3 14 1 2.50 0.00 -0.84;AbsPoint MCAV4 14 1 3.00 0.00 -0.90;BCurve MCA 12 1 20 2 { MCAV1 MCAV2 MCAV3 MCAV4 };AbsPoint MCBV1 14 1 15.00 5.84 2.64;AbsPoint MCBV2 14 1 15.00 6.00 0.54;AbsPoint MCBV3 14 1 15.00 3.90 -1.20;AbsPoint MCBV4 14 1 15.00 0.00 -1.44;BCurve MCB 12 1 20 2 { MCBV1 MCBV2 MCBV3 MCBV4 };AbsPoint MCCV1 14 1 30.00 3.50 2.76;AbsPoint MCCV2 14 1 30.90 3.50 1.41;AbsPoint MCCV3 14 1 31.70 2.50 0.22;AbsPoint MCCV4 14 1 31.70 0.00 0.22;BCurve MCC 12 1 20 2 { MCCV1 MCCV2 MCCV3 MCCV4 };CLoftSurf hull 10 2 20 30 0 1 MCA MCB MCCAbsPoint transom0 14 1 29.80 0.00 3.00;AbsPoint transom1 14 1 29.80 1.75 3.00;BCurve transom 10 1 10 2 { MCCV1 transom1 transom0 };AbsPoint deck.sub.-- ctr 14 1 15.00 0.00 3.45;AbsPoint deck.sub.-- mid 14 1 15.00 2.70 3.45;BCurve deck.sub.-- beam 10 1 10 2 { MCBVL deck.sub.-- mid deck.sub.-- ctr };CLoftSurf deck 7 2 8 10 { MCAV1 deck.sub.-- beam transom };AbsMagnet dm1 11 1 deck 1.00 0.27;AbsMagnet dm2 11 1 deck 0.63 0.27;AbsMagnet dm3 11 1 deck 0.35 0.30;AbsMagnet dm4 11 1 deck 0.20 0.50;AbsMagnet dm5 11 1 deck 0.20 0.70;AbsMagnet dm6 11 1 deck 1.00 0.70;BSnake footprint.sub.-- fwd 11 1 10 2 { dm1 dm2 dm3 };BSnake footprint.sub.-- side 11 1 20 2 { dm3 dm4 dm5 };LineSnake footprint.sub.-- aft 11 1 10 dm5 dm6;RelPoint rp1 11 1 dm1 2.00 0.00 1.30;RelPoint rp3 11 1 dm3 2.00 0.00 1.10;RelPoint rp5 11 1 dm5 -0.20 -0.50 1.40;RelPoint rp6 11 1 dm6 -0.30 0.00 1.80;RelPoint rp7 11 1 deck.sub.-- ctr 0.00 0.00 1.65;RelCurve top.sub.-- fwd 11 1 10 footprint.sub.-- fwd rp1 rp3;RelCurve top.sub.-- side 11 1 20 footprint.sub.-- side rp3 rp5;RelCurve top.sub.-- aft 11 1 10 footprint.sub.-- aft rp5 rp6;RuledSurf cabin.sub.-- fwd 11 2 10 1 footprint.sub.-- fwd top.sub.-- fwd ;RuledSurf cabin.sub.-- side 11 2 20 1 footprint.sub.-- side top.sub.-- side ;RuledSurf cabin.sub.-- aft 11 2 10 1 footprint.sub.-- aft top.sub.-- aft ;CCurve top.sub.-- ctr 11 1 10 2 { rp1 rp7 rp6 };BlendSurf cabin.sub.-- top 14 2 4 5 { top.sub.-- fwd top.sub.-- side top.sub.-- aft top.sub.-- ctr };______________________________________End ##SPC1##
TABLE III__________________________________________________________________________Summary of entity definitions.Entity Name Color Visibility t-divisions u, v-divisions Variable data__________________________________________________________________________AbsPoint x x x x, y, zRelPoint x x x dx, dy, dzAbsBead x x x curve, tRelBead x x x bead, dtAbsMagnet x x x surface, u, vRelMagnet x x x magnet, du, dvAbsRing x x x snake, tRelRing x x x ring, dtLine x x x x point1, point2Arc x x x x point1, point2, pointsBCurve x x x x type, { point }CCurve x x x x { point }SubCurve x x x x curve*, bead1, bead2RelCurve x x x x curve, point1, point2LineSnake x x x x magnet1, magnet2ArcSnake x x x x magnet1, magnet2, magnet3BSnake x x x x type, { magnet }CSnake x x x x { magnet }SubSnake x x x x snake*, fing1, ring2RelSnake x x x x snake, magnet1, magnet2RuledSurf x x x x curve1, curve2TranSurf x x x x curve1, curve2RevSurf x x x x curve, point1, point2, angle1, angle2BlendSurf x x x x curve1, curve2, curve3, curve4CLoftSurf x x x x { curve }BSurf x x x x typeu, typev, N, M, { point }SubSurf x x x x surface*, snake1, snake2, snake3, snake4RelSurf x x x x surface, point1, point2, point3,__________________________________________________________________________ point4 Key: x data item is required *data item is redundant and could be omitted { . . . }variablelength list of objects of specified class | A method of computer aided design of geometric models including the steps of: defining a set of geometric entities for use in constructing the geometric models, each of the geometric entities being an abstract geometric object type that is adapted to be actualized into one or more geometric objects, the geometric entities including point class entities, curve class entities, and surface class entities; identifying some of the geometric objects by corresponding unique object identifiers; defining a plurality of relational entities along the set of geometric entities, each of which is adapted to be actualized into corresponding relational objects having having a dependency relationship upon one or more other geometric objects whose object identifiers are specified within the relational objects; wherein the relational entities include a curve class entity having a dependency relationship on a point class object; wherein at least one of the relational entities is a surface class entity having a dependency relationship on a point class object or a curve class object; and defining a set of subroutines for evaluating the plurality of geometric objects, there being a corresponding subroutine for each of the abstract geometric object types, wherein those subroutines which evaluate relational objects are programmed to make calls to an appropriate one or more subroutines to evaluate the geometric objects on which that relational object depends. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention is related to the control of sessions at self-service terminals. More particularly, the present invention is related to a control of the processing/closing of sessions at self-service terminals based on the face of the users.
[0003] 2. Description of the Prior Art
[0004] Biometrics is a technique used in a wide range of distinct systems. The technique is based on the capture of information relative to an individual that might be able to differentiate such individual from others. Such information is generally obtained from the individual's fingerprints, voice or facial features. Irrespective of the source, however, the use of biometrics is always associated to the recognition of an individual, either in the context of identifying a person from among a known group, or to check whether the identity being alleged by an individual is actually certifiable. Documents Nos. U.S. Pat. Nos. 6,853,739 and 6,724,919, for example, describe user verification systems based on biometric data.
[0005] Both tasks, of verification and identification, are based on the same premise: i) a representative model of each user must be previously generated during a registration phase; and ii) when the system is in use, the biometric data having been obtained is compared with the stored models, thereby generating a probabilistic value that is used to clear the access of that user or to identify the same from among the models having been generated.
[0006] Self-service terminals, particularly automatic teller machines used in banking transactions, due to constituting constant targets for fraud, represent a field of application for biometric systems. For those terminals, the option of use of facial features as a data source constitutes a natural choice, since it is the only one that is constantly providing data without unduly bothering the user. In all such terminals, however, the use of facial feature information is associated to the verification of the user, that is, the authorization for use of the terminal if the biometric data having been obtained, upon being compared with the model related to the alleged identity, provides results that confirm that the user is indeed the individual that he or she alleges to be. The document “ Face Recognition/Detection by Probabilistic Decision-Based Neural Network ” of Lin, Lin and Kung, published in 1997 in IEEE Transactions on Neural Networks , for example, describes how a whole face-based automatic recognition system can be implemented with the use of probabilistic neural networks.
[0007] In this context, there is not known to exist, in the prior art, any application that makes use of biometric data for controlling a session initiated at a self-service terminal.
OBJECTIVES OF THE INVENTION
[0008] One of the objectives of the present invention is to provide a method and a self-service terminal that are capable of automatically terminating a session initiated by a user, based on the monitoring of the user's face.
[0009] One other objective of the present invention is the provision of a method and a self-service terminal that requires, in a less repetitive manner during the same session, the confirmation of user identification data, also based on the monitoring of the face of the user that initiated the session.
[0010] One other objective of the present invention is to provide a method and a self-service terminal capable of sending alerts to a control center and/or to the user that initiated a session at the self-service terminal in the case that more than one face is identified within the field of sight of the camera.
[0011] Those objectives and other advantages of the present invention will be further evident from the description to follow and from the drawings attached hereto.
BRIEF DESCRIPTION OF THE INVENTION
[0012] The self-service terminal session control method according to the present invention starts from the beginning of a session initiated by a user. After that point, an image capture device is activated, and starts capturing image frames. Such frames are processed in order to identify at least one face. If a face is identified, a model is temporarily associated to that face. The said face is monitored until the session is terminated by the user, generating the possible events: i) in the case that the user leaves the terminal while the session is in course, or in the case that a new face assumes the position of the previous face, the result of the comparison with the temporary model shall bring about the terminating of the session; and ii) if the same user stays until concluding the session, the result of the comparison with the temporary model will allow the reduction or elimination of user data confirmation requests. The method may further comprise an alert generation step, for the case where more than one face is detected in one or more frames. Such alert may be displayed to the user himself/herself (indicating the presence of an intruder in the region of the terminal) or may be sent to an external control center.
[0013] The self-service terminal according to the present invention will comprise a processor capable of executing all the steps of the method described above, a memory means for storing the temporary models, and an image capture device.
DESCRIPTION OF THE FIGURES
[0014] The detailed description provided below refers to the attached figures, wherein:
[0015] FIG. 1 there is illustrated an exemplary conventional bank self-service terminal or automatic teller machine;
[0016] FIG. 2 there is depicted a flow diagram of the generation of events for control of the session in a self-service terminal in accordance with a preferred embodiment of the present invention; and
[0017] FIG. 3 there is shown a block diagram representing the self-service terminal of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0018] In FIG. 1 there is shown a self-service terminal 10 commonly known in the art. In addition to all the elements required to provide the terminal with functionalities, such as a card reader, a keypad, a deposit collection slot, etc., the self-service terminal 10 should comprise an image capture device 11 duly positioned to capture images of the area located in front of the terminal 10 and of the face of its users.
[0019] FIG. 2 illustrates the steps of the present invention. A user, upon initiating E 1 a session at the terminal 10 , normally by inputting a password and/or inserting a card, will enable the operation of the image capture device which will start to capture E 2 several frames of its field of sight. Thereupon, the captured frames are processed in the terminal 10 in order to allow the identification of at least one face E 3 . Optionally, if more than one face is identified in the same image frame, an alert is generated E 6 and such alert is displayed to the very user at the terminal or is sent to an external control center. Such identification may indicate the presence of an unauthorized person attempting to visualize some information of the user that initiated the session. The system described in U.S. Pat. No. 5,995,847 shows the manner in which remote alerts can be sent to a remote control center, from events occurring locally at self-service terminals. The description of that document is incorporated herein as a reference.
[0020] Alternatively, the image capture device 11 may capture frames irrespective of the beginning of a session. In such case, the processing of the captured frames would be started with the start of the session. Optionally, each captured frame in which a face has been identified may be reduced by the removal of regions located outside of the face of interest.
[0021] Subsequently, a given frame containing a face is processed for the extraction of that face and the creation of a temporary model E 4 , if no model has already been created in the same session. Optionally, such model is a simple histogram and there is attributed thereto an identification number. In the course of the session at the self-service terminal, new frames continue to be captured and processed for the extraction of faces, which are compared with the temporary model having been created E 5 . The comparison of an extracted face with the model provides similarity values that may be set against a previously established threshold value. If the result of the comparison exceeds the threshold, the face is considered to be the same. If the result of the comparison falls below the threshold, the face is deemed to belong to a different user than that of the model. The capture of new frames for the extraction of faces to be compared with the model, or alternatively, the identification of faces in a captured frame, may be performed, for example, on a frame-by-frame basis, at every ten frames or at other rates depending on the intended application.
[0022] By means of the procedure outlined above, whenever that during a session initiated by a user, there is detected a change of face, that is, a change of user, the session may be automatically terminated. Furthermore, the course of a session can be streamlined since that, in case no face change is identified, the obtainment of identification data, for example by means of the information of passwords or the insertion of personal cards, can be dispensed with at each step within the same session. Preferably, for enhanced robustness, the change of faces is established only upon the identification of a number of comparisons that result in values below the threshold. In the same manner, the determination of the presence of two or more faces in the terminal area is established only upon the identification of those faces in a certain number of image frames. It should be understood that the two events described above, e.g., the closing of the session and the streamlining of the course of the session, may be present either individually or simultaneously in the method and the self-service terminal according to the present invention.
[0023] The self-service terminal according to the present invention is essentially based on the elements that already constitute the self-service terminals of the prior art. As may be seen in FIG. 3 , the self-service terminal 10 comprises a processor unit 20 connected to a memory device 22 wherein is stored a program comprising instructions that reflect the steps mentioned above. One other memory device 23 is also connected to the processor unit 20 for storing the temporary models. The temporary models may be kept stored for only one session. Alternatively, the models may be stored for a few days, if it is desired to monitor the use of the terminals, such as in the case of frauds, for example. In that case it will be necessary to attribute a unique identification value to each model. In U.S. Pat. No. 6,520,410 it is described how the internal software of a self-service terminal might be developed/modified for the insertion of new functionalities. The content of that document is also incorporated hereby for purposes of reference.
Signal Processing: Capture of the Image Signal and Search for a Face
[0024] The obtainment of image signals by a camera and the search for a face in those signals is already commonly knowledge in the art. Among the various applicable technologies, one may cite that which is described in document No. WO 2008/018887, the contents of which are hereby incorporated for purposes of reference. The system described in that document is capable of performing the identification and tracking, in real time, of more than one face in an image signal stream, by sub-sampling of the digital signal acquired by the camera and by calculating the integral image for a portion of at least one candidate region.
[0025] One other adequate and readily applicable technology is the open library OpenCV (http://sourceforge.net/projects/opencvlibrary) (http://opencv.willowgarage.com), initially developed by Intel Corporation and containing functions in computer language for the processing of images in real time. Its content may also be understood by means of the publication “ OpenCV: Computer Vision with the OpenCV Library ”, which content is also incorporated herein for purposes of reference. Additional programs, based on that same library, were developed for face detection and tracking, such as, for example, the program developed by Zeeshan Ejaz Bhati (www.codeproject.com/KB/library/eyes.aspx).
Acquisition of a Face, Generation of a Model and Result of the Comparison
[0026] The same document No. WO 2008/018887 shows how a face can be identified and its region extracted from a captured frame.
[0027] The OpenCV library allows the creation of a histogram, accessible as a normal matrix, from any image supplied thereto. In the present case, such image will be the extracted face. One other functionality of the OpenCV library is the direct comparison of images. In such situation, the face extracted after the beginning of the session will serve as a model, e.g., as a reference face. The faces obtained from the subsequent frames will be the template images that will be compared with the reference image. Various forms of comparison are possible, among which there may be cited the following: the simple squared difference between the images (0 indicating a perfect identity and higher values indicating greater differences); the correlation that multiplies the template by the reference image (high values corresponding to good similarity and low values corresponding to large differences); and the use of correlation coefficients comparing the reference image average to the template average (1 indicating perfect correlation, 0 indicating no correlation, and −1 indicating de-correlation). The values obtained by those comparisons are set against a previously established threshold for the acceptance or rejection of a face as being identical to that of the reference model.
[0028] Notwithstanding that the above described techniques are used in a particular embodiment of the present invention, other techniques, including more complex ones such as the probabilistic neural networks, may be used for the creation of the temporary models. | A method for controlling a session of a self-service terminal utilizes an image capture device that captures image frames for identification of a user's face. If a face is identified, a model is temporarily associated with that face. The face is monitored until the user closes the session, thereby generating possible events. When the user leaves the terminal during the session, or a new face assumes the position formerly held by the previous face, the result of the comparison results in the closing of the session. In the case that the same user remains in place until the end of the session, the result of the comparison allows the reduction of requests for confirmation of user identification data. | 6 |
FIELD OF THE INVENTION
The present invention relates to reading aids for individuals with upper extremity disabilities, arthritis, or other conditions that require hands-free reading and more particularly to devices, systems and methods for turning the pages of reading material such as books.
BACKGROUND AND PRIOR ART
It is well-known to use an eraser tip of a pencil or hand-held erasers or rubber thimble type finger covers for turning pages of reading material, counting money and otherwise handling papers to be moved individually. However, this does not solve the problem of holding a book or volume when the person is disabled or needs to have his or her hands-free when referencing manuals, technical literature and the like.
In reference circular No. 93-02 entitled, Assistive Devices for Reading published online (http:www.makoa.org/gov/assistiv.htm) by the National Library Service for the Blind and Physically Handicapped, Library of Congress, Washington, D.C. 20542 (September 1993), pages 1-5 provide a comprehensive list of Book Holders and Book Stands, and on pages 27-28, a list of commercially available “Page Turners” is provided. Among the page turning devices disclosed in Assistive Devices for Reading there is a range from complex, such as, those operated with a pneumatic switch, pedal controls, joysticks to very simple devices, including tapered strips with foam-rubber tips and rubber friction tips on a wooden dowel.
A number of prior art inventions have been made which provide means for holding, supporting and/or turning the pages of reading material, such as books, but such prior art devices are usually costly and complicated. Several prior art inventions are described briefly in the following summaries.
U.S. Pat. No. 4,467,991 to Bailes discloses an armchair reading stand having a pair of rails coextensive with and slidably connected to the undersurface of the book support panel in tongue and groove fashion.
U.S. Pat. No. 4,644,675 to Berger et al. illustrates a page turning device having a support for the book and power driven rotating disc which turns the pages.
U.S. Pat. No. 4,685,374 to Goldner illustrates a page turning device having a rotatable elongated arm that uses a circular motion to turn pages.
U.S. Pat. No. 4,882,969 to Ricca illustrates a page turning device whereby after a book is secured, a plurality of rotatable rods are activated to turn a page by using a foot-operated pedal.
U.S. Pat. No. 5,149,046 to Kerley et al. describes a page turning system having a pair of rectangular frames connected to one another by a hinge to vary the inclination of the reading materials and a pair of bent spring mounted wires for holding opposing pages of the reading material open for reading and a variable friction adjustment to enable the force of the wires against the pages to be varied while permitting manipulation of pages by a stick employed by the reader.
U.S. Pat. No. 5,634,623 to Hoijtink describes a device for holding a publication such as a book or magazine between two L-shaped supports with a brush-like surface that are slidable relative to each other and adapted to accommodate a publication between them.
U.S. Pat. No. 5,979,857 to Holm describes an adjustable book holder which can be attached to a stand to permit hands-free reading and hand assisted page turning in a sitting or reclining position; pages are held open with a monofilament line.
U.S. Pat. No. 6,234,441 B1 to Gordon describes a bookstand with a base adapted to fit under a person's leg and a pivotal arm connected to the base to hold the book support or platform; a page retainer extends across the opposing opened pages.
U.S. Publication No. 2001/0010351 to Schutze illustrates a book holding device having an adjustable support plate.
U.S. Publication No. 2001/0023916 to Armstrong illustrates another book display apparatus having a transparent front section made from Plexiglas.
None of the prior art references provides an inexpensive, easy to operate, multiple use book holder and door-operated page turning device combination that holds a page open with no obstruction of view and accommodates a wide variety of reading materials, including but not limited to, hard-covered books, paperbacks, magazines, catalogs, bound papers, sheet music and the like. The present invention provides such a device.
SUMMARY OF THE INVENTION
It is a primary objective of the present invention to provide door-operated page turner devices, systems and methods for holding a book and its pages in a steady position for hands-free reading.
A second objective of the present invention is to provide door-operated page turner devices, systems and methods for the disabled and for those who must refer to the reading material preferably without touching it with their hands, such as cooks, mechanics, and musicians.
A third objective of the present invention is to provide door-operated page turner devices, systems and methods for printed materials which is similar to and as simple as an eraser-tipped pencil.
A fourth objective of the present invention is to provide door-operated page turner devices, systems and methods that can be easily fabricated in a variety of sizes to accommodate hard-covered books, paperbacks, magazines, catalogs, bound papers, sheet music and the like.
A fifth objective of the present invention is to provide low-cost page turner devices, systems and methods that does not create a fire or safety hazard by avoiding electrical, electronic, pneumatic, hydraulic, or mechanical rotating or reciprocating components, making it safe to be used even in bed where the reader may fall asleep.
A sixth objective of the present invention is to provide door-operated page turner devices, systems and methods on a basic platform or case that accommodates a large variety of reading material ranging from standard size and oversize books, to magazines and small pocket books.
The present invention is a door-operated page turner or reading aid for able-bodied and disabled persons unable to use or preferring not to use his or her hands. The door-operated page turner device includes a platform that supports a plurality of transparent doors that open and close and are used for turning and holding the pages of reading material in a fixed open position while providing an unobstructed view of the page.
The pages of the reading material can be turned with a low-cost tool similar to an eraser-tipped pencil. Once disengaged, a page pops up enough to allow the reader to use the plurality of doors to turn that page to its new position. For the disabled person who is lacking manual dexterity, the tool can be readily adapted to the existing gripping prosthetic devices suitable for that disability. Once turned, the page or pages are held in place by a plurality of transparent doors that cover the compartment that holds stacked reading pages in a fixed open position.
A preferred page turning system for hands-free reading of books includes a box having an open top, sides and a bottom, a left transparent lid being slidably attached to cover a left portion of the open top, a right transparent lid being slidably attached to cover a right portion of the open top, a spacer for keeping the left transparent lid and the right transparent lid spaced apart less than approximately 0.5 inch when the left transparent lid and the right transparent lid are in a closed position covering the open top of the box, a reading material having a front cover, a back cover and a plurality of stacked reading pages between the front and back covers, the bottom of the box supporting the reading material in an open position with the front cover overlaying a left portion of the bottom of the box, and the back cover with the plurality of stacked reading pages overlaying a right portion of the bottom of the box, a single protruding member with a tip, wherein the tip of the protruding member is adapted to slide the right transparent lid to the right exposing a first page of the stacked reading pages, and the tip is used to lift up an outer edge of the first page to be above the right transparent lid, followed by the tip of the protruding member pushing against and sliding the right transparent lid to slide to the left until the right transparent lid abuts against the spacer, wherein the tip of the protruding member pushes both the closed left and right transparent lids to the left until the raised first page is overlaying the left portion of the bottom of the box.
A more preferred page turning system has a spacer that allows for keeping the left transparent lid and the right transparent lid spaced apart approximately ⅛ of an inch when the left transparent lid and the right transparent lid are in a closed position covering the open top of the box. It is also preferred that at least one of the left transparent lid and the right transparent lid has a beveled edge that abuts against the spacer. Most preferably, the right transparent lid has a beveled edge that abuts against the spacer.
The preferred page turning system of the present invention also includes a left set of tracks for slidably attaching the left transparent lid to the open top of the box and a right set of tracks for slidably attaching the right transparent lid to the open top of the box.
It is also preferred that the page turning system include height adjustment members for adjusting distance between the left and right transparent lids to the bottom of the box. In addition, it is preferred to have height adjustment members on the left lower sides and right lower sides attached to the bottom of the box which slide about the sides of the box and openings at different heights along the left lower sides and the right lower sides and dowels for being inserted in the different height openings for separating the left and right transparent lids from the bottom of the box for different sizes of reading materials. The height adjustment members for use with reading materials such as books, magazines, and the like, having different thicknesses.
The preferred reading material for the page turning system of the present invention is a magazine or a book. The preferred protruding member with the tip for the page turning system is a pencil with an eraser tip or the tip is adapted to be a human nose or a human finger.
A preferred method for turning pages in a bound volume so that reading is accomplished hands-free includes providing a reading material with a front cover, a back cover and a stack of reading pages between the front and back cover, providing a box having an open top, closed sides and a platform as a bottom of the box, providing a single protruding member with a tip, then opening the reading material so that the front cover is supported on a left portion of the platform and the back cover with the stack of reading pages is supported on a right portion of the platform, slidably covering a left portion of the open top of the box with a left transparent lid, slidably covering a right portion of the open top of the box with a right transparent lid.
The method can include spacing the left transparent lid apart from the right transparent lid so that an opening is no greater than approximately 0.5 inch (preferably approximately ⅛ of an inch) when the left transparent lid and the right transparent lid are in a starting closed position on the top of the box, pressing the tip of the protruding member against a portion of the right transparent lid, slidably moving the right transparent lid to the right with the tip of the protruding member exposing a first page of the stacked reading pages, raising an outer exposed edge of the first page of the stacked reading pages with the tip of the protruding member, allowing the outer exposed edge of the first page to protrude above and come to rest against a portion of the right transparent lid, slidably moving the right transparent lid to the left with the tip of the protruding member until the left transparent lid and the right transparent lid are in a closed position with the first page of the stacked reading pages sandwiched in the opening between the right transparent lid and the left transparent lid.
The method can include continuing the movement of the right transparent lid to the left until the first page slips through the opening between the closed right transparent lid and left transparent lid and the raised first page is overlaying the left portion of the bottom of the box, slidably returning both the closed left and right transparent lids with an opening no greater than approximately 0.5 inch (preferably approximately ⅛ of an inch) to the starting closed position on the top of the box, and repeating the above steps to expose each additional stacked page.
The preferred reading material in the method for turning pages is a magazine or a book. The preferred single protruding member with the tip used in the method for turning pages is a pencil with an eraser tip or is a tip adapted to be a human nose or a human finger. Additionally, the reader can use their pursed lips to move the lids and/or the pages.
Further objects and advantages of this invention will be apparent from the following detailed description of the presently preferred embodiments, which are illustrated schematically in the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a front perspective view of a first embodiment of the novel page turner device with book opened inside and back cover clamped in place.
FIG. 2 is a front perspective view of the novel page turner device of FIG. 1 with book opened inside and all pages moved over clamped back cover except for the front cover.
FIG. 3 is another perspective view of the page turner device of FIG. 1 with height setting knobs.
FIG. 4 is another perspective view of the platform with attached open book separated from the outer box of the page turner device of FIG. 1 .
FIG. 5 is an exploded view of the platform with attached book and box of the preceding figures.
FIG. 6 is a perspective view of the box and platform with attached book with right and left transparent lids separated from the box.
FIG. 7 shows a first page edge of the platform attached book in the box of the preceding figures, being lifted and raised over the left edge of the right transparent lid.
FIG. 8 shows another view of the page turning device of FIG. 7 with the right lid being moved to the left along arrow Y to catch under the first page of platform attached book.
FIG. 9 shows both the left lid and right lid moving in unison to the left along arrow Y, of the page turning device of FIG. 8 with the first page moving from the right side of the box to the left side of the box by slipping through the gap between the left and right transparent lids.
FIG. 10 shows the left and right transparent lids of the box of FIG. 9 moved in the direction of arrow X so the first page is on the left side and the second page is on the right side of the box.
FIG. 11 is an exploded view of another page turning device embodiment of FIG. 5 with wing extensions.
FIG. 12 is another view of the page turning device of FIG. 11 with attached wing extensions and transparent lids separated.
FIG. 13 is another view of the page turning device embodiment of FIG. 11 a first page edge of the platform attached book in the box of the preceding figures, being lifted and raised over the left edge of the right transparent lid.
FIG. 14 is another view of the page turning device of FIG. 13 with the right lid being moved to the left along arrow Y to catch under the first page of platform attached book.
FIG. 15 shows both the left lid and right lid moving in unison to the left along arrow Y, of the page turning device of FIG. 14 with the first page moving from the right side of the box to the left side of the box by slipping through the gap between the left and right transparent lids.
FIG. 16 shows the left and right transparent lids of the box of FIG. 15 moved in the direction of arrow X so the first page is on the left side and the second page is on the right side of the box.
FIG. 17 shows an enlarged side view of the height adjusting knobs of the first embodiment.
FIG. 18 shows an enlarged side view of the height adjusting knobs of the second embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Before explaining the disclosed embodiments of the present invention in detail, it is to be understood that the invention is not limited in its application to the details of the particular arrangements shown since the invention is capable of further embodiments. Also, the terminology used herein is for the purpose of description and not of limitation.
In the description of the present invention, the term “book” or “books” will represent all reading matter, including magazines, atlases, brochures, catalogs, manuals, manuscripts and any other matter being examined visually.
Other terms used herein are defined as follows.
“Binding” to mean the spine, cover and end papers of a bound volume.
“Gutter” is the white space formed in the inner margins of two facing pages of a bound publication.
“Paperback” is a book bound in a flexible, paper cover.
“Platform” is a square or rectangular, three-dimensional, open-face case for supporting an open book in a generally upright angled orientation.
“Spine” is the hinged back of a book.
A listing of the components will now be described.
a, b left knobs a′, b′ right knobs c upper groove d bottom groove e dowel insert f dowel insert 12 bottomless box with sides 14 right transparent lid 16 left transparent lid 18 platform with downward extending sides 20 book 20 a first page of book 20 b back of first page of book 22 spacer gap 24 decorative trim to form spacer gap 30 spring loaded clip/clamp to hold down back cover 32 probe with tip/finger/nose 100 first embodiment of page turning device 200 second embodiment of page turning device 212 box with sides 218 platform 214 right transparent lid 216 left transparent lid 232 probe with tip/finger/nose 240 left wing extension 250 right wing extension 260 optional openings in left lid 270 optional openings in right lid
Embodiment 1 of the present invention 100 is described in FIGS. 1-10 and 17 . Embodiment 2 of the present invention 200 is described in FIGS. 11-16 and 18 . The common features for all embodiments include the platform or case for supporting an open book in a generally upright angled orientation and the base stands or props to hold the platform or case in an angled orientation. The slidably removable dowel support rods that support the open box top of each embodiment above the platform that holds the reading material are shown in FIGS. 18 and 19 . A person skilled in the art can readily devise additional embodiments by interchanging and rearranging the elements disclosed herein. Therefore, the embodiments disclosed are not to be considered a limitation of the present invention.
FIG. 1 shows a front perspective view of the door-operated page turning device 100 having a bottomless box 12 with four sides resting on dowel rods with knobs a, b along the right side edges of box 12 . A right transparent lid or door 14 and a left transparent lid or door 16 are in a closed position in the tongue and groove channels c, d in the upper and lower sides of the box 12 . The terms “lid” and “door” are used interchangeably herein to mean the portion of the present device that opens and closes while turning pages of reading material. The bottomless box with sides 12 covers a platform 18 that holds or supports an open book. Platform 18 has holes for the insertion of the dowel rods with knobs a, b. A spacer gap 22 of less than approximately 0.5 inch (preferably approximately ⅛ of an inch) is between the left transparent lid and the right transparent lid in the closed position to facilitate the opening and closing of the transparent lid when the lids are used to turn a page of a book 20 .
FIG. 1 also shows an optional decorative trim 24 around the outer edges of the transparent right and left lids 14 , 16 . The decorative trim 24 is useful in providing a raised surface for leverage in slidably moving the lids and creating the spacer gap 22 . The trim is useful to let the lids move more smoothly on the surface of the box than the lids moving relative to the grooves. The left lid has trim portions that extend to the right to contact the right lid, so that when the right and lid trim portions meet together, they create the space gap therebetween. The trim is also raised and is further useful for the reader to move the lids. The trim also can add a bit of decoration to cover the plain edges of the box lids.
FIG. 1 shows an initial position of opening a book 20 on platform so that the back cover is clamped in place by clamp 30 of the right side of the platform with front cover and all the pages are on the left side of the platform.
In FIG. 2 , all the stacked pages are moved to the right over the clamped back cover so that only the front cover of the book 20 is on the left side of the platform 18 .
FIG. 3 is a partially exploded front perspective view of the door-operated page turning device 100 showing the supporting legs of platform 18 with symmetrically aligned and vertically positioned holes to adjust the height of the bottomless box 12 using dowel rods with knobs a, b on the left side and dowel rods with knobs a′, b′ on the right side of platform 18 .
FIG. 4 is a front perspective view of the platform 18 of the door-operated page turning device 100 showing flat surface of the platform 18 with a clamp 30 to hold a back cover of the book 20 securely in place and the slidably removable dowel rods with knobs a, a′, b, b′ that can be adjusted to raise or lower the door-operated page turning device on the bottomless box 12 .
FIG. 5 is a partially exploded front perspective view of the door-operated page turning device 100 with bottomless box 12 in position to be lowered onto platform 18 with dowel rods a, a′, b, b′ in the holes in a first position.
FIG. 6 is a plan view of the door-operated page turning device 100 when the bottomless box 12 is positioned over platform 18 , resting on dowel rods with knobs a, b (a′,b′ not shown). The right transparent lid 14 and left transparent lid 16 , are in the process of being aligned to be slidably moved along the tongue and groove channels c, d of box 12 in the direction of arrows X and Y, respectively.
FIGS. 7-19 show the door-operated page turning device 100 being used to turn pages of an open book supported on the flat surface of platform 18 .
FIG. 7 shows the left transparent lid 16 of the door-operated page turning device 100 in alignment with the left edge of box 12 . The right transparent lid 14 of the door-operated page turning device is slidably moved to the right to partially expose a first page 20 a of book 20 . A probe or any protruding member with a tip 32 is used to lift or raise an outer edge of first page 20 a from the stack of pages in book 20 . By only partially exposing the first page, the rest of the stacked pages are not prone to easily flip up. The probe can include a pencil with eraser tip, a stick, and the like. Furthermore, a body part such as but not limited to a finger or a nose can also be used. Still furthermore, pursed lips can be used to move the lids and/or to move the pages.
The next step for turning a page using the door-operated page turning device is shown in FIG. 8 where probe or protruding member with a tip 32 is used to guide the outer edge of page 20 a onto the outer surface of the right transparent lid 14 , as lid 14 is slidably moved toward the left transparent lid 16 capturing the page in the spacer gap 22 . Here, upper and lower right protruding trim portions of trim 24 on the left lid 14 extend to the right to allow for capturing and aligning each additional page being raised and lifted.
FIG. 9 shows the spacer gap 22 with the page 20 a sandwiched between the left and right transparent lids and being turned to expose the second page 20 b of book 20 on the right side of platform 18 while first page moves to a new position overlaying the left side of the flat surface of platform 18 . Here, the back page 20 b of the first page of the book is now on the left side of the platform. In FIG. 9 , the left and right lids 14 , 16 can be moved to the left along arrow Y with the previous probe 32 abutting against a top or right edge of the right lid 16 .
FIG. 10 shows the left and right transparent lids 14 and 16 with spacer gap 22 positioned over the gutter of book 20 and holding the pages in place until the reader decides to turn them. Here, the reader can now read the back of the first page and the front of the second page. Reading additional pages can also be done by repeating the steps outlined above in reference to FIGS. 7-9 .
The invention has great applicability to those with arthritis, weak hand grasping capability, and others not able to easily grip books, that may have difficulty physically holding a book, and having to turn a page.
The invention can be used with readers have no hands or arms, where the reader can move the transparent lids with their nose or chin, and move the pages with pursed lips. Additionally, the lids can be also moved with pursed lips.
FIG. 11 provides an exploded view of the second embodiment 200 of the door-operated page turning device with platform 218 and bottomless box 212 in position to be fitted over platform 218 and held securely by dowel rods with knobs a,a′,b,b′ that are slidingly engaged in vertically positioned holes that receive the dowel end of the rod. The new features of the second embodiment are the added wing extensions 240 , 250 each with a tongue and groove channel that matches the channels c and d of box 212 . The wing extensions 240 , 250 are attached to the upper edge of box 212 with dowel inserts e and f. The wing extensions 240 , 250 allow for the easy expansion of the range of motion for the transparent lids that open and close in the turning of pages. The wings can support the lids the lids are being moved beyond the right and left sides of the box.
FIG. 12 is a plan view of the door-operated page turning device 200 with wing extensions 240 , 250 securely in place and left transparent lid 216 and right transparent lid 214 in position to be moved slidingly along the channels c and d of box 212 . Note there are optional openings 260 , 270 in the upper and/or bottom portions of each of the transparent lids facilitate the use probe or protruding member with a tip previously described (not shown) to easily open and close the sliding transparent doors. Additionally, the openings 260 , 270 allow the use of body parts such as the tip of a reader's nose to more easily move the lids. Furthermore, pursed lips of the reader can also be inserted partially into the openings to allow for moving the lids.
FIG. 13 shows the door-operated page turning device 200 where the left transparent lid 216 of the door-operated page turning device 200 is in alignment with the left edge of box 212 . The right transparent lid 214 of the door-operated page turning device is slidably moved to the right to partially expose a first page 210 a of book 210 . A probe or any protruding member with a tip 232 is used to lift or raise page 210 a from the stack of pages in book 210 . Also, as previously discussed, a body part such as a pursed lips can also be used to move the pages.
The next step for turning a page using the door-operated page turning device is shown in FIG. 14 where a probe or protruding member with a tip 232 is used to guide the outer edge of page 210 a above an onto the outer surface of the right transparent lid 214 . After the user lifts page 210 a from book 210 using a protruding member with a tip 232 , page 210 a pops up towards the user and the outer edge comes to rest on the outer surface of the right transparent lid 214 . Lid of door 214 is slidably moved toward in the direction of arrow Y toward the left transparent lid 216 capturing the page 210 a in the spacer gap 222 shown in FIG. 15 .
FIG. 15 shows the spacer gap 222 with the page 210 a sandwiched between the left and right transparent lids and being turned to expose the second page 210 b of book 210 in a new position overlaying the left side of the flat surface of platform 218 . Similar to the previous embodiment the probe 232 can be used to move both the lids to the left.
FIG. 17 shows the left and right transparent lids 216 and 214 in position after being moved as a single unit in the direction of arrow X of FIG. 16 along the tongue and groove channels c, d of box 212 . A protruding member with a tip (not shown) can be used to slidingly move both the left and right transparent lids 214 and 216 , respectively, into a position that covers the open surface of box 212 , as shown in FIG. 17 where the left and right transparent lids 214 and 216 are covering the turned page 210 b and the next page 210 c to be turned by repeating steps shown in FIGS. 13 , 14 and 15 above.
Common features of both embodiments of the present invention are now discussed below. Common to both embodiments is a probe or protruding object with a tip for opening and closing the left and right transparent lids and lifting or raising the pages to be turned from a stacked position in a book, magazine or the like. The protruding object with a tip, includes, but is not limited to, a pencil with an eraser tip, and the like. Furthermore, a human body part can be used such as a human nose, human finger, pursed lips, or a prosthetic device used by a handicapped individual.
Another common feature of both embodiments is shown in FIGS. 18 and 19 and is related to the adjustable positioning mechanism used to raise or lower the bottomless box with the sliding transparent lids or doors to accommodate the thickness of a book or other reading material placed on the flat surface of the platform that is covered by the bottomless box. In FIG. 17 , a cross-sectional view of platform 18 shows the insertion of dowel rod with a knob a to serve as a support in holding the bottomless box 12 in a selected position. FIG. 18 is a cross-sectional view of the platform 218 that shows the more penetrating insertion of dowel rod with knob a further into the platform 218 so that the bottomless box 212 is raised to a slightly higher position over the platform 218 . It is understood that a plurality of dowel rod and knob supports are positioned in appropriate hole positions about the platform to allow the bottomless box to rest squarely and securely on the supports.
While the preferred embodiment shows a spring loaded clamp/clip on the right side of the platform, the invention can also have a spring loaded clamp/clip on the left side of the platform to hold down the front cover page. The invention can also work with both left and right spring loaded clamps. While the spring loaded clamps enhance holding reading material such as paperback books, magazines in place, the invention can be used without the spring loaded clamps for reading material such as hard cover books, and the like.
The present invention provides an easy to manufacture, easy to assemble and easy to use door-operated page turning device for hands-free reading of books of all kinds from hard covered books, mechanical bound books, magazines, sheet music, paperbacks, bound sheets of paper, manuals and the like.
While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended. | Door/lid operated page turner devices, systems and methods for reading materials such as books is provided for hands-free reading for the able-bodied and disabled reader. A platform supports a book that is covered by a bottomless box having an open top, with left and right transparent lids slidably attached to cover the open top with a small space between the lids when closed. A single protruding member with a tip is adapted to slide the right transparent lid to the right exposing a page of the stacked reading pages, the tip is also used to lift up an outer edge of the page to be above the right transparent lid, followed by the tip of the protruding member pushing against and sliding the right transparent lid to the left until the right transparent lid abuts against the spacer, wherein the tip of the protruding member pushes both the closed left and right transparent lids to the left until the raised first page is turned and overlaying the left portion of the supporting platform. The user slides the closed pair of transparent lids back to align the spacer gap between the doors with the center of the book thereby fixing the turned page into a new position. Protruding members such as a nose can move the lids, and pursed lips can move pages with the device. Additionally, other protruding members such as pencils can be used. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to a trace element analyzer employing a plasma, such as a plasma emission spectrometer or a plasma mass analyzer, and, more particularly, to an improved plasma analyzer for trace element analysis, capable of efficiently changing a gas supplied to a plasma and of efficiently mixing the gas in the plasma.
A representative example of a conventional plasma analyzer employing a plasma is disclosed, for example, in Japanese Patent Laid-open (Kokai) No. 64-6351. Shown in FIG. 4 are an argon (Ar) gas source 1a, a nitrogen (N 2 ) gas source 1b, first, second and third flow meters 2a, 2b and 2c eahc provided with a valve, fourth, fifth and sixth flowmeters 3a 3b and 3c each provided with a valve, a triple-tube plasma torch 4 having an outer chamber 4a, a middle chamber 4b and an inner chamber 4c, a coil 5, a plasma 6, a sample vessel 7, a nebulizer 8, a high frequency power source 9, a sampling cone 10, a skimmer 11, vacuum pumps 12a, 12b and 12c, a mass filter 13, a detector 14 and a signal processing unit 15.
The basic operation of this conventional plasma analyzer will be described hereinafter. In an initial state, the valves of the first to third flowmeters 2a to 2c are open respectively in openings allowing corresponding gases to flow at given flow rates, respectively, and the valves of the fourth to sixth flowmeters 3a to 3c are closed. In this state, Ar gas is supplied into the outer chamber 4a and the middle chamber 4b of the plasma torch 4 through the flowmeters 2a and 2b, respectively. A sample nebulized by the nebulizer 8 is carried by Ar gas supplied as a carrier gas through the flowmeter 2c into the inner chamber 4c of the plasma torch 4. The respective flow rates of the Ar gas supplied respectively into the outer chamber 4a, the middle chamber 4b and the inner chamber 4c are regulated by the valves of the flowmeters 2a, 2b and 2c, respectively. Then, the coil 5 is energized by high frequency power supplied by the high frequency power source 9 to generate the plasma 6 by the agency of a high frequency magnetic field created by the coil 5. Ions produced in the plasma are drawn through the sampling cone 10 and the skimmer 11 into a vacuum chamber, in which the ions are analyzed by the mass filter 13 and are detected by the detector 14. A detection signal provided by the detector 14 is sent to and processed by the signal processing unit 15 to obtain mass analysis data. The mass analysis data is used for drawing a mass spectrum by a recorder.
After thus generating the plasma by using Ar gas, the valves of the fourth to sixth flowmeters 3a to 3c are opened gradually to supply N 2 gas at given flow rates through the fourth to sixth flowmeters 3a to 3c into the outer chamber 4a, middle chamber 4b and inner chamber 4c of the plasma torch 4, so that Ar-N 2 mixed gases of different mixing ratios are supplied respectively into the outer chamber 4a and middle chamber 4b of the plasma torch 4, and an Ar-N 2 mixed gas serving as a carrier gas is supplied together with the nebulized sample nebulized by the nebulizer 8 into the inner chamber 4c of the plasma torch 4.
Then, the values of the flowmeters 2a to 2c are regulated to decrease the flow rates of the Ar gas gradually, monitoring the mass spectrum so that the peak of Ar and the peak of the objective element may not coincide with each other. If the respective peaks of Ar and the objective element coincide with each other, the valves of the flowmeters 3a to 3c are regulated so as to increase the flow rates of the N 2 gas so that the respective peaks of Ar and the objective element are separated from each other. Upon the separation of the respective peaks of Ar and the objective element, the gas compositions respectively in the outer chamber 4a, the middle chamber 4b and the inner chamber 4c are sustained.
Thus, the Ar gas mixed in the plasma is changed for N 2 gas to enable the measurement of the objective element without being disturbed by argon-related molecular ions.
Incidentally, it is possible that the plasma vanishes if the Ar gas is changed suddenly for N 2 gas in changing the gas mixed in the plasma. Therefore, the Ar gas must be changed gradually for N 2 gas to sustain the plasma. Nevertheless, the conventional plasma analyzer is not provided with satisfactory means for facilitate the gas changing operation and requires delicate operation for the adjustment of the valves of a plurality of flowmeters in combination with monitoring the mass spectrum, which requires much time and labor. Thus, the conventional plasma analyzer has problems in measuring efficiency and accessibility.
SUMMARY OF THE INVENTION
The present invention has been made to solve those problems in the conventional plasma analyzer, and it is therefore an object of the present invention to provide an improved plasma analyzer for trace element analysis, capable of enabling simple, efficient operation for changing the gas mixed in the plasma and for adjusting the composition of the gas.
In one aspect of the present invention, a plasma analyzer for trace element analysis is provided with a gas supply system for supplying gasses into a plasma, comprising a plurality of gas sources, solenoid valves connected respectively to the gas sources, buffer tanks respectively connected to the solenoid valves, and flow regulating flowmeters respectively connected to the buffer tanks.
Although the solenoid valves operate in an on-off mode to change the respective flow rates of the corresponding gases suddenly, the buffer takes suppress the sharp variation of gas flows so that the respective flows rates of the gases may change gradually. Accordingly, the composition of the gas supplied into the plasma changes gradually even if the flow of the component gases changes sharply due to the simple on-off operation of the solenoid valves, so that the extinction and fluctuation of the plasma due to the sudden change of the composition of the gas supplied into the plasma can be effectively prevented. Since troublesome flow rate adjusting operation including the delicate adjustment of the valves of a plurality of flowmeters is not necessary, the plasma analyzer of the present invention is readily accessible and is capable of efficiently carrying out operation for trace element analysis.
The above and other objects, features and advantages of the present invention will become more apparent from the following description taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a gas supply system incorporated into a microwave-induced plasma analyzer for trace element analysis in a preferred embodiment according to the present invention;
FIG. 2 (2a, 2b and 2c) is a time chart of assistance in explaining the basic actions of the gas supply system of FIG. 1;
FIG. 3 is a block diagram of the microwave-induced plasma analyzer incorporating the gas supply system of FIG. 1; and
FIG. 4 is a diagrammatic view of a conventional plasma analyzer for trace element analysis.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 showing a gas supply stream incorporated into a plasma analyzer for trace element analysis in a preferred embodiment according to the present invention, an electromagnetic valve 16a and a buffer tank 17a (or a pipe of an equivalent volume) are provided on a line connecting a first flow regulating flowmeter 18a to a first gas source 1a, for example, an Ar gas cylinder, and an electromagnetic valve 16b and a buffer tank 17b (or a pipe of an equivalent volume) are provided on a line connecting a second flow regulating flowmeter 18b to a second gas source 1b, for example, a N 2 cylinder. The electromagnetic valves 16a and 16b are controlled by a computer 20. In FIG. 1, indicated at 19 is a plasma torch.
The buffer tanks 17a and 17b buffer sudden changes in the composition and pressure of a gas supplied to the plasma torch 19 due to the operation of the electromagnetic valves 16a and 16b in an on-off mode. Even if the electromagnetic valve 16a is closed instantaneously, the buffer tank 17a makes the flow rate of Ar gas supplied to the plasma torch 19 decrease gradually instead of immediately dropping to zero. On the other hand, even if the electromagnetic valve 16b is opened instantaneously, the buffer tank 17b makes the flow rate of N 2 gas increase gradually instead of sharply increasing to a maximum. Thus, the composition of the gas supplied to the plasma torch 19 changes gradually, so that the plasma does not fluctuate or does not extinct in changing the gas from Ar gas to N 2 gas. Similarly, the sudden change in the composition of the gas is prevented in changing the gas from N 2 gas to Ar gas. A time necessary for changing the composition of the gas can be determined selectively by selectively determining the respective capacities of the buffer tanks 17a and 17b.
This gas composition changing operation will be described with reference to a time chart shown in FIG. 2. In an initial state, the electromagnetic valve 16a is ON and the electromagnetic valve 16b is OFF as shown in FIGS. 2(a) and 2(b) to supply only Ar gas to the plasma torch 19 at a predetermined flow rate Q A (1 to 20 l/min) regulated by the flow regulating flowmeter 18a as shown in FIG. 2(c) and an Ar plasma is generated by the plasma torch 19. At time t 1 , the electromagnetic valve 16b is turned ON to supply N 2 gas to the plasma torch 19 at a predetermined flow rate Q N (1 to 20 l/min) regulated by the flow regulating flowmeter 18b. The buffer tank 17b suppresses the instantaneous increase of the flow rate of N 2 gas flow zero to Q N at time t 1 so that the flow rate of N 2 gas increases gradually. After the flow rate of N 2 gas has arrived at the predetermined flow rate Q N , the electromagnetic valve 16a is turned OFF at time t 2 to stop supplying Ar gas, and then the buffer tank 17a decreases the flow rate of Ar gas gradually. Consequently, the composition of the gas supplied to the plasma torch 19 changes gradually from an Ar-rich composition to a N 2 -rich composition. At time t 3 , the flow rate of Ar gas reaches zero and only N 2 gas is supplied to the plasma torch 19. Thus, the N 2 concentration of the gas supplied to the plasma torch 19 starts increasing from zero at time t 1 , increases gradually between time t 1 and t 2 , reaches 100% at time t 3 , and only N 2 gas is supplied after time t 3 . Thus, the plasma changes gradually from the Ar gas plasma to a N 2 gas plasma between time t 1 and time t 3 .
The N 2 gas plasma is changed for the Ar gas plasma in the following manner. Before time T 4 , the electromagnetic valve 16a is OFF and the electromagnetic valve 16b is ON to supply only N 2 gas to the plasma torch 19. At time t 4 , the electromagnetic valve 16a is turned ON to start supplying Ar gas, and then the flow rate of Ar gas increases gradually. Upon the arrival of the flow rate of Ar gas at the predetermined flow rate Q A regulated by the flow regulating flowmeter 18a, the electromagnetic valve 16b is turned OFF at time t 5 and, consequently, the flow rate of N 2 gas decreases gradually to zero to time t 6 , so that the plasma changed from the N 2 gas plasma to an Ar gas plasma.
The flow rate Q A of Ar gas in supplying only Ar gas to the plasma torch 19 and the flow rate Q N of N 2 gas in supplying only N 2 gas to the plasma torch 19 may be determined optionally by the flow regulating flowmeters 18a and 18b according to plasma generating conditons including the high frequency power, the microwave power and the configuration of the plasma torch 19. Generally, in changing over the plasma between an Ar gas plasma and a N 2 gas (or air) plasma, it is desirable that the flow rate Q A of Ar gas is in the range of 1 to 3 l/min, the flow rate Q N of N 2 gas is in the range of 8 to 10 l/min, and Q A <Q N , when, for example, the microwave power W=1 kW and the plasma torch 19 has an inner tube having an inside diameter d=10 mm.
A time T 1 and a time T 2 necessary for perfectly changing the plasma from an Ar gas plasma to a N 2 gas plasma, and from a N 2 gas plasma to an Ar gas plasma, respectively, can be optionally determined by adjusting the respective volumes of the buffer tanks 17a and 17b provided that other conditions are fixed. Usually, the times T 1 and T 2 are determined selectively in the range of 1 to 30 sec so that the plasma may not fluctuate or may not extinct.
Sequential control of the electromagnetic valves 16a and 16b by the computer 20 facilitates changing the gas supplied to the plasma torch 19.
Referring to FIG. 3 showing a plasma analyzer for trace element analysis in a preferred embodiment according to the present invention, there are shown an Ar gas source 1a, a N 2 gas source 1b, a plasma torch 4, electromagnetic valves 16a, 16b, 16c and 16d, buffer tanks 17a, 17b, 17c and 17d (or pipes of equivalent volumes), flow regulating flow meters 18a, 18b, 18c and 18d, microwave oscillator 21 for generating microwave power, a microwave cavity 22 of a surface wave type or a circularly polarized wave type through which microwave power is supplied to the plasma torch 4, and a microcomputer for controlling the electromagnetic valves 16a to 16d, the microwave oscillator 21 and a signal processor 15. The plasma torch 4 is of a double-tube construction having an inner tube 41 and an outer tube 42. A carrier gas and a sample is supplied into the inner tube 41, and a plasma is introduced into the annular space between the inner tube 41 and the outer tube 42.
The plasma analyzer operates in the following manner. all the electromagnetic valves 16a to 16d are OFF before the plasma analyzer is started. In starting the plasma analyzer, the electromagnetic valve 16a is turned ON to supply a plasma gas (Ar gas) through the buffer tank 17a and the flow regulating flowmeter 18a into the annular space between the inner tube 41 and outer tube 42 of the plasma torch 4, and the electromagnetic valve 16c is turned ON the supply a carrier gas (Ar gas) through the buffer tank 17c and the flow regulating flowmeter 18c to a nebulizer 8. A sample supplied from a sample vessel 7 to the nebulizer 8 is nebulized by the nebulizer 8 and is supplied together with the carrier gas into the inner tube 41 of the plasma torch 4. Subsequently, the microwave oscillator 21 is started to supply microwave power through the microwave cavity 22 to the plasma torch 4 to generate a plasma 6. Ions of the sample produced in the plasma 6 are drawn through a sampling cone 10 and a skimmer 11 into a vacuum chamber, are condensed by a lens system 23, are filtered by a mass filter 13 and are detected by a detector 14. The detector 14 gives a detection signal to the signal processor 15, which processes the detection signal to provide data for drawing a mass spectrum.
After the Ar gas plasma has been produced, the electromagnetic valve 16b is turned ON to mix N 2 gas supplied through the buffer tank 17b and the flow regulating flowmeter 18b in the plasma gas (Ar gas) in the space between the inner tube 41 and outer tube 42 of the plasma torch 4, and the electromagnetic valve 16d is turned ON to mix N 2 gas supplied through the buffer tank 17d and the flow regulating flowmeter 18d in the carrier gas (Ar gas) in the nebulizer 8. Although the electromagnetic valves 16b and 16d are turned ON suddenly, the buffer tanks 17b and 17b suppress the sharp increase in the flow rate of N 2 gas to increase the the same gradually as shown in FIG. 3.
Upon the increase of the flow rate of N 2 gas supplied to the plasma torch 4 and that of N 2 gas supplied to the nebulizer 8 to predetermined flow rates regulated by the flow regulating flowmeters 18b and 18d, respectively, the electromagnetic valves 16a and 16b are turned OFF to stop supplying Ar gas, in which the buffer tank 17a and 17c suppress the sharp decrease in the flow rates of Ar gas so that the flow rates decreases gradually as shown in FIG. 3. Eventually, only N 2 gas is supplied as the plasma gas and the carrier gas.
Since the plasma gas and the carrier gas are changed gradually from Ar gas to N 2 gas, the plasma neither fluctiates nor extincts during the change of Ar gas for N 2 gas, and the measurement of objective elements is achieved stably and accurately without being disturbed by argon-related molecular ions.
In changing the plasma gas and the carrier gas from N 2 gas to Ar gas, the electromagnetic valves 16b and 16d are turned OFF a short time after the electromagnetic valves 16a and 16c have been turned ON.
All the foregoing operations are controlled according to a sequentially control program by the microcomputer 20. The carrier gas (Ar gas) may be supplied to the plasma torch 4 after generating an Ar plasma in the plasma torch 4 or the plasma gas (Ar gas) and the carrier gas (Ar gas) may be supplied simultaneously to the plasma torch 4. In changing the gases supplied to the plasma torch 4, the timing of operating the electromagnetic valve 16a of the plasma gas supply system and that of operating the electromagnetic valve 16c of the carrier gas supply system need not necessarily coincide with each other; there may be a time lag between the operation of the electromagnetic valve 16a and that of the electromagnetic valve 16c. The same timing mode applies to the timing of operating the electromagnetic valve 16b and that of operating the electromagnetic valve 16d. Although the timing of turning OFF the electromagnetic valve 16a is delayed relative to the timing of turning ON the electromagnetic valve 16b in changing the Ar gas for N 2 gas, and the timing of turning OFF the electromagnetic valve 16b is delayed relative to the timing of turning ON the electromagnetic valve 16a in changing N 2 gas for Ar gas in the exemplary mode of operation of the plasma analyzer as described above with reference to FIG. 2, the electromagnetic valves 16a and 16b may be operated simultaneously.
Although the manner of changing the plasma gas and the carrier gas between Ar gas and N 2 gas has been described, the gases to be used by the present invention are not limited to Ar gas and N 2 gas. When a gas which is more difficult to generate a plasma than Ar gas, such as helium gas (He gas), oxygen gas (O 2 gas) or air, is used, Ar gas is supplied first to produce an Ar plasma, and then Ar gas may be changed for He gas, O 2 gas or air. The gas supplied to the plasma torch 4 need not necessarily be changed from pure Ar gas through a Ar-N 2 mixed gas to pure N 2 gas; the gas may be, for example, a gas of 5% Ar and 95% N 2 .
Means for generating the plasma is not limited only to microwave power; high frequency power or dc power may be used for generating the plasma.
As is apparent from the foregoing description, according to the present invention, the composition of the gas supplied into the plasma can be efficiently changed, and the plasma analyzer for trace element analysis is accessible. Since the plasma analyzer of the present invention is capable of readily generating a plasma of a gas difficult to produce a plasma under the atmospheric pressure, such as N 2 gas, He gas on air, inexpensive N 2 gas on air may be used instead of expensive Ar gas. Furthermore, the trace elements contained in the sample can be accurately analyzed, because the highly accurate separation and detection of disturbed ions, i.e., ions of the same mass, disturbed by the gas of the plasma is possible. | A plasma analyzer for trace element analysis has a gas supply system comprising a plurality of gas sources, an electromagnetic valve provided on a line connecting each gas source to a plasma generating space, a buffer tank provided after the electromagnetic valve on the line, and a flow regulating flowmeter provided after the buffer tank on the line. Each electromagnetic valves is controlled for on-off operation and the corresponding buffer tank suppresses the sudden change of the flow rate of the corresponding gas, so that the composition of the gas supplied to the plasma generating space changes gradually in spite of the simple on-off operation of the electromagnetic valves. Thus, the fluctuation and extinction of the plasma attributable to the sudden change of the composition of the gas supplied to the plasma generating space can be effectively prevented. | 6 |
FIELD OF THE INVENTION
This invention relates to optical filters and more particularly, to narrow band-pass optical filter and method of fabrication.
BACKGROUND OF THE INVENTION
There have been many attempts to develop compact, high precision, low tolerance narrow band optical filters centered at predetermined wavelengths for application in areas such as spectroscopy, optical networks and optical links, and more particularly optical communication systems. Optical filters are some of the most ubiquitous of all passive optical components found in most optical communication systems. One use of optical filters is in the field of optical communications where only a signal of a predetermined wavelength is to be passed.
Narrow band optical filters which pass only a very narrow band of light (e.g. ±0.2 nanometers or less) and centered at a predetermined wavelength, are extremely difficult to make and consequently relatively expensive to manufacture. As of late, there has been a demand for a plurality of such filters having a wavelength separation of less than 2 nanometers. One known means for providing a selective narrow band optical filter, is by utilizing a wavelength selective interference filter element whose wavelength characteristic depends on the angle of incidence. Thus, by varying the angle of light incident upon the interference filter, the wavelength of the light that is passed by the filter varies. Such a filter element is described in U.S. Pat. No. 5,331,651 issued Jul. 19, 1994 and assigned to the Hewlett-Packard Company. Often, these filter elements are used in free-space configurations, wherein a beam of light exiting an optical fiber or other waveguide is directed through free space into a wavelength selective interference filter element at a predetermined angle; however, many such configurations have limitations. For example, positioning and affixing an optical fiber in a predetermined position and at a predetermined angle relative to a filter element can be challenging.
Thus, it is an object of this invention, to provide an integrated narrow band-pass filter and method of making a filter, which overcomes many of the limitations in prior art devices, and, wherein the device is compact, centered at a predetermined frequency, and has a tolerance that is within very small predetermined limits.
It is a further object of the invention to provide a method of tuning a filter to obtain a wavelength selective filter that is compact and centered at a predetermined frequency within very small predetermined limits.
SUMMARY OF THE INVENTION
In accordance with the invention, an optical filter is provided comprising first and second graded index lenses disposed in a coaxial relationship, the lenses having a common optical axis. Each of the lenses have an endface providing a port at predetermined location. The ports are disposed on opposite sides of the optical axis; each of the ports is substantially equidistant from the optical axis, so as to be oppositely offset from the optical axis by a same amount. The filter also includes wavelength selective means disposed between the other endfaces of the first and second graded index lenses; the wavelength selective means have a wavelength characteristic dependent upon on an angle of incidence for transmitting light of a predetermined wavelength and reflecting other wavelengths.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention will be described in conjunction with the drawings in which:
FIG. 1 is an illustration prior art graded index (GRIN) lens showing the principles of operation;
FIG. 2a is an illustration of two quarter pitch GRIN lenses illustrating their operation;
FIG. 2b is a filter dement having wavelength characteristics that vary with angle of incidence;
FIG. 3a is a side view of two quarter pitch GRIN lenses having a filter element disposed therebetween;
FIG. 3b is an illustration of a two port narrow bandpass filter in accordance with the invention;
FIG. 3c is an illustration of a four port narrow bandpass filter in accordance with the invention;
FIG. 3d is an illustration of an alternative embodiment of the bandpass filter shown in FIG. 3c;
FIG. 3e is an illustration of an alternative embodiment of the bandpass filter shown in FIG. 3d;
FIG. 3f is an illustration of a multi-port narrow bandpass filter in accordance with the invention;
FIG. 3g is an illustration of an alternative embodiment of the bandpass filter having input and output ports an a same side of the optical axis; and,
FIG. 4 is an illustration of an alterative embodiment of the bandpass filter shown in FIG. 3a.
DETAILED DESCRIPTION
In the following description, it should be understood that same elements shown in different figures are assigned same reference numerals. Referring now to FIG. 1, a 1.0 pitch GRIN lens 10 is shown having an input beam represented by an upright arrow at an input endface 12 of the lens 10. Fiber lenses of this type are produced under the trade name "SELFOC"; the mark is registered in Japan and owned by the Nippon Sheet and Glass Co. Ltd. At a location along the lens, indicated as 0.25 pitch, the input beam becomes collimated. At the 0.5 pitch location midway between the endfaces of the lens 10, the input beam becomes inverted. This phenomenon is further demonstrated in FIG. 2. However, two matched quarter pitch GRIN lenses 14a and 14b are disposed in a back to back relationship. Each GRIN lens is provided with a port which is a point or region along an endface of the lens for receiving or transmitting a beam of light. The beam shown by an upright arrow at the input port 12a of lens 14a is inverted at the output port 12b of the second GRIN lens 14b.
Turning now to FIG. 2b, a wavelength selective means 32 in the form of a narrow band interference filter, is shown; the interference filter 32 has a wavelength characteristic dependent upon on an angle α of incidence. In the figure an input beam of light comprised of three wavelengths λ 1 , λ 2 , and λ 3 is incident upon the filter 32. Since the filter passes a predetermined wavelength of light at a predetermined angle, in the example, λ 1 and λ 3 are reflected and λ 2 is passed through the filter 32. Of course, varying the angle of incidence α varies the wavelength of light passed, the filter reflecting other wavelengths outside of a very narrow band about the center wavelength. In attempting to manufacture a narrow band filter using the interference filter 32 shown in FIG. 2b, it is very difficult to accurately glue an optical fiber to an optical element such as a filter, at a predetermined angle. Furthermore, it is difficult to adjust and maintain the angle α in a controlled manner in the process of manufacturing a discrete component.
In FIG. 3a, a optical filter 20 includes a first quarter pitch GRIN lens 14a and second GRIN lens 14b oriented as in FIG. 2. The GRIN lenses are disposed in a coaxial relationship having a common optical axis 34. A filter 32 is disposed between the inwardly facing endfaces of the first and second graded index lenses 14a and 14b. Light at the inwardly facing end faces at the filter 32 is collimated by the lenses. By placing a pair of waveguides, for example in the form of optical fibers at outward endfaces of the filter 30 (shown in FIG. 3b) input output ports 36a and 36b respectively are provided. As a result of the input beam being inverted by the GRIN lens 14a, an input beam launched into input port 36a on one side of the optical axis 34 propagates through the device 30 and exits the output port 36b on the other side of the optical axis. Thus, if the lenses 14a and 14b are symmetrical, it is necessary to ensure that the ports 36a and 36b juxtaposed on either side of the optical axis 34 are substantially equidistant from the optical axis. In one method of manufacture, one of the ports can be moved slowly toward or away from the optical axis 34 in a controlled manner until a detected output signal is at a maximum intensity. When the ports are adjusted sufficiently, or it is deemed that the light launched into the port 36a is focused onto the output port 36b, the filter 30 can be tuned to a desired wavelength within the physical limits of the filter 32. For example, when the two ports are adjusted as was described heretofore, the filter 30 will function as a narrow bandpass filter, passing a very narrow band of light having a spectral width that is within a predetermined maximum. Essentially, a signal having predetermined center wavelength and a variance from that predetermined wavelength of a predetermined small mount, will pass through the filter. For example, in one embodiment of this invention four filters are tuned, respectively, to pass 1550±0.2 nm, 1552±0.2 nm, 1554±0.2 nm, and 1556±0.2 nm. By displacing the fibers (i.e. ports 36a and 36b) a small same amount and direction, toward or away from the optical axis, the center frequency of the filter changes. As the fibers are displaced, moving further away from the optical axis, the wavelength of the narrow band filter 30 decreases, and thus, aligning the ports 36a and 36b with the optical axis will provide a filter with a maximum wavelength. In FIG. 3b a beam 37 is incident upon the filter 32 at an angle α. As the position of the ports is moved toward the optical axis the angle α decreases and the center wavelength increases.
Alternative embodiments to the basic filter of FIG. 3b, will now be described with reference to FIGS. 3c to 3f. For example, in FIG. 3c a filter 40 is comprised of the same elements as those described in FIG. 3b including two additional ports 38a and 38b. Thus, filter 40 comprises two narrow band filters in a single device. In operation a signal comprising wavelengths λ 1 , λ 2 , and λ 3 is launched into input port 36a. Only wavelength components of the signal centered about λ 3 are received at the output port 36b. By symmetry, when a signal having wavelength components of λ 4 , λ 5 , λ 6 is launched into input optical fiber 38a only wavelength components of the signal centered about and near λ 6 are received at the output port 38b. In FIG. 3d, the interference filter 32 is disposed at an angle Φ, further increasing the angle of incidence and hence further increasing the shorter range wavelength range in which the filter can be tuned. With reference to FIG. 3e, in order to lessen unwanted back reflections, the outwardly facing endfaces of the lenses 14a and 14b are angled. The endfaces of the optical fibers are polished to a complementary angle to mate with the angled endfaces of the lenses. FIG. 3f shows a multi-port multi-lensed embodiment of a filter 60, wherein two lenses which may be identical or have different characteristics are utilized with a the interference filter 32. Ganging the lenses in this manner provides a filter that is capable of separating a plurality of light into 4 separate wavelength channels.
The method of fabricating the filters described heretofore in accordance with this invention, will now be described with reference to the more basic embodiment of FIG. 3b. An optical filter 30 includes two lenses 14a and 14b coaxially positioned with a wavelength selective means 32 disposed therebetween, and two ports 36a and 36b. The ports are located on opposing sides of the optical axis 34 and substantially equidistant therefrom. Polychromatic light such as white light is launched into the optical filter 30 through the port 36a. It is angled by the lens 14a as shown at 37 so as to pass through the wavelength selective means 32 at an angle α before being received at the port 36b. The angle α is determined by the location of the ports 36a and 36b relative to the optical axis 34. The ports 36a and 36b are then moved relative to the optical axis 34 thereby changing the angle α until the desired center frequency is being received at the port 36b. The two ports 36a and 36b are then positioned so as to increase the intensity of the received light. The entire optical filter is then bound in this position with glue or another suitable binder. This fixes the frequency response of the filter to that desired.
In an alternative embodiment shown in FIG. 4, the optical filter includes two lenses which are not coaxially situated. The lens 14b is positioned such that the axis 34b is parallel to the axis 34a of the lens 14a but offset by a lateral distance. The light entering the lens 14a at the port 36a is collimated and passes through the wavelength selective means 32 at an angle α. The collimated light enters the lens 14b some distance from the wavelength selective means 32 and is focused onto the port 36b.
In a further alternative embodiment shown in FIG. 3g the optical filter includes two lenses which are dissimilar. The lenses are chosen to cooperate to provide an intended optical path. The lens 14c is a 0.75 pitch GRIN lens. The lens 14b is a 0.25 pitch GRIN lens. Thus light entering the lens 14c through the port 36a is collimated and passes through the wavelength selective means 32 at an angle α, dependent upon the location of the port 36a. The light is focused by the lens 14b onto the port 36b on a same side of the optical axis 34. In some instances this embodiment provides particular advantages. For example, it may be easier to adjust the position of two optical ports on a same side of the optical axis 34.
Of course, numerous other embodiments may be envisaged, without departing from the spirit and scope of this invention, for example, the wavelength selective means disposed between the endfaces of the two lenses may be in the form of a coating applied to one of the inwardly facing endfaces of one of the lenses. | An optical filter is provided having first and second graded index (GRIN) lenses preferably disposed in a coaxial relationship so that they have a common optical axis. Each of the GRIN lenses have an endface providing a port at predetermined location. The ports are disposed on opposite sides of the optical axis and each of the ports are substantially equidistant from the optical axis, so as to be oppositely offset from the optical axis by a same amount. The filter also includes an optical interference filter disposed between other endfaces of the first and second graded index lenses. By changing the location of the ports by a same small amount, the center wavelength of the filter changes by a small amount, thus in manufacture, the filter is tunable. After tuning the filter to a desired wavelength, the locations of the ports are fixed. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to human growth hormone therapy and to the cure of human disease through organ and tissue transplantation. The present invention includes a method for regenerating the human thymus to allow intrathymic transplantation and thereby the elimination of organ and tissue rejection. There are two variations of this method, one that employs growth hormone and one that employs agent that can substitute for growth hormone's thymus-regenerating effects. The former method has wide applicability beyond the transplantation of tissues and organs, because it involves the elimination of the most important side effects of growth hormone. Human growth hormone (HGH) has been recognized as a treatment for children of short stature or with renal failure, and has been a safe and effective treatment in most cases, but there are several reports that such children often experience hyperinsulinemia as a result of HGH administration. Further, HGH has been considered as a powerful approach to the treatment of human aging, but its widespread use is inhibited by its serious side effects, the most important of which is elevation of fasting and glucose-stimulated insulin levels, a phenomenon that is known to be a risk factor for atherosclerosis and cardiovascular disease. Arginine, an HGH releaser, has therapeutic effects in its own right, but has the same drawback of elevating blood insulin levels. The invention described here permits HGH therapy to be administered with no elevation in blood levels of insulin.
[0002] Much has been written of late about the growing excitement of anti-aging (gerolytic) therapies, including hormone replacement therapy with dehydroepiandrosterone (DHEA), melatonin, sex hormones, thyroid hormone, cordsol, or human growth hormone. Of these, the work of Rudman has attracted the most attention because of his statement that administration of human growth hormone (HGH) produced the same effects as the reversal of 20 years of aging. Rudman and others have, in fact, amassed an impressive body of evidence indicating that it is the loss of HGH with age that is responsible for much of the human aging process, including atrophy of internal body organs, thinning of the skin, slowing of cell division, weakening of muscles and bones, and accumulation of body fat. Even immune system decline with age seems largely dependent on loss of HGH. Furthermore, GH administration to animals produces a radical increase in longevity.
[0003] On the other hand, Marcus et al. have shown the down side of HGH: given at the minimum doses used in Marcus' study, equivalent to the doses used by Rudman, HGH produced dramatic and disturbing rises in fasting and stimulated serum insulin levels. The administration of HGH is known to decrease the body's sensitivity (i.e., responsiveness) to insulin, thus causing a compensating rise in pancreatic insulin output and therefore in serum insulin levels; yet paradoxically, falling HGH levels in aging humans are accompanied by increasing serum insulin levels.
[0004] Elevated insulin, in turn, has been linked in many studies and via many mechanisms to the development of atherosclerosis, hypertension, and heart disease. It is absolutely a major factor holding back the widespread clinical application of HGH for combatting many of the maladies of aging, dimming the attraction of this otherwise spectacular anti-aging intervention. HGH also leads to mild rises in serum cholesterol and triglycerides, raises blood pressure, and may produce symptoms similar to arthritis.
[0005] Of all the developments in modem immunology that promise to make the rejection of transplanted cells, tissues, and organs obsolete, the most exciting is the technique of intrathymic transplantation pioneered by Naji et al. This is so because the method requires no specific attention to the details of the rejection process, can be applied to the transplantation of virtually any tissue or organ into virtually any recipient, probably including even transplantation between unrelated species, without complex tailor-made immunopharmaceuticals, and with minimal trauma to the recipient, and can reverse established autoimmune disorders including autoimmune diabetes. The method involves first transplanting a biopsy sample of the graft into the thymus of the recipient and then transplanting the graft itself after a predetermined time. The presence of the intrathymic biopsy renders the host tolerant to the graft itself, either by eliminating or anergizing immune cells that attack the biopsy in the thymus. In addition, it is likely that, in the case of autoimmunity, the host can be made tolerant of its own tissue again by transplanting it into the thymus, thus reversing autoimmunity. Contrary to the presumption that tolerization will require a longer time than the ex vivo lifetime of the graft to be transplanted, recent studies have shown that success can be achieved when kidneys are transplanted into the recipient within 24 hours of the time the renal biopsy is placed into the recipient's thymus. Rejection is suppressed in the short run by a single dose of antilymphocyte globulin and/or by other conventional immunosuppression until tolerization makes further immunosuppression unnecessary. Bone marrow transplantation is also believed to induce tolerance to subsequent grafts from the same donor by the migration of bone marrow cells into the thymus, an equivalent process to transplantation of actual organ tissue samples in the thymus.
[0006] The main problem with this method is that it requires a functioning thymus gland of significant mass in order To be effective. The human thymus begins to involute before the age of 20 and becomes severely atrophied by the age of 40, and transplant surgeons and immunologists are at a loss for a way of overcoming this problem. In fact, it is thought that age-related thymic involution accounts for a major part of age-related morbidity and mortality and therefore represents a major unsolved health problem worthy of solution in its own right.
[0007] What has not been recognized by the medical community is that thymic regeneration is possible in humans. Many animal studies attest to the feasibility of thymic regeneration in animals using several different methods. Several human studies have shown that immune system function can be restored in older humans, but it has never been suggested that this is due to thymic regeneration. The present invention effects thymic regeneration in man.
[0008] Several methods have been shown capable of reversing thymic involution in animals and, by inference, in man, but none are feasible for human use. Administering a male contraceptive to rats results in dramatic thymic regeneration, but would not be desirable in humans for a variety of reasons, including major testicular shrinkage. It has been recognized that hyperthyroid humans do not undergo age-related thymic involution, and that administration of thyroid hormone to older humans results in a restoration of youthful indices of immune system function, but administration of thyroid hormone is considered hazardous, and hyperthyroid individuals have a number of medical problems. The problems of regenerating the thymus of diabetic animals or humans have not been considered at all in the prior art.
[0009] As noted above, the use of growth hormone alone for this purpose would be contraindicated by the adverse effect of growth hormone on insulin sensitivity, despite the ability of growth hormone to regenerate the thymus in rodents and dogs and to improve immunity in older humans. Growth hormone use for thymic regeneration could lead to unacceptable loss of control of insulin responsiveness in diabetics and elevated insulin levels in nondiabetics. In fact, since elevated insulin leads to virtually all of the side effects of growth hormone (hypertension, atherosclerosis, water retention, and cardiovascular morbidity), it is possible that most of these side effects are a result, at least in part, of the elevation of insulin produced by growth hormone.
SUMMARY OF THE INVENTION
[0010] In the present invention, it has been surprisingly discovered that one can increase a patient's level of human growth hormone without causing a corresponding increase in serum insulin levels by administering either human growth hormone (HGH) or its equivalent (active HGH analog, HGH metabolite or fragment, HGH mimic, HGH releaser or mixtures thereof) in combination with dehydroepiandrosterone (DHEA) or its equivalent (DHEA-sulfate, other DHEA precursor, DHEA releaser, DHEA metabolite(s), DHEA equivalent analog, or mixtures thereof). (Here we define a “mimic” as a structurally dissimilar compound that has the same biologic action as the natural biological molecule.) This is surprising, in that human data militate against an insulin-suppressing effect of DHEA in normal people, and suggest that DHEA administration can actually elevate insulin levels indirectly.
[0011] In another aspect of the invention, it has been surprisingly determined that in addition to effecting other positive results associated with human growth hormone treatment, the above regimen can permit the cure of diabetes and a range of other diseases by actually regenerating the human thymus and thereby allowing subsequent intrathymic transplantation.
[0012] These and other objects, advantages and features of the present invention will be more fully understood and appreciated by reference to the appended specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] [0013]FIG. 1 charts serum fasting glucose and fasting insulin levels against serum DHEA-sulfate levels in an arginine (HGH releaser) administration experiment involving DHEA administration;
[0014] [0014]FIG. 2 charts the relative change in insulin level against the relative change in serum DHEA-sulfate level in the same experiment as FIG. 1;
[0015] [0015]FIG. 3 graphs DHEA serum concentration against serum concentration for DHEA-sulfate;
[0016] [0016]FIG. 4 compares the correlation between insulin level and either DHEA concentration or testosterone concentration, FIG. 5 charts the blood serum level of IGF-1 against time in an arginine and DHEA administration experiment;
[0017] [0017]FIG. 6 charts serum insulin, IGF-1 and DHEA against time, during a protocol involving administration of HGH and DHEA.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
General Procedure
[0018] In the preferred embodiment, human growth hormone (HGH) or its equivalent analog, metabolite, fragment, releaser, mimic, or mixture thereof is administered by subcutaneous injection or other efficacious route every day or every other day or three times a week (e.g., Monday, Wednesday and Friday) at an HGH equivalent dose of 0.01 to 0.05 mg/kg of body weight, the dose being adjusted to avoid peak levels of growth hormone or somatomedin C greater than those found in individuals that are 10-30 years of age. (Peak levels similar to those 10-20 years of age are appropriate for thymic regeneration; levels similar to those of 20-30 year olds are appropriate for chronic growth hormone replacement therapy.)
[0019] The most desirable target range for somatomedin C levels in men and women for long-term growth hormone replacement therapy is 700-3000 units/L, and particularly 1000-1600 units/L (where 1 unit equals 150 ng of somatomedin C). For short-term thymus regeneration, the target somatomedin C levels are 700-7000 (most preferably 700-5000) units/L for women and 700-6000 (most preferably 700-3000) units/L for men. Simultaneously with or slightly before HGH administration, DHEA, DHEA precursor (such as DHEA-S), DHEA releaser, equivalent metabolite, equivalent DHEA analog or a mixture thereof is given orally or via another efficacious route at a DHEA equivalent dose of 50-2000 mg, more preferably 50-1000 mg/day, the dose being adjusted based on the circulating DHEA level (not to exceed levels found in individuals 20-25 years of age by more than 100%) and the response of circulating insulin levels (insulin levels should be adjusted by DHEA dose until they are at or below the pre-HGH insulin basal levels). The most desirable target range for circulating DHEA is 300-800 ng/dl. This regimen should be continued preferably for 1-3 months before intrathymic transplantation, and/or indefinitely for applications related to aging or growth.
[0020] The term HGH is intended to include recombinant or natural human growth hormone. HGH releasers are compounds which stimulate the body's production and/or release of HGH and include, but are not limited to, growth hormone releasing hormone (GHRH), clonidine, phenylalanine, L-DOPA, arginine, ornithine, deprenyl, and somatostatin inhibitors. HGH will be effective whether it is supplied exogenously or released from the pituitary by such releasing agents. Consequently, the use of a growth hormone releaser is an acceptable variation on the use of growth hormone itself, in those patients who are able to release adequate growth hormone in response to such agents. Patients who are able to release appreciable but not sufficient HGH in response to such agents may be given both a releasing agent and exogenous HGH so as to attain the required HGH levels for thymic regeneration while minimizing the use of exogenous HGH, which is expected to be more expensive than HGH releasers. Furthermore, the entire HGH molecule may not be required for HGH action. Therefore, equivalent analogs such as genetically-engineered variants or fragments of HGH that retain the biological activity of HGH but that are less expensive or have fewer side effects are also acceptable variations. The dosage for any of these HGH alternatives are “HGH equivalent doses,” that is they should yield the same desired level of or effect of HGH in the body. An example of an HGH “mimic” would be somatomedin C. The best mode process is also compatible with administration of drugs that block other side affects of HIGH, e.g., parlodel to block gynecomastia in men.
[0021] DHEA should be given “to effect.” “To effect” is defined as sufficient to lower that particular patient's insulin levels down to either basal levels or, if basal levels are elevated in comparison to an accepted standard for good health and long life, to levels deemed to maximize longevity and health. Typically, this will involve most preferably DHEA doses of 50-1000 mg/day, a range considerably below the “overkill” doses of 1600 to 2500 mg/day being employed routinely in human clinical trials, which maximize the danger of complications such as masculinization of women or worsening of benign prostatic hypertrophy in men. All routes of administration fall within the limits of the best mode process, and the substitution of any DHEA precursor, releaser (such as an enzyme that cleaves DHEA-S to “release” DHEA), equivalent DHEA metabolite or equivalent analog of DHEA that has the same insulin-suppressing role as DHEA itself constitutes an acceptable variation, including combinations of DHEA and agents that block any undesired effects of DHEA.
[0022] DHEA-sulfate is an example of a DHEA precursor. Although DHEA is considered to be active and DHEA-sulfate to be inactive, tissue enzymes exist that convert DHEA-sulfate into DHEA in the body. Consequently, DHEA-sulfate rather than DHEA itself may be administered in a dose appropriate to raise DHEA levels to insulin-suppressing values (or to produce similar insulin suppression directly). The term DHEA releaser is intended to include any other compound which causes the body to produce or release DHEA in the body. The dosage required for any of the alternatives to DHEA per se should be “DHEA equivalent doses,” that is, doses that yield the same insulin lowering effect as the indicated doses of DHEA.
[0023] The precise mechanism of operation of the preferred embodiment is not known. DHEA does not simply eliminate excess insulin, and indeed that would be undesirable, since the increased insulin level is in response to the body's reduced insulin sensitivity. Rather, DHEA apparently directly counters the desensitizing effects of HGH, thus allowing the body to obtain the same glucose uptake with lower, indeed normal, insulin levels.
[0024] Adding DHEA to counter the insulin-raising effects of growth hormone is compatible with the use of any drugs that may be developed that limit the conversion of DHEA to masculinizing androgens in either women or men or otherwise suppress DHEA or DHEA-sulfate side effects. The optimum dose of DHEA is that dose that successfully suppresses insulin to the desired level and maximizes subsidiary benefits such as inhibition of atherosclerosis without producing side effects.
[0025] The time of DHEA administration is optimally close to the time of administration of HIGH so that DHEA will be present in the blood stream when the insulin-elevating tendency of HGH is maximal. For example, oral arginine taken just before bedtime should be accompanied by DHEA. A pharmaceutical agent consisting of HGH+DHEA or HGH releaser+DHEA or HGH analog+DHEA or any of these HGH variants+DHEA analogs or DHEA-sulfate, etc., would embody this best mode approach. However, the process of using DHEA to suppress insulin includes administration at other times as well. The effects of HGH on human physiology last approximately six months or more. Consequently, administration of DHEA or its equivalent to suppress insulin elevated by previous HGH administration or its equivalent is valid at any time insulin is elevated by prior HGH or HGH equivalent administration.
EXPERIMENTAL RESULTS
Experiment 1
[0026] Administration Of Arginine (An HGH Releaser) And DHEA
[0027] A human patient was placed on a standardized regimen of nutrient intake for two weeks to establish a baseline prior to ingesting any HGH releasing agents. The evening prior to blood analysis, the same evening meal was consumed (salmon, potato, white wine, vegetables, and Caesar salad). Upon establishing basal values for glucose, insulin, somatomedin C (a marker for growth hormone), DHEA-sulfate, serum lipids, and testosterone, a daily regimen of ingesting 15 grams of arginine just before bedtime was instituted. This regimen was maintained for one week, after which a new baseline was obtained. The evening following this new baseline measurement, DHEA was ingested at a dose of 180 mg (two 90 mg capsules taken simultaneously) at the same time as the arginine. This was continued for one week and the baseline levels of metabolites were rechecked. Finally, for the last week, the arginine dose was administered every other day or at 7.5 g/day while DHEA levels were maintained. Thus, the data points are as follows:
[0028] 1: Baseline—begin 15 gm/day administration of arginine;
[0029] 2: Day 7—begin 180 mg/day DHEA;
[0030] 3: Day 14—begin 15 gm arginine every other day or 7.5 g/day; and
[0031] 4: Day 21-end of experiment, no arginine administered the previous night.
[0032] The primary results are given in FIG. 1 and FIG. 2, which document the changes in insulin and glucose levels that accompanied the introduction and tapering off of arginine administration and their relationship to DHEA (reflected in FIG. 1 by DHEA-sulfate due to a missing basal value for DHEA itself). There was no change in glucose concentration, which is consistent with the known lack of effect of HGH on glucose concentrations. On the other hand, fasting serum insulin rose nearly 50% in response to arginine ingestion (point 2), but was brought down to only 76% of basal levels by the ingestion of DHEA, despite the continuing and undiminished administration of arginine (point 3). This data point thus provides the crucial validation of the hypothesis and the key to removing the side effects of HGH administration. Point 4 gives the result of dropping arginine administration to a regimen of every other day ingestion, no ingestion having taken place the night prior to the blood analysis represented. Here insulin has returned to basal levels. The significance of this point is that it shows the combination of HGH release and DHEA administration regimens that precisely balances the effects of these two hormones on insulin levels.
[0033] There are two other aspects of FIGS. 1 and 2 that seem significant. First, accompanying the elevation of insulin that results from arginine ingestion (point 2 versus point 1) is a noticeable increase in DHEA-sulfate. This is an endogenous increase, since no DHEA was ingested over this period, and establishes a putative link between the release of HGH and DHEA. This link is confirmed by comparing points 3 and 4, which show that, with no drop in DHEA ingestion, the circulating level of DHEA-sulfate fell in response to the fall in arginine ingestion. From these results, it would appear that DHEA levels are normally modulated by growth hormone so as to buffer the effects of growth hormone on insulin. This is consistent with animal studies showing a DHEA-releasing effect of growth hormone. With aging, DHEA levels become insufficient to carry out this function, since DHEA falls faster with age than does HGH, and a rise in insulin is thus expected.
[0034] [0034]FIG. 3 shows the correlation between DHEA-sulfate and DHEA in this study. The correlation appears adequate to use in assuming that the DHEA-sulfate levels shown in FIG. 1 reflect DHEA levels.
[0035] [0035]FIG. 4 presents evidence that the effect of DHEA is due to DHEA itself rather than testosterone, which rises upon DHEA administration and has been linked to insulin sensitivity in women with polycystic ovarian syndrome. FIG. 4 shows that the correlation between insulin and DHEA is far better than the correlation between insulin and testosterone, contrary to previous results with these women. (Lines are least squares regression fits.)
[0036] [0036]FIG. 5 shows a paradoxical result, namely, an actual DROP, as opposed to the expected RISE, in somatomedin C (also known as IGF-1) levels in response to oral arginine. This drop was sustained as long as arginine administration was continued. An independent experiment confirmed this IGF-1lowering effect of arginine: basal levels of 223 ng/ml fell to 166 ng/ml two hours after arginine ingestion. Direct addition of arginine to the serum sample to determine whether arginine interferes with the chemical assay for IGF-1 indicated that 4 mM arginine made IGF-1 levels read higher than 1 mM arginine in the serum, not lower, arguing that the IGF-1-lowering effect is real, not artifactual. Others have also measured somatomedin C levels following arginine ingestion or infusion, and found them to be depressed despite good release of HGH. There is no explanation for this paradox, but it is not material to the fact that HGH is released by arginine and that released HGH does elevate insulin and that DHEA does block this insulin-elevating effect.
[0037] Arginine is known to be a secretagogue for insulin in its own right, and the possibility that it could be responsible for a major part of the insulin elevation observed must be considered. However, this possibility appears unlikely for the following reasons. First, the time course of insulin elevation in humans following arginine ingestion or infusion is rapid: insulin levels peak in about 30 minutes or less and fall back to baseline within 1-2 hours, whereas in the experiment reported in FIG. 1, insulin was measured 11-13 hours after arginine ingestion. Insulin at that late tune could only have been affected by long-term secondary effects of arginine ingestion, i.e., HGH release and its resulting insulin elevation, which takes more than 6 hours to fully develop. Further, in the experiment described in FIG. 1, an insulin determination after only 3 days of arginine ingestion revealed a normal insulin level (data not shown in FIG. 1), indicating that it is not the acute and direct insulin-releasing effect of arginine that is primarily responsible for the insulin elevation observed, but insulin resistance derived from delayed arginine-induced HGH release.
Experiment 2
[0038] Administration Of HGH And DHEA
[0039] The above-described experiment is based on the generally accepted assumption and observation that arginine activates the endogenous release of HGH. This second experiment was conducted to confirm comparable results from the direct administration of HGH.
[0040] As in the first experiment, a standard dietary regimen was followed the evening before each blood sample was collected. HGH administration was initiated one day after a baseline blood sample was drawn. HGH was injected subcutaneously at a dose of approximately 0.018 mg/kg/day, every other night, and was injected near midnight prior to blood collection the following morning. Blood was collected between 10:30 and 11:00 a.m. The second blood sample was taken on day 8, or just over 7 days after beginning HGH injections (4 injections in total to that time). After this second blood sample, a “wash out” period of two days was allowed prior to reinitiating injections according to the same schedule. On day 9, during the HGH “wash out” period, a priming dose of 200 mg of DHEA was taken in divided doses to prepare the patient for the HGH. The second round of injections was done simultaneously with the ingestion of two 100 mg capsules of DHEA, beginning on the evening of day 10. This regimen continued for a total of 4 HGH injections, culminating in the final injection on day 16 and blood sampling on day 17. Two hundred mg of DHEA were taken also on the nights between HGH injections, at the normal time. HGH injections were administered near midnight of the day stated.
[0041] The results of this experiment are shown in FIG. 6 and Table 1. The effects on insulin are virtually identical to those of the original arginine experiment, insulin rising by 57% prior to DHEA ingestion and falling to 101.5% of control levels after combining HGH with DHEA. Therefore, there is no doubt of the antihyperinsulinemic effect of DHEA in the presence of hyperinsulinemia inducing doses of HGH, a phenomenon that has never before been documented or suspected. Further, there is no doubt that currently recommended doses of HGH do produce a serious hyperinsulinemia effect. HGH actually depressed circulating DHEA levels by a third while leaving DHEA-sulfate unaltered; this is presumably a manifestation of the well-known DHEA-depressing effect of insulin, and is different from the net DHEA-sulfate-elevating effect, and apparent DHEA-elevating effect, of arginine administration documented above. This may reflect the depressed IGF-1 levels in the arginine protocol versus the elevated IGF-1 levels with HGH administration, and is explicable if IGF-1 (“insulin-like” growth factor) contributes to the suppression of DHEA by a mechanism similar to that of insulin. Regardless, the large change in DHEA level farther supports functional interrelationships between HGH and DHEA. In fact, it is fascinating that DHEA appears to govern the differential effects of HGH on IGF-1 versus insulin, allowing IGF-1 to rise with HGH administration (desirable) while insulin remains unchanged (desirable) despite the similarities of the two. The exact data for all metabolites measured are reported in Table 1.
TABLE 1 Level Stage of HGH Metabolite Experiment: Baseline only HGH + DHEA Insulin (uU/ml) 6.6 10.4 6.7 IGF-1 (ug/dl) 27.0 35.5 37.1 DHEA (ng/dl) 360 240 530 DHEA-sulfate (ug/dl) 146 146 688
[0042] Direct Applications Of DHEA And HGH Coadministration
[0043] Some obvious implications of the successful reversal of the most troubling side effect of HGH administration, the rise in serum insulin and the fall in insulin sensitivity, are (a) the ability to use HGH in many more normal individuals for the direct treatment of aging with minimal fear of side effects, (b) the ability to use HGH in older diabetics, whose need for HGH probably exceeds that of normal elderly individuals but whose ability to take HGH would be ruled out by most physicians in the absence of a means of normalizing insulin sensitivity, and (c) the ability to use HGH to treat younger people suffering from both pituitary insufficiency and adrenal insufficiency. The combination of DHEA and arginine may also be useful when arginine is used in doses below the HGH-releasing dose to stimulate immunity or when arginine is used as a laxative or for other purposes. The applications mentioned also pertain to the physiological equivalents of HGH+DHEA.
[0044] Curing Diabetes With HGH And DHEA Coadminstration
[0045] A nonobvious application is to cure diseases such as diabetes. The key to this application is the ability to use DHEA+HGH to regenerate the human thymus. Most age-related immune system decline is caused by thymic involution (atrophy). Thymic involution is not now a clinically treatable condition, and it affects virtually 100% of the adult population. The concurrent administration of human growth hormone or an HGH releaser and DHEA, its metabolites or equivalent analogs surprisingly reverses thymic involution in older individuals and in others with thymic insufficiency.
[0046] By regenerating the previously atrophied thymus, this coadministration of HIGH and DHEA allows intrathymic transplantation in elderly or involuted individuals as a route to permanent grafting of tissues and organs without immunosuppression and without rejection, a technique not formerly applicable to those over the age of 30-40 or to those patients with atrophied thymuses (e.g., hypothyroid patients). Three immediate applications of this method are the cure of insulin dependent diabetes, the reversal of autoimmune conditions in those over 30, and the engrafting of older individuals with organs or with genetically engineered cells and tissues from unrelated sources without rejection and without chronic immunosuppression.
[0047] The regimen for administering human growth hormone and DHEA or their equivalents for the rejuvenation of the thymus is as described above in the preferred embodiment. The regimen should be continued preferably for 1-3 months. For best results, this regimen can be supplemented with other immune-system strengthening agents, particularly coenzyme Q 10 (10-200 mg/day), Vitamin E (200-1000 IU/day) and zinc (30-100 mg/day). Further, chromium picolinate (100-1000 micrograms/day) may be used to supplement DHEA/DHEA-sulfate.
[0048] After thymic regeneration, the thymus should be imaged (preferably by magnetic resonance imaging, though other methods are also acceptable) to verify regeneration and thymic location. Surgery should then take place on the same day as or the day after HGH and DHEA are administered according to the protocol specified above. At this time, a surgeon skilled at thymic biopsy retrieval injects into the thymus an appropriate sample of the tissue or organ to be transplanted later, or injects any other donor-specific cells or antigens (for example, bone marrow cells) that are the immunological equivalent of the tissue itself in stimulating deletion or anergy of the cells otherwise responsible for later rejecting the transplanted tissue or organ. This tissue may be an endogenously-derived sample in the case of those with autoimmune diseases, e.g., myelin from the cauda eqina to reverse multiple sclerosis; a joint biopsy to reverse autoimmune arthritis; or endogenous islets to reverse incipient diabetes in the case of diabetes that has not progressed to the point of major islet die-off. The amount of injected tissue is equivalent to {fraction (1/10)}th to twice the amount specified by Naji's prior art for animals without thymic atrophy (based on the ratio of thymic volume to volume of the injected tissue and/or on the ratio of the volume of injected tissue to body weight). A variation on direct intrathymic injection is peripheral injection of cells that spontaneously migrate to the regenerated thymus (e.g., bone marrow cells) and thus induce tolerance.
[0049] At the same time the intrathymic or peripheral injection is given, the patient is given a standard dose of antilymphocyte globulin or other appropriate immunosuppressant to ensure persistence of the intrathymic graft until the recipient's immune system becomes tolerant of the donor's tissues. The desired tissue or organ transplant itself may be given on the same day as the intrathymic injection, accompanied by maintenance immunosuppression until tolerance is attained, or this transplantation may be delayed until tolerance is attained, in order to avoid the need for immunosuppression lasting longer than 1-2 weeks, or to avoid the need for higher doses of immunosuppressants.
[0050] In the case of curing diabetes, it is desirable to inject pancreatic islets into the thymus in order to be able to judge the “take” of injected material based on islet function and in order to attain some preliminary minimal protection from diabetes prior to the subsequent transplantation of islets by infusion into the portal vein or other site.
[0051] In the case of reversing autoimmunity, the priming injection to the thymus need not be followed by further transplants unless an additional intrathymic endogenous tissue sample is required to facilitate reversal of the autoimmune state. For such patients, anti-rejection medication should be used sparingly or not at all.
[0052] Alternative Embodiments For Thymic Regeneration
[0053] In broader aspects of thymic regeneration to facilitate thymic injection and subsequent organ and tissue transplantation, alternative methods for regenerating the thymus can be utilized. First, insulin sensitizing (and therefore lowering) agents other than DHEA and its above-described relatives can be employed in place of DHEA. Chromium picolinate and similar formulae involving chromium (such as “GTF” or glucose tolerance factor preparations available in health food stores) and phenformin represent the only known members of this class of agents. As in the case of DHEA, the appropriate dose is to be adjusted based on the insulin-lowering response attained in a particular patient. Chromium picolinate is particularly exciting because of its low toxicity, its ability to extend the life span of animals by 50%, and because its ability to increase insulin sensitivity is a key anti-aging effect. The action of chromium picolinate is not considered to be similar to the actions of DHEA in humans in the prior art because the insulin-lowering effect of DHEA is unknown in the prior art. Although the ability of chromium picolinate to reverse GH-induced elevation of insulin levels has been reported in passing in pigs, its use in regenerating the thymus has never been contemplated in the prior art, the further application of this regeneration to tissue and organ transplantation has similarly never been previously contemplated, and its use in combination with HGH for these ends has also not been contemplated in the prior art.
[0054] A last approach to regenerating the thymus is to use agents other than the equivalent of HGH and DHEA, whose thymus-regenerating effect substitutes for that of growth hormone but does not involve elevation of insulin levels. In particular, the use of zinc alone, Vitamin E alone, or coenzyme Q 10 alone have shown promise in restoring immune system function in elderly animals and humans. The use of all three agents together provides an improved method of stimulating immunity that will regenerate the thymus sufficiently to permit subsequent intrathymic transplants without producing undesirable effects on insulin sensitivity. Consequently, a third choice for thymic regeneration is to use 30-130 mg/day of zinc plus 200-1000 IU/day of Vitamin E plus 10-200 mg/day of coenzyme Q 10 for 1-3 months. This approach will be desirable when HGH and DHEA or their equivalents cannot be used for any reason.
[0055] Of course, it is understood that the foregoing are merely preferred embodiments of the invention and that various changes and alterations can be made without depart from the spirit and broader aspects thereof, as set forth in the appended claims. | Human growth hormone therapy and thynic regeneration are effected by the generally simultaneous administration of one of human growth hormone, its analogs, precursors, metabolites, releasers or mixtures thereof in combination with one of DHEA, its precursors, releasers, analogs, metabolites or combinations thereof. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 11/303,817 filed Dec. 16, 2005 which claims priority to U.S. Provisional Application Ser. No. 60/637,414 filed Dec. 18, 2005.
BACKGROUND OF THE INVENTION
[0002] The disclosed invention relates generally to the field of parallel data processing and more specifically to a system for application specific array processing and process for making same.
[0003] Most of the parallel processing of data uses two distinct models, one is a Network of Workstations (NOW) and the other is a multi-processor mainframe computer for massive numerical data processing. In the case of Network of Workstations, a software application is installed on the operating system running on these machines. The software application is responsible for receiving a set of data, usually from an outside source such as a server or other networked machine, and processes the data using the CPU. Often these software applications are designed to take advantage of free or inactive processing cycles from the CPU.
[0004] All DSP(s) and CPUs are generic processors that are specialized with software (high-level, assembly or microcode). There have been attempts to create faster processing for particular identified data, one such solution is a uniquely designed Logic Processing Unit (LPU). This LPU had a small Boolean instruction set its logic variables had only 2-bit representations (0, 1, undefined, tri-state). A novel approach, but it is still a sequential machine performing one instruction at a time and on one bit of logic at a time.
[0005] More specific types of numerical processing such as logic simulation use unique hardware to achieve the analysis. While this is effective for processing and acting on a given set of data in a time efficient manner, it does not provide the scalability presented in the architecture presented.
[0006] One of the shortcomings of current solutions is their inability to properly coordinate data. Any network of machines that employs the use of general computing resources, for example standard personal computers, has an inherent latency in the communication between processing modules. Specialized processors or networks of specialized processors often contain proprietary interconnects and interfaces, that hinders their flexibility for processing multiple types of data or interfacing to separate processing modules. Another limitation is in their ability to appropriately scale to the data presented for processing.
[0007] Even the fastest computers based on a standard CPU architecture (I.E. x86) can be classified as general purpose machines as the processors are designed to process many different types of data and are driven from any one of the many general purposes operating systems. Because these processors must be open to handle many different operations and are often architected to handle data in a serial fashion they have low efficiency for parallel processing of large data sets. While multi-core processors and technologies such as HyperThreading™ have been introduced to provide additional processing power, these technologies are still limited in that each processing core must be passed one set of data at a time and still remain ineffective for parallel processing for large sets of specific data. The architecture presented in this invention allows data to flow to one or more scaled processors specifically configured to efficiently process a given type of data when needed for processing.
[0008] A further embodiment of the invention presented describes the methods in which the Application Specific Processor architecture can be applied to the process of Boolean simulation.
[0009] Modeling of a logic design prior to committing to silicon is either done through simulation or emulation. Simulation is strictly analytical and usually done on a conventional computer. Emulation requires specialized hardware programmed with the model under test and may or may not be connected to real world (real time) devices for input and output. Isolated emulation is still considered analytical and the hardware is a simulation accelerator. When connected to the real world it is often referred to as logic validation since real world behavior can be evaluated.
[0010] Emulation and validation is very expensive but can process the model several orders of magnitude faster than simulation. Emulation hardware functions like the actual circuit which will have thousands of machines (millions of transistors) concurrently functioning. Simulation, on the other hand, is a sequential analysis of each machine in its own circuit on a one-at-a-time basis on general purpose computer hardware/software. Parallelism and concurrency are more difficult, and expensive, to accomplish with conventional computers, microcontrollers, DSP(s) or other generic hardware.
[0011] Cycle base simulators are useful for accelerating all simulations regardless of design size. At high gate counts, even cycle-based simulations on a single CPU have a severe performance penalty. Simulation designers have used a variety of techniques to create a network of machines for a single simulation. Software designed to simulate high level language representations of logic are often developed on a standard system Central Processing Unit (CPU). While this provides a ubiquitous platform for developing applications to process numerical data, simulate or other analysis, the CPU is often shared with the operating system and other applications executing. The application driving the data processing is performed in a serial fashion and has to wait for one point to be analyzed, returned, and then determine if the next set of data needs to be processed.
[0012] One method presented in this invention is to augment the CPU such that is operates on a reduced sum-of-product representation of a multi-variable logic, referred to as Logic Expression Table (LET's)
[0013] Yet another key element presented in this invention is the ability to understand and process the operational structure of logic, allowing for faster data processing when performing actions such as synthesis.
BRIEF SUMMARY OF THE INVENTION
[0014] The primary object of this invention is to provide a computational architecture for processing of data sets.
[0015] Another object of the invention is to provide data specific processing through implementation of an array of application specific processors.
[0016] Another object of the invention is to provide an extensible architecture for the parallel processing of data.
[0017] Another object of the invention is to provide a data bus capable of allowing the data to propagate to and from all available processors.
[0018] A further object of the invention is to provide a method for faster simulation of Boolean expressions.
[0019] Yet a further object of the invention is to provide a means for an application to provide data for processing.
[0020] Other objects and advantages of the present invention will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed.
[0021] In accordance with a preferred embodiment of the invention, there is disclosed a system for application specific array processing comprising: a host hardware such as a computer with operating system, a data stream controller, a computational controller, a data stream bus interface, an application specific processor, and a device driver providing a programming interface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention.
[0023] FIG. 1 is a block diagram of a computing system with the Computational Engine included.
[0024] FIG. 2 is a block diagram of the Computational Engine PCI plug-in card with logical modules.
[0025] FIG. 3 is a block diagram of the overall software architecture
[0026] FIG. 4 is a flow chart of the operations that comprise the method of the Application Specific Processors.
[0027] FIG. 5 is a diagram illustrating the Vector State Stream bus architecture.
[0028] FIG. 6 is a diagram illustrating the operation of Input and Output of individual devices from the Vector State Stream Interface.
[0029] FIG. 7 is a schematic block diagram of the Vector State Stearn hardware interface.
[0030] FIG. 8 is a flow chart of the operations that comprise the Digital Stream Bus Interface Read and Write Operations.
[0031] FIG. 9 is a block diagram of the Application Specific Processor Interface.
[0032] FIG. 10 is a flow chart of the startup and computational process.
[0033] FIG. 11 is a flow chart of a computational cycle
[0034] FIG. 12 is a diagram illustrating the Vector State Stream architecture for Boolean Simulation.
[0035] FIG. 13 is a flow chart of the operations that comprise the method of the Logic Expression Tables for Boolean Simulation.
[0036] FIG. 14 is a block diagram of the Application Specific Processor Interface configured for Boolean Simulation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] Detailed descriptions of the preferred embodiment are provided herein. It is to be understood, however, that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or manner.
[0038] This invention presents a universal method for connecting an unlimited number of processors of dissimilar types in a true data-flow manner. This method of the Vector State Stream (VSS) and its use of a Delimited Data Bus allow data to physically propagate from general memory to a processor designed for optimum processing of that data and back into general memory.
[0039] This allows the propagation of logical vectors and scalars as well as single, double and quadruple floating point numbers with equal ease among or between different mathematical or logical disciplines. As a sequential bus, there is no physical limit on how many entities may be on the bus. This in turn allows enormous arrays of mixed mode processing of data suited to this scheme. The scope of this invention becomes apparent when one considers that a large enough collection of special purpose processors can create a more general purpose environment.
[0040] Toward this end, the preferred embodiment of this invention must be application neutral physically and allow the definition of universal methods of data propagation and control. Development of application specific elements on top of these universal methods then allows mixed mode operation for very specific or broader applications.
[0041] In a preferred embodiment of this invention a conventional computer system 100 ( FIG. 1 ) is host for the PCI card referred herein as the Computational Engine 116 , which is populated with among other modules a computational controller 214 , SDRAM 210 , and an array of Application Specific Processors 220 , 222 , 224 (referred to as ASP) hardware. The Computational Engine 200 is the integrating environment for both hardware and software. The process described in this invention is known as Application Specific Array Processing (ASAP). This embodiment can have one or more conventional PCI plug-in circuit boards standard in computer platforms.
[0042] Other embodiments will house a conventional host CPU in enclosures and power supplies suitable for high-end performance. Host CPU bus standards may include standards other than PCI.
[0043] Another embodiment of this invention presents is a system and process for networked Application Specific Processors, which approach the parallelism/concurrency of emulation systems without the inherent restrictions on scalability. It will become evident from the invention description that the networking method allows dissimilar machines on the network and allows interfaces to the real world for validation. Finally, the system presented is extensible in the compiler and in the executing machines with no penalties.
[0044] The scalable array of processors is supported by a stream of data representing variables that flow from ASAP memory which is implemented using SDRAM, through all of the ASP processors memory (dual port RAM), and back into ASAP memory. An embodiment of this data stream bus will be 32-bit + control that propagates from processor to processor in a daisy chain manner. This will be conventional CMOS logic when confined to a single PCI card though can be converted to LVDS when extended to other PCI cards. Other embodiments will use larger word widths, LVDS within PCI cards and high performance LVDS or optical interconnects between PCI cards.
[0045] Low Voltage Differential Signaling (LVDS) refers to instead of having one logical bit as a 3.3 Volt signal on one pin; we have a signal as two opposite phase signals on two pins. Low voltage means instead of having 3.3 Volt swing on each pin, it is only 2.5 Volts or 1.2 Volts in current I/O standards as well as other low voltage levels in future standards. LVDS has advantages in that it is more resistant to noise and also less of a noise generator. It can run at significantly higher clock rates over longer distances.
[0046] The Data Stream Computation Controller (DSCC) 214 provides cycle-by-cycle control of data streaming from SDRAM 210 to the Data Stream Bus, supporting all defined delimiters, through the array processors 220 , 222 , 224 and back to SDRAM 210 . The DSCC controller 214 can be implemented as an Field Programmable Gate Array (FPGA) or an Application-Specific Integrated Circuit (ASIC).
[0047] One knowledgeable in the field will understand the differences between FPGA and ASIC, as the differences and engineering decisions between them are well known. In a simple implementation of the DSCC 214 it would support only the few protocols sufficient for processing first models (such as Vector State Stream protocol for simulation). More complex embodiments of this will support a multiple or a super-set of protocols that will allow simultaneous support more than one type of data processing.
[0048] The DSCC 214 also allows applications executing on the host system 100 to access the SDRAM 210 used in ASAP processing as well as direct or indirect programming and control of all of the individual processors in the ASP array. In this embodiment the DSCC 214 is a master controller and all other processing entities on the data stream bus are slaves, even if they originate data.
[0049] The Data Stream Bus Interface (DSBI) provides the interface between the data bus and the array processors. The Data Stream Bus Interface is implemented as an FPGA or ASIC, often coupled in the same processor as the DSCC 214 . The DSBI is a slave controller.
[0050] The bus disclosed in this invention is a sequential bus with delimiters intermixed with data. A delimiter defines what the next data is so that the receiving entity can respond accordingly. If the delimited is understood by the DSBI it will process bus words as 32 variables of 2-bit data. The delimiter establishes a starting address. If the leading address doesn't match a value assigned to the DSBI, it counts objects until it does.
[0051] If the delimiter is not understood by the DSBI, it ignores but passes one data to the next entity on the delimited data bus until it sees the next delimiter.
[0052] The Vector State Stream (VSS) is the actual data set that propagates on the bus and represents a complete set of data for one computational cycle. The data could be logic data for simulation or processing, but it could also be floating point data for numerical analysis, statistics, filtering or a number of other operations. In this latter case it would be termed a sample state vector. The stream property is merely the serial format the data takes in propagating on the bus.
[0053] The embodiments of the Application Specific Processor (ASP) are as varied as the number of overall applications for the whole system. Low and high-end embodiments will differ in degree of cost/performance for the same application type. Some embodiments will be unique new designs for logic. Eventually other ASPs built from new designs and/or pre-existing technology ICs (DSP(s), PIC or other processors); Verilog IP (RISC, DSP cores in FPGAs/ASICs) could and will be adapted to an ASAP process.
[0054] For logic ASPs part of the instruction of the Boolean Processing Unit (BPU) contains entries in a Logic Expression Table (LET). The LET is a table of binary numbers for N logical variables represented at 2-bit data. The table consists of I input variables and O output variables where I+0<=N. The input variable 2-bit data values “0”, “1” and “2” are defined as “0”, “I” and “don't care” respectively. The output variable 2-bit data values “0” and “1” are defined as “not included” and “included”.
[0055] Combinatorial logic can always be reduced to what is known as a Sum of Product (SOP) form. It is well known that multiple output logic in the same module, if express in SOP form, also has shared terms. The “input” side of the LET is a list of all the product terms in a given module. Any input that is not used in a product term is defined as “don't care”. Any input defined as “0” or “1” is an input to a product term in inverted or non-inverted polarity respectively. The output side of the LET is simply whether or not the input product term on the same line is included in evaluating the output.
[0056] At compile time, LET entries get included with special instructions to the BPU that efficiently match a current set of modular inputs to the input side of the LET. By this means multiple outputs get evaluated in parallel with great efficiency.
[0057] A conventional computer system ( FIG. 1 ) contains various components which support the operation of the PCI Computational Engine 116 , these components are described herein. A typical computer system 100 has a central processing until (CPU) 102 . The CPU 102 may be one of a standard microprocessor, microcontroller, digital signal processor (DSP) and similar. The present invention is not limited to the implementation of the CPU 102 . In a similar manner the memory 104 may be implemented in a variety of technologies. The memory 104 may be one of Random Access Memory (RAM), Read Only Memory (ROM), or a variant standard of RAM. For the sake of convenience, the different memory types outlined are illustrated in FIG. 1 as memory 104 . The memory 104 provides instructions and data for the processing by the CPU 102 .
[0058] System 100 also has a storage device 106 such as a hard disk for storage of operating system, program data and applications. System 100 may also include an Optical Device 108 such as a CD-ROM or DVD-ROM. System 100 also contains an Input Output Controller 110 , for supporting devices such as keyboards and cursor control devices. Other controllers usually in system 100 are the audio controller 112 for output of audio and the video controller 114 for output of display images and video data alike. The computational engine 102 is added to the system through the PCI bus 102 .
[0059] The components described above are coupled together by a bus system 118 . The bus system 118 may include a data bus, address bus, control bus, power bus, or other proprietary bus. The bus system 118 may be implemented in a variety of standards such as PCI, PCI Express, AGP and the like.
[0060] FIG. 2 shows the logical modules of the Computational Engine PCI card. For direct control the computational memory 210 , controls and status can be mapped into the PC's addressable memory space 104 .
[0000] The computational memory 210 only contains the current and next values of the computational cycle. Contiguous input data and contiguous output data would be sent to the CE from the application from a hard disk 106 , or system memory 104 . The data and delimiters what are written 206 to computational memory 210 and are managed by the application executing on the system 100 . During initialization ASP instruction and variable assignment data images are written 206 into computational memory for later transfer by the DSCC 240 .
[0061] Prior to a computational cycle, new inputs are written 206 to the computational memory 210 . The inputs may be from new real data or from a test fixture. After the computational cycle newly computed values can be read out 206 , 202 for final storage.
[0062] The application 300 can interact with the DSCC controller 240 to trigger the next computation or respond, by interrupt to the completion of the last computation or the trigger of a breakpoint of the occurrence of a fault, for example a divide by zero. In this embodiment the computational controller 240 is a specialized DMA controller with provisions for inserting certain delimiters and detecting others of its own. It is responsible for completing each step in the cycle but the cycle is really under control of the host software.
[0063] The outbound data bus 216 is new initialization or new data for processing by one of the ASP's chain. The inbound data bus 218 is computed data from the last computational cycle or status information. During initialization it also provides information on the ASP types that are a part of the overall system.
[0064] In the event that this CE is a slave to another CE its own DSCC and SDRAM become dormant and the outbound data bus is merely the outbound data coming in from the master CE. Similarly the inbound data bus to the master CE is the inbound data bus to this module.
[0065] The system can contain an inbound 226 , 230 and outbound 228 , 232 data bus option to and from a slave mode ASP CE. This allows more than one PCI card to be installed in a host system, whereby one is the primary CE and the second CE acts a slave to the primary.
[0066] FIG. 3 presents the software architecture on a host machine used to drive the DSCC 240 ASP's on the CE 200 cards. 302 is library which exposes Application Programming Interfaces (API's) for the application 300 to invoke in order to present data for analysis. 304 is the primary driver for converting the application data request to the data models needed for the CE. Using a compiler which can feed a synthesis backend we can generate a series of LET's.
[0067] The CE is initialized through the PCI interface step 400 , the ASAP process next checks the controls 402 for it's set of actions ( FIG. 4 ). The ASP is a processor in a polling loop waiting for a Go bit 404 or value to be written to either a register or a special dual-port RAM location. When it sees a Go 404 it executes code step 406 , stores the results in the SDRAM step 408 and when is get to the end of the data sets 410 it processes a done status and returns to the polling loop.
[0068] FIG. 5 is a functional diagram illustrating the Vector State Stream bus architecture. The system contains a PC host 502 with a least one PCI slot with the Computational Engine PCI card 200 plugged in. The PCI interface 504 includes hardware PCI-to-PCI bridge to isolate the host PCI bus when the lead DSCC FPGA isn't programmed. Once programmed the main DSCC memory 508 controls can be mapped into the hosts PC's memory space 104 and visa versa. The source of high level computational control from the host application 300 is through interaction with this low level DSCC 506 along with data written to and read from the SDRAM 508 . Buffer transfers to and from SDRAM 508 are through DMA channels or through I/O functions. Interaction with the DSCC controller 506 is event driven. A software monitor and Input/Output module 510 is coupled with the main DSCC controller 506 is provided for complex simulation or analysis which require high speed interaction with software that might be slower if using the SDRAM interface. The software monitor and I/O module 510 allows access to the VSS data stream by providing breakpoint and watch point functions.
[0069] A memory pool 508 is SDRAM or any other high speed DDR. This memory pool is used by the overall ASAP process. With this flexibility in the memory architecture there is no restriction on the bus size and can be hundreds of bits in width for high performance needs.
[0070] Break and watch points 512 are a mechanism to respond to select variables in the system for critical conditions or simply a meaningful change in state. The difference between the two is that a break point will halt operations, where a watch point is a method to passively monitor a variable as directed the host application 300 or active monitoring by interrupt.
[0071] The software variables in 516 and out 514 interfaces are provided such that the application 300 can feed data into or extract data from the end of a given computational cycle respectively. The real input 518 and output 540 modules provide a high-speed interface between the real world and the computational process. These interfaces are all digital and the digital numbers could be anything from basic integers to quadruple precision floating point numbers. The generic ASP 520 represented in this diagram is the basic processor type used in the majority of the computational process ( FIG. 11 ). This processor 520 is configured and used regardless whether the computational data is logic patterns, matched filters, or fast flourier transforms. The ASP's 520 are represented in FIG. 5 as derived from an FPGA pool, it is also understood that as routines data process is defined they may reside in ASIC form. The special ASP's 530 can be configured as unique to the processing application data or configured as a common machine that only provide cursory processing of data.
[0072] The VSS bus is a sequential bus and does not inherently depend on bus width or whether or it is CMOS or Low Voltage CMOS or LVDS logic levels. To simplify the diagram and facilitate understanding its function, the return path of the VSS bus is to the DSCC 506 from the Break/Watch point module 512 . A further implementation of this embodiment would have the return path is a second in-bound bus retracing back through all the modules.
[0073] The VSS bus cycles have essentially four phases of read, compute, write and optionally maintenance. Input and output devices usually won't have anything to do during the compute cycles. All devices will need to interface to this high-speed bus on the order of one bus word per clock cycle. In FPGAs the maximum internal clock speed is around 300 MHz which limits implementation at those frequencies to the simplest of structures. Gate arrays, Standard Cell and custom ASICs are operating in the neighborhoods of 500 MHz, 1 GHz and 3 GHz respectively.
[0074] FIG. 6 is a diagram illustrating the operation of input and output of individual devices from the vector state stream interface. This is a diagram further defines the scope of possible ASPs related to system input and output. Various forms of ASP can be employed to interface digital processing to real world devices. Arbitrary external logic 602 can be driving or read from arbitrary external logic with logic level translators. This form of ASP is responsible for mapping output variables in dual port RAM to output pins and input pins to variables in dual port RAM. Other logical input and output pins in this module are used as clocks or clock indicators to cleanly clock data into or out of the module with synchronization to the simulation or computational cycle.
[0075] Basic arbitrary interfaces to the analog world are indicated 604 with an Analog to Digital (A/D) and Digital to Analog (D/A) converters. Though the interface to these is a standard logic level, the I/O has some rigorous timing requirements on synthesis and sampling clocks, which must be provided by this ASPs module. This module can contain simple sampling and output generation, it can also include higher level functions of digital filter and over-sampling and produce or consume floating point rather than integer numbers.
[0076] More demanding analog I/O 606 such as video encoding and decoding involve rigorous timing standards, which aren't likely to be sustainable by computational throughput. An ASP of this type supports a time base compatible with the video standard and frame buffering so that images can be input and output at the standard rate and processing I/O is done at a rate within the computational bandwidth of this architecture.
[0077] Since the ASP can be as complex as it needs to be, there really is not any limitation on digital interfaces. The module 608 shown here is to illustrate that in addition to rigorous timing the module could handle complex protocols from physical to virtual circuit level protocols.
[0078] FIG. 7 is a schematic block diagram of the Vector State Stream hardware interface. In this diagram the device 700 is implemented as either an FPGA or ASIC which contains multiple ASP's. The input/output to the device 700 is one data stream either outbound or inbound, since at this level their behavior is identical. There are one or more clocks 702 in the system at the board level as well as the system reset to coordinate all the devices in the system. The data bus 704 can be either 16-bit, 32-bit, 64-bit and a high speed LVDS. The data field on the bus runs in parallel with the delimiter data field 706 . The delimiter field 706 is a multi-bit quantity that identifies what the data field 704 means. The transfer clocks 708 are clocks that are in phase with the output data. The use of these clocks is optional when transferring data from module to module on the same CE board since the phase of the data can be determined by the global clocks.
[0079] A flow chart of the operations that comprise the DSBI read and write operations is illustrated in FIG. 8 . The DSBI module in initiated 800 as a slave device that passes all delimiters and data is sees on the VSS to the next ASPs DSBI module. The one exception is during ASP initialization phase, address assignment delimiters detected 804 have the address field incremented 808 after current value has been loaded 806 , then the incremented value and delimiter are forwarded to the next VSS read/write 810 .
[0080] When the RAM initialization 812 delimiter is recognized the ASP address previously assigned is compared with the initialization delimiter address to select the data 814 . Some initializations are global and some are ASP specific.
[0081] After RAM initialization, the DSBI will watch 816 for delimiters to load new input variables 818 , send output variables 802 and step 822 or to start a computation 824 and step 826 to calculate output variables.
[0082] The VSS read write module 902 is a slave controller that responds to the delimiters on the VSS bus primarily to extract variables prior to calculation and splice-in or overwrite resulting variables after calculation. Administration delimiters are supported to allow the ASP's to report themselves after initialization, accept address assignment, load instructions and constants, along with any maintenance functions. The dual port RAM 904 is a block of 1 to 4 instances of Xilinx Synchronous Random Access Memory (SRAM) or an arbitrary sized block of ASIC SRAM. Each port has its own address and data bus as well as control signals and even separate clocks such that both the VSS Read/Write controller 902 and the ASP 906 can independently access any location in memory. The ASP 906 is configurable based on the data set being passed in. The ASP 906 can be a conventional processing machine with a program counter and executing instructions in the dual port RAM 904 and operating on variables in the RAM 904 . The ASP could also be configured as a mathematical processor or autonomous processor.
[0083] The configurability and the value to process unique and diverse data sets have been disclosed throughout the invention. Within the VSS bus architecture there is a provision at the processor level to bypass 908 unused ASP's in the chain of those available. For data sets that are smaller than the ASP's available, the bypass 908 is a mechanism to reduce processing time by eliminating unnecessary stages in the bus process.
[0084] In accordance with the preferred embodiment, FIG. 10 is a flow chart of the host software and its interaction with the CE board. The end user software can be a feature rich GUI application or script interfaces for running computational analysis that is outside the scope of the flowchart described herein. To simplify description this diagram includes a minimum set of operations needed for general computation, but does not limit this invention in any way. The diagram assumes a human interface that waits for a start and can accept a user break command. Obviously, these inputs would be missing in a script interface. Host software must start up and initialize itself 1000 . Software must determine 1002 what type of CE hardware has been plugged into the system. If low level CE firmware is functional, a specific CE device will enumerate itself on the PCI bus. If there is no CE hardware present 1012 , a message is generated and exits 1090 . If an all-FPGA type CE board is present 1004 , all ASPs must be programmed 1006 with a population of ASPs that will be needed for the problem at hand. All FPGA boards will be SRAM based logic programmed with block images from host files. Host software will have control over which blocks to pick for each FPGA but not any finer grain selection of ASPs within each block. If a mixed ASIC/FPGA board is present 1008 , either by looking up the ID or polling via an address assignment process, host software can determine how to program the FPGA portion for ASPs 1010 needed that are not supported in the ASICs or just adding like processors to the system. Based on the number and type of ASP present, host software will partition the processing and initialize the ASPs with code 1012 , constants and parameters and will assign variables or portions of the data set for the ASP to process.
[0085] The entire model, including test fixture 1014 , is initialized to their first values. There is a wait loop for user input 1016 . If the user generates a start 1020 , the system triggers 1022 the DSCC 240 on the CE board 200 to do one cycle. Cycle could be next Boolean vector, real time logic events, and next calculation for unit time or whatever the process needs. Next there is a decision to either poll 1024 the CE board status register for completion 1026 or wait for an interrupt. Out of the new set of data, we read out and save to disk 1028 variables identified as output. Where a display is used 1030 , we update any output variables appearing on the display. Outputs that are needed by the top-level test fixture 1032 are applied to that test fixture. 1034 new inputs from the test fixture applied to CE board. If there was a fault 1036 (divide by zero, bad vector, ASP crash, etc.) generate message 1040 and wait for new command. If there was a user initiated break 1042 in the application 300 or a user programmed breakpoint triggered, generate message 1050 and wait for new command. If the process is finished 1044 with the entire computation process, generate a message 1060 that we are done to the user and wait for a new command. Otherwise, 1046 continue the process into the next cycle.
[0086] FIG. 11 is a functional flow chart of a computational cycle. The VSS Read/Write module is a slave device on the VSS bus; the DSCC is the master device. It is a very small micro controller capable of initializing and starting DMA-like operations that take blocks of SDRAM data (at sequential addresses) and transfers them out on the VSS bus. Since DSCC operation is determined by software its operation includes, but is not limited to, the three types of operations shown here. These steps include a maintenance function (address assignment), a single step I/O process to the ASPs (ASP RAM initialization) and a multi-step computational cycle. After hardware initialization, software loads the DSCC with code and parameters needed to perform its basic operations step 1100 . DSCC monitors a register maintained by the host for a command step 1102 . If the host command is for address assignment 1104 , then the DSCC puts the address delimiter on the out-bound VSS bus with the address value field set to zero step 1106 . In step 1108 the DSCC monitors the in-bound VSS bus for detection of the address delimiter coming back from the ASPs. The delimiter's address field will contain the count of the number of ASPs in the system. Data fields following the delimiters will contain the Ids of all the ASPs in the system, which will be read into a block of SDRAM memory, which can subsequently be read by the host software.
[0087] If the host command is a block write to initialization ASP RAM 1110 the DSCC simply transfers a block of SDRAM pointed to by host software out onto the VSS bus 1112 for however many words are in the host command. In this type of block transfer, the host supplies one or more delimiters at appropriate points in the buffer. Initialization can be global (all ASPs get the same 2K of initialization) or it can be ASP specific. The DSCC is blind in this respect and is just a block transfer device. Initialization contains ASP instructions, parameters (variable assignments), and constants. Though not illustrated a block read would be similar, although one ASP at a time.
[0088] In step 1114 if the host command is to run a simulation cycle, the DSCC begins by putting out one or more blocks of current state variables onto the out-bound VSS bus until entire state is transmitted 1116 . This step operates in a similar manner to initialization in that delimiters originate from the host and all the DSCC knows is the start location and size of the current state variables.
[0089] Once the current state is transmitted, the DSCC puts out a start computation delimiter on the out-bound VSS bus, step 1118 . In step 1120 the DSCC monitors the in-bound bus for indications that all ASPs have finished their computation 1122 . In step 1124 , the DSCC sends out one or more delimiters to command the ASPs to transmit their output data. As new data come back to the DSCC on the in-bound VSS bus, the DSCC transfers the data to SDRAM by a formula established by host software in step 1126 . After the last data is read into SRAM, the DSCC signals host software with a completion flag and an interrupt in Step 1128 .
[0090] FIG. 12 is a diagram illustrating the Vector State Stream architecture for Boolean Simulation. This is a specific embodiment of the architecture outlined in FIG. 5 . In the Boolean logic simulator embodiment, is built from the same physical FPGA platform or an application specific ASIC/FPGA version. Bus protocols are such that both can be mixed in the same VSS environment. There are several application specific differences from FIG. 5 which are focused on and presented in detail below.
[0091] The VSS bus 1202 is a sequential bus and doesn't inherently depend on bus width or whether or not it is CMOS, Low Voltage CMOS, or LVDS (Low Voltage Differential Signaling) logic levels. In the Boolean embodiment data propagates on the bus in the form of words made up of two bit 2-bit data representing a logic state. A 32-bit bus contains 16-bits of logic, a 64-bit bus contains 32-bits of logic and so on. Though the return path to the computational controller is shown to be directly from the Break/Watch point module a more practical structure is that the return path is a second in-bound bus retracing back through all the modules shown. The bus was not drawn in this fashion to simplify the diagram to facilitate understanding the relevant points.
[0092] The Generic BPU (Boolean processing Unit) 1210 is responsible for executing LET (Logic Expression Tables) in dual port RAM, which are its instructions, executed in standard computational manner. Current state variables in dual port RAM are converted in the next state values by execution of LET instructions.
[0093] The Special BPUs 1220 are responsible for other forms of Boolean processing. Scalar operators such as counters, multipliers, floating point units, data selectors, address encoding/decoding, adders, sub tractors, and comparators would qualify as “special.”
[0094] FIG. 13 is a flow chart of the operations that comprise the method of the Logic Expression Tables for Boolean Simulation. The CE must first be initiated 1300 , and the first step is to check the controls 1302 . Like all ASPs the waits for a “Go” indication by polling a specific register, or a specific location in dual-port RAM, maintained by the DSBI. Once triggered 1304 , the BPU begins loading the comparator with the current state variables in the data set 1306 . LET instructions are applied against the comparator which tests the current state variables against the LET product terms 1308 . Completion of LET execution is fully deterministic and with completion all the outputs are resolved. The BPU then moves the next state variables to dual port RAM 1310 . If there are no more data sets the process set a done status 1314 and returns to the polling loop. Otherwise the BPU advances to the next data set.
[0095] Application Specific Processor can be configured for Boolean simulation FIG. 14 . This is the same illustration as provided in FIG. 9 , and provided is the description of the key differences in implementation, all other descriptions of the system remain the same. This is a Boolean simulator specific embodiment of FIG. 9 with specialized implementation. In this embodiment of the architecture the generic BPU 1402 contains a processor with a very small conventional instruction set with the addition of new instructions unique to this invention. These are mapping instructions to move input data to and from the LET comparators within the BPU and instructions to execute the LET entries (as instructions) themselves.
[0096] These LET instructions are similar in their role to conventional software in that there is fixed code that can operate on more than one set of data. It is common in logic design for there to be many replications of functional logic but connected to different data. In this architecture more than one data set (current and next state) could be assigned to the same BPU. The dual-port RAM 1404 in FIG. 9 is too non-specific to allow labeling for content without inferring restrictions. In the case of Boolean simulator embodiment this can be reduce to LET and conventional instructions for the BPU and input/output variables and possible a stack. Intermediate variables are calculated from inputs but are not output directly. They are used in subsequent operations to produce output variables and may represent shared terms in Boolean equations.
[0097] While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims. | A processing architecture and methods therein for building application specific array processing utilizing a sequential data bus for control and data propagation. The methods of array processing provided by the architecture allows for numerical analysis of large numerical data such as simulation, image processing, computer modeling or other numerical functions. The architecture is unlimited in scalability and facilitates mixed mode processing of idealized, analytical and real data, in conjunction with real time input and output. | 6 |
TECHNICAL FIELD
[0001] This disclosure relates to audio transcription.
BACKGROUND
[0002] Many systems transcribe speech to text. To improve the accuracy of each transcription a system may be trained.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 illustrates an example system for transcribing audio via re-speaking.
[0004] FIG. 2 illustrates an example system for the job mapper.
[0005] FIG. 3 illustrates an example system for the combiner module.
[0006] FIG. 4 illustrates an example process for transcribing audio via re-speaking.
DESCRIPTION OF EXAMPLE EMBODIMENTS
Overview
[0007] Some implementations may provide a computer-program product that is embedded in a non-transitory machine-readable medium and stores instructions that are executable by a processor and configured to cause the processor to perform operations for crowd sourcing audio transcription using crowd-sourcing. The operations include: receiving a speech audio intended for transcription to textual form; dividing the received speech audio into first speech segments; identifying a plurality of speakers, where a speaker is configured for repeating in spoken form a first speech segment that the speaker has listened to; determining a subset of speakers for sending each first speech segment; sending each first speech segment to the subset of speakers determined for the particular first speech segment; receiving second speech segments from the speakers, where a second speech segment is a re-spoken version of a first speech segment that has been generated by a speaker by repeating in spoken form the first speech segment that the speaker has listened to; processing the second speech segments to generate partial transcripts, where a partial transcript is a textual representation of a corresponding second speech segment; and combining the partial transcripts to generate a complete transcript that is a textual representation corresponding to the received speech audio.
DETAILED DESCRIPTION
[0008] Techniques are described for converting audio to text. A system performs this conversion by splitting the audio file into segments and sending each of the segments to number of speakers. Each speaker repeats the segment of the audio file. The system performs speech recognition on the repeated segment and combines the text of those segments to form the text of the original audio. For example, an audio file may contain the audio of a person speaking “the dog ate my homework.” The system can segment the audio file into three segments. The first segment may contain audio for “the dog.” The second segment may contain “ate my.” The third segment may contain my “homework.” The system may send the first segment to a first speaker and a second speaker, the second segment to a third speaker and a fourth speaker, and the third segment to a fifth speaker, a sixth speaker, and a seventh speaker. The system performs speech recognition on each of the segments as spoken by each of the speakers. The system may then identify possible transcripts of the first segment as “the dog,” the second segment as “ate my,” and the third segment as “homework.” Thus the system identifies a possible transcript of the entire sentence as “the dog ate my homework.”
[0009] FIG. 1 illustrates an example system 100 for transcribing audio via re-speaking. In general, the system 100 receives speech audio and outputs a final transcript of the words spoken in the speech audio. The system 100 receives speech audio at the segmenter module 110 and segments the speech audio into segments. The segmenter module 110 sends the segments to a job mapper 120 . The job mapper 120 sends the segments to speakers 130 that each re-speak a segment. Some of the speakers 130 re-speak the same segment as other speakers 130 . The system 100 sends the re-spoken segments to speech recognition units 144 . The speech recognition units 144 preform speech recognition on the re-spoken segments. The combiner module 150 receives the transcripts produced by the speech recognition units 144 and combines them into a final transcript.
[0010] The segment module 110 contains a segmenter 112 that segments the received speech audio. The segmenter 112 creates segments of the received speech audio. In some implementations, the segments each contain a word of the speech audio. For example, if the speech audio was “call me back” then the first segment would be “call,” the second segment would be “me,” and the third segment would be “back.” In some implementations, the segments each contain a particular number of words. For example, each segment may contain three words. In some implementations, the segmenter 112 segments the speech audio into a particular number of segments. For example, the segmenter 112 may divide the speech audio into five segments. In some implementations, the segmenter 112 segments the speech audio into sentence size segments. For example, the segmenter 112 may divide the speech audio into segments based on a location of natural pauses that may indicate the end of a sentence. A natural pause may be a particular period of time where there is no speech. For example, dividing the speech audio based on periods of one second where there is no speech. In some implementations, the particular period of time where there is no speech may be variable. For example, if the speech audio may contain pauses of one second, one half a second, one quarter second, and one half a second. The segment module may select the median pause length or the mean pause length and segment the speech audio based on the selected pause length such that pause lengths over or equal to the selected pause length indicate the ends or each segment. In some implementations, the segments may each be a particular length of time. For example, each segment may be ten seconds long.
[0011] The segmenter 112 stores the segments in speech segments 114 . The speech segments 114 may be any type of computer readable storage device. In some implementations, the segmenter 112 stores each speech segment with a marker. For example, the segmenter 112 may mark each speech segment with a unique marker indicating the original speech, marker indicating the speech segment number, and a marker indicating total number of speech segments from the particular speech audio. If the speech audio was “the dog ate my homework” segmented into “the dog,” “ate my,” and “homework,” then the “the dog” may contain the markers “23” to uniquely identify the source speech audio, “3” to indicate the total number of segments from the original speech audio, and “1” to indicate the segment number.
[0012] The job mapper 120 receives the segments from the speech segments 114 . The job mapper 120 identifies a group of speakers that are capable of re-speaking an audio segment. The job mapper 120 identifies a subset of the group of speakers to receive a particular audio segment and then sends the particular audio segment to the subset. Continuing the example of “the dog ate my homework,” the job mapper 120 may identify speakers 130 a , 130 b , 130 c , 130 d , 130 e , and 130 f and then determine to send the segment “ate my” to speakers 130 a , 130 b , and 130 c for re-speaking. In some implementations, the job mapper 120 may send each segment to all the identified speakers.
[0013] In some implementations, the job mapper 120 examines a user profile that is associated with the speaker and uses the user profile to determine whether to send a segment to the speaker. A user profile may indicate the sex of the speaker and the age of the speaker. In this instance, the job mapper 120 may determine to send each segment to an equal number of male and female speakers who are in various age ranges. If speaker 130 a is a twenty-five year old male, speaker 130 b is a forty-nine year old female, speaker 130 c is a 43 year old female, speaker 130 d is a sixty-six year old male, speaker 130 e is a seventy year old male, and speaker 130 f is a nineteen year old female, then the job mapper 120 may determine to send the “ate my” segment to speaker 130 a , speaker 130 b , and speaker 130 e in order to achieve a diverse group of re-speakers. Alternatively, the job mapper 120 may determine to send the “ate my” segment to speaker 130 a , speaker 130 d , and speaker 130 e if the job mapper 120 determines to send the segment to all male speakers.
[0014] In some implementations, the job mapper 120 examines information gathered from previous re-speaking jobs and uses that information to determine which segments to send to which speakers. The information may include the average time that a re-speaker takes to re-speak a segment, the gender of the speaker as detected by the system 100 , an accent of the speaker as detected by the system 100 . The job mapper 120 may determine to send the segments to speakers that re-speak the segment in under two hours. The job mapper 120 may determine to send each segment to at least three speakers who each have a different accent. The job mapper 120 may determine to send each segment to at least one speaker of each gender as the gender is determined by the system 100 .
[0015] In some implementations, the job mapper 120 examines the characteristics of each segment. The information may include the signal to noise ratio of the segment, the length of the segment, and the gender, age, and accent of the person speaking the segment. The job mapper 120 may determine to send the segments that have a signal to noise ratio below a particular threshold to more speakers. For example, the job mapper 120 may determine to send segments that have a signal to noise ratio between 5 decibels and 10 decibels to ten speakers and send segments that have a signal to noise ratio between 10 decibels and 15 decibels speakers. The job mapper may determine to send segment to speakers that are different in gender, age, and accent than the person speaking the segment. For example, if the person speaking the segment is determined by the system 100 to be a female between the age of forty and fifty with a southern United States accent, then the job mapper 120 may determine to send the segment to at least one male, at least one speaker who is about twenty years younger and a speaker who is about twenty years older, and at least person who has a slight or no accent.
[0016] The speakers 130 receive one or more segments from the job mapper to re-speak. In some implementations, the speakers 130 are people. The speakers 130 may be paid on the basis of the number of re-speaking assignments they accept and complete. The speakers 130 may be assigned re-speaking tasks by the job mapper 120 or they may select re-speaking tasks that are made available to them by the job mapper 120 . For example, a speaker 130 c may be assigned the segments “ate my” and “call” and may be responsible for re-speaking those segments. Alternatively, the job mapper 120 may make available segments “ate my” and “call” to speakers 130 a , 130 c , and 130 d and those speakers may be free to accept those segments or not.
[0017] The system 100 stores each re-spoken segment in the speech recognition module 140 . The speech recognition module 140 contains the re-spoken segments 142 . The re-spoken segments 142 are converted to text by the ASR units 144 . The re-spoken segments 142 are stored in a computer readable store device.
[0018] In some implementations, the ASR (automatic speech recognition) units 144 are unique for each speaker 130 . For example, ASR unit 144 b may perform speech recognition for speaker 130 b . In some implementations, the ASR units 144 may be trained using the respective re-spoken speech segments from the speakers 130 . For example, ASR unit 144 b may be trained using re-spoken speech segments from the speakers 130 b . Alternatively, the system 100 may contain less ASR units than the number of speakers. For example, the system may contain one hundred speakers and thirty ASR units. The system 100 may also contain only one ASR unit. In some implementations, the ASR units 144 maintains the unique identifiers added by the segmenter module 110 . Furthermore, the ASR units 144 may add data identifying the characteristics of the speakers 130 to the text of each re-spoken segment. In some implementations, different ASR units are cross-adapted. For example, the outputs of ASR unit 144 a may be used to train and adapt ASR unit 144 c.
[0019] The system 100 sends the text outputted from the ASR units 144 to the combiner module 150 . The combiner module 150 combines the text outputted form the ASR units 144 into a final transcript that represents the text of the speech audio. The combiner module 150 will be described in more detail in the discussion about FIG. 3 .
[0020] In some implementations, the system 100 includes a generic ASR module 160 . The generic ASR module 160 receives audio speech segments from the segment module 110 . The generic ASR module 160 performs speech recognition on the received segments and sends text of the segments to the combiner module 150 . In some implementations, the generic ASR module 160 is not trained based on the speakers 130 . In some implementations, the generic ASR module 160 is trained based on the received audio speech segments. In some implementations, the combiner module 150 uses the text received from the generic ASR module 160 in determining the final transcript of the speech audio.
[0021] FIG. 2 illustrates an example system for the job mapper 200 . In general, the job mapper 200 receives segmented speech audio from the segmenter and determines the speakers that should receive each segment of speech audio and sends the segments to the speakers. The speech segment character examiner 202 receives the segments and identifies the characteristics of each segment. The speech segment character examiner 202 sends the segment and the identified characteristics to the speech segment speaker mapper 208 . The speech segment speaker mapper 208 receives data from the speech segment characteristic examiner 202 , the speaker profiles 204 and the collected jobs data 206 . The speaker profiles 204 contains data received from the speakers about the speakers. The collected jobs data 206 contains data that the system collected regarding the speakers. The speech segment speaker mapper 208 uses the information received to send each segment to the appropriate speakers.
[0022] The speech segment character examiner 202 receives segments from the segmenter and identifies characteristics of each segment. The speech segment character examiner 202 may determine the signal to noise ratio of each segment as well as other audio metrics such as sampling rate. The speech segment character examiner 202 may also attempt to identify the gender, age range, and accent of the segment speaker. The speech segment character examiner 202 can attach these characteristics to the speech segment. The age range may be in ten year ranges. For example, the speech segment character examiner 202 may identify a segment speaker at between 20 and 29. The accent may be selected from a group of accents that the speech segment character examiner 202 is able to identify.
[0023] The speaker profiles 204 contains data related to the profiles provided by the speakers. The speakers may provide their gender, age, native language, date of birth, or any other relevant information. The speaker profiles 204 may be contained in a database such that the system 100 can access all speakers with an age of 60 or who have a native language of Spanish or who are between 25 and 34 and whose native language is English. The speaker profiles 204 may also contain data related to which speakers are currently performing re-speaking jobs and which ones may not be performing re-speaking jobs. Furthermore, the speaker profiles 204 may contain data related to how many re-speaking jobs the speakers wish to perform in a given period of time. For example, the speaker profiles 204 may indicate that a particular speaker wishes to perform about fifty re-speaking jobs in a week.
[0024] The collected jobs data 206 contains data collected by the system when the speakers perform a re-speaking jobs. The collected jobs data 206 may contain data such as the average time that a speaker takes to perform a re-speaking job, any data associated with the gender of the speaker, any data related to an accent of the speaker, and any data related to a perceived age of the speaker. The collected jobs data 206 may also contain data related to the performance of each speaker. For example, if the audio segment was “dog ate” and the system or a person reviewing the re-spoken audio determines that the speaker said “cat drank” then that would be noted in the collected jobs data 206 . The collected jobs data 206 may contain the total number of re-speaking jobs performed by each speaker and the average number of re-speaking jobs performed in a particular period of time. For example, the collected jobs data 206 may indicate that a speaker has performed 284 total re-speaking jobs and averaged twenty-three completed re-speaking jobs per week. The collected jobs data 206 may also contain data indicating the number of re-speaking jobs pending for each speaker. For example, if a speaker has accepted and not completed four re-speaking jobs, then that data will be noted. Additionally, if the system has assigned one or more re-speaking jobs, then that data will be noted.
[0025] The data from the speech segment characteristic examiner 202 , the speaker profiles 204 , and the collected jobs data 206 is compiled by the speech segment speaker mapper 208 . The speech segment speaker mapper 208 uses the compiled data to determine which speakers to send each segment to. In some implementations, the speech segment speaker mapper 208 may send each segment to all the available speakers. In some implementations, the speech segment speaker mapper 208 may use the complied data to send each segment to a diverse group of speakers. In some implementations, the speech segment speaker mapper 208 may send each segment to a specific number of speakers. In some implementations, the speech segment speaker mapper 208 may send each speech segment to a speakers that complete the re-speaking job within a particular period of time. In some implementations, the speech segment speaker mapper 208 may select more speakers than needed for each segment and wait until the needed number accepts before withdrawing the segment. For example, the speech segment speaker mapper 208 may determine that four speakers should re-speak “ate my.” The speech segment speaker mapper 208 may select ten potential speakers that fit the desired profile for speakers. The speech segment speaker mapper 208 will wait until four speakers have accepted the re-speaking job, then no longer offer that job to the other six speakers. The speech segment speaker mapper 208 may use any combination of these when selecting speakers for each segment.
[0026] FIG. 3 illustrates an example system for the combiner module 300 . The combiner module 300 receives text of the segments from the ASR units. The text of the segments are stored in the partial transcripts 302 . The combiner module 300 uses the container algorithms 304 and a voting mechanism 306 to determine the final transcripts 308 that represent the original speech audio.
[0027] The system utilizes the container algorithms 304 to arrange each segment into container form. The container contains all instances of recognition output for a given speech segment. The voting mechanism 306 selects portions of the segments from the arrangement of the segments and combines the segments into the final transcript for that segment. Finally, the system combines the various final segment transcripts to create the final transcript for the original speech audio. In some implementations, the portions of the segments are based on words. For example, if the segment from one of the ASR units is “ate my homework,” then each partial segment based on words would be “ate,” “my,” and “homework.” In some implementations, the voting mechanism 306 is performed on a per-word basis. The voting mechanism 306 may select the transcript that is the most popular among the speakers. For example, if the transcript for one of the partial segments from each of the speakers was “ate,” “ate,” “ape,” “quaint,” and “ate,” then the voting mechanism 306 would select “ate” as the final transcript for that partial segment.
[0028] In some implementations, the container algorithms 304 contains the ROVER algorithm. In the ROVER algorithm, the first-best output of an individual ASR unit is used. The ROVER algorithm uses a word by word voting scheme to determine the individual final partial segment transcripts. Thus, if “ate” is the most popular transcript for a particular word from the speech audio, then the ROVER algorithm would select that word. Alternatively, the ROVER algorithm can vote using interpolation of word confidences. The system then combines the word-by-word final partial segments to create the final segment transcript. In some implementations, the container algorithms 304 contains confusion network combination. In the confusion network combination algorithm, the first best hypotheses or first best outputs are replaced by individual confusion networks for each ASR unit. In some implementations, the container algorithms 304 contains word lattices. The system combines word lattices and derives a confusion network based on the word lattices. In this instance, the first best hypothesis becomes the ASR unit output. In some implementations, confusion networks are not used. Instead, minimum Bayes risk decoding on the combined lattices may be used. In some implementations, the ASR units' models are combined in a log-linear manner to decode the first best path in, for example, the word lattice that was constructed by combining the individual ASR units' word lattices. The voting mechanism 306 selects the most likely transcript and outputs the final segment transcript. Finally, the different final segment transcripts are put together to form the final transcript 308 .
[0029] FIG. 4 illustrates an example process 400 for transcribing audio via re-speaking. In general, the process 400 determines a transcript for speech audio by segmenting the speech audio and sending each segment to one or more speakers for re-speaking. The re-spoken segments are transcribed by an ASR unit paired with each speaker. The transcripts are then combined to form a final transcript. The process 400 will be described as being performed by a computer system comprising one or more computers, for example, the system 100 as shown in FIG. 1 .
[0030] The system receives speech audio for transcription to textual form ( 402 ). The speech audio may be an audio file of any length and compressed using any algorithm that the system is capable of decoding. The system divides speech audio into first speech segments ( 404 ). In some implementations, the system divides the speech audio based on time. For example, the system may divide the speech audio into one minute segments. In some implementations, the system divides the speech audio up into segments of a particular number of words. For example, the system may divide the speech audio into fifty word segments. The system may count words based upon short areas of silence that are typically between words.
[0031] The system identifies speakers who are configured for repeating speech segments ( 406 ). The identified speakers may be those speakers who are willing to and available for repeating speech segments. The system determines a subset of speakers for each first speech segment ( 408 ). The system may determine the subset of speakers based on a profile of the speakers. The profile of the speakers may contain details about the speaker and is submitted by the speaker. The system may determine the subset of speakers based on data collected about the speakers from previous repeating jobs. The collected data may be related to the performance of the speakers, any perceived characteristics of the speakers, such as accent, gender, and age, any completion time data related to previous repeating jobs. The system may determine the subset of speakers based on the characteristics of the speech audio. The system may use the signal to noise ration of the speech audio or the signal to noise ratio of each segment when determining a subset of speakers. The system may also use the perceived age, gender, or accent of the speaker when determining a subset of speakers. The system may determine a subset of speakers to achieve a diverse group of speakers to repeat the segments.
[0032] The system sends each first speech segment to a respective subset of speakers ( 410 ). The respective subset of speakers repeats the respective first speech segment. The system receives second speech segments from the speakers ( 412 ). The second speech segments are segments that the speakers repeat. The system processes the second speech segments to generate partial transcripts ( 414 ). The system may have an ASR unit for each of the speakers and those ASR units may be trained by data from the respective speaker. Alternatively, the system may have fewer ASR units than speakers. In some implementations, there may be a particular number of speakers for one ASR unit. In some implementations, there may be a particular number of ASR units that process repeated segments from the speakers selected by the system.
[0033] The system combines the partial transcripts to generate a complete transcript for the received speech audio ( 416 ). The system combines the partial transcripts for each segment to determine the most likely transcription for the segment and combines the most likely transcriptions into a complete transcript. The system may arrange the partial transcripts into a container form and select portions of the partial transcripts from the container form using a voting mechanism. In some implementations, the portions may be based on a word and the voting mechanism may be performed on a per-word basis. In some implementations, the container form may be an n-best list, a word lattice, or a confusion network combination.
[0034] Embodiments of the subject matter and the operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them. Embodiments of the subject matter described in this specification can be implemented as one or more computer programs, i.e., one or more modules of computer program instructions, encoded on computer storage medium for execution by, or to control the operation of, data processing apparatus. Alternatively or in addition, the program instructions can be encoded on an artificially-generated propagated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal, that is generated to encode information for transmission to suitable receiver apparatus for execution by a data processing apparatus. A computer storage medium can be, or be included in, a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of one or more of them. Moreover, while a computer storage medium is not a propagated signal, a computer storage medium can be a source or destination of computer program instructions encoded in an artificially-generated propagated signal. The computer storage medium can also be, or be included in, one or more separate physical components or media (e.g., multiple CDs, disks, or other storage devices).
[0035] The operations described in this specification can be implemented as operations performed by a data processing apparatus on data stored on one or more computer-readable storage devices or received from other sources.
[0036] The term “data processing apparatus” encompasses all kinds of apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, a system on a chip, or multiple ones, or combinations, of the foregoing The apparatus can include special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit). The apparatus can also include, in addition to hardware, code that creates an execution environment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, a cross-platform runtime environment, a virtual machine, or a combination of one or more of them. The apparatus and execution environment can realize various different computing model infrastructures, such as web services, distributed computing and grid computing infrastructures.
[0037] A computer program (also known as a program, software, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, declarative or procedural languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, object, or other unit suitable for use in a computing environment. A computer program may, but need not, correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub-programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network.
[0038] The processes and logic flows described in this specification can be performed by one or more programmable processors executing one or more computer programs to perform actions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit).
[0039] Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The essential elements of a computer are a processor for performing actions in accordance with instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto-optical disks, or optical disks. However, a computer need not have such devices. Moreover, a computer can be embedded in another device, e.g., a mobile telephone, a personal digital assistant (PDA), a mobile audio or video player, a game console, a Global Positioning System (GPS) receiver, or a portable storage device (e.g., a universal serial bus (USB) flash drive), to name just a few. Devices suitable for storing computer program instructions and data include all forms of non-volatile memory, media and memory devices, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.
[0040] To provide for interaction with a user, embodiments of the subject matter described in this specification can be implemented on a computer having a display device, e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user and a keyboard and a pointing device, e.g., a mouse or a trackball, by which the user can provide input to the computer. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including acoustic, speech, or tactile input. In addition, a computer can interact with a user by sending documents to and receiving documents from a device that is used by the user; for example, by sending web pages to a web browser on a user's client device in response to requests received from the web browser.
[0041] Embodiments of the subject matter described in this specification can be implemented in a computing system that includes a back-end component, e.g., as a data server, or that includes a middleware component, e.g., an application server, or that includes a front-end component, e.g., a client computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the subject matter described in this specification, or any combination of one or more such back-end, middleware, or front-end components. The components of the system can be interconnected by any form or medium of digital data communication, e.g., a communication network. Examples of communication networks include a local area network (“LAN”) and a wide area network (“WAN”), an inter-network (e.g., the Internet), and peer-to-peer networks (e.g., ad hoc peer-to-peer networks).
[0042] A system of one or more computers can be configured to perform particular operations or actions by virtue of having software, firmware, hardware, or a combination of them installed on the system that in operation causes or cause the system to perform the actions. One or more computer programs can be configured to perform particular operations or actions by virtue of including instructions that, when executed by data processing apparatus, cause the apparatus to perform the actions.
[0043] The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. In some embodiments, a server transmits data (e.g., an HTML page) to a client device (e.g., for purposes of displaying data to and receiving user input from a user interacting with the client device). Data generated at the client device (e.g., a result of the user interaction) can be received from the client device at the server.
[0044] While this specification contains many specific implementation details, these should not be construed as limitations on the scope of any inventions or of what may be claimed, but rather as descriptions of features specific to particular embodiments of particular inventions. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.
[0045] Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the embodiments described above should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.
[0046] Thus, particular embodiments of the subject matter have been described. Other embodiments are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In certain implementations, multitasking and parallel processing may be advantageous. | Speech audio that is intended for transcription into textual form is received. The received speech audio is divided into first speech segments. A plurality of speakers is identified. A speaker is configured for repeating in spoken form a first speech segment that the speaker has listened to. A subset of speakers is determined for sending each first speech segment. Each first speech segment is sent to the subset of speakers determined for the particular first speech segment. The second speech segments are received from the speakers. The second speech segment is a re-spoken version of a first speech segment that has been generated by a speaker by repeating in spoken form the first speech segment. The second speech segments are processed to generate partial transcripts. The partial transcripts are combined to generate a complete transcript that is a textual representation corresponding to the received speech audio. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to a fast gamma correction method for image reading apparatus, especially to a fast gamma correction method for image reading apparatus with less storage space.
BACKGROUND OF THE INVENTION
[0002] The image reading apparatus such as scanner, digital still camera and video camera become popular, as the Internet is prevalent. The image reading apparatus have different mechanism and physical property with image output apparatus such as display and printer. Therefore, the image data obtained from the image reading apparatus generally requires correction such as gamma correction to present picture with fidelity.
[0003] Provided that X denotes input pixel data and Y denotes output pixel data, the Gamma correction can be expressed in the form Y=X γ , or other empirical curve. The function representation is hard to realize by hardware, look-up table is often used to enhance processing speed. The size of the gamma correction table depends on the resolution (bit number) of the input pixel data and output pixel data. The gamma correction table requires 4K word storage space of 12-bit input data and 8-bit output data. The gamma correction table requires 64K word storage space of 16-bit input data and 8-bit output data, which is not feasible for ordinary platform.
[0004] The applicability of the look-up table is also limited by data accessing speed. The page mode accessing is not useful due to the randomness of pixel data. The data accessing time is 120 ns for external 60 ns DRAM.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to provide a gamma correction method for image reading apparatus with less storage space.
[0006] It is an object of the present invention to provide a gamma correction method for image reading apparatus with fast accessing speed.
[0007] To achieve above objects, the gamma correction method for image reading apparatus according to the present invention comprises following steps:
[0008] a. provided that the normalized output pixel data Y is quantified by n-bit, the original 2 n intervals is reduced to M merged interval, wherein M≦2 n , the original correction function is represent by an approximated function with simple function form in each merged interval;
[0009] b. reading normalized input pixel data X and allocating the read data to a merged interval;
[0010] c. finding the normalized output pixel data Y by approximated function in the merged interval and the normalized input pixel data X.
[0011] The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing, in which:
BRIEF DESCRIPTION OF DRAWING
[0012] [0012]FIG. 1 is an example with liner fitting function for gamma correction function;
[0013] [0013]FIG. 2 demonstrates interval mergence in the present invention;
[0014] [0014]FIG. 3 shows a block diagram to realize the gamma correction method according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] The gamma correction function is generally monotonic function, therefore, realistic gamma correction function can be approximated by a simple function such as linear function or polynomial function is a specific interval. The gamma correction function has good approximation by prudently choosing interval and approximating function even though the gamma correction function is not monotonic function.
[0016] [0016]FIG. 1 shows a first example of gamma correction function approximated by a linear function, wherein X denotes normalized input signal to be corrected and Y denotes normalized output signal to be corrected. The normalized output signal Y is quantified to 2 bit for illustration. The threshold values of Y coordinate are 0, 0.25, 0.5, 0.75, and 1. That is, the output between 0 and 0.25 is corresponding to Y 1 (code 00), the output between 0.25 and 0.5 is corresponding to Y 2 (code 01, etc. The solid line in this figure represents realistic gamma correction function and the dashed line in this figure represents approximated gamma correction function. The threshold values of X coordinate X T0 , X T1 , X T2 , X T3 , X T4 can be obtained by inversely mapping threshold values of Y coordinate 0, 0.25, 0.5, 0.75, 1 with respect to realistic gamma correction function.
[0017] In the example shown in FIG. 1, the related interval of the input pixel data X is determined with reference to the threshold values of X coordinate X T0 , X T1 , X T2 , X T3 , X T4 and then an appropriate fitting function is used to obtain corresponding output pixel data Y. In the example shown in FIG. 1, two comparison steps are required if binary search is used. If the output pixel data Y is represented by n-bit, n times of comparison is required, which is time consuming. In the present invention, the 2 n intervals are merged to reduce search time.
[0018] The symbols used in the specification are list below for clarity:
[0019] m: resolution of input data
[0020] n: resolution of output data
[0021] {Y 0 , Y 1 . . . Y 2 n −1 }: symbolic set of output data
[0022] {X 0 , X 1 . . . X 2 m −1 }: symbolic set of input data
[0023] {T 0 , T 1 . . . T 2 n }: threshold set
[0024] Y=G(X): realistic color correction function
[0025] F (h,k) (.) fitting function in interval (T h , T k )
[0026] D(.): distortion measure function
[0027] Q(.): quantizer function
[0028] Provided T 0 =0, T 2 n =1, which are boundary values of output pixel data and the thresholds T 0 , T 1 . . . T 2 n divide the range of normalized output data into 2 n intervals. The normalized output data can be obtained with reference to the thresholds Y j =(T j +T j+1 )/2,j=0, 1, 2 . . . 2 n −1 and the quantization of normalized output data is executed by following formula:
Q ( Y )=min{ D ( Y−Y j )| Y j , j= 0˜2 n −1}
[0029] The input thresholds can also be obtained by the output thresholds:
{G −1 ( T 0 ),G −1 ( T 1 ) . . . G −1 ( T 2 n )}
[0030] If the 2n intervals are not merged, the related interval of the input data is found and then the output signal is obtained by the function relationship Y=G(X). For example, for the input data G −1 (T j )<X<G −1 (T J+1 ), the output signal corresponding to X is Y j .
[0031] The present invention is characterized in that the 2 n intervals of the output data are merged into a plurality of merged intervals, and the color correction function in each merged interval can be approximated by a suitable fitting function. For example, if the intervals between T h to T k are combined to a merged interval and the color correction function in the merged interval is approximated by a fitting function F (h,k) (.), which is a simple function such as a linear function or exponential function.
[0032] [0032]FIG. 2 demonstrates interval mergence in the present invention, wherein the fitting function F (h,k) is a linear function represented by dashed line and the realistic color correction function is represented by solid line. In this example, m=3 and n=2, and there are four intervals for the output data. When one tries to combine interval (T 2 , T 3 ) and (T 3 ,T 4 ), and approximates the color correction function in the merged interval by a fitting function F (2,4) (.). The quantized input data X 4 has contradiction because Q(F (2,4) (X 4 ))=Y 2 and Q(G (X 4 ))=Y 3. Therefore, the interval (T 2 , T 3 ) and (T 3 ,T 4 ) cannot be combined. On the contrary, the combination of intervals (T 0 , T 1 ) and (T 1 ,T 2 ) are safe. Therefore, the intervals (T 0 , T 1 ) and (T 1 ,T 2 ) can be combined into a merged (T 0 , T 2 ), and the color correction function in the merged interval is approximated by a fitting function F (0,2) (.).
[0033] Hereinafter is the merging algorithm for intervals
[0034] step 0: set k=0;
[0035] step 1: set h=k;
[0036] step 2: set=k+1;
[0037] step 3: if k=2 n , stop;
[0038] step 4: if s is within (h,k), and all X T , T=0 . . . 2 m −1, in (G −1 (T s ), G −1 (T s+1 )), are equal to all X T , T=0 . . . 2 m −1 in (F 1 (h,k) (T s ), F 1 (h,k) (T s+1 )), back to step 2;
[0039] step 5: merging (T h , T h+1 )˜(T k−1 , T k ) into (T h , T k ), and recoding F (h,k) (.);
[0040] step 6: back to step 1.
[0041] As can be seen from above algorithm, the criterion to validate the merged interval is to check the consistence between the input data obtained by inverse mapping all output data in the merged interval by realistic color correction function and the input data obtained by inverse mapping all output data in the merged interval by fitting function. If the validation is positive, the mergence is allowable and next interval to the merged interval is tested for further mergence.
[0042] [0042]FIG. 3 shows a block diagram to realize the gamma correction method according to the present invention, wherein X denotes the normalized data to be corrected and Y denotes the normalized data after correction. The block diagram comprises a searching unit 102 , a storage unit 104 and a curve fitting and output mapping unit 106 . The searching unit 102 is used to found the related interval for the normalized input data X. The storage unit 104 is used to store the merged interval (X j , X j+1 ), j=0 . . . M−1. The curve fitting and output mapping unit 106 is used to generate a fitting function corresponding to a related interval and then maps the input data to a corresponding corrected output data. For an input normalized data X to be corrected, the searching unit 102 compares the input normalized data X with thresholds in the storage unit 104 and finds a related interval for the input normalized data X. The curve fitting and output mapping unit 106 generates a fitting function corresponding to the related interval and then maps the input data to a corresponding corrected output data. Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have suggested in the foregoing description, and other 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 fast gamma correction method for image reading apparatus is proposed. The original intervals for normalized output data are combined to merged interval with less number and the original color correction function is replaced by a fitting function in the merged interval. For an input normalized data, the corresponding merged interval is found and a fitting function associated with the merged interval is invoked to find the corresponding normalized and corrected data. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The subject application is a continuation of U.S. application Ser. No. 12/798,803, filed Apr. 12, 2010, which claims the benefit of U.S. Provisional Application No. 61/168,838, filed Apr. 13, 2009, which applications are incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to automated vending machines. More particularly, the present invention relates to smart, computer controlled interactive vending machines equipped with a method and system for capturing and retaining consumer information and for authenticating returning consumers in conjunction with automated retail and or interactive retail deployments and retail displays.
[0004] 2. Description of the Related Art
[0005] Numerous prior art vending machines exist for selling or vending diverse products through an automated, or ‘self-service’ format. Vending reached popularity in the late 1800's with coin-operated devices dispensing diverse merchandise. More recently vending machines have evolved to include robotic dispensing components, and/or PCs and virtual interfaces. These new vending platforms have emerged m the marketplace under the popular descriptions “automated retail,” “interactive retail,” and/or “interactive retail displays.” Such vending machines may be deployed within a variety of retail or commercial settings. They typically include illuminated, visual displays that seek to attract and educate customers or potential customers. Product information may be customer-requested utilizing interactive displays, including touch screen computer interfaces and virtual interfaces.
[0006] Current automated retail units are assembled as single integrated, or stand-alone store units with merchandising displays and mechanical components integrated into a single platform. Typical platforms provide an interface with a single touch screen with limited peripherals (such as a keyboard). This makes entering complex data (usernames, passwords, addresses, preference information) difficult. Usually only minimal customer data is inputted to initiate a vend. Historically, vending and automated retail, machines do not have a viable method or process for associating specific repeat customers to previous sales, preferences and reward programs, m part because of the lack of properly accumulated and inventoried customer data. Customer profiling has not been emphasized in the vending arts.
[0007] Unlike normal stores, staffed with experienced sales people that often recognize and greet repeat customers accordingly, vending machines can be quite impersonal. Successful sales people know certain things that a repeat customer likes or dislikes. Store personnel understand customer personalities, so they can recommend various items. Sales personnel can recommend products that a customer might want to try, based upon that customers' past performance. Thus in normal retail outlets, experienced sales personnel, armed with information concerning the habits and preferences of repeat customers, provide superior services and benefits to customers, while enhancing store goodwill and maximizing establishment revenue.
[0008] Self-service, automated vending machines can no doubt benefit by emulating the “personal touch” normally provided by human interaction in typical retail stores. We have determined that there is a value in having an easy-to-use customer retention program in a self-service vending unit, that familiarizes the vending unit with the likes and dislikes of repeat customers, based upon information gleaned from past customer interactions.
[0009] Product suppliers want to connect to their customer base. Brand-preferences are strong with some customers. In the prior art there is no easy way for customers to currently indicate their interest in a given brand at the time of purchase, and to communicate their contact information. This is usually done afterwards through product registrations via postal mail. Sign up processes online are difficult, requiring multiple steps that are time consuming.
[0010] It is thus desirable to provide a method and system for customer retention that is efficient and easy to use in a self-service machine such as automated retail store, retail kiosk, interactive digital signage system, etc. It is further desirable for such a system to use a variety of personally identifiable information to authenticate a user on a self-service machine to provide access to member benefits and privileges. It is also desirable to limit abuse of those benefits and privileges.
BRIEF SUMMARY OF THE INVENTION
[0011] This invention provides an improved method for users of a self-service vending system to establish and manage a customer profile, and to become part of a membership program that gives them instant access to rewards, discounts and free products.
[0012] Data may be inputted through a magnetic card reader, RFID reader, at Bluetooth receiving unit that reads personal identifying information. Peripheral input devices such as touch screens and/or keypads may input information as well. The software utilizes a centralized database connected via a wireless or wired connection that stores inputted customer data for later use at any one of numerous, connected self-service stations.
[0013] A software algorithm generates a global unique identifier (GUID) for individual customers that uniquely identifies the user across all machines and platforms. The GUID is derived from personally identifiable information such as part of a credit card number, a non-identifying calculated number based off that number, a user's name, or an email address. An advantage is that, while the GUID is uniquely derived in part from personal information, it contains no identifiable personal information. By design, information such as a user profile and buying habits can be attached to the GUID. The system allows for a multitude of identifying options the user may select each is globally unique. This means that the pieces that make up the identifying information are structured in a way that there are no duplicates and that a user can properly restrict this access in a secure way.
[0014] For example, a unique combination can result from a portion of information taken from a user's credit card that can be combined with an email address. The email address is unique because of general domain and internet system requirements. A credit card provides security in that a person must be in possession of it to access the system. These two pieces of information used in concert provide an adequately secure way to access the system. Another possible combination could be a cell phone number and a personal identification number (PIN) selected by the user. The cell phone number provides a globally unique item and the PIN provides a level of security. A fingerprint is considered unique and secure. The system can however can pair a fingerprint scan with a pass phrase to compensate for any limitations in the technology to read a unique fingerprint. The system can also use its built-in camera for facial recognition. Because of limitations in technology and the naturally occurring phenomenon of identical twins, this facial recognition can also be paired with a PIN or pass phrase. The system can also read the Media Access Control address (MAC address) front wifeless enabled devices. The MAC addresses are designed to be unique, but because they can be altered by users, this MAC address is paired with a PIN or pass phrase to make it both unique and secure. The system can be altered at any time to add additional methods of unique and secure identification, but the process remains the same.
[0015] The multiple authentication options of the preferred invention allows for a superior consumer experience. Consumers can associate different methods of identifying themselves to a registered account. This invention offers several advantages. One advantage is that users can easily sign up with minimal manual input. Another advantage is that a user can choose the method that suits their individual preferences. Users also have multiple options of identifying with a machine in case they forgot one of their identification methods.
[0016] The connection of all machines on a network to a centralized data repository and system allows a fluid consumer experience across multiple automated retail stores or digital signage environments. This is a great advantage as a user's preferences are acknowledged at any location where they identify themselves with their registered account. One advantage is that the user's buying preferences are recognised during their user session. These may include options to quickly purchase frequently bought items, the highlighting of categories of products that are of interest and the de-emphasis of products and items are of little interest to the user. Another advantage is the recommendation or special product offers on products that may interest the user based on current usage, previous purchases or historical usage patterns. Users may also accumulate various status levels based on their patronage. Each time a user identities themselves on a machine and purchases merchandise or samples or tries qualifying items, they receive points that are associated with their account. These points may be traded in for merchandise, discounts or other benefits as determined by administrative marketing personnel.
[0017] The preferred invention provides a system and mechanism to prevent the abuse of a free sample dispensing program. In an automated machine, it is important to control the free distribution of any product or item. The invention makes the membership registration process compulsory, requiring any user requesting a sample to be an existing registered user or sign up to become one. The membership process uses items that are globally unique, and the majority of users would rarely have more than one. Examples of these could include but are not limited to cell phone numbers, credit cards, MAC addresses on wireless devices. Because of this, it is difficult for a single user to register more than once. Samples are entered into the data system using a unique product identifier in the system. Each sample type is associated with a full sized retail version of the product that is also identified in the system using a unique identifier. Each time a sample is dispensed, the user id, sample id, date and dispense location are logged in a data file that is centrally stored and retrievable by any machine connected to the system. Once a user is registered, sample deliver can be controlled to a given rule set. Some implemented rules may include but are not limited to only sample type per registered user and only one sample a day per registered user. Sample id type, registered user and the date are logged during sample dispensing so product purchases by registered users who identify themselves on the system can be tracked linking purchases to giveaways. These numbers can be analyzed to determine marketing effectiveness by an automated routine or by a manual process.
[0018] Another advantage of the preferred system is that the advanced recording and logging of user actions can be associated with a specific user to enhance the consumer's experience. Motion sensors and touch sensors mounted in the machine can sense various user interactions with the machine. Each of these events are recorded and logged by the system. When a registered user identifies themselves on a machine, the interactions can be associated with a specific user. This information can be correlated in real time or after a user's session, to enhance the consumer experience. The information used can be a collection of a registered user's entire interaction history, sub segments of that history, or it can be based on current actions. Examples of an enhanced user experience include:
a) broadcast promotions and sales to the registered user's contact information based on a collection of aggregated data of the user's actions over a period of time. b) up-sell or cross sell products that are related to the products, items or brands in which the user showed interest based on the recorded actions c) group frequent or repeat purchase items into a custom easy to select button on the touch screen so a user can quickly purchase the items they want. d) provide on screen product recommendations based on what products or brands were viewed, selected, added to the list for purchase and purchased. e) display videos, text messages, image messages on the touch screen or through the audio system providing more information on products, brands and items in which the user has shown an interest through a collection of their actions over a period of time.
[0024] The preferred invention also allows users to communicate with other contacts not registered on the system, or to communicate directly with other registered users of the system. Examples of enhanced user options include the ability to:
a) send a cell phone text message (SMS), an email or other electronic communication message to another person containing a product, item or brand recommendation directly from the machine by entering in the contact information of the other person. If the contact information matches the contact information of another registered user, the current user will also be provided the option to message the user on the local system. In this case, a message would be presented to the user when they use any machine or log into the linked website. b) post a recommendation, viewing action, or purchase action on a machine to a website, social networking website, news feed, message board or any other election posting system by linking their member registration to their external account that gives them the proper permissions to post. c) purchase a gift for another person and send them a message on how to receive the product. The message will contain a code that a user can enter into any machine that will present the gift which may be a credit amount redeemable for selected merchandise in the machine or a specific product or group of products subject to availability.
[0028] Preferably, the process is initiated when a user selects a membership digital button on the touch screen, or attempts to exercise a membership privilege, such as receiving a free product sample. The user is then prompted for some identifying information that will uniquely identify the consumer as a returning user. These could be any of the following: a credit card, an ID card with an encoded magnetic stripe, a cell phone number, a wireless device with a unique Media Access Control (MAC) address, facial recognition scan, fingerprint scan or any other mechanism that is proven to be unique and identifiable to one person as previously described. Depending on the mechanism, an additional information point such as a password, pass phrase or personal identification number (PIN) may be used in combination with the unique element to ensure it is securely linked to the correct registered user. This step further minimizes the risk of fraudulent attempts.
[0029] The invention consists of a series of merchandise display, promotional/digital signage, automated mechanical/dispensing, and/or transactional modules that can be assembled and configured to create an automated retail store, or interactive retail display of any size and link together via an virtual integrated network.
[0030] The invention also allows for a user to register on any machine and access their information, receive member benefits on any other machine on the network. All member activity can be tracked across every machine deployed on the network and in real-time regardless of where the user originally registered. In addition, membership restrictions can be imposed and enforced system wide.
[0031] Thus a basic object of our invention is to provide a more effective consumer retail experience on an automated vending machine or interactive retail display.
[0032] Another important object is to provide an interactive retail display in the form of a vending machine that uses interactive lighting and produces variable lighting effects in response to user inputs.
[0033] Other objects are as follows:
a) to provide a system that can easily and cost effectively allow users of a kiosk, vending unit, automated retail store, digital signage unit, POS system or similar self service system to sign up for membership or ‘club’ program using an identifying card (e.g. credit card, license, magnetic or RFID card, etc.) and a user interface to identify themselves and sign up and be recognized as a returning user. b) to provide a method of which users can “register” and/or “sign up” for a membership program on an automated kiosk. c) to provide a method for which member users can get instant access to product samples. d) to provide a method for which member users can get discounts. e) to provide a method for which member users can accumulate “points” or “credits” for purchases made that can be applied to benefits such as discounts, free products or other offerings. f) to provide a method for which members can select and/or connect to brand partners in which they are interested. g) to provide a method for storing member selections including preferred brands, or products in a database that can be accessed remotely or referenced in during the member's interaction with the kiosk to enhance consumer experience through product recommendations, user presentation and/or specials/deals. h) to provide a method for which various means of personal identification such as an identifying magnetic stripe card (credit card, license, government id, membership id card, etc.), RFID device (cell phone, smart card, mobile device), Bluetooth enabled device (cell phone, mobile device, etc.) or infrared signaling device (cell phone, mobile device, etc.) can be used to sign up for/register and later be used to he recognized when returning. i) to provide a method for tracking user behavior in a kiosk and leveraging behavior tracking to cross-sell, up-sell and deepen with the consumer. j) to provide a method that allows a registered user's actions to be logged and recorded. k) to provide a method that allows a registered user's actions with a touch screen interface to be associated with a consumer-profile. l) to provide a method that allows the use of motion sensors to track consumer movements and associate these actions with a consumer profile. m) to provide a method that allows the use of touch sensors to track consumer actions and associate these actions with a consumer profile. n) to provide a method that allows the recorded actions of a registered user to be used to customize the user's retail experience. o) to facilitate user interactions with the automated vending process or retail display by providing a visual reminder of products that have already been selected or previously purchased in another session by the user on the touch screen so that they can be easily purchased again. p) to provide the ability for a user to customize their own experience through voluntary information input. q) to provide the ability for a user to manage their methods of contact which may include but are not limited to email address, phone, cell phone, facsimile machine phone number, social media website user identification, or mailing address. r) to provide the ability to remotely manage all of the registered users preferences and accessible information via a website or mobile application. s) to provide a method that allows administrative users to place time restrictions on a registered user's ability to receive product samples. t) to provide a method that allows administrative users to place quantity restrictions on a registered user's ability to receive product samples. u) to provide a system and a method for linking user registration made on one machine to all machines on the system via a central repository and management system. v) to provide system wide restrictions and limitations on sample programs and other membership benefits across all machines connected to a central system.
[0056] These and other objects and advantages of the present invention, along with features of novelty appurtenant thereto, will appear or become apparent in the course of the following descriptive sections.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0057] In the following drawings, which form a part of the specification and which are to be construed in conjunction therewith, and in which like reference numerals have been employed throughout wherever possible to indicate like parts in the various views:
[0058] FIG. 1 is a block diagram of the system.
[0059] FIG. 2 is an isometric view of an assembled vending machine module.
[0060] FIG. 3 is a software block diagram of the preferred “general user lookup process”;
[0061] FIG. 4 is a software block diagram of the preferred “new user registration process”;
[0062] FIG. 5 is a software block diagram of the preferred “returning user lookup process”;
[0063] FIG. 6 is a software block diagram of the preferred “update account information”and “add additional identifying methods” processes;
[0064] FIG. 7 is a software block diagram of the preferred “member transaction process”;
[0065] FIG. 8 is a software block diagram of the preferred “sample dispensing process”; and,
[0066] FIG. 9 is a software block diagram of the preferred “end of session process.”
DETAILED DESCRIPTION OF THE INVENTION
[0067] With initial reference directed to FIGS. 1 and 2 of the appended drawings, a system consisting of a plurality of automated retail machines connected via a data connection to a centralized, backend operations center system has been generally designated by the reference numeral 100 . At least one automated retail machine 101 is deployed in a physical environment accessible by a consumer who can interact with the machine 101 directly. There can be any number of machines 101 , all connected to a single, remote logical operations center 130 via the Internet 120 (or a private network).
[0068] The operations center 130 can physically reside in a number of locations to meet redundancy and scaling requirements. The machine software is composed of a number of segments that all work in concert to provide an integrated system. Logical area 102 provides the interface to deal with all of the machine's peripherals such as sensors, keypads, printers and touch screen. Area 103 handles the monitoring of the machine and the notifications the machine provides to administrative users when their attention is required. Area 104 controls the reporting and logging on the machine. All events on the machine are logged and recorded so they can be analyzed later for marketing, sales and troubleshooting analysis. Logical area 105 is responsible for handling the machines lighting controls.
[0069] Logical area 106 is the Inventory Management application. It allows administrative users on location to manage the inventory. This includes restocking the machine with replacement merchandise and changing the merchandise that is sold inside the machine. Administrative users can set the location of stored merchandise and the quantity.
[0070] Logical area 107 is the retail store application. It is the primary area that the consumers use to interface with the system. This is the area that the majority of the processes described in FIGS. 3 through 9 occur. Logical area 108 handles the controls required to physically dispense items that are purchased on the machine or physically dispense samples that are requested by a consumer. Logical area 109 controls the inventory management system allowing authorized administrative users to configure and manage the physical inventory in the machine. Area 110 controls the payment processing on the machine. It manages the communication from the machine to external systems that authorize and process payments made on the machine. Area 111 is an administrative system that allows an authorized user to manage the content on the machine. The content can consist of text, images, video and any configuration files that determine the user's interaction with the machine.
[0071] The latter applications interface with the system through m application layer designated in FIG. 1 by the reference numeral 112 . This application layer handles the communication between all of these routines and the computer's operating system 113 . This layer provides security and lower level messaging capabilities. It also provides stability in monitoring the processes, ensuring they are active and properly functioning. Logical area 131 is the user database repository that resides in the operations center 130 . This repository is responsible for storing all of the registered user data that is described in the following figures. It is logically a single repository but physically can represent numerous hardware machines that run an integrated database. The campaign and promotions database and repository 132 stores all of the sales, promotions, specials, campaigns and deals that are executed on the system. Both of these databases directly interface with the real-time management system 133 that handles real-time requests described in FIGS. 3 and 9 . Logical area 134 aggregates data across all of the databases and data repositories to perform inventory and sales reporting. The marketing management system 135 is used by administrative marketing personnel to manage the marketing messaging that occurs on the system: messages are deployed either to machines or to any e-commerce portals. Logical area 136 monitors the deployed machines described in FIG. 2 , and provides tools to observe current status, troubleshoot errors and make remote fixes. Logical area 137 represents the general user interface portion of the system. This area has web tools that allow users to manage their profiles and purchase products, items and services. The content repository database 138 contains all of the content displayed on the machines and in the web portal. Logical area 139 is an aggregate of current and historical sales and usage database comprised of the logs and reports produced by all of the machines in the field and the web portals.
[0072] FIG. 2 shows an automated retail vending machine 200 that was represented logically as 101 ( FIG. 1 ). For purposes of vending machine hardware disclosure, the two following co-pending U.S. utility applications, which are owned by the same assignee as in this case, are hereby incorporated by references, as if fully set forth herein:
[0073] (a) Pending U.S. utility application Ser. No. 12/589,277, entitled “Interactive and 3-D Multi-Sensor Touch Selection Interface For an Automated Retail Store, Vending Machine, Digital Sign, or Retail Display,” filed Oct. 21, 2009, by coinventors Mara Segal, Darrell Mockus, and Russell Greenberg, that was based upon a prior pending U.S. Provisional Application, Ser. No. 61/107,829, filed Oct. 23, 2008, and entitled “Interactive and 3-D Multi-Sensor Touch Selection Interface for an Automated Retail Store, Vending Machine, Digital Sign, or Retail Display”; and,
[0074] (b) Pending U.S. utility application Ser. No. 12/589,164, entitled “Vending Machines With Lighting Interactivity And Item-Based Lighting Systems For Retail Display And Automated Retail Stores,” filed Oct. 19, 2009 by coinventors Mara Segal, Darrell Mockus, and Russell Greenberg, that was based upon a prior pending U.S. Provisional Application, Ser. No. 61/106,952, filed Oct. 20, 2008, and entitled “Lighting Interactivity And Item-Based Lighting Systems In Retail Display, Automated Retail Stores And Vending Machines,” by the same coinventors.
[0075] Again referencing FIG. 2 , and as detailed in the above-mentioned copending utility applications, the display module 210 can be attached with a hinge 226 to a vending machine comprised of a rigid upright cabinet with rigid sides 223 and top 224 , or the module can be mounted to a solid structure as a stand-alone retail display. The display module 210 forms a door that is hinged to the cabinet sides 223 adjacent a vertical control column 211 . A variety of door configurations known in the art can be employed. For example, the display doors can be smaller or larger, and they can be located on one or both sides of the totem area. The display doors can have multiple square, oval, circular, diamond-shaped, rectangular or any other geometrically shaped windows. Alternatively, the display area can have one large display window with shelves inside.
[0076] A customizable, lighted logo area 201 ( FIG. 2 ) is disposed at the top of column 211 . Touch screen display 202 is located below area 201 . Panel 203 locates the machine payment system, coin acceptor machine or the like. Additionally panel 203 can secure a receipt printer, keypad, headphone jack, fingerprint scanner or other access device. The product retrieval area 204 is disposed beneath the console 211 in a conventional compartment (not shown). A key lock 205 , which can be mechanical or electrical such as a punch-key lock, is disposed beneath the face of the module 210 . One or more motion sensors 206 are disposed within smaller display tubes within the console interior. There are a plurality of generally circular touchable product viewing areas 207 areas defined upon the outer the face of the casing 208 that are aligned with internal display tubes behind the product viewing surface areas. Areas 207 include proximity or touch sensors described hereinafter that are used for customer selection. The reference numeral 209 designates an exterior antenna that connects to a wireless modem inside the machine providing connectivity.
[0077] FIG. 3 illustrates a general user lookup subroutine 300 that determines whether a user is registered. Subroutine 300 begins on a deployed machine 101 ( FIG. 1 ) when a user attempts to access an area or feature restricted to registered users of the system 301 , or when a user actively touches a button or control on the touch screen (i.e., in area 102 ) indicating they wish to identify themselves as a registered user 302 . This functionality takes place within the retail store application 107 ( FIG. 1 ). The user is presented with a screen prompting them to register or identify themselves with an existing registration identification method in step 303 . The user may use any of the accepted methods of identification as noted previously in this document.
[0078] Step 304 handles all methods that involve insetting or swiping an identifying piece of information such as a credit card, membership card, driver's license, etc. Step 305 handles all identification methods that are entered into the system via the touch screen and/or keypad devices. These methods typically include usernames and passwords. Step 306 handles any method that is sensed, detected or scanned such as wireless devices, fingerprints, facial recognition or wireless emitting entities such as smart cards. Each of these steps has their own error handling procedures that make sure the information is read or entered in correctly. Step 307 packages this information into a formatted message requesting identification verification. This step can include encrypting the data or using a hash function that converts a set or subset of the possibly variable-sized amount of input data into a small datum, usually a single integer that may serve as an index to the user record. The inputted data is never transmitted or stored in its raw form. From this point on, the fell data set cannot be reverse computed to get the original value. Step 308 sends the identification authorization request to the central operations center 130 ( FIG. 1 ) represented by the processes indicated by 310 . It is received by the Real-time Management System 133 ( FIG. 1 ) in step 311 that parses the message and extracts the identifying pieces of information used to lookup the user record based on the identification method supplied. Step 312 attempts to lookup the registered user stored in the user database repository 131 ( FIG. 1 ). Step 313 examines the information received from the query in step 312 . If an exact unique match was found based on the hash id, the process moves to step 318 where a message is formulated that indicates an exact match was found and the data, being returned is a specific registered user associated with the identification information provided. If an exact match was not found, the system executes step 314 that attempts to determine if this user, while registered, is using an alternative method of identification that is not stored in the system yet by examining some of the non-unique information supplied, such as the name. For example, the user may be using a different credit card than they used the first time. In this case, the name matches but not the hash id calculated by the system to represent the data on the card. Step 314 attempts to use whatever identifying information sent to match registered user records in the user database repository 131 ( FIG. 1 ). Since this partial information does not make a unique match, the result set will be an array of one or more registered user records or a null dataset in the event nothing is found that matches. This result set is tested in step 315 . If no data was found that matched any of the provided information, a message is formatted that there is no registered user that matches the identifying information provided in step 317 . If some results were found, step 316 formats a message that one or more registered users may match the information provided. The message will contain the registered user records of any potential match. Included in the method will be additional pieces of information that can be used by the local process on the machine sending the request to verify the user. Step 319 packages the message and sends to the machine that made the original authentication request. It then sets a timer, and waits for a receipt from the machine that the message was received. Step 320 monitors the elapsed time, and compares it to a value set by an administrative user in the configuration file. If the elapsed time exceeds that set time, the message is resent until the maximum number of attempts is reached according to the administrative configuration file, otherwise, the process terminates at 321 . Step 322 occurs on the deployed machine represented logically as 101 ( FIG. 1 ) that made the original request. It listens for a response from the Real-time Management System 133 ( FIG. 1 ). If it receives a message, it sends a receipt message which is handled by the process in step 319 . Step 322 directs the information received to subroutine processes 400 , 500 , 600 , 700 or 800 that originated the request for the general lookup subroutine 300 to be executed, which are described below and detailed in FIGS. 4-8 .
[0079] Subroutine 400 ( FIGS. 3 , 4 ) is preferred for registering a new user. Subroutine 400 begins either when a user attempts to register as described above per subroutine 300 , or when a user attempts to enter a system area that requires the user to be a member, as indicated by step 401 , wherein the user is directed to the general lookup subroutine 300 ( FIG. 3 ). The result set is returned to step 402 where it examines the data to determine if there were any matches found in the user database. If an exact match is found, that user is classified as a registered user, and the Update Account Information subroutine 600 commences. If the general lookup subroutine 300 does not indicate a preexisting unique, user account, step 403 checks to see if subroutine 300 returned an array of possible users in step 403 . If an array of possible users is found, the step 404 prompts the user for a secondary piece of information based on the method they are using to identify themselves, and checks that against the information returned from the server for a possible match in step 404 . Step 405 determines if the data matches any previously registered user's information. If there is a match, the user is directed to the Update Account Information Subroutine 600 ( FIG. 6 ). If there is no match in step 405 , the user is directed into the user registration process by prompting them to accept the required legal agreements concerning use of this system, privacy agreements, or any other possible legal agreement or acknowledgement in step 408 . If in step 403 , it is determined that no matches of any sort were returned from the general lookup process 300 , then the system prompts the user for a secondary identifying method in step 406 . Error handling is done in step 407 to ensure that the information is in a valid formal. If it is not, the user is prompted to correct in the information in step 406 , otherwise, the user is prompted to accept the legal agreements required to use the system in step 408 .
[0080] Step 409 evaluates the user's answer to the question in step 408 . If the user did not accept the legal agreement, they are not permitted to use the system and they will get a failed registration message in step 410 . They are given the option of accepting the agreement again at step 408 or terminating the user registration process in step 411 . If the user accepts the agreement, they are directed to step 412 , where they are prompted for their acceptance of various types of marketing communication. The users selections are stored in a local memory in step 413 and the user is prompted to add additional forms of communication in step 414 . This is an optional area where the user can add an additional form of contact such as a cell phone, mailing address, or any other mechanism through which he or she may be reached. Step 415 performs error checking on the information entered in step 414 . If the information is not correct or has an error, the user can fix the issue, otherwise, the user is prompted with the option to indicate additional preferences in step 416 . Optional preferences include information concerning which products or brands interest the user, categories of products frequently purchased, communication preferences, demographic data or any other marketing related information that the user volunteers. The data is recorded in local storage on the machine in step 417 . In step 418 , the local session variable is set to indicate that a registered user is now using the machine. This opens up access by the user to registered areas of the machine, and gives the registered user privileges that are associated with an account at the introductory level as they use the machine in a normal user session in step 419 . When the application determines that the session is over through any means such as a completed transaction, idle period, a user-instigated end session (indicated though a control button on the touch screen), or any other terminating event, the session end subroutine 900 is initiated.
[0081] Subroutine 500 ( FIG. 5 ) illustrates the preferred returning user identification process. It outlines the process whereby a user is identified on a machine, and associates their user session with their existing registered account. Identifying oneself as a registered user on a machine gives the user access to member restricted areas and benefits.
[0082] The returning-user identification process begins in step 501 when a user selects a control on the touch screen to indicate that they are a returning user, or the general lookup process 300 returned with an array of user data. The system checks if user data is present in step 502 . If no user data is present the application prompts the user to identify themselves through a preferred method in step 503 . The user can use any of the accepted methods of identifying themselves on a machine if they had previously filled out the proper information to do so. Accepted methods include the use of data on a credit card magnetic stripe, indicating a registered cell phone number with a personal identification number, inputting a user name and password, fingerprint scanning, or any other identification routine that provides a unique and secure combination. Step 504 verifies that this information was entered and read by the system correctly. If not, the user is prompted to again enter their information via step 503 . If the information was read correctly, it is formatted and sent to the general lookup process 300 .
[0083] In step 505 , information returned from step 300 ( FIG. 5 ) is examined. If no user data is found, the information supplied cannot be associated with any existing account, and the user will be routed to the new user registration process 400 . If user data was found, step 506 determines if the general lookup process 300 found an exact match and returned a specific user GUID or an array of possible user GUIDs and associated user information. If a specific user was matched exactly to the information provided, the application triggers step 509 . If an exact match was not found, the system will prompt the user for additional information from their profile in an attempt to securely match them up with existing user registration files in step 507 . Step 508 determines if this matching was successful. If it was not, the user is directed to the new user registration process 400 . If a user was successfully matched to information provided in step 506 or step 508 , step 509 will be triggered. Step 509 will set the session variables on the local machine with the registered user's GUID. The user would be returned to their user session 510 on the machine. The user will now have access to member areas until the end of their session. Actions and transactions during this active and continuous session will be logged and noted on their account. When the application determines the session is over through any means such as a completed transaction, idle period, user instigated through an end session control button on the touch screen or any other terminating event, the session end process 900 is initiated.
[0084] Subroutine 600 ( FIG. 6 ) allows a user to update and manage their account information. It accommodates various ways for a user to edit, update, and manage their account information. A user must have been previously registered and identified as a registered user on a machine in an active session in order to have access to this process.
[0085] The process begins in step 601 when the user selects a command button on the user interface that directs then into the update account information area, or the user is prompted automatically to this area in the case that it is determined that the user needs to update their account information. Reasons for automatically prompting a user to update their account status could be that the legal agreements they previously accepted have changed, new options or preferences are now available since their last user session, or that a specified time has elapsed since the last time a user has updated their information. Information is pulled from local storage on the machine and formatted for onscreen presentation in step 601 . This locally stored information was previously retrieved by process 400 ( FIG. 4 ). This screen displays their currently stored information, a summary of their information, or selections to specific segments of their account information. The user is prompted to edit information on the main management screen in step 603 . From this step, they can edit multiple areas or indicates that they are finished, which triggers step 604 and sends the user back to their user session. If the elects to update their marketing message preferences, they are routed to step 605 where they may make changes. Step 606 stores the changes made in a local storage area on the machine. Afterwards, the user is returned to step 603 where they may indicate that they are done in step 604 , or they may make another selection. Alternatively, from step 603 , the user may opt to add an additional identifier method to their user profile in step 607 . The identifier method can be any of the previously mentioned methods that provide a unique and secure identifying mechanism. Step 608 validates this information and provides error checking. If there are problems, the user is prompted to correct the problems. If there are no problems, the user is directed to step 606 that saves the new information in a local storage area where it will later be uploaded to the central repository during the end of user session 900 . After the data is stored locally in step 606 , the user is returned to the main user management area 603 . The user may also opt to update their demographic profile, contact information, retail profile or product and brand preferences in step 609 . After the changes, the user can confirm the changes and store them locally in step 606 , or they can cancel the operation returning to step 603 where they may make another selection or complete their updating selecting that they are done triggering step 604 . The user is then returned to their user session 620 . When the application determines the session is over through any means such as a completed transaction, idle period, user instigated through an end session control button on the touch screen or any other terminating event, the session end process 900 is initiated where the information stored locally in this process is uploaded to the user repository 131 ( FIG. 1 ).
[0086] FIG. 7 illustrates the preferred method of conducting a transaction to determine if a user is a registered user or not. This method provides a way to link transactions on a machine to a registered user if they previously registered. The benefit of this method is that if a user was already registered with the same payment method they are currently using, they are automatically logged into the system. If they are not a registered user, they are given the option to register with the system before completing their transaction.
[0087] The payment subroutine 700 ( FIG. 7 ) begins when a user indicates that they are ready to pay for their purchase in step 701 . Step 702 cheeks if they are already identified in the current session as a registered user of the system. If the current user is identified as a registered user of the system, they proceed directly to the standard checkout validation process 711 . The checkout validation process is a standard vending process ensures payment is received before products or merchandise are vended. The system described here uses an external payment authorization system supplied by a third party vendor. These third party vendors have systems that will receive payment information (e.g. identifying credit information from a credit card) and determine if it is a valid payment method and if the amount to be charged is within the credit limits of this card. The process is the same for debit transaction where the identifying debit information is matched to a debit account, validated through their own processes and analyzed to see that the amount being debited is available. The checkout process 711 receives a success response from this third party system if the amount has been charged or debited. If a successful transaction occurs, the selected merchandise is vended. If a failure response is received for any reason, the transaction is suspended and the user is notified. At this point they may try to use another form of payment or cancel the transaction. The system can use any one of these third party payment authorization systems that are widely available to purchase as a service.
[0088] If the current user is not already identified with the machine as an active user, they are prompted if they want to register or identify themselves as a registered user on the system in step 703 . If they do not, the event is logged, and the user is directed hack to the transaction process 711 as described above. If the user wishes to register or indicates they are an existing registered user, they are queried to specify which one they are in step 704 or select that they wish to cancel. If they select cancel, the user is directed to the checkout process 711 . If the user indicates they are an existing registered user, they are asked to identify themselves with the system in step 705 . The information is captured and a validation request is sent to the general lookup process 300 ( FIG. 3 ).
[0089] The data returned from the general lookup process is analyzed in step 707 . If no user is found, the user is directed to the new user registration process 400 ( FIG. 4 ). If some user data was found, step 708 determines if an exact match to a registered user was found. If a single registered user was found that exactly matched to the data provided, the user proceeds to the standard checkout process 709 . If an exact match was not found, the general lookup process returned an array of possible registered users and the user is directed to step 710 where they are prompted for additional information that will be user to try to match the current user with an existing user registration. If the information provided by the user did not match up with any record in the array returned by the general lookup process, the user is directed to the new user registration process 400 ( FIG. 4 ) where they may complete the registration process or cancel. If the validation data entered in by the user in step 710 matches a record in the array or if the user successfully completes the new user registration process 400 ( FIG. 4 ), the event is logged and the session variable is set to indicate the current user is a registered user in step 706 . The process then continues to the checkout process 711 where the user's payment information is validated as described above.
[0090] After the user completes the standard checkout process, the session variable is checked to determine if the current user is a registered user. If they are not, the process terminates in step 713 . If the current user is a registered user, step 714 records the transaction information in local storage associating the information with the registered user's GUID. The process then proceeds to step 715 that displays summary information of the transaction to the user. This information may include information such as the total accumulated rewards points, special offers targeted at that registered user or additional options available to registered users which may be configured by administrative users of the system. The user's session is then automatically terminated by step 715 and the process ends with the session end process 900 .
[0091] FIG. 8 illustrates the preferred method of handling sample dispensing within the context of the customer retention system outlined herein. The user registration process is compulsory. A user must register in order to receive a free sample on the system. A user must either register with the system or have previously registered with the system in order to be eligible for a sample. The user is also subject to the rules of the program which may be configured to restrict the dispensing of samples. The user restrictions on the sample program can be programmed into the system through a graphical user interface by non-technical personnel. This system allows an administrative user to set time and quantity limits on the samples that are dispensed per user. The time limits restrict the time between dispensing samples. For example, member users can be restricted to receiving only one sample product per 24 hour period. The quantities of a particular type of sample can also be restricted. For example, a user may be restricted to receiving only one type of sample per member account. The restrictions are enforced across all machines on the system via the centralized operations center described in FIG. 1 . This is advantageous as a consumer within range of a number of deployed machines cannot abuse the sample dispensing system.
[0092] The membership sample subroutine 800 begins when a user attempts to obtain a sample from the machine in step 801 (depicted logically as 101 in FIG. 1 and physically as 200 in FIG. 2 ). The current session variables are checked in step 802 to see if the current user is identified as a registered user. If the current user is not identified as being a registered member, they are prompted in step 803 to identify themselves using an acceptable method of identification. This information is sent to the general lookup process 300 ( FIG. 3 ). The results of the lookup are tested in step 804 . If general lookup subroutine 300 does not produce a matching result set, the user is sent to the new registration subroutine 400 ( FIG. 4 ). If the general lookup process produces a result set of an array of one or more member user registration data sets, it is checked in step 805 . If the result set does not contain an exact match, the user is prompted for additional identifying information in step 806 . Step 807 examines the additional information entered by the user. If there is not a match of the additional information to any of the result set returned by the general lookup process, the user is directed to the new user registration process 400 ( FIG. 4 ). If the information does match one of the registered user data sets returned by the general lookup process, then the user is directed to step 808 where the session variable is set indicating that the current user is a registered member. Step 808 will also store the user data received in step 803 in the matched user record. This will permanently associate the new identifying data with the users registered account data. If step 805 determines that there is an exact match of a registered user's data record, the user would proceed to step 808 where the session variable is set indicating that the current user is a registered member. The user is then directed to step 809 that retrieves the user's sample dispensing history that is attached to their user record retrieved by the general lookup process 300 ( FIG. 3 ). This data is matched against the administrative settings for possible limits placed on the sample dispensing program. If step 802 determined that the current user was a registered user, it will have sent the user to step 809 bypassing any additional lookups. Step 810 determines if the registered user is within the time constraints set on the sample program. The user is sent to step 811 if the user did not meet the limits set on the time meaning the administrative set time has not yet elapsed since the user received their last sample. Step 811 displays a user message that they are not eligible for the dispensing of that sample at this time. If the registered user did meet the time constraints placed on the sample being dispensed, they proceed to step 812 that determines if the registered user meets the quantity constraints placed on the sample they are attempting to receive. If the user has exceeded the allowed quantity for the particular sample they are attempting to receive, they do not meet the quantity limit rules and are directed to step 811 that displays a message to the user that they are not eligible to receive the sample they requested at this time. If step 812 determines they are eligible to receive this sample, the user proceeds to the system sample dispensing procedure that handles the physical dispensing of the sample product in step 813 . Step 814 records the results of the sample dispensing process and updates the current user's sample dispensing history data set. The user then returns to their current user session 815 . When the application determines the session is over through any means such as a completed transaction, idle period, user instigated through an end session control button on the touch screen or any other terminating event, the session end process 900 is initiated where the information stored locally is this process is uploaded to the user repository 131 ( FIG. 1 ).
[0093] Subroutine 900 ( FIG. 9 ) handles a registered user's data at the end of a user session on a machine. When the application determines the session is over through any means such as a completed transaction, idle period, user instigated through an end session control button on the touch screen, or any other terminating event, the session end is initiated. This process gathers all new data logged during a registered user's session and sends this information hack with the machine identification number to the central server and user repository to store. This information resides there until it is retrieved by the user initiating a new user session on a machine, accessed by an administrative user for management purposes, or used by an automated or manual process for marketing or data analysis purposes. After an acknowledgement that the information was successfully received and stored in the user repository, the local machine removes the locally stored data from its memory.
[0094] The session end subroutine 900 begins when the application determines that a registered user's session has ended 901 . Step 902 processes all of the newly recorded information associated with the registered user's account The current machine identification number is attached to this information. Step 903 packages this information into a formatted message and sends to the central operations center 130 ( FIG. 1 ) where it is processed by real-time management system 133 ( FIG. 1 ) and stored in the user database repository 131 ( FIG. 1 ). Steps 904 , 905 , 906 , 907 , 908 , 909 , 910 , and 911 take place in the central operations center 130 ( FIG. 1 ). The computations are performed by the real-time management system 133 ( FIG. 1 ) and the data storage is recorded in the user database repository 131 ( FIG. 1 ).
[0095] Step 904 parses the incoming message and notes the user identification parameters and the machine identification number. Step 905 users the user information to locate the correct user record. Step 906 determines if a user is found. If a user is not found, step 907 stores the information in a temporary folder where an administrator will manually analyze it at a later time. If step 906 determines that a user record was successfully found, step 908 stores the information in the user database repository 131 ( FIG. 1 ). Step 909 creates a message that the information was received and stored successfully in the user database, sends that message to the machine that initiated the original message and waits for a response. Step 912 occurs on the originating machine. It receives the message, removes the user data recorded in the session from the local machine and sends an acknowledgement response hack to the central operations center. The process on the local machine then terminates 913 . If an acknowledgement message is received during the specified time, the process ends in step 911 . If the specified time elapses and no acknowledgement message is received, step 909 will resend the message.
[0096] From the foregoing, it will be seen that this invention is well adapted to obtain all the ends and objects herein set forth, together with other advantages which are inherent to the structure.
[0097] It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.
[0098] As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense. | A vending system comprising numerous remote vending machines, retail displays, and automated retail stores connected to a communication network access a central database so that each remote machine provides and responds to personalized customer information. Each machine comprises a display containing products to be vended and a plurality of touchable product viewing areas for initiating a vend. A computer recognizes customer data derived from peripheral inputs. Software communicates with the database for establishing customer profiles and either recognizing customers or registering customers by generating a global unique identifier. Subroutines initiate the dispensing of items in response to preselected conditions associated with each GUID. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a horizontal drive circuit for a CRT (cathode ray tube) display, and more particularly, to a horizontal drive circuit which uses a switch-mode power supply operating in a boost topology to generate an appropriate supply voltage needed by the horizontal drive circuit.
2. Background of the Invention
The most commonly used method to provide power to a horizontal drive circuit, with voltage adjustment capability, is to use the RegB+ of the horizontal output stage (usually around 130 VDC) in series with power resistors to reduce the 130 VDC to approximately 65 VDC. FIG. 1 illustrates this conventional horizontal drive circuit 100 which includes capacitor 108 , a flyback transformer 112 , and a horizontal drive transistor 116 being driven by a horizontal drive IC (integrated circuit) 114 . The RegB+ voltage is applied to the circuit 100 at connection 102 and supplies a proper voltage level at connection 110 by reducing the voltage through power resistors 104 , 106 .
By changing the value of the resistors 104 , 106 , one can adjust the horizontal drive supply voltage 110 . For example, typically two (2) 5W resistors (either placed in series or parallel with a typical equivalent value of 1.5 Kohm to 4.7 Kohm) are used to drop a supply voltage to the horizontal driver circuit to an acceptable/useable voltage. The wattage of the resistors needs to be large enough to handle a fault condition of a shorted driver transistor 116 . This method is costly, requires large power resistors (due to fault conditions) which waste printed circuit board (PCB) space, and is not efficient (power is wasted in dropping resistors).
A possible solution would be to have a separate Buck-Boost Switch-mode Supply generating the appropriate horizontal drive voltage which uses its own control IC (integrated circuit) and switching device. However, this solution would require more printed circuit board area and would also have higher costs.
Therefore, a horizontal drive circuit is needed that advantageously combines the separate functions of a boost power supply with a horizontal drive circuit that occupies less printed circuit board area and achieves higher efficiency at lower cost.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a horizontal drive circuit incorporating a boost switch-mode power supply.
It is another object of the present invention to provide a horizontal drive circuit incorporating a boost switch-mode power supply that occupies less printed circuit board area than the conventional combination of a horizontal drive circuit and associated power supply.
It is a further object of the present invention to provide a horizontal drive circuit incorporating a boost switch-mode power supply that achieves higher efficiency over many different horizontal frequencies.
Another object of the present invention is to provide a horizontal drive circuit incorporating a boost switch-mode power supply that can handle a fault condition of a shorted drive transistor without the use of large power resistors.
To achieve the above objects, a horizontal drive circuit employed in CRT displays which uses a switch-mode power supply operating in a boost topology to generate the appropriate supply voltage needed by the horizontal drive circuit is provided. The boost power supply is integrated into the horizontal drive circuit which allows for low printed circuit board area, low cost, and good performance over many different horizontal frequencies. A means of voltage adjustment and fault protection are also provided.
According to an aspect of the present invention, a horizontal drive circuit includes a flyback transformer having a first end of a primary coil connected in parallel to a capacitor and a second end of the primary coil connected to a horizontal drive transistor, and a boost switch-mode power supply. The boost switch-mode power supply includes an input voltage; a power bus including an inductor for receiving the input voltage and a first diode connected in series; and a switching means connected between the second end of the primary coil and a junction between the inductor and the first diode. Preferably, the switching means takes the form of a second diode. The boost switch-mode power supply further provides a voltage adjustment means through the use of a resistor.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present invention will become more apparent in light of the following detailed description of an exemplary embodiment thereof taken in conjunction with the attached drawings in which:
FIG. 1 is a schematic diagram illustrating a conventional horizontal drive circuit;
FIG. 2 is a conventional boost circuit for increasing the voltage level of a supply voltage; and
FIG. 3 is a schematic diagram illustrating a horizontal drive circuit incorporating an integrated boost switch-mode power supply in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the present invention will be described hereinbelow with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail to avoid obscuring the invention with unnecessary detail.
This invention comprises the combination of the separate functions of a boost power supply with a horizontal drive circuit. By integrating both functions into one circuit, the advantages of less board space, higher efficiency, lower cost, with adequate fault protection and voltage adjustability are achieved.
FIG. 2 illustrates a schematic diagram of a conventional boost circuit 200 . Boost circuit 200 includes a power bus including an inductor 204 connected in series with a diode 208 . A switch 206 is connected at a junction of the inductor 204 and the diode 208 and a capacitor 210 is connected at the cathode side of the diode 208 where an output voltage 212 can be measured. The transfer function of boost circuit 200 is determined by the following equation (1):
V out= V in/Duty cycle of switch (1)
For example, if switch 206 is operating at a 50% duty cycle, the output voltage, Vout, 212 will equal two times the input voltage, Vin, 202 . By incorporating a boost power supply, the horizontal drive circuit becomes much more efficient, since it is not dissipating power through resistors as described above in conjunction with FIG. 1 .
FIG. 3 is a schematic diagram illustrating a horizontal drive circuit 300 in accordance with the present invention. Referring to FIG. 3, the circuit 300 of the present invention includes a boost power supply circuit 302 and a horizontal drive circuit 350 . The boost power supply circuit 302 includes an inductor 304 , a first diode 306 , a second diode 308 and resistor 310 . The horizontal drive circuit 350 includes a capacitor 352 , a flyback transformer 354 , and a horizontal drive transistor 356 being driven by a horizontal drive IC (integrated circuit) 358 . The horizontal drive circuit 350 is configured analogously to the corresponding portion of FIG. 1 described above. The inductor 304 and diode 306 are connected in series with the horizontal drive side of flyback transformer 354 , and diode 308 and resistor 310 are connected in series with the opposite end of flyback transformer 354 .
As shown in FIG. 3, the switching function accomplished by switch 206 in FIG. 2 is implemented by diode 308 . By utilizing diode 308 , the horizontal drive circuit 350 of the present invention can advantageously use the horizontal drive pulse, generated by the horizontal drive IC 358 , to drive both the boost supply and the horizontal drive transistor 356 . This IC 358 is one small part of a signal chain starting from a typical tuner, for example a television tuner. The tuner receives a modulated TV signal from the air and the signal “chain” demodulates the signal and separates the signal into audio, luminance, chroma, and synchronizing components. The horizontal drive signal is generated from the synchronizing component of the input signal and is commonly referred to as horizontal sync. This horizontal sync signal is converted into approximately a 50% duty cycle signal by the signal processor IC and sent to the horizontal drive circuit. This duty cycle can be 40% for some processors and is always fixed in the IC.
Horizontal drive circuit 300 further includes resistor 310 as a means for adjusting the voltage for the horizontal drive voltage. When horizontal drive transistor 356 turns on, it pulls current through inductor 304 , diode 308 and resistor 310 . A voltage develops across resistor 310 due to this current. This voltage reduces the current by reducing the forcing voltage across inductor 304 . Due to volt second balance across inductor 304 (since an ideal inductor cannot have DC voltage across it), the voltage developed across resistor 310 reduces the “flyback” voltage at the anode of diode 306 when the horizontal drive transistor 356 is turned off. This, in turn, reduces the boost horizontal drive voltage seen at the cathode of diode 306 thereby allowing a means of adjustment. The larger the value of resistor 310 the smaller horizontal drive voltage. For example, the maximum horizontal drive voltage would be approximately two times +35 VDC or 70 VDC. The minimum horizontal drive voltage with resistor 310 open would equal +35 VDC. By adjusting resistor 310 , a horizontal drive voltage between 70 VDC and 35 VDC can be achieved. Of course, the more the horizontal drive voltage is reduced, the more power is dissipated in resistor 310 . Therefore, a practical adjustment range is 10% to keep the resistor 310 below ½ Watt.
The horizontal drive circuit of the present invention provides for better fault protection. If the horizontal drive transistor 356 shorts, then diode 306 is pulled to ground. If the inductor's 304 resistance is kept to a minimum (about 2 Ohms), then resistor 310 will now see +35 VDC across it. Since Power=V2/R, resistor 310 will see 10 Watts, assuming resistor 310 is at a maximum value of 120 Ohms. If resistor 310 becomes a fusible resistor, then it will open safely without exceeding design temperature guidelines of 95° C., at what point the solder securing the resistor would become molten.
Since the horizontal drive circuit 300 operates on a “duty cycle” basis, it is very tolerant to horizontal drive frequency changes. This is important due to the many TV standards currently employed. This means the horizontal drive frequency can vary between one to three times the frequency with insignificant change to the horizontal drive voltage because the duty cycle voltage stays the same.
Constraints
Inductor 304 must be high enough in inductance to keep the current continuous. If the current goes discontinuous, then ringing will occur on the drive waveform and also the supply voltage will increase. This is due to the effective duty cycle changing due to the discontinuous current operation. Therefore, the inductance value would be set using the input DC voltage and the minimum operating frequency.
While the present invention has been described in detail with reference to the preferred embodiments, they represent mere exemplary applications. Further, the invention can find use in other applications and/or devices besides CRT displays. Thus, it is to be clearly understood that many variations can be made by anyone having ordinary skill in the art while staying within the scope and spirit of the present invention as defined by the appended claims. | A horizontal drive circuit employed in CRT displays which uses a switch-mode power supply operating in a boost topology to generate the appropriate supply voltage needed by the horizontal drive circuit is provided. The boost power supply is integrated into the horizontal drive circuit which allows for low printed circuit board area, low cost, and good performance over many different horizontal frequencies. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to sprinklers, especially to sprinklers for supplying water to lawns and other vegetation. A particular feature of the invention is a novel water distributor head.
For many years a great deal of effort has been devoted to developing sprinklers for lawn, crops, etc. These devices have varied widely in complexity, ranging all the way from simple spray nozzles to complex assemblies having water-driven gears and a large number of moving parts. For greatest efficiency, a sprinkler should have a minimal number of moving parts, be designed so that the supply stream of water is not subjected to excessive friction, deliver water in a manner that minimizes loss by evaporation, and be capable of covering a large area. While many prior art sprinklers have possessed some of these characteristics, it is believed that none has possessed all of them.
Illustrative of the prior art devices is that shown in Swan U.S. Pat. No. 2,761,738, where a stream of water impinges on a vaned perforate rotor to distribute droplets instead of a fine spray. Jones U.S. Pat. No. 3,567,124 likewise employs a rotating unit to distribute water over the area to be sprinkled. Rider U.S. Pat. No. 1,893,210 describes a sprinkler having an internally grooved nozzle that is said to deliver water in "gobs or slugs." Hait U.S. Pat. Nos. 3,009,647 and 3,009,648 describe rubber whip type sprinkler heads. Hruby U.S. Pat. Nos. 3,081,036, 3,175,767, 3,347,464, and 3,357,643 all describe sprinklers in which a tubular water distributing stem gyrates around in a tubular body.
Clearman U.S. Pat. No. 2,848,276 discloses a sprinkler utilizing a novel distributor head in which an upwardly directed jet of water strikes the lower surface of an externally grooved inverted conical diverter, which "wobbles", or precesses, to distribute coarse drops of water throughout a circular area. This device is extremely simple and efficient, but the area watered is not so large as is frequently desired.
BRIEF SUMMARY
The present invention provides a sprinkler device incorporating a novel water distributor head. The device is simple and inexpensive to manufacture, employs a small number of moving parts, delivers water with minimum loss by evaporation, and is able to supply water to an extremely large area. Like the distributor head of the aforementioned Clearman patent, the distributor head of the present invention traverses a wobbling, or precessing, path.
The present invention is a sprinkling device comprising an elongate wobbling distributor head having an open discharge end axially spaced from and structurally connected to a closed base end. The base has a circular hole extending generally axially therethrough. The discharge end comprises at least a sector of an annulus provided on its inner peripheral surface with a plurality of inwardly extending vanes aligned at a slight angle to the axis of the distributor head and terminating short of the center of the annulus, leaving a substantial open area.
BRIEF DESCRIPTION OF THE DRAWING
Understanding of the invention will be enhanced by referring to the accompanying drawing, in which like numbers refer to like parts in the several views and in which;
FIG. 1 is a front elevation view of a sprinkler made in accordance with the invention, shown in partial cross-section to facilitate understanding;
FIG. 2 is a right side elevation view of the sprinkler of FIG. 1;
FIG. 3 is a top view of a portion of the sprinkler of FIG. 1;
FIG. 4 is a top cross-sectional view of the distributor head of the sprinkler of FIG. 1;
FIG. 5 is an end view of the distributor head of FIG. 4;
FIG. 6 is a side cross-sectional view of the distributor head of FIG. 4;
FIGS. 7-10 inclusive show consecutive positions assumed by the distributor head of FIG. 4 during operation;
FIG. 11 1s a partial sectional view of the sprinkler of FIG. 1, showing the sprinkler head in the same position as is indicated in FIG. 7;
FIG. 12 corresponds to FIG. 11 but shows the sprinkler head inithe same position as is indicated in FIG. 9;
FIG. 13 is a front elevational view of a modified form of sprinkler head made in accordance with the invention;
FIG. 14 is a side elevational view of another embodiment of the invention; and
FIG. 15 is a front elevational view of the embodiment shown in FIG. 14.
DETAILED DESCRIPTION
First considering the form of the invention depicted in FIGS. 1-12 inclusive, sprinkler base 10 is connected to support arm 20, at the distal end of which is mounted water distributor head 30. Sprinkler base 10 includes ground-contacting sled 11, which supports housing 12. At one side of housing 12 is internally threaded connection 13, providing a means for conveniently attaching the sprinkler to a hose. At the upper side of housing 12 is internally threaded opening 14, into which is screwed vertically extending externally threaded bearing 27.
Support arm 20 includes tubular vertically extending proximal portion 21, which is rotatably and slidable journaled within bearing 27. The lower end of proximal portion 21 is provided with head 28, which extends over the lower end of bearing 27, washer 29 being interposed between the coextensive surfaces to provide an effective water seal while permitting proximal portion 21 to rotate freely within bearing 27.
At the opposite end of support arm 20 is tubular distal portion 22, desirably extending at an angle of about 30° to the horizontal, thereby (as is well known in the sprinkler industry) permitting a stream of water traversing support arm 20 to attain its maximum horizontal distance. The distal end of distal portion 22 is provided with a restrictions, thereby creating nozzle 25 and limiting the diameter of the water jet 26 which passes through support arm 20 during operation of the sprinkler.
Adjacent the distal end of distal portion 22 are spaced shoulders 24a and 24b, respectively surfaced with rubber washers 36a and 36b, defining neck 23 therebetween. Mounted on neck 23 is elongate water distributor head 30, comprising closed base end 31, having generally centrally disposed hole 32, which is slightly greater in diameter than neck 23, which it loosely surrounds. The thickness of base end 31 is somewhat less than the distance between washers 36a and 36b. Integral with base end 31 is generally tubular wall 33, which extends to annular discharge end 34. The interior peripheral surface of annular end 34 is provided with radially inwardly extending vanes 35, which terminate well short of the center of end 34, leaving an unimpeded central open area. Vanes 35 are generally parallel to each other and extend at a slight angle (e.g., 10°-30° ) to the longitudinal axis of head 30. Preferably the ends of vanes 35 which are closest to base 31 are tapered to permit smoother water flow around them during operation, thereby enhancing the efficiency of water distribution.
When water is supplied to housing 12 by way of connection 13, the pressure lifts support arm 20, firmly seating the lower end of bearing 27 against the upper surface of washer 29. Water jet 26 then emerges from nozzle 25, imparting a wobbling, or precessing, motion to distributor head 30 in a manner best appreciated by referring to FIGS. 7-10, which illustrate the view from beyond discharge end 34 during four successive operational stages of the sprinkler. As shown in FIGS. 7 and 11, the initial position of distributor head 30 is such that jet 26 strikes those vanes 35 that are located at the top portion of end 34. These vanes 35 break up jet 26 into coarse droplets of water that are distributed relatively close to the ground area immediately adjacent end 34. Simultaneously, however, jet 26 lifts discharge end 34 and, because of the angle of vanes 35, imparts an incremental clockwise wobble thereto. As a result, jet 26 now strikes a portion of those vanes 35 located at 3 o'clock, as is shown in FIG. 8. Once again, water jet 26 is diffused by vanes 35, but because only a portion of jet 26 strikes vanes 35, the distance traversed by the stream of droplets is somewhat farther from end 34.
As the action proceeds, the greatest elevation attained by end 34 is shown in FIGS. 9 and 12; here jet 26 is unimpeded and hence attains its greatest distance from end 34. Continuing the wobbling action, the motion of end 34 is such that jet 26 strikes vanes 35 at 9 o'clock, as is shown in FIG. 10. As in FIG. 8, vanes 35 again break water jet 26 into coarse droplets that travel to a distance intermediate discharge end 34 and the maximum distance attained by jet 26 when unimpeded.
During the action just described, base 31 has been restricted in its radial movement, wobbling in a clockwise direction, with the lower surface of base 31 contacting the upper edge of washer 36a while the diametrically opposite surface of base 31 contacts the corresponding diametrically opposite edge of washer 36b is extremely low friction action, the overall path traversed by head 30 thus being essentially conical. The presence of rubber washers 36a and 36b not only serves to reduce noise of operation but also permits a slight clockwise rotational advance of head 30 during operation.
The action of water jet 26 in striking vanes 35 imparts yet another motion to the sprinkler of the invention. If, as is evident in FIG. 7, the maximum engagement of vanes 35 by jet 26 occurs at 12 o'clock, distributor head 30 is accelerated at that point, generating its greatest horizontal force and tending to drive arm 20 in a clockwise direction within bearing 27, so that in due course water is distributed over the entire circular area swept by arm 20. If, on the other hand, the alignment of head 30 with respect to nozzle 25 were such that maximum engagement of vanes 35 by jet 26 occurred at 6 o'clock, the resultant forces would drive arm 20 in a counterclockwise direction. For most efficient clockwise drive, the greatest wobble velocity of head 30 should occur at about 3 o'clock, as shown in FIG. 8; if, however, the greatest wobble velocity occurs at about 1:30, the downward force reduces the frictional drag that occurs along the surfaces of seal 29 and, empirically, achieves most efficient driving of arm 20. As will be readily inferred from the foregoing, for most efficient counterclockwise drive, the greatest wobble velocity should correspondingly occur at about 9 o'clock and 10:30.
It is not absolutely essential that vanes 35 extend around the entire inner periphery of annular discharge end 34. Thus, for example, FIG. 13 shows a modification of distributor head 30 in which vanes 35 extend around only about half of the inner peripheral surface of end 34. Indeed, it has been found that it is possible to achieve satisfactory wobbling and drive if vanes 35 extend over as little as 90° of the peripheral surface. For constructions of this type, however, it is essential that distributor head 30 be permitted to wobble but be prevented from advancing during the wobble operation; unless advance is prevented, it is quite possible to stop the sprinkler with head 30 in a position such that jet 26 will not engage vanes 35 when the sprinkler is turned on again. The manner in which advance of distributor head 30 is prevented will be discussed in more detail in connection with another embodiment of the invention.
Turning now to FIGS. 14 and 15, a further modification of the invention will be observed. In this embodiment, support arm 40 extends in opposite radial directions beyond bearing 27, with water distributor head 50 mounted directly thereover. For convenience in discussion, one end portion of support arm 40 will be designated proximal portion 41 and the opposite end will be designated distal portion 42. At the distal end of distal portion 42 is a restriction, creating nozzle 45 and limiting the diameter of water jet 46 which passes through distal portion 42 during operation of the sprinkler.
Located on proximal portion 41 are spaced shoulders 44a and 44b, defining neck 43 therebetween; shoulders 44a and 44b are respectively covered by rubber washers 56a and 56b, for the same sound-reducing reasons discussed previously. Mounted on neck 43 is elongate water distributor head 50, comprising closed base end 51, having centrally disposed hole 52, slightly greater in diameter than neck 43, which it loosely surrounds. The thickness of base end 51 is somewhat less than the distance between washers 56a and 56b. Integral with base end 51 is open skeletal structure 53, which extends to sector 54 of an annulus, constituting the discharge end of distributor head 50. Mounted along the peripheral interior of sector 54 are vanes 55, all of which are essentially parallel to each other except for vane 55a, at one end of sector 54; vane 55a lies at a significantly greater angle to the longitudinal axis of head 50 than vanes 55. To ensure that distributor head 50 will not advance during operation of the sprinkler, pin 37 extends from the upper side of shoulder 44a, loosely fitting into socket 58 on base 51.
The embodiments of the invention shown in FIGS. 13-15 function in substantially the same manner as the embodiment shown in FIGS. 1-12. In other words, when a jet 26 of water emerges from nozzle 45, it first strikes those vanes 55 which are at the upper end of sector 54, lifting them and imparting a clockwise wobbling motion to distributor head 50. As the wobbling motion proceeds, jet 26 strikes vane 55a, its greater angle to the axis of head 50 imparting a horizontal "kick" to head 50 and driving arm 40 through a counterclockwise rotational path within bearing 27. The same effect could be achieved in various other ways, e.g., by maintaining vane 55a at the same angle as vanes 55 but increasing its radial length.
It will be apparent to readers of the foregoing description that the relationship of the water jet to the vanes has a significant effect on the way the sprinklers of the invention will operate. Appropriate relationships can be achieved by radially offsetting either the distributor head or the nozzle; similarly, the nozzle can be constructed so that the emerging water jet is at an angle to the axis of the distributor head. The direction of rotation of arm 20 can be rendered either clockwise or counterclockwise by appropriately aligning the nozzle and distributor head or by varying the size or angle of vanes 35.
A number of design parameters will readily occur to those skilled in the art. For example, increasing the distance between shoulders 24a and 24b will increase the diameter of the conical base generated by head 30 during wobbling; this in turn will cause water to be distributed over a wider angular area but, because jet 26 may never be fully unimpeded, the distance reached will be less. Similarly, decreasing the weight of distributor head 30 (e.g., by utilizing a more skeletal construction) makes it easier to initiate the wobbling cycle. Wobbling may also be achieved at reduced pressure by increasing the angle at which vanes 35 lie with respect to the longitudinal axis of distributor head 30.
It will, of course, be apparent that sprinklers in accordance with the invention could be so constructed that the water jet was at least partially intercepted by the vanes at all times during the wobbling cycle; such a cdnstruction would, however, sacrifice the size of the area which could be covered. | Lawn sprinkler incorporating a novel water distributing head having a "wobbling" motion. The base of the head is mounted loosely between shoulders near the end of a tubular water-supplying support arm. A water jet emerging from a nozzle at the end of the arm strikes internal vanes at the discharge end of the distributor head to cause the wobbling action. The support arm is journaled within a vertical bearing, and the action of the water jet causes the arm to be driven slowly through a circular path. | 1 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of Korean Patent Application No. 2004-13800 filed Feb. 28, 2004, in the Korean Intellectual Property Office, the entire disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electronic device. More particularly, the present invention relates to a connector opening cover unit of an electronic device, such as a digital video camera (DVC) and a digital still camera (DSC), which covers a connector unit employed for the input of initial set values of the functions, such as zoom center.
2. Description of the Related Art
An electronic device, such as a digital camcorder, converts image information captured through a photographing unit into a digital signal, and writes the digital information in a recording medium, such as a magnetic tape or a non-volatile memory. An automatic-setting function has recently been provided for the convenience of users in setting functions, such as light exposure and focusing. To achieve the automatic-setting function, it is necessary to input a variety of necessary operational data to the control part of the electronic device in the fabrication stage of the electronic device. Accordingly, a connector unit is used for the data input in the fabrication stage. However, this connector unit is not to be accessed by general users, and therefore, it is externally covered after fabrication of the electronic device to limit the access of general users.
FIG. 1 illustrates one example of fastening a connector unit cover to cover the connector unit of a digital camcorder. As shown, a digital camcorder housing 1 has a connector opening 2 that is integrally formed in the body thereof, and through which a connector unit 3 for the data input is exposed to the outside. The connector unit 3 is connected with predetermined data, and therefore received various set values of the digital camcorder.
The connector opening 2 exposing the connector unit 3 to the outside has to be covered to prevent access by general users when all the set values are transmitted to the digital camcorder. A connector opening cover 4 is provided to correspond to the connector opening 2 . The connector opening cover 4 is fastened to the digital camera housing 1 by a locking projection 4 ′ formed on a side, and a screw 5 fastened for the prevention of unintended separation.
According to the construction as described above, because the connector opening cover 4 has to be fastened to the connector opening 2 including therein the connector unit 3 by separate fastening members, such as screws 5 , the volume of the product increases, and the number of parts to be fabricated also increases. Additionally, due to the requirement for the separate fastening members, such as screws 5 , the price of the product also increases.
Therefore, a need exists for an electronic device having a structurally improved connector opening cover unit that does not require additional tools and fasteners to open and close the cover unit.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide a connector opening cover unit of an electronic device that is structurally improved and capable of covering a connector unit for the input of basic set values during the fabrication stage, without requiring separate fastening members.
A connector opening cover unit of an electronic device has a connector opening provided in abutment with a device accommodating opening that is selectably openable by the user. A first cover opens and closes the device accommodating opening and a second cover to open and close the connector opening. The first and the second covers are complimentarily locked with each other. The second cover utilizes the space of the device accommodating opening to slide, and is preferably slid to engagement with the first cover along a guide that is protruded from the inner boundary of the connector opening.
The above aspects and other features of the present invention may substantially be achieved by providing a connector opening cover unit that covers a connector opening of an electronic device housing to prevent externally exposing a connector unit inside the electronic device housing. The connector opening cover unit includes a device accommodating opening that may be selectably opened and closed by a user. A first cover to open and close the device accommodating opening. A connector opening formed in abutment with the device accommodating opening, and having the connector unit received therein. A second cover to open and close the connector opening. The first and the second covers are complimentarily locked with each other.
The second cover may include a connector opening cover body. A sliding protrusion is formed on both sides of the connector opening cover body to slide the second cover along the connector opening. A guide groove prevents the connector opening cover body from sinking into the connector opening. A first locking tab protrudes from an end of the connector opening cover body in the lengthwise direction. A second locking tab protrudes in opposite relation with respect to the connector opening of the connector opening cover body to restrict the sliding movement of the first cover.
The first locking tab may be seated in a first receiving groove that is formed in the inner boundary of the connector opening corresponding to the first locking tab.
The second locking tab may be seated in a second receiving groove that is formed in the electronic device housing corresponding to the second locking tab.
The connector opening cover body may be slid along a space of the device accommodating opening to cover the connector opening.
The device accommodating opening may be a secondary battery receiving opening to supply secondary power to the electronic device.
Other objects, advantages and salient features of the invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The above aspects and features of the present invention will be more apparent by describing certain embodiments of the present invention with reference to the accompanying drawings, in which:
FIG. 1 is a perspective view illustrating a conventional connector opening cover being fastened to an electronic device according to conventional art;
FIG. 2 is a perspective view of a connector opening cover unit having first and second covers according to an embodiment of the present invention;
FIG. 3 is a perspective view of the first and second covers of FIG. 2 before fastening;
FIG. 4 is a perspective view of the second cover of FIG. 2 ;
FIG. 5 is a plan view of the complementary locking of the connector opening cover of FIG. 2 ; and
FIGS. 6 and 7 are plan views of the first cover open and the second cover sliding.
Throughout the drawings, like reference numerals will be understood to refer to like parts, components and structures.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Certain embodiments of the present invention will be described in greater detail with reference to the accompanying drawings.
The matters defined in the description, such as a detailed construction and elements thereof, are provided to assist in a comprehensive understanding of exemplary embodiments of the invention. Thus, it is apparent that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the invention. Also, descriptions of well-known functions or constructions are omitted for conciseness and clarity.
FIGS. 2 and 3 show a connector opening cover being assembled in accordance with an exemplary embodiment of the present invention.
More specifically, FIGS. 2 and 3 show the electronic device housing in which a rechargeable battery mounting unit 10 is provided to supply power to the electronic device, such as a camcorder. The rechargeable battery mounting unit 10 has a secondary battery receiving unit 10 a in which a secondary battery (not shown) is mounted for the maintenance of basic information of the electronic device. The secondary battery receiving unit 10 a may be opened and closed by a first cover 20 .
The first cover 20 includes a cover body 21 aligned with the open side of the secondary battery receiving unit 10 a , a flexible band 22 , and a locking tab 23 ( FIG. 6 ) engaged to an end of the cover body 21 . The flexible band 22 firmly holds the cover body 12 to the rechargeable battery mounting unit 10 , and when the cover body 21 is in open state, acts as a pivot. More specifically, because the flexible band 22 is bent by its own flexibility and acts as a pivot for the movement of the first cover 20 . Thus, the freedom of opening movement of the first cover 20 is increased, and as a result, the user's convenience in opening the first cover 20 is increased. The locking tab 23 hooks the end of the second cover 100 , which will be described below. The locking tab 23 may be preferably formed on a certain side of the first cover 20 that meets with the second cover 100 . Additionally, an end of the locking tab 23 may preferably be rounded so that less force is required to release the first cover 20 from the second cover 100 .
A connector opening 10 b is formed in communication with the secondary battery receiving unit 10 a, and selectively exposes the connector unit 40 , which is provided for the input of basic set values of respective components of the electronic device. The connector unit 40 is provided for the transfer of basic set values to the electronic device during the fabrication process. Therefore, the connector unit 40 is covered upon completion of the fabrication to limit access by general users. As shown in FIGS. 2 through 7 , the second cover 100 has a configuration corresponding to the connector opening 10 b to fittingly cover the connector opening 10 b.
Specifically referring to FIG. 4 , the second cover 100 includes a connector opening cover body 110 , a sliding protrusion 120 , a guide groove 130 , a first locking tab 140 , a handgrip recess 150 and a second locking tab 160 .
The connector opening cover body 110 has a configuration corresponding to the connector opening 10 b , and may preferably have the thickness corresponding to that of the first cover 20 . Additionally, as shown in FIG. 5 , the first cover 20 and the connector opening cover body 110 are formed for complimentary fitting with each other.
The sliding protrusion 120 is supported by one end on the guiding tab 11 that protrudes from the inner boundary of the connector opening 10 b , and slides along the sliding groove 12 that is formed along the inner boundary of the connector opening 10 b . In one preferable example, the sliding groove 12 and the sliding protrusion 120 may be formed in respectively complimentary configurations.
The guide groove 130 is formed in a configuration complimentary with the guide 11 , and while the sliding protrusion 120 is slid along the sliding groove 12 , the guiding tab 11 is slid along the guide groove 130 .
Accordingly, the sliding protrusion 120 , the sliding groove 12 , the guide groove 130 and the guiding tab 11 act as a rail that guides the sliding movement of the second cover 100 , and also prevents the unintended movement of the second cover 100 , such as sinking into or moving out of the housing.
first locking tab 140 prevents unintended release of the second cover 100 , and more firmly maintains the locking status of the second cover. In one preferred example, as shown in FIGS. 3 and 4 , a plurality of the first locking tabs 140 may be provided at the lower side of the connector opening cover body 110 facing in a downward direction. In this example, first locking tab receiving holes 14 are formed in the inner boundary of the connector opening 10 b in locations corresponding to the first locking tabs 140 for engagement with the first locking tabs 140 .
A handgrip recess 150 is provided for the user to grip on an end of the first cover 20 when releasing the locking tab 23 to open the first cover 20 . The handgrip recess 150 is located at an end of the connector opening cover 110 . In one preferred example, as shown in FIG. 3 , the handgrip recess 150 is formed on an end of the connector opening cover body 110 that contacts the first cover 20 .
The second locking tab 160 further prevents the second cover 100 from sliding. More specifically, the second locking tab 160 restricts the second cover 100 from sliding when the first cover 20 is opened such that the second cover 100 is slid only when a certain degree of force is exerted by the user. Referring to FIG. 4 , the second locking tab 160 may be formed on a side opposing the handgrip recess 150 . A second locking tab receiving hole 13 is formed in a corresponding location of the frame defining the rechargeable battery mounting unit 10 to receive the second locking tab 160 .
Attaching and detaching the second cover 100 according to one embodiment of the present invention will be described below with reference to accompanying drawings.
Referring to FIG. 3 , the rechargeable battery mounting unit 10 includes a secondary battery receiving unit 10 a to receive a secondary battery therein and a connector opening 10 b to externally expose the connector unit 40 , which is provided for the input of basic set values of the electronic device. The secondary battery receiving unit 10 a is adjacent the connector opening 10 b . The secondary battery receiving unit 10 a and the connector opening 10 b are covered by separate cover members. In this example, the secondary battery receiving unit 10 a is covered by the first cover 20 , and the connector opening 10 b is covered by the second cover 100 .
Referring to FIG. 5 , the first cover 20 completely covers the secondary battery receiving unit 10 a formed in the rechargeable battery mounting unit 10 , in complimentary engagement with the second cover 100 . To open the first cover 20 , the user holds the first cover 20 with a finger on the handgrip recess 150 , and lifts up the first cover 20 . Accordingly, the first cover 20 is opened upward as the locking tab 23 is released from the end of the second cover 100 , as shown in FIG. 6 .
When the first cover 20 is opened, the second cover 100 , which is slidably fitted to the lower side of the first cover 20 , may be slid upward and removed. More specifically, as shown in FIG. 5 , the second cover 100 is restricted from moving upward by the end of the first cover 20 while the first cover 20 is in closed position, which covers the secondary battery receiving unit 10 a . When the first cover 20 is opened, as shown in FIG. 6 , the second cover 100 is released from the locked position and therefore, becomes upwardly slidable.
Accordingly, to remove the second cover 100 the first cover 20 is opened, and with the secondary battery receiving unit 10 a in the opened position, the second cover 100 is slid in the direction indicated by an arrow in FIG. 6 , thereby separating the second cover from the connector opening 10 b as shown in FIG. 7 .
Attaching the second cover 100 to cover the connector opening 10 b is performed substantially reversing the above described process. That is, with the first cover 20 in the opened position, the second cover 100 is positioned toward the secondary battery receiving unit 10 a as shown in FIG. 7 . The second cover 100 is then moved toward the end of the connector opening 10 b , that is, to the closed position so that the sliding protrusion 120 may be slid along the sliding groove 12 . The second cover 100 is until the sliding protrusion 120 is proximal the upper side of the guiding tab 11 and the guiding tab 11 is seated in the guide groove 130 of the second cover 100 .
When the second cover 100 is slid to the closed position of the connector opening 10 b , the first locking tab 140 and the second locking tab 160 are respectively seated in the corresponding receiving holes 14 and 13 , and as a result, the second cover 100 is fixed in the closed position.
With the connector opening cover unit as described above in a few exemplary embodiments of the present invention, the first and the second covers 20 and 100 are complimentarily locked with each other, and therefore, the inconvenience of using separate locking members or separate tools, such as a driver to fix the second cover 100 , is prevented. Additionally, breakage of a locking unit due to repeatedly opening and closing the second cover 100 is prevented.
According to the present invention, a connector opening cover unit includes a first cover to open and close the secondary battery receiving unit and a second cover to open and close the connector opening, and the first and the second covers are complimentarily engaged with each other. Because separate fastening means is not required to cover the connector opening according to exemplary embodiments of the present invention, the number of fabricated parts is reduced, and the manufacturing costs are greatly reduced.
The foregoing embodiment and advantages are merely exemplary and are not to be construed as limiting the present invention. The present teaching may be readily applied to other types of apparatuses. Also, the description of the embodiments of the present invention is intended to be illustrative, and not to limit the scope of the claims, and many alternatives, modifications, and variations will be apparent to those skilled in the art. | A connector opening cover unit selectively covers a connector opening to prevent exposing a connector unit inside an electronic device housing. A connector opening is adjacent a device accommodating opening that is selectively openable by a user. A first cover opens and closes the device accommodating opening. A second cover opens and closes the connector opening. The first and second covers are complimentarily locked with each other. | 7 |
This is a continuation of co-pending application Ser. No. 07/803,091 filed on Dec. 5, 1991, and now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a multi-functional therapeutic workstation which can simulate a multitude of job tasks. The workstation is ideally suited for patients recovery from traumatic hand injury, upper extremity injury, back or lower extremity injury, traumatic brain injury or other neurological disorders. More specifically, the multi-functional workstation kit consists of five panel designs with right angle brackets, nuts and bolts that can be assembled into several modules. Hand tools must be used to assemble most of the nuts, bolts, washers and screws.
2. Description of the Related Art
There exists a need for a therapeutic device for patients that have suffered traumatic injuries or illness and that have a need to exercise the healing limbs or neurological pathways so that the patient may be rehabilitated and resume normal activities. These injuries may, for instance, include traumatic hand injury, upper extremity injury, back or lower extremity injury, traumatic brain injury or other neurological and medical disorders.
In an earlier effort to meet this need, U.S. Pat. No. 4,795,351 describes a method and device in which the patient is required to perform manual operations within a visually obscured enclosure. Partitions are provided within the enclosure to simulate the performance of mechanical operations such as the placing and tightening of nuts on bolts inside the enclosure. However, this patent only addresses fine motor skills such as placing nuts on bolts and does not address the rehabilitation of those muscles which control other ranges of motions. Indeed, the device is limited to fine motor control of these muscles of the hand.
What is needed is a device that is versatile and that can be used to rehabilitate patients suffering from a wide variety of impairments. For instance, the device should be capable of inducing the patient to exercise the complete upper extremity range of motion, should encourage muscle strengthening and muscle endurance while also providing tool handling/prehension tasks with either low or high torque activity. Further, the device should allow the manipulation of tools to exercise those muscles that control fine motor coordination as well as gross motor coordination. It is also desirable that the device could be juxtaposed relative to the patient so as to exercise sitting and standing tolerance, kneeling, bending and squatting tolerance, as well as supine, side lying or overhead work tolerance. Furthermore, the device should also be suitable for simulation of working in a confined space and should exercise vertical, horizontal and diagonal reaching tolerances. It is furthermore desirable that the therapeutic device should not only address physical activities but should also stimulate cognitive, perceptual motor skills such as following directions, problem solving and abstract thinking, redevelopment of organizational skills, extending attention span, replication of detail and design copy, understanding spatial relationships, discriminating between the left side and the right side, visual sequencing, motor planning, sorting and sequencing of tasks, and the like. Therefore, it is desirable that the therapeutic device be able to rehabilitate both physical muscular activity as well as neurological activities, such as cognitive perceptual motor skills, and should simulate job tasks.
SUMMARY OF THE INVENTION
The invention provides a multi-functional workstation kit which comprises five basic panels with right angle brackets, bolts and nuts that can be assembled into several positions. The assembly of these panels into various modules, provides muscular exercise therapy, range of motion and job simulation while at the same time stimulating cognitive perceptual motor skills. The panels include left, middle and right panels, top and bottom panels and shelves. Thus, there are a total of five different panel designs.
During therapy, an objective is set for the patient which requires the construction of a module which includes the fastening together of at least two of these panels. In more complex exercises, the patient will be required to assemble a larger number of panels, depending upon the motor and cognitive skills that the therapist determines should be exercised.
The panels are each of a specific design, as shown in FIGS. 1-5, and are generally clamped, bolted or screwed together with right angle brackets at the corners. The right angle brackets are designed so that when two panels are bolted together at right angles to each other, the right angle brackets at the corners will rest one on top of the other and the upper surface of the right angle bracket will remain flush with the upper or lower edges of the panels as shown in FIG. 6A.
The panels may be fabricated of sheet metal, or any other suitable, preferably lightweight, thin material. For instance, the panels may be fabricated from an organic polymeric composition or a composite of an organic polymer. The panels are each uniquely designed with the exception that the top panel is a mirror image of the bottom panel. The apertures shown in the left and right panels are intended as hand grips so that, in certain modules, the patient may be readily able to lift and manipulate the module. The middle panel is supplied with apertures through which a patient may extend his hand and arm for manipulating washers, tools, nuts and bolts inside or outside the assembly. While only three apertures are shown, it is understood that apertures of different shapes and sizes will also suffice to permit the performance of this function.
The above-described multi-functional workstation can simulate a multitude of job tasks and can meet several treatment objectives, depending upon the module that the patient is required to construct and the patient's position relative to the work pieces during the construction. Further, depending upon the complexity of the module that the patient is required to construct, the workstation also exercises the patient's cognitive skills. Therefore, the invention multi-functional workstation is able to provide rehabilitative therapy for both physical and neurological trauma or illness.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a right-hand panel with right angle brackets at each corner and three pairs of struts into which the edge of a shelf may slide.
FIG. 2 is a middle panel with right angle brackets at each corner and three apertures through which an individual may insert a hand or arm.
FIG. 3 is a left-hand panel with right angle brackets at each end and three pairs of struts into which the edges of a shelf may slide.
FIG. 4 is a top or bottom panel.
FIG. 5 is a shelf panel.
FIG. 5A is a shelf panel.
FIG. 6 shows a middle panel attached to a left-hand panel with right angle brackets.
FIG. 6A is an enlarged representation of a right angle bracket at one of the corners of FIG. 6.
FIG. 7 shows a middle panel bolted to a left-hand panel and indicates how the top panel may be fastened to the middle and left panels.
FIG. 8 shows an assembly including a middle panel, left and right panels, and a top panel.
FIG. 9 is an assembly including middle, left, right, top and bottom panels.
FIG. 10 is the assembled workstation of FIG. 9 including two shelves in the "standard assembly position".
FIG. 11 is a "two panel position" showing a top and bottom panel fastened with right angle brackets.
FIG. 12 is a "vertical 45° angle assembly" showing a vertical middle panel mounted at 45° across a bottom panel.
FIG. 13 is a "perpendicular assembly," showing a left-hand panel mounted perpendicular to a bottom panel.
FIG. 14 is a "three panel horizontal assembly" showing end panels, top and bottom panels, centered and attached at right angles to each end of a horizontal left panel.
FIG. 15 is a "wide overhead assembly" showing a middle panel with a right panel attached a right angles at one end and a left panel attached at right angles at the other end to form an inverted U-shape.
FIG. 16 is a "45° angle assembly" showing two end panels, top and bottom panels, to each of which is attached one end of a middle panel, at 45°.
FIG. 17 is the 45° angle assembly of FIG. 16 with a left- or right-hand panel mounted horizontally above the angled middle panel.
FIG. 18 is a "parallel assembly" showing two end panels, top and bottom panels, the upper ends of which are attached to the ends of a left or right panel while the centers are attached to a middle panel to form an A-shaped structure.
FIG. 19 is a "perpendicular assembly," which is similar to the middle panel assembly of FIG. 17 except that the middle panel is not mounted at 45° but is mounted perpendicularly.
FIG. 20 is the "perpendicular assembly" of FIG. 19 with a panel mounted onto the free ends of the top and bottom panels.
FIG. 21 is the A-shaped parallel assembly of FIG. 18 with a panel mounted to the free ends of the top and bottom end panels.
FIG. 22 is the 45° assembly of FIG. 17 with a panel attached to the free ends of the top or bottom end panels.
FIG. 23 is a "three person workstation" showing five panels attached at right angles to each other with right angle brackets to form an S-shape.
FIG. 24 is the S-shaped structure of FIG. 23 in a vertical position.
FIG. 25 is a "single extension assembly" for extended trunk positions, including a horizontal middle panel to which is attached at each end top and bottom panels, and to which is further attached, on the top side, a right- or left-hand panel to form an enclosed shape. A left- or right-hand panel is then attached at right angles to one of the end panels.
FIG. 26 is a "double extension assembly" wherein the middle panel of the single extension assembly of FIG. 25 is relocated to a position perpendicular to and at the center of the top or bottom panel.
FIG. 27 is an assembly for exercising in the overhead shoulder position.
FIG. 28 is an assembly for exercising in the kneeling or squatting position.
FIG. 29 is an assembly for exercising in the long overhead position, position 1.
FIG. 30 is an assembly for exercising in the long supine or side lying overhead position of FIG. 29 but with the panels interchanged.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Assembly of the invention multi-functional workstation kit provides a versatile therapeutic activity which can simulate multiple job tasks. The workstation is ideally suited for patients recovering from traumatic hand injury, upper extremity injury, back or lower extremity injury, traumatic brain injury, or other neurological or physiological disorders. The use of this multi-functional workstation kit can be of benefit to hand rehabilitation centers, orthopedic rehabilitation departments, work hardening centers, vocational rehab or work training centers, head trauma or neurological rehabilitation centers, and mental health facilities.
The multi-functional workstation kit is designed for use as a therapeutic training activity. Furthermore, it provides an outlet for creative expression that caters to many occupations including, but not limited to, air conditioning repair work, aircraft mechanics, assembly workers, automotive mechanics, carpentry, electrical work, electronic assembly and repair work, routine maintenance work, machine work, masonry and concrete work, plumbing, small engine repair, sheet metal work, and the like.
In assembling the workstation into one of many arrangements or modules, the following physical activities can be addressed: complete upper extremity range of motion; whole body range of motion; muscle strengthening; muscle endurance improvement; tool handling and prehension tasks with low or high torque activity; fine motor coordination; gross motor coordination; desensitization and sensory input; sitting and standing tolerance; kneeling, bending and squatting tolerance; supine or side lying tolerance; overhead work tolerance; confined work space tolerance; and vertical, horizontal and diagonal reaching tolerance. The workstation also provides a stimulating medium for developing the following cognitive perceptual motor skills: following directions, problem solving and abstract thinking, organizational skill development, attention span development, replication of detail and copying of designs, understanding spatial relationships, left and right discrimination, positioning in space perception, visual sequencing, motor planning, form and shape consistency recognition, sorting and sequencing tasks, depth perception, and the like.
The multi-functional workstation consists of five panels, with right angle brackets, nuts, washers, bolts, shelves and hand tools, and can be assembled into several modules or "positions." Since each patient's treatment program will differ, the modules to be constructed and the juxtaposition of the module relative to the patient will vary.
The basic panels are shown in FIGS. 1 through 5. FIG. 1 shows a left-hand side panel 10 with a plurality of holes drove through the panel. Further, the left-hand panel has an aperture 12 for holding or grasping. The middle panel 14 is also supplied with a plurality of holes for receiving bolts and has, in addition, several apertures through which a patient may insert his or her hand or arm. These apertures are shown as 16, 18 and 20. It will be understood that more or fewer apertures may be used and that the size and shape of the apertures may vary, as long as patient is able to insert his or her hand or arm through the aperture. A right-hand panel 22 is shown in FIG. 1 with hand-grip 24. This panel is also supplied with several holes for receiving bolts. FIG. 4 shows a top or bottom panel 26 which is square in shape and which is also supplied with holes for receiving bolts. Shelving for use in constructing some of the modules is shown in FIG. 5 and FIG. 5A. The shelf 28 is typically supplied with an aperture 30 through which a patient may extend an arm for manipulating nuts, bolts and the like. Moreover, a section may be removed from one edge 32 of the shelf to provide a gap through which a patient may insert his hand or arm once the shelf is in place.
In order to better understand the functioning and purpose of the multi-functional workstation kit, the construction of various modules and the purpose for their construction will be explained. It will be understood that the usefulness of the invention is not limited to those assembled modules which are described herein.
The "standard position" or standard module relates to the construction of a module which incorporates the whole body range of motion. This position also addresses gross and fine motor skills in a confined work space through the assembly of nuts, bolts and washers, with or without the use of hand tools. As an optional activity, string may be threaded through panels to simulate wiring. To assemble this module, the following cognitive skills will be used: a higher level of attention span, ability to follow directions, replication of details, problem solving, and left and right discrimination. The module may be constructed on a table top while the patient is standing or sitting. When the working kit is placed on the floor, the patient can simulate such working conditions as kneeling or squatting, lying on the side or in a supine position for overhead tasks. The unique feature of this module's construction is the amount of workspace confinement, which can be controlled by removing or adding shelves. This module's construction is illustrated in FIGS. 6-10 where a series of panels are bolted together to form the standard assembly module. As may be seen from FIGS. 6 and 6A, the modules are constructed by joining together separate panels with right angle brackets 34. These right angle brackets 34 are designed so that, when the panels are placed together, the overlapping right angle brackets 34 will rest one on top of the other so that the upper surface of the right angle brackets is flush with the edges of the panels. This is illustrated, for example, in FIG. 6A.
FIGS. 7, 8 and 9 show the progressive development of the standard module and FIG. 10 shows the complete module. Depending upon the degree of confinement of activity required, the number of shelves 28 that slide into shelf fittings 36 may be varied. FIG. 10 shows two shelves but has a provisional third shelf bracket. Once the patient has assembled the module of FIG. 10, he may then be assigned the task of attaching nuts, bolts and washers to any of the panels. He may also pass wires or threads through the holes in a preselected pattern to further develop fine motor skills.
A more simple, beginning assembly, for someone with limited attention span and problem solving skills, is a two-panel embodiment. In the first of these, the "right angle assembly" shown in FIG. 11, two panels are attached at right angles. This simple assembly requires a fair degree of strength and endurance. In two other embodiments, the perpendicular and vertical 45° angle assemblies, shown in FIGS. 12 and 13, the assembly exercises visual directionality, crossing the midline and spatial relationship skills.
There are at least 3 "three-panel positions," including the wide overhead assembly shown in FIG. 15, the horizontal assembly shown in FIG. 14, and the 45° angle assembly shown in FIG. 16. The wide overhead assembly promotes the whole range of body motion, overhead reaching and muscle endurance. While this assembly is simple, it requires basic problem solving skills and design application skills. The patient can work on this assembly in supine, side lying, kneeling, or squatting positions. In the horizontal assembly, the patient concentrates on the upper extremity range of motion, especially shoulder rotation, and pronation or supination. The assembly incorporates design replication, recognition of spatial relationships, and crossing the midline. This module is best assembled on a table top. However, the kit could also be placed on the floor to provide a confined work space while the patient uses body positions, such as side-lying or lying supine, while constructing the assembly. Finally, the 45° angle assembly provides the patient with an opportunity for shoulder and trunk motions while concentration on all wrist motions. This assembly is cognitively stimulating and incorporates attention to detail, design replication, and also allows for a visually occluded work space. The assembly is best utilized if placed on a table top.
There are at least three embodiments of a "double obstacle position." These include the middle panel module shown in FIG. 17, the parallel assembly module shown in FIG. 18, and the perpendicular assembly shown in FIG. 19. The parallel assembly provides the patient with the opportunity for gross motor coordination and internal and external shoulder rotation. It also provides lateral trunk motion and the opportunity to improve balance. The patient can be assigned the task of attaching nuts, bolts and washers to any of the panels. As an option, thread or wire may be strung through the panels to simulate wiring tasks using fine motor coordination. The assembly requires the use of depth perception and the exercise of spatial relationship skills. The patient could assemble this module horizontally on a table, sitting or standing, or the kit may be placed on the floor so that the patient may assemble it in the supine or side lying body positions. In the 45° angle assembly, the patient is provided with the opportunity for complete upper extremity range of motion and all wrist motions. Assembly incorporates visual sequencing, crossing the midline, positioning in space, motor planning, and replication of details. Assembly is a relatively cognitively challenging activity. The workstation kit should be positioned on a table top for assembly by a patient in either the sitting or standing positions. In the perpendicular assembly, the ranges of wrist motions are emphasized. This position incorporates visual sequencing, crossing the midline, motor planning, and replication of details, and is intended to be cognitively challenging.
The invention multi-function workstation kit may also be assembled into several "triple obstacle positions." These include the perpendicular assembly of FIG. 20, the parallel assembly of FIG. 21 and the 45° angle assembly of FIG. 22. Typically, the workstation kit is placed on a table top and the patient assembles the module on the table top as shown. Assembly of the perpendicular module of FIG. 20 requires the whole range of body motions, extreme wrist range of motions, shoulder and overhead activity, and diagonal reaching. Cognitively, assembly requires crossing the midline as well as replication of detail, working within a visually occluded work space, and the exercise of visual directionality. In the parallel assembly of FIG. 21, the patient exercises gross motor coordination, vertical reaching, and works within a confined work space. Assembly also maximizes upper extremity endurance. The patient can be assigned the task of attaching nuts, bolts and washers to any of the panels. String may be threaded through the panels to simulate wiring tasks for the exercise of fine motor skills. Assembly requires organizational skills, the capability to replicate details, recognition of spatial relationships, and spatial depth perception. Typically, the assembly is carried out on a table top while the patient is sitting or standing. However, assembly can also be performed on the floor while the patient is in a kneeling or squatting position. The module of FIG. 22 provides for the full range of body motion, with an emphasis on prehension and tool handling within a limited work space. The assembly is challenging and stimulating requiring depth perception, motor planning, and spatial perception. Assembly may be carried out on a table top.
The invention multi-function workstation kit may also be assembled into a "three person workstation." These three person workstations are illustrated in FIGS. 23 and 24. Their assembly utilizes trunk rotation while standing. They also require the exercise of gross motor skills, tool handling with either low or high torque. The assembly demands a high ability to replicate detail, discriminate between left and right, and spatial depth perception. These workstations should be assembled vertically, or horizontally, on a table top.
The workstation may also be assembled into at least two "extended trunk positions." The single extension assembly or module is shown in FIG. 25; the double extension assembly in FIG. 26. Both of these extension assemblies require the total range of body motion with full trunk rotation and reaching. Assembly may be carried out while the patient is standing, sitting, squatting, lying on its side or supine. Horizontal and diagonal reaching exercises can also be achieved. The assemblies are cognitively challenging and require complex motor planning and problem solving skills. Left and right discrimination and replication of details are also necessary. The single extension assembly is best utilized on a table top, but could be constructed while lying on the side on the floor. Construction of the double extension assembly may be carried out on a table top by one or more patients. The module may also be placed on the floor so that patients may crawl into the open areas which allow for activities such as extreme trunk rotation and reaching.
FIG. 27 shows an assembly, "the overhead shoulder position," which incorporates the whole body range of motion, improving muscle endurance and strengthening of muscles, as well as reaching and bending, during construction. The patient may be standing, sitting, kneeling or squatting during assembly. Assembly requires a high level of abstract thinking, organizational skills, and a high level of replication of detail. Similarly, the kneeling or squatting position of FIG. 28 also requires a high range of physical activities, cognitive and perceptional motor skills and may be assembled in the standing, sitting, kneeling or squatting positions.
Finally, the long overhead positions shown in FIGS. 29 and 30 promote the whole range of body motion during construction. These include reaching into all planes of motion, muscle endurance and strengthening. Furthermore, the module can provide confined work space simulation and assists in developing overhead work tolerance. Assembly requires a high level of attention span, visual skill, depth perception, sequencing of tasks, and abstract thinking. When assembled on a table top, it is possible for two or more patients to work simultaneously. When placed on the floor, the assembly allows the patient to crawl inside and work in supine or side lying body positions.
Having described the invention above, various modifications of the techniques, procedures, material and equipment will be apparent to those in the art. It is intended that all such variations within the scope and spirit of the appended claims be embraced thereby. | A multi-functional therapeutic workstation which can simulate a multitude of job tasks. The workstation kit includes five panel designs, right angled elbows, nuts and bolts, and can be assembled into a variety of modules requiring the exercise of varying levels of cognitive and motor skills. Depending upon the position of the patient relative to the workstation kit, and the module that the patient is required to construct, the assembly rehabilitates both muscles as well as neurological pathways. | 6 |
[0001] This application is a continuation of U.S. patent application Ser. No. 12/720,857, filed Mar. 10, 2010 which claims the benefit of U.S. patent application Ser. No. 11/419,829, filed May 23, 2006, which claims the benefit of U.S. patent application Ser. No. 10/459,849, filed Jun. 12, 2003, which claims the benefit of U.S. Provisional Application No. 60/388,049, filed Jun. 12, 2002, all of which are incorporated herein by reference in their entirety.
FIELD
[0002] The present inventive subject matter relates to the art of authentication. It finds particular application in conjunction with facilitating the authentication of an individual to conduct a secure transaction with a credit or debit card or other payment instrument or payment means over a communications network, e.g., the Internet, and it will be described with particular reference thereto. It is to be appreciated, however, that the present inventive subject matter is also amenable to other like applications.
BACKGROUND
[0003] Internet commerce, or e-commerce as it is otherwise known, relates to the buying and selling of products and services between consumers and merchants over the Internet or other like transactional exchanges of information. The convenience of shopping over the Internet has sparked considerable interest in e-commerce on behalf of both consumers and merchants. Internet sales, or like transactions, have been typically carried out using standard credit cards such as Visa®, MasterCard®, Discover®, American Express®, or the like, or standard debit cards, i.e., check cards or automated teller machine (ATM) cards which directly access funds from an associated deposit account or other bank account. Other payment methods have also been developed for making payments in connection with e-commerce transactions. For example, these include PayPal®, Bill Me Later®, Secure eBill, Western Union, and the like.
[0004] While widely used for more traditional face-to-face transactions, use of standard cards in connection with e-commerce presents certain difficulties, including difficulties concerning authentication or positive identification of the cardholder. For example, maintaining consumer confidence in security has become difficult with increased reports of fraud. The resulting apprehension is also fueled by consumer uncertainty of the reputation or integrity of a merchant with whom the consumer is dealing. Questionable security of the consumer's card information or other personal information typically submitted along with a traditional e-commerce transaction (e.g., address, card number, phone number, etc.) serves to increase apprehension even more. Additionally, cardholders, merchants and financial institutions are all concerned about safeguarding against fraudulent or otherwise unauthorized transactions. Similarly, other payments methods are concerned with security.
[0005] Accordingly, various payment networks have implemented initiatives or programs aimed at safeguarding against fraud. For example, Visa® and MasterCard® both support authentication initiatives whereby a cardholder is authenticated by the bank or financial institution issuing the card, i.e., the issuing bank. FIG. 1 , illustrates one such exemplary authentication initiative. As shown in this example, a consumer/cardholder 10 , e.g., employing a suitable web browser or the like, is making an on-line purchase, e.g., over the Internet, from a merchant 20 . As is known in the art, the illustrated back-end payment processing chain includes an optional payment gateway 30 , the merchant's financial institution or acquiring bank 32 , the credit card network 34 and the issuing bank 36 .
[0006] At a point of checkout, the consumer 10 selects an appropriate payment method based on the initiatives supported by the merchant 20 . At this point, the consumer fills out the on-line checkout form including a payment option, card number, expiration date, etc. Based on the payment information, the merchant 20 , via a plug-in 22 installed on their server, passes a verify enrollment request (VEReq) message to a directory 38 on a server, e.g., suitably operated by the credit card network 34 . The directory 38 includes a database associating participating merchants with their acquiring banks and a database associating card number ranges with locations or addresses, e.g., universal resource locator (URL) addresses, of issuing banks' authentication servers, e.g., the authentication server 40 for issuing bank 36 . The VEReq message is a request to verify the enrollment of the card in the authentication program, and it contains the card number provided by the consumer 10 .
[0007] Based on the card number range stored within the directory, the VEReq message will be sent to the appropriate URL address for the server 40 which returns to the merchant 20 via the directory 38 a response thereto, i.e., a verify enrollment response (VERes). That is to say, the server 40 will verify the enrollment status of the card and respond with a VERes message to the directory 38 which is then passed back to the merchant's plug-in component 22 .
[0008] Based on the VERes message (i.e., if positive), the merchant plug-in component 22 will redirect the cardholder's browser to the server 40 by passing it a payer authentication request (PAReq) message generated by the merchant's plug-in component 22 . The consumer 10 then completes an authentication process directly with the server 40 . The authentication server 40 authenticates the consumer/cardholder 10 and responds to the merchant 20 with a payer authentication response (PARes) message including a digital signature. The merchant's plug-in component 22 validates the digital signature of the PARes and extracts the authentication status and other specified data that is to be used by the merchant 20 during the payment authorization process carried out via the back-end payment processing chain. For example, the merchant 20 sends an authorization/sale transaction to their payment gateway 30 along with the data elements received from the PARes. The payment gateway 30 routes the data to the acquiring bank 32 based on the acquirer's specification. The acquiring bank 32 then sends the data via the appropriate credit card network 34 to the issuing bank 36 for settlement.
[0009] When using authentication initiatives such as the aforementioned example, the credit card network often ensures participating merchants that fraudulent transactions and other charge backs, as they are known in the art, will not be the merchants' responsibility provided the specified protocols have been followed. However, there are considerable burdens placed upon the merchants to participate in the authentication initiatives. For example, typical installation of the merchant plug-in can be overly burdensome using up resources, i.e., computing power, memory, data storage capacity, etc., the merchant would otherwise prefer to devote to other tasks. Often, the plug-in component can be extremely large and/or cumbersome to implement on the merchant's server. Moreover, for a merchant that participates in a plurality of such authentication programs for multiple credit card networks, the burden can be that much more, i.e., requiring a separate plug-in component for each individual authentication initiative they wish to support, especially considering that each credit card network may have its own particular protocols, data fields that are employed in the respective messages, specific data format requirements, etc.
[0010] Further, the merchants are responsible for remaining current with initiative protocols that can change periodically. That is to say, as the authentication protocols are updated and/or changed by the respective credit card networks, the merchants are likewise responsible for updating and/or changing their plug-in components to reflect those update and/or changes being mandated by the credit card networks.
[0011] The present inventive subject matter contemplates a new and improved system and/or method which overcomes the above-referenced problems and others.
SUMMARY
[0012] In accordance with one aspect of the present invention, a method is provided for supporting processing of a transaction conducted between a first party and a second party. The first party accepts payment via a plurality of different payment options selectable by the second party, and the plurality of different payment options are associated with a plurality of different authentication protocols prescribed therefor. The method includes: receiving payment information over a communications network at a server operatively connected to the communications network, the payment information identifying a particular payment option used by the second party for the transaction, and the server being equipped to format and route messages over the communications network in different manners to accommodate the plurality of different authentication protocols; determining from the payment information received at the server which of the different authentication protocols is prescribed for the type of payment option identified in the payment information; selecting, in accordance with the determination, a particular authentication protocol from the plurality of different authentication protocols supported by the server; and, obtaining an authentication determination for the transaction in accordance with the selected authentication protocol, including formatting messages and routing the formatted messages over the communications network in accordance with one or more mandates of the selected authentication protocol.
[0013] In accordance with another aspect of the present invention, a system is provided for supporting processing of a transaction conducted between a first party and a second party. The first party accepts payment via a plurality of different payment options selectable by the second party, and the plurality of different payment options are associated with a plurality of different authentication protocols prescribed therefor. The system includes: means for receiving payment information over a communications network at a server operatively connected to the communications network, the payment information identifying a particular payment option used by the second party for the transaction, and the server being equipped to format and route messages over the communications network in different manners to accommodate the plurality of different authentication protocols; means for determining from the payment information received at the server which of the different authentication protocols is prescribed for the type of payment option identified in the payment information; means for selecting, in accordance with the determination made by the means for determining, a particular authentication protocol from the plurality of different authentication protocols supported by the server; and, means for obtaining an authentication determination for the transaction in accordance with the selected authentication protocol, including means for formatting messages and routing the formatted messages over the communications network in accordance with one or more mandates of the selected authentication protocol.
[0014] Numerous advantages and benefits of the present inventive subject matter will become apparent to those of ordinary skill in the art upon reading and understanding the present specification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The present inventive subject matter may take form in various components and arrangements of components, and/or in various steps and arrangements of steps. The drawings are only for purposes of illustrating preferred embodiments and are not to be construed as limiting.
[0016] FIG. 1 is a block diagram illustrating a typical e-commerce transaction carried out in accordance with an exemplary authentication initiative/program of a credit card network.
[0017] FIG. 2 is a diagrammatic illustration showing a high level overview of an exemplary processing of an authenticated commercial transaction in accordance with aspects of the present inventive subject matter.
[0018] FIG. 3 is a block diagram illustrating an exemplary merchant server and exemplary merchant authentication processing system in accordance with aspects of the present inventive subject matter.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0019] For clarity and simplicity, the present specification shall refer to structural and/or functional network elements, entities and/or facilities, relevant standards, protocols and/or services, and other components that are commonly known in the art without further detailed explanation as to their configuration or operation except to the extent the same has been modified or altered in accordance with and/or to accommodate aspects of the present inventive subject matter.
[0020] In accordance with a preferred embodiment, the present inventive subject matter serves as a centralized merchant processing system for authenticated payments, allowing a merchant or their proxy to securely and easily accommodate authentication of consumers and/or cardholders in accordance with a variety of authentication initiatives implemented by credit card networks or other payment networks, and to process electronic transactions through any payment network using a single platform. It also enables merchants or their proxies to process these payments, regardless of which payment network they are to be routed through, with a single implementation. In one version, this is accomplished using “thin-client” communication software which links information with a centralized merchant authentication processing system (MAPS) upon demand. Moreover, it allows them or a funding source to use the established underlying payment processing infrastructure to process their credit/debit or other payment instruments at participating merchant sites.
[0021] The advantages to funding sources are: the ability to authenticate users and process all electronic transactions through a single platform; the ability to seamlessly process payments using any given payment network; a reduction in processing costs; increased use of their credit/debit or other payment instrument; increased acceptance of their credit/debit or other payment instrument; the ability to send authenticated payment and authorization requests to any network; the ability to receive detailed consumer purchasing behavior statistics. Likewise, there are advantages to the merchant, including, but not limited to: the ability to comply with, participate in, and enjoy the benefits of a variety of different authentication initiatives; the ability to authenticate consumers using different payment vehicles or credit cards, thereby avoiding lost sales; and, protection from fraud.
[0022] The approach detailed in the present specification provides a secure, scalable and modular solution for merchants to participate in and support various payment authentication initiatives, such as, e.g., Visa's 3-D Secure Verified by Visa (VbV) and MasterCard's SecureCode and/or Secure Payment Application (SPA). It provides payment gateways, acquirers, merchant service providers (MSP) and independent sales organizations (ISO) an easy and effective way to provide their merchants with the means for cardholder or account holder authentication, as defined by various authenticating programs, e.g., VbV, SecureCode, SPA, etc.
[0023] With reference to FIG. 2 , a high level overview of an exemplary commercial transaction carried out in accordance with aspect of the present inventive subject matter is diagrammatically illustrated. Via a computer, a consumer 50 shops at an on-line merchant 60 using a selected payment instrument. When the transaction is completed, transaction details are sent from the merchant 60 to a transaction processing service provider (TPSP) 70 that formats and routes various messages and takes other defined actions on behalf of the merchant 60 in accordance with authentication protocols prescribed by the payment processing network to which the payment instrument being used for the transaction belongs. For example, as shown, there is an ATM card payment processing network 70 , a first credit card payment processing network 72 for a first type or brand of credit card, a second credit card payment processing network 74 for a second type or brand of credit card, a check card payment processing network 76 , and a private label credit card processing network 78 , all of which optionally support different authentication protocols. Of course, optionally, other types of payment processing networks may also be included. As shown, the TPSP 70 optionally obtains transactions from the merchant and distributes them to the proper payment processing networks, e.g., for direct authentication by the entity issuing the payment instrument used in the transaction. Having obtain an authentication determination, the authentication service provider 70 then returns this determination to the merchant 60 so that it may be included when the transaction is submitted by the merchant 60 to the established underlying payment processing infrastructure, e.g., via an optional payment gateway 80 .
[0024] More specifically, with reference to FIG. 3 , an exemplary server 100 operated by an on-line merchant and an exemplary merchant authentication processing system (MAPS) 200 are shown. The merchant server 100 includes a checkout processing function 102 , a payment processing function 104 and a thin-client 106 operative to provide interworking between the server 100 and the MAPS 200 . The server 100 suitably hosts a website accessible over a communications network (e.g., the Internet) by consumers/cardholders to conduct commercial transactions, i.e., to purchase good and/or services. That is to say, a consumer/cardholder using an appropriate web browser or like application may connect to the server 100 over the Internet to shop on the hosted website.
[0025] Suitably, when a consumer/cardholder is done shopping, the checkout processing function 102 is invoked thereby providing the consumer's web browser with a checkout webpage whereby the transaction amount (i.e., the total amount of payment due) is established and/or presented and payment information collected. The checkout processing function 102 supports payment with a plurality of different types of payment instruments, e.g., credit and/or debit cards, belonging to different payment processing networks, e.g., Visa®, MasterCard®, etc. Alternately, other payment options may include PayPal®, Bill Me Later®, Western Union, Secure eBill, etc. That is to say, the consumer/cardholder optionally selects the particular type of payment instrument or payment method being used for the commercial transaction from a plurality of supported payment types. Additionally, the checkout processing function 102 is also used to collect the card number, expiration date, and other relevant payment data from the consumer/cardholder.
[0026] The payment processing function 104 submits completed transactions to the established underlying payment processing infrastructure (i.e., payment gateway, acquiring bank, payment processing network, issuing bank, etc.) in the usual manner as prescribed by the various payment processing networks.
[0027] The merchant's thin-client 106 is used for communicating transaction data elements such as card number, account number or name, transaction amount, etc. between the merchant's website and the MAPS 200 . The thin-client is not aware of the specific processing logic or protocols prescribed for each payment authentication initiative. Suitably, the thin-client 106 is a small software component installed on the merchant's server 100 , e.g., approximately 50 kilobytes in size. Alternately, the following options for connecting to the MAPS 200 are also available in order to cater to different merchants depending upon the merchant's transaction processing volume, technical expertise, resource availability and software standards: (i) an “easy connection” implementation, as it is termed herein, i.e., a software-less merchant client; and (ii) a “direct connection” implementation, as it is termed herein, i.e., a direct integration within the MAPS 200 . Nevertheless, the thin-client approach provides the merchant with a thin (i.e., small) software object (e.g., approximately 50 kilobytes) that is used by the merchant to communicate with the MAPS 200 . Using the thin-client 106 , the merchant can participate within the various payment authentication initiatives, e.g., VbV, SPA, etc., without any significant reprogramming of the server 100 or their website. Suitably, the thin-client 106 is available as a COM object or a Java component that is integrated with the merchant's established transaction handling process.
[0028] The thin-client software is used by the merchants to securely communicate with the MAPS. The thin-client software is used to format name/value pairs to the designated MAPS message format and securely communicate the message to the MAPS system. Suitably, the thin-client does not hold any payment authentication specific business process logic. The thin-client supports the following features: secure communication to the MAPS 200 , formatting data to the MAPS specific message format, and allowing merchants to access response data.
[0029] Suitably, the architecture of the thin-client 106 includes a request layer 110 and a response layer 112 that sit on top of a message formatting layer 114 that sits on top of a communication layer 116 . The request layer 110 provides an interface that can be accessed by the merchant's web site to provide data to the thin-client 106 in the form of name/value pairs. The request layer 110 also exposes functions for the merchant to send messages to a specific MAPS 200 . The response layer 112 provides an interface for returning responses to the website, e.g., returned as a function call response to a send message instruction. The message formatting layer 114 formats and translates traffic between the request and response layers 110 and 112 which employ a name/value pairs format and the communication layer 116 which suitably employs an XML format to communicate with the MAPS 200 . Of course optionally, other formats may also be used to communicate with the MAPS 200 , e.g., Simple Object Access Protocol (SOAP), Short Message Service (SMS), a Comma Separated Value (CSV) or other like format (using flat files or batch files), etc. The communication layer 116 provides connectivity with the MAPS 200 , e.g., via HTTPS (i.e., hypertext transfer protocol over secure socket layer (SSL)).
[0030] The MAPS 200 is a core component within the system. The MAPS 200 provides the functionality to merchants for participation in the various different authentication programs and initiatives supported by the payment processing networks. Suitable, the MAPS 200 architecture is extensible to support existing and new releases of existing payment initiatives without requiring a total software rewrite, and likewise accommodates addition of new authentication initiatives. This approach leads to an easy implementation at the merchant website level, i.e., where the processing logic and message handling prescribed by the initiatives are controlled at a central location rather than at an individual merchant level. That is to say, any changes or additions implemented do not affect individual merchants.
[0031] The MAPS 200 provides a secure infrastructure for processing transactions based on payment authentication initiative specifications. The MAPS 200 provides extensible software than can seamlessly support future revisions of the existing payment authentication initiatives and new payment authentication initiatives. Preferably, the MAPS 200 provides complete abstraction as to how each payment authentication initiative is implemented, thereby providing one central location for any changes. Suitably, the MAPS 200 is programmed with Java software to provide the described functionality. The MAPS software architecture includes the following layers: a connectivity layer 210 that sit on top of a message distribution layer 220 that sit on top of a plug-in layer 230 , and external connection layer 240 . The external connection layer 240 provides a generic interface that is used by the MAPS 200 to communicate with outside resources, e.g., the directory or the like as prescribed by various authentication protocols.
[0032] The connectivity layer 210 provides a generic layer for external entities such as merchants to connect to and process a specific payment authentication transaction. The connectivity layer 210 supports the following connectors: an HTTPS server 212 ; a “direct connector” 214 , as it is termed herein; and, an “easy connector” 216 , as it is termed herein; and an optional “other connector” 218 , as it is termed herein.
[0033] The HTTPS server 212 receives and/or sends HTTP messages and communicates them to and/or from the message distribution layer 220 . This connecter is used by the thin-client 106 to communicate with the MAPS 200 . The direct connector 214 provides a Java interface than can be used by a merchant integrating with the MAPS 200 using the direct connection approach. This connector exposes the appropriate Java interfaces than can be used by the merchant during integration. Messages received/sent using this connector are also communicated to/from the message distribution layer 220 . The easy connector 216 provides a web server that is used to communicate with the message distributor and also to communicate with the cardholder. This connector interfaces with the cardholder to perform the merchant functionality and interfaces with the message distributor to communicate the relevant messages. Suitably, the other connector 218 allows the connectivity layer 210 to be expanded to support other communication and custom integration options.
[0034] Implementing multiple connector types provides multiple ways for merchants to integrate and participate within the various authentication initiatives. By providing multiple integration approaches, a wide variety of merchants can be supported depending upon the merchant's technical expertise, resource availability and transaction processing volume. That is to say, in addition to the thin-client approach, a “direct connection” and “easy connection” approach are also optionally available to merchants.
[0035] The direct connection approach is provided for merchants which insist on or otherwise want to host and manage the product, e.g., such merchants may be high transaction volume merchants and/or merchants who have the technical resources to host and manage the product. The merchant can use direct Java calls or the like to interface with the MAPS 200 and communicate the appropriate XML or other like messages. The direct connect interface is also available via a local socket server provided as part of the MAPS 200 . Merchants utilizing a software platform other than Java can use the local socket server. Under the direct connection approach the merchants provide their own hardware and/or software. On the opposite end of the spectrum, the easy connection approach is provided as a software-less integration approach for merchants that do not wish to install the thin-client 106 . Using the easy connect approach, the merchant redirects the cardholder to the MAPS easy connect web server. The web server acts on behalf of the merchant's website and communicates with the MAPS 200 to provide the appropriate processing for the appropriate authentication initiative. Under this approach, the merchant redirects the cardholder using HTTPS posts and receives the responses at a specified response URL. HTTP redirections are performed via the cardholder's browser. Using the easy connection approach the merchant may place an appropriate script after the cardholder/consumer has provided the merchant with appropriate payment data, such as credit card number, expiration date, etc. The merchant receives the authentication response at the URL specified within a response URL field designated in the script.
[0036] The message distribution layer 220 is a component within the software architecture that facilitates scalability, redundancy, high availability and transaction processing speed. Suitably, the message distribution layer 220 is developed using Java 2 Enterprise Edition (J2EE) specifications related to transaction processing. It is preferably a low footprint message distribution application configured to route XML or other like messages to specific plug-in components in the plug-in layer 230 for appropriate transaction processing.
[0037] The plug-in layer 230 includes a plurality of individual authentication initiative plug-in components 232 that listen to the message distribution layer 220 for a specific message type. The respective plug-in component 232 is activated by the message distribution layer 220 that sends messages to the specified plug-in component 232 based upon the type of payment instrument or method being used for the transaction being processed. For example, as shown, the MAPS 200 optionally includes plug-in components 232 for Visa®, MasterCard® and other payment instruments or methods. Notably, the plug-in components 232 are freely and easily updated, exchanged or otherwise manipulated as desired to comply with new version of existing authentication initiatives, or additional plug-in components are freely and easily added to accommodate new initiatives, without any additional alterations to the MAPS 200 or on the merchant side. In this manner, the merchants are automatically kept in compliance with the latest authentication initiatives without having to rework authentication processing protocols on their server 100 . Further, as other payment processing enhancements are introduced and/or desired, e.g., currency conversion, compliant plug-in components therefor may likewise be developed and simply added to the plug-in layer 230 of the MAPS 200 thereby providing the merchant with the particular payment processing functionality.
[0038] Additionally, the plug-in layer 230 optionally also supports various management and/or administrative applications (not shown). For example, a merchant registration application module may be made available to merchant service providers (MSPs) for registering their merchants within the appropriate payment authentication initiatives. Suitably, the merchant registration application offers a web-based application, where the merchants, based on communications received from their MSPs, can register themselves and download appropriate software and related integration documentation. The merchant registration application also provides registration/license key-based control to the MSP, where the MSP can communicate a license key to the merchant that will be used to authenticate the merchant during registration and download. Optionally, the data elements collected from the merchants can be customized as desired by the MSP.
[0039] An optional MSP administration application provides the MSP with a web-based application that is used to administer merchants. The MSP administration application may, e.g., provides the following features: enabling/disabling merchants for use of the MAPS 200 ; maintaining merchant profile information; etc. The MSP administration application is optionally accessed directly via XML/HTTP based application program interfaces (APIs) that may also be used to integrate with other systems. Additionally, a merchant self-service application allows the merchant to access their profile information via the web. For example, the merchant self-service application optionally offers the following features: self profile management; access to transaction history; access to raw message logs related to authentication processes; etc. The merchant self-service application may be similarly accessed directly via XML/HTTP based APIs that are optionally also used to integrate with other systems.
[0040] As another option, a MSP reporting application provides a web-based application for MSPs to view consolidated and individual transaction listings. For example, the following reports may optionally be provided as part of the MSP reporting application: consolidated transaction count/dollar volume reports; individual transaction reports; raw message logs; merchant registration reports; and/or other customized reports.
[0041] As will be appreciated by those of ordinary skill in the art, the MAPS 200 provides a method for authenticating a consumer using one of a plurality of different types of payment instruments (e.g., credit/debit cards) or payment methods to conduct a commercial transaction over a communications network with a merchant employing the MAPS 200 . The payment instrument or method may be either enrolled in or not enrolled in an authentication program conforming to one of a plurality of authentication protocols prescribed for the respective plurality of different types of payment instruments by payment networks supporting the same.
[0042] Suitably, via the thin-client approach (or alternately the direct or easy connection approaches) the MAPS 200 obtains payment information for the transaction from the merchant's server 100 . Suitably, the payment information includes a number or name identifying the particular payment instrument or account being used (i.e., the card number or account number or account name), an expiration date, transaction details (i.e., the transaction amount, etc), and other pertinent payment data. In the case of the thin-client approach, the payment information is obtained from the merchant's website or page via the request layer 110 in the form of name/value pairs. The request layer 110 passes the payment information to the message formatting layer 114 that translates it into an XML or otherwise appropriately formatted message and passes it to the communication layer 116 . The communication layer 116 then passes the message in the XML format or other suitable format to the MAPS 200 via the HTTPS server 212 in the connectivity layer 210 .
[0043] Upon receiving the payment information, the MAPS 200 determines the type of payment instrument or method being used from the payment information. Notably, the payment processing network to which a credit/debit card belongs can be determined from the card number as is known in the art.
[0044] Optionally, the MAPS 200 determines from the enrollment status of the particular payment instrument or account being used for the transaction. For example, the MAPS 200 may maintain a local cache or database of card numbers that identifies those payment instruments enrolled for participation in various authentication programs and/or initiatives. If the particular payment instrument being used is not enrolled in a particular authentication program for the determined type of payment instrument or method, then the process may be ended at this point with the MAPS 200 returning a “not enrolled” message or data back to the thin-client 106 installed on the merchant's server 100 . Accordingly, the thin-client 106 passes this information to the payment processing function 104 to be bundled with the transaction data for submission of the completed transaction to the established underlying payment processing infrastructure. It is to be appreciated, that the returned “not enrolled” message or data, as with all such information returned to the merchant, is provided by the MAPS 200 through the thin-client 106 (i.e., through the communication layer 116 , the message formatting layer 114 and the response layer 112 ) such that it emerges already formatted and/or otherwise in compliance with the appropriate authentication protocols prescribed so that the merchant does not have to manipulate the data further prior to submission to the established underlying payment processing infrastructure.
[0045] Alternately, if the particular payment instrument being used is enrolled in an authentication program, then the payment information is passed to the message distribution layer 220 that routes it to the proper plug-in component 232 in the plug-in layer 230 . The plug-in component 232 then handles, administers and/or otherwise executes set procedures prescribed for the respective authentication program employing the appropriate protocols and/or logic to obtain an authentication determination for the transaction. For example, the plug-in component 232 formats and routes messages in accordance with the authentication protocols prescribed for the determined type of payment instrument or method being used. Having obtained the authentication determination, the MAPS 200 returns the same to the merchant's server 100 .
[0046] Suitably, the plug-in components 232 are programmed to administer any of a variety of authentication protocols as may be prescribed for different types of payment instruments or methods support be various payment processing networks. For example, to accommodate a particular authentication initiative, a particular plug-in component 232 optionally formats and routes a messages to an issuing entity, e.g., an issuing bank having issued the particular payment instrument being used for the transaction, requesting that the issuing entity confirm the enrollment status of the particular payment instrument being used for the transaction. Upon obtaining a response to the enrollment request message from the issuing entity, the information may be returned to the merchant's server 100 in the same manner as if the MAPS 200 performed the enrollment check itself.
[0047] Additionally, once the enrollment status is determined to be positive, the operative plug-in component 232 optionally formats and routes a second message to the merchant such that the consumer/cardholder is redirected to the issuing entity for completing authentication directly therewith, whereupon the authentication determination is made. A response containing the authentication determination made by the issuing entity is then returned in accordance with routing instructions contained in the second message so that it is obtained by the MAPS 200 . Suitably, the routing instructions include a universal resource locator (URL) directing the response back to the MAPS 200 . Optionally, the plug-in component 232 verifies that the response to the second message was obtained from the issuing entity, e.g., by checking a digital signature incorporated with the response. The MAPS 200 is also optionally equipped to detect and/or qualitatively evaluate the level and/or type of authentication employed to arrive at the authentication determination, and this information may be communicated to the merchant or others.
[0048] To further comply with another selected authentication initiative, a particular plug-in component 232 is optionally programmed such that the MAPS 200 is equipped to dynamically add one or more data fields to the merchant's webpage so as to bring the merchant's webpage into conformity with prescribed authentication protocols for the determined type of payment instrument. Additionally, other data elements and/or fields may optionally be dynamically added, e.g., to provide currency conversion, etc.
[0049] Suitably, the MAPS 200 further includes a database (not shown) in which historical records of transactions processed by the MAPS 200 are maintained. The historical records can then be optionally accessed by the merchants or MSPs to perform audit trail and/or reconciliation operations.
[0050] It is to be appreciated that the foregoing description and the accompanying figures are merely exemplary in nature. In particular, other hardware and/or software configurations recognizable to one of ordinary skill in the art may be employed to implement the present invention, and other similar payment authentication initiatives, i.e., other than the exemplary VbV and SPA, may likewise be supported without departing from the scope of the present invention. Nevertheless, the architecture described in the present specification achieves certain benefits. For example, the availability of multiple implementation approaches (i.e., thin-client, direction connection and easy connection) allows a customized fit to a variety of differently equipped merchants based upon their transaction processing volume, technical expertise, software and/or hardware resources, etc. Further, the centralized MAPS 200 removes the burden otherwise placed on the merchant's server 100 having to support multiple payment processing initiatives providing substantially complete abstraction related to individual payment authentication initiative processing rules and logic, and with its extensible plug-in layer 230 , provides availability to multiple payment authentication initiatives with one implementation on the merchant side.
[0051] Additionally, where the merchant employs a MSP to perform payment processing and/or related tasks on the merchant's behalf, it is to be appreciated that the MSP may effectively step into the position of the merchant relative to the MAPS 200 . For example, rather than the thin-client 106 being installed on the individual merchant's server 100 , it may be installed on the MSP's server which may use it on behalf of a single merchant or multiple merchants serviced by the MSP. That is to say, information and/or data to and/or from respective merchants would first be routed through the MSP's server where it is exposed to and/or interacts with the thin-client 106 installed thereon in essentially the same manner as described above. Of course, any other suitable proxy may similarly take the position of the merchant. Moreover, rather than returning authentication determinations and/or other transaction processing results back to the merchant, it is to be appreciated that optionally the information or results may be sent or directly forwarded from the MAPS 200 to any other selected or designated entity within the chain completing back-end processing of the completed transaction, e.g., a merchant's payment gateway, acquiring bank, payment or credit card network, issuing bank, etc.
[0052] The invention has been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon a reading and understanding of this specification. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. | A method is provided for supporting processing of a transaction conducted between two parties. The method includes: receiving payment information over a communications network at a server operatively connected to the network, the payment information identifying a particular payment option used by the second party for the transaction, and the server being equipped to format and route messages over the network in different manners to accommodate the different authentication protocols; determining from the payment information received which of the different authentication protocols is prescribed for the type of payment option identified in the payment information; selecting a particular authentication protocol from the plurality of different authentication protocols supported by the server; and, obtaining an authentication determination for the transaction in accordance with the selected authentication protocol, including formatting messages and routing the formatted messages over the network in accordance with the mandates of the selected authentication protocol. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. provisional application No. 60/866,408, filed 17 Nov. 2006, which is hereby incorporated by reference as though fully set forth herein.
BACKGROUND
[0002] a. Field of the Invention
[0003] The instant invention relates to a voltage management system for one or more energy storage cells.
[0004] b. Background
[0005] Energy storage devices are used to power many electrical devices. The energy storage devices may include one or more energy storage cells connected in series and/or parallel to provide an output voltage. The energy storage device can be charged to store energy in the energy storage device and can be discharged to provide that energy to a load.
[0006] When the energy storage device is being charged one or more energy storage cells of the energy storage device may become overcharged. In order to prevent a potentially dangerous or harmful condition, the charging current is and energy stored in the one or more overcharged energy storage cells is dissipated from the cells until the voltage of the cell reaches a predetermined maximum voltage level.
[0007] Similarly, when the energy storage device is being discharged, one or more of the energy storage cells of the energy storage device may reach a minimum desired charge level. In double layer capacitors and certain types of rechargeable batteries, for example, a predetermined minimum charge level may be desired to be maintained in each energy storage cell of the energy storage device. When this minimum charge level is reached, the discharge of the energy storage device may be stopped and/or a charging current may be applied to the energy storage device to recharge the one or more energy storage cells.
BRIEF SUMMARY
[0008] In one embodiment, an active voltage management device for actively managing a voltage level of an energy storage device is provided. The active voltage management device comprises: a pair of input terminals adapted to be connected to the energy storage device; a reverse polarity protection circuit coupled to the pair of input terminals; a voltage comparator circuit adapted to compare a second voltage associated with the voltage level of the energy storage device to a reference voltage and to provide an output based upon the comparison of the second voltage to the reference voltage; and a transistor adapted to operate in a linear mode to dissipate energy from the energy storage device at a substantially constant current level, wherein output of the voltage comparator circuit is adapted to activate the transistor when the second voltage is greater than or equal to the reference voltage.
[0009] In another embodiment, a method of actively managing a voltage level of an energy storage device is also provided. The method comprises: receiving an input voltage from the energy storage device; providing reverse polarity protection from the energy storage device; comparing the a second voltage associated with the input voltage from the energy storage device to a reference voltage; and conducting a transistor in a linear mode to dissipate energy from the energy storage device at a substantially constant current level when the second voltage is greater than or equal to the reference voltage.
[0010] The foregoing and other aspects, features, details, utilities, and advantages of the present invention will be apparent from reading the following description and claims, and from reviewing the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Embodiments of the disclosed method and apparatus will be more readily understood by reference to the following figures, in which like reference numbers and designations indicate like elements.
[0012] FIG. 1A illustrates a block diagram of one embodiment of a system for balancing an electrical output of two individual energy storage cell elements.
[0013] FIG. 1B illustrates a block diagram of another embodiment of a system for balancing an electrical output of two individual energy storage cell elements.
[0014] FIG. 2 illustrates a block diagram of one embodiment of a system for balancing an electrical output of four individual energy storage cell elements.
[0015] FIG. 3A , labeled as sub-parts 3 A- 1 and 3 A- 2 , illustrates a block diagram of a top-level view of a single cell balancing system.
[0016] FIG. 3B illustrates a block diagram of a low-level view of a single cell balancing system.
[0017] FIG. 4A illustrates a block diagram of a top-level view of a multiple cell balancing system.
[0018] FIG. 4B , labeled as sub-parts 4 B- 1 and 4 B- 2 , illustrates a block diagram of a low-level view of a multiple cell balancing system.
DETAILED DESCRIPTION
[0019] A system and method for actively managing one or more individual energy storage elements is provided. In one embodiment, for example, a voltage management system may actively manage a voltage level of an energy storage element by dissipating energy from the energy storage element when a voltage level of energy storage element is greater than and/or equal to a predetermined voltage level. The energy storage element may include one or more individual energy storage cells. The individual energy storage cells may include any type of rechargeable energy storage cell, such as a capacitor, a double layer capacitor, a rechargeable battery cell, and/or a hybrid cell.
[0020] FIG. 1A shows an embodiment of a system 100 A for managing an energy storage unit 102 , an active voltage management module element 105 , and a plurality of energy monitoring elements 106 . The energy storage unit 102 comprises a plurality of individual storage cells 111 and 119 . In one embodiment, the plurality of individual energy storage cells 111 and 119 comprise capacitors, although the energy storage cells 111 and 119 may comprise secondary batteries (e.g., lithium ion batteries, nickel cadmium batteries, lead-acid batteries), hybrid cells, or other types of energy storage devices. In this embodiment, the energy storage unit 102 provides an electrical payload output to a first terminal 101 and a second terminal 121 . The energy storage unit 102 comprises a maximum operating voltage, a nominal operating voltage, an actual operating voltage, and individual energy storage cell outputs for each of the plurality of energy storage cell elements 111 and 119 of the energy storage unit 102 .
[0021] The energy storage unit 102 is operatively coupled to the at least one active voltage management module element 105 and, therefore, the plurality of individual storage cells 111 and 119 are operatively coupled to the active voltage management module element 105 . As will be described in greater detail below, the active voltage management module element 105 is adapted to dissipate energy from at least one of the individual storage cells 111 and 119 when a voltage level of the storage cell is greater than and/or equal to a predetermined threshold.
[0022] The plurality of energy monitoring elements 106 is operatively coupled to the active voltage management module element 105 . As will be described in greater detail below, the plurality of energy monitoring elements 106 are adapted to monitor various aspects related to the electrical output or operating conditions of the plurality of energy storage elements 111 and 119 , and/or detect a change in the electrical output or operating conditions being monitored. In one embodiment, the plurality of energy monitoring elements 106 comprises four monitoring units 103 , 113 , 115 , and 117 . The plurality of energy monitoring elements 106 measures various electrical and/or physical parameters of the system 100 A. In one embodiment a life data summing stage 107 is operatively coupled to the plurality of energy monitoring elements 106 . The life data summing stage 107 may, for example, generate control signals and/or perform calculations based upon inputs received from the monitoring elements 106 .
[0023] FIG. 1B shows one embodiment of a system 100 B for managing an energy storage unit 102 comprising a plurality of individual energy storage cells 111 and 119 . In this embodiment, a plurality of energy monitoring elements 106 comprises a linearized temperature monitor element 103 , a voltage discharge monitoring element 113 , a nominal voltage monitoring element 115 , and a maximum voltage monitoring element 117 . The linearized temperature monitor element 103 measures a temperature of the voltage management module element 105 , an individual energy storage cell, and/or the energy storage unit 102 . The nominal voltage monitoring element 115 measures a nominal voltage output of energy storage unit 102 . In one embodiment, the nominal voltage output of each cell in the energy storage unit 102 is about 2.7 volts. Although specific monitoring elements are discussed, other types of monitoring elements may be used either instead of or in addition to the ones discussed above. As shown in FIG. 1B , the system 100 B may be isolated (e.g., optically isolated) from a control system to protect the control system.
[0024] FIG. 2 shows one embodiment of a system 200 for managing an energy storage unit 202 . The energy storage unit 202 comprises a plurality of individual energy storage cells 211 , 219 , 223 , and 225 . In this embodiment, a voltage management module element 205 is adapted to dissipate energy from at least one of the individual storage cells 211 , 219 , 223 , and 225 when a voltage level of the storage element is greater than or equal to a predetermined threshold. The system 200 further comprises a plurality of energy monitoring elements 206 , which measure and/or monitor an output of the voltage management module element 205 , an output of the energy storage unit 202 , and/or one or more operating conditions of the voltage management module element 205 and the energy storage unit 202 . A life data summing stage 207 is operatively coupled to the plurality of energy monitoring elements 206 . The life data summing stage 207 may, for example, generate control signals and/or perform calculations based upon conditions being monitored by one or more of the monitoring elements 206 .
[0025] In one embodiment, the plurality of energy monitoring elements 206 comprises four monitoring units 203 , 213 , 215 , and 217 . The plurality of energy monitoring elements 206 measures various electrical conditions and/or physical parameters of the system 200 , such as voltage, current, and/or temperature. The plurality of energy monitoring elements 206 provide information to the system 200 regarding outputs of the plurality of individual energy storage cells 211 , 219 , 223 , and 225 . The system 200 may generate control signals and/or perform calculations based upon the conditions being monitored by the plurality of energy monitoring elements 206 , such as via the life data summing stage 207 . In one embodiment, the plurality of energy monitoring elements 206 detect a change in output voltage of the individual energy storage cells 211 , 219 , 223 , and 225 . The system 200 is also adapted to dissipate energy from at least one of the individual storage cells 211 , 219 , 223 , and 225 via the voltage management module element 205 when a voltage level of the storage cell is greater than or equal to a predetermined threshold.
[0026] FIG. 3A shows a top-level schematic diagram of an energy storage system 300 . The energy storage system 300 comprises an energy storage unit device 302 , a plurality of voltage management devices 304 , and a stop charge control block 306 that is a component of a life data summing element. The energy storage unit device 302 comprises a plurality of individual energy storage cells connected in series. Each of the individual energy storage cells is coupled to an individual voltage management device 304 . Each of the individual voltage management devices 304 is adapted to dissipate energy from the individual energy storage cell coupled to it when the voltage level of the cell is greater than or equal to a predetermined voltage. The voltage management devices 304 , for example, reduce the voltage of the individual cells when those cells have a voltage level greater than desired.
[0027] The voltage management devices 304 may also generate a signal (e.g., a STOP_CHARGE signal) to be provided to a control system indicating that an overcharge condition has been reached in an energy storage cell. The signal is provided to the stop charge control block 306 . When the signal is asserted by the voltage management device 304 , a transistor Q 8 of the stop charge control block 306 is turned on to conduct current through an LED U 2 of an optical isolator. The output of the optical isolator, in turn, provides an isolated control signal to a system controller, such as via an open collector output configuration of the isolator. In the embodiment of FIG. 3B , the stop charge control block 306 provides a control signal if any one of the voltage management devices 304 detects an overcharge condition on an energy storage cell. In other embodiments, the stop charge control block 306 may provide a stop charge control signal to a system controller if each of the voltage management devices 304 or a subset of the voltage management devices 304 detects an overcharge condition on their associated energy storage cells.
[0028] FIG. 3B shows a schematic diagram of a single cell voltage management circuit 304 . The single cell voltage management circuit 304 is coupled to a single energy storage cell (e.g., a capacitor, secondary battery, or hybrid cell) of the energy storage unit device 302 as shown in FIG. 3A . The energy storage cell is coupled to the voltage management circuit 304 via a first electrical contact point 303 and a second electrical contact point 305 . The voltage management circuit 304 monitors an output voltage of the energy storage cell. In one embodiment, the voltage management circuit compares the output voltage to a reference voltage value. If the output voltage is greater than the reference voltage value, the voltage management circuit dissipates energy from the energy storage cell to reduce the voltage of the cell to a level less than or equal to the reference value.
[0029] As shown in FIG. 3B , a reverse polarity protection circuit 310 is connected to the first electrical contact point 303 and the second electrical contact point 305 . The reverse polarity protection circuit 310 protects the voltage management circuit 304 if the energy storage cell is connected in the wrong orientation or if the voltage of the cell goes negative during discharge. In the particular embodiment shown in FIG. 3B , the reverse polarity protection circuit comprises a p-channel MOSFET Q 1 A. A drain of the MOSFET Q 1 A is connected to the first electrical contact point 303 , and a gate of the MOSFET Q 1 A is connected to the second electrical contact point 305 . If the voltage level at the gate (i.e., at the second electrical contact point 305 ) is greater than the voltage level at the drain (i.e., at the first electrical contact point 301 ), the MOSFET Q 1 A prevents current from flowing from the energy storage device. If the voltage level at the drain is greater than the voltage level at the gate, the MOSFET Q 1 A allows current to flow from the energy storage device to the voltage management circuit 304 . The low on-resistance of the MOSFET Q 1 A provides a very low loss reverse polarity protection circuit 310 . Although one embodiment of a reverse polarity protection circuit is shown in FIG. 3B , one skilled in the art would recognize from this disclosure that other embodiments could also be used.
[0030] In the embodiment shown in FIG. 3B , the voltage management circuit 304 also comprises a resistor voltage divider including resistors R 18 A and R 21 A, a filter capacitor CIA, and a voltage comparator U 1 A. The resistor voltage divider including resistors R 18 A and R 21 A provides a fraction of the voltage level provided to the circuit 304 as an input voltage to the voltage comparator U 1 A. The filter capacitor C 1 A forms a low pass filter with resistor R 18 A that prevents oscillations and suppresses transients.
[0031] The voltage comparator U 1 A comprises an integrated reference voltage comparator. The comparator U 1 A is configured in an open drain output configuration that pulls an inverted output OUT low until a voltage threshold is reached at the input to the comparator. When the input voltage reaches the voltage threshold, however, the comparator U 1 A sinks current at the inverted output OUT. The voltage comparator receives an input voltage from the resistor voltage divider and compares that input voltage to the threshold voltage level of the comparator. The inverted output OUT provides an output based on the comparison of the input voltage to the threshold voltage of the comparator. In the embodiment shown in FIG. 3B , for example, the threshold voltage comprises about a 2.2 volt trigger corresponding to an energy cell voltage of about 2.8 volts. The inverted output OUT of the voltage comparator U 1 A is low when the input voltage provided by the voltage divider is less than the threshold voltage of the comparator. The inverted output OUT of the voltage comparator sinks current from the transistor Q 5 A to turn the transistor Q 5 A on when the input voltage is greater than or equal to the threshold voltage of the comparator. The transistor Q 5 A in turn turns on the transistor Q 2 A which also in turn turns on the transistor Q 4 A.
[0032] In the embodiment shown in FIG. 3B , the voltage comparator U 1 A also provides a hysteresis window that prevents the voltage management circuit 304 from oscillating. In one embodiment in which a resistor R 19 A is not included in the circuit, the hysteresis of the voltage comparator U 1 A can be preset at a predetermined level (e.g., 110 mV). By adding the resistor R 19 A, the hysteresis window can be increased by a voltage level depending on the value of the resistor 19 A added to the circuit 304 .
[0033] In one embodiment, the transistor Q 4 A operates in a constant current linear mode to dissipate energy from the energy storage cell coupled to the voltage management circuit 304 at a constant rate of discharge. By using the transistor in a constant current linear mode to dissipate energy instead of primarily relying on a resistor to dissipate the majority of the energy from the energy storage cell, the discharge of current can be held constant regardless of the voltage level of the energy storage cell and further allows the resistors of the circuit 304 to be sized smaller than if the resistors were used as the primary discharge mechanism. A transistor Q 7 A can also be used to provide an overcurrent protection for the transistor Q 4 A.
[0034] In one embodiment, for example, the transistor Q 4 A may draw approximately 300 mA. In this embodiment, the transistor Q 4 A may dissipate at least the majority of the energy dissipated from the energy storage cell. The resistors R 9 A and R 10 A also dissipate energy from the energy storage cell, but in one embodiment dissipate less than half of the total energy dissipated from the energy storage cell.
[0035] The voltage management circuit 304 shown in FIG. 3B also provides an indicator, such as a light emitting diode (LED) D 2 A, to indicate when the voltage management circuit is actively dissipating energy from the energy storage cell (or when the voltage management circuit is not actively dissipating energy from the energy storage cell). In the embodiment shown in FIG. 3B , for example, the LED is activated by transistor Q 2 A described above.
[0036] The voltage management circuit 304 also comprises a control signal STOPCHARGE via transistors Q 6 A and Q 3 A to indicate when the circuit 304 is actively dissipating energy from an energy storage cell. The control signal, for example, may be used to control a charging current being applied to the energy storage cell connected to the voltage management circuit 304 .
[0037] In one embodiment, the voltage management circuit 304 draws a low quiescent current when the circuit is not actively dissipating energy from an energy storage cell. The voltage management circuit 304 , for example, may draw a quiescent current of approximately 50 μA. Where the dissipation current is approximately 300 mA, for example, a ratio of the dissipation current to the quiescent current is approximately 6000. In other embodiments, for example, the ratio of the dissipation current to the quiescent current is greater than approximately 1000, greater than approximately 2000, greater than approximately 4000, greater than approximately 5000, or greater than approximately 6000.
[0038] FIG. 4A shows a top-level schematic diagram of a multi-cell voltage management system 400 . The multi-cell voltage management system 400 comprises a plurality of multi-cell voltage management circuits 408 that are each coupled to a plurality of energy storage cells of an energy storage unit 402 . In one embodiment, for example, the energy storage unit is a module that comprises eighteen energy storage cells connected in series. In this embodiment, the multi-cell voltage management system 400 comprises three voltage management circuits 408 each coupled to six of the series-connected energy storage cells.
[0039] Each of the multi-cell voltage management circuits 408 each monitor the voltage of the plurality of energy storage cells coupled to the circuit 408 . If the monitored voltage of the plurality of energy storage cells is greater than or equal to a predetermined threshold voltage, the multi-cell voltage management circuit dissipates energy from the plurality of energy storage cells. In the embodiment shown in FIG. 4A , the individual multi-cell voltage management circuits 408 may also provide control signals. These control signals may, for example, be used to stop a charging current from being applied to the plurality of energy storage cells, initiate a charging current to be applied to the plurality of energy storage cells, provide a warning or indicator or an over-voltage condition, or provide another type of warning or ameliorative action.
[0040] Low voltage control block 404 and stop charge block 406 operate similarly to stop charge control block 306 described above with reference to FIG. 3A to provide isolated control signals to a system controller for a low voltage control signal and a stop charge control signal, respectively. The low voltage control signal, for example, may be used to disconnect one or more energy storage cell from a load and/or to initiate a charge operation to recharge one or more energy storage cell. Low voltage control block 404 and stop charge control block 406 each comprise a resistor-capacitor (RC) filter on the input of the transistor Q 6 . The RC filter reduces noise on the control line entering the control block.
[0041] FIG. 4B shows an individual voltage management circuit 408 of the voltage management system 400 shown in FIG. 4A . The individual voltage management circuit 408 comprises a reverse polarity protection circuit 403 , a voltage regulator circuit 405 , a first comparator circuit 406 , a second comparator circuit 407 , and an energy dissipation circuit 409 . The voltage management circuit 401 further comprises a first electrical contact point 411 and a second electrical contact point 413 . A plurality of energy storage cells (e.g., a series and/or parallel string of energy storage cells) may be connected between the first electrical contact point 411 and the second electrical contact point 413 . The voltage management circuit 408 may be external to a module including the energy storage cells or may be integrated within the module.
[0042] The reverse polarity protection circuit 403 is the same as the reverse polarity protection circuit 310 described above with respect to FIG. 3B .
[0043] The voltage regulator and reference circuit 405 comprises a voltage regulator and a voltage reference. The voltage regulator comprises a zener diode D 2 , a voltage regulator U 1 , a filter capacitor C 2 , and a voltage clamp diode D 1 . The zener diode D 2 protects the voltage regulator U 1 from an input voltage that is too high for the voltage regulator U 1 . In one embodiment, for example, the zener diode has a breakdown voltage of about 18 volts. The voltage regulator steps down the input voltage from the bank of energy storage cells and provides a fixed output voltage (e.g., about five volts). The zener diode D 3 sets the reference voltage (e.g., about 2.5 volts).
[0044] The voltage reference comprises a resistor R 3 and a reference zener diode D 3 . The voltage reference provides a reference voltage VREF from the output voltage of the voltage regulator U 1 and provides the reference voltage VREF to the first and second comparator circuits 407 and 408 .
[0045] The first comparator circuit 406 comprises a voltage divider and an op-amp. In the embodiment shown in FIG. 4B , for example, the voltage divider comprises a resistor voltage divider including resistors R 1 and R 7 . The op-amp U 2 A compares a voltage provided by the voltage divider and the reference voltage VREF. If the voltage provided by the voltage divider is greater than or equal to the reference voltage VREF, the output of the op-amp U 2 A turns on transistors Q 2 and Q 3 . In the particular embodiment shown in FIG. 4B , the op-amp output is driven low to turn on p-type transistors Q 2 and Q 3 although other embodiments are also possible. The transistor Q 3 (e.g., a p-channel bipolar transistor in the embodiment shown in FIG. 4B ) provides a control signal STOPCHARGE that may be used to turn off a charging current from being applied to the bank of energy storage cells coupled to the voltage management circuit 408 . The transistor Q 2 (e.g., a p-channel MOSFET in the embodiment shown in FIG. 4B ) is part of a buffer circuit formed by the transistor Q 2 and the op-amp U 2 B that in turn turns on dissipation transistor Q 4 that provides constant current dissipation of energy from the bank of energy storage cells coupled to the individual voltage management circuit 408 via contact points 411 and 413 .
[0046] The second comparator circuit 407 also comprises a voltage divider and a comparator. The voltage divider in this embodiment is a resistor voltage divider including resistors R 13 and R 15 . The comparator comprises an op-amp U 2 C that compares a voltage provided by the voltage divider to the reference voltage VREF described above. When the voltage provided by the voltage divider is less than or equal to the reference voltage VREF, the comparator turns on transistor Q 5 to provide a low voltage warning signal LOW_WARN. The low voltage warning signal LOW_WARN may be used, for example, to disconnect the energy storage cells from a load and/or to initiate a charging current to re-charge the energy storage cells. In one embodiment, for example, the low voltage warning signal LOW_WARN may be used to indicate that the energy storage cells are at approximately fifty percent of their rated energy storage capacity, although other embodiments may be used depending on the type of energy storage cells being used.
[0047] Although embodiments have been described above with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this invention. All directional references (e.g., upper, lower, upward, downward, left, right, leftward, rightward, top, bottom, above, below, vertical, horizontal, clockwise, and counterclockwise) are only used for identification purposes to aid the reader's understanding of the present invention, and do not create limitations, particularly as to the position, orientation, or use of the invention. Joinder references (e.g., attached, coupled, connected, and the like) are to be construed broadly and may include intermediate members between a connection of elements and relative movement between elements. As such, joinder references do not necessarily infer that two elements are directly connected and in fixed relation to each other. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure may be made without departing from the spirit of the invention as defined in the appended claims. | An active voltage management device and a method for actively managing a voltage level of an energy storage device are provided. The active voltage management device comprises: a pair of input terminals adapted to be connected to the energy storage device; a reverse polarity protection circuit coupled to the pair of input terminals; a voltage comparator circuit adapted to compare a second voltage associated with the voltage level of the energy storage device to a reference voltage and to provide an output based upon the comparison of the second voltage to the reference voltage; and a transistor adapted to operate in a linear mode to dissipate energy from the energy storage device at a substantially constant current level, wherein output of the voltage comparator circuit is adapted to activate the transistor when the second voltage is greater than or equal to the reference voltage. The method comprises: receiving an input voltage from the energy storage device; providing reverse polarity protection from the energy storage device; comparing the a second voltage associated with the input voltage from the energy storage device to a reference voltage; and conducting a transistor in a linear mode to dissipate energy from the energy storage device at a substantially constant current level when the second voltage is greater than or equal to the reference voltage. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to shafts and, more particularly, to stub arbor shafts, which shafts may be attached and detached to and from members such as large rolls supported by the shafts.
One commercially important use for such shafts is in paper mills where a plurality of rolls of paper are loaded onto a cutting machine and supported on suitable shafts while being cut into sheets. Customarily, each roll is mounted on a bearing at each end of the roll. Shafts of the subject type support the rolls on the bearings. Conventionally, one of the bearings can be reciprocated in the axial direction of the roll and the other bearing can be rotated about a vertical axis in order to align the rolls. The cutting machine runs essentially continuously and while empty rolls are being replaced, the machine is fed from other rolls. On a typical machine, there are six rolls disposed in three rows of two each.
At present it is more time-consuming and a more tedious job to repair this shaft, than the shaft of this application. The ends of the shafts, which extend into the roll, have outer annular rubber bushings. Provision is made in the shaft's construction to compress the bushings axially thereby causing them to bow outwardly into tighter fit within the roll. When the rubber bushing wears, it is necessary to take the shafts apart to replace the bushings. The prior art shafts have the further disadvantage that tools are required to fix the shafts, for example, to replace the bushings, and this entails further labor expense since it is deemed maintenance according to most union contracts, and thus should be done by the maintenance staff and not by the machine's normal work force.
In the existing prior art structure, it is necessary to almost completely disassemble the shaft in order to replace the bushing.
For example, in one prior art shaft structure, snap rings are employed which require special plyers for their removal. Then it is necessary to remove cotter pins and nuts on a rod which extends through the shaft, and then unscrew the cone. Only thereafter can the shaft be disassembled to remove the bushing. The use of snap rings is also disadvantageous since there is the possibility of snap rings coming out during use if improperly installed.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to provide a new and improved support shaft arrangement for rotating rolls and the like.
Another principal object of the invention is to provide a support shaft having a replaceable rubber bushing establishing a connection with a rotating member, which bushing may be replaced with a minimum of disassembly of the apparatus.
The above and other objects, features and advantages of the invention will in part be apparent and will in part be described below. Briefly, a presently preferred embodiment of the invention comprises a roll of paper or the like which is supported by a pair of shafts extending into the hollow core of the roll. For purposes of illustration, the roll will be described as a roll of paper employed on a paper cutting machine in a paper mill. The shaft on one side of the roll, referred to as a bearing shaft, is mounted in a bearing which may be shifted with the roll in an axial direction. The shaft on the other side of the roll, referred to as a journal shaft, is supported on a bearing which conventionally can be rotated about a fixed vertical axis. The axially shiftable bearing may be mounted on a wall, and this represents the shifter side of the cutter or sheeter. The other bearing, which can be rotated about a vertical axis, is typically also mounted on a wall, called the friction side. The purpose of the journal shaft is to support the rolls and put a braking effect on the rolls through the journal shafts to prevent the paper sheets from wrinkling. For this purpose, a friction wheel is put on the journal shaft to control the roll rotation and to keep the paper sheet taut between the roll and the cutter.
The two shafts associated with each roll, although not identical with each other, are basically similar. Each shaft has a roll engaging and/or cone end which is inserted into a bore in the roll. A rubber bushing is mounted at the cone end of the shaft and the bushing may be bowed outwardly to engage the walls of the bore in the roll to provide a driving engagement between the shaft and the roll. The shafts each have axial bores with an adjustment rod extending therethrough and attached to one end, to the cone end, and being accessible from the other end of the shaft. Rotation of the adjustment rod may move the cone end axially relative to the remainder of the shaft to expand or contract the rubber bushing.
Several embodiments of different structures for facilitating removal of the annular rubber bushing from the cone end more quickly than prior art devices are illustrated and will be described in detail hereinafter. For example, in some embodiments the rubber bushing can be slipped off the cone end over an adapter section of the shaft without the adapter section being removed from position relative to the adjustment rod. As another possibility described hereinafter, the head section of the cone may be removed without disrupting the remainder of the apparatus and thereafter the rubber bushing, which has been held in place in part by the cone head, may be removed at the cone end of the apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a roll being supported by a pair of shafts and bearings in accordance with the present invention.
FIG. 2 is an exploded view partly in section of the shaft at the left side of FIG. 1, showing the manner of assembly of the bearing shaft.
FIG. 3 is a view primarily in longitudinal section showing the shaft of FIG. 2 when assembled.
FIG. 4 is an exploded view similar to FIG. 2 but of the shaft at the right side of FIG. 1.
FIG. 5 is a view primarily in longitudinal section showing the shaft of FIG. 4 when assembled.
FIG. 6 is a view in longitudinal cross section of a portion of another embodiment of the invention showing a modified shaft end structure for supporting an annular rubber bushing.
FIG. 7 is a view similar to FIG. 6 of another embodiment of the invention.
FIG. 8 is a longitudinal cross sectional view of a modified shaft end structure in accordance with another embodiment of the invention wherein the rubber bushing may be readily removed.
FIG. 9 is an exploded view of the end of the shaft in accordance with another embodiment of the invention which is designed for ready removal of the rubber bushing without disassembling the main portion of the shaft unit.
FIG. 10 is a longitudinal cross sectional view of another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings and, more particularly, to FIG. 1, reference numeral 10 designates a roll of paper or the like which has a hollow core 11. A first shaft, referred to as a bearing shaft generally designated by reference numeral 12, and a second shaft, referred to as a journal shaft, generally designated by reference numeral 14, are adapted to have their ends inserted into the hollow core 11 until keys 16 engage in complementary recesses 18 in the hollow core. The first shaft 12 has a rear end section 18 between rings 20 and 22 which is rotatably supported in a bearing 24. The bearing 24 and the shaft 12 may be reciprocated in the axial direction of roll 10 via a hand wheel 26.
The journal shaft 14 similarly has a rear section 28 mounted in a bearing 30 which is rotatable about a fixed vertical axis as represented by the arrow 32. A slot 31 at the rear of the shaft 14 permits the shaft to be splined to a friction wheel (not shown).
FIGS. 2 and 3 illustrate the construction of shaft 12 in detail. As shown therein, the shaft is hollow and an adjustment rod 34 extends through the shaft. When in place, the right hand end of the rod 34, which has a configuration of a hexagon 36, is adapted to be engaged by a suitable tool to rotate the rod. The other end of the rod comprises an enlarged head 38 and a threaded section 40. There is an adaptor stop 42 on rod 34 intermediate the threaded section 40 and a further threaded section 44 approximately at the mid-point of the rod. The purpose of the stop 42 is to push the adaptor to its seat in the shaft housing and prevent the adaptor from moving out of place. The threaded intermediate section 44 is threaded into a rod lock 46 which has internal threads 48 and is positioned in recess 50 in the shaft. The outer configuration of rod lock 46 and the inner configuration of recess 50 permit rotation of the rod lock.
An annular rubber bushing 52 is placed onto the annular skirt 54 of shaft end piece or cone 56 which is slipped onto the rod from the right hand end. There are internal threads 58 in end piece 56 for engagement with the threads 40 at the other end of rod 34. Thus, the adjustment rod may be attached to cone end piece 56, the adaptor goes over the rod next followed by a ball bearing unit 60 and the rod lock 46, which is screwed to the rod and pinned by a pin, followed by a belt that wraps around the center of the rod lock to keep the pin from falling out. The rubber bushing is slid on from right to left until it covers the cone skirt before the whole assembly is pushed into the shaft.
The adjusting rod with all the parts on it are placed into the housing as follows. An adaptor 62 is slid along the shaft 12 until one end is pushed against a stop 63, by adaptor stop 42 of adjusting rod 34. The adaptor is hollow with a circular interior bore but with a hexagonal outer surface 64. The hexagonal outer surface 64 is located within an enlarged diameter cone housing area 66 whereas the remainder of the adaptor is positioned within a smaller diameter passage 68 between recess 50 and the housing area 66 when the rod is inserted within the shaft housing. There are tapered apertures 70 in the passage 68 and corresponding tapered recesses 72 in the wall of the adaptor 62. Pins 74 extend through the tapered apertures 70 into the recesses 72 to lock the adaptor in position. A belt 76 is placed around the pins to prevent the pins from falling out.
As seen in FIG. 3, when assembled the portion of the left hand end of adaptor 62 which has a hexagonal or non-circular configuration telescopes within the skirt 54 within housing area 66 with provision for axial movement since the skirt does not extend the entire length of the housing area 66. The right hand end of the rubber bushing 52 abuts against the end 78 of the shaft, and the adaptor stop 42 contacts the end of adaptor 62. At the right hand end of the rod 34 a bushing 80 is inserted into a counterbore 82 with the reduced diameter section 84 of the bearing extending into the axial bore 86 in the shaft 12. Section 84 of the bearing has a tapered opening 88 leading to the central passage 90. The tapered section enables the rod 34 to be slipped into the bushing 80 so that the nut 36 can be passed through the bushing without pushing the bushing out of its seat when the unit is being assembled.
In operation, after the cone end of shaft 12 has been inserted into the core 11 or roll 10, the rubber bushing 52 is pushed outwardly into sealing engagement with the core 11 by rotating the adjusting nut 36 be means of a suitable tool. Because the threaded section 40 of rod 34 engage with the threads 58 of the cone head 56, this causes the skirt to move to the right so that the rubber bushing 52 is compressed between the cone end 56 and the end 78 of the shaft. There would be a tendency for the skirt 54 to rotate with rod 34, but this is prevented due to the non-circular configuration of the inner surface of skirt 54 and the complementary configuration of the section 64 of the adaptor 62. As indicated above, in the illustrated embodiment skirt 54 and end section 64 have a hexagonal configuration. This prevent rotation of the skirt when the rod 34 is being rotated to either expand or contract the rubber bushing 52. Adaptor 62 in turn is prevented from rotating by the tapered pins 74 which connect the adaptor to the shaft and by the hexagonal shape of the adaptor in area 68 of the housing (see FIG. 2).
FIGS. 4 and 5 illustrate the details of the journal shaft 14. Since shaft 14 is basically similar in construction to the bearing shaft 12, the same reference numerals are employed in FIGS. 4 and 5 to designate corresponding parts to those described previously in connection with shaft 12. The manner of connecting shaft 14 to the roll 10 via expansion of the rubber bushing 52 is the same as described previously in connection with shaft 12.
FIG. 6 illustrates a modified shaft end structure in accordance with another embodiment of the invention. In this embodiment there is an end piece or cone 80 with a tubular extension or skirt 82 which telescopes within a noncylindrical, for example, a hexagonal passage 84 in an adaptor 86. The adaptor has a smaller diameter tubular extension 88 which telescopes within a housing 90 that is slightly shorter than the housing of the previously described embodiments. As shown, the adaptor has an annular abutment lip 92 which contacts the outer end of housing 90.
The outer configuration of extension 88 and the complementary shape of the surrounding surface of housing 90 are noncylindrical so that the adaptor does not rotate in housing 90. In view of the contact between the end of housing 90 and the surface 92 of the adaptor, pulling forces generated when a rod 34 is tightened to expand the rubber bushing 52 outwardly are not transmitted to the pins which lock the adaptor to the housing. The pins of this embodiment are comparable to pins 74 and are now shown in this embodiment.
When an adjustment rod 34 is rotated to draw the end piece 80 towards the right as seen in FIG. 6, the rubber bushing 52 is deformed outwardly into locking engagement within roll 10.
FIG. 7 illustrates another modified shaft end structure which comprises an end piece 96, and adaptor 98, and a housing 100. End piece 96 has threads 102 to engage the threads of an adjustment rod 34. The end piece also has a tubular extension or skirt 104 whose end telescopes within a slot 106 in adaptor 98. Slot 106 is noncircular as viewed in transverse cross section. A similar slot 108 in adaptor 98 facing the other direction receives a thin extension 110 of housing 100. In this manner, pulling forces are not transmitted to the pins (not shown) fastening the housing 100 to the small diameter tubular extension 112 of the adaptor.
It will be appreciated that various other constructions of similar nature permitting telescoping movement between the end piece and the adaptor with provision for the adaptor and the housing to have abuting interengagement are possible within the scope of the invention.
FIG. 8 illustrates a modified end piece which might be used, for example, with the shafts of the FIG. 1 embodiment. This end piece has the advantage that the rubber bushing may be removed and replaced without taking the entire shaft apart. An end piece 116, has a tubular extension or skirt 118 and at one end a smaller threaded extension 120 which has both internal and external threads. During assembly a rubber bushing 52 is placed onto the tubular extension 118 starting from the left side. Then an abutment member 121 is threaded onto the external threads of extension 120 followed by a lock nut 122. Should it become necessary to replace the rubber bushing 52, the adjustment rod 34 is loosened releasing pressure of rubber bushing so that lock nut 122 and abutment 121 may be screwed off permitting the bushing 52 to be slipped off of the tubular extension 118 and over the end 38 of the rod 34 (FIG. 2).
FIG. 9 illustrates another embodiment of the invention designated to facilitate removal of a rubber bushing without disassembling the entire shaft. An end piece 124 has a tubular extension or skirt 126 to engage the adaptor. A rubber bushing (not shown) is intended to be slipped onto the tubular extension 126. For holding the bushing in place a spring loaded retaining member having an abutment 128 which projects above the surface of tubular extension 126 and a housing 130 is attached to support plates 132 on the end piece, with springs 134 disposed in the housing and positioned upon pins 136. An annular steel cap 135 has an arcuate groove for receiving and protecting the edge of the rubber bushing. The back of cap 135 contacts the abutment 128. An end cap 138 is threaded onto threaded extension 142 of the end piece. An adjustment rod (not shown) is intended to extend through the central opening 144 in the cap 138 and through threaded extension 142 of the end piece.
FIG. 10 illustrates another embodiment of the invention which includes an adaptor 150 disposed in a housing 152. Housing 152 has a noncircular passageway 154 between spaced chambers 156 and 158. The adaptor 150 has a short, small diameter intermediate tubular portion 160 disposed in passageway 154. The adaptor has a larger diameter right end section 162. When turned 90° from the position illustrated in FIG. 10, the end section 162 may be moved axially in the passageway 154 in the housing. When the end section 162 is in the position shown it cannot be moved axially since its side contacts the adjacent walls of chamber 158. The remainder of adaptor 150 comprises a larger diameter central portion 164 received within chamber 156 in the housing 152 and a left end comprised on a small height octagonal or other noncircular cross section end piece 166 which projects into a chamber 168 in the housing.
When the shaft is tightened, an octagonal cone skirt 182 slides onto the end piece 166. This helps to prevent the adaptor from turning when the shaft is in use. This also prevents turning pressure from being put on the pin 74 holding the adaptor in the housing. If there were no locking action to keep the adaptor from turning, the forces could snap the pins.
End piece 166 projects into cone skirt 170. The interior of the cone skirt is octangonal or other noncircular shape. The exterior of cone skirt 170 is circular, so it can be turned in circular chamber 168 during shaft assembly and disassembly. When the shaft is tightened an octagonal end section 182 of the cone skirt slides to the right on end piece 166 into an octagonal chamber 200 in housing 152, which is no wider than the section 182 of cone skirt. When cone skirt section 182 enters housing chamber 200, the end piece 166, the cone skirt, and the housing become locked together. If for example, the cone skirt is about 5 inches long, about 1 inch at the end section 182 is octagonal. The other 4 inches is round. When octagonal section 182 reaches its limit to travel to the right, it meshes with an octagonal chamber 200. AT the same time the interior octagonal shape of cone skirt 170 is in engagement with the complementarily shaped outer surface of end piece 166. This is an added safety feature of the invention that helps to prevent the adaptor from turning in the shaft housing. This locking effect minimizes the forces being placed upon the pins 74 holding the adaptor in the housing from turning. If for example in the case of a journal shaft, one puts friction on the housing of the shaft through a friction wheel to keep the sheet tight (see FIG. 1). Key 16 that is engaged in recess 18 receives pressure as the roll rotates against the braking effect. The rubber bushing also receives the same pressure because its the driving engagement. If recess 18 was to tear out letting key 16 rotate (this happens when the axil bore of the roll is a fiber core) the rubber bushing would try to rotate with the roll causing the cone skirt to also turn. The cone skirt would turn the adaptor which would shear the pins. But the locking action that prevents the internal parts from turning when the cone skirt moves to the right in FIG. 10 prevents this from happening. Thus, if the axil bore tears out and the roll rotates on the shaft the worst that can happen is damage to the rubber bushing and the core itself. In the case of a steel core this safety feature would not be needed.
From the foregoing description, it will be appreciated that the adaptor cannot be assembled the wrong way beacuse only one end is configured to mesh with the cone skirt.
While presently preferred embodiments of the invention have been shown and described with particularity, various changes may readily suggest themselves to those of ordinary skill in the art upon being apprised of the invention. For example, in view of machining problems the housing might be manufactured in two pieces which are subsequently bonded together. The invention can also be utilized with a thrust ball bearing. The disclosed embodiments are to be taken as illustrative only, and it is intended to encompass all changes and modifications that all within the scope and spirit of the appended claims. | A rotating member, such as a roll of paper is supported by a pair of shafts extending into opposite ends of an axial bore in the rotating member. The shafts, which have rubber bushings which expand outwardly into tight fit within the axial bore, are constructed to enable ready removal of the shafts from the roll, for example, to change the roll. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a Continuation Patent Application of U.S. patent application Ser. No. 09/925,002, filed Aug. 8, 2001 issued as U.S. Pat. No. 7,206,093, which claims the benefit of foreign priority under 35 USC §119(a) to Taiwan, R.O.C. Application Ser. No. 90113920, filed Jun. 8, 2001.
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to a scanning device and a scanning method. More particularly, the present invention relates to a scanning device and a scanning method capable of saving some compensation memory.
2. Description of Related Art
Due to rapid development of multi-media systems, there is a demand for images with a higher resolution. To increase image resolution, the number of light-sensitive cells (such as charge coupled device (CCD)) in the sensing device of a scanner must increase correspondingly.
Because of some intrinsic properties of a charge-coupled device (CCD) or manufacturing deviation, sensitivity of each CCD cell may not be identical. Hence, before scanning an object, the scanner must perform a light-intensity calibration to produce a set of shading values so that image compensation can be conducted subsequently. Any non-uniform light-intensity effects in the pixels generated by the CCD can be compensated for using the shading values. Ultimately, color of the pixel and the color on the target object are identical. To use the shading values in image compensation, the shading values need to be stored in compensation RAM units inside the scanning device. As resolution of a scanner increases, the number of pixels in a CCD increases correspondingly. Since a larger compensation memory must be used to store up the shading values required to compensate the light-intensity of a scanned image, production cost of a scanner increases.
SUMMARY OF THE INVENTION
Accordingly, one object of the present invention is to provide a device and a method of saving compensation memory for holding shading values in a scanner. The shading values are divided into odd shading values and even shading values. The odd and the even shading values are averaged to produce an odd-even shading value. Two consecutive sets of image pixels obtained through a charge-coupled device (CCD) use the same odd-even shading values for image compensation. With this arrangement, only half of the conventional compensation memory in a scanner is required.
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 compenstation memory saving scanning device. The device includes an input device, an application-specific integrated circuit, a compensation memory unit, an image memory unit and an input/output interface. The application-specific integrated circuit couples with the input device, the compensation memory unit, the image memory unit and the input/output interface.
Even data values and odd data values are input to the application-specific integrated circuit via the input device. After performing a computation using the even data values, the odd data values and preset values, the application-specific integrated circuit averages out the even compensation values and the odd compensation values to produce averaged odd-even compensation values. The averaged odd-even compensation values are stored inside the compensation memory unit. Scanned pixel data are stored inside the image memory unit before outputting to the input/output interface.
This invention also provides a scanning method capable of saving some compensation memory. First, even compensation values necessary for compensating even-numbered pixels and odd compensation values necessary for compensating odd-numbered pixels are extracted. The even compensation values and the odd compensation values are averaged to produce averaged odd-even compensation values.
Compensation values necessary for compensating an image must be stored inside a compensation memory unit. To save some compensation memory space, odd compensation values and even compensation values are averaged to produce half as much even-odd compensation values so that only half of the memory is required to hold the data.
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
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,
FIG. 1 is a block diagram showing a scanning device capable of saving compensation memory according to one preferred embodiment of this invention;
FIG. 2 is a schematic diagram of an alternative-sensing device for holding compensation data according to one preferred embodiment of this invention;
FIG. 3 is a schematic diagram of a linear-sensing device for holding compensation data according to one preferred embodiment of this invention; and
FIG. 4 is a flow diagram showing the scanning method for saving some compensation memory according to one preferred embodiment of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
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.
FIG. 1 is a block diagram showing a scanning device capable of saving compensation memory according to one preferred embodiment of this invention. As shown in FIG. 1 , the scanning device includes an input device 10 , an application-specific integrated circuit 16 , a compensation memory unit 18 , an image memory unit 20 and an input/output interface 22 . The input device 10 further includes a sensing device 12 and an analog/digital converter 14 .
The sensing device 12 couples with the analog/digital converter 14 . The analog/digital converter 14 couples with the application-specific integrated circuit 16 . The compensation memory unit 18 , the image memory unit 20 and the input/output interface 22 all couple with the application-specific integrated circuit 16 .
FIG. 2 is a schematic diagram of an alternative-sensing device for holding compensation data according to one preferred embodiment of this invention. In this embodiment, the alternative-sensing device of FIG. 2 may be used as the sensing device 12 of FIG. 1 . Before the scanning device scans an image object, a compensation procedure is performed. In general, white is used as a compensation color. When the scanning device is conducting a compensation procedure, CCD cells 1×.about.N× ( FIG. 2 ) of the sensing device 12 of FIG. 1 will convert the sensed light intensity into respective currents and transfer to the storage electrodes for producing signal charges. The charges are then transformed to appropriate voltage differential. The alternative-sensing device uses such procedure to perform an alternate scanning of the compensation white so that a multiple of alternative scanning pixels are output to the analog/digital converter 14 of FIG. 1 . In addition, a linear sensing device similar to the one shown in FIG. 3 may also be used as the sensing device 12 of FIG. 1 .
As the analog/digital converter 14 of FIG. 1 receives the alternately scanned image pixels, alternate scanned pixels in an analog format are digitized into even data values and odd data values. Thereafter, the even data values and the odd data values are transferred to the application-specific integrated circuit 16 of FIG. 1 .
The application-specific integrated circuit 16 of FIG. 1 receives the even data values and the odd data values. After performing a computation using the even data values, the odd data values and preset values, the application-specific integrated circuit 16 of FIG. 1 averages out the even compensation values and the odd compensation values to produce averaged odd-even compensation values. The averaged odd-even compensation values are stored inside the compensation memory unit 18 of FIG. 1 . For example, when one of the even 2×CCD cells and one of the odd 1×CCD cells scan an image pixel, optical data are converted into an even data value=250 and an odd data value=262 via the analog/digital converter. The application-specific integrated circuit 16 of FIG. 1 receives both the even data value and the odd data value. Inside the application-specific integrated circuit 16 of FIG. 1 , a preset value=255 is subtracted from the even value data=250 to produce an even compensation value=−5. Similarly, a preset value=255 is subtracted from the odd value data=262 to produce an odd compensation value=7. Thereafter, the even compensation value and the odd compensation value are averaged ((even compensation value=−5+odd compensation value=7)/2) to produce an averaged odd-even compensation value=1. Finally, the averaged odd-even compensation value is transferred to the compensation memory unit 18 of FIG. 1 . In this embodiment, compensation white is used as color compensation. Hence, the preset value is 255.
After performing the compensation procedure, the scanning device starts to scan an object document. The even 2×CCD cells and the odd 1×CCD cells scan image pixels and the optical data are converted into even data values and odd data values by the analog/digital converter 14 of FIG. 1 . The resultant data values are transferred to the application-specific integrated circuit 16 of FIG. 1 . At this stage, the averaged odd-even compensation value=1 is retrieved from the compensation memory unit 18 of FIG. 1 . After adding the averaged odd-even compensation value to the even data value and the odd data value, a pair of image values is output to the image memory unit 20 of FIG. 1 . The odd and even image values reside in the image memory unit 20 of FIG. 1 until they are required by the input/output interface 22 of FIG. 1 . When such moment arrives, the application-specific integrated circuit 16 of FIG. 1 reads out the pair of image values from the image memory unit 20 of FIG. 1 and sends them to the input/output interface 22 of FIG. 1 .
According to the flow described in FIG. 1 , a flow diagram showing the scanning method for saving some compensation memory is produced in FIG. 4 . As shown in FIG. 4 , step S 400 is executed to provide an even compensation value and an odd compensation value. Step S 402 is executed to average out the even compensation value and the odd compensation value and produce an averaged odd-even compensation value. Finally, step S 404 is executed using the averaged odd-even compensation value to compensate for the values obtained from even pixel position and odd pixel position during a scanning operation.
In this invention, compensation values are split up into odd compensation values and even compensation values. The odd and even compensation values are then averaged to produce an averaged odd-even compensation value. Since a pair of CCD cells uses the same odd-even compensation value after each scanning operation, memory capacity required for compensation data storage is cut in half.
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 reducing memory requirement in the compensation memory unit of a scanner. The method includes providing an even compensation data value and an odd compensation data value and averaging the two to produce an odd-even compensation data value. Only half as much memory space is required to hold the averaged odd-even compensation data values. | 7 |
[0001] This work was funded by the National Science Foundation through Grant Number DMR-9730189, and by the MRSEC program of the National Science Foundation through Grant Number DMR-980595. The government has certain rights in this invention.
FIELD OF THE INVENTION
[0002] The present invention is directed generally to the field of optical trapping techniques. More particularly, the present invention relates to techniques for manipulating particles and fluids using the torques and forces exerted by optical vortex traps.
BACKGROUND OF THE INVENTION
[0003] Optical tweezers use forces exerted by intensity gradients in strongly focused beams of light to trap and selectively move microscopic volumes of matter. Capable of applying precisely controlled forces to particles ranging in size from several to tens of nanometers to tens of micrometers, single optical tweezers have been adopted widely in biological and physical research. Holographic optical tweezers expand upon these capabilities by creating large numbers of optical traps in arbitrary three-dimensional configurations using a phase-modulating diffractive optical element (DOE) to craft the necessary intensity profile. Originally demonstrated with microfabricated diffractive optical elements, holographic optical tweezers have been implemented by encoding computer-designed patterns of phase modulation into the orientation of liquid crystal domains in spatial light modulators. Projecting a sequence of trapping patterns with a spatial light modulator dynamically reconfigures the traps.
[0004] Each photon absorbed by a trapped particle transfers its momentum to the particle and tends to displace it from the trap. If the trapping beam is circularly polarized, then each absorbed photon also transfers one quantum, , of angular momentum to the absorbed particle. The transferred angular momentum causes the trapped particle to rotate in place at a frequency set by the balance between the photon absorption rate and viscous drag in the fluid medium. Laguerre-Gaussian modes of light can carry angular momentum in addition to that due to polarization. Bringing such a Laguerre-Gaussian beam to a diffraction-limited focus creates a type of optical trap known as an optical vortex. In additional to carrying angular momentum, optical vortices have other properties useful for assembling and driving micromachines, for pumping and mixing fluids, for sorting and mixing particles, and for actuating microelectromechanical systems.
SUMMARY OF THE INVENTION
[0005] The present invention describes a practical and general implementation of dynamic holographic optical tweezers capable of producing hundreds and even thousands of independent traps for all manner of materials and applications.
[0006] Unlike conventional micromanipulators, dynamic holographic optical tweezers are highly reconfigurable, operate noninvasively in both open and sealed environments, and can be coupled with computer vision technology to create fully automated systems. A single apparatus thus can be adapted to a wide range of applications without modification. Dynamic holographic optical tweezers have widespread applications in biotechnology. The availability of many independent optical manipulators offers opportunities for deeply parallel high throughput screening, surgical modifications of single cells, and fabrication of wide-spectrum sensor arrays. In materials science, the ability to organize disparate materials into three-dimensional structures with length scales ranging from tens of nanometers to hundreds of micrometers constitutes an entirely new category of fabrication processes with immediate applications to photonics and fabrication of functional nanocomposite materials.
[0007] The applications described herein take advantage of a related method for transferring angular momentum to optically trapped particles. The technique uses computer-generated diffractive optical elements to convert a single beam into multiple traps, which in turn are used to form one or more optical vortices. The present invention involves combining the optical vortex technique with the holographic optical tweezer technique to create multiple optical vortices in arbitrary configurations. The present invention also involves employing the rotation induced in trapped particles by optical vortices to assemble clusters of particles into functional micromachines, to drive previously assembled micromachines, to pump fluids through microfluidics channels, to control flows of fluids through microfluidics channels, to mix fluids within microfluidics channels, to transport particles, to sort particles and to perform other related manipulations and transformations on matter over length scales ranging from roughly 5-10 nm to roughly 100 μm. Several applications and related extensions derive from the properties of optical vortices.
[0008] Other features and advantages of the present invention will become apparent to those skilled in the art from the following detailed description. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the present invention, are given by way of illustration and not limitation. Many changes and modifications within the scope of the present invention may be made without departing from the spirit thereof, and the invention includes all such modifications.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The foregoing advantages and features of the invention will become apparent upon reference to the following detailed description and the accompanying drawings, of which:
[0010] [0010]FIG. 1 is a schematic implementation of dynamic holographic optical tweezers using a reflective liquid crystal spatial light modulator to create multiple laser beams from a single input beam;
[0011] [0011]FIG. 2(A) is a pattern of 26 colloidal silica spheres 1.5 μm in diameter before transformation using dynamic holographic optical tweezers; FIG. 2(B) is the same pattern after 16 steps of the transformation process; and FIG. 2(C) is the final configuration of the pattern after 38 steps of the transformation process;
[0012] [0012]FIG. 3(A) is an image of causing incremental three-dimensional motion with holographic optical tweezers showing thirty-four 0.99 μm diameter silica spheres trapped in a single plane and then displaced by ±5 μm using Eq. (6), wherein the spheres images change in response to their displacement from the focal plane; and FIG. 3(B) shows seven spheres trapped simultaneously in seven different planes using kinoforms calculated with Eq. (7);
[0013] [0013]FIG. 4(A) is an image of a triangular array of optical vortices with a topological charge l=20 created from an equivalent array of tweezers; FIG. 4(B) is an image of colloidal polystyrene spheres 800 nm in diameter trapped in 3×3 square array of l=15 optical vortices; and FIG. 4(C) is an image of a mixed array of optical tweezers (l=0) and optical vortices with l=15 and l=30 in the same configuration as (a), calculated with Eq. (11);
[0014] [0014]FIG. 5 is a schematic diagram of an optical train used for creating a single optical vortex trap from a collimated Gaussian laser beam;
[0015] [0015]FIG. 6 is a photomicrograph of a conventional optical tweezer focused into the same plane as an optical vortex with l=60;
[0016] [0016]FIG. 7 is an illustration of an array of optical vortices with l=15 created by modifying a 3×3 array of conventional holographic optical tweezers using the system described in Eq. (5);
[0017] [0017]FIG. 8(A) is a schematic illustration of a single particle trapped in an optical vortex spinning about its axis and is entrained in a circulating flow of fluid; FIG. 8(B) is a schematic illustration of multiple particles trapped on the rim of an optical vortex and which interact hydrodynamically to collectively rotate about the vortex's center; FIG. 8(C) is an illustration of a ring of colloidal silica spheres 1 μm in diameter dispersed in water and trapped in an optical vortex with l=40; and FIG. 8(D) shows a 3×3 array of optical vortices with l=15 creating and driving rings of 800 nm diameter colloidal polystyrene spheres;
[0018] [0018]FIG. 9(A) schematically shows a spinning particle or a rotating ring of particles in an optical vortex with an entraining circulating fluid flow; FIG. 9(B) shows a schematic superposition of flows driven by multiple spinning particles that can lead to useful fluid transport in microfluidics channels; and FIG. 9(C) shows schematically how reversing the sense of one particle's rotation drives the flow out one of the channels; and
[0019] [0019]FIG. 10 is a schematic representation of optical vortices with alternating positive and negative topological charge transporting particles rapidly along a line.
DETAILED DESCRIPTION OF THE INVENTION
[0020] [0020]FIG. 1 is a schematic implementation of a preferred form of dynamic holographic optical tweezer system 10 using a reflective liquid crystal spatial light modulator 12 to create multiple laser beams from a single input beam. The inset phase grating of the modulator 12 is {fraction (1/25)} of the hologram φ({right arrow over (ρ)}) encoding a 20×20 array of traps, with white regions corresponding to local phase shifts of 2π radians and back to 0. The beams 14 formed by the diffractive optical element are relayed by a telescope to the back aperture of a high-numerical-aperture objective lens 18 which focuses them into optical traps. The inset video micrographs show the diffraction-limited focal points reflected off a mirrored surface placed in the object plane, as well as 200 colloidal polystyrene spheres 800 nm in diameter trapped in the pattern.
[0021] Holographic optical tweezers make use of the same physical principles as concentrated optical tweezers. A dielectric particle approaching the optical tweezer system is polarized by the light's electric field. The resulting electric dipole is drawn up intensity gradients to the focus where it is trapped. This optical gradient force competes with radiation pressure which tends to displace the trapped particle along the beam's axis. Stable trapping is possible only if the focused beam's axial intensity gradient is large enough. For this reason, optical tweezers are conventionally constructed around microscope objectives with large numerical apertures and minimal aberrations.
[0022] An optical trap may be placed anywhere within the objective lens' focal volume by appropriately selecting the input beam's propagation direction and degree of collimation. For example, the collimated beam 20 entering the back aperture of the infinity-corrected objective lens 18 comes to a focus in the center of the lens' focal plane while another beam entering at an angle comes to a focus off-center. A slightly diverging beam focuses downstream of the focal plane while a converging beam focuses upstream. Multiple beams entering the lens' input pupil simultaneously each form optical traps in the focal volume, each at a location determined by its angle of incidence. The holographic optical tweezer technique uses a phase modifying diffractive optical element to impose the phase pattern for multiple beams traveling in disparate directions onto the wavefront of a single input beam, thereby transforming the single beam into multiple traps.
[0023] In the implementation depicted in FIG. 1, the diffractive optical element's function is performed by a Hamamatsu X7550 phase-only spatial light modulator 22 (SLM) capable of encoding 256 phase levels ranging from 0 to 2π radians onto light of wavelength λ=532 nm at each 40 μm phase pixel in a 480×480 array. The phase shift imposed at each pixel is specified through a computer interface with an effective refresh rate of 3 Hz for the entire array. In this particular preferred implementation, the focusing element is a Zeiss 100×NA 1.4 oil immersion objective mounted on an Axiovert S100 TV microscope 24 . A dichroic mirror 26 reflects laser light into the objective lens 18 while allowing images of the trapped particles to pass through to a video camera 26 . When combined with a 2.5×widefield video eyepiece, the optical train offers a 78×52 μm 2 field of view.
[0024] Modulating only the phase of the input beam is enough to establish any pattern of optical traps because trapping relies only on the beams' intensities and not on their relative phases. Amplitude modulations are not preferred because they would divert light away from the traps and diminish their effectiveness. Phase-only diffraction gratings used for establishing desired intensity patterns are known as kinoforms. The practical difficulty of identifying the phase modulation which best encodes a particular pattern of traps has limited previous holographic optical tweezer implementations to planar trapping patterns or very simple three-dimensional arrangements of just a few particles on fewer planes. The resulting traps, furthermore, were only appropriate for dielectric particles in low-dielectric media, and not for the more general class of materials including metals and particles made of absorbing, reflecting, or low-dielectric-constant materials.
[0025] The following discussion specifies one preferred method for calculating the kinoforms required for the applications considered in the invention. Generally, an incident laser beam's electric field in the diffractive optical element plane, E 0 ({right arrow over (ρ)})=A 0 ({right arrow over (ρ)})exp(iψ), to have a constant phase ψ=0 and unit intensity in the diffractive optical element plane: ∫ Ω |A 0 ({right arrow over (ρ)})| 2 d 2 ρ=1. In this case, {right arrow over (ρ)} denotes a position in the diffractive optical element's aperture Ω. A 0 ({right arrow over (ρ)}) is the real-valued amplitude profile of the input beam. The field's polarization vector is omitted without loss of generality with the understanding that polarization effects operate independently and in coordination with those considered here. The diffractive optical element then imposes onto the input beam's wavefront the phase profile φ 0 ({right arrow over (ρ)}), encoding the desired pattern of outgoing beams. These beams then are transferred by relay optics, depicted schematically in FIG. 1 as the simple telescope 16 , to the objective lens 18 which forms them into traps.
[0026] The electric field ∈ j =α j exp(iφ j ) at each of the discrete traps is related to the electric field in the plane of the spatial light modulator by a generalized Fourier transform:
E ( ρ -> ) = A ( ρ -> ) exp ( ϕ ( ρ -> ) ) ( 1 ) = ∑ j = 1 N ∫ ∈ j δ ( r -> , p -> ) exp ( 2 π r -> · ρ -> λ f ) 3 r ( 2 ) = ∑ j = 1 N ∈ j K j - 1 ( r -> j , ρ -> ) exp ( 2 π r -> · ρ -> λ f ) 3 r , ( 3 )
[0027] The kernel K j ({right arrow over (r)}, {right arrow over (ρ)}) can be used to transform the j-th trap from a conventional tweezer into another type of trap, and K j −1 is its inverse. For conventional optical tweezers, K j =1.
[0028] If A({right arrow over (ρ)}) were identical to the input laser beam's amplitude profile, A 0 ({right arrow over (ρ)}), then φ({right arrow over (ρ)}) would be the kinoform encoding the desired array of traps. Unfortunately, this is rarely the case. More generally, the spatially varying discrepancies between A({right arrow over (ρ)}) and A 0 ({right arrow over (ρ)}) direct light away from the desired traps and into ghosts and other undesirable artifacts. Although such composition of kinoforms is expedient, it works poorly for all but the simplest and most symmetric patterns. Nevertheless, it can serve as the basis for an iterative approximation scheme capable of computing highly efficient estimates for the ideal kinoform φ 0 ({right arrow over (ρ)}).
[0029] Following one particular approach, the phase φ({right arrow over (ρ)}) is calculated with Eq. (3) to be an estimate φ n ({right arrow over (ρ)}) for the desired kinoform and use this to calculate the fields at the trap positions given the actual laser profile:
∈ j ( n ) = ∫ Ω A 0 ( ρ -> ) exp ( i ϕ n ( ρ -> ) ) K j ( r ⇀ j , ρ -> ) exp ( - 2 π r -> · ρ -> λ f ) 2 ρ . ( 4 )
[0030] The index n refers to the n-th iterative approximation to φ 0 ({right arrow over (ρ)}). The fraction Σ j |∈ j (n) | 2 =Σ j |α j (n) | 2 of the incident power actually delivered to the traps is a useful measure of the kinoform's efficiency.
[0031] The classic Gerchberg-Saxton algorithm replaces the amplitude α j (n) in this estimate with the desired amplitude α j , leaving the corresponding phase φ j (n) unchanged, and solves for estimate φ n+1 ({right arrow over (ρ)}) using Eq. (3). This approach suffers from slow and nonmonotonic convergence, however. The alternate replacement scheme is:
α j ( n + 1 ) = [ ( 1 - a ) + a α j α j ( n ) ] α j ( 5 )
[0032] Which leads to rapid monotonic convergence for α≈0.5. The resulting estimate for φ 0 ({right arrow over (ρ)}) then can be discretized and transmitted to the spatial light modulator to establish a trapping pattern. In cases where the spatial light modulator offers only a few discrete phase levels, discretization can be incorporated into each iteration to minimize the associated error. In all of the examples discussed below, the algorithm yields kinoforms with theoretical efficiencies exceeding 80% in two or three iterations.
[0033] Previously published techniques for computing holographic optical tweezer kinoforms utilize fast Fourier transforms to optimize the field over the entire trapping plane. These techniques achieve theoretical efficiencies exceeding 90%. However, such methods are appropriate only for two-dimensional patterns of conventional optical tweezers. The discrete transforms adopted in accordance with the preferred form of the present invention permit the encoding of more general patterns of optical tweezers as well as mixed arrays of different types of traps. Furthermore, the approach of the present invention can be implemented efficiently because discrete transforms are calculated only at the actual trap locations.
[0034] [0034]FIG. 2(A) shows 26 colloidal silica spheres 0.99 μm in diameter suspended in water and trapped in a planar pentagonal pattern of optical tweezers. Replacing this kinoform with another in which the taps are slightly displaced causes the spheres to hop into the next trapping pattern. Projecting a sequence of trapping patterns deterministically translates the spheres into an entirely new configuration. FIG. 2(B) shows the same spheres after 15 such hops and FIG. 2(C) after 30 such steps.
[0035] Comparable motion in the plane also can be accomplished by rapidly scanning a single tweezer through a sequence of discrete locations, thereby creating a time-shared trapping pattern. Continuous illumination of holographic optical traps offer several advantages, however. The lower peak intensities in continuous traps minimize damage to sensitive samples. Holographic optical tweezer patterns also can be more extensive than time-shared arrays which periodically release and retrieve each trapped particle.
[0036] Furthermore, dynamic holographic optical tweezers are not limited to planar motion. If the laser beam illuminating the spatial light modulator were slightly diverging, then the entire pattern of traps would come to a focus downstream of the focal plane. Such divergence can be introduced with a Fresnel lens, encoded as a phase grating with:
ϕ z ( ρ -> ) = 2 πρ 2 M λ z mod2 π , ( 6 )
[0037] where z is the desired displacement of the optical traps relative to the focal plane in an optical train with axial magnification M. In the above case, the modulo operator is understood to discretize the continuous phase profile for an optimal implementation on the phase-shifting optical element 15 . Rather than placing a separate Fresnel lens into the input beam, the same functionality can be obtained by adding the lens' phase modulation to the existing kinoform: [φ 0 ({right arrow over (ρ)})+φ z ({right arrow over (ρ)})]mod2π. FIG. 3(A) shows a typical array of optical tweezers collectively displaced out of the plane in this manner. The accessible range of out-of-plane motion according to the present invention is ±10 μm.
[0038] Instead of being applied to the entire trapping pattern, separate lens functions can be applied to each trap individually by including the kernels
K j z ( r -> j , ρ -> ) = exp ( 2 πρ 2 M λz j ) ( 7 )
[0039] in Eqs. (3) and (4). FIG. 3(B) shows seven spheres simultaneously positioned in seven different planes in this way.
[0040] [0040]FIG. 5 shows a conventionally-known method for converting a Gaussian beam of light into a Laguerre-Gaussian beam useful for forming optical vortices. As shown in FIG. 5, the Gaussian beam 10 propagates from the left to the right. When viewed in a cross-section 12 , the Gaussian beam 10 has a uniform and constant phase, as indicated schematically in an inset 40 . After passing through an appropriately designed diffractive optical element 15 , the Gaussian beam 10 acquires a phase which precesses around the optical axis, and thus is converted into a Laguerre-Gaussian beam. When viewed at a cross-section 18 , the phase varies across the wavefront as shown in inset 50 . The modified beam then is reflected by a mirror 20 into the back aperture of a strongly converging focusing element 25 . This strongly converging focusing element 25 brings the beam 10 to a focus 30 . The focus 30 is the location of the optical vortex.
[0041] The diffractive optical element 15 is preferably chosen from the class of phase modifying diffractive optical elements, rather than from the class of amplitude or mixed phase-amplitude diffractive optical elements. A diffractive optical element which modifies the amplitude of the beam 10 must reduce its amplitude, thereby reducing the intensity and lowering the overall efficiency of the optical train. A phase-only diffractive optical element, on the other hand, can operate on the beam 10 without reducing the intensity. In the case of a phase-only diffractive optical element, the diffractive optical element needs to convert a TEM 00 Gaussian beam into a Laguerre-Gaussian beam of topological charge l and thus must shift the beam's phase by an amount:
φ l ({right arrow over (ρ)})= lθmod 2π (8)
[0042] In this situation, the center (r=0) of the phase pattern is aligned with the axis of the beam.
[0043] A practical phase hologram, such as a practical phase hologram implemented using a phase-shifting spatial light modulator, cannot implement any arbitrary amount of phase shift. Rather, such practical phase holograms are typically designed to implement discrete values of a phase shift between 0 and a maximum phase shift of 2π radians. In such an example, the required phase shift is modified to account for the following particular consideration:
φ q ( {right arrow over (r)} )= qθmod 2π (9)
[0044] A diffractive optical element of the type described above creates an approximation to a Laguerre-Gaussian beam coaxial with the initial Gaussian beam. Such an arrangement is undesirable in some circumstances, and deflecting the Laguerre-Gaussian beam away from the initial input beam can be preferable. In such a case, the desired phase profile can be modified to:
φ q ( {right arrow over (r)} )=( {right arrow over (k)}·{right arrow over (r)}+lθ ) mod 2π (10)
[0045] In the above situation, the angular deflection of the Laguerre-Gaussian beam is given by sin −1 (kλ), with k=|{right arrow over (k)}|, for light of wavelength λ. This phase function is capable of creating a single displaced optical vortex from a single input Gaussian beam.
[0046] [0046]FIG. 6 is a photomicrograph of a conventional optical tweezer focused into the same plane as an optical vortex with l=60. The apparently nonuniform intensity along the rim of the vortex is a polarization-dependent artifact of the imaging system and not an inherent property of the vortex or of its implementation.
[0047] The mirror 20 as shown in FIG. 5 may be chosen such that light collected by the focusing element passes through the mirror 20 to an imaging system. For example, a dichroic mirror 20 can be chosen to reflect the wavelength of laser light while allowing other wavelengths to pass therethrough for imaging. If the mirror 20 is only partially reflective, some of the laser light scattered by a sample at a point 30 can pass back through the mirror to create an image of the optical vortex itself. FIG. 6 shows such a picture with the point-like focus of a conventional optical tweezer contrasted with the diffraction-limited ring-focus of an optical vortex of l=60.
[0048] Notably, the largest topological charge reported previously has l=3 and was implemented with a photolithographically fabricated diffractive optical element. Optical vortices implemented in accordance with the present invention, however, have included topological charges exceeding l=160 using a dynamic spatial light modulator. Some useful and interesting physical effects which form the basis of the present invention only are manifested for high-charge optical vortices and so would not have been observed using conventional techniques.
[0049] It has been previously suggested that an alternative technique for reconfiguring beams of light with a spatial light modulator also is capable of creating optical vortices. The alternative is deficient, however, because the optical train does not create the phase profile of an optical vortex and therefore cannot implement the optical vortices' characteristic and useful properties. Instead, the alternative approach simply shapes the intensity of the trapping beam into an annulus. Such a shaped beam would come to a bright focus and share the properties of conventional optical tweezers.
[0050] Previous, conventional implementations have produced only single optical vortices in fixed positions. By contrast, the implementation according to the present invention builds upon the holographic optical tweezer technique and permits the creation of arbitrary three-dimensional arrangements of multiple optical vortices, each with its own specified topological charge. When implemented with a computer-addressable spatial light modulator, the same technique permits dynamical reconfiguration of the ensemble of vortices.
[0051] Optical vortices have at least two notable properties. Because all phases are present along the circumference of a Laguerre-Gaussian beam, destructive interference cancels the beam's intensity along its axis, all the way to the focus. Optical vortices thus have dark centers roughly λ{square root}{square root over (2l)} across and are useful for trapping reflecting, absorbing or low-dielectric particles or low-dielectric particles not compatible with conventional optical tweezers. Each photon in a Laguerre-Gaussian beam also carries angular momentum l , independent of its polarization. A particle absorbing such photons while trapped in an optical vortex therefore experiences a torque proportional to the rate at which the particle absorbs photons and the beam's topological charge l. Optical vortices are useful, therefore, for driving motion at small length scales, for example in microelectromechanical systems.
[0052] Applying φ l ({right arrow over (ρ)}). to a kinoform encoding an array of optical tweezers yields an array of identical optical vortices, as shown in FIG. 4(A). In this case, the light from the trap array is imaged directly by reflection off a mirrored surface in the microscope's focal plane. Light from the focused optical vortices is imaged from a mirrored surface in the sample plane. The inset shows a more detailed view of one vortex's structure. FIG. 4(B) shows multiple colloidal particles trapped on the bright circumferences of a 3×3 array of l=15 vortices. Multiple particles trapped in arrays of optical vortices have remarkable cooperative behavior, particularly for large values of the topological charge l.
[0053] The vortex-forming phase function also can be applied to individual traps through:
K j v ( {right arrow over (r)} j ,{right arrow over (ρ)})= exp ( il j θ), (11)
[0054] as demonstrated in the mixed array of optical tweezers and optical vortices shown in FIG. 4(C). K v can be combined with K L to produce three-dimensional arrays of vortices. Such heterogeneous trapping patterns are useful for organizing disparate materials into hierarchical three-dimensional structures and for exerting controlled forces and torques on extended dynamical systems.
[0055] Appropriately phased linear combinations of optical vortices and conventional tweezers have been shown to operate as optical bottles and controlled rotators. Such composite traps also can be synthesized with straightforward modifications of the algorithms discussed here. Still other phase profiles can impart new functionality. For example, the axicon profile φ a ({right arrow over (ρ)})=γρ converts a Gaussian beam into an approximation of a Bessel beam. Such beams come to a diffractionless focus over a range which can extend to several microns. The resulting axial line traps are useful for guiding particles in three dimensions, for aligning rod-like and elliptical samples, and for creating uniform stacks of particles. Other generalizations follow naturally with virtually any mode of light having potential applications.
[0056] Prior discussions and implementations of optical vortices emphasized the potential utility for driving microscopic machines through the transfer of torque from single optical vortices. In these cases, the use of single optical vortices of low topological charge was emphasized. The following applications take advantage of one or more properties of optical vortices and optical vortex arrays created with the holographic optical tweezer (HOT) technique.
[0057] Prior applications have used torque exerted by circularly polarized light to rotate individual components of micromachines. Using optical vortices to drive circular motion offers several advantages. By increasing the amount of angular momentum transferred per photon of absorbed light, the topological charge l reduces the power required to achieve a desired amount of torque. This phenomenon is beneficial for minimizing undesirable heating due to absorbed light as well as for reducing the power requirements and cost of the laser. Transferring the angular momentum to the rim of a micromachined gear also improves efficiency because the centers of such devices often serve as axles, bearings, or other stationary components. Light absorbed at such points contributes only to heating and is otherwise wasted.
[0058] Because of the difficulty of driving even one micromachined gear with other available techniques using conventional techniques, conventional microelectromechanical devices (MEMs) are designed to be driven at just one point. The availability of multiple independent vortices in a holographic optical tweezer system facilitates distributed driving in MEMs systems. Supplying torque to multiple stages in a complex mechanical system improves efficiency, reduces wear and reduces the requirements on the maximum torque any one component must withstand.
[0059] Optical vortices transfer torque to illuminated particles. Additionally, optical vortices also act as optical traps. Dielectric particles attracted to a bright rim of an optical vortex can be trapped in three dimensions, similar to the trapping action in an ordinary optical tweezer. Particles trapped in a vortex, however, spin on their axis at a rate governed by a balance between optical absorption and viscous drag. The spinning particles entrain flows in the surrounding fluid, and these flows can be used for several purposes.
[0060] If the circumference of an optical vortex's rim is larger than the diameter of a particle, then several dielectric particles can be trapped simultaneously on the rim, each spinning on its axis. One particle spinning on the rim of an optical vortex will not spontaneously translate through the surrounding fluid. Hydrodynamic coupling among neighboring trapped particles, however, leads the entire assembly of particles to rotate around the center of the vortex. The rates of spinning and rotation can be controlled over a wide range by changing the laser's intensity while leaving all other control parameters fixed. FIG. 8(C) shows such a ring of particles created with a l=60 optical vortex. The images of the individual spheres in FIG. 8(C) are blurred because the ring rotates at roughly 100 Hz.
[0061] The holographic optical tweezer technique can create multiple optical vortices in virtually any desired configuration. For example, FIG. 8(D) shows a 3×3 array of co-rotating rings of particles trapped in l=15 optical vortices. The array of vortices shown in FIG. 7 was used to create this micromachine. Interactions among such rings can produce cooperative effects not possible with one ring, just as trapping multiple particles in a single vortex leads to new effects not seen with a single trapped particle.
[0062] One of the principal advantages of the approach to assembling and driving micromachines described herein is that it operates with no moving parts. All of the assembly is accomplished by static optical gradient forces, and all of the motion is driven by the angular momentum inherent in the light's topological charge.
[0063] The flow outside a single spinning particle or a ring of particles can be used to pump fluids through small channels. FIG. 10 schematically shows a typical implementation, with four centers of rotation entraining flow in a closed loop. Regarding the self-assembled micromachines, this application of optical vortices shown in FIG. 6 has the advantage of operating non-invasively on a closed system while relying on no moving parts. Indeed, steady-state pumping can be achieved with a single static diffractive optical element in a holographic optical tweezer optical train.
[0064] Having established a pumping pattern such as the example in FIG. 9(B), reversing the sense of rotation of one of the vortices results in a reconfigured pumping pattern which redirects the fluid flow. This reconfigured pattern is shown in FIG. 9(C). In FIG. 9(B), the four trapped particles (or rings) cooperate to pump fluid through a closed loop. This dynamical reconfiguration of flows can be performed in real time by changing the diffractive optical element projected in the holographic optical tweezer system.
[0065] Rotating rings of particles, such as in the examples shown in FIGS. 8 (C) and 8 (D), permit the entrainment of very complicated flow patterns. These flow patterns can be used to mix fluids in volumes ranging from a few hundred nanometers across to a few hundred micrometers across. Such mixing is useful in lab-on-a-chip applications for which the laminar flow in microfluidics systems generally precludes mixing.
[0066] Holographic optical tweezers are capable of placing optical vortices in virtually any desired configuration and can alternate among sequences of vortex patterns. For example, the schematic diagram shown in FIG. 10 shows three overlapping optical vortices whose topological charge alternates sign. It should be noted that, if necessary, the different types of vortices can be turned on and off alternately to produce deterministic transport favoring collections of particles of a particular size. A single particle subjected to such an intensity field will spin in place. Multiple particles, however, are driven along the rim of each vortex. Using the holographic optical tweezer technique, the vortices can be placed tangent to each other. Particles reaching the intersection will find their spin suppressed and so can be pushed by their neighbors into the vortex with alternate sense rotation. Once two or more particles have been pushed over, the collection will rotate along the rim of the second vortex, and so on. This technique allows for the rapid transport of particles along simple or complicated trajectories, with no moving parts, using a single static hologram.
[0067] Alternately turning on and off the positive and negative vortices opens up additional possibilities for dynamically selecting particles on the basis of their transit times around the vortices' rims. Such a procedure may be used as the basis of a particle fractionation technique.
[0068] It should be understood that the above description of the invention and specific examples and embodiments, while indicating the preferred embodiments of the present invention are given by demonstration and not limitation. Many changes and modifications within the scope of the present invention may be made without departing from the spirit thereof and the present invention includes all such changes and modifications. | A method for creating large numbers of high-quality optical traps in arbitrary three-dimensional configurations and dynamically reconfiguring the traps under computer control. The method uses computer-generated diffractive optical elements to convert one or more optical tweezers into one or more optical vortices. The method involves combining the optical vortex technique with the holographic optical tweezer technique to create multiple optical vortices in arbitrary configurations. The method also involves employing the rotation induced in trapped particles by optical vortices to assemble clusters of particles into functional micromachines, to drive previously assembled micromachines, to pump fluids through microfluidics channels, to control flows of fluids through microfluidics channels, to mix fluids within microfluidics channels, to transport particles, to sort particles and to perform other related manipulations and transformations on matter over length scales | 6 |
This application incorporates by reference in their entireties U.S. patent application Ser. No. 13/281,718, filed Oct. 26, 2011, which issued as U.S. Pat. No. 8,885,149 on Nov. 11, 2014, and U.S. provisional application 61/419,191, filed Dec. 2, 2010.
BACKGROUND
1. Field of Invention
The invention generally relates to lithography, and more particularly to support structures and arrangements for patterning devices.
2. Related Art
Lithography is widely recognized as a key process in manufacturing integrated circuits (ICs) as well as other devices and/or structures. A lithographic apparatus is a machine, used during lithography, which applies a desired pattern onto a substrate, such as onto a target portion of the substrate. During manufacture of ICs with a lithographic apparatus, a patterning device, which is alternatively referred to as a mask or a reticle, is typically used to generate a circuit pattern to be formed on an individual layer in an IC. This pattern is transferred onto the target portion (for example, comprising part of, one, or several dies) of the substrate (for example, a silicon wafer). Typically, the pattern is transferred to a layer of radiation-sensitive material (for example, resist) provided on the substrate by imaging the pattern onto the radiation-sensitive material. A typical substrate may contain many such target portions that are adjacent to one another and are successively patterned.
Known lithographic apparatus include steppers, in which each target portion is irradiated by exposing an entire pattern onto the target portion at one time, and scanners, in which each target portion is irradiated by scanning the pattern through a radiation beam in a given direction (the “scanning” direction) while synchronously scanning the substrate parallel or anti-parallel to this direction. It is also possible to transfer the pattern from the patterning device to the substrate by imprinting the pattern onto the substrate.
To increase production rate of scanned patterns, a patterning device, for example, a mask or reticle, is scanned at constant velocity, for example, 3 meters/second across a projection lens, back and forth along a scan direction. Therefore, starting from rest, the reticle quickly accelerates to reach the scan velocity, then at the end of the scan, it quickly decelerates to zero, reverses direction, and accelerates in the opposite direction to reach the scan velocity. The acceleration/deceleration rate is, for example, 15 times the acceleration of gravity. There is no inertial force on the patterning device during the constant velocity portion of the scan. However, the large inertial force encountered during the acceleration and deceleration portions of the scan, for example, approximately 60 Newtons (=0.4 kg of patterning device mass×150 m/sec2 of acceleration), can cause the patterning device to slip. Such slippage can result in a misaligned device pattern on a substrate.
Attempts to solve patterning device slippage include using a clamp, such as a vacuum system, to hold the patterning device in place and/or using a friction coating to increase friction between the patterning device and the clamp. However, ever increasing production rates demand ever faster direction reversals and, therefore, higher accelerations have reduced the benefits of these solutions. With clamps, the normal force between the patterning device and the clamp generates a friction force during the acceleration and deceleration portions of the scan. The friction force holds the patterning device in place during these portions. However, with vacuum clamps, the friction force is limited by the maximum differential pressure between atmosphere and the vacuum, which now is only about 1 bar. Further, the small surface area of patterning devices in contact with the clamps limits the normal force that can be generated by the clamps. Currently, the highest friction coefficient of suitable friction coatings is only approximately 0.25.
SUMMARY
Given the foregoing, improved methods and systems are needed that provide an anti-slip solution for patterning devices that can function under high acceleration with minimal additional mass or controls.
An embodiment of the invention provides a patterning device transport system comprising a holding system having a support device, a holding device, and magnetostrictive actuator, and a support transport device configured to move and coupled to the support device. The holding device is configured to releasably couple a patterning device to the support device, and the magnetostrictive actuator is configured to provide a force to the patterning device. The support transport device moves the support device concurrently with the magnetostrictive actuator providing the force to the patterning device such that patterning device slip during the movement of the support device is substantially eliminated.
Another embodiment of the invention provides a patterning device stage system for a lithographic apparatus, comprising a stage configured to releasably couple a patterning device to the stage, a stage control system configured to control movement of the stage, and a magnetostrictive control system configured to apply a force to the patterning device.
A further embodiment of the present invention provides a method for reducing patterning device slip during movement of a patterning device stage, comprising supporting a patterning device with a support device; concurrently holding the patterning device to the support device with a holding device; moving the support device using a first moving device; and applying a force to the patterning device using a magnetostrictive actuator concurrently with moving the support device using the first moving device.
Features and advantages of the invention, as well as the structure and operation of various embodiments of the invention, are described in detail below with reference to the accompanying drawings. The invention is not limited to the specific embodiments described herein. Such embodiments are presented herein for illustrative purposes only. Additional embodiments will be apparent to persons skilled in the relevant art(s) based on the teachings contained herein.
BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES
The accompanying drawings, which are incorporated herein and form part of the specification, illustrate the present invention and, together with the description, further serve to explain the principles of the invention and to enable a person skilled in the relevant art(s) to make and use the invention.
FIG. 1A is a schematic illustration of a reflective lithographic apparatus according to an embodiment of the invention.
FIG. 1B is a schematic illustration of a transmissive lithographic apparatus according to an embodiment of the invention.
FIG. 2 is a schematic illustration of a patterning device transport system with anti-slip control, according to an embodiment of the invention.
FIG. 3 is a schematic illustration of a top view of a patterning device transport system without anti-slip control according to an embodiment of the invention.
FIG. 4 is a schematic illustration of a partial side view of a patterning device transport system with anti-slip control according to an embodiment of the invention.
FIG. 5 is a schematic illustration of a stage system with anti-slip control according to an embodiment of the invention.
FIG. 6 is a flowchart illustrating a method for patterning device transport with anti-slip control according to an embodiment of the invention.
FIG. 7 is a flow chart illustrating a method for loading a patterning device on a transport system with anti-slip control according to an embodiment of the invention.
FIGS. 8A-8D are schematic illustrations of a partial side view of a patterning device transport system with anti-slip control at various steps of a method for loading a patterning device on a transport system according to an embodiment of the invention.
FIG. 9 is a schematic illustration of a stage system with anti-slip control according to an embodiment of the invention.
FIG. 10 is a schematic illustration of a partial side view of a patterning device transport system with anti-slip control according to an embodiment of the invention.
Various features and advantages of the invention will become more apparent from the detailed description set forth below, read in conjunction with the drawings, in which like reference characters identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. Generally, the drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number.
DETAILED DESCRIPTION
Embodiments of the invention are directed to a patterning device transport system with anti-slip control. This specification discloses one or more embodiments that incorporate the features of the present invention. The disclosed embodiment(s) merely exemplify the invention. The scope of the invention is not limited to the disclosed embodiment(s). The invention is defined by the claims appended hereto.
The embodiment(s) described, and references in the specification to “one embodiment,” “an embodiment,” “an example embodiment,” etc., indicate that the embodiment(s) described can include a particular feature, structure, or characteristic, but every embodiment can not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is understood that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
Embodiments of the invention may be implemented in hardware, firmware, software, or any combination thereof. Embodiments of the present invention can also be implemented as instructions stored on a machine-readable medium, which can be read and executed by one or more processors. A machine-readable medium can include any mechanism for storing or transmitting information in a form readable by a machine (for example, a computing device). For example, a machine-readable medium can include the following: read-only memory (ROM); random access memory (RAM); magnetic disk storage media; optical storage media; and, flash memory devices. Further, firmware, software, routines, instructions can be described herein as performing certain actions. However, it should be appreciated that such descriptions are merely for convenience and that such actions in fact result from computing devices, processors, controllers, or other devices executing the firmware, software, routines, instructions, etc.
FIG. 1A is a schematic illustration of a reflective lithographic apparatus 100 in which embodiments of the present invention may be implemented. FIG. 1B is a schematic illustration of a transmissive lithographic apparatus 100 ′ in which embodiments of the present invention may be implemented. Lithographic apparatus 100 and lithographic apparatus 100 ′ each include the following: an illumination system (illuminator) IL configured to condition a radiation beam B (for example, DUV or EUV radiation); a support structure (for example, a mask table) MT configured to support a patterning device (for example, a mask, a reticle, or a dynamic patterning device) MA and connected to a first positioner PM configured to accurately position the patterning device MA; and, a substrate table (for example, a wafer table) WT configured to hold a substrate (for example, a resist coated wafer) W and connected to a second positioner PW configured to accurately position the substrate W. Lithographic apparatuses 100 and 100 ′ also have a projection system PS configured to project, through a lens system L, a pattern imparted to the radiation beam B by patterning device MA onto a target portion (for example, comprising one or more dies) C of the substrate W. In lithographic apparatus 100 , the patterning device MA and the projection system PS are reflective. In lithographic apparatus 100 ′, the patterning device MA and the projection system PS are transmissive.
The illumination system IL may include various types of optical components, such as refractive, reflective, magnetic, electromagnetic, electrostatic, or other types of optical components, or any combination thereof, for directing, shaping, or controlling the radiation B.
The support structure MT holds the patterning device MA in a manner that depends on the orientation of the patterning device MA, the design of the lithographic apparatuses 100 and 100 ′, and other conditions, such as whether or not the patterning device MA is held in a vacuum environment. The support structure MT may use mechanical, vacuum, electrostatic, or other clamping techniques to hold the patterning device MA. The support structure MT can be a frame or a table, for example, which can be fixed or movable, as required. The support structure MT can ensure that the patterning device is at a desired position, for example, with respect to the projection system PS.
The term “patterning device” MA should be broadly interpreted as referring to any device that can be used to impart a radiation beam B with a pattern in its cross-section, such as to create a pattern in the target portion C of the substrate W. The pattern imparted to the radiation beam B can correspond to a particular functional layer in a device being created in the target portion C, such as an integrated circuit.
The patterning device MA may be transmissive (as in lithographic apparatus 100 ′ of FIG. 1B ) or reflective (as in lithographic apparatus 100 of FIG. 1A ). Examples of patterning devices MA include reticles, masks, programmable mirror arrays, and programmable LCD panels. Masks are well known in lithography, and include mask types such as binary, alternating phase shift, and attenuated phase shift, as well as various hybrid mask types. An example of a programmable mirror array employs a matrix arrangement of small mirrors, each of which can be individually tilted so as to reflect an incoming radiation beam in different directions. The tilted mirrors impart a pattern in the radiation beam B which is reflected by the mirror matrix.
The term “projection system” PS can encompass any type of projection system, including refractive, reflective, catadioptric, magnetic, electromagnetic and electrostatic optical systems, or any combination thereof, as appropriate for the exposure radiation being used, or for other factors, such as the use of an immersion liquid or the use of a vacuum. A vacuum environment can be used for EUV or electron beam radiation since other gases can absorb too much radiation or electrons. A vacuum environment can therefore be provided to the whole beam path with the aid of a vacuum wall and vacuum pumps.
Lithographic apparatus 100 and/or lithographic apparatus 100 ′ can be of a type having two (dual stage) or more substrate tables (and/or two or more mask tables) WT. In such “multiple stage” machines, the additional substrate tables WT can be used in parallel, or preparatory steps can be carried out on one or more tables while one or more other substrate tables WT are being used for exposure.
Referring to FIGS. 1A and 1B , the illuminator IL receives a radiation beam from a radiation source SO. The source SO and the lithographic apparatuses 100 , 100 ′ can be separate entities, for example, when the source SO is an excimer laser. In such cases, the source SO is not considered to form part of the lithographic apparatuses 100 or 100 ′, and the radiation beam B passes from the source SO to the illuminator IL with the aid of a beam delivery system BD (in FIG. 1B ) including, for example, suitable directing mirrors and/or a beam expander. In other cases, the source SO can be an integral part of the lithographic apparatuses 100 , 100 ′—for example when the source SO is a mercury lamp. The source SO and the illuminator IL, together with the beam delivery system BD, if required, can be referred to as a radiation system.
The illuminator IL can include an adjuster AD (in FIG. 1B ) for adjusting the angular intensity distribution of the radiation beam. Generally, at least the outer and/or inner radial extent (commonly referred to as “σ-outer” and “σ-inner,” respectively) of the intensity distribution in a pupil plane of the illuminator can be adjusted. In addition, the illuminator IL can comprise various other components (in FIG. 1B ), such as an integrator IN and a condenser CO. The illuminator IL can be used to condition the radiation beam B to have a desired uniformity and intensity distribution in its cross section.
Referring to FIG. 1A , the radiation beam B is incident on the patterning device (for example, mask) MA, which is held on the support structure (for example, mask table) MT, and is patterned by the patterning device MA. In lithographic apparatus 100 , the radiation beam B is reflected from the patterning device (for example, mask) MA. After being reflected from the patterning device (for example, mask) MA, the radiation beam B passes through the projection system PS, which focuses, using lens system L, the radiation beam B onto a target portion C of the substrate W. With the aid of the second positioner PW and position sensor IF 2 (for example, an interferometric device, linear encoder, or capacitive sensor), the substrate table WT can be moved accurately (for example, so as to position different target portions C in the path of the radiation beam B). Similarly, the first positioner PM and another position sensor IF 1 can be used to accurately position the patterning device (for example, mask) MA with respect to the path of the radiation beam B. Patterning device (for example, mask) MA and substrate W can be aligned using mask alignment marks M 1 , M 2 and substrate alignment marks P 1 , P 2 .
Referring to FIG. 1B , the radiation beam B is incident on the patterning device (for example, mask MA), which is held on the support structure (for example, mask table MT), and is patterned by the patterning device. Having traversed the mask MA, the radiation beam B passes through the projection system PS, which focuses the beam onto a target portion C of the substrate W. With the aid of the second positioner PW and position sensor IF (for example, an interferometric device, linear encoder, or capacitive sensor), the substrate table WT can be moved accurately (for example, so as to position different target portions C in the path of the radiation beam B). Similarly, the first positioner PM and another position sensor (not shown in FIG. 1B ) can be used to accurately position the mask MA with respect to the path of the radiation beam B (for example, after mechanical retrieval from a mask library or during a scan).
In general, movement of the mask table MT can be realized with the aid of a long-stroke module (coarse positioning) and a short-stroke module (fine positioning), which form part of the first positioner PM. Similarly, movement of the substrate table WT can be realized using a long-stroke module and a short-stroke module, which form part of the second positioner PW. In the case of a stepper (as opposed to a scanner), the mask table MT can be connected to a short-stroke actuator only or can be fixed. Mask MA and substrate W can be aligned using mask alignment marks M 1 , M 2 , and substrate alignment marks P 1 , P 2 . Although the substrate alignment marks (as illustrated) occupy dedicated target portions, they can be located in spaces between target portions (known as scribe-lane alignment marks). Similarly, in situations in which more than one die is provided on the mask MA, the mask alignment marks can be located between the dies.
The lithographic apparatuses 100 and 100 ′ can be used in at least one of the following modes:
1. In step mode, the support structure (for example, mask table) MT and the substrate table WT are kept essentially stationary, while an entire pattern imparted to the radiation beam B is projected onto a target portion C at one time (i.e., a single static exposure). The substrate table WT is then shifted in the X and/or Y direction so that a different target portion C can be exposed. 2. In scan mode, the support structure (for example, mask table) MT and the substrate table WT are scanned synchronously while a pattern imparted to the radiation beam B is projected onto a target portion C (i.e., a single dynamic exposure). The velocity and direction of the substrate table WT relative to the support structure (for example, mask table) MT can be determined by the (de-)magnification and image reversal characteristics of the projection system PS. 3. In another mode, the support structure (for example, mask table) MT is kept substantially stationary holding a programmable patterning device, and the substrate table WT is moved or scanned while a pattern imparted to the radiation beam B is projected onto a target portion C. A pulsed radiation source SO can be employed and the programmable patterning device is updated as required after each movement of the substrate table WT or in between successive radiation pulses during a scan. This mode of operation can be readily applied to maskless lithography that utilizes a programmable patterning device, such as a programmable mirror array of a type as referred to herein.
Combinations and/or variations on the described modes of use or entirely different modes of use can also be employed.
Although specific reference can be made in this text to the use of lithographic apparatus in the manufacture of ICs, it should be understood that the lithographic apparatus described herein can have other applications, such as the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, flat-panel displays, liquid-crystal displays (LCDs), and thin-film magnetic heads. The skilled artisan will appreciate that, in the context of such alternative applications, any use of the terms “wafer” or “die” herein can be considered as synonymous with the more general terms “substrate” or “target portion,” respectively. The substrate referred to herein can be processed, before or after exposure, in for example a track (a tool that typically applies a layer of resist to a substrate and develops the exposed resist), a metrology tool, and/or an inspection tool. Where applicable, the disclosure herein can be applied to such and other substrate processing tools. Further, the substrate can be processed more than once, for example, in order to create a multi-layer IC, so that the term substrate used herein can also refer to a substrate that already contains multiple processed layers.
In a further embodiment, lithographic apparatus 100 includes an extreme ultraviolet (EUV) source, which is configured to generate a beam of EUV radiation for EUV lithography. In general, the EUV source is configured in a radiation system (see below), and a corresponding illumination system is configured to condition the EUV radiation beam of the EUV source.
In the embodiments described herein, the terms “lens” and “lens element,” where the context allows, can refer to any one or combination of various types of optical components, including refractive, reflective, magnetic, electromagnetic, and electrostatic optical components.
Further, the terms “radiation” and “beam” used herein encompass all types of electromagnetic radiation, including ultraviolet (UV) radiation (for example, having a wavelength λ of 365, 248, 193, 157 or 126 nm), extreme ultraviolet (EUV or soft X-ray) radiation (for example, having a wavelength in the range of 5-20 nm such as, for example, 13.5 nm), or hard X-ray working at less than 5 nm, as well as particle beams, such as ion beams or electron beams. Generally, radiation having wavelengths between about 780-3000 nm (or larger) is considered IR radiation. UV refers to radiation with wavelengths of approximately 100-400 nm. Within lithography, the term “UV” also applies to the wavelengths that can be produced by a mercury discharge lamp: G-line 436 nm; H-line 405 nm; and/or, I-line 365 nm. Vacuum UV, or VUV (i.e., UV absorbed by air), refers to radiation having a wavelength of approximately 100-200 nm. Deep UV (DUV) generally refers to radiation having wavelengths ranging from 126 nm to 428 nm, and in an embodiment, an excimer laser can generate DUV radiation used within a lithographic apparatus. It should be appreciated that radiation having a wavelength in the range of, for example, 5-20 nm relates to radiation with a certain wavelength band, of which at least part is in the range of 5-20 nm.
FIG. 2 is a schematic illustration of a patterning device transport system 200 , according to an embodiment of the invention. Patterning device transport system 200 includes a support transport device 230 and a holding system having a support device 250 , a holding device 280 , and a magnetostrictive actuator 260 . Transport device 230 moves support device 250 . Support device 250 supports a patterning device 270 . Magnetostrictive actuator 260 applies a force to patterning device 270 during an accelerating portion of a scanning motion profile. Holding device 280 holds patterning device 270 , such that during a constant velocity portion of a scanning motion profile there is no displacement of the patterning device 270 relative to support device 250 .
In one example, patterning device 270 (for example, a mask, a reticle, or a dynamic patterning device) is releasably held to support device 250 by holding device 280 (for example, a vacuum system). Support device 250 can be configured to move in both an x-direction and a y-direction. Transport device 230 can be coupled to support device 250 , such that transport device 230 provides sufficient force to accelerate support device 250 during an acceleration portion of a scanning motion profile.
In one example, transport device 230 may move support device 250 , and the releasably held patterning device 270 , at a high rate of speed and acceleration. High acceleration can generate a shearing force between patterning device 270 and support device 250 . The shearing force can cause slippage of patterning device 270 , relative to holding device 280 and support device 250 . To substantially eliminate the shearing force, a magnetostrictive actuator 260 may be releasably coupled to patterning device 270 . Magnetostrictive actuator 260 can provide a sufficient force directly on patterning device 270 to reduce the shearing force between patterning device 270 and support device 250 . Given the coupling of magnetostrictive actuator 260 to patterning device 270 , holding device 280 can provide a sufficient holding force, such that there is substantially no relative movement between patterning device 270 and support device 250 .
In one example, the holding device 280 includes a releasable vacuum clamp system to hold patterning device 270 in a relatively stationary manner during movement. In another example, holding device 280 can use other suitable methods to hold patterning device 270 , such as a high friction coating, as known to one of ordinary skill in the art. A high friction coating can also be used to increase the shear force capacity of a vacuum clamp.
FIG. 3 is a schematic illustration of a patterning device transport system 300 without anti-slip control according to an embodiment of the invention.
In this example, patterning device transport system 300 includes a long stroke device 310 , a support frame 320 , a support transport device 330 (for example, coils 330 A- 330 D and magnets 340 A- 340 D), a support device 350 , and a holding device 380 that releasably couples a patterning device 370 to the support device 350 .
In an example, support device 350 can be magnetically levitated relative to support frame 320 by vertically oriented Lorentz type actuators (not shown). There can be no physical contact between support frame 320 and support device 350 .
In one example, a patterning device 370 (for example, a mask, a reticle, or a dynamic patterning device) may be releasably held to support device 350 by holding device 380 . In one example, holding device 380 may comprise a pair of vacuum clamps 380 A and 380 B that hold patterning device 370 to support device 350 through friction enhanced by a vacuum force. In one example, support device 350 can move in both the x-direction and y-direction. In one example, coils 330 A- 330 D can provide a force in the y-direction to produce a motion of support device 350 . Magnets 340 A- 340 D electromagnetically couple coils 330 A- 330 D without physical contact. Pairs of respective items 330 - 340 comprise Lorentz type electromagnetic actuators as known in the art as pure force couplings.
In one example, long stroke device 310 moves support frame 320 in the x direction (via X-oriented Lorentz actuators not shown) at a relatively slow speed that does not generate any shearing forces between patterning device 370 and support device 350 .
In one example, transport device 330 moves support device 350 and releasably held patterning device 370 in the +y and −y directions accelerating at a relatively high rate to a substantial scanning speed. In one example, transport device 330 allows for high Y-forces to be exerted by support frame 320 to support device 350 . In one example, transport device 330 includes coils 330 A- 330 D and magnets 340 A- 330 D. In one example, the coils 330 A- 330 D are mounted to support frame 320 and magnets 340 A- 340 D are coupled to support device 350 .
For example, to move support device 350 with the releasably coupled patterning device 370 , in a −y direction (for example, left to right in FIG. 3 ), coils 330 A and 330 C are energized to produce a repelling force against magnets 340 A and 340 C. When coils 330 A and 330 C are energized, the repelling force against magnets 340 A and 340 C propels support device 350 in the −y direction. To assist movement of support device 350 in the −y direction, coils 330 B and 330 D are energized, such that they substantially simultaneously produce a pulling force to magnets 340 B and 340 D. Therefore, coils 330 A and 330 C and magnets 340 A and 340 C push support device 350 in the −y direction, while coils 330 B and 330 D and magnets 340 B and 340 D substantially simultaneously pull support device 350 in the −y direction.
Similarly, movement of the support device 350 and patterning device 370 in the +y direction is performed in the same manner, except the forces are reversed. Device coils 330 A and 330 C and magnets 340 A and 340 C, when energized, pull support device 350 in the +y direction, while coils 330 B and 330 D and magnets 340 B and 340 D substantially simultaneously push support device 350 in the +y direction.
It is to be appreciated that the embodiment shown in FIG. 3 relies on the friction created by holding device 380 (for example, vacuum clamps and/or friction coating) between patterning device 370 and support device 350 to prevent slippage of patterning device 370 during movement.
FIG. 4 is a schematic illustration of a patterning device transport system 400 with anti-slip control according to an embodiment of the invention.
In this example, patterning device transport system 400 includes a support frame 420 coupled to a long-stroke device (not shown), a support device 450 coupled to a support transport device (not shown), a holding device 480 that releasably couples a patterning device 470 to support device 450 , and a magnetostrictive actuator 460 .
In one example, patterning device transport system 400 works in a similar manner to patterning device transport system 300 , but with the addition of magnetostrictive actuator 460 . Movement in the x direction is accomplished as in FIG. 3 through the use of a long stroke device (not shown), which moves support frame 420 on which support device 450 is coupled. Movement in the y direction is accomplished as in FIG. 3 through the use of a coupled support transport device (not shown). In one example, to move in the −y direction, the support transport device, for example, electromagnetically coupled coils and magnets, are energized to move support device 450 in the −y direction, while movement of the support device 450 and patterning device 470 in the +y direction is done in the same manner, except that the forces are reversed.
In another example, magnetostrictive actuator 460 is used in patterning device transport system 400 to supplement the frictional force created by holding device 480 (for example, vacuum clamps or friction coating) with a normal push force applied directly to patterning device 470 at the edge opposite to the direction of acceleration to substantially reduce or eliminate patterning device slip. In one example, magnetostrictive actuator 460 can include a magnetic field source 462 , a push rod 463 , a biasing device 464 , and a clamping device 465 . Magnetostrictive actuator 460 can further include additional magnetic field sources, push rods, biasing devices, and clamping devices on either the same side or the opposite side of patterning device 470 , which operate in substantially the same manner.
In one example, push rod 463 comprises a magnetostrictive material that changes its shape or dimensions under a magnetic field. The push rod 463 can be electromagnetically coupled with magnetic field source 462 . When magnetic field source 462 creates a magnetic field, push rod 463 changes dimensions and releasably couples with patterning device 470 .
In one example, magnetic field source 462 is a coil, and push rod 463 passes through the coil. When the coil is energized, the resulting magnetic field increases the length of push rod 462 such that a distal end 466 of the push rod 463 contacts the patterning device 470 . The contact between distal end 466 of push rod 463 and patterning device 470 produces a force directly on patterning device 470 . The magnetostrictive material can be any suitable material that change dimensions under a magnetic field. The push rod's magnetostrictive material and dimensions, as well as the coil's turns per unit length of the push rod and current, can be modified or adjusted to achieve the desired change in length of the push rod 463 . Further, because the change in length of the push rod 463 caused by the magnetic field is substantially linear and repeatable, additional position and force sensors to control the push rod 463 in closed-loop operation are not necessary. Instead, the repeatable response of push rod 463 may be used during open-loop operation. Such sensors, however, may be used to calibrate the patterning device transport system 400 before manufacturing any ICs or other devices and/or structures.
In one example, the magnetostrictive material is Terfenol-D, and the push rod 463 is approximately 0.75 cm in diameter, and approximately 5 cm in length. In this example, the coil has approximately 500 turns over the length of the rod 463 and is driven by approximately a 1 A current. This example is provided merely to exemplify the invention, and the invention is not limited to these specific examples of rod material, rod dimensions, coil turns, and coil current.
In another example, the magnetostrictive actuator includes a biasing device 464 biases the push rod 463 towards the patterning device 470 . Although the biasing device 464 is illustrated as a spring in FIG. 4 , the biasing device 464 is not limited to springs. The biasing device 464 can be a spring, a pneumatic actuator, a bi-stable actuator, or any other suitable device for applying a biasing force to the push rod 463 . The biasing device 464 can apply a preload to set the initial gap 467 between the distal end 466 of the push rod 463 and the patterning device 470 as discussed below with reference to FIGS. 7 and 8A-8D . The biasing device 464 can also allow the push rod 463 to retract away from the patterning device 470 during patterning device exchanges. In another example, biasing device 464 can be configured also to retract push rod 463 away from patterning device 470 .
In one example, the magnetostrictive actuator 460 can also include a clamping device 465 . Clamping device 465 is configured to releasably couple a proximal portion 468 of push rod 463 to support device 450 . When coupled, clamping device 465 prevents the proximal portion 468 from moving relative to the patterning device 470 . Clamping device 465 can, for example, include a vacuum system or any other suitable device for releasably coupling a portion of the push rod 463 .
In one example, a common control signal controls the transport device coupled to the support device 450 and the magnetostrictive actuator 460 . For example, the current used to drive the transport device, for example, electromagnetically coupled coils and magnets, can be used to control the magnetic field source 462 . Thus, the transport device moves the support device 450 substantially simultaneously with energizing the coil of the magnetic field source 462 to create a magnetic field. Also substantially simultaneously, the magnetic field causes the length of the push rod 463 to increase and contact patterning device 470 . This operation produces a force on both the patterning device 470 to supplement the friction force created by holding device 480 . In another example, the current that drives the long-stroke device coupled to support frame 420 can be used to control the magnetic field source 462 . Accordingly, the coil of magnetic field source 462 is energized and the length of push rod 463 is increased simultaneously with moving support frame 420 with the long-stroke device. These configurations eliminate the need for additional control signal processing devices, for example, signal amplifiers, for the signal that controls magnetostrictive actuator 460 .
In another example, however, the signal that controls the magnetostrictive actuator 460 is separate from the signal that controls the transport device or long-stroke device. In this example, additional control signal processing devices, for example, a signal amplifier, may be necessary for the magnetostrictive actuator 460 .
FIG. 5 is a schematic illustration of a stage system 500 for a lithographic apparatus according to an embodiment of the invention. Stage system 500 includes stage control system 530 , a stage 550 which is movable, and a magnetostrictive actuator 560 .
In one example, a patterning device 570 is releasably held to stage 550 (for example, using a vacuum). Stage control system 530 is coupled to stage 550 . Stage control system 530 can provide sufficient force to allow movement of stage 550 . Stage control system 530 can move stage 550 , and the releasably held patterning device 570 , at a high rate of speed with a corresponding high rate of acceleration. Such acceleration can generate a shearing force between patterning device 570 and stage 550 , such that patterning device 570 can slip relative to stage 550 . To substantially eliminate the shearing force, a magnetostrictive actuator 560 is releasably coupled to patterning device 570 . Magnetostrictive actuator 560 can provide a force directly to patterning device 570 to reduce the shearing force between patterning device 570 and stage 550 . The force between patterning device 570 and stage 550 is such that, given the coupling of magnetostrictive actuator 560 to patterning device 570 , there is sufficient holding force such that there is substantially no relative movement between patterning device 570 and stage 550 .
In another embodiment stage 550 can use other methods to hold patterning device 570 , such as a friction coating or other methods as known to one of ordinary skill in the art.
FIG. 6 is an illustration of a flowchart depicting a method 600 for moving a patterning device according to an embodiment of the present invention. For example, method 600 may be performed using one or more of the above devices depicted in FIGS. 1A, 1B, and 2-5 . In this example, method 600 starts at step 602 , and proceeds to step 604 . In step 604 , a patterning device is supported with a support device. In step 606 , the patterning device is concurrently supported using a holding device, for example, a vacuum system. In step 608 , the support device is moved using a first moving device. In step 610 , a force is applied to the patterning device using a magnetostrictive actuator concurrently with moving the support device. The method then ends at step 612 .
FIG. 7 is an illustration of a flowchart depicting a method 700 for loading a patterning device on a patterning device transport system according to an embodiment of the present invention. The change in length of a magnetostrictive push rod under a magnetic field can be limited to tens of micrometers. Thus, the distal end of the push rod must be located in close proximity to the patterning device when not exposed to a magnetic field and in its non-extended state. Additionally, the push rod cannot be in constant contact with the patterning device during the scan interval because thermal expansion of the push rod can disturb the positioning of the patterning device. Thus, it is desirable to load a patterning device on a patterning device transport system according to method 700 to automatically create an initial gap between the distal end of the push rod and the patterning device.
In this example, method 700 starts at step 702 , and proceeds to step 704 . In step 704 , a patterning device is supported with a support device. In step 706 , a biasing device moves a magnetostrictive push rod against the patterning device on the support device. In step 708 , a magnetic field is created using a magnetic field source. In one example, the magnetic field is proportional to the desired no-field clearance or gap between the push rod and the patterning device. The magnetostrictive push rod, which is electromagnetically coupled with the magnetic field source, increases in length. Steps 706 and 708 are interchangeable and may be performed concurrently. In step 710 , a proximal portion of the magnetostrictive push rod is releasably coupled to the support device using a clamping device, for example a vacuum system. In step 712 , the magnetic field is removed, and the magnetostrictive push rod returns to its original length, creating a gap between the distal end of the push rod and the patterning device. The process ends at 714 .
FIGS. 8A-8D are schematic illustrations of a patterning device transport system 800 with anti-slip control at different steps of method 700 for loading a patterning device 870 on a patterning device transport system 800 including a support frame 820 . In each of these figures, a magnetorestrictive actuator 860 is biased by a biasing device 864 , pictured as a spring.
In FIG. 8A , while the coil of magnetic field source 862 is de-energized and not forcing magnetostrictive actuator 860 , the patterning device 870 is placed on support device 850 (step 704 ). Biasing device 866 moves magnetostrictive push rod 863 towards patterning device 870 such that the distal end 866 of push rod 863 contacts patterning device 870 (step 706 ). This contact creates a preload force against patterning device 870 . In FIG. 8B , the coil of magnetic field source 862 is energized to create a magnetic field (step 708 ). The length L of magnetostrictive push rod 863 , which is electromagnetically coupled to magnetic field source 862 , is increased.
In FIG. 8C , a proximal portion 868 is releasably coupled to the support device 850 using a clamping device 865 , for example, a vacuum system (step 710 ). When clamped, the proximal portion 868 is fixed relative to the patterning device 870 . In FIG. 8D , the coil of magnetic field source 862 is de-energized to remove the magnetic field. When the magnetic field is removed, the length L of magnetostrictive push rod 863 returns to its original length, as in step 704 . The decrease in length L creates a gap 867 between the distal end 866 of the push rod 863 and the patterning device 870 . In one example, gap 867 is approximately 2 micrometers.
In one example, method 800 is performed before for moving a patterning device 870 according to method 700 .
FIG. 9 is a schematic illustration of a stage system 900 with anti-slip control according to an embodiment of the invention. In this embodiment, the system includes a piezoelectric actuator 960 , instead of a magnetostrictive actuator as shown in prior embodiments. The system 900 can be configured in a similar fashion to the systems discussed above, and can be operated to reduce slippage of patterning device 970 during movement of a movable stage 950 controlled by a stage control system 930 in a similar manner as described above. For example, a voltage excitation can be used to create or manipulate an electric field, which changes the dimensions of a piezoelectric element of piezoelectric actuator 960 .
FIG. 10 is a schematic illustration of a partial side view of a patterning device transport system 1000 with anti-slip control according to an embodiment of the invention.
In this example, patterning device transport system 1000 includes a support frame 1020 coupled to a long-stroke device (not shown), a support device 1050 coupled to a support transport device (not shown), a holding device 1080 that releasably couples a patterning device 1070 to support device 1050 , and a piezoelectric actuator 1060 .
In one example, patterning device transport system 1000 works in a similar manner to the patterning device transport systems 400 , but with a piezoelectric actuator 1060 instead of a magnetostrictive actuator. Movement in the x direction is accomplished as in FIG. 4 through the use of a long stroke device (not shown), which moves support frame 1020 on which support device 1050 is coupled. Movement in the y direction is accomplished as in FIG. 4 through the use of a coupled support transport device (not shown). In one example, to move in the −y direction, the support transport device, for example, electromagnetically coupled coils and magnets, are energized to move support device 1050 in the −y direction, while movement of the support device 1050 and patterning device 1070 in the +y direction is done in the same manner, except that the forces are reversed.
In another example, piezoelectric actuator 1060 is used in patterning device transport system 1000 to supplement the frictional force created by holding device 1080 (for example, vacuum clamps or friction coating) with a normal push force applied directly to patterning device 1070 at the edge opposite to the direction of acceleration to substantially reduce or eliminate patterning device slippage.
In one example, piezoelectric actuator 1060 can include a piezoelectric element 1063 , a biasing device 1064 , and a clamping device 1065 configured to releasably couple a proximal portion 1068 of piezoelectric element 1063 to support device 1050 . Piezoelectric actuator 1060 can further include additional piezoelectric elements, biasing devices, and clamping devices on either the same side or the opposite side of patterning device 1070 , which operate in substantially the same manner.
In one example, piezoelectric element 1063 changes its dimensions under an electric field. The piezoelectric element 1063 can be electrically coupled to a voltage source via power terminals 1069 . When a voltage or charge is applied to piezoelectric element 1063 , the internal electric field of the piezoelectric element 1063 changes, which causes the piezoelectric element 1063 to change dimensions and releasably couple with patterning device 1070 . In one example, the resulting electric field increases the length of piezoelectric element 1062 such that a distal end of the piezoelectric element 1062 contacts the patterning device 1070 . The contact between the distal end of piezoelectric element 1062 and patterning device 1070 produces a force directly on patterning device 1070 . Piezoelectric actuator 1060 may be any suitable device that changes dimensions under an electric field, for example, piezoelectric stacks and tubes.
In another example, method 600 for moving a patterning device, as described above, may be performed using patterning device transport system 1000 . In this example, at step 610 , a force is applied to the patterning device using the piezoelectric actuator 1060 concurrently with moving the support device.
Further, method 700 for loading a patterning device, as described above, may be performed using patterning device transport system 1000 . In this example, at step 706 , a biasing device moves a piezoelectric element against the patterning device on the support device. In step 708 , an electric field is created by applying a voltage or charge to the piezoelectric element, which increases the length of the piezoelectric element. In step 710 , a proximal portion of the piezoelectric element is releasably coupled to the support device using a clamping device. In step 712 , the electric field is removed, and the piezoelectric element returns to its original length, creating a gap 1067 between the distal end of the piezoelectric element and the patterning device.
CONCLUSION
It is intended that the Detailed Description portion of this patent document, and not the Summary and Abstract sections, be used to interpret the claims. The Summary and Abstract portions may set forth one or more but not all exemplary embodiments of the present invention as contemplated by the inventor(s), and thus, are not intended to limit the present invention and the appended claims in any way.
The invention has been described above with the aid of functional building blocks illustrating the implementation of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description. Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed.
The foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can, by applying knowledge within the skill of the art, readily modify and/or adapt for various applications such specific embodiments, without undue experimentation, without departing from the general concept of the present invention. Therefore, such adaptations and modifications are intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by the skilled artisan in light of the teachings and guidance.
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. | In a lithographic apparatus, slippage of a patterning device is substantially eliminated during movement of a patterning device stage by providing a magnetostrictive actuator to apply an accelerating force to the patterning device to compensate for forces that would otherwise tend to cause slippage when the patterning device stage moves. | 6 |
FIELD OF THE INVENTION
[0001] The present invention discloses a new and economical process for preparation of ceftiofur acid starting from ceftiofur hydrohalide salt and treating it with a trimethylsilylating agent. The ceftiofur acid thus prepared was converted into its sodium salt by using some highly efficient sodium exchange reagent.
BACKGROUND OF INVENTION
[0002] Ceftiofur is the generic name given to compound of formula (I)
[0003] ceftiofur acid, its salts with alkali metal, alkaline earth metal and amines are reported for the first time in U.S. Pat. No. 4,464,367. All these derivatives of ceftiofur are known to have stability problems and are difficult to purify due to amorphous nature of the compounds.
[0004] An attempt to overcome these problems was made in U.S. Pat. No. 4,877,782 by preparing zinc complexes of ceftiofur which have better dispersibility in water and can be used in pharmacological preparations. U.S. Pat. No. 4,902,683 explains the isolation of ceftiofur in the form of crystalline hydrohalide salts which has better solubility and other physical properties compared to parent compounds. The hydrohalide salts as such cannot be used for parenteral administration, therefore it is necessary to convert a hydrohalide salt to sodium salt in order to use the drug as injectable.
[0005] Several methods are reported in patents for converting cephalosporanic acid to their corresponding alkali metal salt. This step is of special importance in case of injectable antibiotics. Surprisingly, very few methods are disclosed for preparing ceftiofur sodium starting from hydrohalide salt of ceftiofur. U.S. Pat. No. 4,937,330 describes the use of polyvinylpyridine for neutralization of hydrohalide salt to get free acid and then treating the few acid with sodium-2-ethylhexanoate. The use of sodium-2-ethyl hexanoate for this purpose is subject of several patents in field of cephalosporin antibiotics. The neutralization of hydrohalide salt using polyvinyl pyridine resin involves an extra filtration step in the process and the resin loses activity after certain batches and needs replacement which adds cost to the process.
[0006] In general, the process for liberation of ceftiofur free acid from hydrohalide salt using either resinous bases or non-resinous bases is associate with several problem. Keeping all these problems in mind, the Applicant discloses a simple, economical and commercially viable process for preparing ceftiofur sodium starting from ceftiofur hydrohalide salt which obviates the above mentioned limitations and does not use known neutralizing agents for this purpose. The process comprises of two steps:
[0007] (a) treatment of hydrohalide salt of ceftiofur with a trimethylsilylating agent which will neutralize the ceftiofur hydrohalide salt to give free ceftiofur acid; and
[0008] (b) the reaction of free ceftiofur acid with sodium exchanging agents for making sodium salt of ceftiofur acid
OBJECTS OF THE INVENTION
[0009] The primary object of the invention is a new process for preparing a ceftiofur sodium.
[0010] Another object of this invention is to neutralize the hydrohalide salt of ceftiofur to get free ceftiofur acid. This has been achieved by using N,O-bistrimethylsilyl acetamide, bis-trimethylsilylurea and Hexamethyl disilazane (HMDS). The applicant reports for the first time the use of these trimethylating agents for the purpose of neutralizing the hydrohalide salt of any cephem acid.
[0011] Yet another object of the invention relates to use of trimethylsilylating agent for the first time for the purpose of neutralizing the hydrohalide salt of any cephem acid.
[0012] Still another object of this invention is to make sodium salt thus prepared from ceftiofur acid using sodium lactate, sodium ethylacetoacetate, sodium-2-ethyl hexanoate and sodium acetate as sodium exchange reagent.
SUMMARY OF THE INVENTION
[0013] The present invention relates to a process for preparing sodium salt of cephalosporins from their corresponding hydrohalide salt, which is neutralized with trimethylsilylating agent for the first time.
DETAILED DESCRIPTION OF THE INVENTION
[0014] According to this invention treatment of hydrohalide salt of ceftiofur with a silylating agent in an aprotic solvent at a temperature ranging from 5 to 60° C. for 8-12 hrs gives free acid. The hydrohalide salt of ceftiofur employed in the present invention is well-known and commercially available. Hence, the present invention relates to a process for preparing a cephalosporin of formula (II)
[0015] the said process comprising;
[0016] (a) dissolving and neutralizing the hydrohalide salt of ceftiofur using a silylating agent in an aprotic organic solvent precipitation of a ceftiofur acid by quenching in water, and
[0017] (b) dissolving the ceftiofur acid of step (a) in a solvent and reacted with a sodium exchanging reagent dissolved in a suitable solvent and precipitating ceftiofur sodium with ethylacetate or acetone
[0018] Since the solubility of hydrohalide salt of ceftiofur is very poor in organic solvent and in aqueous phase, it is required to be solublize before neutralization takes place. Silylating agents such as N,O-bistrimethylsilyl acetamide, bis silyl-urea (BSU) and hexamethyl disilazane (HMDS) used herein plays a dual role in this reaction. First, it solublizes the hydrohalide salt of ceftiofur in an aprotic organic solvent and the by-product of this reaction neutralizes the hydrohalide salt, thus avoiding use of any other base. The silylating agent was used in mole ratio of 1.0 to 5.0 w.r.t hydrohalide salt but the most preferred ratio is about 3.0 moles w.r.t. hydrohalide salt of ceftiofur.
[0019] The solvents used in the process are selected from any of tetahydrofuran, dioxane, Dichloromethane, dimethylacetamide (DMAc), acetone, acetonitrile and mixtures thereof. Most suitable solvents were acetonitrile and DMAc. The reaction was carried out at temperature range of 25-60° C. but best results were obtained at 35-40° C. The reaction duration was about 8-12 hours.
[0020] The wet cake of ceftiofur acid thus obtained was converted to sodium salt using sodium exchanging agents like sodium lactate, sodium ethyl acetoacetate, sodium acetate and sodium 2-ethyl hexanoate. Ceftiofur acid was dissolved in suitable solvent and reacted with suitable sodium exchanging reagent, whereby the ceftiofur sodium product was precipitated by the addition of ethyl acetate or acetone.
[0021] The preferred process of this invention is to prepare sodium salt of ceftiofur starting from hydrohalide salt of ceftiofur acid.
[0022] The invention is illustrated with following examples but it should be understood that the invention is not intended to be limited to the specific embodiments herein.
EXAMPLE-1
7-[2-(2amino-1,3-thiazol-4yl)2-methoxyimino)acetamido]-3-[(fur-2-ylcarbonyl)thiomethyl]-3-cephem-4-carboxylic acid
[0023] A sample of ceftiofur hydrochloride salt (25.0 g) was suspended in acetonitrile (125 ml) around 28-30° C. N,O bis trimethylsilyl acetamide (27.5 gm) was added slowly. The temperature rose up to 45° C. The resultant solution was stirred for 8-9 hours at 28-30+ C. The solution was added to water (1000 ml) and stirred at 28-30° C. for 45-50 minutes. The solid material obtained was filtered and washed with water (2×50 ml). Product was dried under vacuum at 40-42° C. for 6-8 hours to give 20 g title compound.
EXAMPLE-2
7-[2-(2amino-1,3-thiazol-4-yl)2-methoxyimino)acetamido]-3-[(fur-2-ylcarbonyl)thiomethyl]-3-cephem-4-carboxylic acid
[0024] A sample of ceftiofur hydrochloride salt (25.0 g) was suspended in dimethylacetamide (105 ml) around 28-30° C. N,O bis trimethylsilyl acetamide (27.5 gm) was added. The temperature rose up to 45° C. The resultant solution was stirred for 8-9 hours at 28-30° C. The solution was added to water (1000 ml) and stirred at 28-30° C. for 45-50 minutes. The solid material obtained was filtered and washed with water (2×50 ml). Product was dried under vacuum at 40-42° C. for 6-8 hours to give (19 g) title compound.
EXAMPLE-3
7-[2-(2-amino-1,3-thiazol-4yl)2-methoxyimino)acetamido]-3-[(fur-2-ylcarbonyl)thiomethyl]-3-cephem-4-carboxylic acid
[0025] A sample of ceftiofur hydrochloride salt (25.0 g) was suspended in acetonitrile (125 ml) around 28-30° C. Bissilylurea (BSU) (35 gm) was added slowly to it. The temperature rose up to 45° C. The resultant solution was stirred for 8-9 hours at 28-30° C. The solution was added to water (1000 ml) and stirred at 28-30° C. for 45-50 minutes. The solid material obtained was filtered and washed with water (2×50 ml) Product was dried under vacuum at 40-42° C. for 6-8 hours to give (20 g) title compound.
EXAMPLE-4
7-[2-(2-amino-1,3-thiazol-4-yl)-2-methoxyimino)acetamido]-3-[(fur-2-ylcarbonyl)thiomethyl]-3cephem-4carboxylic acid
[0026] A sample of ceftiofur hydrochloride salt (25.0 g) was suspended in acetonitrile (125 ml) around 28-30° C. Hexamethyl disilazane (40 gm) was added slowly. The temperature rose up to 45° C. The resultant solution was stirred for 8-9 hours at 28-30° C. The solution was added to water (1000 ml) and stirred at 28-30° C. for 45-50 minutes. The solid material obtained was filtered and washed with water (2×50 ml). Product was dried under vacuum at 40-42° C. for 6-8 hours to give (20 g) title compound.
EXAMPLE-5
Sodium 7-[2-(2amino-1,3-thiazol-4-yl)2-methoxyimino)acetamido]-3-[(fur-2-ylcarbonyl)thiomethyl]-3-cephem-4-carboxylate
[0027] A sample of ceftiofur acid (5.0 gm, anhydrous basis) was suspended in methanol (25 ml) around 2-22° C., Triethylamine (1 g) was added dropwise in 20 minutes. The solution was treated with carbon and filtered off at 20-25° C. A solution of sodium lactate 60% w/w (1.7 g) in methanol (10 ml) at 28° C., was added drop wise and stirred. Acetone (165 ml) was added further for complete crystallization at 20-25° C. The crystalline product formed was filtered and washed with ethyl acetate (3×10 ml), product was dried under vacuum at 40-42° C. for 3-4 hours to get 3.8 gm of ceftiofur sodium (purity by HPLC 97.0%).
EXAMPLE 6
Sodium 7-[2-(2-amino-1,3thiazol-4-yl)2-methoxyimino)acetamido]-3-[(fur-2-ylcarbonyl)thiomethyl]-3-cephem-4-carboxylate
[0028] A sample of ceftiofur acid (5.0 g, anhydrous basis) was suspended in methanol (25 ml) around 20-22° C., Triethylamine (1 gm) was added dropwise in 20 minutes. The resultant solution was treated with carbon and filtered off at 20-25° C. A solution of ethyl acetoacetate sodium salt (1.5 g) in 10 ml of methanol was added dropwise to ceftiofur acid solution around 20-25° C. and stirred. Ethyl acetate (40 ml) was added further for complete crystallization at 20-28° C. The crystals were filtered and washed with ethyl acetate (3×10ml). Product was dried under vacuum at 40-42° C. for 3-4 hours to get 3.73 gm of ceftiofur sodium (purity by HPLC 98.0%)
EXAMPLE 7
[0029] Wet ceftiofur acid (2.5 gm on anhydrous basis, 4.7 mmol) was dissolved in tetrahydrofuran (45 ml) and the resultant clear solution was treated with sodium-2-ethyl hexanoate (1.2 gm, 72 mmol) at room temperature for 10 minutes. Acetone was added to precipitate out the ceftiofur sodium in crystalline form, which was separated by filtration. Solid was washed with acetone and dried it 40-42° C. to get 1.8 gm of ceftiofur sodium (purity by HPLC>97%).
EXAMPLE 8
[0030] Wet ceftiofur acid (2.5 gm on anhydrous basis, 4.7 mmol) was dissolved in tetrahydrofuran (45 ml) and the resultant clear solution was treated with sodiumethylacetoacetate (1.1 gm, 7.3 mmol) at room temperature for 10 minutes. Acetone was added to precipitate out the sodium ceftiofur in crystalline form, which was separated boy filtration. Solid was washed with acetone and dried at 40-42° C. to get 1.9 gm of ceftiofur sodium (purity by HPLC>98%).
EXAMPLE 9
[0031] A sample of ceftiofur acid (5.0 g, anhydrous basis) was suspended in methanol (25 ml) around 20-22° C. Triethylamine (1.0 gm) was added dropwise in 20 minutes. The resultant solution was treated with carbon and filtered off at 20-25° C. A solution of anhydrous sodium acetate (1.5 g) in 20 ml of methanol was added dropwise to ceftiofur acid solution around 20-25° C. Ethylacetate (40 ml) was added further for complete crystallization around 20-28° C. The crystals were filtered and washed with ethyl acetate (3×10 ml). Product was dried under vacuum at 40-42° C. for 3-4 hours to get 3.73 gm of ceftiofur sodium (purity by HPLC 97.0%). | The present invention relates to a process for preparing sodium salt of cephalosporins from their corresponding hydrohalide salt, which is neutralized with trimethylsilylating agent for the first time. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is the United States national phase of International Application No. PCT/IN2012/000580 filed Sep. 4, 2012, and claims priority to Indian Patent Application No. 345/KOL/2012 filed Mar. 28, 2012, the disclosures of which are hereby incorporated in their entirety by reference.
FIELD OF THE INVENTION
An improved way to produce low ash clean coal from high ash coal with total solvent recovery.
BACKGROUND OF THE INVENTION
As coal is a heterogeneous mixture of organic and inorganic constituents, the process of solvolysis of coal varies with its constituents, maturity, and structural characteristics. Since the mineral matter (non-combustible) in coals available in specific geographical location, is very finely disseminated in the organic mass, it is quite difficult to remove this non-combustible mineral matter by conventional physical coal washing techniques. Presence of high percentage of near gravity material in coal makes the scope of gravity process limited. It is known that chemical benefication originates from the limitations of physical beneficiation processes. Broadly, chemical beneficiation is possible by chemical leaching of mineral matter present in coal or, dissolving organic matter of coal in various organic solvents. This indicates that chemical treatment could be one of the solutions to overcome the limitations of physical benefication methods. Prior art teaches chemical beneficiation techniques that employ highly, corrosive chemicals (mostly acids and alkalis). Recovery or regeneration of these chemicals is very important to make this technology viable. A parallel approach towards lowering the ash-content could be recovery of the premium organic matter from coal by solvent refining. Most of the prior art disclose that chemical leaching is basically adapted to produce ultra clean coal or super clean coal with ash content less than 0.2% for various high tech end uses. However, such conventional solvent refining processes do not serve the objective of low ash coal requirement of steel industries because of mainly low recovery which makes the process uneconomic especially when such an ultra clean coal is not absolutely desired at the cost of lowering the yields. Additionally, the operating cost of said prior art process is high because of high cost of solvents and energy requirement in the process. In prior art process, the extraction is being done at boiling point of the solvent mixture making it difficult to recover the solvent from clean coal and reject. Thus, there is a need to propose a process of washing clean coal and reject to recover the remaining solvents. Also, there is a need to develop a process of extraction of coal at a temperature lower than the boiling point of the solvent mix.
By way of reference, the inventors observed that Indian patent application numbers 1292/KOL/06, 1088/KOL/07, 1336/KOL/2008, 950/KOL/09, 1194/KOL/09, 611/KOL/09, 1581/KOL/08 are herein incorporated.
OBJECTS OF THE INVENTION
It is therefore an object of this invention to propose a process to produce low ash clean coal from high ash coal.
Another object of this invention is to propose a process to produce low ash clean coal from high ash coal, in which coal is extracted at higher temperature than the boiling point of solvent.
A still another object of this invention is to propose a process to produce low ash clean coal from high ash coal, in which less amount of solvent is used.
Yet another object of this invention is to propose a process to produce low ash clean coal from high ash coal, in which a washing step to recover solvent from clean coal and reject is implemented.
A further object of this invention is to propose a process to produce low ash clean coal from high ash coal, in which >99% solvent is recovered.
SUMMARY OF THE INVENTION
According to the invention, coal, solvent (N-Methyl-2-Pyrrolidone, NMP) and co-solvent (Ethylenediamine, EDA) are mixed thoroughly to produce coal slurry. The coal slurry is extracted in a known manner which includes coal-solvent mixture. According to the inventive process, coal is extracted by using solvent and co-solvent in the reactor. The coal solvent mixture is separated in a separation unit to produce a coarser fraction and a finer fraction. The finer fraction is fed to an evaporator unit to allow 70 to 80% of solvent recovery. The hot concentrated coal-solvent mixture is then flushed in a precipitation tank to precipitate the coal. Where, water as an anti-solvent is being used. Water separates the solvent from coal and we get water-solvent mixture, which is fed to distillation unit to separate solvent and anti-solvent. And precipitated coal is separated in a filter. In this inventive process, coal, solvent and co-solvent are being taken in a predefined ratio. Coal to solvent ratio is varied from 1:4 to 1:25 (wt/vol, g/mL, coal to solvent ratios are wt/vol and solvent: co-solvent ratios are vol/vol wherever mentioned). Coal to co-solvent ratio is varied from 1:1 to 10:1 and co-solvent to solvent ratio is varied from 1:1 to 1:50 (g/mL). Both clean coal and reject is being washed in a sequence shown in FIG. 1 . Following important equipments were there in the system, such as thermic fluid heater, reactor, heat exchanger, thermic fluid pump, inert gas (N 2 ) cylinder, feed tank for evaporator, double effect evaporator, feed pump, transfer pump, discharge pump, heat exchanger, condenser, cooling tower, cooling pump, concentrate tank, condensate tank, distillation feed tank, feed pump, distillation column, condenser, condenser tank, reflux pump, reboiler, reboiler pump, discharge pump, and bottom product tank. Some other equipments or vessels such as water storage tank, diesel storage tank, thermic fluid storage tank, expansion tank and centrifuge filter were also installed for this process.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
FIG. 1 shows a system for washing clean coal and rejects.
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1 , the system consists of a plurality of units, each unit comprising a precipitation tank, and a wash tank with stirrer system. Coal (reject or clean coal) and washed liquid is obtained from each unit. The coal and reject goes to next wash tank and washed liquid goes to previous wash tank.
Coal and solvent in predetermined ratio are loaded into a reactor. Nitrogen gas is supplied through N 2 cylinder for maintaining inert environment. Diesel is supplied to a burner from a diesel storage tank. Thermic fluid is supplied into the system from a thermic fluid storage tank. The thermic fluid is heated in a thermic fluid heater. On heating, the thermic fluid's volume increases, and accordingly, an expansion tank is used to store the extra thermic fluid. Hot thermic fluid is pumped by a thermic fluid pump to heat the reactor. During extraction, a sample is withdrawn from a sample port. On completion of the extraction, the burner is switched off. To cool down the thermic fluid heater, the thermic fluid is passed through a heat exchanger. Water is pumped in the heat exchanger through a water pump from a water storage tank. A reflux condenser maintains pressure and temperature at the reactor at a desired level.
Coal and solvents are loaded into the reactor in a predetermined ratio. Coal to total solvent ratio is varied from 1:4 to 1:25 (wt/vol, g/mL, coal to solvent ratios are wt/vol and solvent: co-solvent ratios are vol/vol wherever mentioned). Co-solvent to solvent ratio is varied from 1:50 to 1:1. Nitrogen gas is purged into the system for maintaining an inert environment. Thermic fluid is pumped into the system from the thermic fluid storage tank. Thermic fluid is heated in the thermic fluid heater by the diesel fired burner. The reactor is heated by hot thermic fluid. Reactor pressure is varied from 1 to 4 kg/cm 2 . Reactor temperature is varied from 100° C. to 240° C. Extraction is done for 15 minutes to 4 h in the reactor.
Sample is withdrawn from the reactor through the sample port in predetermined time intervals. This sample is filtered through a mesh. Filtration separates the refluxed mix in two parts (i) reject and (ii) filtrate (extracted material with solvents). Reject is washed thoroughly with an anti-solvent (water) for the removal of the solvents from the reject. After drying and weighing, these rejects are subjected to ash analysis. The filtrate is actually the extract containing very low ash coal. For precipitation an anti solvent (water) is taken in a vessel. Concentrated extract is then added in to the water. As these solvents are soluble in water, the solvents move to water phase. It resulted in precipitation of solid coal particles. The precipitated coal is then separated from the solvent-water solution through filtration. This step is carried out in a conical flask-funnel type arrangement with standard mesh. The reject of this filtration is the low ash clean coal; filtrate consists of water and the solvents. After drying and weighing, the clean coals are subjected to chemical and petro graphical analysis.
At a plant level, the recovery system comprises an evaporator feed tank, an evaporator feed pump, a first evaporator, a vapour collector, a second evaporator, a transfer pump, a discharge pump, a heat Exchanger, a concentrate product tank, a condenser, a condensate tank, a cooling tower, a cooling pump, a feed tank for distillation column, a feed pump for distillation, a distillation column, a condenser, a condensate tank, a distillate pump, a reboiler, a reboiler pump, a bottom product tank.
Reacted material in the reactor is taken out and filtered through a centrifuge filter. Filtration separates the refluxed mix in two parts (i) reject and (ii) filtrate (extracted material with solvents). Reject is washed thoroughly with an anti-solvent (water) for the removal of the solvents from the reject (as shown in FIG. 1 ). After drying and weighing, these rejects are subjected to ash analysis. The filtrate is actually the extract containing very low ash coal. Filtrate (extracted material along with solvents) are taken into the evaporator feed tank. Feed material is fed to both the evaporators through the feed pump. Heating is started in the second tank through hot thermic fluid. As the material is heated in the second evaporator, vapour is generated. Vapour passes through the vapour collector tank and then goes to the first evaporator to pre heat the input material. Vapour generated in the first evaporator passes through the vapour collector and finally passes through the condenser. The condensate is collected in the condensate tank. The discharge pump is activated to allow discharge of the concentrated material through the discharge pump to the concentrate product tank with or without cooling. Concentrated product is continuously taken out into the concentrate product tank. This cycle is allowed to continue till a substantially concentrate material is obtained. About 80-85% solvent is evaporated in this evaporator.
The concentrated material is precipitated in water in the mixing tank. As these solvents are soluble in water, solvents move to water phase. It resulted in precipitation of solid coal particles. Thus, precipitated coal is then separated from solvent-water solution through the centrifuge filter. Clean coal is further washed (as shown in FIG. 1 ) till all the solvent is removed from coal. Water-solvent mixture is stored in a storage tank, which is separated in a distillation column.
Water-solvent mixture is fed to the distillation feed tank. The feed pump is started to feed the material into the distillation column. The reboiler pump is started to allow flow of thermic fluid in the reboiler to heat the material. This water-solvent mixture is heated up by circulating it through the reboiler. After some time this whole material is heated up and water vapour is generated. This vapour comes out from top vapour line. The reflux (distillate) pump is started to recycle the distillate into the distillation column. Vapour passes through the condenser and condensed water goes to the distillate tank. This distillate is fed to the distillation column till an equilibrium is achieved (based on reflux ratio). The top product (distillate) can be taken out from the distillate line. This continuous cycle of feeding material to the distillation column, heating it through the reboiler and recycling it through the condenser continuous till the feed material is distillated.
The bottom product discharge pump is operated to collect the bottom product into the bottom product tank. Water and solvent is separated and stored in different tanks, which can be used again in the process.
Clean coal and reject coal is washed as shown in the FIG. 1 . Basically, it is a countercurrent washing where fresh water is used, to wash last batch of clean coal and reject (least contaminated with solvents) in the wash tank 8 and 9 . Coal extract along with wash liquid WO 1 and WE 1 is fed to precipitation tank (PPT TANK 1 ). Coal is precipitated and clean coal (C 0 ) and wash liquid (WO 0 ) are obtained. The clean coal is fed to next wash tank 2 , and wash liquid WO 0 to distillation column, where water and solvent is separated. In the wash tank 2 clean coal C 0 and wash liquid WO 2 is fed, which gives clean coal C 1 and wash liquid WO 1 . Clean coal C 1 and wash liquid WO 3 is fed to wash tank 4 , which gives clean coal C 2 and wash liquid WO 2 . Clean coal C 2 and wash liquid WO 4 is fed to wash tank 6 , which gives clean coal C 3 and wash liquid WO 3 . Clean coal C 3 and fresh water is fed to wash tank 8 , which gives clean coal C 4 and wash liquid WO 4 . Reject along with WE 2 is fed to wash tank 3 , which gives reject R 1 and wash liquid WE 1 . Reject R 1 and wash liquid WE 1 . Reject R 1 along with WE 3 is fed to wash tank 5 , which gives reject R 2 and wash liquid WE 2 . Reject R 2 along with WE 4 is being fed to wash tank 7 , which gives reject R 3 and wash liquid WE 3 . Reject R 3 along fresh water is fed to wash tank 9 , which gives reject R 4 and wash liquid WE 4 . Fresh water is given only at one stage and the same water is used in all other steps in washing. By this strategy, water consumption is less compared to conventional washing.
Many trials were conducted by varying different process parameters such as temperature (100° C. to 240° C.), coal to solvent ratio (1:4 to 1:25), size fraction (−1 mm, to −0.1 mm), different coal origin, filter pore size, co-solvent to solvent ratio. The typical feed coal samples were run-of-mines (ROM) coal and flotation clean coal having about 25-35% and 12-15% ash respectively. The feed particle size varied from −1 mm to −0.1 mm and extraction was done at different temperature.
Some of the typical results are shown here, for example, clean coal yield varied from 45% to 60%. Clean coal ash was about 4%. It is possible to produce less than 8% ash clean coal with 60% yield and about 80% combustible recovery with this process. With the help of fine filtration even less than 1% ash clean coal could be possible. With some typical coal, 70% of clean coal yield could be achieved. | A process to produce low ash clean coal from high ash coal with substantially complete solvent recovery, the process including: forming a slurry of coal fines in a N-Methyl-2-pyrrolidone (NMP) and Ethylenediamine (EDA) solution; maintaining said slurry in a reactor at a temperature range of 100° C. to 240° C. and a pressure range of 1 to 4 gauge (kg/cm2) for a period of about 15 minutes to 4 hours; separating the produced sample withdrawn from the reactor, one part being a filtrate and the other a reject; feeding the filtrate into an evaporator to recover 80-85% solvent; precipitating the concentrated filtrate material in an anti-solvent tank to separate coal from solvent; separating the coal by filtration, said separated coal having a reduced ash content; feeding the anti-solvent and solvent mixture into a distillation column to separate remaining solvent from the anti-solvent for reuse in the process. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to water heaters, hot water boilers and air furnaces for residential and commercial use, hereafter referred as residential heaters, which utilize a heat of fuel combustion as a heat source.
The present invention also relates to a method of transmitting a fuel heat energy to a medium.
Residential heaters have found broad implementation both in North America and around the world. That is why they became one of the important issues to cope with greenhouse effect and environmental pollution. For instance, in the United States the adverse impact of the space heating systems is of the same order as the yearly impact generated by highway traffic in conjunction with the most hazardous pollutant formation, such as nitrogen oxides. On the other hand their contribution to the greenhouse effect occurs due to relatively low annual fuel utilization efficiency. The later Department of Energy standard as of 1992 require the annual fuel utilization efficiency to be not less than 80% for hot water and steam residential boilers, and 78% for air heaters and furnaces with output rated up to 300,000 Btu/Hr. Nowadays the best residential boilers available on the market have the annual fuel utilization efficiency up to 84.5% for non-condensing and 91% for condensing designs.
The residential heaters utilize the heat of fuel combustion products to heat up an actuating medium such as water or air in order to bring the necessary amount of heat into a residential heating system. The heat from the combustion product is transferred to an actuating medium through the solid heat exchange surface by means of a free or forced convection. The free heat transfer mode is less efficient especially for gaseous media, i.e. it has an intrinsically low rate of heat transfer coefficient per unit of hour, heat exchange surface, and per a degree of temperature difference. This restricts the efficiency of the residential fuel heaters and, in turn, requires relatively a big and expensive heat exchanger surface to satisfy the necessary heat output. The forced convection which commonly is achieved by means of induced draft, does not make a difference for such restriction and yet leads to more expensive and complicated design.
Another narrow spot of the existing residential heater designs is an unstable and incomplete combustion and a safe operation for those heaters which have the output rated less than 60,000 Btu/Hr. In turn, it mandates the implementation of induced draft which unavoidably involves the above mentioned disadvantages. Besides, with the present design concept the heat transfer occurs at a relatively high average temperature and it causes the thermal nitrogen oxide formation which rising exponentially with the temperature.
Among other related disadvantages of the existing residential heaters involve insufficient safety of their operation. An additional precaution should be exercised to prevent a water hammering in case of water used as the actuating medium. Since water has the boiling temperature much lower than combustion products, a high chance of its sublimation exists. In connection with this, the control is provided with a pressure relief valve to reduce sudden pressure fluctuations of the actuating medium. This again contributes to complications of the control equipment and increase of the overall cost.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a device which avoids the disadvantages of the prior art.
More particularly, it is an object of the present invention to provide a device which allows more efficient utilization of fuel high heat value along with a concurrent enhancement of the heat transfer from the combustion products to the actuating medium, either water or air, and provides considerable decrease of the required heat exchange surface, with implementation in the combustion process of a forced draft and suppression of nitrogen oxides formation.
In keeping with these objects and with others which will become apparent hereinafter, one feature of the present invention resides, briefly stated, in a residential boiler burner which has an intermediate water circuit including a water pump and an ejector. The driving end of the ejector is connected with a pump outlet while a suction line is connected to a combustion zone. Thus, the water circulating through the intermediate circuit creates a negative pressure at the combustion zone outlet which allows its reliable supply with the combustion air and flue gas discharge. After burning of the fuel, all combustion products are sucked into the ejector to undergo a direct mixing with the water in the intermediate circuit. Due to the mixing, the circulating water accumulates an overwhelming part of the fuel high heat value, i.e., also including the heat of water vapors generated by combustion process. The flue gas temperature leaving the water circuit shall never exceed the water boiling temperature which is considerably lower than the temperature of the gas leaving the conventional residential boiler. From the thermodynamic standpoint, a corresponding heat efficiency increase has been proven.
In accordance with the present invention, also a method of transmitting a fuel heat energy to water or air is provided with the corresponding new features.
The intermediate water serves as a transmitting medium, to deliver a necessary heat to the actuating medium, either water or air, through the heat exchanger. The suction line of the intermediate circulating pump is connected with the heat exchanger to allow more efficient heat utilization of the circulating water by means of the forced convection heat transfer mode, and therefore leads to at least two times exchange surface reduction. The heat exchanger is also provided with an exhaust pipe. Due to the presence of the ejector, an excessive pressure on the discharge end of the intermediate circuit is built within the heat exchanger casing to force flue gases to leave through the exhaust pipe. The exhaust pipe along with the part of the return line of the actuating medium (or down comer) makes up an annulus which serves as a heat exchanger surface, to condense some water vapor from the exhaust products, since an equilibrium moisture is always present above the water surface at any temperature. This is also an additional means to increase useful output by recovering the useful heat from the flue gases.
The amount of the intermediate circulating water supply is consistent with the current heat output, while maintaining a temperature slightly lower than the boiling temperature to allow a complete condensation of the water vapor in the combustion products as well as to minimize their solubility. It is known that the gas solubility in water decreases as the temperature rises, and approaches zero at the boiling temperature. As said amount strictly depends on the necessary output, one motor may be used to drive both the intermediate circulating water and the actuating medium. To avoid complications in conjunction with the use of additional valves to control the additional circuit, a variable speed motor may be optionally used to drive the two media without any control valves.
The ejector allows to control air supply, which makes possible to implement any advance combustion technique such as air stagening without involving any other expensive equipment, and in turn to gain considerable emission reduction as the above mentioned nitrogen oxides. Besides, since the flame is quenched in the ejector, this leads to dramatic reduction of the average process temperature when compared with conventional residential heaters. As estimated overall effect of the thermal and prompt nitrogen oxides suppression is at least 60%. In particular, this is true for thermal, prompt and fuel nitrogen oxides.
Since the intermediate circuit is connected directly to atmosphere in the actuating medium, in particular water, has always higher temperature by operational requirements, there is no way the water can reach boiling temperature at any heater load, and in turn no hammering effect will ever take place. This fact both simplifies the control system and enhances the heater reliability with respect to safety operation.
The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view schematically showing a method of transmitting fuel heat energy to a heating system, such as water or air actuating medium, through a closed intermediate water circuit in accordance with the present invention; and
FIG. 2 is a view schematically showing a method of transmitting fuel heat energy to a heating system, such as a water actuating medium only, through an open intermediate water circuit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A heating system in accordance with one embodiment of the present invention is shown in FIG. 1. Here fuel heat energy is transmitted to water or air heating system through an intermediate water circuit.
Fuel from a standard fuel train is supplied to a combustion chamber 1. The major part of atmospheric air required for complete combustion is sucked into the chamber 1 due to an induced draft created by a pressurized water passing through an ejector 2. The water pressure is provided by a pump 3. In a diffuser of the ejector, the water undergoes a direct mixing with flue gases sucked from the chamber 1 and accumulates an overwhelming part of heat energy of the flue gases, including heat of moisture due to combustion which they contain. The hot water maintained close to the boiling temperature then expands in an expansion vessel 4 where the flue gases are evacuated through a vent line 5 connected to a condenser 6. A further cooling of the flue gases takes place in the condenser 6 due to heat exchange with the cold actuating medium (water/air) which is returning from the heating system. This eliminates an equilibrium moisture from the flue gases by condensing and increases heat utilization efficiency. The flue gases finally discharge through a stack 7 due to an excessive pressure sustained by the ejector 2. The condensate from the condenser 6 can be either disposed into sewage line or returned to the expansion vessel.
The water from the expansion vessel 4 is supplied under pressure to a heat exchanger 8 where its heat is transferred to the actuating medium preheated in the condenser 6, and is driven by an actuator 9, formed either as a water pump or an air fan. Since the both media are force-driven, a high efficiency forced convection heat transfer mode takes place, and thereby a corresponding reduction of heat exchange surfaces is provided.
The water pump 3, the ejector 2 along with the expansion vessel 4, and a strainer 12 (optional), and one of the passes of the heat exchanger 8 together form an intermediate water circuit. A make up water inlet 10 and a drain water discharge 11 are provided to accommodate any level fluctuations in the intermediate water circuit due to water vapor from condensation of the flue gases or due to a partial water disposal.
It is clear that the output of the heating system determines the intermediate circuit output and they are also directly proportional. As a result, the pump 3 and the actuator 9 may be driven by one motor 13, so that the design of the heating system is simplified. On the other hand, it is possible to use separate motor-driven actuators.
A thermostat 14 controls an interior temperature. When the thermostat 14 calls for a rise in the interior temperature, the pump 13 is actuated and an air damper 15 opens completely to allow blowing down of any residue in the combustion chamber 1. When the pressure (draft) in the combustion chamber reaches a desired level, a pressure switch 16 opens a fuel shut-off valve. Thus, the heater transfers an invaluable heat output to the actuating medium until the required interior temperature is reached. When the required interior temperature has been reached, the thermostat also stops the heater in a reverse order. A variable restriction orifice 18 serves for adjusting an appropriate fuel combustion during the start up, to accommodate any deviations of specific conditions from the design conditions.
A heating system in accordance with a second embodiment is shown in FIG. 2. It is provided for transmitting fuel heat energy only to a water heating system. In this embodiment there is no heat transfer surface which leads to a significant reduction of both manufacturing and operation expenses. Also, here there is no restriction related to the heat transfer, which in turn results in higher heat performance efficiency. Also, the hazardous emissions are reduced in this construction.
The construction of the system shown in FIG. 2 substantially corresponds to the construction of the system shown in FIG. 1, and similar parts are identified with same reference numerals.
The heated water from the intermediate circuit is stored in a tank 8' and then mixed with the actuating water in another ejector 19'. To prevent the flue gases carry over into the actuating medium the hot intermediate water temperature is maintained at the boiling point in the expansion vessel 4, which can be combined in this case with the tank 8', to sustain a complete degassing of the water. In turn, it helps to avoid any voids within the heat transfer surfaces (baseboards) filled with flue gases in the heating system.
In order to apply the inventive heating system to a residential heater, the control system can include a temperature switch 20 connected to a shut off valve 21. The valve opens when the boiling temperature is reached, while the thermostat 14 calls for the interior temperature increase. If this request is not satisfied, but the temperature in the intermediate circuit has dropped lower than a preset temperature (slightly less than the boiling point), the shut off valve 21 closes to allow the water temperature in the intermediate circuit to reach the preset temperature.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions and methods differing from the types described above.
While the invention has been illustrated and described as embodied in a residential boiler/furnace with the intermediate water circuit, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.
What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims. | For transmitting a fuel heat energy to water or air the heating system performs the steps of producing fuel combustion products in a combustion chamber, sucking the fuel combustion products from the combustion chamber into an ejector and mixing the combustion products in the ejector with an intermediate water to provide an absorption of a combustion heat of the combustion products so as to heat the intermediate water, and supplying the heated water into a means in which the heated water transfers a heat accumulated in the heated water to a cold water from the heating system. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. Ser. No. 12/224,868, filed on Sep. 8, 2008, which claims priority to International Application PCT/EP2007/002021, filed on Mar. 8, 2007, which claims priority to German Application No. 10 2006 010 775.6, filed on Mar. 8, 2006, all of which are incorporated by reference herein.
BACKGROUND AND SUMMARY
[0002] The present invention relates to a method for weaving a webbing comprising a right-hand weft thread (SFR) and a left-hand weft thread (SFL), it also relating to a narrow fabric needle loom.
[0003] Known from DE 27 19 382 C3 (Berger) is weaving a single-ply seat belt webbing having tubular selvedges on a narrow fabric needle loom by a sole weft needle. One of two single-ply woven edge portions is pulled up to the selvedge of the middle portion to form the one tubular selvedge by pulling the weft thread.
[0004] Known from CH 648 069 A5 (Berger) is a webbing particularly for automotive seat belts made on a narrow fabric needle loom. The webbing features a relatively stiff middle portion and soft edge portions formed into tubular selvedges. To speed up production two weft needles are provided working simultaneously in parallel, the one picking a soft weft thread in the middle portion and the two edge portions, the other picking a stiffer weft thread in just the middle portion and picking only the two outermost warp threads of the two edge portions. Two weft needles pick simultaneously two different weft materials into partly different shed openings. The two flat edge portions are drawn into tubular selvedges by the one weft thread picked only via the middle portion. The middle portion is reinforced to achieve a higher performance. The aim was to double the output by using two weft needles as compared to single needle systems. However, the larger mass and the needed larger and faster movements of the auxiliary pickers resulting from the two weft needles only made it possible to achieve much less than twice the output.
[0005] Known from DE 33 45 508 C2 (leperband) is a webbing (safety belt) woven single-ply, likewise making use of two weft needles simultaneously to pick two different weft yarns. A monofil weft thread merely serves to reinforce the middle portion and must not be used to pull over the flat edge portions. By current standards these known webbings and methods of their production are too costly and have since ceased to satisfy the increasing demands of the automotive industry. What has particularly increased are the demands on webbing having comfortable soft edge portions whilst the inner portion is required to feature maximized transverse stiffness. On top of this, these known devices for producing webbing are very complicated and difficult to master in operation.
[0006] It is thus the object of the present invention to propose a webbing, a method and a narrow fabric needle loom of the aforementioned kind which now avoids or at least greatly minimizes the drawbacks of prior art. This object is achieved by a method as set forth in claim 1 , namely a method for weaving a webbing comprising a right-hand weft thread and a left-hand weft thread, characterized in that the two weft threads are picked into the same shed from both sides of the seat belt webbing, are wound around weft holdbacks in weft reversal loops, are substantially retained by the weft holdbacks until beat by the reed against the fell, it not being until then that a shed change is made. This technique in accordance with the invention results in two weft threads each coming simultaneously from the right-hand and left-hand weft picking side being picked practically symmetrically transversely over the webbing where they are each held back at the opposite side by a separate weft holdback provided there, after which the weft needles are retracted to their side thereby entraining the weft thread and holding it taut until the reed has beaten up the freshly picked weft threads to the already woven webbing material, the weft threads being held back up to this point in time by the weft holdbacks being set by the advanced shed change.
[0007] In this arrangement the webbing is advantageously produced without any need of tucking or crotchet, tongue or pusher needles whatsoever and also without any meshing or crotcheting of the weft thread being needed. These weaving devices as standard on more complicated means of prior art can now all be eliminated by application of the method in accordance with the invention. Merely weft holdbacks in contact with the usual control of catch needle holders are still needed.
[0008] An advantageous further embodiment of the method in accordance with the invention for weaving a seat belt webbing comprising an inner portion, a preferably soft right-hand edge portion and a preferably soft left-hand edge portion, is characterized by a continuous repeat of a first step sequence;
ar) picking the right-hand weft thread from the right-hand side of the webbing into the right-hand edge portion and into the inner portion by means of a right-hand weft needle, al) picking the left-hand weft thread from the left-hand side of the seat belt webbing into the left-hand edge portion and into the inner portion by means of a left-hand weft needle simultaneously to step ar), br) retaining the right-hand weft thread in the transition portion from the inner portion to the left-hand edge portion by means of a left-hand weft holdback, bl) retaining the left-hand weft thread in the transition portion from the inner portion to the right-hand edge portion by means of a right-hand weft holdback simultaneously to step br), cr) tucking the right-hand weft thread with the left-hand weft holdback and returning the left-hand weft holdback to the fell, cl) tucking the left-hand weft thread with the right-hand weft holdback and returning the right-hand weft holdback to the fell simultaneously to step cr), dr) returning the right-hand weft needle to the right-hand side of the seat belt webbing, dl) returning the left-hand weft needle to the left-hand side of the seat belt webbing simultaneously to step cr), e) stripping off the weft loops formed in the previous step from the two weft holdbacks by the reed to the fell and forwarding the two weft holdbacks away from the fell, f) beating the two weft threads by a reed.
The method is advantageously characterized in that two weft needles guiding the weft threads each coming from the right and left weft picking side respectively pick the weft threads simultaneously and practically symmetrically transversely over the webbing, each of which is held back on the opposite side in the transition between the inner portion and edge portion by the weft holdback element located there in each case, after which the weft needles are returned to their side entraining and tensioning the weft threads tensioned until the reed beats up the newly inserted weft threads to the already woven webbing material. Up until this point in time the weft threads held back by the weft holdbacks are beat up and set by the following shed change.
[0019] In application of the method in accordance with the invention as it reads from claim 2 both weft threads are arranged in the inner portion, and only one in each case being in the edge portion belonging to its weft thread picking side. This results in the advantage that each edge portion is occupied only with one weft thread and is thus softer, whilst the two weft threads in the inner portion endow it with a higher transverse stiffness due to twice the proportion of material as compared to the edge portions.
[0020] Another advantageous further embodiment of the method for weaving a seat belt webbing whose right and left-hand weft threads are hybrid threads is characterized by the following step implemented after weaving: thermosetting the seat belt webbing. Used as weft threads in this arrangement are hybrid threads as are converted after weaving by said thermosetting into monofil-type structures in endowing the seat belt webbing in accordance with the invention with additional monofil qualities adequately for transverse stiffness without making use of actual monofil threads. Hybrid threads are threads made of materials having different melting temperatures as are known from prior art. The advantage in this is that after weaving such hybrid threads as weft threads, as claimed herein, the hybrid threads can be solidified into a monofil condition by subjecting them to thermosetting after weaving, resulting in the components of the hybrid threads having a low melting point to melt embedding the components having a higher melting point into monofil type structures featuring enhanced flexibility, transverse stiffness and as termed with seat belt webbing, rebound transversely to the webbing.
[0021] A further advantageous aspect of the method in accordance with the invention is the use an additional left-hand weft needle for picking a monofil weft needle supplied in the transition between the left-hand edge portion and the inner portion, the monofil weft needle being held secure on both sides in addition to the just mentioned weft threads likewise by the weft holdbacks resulting in the monofil weft threads being woven only in the inner portion. This is characterized by the following further steps:
az) picking a monofil weft thread fed preferably in the transition portion from the inner portion to the left-hand edge portion from left to right up to the transition portion from the inner portion to the right-hand edge portion by means of a supplementary weft needle simultaneously to step ar) bz) retaining the monofil weft thread in the transition portion from the inner portion to the right-hand edge portion by means of the right-hand weft holdback simultaneously to step cr), cz) tucking the monofil weft thread with the right-hand weft holdback and returning the right-hand weft holdback up to just before the fell simultaneously to the step cr) dz) returning the supplementary weft needle simultaneously to step dr).
Catching, releasing and beating the monofil weft thread is done analogous to the actions as already described relating to the weft threads as described above, for which, as explained further on in the description, an additional weft needle is employed. The supplementary monofil weft thread additionally incorporated in the inner portion in accordance with the invention results in the advantage that the seat belt webbing now features enhanced transverse stiffness in the inner portion whilst the edge portions remain soft as wanted.
[0026] A further advantageous embodiment of the method in accordance with the invention for weaving a webbing is characterized by the following second sequence in the steps optionally alternated with the first sequence of steps as it reads from claim 2 for optionally forming picots at the selvedges of the webbing:
apr) picking the right-hand weft thread from the right-hand side of the webbing over the full webbing width beyond the left-hand webbing side by means of a right-hand weft needle), apl) picking the left-hand weft thread from the left-hand side of the webbing over the full webbing width beyond the right-hand webbing side by means of a left-hand weft needle, simultaneously to step apr), bpr) retaining the right-hand weft thread outside of the webbing adjoining the left-hand edge portion by means of a second left-hand weft holdback in forming weft loops, bpl) retaining the left-hand weft thread outside of the webbing adjoining the right-hand edge portion by means of a second right-hand weft holdback in forming weft loops simultaneously to step bpr), dr) returning the right-hand weft needle to the right-hand side of the seat belt webbing, dl) returning the left-hand weft needle to the left-hand side of the seat belt webbing simultaneously to step dr), ep) stripping off the weft loops formed in the steps bpr) and bpl) from the two weft holdbacks, f) beating the two weft threads by a reed.
This now makes it possible to produce webbing with weft loops or so-called picots optionally included to protrude beyond the selvedge which is particularly favorable in the production of ribbons and braids, mainly for ready-to wear garments. Involved in this is also a further advantageous embodiment of the method in accordance with the invention which is characterized by elastic warp threads being made use of.
[0035] In another advantageous further embodiment of the method in accordance with the invention multifil threads are employed as weft threads to guarantee a soft selvedge. As a rule multifil threads are also employed as warp threads for seat belt webbing, resulting in the wanted soft selvedge of advantage in the edge portions. In another advantageous further embodiment of the method in accordance with the invention elastic threads are employed. This now makes it possible to produce elastic webbings for ready-to wear garments.
[0036] The object is furthermore achieved by a narrow fabric needle loom as it reads from claim 9 featuring a right-hand weft needle and a left-hand weft needle configured controllably simultaneously to each other, as well as a right-hand and a left-hand weft holdback for retaining and releasing the left-hand and right-hand weft thread respectively, and also being configured to work coordinated to each other, particularly working simultaneously with each other, and a reed. In a further advantageous aspect of the invention the narrow fabric needle loom is characterized in that the weft holdbacks are fixedly secured to the loom and that an elastic arrangement of stripper/holder wires is provided oriented preferably slightly towards the fell suitable for stripping off the weft thread loops before the shed change and before the fell from the weft holdbacks and retaining same by urging them to the fell until the reed itself beats up the weft threads. In this arrangement the narrow fabric needle loom in accordance with the invention may be additionally characterized in that the weft holdbacks are configured vertically pliant so that they are easily lifted by the tensioned weft threads in facilitating the sliding down of the weft threads.
[0037] With the narrow fabric needle loom in accordance with the invention the method in accordance with the invention for producing a seat belt webbing in accordance with the invention fabrication is now much simpler and with less wear and tear as is known in prior art. No catchment threads and no blocking threads now being needed to produce soft edges, this also eliminating the need for all of the equipment needed for this purpose in prior art. This greatly simplifies producing the seat belt webbing as compared to methods and devices as known from prior art. When employing hybrid threads as the weft threads thermosetting is done after weaving which, however, adds nothing to costs of the method as compared to prior art since any seat belt webbing, even when not made of hybrid weft threads, requires thermosetting to endow the seat belt webbing with the necessary shrinkage and stretch together with the wanted buffer for stretching thereof. Further advantages and features read from the sub-claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] For a better appreciation of the invention it will now be explained by way of two example aspects with reference to the drawings in which:
[0039] FIG. 1 is a diagrammatic, greatly magnified view of a seat belt webbing and salient parts of a narrow fabric needle loom as shown during a first step in the process in which the weft needles have entered the shed roughly by a third.
[0040] FIG. 2 is a diagrammatic, greatly magnified view of a seat belt webbing and parts of a narrow fabric needle loom as shown during a second step in the process in which the weft needles are fully retracted.
[0041] FIG. 3 is a diagrammatic, greatly magnified view of a seat belt webbing and parts of a narrow fabric needle loom as shown during a third step in the process in which the reed is just before the fell with the weft needles (again) fully retracted.
[0042] FIG. 4 is a view similar to that as shown in FIG. 1 but with an additionally employed monofil weft needle for picking a monofil thread.
[0043] FIG. 5 is a view corresponding to that as shown in FIG. 2 but showing use of an additional monofil weft needle.
[0044] FIG. 6 is a view analogous to that as shown in FIG. 3 but showing use of an additional monofil weft needle.
[0045] FIG. 7 is a greatly schematized view of a variant of a weft holdback fixedly secured to the loom and a reed moving thereon shown in the situation in which the weft needles are still located between reed and weft holdback, in a diagrammatic side view at an selvedge of the webbing.
[0046] FIG. 8 is likewise a diagrammatic view as shown in FIG. 7 of the configuration as just described but here at a later point in time in which a stripper or holder wire is in contact with the weft loop to shift it to the fell.
[0047] FIG. 9 is again a greatly magnified view of the situation as shown in FIG. 8 as viewed in the direction of the arrow DS of FIG. 8 .
[0048] FIG. 10 is a view of the reed as shown in FIGS. 7 and 8 by way of an example including an example of how the stripper or holder wire is arranged.
[0049] FIG. 11 is a diagrammatic top-down view of a webbing with picots at the edges.
[0050] FIG. 12 is another diagrammatic top-down view of an exploded detail of the webbing as shown in FIG. 11 to highlight production of the picots at the selvedges.
[0051] FIG. 13 is a diagrammatic side view of the weft holdback positions as employed in producing a webbing as shown in FIG. 11 and FIG. 12 .
[0052] FIG. 14 is a diagrammatic partial section view of a further example aspect of a device in accordance with the invention having a weft needle for two weft threads including an eyelet and a tucker.
[0053] FIG. 15 is a diagrammatic partial section view of a magnified detail X as shown in FIG. 14 from the side and in a top-down view.
[0054] FIGS. 16 a to 16 c are each a diagrammatic partial section view of a magnified detail X as shown in FIG. 14 from the side view in three different states X 1 to X 3 .
DETAILED DESCRIPTION
[0055] Referring now to FIG. 1 there is illustrated a seat belt webbing 2 the right and left-hand sides of which correspond to the right and left-hand sides of the drawing in accordance with the capital letters R and L evident encircled below FIG. 1 . This applies to all figures as discussed in the following. The seat belt webbing 2 is divided into three portions, a left-hand edge portion RL, an inner portion M and a right-hand edge portion RR. Arranged in each transition portion between the left-hand edge portion RL and inner portion M and between the inner portion M and the right-hand edge portion RR are so-called weft holdbacks SRHR (right-hand) and SRHL (left-hand) evident from FIGS. 2 and 3 by their retaining point symbolized by a thick, black dot. These retaining points are the auxiliary holdback points which by their function lead to each weft reversal points opposite the weft picking side which are located within the material of the seat belt webbing in accordance with the invention and thus “disappear”. Outside of these weft holdback positions simply the soft selvedge exists, indicated simply by a weft thread.
[0056] The situation as shown in FIG. 1 shows the weft needles SNL, SNR extended roughly by a third into the shed, whilst FIG. 2 already shows the final position of the weft needles in the fully picked position. By contrast, FIG. 3 shows the opposite situation with the weft needles SNL and SNR fully retracted and also the weft reversal points formed by the weft holdback function at the selvedge of the inner portion. It is evident from FIG. 3 how the reed WB is already advanced nearer to the picking zone which in the next step is advanced to the freshly picked weft threads as indicated by the arrow to be beaten up by the material indicated shaded as already being woven. In this arrangement the weft holdbacks briefly lose their function whilst the weft reversal positions are likewise removed therefrom. Shown in the figures, particularly in FIG. 1 , by way of example, on the right-hand side is a weft holdback SRHR in the shape of a sawtooth. In FIG. 1 the two weft threads SFR and SFL are shown as dots cross-sectionally just before being shifted by the motion of the weft needles onto the weft holdback SRHR in thus attaining the position as shown in FIG. 2 (right-hand side). Evident already from FIG. 3 (right-hand side) is the condition of the weft holdback SRHR in which the weft threads have been removed therefrom and bound to the material by the further action of the reed.
[0057] The method in accordance with the invention for weaving a seat belt webbing comprising an inner portion M, a soft right-hand edge portion RR and a soft left-hand edge portion RL, a right-hand weft thread SFR and a left-hand weft thread SFL, functions as a continuous repeat of a step sequence;
ar) picking the right-hand weft thread SFR from the right-hand side of the webbing into the right-hand edge portion RR and into the inner portion M by means of a right-hand weft needle SNR, al) picking the left-hand weft thread SFL from the left-hand side of the webbing into the left-hand edge portion RL and into the inner portion M by means of a left-hand weft needle SNL simultaneously to step ar), br) retaining the right-hand weft thread SFR in the transition portion from the inner portion M to the left-hand edge portion RL by means of a left-hand weft holdback SRHL, bl) retaining the left-hand weft thread SFL in the transition portion from the inner portion M to the right-hand edge portion RR by means of a right-hand weft holdback SRHR simultaneously to step br), cr) tucking the right-hand weft thread SFR with the left-hand weft holdback SRHL and returning the left-hand weft holdback SRHL into the vicinity of the fell BA, cl) tucking the left-hand weft thread SFL with the right-hand weft holdback SRHR and returning the right-hand weft holdback SRHR into the vicinity of the fell BA simultaneously to step cr), dr) returning the right-hand weft needle SNR to the right-hand side of the webbing, dl) returning the left-hand weft needle SNL to the left-hand side of the webbing simultaneously to step cr), e) stripping off the weft loops formed in the previous step from the two weft holdbacks SRHR, SHRL by the reed WB to the fell BA and forwarding the two weft holdbacks SRHR, SHRL away from the fell BA, f) beating up the two weft threads SFR, SFL by the reed (WB).
[0068] In steps cr) to e) the weft holdbacks are shuttled on a slight curve, in the forwards motion—away from the fell—the weft threads advanced by the weft needles slide down into place behind the angled upright hook tips into the gussets of the hooks of the weft holdbacks. In the backwards motion the holdbacks SRHL, SRHR move back, the weft needles SNL, SNR also being retracted, whereas the weft thread loops SFS remain hanging on the hooks. After shed closure the reed WB is forwarded, stripping off the weft thread loops and urging them to the fell (see also FIGS. 1 to 6 ).
[0069] When strongly reducing the inner portion in its width M, resulting in just a slim strip, whilst simultaneously strongly widening the edge portions RR, RL a webbing materializes totally different from that as described hitherto whose inner portion has the appearance of a thickened ridge. To offset any stresses having occurred the portions can be woven differingly, e.g. a plain 1 / 1 weave in the edge portions and panama 2 / 2 in the inner portion. Webbings can be produced highly cost-effectively to advantage even with a large overall width. Since the person skilled in the art is aware of how a narrow fabric needle loom works, details thereof are omitted in the following description. The main components of the seat belt webbing 2 in accordance with the invention namely warp threads KF and the weft threads SFR and SHL are clearly evident.
[0070] Referring now to FIGS. 4 to 6 there is illustrated a step sequence analogous to that as shown in FIGS. 1 to 3 with the addition of an extra supplementary monofil weft needle SNZ being shown in the method and device highlighted shaded. Referring now to FIG. 6 particular indication is made to the two weft reversal points SUL on the left-hand side and SUR on the right-hand side, resulting from activation of the weft holdbacks SRHR and SRHL. Evident from FIG. 5 in the region of the transition between the inner portion and the left-hand edge portion at the selvedge of the already finish-woven material is a point ZZ intended as an example for feed of the supplementary thread (SFZ) by means of a heddle or similar means. When tracing the steps of the second example aspect of a weaving method in accordance with the invention in making use of a needle for an additional weft thread as shown in FIGS. 4 to 6 , it is evident how as shown in FIG. 4 the weft needles have entered roughly by a third into the shed, FIG. 5 already showing the position of the weft needles after having fully penetrated the shed into the maximum retraction/end position. By contrast FIG. 6 shows the opposite maximum return position of the weft needles from the shed, the reed WB already being underway in a motion as indicated by the adjacent arrow to the already finished fabric or the weft threads in front thereof beaten up to the already finished material. In the next step the reed is again moved away from the fell and weft picking recommences from the start, resulting in the situation again as described in FIG. 4 , and so on. To advantage the edge portions RL and RR are just 4 to 8 warp threads “wide” so that the additional thread is hidden from external view, i.e. invisible in the selvedge of the seat belt webbing.
[0071] By the ways and means as just described the method in accordance with the invention in its advantageous further embodiment comprises the following further steps:
az) picking a monofil weft thread SFZ fed preferably in the transition portion from the inner portion M to the left-hand edge portion RL from left to right up to the transition portion from the inner portion M to the right-hand edge portion RR by means of a left-hand supplementary weft needle SNZ simultaneously to step ar) bz) retaining the monofil weft thread SFZ in the transition portion from the inner portion M to the right-hand edge portion RR by means of the right-hand weft holdback SRHR simultaneously to step cr), cz) tucking the monofil weft thread SFZ with the right-hand weft holdback SRHR and returning the right-hand weft holdback SRHR up to just before the fell BA simultaneously to the step cr) dz) returning the left-hand supplementary weft needle SNZ simultaneously to step dr).
[0076] It is, of course, just as possible to replace this aspect of the device in accordance with the invention and of the correspond method using the left-hand supplementary weft needle SNZ by a right-hand additional weft needle or analogous simultaneously, the resulting situation then being mirror inverse or symmetrical. When there is sufficient room in the shed a variant involving two additional weft needles—one on the right and one on the left—can be made use of to advantage. In the methods as described hitherto the weft holdbacks SRHL, SRHR are shuttled on a light curve. In the forwards motion thereof—away from the fell—the weft threads advanced by the weft needles slide down into place behind the angled upright hook tips into the gussets of the hooks (see FIGs.).
[0077] Referring now to FIG. 7 there is illustrated as an example and strongly diagrammatic, i.e. simply qualitatively, how at the fell BA the webbing 2 opens into a shed A-C formed by the warp threads KF. A hook-shaped curved needle, in this case a weft holdback SRH, fixedly secured to the loom is provided in the vicinity of the fell BA whereby the reed WB is just about to move in the direction of the arrow ZBA to position the weft threads SF as shown in FIG. 8 just before the fell BA by means of the stripper/holder wires FSDr which in the position as shown in FIG. 8 is just before the fell BA, the stripper/holder wires FSDr having contacted the weft threads SF in the position of the reed WB as shown in FIG. 8 . In further motion of the reed moving in the direction of the arrow ZBA it is elastically bent into the broken-line depicted position FSDr′ in thereby stripping the weft threads SF from the hook H of the weft holdback SRH when the reed beats up the weft thread at the fell BA (thus, practically simultaneously).
[0078] Referring now to FIG. 9 there is illustrated the situation as just described but now greatly magnified, showing just one selvedge of the seat belt webbing in accordance with the invention in conjunction with the sophistication of the present invention in accordance with the invention. The already finished-woven seat belt webbing 2 is evident from the lower portion in FIG. 9 . A selvedge is represented by a right-hand edge RR. Clearly evident is the reed WB mounting the stripper/holder wires FSDr shown in part section urging the weft thread loops SFS of the weft threads SF wrapping the hook H of the weft holdback SRH against the fell BA. The arrow ZBA indicates motion of the reed as just completed.
[0079] Referring now to FIG. 10 there is illustrated diagrammatic a front view of the reed WB as viewed in a direction from left to right in a view as shown in FIG. 7 . Clearly evident is the arrangement of the stripper/holder wire FSDr. It is emphasized that FIGS. 9 and 10 represent just sections of the right-hand edge portion of the seat belt webbing and, again, that there is no correlation between the dimensioning as shown in FIG. 9 and FIG. 10 .
[0080] Referring now to FIG. 11 there is illustrated very simplified diagrammatically the top-down view on a webbing 4 edged on both sides with picots 6 . Highlighted in FIG. 11 is a portion P extending in the direction of the warp thread as indicated by the arrow K which is exploded in FIG. 12 to detail how a weft thread of a right-hand weft needle is guided in this portion. The weft holdbacks whose function and arrangement was detailed previously in the embodiment of FIGS. 11 and 12 are arranged in the positions A and B located transversely to the width of the webbing. The weft holdback in position A works like a weft holdback in the examples as already described, namely within the two edges of the webbing and serving to hold back the weft thread SFR picked to the left by the right-hand weft needle (not shown) resulting in it forming a weft thread loop within the webbing as shown in position A. As compared to the example aspects described hitherto a second left-hand weft holdback SRHL 2 is additionally positioned at B as shown in FIGS. 11 and 12 . This retains the (right-hand) weft thread SFR as picked by the (right-hand) weft needle (not shown) until the weft needle has been retracted from the shed back into its starting position in moving the reed WB (not shown) shortly before the end of the shed to the fell in thus setting the weft thread loop PS for the picot in the position B, i.e. protruding beyond the left-hand edge of the 4. Producing picots 6 at the right-hand selvedge of the webbing is done analogously to that as said above concerning the left-hand webbing selvedge.
[0081] It is emphasized that to simplify its overview FIG. 12 does not show the left-hand weft thread SFL picked from the left simultaneously. In effect, the configuration of the right-hand weft thread SFR merely shown qualitatively to illustrate diagrammatically the warp thread length portion P, as shown in FIG. 11 , is understood to be bunched together in the warp direction, the train of a plurality of weft thread loops then resulting in the picot 6 and picot selvedge 8 respectively.
[0082] Referring now to FIG. 13 there is illustrated diagrammatically the two weft holdbacks as employed in the example aspects as shown in FIG. 11 and FIG. 12 , i.e. weft holdback SRHL in the position A and weft holdback SRHL 2 in position B located outside of the webbing 4 to be woven. The weft holdbacks are moved as indicated by the arrows VZ away from the fell BA and thereto. The weft holdback SRHL 2 is also operated in two positions Y (up when no picots are produced) and Z (down when picots are produced). If in an advantageous further aspect of the invention more than one double weft thread is to be simultaneously picked per side preferably partly in differing sheds, then it is of advantage to control the up and down motion of the weft holdbacks precisely (analogous to FIG. 13 , positions B: Y and Z) making it easier to tuck a stack of weft thread loops by the weft holdbacks.
[0083] Referring now to FIG. 14 there is illustrated a device in accordance with the invention for implementing a variant of the method in accordance with the invention in which the two weft threads SFL and SFR are picked by just one weft needle 28 (see FIG. 15 for details). In the region of its tip 34 the weft needle 28 has an eyelet 36 by means of which the first weft thread SFL is guided and shedded. Retracting the weft needle 28 from the shed results in a second (right-hand) weft thread SFR being tucked and shedded by means of a tucker 42 with a hook 40 which can be rotated into various locked positions.
[0084] FIG. 14 shows the position—here greatly magnified to make for a simplified illustration—of the weft needle 28 in which it sheds the left-hand weft thread SFL, the hook 40 having already passed by the right-hand weft thread SFR. Referring now to FIG. 16 there is illustrated how a pusher 30 is provided to urge the weft thread SFR into the path taken by the hook 40 on return of the weft needle 28 as indicated by the arrow RW ( FIGS. 16 a and 16 b ). In this arrangement the right-hand weft thread SFR is entrained by the hook 40 ( FIG. 16 a ) and guided by the weft needle 28 to beyond the left-hand weft holdback SRHL until the hook 40 by contacting in “overrunning” a stopper 32 fixedly mounted on the loom (see FIGS. 14 , 16 b and 16 c ) is turned against a spring latch 38 arranged in the weft needle 28 as shown by way of example in FIG. 15 to thereby “lose” the right-hand weft thread SFR ( FIG. 16 b ), ending the pick cycle. The next pick cycle begins with the forwards motion of the weft needle 28 as indicated by the direction of the arrow VW as shown in FIG. 16 c , here “overrunning” the stopper 32 fixedly connected to the loom ( FIGS. 14 , 16 b and 16 c )—but now in the opposite direction—causing the hook 40 to be repositioned for tucking.
[0085] The method as may be implemented, for example, by the device as shown in FIGS. 14 to 16 c as set forth in claim 22 for weaving a webbing, particularly a seat belt webbing comprising an inner portion M, a soft right-hand edge portion RR and a soft left-hand edge portion RL is characterized by a continuous repeat of a step sequence;
sal) picking the left-hand weft thread SFL from the left-hand side of the webbing into the left-hand edge portion RL and into the inner portion M by means of the weft needle 28 , sbl retaining the left-hand weft thread SFL in the transition portion from the inner portion M to the right-hand edge portion RR by means of a right-hand weft holdback SRHR, sr) tucking the right-hand weft thread SFR with the tucker 42 , sar) picking the right-hand weft thread SFR from the right-hand side of the seat belt webbing into the right-hand edge portion RR and into the inner portion M by means of the weft needle 28 , sbr) retaining the right-hand weft thread SFR in the transition portion from the inner portion M to the left-hand edge portion RL by means of a left-hand weft holdback SRHL, scr) tucking the right-hand weft thread SFR with the left-hand weft holdback SRHL and returning the left-hand weft holdback SRHL to the fell BA, scl) tucking the left-hand weft thread SFL with the right-hand weft holdback SRHR and returning the right-hand weft holdback SRHR to the fell BA particularly simultaneously to step cr), se) stripping off the weft loops formed in the previous step from the two weft holdbacks SRHL, SRHR by the reed WB to the fell BA and forwarding the two weft holdbacks away from the fell BA, f) beating up the two weft threads SFR, SFL by a reed WB.
It is emphasized that the method—as just described—can be implemented not just with one weft needle, variants thereof being possible with e.g. two dual weft needles the same or differing in length as well as in making use of further weft holdbacks as well as all combinations thereof. The person skilled in the art will readily appreciate that all selvedges known from prior art can be produced by the method in accordance with the invention.
[0095] In summary it is again pointed out that the invention now does away with the tuck and seal threads as well as the hardware therefor formerly always needed. As compared to prior art the invention provides a thinner webbing which especially with a softer selvedge makes for a great achievement as regards vehicular comfort. In addition to this, the webbing in accordance with the invention is more cost-effective in production than possible in prior art by saving steps in the method and components in the hardware involved. Furthermore, the present invention has the advantage that tensioning the weft thread is now substantially reduced in thus strongly diminishing the wear and tear and frequency of weft thread breakages and weft thread guide points. The knitting needles as needed in prior art and the fluffing associated therewith are now eliminated to advantage by the present invention.
LIST OF REFERENCE NUMERALS
[0000]
2 seat belt webbing
4 webbing
6 picot
22 webbing
28 weft needle
30 pusher
32 stopper
34 needle tip
36 eyelet
38 spring latch
40 hook
42 tucker
A-C shed
BA fell
DS arrow
FSDr stripper/holder wires
FSDr′ stripper/holder wires
H hook
KF warp threads
L (encircled) left-hand side
M inner portion
P picot portion
PS picot weft loop
R (encircled) right-hand side
RR right-hand edge portion
RL left-hand edge portion
SF weft thread
SFR right-hand weft thread
SFL left-hand weft thread
SFS weft thread loop
SFZ supplementary weft thread
SNR right-hand weft needle
SNL left-hand weft needle
SNZ left-hand supplementary weft needle
SRHL left-hand weft holdback
SRHL 2 second left-hand weft holdback
SRHR right-hand weft holdback
SRHR 2 second right-hand weft holdback
SUL left-hand weft reversal point
SUL right-hand weft reversal point
VZ arrow
WB reed
Y weft thread holdback position
Z weft thread holdback position
ZBA arrow | The invention relates to a method for weaving a webbing, comprising at least one first (right-hand) weft thread and at least one second (left-hand) weft thread, characterized in that the two weft threads are introduced into the same shed from both sides of the webbing, are wound around weft thread retainers in weft change loops, are substantially retained by the weft thread retainers until shed change and are then stripped off from the left thread retainers by the reed and after shed change and are bound against the stop. | 3 |
This application is a §371 of International Application No. PCT/EP2012/053077 filed Feb. 23, 2012, and claims priority from German Patent Application No. 10 2011 004 690.9 filed Feb. 24, 2011.
FIELD OF INVENTION
The invention relates to a force module for generating forces in a highly dynamic manner by assembling a plurality of piezo actuators for connecting to a voltage source and the use thereof.
BACKGROUND OF INVENTION
Piezo actuators in the form of piezoelectric low-voltage actuators, which are constructed in multi-layer design, are the current state of the art for generating forces in a highly dynamic manner. The working capability and therefore also the force capability are substantially determined by the volume of the piezo actuators which is subject to limits determined by the process. Forces which can typically be generated are of the order of magnitude of just a few kN.
Although higher forces can be achieved with piezo actuators in the form of the known high-voltage actuators which, on account of being constructed from discrete piezo discs, can be made significantly larger than piezoelectric low-voltage actuators, no spatial resolution can be achieved with these. Also, the high operating voltage does not allow them to be used in the harsh environment of mechanical engineering.
As relatively sensitive electro-ceramic materials are involved where piezo actuators are concerned, these cannot be used for the field of application according to the invention without further structural measures. Simply assembling several piezo actuators on one voltage source leads to uncontrolled electrical states (hot spots, serial failures due to the domino effect etc.).
SUMMARY OF INVENTION
Other systems based on hydraulic or electrodynamic principles either do not achieve the required high dynamics, the required spatial resolution or need high energy in order to maintain the forces. Special hydraulic cylinders are also eliminated on account of their too large installation dimensions.
The invention is based on the object of creating a force module which generates mechanical forces in the range of several 100 kN in a highly dynamic and spatially resolved manner. Response times which lie at least in the millisecond range are to be achieved and the spatial resolution is to take place at least in the square centimeter range.
It must also be possible to use the force module in an extremely demanding manufacturing environment, in which it is continuously subjected to and must be capable of withstanding external forces, in particular impact forces, of several 10 to 100 kN.
In order to guarantee a long life, the force module must also be reliably protected against environmental influences, for example moisture or chemical influences.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows the internal structure of a sub-module according to the present invention.
FIG. 2 is an external view of the sub-module of FIG. 1 .
FIG. 3 is a view of a force module according to the present invention along section A-A of FIG. 4 .
FIG. 4 is a view of a force module according to the present invention along section B-B of FIG. 3 .
DETAILED DESCRIPTION
According to the invention, this object is achieved in that the force module consists of at least two sub-modules, each having at least two piezo actuators and their electrical contacting elements, and a controlling and protection module for the piezo actuators in the sub-modules, wherein all electric contacting elements of the sub-modules are fed into the controlling and protection module. As a result, the force capabilities of the individual piezo actuators are added together and the high total forces according to the object can be achieved.
In a preferred embodiment, the electrical contacting elements provide two electrical printed circuit tracks for each individual piezo actuator in the sub-module, enabling each piezo actuator in the sub-module to be driven individually and independently from others.
Preferably, the electrical contacting elements are a flexible board with electrical printed circuit tracks and the outer electrodes of the piezo actuators are electrically connected to the printed circuit tracks. Flexible boards are extremely thin and therefore require little space. In addition, they can be fed out of a housing easily and in a sealed manner. A flexible board is understood to mean a flexible, electrically insulating, flat, thin carrier to which printed circuit tracks are applied.
Preferably, each flexible board is provided with a connecting plug at its end. This simplifies the electrical coupling of the sub-modules to the controlling and protection module.
In a preferred embodiment, each sub-module is enclosed and has a housing part with base plate and cover in order to protect the piezo actuators from environmental influences, and only the electrical contacting elements are fed out of the housing in a sealed manner. By this means, the sub-module is reliably protected against environmental influences.
In a preferred embodiment, ceramic materials are introduced between the piezo actuators in the sub-modules. This leads to better electrical insulation of the individual piezo actuators from one another.
Preferably, all sub-modules are constructed identically. This simplifies production.
Preferably, no electronic components are mounted in the sub-modules and these are arranged exclusively in the controlling and protection module instead. This measure enables the sub-modules to be made small and compact.
In an embodiment, a power amplifier for each individual piezo actuator is arranged in the controlling and protection module. In this way, in addition to the protection, a power amplifier is also provided for each individual piezo actuator, in which the electrical powers/currents required for driving the individual piezo actuators are controlled by means of transistors. As the individual piezo actuators can be addressed individually, the force module is able to realize almost any dynamic force distributions.
The monitoring and control of the device is carried out by means of easily manageable control signals which are produced by a control unit, e.g. a computer, and fed into the controlling and protection module by means of a data bus, which constitutes a major advantage.
Preferably, the force module has a force module housing part with base plate and cover plate and all parts are made of steel, in particular hardened steel. By this means, the sensitive piezo actuators and the electronic components are permanently protected against high mechanical loads.
Preferably, the sub-modules in the force module housing part with the base plate and cover plate are pre-stressed by means of expansion screws, as a result of which no tensile forces are introduced into the piezo actuators.
Preferably, a connecting cable, the electrical conductors of which are fed into the controlling and protection module, is connected to the force module. Preferably, a bus cable is also fed into the controlling and protection module.
Preferably, the force module according to the invention is used for controlling flow processes by means of local clamping in mechanical forming processes in the automobile industry.
The invention is characterized in that a certain number of piezo actuators, in particular piezoelectric multi-layer actuators, are assembled to form a sub-module and these sub-modules are assembled and arranged in a defined manner to form a force module consisting of a plurality of sub-modules. As a result, the force capabilities of the individual piezo actuators are added together and high total forces can be achieved.
The piezo actuators in the sub-modules can be driven individually and independently of one another in a highly dynamic manner, as a result of which a high spatial resolution is achieved.
The sub-modules are structurally designed such that they guarantee the electrical insulation of the individual piezo actuators and ensure a reliable protection against environmental influences.
In addition to the sub-modules, the force module contains a controlling and protection module, with which the piezo actuators of the sub-modules are individually electrically driven and protected and in this way controlled and managed electrical states are achieved.
The force module is designed so that it guarantees the mechanical protection of the sub-modules and of the controlling and protection module against high impact loads in operation for example.
A possible embodiment of the invention consists in that the sub-modules contain ten piezoelectric multi-layer actuators which are arranged in a row and can be driven individually. A different arrangement with a different number of individual piezo actuators is, of course, also possible, e.g. in the form of a 3×3 or N×N matrix arrangement.
In this embodiment, the piezo actuators are standard actuators, such as those used in common rail diesel injectors for example.
Contact with the individual piezo actuators is achieved by means of flexible board printed circuit tracks, e.g. by means of flexible boards to which printed circuit tracks are applied, or similarly space-saving methods with which, at the same time, the connecting and assembly effort can also be significantly reduced. This constitutes a decisive advantage compared with conventional contact methods, for example with individual connecting leads.
The use of a plurality of sub-modules in the force module has the decisive advantage that, purely statistically, a relatively high output as well as a low probability of failure is ensured. Each individual sub-module is tested before installation in the force module.
As an example, with an output probability or probability of survival of the individual piezo actuator of 99%, the output probability or probability of survival in a system of N piezo actuators is 0.99 N , that is to say with N=100, for example, only 37%. In a system of M sub-modules, it is therefore 0.99 M . With M=10, it is a significantly higher 90%.
Furthermore, the electrical decoupling of the individual piezo actuators in the sub-module has the advantage that each piezo actuator can be driven singly and individually. This prevents a serial failure as a result of a domino effect.
In addition, the ability to check each individual piezo actuator, for example during assembly or in operation, is guaranteed. A failed piezo actuator in a sub-module can therefore be localized and at least partially compensated for, i.e. the functionality of the sub-module can be maintained by appropriate control of the other piezo actuators.
The piezo actuators can be checked by conventional methods, such as impedance or charge analysis for example.
The piezo actuators are arranged in a row on a base plate, for example made of hardened steel, of the sub-module and aligned thereon by means of suitable tools, thus ruling out incorrect positioning of individual piezo actuators.
For further enclosure of the piezo actuators, a housing part, which encloses the row of piezo actuators, is arranged on the base plate. As an example, this housing part consists of a folded sheet metal part and has a cutout for the flexible printed circuit tracks. A cover is located on the housing part, thus ensuring a complete enclosure or encapsulation of the piezo actuators overall.
For better electrical insulation of the individual piezo actuators with respect to one another within the sub-module, electrically insulating components or substances, for example made of ceramic materials, are fitted between the piezo actuators. In a preferred embodiment, these are thin plates made of aluminum oxide. However, they can also be other ceramic materials or ceramic particles which are incorporated in the casting compound, or separate films of materials with a high dielectric strength. In the event of a flashover of an individual piezo actuator, this has the advantage that the damage does not affect the adjacent piezo actuators and the sub-module remains functional, i.e. intact.
The piezo actuators in the sub-modules are encapsulated to protect against environmental influences, for example against chemical substances or moisture. Casting compounds, for example made of silicone, polyurethane or epoxy resin, are suitable for this purpose. The casting compound fixes base plate, piezo actuators, housing part and cover.
The sub-modules constructed in this way are electrically connected to the controlling and protection module, for example by flexible printed circuit tracks with integral connecting plugs. The separation of the sub-modules from the controlling and protection module has the decisive advantage that the sub-modules can be made very compact, as no additional electronic components, such as for example electrical protection (e.g. mini fuses, PTC elements, zener diodes or other protection elements), have to be fitted to the piezo actuators. The individual fusing of the piezo actuators, which is necessary to prevent a complete failure of the sub-module in the event of a failure of one piezo actuator, is therefore carried out in a separate modular unit.
In an embodiment, in addition to the protection, the controlling and protection module also contains a power amplifier for each individual piezo actuator, in which the electrical powers/currents necessary for driving the individual piezo actuators are controlled by means of transistors. The individual piezo actuators can be addressed individually and therefore the force module according to the invention is able to realize almost any dynamic force distributions.
The monitoring and control of the force modules is carried out by means of easily manageable control signals which are produced by a control unit, e.g. a computer, and fed to the controlling and protection module by means of a data bus, which constitutes a major advantage.
The associated circuit technology is based on the known principles of power amplifier technology.
In a simpler variant, one sub-module is in each case driven by one power amplifier. This simplifies the construction.
In an even simpler variant, the controlling and protection module contains only fuses and surge arresters. In this case, when the whole force module is driven as one unit or the individual sub-modules are driven, the individual control lines can be fed to the outside and an external power amplifier connected. However, it would then no longer be possible to address the piezo actuators individually.
According to the invention, the sub-modules and the controlling and protection module are combined to form one force module.
The invention is explained further below with reference to figures.
A sub-module 21 is shown in FIGS. 1 and 2 , wherein FIG. 1 shows the internal structure and FIG. 2 an external view. In the embodiment shown here, five piezo actuators 1 are arranged in a row inside the sub-module 21 . The internal electrodes (not shown) of each polarity of the piezo actuator are connected in parallel by means of external electrodes 1 b . The piezo actuators 1 are all multi-layer actuators.
A flexible board 2 with printed circuit tracks 2 b is in each case soldered to the external electrodes 1 b of one polarity. Here, each external electrode 1 b of each piezo actuator 1 is associated with a printed circuit track 2 b on the flexible board 2 . The solder connection (vias with through-connection) for electrically connecting the external electrodes 1 b to the printed circuit track 2 b is identified by the reference 3 . The solder connection (vias with through-connection) for mechanically connecting the external electrodes 1 b to the flexible board 2 , i.e. the stabilizing of the piezo actuator/flexible board arrangement, is identified by the reference 5 .
As well as the printed circuit tracks 2 b , a ground connection 4 is also provided on the flexible board 2 . Each flexible board 2 is arranged with a connecting plug 9 (shown only schematically here) at its end.
FIG. 2 shows a sub-module 21 from the outside. Each sub-module 21 is enclosed and consists of a housing part 7 , a base plate 6 and cover 8 . Only the flexible board 2 with the printed circuit tracks 2 b is fed out of the housing, namely in a sealed manner, so that no environmental influences can find their way into the housing.
A force module 20 according to the invention is shown in FIGS. 3 and 4 . FIG. 3 shows the section A-A of FIG. 4 and FIG. 4 shows the section B-B of FIG. 3 .
The force module 20 consists of six sub-modules 21 , which have been inserted or plugged into the housing of the force module 20 , wherein in each case three sub-modules are arranged next to one another. Overall, this therefore results in a force module 20 with sixty piezo actuators 1 . The individual sub-modules 21 are all in electrical contact with the controlling and protection module 16 . More or fewer sub-modules 21 can of course also be combined in any way to form a force module 20 .
The force module 20 has the task of permanently protecting the sensitive piezo actuators 1 and the electronic components in the controlling and protection module 16 against high mechanical loads and, in the exemplary embodiment, consists of a solid base plate 10 and cover plate 12 made of steel, for example hardened steel, and a likewise solid force module housing part 11 .
The cover plate 12 is structurally designed so that it is fed through the force module housing part 11 during assembly. This is realized here by a peripheral recess. A sealing means, here an O-ring 15 which protects the force module housing part 11 against environmental influences, is additionally located in this recess.
Holes 13 , which each have a thread 14 and are arranged uniformly around the periphery of the force module 20 , are located in the cover plate 12 , in the force module housing part 11 and in the base plate 10 . In this exemplary embodiment, ten holes 13 are sufficient. They are used for accommodating expansion screws 24 , with which the sub-modules 21 are pre-stressed in the force module 20 and by means of which the three components 10 , 11 , 12 of the housing are securely joined to one another.
The expansion screws 24 act with a constant force on the sub-modules 21 , pre-stress these and prevent tensile forces being introduced into the piezo actuators 1 . The sizing of the expansion screws 24 with regard to their stiffness and position must be chosen so that the piezo actuators 1 have a sufficiently high expansion.
As the piezo actuators 1 can have slightly different heights for process reasons, they must be compressed during the assembly of the force module 20 . In doing so, the piezo actuators 1 themselves must not topple over and, at the end of the assembly process, must all be in firm contact with the cover plate 12 of the force module 20 , as otherwise the functionality of the force module 20 will not be guaranteed.
Advantageously, the cover plate 12 is assembled in such a way that, in a first step, the cover plate 12 is carefully moved as far as the stop by means of a suitable press device, i.e. the cover plate 12 rests immediately on the force module housing part 11 . The expansion screws 24 with defined stiffness which are fitted around the periphery of the force module are then tightened to a defined torque and the press device subsequently released. The piezo actuators spring back in the range of a few micrometers and an air gap is produced between cover plate 12 and force module housing part 11 .
Advantageously, this provides ideal protection for the force module in the event of high mechanical loads, e.g. typical impact loads, which occur with metal forming processes. In the extreme case, the cover plate 12 goes as far as the stop position with the force module housing part 11 , the air gap closes, thereby limiting the compression of the piezo actuators 1 , and prevents them from being damaged.
The process of assembling the force module 20 , in particular whether all piezo actuators are in force contact with the cover plate 12 , can be checked by the impedance or charge monitoring method already mentioned.
The electrical circuit in the controlling and protection module 16 is designated by the reference 17 , and the media-tight gland of the connecting cable 19 in the force module 20 by the reference 18 . In an embodiment, a power amplifier 23 for each piezo actuator 1 (only indicated in a general way) can also be arranged in the controlling and protection module 16 . | The invention relates to a force module ( 20 ) for generating forces in a highly dynamic manner by assembling a plurality of piezo actuators ( 1 ) for connecting to a voltage source. To enable the force module ( 20 ) to generate forces in the range of a few 100 kN in a highly dynamic and spatially resolved manner, according to the invention it is proposed that the force module ( 20 ) consists of at least two sub-modules ( 21 ), each having at least two piezo actuators ( 1 ) and their electrical contacting elements, and a controlling and protection module ( 16 ) for the piezo actuators ( 1 ) in the sub-modules ( 21 ), wherein all electric contacting elements of the sub-modules ( 21 ) are fed into the controlling and protection module ( 16 ). | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This patent application claims priority to U.S. Provisional Patent Application Ser. No. 60/637,170 filed Dec. 17, 2004.
BACKGROUND OF THE INVENTION
[0002] A major problem associated with current heating, ventilation and air conditioning (“HVAC”) systems is that it is very difficult to customize non-safety timing values once a controller for an HVAC system is installed in the field for a particular application.
[0003] Examples of such timing values include, but are not limited to, the temperature differential for water heater applications and air circulator blower delay times for furnace applications.
[0004] Although the ability to ascertain real-time data from an HVAC system as well as view historical data, it is very difficult to quickly ascertain exactly when certain problems and defaults have occurred without going back through a tremendous amount of data. It is the timed pattern of problems and defaults that typically provide clues as to causation. By having a service technician forced to look at a tremendous amount of recorded historical data will prevent him or her from readily diagnosing malfunctions and problems.
[0005] Another problem involving HVAC systems is the need for the service technician to obtain pertinent information to complete the task at hand without disturbing building owners or building operators. Also, there may be a need to perform research by the service technician to complete his or her job. Information of this nature can include the end user, the service company, the HVAC system manufacturer and information regarding a controller for the HVAC system.
[0006] An example of a furnace diagnostic system having the above deficiencies is described in U.S. Pat. No. 6,658,372, which issued on Dec. 2, 2003, to Robertshaw Controls Company, incorporated herein by reference, and also U.S. Pat. No. 6,535,838, which issued on Mar. 18, 2003, to Robertshaw Controls Company, incorporated herein by reference.
[0007] The present invention is directed to overcoming one or more of the problems set forth above.
SUMMARY OF INVENTION
[0008] In one aspect of this invention, a heating, ventilation and air conditioning diagnostic system is disclosed. This system includes a controller for operating a heating, ventilation and air conditioning system, a plurality of sensors for monitoring various parameters associated with the operation of the heating, ventilation and air conditioning system that are in electronic communication with the controller, at least one input device that is in electronic communication with the controller, wherein the at least one input device is able to modify variables utilized by the controller to improve performance of the heating, ventilation and air conditioning system, and at least one output device that is in electronic communication with the controller.
[0009] Another aspect of this invention is that a heating, ventilation and air conditioning diagnostic system is disclosed. The system includes a controller for operating a heating, ventilation and air conditioning system, a plurality of sensors for monitoring various parameters associated with the operation of the heating, ventilation and air conditioning system that are in electronic communication with the controller, wherein data from the plurality of sensors can be recorded in the controller, at least one input device that is in electronic communication with the controller, wherein the at least one input device is able to modify variables utilized by the controller to improve performance of the heating, ventilation and air conditioning system, and at least one output device that is in electronic communication with the controller.
[0010] Yet another aspect of this invention is that a heating, ventilation and air conditioning diagnostic system is disclosed. The system includes a controller for operating a heating, ventilation and air conditioning system and the controller is in electronic communication with a plurality of counters, a plurality of sensors for monitoring various parameters associated with the operation of the heating, ventilation and air conditioning system that are in electronic communication with the controller, wherein data from the plurality of sensors can be recorded in the controller, at least one input device that is in electronic communication with the controller, wherein the at least one input device is able to modify variables utilized by the controller to improve performance of the heating, ventilation and air conditioning system, and at least one output device that is in electronic communication with the controller.
[0011] In yet another aspect of this invention, a method for utilizing a heating, ventilation and air conditioning diagnostic system is disclosed. The method includes utilizing a controller for operating a heating, ventilation and air conditioning system, monitoring various parameters from a plurality of sensors associated with an operation of the heating, ventilation and air conditioning system that are in electronic communication with the controller, providing electronic communication between at least one input device and the controller, providing electronic communication between at least one output device and the controller, and modifying variables utilized by the controller with the at least input device to improve performance of the heating, ventilation and air conditioning system.
[0012] In another aspect of the present invention, a method for utilizing a heating, ventilation and air conditioning diagnostic system is disclosed. The method includes utilizing a controller for operating a heating, ventilation and air conditioning system that is in electronic communication with a plurality of counters, monitoring various parameters from a plurality of sensors associated with an operation of the heating, ventilation and air conditioning system that are in electronic communication with the controller, recording data from the plurality of sensors in the controller, providing electronic communication between at least one input device and the controller, providing electronic communication between at least one output device and the controller, and modifying variables utilized by the controller with the at least input device to improve performance of the heating, ventilation and air conditioning system.
[0013] These are merely some of the innumerable aspects of the present invention and should not be deemed an all-inclusive listing of the innumerable aspects associated with the present invention. These and other aspects will become apparent to those skilled in the art in light of the following disclosure and accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0014] For a better understanding of the present invention, reference may be made to the accompanying drawings in which:
[0015] FIG. 1 is a block diagram of a diagnostic system for a heating, ventilation and air conditioning system (HVAC) in accordance with the present invention;
[0016] FIG. 2 is a graphical user interface screen that illustrates various system inputs and outputs for a controller of the heating, ventilation and air conditioning system (HVAC) in accordance with the present invention; and
[0017] FIG. 3 is a graphical user interface screen that visually illustrates a component, e.g., furnace, of the heating, ventilation and air conditioning system (HVAC) and associated inputs and outputs in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0018] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures and components have not been described in detail so as to obscure the present invention.
[0019] Referring now to FIG. 1 , the present invention is directed to an electronic control system 10 for a heating, ventilation and air conditioning (“HVAC”) system. For the purposes of this patent application an HVAC system is broadly defined as system of heating, ventilation, evaporative cooling and/or air conditioning components, water heaters, as well as any combination thereof.
[0020] The electronic control system 10 includes at least one component of an HVAC system, e.g., furnace, which is generally indicated by numeral 20 . A controller is generally indicated by numeral 30 . The controller 30 can include a single processor or a whole series of processors and any variant of a processor such as a computer or a programmable logic controller.
[0021] The controller 30 is connected to at least one component 20 , e.g., plurality of components, through any form of electronic communication 100 . Also, the controller 30 can be an integral aspect of a particular component 20 , e.g., furnace. This can include a hardwired connection indicated by solid lines or wireless communication indicated by dotted lines. This can also include a computer network. Preferably, the computer network is local in nature such as a local area network (LAN). However, a wide area network (WAN) and other types of computer networks are possible.
[0022] When using a LAN networking environment, the controller 30 is connected to the LAN through a network interface or adapter. When using a WAN networking environment, the controller 30 typically includes a modem or other means for establishing communications over the WAN, such as a global computer network e.g., the Internet. The WAN network permits communication to other points or systems with a more comprehensive computer network. The computer network is capable of communicating in a wide variety of methods including, but not limited to, point-to-point, star, mesh or star-mesh architecture. The protocols utilized can include, but are not limited to, proprietary, Internet, contention and polled protocols and their derivatives. Communication protocols can also include, but are not limited to, RS485 and RS232.
[0023] As an optional embodiment, additional processing capability 52 can be connected in electronic communication to the controller 30 . An illustrative, but nonlimiting example, of this type of additional processing capability 52 includes a daughter board. This electronic communication 100 can be in the form of either hard-wired, wireless-type communication and any variant thereof.
[0024] Each component 20 preferably, but not necessarily, is in electronic communication 100 with a plurality of inputs 62 , e.g., sensors. There are input and/or output devices 50 , 40 in electronic communication 100 with the electronic control system 10 . This can include an input and/or output device 50 that is connected via hardwired connections to the controller 30 . Optionally, the input and/or output device 40 that is connected via wireless communication to the controller 30 .
[0025] Although a thermostat is preferred, the input and/or output devices 50 , 40 can include virtually any type of electronic output device. Preferably, but not necessarily, the electronic output device includes an electronic display 102 , as shown in FIG. 2 . Although a liquid crystal diode display is preferred for the electronic display 102 , a cathode ray tube, a plasma screen and virtually any other type of electronic display will suffice. The electronic display 102 can be hard wired, portable or in wireless connection with the controller 30 and any combination thereof.
[0026] The input and/or output devices 50 , 40 can also include an alarm to detect abnormal operating conditions or failures on part of the subsystems that can be visual or audible or both visual and audible. The alarm can be both local or over a computer network. If the alarm is over a computer network then nodes on the computer network will be able to visually or audibly indicate the alarm condition through controlled systems, subsystems and processes. Use of a wide area network, WAN, will permit safety and lower level alarm conditions to reach nodes that can provide an emergency response, monitoring services, owners, operators, repair and servicing organizations, and so forth. In premise nodes, such as that found on a local area network, LAN, the input and/or output devices 50 , 40 can include, in addition to a thermostat, appliances, messaging terminals, personal computers, televisions, auxiliary smoke and fire monitors, and alarm mechanisms, and so forth.
[0027] Moreover, the input and/or output devices 50 , 40 can include any type of pushbutton entry system including, but not limited to, a keyboard, voice recognition, and so forth. This can include, but is not limited to, a television set interface, and a security alarm display. Specifically the wireless input and/or output devices 40 can include, but are not limited to global computer network enabled appliance, e.g., web appliance, telephone (wired or wireless), personal digital assistant (“PDA”), laptop computer, home control interface and a wide variety of devices that use Wireless Application Protocol (“WAP”). WAP is a secure specification that allows users to access information instantly via handheld wireless devices. Wireless communication can also include infra-red communications.
[0028] Information from the plurality of inputs 62 , e.g., sensors, can be recorded as historical data in the controller 30 as well as accessed and viewed in real-time with the input and/or output device 50 , 40 . Illustrative, but nonlimiting examples of this type of read-only data includes: status of a thermostat or a plurality of terminals for a thermostat and associated fuse status; a pressure switch input status; a high limit switch input status; a rollout switch input status; an inducer relay status; a gas valve relay status; a circulation blower relay status; a circulation blower heat relay status; a circulation blower cool relay status; an igniter triac status; a current mode for the controller 30 ; an igniter active line counts; and a time left auto-reset timer. A listing of these preferred inputs are listed below in Table 1. The access indication “R” means that the user through the input and/or output devices 50 , 40 can only view the status of an input or output devices 50 , 40 for the controller 30 and cannot change it.
TABLE 1 Access Inputs and Outputs for Controller 30 R Thermostat (Terminal W) Status R Thermostat (Terminal Y) Status R Thermostat (Terminal G) Status R Thermostat (Terminal R) Status and Fuse Status R Pressure Switch Input Status R High Limit Switch Input Status R Rollout Switch Input Status R Inducer Relay Status R Gas Valve Relay Status R Circulation Blower Relay Status R Circulation Blower Heat Relay Status R Circulation Blower Cool Relay Status R Igniter Triac Status R Current Mode of Controller 30 R Igniter Active Line Counts R Time Left Auto-Reset Timer
[0029] An aspect of the present invention is information that can be stored in memory for the controller 30 and either accessed and in some instances accessed and modified through the input and/or output devices 50 , 40 . Illustrative, but nonlimiting examples of read-only data of this type includes: controller 30 information, e.g., manufacturing identification of the controller 30 , model number of the controller 30 , serial number of the controller 30 , software revision of the controller 30 , and a date code for the controller 30 , e.g., date of origination for the controller 30 , and system manufacturing information for the controller 30 .
[0030] Illustrative, but nonlimiting examples of this type of data that can be read as well as modified includes: dealer information for the component 20 , e.g., furnace. Nonlimiting examples of this type of information includes name of a dealer, phone number of a dealer, installation date for the component 20 , e.g., furnace, and service dates for the component 20 , e.g., furnace, and customer information, e.g., customer's name, address and zip code.
[0031] A listing of this data is provided below in Table 2. The access indication “R” means that the user through the input and/or output devices 50 , 40 can only view the value and cannot change it. Access indication “W” indicates that the user through the input and/or output devices 50 , 40 can alter the value to any desired value.
TABLE 2 Access Command Purpose R, W Customer Name, Address and Zip Code Information R Controller Manufacturing Information Identification, Model Number, Serial Number, Software Revision, and Date Code R, W Dealer Information Name, Phone Number, Installation and Service Date R System System Manufacturing Information Manufacturing Information
[0032] Another aspect of this Invention is that information from the plurality of inputs 62 , e.g., sensors, can be tallied or summed through counting-type electronic devices, e.g., counters.
[0033] Illustrative, but nonlimiting examples of this type of summed or tallied read-only data includes: a total number of heating cycles from flame detected to the flame not being present; a current mode of the controller 30 ; a total number of cooling cycles from when cooling is detected to when cooling is no longer present (such as found by detecting electrical power to the compressor from a specific terminal on the thermostat); and a current time stamp for the electronic control system 10 .
[0034] Illustrative, but nonlimiting examples of this type of summed or tallied data that can be read as well as the counter, timer or event tally reset to zero (0) includes: a total number of the heating cycles since the counter or tally is cleared; a total number of the cooling cycles since the counter or tally is cleared; a number of pressure switch openings after a flame is sensed since the counter or tally is cleared; a number of high limit switch openings since the counter or tally is cleared; a number of rollout switch openings since the counter or tally is cleared; a number of internal resets since the counter or tally is cleared; an average time for a heating cycle; an average time for a cooling cycle; an average number of reset commands since the system has been cleared; and a failure history with a previous predetermined number, e.g., 20 , of failures indicated with a time stamp.
[0035] Illustrative, but nonlimiting examples of this type of summed or tallied data that can be read as well as set to a desired value by the user, includes: at least one timing delay for turning the heat on; at least one timing delay for turning the heat off; at least one timing delay for turning the cooling on; and at least one timing delay for turning the cooling off.
[0036] A listing of this timer data is provided below in Table 3. The access indication “R” means that the user through the input and/or output devices 50 , 40 can only view the value and cannot change it. Access indication “W” indicates that the user through the input and/or output devices 50 , 40 can alter the value to any desired value. The access indication “Z” means that the user through the input and/or output devices 50 , 40 can reset the counter, timer or event tally to zero (0).
TABLE 3 Access Property Name R Total Number of Heating Cycles (Flame Detected To Not Flame Present) R Total Number of Cooling Cycles (Power to Terminal Y Detected To Power Applied to Terminal Y Not Present) R, Z Total Number of Heating Cycles Since Cleared R, Z Total Number of Cooling Cycles Since Cleared R Current Mode of the Controller 30 R, Z Number of Pressure Switch Openings After a Flame is Sensed R, Z Number of High Limit Switch Openings R, Z Number of Rollout Switch Openings R, Z Number of Internal Resets R, Z Average Time for a Heating Cycle R, Z Average Time for a Cooling Cycle R, Z Number of Reset Commands Since the System Has Been Cleared R, W Heat On Delay Timing R, W Heat Off Delay Timing (Number 1) R, W Heat Off Delay Timing (Number 2) R, W Heat Off Delay Timing (Number 3) R, W Heat Off Delay Timing (Number 4) R, W Cool On Delay Timing R, W Cool Off Delay Timing (Number 1) R, W Cool Off Delay Timing (Number 2) R Current System Time Stamp R, Z Failure History - Previous Predetermined Number of Errors With Time Stamp
[0037] Referring now to FIG. 2 , the electronic display 102 can provide a graphical user interface screen 104 that provides a significant amount of visual information for the user. In an illustrative, but nonlimiting example, a graphical user interface screen 104 for a furnace system is depicted. There are click-on tabs for the graphical user interface screen 104 for the user to access other portions of the software with examples being a file function 108 , a configure function 110 , a data function 112 and a help function 114 .
[0038] There is a listing of running counters indicated by numeral 120 . Illustrative, but nonlimiting examples of these counters include: a total number of heating cycles from flame detected to the flame not being present 122 ; a total number of cooling cycles from when cooling is detected to when cooling is no longer present (such as found by detecting electrical power to the compressor from a specific terminal on the thermostat) 124 ; a total number of the heating cycles since the counter or tally is cleared 126 ; a total number of the cooling cycles since the counter or tally is cleared 128 ; a number of pressure switch openings after a flame is sensed since the counter or tally is cleared 130 ; a number of high limit switch openings since the counter or tally is cleared 132 ; a number of rollout switch openings since the counter or tally is cleared 134 ; a number of internal resets since the counter or tally is cleared 136 ; an average time for a heating cycle 138 ; an average time for a cooling cycle 140 ; an average number of external reset commands since the system has been cleared 142 ; an number of time the ignition retried 144 and the number of ignition recycles 146 . There is verbiage indicating whether the counters are to be displayed on the graphical user interface screen 160 and an associated visual indicator 161 .
[0039] There is a display for inputs indicated by numeral 162 . Illustrative, but nonlimiting examples of these inputs include: an indication that a pressure switch is activated 164 ; an indication that a rollout switch is activated 166 ; an indication that a high limit switch is activated 168 ; an indication of power being applied to a particular terminal, e.g., “R”, for a thermostat 172 ; an indication of power being applied to a particular terminal, e.g., “G”, for a thermostat 174 ; an indication of power being applied to a particular terminal, e.g., “Y”, for a thermostat 176 ; and an indication of power being applied to a particular terminal, e.g., “W”, for a thermostat 178 . There is also a graphical indication of a series of delay timers being on or off as indicated by numeral 180 .
[0040] There is a display for outputs indicated by numeral 182 . Illustrative, but nonlimiting examples of these outputs include: a circulation blower for heating being operational 184 ; a circulation blower for cooling being operational 186 ; a circulation blower being operational at a low level 188 ; an indication that a gas valve is operational 190 ; an indication that an inducer is operational 192 ; and an indication of an igniter state 194 .
[0041] There is a display for general information indicated by numeral 200 . Illustrative, but nonlimiting examples of this type of information includes: a control mode 201 , e.g., monitor a burner; igniter line counts 202 , e.g., 40 ; and reset time remaining 204, e.g., zero.
[0042] There is a display representing an indication of furnace flame strength indicated by numeral 222 . There is a graphical representation of a meter indicated by numeral 224 . There is also verbiage that indicates that a weak flame is below a certain predetermined value, e.g., 226 .
[0043] There is a display for communication settings indicated by numeral 150 . This includes a visual display as to whether the screen update feature 152 is indicated as being on or off 154 . There is a visual indication 156 that indicates whether a controller 30 is in electronic communication 100 with an input and/or output devices 50 , 40 .
[0044] Also present on the graphical user interface screen 104 is a device for reviewing historical data from the electronic control system 10 that is generally indicated by numeral 205 . This includes a graphical interface pushbutton for a fast rewind of the historical data 206 , a graphical interface pushbutton to stop playing the historical data 208 , a graphical interface pushbutton to play the historical data 210 , a graphical interface pushbutton to pause recording the historical data 216 and a graphical interface pushbutton for recording of the historical data 218 . There is also a visual indicator for the specific function that is currently activated 212 , e.g., stop, rewind, play, pause, fast forward or record. There is a graphical user interface pushbutton 220 to seek a particular hour of recorded historical data. There is also a multiplier function 214 to speed or slow down the recording and playback of historical data from the electronic control system 10 by a predetermined factor.
[0045] Information from the plurality of inputs 62 , e.g., sensors, viewed in real-time with the input and/or output devices 50 , 40 , shown in FIG. 1 , is preferably, but not necessarily, displayed with a graphical user interface screen 160 that replicates at least one component 20 , e.g., furnace, and at least one of the plurality of inputs 62 , e.g., sensors in FIG. 3 . This graphical user interface screen 160 is generally indicated by numeral 300 . There is a visual indicator 304 providing connection status between the controller 30 and an input and/or output devices 40 , 50 . There is a visual indicator 306 signifying if a pressure switch is open or closed. Also, there is a visual indicator 308 signifying if a high limit switch is open or closed. Furthermore, there is a visual indicator 310 signifying if a rollout switch is open or closed.
[0046] There is also a graphical representation of at least one component 20 , e.g., furnace, indicated by numeral 302 . Components of an illustrative furnace may include a first air circulator blower 312 , an air duct 314 , a gas valve 316 , igniters 318 and a second air circulator blower 322 . There is an icon for obtaining system information 324 and an icon for saving data 336 . There is also a graphical representation of a control circuitry 320 for the at least one component 20 , e.g., furnace.
[0047] In addition, there is the previous system for reviewing historical data from the electronic control system 10 (as shown in FIG. 1 ) that is generally indicated by numeral 205 . This includes a graphical interface pushbutton for a fast rewind of the historical data 206 , a graphical interface pushbutton to stop playing the historical data 208 , a graphical interface pushbutton to play the historical data 210 , a graphical interface pushbutton to pause recording the historical data 216 and a graphical interface pushbutton for recording of the historical data 218 . There is also a visual indicator for the specific function that is currently activated 212 , e.g., stop, rewind, play, pause, fast forward or record. There is also a multiplier function 214 to speed or slow down the recording and playback of historical data from the electronic control system 10 by a predetermined factor, e.g., 64.
[0048] In addition in FIG. 3 , there is a visual representation 332 of an input and/or output devices 50 , 40 . An illustrative, but nonlimiting, example of an input and/or output devices 50 , 40 includes a digital thermostat 332 . There is a visual indicator 330 signifying whether heating is operational, a visual indicator 328 signifying whether cooling is operational and a visual indicator 326 signifying whether a fan is operational. Also, there is a visual indicator 334 indicating whether electrical power has been applied to the input and/or output devices 50 , 40 , e.g., digital thermostat 332 .
[0049] The preferred embodiment of the present invention and the method of using the same has been described in the foregoing specification with considerable detail, 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 performed 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 heating, ventilation and air conditioning diagnostic system and associated method of use is disclosed. The system includes a controller for operating a heating, ventilation and air conditioning system, a plurality of sensors for monitoring various parameters associated with the operation of the heating, ventilation and air conditioning system that are in electronic communication with the controller, at least one input device that is in electronic communication with the controller, wherein the at least one input device is able to modify variables utilized by the controller to improve performance of the heating, ventilation and air conditioning system; and at least one output device that is in electronic communication with the controller. The variables can include non-safety timing values and text-based information. The system may include counters that can be read-only, reset to zero and overwritten through the plurality of input devices. Historical data can be recorded, reviewed and selectively analyzed. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method for yarn piecing in a fasciated yarn spinning unit.
2. Description of the Prior Art
Significant improvements have been made in fasciated yarn spinning recently, resulting in high processing speeds of as much as 150 m/min.
In fasciated yarn spinning, a fiber bundle is twisted by a vortex while passing through a channel of an air nozzle. In the structure of the yarn thus obtained, a plurality of surface fibers are entangled around a core portion having substantially no twist.
Due to the above-mentioned double structure of the yarn, however, there is a serious problem with yarn piecing. The tensile strength of the fasciated yarn mainly depends on the binding effect of the surface fibers around the core portion. Accordingly, it is impossible to piece a yarn merely by overlapping the broken end with the fiber bundle as is the case of ring spinning. The broken end of the yarn has to be intermingled with the fiber bundle and twisted together for ensuring complete piecing.
Japanese Unexamined Patent Publication No. 53-35033 discloses a yarn piecing method for a fasciated yarn spinning unit comprising the steps of introducing a broken end of a yarn reversely into an air nozzle for twisting a fiber bundle, nipping the end between a pair of front rollers of drafting means disposed adjacent to the air nozzle, starting the drafting means to advance a fiber bundle, and simultaneously applying compressed air to the air nozzle to generate a vortex therein, whereby the broken end of the yarn and the fiber bundle are pieced together during passage through the air nozzle.
In this prior art, however, the broken end and the fiber bundle cannot be fully intermingled, which causes failure of piecing or a weak and/or conspicuous joint in the resultant yarn.
SUMMARY OF THE INVENTION
Thus, it is an object of the present invention to provide a method for yarn piecing in fasciated yarn spinning which can eliminate the above drawbacks in the prior art.
It is another object of the present invention to provide a yarn piecing method for fasciated yarn spinning which can easily be carried out by an automatic yarn piecer.
The above-mentioned objects are achievable, in a fasciated yarn spinning unit comprising a drafting means having a front pair of top and bottom rollers, a middle pair of top and bottom aprons, and a back pair of top and bottom rollers; an air nozzle; and a yarn detecter, whereby a fiber bundle attenuated by the drafting means is false-twisted to be a yarn by a vortex generated in the air nozzle and is wound to form a package under watching for yarn breakage by the yarn detecter, by a method comprising the steps of: stopping rotation of the back bottom roller in accordance with a yarn breakage signal from the yarn detecter while allowing the middle and front pairs to continue to rotate; introducing the yarn rewound from the package into the air nozzle from an outlet thereof to an inlet thereof; nipping the yarn between the middle pair; restarting generation of the vortex; and restarting the back pair with such a time delay after the preceeding nipping step that a leading end of the fiber bundle can overlap with a trailing end of the yarn within a nipping zone of the middle pair.
Preferably, prior to the nipping step of the middle pair, the top roller and top apron of the front and middle pairs are separated from the bottom roller and bottom apron thereof, respectively, to form a gap therebetween, and the yarn is guided through the gap to extend outside of the drafting means.
Further, the yarn may be cut to have a predetermined trailing length to ensure a proper overlapping of the yarn and the fiber bundle.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the present invention will now be described in detail in reference to the accompanying drawings, in which:
FIG. 1 is a schematic side view of a fasciated yarn spinning unit to which the present invention is applied;
FIG. 2 is a sectional side view of an air nozzle of the fasciated yarn spinning unit;
FIG. 3 is an enlarged sectional side view of a part of a drafting means mainly illustrating a means for individually pressing top side elements of the drafting means;
FIG. 4 is a perspective view of a driving mechanism for a drafting means;
FIG. 5 is a schematic side view of a fasciated yarn spinning unit just before a yarn piecing operation is commenced;
FIG. 6 is a perspective view of part of a suction tube;
FIG. 7 is a perspective view showing the motion of the suction tube relative to the drafting means;
FIGS. 8, 9, and 11 are views similar to FIG. 5 showing steps of yarn piecing according to the present invention; and
FIG. 10 is a perspective view of a guide plate.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A fasciated yarn spinning unit to which the present invention is applied is schematically illustrated in FIG. 1. The unit comprises a drafting means 2, an air nozzle 3, a pair of draw-off rollers 4, 4', a take-up roller 5, and an arm 10 for supporting a bobbin for a yarn package P, all of which are arranged on a machine frame 1. The drafting means 2 comprises three pairs of top and bottom elements, i.e., front rollers 6, 6', middle aprons 7, 7', and back rollers 8, 8'. As shown in FIG. 2, the air nozzle 3 has a channel 30 utilized for yarn passage and a plurality of jets 31 for ejecting compressed air within the channel 30 to generate a vortex.
A sliver A is fed from a can 20 on a floor to the drafting means 2 and is attenuated thereby to be a ribbon shaped fiber bundle of required thickness. The fiber bundle is then delivered from the front rollers 6, 6' into the air nozzle 3, in which it is twisted by the vortex and is transformed to a fasciated yarn B. The yarn B is continuously drawn out from the air nozzle by the draw-off rollers 4, 4' under the watch of a yarn detector 27 and then is wound on the bobbin to form the yarn package P by the action of the take-up roller 5 and the arm 10. For facilitating smooth running of the fiber bundle in the drafting means 2, a plate 9 may be provided between the back rollers 8, 8' and the middle aprons 7, 7'.
The drafting means 2 is devised in such a manner that the top side elements 6, 7, and 8 of the three pairs can individually be pressed onto or separated from the bottom side elements 6', 7', and 8' by means of air cylinders 41a, 41b,--secured on a back side surface of a weighting arm 40, as shown in FIG. 3. In FIG. 3, only the front pair 6, 6' and the middle pair 7, 7' of the drafting means 2 are illustrated for simplicity. The back pair 8, 8' may also be provided with a similar mechanism. The front top roller 6 is rotatably supported by a holder 45 secured to a piston rod 44 of the air cylinder 41a. The air cylinder 41a is provided with two air pipes 42 and 43 connected to a compressed air source through solenoid valves (not shown). When air is fed through the pipe 42 from the source, a piston 47 of the air cylinder 41 moves downward to press the top roller 6 onto the bottom roller 6', as shown by chain lines, so that nipping of the fiber bundle can be achieved.
On the other hand, when air is fed through the pipe 43, the piston 47 moves upward to form a gap H between the top and bottom rollers 6 and 6', as shown by solid lines. The same is true for the middle pair 7, 7' and the back pair 8, 8'.
As shown in FIG. 4, the bottom side elements 6', 7', and 8' are respectively connected to independent driving shafts 51, 52, and 53 through transmissions 54, 55, and 56. The transmissions 54, 55, and 56 include magnetic clutches MC 1 , MC 2 , and MC 3 , respectively, to engage or disengage the bottom side elements 6', 7', and 8' to or from the driving shafts 51, 52, and 53.
The yarn piecing operation is preferably carried out by an automatic yarn piecer traveling along a row of the spinning units on the frame. As partially illustrating in FIGS. 8, 9, and 10, the piecer comprises a rewinding roller 24 which holds the package P at a position apart from a surface of the take-up roller 5 and makes it rotate independently from the take-up roller 5 normally or reversely with various speeds during the piecing operation, a yarn catcher 26 for picking up a broken end of the yarn from the package surface and transporting it to an outlet 3b of the air nozzle 3, and an L-shaped suction tube 25 for receiving the end from the yarn catcher 26 and disposing it along a predetermined passage between the top and bottom side elements of the drafting means, as stated later.
The operations of the piecer are as follows: when the yarn detector 27 detects yarn breakage, it emits a yarn breakage signal to the magnetic clutch MC 3 , corresponding to the back bottom roller 8', which then stops the rotation of the back rollers 8, 8'. The middle pair 7, 7' and the front pair 6, 6' continue to rotate as usual. Thereby, the fiber bundle is forcibly broken between the back pair 8, 8' and the middle 7, 7' and the front portion thereof is discharged out from the drafting means through the front pair 6, 6'. The fiber bundle stops being fed and its leading end is kept between the back pair 8, 8' and the middle pair 7, 7', as shown in FIG. 5.
The yarn detector 27 also transmits a signal to the yarn piecer, which thereupon comes in front of the spinning unit in problem to commence the piecing operation. First, the air cylinders corresponding to the front top roller 6 and the middle top apron 7 are operated to release them from the corresponding bottom side elements 6' and 7'. As a result, the top side elements 6, 7 are maintained above the bottom side elements 6', 7' with the gap H therebetween. In this case, the bottom side elements 6' 7' continue to rotate.
As shown in FIG. 6, the suction tube 25 comprises a lateral portion 25a and a vertical portion 25b. The lateral portion 25a has a suction opening 25c on the side wall near the tip end thereof. The vertical portion 25b is connected to a suction source (not shown). In the non-operative position, the suction tube 25 is disposed above the drafting means 2 with the lateral portion 25a parallel to the axis of each element of the drafting means 2 and with the vertical portion 25b at one side of the drafting means. After the top side elements 6, 7 are released, the suction tube 25 moves downward to insert the lateral portion 25a into the gap between the top side elements 6, 7 and the bottom side elements 6', 7' so that the suction opening 25c confronts the inlet opening 3a of the air nozzle 3. FIG. 7 illustrates this state, in which the top side elements are omitted so as to clearly show the suction tube 25.
Next, the rewinding roller 24 is operated to slowly rotate the yarn package P reversely. At the same time, the yarn catcher 26 searches and picks up for the trailing end of the broken yarn on the package surface, as depicted by chain lines in FIG. 8. Then, the yarn catcher 26 moves toward the outlet 3b in synchronization with the rewinding operation of the rewinding roller 24, while holding the trailing end thereon.
Prior to arrival of the trailing end, the suction tube 25 starts the sucking operation. A suction stream is generated from the outlet 3b of the air nozzle 3 to the suction tube 25 through the channel 30 of the air nozzle 3. Accordingly, when the trailing end of the yarn is released from the yarn catcher 26, it is sucked into the channel 30 and then is sucked into the suction tube 25.
Then, the suction nozzle 25 moves backward along the drafting means 2. The lateral portion 25a passes through the gap H between the top side elements 6, 7 and the bottom side elements 6', 7' and then separates from the drafting means 2 through a space behind the middle pair 7, 7'. The rewinding operation of the rewinding roller 24 ceases at this moment. The yarn held by the suction tube 25 lies on a predetermined yarn passage between the top and bottom elements of the front rollers 6, 6' and the middle aprons 7, 7' and extends outside of the drafting means 2 through the space between the back top roller 8 and the middle top apron 7, as shown in FIG. 9. A guide plate 11 fixedly disposed behind the middle top apron 7 facilitates positioning of the yarn in line with the center axis of the drafting means 2 due to its structure, as shown in FIG. 10, which comprises left and right wings 11b slanted to constitute a concave center portion 11a. The yarn is naturally guided to the center portion 11a due to its own tension and lies on the predetermined yarn passage.
Thereafter, the magnetic clutch MC3 for the back bottom roller 8' is operated to rotate the back pair 8, 8', whereupon the fiber bundle begins to run forward again. Then, the air cylinder 41b for the middle top apron 7 is operated to press it onto the middle bottom apron 7' after a predetermined time delay T described hereunder. Thus, the yarn is nipped by the middle aprons 7,7'. At the same time, a cutter 28 provided in the vicinity of the suction opening 25c is operated to severe the yarn to provide a trailing end having a predetermined length L.
On the other hand, the rewinding roller 24 starts to drive the yarn package P with a speed corresponding to that of the middle pair, and the compressed air is supplied in the air nozzle 3 to generate the vortex. Thus the yarn extending from the package P runs forward while being nipped by the top and bottom aprons 7, 7' in such a manner that the trailing end of the yarn is overlapped with the leading end of the fiber bundle along a predetermined length stated later. In the air nozzle 3, the ends are entangled with each other by the vortex (FIG. 11).
Next, the air cylinder associated with the front top roller 6 is operated to press the front top roller 6 onto the front bottom roller 6'. Simultaneously, the yarn package P is released from the rewinding roller 24 and is disposed on the surface of the take-up roller 5.
Thus, the yarn piecing operation is completed, and normal yarn spinning is started again.
In the present invention, the timings for starting and stopping the associated parts of the spinning unit and the yarn piecer are very important. In particular, the relation of the length L of the yarn to be reserved to the delay time T should be decided taking the processing speed into account, so that the proper overlapping length of the yarn with the fiber bundle is obtained. According to the present inventors' experience, the overlapping length is preferably in a range from 10 to 30 mm to ensure a good strength as well as good appearance of the resultant yarn.
As stated above, according to the present invention, since the ends of the yarn and the fiber bundle to be pieced move together under soft pressure of the middle aprons, they tend to partially intermingle with each other during the passage and therefore can be completely united by the vortex applied thereafter. | A novel method for yarn piecing in a fasciated yarn spinning unit, in which a broken end of a yarn and the fiber bundle to be pieced together are nipped and intermingled with each other between a soft nipping area between middle top and bottom aprons and thereafter are false-twisted by a vortex in an air nozzle. Motions of the associated parts are controlled as so to be able to achieve a suitable overlapping length of the yarn and the fiber bundle in the nipping area of the aprons. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a control system of electrically memorizing the distance between a first and a second member which are in a relative distance variable relation with each other on a straight line, reading the memorized distance between the two members, when necessary, and reproducing the distance between the two members at any time; and to a control device for memorizing and reading the reproducing the position of a stool or a chair such as used with dentists, physicians, barbers, beauty specialists and the like.
2. Prior Art
Heretofore, this kind of control system of or device for reading and reproducing the memory which has been used is of the system or device in which a position detection device including a potentiometer is brought into interlocking with a material to be controlled in response to the position of the material, the position of the material is read in terms of a resistance value of the potentiometer and thereafter the resistance value is memorized as a resistance value by another motor-interlocking potentiometer provided through a contact relay (for example, Japanese patent publication No. 151291/1977). But according to this system, it is not only inevitable to provide a mechanically interlocking mechanism between a position detection potentiometer and a material to be controlled and difficult to mount a position detection device but also the potentiometer is in an interlocking relation with the material to controlled, and accordingly, when the material is moved, the resistor and a slider cause wear by slide contact between them irrespective of manual or automatic operation, with the result that the resistance value detected is reduced in relability and in addition thereto, the mechanical error of the interlocking mechanism in combination with the reduced reliability further reduce reliability. To eradicate this vicious cycle, it is necessary to use the position detection potentiometer in a non-heating area and this in turn makes it necessary to use a highly reliable and expensive potentiometer. This interlocking mechanism must also be accurate, which in turn added to production cost. This is a disadvantage. Also, when the memorized position of the material is reproduced and controlled by comparing the resistance value of the motor interlocking potentiometer with that of the position detection potentiometer provided through the contact of a relay or the like. Accordingly, in the above-described control system of memorizing, reading and reproducing, a position of a material to be controlled, a control circuit for position detection and memory, position reading, etc. is of complicated structure including a relay and the like, and wear of the contact of the relay reduces the reliability of reproducibility in the system. This is another disadvantage. This invention has been accomplished to obviate the disadvantages of the conventional control system of memorizing, reading and producing a position of a material to be controlled and has a very wide range of application.
SUMMARY OF THE INVENTION
The system of the invention provides a system of transmitting the ultrasonic pulse between the first and the second member which are in a relative distance variable relation with each other on a straight line, detecting the distance between the members in terms of the time constant of another set pulse on the basis of the propagation time detected, reading the memorized distance as occasion demands and reproducing and controlling the members at any time to the memorized distance.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the principle diagram of the control system of memory, reading and reproduction according to the invention system;
FIG. 2 shows the principle diagram of another embodiment of the invention system;
FIG. 3 shows a block diagram for practicing the control system of memory and reproducing according to the invention;
FIG. 4 is an electric circuit corresponding to FIG. 3;
FIGS. 5, 6, 7 and 8 are time charts respectively of FIG. 4;
FIG. 9 is a front view of one embodiment of a dental treatment chair including the device of the invention; and
FIG. 10 is a plan view of the embodiment of FIG. 9.
DETAILED DESCRIPTION OF THE INVENTION
A description will now be given of a basic principle of this invention system. FIG. 1 shows one aspect of the basic principle of this invention system, according to which an ultrasonic transmitter SO and an ultrasonic receiver RO (hereinafter referred to as a transmitter SO and receiver RO) respectively for transmitting and receiving an ultrasonic pulse are attached to a second member R whose movement is controlled within the straight area of control in which a maximum separation distance Lmax from a first member S is determined, and control of the distance in the straight area of control is made by transmission and reception of an ultrasonic pulse respectively by the transmitter SO and the receiver RO. According to this system, the distance LN between the first member S and the second member R is detected in terms of propagation time of the ultrasonic pulse transmitter between the transmitter SO and the receiver RO attached to the first member and the second member. Accordingly, supposing in FIG. 1 that an ultrasonic pulse is periodically and intermittently sent forth from the transmitter SO and that the pulse set forth is received by the receiver RO attached to the second member R which is disposed in an opposed relation with the transmitter SO (hereinafter referred to as a received pulse), it will readily be conceivable that the distance LN between the first member S and the second member R can be detected by grasping the period of time during which the ultrasonic pulse propagate through the distance LN between the transmitter SO and receiver RO. Accordingly, a memory set pulse lagging in time and different from the above received pulse is generated in synchronism with the time of sending forth of the ultrasonic pulse from the transmitter SO, and the distance LN between the first member S and the second member R can be grasped in terms of the time in which the memory set pulse lags behind the time when the ultrasonic pulse was sent forth (hereinafter referred to as time constant of memory set pulse). According to the system of the invention, the oscillation period of the ultrasonic pulse is fixed at a time longer than the time necessary for the ultrasonic pulse to propagate through a maximum separation distance between the first member S and the second member R. The reason is that each time the ultrasonic pulse which the transmitter SO periodically and intermittently sends forth is received by the receiver RO, a time difference between the time when the ultrasonic pulse is given forth by the transmitter SO and the time when it is received by the receiver RO is successively compared with the time constant of memory set pulse, and the time constant of set pulse is changed accordingly until the time difference and the time constant are brought into agreement, and when they both are in agreement, the distance LN between the first member S and the second member R is converted into the time constant of memory set pulse and memorized. Also, the principle of reading and reproduction and control according to the system of the invention is to read that distance LN between the members S and R which was converted into the time constant of memory set pulse and was fixedly memorized through the memory set pulse generated in response to the ultrasonic pulse periodically and intermittently sent forth by the transmitter SO and simultaneously, to read the distance LN' between the two members S and R through the received pulse, to move the distance LN' between the members S and R until the received pulse and the memory set pulse are in agreement and to reproduce and control the distance.
In FIG. 1, the transmitter SO and the receiver RO are shown directly disposed between the first member S and the second member R, while in the principle diagram illustrating another embodiment shown in FIG. 2, the transmitter and the receiver are shown indirectly disposed between the first member S and the second member R. Namely, in the movement elevatable by a pantagraph mechanism P in FIG. 2 when it is desired to control height H, it is only necessary to oppose the transmitter and receiver in an opposed relation on a straight line in the dotted line position. But if it is difficult to position the transmitter and receiver in the relation described above for some reason or other, it is possible to control the height H in terms of the distance between the transmitter and receiver by disposing the transmitter SO in an opposed relation with the receiver RO on a horizontal line between elevatably expansible links P 3 , P 5 and P 4 , P 6 , as shown in FIG. 2. The principle of reproduction and control of distance in the embodiment illustrated is to memorize the distance between the first and second members and to read and reproduce and control the memorized distance at any time in the same manner as described with reference to FIG. 1. Also, the ultrasonic transmitter and receiver used in this invention are described in detail in the United States patent application Ser. No. 165,385 filed in July 3, 1980 by the present applicant and hence only the gist of the application is described below to avoid repetition.
(a) The ultrasonic transmitter is least affected by noise because the transmitter sends forth an ultrasonic pulse small in angle of direction.
(b) Standing waves are least likely to occur because the transmitter sends forth an ultrasonic pulse corresponding to an ultrasonic driving pulse and excellent in damping characteristic.
(c) Because a piezoelectric element high in mechanical Q is used in the receiver having the same structure as the transmitter, the receiver is insensitive to a frequency other than a limited frequency and is hard of sensing trembling air, vibration from fitting surfaces, or natural convection and the like in the form of external noise.
Since it will have been fully understood from the above description how the basic principle of the invention system works, a detailed description will now be given of the memorizing principle of and the reading and reproducing principle of the invention system with reference to a preferred embodiment of the invention. FIG. 3 is a block diagram for practicing the invention; FIG. 4 is an electric circuit diagram according to the block diagram of FIG. 3, and FIGS. 5 through 8 are time charts corresponding to FIG. 4. In FIG. 3, the electric circuitry for practicing the invention comprises an ultrasonic pulse generation unit I, a received pulse generation unit II, a control command circuit unit III, a memory set pulse generation unit IV, a comparison circuit V, a drive circuit unit VI, and a memory set pulse control unit VII. Referring schematically to the operating principle of these circuits, the ultrasonic pulse generation unit I makes switching control of an ultrasonic pulse drive circuit 11 by a trigger pulse in FIG. 5a generated from a synchronous trigger pulse generation circuit 12, excited the circuit 11, generates a driving pulse as shown in FIG. 5b and applies the driving pulse to a transmitter SO to thereby send forth an ultrasonic pulse from the transmitter. The ultrasonic pulse sent forth in the manner described above is received by the receiver RO inside the received pulse generation unit II. The ultrasonic pulse received by the receiver RO is amplified, detected and shaped in waveform by an ultrasonic received pulse amplification detection circuit 21 and waveform shaping circuit 22, and inputted into a latch circuit 51 inside the comparison circuit unit V in the form of a received pulse. The control command circuit unit III generates a command signal as shown in FIG. 5e from a memory command signal generation circuit 313 by operation of a memory command switch 31 and at the same time brings the output Q of R--S F/F 311 up to an H-level to thereby bring an analog switch into a low resistance state in which a motor interlocking potentiometer 411 is supplied with supply power VDD. Also, a command signal as shown in FIG. 7f is generated from a reading command circuit 323 by operating a reading command switch 32 and at the same time the output Q is brought up to an H-level to thereby bring an analog switch 322 into a low resistance state in wh which the motor interlocking potentiometer 411 is supplied with supply power VDD. According to the embodiment, R--S F/F 311, 321 and analog switches 312 and 322 are constructed not to operate at the same time, but the memory set pulse generation unit IV, when a trigger pulse (FIG. 5a) is inputted thereinto, is constructed to generate a memory set pulse shown in FIG. 5d lagging behind the time of generation of the trigger pulse by the time constant which the motor interlocking potentiometer 411 and an external capacitor 412 determine. Also, if memory set means each consisting of an analog switch (not shown) connected in series to a motor driven potentiometer or manually operated memory set potentiometer (not shown) are independently constructed, a plurality of memory set pulses or manual set pulses are generated to make it possible to memorize a plurality of materials to be controlled. When a plurality of potentiometers are provided, it is apparent that kinds of control proportional to the number of potentiometers are possible. The comparison circuit unit V in the embodiment shown comprises an agreement circuit 54 constructed of a latch circuit 51, a rise-up differential pulse generation circuit 52, a distance decision circuit 53 and a two-input NAND gate, and is constructed to successively input thereinto the received pulse received and detected by receiver RO and the memory set pulse (which indicates a pre-memorized distance) generated by a memory set pulse generation unit IV and shown in FIG. 5d and to detect the order in which they are inputted into the comparison circuit and send forth a control signal to a drive circuit unit VI. A latch circuit 51 inputs the H-level output thereof into a J-input terminal of a distance decision circuit 53 consisting of a rise-up differential pulse generation circuit 52 and J-K F/F by the received pulse being inputted into the latch circuit 51 and inputs the L-level output thereof into a K-input terminal of the distance decision circuit 53 and reverses the output of the latch circuit as shown in FIGS. 5g and each time a trigger pulse (FIG. 5a) is inputted into the latch circuit. Accordingly, even if noise enters the receiver RO after the received pulse was inputted into the latch circuit 51, the output of the receiver RO maintains the latched state and protects the receiver against abnormal function due to the noise. The rise-up differential pulse generation circuit 52 generates an agreement detection pulse indicated in FIG. 5c and having the same width as a memory set pulse (FIG. 5d) in time of the rise-up of the H-level output of the latch circuit 51. The distance decision circuit 53 consists of J-K F/F, and inputs the output of the latch circuit 51 into a J-input terminal and a K-input terminal and also inputs a memory set pulse (FIG. 5d) into a CK-input terminal. The agreement circuit 54 consists of a two-input NAND gate for inputting the memory set pulse and the agreement detection pulse into the circuit 54, and the circuit 54, when the memory set pulse and agreement detection pulse are simultaneously inputter thereinto, inputs an L-level output shown in FIG. 5k into the R-input terminals of the respective R-S latch circuits 61, and 71 of a drive circuit unit VI and a memory set pulse control unit VII. The drive circuit unit VI consists of and R-S latch circuit 61, a distance signal generation circuit 62, and a distance drive circuit 63. The R-S latch circuit 61 is constructed in such a manner than when the circuits shown in FIG. 4 start operation, namely when the circuits shown are supplied with supply power VDD, the circuit is initially reset and the output of the circuit 61 is fixed to the L-level. The distance signal generation circuit 62 is constructed in such a manner that when a reading command switch 32 is not operated, or when the distance between the transmitter SO and the receiver RO are brought into agreement with a pre-memorized distance and the memory set pulse and the agreement detection pulse are inputted simultaneously into the agreement circuit 54, the distance signal generation circuit 62 does not permit the passage of Q and Q outputs of the distance decision circuit 53 therethrough but brings driving outputs l, m down to an L-level, and that only when a reading command switch 32 is operated, the circuit 62 inputs the Q and Q outputs of the distance decision circuit 53 into a distance drive circuit 63. The memory set pulse control circuit VII comprises an R-S latch circuit 61, a positive-negative rotation signal generation circuit 72 and a servomotor drive circuit 73. The R-S latch circuit 71 and the positive-negative rotation signal generation circuit 72 function respectively in the same manner as the R-S latch circuit 61 and the distance signal generation circuit 62. A further description of the circuits 71 and 72 are omitted to avoid duplication. The servomotor drive circuit 73 is constructed in such a manner that it receives a signal from the positive-negative rotation generation circuit 72 by operation of a memory command switch 31, rotates a servomotor 74 until a time difference between the memory set pulse and the agreement detection pulse is reduced to zero, changes the resistance value of a motor interlocking potentiometer 411 disposed in an interlocking relation with the servomotor and thereby converts the distance between the transmitter and the receiver into a transmission period of a set pulse of the set pulse generation unit IV (the time constant of the monomultivibrator) and memorizes and maintains the distance between transmitter SO and the receiver RO.
A description will now be given of how the circuits constructed as above operate by an input signal from outside and makes intended memorizing, reading and reproduction control. First, for convenience of explanation of memory operation, a description is given of the case wherein a memory set pulse is generated earlier memorized distance between the transmitter SO and the receiver RO is shorter than a distance to be afresh memorized between the two. (Refer to FIG. 5 for a chart). In this case a memory set pulse d is generated and at the same time a memory command signal e is generated from a memory command signal generation circuit 313 by operating a memory command switch 31. The memory command signal e brings the output of the R-S latch circuit 71 up to an H-level and brings Q and Q outputs of distance decision circuits 53 into a state of the outputs capable of being inputted into a servomotor drive circuit 73. The distance decision circuit 53 inputs the outputs g, h of latch circuit 51 thereinto and sends forth the Q and Q outputs of the distance decision circuit 53 at the time of rise-up of the memory set pulse. At this time, if there is no change in the state of outputs g and h of latch circuit 51 at the time of rise-up of the memory set pulse, the Q and Q outputs the distance decision circuit 53 hold the same state. Accordingly, the Q and Q outputs of distance circuit 53 pass through a positive-negative rotation signal generation circuit 72 and inputs the output shown in FIGS. 5i and 5j into a servomotor drive circuit 73. By the positive-negative rotation signals i and j the servomotor drive circuit 73 rotates a servomotor 74 in the direction of increasing the resistance value of motor interlocking potentiometer 411 and increases the time constant of set pulse d (a transmitting period of set pulse) until the memory set pulse d and agreement detection pulse c are brought into agreement. If the memory set pulse d and agreement detection pulse c are brought into agreement by this operation, an agreement pulse designated by FIG. 5k is generated from an agreement circuit 54. The agreement pulse K reverses the output of R-S latch circuit 71 to an L-level and fixes the outputs i and j of positive-negative rotation signal generation circuit 72 to the L-level and thereby stops the rotation of servomotor and completes memory operation. In this memory operation, when the memory set pulse lags in generation behind the agreement detection pulse, namely when the earlier memorized distance between the transmitter SO and receiver RO is longer than the distance to be afresh memorized, it will readily be conceived that memorized distance between the transmitter SO and receiver RO is longer than the distance to be afresh memorized, it will readily be conceived that memorizing operation is effected by rotating the servomotor in the direction of reducing the resistance value of motor interlocking potentiometer 411 on the same principle as described above. The detail of the operating principle in this case is shown in a time chart in FIG. 6. It will be understood that the distance between the first member S and the second member R is memorized in terms of the time constant of memory set pulse, namely, in terms of the resistance value of motor interlocking potentiometer 411.
A description will now be given of the reading and reproducing and control principle. For simplicity's sake, a description is given of the case wherein the earlier memorized distance between the transmitter SO and the receiver RO (Refer to FIG. 7 for a time chart). In this case, by operating a reading command signal f is generated from a reading command signal generation circuit 323. The reading command signal f bring the output of R-S latch circuit 61 up to an H-level and brings the Q and Q outputs of distance decision circuit 53 into a state of the outputs capable of being inputted into the distance drive circuit 63. Accordingly, the Q and Q outputs of the distance decision circuit 53 pass through the distance signal generation circuit 62 and input the outputs shown in FIGS. 7l and m into the distance drive circuit 63. By the distance signals shown in l and m the distance drive circuit 63 generates driving output for reducing the distance between the transmitter SO and the receiver RO until the memory set pulse d and the agreement detection pulse e are brought into agreement, an agreement pulse shown by FIG. 7k is generated from an agreement circuit 54. The agreement pulse K reverses the output of R-S latch circuit 61 to an L-level and brings the outputs of two NAND gates of distance signal generation circuit 62 to the H-level, and consequently driving is stopped by fixing the outputs l and m to the L-level to thereby complete reading and reproducing operation. In this reading operation, when the pre-memorized distance between the transmitter SO and receiver RO is longer than the present distance between the transmitter and receiver, it will readily be conceived that a driving force to increase the distance between the transmitter and receiver is produced on the same principle as described and reading and reproducing operation is effected. Reference to the time chart in FIG. 8 for the detail of the operating principle in this case will make it clear that the distance between the first member S and the second member R is reproduced and controlled to the pre-memorized distance.
It should be understood that, instead of the motor interlocking potentiometer 411 of the memory set pulse generating unit IV, the memory system of the invention makes it possible to control the capacity of capacitor 412 by bringing the capacitor 412 into interlocking relation with the servomotor.
From the description given above, the control system of memorizing and reading and reproducing a material to be controlled will have fully been understood. The invention system provides characteristic advantages in that the system enables reading and reproduction in entirely contactless manner without including any mechanically contacting member in the control circuit, that because an ultrasonic pulse very slow in transmission rate is used as a medium for measuring distance, highly accurate measurement is possible and consequently can be widely used in the control of distance between the first and second members which can make not only relatively linear movement but also whose movement can be converted into linear movement, that the relative position between two members can successively be controlled to a desired position, that, because a resistance value for determining the time constant of a memory set pulse is used as a medium for memorizing distance, breaking the supply power for control circuit can still hold memory contents, and that change by effect of years is small.
Next, in a stool or a chair in which the control device for preproduction utilizing the control system of memory and reading and reproduction is utilized in a dental and other medical treatment chairs, barber's or beauty specialist's chair, a description will now be given of a device for automatically and electrically controlling elevation and tilting of a first member (for example, base) and a second member (for example, a seat, backrest, headrest, etc.), which are in an opposed distance varying relation by their relative linear movement, by use of an ultrasonic pulse as a position detecting medium, with reference to a dental treatment chair. FIGS. 9 and 10 are a front view and a plan view, broken in part, showing one embodiment of a dental treatment chair including the device of the invention. Referring to the known structure of the treatment chair shown and to the problems thereof, a treatment chair 81 includes a base 83 resting on the floor 82, a seat 85 adapted to be elevated while being maintained substantially horizontally by a cylinder shaft 84 of a hydraulic elevation mechanism (not shown) incorporated into the base 83, a backrest 89 capable of tilting back and forth around a rotating shaft 88 with respect to the chair 85 by expansion and contraction of a cylinder shaft 87 of a hydraulic tilting mechanism 86, and a headrest 91 capable of similarly tilting back and forth with respect to the backrest 89 through an arm 90. Elevation of the seat 85 and tilting of the backrest 89 are artificially carried out by operation of an elevation pedal 920 and a tilting pedal 921 of a foot pedalling device 92 disposed in the floor 82. Stated differently, the seat 85 becomes a second member which can change its opposed distance through linear movement (elevational movement) with respect to the base 83 which is a first member, while tilting of the backrest 89 with respect to the seat 85 is substituted by linear expansion and contraction movement of a cylinder shaft 87 of the hydraulic tilting mechanism 86. In this case, when a fixed portion 870 of the hydraulic tilting mechanism 86 is used as a first member, the cylinder shaft 87 becomes a second member which changes its opposed position with respect to the first member by linear movement so as to artificially control the distance between the first and second members. By the way, when a multiplicity of patients are treated successively, it becomes a great burden of labor to a doctor or his assistant for him to decide a chair position agreeable to various positions fit for treatment in consideration of a bodily difference between individuals by the foot pedalling operation alone. Thus, in the invention, the desired positioning of a chair is effected by foot pedalling operation, and the position of the chair is memorized by single operation of a memory command switch and the position of the chair is reproduced and controlled to the desired position by operation of a read command switch as occasion demands.
Referring now in detail to the device of the invention, the reference character SO in FIGS. 9 and 10 designates an ultrasonic pulse transmitter mounted on the underside of a chair 85 and RO designates an ultrasonic pulse receiver fixed to a base 83 in an opposed relation with the transmitter SO on a straight line preferably with the respective principal axes brought substantially into agreement with each other. These transmitter SO and receiver RO are intended to control the position of the seat 85. Similarly, the characters SO' and RO' designate respectively an ultrasonic pulse transmitter and an ultrasonic pulse receiver for use in the control of tilting position of a backrest 89 and are disposed in the same opposed relation with a stationary portion 870 and a cylinder shaft 87 of the hydraulic tilting mechanism 86. The numeral 94 designates a control box having its main body portion incorporated into the backrest 89 as shown in FIG. 10. In the box 94 are contained both for elevation of seat and for tilting of backrest an ultrasonic pulse generation unit I (except transmitter SO) and a received pulse generation unit II (except receiver RO) described in detail in conjunction with the previously described control system of memory and reading and production, a control command circuit unit III (except a memory command switch 31 and a read command switch 32), a memory set pulse generation unit IV, a comparison circuit unit V, a drive circuit unit VI, and a memory set pulse control unit VII. The numeral 93 designates a command switch box which has its main body portion incorporated into the backrest 89 in the same manner as the box 94; 31 a memory command switch; and 32 designates a read command switch. These switches are constructed to give command signals simultaneously to the control command circuit III for seat elevation and for backrest tilting. For elevation of seat 85 and tilting of backrest 89 is used as stated a hydraulic mechanism as a direct operating instrument and control of the mechanism is made by operating a foot pedalling device 92 and the read command switch 32. The output terminal for foot pedalling and the output terminal for automatic control by command switch are connected in series. It is to be understood that control can be made by use of any of the systems. How the dental treatment chair constructed as above is operated by a signal from outside and the intended memory, reading and reproduction is effected is described in detail in the above control system of memory, reading and reproduction, and hence a further description of the same is omitted. And how to use the dental chair will briefly be described. First, the positions of chair 85 and backrest 89 are set to desired positions by operating elevation pedal 920 and tilting pedal 921 of foot pedalling device 92. When it is desired to memorize the positions, it is only necessary to operate a memory command switch 31. The distance between the transmitter SO' and the receiver RO' are fixedly memorized in terms of the time constant of memory set pulse for elevation and tilting purposes, namely in terms of a resistance value of a motor interlocking potentiometer on the described operating principle. When it is desired to reproduce the respective positions of seat 85 and backrest 89 memorized by the above operation as occasion demands, all that is necessary to do is to operate a read command switch 32. Reading and reproduction is carried out on the described operating principle by thus operating the read command switch 32. The once memorized contents are not charged as long as the memory command switch 31 is not re-operated even if the positions of seat 85 and backrest 89 are changed.
The description above has been given of the device of the invention with reference to the dental treatment chair illustrated by way of example, but the invention can find application to various other scopes of use without being limited to the embodiment shown. For example, installation of the transmitter and receiver in an opposed relation at relatively short distances from each other at suitable portions of a medical treatment table (including an operating table) in addition to the dental chair, barber's chair beauty specialist's chair, and other conveying and elevation devices (to be referred to hereinafter as "treatment chair or stool") provides advantageous application of the invention to position control of the moving elements of the treatment chair and stool. Also, in conjunction with the structure of the above embodiment, any optional change may be introduced in relative relation and position of the transmitter with the receiver and in the set positions of the command switches, control boxes, etc.
As described, the invention provides immense advantages such as that automatic control is possible without any mechanically contacting member contained in the control device but in an entirely contactless manner, that very accurate measurement is possible at a relatively short distance because an ultrasonic pulse far slower in transmission rate than an electric signal and relatively small in pulse width and small in directivity is used as a medium for measurement and control of position; that the invention is widely applicable to control of the distance between the first and second members not only when they are in a relatively linearly movable relation with each other, but also when their movement is convertible into linear movement; that position control is possible without introducing a change in the structure of the stools or chairs in conventional use; that a desired position is reproduced and controlled as occasion demands; that because a resistance value determining the time constant of memory set pulse is used in memorizing a desired distance, the control circuit still holds the contents of memory even if the supply power of the control circuit is broken; and that change effect of years is small. | This disclosure relates to a control device of transmitting an ultrasonic pulse from an ultrasonic transmitter to an ultrasonic receiver by disposing the transmitter and the receiver between two movable members which are placed in a variable relation in linear distance with each other, converting aerial propagation time of the pulse from the transmitter to the receiver into an electrical means, memorizing and holding a distance between the two members by the electrical means, and reading the memorized distance at any desired time and reproducing the distance. The disclosure also relates to a control device using the system. | 0 |
SUMMARY OF THE INVENTION
The solar heating panel provided by the invention has two spaced parallel elongated header tubes for the inlet and outlet of the heat exchange medium, the headers being interconnected by a network of longitudinal and transverse tubes of differing internal sizes arranged to produce an irregular flow pattern whereby a constant low pressure of the moving heat exchange medium results.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view of the panel, and
FIGS. 2, 3, 4, 5 and 6 are, respectively, cross sectional views taken on lines 2--2, 3--3, 4--4, 5--5 and 6--6 of FIG. 1.
DESCRIPTION OF THE INVENTION
The solar heating panel, or collector plate, provided by the invention comprises a sheet metal plate of desired size and configuration having formed therein a network or grid of closed interconnecting passages or tubes. The panel is preferably formed by the Roll-Bond process which is described and claimed in U.S. Pat. Nos. 2,690,002, 3,053,514, 3,463,676 and perhaps others. The method of manufacture of the panel forms no part of the present invention and will not be further described in this specification. It will be understood, however, that the solar panel as used in accordance with the invention is preferably formed of copper but may be formed of aluminum or other metal and has a black chrome coating.
The preferred embodiment of the invention disclosed in this specification comprises an elongated rectangular plate A having a network of closed conduits formed therein the configuration and internal sizes of which produce a constant low pressure flow of heat absorbing fluid medium resulting in a high efficiency which has been found to be in the range of 70% to 80%.
The preferred network of conduits comprises inlet and outlet headers 2, 4, respectively, which extend longitudinally of the panel at opposite sides thereof, both of which have the same internal oval cross sectional shape and size as shown in FIG. 2. Three additional longitudinally extending conduits 6, 8, 10 are positioned between and parallel to the headers 2, 4 and are co-extensive with the headers. Conduit 6 which is closely adjacent header 2 has the oval cross sectional shape shown in FIG. 5, while conduits 8 and 10 have the same internal size and oval cross sectional shape shown in FIG. 3, which is smaller than that of conduit 6. Cross conduits 12, 14 are provided at the opposite ends of the panel and connect the ends of the longitudinal conduits 4, 6, 8, 10. Header 2 is connected to conduit 6 at 16 and is therefore connected into this primary, rectangular grid.
The longitudinal conduits are interconnected by transverse conduits positioned internally of the primary rectangular grid, the arrangement and internal sizes of the transverse conduits being such that the network of conduits between the inlet end 20 of inlet conduit 2 and the outlet end 22 of the outlet conduit 4 produces the irregular flow pattern having the constant and low pressure resulting in the high efficiency which is characteristic of the panel.
The adjacent longitudinal conduits 6, 8 are connected by a tier of transverse conduits 30, there being fifteen in this tier in the disclosed panel which has an overall length of 74 inches. Each of the conduits 30 has an angular bend midway its length and has the oval cross sectional shape and relative size shown in FIG. 3. The adjacent longitudinal conduits 8, 10 are connected by a second tier of transverse conduits 40, these being sixteen of these in this tier in the disclosed panel. These conduits are so positioned that each extends angularly to the length of the panel at a preferred angle of approximately 55° to the adjacent longitudinal conduits 8, 10 and form a series of oppositely directed triangles having their apices alternately at conduits 8 and 10. The longitudinal conduit 10 and header 4 are connected by a third tier of transverse conduits 50, there being sixteen of these in this tier of the disclosed panel. These conduits are positioned so that each extends angularly to the length of the panel at a preferred angle of approximately 55° to the adjacent longitudinal conduits 4, 10 and form a series of oppositely directed triangles having their apices alternately at header 4 and conduit 10. Transverse conduits 40 and 50 have the same relatively small cross sectional size and oval shape which is illustrated in FIG. 4. | The disclosure is of a metal panel forming part of a solar heating system, having interconnected longitudinal and transverse passages through which the heat exchange fluid flows. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is related to and claims priority to U.S. Provisional Application No. 61/465,080, entitled “ROBOTIC WORK OBJECT CELL CALIBRATION SYSTEM AND METHOD,” (Trompeter), filed on Mar. 14, 2011, to U.S. Provisional Application No. 61/518,912, entitled “ROBOTIC WORK OBJECT CELL CALIBRATION SYSTEM AND METHOD,” (Trompeter), filed on May 13, 2011, to U.S. Ser. No. 13/385,091, entitled “ROBOTIC WORK OBJECT CELL CALIBRATION SYSTEM,” (Trompeter), filed on Feb. 1, 2012, to U.S. Ser. No. 13/385,797, entitled “ROBOTIC WORK OBJECT CELL CALIBRATION METHOD,” (Trompeter), filed on Mar. 7, 2012, to PCT Application No. PCT/US2013/00146, entitled “AUTOMATIC AND MANUAL ROBOT WORK FINDER CALIBRATION SYSTEMS AND METHODS”, (Trompeter) filed on Jun. 10, 2013, and is a continuation-in-part to U.S. Ser. No. 14/155,646, entitled “ROBOT CALIBRATION SYSTEMS”, (Trompeter), filed on Jan. 15, 2014.
FIELD OF USE
[0002] The present invention relates to a calibration system for use with an industrial robot.
BACKGROUND OF THE INVENTION
[0003] The value of industrial robots has historically been driven by the automotive industry. However, that value is now being realized in other industries, as robots are being designed for tasks as diverse as cleaning sewers, detecting bombs, and performing intricate surgery. The number of industrial robots sold globally in 2013 was nearly 180,000 units, essentially tripling the number of units sold in 2009, with the automotive, metal, and electronics industries driving the growth.
[0004] Prior approaches to calibrating industrial robots use measuring devices either determine the inaccuracies of the robots after the robot is built, or measure work piece positions relative to the robots' positions prior to off-line programming.
[0005] Some of the prior art includes:
[0006] U.S. Pat. No. 8,651,858 (Berckmans, et al.) discloses a method of creating a 3-D anatomic digital model for determining a desired location for placing at least one dental implant in a patient's mouth. One such method uses a calibration device that involves two intersecting lasers to place a dental implant into a cast model of a patient's mouth. The lasers are not mounted onto a fixture since the fixture-to-robot location is known. The method creates a 3-D anatomic digital model for determining a desired location for placing at least one dental implant in the mouth of a patient.
[0007] U.S. Pat. No. 7,979,159 (Fixell) discloses a method and a system for determining the relation between a local coordinate system located in the working range of an industrial robot and a robot coordinate system. The method includes attaching a first calibration object in a fixed relation to the robot and determining the position of the first calibration object in relation to the robot. Then, locating at least three second calibration objects in the working range of the robot, a reference position for each of the second calibration objects in the local coordinate system can be determined by moving the robot until the first calibration object is in mechanical contact with each second calibration object. By reading the position of the robot when the calibration objects are in mechanical contact the relation between the local coordinate system and the robot coordinate system can be calculated.
[0008] U.S. Pat. No. 7,945,349 (Svensson, et al.) discloses an invention which relates to a method and a system for facilitating calibration of a robot cell. One or more objects and an industrial robot perform work in connection to the objects, wherein the robot cell is programmed by means of an off-line programming tool including a graphical component for generating 2D or 3D graphics based on graphical models of the objects. The system comprises a computer unit located at the off-line programming site and configured to store a sequence of calibration points for each of the objects, and to generate a sequence of images including graphical representations of the objects to be calibrated and the calibration points in relation to the objects, and to transfer the images to the robot, and that the robot is configured to display the sequence of images to a robot operator during calibration of the robot cell so that for each calibration point a view including the present calibration point and the object to be calibrated are displayed for the robot operator.
[0009] U.S. Pat. No. 7,756,608 (Brogardh) discloses a method for calibrating an industrial robot including a plurality of movable links and a plurality of actuators effecting movement of the links and thereby the robot. The method includes mounting a measuring tip on or in the vicinity of the robot, moving the robot such that the measuring tip is in contact with a plurality of measuring points on the surface of at least one geometrical structure on or in the vicinity of the robot, reading and storing the positions of the actuators for each measuring point, and estimating a plurality of kinematic parameters for the robot based on a geometrical model of the geometrical structure, a kinematic model of the robot, and the stored positions of the actuators for the measuring points.
[0010] “Calibration of Robot Reference Frames for Enhanced Robot Positioning Accuracy, Robot Manipulators”, Frank Shaopeng Cheng (2008) (pages 95-112) discusses robot calibration using tool center points. The Cheng reference relates to industrial robot manipulators which are important components of most automated manufacturing systems. The reference does not mention lasers. While a “tool center point” is generally defined as the origin of the tool coordinate system, a “laser intersection point” is a point where two or more lasers intersect.
[0011] What is needed is a robot calibration system for use with industrial robots to improve cost and time factors in applications where absolutely accurate robots are not really necessary. Examples include body-in-white applications, resistance welding, material handling, and MIG welding.
[0012] The primary objective of the robot calibration system of the present invention is to provide a calibration system that is simpler to operate, results in improved precision, involves a lower investment cost, and entails lower operating costs in a manufacturing environment.
SUMMARY OF THE INVENTION
[0013] The robot calibration system of the present invention address these needs and objectives.
[0014] The calibration system comprises means for emitting a pair of lasers beams. The first preferred embodiment of the calibration system of the present invention requires that the lasers are mounted so that the laser beams intersect at a 90 degree angle. The second preferred embodiment of the calibration system of the present invention requires that the lasers are mounted so that the laser beams intersect at a range of angles from between 85 degrees and 95 degree relative to each other, at a laser intersection point. The laser intersection point defines the location of a robotic reference frame.
[0015] The geometry of the work object is preferably basic and the lasers are mounted in an L-shaped or F-shaped member. The angular positions of a robot tool are adjustable relative to the robotic reference frame.
[0016] The first preferred embodiment of the calibration system of the present invention, the work object includes two lasers positioned onto a work piece or tool, at a known location (a numerical control block or NAAMS mounting pattern) with the two laser beams intersecting at a 90 degree angle and continuing to project outward. A laser intersection point of the two laser beams defines the correct location of the robotic reference frame. To accomplish this, the robot records a laser intersection point. A second point is then recorded along the axis of the first laser beam. A third point is then recorded along the axis of the second laser beam. Once all three (3) points are known, the robotic reference frame is generated. Alternatively, in another preferred embodiment of the calibration system of the present invention, the robotic reference frame is defined by the first and second intersecting laser beams. The robotic reference frame is then used to adjust the angular position of the robot tool, which can involve adjusting roll, pitch and/or yaw of said robot tool. The robotic reference frame is the recorded in the real world position/ shop floor position. The robot's path is then adjusted to the correct robotic reference frame. The robot's path was generated in CAD and downloaded in CAD to this reference frame. When tools are assembled and lagged to the shop floor, they don't match the CAD world. This method is applicable for all manufacturing processes including, but not limited to, spot welding, material handling, MIG welding, assembly, cutting, painting and coating, and polishing and finishing.
[0017] The adjusting means is a manual robotic tool finder. The adjusting means includes means for retaining the manual robotic tool finder onto a robot tool. The adjusting means enables adjustment of the angular positions of the robot tool relative to the robotic reference frame. The manual robotic tool finder enables generation of the robotic reference frame.
[0018] The manual robotic tool finder, in use, enables user alignment of the robot work path by moving the robot into the path of the first or second laser beam until either the first or second laser beam is visible unobstructed through a first or second passageway. The first passageway enables a first laser beam to pass through unobstructed and the second passageway enables a second laser beam to pass through unobstructed. The second passageway intersects the first passageway. The manual robotic tool finder includes a closed position and an open position. The open position enables access to the first and the second passageways.
[0019] This technology enables the user to visually see the robotic reference frame, the frame in space that is relative to an industrial robot and work piece tool that is otherwise abstract and cannot be seen. Enabling the user to visually see the robotic reference frame on the manufacturing shop floor will enable the user to adjust the robotic frame to the manufacturing shop floor environment and, thereby, correct a robotic path or off-line program to obtain accuracy.
[0020] For a complete understanding of the robot calibration system of the present invention, reference is made to the following detailed description and accompanying drawings in which the presently preferred embodiments of the invention are shown by way of example. As the invention may be embodied in many forms without departing from the spirit or essential characteristics thereof, it is expressly understood that the drawings are for purposes of illustration and description only, and are not intended as a definition of the limits of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 depicts a perspective view of the robot calibration system of the present invention, the system comprising a robot having a robot tool, and a first preferred embodiment of a work object.
[0022] FIG. 2 depicts a perspective view of a first preferred embodiment of the work object for use with the robot calibration system of FIG. 1 , the work object having two beam-projecting lasers being used for aligning the laser intersection point with the robot tool. “DETAIL A” is a simplified representation of the angular positions (R x , R y , and R z ) of the robot tool that are adjustable by the robot calibration system of the present invention.
[0023] FIG. 3 depicts a perspective view of the work object of FIG. 2 positioned on a fixture with the robot tool being positioned at the laser intersection point of the work object.
[0024] FIG. 4 depicts a perspective view of the work object of FIG. 2 positioned on the fixture with the robot tool being positioned at a second point along the axis of the first laser beam projected from the work object.
[0025] FIG. 5 depicts a perspective view of the work object of FIG. 2 positioned on the fixture with the robot tool being positioned at a third point along the axis of the second laser beam projected from the work object.
[0026] FIG. 6A depicts a first perspective view of a second preferred embodiment of the work object for use with the robot calibration system of the present invention, the work object having two beam-projecting lasers being used for aligning the laser intersection point of a robot tool. FIG. 2B depicts a second perspective view of the preferred embodiment of the work object of FIG. 2A . FIG. 6C depicts a third perspective view of the preferred embodiment of the work object, similar to the work object shown in FIG. 6A for mounting on a numerical control block or a NAAMS mounting.
[0027] FIG. 7 depicts a perspective view of the robot calibration system of the present invention, with the work object of FIGS. 6A and 6B positioned on a fixture, with the robot tool being aligned relative to the laser intersection point of the work object.
[0028] FIG. 8 depicts a perspective view of the robot calibration system of the present invention, with the work object of FIGS. 6A and 6B positioned on the fixture as shown in FIG. 7 , with the robot tool being positioned at a second point along the axis of the first laser beam projected from the work object.
[0029] FIG. 9 depicts a perspective view of the robot calibration system of the present invention, with the work object of FIGS. 6A and 6B positioned on the fixture as shown FIG. 7 , with the robot tool being positioned at a third point along the axis of the second laser beam projected from the work object.
[0030] FIG. 10 depicts a perspective view of a fourth preferred embodiment of the work object for use with the robot calibration system of the present invention, the work object having two beam-projecting laser beams being used for aligning the laser intersection point with the robot tool.
[0031] FIG. 11 depicts a perspective view of the preferred embodiment of a manual robotic tool finder for use with the robot calibration system of the present invention.
[0032] FIG. 12 depicts a perspective view of the manual robotic tool finder of the FIG. 11 from above with the upper and lower jaws separated.
[0033] FIG. 13 depicts a perspective view of the manual robotic tool finder of the FIG. 11 from below with the upper and lower jaws separated.
[0034] FIG. 14 depicts a perspective view of the manual robotic tool finder of FIG. 11 , the manual robotic tool finder being mounted onto a weld gun.
[0035] FIG. 15 depicts a perspective view of a second preferred embodiment of the robot calibration system of the present invention, the robot calibration system includes the work object of FIGS. 6A and 6B being mounted on a fixture, and the manual robotic tool finder of FIG. 11 being mounted on a weld gun and positioned at the laser intersection point of the work object.
[0036] FIG. 16 depicts a second perspective view of the second preferred embodiment of the robot calibration system of FIG. 15 , the manual robotic tool finder still being mounted onto the weld gun with the robot tool being positioned at a second point along the axis of the first laser beam projected from the work object.
[0037] FIG. 17 depicts a third perspective view of the second preferred embodiment of the robot calibration system of FIG. 15 , the manual robotic tool finder still being mounted onto the weld gun with the robot tool being positioned at a third point along the axis of the second laser beam projected from the work object.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0038] Referring now to the drawings, FIG. 1 depicts the robot calibration system of the present invention. A first preferred embodiment of the work object [ 120 ] is combined with a robot [ 50 ] and robot tool [ 30 ]. The robot tool [ 30 ] is a tool used in any number of manufacturing applications including, but not limited to, spot welding, material handling, MIG welding, assembly, cutting, painting and coating, and polishing and finishing.
[0039] FIG. 2 depicts a second preferred embodiment of the work object [ 120 ]. An “E-shaped” structure lies horizontally and is positioned at the center of a frame comprising a horizontal frame member [ 17 ] crossing a vertical frame member [ 18 ]. Extending along the horizontal frame member [ 17 ] are three parallel arms which combine to form the squared “E-shaped” structure [ 25 A] which is horizontally aligned and generally centrally disposed relative to horizontal frame member [ 17 ] and vertical frame member [ 18 ]. The center arm ( 27 C) of the E-shaped structure [ 25 A] is shorter than the two end arms [ 27 A and 27 B].
[0040] A first laser beam [ 22 ] is emitted from the shortened center arm of the “E-shaped” structure [ 25 A] disposed at the proximate center of the work object [ 120 ]. A second laser beam [ 24 ] is emitted from one of the arms [ 27 A] of the E-shaped structure [ 25 A] and is directed into and through an opening [ 29 ] in the opposing arm [ 27 B]. The laser beams [ 22 and 24 ] are preferably red laser modules, having focusable dots (3.5v-4.5v 16 mm 5 mw). A robotic reference frame [ 35 ] is defined by the laser intersection point and the first and second laser beams [ 22 and 24 ].
[0041] The work object [ 120 ] is used to calibrate the work path of a robot tool [ 30 ] based upon a point where the two laser beams [ 22 and 24 ] intersect, called the laser intersection point [ 26 ] of the robot tool [ 30 ] (see FIG. 3 ). The laser intersection point [ 26 ] of the robot tool [ 30 ] is defined in three dimensions (X, Y, and Z) and relative to their rotational axes R x (pitch), R y (yaw), and R z (roll).
[0042] As best shown in FIGS. 6A and 6B , the work object [ 120 ] includes two (2) lasers [ 12 and 14 ] positioned onto a work piece or robot tool [ 30 ], at a known location with the two laser beams [ 22 and 24 ] intersecting at a 90 degree angle and continuing to project outward. The mounting is preferably an NC block or a NAAMS mounting pattern [ 47 ]. The laser intersection point [ 26 ] of the robot tool [ 30 ] defines the correct location of the robotic reference frame [ 35 ]. To accomplish this, the robot [ 50 ] will record a laser intersection point [ 26 ]. A second point [ 23 ] is then selected along the axis of the first laser beam [ 22 ] at a robot path tag [ 75 ] (see FIG. 4 ). A third point [ 25 ] is then selected along the axis of the second laser beam [ 24 ] at another robot path tag [ 75 ] (see FIG. 5 ).
[0043] In other words, the robotic reference frame [ 35 ] is defined by the two intersecting laser beams [ 22 and 24 ]. Once all three ( 3 ) points [ 23 , 25 and 26 ] are known, the robotic reference frame [ 35 ] is generated. The robotic reference frame [ 35 ] is then used to adjust the angular position of the robot tool [ 30 ], which can involve adjusting either roll and yaw, roll and pitch, yaw and pitch, or roll yaw and pitch of said robot tool [ 30 ]. This method is applicable for all robotic processes, including but not limited to, spot welding, material handling, MIG welding, assembly, cutting, painting and coating, and polishing and finishing.
[0044] FIGS. 6A and, 6 B depict a second preferred embodiment of the work object [ 20 ]. The work object [ 20 ] preferably has two lasers [ 12 and 14 ] securely mounted therein, each laser emitting a laser beam [ 22 and 24 , respectively] therefrom. The lasers are preferably mounted in work object [ 20 ] such that the laser beams [ 22 and 24 ] intersect each other at a 90° angle. The two laser beams [ 22 and 24 ] define a laser intersection point [ 26 ]. The mounting is preferably a numerical control (NC) block or a NAAMS mounting pattern [ 47 ], attached to the work object [ 20 ] with a wedge [ 46 ]. FIG. 6C depicts a third perspective view of the preferred embodiment of the work object, similar to the work object shown in FIG. 6A for mounting on a numerical control block or a NAAMS mounting.
[0045] FIG. 7 depicts the robot calibration system of the present invention as installed on a manufacturing shop floor, preferably an automotive shop floor. The technology enables the user to visually see a robotic reference frame [ 35 ] (a frame in space that is relative to an industrial robot) that is otherwise abstract and cannot be seen. Enabling the user to visually see the robotic reference frame [ 35 ] on the manufacturing shop floor enables the user to adjust the robotic reference frame [ 35 ] to the manufacturing shop floor environment and, thereby, correct a robotic path or off-line program to obtain accuracy.
[0046] The work object [ 20 ] includes two (2) laser beams positioned onto a work piece or tool, at a known location with the two laser beams [ 22 and 24 ] intersecting at a 90° angle at a laser intersection point [ 26 ] and continuing to project outward.
[0047] The laser intersection point [ 26 ] defines the correct location of the robotic reference frame [ 35 ], and is used to calibrate a robot work path on a manufacturing shop floor. To define the robotic reference frame [ 35 ], the robot will record a laser intersection point [ 26 ] at the intersection of the two (2) laser beams [ 22 and 24 ]. A second point [ 23 ] is then selected along the axis of the first laser beam [ 22 ] at a robot path tag [ 75 ] (see FIG. 8 ). A third point [ 25 ] is then selected along the axis of the second laser beam [ 24 ] at another robot path tag [ 75 ] (see FIG. 9 ).
[0048] In other words, the robotic reference frame [ 35 ] is defined by the two intersecting laser beams [ 22 and 24 ]. Once all three (3) points [ 22 , 24 , and 26 ] are known, the robotic reference frame [ 35 ] is generated. The robotic reference frame is then used to adjust the angular position of the robot tool [ 30 ], which enables adjustment of roll, yaw, pitch, roll and yaw; roll and pitch; yaw and pitch; or roll, yaw, and pitch of said robot tool [ 30 ]. This method is applicable to all robotic processes including, but not limited to, spot welding, material handling, MIG welding, assembly, cutting, painting and coating, and polishing and finishing.
[0049] Using computer-aided design (CAD) simulation software, the user selects a position on the tool that is best suited to avoid crashes with other tooling and for ease of access for the robot or end-of-arm tooling. The off-line programs are then downloaded relative to the work object [ 20 ]. The work object [ 20 ] preferably mounts onto a fixture [ 39 ] using an NC block or standard NAAMS hole pattern mount [ 47 ]. The mounts are preferably laser cut to ensure the exact matching of hole sizes for the mounting of parts. The robot technician then manipulates the robot tool [ 30 ] into the work object [ 20 ] and aligns it with the laser beams [ 22 and 24 ] to obtain the difference between the CAD world and manufacturing shop floor. This difference is then entered into the robot [ 50 ] and used to define the new robotic reference frame [ 35 ]. This calibrates the off-line programs and defines the distance and orientation of the robot tool [ 30 ], fixture [ 39 ], and peripheral.
[0050] The off-line programming with the work object [ 20 ] on the fixture [ 39 ] enables the work object [ 20 ] to be touched up to the “real world position” of the fixture [ 39 ] relative to the robot [ 50 ]. If the fixture [ 39 ] ever needs to be moved or is accidently bumped, the user can simply touch up the work object [ 20 ] and the entire path shifts to accommodate the change.
[0051] The first and second laser beams [ 22 and 24 ] are projected onto known features of the robot tool [ 30 ], and then used to calibrate the path of the robot tool [ 30 ] and measure the relationship of the fixture [ 39 ] relative to the robot tool [ 30 ].
[0052] The work object [ 20 ] has a zero point, a zero reference frame, and a zero theoretical frame in space, which is positioned on the fixture [ 39 ].
[0053] The work object [ 20 ] is placed onto the fixture [ 39 ], visually enabling the laser intersection point [ 26 ] of the robot tool [ 30 ] to be orientated into the work object
[0054] obtaining the “real-world” relationship of the robot tool [ 30 ] to the fixture [ 39 ] while updating the work object [ 20 ] to this “real-world” position.
[0055] The work object [ 20 ] requires that its position correlate with the position of the robot tool [ 30 ] to calibrate the path of the robot tool [ 30 ] while acquiring the “real-world” distance and orientation of the fixture [ 39 ] relative to the robot tool [ 30 ]. The work object [ 20 ] must have a well-defined location on the manufacturing shop floor, and its position relative to the fixture [ 39 ] must be known.
[0056] The work object [ 20 ] is used to calibrate a “known” calibration device or frame (robotic simulation CAD software provided calibration device). The robotic calibration method of the present invention works by projecting laser beams to a known X, Y, and Z position and defining known geometric planes used to adjust the roll, yaw, and pitch of the robot tool [ 30 ] relative to the laser intersection point [ 26 ].
[0057] The laser beams [ 22 and 24 ] are projected onto the end of the robot tool [ 30 ] (weld gun, material handler, MIG torch, etc.) where the user will manipulate the robot with end-of-arm tooling into the laser beams [ 22 and 24 ] to obtain the positional difference between the “known” off-line program (simulation provided calibration device) and the actual (manufacturing shop floor) calibration device. The reverse is also true. For instance, a material handler robot can carry the work object [ 20 ] to a known work piece with known features.
[0058] Using CAD simulation software, the CAD user selects a position on the tool to place the robotic work object calibration system that is best suited to avoid crashes with other tooling and for ease of access for the robot [ 50 ] or end-of-arm tooling. The off-line programs are then downloaded relative to this work object [ 20 ]. The visual work object [ 20 ] will be placed onto the tool or work piece in the position that was defined by the CAD user on the manufacturing shop floor. The robot technician then manipulates the robot tool [ 30 ] into the work object [ 20 ], aligning it to the laser beams [ 22 and 24 ] to obtain the difference between the CAD world and manufacturing shop floor. This difference is then entered into the robot and used to define the new calibration device, thus calibrating the off-line programs and defining the distance and orientation of the robot tool [ 30 ], fixture [ 39 ], peripheral, and other key components.
[0059] The work object [ 20 ] calibrates the paths to the robot [ 50 ] while involving the calibration of the peripherals of the robot [ 50 ].
[0060] The work object [ 20 ] aids in the kitting, or reverse engineering, of robotic systems for future use in conjunction with robotic simulation software. This enables integrators the ability to update their simulation CAD files to the “real world” positions.
[0061] The technology uses existing body-in-white procedures, personal computers and software and ways of communicating information amongst the trades.
[0062] FIG. 10 depicts a perspective view of a third preferred embodiment of the work object [ 220 ] for use with the robot calibration system of the present invention, the work object [ 220 ] having two laser beams [ 22 and 24 ] which define a laser intersection point [ 26 ]. In this embodiment, one of the arms of the E-shaped structure of the second preferred embodiment of the work object [ 120 ] is truncated, creating an F-shaped structure, enabling the second laser beam [ 24 ] to extend beyond the work object [ 220 ], unimpeded.
[0063] The work object [ 220 ] includes a horizontal frame member [ 17 ] and a vertical frame member [ 18 ]. Extending along the horizontal frame member [ 17 ] are two arms parallel which combine to form a squared “F-shaped” structure [ 25 B] which is horizontally aligned and generally centrally disposed relative to horizontal frame member [ 17 ] and vertical frame member [ 18 ]. A first laser beam [ 22 ] is emitted by a laser disposed in the center arm of the F-shaped structure [ 25 B]. A second laser beam [ 24 ] is emitted from one of the arms [ 27 A] and is directed unimpeded past the work object [ 220 ]. The robotic reference frame [ 35 ] is defined by the laser intersection point [ 26 ] and the first and second laser beams [ 22 and 24 ].The mounting is preferably an NC block or NAAMS mounting pattern [ 47 ].
[0064] The first laser beam [ 22 ] intersects the second laser beam [ 24 ] at the laser intersection point [ 26 ]. The first and second laser beams [ 22 and 24 ] intersect at a 90° angle. The robotic reference frame [ 35 ] is defined by the laser intersection point [ 26 ] and the first and second laser beams [ 22 and 24 ].
[0065] The work object [ 220 ] is used to calibrate the work path of a robot tool [ 30 ] based on a laser intersection point [ 26 ] of the robot tool [ 30 ] (see FIGS. 7 , 8 and 9 for reference). The laser intersection point [ 26 ] of the robot tool [ 30 ] is defined in three dimensions (X, Y, and Z) and relative to the rotational axes R x (pitch), R y (yaw), and R z (roll) as shown in DETAIL “A”.
[0066] FIGS. 11 , 12 and 13 depict a preferred embodiment of a manual robotic tool finder [ 80 ] for use in the robot calibration system of the present invention. The manual robotic tool finder [ 80 ] has an upper jaw [ 83 ] and a lower jaw [ 93 ]. A pair of passageways extend through each jaw normal to each other forming a pair of intersecting passageways [ 84 and 86 ] through said upper jaw [ 83 ] and a pair of passageways [ 94 and 96 ] through said lower jaw [ 93 ]. A pair of spring grips [ 98 ] positioned at the rear of the device enables the device to be opened and closed to gain access to the passageways. The manual robotic tool finder [ 80 ] is placed over the laser intersection point [ 26 ] of the work object [ 20 , 120 , or 220 ]. The manual robotic tool finder [ 80 ] calibrates the robot work path. The manual robotic tool finder [ 80 ] includes a mount opening [ 52 ] extending therethrough that is used for mounting the device over the weld tips of a weld gun or pin on an end-of-arm-tooling, or other attachment to a robot tool [ 30 ].
[0067] FIG. 14 depicts the manual robotic tool finder [ 80 ] mounted in a robot tool [ 30 ].
[0068] FIGS. 15 , 16 , and 17 depict a second preferred embodiment of the robot calibration system [ 10 ] of the present invention. The manual robotic tool finder [ 80 ] is mounted on a robot tool [ 30 ] being used with the work object [ 20 ] mounted on fixture [ 39 ]. The manual robotic tool finder [ 80 ] cooperatively engages with the work object [ 20 ], which defines a robotic reference frame [ 35 ] (a frame in space that is relative to an industrial robot [ 50 ] and work piece tool) that is otherwise abstract and cannot be seen. The work object [ 20 ] includes two lasers [ 12 and 14 ] mounted onto a work piece or tool, at a known location with the two laser beams [ 22 and 24 ] intersecting at a 90° angle and continuing to project outward. The mounting is preferably an NC block or a NAAMS mounting pattern [ 47 ]. The laser intersection point [ 26 ] of the robot defines the correct location of the robotic reference frame [ 35 ]. To accomplish this, the robot will record a laser intersection point [ 26 ] (see FIG. 15 ). A second point [ 23 ] is then selected along the axis of the first laser beam [ 22 ] at a robot path tag [ 75 ] (see FIG. 16 ). A third point [ 25 ] is then selected along the axis of the second laser beam [ 24 ] at another robot path tag [ 75 ] (see FIG. 17 ).
[0069] The robot calibration systems of the present invention as described herein are compatible with robotic simulation packages, including but not limited to, Robcad® which is a registered trademark of Tecnomatix Technologies Ltd., Delmia® which is a registered trademark of Dassault Systèmes, Roboguide® which is a registered trademark of Fanuc Ltd. Corp., and RobotStudio® which is a registered trademark of ABB Corp.
[0070] Throughout this application, various Patents and Applications are referenced by number and inventor. The disclosures of these Patents/Applications in their entireties are hereby incorporated by reference into this specification in order to more fully describe the state of the art to which this invention pertains.
[0071] It is evident that many alternatives, modifications, and variations of the robot calibration systems of the present invention will be apparent to those skilled in the art in light of the disclosure herein. It is intended that the metes and bounds of the present invention be determined by the appended claims rather than by the language of the above specification, and that all such alternatives, modifications, and variations which form a conjointly cooperative equivalent are intended to be included within the spirit and scope of these claims.
Parts List
[0000]
10 . Robot calibration system
12 . First laser
14 . Second laser
17 . Horizontal frame member
18 . Vertical frame member
20 . Work object (1st embodiment)
22 . First laser beam
23 . Second point
24 . Second laser beam
25 . Third point
25 A. E-shaped structure with opening
25 B. F-shaped structure
26 . Laser intersection point
27 A. E-shaped member end arm w/laser
27 B. E-shaped member end arm w/opening
27 C. E-shaped member center arm
29 . Opening
30 . Robot tool
35 . Robotic reference frame
39 . Fixture
46 . Wedge
47 . NC block or NAAMS mount
50 . Robot
52 . Mount opening
75 . Robot path tag
80 . Manual robotic tool finder
81 . Laser beam alignment hole # 1
82 . Laser beam alignment hole # 2
83 . Upper jaw
84 . Upper jaw laser beam alignment passageway # 1
86 . Upper jaw laser beam alignment passageway # 2
93 . Lower jaw
94 . Lower jaw laser beam alignment passageway # 1
96 . Lower jaw laser beam alignment passageway # 2
98 . Spring grips
120 . Work object (2 nd embodiment)
220 . Work object (3 rd embodiment) | The robot calibration systems combine a work object with an industrial robot and a robot tool. Three different work objects can be used with the system. This technology enables the user to visually see a robotic reference frame, a frame in space that is relative to the industrial robot and workpiece that is otherwise abstract. Enabling the user to visually see the robotic reference frame on the manufacturing shop floor enables adjustment of the robotic frame to the shop floor and correction of a robotic path or off-line program to enhance accuracy. Two laser beams are emitted and intersect at a laser intersection point. The laser intersection point and the laser beams are then used to define a robotic reference frame. The technology improves cost and time factors in applications where absolutely accurate robots are not necessary. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation application, under 35 U.S.C. §120, of copending international application No. PCT/EP2011/060734, filed Jun. 27, 2011, which designated the United States; this application also claims the priorities, under 35 U.S.C. §119, of German patent applications No. DE 10 2010 030 551.0, filed Jun. 25, 2010 and DE 10 2011 007 815.0, filed Apr. 20, 2011; the prior applications are herewith incorporated by reference in their entireties.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention relates to a method for producing a ceramic substance, which is suitable for highly rigid structural components and has a particularly high level of homogeneity in view of the density of the substance components and the other chemical and physical properties.
[0003] A ceramic substance has a large number of advantageous physical, in particular mechanical and chemical, properties. Due to these properties, substance compositions and materials of this type can be used advantageously in many technical fields of application.
[0004] A problem with existing ceramic substances, however, is that a particularly high level of effort is often necessary to ensure a high level of homogeneity. This is often impossible to achieve satisfactorily, particularly with complex three-dimensional structures.
[0005] A high level of homogeneity is necessary, however, in ceramic substances of this type so as to meet high quality requirements.
SUMMARY OF THE INVENTION
[0006] The object of the invention is to develop a method for producing a ceramic substance, in which a high level of homogeneity of the ceramic substance and of the other chemical and physical properties can be achieved in a particularly simple and reliable manner.
[0007] The present invention is a method for producing ceramic substance. The method more specifically contains the following steps: producing a homogeneous mixture containing carbon fibers having a fiber length distribution D 50 <15 μm and at least one powdery and carbonizable binder, compacting the homogeneous mixture under the action of pressure, thermally treating for carbonizing, or for carbonizing and graphitizing, the compacted homogeneous mixture to obtain a carbon substance, and siliconizing the carbon substance to obtain the ceramic substance.
[0008] A particularly high level of homogeneity of the mixture is achieved by intensive mixing with the binder to be supplied.
[0009] Fiber length distributions with stringent exclusion dimensions can indeed often be produced, that is to say distributions in which there are no particles of which the diameter exceeds or fails to reach specific limits. However, it is often also sufficient to specify fiber length distributions on the basis of specific D values. The marginal condition that the fiber length distribution has a D 50 value of less than 15 μm is often sufficient for specific embodiments and fields of application.
[0010] The carbon fibers preferably have a fiber length distribution of D 95 <30 μm.
[0011] Further advantages in terms of the homogeneity of the ceramic substance to be produced emerge if a number of marginal conditions are imposed within the context of the specification of mutually independent D values. In this case, the specification of the D 95 value may be considered alternatively or additionally to the specification of the D 50 value described further above or of other D values.
[0012] It is preferable if the powdery binder contains powdery resin, in particular powdery phenolic resin.
[0013] The powdery binder preferably has a particle size distribution D 50 <100 μm.
[0014] The homogeneity of the ceramic substance to be produced is provided in particular if the described properties for the fiber length distributions are not only required for the starting substance(s), but also for the additions, that is to say in particular for the binder(s).
[0015] The mixing ratio in the homogeneous mixture and the pressure during the compacting process, and/or the temperature during the thermal treatment, are preferably selected in such a way that the carbon substance has a density in the range of approximately 0.5 g/cm 3 to approximately 0.85 g/cm 3 .
[0016] This may preferably occur on the basis of at least one of the relationships disclosed in Table 2 in FIG. 5 and in Graph 2 in FIG. 6 .
[0017] During the step of mixing or intensive mixing, one or more additions may be added to form the homogeneous mixed powder, in particular additives and/or fillers.
[0018] As a result of the use of suitable binders, additives and/or fillers, the quantity and concentration thereof and incorporation thereof into the structure of the ceramic substance to be produced may contribute to the properties of the ceramic substance to a large extent.
[0019] During siliconization, the density of the ceramic substance is preferably set in the range of approximately 2.8 g/cm 3 to approximately 3.1 g/cm 3 .
[0020] This may preferably be implemented on the basis of at least one of the relationships disclosed in equation (3)
[0000]
ρ
sil
=
-
1.7655
·
ρ
2
g
/
cm
3
+
3.1006
·
ρ
+
1.6223
·
g
/
cm
3
,
(
3
)
in Table 3 in FIG. 7 and in Graph 3 in FIG. 8.
[0021] In this case ρ sil and ρ, denote the densities of the siliconized and unsiliconized form of the compacted homogeneous mixture obtained.
[0022] As was explained above in detail in conjunction with the shaping, it is also possible to exert control during the process of siliconization via a closed formula expression or to exert control via the empirical values by a graph evaluation or by a table-readout method or table-look-up method.
[0023] The density, in particular of the siliconized form, of the obtained ceramic substance may preferably be set directly or indirectly on the basis of at least one of the relationships described in equation (4)
[0000]
E
GPa
=
461.79
·
ρ
g
/
cm
3
-
1040.4
,
(
4
)
[0000] or disclosed in Table 4 in FIG. 5 or in Graph 4 in FIG. 10 .
[0024] In this case, E denotes the modulus of elasticity, in particular of the siliconized form, of the obtained ceramic substance or the preliminary product of the ceramic substance.
[0025] Even if the modulus of elasticity is controlled, the corresponding possibilities for control are provided during the shaping process or during siliconization.
[0026] In addition to the control of the modulus of elasticity, other mechanical properties can also be set accordingly, for example the hardness or the extension and compression behavior, but also thermal or electrical properties, for example thermal expansibility or thermal conductivity, via the shaping process, that is to say ultimately via the pressure conditions, but also via the type of carbonization and/or siliconization and ultimately also via the proportions of the starting substance.
[0027] It is preferable if the homogeneous mixture contains 20-50% by weight binder and 50-80% by weight carbon fibers, preferably 30-40% by weight binder and 60-75% by weight carbon fibers.
[0028] A compressive force in the range of approximately 1.0 MPa to approximately 4.0 MPa is preferably set during the step of compaction.
[0029] During the step of compaction, the homogeneous mixture is preferably molded in a mold to form a compression molding, and the compression molding is converted in the thermal treatment step into a molded article made of the carbon substance.
[0030] Processes of dedusting, granulation and/or intermediate storage may be implemented after the step of mixing or intensive mixing and before the step of molding.
[0031] A step of carbonizing the obtained compacted homogeneous mixture or the preform of the homogeneous substance composition may occur, in particular by pyrolysis, after the step of molding.
[0032] A step of siliconizing the obtained compacted homogeneous mixture may occur after the step of molding and in particular after the step of carbonization.
[0033] Due to the process of dedusting, that is to say the removal of particle fractions, the ease of handling of the obtained mixed powder may be increased and a risk of explosion when handling the mixed powder may be reduced. One aspect of the ease of handling is also the reduction of impurities in the working environment as a result of the removal of dusts.
[0034] Granulation substantially consists of the formation of mesoscopic particles, clusters or aggregates, for example in the range of some 100 μm to a few mm in substantially solid form, which provide, however, the homogeneous distribution of the starting substances prepared in the mixed powder in a homogeneously mixed manner. A granulate of this type can be stored intermediately, provided the mixed powder as such is suitable therefor, and can be handled, portioned and further processed as required in a particularly suitable manner.
[0035] The compression molding is preferably cured before carbonization.
[0036] It is preferable if a plurality of molded articles made of carbon substance are produced that are joined together by an adhesive, in particular a carbonizable adhesive, before the step of siliconization to obtain a molded article arrangement.
[0037] In a preferred embodiment, the carbonizable adhesive contains resin, in particular phenolic resin and silicon carbide powder.
[0038] The silicon carbide powder has a mean particle diameter of 1-50 μm, preferably 3-20 μm, more preferably 5-10 μm.
[0039] The carbonizable adhesive contains 5-50% by weight water, 20-80% by weight silicon carbide powder and 10-55% by weight resin, preferably 10-40% by weight water, 30-65% by weight silicon carbide powder and 20-45% by weight resin, more preferably 15-25% by weight water, 45-55% by weight silicon carbide powder and 27-33% by weight resin.
[0040] The carbonizable adhesive contains less than 10% by weight, in particular less than 3% by weight, and in particular no, filler made of carbon substance.
[0041] The formation of the ceramic substance or of the preliminary product of the ceramic substance may include a step of compression or compression molding and possibly of curing. The obtained mixed powder or its granulate are thus converted by a corresponding shaping process into the ceramic substance according to the invention, wherein a curing process is optionally included. The shaping via a compression process, that is to say via the application of a mechanical pressure, leads to a compaction of the substance distribution already present in the powder or granulate as a homogeneous mixture. Corresponding physical and chemical properties of the finished, demolded homogeneous substance composition can then also be determined, more specifically homogeneously, within wide ranges as a result of the design of the compression process, that is to say as a result of the pressure and/or temperature distributions over time and space.
[0042] For example, this may occur on the basis of at least one of the relations disclosed by the following equations (1) and (2)
[0000]
ρ
1
g
/
cm
3
=
-
0.0084
·
ρ
2
MPa
2
+
0.1126
·
ρ
MPa
+
0.5043
,
(
1
)
ρ
2
g
/
cm
3
=
-
0.0067
·
ρ
2
MPa
2
+
0.0986
·
ρ
MPa
+
0.4836
,
(
2
)
[0000] by Table 1 in FIG. 3 and/or by Graph 1 in FIG. 4 .
[0043] In this case, ρ 1 , ρ 2 denote the density of the obtained ceramic substance or of the preliminary product of the ceramic substance, in particular after carbonization, and p denotes the pressure during the molding step.
[0044] The relationships given here, whether describable in closed form or given exclusively empirically, can be configured with shaping processes corresponding to a desired substance density, which result in a desired substance density after the shaping process. The respective desired substance density may optionally also be derived from other physical-chemical relations, such that the pressure parameters that lead to a desired property profile with the homogeneous substance composition according to the invention can be determined in a series of empirical conclusions.
[0045] When controlling corresponding methods, the closed mathematical relationships or else the empirical values are provided from graphs or tables, wherein “table-readout methods” or “table-look-up methods” may also be considered.
[0046] It is often desirable to carry out specific processing procedures in the carbon substance of the preliminary product of the ceramic substance according to the invention. In particular, this concerns joining processes or else mechanical working by drilling, milling, grinding, planning, since these can be carried out more easily on the carbon substance of the preliminary product of the ceramic substance according to the invention, for example due to the weaker hardness or brittleness in the carbon substance.
[0047] A sequence of further conversion processes may directly adjoin the shaping process however, that is to say may directly adjoin the preliminary product inter alia carbonization and/or siliconization, which lead to the structural reshaping already discussed above.
[0048] It is particularly preferable if the molded article arrangement is worked by removal of carbon substance from the molded article arrangement before the siliconization step, such that a preform made of carbon substance with a predefined shape is produced.
[0049] The preform is preferably carbonized before siliconization.
[0050] As a result of this approach, substance properties of the substance composition can be set accordingly, namely with regard to density, the proportion of carbon, silicon and possibly other components, and with regard to the formation and modulation of the structural properties, such that the resilience, strength, hardness, thermal conductivity and other substance properties can be set within wide ranges in a targeted manner and can be adapted to the respective application and use.
[0051] In a preferred embodiment, the carbon fibers are produced by grinding and carbonizing viscous and/or cellulose fibers, in particular by first grinding the fibers and then carbonizing said fibers.
[0052] In accordance with a further aspect of the present invention, a ceramic substance for a ceramic material is also proposed, in particular for highly rigid structural components or the like, and is, or has been, formed in the above-described manner in accordance with a method according to the present invention.
[0053] If it has been molded accordingly within the scope of the shaping process, the ceramic substance according to the invention can be used directly in an application. However, it is also possible to form the ceramic substance in plate form initially, to then join these plates two-dimensionally so as to form an encasing body for a larger three-dimensional structure or a large, extensive flat article, which is then used, possibly following carbonization and/or siliconization, as a basis for the production of a product by working out the correspondingly desired three-dimensional structure or flat form.
[0054] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0055] Although the invention is illustrated and described herein as embodied in a method for producing a ceramic substance for a ceramic material, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
[0056] The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0057] FIGS. 1A-1C are schematic flow diagrams illustrating details of one embodiment of a method for producing a ceramic substance for a ceramic material according to the invention;
[0058] FIG. 2A-2H are illustrations showing different intermediate stages that are reached with one embodiment of the method for producing a ceramic substance for a ceramic material according to the invention;
[0059] FIG. 3 is a table showing how in one embodiment of the method according to the invention for producing a ceramic substance for a ceramic material, the density of a carbon substance according to the invention can be set by pressure during the shaping process;
[0060] FIG. 4 is a graph showing how in one embodiment of the method according to the invention for producing the ceramic substance for the ceramic material, the density of the carbon substance according to the invention can be set by pressure during the shaping process;
[0061] FIG. 5 is a table showing how an uptake of silicon during the process of siliconization, in one embodiment of the method according to the invention for producing the ceramic substance for the ceramic material, can be controlled via the density of the preliminary product of the ceramic substance;
[0062] FIG. 6 is a graph showing how the uptake of silicon during the process of siliconization, in one embodiment of the method according to the invention for producing the ceramic substance for the ceramic material, can be controlled via the density of the preliminary product of the ceramic substance;
[0063] FIG. 7 is a table showing how in one embodiment of the method according to the invention for producing the ceramic substance for the ceramic material, the density of the ceramic substance according to the invention or of a preliminary product thereof can be controlled, following a process of siliconization, via the density of the unsiliconized form of the carbon substance or of the preliminary product;
[0064] FIG. 8 is a graph showing how in one embodiment of the method according to the invention for producing the ceramic substance for the ceramic material, the density of a ceramic substance according to the invention or of a preliminary product thereof can be controlled, following a process of siliconization, via the density of the unsiliconized form of the carbon substance or of the preliminary product;
[0065] FIG. 9 is a table showing how, in one embodiment of the method according to the invention for producing the ceramic substance for the ceramic material, the modulus of elasticity of one embodiment of the ceramic substance according to the invention or of the preliminary product thereof can be controlled via the density of the siliconized form of the carbon substance or the precursor thereof; and
[0066] FIG. 10 is a graph showing how, in one embodiment of the method according to the invention for producing the ceramic substance for the ceramic material, the modulus of elasticity of one embodiment of the ceramic substance according to the invention or of the preliminary product thereof can be controlled via the density of the siliconized form of the carbon substance or the precursor thereof.
DETAILED DESCRIPTION OF THE INVENTION
[0067] Embodiments of the present invention will be described hereinafter. All embodiments of the invention and their technical features and properties can be isolated individually or electively grouped together as desired and combined without restriction.
[0068] Structurally and/or functionally like, similar or identically acting features or elements will be denoted hereinafter in conjunction with the figures by like reference signs. A detailed description of these features or elements will not be repeated in each case.
[0069] Reference is first made to the drawings in general.
[0070] The present invention, inter alia, also relates to a production method for a ceramic substance, which is suitable for the production of highly rigid structural components.
[0071] A homogeneous starting substance is required for the production of highly rigid components.
[0072] Felt-based substances demonstrate inhomogeneous mechanical properties due to the structuring, namely due to their possible layered structure. With slip-cast SiSiC components, only low or thin wall thicknesses can be produced. Components having thicker wall thicknesses or thicker components establish relatively steep temperature gradients upon heating and cooling, which may lead to destruction of the component. Wood-based ceramics have a high shrink value of up to 70% in the production process and are therefore unsuitable as starting substance for complex geometries.
[0073] In accordance with the invention, it is therefore proposed for the production of a very homogeneous ceramic component to use homogeneous fine powder as a raw substance for a mixture with a binder, for example in the form of a phenolic resin powder. The starting components are mixed homogeneously in an intensive mixer and are then compressed to form plates for example.
[0074] To be able to process and handle the provided mixture of the starting components, these may be granulated and/or dedusted.
[0075] The substance densities of the compressed plates influence the subsequent substance properties from a chemical and physical, and in particular mechanical, point of view. All physical and chemical properties can thus be controlled, in part, by selective control of the substance density and homogeneity thereof.
[0076] To produce a ceramic substance 100 for a ceramic material 100 ′, it is proposed to convert at least one starting substance 10 in the form of a homogeneous powder having a fiber length distribution D 50 below 15 μm with at least one binder 20 in a form of a powder into a homogeneous mixed powder 30 by compacting the homogeneous mixture under an action of pressure S 2 so as to form therefrom the desired carbon substance by a corresponding shaping process S 3 .
[0077] Reference will now be made to the drawings in detail.
[0078] FIG. 1A shows a schematic flow diagram illustrating an embodiment of the method according to the invention for producing a ceramic substance 100 for a ceramic material 100 ′.
[0079] After an introductory processing step S 0 , the starting substance 10 and one or more additions, in particular a binder 20 and possibly also further additives or fillers, are provided in steps S 1 a and S 1 b in the provision step S 1 . Steps S 1 a and S 1 b can be carried out one after the other or parallel to one another.
[0080] In the subsequent step S 2 , the provided starting substances, namely the starting substance 10 and the one or more additions 20 , are combined in a mixing or intensive mixing process under the action of pressure to obtain a compacted homogeneous mixture.
[0081] An intermediate processing step Z may then optionally follow.
[0082] Next, the carbon substance is formed in step S 3 , more specifically as a result of thermal treatment to carbonize, or to carbonize and graphitize, the compacted homogeneous mixture.
[0083] After step S 3 , a further processing step W may follow, within the scope of which the substance resulting from the molding step S 3 is processed further.
[0084] The production method according to the invention ends in step S 4 with the siliconization of the carbon substance.
[0085] According to FIG. 1B , the intermediate processing step Z may include one or more processes of dedusting T 1 , granulation T 2 and/or intermediate storage T 3 in one embodiment of the production method according to the invention. The procedure and the advantages of these intermediate steps have already been explained within the scope of the general description of the invention.
[0086] According to FIG. 1C , the step of further processing W may include the further treatment and refining U of the obtained ceramic substance 100 as well as a final further processing step V, which ultimately delivers from the obtained ceramic substance 100 a ceramic material 100 ′ that is ready for production.
[0087] The actual further processing and refining portion U includes steps of carbonization U 1 , high-temperature treatment U 2 , possibly a mechanical working process U 3 and possibly siliconization U 4 .
[0088] The mechanical working U 3 and siliconization U 4 may be optional at this point if the intermediate product obtained after compression has the correct shape and/or premature siliconization would impede further working. In accordance with the further processing and refining portion U 4 , plates can thus be provided as intermediate products containing the ceramic substance 100 according to the invention.
[0089] During the actual further processing step V, intermediate products thus produced, for example plates or the like, can then be joined together in a first step V 1 . This is achieved, for example, by gluing or by pressing the products together, possibly with interspersion of powder from the same substance class as the carbon substance according to the invention for the plates or intermediate products. As a result of the joining process V 1 , an encasing body is provided, from which the actual product can then be worked, possibly by mechanical working V 2 , the actual product then being formed, possibly by siliconization V 3 , with corresponding mechanical properties via silicon uptake in the structure.
[0090] FIGS. 2A-2H shows an improved illustration again of intermediate stages A to H, which are achieved in one embodiment of the method according to the invention for producing a ceramic substance 100 for a ceramic material.
[0091] According to the intermediate state A in FIG. 2A , the starting substance 10 and a powdery and carbonizable binder 20 are first provided in homogeneous form, wherein corresponding criteria are to stipulated for the fiber length distributions; this concerns the starting substance 10 , but also the binder 10 in particular.
[0092] According to the intermediate state shown in FIG. 2B , the starting substance 10 and the additions 20 are mixed intensively in a vessel 40 by a mixer 41 .
[0093] The homogenous mixture 30 according to the intermediate state in FIG. 2C is produced as an intermediate product.
[0094] The homogeneous mixture 30 is then filled, according to FIG. 2D , into the vessel 42 of a compression device 42 , 43 and, in accordance with the intermediate state in FIG. 2E , is subjected to a pressure p, the compressive force, by a plunger 43 , in this case from one side.
[0095] During the transition to the state in FIG. 2F , the homogeneous mixture 30 is thus compacted under the pressure p into the shape of the vessel 42 by the action of the plunger 43 , such that, in accordance with FIG. 2G , the preliminary product 50 for the ceramic substance 100 according to the invention is produced. The ceramic substance is then produced by an intermediate processing step by carbonization and/or siliconization, FIG. 2H .
[0096] FIGS. 3 and 4 , in the form of a Table 1 and a Graph 1 respectively, show the relationship between the compressive force p during compaction of the homogeneous mixture 30 and the density ρ of the ceramic substance 100 , in particular after carbonization, in one embodiment of the method according to the invention.
[0097] Two series of empirical measurements at pressures between 1.0 MPa and 4.0 MPa are shown in Table 1 in FIG. 3 , the data of these series of measurements being shown in the graph by squares and by diamonds. A more detailed analysis reveals that the densities ρ 1 and ρ 2 of the series of measurements in the pressure ranges used can be described in each case by a polynomial of second degree.
[0098] The numerical values in Table 1, the information from Graph 1 and the functional relationships from the fitting curves for ρ 1 and ρ 2 can be used for the control of the density ρ by the compressive force p, as has already been described above in detail.
[0099] FIGS. 5 and 6 , with Table 2 and Graph 2 respectively, describe the silicon uptake in one embodiment of the method according to the invention after carbonization as a function of the density of the carbon substance before siliconization.
[0100] Table 2 in FIG. 5 shows four series of empirical measurements, which are represented in Graph 2 in FIG. 6 by diamonds, circles, triangles and squares.
[0101] Again, the numerical information from Table 2 and the information from Graph 2 can be used for the control of the silicon uptake by density in the carbon substance according to the invention after carbonization.
[0102] It is also conceivable that a fitting curve, for example in the form of a polynomial expression, is established on the basis of the data in Table 2, of which the parameters can then be used directly for the control of the relationship between silicon uptake and density in the production process.
[0103] Table 3 and Graph 3 in FIGS. 7 and 8 respectively describe the density of a CSiC substance, that is to say of a carbon-fiber-reinforced silicon carbide, as a function of the density of the CFC substance, that is to say of the carbon substance according to the invention after compression and possibly after carbonization.
[0104] From the relationships in Table 3 in FIG. 7 and in Graph 3 in FIG. 8 , it is possible to control the silicon uptake during siliconization by the density of the carbon substance according to the invention or of the preliminary product, and therefore by the corresponding compressive force and the intermixed components and particle size thereof. In this case too, the numerical values in Table 3, the Graph in FIG. 8 and in particular the parameters of the numerical fitting, in this case again in the form of a polynomial of second degree, can be used.
[0105] Table 4 and Graph 4 from FIGS. 9 and 10 respectively show how the modulus of elasticity E of the ceramic substance 100 according to the invention can be controlled by the density of the underlying siliconized substance.
[0106] A series of measurements for a carbon-fiber-reinforced silicon carbide is shown in Table 4 in FIG. 9 . Different carbon-fiber-reinforced silicon carbide substances having different densities have been produced, and the modulus of elasticity has been determined in each case.
[0107] The measurement results are illustrated in the Table and in Graph 4 in FIG. 10 , wherein a linear relationship is basically produced in the considered density range. In this case too, the numerical values in Table 4 from FIG. 9 , the information contained in Graph 4 from FIG. 10 and, lastly, the numerical parameters from the fitting curve can be used to control the properties, in particular the modulus of elasticity, of the ceramic substance 100 according to the invention or the preliminary product 50 thereof.
[0108] On the whole, it is found that a large part of the physical, mechanical, but also thermal and electrical properties for the ceramic substance 100 according to the invention or the preliminary product 50 thereof can be set in a controlled manner in accordance with the invention by the density and their homogeneity after the shaping process, wherein the type of starting substances, specifically the carbon-based or carbon-fiber-based or carbon-fiber-reinforced starting substance 10 and the binder 20 , and the fiber length distribution thereof, are also of significance however.
LIST OF REFERENCE SIGNS
[0000]
10 starting substance
20 addition, additive, binder, filler
30 mixed powder, mixture
30 ′ granulate
40 vessel, mixing vessel
41 mixer
42 vessel, compression mould
43 plunger
50 preliminary product of the ceramic substance according to the invention
100 homogeneous ceramic substance according to the invention
100 ′ material
ρ pressure, compressive force | A method for producing a ceramic substance includes producing a homogeneous mixture containing carbon fibers having a fiber length distribution of D 5 =<15 μm and at least one powdery and carbonizable binder. The homogeneous mixture is compacted under the action of pressure. The compacted homogeneous mixture is thermally treating for carbonizing, or for carbonizing and graphitizing, to obtain a carbon substance. The carbon substance is siliconized to obtain a ceramic substance. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to emergency brake control systems and more particularly to such systems used in hoists such as mine hoists employed to transport a conveyance between the ground and the surface level.
Generally, hoists of the type to which the invention pertains include a rotating drum driven by a motor, and a conveyance attached to the drum by means of a cable that wraps around the drum as it rotates in one direction to raise the conveyance and unwraps as the drum rotates in the other direction to lower the conveyance. Occasionally emergency situations, such as over-speed or over-travel of the conveyance, may arise which require stopping the hoist immediately. Emergency braking system are therefore included in the control systems of such hoists.
Existing emergency braking systems provide for immediate stopping of the rotating drum regardless of the speed or direction of travel of the conveyance. While these relatively simple and uncomplicated systems do stop the conveyance in emergency situations, they are undesirable in systems in which deceleration rates of the conveyance must not exceed a maximum rate. Problems with deceleration rates may arise, for example, in the hoisting or ascending mode where the effect of gravity and emergency braking occurring simultaneously may exceed maximum allowable deceleration rates.
For example, instantaneous braking of the conveyance during ascent would stop the conveyance but the upward inertia of the equipment in the conveyance could cause it to rise off the conveyance floor; then it would crash back to the floor, causing possible damage to the equipment and the conveyance.
Existing braking control systems that have proved to do an adequate job of stopping the conveyance in emergency situations within allowable deceleration limits have included relatively complex and expensive electronic circuitry to slow down and bring the conveyance to a stop according to a predetermined program of deceleration rate. This circuitry is responsive to the speed of the conveyance and causes adjustments in the speed of the drum to be made to maintain the deceleration rate of the conveyance within prescribed limits. While the use of such complex electronic circuitry can be justified in some hoists, they are often too expensive for practical use in many hoisting applications, must occasionally be calibrated and adjusted, and are subject to human error or tampering.
SUMMARY OF THE INVENTION
The present invention overcomes the drawbacks associated with the relatively complex and expensive electronic emergency braking control systems by providing a control circuit designed to take advantage of gravity in bringing the conveyance to a complete stop after an emergency situation arises before the emergency brake is applied in the hoisting mode of operation.
The control circuit of the present invention comprises a means for generating a first electrical signal indicative of the direction of travel of said conveyance which may, as in the embodiment shown, include a generator mechanically coupled to the rotating drum of the hoist. The generator has an output signal of one polarity when the drum rotates in one direction, and has an output signal of the opposite polarity when the drum rotates in the opposite direction.
There is also provided a means for generating a second electrical signal indicative of the presence or absence of an emergency situation. The second signal may be generated by one or more switches that are operated to indicate an emergency situation thereby enabling application of the emergency brake.
A control circuit means responsive to said first and second signals is connected to immediately apply the brake when said first signal is indicative of descending motion or lowering of the conveyance and said second signal indicates the presence of an emergency situation but allows application of said brake only after said conveyance has come to a complete stop when said first signal indicates ascending motion or raising of the conveyance and said second signal indicates the presence of an emergency situation.
The control circuit may also be provided with additional safety features to provide immediate application of the emergency brake regardless of the direction of travel of the conveyance to allow adequate and timely braking in the event certain emergencies exist which warrant deceleration of the conveyance at a rate outside the prescribed maximum.
The present invention will be more fully understood by reading the following description of the preferred embodiment with reference to the accompanying drawings in which:
FIG. 1 is a schematic circuit diagram of one embodiment of the control system constructed according to the principle of the present invention, and
FIG. 2 is a schematic circuit diagram of another embodiment of the control system of the present invention which incorporates certain safety features.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, a control circuit constructed according to the principles of the present invention is shown as including what will be referred to for convenience as the motor control circuit 12 and the emergency brake control circuit 14.
In the embodiment shown, a motor (not shown) which drives hydraulic pump (not shown) has a magnetic starter and auxiliary contacts 1M. The hydraulic fluid from the pump is employed to rotate the hoist drum (not shown). When power is applied to a starter, contact 1M closes applying power to first control relay 1CR to close the contacts 1CR1 and connect the remainder of the motor control circuit 12 to line voltage. If desired, a heat exchange fan motor 15 may be used. A light 16 is provided to visually indicate the presence of AC power to the control circuit. When the operator desires to commence the hoisting operation, the brake release and reset button 17 is pushed to simultaneously energize a second control relay 2CR and a first solenoid 18 that controls the flow of hydraulic fluid to the motor. The second control relay 2CR closes contacts 2CR1 to connect a series of emergency switches 19, 20, 21 and 22 to the motor control circuit 12, and also closes contact 2CR2 in the emergency brake control circuit 14 to energize a second solenoid 23 that releases the emergency brake (not shown).
The brake control circuit 14 is operated from a low voltage twelve volt DC battery 24 that is preferably connected in parallel to a floating battery charger 25 powered by an uninterruptable AC power source 26 such as a lighting circuit. A DC switch 27 may be provided to connect and disconnect the brake control circuit from the DC battery 24. A light 28 is connected to indicate the presence of DC power to the brake control circuit 14.
A voltage polarity sensitive relay 30, such as an AP1000 manufactured by Action Instruments of San Diego, Calif., is connected in parallel with the battery 24 and has input terminals 33 connected to the output of a DC tach generator 31, such as that manufactured by Zero-Max of Minneapolis, Minn. The generator 31 is mechanically coupled to the hoist drum and rotates with it, so that the polarity of the generator output is indicative of the direction of rotation of the hoist drum. The polarity shown is indicative of descending travel or lowering of the conveyance. Variable resistor 32 is provided to adjust the magnitude of the output voltage of the generator to correspond with the input voltages acceptable to the particular voltage polarity relay 30 used. In the case of the AP1000 relay, a maximum input of ±10VDC is acceptable.
The voltage polarity sensitive relay 30 includes a set of Form C contacts 34, shown in their normally open position. This relay 30 is energized when the input voltage polarity at the input terminals 33 is indicative of ascending motion or raising of the conveyance so that the contacts 34 are closed when the conveyance is being raised.
In operation, when one of the emergency switches 19, 20, 21, 22 is opened by the occurrence of a condition while the conveyance is being lowered which requires emergency braking of the hoist conveyance. The opening of the emergency switches 19, 20 21 or 22 in the motor control circuit 12 deenergizes the second control relay 2CR thereby opening contacts 2CR2 in the brake control circuit 14 to deenergize the emergency brake solenoid 23 to immediately apply the emergency brake. Because the conveyance is descending at the time the emergency signal is given, the tach generator 31 provides a voltage of the polarity shown in FIG. 1 which does not energize the voltage polarity sensitive relay 30, thereby allowing contact 2CR2 in the brake control circuit 14 to deenergize the emergency brake solenoid 23. When control relay 2CR is deenergized, the first solenoid 18 is also deenergize causing the hydraulic fluid to bypass the motor to allow rotation of the drum to be stopped by application of the emergency brake.
If an emergency situation arises while the conveyance is being raised, the open emergency switch 19, 20, 21 or, 22 deenergizes the control relay 2CR which causes its contacts 2CR1, 2CR2 to open as before; however, since the conveyance is ascending, the generator 31 produces a voltage having a polarity opposite that shown in FIG. 1 which energizes the voltage polarity sensitive relay 30 to close contacts 34. The connection through contacts 34 maintains the emergency brake solenoid 23 in an energized state so that the emergency brake is not immediately applied even though contact 2CR2 is open.
During the time interval in which the hydraulic motor is disconnected by deenergizing the solenoid 18 by opening contact 2CR1 in the motor control circuit 12, the force of gravity on the conveyance eventually brings it to a stop. Once the conveyance is stopped and the drum therefore stops rotating, the voltage generated by tach generator 31 reduces to zero to deenergize relay 30. Contacts 34 then return to their normal position to deenergize brake solenoid 23 and apply the brake.
The foregoing embodiment provides immediate application of the emergency brake if the conveyance is descending or being lowered and delayed application of the emergency brake if the conveyance is being raised. The delay allows gravity to bring the conveyance to a stop. When the mechanical components of the conveyance are properly dimensioned and designed, the rate of deceleration is normally within the acceptable maximum deceleration rates allowed in most hoisting applications. It is therefore essential that an analysis of the deceleration of the conveyance under coasting conditions when ascending be made and the mechanical components be adjusted before utilizing the control system of the present invention.
While the control circuit of the embodiment shown in FIG. 1 provides for selective application of the emergency brake in a hoist, it is sometime desirable and often preferable to provide for immediate application of the emergency brake regardless of the direction of travel of the conveyance. For example, it would be desirable to immediately apply the emergency brake even though conveyance is ascending if delayed application of the brake would allow the conveyance to over travel its present limits.
The embodiment of the present invention shown in FIG. 2 provides for such contingency. Moreover, the hydraulic fluid bypass solenoid 18 and the control relays 1CR, 2CR are connected in the battery powered 12 VDC control circuit 14 to allow control of the hoist in the event of a power failure. The embodiment of FIG. 2 which may, for example, employ for power a diesel motor, differs from that of FIG. 1 in that a timing relay TR is added to the brake control circuit 14 and the switches indicating over speed 20 and over travel 21, 22 of the conveyance are connected in series/parallel, not serially connected as in FIG. 1. The manual emergency stop button 19, the over speed limit switch 20, the instantaneous set of contacts 1TR1 of timing relay TR, and the normally open contacts 1CR1 of control relay 1CR are serially connected to the hydraulic bypass solenoid 18 that is in parallel with the timing relay TR. The over travel limit switches 21, 22 are serially connected to control relay 1CR. Footswitch 43 is also provided to bypass the over travel limit switches 21, 22 in the event hoisting or lowering must be commenced while the conveyance is in an over travel position. A practical reason for utilizing a footswitch 43 is that for total operation of an "overtravel backout" condition would otherwise require the use of three hands for each of the regular brake handle, the control to the hydraulic motor for motion, and the contact with reset button 19. Footswitch 43 replaces pushbutton 19 for this condition. An "overtravel backout" condition refers to a situation in which the conveyance has overtraveled at the top or bottom, and the operator necessarily must move the conveyance in the reverse direction.
When the manually operated emergency button 19 or the over speed limit switch 20 is opended while the conveyance is descending, the timing relay TR is deenergized to open instantaneous contacts 1TR 1, 2 thereby deenergizing the hydraulic fluid bypass solenoid 18 and control relay 2CR. Contacts 2CR1 immediately open to deenergize the emergency brake solenoid 23 and apply the emergency brake. Since the conveyance was descending, the generator 31 produced a voltage having a polarity that did not energize the relay 30, therefore its contacts 34 remained open to control relay 2CR.
If the bottom over travel limit switch 22 was opened while the conveyance was descending, control relay 1CR becomes deenergized thereby deenergizing control relay 2CR through contacts 1CR2 to deenergize the emergency brake solenoid 23 to immediately apply the brake. Again the polarity of the voltage produced by the generator 31 does not energize the relay 30.
When the conveyance is ascending and either the manually operated emergency button 19 or the over speed limit switch 20 is opened timing relay TR deenergizes thereby opening instantaneous contacts 1TR1 to deenergize the hydraulic fluid bypass solenoid 18. Since the conveyance is ascending, the polarity of the voltage of generator 31 has energized relay 30 to close its contacts 34. Control relay 2CR therefore remains energized until the force of gravity brings the conveyance to a stop thereby reversing the polarity of the generator 31 voltage to deenergize the relay 30 which in turn causes relay 2CR to deenergize and apply the emergency brake by deenergizing emergency brake solenoid 23. It will be noted that timed contacts 1TR3 provide for delayed deenergizing of control relay 2CR in the event the voltage polarity sensitive relay 30 does not function properly. The timed contacts 1TR3 can be adjusted to provide a time interval that deenergizes control relay 2CR after the voltage polarity sensitive relay 30 should have deenergized.
In the embodiment shown, if the top over travel limit switch 21 is opened while the conveyance is ascending, the emergency brake is immediately applied. This is because many situations warrant immediate braking in this emergency even though by doing so the maximum deceleration rate could be surpassed. It can be seen that opening of the top over travel limit switch 21 causes immediate application of the emergency brake as was the case when the bottom over travel limit switch 22 was opened when the conveyance was descending.
While two particular embodiments of the present have been described, it will be understood that changes and modifications, such as employing hydraulic analogs of electrical components, may be made without departing from the scope of the present invention as defined by the following claims. | An emergency brake control system for hoists including means for generating a first electrical signal indicating the direction of travel of a conveyance, means for generating a second signal indicating the presence or absence of an emergency situation and control means responsive to the first and second signals for immediately applying the emergency brake when the conveyance is descending and an emergency exists and delaying application of the emergency brake only after the conveyance has come to a complete stop when the conveyance is ascending and an emergency exists. Overriding safety features may also be employed to provide immediate application of the emergency brake regardless of the direction of travel of the conveyance of certain emergencies, such as over travel of the conveyance, exist. | 1 |
FIELD OF THE INVENTION
[0001] This invention relates to non-carbon, metal-based, anodes for use in cells for the electrowinning of aluminium from alumina dissolved in a fluoride-containing molten electrolyte, methods for their fabrication, and electrowinning cells containing such anodes and their use to produce aluminium.
BACKGROUND ART
[0002] The technology for the production of aluminium by the electrolysis of alumina, dissolved in molten cryolite, at temperatures around 950° C. is more than one hundred years old.
[0003] This process, conceived almost simultaneously by Hall and Heroult, has not evolved as many other electrochemical processes.
[0004] The anodes are still made of carbonaceous material and must be replaced every few weeks. During electrolysis the oxygen which should evolve on the anode surface combines with the carbon to form polluting CO 2 and small amounts of CO and fluorine-containing dangerous gases. The actual consumption of the anode is as much as 450 Kg/Ton of aluminium produced which is more than ⅓ higher than the theoretical amount of 333 Kg/Ton.
[0005] Using metal anodes in aluminium electrowinning cells would drastically improve the aluminium process by reducing pollution and the cost of aluminium production.
[0006] U.S. Pat. No. 4,374,050 (Ray) discloses inert anodes made of specific multiple metal compounds which are produced by mixing powders of the metals or their compounds in given ratios followed by pressing and sintering, or alternatively by plasma spraying the powders onto an anode substrate. The possibility of obtaining the specific metal compounds from an alloy containing the metals is mentioned.
[0007] U.S. Pat. No. 4,614,569 (Duruz/Derivaz/Debely/Adorian) describes non-carbon anodes for aluminium electrowinning coated with a protective coating of cerium oxyfluoride, formed in-situ in the cell or pre-applied, this coating being maintained by the addition of a cerium compound to the molten cryolite electrolyte. This made it possible to have a protection of the surface from the electrolyte attack and to a certain extent from the gaseous oxygen but not from the nascent monoatomic oxygen.
[0008] EP Patent application 0 306 100 (Nyguen/Lazouni/Doan) describes anodes composed of a chromium, nickel, cobalt and/or iron based substrate covered with an oxygen barrier layer and a ceramic coating of nickel, copper and/or manganese oxide which may be further covered with an in-situ formed protective cerium oxyfluoride layer. Likewise, U.S. Pat. Nos. 5,069,771, 4,960,494 and 4,956,068 (all Nyguen/Lazouni/Doan) disclose aluminium production anodes with an oxidised copper-nickel surface on an alloy substrate with a protective oxygen barrier layer. However, full protection of the alloy substrate was difficult to achieve.
[0009] U.S. Pat. No. 5,510,008 (Sekhar/Liu/Duruz) discloses an anode made from an inhomogeneous porous metallic body obtained by micropyretically reacting a metal powder mixture of nickel, iron, aluminium and optionally copper. The porous metal is anodically polarised in-situ to form a dense iron-rich oxide outer portion whose surface is electrochemically active. Bath materials such as cryolite which may penetrate the porous metallic body during formation of the oxide layer become sealed off from the electrolyte and from the active outer surface of the anode where electrolysis takes place, and remain inert inside the electrochemically-inactive inner metallic part of the anode.
[0010] Metal or metal-based anodes are highly desirable in aluminium electrowinning cells instead of carbon-based anodes. Many attempts were made to use metallic anodes for aluminium production, however they were never adopted by the aluminium industry for commercial aluminium production because their lifetime must still be increased.
OBJECTS OF THE INVENTION
[0011] A major object of the invention is to provide an anode for aluminium electrowinning which has no carbon so as to eliminate carbon-generated pollution and has a long life.
[0012] A further object of the invention is to provide an aluminium electrowinning anode material with a surface having a high electrochemical activity for the oxidation of oxygen ions and the formation of bimolecular gaseous oxygen and a low solubility in the electrolyte.
[0013] Another object of the invention is to provide an anode for the electrowinning of aluminium which is covered with an adherent electrochemically active layer.
[0014] Yet another object of the invention is to provide an improved anode for the electrowinning of aluminium which is made of readily available material(s).
[0015] Yet another object of the invention is to provide operating conditions for an aluminium electrowinning cell under which the contamination of the product aluminium is limited.
SUMMARY OF THE INVENTION
[0016] The invention relates to an anode of a cell for the electrowinning of aluminium from alumina dissolved in a fluoride-containing molten electrolyte. The anode comprises a nickel-iron alloy substrate having a nickel metal rich outer portion with an integral nickel-iron oxide containing surface layer which is pervious to electrolyte and adheres to the nickel metal rich outer portion of the nickel-iron alloy substrate. The electrolyte-pervious surface layer in use is electrochemically active for the evolution of oxygen gas.
[0017] Cermet anodes which have been described in the past in relation to aluminium production have an oxide content which forms the major phase of the anode. Such anodes have an overall electrical conductivity which is higher than that of solid ceramic anodes but insufficient for industrial commercial production. Moreover, the uniformly distributed metallic phase is exposed to dissolution into the electrolyte.
[0018] Conversely, anodes predominantly made of metal and protected with a thick oxide outer layer, e.g. as disclosed in U.S. Pat. No. 5,510,008 (Sekhar/Liu/Duruz), have a higher conductivity and longer life because the metal is normally shielded from the bath and resists dissolution therein. However, in case such a thick oxide layer is damaged, molten electrolyte may penetrate into cracks between the metallic inner part and the oxide layer. The surfaces of the crack would then form a dipole between the metallic inner anode part and the oxide layer, causing electrolytic dissolution of the metallic inner part into the electrolyte contained in the crack and corrosion of the metallic anode part underneath the thick oxide layer.
[0019] The anode of the present invention provides a solution to this problem. Instead of being covered with a thick protective oxide layer, during use the nickel-iron alloy substrate contacts or virtually contacts molten electrolyte circulating through the electrolyte-pervious surface layer. As opposed to prior art anodes, the electrolyte close to the nickel-iron alloy substrate, typically at a distance of less than 10 micron, is continuously replenished with dissolved alumina. The electrolysis current does not dissolve the anode. Instead the entire electrolysis current passed at the anode surface is used for the electrolysis of alumina by oxidising oxygen-containing ions directly on the active surfaces or by firstly oxidising fluorine-containing ions that subsequently react with oxygen-containing ions, as described in PCT/IB99/01976 (Duruz/de Nora).
[0020] Furthermore, the overall electrical conductivity of the metal anode according to the present invention is substantially higher than that of prior art anodes covered with a thick oxide protective layer or made of bulk oxide.
[0021] Usually, the metal phase underlying the electrochemically active surface layer of this anode forms a matrix containing a minor amount of metal compound inclusions, in particular oxide inclusion resulting from a pre-oxidation treatment in an oxidising atmosphere, which matrix confers an overall high electrical conductivity to the anode.
[0022] The electrolyte-pervious electrochemically active surface layer of the invention is usually a very thin one, preferably having a thickness of less than 50, possibly less than 100 micron or at most 200 micron.
[0023] Such a thin electrolyte-pervious electrochemically active surface layer offers the advantage of limiting the width of possible pores and/or cracks present in the surface layer to a small size, usually below about a tenth of the thickness of the surface layer. When a small pore and/or crack is filled with molten electrolyte, the electrochemical potential difference in the molten electrolyte across the pore and/or crack is below the reduction-oxidation potential of any metal oxide of the surface layer present in the molten electrolyte contained in the pore and/or crack. Therefore, such an electrolyte-pervious surface layer cannot be dissolved by electrolysis of its constituents within the pores and/or cracks. Thus, the pores and/or cracks should be so small that when the surface layer is polarised, the potential differential through each pore or crack is below the potential for electrolytic dissolution of the oxide of the surface layer.
[0024] This means that, inside the electrolyte-pervious surface layer, no or substantially no oxide of the surface layer should be able to dissolve electrolytically when the surface layer is polarised. For instance, the thinness of the oxide surface layer is such that, when polarised during use, the voltage drop therethrough is below the potential for electrolytic dissolution of the oxide of the surface layer.
[0025] Another advantage which is derived from a thin electrochemically active and electrolyte-pervious surface layer can be observed when electrolyte contained in pores and/or cracks of the surface layer reaches the nickel metal rich outer portion of the nickel-iron alloy. When this happens, the thinness of the surface layer permits oxygen evolved on the surface layer to reach the nickel metal rich outer portion, which leads to the formation of a passive layer of nickel oxide on the nickel metal rich outer portion where contacted by molten electrolyte, avoiding the dissolution of nickel cations from the nickel metal rich outer portion into the molten electrolyte.
[0026] Before use, the anode can have a Ni/Fe atomic ratio below 1 or of at least 1, in particular from 1 to 4.
[0027] The nickel metal rich outer portion may have a porosity obtainable by oxidation in an oxidising atmosphere before use. This porosity may contain cavities, in particular round or elongated cavities, which are partly or completely filled with iron compounds, in particular oxides resulting from an oxidation treatment in an oxidising atmosphere, and possibly also nickel compounds, such as nickel oxides or iron-nickel oxides, to form inclusions of iron compounds or iron and nickel compounds.
[0028] The inclusions may be iron-rich nickel-iron oxides, typically containing oxidised iron and oxidised nickel in an Fe/Ni atomic ratio above 2.
[0029] Usually the nickel metal rich outer portion has a decreasing concentration of iron metal towards the electrochemically active surface layer. The nickel metal rich outer portion, where it reaches the surface layer, may comprise nickel metal and iron metal in an Ni/Fe atomic ratio of about 3 or more.
[0030] The nickel-iron alloy may further comprise a nonporous inner portion which is oxide-free.
[0031] The electrochemically active surface layer usually comprises iron-rich nickel-iron oxide, such as nickel-ferrite, in particular non-stoichiometric nickel-ferrite. For instance, the surface layer may comprise nickel-ferrite having an excess of iron or nickel and/or an oxygen-deficiency.
[0032] The nickel-iron alloy usually comprises nickel metal and iron metal in a total amount of at least 65 weight %, usually at least 80, 90 or 95 weight %, of the alloy, and further alloying metals in an amount of up to 35 weight %, in particular up to 5, 10 or 20 weight %, of the alloy. Minor amounts of further elements, such as carbon, boron, sulphur, phosphorus or nitrogen, may be present in the nickel-iron alloy, usually in a total amount which does not exceed 2 weight % of the alloy.
[0033] For example, the nickel-iron alloy can comprise at least one further metal selected from chromium, copper, cobalt, silicon, titanium, tantalum, tungsten, vanadium, zirconium, yttrium, molybdenum, manganese and niobium in a total amount of up to 5 or 10 weight % of the alloy. The nickel-iron alloy may also comprise at least one catalyst selected from iridium, palladium, platinum, rhodium, ruthenium, tin or zinc metals, Mischmetals and their oxides and metals of the Lanthanide series and their oxides as well as mixtures and compounds thereof, in a total amount of up to 5 weight % of the alloy. Furthermore, the nickel-iron alloy may comprise aluminium in an amount less than 20 weight %, in particular less than 10 weight %, preferably from 1 to 5 or even 6 weight % of the alloy. The aluminium may form an intermetallic compound with nickel which is known to be mechanically and chemically well resistant.
[0034] The anode of the invention may comprise an inner core made of an electronically conductive material, such as metals, alloys, intermetallics, cermets and conductive ceramics, which core is covered with the nickel-iron alloy substrate as a layer. In particular, the core may comprise at least one metal selected from copper, chromium, nickel, cobalt, iron, aluminium, hafnium, molybdenum, niobium, silicon, tantalum, tungsten, vanadium, yttrium and zirconium, and combinations and compounds thereof. For instance, the core may consist of an alloy comprising 10 to 30 weight % of chromium, 55 to 90 weight % of at least one of nickel, cobalt and/or iron and up to 15 weight % of at least one of aluminium, hafnium, molybdenum, niobium, silicon, tantalum, tungsten, vanadium, yttrium and zirconium.
[0035] In one embodiment, the core is a non-porous nickel rich nickel-iron alloy, having a nickel/iron weight ratio that is close to or higher than the nickel/iron weight ratio of the nickel-iron alloy substrate, for example from 1 to 4 or higher, in particular above 3. Thus, during use, little or no iron diffuses from the inner core.
[0036] Another aspect of the invention relates to a method of manufacturing an anode as described above. The method comprises providing a nickel-iron alloy substrate and oxidising the nickel-iron alloy substrate to produce the electrolyte-pervious electrochemically active nickel-iron oxide containing surface layer which adheres to the nickel metal rich outer portion. The oxidation of the nickel-iron alloy substrate comprises one or more steps at a temperature of 800° to 1200° C., in particular 1050° to 1150° C., for up to 60 hours in an oxidising atmosphere.
[0037] Preferably, the nickel-iron alloy substrate is oxidised in an oxidising atmosphere for a short period of time, such as 0.5 to 5 hours.
[0038] The oxidising atmosphere may consist of oxygen or a mixture of oxygen and one or more inert gases, such as argon, having an oxygen content of at least 10 molar % of the mixture. Conveniently, the oxidising atmosphere can be air.
[0039] In order to obtain a microstructure of the nickel-iron alloy substrate giving upon oxidation an optimal electrochemically active surface layer on an optimal nickel metal rich outer portion, the nickel-iron alloy substrate may be subjected to a thermal-mechanical treatment for modifying its microstructure before oxidation. Alternatively, it may be cast, before oxidation, with known casting additives.
[0040] Furthermore, the oxidation of the nickel-iron alloy substrate in an oxidising atmosphere may be followed by a heat treatment in an inert atmosphere at a temperature of 800° to 1200° C. for up to 60 hours. When oxidation in an oxidising atmosphere is partial, it may be completed by oxidation in-situ at the beginning of electrolysis.
[0041] As mentioned above, the nickel-iron alloy substrate may be formed as a layer on an inner core made of an electronically conductive material, such as a nickel-rich nickel-iron alloy core. Nickel and iron metal may be deposited as such onto the core, or compounds of nickel and iron may be deposited on the core and then reduced, for example one or more layers of Fe(OH) 2 and Ni(OH) 2 are deposited onto the core, e.g. as a colloidal slurry, and reduced in a hydrogen atmosphere. Nickel and iron and/or compounds thereof may be co-deposited onto the inner core or deposited separately in different layers which are then interdiffused, e.g. by heat treatment. This heat treatment may take place in an inert atmosphere, such as argon, if the nickel and iron are applied as metals, or a reducing atmosphere, such as hydrogen, if nickel and iron compounds are applied onto the core. The nickel and iron metals and/or compounds may be deposited by electrolytic or chemical deposition, arc or plasma spraying, painting, dipping or spraying.
[0042] A further aspect of the invention concerns a cell for the electrowinning of aluminium from alumina dissolved in a fluoride-containing molten electrolyte. The cell according to the invention comprises at least one anode as described above which faces and is spaced from at least one cathode.
[0043] The invention also relates to a method of producing aluminium in such a cell. The method comprises passing an ionic current in the molten electrolyte between the cathode(s) and the electrochemically active surface layer of the anode(s), thereby evolving at the anode(s) oxygen gas derived from the dissolved alumina and producing aluminium on the cathode(s).
[0044] At the beginning of electrolysis, the nickel metal rich outer portion of the anode(s) may be further oxidised in-situ by atomic and/or molecular oxygen formed on its electrochemically active surface layer, in particular if the anode comprises a surface which is partly oxide-free when immersed into the molten electrolyte, until the oxidised nickel metal rich outer portion of the anode forms an impervious barrier to oxygen.
[0045] Advantageously, the method includes substantially saturating the molten electrolyte with alumina and species of at least one major metal, usually iron and/or nickel, present in the electrochemically active surface layer of the anode(s) to inhibit dissolution of the anode(s). The molten electrolyte may be operated at a temperature sufficiently low to limit the solubility of the major metal species thereby limiting the contamination of the product aluminium to an acceptable level.
[0046] A “major metal” refers to a metal which is present in the surface of the metal-based anode, in an amount of at least 25 atomic % of the total amount of metal present in the surface of the metal based anode.
[0047] The cell can be operated with the molten electrolyte at a temperature from 730° to 910° C., in particular below 870° C.
[0048] As disclosed in PCT/IB99/01976 (Duruz/de Nora), the electrolyte may contain AlF 3 in such a high concentration that fluorine-containing ions predominantly rather than oxygen ions are oxidised on the electrochemically active surface, however, only oxygen is evolved, the evolved oxygen being derived from the dissolved alumina present near the electrochemically active anode surface.
[0049] Preferably, aluminium is produced on an aluminium-wettable cathode, in particular on a drained cathode, for instance as disclosed in U.S. Pat. No. 5,683,559 (de Nora) or in PCT application WO99/02764 (de Nora/Duruz).
[0050] In a modification, the nickel of the nickel-iron alloy, in particular of the integral oxide containing surface layer, is wholly or predominantly substituted by cobalt.
DETAILED DESCRIPTION
[0051] The invention will be further described in the following Examples:
EXAMPLE 1
[0052] An anode was made by pre-oxidising in air at 1100° C. for 1 hour a substrate of a nickel-iron alloy consisting of 60 weight % nickel and 40 weight % iron, to form a very thin oxide surface layer on the alloy.
[0053] The surface-oxidised anode was cut perpendicularly to the anode operative surface and the resulting section of the anode was subjected to microscopic examination.
[0054] The anode before use had an outer portion that comprised an electrolyte-pervious, electrochemically active iron-rich nickel-iron oxide surface layer having a thickness of up to 10-20 micron and, underneath, an iron-depleted nickel-iron alloy having a thickness of about 10-15 micron containing generally round cavities filled with iron-rich nickel-iron oxide inclusions and having a diameter of about 2 to 5 micron. The nickel-iron alloy of the outer portion contained about 75 weight % nickel.
[0055] Underneath the outer portion, the nickel-iron alloy had remained substantially unchanged.
EXAMPLE 2
[0056] An anode prepared as in Example 1 was tested in an aluminium electrowinning cell containing a molten electrolyte at 870° C. consisting essentially of NaF and AlF 3 in a weight ratio NaF/AlF 3 of about 0.7 to 0.8, i.e. an excess of AlF 3 in addition to cryolite of about 26 to 30 weight % of the electrolyte, and approximately 3 weight % alumina. The alumina concentration was maintained at a substantially constant level throughout the test by adding alumina at a rate adjusted to compensate the cathodic aluminium reduction. The test was run at a current density of about 0.6 A/cm 2 , and the electrical potential of the anode remained substantially constant at 4.2 volts throughout the test.
[0057] During electrolysis aluminium was cathodically produced while oxygen was anodically evolved which was derived from the dissolved alumina present near the anodes.
[0058] After 72 hours, electrolysis was interrupted and the anode was extracted from the cell. The external dimensions of the anode had remained unchanged during the test and the anode showed no signs of damage.
[0059] The anode was cut perpendicularly to the anode operative surface and the resulting section of the used anode was subjected to microscopic examination, as in Example 1.
[0060] It was observed that the anode had an electrochemically active surface covered with a discontinuous, non-adherent, macroporous iron oxide external layer of the order of 100 to 500 micron thick, hereinafter called the “excess iron oxide layer”. The excess iron oxide layer was pervious to and contained molten electrolyte, indicating that it had been formed during electrolysis.
[0061] The excess iron oxide layer resulted from the excess of iron contained in the portion of the nickel-iron alloy underlying the electrochemically active surface and which diffuses therethrough. In other words, the excess iron oxide layer resulted from an iron migration from inside to outside the anode during the beginning of electrolysis.
[0062] Such an excess iron oxide layer has no or little electrochemical activity. It slowly diffuses and dissolves into the electrolyte until the portion of the anode underlying the electrochemically active surface reaches an iron content of about 15-20 weight % corresponding to an equilibrium under the operating conditions at which iron ceases to diffuse, and thereafter the iron oxide layer continues to dissolve into the electrolyte.
[0063] The anode's aforementioned outer portion had been transformed during electrolysis. Its thickness had grown from 10-20 micron to about 300 to 500 micron and the cavities had also grown in size to vermicular form but were only partly filled with iron and nickel compounds. No electrolyte was detected in the cavities and no sign of corrosion appeared throughout the anode.
[0064] The absence of any corrosion demonstrated that the pores and/or cracks in the electrolyte-pervious electrochemically active oxide layer were sufficiently small that, when polarised during use, the voltage drop through the pores and/or cracks was below the potential of electrolytic dissolution of the oxide of the surface layer.
[0065] Underneath the outer portion, the nickel-iron alloy had remained unchanged.
[0066] The shape and external dimensions of the anode had remained unchanged after electrolysis which demonstrated stability of this anode structure under the operating conditions in the molten electrolyte.
[0067] In another test a similar anode was operated under the same conditions for several hundred hours at a substantially constant current and cell voltage which demonstrated the long anode life compared to known noncarbon anodes.
EXAMPLE 3
[0068] An anode having a generally circular active structure of 210 mm outer diameter was made of three concentric rings spaced from one another by gaps of 6 mm. The rings had a generally triangular cross-section with a base of about 19 mm and were connected to one another and to a central vertical current supply rod by six members extending radially from the vertical rod and equally spaced apart from one another around the vertical rod. The gaps were covered with chimneys for guiding the escape of anodically evolved gas to promote the circulation of electrolyte and enhance the dissolution of alumina in the electrolyte as disclosed in PCT publication WO00/40781 (de Nora).
[0069] The anode and the chimneys were made from cast nickel-iron alloy containing 50 weight % nickel and 50 weight % iron that was heat treated as in Example 1. The anode was then tested in a laboratory scale cell containing an electrolyte as described in Example 2 except that it contained approximately 4 weight % alumina.
[0070] During the test, a current of approximately 280 A was passed through the anode at an apparent current density of about 0.8 A/cm 2 on the apparent surface of the anode. The electrical potential of the anode remained substantially constant at approximately 4.2 volts throughout the test.
[0071] The electrolyte was periodically replenished with alumina to maintain the alumina content in the electrolyte close to saturation. Every 100 seconds an amount of about 5 g of fine alumina powder was fed to the electrolyte. The alumina feed was periodically adjusted to the alumina consumption based on the cathode efficiency, which was about 67%.
[0072] As in Examples 2, during electrolysis aluminium was cathodically produced while oxygen was anodically evolved which was derived from the dissolved alumina present near the anodes.
[0073] After more than 1000 hours, i.e. 42 days, electrolysis was interrupted and the anode was extracted from the cell and allowed to cool. The external dimensions of the anode had not been substantially modified during the test but the anode was covered with iron-rich oxide and bath. The anode showed no sign of damage.
[0074] The anode was cut perpendicularly to the anode operative surface and the resulting section of a ring of the active structure was subjected to microscopic examination, as in Example 1.
[0075] It was observed that the porous outer alloy portion had grown inside the anode ring to a depth of about 7 mm leaving only an inner portion of about 5 mm diameter unchanged, i.e. consisting of a non-porous alloy of 50 weight % nickel and 50 weight % iron. The porous outer portion of the anode had a concentration of nickel varying from 85 to 90 weight % at the anode surface to 70 to 75 weight % nickel close to the non-porous inner portion, the balance being iron. The iron depletion in the openly porous outer portion corresponded about to the accumulation of iron present as oxide on the surface of the anode, which indicated that the iron oxide had not substantially dissolved into the electrolyte during the test.
[0076] As in the previous Example, the anode showed no sign of corrosion which demonstrated that the pores and/or cracks in the electrolyte-pervious electrochemically active oxide layer were sufficiently small that, when polarised during use, the voltage drop through the pores and/or cracks was below the potential of electrolytic dissolution of the oxide of the surface layer. | An anode of a cell for the electrowinning of aluminium comprises a nickel-iron alloy substrate having a nickel metal rich outer portion with an electrolyte pervious integral nickel-iron oxide containing surface layer which adheres to the nickel metal rich outer portion of the nickel-iron alloy and which in use is electrochemically active for the evolution of oxygen. The oxide surface layer has a thickness such that, during use, the voltage drop therethrough is below the potential of dissolution of nickel-iron oxide. The nickel metal rich outer portion may contain cavities some or all of which, after oxidation, are partly or completely filled with iron oxides to form iron oxide containing inclusions. | 2 |
BACKGROUND OF THE INVENTION
The invention relates to a fuel injection pump for an internal combustion engine, having a cam drive effecting the delivery movement of at least one fuel pump piston.
In a known fuel injection pump, by means which function independently of each other, an increased fuel quantity during starting, an idling rpm, and not least an rpm-dependent adjustment of injection are attained. However, Diesel engine manufacturers increasingly require an intervention to be made into the regulation process of the injection pump in accordance with the engine temperature. It is already known, for instance, to vary the zero or rest position of the adjustment lever of the injection pump via an expansion-element regulator and a Bowden cable to attain a decrease in the idling rpm, as the engine temperature increases. It is also known to control the adjustment piston of a hydraulic injection adjuster toward "early" during cold starting, via a thermostat. It is further known to reduce the increased starting quantity via a thermostat when the starting temperature is increasing. All of these interventions taken singly are clearly understandable and therefore, when taken singly, attain their respective objects. In many cases, however, the application of only one of these known means is insufficient, yet the use of more than one would make the injection pump too large because of the required attachments and too expensive because of the many additional elements required for proper operation thereof. In addition, there is still the problem of adapting the various control values to one another because of the various transducers and converters.
OBJECT AND SUMMARY OF THE INVENTION
It is an object of the invention to provide a fuel injection pump in which several temperature-related interventions in the injection pump regulation can be made in the simplest manner, with an assured and simple adaptation of the individual control values to one another.
It is a further object of the invention to provide a basic fuel injection pump apparatus having the capacity for several kinds of regulation intervention which can be inexpensively mass produced, so that the engine manufacturer to whom the pump is delivered can, as needed, utilize one or all of the possible kinds of regulation intervention. In many cases, an engine which is especially equipped, such as one with turbo-charging, can thus be equipped with the same basic type of injection pump as can the same standard engine type.
The fuel injection pump, according to the invention, includes a final control device which is controllable by engine temperature, and which simultaneously adjusts at least two of three control elements influencing the injection. This final control device may be used to simultaneously adjust a first element for attaining an early injection onset when the engine is cold, and/or a second element for decreasing the starting fuel quantity as temperature increases, and/or a third element for reducing the idling rpm as temperature increases.
In the dependent claim, various embodiments and improvements of the invention as given in the main claim are disclosed.
The invention will be better understood as well as further objects and advantages thereof become more apparent from the ensuing detailed description of the preferred embodiments taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a fuel injection pump to which the invention has been applied;
FIG. 2 is a fragmentary sectional view through the pump taken along the line II--II of FIG. 1;
FIG. 3 shows a sectional view of a transducer projecting into the block of an engine and arranged to detect the engine temperature;
FIGS. 4 and 5 show final control elements for control of idling and of increased starting quantity, and
FIGS. 6 and 7 show final control elements for control of injection onset, idling, and increased starting quantity, as well as a thermostatic control apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to the fuel injection pump shown in FIG. 1, a sleeve 2 is disposed in a housing 1 and has a central blind bore 3, in which a pump piston 4 performs a simultaneously reciprocating and rotating movement. The pump work chamber 5 formed in the blind bore 3 is supplied with fuel during the suction stroke of the pump piston 4 via an intake bore 6 from the intake chamber 7 disposed in the pump housing 1 and is arranged to pump the fuel during the compression stroke via lines 8, of which only one is shown, to the fuel injection nozzles located on the internal combustion engine. A central bore 9 in the pump piston 4 and a longitudinal distributor groove 10 on the jacket surface of the pump piston 4 serve to supply fuel and distribute it to the pressure lines 8.
The pump piston 4 is driven via a cam drive 11, which has a cam ring 13, bearing rollers 12 and a disc 14 with cams on one face which are arranged to run on the rollers 12. The cam disc 14 and the pump piston are coupled with the drive shaft 15 via a rotary coupling (not shown). The cam ring 13 supported within the housing 1 is rotatable over several angular degrees via a piston injection adjuster 16 in order to adjust the beginning of injection. The stroke drive of the pump piston 4 is accomplished against the force of a restoring spring 17.
The intake chamber 7 disposed in the housing 1 and the injection adjuster 16 are supplied with fuel by means of a fuel supply pump 18. The fuel pressure is controlled in accordance with rpm and effects a corresponding adjustment of the hydraulic piston of the injection adjuster 16.
An annular slide 20 disposed about the piston 4 which controls the discharges of a transverse bore 21 of the longitudinal bore 9 in the pump piston 4 serves to control the injection quantity. The higher the control slide 20 is disposed, the later the transverse bore 21 is opened; that is, the greater is the injection quantity, and vice versa. The control slide 20 is displaced by means of a mechanical rpm governor 23. The rpm governor 23 has a starting lever 24 supported at M1, which is directly engaged by the adjustment sleeve 25 of a centrifugal adjuster which works by means of flyweights 26. The centrifugal adjuster is driven via a gear drive 27. The starting lever 24 is supported via a relatively soft starting spring 28 on a tension lever 29, which is also supported at M1 and is driven, upon a corresponding stroke of the adjustment sleeve 25, by the starting lever 24 in the manner of a drag member. However, as soon as the starting lever 24 contacts the tension lever 29, stress is placed first on an idling spring 30 and thereafter on a control spring 31. In the order of their becoming effective, the springs 28, 30, 31 are disposed in series one after the other. Because the idling spring 30 is softer than the control spring 31, the lower suspension point 32 of the control spring 31 determines the prestressing of the idling spring 30 when the tension lever 29 is in the position of rest corresponding to idling; this position of rest is determined by a stop 33. The prestressing in turn of the control spring 31 is determined by an adjustment lever 32, which is actuated by the driver and, depending on its position, causes a variation in the ratio of the injection quantity to the rpm.
Further engaging the starting lever 24 is the shutoff lever 35, through which, with a corresponding displacement, the starting lever 24 and tension lever 29 are rotated into a position for which the control slide 20 is slid downward to such an extent that no further injection can take place. This lever 35 furthermore represents a stop for the largest possible increased starting quantity. With a small amount of rotation of the shutoff lever 35, the starting position of the control slide 20 varies accordingly and thus so does the increased starting quantity vary. Should an increased starting quantity not be desirable, for instance in the event that the engine is warm, then, upon starting, the starting lever 24 is displaced directly against the tension lever 29 by means of the lever 35, so that no increased starting quantity is delivered to the engine.
In order to be able to control idling or the increased starting quantity, respectively, in accordance with the engine temperature, it is sufficient to vary the initial position of the shutoff lever 35 or the starting lever 24 in the one case, or to vary the suspension point 32 or the initial position of the adjustment lever 34 in the second case, by means of a stop which functions in accordance with temperature. At the shutoff lever 35, the possible length of the lever travel path is reduced with increasing temperature; in the case of the adjustment lever 34, the path length is increased with increasing temperature. The purpose of the latter is to attain greater relief with increasing temperature when the idling spring 30 is in the zero position. As a result of the relief, the shutoff rpm in idling is set at a lower rpm level.
In FIG. 2, the cam drive of the pump is shown along the line II--II of FIG. 1. The cam ring 13 with the rollers 12 is rotated by means of the hydraulic injection adjustment piston 16 in the housing 1 via a stub shaft 37. However, an eccentric member 39 of an adjustment device 40 also engages a groove 38 of the cam ring 13. As a result, particularly in the event of a cold start, the cam ring 13 can be adjusted automatically toward early injection. However, it is as equally well conceivable that an early adjustment should directly engage the adjustment piston 16 of the injection adjuster and displace it toward "early" in the case of the cold engine. This early adjustment is advantageously attained via a thermostat, or some comparable temperature-dependent adjustment device. Naturally it is also conceivable that this early adjustment should take place via the control means of the hydraulic pressure which is exerted upon the piston 16. What is decisive is that the rotation of the cam ring 13 toward "early" is derived from a temperature transducer, which effects the identical adjustment proportion at the governor for the purpose of variation of the increased starting quantity or the idling rpm.
In FIG. 3 there is shown a transducer 42 disposed on the engine supplied by the fuel injection pump. This transducer, embodied as a so-called expension-element regulator, projects into a chamber 43 provided in the block of the engine which has coolant flowing through it. This expansion-element regulator 42, with increasing temperature, progressively displaces a piston 45 via a tang 44, against the force of a spring 46. Two Bowden cables 47 are secured on a member that is in abutting relation with the piston 45, so that a synchronous or simultaneous triggering can take place of the backing-off movement of the shutoff lever 35 and adjustment lever 34, or of the early adjustment of the injection adjuster. Naturally, it is also possible that only two of the above interventions should be performed via this temperature transducer. However, in accordance with the invention, the pump can also be triggered by means of a transducer via only a single Bowden cable, in which case at least two and possibly all three of the control interventions described can be accomplished.
An example of such an embodiment having only one Bowden cable is shown in FIGS. 4 and 5 which are views taken at 90° one relative to the other. The pump itself is visible only in broken lines. The end of a Bowden cable 48 which extends toward the pump, the other end of which is connected to the temperature transducer on the engine, is secured via an angle bracket 49 to the pump. The cable 50 of the Bowden cable is inserted through the eye of a guide bolt 51 and secured on its end by a clamp screw 52. In the intervening portion where the cable extends freely, a further fastening screw 53 is provided which serves as a stop which determines or varies the initial position of the shutoff lever 35.
The fixing screw 52, in contrast, acts upon the bolt 51, which is axially displaceable, against the force of a spring 55, in an angle bracket 54 secured on the pump housing. Located on this bolt 51 is a stop plate 56, which extends or restricts the path of the adjustment lever 34. As a result, there is a simultaneous intervention into the control of idling and of increased starting quantity. Via the second Bowden cable of FIG. 3, which is simultaneously actuated, an intervention can be made in corresponding fashion into the adjustment of fuel injection. However, it is also entirely possible to preclude the intervention into the starting quantity, for example, by means of displacement of the stop screw 53.
In the second exemplary embodiment shown in FIGS. 6 and 7, the thermostatic transducer 58, which may be embodied fundamentally like that of FIG. 3, is disposed directly on the fuel injection pump. A sheet-metal clamp 59 accomplishes this purpose. The coolant of the engine is delivered via conduit (not shown) and nipples 60 to a chamber 61, into which the expansion-element regulator projects. The expansion-element regulator, either directly or via a Bowden cable as in the previous example, actuates a fastening member 62, which acts upon a lever 63, which in turn engages the cam ring 13, either via the eccentric 40 as in FIG. 2 or as already mentioned by means of adjustment of the hydraulic piston 16 of the injection adjuster. In each case, a shaft 64 is rotated to this end by means of the lever 63. Disposed in the extension of the lever 63 is an angularly bent strip of metal 65, which in turn supports a ball head 66 which acts as a stop for the adjustment lever 34. The full-line illustrated position applies to the warm engine; when the engine is cold, the ball head 66 assumes the position illustrated in broken lines. On the side of the lever 63 remote from the shaft 64, there is a coupler strip 67, which is coupled via a rod 68 with the shutoff lever 35 in the manner of a drag member, so that when the engine is cold, the lever path is longer than it is in the illustrated position.
Naturally, an electromagnetic transducer, which is triggered via a temperature measurement transducer, can also be used.
The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other embodiments and variants thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims. | The invention relates to a fuel injection pump in which, via an appropriate transducer, the temperature of the coolant of the internal combustion engine intervenes as a control value in the fuel injection pump regulation, in that at least two of the following three final control elements are simultaneously adjusted: A for the injection onset adjustment; B for the increased starting quantity; or C for the idling rpm. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an encasing film for a galvanic element, an electrochemical store, an electrochemical storage system, a flexible film for an encasing of a galvanic element, and a method for determining a state variable of an electrochemical store.
2. Description of the Related Art
With greater and greater demand for alternative drive concepts, the electric drive is increasingly becoming the focus of consideration. For this purpose, lithium-ion batteries are developing into the key technology for modern automobile drives. Lithium-ion cells exist in various structural forms or cell types. One particular specific embodiment is formed here by so-called pouch cells or coffee bag cells. As is already obvious from the name, pouch cells are not dimensionally stable; the cell winding thereof is welded into a flexible “film bag.”
The flexible housing used represents several system-related challenges, however. The sealing seam of the cells must thus be leak-tight over the entire service life of the battery. This is made more difficult because the cells “breathe” during the cycling, i.e., their thickness varies as a function of the state of charge. In addition, a changing pressure difference exists between the cell interior and surroundings as a result of air pressure variations and the respiration of the cell. Furthermore, aging processes, which are expressed in degassing, for example, may result in inflation of the pouch cell. The significant weight advantage, the possible stacking, which is spatially very efficient, and the large aspect ratio, whereby heat may be dissipated outward very well, are thus to be considered to be safety-critical because of the possible inflation of the cell in the event of gas development. The sealing seams of the cell may thus open nonspecifically in the event of malfunctions and overpressure resulting therefrom in the cell interior. In the worst case, combustible gases such as electrolyte or decomposition products may reach the outside, which may result in fires or explosions under certain circumstances. To monitor this safety-critical state, sensors for pouch cells are of great significance.
BRIEF SUMMARY OF THE INVENTION
Against this background, the present invention provides an encasing film for a galvanic element, an electrochemical store, an electrochemical storage system, a flexible film for an encasing of a galvanic element, and a method for determining a state variable of an electrochemical store.
A film is provided which is functionalized for a meteorological detection of a physical variable of a pouch cell, for example, a mechanical tension, a gas pressure, a cell temperature, etc. For this purpose, the film may be designed as a sensor, in particular a force sensor, or may have a sensor and may form a part of an encasing of the pouch cell or may be applicable to an outer side or inner side of the encasing of the pouch cell. One or more of the detected measured variables may be used in a corresponding method according to the present invention, for example, for a calculation of the state of charge (SOC) and/or a state of health (SOH) of the cell, and optionally additionally for a safety-relevant check of a hermetic seal (leak-tightness) of the cell.
By detecting the pressure conditions or mechanical deformation of the relatively sensitive pouch cell, a direct statement is possible about the state of charge of the battery, its state of health, and about a presence of a defect, for example, extreme pressure increase or deformation, or leaks. Thus, for example, in regard to the occupant protection, a replacement of pouch cells is possible at any time, for example, when a specific gas pressure in the cell is exceeded. With the approach provided here, the internal pressure measurement or gas pressure measurement of the pouch cell may also be read out in the uninstalled state of the battery, whereby safer recycling of the cells may be made possible. The detection, which is implementable according to the concept provided here, of the mechanical deformation of the cell on the outer side, has the additional advantage that the sensor is not exposed to the electrolyte and therefore does not have to be separately protected. In this way, the packaging of this sensor may be significantly simplified. Furthermore, the sensor and its supply lines may be integrated directly in a manufacturing process of the pouch cells. The sensor or force sensor according to the present invention is distinguished by a very small installation height and therefore does not obstruct the sequence of the cell chemistry in the pouch cell or the deformation of the external encasing. Since the supply lines may also be printed on, the sensor in this special specific embodiment does not require an additional bonding process, as is the case in conventional sensors. Because of the detection of the pressure conditions, rapid charging and discharging of the battery cells, which may be monitored, is also possible.
If the force sensor is used as a gas pressure sensor in the case of the encasing film provided here, a possible opening of the pouch cell—i.e., damage with gas pressure loss—may also be detected as a result of a delamination, for example.
Advantageously, efficient and extremely cost-effective measurement of mechanical tensions, pressures, or forces, the pH value, a half-cell voltage, and/or temperature influences in or on pouch cells is enabled by functionalizing already existing layers, introducing additional functionalized films, or printing the inner or outer encasing of the pouch cell. The measurement may be achieved via the force sensor, which may have a strain gauge, for example. In the case of the temperature measurement in the pouch cell, for a more precise measurement result, measurements may be performed locally or multiple measurements may be performed using a divided film array in the cell. An encasing film for a galvanic element is characterized in that the encasing film has at least one force sensor for detecting a strain state of the encasing film.
The encasing film may be produced from an elastic and electrically insulating material, for example, from a suitable plastic. The encasing film may be designed, for example, as a rectangular bag, which is open on one side for the insertion of the galvanic element into the encasing film. After the insertion of the galvanic element, the open side of the bag may be closed in such a way that the galvanic element is enclosed fluid-tight, in particular gas-tight, by the encasing film. A force sensor may be understood as a force pickup or a measuring unit for detecting expanding deformations. The force sensor may be elastically deformable like the encasing film and may be designed, for example, to detect a tensile force exerted on a measurement area of the force sensor. The force sensor may be fixedly connected to at least one partial area of the encasing film. Because of the fixed connection, the force sensor may also expand with an expansion of the encasing film, so that based on the detected tensile force on the force sensor, which is linked to the expansion, a degree of the expansion and therefore an expansion state of the encasing film may be inferred. The expansion of the encasing film may be attributed to chemical and/or physical processes in an electrolyte of the galvanic element enclosed by the encasing film. For example, an intercalation of the lithium in the electrodes may result in an expansion and a state of charge of the galvanic element may be determined accordingly with the aid of SOC detection, or gas development may occur in the electrolyte as a result of aging processes, whereby the encasing film inflates and expands, since the gases may not escape outward because of the fluid-tightness of the encasing film.
According to one specific embodiment, the force sensor may have a strain gauge. The strain gauge may be distinguished in that it already changes its electrical resistance in the event of slight deformations. An expansion of the encasing film may thus advantageously be detected with low cost outlay and particularly rapidly and reliably.
In particular, the force sensor may be situated on a surface of the encasing film. The force sensor may be located on an outer side or on an inner side of the bag formed by the encasing film for the galvanic element. The position of the force sensor may thus be adapted in a simple way to specification requirements. The force sensor may thus be protected from damage, for example, by an arrangement on the inner side of the encasing film. In contrast, with the arrangement on the outer side, a contact of the sensor with the electrolyte may be avoided and therefore possible ignition of the electrolyte may be prevented. The fact that only materials may be introduced into the cell which do not influence the cell chemistry does not have to be taken into account here, which has the advantage of freer material selection.
According to one specific embodiment, the force sensor may be situated in a middle area of the encasing film. The term “middle area” means in this case the middle area of the top view surface, i.e., the surface having the largest extension, the force sensor not necessarily being situated on the encasing film, but rather also being able to be situated in a perpendicular direction thereto in the interior. Alternatively or additionally, a further force sensor may be situated in an edge area of the encasing film. Edge area means in this case the area enclosing the middle area of the encasing film viewed from above. The edge area may be designed as a feedthrough area for at least one electrical contact of a galvanic element. Relevant items of information about various states of the galvanic element may thus be obtained in a simple way, specifically by suitable placement of the force sensor or further force sensor. If the galvanic element is, for example, part of a battery pack having galvanic elements lying closely against one another, with the arrangement of the force sensor in the middle area of the main side of the encasing film, so-called respiration of the cell and therefore an alternately occurring expansion and relaxation of the encasing film may thus be detected, which enables inferences about a state of charge of the galvanic element. In contrast, the arrangement of the further force sensor in the edge area, for example, close to the insertion opening of the bag formed by the encasing film, enables a measurement of a state of aging or state of health of the galvanic element, since here, where the pressure of adjacent cells does not have an effect on the encasing film, a detected expansion may indicate aging-related degassing processes of the electrolyte. Therefore, using identical sensors, which are only situated at different points of the encasing film enclosing the galvanic element, different states of the galvanic element may be monitored.
Furthermore, the encasing film may have an intended breakpoint, an electrical contact for an electrical connection of the force sensor being able to be situated in an area of the intended breakpoint. Depending on the arrangement of the force sensor on the inner side or outer side of the encasing film, the intended breakpoint may form a feedthrough area for the electrical contact of the sensor from the inside to the outside, or the electrical contact may be led on the outside past the intended breakpoint. In both cases, bursting of the intended breakpoint caused by an expansion of the encasing film causes tearing of the contact. For example, the intended breakpoint may be situated in the area of the insertion opening for the galvanic element of the encasing film forming a bag, through which, for example, further contacts for the electrical connection of the galvanic element itself may be led. With this specific embodiment, an additional possibility opens up for detecting the state of the galvanic element in that, for example, due to the tearing of the sensor contact at the intended breakpoint, a warning signal may be output about a hazardous state of the galvanic element to a connected safety system.
An electrochemical store for converting chemical energy into electrical energy has the following features:
a galvanic element;
an encasing film according to one of the above-explained specific embodiments, the encasing film enclosing the galvanic element, and the expansion state of the encasing film representing a state variable of the galvanic element.
For the electrical connection of the galvanic element, the electrochemical store may furthermore have two contacts, one of which may be embodied as an anode and the other of which may be embodied as a cathode. The galvanic element may be a lithium-ion cell, for example. The galvanic element may be part of a so-called coffee bag cell or pouch cell, which is characterized in that it is not dimensionally stable, i.e., it has a flexible jacket with the encasing film. In this specific embodiment, the cell receives a lower weight and may be used in a more space-saving way, but requires particularly reliable defect monitoring as a result of the high stress of the encasing film, which is to be ensured using the concept provided here. The encasing film may be designed as a bag, as already explained, in which during the manufacturing process of the electrochemical store, a cell winding having the electrolytes may be inserted and the opening of which may subsequently be welded or closed fluid-tight in another way. The anode and the cathode may penetrate the encasing film at such a closure seam, for example, and thus ensure the electrical connection of the cell winding. The state variable represented by the expansion state of the encasing film may be a value for a state of charge or a value for a state of aging or health of the electrochemical store.
In the electrochemical store, an electrical contact of the galvanic element may be electrically conductively connected to an electrical terminal of the force sensor. Furthermore, a further electrical contact of the galvanic element may be electrically conductively connected to a further electrical terminal of the force sensor. The force sensor may advantageously be supplied with an operating voltage or with electrical energy in general via the contact or contacts of the galvanic element. Additionally or alternatively, information may be transmitted via the contact or contacts of the galvanic element, or information or data may be transmitted to the force sensor or may be emitted from the force sensor.
The electrochemical store may also furthermore have at least one further sensor, in particular a temperature sensor, a pH value sensor, a half-cell voltage measurement sensor, or a further force sensor. The electrical contact of the galvanic element may be electrically conductively connected to an electrical terminal of the at least one further sensor. An integration of further sensors in the electrochemical store, for example, a pouch cell, is thus possible. The at least one sensor may be powered via the cell voltage. The signal communication of the at least one sensor may take place via a power line. According to this specific embodiment, manifold measured values may be made to be detectable, so that, for example, with the aid of redundancy values, measurement results may be verified in a simple way.
An electrochemical storage system for converting chemical energy into electrical energy has the following features:
a plurality of above-explained electrochemical stores, which are situated in the form of a stack; and
a frame unit for fixing a position of each of the plurality of electrochemical stores in the stack.
The electrochemical storage system may be used, for example, as a battery for driving an electric vehicle or hybrid vehicle. For this purpose, the plurality of electrochemical stores situated in a stack may be combined to form a battery pack with the aid of the frame unit. The battery pack may be designed in such a way that the individual electrochemical stores are packed closely against one another on the main sides of the particular encasing films and all contacts of the electrochemical stores protrude out of the frame unit pointing in the same direction, so that electrical voltage generated in the electrochemical storage system may be tapped there readily.
The present invention furthermore provides a flexible film for an encasing of a galvanic element, the flexible film having a force sensor. The flexible film may have the force sensor on a surface. Alternatively, the force sensor may also be welded into the flexible film. The flexible film having the force sensor may be manufactured in a separate manufacturing method, for example, and to finish an above-described encasing film, may be fastened, for example, glued at a suitable position thereon. Such a flexible film may provide additional protection for the force sensor and improve a fixed connection of the force sensor to the surface of the encasing film.
A method for determining a state variable of an electrochemical store for converting chemical energy into electrical energy, the electrochemical store having a galvanic element enclosed by an encasing film, includes the following steps:
detecting an expansion state of the encasing film; and
ascertaining the state variable, based on the expansion state.
Individual or all steps of the method may be carried out, for example, by a control unit, which may be connected via a CAN bus of a vehicle to the electrochemical store. A suitable algorithm may be used to ascertain the state variable, for example. The control unit may be designed to carry out or implement the steps of the method according to the present invention in corresponding units. The object on which the present invention is based may also be achieved rapidly and efficiently by this embodiment variant of the present invention in the form of a control unit.
A control unit may be understood in the present case as an electrical device, which processes sensor signals and outputs control and/or data signals as a function thereof. The control unit may have interfaces which may be implemented in hardware and/or software. In the case of a hardware implementation, the interfaces may be part of a so-called system ASIC, for example, which contains greatly varying functions of the control unit. However, it is also possible that the interfaces are separate integrated circuits or are made at least partially of discrete components. In the case of a software implementation, the interfaces may be software modules, which are provided on a microcontroller in addition to other software modules, for example.
According to one specific embodiment of the method, in the step of detection, a first expansion state in a middle area of a main side of the encasing film may be detected and/or a second expansion state in an edge area of a main side of the encasing film may be detected. Correspondingly, in the step of ascertainment, a first state variable based on the first expansion state may be ascertained and/or a second state variable based on the second expansion state may be ascertained, the first state variable being able to represent a state of charge of the electrochemical store and the second state variable being able to represent a state of aging of the electrochemical store. Using a simultaneous state detection at different relevant positions of the electrochemical store, misinterpretations with regard to a cause of an expansion of the encasing film may be avoided. Furthermore, after a successful association of detected measured values with the particular state, suitable measures may be taken. Thus, for example, in the case of a measured value which describes a state of charge of the electrochemical store, for example, presently prevailing pressure conditions may be inferred and, for example, more rapid charging or discharging of the electrochemical store may be initiated. A force sensor used for the detection of the state of charge may be situated in the middle on a main side of the encasing film, for example, where it may detect informative expansion measured values in conjunction with the “respiration” of all cells in a battery pack. On the other hand, it may be established using a measured value which describes a state of aging or state of health of the electrochemical store, because the associated force sensor is situated in an edge area uninfluenced by the cell respiration, that the electrochemical store should be replaced during the next maintenance as a result of degassing processes.
A computer program product having program code, which may be stored on a machine-readable carrier such as a semiconductor memory, a hard drive memory, or an optical memory and may be used to carry out the method according to one of the above-described specific embodiments when the program product is executed on a computer or in a device, is also advantageous.
The present invention will be explained in greater detail hereafter as an example on the basis of the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A-1C show views of different embodiments of pouch cells.
FIG. 2 shows a perspective view of an electrochemical storage system.
FIG. 3 shows a perspective view of a frame element of the electrochemical storage system from FIG. 2 .
FIG. 4A shows a schematic view of an electrochemical store having an encasing film according to one exemplary embodiment of the present invention.
FIG. 4B shows a schematic view of a section of the electrochemical store from FIG. 4A .
FIG. 5 shows a schematic view of a section of an electrochemical store having an encasing film according to another exemplary embodiment of the present invention.
FIG. 6 shows a schematic view of a section of an electrochemical store having an encasing film according to another exemplary embodiment of the present invention.
FIG. 7 shows a schematic view of a section of an electrochemical store having an encasing film according to another exemplary embodiment of the present invention.
FIGS. 8A-8C show schematic views of different contacting possibilities of a force sensor of an electrochemical store having an encasing film, according to exemplary embodiments of the present invention.
FIG. 9 shows a flow chart of a method for determining a state variable of an electrochemical store, according to one exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
In the following description of preferred exemplary embodiments of the present invention, identical or similar reference numerals are used for the elements which are shown in the various figures and act similarly, a repeated description of these elements being omitted.
FIGS. 1A through 1C show illustrations of commercially-available pouch cells 100 in different specific embodiments.
It is apparent from the illustrations that cells 100 are embodied as a so-called soft pack, i.e., do not have a rigid housing, but rather a flexible jacket or encasing film. FIG. 1C shows a soft pack 100 inflated from gas development. Such gas development typically occurs when aging of cell 100 has reached a critical point, and cell 100 should be deactivated before the internal gas pressure may cause bursting of the soft pack and escape of hazardous cell components.
FIG. 2 shows a perspective view of an electrochemical storage system 200 . Electrochemical storage system 200 includes a plurality of electrochemical stores in the form of pouch cells 100 , as are shown as examples in FIGS. 1A through 1C . Electrochemical stores or pouch cells 100 are situated in the form of a recumbent stack and are fixed in their particular position by a frame unit 210 . Pouch cells 100 are enclosed by frame unit 210 in such a way that only contacts 220 for the electrical connection of electrochemical storage system 200 protrude beyond an upper edge of frame unit 210 . In a base area, frame unit 210 has a discharge channel 230 for dissipating heat from electrochemical storage system 200 .
FIG. 3 shows, on the basis of another perspective view, a frame element 300 of the frame unit shown in FIG. 2 of the electrochemical storage system. Frame element 300 is designed to enclose a pouch cell like a sandwich together with another such frame element, a clearance of frame element 300 being sufficiently large so it does not obstruct so-called respiration of the cell caused by charging and discharging of the pouch cell. The exemplary embodiment of frame element 300 shown here is conceived as an intermediate element of the frame unit shown in FIG. 2 and includes, in addition to the opening for above-explained discharge channel 230 , furthermore a screw feedthrough 310 for a connection of frame element 300 to a further frame element or a terminus plate for the frame unit, a passage opening for a cooling channel 320 for conducting a cooling fluid through the electrochemical storage system, an elastomeric seal 330 for the suitable sealing of the battery pack, and a recess 340 as a free space for an expansion of a pouch cell enclosed by frame element 300 . The view of frame element 300 in FIG. 3 shows that in electrochemical storage systems conceived in this way, the individual pouch cells touch on their main surfaces and alternating pressures corresponding to a particular state of charge of individual cells exist in the entire cell stack and these pressures pass through in a force path oriented transversely to frame element 300 .
FIG. 4A shows a schematic view of an electrochemical store 100 according to one exemplary embodiment of the present invention. Electrochemical store 100 is embodied as a pouch cell and may be used for the electrochemical storage system shown in FIG. 2 , for example. Electrochemical store 100 includes an encasing film 400 , a galvanic element 410 , a first film sensor or force sensor 420 , a second film sensor or force sensor 430 , and a first electrode 440 and a second electrode 445 for the electrical connection of galvanic element 410 . In the exemplary embodiment of electrochemical store 100 shown in FIG. 4A , electrode 440 , which is shown on top in the illustration, forms the cathode, and electrode 445 , which is shown on the bottom in the illustration, forms the anode. As already explained, encasing film 400 encloses galvanic element 410 , but is only shown as a frame enclosing galvanic element 410 for reasons of visibility here. The area of encasing film 400 visible in the figure identifies end sections of edge areas of the encasing film at the same time here. Galvanic element 410 has a cell winding for generating electrical energy from chemical energy. Furthermore, an auxiliary contact 450 for the voltage supply of second force sensor 430 is shown. For this purpose, second force sensor 430 is connected via a first terminal 460 to auxiliary contact 450 and is connected via a second terminal 470 to anode 445 . The voltage supply of first force sensor 420 is not shown in the illustration in FIG. 4A . For example, it may be situated on an inner side of encasing film 400 , which is not visible to the eye.
It is apparent from FIG. 4A that first force sensor 420 is situated in a middle area of encasing film 400 , as explained at the outset, the term “middle area” meaning the middle area in a top view of the encasing film. In this case, the top view is the view of the area of the encasing film having the largest extension. First force sensor 420 therefore lies in the force path, which was explained in conjunction with FIG. 3 , of a plurality of pouch cells 100 stacked one on top of another. First force sensor 420 measures in this case a force which results due to a volume change of cell layers (not shown in the illustration of FIG. 4A ), i.e., a stack made of a plurality of pouch cells 100 . The force may be detected, for example, in a capacitive, piezoresistive, or resistive way, for the resistive detection, for example, using a touchscreen, which reacts to a pressure which connects two electrically conductive layers at a point, or with the aid of a voltage divider. A measured value thus obtained enables, with suitable analysis, a determination of the SOC of electrochemical store 100 . Second force sensor 430 lies outside the force path in an edge area of encasing film 400 and therefore at a point at which encasing 400 of cell 100 may expand unobstructed by other cells 100 of a stack. At this point, an influence of an internal gas pressure of pouch cell 100 may be detected, specifically via an expansion which it induces in encasing film 400 . Thus, using suitable analysis of a detected measured value, a determination of the state of health of electrochemical store 100 may be carried out here. In the exemplary embodiment shown here, second force sensor 430 is printed onto encasing film 400 . Alternatively, a MEMS element may also be applied for the force detection, specifically on the inner side or outer side of encasing film 400 . In first force sensor 420 and second force sensor 430 , the detection takes place in each case based on an expansion of a strain gauge used in the sensors.
In principle, both film sensors 420 , 430 may be applied to the inner side or outer side of encasing film 400 . Temperature sensing may take place separately via a film sensor, for example, locally or via an array. The sensing may be carried out resistively, for example, via a resistor which only changes via the temperature. According to specific embodiments of electrochemical store 100 which are not shown in the figures, terminals 460 , 470 of first force sensor 420 or of second force sensor 430 or both force sensors 420 , 430 may be led outward in the case of internal arrangement of sensors 420 , 430 . Alternatively, terminals 460 , 470 may also be placed exclusively inside encasing film 400 of pouch cell 100 and may also be connected to a main power line of electrochemical store 100 inside pouch cell 100 . Of course, terminals 460 , 470 of film sensors 420 , 430 which use them may also be led on or also inside pouch cell 100 .
FIG. 4B shows a section of an electrochemical store 100 from FIG. 4A on the basis of another schematic view. The detailed view shows a front area, which is on the right in the view in FIG. 4A , of pouch cell 100 to illustrate the contacting variants selected in this exemplary embodiment of the film sensors on the example of second force sensor 230 . The view in FIG. 4B is a cross section on external encasing 400 of pouch cell 100 and shows an interior of pouch cell 100 , like FIG. 4A . As already explained, force sensor 430 is connected via a first terminal 460 to auxiliary contact 450 and is connected via a second terminal 470 to anode 445 . As the view in FIG. 4B shows, cathode 440 , anode 445 , and auxiliary contact 450 break through the edge area of encasing film 400 on one side. A seal seam or a seal frame ensures a fluid-tight closure of encasing film 400 and compresses metal contacts 440 , 445 , 450 and, for example, a conductive coating of an inner side of encasing 400 . In this way, an electrical contact of cell 100 and sensor 430 may be achieved with a fluid-tight seal. In the event of a crack or another failure of the weld seam in the area of the film welded connection, for example, because of strong degassing in electrical element 410 , one or all of electrical contacts 440 , 445 , 450 will disconnect. A signal thus triggered may indicate, for example, to a battery management system, a cell defect. Alternatively, this functionality may also be provided at any arbitrary other point of electrochemical store 100 . Contacts 440 , 445 , 450 are printed here on the internal surface of encasing film 400 . Contacts 440 , 445 , 450 extend beyond an edge of encasing film 400 .
FIG. 5 shows a further contacting possibility of second sensor 430 on the basis of another schematic view of the section of electrochemical store 100 from FIG. 4B . In addition to auxiliary contact 450 , a further auxiliary contact 500 is used here. In contrast to the exemplary embodiment of pouch cell 100 shown in FIG. 4B , second terminal 470 does not connect sensor 430 to anode 445 , but rather to further auxiliary contact 500 .
FIGS. 6 and 7 show detailed views to illustrate possible contacting variants of the film sensors on the basis of the example of force sensor 430 , which is designed here as an integrated gas pressure sensor. The views again show a cross section on external encasing 400 of pouch cell 100 . In both figures, force sensor or gas pressure sensor 430 is embodied having a separate introduced carrier film 600 . Film 600 is flexible and therefore does not obstruct expansion of a strain gauge used in force sensor 460 . As is apparent from the views in FIGS. 6 and 7 , flexible carrier film 600 completely covers or encloses sensor 430 . Alternatively, a MEMS sensor element (MEMS=micro-electromechanical system) may be applied to carrier film 600 for the expansion detection.
FIG. 6 shows an exemplary embodiment of electrochemical store 100 having film-applied gas pressure sensor 230 , in which first terminal 460 and second terminal 470 each form independent contacts for the voltage supply of gas pressure sensor 430 .
The exemplary embodiment shown in FIG. 7 differs from that shown in FIG. 6 in that first terminal 460 connects gas pressure sensor 230 to cathode 440 here.
FIGS. 8A through 8C show schematic views of various contacting possibilities of a force sensor of an electrochemical store having an encasing film. In each case, the section of electrochemical store 100 already shown in FIGS. 4B through 7 is shown in a cross-sectional view, tilted by 90°. As an example, a contacting of force sensor 430 with cathode 440 is examined here. Force sensor 430 is always situated on an outer side of encasing 400 in the exemplary embodiments shown in FIGS. 8A through 8C .
FIG. 8A shows a starting situation before electrical contacting of force sensor 430 . The challenge in this case is establishing a reliable electrical contact between an electrical terminal of force sensor 430 and electrode 440 .
FIG. 8B shows an establishment of the contact via a conductive adhesive connection 800 . Conductive adhesive connection 800 establishes an electrically conductive connection between an electrical terminal of force sensor 430 and electrode 440 .
FIG. 8C shows an establishment of the contact via a type of stamped contact or through contact 810 . A glued-on auxiliary film 820 is used for the bridging here. If the contacting is established in the area of a weld seam of encasing film 400 , auxiliary film 820 may also be omitted. Alternatively, thick-film pastes, bond wires, and bond strips may also be used instead of auxiliary film 820 .
FIG. 9 shows an exemplary embodiment of a flow chart of a method 900 for determining at least one state variable of an electrochemical store. The method is used in an electrochemical store, which was explained on the basis of the preceding figures, which has a galvanic element enclosed by an encasing film. In a first step 910 , an expansion state of the encasing film is detected. The expansion state of the encasing film may be detected at different positions of the encasing film, for example, in a middle area and in an edge area—simultaneously or offset in time—to be able to detect different state variables of the electrochemical store. Based on the expansion state, in a following step 920 , at least one state variable of the electrochemical store may be ascertained. Using a state variable, which was ascertained based on the measurement in the middle area of the encasing film, a state of charge of the electrochemical store may accordingly be inferred, while a state variable, which was ascertained based on the measurement in the edge area of the encasing film, would give indications of a state of aging or state of health of the electrochemical store.
Method 900 is designed in such a way that the fact is taken into consideration that the pressures and forces mutually influence one another inside a pouch cell stack. Method 900 also delivers informative measured values when the film sensors used are powered via the cell voltage. Method 900 may include the signal communication preferably taking place via the power line, both contacts of the sensors or integrated analysis electronics then being connected to the cell poles. According to other exemplary embodiments, method 900 is conceived in such a way that the state monitoring (exceeding of critical reference values) relays a warning signal to the battery management system via an analysis unit (ASIC), or a periodic equalization of the internal pressure sensor or gas pressure sensor with the external pressure takes place. Method 900 may also include a detected loss of the hermetic seal or a critical state of health being communicated to the central vehicle control unit and/or the driver, for example, via a warning light, or decoupling or bypassing of the damaged cell taking place in the event of a critical detected loss of the hermetic seal or a critical state of health. Furthermore, one embodiment shows the use of measured values of a (low-pressure) external pressure sensor for comparison to the measured values of the pouch cell sensor or internal gas pressure sensors by the equalization function. In another exemplary embodiment, the equalization is performed as a follow-up, for example, during the base state of the battery. In another embodiment, a characteristic diagram is used to calculate the measured values, which contains at least one empiric data value obtained from measurement trips, for example, so that an exemplar-specific equalization of the system pouch cell—film sensor may be carried out. Alternatively, the gas pressure sensor may be omitted and the state of health or gas pressure may be calculated via averaging over charging or discharging cycles.
Method 900 may be used independently of whether sensor films are situated in or on pouch cells, and enables a use of the film sensor for monitoring mechanical tensions, before a crack of the external encasing occurs as a result of resulting stresses. Correspondingly, a minimization of the safety risk may be achieved. More rapid charging and discharging of the battery cells, which may be monitored, may also be implemented because of the detection of the pressure conditions.
The exemplary embodiments which are described and shown in the figures are only selected as examples. Different exemplary embodiments may be combined with one another in their entirety or with regard to individual features. One exemplary embodiment may also be supplemented by features of another exemplary embodiment. Furthermore, method steps according to the present invention may be carried out repeatedly and in a sequence other than that described. | An encasing film for a galvanic element has at least one force sensor for detecting an expansion state of the encasing film. The encasing film is produced from an elastic and electrically insulating material, e.g., plastic. The force sensor, which has a strain gauge, is situated on a surface of the encasing film. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a Continuation-in-Part of co-pending U.S. patent application Ser. No. 09/590,992 filed on Jun. 9, 2000.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to hand held video games, and more particularly, to a releasably attachable light assembly for the hand held video game which enables game playing in low light conditions.
2. Description of the Related Art
Compact computers and video game devices having video viewing screens are becoming more and more popular and typically comprise hand-held portable, battery-operated devices. The viewing screen is typically a liquid crystal display (LCD) that is generally flat and displays information and or provides the screen for playing video games. Such compact computers and video games may include, but are not limited to: calculators, computer video games, lap top computers, and other computers where a variety of software is employed. In particular, compact video games, such as the compact video game systems known as GAME BOY™, GAME BOY POCKET™ and GAME BOY COLORS™ (Trademarks of Nintendo of America), are completely self-sustained video game systems which may be operated by interchangeably employing a collection from a library of software game packs. These Nintendo video game systems provide a compact, self-contained, battery-operated, portable hand-held computer with a cross key joy stick (directional-pad or D-pad) to operate the game, start and select buttons, action buttons and an LCD-type screen, together with volume controls so as to display and enable the user to display images and play games.
While video display screens are employed and typically include a flat LCD-type screen, such LCD-type display screens are often difficult to observe by the user in partial or low light conditions, such as, for example, automobiles, planes, trains, buses, and the like due to the lack of illumination on the LCD screen to permit suitable contrast during use.
U.S. Pat. Nos. 5,091,832 and 5,325,280 show a light apparatus for use with compact computer screens. As shown and described, the body includes an open video space designed to be the same size as the LCD video screen of the compact computer apparatus. The body includes a pair of sloped or angled white colored side panels and a top and bottom side panel and the white or light colored extending directly generally perpendicular to the video screen rather than sloped as illustrated for the side panels. The top side panel is integral with and extends from the bottom molded section of the body when the body sections are matingly engaged to form the body, the top panel with the panels on the top section then form a rectangular, open video viewing space of the apparatus.
The light apparatus includes a pair of light bulbs placed on either side of sloping panels and which side panels also include a short, solid, upward extending light shield so as to prevent the direct glare of the light bulbs onto the LCD screen and to provide for indirect lighting through reflection on the light-colored side panels onto the LCD viewing screen.
U.S. Pat. Nos. 5,117,339 and 5,165,779 disclose combined light and magnifier devices for hand-held computers with video screens. Each of these patents show a battery operated light assembly that is mounted to a separate assembly mounted adjacent the view screen and spaced from the magnifier lens. The devices shown in these patents are adapted to provide a screen magnifier while also providing additional light to the screen for playing in low light conditions.
Unfortunately, the use of an LCD screen in these hand-held video game devices makes the illumination of the same difficult. The primary reason for this difficulty is due to the fact that the plastic cover to the actual LCD screen is generally of a high-gloss finish, and as such has a tendency to reflect light. This reflection of light primarily occurs when the light shines substantially directly onto the screen, and thus, the high-gloss screen cover prevents the light from penetrating the cover and thereby illuminating the LCD screen.
In all of the aforementioned patents, the lighting assemblies utilize various different light sources that are generally directed toward the screen. The use of white or light colored frame sides is implemented in an effort to diffuse the light before projected onto the screen, however, neither the white or light colored sides of the fame prevent spotting or “hot spots” caused by the illumination of the light source immediately adjacent the viewing screen or even worse, when positioned so as to project light directly at the viewing screen. As such, the light source, in the area of disposition, causes a glare spot or “hot spot” on the high-gloss glass cover to the actual LCD display screen. Thus, the user's view is obstructed and not increased in these hot spot areas. Furthermore, dark spots are created on the screen where the additional light is not effectively distributed across the screen. In view of these drawbacks of the prior art patents, it would be desirable to provide a lighting assembly for a hand-held computer gaming device that does not have any screen “hot spots” or dark spots, and actually works to increase the viewing of the display screen.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide an improved lighting assembly for hand-held video games that does not cause “hot spot” or other glaring effects from the use of light source to illuminate the LCD display.
It is yet another object of the invention to provide an improved lighting assembly for hand-held video games that effectively utilizes reflection techniques to efficiently illuminate the LCD display screen of the game device.
This and other objects are achieved in accordance with an embodiment of the present invention in which a light assembly for use in enhancing the view of a compact computer video screen includes a base portion adapted to fit over a top edge of the compact computer device. An upward extension is pivotally connected to the base portion and a reflector housing is pivotally connected to the upward extension. A light source is disposed within a recess in the upward extension and positioned so as to direct light away from the video screen. A reflector is disposed on the underside of the reflector housing and is adapted to reflect light from the light source downward toward the video screen. Through the variable positioning of the upward extension and reflector housing (via the pivotal connections) the user can selectively adjust the amount of light reflected down onto the video display screen.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings wherein like reference numerals denote similar elements throughout the several views:
FIG. 1 a is a perspective view of the game light assembly according to an embodiment of the invention;
FIG. 1 b is a perspective view of the game light assembly with the game playing apparatus shown in phantom;
FIG. 1 c is a perspective view of the game light assembly according to another embodiment of the invention;
FIG. 1 d is a bottom view of the game light assembly according to the embodiment of FIG. 1 c;
FIG. 1 e is a bottom view of the game light assembly according to another embodiment of the invention;
FIG. 1 f is a top view of the game light assembly according to the embodiment of FIG. 1 e;
FIG. 2 is a front view of game light assembly according to an embodiment of the invention;
FIG. 3 a is a side view of the game light assembly according to an embodiment of the invention;
FIG. 3 b is a side view of the game light assembly according to an embodiment of the invention;
FIG. 3 c is a perspective view of the base portion of the game light assembly according to another embodiment of the invention;
FIG. 4 is a rear view of the game light assembly according to an embodiment of the invention;
FIG. 5 is a bottom view of the game light assembly according to an embodiment of the invention;
FIG. 6 is a perspective view of the game light assembly in an extended flattened position;
FIG. 7 is a perspective view of game accessory power supply connector for compact video game devices according to an embodiment of the present invention;
FIG. 8 is a side view of the game accessory power supply connector according to the invention;
FIG. 9 is a bottom view of the game accessory power supply connector according to the invention;
FIG. 10 a is top perspective view of the game accessory power supply connector for compact video game devices according to another embodiment of the invention;
FIG. 10 b is a bottom perspective view of the game accessory power supply connector for compact video game devices according to another embodiment of the invention;
FIG. 11 is a top view of the game accessory power supply connector depicted in FIG. 10 a as disposed on a compact video game device shown in phantom; and
FIG. 12 is a cross-sectional view of the game accessory power supply connector taken along lines XII—XII of FIG. 11 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1 a and 1 b show the light assembly 10 according to an embodiment of the invention. Light assembly 10 includes a base portion or housing 12 adapted to be releasably attached to a hand held video game device 5 and an upper portion having an upward extension 14 and reflector housing 16 . According to one embodiment, the base portion 12 has a left side 24 that includes a power supply plug 28 which is adapted and positioned to be inserted into an external port of the hand held video game device. Power supply plug 28 engages the external port of the hand held video game device 5 when disposed in its operable position (shown in FIG. 1 b ) and thereby electrically connects the light assembly 10 to the battery power supply of the game device 5 . The external port of the game device may be an external link port for linking the game device 5 to another game device and enabling head to head competition and multi-player game action. In addition, the external port may be any other port capable of carrying low voltage DC power, for example, a universal serial bus (USB) port (type A and/or B), a FIREWIRE™ port, a networking port (RJ-45), a telephone jack (RJ-11), an AC adapter port capable of providing access to the game device power supply, an earphone or head phone jack, etc. In this manner, the light assembly 10 does not need its own power supply or batteries. In one embodiment, an on/off power switch 50 can be provided on the base portion 12 which allows the user to selectively turn on and off the light assembly 10 . In another embodiment, there is no power switch on base portion 12 and the light assembly is powered on and off with the switching on and off of the game device. Those of ordinary skill in the art understand that the electrical connections made within the light assembly and the manner of manufacturing the same may be made by any suitable known type of electrical connections and manufacturing methods. Light assembly 10 is preferably made of molded plastic to dimensionally fit the Game Boy™, but may also be made of any suitable known material capable of being shaped into a desired style.
FIGS. 1 c - 1 e and FIG. 4 show various other embodiments where the light assembly 10 includes its own power source. Referring to FIGS. 1 c and 1 d , a battery compartment 25 is provided within base portion 12 and includes an access cover 27 that is releaseably connected to base portion 12 with a snap or other suitable connection. The size and type of battery or batteries 29 contained within the compartment 25 is a matter of design choice. Those of ordinary skill in the art will recognize that the type of battery and size thereof can be modified without departing from the spirit of the present invention. FIGS. 1 e and If show the disposition of the battery compartment 25 within reflector housing 16 . In this embodiment, the reflector 18 is connected to or integrally formed with the compartment cover 31 . Thus, the battery(ies) 29 are covered by the compartment cover 31 and are thereby contained within housing 16 underneath the reflector 18 . FIG. 4 shows another embodiment where the battery compartment 25 is disposed within upward extension 14 and covered by a compartment cover 33 . Compartment cover 33 is preferably molded to conform to the shape and texture of the upward extension 14 and thereby is concealed from obvious view. Those of ordinary sill in the art will appreciate that the actual location of the battery compartment 25 within the light assembly 10 is also a matter of design choice.
Light assembly 10 is disclosed in the style of a cobra snake. Those of skill in the art will recognize that the concepts and technology disclosed herein may be applied to a light assembly of any style and shape. Thus, the cobra style depicted herein is only one exemplary embodiment style of the light assembly of the present invention. In addition, the lighting system and technology of the present invention can be used for other applications such as, for example, a book light.
The upward extension 14 includes a recess 22 adapted to receive and house a light source 20 that is directed upward away from the display screen 7 of the game device 5 . Light source 20 can be any suitable known light source such as, for example, an incandescent bulb, a light emitting diode (LED), a directional LED, etc. A directional LED provides substantially collimated beam of light that is easily directable toward a particular surface. Those of skill in the art will recognize that the type of light source may be a matter of design choice and may be changed without departing from the spirit of this disclosure. In one preferred embodiment, the light source includes a lens or other means for facilitating the directability or focusing of the light toward the reflective surface. In another preferred embodiment, recess 22 is formed by providing an additional cavity 23 (FIG. 3 b ) that protrudes from the backside of the upward extension 14 . This cavity 23 forms the recess 22 on the front side of the upward extension 14 .
The base portion or housing 12 of the light assembly 10 includes various integrated extensions 34 , 36 and 38 in order to increase its strength and integrity during attachment and detachment to and from the game device 5 . Those of ordinary skill in the art will recognize that other methods and designs for these portions of base 12 can be altered without departing from the scope of the invention. FIGS. 10 a - 12 show another embodiment of the base portion or housing (to be discussed later) that eliminates extensions 34 , 36 and 38 and provides a stronger design by integrating thicker support ribs and facia or upper rim 102 . The left side 24 of the base portion or housing 12 includes a power supply plug 28 that is positioned so that when light assembly 10 slidably engages the game device 5 in the direction shown by the arrow in FIG. 1 a , power supply plug 28 is inserted into the external port (not shown) of the game device 5 . Although the preferred external port of the game device 5 is generally used to link the game device to another for head-to-head game playing, by designing plug 28 to contact select electrical contacts within the link port, light assembly 10 can utilize the power of the game device (e.g., internal or external battery power supplies) to power light source 20 . The external port may also be other communication or power ports provided on the game device from which DC power to illuminate the light assembly can be obtained. Thus, the use of other additional power supplies or batteries to power the light assembly are not necessary. In one embodiment (discussed later with respect to FIGS. 3 a - 3 c ), access to the external port will continue to be provided while the light assembly 10 is mounted in its operable position on game device 5 . The game device 5 also includes a volume control (not shown) that is disposed adjacent the link port. As such, the left side 24 of the base portion 12 is designed so as to not interfere with the operation of the adjacently positioned volume control dial.
Depending on the particular game device 5 , an infrared (LR) window (not shown—e.g., GAME BOY™ and GAME BOY COLOR™) or on/off power switch (not shown—e.g., GAME BOY POCKET™) is disposed on the top edge of the game device. As such, base portion/housing 12 includes a cutout or opening 30 (FIGS. 1 a , 1 b and 2 ) positioned so as to accommodate the IR window or on/off switch on the game device and keep them accessible when light assembly 10 is disposed in its operable position.
Referring to FIGS. 1 a , 1 b , 3 a , 3 b and 5 , during operation light source 20 is illuminated and positioned within recess 22 such that the light emanating therefrom is directed upward toward reflector housing 16 and away from display screen 7 . As shown in FIG. 5, reflector housing 16 includes a substantially flat reflector 18 disposed on the underside of the housing. Through the use of hinges 40 and 42 , the reflector housing 16 and upward extension 14 can be selectively positioned to reflect the light back down toward the display screen 7 of the game device 5 . Reflector 18 can be any suitable known type of reflector such as, for example, a mirror, reflective mylar, hot stamped chrome plate etc. It is also contemplated to have reflector 18 integrally formed into the underside of the reflector housing 16 . As mentioned previously, light source 20 is directed upward toward reflector 18 on the underside of housing 16 . As such, the light emanating from light source 20 is reflected downward by the reflector 18 and thereby illuminates the display screen 7 in an even and diffused manner. As shown in FIGS. 3 a and 3 b , through the application of hinged connections 40 and 42 , the user can manipulate the angular positions of upward extension 14 and reflector housing 16 to adjust the angular position of reflector 18 with respect to the light source, and thereby enables the user to increase and/or decrease the amount of light being directed toward display screen 7 corresponding to the angular position of the reflector. In other embodiments (not shown), hinges 40 and 42 can be eliminated and light assembly 10 with base portion 12 , upward extension 14 and reflector housing 16 are predeterminately positioned and molded so as to provide the maximum lighting ability for the display screen 7 of the game device 5 .
In view of the fact that light assembly 10 can utilize an external port of the game device 5 in order to obtain power (e.g., the link port), an additional port 44 (FIGS. 3 a and 3 b ) is provided on the external surface of the base portion 12 so as to provide the user with all the functionality of such port while the light assembly 10 is disposed in its operable position on the game device 5 . For example, when using the link port of the game device 5 , the additional port 44 provides the user with the continued ability to link to another game device using an appropriate link wire. FIG. 3 c shows another embodiment of the positioning of additional port 44 on the external surface of base portion 12 . Those of ordinary skill in the art will recognize that the position of the externally provided port 44 can be changed without departing from the spirit of this disclosure.
FIG. 5 shows a bottom view of the light assembly 10 and how the base portion 12 engages the game device 5 according to one preferred embodiment. The right side 26 of base portion 12 includes a small flange 52 adapted to engage the corresponding top corner of the game device 5 . When base portion 12 is slid onto the top edge of the game device (see arrow direction in FIG. 1 a ) flange 52 snaps over the top corner edge of the game device. This “snap over” flange 52 , in conjunction with the power supply connection 28 with the external port of the game device 5 , secures the light assembly 10 into its operable position on the game device. Conversely, the removal of light assembly 10 simply requires the user to “un-snap” flange 52 from its secured position over the top edge and slide the base portion 12 of the light assembly in the reverse direction of the arrow indicated in FIG. 1a for removal from the game device 5 .
FIG. 6 shows the light assembly 10 in a flattened position over the game device 5 . Through the hinged connection 40 of the reflector housing 16 with upward extension 14 and the hinged connection 42 of the upward extension with the base portion 12 , the light assembly 10 can be flattened over the game device 5 and screen 7 as shown. This folding aspect (or un-folding) of the light assembly not only functions to place the light assembly 10 into a storage position without requiring its removal from the game device, but also functions to protect the upper surface of the game device 5 .
FIGS. 7-9 shows a game accessory power supply connector 70 for use with any type of accessory item. The game accessory power supply connector 70 can be integrated into any type of accessory item for the game device. It is preferable that the particular type of accessory item be one that requires battery power to operate, thus enabling the use of the game device link port as described in several embodiment of the invention. Game accessory power supply connector 70 includes a base portion 71 that is substantially identical to the base portion 12 of the light assembly 10 . Briefly, the base portion 71 includes left and right sides 80 and 82 , respectively, the IR window—on/off switch opening 76 , an on/off switch 74 and the power supply plug 72 . Base portion 71 also includes an external port 86 which can be variously positioned on connector 70 according to design choice.
The connection of the game accessory power supply connector 70 is also identical to that of the base portion 12 of the light assembly 10 . Thus, when the connector 70 is slid onto the top edge of the game device (see arrow direction in FIG. 1 a ) flange 84 snaps over the top corner edge of the game device. This “snap over” flange 84 secures the connector 70 into its operable position on the game device. The removal of connector 70 is also identical to that of base portion 12 described earlier.
FIGS. 10 a and 10 b show a preferred embodiment for a game accessory power supply connector 100 according to the invention. Connector 100 has an upper surface 102 on which hinge 106 is disposed for connection to, for example, the upward extension 14 (FIGS. 1 a and 1 b ). The rear side 101 of connector 100 includes the IR/on/off switch window 110 and the external link port 114 is provided on one side. Similar to the flange 52 described with reference to the embodiment of FIG. 5, connector 100 includes flange 104 adapted to snap over the top corner edge of the game device 5 . The upper surface 102 of connector 100 is designed to be thicker than that of the previously discussed embodiments, and as such the structural integrity of the connector is substantially increased. Those of ordinary skill will appreciate that other designs for increasing the overall integrity and strength of the connector can be made without departing from the spirit of the present invention.
Connector 100 engages the game device 5 is a slightly more enhanced manner than that of the aforementioned embodiments. Referring to FIGS. 11 and 12, the game device 5 includes a display screen 7 that is covered by a glass or plastic panel 9 that is larger than the display screen. Panel 9 meets with the upper edge 11 of the game device 5 and is slightly recessed from this upper edge 11 so as to form a small ledge between the panel 9 and edge 11 . Connector 100 includes a flange 112 extending downward from the upper surface 102 and positioned such that the upper surface 102 substantially extends across the upper edge 11 of the game device 5 and flange 112 engages over the small ledge formed with panel 9 and thereby secures connector 100 to the top edge of the game device 5 . An optional on/off switch 116 is also provided.
While there have been shown and described and pointed out fundamental novel features of the invention as applied to preferred embodiments thereof, it will be understood that various omissions, substitutions, changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto. | A lighting assembly for compact computer devices such as, or example, hand held video games utilizes a light source directed away from the display screen of the compact computer device and a reflective surface selectively positionable over the display screen to intercept and reflect the light emanating from the light source and re-direct it toward the display screen. The directing of the light away from the display screen and subsequent reflecting back toward the display screen results in an evenly diffused light being applied to the display screen, while completely eliminating the otherwise experienced hot spots or dark spots common in prior art light assemblies. | 5 |
BACKGROUND OF THE INVENTION
1. of the Invention
The present invention relates to a semiconductor device, and more particularly, to a thin film transistor and method for fabricating the same for facilitating charge transport between source and drain and reducing an operating gate voltage.
2. Discussion of the Related Art
A thin film transistor formed with an amorphous silicon layer has been widely used as a switching device of a liquid crystal display and a linear image sensor. A thin film transistor is a field effect transistor that has a metal-insulator-semiconductor (MIS) structure. Thus, it is preferable to form the thin film transistor in self-alignment similar to a conventional MOS transistor. This is because, in this way, it is possible to reduce the parasitic capacitance and simplify photolithography.
A conventional method for fabricating a thin film transistor will be explained below with reference to FIGS. 1a and 1b. As shown in FIG. 1a, a conductive layer is deposited on a transparent insulating substrate 1, and patterned to form a gate electrode 2. Then, a gate insulating layer 3 is deposited on the overall surface of the substrate. An amorphous silicon layer 4 is formed on the gate insulating layer 3. An impurity-doped semiconductor layer 5 is deposited on the amorphous silicon layer 4.
As shown in FIG. 1b, a metal is deposited on the impurity-doped semiconductor layer 5, and patterned to form source and drain electrodes 6. A predetermined portion of the impurity-doped semiconductor layer 5 is selectively etched using the source and drain electrodes 6 as a mask. Then, a passivation layer 7 is deposited and selectively etched to form a contact hole which exposes a portion of the source or the drain electrode 6. A transparent conductive layer is deposited on the overall surface of the substrate and patterned to form a pixel electrode 8. The pixel electrode 8 is connected to the source or the drain electrode 6 through the contact hole, and thus, completing the thin film transistor.
In the above mentioned conventional method, an ohmic contact layer can be made of silicide. In this case, instead of depositing an impurity doped semiconductor layer, reaction of the amorphous silicon layer 4 with the metal forming the source and drain electrodes 6 can be utilized to form the ohmic contact layer.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a method for fabricating a thin film transistor that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a method for fabricating a thin film transistor having a short carrier traveling path using a simpler process than in the conventional method.
Another object of the present invention is to provide a method for fabricating a thin film transistor for facilitating charge transport between the source and drain and reducing an operating gate voltage.
Additional features and 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 objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, the method for fabricating a thin film transistor includes the steps of forming a gate electrode on a transparent insulating substrate; forming a gate insulating layer on the overall surface of the substrate; forming a metal layer on the gate insulating layer; patterning the metal layer to form source and drain electrodes; forming a silicon layer on the substrate on which the source and drain electrodes are formed; patterning the silicon layer into an active layer pattern; carrying out heat treatment; and forming a pixel electrode to be connected to the source and drain electrodes.
In another aspect, the present invention provides a method for fabricating a thin film transistor having a substrate comprising the steps of forming a gate electrode on the substrate; forming a gate insulating layer on the gate electrode and the substrate; forming source and drain electrodes having side surfaces facing each other on the gate insulating layer; forming an active layer over the source and drain electrodes and the gate insulating layer; and forming a silicide layer on at least one of the side surfaces of the source and drain electrodes.
In another aspect, the present invention provides a method for fabricating a transistor having a substrate comprising the steps of forming a gate electrode on the substrate; forming an insulating layer over the gate electrode and the substrate; forming source and drain electrodes having side surfaces facing each other over the gate insulating layer; forming an active layer over the source and drain electrodes and the insulating layer above the gate electrode; forming a silicide layer on at least one of the side surfaces of the source and drain electrodes; forming a pixel electrode in contact with one of the source and drain electrodes; and forming a passivation layer over the active layer, the source and drain electrodes, and the pixel electrodes.
In another aspect, the present invention provides a method for fabricating a transistor having a substrate comprising the steps of forming a gate electrode on the substrate; forming an insulating layer over the gate electrode and the substrate; forming source and drain electrodes having side surfaces facing each other over the gate insulating layer; forming an active layer over the source and drain electrodes and the insulating layer above the gate electrode; forming a silicide layer on at least one of the side surfaces of the source and drain electrodes; forming a passivation layer over the active layer, the source and drain electrodes, and the insulating layer, the passivation layer having a contact hole exposing a portion of one of the source and drain electrodes; and forming a pixel electrode in contact with one of the source and drain electrodes through the contact hole.
In another aspect, the present invention provides a thin film transistor comprising a substrate; a gate electrode on the substrate; an insulating layer on the gate electrode; source and drain electrodes having side surfaces facing each other over the insulating layer; an active layer over the source and drain electrodes and the insulating layer; and a silicide layer on at least one of the side surfaces of the source and drain electrodes.
In another aspect, the present provides a thin film transistor comprising a substrate; source and drain electrodes having side surfaces facing each other over the substrate; an active layer over the source and drain electrodes and the substrate; a silicide layer on at least one of the side surfaces of the source and drain electrodes; a gate insulating layer on the active layer; and a gate electrode over the gate insulating layer.
In a further aspect, the present invention provides a method for fabricating a thin film transistor having a substrate comprising the steps of forming source and drain electrodes having side surfaces facing each other over the substrate; forming an active layer over the source and drain electrodes and the substrate; forming a silicide layer on at least one of the side surfaces of the source and drain electrodes; forming a gate insulating layer on the active layer; and forming a gate electrode over the gate insulating layer.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
In the drawings:
FIGS. 1a and 1b are cross-sectional views showing a conventional method for fabricating a thin film transistor;
FIGS. 2a and 2b are cross-sectional views showing a method for fabricating a thin film transistor according to a first embodiment of the present invention;
FIG. 3 is a cross-sectional view of a thin film transistor according to a second embodiment of the present invention;
FIG. 4 is a cross-sectional view of a thin film transistor according to a third embodiment of the present invention;
FIG. 5 is a cross-sectional view of a thin film transistor according to a fourth embodiment of the present invention.
FIGS. 6a to 6e are cross-sectional views showing a method for fabricating a thin film transistor according to a fifth embodiment of the present invention; and
FIGS. 7a and 7f are cross-sectional views showing a method for fabricating a thin film transistor according to a sixth embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
FIGS. 2a and 2b are cross-sectional views showing a method for fabricating a thin film transistor according to a first embodiment of the present invention. As shown in FIG. 2a, a conductive layer is formed on a transparent insulating substrate 11 and patterned to form a gate electrode 12. Then, SiNx is deposited to form a gate insulating layer 13. A metal is deposited on the gate insulating layer 13 and patterned to form source and drain electrodes 14.
As shown in FIG. 2b, an amorphous silicon layer 15 is formed on the source and drain electrodes 14 and the exposed portion of the gate insulating layer 13, and patterned into a predetermined active layer pattern. Then, a heat treatment is carried out to form a silicide through a reaction of the silicon of amorphous silicon layer 15 with the metal which forms the source and drain electrodes 14. Thus, an ohmic contact layer 16 is formed. It is possible to form the silicide without the heat treatment, by heating the substrate during the formation of the amorphous silicon layer.
When aluminum (Al) is used as the metal to form the source and drain electrodes, the silicide is formed at a temperature of about 250° C. For chromium (Cr), the silicide is formed at a lower temperature of about 150° C.
Then, an indium tin oxide (ITO) layer is formed and patterned to form a pixel electrode 17 connected to one of the source and drain electrodes. A passivation layer 18 is formed on the overall surface of the substrate, completing the process.
It is also possible to form the silicide which serves as an ohmic contact layer during the formation of the ITO layer for forming the pixel electrode 17 or the protective (passivation) layer 18, without using a separate heat treatment. This is because the pixel electrode can be formed at a temperature that is adequate for forming the silicide as well.
FIG. 3 is a cross-sectional view of a thin film transistor according to a second embodiment of the present invention. This structure is formed similarly to the structure of the first embodiment. In the second embodiment, however, a passivation layer 18 is deposited before the ITO is formed. A contact hole is formed by selectively etching the passivation layer 18. Then, the ITO is deposited and patterned to form a pixel electrode 17. The pixel electrode 17 is connected to one of the source and drain electrodes through the contact hole.
Thus, the carrier transport path or the channel ("B" in FIG. 3) of the thin film transistor according to the present invention becomes shorter than that of the conventional thin film transistor (A in FIG. 1b). Accordingly, the operating gate voltage can be reduced and the characteristic of the device is improved. Moreover, an ohmic contact layer, silicide, is formed by reaction of the amorphous silicon of the active layer with the metal of the source and drain electrodes. Therefore, the present invention has a simple process.
FIG. 4 is a cross-sectional view of a thin film transistor according to a third embodiment of the present invention. This structure is formed similarly to the structure of the first embodiment. In the third embodiment, however, a gate insulating layer 13 is formed over an amorphous silicon layer 15, and a gate electrode 12 is formed over the gate insulating layer 13.
Referring to FIG. 4, a metal is deposited on a substrate 1 and patterned to form source and drain electrodes 14. An amorphous silicon layer 15 is formed on the source and drain electrodes 14 and patterned into a predetermined active layer pattern. As shown in FIG. 4, the amorphous silicon layer is also formed at respective sides of the source and drain electrodes 14. Then, a heat treatment is carried out to form a silicide through a reaction of the silicon of the amorphous silicon layer 15 with the metal forming the source and drain electrodes 14. Thus, an ohmic contact layer 16 is formed on as well as at respective sides of the source and drain electrodes 14.
A gate insulating layer 13 is formed and patterned on the amorphous silicon layer 13 and a gate electrode 12 is formed and patterned on the gate insulating layer 13.
An indium tin oxide (ITO) layer is formed and patterned to form a pixel electrode 17 connected to one of the source and drain electrodes 14. A passivation layer 18 is formed on the overall surface of the substrate, completing the process.
FIG. 5 is a cross-sectional view of a thin film transistor according to a fourth embodiment of the present invention. This structure is formed similarly to the structure of the third embodiment. In the fourth embodiment, however, a passivation layer 18 is deposited before the ITO is formed. A contact hole is formed by selectively etching the passivation layer 18. Then, the ITO is deposited and patterned to form a pixel electrode 17. The pixel electrode 17 is connected to one of the source and drain electrodes through the contact hole.
Accordingly, the present invention provides a thin film transistor and method for fabricating the same for facilitating charge transport between the source and drain by shortening the channel path and thus reducing the operating gate voltage.
FIGS. 6a to 6e are cross-sectional views showing a method for fabricating a thin film transistor according to a fifth embodiment of the present invention. As shown in FIG. 6a, a gate electrode 12 is formed on a substrate 11. A gate insulating layer 13 is formed on the gate electrode 12 and the substrate 11. A metal layer 14', such as Cr or Al, is formed on the gate insulating layer 13. An impurity-doped semiconductor layer 19', such as an n + -amorphous silicon layer, is formed on the electrode layer 14'.
As shown in FIG. 6b, the impurity-doped semiconductor layer 19' and the electrode layer 14' are simultaneously patterned to form source and drain regions 19, and source and drain electrodes 14, respectively.
As shown in FIG. 6c, a silicide layer 16" is formed at the interface between the source and drain regions 19 and source and drain electrodes 14. The silicide layer 16" can be formed by heat treatment, for example.
As shown in FIG. 6d, an active layer 15' is formed over the source and drain regions 19, and source and drain electrodes 14. The active layer 15' is formed of amorphous silicon, for example.
The silicide layer 16" can be formed simultaneously with the active layer 15' instead of having the separate heat treatment described above. Also, as stated in the description of the first embodiment of the present invention, the thin film transistor according to the present invention normally has an ITO layer for forming a pixel electrode, or a protective (passivation) layer. In this case, it is possible to form the silicide during the formation of the ITO layer for forming the pixel electrode or the protective (passivation) layer, without using a separate heat treatment.
After the step shown in FIG. 6d, it is possible to remove portions of the source and drain regions 19, and the silicide layer 16", using the active layer 15' as a mask. This exposes portions of the source and drain electrodes 14 as shown in FIG. 6e.
FIGS. 7a to 7f are cross-sectional views showing a method for fabricating a thin film transistor according to a sixth embodiment of the present invention. As shown in FIG. 7a, a gate electrode 12 is formed on a substrate 11. A gate insulating layer 13 is formed on the gate electrode 12 and the substrate 11.
As shown in FIG. 7b, a metal layer, such as Cr or Al, is formed on the gate insulating layer 13 and patterned to form source and drain electrodes 14.
As shown in FIG. 7c, an impurity-doped semiconductor layer 19' , such as an n + -amorphous silicon layer, is formed on the overall surface of the substrate 11 including the source and drain electrodes 14 and the gate insulating layer 13. Subsequently, heat treatment is carried out to form a silicide layer 16". After forming the silicide layer, the impurity-doped semiconductor layer 19' is removed, as shown in FIG. 7d.
As shown in FIG. 7e, an active layer 15' is formed over the silicide layer 16" and the source and drain electrodes 14. The active layer 15' is formed of, for example, amorphous silicon.
After the step shown in FIG. 7e, it is possible to remove portions of the silicide layer 16", using the active layer 15' as a mask, as shown in FIG. 7f This exposes portions of the source and drain electrodes 14.
It will be apparent to those skilled in the art that various modifications and variations can be made in the thin film transistor and method for fabricating the same of the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. | A thin film transistor includes a substrate, a gate electrode on the substrate, an insulating layer on the gate electrode, source and drain electrodes having side surfaces facing each other over the insulating layer, a carrier traveling path between the source and drain electrodes being shorter than a length of the gate electrode, an active layer over the source and drain electrodes and the insulating layer, and a silicide layer on at least one of the side surfaces of the source and drain electrodes. | 7 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention relates to online games, and more specifically, to processes for recommending friends based on habits for playing such online games.
[0003] 2. Background
[0004] Online games have recently gained popularity with Internet users. For example, a massively multiplayer online (MMO) game is an online computer game in which a large number of players interact with one another in a virtual world. MMO games are distinguished from single-player or small multi-player games by the game's persistent world, usually hosted by a game provider, which continues to exist and evolve even when the player is away from the game.
SUMMARY
[0005] The present invention provides for recommending game-playing friends based on a game player's habits for playing online games which promotes better playing experience for the game player.
[0006] In one implementation, a method of recommending game-playing friends or buddies is disclosed. The method includes: receiving at least one of playing habits, behaviors, and preferences of online game players; selecting a subset of the online game players matching a set number of criteria of the at least one of playing habits, behaviors, and preferences that are similar or complementary; and recommending the subset of the online game players selected as matching a set number of criteria as game-playing friends or buddies.
[0007] In another implementation, a system to recommend game-playing friends based on game player's habits for playing an online game is disclosed. The system includes: a game network configured to add game players logging into the game network to a list of players on the online game, the game network collecting playing habits of the game players; and a complex event engine configured to receive the list of players from the game network and the collected playing habits data from the storage unit, the complex event engine operating to process information including the list of players and the collected playing habits data to select a subset of the game players matching a set number of criteria including playing habits that are similar or complementary.
[0008] In a further implementation, a non-transitory tangible storage medium storing a computer program for recommending game-playing friends or buddies is disclosed. The computer program includes executable instructions that cause a computer to: receive at least one of playing habits, behaviors, and preferences of online game players; select a subset of the online game players matching a set number of criteria of the at least one of playing habits, behaviors, and preferences that are similar or complementary; and recommend the subset of the online game players selected as matching a set number of criteria as game-playing friends or buddies.
[0009] Other features and advantages of the present invention will become more readily apparent to those of ordinary skill in the art after reviewing the following detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a flowchart illustrating a technique for recommending game-playing friends based on game player's habits for playing online games in accordance with one implementation of the present invention.
[0011] FIG. 2 is a flowchart illustrating a process for selecting online game players matching a set number of criteria in accordance with one implementation of the present invention.
[0012] FIG. 3 shows a system model for recommending game-playing friends based on game player's habits for playing online games in accordance with one implementation of the present invention.
[0013] FIG. 4A illustrates a representation of a computer system and a user.
[0014] FIG. 4B is a functional block diagram illustrating the computer system hosting the buddy match system.
DETAILED DESCRIPTION
[0015] Certain implementations as disclosed herein provide for recommending game-playing friends based on a game player's habits for playing online games which promotes better playing experience for the game player. In one implementation, the recommendation is made to the game player. In another implementation, the recommendation is made to a game title which may pass the recommendation along to the game player at the game title's discretion. After reading this description it will become apparent how to implement the invention in various implementations and applications. However, although various implementations of the present invention will be described herein, it is understood that these implementations are presented by way of example only, and not limitation. As such, this detailed description of various implementations should not be construed to limit the scope or breadth of the present invention.
[0016] Although multiplayer online games have gained popularity with Internet users, an individual player may have difficulty convincing the player's real-world friends to play the games together because the friends may have significantly different schedules (e.g., time schedules) or skill levels (e.g., playing skills) to play the games with the player. In one implementation, game providers can track various “telemetry” data about habits, behaviors, and/or preferences of game players. The collected data may include time of day played, type of games played, interest of the player, clan membership of the player, type of friends in the real world, type of games owned or purchased, number of hours played, relationship to the player of the friend being recommended, and other similar data. The collected data can then be analyzed to recommend game playing friend(s) in the virtual world of the game with whom the player can play the games together. For example, a recommended online friend/buddy maybe someone who is often online at the substantially same times and/or has similar or complementary tastes for the games as the player.
[0017] In another implementation, to increase the likelihood of the player accepting the recommended “strangers,” a social graph showing how the recommended “strangers” are related to the player through the current/existing friends (e.g., showing the number of degrees of separation between the recommended “stranger” and the player) can be presented to the player. Thus, in this implementation, the data collected by the game provider would include information identifying a player such as name and age of the player and friends so that the connections can be made between substantially all players playing the games. Although some of the data to be collected by the game provider may already be available to the game provider, for this implementation, the game provider needs to further analyze and/or process the data to generate useful information such as a social graph for each individual player.
[0018] In one implementation, a process for generating a recommended friends list for a game player includes evaluating other players currently in an online game with the game player. Upon evaluation, players matching a set number of criteria would be recommended as potential friends or buddies.
[0019] FIG. 1 is a flowchart 100 illustrating a technique for recommending game-playing friends based on game player's habits for playing online games in accordance with one implementation of the present invention. In the illustrated implementation of FIG. 1 , playing habits of online game players are collected, at box 110 . As discussed above, various “telemetry” data about habits, behaviors, and/or preferences of game players can be collected by game providers. The collected data may include time of day played, type of games played, interest of the player, clan membership of the player, type of friends in the real world, type of games owned or purchased, number of hours played, relationship to the player of the friend being recommended, and other similar data. The collected playing habit data is received, at box 120 .
[0020] At box 130 , online game players matching a set number of criteria including playing habits that are similar or complementary are selected. In one implementation, the selection process involves evaluating players currently in an online game with the game player for whom the potential friends or buddies are being recommended. In another implementation, the selection process involves evaluating all online game players whose playing habits are available to the evaluator (e.g., a game provider). The collected data can then be analyzed to recommend game playing friend(s) in the virtual world of the game with whom the player can play the games together. For example, a recommended online friend/buddy maybe someone who is often online at the substantially same times and/or has similar or complementary tastes for the games as the player.
[0021] FIG. 2 is a flowchart illustrating a process 130 for selecting online game players matching a set number of criteria in accordance with one implementation of the present invention. The process includes inquiring, at box 200 , whether an online game player's favorite time of day at which the player mostly plays the game substantially matches the favorite playing time of the game player for whom the potential friends or buddies are being recommended. If the times substantially match, a match count is increased by a set number, at box 210 .
[0022] Another inquiry is made, at box 202 , whether types of games played by an online game player substantially matches or complements the types of games played by the game player for whom the potential friends or buddies are being recommended. If the types substantially match or complement each other, a match count is again increased by a set number, at box 212 . Another inquiry is made, at box 204 , whether general interests of an online game player substantially matches or complements the interests of the game player for whom the potential friends or buddies are being recommended. If the interests substantially match or complement each other, a match count is again increased by a set number, at box 214 . Another inquiry is made, at box 206 , whether clan memberships of an online game player substantially matches or complements the clan memberships the game player for whom the potential friends or buddies are being recommended. If the clan memberships substantially match or complement each other, a match count is again increased by a set number, at box 216 . Further inquiries using other factors can be made to determine the compatibility of the online game players with the game player for whom the potential friends or buddies are being recommended.
[0023] A determination is made, at box 208 , whether the match count kept at boxes 210 , 212 , 214 , 216 is greater than a preset number. If it is determined, at box 208 , that the match count is greater than a preset number, the online game player is recommended, at box 220 , as a potential friend or buddy. Otherwise, the online game player is not selected for recommendation. The process 130 is then repeated for a next online game player.
[0024] In general, the inquiries are made against the data already collected and stored for the online game players rather than inquiring each online game player as the player enters the game. However, the inquiries can be made real-time to collect the data directly from the online game player as the player enters the game.
[0025] Referring back to FIG. 1 , upon evaluation and selection, the selected players are recommended as potential game friends or buddies, at box 140 . Further, at box 150 , the selected players are accommodated for playing as game friends or buddies. In one implementation, accommodation involves presenting a list of recommended potential game friends or buddies when a player first logs in through an interface. As discussed above, to increase the likelihood of a particular player accepting the recommended “strangers” as online friends or buddies, a social graph showing how the recommended “strangers” are related to the particular player through the current and/or existing friends can be presented to the particular player. This also promotes brand loyalty since having active friends or buddies in the game keep game players around longer and lead to more downloadable content sales and recruitment of new players.
[0026] FIG. 3 shows a system model 300 for recommending game-playing friends based on game player's habits for playing online games in accordance with one implementation of the present invention. The system model 300 includes a game network 310 , a complex event processing (CEP) engine 320 , and a storage 330 including collected data.
[0027] In one implementation, when a particular player logs into a game network 310 , the network 310 adds the particular player to a list of players online in the game. The network 310 collects playing habits of online game players and stores the collected data in the storage 330 . As discussed above, in general, the playing habits are collected and stored in advance prior to the particular player logging into the game. However, the playing habits can be collected and/or updated when the particular player logs into the game. The collected data includes time of day played, type of games played, interest of the player, clan membership of the player, type of friends in the real world, type of games owned or purchased, number of hours played, relationship to the player of the friend being recommended, and other similar data such as games owned by the online game players.
[0028] The complex event engine 320 receives the list of players from the game network 310 and the collected playing habits data from the storage 330 . The complex event engine 320 then processes the information including the list and the data to select online game players matching a set number of criteria including playing habits that are similar or complementary. In one implementation, the complex event engine 320 and the storage 330 are coupled to the game network 310 . In another implementation, the complex event engine 320 and the storage 330 are configured to be included in the game network 310 . Upon processing and selection, the selected players are recommended as potential game friends or buddies 340 .
[0029] FIG. 4A illustrates a representation of a computer system 400 and a user 402 . The user 402 uses the computer system 400 to recommend game-playing friends based on a game player's habits for playing online games which promotes better playing experience for the game player. The computer system 400 stores and executes a buddy match system 490 .
[0030] FIG. 4B is a functional block diagram illustrating the computer system 400 hosting the buddy match system 490 . The controller 410 is a programmable processor and controls the operation of the computer system 400 and its components. The controller 410 loads instructions (e.g., in the form of a computer program) from the memory 420 or an embedded controller memory (not shown) and executes these instructions to control the system. In its execution, the controller 410 provides the buddy match system 490 as a software system. Alternatively, this service can be implemented as separate hardware components in the controller 410 or the computer system 400 .
[0031] Memory 420 stores data temporarily for use by the other components of the computer system 400 . In one implementation, memory 420 is implemented as RAM. In one implementation, memory 420 also includes long-term or permanent memory, such as flash memory and/or ROM.
[0032] Storage 430 stores data temporarily or long term for use by other components of the computer system 400 , such as for storing data used by the buddy match system 490 . In one implementation, storage 430 is a hard disk drive.
[0033] The media device 440 receives removable media and reads and/or writes data to the inserted media. In one implementation, for example, the media device 440 is an optical disc drive.
[0034] The user interface 450 includes components for accepting user input from the user of the computer system 400 and presenting information to the user. In one implementation, the user interface 450 includes a keyboard, a mouse, audio speakers, and a display. The controller 410 uses input from the user to adjust the operation of the computer system 400 .
[0035] The I/O interface 460 includes one or more I/O ports to connect to corresponding I/O devices, such as external storage or supplemental devices (e.g., a printer or a PDA). In one implementation, the ports of the I/O interface 460 include ports such as: USB ports, PCMCIA ports, serial ports, and/or parallel ports. In another implementation, the I/O interface 460 includes a wireless interface for communication with external devices wirelessly.
[0036] The network interface 470 includes a wired and/or wireless network connection, such as an RJ-45 or “Wi-Fi” interface (including, but not limited to 802.11) supporting an Ethernet connection.
[0037] The computer system 400 includes additional hardware and software typical of computer systems (e.g., power, cooling, operating system), though these components are not specifically shown in FIG. 4B for simplicity. In other implementations, different configurations of the computer system can be used (e.g., different bus or storage configurations or a multi-processor configuration).
[0038] The above description of the disclosed implementations is provided to enable any person skilled in the art to make or use the invention. Various modifications to these implementations will be readily apparent to those skilled in the art, and the generic principles described herein can be applied to other implementations without departing from the spirit or scope of the invention. Accordingly, additional implementations and variations are also within the scope of the invention. For example, the illustrated implementations discuss collecting and processing game player's habits for playing online games to recommend game-playing friends. However, in other implementations, habits, behaviors, and/or preferences of users in general can be collected and processed in similar techniques as described above to provide other services such as advanced matchmaking for marriage, roommates, and other endeavors needing compatibility. Further, it is to be understood that the description and drawings presented herein are representative of the subject matter which is broadly contemplated by the present invention. It is further understood that the scope of the present invention fully encompasses other implementations that may become obvious to those skilled in the art and that the scope of the present invention is accordingly limited by nothing other than the appended claims.
[0039] Additionally, the steps of a method or technique described in connection with the implementations disclosed herein can be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium including a network storage medium. An example storage medium can be coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium can be integral to the processor. The processor and the storage medium can also reside in an ASIC. | Recommending game-playing friends or buddies, including: receiving at least one of playing habits, behaviors, and preferences of online game players; selecting a subset of the online game players matching a set number of criteria of the at least one of playing habits, behaviors, and preferences that are similar or complementary; and recommending the subset of the online game players selected as matching a set number of criteria as game-playing friends or buddies. Keywords include improved game experience, social building, and community growing. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Priority is claimed to European Patent Application No. EP 11 172 830.9, filed Jul. 6, 2011, the disclosure of which is incorporated herein by reference, in its entirety.
AREA OF THE INVENTION
The present invention concerns a device and a method for surveying jet grouting piles in the ground, which is suitable for a drilling and grouting linkage assembly for creating a hole, and a jet grouting pile in the region of the hole.
PRIOR ART
The method for producing jet grouting piles is a method of special excavation in which an energy-rich, high pressure jet of water and/or binder emerges from a rotating drilling and grouting linkage assembly and thus destroys the stratification of the surrounding soil and turns it into mortar by the addition of binder. In this context it is desirable to monitor the quality of the jet grouting pile and hence the work result. For this there is a possibility of providing a measuring device during processing, for example on the drilling and grouting linkage assembly.
A known drilling and grouting linkage assembly with a measurement device is disclosed in European Patent Application EP 1 974 122 A1 (published as WO2007/101500 and US2009178849 A1). The known device comprises a drilling and grouting linkage assembly to create a hole and a jet grouting pile in the region of the drilling hole, and a measurement device for surveying the jet grouting pile, wherein this measurement device is at least partly integrated in the drilling and grouting linkage assembly. With such a device it is possible to monitor the quality of the jet grouting piles in a flexible and reliable manner during operation of the drilling and grouting linkage assembly.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a measuring device for assessing a jet grouting pile which is easier to handle than the prior art and in particular takes up less space.
The above and other objects are achieved by a measurement device adapted for integration in a drilling and grouting linkage assembly used to create a hole and a jet grouting pile in a region of the hole, wherein the measurement device is used for surveying the jet grouting pile. The measurement device includes: a hollow body; a retraction and extension housing mounted on the hollow body; and a scanning element movable from a retracted position into an extended position and being deflectable inside the measurement device through the retraction and extension housing, wherein the scanning element includes a rod or cable and a sensor attached at an end of the cable or rod, wherein the rod or cable at least in segments comprises a shape-memory alloy.
In an embodiment, the sensor has properties preferred for the required use and the scanning element is advantageously integrated and guided in the drilling and grouting linkage assembly.
In one embodiment, a measurement device is provided for a drilling and grouting linkage assembly. The drilling and grouting linkage assembly is intended to create a hole and a jet grouting pile in the region of the hole. This means that with the drilling and grouting linkage assembly, first a hole is made in the subsoil/soil, and the soil is softened at a suitable depth (jet grouting pile).
The measuring device according to the invention is also intended for surveying a jet grouting pile, in particular for measuring the diameter of the jet grouting pile, and the measuring device is integrated in the drilling and grouting linkage assembly. Furthermore the measurement device has a scanning element including a sensor, that can move from a retracted position to an extended position, and is deflected within an extension and retraction housing fitted on the measurement device. According to an embodiment, the rod or cable of the scanning element comprises at least in segments a shape-memory alloy. Preferably this is a metal alloy of nickel titanium. A variant of this metal alloy is known under the name Nitinol. Such materials surprisingly have advantageous properties for use in excavation/special excavation work. The scanning element is flexible for deflection but outside the measurement device, i.e. within the jet grouting pile, resists the external conditions and can thus guide the sensor into the jet grouting pile for measurement.
In a further embodiment the scanning element can be deflected by an angle of substantially 90°. This has the advantage that the scanning element is guided within the drilling and grouting linkage assembly and can be moved laterally out of the drilling and grouting linkage assembly.
The sensor of the scanning element can be a pressure and/or tilt sensor. Furthermore with such a sensor the diameter of the jet grouting pile can be determined, wherein the tilt sensor can ensure a valid measurement. The sensor may comprise several combined individual sensors. However in an alternative embodiment it is possible that measurement is performed with the scanning element and a further device in order to assess the jet grouting pile. In particular on extension of the scanning element, by monitoring the motor power it can be established when the scanning element has reached the wall of the jet grouting pile: if the current consumption of the motor increases and at the same time no increase is established in the extended length of the scanning element, then the scanning element has reached the wall of the jet grouting pile.
The measures described for detection and evaluation of the jet grouting pile can also be used in combination with each other.
The scanning element including the sensor may be retracted and extended in operation of the device according to the invention through the opening of the retraction and extension housing mounted on the measurement device. In one embodiment the sensor is designed, amongst others dimensioned, such that it seals the opening of the retraction and extension housing in the retracted state.
In a further embodiment of the measurement device, rollers are provided inside the measurement device which deflect the scanning element. The rollers provide a safe deflection with little susceptibility to error, wherein on transport over the rollers, the scanning element is not substantially changed externally (i.e. for example not deformed).
In a further embodiment the scanning element is sealed in relation to the drilling and grouting linkage assembly. However the scanning element is protected inside the drilling and grouting linkage assembly against dirt and contamination which can cause friction on movement.
In particular a flushing channel can be provided in the retraction and extension housing through which the scanning element can be flushed with water or a suspension on retraction and extension. This facilitates the sealing process and ensures that no contaminants can enter the drilling and grouting linkage assembly.
In a further variant of the measurement device, a drive device is provided in this with which the scanning element can be driven. The force may be applied in the region of the deflection of the scanning element. This guarantees safe retraction and extension of the scanning element into and out of the measurement device.
In another embodiment, the scanning element may be curved before its deflection. This pre-curvature can, for example, be provided with the first roller in the region of the deflection. Thus the scanning element is not deflected directly in the direction which leads to the outlet point of the scanning element from the measurement device, but against this direction. This facilitates the movement of the scanning element and under certain circumstances a greater deflection radius can be achieved within the measurement device when the scanning element is pre-curved further towards the wall of the measurement device. This pre-curvature also achieves the stabilisation of the scanning element.
The cable portion of the scanning element may comprise a nickel titanium alloy, for example an alloy known under the name of Nitinol. This is particularly suitable for the required properties for the scanning element.
Furthermore the present invention comprises a drilling and grouting linkage assembly to create a hole, wherein the drilling and grouting linkage assembly has a nozzle device and attached thereto a measurement device according to one of the variants described above. Furthermore a drill bit can be attached to the measurement device, in particular via an adapter mounted in between. A hole is created with the drill bit and the nozzle device may be used to form a jet grouting pile.
As well as the measurement device according to the invention and the drilling and grouting linkage assembly comprising this measurement device, the present invention also comprises a method for measuring a jet grouting pile. This method can be carried out in one embodiment with a measurement device according to the invention or with the drilling and grouting linkage assembly according to the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is described below with reference to a preferred embodiment. This embodiment is explained in detail in the context of the attached drawings.
FIG. 1 shows an overall view of a drilling and grouting linkage assembly with a measurement device according to the invention mounted on a drill.
FIG. 2 is a functional view of the drilling and grouting linkage assembly with a drill bit, the nozzle device, adapter and measurement device.
FIG. 3 shows an enlarged view of the region of the drilling and grouting linkage assembly of FIG. 1 in which the measurement device and the jet grouting nozzle are shown enlarged.
DETAILED DESCRIPTION
FIG. 1 shows diagrammatically an overall view of a drilling and grouting linkage assembly 1 . The drilling and grouting linkage assembly 1 here is mounted on a mobile machine 2 and in the depiction in FIG. 1 already introduced into the ground. At a particular depth, using a nozzle device described later, a jet grouting pile D is introduced into the soil. Here the original stratification of the soil is changed by the energy-rich, high pressure jet and at the same time or with a time delay it is filled with a suspension so that underground reinforcement bodies are produced which can be used as sealing elements or as supporting elements or as sealing and supporting elements.
FIG. 2 shows a functional view of a drilling and grouting linkage assembly 1 . This comprises various segments, namely a connecting segment 11 , an intermediate segment 12 , a nozzle device 13 , a measuring device 14 , an adapter 15 and a drill bit 16 . These elements are arranged in the corresponding order and connected by threaded connectors. FIG. 3 shows in detail the threads 7 , 8 , 9 and 10 between the segment 12 , the nozzle device 13 , the measurement device 14 , the adapter 15 and the drill bit 16 . A high pressure suspension line 3 for the high pressure suspension, a line 4 for air and a line 5 for the drill flusher are routed to the drilling and grouting linkage assembly 1 .
At the connection of the line 3 for the high pressure suspension is provided a bearing/seal 100 . On an attachment 101 to line 4 is also provided a bearing/seal 102 and a further bearing/seal 103 . The line 5 for the drill flusher is mounted on an attachment 104 with a 2″ hose connection 105 . Furthermore a bearing/seal 106 is provided between attachment 104 and the drilling and grouting linkage assembly 1 , in particular segment 11 .
FIG. 3 shows part of the nozzle device 13 mounted on segment 12 and measuring device 14 in detail. The nozzle device 13 and the measuring device 14 are coupled detachably together in this embodiment by a screw connection 8 .
The nozzle device 13 is intended for application under high pressure of a high pressure suspension supplied via a high pressure line 3 . The working fluid for supporting the high pressure suspension is preferably air, which is supplied through a further line 4 .
In the present embodiment screw connections 7 to 10 are provided. Sealing rings ensure that no contaminants enter the measuring device 14 for example during operation. As an alternative to the screw connections 7 to 10 , individual radially acting bolts can be provided with which for example the measurement device 14 is bolted to the nozzle device 13 . Other plug connections are also conceivable.
Guided in the measurement device 14 is a scanning element 40 comprising a rod or cable 40 b and a sensor 40 a attached an end of the rod or cable, the sleeve of which rod or cable in the present embodiment comprises a nickel titanium alloy. This nickel titanium alloy belongs to the group of shape-memory alloys and is known under the name Nitinol. Usually such materials are used in the field of medical technology. However in the present development work it was found that Nitinol is surprisingly suitable also for devices which are used in the field of excavation or special excavation work.
The scanning element 40 is guided parallel to the high pressure suspension line 3 and accommodated in the measurement device 14 . For this in a region of the measurement device 14 pointing towards the nozzle device 13 , a motor 41 is provided with which the scanning element 40 can be driven. The drive force is transmitted via a drive roller 41 a to the scanning element 40 .
Furthermore the scanning element 40 in the region of the measurement device is deflected from a vertical direction into horizontal direction. “Vertical” in the sense of the present application means a direction along the drilling and grouting linkage assembly 1 whereas a “horizontal” direction is oriented perpendicular to this.
Several rollers 42 are provided inside the measurement device 14 such that the scanning element 40 is guided substantially at an angle of 90° in relation to the guide parallel to the high pressure suspension channel 3 . In this context FIG. 2 shows that before deflection of the scanning element 40 , a pre-curvature is produced, namely before the first roller 42 in the feed direction. In this way the deflection of the scanning element 40 by an angle of 90° which takes place later in the advance direction can be set better in the measurement device.
After the scanning element 40 inside the measurement device 14 has been brought from the vertical direction (path within the nozzle device 13 ) into a substantially horizontal direction, the scanning element 40 extends through a retraction and extension housing 43 . The refraction and extension housing 43 has a sealing element 45 which seals the inside of the measurement device 14 against the outside.
Furthermore the sensor element 40 a mounted at one end of the rod or cable 40 b is formed such that it can lie against the opening of the retraction and extension housing 43 and thus alternatively or additionally to the sealing element 45 provide a seal against the inside of the measurement device 14 .
The movement of the scanning element 40 in the present embodiment is initiated by means of motor 41 in the region of the deflection of the scanning element 40 . Where applicable, alternatively or additionally, individual rollers 42 can also be driven. Furthermore in the region of the drilling and grouting linkage assembly, further integrated motors can be provided. The drives are excited for example via the battery operation of the measurement system.
For measurement the scanning element 40 is moved away from the sealing device 45 and enters the horizontal direction, and is introduced into the jet grouting pile not yet hardened. For example the scanning element 40 can be extended up to 2 m out of the sealing device. The inherent rigidity of the scanning element 40 and the support from the sealed rod allows it to maintain a substantially horizontal direction even outside the measurement device 14 .
Initialisation of the measurement process using the scanning element takes place by means of body-borne sound pulses which are initiated in the drilling and grouting linkage assembly 1 or by radio transmission. The steps for surveying a jet grouting pile in the ground can then take place as follows. In a first step a suitable drill contact point is established. In a further working step the drilling and grouting linkage assembly 1 is brought to the new drill contact point and then the drilling and grouting linkage assembly 1 is lowered to a desired depth by means of drilling, wherein accompanying the drilling, the hole course can be measured by the integral tilt sensors.
After reaching the desired drilling depth, a jet grouting pile is created in the region of the hole and the diameter of the jet grouting pile produced is measured at different heights. The scanning element 40 is moved in the jet grouting pile which has not yet hardened. The scanning element 40 is advantageously designed so that because of the drive, its inherent rigidity, its own weight and the lift, it can be held substantially horizontally. The data detected and stored by the scanning element 40 can be read in parallel to measurement or with a time delay on raising of the drilling and grouting linkage assembly from the hole. From this data, concrete information can be obtained on the composition of the soil and the resulting composition of the jet grouting pile produced. These results can be used for further calculations.
When measurement has been carried out, the scanning element 40 on retraction into the measurement device 14 is flushed with water pressure via the flushing channel 45 provided on the retraction and extension housing 43 , and during retraction sealed against the liquid medium in the hole and the pile. The water flushing before the retraction and extension housing 43 thus facilitates the sealing process and ensures that no contamination can penetrate inside the measurement device 14 .
The drill bit 16 can for example be connected directly to the measurement device 14 . Alternatively as shown in the present embodiment, an adapter 15 can be provided between the measurement device 14 and the drill bit 16 . Instead of an adapter 15 , several elements can also be provided between the measurement device 14 and the drill bit 12 .
The drill bit 16 has openings 61 for a drill flusher. From these openings 61 a fluid emerges from the drill bit and thus allows penetration of the drilling and grouting linkage assembly 1 into the ground/soil. | A device and a method for surveying jet grouting piles in a subsoil, which is suitable for a drilling and grouting linkage assembly for creating a hole and a jet grouting pile in a region of the hole. A measurement device is integrated in the drilling and grouting linkage assembly and comprises a scanning element that is movable from a retracted position to an extended position. The scanning element is deflected inside the measurement device through a retraction and extension housing mounted on the measurement device. The scanning element comprises at least in segments a shape-memory alloy. | 4 |
FIELD OF THE INVENTION
This invention pertains to the treatment of cellulosic pulp and in particular to a reactor system and a method for removing lignin or color from virgin or secondary pulp by reaction with oxygen or ozone.
BACKGROUND OF THE INVENTION
Oxygen delignification is a well-known process for removing lignin from wood pulp by treatment with oxygen and alkali followed by washing to remove soluble oxygen-lignin reaction products. The oxygen delignification reactions are typically carried out by mixing oxygen with medium consistency, heated alkaline pulp and passing the resulting mixture through a reactor with a sufficient contact time to allow the reaction to proceed to the desired degree. One type of reactor used for delignification is a vertical upflow reactor in which the pulp-oxygen mixture is introduced into the bottom of the reactor, flows upward while the reactions take place, and treated pulp is withdrawn from the top of the reactor.
The reactor feed mixture can be prepared by methods known in the art. U.S. Pat. No. 4,886,577 discloses the use of a specifically-designed centrifugal pump in which a pulp slurry is degassed by vacuum while passing through the pump, followed by addition of oxygen directly into the pulp at the pump discharge utilizing a shear plate or an oxygen permeable material which causes the oxygen to be introduced as small bubbles. South African Patent Application 868664 describes an alternate method to introduce oxygen into pulp which comprises passing the heated pulp in a completely fluidized state through an unobstructed flow path where it is contacted with highly dispersed oxygen bubbles ranging from 2 to 10 microns in diameter. This patent application also summarizes earlier alternative methods for oxygen dispersion described in the prior art. Australian Patent Application 22021/88 describes a similar method for introducing oxygen or oxygen-steam mixtures into the pulp.
In oxygen delignification at temperatures typically in the range of 80° to 120° C., the amount of oxygen required for delignification is much larger than the amount of oxygen soluble in the liquor associated with a given amount of pulp. In order to supply sufficient oxygen for delignification in the reactor, it is therefore necessary to incorporate bubbles of free oxygen gas in the pulp introduced to the reactor. It is desirable that these bubbles be very small in order to maximize the interfacial area so that additional oxygen can dissolve in the liquor as dissolved oxygen is consumed in the delignification reactions. The reactor system should be designed to achieve a constant upward flow velocity at all radial locations in the reactor, i.e., plug flow. Deviations from plug flow, in which some portions of the pulp move at a higher velocity and thus have less residence time in the reactor than other portions of the pulp, will cause uneven delignification and poor product quality. Careful design of the inlet and outlet sections of the reactor is necessary, since both sections influence pulp flow distribution throughout the reactor.
U.S. Pat. No. 5,034,095 discloses an upflow reactor for oxygen delignification comprising a cylindrical vessel having conical chambers connected to the inlet (bottom) and outlet (top) of the reactor wherein pulp is introduced and withdrawn at the axial center of the respective conical chambers. The convergence angle of each conical chamber, also defined as the included angle, is less than 60 degrees, preferably 20-60 degrees. No device to aid in pulp distribution or withdrawal is used in either the inlet chamber or the outlet chamber. This patent also describes a type of prior art reactor which utilizes a rotating mechanical distributor at the inlet and a mechanical discharge device at the outlet to aid in distribution and withdrawal of pulp from the reactor. These mechanical devices, which are widely used in commercial reactor systems, are effective for pulp feed distribution and withdrawal but can increase capital and maintenance costs for such reactor systems.
Improved reactor designs for oxygen delignification are desirable to achieve consistent product homogeneity and minimize the capital and operating costs of the reactor system. Such designs should emphasize operating simplicity and minimize complex design features. The reactor system of the present invention described and claimed below satisfies these requirements and offers improvements over prior art reactor systems.
SUMMARY OF THE INVENTION
The present invention is a reactor system for the chemical treatment of cellulosic pulp comprising one or more reactors, wherein each reactor includes a vertical, cylindrical vessel having a lower end and an upper end, a frusto-conical bottom chamber joined at the base to the lower end of the vessel, and piping means for introducing a mixture of untreated cellulosic pulp and treatment chemicals axially into the bottom chamber. Oxygen and ozone are preferred treatment chemicals. A distributor comprising a cone is located coaxially within the bottom chamber; the vertex of the cone is oriented downward, and the distributor operates in conjunction with the bottom chamber to promote flow of the pulp-oxygen mixture upward through the cylindrical vessel at a constant velocity. A head connected to the upper end of the cylindrical vessel includes means for withdrawing treated cellulosic pulp from the reactor system which comprises a plurality of regularly placed nozzles for injecting liquid to dilute the pulp for easy withdrawal. The feed distributor at the lower end and the withdrawal means at the upper end of the reactor operate in combination to maintain plug flow of pulp and oxygen through the reactor, thus ensuring even delignification and a homogeneous product. The feed distributor allows quiescent flow of pulp and dispersed oxygen, thus eliminating the potential for oxygen bubble coalescence caused by mechanical distribution devices.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional isometric drawing of the reactor of the present invention.
FIG. 2 is a sectional drawing of the upper portion of the reactor of the present invention.
FIG. 3 is a top view of the reactor of the present invention showing a portion of the head and nozzles.
FIG. 4 is a cross-sectional view of a nozzle in the head of the reactor of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The invention is a reactor system for the chemical treatment of cellulosic pulp as shown in the sectional isometric drawing of the reactor portion of the system shown in FIG. 1. Cylindrical vessel 1 is equipped with frusto-conical bottom chamber 3 in which inverted cone 5 is located coaxially near the small end of the bottom chamber. Vessel 1 has a length to diameter ratio L 1 /D 1 between about 5 and 10, preferably between about 6.5 and 8.0. Cone 5 is a solid cone attached to the inner surface of bottom chamber 3 by at least two brackets 7 and 9; preferably three or more brackets are used. Flanged opening 11 is attached to the small end of the bottom chamber and serves as the pulp inlet. Angle a 1 is between about 30 and 45 degrees, so that the included angle or convergence angle of the frusto-conical bottom chamber is between about 60 and 90 degrees, preferably about 70 degrees. The included angle of cone 5 is generally equal to the included angle of bottom chamber 3, and cone 5 is preferably located near the inlet of bottom chamber 3 but may be located at any point along axis 13 within bottom chamber 3. The diameter d of the base of cone 5 and L 2 , the axial distance between the bases of cone 5 and bottom chamber 3, are selected such that the ratio L 2 /d is between about 3 and 7, preferably between about 4.2 and 5.4. Perpendicular distance b between the walls of bottom chamber 3 and cone 5 is fixed by the values of L 2 and d, and is preferably between about 200 and 300 mm depending upon diameter D 1 of cylindrical vessel 1. The ratio of the vessel diameter D 1 to the cone base diameter d is between about 4 and 10, preferably between about 6 and 8.
The combined bottom chamber 3 and cone 5 serve as the distributor for pulp and treating chemicals entering the reactor through flanged opening 11. When the treating chemicals include highly dispersed bubbles of reactive gases such as oxygen or ozone, it is highly desirable that these bubbles remain small; the reactor system therefore should be designed to minimize bubble coalescence, since larger bubbles have less interfacial area and can promote undesirable channelling in the reactor. The design of bottom chamber 3 and cone 5 allows the flow and distribution of pulp into the reactor with minimum disturbance, thereby minimizing bubble coalescence.
Head 15 having a generally ellipsoidal or dished shape is attached to the upper end of vessel 1 and includes a concentric flanged outlet 17 for removal of treated pulp and a plurality of nozzles 19 for injecting a suitable aqueous liquid, such as for example washer filtrate, into the pulp to reduce pulp consistency which aids pulp withdrawal and eliminates plugging. The generally ellipsoidal or dished shape of the head is selected based on typical pressure vessel design practices as known in the art. The liquid is supplied at the necessary pressure by known pumping means. Nozzles 19 project through head 15 and are installed at angles to the surface of head 15 as illustrated in FIG. 1. The inside diameter D 6 of each nozzle is typically between about 30 and 70 mm, and each nozzle extends into head 15 a distance of between about 100 and 300 mm. The ratio D 6 /D 1 between the inside diameter of each nozzle and the diameter of vessel 1 is typically between about 0.008 and 0.020. The angled orientation of nozzles 19 serves to impart a moderate degree of beneficial circular or swirling motion to the pulp during withdrawal through outlet 17. Nozzles 19 are preferably installed in one or more circular patterns concentric with the axis of vessel 1, wherein the nozzles on a given circular pattern are equally spaced on the pattern. At least eight nozzles are generally preferred, but any reasonable number may be installed as needed. Typically 16 nozzles are installed in two circular patterns as illustrated in FIG. 1.
Nozzles 19 are oriented relative to head 15 as illustrated in FIG. 2, and section 4--4 is presented in FIG. 4. Angle a 2 is between about 25 and 65 degrees, preferably about 45 degrees, as measured between tangent 25 and axis 21 of specific nozzle 23. Tangent 25 is a line drawn tangent to the circle formed by the circular pattern at the location of nozzle 23, or more specifically at the intersection 27 of axis 21 and the circle formed by the circular pattern of nozzles. Because of the curvature of head 15, a second angle must be defined to fix the exact orientation of each nozzle. FIG. 3, which is a top sectional view of head 19, illustrates angle a 3 formed by axis 21 of nozzle 23 and radial line 29; this angle is less than 90 degrees and greater than 45 degrees, and depends upon the radial distance of the nozzle from the axis of vessel 1. Radial line 29 is a radial line drawn perpendicularly from the axis of vessel 1 through point 27 of FIG. 4. All nozzles are angled to discharge in the same general circumferential direction as illustrated in FIG. 1.
The diameters D 2 and D 3 of inlet 11 and outlet 17 respectively are selected relative to vessel diameter D 1 such that the ratios D 2 /D 1 and D 3 /D 1 are between about 0.12 and 0.20. The diameters D 4 and D 5 of the circular patterns of nozzles 19 are typically selected such that the ratios D 4 /D 1 and D 5 /D 1 are between about 0.3 and 0.8. Bottom chamber 3 and cone 5 act in combination with the dilution nozzles in the reactor head to ensure even plug flow of the pulp upward through the reactor, which in turn ensures a highly homogeneous pulp product.
The reactor described above is useful for the treatment of any type of cellulosic pulp including virgin pulp prepared from wood chips or secondary pulp prepared from waste paper material. The pulp can be prepared by means well-known in the art, and can be subjected to prior process steps such as disintegration, screening, delignification by sulfate or other chemical processes, and other known steps. Pulp entering the reactor therefore comprises cellulosic fibers containing lignin and/or other color-causing materials, water, soluble treatment chemicals such as soluble alkaline compounds, and optionally dispersed oxygen, ozone, or other reactive gases. Certain types of secondary pulp may also contain contaminants such as binders, polymers, polymeric inks, adhesives, and the like. When oxygen is used for treating virgin pulp, the oxygen reacts with lignin to form reaction products removable in succeeding washing steps. When oxygen is used for treating pulp prepared from waste paper material, lignin and/or color bodies and/or other contaminants react with the oxygen to form suspended and/or soluble reaction products removable in subsequent washing, screening, or deinking steps. The reactor of the present invention may be used in a single stage configuration, or may be used in two or more stages for series treatment of pulp at different process conditions.
The reactor of the present invention is particularly useful in medium consistency (5 to 20%, preferably 8 to 14% consistency) oxygen delignification in which oxygen is dispersed as fine bubbles in the pulp prior to entering the reactor. In oxygen delignification, it is important that the small oxygen bubbles remain dispersed while the pulp flows upward through the reactor during which the oxygen dissolves in the liquor and reacts with the lignin or other color-causing materials to yield reaction products which are washed from the pulp in subsequent steps. Oxygen dosage is typically 0.1 to 5 wt % on oven-dried pulp. The feed distribution achieved by bottom chamber 3 and cone 5 allows quiescent flow of pulp and dispersed oxygen into the reactor, thus eliminating the potential for oxygen bubble coalescence which could be caused by mechanical distribution devices. Pulp reactor residence time for oxygen bleaching is typically between about 45 and 60 minutes. For ozone bleaching, reactor residence times range from 0.5 to 10 minutes; dosage is typically between 0.05 and 1.0 wt % on oven-dried pulp.
Removal of treated pulp is accompanied by the injection of an aqueous liquid, such as for example washer filtrate, through nozzles 19 at a suitable flow rate to dilute the pulp such that the ratio of the consistency after dilution to the consistency before dilution is between about 0.5 to 0.75. For example, a pulp with a consistency of 12% would be diluted to a consistency of between 6 and 9% prior to withdrawal from the reactor. This liquid injection also induces a moderate degree of beneficial circular or swirling motion to the pulp during withdrawal through outlet 17. The dilution of the pulp upon withdrawal serves two purposes: first, it ensures even flow distribution of the pulp through the reactor in conjunction with bottom chamber 3 and cone 5, and second, it eliminates the possibility of plugging when withdrawing pulp through the reactor head 15 and outlet 17. The liquid injected through nozzles 19 provides an excellent means for the introduction of additional treating chemicals such as surfactants, enzymes, acids, chelants, or other compounds if required in downstream process steps.
EXAMPLE
The application of the reactor system described above to medium consistency oxygen delignification is illustrated by the following Example. Steam and alkali are added to 1100 metric tons/day of medium consistency kraft pulp at the suction of a Kaymr MC Model 15 pump. Oxygen is injected into the discharged pulp by means of porous diffusers. The oxygenated pulp is reheated by steam injection to 92° C. and flows into the reactor of FIG. 1 at a pressure of 121 psig through bottom chamber 3 by which it is distributed into reaction vessel 1. At this point, the pulp has a consistency of 12.0%, a pH of 12.5, a Kappa no. of 15, and contains 15 kg of oxygen per metric ton of air dried pulp. The mixture of pulp, alkali, and oxygen flows upward through the reactor at a residence time of 50 minutes. At the top of the reactor but prior to dilution, the pulp temperature is 95° C. due to the exothermic delignification reaction and the pressure is 60 psig. Pulp filtrate is injected through 16 nozzles, each 38 mm I.D., in the reactor head as illustrated in FIG. 1 to dilute the pulp is a consistency of 7.5%, which cools the diluted pulp to 85° C., and the pulp is withdrawn through discharge pipe 17. The delignified pulp, which now has a Kappa no. of 90, is ready for washing and bleaching prior to the final papermaking step.
The reactor of the present invention differs from prior art reactors and has several unique features and advantages over such reactors. First, the present reactor utilizes no mechanical devices for pulp feed, distribution, or discharge. This reduces capital and operating costs, and also introduces no agitation which could cause the small, dispersed oxygen bubbles to coalesce. As earlier described, coalescence is undesirable because it reduces the oxygen gas interfacial area, thus reducing the oxygen dissolution rate and therefore the delignification rate. In addition, large oxygen bubbles in the reactor may induce channeling resulting in a nonhomogeneous product. The reactor also differs from the reactor described in earlier-cited U.S. Pat. No. 5,034,095 which utilizes conical top and bottom reactor sections having convergence angles between 20 and 60 degrees, in contrast to the conical bottom chamber of the present invention which has a convergence angle greater than 60 and less than 90 degrees. These conical sections in U.S. Pat. No. 5,034,095 are essentially open and contain no distribution or discharge devices.
The reactor system of the present invention, which utilizes the unique combination of a simple conical inlet distributor and dilution prior to discharge allows the controlled processing of cellulose pulp at uniform plug flow reactor conditions and eliminates the possibility of plugging during pulp discharge. The system can be used for delignification of virgin pulp or for the removal of color-causing contaminants in pulp prepared from waste paper materials, and is particularly useful in the treatment of such pulps with oxygen.
The essential characteristics of the present invention are described completely in the foregoing disclosure. One skilled in the art can understand the invention and make various modifications thereto without departing from the basic spirit thereof, and without departing from the scope and range of equivalents of the claims which follow. | A reactor system is disclosed for the treatment of cellulosic pulp in which pulp is distributed upward through a vertical reactor using a unique conical distributor and is discharged using a unique dilution method to eliminate plugging. The system is particularly useful for delignifying virgin wood pulps or decolorizing pulps made from waste paper materials. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates to a method for the preparation and purification of fatty acids which are homologues of conjugated linoleic acids, from materials rich in alpha or gamma linolenic acids. The method permits the transformation of approximately over two thirds of a-linolenic acid (9Z,12Z,15Z-octadecatrienoic acid) into 9Z,11E,15Z-octadecatrienoic acid and 9Z,13E,15Z-octadecatrienoic acid. Enrichment up to and over 40% is readily performed with urea crystallization. Moreover, the product can be produced in over 90% purity by simple preparative liquid chromatography. The reaction is unique in that the reaction produces the above mentioned conjugated trienoic acids with a high selectivity, in a short time period and in relatively mild conditions. The reaction also transforms gamma-linolenic acid (6Z,9Z,12Z-octadecatrienoic acid) into 6Z,8E,12Z-octadeccatrienoic acid and 6Z,10E,12Z-octadecatrienoic acid. In all cases, geometrical isomers and fully conjugated isomers are also produced.
BACKGROUND OF THE INVENTION
[0002] Processes for the conjugation of the double bonds of polyunsaturated unconjugated fatty acids have found their main application in the field of paints and varnishes. Oils comprised of triglycerides of conjugated fatty acids are known as drying oils. Drying oils have value because of their ability to polymerize or “dry” after they have been applied to a surface to form tough, adherent and abrasion resistant films. Tung oil is an example of a naturally occurring oil containing significant levels of fully conjugated fatty acids. Because tung oil is expensive for many industrial applications, research was directed towards finding substitutes.
[0003] In the 1930's, it was found that conjugated fatty acids were present in oil products subjected to prolonged saponification, as originally described by Moore (J. Biochem., 31: 142 (1937)). This finding led to the development of several alkali isomerization processes for the production of conjugated fatty acids from various sources of polyunsaturated fatty acids.
[0004] The positioning of the double bonds in the hydrocarbon chain is typically not in a conjugated, i.e., alternating double bond-single bond-double bond, manner. For example, α-linolenic acid is an eighteen carbon acid with three double bonds (18:3) at carbons 9, 12 and 15 in which all three double bonds have the cis configuration, i.e., 9Z,12Z,15Z-C18:3 acid. α-Linolenic acid is 6Z,9Z,12Z-C18:3 acid and linoleic acid is 9Z,12Z-C18:2 acid (see TABLE 1).
TABLE 1 N o Fatty Acid Trivial Name Structure 1 9Z, 12Z, 15Z-C18:3 α-Linolenic Acid 2 6Z, 9Z, 12Z-C18:3 γ-Linolenic Acid 3 9Z, 12Z-C18:2 Linoleic Acid
[0005] Migration of double bonds (e.g., leading to conjugation) gives rise to many positional and geometric (i.e., cis-trans) isomers.
[0006] Conjugated double bonds means two or more double bonds which alternate with single bonds as in 1,3-butadiene. The hydrogen atoms are on the same side of the molecule in the case of cis-structure. The hydrogen atoms are on opposite sides of the molecule in the case of trans-structure.
[0007] Conjugated linoleic acid (CLA) is a general term used to name positional and geometric isomers of linoleic acid. Linoleic acid is a straight chain carboxylic acid having double bonds between the carbons 9 and 10, and between carbons 12 and 13. For example, one CLA positional isomer has double bonds between carbons 9 and 10 and carbons 11 and 12 (i.e., 9Z,11E-C18:2 acid); another has double bonds between carbons 10 and 11 and carbons 12 and 13 (i.e., 10E,12Z-C18:2 acid), each with several possible cis-and trans-isomers (see Table 2).
TABLE 2 N o Fatty Acid Trivial Name Structure 1 9Z, 11E-C18:2 Rumenic Acid 2 10E, 12Z-C18:2 none
[0008] The 9Z,11E-C18:2 isomer has been shown to be the first intermediate produced in the biohydrogenation process of linoleic acid by the anaerobic rumen bacterium Butyrvibrio fibrisolvens. This reaction is catalyzed by the enzyme Δ11 isomerase which converts the cis-12 double bond of linoleic acid into a trans-11 double bond (C. R. Kepler et al., 241, J. Biol. Chem. (1966) 1350). It has also been found that the normal intestinal flora of rats can also convert linoleic acid to the 9Z,11E-C18:2 acid isomer. The reaction does not, however, take place in animals lacking the required bacteria. Therefore, CLA is largely a product of microbial metabolism in the digestive tract of primarily ruminants, but to a lesser extent in other mammals and birds.
[0009] The free, naturally occurring conjugated linoleic acids (CLA) have been previously isolated from fried meats and described as anticarcinogens by Y. L Ha, N K. Grimm and M. W. Pariza (Carcinogenesis, Vol. 8, No. 12, pp. 1881-1887 (1987)). Since then, they have been found in some processed cheese products (Y. L. Ha, N. K. Grimm and M. W. Pariza, J. Agric. Food Chem., Vol. 37, No. 1, pp. 75-81 (1987)). Cook et al. (U.S. Pat. No. 5,554,646) disclose animal feeds containing CLA, or its non-toxic derivatives, e.g., such as sodium and potassium salts of CLA, as an additive in combination with conventional animal feeds or human foods. CLA makes for leaner animal mass.
[0010] The biological activity associated with CLAs is diverse and complex (Pariza et al., Prog. Lipid Research., Vol 40, pp. 283-298).
[0011] Anti-carcinogenic properties have been well documented, as well as stimulation of the immune system. Administration of CLA inhibits rat mammary tumorogenesis, as demonstrated by Ha et al., (Cancer Res., 52:2035-s (1992)). Ha et al., (Cancer Res., 50:1097 (1990)), reported similar results in a mouse forestomach neoplasia model. CLA has also been identified as a strong cytotoxic agent against target human melanoma, colorectal and breast cancer cells in vitro. A recent major review article confirms the conclusions drawn from individual studies (Ip, Am. J. Clin. Nutr. 66(6):1523s (1997)). In in vitro tests, CLAs were tested for their effectiveness against the growth of malignant human melanomas, colon and breast cancer cells. In the culture media, there was a significant reduction in the growth of cancer cells treated with CLAs by comparison with control cultures. The mechanism by which CLAs exert anticarcinogenic activity is unknown. In addition, CLAs have a strong antioxidative effect so that, for example, peroxidation of lipids can be inhibited (Atherosclerosis 108, 19-25 (1994)). U.S. Pat. 5,914,346 discloses the use of CLAs to enhance natural killer lymphocyte function. U.S. Pat. No. 5,430,066 describes the effect of CLAs in preventing weight loss and anorexia by immune system stimulation.
[0012] Although the mechanisms of CLA action are still obscure, there is evidence that some component(s) of the immune system may be involved, at least in vivo. U.S. Pat. No. 5,585,400 (Cook, et al.), discloses a method for attenuating allergic reactions in animals mediated by type I or IgE hypersensitivity, by administering a diet containing CLA. CLA in concentrations of about 0.1 to about 1.0 percent was also shown to be an effective adjuvant in preserving white blood cells. U.S. Pat. No. 5,674,901 (Cook, et al.), teaches that oral or parenteral administration of CLA in either free acid or salt form resulted in an elevation in CD-4 and CD-8 lymphocyte subpopulations associated with cell mediated immunity. Adverse effects arising from pretreatment with exogenous tumor necrosis factor could be alleviated indirectly by elevation or maintenance of levels of CD-4 and CD-8 cells in animals to which CLA was administered.
[0013] CLAs have also been found to exert a profound generalized effect on body composition, in particular, upon redirecting the partitioning of fat and lean tissue mass. U.S. Pat. Nos. 5,554,646 and 6,020,378 teach the use of CLAs for reducing body fat and increasing lean body mass. U.S. Pat. No. 5,814,663 teaches the use of CLAs to maintain an existing level of body fat or body weight in humans. U.S. Pat. No. 6,034,132 discloses the use of CLAs to reduce body weight and treat obesity in humans. CLAs are also disclosed in U.S. Pat. No. 5,804,210 to maintain or enhance bone mineral content. EP 0 579 901 B relates to the use of CLA for avoiding loss of weight or for reducing increases in weight or anorexia caused by immunostimulation in humans or animals. U.S. Pat. No. 5,430,066 (Cook, et al.), teaches the effect of CLA in preventing weight loss and anorexia by immune stimulation.
[0014] CLA has been found to be an in vitro antioxidant, and in cells, it protects membranes from oxidative attack. In relation to other important dietary antioxidants, it quenches singlet oxygen less effectively than β-carotene but more effectively than α-tocopherol. It appears to act as a chain terminating antioxidant by chain-propagating free radicals (U.S. Pat. No. 6,316,645).
[0015] Skin is subject to deterioration through dermatological disorders, environmental abuse (wind, air conditioning, central heating) or through the normal aging process (chronoaging) which may be accelerated by exposure of skin to sun (photoaging). In recent years the demand for cosmetic compositions and cosmetic methods for improving the appearance and condition of skin has grown enormously. WO 95/13806 teaches the use of a composition comprising zinc salts of 68% (unconjugated) linoleic acid and 10% conjugated isomers of linoleic acid for use in treating skin disorders.
[0016] Apart from potential therapeutic and pharmacological applications of CLA as set forth above, there has been much excitement regarding the use of CLA as a dietary supplement. CLA has been found to exert a profound generalized effect on body composition, in particular redirecting the partitioning of fat and lean tissue mass. U.S. Pat. No. 5,554,646 (Cook, et al.), teaches a method utilizing CLA as a dietary supplement in which pigs, mice, and humans were fed diets containing 0.5% CLA. In each species, a significant drop in fat content was observed with a concomitant increase in protein mass. It is interesting that in these animals, increasing the fatty acid content of the diet by the addition of CLA resulted in no increase in body weight, but was associated with a redistribution of fat and lean tissue mass within the body. Another dietary phenomenon of interest is the effect of CLA supplementation on feed conversion. U.S. Pat. No. 5,428,072 (Cook, et al.), discloses data showing that the incorporation of CLA into animal feed (birds and mammals) increased the efficiency of feed conversion leading to greater weight gain in the CLA supplemented birds and mammals. The potential beneficial effects of CLA supplementation for food animal growers is apparent.
[0017] Another important source of interest in CLA, and one which underscores its early commercial potential, is that it is naturally occurring in foods and feeds consumed by humans and animals alike. In particular, CLA is abundant in products from ruminants. For example, several studies have been conducted in which CLA has been surveyed in various dairy products. Aneja, et al., (J. Dairy Sci., 43: 231 [1990]) observed that processing of milk into yogurt resulted in a concentration of CLA. Shanta, et al. (Food Chem., 47: 257 [1993]) showed that a combined increase in processing temperature and addition of whey increased CLA concentration during preparation of processed cheese. In a separate study, Shanta, et al., (J. Food Sci., 60: 695 [1995]) reported that while processing and storage conditions did not appreciably reduce CLA concentrations, they did not observe any increases. In fact, several studies have indicated that seasonal or interanimal variation can account for as much as three fold differences in the CLA content of cows milk (Parodi, et al., J. Dairy Sci., 60: 1550 [1977]). Also, dietary factors have been implicated in CLA content variation (Chin, et al., J. Food Comp. Anal., 5: 185 [1992]). Because of this variation in CLA content in natural sources, ingestion of prescribed amounts of various foods will not guarantee that the individual or animal will receive the optimum doses to ensure achieving the desired nutritive effect.
[0018] Economical conjugated fatty acid production in commercial quantities for use in domestic food animal feeds is a desirable objective in light of the nutritional benefits realized on a laboratory scale. Preferably, the conjugated fatty acid is produced directly from a source of raw vegetable oil and not from expensive purified linoleic acid. Further, the process must avoid cost generating superfluous steps, and yet result in a safe and wholesome product palatable to animals.
[0019] Useful methodologies for the preparation of conjugated linoleic acid (CLA) have been recently reviewed by Adlof (In:Yurawecz et al. (Ed), Advances in Conjugated Linoleic Acid Research, volume 1, AOCS Press, Champaign, Ill., pp 21-38 [1999]).
[0020] The usual methodology for conjugation of polyunsaturated fatty acids is alkali-catalyzed isomerization. This reaction may be performed using different bases such as hydroxides or alkoxides in solution in appropriate alcoholic reagents. This reaction was developed in the 1950's for the spectrophotometric estimation of polyunsaturated fatty acids in fats and oils [AOCS official method Cd 7-58; JAOCS 30:352 (1953)].
[0021] In alkali isomerization the fatty acids are exposed to heat, pressure and a metal hydroxide or oxide in nonaqueous or aqueous environments, resulting in the formation of conjugated isomers. Other methods have been described which utilize metal catalysts, but which are not as efficient for the operation of conjugated double bonds. It was found that isomerization could be more rapidly achieved in the presence of higher molecular weight solvents. Kass, et al., (J. Am. Chem. Soc., 61: 4829 (1939)) and U.S. Pat. No. 2,487,890 teach that the replacement of ethanol with ethylene glycol resulted in an increase in conjugation in less time. U.S. Pat. No. 2,350,583 and British Patent 558,881 teach conjugation by reacting fatty acid soaps of an oil with an excess of aqueous alkali at 200-230° C. and increased pressure.
[0022] Dehydration of methyl ricinoleate (methyl 12-hydroxy-cis-9-octadecenoate) (Gunstone and Said, Chem. Phys. Lipids 7, 121 [1971]; Berdeaux et al., JAOCS 74, 1011 [1997]) yields the 9Z,11E-C18:2 isomer as a major product. U.S. Pat. No. 5,898,074 teaches a synthetic process for producing this fatty acid at room temperature in high yield. The tosylate or the mesylate of the methyl ester of ricinoleic acid is formed with tosyl chloride or mesyl chloride in a pyridine solvent or in acetonitrile and triethyl amine. The obtained tosylate or mesylate was reacted with diazabicycloundecene in a polar, non-hydroxylic solvent such as acetonitrile to form the preferred isomer 9Z,11E-18:2 methyl ester in high yield. U.S. Pat. No. 6,160,141 discloses a synthetic process for producing conjugated eicosanoid fatty acid from methyl lesquerolate (methyl 14-hydroxy-cis-11-octadecenoate) at room temperature in high yield using the same principle.
[0023] Among the processes known to effect isomerization, without utilizing an aqueous alkali system, is a nickel-carbon catalytic method, as described by Radlove, et al., Ind. Eng. Chem.38: 997 (1946). A variation of this method utilizes platinum or palladium-carbon as catalysts. Conjugated acids may also be obtained from a-hydroxy allylic unsaturated fatty adds using acid catalyzed reduction (Yurawecz et al., JAOCS 70, 1093 [1993]) as well as by the partial hydrogenation of conjugated acetylenic acid such as santalbic (11E-octadec-9-ynoic) acid using Lindlar's catalyst but the methods are limited by natural sources of such fatty acids. Another approach using strong organic bases such as butyllithium has been applied to both the conjugation of linoleic acid and the partial and full conjugation of alpha-linolenic acid (U.S. Pat. No. 6,316,645).
[0024] Natural fully conjugated linolenic acids have been found at high content levels in some seed oils (Hopkins, In:Gunstone, F. D. (Ed), Topics in Lipid Chemistry, volume 3, ELEK Science, London, pp 37-87 [1972]). For example, Takagi and Itabashi (Lipids 16, 546 [1981]) reported calendic acid (8E,10E,12Z-C18:3 acid, 62.2%) in pot marigold seed oil, punicic acid (9Z,11E,13Z-C18:3 acid, 83.0%) in pomegranate seed oil; α-eleostearic acid (9Z,11E,13E-C18:3 acid) in tung (67.7%) and bitter gourd (56.2%) seed oils; and catalpic acid (9E,11E,13Z-C18:3 acid, 42.3%) in catalpa seed oil, respectively.
[0025] An octadecatrienoic acid isomer whose structure has been tentatively defined as 9Z,11E,15Z-C18:3 acid, is believed to be the first intermediate in the biohydrogenation process of α-linolenic acid by the anaerobic rumen bacterium Butyrvibrio fibrisolvens (C. R. Kepler and S. B. Tove 242 J. Biol. Chem. (1967) 5686).
[0026] There thus remains a need to develop a method for the preparation and purification of new conjugated linolenic acids.
[0027] The present invention seeks to meet these and other needs.
[0028] The present invention refers to a number of documents, the content of which is herein incorporated by reference in their entirety.
SUMMARY OF THE INVENTION
[0029] The present invention relates to a method for the preparation and purification of fatty acids which are homologues of conjugated linoleic acids, from natural and/or synthetic materials richin alpha or gamma linolenic acids or both. In a preferred embodiment, the method transforms approximately over two thirds of alpha linolenic acid (9Z,12Z,15Z-C18:3 acid), from a natural source such as linseed oil, into 9Z,11E,15Z and 9Z,13E,15Z C18:3 acids, producing a mixture comprising approximately 30% of the conjugated linolenic acids. In a further embodiment, enrichment up to and over 40% is readily performed with urea crystallization. Moreover, the product is obtained in over 90% purity by simple preparative liquid chromatography. The products obtained include free fatty acids, and derivatives thereof, including, but not limited to esters, amides, salts as well as fatty alcohols The method of the present invention produces the above mentioned conjugated trienoic acid with a high selectivity, in a short time period and under relatively mild conditions
[0030] The present invention further relates to a method for preparing conjugated linolenic acids comprising the steps of:
(a) blending a or a mixture of vegetable oils and/or fats including various concentrations of alpha or gamma and or both linolenic acids with a base to produce a reaction mixture; (b) recovering said conjugated linolenic acids from the reaction mixture, and (c) subjecting the reaction mixture to urea complexation or liquid chromatography.
[0034] Further scope and applicability will become apparent from the detailed description given hereinafter. It should be understood however, that this detailed descripton, while indicating preferred embodiments of the invention, is given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art.
BRIEF DESCRIPTION OF FIGURES
[0035] FIG. 1 shows mass spectra of products resulting from the isomerization process of alpha-linolenic acid (9Z,12Z,15Z-C18:3 acid), as 4,4-dimethyloxazoline derivatives: A, 9Z,11E,15Z and 9Z,13E,15Z-C18:3; B, 9,11,13-C18:3, C, 10E,12Z,14E-C18:3 and D, 11,13-CCLA (9-(Spropylcyclohexa-2,4-dienyl)-nonanoic acid);
[0036] FIG. 2 shows the mass sprectrum of the MTAD adducts of cis-9, trans-11, cis-5 18:3 (A) and cis-9, trans-13, cis-15 18:3 (B) acid, methyl esters;
[0037] FIG. 3 shows the thermal mechanism leading to the formation of 11,13-CCLA [9-(6propyl-cyclohexa-2,4-dienyl)-nonanoic acid ( FIG. 1 -D)] from 10E,1Z,14E-C18:3 acid;
[0038] FIG. 4 illustrates gas liquid chromatograms of fatty acid methyl esters obtained after methylation of linseed oil (A), conjugated linseed oil (B), liquid phase from urea crystallization (C), reversed-phase liquid chromatography fraction containing about 97% of a mixture of 9Z,11E,15Z and 9Z,13E,15Z-C18:3 acids (D), argentation liquid chromatography fraction containing about 99+% of a mixture of 9Z,11E,15Z and 9Z,13E,15Z-C18:3 acids (E);
[0039] FIG. 5 illustrates the gas liquid chromatogram of the fatty acid methyl esters obtained after methylation of partially conjugated evening primrose oil.
DETAILED DESCRIPTION OF THE INVENTION
[0040] The oils and fats, alone or as mixtures, containing alpha-linolenic acid may include but are not limited to amebia, basil, candelnut, flax (linseed), linola, gold of pleasure, hemp, mustard, perilla, soybean, canola, walnut, chia, crambe, echium, hop, kiwi, pumpkin, black currant and purslane seed oils, or any other oil, wax, ester or amide that is rich in linolenic acid.
[0041] The oils and fats, alone or as mixtures, containing gamma-linolenic acid may include but are not limited to borage, evening primrose and black currant seed oils, or any other oil, wax, ester or amide that is rich in linolenic add.
[0042] The disclosed method converts double bonds of α- and γ-linolenic acid isomers into partly and/or fully conjugated systems as well as into cyclic fatty acid isomers. The process, which can be performed both in batch and continuous modes, involves blending one or a mixture of vegetable oils with various concentrations of alpha or gamma linolenic acids or both or partial glycerides of such oils, or partially purified or concentrated isomers with about 0.5 to about 10 moles of base such as sodium hydroxide, sodium alkoxylate, sodium metal, potassium hydroxide, potassium alkoxylate, potassium metal, and strong base resins. The reaction proceeds at temperatures from about 20° C. to about 280° C. in a solvent, selected from commercial polyols such as propylene glycol, glycerol and ethylene glycol, for periods ranging from about 30 seconds to about 18 hours, depending on the base and/or the temperature and/or solvent, and/or substrate and/or a desired expected conversion rate. After cooling, if required, to about 20-80° C., acid is added to the reaction mixture to neutralize the soaps and/or remaining base in the reactor. It is preferred to bring the pH of the contents of the reactor to a value of about 4 or less through the addition of either a mineral or organic acid. Acids that may be used include, but are not limited to, hydrochloric acid, sulfuric acid, phosphoric acid and citric acid. The solvent phase (polyol+water) is withdrawn and the remaining fatty acid rich phase can be washed with water and/or saline solutions of variable concentrations such as sodium chloride (5% w/w) to remove traces of acids used for acidification of the reaction mixture. Remaining water can be removed by usual means (ie. centrifugation, vacuum, distillation or drying agents). As described in Example 1, the concentration of 9Z,11E,15Z and 9Z,13E,15Z-C18:3 acid in the product is approximately 33/. This product, as such or converted into derivatives, can be used in nutrition, cosmetic, nutraceutical, biological and/or animal feed applications.
[0043] The isomer composition of the formed fatty acid was determined using gas-liquid chromatography coupled with a mass-spectrometer (GC-MS) of their corresponding 4,4-dimethyloxazoline (DMOX) derivatives. The use of derivatives is a necessary step prior to the structural determination of fatty acids by GC-MS because the mass spectra of fatty acid methyl esters, the usual derivatives for gas-liquid chromatography analysis, are devoid of sufficient information for the identification of structural isomers. This is mainly due to the high sensitivity of the carboxyl group to fragmentation and to double bond migration (Christie, W. W., Gas Chromatography-Mass Spectrometry Methods for Structural Analysis of Fatty Acids, Lipids 33:343-353 (1998)). However, stabilization of the carboxyl group by the formation of a derivative containing a nitrogen atom results in mass spectra that allows for the structural determination of most fatty acids. Indeed, these fatty acid derivatives provide diagnostic fragments that allow accurate structure determination. The derivatives were submitted to GC-MS using a Hewlett Packard 5890 Series II plus gas chromatograph attached to an Agilent model 5973N MS Engine. The latter was used in the electron impact mode at 70 eV with a source temperature of 230° C. For the DMOX derivatives, an open tubular capillary column coated with BPX-70 (60 m.times.0.25 mm, 0.25 μm film; SGE, Melbourne, Australia) was used. After holding the temperature at 60° C. for 1 minute, the oven temperature was increased by temperature-programming at 20° C./minute to 170° C. where it was held for 30 minutes, then at 5° C./minute to 210° C. where it was held for 30 minutes. Helium was the carrier gas at a constant flow-rate of 1 mL/minute, maintained by electronic pressure control.
[0044] The mass spectrum of the conjugated products of 9Z,12Z,15Z-C18:3 acid, obtained by conjugation of linseed oil, are presented in FIG. 1 .
[0045] The structural formula and mass spectrum of the DMOX derivatives of the 9Z,11E,15Z-C18:3 acid are illustrated in FIG. 1A . DMOX has a molecular ion at m/z=331, confirming the octadecatrienoic acid structure. The ion at m/z=262 confirms the location of the 11,15-double bond system (by extrapolation from the known 5,9-isomer (Berdeaux and Wolff, J. Am. Oil Chem. Soc., 73: 1323-1326 (1996)), similarly, the molecular ion at m/z=236 confirms the location of the 9,13-double bond system, and gaps of 12 a.m.u. between m/z=208 and 196, and 288 and 276 verify the location of double bonds in positions 9 and 15, respectively. Mass spectrometry does not however confirm the geometry of the double bonds, but they have been determined according to Nichols et al. (J. Am. Chem. Soc, 73:247-252 (1951)) based on the Ingold theory on the prototropic shift mechanism (Ingold, J. Chem. Soc, 1477 (1926)).
[0046] The structural formula and mass spectrum of the DMOX derivatives of the 9,11,13-C18:3 acid are illustrated in FIG. 1B . DMOX has a molecular ion at m/z=331, confirming the octadecatrienoic acid structure. Gaps of 12 a.m.u. between m/z=208 and 196, and 222 and 234, and 248 and 260 verify the location of the double bonds in positions 9, 11 and 13, respectively. Four different minor isomers of 9,11,13-C18:3 are present in the reaction products. The most abundant is the 9Z,11Z,13E-C18:3 acid isomer which is known as a-eleostearic add.
[0047] The mass spectra of the MTAD adducts of cis-9,trans-11 ,cis-15 18:3 (A) and cis-9,trans-13,cis-15 18:3 (B) acid methyl esters and presented in FIG. 2 .
[0048] The structural formula and mass spectrum of the DMOX derivatives of the 10E,12Z,14E-C18:3 acid are illustrated in FIG. 1C . DMOX has a molecular ion at m/z=331, confirming the octadecatrienoic acid structure. Gaps of 12 a.m.u. between m/z=210 and 222, and 236 and 248, and 262 and 274 verify the location of the double bonds in positions 10, 12 and 14, respectively. The geometry of the double bonds, has been determined according to Nichols et al. (J. Am. Chem. Soc, 73:247-252 (1951)) based on the Ingold theory on the prototropic shift mechanism (Ingold, J. Chem. Soc, 1477 (1926)). The 10E,12Z,14E-C18:3 acid isomer is prone to cyclization, thus forming the cyclohexadienyl compound (9-(6-propyl-cyclohexa-2,4dienyl)-nonanoic acid)) by an electrocyclization process presented in FIG. 3 .
[0049] The structural formula and mass spectrum of the DMOX derivatives of the 11,13-CCLA (9-(6-propyl-cyclohexa-2,4-dienyl)-nonanoic acid) are illustrated in FIG. 1 D . DMOX has a molecular ion at m/z=330−1, confirming the occurrence of a highly stabilized conjugated ion fragment (radical in carbon 10 or 15, stabilized by resonance effect). A distinctive ion at m/z=288 is characteristic of alpha cleavage occurring in cyclic fatty acids (Sébédio et al. J. Am. Oil Chem. Soc., 64: 1324-1333 (1987)). The gap of 78 atomic mass units (a.m.u.) between m/z=288 and 210 is that expected for the cyclohexadienyl group having a conjugated double bond system in positions 11 and 13.
[0050] The reaction progress was determined by gas-liquid chromatography under appropriate condition as presented in Example 1.
[0051] An increase in the concentration of, for example the 9Z,11E,15Z and 9Z,13E,15Z-C18:3 acids, can be achieved using different methods, alone or in combination. One method makes use of urea complexation. A urea solution is prepared at a temperature ranging from about 20 to 90° C. in different solvents or mixtures thereof, selected from water, and/or alcohols. Complexation is performed at the same temperature by addition of the product in a molar ratio of about 0.5 to 8, and cooling to a temperature range of about 30° C. to about −30° C., as required. A mixture of the above mentioned 9Z,11E,15Z and 9Z,13E,15Z-C18:3 acids is isolated in higher concentration following treatment of the liquid phase, obtained after separation from the solid phase using conventional means such as filtration or centrifugation. Decomplexation is then carried out by the addition of either a diluted organic or mineral acid. Acids that may be used include, but are not limited to, hydrochloric acid, sulfuric acid, phosphoric acid and citric acid. The product is obtained by decantation or liquid-liquid extraction with an organic solvent such as but not limited to hexane, heptane, petroleum ether and ligroin. If required, the organic solvent is eliminated (i.e. evaporation or distillation). A preferred description of the present embodiment is described in Example 2.
[0052] Another method for raising the level of, for example the 9Z,11E,15Z and 9Z,13E,15Z -C18:3 acids, either as free acids or derivatives (i.e. methyl, ethyl, isopropyl, butyl, phenyl) comprises the use of liquid chromatography using various convenient stationary phases. One particular chromatographic method is reversed phase liquid chromatography (i.e. ODS) for which eluents may include but are not limited to water, acetonitrile, acetone, methanol, tetrahydrofuran, methyltertbutyl ether, and combinations thereof. A detailed description of this method is provided in Example 3.
[0053] Argentation liquid chromatography may be used to isolate specific isomers from a complex mixture of fatty acid esters or free fatty acids. A detailed description of this methodology applied to a mixture of 9Z,11E,15Z and 9Z,13E,15Z-C18:3 acid isomers is described in Example 4.
[0054] Still another method for raising the concentration level of, for example, a mixture of 9Z,11E,15Z and 9Z,13E,15Z-C18:3 acids, either as free acids or derivatives (i.e. methyl, ethyl, isopropyl, butyl, phenyl) is crystallization, either in a solvent such as, but not limited to, acetone, methanol, pentane, or in mixtures therefor, or in the absence of a solvent (i.e. dry fractionation). A detailed cooling program is required in order to obtain a more concentrated product. One particular case is that of further crystallization of urea complexes of fatty acids.
[0000] Experimental
[0055] In the experimental disclosure which follows, the following abbreviations apply: kg (kilograms); g (grams); mg (milligrams); ° C. (degrees centigrade); L (liters); mL (milliliters); μL (microliters); m (meters); cm (centimeters); mm (millimeters), μm (micrometers); NaOH (sodium hydroxide), H 2 SO 4 (sulfuric acid), NaCl (sodium chloride); 11,13-CCLA (9-(6-propyl-cyclohexa-2,4-dienyl)-nonanoic acid), AgNO 3 (silver nitrate).
EXEMPLE 1
Preparation of a Mixture Containing High Amounts of 9Z,11E,15Z and 9Z,13E,15Z-C18:3 Acids by Conjugation of Linseed Oil
[0056] To commercial propylene glycol (46.48 kg) were added NaOH (1.94 kg) at room temperature. The resulting mixture was heated at 160° C. for 20 minutes into a 200 L stainless steal reactor under a nitrogen atmosphere and with vigorous agitation. Commercial raw linseed oil (4.19 kg) was added under a nitrogen atmosphere. The mixture was heated at 160° C. for 2 hours under a nitrogen atmosphere and with vigorous agitation. After cooling to 80° C., the reaction mixture was directly acidified with an aqueous solution of H 2 SO 4 (0.06% w/w, 47.5 kg). After standing for about 10 minutes, the top layer was washed with a NaCl aqueous solution (5% w/w, 47.25 kg). The top layer was removed, dried and stored at −80° C. under nitrogen.
[0057] The fatty acid composition of the resulting product was determined using high resolution gas-chromatography following methylation of a sample (20 mg) using boron trifluoride (Metcalfe et al.,). The analytical equipment consisted of an Agilent Technologies GLC 6890 with auto sampler. The column was a highly polar open tubular capillary type. The following program settings were used (TABLE 3)
TABLE 3 Inj ction Split mode 1:50 at 250° C. Det ction Flame Ionization Detector at 250° C. Carrier Helium at 249.5 KPa at 170° C. Oven 60° C. for 1 minute then 20° C./minute to 170° C. and Program 170° C. throughout for 30 minutes, then 5° C./minute 210° C. throughout for 5 minutes Column BPX-70 capillary column, 60 m × 0.25 mm i.d., 0.25 μm film thickness
[0058] The obtained chromatogram is shown in FIG. 4B . The quantitative conversion of alpha-linolenic acid was confirmed and the mixture comprises approximately 33% of 9Z,11E,15Z and 9Z,13E,15Z-C18:3. The fatty acid composition of the mixture is given in Table 4.
TABLE 4 Fatty Acid % Before Reaction % After Reaction Palmitic 5.40 5.07 Stearic 4.13 3.20 Oleic 19.77 19.27 11Z-C18:1 0.69 0.65 Linoleic 16.47 7.16 alpha-Linolenic 53.54 0.87 9Z,11E-C18:2 0.00 4.89 10E,12Z-C18:2 0.00 4.79 11,13-CCLA 0.00 8.73 9Z,11E,15Z-C18:3 0.00 32.98 9,11,13-C18:3 1 0.00 3.73 10E,12Z,14E-C18:3 0.00 6.06 10,12,14-C18:3 2 0.00 1.41 1 stereochemistry of the double bonds not identified 2 other stereo isomers of 10,12,14-C18:3 Acid
EXEMPLE 2
Preparation of Mixtures Containing High Amounts of a Mixture of 9Z,11E,15Z and 9Z,13E,15Z-C18:3 Acid by Conjugation of Linseed Oil and Consecutive Urea Crystallization
[0059] The top layer (3.26 kg) obtained in Example 1 was removed and transferred into a 20 L reactor containing a solution of urea (3.26 kg) in aqueous ethanol (95%, v/v, 13.20 kg), prepared at 60° C. under a nitrogen atmosphere. The free fatty acids were homogenized and the obtained mixture was cooled at 4° C. for 12 h. The liquid phase (17.77 kg) was removed from the solid phase (3.18 kg) by centrifugation and transferred into a 100 L, stainless steal, sight glasses reactor. An aqueous solution of H 2 SO 4 (0.1%, w/w, 49.12 kg) was added to the mixture and the solution was vigorously shaken for 1 minute under a nitrogen atmosphere. After standing for 10 minutes, the top layer was washed with an aqueous a NaCl solution (5% w/w, 47.25 kg). The top layer was removed, dried and stored at −80° C. under nitrogen.
[0060] The solid phase (3.18 kg) was dissolved in a solution of H 2 SO 4 (0.1%, w/w, 49.12 kg) at 70° C. and transferred into a 107 L, stainless steal, sight glasses reactor and the solution was vigorously shaken for 1 minute under a nitrogen atmosphere. After standing for 10 minutes, the top layer was washed in the same apparatus with an aqueous NaCl solution (5% w/w, 47.25 kg). The top layer was removed, dried and stored at −80° C. under nitrogen.
[0061] The fatty acid composition of the resulting products was determined using high resolution gas-chromatography following methylation of samples (20 mg) using boron trifluoride (Metcalfe et al.,). The analytical conditions used were the same as presented in Example 1.
[0062] The chromatogram obtained is shown in FIG. 4C . The fatty acid composition of the mixture is illustrated in Table 5.
TABLE 5 % Before % in Liquid % in Solid Fatty Acid Crystallization Phase Phas Palmitic 5.07 0.58 15.41 Stearic 3.20 0.04 12.17 Oleic 19.27 17.19 27.88 11Z-C18:1 0.65 0.66 0.84 Linoleic 7.16 8.50 2.60 alpha-Linolenic 0.87 0.79 0.17 9Z,11E-C18:2 4.89 5.86 4.17 10E,12Z-C18:2 4.79 6.21 2.59 11,13-CCLA 8.73 10.61 1.42 9Z,11E,15Z and 9Z,13E,15Z- 32.98 40.74 10.88 C18:3 9,11,13-C18:3 1 3.73 3.54 3.17 10E,12Z,14E-C18:3 6.06 0.73 13.78 10,12,14-C18:3 2 1.41 1.26 1.72 1 stereochemistry of the double bonds not identified 2 other stereo isomers of 10,12,14-C18:3 Acid
EXEMPLE 3
Preparation and Purification of a Mixture of 9Z,11E,15Z and 9Z,13E,15Z-C18:3 Acids by Reverse Phase Liquid Chromatography
[0063] The products obtained in Examples 1 and 2 containing a high level of 9Z,11E,15Z and 9Z,13E,15Z-C18:3 were submitted to a preparative high performance liquid chromatograph fitted with a preparative ODS (octadecylsilyl) column (25 cm×6.5 cm i.d.). The mobile phase was methanol and water (90:10, v/v, 400 mL/minute). The sample (10 g) was injected at atmospheric pressure and the separation was achieved in 60 minutes. The collected fractions were analyzed by gas-liquid chromatography as presented in Example 1, and a typical gas-chromatogram is presented in FIG. 4D . The desired compounds eluted in the first partition (partition number=12) allowing for a purification of about 95%.
EXEMPLE 4
Preparation and Purification of 9Z,11E,15Z and 9Z,13E,15Z-C18:3 Acids by Argentation Liquid Chromatography
[0064] The fatty acid methyl esters prepared from the products obtained in Examples 1 and 2, containing a high level of a mixture of 9Z,11E,15Z and 9Z,13E,15Z-C18:3, were separated using argentation thin layer chromatography. Silica-gel plates were prepared by immersion in a 5% acetonitrile solution of AgNO 3 as described by Destaillats et al. (Lipids 35:1027-1032, (2000)). The developing solvent was a n-hexane/diethyl ether (90:10, v/v) mixture. At the end of the chromatographic runs, the plates were briefly air-dried, lightly sprayed with a solution of 2′,7′-dichlorofluorescein, and viewed under ultraviolet light (234 nm). The band at R f =0.52 was scraped off and eluted several times with diethyl ether. Complete evaporation of the combined extracts was achieved with a light stream of dry nitrogen. The residues were dissolved in an appropriate volume of n-hexane and analysed by gas-liquid chromatography (purity superior to 98%) as presented in Example 1.
EXEMPLE 5
Preparation of Mixture Containing 6Z,8E,12Z,6Z,10E,12Z- and 6Z,9Z,12Z-C18:3 Acids by Partial Conjugation of Borage Oil
[0065] NaOH (4.30 g) was added to commercial propylene glycol (96 g) at room temperature. The resulting mixture was heated at 160° C. for 20 minutes under a nitrogen atmosphere and with vigorous agitation. Commercial borage oil (9.35 g) was then added under a nitrogen atmosphere. The mixture was heated at 160° C. for 1 hour under nitrogen and with vigorous agitation. After cooling to 80° C., the reaction mixture was directly acidified with an aqueous solution of H 2 SO 4 . After standing for 10 minutes, the top layer was washed with a 5% aqueous NaCl solution (w/w, 47.25 kg), removed, dried and stored at −80° C. under nitrogen.
[0066] The fatty acid composition of the resulting products was determined using high resolution gas-chromatography after methylation of samples (20 mg) using boron trifluoride (Metcalfe et al.,). The analytical conditions used were the same as presented in Example 1.
[0067] The obtained chromatogram is shown in FIG. 5 . The fatty acid composition of the mixture is given in Table 6.
TABLE 6 Fatty Acid % Before Reaction % After Reaction Palmitic 10.34 9.55 Stearic 3.36 2.38 Oleic 15.57 13.88 11Z-C18:1 0.57 0.52 Linoleic 39.96 30.11 ?-Linolenic 22.92 5.32 7,11-CCLA 0.00 1.25 9Z,11E-C18:2 0.00 6.66 10E,12Z-C18:2 0.00 6.46 9Z-C20:1 3.69 2.60 6Z,8E,12Z and 6Z,10E,12Z- 0.00 14.50 C18:3 9Z-C22:1 2.05 1.22 7E,9Z,11E-C18:3 0.00 1.89
[0068] Although the present invention has been described herein above by way of preferred embodiment thereof, it can be modified without departing from the spirit and nature of the subject invention as defined in the appended claims. | A method for the preparation and purification of conjugated linolenic acids is described. The method comprises blending a mixture of vegetable oils and or fats including various concentrations of alpha or gamma and or both linolenic acids with a base. The method transforms approximately over two thirds of α-linolenic acid (9Z,12Z,15Z-octadecatrienoic acid) into 9Z,11E,15Z-octadecatrienoic acid and 9Z,13E,15Z-octadecatrienoic acid. The method also transforms gamma-linolenic acid (6Z,9Z,12Z-octadecatrienoic acid) into 6Z,8E,15Z-octadeccatrienoic acid and 6Z,10E,12Z-octadecatrienoic acid. In all cases, geometrical isomers and fully conjugated isomers are also produced. | 2 |
BACKGROUND
[0001] Clinical trials of pharmaceutical/medical products are lengthy and expensive due in part to delays resulting from inefficiencies in communications between participants in the trial. For certain products, each day by which the introduction to the market is delayed may cost the pharmaceutical company millions of dollars.
[0002] In a typical case, review and transfer of medical data, such as radiology data (“R/D”) including radiology image data, and related reports as currently handled among clinical trial participants unduly delay the clinical trial process. Typically, participants may transmit the medical data, including image data and related reports, by courier, mail or other document delivery services. Each such communication may delay the progress of the clinical trials by one or more days.
[0003] For example, in the case of radiology images, a radiologist reviews the radiology data and generates a radiologist report. The report is forwarded to a physician for the patient who reviews the radiologist report and makes his own report. The patient physician then forwards both reports along with the radiology data to a monitoring facility for the clinical trial and/or directly to a clinical trial administrator group. The reports along with the corresponding radiology data are reviewed and processed at the respective facilities in accordance with clinical trial protocols and standards.
SUMMARY OF THE INVENTION
[0004] The present invention relates to a method and system for conducting a clinical trial. Medical data is obtained from a patient participating in the clinical trial. Then, the medical data and at least one identifier are transmitted, via a communications network, for storage at a remote server. The at least one identifier links the medical data to a record of the patient. Access to at least portions of the medical data is provided, via the communications network, to trial participants based on predefined clinical trial procedures. The remote server tracks accessing of the medical data by the trial participants and generation by the trial participants of work product responsive to the medical data.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 shows an exemplary embodiment of a system of conducting a clinical trial study according to the present invention.
[0006] FIG. 2 shows an exemplary embodiment of a method for conducting a clinical trial according to the present invention.
[0007] FIG. 3 shows an exemplary embodiment of a medical facility medical data record according to the present invention.
[0008] FIG. 4 a shows an exemplary embodiment of a clinical trial medical data record according to the present invention.
[0009] FIG. 4 b shows an exemplary embodiment of an updated clinical trial medical data record according to the present invention.
[0010] FIG. 5 shows an exemplary embodiment of a clinical trial protocol according to the present invention.
DETAILED DESCRIPTION
[0011] The present invention may be further understood with reference to the following description of preferred exemplary embodiments and the related appended drawings. It should be understood that, although the preferred embodiment of the present invention will be described with reference to conducting clinical trials using radiology image data, the present invention may be implemented on a wide range of medical data including, for example, photographic image data, optical projection image data, image data of DNA chips, blood test report, etc., and the term “medical data” will be used through out this description to generically refer to all such types of data.
[0012] FIG. 1 shows an exemplary embodiment according to the present invention of a system 1 for conducting a clinical trial study. As it will be explained below in greater details, the system 1 utilizes efficient distribution and tracking techniques to minimize delays generally associated with conducting clinical trials. The system 1 may include one or more participating medical facilities 12 where patients 10 are examined. The medical facility 12 may be, for example, a hospital, a medical clinic, a physician's private office, etc. Each medical facility 12 may include one or more sources (e.g., medical equipment, medical personal) for collecting the patient's 10 medical data 204 . For example, the medical facility 12 may have a radiology imaging device 9 obtaining imaging data of at least one a portion of a patient's body. After the patient 10 is examined at the medical facility 12 , the medical data 204 is collected and stored in a digital format as a Medical Facility Medical Data Record (“MFMDR”) 200 , as shown in FIG. 3 and further described below. The MFMDR 200 is then transmitted to a remote facility 50 via, for example, a communications network 20 (e.g., the Internet, a Wide Area Network).
[0013] The system 1 may also include a physician 8 , a medical evaluator 22 , a monitoring facility 14 , and a clinical trial administration group (“CTAG”) 16 . The physician 8 may be responsible for examining the patient 10 , diagnosing and prescribing treatments. The medical evaluation 22 reviews and interprets the medical data 204 . In this exemplary embodiment, the radiological data would preferably be interpreted by a radiologist. The medical evaluator 22 may remote access the medical data 204 and then remotely submit the report.
[0014] The monitoring facility 14 may include a governmental agency like the U.S. Food and Drug Administration or other interested parties or sponsoring organizations. Alternatively, the monitoring facility 14 may include a clearinghouse that conducts and maintains the clinical trial study (e.g., for conducting day-to-day operations) which is initially defined by the CTAG 16 . For example, the CTAG 16 may set up parameters, timelines and deadlines that the clinical trial study should operate in accordance with and which are monitored by the monitoring facility 14 . Alternatively, the CTAG 16 may conduct the clinical trial study itself. However, as understood by those skilled in the art, the monitoring facility 14 may conduct the entire study and provide periodic reports to the CTAG 16 .
[0015] The CTAG 16 may, for example, include a pharmaceutical company, a medical device company, and/or a research group/organization. In one embodiment mentioned above, the CTAG 16 may conduct the clinical trial study itself. In an alternative embodiment as mentioned above, the CTAG 16 may develop the clinical trial study, which will be implemented and monitored by the monitoring facility 14 . The present invention allows for the CTAG 16 to more closely track the progress of the clinical trial study.
[0016] The remote facility 50 may, for example, include one or more servers 24 connected to one or more databases 26 where medical data 204 is stored. The remote facility 50 serves as a central facility where the medical data 204 from all participating patients 10 is stored and processed. The remote server 24 also provides participants of the trial study with an access to the medical data 204 . The remote server 24 may, for example, notify participants of arrival of new medical data 204 and track the progress of the clinical trial study.
[0017] FIG. 2 shows an exemplary embodiment of a method of conducting a clinical trial study. In the step 102 , the medical data 204 is collected at a medical facility 12 to generate the MFMDR 200 . Examinations to collect the medical data 204 may, for example, be performed by medical devices and/or medical facility personnel of the medical facility 12 . Such devices may, for example, include Computerized Tomography scan, Magnetic Resonance Imaging, Positron Emission Technology, X-Rays, Vascular Interventional and Angiogram/Angiography procedures, ultrasound imaging, radiographs, optical imaging, pathological imaging, molecular imaging, medical genetic imaging and DNA imaging. Subsequent to the examination, the MFMDR 200 for the examined patient 10 is generated.
[0018] An exemplary embodiment of the MFMDR 200 is illustrated in FIG. 3 , which, for example, may include, patient identification and personal information 202 (e.g., patient's name, address, social security number, date of birth, medical history, etc.), the medical data 204 , a medical data type 206 (e.g., the medical data 204 includes CAT scan, etc.), examination date 208 (e.g., the medical data 204 was collected on May 1, 2004 at 2 p.m.), and a medical facility identifier 210 (e.g., the medical data 204 was collected by the medical facility 12 ). The medical data 204 may include a plurality of medical related such radiological data, pathology data, etc.
[0019] In step 104 , the medical facility 12 determines if the patient 10 participates in any clinical trial studies. The medical facility 12 checks the patient identification information 202 against its internal database which stores a list of patients enrolled in the clinical trial studies. If the patient 10 does not participate in any clinical trials, the MFMDR 200 is stored at the medical facility 12 and no further steps need to be taken. However, if the patient 10 does participate in one or more clinical trials, the MFMDR 200 is utilized to generate a Clinical Trial Medical Data Record (“CTMDR”) 212 for the patient 10 (step 106 ).
[0020] An exemplary embodiment of the CTMDR 212 generated by the medical facility 12 is shown in FIG. 4 a . The CTMDR 212 includes an unique patient identification 214 , the medical data 204 , the medical data type 206 , the examination date 208 , the medical facility identifier 210 and a clinical trial study identifier 216 . During this process, the personal information 202 (e.g., name, address, social security number) of the patient 10 is at least partially removed and replaced with the unique patient identification 214 . The unique patient identifier 214 , for example, may be randomly generated by the CTAG 16 . The unique identifier 214 provides anonymity during the transfer the CTMDR 212 , preserves the patient's privacy and complies with government privacy regulations, such as, for example, the Health Insurance Portability and Accountability Act of 1996 (HIPAA).
[0021] The HIPAA imposes national standards for electronic health care transactions and national identifiers for providers, health plans, and employers. The HIPAA also mandates regulations for the security and privacy of health data. The present invention provides a system compatible with privacy requirements for handling the widespread use of electronic data interchange in health care.
[0022] In step 108 , the CTMDR 212 is then forwarded to the remote server 24 via the communications network 20 where it is stored in the database 26 and accessible by authorized participants of the clinical study such the physician 8 , the medical evaluators 22 , etc. In step 110 , the CTAG 16 is notified that the CTMDR 212 is transmitted to and received by the remote server 24 . As would be understood by those skilled in the art, notification to the CTAG 16 may be provided by a transmittal notification from the medical facility 12 or a receipt notification from the remote server 24 .
[0023] Upon the notification that the CTMDR 212 has been received by the remote server 24 , the CTAG 16 and/or the remote server 24 may perform initial evaluation to determine if the medical data 204 of the CTMDR 212 is suitable for further review/evaluation (step 112 ). For example, the CTAG 16 may have in-house resources to perform the initial review on the CTMDR 212 for completeness. Alternatively, the remote server 24 may have a plurality of software modules that evaluate the medical data 204 . For example, the CTMDR 212 may be unsuitable for further review/evaluation because the CTMDR 212 may be technically and/or clinically unusable. A technically unusable CTMDR 212 may include unclear information, partially damaged or corrupted files, or any other condition that would make the CTMDR 212 unreadable, unaccessible or technically unusable. A clinically unusable CTMDR 212 may indicate that the patient 10 is unsuitable for the clinical trial. For example, a specific clinical trial may require information from patients who suffer from tumors with diameters of 5 cm or larger; therefore, data from a patient with a tumor of 4.5 cm in diameter would be clinically unusable for this particular clinical trial.
[0024] In step 114 , access of the authorized participants to the unsuitable CTMDR 212 may be restricted by the CTAG 16 . Simultaneously, a request for transmittal or recollection of data may be sent to the medical facility 12 . One of the advantages of the present invention is that it eliminates a waste of resources for the evaluation if unusable medical data and expedites collection of the replacement medical data.
[0025] Upon receipt of the suitable CTMDR 212 , the remote server 24 notifies and provides access to the CTMDR 212 to the authorized participants of the clinical trial study (step 116 ). In step 118 , each of the authorized participants accesses and reviews the CTMDR 212 . Upon the review, the authorized participant generates a diagnostic report which is forwarded to the remote server 24 . The remote server 24 receives the diagnostic report and generates an updated CTMDR 218 (as shown in FIG. 4 b ). The remote server 24 also may send a receipt notification to the CTAG 16 that the updated CTMDR 218 was received.
[0026] There may not be a specified order of the review of the CTMDR 212 by the authorized participants. For example, the physician 8 and the medical evaluator 22 may access and evaluate the CTMDR 212 at the same time. Alternatively, the physician 8 may review the medical data 204 only after the medical evaluator 22 has submitted the diagnostic report. At this point, the physician 8 may access to the updated CTMDR 218 , which includes the diagnostic report 218 of the medical evaluator 22 , to further evaluate the medical data 204 .
[0027] The present invention further allows the CTAG 16 to more closely track the progress of the clinical trial study. In particular, prior to the client trial study, the CTAG 16 may formulate a clinical trial protocol (“CTP”) 300 , as seen in FIG. 5 . The CTP 300 may include the clinical trial study identifier 216 , a CTAG identification 302 , a preset procedure 304 , an authorized participant information 306 (e.g., an identifier of the physician 8 , the medical evaluator 22 , etc.), and a preset clinical trial schedule 308 . In other words, the CTP 300 provides a guideline for conducting the clinical study which is implemented by the remote server 24 . The CTP 300 may be updated by the CTAG 16 at anytime before or during the clinical trial study.
[0028] The clinical trial study identification 216 is the same as that which appears on the CTMDR 212 and updated CTMDR 218 . The clinical trial study identification 216 allows the CTAG 16 to differentiate between clinical trial studies, in the event that it is conducting multiple studies. Typically, the CTAG 16 determines the clinical trial study identification 216 , which may take the form of a number, word, alphanumeric identifier or phrase. Alternatively, the CTAG 16 may provide the clinical trial study identification 216 to the remote server 24 , which generates its own identification 216 .
[0029] The CTAG identification 302 included in the CTP 300 allows the remote server 24 to differentiate between and correspond with multiple CTAGs 16 in the event that it is conducting multiple clinical trial studies simultaneously and for multiple CTAGs 16 . The CTAG identification 302 may be generated by the remote server 24 or the CTAG 16 .
[0030] The CTP 300 may further include the preset procedures 304 and the preset schedule 308 which defined the schedule and procedure of the clinical trial study. The preset procedures 304 and the preset schedule 308 are specified by the CTAG 16 based on desired goals and specifics of the study. For example, the CTAG 16 may want the medical evaluator 22 to add its diagnostic report 218 to the CTMDR 212 before the physician 8 conducts his/her evaluation; the CTAG 16 may want to review the CTMDR 212 before the physician 8 so the CTAG 16 can ask questions based on the CTMDR 212 . Also, the CTAG 16 may have specified a time limit for the clinical trial study, or time limits for review by the medical evaluator 22 and/or physician 8 . As would be understood by those skilled in the art, the preset procedures 304 and the preset schedule 308 are customizable based on the desires of the CTAG 16 . The CTAG 16 may specify that when reminders to collect or review the medical data 204 must be sent to corresponding parties. The CTAG 16 may also set up due dates for follow up examinations of the patient 10 .
[0031] Further included in the CTP 300 is the authorized participant information 306 . The authorized participant information 306 may include the authorized participant's identification, a time for accessing the CTMDR 212 or updated CTMDR 218 , and/or a time for reporting based on the CTMDR 212 or updated CTMDR 218 . As would be understood by those skilled in the art, the authorized participant information 306 may further include as many or as few categories as the CTAG 16 deems necessary.
[0032] The authorized participant information 306 allows the remote server 24 to track the progress of the clinical trial study. For example, tracking data may be generated by monitoring the timing of access to the CTMDR 212 by authorized participants. The remote server 24 may compare the actual times of access with those in the preset schedule 308 to generate a progress report identifying delays and pointing to potential sources of the delay. For example, if the medical evaluator 22 is allotted 2 days to examine one CTMDR 212 , any time taken over the allotted amount may be noted in the progress report generated by the remote server 24 . Also, the remote server 24 may send a reminder notification or delay notice to the participant and the CTAG 16 . The progress report may further include instances where action was taken early. For example, if the medical evaluator completes review of several CTMDRs 212 in one day, this will be noted on the progress report. This tracking feature may allow the CTAG 16 to accurately assess delays in the clinical trial study and tailor incentives and/or penalties for the authorized participants. While the tracking feature has been described as being conducted by the remote server 24 , those skilled in the art would understand that the CTAG 16 and/or the monitoring facility 14 may track the clinical trial study.
[0033] Some of the CTAG guidelines/procedure may be generated during the study in the response to results obtained up to that particular point in the study. For example, results from the radiological data may generate predictions or recommendations for scheduling future patient testing based on a look up table of test results versus test schedules or other predetermined criteria.
[0034] While specific embodiments of the invention have been illustrated and described herein, it is realized that numerous modifications and changes will occur to those skilled in the art. It is therefore to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit and scope of the invention. | Described is a method and system for conducting a clinical trial. Medical data is obtained from a patient participating in the clinical trial. Then, the medical data and at least one identifier are transmitted, via a communications network, for storage at a remote server. The at least one identifier links the medical data to a record of the patient. Access to at least portions of the medical data is provided, via the communications network, to trial participants based on predefined clinical trial procedures. The remote server tracks accessing of the medical data by the trial participants and generation by the trial participants of work product responsive to the medical data. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates generally to an enhanced method and improved apparatus, device or devices, for the preparation of various organic compounds, such as: acids, aldehydes, amides, esters, ethers, and ketones. The invention relates more particularly to the use of a method and an apparatus, device or devices, such as a convergent divergent funnel mixer/reactor, for the production of aldehydes, amides, esters and ketones and, most particularly to the use of a convergent divergent funnel mixer/reactor for preparing aldehydes, such as meta-tolualdehyde (MTA), amides, such as N,N′-di-(ethyl)-meta-toluamide (DEET), esters, such as benzyl benzoate and ketones, such as methyl nonyl ketone (MNK), methyl cyclopropyl ketone (MCPK) and di-isopropyl ketone (DIPK). The invention also relates to using such organic compounds in the preparation of chemical, agricultural and pharmaceutical intermediates, pharmaceuticals, agricultural agents, herbicides, insecticides, pesticides, insect repellents, animal repellents, plasticizers, dye carriers and as flavor and/or fragrance ingredients.
[0003] 2. Description of the Prior Art
[0004] Numerous literature references cite and disclose various well-known processes for the preparation of ketones. These processes include oxidation of secondary alcohols; Friedel-Crafts acylation; reaction of acid chlorides with organic cadmium compounds; acetoacetic ester synthesis and decarboxylation from acids, among others.
[0005] Text and literature references also detail problems associated with these processes to produce ketones. These include problems such as the unavailability and/or high cost of raw materials, the requirement of multi-stage processing, the low conversion of raw materials and/or the low selectivity of the desired ketones, and the production of corrosive or hard-to-separate products.
[0006] Most ketone manufacturing processes include the reaction of various reactants at specified temperature and pressure ranges in the presence of a catalyst. For example,
[0007] U.S. Pat. No. 4,528,400 discloses a method of preparing unsymmetrical ketones by a catalytic vapor phase reaction using reactants such as ketones with carboxylic acids in the presence of a ceria-alumina catalyst. U.S. Pat. No. 4,874,899 involves the preparation of unsaturated and saturated ketones in the presence of a catalyst such as a zeolite, a phosphate having a zeolite structure and/or a B, Ce, Fe, Zr or Sr phosphate. U.S. Pat. No. 4,570,021 relates to the preparation of ketones utilizing a ceria-alumina catalyst. U.S. Pat. No. 4,060,555 discloses the production of a class of aliphatic ketones in the presence of Deacon Catalysts. U.S. Pat. No. 3,966,822 discloses the preparation of ketones from aldehydes in the presence of zirconium oxide and various other catalysts. U.S. Pat. No. 3,466,334 discloses synthesis of ketones from an aldehyde and an acid in the presence of a catalyst comprised of an alumina-supported oxidized form of lithium. U.S. Pat. No. 3,453,331 discloses a process for the synthesis of ketones from aldehydes using various alumina-supported oxidized forms of various metals. German Patent Application, No. P 36 37 788.0 discloses a process for the preparation of a ketone in the presence of catalysts such as ZnO and/or CeO 2 doped on aluminum oxide (Al 2 O 3 ).
[0008] U.S. Pat. No. 6,369,276 B1; U.S. Pat. No. 6,392,099 B1; U.S. Pat. No. 6,482,991 B2; U.S. Pat. No. 6,495,696 and U.S. Pat. No. 6,545,185 address the need in the art for a catalyst or catalyst structure useful in the production of ketones and aldehydes which not only allows the reaction to proceed, but which also optimizes the conversion and selectivity of the reaction to the desired ketone or aldehyde and permits conversion and selectivity for various catalyst structures to be reasonably predicted. They also address the method of making such a catalyst and for using such a catalyst in the production of ketones and aldehydes. The catalyst structure includes a substantial theoretical monolayer (TML) of catalyst on a catalyst support to optimize yield and weight hourly space velocities (WHSV). As used with these patents, the term theoretical monolayer (TML) is a thin film or layer of a material (catalyst) applied to a surface (catalyst support) at a thickness of one molecule and a substantial theoretical monolayer means plus or minus 10% of a theoretical monolayer.
[0009] These patents also describe the use of preferably conventional stainless steel tube reactors, where the available reaction volume, is filled with various combinations of an inert filler material, and a theoretical monolayer catalyst. Available Reaction Volume (ARV) is the total (inside) volume of the tube reactor. The inert filler material is comprised of glass beads, stainless steel beads, lava rock and sand, among possible others. The distribution of the catalyst within the available reaction volume can vary. Preferably, however, the method and use of these patents claim, the bottom ⅓ of the reactor is filled with inert material in the form of glass beads, the middle third of the reactor is filled with a catalyst and the top ⅓ of the reactor could be empty or filled with glass beads or another inert material. U.S. Pat. No. 4,570,021 and U.S. Pat. No. 4,528,400 also describe the use of glass beads, in a tube reactor, ahead of and behind the catalyst zone.
[0010] International Publication Number WO 02/36559 A2 discloses, in the preferred embodiment, the invention of a process for the production of N,N-di(ethyl)-meta-toluamide comprising: (a) reacting meta-xylene and oxygen to form meta-toluic acid, wherein the reaction occurs in the liquid or vapor phase and in the presence of a first catalyst; (b) separating the meta-toluic acid from the mixture formed in step (a), wherein the meta-toluic acid is maintained in a liquid or vapor phase; and (c) reacting the meta-toluic acid with diethylamine to form N,N-di(ethyl)-meta-toluamide, wherein the reaction occurs in the vapor phase and in the presence of a second catalyst, in one or more tube reactors, using a theoretical monolayer catalyst and inert filler material.
[0011] Numerous patents have been issued for converging and/or diverging nozzles, with a wide variety of applications, such as laser devices, venting means for nuclear reactors, combustion and/or turbo-jet mufflers, flow bodies, animal feed device, reactors for the production of salts and fast quenching reactors, among others. U.S. Pat. No. 6,284,189 B1 describes a nozzle device to inject oxygen and technological gases used in metallurgical processing of metal melting, the nozzle being suitable to emit a gassy flow at supersonic velocity, the nozzle having a conformation symmetrical to a central axis (x) defined by a throat arranged between the inlet and the outlet, the throat defining an upstream part with a convergent development and a downstream part with a divergent development which ends in the outlet mouth, the nozzle with the convergent/divergent development having a geometry such that the fall in pressure of the gassy flow from inlet to outlet has a hyperbolic tangent development. It also describes a dimensioning method for the nozzle as above, the method providing an inverse dimensioning approach wherein the geometry of the nozzle is adapted to the natural profile of the fall in pressure of the gassy flow according to a hyperbolic tangent development, thus obtaining an optimum variation of the aerodynamic parameters according to the natural laws of expansion.
[0012] However, the dimensioning method for the converging diverging nozzle is meant to optimize the gassy flow at supersonic velocity and does not address the need in the art for subsonic irregular or turbulent flow in the converging diverging transition section to promote mixing of raw materials, which are then used in a chemical process.
[0013] U.S. Pat. No. 6,437,001 B1 describes the use of an unsymmetrical ketone as an active ingredient to repel insects; however, it does not address the need for a more cost effective manufacturing process for these active ingredients, to compete with existing repellent products.
[0014] U.S. Pat. No. 6,524,605 B1 describes the use of a Monoterpenoids, such as Nepetalactone, derived from a biorational source, such as a plant volatile; but does not address the need for a more cost effective chemical manufacturing process for these active ingredients; to repel arthropods, such as termites.
[0015] In examples, U.S. Pat. No. 6,369,276 B1 and many others; describe the ratio of raw materials, which makes up the feed stream or feed material, as preferably in the range of 2:1 to 20:1; more preferably, the ratio of about 3:1 to 8:1 and most preferably within a range of 3:1 to 5:1. The most preferred ratio is about 4:1. Using an excess of the least expensive raw material is common practice in the chemical industry; with a driving force being; to “use-up” or consume ˜100% of the most expensive raw material. However, this practice results in excess production of co-products and/or the separation and recovery of the un-reacted raw material that passes through the reactor. This excess raw material ratio also has an effect on the optimum WHSV.
[0016] Although a great deal of attention has been given to the use of convergent and/or divergent funnels and nozzles; to catalyst and catalyst structure, to the method of making a catalyst; to the ratio of the raw material feed; to process parameters, such as temperature and pressure; in connection with the production of acids, aldehydes, amides, esters, ethers and ketones; little, if any, attention has been given to the inert filler material or to the distribution of the catalyst and inert filler material inside the available reaction volume (ARV), of a tube reactor, to optimize yield (raw material conversion and selectivity) to the desired product. In addition, little attention has been given to raw material mixing, as well as to the optimum (theoretical stoichiometric) raw material ratio (r 1t :r 2t ) on the weight hourly space velocity in a tube reactor process.
[0017] Accordingly, there is a need in the art for an enhanced method and apparatus, device or devices, to provide mixing of the feed materials, to optimize the available reaction volume (ARV); the raw material feed ratios (R1:R2) and the weight hourly space velocity (WHSV) which provides for a significantly improved production rate and cost of organic compounds including: acids, aldehydes, amides, esters, ethers and ketones; and particularly, esters, such as benzyl benzoate, amides, such as N,N-di(ethyl)-meta-toluamide (DEET) and ketones, such as methyl nonyl ketone (MNK), methyl cyclopropyl ketone (MCPK) and di-isopropyl ketone (DIPK); which are useful as chemical, agricultural and pharmaceutical intermediates, pharmaceuticals, agricultural agents, herbicides, insecticides, pesticides, insect repellents, animal repellents, plasticizers, dye carriers and as flavor and/or fragrance ingredients.
SUMMARY OF THE INVENTION
[0018] In contrast to the prior art, the present invention relates generally to a method and apparatus, device or devices, for the preparation of various organic compounds, such as: acids, aldehydes, amides, esters, ethers, and ketones. The invention relates more particularly to the use of a device or devices, such as a convergent divergent funnel mixer/reactor, for the production of aldehydes, amides, esters and ketones and most particularly to the use of a device or devices, such as a convergent divergent funnel mixer/reactor, for preparing aldehydes, such as meta-tolualdehyde (MTA), amides, such as N,N-di(ethyl)-meta-toluamide (DEET); esters, such as benzyl benzoate and ketones, such as methyl nonyl ketone (MNK), methyl cyclopropyl ketone (MCPK) and di-isopropyl ketone (DIPK); which overcomes limitations of the prior art. The invention also relates to using such aldehyde, amide, ester and ketone preparation in the preparation of insect repellents, animal repellents, chemical intermediates, herbicidal or other agricultural compounds and as flavor and/or fragrances ingredients.
[0019] Specifically, the method and apparatus, device or devices, of the present invention utilizes readily available and inexpensive raw materials, results in high conversion and selectivity and provides for increased production of the desired products. Generally, the raw materials used in the method and apparatus of the present invention include: aromatic or aliphatic hydrocarbons, acids or aldehydes or their derivatives, alcohols, amines, carboxylic acids, oxygen or an oxygen source. More specifically, the present invention involves the preparation of aldehydes, such as meta-tolualdehyde (MTA), amides, such as N,N-di(ethyl)-meta-toluamide (DEET); esters, such as benzyl benzoate and ketones, such as methyl nonyl ketone (MNK), methyl cyclopropyl ketone (MCPK) and di-isopropyl ketone (DIPK), utilizing a tube reactor provided with a suitable catalyst. For purpose of this application and method, the catalyst is a super-layer catalyst; defined as greater than 110% of a theoretical mono-layer. The preferred raw materials or feed materials include, but or not limited to: benzoic acid, benzyl alcohol, meta-toluic acid (MTA), diethylamine (DEA), decanoic acid, cyclopropylaldehyde or its derivatives (such as cyclopropanecarboxylic acid), butyric acid and acetic acid which are readily available through processes known in the art. Depending on the desired organic compound, the properly selected, gas phase raw materials are fed into and through a device or devices, such as a convergent divergent funnel mixer, attached to a tube reactor, where they are exposed to a catalyst and react to produce the desire product.
[0020] By adding a device or devices, such as a convergent divergent funnel, as a raw material mixer, to a tube reactor process, the present invention allows for a 100-200% increase in the available reaction volume (ARV). Previous art requires the use of an inert filler material, inside the reactor, ahead of and an inert filler material or empty space behind the catalyst. This inert filler material, which occupies reaction volume, is comprised of glass beads, stainless steel beads, lava rock and sand, among possible others. The distribution of the inert filler material within the available reaction volume (ARV) can vary greatly; however, previous patents “preferably” require the bottom ⅓ and the top ⅓ of the available reaction volume (ARV) to be empty or filled an inert material. The purpose of this inert filler material, before the catalyst, is to provide a zone for mixing and/or heating of the raw materials before they reach the catalyst.
[0021] For some tube reactor processes, it could be impossible to increase the WHSV, because the inert filler material zone does not provide sufficient volume and time to allow for complete mixing and heating of the raw materials before they reach the catalyst. For example; Using a pre-mixed liquid feed at 30° C., WHSV=20; in a nine (9′) foot long, six (6″) inch diameter, tube reactor, with a configuration of ⅓ glass beads, ⅓ catalyst (48.5 lbs/ft 3 ) and ⅓ glass beads, reaction temperature of 330° C.; would need ten (10) pounds of raw material feed to be heated (ΔH=˜300° C.) and mixed, in the 36 inch long inert filler zone before the catalyst, in only twenty (20) seconds! Feeding separate pre-heated, raw materials would help; however the mixing could still be incomplete.
[0022] Pre-heating a theoretical stoichiometric ratio (TSR) of raw materials and feeding these raw materials into a device, such as the converging section of a converging diverging funnel mixer, would allow for complete mixing and a greatly increased WHSV.
[0023] During catalyst change-over or routine reactor maintenance, when the reactor is reloaded with new inert filler material and catalyst, the flow of material through the available reaction volume is, more often than not, changed. The new inert filler material can be more or less tightly packed or have different surface characteristics, which would causes the flow channels (voids) within the inert filler material zone and catalyst zone to change. Changing conditions within the inert filler material zone are a disadvantage to the process and have a negative effect on process controls, such as raw material mixing, temperature and pressure, and on the actual conversion and yield.
[0024] By the addition of a mixing device or devices, such as a converging diverging funnel mixer, to the tube reactor and removal of the inert filler material before the catalyst, the volume of the catalyst zone can be increased by as much as 100%. This allows for approximately 60-70% of the total available reaction volume (ARV) to be loaded with catalyst. The use of a device or devices, such as a converging diverging funnel mixer, also allows for constant, measurable and controllable mixing parameters.
[0025] After the catalyst zone, the inert filler material is used to hold the catalyst in position, provides a head-space, or a reaction quenching and cooling zone for the products and co-products. Depending on the reaction conditions, determining the optimum requirements for the inert filler material volume, after the catalyst zone, could allow for the loading or addition of an additional 30-40% of catalyst, in the available reaction volume.
[0026] In the preferred embodiment and method of the present invention, the reactor is a gas/vapor phase tube reactor and attached to the divergent section of a convergent divergent funnel mixer, in contrast to a condensation reactor or a batch stirred (mixed) reactor. Since some chemical reactions will be exothermic and others will be endothermic, the tube reactor and the convergent divergent funnel mixer are provided with an external heat and cooling source, as well as insulation. The reactant materials are pre-heated to the gas/vapor phase. Pre-heating equipment is available from companies skilled in the art, such AccuTherm, Inc. Monroe City, Mo., U.S.A.
[0027] Further, in the enhanced method and improved apparatus of the present invention the reactant materials, in a theoretical stoichiometric ratio (TSR), are fed into a device or devices, such as the convergent section of the funnel mixer with sufficient pressure to cause flow through the convergent divergent transition section of the mixer, where the significantly increased velocity and turbulent flow created by the converging section of the funnel causes mixing of the raw material. The theoretical stoichiometric raw material mixture then pass through the divergent section of the funnel mixer, into the reactor, which contains sufficient catalyst to fill the available reaction volume (ARV). With this configuration, it is possible to dramatically reduce excess raw material consumption, minimize production of co-products, maximize use of the reactor capacity and greatly increase the WHSV. This results in significantly increased production rates and lower cost.
[0028] An object of the present invention is to provide for using the above described enhanced method and improved apparatus, device or devices, for the preparation of: chemical, agricultural and pharmaceutical intermediates, pharmaceuticals, agricultural agents, herbicides, insecticides, pesticides, insect repellents, animal repellents, plasticizers, dye carriers and flavor and/or fragrance ingredients.
[0029] Accordingly, an object of the present invention is to provide an enhanced method and improved apparatus, device or devices, for the preparation of aldehydes, amides, esters and ketones and in particular aldehydes, such as meta-tolualdehyde (MTA), amides, such as N,N-di(ethyl)-meta-toluamide (DEET), esters, such as benzyl benzoate and ketones, such as methyl nonyl ketone (MNK), methyl cyclopropyl ketone (MCPK) and di-isopropyl ketone (DIPK).
[0030] A further object of the present invention is to provide an enhanced method and improved apparatus, device or devices, for the preparation of MTA, DEET, Benzyl Benzoate, MNK, MCPK or DIPK at high conversion rates and high selectivity, with a minimum of undesirable co-products.
[0031] A still further object of the present invention is to provide an enhanced method and improved apparatus, device or devices, for the preparation of meta-tolualdehyde (MTA), N,N-di(ethyl)-meta-toluamide (DEET), benzyl benzoate, methyl nonyl ketone (MNK), methyl cyclopropyl ketone (MCPK) and di-isopropyl ketone (DIPK), at dramatically increased production rates and lower cost.
[0032] These and other objects of the present invention will become apparent with reference to the drawings, the definitions, the description of the preferred embodiment and the appended claims.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0033] Reference is made to Drawing 1 , where the apparatus, device or devices, is a symmetrical converging diverging funnel mixer with an inside diameter of six (6) inch, at the mouth; and a transition diameter of three-fourth (¾) inch, between the converging and diverging sections. The diagram shows flow of two (2) separate raw materials, which have been pre-heated to gas phase. The two materials enter into the converging section in a substantial theoretical stoichiometric ratio, at a velocity (v 1 ). The flow velocity accelerates, as the raw materials approach and passes into the transition section at a velocity (v 2 ), according to the formula:
v 2 =v 1 *( r 1 /r 2 ) 2
[0034] This exponential increase in velocity causes turbulent flow, and results in a mixing of the two raw materials. Pressure in the funnel mixer and reactor is controlled to maintain the raw material feed in a gas phase.
[0035] Reference is made to Drawing 2 , which shows a stainless steel gas phase tube reactor connected to a mixing device. The reactor is connected to the diverging section of a symmetrical converging diverging funnel mixer, which is constructed of hastelloy alloy.
[0036] As the mixed raw material feed passes out of the diverging section, it enters into the catalyst zone in the tube reactors available reaction volume (ARV). For this example, the total available reaction volume (ARV) of the tube reactor is filled with a super-layer catalyst, suitable for the process. External heating or cooling and insulation are used to maintain the catalyst zone at the appropriate reaction temperature. In the presence of heat and catalyst, the theoretical stoichiometric mixed ratio raw materials react to form the desired product.
[0037] The desired product and co-products then pass out of the tube reactor into product receiver equipment for recovery, separation and distillation.
EXAMPLE
[0038] Reference is made to Drawing 1 , where the apparatus, device or devices, is a symmetrical converging diverging funnel mixer with an inside radius of three (3) inch, at the mouth; and a transition radius three-eights (⅜) inch, between the converging and diverging sections. The diagram shows flow of two (2) separate gas phase raw materials (acetic acid and decanoic acid), which have been pre-heated to ˜300° C. The two acids enter into the converging section in a substantial theoretical stoichiometric ratio of 1.4:1.0, at a flow velocity (v 1 ) of 20 pounds per minute. The flow velocity accelerates, as acids approach; pass into and through the transition section at a velocity (v 2 ) of ˜1280 pounds per minute, according to the formula:
v 2 =v 1 *( r 1 /r 2 ) 2
[0039] This exponential increase in velocity causes turbulent flow, and results in a complete stoichiometric mixings of the two acids. Pressure in the funnel mixer and reactor is controlled at 120-150 psig, to maintain the mixed acids in a gas phase.
[0040] Reference is made to Drawing 2 , which shows a six (6) inch diameter, ten (10) foot long stainless steel gas phase tube reactor connected to the diverging section of a symmetrical converging diverging funnel mixer, which is constructed of hastelloy alloy.
[0041] As the mixed acids pass through and out of the transition section of the converging diverging mixer; the flow velocity (V 3 ) decelerates; to ˜20 pounds per minute, according to the formula:
v 3 =v 2 *( r 2 /r 3 ) 2
[0042] The mixed acids enter into the catalyst zone in the tube reactors available reaction volume (ARV) (WHSV=14), which is filled with ˜82 pounds of a CeO 2 /Al 2 O 3 super-layer catalyst with a bulk density of 42.5 lb/ft3. External heating or cooling and insulation are used to maintain the catalyst zone at ˜305° C. In the presence of heat and catalyst, the theoretical stoichiometric mixed acids react to form a crude mixture: methyl nonyl ketone (MNK) and the corresponding co-products.
[0043] The crude MNK and co-product mixture then pass out of the tube reactor into a product receiver for recovery, separation and distillation. Conversion of the raw material feed acids is typically 97%±, with selectivity to MNK, the unsymmetrical ketone, of 90%±.
EXAMPLE
[0044] Reference is made to Drawing 1 , where the apparatus, device or devices, is a symmetrical converging diverging funnel mixer with an inside radius of three (3) inch, at the mouth; and a transition radius three-eights (⅜) inch, between the converging and diverging sections. The diagram shows flow of two (2) separate gas phase raw materials (acetic acid and cyclopropanecarboxylic acid), which have been pre-heated to ˜310° C. The two acids enter into the converging section in a substantial theoretical stoichiometric ratio of 1.6:1.0, at a flow velocity (v 1 ) of 30 lb/min [Re=1500]. The flow velocity accelerates as the acids approach; pass into and through the transition section, at a velocity (v 2 ) of ˜1900 lb/min [Re=3500], according to the formula:
v 2 =v 1 *( r 1 /r 2 ) 2
[0045] This exponential increase in velocity causes turbulent flow [Re=3500], and results in a complete stoichiometric mixings of the two acids. Pressure in the funnel mixer and reactor is controlled at 120-150 psig, to maintain the mixed acids in a gas phase.
[0046] Reference is made to Drawing 2 , which shows a six (6) inch diameter, ten (10) foot long stainless steel gas phase tube reactor connected to the diverging section of a symmetrical converging diverging funnel mixer, which is constructed of hastelloy alloy.
[0047] As the mixed acids pass through and out of the transition section of the converging diverging mixer; the flow velocity (v 3 ) decelerates; to ˜30 lb/min [Re=1800], according to the formula:
v 3 =v 2 *( r 2 /r 3 ) 2
[0048] The mixed acids enter into the catalyst zone in the tube reactors available reaction volume (ARV) (WHSV=20), which is filled with ˜90 pounds of a CeO 2 /Al 2 O 3 super-layer-catalyst with a bulk density of 46.8 lb/ft3. External heating or cooling and insulation are used to maintain the catalyst zone at ˜310° C. In the presence of heat and catalyst, the theoretical stoichiometric mixed acids react to form a crude mixture: methyl cyclopropyl ketone (MCPK) and the corresponding co-products.
[0049] The crude MCPK and co-product mixture then pass out of the tube reactor into a product receiver for recovery, separation and distillation. Conversion of the raw material feed acids is typically 98%+, with selectivity to MCPK, the unsymmetrical ketone, of 89%+.
EXAMPLE
[0050] The ketones produced by the improved apparatus and enhanced method of the present invention can be distilled and combined with other processes to produce various herbicidal or other agricultural compounds. Preferably, the ketone production method of the present invention can be used, in combination with other process steps, to prepare such a compound of the formula (I)
wherein:
[0051] R 1 is cycloalkyl having from three to six ring carbon atoms which is un-substituted or which has one or more substituents selected from the group consisting of R 4 and halogen;
[0052] R 2 is halogen; straight- or branched-chain alkyl having up to six carbon atoms which is substituted by one or more —OR 5 ; cycloalkyl having from three to six carbon atoms; or a member selected from the group consisting of nitro, cyano, —CO 2 R 5 , —NR 5 R 6 , —S(O) p R 7 , —O(CH 2 ) m OR 5 , —COR 5 , —N(R 8 )SO 2 R 7 , —OR 7 , —OH, —OSO 2 R 7 , —(CR 9 R 10 ) t SO q R 7a , —CONR 5 R 6 , —N(R 8 )—C(Z)Y, —(CR 9 R 10 )NR 8 R 11 and R 4 ;
[0053] n is zero or an integer from one to three; when n is greater than one, then the groups R 2 are the same or different;
[0054] m is one, two or three;
[0055] p is zero, one or two;
[0056] q is zero, one or two;
[0057] t is an integer from one to four;
[0058] R 3 is straight- or branched-chain alkyl group containing up to six carbon atoms which is un-substituted or which has one or more substituents selected from the group consisting of halogen, —OR 5 , —CO 2 R 5 , —S(O) p R 7 , phenyl or cyano; or phenyl which is unsubstituted or which has one or more substituents selected from the group consisting of halogen, —OR 5 and R 4 ;
[0059] R 4 is straight- or branched-chain alkyl, alkenyl or alkynyl having up to six carbon atoms which is un-substituted or is substituted by one or more halogen;
[0060] R 5 and R 6 , which are the same or different, are each hydrogen or R 4 ;
[0061] R 7 and R 7a independently are R 4 , cycloalkyl having from three to six ring carbon atoms, or —(CH 2 ) w -phenyl wherein phenyl is un-substituted or is substituted by from one to five R 12 which are the same or different;
[0062] w is zero or one;
[0063] R 8 is hydrogen; straight- or branched-chain alkyl, alkenyl or alkynyl having up to ten carbon atoms which is un-substituted or is substituted by one or more halogen; cycloalkyl having from three to six ring carbon atoms; —(CH 2 ) w -phenyl wherein phenyl is un-substituted or is substituted by from one to five R 12 which are the same or different; or —OR 13 ;
[0064] R 9 and R 10 independently are hydrogen or straight- or branched-chain alkyl having up to six carbon atoms which is un-substituted or is substituted by one or more halogen;
[0065] R 11 is —S(O) q R 7 or —C(Z)Y;
[0066] R 12 is halogen; straight- or branched-chain alkyl having up to three carbon atoms which is un-substituted or is substituted by one or more halogen; or a member selected from the group consisting of nitro, cyano, —S(O) p R 3 and —OR 5 ;
[0067] Y is oxygen or sulphur;
[0068] Z is R 4 , —NR 8 R 13 , —NR 8 —NR 13 R 14 , —SR 7 or —OR 7 ; and
[0069] R 13 and R 14 independently are R 8 ,
[0070] or an agriculturally acceptable salt or metal complex thereof,
[0071] The process for preparing a compound of the above formula (I) comprises:
[0072] (i) reacting a compound of formula (II)
wherein R 15 is a straight- or branched-chain alkyl group having up to six carbon atoms with a compound of formula (III)
in an aprotic solvent in the absence of a base to form a compound of formula (IV)
(ii) reacting a compound of formula (IV) with a compound that contains a leaving group L [such as alkoxy or N,N-dialkylamino, esp. ethoxy and CH(OCH 2 CH 3 ) 3 to form a compound of formula (V)
(iii) reacting a compound of formula (V) with hydroxylamine or a salt of hydroxylamine to form a compound of formula (I),
[0073] wherein the process further comprises producing the compound of formula (III) by:
[0074] providing gas phase raw materials, in a substantial theoretical stoichiometric ratio, to the converging section of a converging diverging funnel mixer;
[0075] wherein said gas phase raw materials are mixed by the significantly increased velocity and turbulent flow as they pass through the converging section and approach the transition section of the convergent divergent funnel mixer;
[0076] wherein said mixed raw materials pass through and out of the diverging section of the funnel mixer and into the tube reactor;
[0077] wherein the available reaction volume (ARV) of the tube reactor contains a super-layer catalyst;
[0078] wherein the mixed raw materials, in a substantial theoretical stoichiometric ratio pass through the catalyst, in the available reaction volume (ARV), to product the desired organic compound;
[0079] separating and recovering the desired organic compound.
[0080] In the above process, the compound of formula (III) is a ketone produced in accordance with an enhanced method and improved apparatus, device or devices, for preparing various organic compounds, such as ketones in accordance with of the present invention.
EXAMPLE
[0081] The enhanced method and improved apparatus, device or devices, for preparing various organic compounds can also be used, in combination with other process steps, to prepare a compound of the following formula (X)
[0082] The specific process steps comprise:
[0083] (i) reacting a compound of formula (XI)
with a compound of formula (XII)
to form a compound of formula (XIII)
(ii) reacting a compound of formula (XIII) with CH(OCH 2 CH 3 ) 3 to form a compound of formula (XIV)
(iii) reacting a compound of formula (XIV) with hydroxylamine or a salt of hydroxylamine to form a compound of the formula (XV)
(iv) reacting a compound of formula (XV) with chloroperbenzoic acid [or an equivalent] to form a compound of the formula (X);
[0084] wherein the process further comprises producing the compound of formula (XII) by;
[0085] using an enhanced method and improved apparatus, device or devices, for preparing various organic compounds, such as ketones in accordance with of the present invention.
[0086] In the above process, the compound of formula (XII) is methyl cyclopropyl ketone (MCPK).
[0087] Further details of compounds of formula (I) and formula (X) described above are known in the art and described in one or more of PCT Publication No. WO 99/02476, U.S. Pat. No. 5,366,957 and U.S. Pat. No. 5,849,928; the substance of which is incorporated herein, by reference.
[0088] Although, the description of the preferred embodiment and method has been quite specific, it is contemplated that various modifications to the apparatus, device or devices, could be made without deviating from the spirit of the present invention. Nozzles, Injection Mixers, Vortex Mixers, Fan Blades and Baffles are examples of other types of mixing devices. Accordingly, it is intended that the scope of the present invention be dictated by the appended claims, as well as the description of the preferred embodiment. | A method of using an apparatus, device or devices, such as a convergent divergent funnel, as a mixer for the feed material, to optimize the available reaction volume (ARV), the raw material feed ratios (R1:R2) and the weight hourly space velocity (WHSV), to produce organic compounds, in a tube reactor. These organic compounds include, but are not limited to: acids, aldehydes, amides, esters, ethers and ketones, which are useful as chemical, agricultural and pharmaceutical intermediates, pharmaceuticals, agricultural agents, herbicides, insecticides, pesticides, insect repellents, animal repellents, plasticizers, dye carriers and as flavor and/or fragrance ingredients. | 2 |
FIELD OF THE INVENTION
This invention pertains to the production of optically anisotropic pitch useful for carbon fiber production.
BACKGROUND OF THE INVENTION
Optically anisotropic pitches that can be spun into carbon fibers have been produced previously by heat soaking an aromatic feedstock containing polycondensed aromatic (3, 4, 5, 6 and 7) rings or by heating a petroleum pitch containing larger aromatic rings. During the heat soaking treatment polycondensed aromatic rings will polymerize and condense into aromatic ring agglomerates called liquid crystals (mesophase) which are 100% optically anistropic when polished sections are examined by polarized light microscopy.
Highly anisotropic pitches prepared from aromatic feed or from petroleum pitch contain unreacted oils, often in substantial amounts (25-35%). These oils must be almost completely removed to produce a pitch with the desired rheological properties such as softening point and viscosity; which are critical parameters for successful spinning, oxidation, carbonization treatments of the green fiber in the production of high tensile strength carbon fibers.
Removal of the unreacted oil from the heat soaked feed mixture can be achieved by many methods including vacuum stripping the unreacted oil at the end of the heat soaking step. This can be carried out by using the same heat soaking reactor. Such a method of oil removal has been used effectively to prepare aromatic pitches from steam cracker tar, catalytic cracking bottom and coal by-products. The preparation of these pitches are described in the following U.S. patents and patent applications: Pat. No. 4,086,156 (1978); Ser. No. 225,060 (1981); Ser. No. 346,624 (1982); Ser. No. 346,623 (1982); Ser. No. 399,751 (1982); Ser. No. 399,472 (1982); and Ser. No. 399,702 (1982).
Another method of removing the unreacted oils calls for conducting the heat soaking under reduced pressure, where these unreacted oil are removed continuously during the heat soaking step. This procedure for pitch preparation is described in U.S. Pat. No. 4,271,006 (1981).
A further method for removing the unreacted oil from the heat soaking mixture is by injection of an inert gas at the bottom of the heat soaked mixture to volatilize the light, distillable oils. The oil stripping efficiency and rate of oil removal will, of course, be dependent on the design of the reactor and the distillate recovery system, the rate that the inert gas is passed into the mixture, the design of the sparger, as well as the rate of agitation. A major objective of the present invention is to make maximum utilization of the stripping gas in such a process.
U.S. Pat. No. 3,974,264 (McHenry) describes such a process for producing a pitch with a high mesophase content using a substantially shorter time by passing an inert gas through the heated pitch (350°-450° C.) during the formation of the mesophase at a rate of at least 0.5 SCFH/lb of pitch and generally at a rate of 0.7 to 5.0 SCFH/lb of pitch.
A later U.S. Pat. No. 4,209,500 (Chwastiak) describes the production of an aromatic pitch with high optical anisotropy by heating a petroleum pitch feed at 380°-430° C. and passing nitrogen through the heat soaked mixture at a rate of at least 4.0 SCFH/lb of pitch and up to 10.0 SCFH/lb of pitch. This patent asserts that an improved process for aromatic pitch production with 100% optical anisotropy is achieved by increasing the rate of which the nitrogen gas is passed into the heat soaked mixture for efficient stripping of the unreacted distillable oils thereby increasing the rate of mesophase formation.
As we indicated above, the degree of oil stripping from a heat soaked mixture depends on the rate of inert gas injection into the bottom of the reactor. It now has been found that the stripping of oils is also dependent on a number of other operating conditions.
SUMMARY OF THE INVENTION
In accordance with the present invention it has been found that the rate of mechanical agitation is as important as the nitrogen gas feed rate for increasing the rate of optical anisotropic development in the pitch during heat soaking. Increased inert gas injection into the molten pitch can soon reach a maximum in the absence of efficient dispersion of the gas into the molten pitch. It also has been found that efficient agitation can produce pitches with 100% mesophase content with a low nitrogen rate injection i.e., 2.5 SCFH/lb of pitch, which is below what U.S. Pat. No. 4,209,500 states to be too low and ineffective.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a reactor for heat soaking and for removing unreacted oils from pitches from aromatic feed or petroleum pitch.
FIG. 2 is a side view of the gas sparger provided with a nitrogen gas feed line and a sparger ring.
FIG. 3 is a bottom view of the gas sparger shown in FIG. 2 and the gas exit holes positioned on the bottom side of the ring.
FIG. 4 is a graph illustrating optical anisotropy formation based on the rate of agitation.
DETAILED DESCRIPTION OF THE INVENTION
The effect of agitation on optical anisotropic development was demonstrated by heat soaking a commercial petroleum pitch (Ashland 240) with nitrogen injection at the bottom of an electrically heated reactor equipped with an agitator of which the rate of agitation can vary from about 200-600 rpm, preferably from about 300 to 550 rpm. The nitrogen gas was injected at the bottom of the reactor using a gas sparger designed to ensure efficient gas distribution into the molten pitch.
The design of the type of sparger for the present invention is illustrated in FIGS. 1 through 3 where an electrically heated glass reactor 1 is provided with a gas sparger ring 2 connected to a nitrogen feed line 3. Positioned above gas sparger 2 is an agitator 4 provided with blades 5 and driven by stirring motor 6. Reactor is also equipped with a thermocouple 7 for accurate measurement of the heat soaking temperature and a condenser 8 for recovering the unreacted hydrocarbon oils.
The agitator blades 5 are placed immediately above sparger ring 2 to distribute efficiently the nitrogen gas from the sparger into the molten pitch to effect stripping of the unreacted oil while controlling agitation by varying the rpm of agitator blades 5.
The present invention will be more fully understood by reference to the following illustrative embodiments.
EXAMPLES 1, 2, 3, 4 and 5
675 grams of Ashland Petroleum Pitch 240 were introduced into a one liter reactor. The Ashland pitch had the following characteristics:
______________________________________Softening point, °C. 122.4Density 1.230Coking Valve (%) 52.0Flash Point, °C. 290Sulfur Content (wt %) 1.40Toluene Insolubles (%) 7.4Quinoline Insolubles (%) 0.14______________________________________
As shown in FIG. 1 the reactor was equipped with a gas sparger ring 2 which is placed at the bottom of the reactor 1, an agitator 4 with blades 5 placed immediately above the sparger, a thermocouple 7 for controlling the pitch temperature, and a condensor 8 to recover hydrocarbon material leaving the reactor 1. The nitrogen gas feed line 3 was made 1/4 inch O.D. Type 304 stainless steel tubing that was bent to form a gas sparger ring 2 having a diameter of 2.5 inches and four 0.015 orifices on the botton side of the ring at approximately 90 degree spacings. The gas feed or supply line had a 3 length of about 8 to 10 inches.
The Asland pitch in the reactor was heat soaked at 400° C. for 12 hours at atmospheric pressure with the agitation rate of 330 rpm. The nitrogen rate injected at the bottom of the reactor was varied 1.5, 3.0, 3.5, 4.0, and 5.0 SCFH/lb of pitch, respectively, for each run. The pressure of the nitrogen used for stripping was 80.0 psig. When heat soaking was completed, the molten pitch was cooled under nitrogen atmosphere to room temperature. The pitch produced was characterized by the following methods:
(a) Regular Toluene Insolubles (RTI)--10 grams of sample and 500 cc of toluene reflexed for one hour and then filtered through medium glass filter.
(b) Regular Pyridine Insolubles (RPI)--2 grams sample and 100 cc pyridine refluxed for one hour and filtered (medium filter).
(c) Quinoline Insolubles (QI)--One gram sample and 25 cc quinoline shaked for 4.0 hours at 75° C. and filtered (medium filter).
(d) Pyridine Insolubles (Soxhlet method)--2.5 grams (80-100 mesh) of the pitch were placed in a glass soxhlet and extracted with refluxing pyridine for 24 hours.
(e) Optical Anisotropy (OA %)--polished sections of the pitch were examined by cross polarized light microscopy (with ×10).
The results obtained using nitrogen injection rates 1.5, 3.0, 4.0 and 5.0 SCFH/lb of pitch are given below:
TABLE A__________________________________________________________________________ HEAT SOAKING CONDITIONS PITCH ANALYSES FEED NITROGEN REGULAR SOXHLET CHARGE RATE AGITATION TEMP. TIME RPI RPI OAEXAMPLE (gms) (SCFH/lb) (RPM) (°C.) (HRS) (%) (%) (%)__________________________________________________________________________1 675 1.5 330 400 12 19.0 36.6 252 675 3.0 330 400 12 31.8 44.6 953 675 3.5 330 400 12 -- -- 954 675 4.0 330 400 12 44.6 50.3 1005 675 5.0 330 400 12 54.8 59.3 100__________________________________________________________________________
EXAMPLES 6, 7 and 8
Pitch production was repeated using the method described in Examples 1 through 5 with one execption: A higher rate of agitation (530 RPM). Pitch production was repeated using 2.0, 2.5 and 3.0 SCFH/lb of nitrogen. Pitch analysis is as follows:
TABLE B__________________________________________________________________________ HEATING SOAKING CONDITIONS PITCH ANALYSES FEED NITROGEN REGULAR SOXHLET CHARGE RATE AGITATION TEMP. TIME RPI RPI QI OAEXAMPLE (gms) (SCFH/lb) (RPM) (°C.) (HRS) (%) (%) (%) (%)__________________________________________________________________________6 675 2.0 530 400 12 56.9 50.4 43.9 907 675 2.5 530 400 12 -- 44.5 41.5 1008 675 3.0 530 400 12 62.3 55.9 50.2 100__________________________________________________________________________
The comparison of the development of optical anisotropy in the pitch using the low and high agitation rates is illustrated in FIG. 4. The data show that with high agitation and a nitrogen gas rate as low as 2.5 SCHF/lb pitch gave 100% optical anisotropy. As noted above, the present discovery concerns the criticality of the agitation rate in conjunction with the nitrogen gas rate in obtaining an essentially 100% optical anisotropic pitch feed material suitable for carbon fiber production.
Various changes and modifications can be made in the method of this invention without departing from the scope and spirit thereof. Although embodiments of the inventions have been illustrated above, there was no intention to limit the invention thereto. | An improved process for preparing an optically anisotropic pitch which comprises heating a pitch feed material at a temperature within the range of about 350° C. to 450° C. while passing an inert gas therethrough at a rate of at least 2.5 SCFH/lb of pitch feed material and agitating said pitch feed material at a stirrer rate of from about 500 to 600 rpm to obtain an essentially 100% mesophase pitch product suitable for carbon production. | 3 |
FIELD OF INVENTION
This invention relates to telephone handset holders. In particular, this invention relates to a holder for supporting a mobile telephone handset in position for use while driving.
BACKGROUND OF THE INVENTION
Mobile telephones, commonly known as "cellular telephones", have become extremely popular in the past decade. One of the most common uses for mobile telephones is in an automobile, where mobility precludes the use of a hard-wired communications system. The widespread availability and relatively low cost of mobile telephones has all but eliminated the more traditional CB radio as the communications device of choice for automobiles.
One of the disadvantages that this gives rise to, however, is that the user must dedicate one hand to the use of the telephone, which during the operation of an automobile is inconvenient at best, and is often dangerous. So-called "hands free" systems are available to avoid this problem, but these primarily involve speaker and/or microphone extensions which are connected to the telephone and must be mounted within the automobile cabin, the speaker in a position from which it can be heard and the microphone in a position in which it will pick up the driver's voice. As such the microphone will pick up any ambient noise from within the automobile cabin, and the user's privacy is lost if there are other occupants in the automobile. Such systems are also quite expensive, particularly considering that they are merely redundant extensions of features that are already built into the telephone handset.
Holders for telephone handsets generally are known. For example, U.S. Pat. No. 5,008,932 for an Adjustable Phone Handset Shoulder Support and U.S. Pat. No. 4,552,995 for a Portable Cordless Phone Holder both teach handset holders which are adapted to rest on the user's shoulder and support the telephone handset in position for use, ie. adjacent to the user's ear and mouth. However, such holders are relatively cumbersome and bulky, and the use of a shoulder support for supporting the handset can cause muscle strain and fatigue as the user will have a tendency to raise the shoulder or bend the neck to properly position the handset. This to some degree also restricts movement of the user's arm, which is not particularly desirable when the user is driving an automobile. Moreover, in each case the holder is fixed in position on the user's shoulder when in use, and must be completely removed when not in use so as not to unnecessarily obstruct the user's movement or vision while driving.
SUMMARY OF THE INVENTION
The present invention overcomes these disadvantages by providing a telephone handset holder which engages the handset and is provided with means for clipping the holder to the shoulder strap of a seat belt. The handset is thus supported by the shoulder strap, not the user, so that the handset is oriented toward the user's ear and mouth when positioned for use.
In the preferred embodiment the holder is slidably mounted on the shoulder strap, fixed in position by frictional resistance to movement, and can be slid along the shoulder strap to the most comfortable position for use. Moreover, when the handset is not in use, the holder can be slid down the shoulder strap toward lap level for temporary storage, well out of the way of the user's head, without removing the handset from the holder and without detaching the holder from the shoulder strap.
It will be appreciated that the use of the holder of the present invention can increase automobile safety, by freeing the driver's hands during use of a mobile telephone, providing an easy means for stowing the telephone well out of the way when not in use, and even by encouraging the use of the safety belt in an automobile.
The present invention thus provides a holder for a mobile telephone handset comprising handset gripping means for gripping the handset and strap clipping means attached to the handset gripping means for slidably engaging the holder to a shoulder strap of a seat belt in an automobile, whereby the strap clipping means frictionally engages the shoulder strap to retain the holder in a selected position along the shoulder strap.
The present invention further provides a holder for a mobile telephone handset comprising handset gripping means for gripping the handset comprising a pair of opposed resilient gripping arms, strap clipping means for slidably engaging the holder to a shoulder strap of a seat belt in an automobile, comprising at least one clip arm projecting from a clip base attached to the handset gripping means, for frictionally engaging the shoulder strap to retain the holder in a selected position along the shoulder strap, whereby the frictional engagement of the holder to the shoulder strap may be overcome by a user to slide the holder to a selected position along the shoulder strap.
BRIEF DESCRIPTION OF THE DRAWINGS
In drawings which illustrate by way of example only a preferred embodiment of the invention,
FIG. 1 is a perspective view of a preferred embodiment of the telephone handset holder,
FIG. 2 is an end elevation of the telephone handset holder of FIG. 1 showing the handset in phantom lines,
FIG. 3 is an end elevation of the telephone handset holder of FIG. 1 showing the handset being inserted into the holder,
FIG. 4 is an end elevation of the telephone handset holder of FIG. 1 showing the manner of insertion of the shoulder strap into the strap clip, and
FIG. 5 is an end elevation showing the telephone handset holder attached to a shoulder strap in an automobile.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a preferred embodiment of the telephone handset holder 20 of the invention for mounting a mobile telephone handset 10 to the shoulder strap 4 of an automobile. A typical mobile telephone handset 10 has a generally rectangular housing including side walls 12 which may or may not be provided with a recess 14, a rear wall 16, and a front panel 18 which provides a push button dialling pad and appropriate openings to the microphone and speaker (not shown).
The holder 20 is provided with handset gripping means 22, which in the preferred embodiment comprises a pair of opposed resilient gripping arms 24 spaced apart so as to snugly grip the handset 10. The gripping arms 24 project in generally parallel relation from a base portion 30, and each gripping arm 24 terminates in a barb 26 for resisting dislodgement of the handset 10.
The base portion 30 includes a pair of back support surfaces 32 oriented generally orthogonally to the gripping arms 24, which surfaces 32 abut the back 16 of the handset 10 when the handset 10 is fully engaged in the gripping means 22. Thus, the length of each gripping arm 24 is preferably selected so that the barbs 26 lodge into recesses 14 extending longitudinally along the sides 12 of the handset 10, or in the absence of recesses 14, so that the barbs 26 just clear the sides 12 of the handset 10, when the handset 10 is fully engaged in the gripping means 22. Thus, when the handset 10 is engaged in the gripping means 22 as shown in FIG. 2, the barbs 26 retain the handset 10 against the back support surfaces 32.
The base portion 30 includes strap clipping means 40 comprising in the preferred embodiment a clip base 34 oriented at an acute angle relative to the back support surfaces 32. In the embodiment shown the clip base 34 is oriented at approximately 45° relative to the back support surfaces 32, for reasons which will be described below. The clip base 34 is wide enough to accommodate the width of a standard seat belt shoulder strap 4, and in the embodiment shown is attached to the back support surfaces by connecting members 36, 38.
Preferably the holder 20 is extruded, moulded or otherwise formed from a semi-rigid plastic such as PVC or ABS, all components of the holder 20 being thereby integrally connected for strength. Appropriate strengthening ribs and reinforcing braces (not shown) may be formed into the holder 20 as required, which may or may not be necessary depending upon the type of plastic used, the thickness of the plastic and the depth (end to end) of the holder 20. The selected plastic should be strong enough that the gripping arms 24 provide a good grip on the handset 10, but resilient enough so that the gripping arms 24 are able to splay apart slightly to accommodate the handset 10 as it is being inserted into or removed from the holder 20, as illustrated in FIG. 3.
It will be appreciated that the degree of flexure in the gripping arms 24 is increased by the open configuration of the base portion 30, in that the back support surfaces 32 are not directly connected together and can thus spread apart when the gripping arms 24 are urged outwardly. If desired the back support surfaces 32 could be connected together, either by a web of plastic or by integrating the support surfaces 32 into a single back support surface, to increase the rigidity of the gripping arms 24.
In the preferred embodiment the strap clipping means 40 comprises a pair of opposed clip arms 42 which are formed integrally with the holder 20 and project from the clip base 34. The clip arms 42 are each oriented generally parallel to the clip base 34 and are closely spaced therefrom. The clip arms 42 may be provided with enlarged portions 44 which abut or rest very close to the clip base 34 so that, when the clip arms 42 are engaged to a shoulder strap 4, the shoulder strap 4 is squeezed between the enlarged portions 44 and the clip base 34, to provide the necessary frictional resistance to movement.
Thus, the clip arms 42 prevent lateral dislodgement of the holder 20 from the shoulder strap 4, but also provide a transverse frictional engagement against the shoulder strap 4 to retain the holder 20 on the shoulder strap 4 at a level selected by the user. The selected plastic should be such that the clip arms 42 provide a strong grip against the shoulder strap 4, but are resilient enough so that the clip arms 42 are able to flex away from the clip base 34 slightly, to accommodate the shoulder strap 4 as it is being inserted into the clipping means 40 in the manner illustrated in FIG. 4.
It can thus be seen that the frictional force of the clip arms 42 and clip base 34 against the shoulder strap 4 must be sufficient to resist the gravitational force of the handset 10, and any additional downward momentum caused by the motion of the automobile and, at the same time, the frictional resistance to movement of the holder 20 along the shoulder strap 4 should be capable of being overcome fairly easily by the user. Since mobile telephone handsets are typically fairly light, there is a wide range of frictional resistance which will accomplish this and, as such, there are several conventional configurations of clipping means 40 which could be used in place of the opposed clip arms 42 described and illustrated. However, the opposed clip arms 42 are preferred since their opposed orientation prevents lateral dislodgement of the holder 20 from the shoulder strap 4 (which is important in a moving automobile), and the relatively short length of each clip arm 42 will impart significant rigidity that will urge the clip arms 42 against the shoulder strap 4 and frictionally maintain the holder 20 in the selected position along the shoulder strap 4. If necessary, those surfaces of the clip base 34 and/or the clip arms which bear against the shoulder strap 4 can by knurled or mottled or otherwise provided with a rough texture to increase the frictional resistance to movement of the holder 20 along the shoulder strap 4.
In operation, the shoulder strap 4 is inserted into the clipping means in the manner illustrated in FIG. 4, by sliding one edge of the shoulder strap 4 fully between one clip arm 42 and the clip base 34, pinching the sides of the shoulder strap 4 together so that the strap 4 puckers longitudinally, and inserting the other edge of the shoulder strap 4 between the other clip arm 42 and the clip base 34. The strap clipping means 40 should be wide enough that the shoulder strap 4 lays flat against the clip base 34 when fully inserted. The handset 10 is inserted into the handset gripping means 20 in the manner shown in FIG. 3, such that the gripping arms 24 snap into snug engagement against the sides 12 of the handset 10 as the barbs 24 engage the recess 14 or clear the sides 12 of the handset 10.
FIG. 5 illustrates the mobile telephone handset holder of the invention in operation, with the holder 20 positioned at the level of the user's head when the handset 10 is in use. It can be seen that the shoulder strap 4 when worn by the user faces generally forwardly and slightly upwardly; thus the handset gripping means 22 is oriented at an acute angle relative to the clip base 34 so that the handset 10 generally faces the user's head. Minor adjustments in the level of the handset 10 can be made by sliding the holder 20 slightly up or down along the shoulder strap 4. When the handset 10 is not in use, the user simply grasps the handset 10 or the holder 20 and slides the holder 20 down the shoulder strap 4 toward lap level, as shown in phantom in FIG. 5, where the handset 10 is essentially stowed. The user can at any time slide the handset 10 and holder 20 back up along the shoulder strap 4 to head level for further use.
In most cases it is not strictly necessary that the clips 42 bear very strongly against the clip base 34, as the pressure of the shoulder strap 4 against the user's body will generally be sufficient to maintain the holder 20 in position.
When the user leaves the automobile, the handset 10 may be easily disengaged from the holder 20 and taken by the user while leaving the holder 20 clipped to the shoulder strap 4. Alternatively, the entire holder 20 can be easily removed from the shoulder strap 4 for use in another automobile.
Preferred embodiments of the invention having thus been described by way of example, it will be apparent to those skilled in the art that modifications and adaptations may be made without departing from the scope of the invention. For example, there are many other conventional means available for securing the handset 10 to the holder 20, and as noted above there are several conventional configurations of clipping means 40 which could be used in place of the opposed clip arms 42 described and illustrated. The invention is intended to include all such embodiments as fall within the scope of the appended claims. | The present invention provides a telephone handset holder which engages a mobile telephone handset and is provided with means for clipping the holder to the shoulder strap of a seat belt, preferably so that the handset is oriented toward the user's ear when in position for use. In the preferred embodiment the holder is slidably mounted to the shoulder strap, fixed in position by frictional engagement, and can be slid to the most comfortable position for use. When the telephone is not in use the handset can be slid down the shoulder strap to lap level for temporary storage, without removing the handset from the holder and without detaching the holder from the shoulder strap. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a cerebral function-ameliorating agent and more particularly to a cerebral function-ameliorating agent without any substantial fear for side effects.
2. Description of the Prior Art
With recent increasing population of aged persons, there are more and more people suffering from cerebral functional disorders such as cerebral blocking, dementia, etc. Various synthetic medicaments have been clinically offered to these symptoms as cerebral circulation-metabolism ameliorating medicaments, but in the current actual situation various side effects caused by long term dosage due to properties specific to these medicaments have been unavoidable.
As a result of studies on effects of alcohol extract of Crocus sativus L. on memory and learning, the present inventors found that it was effective for the learning behavior of mice in passive avoidance tasks [Nippon Yakugakkai (Society of Pharmaceutical Sciences of Japan), No.133 Annual Conference Lecture Summary, page 35].
SUMMARY OF THE INVENTION
An object of the present invention is to provide a cerebral function-ameliorating agent without any substantial fear for side effects, which is a carotenoid derivative isolated from Crocus sativus L., etc.
According to the present invention, there is provided a cerebral function-ameliorating agent, which comprises a crocetin disaccharide ester, represented by the following general formula: ##STR2## wherein R 1 and R 2 are gentiobiose groups or glucose groups and may be the same or different groups from each other.
DETAILED DESCRIPTION OF THE INVENTION
Crocetin (8,8'-diapocarotenedioic acid, which is a compound with R 1 and R 2 each being a hydrogen atom in the above-mentioned formula) is a carotenoid compound (red crystal) isolated from Crocus sativus L.. In the present invention, digentiobiose ester [crocin], monoglucose monogentiobiose ester or diglucose ester thereof is used as an effective component of the present cerbral function-ameliorating agent, where the esterified gentiobiose is a reducible disaccharide whose two D-glucose molecules are combined together at β1-6.
That is, crocetin is one of several hundred carotenoid pigments contained in plants, and these carotenoid pigments have been actually used as medicaments (β-carotin, etc.), food-coloring agents, antioxidants, etc. and can be deemed to be compounds without any substantial fear for side effects.
The above-mentioned compounds are available in the form of medicaments or foodstuff. In case of medicaments, they are offered in the form of powder, granules, tablets, sugar-coated tablets, capsules, liquids, etc. In case of foodstuff, they are offered in the form of gum, candy, zelly, tableted cake, beverage, etc. In case of medicaments, they can be administered perorally, parenterally, by inhalation, by perrectum, locally, etc. Parenteral administration includes, for example, subcutaneous, intracerebral-lateraventicular, intravenous, intramuscular, intranasal administrations or injections, etc. Administration dose is generally in a range of about 10 to 500 mg/kg body weight for one administration, and usually 1 to 5 administrations are made daily. Exact dose is selected from the above-mentioned range in view of age, body weight and symptom of a patient, administration route, etc.
Their toxicity is low and investigation of their acute toxicity on male Wistar rats by oral administration showed no killing cases even at a dose as much as 3,000 mg/kg (p.o.).
It is known that ethanol induces a memory deficit to animals. As a result of studies of these crocetin disaccharide esters on hippocampal long-term potentiation, which is deemed to be closely related to memory and learning, the present inventors have found that these medicaments are effective for dose-dependently improving the hippocampal long-term potentiation blocking effect of ethanol and thus effective as a cerebral function-ameliorating agent.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing evoked long-term potentiation in control group.
FIG. 2 is a diagram showing long-term potentiation blocking effect of intravenously administered ethanol.
FIG. 3 is a diagram showing an effect of medicament 1 on the long-term potentiation blocking effect of intravenously administered ethanol.
FIG. 4 is a diagram showing an effect of medicament 2 on the long-term potentiation blocking effect of intravenously administered ethanol.
FIG. 5 is a diagram showing an effect of medicament 3 on the long-term potentiation blocking effect of intravenously administered ethanol.
FIG. 6 is a diagram showing the effects of medicaments 1 to 3 on the long-term potentiation blocking effect of intravenously administered ethanol calculating area under curve.
PREFERRED EMBODIMENTS OF THE INVENTION
Example
1) Effects of Medicaments on Rats Hippocampal Long-term Potentiation
Male Wister rats, 8 to 9 weeks old, were anesthetized with urethan-chloralose and an intravenous administration canule was inserted into the rear foot vein and fixed to a cerebral stereotaxic apparatus. Impulses of 0.8 m sec duration were given to the medial perforant path at intervals of 30 seconds and evoked potentials from the granule cell layer of hippocampal dentate gyrus were extracellularly recorded. Stimulus intensity was set to a level which produced a population spike of about 50% of the maximum amplitude. After the evoked potentials became stable, medicaments were administered.
Hippocampal long-term potentiation could be induced only by one application of strong tetanic stimulation of 30 pulses at 60 Hz to the medial perforant path. After the application of strong tetanic stimulation, evoked potentials were recorded for 60 minutes to calculate potentiation percentages to the evoked potential before the application of strong tetanic stimulation.
2) Long-term Potentiation Blocking Effect of Intravenously Administered 30% Ethanol and Effects of the Medicaments According to the Present Invention
20 minutes before the application of tetanic stimulation, the following medicaments 1 to 3 of the present invention, which were each isolated from the pistils of Crocus sativus L. as extracts, were intracerebroventricularly administered, and 5 minutes thereafter 30% ethanol was administered at a dose of 2 ml/kg.
Medicament 1: Crocetin digentiobiose ester
(Administration dose: 51.2 n mol)
Medicament 2: Crocetin monogentiobiose monoglycose ester
(Administration dose: 102.4 n mol)
Medicament 3: Crocetin diglucose ester
(Administration dose: 102.4 n mol)
Effects of the respective medicaments on the long-term potentiation blocking effect of intravenously administered ethanol were determined as spike amplitude and compared several data sets of time course curve of potentiation. Results are shown in FIGS. 3 to 5.
FIG. 1 is a diagram showing evoked long-term potentiation of intracerebroventricular administration of 5 μl of physiological saline and intravenous administration of physiological saline at 2 ml/kg in the control group as time course curves of spike amplitude (potentiation percentages of evoked potentials).
FIG. 2 is a diagram showing long-term potentiation blocking effect of intracerebroventricular administration of 5 μl of physiological saline and intravenous administration of 30% ethanol at 2 ml/kg as time course curve of spike amplitude (potentiation percentages of evoked potentials), where i.c.v. means intracerebroventricular administration and i.v. means intravenous administration.
After the application of tetanic stimulation, area under curve (AUC) was integrally calculated for a duration of 5 min. to 60 min. to dermine a significant difference according to Duncan's multiple range test, where symbols have the following meanings:
** P<0.01 vs. control group (n=6)
# P<0.05
## P<0.01 vs. 30% ethanol alone (n=13)
Medicaments 1 to 3 were intracerebroventricularly administered at the above-mentioned administration doses and 5 minutes thereafter 30% ethanol was intravenously administered at 2 ml/kg. In the diagram of FIG. 6, the intracerebroventricularly administered medicaments and their administration doses (unit: n mol) are shown on the abscissa. | Crocetin disaccharide esters represented by the following general formula: ##STR1## wherein R 1 and R 2 are gentiobiose groups or glucose groups and may be the same or different groups from each other, are effective for dose-dependently improving the hippocampal long-term potentiation blocking effect of ethanol and are used as an effective cerebral function-ameliorating agent. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] U.S. patent application Ser. No. 11,835,899
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] The present invention relates to a system and method for purifying water containing organic compounds, certain inorganic compounds, and microbial contaminants by combining filtration, ultraviolet germicidal irradiation, and photocatalysis in a helical reactor geometry that maximizes (a) photocatalyst surface illumination by UV photons, and (b) contaminant/photocatalyst contact, as well as, (c) providing a quantitative basis for estimating the efficacy of the assembly.
[0005] Some of the earliest published references to titania (titanium dioxide or TiO 2 ) photocatalysts are by Formenti, M., et al., “Heterogeneous Photocatalysis for Oxidation of Paraffins”, Chemical Technology 1, 680-686, 1971 and U.S. Pat. No. 3,781,194 issued Dec. 25, 1973. Since the 1972 discovery, by Fujishima and Honda, of the photocatalytic splitting of water on titanium dioxide electrodes, the science and technology related to heterogeneous photocatalysis in both water and air has been extensively studied and is the subject of numerous patents and scientific publications. Both the physics and chemistry of heterogeneous photocatalysis remain areas of active investigation. Much of the early work of relevance to this patent is summarized in Reference 1, by Okura, et al., including extensive discussion of the self-cleaning properties of irradiated photocatalytic surfaces. Despite investigation of many alternatives, the anatase crystal morphology of titanium dioxide remains the photocatalytically active semi-conductor of economic choice, although many claims of additive enhancements have been and continue to be made. Other, possibly less economic, photocatalytic materials continue to be discovered and investigated, as exemplified by Reference 2.
[0006] Not all water contaminants are treatable by filtration and photocatalysis. Dissolved inorganic salts, in particular, require other chemical and/or physical demineralization processes, e.g., reverse osmosis.
[0007] Photocatalytic water purifier design considerations, impacting performance, include: (a) the intensity and wavelength of irradiation at the illuminated photocatalyst surface, (b) the magnitude of the illuminated photocatalyst surface area, (c) the rate of flow of contaminants past the illuminated photocatalyst surface area, (d) intimate contact of contaminants with the illuminated photocatalyst surface, and (e) the self-cleaning properties of the water/contaminant contacted photocatalyst surface. The “quantum or photocatalytic efficiency” relates to the fraction of light-source photons that are effective in causing photocatalyzed reactions. Considerable effort is currently being expended, in the field of heterogeneous photocatalysis, to enhance the photocatalytic efficiency of anatase titanium dioxide with various catalytic additives (as described in many of the patents cited, e.g., U.S. Pat. Nos. 6,409,928, 6,179,972, and 6,221,259) and to extend the wavelength of photocatalyst-activating irradiation into the visible wavelength range, as described in U.S. Pat. Nos. 7,153,808 and 7,175,911.
[0008] Published designs of photocatalytic reactors for water purification include both unconsolidated/dispersed and immobilized photocatalyst materials:
1. photocatalyst slurry reactors (dispersed photocatalyst particles) 2. fluidized photocatalyst bed reactors (photocatalyst immobilized on substrate particles, beads, or balls) 3. packed bed reactors (photocatalyst immobilized on substrate packing surfaces; honeycombs may be deemed to be a form of “packed bed”) 4. tubular reactors (annular or helical geometry, immobilized surface coatings, including the present patent) 5. catalyst-coated rotating-tube-bundle reactors
[0014] Since photocatalyst illumination is the most important factor, in photocatalytic water purification, access to the photocatalyst surface by photons is critical. In all reactor types, water turbidity should be minimized by pre-filtration. In reactor types 1-3, light penetration depth is impeded by photocatalyst particle light absorption/shadowing and Beer-Lambert absorption. Without induced turbulence, reactors of type 4 (other than the present invention) are most limited by (a) Beer-Lambert absorption, (b) relatively small illuminated photocatalyst surface area, and (c) limited contact between contaminants and illuminated photocatalyst surface. Reactor type 5 overcomes many of the problems of reactor types 1-4, but with considerable complexity (many fast moving parts). Reference 6 verifies the importance of turbulence in achieving contaminant/photocatalyst contact (reactor type 5).
[0015] As discussed below, the prior art includes many water purification systems and methods involving UV light sources and either helical/spiral wound tubing or baffles or guides within the apparati that cause the water stream to spiral about the UV light source. None of the prior art apparati containing helical/spiral tubes have such tubes internally coated with photocatalyst. Without a photocatalytic coating, otherwise transparent tubing walls and windows, in contact with water to be treated, can become fouled (sliming and/or sedimentation), requiring elaborate cleaning mechanisms or processes. Some prior art water purification reactor systems and processes require elevated temperatures and other non-photocatalysts that are not relevant to the current patent.
[0016] A further consideration in the design of an ambient-temperature photocatalytic water purification reactor is the wavelength of the photocatalyst-activating radiation. There is some evidence (Reference 4) that more energetic photons (254 nm) are more effective in photocatalyzing water-borne contaminants than less energetic photons (365 nm). The photon energy in excess of the band-gap energy of the photocatalyst would be expected to add to the kinetic energy of the released electrons and, thereby, contribute to the activation energy of reaction intermediates (i.e., promote reactions). Enhanced photocatalytic activity is in addition to the germicidal benefit of direct ultraviolet germicidal irradiation alone.
[0017] Where the photocatalyst substrate (tubing) material is optically transparent, the tubing wall acts as an elementary waveguide having a reactive inner coated surface. Refraction and reflection (both internal and external) ensure efficient distribution of light photons throughout the length of the helix, until absorption at the internal photocatalytic coating occurs.
[0018] Early work with photocatalyst powder coatings encountered particle size minimization and bond-to-substrate issues. Unconsolidated powder slurries present photocatalyst recovery and recycling problems. Various high temperature coating application techniques have been technically successful but are economically and practically prohibitive for coating the interior surfaces of tubing. Organic binders for powders, such as methylmethacrylate and various organic resins, can not be expected to provide sufficient bond strength to withstand the erosion of fast-flowing water. Titanium oxide films formed by baked inorganic peroxotitanium hydrate sol gels together with a peroxotitanic acid binder have been found to have good substrate-bonding and photocatalytic properties.
[0019] Photocatalyzed reactions of organic compounds are known to be strongly endothermic, such that the photocatalyst-activating energy output of commonly available lamps limits the concentrations of treatable water-borne contaminants to parts-per-million (ppm) or less. The concentrations of most organic water-borne contaminants and pathogens are within this treatable range. However, cycling of contaminated water through a photocatalytic water reactor would progressively reduce higher concentrations of contaminants.
[0020] U.S. Pat. No. 4,798,702 discloses a sterilizer unit for fluid media and process. The sterilizer contains a length of thin-walled corrugated tubing/pipe in the shape of a helix coiled around a germicidal radiation source. The tubing is formed from tough, flexible fluorinated polyalkylene resin which is transparent and resistant to germicidal UV irradiation and is also resistant to buildup of film on the inner surface. No photocatalysis is claimed.
[0021] U.S. Pat. No. 4,956,754 discloses an ultraviolet lamp assembly, including a helical tubing coil enclosing a high intensity germicidal ultraviolet lamp (140 to 390 nm), as in the present invention. A tubular housing is preferably of a highly reflective material, as in the present invention. No photocatalysis is claimed.
[0022] U.S. Pat. No. 5,004,541 discloses an ultraviolet radiation fluid purification system involving both filtration and transparent conduits (tubing) helically wound closely about the UV light. The system exposes the fluid to UV irradiation both before and after filtration (a double helix). This is a bidirectional flow helix; water in adjacent coils flows in opposite directions. It should be noted that a unidirectional coil, of the same length achieves the same UV dosage (same passage over the UV source lamp). The latter patent adds reverse osmosis and deionization units to the treatment process. No photocatalysis is claimed.
[0023] U.S. Pat. No. 5,069,782 discloses fluid purification systems consisting of a unitary housing, longitudinal UV lamp (wavelength of output undisclosed), a pair of helical UV-transparent plastic coils surrounding the lamp, and a longitudinal filter, arranged such that water is exposed to UV energy before and after filtration. The helical coils and UV lamp/bulb are enclosed in a reflective sleeve. The housing is not reflective. No photocatalysis is claimed.
[0024] U.S. Pat. No. 5,069,985 discloses a photocatalytic fluid purification apparatus having helical nontransparent substrate surfaces. Within an annular cylindrical housing, one or more nontransparent photocatalyst-coated substrates are coiled longitudinally and helically around a transparent sleeve enclosing the light source of an “activating wavelength”. Water flow is directed to spiral turbulently about the light source. Beer-Lambert absorption would be expected to reduce illumination of the outer portions of the substrate helix.
[0025] U.S. Pat. No. 5,230,792 discloses an ultraviolet water purification system with variable intensity control such that the UV lamp output intensity is matched to the fluid flow. While not part of the claims, FIG. 1 of the patent shows bidirectional helical coils (of some UV impervious material) surrounding the UV light source (bulb). No photocatalysis is claimed.
[0026] U.S. Pat. No. 5,266,215 discloses a water purification unit which combines germicidal UV irradiation and carbon filtration plus UV irradiation in two sections along the same linear UV light source enclosed in a sleeve. The water to be purified is made to swirl about the source of UV radiation in the first section. An ozone generator is suggested to enhance the biocidal process. UV wavelength is not disclosed.
[0027] U.S. Pat. No. 5,376,281 discloses a water purification system and apparatus that includes a plurality of UV radiators comprised of four sets of water-conducting helical quartz tubes surrounding each UV light source, as well as, a plurality of filtration stages including fine, ultrafine, and micro-filters. A first UV radiator/reactor contains a bed of coarse quartz granules followed by a bed of noble metal. A second UV radiator/reactor contains a bed of noble metal followed by a bed of coarse quartz granules. A third radiator/reactor contains a bed of noble metal followed by a bed of coarse quartz granules. A fourth radiator/reactor contains a bed of coarse quartz granules. Vibration of the quartz granules and exposure to noble metals is stated to destroy microbes. No photocatalysis is claimed.
[0028] U.S. Pat. No. 5,384,032 discloses a water purifying and sterilizing apparatus which includes a box (enclosure) containing three filtering chambers: the first containing resin, the second containing charcoal, and the third containing a UV lamp. Internal baffles cause the water to circulate spirally around the UV lamp. No photocatalysis is claimed.
[0029] U.S. Pat. No. 5,393,419 discloses an ultraviolet lamp assembly for water purification. The apparatus described consists of a cylindrical pressure vessel housing a UV light. The UV lamp assembly is sealed within a transparent sleeve. Internal deflectors and baffles regulate the water flow rate and cause the water to circulate in a helical pattern around the UV lamp. There is an allusion to a filter stage. No photocatalysis is claimed.
[0030] U.S. Pat. No. 5,597,487 discloses an annular water purification system and apparatus comprised of a housing, elongate/linear UV lamp, a sleeve/tube isolating the lamp from the water, and a reflective surface in the annular flow path to UV rays back through the water. No photocatalysis is claimed.
[0031] U.S. Pat. No. 5,785,845 discloses a water purifying system using hydrogen peroxide and/or ozone to enhance the germicidal efficacy of the UV lighting system. A plurality of baffle ridges and grooves produce a rifled spiraling configuration to disrupt laminar flow of contaminated water and bring it in close proximity to the UV source. No photocatalysis is claimed.
[0032] U.S. Pat. No. 5,874,741 discloses an apparatus for germicidal cleansing of water having an ellipsoid chamber containing UV lamps or lasers along the major axis of the ellipsoid. Openings at the ends of the ellipsoid provide entry and exit points for the water. The internal surface of the chamber is formed from a UV-reflective material. A UV-transparent water conduit (tubing) has a helical configuration which spirals about the UV light source through the chamber. No photocatalysis is claimed.
[0033] U.S. Pat. No. 6,153,105 discloses an ice-maker treatment system that disinfects water in an ice-making machine. The system includes at least one UV-transparent tube wound into an approximately spiral shape (helix) and with a UV lamp placed approximately into a center of the spiral shape. No photocatalysis is claimed.
[0034] U.S. Pat. No. 6,162,406 discloses an electrodeless discharge system for ultraviolet water purification consisting of a housing, electronic control circuitry, a low pressure electrodeless discharge lamp with a toroidal discharge, and UV-transparent tubing wrapped in one or more turns around the lamp (helix). No photocatalysis is claimed.
[0035] U.S. Pat. No. 6,379,811 discloses the method of preparation of a yellow transparent jelly (viscous) amorphous type titanium peroxide sol which serves as an excellent binder for titanium dioxide powders and sol gels. These patents further teach that when the titanium peroxide sol is heated at 100 degrees C or more for several hours, the anatase type of titanium oxide sol is obtained. When a substrate is coated with the amorphous type titanium peroxide sol and then dried and heated at 250 to 940 degrees C., an anatase type of titanium dioxide is obtained. This material is similar to the preferred material used to coat the substrate tubing of the present invention,
[0036] U.S. Pat. No. 6,531,035 discloses several apparati and methods for low and high flux photocatalytic pollution control in air and water. This patent provides an interesting classification of catalytic media arrangements into six types. The low-flux photocatalytic media of this invention (operating at temperatures less than 100 deg. C.) are biopolymers such as cotton fabric or flannel cloth supporting titania “molecules” in a photocatalytic “stocking”. The high-flux photocatalytic media of this invention (operating at temperatures in the range 150-400 deg. C.) are support materials like silica, alumina, zeolites, zeolite-like materials, and synthetic aerogel materials, all doped or coated with photo- and thermocatalyst).
[0037] U.S. Pat. No. 6,558,639 discloses an apparatus and method for purifying fluids including contaminants, primarily focused upon air, but mentions washing water in a fifth embodiment. The central concept of the apparatus is a bundle of bundles of linear tubes (pipes) through which the fluids are directed. The inner surfaces of the outer tubes and both inner and outer surfaces of the inner tubes are coated with photocatalyst. The walls of all tubes are transparent to UV irradiation from one or more external lamps oriented in parallel with the tube bundles and fluid flow. Groupings of bundles are also claimed to be possible in series, parallel, or arranged in oblique angles to the direction of fluid passage. There is no discussion of either attenuation of UV intensity at the inner-most tubes or mass transfer/mixing for contaminant-photocatalyst contact. Coating of the tubes is similar to that of the present invention.
[0038] U.S. Pat. No. 6,685,825 discloses a water treatment system combining ozone injection and monitoring apparatus in which the ozone/water mixture is propelled upward in a spiral circling around the quartz sleeve of the UV lamp of the sterilizing unit. There are no claims for photocatalysis.
[0039] U.S. Pat. No. 6,700,128 discloses an apparatus and method for simultaneously germicidally cleansing both air and water involving a germicidal UV chamber in the form of one or more ellipsoid sections. The UV lamp is in the form of a helix around the center line of the chamber. The pitch of the helix may vary along its length so as to concentrate the UV radiation towards the center of the chamber. A transparent conduit for liquids may be positioned in the center of the coils of the UV lamp. This is the reverse geometry to the present invention. There are no claims for photocatalysis.
[0040] U.S. Pat. No. 6,752,971 discloses an ultraviolet water disinfection reactor (flanged insert) for installing in an existing water pipeline. The reactor consists of a plurality of UV lamps within quartz sleeves arranged (in the reactor segment) transversely to the pipeline flow. UV power intensity can be expected to be intense in the immediate vicinity of the lamps, however, flow rate and Beer-Lambert absorption tend to diminish the effective dosage. There are no claims of photocatalysis.
[0041] U.S. Pat. No. 6,875,988 discloses a germicidal lamp and purification system having turbulent flow. A helical grooved contour may be placed directly on the tubular envelope of the UV lamp or on the transparent sleeve enclosing the UV lamp. Such a contour creates turbulence when placed in a fluid flow. The turbulence improves the germicidal efficiency of the UV irradiation. There are no claims of photocatalysis.
[0042] U.S. Pat. No. 6,902,653 discloses an apparatus and method for photocatalytic purification and disinfection of fluids directed through a semitransparent packed bed or an open-cell, three-dimensionally reticulated, fluid permeable, semiconductor (substrate, photocatalyst, and co-catalysts) unit irradiated by UV light in the wavelength range 340-390 nm.
[0043] U.S. Pat. No. 6,932,903 discloses an ultraviolet-and-ozone disinfection apparatus having improvement on disinfection effect. The apparatus includes a ozone generating UV lamp within a quartz sleeve with the annulus filled with air such that ozone is generated in the annulus. The ozone is drawn into the water stream by a venturi. The combined ozone/water stream then circulates around the quartz sleeve through a UV-transparent tubing coil (helix). There are no claims of photocatalysis.
[0044] U.S. Pat. No. 6,932,947 discloses a fluid purification and disinfection device, which includes a housing, UV lamp, and a photocatalytic surface consisting of either a spiral-shaped metal plate or a metal mesh coated on both sides with titanium dioxide and installed around the UV lamp.
[0045] U.S. Pat. No. 6,946,651 discloses a method and apparatus for water purification that involves a tubing coil (helix) enclosing one or more UV lamps, as in the present invention. However, There are no claims of photocatalysis.
[0046] U.S. Pat. No. 7,008,473 discloses a system and process for photocatalytic treatment of contaminated air involving an aqueous phase. The system is primarily targeted towards decontaminating air streams (gas scrubber tower) using an aqueous photocatalytic slurry. Details of UV wavelength and photocatalyst surface illumination effectiveness are not provided.
[0047] U.S. Pat. No. 7,230,255 discloses an annular photocatalytic sterilizer in which water is directed through an annulus containing a photocatalyst-coated “carrier” that is illuminated by a UV lamp (wavelength undisclosed) from the inside. The photocatalyst carrier comprises a spherical, cylindrical, spring-shaped or tube-shaped net made of silica gel, silica, alumina, zeolite, stainless steel, copper, nickel, silver, aluminum, and silver-plated metals.
[0048] U.S. Pat. App. No. 20050016907 discloses a electro-optical water sterilizer that directs the water stream in a spiral course (“spiral pipeline”) about a quartz sleeve (“bushing”) enclosing a germicidal UV light source (253.7 nm). The word “spiral” describes the flow pattern of the water and not a tubular helix. The germicidal effect of this sterilizer is very similar to the present invention. No photocatalysis is claimed in this application.
[0049] U.S. Pat. App. No. 20060019104 discloses a process for the production of a photocatalytically active coated glass. This application also presents the coating durability results of standard abrasion and humidity cycling tests. Thin coats were found to have good durability.
[0050] U.S. Pat. App. No. 20060231470 discloses a photocatalytic water treatment apparatus comprised of a plurality of pairs of stacked, photocatalyst-coated disks and supports which form a cylindrical cartridge with a cylindrical open interior in which a linear UV light source is positioned. The UV light source is a tubular element extending the length of the treatment cartridge. Each disk has a pattern of alternating concentric ribs and grooves that complement the pattern on the opposing disk face to define a flow chamber having a series of concentric flow channels (labyrinthine), such that the water to be treated follows a tortuous path and contacts the full length of each flow channel. The disks are claimed to be made of transparent UV-resistant polymethylmethacrylate plastic, which suggests that the UV wavelength is not germicidal, since such plastic is neither transparent nor resistant to germicidal ultraviolet radiation. There is no discussion of turbulent flow (mass transfer), although that is to be expected from the flow channel configuration.
[0051] U.S. Pat. App. No. 20070020158 discloses a photocatalyst water treating apparatus combining a filtration unit, a photocatalytic processing unit, and an electrolysis unit for removing inorganic and organic contaminants from water without using chemicals. The UV light source can emit radiation ranging from 180 to 400 nm. The UV lamps and planar photocatalytic elements are arranged such that the lamps irradiate both sides of each photocatalytic element.
[0052] U.S. Pat. App. No. 20070095647 discloses a method and apparatus for producing reactive oxidizing species via photocatalytic reactions under UV light (in the wavelength ranges 182-187 nm and 250-255 nm) in humid air. The patent apparently contemplates using polyvinyl chloride as a binder to fix the photocatalyst powder to a substrate, which is then exposed to the UV light. Such short wavelength UV radiation should be expected to degrade the PVC over time. Although the patent uses the words “water purification”, there is little descriptive detail that would enable a practitioner, skilled in the art, to apply the method or apparatus to water purification.
[0053] U.S. Pat. App. No. 20070125713 discloses a water purifier with UV and an adsorbent media list that includes titanium dioxide. The application discusses adsorbent surface modification which includes additional coatings which may be applied to adsorbent media and which may increase the catalytic activity. No specific mention of photocatalysis is made. The application states, “light sources suitable for this invention may radiate in a range from about 200 nm to over 350 nm, preferably in a narrow band around 265 nm”, the lower range of which is germicidal.
[0054] U.S. Pat. App. No. 20070245702 discloses porous honeycomb structures and manufacturing methods for use in air and water purifiers. The patent application describes many manufacturing routes with incorporation of fine catalytic metal and photocatalyst particles, as well as photocatalytic test results in both air and water using a 4 W black light source.
[0055] WO/2006/043283 discloses an integrated portable water purifier incorporating a UV lamp for microbiological treatment, but without photocatalysis.
[0056] WO/2007/010549 discloses a household reverse osmosis based drinking water purifier that incorporates ultra-filtration and/or UV treatment, but without photocatalysis.
[0057] WO/2007/026811 discloses a water purification device that floats at the water surface in a containment tank. A photocatalyst-coated, translucent, and water permeable mass illuminated by UV irradiation provides the photocatalytic purification of contacted water. Mass transfer of water to the photocatalyst surface is by “forced convection” by a convection device.
BRIEF SUMMARY OF THE INVENTION
[0058] The principal objective of the present invention is to introduce a helical system reactor geometry that provides efficient water purification by combining (a) filtration, (b) a large, efficiently-illuminated photocatalytic surface area, (c) a short UV light penetration distance (less than or equal to the tubing inside diameter), and (d) intimate surface contact between water/contaminant and the illuminated photocatalyst surface through flow turbulence induced by the curvature of the tubing helix.
[0059] Secondary objectives of the present invention are to provide formulae that permit quantified estimation of (a) the ultraviolet germicidal irradiation dosage delivered by the system, (b) the available photocatalyst substrate surface, and (c) the applied photocatalyst coating density (g/cm 2 ) on that substrate surface. The germicidal dosages and photocatalyst coating densities are proxies for the photocatalytic efficacy of the invention, in the absence of simple estimation formulae.
[0060] The major elements of the water purification system of the present invention are a filter, motor, pump, and one or more photocatalytic units (arranged in series or parallel), each consisting of an annular arrangement of three components: (a) an internally UV-reflective outer housing that encloses (b) a tubing coil (helix) concentrically/coaxially further enclosing (c) a UV light source illuminating the entire inside area and volume of the helix.
[0061] The photocatalyst substrate (tubing) material is UV-transparent such that the tubing wall acts as an elementary waveguide having a reactive inner (coated) surface. Refraction and reflection (both internal and external) ensure efficient distribution of UV light photons throughout the length of the helix, until absorption at the photocatalytic coating occurs. Such optical properties of light conducting materials are discussed, at length, in U.S. Pat. Nos. 5,875,384 and 6,051,194, with respect to fiber optic cable reactors.
BRIEF DESCRIPTION OF THE DRAWINGS
[0062] The various features of the present invention may be more fully understood with reference to the following description and the accompanying drawings in which:
[0063] FIG. 1 is a schematic representation of one embodiment of an assembled photocatalytic unit (the photocatalytic reactor), including water flow and the major components of a complete system.
[0064] FIG. 2 is a schematic representation of a water purification system illustrating a series combination of photocatalytic units.
[0065] FIG. 3 is a schematic representation of a water purification system illustrating a parallel combination of photocatalytic units.
[0066] FIG. 4 is the basis for the development of EQUATION 1, adapted for notational reference, from FIG. 3 in U.S. patent application Ser. No. 11,835,899
DETAILED DESCRIPTION OF THE INVENTION
[0067] FIG. 1 is an illustrative schematic diagram of one embodiment of a water purifier system and assembly with a photocatalytic unit according to the present invention. The photocatalytic unit, 1 , generally includes the housing (top, 2 , sides, 3 , light source mounting plate, 4 , a photocatalyst-activating light source, 5 , a light source power supply, 6 , a tubing coil (helix), 7 , contaminated water inlet connections, 8 , clean water outlet connections, 9 , water motive means (e.g., gravity or pump and motor), 10 , filtration unit, 11 , electronic controls, 12 , as well as water flow.
[0068] What are not shown in FIG. 1 are the helix stabilizing brackets (within the housing) and details of the water hose/pipe connections, 8 and 9 , to the photocatalytic unit. Similarly, details of valves, fittings, controls, and the inter-connections between photocatalytic units are not shown in FIG. 2 , as well, details of the inlet (distribution) manifold, outlet (collection) manifold, and associated inter-connections are not shown in FIG. 3 .
Ultraviolet Germicidal Irradiation
[0069] To be germicidal, the wavelength of the UV radiation must be sufficiently short (energetic) to break chemical bonds or, at least, denature the DNA or proteins of microbes. This is generally accepted to be in the UV-V and UV-C ranges of the electromagnetic spectrum. While it may not be intuitive, given the quite different geometries, the “average” ultraviolet germicidal irradiation dosage (energy per unit area irradiated) within the photocatalytic unit tubing coil (helix) may be estimated by similar formulae developed for the longitudinal “light-in-pipe” dosage for a steady-state flow of air, as derived in the U.S. patent application Ser. No. 11,835,899, but adjusted for Beer-Lambert absorption in a UV-absorbing medium (water and contents) with an “extinction coefficient, ε. The helix, 7, now substitutes for the pipe, 20 , in length and the fluid flow, F (cubic feet per minute or “cfm”), maintains the same definition (except for units changes from air to liquid measures, say to US gallons per minute or “gpm”). The light source, 19 , remains on the helix axis. However, the radius, R, of a “hypothetical pipe”, flow-equivalent to the helical tubing coil now requires additional calculation, as well as, the average optical path length, P, for the fluid within the helical tubing coil. Knowledge of both ε and P permit an estimate of how much the UV intensity is diminished by passing through the absorbing fluid to the photocatalyst surface on the far side of the tube.
[0070] The average optical path length within the tubing is the average length of all chords defined by rays from any point at the light source intersecting the cross-section circle of the tubing, all in the same plane, where each chord length is defined by:
[0000] Chord(θ)=2*sqrt{ r 2 −[r *cos(θ)−sqrt( C 2 −r 2 )*sin(θ)] 2 }, and
[0000] where, r=radius of the tubing.
C=length of the ray to the center of the tubing. θ=the angle between the ray intersecting the tubing and the ray tangent to the tubing, such that θ max =arcsin(r/C), which is the angle between the ray tangent to the tubing circle and the ray through the tubing cross-section circle center, defining the domain of θ as 0≦θ≦θ max .
[0073] Now the average optical path length, P, (of rays intersecting the tubing) is given by
[0000] P =[∫Chord(θ) dθ]/θ max , integrating between θ=0 and θ=θ max .
[0074] The average optical path length, in the example below, is 0.7846 cm for a 1.00 cm diameter tubing. The result is not sensitive to the length of rays for C much greater than r. As expected, the average optical path length is less than the diameter of the tubing, i.e., P<2r.
[0075] With reference to FIG. 4 , if the inlet end of the light source is considered to be at the origin (zero) of the x-axis, then −B (negative B) is the x-coordinate of the inlet end of the helix, L is the x-coordinate of the outlet end of the light source, and L+E defines the x-coordinate of the outlet end of the helix. K is a “hypothetical” photon-accumulating surface moving through the radiation field of the light source at the same linear velocity as the water through the flow-equivalent pipe (not the velocity within the tubing). It is the radius of K, i.e., R, that must be calculated so that the transit time, t, of K through the pipe is the same as the transit time through the helix. The transit time for the water is calculated as the internal volume of the helix, V, divided by the flow rate, F, of the water, i.e., V/F. Therefore, the linear velocity of K, i.e., F/K, is given by the length of the helix/pipe divided by the transit time, (B+L+E)/(V/F) or
[0000] F *( B+L+E )/ V=F/K, ( F divides out from both sides of the equation).
[0076] Solving the above equation for K yields
[0000]
K
=
V
/
(
B
+
L
+
E
)
=
π
R
2
,
(
round
pipe
)
.
[0077] Therefore,
[0000] R =sqrt( V /(π*( B+L+E ))
UV Energy Dosage
[0078] Because the volumes of liquid water flow are so much less than the volumes of air flow (1 cfm=7.480519 gpm, US liquid), the residence time of water in the radiation field of a UV light source can be much higher in water than in air, such that the UV energy dosages can be correspondingly higher. If the steady-state water flow rate is F (in cubic feet per minute), the average linear velocity of K is F/K (feet per minute, where K is measured in square feet). The transit time for K to traverse the helix/pipe, i.e., K to travel from −B to L+E along the x-axis, is (B+L+E)*K/F. Therefore, the cumulative UV dosage (watt-sec./cm 2 or joule/cm 2 ), CD, delivered by the UV light source and received by area K traversing the helix/pipe is the sum of three parts: the two single-sided end contributions, CD B and CD E , and the two-sided (both sides of K) contribution at the bulb, CD L , such that
[0000]
CD
o
=
CD
B
+
CD
L
+
CD
E
,
before
Beer
-
Lambert
law
adjustment
and
CD
=
CD
o
-
ɛ
P
,
after
Beer
-
Lambert
law
adjustment
where
CD
B
=
(
W
/
(
2
*
F
*
L
)
)
*
{
B
*
L
+
0.5
*
(
B
*
[
B
2
+
R
2
]
1
/
2
+
L
*
[
L
2
+
R
2
]
1
/
2
-
(
L
+
B
)
*
[
(
L
+
B
)
2
+
R
2
]
1
/
2
+
R
2
*
ln
{
(
R
*
(
L
+
[
L
2
+
R
2
]
1
/
2
)
/
(
(
[
B
2
+
R
2
]
1
/
2
-
B
)
*
(
L
+
B
+
[
(
L
+
B
)
2
+
R
2
]
1
/
2
)
)
)
}
)
CD
L
=
W
*
L
/
F
and
CD
E
=
(
W
/
(
2
*
F
*
L
)
)
*
{
E
*
L
+
0.5
*
(
E
*
[
E
2
+
R
2
]
1
/
2
+
L
*
[
L
2
+
R
2
]
1
/
2
-
(
L
+
E
)
*
[
(
L
+
E
)
2
+
R
2
]
1
/
2
+
R
2
*
ln
{
(
R
*
(
L
+
[
L
2
+
R
2
]
1
/
2
)
/
(
(
[
E
2
+
R
2
]
1
/
2
-
E
)
*
(
L
+
E
+
[
(
L
+
E
)
2
+
R
2
]
1
/
2
)
)
)
}
)
EQUATION
1
[0079] These formulae assume no internal reflection. Within the length of the bulb (z=0 to z=L), the dosage, CD L , involves only W, L, and F, with no explicit dependence upon K or R (integrals involving R cancel). While this result is somewhat counter-intuitive, it can be understood by the linear velocity of K as F/K, such that, for example, when K is doubled, the linear velocity of K is halved so the dosage remains the same. When B and E are zero, CD B and CD E are also zero, respectively.
[0000]
TABLE A
Illustrative Cumulative UVGI Dosage (CD) Formula Results*
UV-C Bulb Rating (Watts):
18 W
36 W
60 W HO
Number of Bulbs:
1
1
1
UV-C Output: %
30.8%
30.8%
40.0%
UV-C Watts, W
5.5
11.1
24.0
Envelope Length, L (Inches):
7.5
15.0
15.0
Helix/Pipe Parameters:
Length, B + L + E (Inches):
10.0
17.5
17.5
Distance before Bulb, B (Inches):
1.25
1.25
1.25
Distance after Bulb, E (Inches):
1.25
1.25
1.25
Helix Radius (I.D., Inches):
3.0
3.0
3.0
Tubing Diameter (I.D., Inches):
0.3937
0.3937
0.3937
Average Optical Path Length, P (cm)
0.7820
0.7820
0.7820
Equivalent-Flow Pipe Radius, R (In.):
1.3074
1.3074
1.3074
Water Flow Rate (1) , F (US gpm):
2.0
4.0
2.0
4.0
2.0
4.0
Coefficient of Extinction (2) , ε (cm −1 )
0.2
0.2
0.2
UVGI Dosage, CD (μwatt-sec/cm 2 ):
CD B + CD E
14,058
7,030
14,990
7,496
32,446
16,224
CD L
837,002
418,501
3,348,007
1,674,003
7,246,768
3,623,384
Photocatalytic Unit (CD o ):
851,060
425,530
3,362,997
1,681,498
7,279,214
3,639,607
Adjusted for B-L Law (3) (CD)
727,463
363,731
2,874,597
1,437,298
6,222,071
3,111,036
*Note:
(1) 1.0 gpm (US liquid) = 0.133680556 cfm.
(2) The coefficient of extinction, ε, for 253.7 nm UV light in pure water is 0.007 cm −1 , in tap water it is 0.1 cm −1 , and in average US waste-water treatment plant discharge water it is 0.3 cm −1 (References 7 and 8).
(3) CD = CD o e −εP
[0080] The results in TABLE A are self-consistent to the extent that doubling the water flow rate halves the UV dosage. Furthermore, a longer UV bulb extends the residency time in the irradiation field of the UV light source and, hence, the greater UV dosage calculated for one long 36 W bulb and one long 60 W high output bulb compared with one short 18 W bulb. Similarly, the corresponding results for the 36 W bulb are about four times that of the 18 W bulb at twice the power and twice the length. These results also imply consistent units conversions (imperial units to metric units and vice versa). The dosage units are W-sec/cm 2 (or J/cm 2 ), which must be multiplied by 1,000,000 to convert to the usual “micro” units μW-sec/cm 2 or μJ/cm 2 , as commonly used in the literature. Ninety percent (90% or “one log”) of many water-borne species of molds, bacteria, and viruses are killed or “deactivated” at dosages well under 100,000 μW-sec/cm 2 .
[0081] The massive dosages, indicated by TABLE A, virtually assure the destruction of any biological pathogens, even (a) without the additional benefit of photocatalysis that also destroys microbes and contaminating compounds not perturbed by germicidal irradiation, (b) after attenuation of the UV intensity due to Beer-Lambert law adsorption, and (c) after shadowing by the “front side” photocatalyst coating.
Photocatalyst Surface Area and Coating Density
[0082] The photocatalyst-coatable tubing coil interior surface area, A, is given by the tubing inside circumference times the length, L:
[0000]
A
=
2
π
r
×
L
cm
2
=
π
D
×
L
cm
2
,
where
D
=
2
r
is
the
inside
tubing
diameter
in
cm
.
EQUATION
2
[0000] For a helix of N=32 turns of 0.5 inch I.D. tubing, where D is 6.0 inches, L˜=N×πD. Therefore, A˜=N*(πD) 2 =11,370 in. 2 or 73,353 cm 2 .
[0083] For a tubing coil (helix) weighing S W when freshly coated with wet sol gel solution of known concentration C and density ρ (e.g., g/ml of anatase TiO 2 ) and weighing S D after drying (before baking), the weight of retained dry photocatalyst coating, PC, may be calculated as:
[0000]
PC
=
(
S
W
-
S
D
)
*
C
/
ρ
grams
,
or
=
C
*
v
,
where
v
(
ml
)
is
the
volume
of
sol
gel
retained
by
the
tubing
coil
and
the
coating
density
per
unit
area
of
substrate
surface
is
Coating
Density
=
PC
/
A
,
g
/
cm
2
.
EQUATION
3
Photocatalyst Coating Thickness and Effective Area
[0084] If the tubing coil of the above example retained 80 ml of 0.85% titanium dioxide sol gel also containing peroxotitanic acid binder with a combined solution density of 1.013 g/ml (0.0086 g/ml anatase sol gel and 0.0040 g/ml peroxotitanic acid binder that converts to anatase on baking). The retained sol gel weight implies approximately 1.04 g of TiO 2 (formula weight of 79.87 amu or g/mol) or 1.30×10 −2 mols. Therefore, the formula weight units (mols) per square centimeter are 1.30×10 −2 /73, 353=1.77×10 −5 mols/cm 2 . The unit cell dimensions of nanocrystalline anatase (see Weirich, Reference 9) are 3.872×3.872×9.616 cubic angstroms=0.14417 cubic nm or 0.03604 nm 3 per TiO 2 unit (four TiO 2 units per anatase unit cell). Therefore, a densely packed “spherical” 10 nm diameter particle would contain approximately 14,528 TiO 2 formula units. Furthermore, given the Avogadro Number of formula units per mol (i.e., 6.022045×10 23 ), the number of mols/cm 2 implies 1.77×10 −5 ×6.022045×10 23 /14,528=7.34×10 14 of 10 nm particles/cm 2 . Assuming hexagonal closest packing of spheres, a single layer of 10 nm particles would have an areal packing density of approximately 12×0.5×5×10 nm 2 =300 nm 2 per 3 particles or 100 nm 2 per each 10 nm diameter particle. Each square cm of tubing surface would then accommodate 1/(100×10 −14 cm 2 per particle) particles in a single layer or 1×10 12 particles per cm 2 . This is less than the above calculated 7.34×10 14 particles/cm 2 applied. This result implies a complete surface coating with no gaps between 10 nm particles or an average “mono-layer” particle size of more than 10 nm diameter. The greater apparent coverage than calculated for surface density of “compact” 10 nm particles suggests a higher degree of agglomeration.
[0085] A mono-layer of three-dimensional close-packed spheres (of uniform diameter) on a two-dimensional planar surface would have a total sphere surface area to plane surface area ratio of 2π/√3=2.094, independent of sphere diameter. Therefore, an estimate of photocatalyst area on a uniformly covered (no gaps) substrate surface is 2.094 times the substrate surface area. In the above tubing example, this implies a photocatalyst surface area of approximately 2.094×70.5×10 3 =148×10 3 cm 2 per gram of photocatalyst, further enhanced by the distribution of photocatalyst particle sizes and surface roughness. While not all of this photocatalyst surface is accessible to UV photons, errors of over-estimation and under-estimation are expected to approximately cancel each other.
[0086] While the foregoing may emphasize the preferred embodiments of the present invention, for illustrative purposes, other and further embodiments may be devised without limiting or departing from the spirit and scope of the present invention, as determined by the following claims. | The invention provides a water purification system and method for combining ultraviolet germicidal irradiation and photocatalysis in a helical reactor geometry that maximizes both the photocatalytic efficiency and the germicidal dosage of the ultraviolet irradiation in deactivation of microbes and the destruction of contaminant organic compounds. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation in part of U.S. patent application Ser. No. 13/860,934, entitled “Fabrication of High Efficiency, High Quality, Large Area Diffractive Waveplates and Arrays”, filed Apr. 11, 2013 which is, in turn, a continuation of U.S. patent application Ser. No. 12/662,525, entitled “Fabrication of High Efficiency, High Quality, Large Area Diffractive Waveplates and Arrays”, and filed Apr. 21, 2010.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This invention was made with Government support under Contract No. W911QY-07-C-0032.
RIGHTS OF THE GOVERNMENT
[0003] The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.
FIELD OF THE INVENTION
[0004] This invention relates to fabrication of one- or two-dimensional diffractive waveplates and their arrays, those waveplates including “cycloidal” diffractive waveplates (DWs) or polarization gratings (PGs) with optical axis modulation along a single axis of a Cartesian coordinate system, axial waveplates, vortex waveplates, or q-plates with optical axis modulation in two dimensions, as well as including waveplates with essentially non-linear and aperiodic modulation of optical axis orientation.
BACKGROUND OF THE INVENTION
[0005] Polarization recording of holograms and related “polarization gratings” were conceived in 1970's as a method for recording and reconstructing the vector field of light. A light-sensitive material that acquired birefringence under the action of polarized light was suggested in the first studies (Sh. D. Kakichashvili, “Method for phase polarization recording of holograms,” Sov. J. Quantum. Electron. 4, 795, 1974). Examples of such photoanisotropic media included colored alkaly halid crystals regarded particularly promising due to reversibility of the recording process consisting in optically altering the orientation of anisotropic color centers in the crystal. A medium possessing with photoinduced birefringence was used for polarization sensitive optical storage by Kawano et al. as disclosed in US Patent application US 2001/0002895.
[0006] A grating characterized only by spatial variations in the orientation of the induced optics axis can be obtained when the photoanisotropic medium is exposed to a constant intensity, rectilinear light vibrations, with spatially varying orientation, obtained from superposition of two orthogonal circularly polarized waves propagating in slightly different directions (M. Attia, et al., “Anisotropic gratings recorded from two circularly polarized coherent waves,” Opt. Commun. 47, 85, 1983). The use of Methyl Red azobenzene dye in a polymer layer allowed to claim that photochemical processes in such material systems would enable obtaining 100% diffraction efficiency even in “thin” gratings (T. Todorov, et al., “High-sensitivity material with reversible photo-induced anisotropy,” Opt. Commun. 47, 123, 1983). Highly stable polarization gratings with orthogonal circular polarized beams are obtained in thin solid crystalline Langmuir-Blodgett films composed of amphiphilic azo-dye molecules showing that “100% efficiency may be achieved for samples less than 1 μm thick” (G. Cipparrone, et al., “Permanent polarization gratings in photosensitive langmuir-blodget films,” Appl. Phys. Lett. 77, 2106, 2000).
[0007] A material possesing birefringence that is not influenced by light is an alternative to the photoanisotropic materials that are typically capable of only small induced birefringence (L. Nikolova et al., “Diffraction efficiency and selectivity of polarization holographic recording,” Optica Acta 31, 579, 1984). The orientation of such a material, a liquid crystal (LC), can be controlled with the aid of “command surfaces” due to exposure of the substrate carrying the command layer to light beams (K. Ichirnura, et al., “Reversible Change in Alignment Mode of Nematic Liquid Crystals Regulated Photochemically by Command Surfaces Modified with an Azobenzene Monolayer,” Langmuir 4, 1214, 1988). Further a “mechanism for liquid-crystal alignment that uses polarized laser light” was revealed (W. M. Gibbons, et al., “Surface-mediated alignment of nematic liquid crystals with polarized laser light,” Nature 351, 49, 1991; W. M. Gibbons, et al., “Optically controlled alignment of liquid crystals: devices and applications,” Mol. Cryst. Liquid. Cryst., 251, 191, 1994). Due to localization of dye near the interface, the exposure can be performed in the absence of LC, and the LC is aligned with high spatial and angular resolution (potentially, submicron) after filling the cell (W. M. Gibbons, et al., “Optically generated liquid crystal gratings,” Appl. Phys. Lett. 65, 2542, 1994). Variety of photoalignment materials are developed for achieving high-resolution patterns and obtaining variation of molecular alignment within individual pixels (M. Schadt, et al., “Optical patterning of multi-domain liquid-crystal displays with wide viewing angles,” Nature 381, 212, 1996).
[0008] A critically important issue for producing LC orientation patterns at high spatial frequencies is their mechanical stability. Particularly, the cycloidal orientation of LCs obtained due to the orienting effect of boundaries is stable only when a specific condition between the material parameters, the cell thickness, and the period of LC orientation modulation is fulfilled (H. Sarkissian et al., “Periodically Aligned Liquid Crystal: Potential application for projection displays,” Storming Media Report, A000824, 2004; H. Sarkissian, et al., “Periodically aligned liquid crystal: potential application for projection displays and stability of LC configuration,” Optics in the Southeast 2003 , Orlando, Fla.; Conference Program, PSE 02. and H. Sarkissian, et al., “Potential application of periodically aligned liquid crystal cell for projection displays,” Proc. of CLEO/QELS Baltimore Md., poster JThE12, 2005; B. Ya. Zeldovich, N. V. Tabirian, “Devices for displaying visual information,” Disclosure, School of Optics/CREOL, July 2000). Suggesting fabrication of cycloidal polarization gratings using the photoalignment technique with overlapping right and left circularly polarized beams, the publications by Sarkissian, Zeldovich and Tabirian cited above are credited for having theoretically proven polarization gratings can be 100% efficient and can be used as a diffractive grating for projection displays (C. Provenzano, et al., “Highly efficient liquid crystal based diffraction grating induced by polarization holograms at the aligning surfaces,” Appl. Phys. Lett., 89, 121105, 2006; M. J. Escuti et al., “A polarization-independent liquid crystal spatial-light-modulator,” Proc. SPIE 6332, 63320M, 2006).
[0009] LCs with spatially modulated orientation patterns produced using the photoalignment tecbnqiue are known in the prior art (W. M. Gibbons, et al., “Surface-mediated alignment of nematic liquid crystals with polarized laser light,” Nature 351, 49, 1991; C. M. Titus et al., “Efficient, polarization-independent, reflective liquid crystal phase grating,” Appl. Phys. Lett. 71, 2239, 1997; J. Chen, et al., “An electro-optically controlled liquid crystal diffraction grating, Appl. Phys. Lett. 67, 2588, 1995; B. J. Kim, et al., “Unusual characteristics of diffraction gratings in a liquid crystal cell,” Adv. Materials 14, 983, 2002; R.-P. Pan, et al., “Surface topography and alignment effects in UV-modified polyimide films with micron size patterns,” Chinese J. of Physics 41, 177, 2003; A. Y.-G. Fuh, et al., “Dynamic studies of holographic gratings in dye-doped liquid-crystal films,” Opt. Lett. 26, 1767, 2001; C.-J. Yu, et al., “Polarization grating of photoaligned liquid crystals with oppositely twisted domain structures,” Mol. Cryst. Liq. Cryst. 433, 175, 2005; G. Crawford, et al., “Liquid-crystal diffraction gratings using polarization holography alignment techniques,” J. of Appl. Phys. 98, 123102, 2005; Crawford et al., U.S. Pat. No. 7,196,758).
[0010] LC polymers were widely used as well (M. Schadt, et al. “Photo-Induced Alignment and Patterning of Hybrid Liquid Crystalline Polymer Films 011 Single Substrates,” Jpn. J. Appl. Phys. 34, L764 1995; M. Schadt, et al. “Photo-Generation of Linearly Polymerized Liquid Crystal Aligning Layers Comprising Novel, Integrated Optically Patterned Retarders and Color Filters,” Jpn. J. Appl. Phys. 34, 3240, 1995; Escutti et al, US Patent Application US2008/0278675). Photo-aligned anisotropic thin films can be applied to rigid or flexible substrates, which may be flat or curved and/or generate patterned retarders with continuous or periodical inplane variation of the optical axis (H. Seiberle, et al., “Photo-aligned anisotropic optical thin films,” SID 03 Digest, 1162, 2003).
[0011] The CDWs wherein the optical axis of the material is periodically rotating in the plane of the waveplate along one axis of a Cartesian coordinate system are among the most interesting one-dimensional structures used for applications such as displays, beam steering systems, spectroscopy etc. These are known also as optical axis gratings, and polarization gratings (PGs) (S. R. Nersisyan, et al., “Optical Axis Gratings in Liquid Crystals and their use for Polarization insensitive optical switching,” J. Nonlinear Opt. Phys. & Mat. 18, 1, 2009). Some interesting for applications two-dimensional orientation patterns possess with axial symmetry (N. V. Tabiryan, et al., “The Promise of Diffractive Waveplates,” Optics and Photonics News 21, 41, 2010; L. Marucci, US Patent Application 2009/0141216; Shemo et al., US Patent Application 2010/0066929) and may have nonlinear dependence on coordinates.
[0012] It is important to introduce a clear distinction between polarization holograms, polarization gratings and diffractive waveplates as referenced to in further discussion. Polarization holograms are recorded with overlapping orthogonal polarized reference and pump beams in photoresponsive anisotropic materials. It is generally implied that the reference beam is spatially modulated and carries information.
[0013] The term “polarization grating” usually refers to a polarization hologram recorded with two orthogonal polarized beams that are not spatially modulated to carry information. Typically, these beams are equal in intensity and none can be singled out as reference.
[0014] Waveplates are thin anisotropic films with special conditions on orientation of optical axis and phase retardation L(n e −n 0 )=λ/2, where n e and n 0 are the principal values of refractive indices of the material, and L is the thickness, The optical axis orientation is spatially modulated in DWs. Particularly, CDWs present rotation of the optical axis of the material at a constant rate along a single axis of a Cartesian coordinate system. To the degree CDWs can be produced using holography techniques, they can be regarded as a subclass of polarization holograph y or polarization gratings.
[0015] Axial DWs (ADWs or vortx waveplates) are the polar analog of CDWs and cannot be obtained with polarization holography techniques. As mentioned above, DWs can possess with more complex optical axis modulation patterns, and they are distinguished with a specific phase retardation condition.
[0016] Thus, in the prior art, optical axis modulation patterns of anisotropic material systems were demonstrated, including in LCs and LC polymers, due to modulation of boundary alignment conditions, and it was shown that such boundary conditions can be achieved by a number of ways, including using photoaligning materials, orthogonal circular polarized beams, microrubbing, and substrate rotation (Fünfshilling et al., U.S. Pat. No. 5,903,330; B. Wen, et al., “Nematic liquid-crystal polarization gratings by modification of surface alignment,” Appl. Opt. 41, 1246, 2002; S. C. McEldowney et al., “Creating vortex retarders using photoaligned LC polymers,” Opt. Lett., Vol. 33, 134, 2008). LC optical components with orientation pattern created by exposure of an alignment layer to a linear polarized light through a mask, by scanning a linear polarized light beam in a pattern, or creating a pattern using an interference of coherent beams is disclosed in the U.S. Pat. No. 5,032,009 to Gibbons, et al. Also, in the prior art, “Optically controlled planar orientation of liquid crystal molecules with polarized light is used to make phase gratings in liquid crystal media” (W. M. Gibbons and S.-T. Sun, “Optically generated liquid crystal gratings,” Appl. Phys. Lett. 65, 2542, 1994).
[0017] DWs are characterized by their efficiency, optical homogeneity, scattering losses, and size. While acceptable for research and development purposes, none of the techniques known in the prior art can be used for fabricating high quality DWs and their arrays in large area, inexpensively, and in high volume production. Since DWs consist of a pattern of optical axis orientation, they cannot be reproduced with conventional techniques used for gratings of surface profiles (J. Anagnostis, D. Rowe, “Replication produces holographic optics in volumes”, Laser Focus World 36, 107, 2000; M. T. Gale, “Replicated diffractive optics and micro-optics”, Optics and Photonics News, August 2003, p. 24).
[0018] It is the purpose of the present invention to provide method for the production of DWs of continuous patterns of optical axis orientation and controlling their spatial period. The printing method of the current invention does not require complex holographic setups, nor special alignment or vibration isolation as described in the publications S. R. Nersisyan, et al., “Optical Axis Gratings in Liquid Crystals and their use for Polarization insensitive optical switching,” J. Nonlinear Opt. Phys. & Mat., 18, 1, 2009; S. R. Nersisyan, et al., “Characterization of optically imprinted polarization gratings,” Appl. Optics 48, 4062, 2009 and N. V. Tabiryan, et al., “The Promise of Diffractive Waveplates,” Optics and Photonics News, 21, 41, 2010, which are incorporated herein by reference.
[0019] Energy densities required for printing DWs are essentially the same as in the case of producing a waveplate in a holographic process. This makes fabrication of diffractive waveplates much faster compared to mechanical scanning or rotating techniques. A technique for obtaining polarization modulation patterns avoiding holographic setups was discussed earlier in the U.S. Pat. No. 3,897,136 to 0. Bryngdahl. It discloses a grating “formed from strips cut in different directions out of linearly dichroic polarizer sheets. The gratings were assembled so that between successive strips a constant amount of rotation of the transmittance axes occurred.” These were also essentially discontinuous structures, with the angle between the strips π/2 and π/6 at the best. The size of individual strips was as large as 2 mm. Thus, such a grating modulated polarization of the output light at macroscopic scales and could not be used for production of microscale-period gratings with diffractive properties at optical wavelengths.
BRIEF SUMMARY OF THE INVENTION
[0020] Thus, the objective of the present invention is providing means for fabricating high quality DWs in large area, typically exceeding 1″ in sizes, in large quantities, high yield, low cost.
[0021] Another objective of the present invention is providing means for fabricating DWs with different spatial periods of optical axis modulation.
[0022] Still another objective of the present invention is using radiation of visible wavelengths for fabricating DWs.
[0023] In one embodiment, the invention, particularly, includes converting a linear or unpolarized light, generally non-monochromatic, incoherent or partially coherent, into a light beam of a periodic pattern of polarization modulation and subjecting materials with capability of photoalignment to said pattern for time periods nearly an order of magnitude exceeding the times otherwise required for obtaining homogeneous orientation state.
[0024] Further objectives and advantages of this invention will be apparent from the following detailed description of presently preferred embodiment, which is illustrated schematically in the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0025] FIG. IA shows the schematic of printing DWs.
[0026] FIG. IB schematically shows distribution of light polarization at the output of the linear- to-cycloidal polarization converter.
[0027] FIG. IC schematically shows distribution of light polarization at the output of a linear- to-axial polarization converter.
[0028] FIG. ID schematically shows distribution of light polarization at the output of a two-dimensional cycloidal polarization converter.
[0029] FIG. 2A shows the schematic of printing DWs using a CDW as a polarization converter.
[0030] FIG. 2B shows achromatic polarization conversion capability of twist nematic liquid crystals.
[0031] FIG. 3 shows spatial frequency doubling of a CDW in the printing process. Photos are obtained under polarizing microscope with IOO× magnification.
[0032] FIG. 4 shows two consecutive doubling of the order of an axially symmetric DW.
[0033] FIG. 5 shows photos of the structure of CDWs obtained under polarizing microscope for different exposure times. Photos are obtained under polarizing microscope with 40× magnification.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Before explaining the disclosed embodiment of the present invention in detail it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not limitation.
[0035] The preferred embodiment of the present invention shown in FIG. IA includes a light beam 101 incident upon an optical component 102 capable of converting the incident light beam 101 into a beam with spatially continuous modulated polarization pattern 103 . Of particular interest are “cycloidal” and axial modulation patterns shown schematically in FIG. IB and FIG. IC, correspondingly, wherein the numerals 106 indicate the linear polarization direction at each point of the plane at the output of the polarization converter (S. R. Nersisyan, et al., “Characterization of optically imprinted polarization gratings,” Appl. Optics 48, 4062, 2009). One polarization modulation period is shown in FIG. IB, and the polarization direction is reversed 4 times for the example of the axially modulated pattern shown in FIG. IC. Polarization modulation may have other distributions as exemplified by the two-dimensional cycloidal pattern shown in FIG. ID.
[0036] A photoresponsive material film 104 capable of producing an internal structure aligned according to the polarization pattern 103 , deposited on a substrate 105 , is arranged in the area with spatially modulated polarization pattern. Examples of such materials include photoanisotropic materials such as azobenzene or azobenzene dye-doped polymers, and photoalignment materials such as azobenzene derivatives, cinnamic acid derivatives, cournarine derivatives, etc.
[0037] Light beams of UV wavelengths are typically used for the photoalignment process, particularly when involving linearly polymerizable polymers. Certain azobenzene dyes, however, such as PAAD-27 commercially available at www.beamco.com, have peak absorption band at visible wavelengths and allow using beams of visible wavelengths of such common lasers as Argon-Ion (514 nm) and the second harmonic of Nd:YAG (532 nm) for photoalignment. Using radiation of visible wavelength has other advantages important from production standpoint. Unlike UV optics, the optical components, including polarizers, and optical coatings for visible wavelengths used in current invention do not quickly deteriorate in time when subject to radiation, and they are substantially less expensive compared to optical components and coatings for UV beams.
[0038] Any of the diffractive waveplates shown in FIG. IB, FIG. IC and FIG ID can be used as a polarization converter 102 in FIG. IA. Note that the diffractive waveplates in FIG. 1 are shown as examples only, and not for limitation. In the preferred embodiment of the present invention, any other diffractive waveplate that converts an input coherent beam into a spatially modulated linear polarized beam can be used in the scheme shown in FIG. IA.
[0039] In the particular example shown in FIG. 2A , a CDW is used as pblarization converter 102 . In order for a CDW to act as a polarization converter that generates cycloidal polarization modulation pattern in the overlap region of the diffracted beams 107 and 108 , the input light needs to be polarized and coherent. By that, half-wave phase retardation condition, L(n e −n 0 )=λ/2, where n e and n 0 are the principal values of refractive indices of the CDW used as a converter, and L is its thickness, needs to be met for the wavelength of a linear polarized input beam, and quarter-wave phase retardation condition, L(n e −n 0 )=λ/2, needs to be met for a circularly polarized input beam.
[0040] Both conditions specified in the current invention ensure linearly polarized output beam with spatially modulated polarization direction. Diffractive waveplates of spectrally broadband or achromatic performance can be used in the preferred embodiment as far as it includes the wavelength of radiation used for fabrication.
[0041] Polarization converters of current invention may be recorded holographically or obtained by other means. Holographic techniques do not apply to vortex waveplates (ADWs) and to more general patterns of aperiodic and/or nonlinear variation of optical axis orientation. “Pancharactnam lens” is an example of nonlinear variation of the optical axis orientation angle a with the polar coordinate r, α˜r 2 (Marrucci, et al., “Pancharatnam-Berry phase optical elements for wave front shaping in the visible domain: Switchable helical mode generation,” Appl. Phys. Lett. 88, 221102 (1-3), 2006).
[0042] ADWs, for example, can be fabricated by mechanical circular buffing not even involving any photoresponsive polymer (M. Stalder, M. Schadt, “Linearly polarized light with axial symmetry generated by liquid-crystal polarization converters”, Optics Letters Vol. 21, No. 23, pp. 1948-1950, 1996) or rotating the photoresponsive film in a strip of a linearly polarized light (N. V. Tabiryan, S. R. Nersisyan, H. Xianyu, E. Serabyn, Fabricating Vector Vortex Waveplates for Coronagraphy, Aerospace Conference, 2012 IEEE, pp 1-12). Cycloidal diffractive waveplates can also be fabricated using mechanical microrubbing with no photoalignment or otherwise photoresponsive films involved (M. Honma and T. Nose, “Polarization-independent liquid crystal grating fabricated by microrubbing process,” Jpn. J. Appl. Phys., Part 1, Vol. 42, 6992-6997, 2003).
[0043] A twisted nematic LC cell shown in. FIG. 2B is an example of a broadband polarization rotator that does not need to fulfill half-wave phase retardation condition (P. Yeh, C. Gu, Optics of Liquid Crystal Displays, Wiley, 2010, Section 4.3). The polarization of a linear polarized input light 201 propagating in a material where the molecules of the LC 204 rotate between the substrates 201 due to differently aligning conditions at the cell boundaries 203 follows the rotation of the LC orientation. Thus, the polarization of a light beam 205 is rotated at the exit of the cell at an angle determined by the orientation of the LC, hence, spatially modulating the LC rotation angle at the output substrate allows to spatially modulate the light polarization at the output of the device. The condition of so-called adiabatic following of polarization with rotation of the optical axis is met for all wavelength where λ.<<L(n e −n 0 ) as well known in the prior art (P. Yeh, C. Gu, Optics of Liquid Crystal Displays, Wiley, 2010, Section 4.3).
[0044] Note that the light field at the output of the polarization converter can further be processed by optical projection and transformation means to widen the types of patterns that could be created. As an example, adding a polarizer at the output of the DW transforms the polarization modulation pattern into a pattern of intensity modulation that could be used for printing a variety of diffractive optical elements.
[0045] The simplicity of this method, its insensitivity to vibrations, noises, air flows, as opposed to the holographic techniques makes feasible manufacturing high quality DWs with high diffraction efficiency in large areas exceeding 1 inch in sizes and in large quantities with low cost.
[0046] A spatial light modulator was suggested by Konawa for polarization modulation in U.S. Patent Application US2001/0002895. Such a component is binary with two states only, p-polarization and s-polarization at application or non-application of voltage. The spatial light modulator used in Kawano's device does not provide an opportunity for rotating the polarization of light at any angle other than 90 degrees with respect to the incident beam polarization.
[0047] In contrast, the polarization converters used in our application have continuous structure with no pixels and provide light field with continuously modulated polarization. They are suitable for printing diffractive waveplate structures with high spatial resolution that cannot be achieved in pixelated systems.
[0048] The spatial period of the printed DW is equal to that of the DW used as a polarization converter when a circular polarized light is used in conjunction with a DW that meets quarter-wave phase retardation condition for the radiation wavelength. A linear polarized light, however, yields in a DW with twice shorter period of the optical axis modulation. This is evident, FIG. 3 , in the photos of the structure of the DW 301 produced via printing using a linear polarized light beam as compared to the structure of the DW 302 used as a polarization converter. Photos were obtained under polarizing microscope with IOO× magnification (S. R. Nersisyan, et al., “Characterization of optically imprinted polarization gratings,” Appl. Optics 48, 4062, 2009). This applies both to CDWs as well as to the diffractive waveplates with axial symmetry of optical axis orientation (ADWs) shown in FIG. 4 wherein the numeral 401 corresponds to the ADW used as a polarization converter, and 402 corresponds to the ADW obtained as a result of printing (N. V. Tabiryan, S. R. Nersisyan, D. M. Steeves and B. R. Kimball, The Promise of Diffractive Waveplates, Optics and Photonics News 21, 41, 2010). The technique of doubling the spatial frequency allows producing high degree ADWs and their arrays without using mech(Inical rotating setups.
[0049] Each DW in these examples was obtained by deposition of a LC polymer on the substrate carrying the photoalignment layer. This process of LC polymer deposition involves spin coating, heating to remove residual solvents, and polymerization in an unpolarized UV light. Other coating techniques (spray coating, as an example) and polymerization techniq ues (heating, as an example) are known and can be used for this purpose. The period of the printed DWs can be varied also by incorporating an optical system that projects the cycloidal polarization pattern onto larger or smaller area or, in a preferred embodiment of the current invention, by combining, for example, CDWs in series. The diffraction angle, hence the pitch of the cycloidal pattern of polarization modulation in the overlap of the diffracted beams, may be continuously varied from 0 to double the angle achieved with a single CDW for different mutual orientations of CDWs. (S. R. Nersisyan, N. V. Tabiryan, L. Hoke, D. M. Steeves, B. Kimball, Polarization insensitive imaging through polarization gratings, Opt. Exp. 17 (3), 1817-1830, 2009).
[0050] Another aspect of the present invention consists in the disclosure that the photoalignment materials need to be exposed to cycloidal polarization pattern of radiation for time periods considerably exceeding the exposure time required for obtaining homogeneous aligning films at a given power density level of radiation. As an example, ROLIC Ltd. specifies 50 mJ/cm 2 exposure energy density for its material ROP 103 at the wavelength 325 nm. Exposure with such an energy density yields in good homogeneous alignment, however, the structure of CDWs fabricated according to that recipe appears very poor under polarizing microscope as shown in FIG. 5 . Extending the exposure time improves the structure, and practically defect-free structure is obtained for exposure energies >1 J/cm 2 that is 20× exceeding the specified values for this particular material.
[0051] An exposure dose range 0.5-2 mJ/cm 2 is specified by Escuti et al., “Polarization-independent LC microdisplays using liquid crystal polarization grating” A viable solution? “Presentation slide” July 2008 at ILCC'08 (30 pages). Note again that this statement is valid, only in part, for the particular material, ROP-103 from Rolic Ltd. in combination with the particular LC (MLC-12100 from Merck). As an example, the paper “Liquid-crystal diffraction gratings using polarization holography alignment techniques” by Crawford et al., published in J. of Appl. Phys., vol. 98, 123102, 2005, comments on the attempt of fabricating a polarization grating using a reactive mesogen (page 7): “Inspection of the microscope photograph in FIG. 9 b shows a significant number of defects. These defects are attributed to the top air surface, which does not enforce planar anchoring conditions. One can of course use reactive mesogen materials and two aligning surfaces as described in Sec. IV A, to achieve near perfect alignment as observed in low molecular weight systems.” Note “near perfect alignment” for low molecular weight LCs and “significant number of defects” for a reactive mesogen.
[0052] As another example, as disclosed in S. R. Nersisyan, et al., “Optical Axis Gratings in Liquid Crystals and their use for Polarization insensitive optical switching,” J. Nonlinear Opt. Phys. & Mat., 18, 1-47, 2009, the photoalignment material ROP-203, also from Rolic Ltd., allows producing defectless and haze-free LC polymer polarization gratings for exposure dose of only 120 mJ/cm 2 .
[0053] Thus, no exposure energy range can be specified as having significance for the technology in general. Our disclosures that:
[0000] a) there is a relationship between the defective structure and the exposure energy, and
b) that defectless and haze-free DWs can be manufactured by increasing the anchoring strength of the photoalignment layer by means, in particular, of the increased exposure energy, and
c) that the exposure energy required for such defectless and haze-free liquid crystal polymer DWs needs to be at least an order of magnitude higher than the energy required for obtaining homogeneous oriented LCP films (which is namely the parameter specified by material manufacturers), were neither understood nor used before.
[0054] The quality of DWs fabricated in conventional holographic process depends on many factors: the quality of the overlapping beams; the susceptibility of the holographic setup to mechanical vibrations and air fluctuations in the path of the beam; the coherence of the beams and equality of their paths; depolarization effects due to propagation of the beams through multiple optical elements such as lenses and beam splitters; the quality of the substrate; the qualities of the photoalignment materials, their affinity with the substrate in use and the effects of coating and solvent evaporation processes. These factors include the homogeneity of the LCs layer thickness, and their compatibility issues with the photoalignment layer. The compatibility of the LC materials with the photoalignment material is important as well. Typical thickness of these films is in the micrometer range, whereas thickness variation for as little as the wavelength of radiation, ˜0.5 μm for visible wavlengths, can dramatically affect the diffraction efficiency of those components. The absolute value of the thickness is as important due to orientation instabilities that is determined, among other things, by the ratio of the layer thickness to the modulation period (H. Sarkissian, et al., “Periodically aligned liquid crystal: potential application for projection displays,” Mol. Cryst. Liquid Cryst., 451, 1, 2006).
[0055] Among all these factors, the exposure energy, being a parameter easy to control and specified by its supplier appears to be the least suspected to affect the quality of the DW being fabricated. With all the noises, impurities, and uncertainties in man y steps involved in the process, the obtained component would still show relatively small areas of good quality, good enough for research, but beyond the acceptable limits for practical applications. Thus, relating the component imperfections to the exposure energy and the finding that the exposure times shall considerably exceed photoaligning material specifications provided for homogeneous orientation is critically important for fabrication of high quality DWs with homogeneous properties in a large area.
[0056] The reasons for such an effect of the exposure time lie, apparently, in the need to produce stronger forces to support a pattern of spatial modulation of the optical axis than those required for homogeneous alignment. Elastic forces against modulation of molecular orientation are strong in LC materials. Longer exposure induces stronger modulation of the microscopic orientation properties of the photoaligning materials. Anchoring energy of such materials for LCs are not comprehensively studied. The available data relate to homogeneous orientation (V. G. Chigrinov, et al., “Photoaligning: physics and applications in liquid crystal devices”, Wiley VCH, 2008).
[0057] Due to robustness of the printing method to the mechanical and other ambient noise, large area components can be fabricated by continuously translating the substrate in the region of cycloidal polarization pattern. By that, the energy of the light beam can be distributed along a long strip to produce a larger photoalignment area.
[0058] Although the present invention has been described above by way of a preferred embodiment, this embodiment can be modified at will, within the scope of the appended claims, without departing from the spirit and nature of the subject invention. | An apparatus and method is presented for fabricating high quality one- or two dimensional diffractive waveplates and their arrays that exhibit high diffraction efficiency over large area and being capable of inexpensive large volume production. Employed is a generally non-holographic and aperiodic polarization converter for converting the polarization of a coherent input light beam that may be of a visible wavelength into a pattern of continuous spatial modulation at the output of said polarization converter. A photoresponsive material characterized by an anisotropy axis that may be formed or aligned according to polarization of said light beam is exposed to said polarization modulation pattern and may be coated subsequently with an anisotropic material overlayer. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional of and Applicants claim priority under 35 U.S.C. §§120 and 121 of U.S. application Ser. No. 12/734,241 filed on Sep. 2, 2010, which application is a national stage application under 35 U.S.C. 371 of PCT Application No. PCT/DE2008/001696 filed on Oct. 17, 2008, which claims priority under 35 U.S.C. §119 from German Patent Application No. 10 2007 050 213.5 filed on Oct. 20, 2007, the disclosures of each of which are hereby incorporated by reference. A certified copy of priority German Patent Application No. 10 2007 050 213.5 is contained in parent U.S. application Ser. No. 12/734,241. The International Application under PCT article 21(2) was not published in English.
BACKGROUND OF THE INVENTION
The present invention relates to a multi-part piston for an internal combustion engine, having an upper piston part and a lower piston part, whereby the upper piston part has a piston crown, a circumferential top land, as well as a circumferential ring belt, whereby the upper piston part and the lower piston part are connected with one another by means of attachment means and form a circumferential cooling channel.
In the case of such known multi-part cooling channel pistons, the problem exists of reliably connecting the upper piston part and the lower piston part with one another, while avoiding stresses. Furthermore, optimization of the cooling effect of the cooling oil contained in the cooling channel is aimed at. The cooling oil circulates in the cooling channel and is moved as a result of the shaker effect that is brought about by the piston movement. In DE 102 44 512 A1, it is proposed to provide the circumferential cooling channel with bores that are directed toward the piston crown, in order to achieve a better distribution of the cooling oil. However, in the case of pistons that are subject to great stress, in particular, the heat dissipation brought about by the movement of the cooling oil is not sufficient.
The present invention is therefore based on the task of creating a multi-part piston of the type indicated, having an improved cooling effect of the cooling oil that circulates in a cooling channel, in which piston the upper piston part and the lower piston part are reliably connected with one another.
SUMMARY OF THE INVENTION
To accomplish this task, the present invention comprises a multi-part piston having attachment means that connect the upper piston part and the lower piston part. The attachment means are configured as cooling elements made of a heat-conductive material and disposed in the cooling channel.
The piston according to the invention is characterized by an improved cooling effect, which has several causes. The cooling elements represent an additional cooling surface in the cooling space, by way of which the heat transported from the piston crown to the cooling elements is given off to the cooling oil that flows around the cooling elements. Furthermore, a directed flow of heat from the piston crown to the cooling oil, by way of the cooling elements, is guaranteed, and this, in particular, quickly and reliably reduces the heat stress on the piston crown, which faces the combustion chamber. In addition, heat dissipation from the cooling element into the lower piston part takes place. In the case of pistons whose piston crown is provided with a combustion chamber bowl, the bowl edge, in particular, is relieved of stress in particularly effective manner in this way.
The attachment means, which are configured as cooling elements, are uniformly distributed in a radially outer region of the piston, i.e. in the immediate vicinity of the ring belt, namely in the circumferential cooling channel, so that a particularly low-stress and reliable connection of upper piston part and lower piston part is achieved. Furthermore, the attachment means, which are configured as cooling elements, bring about an improvement in the shape stability of the piston according to the invention. For this reason, it is possible to configure the piston according to the invention, despite the cooling elements that are provided, in such a manner that a weight increase in comparison with conventional pistons is avoided. This can be brought about in that on the one hand, a suitable material, having as low a density as possible, is selected for the cooling elements, and that on the other hand, the wall thicknesses, particularly between the circumferential cooling channel and the adjacent structural elements, can be reduced because of the improved shape stability. In the case of a suitable method of construction, a weight reduction in comparison with conventional pistons is actually possible.
The embodiment according to the invention is suitable for all types of multi-part pistons, and allows a plurality of variants with regard to material selection and design. The piston according to the invention can consist, for example, of steel, cast iron, light metal, as well as a combination of these materials, and it can be configured with or without oil injection, for example.
Every cooling element, i.e. every attachment means configured as a cooling element, is accommodated in two recesses, one of which is provided in the upper piston part, and one in the lower piston part. The recesses provided in the lower piston part can be configured, for example, as dead-end bores or as passage bores. Therefore the cooling elements can be inserted into the upper piston part or the lower piston part, for example, in simple manner, if necessary oriented in known manner, using a centering ring, and the missing piston part can be pushed onto the cooling elements, so that these engage into the corresponding bores. Attachment of the cooling elements preferably takes place by means of press fit or shrink fit.
The recesses provided in the upper piston part in this embodiment bring about a further reduction in material thickness toward the piston crown. In a particularly advantageous embodiment, the material thickness toward the bowl edge is reduced if the piston crown is provided with a combustion chamber bowl. This brings about a further improved and accelerated transport of heat to the cooling elements. The cooling elements simultaneously ensure sufficient shape stability of the piston according to the invention, in that the cooling elements balance out possible stability losses brought about by the recesses. This has the result that the diameter of a combustion chamber bowl provided in an individual case can be further increased as compared with the state of the art. This in turn once again improves the heat dissipation in the direction of the cooling elements, and from there to the cooling oil. The number of cooling elements can be selected to be particularly large, because of the improved shape stability, so that the effective cooling surface is optimized. In addition, the heat taken up by the piston crown is prevented from penetrating into the region of the ring belt.
Another suitable embodiment provides for ring-shaped cooling elements, which can be provided with passage openings for the cooling oil, if necessary, in order to optimize mixing of the cooling oil. A particularly preferred embodiment of the piston according to the invention consists in that pin-shaped cooling elements are provided. This configuration is accompanied by the greatest possible increase in the cooling surface, so that particularly effective heat dissipation from the cooling elements to the cooling oil takes place.
The cooling elements are preferably configured as solid metal cooling elements, and consist, for example, of copper, aluminum, or their alloys.
In a preferred embodiment, the upper piston part and the lower piston part additionally form an inner cooling chamber, which is separated from the circumferential cooling channel by a circumferential partition, to support the cooling effect. The upper piston part and the lower piston part can have additional connection elements in the region of the partition, which support the connection of upper piston part and lower piston part. These connection elements also can be configured as cooling elements, to further improve the cooling effect.
In an advantageous manner, the partition can have at least two overflow openings for cooling oil, which connect the circumferential cooling channel and the inner cooling chamber with one another, in order to optimize mixing of the cooling oil.
The materials for the upper piston part and the lower piston part can be selected and combined with one another as desired. For example, steel materials and light-metal materials are suitable.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention will be described in the following, using the attached drawing. The drawing shows, in a schematic representation, not true to scale:
FIG. 1 a section through a first exemplary embodiment of a piston according to the invention;
FIG. 2 the piston according to FIG. 1 in a top view, partly in section;
FIG. 3 an enlarged detail of a second exemplary embodiment of a piston according to the invention, in section;
FIG. 4 an enlarged detail of an upper piston part for a third exemplary embodiment of a piston according to the invention, in section.
DETAILED DESCRIPTION OF THE EMBODIMENTS
FIGS. 1 and 2 show a first exemplary embodiment of a piston 10 according to the invention, whereby the representation according to FIG. 1 is rotated by 90° in the left half, as compared with the representation in the right half.
The piston 10 according to the invention is composed of an upper piston part 11 and a lower piston part 12 . The upper piston part 11 has a piston crown 13 having a combustion chamber bowl 14 as well as a side wall having a circumferential top land 15 and a circumferential ring belt 16 for accommodating piston rings (not shown). The lower piston part 12 has a piston skirt 17 , pin bosses 18 having pin bores 18 a for accommodating a piston pin (not shown), and pin boss supports 19 that are connected with the piston skirt 17 . The upper piston part 11 and the lower piston part 12 form a circumferential outer cooling channel 21 and an inner cooling chamber 22 , which are separated from one another by means of a partition 29 . In the exemplary embodiment, overflow channels 27 are provided in the partition 29 , which connect the cooling channel 21 and the cooling chamber 22 with one another.
The upper piston part 11 has an outer contact surface 23 that follows the ring belt 16 , and a ring-shaped, circumferential inner support surface 24 on its underside. The lower piston part 12 also has an outer contact surface 25 on its top, as well as a ring-shaped, circumferential inner support surface 26 . In the assembled state, the upper piston part 11 and the lower piston part 12 are oriented, relative to one another, in such a manner that the two support surfaces 24 , 26 as well as the two contact surfaces 23 , 25 lie against one another. The partition 29 is formed in the region of the support surfaces 24 , 26 , in the assembled state.
The materials of the upper piston part 11 and the lower piston part 12 can be selected and combined with one another as desired, for example hot steel, AFP steel, or light-metal alloys, particularly aluminum alloys. For example, the upper piston part 11 can be forged from hot steel, and the lower piston part 12 can be forged from AFP steel; however, the upper piston part 11 can also be forged from AFP steel, and the lower piston part 12 can be cast from an aluminum alloy. However, the upper piston part 11 can also be forged from an aluminum alloy, and the lower piston part can be cast from an aluminum alloy.
In the exemplary embodiment, a plurality of pin-shaped attachment means configured as cooling elements 28 are disposed in the cooling channel 21 of the piston 10 . The cooling elements 28 consist of a material that conducts heat well, preferably having a low density. Metallic materials such as aluminum, copper, or their alloys, for example, are suitable. The free ends of the cooling elements 28 are accommodated in recesses 31 , 32 configured as bores. The recess 31 , configured as a dead-end bore, is disposed in a wall section of the cooling channel 21 formed by the upper piston part 11 , and is directed toward the piston crown 13 . The recess 32 , configured as a passage bore, is disposed in a wall section of the cooling channel 21 formed by the lower piston part 12 . The cooling elements 28 are attached in the upper piston part 11 and in the lower piston part 12 by means of a press fit or shrink fit, in the exemplary embodiment.
The cooling elements 28 are therefore simultaneously attachment means, by means of which the upper piston part 11 and the lower piston part 12 are connected with one another essentially without any tension. This is attributable to the fact that the attachment means are disposed, uniformly distributed, in a radially outer region of the piston 10 , i.e. in the immediate vicinity of the ring belt 15 , namely in the circumferential cooling channel 21 . Furthermore, the attachment means, which are configured as cooling elements 28 , bring about an improvement in the shape stability of the piston 10 according to the invention. For this reason, the wall thickness between the combustion chamber bowl 14 and the recesses 31 is configured to be particularly small. This is accompanied by a reduction in material and weight. Furthermore, the heat from the combustion chamber bowl 14 is passed off to the cooling elements 28 particularly quickly.
The surfaces of the numerous cooling elements 28 act as an additional large cooling surface in the cooling channel 21 . By way of this cooling surface, the heat transport from the piston crown 13 to the cooling elements 28 is given off to the cooling oil that flows around the cooling elements 28 particularly quickly. Furthermore, a direct heat flow from the piston crown 13 to the cooling channel 21 , and from there both to the cooling oil and to the lower piston part 12 , is guaranteed, and this reduces the heat stress on the piston crown 13 and on the bowl edge of the combustion chamber bowl 14 , in particular, in particularly effective manner.
In the exemplary embodiment shown in FIG. 1 , pin-shaped connection elements 30 are furthermore provided in the partition 29 , which elements, comparable to the attachment means configured as cooling elements 28 , are accommodated in recesses provided in the upper piston part 11 and the lower piston part 12 , respectively, for example by means of press fit or shrink fit. The connection elements 30 support the connection between the upper piston part 11 and the lower piston part 12 brought about by the attachment elements configured as cooling elements 28 . The connection elements 30 can also be configured as cooling elements, in order to support the heat dissipation from the piston crown 13 to the lower piston part 12 .
FIG. 3 shows, as a detail, another exemplary embodiment of a multi-part piston 110 , whereby the same reference symbols were used for the same components. In FIG. 3 , only part of the upper piston part 11 and part of the lower piston part 12 , as well as the cooling channel 21 and a cooling element 128 are shown. The piston 110 has the same structure as the piston 10 shown in FIG. 1 . The only difference consists in that the lower free ends of the cooling elements 128 are accommodated in recesses 132 provided in the lower piston part 12 and configured as dead-end bores. The upper, free ends of the cooling elements 128 are accommodated in recesses 31 configured as dead-end bores, which are provided in the upper piston part 11 , just as in the piston 10 . In this exemplary embodiment, too, the cooling elements 128 can be attached by means of press fit or shrink fit. The cooling elements 128 have the same effects and advantages as those described for the cooling elements 28 according to FIG. 1 .
FIG. 4 shows, as a detail, another exemplary embodiment of an upper piston part 11 of a multi-part piston 210 , which is the same as the piston 10 and 110 shown in FIGS. 1 and 3 , respectively. It can be seen that connection elements 30 are disposed in the region of the partition 29 . The only difference consists in that in place of pin-shaped cooling elements, cooling elements 228 configured in the shape of ring segments are provided. The upper free ends of the cooling elements 228 are accommodated, in comparable manner, in recesses (not shown), which are disposed in a wall section of the cooling channel 21 formed by the upper piston part 11 . The cooling elements 228 are attached in suitable manner, as described above, for example by means of shrink fit or press fit. In the assembled state, the lower free ends of the cooling elements 228 are accommodated and attached in recesses (not shown) provided in the lower piston part, in comparable manner. The cooling elements 228 have passage openings 239 , in order to guarantee optimal mixing of the cooling oil accommodated in the cooling channel 21 . The cooling elements 228 demonstrate the same effects and advantages as described for the cooling elements 28 according to FIG. 1 . | A multi-part piston for an internal combustion engine has a piston upper part and a piston lower part. The piston upper part comprises a piston head, a continuous fire land and a continuous ring part. The piston upper part and the piston lower part are connected together by securing means and form a continuous cooling channel. According to the invention, the connecting means connecting the piston upper part and the piston lower part are embodied as cooling elements that are arranged in the cooling channel and that are made of heating-conducting material. | 5 |
BACKGROUND OF THE INVENTION
[0001] The invention relates to renovation of pipelines, such as drainpipes, with a lining technique. The invention particularly relates to branch pieces to be used when branch points are being lined and to lining of the branch points.
[0002] Pipe systems, for example drainpipe systems of buildings, are typically renovated by replacing the pipes with completely new ones or by coating the inner surfaces of existing pipes with an appropriate coating technique and coating material. When the pipes in a building are replaced with completely new ones, often structures of the building have to be destructed by chipping, for instance, so that old pipes can be detached from the walls of the building. It is expensive, dirty and time-consuming work to destruct and rebuild wall structures. Because of the noise and dust caused by the renovation work it is often impossible to live in the premises during the renovation work.
[0003] Pipelines may also be renovated by coating the inner surfaces thereof. One technique of this sort is a so-called lining technique, in which a liner is slipped into a sewer to be repaired and is impregnated with a special epoxy resin which forms, when hardening, a continuous and leak-proof pipe that is i.a. self-supporting, acid-proof, food-grade and environmentally friendly. The wall thickness of the pipe liner is, depending on the size of the pipe, 2 to 4 mm, and its smooth inner surface guarantees excellent flow properties. The durability, environmental safety and service life of the pipe having been installed in place and hardened are comparable with corresponding properties of new pipes.
[0004] Problems in lining are caused by branch points in the pipeline, which also must be lined and made leak-proof. A prior art solution uses a branch pipe sewn of the same lining material that is used for lining the rest of the pipeline. Lining of a branch point begins by cleaning, after which the vertical pipe is lined and the lining is left to harden. The branch point is opened by drilling a hole in the lining of the vertical pipe, the branch piece being then slipped into the branch point and installed in place. Finally, the branch pipe is lined in a partly overlapping manner together with the part of the branch piece that enters the branch. When all the parts have hardened, the result of the work is inspected.
[0005] A problem with the arrangement described above is the high probability of a failed installation and a slow installation process involving multiple steps. Taking an epox-impregnated branch piece to the branch point and setting it in place is difficult and time-consuming. Moreover, some of the epoxy easily adheres to the pipes along the way as the branch piece is being taken to the branch point, and, as the epoxy dries, sharp epoxy spikes are left in the already lined vertical pipe, the spikes catching dirt when the sewer is used and thus blocking the pipe easily. Installing the branch pipe requires special tools whose service life extends for some installations only because they get easily caught in the drying epoxy and the tools have to be removed from pipe by force. In addition, the end result of the branch piece installation can only be inspected after the epoxy has dried and the branch piece has settled in place, so a failed installation is extremely laborious and time-consuming to remove.
BRIEF DESCRIPTION OF THE INVENTION
[0006] An object of the invention is thus to provide a branch piece and a method so as to enable the aforementioned problems to be solved. The object of the invention is achieved with a branch piece and a method that are characterized by what is stated in the independent claims. Preferred embodiments of the invention are disclosed in dependent claims.
[0007] The invention is based on using an elastic, metal-reinforced branch piece which does not need to be impregnated with epoxy and which is made in the shape of the branch point to be renovated. According to the method, the branch piece is placed into the pipe before lining and the vertical pipe is lined through the branch piece.
[0008] An advantage of the branch piece and the method of the invention is that the installation is clean, rapid and easy because the branch piece is not impregnated with epoxy. The branch piece may be properly installed in place first and only after a successful installation of the branch pipe is confirmed, lining is started. If deficiencies in the installation of the branch piece are observed, the position of the pipe can still be fixed, or the branch piece may even be replaced by an entirely new one before lining. With this procedure, the renovation of a branch point succeeds practically always.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The invention is now described in closer detail by means of preferred embodiments and with reference to the accompanying drawings, in which:
[0010] FIG. 1 shows a branch piece according to an embodiment of the invention;
[0011] FIG. 2 shows a structure of walls of a branch piece according to an embodiment of the invention; and
[0012] FIG. 3 shows a cross-section of a branch point renovation carried out with a branch piece according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0013] With reference to FIG. 1 , a branch piece 10 comprises a main line pipe 11 and a branch pipe 12 . The main line pipe is typically installed to a vertical line and is therefore also sometimes referred to as a vertical pipe. However, the main line pipe 11 may also be installed to a horizontal main line or to a main line running in any orientation. One or more branch pipes 12 may be provided. FIG. 1 shows what is perhaps the most typical branch point seen in a block of flats, i.e. a so-called Y branch, in which a branch line connects with the main line at an angle of about 45 degrees. When the branch pipe 12 is a T branch, for example, it may be at an angle of 90 degrees or at almost any other angle, depending on the branch point to be renovated. A main line having a plural number of branches connecting with it on a short distance, a branch piece with a plurality of branch pipes 12 may be used or, possibly, the main line pipe 11 of the branch piece may be shortened so that all branches may be covered with their specific branch pieces without the main line pipes of the different branch pieces overlapping.
[0014] A branch piece 10 preferably comprises a three-layer structure consisting of an inner sheathing 20 and an outer sheathing 24 , with a reinforcement layer 22 between them. The reinforcement layer 22 preferably covers the area of the branch piece 10 entirely or almost entirely, although exceptions to this are possible. According to an embodiment, only the branch pipe 12 is provided with the reinforcement layer 22 . According to an embodiment, the branch pipe 12 and the ends of the header pipe 11 are provided with the reinforcement layer 22 . According to an embodiment, the reinforcement layer 22 is provided everywhere, except at the junction between the main line pipe 11 and the branch pipe 12 .
[0015] The inner and outer sheathings of the branch piece are preferably of an elastic material, the branch piece 10 thus being compressible by taping or tying it with a string before it is pushed into the pipe, and the compressed piece may be taken to the branch point of renovation, where the strings or the tape is removed and the branch piece 10 tends to regain its shape. Its return to shape may be facilitated e.g. by pulling the branch pipe from the branch, using an expanding tool matching the branch piece in shape and positioning the branch piece, or by other known means. The elastic material to be used is preferably latex, although other elastic materials, such as synthetic rubber or silicone, may also be used. It is also possible to make the inner and/or outer sheathing of the branch piece of a non-elastic material, provided that the reinforcement layer is made so that it is able to return the branch piece back to its shape after the compression.
[0016] FIG. 2 shows a branch piece 10 according to an embodiment with its outer sheathing 24 between the header pipe 11 and the branch pipes 12 removed, thus disclosing the structure of the piece in greater detail. According to an embodiment, the branch piece 10 is made by providing an inner sheathing 20 of latex having a thickness of about 1 to 5 mm, preferably about 2 to 4 mm. The inner sheathing may be vulcanized. Onto the inner sheathing 20 , a reinforcement layer 22 made of a wire mesh, metal wires or wire cable is provided. A preferred structure for the reinforcement layer 22 is one that allows the branch piece to expand so that the diameter of the header pipe 11 , that of the branch pipe 12 or those of both the pipes may increase without the reinforcement layer being broken. According to an embodiment, the reinforcement layer 22 has a structure that does not allow the branch piece to expand so that the diameter of the header pipe 11 , that of the branch pipe 12 or those of both the pipes may increase without the reinforcement layer being broken. The structure of the reinforcement layer 22 of FIG. 2 , where the reinforcements in the direction of the longitudinal axis of the pipe are straight and the reinforcements surrounding the pipe are undulating, achieves a structure that allows an increase in the diameters of the pipes but not in their length. According to an embodiment, only undulating reinforcements surrounding the pipe may be used in the reinforcement layer. The reinforcements used in the reinforcement layer are preferably wire cable, for example, because it sustains wear well and has elastic properties. Finally, an outer sheathing of latex having a thickness of about 1 to 5 mm, preferably 2 to 4 mm is provided on the reinforcement layer 22 . Also the outer sheathing may be vulcanized. Consequently, a branch piece with a reinforcement layer 22 between an elastic inner sheathing and outer sheathing 24 is obtained, the entire structure regaining its shape after compression, whereby the branch piece may be successfully taken to the branch point and easily mounted in place.
[0017] FIG. 3 shows a cross-section of a lining of a branch point of a pipeline implemented with a branch piece 10 according to an embodiment. The procedure starts by cleaning the pipeline to be installed, if necessary. The branch piece is compressed by making a fold on the branch pipe 12 side of the main line pipe 11 , then pressing the branch pipe inside the fold, winding a tape or a string around the tubular piece thus obtained and, finally, slipping the piece to the branch point to be renovated. At the branch point the tape or string that keeps the branch piece compressed is removed from around the compressed branch piece, and due to its elastic properties the branch piece tends to unfold. The unfolding is assisted for example by rotating the branch piece about the longitudinal axis of the main line 31 and by moving the branch piece to and fro in the main line 31 , the branch pipe of the branch piece 10 thus setting in the branch line 32 of the pipeline. To make sure that the installation of the branch piece 10 is successful, the branch point may be recorded from both lines with a camera designed for video inspection of pipelines.
[0018] When the branch piece has been installed, the main line 31 , which in FIG. 3 is a vertical line, is lined as usual with a lining 41 . The lining 41 in the main line 31 is opened at the branch point by drilling, grinding and/or milling a hole in the lining 41 of the main line through the branch line 32 . No obstacles to the flow of sewer waste should be left between the branch line and the main line and therefore the branch line hole in the lining of the vertical line is preferably ground to be level with the branch piece. The reinforcement layer achieved inside the branch piece prevents the branch piece from getting worn out when an opening for the branch line is being worked in the lining 41 of the vertical line.
[0019] When the main line has been lined and the branch opened, the branch line 32 is lined in a normal manner so that the branch line lining 42 extends to the branch pipe of the branch piece. Preferably, the branch line lining 42 does not extend through the branch pipe all the way to the main line pipe and thus the branch line lining 42 does not need to be cut separately.
[0020] It is obvious to a person skilled in the art that as technology advances the basic idea of the invention may be implemented in many different ways. The invention and its embodiments are thus not restricted to the above-described examples but may vary within the scope of the claims. | The branch piece is for renovating a pipeline and has a main line pipe and at least one branch pipe connected with the main line pipe. The branch piece is elastic and has an inner sheathing, an outer sheathing and, at least on a part of the branch piece, a flexible reinforcement layer disposed between the inner sheathing and the outer sheathing. The branch piece regains its shape after compression. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority of the German patent application 101 15 837.8 which is incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The invention concerns a stand, in particular for a surgical microscope. The purpose of such stands is to hold a relatively heavy microscope so that it is movable by an operator with a minimum of resistance. An effort is therefore made to configure all joints, bearings, and the like in as low-resistance a fashion as possible, so that as little resistance as possible is presented to any arbitrary movement by the user.
BACKGROUND OF THE INVENTION
[0003] In surgery but also in other areas of technology, for example microelectronics, forensics, etc., more and more use is being made of surgical microscopes that, because of their heavy weight, must be supported by stands. Several well-known manufacturers have marketed stands that are well suited, in terms of mechanics and statics, for supporting the load of a surgical microscope. The present applicant, for example, markets stands with the designation OHS or MS1. One example of such a stand is found in EP-A-628290. Zeiss/Deutschland has disclosed a stand, for example, in EP-476552.
[0004] Many modern stands have parallelogram supports to allow the load of the surgical microscopes to be carried over the greatest possible distances with no bending or twisting, in order to maximize the freedom of movement and radius of action of the microscopes. In principle, however, the greater the radius of action, the greater the instability of a stand, except if appropriate design actions are taken against instability. However, the more rigid (less unstable) the structures, the more susceptible they are to vibratory behavior, which is similarly counteracted with design features such as selection of varying tube cross sections, material selection, use of damping elements, etc.
[0005] The transported weight of the stands also represents a problem whose solution lies fundamentally in weight reduction by means of high-strength materials.
[0006] For example, the present applicant has created a stand that uses at least one support made of a fiber-reinforced plastic. This stand is described in the aforementioned WO-A-97/20166.
[0007] It has been recognized, however, that weight reduction alone is not sufficient in some circumstances if the quality of the damping properties of the essential components is not sufficiently taken into account. Mere weight reduction results in some circumstances in intensified, higher-frequency vibratory behavior in the structure. This vibratory behavior is amplified in structures having braked arms. Brakes of this kind are to be operated electromagnetically, pneumatically, or even by hand, and create a rigid connection between the components, so that vibrations are transmitted from one component to another and result in a long vibration period that is annoying to the user.
[0008] The route of weight reduction by means of fiber composite materials and plastics has been taken in another sector of stand design, namely X-ray technology, as set forth in DE-C1-42 14 858. In this, a C-curve was created from plastic foam as the supporting part that determines the shape, which is surrounded by a fiber-reinforced plastic that assumes the support functions. If this known assemblage is to be particularly light in weight, then according to this previously published teaching a profile of closed shape must be produced from (only) fiber-reinforced plastic. Composite material structures of this kind have inherently low vibratory characteristics.
[0009] In stands for the applications mentioned, however, there exist joints, rotary bearings and the like in which vibratory behavior can occur regardless of the quality of the other components. One such point, for example, is the vertical rotary bearing on a vertical upright column for the horizontal carrier arm or arms of the stand. Proceeding from such bearing points, which as a rule can be immobilized using brakes, movements or forces on the microscope also create torsional forces which in turn can preferentially excite torsional vibrations in the components that are loaded in torsion.
[0010] For particular vibration damping, the present applicant has already offered solutions that are recited, for example, in WO-A-98/53244. In this, inter alia, elastically damping layers which act to damp the vibration chain from the microscope to the floor are installed under the mounting feet of the tripod foot. With these known assemblages, even the slightest change in the position of the microscope causes a vibratory excitation which nevertheless, once it has passed through the stand, is damped at the mounting feet and therefore reflected only in attenuated fashion.
[0011] Damping plates that are inserted between stand components have also been proposed, for example damping shoes at the transition from a support tube to a support tube mount, or damping plates between two flanges of two adjacent support tubes or between a tube and a pedestal.
[0012] The advantage of such damping elements in the region of the upper body of the stand is that they help damp the vibrations on their initial path from the microscope to the floor, so that need not even pass through the entire stand. The effectiveness of these known damping shims lies in the damping effect that occurs upon compression of these damping elements, i.e. for example when the tube vibrates in its shoe in the axial direction of the tube or in a direction perpendicular thereto (tilting vibration), or if the mounting feet are loaded in terms of pressure load fluctuations due to vibration of the upright column in a vertical plane.
[0013] Attempts to damp torsional vibrations have hitherto been made by way of a particular configuration of the support tubes. For example, aluminum/composite plastic tubes or carbon fiber-reinforced plastic tubes have been created, in which torsion in the tube was counteracted by specific selection of the fiber plies. The OHS of the present applicant that is configured in this fashion has low torsional behavior, however, not only as a result of good selection of the supports, but also because of the balanced configuration about the rotation axis in the upright column. In this known assemblage, the center of gravity of the moving carrier arms and balancing arms lies directly above or in the immediate vicinity of the upright column. Other stands in which the center of gravity of the moving carrier arms is well to the side of the upright column amplify the torsional vibration behavior, especially if the stand is braked via the rotation axis. Mere application or release of the brake, or the slightest movements of the microscope, can generate torsional vibrations.
[0014] Torsional vibrations (often horizontal vibrations) are substantially more deleterious in microscopy than vertical vibrations, in particular because in the case of a vertical vibration, the depth of focus that is always present means that a slight vibration is not noticed. Horizontal vibrations, however, result in a severe negative impact when observing through the microscope.
SUMMARY OF THE INVENTION
[0015] It is the object of the present invention to find solutions which improve the vibratory behavior of the stand, i.e. suppress vibration or optimally damp any vibrations, without thereby sacrificing precise positioning accuracy. The intention in particular is to counteract low-frequency torsional vibrations, e.g. in the range of, for example, 0 to 10 Hz. The new features are intended to effectively counteract torsional vibrations and optionally to be usable in combination with known vibration damping features.
[0016] Those skilled in the art know that such objects are difficult to achieve, and that the application of mathematical and physical resources and theories often does not bring the expected results. On the other hand, however, even slight improvements are worth striving for, since they improve convenience for the user and consequently increase operating safety. According to the present invention, this object is achieved by way of the features recited in claim 1.
[0017] The invention thus offers, for the components necessarily present on a stand for a surgical microscope, particularly suitable and tuned damping elements with low weight and improved vibratory behavior. The specifications of stand support parts in terms of their vibratory behavior can be slightly reduced, which in this context can result in cost decreases.
[0018] Further specific embodiments and variants thereof are described and protected in the claims. The properties of the preferred material lie within approximately the following parameters:
Static modulus of elasticity 0.2-3 N/mm2; Dynamic modulus of elasticity 0.5-4 N/mm2; Mechanical dissipation factor 0.1-0.2; Natural frequency of material greater than 5
[0019] Hz, measured in each case on the basis of DIN 53513. The preferred material selected is, by way of example, Sylomer® M12, Sylomer® M25 P14 or Sylomer® P12, Sylomer® P25 P15, or in particular Sylodamp® HD-010-11, HD300/1, HD-030-11, HD-050-21, HD-100-11, HD-150-12, HD-300-10 or 12, but preferably HD-300-1 for the dynamic load range from 0 to 0.3 N/mm 2 .
[0020] The dissipation factor at 8 Hz per ISO 10846-2 should preferably be more than 0.1, in particular more than 0.2, at a strain at fracture per DIN 53455-6.4 of more than 100%, preferably more than 200%, and in particular approximately 300%.
[0021] Such materials are available under the designation SYLODAMP® from Getzner Werkstoffe GmbH, B{umlaut over (ur)}s (Austria).
[0022] Damping materials can also be combined if necessary. Variants with specific shaping of the damping materials also lie within the context of the invention. For example, recesses such as blind holes or the like can be provided in order further to influence the damping characteristics.
[0023] Sandwich constructions of different damping materials can be used, for example, for improved torsional stiffness.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The Figures are described continuously. The Description of Figures and the Parts List constitute a unit that is mutually complemented by the other parts of the Specification and the claims for purposes of a complete disclosure. Identical reference characters denote identical parts. Identical reference characters with different indices denote similar, functionally identical parts. The Figures are exemplary only, and not necessarily depicted in correct proportion. In the Figures:
[0025] [0025]FIG. 1 is an oblique view of a stand rotary bearing according to the present invention, at the transition between the upright column and a carrier arm;
[0026] [0026]FIG. 2 shows a vertical section through the structure of FIG. 1;
[0027] [0027]FIG. 3 shows an enlarged detail of FIG. 2;
[0028] [0028]FIG. 4 shows a variant with a modified position of the damping material; and
[0029] [0029]FIG. 5 shows a sandwich that combines several damping layers;
[0030] [0030]FIG. 6 symbolically depicts another damping element;
[0031] [0031]FIG. 7 shows a variant of the element according to FIG. 6;
[0032] [0032]FIG. 8 shows a variant of a cylindrical damping element arrangement; and
[0033] [0033]FIG. 8 a shows a section, in plan view, of the arrangement according to FIG. 8.
[0034] The Figures are described in overlapping fashion. Identical reference characters denote identical objects; identical reference characters with different indices denote components with identical or similar purposes but a different construction. The Parts List is an integral constituent of the Description of Figures.
DETAILED DESCRIPTION OF THE INVENTION
[0035] [0035]FIG. 1 shows a portion of an implemented configuration of the stand according to the present invention. This configuration is directly linked to U.S. patent application Ser. No. ______ (claiming priority of German patent application 101 23 166.0 filed Mar. 30, 2001), which application was filed on the same date as the present application, shares the same applicant as the present application, is incorporated herein by reference in its entirety, and which deals with another detail of possible stand equipment.
[0036] A bearing sleeve 33 —which preferably, according to aforementioned U.S. patent application Ser. No. ______, can be brought into plumb—that carries a support member 3 is provided on an upright column 1 (merely indicated). Joined to support member 3 is a carrier arm 2 (merely indicated), such as is, for example, labeled 11 c in FIG. 12 of aforementioned U.S. patent application Ser. No. ______. Carrier arm 2 is rotatable about a rotation axis 30 so that it can bring its load (a microscope) into various spatial positions. In order to retain a selected spatial position, a brake 4 is provided which immobilizes carrier arm 2 in the braked state relative to upright column 1 . Once the braked position has been reached, even very small lateral alternating forces on the load (microscope) can result in a vibratory excitation that causes the load to oscillate back and forth. In that context, torsional forces take effect in brake 4 , in stand column 1 , and in the carrier arm itself (as flexural forces). The principal object of the invention is to suppress or compensate for this back-and-forth oscillation as completely as possible. In the configuration shown in FIG. 1, this is brought about by way of a torsional damping element 5 a that is arranged between brake engagement surface 6 and support element 3 .
[0037] Brake 4 substantially comprises a brake body 7 and an armature 8 , as well as an armature flange 9 a . Brake body 7 is nonpositively connected to support element 3 , and armature flange 9 a or armature 8 is nonpositively connected to upright column 1 . The connection to support element 3 is brought about by way of bolts 11 , whereas the connection to upright column 1 is made via bolts 10 .
[0038] Also secured to upright column 1 is a pivot limiter 12 that, in combination with a stand foot of specific configuration and an equipment box (cf. FIG. 12) of aforementioned U.S. patent application Ser. No. ______ serving for weight balancing, results in the inventive effect of Patent Application PCT/EP98/03614 (International Publication No. WO 99/01693) and is to that extent also given protection.
[0039] Pivot limiter 12 coacts with a stop 13 on support element 3 (FIG. 2).
[0040] As is better evident from FIG. 2, upright column 1 comprises a bearing block 14 that carries a bearing 15 in which support element 3 is mounted. Located concentrically inside the support element is an armature bracket 16 that is rigidly joined to bearing block 14 and at its upper end supports armature 8 via armature flange 9 a . Axis 30 of upright column 1 thus constitutes the rotation axis for support element 3 and thus for carrier arm 2 .
[0041] The context of the invention of course also encompasses any other assemblages in which no upright column, or a different upright column, is provided, or in which the function of the upright column is assumed by other components, e.g. in ceiling mounts, the ceiling column; or in wall mounts, the wall retainer; or in stands having multiple carrier arms, one of the latter.
[0042] The manner of operation of brake 4 (which is electromagnetic in this case) and of the assemblage according to the present invention is as follows: when brake 4 and brake body 7 are in the unenergized state, as depicted in FIG. 2, armature 8 rests against brake engagement surface 6 on brake body 7 . No rotation is therefore possible between support element 3 and armature bracket 16 (and therefore upright column 1 ). The braking force is thus transferred from upright column 1 via bearing block 14 into armature bracket 16 , and from there via armature flange 9 a to armature 8 and brake body 7 , then being transferred from the latter via a damping flange 18 to support element 3 and thus to carrier arm 2 .
[0043] Damping flange 18 comprises an upper and a lower flange 17 a, b , between which damping element 5 a is inserted or adhesively bonded. The upper and lower flanges are separated by spacer sleeves 19 that on the one hand make possible a certain preload between the two flanges, but on the other hand also, as a result of a corresponding elongated hole or hole size configuration, also offer a capability of rotation relative to one another about axis 30 .
[0044] Spacer sleeves 19 also prevent torsional damping element 5 a from being loaded in tension when the brake is open. This relieves stress on the adhesive bond if, as is preferred, the torsional damping element is adhesively bonded onto flanges 17 .
[0045] Armature 8 itself is not depicted in further detail, but is spring-loaded as is usual in such brakes.
[0046] The rotation capability about spacer sleeves 19 creates a clearance that allows carrier arm 2 to pivot slightly even when brake 4 is applied. Torsional damping element 5 a counteracts this pivotability with its torsional resilience. In the preferred embodiment, this resilience results in approximately 100% return of a carrier arm 2 moved in the tolerance range. The specific configuration and material selection for torsional damping element 5 a result in the vibration-damping properties of the assemblage.
[0047] The assemblage as shown in FIG. 4, in which torsional damping element 5 b is adhesively bonded between armature 8 and armature flange 9 a , is not substantially different. What is disadvantageous about this assemblage, as compared to the one first described, is the fact that torsional damping element 5 b is loaded in tension when brake 4 is applied (i.e. most of the time), which could be disadvantageous for the bonded surfaces.
[0048] Torsional damping element 5 c depicted in FIG. 5 comprises multiple damping layers 28 made of damping material, and metal washers 27 a and 27 b joined thereto in sandwich fashion. Such sandwich assemblages are usable in the context of the invention as necessary, and the detailed material choice made by the user depends on the particular requirements in terms of the application and damping. Softer or harder damping materials can be used depending on whether the user desires softer or harder resilience characteristics, more or less damping, or more or less play. The damping materials preferred according to the present invention are recited in the specification and in the claims.
[0049] According to a particular embodiment of the invention, the torsional damping element made of a series of different elements is replaceable and/or its preload is adjustable, so that a user can himself select the degree of damping.
[0050] [0050]FIG. 8 shows an assemblage similar to the assemblages described earlier. Armature flange 9 b is differently configured, however, in that it directs a pivot pin 29 downward against an armature follower 26 that concentrically surrounds the latter. A rotational clearance, which is damped by a sleeve-shaped torsional damping element 5 d , is thus possible between armature follower 26 (which assumes some of the functions of armature bracket 16 ) and the pivot pin.
[0051] [0051]FIG. 8 a shows a section through the region of torsional damping element 5 d in the assemblage of FIG. 8.
[0052] [0052]FIGS. 6 and 7 indicate variants of the assemblage shown in FIG. 8, in which there is a departure from the principle of pure shear loading in the torsional damping element, and instead tension-compression components are also used in the particularly configured torsional damping element 5 e , 5 f.
[0053] Torsional damping element 5 f shown in FIG. 7 is an element made up of a polygonal tube that is inserted or adhesively bonded into a congruent cavity between two mutually rotatable parts and is thus loaded on the one hand slightly in shear, and in tension-compression.
[0054] In torsional damping element 5 e shown in FIG. 6, a tubular element is provided between two mutually rotatable parts and is in that respect loaded in shear, while radially projecting lugs 31 engage into counterpart recesses in the mating part and thus can be loaded in tension-compression and can develop their respective individual damping characteristics.
[0055] Parts List
[0056] [0056] 1 Upright column
[0057] [0057] 2 Carrier arm
[0058] [0058] 3 Support member
[0059] [0059] 4 Brake
[0060] [0060] 5 a - f Torsional damping element
[0061] [0061] 6 Brake engagement surface
[0062] [0062] 7 Brake body
[0063] [0063] 8 Armature
[0064] [0064] 9 a, b Armature flange
[0065] [0065] 10 Bolts
[0066] [0066] 11 Bolts
[0067] [0067] 12 Pivot limiter
[0068] [0068] 13 Stop
[0069] [0069] 14 Bearing block
[0070] [0070] 15 Bearing
[0071] [0071] 16 Armature bracket
[0072] [0072] 17 a, b Flange
[0073] [0073] 18 Damping flange
[0074] [0074] 19 Spacer sleeves
[0075] [0075] 26 a, b Armature followers
[0076] [0076] 27 , 27 a, b Metal washers
[0077] [0077] 28 Damping layers
[0078] [0078] 29 Pivot pin
[0079] [0079] 30 Axis
[0080] [0080] 31 Lugs
[0081] [0081] 32
[0082] [0082] 33 Bearing sleeve
[0083] [0083] 34
[0084] [0084] 47 Pivot axis—see aforementioned U.S. patent application Ser. No. ______ (not essential for the present invention). | The invention concerns a novel stand in which at least one support ( 1, 2 ) is torsionally vibration-damped with respect to another ( 2, 1 ). | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of the following U.S. Provisional Patent Applications: Nos. 60/453,411, filed Mar. 10, 2003; 60/463,394, filed Apr. 16, 2003; 60/485,475, filed Jul. 8, 2003; 60/528,256, filed Dec. 9, 2003 and 60/541,781, filed Feb. 4, 2004; all these applications having been filed by Rolf U. Halden and assigned to The Johns Hopkins University.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to measuring and testing of environmental and biological phenomena. More particularly, the present invention relates to methods and apparatuses for environmental monitoring and bioprospecting.
2. Description of Prior Art
Bioremediation is an effective, yet inexpensive biotechnology for removing organic and inorganic pollutants from contaminated environments. When targeting dissolved metals and radionuclides, the goal is to convert water-soluble, toxic species to insoluble, less toxic products. For example, uranium may be removed from contaminated groundwater and immobilized in the subsurface via the injection of carbon sources that stimulate the microbially induced precipitation of dissolved U(VI) in the form of insoluble U(IV). In this case, the contaminant is being treated “in place” and the process is being referred to as in situ bioremediation.
When designing in situ bioremediation strategies, it is essential to gain an understanding of the type, activity, and nutritional requirements of subsurface microbial communities present at a specific cleanup site. Microbial community information also is important for convincing regulatory agencies and stakeholders that the contaminant is being removed (or, in the case of metals, successfully immobilized in the subsurface) rather than being diluted or dispersed in groundwater.
Currently, the assessment of bioremediation potential at a given site is both labor- and cost-intensive. A typical approach for implementing bioremediation includes the following two steps: (1) Microcosm screening studies conducted in the laboratory to determine the extent of intrinsic bioremediation and to identify the type, quantity and frequency of carbon source injection that may be needed in order to accelerate the in situ bioremediation process; these experiments also serve to estimate contaminant removal rates but do not accurately reflect actual in situ removal rates due to the biases introduced by laboratory “bottle effects,” and (2) Microbial community profiles are obtained from microcosm and field samples to determine the microorganisms responsible for the desired biotransformation reactions; since most microorganisms fail to grow on laboratory media, culture-independent profiling techniques are commonly used, (e.g., 16S rDNA-based analyses).
Groundwater is the usual preferred sample matrix for profiling of microbial communities, as it is both readily available and inexpensive. Unfortunately, the lifestyle of a given target organism has a significant impact on one's ability to detect it in this matrix. In the extreme, a target organism pursuing a sessile lifestyle throughout its existence will be impossible to detect in groundwater at a site even if it is present at extremely high densities. Thus, groundwater monitoring alone may not accurately reflect the microbial community composition and dynamics of subsurface environments. Recently, solid-phase samplers were rediscovered as useful tools for overcoming some of these limitations.
In their simplest configuration, solid-phase samplers are nothing more than a physical surface incubated in an environment of interest for a period of time sufficiently long to allow for the colonization by microorganisms. Buried or submerged glass slides have been used extensively to collect microorganisms from soils, bioreactors and other environments. Following retrieval of such samplers, microorganisms are extracted and identified via the detection of biomarkers including DNA, phospholipids, fatty acids and respiratory quinones. An argument can be made that microorganisms collected with a solid-phase sampler are more representative of the metabolically active microbial community than those obtained by groundwater sampling because the sampling device requires the active physical attachment by the microorganisms to be captured. However, dead microorganisms, cell debris and DNA also may become entrapped. Highly sensitive tools (e.g., the polymerase chain reaction, PCR) can detect biomarkers in non-living material as well as those of metabolically active microbial community members.
Recently, stable-isotope markers have been used to distinguish metabolically active microorganisms from those being dormant or non-viable. Stable isotope probing (SIP) exploits the fact that the DNA of an organism growing on carbon-13 enriched carbon sources becomes 13 C-labeled (“heavier”), thereby enabling one to resolve its DNA from the total community DNA by density gradient centrifugation. While representing a powerful research tool, stable isotope probing appears to have limited potential for being applied for routine biological monitoring since the technique is very time- and labor-intensive.
An alternative approach for the identification of microorganisms is to look for gene expression products (i.e., proteins) rather than for their characteristic DNA sequences. This can be done with the latest generation of mass-spectrometry instrumentation that offers sufficient speed and sensitivity, while also allowing for complete automation of the analysis process.
Matrix assisted laser desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS), with its ability to induce desorption of protein biomarkers from intact bacteria, fungi, spores and viruses, provides a powerful and rapidly emerging technology for fast, portable and robust microorganism identification. MALDI-TOF-MS techniques are very rapid (<5 minutes analysis time per sample), have low sample volume requirements (<1 mL) and have a generic capability to identify microorganisms.
Robotic devices recently have been integrated with MALDI-TOF instruments to provide for automation of this analysis technique. The latest generation of commercially available robotics allows for the fully automated sample preparation and analysis, including preparation and imaging of 2D gels, harvesting and digestion of the protein spots, and application of the digests to multi-sample MALDI-TOF targets for analysis.
Despite all the prior art in this field, there still exists an ongoing need for improved testing methods and apparatus. For example, a methodology and technology that could integrate the above technologies so as to provide for both microbial community profiles and microcosm screening studies in a one-step, lower cost process would contribute greatly to this field. Ideally, such a fully developed methodology and technology would yield information on what types of organisms are present, which are alive and metabolically active, what type of nutrients and nutrient dosages should be used to accelerate bioremediation, and what in situ bioremediation rates would result.
Such a new methodology and technology should also prove to be quite valuable in other in situ applications; for example, in bioprospecting in saturated media, i.e., for the discovery of novel microorganisms, biochemical reactions, and natural products. Since less than an estimated one percent of environmental microorganisms are thought to be capable of growing and functioning under laboratory conditions, a new methodology and tool for exploring in situ microbial processes could effectively open the research door to a large fraction of the uncharted microbial world.
The underlying rationale of such an invention would be—since the majority of microorganisms do not tolerate the transfer from their natural habitat to the laboratory—to deliver the laboratory to the microorganisms. The impact of such an invention would be to benefit both human and environmental health by accelerating the discovery of novel microorganisms, enzymes and metabolic processes.
The present inventor has been working in this technical field and towards the development of such an improved methodology for some time. Much of his earlier research is applicable to the methodologies described herein. Most of this work has been documented in the scientific literature. See for example: Franklin, M. P., V. Madrid, S. Gregory, and R. U. Halden, “Spatial Analysis of a Microbial Community Mediating Intrinsic Reductive Dechlorination of TCE to cis-DCE at a DOE Superfund Site,” presented at the 103rd ASM General Meeting, Washington, D.C., May 18-22, 2003; Halden, R. U., B. G. Halden, and D. F. Dwyer, “Removal of dibenzofuran, dibenzo-p-dioxin, and 2-chlorodibenzo-p-dioxin from soils inoculated with Sphingomonas sp. strain RW1.” Appl. Environ. Microbiol., 65:2246-2249 (1999); Halden, R. U., E. G. Peters, B. G. Halden, and D. F. Dwyer, “Transformation of mono- and dichlorinated phenoxybenzoates by phenoxybenzoate-dioxygenase in Pseudomonas pseudoalcaligenes POB310 and a modified diarylether-metabolizing bacterium,” Biotechnol. Bioeng. 69:107-112 (2000); Halden, R. U., S. M. Tepp, B. G. Halden, and D. F. Dwyer, “Degradation of 3-phenoxybenzoic acid in soil by Pseudomonas pseudoalcaligenes POB310(pPOB),” Appl. Environ. Microbiol. 65:3354-3359 (1999); Colquhoun, D., E. S. Wisniewski, D., A. Kalmykov, and R. U. Halden, “Identification of Sphingomonas wittichii RW1 Through the Dioxin Dioxygenase Enzyme Using Mass Spectrometry. 104 th General Meeting of the American Society for Microbiology, New Orleans, La., May 23-27 (2004); Halden, R. U., R. N. Cole, C. Bradford, D. Chen, and K. J. Schwab, “Rapid Detection of Norwalk Virus-like Particles using MALDI-TOF MS and ESI-MS/MS,” 51 st Meeting of the American Society for Mass Spectrometry, Montreal, Quebec, Canada, Jun. 8-12, 2003, http://www.inmerge.com/aspfolder/ASMSSchedule2.asp; Lowe, M., E. L. Madsen, K. Schindler, C. Smith, S. Emrich, F. Robb, and R. U. Halden, “Geochemistry and microbial diversity of a trichloroethene-contaminated Superfund site undergoing intrinsic in situ reductive dechlorination,” FEMS Microbiology Ecology 40:123-134 (2002); Vancheeswaran, S., R. U. Halden, K. J. Williamson, J. D. Ingle, and L. Semprini, “Abiotic and biological transformation of tetraalkoxysilanes and trichloroethene/cis-1,2-dichloroethene cometabolism driven by tetrabutoxysilane-degrading microorganisms,” Environ. Sci. Technol. 33:1077-1085 (1999); and Vancheeswaran, S., S. H. Yu, P. Daley, R. U. Halden, K. J. Williamson, J. D. Ingle, and L. Semprini, “Intrinsic remediation of trichloroethene driven by tetraalkoxysilanes as co-contaminants: results from microcosm and field studies,” Remediation 13/14:7-25 (2003). The teachings and disclosure of these works are hereby incorporated herein by reference.
3. Objects and Advantages
There has been summarized above, rather broadly, the background that is related to the present invention in order that the context of the present invention may be better understood and appreciated. In this regard, it is instructive to also consider the objects and advantages of the present invention.
It is an object of the present invention to provide an improved, lower cost method for environmental monitoring and bioprospecting.
It is another object of the present invention to provide an improved bioremediation assessment method and tool that will more effectively support the environmental restoration and long-term stewardship of contaminated sites. It is yet another object of the present invention to provide an improved bioremediation assessment method and tool that will enable the automated, large-volume, high-throughput analysis of bioremediation sites.
It is a further object of the present invention to provide a monitoring method, tool and analysis strategy that allow for the automated, rapid and simultaneous determination of the following parameters: (1) fluid quality and toxicity, (2) intrinsic bioremediation potential, (3) accelerated bioremediation potential following nutrient amendment, (4) effective bioaugmentation strategies for environmental cleanup, (5) turnover rates of natural compounds and environmental pollutants under natural and enhanced conditions, (6) in situ DNA synthesis and protein expression, (7) in situ growth/death rates and metabolic activity of native and introduced biological agents under natural and altered environmental conditions, (8) structure and dynamics of microbial communities indigenous to natural environments, and (9) identity and activity of microorganisms of potential value for use in biotechnology.
It is an object of the present invention to provide a monitoring method and tool that may be applied to assess the potential risk resulting from the release of nonindigenous microorganisms, pathogens and genetically engineered microorganisms into natural environments.
It is another object of the present invention to provide a method and tool that have potential value for discovering microorganisms, enzymes and natural products of relevance for the pharmaceutical industry and the biotechnology sector.
These and other objects and advantages of the present invention will become readily apparent as the invention is better understood by reference to the accompanying summary, drawings and the detailed description that follows.
SUMMARY OF THE INVENTION
Recognizing the needs for the development of improved methods and apparatuses for environmental monitoring and bioprospecting, the present invention is generally directed to satisfying the needs set forth above and overcoming the disadvantages identified with prior art devices and methods.
In a first preferred embodiment, such a method comprises the steps of: (a) locating a sampling device in an environment to be investigated, wherein this device comprises: (i) a container having a fluid inlet and outlet, (ii) a plurality of capillary microcosms situated within the container, each of these capillaries having an inlet and outlet that are configured so as to allow for fluid flow through the capillaries, each of these capillaries further having a means for covering its inlet and outlet so as to prevent flow through the capillary, (iii) a pump connected to the container inlet, the pump being configured so as to draw fluid from the surrounding environment, following which it is forced into the container's inlet and through the capillaries, (iv) connected to the outlet of the container, a means for collecting the flow forced through the capillaries by the pump, and (v) a check valve connected downstream of the container to prevent the backflow of fluid into the container, this plurality of capillaries being configured so as to allow for automated analysis of the capillaries using commercially available robotics, (b) opening the capillary covering means so as to allow fluid from the surrounding environment to flow though the container and capillaries, (c) leaving the device in situ for a temporal duration termed incubation period sufficient to study phenomena occurring within the capillary microcosms, (d) retrieving the testing device, and (e) analyzing phenomena occurring with the capillary microcosms using real-time sensors, automated analysis schemes and commercially available robotics.
In another preferred embodiment, the present invention takes the form of the method described above plus the step of performing, with the device, a screening study between specified test substances added to the capillaries for their assumed ability to accelerate a specified bioremediation process in the subject environment.
In a still further preferred embodiment, the present invention takes the form of a testing device for environmental monitoring of and bioprospecting for microorganisms within a specified environment. This embodiment comprises: (a) a container having a fluid inlet and outlet, (b) a plurality of capillary microcosms situated within the container, each of the capillaries having a capillary inlet and outlet that are configured so as to allow for fluid flow through the capillaries, each of the capillaries further having a means for covering the capillary inlet and outlet so as to prevent flow through the capillary, (c) a pump connected to the container inlet, the pump being configured so as to draw fluid from the surrounding environment and force it through the container's inlet and the capillaries, (d) connected to the outlet of the container, a means for collecting the flow forced through the capillaries by the pump, and (e) a check valve connected downstream of the container to prevent the backflow of fluid into the container, wherein the plurality of capillaries being configured so as to allow for automated analysis of the capillaries using commercially available robotics.
In yet another preferred embodiment, the present invention takes the form of the testing device described above and wherein the plurality of capillaries are configured so as to aid in the identification of microorganisms indigenous to the environment surrounding in situ location of the container.
Thus, there has been summarized above, rather broadly, the present invention in order that the detailed description that follows may be better understood and appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of any eventual claims to this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of a preferred embodiment of the present invention.
FIG. 2 is a cross-sectional view of the housing shown in FIG. 1 , with enlarged representations of a valve plate adjacent to capillary inlets in both their open and closed positions.
FIG. 3 is an exploded view showing a valve plate of FIG. 1 and the components that are used to cause it to move laterally to open and close the capillary's inlet.
FIG. 4 is a schematic representation of a preferred embodiment of the present invention being extended down a groundwater monitoring well.
FIGS. 5A-5C illustrate the utility of the present invention for microbial community analysis at an uranimum contaminated site. Conventional microbial community analysis produces a picture as shown in FIG. 5A . The present invention allows for the determination of 96 or more community profiles determined under various environmental conditions as shown in FIG. 5B . Environmental conditions in the sampler of the present invention allow for the selective enrichment of pollutant-degrading bacteria; some of these may be detected for the first time, as shown in FIG. 5C .
FIG. 6 shows one possible configuration of a 96-well microtiter plate configured for environmental monitoring and bioprospecting at a hypothetical site containing groundwater contaminated with fuel hydrocarbons from a point source, and dibenzofuran, and the pyrethroid degradate 3-phenoxybenzoic acid (3-POB) from non-point sources.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Before explaining at least one embodiment of the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As previously mentioned, the present invention can serve many purposes, including: the management and bioremediation of contaminated sites, the detection of microorganisms in terrestrial and extra-terrestrial environments, the risk assessment of microorganisms introduced into natural environments, and the search for novel microorganisms, enzymes and/or compounds applicable to biotechnology.
The present invention provides both a monitoring tool and an analysis strategy or method. These allow for the automated, rapid and simultaneous determination of many key bioremediation parameters and the identification of microbial communities indigenous to natural soil and water environments, and the discovery of microorganisms of potential value for use in biotechnology.
The present invention for the first time allows for the cultivation, selective enrichment and comprehensive biochemical characterization of microorganisms in their natural environments. Its technology:
(a) combines the following tools/approaches: solid-phase sampling techniques, in situ enrichment and biochemical screening, use of electron donor/acceptor pairs, isotope labeling and massive parallel screening with automated analysis, (b) makes use of in situ microcosm arrays in conjunction with culture-independent microbial community analysis to obtain a comprehensive picture of microbial communities, (c) can provide data for hundreds or even thousands of hypothetical environmental scenarios, thereby allowing one to determine quickly and in an automated fashion the likely rates of environmental change induced by these perturbations, (d) is suitable for linking specific microbes to observed reactions by using computer-assisted subtractive profiling techniques, (e) is fully compatible with existing robotic systems, thereby allowing for rapid and fully automated analysis using chemical, physical, biological, genomic and proteomic analysis techniques, (f) allows one to determine how non-native microorganisms will cope in natural environments when confronted with physical, biological and/or chemical stressors, (g) can be optimized for exclusive in situ applications, ex situ applications, or a combination of the two, and (h) allows for proteomic approaches to be used for rapid and fully automated analysis (e.g., matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and protein sequencing of enzymatic digests using tandem mass spectrometry (MS/MS)).
One embodiment of the present invention takes the form of an in situ microcosm array (ISMA) sampler or testing device 1 . As shown in FIGS. 1-4 , its principal components include: a housing or container 10 having a fluid inlet 12 and outlet 14 , a plurality of capillary microcosms 16 situated within this housing, with these capillaries 16 making up what is referred to as a microcosm array, each of these capillaries 16 having an inlet 18 and outlet 20 that are configured so as to allow for fluid flow through the capillaries 16 , each of these capillaries contains a filtration material 22 that is selected for its ability to foster microorganism collection in the individual capillaries, upper 24 and lower 26 valve plates having openings 28 that are configured to be alignable with the capillary inlets 18 and outlets 20 , a pneumatic cylinder 30 with coupling means 32 and an assortment of springs 34 serves to enable these valves to be moved laterally so as to open or close the capillaries' inlets 18 and outlets 20 , gasketing pads 36 , 38 serve to prevent leakage from these openings, a pump 40 is connected to the container's inlet 14 and is sized so that it can draw fluid from the environment surrounding the container 16 and push it through the container's inlet 12 and through the capillaries 16 , a collecting device or a bladder 42 is connected to the pump's outlet and is used to collect the flow through the container 16 , a check valve 44 connected between the pump 40 and bladder 42 prevents backflow of fluid through the container 16 , a weight 46 serves to provide ballast for suspending via an umbilical cable 48 the sampler 1 down a suitably drilled well that extends into the region of interest.
The initial ISMA prototype samplers of the present invention were based on commercially available 96-position (8×12) microtiter plate format (e.g., Wheaton Scientific Products); similar 384, 1536 (or more) plate formats could have been used. Each well or “microenvironment” of the initial prototype samplers consisted of a Teflon block with 96 drill holes representing individual microcosm capillaries (1.12 mL; 0.295 inch [diameter]×1 inch [length]).
The inclusion into the ISMA sampler 1 of a pump 40 , closure mechanism valve plates 24 , 26 , and semi-permeable membranes allows one to first inoculate and then incubate the device in the environment without removing (and potentially harming) the resident microbes from their natural environment. Pump configurations other than those shown in the drawings include, but are not limited to, multi-channel pumps and pump arrays that deliver fluids to the inlet of one or more individual microcosm capillaries.
The ISMA sampler 1 of the present invention can be equipped with a collecting device or a bladder 42 . Fluid flowing through the array exits the container and is collected in the bladder. Displacement of air from the collection device may be desirable, and can be achieved by inclusion in the collection device of a bleed valve allowing air to escape via a piece of tubing rising along the umbilical cable to a location some distance above the fluid intake.
As the fluid flows through the device, microorganisms and chemicals can be trapped in the capillary microcosms 16 . When the collection device is full, a float can trip power to the pump and actuate the valve plates 24 , 26 of the closure mechanism, thereby sealing the array. Immediately, or after an additional incubation period in batch mode, the device 1 can be removed from the environment for further analysis.
The ISMA sampler 1 of the present invention can be designed for reuse. For this purpose, the invention can be equipped with a means allowing for rapid exchange of microtiter plates.
Exchangeable microtiter plates can be manufactured to allow for long-term storage prior to use. For this purpose, the content of customized microtiter plates can be lyophilized and vacuum sealed. Breaking of the vacuum and rehydration of the microtiter content will ready the device for testing. Microtiter contents include, but are not limited to, a means for containing a specified test substance, a test compound, and a test organelle or microorganism.
The ISMA sampler 1 of the present invention can be equipped with a means for capturing microorganisms and chemicals of interest. Such a means can be chosen from the group comprised of sorption, precipitation, sedimentation, coagulation, filtration, straining, extraction, chromatography, affinity separation, size exclusion separation, passive attachment to presented surfaces, and active attachment to presented surfaces.
The ISMA sampler 1 of the present invention can be equipped with microfluidic systems allowing for delivery of small liquid volumes and defined quantities of organelles to the test chamber prior to physical and/or chemical containment of the captured specimens via barriers that are either non-permeable, semi-permeable or completely permeable for chemical compounds. This aspect allows one, for example, to culture uncultivated or “non-culturable” bacteria to numbers sufficiently large to perform biochemical characterization and identification.
This sampler also may be adapted for studying the fate of either beneficial or hazardous chemical agents in natural environments. In this application, the sampler 1 is modified to reflect as closely as possible within each test compartment or microcosm the physical, chemical and biological environment of interest (e.g., flow-through cells equipped with local sediment etc.). Test chemicals are included in the sampler prior to its deployment and diffuse from within the sampler into the ambient fluid. Following interaction with the local environment, all chemicals are captured in the bladder.
This sampler also may be adapted for studying the fate of either beneficial or hazardous biological agents in natural environments. In this application, the sampler 1 is modified to reflect as closely as possible within each test compartment or microcosm the physical, chemical and biological environment of interest (e.g., flow-through cells equipped with local sediment etc.). Test organisms are inoculated into the sampler prior to its deployment and the sampler is incubated in situ allowing for interaction of the test organisms or species with the environment without allowing for its release.
Modification of the sampler's closure valve plates 24 , 26 allows for sequential opening and closing of its microcosm compartments. Real-time and monitoring equipment (pH, Eh, temperature, DO, etc.) can be added to the sampler 1 to increase functionality and to trigger reactions at specific points in time selected by changes in the target environment (e.g., heavy rainfall events). Use of radio frequency signaling and remote controls can replace the standard umbilical cord 48 that is used to communicate with the sampler 1 , and to determine the chemical change occurring during incubation.
It should be noted that the design of the device can be altered to allow deployment of the device in environments featuring extreme conditions including, but not limited to, extreme pH, temperature, pressure, radiation, gravity conditions different from that of planet Earth, etc. Additionally, many types of microfluidics, filters, sorbent materials, semi-permeable membranes and alternative closure mechanisms may be integrated into the sampler to separate in time its inoculation from the incubation period that allows chemical change to take place within the sampler 1 .
It should further be noted that the method and device can be used for bioprospecting and environmental monitoring in any fluid-containing environment including, but not limited to, subsurface environments, surface environments, saturated environments in space, and macroorganisms dead or alive.
Optical and/or electrical detection systems may be incorporated in the microfluidic configurations of the sampler 1 to seal individual microcosms as soon as a single cell has been delivered to the microcosms, thereby greatly increasing the success rate of isolating novel microorganisms.
For example, optical sensors detecting the entry of individual microorganisms into the device, can trigger translation of the valve plates to move from the “open” position into the “closed” position. Different surfaces can be presented in the “closed” position. If the presented surface is impermeable to the microorganism and the flow of water, complete confinement is achieved. If the presented surface is a semi-permeable membrane, water can continue to flow through the device whereas the microorganism is held in confinement.
The present invention's approach for the identification of microorganisms involves looking for gene expression products (i.e., proteins) as well as for their characteristic DNA sequences. For example, ribosomal proteins are used as biomarkers to identify microorganisms by MALDI TOF MS.
For the rapid automated detection of specific microorganisms by MALDI TOF MS, individual microcosms can be configured to support only the growth of specific microorganisms. This is achieved by including in the microcosm chemicals that foster the growth of the target microorganism while suppressing the growth and survival of non-target microorganisms. For example, a combination of selective substrates and antibiotics can serve for this purpose. This type of selective culturing, a common strategy in the microbiology laboratory, is now being performed in situ. By doing so, growth of specific microorganisms and expression of key biomolecules can be achieved. Selective in situ culturing of specific microorganisms then allows for direct detection and identification of these biological agents by mass spectrometry. It makes unnecessary the need for extensive sample preparation and cleanup because of the enhanced signal-to-noise characteristics of the enriched sample.
This in situ cultivation technique can also be used to determine the metabolic and catabolic activity of microorganisms in situ. For this purpose, the presented chemicals can contain isotopic labels such as isotopes of carbon-12 (e.g., 13 C, 14 C).
Use of the invention in conjunction with SIP and nonculture-dependent microbial community profiling tools is another important application.
The advantages of this process are illustrated in FIGS. 5A-5C as applied to the bioremediation of saturated subsurface environments containing uranimum. Conventional microbial community analysis produces a picture as shown in FIG. 5A ; the technique detects the presence of all bacteria; however, it does not provide information on their metabolic activity. The use of isotope-labeled nutrients can reveal which of the detected microorganisms are metabolically active (right half of the community shown in FIG. 5A ).
Use of the ISMA sampler 1 allows for the determination of 96 or more community profiles determined under various environmental conditions (e.g., a screening study in which uranium is being presented at various concentrations), see FIG. 5B . Computational analysis of the resulting data using subtractive community profiling allows one to identify important pollutant-transforming microorganisms within the large group of active microorganisms (not all metabolically active bacteria are partaking in the bioremediation process).
Environmental conditions in the sampler allow for the selective enrichment of pollutant-degrading bacteria; some of these may be detected for the first time, see FIG. 5C . Under appropriate conditions, a poorly represented population may be enriched to a level allowing for MALDI TOF MS-based detection/identification.
To discern which of the potentially relevant microorganisms detectable at a given site are performing a desired reaction, SIP methods may be used. Stable isotopes are used as chemical reporters to help to discriminate metabolically active bacteria from dormant or dead community members and from those performing functions unrelated to desired bioremediation or biostimulation.
Isotope labeled substrates (e.g., 13 C-labeled acetate) may be used as chemical reporters of biotransformation activity in a miniaturized, field-deployable, down-well ISMA. As previously mentioned, each of these devices holds different, physically separated test environments, “test wells” or capillary microcosms.
The method of the present invention begins with placing a suitably configured ISMA in the environment to be examined (e.g., a contaminated, underground site which is accessed by a monitoring well). Once the ISMA has been lowered into a monitoring well to the desired depth, it is triggered from the surface via an electrical signal conducted by a wire (or via other means such as a programmed build-in mechanism). Triggering of the device exposes each of the “test wells” to the flow of groundwater. Microorganisms suspended in the groundwater attach themselves to the presented surfaces and become trapped in the device. Additional free-living microbes become trapped once the device receives the signal to close again.
Some of the test wells may include the contaminant of concern. Individual test wells may also contain, as previously mentioned, one stable-isotope labeled nutrient for determining its effect on microbial growth and activity. The now closed device is incubated in situ to allow for growth of microorganisms on the labeled substrates.
During this incubation period, all bacteria directly or indirectly involved in the utilization of isotope-labeled electron donors become enriched in isotope-labeled DNA. Following retrieval of the tool from the well, microorganisms are collected from the device and their isotope-labeled, higher-density DNA is separated from background DNA by density-gradient centrifugation. This higher-density DNA (and the non-labeled DNA) is then analyzed using known molecular techniques.
Oligonucleotide microarrays serve to identify/enumerate target-specific organisms whereas clone libraries may be used to identify novel, uncultured microorganisms. The device may, ideally, be used in conjunction with commercially available robotics for automated extraction of DNA.
The extent of microbially induced corrosion of metals/radionucliudes may be measured optically by scanning a metal surface placed within the ISMA with a laser; alternatively, contaminant biotransformation may be detected biochemically via addition of a dye/reporter or electrochemically via measurement of electrical resistance. Measurements can be performed real time in situ or post-deployment via analysis of the capillary content, the bladder content, and sorbent materials that were integrated in the device and had an opportunity to chemically interact with fluid drawn into the device.
If uranium is the contaminant of concern, analysis of an uranium-coated surface allows for determining the extent of uranium reduction and the calculation of pollutant removal rates occurring under in situ conditions.
As previously mentioned, test wells of the device also may be equipped with a matrix allowing for the slow, continuous release of chemicals (e.g., external carbon and energy sources; other nutrients; conditioning agents such as pH or redox agents). The matrix may be a polymer or a membrane vesicle containing the nutrient in question. Diffusion characteristics of the matrix/membrane are selected to achieve different nutrient levels in each of the test wells if desired. Presented nutrients may be added in solid, liquid or gaseous state. Energy sources may be presented in the presence and absence of pollutant coating.
Some of the test wells may be configured for continuous flow-through operation in situ. Flow through the device may be passive or active. In active devices, a small pump 40 facilitates groundwater movement whereas tubing of various length and configuration is used to prevent the effluent of one test well from becoming the influent of another.
FIG. 6 shows one possible configuration of a 96-well microtiter plate configured for environmental monitoring and bioprospecting at a hypothetical site containing groundwater contaminated with fuel hydrocarbons from a point source, and dibenzofuran, and the pyrethroid degradate 3-phenoxybenzoic acid (3-POB) from non-point sources. The 96 microcosm capillaries are aligned in parallel in 12 columns (“A” through “L”) and 8 rows (“i” through “viii”). In the microtiter plate customized for this site, all capillaries contain a webbing material for capturing microorganisms. Near the inlet in the front half of each microcosm capillary, the webbing material contains noble agar beads serving as an inert diffusive matrix. Near the outlet in the back half of each microcosm capillary, the webbing material contains sorbent beads to which contaminants can sorb. Capillary Ai does not contain any test substances or microorganisms. When the ISMA is deployed in flow-through mode in the contaminated aquifer, chemical conditions reported for microcosm Ai by real-time sensors are reflective of ambient groundwater quality. Similarly, chemical analysis of the sorbent beads contained in microcosm Ai will yield a time-integrated measure of the contaminant mass that passed through the microcosm during deployment in local groundwater. Following capture of microorganisms in the ISMA during flow-through mode, the valve plates are translated to close the device. Real-time sensing data for microcosm Ai, now incubated in batch mode, will inform on the kinetics of pollutant degradation under ambient conditions (intrinsic bioremediation rate; loss of contaminants as a function of time).
If the groundwater passing through microcosm Ai is anaerobic (ISMA Deployment Location 1; immediately downgradient of the leaking fuel tank), biodegradation of fuel hydrocarbons will be slow and incomplete. In order to accelerate the biodegradation process, a number of electron acceptors can be considered. Rapid, simultaneous screening of common electron acceptor compounds is achieved within the ISMA in microcosms in row “i” (Bi through Ii). Individual electron acceptor compounds presented in these microcosms reflect a redox gradient ranging from highly oxidizing to more reducing conditions: Bi, oxygen releasing formulation (a); Ci, nitrate (b); Di, nitrite (c); Ei, manganese oxide (MnO 2 ) (d); Fi, iron (Fe (III) ) (e); Gi, uranium (U (VI) ) (f); Hi, chromium (Cr (VI) ) (g); and Ii, sulfate (h). By incubating the ISMA in batch mode with these electron acceptors present in excess concentrations relative to the contaminants, real-time sensors from microcosms Bi through Ii will directly report on the results of this screening study of biodegradation of fuel hydrocarbons under a variety of redox conditions. Once the optimal redox conditions have been identified, it is of interest to determine what dosage is needed. Assuming that pollutant turnover was most rapid in the microcosm Bi containing oxygen-releasing formulation (a), the optimal dosage of this “nutrient” can be inferred by comparing the degradation rates obtained in microcosms containing 5-fold (Ji), 10-fold (Ki), and 50-fold (Li) higher levels of oxygen-releasing formulation relative to microcosm Bi. Thus, data obtained with the top row of microcosms already has yielded estimates of intrinsic and enhanced biodegradation rates, and resulted in the identification of the most favorable redox conditions, as well as the optimal dosage of electron acceptors. Other nutrients and conditions can be screened in a similar fashion.
The effectiveness of chemical treatment for the cleanup of groundwater at the fuel spill site is investigated using second-row microcosms Aii through Fii. The removal of hydrocarbons by Fenton's reagent (m) and potassium permanganate (n) is evaluated. In the configuration shown, microcosm Aii and Bii are covered with an inert membrane filter that allows liquid to flow through the capillaries whereas the entry of microorganisms is prevented. Sequential incubation of these microcosms in flow-through and batch mode allows for a direct in situ comparison of the two oxidation agents or chemical treatment strategies. Microcosms Cii and Dii are not sealed with an inert membrane but are otherwise identical to Aii and Dii, respectively. Direct comparison of chemical data from these two pairs of microcosms allows one to evaluate whether biotransformation and chemical oxidation processes can occur simultaneously.
For site assessment purposes, identical ISMA samplers will be deployed at various locations at a given site. For the hypothetical site discussed here, Deployment Location 2 is far downgradient of the release site, outside of the hydrocarbon contaminant plume. In this location, groundwater is expected to be aerobic and will contain only contaminants from non-point sources. In this case, these are represented by 3-phenoxybenzoic acid and dibenzofuran.
Seeding of the ISMA sampler with viable microorganisms (hydrated or lyophilized) is useful for evaluating bioaugmentation and environmental risk assessment of pathogenic and non-pathogenic microorganisms. The customized ISMA sampler considered here, has been seeded with 10 million microorganisms of a particular kind per microcosm (Eii through Hii): Eii, Escherichia coli O157:H7, a pathogen (o); Fii, Sphingomonas wittichii RW1, a dibenzofuran-degrading bacterium (p); Gii, Pseudomonas pseudoalcaligenes strain POB310, a 3-phenoxybenzoate-degrading microorganism (q); and Hii, Pseudomonas sp. strain B13-D5, a genetically engineered microorganism (r) specifically designed to degrade 3-phenoxybenzoic acid rapidly and completely.
One way of evaluating the survival of these microbes in the target environment, is to enumerate culturable cells following deployment, incubation, and retrieval of the ISMA sampler. The effect of environmental conditions on the survival of seeded microorganisms can be evaluated by comparing microbial counts obtained for identical microcosms incubated in different locations, e.g. the survivability of the pathogenic E. coli strain at Deployment Locations 1 and 2 can be assessed by comparing the two viable counts obtained for microcosm Eii.
Strain RW1 is a naturally occurring bacterium capable of utilizing dibenzofuran as a carbon and energy source. Its detection in the dibenzofuran-contaminated aquifer could indicate an intrinsic bioremediation potential for this chemical at the site. One detection technique for the microorganism is the use of strain-specific PCR primers and probes. Alternatively, the bacterium can be detected by mass spectrometry. However, if strain RW1 is present in site groundwater, its environmental density will be orders of magnitude lower than required for this task. The ISMA compartment Iii is configured to overcome this limitation. Microcosm Iii contains the selective substrate dibenzofuran (s). During in situ incubation of microcosm Iii in batch mode in aerobic groundwater, strain RW1 is allowed to increase in density from non-detectable to detectable levels by growing at the expense of dibenzofuran. The presence of dibenzofuran serves two purposes. First, it allows the target bacterium (RW1) to grow to levels sufficiently high for detection by mass spectrometry (>10^7 cells total per microcosm); second, it increases the expression of dioxin dioxygenase, a characteristic enzyme serving as the target for mass spectrometric identification of RW1. The combined effect of in situ growth of RW1 and induction of high levels of dioxin dioxygenase in cells of RW1 is an enhanced signal-to-noise ratio during mass spectrometric analysis (in situ biomarker amplification): levels of dioxin dioxygenase are high relative to the background of non-target proteins contained in the mixture of environmental microorganisms.
Under starvation conditions, microorganisms may divide several times to form ultra-microbacteria; in these instances, viable cell counts indicate bacterial growth (proliferation) whereas, in actuality, the local bacterial population is on the brink of extinction. The ISMA can assist in distinguishing between true microbial growth and the starvation effect described above. This goal is achieved with microcosm Jii that contains the microorganism RW1 (p) and a stable isotope labeled ( 13 C-containing) analog of dibenzofuran (S). Following incubation of the microcosm in situ, its content can be analyzed by mass spectrometry. Successful in situ growth of strain RW1 will be revealed by the detection of a mixture of light (non-labeled) and heavy (isotope-labeled) peptides of the dioxin dioxygenase; the ratio of heavy isotopes-to-low isotopes detected by mass spectrometry informs about the rate of 13 C-dibenzofuran uptake in situ, a measurement that cannot be obtained in field tests because the massive injection of isotope-labeled compounds is cost-prohibitive and faces regulatory obstacles.
Microcosm Kii can be used to illustrate the benefit of data normalization achievable by incorporation of standard microcosms into the ISMA sampler. Microcosm Kii is identical to Jii but sealed with an inert semi-permeable membrane that excludes the entry of indigenous groundwater microorganisms. This microcosm can serve as a benchmark for metabolic activity at the sampling location. For example, when ISMA samplers are deployed year-round in the shallow aquifer of Deployment Location 2, the turnover of 13 C-dibenzofuran and assimilation of 13 C will undergo seasonal fluctuation as a result of subtle changes in water temperature. The direct comparison of datasets obtained with identically configured ISMAs deployed at different points in space and time can be achieved via normalizing the results using the readouts from standard microcosms such as Kii. By doing so, results for the microcosms in row “i” obtained over the course of the year may collapse into a single value. If they do not, this may indicate a relative loss of hydrocarbon degradatation activity in the aquifer.
Following deployment and retrieval of the ISMA sampler, the microbial community of each capillary microcosm can be analyzed using culture-independent techniques such as DNA extraction, amplification of the 16S RNA genes, separation of amplification products by denaturing gradient gel electrophoresis (DGGE), and sequencing of bands followed by phylogenetic sequence analysis. Linking microbial function and phylogeny is an important goal. Subtractive community profiling, i.e., eliminating irrelevant information from large datasets by subtracting multiple datasets from each other, represents one possible way of identifying within a large number of microorganisms the ones that are responsible for a biochemical process of interest ( FIG. 5A-C ).
Another approach to achieve this goal is the use of stable isotope probing. The ISMA technology greatly enhances the utility of this technique for three reasons. One, it facilitates inexpensive SIP analysis by minimizing the volume of liquid required to be spiked with expensive isotope labeled compounds. Two, it allows for batch incubation which increases the labeling efficiency dramatically when compared to labeling in open systems. Three, it avoids the regulatory hurdles associated with injecting isotope-labeled compounds into target environments during field tests.
The utility of the ISMA technology for use with SIP is illustrated by microcosm Aiii and Biii. Microcosm Aiii is identical to microcosm Iii except for the fact that the dibenzofuran contained therein is labeled with 13 C. Following use of the ISMA sampler in Deployment Location 2, culture-independent microbial community analysis of microcosm Iii will yield a large number of DNA sequences some of which may correspond to naturally occurring dibenzofuran-degrading microorganisms. These cannot easily be distinguished from the large background of other bacteria, however. Analysis of microcosm Aiii by SIP will aid in their identification. Following in situ deployment of the ISMA sampler, DNA is being extracted from microcosm Aiii. The obtained DNA is spun in a cesium chloride density gradient to separate 12 C-DNA from 13 C-DNA. Analysis of 13 C-DNA by PCR, DGGE and DNA sequencing will reveal the identity of microorganisms involved in the turnover of dibenzofuran.
Assuming that a sequence corresponding to a single 13 C-labeled microorganism is detected, and that its DNA sequence information is different from that of RW1, then a novel microorganism capable of metabolizing dibenzofuran has been discovered with the ISMA technology. If the 13 C-labeled metabolites detectable in microcosm Aiii are different from those reported for strain RW1, then a novel biochemical process has been detected, whereas the metabolite itself may represent a novel natural product of potential commercial value. Similarly, detection of significant fungal growth in microcosm Biii (containing 13 C-labeled sucrose; T) and concurrent lack of detection of 13 C-labeled DNA corresponding to Gram-positive bacteria can reveal the presence of a fungal natural product suitable for the treatment of Gram-positive infections in animals and humans.
Replicates of individual test systems can be distributed randomly within the 12×8 microtiter format. Analysis of replicate systems informs about the precision of the experimental data obtained. Replicates shown in FIG. 6 include: for Ai-Ciii to Liii, for row i-rows iv, vi and viii, for row ii-rows v and vii.
The test systems disclosed herein will report on intrinsic (bioremediation) biocorrosion potential and rates. Computational analysis of the resultant data sets using subtractive profiling adds a hitherto unattained discriminatory power to the analysis of both microbial community composition and function in subsurface environments.
The technology of the present invention uses various proven techniques and technologies in a novel and non-obvious way to achieve the desired goal: the rapid automated analysis of field samples for microbial community composition, degradative potential, and degradative activity under prevalent conditions and under those conditions that may be created in situ to accelerate the bioremediation process. Techniques/technologies incorporated in the present invention include:
1) Down-well tools for sampling for monitoring wells 2) Microtiter-plate testing and fully automated analysis 3) Slow-release compounds for continuous release of microbial nutrients 4) Membrane technology for delivery of nutrients 5) Micro fluidics 6) Laser detection of microbially-induced corrosion 7) Automated DNA extraction 8) Isotope labeling of microorganisms 9) Density gradient analysis for separation of high-density labeled DNA 10) Microbial community analysis using microarrays and bioinformatics 11) Subtractive community profiling for identification of relevant microorganisms 12) Sorbent materials that can be analyzed to determine the chemical composition of fluid in the individual test compartments.
The usefulness of the present invention's analytical methods can be further aided by: (a) development of mass spectrometric techniques for the identification of microorganisms in mixed cultures, and (b) the generation of microorganism-identification database software and search algorithms for interpreting MALDI TOF mass spectra of ribosomal biomarkers and microorganisms.
Speed and ease of analysis for the present invention is achieved by replacing molecular-genetic analyses with other more convenient measurement techniques suitable for discerning isotope distributions (e.g., use of MALDI-TOF MS and bioinformatics database searches for automated microorganism identification). Sample processing uses commercially available robotics (e.g., Amersham Biosciences robotics) and tools for rapid sample cleanup and processing (e.g., Gyrolab MALDI SP1 etc.) in conjunction with enzymatic digestion steps (e.g., trypsin digestion).
Central laboratory facilities are recommended for analyzing samplers deployed in situ. This allows for automated analysis and for a high degree of standardization. Standardized analysis in turn improves measurement precision and allows one to determine the systematic biases of the technique (due to “bottle effects”) that may limit measurement accuracy. Once identified, these biases can be accounted and corrected for thus enabling one to predict—with high accuracy and precision—the environmental change to be observed following engineering interventions.
Proof-of-concept experiments with components of the testing device of the present invention have demonstrated that:
1. Informative microbial community data can be obtained with nonculture-dependent tools using analysis of conventional groundwater samples and bioremediation microcosms.
2. The screening of electron acceptors and donors in microcosms adds discriminatory/predictive power for microbial community profiling.
3 Integration of stable isotope-labeled electron donor compounds into the microcosm design aids in the identification of metabolically active microorganisms.
4. Adaptations of mass spectrometric analysis of microorganism-specific proteins can be used to identify microorganisms in environmental mixed cultures directly without the need for time and labor intensive separation techniques.
5. Adaptation of microorganism-identification algorithms contained in the existing protein-identification database software allows for the analysis of mixed cultures.
Although the foregoing disclosure relates to preferred embodiments of the invention, it is understood that these details have been given for the purposes of clarification only. Various changes and modifications of the invention will be apparent, to one having ordinary skill in the art, without departing from the spirit and scope of the invention. | A method for environmental monitoring and bioprospecting includes the steps of: (a) utilizing a testing device having: (i) a container having a fluid inlet and outlet, (ii) a plurality of capillary microcosms situated within the container, each of these capillaries having an inlet and outlet that are configured so as to allow for fluid flow through the capillaries, each of these capillaries further having a means for covering its inlet and outlet so as to prevent flow through the capillary, (iii) a pump connected to the container outlet, the pump being configured so as to draw fluid from the surrounding environment into the container's inlet and through the capillaries, (iv) connected to the outlet of the container, a means for collecting the flow through the container, and (v) a check valve connected downstream of the container to prevent the backflow of fluid into the container, (b) adding specified test substances to the device's capillaries, wherein these substances are to be analyzed for their ability to accelerate a specified biotransformation process in the subject environment, (c) locating this device in this environment and opening the capillary covering means so as to allow fluid from the surrounding environment to flow though the container and capillaries, (d) leaving the device in situ for a temporal duration sufficient to incubate phenomena occurring within the capillary microcosms, (e) retrieving the testing device, and (f) analyzing phenomena occurring with the capillary microcosms using automated analysis schemes and commercially available robotics. | 2 |
FIELD OF THE INVENTION
The present invention relates to a coaxial transistor structure, particularly to high-integration coaxial MOSFETs and a full-symmetric coaxial complementary MOSFET formed of the coaxial MOSFETs.
BACKGROUND OF THE INVENTION
The term “transistor” is derived from “transfer-resistor”, which means “varying resistor” or “adjustable resistor”. In electronics, the transistor plays an unparalleled role. The bipolar junction transistor (BJT) varies the built-in resistor to regulate current. In digital logic electronics, the unipolar transistor maximizes the built-in resistor to turn off current or minimizes the built-in resistor to conduct current, such as JFET (Junction-Field-Effect-Transistor), MESFET (Metal-Semiconductor-Field-Effect-Transistor), and MOSFET (Metal-Oxide-Semiconductor-Field-Effect-Transistor). The ability, that control the adjustment of built-in resistor in transistor, is based on the forward bias or reverse bias that both arranged and selected initially of the built-in potential created by the PN junction within structures. In BJT consisting of an emitter, a base and a collector, the bias of the base controls the resistance value of the resistor. In FET consisting of a source(S), a gate(G) and a drain(D), the bias of the gate controls the conduction state of carriers (electrons or holes). In MOS developed afterward, a body(B) is added to FET to prevent from floating potential, and a four-electrode transistor is thus formed. The base or gate functions exactly like a faucet switching on/off water and regulating the flow rate of water.
In fabricating each electrode of the three-electrode or four-electrode transistor, a diffusion, deposition, ion-implanting or epitaxial process forms patterns of cuboids having width, length and depth. The junctions of the electrodes are parallel arranged top-down or from left to right. Thus, the configuration of transistor elements in IC appears like a mosaic pattern, as shown in FIG. 1A and FIG. 1B . FIG. 1A is a top view schematically showing a CMOS inverter, and FIG. 1B is a sectional view of the CMOS inverter shown in FIG. 1A .
In 1947, Shockley, Bardeen and Brattain of the Bell Laboratory invented the transistor, which is a point contact germanium junction transistor and was disclosed in a U.S. Pat. No. 2,569,347 “Circuit Element Utilizing Semiconductive Material” issued on Sep. 25, 1951. However, in early 1960s, the idea of integrating a plurality of transistors into a substrate to miniaturize the digital computer was regarded as an extremely ridiculous thought by the Bell Laboratory—the birthplace of transistors. From then on, microelectronics has advanced by leaps and bounds. From nowadays view, the “humor” of the Bell Laboratory seems to be the motive force of the researchers challenging the miss impossible.
The conventional BJT has advantages of fast response and high current density and extensively applies to analog circuits. In applications to the inverters of digital logic circuits, TTL (Transistor-Transistor Logic) circuits and ECL (Emitter-Coupled Logic) circuits, the conventional BJT is hard to parallel FET, which uses voltage of electric field to control the conduction state, in the integration. Limited by the electrode areas, the conventional BJT is harder to promote the integration. As BJT uses the base current to control the collector-emitter current, the base layer has to physically exist to function as the carrier exchange body no matter how thin it is. The gate of FET is moved to the upper space and uses voltage to control the conduction state of the source-drain current. Thus, FET outperforms BJT in IC integration. Among FETs, MOSFET (MOS for short) has further higher integration, further lower power consumption, further greater input impedance and further smaller input current and thus becomes the most popular element in digital logic circuits. The electron mobility of the N-channel MOS (NMOS for short) is much greater than the hole mobility of the P-channel MOS (PMOS for short). Under the conditions of identical dopant concentrations and identical width-length ratios of the gates, NMOS operates much faster than PMOS. After the appearance of the ion implant technology for a high N-type dopant concentration and a high-precision doping-profile control, NMOS has replaced PMOS.
Refer to FIG. 1A and FIG. 1B . A conventional PMOS 103 and a conventional NMOS 101 are cascaded to form a conventional CMOSFET (Complementary MOSFET, CMOS for short). Two gates of NMOS 101 and PMOS 103 are connected to form a signal input terminal 102 of the digital logic circuit. The cascaded drain and source is used as a signal output terminal 104 . NMOS 101 and PMOS 103 are respectively connected to a high voltage level 105 VDD and a low voltage level 106 Vss—dual-state logic signals. When the common gate inputs a high voltage or a low voltage, one channel of NMOS 101 and PMOS 103 turns on, and the other channel turns off. In other words, whether the input signal is of a high voltage or a low voltage determines the output terminal of the CMOS. Theoretically, CMOS has none static power consumption. Only in the transient moment that PMOS and NMOS exchange the conduction states and turn on simultaneously, CMOS has dynamic power consumption. Since 1980s, CMOS has be used as the low-power consumption and fast-operation transistor structure for digital logic circuits and contributed much to the electronic industry. The conventional CMOS is formed via cascading NMOS and PMOS. No matter whether CMOS has a single well structure or a double well structure, CMOS intrinsically has a parasitic PNPN thyristor structure, which may generate a latch-up effect and make CMOS temporarily or eternally lose the voltage control function or even cause abrupt current increase and circuit burnout.
Refer to FIG. 2A and FIG. 2B for a latch-up state of an N-well CMOS inverter. FIG. 2A is a sectional view of an N-well CMOS. FIG. 2B is a diagram of an equivalent circuit of the CMOS shown in FIG. 2A . Q⊥ denotes a vertical parasitic PNP bipolar transistor, which is formed of a P+ source, an N-type well and a P-type substrate of PMOS. Q∥ is a horizontal parasitic NPN bipolar transistor, which is formed of an N+ source, a P-type substrate and an N-type well of NMOS. The collector of the horizontal NPN is connected to the base of the vertical PNP via the N-type well. The collector of the vertical PNP is connected to the base of the horizontal NPN via the P-type substrate. Then, the P-type substrate functions as the base (of NPN), the collector (of PNP), and the connection medium between the NPN base and the PNP collector; the N-type well functions as the base (of PNP), the collector (of NPN), and the connection medium between the PNP base and the NPN collector. Thus, the P-type substrate and the N-type well (functions like a substrate) become the repeated both collectors and bases (using the same carrier source), which are the origin of the latch-up phenomenon. The thorough solution to exterminate the latch-up phenomenon is to separate the N-type well from the P-type substrate. Rw is the cascade resistor between the N-type well and the P+ source of PMOS and thus called the N-type well resistor. Rsub is the cascade resistor between the P-type substrate and the N+ drain of NMOS and is thus called the substrate resistor. At some instant, a voltage surge caused by turning on a power source, an ionization event or another transient state results in so high a current that flows through the NPN collector and causes the current flowing through the N-type well resistor to bias the base and emitter of the PNP bipolar transistor Q⊥, wherein the N-type well functions both the NPN collector and the PNP base and thus may have a conflict. If the bias is great enough to force the PNP collector to generate current, the current flowing through the substrate resistor Rsub will further bias the base and emitter of the NPN bipolar transistor Q∥. Then, Q∥ will amplify more current to the N-type well resistor Rw and increase the bias of Q⊥. The repeated circulation generates a positive feedback, and the latch-up phenomenon will not stop unless the power source is removed.
The conventional approaches to avoid the latch-up phenomenon include: (1) increasing the distance between NMOS and PMOS, (2) increasing the dopant concentration of the base, (3) using an epitaxial layer in the substrate to increase the triggering bias voltage from the horizontal resistance, (4) shortening the distance between the contact of the source and the contact of the body (Butted Contact), (5) Trench Isolation, (6) using a guard ring to absorb the injected charges and prevent from the dual carrier operation, (7) using a SOI (Silicon On Insulation) technology, and (8) using a 3D stacked CMOS structure. The abovementioned approaches (1)-(6) can be interpreted as increasing Rw and Rsub in FIG. 1B to prolong or avoid the advanced triggering of Q⊥ and further inhibit the triggering of Q∥. Though approaches (1)-(6) can improve the latch-up problem, they cannot thoroughly exterminate the latch-up phenomenon, especially when high integration is required. Further, they all reduce the circuit density (integration) and decrease the switching speed of the circuit. In approach (7), MOS is completely constructed on the insulation layer, and the thyristor structure is almost vanished and hard to generate coupling current. Approach (7) can indeed prevent from the latch-up phenomenon. However, PMOS and NMOS are arranged on a plane side-by-side, and the integration is thus hard to increase. In approach (8), a MOS is formed over another MOS, and an oxide layer interposes therebetween. Although approach (8) can successfully overcome the latch-up phenomenon, it still has to overcome the problems of aligning masks and forming silicon semiconductor crystals on an oxide layer in the fabrication of 3D CMOS.
In using the low power consumption CMOS, the increased integration results in a high element density and delays the switching speed, which is another problem needing attention in addition to the latch-up problem.
SUMMARY OF THE INVENTION
The primary objective of the present invention is to solve the latch-up problem of the conventional CMOS and increase the integration of CMOS. The present invention improves the conventional PMOS into a coaxial PMOS (CPMOS for short), improves the conventional NMOS into a coaxial NMOS (CNMOS for short), and then joins the CPMOS and the CNMOS top-to-top to form a full-symmetric coaxial complementary metal-oxide-semiconductor field-effect transistor, whereby the latch-up problem is completely solved, the integration is promoted, and the response speed are increased. The full-symmetric coaxial complementary metal-oxide-semiconductor field-effect transistor of the present invention is abbreviated into CCMOSFET or CCMOS. In CCMOS of the present invention, two axial conductors of the CPMOS and the CNMOS are vertically cascaded, and the gates thereof are used jointly. In CCMOS of the present invention, each of the CPMOS and the CNMOS is coaxially symmetric by itself, and the elements of the CPMOS and the CNMOS are fully complementarily symmetric to each other. Similarly to the conventional 3D stacked CMOS structure, the vertically-stacked complementary CCMOSFET structure of the present invention is completely exempted from the latch-up problem and has a higher integration and a higher response speed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a top view schematically showing a conventional CMOS inverter;
FIG. 1B is a sectional view of the CMOS inverter shown in FIG. 1A ;
FIG. 2A is a sectional view schematically showing the latch-up state of a conventional CMOS inverter;
FIG. 2B is a diagram of an equivalent circuit of the conventional CMOS inverter shown in FIG. 2A ;
FIG. 3A is a perspective sectional view schematically showing a coaxial P-channel MOSFET according to the present invention;
FIG. 3B is a perspective sectional view schematically showing a coaxial N-channel MOSFET according to the present invention;
FIG. 4A is a top view schematically showing that current flows from a source to a drain in a conventional MOSFET;
FIG. 4B is a diagram schematically showing that current converges to an axial conductor according to the present invention;
FIG. 4C is a diagram schematically showing that current diverges uniformly from an axial conductor according to the present invention;
FIG. 5 is a perspective sectional view schematically showing a coaxial complementary MOSFET (CCMOSFET) according to the present invention;
FIG. 6 is a sectional view schematically showing a full complementarily-symmetric CCMOSFET according to the present invention; and
FIG. 7 is a diagram schematically showing a CCMOSFET inverter according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Refer to FIG. 3A , wherein an enhancement mode coaxial P-channel MOSFET is formed on an N-type substrate 301 or an N-type well is used to exemplify the present invention. The coaxial transistor structure comprises an annular P-type doped semiconductor drain area 302 , an annular P-type doped semiconductor source area 303 , an annular channel area 304 formed on the same substrate or well and arranged between the annular semiconductor drain area 302 and the annular semiconductor source area 303 , an annular polysilicon or conductor gate 306 arranged over the annular channel area 304 and insulated by an oxide layer 305 , a body 307 connected to the source and using the substrate or well as the reference potential, an external coaxial annular power supply conductor layer 308 connected to the body 307 and the annular source, and an inner axial conductor 309 connected to the semiconductor drain area where carriers concentrate. In the coaxial P-channel MOSFET, the annular elements and electrodes are fabricated into a coaxial structure. The annular gate 306 controls the direction of current. Refer to FIG. 4B . Different from the current flowing from the source to the drain in the conventional MOSFET shown in FIG. 4A , the current flows inward radially and uniformly from the external annular conductor layer 308 to the inner axial conductor 309 in the coaxial P-channel MOSFET of the present invention. Similarly to the conventional PMOS wherein the I/O direction may be varied, whether the current flows outward from the center or inward to the center is dependent on whether the source is arranged inside or outside. The Inventor had filed a Taiwan patent No. 095146963 “The Coaxial Light-Guide System Consisting Of Coaxial Light-Guide Fiber Basing Its Refractive Index Profiles On Radii And With Its Coaxial Both Semiconductor Light Sources And Semiconductor Detectors”. Based on the principle of a coaxial semiconductor structure disclosed in the abovementioned patent, the present invention modifies the conventional PMOS into a coaxial CPMOS. The axially symmetric structure provides a uniform built-in electric field, which drives the drift current to radially and equidistantly fast flow, whereby the influence of the diffusion current is avoided, and the response speed is increased, and the noise is reduced. Under the electric field generated by two coaxial electrodes, the electrons or holes move along the shortest path, i.e. moves along the direction of the greatest radial electric field. Thus, the carriers can rapidly converge or diverge to form the greatest current.
Refer to FIG. 3B , wherein an enhancement mode coaxial N-channel MOSFET is formed on a P-type substrate 311 or a P-type well is used to exemplify the present invention. The coaxial transistor structure comprises an annular N-type doped semiconductor drain area 312 , an annular N-type doped semiconductor source area 313 , an annular channel area 314 formed on the same substrate or well and arranged between the annular semiconductor drain area 312 and the annular semiconductor source area 313 , an annular polysilicon or conductor gate 316 arranged over the annular channel area 314 and insulated by an oxide layer 315 , a body 317 connected to the source and using the substrate or well as the reference potential, an external coaxial annular power supply conductor layer 318 connected to the body 317 and the annular source, and an inner axial conductor 319 connected to the semiconductor drain area where carriers concentrate. In the coaxial N-channel MOSFET, the annular elements and electrodes are fabricated into a coaxial structure. The annular gate 316 controls the direction of current. Refer to FIG. 4C . Different from the current flowing from the source to the drain in the conventional MOSFET shown in FIG. 4A , the current flows outward radially and uniformly from the inner axial conductor 319 to the external annular conductor layer 318 in the coaxial N-channel MOSFET of the present invention. Similarly to the conventional NMOS wherein the I/O direction may be varied, whether the current flows outward from the center or inward to the center is dependent on whether the source is arranged inside or outside. The Inventor had filed a Taiwan patent No. 095146963 “The Coaxial Light-Guide System Consisting Of Coaxial Light-Guide Fiber Basing Its Refractive Index Profiles On Radii And With Its Coaxial Both Semiconductor Light Sources And Semiconductor Detectors”. Based on the principle of a coaxial semiconductor structure disclosed in the abovementioned patent, the present invention modifies the conventional NMOS into a coaxial CNMOS. The axially symmetric structure provides a uniform built-in electric field, which drives the drift current to radially and equidistantly fast flow, whereby the influence of the diffusion current is avoided, and the response speed is increased, and the noise is reduced. Under the electric field generated by the two coaxial electrodes, the electrons or holes move along the shortest path, i.e. moves along the direction of the greatest radial electric field. Thus, the carriers can rapidly converge or diverge to form the greatest current.
Refer to FIG. 5 , wherein the CPMOS shown in FIG. 3A is flipped over to join with the CNMOS shown in FIG. 3B to form a full-symmetric coaxial CMOS (CCMOS). The axial conductor 309 and the axial conductor 319 are vertically connected to form an upper output terminal 501 and a lower output terminal 502 . The gates thereof jointly form an input voltage control terminal 503 , wherein 504 is a high voltage level VDD, and 505 is a low voltage level Vss. Refer to FIG. 6 . In the CCMOS of the present invention, the two axial conductors are vertically cascaded, and the gates are used jointly. Each of the upper and lower semiconductor devices is coaxially symmetric by itself; the upper and lower semiconductor devices are completely complementarily symmetric to each other. The elements of the PNP transistor of the upper CPMOS are completely separated from the elements of the NPN transistor of the lower CNMOS; therefore, the latch-up problem is thoroughly solved. Different from the conventional CMOS structure wherein elements are arranged side-by-side, the CCMOS of the present invention has a vertically-stacked structure and thus has a higher integration. In the coaxial transistor structure of the present invention, the built-in electric field created by the PN junction is a uniform axially-symmetric electric field. The carriers flow equidistantly radially to converge inward or diverge outward, whereby a higher response speed is attained, and noise is reduced.
The present invention modifies the conventional PMOS into CPMOS, the conventional NMOS into CNMOS, and then joins the CPMOS and CNMOS top-to-top to form a full-symmetric CCMOS, whereby the latch-up problem is thoroughly solved, and whereby the integration and response speed are increased. The coaxialized MOSFET also realizes the function of a transistor—“varying resistor”, “adjustable resistor” “maximizes the built-in resistor to turn off current or minimizes the built-in resistor to conduct current”. The present invention is a perfect presentation of microelectronics, wherein the radial current converges or diverges equidistantly so smooth to save energy and so fitness for the nature just like blossom up and blossom down.
Below, an embodiment is used to further demonstrate the present invention.
Refer to FIG. 7 for an inverter formed of CCMOSFET. The inverter is realized via top-to-top joining the CPMOS shown in FIG. 3A and the CNMOS shown in FIG. 3B . The axial conductor 309 and the axial conductor 319 are vertically connected to form an upper output terminal 701 and a lower output terminal 702 . The gates thereof jointly form an input voltage control terminal 703 . In each CCMOSFET, the two axial conductors 309 and 319 are vertically cascaded, and the gates are used jointly. Each of the upper and lower semiconductor devices is coaxially symmetric by itself; the upper and lower semiconductor devices are completely complementarily symmetric to each other. The inverters are separated by separating layers 706 . When a low voltage level is input to the input voltage control terminal 703 , the low voltage level of the common gate causes the P-channel of CPMOS thereabove to conduct current. The positive-hole carrier source of the source 704 supplies electricity at a high voltage VDD, and the holes radially converge to the cascaded axial conductors; then the upper output terminal 701 and lower output terminal 702 output a high voltage level. In other words, the original low voltage level is pulled up to be a high voltage level. When a high voltage level is input to the input voltage control terminal 703 , the high voltage level of the common gate causes the N-channel of CNMOS therebelow to conduct current. The electron carrier source of the source 705 supplies electricity at a negative voltage Vss, and the electrons radially converge to the cascaded axial conductors; then the upper output terminal 701 and the lower output terminal 702 output a low voltage level. In other words, the original high voltage level is pulled down to be a low voltage level. If the low voltage level Vss is grounded, Vss is regarded as the ground voltage. If the input voltages are dual-state logic signals, the ground voltage is a negative voltage level. Thus is realized the function of an inverter. The coaxialized and vertically-stacked structure can promote the integration of the integrated circuit. Further, the coaxial transistor has a uniform electric field to drive current to fast converge or diverge by nature, whereby the power consumption is saved.
The figures and the elements denoted by numerals used in the abovementioned embodiments are only to schematically exemplify the present invention but not to cover all the characteristics of the present invention. Further, the elements in the figures are based on the spirit of the present invention but not drawn according to the physical proportion and number thereof. Therefore, the scope of the present invention is not limited by the figures.
The CMOSFET, CCMOSFET and the CCMOSFET inverter described above are only the embodiments to exemplify the present invention but not to limit the scope of the present invention. Therefore, any equivalent embodiment or application according to the spirit of the present invention is to be also included within the scope of the present invention.
The CMOSFET and the CCMOSFET inverter of the present invention not only have a high integration and a high response speed but also are thoroughly exempted from the latch-up problem. The present invention applies to various digital logic ICs and various high-speed mass memories, such as coaxial SRAM, coaxial DRAM, and coaxial ROM, or even coaxial DHBT (Double Heterojunction Bipolar Transistor). The coaxial transistor of the present invention can be fabricated with a lower cost and operates more power-efficiently.
The abovementioned coaxial transistor devices of the present invention can be singly used to control the conduction state, multi-used or jointly stacked and applied to various logic circuits, wherefore the present invention will contribute much to the electronic industry.
The present invention has been fully disclosed above, which is sufficient to enable the persons skilled in the art to understand, make, and use the present invention. However, it is not intended to limit the scope of the present invention. Any equivalent modification or variation is to be also included within the scope of the present invention, which is based on the claims stated below. | The present invention discloses a coaxial transistor formed on a substrate, particularly a coaxial metal-oxide-semiconductor field-effect transistor (CMOSFET). The chips or substrates of the CMOSFETs can be stacked up and connected via through-holes to form a coaxial complementary metal-oxide-semiconductor field-effect transistor (CCMOSFET), which is both full-symmetric and full-complementarily, has a higher integration and is free of the latch-up problem. | 7 |
FIELD OF THE INVENTION
[0001] This invention relates to automatic pool cleaners (APCs) configured to move autonomously within liquid-containing bodies such as swimming pools and spas and more particularly, although not necessarily exclusively, to components of APCs that frictionally contact surfaces of the pools and spas.
BACKGROUND OF THE INVENTION
[0002] Commonly-owned U.S. Patent Application Publication No. 2011/0314617 of van der Meijden, et al., discloses various components of APCs. Among components illustrated in the van der Meijden application are devices referenced as “scrubbers.” As detailed in the van der Meijden application, an exemplary scrubber may include blades, a shaft, and optionally a gear.
In use, [the] scrubber desirably rotates about [the] shaft so as to move water . . . toward [an] inlet of [a] body of [an] automatic pool cleaner. Such rotation may be caused by interaction of [the] gear with a corresponding gear or other device typically located within [the] body.
See van der Meijden, pp. 1-2, ¶0026 (numerals omitted). The rotation and evacuation of water entering the inlet additionally produces “down force” tending to enhance traction of the APC as it moves along a surface within a pool.
[0004] Also described in the van der Meijden application as another optional part of a scrubber is a “wear surface.” If present, the wear surface may be located centrally among the blades of the scrubber and coaxial with the shaft. At least at times in use, the wear surface may contact a surface to be cleaned. See id., p. 2, ¶0028.
[0005] Even though the van der Meijden application contemplates frictional contact between the wear surface and surfaces of a pool or spa, additional scrubbing action may be desirable—at least at times—for cleaning purposes. Including brushes spaced from (i.e. not coaxial with) the shaft of a scrubber also may be advantageous, as may be utilizing bristles which contact a surface as the scrubber rotates about the shaft. Removably attaching the brushes to a scrubber further may be beneficial, as in such cases the brushes may be removed from the scrubber when not needed.
SUMMARY OF THE INVENTION
[0006] The present invention provides these types of brushes useful especially (although not necessarily exclusively) with the scrubbers and APCs of the types identified in the van der Meij den application. Brushes of the invention may clip to a hub of a scrubber so as to attach to, and detach from, the scrubber easily. The brushes also preferably flex when a scrubber rotates.
[0007] At least some versions of the brushes may include fingers having bristles protruding outward on either or both of opposed sides of the fingers. Prior to rotation of the scrubbers, the fingers nominally are generally perpendicular to the surface on which the associated APC rests. As scrubbers rotate, however, the fingers flex (e.g. lay over) and become more parallel to the surface. Flexing of the fingers in this manner in turn causes bristles on one side of fingers to become more perpendicular to the surface, thus readily frictionally contacting it.
[0008] Because in use scrubbers of the present invention rotate about an axis generally perpendicular to the pool surface, their brush speeds relative to the surface are faster than those of passive devices (which typically are dragged along the surface) or rollers (which typically rotate about an axis parallel to the surface and in the same direction as the wheels of the cleaner). Such rotation also requires less surface-area contact between the brushes and pool surface to scrub an equivalent width of pool surface than would a roller, whose length must span that entire width. This decreased surface-area contact of the brushes produces less resistance on the drive system of the APC than would rollers, potentially enhancing the longevity and robustness of the drive system.
[0009] Brushes may be attached as desired to a scrubber. Presently preferred is that at least two brushes be used with a scrubber and positioned symmetrically about the shaft. Fewer or more than two brushes may be used in connection with any particular scrubber, however, and conceivably more than one brush may be attached in a particular location.
[0010] It thus is an optional, non-exclusive object of the present invention to provide components for APCs.
[0011] It also is an optional, non-exclusive object of the present invention to provide improvements to scrubbers of the type identified in the van der Meij den application.
[0012] It is another optional, non-exclusive object of the present invention to provide brushes configured to contact to-be-cleaned surfaces.
[0013] It is an additional optional, non-exclusive object of the present invention to provide brushes that may clip, or otherwise attach, to scrubbers so as to rotate as the blades rotate.
[0014] It is, moreover, an optional, non-exclusive object of the present invention to provide brushes that include flexible fingers with bristles protruding therefrom.
[0015] It is a further optional, non-exclusive object of the present invention to provide brushes whose fingers flex as their associated blades rotate, thus causing contact between their bristles and a to-be-cleaned surface of a pool or spa.
[0016] It is yet another optional, non-exclusive object of the present invention to provide brushes which rotate about an axis perpendicular to the to-be-cleaned surface so as to produce faster speeds and less load on drive systems than do certain passive devices and rollers.
[0017] Other objects, features, and advantages of the present invention will be apparent to those skilled in relevant fields with reference to the remaining text and the drawings of this application.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1A is an elevational view of an exemplary scrubber similar to that of those of the van der Meijden application.
[0019] FIG. 1B is a perspective view of the scrubber of FIG. 1A .
[0020] FIGS. 2A-C are various views of an exemplary brush configured to attach to the scrubber of FIG. 1A .
[0021] FIG. 3 is an elevational view of the scrubber of FIG. 1A to which two brushes of FIGS. 2A-C have been attached.
[0022] FIG. 4 is a perspective view of the scrubber of FIG. 1A to which one brush of FIGS. 2A-C has been attached for purposes of showing its flexibility.
[0023] FIG. 5 is a perspective view of an APC including two scrubbers, to each of which brushes have been attached in a manner similar to FIG. 3 .
DETAILED DESCRIPTION
[0024] Depicted in FIGS. 1A-B is exemplary scrubber 10 . Scrubber 10 , which is generally similar to scrubbers of the van der Meij den application, may include blades 14 and shaft 18 . Also illustrated in FIGS. 1A-B is hub 20 interconnecting blades 14 and shaft 18 . In use, scrubber 10 desirably rotates about shaft 18 so as to move water toward an inlet 21 of a cleaner such as APC 22 (see FIG. 5 ). When the APC 22 is upright on a bottom surface of a pool, shaft 18 will be generally perpendicular to the plane of the bottom surface and thus scrubber 10 will rotate about an axis perpendicular (or generally so) to the bottom surface.
[0025] Consistent with the discussion in the van der Meijden application, blades 14 preferably are “semi-rigid” in nature, meaning that they have sufficient flexibility to accommodate passage into inlet 21 of APC 22 , without blockage, of at least some larger types of debris often found in outdoor swimming pools. The term “semi-rigid” also means that blades 14 nevertheless have sufficient rigidity to move volumes of water toward the inlet 21 of the cleaner as they rotate about shaft 18 . A presently-preferred material from which blades 14 is made remains molded thermoplastic polyurethane, although other materials may be used instead.
[0026] Scrubber 10 advantageously may include six blades 14 extending radially from shaft 18 . Fewer or greater numbers of blades 14 may be employed as appropriate, however. As illustrated in FIG. 5 , two scrubbers 10 preferably are employed as part of APC 22 , with each scrubber 10 being positioned at least partly to a side of inlet 21 of the APC 22 . Again, though, fewer or greater numbers of scrubbers 10 may be utilized, and each or any scrubber 10 may be positioned in any suitable location.
[0027] As shown in FIG. 1A , many of the six blades 14 are circumferentially spaced approximately forty-five degrees, rather than approximately sixty degrees, from adjacent blades 14 . This is because attachment assemblies 26 of hub 20 have, in effect, replaced the seventh and eighth blades. The two attachment assemblies 26 are at least partially visible in FIG. 1A spaced circumferentially about shaft 18 by approximately one hundred eighty degrees. Symmetrical positioning of attachment assemblies 26 about shaft 18 presently is preferred, although situations may arise in which an odd number of assemblies 26 , or asymmetrical positioning of an even number of assemblies 26 , is desired.
[0028] The exemplary attachment assembly 26 of FIG. 1A may comprise at least one recess 30 A. In the version of scrubber 10 depicted in FIG. 1A , recess 30 A is formed by a pair of spaced walls 34 A-B connected to hub 20 . A second recess 30 B, formed by a pair of spaced walls 38 A-B connected to hub 20 , also appears in FIG. 1A .
[0029] Shown especially in FIGS. 2A-C is exemplary brush 42 . Included as part of brush 42 is member 46 , which is sized and shaped to be frictionally fitted into recesses 30 A and 30 B. Concurrently, clips 50 of brush 42 frictionally slide along walls 34 A-B and 38 A-B. Manipulating brush 42 in this manner connects the brush 42 to scrubber 10 for use—as shown in FIGS. 3-5 . Because brush 42 is likely to wear through use, it preferably may be detached from scrubber 42 (as through manual force, for example) for replacement.
[0030] Also included as parts of brush 42 are brush body 54 , fingers 58 , and bristles 62 . Fingers 58 depend from body 54 , with each finger 58 comprising opposed major sides 66 A-B. Bristles 52 protrude outward from these major sides 66 A-B. Although FIGS. 2A-5 illustrate three fingers 58 depending from each body 54 , more or fewer fingers 58 may be present instead if appropriate or desired.
[0031] Fingers 58 beneficially are flexible. Accordingly, as shown in FIG. 4 , fingers 58 may flex as blades 14 rotate about shaft 18 . Whereas major sides 66 A-B are nominally vertical when APC is upright (e.g. FIG. 5 ) and blades 14 are not rotating, flexing of fingers 58 causes major sides 66 A-B to become more closely parallel to the surface to be cleaned. Consequently, because bristles 52 protrude outward from major sides 66 A-B, these bristles 52 become more closely perpendicular to the to-be-cleaned surface as the fingers 58 flex. Bristles 52 thus in use may contact the to-be-cleaned surface so as to “scrub” the surface and suspend bottom-dwelling debris into the water of the pool for evacuation into inlet 21 of APC 22 . Consistent with other suction-type APCs, APC 22 also may include body 70 through which the evacuated water may flow to outlet 74 and then into a hose, all under influence of a pump.
[0032] Moreover, because scrubber 10 rotates about an axis perpendicular to the to-be-cleaned surface, the speed of movement of brushes 42 (and hence of bristles 52 ) relative to the surface may be faster than that of passive devices which merely are dragged along the surface. This relative speed of movement likewise may be faster than that of rollers, which typically rotate about axes parallel to the surface and in the same direction as the wheels or tracks of an associated cleaner. Rotation of scrubber 10 about the perpendicular axis also requires approximately fifty percent less surface-area contact between brushes 42 and the pool surface to scrub an equivalent width of pool surface than would a roller, whose length must span that entire width. This decreased surface-area contact of brushes 42 produces less resistance on the drive system of APC 22 than would rollers, potentially enhancing the longevity and robustness of the drive system.
[0033] If scrubber 10 is configured to rotate only in one direction, bristles 52 need necessarily be present only on whichever of major sides 66 A or 66 B is the “leading” side for purpose of the rotation (as the other, “trailing” major side will flex away from the to-be-cleaned surface). It nevertheless may be advantageous to include bristles 52 on the trailing major side 66 B or 66 A of brush 42 so that, when bristles 52 on the leading side wear, brush 42 may be switched to a circumferentially opposite location on scrubber 10 so that the previously-trailing side becomes the leading side and presents unworn bristles 52 to the to-be-cleaned surface. This switch effectively can double the useful life of a brush 42 . (And of course, if scrubber 10 ever is configured to rotate both clockwise and counterclockwise, including bristles 52 on both major sides 66 A-B may be valuable.)
[0034] The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of the present invention. Modifications and adaptations to these embodiments will be apparent to those skilled in the art and may be made without departing from the scope or spirit of the invention. Also, although “pool” and “spa” are sometimes used separately, any reference to “pool” herein may include a spa, hot tub, or other vessel in which water is placed for swimming, bathing, therapy, or recreation. Finally, incorporated herein in their entirety by this reference are the contents of the van der Meij den application. | Components of automatic pool cleaners (APCs) are detailed. The components may include brushes configured to attach to blades of scrubbers of the APCs. The flexible brushes may rotate as their associated blades rotate and have fingers which flex so as to adduce contact between a to-be-cleaned pool or spa surface and bristles protruding outward from sides of the fingers. | 4 |
FIELD OF THE INVENTION
The invention relates to production of aliphatic ω-cyanocarboxamides from α,ω-dinitriles using a Pseudomonas putida-derived biocatalyst.
DESCRIPTION OF RELATED ART
The hydrolysis of nitriles has long been useful for the production of various amide intermediates in processes for making polymers such as nylon and polyacrylamide. Processes involving enzymatic conversion of nitrile substrates are sometimes favored over chemical synthesis for their production of fewer harmful reaction by-products and for greater reaction specificity.
The occurrence of nitrile hydrolyzing enzymes has been widely described. Within this family of enzymes, two broad classes are generally recognized. The first includes the nitrile hydratases which catalyze the addition of one molecule of water to the nitrile, resulting in the formation of the corresponding amide:
Reaction 1
R--CN+H.sub.2 O>>>>>RCONH.sub.2
The second group includes the nitrilases which catalyze the addition of two molecules of water to the nitrile resulting in the direct formation of the corresponding carboxylic acid plus ammonia, without the intermediate formation of the corresponding amide:
Reaction 2
R--CN+2H.sub.2 O>>>>>RCOOH+NH.sub.3.sup.+
In addition, all known organisms containing nitrile hydratases (Reaction 1) also contain an amidase enzyme, capable of catalyzing the addition of one molecule of water to the amide resulting in the formation of the corresponding carboxylic acid plus ammonia:
Reaction 3
RCONH.sub.2 +H.sub.2 O>>>>>RCOOH+NH.sub.3
For the purposes of industrial processes, the presence of this amidase activity in biocatalysts capable of carrying out Reaction 1, may or may not be desirable.
A wide variety of bacterial genera are known to possess nitrile hydratase and amidase activities including Rhodococcus, Pseudomonas, Alcaligenes, Arthrobacter, Bacillus, Bacteridium, Brevibacterium, Corynebacterium, and Micrococcus. Wild type microorganisms known to possess nitrile hydratase activity have been used to convert nitriles to amides and carboxylic acids. The enzymatic hydrolysis of aliphatic nitriles by methods employing bacterial strains of the above mentioned genera is well known. For example, U.S. Pat. Nos. 5,179,014, 5,200,331, and 5,334,519 teach processes for enzymatic hydration of aliphatic or aromatic nitriles having 2 to 8 carbon atoms to the corresponding amide using strains of Rhodococcus. Similarly, U.S. Pat. No. 4,637,982 of Yamada et al. which issued Jan. 20, 1987, teaches a process for enzymatic hydration of aliphatic nitriles having 2 to 4 carbons using a strain of Pseudomonas. U.S. Pat. No. 4,366,250 teaches the use of Bacillus, Bacteridium, Micrococcus and Brevibacterium in a method for the preparation of L-amino acids from the corresponding racemic amino nitriles. Finally, in WO 92/05275 the Applicants teach a biologically-catalyzed method for converting a racemic alkyl nitrile to the corresponding R- or S-alkanoic acid through an intermediate amide using members of the bacterial genera Pseudomonas spp. (e.g., putida, aureofaciens, Moraxella spp.) and Serratia (e.g., Serratia liquefaciens).
In addition to the use of wild type organisms, recombinant organisms containing heterologous genes for the expression of nitrile hydratase are also known for the conversion of nitriles. For example, Cerebelaud et al. (WO 95/04828) teach the expression in E. coli of nitrile hydratase genes isolated from C. testosteroni. The transformed hosts effectively convert nitriles to amides where the nitrile substrate contains one nitrile and one carboxylate group. Similarly, Beppu et al. (EP 5024576) disclose plasmids carrying both nitrile hydratase and amidase genes from Rhodococcus capable of transforming E. coli where the transformed host is then able to use isobutyronitrile and isobutyramide as enzymatic substrates.
Heterobifuntional compounds are useful as polymer intermediates as well as intermediates in high value agricultural or pharmaceutical products. From aliphatic, α,ω-dinitriles, it is sometimes desirable to produce such heterobifunctional compounds by hydrolyzing a single functional group without further modification, for example,
Reaction 4
CN--X--CN>>>>>>>>CN--X--CONH.sub.2
where X is a C 1 -C 8 or an allicyclic or aromatic six carbon ring. Such "regioselectivity" is often beyond the capability of chemical catalysts. However, biocatalysts are often capable of recognizing subtle structural differences which may allow useful regioselective biocatalysts to be developed. In the case described, such a process requires a biocatalyst with both a nitrile hydratase of proper selectivity and the absence of amidase activity that could result in further hydrolysis of the amide. In the field of nitrile biocatalysts, few such regioselective biocatalysts resulting in ω-cyanocarboxamide compounds have been described. For example, European Patent Application 178 106, published Apr. 16, 1986, discloses selective transformation of one of the cyano groups of a dinitrile to the corresponding carboxylic acid, amide, ester or thioester using a mononitrilase derived from Bacillus, Bacteridium, Micrococcus or Brevibacterium. JP 02154692 describes the conversion of some aliphatic dinitriles (<C 8 ) to the corresponding ω-cyanocarboxamide derivatives using Acinetobacter strain (FERM P-10432). U.S. Pat. No. 4,629,700 describes conversion of aromatic dinitriles to the corresponding mono or diamides using Rhodococcus strains. The use of biocatalysts from the Pseudomonas genus for the regioselective conversions of dinitriles to aliphatic omega-cyanocarboxamides has not been anticipated in the art. The only previous report of dinitrile conversion by a Pseudomonas strain comments that only minor amounts of the heterobifunctional compounds cyanobutyric acid and cyanobutyramide were detected, while glutaric acid was the major product detected following glutaronitrile (a C 4 dintrile) hydrolysis by Pseudomonas sp. K9 (Yamada et al., J. Ferment. Technol. 58(6):495-500, 1980). High levels of amidase activity caused rapid diacid formation, making the strain useless as a biocatalyst for ω-cyanocarboxamide production.
Pseudomonas strains often show growth rates faster than other microbes known in the art as biocatalysts useful in producing ω-cyanocarboxamides. Rapid growth makes biocatalyst production more efficient. Therefore, the ability to produce Pseudomonas-derived biocatalysts leads to a more efficient overall process for ω-cyanocarboxamide production.
SUMMARY OF THE INVENTION
The invention relates to a method to produce aliphatic ω-cyanocarboxamides of Formula I
NC--CH(R.sub.1)(CH).sub.n CH(R.sub.2) C(O)NH.sub.2
where
n=1-8 and R 1 or R 2 are either H or CH 3 , from aliphatic α,ω-dinitriles of Formula II
NC--CH(R.sub.1)(CH).sub.n CH(R.sub.2)CN
where
n=1-8 and R 1 or R 2 are either H or CH 3 , using biocatalysts having regioselective nitrile hydratase activity derived from Pseudomonas putida and recovering the aliphatic ω-cyanocarboxamides from the medium.
In one embodiment, biocatalysts derived from Pseudomonas putida are capable of producing ω-cyanocarboxamide products from dinitriles without significant by-product production, increasing the yield of ω-cyanocarboxamides relative to that obtained when using non-regioselective biocatalysts.
In a specific embodiment, 5-cyanopentanamide is produced from adiponitrile with a product:byproduct ratio (5-cyanovaleramide:adipamide) of ≧30:1 at various temperatures and starting concentrations of adiponitile, using regioselective biocatalysts derived from P. putida 3L-G-1-5-1a-1 (ATCC 55736).
In another specific embodiment, 4-cyannopentanamide and 4-cyano-2-methylbutyramide are produced from 2-methylglutaronitrile with a product:byproduct ratio (4-methyl-4-cyanobutyramide and 2-methyl-4-cyanobutyramide:2-methylglutaramide) of ≧15:1 at various temperatures and starting concentrations using biocatalysts derived from P. putida 3L-G-1-5-1a-1 (ATCC 55736).
In a third specific embodiment, 5-cyanopentanamide is produced from adiponitrile with a product:byproduct ratio of ≧100:1 at 30° C. and various starting concentrations of adiponitile using biocatalysts derived from P. putida 20-5-SBN-1b (ATCC 55735).
BRIEF DESCRIPTION OF THE BIOLOGICAL DEPOSITS
Applicants have made the following biological deposits under the terms of the Budapest Treaty:
______________________________________ International Depository Date ofDepositor Strain Designation Accession No. Deposit______________________________________Pseudomonas putida 3L-G-1-5-1a-1 ATCC 55736 26 January 1996Pseudomonas putida 20-5-SBN-1b ATCC 55735 26 January 1996______________________________________
As used herein, "ATCC" refers to the American Type Culture Collection international depository located at 12301 Parklawn Drive, Rockville, Md. 20852, U.S.A. The "ATCC No." is the accession number to cultures on deposit with the ATCC.
DETAILED DESCRIPTION OF THE INVENTION
The present invention recites a process for the production of aliphatic ω-cyanocarboxamides from α,ω-dinitriles utilizing biocatalysts derived from Pseduomonas putida having regioselective nitrile hydratase activity. The products of the present invention are useful primarily as precursors for polymers, solvents, and chemicals of high value in the agricultural and pharmaceutical industries.
The following definitions will be used for interpretation of the claims and specification.
The term "product:byproduct ratio" refers to the weight or molar ratio of desirable reaction product(s) to undesirable reaction product(s).
The term "nitrile hydratase", abbreviated "NHase", will refer to an enzyme capable of catalyzing the following reaction: R--CN+H 2 O>>>>>RCONH 2 .
The terms "omega-cyanocarboxamide" or "ω-cyanocarboxamide" will refer to a chemical compound of the formula NC--R--C(O)NH 2 .
Abbreviations of substrate or product names are as follows:
4-CMBAM 4-cyano-2-methylbutyramide
4-CPAM 4-cyanopentanamide
2-MGN 2-methylglutaronile
2-MGAM 2-methylglutaramide
ADN adiponitrile
The term "biocatalyst" refers to any substance, organic matter, compound or mixtures of compounds, derived from a biological source, which is capable of catalyzing a specific desired chemical reaction. Biocatalysts may be purified enzymes, partially purified enzymes, crude cell lysates or whole cells. Biocatalysts that include whole cells will be referred to as: "whole cell biocatalysts" or "whole cell catalysts". Whole cell catalysts may be either living or dead cells and may be utilized either in free suspension or immobilized on a suitable support. Immobilized catalysts of this sort will be referred to as "immobilized whole cell catalysts". Biocatalysts of particular significance within the context of the present invention are derived from Pseudomonas putida and will be referred to as "Pseudomonas putida-derived biocatalysts". The term "derived" is used to indicate the source of the biocatalyst regardless of the particular form used (i.e., whole cells, organic material, crude cell lysates, or purified or partially purified enzymes, either in free suspension or immobilized).
As used herein, "NRRL" refers to the Northern Regional Research Laboratory, Agricultural Research Service Culture Collection international depository located at 11815 N. University Street, Peoria, Ill. 61604, U.S.A. The "NRRL No." is the accession number to cultures on deposit at the NRRL.
As used herein, "FERM" refers to The Fermentation Research Institute, now known as The National Institute of Bioscience and Human Technology (NIBHT), Agency of Industrial Science and Technology, Ministry of International Trade and Industry, 1-3, higashi 1-chome, Tsukuka-shi, Ibaraki-ken 305, Japan. The "FERM No." is the accession number to cultures on deposit with the FERM.
Biocatalysts useful in the described process are very selective for the hydrolysis of α,ω-dinitriles to the corresponding ω-cyanocarboxamides. Biocatalysts yielding a ω-cyanocarboxamides:by-product ratio of >5:1 may be useful in such a process with preferred biocatalysts showing a ratio of >20: 1. The nitrile hydratase activity of P. putida 3L-G-1-5-1a-1 (ATCC 55736) cells is very selective for the hydrolysis of α,ω-dinitriles to the corresponding ω-cyanocarboxamides. This catalyst hydrolyzes adiponitrile to 5-cyanopentanamide in high yield, with adipamide being the only by-product produced in the reaction. The ratio of 5-cyanopentanamide to adipamide observed over the course of the adiponitile hydrolysis reaction is typically 50:1 (molar ratio), with a selectivity to 5-cyanopentanamide of ca. 98% at 100% conversion of adiponitrile. The whole cells can be used as catalyst in a reaction mixture without any pretreatment or they can be immobilized in a polymer matrix (e.g., alginate beads or polyacrylamide gel (PAG) particles) or on an insoluble solid support (e.g., controlled-pore glass) to facilitate recovery and reuse of the catalyst. Methods for the immobilization of cells in a polymer matrix or on an insoluble solid support have been widely reported and are well-known to those skilled in the art (Chibata et al., (1986), Methods of Cell Immobilization, Ch. 18 in Manual of Industrial Microbiology, A. L. Demain & N. A. Solomon(ed.), ASM, Washington, DC). The nitrile hydratase enzyme separated from the whole cells can also be used directly as catalyst, or the enzyme can be immobilized in a polymer matrix or on an insoluble support. These methods have also been widely reported and are well-known to those skilled in the art (Bernath et al., (1986), Methods of Enzyme Immobilization, Ch. 19 in Manual of Industrial Microbiology, A. L. Demain & N. A. Solomon(ed.), ASM, Washington, DC).
When the nitrile hydratase activity of P. putida 3L-G-1-5-1a-1 (ATCC 55736) cells is used to hydrolyze the unsymmetrically-substituted 2-methylglutaronitrile (2-MGN), the corresponding ω-cyanocarboxamides 4-cyano-2-methylbutyramide (4-CMBAM) and 4-cyanopentanamide (4-CPAM) are produced with high selectivity, with 2-methylglutaramide (2-MGAM) being the only by-product produced in the reaction: ##STR1## The ratio of 4-CMBAM to 4-CPAM produced over the course of the hydrolysis reaction is ca. 2.4:1, and the selectivity to the ω-cyanocarboxamides is typically 95% at 100% conversion of 2-methylglutaronitrile, with an additional 5% selectivity to 2-methylglutaramide.
In the accompanying Examples, any reaction mixture containing amounts of dinitrile which exceed the solubility of the dinitrile under the described reaction conditions will be a two-phase reaction (aqueous phase and non-aqueous phase). Many dinitriles are only moderately water-soluble and solubility is affected by temperature and salt concentration of the aqueous phase. For example, adiponitrile has a solubility limit (25° C., 20 mM phosphate buffer, pH 7) of 0.597M and under the same conditions 2-methylglutaronitrile has a solubility limit of 0.52M. As a result, reaction mixtures may contain an aqueous and non-aqueous phase. Although the appearance of reaction mixture is altered, there is no affect on the selectivity of the α,ω-dinitrile conversion to ω-cyanocarboxamides. The nitrile dissolves into the aqueous phase as the reaction progresses and a single phase reaction is eventually obtained.
The desired aliphatic omega-cyanocarboxamide product is recovered using techniques common to the art. At the conclusion of the reaction, where the conversion of the dinitrile is typically >95%, the resulting aqueous mixture is centrifuged and the biocatalyst is recovered for reuse in a subsequent reaction. The resulting supernatant is filtered, and the volume of the supernatant may be concentrated by removal of water (for example, by rotary evaporation under reduced pressure). The ω-cyanocarboxamide product(s) is isolated from the supernatant (or concentrated supernatant) by extraction with a suitable organic solvent in which the product nitrile amide is preferentially soluble (e.g., ethyl acetate). The combined organic extracts are then combined, stirred with a suitable drying agent (e.g., magnesium sulfate), filtered, and the solvent removed (e.g., by rotary evaporation) to produce the desired product in high yield and in high purity (typically 98-99% pure). If desired, the product nitrile amide can be further purified by recrystallization or distillation. In the case of 5-cyanopentanamide, or the mixture of ω-cyanocarboxamides produced from the hydrolysis of 2-methylglutaronitrile, recrystallization from ethyl acetate or toluene results in ω-cyanocarboxamide purifies in excess of 99.5%.
EXAMPLES
Materials and Methods
Identification and Isolation of Biocatalysts
The microorganisms used in the present invention belong to the genus Pseudomonas. Representative Pseudomonas putida strains are listed above in the Brief Description of the Biological Deposits. In addition, the following Pseudomonas strains were found to produce the desired product: P. putida 5B-MGN-2p (NRRL-18668), P. putida 3L-H-2-6-1p, P. chlororaphis B23 (FERM-B 187), Pseudomonas sp. 3L-H-9-6-2p, and P. putida 2-H-9-5-1a.
With the exception of P. chlororaphis B23, all of the strains used by the Applicants were isolated from soil collected in Orange, Tex. Standard enrichment procedures were used with the following medium (PR Basal Medium, pH 7.2).
______________________________________PR Basal Medium g/L______________________________________KH.sub.2 PO.sub.4 8.85Sodium citrate 0.225MgSO.sub.4 7H.sub.2 O 0.5FeSO.sub.4 7H.sub.2 O 0.05FeCl.sub.2 4H.sub.2 O 0.0015CoCl.sub.2 6H.sub.2 O 0.0002MnCl.sub.2 4H.sub.2 O 0.0001ZnCl.sub.2 0.00007H.sub.3 BO.sub.3 0.000062NaMoO.sub.4 2H.sub.2 O 0.000036NiCl.sub.2 6H.sub.2 O 0.000024CuCl.sub.2 2H.sub.2 O 0.000017Biotin 0.00001Folic Acid 0.00005Pyridoxine.HCl 0.000025Riboflavine 0.000025Nicotinic Acid 0.000025Pantothenic Acid 0.00025Vitamin B12 0.000007p-Aminobenzoic Acid 0.00025______________________________________
The following modifications were made to the PR basal medium for the enrichments described above:
______________________________________Strain Enrichment Nitrile (25 mM) Other______________________________________3L-G-1-5-1a-1 2-methylglutaronitrile (2-MGN) pH 5.6(ATCC 55736) (Aldrich Chemical Co., Milwaukee, WI)5B-MGN-2p 2-methylglutaronitrile (2-MGN) pH 5.6(NRRL-18668)3L-H-2-6-1p acetonitrile (Aldrich Chemical Co., Milwaukee, WI)20-5-SBN-1b S-methylbutyronitrile(ATCC 55735) (Aldrich Chemical Co., Milwaukee, WI)3L-H-9-6-2p undecylcyanide pH 5.6 (Aldrich Chemical Co., Milwaukee, WI)2-H-9-5-1a undecylcyanide______________________________________
Strains were originally selected based on growth and ammonia production on the enrichment nitrile. Isolates were purified by repeated passing on Bacto Brain Heart Infusion Agar (Difco, Detroit, Mich.) followed by screening for ammonia production from the enrichment nitrile. Purified strains were identified by Acculab (Newark, Del., USA) based on their membrane fatty acid profiles by gas chromatography using Sherlock, v. 1.06, software and databases.
Microorganism Screening for Nitrile Hydrolysis Activity
For testing nitrile hydrolysis activity, PR basal medium with 10 g/L glucose was used to grow cell material. The medium was supplemented with 25 mM 2-methylglutaronitrile. A 10 mL inoculum of supplemented PR medium was inoculated with 0.1 mL of frozen stock culture. Following overnight growth at room temperature(22°-25° C.) on a shaker at 250 rpm, the 10 mL inoculum was added to 990 mL of fresh medium in a 2 L flask. The cells were grown overnight at room temperature with stirring at a rate high enough to cause bubble formation in the medium. Cells were harvested by centrifugation, washed once with 50 mM phosphate buffer (pH 7.2)/15% glycerol and the concentrated cell paste was immediately frozen on dry ice and stored at -65° C. Thawed cell pastes were used for testing nitrile hydrolysis activity. The microorganism should contain the desired regioselective nitrile hydrolyzing in the absence of significant interfering amidase activity. Mutation is a natural pheneomenon in microorganisms. Mutations favoring this desirable property might be found in the native strain, leading to enhanced regioselective NHase activity or to decreased non-regioselective Nhase activity or decreased amidase activity. Thus, even mutants of the native strain may be used to carry out the process of the instant invention. Finally, the regioselective NHase enzymes may also be produced in non-native microbial strains through techniques common to the art of genetic engineering (Sambrook et al. (1989), Molecular Cloning, 2rid Ed., V. 1, 2, & 3; Cold Spring Harbor Laboratory Press, USA) leading to the production of desirable biocatalysts.
Selection of Microbial Biocatalysts
To produce biocatalyst for process demonstration (as for Examples 2, 3, 4, 5, 6, 7 and 8), a vial containing 10 mL of PR medium with 1% glucose, 0.001% yeast extract and 10 mM butyronitrile was inoculated with 0.1 mL of frozen stock culture. Following overnight growth at 30° C. with shaking at 250 rpm, the growing cell suspension was transferred to 1 L of the same medium in a 2 L flask and growth continued at 30° C. with shaking. The 1 L growing cell suspension was then added to 9 L of the same medium in a 10 L fermentation vessel where growth continued overnight. Nominal conditions in the fermenter were: ≧80% oxygen saturation, 25° C., pH 7.2, 300-1000 rpm. After 14-23 hours, the vessel was chilled to 8°-12° C. and glycerol added to 10% final concentration. Cells were harvested by centrifugation. The concentrated cell paste was immediately frozen on dry ice and stored at -70° C. until use.
In addition, 1 L fermentations were carried out for biocatalyst production (as for Examples 1, 9 and 10). The process described above was followed with the following modifications. Adiponitrile, 10 mM, was used in the fermentations. Fermentations were stopped after 16-20 hours of growth at the 1 L stage. The cell suspension was chilled to 4° C., harvested by centrifugation and frozen at -60° C. following one wash with 15% glycerol in 0.05M phosphate buffer, pH 7.2.
Assay for Nitrile Hydratase Activity
The specific nitrile hydratase (NHase) activity (catalyst activity/gram cells) of 3L-G-1-5-1a-1 (ATCC 55736) whole cells was determined using a spectrophotometric assay. The assay protocol was to add 0.020 mL of a 10 mg/mL suspension of cells in 100 mM KH 2 PO 4 buffer (pH 7.0) to a 3 mL quartz cuvette containing 2.0 mL of 10 mM methacrylonitrile/100 mM KH 2 PO 4 buffer (pH 7.0) and a magnetic stir bar, followed by stirring the resulting suspension at 27° C. while recording the change in absorbance at 224 nm (ε=3400 L mol -1 cm -1 ). Nitrile hydratase activities are reported in IU/gram wet cell weight, where one IU (International Unit) of enzyme activity is equivalent to the amount of enzyme which will hydrolyze 1 micromole/minute of methacrylonitrile.
For Examples 2-8, the hydrolysis products of adiponitrile or 2-methylglutaronitrile were analyzed by high pressure liquid chromatography (HPLC) using techniques common to the art (Snyder et al., (1979), Introduction to Liquid Chromatography. John Wiley & Sons, NY). Specifically, Applicants used a refractive index detector and a Supelcosil LC-18-DB column (25 cm×4.6 mm dia.) (Supelco, Inc., Bellefonte, Pa., USA) with a mobile phase of 10 mM acetic acid/10 mM sodium acetate/2.5% methanol in water at a flow rate of 1.0 mL/min. In addition, for some examples, the hydrolysis products of adiponitrile were analyzed by gas chromatography (GC) using techniques common to the art (MeNair et al., (1965), Basic Gas Chromatography). Specifically, Applicants used an HP-17 crosslinked 50% PH ME silicone chromatography column in an HP 5890 gas chromatograph with FID detector. A temperature program of 180° C. for 1 min followed by a temperature increase of 10° C./min to a final temperature of 240° C. with 1 min hold was used to aid in peak resolution. Gas chromatography data are an average of duplicate determinations. Retention times were determined from authentic standards. N-Methylpropionamide was employed as an HPLC internal, instrument standard. Values for product yields and starting material recovery are all based on this internal instrument calibration standard.
EXAMPLE 1
5-cyanopentanamide production from adipontrile using Pseudomonas-derived Whole Cell Biocatalysts
Various Pseudomonas strains were grown on 10 mM adipontrile in PR Basal medium for 24 h and harvested by centrifugation. Wet cell pastes were frozen for storage. To test for biocatalyst reaction, 50 mg of frozen cell paste was resuspended in 1 mL of 50 mM pyrophosphate buffer, pH 7.5. Adiponitrile substrate was added to a final concentration of 100 mM and the cell suspensions were shaken at 200 rpm at 5° C. for 4-7 h. Cells were removed by centrifugation and the clarified supernatant was analyzed for the presence of 5-cyanopentanamide by gas chromatography. The following Pseudomonas strains were found to produce the desired product: P. putida 5B-MGN-2p (NRRL-18668), Pseudomonas sp. 3L-H-2-6-1p, P. putida 20-5-SBN-1b (ATCC 55735), P. putida 3L-G-1-5-1a-1 (ATCC 55736), P. chlororaphis B23 (FERM-B187), Pseudomonas sp. 3L-H-9-6-2p, and P. putida 2-H-9-5-1a.
EXAMPLE 2
5-cyanopentanamide Production Using Whole Cell Biocatalyst
Into a 15 mL polypropylene centrifuge tube was placed 9.08 mL of 20 mM KH 2 PO 4 /20 mM sodium butyrate buffer (pH 7.1) at 5° C., then 64 mg of 3L-G-1-5-1a-1 (ATCC 55736) wet cells and 0.853 mL (0.811 g, 7.50 mmol) of adiponitrile was added to the tube and the contents mixed on a rotating platform at 5° C. The resulting reaction volume contained 15 NHase IU/m. Aliquots (0.10 mL) were withdrawn at regular intervals, mixed with 0.010 mL of 1.0M HCl (to stop the reaction) and 0.100 mL of 0.200M N-methylpropionamide internal standard solution, and analyzed by HPLC to monitor the progress of the reaction. After 4 h, the HPLC yields of 5-cyanopentanamide and adipamide were 99.7% and 2.1%, respectively, with no adiponitrile remaining.
EXAMPLE 3
5-cyanopentanamide Production Using Immobilized Biocatalyst
The reaction described in Example 2 was repeated using 8.95 mL of 20 mM KH 2 PO 4 /20 mM sodium butyrate buffer (pH 7.1) at 5° C., 193 mg of 1 mm diameter, 10 weight % polyacrylamide gel beads containing 64 mg of 3L-G-1-5-1a-1 (ATCC 55736) wet cells, and 0.853 mL (0.811 g, 7.50 mmol) of adiponitrile. The resulting reaction volume contained 1.4 NHase IU/mL. Aliquots (0.10 mL) were withdrawn at regular intervals, mixed with 0.010 mL of 1.0M HCl (to stop the reaction) and 0.100 mL of 0.200M N-methylpropionamide internal standard solution, and analyzed by HPLC to monitor the progress of the reaction. After 6 h, the HPLC yields of 5-cyanopentanamide and adipamide were 94.4% and 1.6%, respectively, with 2.4% adiponitrile remaining.
EXAMPLE 4
Stability of Immobilized Biocatalyst for 5-cyanopentanamide Production
The reaction described in Example 3 was repeated using 8.55 mL of 20 mM KH 2 PO 4 /20 mM sodium butyrate buffer (pH 7.1) at 5° C., 600 mg of 1 mm diameter, 10 weight % polyacrylamide gel beads containing 200 mg of 3L-G-1-5-1a-1 (ATCC 55736) wet cells, and 0.853 mL (0.811 g, 7.50 mmol) of adiponitrile. The resulting reaction volume contained 4.7 NHase IU/mL. Aliquots (0.10 mL) were withdrawn at regular intervals, mixed with 0.010 mL of 1.0M HCl (to stop the reaction) and 0.100 mL of 0.200M N-methylpropionamide internal standard solution, and analyzed by HPLC to monitor the progress of the reaction. After 2 h, the HPLC yields of 5-cyanopentanamide and adipamide were 96.2% and 1.4%, respectively, with 0.8% adiponitrile remaining. The immobilized cell catalyst was recovered and reused in a total of 17 consecutive batch reactions (HPLC yields in Table 1, below); the remaining NHase activity at the end of reaction 17 was 0.94 IU/mL, corresponding to 28% of initial NHase activity. The productivity of the reaction, calculated as grams of 5-cyanopentanamide produced per gram dry cell weight of 3L-G-1-5-1a-1 (ATCC 55736), was ca. 322 g 5-cyanopentanamide/g dry cell weight (dry cell weight=0.25×wet cell weight; determined by lyophilization).
TABLE 1______________________________________rxn #time (h) % 5-cyanopentanamide % adipamide % adiponitrile______________________________________1 2 96.2 1.4 0.82 2.5 99.4 1.3 3.03 4 100.0 3.2 0.54 4 100.0 1.8 1.45 4 96.7 2.5 0.46 4 99.6 1.3 2.57 4 93.7 2.2 08 16 100.0 2.6 09 4 99.4 1.4 1.910 4 89.9 2.1 3.911 4 92.4 1.5 7.412 5 89.7 1.9 2.413 16 98.4 2.0 014 5 89.3 1.1 11.815 16 100.0 1.5 016 6.5 88.0 0.9 12.417 16 99.8 1.1 0.9______________________________________
EXAMPLE 5
Production of ω-cyanocarboxamides from 2-methylglutaronitrile Using Whole Cell Biocatalyst
To a 15 mL polypropylene test tube was added 1.14 mL (1.08 g, 10.00 mmol) of 2-methylglutaronitrile and 300 IU of 3L-G-1-5-1a-1 (ATCC 55736) cells. The total volume was adjusted to 10 mL with 20 mM KH 2 PO 4 buffer at pH 7.0 and 15° C. The contents was mixed on a rotating platform at 5° C. Aliquots (0.10 mL) were withdrawn at regular intervals, mixed with 0.010 mL of 1.0M HCl (to stop the reaction) and 0.100 mL of 0.075M N-methylpropionamide internal standard solution, and analyzed by HPLC to monitor the progress of the reaction. After 2 h, the HPLC yields of 4-cyano-2-methylbutyramide (4-CMBAM), 4-cyanopentanamide (4-CPAM), and 2-methylglutaramide (2-MGAM) were 60.3%, 32.5%, and 5.8%, respectively, with 0.2% 2-methylglutaronitrile (2-MGN) remaining.
EXAMPLE 6
Production of ω-cyanocarboxamides from 2-methylglutaronitrile Using Whole Cell Biocatalyst
The procedure described in Example 5 was repeated using 0.570 mL (0.542 g, 5.00 mmol) of 2-methylglutaronitrile, and 150 IU of 3L-G-1-5-1a-1 (ATCC 55736) cells. The total volume of the reaction mixture was adjusted to 10 mL with 20 mM KH2PO 4 buffer at pH 8.5 and 5° C. After 4 h, the HPLC yields of 4-cyano-2-methylbutyramide (4-CMBAM), 4-cyanopentanamide (4-CPAM), and 2-methylglutaramide (2-MGAM) were 64.3%, 26.2%, and 4.3%, respectively, with no 2-methylglutaronitrile (2-MGN) remaining.
EXAMPLE 7
Production of ω-cyanocarboxamides from 2-methylglutaronitrile Using Whole Cell Biocatalyst
1 mmole 2-MGN, 15 IU biocatalyst, pH 7, 5° C.
To a 15 mL polypropylene centrifuge tube was added 0.114 mL (0.108 g, 1.00 mmol) of 2-methylglutaronitrile (2-MGN), and 15 IU of 3L-G-1-5-1a-1 (ATCC 55736) cells. The total volume was adjusted to 10 mL with 20 mM KH 2 PO 4 buffer (pH 7.0) at 5° C. The contents were mixed on a rotating platform at 5° C. Aliquots (0.10 mL) were withdrawn at regular intervals, mixed with 0.010 mL of 1.0M HCl to stop the reaction and 0.100 mL of 0.075M N-methylpropionamide internal standard solution, and analyzed by HPLC to monitor the progress of the reaction. After 5 h, the HPLC yields of 4-cyano-2-methylbutyramide (4-CMBAM), 4-cyanopentanamide (4-CPAM), and 2 methylglutaramide (2-MGAM) were 68.8%, 27.0%, and 4.3%, respectively, with 0.5% 2-methylglutaronitrile (2-MGN) remaining.
EXAMPLE 8
Production of ω-cyanocarboxamides from 2-Methylglutaronitrile Using Whole Cell Biocatalyst
Various 2-MGN/biocatalyst loadings, pH 7, 5° C.
The procedure described in Example 7 was repeated, and both the amount of NHase activity and the amount of 2-methylglutaronitrile (2-MGN) added to a total 10 mL reaction volume were varied. Loadings of 5 mmol or greater 2-MGN are initially two phase reactions(as described in the detailed description of the invention). The yields of products and recovered 2-MGN for these reactions, as well as the reaction time for each reaction are reported in Table 2 below.
TABLE 2______________________________________mmol NHase2-MGN/ IU/ 4-10 mL 10 mL time CMBAM 4-CPAM 2-MGAM 2-MGNrxn rxn (h) (%) (%) (%) (%)______________________________________1.00 15 5.0 68.8 27.0 4.3 0.51.00 75 1.0 67.6 27.1 5.3 05.00 75 7.0 62.3 25.4 4.3 10.55.00 150 2.5 65.8 27.6 4.9 0.45.00 750 0.5 67.0 28.2 5.1 0.37.50 300 3.0 65.2 28.3 5.2 0.410.0 300 5.5 65.2 27.3 7.5 0.130.0 1000 25 63.7 28.6 6.1 2.250.0 1000 21 48.0 22.0 4.9 15.0______________________________________
EXAMPLE 9
Production of 5ocyanopentanamide from ADN Using Whole Cell Biocatalyst
200 mM ADN, 50 mg wet cells, 20-5-SBN-1b (ATCC 55735), pH 7.5, 30° C.
In a 20 mL glass vial, 50 mg wet cell paste of 20-5-SBN-1b (ATCC 55735) was resuspended in 1 mL of 50 mM pyrophosphate buffer, pH 7.5. Adiponitrile was added to a final concentration of 200 mM and the reaction mixture was shaken at 200 rpm at 30° C. for 4 h on a rotary shaker. Cells were removed by centrifugation and the recovered aqueous solution was diluted 1:10 with 10 mM 1,1-diethyl urea internal standard in acetonitrile and analyzed by gas chromatography. Of the ADN substrate, 5% of the original material remained and 93% had been converted to the only observed product, 5-cyanopentanamide.
EXAMPLE 10
Production of 5-cyanopentanamide from ADN Using Whole Cell Biocatalyst
400 mM ADN, 50 mg wet cells, 20-5-SBN-1b (ATCC 55735), pH 7.5, 30° C.
In a 20 mL glass vial, 50 mg wet cell paste of 20-5-SBN-1b (ATCC 55735) was resuspended in 1 mL of 50 mM pyrophosphate buffer, pH 7.5. Adiponitrile was added to a final concentration of 400 mM and the reaction mixture was shaken at 200 rpm at 30° C. for 4 h on a rotary shaker. Cells were removed by centrifugation and the recovered aqueous solution was diluted (1:20 with 10 mM 1,1-diethyl urea internal standard in acetonitrile) and analyzed by gas chromatography. Of the ADN substrate, 41% of the original material remained and 50% had been converted to the only observed product, 5-cyanopentanamide.
EXAMPLE 11
Production of 4-CMBAM and 4-CPAM from Whole Cell Biocatalyst
200 mM 2-MGN, 50 mg wet cells, 20-5-SBN-1b, pH 7.5, 30° C.
In a 20 mL glass vial, 50 mg wet cell paste of20-5-SBN-1b (ATCC 55735) is resuspended in 1 mL of 50 mM pyrophosphate buffer, pH 7.5. 2-Methylglutaronitrile (2-MGN) is added to a final concentration of 200 mM and the reaction mixture is shaken at 200 rpm at 30° C. for 4 h on a rotary shaker. Cells are removed by centrifugation and the recovered aqueous solution is diluted 1:10 with 10 mM 1,1-diethyl urea internal standard in acetonitrile and analyzed by gas chromatography. Of the 2-MGN substrate, 5% of the original material remains and 93% is converted to a mixture of the only observed products: 4-CMBAM and 4-CPAM.
EXAMPLE 12
Production of 4-CMBAM and 4-CPAM from Pseudomonas-based Biocatalysts
100 mM 2-MGN, 50 mg wet cells, pH 7.5, 5° C.
Various Pseudomonas strains are grown on 10 mM in PR Basal medium for 24 h and harvested by centrifugation. Wet cell pastes are frozen for storage. To test for biocatalyst reaction, 50 mg of frozen cell paste is resuspended in 1 mL of 50 mM pyrophosphate buffer, pH 7.5. 2-Methylglutaronitrile (2-MGN) substrate is added to a final concentration of 100 mM and the cell suspensions are shaken at 200 rpm at 5° C. for 4-7 h. Cells are removed by centrifugation and the clarified supernatant is analyzed for the presence of 4-CMBAM and 4-CPAM by gas chromatography. The following Pseudomonas strains are found to produce the desired products: P. putida 5B-MGN-2p (NRRL-18668), P. putida 3L-H-2-6-1p, P. chlororaphis B23 (FERM-B 187), and P. putida 2-H-9-5-1a. | Applicants have provided methods for obtaining aliphatic omega-cyanocaboximides of Formula I
NC--CH(R.sub.1)(CH).sub.n CH(R.sub.2)C(O)NH.sub.2
wherein
n=1-8 and R 1 or R 2 are either H or CH 3 ,
from dinitriles of Formula II
NC--CH(R.sub.1)(CH).sub.n CH(R.sub.2)CN
wherein
n=1-8 and R 1 or R 2 are either H or CH 3 ,
using biocatalysts which have regioselective nitrile hydratase activity and which are derived from members of the bacterial species Pseudomonas putida. | 8 |
This is a CONTINUATION of application Ser. No. 08/290,014, now U.S. Pat. No. 5,558,521, filed Aug. 12, 1994, which is a DIVISION of application Ser. No. 08/014,176, now U.S. Pat. No. 5,437,554, filed Feb. 5, 1993. U.S. Pat. No. 5,437,554 and U.S. Pat. No. 5,558,521 are hereby incorporated by reference in their entirety.
FIELD OF THE INVENTION
The present invention relates to a system for processing answers to test questions.
BACKGROUND OF THE INVENTION
The scoring of test answer sheets involves complex problems. These test answer sheets typically include a series of response positions such as, for example, "bubbles," ovals, or rectangles. A person taking a test would, for example, darken in an appropriate oval with a pencil to answer a multiple choice question. These test answer sheets may also include handwritten answers, such as essay or short answer questions. Systems for scanning and scoring the bubbles on such answer sheets are known in the art. Increased difficulties are encountered, however, when such answer sheets either include other types of answers, such as handwritten answers, or cannot be machine graded. For example, if the student has failed to include his or her name on the test answer sheet, the system may be unable to machine score the test answer.
The goals in scoring test answers that cannot be machine scored include efficiency and consistency. These test answer sheets are typically scored by test resolvers either by manually scoring the physical test answer sheet or scoring an electronic representation of the test answer sheet on a computer. Ideally, the scores provided by the various test resolvers for a particular test question should be consistent, since the scores are used in comparing performance of the students against one another. In addition, a test resolver should ideally work efficiently so as to maintain consistently high scoring rates. The test resolver should not have such a high scoring rate that the consistency or quality of scoring significantly declines; likewise, the test resolver should not have such a low scoring rate that the too few answer sheets are being scored. This manual scoring of test answer sheets, however, makes it difficult to monitor the consistency of scoring among the various test resolvers.
In many situations, test resolvers actually travel to a particular location so that all test resolvers may simultaneously score test answer sheets. Requiring the test resolvers to travel to a given location is inconvenient for the resolvers and expensive for those who administer the tests. Furthermore, tracking the performance of test resolvers against both their own performance and the performance of other resolvers can be very difficult with a manual scoring environment.
The process of resolving test questions is currently done manually, and this presents problems. A resolver is manually presented with the actual test answer sheets for scoring. This process is relatively inefficient, since the resolvers must score the answer sheets one at a time and in the order in which they are presented. Also, manual scoring systems do not have the capability to efficiently gather and categorize the test answers for subsequent analysis. Therefore, with a manual system it is very difficult to determine how teaching methods should be changed to decrease, for example, the number of incorrect answers.
A need thus exists for a system that promotes and achieves consistency and efficiency in scoring or resolving of test.
SUMMARY OF THE INVENTION
The present multiple test item scoring method facilitates the speed at which answers to test questions are processed. The method efficiently organizes, groups, and displays the answers to the questions such that a test resolver can simultaneously view multiple answers. In the method, a plurality of answers for test questions are received. The answers each comprise an electronic representation, such as a scanned image, of at least a portion of a test answer sheet. After receiving the test answers, the answers are organized into separate groupings, typically by resolution expertise of the test resolver. Finally, the method displays through a test resolver a particular one of the groupings such that the test resolver can selectively view and score the answers to the test questions related to the resolver's resolution expertise.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of a network that incorporates the present invention.
FIG. 2 is a block diagram of a portion of the network shown in FIG. 1.
FIG. 3 is a block diagram of the scanning configuration in the network of FIG. 1.
FIG. 4 is a block diagram of the server in the network of FIG. 1.
FIG. 5 is a flow chart of receiving and processing of test items.
FIG. 6 is a flow chart of multiple item scoring.
FIG. 7 is a flow chart of categorized (special) item reporting.
FIGS. 8-10 are a flow chart of collaborative scoring.
FIG. 11 is a flow chart of quality item processing.
FIG. 12 is a flow chart of resolver monitoring and feedback.
FIG. 13 is a flow chart of an on-line scoring guide system.
FIG. 14 is an example of a user interface for use with multiple item scoring.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following detailed description of the preferred embodiment, reference is made to the accompanying drawings which form a part hereof and in which is shown by way of illustration a specific embodiment in which the invention may be practiced. This embodiment is 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 structural or logical changes may be made without departing from the 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 by the appended claims.
HARDWARE CONFIGURATION
FIG. 1 illustrates an example of a hardware configuration for a network that incorporates the present invention. This configuration is shown as an example only; many different hardware configurations are available, as recognized by one skilled in the art, for implementing the software processing functions described below. The network shown comprises a mainframe computer 20 interfaced through a backbone token ring to a plurality of RISC servers 11, 12 and 13. Each RISC server is interfaced to a token ring that contains work stations and scanners. The RISC server 11 is connected in token ring 1 to scanners 14 and work stations 19. The RISC server 12 is connected in token ring 2 to scanner 15 and work stations 18. The RISC server 13 is connected in token ring 3 to scanners 16 and work stations 17. The mainframe computer 20 is also connected to a high capacity printer 22 and a low capacity printer 21 for printing reports of stored data within the system.
The system uses the scanners for reading in test answer sheets. These test answer sheets may comprise, for example, test forms with "bubbles" or ovals representing possible answers, handwritten essays, or other various types of written or printed information. After receiving the scanned test data, the system within the RISC servers can process those scanned test answer sheets to generate test items of interest from the answer sheets. A test item is, therefore, an electronic representation of at least a portion of a test answer sheet. The system may distribute these test items to the work stations for on-line scoring. A test scorer at a work station can then score the test item and enter a test score. The system receives the test scores via the network and the RISC servers and distributes the scores to an appropriate computer for subsequent printing and reporting; the appropriate computer may include, for example, the mainframe computer 20 or a server. The system may also transmit the test scores to, for example, a disk or telephone line.
FIG. 2 is a more detailed block diagram of a portion of the network shown in FIG. 1. As shown in FIG. 2, the scanning units shown in FIG. 1 typically comprise a scanner 25 interfaced to a computer 24 and personal computer (PC) 26. FIG. 3 shows a more detailed block diagram of a scanning unit. The scanner 25 contains a camera 31 for optically reading in a test answer sheet, and further contains optical mark recognition (OMR) logic 32 for processing the scanned data received from camera 31. The PC 26, preferably implemented with a high performance 486-level PC, contains a frame buffer 23 for receiving the scanned image data from the scanner 25.
The computer 24, preferably implemented with an HP 1000, is interfaced to the scanner 25 and PC 26 for controlling the operation of the scanning unit. The computer 24 is optional; the system may alternatively be configured such that all of the functionality of the computer 24 is within the PC 26. The computer 24 controls the scanner via the OMR logic 32 and thus controls when image data is scanned in and subsequently transferred to the PC 26. The PC 26 essentially acts as a buffer for holding the image data. The computer 24 further controls when the PC 26 will interrogate the image data for transmission to a server 27 for subsequent processing and scoring. The PC 26 can also electronically remove or "clip" an area of interest from the image data, which represents at least a portion of the scanned test answer sheets.
Examples of two systems for storing and extracting information from scanned images of test answer sheets are shown in U.S. Pat. Nos. 5,134,669 and 5,103,490, both of which are assigned to National Computer Systems, Inc. and are incorporated herein by reference as if fully set forth.
The server 27 receives the image data, which includes test items, and provides for processing and control of the image data. This portion, which may be a test item, is then distributed to the work stations 28, 29 and 30 for subsequent scoring. A test resolver (scorer) at the work station typically receives the test item, performs the scoring, and transmits the score to the receiving computer.
FIG. 4 is a block diagram of the hardware and software functions in a server in the network of FIG. 1. A scan control module 31 interfaces with the scanner PC 26 and receives the image data. The image data is stored in a raw item database 36. The central application repository (CAR) 33 typically stores document definitions and handling criteria. The document process queue 37 functions as a buffer into a main processing module 45 in server 27.
The main processing module 45 controls the processing of test items. It controls the transmission of test items to the work stations for scoring and the transmission of scores to the mainframe computer 20. The main processing module 45 also monitors the performance of the test resolvers to maintain consistent and efficient resolving of test items, as is explained below.
The main processing module 45 typically contains the following basic functions, which are controlled by system management module 32. A work flow module 38 receives image data from the database 36 and controls the flow of data into an edit process module 39. The edit process module 39 may perform machine scoring of the test items. For those test items which cannot be machine scored, or possibly for other test items, the system transmits such test items to the job build function 40. The job build function 40 determines what type of subsequent scoring is required for the test item and, for example, which work station will receive the test item. A job send module 41 receives the test item and transmits it to a router 42, which in turn transmits the test item to a send/receive communication module 43. Edit work module 34 and edit server module 35 control the flow of test items into and out of server 27. Incoming data, such as test answers from the work station, are transmitted through modules 34 and 35 to a job receive module 44. The job receive module transmits the data to the edit process module 39 for subsequent storage within the database 36.
SOFTWARE PROCESSING
FIG. 5 is a flow chart of typical scanning and processing of test and answer sheets. The document processing system receives the test answer sheets, or other documents, at step 50 and performs initial clerical preparation of the documents (step 51) for scanning at step 52. The system at step 52 scans the documents for OMR and other image data. The system may then process the OMR bubbles at step 53 and store the data in the work-in-process storage (WIP) at step 54. The system at step 56 can "clip" areas of interest from the scanned image. The step of "clipping" involves electronically removing, typically in software, a portion of the test item or scanned image. These "clipped" areas may comprise any portion of a test answer sheet; for example, a handwritten essay or selected response positions. The system may also receive image data directly from foreign sources, magnetic or electronic, and store the data in raw item database 36. Subsequent operations on the data are the same regardless as to the source of the data. After "clipping" areas of interest from the image, the system stores the test items at step 57 in the work-in-process storage 55.
The system waits at step 58 until it determines that a test item is ready to be resolved or scored. If multiple resolution items are present within the image data, as determined at step 59, then the system sends the test item to multiple item processing at step 63. Otherwise, the system performs other resolution processes on the data at step 60 and stores the result in work-in-process storage 55 at step 61. Other resolution processes may include, for example, machine scoring, raw key entry, and analytic resolving.
Analytic resolving or scoring may include, for example, map comparisons such as bit-mapped comparisons between two test items. The map comparisons allow a test resolver to compare, for example, the answers of a respondent over time to track the respondent's progress. For example, the analytic scoring may involve comparing two hand-drawn circles by the respondent to determine if the respondent's accuracy in drawing circles has improved over time. Analytic scoring may also include, for example, circling or electronically indicating misspelled words and punctuation errors in an answer such as an essay.
Multiple Item Scoring
FIG. 6 is a flow chart of typical multiple item processing. The system at step 64 typically first fetches a multiple item image from the work-in-process storage. The image is stored in a multiple item display memory 65 and a multiple item display storage 69 for subsequent display to a resolver. The system continues to receive multiple items until either the item display is full, as determined at step 66, or no more multiple items are present as determined at step 68. As long as the display is not full and additional multiple items are present, the system preferably scans the work-in-process storage at step 67 for additional items. When the multiple item display is full or no more multiple items are present, the system sends the compiled multiple items to a resolver at step 70 and displays the multiple test items on the resolver display 71.
The system typically transmits test items to a particular resolver based upon the resolver's resolution expertise. For example, a certain resolver may be assigned to score all of the test items relating to science questions. Resolution expertise may also comprise, for example, math, english, history, geography, foreign languages, or other subjects.
An example of an interface on the resolver display is shown in FIG. 14. The interface typically comprises a plurality of cells 74, with each cell containing one test item to be resolved. After displaying the multiple items in the cells of the resolver display, the system allows the resolver at step 72 to score the multiple items. A test resolver would typically indicate the score of the answers by using a "mouse," light pen, touch screen, voice input, or some other type of cursor control or input device.
In the example shown in FIG. 14, the correct answer is "four" and the incorrect answers are indicated by the shading. Alternatively, a resolver could indicate the correct answers. The advantage of the multiple item system arises from the simultaneous display of test items in the cells 74, which allows a test resolver to quickly score many test items and thus achieve a faster response time in comparison to the display and scoring of only a single test item at a time. Even the simultaneous display of two items increases response time. As the matrix of cells increases, the simultaneous display of test items achieves a significant increase in response time and resolver attention and focus.
After scoring or resolving, the system receives the results at step 73 for subsequent storage in work-in-process storage 55. A test resolver typically transmits the results of resolving all displayed test items in the cells as a single unit for batch processing.
Categorized Item Reporting
FIG. 7 is a typical flow chart of categorized (special) item reporting. Categorized item reporting allows the system to both group answers according to predefined categories and monitor processes used by the students or test-takers in arriving at a given answer. The categories in which test answers may be grouped include, for example, incorrect answers and correct answers within a curriculum unit within an instructional grouping and requested time frames; for example, all of the incorrect math answers in a particular instructor's class during the previous school year. Other groupings are possible depending upon the needs of the test resolvers and instructors who teach the material to which the test relates.
In addition, the system may merge an image of a test item with the corresponding score. In order to facilitate teaching of material to which the test relates, the system typically merges a test item representing an incorrect answer with the corresponding score. By reporting the actual test item, an instructor may gain insight into a thought process used by the student in arriving at the incorrect answer. Therefore, by having some knowledge of why a student answered a test question incorrectly, an instructor can take measures to change or modify teaching strategies to correct the situation.
The categorized item reporting normally comprises the following functions. The system at step 75 scans the work-in-process storage for items that are ready to be reported. If test items are ready for reporting, as determined at step 76, the system processes the data at step 77 for generating an appropriate report of the data. At step 78, the system scans the central application repository for definitions of categorized (special) items. As special items are available for reporting, as determined at step 79, the system retrieves the special items at step 80 and can merge it at step 81 with other report information, such as the corresponding test items, as explained above. The system then distributes a report at step 82, which can be a printed report.
Collaborative Scoring
FIGS. 8-11 are a flow chart of a typical collaborative scoring system. The collaborative scoring system provides for functions to achieve fairness and objectivity in resolving of test items. The collaborative scoring, for example, allows two resolvers to score the same item and, if the answers are not within a certain predefined range, provides for subsequent processing to resolve the discrepancy.
The system at steps 83 and 84 determines if items are available for scoring. At step 85, the system receives collaborative scoring requirements from the database and determines at step 86 if collaborative scoring is required. Examples of collaborative scoring requirements are illustrated below. If collaborative scoring has been specified, the system retrieves the item to be scored from the work-in-process database at step 87 and sends the item to resolvers 1 and 2 at steps 88 and 91.
The system is further able to choose resolvers according to selection criteria at steps 89 and 90. The selection criteria of the resolvers for scoring answers may include, for example, race, gender, or geographic location. The ability of the system to assign test resolvers to score particular test items provides the basis for increased fairness and consistency in the scoring of tests. For example, the system may assign test resolvers to test items based on the same racial classification, meaning that the test resolver has the same racial classification as the student or respondent whose test the resolver is scoring. The system may also assign test resolvers to test items based on a different, forced different, or preferred blend of classifications. The system monitors consistency in scoring based on the selection criteria and, more importantly, can change the selection criteria to ensure consistent and fair scoring of test items.
FIG. 9 is a flow chart showing additional typical functions of the collaborative scoring. At steps 92 and 93, the system displays the items to resolvers 1 and 2 for scoring. The system may further track the average scores of resolvers and not send the same test item to two resolvers who have provided average scores within a predefined range. This also helps to achieve consistency in scoring. For example, if two scorers each have provided high average scores in the past, as determined by the system, these two scorers should preferably not be collaboratively scoring the same test items, since it could result in "inflated" scores for particular test items.
The system records the scores from resolvers 1 and 2 at steps 94 and 95, respectively, and stores such scores in a temporary storage 96. At step 97, the system compares the scores according to criteria specified in the central application repository. Such criteria may include, for example, requiring that the scores be within a predefined percentage of each other. If the scores meet the criteria as determined at step 98, the system records the score in the work-in-process database at step 46. Otherwise, if the scores do not meet the criteria, the system determines at step 99 if the scores of the resolvers must agree. If the first two resolvers scores do not need to agree, then the system preferably transmits the test item to a third resolver to "cure" the discrepancy in the first two scores. At step 100, the system determines if the third resolver should see the first scores.
FIG. 10 shows additional typical processing of the collaborative scoring. If the original resolvers 1 and 2 must agree on a score, then the system executes steps 101-105. The system then typically first displays to each resolver the other resolver's score at steps 101 and 102 so that each resolver can see the score determined by the other resolver. At step 103, the system establishes a communication between the two resolvers. Such a communication link may be, for example, an electronic mail link so that the scorers can exchange information regarding the reasoning behind the score provided. At step 104, the resolvers work together to determine a single agreed-upon score for the test item. The system may prevent the resolvers 1 and 2 from receiving another test item until they have entered an agreed-upon score for the previous test item. Finally, at step 105, the system stores the agreed-upon score in the work-in-process database.
Instead of allowing the resolvers to work together to record an agreed-upon score, the system may optionally record either a greater value of the first and second test scores, a lower value of the first and second test scores, or an average value of the first and second test scores.
If the collaborative scoring criteria specifies that the third resolver should arbitrate the discrepancy and determine a score, then the system displays scores from the resolvers 1 and 2 at step 106 for resolver 3. The third resolver (resolver 3) then typically enters a score for the teat item at step 107, and the system records the score in the work-in-process database at step 108.
If the collaborative scoring requirement specifies that the third resolver should not see the first two scores, then the system executes steps 109-111. At step 109, the system displays the test item for the third resolver. The third resolver then typically enters a score at step 110, and the system records the score in the work-in-process database at step 111.
Quality Items
FIG. 11 is a typical flow chart of the use of quality items in the scoring process. The system can use quality items to check and monitor the accuracy of the scoring for selected test resolvers in order to maintain consistent and high quality scoring of test items. At step 112, the system determines or receives the quality criteria. The quality criteria may be, for example, a predetermined test item with a known "correct" score.
The system then waits for a scheduled quality check at step 113. At the quality check, the system, at step 114, sends the known quality item to the scheduled resolver. At step 116, the system updates the resolver's quality profile based on the evaluation at step 115. If the resolver should receive a quality result, as determined at step 117, the system displays the quality profile to the resolver at step 118. At step 119, the system sends the quality profile to a manager for subsequent review. At step 120, the system takes action required to assure scoring accuracy.
Resolver Monitoring and Feedback
FIG. 12 is a flow chart of typical resolver monitoring and feedback. The primary factors in monitoring performance typically include: (1) validity; (2) reliability; and (3) speed. In monitoring these factors, the system promotes repeatability of scoring. These factors may be monitored by tracking a resolver's performance against past performance of the resolver or against some known goal.
Validity is typically measured by determining if a particular resolver is applying the scoring key correctly to test items or, in other words, scoring test items as an expert could score the same items. Reliability is typically measured by determining if a particular will resolve the same test item the same way over time (providing consistent scoring). Speed is typically measured by comparing a resolver's scoring rate with past scoring rates of the resolver or other scoring rates, such as average scoring rates or benchmark scoring rates.
At step 121, the system typically continually monitors the resolver's performance and updates the performance. Monitoring the resolver's performance may include, as explained above, monitoring the resolver's validity, reliability, and speed in resolving test items. The system periodically, according to predefined criteria, performs performance checks of the test resolvers. Predefined criteria may include, for example: a time period; recalls (how often a resolver evaluates his or her own work); requesting help; the number of agreements among multiple resolvers; the amount of deviation between the resolver's score and a known score, which may be determined using quality items; the frequency of these deviations; the speed at which a resolver enters a response during resolving of test items; the length of time between scores entered by a test resolver; a test resolver's previous scoring rate, an average scoring rate of a test resolver; average scoring rates of other test resolvers; or some predetermined benchmark scoring rate.
At step 122, the system determines whether it is time for a scheduled performance check according to the predetermined criteria. If it is time for a performance check, the system at step 123 compares the resolvers' current performance, as determined at step 121, with the stored performance criteria. At step 124, the system determines if there is a discrepancy in the resolver's performance according to the predetermined criteria. For example, the system may determine if the resolver's current scoring rate is within a predefined percentage of the average scoring rate in order to ensure efficient scoring by the test resolver. If there is no discrepancy, the system returns to monitoring the resolver's performance. In addition, the system may store the resolver's current performance values for later processing. Otherwise, the system reports the discrepancy at step 125.
At step 126, the system determines if it should recommend a break in scoring to the resolver. If according to predetermined performance criteria, the system should recommend a break in scoring, then the system signals the resolver at step 128 to halt scoring. Predefined performance criteria may include, for example, deviations in the resolver's validity, reliability, or speed of resolving test items. Examples of predefined performance criteria are provided above with respect to the monitoring of resolvers' performance.
When the resolver stops scoring, the system may provide the resolver with the option of requesting diversionary activities. Diversionary activities are designed to provide the test resolver with a rest period and "break" from scoring to increase efficiency. Examples of diversionary activities include computer games and cross word puzzles. If the resolver has requested such diversionary activities, as determined at step 129, then the system transmits a diversionary activity to the resolver at step 130. Otherwise, the system returns to monitoring the resolver's scoring rate when the resolver resumes the scoring.
If the system at step 126 does not recommend a break in scoring based on the discrepancy, then the system may optionally provide the resolver with diversionary activities as determined at step 127. If the resolver should receive the diversionary activities, then the system sends such activities to the resolver at step 130. Otherwise the system returns to monitoring the resolver's scoring rate.
On-Line Scoring Guide
FIG. 13 is a flow chart of a typical on-line scoring guide system. The on-line scoring guide increases scoring efficiency by allowing the resolver to request scoring rules in order to assist in scoring a particular test item. In response to the request, the system displays scoring rules corresponding to a test question for the test item currently displayed to the resolver. A resolver may thus quickly have specific scoring rules available on-line while scoring test items. This promotes scoring efficiency and reduces unnecessary break times resulting from determining how to score a particular test item.
At step 131, the system sends a test item to a resolver for scoring and displays the test item at step 132. If the resolver has requested scoring rules, as determined at step 133, then the system interrogates a stored scoring guide to locate scoring rules that correspond to a test question for the test item currently displayed to the resolver. The system retrieves those particular scoring rules at step 135 and displays them to the resolver at step 136. The system preferably uses a multi-tasking environment in order to simultaneously display the scoring rules and the test item. At step 134, the system waits for the resolver to score the test item. At step 137, the system stores the test score entered by the resolver into the work-in-process storage.
As described above, the present invention is a system that processes test items. The various functions used in processing the test items promote efficient, high quality, and consistent scoring of test items.
While the present invention has been described in connection with the preferred embodiment thereof, it will be understood that many modifications will be readily apparent to those skilled in the art, and this application is intended to cover any adaptations or variations thereof. For example, a different hardware configuration may be used without departing from the scope of the invention and many variations of the processes described may be used. It is manifestly intended that this invention be limited only by the claims and equivalents thereof. | A method for increasing the speed at which test answers are processed. The method receives electronic representations of test answers and organizes the test answers into separate groupings. The method next displays a particular grouping of test answers to a test resolver so that the resolver can score the test answers. In displaying the answers, the method uses a matrix of cells and displays one test answer in each of the cells. The test resolver can thus simultaneously view multiple test answers, which facilitates efficient scoring of the answers. | 8 |
The invention relates to a plug-in module for controllers of mobile working machines, in particular of extraction machines, for aboveground or underground mining, having a housing, having a connection plug which is exposed on one side of the housing and can be detachably connected to a bus board of a controller, having an electronics board which is arranged in the housing, and having at least one plug socket, which is exposed on the housing, for connecting actuators or sensors or the like for the working machine to the plug-in module.
BACKGROUND OF THE INVENTION
Mobile working machines are used for mining mineral deposits such as coal seams, ore deposits, brown coal deposits, but also for mining quarries, salt deposits or the like, all the control electronics containing all the functions required for semiautomatic or automatic execution of the working processes in said mobile working machines being associated with one or more controllers which is/are arranged “onboard” the mobile working machine. In mobile working machines, all the structural parts and components which are to be used are, in principle, subject to restrictions in terms of size and weight, it being necessary, at the same time, on account of the mobility, to provide for adequate protection against vibrations since vibrations occur on account of the movement of the working machine in addition to the actual working movement. In mining machines, which form the preferred field of application of the present invention, it may additionally be necessary to make provision for all the control electrics and control electronics to be constructed and designed to be intrinsically safe in order to reliably prevent ignition sparks or ignition voltages being created in areas which are subject to explosion hazards.
Due to the increasing trend for automation, greater demands are increasingly being made on the onboard control system of the mobile working machine and diagnostics options, in particular remote diagnostics options, are being demanded for improved operability. In order to establish a fully automatic manner of operation, the control electronics also have to be capable of being able to evaluate sensors of measurement and diagnostics systems and sensors for exploring the area surrounding the mobile working machine and, at the same time, to drive a wide variety of actuators.
SUMMARY OF THE INVENTION
An object of the invention is to provide a plug-in module for controllers of mobile working machines which is suitable for use with a wide variety of actuators or sensors or can be adapted for this purpose and, at the same time, can be used advantageously in an onboard controller of a mobile working machine.
According to the invention, this object and others are achieved in that the housing consists of a box with a preferably rectangular housing wall arrangement comprising a front wall, a rear wall, two side walls and a base plate which is provided with a cutout for the connection plug for connecting the plug-in module to a bus board of a controller, and in that the electronics boards are connected to two end boards and two side boards to form a board box, with the board box being arranged in the interior of the housing, the connection plug being electrically conductively connected to one end board of the board box and the at least one plug socket being electrically conductively connected to the opposite end board, and the plug socket being mechanically coupled to the housing by means of a strain-relief clip. The effects of connecting a plurality of electronics boards to form a board box are firstly that individual boards with different functions can be connected to one another in a relatively simple manner and, at the same time, a relatively flexurally rigid control electronics system which is highly insusceptible to faults caused by vibrations and impact loads can be provided for the plug-in module. For its part, the strain-relief clip between the plug socket and the plastic housing, together with the box-like structure of the electronics boards, ensures a sufficient degree of robustness of the overall structure since tensile and compressive loads on the plug socket can be diverted into the housing via the strain-relief clip without damaging the electronics in the housing.
In an especially advantageous embodiment, the housing consists of a plastic housing with a preferably integrally formed base plate. In the case of a plug-in module according to the invention, a plastic housing provides a relatively lightweight housing which, at the same time, is advantageously resistant to environmental influences such as moisture, dirt and the like, and can be produced in a relatively cost-effective manner on a large scale. The use of a plastic housing instead of a solid stainless steel housing, as has been used to date in mining in particular, ensures considerable standardization in terms of weight and size.
According to a particularly advantageous embodiment, the strain-relief clip consists of a U-shaped bent sheet-metal part, in particular composed of metal such as stainless steel. The bent sheet-metal part can be connected to the plastic housing in a particularly simple manner by virtue of the U-shaped design of the bent sheet-metal part by, for example, a screw connection being established between the end pieces of the bent sheet-metal part and the side walls of the wall arrangement of the plastic housing. It is particularly advantageous when the bent sheet-metal part has bent end limbs and a central limb, with the central limb being provided with at least one receiving hole for a plug socket and the end limbs being connected, for example screwed, to the side walls of the plastic housing. For the purpose of further minimization, it is particularly advantageous when a plurality of receiving holes, in particular two receiving holes for fixing a plurality of, in particular two, plug sockets are provided in the central limb. When there are two plug sockets, two sensors or actuators can be connected to each plug-in module, it being possible to meet all the requirements of intrinsic safety relatively easily with round plug sockets in particular.
In order to achieve simple mounting, it is especially advantageous when the plug socket or sockets is/are fixed directly or indirectly to the central limb of the tensioning clip by means of a screw connection. For the purpose of direct screw connection, each receiving hole can be provided with a thread to which a threaded connection piece on the plug socket can be directly tightly screwed. For the purpose of indirect screw connection, each plug socket can be provided with a socket extension having an external thread, said socket extension being passed through the receiving hole from one side, with a nut being screwed onto the threaded portion from the other side in order to secure the plug socket to the central limb in a rotationally fixed and tension-resistant manner. As an alternative or in addition, the central limb can be provided with one or more windows for signal indicator means in order to indicate, for example using LEDs, whether an operable actuator is connected to the plug socket and/or whether this actuator is being driven at the current time.
In order to additional reinforce the plug-in module, it is advantageous when the side walls of the plastic housing have associated L-shaped lugs which can be or are connected to the strain-relief clip and extend as far as the base plate of the housing or plastic housing. In the most simple refinement, the L-shaped lugs can be loosely fitted from outside and then be connected to the fixing means for the bent sheet-metal part and to the plastic housing by way of the said fixing means for the bent sheet-metal part. The housing or plastic housing and lugs are advantageously fixed by way of fixing means for tightly screwing the plug-in module to the bus board or base plate. The L-shaped lugs on the one hand and the bent sheet-metal part on the other then form an extremely stable fixed and shielded arrangement for the plug sockets and the electronics boards in the mounted state. According to an especially advantageous refinement, the base plate projects laterally beyond the side walls by way of a fixing web, and the fixing web and the lug limb of the respective lug are provided with a passage for a fixing means for locking the plug-in module to the bus board.
In order to avoid incorrect mounting, the connection plug which is associated with the base plate can expediently be arranged asymmetrically offset in relation to a side wall, the front wall or the rear wall of the housing or plastic housing. Incorrect mounting can also be additionally or alternatively prevented by adjustment pins if they allow the plug-in module to be mounted on the bus board only in a specific position.
The adjacent end boards and side boards which are connected to form a board box are preferably in each case electrically connected to one another by means of at least one flexible conductor track. The adjacent end boards and side boards are preferably only plugged to one another by, for example, the end edges of the side boards being provided with locking projections which are passed through slots in the end boards and bolted.
In order to avoid moisture, dirt and other environmental influences entering the interior of the plastic housing, a seal is preferably incorporated between the base wall-end end board of the board box and the base plate of the plastic housing, and/or a seal, which surrounds the connection plug, is arranged on the outer face of the base plate of the plastic housing. Further preferably, the plug sockets can protrude beyond the upper edge of the plastic housing and the interior of the plastic housing is filled with encapsulation compound. By filling the entire plug-in module with encapsulation compound, the plug-in module can also satisfy the requirements of a protection class such as IP65 or IP68, with the mechanical stability of the plug-in module being increased by the encapsulation compound at the same time.
These and other objects, aspects, features, developments and advantages of the invention of this application will become apparent to those skilled in the art upon a reading of the Detailed Description of Embodiments set forth below taken together with the drawings which will be described in the next section.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a plan view of a controller having a bus board with six plug-in spaces, with plug-in modules according to the invention being plugged into three plug-in spaces;
FIG. 2 shows a perspective view of a preferred refinement of a plug-in module according to the invention;
FIG. 3 shows an exploded illustration of the plug-in module from FIG. 2 ;
FIG. 4 shows a longitudinal section through the plug-in module from FIG. 3 ; and
FIG. 5 shows the plug-in module from FIG. 2 in section parallel to the side walls.
DETAILED DESCRIPTION OF EMBODIMENTS
Referring now to the drawings wherein the showings are for the purpose of illustrating preferred and alternative embodiments of the invention only and not for the purpose of limiting same, FIG. 1 shows a highly simplified schematic plan view of a controller in which the plug-in modules according to the invention are preferably used and which is designed, in particular, for use on mobile working machines which are used in areas which are subject to explosion hazards. The controller 1 comprises a base plate 2 , for example composed of stainless steel, on which a backplane or bus board 3 with, in this case, six plug-in spaces 6 is fixed in a suitable manner. The bus board 3 is, in addition to the plug-in spaces, provided with conductor tracks and electronics elements (not illustrated) and the individual plug-in spaces 6 are connected to the terminal block 4 which, in this case, is arranged centrally on one side of the base plate 2 of the controller 1 . In this case, the terminal block 4 has three round plugs 5 , 5 A, it being possible for the round plugs 5 , 5 A to be designed, for example, in such a way that one round plug 5 forms a network input, one round plug 5 forms a network output and a third round plug 5 A forms a power supply connection for electrical voltage, in particular an intrinsically safe DC voltage. Plug-in modules 10 , 10 A, 10 B according to the invention are already inserted into three of the plug-in spaces 6 in the bus board 3 of the controller 1 , with, in the exemplary embodiment shown, the three inserted plug-in modules 10 , 10 A, 10 B largely having the same structure but being equipped with different functionalities and having slightly different indicator devices or connection plugs. Each plug-in space 6 is preferably provided with a plurality of non-uniformly distributed adjustment holes 7 in order to avoid incorrect mounting of a plug-in module 10 , 10 A, 10 B. The structure of the plug-in modules 10 , 10 A, 10 B will now be explained with reference, in particular, to FIGS. 2 to 5 in which the plug-in module 10 is illustrated in detail.
The plug-in module 10 has an integral plastic housing 11 which is preferably produced using an injection-moulding process and has a front wall 12 , a rear wall 13 , two side walls 14 and also an integrally formed base plate 15 , and the plastic housing is preferably designed in the form of a box. The base plate 15 is provided with a cutout 16 within which a connection plug 17 is freely accessible in such a way that the connection plug 17 is held in the plug-in space ( 6 , FIG. 1 ) which is formed on the controller ( 1 , FIG. 1 ) when the plug-in module 10 is connected to the controller. The connection plug 17 is preferably arranged in a manner asymmetrically offset in relation to the front wall 12 or the rear wall 13 , so that the plug-in module 10 can be mounted on the controller with only one orientation so as to establish a plug-type connection between the connection plug 17 and the associated plug-in space. In order to avoid incorrect mounting and, at the same time, to reliably establish a plug-type connection, integrally formed adjustment pins 18 , which can be inserted into the adjustment holes ( 7 , FIG. 1 ) for each plug-in space in an interlocking manner, can be formed on the base plate 16 .
In the exemplary embodiment shown, the connection plug 17 is firmly soldered to a lower end board 21 which, together with two side boards 22 and a further end board 23 , forms a board box 24 which can be arranged entirely within the interior 19 of the plastic housing. As a result, the entire electronics system is provided with a robust and flexurally rigid structure on account of the box-like structure of the said board box with end boards 23 which are reinforced by means of the side boards 22 . The side boards 22 and the end boards 21 , 23 are plugged to one another to form the board box 24 , for which purpose the side boards 22 have projections which are passed through slots in the end boards and can be bolted to the protruding projection portion. The connection contacts of two plug sockets 25 are connected, in particular soldered, to the second, upper end boards 23 which are composed of metal round plug sockets in the exemplary embodiment shown. In each case adjacent boards, for example the lower end boards 21 and the side boards 22 or the side boards 22 with the upper end board 23 , are connected to one another by means of flexible conductor tracks (not shown), and therefore all the control and switching electronics which are integrated in the plug-in module 10 can be arranged in a manner distributed over the printed circuit boards 21 , 22 , 23 with any desired functions. On account of this design, it is also possible to fit identical end boards 21 , 23 with different side boards 22 in order to adapt each plug-in module to its functionalities in a cost-effective manner. Furthermore, indicator elements 26 for simple monitoring functions or signal blocks 27 for visualizing text or values can be connected to the printed circuit board 23 for the plug sockets 25 .
FIGS. 3 to 5 clearly show that the two plug sockets 25 are fixed to a U-shaped bent sheet-metal part 30 which, for fixing the round plugs 25 , is provided with two receiving holes 31 which are oval in this case. In the exemplary embodiment shown, the round plugs 25 are screwed only indirectly to a central limb 32 of the bent sheet-metal part 30 and each round plug 25 has a threaded extension 28 onto which a fixing nut 29 is screwed from the other side of the bent sheet-metal part 30 in order to secure the round plugs 25 to the bent sheet-metal part 30 in a tension-resistant and rotationally fixed manner. The central limb 32 of the bent sheet-metal part 30 merges with a respective end limb 33 which is bent at a right angle, with the bent sheet-metal part 33 being screwed to the side walls 14 of the plastic housing 11 via threaded holes 34 in the end limb 33 and by means of fixing screws 35 in the mounted state. Since the connection plugs 25 are screwed to the bent sheet-metal part 30 and the bent sheet-metal part 30 is, in turn, screwed to the plastic housing 11 , the bent sheet-metal part 30 can form a strain-relief clip which prevents forces which could be exerted on the plug-in modules by cables which are connected to the connection plugs 25 from being able to be transmitted to the electronics boards. The central limb 32 is provided, centrally between the two receiving holes 31 , with a window 36 , which is rectangular in this case, so that the indicator elements 26 , 27 are exposed, so that they are visible, on the upper face of the plug-in module 10 .
In order to lend additional rigidity to the plastic housing 11 , L-shaped connection lugs 40 are loosely screwed from the outside to the two end faces 14 by means of the fixing screws 35 . In each case one bent, short lug limb 41 of the lugs 40 has a passage hole 42 for a locking screw by means of which the plug-in module 10 can be screwed to the base plate ( 2 , FIG. 1 ) of the controller. The base plate 15 of the plastic housing 1 projects laterally beyond the side walls 14 of the plastic housing 11 by way of fixing webs 15 A, with the lug limbs 41 being positioned parallel in front of the fixing webs 15 A in the mounted state. The long limb portion of the connection lugs 40 has a passage hole for the fixing screw 35 . In this way, all tensile forces can be introduced into the base plate of the controller directly via the strain-relief clip which is formed by the bent sheet-metal part 30 , and the connection lugs 40 and all the internal fittings in the plug-in modules 10 , in including the plastic housing, are not subjected to the action of these forces in the mounted state.
In the mounted state, the plug sockets 25 project, as can be seen in FIGS. 4 and 5 , beyond the upper face of the side walls 14 and also the front wall 12 and the rear wall 13 of the plastic housing 11 . A seal 45 is arranged beneath the base plate 15 of the plastic housing 11 , the said seal surrounding the cutout 16 and, in this respect, also the connection plug 17 , in order to prevent the ingress of moisture in the mounted state. The entire interior 19 of the plug-in module 10 is preferably filled with an encapsulation compound or the like in order to additionally reinforce the plug-in module 10 and, at the same time, to meet the requirements of protection classes such as IP65 or IP68.
The plug-in module 10 A shown in FIG. 1 has the same internal structure as the plug-in module 10 but differs, for example, in terms of the electronics arranged on the boards and by virtue of the selection of different indicator elements 26 A, in this case three indicator elements which are identical to one another, which each extend through a separate window in the strain-relief clip 30 A. The plug-in module 10 B also has the same structure as the plug-in module 10 , in particular within the housing 11 B, but differs, for example, by virtue of the electronics arranged on the boards and on account of the presence of only one flat plug 25 B which extends through a single window in the strain-relief clip 30 B.
Numerous modifications, which are intended to be covered by the scope of protection of the appended claims, are apparent to a person skilled in the art from the above description. Instead of round plugs and/or the indictor means shown, a flat plug can be arranged on the upper face of the plug-in module and/or the indicator elements can be dispensed with or designed differently, in particular when the plug-in module is not designed for intrinsically safe operation. A plug-in module can also have fewer or more than two plug sockets. The housing can also be composed of materials other than plastic, even though a plastic housing forms the preferred refinement.
Further, while considerable emphasis has been placed on the preferred embodiments of the invention illustrated and described herein, it will be appreciated that other embodiments, and equivalences thereof, can be made and that many changes can be made in the preferred embodiments without departing from the principles of the invention. Furthermore, the embodiments described above can be combined to form yet other embodiments of the invention of this application. Accordingly, it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation. | A plug-in module for controllers of mobile working machines, having a housing, a connection plug, electronics boards and at least one plug socket for connecting actuators or sensors. The housing being formed by a box with a front, rear and side walls as well as a base plate comprising a cutout for the connection plug, and in that the electronics boards are forming a board box by connecting two end boards and two side boards, with the board box being arranged in the interior of the housing, and with the plug socket being mechanically coupled to the housing by a strain-relief clip. | 7 |
This is a Continuation of International Appln. No. PCT/GB96/01239 filed May 23, 1996 which desingnated the U.S.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to methods and apparatus for the filtration of micro-organisms from a sample and the culture of the micro-organisms in situ on the filter used in the filtration.
2. Description of the Related Art
As discussed in EP0150775, it is known to capture micro-organisms for culture by the membrane filtration of a sample through a sterile membrane placed on a porous holder. After filtration the membrane may be removed and deposited on to a gelatinous culture medium contained in a Petri dish. The Petri dish may then be incubated at a suitable temperature for the time necessary for the micro-organisms to be able to develop and multiply sufficiently to form colonies visible to the naked eye to permit them to be identified and counted.
Even slightly contaminated samples may be evaluated as the micro-organisms are concentrated on the membrane, and it is possible to filter a significant volume of sample to collect a sufficient number of micro-organisms. However, disadvantages which arise in this method are first that the colonies can run out of nutrients in the local area of the agar medium, which in circumstances where there are large numbers of bacteria on the membrane can result in suppression of growth of individual colonies. Also, care must be exercised in placing the membrane filter on the culture medium to avoid entrapping any air bubbles between the culture medium and the membrane which would prevent contact between the culture medium and a portion of the surface of the membrane, thereby opposing diffusion of the culture medium and inhibiting micro-organism development.
In an alternative procedure, it has been proposed to place the membrane containing the filtered bacteria on to a filter paper wick to conduct nutrient medium to the membrane. However, the amount of medium added to the wick has to be carefully controlled in order that the membrane filter does not become too moist such that confluent growth is observed rather than the growth of individual colonies.
Also , these techniques generally involve the transfer of the membrane from the filtration apparatus to the culturing operation and this additional step has the potential to introduce contamination as the membrane is exposed to the air. It also means that culturing cannot start until the samples have travelled from the sampling site to the laboratory, which take a period of several hours.
As further disclosed in EP-B-0150775, it has been proposed to remedy some of these inconveniences by the use of apparatus consisting of a sterile box with circular elements nested into one another and a removable cover. The box includes an inlet and an outlet disposed on both sides of a holder on which an absorbent pad and a filtration membrane lie, clamped at the periphery of the holder by one of the circular elements. After filtration, a culture medium is introduced through the outlet, that is counter currently to the filtration operation, to saturate the absorbent pad. The box can be placed in an incubator to permit the collected micro-organisms to develop. This avoids the need for any transfer operation after filtration and before culturing and permits samples to be directly taken on the site at which the liquid is collected. However, as stated in EP-B0150775, this method still has serious draw-backs. In particular, the membrane diameter increases when the membrane becomes wetted and since the membrane and the absorbent pad, which are clamped at their periphery to the sterile box, are kept dry prior to use, upon filtration of the sample the wetting of the pad and the membrane may cause the membrane filter to part from the absorbent pad. This will prevent contact between the membrane and the pad saturated with the culture medium and thus disturb the development of the micro-organisms upon incubation.
EP-B0150775 proposes an elaborate solution to this problem which involves sealing a membrane filter across the bottom of a tubular holder such that the holder can be pressurised with air to bulge the membrane outwardly prior to mating it against the surface of a gelled nutrient medium in a cup. This reintroduces the danger of contamination of the system during the manipulation involved. Any micro-organism contamination of the interface between the nutrient medium and the filter membrane is likely to interfere with the growth of the micro-organisms on the opposite face of the membrane filter. Furthermore, the apparatus depicted in EP-B0150775 is unduly elaborate and cumbersome to manufacture and to use.
We have now appreciated that the problem outlined in EP-B0150775 is capable of a substantially simpler solution which avoids reintroducing the draw-backs inherent in the earlier prior art.
Accordingly, the present invention now provides a method for filtering micro-organisms from a sample and culturing the micro-organisms, which method comprises filtering a sample containing micro-organisms through a membrane filter in a filter holder in which holder the membrane filter is supported on an absorbent support, and then supplying culture medium to the micro-organisms on the membrane filter in the filter holder by absorbing the medium into the absorbent support, characterised in that the absorbent support is maintained in an expansible compressed state against the membrane filter.
By virtue of the absorbent support being compressed against the membrane filter, if expansion of the membrane filter takes place any tendency of the membrane filter to expand away from the absorbent support is countered by the absorbent support being able to expand and maintain contact with the membrane filter.
There is therefore no need to remove the membrane filter from the absorbent support after the filtration operation and to mate the surface of the membrane filter against a gel of nutrient medium. Instead, sterile nutrient medium may be applied directly to the compressed absorbent support in the filter holder.
The absorbent support is preferably of reticulated foam. Suitable polymer foams are available made from a wide variety of plastics materials such as polyethers, polyesters, polypropylene, polyvinylchloride and polyurethanes. Preferred polymer foams are of from 50 to 200 ppi (pores per inch) (equivalent to 20 to 80 pores per centimeter) e.g. Approximately 100 ppi (equivalent to 40 pores per centimeter).
Suitably, the absorbent support takes the form of a block of such reticulated foam having a free uncompressed thickness of 0.5 to 3 cm, e.g. about 1 cm and presenting a major face on which the membrane filter may be placed directly or, more preferably, with a layer of a wick material such as filter paper between the membrane filter and the absorbent support.
Preferably, the absorbent support is compressed to a is thickness of from 7/8ths to 1/10th of its free uncompressed thickness. The degree of compression need not be uniform over the whole area of the absorbent support. For instance, if the compression is actually applied at the edges of the absorbent support, the compression in the centre of the absorbent support may well be significantly less.
Preferably, between the membrane filter and the absorbent support of reticulated foam there is an intermediate compression spreading support layer transmitting compression forces applied to the edges of the assembly of the membrane filter, compression spreading layer and absorbent support of reticulated foam so that the centre of the assembly is also under compression. Such a compression spreading layer may conveniently be provided by a sheet of filter paper. Other suitable materials may be employed. They should preferably be flexible and porous. Preferably, such a compression spreading material also serves as a wick to draw culture medium from the absorbent support and to supply it to the membrane filter. It should not obstruct expansion of the absorbent support to match expansion of the membrane filter. It may be chosen to expand as much as the membrane filter when wetted.
A liquid sample to be filtered can be placed in a sample chamber above the membrane filter and can be drawn through the membrane filter by suitable means such as a vacuum pump or syringe. The filtered liquid will be withdrawn through an outlet from the filter holder. Preferably, the culture medium is supplied to the absorbent support for the membrane filter through this same outlet. To facilitate this, the apparatus may be inverted at this stage. Preferably, the culture medium is initially contained in a sealed container in which it can be maintained in a sterile condition and the container of culture medium is connected to the outlet of the filter holder prior to the seal being broken to release the culture medium on to the absorbent support.
The invention includes apparatus for use in filtering and culturing micro-organisms comprising a filter holder defining a flow-path for fluid to be filtered, a filter member in said flow-path comprising a membrane filter supported on an absorbent support, and means compressing said absorbent support against the membrane filter.
Preferably, the filter holder may comprise telescopically interfitting first and second sections, said first section having a floor containing an outlet for filtered fluid and a peripheral wall, said membrane filter and said absorbent support therefore being received in said first section on said floor with said membrane filter further away from said floor, and said second section of the filter holder being received in said first section and compressing said membrane filter and said absorbent support against said floor.
The outlet in the floor of the first section of the filter holder may be bridged by a porous support surface underlying the absorbent support of the membrane filter.
Suitably, the outlet in the floor of the first section of the filter holder is adapted for connection to a syringe by a standard syringe fitting.
The apparatus further includes an assay kit comprising apparatus as described above together with a container of sterile liquid culture medium for introduction on to the absorbent support.
Preferably, said container of culture medium is adapted to mate with the outlet of the first section of the filter holder to allow introduction of the culture medium therethrough on to the absorbent support.
Preferably, means are provided at the outlet of the first section of the filter holder for co-operating with the seal of the container of culture medium to break said seal and release the culture medium after a connection has been established between the container of culture medium and the filter holder.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be further described and illustrated with reference to the accompanying drawings in which:
FIG. 1 is a schematic longitudinal section through apparatus according to the invention;
FIG. 2 is a view similar to FIG. 1 of the apparatus in use during the filtration of a sample;
FIG. 3 is a similar view of the apparatus during the introduction of culture medium on to the absorbent support therein;
FIG. 4 shows a second embodiment according to the invention in a perspective view with body and lid portions of the apparatus separated; and
FIG. 5 is a similar view but with both the lid and the body portion cut through on a diameter.
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, a typical apparatus according to the invention comprises a filter holder 10 having a first section 12 and second section 14 interfitting therewith. Both are preferably of circular cross-section transverse to the plane of the drawing. The first section 12 is in the form of a tray having in its base a centrally located outlet 16 and having an upstanding peripheral wall 22 within which is received the cylindrical second section 14 sealed thereto by an O-ring seal 18. A lid 20 is provided for the second section 14.
Within the filter holder there is a positioned a first layer of support material such as plastics scrim 24. Alternatively, the neck of the outlet 16 may be bridged by support material located in the outlet 16 such as a porous plastics plug or spider. Above the support scrim 24 is a pad of reticulated absorbent foam 26 which acts as a support for the membrane filter described hereafter. Above the reticulated foam 26 is a layer of filter paper 28 and above that is a membrane filter 30 itself. The assembly of the reticulated foam 26, filter paper wick 28 and membrane filter 30 is compressed by the bottom edge of the second section 14 of the filter holder 10. The reticulated foam pad may for instance have a 1 cm uncompressed thickness and at the edge of the assembly may be compressed down to say 3 mm. The compression is spread across the centre of the reticulated foam pad principally by the membrane filter but also by the filter paper layer 28 so that in the centre the compression would typically be somewhat less than at the edge, e.g. to 5 mm. The amount of compression applied will generally not be critical. Provided there is some compression, then if there is expansion of the membrane filter during use, the foam pad 26 can expand to accommodate it and maintain contact between the filter paper 28 and the membrane filter 30.
For completeness, FIG. 1 also illustrates the presence of a container 32 in the form of a bulb of liquid culture medium 34 attached by a suitable connector schematically shown at 36 to the outlet 16. In use however, the bulb 32 would not normally be attached to the filter holder 10 at this stage. In place of a flexible bulb containing the culture medium, one might suitable employ a sealed ampoule or closed syringe. Preferably however, whatever form of container is employed will be sealed by a seal 38 which is frangible after the container has been connected to the outlet 16 in a sealing manner. Where the container 32 is a flexible bulb, the seal may be adapted to be burst simply by applying external pressure to the bulb. Alternatively, the connection between the outlet 16 and the connector 36 may be designed such that as the connection is fully made, mechanical means perforates the seal 38. To this end, one could for instance provide a bayonet type lock between the container 32 and the outlet 16 such that after the two have been brought into engagement, the container 32 could be rotated to a position in which it is allowed to be pushed toward the filter holder 10 causing the seal 38 to be ruptured against a pin or other perforating member located in the connector.
The use of the apparatus of FIG. 1 is illustrated in FIGS. 2 and 3. In a first phase, a sample of liquid 40 is introduced into the filter holder 10 and the lid 20 is applied to prevent contamination from the air. Using a syringe 42, the liquid sample is sucked through the filter assembly 26, 28, 30 depositing micro-organisms from the liquid sample on to the upper surface of the membrane filter 30. The apparatus is then inverted as shown in FIG. 3 and the container 32 of culture medium is put into position and its seal 38 is ruptured to release the culture medium 34 on to the absorbent foam 26 from where it is supplied by a wicking action by the paper layer 28 to the membrane filter 30.
The apparatus may then be incubated at a suitable temperature to produce micro-organism growth.
The apparatus described is of simple construction and lends itself to use in the field. For instance, a sample of water taken from a river, reservoir, storage tank or other such source may be placed directly into the filter holder 10 and filtered at the time of sampling. The culture medium may be applied immediately and the culturing process may be initiated. It may take several hours for the sample to be returned to the laboratory at which further work on the sample takes place but the transport time is not wasted. Rather it is used for the culturing of the organisms.
The alternative embodiment shown (with some features omitted for clarity) in FIGS. 4 and 5 is similar in functionality, although different in form. It comprises a filter holder 100 having a lid portion 114 and a body portion 112. Body portion 112 is a plastics integral molding having a circular base plate So from which rises a generally circular wall 52 defining a well. A generally circular flange 54 extends radially outward from the top of the well and carries a cylindrical wall 56 upstanding therefrom. A radially inward portion of the upper surface of the flange 54 forms a ledge 58 for receiving the edge of a filter assembly (not shown) and walls 60 upstanding from the base plate 50 provide support for more central portions of the filter assembly but leave a central channel 61 between their ends 63. The upper surfaces of walls 60 and the lege 58 of flange 54 define a floor on which the filter assembly is received.
Bayonet fitting lugs 62 project radially outward at intervals from the edge of the flange 54.
The lid portion 114 is an integral plastics molding comprising a circular top plate 64 from which depends a cylindrical wall 66 terminating in a radially extending circular flange 68 which bears a further cylindrical wall 70. Within the cylindrical wall 66 is a smaller diameter cylindrical wall 72 spaced therefrom by an annular gap 74 adapted to receive wall 56 of the body portion 112. Lugs for co-operating with bayonet lugs 62 are provided on the interior of wall 70. A through aperture 76 pierces both walls 66 and 72. A depending shield wall 78 is provided on the underside of flange 68, approximately opposite aperture 76.
A circular cross-section bore 80 pierces through wall 52 of the body portion 112 below and parallel to the flange 54 and a similar bore 82 is provided directly opposite.
In use, a filter assembly comprising the scrim 24, reticulated foam 26, filter paper 28 and membrane filter 30 described in connection with FIGS. 1 to 3 is placed on the ledge 58 within the wall 56 after a cylindrical vial containing culture medium is placed in the channel 61.
When the lid position 114 is fitted, the bottom of wall 72 presses on the edge of the filter assembly as described in connection with FIGS. 1 to 3.
The bayonet lugs 62 secure the lid portion to the body portion but allow some twisting movement of one relative to the other whereby aperture 76 may be brought into and out of alignment with a similar aperture 77 in wall 56 and to bring shield wall 78 into and out of a blocking position in relation to bore 82.
Lastly, a chisel member (not shown) is inserted into bore 80 to abut the vial of culture medium. The chisel may have a cylindrical body portion and a pointed end abutting the vial. The sharpened end may be of any desired shape. The cylindrical portion may be a push fit in the bore 80 or may be a threaded engagement with the bore.
A sample to be investigated is introduced via apertures 76, 77, e.g. from a syringe and is passed through the filter assembly to exit via bore 82. Thereafter, the lid and body portions are twisted to close aperture 76 and to bring wall 78 into a blocking position closing bore 82. The chisel is then pressed home (e.g. by turning it if it is threaded) to break the culture medium vial. The culture medium impregnates the foam of the filter assembly and culturing of any trapped micro-organisms commences. The apparatus may be inverted during culturing. After culturing, one may observe micro-organisms through the lid portion and, if desired, the apparatus may be disassembled and the cultured micro-organisms may be investigated further.
The ability to close off the inlet and outlet bores 76, 77 and 82 by rotation of the lid provides a convenient way to exclude contamination during culturing incubation whilst permitting some air access. Also, the apparatus is adapted to be prepared well in advance and to be packed fully assembled in a sterile manner for storage prior to use.
The use of the apparatus may be illustrated by the following examples:
EXAMPLE 1
100 ml of water spiked with E.coli was filtered through the unit described above in relation to FIGS. 1 to 3. A number of such units were prepared in this way. Each unit was inverted and at various volumes and strengths of nutrient broth were allowed to soak into the foam base of each unit. Units were incubated at 37° C. overnight and micro-organism counts as follows were obtained:
______________________________________Nutrient Brothadded Replicate 1 Replicate 2______________________________________5ml × 2X 24 257m1 × 2X 27 273m1 of 2X 27 305ml × 1X 41 25______________________________________
EXAMPLE 2
100 ml of river water diluted in dechlorinated tap water was filter through each of a number of units described above. Various amounts and strengths of membrane lauryl broth (Oxoid) were added to the inverted units to soak into the foam support of each unit. Incubation was conducted overnight at 37° C. and yellow colonies were recorded as presumptive coliforms. The membrane filter from one unit was moved and placed on solidified medium as a control. The micro-organism counts were as follows:
______________________________________Lauryl sulphateadded Replicate 1 Replicate 2______________________________________Agar control 47 374ml × 0.5X 41 714ml 1X 54 604ml of 1.5X 37 51______________________________________
EXAMPLE 3
100 ml volumes of E.coli seeded water samples were filtered through units of the kind described above. Each unit was inverted and 2 ml of 1.3X strength membrane lauryl sulphate broth containing the chromogen BCIG was added to the foam. The broth was made up according to Sartory and Howard but used 39 mg of BCIG/100 ml rather than 20 mg/100 ml. Control membranes were transferred after filtration to MLGA (Sartory et al). Incubation was conducted for 4 hours at 30° C. and 14 hours at 37° C. both green and yellow colonies were counted as follows:
______________________________________Sample Control (agar plate) Foam PadNo. Green Yellow Green Yellow______________________________________1 0 1 0 02 20 0 17 03 34 0 20 04 10 21 28 295 0 0 0 06 0 18 0 107 0 17 0 228 22 0 20 09 17 0 16 010 0 10 0 17______________________________________
In summary it can be concluded that there is no statistically significant difference between the number of organisms recovered on the agar plate or foam pad system. Thus proving that the foam pad system is comparable for agar plates even when more complex growth media i.e. inclusion of chromogens are used in the system.
Whilst the invention has been described with reference to the specific embodiment illustrated, many variations and modifications thereof are possible within the scope of the invention. | A method and apparatus for filtering microorganisms from a sample and culturing the microorganisms employs a membrane filter (3) in a filter holder (10) in which holder the membrane filter is supported on an absorbent support (26) which is maintained in an expansible compressed state against the membrane filter so that any expansion of the membrane filter when wetted by a sample does not cause bubbling of the membrane filter away from its support entrapping air bubbles and so preventing supply of nutrient from culture medium supplied to the support from reaching the microorganisms on the membrane filter. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to neutron absorbing alloys, and in particular to an iron base alloy and an article of manufacture made from said alloy that can be processed to provide a unique combination of mechanical properties, corrosion resistance, and thermal neutron absorbability.
2. Description of the Related Art
Boron-containing stainless steels are used by the nuclear power industry for the storage, transportation, and control of radioactive materials. The suitability of this type of material in those applications is related to the increased thermal neutron absorption capability provided by the addition of boron, specifically the B 10 isotope, to the base material. An example of such a material is a modified Type 304 stainless steel sold under the registered trademark MICRO-MELT® NEUTROSORB PLUS® and described and claimed in U.S. Pat. Nos. 4,891,080 and 5,017,437. Boron may be present in that material as natural boron, which contains approximately 18.3 weight percent B 10 isotope (the balance being the B 11 isotope), enriched boron, or a combination thereof. Applications for the known material in the nuclear power industry include wet spent fuel storage racks, baskets for spent fuel dry storage transportation casks, reactor control rods, burnable poison, and neutron shielding plates. The rising costs associated with natural gas and petroleum as well as the environmental issues surrounding the use of coal in the generation of electricity have sparked a renewed interest world-wide in the use of nuclear power to augment the use of fossil fuels to generate electric power. The waste products generated by current and future nuclear power plants will need to be stored either on-site or at regional or national repositories. The benefit provided by boron to the nuclear power industry is related to its effect of increasing a material's thermal neutron absorption cross-section. Higher boron loads or the use of alternative neutron absorbers by themselves or when coupled with boron could provide a technical and marketing advantage for many articles used in these applications.
Boron is the traditional standard bearer for neutron absorption in containment materials. Although boron has only the sixth largest thermal neutron cross-section of all naturally occurring materials, its low atomic mass makes it the second most effective alloying addition on a weight percent basis. All of the neutron absorption capabilities of boron are derived from the B 10 isotope. However, B 10 enriched boron is generally cost prohibitive for use in commercial alloy systems, and as such, natural boron is normally used. Boron has little or no solubility in stainless steel or nickel-based alloys. Instead, it generally forms borides that are enriched with Cr, Mo and Fe. For example, in the MICRO-MELT NEUTROSORB PLUS alloy an M 2 B phase forms with a composition of about 46% Cr, 40% Fe, 3.5% Mn, 1.0% Ni and 9.5% B.
Boron additions to austenitic stainless steels result in improved neutron absorption characteristics, increased hardness, yield strength and tensile strength, but reduced tensile ductility, impact toughness, and corrosion resistance. The reduced corrosion resistance results from a depletion of matrix Cr as a result of the formation of the Cr-rich M 2 B phase. Typically, boron-containing stainless steels have not been used as structural components in the United States because of the toughness and ductility limitations that are usually associated with the use of boron additions in conventionally processed alloys. Through the use of alloy modifications and powder metallurgy processing, MICRO-MELT NEUTROSORB PLUS alloys minimize the reductions in corrosion resistance, ductility, and impact toughness that are associated with the addition of boron to conventional Type 304 stainless steel. The MICRO-MELT® NEUTROSORB PLUS® alloys contain up to 2.25% B and are covered by ASTM A887 Grade “A”, while conventionally processed materials are covered by ASTM A887 Grade “B”. Some steel producers will not sell cast and wrought borated stainless steels with B contents higher than about 1.85%. This is related to the fact that there are significant processing issues with conventional cast and wrought borated stainless steels containing more than this amount of B. Such processing issues include cracking and tearing of the alloy material when it is mechanically hot worked. The powder metallurgy (P/M) borated stainless steels sold under the MICRO-MELT NEUTROSORB PLUS and MICRO-MELT NEUTROSORB trademarks offer the opportunity to provide customers with a higher neutron absorption capability as a result of the reduced segregation associated with P/M produced material. However, there is a limit of nominally 3.5% boron that can be added to NEUTROSORB PLUS alloys and still have a processable alloy (i.e., one that can be hot worked into plate or bar). In addition, if the amount of B can be reduced through the use of a second and stronger neutron attenuating material, then a higher B equivalency (B Eq ) can be obtained in P/M processed alloys.
The NEUTROSORB PLUS alloys contain enriched B 10 or enriched B 10 plus natural B to obtain B Eq values higher than what would be attainable by using only natural B. Enriched B 10 is, however, very expensive (on the order of $1600/lb), which makes using it not cost effective in many applications. Use of a non-enriched element that has a higher B Eq than natural B and that is significantly less expensive than enriched B 10 would be preferred.
SUMMARY OF THE INVENTION
The disadvantages associated with the known corrosion resistant, neutron absorbing alloys are solved to a large degree by the material in accordance with the present invention. In accordance with a first aspect of the present invention there is provided a corrosion-resistant, austenitic alloy powder having the following composition in weight percent.
C 0.08 max. Mn up to 3 Si up to 2 P 0.05 max. S 0.03 max. Cr 17-27 Ni 11-20 Mo + (W/1.92) up to 5.2 B Eq 0.78-13.0 O 0.1 max. N up to 0.2 Y less than 0.005
The balance of the alloy composition is iron and usual impurities. B Eq is defined as % B+4.35×(% Gd) and the alloy contains at least about 0.25% B and at least about 0.05% Gd.
In accordance with another aspect of the present invention, there is provided an article of manufacture made from consolidated alloy powder having the weight percent composition set forth above. The powder metallurgy article according to this invention also includes a plurality of boride and gadolinide particles dispersed within a matrix. The boride and gadolinide particles are predominantly M 2 B, M 3 B 2 , M 5 X, and M 3 X in form where X is gadolinium or a combination of gadolinium and boron and M is selected from the group consisting of silicon, chromium, nickel, molybdenum, iron, and combinations thereof.
An alloy and articles made therefrom, in accordance with the present invention provide a novel combination of strength, toughness, corrosion resistance, and processability. Here and throughout this specification the terms “processability” and “processable” relate to the ability of an alloy or article to be worked thermomechanically without sustaining substantial cracking and/or tearing. The degree of cracking or tearing can be measured with respect to crack volume and crack depth of as hot-worked material. Processability can be assessed based on the ductility and toughness of the alloy material as determined by standard testing procedures.
Here and throughout this specification the following definitions apply. The term “percent” and the symbol “%” designate percent by mass (percent by weight), unless otherwise indicated. The term “boron” or the symbol “B” when used without further qualification means natural boron. The term “powder”, “alloy powder”, or “metal powder” means an aggregate of discrete alloy or metal particles that are typically in the size range of 1 to 1000 μm.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing summary and the following detailed description will be better understood when read with reference to the drawings, wherein:
FIG. 1 shows comparative graphs of yield strength as a function of boron equivalent, (% B Eq );
FIG. 2 shows comparative graphs of ultimate tensile strength as a function of % B Eq ;
FIG. 3 shows comparative graphs of percent elongation as a function of % B Eq ;
FIG. 4 shows comparative graphs of percent reduction in area as a function of % B Eq ;
FIG. 5 shows comparative graphs of Charpy V-notch toughness as a function of % B Eq ;
FIG. 6 shows comparative graphs of bend angle as a function of % B Eq ;
FIG. 7 shows comparative graphs of Huey corrosion rate as a function of % B Eq
FIG. 8 shows comparative graphs of bend angle as a function of the mean area fraction of boride and gadolinide particles;
FIG. 9 shows comparative graphs of yield strength as a function of boron content in wt. % (% B);
FIG. 10 shows comparative graphs of ultimate tensile strength as a function of % B;
FIG. 11 shows comparative graphs of percent elongation as a function of % B;
FIG. 12 shows comparative graphs of percent reduction in area as a function of % B;
FIG. 13 shows comparative graphs of Charpy V-notch toughness as a function of % B;
FIG. 14 shows comparative plots of Charpy V-Notch toughness as a function of ultimate tensile strength;
FIG. 15 shows comparative graphs of Huey corrosion rate as a function of time;
FIGS. 16A and 16B are photomicrographs of a longitudinal section showing two different regions of sample material from Heat 046 at a magnification of 500×;
FIG. 17 is a photomicrograph of a longitudinal section of sample material from Heat 881 at a magnification of 500×;
FIG. 18 is a photomicrograph of a longitudinal section of sample material from Heat 047 at a magnification of 500×;
FIG. 19 is a photomicrograph of a longitudinal section of sample material from Heat 866 at a magnification of 500×;
FIGS. 20A and 20B are photomicrographs of a longitudinal section showing two different regions of sample material from Heat 048 at a magnification of 500×;
FIG. 21 is a photomicrograph of a longitudinal section of sample material from Heat 869 at a magnification of 500×;
FIGS. 22A and 22B are photomicrographs of a longitudinal section showing two different regions of sample material from Heat 049 at a magnification of 500×;
FIG. 23 is a photomicrograph of a longitudinal section of sample material from Heat 870 at a magnification of 500×;
FIG. 24 is a photomicrograph of a longitudinal section of sample material from Heat 050 at a magnification of 500×; and
FIG. 25 is a photomicrograph of a longitudinal section of sample material from Heat 868 at a magnification of 500×.
DETAILED DESCRIPTION OF THE INVENTION
An alloy and articles made therefrom in accordance with the present invention include the following constituents.
The alloy contains not more than about 0.08% and preferably not more than about 0.05% carbon. In this alloy system carbon, which is an austenite stabilizer, is considered to be a residual element. However, with the chromium content of this material, carbon is restricted to not more than about 0.08% and preferably to not more than about 0.05% to avoid the formation of chromium carbides which could adversely affect the corrosion resistance of the material because of sensitization. Sensitization is the precipitation of chromium carbides in an alloy, particularly at the grain boundaries after exposure to certain elevated temperatures. The alloy grains are thus depleted of chromium in their boundary regions creating areas that are susceptible to corrosive attack.
The alloy according to this invention contains up to about 3% manganese. Manganese like nickel is an austenite stabilizer. This level of manganese permits the use of a reduced amount of nickel than would otherwise be required. Nickel is a more expensive alloying element than manganese. Preferably, the alloy contains at least about 1% manganese. Manganese also increases the solubility of nitrogen in this alloy which beneficially affects the corrosion resistance provided by the alloy.
The alloy also contains up to about 2% silicon. Silicon is typically present in the austenitic stainless steel at a level of about 0.5%. At this level silicon is an effective deoxidizer and thus obviates the need to use aluminum and/or yttrium to deoxidize the molten alloy. Also, because the alloy contains gadolinium as a supplemental neutron absorber, there is some partitioning of silicon to the gadolinide phase.
The alloy also contains about 17-27% chromium. Chromium is a ferrite stabilizer and is necessary in the alloy primarily to benefit the corrosion resistance of the alloy. Chromium also combines with boron to form borides (particularly M 2 B borides) which are needed to absorb thermal neutrons. At least about 17% chromium is present to provide corrosion resistance beyond what is currently provided by the known alloys. On the other hand more than about 27% chromium will result in the formation of excessive ferrite (i.e., more than about 10% by volume), particularly in any subsequent welds that might be produced by end users of this product.
The alloy contains at least about 11% nickel, and preferably at least about 12% nickel, in order to avoid the formation of ferrite which adversely affects the corrosion resistance of the alloy. Nickel is an austenite stabilizer and is present to offset the ferrite stabilizing effects of chromium and molybdenum. Because of the presence of manganese, the alloy contains less nickel than would otherwise be needed to provide the same degree of phase stability. In addition to offsetting the ferrite stabilizing effects of chromium and molybdenum, nickel partitions to the gadolinide phase that forms. The partitioning of nickel to the gadolinide phase results in a lower iron content in that phase. The lower iron, higher nickel gadolinide phase benefits the hot-workability of the alloy. Too much nickel increases the cost of the alloy without providing a significant benefit in properties. Therefore, the alloy contains not more than about 20% nickel, and preferably not more than about 16% nickel.
The alloy may contain up to about 5.2% molybdenum. Molybdenum like chromium is a ferrite stabilizer and when present it contributes to the corrosion resistance of the alloy. The benefit to corrosion resistance is obtained when the alloy contains at least about 2.8%, better yet at least about 3.0%, and preferably at least about 3.5% molybdenum. When the additional corrosion resistance provided by the addition of molybdenum is not needed, the alloy may contain a residual amount of molybdenum, preferably, not more than about 0.5% molybdenum.
Molybdenum also partitions to the boride phases that form in articles according to this invention. In the chromium-rich M 2 B boride phase, there is approximately 2.0% Mo. However, the M 3 B 2 boride phase is believed to contain almost 60% Mo. The M 3 B 2 phase that forms is more highly enriched in boron compared to the chromium-rich M 2 B phase, and consequently results in the formation of less of the neutron absorbing second phase. This is important because as the area fraction of the neutron absorbing second phase increases, mechanical properties are adversely affected. Thus, by controlling the amount of these second phase particles, properties can be modified. In particular, tensile and yield strength increases with higher amounts of the second phase boride particles. However, ductility, toughness, NTS/UTS ratio (notch tensile strength to ultimate tensile strength ratio), and bend radius decrease with increasing amounts of the second phase boride particles.
Tungsten is an element that behaves in a manner similar to molybdenum in this alloy. However, because of the differences in atomic weight between molybdenum and tungsten, it takes nearly twice as much tungsten on a weight percent basis to obtain the same effect as a given amount of molybdenum. It is envisioned that tungsten can substitute for all or part of the molybdenum in this alloy system. To ensure the appropriate levels of molybdenum and tungsten are present, a molybdenum equivalency factor, Mo Eq , has been derived. The factor Mo Eq is defined as % Mo+% W/1.92. It is used to determine the proper level of tungsten substitution for molybdenum to obtain an equivalent amount of molybdenum plus tungsten relative to 3.0-5.1% molybdenum.
The alloy may contain up to 0.2% nitrogen and preferably contains up to about 0.1% nitrogen. Nitrogen is a strong austenite stabilizer. Although nitrogen reduces the toughness and ductility properties of borated stainless steel, the inclusion of nitrogen in the alloy allows for the use of nitrogen gas atomization of the metal powder to reduce the cost of producing the alloy powder relative to argon gas atomization. The use of nitrogen gas for atomization enhances the corrosion resistance. Nitrogen gas atomization also enhances the weldability of the alloy because an article made from nitrogen atomized alloy powder does not develop micro-porosity in the weld zone as does an article made from argon-atomized material. Therefore, when atomized with nitrogen gas the alloy powder contains more than 300 ppm nitrogen, for example, at least about 0.05%.
The alloy powder of this invention preferably contains at least about 0.25% boron. Boron benefits the thermal neutron absorption capability of the product. This is accomplished through the formation of the second phase boride particles such as M 2 B and M 3 B 2 . Since those particles contain chromium and molybdenum, it is important to maintain the required matrix level of those elements to ensure that the corrosion resistance and phase stability are not adversely affected. At least about 0.25% boron is needed to effectively co-nucleate with the gadolinide phase that forms in the material, such co-nucleation benefits the processability of the alloy. Too much boron adversely affects the toughness, ductility, and processability of the alloy. Therefore, boron is restricted to not more than about 2.5%, better yet to not more than about 2.0%, and preferably to not more than about 1.0% in this material. Good strength and acceptable toughness and ductility are obtained when the alloy contains more than 2% boron. A good combination of strength, toughness, and ductility are obtained when the alloy contains 2% boron or less. The best toughness and ductility are obtained when the alloy contains not more than about 1% boron.
The alloy further contains at least about 0.05% and preferably at least about 0.12% gadolinium. Gadolinium is a neutron absorber like boron. However, unlike boron, gadolinium forms a gadolinide phase that is rich in nickel and iron. Because the gadolinide phase ties up nickel, it is important to balance out this partitioning effect to ensure proper phase stability. Gadolinium is 4.35 times more potent as a thermal neutron absorber compared to naturally occurring boron. Therefore, gadolinium can be used to cost effectively reduce the overall amount of thermal neutron absorbing second phase boride particles to create improved property performance. Consequently, the volume fraction of the second phase boride particles in this alloy can be reduced relative to the known alloy while the material provides neutron absorption capability that is at least as good as that provided by the known boron-only alloy. Nevertheless, it is important that boron be present in conjunction with gadolinium because some of the boron in the alloy partitions to the gadolinide phase and the gadolinide phase co-nucleates with the boride phases during solidification. This is significant because straight gadolinium-bearing alloys have limited hot-workability because of the formation of a low melting phase. The combination of gadolinium, boron, and nickel as set forth above, together with powder metallurgy processing, benefits the hot workability of the material compared to the known gadolinium-bearing materials. Too much gadolinium adversely affects the hot workability and processability of the alloy. The alloy powder of this invention may contain up to about 2.6% gadolinium.
The beneficial contribution of both boron and gadolinium relative to neutron absorption capability can be quantified by reference to a boron equivalency factor, B Eq . The factor B Eq is a means to express the boron level that is equivalent to the combination of boron and gadolinium, in terms of neutron absorption. According to this invention, B Eq is described as % B+(4.35×% Gd) because Gd is 4.35 times more potent as a thermal neutron absorber compared to natural boron. The balance of the alloy composition is iron and the usual impurities found in commercial grades of iron-base neutron absorbing alloys. Phosphorus is an impurity and is preferably restricted to a residual level of about 0.05% max. in order to avoid an adverse effect on the workability of the alloy resulting from hot shortness. Sulfur, like phosphorus, is an impurity and is preferably restricted to a residual level of about 0.03% max. in order to avoid an adverse effect on the workability of the alloy resulting from hot shortness. Deoxidizing additions such as aluminum and yttrium are not intentionally present in this alloy, but may be present as inevitable impurities. Accordingly, the alloy powder contains less than 0.01% aluminum and less than 0.005% yttrium. Oxygen is inevitably present in this alloy, and the alloy may contain up to about 0.1% oxygen depending on how fine the powder is. It is expected that the alloy powder will contain at least about 100 ppm oxygen unless special techniques are employed.
Although a broad range of alloy compositions is described above, it is contemplated that preferred ranges of alloys will be realized depending on the property requirements for particular applications of the articles according to this invention. For example, subranges of the various element ranges described above can be selected to optimize particular properties such as corrosion resistance, neutron absorption, strength, toughness, and combinations thereof, to mention a few.
An article in accordance with the present invention is preferably formed by a powder metallurgy process. The preferred powder metallurgy process is as follows. The alloy is first melted under an oxygen-free atmosphere, e.g., vacuum induction melting (VIM), and atomized by means of an inert atomizing fluid such as argon gas or nitrogen gas. The particle size of the prealloyed powder is not critical, but it is desirable to remove excessively large particles. Sifting the prealloyed powder through a 40 mesh screen for that purpose gives good results. Segregation of the powder by particle size can be advantageously minimized by blending the powder. Thus, before the powder material is placed in a container, it is preferably blended to obtain a uniform particle size distribution.
The alloy powder is filled into one or more metal canisters prior to consolidation. When the canister is made from an austenitic stainless steel, such as AISI type 304 or 316 stainless steel, the alloy powder and the canister are preferably baked to remove moisture prior to the powder being loaded into the canister. The baking temperature in air is preferably less than 400° F. to avoid oxidation. A baking temperature of 250° F. has provided good results. The dried powder is loaded into the canister which must be clean and essentially free of oxides. A canister made of a low carbon, mild steel can also be used. In such event, it is not necessary to bake the alloy powder or the canister prior to filling the canister.
When the canister is filled with the powder it is closed and then preferably evacuated to remove air and any absorbed moisture. To this end the canister is preferably evacuated to less than 100 microns Hg. The canister can be heated during the evacuation process to facilitate the removal of moisture. When the air and water vapor levels inside the canister are satisfactory, evacuation is stopped and the canister is sealed and then compacted.
Hot isostatic pressing (HIP'ng) is the preferred method for compacting the metal powder. As is well known, the temperature, pressure, and the duration for which the material is held at the selected temperature and pressure depend on the alloy powder and the canister size and shape, all of which are readily determined. The temperature to be used must be below the incipient melting temperature of the alloy. The HIP'ng temperature is kept low, preferably about 2000°-2100° F. to limit growth of the boride/gadolinide particles. The HIP cycle is preferably conducted at a pressure of about 15 ksi for a time sufficient to obtain a substantially fully dense compact. The time required at temperature and pressure depends on the section size of the canister, i.e., more time is needed for larger canister section thickness.
Although preparation of an alloy compact used in the present invention has been described with reference to a conventional powder metallurgy technique, it is contemplated that it can be prepared by other methods. For example, the simultaneous consolidation and reduction of metal powder disclosed in U.S. Pat. No. 4,693,863 could be utilized. Rapid solidification casting techniques are also applicable to the present invention. It is important that the method of preparation selected provide rapid cooling of the alloy from the molten state and that any intermediate consolidation steps be limited with respect to temperature, in order to limit the growth of the boride particles.
The compacted alloy powder can be hot and/or cold worked to the desired article form. More particularly, the alloy is mechanically hot worked from a starting temperature in the range of 2050°-2125° F., by pressing, hammering, rotary forging, or flat rolling. A preferred method of hot working the material includes hot forging the alloy powder compact from a starting temperature of about 2050°-2125° F. followed by hot rolling from a starting temperature of about 2050°-2125° F. to provide a flat form such as strip or plate. The flat form can be cold rolled or ground to finish size as required. The final form of the article is preferably annealed at about 1900°-1950° F. for 30 minutes and rapidly quenched to room temperature preferably in water.
WORKING EXAMPLES
Twenty-six (26) nominal 140-300 lb heats were vacuum induction melted and atomized. Twenty-four of the heats were atomized with argon gas and the other two heats (878 and 879) were atomized with nitrogen gas. The weight percent compositions of the heats are set forth in Tables IA and IB below. Table IA shows the compositions of the alloy according to the present invention and Table IB shows the compositions of comparative alloys. The balance of each heat was iron and usual impurities.
The atomized alloy powder from each heat was screened to −40 mesh (420 micron and finer) and blended. A portion of the blended powder of Heat 105 was further screened to −140 mesh and −270 mesh to provided three separate batches, hereinafter designated Heats 105-1, 105-2, and 105-3, respectively). The alloy powder from each heat and from the three batches of Heat 105 was vibration filled into two (2) 1¾ inches×6 inches×26 inches canisters formed from 0.125 inch thick, low carbon steel. The canisters were degassed at 250° F., evacuated to a pressure of less than 20 microns Hg, welded shut, and then hot isostatically pressed (HIP'd) at 15 ksi and 2050° F. for 4 to 6 hours at temperature and pressure to substantially full density. One HIP'd canister per heat was hot-rolled to ¾-inch thick plate. In order to facilitate handling each canister was sectioned prior to hot rolling. All material was hot-rolled from a starting temperature of 2050° F. using ⅛-inch reductions per pass and 2 passes per heating cycle. The intermediate material was reheated at 2050° F. for 20-30 minutes after each rolling pass. Upon completion of the final roll pass, the ¾-inch plate sections were straightened and then annealed for 1 hour at 1950° F. followed by water quenching to room temperature. The heats containing boron and gadolinium according to the present invention were successfully hot rolled as evidenced by an absence of tears or cracks in the as-processed plate. Accordingly, it was verified that the alloys according to the present invention demonstrated processability despite the presence of boron and gadolinium in the alloy material. Heat 876 having a B Eq higher than the alloy of the present invention and a boron content very near the upper limit of this alloy was not processable as evidenced by significant hot tearing during the hot-rolling step.
TABLE IA
Ele-
Composition (%)
ment
715
716
757
758
760
761
762
873
874
875
877
878
879
880
105 1
C
0.021
0.044
0.032
0.036
0.024
0.039
0.040
0.022
0.040
0.038
0.015
0.005
0.015
0.008
0.022
Mn
1.99
1.76
2.26
2.12
2.12
2.38
2.39
2.22
2.55
2.53
2.13
2.03
2.22
2.00
2.12
Si
0.53
0.46
0.38
0.44
0.44
0.38
0.36
0.50
0.44
0.43
0.59
0.55
0.49
0.56
0.52
P
0.010
0.006
0.004
0.005
0.004
0.006
0.004
<0.005
0.008
0.009
<0.005
<0.005
<0.005
<0.005
0.003
S
0.002
0.002
<0.001
<0.001
0.001
0.001
0.001
0.002
0.004
0.002
0.003
<0.001
0.005
0.001
0.002
Cr
22.12
24.38
22.70
21.20
21.18
24.39
24.10
20.07
23.51
23.51
18.30
17.82
20.00
17.95
20.07
Ni
13.50
13.68
12.92
13.64
13.64
12.29
12.65
12.91
11.62
11.92
14.03
13.17
12.83
13.19
13.18
Mo
4.04
0.01
4.54
3.98
3.98
5.24
5.19
3.85
5.11
5.17
3.26
2.87
3.86
2.87
3.70
Cu
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
Co
0.01
0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
Ti
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
N
0.0014
0.0018
0.0014
0.0017
0.0013
0.0017
0.0012
0.002
0.002
0.002
0.002
0.162
0.075
0.002
0.002
B
1.14
3.04
1.52
1.82
1.14
2.01
2.03
1.04
1.98
2.02
0.69
0.23
0.97
0.28
1.02
O
0.0212
0.0199
0.0232
0.0232
0.0204
0.0201
0.0177
0.015
0.013
0.024
0.016
0.016
0.038
0.012
0.024
Gd
0.06
0.14
0.18
0.26
0.22
0.56
1.20
1.68
1.80
2.52
2.56
0.13
1.45
0.17
1.68
Al
0.002
0.004
0.002
0.003
0.006
0.005
0.006
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
Y
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
B Eq
1.40
3.65
2.30
2.95
2.1
4.45
7.25
8.35
9.81
12.98
11.83
0.80
7.28
1.02
8.33
N.A.: element not analyzed
1 Heat 105 is blend of the powders from two argon atomized heats (871 and 872), the wt. % compositions of which are set forth below.
C
Mn
Si
P
S
Cr
Ni
Mo
Cu
Co
Ti
N
B
O
Gd
Al
Y
B Eq
Ht. 871
0.017
2.14
0.49
<0.005
0.002
20.08
13.25
3.85
<0.01
<0.01
<0.01
0.003
1.00
0.022
1.57
N.A.
N.A.
7.83
Ht. 872
0.018
2.22
0.49
<0.005
0.002
20.02
13.05
3.72
<0.01
<0.01
<0.01
0.002
1.04
0.010
1.66
N.A.
N.A.
8.26
TABLE IB
Composition (%)
Element
708
709
710
711
712
713
754
755
756
876
C
0.037
0.040
0.040
0.046
0.025
0.041
0.021
0.038
0.036
0.042
Mn
1.68
1.71
1.73
1.75
1.71
1.76
2.09
2.44
2.43
2.66
Si
0.54
0.52
0.48
0.48
0.52
0.48
0.48
0.39
0.40
0.41
P
<0.005
0.005
0.006
0.006
0.011
0.011
0.003
0.005
0.005
0.011
S
0.001
0.001
0.001
0.002
0.002
0.001
0.001
0.001
0.002
0.001
Cr
19.48
22.05
24.36
26.27
24.01
24.12
21.28
24.71
24.67
25.33
Ni
13.52
13.58
13.66
13.68
13.44
13.53
13.48
11.93
12.00
11.32
Mo
<0.01
<0.01
<0.01
<0.01
4.42
3.89
4.00
5.28
5.34
5.74
Cu
<0.01
<0.01
0.01
0.01
<0.01
0.01
<0.01
<0.01
<0.01
<0.01
Co
0.01
0.01
0.01
0.01
0.01
0.02
<0.01
<0.01
<0.01
<0.01
Ti
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
N.A.
<0.01
N
<0.0010
<0.0010
<0.0010
<0.0010
0.0011
0.0013
<0.0010
0.0012
0.0012
0.002
B
2.06
2.60
3.03
3.51
1.50
2.98
1.12
1.97
1.97
2.48
O
0.0186
0.0193
0.0174
0.0227
0.0192
0.0209
0.0206
0.0178
0.0181
0.014
Gd
—
—
—
—
—
—
<0.01
<0.01
<0.01
2.52
Al
0.002
0.002
0.002
0.003
0.001
0.002
0.001
0.001
0.001
N.A.
Y
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
N.A.
B Eq
2.06
2.60
3.03
3.51
1.50
2.98
1.12
1.97
1.97
13.44
N.A.: element not analyzed.
Standard size, longitudinal specimens for tensile, Charpy V-notch, bend angle, Huey corrosion testing were prepared from the ¾-inch thick plates of each heat. The results of room temperature mechanical testing including the 0.2% offset yield strength (0.2% YS) and the ultimate tensile strength (UTS) in ksi, the percent elongation (% El.) and the percent reduction in area (% R.A.) are presented in Table HA below for the heats representing the alloy of this invention (Table IA). The results for the comparative heats (Table IB) are presented in Table IIB. Also shown in Tables IIA and IIB are the results of room temperature Charpy V-notch impact testing (CVN) in foot-pounds (ft.-lbs.), the ratio of the notch tensile strength (K t =8.0) to ultimate tensile strength (NTS/UTS), the results of bend testing (Bend Angle) in degrees, and the results of Huey corrosion testing (Con. Rate) in mils per year (mpy).
The bend test is performed as follows. The test specimen, which is a standard Strauss corrosion test coupon (as per ASTM A262, Practice A), is bent through a 1 9/16 inch wide slot using a ⅜ inch diameter mandrel and 1200 psi hydraulic ram. The Huey corrosion testing was performed in accordance with ASTM A262, Practice C.
TABLE IIA
0.2%
%
Bend
Corr.
Heat
YS
UTS
% El.
R.A.
CVN
NTS/UTS
Angle
Rate
715
56.2
113.8
29.3
45.0
32.1
1.13
106.1
25.00
716
80.5
142.9
17.8
9.7
3.9
0.81
43.0
206.50
757
59.9
122.0
23.0
32.0
18.7
1.05
104.0
91.50
758
58.3
123.7
19.5
26.7
14.6
1.04
97.0
134.40
760
56.3
113.2
29.2
42.1
28.1
1.11
106.0
42.80
761
70.0
134.0
13.6
17.3
7.9
1.00
60.0
92.60
762
73.7
134.3
11.1
13.5
5.4
0.89
38.0
230.90
873
52.9
113.0
20.5
22.3
17.7
1.06
105.0
295.1
874
68.3
123.5
5.1
6.3
4.7
0.95
35.3
457.4
875
67.2
121.3
3.8
5.3
3.6
0.84
30.0
750.5
877
47.2
104.9
18.9
19.8
16.1
1.00
107.0
549.7
878
45.6
100.5
46.2
62.5
69.7
1.21
108.0
15.6
879
54.2
113.1
21.7
28.3
23.0
1.11
106.3
129.8
880
40.2
93.9
48.4
64.0
84.9
1.20
109.0
23.0
105-1
51.7
111.7
20.2
20.2
18.1
1.00
107.0
335.4
105-2
53.8
112.5
19.0
19.7
18.2
1.02
107.0
185.8
105-3
52.6
112.2
21.6
22.4
17.7
1.02
106.7
231.4
TABLE IIB
0.2%
%
Bend
Corr.
Heat
YS
UTS
% El.
R.A.
CVN
NTS/UTS
Angle
Rate
708
85.2
116.9
22.4
35.7
19.4
1.03
107.2
209.35
709
68.4
130.3
13.8
13.8
8.7
0.95
80.6
293.50
710
75.0
137.9
7.6
10.2
4.5
0.85
38.6
279.50
711
85.2
150.3
3.5
5.7
1.7
0.59
22.3
365.55
712
59.6
121.4
24.7
36.2
23.2
1.09
105.2
32.25
713
83.5
144.4
5.2
8.0
2.8
0.75
31.4
231.00
754
48.6
111.5
31.7
46.4
33.5
1.07
108.0
57.30
755
68.0
132.3
17.1
20.7
10.7
1.01
63.0
111.10
756
67.2
131.8
15.6
19.2
10.1
0.96
73.0
105.00
876
84.8
133.9
2.2
0.8
Note
0.63
16.0
852.8
Note: Not tested because usable test specimens could not be obtained.
The values presented are the averages of the measured values. For Heats 708 to 716 the mechanical, CVN, and NTS/UTS results are the averages for five (5) tested specimens of each heat. For Heats 754 to 762, 873 to 880, 105-1, 105-2, and 105-3, the mechanical, CVN, and NTS/UTS results are the averages for three (3) tested specimens of each heat. For Heats 708 to 716 and 754 to 762, the bend testing and Huey corrosion testing results are the averages for two (2) specimens of each heat. For the other heats, the bend testing and Huey corrosion testing results are the averages for three (3) specimens of each heat.
Graphical analyses of the test results shown in Tables IIA and IIB as a function of B Eq are presented in FIGS. 1-7 . There is generally good agreement between the variable being plotted and the B Eq content. Both the 0.2% YS and UTS plots ( FIGS. 1 and 2 ) show that the trend line of the heats having B≧2% lies above that of the trend line for the heats with a B≦1% at a comparable B Eq . Plots of tensile ductility, CVN impact toughness, and bend angle as a function of B Eq content ( FIGS. 3-6 ) clearly show the superior ductility, toughness, and fabricability provided by the heats with boron content≦1% at a comparable B Eq content when compared to the heats with a boron content≧2% and the straight B-bearing 304 L heats. The graphs in FIG. 7 for Huey corrosion rate show the superior corrosion resistance provided by the 316 L-based (Mo-containing) heats containing boron and gadolinium when compared to the 304 L-base heats (<0.5% Mo) containing boron, but no positive addition of gadolinium.
The bend angle test results were analyzed as a function of mean area fraction of the boride and gadolinide particles. A graphical analysis is shown in FIG. 8 which clearly indicates a rapid drop-off in the bend angle achieved when the mean particle area fraction is greater than about 22%.
Comparison of Powder Metallurgy Product to Cast-Wrought Product
In order to demonstrate the significant improvement in processability provided by the powder metallurgy product according to this invention, a series of powder metallurgy heats was prepared for comparison with a series of cast and wrought heats of known alloys that contains B and Gd. The weight percent compositions of the test heats are set forth in Table III below.
TABLE III
Heat
Heat
Heat
Heat
Heat
Heat
Heat
Heat
Heat
Heat
Element
046
881
047
866
048
869
049
870
050
868
C
0.007
0.008
0.009
0.006
0.012
0.015
0.013
0.21
0.008
0.011
Mn
0.31
0.39
0.83
0.89
1.14
1.18
1.20
1.22
1.14
1.16
Si
0.20
0.20
0.23
0.24
0.34
0.27
0.38
0.40
0.33
0.34
P
<0.005
<0.005
<0.005
0.006
<0.005
<0.005
<0.005
<0.005
0.005
<0.005
S
<0.001
0.001
<0.001
<0.001
<0.001
<0.001
<0.001
0.001
<0.001
<0.001
Cr
22.12
22.12
18.12
18.16
20.22
20.44
20.66
20.76
20.34
20.52
Ni
18.56
18.25
10.35
10.16
11.62
11.73
11.64
11.64
15.14
15.16
Mo
2.78
2.88
4.13
4.22
0.06
0.11
<0.01
<0.01
4.05
4.13
Cu
<0.01
<0.01
<0.10
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
Co
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
0.01
<0.01
<0.01
Ti
0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
O
0.003
0.010
0.002
0.015
0.001
0.022
<0.001
0.014
<0.001
0.014
Gd
0.42
0.44
0.32
0.27
0.79
0.66
0.46
0.54
0.33
0.26
N
0.001
0.001
0.002
0.002
0.002
0.002
0.002
0.002
0.003
0.003
B
0.39
0.40
0.12
0.26
0.62
0.62
1.10
1.14
0.54
0.58
Al
0.03
—
0.03
—
0.10
—
0.09
—
0.12
—
Y
0.028
—
—
—
—
—
—
—
—
—
Mg
—
—
—
—
0.032
—
0.032
—
0.034
—
B Eq
2.22
2.31
1.51
1.43
4.06
3.49
3.10
3.49
1.98
1.71
Note:
The balance of each heat was iron and usual impurities.
The weight percent compositions of Heats 046 and 047 are similar to Examples 8 and 20, respectively, described in U.S. Pat. No. 5,820,818. The weight percent compositions of Heats 881 and 866 were selected to be similar to Heats 046 and 047, respectively. The weight percent compositions of Heats 048, 049, and 050 are similar to Examples 3, 5, and 16, respectively, described in published Japanese patent application JP 06-1902792. The weight percent compositions of Heats 869, 870, and 868 were selected to be similar to Heats 048, 049, and 050, respectively.
Heats 046, 047, 048, 049, and 050 were vacuum induction melted, cast as 35 lb. ingots, and allowed to solidify. During melting, these heats were deoxidized with aluminum and yttrium in accordance with the descriptions in the respective patent documents. Heats 881, 866, 869, 870, and 868 were vacuum induction melted, nominal 170 pound heats. Each of these heats was atomized with argon gas to form metal powder. The metal powder of each heat was blended and screened to −40 mesh and then filled into two (2) 4½ inch square by 9 inch long canisters formed from 0.125 inch thick, low carbon steel. The filled canisters were sealed, degassed, and then hot isostatically pressed (HIP) at 2050° F. and 15 ksi for 4-6 hours at temperature and pressure to substantially full density.
The cast VIM ingots and one of each of the HIP'd canisters were heated to forging temperature and then press forged to billets having a cross-section of 1⅝ inches high by 5 inches wide. The ingots of Heats 046 and 047 and the canisters of Heats 881 and 866 were pressed forged from a starting temperature of 1922° F. The ingots of Heats 048, 049, and 050 and the canisters of Heats 869, 870, and 868 were pressed forged from a starting temperature of 1832° F. The forging temperatures were selected based on the processing described in the US patent and in the Japanese patent application. All heats were press forged using ½-inch increments per pass and ½-hour reheats between passes. The cast VIM heats were single end forged and the powder metallurgy heats were double-end forged.
The press forged billets were then hot rolled to ¾-inch thick plate using the same hot-working temperatures described above for the press forging. The hot rolling was conducted with ⅛-inch increments per pass with a 20-30 minute reheat between passes. Following the conversion to ¾-inch thick plate material, each heat was annealed as follows. Heats 046, 047, 881, and 866 were heated at 1922° F. for 1 hour and then water quenched. Heats 048-050 and 868-870 were heated at 2012° F. for 1 hour and water quenched.
The cast VIM heats, 046, 048, 049, and 050 all experienced significant hot tearing during forging. Following the hot rolling to plate, those same heats experienced additional significant hot tearing. In particular, heat 050 broke-up during the first hot-rolling pass and the hot tearing of heat 049 became so pronounced that it was not possible to obtain blanks for mechanical and corrosion testing. Heat 047 was successfully forged and hot rolled. However, that result is attributable to the presence of ferrite in the microstructure. Consequently, heat 047 is not considered a truly austenitic grade. All of the powder metallurgy heats, 881, 866, 868, 869, and 870 were successfully forged and hot rolled. Heat 866 also had a duplex (austenite+ferrite) microstructure.
Triplicate notched tensile, smooth tensile, and Charpy V-notch test specimens were cut and machined from the plate material of each heat in accordance with the standard requirements for such test specimens. The notched tensile specimens were prepared using a stress concentration factor, K t , of 8.0. All tensile and Charpy samples were tested at room temperature in accordance with standard ASTM requirements.
Blanks for bend testing were sectioned along the long axis of the plate material to yield three ¼ inch×¾ inch×3¼ inch blanks that were subsequently fabricated into standard Strauss coupons as described above. Triplicate bend tests were performed using a ⅜-inch mandrel that bent the sample through a 1 9/16-inch slot with a 1,200 psi hydraulic ram. Upon completion of the testing the bend angle was measured.
Six (6) Huey corrosion blanks each measuring 3/16 inch×¾ inch×1⅝ inches were prepared. The blanks were subsequently fabricated into standard Huey corrosion coupons. Triplicate tests were run in boiling 65% nitric acid for five 48 hour time periods per the requirements of ASTM A262-C (Huey test). One untested coupon was tested for immersion density per ASTM B311 at room temperature in order to facilitate corrosion rate calculations.
The results of the longitudinal and transverse, room temperature, tensile testing are reported in Tables IV-VII including the 0.2% offset yield strength (0.2% YS), the ultimate tensile strength (UTS), and the notched tensile strength (NTS) all in ksi, the NTS/UTS ratio, the percent elongation in four diameters (% El.), and the percent reduction in area (% R.A.). The results of room temperature Charpy V-notch (CVN) testing in ft-lbs are shown in Table VII.
Examination of the data in Tables IV to VIII shows that the strength, ductility, and toughness of the powder metallurgy heats are consistently better than the same properties of the cast/wrought heats. This behavior is graphically depicted in FIGS. 9 (0.2% YS), 10 (UTS), 11 (% El.), 12 (% R.A.), and 13 (CVN impact toughness). FIG. 14 , which is a plot of CVN toughness versus UTS clearly shows the superior combination of strength/toughness of the powder metallurgy materials relative to the cast/wrought materials.
TABLE IV
Long. Annealed Tensile Properties
Heat
Composition
Strength (ksi)
NTS/UTS
Ductility
Number
Cr
Ni
Mo
B
Gd
B Eq
Test
0.2% YS
UTS
NTS
Ratio
% El.
% R.A.
046
22.12
18.56
2.78
0.39
0.42
2.22
1
37.5
85.1
95.9
1.13
32.9
42.9
2
38.4
85.8
96.8
1.14
31.2
36.7
3
39.3
83.6
94.7
1.12
30.8
29.7
Avg.
38.4
84.8
95.8
1.13
31.6
36.4
881
22.12
18.25
2.88
0.40
0.44
2.31
1
42.2
96.9
114.2
1.18
37.3
51.1
2
42.5
96.9
115.1
1.19
35.4
48.8
3
43.4
96.7
115.7
1.19
37.7
48.4
Avg.
42.7
96.8
115.0
1.19
36.8
49.4
047
18.12
10.35
4.13
0.12
0.32
1.51
1
40.1
90.2
112.0
1.24
49.7
56.3
2
40.0
90.7
109.9
1.22
50.7
59.9
3
42.6
89.5
110.7
1.23
48.0
49.1
Avg.
40.9
90.1
110.9
1.23
49.5
55.1
866
18.16
10.16
4.22
0.26
0.27
1.43
1
41.0
101.9
125.8
1.24
48.6
66.6
2
41.7
101.9
120.4
1.18
47.2
59.2
3
41.5
101.6
121.1
1.19
46.1
53.4
Avg.
41.4
101.8
122.4
1.20
47.3
59.7
TABLE V
Trans. Annealed Tensile Properties
Heat
Composition
Strength
NTS/UTS
Ductility
Number
Cr
Ni
Mo
B
Gd
B Eq
Test #
0..2% YS
UTS
NTS
Ratio
% El
% R.A.
046
22.12
18.56
2.78
0.39
0.42
2.22
1
37.5
81.8
93.8
1.15
24.9
25.5
2
38.4
82.3
90.6
1.11
27.8
28.8
3
37.9
81.6
91.6
1.12
27.8
28.8
Avg.
37.9
81.9
92.0
1.12
26.8
27.7
881
22.12
18.25
2.88
0.40
0.44
2.31
1
43.7
97.0
113.7
1.17
39.0
55.2
2
43.0
97.3
113.6
1.17
39.5
55.1
3
42.9
97.4
114.3
1.18
37.3
46.2
Avg.
43.2
97.2
113.9
1.17
38.6
52.2
047
18.12
10.35
4.13
0.12
0.32
1.51
1
42.0
91.0
109.8
1.20
45.5
42.7
2
42.1
91.2
108.2
1.19
42.4
33.3
3
42.9
91.3
107.6
1.18
41.1
35.8
Avg.
42.3
91.2
108.5
1.19
43.0
37.3
866
18.16
10.16
4.22
0.26
0.27
1.43
1
53.5
105.7
116.1
1.11
34.6
34.3
2
48.4
104.2
114.3
1.09
48.2
64.6
3
49.7
105.1
116.5
1.11
47.7
64.7
Avg.
50.5
105.0
115.6
1.10
43.5
54.5
TABLE VI
Long. Annealed Tensile Properties
Heat
Composition
Strength
NTS/UTS
Ductility
Number
Cr
Ni
Mo
B
Gd
B Eq
Test
0..2% YS
UTS
NTS
Ratio
% El
% R.A.
048
20.22
11.62
0.06
0.62
0.79
4.06
1
37.9
84.3
84.7
0.99
30.0
29.1
2
39.9
85.3
84.8
1.00
25.0
24.7
3
38.1
85.9
85.1
1.00
26.5
27.9
Avg.
38.6
85.2
84.9
1.00
27.2
27.2
869
20.44
11.73
0.11
0.62
0.66
3.49
1
37.5
101.3
102.0
1.01
38.4
42.4
2
37.2
100.6
101.0
1.00
33.7
29.8
3
36.9
101.0
101.3
1.00
38.1
48.4
Avg.
37.2
101.0
101.4
1.00
36.7
40.2
049
20.66
11.64
<0.01
1.10
0.46
3.10
(Could not be tested, ¾″ plate
had too many hot tears)
870
20.76
11.64
<0.01
1.14
0.54
3.49
1
43.9
110.6
109.6
0.99
30.1
34.3
2
44.3
110.7
109.5
0.99
27.3
27.0
3
44.2
110.4
109.7
0.99
28.8
30.4
Avg.
44.1
110.6
109.6
0.99
28.7
30.6
050
20.34
15.14
4.05
0.54
0.33
1.98
(Could not be tested, billet
broke-up on first pass to plate)
868
20.52
15.16
4.13
0.58
0.26
1.71
1
44.5
102.0
119.1
1.17
37.9
52.7
2
45.3
101.9
119.0
1.17
37.3
52.7
3
41.3
101.9
119.6
1.17
35.6
44.6
Avg.
43.7
101.9
119.2
1.17
36.9
50.0
TABLE VII
Trans. Annealed Tensile Properties
Heat
Composition
Strength
NTS/UTS
Ductility (%)
Number
Cr
Ni
Mo
B
Gd
B Eq
Test
0.2% YS
UTS
NTS
Ratio
% El
% R.A.
048
20.22
11.62
0.06
0.62
0.79
4.06
1
38.5
80.1
82.1
1.04
29.0
20.7
2
36.6
77.5
82.1
1.04
16.8
16.3
3
38.6
79.4
83.1
1.05
19.6
22.2
Avg.
37.9
79.0
82.4
1.04
21.8
19.7
869
20.44
11.73
0.11
0.62
0.66
3.49
1
37.9
100.5
98.3
0.98
36.4
27.9
2
37.9
100.5
99.5
0.99
36.4
36.7
3
37.2
100.3
97.1
0.97
36.2
37.0
Avg.
37.7
100.4
98.3
0.98
36.3
33.9
049
20.66
11.64
<0.01
1.10
0.46
3.10
(Could not be tested, ¾″ plate had
too many hot tears)
870
20.76
11.64
<0.01
1.14
0.54
3.49
1
43.7
109.3
107.2
0.98
30.8
36.2
2
44.4
109.2
106.8
0.98
27.6
30.9
3
43.7
109.0
107.7
0.99
28.8
31.5
Avg.
43.9
109.2
107.2
0.98
29.1
32.9
050
20.34
15.14
4.05
0.54
0.33
1.98
(Could not be tested, billet
broke-up on first pass to plate)
868
20.52
15.16
4.13
0.58
0.26
1.71
1
47.0
101.8
118.3
1.16
35.5
40.8
2
46.1
101.8
115.1
1.13
35.4
43.1
3
46.2
102.2
115.2
1.13
36.9
45.5
Avg.
46.4
101.9
116.2
1.14
35.9
43.1
TABLE VIII
CVN Impact Toughness
Heat
B
Gd
Orientation
#1
#2
#3
Avg.
046
0.39
0.42
L-S
30.5
24.2
31.0
28.6
T-L
14.2
17.4
16.9
16.2
881
0.40
0.44
L-S
72.3
70.9
70.9
71.4
T-L
67.7
68.5
65.2
67.1
047
0.12
0.32
L-S
47.4
48.9
50.1
48.8
T-L
32.2
33.3
33.3
32.9
866
0.26
0.27
L-S
85.5
87.3
81.0
84.6
T-L
77.3
72.7
81.8
77.3
048
0.62
0.79
L-S
15.7
15.2
15.7
15.5
T-L
12.5
12.9
12.6
12.7
869
0.62
0.66
L-S
43.9
43.7
44.2
43.9
T-L
37.7
38.5
38.1
38.1
049
1.10
0.46
(Could not be tested, ¾″
plate had too many hot tears)
870
1.14
0.54
L-S
33.0
34.5
32.2
33.2
T-L
27.3
27.2
27.4
27.3
050
0.54
0.33
(Could not be tested, billet
broke-up on first pass to plate)
868
0.58
0.26
L-S
58.0
59.1
57.5
58.2
T-L
47.3
47.6
49.8
48.2
TABLE IX
Corrosion Test Results
Heat
Composition (w/o)
Test Data (mpy)
Average Rate
Number
Cr
Ni
Mo
B
Gd
B Eq
Test #
Rate #1
Rate #2
Rate #3
Rate #4
Rate #5
mpy
ipm
Comments
046
22.12
18.56
2.78
0.39
0.42
2.22
1
24.5
82.5
203.7
384.5
448.5
228.7
0.0191
Heavy uniform
2
24.5
83.4
199.2
378.5
468.3
230.8
0.0192
attack on all
3
23.8
75.3
183.6
354.1
466.8
220.7
0.0184
surfaces
881
22.12
18.25
2.88
0.40
0.44
2.31
1
6.3
4.1
4.4
5.4
5.7
5.2
0.0004
Light uniform
2
6.7
4.4
4.4
4.8
5.4
5.1
0.0004
general attack
3
6.3
4.1
4.4
5.0
5.0
5.0
0.0004
on all surfaces
047
18.12
10.35
4.13
0.12
0.32
1.51
1
65.6
911.5
1068
1098
1112
851.0
0.0709
Heavy uniform
2
59.5
878.5
1033
1079
1119
833.8
0.0695
attack on all
3
55.5
812.0
1047
1094
1085
818.7
0.0682
surfaces
866
18.16
10.16
4.22
0.26
0.27
1.43
1
10.3
11.6
19.6
28.4
39.4
21.9
0.0018
Moderate
2
9.3
11.4
17.9
28.2
37.6
20.9
0.0017
uniform
3
10.4
11.0
18.6
27.8
39.4
21.4
0.0018
general attack
on all surfaces
mpy = mils per year
ipm = inches per month
TABLE X
Huey Corrosion Test Results
Heat
Composition (w/o)
Test Data (mpy)
Average Rate
Number
Cr
Ni
Mo
B
Gd
B Eq
Test #
Rate #1
Rate #2
Rate #3
Rate #4
Rate #5
mpy
ipm
Comments
048
20.22
11.62
0.06
0.62
0.79
4.06
1
136.5
454.4
878.1
941.7
909.0
663.9
0.0553
Heavy uniform
2
123.2
388.4
760.1
1185
936.0
678.5
0.0565
attack on all
3
134.1
452.6
848.5
777.4
831.4
608.8
0.0507
surfaces
869
20.44
11.73
0.11
0.62
0.66
3.49
1
11.1
7.1
8.5
9.9
10.4
9.4
0.0008
Light uniform
2
12.2
8.5
8.6
9.4
9.8
9.7
0.0008
general attack
3
11.7
7.0
8.7
9.2
9.5
9.2
0.0008
on all surfaces
049
20.66
11.64
<0.01
1.10
0.46
3.10
1, 2 & 3
Could not be tested, ¾″ plate had too many hot tears
870
20.76
11.64
<0.01
1.14
0.54
3.49
1
17.5
18.0
18.7
20.5
20.4
19.0
0.0016
Moderate
2
17.5
17.6
19.3
20.0
20.9
19.1
0.0016
uniform general
3
17.3
18.0
19.2
20.3
20.3
19.0
0.0016
attack on all
surfaces
050
20.34
15.14
4.05
0.54
0.33
1.98
1, 2 & 3
Could not be tested, billet broke-up on first pass to plate
868
20.52
15.16
4.13
0.58
0.26
1.71
1
9.6
8.4
11.8
17.0
19.4
13.2
0.0011
Light uniform
2
9.3
8.4
11.1
17.3
20.2
13.3
0.0011
general attack
3
9.7
8.4
12.0
17.3
20.3
13.5
0.0011
on all surfaces
mpy = mils per year
ipm = inches per month
The results of the Huey corrosion testing set forth in Tables IX (cast/wrought heats) and X (powder metallurgy heats) show pronounced and significant differences between the two types of material. In all cases the Huey corrosion rates of the powder metallurgy material are lower and more stable (i.e., the corrosion rate does not increase appreciably with successive 5 hour test periods). The significant difference in corrosion behavior between the powder metallurgy heats and the cast/wrought heats is graphically depicted in FIG. 15 . That difference is completely unexpected since the two sets of heats do not appear to differ significantly with respect to alloy composition. It should also be noted that of the three cast/wrought heats that could be tested, Heat 047 exhibited the worst Huey corrosion rate, and that behavior is attributed to the observed presence of ferrite in the matrix material of the alloy.
The metallographic results presented in FIGS. 16-25 qualitatively show the differences in the size and distribution of the second phase boride and gadolinide particles between the cast/wrought heats ( FIGS. 16A , 16 B, 18 , 20 A, 20 B, 22 A, 22 B, and 24 ) and the powder metallurgy processed heats ( FIGS. 17 , 19 , 21 , 23 , and 25 ). Compared to the cast/wrought heats, the annealed microstructures of the powder metallurgy heats show smaller and more uniformly distributed borides and gadolinides without pronounced alloy segregation.
It will be recognized by those skilled in the art that changes or modifications may be made to the above-described embodiments without departing from the broad inventive concepts of the invention. It is understood, therefore, that the invention is not limited to the particular embodiments that are described, but is intended to cover all modifications and changes within the scope and spirit of the invention as described above and set forth in the appended claims. | A corrosion resistant, neutron absorbing, austenitic alloy powder is disclosed having the following composition in weight percent.
C
0.08 max.
Mn
up to 3
Si
up to 2
P
0.05 max.
S
0.03 max.
Cr
17-27
Ni
11-20
Mo + (W/1.92)
up to 5.2
B Eq
0.78-13.0
O
0.1 max.
N
up to 0.2
Y
less than 0.005
The alloy contains at least about 0.25% B, at least about 0.05% Gd, and the balance of the alloy composition is iron and usual impurities. B Eq is defined as % B+4.35×(% Gd). An article of manufacture made from consolidated alloy powder is also disclosed which is characterized by a plurality of boride and gadolinide particles dispersed within a matrix. The boride and gadolinide particles are predominantly M 2 B, M 3 B 2 , M 3 X, and M 5 X in form, where X is gadolinium or a combination of gadolinium and boron and M is one or more of the elements silicon, chromium, nickel, molybdenum, iron. | 2 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to a cargo bar that is installed between the side walls of vans and trucks to stabilize a load being hauled.
BACKGROUND OF THE INVENTION
[0002] The cargo bar is an elongate tube having a pressure pad at each end. The length is adjustable to adapt to the distance between walls and includes a lock for locking the tube length at an adjusted position. In use, a truck or van is partly loaded, front to back, and a cargo bar is placed against the partial load and extended between the side walls. The bar is extended to force the pads into tight engagement with the side walls and locked to secure the bar at that position. The partial load is thereby tightly held in place to avoid shifting as the van or truck is driven to a port of destination.
[0003] The present invention is intended to improve on the existing cargo bars in at least three categories.
[0004] Bar Length
[0005] The distance between the side walls of the van is about 8 feet. The bar length prior to the extension needs to approximate that length to provide convenient handling and installation. One needs to be able to place one end of the bar with the pad abutted against a side wall and then the bar is extended to place the other pressure pad at th other side wall. Whereas the different containers have similar but not the same width, the collapsed bar length is typically on the order of 7 feet (e.g., 7′ 2″ to 7′ 4″) with a foot or so of available extension. However, the 8 foot length is cumbersome for handling, shipping and storage of large quantities of the cargo bars, i.e., as the product moves from the factory to the truck owner/user. Whereas 4 foot pallets are common for handling quantities of products in general, the 7 foot length cargo bars hang about 1½ feet off both ends of a standard 4 foot pallet adding to the cost of handling, shipping and storage.
[0006] Bar Weight and Cost
[0007] The bar is subject to substantial stress and the bar must be anchored securely in place against the wall to avoid being dislodged by a shifting load. Most prior bars are cylindrical tubes constructed of steel that is both heavy and expensive. It is desirable to maintain the bar strength but to lessen the cost.
[0008] Gripping Mechanism
[0009] Gripping is provided by the pressure pads as discussed. The pads are flat and rigid with a configured elastomeric gripping surface. The pads are extended against the walls by a ratchet mechanism that is cumbersome and heavy. The gripping surface of the pads may not be secure in part because the walls against which the pads are pressed become slightly bowed under the pressure and this results in a curved wall surface with less surface area of the flat pressure pads being in contact with the wall. It is desirable to provide a pressure pad that more tightly abuts the wall and with a less cumbersome and more secure mechanism for extending the bar.
BRIEF DESCRIPTION OF THE INVENTION
[0010] The preferred embodiment of the invention is made of three square tubes that are assembled in telescoping relation. All three tubes are less than four feet in length and when assembled and in a collapsed condition do not exceed four feet in length. The square tubes are inherently stronger and can be made lighter with a thinner wall material to substantially reduce the cost. The first and second tube sections are provided with a lock mechanism that locks the first and second tube sections together in an extended relation. The extended position will likely be the preferred position and likely maintained throughout use in mounting and demounting the bar for securing a load. The telescoping action between the first and second tube sections is intended primarily to facilitate shipping and handling. However, the option of collapsing the bar to 4 feet is available simply by depressing the locking pins.
[0011] The second and third tubes remain in telescoping relation with the second tube section. A lever is mounted at the end of the second tube section into which the third tube moves in and out. The lever carries an elliptical pinion gear with peripheral teeth positioned for engagement with rack-like teeth formed in the corresponding side of the third tube and along a substantial length thereof. With the lever pivoted to its full unlocked position, the pinion teeth are disengaged from the rack teeth and the third tube can be fully extended into contact with a van or truck wall. The lever is pivoted to cause engagement of the pinion teeth with the rack teeth and as the lever continues to pivot, the third tube is forced outwardly into tight engagement with the wall. The elliptical configuration assures secure engagement of the teeth at the point of greatest resistance. A latch mechanism is engaged by the lever upon full extension to maintain the right engagement with the walls. A release is engaged by the user to achieve unlocking and removal of the bar as desired.
[0012] The pressure pads of the preferred embodiment have a rigid center defined by the cross section of the tube, but the side areas surrounding the centers are adapted to slightly bow under the pressure of the lever induced extension. Thus, as the track or van wall is bowed, the bowed configuration is matched by the pressure pads to provide full surface-to-surface engagement.
[0013] The pads are provided with a nesting arrangement to enhance stacking of the multiple cargo bars for shipping and storage. A second embodiment of the cargo bar includes extendable pins that penetrate through the pad center to engage tracks mounted to the track or van walls as an alternate application of the cargo bars. Other improvements will become apparent upon reference to the following detailed description having reference to the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
[0014] [0014]FIG. 1A illustrates in perspective view a quantity of cargo bars in accordance with the invention as stacked on a pallet, and FIG. 1B is a top view and FIG. 1C is a front view showing in greater detail the nesting arrangement of the cargo bars as stacked in FIG. 1A;
[0015] [0015]FIG. 2 is a rear view of a truck box containing a partial load and a cargo bar in accordance with the invention secured to the walls of the truck box to secure the partial load.
[0016] [0016]FIG. 3 is an exploded view of a cargo bar in accordance with the present invention, and FIG. 3A is a top view of a cargo bar section as viewed on view lines 3 A- 3 A of FIG. 3;
[0017] [0017]FIG. 4 is a view showing the components of FIG. 3 in assembled relation as when stored and shipped;
[0018] [0018]FIG. 5 is a view showing the components of FIG. 3 in assembled relation as when securing a partial load in a truck box;
[0019] [0019]FIG. 5A is a section view as taken on sections lines 5 A- 5 A of FIG. 5 and FIG. 5B is an alternate view of FIG. 5A, i.e., showing the lock disengaged and engaged;
[0020] [0020]FIG. 6 is an enlarged perspective view of the mechanism for tightening the cargo bar in a truck box and FIGS. 6 A- 6 E sequentially illustrate the cargo bar of FIG. 5 in the process of being secured to the walls of a truck box by the mechanism of FIG. 6; and
[0021] [0021]FIGS. 7, 7A, 8 and 8 A are views illustrating an alternate embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] [0022]FIG. 1A schematically illustrates a number of cargo bars 10 loaded on a pallet 12 following manufacture. The loaded pallets are conveyed through commerce in the usual manner, i.e., stacked together on the pallet and the loaded pallets transferred to a warehouse, subsequently loaded onto trucks and hauled to a point of distribution. There it may be stored for a period of time and then shipped to a retail outlet or directly to a trucking company. FIGS. 1B and 1C are top and front views where it can be seen that the pressure pads 14 have protrusions 16 and mated recesses 18 that interfit to facilitate stacking of the cargo bars on the pallet 12 .
[0023] It is desirable that the cargo bars fit a 4 foot pallet which is common for moving products through commerce and the present invention provides for shortening of the cargo bar length for shipping purposes to accommodate the conventional length of a pallet, i.e., four feet. The ability to load the bars on a 4 foot pallet results in reduced cost in shipping and storing of the cargo bars.
[0024] Reference is now made to FIG. 2 illustrates the use of the cargo bar of the invention for its intended purpose, i.e., securing loads. Illustrated is a truck box 20 in which freight items 21 are loaded. It is desirable upon many occasions to secure such partial loads against undesired shifting. The width of the box 20 is in the order of 8 feet between walls 22 and it is typically desirable that the bars 10 are sufficiently long to approximate the width (e.g., about 8 feet in length) but with a telescoping tube end 28 that is extended into abutting engagement with the opposing walls 22 . More precisely, the bar length is forcibly extended to exert pressure against the walls and prevent dislodgement.
[0025] It will thus be understood that the cargo bar 10 is first desired to be a length of no greater than 4 feet to fit onto the pallet 12 but then when put in use, to have an approximate permanent length of about 8 feet for ready mounting to the width span of a truck box.
[0026] Reference is now made to FIGS. 3 - 5 . FIG. 3 shows three tubes which include an outside or large tube 24 , a middle tube 26 that is slidable inside the large tube 24 , and an inside tube 28 that is slidable inside the middle tube 26 . As noted, tube 24 includes a pressure pad 14 at its distal or outside end and a hole 30 strategically placed near its opposite end. The middle tube 26 is sized to fit inside tube 24 . Tube 26 has a spring loaded pin 32 at its inserted end that is sized to fit hole 30 of tube 24 . At the opposite end, tube 26 is fitted with a lever 34 pivotally mounted to a bracket 36 at the tube end. Tube 28 is sized to fit inside tube 26 and its distal end is fitted also with a pressure pad 14 .
[0027] [0027]FIG. 4 illustrates the tubes 24 , 26 and 28 as assembled into its fully collapsed relation and as so assembled is sized to fit a conventional pallet, e.g., 4 feet in length and width. The pin 32 is compressed into tube 26 as seen in FIG. 5A. FIG. 5 illustrates the cargo bar in a second assembled relation for operative use, i.e., securing a load as illustrated in FIG. 2. As will be noted, tube 26 is extended from tube 24 to a position whereat pin 32 is protruded into hole 30 (the position of FIG. 5B). This provides sufficient overlap to insure a rigid tube length from pad 14 on tube 24 to bracket 36 on tube 26 . The tube 28 can be positioned at any position of extension from tube 26 as will now be explained.
[0028] [0028]FIG. 3A illustrates a top view of tube 28 taken on view lines 3 A- 3 A of FIG. 3. Rack-like teeth 38 are provided as a double row of teeth along a substantial portion of the length of tube 28 as seen in FIG. 3A. The rack-like teeth 38 are engaged by pinion teeth 40 of lever 34 as seen in FIG. 6. As shown in FIG. 6A, the lever 34 is pivoted to its initial position where the pinion teeth 40 are not engaged with the teeth 38 of tube 28 . The tube 28 can now be extended to a desired position of extension, i.e., substantially the distance between the side walls 22 .
[0029] As the lever 34 is raised or pivoted to its inboard position (see FIG. 6B), the teeth 40 engage teeth 38 and continued pivoting of lever 34 causes the pinion teeth 40 to sequentially engage rack teeth 38 and force further outward or extended movement of tube 28 relative to tube 26 as illustrated by the arrows 49 in FIG. 6.
[0030] With reference to FIGS. 6 C- 6 E, it will be noted that locking slot 42 on lever 34 engages lock stem 44 on latch 46 to force pivoting of latch 46 against the bias of spring (not shown) until the stem 44 is caused to seat in slot 42 by spring action of the spring. At this point the spring holds the stem 44 in slot 42 and the lever 34 is locked into the position of FIG. 6E. Unlocking is achieved by pressing latch 46 downward against the bias of the spring (note arrow 50 ). As previously discussed, the pinion teeth 40 are configured somewhat elliptical and as the lever is pivoted from the position of FIG. 6C to FIG. 6E, a progressively greater force is exerted by the pinion gear against the rack teeth to insure a forced engagement of teeth 40 with teeth 38 .
[0031] Reference is now made to FIGS. 7, 7A, 8 and 8 A illustrating an alternate embodiment of the invention. Whereas the cargo bar is typically designed to establish gripping through compression of pressure pads against the truck or van box walls, an alternate design is the provision of spaced horizontal tracks secured or formed in the side walls of the truck or van at frequent intervals along the length of the truck box. In this alternative embodiment, the pressure pads are augmented with retractable pins that fit the horizontal track. The pins need only extend into the tracks where they are supported at a desired elevation by the track. Pressure gripping is less necessary and the general structure of a track system of load securement is known to the art.
[0032] The alternate embodiment of FIGS. 7A and 8 provides for adaptation of the preferred embodiment disclosed in FIGS. 1 - 6 to also function in the track-type system of load securement. With reference to FIG. 7, it will be noted that a metal track pin 52 (configured to fit the track) is inset into the tube 54 . Pressure pad 56 is thus available for gripping a side wall in the manner discussed above. However, should the cargo bar be applied to a track or van box equipped with the guide tracks, the track pins are extended from the tube 54 as shown in FIG. 8.
[0033] As noted, the track pins 52 include a mounting slot 58 that permits sliding of the track pin relative to mounting pin 60 . The track pin 52 is mounted on a cylindrical slide member 62 contained in the tube 54 . A rod 68 connected to slide member 62 extends laterally through a J slot 64 in tube 54 . A compression spring 66 urges the slide member 62 and thus the track pin 52 through a hole in the pad 56 as illustrated in FIG. 8. The J slot 64 is shown in FIGS. 7A and 8A. It will be observed that the rod 68 is located at the bottom of the J slot in FIGS. 7 and 7A (to the left) and the rod 68 is located at the top of the J slot in FIGS. 8 and 8A (ro the right). This positioning is accomplished manually. The rod 68 is manually forced down the tube slot and against the spring pressure of spring 66 to withdraw the track end 52 as shown in FIGS. 7 and 7A. The spring urges the rod against the short side of the J slot to retain the track pin in the withdrawn position. Again by manual movement, the rod 68 is forced down around the curve of the J slot to the long side where the spring now urges the rod 68 to the top of the slot with the track pin 52 extended as shown in FIG. 8. Readers will appreciate that a similar arrangement is provided at both ends even though shown for one end only in FIGS. 7 and 8.
[0034] It will be appreciated that the preferred embodiment of the invention employs three tube components to enable reduction of the bar length to a length suitable for handling and storing of the bars on a conventional 4 foot pallet. However, a number of the improvements as explained apply to a bar having two tube sections or components. Such would not fit the 4 foot pallet but can include the improved pressure pads, square tube configuration, the rack and pinion lever mechanism and the conversion of the bar to the track type cargo bar as viewed in FIGS. 7 and 8.
[0035] The invention encompasses the broad definition of the claims appended hereto with the understanding that the claim terms are intended to have their common meaning is understood generally by persons in the art. In particular, the invention is not limited to the embodiments herein disclosed. | A cargo bar having reduced costs due in part to being constructed from square tubes and due to being collapsible to a length that fits a 4 foot pallet so as to facilitate shipping and storage. Pressure induced extension of the cargo bar against opposed truck walls is provided by a rack and pinion gear arrangement, the rack teeth provided on a first tube wall and the pinion teeth provided on a pivotal lever mounted to a second tube. The bar ends have pressure pads that will conform to side walls of a truck or van and the tube interior is alternately fitted with retractable track pins that extend through the pads and retract behind the pads to accommodate different cargo bar systems. | 1 |
TECHNICAL FIELD
The present invention relates to the use of wireless telephones and, particularly, to limiting such use under circumstances presenting safety hazards.
BACKGROUND OF RELATED ART
With the globalization of business, industry and trade wherein transactions and activities within these fields have been changing from localized organizations to diverse transactions over the face of the world, the telecommunication industries have, accordingly, been expanding rapidly. Wireless telephones and, particularly, cellular telephones have become so pervasive that their world wide number is fast approaching one hundred million or more. While the embodiment to be subsequently described relates to cellular telephones, the principles of the invention would be applicable to any wireless personal communication device which could be used to communicate from the inside of an automobile. These would include the wide variety of currently available communicating personal palm devices or Personal Digital Assistants (PDAs), which include, for example, Microsoft's WinCE line; the PalmPilot line produced by 3Com Corp.; and IBM's WorkPad. These devices are comprehensively described in the text, Palm III & PalmPilot, Jeff Carlson, Peachpit Press, 1998.
Unfortunately, the use of wireless telephones by drivers of automobiles have been related to an increasing number of automobile accidents. The cellular phone not only requires the use of one or even both of the driver's hands, but also diverts the driver's attention from driving. The problem has become so pronounced that many states and countries have enacted, or are considering the enactment, of legislation banning the use of cell phones by drivers in moving vehicles. Such legislation has been opposed by many who regard it as too intrusive on drivers, as well as too difficult to enforce. However, the problem may be expected to become more pronounced along with the progress of the philosophy of the mobile office where the worker is available “24 hours a day—seven days a week”.
Consequently, the wireless telephone, as well as the automotive, industries are seeking solutions to these problems for drivers.
SUMMARY OF THE PRESENT INVENTION
The present invention offers a solution to the problem of cell phone use during driving. The solution will require the involvement of legislation or voluntary action by the handheld wireless phone industry to put a sensing means into the wireless telephone which will detect or sense when the telephone is on or in operation, and then provide a sensor which will respond to a wireless turnoff signal sent by the computer control system of the automobile.
Accordingly, the present invention provides an automobile computer control system for limiting the usage of wireless telephones in moving automobiles comprising: wireless means for sensing when the velocity of the automobile exceeds a predetermined velocity; means for sensing when said wireless telephone is in use by the driver of said automobile; and means responsive to both of said sensing means for limiting said use of said wireless telephone by said driver of said automobile when the velocity of the said automobile exceeds said predetermined velocity. For the best safety, the predetermined velocity is any moving velocity. Also, the wireless means for sensing when the velocity of the automobile exceeds a predetermined velocity may be carried out by simple infrared means, which will be described in greater detail hereinafter.
More particularly, the present invention may involve an automobile computer control system for limiting the usage of wireless telephones in moving automobiles comprising: means in said automobile for emitting a signal towards the driver of the automobile when the velocity of the automobile exceeds a predetermined velocity; means on the wireless telephone for sensing said emitted signal when said wireless telephone is in use by the driver of said automobile; and means responsive to said sensing means for limiting said use of said wireless telephone by said driver of said automobile upon the sensing of said emitted signal. As previously stated, the emitted signal is preferably an infrared signal and, particularly, a narrow beam infrared signal directed towards the driver. In this way, the narrow beam signal is sensed only if said cellular telephone is being used by the driver of said automobile. The means for limiting the use of said wireless telephone may turn off the wireless telephone when the velocity of the automobile exceeds the predetermined velocity; or there may be further included means for notifying the driver that the wireless telephone will be turned off after a brief time period after said sensing that the velocity of the automobile has exceeded said predetermined velocity together with means for delaying the turning off of said wireless telephone for that brief time period.
In accordance with an alternative aspect of the invention, the means for limiting the use of said wireless telephone when the velocity of said automobile exceeds said predetermined velocity, includes means for notifying the service provider of said wireless telephone, whereby said service provider may charge higher rates when said velocity exceeds said predetermined velocity. The means for notifying said service provider may also include means for transmitting, along with the voice data during the driver's use of said wireless telephone, additional data indicating that said velocity exceeds said predetermined velocity.
In accordance with another aspect of the present invention, there may be means permitting the receiving of an incoming telephone transmission on said turned off wireless telephone briefly and means for turning off said incoming transmission after a brief predetermined time period.
Finally, so that emergencies may be handled, there may be means for storing a set of emergency telephone numbers, as well as a means for enabling said turned off wireless telephone to call any one of said set of emergency telephone numbers.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be better understood and its numerous objects and advantages will become more apparent to those skilled in the art by reference to the following drawings, in conjunction with the accompanying specification, in which:
FIG. 1 is a partial breakaway diagrammatic side view of a portion of an automobile arranged so as to illustrate the operation of the invention;
FIG. 2 is a partial top view of the arrangement of FIG. 1 from inside of the automobile;
FIG. 3 is a diagrammatic illustration of a cell phone operation used in the embodiment of the invention;
FIG. 4 is a block diagram of a generalized data processing system including a processor unit which provides the onboard automobile computer control for the present invention; and
FIG. 5 is a flowchart of the steps involved in applying the system of the present invention to limit the usage of wireless telephones by the driver of a moving automobile.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, there is provided a diagrammatic side view of a potion of an automobile 10 in which a driver 11 is using a wireless cell phone 12 . FIG. 2 is a fragmentary top view of the same elements. A conventional (under ten feet) infrared system is used. Source or emitter 14 emits a narrow beam IR signal at the driver's head, which is usually within two to five feet from the emitter 14 . The narrow beam, at that point, need be no more than two feet in diameter. The wireless telephone 12 has an IR port 13 through which emitter 14 may beam data to the telephone. It should be noted that such IR communication ports are already available on most of the currently available wireless communicating personal palm devices or PDAs that were mentioned above.
In order for the present invention to function, such IR ports would have to be added to cellular telephones. Since many of the current and planned cellular phones will be performing a variety of the functions of these communicating PDAs, the IR ports on the cell phones of this invention would be available for such other functions.
Such IR ports are described in detail in the text, Personal Computer Secrets, Bob O'Donnell, IDG Books Worldwide Inc., Foster City, Calif., 1999, page 215. The IR signals should conform to the IrDA (Infrared Data Association) standard of at least 1.15 Mbps; but, preferably, about 4 Mbps (FastIrDA). The functioning of the IR ports on wireless palm-type devices, which may function as port 12 , are described further in the text, How to Do Everything with Your Palm Handheld, Dave Johnson et al., 2000, Osborne/McGraw-Hill, Berkeley, Calif., particularly at pp. 84-90.
When cell phone 12 is in use, the IR port 13 is turned on. As will be described hereinafter in greater detail, the computer control system in the automobile monitors the velocity of the auto to sense when the auto velocity exceeds a preset level, at which the use of a cell phone is determined to present a danger. A reasonable default value is zero velocity, i.e. the use of a cell phone is unsafe at any speed. In such a case, if the vehicle is moving, then emitter 14 will emit a signal within narrow IR beam 15 which will turn off the cell phone immediately or after a warning and a short delay.
With respect to FIG. 3 there will be described, for background, a simplified typical wireless cell phone 12 transmission to/from and automobile 10 . There is shown a generalized diagrammatic view of a portion of a Public Switched Telephone Network (PSTN) 25 showing channel paths to and from the wireless cell phone 12 . Mobile or cellular telephones 12 are connected via wireless air interface transmission paths 20 to cell receiving/transmission antenna 21 at site 22 . It will also be understood that each illustrative cell site 22 will have many cellular phones with wireless connectability to the respective site. There is a base station 23 respectively associated with site 22 for achieving transmitting/receiving RF communications via the air interfaces 20 to the cellular device 12 . The base station 23 is connected to mobile switching center 24 . This mobile switching center 24 has many wireless phones connected to it. The center operates to control the channel connections, i.e. switch into and out of the PSTN 30 , those calls originated or terminated at the mobile telephones, e.g. cell phone 12 . Switching center 24 connects channels from the cellular phone 12 and others into the PSTN 25 .
Now, with reference to FIG. 4 there will be described a typical computer control system which may function as an automobile onboard controller for various automotive functions, including the control of wireless telephone use in a moving automobile. A central processing unit 30 is provided and interconnected to various other components by system bus 32 . An operating system 35 , which runs on processor 30 , provides control and is used to coordinate the functions of the various components of the control system. The OS 35 is stored in Random Access Memory (RAM) 31 , which in a typical automobile control system has from four to eight megabytes of memory. The programs for the various automobile monitor and control functions are now permanently stored in Read Only Memory (ROM) 33 , and moved into and out of RAM to perform their respective functions. This includes the cell phone use control programs of the present invention. The automobile is likely to have a display 43 controlled through display adapter 42 to provide information to the driver. The vehicle control system monitors a wide variety of automobile parameters through representative sensors/ monitors 36 and 37 connected to the processor 30 through their respective I/O adapters 36 and 37 . This sensed data is processed and the appropriate responsive control signals are distributed through adapter 45 . In the operation of the present invention, when the control system gets feedback through a monitor that the vehicle velocity has exceeded the predetermined maximum for cell phone use, then an appropriate stop phone IR signal is sent out through IR adapter 40 via IR emitter 44 which is received by IR port 13 of wireless phone 12 in FIG. 1 .
The running of an illustrative control process, in accordance with the present invention, will now be described with respect to FIG. 5 . Initially, a maximum velocity at which the cell phone may be used in the automobile is set, step 50 . Let us assume that the default maximum velocity set here by the manufacturer is any velocity greater than zero. However, there may be a provision for the user or any authority controlling cell phone use to adjust such a default maximum velocity. An initial determination is made as to whether the cell phone is in use, step 51 . If No, the process is returned to initial step 51 where cell phone use is awaited. If the determination in step 51 is Yes, there is cell phone use, then a further determination is made as to whether the maximum velocity for such use has been exceeded, step 52 . If No, the process is returned to step 52 where the velocity continues to be monitored. If Yes, the maximum velocity has been exceeded, then, step 53 , a further determination is made as to whether the current phone call is an emergency call. As set forth hereinabove, the user is permitted to list and store a set of emergency numbers such as 911, EMS and Fire services. The call will be compared to this list before being cancelled by the system. Thus, a Yes determination will return the process to step 53 where the emergency call is monitored until terminated. If the decision from step 53 is No, there is no emergency call, then the user is warned that the call will be terminated in a preset number of seconds, step 54 . The warning may be a conventional verbal warning over the cell phone, e.g. “This call will be terminated in 15 seconds unless the automobile is stopped.”.
This warning, as well as the terminating of the call, may be done simply and directly, e.g. when the maximum velocity for phone use is exceeded, the IR beam is sent irrespective of cell phone use. Then, if the cell phone is in use, the IR port in the phone will be triggered and the delay, as well as the termination of the call, will be carried out by a routine in the phone. This simple approach would be effective for operations where the cell phone is not to be used at any velocity. Thus, if the auto is moving, the IR signal is sent. There is no need for any setting input and control within the automobile's computer system. However, if any sort of maximum velocity control is to be practiced, then it is desirable to have a program in the cell phone controlling the velocity settings, the warning, the delay timeout and the termination of the call. In this operation, the automobile's computer control system would encode the auto's velocity into the beamed IR signal which would be decoded at the cell phone and compared to the maximum velocity already encoded into the cell phone. The result would trigger appropriate warning and termination. With this programming done in the cell phone, the cell phone service provider would be able to update the cell phones firmware, e.g. flash ROM to provide for changes in the permitted maximum velocity. This approach also makes it possible for the service provider to provide for different maximum velocities in different cities or states by simply transmitting new operating parameters over the cellular network.
A determination is then made as to whether the delay period has timed out, step 55 . A No returns the process to step 55 where the timeout is awaited. A Yes turns the cell phone off and the process is returned to initial step 51 where another use of the cell phone is awaited.
In a variation of the control of cell phone use, the user may be charged at a very high rate by his cell phone service provider for use of the phone at velocities above the maximum. This option is shown by the dashed line path in FIG. 5 after a Yes decision in step 52 that the maximum velocity had been exceeded. The cell phone is not turned off but the time at a velocity exceeding the maximum is recorded, step 57 , that time is provided to the service provider for billing purposes, step 58 , and the process is returned to step 52 where the velocity continues to be monitored to determine if it continues to be in excess of the maximum velocity.
Although certain preferred embodiments have been shown and described, it will be understood that many changes and modifications may be made therein without departing from the scope and intent of the appended claims. | An automobile computer control system for limiting the usage of wireless telephones in moving automobiles comprising an implementation for sensing when the velocity of the automobile exceeds a predetermined velocity, a wireless implementation for sensing when said wireless telephone is in use by the driver of said automobile and a function responsive to both of said sensing implementations for limiting said use of said wireless telephone by said driver of said automobile when the velocity of the said automobile exceeds said predetermined velocity. For the best safety, the predetermined velocity is any moving velocity. Also, the wireless device for sensing when the velocity of the automobile exceeds a predetermined velocity may be carried out by simple infrared device. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of application Ser. No. 10/099,685, titled “Custom Fit Sale of Footwear” and filed Mar. 14, 2002. application Ser. No. 10/099,685, in its entirety, is incorporated by reference herein. This applcation is related to U.S. Pat. No. 5,714,098 to Daniel R. Potter, issued Feb. 3, 1998, which patent is incorporated entirely herein by reference. This application is also related to U.S. Pat. No. 5,879,725 to Daniel R. Potter, issued Mar. 9, 1999, which patent is incorporated entirely herein by reference as well.
FIELD OF THE INVENTION
[0002] The invention relates to the sale of custom-fitted footwear. More particularly, the invention relates to a method and data structure for selling footwear to individual customers. With the invention, a customer selects footwear based upon the last used to manufacture the footwear, so that the customer obtains footwear custom-fitted for the customer's feet.
BACKGROUND OF THE INVENTION
[0003] Consistently obtaining footwear that fits properly has long been a problem for footwear customers. Similarly, footwear manufacturers have long sought to ensure that customers receive properly fitting footwear, in order to maintain their customers' satisfaction. Even with modern technology, however, this goal has proven elusive. One problem with sizing footwear is that different models of footwear are typically manufactured using different lasts. Even if two different models of footwear are made by the same manufacturer and are labeled as the same size, they may still have different shapes. Thus, a customer who may be comfortable with the fit of a first model of footwear in, for example, a size 9 length and a size D width may not enjoy the fit of a second, different model of footwear having the same length and width sizes. For that second model of footwear, the customer may instead find that a size 8½ length and size E width provides the most comfortable fit.
[0004] Because of this inconsistency in the sizing of footwear, many potential footwear customers are reluctant to buy footwear without trying it on first to ensure a proper fit. These customers will not purchase footwear through the mail, by telephone, over the Internet, or through any other form of remote communication. Unfortunately, shoe manufacturers cannot make their footwear physically available in all possible models and sizes to all potential customers. For footwear manufactures that offer even a small range of footwear models, the cost of providing a sample of each model in each size to every footwear retailer would be prohibitively expensive. Further, most footwear retailers would not have the space to store and display a sample of each footwear model in each available size for more than a handful of footwear manufacturers. As a result, most shoe manufactures lose an unknown number of potential footwear sales each year, simply because customers cannot physically try on a desired model of footwear before purchase. Moreover, many of those customers who do purchase footwear remotely receive footwear that does not properly fit, and are dissatisfied with their purchases.
BRIEF SUMMARY OF THE INVENTION
[0005] Advantageously, the present invention provides a method whereby a customer may purchase footwear through a remote communication channel, and be assured that the purchased footwear will properly fit upon delivery. According to the invention, a customer purchases footwear by specifying the last that is used to construct the footwear. A customer may identify a particular last based upon careful measurement of the customer's feet. A customer may also identify a last based upon previous experience with footwear that was constructed using the last.
[0006] A customer may directly specify a last according to, for example, a last model number alone or a last model number in combination with a particular last size. Alternately, or additionally, the shoe provider may employ a data structure to correlate a customer's identity with one or more particular lasts that provide properly fitting shoes for the customer. The customer can then inherently select a particular last used to construct the footwear by providing his or her identity when ordering the model of desired footwear. By explicitly or inherently designating the last from which the footwear is constructed, the customer can ensure that the footwear is constructed to properly fit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 illustrates a shoe distribution center for providing shoes to a plurality of customers according to one embodiment of the invention.
[0008] FIG. 2 shows a method for providing custom-fitted shoes according to one embodiment of the invention.
[0009] FIGS. 3A-3C illustrate information contained in orders for custom-fitted shoes according to various embodiments of the invention.
[0010] FIG. 4 illustrates a shoe distribution center for providing shoes to a plurality of customers according to another embodiment of the invention.
[0011] FIG. 5 shows a customer/last database according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0012] FIG. 1 illustrates a shoe distribution center 101 for providing shoes to a plurality of customers 103 . As seen in this figure, the customers 103 can communicate with the distribution center 101 using one or more of a variety of remote communication channels, so that the customers 103 do not have to be physically present at the distribution center 101 . Customer 103 A, for example, may order shoes from the distribution center 101 by a parcel service 105 , such as the U.S. Postal Service, United Parcel Service (UPS), Federal Express, or any other suitable parcel service. Customer 103 B may submit an order for footwear to the distribution center 101 using a telephone service 107 . As will be appreciated by those of ordinary skill in the art, the telephone service may be an ordinary PSTN telephone service, a wireless telephone service, or any combination thereof. Further, the customer 103 B may submit the order using voice instructions (either to a person or to a recording device), or transmit written ordering instructions using a facsimile machine.
[0013] Some customers, such as customer 103 C, may order footwear from the distribution center 101 via an electronic communication network 109 . Perhaps the most well known example of such an electronic communication network 109 that may be used to order footwear from the distribution center 101 is the Internet, but those of ordinary skill in the art will appreciate that other network arrangements, such as intranets, local area networks, or other types of wide area networks may also be employed by customer 103 C to order footwear from the footwear distribution center 101 .
[0014] With this arrangement, the footwear distribution center 101 may provide the customer with one or more pages written in a markup language, such as the Hypertext Markup Language (HTML) or the Extensible Markup Language (XML) (i.e., a Website). The pages may, for example, display various footwear models currently available from the distribution center 101 , along with ordering information instructing the customer 103 C on the procedure to order footwear from the distribution center 101 . The pages may also include one or more interactive questionnaires requesting ordering information from the customer 103 C. Such information will typically include the customer's shipping address, billing information, and the footwear model desired by the customer. The questionnaires will also request the customer 103 C to directly or indirectly specify the last used to manufacture the footwear, as will be explained in detail below. Using a computer with a software program for viewing the pages (i.e., a browser), the customer 103 C can then select and order a particular model of footwear from the distribution center 101 by responding to the questionnaires over the communication network 109 .
[0015] Other customers, such as customer 103 D, may instead order footwear from the distribution center 101 through an electronic mail service 111 . Of course, those of ordinary skill in the art will appreciate that the electronic mail service 111 can be implemented using an electronic communication network 109 as described above. The electronic mail service 111 may also be implemented using, for example, a direct communication connection with the distribution center 101 through a telephone call to the distribution center using a modem.
[0016] Still other customers may use another communication channel that permits a customer to remotely order footwear from the footwear distribution center 101 . In fact, those of ordinary skill in the art will appreciate that various embodiments of the invention may be implemented using any combination of desired remote communication channels.
[0017] It will also be appreciated by those of ordinary skill in the art that the information used to order footwear may be obtained from any suitable source. As noted above, for example, a customer 103 C may view ordering information provided on HTML pages through the communications network 109 . Alternately, a customer may obtain ordering information through print advertisements, catalogs, television, or any other suitable source. The ordering information may include, for example, the footwear models available at the distribution center 101 , the color schemes available for each model, price, or other characteristics of the footwear. Further, the ordering information may include customizing information, such as names or images that are available to be custom-applied to the footwear being ordered.
[0018] Turning now to the footwear distribution center 101 , the center 101 includes a footwear order-receiving unit 113 , which receives the footwear orders from customers 103 provided through the remote communication channels, and a footwear supply unit 115 , which supplies footwear according to the customers' orders. More particularly, the footwear supply unit 115 includes a footwear inventory 117 containing one or more models of footwear in a variety of sizes, and a footwear manufacturing unit 121 . The footwear manufacturing unit 121 has a last inventory 121 containing a plurality of lasts in different sizes, and a heating unit 123 for heating the lasts to modify footwear from the footwear inventory 117 , as will be explained in detail below.
[0019] As previously noted, the footwear order-receiving unit 113 receives the footwear orders from customers 103 . The order-receiving unit 113 may include a number of different components, depending upon the remote communication channels supported by the distribution center 101 . For example, if the distribution center 101 communicates with customers 103 through an electronic communication network 109 (such as the Internet), then the receiving unit 113 may be include fully automated components for processing a customer's order. These components of the receiving unit 113 may be embodied, for example, by a server computer that receives footwear orders from the customer 103 C and relays those orders on to the footwear supply unit 115 . Similarly, if the footwear distribution center 101 supports remote communication with customers 103 through a telephone service 107 , the order receiving unit 113 may include a fully automated voice menu system that allows customer 103 B to order footwear using a telephone handset keypad or voice instructions in response to a series of audible prompts. If the operation of the footwear supply unit 115 is fully automated, then the customer 113 may order footwear without human intervention.
[0020] If the distribution center 101 supports communication channels that require a human interpretation of messages, then the order-receiving unit 113 will include human personnel. For example, with some embodiments of the footwear distribution center 101 , the order-receiving unit 113 includes an operator to receive and understand voice instructions from a customer 103 B over the telephone system 107 . If the distribution center 101 receives written communications from customers 103 via a parcel system 105 or electronic mail system 111 , then the order receiving unit 113 will include human readers to read and interpret footwear orders conveyed in the mail messages from the customers 103 .
[0021] Referring back to the footwear supply unit 115 , the footwear inventory 117 contains at least one model of footwear in a variety of sizes. As is known in the art, each pair of footwear is formed using a last, which defines the shape of the footwear. Additionally, the interior of each pair of footwear incorporates a moldable fit-component that allows each shoe to be remolded to lengths and widths differing from its original length and width. The last inventory 121 then includes a number of heatable lasts or mold cores that can be used to remold the length and width of the footwear in footwear inventory 117 to the length and width of the heatable last. In this manner, the shape of each piece of footwear in the footwear supply unit 115 can be resized using a last from the last inventory 121 .
[0022] Preferably, the footwear inventory 117 includes the model of footwear in intermediate size increments. The last inventory 121 then includes lasts for molding footwear to length and width sizes that are not represented in the inventory 117 . With one embodiment of the invention, for example, the footwear inventory 117 includes at least one style of stock shoes in relatively small size increments (e.g., standard half sizes) over a wide range of lengths. Thus, the stock shoes may range from length size 6 to size 14, and in full size increments for length sizes between 14 and 20. The stock shoes all have the same width (e.g., size “C”), or have one or more different widths for each length. The last inventory 121 then includes lasts for each desired length and width size increment (e.g., each ¼ length size increment for lengths ranging from size 6 to 13½ and each ½ length size increment for lengths ranging from size 13½ to 20, and each width increment for width sizes D, E and EE). The features and operation of such a footwear supply unit 115 are described in more detail in U.S. Pat. Nos. 5,714,098 and 5,879,725 to Daniel R. Potter, which were incorporated entirely herein by reference above.
[0023] With this arrangement, the footwear supply unit 115 can thus produce footwear in a variety of desired sizes by using a specific last size. For example, with the above embodiment, if a customer ordered a particular model of shoes with a length of size 8½ and a width of size “C,” the footwear inventory 117 already includes footwear manufactured with a last of that shape. Thus, the footwear supply unit 115 could supply the ordered shoes directly out of the footwear inventory 117 . On the other hand, if a customer ordered a particular model of shoes with a length of size 8¼ and a width of size “E,” the footwear supply unit 115 could supply the shoes by reforming stock shoes (from the footwear inventory 117 ) with a last of size 8¼ and a width of size “E” (from the last inventory 121 ).
[0024] With some embodiments of the invention, the lasts in the last inventory 121 have the same overall shape as the lasts used to make the stock shoes in the footwear inventory 117 . By using the same last (that is, the same last shape) to both initially construct shoes in the footwear inventory 117 and subsequently modify these shoes, a customer may easily determine a properly fitting shoe size for a particular model of shoe. For example, a customer may know that, with a last of shape A, a properly fitting shoe will have a length of size 8¼ and a width of size “E,” whereas, with a last of shape B, a properly fitting shoe will a length of size 8½ and a width of size “C.” If the lasts in the last inventory 121 and the lasts used to make the stock shoes in the footwear inventory 117 both include lasts of the same shape (for example, lasts of shape B), by specifying a particular last (that is, by specifying a last of a particular shape and size), a customer can confidently order custom-fitted footwear that will fit properly. Thus, with the above example, the customer will know that, when ordering a shoe constructed with the last of shape B, to order footwear with a length of size 8½ and a width of size “C,” rather than a length of size 8¼ and a width of size “E.”
[0025] Of course, other embodiments of the invention may employ differently shaped lasts to construct the footwear in footwear inventory 117 than are stored in last inventory 121 . With these embodiments, the footwear inventor 117 , may, for example, keep a greater number of lasts with smaller size increments in the last inventory 121 than the previously described embodiments. Thus, the last inventory 121 may include lasts for each ¼ size increment from size 6 to 13½ and each ½ length size increment for lengths ranging from size 13½ to 20, and each width increment for width sizes D, E and EE. With these embodiments, if a customer orders a shoe manufactured with a particular last, the footwear supply unit 115 will be able to modify a stock shoe from the footwear inventory 117 with the desired last from the last inventor 121 , even if the stock shoe had originally been manufactured with a differently shaped last.
[0026] With some embodiments of the invention, the footwear supply unit 115 may include footwear constructed with differently shaped lasts, while the last inventory 121 may include a variety of differently shaped lasts. For these embodiments, a last identifier can be used to uniquely identify each last employed to manufacture each item of footwear in the footwear inventory 117 . The last identifier can also be used to uniquely identify each last in the last inventory 121 . With this arrangement, a last identifier will identify a particular last by its overall shape, length, width, and any other relevant size information. Identifying each last with a unique last identifier allows a customer 103 to order footwear constructed with a specific last that will ensure that the footwear will fit properly. For example, the customer may specify that a particular last from the last inventory 121 to be used to reform the size of a shoe in the footwear inventory 117 . Alternately, the customer may order existing footwear from the footwear inventory 117 based upon the last that was used to manufacture the footwear.
[0027] A variety of different formats may be employed for the last identifier. For example, the last identifier may be a single alphanumeric value that uniquely identifies a last. Thus, the number “128.255” may identify a last of a particular shape indicated by the number “12,” having a length of size 8¼, and a width of size “E” (the fifth letter in the alphabet). Alternately, the last identifier may be made up of a number of discrete portions, each corresponding to a particular characteristic of a last. Thus, the same last discussed in the previous example may be identified by the last identifier “Last 12, length 8¼, width E.”
[0028] Still further, if the same last shape is used to manufacture every size of a particular model of footwear, then that model of footwear can be used to inherently identify the last shape as part of the last identifier. For example, if every size of a footwear model “Air Potter” is originally constructed or reformed with the last of the particular shape indicated in the previous examples by the number “12,” then the last identifier may be “Air Potter, length 8½ width E.” Of course, those of ordinary skill in the art will appreciate that still other formats can be used to uniquely identify a last.
[0029] The operation of the distribution center 101 will now be described with reference to the method illustrated in FIG. 2 . First, in step 201 , the order-receiving unit 113 receives an order 301 for footwear from a customer 103 . As noted above, the order 301 may be received using any remote communication channel supported by the distribution center 101 , including channels using a parcel system 105 , a telephone system 107 , an electronic communication network 109 (for example, the Internet), an electronic mail system 111 , or any other suitable remote communication channel.
[0030] With some embodiments of the invention, the order 301 includes the ordering information shown in FIG. 3A . More particularly, the footwear order 301 includes a footwear model selection 303 , designating the particular model of footwear from the footwear inventory 117 desired by the customer 103 . The footwear model selection 303 may include, for example, the model type and a desired color scheme. The order 301 also includes a last identifier 305 to uniquely identify the last by which the customer 103 wishes to have the ordered shoes manufactured. The last identifier 305 identifies both the last shape and the last size, as noted above. Still further, the order may contain additional relevant information, such as, for example, a name, initials or an image to be custom-applied to the ordered footwear.
[0031] As also previously noted, with other embodiments of the invention the footwear model may inherently identify a single last shape. With these embodiments, the order 301 will include footwear model and size information, as shown in FIG. 3B . That is, the order 301 will include the footwear model selection 303 , length size information 307 , and width size information 309 . This information together defines the particular last size and shape used to construct the ordered footwear.
[0032] In step 203 , the distribution center 101 determines if the footwear inventory 117 includes the footwear specified in the order 301 . More particularly, the distribution center 101 determines if the footwear inventory 117 contains footwear that has already been manufactured with the last specified in the order 301 . It should be noted that this determination may be made by the order-receiving unit 117 upon receiving an order 301 from a customer 103 , or by the footwear supply unit 115 after receiving a customer's order 301 relayed by the order-receiving unit 117 .
[0033] If the footwear is in the footwear inventory 117 , then the distribution center 101 provides the footwear to the customer 103 directly from the footwear inventory 117 in step 207 . If the footwear specified in the order 301 is not a size carried in the footwear inventory 117 , then, in step 205 , the footwear is manufactured in the footwear supply unit 115 using the last identified in the order 301 . That is, the last specified in the order 301 is selected from the last inventory 121 , and used to modify the size of footwear already included in the footwear inventory 117 . As noted above, this operation is discussed in detail in U.S. Pat. Nos. 5,714,098 and 5,879,725 to Daniel R. Potter, which were incorporated entirely herein by reference above. Once the footwear has been remolded to comply with the customer's order, then the distribution center 101 provides the footwear to the customer 103 in step 207 .
[0034] It should be noted that the distribution center 101 can provide the ordered footwear to the customer 103 in step 207 using any suitable shipping method. For example, the distribution center 101 can mail the custom-fitted footwear directly to an address provided by the customer through a parcel service, such as the U.S. Postal Service, Federal Express, or United Parcel Service. Alternately, the distribution center 101 can ship the ordered footwear to a retail store, such as a store associated with the shoes' manufacturer. The customer 103 can then pick up the ordered footwear in person from retail store. The customer 103 may select the appropriate retail store from a list of available retail stores, or may simply allow the distribution center 101 to determine the closest retail store to the customer. Of course, still other techniques for shipping the ordered footwear to the customer will be apparent to those of ordinary skill in the art.
[0035] By using the distribution center 101 described above, a customer 103 need only identify a particular last that the customer knows will provide properly fitting footwear to confidently obtain custom-fitted footwear. As will be appreciated by those of ordinary skill in the art, a customer can determine which particular last or lasts that will provide properly fitting footwear in a variety of ways. A customer 103 may, for example, initially try on a variety of footwear to identify a particular last that, when used to manufacture a shoe, offers the best fit for the customer. After trying on a variety of footwear once to determine a suitable last, the customer need not try on footwear again, but may instead simply order footwear made with the particular last. Alternately, the customer 103 may employ a measurement process, such as a digital scan of the customer's feet, to determine an appropriate last that will provide the customer with properly fitting shoes. Regardless of the method of identifying the lasts that will provide custom-fitting footwear, once the customer 103 has identified the lasts, the customer 103 can employ the distribution center 101 to order footwear by referring to that last.
[0036] Yet another embodiment of the invention is illustrated in FIG. 4 . In this figure, the distribution center 101 includes a customer/last database 125 . As shown in FIG. 5 , this customer/last database 125 includes a table associating each customer 103 with at least one last that will provide the customer with custom fitting shoes. For example, in the table, the customer 103 A is associated with the last specified by the last identifier 128.255. Thus, the database 125 contains one or more records, with each record having a customer field identifying a customer and at least one last field identifying a last that will provide the customer with custom fitting footwear. With the customer/last database 125 , the customer can omit providing a last identifier when ordering footwear. Instead, the customer need only identify himself or herself. The distribution center 101 can then use the customer/last database 125 to identify a particular last that will provide custom-fitted footwear for that customer, and manufacture the ordered footwear using the last corresponding to the customer. Thus, with this embodiment, the customer's order 301 may include only the footwear model selection 303 and the customer identification 311 as shown in FIG. 3C . As will be appreciated by those of ordinary skill in the art, the customer/last database 125 may be implemented using a software database, a written or printed table, or any other suitable medium for storing customer identity and last information.
[0037] In addition to storing customer identity and last information, the customer/last database 125 may also store any other type of information that may be useful to the customer or a shoe manufacturer associated with the distribution center 101 . For example, for customers who are growing children, the customer/last database 125 may further store the age of the customer. This will allow the shoe manufacturer associated with the distribution center 101 to compile information for foot morphology studies regarding growth patterns, sizing information for specific age groups, and other footwear related projects.
[0038] Of course, those of ordinary skill in the art will appreciate that more than one last can provide a customer with custom-fitting footwear. Thus, with some embodiments of the invention, a customer may identify two or more lasts that will provide him or her with properly fitting footwear. The customer/last database 125 can then associate each last with that customer, and the distribution center 101 can determine which last to use when manufacturing shoes for the customer. For example, the customer may identify a first last that provides the customer properly fitting footwear when used to construct (or remold) hiking boots, and another, second last that provides the customer with properly fitting footwear when used to construct (or remold) basketball shoes. If the customer orders basketball shoes, the distribution center 101 will determine that the shoes should be remolded using the second last rather than the first last. Alternately, the customer can specify which of the suitable lasts should be used to construct or remold ordered footwear.
[0039] In addition, those of ordinary skill in the art will appreciate that a customer 103 can specify different lasts for the left and right shoes in a pair of footwear. For example, a customer may find that a shoe manufactured with a particular shape or size of last best fits his or her left foot, while a shoe manufactured with another shape or size of last best fits his or her right foot. Accordingly, various embodiments of the invention may allow a customer 103 to order footwear manufactured with different lasts used to manufacture the left and right shoes. Still further, with various embodiments of the invention, the customer/last database 125 can associate different lasts with a customer's left and right feet.
[0040] While the invention has been described with respect to specific examples including presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above described systems and techniques that fall within the spirit and scope of the invention as set forth in the appended claims. | A method whereby a customer may purchase footwear through a remote communication channel, and be assured that the purchased footwear will properly fit upon delivery. The customer purchases footwear by designating the last that is used to construct the footwear. A customer may identify a particular last based upon careful measurement of the customer's feet. A customer may also identify a last based upon previous experience with footwear constructed using the last. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a belt unit of an electrophotographic printing apparatus.
[0003] 2. Background Art
[0004] Here will be described a belt unit, especially a belt photoconductor unit in an electrophotographic printing apparatus according to the related art.
[0005] As a general configuration of a belt photoconductor unit, there is known a configuration in which a drive roller for rotating a belt photoconductor and a tension roller having tension urged by springs or the like are provided between two frames for supporting the rollers and in which the belt photoconductor is wound around the rollers.
[0006] The belt photoconductor unit is configured so that a sensor for detecting a widthwise end of the belt photoconductor is provided on one of the frames or the like in order to perform detection of misalignment during rotation, detection of a seam of the belt photoconductor, and so on.
[0007] The belt photoconductor needs to be exchanged for a new one periodically since it is an expendable article. At the time of exchange, it is necessary to remove the belt photoconductor from the frames and mount a new one. In the related art, it was necessary to shift the tension roller in a direction of narrowing the distance between the drive roller and the tension roller before removal/mounting of the belt photoconductor.
[0008] Further, at the time of mounting of the belt photoconductor, the belt photoconductor must be mounted so as to be positioned in a groove of the sensor properly. This work was very difficult. As a related-art technique for setting the belt photoconductor in a proper position, there is known a technique in which: a first cam and a second cam for moving the tension roller in a direction of relaxing the belt photoconductor are provided on opposite ends of a rotating shaft; the length of the first cam is set to be larger than the length of the second cam; slowly increasing tension is applied to the belt photoconductor to thereby mount the belt photoconductor in the groove of the hole sensor (e.g., see JP-A-5-019667 (page 3 and FIG. 3)).
[0009] According to the related art, it was structurally difficult to make the length difference between the first and second cams extremely large. For this reason, when a belt photoconductor having a large circumferential length was used, there was the possibility that the belt photoconductor would be scratched so as to be disabled from being used because slackness of the belt photoconductor could not be eliminated reliably to make it impossible to mount the belt photoconductor in the groove of the sensor accurately.
[0010] Furthermore, the mounting position of the belt photoconductor was indefinite in the widthwise direction. For this reason, there was the possibility that the belt photoconductor could not exhibit its original performance because the belt photoconductor might be mounted in a position different from the original position where the belt photoconductor should be used. In addition, there was the possibility that the belt photoconductor would be damaged so as to be disabled from being used because the belt photoconductor might come into contact with the sensor.
[0011] There was possibility that the belt photoconductor might be inserted into the electrophotographic printing apparatus body while the cams were not restored to their positions at the time of actual printing, that is, to the positions where tension would be applied to the belt photoconductor after the belt photoconductor was mounted. For this reason, there was the possibility that the belt photoconductor was scratched so as to be disabled from being used.
SUMMARY OF THE INVENTION
[0012] It is an object of the invention to provide a belt photoconductor unit with a simple configuration that allows a belt to be mounted in a position where a sensor can detect the belt properly without damaging the belt.
[0013] To achieve the object, the invention provides a belt unit of an electrophotographic printing apparatus, including: two rollers for supporting a belt so as to be substantially in parallel with each other; two frames for supporting the rollers and attached to opposite ends of one of the rollers respectively so as to be perpendicular to the rollers; two support members attached to opposite ends of the other roller so as to be perpendicular to the rollers; two elastic members interposed between the two support members and the two frames respectively; and a belt mounting guide provided between the two frames; wherein the belt mounting guide includes a rotating shaft disposed in parallel with the rollers, and an edge portion inclined relative to an axial direction of the rotating shaft.
[0014] Preferably, a step portion is provided at one end of the edge portion of the belt mounting guide and in a position where the belt travels normally.
[0015] Preferably, when the belt is mounted, the belt mounting guide is located to be higher than a frame that forms a slot portion included in an apparatus body in which the belt unit is mounted.
[0016] Preferably, the rotating shaft of the belt mounting guide is provided with a blade for cleaning a back surface of the belt.
[0017] The invention provides an electrophotographic printing apparatus, including: an apparatus body; and a belt unit installed in the apparatus body; wherein the belt unit includes: a belt, two rollers for supporting the belt so as to be substantially in parallel with each other, two frames for supporting the rollers and attached to opposite ends of one of the rollers respectively so as to be perpendicular to the rollers, two support members attached to opposite ends of the other roller so as to be perpendicular to the rollers, two elastic members interposed between the two support members and the two frames respectively, and a belt mounting guide provided between the two frames; and the belt mounting guide includes a rotating shaft disposed in parallel with the rollers, and an edge portion inclined relative to an axial direction of the rotating shaft.
[0018] Preferably, the apparatus body includes a frame that forms a slot portion in which the belt unit is installed; and, when the belt is mounted, the belt mounting guide is located to be higher than the frame.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The present invention may be more readily described with reference to the accompanying drawings:
[0020] [0020]FIG. 1 is a schematic view of a belt mounting mechanism according to the invention.
[0021] [0021]FIG. 2 is a schematic view of the belt mounting mechanism according to the invention at the time of traveling of a belt after mounting of the belt.
[0022] [0022]FIG. 3 is a schematic configuration diagram of an electrophotographic printing apparatus to which the invention is applied.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] An embodiment of the invention will be described below. Although this embodiment will be described on the case in which a belt photoconductor is used, the invention is not limited to the belt photoconductor but may be applied to an intermediate transfer belt, a transfer belt, a fixing belt, etc.
[0024] [0024]FIG. 1 is a schematic view of a belt photoconductor unit 110 according to an embodiment of the invention at a point of time when a belt photoconductor used in the belt photoconductor unit 110 is mounted in an electrophotographic printing apparatus.
[0025] The belt photoconductor unit 110 according to the embodiment of the invention includes: a belt photoconductor 1 which is a detachably mountable photoconductor shaped like a belt; frames 2 a and 2 b ; a drive roller 3 for driving the belt photoconductor 1 to rotate; a tension roller 4 for adjusting tension acting on the belt photoconductor 1 ; and support members 5 for connecting the tension roller 4 to the frames 2 a and 2 b . The belt photoconductor unit 110 further includes: a first rotating shaft 6 disposed between the frames 2 a and 2 b ; cams 7 and a first lever 8 connected to opposite ends of the first rotating shaft 6 ; springs 9 for applying tension to the tension roller 4 in a direction of moving away from the driver roller 3 ; and guide shafts 10 for guiding the respective springs 9 .
[0026] While one of the support members 5 , one of the cams 7 , one of the springs 9 and one of the guide shafts 10 are attached to the frame 2 a , the other support member 5 , the other cam 7 , the other spring 9 and the other guide shaft 10 are attached to the frame 2 b in the same manner. The tension roller 4 is therefore supported by the support members 5 , the cams 7 , the springs 9 and the guide shafts 10 .
[0027] When the first lever 8 is rotated, the cams 7 can be also rotated to move the tension roller 4 and the support members 5 in a direction of tensing or relaxing the belt photoconductor 1 (an axial direction of each guide shaft 10 ). Each cam 7 used herein is an eccentric cam.
[0028] The guide 12 is formed so that its height varies in the widthwise direction of the belt photoconductor 1 , that is, the height of the guide 12 increases slowly as the belt photoconductor 1 is mounted more deeply. When second lever 13 is rotated, the guide 12 is also rotated so as to go out or come in.
[0029] For example, the sensor 14 is a transmission type sensor which detects meandering of the belt photoconductor 1 when printing is actually performed. The sensor 14 is disposed so that one widthwise end portion of the belt photoconductor 1 faces a U-shaped groove of the sensor 14 . Although the description of how to correct meandering will be omitted here, for example, the method described in JP-A-2002-296972 may be used, which is incorporated by reference. In this embodiment, as shown in FIG. 1, the sensor is attached to a position opposite to an end of the lower part of the belt when the belt photoconductor is mounted.
[0030] The operation of mounting the belt photoconductor will be described below with reference to FIG. 1.
[0031] When the belt photoconductor 1 is mounted, the belt photoconductor 1 is horizontally pulled out from the electrophotographic printing apparatus body not shown, and the first lever 8 is rotated in the direction of relaxing the tension roller 4 as shown in FIG. 1 to thereby mount the belt photoconductor 1 . At the same time, the second lever 13 is also rotated to locate the guide 12 in the position shown in FIG. 1.
[0032] The guide 12 has a rotating shaft, and an edge portion inclined relative to the shaft.
[0033] Because of the shape of the guide 12 , the height of the guide 12 increases slowly in the direction of tensing the belt photoconductor 1 as the belt photoconductor 1 is mounted more deeply. As a result, slackness of the lower part of the belt photoconductor 1 is eliminated, so that the belt photoconductor 1 is mounted in the groove of the sensor 14 firmly.
[0034] A step portion 12 a (see FIG. 2) is provided at an end of the guide 12 . The end of the belt photoconductor 1 abuts on the step portion 12 a at the end of the guide 12 as the belt photoconductor 1 is mounted deeply. As a result, the belt photoconductor 1 is aligned with a line along which the belt photoconductor 1 will travel at the time of actual printing.
[0035] At the time of mounting of the belt photoconductor, the guide 12 needs to be located in a position (see FIG. 1) protruded upward of the frames 2 a and 2 b from its normal position used at the time of actual printing. Therefore, at the time of mounting of the belt photoconductor, the guide 12 is configured so as be higher than a frame 24 that forms each slot portion of the apparatus body 100 (See FIG. 3). In this manner, the guide 12 has a miss-insertion preventing function which prevents the belt from being inserted into the electrophotographic printing apparatus body by mistake in the condition that the belt has not completely mounted yet.
[0036] [0036]FIG. 2 shows a schematic view of the belt photoconductor unit 110 at the time of actual printing.
[0037] In FIG. 2, at the time of actual printing, the first lever 8 is rotated to make the tension roller 4 tense the belt photoconductor 1 whereas the second lever 13 is rotated to the position shown in FIG. 2 to prevent the guide 12 from coming into contact with the belt photoconductor 1 .
[0038] On this occasion, a blade 15 attached to the second rotating shaft 11 is located in a position where the blade 15 comes into contact with a back surface of the belt photoconductor 1 . As a result, the blade 15 cleans the back surface of the belt photoconductor 1 . The back surface of the belt photoconductor 1 is smeared, for example, with toner scattered at the time of actual printing but can be cleaned by the blade 15 .
[0039] An overall configuration of an electrophotographic printing apparatus using belt photoconductors as shown in FIG. 1 will be described below with reference to FIG. 3.
[0040] An imaging unit 16 a includes a belt photoconductor 17 a , a charger 18 a , an exposure device 19 a , a development device 20 a , a transfer device 21 a , and a cleaning device 22 a . Each of imaging units 16 b , 16 c , and 16 d has the same configuration as that of the imaging unit 16 a.
[0041] The imaging units 16 a , 16 b , 16 c , and 16 d are used for printing different colors on a sheet of paper 23 . For example, the imaging unit 16 a is used for printing yellow, the imaging unit 16 b for printing magenta, the imaging unit 16 c for printing cyan, and the imaging unit 16 d for printing black.
[0042] The printing operation of the imaging unit 16 a will be described below.
[0043] The belt photoconductor 17 a starts rotating on the basis of a printing operation start signal given from a controller not shown. The belt photoconductor 17 a rotates at a speed equivalent to the printing speed of the electrophotographic printing apparatus so that the rotation of the belt photoconductor 17 a continues until the printing operation is completed. When the belt photoconductor 17 a starts rotating, a high voltage is applied to the charger 18 a so that a surface of the belt photoconductor 17 a is evenly charged, for example, with positive charges.
[0044] When character/graphic data converted into dot images are transmitted from the controller not shown to the electrophotographic printing apparatus so that the dot images serve as on/off signals for the exposure device 19 a , regions irradiated with laser light emitted from the exposure device 19 a and regions not irradiated with the laser light are formed in the surface of the belt photoconductor 17 a . Whenever a portion of the belt photoconductor 17 a which have been destaticized by the irradiation with the laser light emitted from the exposure device 19 a reach a position facing the development device 20 a , this portion of the belt photoconductor 17 a attracts positively charged toner by static electricity. In this manner, atoner image is formed on the belt photoconductor 17 a . The sheet of paper 23 is transported in synchronism with the timing at which the print data formed on the belt photoconductor 17 a reach a transfer position. The toner image formed on the belt photoconductor 17 a is attracted onto the sheet of paper 23 by the transfer device 21 a 's function of charging the back surface of the sheet of paper 23 with charges reverse in polarity to the toner image. Incidentally, after passing through the transfer position, the belt photoconductor 17 a is cleaned by the cleaning device 22 a and any residual toner on the belt photoconductor 17 a is sucked in by a suction blower not shown and collected into a collecting portion not shown, in order to be ready for the next printing operation.
[0045] After passing through the imaging unit 16 a , the sheet of paper 23 is subjected to similar printing operations at the imaging units 16 b , 16 c , and 16 d successively and then transported to a fixing device not shown. The toner image on the sheet of paper 23 that has arrived at the fixing device is melted and fixed on the sheet of paper 23 .
[0046] Each of the belt photoconductors 17 a , 17 b , 17 c and 17 d needs to be exchanged for a new one periodically, since the belt photoconductors 17 a , 17 b , 17 c and 17 d deteriorate while printing operations are repeated.
[0047] The use of the belt mounting mechanism in the invention makes it possible to reduce slackness of the belt more reliably than in the related art. Accordingly, an operator can mount the belt in the sensor easily. As a result, it is possible to prevent the belt photoconductor from being damaged and disabled before start of a printing operation.
[0048] In addition, the belt mounting guide shares the same rotating shaft with the blade for cleaning the back surface of the belt. Accordingly, the blade can be installed reliably to ensure the cleaning of the belt photoconductor during actual printing.
[0049] As described above, the invention makes it possible to mount a belt in a sensor easily without damaging the belt in spite of a simple configuration. In addition, a blade can be mounted reliably to allow a back surface of the belt to be cleaned during actual printing. | A belt unit of an electrophotographic printing apparatus, includes: two rollers for supporting a belt so as to be substantially in parallel with each other; two frames for supporting the rollers and attached to opposite ends of one of the rollers respectively so as to be perpendicular to the rollers; two support members attached to opposite ends of the other roller so as to be perpendicular to the rollers; two elastic members interposed between the two support members and the two frames respectively; and a belt mounting guide provided between the two frames. The belt mounting guide includes a rotating shaft disposed in parallel with the rollers, and an edge portion inclined relative to an axial direction of the rotating shaft. | 6 |
REFERENCE TO PRIOR APPLICATIONS
This is a continuation of application Ser. No. 08/123,775, filed 09/20/93 and now abandoned which is a continuation-in-part of the instant assignee's U.S. application Ser. No. 07/944,610, now U.S. Pat. No. 5,298,347 entitled Battery Pack, filed on Sep. 14, 1992 by Adnan Aksoy and Mark S. Bresin as common inventors of the present invention. Applicants claim priority of invention under 35 USC Section 120.
FIELD OF THE INVENTION
This invention relates generally to battery cell packs, and more specifically to battery pack construction.
BACKGROUND
Battery packs for portable devices such as two-way radios typically comprise a number of cells having contacts welded together all within a housing. The individual cells are interconnected using sheet metal tabs which are spot welded to the cell terminals. Usually, the interconnected cells are then spot welded to a flex circuit and subsequently inserted into a battery housing. This method of manufacture is wrought with inefficient assembly procedures and unnecessary parts and labor resulting in excessive manufacturing expense and compromised reliability.
Consumer loaded batteries for consumer electronics such as cameras, radios, CD players, etc., typically have spring loaded contacts on one end and metal contacts coupled to the opposite end of the primary cells. Consumer loaded battery packs do not require the extra circuitry typically found in battery packs. Battery packs for portable radios will usually include resistors, thermistors, diodes and other components that enable the battery packs to be rechargeable and/or intrinsically safe. Thus, consumer loaded battery compartments may only have stamped metal on the housing and electrical loss between battery cells and circuitry is of little concern in these applications.
Other battery packs, which are either consumer loaded or loaded and sealed by the manufacturer typically comprise a number of cells that are shrink wrapped together or packaged in a plastic housing. Again, many of these cells are typically coupled together electronically by welding steel tabs to unlike terminals (positive and negative) on separate cells. Subsequently, the welded cells are shrink wrapped together and inserted into a housing. Again, this assembly procedure is inefficient, resulting in excessive labor and manufacturing costs.
The drive to reduce weight in electronic consumer products is now impacting battery pack assembly as much as the drive to increase the ease of assembly or manufacturability of battery packs. Therefore, the ability to integrate features in less components and parts is critical in reducing the number of assembling steps. Therefore, a need exists for a battery pack that provides the convenience of consumer loaded battery packs, provides for a reduction in weight, and allows for greater efficiency and reduced cost in assembly and manufacture.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a battery pack.
FIG. 2 is a perspective view of a battery pack according to a first embodiment of the present invention.
FIG. 3 is a perspective view of a battery pack according to a second embodiment of the present invention.
FIG. 4 is a perspective view of a battery pack according to a third embodiment of the present invention.
FIG. 5 is an exploded view of wall 310 taken at lines A--A in FIG. 4.
FIG. 6 is an exploded view of a first embodiment of an attachment mechanism according to the present invention.
FIG. 7 is an exploded view of a second embodiment of an attachment mechanism according to the present invention.
FIG. 8 is an exploded view of a third embodiment of an attachment mechanism according to the present invention.
FIG. 9 is a perspective view of a battery pack according to a fourth embodiment of the present invention.
FIG. 10 is an exploded view of an alignment mechanism according to the present invention.
FIG. 11 is a cross-sectional view of the battery pack taken at lines B--B of FIG. 9.
FIG. 12 is an alternate embodiment of the cross-sectional view of FIG. 11.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A battery pack comprises a first housing member having an integrated latch feature, a header frame detachably mounted to the first housing member, a plurality of cells for insertion into the header frame and first housing member, circuitry on the header for coupling the plurality of cells and providing charger and power contacts, and a second housing member being substantially laminar and being adhesively attached to said first housing member.
Referring to FIG. 1, there is shown a perspective view of a battery pack 10 discussed in U.S. patent application Ser. No. 07/848465 entitled Weldless Battery Pack, filed on Mar. 9, 1992 by Mark S. Bresin, assigned to the present assignee, Motorola, Inc. and hereby incorporated by reference. The battery pack 10 comprises a housing having a top portion 2 and a bottom portion 4. The housing portions are preferably constructed to snap together. Alternatively, the housing portions could be ultrasonically welded together. The top housing member 2 also includes a latch feature 3 that mates with a recessed area 5 in the bottom portion 4 to allow the detachable coupling of the battery pack 10 to a radio (not shown). Within the housing portions 2 and 4, lies a header frame 11 (for holding cells 12) being detachably mounted into at least one of the housing portions.
Referring to FIG. 2, there is shown a perspective view of a battery pack 100 in accordance with the present invention. The battery pack 100 preferably comprises a first housing member 104 having a latch feature 103 incorporated or integrated into the first housing member 104. Next, a header frame 111 is mounted into the first housing member 104. The header frame is preferably snapped into the first housing member via the groove 150 in the header and the mating railing 152 within the housing member 104. Alternatively, the header frame 111 could be integrated as part of the first housing member 104 as well. Another option is to ultrasonically weld the header frame 111 to the first housing member 104. Battery cells 112 having positive and negative terminals 114 and 113 respectively are then oriented and inserted into the header frame 111. Circuitry means preferably including resistors (not shown), polyswitches (30), and thermistors (40) are mounted on the header frame 111 to provide charging and power contacts and the appropriate circuitry for safely charging rechargeable battery packs as is known in the art. Alternatively, the circuitry means could comprise a flex circuit having some of the components such as the resistors, polyswitches and thermistors, which further interconnects the cells. Finally, a second housing member 102 is preferably adhesively attached to the first housing member. In order to maximize the reduction in weight, the second housing member 102 is preferably a laminar piece of plastic such as polycarbonate having adhesive on it's interior surface for adhering to the first housing member 104. Alternatively, the second housing member 102 could be ultrasonically welded to the first housing member 104. Additionally, the second housing member 102 could serve as a label for the battery 100.
Referring to FIG. 3, there is shown an alternative battery pack 200 in accordance with the present invention. The pack 200 comprises a first housing 202 preferably having snap features 204 integrally formed in the first housing. A plurality of cells 206, preferably pre-packaged into a cell pack is placed and retained within the snap features 204. The cell pack also preferably includes a flex circuit 212 providing further interconnection between cells, contacts and other required components such as resistors and thermistors (not shown). Finally a second housing member 220 is placed on top of the cell pack 206 and snaps to the first housing member 202. The Second housing member preferably has openings 21 4 for retention by the snap features 204. Additionally, openings 216 are formed in the second housing member allowing for contact points when contacts shown on the flex 21 2 are inserted within the openings 216. Likewise, the first housing member 202 has openings 205 allowing for the insertion of contact points shown on the flex 21 2. Optionally, further integrity can be provided to the battery pack 200 by using double sided adhesive (208) (such as tape) between the inner potion of the first housing and the bottom of the cell package 206 and using double sided adhesive (207) between the inner portion of the second housing 220 and the top of the cell package 210.
Referring to FIG. 4, a third embodiment of a battery pack according to the present invention is shown. The battery pack generally includes a base portion or outer casing 302 adapted to hold a battery of cells 304. It will be understood that battery 304 will include any flex strips or circuitry described in earlier embodiment. In order to maintain battery 304 within the outer casing 302, one or more layers of adhesive material 306 could be used. For example, adhesive 306 could be a glue or some form of double sided tape. An adhesive layer 306 could be used to attach the battery 304 to the outer case 302. Also, another adhesive layer 306 could be employed on top of the battery to attach an inner casing 308 to maintain battery 304 within outer casing 302.
Generally, outer casing 308 is adapted to fit over a wall 310 generally extends around the periphery of outer casing 302. Wall 310, abutment 311 and any adhesive 306 which may be used prevents battery 304 from shifting within outer casing 302. Inner casing 308 is composed of a molded thermoformed plastic material or some other suitable material. Preferably, inner casing 308 includes a label integrally formed in the thermoformed plastic. Wall 310 preferably includes an energy director 312 (shown in detail in the cross section of FIG. 5 taken at lines A--A of FIG. 4). Energy director 310 is employed in an ultrasonic bonding technique. In particular, a shoulder portion 314 of outer casing 308 can be ultrasonically bonded to energy director 312. The ultrasonic bonding can be provided along the entire wall 310 or at selected portions as needed. Any ultrasonic bonding mechanism which is well known in the art could be used.
Also, an attachment mechanism includes a plurality of tab portions 316 positioned around the base of wall 310 to attach inner casing 308 to outer casing 302. Corresponding receiving portions 318 along a foot 320 are included in outer casing 308. A variety of embodiments for latch 316/receiving portion 320 are described in detail in reference to FIGS. 6-8. Finally, an adhesive material can be positioned around foot 310 to attach inner casing 308 to outer casing 302. Any one or any combination of the adhesive bonding, ultrasonic bonding and latching can be used.
Referring to FIG. 6, an exploded view of a first embodiment of an attachment mechanism is shown. The attachment mechanism includes a tab 322 which is generally inserted into a dimple 324. The attachment mechanism of FIG. 6 could be used, for example, to maintain the position of inner casing 308 relative to outer casing 302 when ultrasonic bonding.
Referring to FIG. 7, an exploded view of a second embodiment of an attachment mechanism is shown. The attachment mechanism includes a tab portion 326 adapted to retain a notch 328 of outer casing 308. The attachment mechanism of FIG. 6 could also be used to maintain the position of inner casing 308 relative to outer casing 302 when ultrasonic bonding.
Finally, referring to FIG. 8, an exploded view of a third embodiment of an attachment mechanism is shown. The attachment mechanism includes a latch 330 adapted to positively engage a hole 332 positioned within the foot 31 8 of the outer casing 308. In particular, latch 330 includes two portions which can be compressed to engage hole 330. However, it will be understood that other types of latching mechanisms commonly known within the art could be used to positively engage the upper casing.
Turning now to FIG. 9, a perspective view of a battery pack according to a fourth embodiment of the battery pack is shown. The battery pack generally includes an outer casing 402 adapted to hold a battery of cells 404. In order to maintain battery 404 within the outer casing 402, an adhesive material 406 could be used on either side of the battery. For example, adhesive 406 could be a glue or some form of double sided tape. Finally, an inner casing 408 is included to maintain battery 404 within outer casing 402.
Unlike the embodiment of FIG. 4, the embodiment of FIG. 9 does not include a wall 310 to retain the battery from shifting within the outer casing and to provide an energy director to enable ultrasonic binding to the shoulder of the outer casing. Rather, an energy director 410 is provided along the surface of outer casing 402 to provide ultra sonic bonding to foot 412 of outer casing 408. The ultrasonic bonding can be provided along the entire energy director 410 or at selected portions.
Outer casing 402 can optionally include an alignment tab 414 to enable proper positioning of inner casing 408 relative to outer casing 402 during ultrasonic bonding. The alignment mechanism is shown in detail in FIG. 10. Foot 412 includes a notch 415 adapted to receive a tab 414. Finally, positioning guides 416 can also be selectively positioned to aid the manufacture of the battery. The alignment mechanisms 41 6 are shown in detail in the cross sections of FIGS. 11 and 12 taken at lines B--B of FIG. 9.
Turning now to FIG. 11, a cross sectional view taken at lines B--B of FIG. 9 shows the alignment of the inner casing 408 with outer casing 402 and the ultrasonic bonding at energy director 410. In particular, positioning guide 416 provides a reference point for inner casing 408. Additionally, an embankment 418 can be included to prevent the movement of foot 412 of inner casing 408 during ultrasonic bonding. That is, because the energy director is positioned along an inclined portion of outer casing 402, foot 412, which is normally horizontal, is forced into an inclined position during the ultrasonic bonding. Accordingly, embankment 418 prevents the movement of foot 412 away from positioning guide 416. Although foot 412 is shown positioned at a particular location along the outer casing 402, it will be understood that energy director 410 be positioned at any location along wall 410.
Turning to FIG. 12, an alternate embodiment incorporates a leveling surface 420 including the energy director 410. Leveling surface 420 prevents foot 412 from being forced to an inclined position during ultrasonic bonding.
In summary, the present invention reduces the complexity for manufacturing and the weight of the completed battery. In particular, a combination of ultrasonic bonding and adhesive bonding can reduce the weight and complexity of the device. A wall can contain the battery. An energy director positioned at the top of the wall to contain the cells of a battery can provide a region for ultrasonic bonding. An inner case can be positioned over the wall to seal the battery. A shoulder of the inner casing can be ultrasonically bonded to the energy director at the top of the wall. Alternatively, the wall can be replaced with an energy director positioned on the outer casing wherein a foot of the inner casing is ultrasonically bonded to the energy director. Accordingly, the present invention reduces complexity and cost compared to prior art devices. | A battery pack containing a battery of cells includes an outer casing (402) adapted to receive a battery of cells (404); a bonding surface (410) positioned along the outer casing (402); an inner casing (408) adapted to encapsulate the battery of cells (404) and having a surface for bonding to the bonding surface of the outer casing (402); and a bond provided at the bonding surface to bond the inner casing (408) to the outer casing (402). Also, a method for forming a battery pack comprises steps of positioning a battery of cells within a bonding surface of an outer casing of the battery pack; encapsulating the battery of cells with an inner casing, the inner casing having a surface corresponding to the bonding surface of the outer casing; and bonding the corresponding surface of the inner casing to the bonding surface of the outer casing. The battery pack and method for forming the battery pack reduce the weight and complexity in manufacturing. | 1 |
FIELD OF THE INVENTION
[0001] Disclosed are systems and methods related to the field of display systems, more particularly to color correction of display systems, particularly display systems using primary color sources to generate full-color images.
BACKGROUND OF THE INVENTION
[0002] Image display systems create images for human viewers to experience. The goal of such a display system is to simulate the experience of being at the location being displayed. The locations may be real, for example when a scene is recorded using a camera, imaginary, for example when a computer generates a scene using a database of shape and texture information, or a combination of real images and superimposed computer-generated images.
[0003] Regardless of the source of a particular image, the display system must be able to recreate complex color tones and intensities in order to make the recorded image appear life-like. To do this, the color spectrum of the display system must be correlated to the color spectrum of the device used to capture the image. This can be a particular challenge when displaying an image initially recorded on a continuous color media such as cinemagraphic film for display on a primary color based system such as a Cathode Ray Tube (CRT), Liquid Crystal Display (LCD), Digital Micromirror Display (“DMD”)-based display, or plasma display. For the purposes of this application, the term “continuous color” used in conjunction with terms such as image, media, display, or system will refer to the characteristic of being comprised of a continuous spectrum of light compared to the term “primary color” which will refer to the characteristic of being comprised of light from discrete primary color bands. Primary color-based image display systems, such as the ones listed above, use light sources that create a limited color space or color gamut, which can be defined by a chromaticity diagram, as is further discussed below. Commonly, a standard CRT color gamut is the benchmark for RGB signals, where positive RGB signals will define the color space that is formed by a CRT monitor according to the self-luminance properties of the phosphors used.
[0004] The perceived color of an object is determined by the wavelength of the light emitted by or reflected by the object. The human eye contains sensors, called rods and cones, that detect the light from the object focused on the retina. Rods are responsible for low light vision. Cones are responsible for color vision. There are three types of cones in the human eye, each with a distinct wavelength passband. Using outputs from the three types of cones, the human brain creates the perception of color and intensity for each portion of an image.
[0005] Continuous color media recreate the original image spectrum for each portion of the image. In the case of photographic film, this is accomplished by absorbing the unwanted portions of the spectrum of light from a source while reflecting or transmitting the portions needed to create an image. Primary color systems have a limited spectrum, or color gamut, and therefore cannot recreate the entire spectrum of the original image, but instead create the perception of the original image by stimulating the three types of cones to produce a response that approximates that would have been produced by the original spectrum. Thus, three carefully chosen light sources (red, green, and blue) can be used to provide the perception of a continuous color spectrum.
[0006] The three colors chosen to be the primary colors of a primary color display system determine the available color space of the display system. Light sources from the primary color systems have characteristics that narrow the systems' effective color gamut or color space. CRT and plasma displays will have a specific color gamut based on the light emission spectrum of the phosphors they contain, while other projection systems may have a color gamut that is defined by a filtered white light source. While a given set of primary colors may provide a very broad color space, the use of filters to select the given set of primary colors from a white light source often limits the maximum intensity the display system is capable of producing to less than a minimum acceptable amount. Further, a given selection of color filters may result in a white level, formed by combining the three primary colors, that has an undesirable color tint.
[0007] While an ideal display can create a high intensity display of very pure colors including white, real world display systems must make tradeoffs among the white level, purity of the primary colors, and the maximum available brightness. These tradeoffs further affect the secondary colors because the secondary colors are formed by combining primary colors at intensities that are set relative to the maximum intensities of those primary colors. Thus, once the primary color filters are selected, the white point and the purity of the secondary colors are also determined.
SUMMARY OF THE SYSTEM AND METHOD
[0008] Systems and methods described in this application provide for the enhanced color correction of image data with an expanded color gamut. Further disclosed is a method of correcting color image data for a pixel. A representative method comprises: providing image data for said pixel; converting the image data to a color space having a primary (P), secondary (S), and combined (W) color components; selecting a matrix corresponding to the color space; selecting a set of coefficients describing the contribution of the primary, secondary, and combined components to the output primaries; and calculating a corrected output value for each of the output primary according to the following equation:
[ R ′ G ′ B ′ ] = [ PC1 SC1 WC1 PC2 SC2 WC2 PC3 SC3 WC3 ] [ P S C ]
where:
PC1 is the contribution of the primary color component to a 1st output primary (R′); SC1 is the contribution of the secondary color component to the 1st output primary (R′); WC1 is the contribution of the combined color component to the 1st output primary (R′); PC2 is the contribution of the primary color component to a 2nd output primary (G′); SC2 is the contribution of the secondary color component to the 2nd output primary (G′); WC2 is the contribution of the combined color component to the 2nd output primary (G′); PC3 is the contribution of the primary color component to a 3rd output primary (B′); SC3 is the contribution of the secondary color component to the 3rd output primary (B′); and WC3 is the contribution of the combined color component to the 3rd output primary (B′).
[0018] The disclosed methods and systems provide independent control over the primary and secondary image colors, and the white level by allowing the correction of color image data on a pixel-by-pixel basis by using an expanded color gamut that includes negative RGB values.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a chromaticity diagram of the color space of a first display system;
[0020] FIG. 2 is a chromaticity diagram of the color space of a second display system showing shifted secondary color points and expanded color space;
[0021] FIG. 3 is a chromaticity diagram of the color space of a third display system showing the independent adjustment of the secondary color points;
[0022] FIG. 4 is a graph of three hypothetical primary color intensity data values for a single pixel showing the allocation of RGB (Red, Green Blue) color data into PSW (Primary, Secondary, White) color space.
[0023] FIG. 5 is a block diagram of a system architecture for improving color correction;
[0024] FIG. 6 is a process diagram showing the steps to selecting and calculating PSW values and selecting matrix columns for multiplication to obtain the desired color correction;
[0025] FIG. 7 is a block diagram of a film-to-video transfer system utilizing the improved color correction of the present invention to translate digitized image data prior to storing and later retrieving and displaying the translated image data;
[0026] FIG. 8 is a block diagram of a film-to-video transfer system showing a display device performing the improved color correction operation prior to the display of the transferred video data; and
[0027] FIG. 9 is a schematic view of a projection display system utilizing the improved color correction of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] As described above, the spectrum and maximum intensity of the primary color sources, whether color filters acting on a white light beam or light sources capable of outputting light in a portion of the visible spectrum, determine several key characteristics of a display system such as the white point and the purity of the secondary colors.
[0029] For example, a system designer may select a green color filter with a relatively broad pass band in order to provide a very high number of lumens to the projected image-especially when coupled with a light source that outputs a high proportion of its energy in the green spectrum band. The disproportionate amount of green light contributed to the white light output, however, results in the white light having a greenish tinge. While the excess green contributed to the white light may not be objectionable, the high green level will result in secondary colors such as yellow and cyan having too much green. What is needed is an efficient way to individually adjust the purity of not only the primary colors, but also the secondary colors and the white point while preserving a color gamut that is relevant to the display system even though that color gamut may fall outside of a CRT reference display RGB color space.
[0030] A method and apparatus has been developed that enables individual control of multiple color properties in a primary color display system and a range of color space including negative RGB values. The method and apparatus disclosed herein allow the system designer great flexibility in the selection of primary color sources, while providing a means to compensate for the undesirable side effects of the combination of primary color sources and to provide color correction capabilities in an expanded color gamut system.
[0031] While the method and apparatus taught herein with be disclosed primarily in terms of a three-color primary system that uses a white light source in conjunction with three color filters to provide three light beams that are perceived as primary colors, it should be understood that this disclosure is intended to include applications using other means of providing the primary colors such as separate light sources, separate primary color light sources, beam splitters, and color wheels. Furthermore, although this disclosure primarily describes a display system using Red, Green, and Blue (RGB) primary colors, it is intended to include and address other color systems, whether additive or subtractive, such as systems whose component signals include Cyan, Magenta, and Yellow (CMY), Cyan, Magenta, Yellow and Black (CMYK), and luminance and chrominance (YUV) signals.
[0032] FIG. 1 is a CIE 1931 xy chromaticity diagram 100 of a first display system. The color space 101 is the response of the human eye and is beyond replication by the color gamut of an additive color synthesis system. The color space 102 of the display system is determined by the location of the system's red point 104 , blue point 108 , green point 106 , and the relative intensity of the light provided at each of these primary color points. If each primary color provides the same intensity contribution to the white light level, then the secondary color points will be located midway between the primary color points, and the white point 110 will be located at the intersection of the lines connecting the primary and secondary colors as shown in FIG. 1 . In FIG. 1 , the cyan point 112 , yellow point 114 , and magenta point 116 , are all located midway between the primary color points. The white point 110 shown in FIG. 1 is slightly to the magenta side of a reference white line 118 .
[0033] FIG. 2 is a chromaticity diagram 200 of a second display system shown relative to the first display system. The second display system has the same red, and blue points as the display system represented in FIG. 1 , but a new green point 206 has expanded the color gamut and the relative intensity of the primary colors has changed. Because the color space has expanded and shifted, new colors are available and the secondary color points, as well as the white point, are shifted. In the example shown in FIG. 2 , the red light source provides less intensity than the blue light source, and much less than the green light source, resulting in a white point 210 that is shifted toward cyan. The yellow point 214 is shifted toward the green point 106 , and the magenta point 216 is shifted toward the blue point 108 . Although the display system represented by FIG. 2 provides a lot of illumination to a white point that may be suitably close to the reference white line 118 in many applications, when the display system attempts to display a non-primary color represented by linear RGB data, the color will have a greenish or bluish tint. Additionally, the new color space 202 is beyond the operational color spectrum of conventional CRT monitors, and although accounted for in the industry through specifications including ITU-R BT.709 & ITU-R BT.1361, adjustments in an expanded color gamut have been insubstantial. Projectors with a larger color gamut can behave like conventional CRTs and, when negative RGB values are present, show the expanded color gamut whereas conventional CRTs would ignore the negative signals.
[0034] One means of compensating for the undesirable side effects of a given set of primary color sources is to provide secondary color and white information as well as the primary color information, and to use this additional information to generate a set of output primary data that compensates for the undesirable side effects. The secondary color and white intensity information is used to alter the amount each primary color source contributes to the secondary colors and white. In effect, this method transforms a three primary color system into a seven primary color system (RGBCMYW) including the three primary colors (RGB), the three secondary colors (CMY), and white (W) by remapping the color space to provide additional control over the secondary colors and white. The remapping system can be written as:
[ R ′ G ′ B ′ ] = [ Rr Rg Rb Rc Rm Ry Rw Gr Gg Gb Gc Gm Gy Gw Br Bg Bb Bc Bm By Bw ] [ R G B C M Y W ] Equation 1
[0035] Analysis of Equation 1 reveals that the coefficients represent three groups of signals: primary color (P) coefficients, represented by Rr, Rg, Rb, Gr, Gg, Gb, Br, Bg, and Bb; secondary color (S) coefficients, represented by Rc, Rm, Ry, Gc, Gm, Gy, Bc, Bm, and By; and white (W) coefficients, represented by Rw, Gw, and Bw.
[0036] Each primary and secondary color, as well as white, can be controlled independently. For example, by setting the coefficient in location “Gy” to a value less than 1, the amount of green contributing to a yellow color is reduced, without affecting the contribution of green to white, pure green, or cyan. Each color, including the primary colors, can be manipulated in a similar manner—coefficient “Bg” allows blue to be added to green.
[0037] The matrix of Equation 1 provides a powerful tool for the independent control of each of the seven colors (RGBCYMW).
[0038] FIG. 3 is a chromaticity diagram 300 for the display system represented in FIG. 2 after the secondary colors have been altered as described above. As shown in FIG. 3 , the yellow point 314 and magenta point 316 have been moved toward the red point 104 , while the cyan point 312 has been moved toward the blue point 108 .
[0039] The method taught thus far provides for the adjusting of the color response of a display system, but a straight-away implementation of the matrix operation of Equation 1 in a high resolution display system would require, for example, up to 21 multiplication operations, each using 14 bit inputs, 10 to 14 bit coefficients, and providing 14 bit outputs. The image data could be processed as described in Equation 1 and stored for later display. Performing the computations in real time, however, would require more processing power than is economically feasible to include in many display systems at this time. Therefore, there is a great need to simplify the calculations while allowing for negative RBG signals in order to enable the inclusion of the color space control features in display systems that do not have sufficient processing power to implement Equation 1.
[0040] In previous art, the combination of the seven primary color input values (RGBCMYW) could be expressed using only three values, a primary color, a secondary color, and a white level, in PSW color space in a resulting PSW matrix. The contribution of negative RGB pixel values increases the difficulty of calculations and causes conventional calculation methods to break down. Mapping the color space directly to a 3×3 matrix using just relative signal magnitudes would not necessary select the correct coefficient values and may result in erroneous data.
[0041] A solution to providing the correct color correction is to correctly select the color components from the 3×7 matrix of equation 1 using both positive and negative RGB values. The remapping of the seven primary color system to the RGB space is shown in Equation 2.
[ R ′ G ′ B ′ ] = [ PC1 SC1 WC1 PC2 SC2 WC2 PC3 SC3 WC3 ] [ P S C ] Equation 2
[0042] The complexity of implementing Equation 2 is the determination of the values for each of the coefficients PCd, SC1, WC1, PC2, SC2, WC2, PC3, SC3, and WC3. As mentioned above, the primary colors coefficients (P) are represented by Rr, Rg, Rb, Gr, Gg, Gb, Br, Bg, and Bb; the secondary color (S) coefficients are represented by Rc, Rm, Ry, Gc, Gm, Gy, Bc, Bm, and By; and the white (W) coefficients are represented by Rw, Gw, and Bw. Therefore, the first three columns of the coefficient matrix (1, 2, 3) of Equation 1 are used to control the primary colors, the second group of three columns (4, 5, 6) of the coefficient matrix of Equation 1 are used to control the secondary colors. When all RGB values are positive, the last column ( 7 ), controls the white color and when one or two RGB values are negative, a primary color coefficient, Rr, Rg, Rb, Gr, Gg, Gb, Br, Bg, and Bb (columns 1, 2, or 3) controls the white. If all three RGB values are negative, the signal should be clamped to black level since no positive color or luminance information is available. Thus, the coefficients for Equation 2 may be taken directly from the coefficients of Equation 1—by selecting the columns based on the identity of the primary, secondary, and white colors of Equation 2, which is determined by the relative strengths of the red, green, and blue inputs.
[0043] Based on possible R, G, and B signal values, nineteen distinct variations are possible when taking into consideration negative RGB values. To facilitate accurate and timely decisions, a method has been devised as represented in Table 1, below, which provides the method to correlate the 3×7 matrix in Equation 1 to the 3×3 matrix of Equation 2. Using logic based on Table 1, and using the magnitudes of the RGB component and the number of negative components, one can determine the proper PSW calculation and column selection to select the proper 3×3 matrix in which the color correction coefficients will reside.
TABLE 1 3 × 3 Matrix PSW Column # Calculations Select Order Neg r < g g < b r < b r < 0 g < 0 b < 0 P S W Pc Sc Wc 1 r > g > b 0 0 0 0 0 0 0 r-g g-b b 1 6 7 2 r > b > g 0 0 1 0 0 0 0 r-b b-g g 1 5 7 3 g > r > b 0 1 0 0 0 0 0 g-r r-b b 2 6 7 4 g > b > r 0 1 0 1 0 0 0 g-b b-r r 2 4 7 5 b > r > g 0 0 1 1 0 0 0 b-r r-g g 3 5 7 6 b > g > r 0 1 1 1 0 0 0 b-g g-r r 3 4 7 7 r > g > b 1 0 0 0 0 0 1 r-g g b 1 6 3 8 r > b > g 1 0 1 0 0 1 0 r-b b g 1 5 2 9 g > r > b 1 1 0 0 0 0 1 g-r r b 2 6 3 10 g > b > r 1 1 0 1 1 0 0 g-b b r 2 4 1 11 b > r > g 1 0 1 1 0 1 0 b-r r g 3 5 2 12 b > g > r 1 1 1 1 1 0 0 b-g g r 3 4 1 13 r > g > b 2 0 0 0 0 1 1 r g b-g 1 4 3 14 r > b > g 2 0 1 0 0 1 1 r b g-b 1 4 2 15 g > r > b 2 1 0 0 1 0 1 g r b-r 2 5 3 16 g > b > r 2 1 0 1 1 0 1 g b r-b 2 5 1 17 b > r > g 2 0 1 1 1 1 0 b r g-r 3 6 2 18 b > g > r 2 1 1 1 1 1 0 b g r-g 3 6 1 19 don't 3 x x x 1 1 1 0 0 0 1 6 7 care
[0044] FIG. 4 is a graph of an example using three primary color intensity data values (r, g, b) for a single pixel with color intensity values Di, Ei, and Fi corresponding respectively to the R, B, and G signals. In the example, there is one negative color component, R, and the magnitudes of the RGB signals follow the condition g>b>r, which corresponds to case 10 in Table 1. The red intensity (“r”) given by the value “Di” is located in the negative RGB color space, and following the PSW calculations column of the table, red with value “Di” will represent the white (W) component of the pixel. The secondary color component (S) is assigned to the value of the B color component, which has an intensity value “Ei” from FIG. 4 . Contributing to the primary color component (P), Table 1 indicates the calculation corresponding to the values represented by g−b, will be used and the corresponding intensity value would therefore be Fi−Ei. Intensity values from FIG. 4 , assigned to the color components, are summarized by P=Fi−Ei, S=Ei, and W=Di.
[0045] Case 10 in Table 1 dictates that columns 2, 4 and 1 be selected for the P, S, and W matrix columns respectively. This indicates that the primary color component (P) is green, the secondary color component (S) is cyan, and the white color component (W) is red. As shown in this example, the decisions based on the method in table 10 are straightforward and simplify the process. Per the process defined in FIG. 6 (below), the remaining step is to multiply the 3×3 matrix to obtain the corrected RBG value.
[0046] FIG. 5 is a block diagram depicting one embodiment of the improved color correction with negative RGB support. In the figure, RGB data for a given pixel is input into the RGB-to-PSW converter 502 . The RGB-to-PSW converter 502 compares the three intensity values and outputs the greatest on signal P, the median on signal S, and the minimum on signal W. P, S, and W are then driven to one set of inputs in the 3×3 multiplier 504 . The RGB-to-PSW converter 502 also drives three signals to a column selection block 506 . The column selection block 506 provides the coefficients used by the 3×3 multiplier 504 . The output of the 3×3 multiplier 504 is the processed RGB data of Equations 1 & 2.
[0047] FIG. 6 illustrates a process flow for the conversion of color component signal inputs to adjusted color component signals, such as the conversion illustrated in the block diagram of FIG. 5 in which the R′, G′, and B′ signals are created as adjusted signals from input color component signals R, G, and B. In alternative embodiments, adjusted PSW signals can be created from input RGB signals or adjusted RGB signals can be created from input PSW signals.
[0048] In the flow 600 illustrated in FIG. 6 , at block 602 the intensity of the input color component signals, RGB, are measured and are assigned numeric values. Pixels of the image are then categorized at block 604 according to their respective magnitudes and in accordance with the cases specified in the exemplary Table 1, above.
[0049] In further accord with Table 1, PSW values are calculated at block 606 by the RGB-to-PSW conversion circuit 502 (see FIG. 5 ). At block 608 , then, the coefficient values for the matrix multiplication, or more generally matrix operation, circuit 504 are selected according to the detected color intensity data values and further in accordance with the exemplary selections of Table 1. At this process block, using the 3×7 matrix column selection circuit 506 in the example of FIG. 5 , the coefficients for the matrix operation are applied in the matrix operation circuit 504 .
[0050] Still referring to FIG. 6 , at process block 610 the matrix operation circuit 504 will operate on the PSW signals (or other signals, according to the particular application) to generate the adjusted color component signals in accordance with the selected matrix coefficients.
[0051] The concepts taught herein can be extended to the use of other points in the color space without departing from the intended teachings hereof. For instance, the color correction can be implemented before or after a gamma correction operation, or implemented as part of the degamma scaling operation. Likewise, other embodiments use logic thresholds to sample YC R C B values to determine the proper primary and secondary colors and implement the color correction techniques in a Y′C R ′C B ′ to R′G′B′ conversion matrix.
[0052] The color correction described herein is applicable to both additive and subtractive color systems. The term “combined primary” will be used to describe the mixture of all of the primary colors whether describing white in an additive system or black in a subtractive system.
[0053] FIG. 7 is a block diagram of a film-to-video transfer system 700 utilizing the improved color correction 702 of the present invention to translate digitized image data prior to storing the digitized data.
[0054] The color correction described may be performed by an image transfer-machine or scanner 703 when capturing or digitizing an image so that color corrected data is produced, or the color correction may be performed by the display system as an image is being displayed. The color corrected data may be stored in a digital storage medium 706 later retrieved and displayed by display system 704 .
[0055] Alternatively, in accordance with FIG. 8 , the color correction is included in an enhanced gamut display system 802 to provide color correction for input image signals. The figure shows a display system 802 with the improved color correction 804 capability. The color correction 804 can be selected by a viewer, for example through the use of a remote control and on-screen programming, to enable the viewer to select from several color correction modes. The use of multiple color correction modes allows the user to optimize the color correction based on the selected image source.
[0056] FIG. 9 is a schematic view of an image projection system 1000 incorporating the improved color correction of the present invention. In FIG. 10 , light from light source 1004 is focused on a micromirror array 1002 by lens 1006 . Although shown as a single lens, lens 1006 may comprise a group of lenses and mirrors, which together focus and direct light from the light source 1004 onto the surface of the micromirror device 1002 . Controller 1014 receives image intensity data and control signals and processes them according to the teachings herein to obtain color corrected image intensity data signals. The color corrected image intensity data signals are then transferred from controller 1014 to the micromirror device 1002 . The color corrected image intensity data causes some mirrors to rotate to an on position and others to rotate to an off position. Mirrors rotated to an off position reflect light to a light trap 1008 while mirrors rotated to an on position reflect light to projection lens 1010 , which is shown as a single lens for simplicity. Projection lens 1010 focuses the light modulated by the micromirror device 1002 onto an image plane or screen 1012 .
[0057] Thus, although there has been disclosed to this point a particular embodiment for a method and apparatus for improved color correction, it is not intended that such specific references be considered as limitations upon the scope of this invention except insofar as set forth in the following claims. Furthermore, having described the invention in connection with certain specific embodiments thereof, it is to be understood that further modifications may now suggest themselves to those skilled in the art, it is intended to cover all such modifications as fall within the scope of the appended claims. | Disclosed is a system for adjusting a plurality of component color signals for expanded color gamut displays. The disclosed system comprises an input for receiving the component color signals, a detection circuit ( 502 ) connected to the input and configured to detect at least one characteristic of the received component color signals, and an adjustment circuit ( 504 ) connected to the input for receiving the component color signal and for creating adjusted component color signals from the received component color signals according to a certain technique, where the certain technique is changed according to the detected characteristic. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims the priority of German Application No. 196 36 659.3 filed Sep. 10, 1996, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
This invention relates to a fluid-operated striker assembly which has a striker piston movable in a working cylinder and adapted to strike a tool bit as well as a control system having a control plunger movable in a control valve. The striker piston has two piston faces of different sizes. The smaller piston face is effective in the direction of the return stroke and is continuously connected with a pressure conduit in which working pressure prevails. The larger piston face is effective in the direction of the working stroke (forward stroke) and is alternatingly connected by the control valve with the pressure conduit and with a depressurized return conduit. The control plunger has two control faces of different sizes, operating in opposite directions. The smaller control face which is effective in the direction of the return stroke position of the control plunger is continuously connected with the pressure conduit whereas the larger control face is, by means of a circumferential groove situated between the piston faces, alternatingly and only for certain periods connected with the pressure conduit and the depressurized return conduit.
A striker assembly of the above-outlined type is disclosed, for example, in German Patent No. 3,443,542 to which corresponds U.S. Pat. No. 4,646,854 issued Mar. 3, 1987. By using a particular holding or switching valve which is incorporated in the control conduit cooperating with the control system and which is alternatingly also connected with the return conduit, it is sought to be ensured that even in case of a reflection of the striking energy from the tool bit to the striker piston, such reflected energy is hydraulically regained whereby an increase of the striking frequency of the striker piston is achieved.
Fluid-operated striker assemblies, particularly hydraulic hammers, are generally used for breaking up rocks or concrete. For such an operation the kinetic energy of a striker piston is transmitted to the tool bit by delivering blows thereto by the striker piston, and the kinetic energy is converted to comminuting work at the tool bit tip. In case of relatively hard materials, only one part of the kinetic energy is converted to comminuting work, dependent upon the hardness of the material to be comminuted. The unconverted energy portion is reflected by the tool bit to the striker piston and may be used, with a suitable device, to increase the striking frequency. In contrast, in case of relatively soft materials, the striking (kinetic) energy is fully converted to comminuting work. The softer the material the greater the comminuting effect of the tool bit and the deeper the penetration of the tool bit into the material.
Processes in which the applied striking energy is higher than the energy required for the comminution are undesirable because of the resulting higher stresses on the striker assembly. The rapid adaptation of the striking energy to all operational conditions is a significant condition for a longer service life of the striker assembly and for an optimal comminution of material.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved fluid-driven striker assembly of the above-outlined type in which the individual striking energy is reduced before the material to be comminuted is broken.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the fluid-operated striker assembly includes a working cylinder and a striker piston slidably received in the working cylinder for executing working (forward) and return strokes. The striker piston delivers a blow to a tool bit during the working stroke when the striker piston is either in a limit position or in an advanced position which is beyond the limit position in the direction of the working stroke. A control arrangement applies an alternating fluid pressure to the striker piston to execute the working and return strokes. Further, a precontrol arrangement is provided for affecting the control arrangement dependent on whether the striker piston has exceeded its limit position. The precontrol arrangement causes the control arrangement to operate the striker piston with a normal working stroke as long as the striker piston delivers a blow to the tool bit in the limit position, and causes the control arrangement to operate the striker piston with a short working stroke--whose length is less than that of the normal working stroke--as long as the striker piston delivers a blow to the tool bit in the advanced position.
Thus, the invention provides for a suitable reaction to the properties and behavior of the material to be comminuted upon each individual strike of the striker piston. In case the tool bit penetrates into the material, the striker piston executes only a short working stroke, as a result of which the individual striking energy is small. In case the tool bit does not penetrate into the material (normal operation), the striker piston executes a large (normal) working stroke so that the individual striking energy has a maximum value.
According to an advantageous feature of the invention, the precontrol arrangement includes a precontrol valve which is provided with a resetting arrangement and which, driven by a force directed opposite to the resetting effect, is moved from its open position into a closed position. In the open position a connection is maintained between an additional conduit and a short-stroke conduit; such a connection is interrupted in the closed position. The setting force working opposite the resetting force is generated by charging that setting face of the precontrol valve with the working pressure periodically prevailing in a precontrol conduit which is effective in the direction of the closed position.
According to a further feature of the invention, the larger plunger face of the control plunger communicates with a switch-over conduit whose outlet in the cylinder chamber of the working cylinder is situated in the region of the depressurized circumferential groove (between two lands of the striker piston) in case the striker piston assumes the normal striking position. Accordingly, at that moment only the smaller plunger face is effective in the direction of the return-stroke position of the control plunger. Further, the precontrol conduit is connected with the cylinder chamber of the working cylinder via an outlet which is situated behind the outlet of the switch-over conduit as viewed in the direction of the working stroke of the striker piston. By virtue of the mutual arrangement of the two conduit outlets in the normal operation (that is, as long as the tool bit does not penetrate into the material to be comminuted), during the working stroke of the striker piston only the outlet of the switch-over conduit is open and thus the circumferential groove of the striker piston establishes communication with the depressurized return conduit. Based on the pressure drop in the switch-over conduit, the control plunger moves into the return-stroke position under the effect of the resetting force applied to its smaller plunger face.
In case the tool bit penetrates into the material to be comminuted and thus the striker piston moves beyond the normal position (limit position) in the direction of the working stroke, the outlet of the precontrol conduit is also opened and is depressurized via the circumferential groove of the striker piston. Accordingly, the precontrol valve is shifted by the return force from its closed position into its open position.
According to a preferred embodiment of the invention, the precontrol valve has a setting face effective in the direction of its open position. This setting face which is charged with the working pressure from the pressure conduit is smaller than the setting face effective in the direction of the closed position of the precontrol valve. In such an arrangement the precontrol valve is thus provided with a purely hydraulically operating resetting arrangement.
As an alternative, a mechanically operating resetting element may be connected parallel with the smaller setting face of the precontrol valve; the resulting total resetting force is smaller than the counterforce derived from the pressurization of the larger setting face. It is a result of such a combined mechanical/hydraulic resetting arrangement that in each instance upon starting, the striker assembly first operates in the short-stroke mode.
It is also feasible according to the invention to provide a purely mechanical arrangement to effect resetting.
It is to be understood that the setting face of the precontrol valve effective in the closing direction also may have a mechanical element (such as a spring) for supporting the switch-over process. In such a case, in each instance upon starting, the striker assembly first operates in the long-stroke (normal-stroke) mode.
According to a further feature of the invention, a precontrol branch conduit extends from the precontrol conduit and, separated from the additional conduit, is connected to an output of the precontrol valve and is charged with the working pressure in the closed position of the precontrol valve. In the absence of particular circumstances or geometrical conditions, the precontrol branch conduit is provided with a flow restrictor, preferably a throttle.
In the simplest case a hydraulic resetting of the precontrol valve is effected by providing that its smaller setting face is charged with the working pressure from the pressure conduit by means of a precontrol resetting conduit and a precontrol pressure conduit.
According to a further advantageous feature of the invention, the precontrol pressure conduit is at the input side coupled to the precontrol valve in such a manner that in the closed position of the latter the precontrol pressure conduit is connected with the precontrol branch conduit. In this manner the precontrol valve is moved or, as the case may be, is maintained firmly in its closed position by the pressurization of its larger setting face as long as the precontrol conduit connected with the precontrol branch conduit is not open and thus depressurized.
According to another advantageous feature of the invention the precontrol valve is structured such that in its open position the short-stroke conduit is simultaneously connected with the additional conduit and the precontrol branch conduit. In this manner the pressure conditions in the three interconnected conduits may be mutually affected and adapted to one another. This applies particularly for the pressure conditions in the additional conduit and in the precontrol branch conduit as well as in the precontrol conduit in case the short-stroke conduit is blocked periodically during the working stroke of the striker piston. It is a result of the above-described interconnection that the precontrol branch conduit always remains depressurized in the open position of the precontrol valve, because the control conduit too, is depressurized and therefore the precontrol valve is maintained in its open position.
According to yet another advantageous feature of the invention, the short-stroke conduit is connected with the cylinder chamber of the working cylinder by an outlet which--as viewed in the direction of the working stroke--is situated behind the outlet of the pre-control conduit. It is a result of such an arrangement that during the return stroke motion of the striker piston the latter first opens the short-stroke conduit and is thus exposed to working pressure and simultaneously the precontrol conduit is exposed to pressure with the result that the precontrol valve--at an early moment after a short stroke--is moved into its closed position. In the same manner the control valve switches over to the working stroke position.
Departing from the previously outlined arrangement (where a precontrol branch conduit and an additional conduit are attached to the precontrol valve at its output side), the precontrol valve, at the output side, may be additionally connected by means of a switching conduit to the alternating pressure conduit for the rearward cylinder chamber portion. In such an arrangement in the closed position only a connection between the precontrol pressure conduit and the precontrol branch conduit exists, while the short-stroke conduit, the additional conduit and the switching conduits are closed by the precontrol valve. In the open position, on the one hand, the precontrol branch conduit and the switching conduit and, on the other hand, the short-stroke conduit as well as the additional conduit are connected with one another via the precontrol valve while the precontrol pressure conduit is closed. It is a result of such an arrangement that the precontrol valve may at all times switch over to the closed position only after the control plunger has assumed its working-stroke position and accordingly, in the alternating pressure conduit for the rearward cylinder chamber portion a pressure prevails which also affects the precontrol branch conduit and the precontrol conduit by means of the switching conduit.
Departing from the earlier-described embodiments, the short-stroke conduit exposed to the working pressure is connected to the input of the precontrol valve with the interposition of a pressure controlled timing unit which is switched to its inoperative position as long as the working pressure prevails in the alternating pressure conduit connected with the rear cylinder chamber portion.
The timing unit has a pressure sensor, a timing member controlled by the pressure sensor and a shut-off valve controlled by the timing member. The pressure sensor converts the working pressure prevailing in the precontrol conduit into a control signal and dependent on the signal magnitude, sets a time period during which the shut-off valve assumes its open position. It is an advantage of such an arrangement that the magnitude of the "short stroke" about to be triggered may be varied and may also be externally (manually or by remote control) affected by an appropriate setting of the timing member. It is essentially a desideratum that upon a dropping of the working pressure the timing member reduces the period for the open position of the shut-off valve. The resetting of the timing unit is made possible by connecting it via a timing conduit with the alternating pressure conduit.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a hydraulic circuit diagram of a striker assembly according to a preferred embodiment of the invention, in which the precontrol valve is reset by hydraulic means.
FIG. 2 is a hydraulic circuit diagram of a striker assembly according to another preferred embodiment of the invention, in which the precontrol valve is reset by mechanical means.
FIG. 3 is a hydraulic circuit diagram of a striker assembly according to a further preferred embodiment of the invention, in which the precontrol valve is reset by combined hydraulic/mechanical means.
FIG. 4 is a hydraulic circuit diagram of a striker assembly according to yet another preferred embodiment of the invention, in which the precontrol valve is structured and switched differently from the embodiments of FIGS. 1, 2 and 3.
FIG. 5 is a hydraulic circuit diagram of a striker assembly as shown in FIG. 1, including a pressure controlled timing unit.
FIG. 6 is a hydraulic circuit diagram of the arrangement of FIG. 5, showing further details.
FIG. 7 is a circuit diagram showing details of the timing unit illustrated in FIGS. 5 and 6.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The striker assembly generally designated at 1 in FIGS. 1-5 has a working cylinder 2 receiving a striker position 3 for axial reciprocation therein. The striker piston 3 has two lands 3a and 3b separated from one another by a circumferential groove 3c. The piston faces A1 and A2 which are radial annular surface parts of the lands 3b and 3a, respectively, and which are oriented axially outwardly, that is, away from the circumferential groove 3c, bound a rearward and a frontal cylinder chamber portion 2a and 2b, respectively. The piston face A1 has an area which is less than that of the piston face A2.
Externally of the working cylinder 2 the striker piston 3 has a downstepped striker tip 3d which cooperates with a rearward terminal radial shank face of a tool bit, such as a chisel 4. The motion of the striker piston 3 in the direction of the working stroke (forward stroke) is designated by an arrow 3e.
FIG. 1 (similarly to FIGS. 2-5) shows the striker assembly in a state immediately following the impacting of the chisel 4 by the striker piston 3. A normal operation is assumed, that is, the chisel 4 does not penetrate into the material to be comminuted and thus the striker piston 3 assumes a normal, predetermined impacting position.
The control arrangement for a switch-over of the motion of the striker piston 3 includes a control plunger 5a movable within a control valve 5. The smaller plunger face S1 is continuously exposed to the working pressure (that is, the system pressure) by means of a resetting conduit 6. The system pressure is generated by an energy source, such as a hydraulic pump 7. The smaller piston face A1 too, is continuously exposed to the working pressure by means of a pressure conduit 8 which communicates with the resetting conduit 6. The outlet 8a of the pressure conduit 8 is arranged relative to the working cylinder 2 such that it is situated at all times externally of the piston land 3b and thus is always positioned in the frontal cylinder chamber portion 2b.
The larger plunger face S2 of the control plunger 5a is coupled by means of a switch-over conduit 9 with the working cylinder 2 such that its outlet 9a is, in the shown operational state, coupled to a depressurized return conduit 10 via the circumferential groove 3c. The outlet 9a of the switch-over conduit 9 and the outlet 10a of the return conduit 10 are thus situated at a distance from one another (measured in the axial direction of the striker piston 3) which is less than the axial length of the circumferential groove 3c.
The control valve 5 is connected, on the one hand, by a control conduit 11 to the pressure conduit 8 and, on the other hand, via a return conduit 12 to the sump 12a in which the return conduit 10 also terminates. Further, the control valve 5 is connected to the rearward cylinder chamber portion 2a by means of an alternating-pressure conduit 13. The larger piston face A2 is adapted to be exposed to the working pressure (system pressure) that can be supplied to the cylinder chamber portion 2a by the alternating-pressure conduit 13.
The control valve 5 may assume two valve positions, namely, the illustrated (right-hand) return-stroke position in which the larger piston face A2 is depressurized via the alternating-pressure conduit 13 and the return conduit 12 and the (left-hand) working-stroke position in which the rearward cylinder chamber portion 2a is charged with the working pressure by means of the pressure conduit 8, the control conduit 11 connected to the pressure conduit 8 and the alternating-pressure conduit 13. As a result of such an operational state, the striker piston 3 executes a working stroke in the direction of the arrow 3e against the resetting force with which the smaller piston face A1 is charged.
According to the invention the striker assembly 1 further has a precontrol arrangement including a precontrol valve 14 which may assume either the illustrated (upper) closed position or a (lower) open position.
The position of the pre-control valve 14 is determined by the pressures applied to two faces of the plunger 14a of the pre-control valve 14, namely, the smaller setting face V1 and the larger setting face V2. The setting face V2 is coupled via a precontrol conduit 15 with the cylinder chamber of the cylinder 2. The outlet 15a of the precontrol conduit 15 is situated behind the outlet 9a of the control conduit 9 as viewed in the direction of the working stroke (arrow 3e). The precontrol conduit 15 is connected by means of a precontrol branch conduit 15b to the output side of the precontrol valve 14. The precontrol branch conduit 15b contains a throttle 16.
The smaller setting face V1 of the plunger 14a is connected to the pressure conduit 8 via a precontrol resetting conduit 17a and is thus continuously exposed to the working pressure. The precontrol valve 14 seeks to assume its open position under the effect of the resetting force exerted on the setting face V1.
At its input side the precontrol valve 14 is connected, on the one hand, to the cylinder chamber of the working cylinder 2 by means of a short-stroke conduit 18 having an outlet 18a and, on the other hand, to the pressure conduit 8 by means of a precontrol-pressure conduit 17. The outlet 18a of the short-stroke conduit 18 is located behind the outlet 15a of the precontrol conduit 15 as viewed in the direction of the working stroke (arrow 3e). At the output side the pre-control valve 14 is connected (as noted earlier), on the one hand, to the precontrol conduit 15 by means of the precontrol-branch off conduit 15b and, on the other hand, to the switch-over control conduit 9 for the control valve 5 by means of an additional conduit 19.
As illustrated, in the (upper) closed position of the precontrol valve 14 the precontrol pressure conduit 17 is connected with the precontrol conduit 15 by means of the precontrol-branch conduit 15b and in this manner--by virtue of its larger setting face V2--a setting force in the direction of the closed position is generated. Further, in the illustrated closed position the short-stroke conduit 18 and the additional conduit 19 are shut off in the direction of the pre-control valve 14.
In the (lower) open position of the precontrol valve 14 the short-stroke conduit 18 is simultaneously connected with the precontrol-branch conduit 15b and the additional conduit 19 while the precontrol-pressure conduit 17 is blocked. Dependent upon the position of the striker piston 3 relative to the outlet 18a of the short-stroke conduit 18, either the pressure conditions in the conduits 15, 15b, 19 and 18 or only the pressure conditions in the conduits 15, 15b and 19 are adapted to one another. The latter is the case if--as illustrated--the outlet 18a of the short-stroke conduit 18 is closed towards the cylinder chamber of the working cylinder 2 by the land 3b of the striker piston 3.
In the description which follows, the normal operation (long-stroke operation) of the striker assembly according to the invention will be set forth.
After switching over the control valve 5 into the (left-hand) working-stroke position, the motion of the striker piston 3 is initiated in the direction of the working stroke (arrow 3e) after having reached its upper point of reversal (upper dead center). The precontrol valve 14 assumes its illustrated closed position and is maintained in such a closed position by the pressure communicated thereto by the pre-control pressure conduit 17 (since working pressure is applied to both setting faces V1 and V2 of the precontrol valve 14)
When the striker piston 3 impacts upon the chisel 4, the switch-over control conduit 9 is depressurized via the circumferential groove 3c and the return conduit 10, as result of which the control plunger 5a of the control valve 5 switches over to the illustrated return-stroke position under the effect of the return force derived from the smaller control surface S1 and thus initiates the return stroke of the striker piston 3. In case the chisel 4 does not penetrate into the material to be comminuted, the striker piston 3 does not leave its intended, normal impacting plane where it hits the shank end of the chisel 4, so that the outlet 15a of the precontrol conduit 15 remains closed by the land 3b. The striker piston 3 executes its return stroke as long as the additional conduit 9 is coupled, through its outlet 9a, with the pressure conduit 8 via the frontal cylinder chamber portion 2b. Accordingly, to the larger control face S2 the working pressure is applied whereby the control plunger 5a is moved into the (left-hand) working-stroke position in which it connects the rearward cylinder chamber portion 2a with the pressure conduit 8 via the control conduit 11 and thus initiates a new working stroke.
If during operation of the striker assembly the position of the impacting plane between the striker piston 3 and the chisel 4 shifts in the direction of the working stroke (that is, the chisel penetrates into the material to be comminuted) the following operational processes take place:
After switching over the control valve 5 into the working stroke position and the precontrol valve 14 into the closed position, the striker piston 3 first executes a working stroke. If during execution of such a working stroke the chisel 4 penetrates into the material to be comminuted, the striker piston 3 leaves its normal impacting plane and follows the chisel 4, thus assuming an "advanced" position. As a result of such a shift, the outlet 15a of the precontrol conduit 15 which is initially closed by the piston land 3b, is opened and is depressurized by virtue of the hydraulic connection established via the annular groove 3c and the return conduit 10. Accordingly, the precontrol valve 14 switches over from its closed position to the open position, whereby the short-stroke conduit 18 is coupled to the additional conduit 19 which, in turn, is depressurized via the switch-over conduit 9, the annular groove 3c and the return conduit 10. By virtue of such a depressurization the control valve 5 too, has switched into the return stroke position whereby the striker piston 3 executes its return stroke.
Upon executing a smaller-than-normal stroke, also referred to as the "short stroke", the outlet 18a of the short-stroke conduit 18 is opened and is coupled with the pressure conduit 8 via the frontal cylinder chamber portion 2b. By means of the short-stroke conduit 18 which is thus exposed to working pressure, the conduits 15b and 15 and also the conduits 19 and 9 are exposed to pressure with the intermediary of the precontrol valve 14, as a result of which the control valve 5 is, prior to reaching the maximum possible stroke, switched over into the (left-hand) working-stroke position and again, a working stroke is initiated. At the same time, as a result of exposing the larger setting face V2 of the precontrol valve 14 to the working pressure, the precontrol valve 14 is caused to move into the illustrated closed position against the return force exerted on the smaller setting face V1.
The arrangement according to the invention thus makes it possible for the striker assembly to react, upon each individual blow of the striker piston 3 to the chisel 4, to the properties or behavior of the material to be comminuted. In case the tool bit penetrates into the material to be comminuted, the striker piston executes only a short stroke so that the individual striking energy is low. In case the tool bit does not penetrate into the material to be comminuted, a larger stroke (normal stroke) is executed with a correspondingly maximum individual striking energy.
In the embodiment according to FIG. 2, the precontrol valve 14 has a purely mechanical resetting arrangement formed of a spring element 20. Accordingly, in such an embodiment neither a pressurizable setting face V1 nor a precontrol return conduit 17a of the earlier-described embodiment are present.
In the embodiment according to FIG. 3 the precontrol valve 14 is provided with a combined mechanical/hydraulic resetting arrangement. For this purpose, a mechanical resetting element, such as a spring 21 is connected in parallel with the smaller setting face V1 which is coupled to the pressure conduit 8 by means of the precontrol return conduit 17a. The total resetting force generated by means of the force derived from the setting face V1 and the spring 21 is less than the counterforce derived from the larger setting face V2 when the latter is charged with pressure. By virtue of the spring 21 the precontrol valve 14 assumes its open position when the striker assembly is switched off and therefore the striker piston 3 initially always operates in the short-stroke mode.
In contrast to the embodiments described before, the embodiment according to FIG. 4 has a precontrol valve 14 which has two coupling ports at its input side and three coupling ports at its output side. In addition, the precontrol valve 14 is, at its output side, connected by a switching conduit 22 with the alternating-pressure conduit 13. Thus, the precontrol valve 14 is designed such that in the illustrated (upper) closed position only a connection between the precontrol pressure conduit 17 and the precontrol branch conduit 15b to the precontrol conduit 15 is present, while at the input side the short-stroke conduit 15 and at the output side the additional conduit 19 as well as the switching conduit 22 are closed. In the (lower) open position, the switching conduit 22 is connected to the precontrol branch conduit 15b and the short-stroke conduit 18 is connected to the additional conduit 19. The precontrol pressure conduit 17 is closed at the input side of the precontrol valve 14.
As a result of the design and outlay of the precontrol valve 14 according to the FIG. 4 embodiment, switching from the open position into the closed position is triggered only after the control valve 5 has reached its working-stroke position and accordingly, the alternating pressure conduit 13 is charged with working pressure. By means of the switching conduit 22 in which then too, working pressure prevails, the precontrol branch conduit 15b is pressurized, and, as a result, under the effect of the larger setting face V2, a switch-over of the precontrol valve 14 into the closed position is triggered.
Departing, for example, from the embodiment shown in FIG. 1, the striker assembly 1 according to FIG. 5 has a short-stroke conduit 18 which is connected to the pressure conduit 8 by means of the precontrol-pressure conduit 17 with the intermediary of an only symbolically illustrated pressure-controlled timing unit 23 which has a pressure sensor, a timing member controlled by the pressure sensor and a shut-off valve controlled by the timing member. The pressure sensor converts the working pressure prevailing in the precontrol pressure conduit 17 to a control signal and dependent from the magnitude of such a signal, the timing member sets the duration during which the shut-off valve assumes its open position in which it establishes communication between the short-stroke conduit 18 and the precontrol pressure conduit 17. The pressure sensor affects the timing member in such a manner that the duration set by the timing member becomes shorter as the working pressure (system pressure) drops.
As seen in FIG. 6, the timing unit 23 is additionally connected with the alternating-pressure conduit 13 by a timing conduit 24, by means of which the timing unit 23 is placed into its inoperative state as long as the alternating pressure conduit 13 connected with the rearward cylinder chamber portion 2a is charged with working pressure. The timing unit 23 starts operating when a pressure drop occurs in the alternating-pressure conduit 13.
In the embodiment according to FIG. 7, the shut-off valve 23a of the timing unit 23 is for control purposes connected, on the one hand, to a resetting conduit 17b by means of which the smaller valve control face B1 may be charged with working pressure and, on the other hand, it is connected to the timing conduit 24 by means of its larger valve control surface B2. The resetting conduit 17b is connected to the pressure conduit 8 by means of the precontrol resetting conduit 17a. In the illustrated closed position the short-stroke conduit 18 extending from the resetting conduit 17b is closed towards the precontrol valve 14 by means of the shut-off valve 23a.
For setting a time period, the timing conduit 24 is provided with a flow resistance such as a constriction 23b. A check valve 23c is connected in parallel with the constriction 23b to provide for a rapid resetting of the shut-off valve 23a into the illustrated closed position. In the open position of the shut-off valve 23a the short-stroke conduit 18 is connected with the pressure conduit 8 by means of the resetting conduit 17b and the precontrol resetting conduit 17a.
In case working pressure prevails in the alternating pressure conduit 13, the shut-off valve 23a assumes--against the resetting force derived from the smaller valve control surface B1--the illustrated closed position in which a connection between the short-stroke conduit 18 and the pressure conduit 8 is interrupted. If the pressure decreases in the alternating-pressure conduit 13, the pressure prevailing in the timing conduit 24 also drops and, as a result, the shut-off valve 23 begins to switch over to the open position. After a time lapse caused by the constriction 23b, the shut-off valve 23a eventually assumes its open position as a result of which the short-stroke conduit 18 is charged with working pressure.
As soon as the precontrol valve 14 assumes its non-illustrated open position, the control valve 5 is moved into the working-stroke position and thus initiates the working stroke of the striker piston 3.
As soon as working pressure prevails in the alternating-pressure conduit 13 after switching over the control valve 5 (see in this connection, for example, FIG. 1) the larger valve control surface B2 of the shut-off valve 23a is exposed to pressure from the timing conduit 24 in the open state of the check valve 23c, whereby the shut-off valve 23a is reset into its shown initial, closed position.
The advantage of the arrangement illustrated in FIGS. 5, 6 and 7 resides in that the magnitude of the stroke executed by the striker piston 3 may be changed automatically and steplessly as a function of the working pressure. In this manner it is also possible to control externally--for example, manually or by remote control--the time period determined by the timing member and thus to take into account various conditions of operation and application.
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 fluid-operated striker assembly includes a working cylinder and a striker piston slidably received in the working cylinder for executing working (forward) and return strokes. The striker piston delivers a blow to a tool bit during the working stroke when the striker piston is either in a limit position or in an advanced position which is beyond the limit position in the direction of the working stroke. A control arrangement applies an alternating fluid pressure to the striker piston to execute the working and return strokes. Further, a precontrol arrangement is provided for affecting the control arrangement dependent on whether the striker piston has exceeded its limit position. The precontrol arrangement causes the control arrangement to operate the striker piston with a normal working stroke as long as the striker piston delivers a blow to the tool bit in the limit position, and causes the control arrangement to operate the striker piston with a short working stroke--whose length is less than that of the normal working stroke--as long as the striker piston delivers a blow to the tool bit in the advanced position. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an electronically controlled anti-lock braking system (ABS) for a motor vehicle.
2. Description of Related Art
Electronically controlled ABS systems are known in which a microprocessor is used to control release of the brakes of a motor vehicle in response to a determination by the microprocessor that the brakes have locked or are approaching a locked up condition. When such a determination is made, a signal from the controller typically actuates an electro-magnetic brake release, e.g., a solenoid controlled valve in the brake system.
A determination of wheel locking generally requires measurement of actual wheel speed or deceleration, and a determination that the actual wheel speed or deceleration is respectively lower than or greater than a predetermined wheel speed or deceleration limit indicative of an incipient wheel lock situation. It is also possible to make the determination based on a measurement of actual G-force force and comparison with a wheel-speed derived G-force curve.
Such systems are all subject to the common problems of spurious determinations resulting from controller malfunction, and malfunctions in the electro-magnetic brake release. Improper functioning of the ABS can, of course, lead to disastrous consequences, either from failure to release the brakes when the wheels are locked, or from an unintended brake release when braking is required.
As a result, it has been proposed to provide fail-safe circuits for the main controller, and to provide feedback from the brake release to the controller in order to permit the controller to monitor the brake release. Such proposals have not proven to be adequate, given the life-threatening potential of even one malfunction.
A typical "fail-safe" ABS is shown in U.S. Pat. No. 4,700,304, to Byrne et al. In Byrne et al, an analog fail-safe circuit is provided which includes a fuse in series with the drive circuits of an electro-magnetic brake release. When the fuse is blown, the brake release is prevented from operating.
The central ABS controller is a microprocessor which sends out periodic pulses to the fail-safe circuit which disables the fail-safe means from blowing the fuse. The fail-safe circuit of Byrne et al. cannot act independently of the microprocessor, being completely dependent on proper output by the microprocessor of the periodic pulses. If no pulse is received within a predetermined period of time, the fuse automatically blows, but as long as the pulses are received, the fail-safe means is disabled.
An analog system of the type shown in Byrne et al., in addition to being subject to such microprocessor internal errors as, for example, misreading of a brake-release feedback signal, suffers from an unacceptably slow response time. As a result, it has been proposed to substitute a microprocessor for the conventional analog fail-safe circuit.
An example of a system which uses separate microprocessors for detecting malfunctions is disclosed in U.S. Pat. No. 4,709,341 to Matsuda. In Matsuda, identical microprocessors are provided which monitor each other in addition to performing as ABS controllers for respective wheels of the motor vehicle. Dee to costs, such a system is suitable only where separate controllers are required, and in addition suffers from the drawback that it is subject to systematic errors from such sources as radio frequency interference and power supply fluctuations which affect all of the identical microprocessors of Matsuda in exactly the same way due to their identical structure and functions.
SUMMARY OF THE INVENTION
It is an object of the invention to overcome the drawbacks of the prior art by providing an ABS fail-safe controller which includes a fail-safe microprocessor independent of the main controller. The fail-safe microprocessor of the subject invention is capable of disabling a brake-release means either upon detection of main controller malfunction or upon detection of brake-release failure.
The fail-safe microprocessor is programmed to read periodic pulses from the main controller, the pulses being indicative of proper main controller operation, and to prevent the brake-release from operating when the pulses are not detected.
Furthermore, even when pulses are detected, indicating proper main controller operation, the fail-safe microprocessor will still disable the brake-release upon detecting, independently of the main microprocessor, that the brake-release is malfunctioning. Separate feedback lines are provided to permit both the main controller and the fail-safe microprocessor to monitor the brake-release.
The fail-safe microprocessor is advantageously a one-bit microprocessor programmed to monitor several different brake-release means without the need for multiple analog fail-safe circuits.
Control of the brake-release means is preferably implemented via a switch in the drive circuit of the brake-release and responsive to pulses output by the one-bit microprocessor, failure of which automatically opens a switch.
An especially advantageous embodiment of the one-bit microprocessor includes a timer for independently monitoring the solenoid on-time of the brake-release, the microprocessor being capable of shutting down the brake-release if the on-time exceeds a predetermined value.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a preferred embodiment of the invention.
FIGS. 2 and 3 illustrate the operation of the fail-safe microprocessor of the preferred embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows the main elements of an exemplary ABS fail-safe system according to the present invention. In FIG. 1, controller 1 is a control circuit or control microprocessor for determining an incipient wheel-lock condition in response to an input from wheel speed sensor 2 along line 3.
The wheel speed sensor 2 is responsive to the passage of magnetic elements 4 which rotate with, for example, the differential gearing of a motor vehicle axle (not shown), and thus provides a signal indicative of the speed of the wheel or wheels connected to the axle. An especially advantageous sensor of this type is shown in U.S. Pat. No. 4,724,935 to Roper, incorporated herein by reference, although any sensor arrangement which provides a signal indicative of wheel speed or changes in wheel speed could be used in connection with the preferred embodiment of this invention.
The controller 1 may, for example, be a microprocessor of the type shown in the above-mentioned patent to Roper, incorporated by reference herein, which operates by selecting, according to input from the wheel speed sensor, an appropriate deceleration reference curve. The selected reference curve, when crossed by an actual wheel speed curve, indicate an incipient wheel lock condition, and the controller subsequently provides a signal which causes braking pressure to be reduced, releasing the brakes.
The main controller 1 of the preferred embodiment, however, need not be limited to the particular controller described above. The specifics of incipient wheel lock determination form no part of the instant invention. The preferred fail safe system may be applied to a wide variety of main ABS controllers.
Upon determination of an incipient wheel lock condition, main controller 1 provides a signal along line 9 to brake-release drive circuit 7 which causes drive circuit 7 to actuate solenoid 8, opening a valve 8' for modulating the brakes B of the vehicle (not shown).
In order to ensure that short circuits between the vehicle frame and the solenoid minimally affect the controller, the solenoid is switched on its high voltage side. For example, one side of the solenoid may be pulled high to 12 volts when turned on by the controller. If the high side solenoid lead shorts to the frame, the control system fails safe and does not turn the solenoid on, preventing damage to the controller.
When the main ABS microprocessor 1 is operating properly, it provides a periodic signal along status line 13 to a fail-safe microprocessor 5. The periodic signal may be in the form of a pulse automatically generated once every cycle of a main control loop, or it may be generated, for example, in response to an internal microprocessor diagnostic routine.
Fail-safe microprocessor 5 is for example a one-bit microprocessor different in type from the main microprocessor. This will lessen the probability of systematic errors in both the main microprocessor and the fail-safe microprocessor.
Fail-safe microprocessor 5 outputs a signal along line 15 through AC coupling integrator 17, which enables brake-drive enable switch 6 when no malfunction is detected by the fail-safe microprocessor. The AC coupling may include capacitors C 1 and C 2 , and resistor R , thus serving to integrate a pulsed output on line 15, which can then be level detected by switch 6.
Failure to receive a periodic signal along status line 13 within a predetermined time period is interpreted by fail-safe microprocessor 5 as a malfunction in the main microprocessor 1, and the fail-safe microprocessor consequently ceases to enable brake-drive enable switch 6, causing the brake-release to shut down.
In addition to lines 13 and 15, which respectively serve to carry signals indicative of main controller health and to carry an independently generated fail-safe signal for controlling drive enable switch circuit 6, lines 11, 12, and 10 are provided to provide feedback to the main microprocessor and the fail safe microprocessor regarding operation of drive enable switch circuit 6 and brake-release drive circuit 7.
Feedback lines 11 and 12 are connected, respectively, between main microprocessor 1 and brake release drive circuit 7, and between main microprocessor 1 and drive enable switch circuit 6. Feedback line 10 is connected between a logic input of fail-safe microprocessor 5 and brake release drive circuit 7. In addition, both main microprocessor 1 and fail safe microprocessor 5 are capable of monitoring additional brake-release solenoid drive circuits, e.g., for each axle of a truck.
Referring to FIGS. 2 and 3, the one-bit microprocessor performs two primary monitoring functions. The first, indicated by reference numeral 1000, is the main microprocessor monitoring function described above. As indicated by function step 1001, if toggling of status line 13 by the main microprocessor fails, then the fail safe microprocessor disables the drive enable switch circuit.
The second function of the fail-safe microprocessor 5, indicated generally by reference numeral 1002, is to monitor the on-time output of the brake-release drive circuit.
The fail safe microprocessor monitors the on-time of the output of the brake-release drive circuit for a predetermined time interval, e.g., 200 ms, as indicated by steps 1004 and 1005 of the on-time algorithm, shown in FIG. 3. If the solenoid which is connected to the output of the brake release drive circuit is still on after the predetermined time interval, then the fail-safe microprocessor disables the drive enable switch circuit to disable the brake release.
The one-bit microprocessor of the preferred embodiment uses a 200 ms timer because at slow vehicle speeds, under appropriate conditions, the main microprocessor algorithm does not require a longer time, and therefore a solenoid on-time of longer than 200 ms would indicate a malfunction and result in an unnecessarily long and possibly hazardous brake release.
However, under certain circumstances, and especially at higher speeds, longer on-times may be needed. This is accomplished in a very simple manner while maintaining the 200 ms fail-safe capability, by pulsing or turning off the brake-release solenoid for short periods to reset the 200 ms interval timer. Under slippery road conditions at high speeds, the main microprocessor may be programmed to require brake-releases of as long as 3 seconds, in which case the solenoid might, by way of example, be momentarily pulsed off every 60 ms to reset the 200 ms interval timer. Such momentary pulsing would not affect the brake release performance of the solenoid.
Thus, the fail-safe microprocessor of the preferred embodiment is responsive to both failure of the main microprocessor and to malfunctions in the solenoid which are independently detected, to shut down the brake-release function of the anti-lock braking system whenever there is a malfunction that could affect braking performance.
It is to be understood that the invention is not to be restricted to the details of the specific embodiment described, but rather that the scope of the invention should be limited only by the appended claims. | A vehicle anti-lock brake system having a main microprocessor and a fail-safe microprocessor of a different type from the main microprocessor, and a device interconnecting the main and fail-safe microprocessors and the remainder of the vehicle braking system so that the fail-safe microprocessor can disable the brake release system independently of the main microprocessor. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/829,160 filed on Oct. 12, 2006.
BACKGROUND OF THE INVENTION
A poke-through device or simply a “poke-through” is a common device that enables power, data or other cabling to pass through a hole in a floor of a structure, generally a concrete floor. A thermal barrier in the form of a fire and/or smoke retardant element, particularly intumescent material, is incorporated within the poke-through to seal the floor opening in the event of a fire. This helps prevent a fire or the smoke from spreading from one floor to the next.
Contemporary poke-throughs provide access between an upper floor and an immediately adjacent lower floor. The poke-through assembly is usually installed with a cover which serves as a cap or lid for the hole. Also, the poke-through generally includes an upper frame or basket designed to create an easily accessible cavity or recess at the surface of the upper floor. Alternatively, such frames or baskets can be used to hold power and/or data receptacles therein. The upper frame is generally metallic and is in direct contact with a cover plate or the upper flooring itself. A lower end of the contemporary poke-through is connected to a junction box accessible to an adjacent lower floor. Intumescent material is generally used between the upper basket and the lower end. Also, the upper and lower portions of the poke-through are secured with a number of metallic bolts, screws or other fasteners that pass through the intervening intumescent material. However, the intumescent material does not provide a stable support structure, especially when heated substantially. Thus, the fasteners provide a more durable coupling for the upper and lower portions of the poke-through.
While the intumescent material acts well as a thermal barrier, the metallic fasteners pass through the thermal barrier and conduct heat to the upper portions of the poke-through. As the heads of the fasteners are generally in direct contact with the metallic upper basket, portions of the adjacent upper flooring can overheat from the conductive heat transfer.
There is therefore a need for a poke-through device that provides improved heat isolation features. Such heat isolation features preferably minimize and/or reduce conductive heat transfer within the poke-through that bypasses the traditional thermal barrier. Such improved heat isolation features must be inexpensive, manufactured easily and quickly installed. Additionally, it would be beneficial if the improved features could be retrofit into existing poke-throughs without replacing the entire assembly.
SUMMARY OF THE INVENTION
One aspect of the present invention provides a poke-through device for installation in a hole in a floor structure. The floor structure is defined by a floor in a first working environment and a ceiling in a second working environment. The poke-through device includes a basket, thermal barrier, lower plate and at least one coupling member. The basket includes a coupling support surface. The thermal barrier is disposed below the basket. Also, the at least one coupling member extends through the thermal barrier and secures the basket to the lower plate. The coupling member includes an upper portion disposed within the basket. The upper portion includes an undersurface, wherein a first portion of the undersurface is in direct contact with the support surface and a second portion of the undersurface does not directly engage the basket.
Another aspect of the present invention includes a poke-through device including a receptacle-receiving basket, an intumescent member, a base member and at least one fastener assembly. The receptacle-receiving basket includes a coupling bracket. The intumescent member is disposed below the basket. The base member supports the intumescent member. Also, the at least one fastener assembly extends through the intumescent member and secures the intumescent member between the basket and the base member. The fastener assembly includes an upper head disposed within the basket, wherein a first portion of the fastener assembly is in direct contact with the coupling bracket and a second portion of the fastener assembly does not directly engage the coupling bracket.
Additionally, the poke-through device of the present invention can have the coupling member include a head on at least one end and a dispersion plate disposed between the head and the support surface. The undersurface of the upper portion can be a downward facing surface of the dispersion plate. The dispersion plate can be formed of a ceramic-fiber washer. Also, coupling support surface can be an upper surface of at least one support member integrally formed with the basket. The support member can protrude upwardly toward the first working environment from a base of the basket. Also, the support member can protrude inwardly from an outer portion of the basket. Further, the support member can include a tab for holding the dispersion plate in a pre-selected position.
Further, the poke-through device can include a second thermal barrier disposed at least partially above the coupling member. The dispersion plate can be an annular washer. Also, the dispersion plate can be sized to conform to at least a portion of an inner peripheral surface of the basket. The basket can include ribs that interlock with the dispersion plate for positioning the dispersion plate.
Further still, the fastener assembly can include a dispersion plate disposed between the head and the coupling bracket. Also, the coupling bracket can include an upper surface for engaging the fastener assembly first portion. The coupling bracket can protrude upwardly toward the first working environment from a base of the basket. Also, the coupling bracket can protrude inwardly from an outer portion of the basket. The coupling bracket can further include a tab for holding the dispersion plate in a pre-selected position. The poke-through device can include an additional intumescent member disposed at least partially above the fastener assembly. Further, the dispersion plate can be an annular member. The basket can include ribs that interlock with the dispersion plate for positioning the dispersion plate.
These and other objects, features, and advantages of this invention will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top perspective assembled view of one embodiment of the poke-through assembly of the present invention with a cover assembly and conduit structures.
FIG. 2 is a top partially exploded perspective view of the poke-through assembly and cover assembly shown in FIG. 1 , without the lower assembly.
FIG. 3 is a top perspective relief view of a stand-off coupling mount shown at A in FIG. 2 .
FIG. 4 a is a top perspective relief view of a stand-off coupling mount assembled with a screw and washer, as shown at B in FIG. 2 .
FIG. 4 b is a top perspective relief view as shown in FIG. 4 a , with an additional washer.
FIG. 5 is a top perspective assembled view of a second embodiment of the poke-through assembly of the present invention with a cover assembly and conduit structures.
FIG. 6 is a top partially exploded perspective view of the poke-through assembly and cover assembly shown in FIG. 5 , without the lower assembly.
FIG. 7 is a top perspective relief view of an alternative stand-off coupling mount shown at A 1 in FIG. 6 .
FIG. 8 is a top perspective view of the lower portions of the poke-through assembly shown in FIG. 6 , assembled with screws and a dispersion ring.
FIG. 9 is a top perspective relief view of the alternative stand-off coupling mount, as shown at B 1 in FIG. 8 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This invention pertains to a poke-through device that provides improved heat isolation features, particularly in the form of a stand-off coupling mount that improves heat isolation. Also, the features of the present invention are relatively inexpensive, manufactured easily and quickly installed. Additionally, the features of the present invention can be retrofit into existing poke throughs without replacing the entire assembly.
FIG. 1 shows a poke-through device 10 with a cover assembly 20 and lower conduit elements 30 secured thereto. As shown, the poke-through preferably includes a basket 100 , a thermal barrier 200 and a lower end plate 300 . Also shown are portions of the stand-off coupling mount 120 and an upper thermal barrier 210 . The exploded view in FIG. 2 shows some additional elements of the assembly in FIG. 1 . In particular, the basket 100 is shown unobstructed with the cover assembly 20 , upper thermal barrier 210 and a coupling member 400 separated there from. Also, more clearly shown in FIG. 2 are two stand-off coupling mounts 120 , preferably secured to a lower portion of the basket 100 . The basket 100 preferably is made to receive one or more receptacles and associated connectors, components and supporting brackets. However, basket 100 can also be configured as a furniture feed, without receptacles, providing access between floors for cabling and/or conduit. While the basket 100 shown forms a cup-like member, with various openings and cutouts, it should be understood that this element could have many variations known in the art. For example, the peripheral side walls of the basket 100 need not be continuous, but preferably cover a substantial portion of the floor hole in which it is installed. Similarly, fewer or additional openings or cutouts could be provided and the basket 100 can have a non-cylindrical shape. Additionally, while the basket 100 can be made of various materials, it is preferably made of die-cast zinc or aluminum.
The poke-through also preferably includes at least one thermal barrier 200 in the form of a fire/smoke retardation or intumescent member. Thermal barrier 200 is bounded on its lower side by lower end plate 300 and on its upper side by the basket 100 . The three components are preferably held together via at least one coupling member 400 as shown. The thermal barrier 200 is configured with a series of passageways therethrough (not shown). Larger and smaller openings pass vertically through the material for passing data, power or other cabling, as is known in the art. At least one of the small openings passing therethrough is occupied by a coupling member shaft 402 . When the poke-through is assembled, preferably an additional upper thermal barrier 210 is contained above the coupling member and within the basket 100 .
The coupling member 400 , shown in FIG. 2 , includes a screw or bolt with a central shaft 402 , an upper head 404 and a lower threaded portion 406 . Preferably a stainless steel screw is used, as such parts are readily available, very durable and relatively heat resistant as compared to other metals. However, it should be understood that although a common screw/bolt is shown in FIG. 2 a more unique fastener could be used for the coupling member 400 . The coupling member 400 also includes a load/heat dispersion plate 420 , that is sized to receive a central shaft 402 of the coupling member 400 and support the upper head 402 .
FIGS. 3 , 4 a and 4 b show more detail, as indicated at A and B in FIG. 2 , of the stand-off coupling mount 120 and its interaction with a coupling member 400 . The coupling mount 120 is preferably located at a lower portion 110 of the basket 100 . The coupling mount 120 includes a central aperture 125 for passage of the shaft 402 . Also, the coupling preferably includes one or more stand-off posts 130 intended to support the coupling member 400 . While the embodiment shown in FIGS. 3 and 4 a show four stand-off posts 130 , it should be understood that greater or fewer posts could be provided so long as the coupling member 400 is supported and sufficient thermal dissipation is provided. The upper portion of the stand-off posts 130 preferably includes a contact surface 132 intended to directly engage an underside or undersurface of an upper portion of the coupling member 400 . Thus, as illustrated in FIGS. 4 a and 4 b , the undersurface of either the dispersion plate 420 in FIG. 4 a or the additional plate or washer 430 in FIG. 4 b directly engage the contact surface 132 . The embodiments shown in FIGS. 3 , 4 a and 4 b further include optional reinforcing and/or stabilizing features for the coupling mount 120 . In particular, the central cylindrical boss 122 , which is either integrally formed with or fixedly attached to the posts 130 provides support for the coupling mount. Also, the extension tabs 138 help position and stabilize the dispersion plate 420 .
Thus, the coupling member shaft 402 passes through an aperture 125 in the basket 100 . The head 404 of the coupling member sits on the dispersion plate 420 , which in turn rests on either the stand-off contact surface 132 ( FIG. 4 a ) or rests on washer 430 ( FIG. 4 b ). In this way, the stand-off posts 130 support the dispersion plate 420 and/or the washer 430 with minimum surface contact between the metallic head 404 and the basket 100 . This is intended to reduce the conductive heat transfer between those elements. In addition to potentially dispersing thermal energy conducted through the shaft 402 and head 404 , the dispersion plate 420 also acts as a load dispersing member, like a traditional washer. Thus, the configuration, shape and materials used for the dispersion plate 420 , as well as the coupling member 400 can prolong the amount of time it will take for the basket 100 to reach its critical temperature or melting point.
Since the poke-through 10 is placed below floor level, the bottom of the coupling shaft 406 reaches the highest temperature during a fire. The long shank of the preferably stainless steel screw 402 transfers heat to the top portion, primarily by conduction, passing through the thermal barrier 200 . Thus, the temperature at the head 404 is transferred (again mainly by conduction) to the supporting structure. In this embodiment, by providing a contact surface 132 with a smaller surface area than the downwardly facing undersurface of the head 404 , heat conduction from the coupling member 400 to the basket 100 is reduced. Additionally, providing additional portions of the coupling member 400 , particularly its undersurface, that do not directly engage either the coupling mount 120 or the basket 100 , promotes convective cooling.
The dispersion plate 420 shown in FIGS. 2 and 4 a , as well as the additional plate 430 shown in FIG. 4 b , are in the form of an annular washer. However, other shapes and sizes for these plates could alternatively be used. It should be understood that while the dispersion plate 420 is shown to be separate from the shaft 402 and/or head 404 , the two elements could be integrally formed or joined together chemically or mechanically. Preferably, the dispersion plate 420 is also stainless steel, however other materials such as ceramics, plastics or heat resistant fibers could be used. The dispersion plate 420 material is preferably selected for its low thermal conductivity, strong durability and/or low cost. Additional washer 430 is preferably a heat resistant material, such as ceramic fiber, and used in combination with a stainless steel dispersion plate 420 .
Preferably the washer 430 provides an additional thermal barrier for the convective heat transfer in the poke-through assembly. Washer 430 is preferably made of a heat resistant material such as a refractory ceramic fiber, for example NUTEC FIBRATEC®, FIBERFAX®, CERWOOL®, KAOWOOL® and others. Such materials can typically be manufactured in a paper or pad form which can be cut into almost any shape, is light weight, relatively inexpensive and particularly suited for this application. For example, such materials can typically withstand temperatures of 2000° F. to 3000° F. and can certainly function well as at least a temporary thermal barrier. By resisting conductive heat transfer directly between the coupling member 400 and the basket 100 , the upper portions of the poke-through 10 will not heat as quickly. The washer 430 can be made up entirely of refractory ceramic fibers or can have a layered configuration such that the ceramic paper is included as one or more of the substrate layers. Alternatively, all or a portion of the washer 430 can include other materials. As a further alternative, portions of washer 430 could either include gaps in the ceramic material or simply be reinforced by separate areas of ceramic material.
FIGS. 5 and 6 show an alternative design for the poke-through devices 11 . As shown, the poke-through 11 preferably includes a basket 101 , a thermal barrier 201 and a lower end plate 301 . Also shown are portions of the alternative stand-off coupling mounts 121 and a modified upper thermal barrier 211 . The exploded view in FIG. 6 shows some additional elements of the assembly in FIG. 5 . In particular, the basket 101 is shown unobstructed with a coupling member 401 separated there from. Also, more clearly shown in FIG. 6 are two alternative stand-off coupling mounts 121 , preferably secured to a lower portion of the basket 101 . While two mounts 121 are shown, it should he understood that additional mounts could be included. Ultimately, the mounts 121 need to support the coupling member 401 , while minimizing contact surfaces. Also shown is an alternative dispersion plate 421 , which is significantly larger than the earlier version. The alternative dispersion plate 421 is sized to accommodate an inner diameter of the basket 101 . In this embodiment the basket 101 is designed with stabilizing features such as protruding ribs that mate with indents on the alternative dispersion plate 421 . Also, the coupling member shaft 403 is made to pass through a notch 422 . It should be understood that the alternative dispersion plate 421 could be made to have a circular aperture, rather than just a notch. Additionally, the same design considerations mentioned above are preferably used when selecting materials for the plate 421 .
FIGS. 7-9 show even further details of the alternative poke-through 11 . In particular, FIG. 7 shows details of an alternative stand-off coupling mount 121 as shown at A 1 in FIG. 6 . The stand-off support structure 131 has a more cylindrical form and is incorporated around a lower structure 111 of the basket 101 . As with the previous embodiment, contact surface 133 is located at the top of the support structure 131 , with notches or gaps 123 in the lower structure 111 creating open spaces to minimize the thermal transfer surfaces and promote convective cooling. FIG. 9 shows details shown at B 1 in FIG. 8 . In particular FIG. 9 shows how plate 421 sits on top of the contact surface 133 and is secured to the coupling member head 403 . As with the first embodiment, this additional embodiment includes heat isolation features that serve to increase the amount of time for the conductive heat transfer process to take place in the support frame while reducing its temperature by convectional cooling in order to help meet regional testing requirements. Also, as with the earlier embodiments, an additional ceramic fiber washer or dispersion plate 430 can be used between dispersion plate 421 and the support structure 131 .
Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be applied therein by one skilled in the art without departing from the scope or spirit of the invention. | A poke-through device for installation in a hole in a floor structure. The floor structure defined by a floor in a first working environment and a ceiling in a second working environment. The poke-through device includes a basket, thermal barrier, lower plate and at least one coupling member. The basket including a coupling support surface. The thermal barrier being disposed below the basket. The lower plate supporting the thermal barrier. Also, the at least one coupling member extending through the thermal barrier and securing the basket to the lower plate. The coupling member including an upper portion disposed within the basket. The upper portion including an undersurface, wherein a first portion of the undersurface is in direct contact with the support surface and a second portion of the undersurface does not directly engage the basket. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of application Ser. No. 10/973,440, filed Oct. 27, 2004, which is based on Japanese priority application No.2004-178442 filed on Jun. 16, 2004, the entire contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention generally relates to semiconductor devices and more particularly to a semiconductor device having polysilicon wiring.
[0003] A CMOS device is a semiconductor device comprising a p-channel MOS transistor and an n-channel MOS transistor formed on a common semiconductor substrate and has a construction in which respective polysilicon gate electrodes are connected with each other.
[0004] With the CMOS device of such a construction, the gate electrode of the p-channel MOS transistor and the gate electrode of the n-channel MOS transistor are formed respectively of p-type and n-type polysilicon having a generally equal work function, and thus, an advantageous feature of the p-channel MOS transistor and the n-channel MOS transistor having generally equal threshold characteristics is attained.
REFERENCES
[0005] (Patent Reference 1) Japanese Laid Open Patent Application 10-12745 official gazette
[0006] (Patent Reference 2) Japanese Laid Open Patent Application 10-74846 official gazette
[0007] (Patent Reference 3) Japanese Laid Open Patent Application 11-26767 official gazette
SUMMARY OF THE INVENTION
[0008] In recent high-speed or ultrahigh speed CMOS devices, the thickness of the gate insulation film is reduced to 2 nm or less according to the scaling low with miniaturization of the p-channel or n-channel MOS transistor constituting the CMOS device.
[0009] In such high-speed or ultrahigh speed CMOS devices, on the other hand, it is practiced to form a low-resistance silicide layer-on the surface of the polysilicon gate electrode and on the surface of the source and drain regions in order to reduce the gate resistance and to reduce the contact resistance of the source and drain regions. It should be noted that such a silicide layer is formed also on the polysilicon pattern connecting the gate electrode of the p-channel MOS transistor and the gate electrode of the n-channel MOS transistor. Generally, such a silicide layer is formed by a so-called salicide process in which a metal film is deposited on the silicon substrate so as to cover the polysilicon gate electrode and the source and the drain regions and silicide is formed by causing the metal film thus deposited to react with the polysilicon pattern constituting the gate electrode and the part of the silicon substrate constituting the source and drain regions.
[0010] FIGS. 1A and 1B show the construction of such a conventional CMOS device 10 , wherein FIG. 1A shows the CMOS device 10 in a plan view while FIG. 1B shows the same device in a cross-sectional view.
[0011] Referring to FIGS. 1A and 1B , the CMOS device 10 is formed on a silicon substrate 11 wherein the silicon substrate 11 is formed with a device region 11 A for the p-channel MOS transistor 10 A and a device region 11 B for the n-channel MOS transistor 10 B separated from each other by a device isolation structure 12 .
[0012] It should be noted that the p-channel MOS transistor 10 A includes a gate electrode 14 A formed on the silicon substrate 11 via a gate insulation film 13 A in the device region 11 A, and a silicide layer 14 a is formed on the gate electrode 14 A. Further, in the device region 11 A, p-type diffusion regions 11 a and 11 b are formed in the silicon substrate 11 at both lateral sides of the gate electrode 14 A, and silicide layers 11 c and 11 d are formed on the respective surfaces of the p-type diffusion regions 11 a and 11 b.
[0013] Similarly, the n-channel MOS transistor 10 B includes, in the device region 11 B, a gate electrode 14 B formed on the silicon substrate 11 via a gate insulation film 13 B, and a silicide layer 14 b is formed on the gate electrode 14 B. Further, in the device region 11 B, there are formed n-type diffusion regions 11 e and 11 f in the silicon substrate 11 at both lateral sides of the gate electrode 14 B, and silicide layers 11 g and 11 h are formed on the respective surfaces of the p-type diffusion regions 11 e and 11 f.
[0014] As can be seen from the plan view of FIG. 1A , the gate electrode 14 A and the gate electrode 14 B are connected with each other by a polysilicon pattern 14 C extending over the device isolation structure 12 , and a silicide layer 14 c is formed on the polysilicon pattern 14 C in continuation with the silicide layers 14 a and 14 b. Thereby, the gate electrode 14 A is doped to the p-type and the gate electrode 14 B is doped to the n-type, while the polysilicon pattern 14 C is undoped except of the parts connected to the gate electrode 14 A and the gate electrode 14 B.
[0015] In the cross-sectional diagram of FIG. 1B , there is further formed an interlayer insulation film 15 on the substrate 11 so as to cover the gate electrodes 14 A and 14 B and further the polysilicon pattern 14 C, and contact plugs 16 A, 16 B, 16 C and 16 D are formed in the interlayer insulation film in contact with the diffusion regions 11 a, 11 b, 11 e and 11 f respectively, via respective silicide layers 11 c, 11 d, 11 g and 11 h.
[0016] In such a CMOS device, on the other hand, there is a need of decreasing the thickness of the gate insulation films 13 A and 13 B in correspondence to the gate length thereof in the case the gate length of the p-channel MOS transistor 10 A or the n-channel MOS transistor 10 B is decreased for improvement of the operational speed. Associated with this, the thickness of the gate electrodes 13 A and 13 B, and hence the height thereof, is reduced, and as a result, there can occur the problem that the metal film deposited at the time of formation of the silicide layer 14 a comes close the gate insulation film 13 A and the metal film deposited at the time of formation of the silicide layer 14 b comes close to the gate insulation film 13 B. In such a case, there can occur diffusion of metal element from the metal film into the gate insulation film 13 A or 13 B, leading to formation of defects in the gate insulation film 13 A or 13 B. Further, associated with such formation of defects in the gate insulation film 13 A or 13 B, there arises a problem of increase of occurrence of so-called B-mode failure in which the lifetime of the semiconductor device is reduced with increase of the gate leakage current.
[0017] In order to avoid such B-mode failure, it is conceivable to reduce the thickness of the metal film deposited at the time of formation of the silicide layer in such a salicide process, while such an approach can lead to localized formation of region 14 x lacking silicide as shown in FIGS. 2A and 2B . In FIGS. 2A and 2B , it should be noted that those parts corresponding to the parts described previously are designated by the same reference numerals and the description thereof will be omitted.
[0018] When such a region 14 x lacking silicide is formed on the polysilicon gate electrode 14 A or 14 B doped heavily to the p-type or n-type and thus having a sheet resistance of several ten Ω/□ or so, the electric current flowing therein avoids such a region 14 x not formed with silicide and flows through the polysilicon pattern constituting the gate electrode 14 A or 14 B. Because of this, no particular problem such as disconnection or remarkable increase of resistance is caused. In the case the region 14 x lacking silicide is formed on the non-doped polysilicon pattern 14 C extending over the device isolation region 12 , on the other hand, there is formed no alternative current path in view of the fact that the polysilicon layer underneath the silicide layer 14 c has a very large sheet resistance of several MΩ/□, and there can be caused a serious problem such as disconnection or increase of resistance.
[0019] Contrary to this, Patent Reference 1 discloses the technology for avoiding the problem of FIGS. 2A and 2B by increasing the thickness of the silicide layer on the non-doped polysilicon pattern as compared with the silicide layer formed on the p-type or n-type pattern, by utilizing the phenomenon that the titanium silicide layer formed by a salicide process takes different thicknesses between the cases in which the silicide layer is formed on a non-doped polysilicon pattern and in which the silicide layer is formed on a doped polysilicon pattern doped to p-type or n-type.
[0020] FIG. 3 shows the construction of the polysilicon pattern according to the foregoing Patent Reference 1.
[0021] Referring to FIG. 3 , there are formed device regions 1 A and 1 B on a silicon substrate 1 by an insulating device isolation film 2 , and a polysilicon pattern 3 is formed on the silicon substrate 1 via a gate insulation film not illustrated, such that the polysilicon pattern 3 extends over the device isolation film 2 from the device region 1 A to the device region 1 B. It should be noted that the polysilicon pattern 3 is doped to the p-type or n-type in the device region 1 A and to the opposite conductivity type in the device region 1 B. On the other hand, the polysilicon pattern 3 is not doped on the device isolation film 2 .
[0022] In the case a titanium silicide film 4 is formed on such a polysilicon pattern 3 by a salicide process, on the other hand, the titanium silicide film 4 is formed with an increased thickness in the region 4 A thereof because of the fact that the polysilicon pattern 3 is not doped on the device isolation film 2 , and it becomes possible to decrease the thickness of the metal titanium film deposited at the time of forming the titanium silicide film by a salicide process.
[0023] However, this conventional technology, utilizing the natural effect of doping of the underlying polysilicon pattern for the formation of silicide, can cause only the thickness change of several ten Angstroms (several nanometers) for the titanium silicide layer 4 in correspondence to the region 4 A. Obviously, the thickness change caused with this magnitude is insufficient at all for avoiding the discontinuity or disconnection of the silicide layer 4 on the device isolation film 2 .
[0024] In a first aspect of the present invention, there is provided a semiconductor device, comprising:
[0025] a substrate having first and second device regions separated from each other by a device isolation region;
[0026] a first field effect transistor having a first polysilicon gate electrode and formed in said first device region;
[0027] a second field effect transistor having a second polysilicon gate electrode and formed in said second device region;
[0028] a polysilicon pattern extending over said device isolation region from said first polysilicon gate electrode to said second polysilicon gate electrode; and
[0029] a silicide layer formed on a surface of said first polysilicon gate electrode, a surface of said second polysilicon gate electrode and a surface of said polysilicon pattern so as to extend on said polysilicon pattern from said first polysilicon gate electrode to said second polysilicon gate electrode,
[0030] said silicide layer having a region of increased film thickness on said polysilicon pattern,
[0031] wherein said silicide layer has a surface protruding upward in said region of increased film thickness.
[0032] In another aspect of the present invention, there is provided a semiconductor device, comprising:
[0033] a substrate having a device region defined by a device isolation region;
[0034] a field effect transistor having a polysilicon gate electrode and formed on said device region;
[0035] a polysilicon pattern extending out from said polysilicon gate electrode and extending over said device isolation region; and
[0036] a silicide layer formed on a surface of said polysilicon gate electrode and on a surface of said polysilicon pattern so as to extend over said polysilicon pattern from said polysilicon gate electrode,
[0037] said silicide layer including a region of increased film thickness on said polysilicon pattern, said silicide layer having a surface protruding upward in said region of increased film thickness.
[0038] Another object of the present invention is to provide a method of fabricating a semiconductor device, comprising the steps of:
[0039] forming, on a substrate including a device region device by a device isolation region, a field effect transistor in corresponding to said device region, such that a polysilicon pattern extends out from a polysilicon gate electrode of said field effect transistor, such that said polysilicon pattern extends over said device isolation region;
[0040] depositing a metal film on said substrate so as to cover said gate electrode and said polysilicon pattern;
[0041] forming a mask pattern on said metal film so as to cover a part of said polysilicon pattern existing on said device isolation region;
etching said metal film while using said mask pattern as a mask so as to reduce a thickness of said metal film in a part thereof not covered with said mask pattern; and
[0043] forming a silicide layer on a surface of said gate electrode and a surface of said polysilicon pattern by applying an annealing process after removing said mask pattern.
[0044] According to the present invention, the thickness of the silicide layer is increased in the polysilicon pattern extending from a polysilicon gate electrode even in the case the silicide layer itself is formed on the polysilicon gate electrode with an extremely small thickness by a salicide process, and it becomes possible to reduce the occurrence of B-mode failure drastically. Further, at the same time, it becomes possible to suppress the occurrence of the problem such as disconnection or increase of the resistance. Thus, according to the present invention, it becomes possible to miniaturize a semiconductor device such as a CMOS device such that the thickness of the gate insulation film of the MOS transistor is reduced to 2 nm or less and such that the gate length is reduced to 130 nm or less.
[0045] According to the present invention, in particular, it becomes possible to suppress the occurrence of the B-mode failure substantially to zero and simultaneously the occurrence of defective operation of the semiconductor device caused by failure of silicide formation also substantially to zero, by setting the thickness of the metal film on the gate electrode to 8 nm or less and by setting the thickness of the metal film on the polysilicon pattern extending out from the gate electrode to 10 nm or more at the time of formation of the silicide layer by a salicide process.
[0046] Other objects and further features of the present invention will become apparent from the following detailed description when read in conjunction with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] FIGS. 1A and 1B are diagrams showing the construction of a conventional CMOS device;
[0048] FIGS. 2A and 2B are diagrams explaining the problems encountered when device miniaturization is made in the conventional CMOS device;
[0049] FIG. 3 is a diagram showing an example of a conventional polysilicon interconnection pattern;
[0050] FIG. 4 is a plan view diagram showing the construction of a CMOS device according to an embodiment of the present invention;
[0051] FIGS. 5A-5J are diagrams showing the fabrication process of the CMOS device of FIG. 4 ;
[0052] FIG. 6 is a diagram showing a part of FIG. 5I in an enlarged scale; and
[0053] FIG. 7 is a diagram showing the relationship between the thickness of the metal film in the salicide process, the occurrence of B-mode failure and the occurrence of defective operations.
DETAILED DESCRIPTION OF THE INVENTION
[0054] FIG. 4 is a diagram showing a schematic construction of a CMOS device 20 according to a first embodiment of the present invention in a plan view.
[0055] Referring to FIG. 4 , the CMOS device comprises a silicon substrate 21 formed with device regions 21 A and 21 B in such a manner that the device regions 21 A and 21 B are isolated from each other by an insulating device isolation film 22 , and a p-channel MOS transistor 20 A having a polysilicon gate electrode 24 A doped to the p-type and an n-channel MOS transistor 20 B having a polysilicon gate electrode 24 B doped to the n-type are formed respectively in the device region 21 A and in the device region 21 B, such that the gate electrodes 24 A and 24 B are connected by a polysilicon pattern 24 C extending over the device isolation film 22 .
[0056] Further, in the construction of FIG. 4 , there is formed a thin cobalt silicide layer 24 a on the polysilicon gate electrode 24 A, and a thin cobalt silicide layer 24 b is formed on the polysilicon gate electrode 24 B. Further, a thin cobalt silicide layer 24 c is formed on the polysilicon pattern 24 C in continuation with the cobalt silicide layer 24 a and the cobalt silicide layer 24 b.
[0057] Further, there are formed silicide layers 24 e and 24 f in the device region 20 A at both lateral sides of the gate electrode 24 A respectively in correspondence to the source region and the drain region of the p-channel MOS transistor 20 A. In the device region 20 B, on the other hand, there are formed silicide layers 24 g and 24 h respectively in correspondence to the source region and the drain region of the n-channel MOS transistor 20 B.
[0058] Further, in the CMOS device 20 of the present embodiment, it should be noted that there is formed a region 24 d of increased thickness in a part of the polysilicon pattern 24 C intermediate to the transistor 20 A and the transistor 20 B such that there occurs an increase of thickness of the silicide layer 24 c in such a region 24 d of increased thickness.
[0059] Hereinafter, the fabrication process of the CMOS device 20 of FIG. 4 will be explained with reference to FIGS. 5A-5J , wherein it should be noted that these drawings represent the cross-sectional diagrams taken along the lines A-A′, C-C′ and B-B′ of the plan view of FIG. 4 .
[0060] Referring to FIG. 5A , the device isolation film 22 forms an STI (shallow trench isolation) structure on the silicon substrate 21 , and gate insulation films 23 A and 23 B are formed in the step of FIG. 5B respectively on the device region 21 A and 21 B by an oxide film or an oxynitride film with a thickness of 2 nm or less.
[0061] In the step of FIG. 5A , it should be noted that there is formed an n-type well (not shown) in the device region 21 A by introducing As+ or P+ with an impurity concentration level of 1×10 13 cm 3 by a ion implantation process. Similarly, there is formed a p-type well (not shown) in the device region 21 B by introducing B+ or BF 2 + with an impurity concentration level of 1×10 13 cm −3 by an ion implantation process.
[0062] Next, in the step of FIG. 5B , a polysilicon film is deposited on the substrate 21 thus formed with the gate insulation films 23 A and 23 B, uniformly with the thickness of about 180 nm, and the gate electrodes 24 A and 24 B are formed respectively in the device regions 21 A and 21 B as a result of patterning of the polysilicon film. Further, as a result of the patterning of the polysilicon film, the polysilicon pattern 24 C is formed on the device isolation film 22 at the same time. In the present embodiment, it should be noted that the polysilicon film is patterned such that the p-channel MOS transistor 20 A and the n-channel MOS transistor 20 B have a gate length of 130 nm or less.
[0063] After the step of FIG. 5B , an ion implantation process of B+ is conducted in the state that the device region 21 B is covered with the resist pattern with an impurity concentration level of 1×10 14 cm −3 while using the gate electrode 24 A as a self-aligned mask, and as a result, there are formed p-type LDD regions 21 a L and 21 b L in the device region 21 A at both lateral sides of the gate electrode 24 A. Further, by conducting an ion implantation process of As+ or P+ into the device region 21 B while using the gate electrode 24 B as a self-aligned mask in the state that the device region 21 A is covered with a resist pattern, there are formed n-type LDD regions 21 c L and 21 d L in the device region 21 B at both lateral sides of the gate electrode 24 B.
[0064] Next, in the step of FIG. 5C , a sidewall insulation film is formed on both sidewall surfaces of the gate electrodes 24 A and 24 B, and a resist pattern R 1 having a resist window exposing the device region 21 A is formed on the substrate 21 . Further, ion implantation process of B+ is conducted into the device region 21 A with an impurity concentration level of 1×10 15 cm −3 while using the resist pattern R 1 as a mask. Thereby, there are formed p-type diffusion regions 21 a and 21 b in a partially overlapping relationship with the p-type LDD regions 21 a L and 21 b L formed previously, as the source region and the drain region of the p-channel MOS transistor 20 A. As a result of the process of FIG. 5C , it should be noted that, although not illustrated, there is formed a similar sidewall insulation film also on both sidewall surfaces of the polysilicon pattern 24 C.
[0065] Next, in the step of FIG. 5D , the resist pattern R 1 is removed and a resist pattern R 2 having a resist window exposing the device region 21 B is formed on the substrate 21 . Further, ion implantation of As+ or P+ is conducted into the device region 21 A with an impurity concentration level of 1×10 15 cm −3 while using the resist pattern R 2 as a mask, and there are formed n-type diffusion regions 21 c and 21 d in a partially overlapping relationship with the n-type LDD regions 21 c L and 21 d L as the source region and drain region of the n-channel MOS transistor 20 B.
[0066] With this ion implantation process of FIGS. 5C and 5D , the part of the polysilicon pattern 24 C close to the gate electrode 24 A is doped to the p-type and the part of the polysilicon pattern 24 C close to the gate electrode 24 B is doped to the n-type. On the other hand, the intermediate part of the polysilicon pattern 24 C is not doped and maintains the undoped state.
[0067] Next, in the step of FIG. 5E , the resist pattern R 2 is removed and a metallic cobalt film 25 is deposited on the substrate 21 by a sputtering process, and the like, uniformly with a thickness of about 10 nm, such that the cobalt film 25 covers the gate electrodes 24 A and 24 B.
[0068] Next, in the step of FIG. 5F , a resist film is formed on the structure of FIG. 5D , wherein the resist film is exposed by using an exposure mask used in the step of FIG. 5C for exposing the resist pattern R 1 . Further, by developing the resist film thus exposed, there is formed a resist pattern R 3 having a resist window R 3 A such that the resist window R 3 A exposes the device region 21 A.
[0069] Next, in the step of FIG. 5G , the same resist pattern R 3 is exposed by using an exposure mask used at the time of exposing the resist pattern R 2 for use in the step of FIG. 5D . After development, there is formed a resist window R 3 B exposing the device region 21 B in the resist pattern R 3 , in addition to the foregoing resist window R 3 A. Further, in the step of FIG. 5G , the metallic cobalt film 25 is etched with a depth of about 2 nm for the part exposed by the resist openings R 3 A and R 3 B while using the resist pattern R 3 as a mask.
[0070] Because there occurs no etching in the metallic cobalt film 25 in this process for the part covered with the resist pattern R 3 , there is formed a structure shown in FIG. 5H when the resist pattern R 3 is removed, wherein it will be noted that there is formed a protruding part in the metallic cobalt film 25 in correspondence to the non-doped part of the polysilicon pattern such that the metallic cobalt film 25 has an increased thickness in the non-doped part. In the step of FIG. 5H , it should be noted that the thickness of the metallic cobalt film 25 thus deposited is reduced to about 8 nm or less in the part covering the gate electrode 24 A or 24 B as a result of the etching conducted while using the resist pattern R 3 as a mask. On the other hand, the metallic cobalt film 25 maintains the initial thickness of 10 nm on the part covering the polysilicon pattern 24 C.
[0071] Thus, by applying an annealing process to the structure of FIG. 5H at the temperature of 850° C., the metallic cobalt film 25 causes a reaction with a silicon surface in the part where such a silicon surface is exposed underneath the metallic cobalt film 25 , and as a result, the silicide layers 21 e and 21 f are formed on the surface of the diffusion regions 21 a and 21 b and the silicide layers 21 g and 21 h are formed on the surface of the diffusion regions 21 c and 21 d. Further, the silicide layers 24 a and 24 b are formed on the gate electrodes 24 A and 24 B and the silicide layer 24 c is formed on the polysilicon pattern 24 C, wherein it will be noted that the silicide layer 24 thus formed includes the region 24 d of increased thickness as shown in FIG. 6 in correspondence to the region 25 A of increased thickness of the cobalt film 25 .
[0072] Referring to FIG. 6 , it should be noted that the silicide layer 24 c formed with such a process has a thickness t 1 smaller than 24 nm on the polysilicon pattern 24 C, while the thick region 24 d of the silicide layer is formed with a thickness t 2 of 30 nm or more. Further, according to the present invention, the thick region 24 d forms a protrusion having a step height A in correspondence to the protrusion 25 A of the metallic cobalt film 25 , wherein it should be noted that the thickness t 1 is equal to the thickness of the silicide film formed on the gate electrode 24 A or 24 B.
[0073] Further, in the step of FIG. 5J , an interlayer insulation film 250 is formed on the structure of FIG. 5I and via-plugs 26 A and 26 B are formed in the interlayer insulation film 250 in contact with the diffusion regions 21 a and 21 b via the silicide layers 21 e and 21 f. Further, in the interlayer insulation film 250 , there are formed via plugs 26 C and 26 D in contact with the diffusion regions 21 c and 21 d via the silicide layers 21 g and 21 h.
[0074] FIG. 7 shows the occurrence of B-mode failure and occurrence of defective operation caused by failure of silicide formation for the CMOS device 10 explained previously with reference to FIGS. 2A and 2B for the case the thickness of the metallic film deposited in the step corresponding to the step of FIG. 5E for the formation of the silicide layer 14 a is changed variously.
[0075] Referring to FIG. 7 , it will be noted that the occurrence of the B-mode failure is decreased when the thickness of the metallic film is decreased, while there occurs an increase in the defective operation caused by the failure of silicide formation explained with reference to FIGS. 2A and 2B with such decrease of thickness of the metallic film. When the metallic film has a large thickness, on the other hand, the defective operation caused by failure of silicide formation is decreased, while it can be seen that there occurs increase of B-mode failure.
[0076] In the present embodiment, the thickness of the metallic cobalt film 25 formed on the gate electrodes 24 A and 24 B is reduced to 8 nm or less in the step of FIG. 8H , and thus, the occurrence of the B-mode failure is reduced substantially to zero. Further, the occurrence of the defective operation of the CMOS device caused by the failure of silicide formation on the polysilicon pattern 24 C is also suppressed with the present invention to substantially zero by setting the thickness of the cobalt film in the region 25 A of increased thickness to 10 nm or more.
[0077] In the process of the Patent Reference 1 in which the titanium film is formed uniformly with the thickness of 300 Angstroms (30 nm) for the silicide formation reaction, on the other hand, formation of the B-mode failure is not suppressed in the case the process of the reference is applied to ultrafine semiconductor devices in which the thickness of the gate electrode is reduced.
[0078] While the foregoing embodiment has been explained for the case of formation of a cobalt silicide film, the present invention is not limited to such a specific material but is applicable also to the formation of other silicide films including a titanium silicide film, a nickel silicide film, a tungsten silicide film, a molybdenum silicide film, a zirconium silicide film, and the like.
[0079] In the present invention, there is formed a step in the metal film deposited for the silicide formation by conducting a patterning process prior to the silicide formation reaction, and thus, it becomes possible to secure a large difference of film thickness in the silicide layer between the region 24 d of increased thickness and the region other than the foregoing region 24 d, and thus, it becomes possible to secure a sufficient film thickness for the silicide layer formed on the polysilicon pattern 24 C while simultaneously minimizing the thickness of the silicide layer on the gate electrodes 24 A and 24 B.
[0080] In relation to this, it should be noted that the present invention is particularly useful in the ultrafine semiconductor devices having a gate length of 130 nm or less and the thickness of the gate insulation film is 2 nm or less.
[0081] Further, it should be noted that the present invention is not limited to a CMOS device but also to semiconductor device in general as long as there is formed an extension of a polysilicon pattern from the polysilicon gate electrode of the p-channel MOS transistor or the n-channel MOS transistor.
[0082] Further, the present invention is not limited to the embodiments explained heretofore, but various variations and modifications may be made without deporting from the scope of the invention. | A semiconductor device includes a substrate having first and second device regions separated from each other by a device isolation region, a first field effect transistor having a first polysilicon gate electrode and formed in the first device region, a second field effect transistor having a second polysilicon gate electrode and formed in the second device region, a polysilicon pattern extending over the device isolation region from the first polysilicon gate electrode to the second polysilicon gate electrode, and a silicide layer formed on a surface of the first polysilicon gate electrode, a surface of said the polysilicon gate electrode and a surface of the polysilicon pattern so as to extend on the polysilicon pattern from the first polysilicon gate electrode to the second polysilicon gate electrode, the silicide layer having a region of increased film thickness on the polysilicon pattern, wherein the silicide layer has a surface protruding upward in the region of increased film thickness. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 13/305,358 filed Nov. 28, 2011, which is a continuation of International Patent Application No. PCT/EP2009/056690 filed May 29, 2009, the contents of which are hereby incorporated by reference.
BACKGROUND
[0002] The present application relates to devices for injecting, delivering, administering, infusing or dispensing a substance, and to methods of making and using such devices. More particularly, it relates to an injection device for administering a product, e.g. a drug. In some embodiments, it relates to automatic injection devices, although it is not limited to such devices.
[0003] Automatic injection devices, which may be referred to as auto-injectors, are known from the prior art. Such devices provide for automatic delivery of a substance or product. A needle associated with such devices can be injected manually or automatically. If the needle is manually injected or inserted into a patients or users body, the injection movement of the needle is imparted by a user's hand, for example by the user grasping the injection device and pressing it onto an injection point, thus injecting the needle. If the needle is automatically injected, the injection movement of the needle is generated by a drive member, such as a spring element, which advances the needle into the injection point.
[0004] Such injection devices can comprise an opening from which the needle can be extended manually or automatically. There are devices in which the opening exhibits a diameter only slightly larger than the needle, such that accessing the needle, for example with a finger, and thus inadvertently pricking oneself is prevented. In these devices, however, the ability to assemble the injection device may be affected or restricted. There are also devices in which the opening is dimensioned large enough to facilitate assembly of the device, but in these devicess, the opening is generally large enough that a finger can fit into or through it, thus incurring the danger of an inadvertant needle stick or pricking.
[0005] Injection devices which accommodate a product or substance container, e.g. an ampoule, carpoule, vial, etc., containing a product to be delivered are also known. A needle can be attached to the distal end of the product container. In some instances, the proximal end of the product container, i.e. the end opposite the needle, is fastened to the injection device. Due to the forces which arise when an injection device is used, the product container may be released and/or separated from the injection device or, in more extreme cases, the container may break, thus enabling it to fall out of the injection device.
SUMMARY
[0006] An object of the present invention is to provide an injection device in which the danger of an inadvertant needle stick or pricking is reduced or eliminated, yet the injection device remains convenient to assemble. (Any reference to “the invention” or “the present invention” in this application shall not be construed as a generalization, limitation or characterization of any subject matter disclosed herein and shall not be considered to be an element or limitation of the appended claims except if and/or where explicitly recited in a claim(s). Another object of the present invention to provide an injection device in which the product container is prevented from falling out of the device.
[0007] In one embodiment, an injection device in accordance with the present invention comprises a distal end, a needle located inside the injection device in an initial position, wherein the needle is moveable to a puncturing position in which the needle projects or extends from the distal end of the device, an opening region relative to the needle in the initial position of the needle and having a dimension, and a reduction piece moveable relative to the opening region whereby the dimension may be reduced. In some embodiments, the opening region is located distally relative to the needle in the initial position of the needle.
[0008] In some embodiments, the present invention relates to an injection device for administering a product, e.g. a liquid or fluid product or substance such as a medicinal or therapeutic substance. The product or substance can be stored in a product container in liquid form or in liquid and solid form. In the latter case, the product container may be referred to and/or thought of as a bicameral or multi-chambered product container in which a liquid active agent is mixed with a solid or powdery active agent directly before administering. The injection device can be designed for manual or automatic injecting. In some preferred embodiments, the injection device is an automatice device, which may be referred to and/or thought of as an auto-injector.
[0009] In one aspect of the present invention, the injection device comprises a distal end and a needle, wherein the needle is situated within the injection device in an initial position or condition and can be moved to an injection position in which it protrudes or extends beyond the distal end of the injection device. The needle is situated in its initial position in the injection device as sold, shipped or otherwise provided to a user. In the injection position, the needle protrudes beyond the distal end of the injection device to an extent which approximately corresponds to the injection depth of the needle into and/or through the skin at the injection point. The distal end of the injection device is designed to be pressed onto and/or around the injection point. The needle can be fixedly connected to the product container, such as when the product container is manufactured. In this embodiment, the product container can also be referred to as a syringe and its proximal end can comprise a flange by which the syringe can be fastened in the injection device. Alternatively, the needle can be fastened, as a separate part, to the product container. The product container may be referred to as a carpoule or ampoule. The proximal end of the carpoule, ampoule and syringe may, but need not necessarily, comprise a flange for fastening, which is sometimes referred to as a finger flange.
[0010] In some embodiments, an injection device in accordance with the present invention comprises an opening region which is situated distally with respect to the needle and/or the needle tip, when the needle is in its initial position, wherein the opening region exhibits a dimension, e.g. a cross-section. When the needle is in its initial position, the opening region can extend between the needle and/or needle tip and the distal end of the injection device. The needle tip is to be understood to mean the distal end region of the needle. The opening region can be surrounded laterally, i.e. around the longitudinal axis of the needle, by a housing or a triggering element, e.g. in the shape of a sleeve. The opening region can exhibit a cross-section, i.e. a cross-sectional area, which is approximately normal to the longitudinal axis of the needle. The cross-section is delineated by the structure or structural element(s) which immediately surrounds the cross-section. The opening region may exhibit a constant or a varying cross-section over its overall axial length. If an opening region comprises a number of cross-sections of different areas, it should be understood that, in some embodiments, it is the smallest cross-section that is being referred to when a cross-section is mentioned.
[0011] In some embodiments, an injection device in accordance with the present invention comprises a movable reducing piece. The reducing piece can be moved into the opening region, e.g. from a position which does not lie in the opening region. The movement may be directed along the longitudinal axis, e.g. parallel to the longitudinal axis, transverse to the longitudinal axis, or transverse to and along the longitudinal axis in combination. The movement of the reducing piece into the opening region reduces the cross-section of the opening region. The reducing piece can reduce the cross-section of the opening region at the point at which it is arranged in the opening or open region. The reducing piece may comprise an opening which exhibits a cross-section smaller than the cross-section of the opening region at the point at which the reducing piece is arranged in the opening region. The cross-section of the opening region in the region of the reducing piece may be dimensioned such that the needle can be moved through the opening region despite the reducing piece arranged in the opening region.
[0012] Structure, features and function in accordance with the present invention reduce the size of the opening or open region such that accessing the needle through the opening, for example with a finger, is no longer possible. This reduces the danger of inadvertant sticks or pricking, as well as reduces the chance of contaminating the needle.
[0013] In some preferred embodiments, an injection device in accordance with the present invention comprises a removing element, e.g. in the form of a cap, which is removably arranged on the injection device, e.g. on its distal end. The removing element prevents access to the needle in the injection device as sold or dispatched. After the removing element is removed from the device, access to the opening region is enabled, yet the opening region is constrictable by the reducing piece, such that access into the opening region up to the needle is not possible.
[0014] In some preferred embodiments, the reducing piece can be moved into the opening region from a position in the injection device, e.g. proximally with respect to the needle tip. The product container accommodated in the injection device may comprise a portion which serves to accommodate the product to be administered, wherein the reducing piece can be moved into the opening region from a position which lies axially in the region of the portion for accommodating the product to be administered. The product container comprises a piston which can be moved in the portion for accommodating the product to be administered, e.g. from a proximal position to a distal position. This movement displaces the product and delivers it through the needle. The portion for accommodating the product to be administered lies proximally with respect to the portion to which the needle can be or is fastened.
[0015] In some embodiments, the reducing piece may surround the product container partially, e.g. in segments, and in some preferred embodiments it surrounds the container annularly, for example in the region of the portion to which the needle is fastened. The reducing piece may form or comprise a passage for the product container.
[0016] In some preferred embodiments, the product container can be provided with a needle protecting cap in the injection device as dispatched, wherein the needle protecting cap is arranged on the portion to which the needle is fastened. The needle protecting cap protects the needle against contamination and keeps it sterile. The product container may be inserted into the injection device as a complete module together with the needle protecting cap. The needle protecting cap may be made of a flexible material, such as a rubber-like material, or a firm material such as hard plastic. The latter embodiment may be referred to as a so-called rigid needle shield. When the removing element and the needle protecting cap are removed, the needle is exposed in the opening region of the injection device, wherein the reducing piece can nonetheless prevent anyone pricking themselves.
[0017] In some preferred embodiments, the reducing piece can be fixed in a position in the opening region, such as in a force fit and/or positive fit. An example of a force-fit connection would be clamping the reducing piece in the opening region. An example of a positive-fit connection would be a latching connection in which the reducing piece or a part of the reducing piece latches into an element which surrounds the reducing piece. To this end, in some embodiments the reducing piece can comprise cams or snappers which are elastically biased and latch into the element surrounding the reducing piece at the desired axial position in the opening region. The part which surrounds the reducing piece can comprise one or more recesses into which the reducing piece latches. The part which surrounds the reducing piece can be a housing, a triggering element or a needle protecting sleeve.
[0018] In some preferred embodiments, the opening of the reducing piece exhibits a smaller cross-section than the opening region of the injection device and a larger cross-section than a needle protecting cap arranged on the product container and/or a portion for accommodating the product to be administered. This means that during assembly, at least the needle protecting cap of the product container—and, in other embodiments, the portion for accommodating the product to be administered—can be inserted through the opening of the reducing piece.
[0019] In some preferred embodiments, the reducing piece can be moved relative to a housing, a needle protecting sleeve, a triggering element and/or the needle. In some embodiments, the needle protecting sleeve can be moved over the needle situated in the injection position to cover the needle again after use. The reducing piece is slaved in the movement of the needle protecting sleeve, e.g. when the reducing piece has been connected axially fixed to the needle protecting sleeve. The triggering element serves to trigger the movement of the needle from its initial position into its injection position. The triggering element can release an energy storage means which shifts the needle, in some embodiments together with the product container. In some preferred embodiments, the needle protecting sleeve can simultaneously perform the function of the triggering element. The needle protecting sleeve which serves as the triggering element can be shifted in the proximal direction relative to the housing, for example by pressing the distal end of the needle protecting sleeve onto the injection point. The needle protecting sleeve or the triggering element can protrude distally beyond the distal end of the housing, wherein when the injection device is pressed onto the injection point, the needle protecting sleeve or the triggering element is moved proximally into the housing. After the injection device has been used, the needle protecting sleeve can protrude beyond the distal end of the housing to an extent which is greater than the extent to which the needle protecting sleeve protrudes beyond the distal end of the housing before the injection is triggered.
[0020] Another aspect of the present invention, which can be both pursued in its own right and/or combined with other embodiments of the present invention, relates to an injection device for administering a product which comprises a product container for accommodating the product to be administered. The product container comprises a tapering region or portion which connects distally to a portion for accommodating the product. This portion can be embodied to be hollow-cylindrical and/or can shiftably accommodate a piston which can displace the product from the product container. The piston can be moved through the whole of the portion for accommodating the product. The proximal end of the product container can comprise a projection which extends outwardly, e.g. radially, such as a flange.
[0021] In some embodiments, a fastening portion for the needle can connect or be arranged distally with respect to the tapering region of the product container. The fastening portion can be embodied such that a needle can be attached to the product container and/or detached again from the product container. In some embodiments, the needle is fixedly arranged on the fastening portion.
[0022] In some embodiments, the needle is exposed at least immediately before administering. In the product container and/or injection device as sold and/or dispatched, the needle can be surrounded by the needle protecting cap which is fastened to the fastening portion for the needle, e.g. in a force fit and/or positive fit, e.g. by being fitted on and/or by a frictional fit. The needle protecting cap can be able to be completely or at least partially removed from the product container to expose the needle. The needle protecting cap can be a so-called rigid needle shield or a simple rubber cap. In the case of a rigid needle shield, it may be possible to remove only a part of the needle protecting cap to expose the needle, wherein another part of the rigid needle shield remains on the product container, e.g. on the fastening portion. The remaining part and removable part of the rigid needle shield can be connected by a material-fit or positive-fit connection, e.g. with a predetermined breaking point, which can be released by being destroyed.
[0023] In some embodiments, an injection device in accordance with the present invention comprises a movable holding member which can be moved from a position in which it does not fulfil a holding function for the product container to position in which it does fulfil a holding function for the product container. In some preferred embodiments, the holding member may be moved distally to in front of a tapering region and/or a collar of the product container. The holding member can contact the product container in the position in which it fulfils the holding function, but need not, such that a gap can exist between the tapering region and the holding member as measured in the axial direction. If the holding member contacts the product container, it can serve to divert a force exerted on the product container by removing the needle covering cap. If a gap exists between the holding member and the tapering region, the holding member can serve to prevent the product container from falling out of the injection device if the fastening device with which the product container is normally accommodated in the injection device fails. The fastening device can be embodied by a flange arranged on the proximal end of the product container and/or abutting the proximal end of a product container holder. If the flange should for whatever reason break, the holding member prevents the container from falling out of the injection device.
[0024] In some embodiments, the holding member can be shifted from a first position into the holding position. In the first position, the holding member can be situated laterally with respect to the product container, e.g. the portion for accommodating the product. In the first position, the holding member can be arranged such that the tapering region of the product container can be guided past the holding member. In some preferred embodiments, the holding member can be guided at least in portions along the portion for accommodating a product.
[0025] In some embodiments, when moving into the holding position, the holding member can be able to perform a radial movement in relation to the longitudinal axis of the product container. To this end, the holding member as a whole or in part can perform a radial movement. The holding member can be deformed, e.g. partially deformed, when it is moved into the holding position. The deformation can be elastic and/or plastic. In some embodiments, the holding member can be pivoted toward the longitudinal axis.
[0026] In some preferred embodiments, an injection device in accordance with the present invention comprises a means by which the holding member can perform a combined axial and radial movement when moving to the holding position. Such a means can, for example, be a part of a gear system, a gear surface, a guiding rail, etc. For example, a gear surface can be provided which forces the holding member toward the longitudinal axis of the product container during its axial movement. The gear surface can force the holding member, e.g. shift and/or pivot and/or deform it, at least partially or completely into the holding position.
[0027] In some embodiments, the means for deflecting the holding member, e.g. the gear surface, can be arranged or formed on an element which surrounds the product container. This element may be a product container holder. The product container holder can form a passage for the product container; e.g. it can be sleeve-shaped and surround the product container. The holding member is arranged, e.g. radially, between the product container and the product container holder. The product container holder can thus surround both the holding member and the product container. The holding member can be arranged such that it can be moved relative to the product container and/or product container holder when moving into the holding position. The product container holder, the holding member, the product container and the housing of the injection device can, for example, be arranged concentrically with respect to each other.
[0028] In some embodiments, the distal end of the product container holder can comprise an opening which allows a part of the product container to be inserted through it. The opening is large enough that the product container, together with a needle protecting cap attached to it, can be inserted through it. The opening can, but need not, be large enough that the portion for accommodating the product to be administered would fit through the opening. The means for deflecting the holding member is arranged on the distal end of the product container holder which is formed over the circumference of the product container holder. The means for deflecting can comprise a surface which is inclined with respect to the longitudinal axis.
[0029] In some embodiments, the holding member can surround the product container over its circumference. The holding member can comprise a number of tongues which can be moved to in front of the tapering region of the product container by material deformation. In some preferred embodiments, the tongues can be meant when a holding member which can be moved to in front of the tapering region of the product container is mentioned. This means that not all of the holding member but merely a part of the holding member need be able to be moved to in front of the tapering region. The holding member can comprise an annular base from which the at least one tongue extends, e.g. in the direction of the longitudinal axis.
[0030] In some embodiments, in the position in front of the tapering region of the product container, the holding member is or can be latched against moving any further relative to the product container. To this end, the at least one tongue or the annular base or another part of the holding member can comprise a latching element which engages with the part surrounding the latching element, e.g. with the product container holder. The latching element of the tongue can engage with the deflecting means for the holding member and/or tongue.
[0031] In some embodiments, an injection device in accordance with the present invention can comprise at least one engaging member which is coupled in a force fit and/or positive fit to at least one of the reducing piece and the holding member, thus enabling the reducing piece and/or holding member to be slaved in an axial movement of the at least one engaging member. In some preferred embodiments, the at least one engaging member can be moved in the distal direction. It can slave the engaging member, at least in portions, in this movement. To this end, the engaging member can comprise links which extend from the annular base, e.g. in the longitudinal direction and in the same direction as the at least one tongue. In some preferred embodiments, the at least one engaging member can be moved in the distal direction and slaves the holding member, at least in portions, in this movement, wherein no relative movement is performed between the holding member and the at least one engaging member in the course of slaving. To this end, the at least one engaging member can engage with the at least one link of the holding member. The holding member and the at least one engaging member can be moved together until the engaging member is moved in front of the product container. It is possible for the at least one engaging member to move further relative to the holding member.
[0032] In some embodiments, when the holding member is moved, the reducing piece can be moved along with it by being supported on the holding member. Alternatively or additionally, the reducing piece can be moved along with the at least one engaging member, for example by the engaging member engaging with it. In some preferred embodiments, the needle protecting cap can be removed from the product container when the at least one engaging member is moved in the distal direction, wherein this can be performed before, after or while the reducing piece and/or holding member is slaved.
[0033] In some embodiments, the at least one engaging member can be formed on a removing element, e.g. a cap, on one or more arms which extend in the longitudinal direction and mount the at least one engaging member, spring-elastically transverse to the longitudinal axis. The following steps can thus be performed when the removing element is removed from the injection device:
removing the needle protecting cap; and/or slaving the holding member, such that its tongues are moved to in front of the collar of the product container; and/or slaving the reducing piece into a position in which it reduces the cross-section of the opening region and thus prevents access to the needle.
[0037] In some embodiments, an injection device in accordance with the present invention can comprise at least one of the following features:
a needle protecting sleeve which serves as a triggering element for triggering an injection movement of a needle, wherein the needle protecting sleeve can be shifted in the proximal direction relative to the housing of the injection device to trigger the injection movement and can be shifted in the distal direction over the needle situated in the injection position; an elasticity means, e.g. a spring, against which the triggering element can be shifted for triggering and with which the triggering element can be shifted in the distal direction over the needle situated in the injection position; a driven member which can be shifted in the distal direction by a drive member, e.g. an advancing spring, to shift the product container for an injection movement of the needle and/or to move a piston in the product container for delivering product; a blocking member which can be selectively engaged with the driven member or the triggering element to prevent an axial movement of the part with which the blocking member is engaged.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] FIG. 1 depicts two sub-assemblies of an embodiment of an injection device in accordance with the present invention, before their final assembly;
[0043] FIG. 2 a depicts individual parts of the injection device, in a perspective view;
[0044] FIG. 2 b is an enlarged view of three parts of the view from FIG. 2 a;
[0045] FIG. 2 c is an arrangement of the three parts from FIG. 2 b , as shipped or sold;
[0046] FIGS. 3 a and 3 b are longitudinal sectional views of an injection device with a removing element attached, wherein FIG. 3 b is a view rotated by 90° about the longitudinal axis in relation to FIG. 3 a;
[0047] FIGS. 4 a and 4 b are longitudinal sectional views of the injection device, from which the removing element has been removed, in an initial state, wherein FIG. 4 b is a view rotated by 90° about the longitudinal axis in relation to FIG. 4 a;
[0048] FIGS. 5 a and 5 b are longitudinal sectional views of the injection device when triggered, wherein FIG. 5 b is a view rotated by 90° about the longitudinal axis in relation to FIG. 5 a;
[0049] FIGS. 6 a and 6 b are longitudinal sectional views of the injection device in a state after an injection sequence and before a delivery sequence, wherein FIG. 6 b is a view rotated by 90° about the longitudinal axis in relation to FIG. 6 a;
[0050] FIGS. 7 a and 7 b are longitudinal sectional views of an injection device after a delivery sequence, wherein FIG. 7 b is a view rotated by 90° about the longitudinal axis in relation to FIG. 7 a ; and
[0051] FIGS. 8 a and 8 b are longitudinal sectional views of an injection device comprising a needle protecting sleeve in a needle protecting position, wherein FIG. 8 b is a view rotated by 90° about the longitudinal axis in relation to FIG. 8 a.
DETAILED DESCRIPTION
[0052] With regard to fastening, mounting, attaching or connecting components of the present invention, unless specifically described as otherwise, conventional mechanical fasteners and methods may be used. Other appropriate fastening or attachment methods include adhesives, welding and soldering, the latter particularly with regard to the electrical system of the invention, if any. In embodiments with electrical features or components, suitable electrical components and circuitry, wires, wireless components, chips, boards, microprocessors, inputs, outputs, displays, control components, etc. may be used. Generally, unless otherwise indicated, the materials for making embodiments of the invention and/or components thereof may be selected from appropriate materials such as metal, metallic alloys, ceramics, plastics, etc. Unless otherwise indicated specifically or by context, positional terms (e.g., up, down, front, rear, distal, proximal, etc.) are descriptive not limiting. Same reference numbers are used to denote same parts or components.
[0053] The individual parts of an injection device, which specifically form an auto-injector, shall firstly be described with reference to FIGS. 2 a to 2 c . In the depicted embodiment, the injection device comprises: a sleeve-shaped housing 1 ; a needle protecting sleeve 2 accommodated in the housing 1 such that it can be longitudinally shifted and simultaneously serves as a triggering element; a product container 5 with a needle protecting cap 6 detachably fastened to it; a product container holder 4 which accommodates the product container 5 and comprises deflecting structure or means 4 a ; a removing element 3 which comprises engaging members 3 a , 3 d ; a drive member 8 in the form of a helical spring which acts as a pressure spring and supplies the energy for injection and delivery sequences; a driven member 7 which acts on the product container 5 ; a holding element 10 which keeps the drive member 8 tensed until the injection device is triggered and which is connected axially fixed to the housing 1 , snapped onto the housing 1 ; and a spring element 9 which supplies the energy for shifting the needle protecting sleeve 2 to the needle protecting position. The injection device also comprises a holding member 12 which allows easy assembly and can nonetheless prevent the product container from falling out of the injection device, and a reducing piece 11 which serves as an access protection to prevent anyone sticking or pricking themselves on the device. Of preferred embodiments, the one shown here includes both the holding member 12 and the reducing piece 11 . In principle, the injection device can be fitted with only one of these two parts.
[0054] FIG. 1 shows an auto-injector before its final assembly. When finally assembled, the auto-injector is provided in two sub-assemblies, namely a sub-assembly A which comprises the housing, the needle protecting sleeve 2 and the drive unit, already biased, and a sub-assembly B which comprises the product container 5 , the product container holder 4 , the removing element 3 and at least one of the holding member 12 and the reducing piece 11 . This division into sub-assemblies has the advantage that the sub-assemblies can be pre-assembled at a location other than the location at which the product container is finally assembled and/or integrated. The sub-assembly A and the sub-assembly B minus the product container can, for example, be supplied from a first facility to a second facility, wherein at the second facility, the product container 5 together with the needle protecting cap 6 is inserted with the needle protecting cap 6 first into the product container holder 4 of a combination of the product container holder 4 and the removing element 3 via an opening on the proximal end of the product container holder 4 . The holding member 12 and the reducing piece 11 respectively comprise an opening (which may be thought of and/or referred to as comprising elements 11 d , 12 d ) which is large enough to insert the needle protecting cap 6 of the product container 5 through. The holding member 12 and the reducing piece 11 are respectively arranged in first positions and respectively shifted into second positions only once the removing element 3 is removed from the injection device. This enables the product container 5 including the needle protecting cap 6 to be easily integrated into the rest of the parts of the sub-assembly B.
[0055] The completely assembled sub-assembly B can then be inserted into the sub-assembly A via an opening on the distal end of the triggering element 2 , where it is fastened to the housing 1 , axially fixed but detachably, by a fastening member 4 b of the product container holder 4 which in this example is formed as a snapper. Another advantage of the division into sub-assemblies is that a multitude of sub-assemblies A and B can be supplied from the first facility to the second facility, and at the second facility is a decision made as to which drug the injection device is to be fitted with. This increases the ability of the injection device to be flexibly used.
[0056] FIGS. 3 a and 3 b show the completely assembled injection device as sold and/or shipped or dispatched. Reference is additionally made to the representation of the individual parts in FIGS. 2 a to 2 c . The product container 5 is shiftably mounted in the housing 1 . The product container 5 is accommodated in the product container holder 4 such that it cannot be moved in the distal direction relative to the product container holder 4 . This is achieved by a finger flange 5 d which is formed on the proximal end of the product container 5 and protrudes radially outwardly and acts on the proximal facing side of the product container holder 4 . The reservoir part 5 a of the product container 5 accommodates the product to be administered. A piston 5 f is accommodated in the hollow-cylindrical reservoir part 5 a and abuts the inner wall of the reservoir part 5 a , forming a seal, and can be shifted in the direction of the needle 5 e relative to the reservoir part 5 a for delivering product. The needle 5 e is non-detachably fastened to a fastening portion 5 c of the product container 5 . The fastening portion 5 c connects distally to the reservoir part 5 a . The reservoir part 5 a transitions into the fastening portion by a collar 5 b . The collar 5 b thus forms a tapering region, at or in front of which at least a part of the holding member 12 is subsequently moved. To protect the needle 5 e against contamination and to keep it sterile, the needle protecting cap 6 is arranged on the fastening portion 5 c and over the needle 5 e . The needle protecting cap 6 is fastened to the fastening portion 5 c of the product container 5 in a force fit and/or positive fit. Between the collar 5 b of the product container 5 and the proximal end and/or proximal facing side of the needle protecting cap 6 there exists a gap which is at least large enough that at least one or both of the engaging members 3 a , 3 d and a part of the holding member 12 can engage with the gap.
[0057] The holding member 12 and the reducing piece 11 are shown in detail in FIGS. 2 b and 2 c . The reducing piece 11 comprises an annular base 11 c . The annular base 11 c comprises a passage or opening 11 d which is dimensioned such that the needle protecting cap 6 can be inserted and/or moved through it, at least partially or completely. Conversely, the opening 11 d is dimensioned such that a human finger does not fit through it. The cross-section of the opening 11 d is smaller than the cross-section of the opening region 13 ( FIG. 3 a ), wherein the cross-section of the opening region is reduced by arranging the reducing piece 11 in the opening region 13 . The annular base 11 c also comprises cavities 11 a which are formed laterally with respect to the opening 11 d as passages. The cavities 11 a can be separate from the opening 11 d or—as shown here—connected to the opening 11 d . Each of the cavities 11 a serves as a passage for an arm 3 b which is formed on the at least one engaging member 3 a , 3 d.
[0058] The reducing piece 11 comprises a number of projections which extend in the proximal direction from the annular base 11 c and form abutments or latching elements 11 e , 11 f for the same or different purposes. To this end, the projections can be formed with equal or different lengths.
[0059] The latching element 11 e can, but need not, serve to abut the holding member 12 , e.g. its annular base 12 c . The abutment means that when the holding member 12 is moved in the distal direction, the reducing piece 11 is slaved by the holding member 12 . If the latching element 11 e does not serve as an abutment, the reducing piece 11 can be slaved by the at least one engaging member 3 a , 3 d.
[0060] The latching elements 11 e , 11 f latch, axially fixed, onto the needle protecting sleeve 2 when the reducing piece 11 is situated in its second position, i.e. in the opening region 13 . The reducing piece 11 is slaved in the movements of the needle protecting sleeve 2 due to it latching, axially fixed, onto the needle protecting sleeve 2 . In the example shown, the reducing piece 11 comprises two latching elements 11 e and two latching elements 11 f , wherein the latching elements 11 e are formed on projections which are longer than the projections on which the latching elements 11 f are formed. The latching elements 11 e can serve to block the axial movement in the distal direction, and the latching elements 11 f can serve to block the movement of the reducing piece 11 relative to the needle protecting sleeve 2 in the proximal direction. This means, as may be preferred, that the reducing piece 11 is connected to the needle protecting sleeve 2 such that it cannot be moved in either axial direction relative to the needle protecting sleeve 2 .
[0061] The holding member 12 comprises an annular base 12 c from which tongues 12 a and links 12 e project in the distal direction. The tongues 12 a can be deformed or bent toward the central or longitudinal axis of the holding member 12 flexibly, e.g. elastically or plastically. The tongues 12 a i comprise a latching member 12 b on each of their distal ends, which can subsequently latch onto the deflecting means 4 a.
[0062] Each of the links 12 e comprises a groove 12 f which extends in the longitudinal direction. The grooves serve to provide an engagement for engaging members 3 a or alternatively 3 d of the removing element 3 . The grooves 12 f are continuous but could also be blind grooves. The arms 3 b grip through the cavities 11 a of the reducing piece 11 , such that the at least one engaging member 3 a can engage with the groove 12 f.
[0063] The annular base 12 c forms a passage or opening 12 d which is large enough that the needle protecting cap 6 can be inserted or moved through it. When not deformed, the latching members 12 b do not block the passage for the needle protecting cap 6 .
[0064] The deflecting means 4 a is arranged spring-elastically on the product container holder 4 , e.g. by an arm 4 g . This arrangement may facilitate assembly. As can be seen from FIG. 1 , the product container 5 is inserted into the product container holder 4 which is exposed in the circumferential direction. Since the product container holder 4 is exposed in the circumferential direction before the final assembly, the deflecting means 4 a can spring away outwardlys and thus let the needle protecting cap 6 through, without an increased assembly force being necessary or there being a danger of clamping. Because the cross-section is latterly reduced by the holding member 12 , it is however possible that the deflecting means 4 a do not need to spring away, since the passage for the needle protecting cap 6 is initially large enough. The deflecting means does not therefore necessarily need to be arranged spring-elastically but can also be arranged rigidly. When the injection device is finally assembled, as shown for example in FIGS. 3 a and 3 b , the deflecting means 4 a cannot spring outwardly, since the product container holder 4 is surrounded by the needle protecting sleeve 2 , wherein the inner side of the needle protecting sleeve 2 forms a holding portion 2 c which prevents the deflecting means 4 a from moving radially outward.
[0065] The product container holder 4 comprises a fastening member 4 b , in the form of a cavity, which is directed outward, wherein the fastening member 4 b engages with a projection 1 a formed on the inner circumference of the housing and thus forms a positive-fit lock. This lock can however be released while using the injection device. The lock means that the product container holder 4 is coupled, axially fixed, to the housing 1 , such that the product container 5 also cannot be moved in the distal direction relative to the product container holder 4 due to the engagement of the finger flange 5 d onto the proximal facing side of the product container holder 4 .
[0066] The needle protecting sleeve 2 is guided on the inner circumference of the housing 1 . The needle protecting sleeve 2 is situated radially between the product container holder 4 and the housing 1 . The needle protecting sleeve 2 can in principle be shifted relative to the housing 1 , wherein in the injection device as dispatched, the needle protecting sleeve 2 is axially fixed relative to the housing 1 . To this end, the needle protecting sleeve 2 comprises an engaging member 2 a which engages in a positive fit with an engaging counter member 1 b on the inner side of the housing 1 . The engaging member 2 a is spring-elastically mounted and can be moved transverse to the longitudinal axis of the injection device. The spring-elastic arrangement is formed by an arm, at the end of which the engaging member 2 a is formed.
[0067] The removing element 3 at least partially seals the distal end of the injection device. In some embodiments, the removing element 3 prevents access to the needle protecting sleeve 2 which protrudes beyond the distal end of the housing 1 . The removing element 3 is fastened to the housing 1 in a force fit, by a sleeve-like continuation which surrounds the distal end of the housing 1 . Alternatively or additionally, the removing element 3 can be fastened in a positive fit to the distal end of the injection device, such as for example to the housing 1 or the needle protecting sleeve 2 or via the engagement between the engaging member 3 a and the product container holder 4 , e.g. its cavity 4 f . The removing element 3 also comprises a sleeve-shaped holding portion 3 c which in the injection device as dispatched is situated on the inner circumference of the needle protecting sleeve 2 , axially level with the engaging member 2 a , to prevent the engaging member 2 a from moving inwardly, and thus ensures that the needle protecting sleeve 2 is prevented from moving relative to the housing 1 in the injection device as shipped, i.e. with the removing element 3 attached. It is thus possible to reliably prevent the needle protecting sleeve 2 from being moved relative to the housing 1 , such as for example when the injection device is dropped and the needle protecting sleeve 2 would be moved relative to the housing 1 due to mass inertia. The engaging member 2 a thus serves to provide secure transport. The removing element 3 forms an annular gap between the outer sleeve which is fastened to the circumference of the housing 1 and the inner sleeve which comprises the holding portion 3 c . When the removing element is attached, a part of the housing 1 and a part of the needle protecting sleeve 2 are situated in the annular gap, also the engaging member 2 a and the engaging counter member 1 b formed by the housing. The holding portion 3 c , e.g. its proximal end, also forms an assembly aid for pre-assembling the sub-assembly B, for example in that the reducing piece 11 , e.g. the annular base 11 c , can be supported on the proximal end of the removing element 3 and/or the holding portion 3 c , and at least one of the holding member 12 and the product container holder 4 can optionally be supported on the reducing piece 11 .
[0068] At least one engaging member 3 a , 3 d is formed on the removing element 3 and can be spring-elastically moved transverse to the longitudinal axis of the injection device via the arm 3 b . While the sub-assembly B is pre-assembled, and also in the injection device as dispatched, the cavity 4 f formed on the product container holder 4 is situated level with the engaging member 3 a in the longitudinal direction, such that the engaging member 3 a can spring radially outwardly into the cavity. When the product container 5 is inserted into the combination of the product container holder 4 and the removing element 3 while the sub-assembly B is assembled ( FIG. 1 ), the engaging member 3 a springs into the cavity 4 f when the needle protecting cap 6 passes the engaging member 3 a . The engaging member 3 a also springs into the cavity 4 f when the product container 5 is completely inserted into the product container holder 4 , since in this case, the engaging member 3 a abuts the distal end region and laterally abuts the reservoir part 5 a of the product container 5 . Alternatively, the engaging member 3 a or another engaging member 3 d can engage with the gap between the needle protecting cap 6 and the collar 5 b in this state. The engaging member 3 a protrudes radially outward in relation to the outer circumference of the sleeve-shaped portion forming the holding portion 3 c and thus forms a gear surface, the function of which is described below.
[0069] The engaging member 3 d protrudes inwardly in relation to the inner circumference of the sleeve-shaped portion forming the holding portion 3 c and is hook-shaped and dimensioned such that it can engage with the gap between the needle protecting cap 6 and the collar 5 b in the course of using the injection device.
[0070] Since the engaging members 3 a , 3 d are arranged on approximately the same axial position in the embodiments shown, they can form a common engaging member. In principle, the engaging members 3 a and 3 d can be arranged on different axial positions.
[0071] The removing element 3 also comprises a projection which is directed radially outwardly and makes it easier for the user of the injection device to grip the removing element 3 and apply an axial force to it.
[0072] When the product container 5 is completely inserted into the product container holder 4 , the projection 5 d can abut the proximal end of the product container holder 4 in the longitudinal direction.
[0073] The proximal end of the spring element 9 is supported on the holding element 10 and thus axially fixed with respect to the housing 1 , and its distal end 9 is supported on the proximal end of the needle protecting sleeve 2 . The spring element 9 is biased and charges the needle protecting sleeve 2 with a force which acts in the distal direction, wherein the needle protecting sleeve 2 is blocked against moving in the distal direction both in the initial position and immediately after the removing element 3 is removed ( FIGS. 4 a and 4 b ).
[0074] The holding element 10 seals the proximal end of the housing 1 and is connected to the housing 1 , e.g. snapped onto it, such that it is axially and rotationally fixed. The holding element 10 could equally be formed integrally with the housing 1 , wherein it is advantageous to configure the holding element 10 and the housing 1 in a number of parts, since this facilitates the ability of the individual parts to be manufactured and facilitates assembling the injection device.
[0075] The holding element 10 comprises at least one—in this example, two—spring-elastic arms 10 b which extend in the longitudinal direction of the injection device and form a blocking member 10 a at their distal ends. The blocking member 10 a can be moved transverse to the longitudinal axis of the injection device. The blocking member 10 a forms an inwardly directed projection and an outwardly directed projection in relation to the arm 10 b . The inwardly directed projection engages in a positive fit onto with a collar 7 b formed by the driven member 7 and thus prevents the driven member 7 from being moved in the distal direction. The outwardly directed projection of the blocking member 10 a abuts an inwardly pointing surface of the needle protecting sleeve 2 , such that the blocking member is held in engagement with the collar 7 b and prevented from moving radially outward. The proximal ends of the arms 10 b are formed on a sleeve-shaped portion of the holding element 10 .
[0076] The arm 10 b extends together with the sleeve-shaped portion of the holding element 10 over the entire length of a sleeve-shaped portion of the driven member 7 . The arm 10 b , including the blocking member 10 a and the sleeve-shaped portion, is longer than the sleeve-shaped portion of the driven member 7 . The drive member 8 is accommodated within the sleeve-shaped portion of the driven member 7 in the form of a biased helical pressure spring. The proximal end of the spring element 8 is supported on the holding element 10 , and the distal end of the spring element 8 is supported on the distal end of the sleeve-shaped portion of the driven member 7 , which simultaneously forms the collar 7 b . Two arms which expand in the shape of a fork project from the distal end of the sleeve-shaped portion of the driven member 7 and respectively form a contact element 7 a at their distal end. The contact elements 7 a comprise bevelled surfaces which are flush with the housing wall of the reservoir part 5 a of the product container 5 in the longitudinal direction. This means that the bevelled surfaces of the contact elements 7 a enter into abutment with the proximal end of the product container 5 when the driven member 7 moves in the distal direction.
[0077] In the following, the function or operation of an embodiment of an injection device in accordance with the present invention is described. Starting from the injection device as dispatched, as shown in FIGS. 3 a and 3 b , the user of the device grasps the housing 1 with one hand and the removing element 3 with the other hand. To remove the removing element 3 , the user pulls on the removing element 3 , thus removing it from the housing 1 . When the removing element 3 is removed, the engaging members 3 d are in or enter the gap between the needle protecting cap 6 and the collar 5 b and ultimately enter into abutment with the proximal facing side of the needle protecting cap 6 . The engaging members 3 a are also moved out of the cavities 4 f when the removing element 3 is removed, but remain in the grooves 12 f . The engaging members 3 a , 3 d are ultimately prevented from moving radially outward by the inner side 4 c of the product container holder 4 , wherein the engaging members 3 d are even forced into the engagement with the gap and/or facing side of the needle protecting cap 6 . To this end, the engaging member 3 a which points radially outward forms a gear surface which slides off on the product container holder 4 when the engaging member 3 a moves out of the cavity 4 f and thus, with the aid of the holding portion formed by the inner side of the product container holder 4 , ensures an engagement between the engaging member 3 d and the needle protecting cap 6 . When the removing movement of the removing element 3 is continued, the engaging members 3 d slave the needle protecting cap 6 , thus removing it from the product container 5 , and the engaging member 3 a latches out of the link 12 e or the groove 12 f , since the inward supporting effect for the engaging member 3 a has been removed. The external force which is introduced into the product container 5 by the removing movement can be diverted from the collars 5 b of the product container 5 onto the product container holder 4 via the deformed tongues 12 a and from the product container holder 4 into the housing 1 via the engagement 4 b . Alternatively or additionally, the external force can be diverted from the finger flange 5 d onto the product container holder 4 and from there into the housing 1 via the engagement 4 b . In the first alternative, the projection 5 d of the product container 5 remains unstressed, thus avoiding damage to the product container 5 . When the removing movement of the removing element 3 is continued, the engaging member 3 a which has latched out of the groove 12 f acts on the annular base 11 c and slaves the reducing piece 11 . Removing the removing element 3 also enables the engaging member 2 a of the needle protecting sleeve 2 to move inwards, since removing the removing element 3 also removes the holding portion 3 c.
[0078] The engagement between the engaging member 3 d and the needle protecting cap 6 additionally ensures that the engaging member 3 a remains in the grooves 12 f . In the removing movement of the removing element 3 , the engaging member 3 a abuts against the distal end of the groove 12 f . The holding member 12 is slaved by the removing element 3 . Due to the abutment between the latching element 11 e and the holding member 12 , the reducing piece 11 is also slaved out of its first position which it assumes in the completely assembled injection device. When the holding member 12 is slaved and/or moved in the distal direction, the tongue 12 a is deflected and/or deformed toward the longitudinal axis by the deflecting means 4 a . The deformed tongue 12 a is then situated in front of the collar 5 b , between the needle protecting cap 6 and the collar 5 b . The deformed tongue 12 a latches onto the latching member 12 b which projects radially outward from the tongue 12 a , onto the deflecting means 4 a or onto the product container holder 4 . The holding member 12 is thus axially fixed relative to the product container holder 4 .
[0079] The latching elements 11 e and 11 f of the reducing piece 11 , which is slaved by the removing element 3 with the aid of the holding member 12 and/or the engaging member 3 a , latches—axially fixed—onto the needle protecting sleeve 2 , as shown for example in FIGS. 4 a and 4 b.
[0080] FIGS. 4 a and 4 b show the injection device from which the removing element 3 has been removed. The device is then ready for use. To this end, the user of the device grasps the housing 1 and presses the distal end of the injection device, which is formed by the needle protecting sleeve 2 , onto the injection point. This slides the engaging member 2 a out of the engagement with the engaging counter member 1 b of the housing 1 , such that the engaging member 2 a is deflected inwardly. A relative movement is performed between the needle protecting sleeve 2 and the rest of the injection device, in which the needle protecting sleeve 2 is pushed over a gear surface 4 e of the product container holder 4 which is embodied in the shape of a ramp, thus releasing the engagement between the product container 4 and the projection 1 a of the housing 1 , by deflecting the fastening member 4 b inward. When the needle protecting sleeve 2 is shifted, the spring element 9 is also tensed by the shifting distance and a cavity 2 d which is formed by the needle protecting sleeve 2 is moved so as to be axially level with the blocking member 10 a . Inserting the needle protecting sleeve 2 triggers the injection sequence and by extension also the delivery sequence. The needle protecting sleeve 2 can thus also be referred to as the triggering element 2 .
[0081] FIGS. 5 a and 5 b show the injection device in a state in which the needle protecting sleeve 2 has been inserted for triggering. The fastening member 4 b is out of engagement with the engaging counter member 1 a , thus enabling it to move axially relative to the housing 1 .
[0082] The blocking member 10 a can then be deflected into the cavity 2 d , wherein when it is in engagement with the needle protecting sleeve 2 , it blocks or prevents a movement of the needle protecting sleeve 2 in the distal direction. At the same time as it moves into the cavity 2 d , the blocking member 10 a releases the collar 7 b , such that the biased drive member 8 can move the driven member 7 in the distal direction. The subsequently described part of an overall movement is referred to as the injection sequence. In this movement, the contact elements 7 a enter into abutment with the proximal end of the product container 5 , thus shifting it in the distal direction until the needle 5 e protrudes through the opening 11 d beyond the distal end of the injection device in accordance with the desired injection depth, as shown in FIGS. 6 a and 6 b . As soon as the needle 5 e protrudes out of the distal end of the injection device by the corresponding extent, a second fastening member 4 d which is formed by the product container holder 4 abuts the projection 1 a of the housing 1 , thus stopping the advancing movement of the needle 5 e . The injection sequence is then complete.
[0083] Due to the bevelled surfaces of the contact elements 7 a and the force of the drive member 8 which continues to act, the contact elements 7 a slide off on the proximal end of the product container 5 , such that they are deflected inwardly toward each other and/or into the reservoir portion 5 a , and thus enter into abutment with the piston 5 f . This starts the delivery sequence, since the force of the drive member 8 shifts the piston 5 f in the direction of the needle 5 e , such that the substance or product contained in the product container 5 is delivered via the needle 5 e.
[0084] FIGS. 7 a and 7 b show the injection device at the end of the product or substance delivery sequence, with the contact elements 7 a deflected into the reservoir part 5 a.
[0085] During the injection and delivery sequence, the sleeve-shaped portion of the driven member 7 prevents the blocking members 10 a from passing out of the engagement with the cavities 2 d of the triggering element 2 . At the end of the product delivery sequence, the blocking members 10 a can be moved out of the engagement with the cavity 2 d , since the driven member 7 has been moved completely past the blocking members 10 a.
[0086] Once the user removes the injection device from the injection point a few seconds after the product delivery sequence is complete, the spring element 9 presses the needle protecting sleeve 2 in the distal direction, wherein the blocking members 10 a are moved out of the engagement with the cavities 2 d . The needle protecting sleeve 2 is also shifted over the distal end of the needle 5 e together with the reducing piece 11 , as shown in FIGS. 8 a and 8 b.
[0087] To prevent the needle protecting sleeve 2 from being pushed back into the housing 1 , the needle protecting sleeve 2 comprises a blocking member 2 c which engages with the projection 1 c of the housing 1 in a positive fit, e.g. such that it cannot be released, and/or such that it can only be released by extreme force and/or by being destroyed. It is thus no longer possible under normal circumstances to push the needle protecting sleeve 2 back into the housing 1 . It is also not possible to insert a finger into the distal end of the injection device due to the size or dimension, e.g. cross-section, of the opening region 13 being reduced by the reducing piece 11 . The danger of injury as a result of using the device is thus reduced.
[0088] Embodiments of the present invention, including preferred embodiments, have been presented for the purpose of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms and steps disclosed. The embodiments were chosen and described to illustrate the principles of the invention and the practical application thereof, and to enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth they are fairly, legally, and equitably entitled. | An injection device having a distal end, and including a needle located inside the injection device in an initial position, wherein the needle is moveable to a puncturing position in which the needle projects from the distal end, an open region located distally relative to the needle in the initial position of the needle and having a dimension, a reduction piece moveable relative to the opening region whereby the dimension may be reduced and a holding member that latchingly connects to the reduction piece and a product container holder. | 0 |
This invention relates to a technique for drilling straight bore holes in the earth and more particularly to a stabilizer assembly and a method of making and using the same.
BACKGROUND OF THE INVENTION
As discussed at some length in U.S. Pat. No. 4,874,045, the art of drilling bore holes in the earth has evolved substantially. Initially, a bit was simply threaded onto the end of drill pipe and the resultant bore hole meandered significantly into the earth, typically in a corkscrew manner. At the present time, an attempt to drill a relatively straight vertical bore hole in the earth incorporates an elaborate bottom hole assembly including a series of stabilizers above the bit and a long length of drill collars above and interspersed between stabilizers.
It has become more desirable to drill straight vertical bore holes in the earth as wells are being drilled deeper. This is because of increased friction generated between rotating drill pipe and the bore hole. One can easily visualize that rotating drill pipe from the surface in a 20000′ well consumes considerably more horsepower than in a 5000′ well. Even where wells are drilled with a mud motor, drill pipe is also preferably rotated from the surface in order to increase the rate of penetration. Unduly meandering bore holes, and the friction generated thereby, are accordingly a much greater problem as well depths increase.
Disclosures of interest relative to this invention are found in U.S. Pat. Nos. 3,250,578; 3,938,853; 4,874,045; 5,474,143 and 5,697,460.
SUMMARY OF THE INVENTION
In this invention, a stabilizer is at least 12′ and preferably us at least about 14′ long and ideally is at least about 16′ long and includes a tube and at least three stabilizing sections integral with the tube. The stabilizer is very well balanced, meaning that rotation of the stabilizer during drilling creates very small lateral forces on the stabilizer and therefore causes very little eccentric motion, or whip, of the stabilizer during rotation.
The stabilizer is balanced mainly by making the inner and outer diameters very concentric to the tube centerline. This is accomplished by providing a cylindrical axial passage that is on the centerline of the tube, subject to very close tolerances, and a cylindrical exterior surface between the stabilizing sections that has been ground or machined to be concentric, subject to very close tolerances, to the tube centerline. Because of the small tolerances of the interior and exterior of the stabilizer, the wall thickness of the stabilizer is very consistent so the stabilizer is very well balanced, meaning there is very little whip or eccentricity during rotation.
The stabilizing sections are integral with the tube or cylindrical part of the stabilizer. This is accomplished by removing material from the blank after the axial passage has been bored. Flutes are then machined in the stabilizer sections to form ribs integral with the tube, by which is meant that the ribs are not welded or secured by fasteners to the body of the tube. The outer diameter of the ribs is somewhat less than the desired finished outer diameter to allow hardbanding followed by grinding or machining of the outer diameter to bring it to tolerance.
It is exceedingly difficult to make a long stabilizer with integral stabilizing sections to very close tolerances. It will be understood that a long stabilizer is stiffer and thus less likely to create a meandering bore hole than two short stabilizers coupled by a threaded connection. The reason, of course, is that no threaded connection is as stiff as unmachined stock of the same inner and outer diameters. All stabilizers currently manufactured for the drilling of hydrocarbon wells have maximum lengths approaching 8½′. The reason is that the grinding machines used to dress the external diameter have 8½′ centers, meaning that longer stock cannot be chucked into the machine. It is almost beyond comprehension to understand how difficult it is to find and acquire, on a basis that makes economic sense, a grinding machine or face plate lathe having 12′ or 16′ centers. Such equipment is massive, prohibitively expensive when new, and awkward to ship and install. Only an obsessive attention to detail would overcome the difficulties.
Seemingly, the main goal of this invention is to drill straight holes. This is not correct because drilling straight holes at unduly slow speeds is not acceptable to the industry because the total cost of drilling a well is directly proportional to the time it takes to drill it. Thus, the main goal of this invention is to drill straight holes at high rates of penetration.
It is an object of this invention to provide an improved method and apparatus for drilling a straight vertical bore hole in the earth.
A further object of this invention is to provide an improved stabilizer for use in a bottom hole assembly.
A more specific object of this invention is to provide a one piece stabilizer that is much longer than conventional stabilizers for use in drilling bore holes in the earth.
These and other objects and advantages of this invention will become more apparent as this description proceeds, reference being made to the accompanying drawings and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a stabilizer of this invention coupled to a bit for drilling a bore hole in the earth;
FIG. 2 is an enlarged cross-sectional view of the stabilizer of FIG. 1 , taken substantially along line 2 - 2 thereof through a stabilizer section, as viewed in the direction indicated by the arrows; and
FIG. 3 is an enlarged cross-sectional view of the stabilizer of FIG. 1 , taken substantially along line 3 - 3 thereof through the tube, as viewed in the direction indicated by the arrows.
DETAILED DESCRIPTION
Referring to FIGS. 1-3 , there is illustrated a drilling assembly 10 comprising a bit 12 and a bottom hole or stabilizer assembly 14 . The bit 12 may be of any suitable type such as a cone-roller bearing type, a conventional diamond bit or a polycrystalline insert type. The stabilizer assembly 14 is made of one piece of metal and comprises a central tube 16 having a threaded female connection or box 18 at one end into which the bit 12 is threaded and another threaded female connection or box 20 at the other end for connection to a drill collar joint (not shown), another stabilizer (not shown) or other oil field tubular. At least three stabilizer sections 22 are located on the exterior of the tube 16 and are separated by cylindrical sections 24 . The stabilizer sections 22 are of a larger outer diameter than the tube 16 and preferably provide helical ribs 26 and flutes 28 for swirling drilling mud as it passes upwardly away from the bit 12 . A fishing neck 30 at the upper end of the stabilizer assembly 14 allows a washover pipe to pass over the top of the assembly 14 if it becomes detached or is shot off in a well.
The tube 16 provides a central passage 32 that is as concentric as reasonably possible relative to a centerline 34 . The purpose of the concentric central passage 30 is to reduce the amount of lateral motion, or whip, when the stabilizer assembly 14 is rotated during drilling. One way of measuring the concentricity of the passage 32 is by measuring the wall thickness 36 , 36 ′, 36 ″, 36 ″′ of the tube 16 in a plane at various radial locations around the centerline 34 and comparing the measurements, as suggested in FIG. 3 . In this invention, the measured wall thicknesses of the tube 16 will not vary by more than 0.050″ and, preferably, the wall thickness of the tube 16 does not vary by more than 0.025″ and, ideally, the wall thickness of the tube 16 does not vary by more than 0.010″. This is not easy to do in a stabilizer assembly that is 8½′ long and is a complicated and difficult problem in a stabilizer assembly 12′ long or longer. Centrally located passages 28 may be drilled to such tolerances by firms such as Boring Specialities of Houston, Tex.
After the metal blank is bored to provide the central passage 28 , metal is removed from the blank in the area of the cylindrical sections 24 by machining on a face plate lathe or by grinding on a grinding machine. This is accomplished by advancing the cone shaped centers of the grinding machine toward each other until they touch, or nearly touch, to determine that their centerlines are aligned. Then, the centers are retracted until they are further apart than the blank to be worked upon. The blank, having the passage therethrough that is centered as nearly as possible, is placed in the face plate lathe or grinding machine so the cone shaped centers enter the passage and thereby center the blank on the machine. The cylindrical sections 24 are then ground, or machined, to remove any eccentricity so the blank is much better balanced than is provided simply by having a bored passage nearly on the blank centerline. After these steps, the wall thickness of the blank, between the inner and outer diameters, as taken in a common plane typically varies no more than 0.005″ and is usually less than 0.002″.
Because the stabilizer assembly 14 is at least 12′ long, preferably at least 14′ long, and ideally about 16′ long, a grinding machine or face plate lathe must be large enough to receive a metal piece of this length. Grinding machines or face plate lathes of this size are not easy to find in any machine shop environment, are expensive when new and are awkward to transport and install. At the present time, there are no grinding machines or face plate lathes available in machine shops catering to the oil service industry to accomplish the desired grinding or machining of the stabilizer sections 22 in a stabilizer assembly of the length of the present invention.
After the cylindrical sections 24 have been formed, the stabilizer sections 22 remaining on the tube 16 are machined to form the flutes 28 . This is done in a conventional manner, i.e. by rotating the blank slightly as it moves past the cutting implements.
The exterior surface of the ribs 26 are initially slightly smaller than the desired outer diameter of the stabilizer sections 22 . Hardbanding 38 is applied to the ribs 26 in a conventional manner, typically by electric arc welding of rods or wire including tungsten carbide particles so that the tungsten carbide particles are embedded in the hardbanding 38 . The thickness of the hardbanding 38 is sufficient to make the ribs 26 larger than the desired outer diameter. The stabilizer assembly 10 is then placed in a grinding machine or face plate lathe having centers sufficiently far apart to accept the assembly 10 and the surface of the stabilizer sections 24 ground or machined to remove enough hardbanding 38 to make the stabilizer sections 22 of the desired diameter. Prototypes of this invention have been made using a cylindrical grinder known as a Norton Model D Landis 36″×192″ S.N. 15684 that was last used as a grinder for drive shafts of submarines and other large marine vessels. At some time in the process of manufacture, the female threads 18 , 20 are machined into the ends of the blank.
As explained in U.S. Pat. No. 4,874,045, it is desirable to match the outside diameter of the bit 12 with the outside diameter of the stabilizer 14 so that the bit 12 is only slightly larger than the stabilizer assembly 14 . By either grinding the exterior of the bit 12 or by grinding the exterior of the stabilizer assembly 14 , the bit 12 ends up being 0.003-0.045 inches larger than the outside diameter of the stabilizer assembly 14 .
By making the stabilizer 10 of greater length, it is stiffer than a comparable joint of stabilizers threaded together. By making the stabilizer 10 balanced about its centerline, there is much less wobble or lateral motion of the stabilizer. Both modifications promote drilling of straight holes.
Although this invention has been disclosed and described in its preferred forms with a certain degree of particularity, it is understood that the present disclosure of the preferred forms is only by way of example and that numerous changes in the details of operation and in the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed. | A stabilizer assembly is at least 12′ long and preferably at least 14′ long and is used to drill a straight bore hole in the earth. A central passage through the assembly closely follows a centerline as may be determined by measuring the wall thickness of the tube at a variety of locations in a single plane. At least three stabilizing sections are integral with the tube and include alternating ribs and flutes. Hardbanding on the ribs is ground down to tolerances with a grinding machine or face plate lathe having centers sufficient to receive the 12′ long stabilizer assembly. | 4 |
SUMMARY OF THE INVENTION
[0001] The invention takes advantage of the ability of neural, network and statistical software to analyse complex patterns generated using arrays of discrete sensing elements with intermediate affinities and specificities (broad specificity) as a strategy for complex sample discrimination. Discrete sensing elements with appropriate affinities and specificities are chosen such that each element in the array has an acceptable signal to noise ratio. The informational content obtained from this assay strategy would be meaningless if analysed using conventional methods, i.e. positive vs negative type analysis. Accordingly, a pattern recognition based data analysis procedure is employed using, but not limited to, neural network and statistical software must be developed and/or adapted must be employed in order to be able to discriminate complex samples. Pattern recognition forms the basis for the discrimination process that takes full advantage of the increased informational content of this diagnostic strategy.
[0002] Thus, instead of quantitating the exact amount of a known compound that has bound to a specific sensing element (as is the case in conventional diagnostics), the bound material is quantitated by determining the increase in thickness or mass on the surface of the sensor. This can be accomplished using a number of nonlabel detection principles including, but not limited to, quartz crystal microbalances, optical techniques such as optoaucostics, reflectometry, ellipsometry and surface plasmon resonance (SPR). An essential aspect of the strategy is the fact that the constituents bound to the sensing elements need not be identified to perform the assay. This makes it possible to use recognition elements with complex interactions such as those found in nature. The samples are discriminated by correlating the values from the entire array using pattern recognition and compared to a reference sample. This increases the speed and reduces the time required to perform assays, thereby reducing costs all of which are objects of this invention.
[0003] In one embodiment of the invention, arrays of lectins are used in combination with neural network analysis as a diagnostic tool to discriminate complex samples, such as serum samples. Lectins are immobilized onto discrete areas in an array onto planar gold coated surfaces using empirically developed high density immobilization protocols. This embodiment of the invention takes advantage of the ability of lectins to recognize saccharides, oligosaccharides and other as yet unknown ligands both natural and synthetic which have an affinity for lectins, free or attached to proteins (glycoproteins), lipids (glycolipids) and other biomolecules. The ubiquitous presence of carbohydrates in all living organisms provides a nearly universal means for identification of complex biological samples. The complex biosynthetic pathways used to synthesize these carbohydrates are effected by subtle changes in their environment. These changes lead to a series of complex global modifications in the composition and thereby the structure of the carbohydrates.
[0004] This invention takes advantage of this diversity in order to increase the amount of information that can be obtained, instead of quantitating the exact amount of a particular compound that has bound to a specific lectin as is routinely done in conventional diagnostics. The use of arrays of lectins enables the identification of global changes in complex samples, thereby allowing discrimination. We assume many different substances with a wide range of affinities for a particular sensing element are competing for the recognition sites on the lectins. An additional object of the invention is the ability of the assay strategy to take advantage of as yet unidentified recognition capabilities present on biomolecules. These unidentified recognition elements will provide information that allow the discrimination of samples with unprecedented accuracy and presently not possible with any other diagnostic assay strategy. This complex interplay provides a wealth of data which, due to the rapid development in computer technology and signal processing techniques, can be rapidly analysed. Moreover, the ability of sensing element arrays will grow dramatically as more biomolecules are tested in the assay and their unknown recognition functions become evident.
[0005] An application of this invention involves the use of lectin arrays to discriminate sera from different animal species. In these studies, the constituent(s) bound to each lectin in the array is quantitated using a fixed angle ellipsometer. The responses obtained from these experiments were used to train the artificial neural network. Using appropriate normalization methods, the resulting trained network was able to discriminate all of the serum samples. The assay shows the utility of the invention for the general identification of complex biological material. Another application of the lectin affinity array was for the discrimination of “healthy” and “sick” individuals (humans). These experiments show, that even subtle changes in serum composition such as those associated with mild bacterial infections can be identified (using artificial neural networks with appropriate normalization). In these experiments, the substance(s) bound to the lectins were quantitated using the SPR detection principle. This shows that sample discrimination is not dependent upon a particular nonlabel technique but is universally applicable to any detector that is capable of unloosing substances bound to the sensing elements in nonlabel modes.
BACKGROUND OF THE INVENTION
[0006] Chemical sensor arrays can be used to identify and classify complex gas mixtures or odors (Shurmer, H. V., An electronic nose: A sensitive and discriminating substitute for a mammalian olfactory system, IEEE proc. G 137, 197-204, 1990; Gardner, J. W. and Bartlett, P. N. (eds), Sensors and Sensory Systems for an Electronic Nose, Proc. NATO Advances Research Workshop, Reykjavik, 1992.). Chemical sensors are in general non-specific, but have different selectivity patterns towards the species in the odor. More specifically, it has been demonstrated how large sensing surfaces consisting of different catalytic metals in metal-oxide-semiconductor field effect structures can be used together with an optical evaluation technique to obtain visually identifiable images of odors (I. Lundström, R. Erlandsson, U. Frykman, E. Hedborg, A. Spetz, H. Sundgren, S. Welin, and F. Winquist, Artificial ‘olfactory’ images from a chemical sensor using a light-pulse technique Nature, 352, 47-50, 1991. It is important to note that this increased informational content is derived from the (continuous) varying selectivity profile along the sensing surface for the sensor array. No discrete recognition elements are known to exist. Different pattern recognition methods based on statistical approaches or artificial neural networks can be used to evaluate the signal patterns from these sensors. The devices have been used to analyze a variety of food stuffs (Winquist, F., Hörnsten, E. G., Sundgren, H. and Lundström, I., Performance of an electronic nose for quality estimation of ground meat, Meas. Sci. Technol. 4, 1493-1500, 1993.; Winquist, F., Hörnsten, G., Holmberg, M., Nilsson, L. And Lundström, I. Classification of bacteria using a simplified sensor array and neural nets”, submitted).
[0007] New sensor concept. The analogy between these sensors and that of biological sensing systems, such as the olfactory system, has been conceptually important in driving the development of this technology. The basis for the human olfactory sense is that a signal pattern is generated from the receptors cells in the olfactory bulb. The receptor cells are not specific for a particular molecules, but rather belong to different selectivity classes. The basis for olfaction (smell) appears to combine the signals obtained from each of the low specificity receptor classes. The combinatorial effect that results leads to an increase in the discriminatory ability of the system (despite the relatively small number of receptor classes). The chemical sensing elements can recognize odors but lack the discrete recognition capabilities that biomolecules and synthetic biomimetic molecules possess. As noted, chemical sensors use continuous gradients and other approaches as recognition elements and are not discrete. Nature uses discrete identifiable sensing elements which have evolved recognition capabilities in a biological context. One object of the invention is to apply discrete biosensing elements in a fashion that increases the informational content of the diagnostic assay. This would require the employment of a biomolecule with broad recognition characteristics which would normally be considered too ill-defined to be useful in conventional diagnostics. The specificity must be chosen so as to obtain adequately broad binding (high informational content) but not so much as to make differentiation between specific and nonspecific binding impossible, i.e. adequate signal to noise ratio. At the same time, biological sensing elements must have well defined binding characteristics that are appropriate for this assay strategy.
[0008] The invention described here involves the development of a new assay strategy for complex sample discrimination using arrays of biorecognition elements that is far more informationally rich than conventional assays. Another object of this invention is to reduce the number of tests that must be performed before a diagnosis can be made, thereby reducing the time required to start treatment as well as the cost. Unlike standard diagnostic tests which detect known compounds highly specifically, we detect the binding of unknown compounds to the lectins. Thus, the new assay strategy requires the employment of specialized nonlabel-based detection techniques, including but not limited to quartz crystal microbalances and optical techniques such as optoaucostics, reflectometry, ellipsometry and surface plasmon resonance (SPR). All of the methods that are based on polarized light reflected off a solid surface have already proven valuable for thickness determination of proteins on solid surfaces. The sensitivity of the methods are about the same, which is on the order of a few ångströms.
[0009] Biological sensing elements. Proteins have the ability to combine specifically and reversibly with a variety of ligands. Enzymes for example bind substrates and inhibitors while antibodies can be produced which bind a variety of antigens such as carbohydrates, proteins, and small molecules. Another class of proteins, lectins, have the ability to bind sugars and are devoid of enzymatic activity. Receptors bind a wide range of ligands with high affinity and specificity. Nature evolves and maintains proteins for specific purposes with adequate affinity and specificity for a particular purpose. Thus, the employment of biological or synthetic biomimetic sensing elements is the most appropriate approach for identifying changes that are of biological significance. We have chosen to test the biosensing affinity arrays invention described here using the lectins. We shall describe lectins and give several advantages this class of proteins has over the more commonly used immune-based diagnostics in the application of this invention.
[0010] Lectins as biological recognition elements. As mentioned previously, lectins bind carbohydrates and to compounds with similar structure. (Lectins as molecules and as tools. Lis, H. And Sharon, N. Ann. Rev. Biochem., 55, 35-67, 1986; Advances in Lectin Research . Vol 1, Franz, H. Ed., Springer-Verlag, Berlin, 187 pp., 1987). Lectins also have the capability to agglutinate cells, precipitating polysaccharides and glycoproteins and are of nonimmune origin. This is due to the fact that they are oligomeric in structure, usually containing one sugar binding site per subunit. In this respect, lectins have agglutinating abilities similar to those of antibodies. They also can be inhibited by low molecular weight compounds, which in the case of lectins are small carbohydrates, such as monosaccharide, oligosaccharides or macromolecules which contain them.
[0011] First, lectins provide a broad spectrum of well defined binding specificities with a high degree of cross reactivities as compared for example with antibodies and enzymes. Furthermore, they are stable and have a wide range of affinities and specificities. In addition, over one hundred lectins have been characterized. It now appears that lectins mediate a variety of cellular interactions during development and in the adult animal (Drickamer, K. And Taylor, M. E. Biology of Animal Lectins Annu. Rev. Cell Biol. 9:237-64, 1993). This is supported by data which shows that lectin expression patterns change throughout development and in response to a wide range of environmental changes [Varki, A. Biological roles of oligosaccharides: all of the theories are correct, Glycobiology, 3:97-130, 1993.]. The involvement of oligosaccharides in selectin-mediated cell-cell recognition by the immune system in response to inflammation [Lasky, L. A. Selectins: interpreters of cell-specific carbohydrate information during inflammation. Science 258:964-969, 1992 and sperm-cell recognition during fertilization [Miller, D. J., Macek, M. B., Shur, B. D. Complementarity between sperm surface b1,4-galactosyltransferase and egg coat ZP3 mediates sperm-egg binding. Nature 357:589-593, 1992) are but a few examples. It is also known that modifying the expression of glycosides and glycosyltransferases interferes with normal development. However, it has not been possible to define the individual contributions of individual monosaccharides residues and oligosaccharide chains to stage-specific and tissue-specific developmental processes.
[0012] An object of this invention is the ability of the assay strategy to discriminate complex samples which could be used to delineate complex basic developmental processes.
[0013] Second, the study of lectins is intimately linked to that of carbohydrates and is referred to as glycobiology ( Glycoproteins , Hughes, R. C. outline Studies in Biology, Chapman and Hall, London and New York, 95 pp, 1983). Glycosylation is used extensively in nature for a wide range of purposes some general, such as protease protection, some directed to particular classes of proteins, such as signaling mechanism for clearance of proteins from serum and some highly specific, such as cell adhesion. Carbohydrates also act as control mechanisms, as signals for cellular localization, for specific cell surface recognition of one cell type by another, for clearance of a particular glycoform from serum, assist in protein folding possibly by providing protection against proteolysis (Pareth, R. B. Effects of glycosylation on protein function. CUM Opin. Struct. Biol. 1:750-54, 1991).
[0014] Carbohydrates contain a potential informational content several orders of magnitude greater than any other biological oligomer. For example, if one calculates the number of possible structures for a hexamer of sugars and that of a hexamer of amino acids, the figure is >1.05×10 12 and 4.6×10 1 . The difference is more than seven orders of magnitude. Accordingly, sugars clearly provide the largest single source of diversity in the biological world (Laine, R. A. Invited Commentary in Glyco-Forum section Glycobiology 1994 8, 759-767).
[0015] Lectins have also been shown to be important in defense against a variety of pathogens. The mannose binding lectins in animals mediates antibody-independent binding of pathogens which contain a high concentration of mannose on their surface. These monosaccharides are not generally found in terminal positions on serum or cell surface glycoproteins in mammalian systems. The recognition event can initiate the complement cascade [Ikeda, K, Sannoh, T., Kawasaki, T. And Yamashima, I. (1987) J. Biol. Chem. 262, 7451-7454.]. Plant lectins have also been implicated in attachment of symbiotic nitrogen fixing bacteria to the roots of leguminous plants and int eh protection of plants against fungal pathogens (Bohlool, B. B. and Schmidt, E. L. (1974) Science 185:269-71).
[0016] Third, numerous pathogens use carbohydrate-lectin interactions in order to gain entry into their hosts. For example, bacteria and intestinal parasites, such as amoeba, mediate the sugar specific adherence of the organisms to epithelial cells and thus facilitate infection. (Liener, I. E., Sharon, N., Goldstein, I. J. eds (1986) The Lectins: Properties, functions and applications in biology and medicine. New York: Academic.). Viruses such as influenza virus (myxovirus) and Sendia virus (paramyxovirus) use a haemagglutonin protein that binds sialic acid containing receptors on the surface of target cells to initiate the virus-cell interaction (Paulsson, J. C. Interaction of animal viruses with cell surface receptors. in: The Receptors (Vol. 2) (ed. P.M. Conn), Academic Press, New York, pp. 131-219, 1985).
[0017] Another object of the invention is to study the pathogenesis of diseases that use carbohydrates or lectins in order to gain entry into cells.
[0018] Carbohydrate binding proteins such as selectins are believed to play a critical role in immune responses including inflammation (Springer, et al. 1991 Nature 349:196-197; Philips, et al., 1990 Science 250:1130-32. Specific carbohydrate ligands have been identified and have been used to control inflammation, immunosuppression, etc. through their interaction with selectin proteins and/or other lectins (Gaeta, et al., U.S. patent application Ser. No. 07/538,853, filed 15 Jun. 1990; Ippolito, et al., U.S. patent application Ser. No. 07/889,017, filed 26 May 1992). Other glycoproteins have also been shown to be useful in suppressing mammalian immune responses (Smith et al., U.S. patent application Ser. No. 07/956,043 filed 2 Oct. 1992).
[0019] Another object of the invention is to use the assay strategy in order to delineating the more subtle recognition functions of lectins, including but not limited to selectin and other lectins, in immune and inflammatory responses.
[0020] Fourth, the wide distribution of and ready availability of large numbers of sugars and sugar binding proteins combined with their ubiquity throughout nature, has led to their extensive use as reagents for studying carbohydrates in solution and on cell surfaces. They were originally used for blood typing (Lis and Sharon), for the identification and separation of cells (Sharon, N. 1983 Adv. Immunol. 34:213-98). Labelled lectins serve as specific reagents for the detection of glycoproteins separated on gels, either directly or after blotting (Rohringer, R., Holden, D. W. 1985 Anal. Biochem. 144:118-27.) Immobilized lectins are routinely used for isolating glycoproteins such as the insulin receptor (Hedo; J. A., Harrison, L. C., Roth, J. 1981 Biochemistry 20:3385-93) and the many others proteins. Lectins have been widely used to separate cells such as thymocytes and splenocytes (Reisner, Y, Sharon, N. 1984 Methods Enzymol. 108:168-79; Maekawa, M., Nishimune, Y. 1985 Biol. Reprod. 32:419-25.). Numerous bacteria have been typed using lectins (Doyle, R. J., Keller, K. F. 1984 Can. J. Microbiol. 3:4-9; DeLucca, A . J. II 1984 Can. J. Microbiol. 3:1100-4). Primates can be differentiated from non-primates by the presence of specific sugar residues [Spiro, R. G. and Bhoyroo, V. D. (1984) J. Biol. Chem. 259, 9858-9866; Galili, U., Shohet, S. B., Kobrin, E. Kobrin, E., Stults, C. L. M., and Macher, B. A. (1988) J. Biol. Chem. 263, 17755-17762. These applications are strictly dependent upon the ability of a particular lectin to specifically identify a carbohydrate attached either to a soluble biomolecule or to a cell or organelle.
[0021] Fifth, most cells have a coating of carbohydrate chains in the form of membrane glycoproteins and glycolipids (in eukaryotes) or of polysaccharides (in prokaryotes). In eukaryotes, the cell type and environmental factors such as glucose concentration, play a major role in determining the extent and type of glycosylation, which is both species and tissue specific (Parekh, R. B., Dwek, R. A., Thomas, J. R., Opdenakker, G., Rademacher, T. W. (1989) Biochemistry 28, 7644-7662; Goochee, C. F. and Monica, T. (1990) Bio/Technology 8, 421-427). In addition, each individual enzymatic reaction may or may not go to completion, giving rise to glycoforms or glycosylated variants of the protein (Rademacher, et al. Ann. Rev. Biocehm., 1988 57:789-838). These factors give rise to the enormous heterogeneity of carbohydrate structures, found in vivo that has hindered their analysis. However, in some instances the relative concentration of the different forms have been shown to vary in specific ways in certain health and disease states. For example This also explains why glycosylation patterns of natural glycoproteins may be influenced by physiological changes such as pregnancy and also diseases such as rheumatoid arthritis.
[0022] In addition, it is known that the interaction between individual monosaccharides and CRDs is too weak to account for the affinities that lectins have for glycoproteins. The oligomeric lectins (multivalent) clusters the carbohydrate recognition domains (CRDs) which increases both the specificity and the affinity for multibranched oligosaccharides. While these effects are not well understood, it is clear that the density of CRD has biological significance. Thus, is an additional parameter that can be used in the invention to further increase the informational content of the assay. This would indicate that lectins could be useful following changes in the overall state of complex biological samples. This wealth of diversity provides a nearly unlimited range of sensor elements from which to choose.
[0023] It is believed that the multivalency of lectins for carbohydrates is important for their biological activity. Thus, an object of the invention would be the application of density gradients of lectins on surfaces in continuos and discontinuous, as well as in homogeneous and heterogeneous formats for sample discrimination. This would provide a unique tool for gaining a basic understanding of the effect of binding site density on the recognition process. Methods are available to those skilled in the art for adapting reflectometry, ellipsometry or SPR for scanning and imaging modes. This also would provide an additional assay parameter, thus increasing the informational content of the lectin affinity arrays and thereby improving their ability to discriminate complex samples.
[0024] Diagnostic assays strategies. Immunoassay based diagnostics currently predominate the market, nevertheless, lectins provide some advantages over conventional immunoassays. Lectins are present in most life forms and more importantly they are found in life forms such as plants, microorganisms and viruses, which do not synthesize immunoglobulin. Clearly the biological function(s) of lectins precedes that of the immune system, many of which are unknown at present. Thus, these sensing elements will be more useful for identification and classification purposes. The extensive homologies observed between different classes of lectins demonstrate that these proteins have been conserved throughout evolution and provide strong evidence that they have important function(s) in biology. Another difference is that lectins are structurally diverse whereas antibodies are structurally similar. This structural diversity would result in a corresponding diversity of stabilities that would increase the flexibility of the assay formats (antibodies tends to denature under similar conditions due to their structural similarity). Thus, lectins combine the multivalency of antibodies with the structural diversity of enzymes. Other proteins which bind carbohydrates also exist such as those that participate in carbohydrate metabolism and sugar transport. In general, these proteins only bind one carbohydrate and serve quite different purposes than lectins.
[0025] The detection of specified antigens, haptens and the like substances in bodily fluids such as blood, serum, sputum, urine, and the like is of central importance in both research and clinical environments. The detection of such ligands can often be correlated to various disease states and consequently, is of great importance in diagnosis and for gaining a basic understanding concerning the genesis of disease, as well as for monitoring the efficacy of therapeutic treatments. The large and ever increasing ability to diagnose and treat diseases has lead to an explosive increase in demand for diagnostic testing. And while the cost per assay has been reduced, the number of tests that are performed has increased dramatically. This is in part due to the increasing number of tests that are available and in part due to the need medical practitioners have to be able to justify their actions in the event that legal action (malpractice suits) should be taken against them.
[0026] Accordingly, improved methods for detecting ligands in aqueous samples are constantly being sought. In particular, such preferred methods or assays are those that are faster, more flexibility, simpler to perform and manufacture, as well as having low manufacturing costs. In addition, there is an increasing need for strategies that will reduce the time necessary to develop diagnostic assays for such agents as HIV and Bovine Spongiform Encephalitis (B SE). Increasing health costs require the development of new, rapid, and more effective diagnostic strategies.
[0027] In general, immunoassays are based upon the immunological reaction between proteins such as antibodies, antibody fragments, or even artificially generated elements simulating antibody binding sites such as peptides, templated polymers and the like (hereafter referred to as antibody recognition) and the substance for which they are specific, the ligand. Immunological reactions are characterized by their high specificity and accordingly, numerous schemes have been developed in order to take advantage of this characteristic. The goal is to identify a particular state with absolute specificity using as few assays as possible.
[0028] In the traditional heterogeneous forward assay, an antibody is immobilized on a solid phase such as microparticles, microtiter wells, paddles, and the like. The sample is then contacted with the immobilized antibody and the ligand binds if present in the sample. The bound substance is detected and quantitated by an entity associated directly or indirectly therewith. Such detectable entity include fluorescent molecules, chemiluminescent molecules, enzyme, isotopes, microparticles and the like. Many variants have been developed such as competition, indirect competition, and the like. Various methods are available to those skilled in the art for quantitating the amount of substance bound using these assays.
[0029] In addition to immunoassays, other diagnostic assays are available based upon the same demand for absolute specificity using wide range of recognition elements such as proteins (lectins, receptors, and the like), nucleic acids, carbohydrates, lipids and/or synthetic/engineered biomimetic compounds and the like. A wide range of basic techniques have also been developed including but not limited to microscopy, chromatography and electrophoresis in order to specifically identify diseases.
[0030] It is an object of this invention to provide an assay strategy for sample discrimination which relies upon an array of sensing elements with low specificity in order to increase the informational content of the diagnostic assay. The assay strategy is capable of discriminating subtle changes and thus allows early identification of changes in the state of health that can be of crucial importance. In some instances, the sensing elements used in conventional assays will be applicable. However, in most instances the specificity of these reagents will be too high to allow their use. Accordingly, new screening procedures will be developed in order to isolated reagents with appropriate combination of affinities and specificities and is an object of this invention, as well.
[0031] The assay strategy can be extended to a wide range of applications that require complex sample discrimination including but not limited to identification of diseases, identification of changes caused by the disease itself in the host (including but not limited to human, animal, plants and microorganisms). Complex samples containing biological material and/or degradation products including but not limited to such as food stuffs like beverages, dry foods, and the like (including but not limited to quality control, for detection of unwanted microbial growth, freshness, physical damage), as well as the control of environmental samples for microbial flora (including but not limited to microbial content and composition), pollutants and their breakdown products in air, soil and water samples. This strategy and assays based on it could also be used for monitoring fermentation processes, including but not limited to yogurt, beer, wine and the like, broths, as well as in fermentation processes in which products are produced such as biological compounds produced by microbial processes, such as insulin from genetically engineered bacteria and the like, as well as condiments made for seasoning and the like, as well fermentation processes used in the production of animal food stuffs.
[0032] Current diagnostic testing approaches used to determine the general state of health such as hemoglobin, blood pressure and the like give only limited information. And while these tests provide useful information as to the general state of health, they do not provide adequate information to identify diseases nor are they sensitive enough to detect subtle changes required for early disease detection. There is a need, therefore, to develop new strategies for the identification of disease states which provide information as to which class of ailments the patient is suffering in order to reduce the number of specific tests which must be performed.
[0033] Another object of the invention is to provide a strategy and assays for improved techniques to monitor the general state of health to assist efforts in identifying ailments early on thereby allowing treatment to begin at an earlier stage than would have been possible otherwise. The early treatment of disease has been shown to reduce health care costs. This strategy would also be useful in preventative health care schemes. A similar situation exists in food stuff and environmental testing.
[0034] This diagnostic strategy based on the use of discrete recognition elements with broad recognition specificities combined with computer based artificial neural network data analysis can also be used with discrete synthetic biomimetic recognition elements with appropriate specificity (signal to noise). These could be made from modified biological material or from polymeric materials by conventional templating techniques and the like. This embodiment of the invention would be especially useful in applications requiring assay conditions that would destroy or dramatically reduce the binding affinity and/or specificity of conventional biological sensing elements including but not limited to organic solvents, high or low temperature, acidic or basic solutions and salts.
[0035] These detection techniques demand highly reproducible, high density immobilization methods for flat surfaces such as silicon wafers or flat glass. Other surfaces compatible with these detection techniques including but not limited to plastic, silicon, mica and glass surfaces in both metal coated or uncoated. Standard immobilization protocols resulted in poor overall reproducibility due to inadequate signal to noise ratios. A method was developed that allowed high density immobilization of biomolecules with high retention of biological activity while minimizing nonspecific binding assay. The increased sensitivity and reduced nonspecific binding achieved increased the signal to noise ratio that was essential for this assay strategy. We now believe that the nearly 100% surface coverage. This prevents interaction directly with the metal surface, and provides an essentially homogenous interaction matrix, and maximizes surface densities.
[0036] The strategy could be used to discriminate complex samples from other origins including but not limited to, body fluids such as blood, serum, saliva, sputum, urine and the like, thus allowing complex correlations with known reference standards (using pattern recognition programs). Environmental samples such as air, soil, water and the like, food stuffs and the like as well as artificial substances for which appropriate sensing elements can be found could be analysed using this strategy, i.e. appropriate signal to noise ratios can be obtained for the samples in question. No analytical approach can currently exists which can discriminate samples as rapidly or as cost effectively. An important object of the invention is the ability of the strategy to take advantage of as yet unknown recognition functions present in the recognition elements.
[0037] We have not made any attempt to identify the substances bound to the lectin arrays but various methods are available to those skilled in the art of identifying biomolecules to perform this type of analysis. While this is not the primary aim of the invention, it may prove useful for understanding the nature of changes that have occurred that may assist in the development of therapies and/or the development of therapeutic drugs. In addition, any recognition element which exhibits the characteristics required by this assay strategy, including but not limited to biomolecules such as proteins, lipids, carbohydrates and nucleic acids, modified biomolecules, such as genetically engineered, chemically modified, and the like, as well as synthetic molecules used in molecular recognition, such as cyclodextrans, templated and imprinted polymers and the like, may also be used in this regime.
[0038] Another object of the invention is the combined approach used to immobilize the biomolecules and included special surfaces (gold), hydrophobic thick-film patterning, self-assembling long chain thiols with terminal carboxylic acid groups and an empirically determined EDC/NHS immobilization protocol. While all of these have been used individually, no immobilization protocol exists which combines these various techniques into a single unified protocol.
[0039] Numerous patents have been disclosed which employ a wide range of biological sensing elements for diagnostic and therapeutic purposes, such as WO 95/29692, WO 95/15175, WO 95/28962, WO 95/07462, Canadian patent 2,133,772, U.S. Pat. No. 4,289,747, U.S. Pat. No. 4,389,392, U.S. Pat. No. 4,298,689 and WO 95/26634. All of these inventions use the unique specificity of some sensing element, be it an antibody or a lectin, to identify a single disease (or groups of highly related diseases). Great attempts are made to increase the specific reaction and reduce the nonspecific reactions, in strong contrast to the invention described here.
[0040] WO patent 92/19975 describes a method for labelling glycoproteins with a fluorescent molecule in a complex mixture using a carbohydrate specific labelling reagent. This mixture of labelled proteins is separated and the banding pattern analysed using pattern recognition techniques.
[0041] Our invention has several advantages over this invention. First, no separation steps are involved which reduces the time, labour, cost and complexity of the assay. Second, no recognition elements are used, limiting the flexibility of the assay. Third, since no recognition elements are used the analysis of known or unknown binding functions is not possible. And finally, the assay cannot be expanded which restricts the ability of the assay to take full advantage of pattern recognition programs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] FIG. 1 a . Schematic overview of the immobilization procedure using 8 sensing fields.
[0043] FIG. 1 b . Schematic overview of the immobilization procedure using 2×96 sensing.
[0044] FIG. 2 . Schematic of the fixed angle scanning ellipsometer.
[0045] FIG. 3 . Chart of the animal sera responses.
[0046] FIG. 4 . Chart of the human healthy vs sick responses.
DETAILED DESCRIPTION OF THE INVENTION
Example 1
[0047] Interfacing these biological sensing elements with the surface mass based optical imaging technology was very difficult. Standard immobilization protocols resulted in poor overall reproducibility and lead us to develop a highly specialized protocol which combines surface patterning and immobilization technologies ( FIG. 1 ). The integrated assay format which combines thick film surface patterning, self-assembling monolayers, efficient coupling chemistries and the biotin-streptavidin. The procedure employs a proprietary teflon based thick-film printing ink (Cel-line, USA) to pattern gold coated silicon wafers or glass combined with self-assembling carboxyl-terminated long chain thiol alkanes onto the exposed gold surfaces. Polished silicon wafers (Wacker Chemie, Germany) or glass were coated with gold by evaporation as described (Mårtensson, J., Arwin, H. Interpretation of spectroscopic ellipsometric data on protein layers on gold including substrate-layer interactions. (1995) Langmuir 11:963-968.). These surfaces were then patterned with a proprietary hydrophobic coating using thick-film technology (Cell-line, USA). The hydrophobic thick-film patterning greatly simplified localization of the various reagents which lead to a dramatic improvement in the overall reproducibility of the assay protocol. The wafers were sonicated in EtOH prior to being treated with HS—(CH 2 ) 16 —COOH (1 mM in EtOH). The surfaces were rinsed with EtOH, then sonicated in EtOH and finally rinsed again in EtOH. The surface was then activated using NHS (0.2M) and EDC (0.8M) in distilled water for 60 min at room temperature. The surface was briefly rinsed with distilled water and blown dry with nitrogen gas. Amino-biotin (Molecular Probes, USA) was added (1 mM in 100 mM carbonate buffer, pH 8.5) and incubated at room temperature for 60 min. After briefly rinsing the surface with distilled water, 50 ug/ml streptavidin (Molecular Probes) in HBST (150 mM NaCl, 0.1% tween 20 and 20 mM Hepes, pH 7.4) and incubated 30 minutes at RT. The surface was washed and 50 ug/ml (diluted in HBST) of the biotinylated biomolecule of choice was applied to the appropriate and incubated for 60 min at RT. An overview is shown in FIG. 1 .
[0048] Another object of the invention is the combined approach used to immobilize the biomolecules and included special surfaces (gold), hydrophobic thick-film patterning, self-assembling long chain thiols with terminal carboxylic acid groups and an empirically determined EDC/NHS immobilization protocol. While all of these have been used individually, no immobilization protocol exists which combines these various techniques into a single unified protocol.
[0049] The immobilization procedure was empirically optimized by quantitating the amount of radiolabelled streptavidin or human serum albumin. SA and HSA were radiolabelled using the S 35 protein labeling reagent (SLR) according the manufacturers recommendations (Amersham, UK). For the double labeling HSA was first lightly labeled with biotin, dialyzed and subsequently with SLR. Labeled protein (usually 10 7 cpm/ug protein) was diluted with unlabeled protein and added to the wells. The amount of material immobilized was quantitated using a Fuji Phosphorimager. The protocol was highly reproducible (n=10, S.D.=5%). Surface density calculations and other evidence indicate that SA is present as a tight monolayer on the surface. AFM as well as ellipsometric experiments indicate the surface is extremely uniform. In addition, we have calculated the SA packing density to be 60,000 SA/mm 2 using the radiolabelling data. This is 20% higher than the theoretical packing of 50,000 SA/mm 2 and can be accounted for by the roughness of the gold surfaces used in these experiments. A gold corn size of 20 nm (determined from atomic force microscopy of the surfaces) corresponds to an accessible area of 70,000 SA/mm 2 . The a highly reproducible immobilization is absolutely required in order to achieve adequate assay reproducibility and for studying the effects of CRD density gradients.
[0050] This protocol was used to pattern an array of eight biotinylated lectins: canavalia ensiformis, bandeiraea simplicifolia BS-I, arachis hypogaea, phytolacca americana, phaseolus vulgaris pha-e, artocarpus integrifolia, triticum vulgaris, pisum sativum . Pooled sera from Sheep, Goat, Swine and Human (DAKO, Danmark) were diluted 1:4 in RBST and 5 μl was added to each well. After an overnight incubation at 4° C., the samples were washed with buffer and then briefly with distilled water (to remove excess salts which disturbed the ellipsometric measurements). The samples were then placed on the XY stage of a scanning fixed angle ellipsometer which was build at the Laboratory of Applied Physics (Arwin, H., Lundström, I. Surface oriented optical methods for biomedical analysis. (1988) Method in Enzymology 137:366-381; Jin, G., Tengvall, P., Lundström, I., Arwin, H. (1995) Applications of imaging ellipsometry for antigen-antibody binding studies. (1996) Analytical Biochemistry, in press). The apparatus consisted of a 670 nm diode laser (Melles Griot, Sweden) equipped with an aperture, polarisers and a multi-order quarter-retardation plate, arranged in such a way that plane polarized light fell on the sample surface at an appropriate angle. The reflected light was measured using a photodiode. A computer was used to control the position of the sample and to store data obtained from the photodiode. The size of the light spot from the laser was in the order of 1 mm 2 , thus defining the maximum resolution. The distribution and amount of proteins adsorbed on the surface could then be evaluated or visualized by scanning the sample. The equipment allowed for scan areas up to 20×20 mm with a resolution of up to 200×200 pixels. The experimental arrangement is schematically shown in FIG. 2 . The raw values obtained from the experiments were treated with the image analysis program Transform (Spyglass, U.S.A.) or NIH Image to quantitate the data.
[0051] The data obtained from one such experiment is shown in FIG. 3 . This data was input into a three layer artificial neural network consisting of 8 nodes corresponding to the 8 lectins. In the first run, the untreated raw data was input and training quickly lead to convergence, that is to say the net was able to discriminate between the sample.
Example 2
[0052] In these studies, sick vs healthy human serum samples were analysed using the same array of eight biotinylated lectins: canavalia ensiformis, bandeiraea simplicifolia BS-I, arachis hypogaea, phytolacca americana, phaseolus vulgaris pha-e, artocarpus integrifolia, triticum vulgaris, pisum sativum. In this case, unpatterned gold (50 nm thick gold evaporated by sputtering) coated glass (0.3 mm thick glass) surfaces were prepared essentially as described above up to and including the coupling of amino-biotin. The surfaces were then inserted into the BIAcore from Pharmacia Biosensor. The running conditions were 2 μl/min, at 25° C. and the running buffer was HBST. The binding of the SA and biotinylated lectins was performed by sequentially injecting 4 μl of a 50 μg/ml solution of each.
[0053] The human sera were obtained from the Infectious Diseases Department at Lunds University Hospital. The reference sera were taken from healthy volunteers (20 individuals). The sick sera samples (8 individuals) all been identified as having clinical bacterial infections. The sera were diluted 4:1 with HBST and 30 μl was injected. After, completion of the injection, a value was taken in reference units (RUs). The surface was regenerated down to the biotin by injecting regeneration solution. SA and biotinylated lectin were then injected sequentially to begin the next binding study. This process was repeated until all of the serum samples had been analysed by all eight lectins. The results from one such experiment are shown in FIG. 4 . Seven out of the eight sick individuals can be clearly identified as sick when compared with the healthy reference serum samples.
[0054] We originally intended to use antibodies for these studies. However, we were unable to find monoclonal antibodies with an appropriate combination of affinity and specificity. This could be due to the screening procedure used to select these antibodies or possibly due to suppression of broadly cross-reacting antibodies. | Described is a method for discriminating complex biological samples using an array of discrete biological sensing elements immobilized onto a solid support in which constituents bound to the sensor array is directly determined by measuring the mass increase on the surface; data analysis of said method is performed using neutral network or statical based pattern recognition techniques. In a preferred embodiment the liquid sample is tested for the presence of soluble constituent(s) by contacting said sample with said sensor array under specific conditions, removing unbound sample constituent(s), determining the mass increase on the surface and comprising said mass increase data with a reference standard using pattern recognition software. | 8 |
BACKGROUND OF THE INVENTION
Incubators for hatching eggs are known in which there is provided a heating means such as an electric element, for example that in a light bulb, and in which the air heated by the heating means passes upwardly around the eggs so as to warm eggs. This, however, is somewhat unnatural because in a nest the bird sits on the eggs and in nature heat is transmitted downwardly through the bird's plumage by conduction to the eggs.
It is also known to rotate eggs periodically, as it is considered desirable to prevent the developing embryo from sticking to the membrane within the egg. One known method for turning the eggs is to put a cross on one side of the egg and a circle on the other side of the egg and for the eggs to be turned by hand periodically. This is particularly laborious. In a known mechanical device for turning eggs, the eggs are put into a rack with their major axes vertical. The eggs are securely clamped in the rack and from time to time, for instance every quarter of an hour or every four hours, the rack is rotated through 90° about a horizontal axis.
Whilst such a device gives tolerable results with the eggs of a reasonably domesticated birds, such as chickens and ducks, this device when used with the eggs of less domesticated birds, such as pheasants and geese, gives results which leave considerable room for improvement.
There is thus a need for an incubator which, by reproducing the effects found in nature, will give satisfactory hatching results.
SUMMARY OF THE INVENTION
The present invention provides an incubator which comprises:
a housing for accommodating eggs to be hatched;
support means within the housing, for supporting eggs;
a flexible screen for placing over eggs on the support means;
heating means for heating air; and
guide means for guiding air, heated by the heating means, above the flexible screen whereby, in use, the screen is heated and heat is conducted downwards through the screen so as to heat upper regions of eggs.
Conveniently the screen is formed of a soft fabric, for example the fabric of a conventional blanket.
The incubator according to the present invention may also include a fan for forcing heated air across the top of the screen. The air may be heated by, for instance, a light bulb. The incubator may also include means for humidifying the air being passed across the top of the screen, so that the air above the eggs has a temperature and humidity corresponding to those of air above eggs in a nest when a bird is sitting. In such a case, the screen may be slightly porous, to permit the passage of air through the screen.
Conveniently the housing comprises a container portion and a cover portion, the screen being dependent from the cover portion such that, with eggs on the support means and with the cover portion on the container portion, the screen rests on the eggs.
Conveniently the support means is a tray, there being dividers above the tray to divide eggs on the tray into rows, there being provision for relative movement between the tray and the dividers, and there being motive means for intermittently causing said relative movement, thereby to cause intermittent rotation of the eggs.
A preferred embodiment is that wherein the tray is reciprocable with respect to the housing and moves freely on roller means, the tray is provided with two downwardly directed lugs, and the said motive means includes a motor with an arm inclined to the shaft of the motor, such that actuation of the motor causes the arm, in one complete circular movement of the arm, to urge one lug and hence the tray in one direction and then to urge the other lug and hence the tray in the opposite directtion.
The incubator may include two parallel rows of notches, whereby dividers can be positioned so that the distance between two adjacent dividers is slightly greater than the diameter of the eggs to be hatched.
The present invention also provides an incubator which comprises:
a housing for accommodating eggs to be hatched;
a tray within the housing, for supporting the eggs;
heating means for heating air;
dividers, for dividing eggs on the tray into rows; and
motive means for intermittently causing relative movement between the tray and the dividers.
Whilst with devices of the known type described above for hatching pheasant eggs a success rate of up to 50% can be achieved, the applicant has found that when hatching pheasant eggs with an incubator in accordance with the present invention which incorporates the screen heated from above and means for rotating the eggs by virtue of the relative movement between the tray and the dividers, a success rate as high as 90% can often be achieved.
Another significant difference between the aforesaid known devices in which the air surrounding the eggs is heated, and the incubator according to the present invention, is that in the known devices the heating of the air surrounding the eggs tends to increase evaporation from the surface of the eggs, which means that high levels of humidity are often required to reduce this effect. In contrast, in the incubator of the present invention the heat is conducted downwardly through the screen to the top of the eggs. Moreover, in the incubator according to the present invention, the eggs lie with their major axes horizontal, which is a more natural position, as found in a nest in nature. In practice, the temperature of the underside of the screen is preferably similar to the surface temperature of a sitting bird, so as to reproduce as effectively as possible the natural environment.
As indicated above, the screen may be porous, to permit some equilisation of the vapour pressure, resulting in the emission of moisture from the underside of the screen, equivalent to the moisture emitted from a bird. However, generally, the porosity of the screen is not sufficient to permit free interchange of air above and below the screen.
The tray on which the eggs are supported may be provided with apertures, to provide some ventilation.
Desirably, the dividers are spaced apart a distance which is slightly greater than the diameter of the eggs to be hatched, so that there is only a slight degree of free play in the system; this means that when there is relative movement between the tray supporting the eggs and the dividers dividing the eggs into rows, there is adequate rotation of the eggs. The dividers may be made from metal or a stiff plastics material and may resemble a rod or strip or may have some other appropriate cross-section.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:
FIG. 1 is a vertical section through one embodiment of an incubator according to the present invention, taken parallel to the major dimension of the incubator;
FIG. 2 is a transverse cross-section through the incubator of FIG. 1, taken along the line II--II shown in FIG. 1;
FIG. 3 is a transverse cross-section through the incubator of FIG. 1, taken along the line III--III shown in FIG. 1;
FIG. 4 is a side view, on an enlarged scale, of part of the incubator shown in FIG. 1, with the eggs in position; and
FIG. 5 is an isometric view, on an enlarged scale, showing part of the mechanism for causing reciprocating movement of the tray.
DETAILED DESCRIPTION
Referring in the first place mainly to FIGS. 1, 2 and 3 of the drawings, the incubator comprises a container portion generally indicated by the reference numeral 1 and a cover portion generally indicated by the reference numeral 2.
As regards the container position 1, a platform 3 extends between two side walls 4 and 5 over a major portion of the length of those walls. Extending between the opposite end regions of the side walls 4 and 5 are two end walls 6 and 7. The platform 3 extends from the end wall 7 to a transverse intermediate wall 8 which is intermediate the end walls 6 and 7 but nearer the end wall 6. Extending between the end wall 6 and the intermediate 8 is a dividing wall 9 (shown most clearly in FIG. 3). Bounded by the side wall 5, end wall 6, dividing wall 9 and intermediate wall 8 is a heating compartment 10; and bounded by the side wall 4, the intermediate wall 8, the dividing wall 9 and the end wall 6 is a humidifying compartment 11. Supported in the heating compartment 10 is a sub-frame 12 which supports an electric heater 13, an electric motor 14 for driving a fan 15, and a control unit 16 for controlling the electric heater 13.
Provided in the inward facing surface of the side walls 4 and 5 are two parallel rows of notches 17, one row being in the side wall 4 and the other in the side wall 5.
Provided in the platform 3 are four slots 18 parallel to the major dimension of the incubator, there being two slots 18 on one side region of the platform 3 and two slots 18 on the opposing side region of the platform 3. Rotatably mounted in the four slots 18 are four wheels 19, and mounted on the wheels 19 is a tray 20, there being two angle pieces 21 attached to the underside of the tray 20 in opposing edge regions such that the upper regions of the wheels 19 bear against the angle pieces 21.
In some of the notches 17 are dividers 22 (shown in FIG. 4) which takes the form of rods extending from one row of notches 17 to the other row of notches 17 and which serve to divide eggs on the tray 20 into rows.
Below, and secured to, the tray 20 is a plate 23 provided with two downwardly directed lugs 24 and 25. Mounted in a central region of the platform 3 is an electric motor 26 having a suitably geared-down drive shaft 27 to which is secured a forked arm 28, the free end regions of the forked arm 28 carrying a freely rotatable wheel 29. The arrangement is such that in use rotation of the shaft 27 of the motor 26 causes rotation of the arm 28 so that the wheel first abuts against the lug 25 thus causing the plate 23 and hence the tray 20 to move in one direction, after which the wheel 29 moves clear of lug 25; the shaft 27 and arm 28 continue to rotate in the same direction and in due course the wheel 29 abuts the lug 24 and for some time causes the lug 24 and hence the plate 23 and tray 20 to move in the opposite direction to that in which the lug 25 was caused to move. This continues until the wheel 29 becomes free of the lug 24, after which the arm 28 continues to rotate until such time as the wheel 29 re-engages the lug 25.
Eggs 30 are shown resting on the tray 20 in FIG. 4 and it will be appreciated that, because of the limited space between the two dividers 22 of an adjacent pair, a reasonable movement of the tray 20 relative to the dividers 22 causes rotation of the eggs 30 about their major axes.
Provided in the platform 3 are apertures 31 for ventilation purposes, and for similar purposes the tray 20 is perforated.
Turning now to the cover portion 2, this includes a flat portion 35 with two dependent side walls 36 and 37, and two dependent end walls 38 and 39. Extending between the side walls 36 and 37 is an intermediate transverse wall 40 provided with two apertures 41 and 42, and extending between the intermediate transverse wall 40 and the end wall 38 is an intermediate longitudinally extending wall 43. Also dependent from the flat portion 35 is a dependent wall 44 which is parallel to the side walls 36 and 37 and extends from the intermediate transverse wall 40 in the direction of the end wall 39 but stops short of the end wall 39.
Secured to the lower end regions of the end wall 39, transverse wall 40 and part of the side walls 36 and 37 is a flexible screen in the form of a sheet 45 of blanket material. Also indicated in FIG. 3 is the level 46 of water in the humidifying compartment 11.
The position of the walls of the cover portion 2 is such that the side walls 36 and 37 cooperate with the side walls 4 and 5, and the end walls 38 and 39 cooperate with the end walls 6 and 7, to form a resonable seal. Additionally, the walls 40 and 8 cooperates to form a seal between, on the one hand, the compartment where the eggs are to be supported and, on the other hand, the heating and humidifying compartments 10 and 11, except for the apertures 41 and 42. The dependent wall 43 is offset with respect to the dividing wall 9 so that, in use, air may pass above the humidifying compartment 11, then over the wall 9, and then down into the heating compartment 10.
In use of the incubator, eggs 30 are carefully laid on the tray 20 with their major axes horizontal and perpendicular to the major dimension of the incubator. The dividers 22 are placed in the appropriate notches 17 so as to allow merely slight movement of the eggs 30. Water is introduced into the humidifying compartment 11 up to the mark 46, the control 16 is actuated to operate by varying the speed of the motor 26. The cover portion 2 is placed over the container portion 1 so that the underside of the sheet 45 contacts the upper regions of the eggs 30. Air is heated in the heating compartment 10 by the lamp 13 and is forced by the fan 15 into a zone above the sub-frame 12; from here it passes through the aperture 41 and then moves across the sheet 45 away from the aperture 41. It then returns towards the aperture 42, on the opposite side of the wall 44, and, after passing through the aperture 42, passes across the body of water in the humidifying compartment 11. The resulting humidified air then passes over the top of the dividing wall 9 and back into a lower region of the heating compartment 10.
The fan 15 is operated at such a speed as to ensure that the warmed air passed across the top of the sheet 45 moves sufficiently rapidly to ensure minimal temperature differences between different regions of the sheet 45. Depending on the size of the eggs 30, the length of the arm 28 and the spacing between the lugs 24 and 25, the eggs 30 can be rotated through up to 180° and then back through approximately the same angle, in every complete cycle. The cycle can take, for example, one hour, although this can be varied according to the farmer's preference, by varying the speed of the motor 26.
The particular mechanism for effecting reciprocation described above, namely the relationship between the arm 28 and wheel 29, on the one hand, and the plate 23 with its lugs 24 and 25, on the other hand, enables the tray 20 to be lifted out of the container portion 1 for cleaning purposes, after the eggs have hatched. Obviously, once the eggs begin to hatch, the reciprocating movement of the tray 20 is stopped, to avoid any injury to the emerging bird.
Depending on ambient conditions, the incubator can be operated without the eggs being present, until the desired temperature and humidity are attained, after which the cover portion 2 can temporarily be removed while the eggs are loaded into the container portion 1. | An incubator is disclosed in which there is a support for supporting eggs, with a flexible screen intended to be positioned over the eggs when supported by the support. There is also provision for hot air to be passed over the screen so that heat is conducted downwardly through the screen to upper portions of the eggs. In addition, or as an alternative, there can be transverse dividers for dividing the eggs into rows on the support, with provision for relative movement on an intermittent basis between the support and the dividers so as to cause rotation of the eggs. | 0 |
This application claims the benefit of French Application 03.50644, filed Oct. 3, 2003, the entirety of which is incorporated herein by reference.
The present invention relates to a civil engineering structure ensuring protection against impacts of moveable masses and of projectiles, more particularly of stones. It also relates to an individual construction element intended for the production of protective structures in the field of civil engineering and public works. Another aspect of the invention is concerned with a method for reinforcing a structure ensuring protection against impacts.
PRIOR ART
In mountainous regions and in all steep places, the roads, railway lines and residential areas are often threatened with falls of stones, landslides and slumps coming from cliffs or overhanging slopes. Thus, in spite of regular drainages of cliffs, infrastructures are additionally provided, which are interposed between the zone to be protected and the sources of projectiles.
In order to ensure this protection, various types of equipment are used, in particular reinforced-concrete walls or else nets and grids capable of retaining stones. There are also structures known as “barricades” produced, for example, from sheet-pile cells or else from embankments. These barricades are arranged between the cliff and the zone to be protected, thus defining a trench in which the stones which have fallen from the cliff accumulate. Where high impacts are concerned, the exposed face of the barricades may be deformed and damaged. It was found that these barricades are repaired only very rarely even if they have undergone serious damage.
It is also known, from the document FR-2,835,266, to use worn tyres which are added as the facing of a structure produced from concrete. All these solutions have disadvantages.
The existing concrete structures also have the disadvantage of cracking or of being downright destroyed in the event of impacts by moveable masses having high kinetic energy. Moreover, these infrastructures have much larger dimensions in relation to the actual protection requirements. To be precise, it is extremely difficult to conduct a diagnosis on a damaged barricade. This generally leads to an over dimensioning of the barricade in order to ensure that it fulfills its protective function after one or more high impacts.
As regards the barricade comprising tyres on the exposed face, a repair of such a structure involves the complete renovation of the facing and of the rear reinforced barricade in the impacted zone. This renovation is a cumbersome operation which also has to be carried out in especially hazardous locations subject to stone falls. Furthermore, the addition of elements which seem like refuse gives the structures an aesthetic appearance which is not necessarily acceptable.
Presentation of the Invention
A main problem which the invention proposes to solve is to provide a civil engineering structure which can easily be repaired. A second problem is to design a structure having mechanical properties such that it doesn't require overdimensioning in order to ensure its protective functions. A third problem is to improve the aesthetic and ecological appearance of the structures, whilst at the same time preserving their functional appearance. A fourth problem is to develop an individual construction element capable of limiting the damage undergone by the entire civil engineering structure with which it is associated. A fifth problem is to produce an element which can be prefabricated outside the hazardous zones, that is to say those subject to stone falls. A sixth problem is to implement a method making it possible to reinforce a pre-existing protective structure.
The invention therefore relates to a civil engineering structure intended for ensuring protection against impacts of moveable masses and having a face exposed to the impacts of moveable masses.
According to a first aspect of the present invention, the structure is characterized in that it comprises, in the region of the face exposed to the impacts of moveable masses, a set of individual construction elements secured to one another and filled completely or partially with at least one material having a capacity for being deformed elastoplastically, the individual construction elements liable to be damaged by impacts of moveable masses being capable of being replaced individually by similar individual construction elements.
In other words, by directly producing a protective structure comprising individual elements on the exposed facing, the main contractor can subsequently extract the individual elements damaged by stone impacts from the facing, and it can easily replace them by undamaged individual elements without intervening in the body of the structure. Moreover, due to the presence of these individual elements opposite a cliff, the structure as a whole will benefit from the energy absorption and protection properties. By the elastoplastic deformation of a material is meant a deformation of the material associated with its capacity for recovering its initial form, up to a threshold beyond which the deformation will be permanent.
These individual construction elements may or may not be associated with various types of structures forming the body of the overall structure. Thus, according to a first embodiment, the structure may comprise sheet-pile cells filled with pebbles or with fine materials isolated by means of a geotextile, and a set of individual construction elements arranged on that face of the structure which is exposed to the impacts of moveable masses.
According to a second embodiment, the structure may comprise an embankment reinforced with geotextile sheets or geosynthetic sheets or double-twist gridwork sheets or welded lattices or steel reinforcing bars, and a set of individual construction elements which are arranged on that face of the structure which is exposed to the impacts of moveable masses and which are or are not connected to the reinforcements.
The material having a capacity for being deformed may be selected, alone or in a mixture, from the group which may comprise pieces of shredded tyres, pellets cut from tyres, pieces of polystyrene, earthy materials, sands, gravels, pebbles, crushed recycled concretes, etc. The individual construction elements may have a, first volume of a first material having a capacity for being deformed elastoplastically and a second volume of a second, loose material.
The second, loose material is intended, for example, for aesthetically cladding the outer face and also absorbing part of the energy. The separation between the two volumes may be oriented in a plane substantially perpendicular to the mean direction of arrival of the moveable masses, in order to optimize the absorption of energy during the impacts. By loose materials are meant materials which experience deformation and which assume a given configuration when they are broken into fractions or when they are rearranged.
According to a second aspect of the present invention, each individual construction element, which forms a content delimited by an outer casing, may have a first volume of a first material having a capacity for being deformed elastoplastically and a second volume of a second, loose material, the separation between the two volumes being oriented in a plane substantially perpendicular to the mean direction of arrival of the moveable masses.
In other words, the individual construction and protection element is in two parts or two volumes, each having distinct mechanical properties. The first volume has properties of elastoplasticity with respect to impacts and the second volume has properties of absorption of part of the energy of the impacts. The moveable masses arrive at the structure in a preferential arrival and impact direction. The mean statistical arrival direction of these moveable masses is taken into account, in the knowledge that random rebounds and trajectories of moveable masses may occur. In many instances, the parting plane between the two volumes is substantially vertical.
The first material having the capacity for being deformed may be selected, alone or in a mixture, from the group comprising pieces of shredded tyres, pellets cut from tyres, pieces of polystyrene, earthy materials, sands, gravels, pebbles, crushed recycled concretes, etc. The second, loose material may be selected, alone or in a mixture, from the group which may comprise topsoil, sands, gravels, pebbles, rock blocks, crushed concrete, etc.
The outer casing may consist of a cage of a metal sheet-pile cell, and, if appropriate, the cage may be covered internally with a geotextile material. The separation between the volume of the material having the capacity for being deformed and the volume of loose material may be implemented by means of a wall made from a geotextile material or from gridwork or from a metal lattice, etc.
The individual construction element may likewise comprise a multiplicity of volumes, in succession a volume of loose material and a volume of first material having a capacity for being deformed elastoplastically. The separation between the volumes may be oriented respectively in a plane substantially perpendicular to the mean arrival direction of the moveable masses.
According to another aspect of the invention, a civil engineering structure, intended for ensuring protection against impacts of moveable masses and having a face exposed to the impacts of moveable masses, is characterized in that it comprises at least one element, as described above.
According to a third aspect of the present invention, a method for reinforcing a civil engineering structure, intended for ensuring protection against impacts of moveable masses, is characterized in that it comprises the steps involving:
positioning, in the region of the face exposed to the impacts of moveable masses, a set of individual construction elements which form a content delimited by an outer casing and which are filled completely or partially with at least one material having a capacity for being deformed elastoplastically; and securing the said individual construction elements to one another, so as to make it possible to replace individually the individual construction elements damaged by impacts of moveable masses with similar individual construction elements.
By virtue of the invention, any impact against the face will touch only one or more individual construction elements, without affecting the structural intactness of the structure.
BRIEF DESCRIPTION OF THE FIGURES
The invention will be understood clearly and its various advantages and different characteristics will become more apparent from the following description of the non-limiting exemplary embodiment, with reference to the accompanying diagrammatic drawings in which:
FIGS. 1 to 4 illustrate perspective views of four different embodiments of an individual element;
FIG. 5 illustrates a perspective view of a protective structure produced from individual elements; and
FIGS. 6 to 14 illustrate cross-sectional views of nine different embodiments of protective structures.
DETAILED DESCRIPTION OF THE INVENTION
As illustrated in FIG. 1 , an individual construction element ( 1 ) may take the form of a substantially parallelepipedal sheet-pile cell. The sheet-pile cell comprises an outer metal cage ( 2 ) produced, for example, from double-twist gridwork or from welded lattice work. The cage ( 2 ) may be closed by means of a lid ( 3 ). The sheet-pile cells are used for producing protective structures or for reinforcing existing structures.
According to one aspect of the invention, and in a first embodiment (see FIG. 1 ), the cage ( 2 ) has two distinct volumes ( 4 and 6 ). A first volume ( 4 ) is located at the front of the cage ( 2 ) with respect to the closing hinge of the lid ( 3 ). A second volume ( 6 ) is located at the rear of the cage ( 2 ) with respect to the closing hinge of the lid ( 3 ).
The first volume at the front ( 4 ) contains loose materials, by way of example pebbles, sands, gravels or topsoil. The second volume located at the rear ( 6 ) contains materials having elastoplastic properties, such as, for example, pellets or granules based on shredded tyres. The first volume at the front ( 4 ) is oriented, on the protective structure, on the same side as the face exposed to impacts.
Tyre granules obtained by means of the method described in the document FR-2,804,061 may be used. As an example, the pellets used may have dimensions of the order of a centimetre. The shredded tyres are held with the aid of a casing ( 7 ) produced, for example, from a geotextile material. A temporary geomat may also form the separation between the loose materials and the elastoplastic materials.
It will be noted that, depending on the desired function, the arrangement of the two volumes ( 4 and 6 ) may be reversed, as compared with the first embodiment of FIG. 1 . The first volume containing loose materials ( 4 ) may be arranged at the rear and the second volume containing materials having elastoplastic properties ( 6 ) may be arranged at the front on the same side as that face of the protective structure which is exposed to impacts.
In a second embodiment (see FIG. 2 ), the cage ( 2 ) likewise has the same two distinct volumes ( 4 and 6 ). However, the front face ( 5 ) exposed to impacts has an inclination, for example substantially equal to 45° with respect to the horizontal. Such an inclined front face ( 5 ) will allow a much easier establishment of plants, thus giving the cage ( 2 ) and the entire structure obtained by means of this type of cage ( 2 ) a much more attractive aesthetic and ecological appearance.
In a third embodiment (see FIG. 3 ), the cage ( 2 ) has a single volume ( 8 ). This single volume ( 8 ) contains materials having elastoplastic properties, such as, for example, shredded tyres, which are retained by means of a casing ( 7 ) produced, for example, from a geotextile material.
In a fourth embodiment (see FIG. 4 ), the cage ( 2 ) has three distinct volumes ( 9 , 11 and 12 ). A first volume ( 9 ) is located at the front of the cage ( 2 ), in this case with respect to the closing hinge of the lid ( 3 ). A second volume ( 11 ) is located at the rear of the cage ( 2 ), in this case with respect to the closing hinge of the lid ( 3 ). A third volume ( 12 ) is interposed in a central position between the first volume at the front ( 9 ) and the second volume at the rear ( 11 ). The first volume at the front ( 9 ) and the second volume at the real ( 11 ) contain loose materials, by way of example pebbles, sand, gravels or topsoil. The third, central volume ( 12 ) contains materials having elastoplastic properties, such as, for example, shredded tyres, which are retained by means of a casing ( 7 ) produced, for example, from a geotextile material.
FIG. 5 illustrates a protective structure ( 13 ) which is formed from a first stack of metal sheet-pile cells ( 14 ) secured to one another. These sheet-pile cells ( 14 ) are filled with materials of the stone or rock type. The structure ( 13 ) is oriented so as to have a vertical or inclined face which is more particularly exposed to falls of stones or other landslides. This structure ( 13 ) protects a road ( 17 ) and/or residences located at the bottom of the other flank of the structure ( 13 ), on the opposite side to the exposed face.
According to one aspect of the invention, the structure ( 13 ) comprises a facing ( 16 ) produced from removeable characteristic individual construction elements. In this example, sleet-pile cells having an inclined front face ( 1 ) and conforming to the second embodiment of FIG. 2 are used. These sheet-pile cells ( 1 ) are arranged with respect to one another and with respect to the conventional sheet-pile cells of the stack ( 14 ), in such a way as to have their first volume with loose material ( 4 ) on the exposed front face and to have their second volume with elastoplastic material ( 6 ) at the rear and against the sheet-pile cells of the stack ( 14 ).
According to another aspect of the invention, the sheet-pile cells of the facing ( 1 ) are easily removable and can be replaced if they are damaged. Thus, the method for repairing a civil engineering structure ( 13 ) may comprise the steps involving:
determining the individual construction element or individual construction elements, filled with a material having a capacity for being deformed elastoplastically, which are damaged by impacts of moveable masses and which are to be repaired or replaced ( 100 ); emptying this or these individual construction elements ( 100 ).
As regards the individual construction elements to be repaired, that is to say those which have undergone a local impact on the front face over a small area,
extracting that front face of the grid work which is damaged, by cutting it out; replacing this front face with an intact front face by binding or stapling, care having been taken, where appropriate, to complete the filling materials.
With regard to the individual construction elements to be replaced, that is to say those having undergone a very high impact which, for example, has damaged the entire front face,
extracting (arrow E in FIG. 5 ) from the civil engineering structure ( 13 ) these damaged individual construction elements ( 100 ) without contact with the other undamaged individual construction elements ( 1 ); adding (arrow A in FIG. 5 ) intact individual construction elements ( 1 ) in place of the damaged individual construction elements ( 100 ).
Various methods of protective assembly may be carried out on structures. Thus, in a first embodiment ( FIG. 6 ), a structure ( 18 ) with a stack of sheet-pile cells ( 14 ) comprises a protective facing ( 19 ) which is produced by means of sheet-pile cells according to the first embodiment of FIG. 1 . The structure ( 18 ) has a substantially vertical face exposed to the falls of stones ( 21 ). This structure ( 18 ) may likewise be produced by means of a stack of conventional sheet-pile cells filled with materials normally selected for a structure according to the prior art and of sheet-pile cells filled solely with elastoplastic materials according to the third embodiment of FIG. 3 .
In a second embodiment (see FIGS. 5 and 7 ), the structure ( 22 ) includes a solid structure formed from a stack of sheet-pile cells ( 14 ). It comprises, furthermore, a protective facing ( 19 ) which is produced by means of sheet-pile cells according to the second embodiment of FIG. 2 . The structure ( 22 ) has an inclined face ( 16 ) which is exposed to the falls of stones ( 21 ) and which may be established with plants.
In a third embodiment (see FIG. 8 ), the structure ( 23 ) includes a stack of sheet-pile cells ( 14 ) and comprises a central protective core ( 24 ) which is produced by means of sheet-pile cells according to the third embodiment of FIG. 3 . The stack of conventional sheet-pile cells ( 14 ), filled with materials normally selected for a structure according to the prior art, are located on either side of the stack of protective sheet-pile cells ( 25 ).
In a fourth embodiment (see FIG. 9 ), the structure ( 25 ) includes a stack of sheet-pile cells according to the first embodiment of FIG. 1 and according to the fourth embodiment of FIG. 4 . This embodiment may also be constructed from an alternation of sheet-pile cells filled with materials normally selected for a structure according to the prior art and of sheet-pile cells according to the third embodiment of FIG. 3 .
In a fifth embodiment (see FIG. 10 ), the structure ( 26 ) has a solid structure formed by an embankment ( 27 ), for example consisting of earth, reinforced uniformly over its entire height with reinforcing sheets ( 28 ) in geotextile or geosynthetic form or in the form of metal latticework or gridwork. The reinforcing sheets ( 28 ) extend only over part of the thickness of the embankment ( 27 ). An inclined protective facing ( 29 ), which is or is not secured to the main structure of the structure, is produced by means of a plurality of longitudinal elements in one piece which conform to the first embodiment of FIG. 1 or to the third embodiment of FIG. 3 . The outer part ( 30 ) of the facing ( 29 ) may consist of pebbles or of topsoil or of a soil/pebble mixture which is then established with plants.
In a sixth embodiment (see FIG. 11 ), the structure ( 31 ) likewise comprises an embankment ( 27 ), consisting, for example, of earth, reinforced uniformly over its entire height with reinforcing sheets ( 28 ) in geotextile or geosynthetic form or in the form of metal latticework or gridwork. The reinforcing sheets ( 28 ) in this case extend over the entire thickness of the embankment ( 27 ). The stability of the two faces is ensured. An inclined protective facing ( 32 ) is produced by means of a plurality of longitudinal elements in one piece which conform to the third embodiment of FIG. 3 . The outer part of the facing ( 32 ) may consist of pebbles or of topsoil or of a soil/pebble mixture ( 33 ) which is then established with plants.
In a seventh embodiment (see FIG. 12 ), the structure ( 34 ) is an embankment ( 27 ), consisting, for example, of earth, reinforced uniformly over its entire height with reinforcing, sheets. ( 28 ) in geotextile or geosynthetic form or in the form of metal latticework or gridwork, which extend only over part of the thickness of the embankment ( 27 ), so as to ensure the stability of the slope. The local stability of one of the faces is ensured with the aid of sheet-pile cells ( 14 ) filled with materials normally selected for a structure according to the prior art. A protective facing ( 27 ) is produced by means of sheet-pile cells ( 1 ) according to the first embodiment of FIG. 1 .
In an eighth embodiment (see FIG. 13 ), the structure ( 38 ) consists of a vertical stack of sheet-pile cells ( 14 ) filled with materials normally selected for a structure according to the prior art, the said stack being laid against an embankment ( 27 ) reinforced with reinforcing sheets ( 28 ) in geotextile or geosynthetic form or in the form of metal latticework or gridwork, extending over the entire thickness of the embankment ( 27 ), so as to ensure the stability of the slope on either side. A substantially vertical protective facing ( 39 ) is produced by means of sheet-pile cells according to the first embodiment of FIG. 1 , but inverted, with their front volume filled with elastoplastic materials.
In a ninth embodiment (see FIG. 14 ), the structure ( 40 ) consists of a vertical stack of sheet-pile cells ( 14 ) which is laid against an embankment ( 27 ) reinforced with geotextile or geosynthetic sheets ( 28 ) or metal latticework or gridwork, extending over the entire thickness of the embankment ( 27 ), so as to ensure the stability of the slope on either side. An inclined protective facing ( 41 ), substantially similar to the facings of the fifth and sixth embodiments of structures (see FIGS. 10 and 11 ), is produced by means of a plurality of longitudinal elements in one piece which conform to the first embodiment of FIG. 1 .
The present invention is not limited to the embodiments described and illustrated. Many modifications may be made, without thereby departing from the framework defined by the scope of the set of claims.
The dimensions of the protective sheet-pile cells may be highly variable as a function of the desired protective structure. Other uses may be considered, such as protective structures in the military field or structures for the reinforcement of banks of canals, streams, rivers and seashores, where the moveable masses are objects transported by the flow of water, or even traffic routes for the protection of vehicles from impacts. | A civil engineering structure, intended for ensuring protection against impacts of moveable masses, has a face exposed to the impacts of moveable masses. The structure includes, in the region of the face exposed to the impacts of moveable masses, a set of individual construction elements secured to one another and filled completely or partially with at least one material having a capacity for being deformed elastoplastically, the individual construction elements liable to be damaged by impacts of moveable masses being capable of being replaced individually by similar individual construction elements. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to weighing machines, and in particular to storage hoppers which receive and discharge product to be weighed in the course of weighing operations. Such hoppers, for example, may be a weighing hopper which is coupled to a transducer to generate a weight signal for subsequent processing. The storage hopper is especially useful in combination weighing machines in which a plurality of the hoppers receive and discharge product in a cyclic operation to generate charges of product for packaging.
Weighing machines which are commonly used in packaging operations generally include a plurality of weighing hoppers which periodically receive product to be weighed and discharged after a weight measurement has been taken. U.S. Pat. No. 2,387,585 illustrates a conventional packaging machine in which the weighing hoppers are an integral part of the charge-forming operation. More recently combination weighers of the type shown in U.S. Pat. No. 4,466,500 have assumed the charge-forming and weighing functions because of the high speed at which the machines can operate without reducing the accuracy of the weighing function. In combination weighers a plurality of weighing hoppers are used to continuously weigh small quantities of product, and the quantities are then combined in selected combinations to form charges of product closely approximating a given target weight.
In all types of weighing machines which generate signals indicative of the measured weight, it is preferable that such signals represent as much of the weight of product as possible and as little of the weight of the hopper as possible. For this reason range springs such as shown in U.S. Pat. No. 4,550,792 are sometimes added to the support mechanism for the hopper to carry a substantial portion of the "dead" weight of the hopper. Thus, the weight of the hopper does not appear in the signal derived from the strain gauge or other weight sensor and the total weight capacity of the sensor is confined to the range of product weights anticipated. Unfortunately, however, range springs are not permitted by many government or administrative regulations and, without other counterbalances for the dead weight of the hopper, as little as 20% of the weight signal may represent the useful load of product. Since the errors due to hysteresis and linearity are dependent on the total weight signal from the sensor, significant error can remain in the product weight component after the dead weight component has been subtracted.
In many weighing machines the hoppers frequently have a construction with the support structure, door hinges and operating linkages secured or suspended from the body. Examples of such hoppers are shown in U.S. Pat. Nos. 4,398,612 and 4,635,831 and 4,874,048. With a construction and hopper assembly of this type, the body itself must have a heavy gauge metal sufficient to carry the bearing loads and stresses that arise from the associated loads carried by the other structure and mechanisms. Such hopper structures are, therefore, relatively heavy structures and contribute to a significant portion of the weight measurements. The same hopper structures inhibit the use of different and less expensive materials, and are costly to manufacture due to the materials used and the polishing and other work that is needed for a sanitary finish.
In other designs, the hoppers have a partial frame for supporting the hopper body in part. Such hoppers are shown in U.S. Pat. Nos. 4,499,962, 4,527,647 and, 4,545,446. The partial frames reinforce the hopper body and thereby allow some reduction in weight through lower gauge metals, but still allocate some of the load bearing functions to the body. With such designs, the bodies must have sufficient strength to carry loads other than those from the weight of product, and the bodies and reinforcing frames are integrated structures inseparable from one another.
A further requirement of many weighing machines having a plurality of hoppers is ease of inspection, maintenance and disassembly for cleaning. For example, customers often specify that the hoppers must be removable from the weighing machine without tools. In accordance with these design requirements, weighing machines have releasable couplings between the hoppers and the machine frames. Examples of such hoppers and their couplings are shown in U.S. Pat. Nos. 4,398,612, 4,499,962 and 4,527,647. Because of the environment and the constant state of vibration that exists when such hoppers are operating, it is essential that the couplings hold the scales rigidly and securely to the machine. The objectives of a secure and rigid fastening along with ease of disassembly are generally in conflict and accordingly designing such couplings is a formidable task.
To minimize the "dead" weight of a hopper and at the same time to permit the hopper to be readily disassembled from the machine, it is customary to mount the actuating mechanism for opening and closing a discharge door on the frame of the machine and to transmit the driving motions to the door through an interrupted linkage. In this fashion the weight of the actuator does not become part of the sprung weight of the hopper. Examples of interrupted linkages are shown in U.S. Pat. Nos. 4,499,962, 4,527,647, 4,635,831 and 4,874,048. In such linkages the actuator is a uni-directional actuator which simply pushes one end of the operating rod against an operating linkage to cause the door to open, and a spring mechanism connected with the operating linkage returns the door to the closed position. Consequently, the spring is relied upon to hold the door closed and locked in opposition to the weight of product and the impact loads arising when product falls into the hopper.
It is accordingly a general object of the present invention to provide a weigh hopper which has a construction which allows different and lighter materials to be used in the non-stressed portions of the hopper so that the hopper has less weight and can be constructed for removability and at substantial cost saving over the conventional construction methods.
It is a further object of the present invention to provide a quick-release coupling which maintains the hopper rigid and securely connected to the machine frame during weighing operations and which releases the hopper from the machine frame simply and without tools when necessary for cleaning, repair or inspection.
It is still a further object of the present invention to provide a hopper with a discharge door and operating linkage that is easily released during hopper removal and, at the same time, securely closes and locks the door during cyclic filling and discharging operations.
SUMMARY OF THE INVENTION
The present invention resides in a storage hopper for receiving and discharging product in a weighing machine.
In one aspect of the invention, the hopper is constructed with a chassis or frame having a mounting for supporting a separate hopper body that receives and holds product until discharge. The hopper body includes mounting means for joining the body to the mounting of the hopper chassis and thus permits the body and the chassis to be constructed from different types of materials. For example, the chassis may be a heavy gauge steel while the body is made of light weight aluminum sheet metal or molded plastic. The mounting means on the body and the mounting on the hopper include a releasable coupling for removing the hopper or substituting another hopper. At least one discharge door connected with the assembled hopper body and chassis moves between a closed position in which the product is retained within the hopper and an open position for discharging product from the hopper.
In another aspect of the invention, a releasable coupling is employed for installing and removing the hopper in the weighing machine. The coupling includes a pair of hanger brackets which project laterally from the machine in spaced and parallel relationship. Each bracket has a hook on an upper part from which the hopper is suspended and two offset abutment tabs on the lower part. The hanger plate connected with the hopper has a notch in a lower edge which extends upwardly a distance equal to the distance between the hook and tabs on the hanger brackets. The notch is also defined by parallel side edges which are spaced to straddle the parallel brackets in close fitting relationship within slots that are formed between the tabs of the brackets. In this fashion the hopper is constrained against all movement other than lifting movement for quickly releasing the hopper from the machine.
In still a further aspect of the invention, a storage hopper used for receiving and discharging a product in a weighing machine has a hopper container with a discharge opening in a lower portion of the container for discharging product, and a discharge door pivotally mounted to the hopper container adjacent the discharge opening. The door is movable between an open and closed position by means of an operating linkage. The linkage includes a pair of toggle links that extend between a pivot point on the container and a pivot point on the door, and the links move through a toggle position to lock the door in the closed position independently of other operating mechanisms.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a combination weighing machine having a plurality of weigh scales that include hoppers constructed in accordance with the present invention.
FIG. 2 is a perspective view of a hopper actuator and hopper from a weigh scale in FIG. 1 with the body shell lifted off of the hopper chassis.
FIG. 3 is a right side elevation view of the hopper and quick-release coupling shown in FIG. 2 and the hopper suspension and weight sensors of a weigh scale.
FIG. 4 is a front elevation view of the hopper in FIG. 2.
FIG. 5 is a left side elevation view of the hopper in FIG. 2.
FIG. 6 is a fragmentary side elevation view showing the quick-release coupling in FIG. 2.
FIG. 7 is a fragmentary plan view of the quick-release coupling in FIG. 6.
FIG. 8 shows a toggle link with a compliant link portion in section.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a combination weighing machine, generally designated 10, which employs the hoppers of the present invention to produce a charge of product closely approximating a target weight. Products handled by the machine vary widely from finely divided foods such as candies or nuts to fruits, vegetables, frozen chicken parts and many non-food products, all of which must be generally flowable to pass through feeders and a discharge chute to a packaging machine below. In accordance with conventional combination weighing techniques, the machine 10 determines the weights of multiple quantities of the product and then selects a combination of the quantities having a total weight most closely approximating the target weight, and generally not less than the target weight, for discharge.
The combination weighing machine 10 has a frame 12 and a plurality of weigh scales 14 distributed in a circular array about a central, vertical axis of the machine. Each of the scales has an associated dump chute 16 which guides product discharged from the scales into a collector chute 18 for discharge into the associated packaging machine (not shown).
A bulk feed conveyor 20 at the top of the machine 10 delivers product from a storage bin (not shown) and keeps a supply of product available in a conical distribution tray 22 centrally above the circular array of weigh scales 14. Both the conveyor 20 and the tray 22 are provided with controlled vibrators to insure movement of the flowable product as needed into the machine.
A plurality of accumulator hoppers are distributed in a circular array about the distribution tray 22 and each hopper 24 receives product from the tray through an intermediate vibratory feeder (not shown). The accumulator hoppers are fed with a quantity of product which is coarsely equivalent to a fraction of the target weight. For example, the vibratory feeders may be selected to operate for a fixed period of time at a given amplitude to deliver between 1/3 and 1/4 of the product expected to be discharged from the combination weighing machine at the target weight. When a weigh scale 14 has dumped its charge of product into the collector chute 18, a waiting quantity of product in the associated accumulator hopper is dumped to refill the empty hopper of the weigh scale. Since the precise target weight of the product delivered to the packaging machine is achieved through the combination search and selection process, it is not necessary that the weight of product fed from the accumulator hoppers 24 to the weigh scales be precisely controlled. The weights need only be known with accuracy for the combination search and selection process. In fact, random variations in the weights are desired for selection of acceptable combinations.
In accordance with the present invention, FIG. 2 shows a storage hopper 30 and a bi-directional actuator 32 from one of the weigh scales 14 in FIG. 1. The hopper 30 receives a quantity of product to be weighed and stores that quantity of product until the quantity is selected to form a charge of product discharged to a packaging machine. The hopper is comprised basically of a hollow body shell 34, a chassis or frame 36 on which the body shell is mounted, a pair of discharge doors 38, 40 and a door operating linkage 42. In accordance with one aspect of the invention, the body shell is a separate component that can be removed for cleaning, inspection, and repair or alternatively, the body shell can be replaced with another body shell of different shape, volumetric capacity or material. In this manner different types of products can be handled by the weighing machine with a standardized chassis and operating mechanism for the discharge doors.
The pair of opposed and cooperating discharge doors 38,40 are mounted on the chassis 36 for pivotal movement between opened and closed positions. While it is necessary to have at least one discharge door for each hopper 30, two doors are shown in the illustrated embodiment to insure a rapid dumping of the product in the hopper when the quantity has been selected for discharge by the machine.
The hollow body shell 34 illustrated in the drawings has a flared opening at the top 48 for receiving product from the accumulator hopper above, an opening at the bottom 50 through which product is discharged when the doors 38, 40 are opened and a hollow passageway between the openings at the top and bottom through which all of the product to be weighed passes in a sequence of weighing and dumping operations. Naturally, the product is stored within the hollow body during the interval in which the flanged discharge doors 38,40 are closed. For this purpose, the bottom 50 of the body shell has angularly disposed edges 52 on two opposite sides 54,56 of the generally rectangular shell, and the angle of the edges 52 is cut to match the positions of the discharge doors in the closed position. Hence the weight of the product in the body shell will, for the most part, rest on the discharge doors, and the body shell 34 need only have sufficient strength to contain the product in a column within the body. The shell, therefore, can be constructed of a relatively light weight material, such as a thin gauge sheet metal or plastic. Correspondingly, the chassis 36 which supports the weight of product as well as the rest of the hopper 30 including the pivotally connected doors 38,40 and operating linkage 42 may be constructed with a heavier gauge metal in accordance with the prior art structures.
Therefore, one of the principal advantages of the hopper 30 with a separate body shell 34 and chassis 36 is that the hopper overall has a lighter weight and permits the use of lower range weight sensors. Lower range weight sensors lead to greater accuracy of weight readings since linearity and hysteresis are a percent of the total weight capacity of the weigh scale, and the weight of the product in the scale represents a higher portion of the total weight measurement. Correspondingly, with the lighter body shell, the total dead weight of the scale represents a smaller portion of the weight measurement.
The chassis 36 of the hopper 30 defines a generally rectangular passageway or opening corresponding to the cross section of the body shell 34, and the sides of the shell 34 fit telescopically within the frame opening so that product passing through the shell also passes through the chassis during discharge. In addition to the telescopic arrangement of the shell and chassis, a three-point mounting arrangement including three mounting pins and brackets 60,62 (two visible) mate with corresponding holes, 64,66 (two visible) in the chassis 36. The mating pins and holes comprise releasable couplings which allow the body shell to be easily removed from the chassis 36 for cleaning, repair or substitution of other body shells. The mounting pins 60,62 have snap-type fittings or releasable spring clips so that the body shell 34 cannot come loose on the chassis 36 when the pins are inserted in the holes 64,66. The removable body shell without tools has a very simple, light weight construction with a smooth interior because all of the complicated mechanical structures including pivot points and load bearing linkages and members are confined to the chassis 36.
FIGS. 2 and 3 illustrate a quick-release coupling, generally designated 70, for installing, retaining and removing the hopper 30 in a weighing machine. Such couplings are generally required in most food weighing machines due to the frequency with which the machines must be disassembled for cleaning.
The coupling 70 connects the hopper 30 with the weight measuring portion of the weigh scale, including the strain gauge sensor 72 in FIG. 3. The sensor is mounted on a scale base 74 fixed to the machine frame 76 and is coupled to the hopper mount 78 which is resiliently suspended from the scale base by a pair of flexible leaf springs 80. A dash pot 82 for damping vibrations of the scale and a reference weight 84 for calibrating the scale readings may also be mounted on the scale frame 74.
FIGS. 2, 6 and 7 illustrate the quick-release coupling 70 in greater detail. The coupling 70 is a two-part structure having a hanger 90 which is secured to the hopper mount 78 and a hanger plate or bracket 92 which is secured to the hopper chassis 36. The hanger 90 is a U-shaped bracket plate and is comprised of two hanger brackets 94,96 which project outwardly from the weighing machine in spaced and parallel relationship. Each bracket includes on its upper part a hook 98 or 100 on which the hanger plate 92 is suspended. Each bracket also includes a set of abutment tabs 102,104 or 106,108 on the lower part of the bracket, and the tabs project laterally of the brackets. The tabs are positioned in a stepped relationship and define a slot between them which is directly below the valley of the hook 98 or 100 above so that the hanger plate 92 when suspended from the hook extends downwardly through the slot with the tab 102 on one side of the plate and the tab 104 on the opposite side of the plate as shown most clearly in FIGS. 6 and 7.
The hanger plate 92 has a rectangular notch extending upwardly from its lower edge a distance equal at least to the distance between the valley of the hook and the tabs on the hanger bracket and defines a bar 109 along the top of the notch. The parallel side edges 110,112 of the notch are spaced by the same amount as the hanger brackets 94,96 to straddle the brackets in close fitting relationship. With this arrangement the hopper is stabilized against rotation about all three coordinate axes by the quick-release coupling and will remain securely suspended from the weighing machine. In spite of the secure suspension, however, the hopper 30 can be easily lifted off of the hanger brackets for cleaning or servicing as needed.
The operating linkage 42 which opens and closes the discharge doors 38 and 40 on the hopper is supported on the chassis 36 along with the doors so that the hopper body shell 34 can be removed without disturbing or uncoupling the linkage. The operating linkage includes a pair of toggle links 120,122 which are self-locking to hold the doors in the closed position shown in FIG. 2 and in the solid-line positions of FIGS. 3 and 5. The toggle link 122 is one lever arm of a bell crank pivotally connected to the chassis frame above the door 40, and the toggle link 120 is pivotally connected at one end to the link 122 and at the opposite end to the other door 38. A second lever arm 124 of the bell crank is connected with the operating rod 130 of the bi-directional actuator 32 (FIG. 2). The connection is accomplished by means of a rigid yoke formed by the lever arm 124, a transverse bar 126 and a parallel arm 128 on the side of the hopper opposite from the arm 124. The operating rod 130 has a forked end 132 that straddles the transverse bar 126 when the hopper is suspended from the hanger 90.
The opening and closing motion of the doors produced by the toggle links 120,122 is applied directly to the door 38 by the link 120 and is transmitted from the door 38 to the door 40 through a transfer link 144 on the opposite side of the hopper 30 as shown in FIG. 5. Thus, the opening and closing movements of the doors 38,40 are coordinated and generated from the single bi-directional actuator. In the preferred embodiment the actuator is a reversible servomotor.
The toggle links 120,122 are shown in FIG. 3 in two extreme positions corresponding with the discharge doors 38,40 open and closed respectively. During operation the toggle links pass through the toggle position, that is when the links are precisely aligned with one another, shortly before the doors reach their fully closed position. To ensure locking in the closed position and to relieve stress as the links pass through the toggle position, a compliant link portion 142 of the link 120 provides a limited degree of compliance when the link is under compression.
The detailed structure of the link 120 and compliant link portion 142 is illustrated more particularly in FIG. 8. The link 120 has a spherical rod end bearing 150 for connection with the link 122 and a spherical rod end bearing 152 for connection with the discharge door 38. The rod end bearing 150 is threadibly secured to a shaft 154 that passes through a cylinder plug 156 and an internal thrust washer 158. Lock nut 160 secures the rod end bearing at one end of the shaft 154 and two jam nuts 162 secure the washer 158 at the other end of the shaft. The cylinder plug 156 is threadibly engaged in one end of a cylinder 166, and clamps the washer 158 between the plug and a compression spring 168 captured within the cylinder 166. The relaxed length of the compression spring 168 is somewhat larger than the free space allotted in the cylinder by the plug so that the compression spring is under a slight preload and maintains the link 120 rigid up to the preload level. The rod end bearing 152 is secured to the end of the cylinder 166 by means of two jam nuts 170, a short shaft 172 and the lock nut 174.
The length of the toggle link 120 is adjusted to be slightly longer than the distance between the link 122 and the door 38 in the closed position so that the compliant link portion 142 actually holds the toggle linkage in the solid-line position shown in FIG. 3 due to the slight compressive force applied by the coil spring 168 within the compliant link portion. Thus the spring pressure holds the toggle linkage and the discharge doors locked in the closed position.
To open the doors the operating rod of the bi-directional actuator 32 must positively push against the rigid yoke formed by the toggle link 120 and move the links from the locked position through the toggle position to the open position of the links and the doors 38,40. As the toggle links 120,122 pass through the toggle position, the compression spring 168 is additionally compressed by a slight amount which relieves some of the stress and strain that would otherwise be applied to the links, the doors and the chassis. Thus in the closed position the links 120,122 have passed slightly beyond the toggle position and effectively lock the doors in the closed position. The coil spring 140 extending between the junction of the two links and the chassis is always in tension and insures that the links and doors are urged toward the closed position, but the spring is not essential.
When the command is given to discharge the quantity of product in the hopper 30, the operating rod 130 is pushed toward the hopper and causes the links to rotate from the locked or closed solid-line position through the toggle position to the unlocked or open position illustrated in phantom in FIGS. 3 and 5.
To close the doors, the operating rod 130 is positively pulled away from the hopper 30 by the bi-directional actuator 32, and the toggle links 120,122 are pulled through and slightly passed the toggle position to move further into the locking position with the doors closed. The slight compression load in the compliant link portion 142 of the link 120 holds the toggle links and the doors in the closed position. Thus the actuator 32 must be bi-directional in order to move the linkage in both directions through the toggle position for opening and closing the doors.
While the present invention has been described in a preferred embodiment, it should be understood that numerous modifications and substitutions can be made without departing from the spirit of the invention. For example, it is not essential that the hollow hopper body 34 fit telescopically within the frame 36. The body can be secured by any means on the chassis provided that the passageways between the hopper and chassis are in registration for receiving and discharging product. Although the body has been described in conjunction with a weigh scale, the hollow hopper body and separate frame can also be used for the accumulator hoppers or other hoppers on the weighing machine. As mentioned above while two doors have been shown for discharging product from the hopper, one door may suffice and the operating linkage employing two toggle links can be employed with the same advantage to hold the single door closed in a locked position of the linkage. The notch in the hanger plate 92 can be formed by two parallel slots that straddle the parallel hanger brackets 94,96 respectively with equivalent effects. Accordingly, the present invention has been described in several preferred embodiments by way of illustration rather than limitation. | A hopper for receiving and discharging product in a weighing machine has a construction comprised by a removable body shell and a supporting chassis. The shell has an opening at the top for receiving product to be weighed and an opening at the bottom for discharging the product after weighing. A discharge door cooperates with the opening at the bottom of the shell body to support the weight of product within the shell during weighing and to discharge the product after weighing. A quick-release coupling permits the hopper to be firmly installed on the weighing machine and to be quickly removed from the machine without tools. A toggle linkage is employed to operate the discharge door and locks the door in the closed position without further locking mechanisms. A bi-directional actuator moves the toggle linkage and door into and out of the closed position. | 6 |
FIELD OF THE INVENTION
The present invention relates generally to the access of distributed computing network environments and more specifically to a method and systems for sharing Internet network access points across Internet Service Providers.
BACKGROUND OF THE INVENTION
Recently, communication between computer systems for data and information exchange has been significantly developing thanks to the Internet, which is known to have rapidly spread on a global level by virtue of being supported by public communication networks, both traditional and technologically advanced ones, such as ISDN, ADSL, GPRS, and others.
Success of this phenomenon is indeed due, also, to the availability, in real time and cheaply, of information and data stored on servers located all over the globe and connected through dedicated digital lines to computers reachable through the various last mile network access services.
As regards the cheapness of operations practicable on the net, it has to be considered that it is directly bound to the cost of the access connection between the user's computer and the access point to the net. More exactly, the network access points are identified, for example by telephone numbers which are made available to the users by each Internet Service Provider (ISP), in order to allow the connection to the provider computers, which are part of the network. As it is known, they store all users' identification data and offer services such as electronic mail, access to sites of the net by assisted, or not, research procedures, memory spaces where each user can put data, commercial news or other information news visible to all users of the net, and more other services.
Thanks to the quality and variety of these services, and also to growing variety of technical tools for access to the net, such as computers, advanced means interfacing TV sets, mobile telephone apparatuses, etc., the number of Internet users has been rapidly increasing. Therefore, it is easily understandable how it can become important to get fast connections to the net through affordable access points, that is, points included in the user's telephone district or area, or in very near areas.
In order to better understand the above difficulties, it has to be considered that according to current connection modalities the user has to choose a specific Internet Service Provider identifying the user according to specific identification data, said Internet Service Provider being associated to an access number, for example a telephone number, stored in memory means of the user's connecting apparatuses to the net. This access number must expediently coincide with the provider's nearest access points to the place where the connecting apparatuses are.
FIG. 1 illustrates schematically the accessing of data on Internet network 100 , a distributed computing network environment. The participants in the Internet are a wide variety of machines, organizations, and individuals, all able to communicate and share information. For example, the Internet network 100 includes a plurality of Internet sites 105 - 1 to 105 - q . These Internet sites are generally operated by corporations, universities, and governmental organizations. Each Internet site may include one or more repositories of information and resources that may be accessed over the Internet. Each Internet site, e.g., 105 - 1 and 105 - q , may include a plurality of WEB servers e.g., 110 - 1 to 110 - r and 110 ′- 1 to 110 ′- n , respectively. Each of these WEB servers may provide a “home page” to be visited, files to be read or downloaded, applications to be shared, and the like.
The Internet network 100 also includes a plurality of points of presence (POPs) 115 - 1 to 115 - s that are operated by Internet service providers (ISPs). These ISPs are in the business of providing Internet access to end-user stations, generically referred to as 120 . As mentioned above, the costs of the telephone connection between a user's computer and the access point to the net represent an important part of the Internet connection costs and thus, the geographical locations and distributions of the POPs 115 - 1 to 115 - s are important. For sake of illustration, it is assumed that POPs 115 - 1 to 115 - 3 belong to a first geographical location, referred to as 125 - 1 , and POP 115 - s belongs to a second geographical location, referred to as 125 - 2 .
As it is apparent from FIG. 1 , two problems may arise when a user needs to set a connection with the ISP the user has a supplying contract with. Firstly, if the POP of the ISP is located in the second geographical location 125 - 2 while the user is momentarily located in the first geographical location 125 - 1 , the communication costs between the user and the point of presence may be prohibitive. Secondly, if the closest POP is over-busy, the user must choose another POP, farther away, which increases communication costs. For example, if POPs 115 - 3 and 115 - s belong to a same ISP and the user is located in the first geographical location 125 - 1 , the user may be forced to set its connection with POP 115 - s when POP 115 - 3 is over-busy. This case may arise even though POPs 115 - 1 and 115 - 2 are not over-busy since these POPs may belong to other ISPs.
Likewise, the subscribers of ISPs that do not have enough POPs may experience difficulties establishing connections.
These problems may be avoided by improving geographical distribution of POPs and increasing the number of POPs for each ISP. However, this is not realistic due to the required expenses. As a result, there is a need for a method and systems for sharing points of presence between Internet service providers.
SUMMARY OF THE INVENTION
Thus, it is a broad object of the invention to remedy the shortcomings of the prior art as described above.
It is another object of the invention to provide a method and systems for sharing network access capacities across Internet service providers wherein the security level of Internet service providers is maintained.
It is a further object of the invention to provide a method and systems for sharing network access capacities across Internet service providers wherein the duration of using the shared access capacities, or the number of connections that are established simultaneously, based on shared access capacities, is automatically evaluated.
It is still a further object of the invention to provide a method and systems for controlling shared network access capacities across Internet service providers.
It is still another object of the invention to provide a method and systems for sharing network access capacities across Internet service providers wherein an access request destined to a first service provider is automatically transferred to a second service provider when the access points of the first service provider are over-busy.
The accomplishment of these and other related objects is achieved by a method for sharing network access capacities between a master service provider, comprising at least one point of presence, and a client service provider, said method comprising the steps of:
upon reception of an access request, including at least a subscriber identifier, a service provider identifier and a password, at said at least one point of presence:
determining, according to said service provider identifier, if said access request comes from a subscriber of said master service provider or from a subscriber of said client service provider, said access request being rejected otherwise; if said access request comes from a subscriber of said master service provider,
determining, using said subscriber identifier and said password, if said subscriber is authorized to establish a connection; and, if said subscriber is authorized, establishing a connection, else, rejecting said access request;
else, if said access request comes from a subscriber of said client service provider,
determining if a new connection may be established for a subscriber of said client service provider; and, if a new connection may be established, sending an authorization request, comprising at least said subscriber identifier and said password, to said client service provider else, rejecting said access request;
upon reception of an authorization acknowledgment, comprising said subscriber identifier, from said client service provider:
if said subscriber is authorized, establishing a connection else, rejecting said access request
Further advantages of the present invention will become apparent to the ones skilled in the art upon examination of the drawings and detailed description. It is intended that any additional advantages be incorporated herein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates schematically the accessing of data on the Internet network, wherein the invention could be implemented.
FIG. 2 shows schematically the authentication, authorization and accounting mechanism in the master and client service providers when access requests are received.
FIG. 3 illustrates an example of the algorithm used for establishing a connection between a subscriber and a master service provider's point of presence.
FIG. 4 depicts schematically the implementation of the invention when using RADIUS protocol.
FIG. 5 illustrates an algorithm that may be used in the RADIUS proxy of the invention.
FIGS. 6 to 9 show timing analysis examples of a connection process based on the algorithm of FIG. 5 .
DETAILED DESCRIPTION OF THE INVENTION
According to the invention, a Service Provider, typically an Internet Service Provider (ISP) or Application Service Provider (ASP), referred to as “Master SP” or MSP in the following description, owning a large infrastructure, could rent out part of its network access capacity to a third party service provider, referred to as “Client SP” or CSP, having its own infrastructure, that requires additional capacity at peak times or needs to increase geographical coverage through additional Points Of Presence (POP). To maintain a constant security level and provide connection billing basis, the invention is based on the following items:
the Master SP identifies incoming access requests into its network which are really meant for the Client SP in order to route the session appropriately; the master SP send a request to the Client SP to check authorization of Client SP's subscribers upon incoming access requests of these Client SP's subscribers (information of Client SP's subscribers are not memorized in the Master SP databases) the Master SP tracks sessions coming in through its POP's and meant for the Client SP in order to bill the Client SP based on actual usage. Usage data collection supports flexibility for the subsequent billing step, which can occur, for instance, based on:
fixed Fee contract based on fixed capacity allocation for simultaneous connection; total connection time within a defined period of time;
the Master SP controls in real-time the capacity allocated to its Client SP's to prevent impact on the quality of the service offered to its own subscribers; the Client SP retains the same level of control and ownership on its subscribers' sessions whether they come in through its own or through the Master SP POP.
The main principle of the invention consists in the creation of a “Virtual Subscriber” that represents Client SPs in the Master SP system, as illustrated in FIG. 2 . FIG. 2 illustrates schematically the Authentication, Authorization and Accounting mechanism (AAA) in the Master and Client SPs when access requests are received. Master SP 200 comprises a POP 205 , an AAA mechanism 210 , a database 215 containing information about its subscribers and a database 220 for virtual subscriber, i.e., Client SPs. Likewise, Client SP 225 comprises a POP 230 , an AAA mechanism 235 and a database 240 containing information about its subscribers. A standard Client SP does not contain a database for virtual subscribers. However, it should be noted that a SP may be simultaneously a Master and a Client SP. In such case, the Client/Master SP contains a database for virtual subscribers, i.e., Client SPs of the Client/Master SP.
When a Master SP's subscriber 245 - 1 requests access to Master SP 200 through POP 205 , or when a Client SP's subscriber 245 - 2 requests access to Client SP 225 through POP 230 , AAA mechanisms are used as standard. In such a case, the POP sends a request to the AAA module that compares subscriber information, e.g., subscriber identifier and password, with the ones stored in the subscriber database. If information matches, the connection is established, else, the connection is rejected.
FIG. 3 illustrates an example of the algorithm used for establishing a connection between a subscriber 245 - 1 or 245 - 2 and a POP of the Master SP's 200 , according to the invention. When the Master SP 200 receives an access request, a first test is performed to determine if it comes from a Master SP's subscriber (box 300 ), using the database 215 of Master SP's subscribers. If the access request comes from a Master SP's subscriber, a connection is established (box 325 ) after this subscriber has been authenticated and authorized. This authentication/authorization is a standard authentication/authorization process, e.g. verifying the password associated to the subscriber identifier using the database 215 . Connection parameters may be memorized in database 215 for billing operations or to perform statistics. If the access request does not come from a subscriber of the Master SP, a test is performed to determine whether or not it comes from a subscriber of a Client SP (box 305 ). This test is done by using the database 220 of the virtual CSPs, by analyzing the subscriber's realm (Master SP does not memorized information relative to Client SP's subscribers). If the realm of the subscriber does not correspond to any Client SP, the access request is rejected. Else, a new test is performed to determine whether or not a subscriber of the corresponding Client SP can establish a connection from the Master SP (box 310 ). This test, based on the Virtual SP's status, consists in checking access capacities allocated to Client SP 225 , e.g., is there enough free ports for the CSP, has the CSP not exceeded his credit threshold, has the MSP not suspended business with CSP? Such Virtual SP's status is memorized in database 220 . If a connection is not allowed for reasons related to the Client SP, access request is rejected.
Else, if a connection is allowed, another test is performed to authenticate the subscriber and determine if Client SP authorizes the connection (box 315 ). To that end, the Master SP sends a request to the Client SP with the information received in the subscriber's request e.g. subscriber identifier and password. As mentioned above, information relative to Client SP's subscriber is not stored in any Master SP database and thus, the Master SP can not authenticate Client SP's subscribers. Using its database 240 , the Client SP authenticates the subscriber having sent the access request to the Master SP and forewarns the Master SP whether or not the authentication succeeds. Such authentication process is standard. If the subscriber is not authenticated, the connection is rejected. Else, connection parameters are stored in the database 220 of the virtual SP (box 320 ) and the connection is established (box 325 ). These parameters may comprise, for example, the number of connections established for the same Client SP and the connection duration, for purpose of billing Client SP and maintaining the quality of service offered to Master SP's subscribers. On its side, the Client SP stores similar information, relative to the subscriber, for billing subscribers.
Even though Client SP is identified using the realm of the subscriber having sent the request in the previous description, other means may be used such as using the called-number or the name of the network access server when a called-number or a network access server are dedicated to the connection of Client SP's subscribers.
The implementation of the invention may be based on the RADIUS protocol, by creating a RADIUS proxy between the Master SP POP, containing the RADIUS Client, and the Master SP RADIUS server and Client SP RADIUS server, as illustrated on FIG. 4 . The RADIUS protocol is described, for example, in “Remote Authentication Dial In User Service (RADIUS)” (Rigney, C., Willens, S., Rubens, A. and W. Simpson, RFC 2865, June 2000) and “RADIUS Accounting” (Rigney, C., RFC 2866, June 2000).
Turning now to FIG. 4 which illustrates schematically the implementation of the invention when using RADIUS protocol, it is shown the Master and Client SPs 200 and 225 as well as MSP and CSP subscribers 245 - 1 and 245 - 2 of FIG. 2 . Master SP 200 comprises the POP 205 that includes a set of Network Access Servers (NAS), generically referred to as 400 . Each NAS 400 controls a plurality of modems (not represented for sake of clarity) that interface subscriber systems to Master SP 200 . In this implementation example, each NAS 400 comprises a RADIUS client, generically referred to as 405 , to handle subscriber requests. A RADIUS proxy 410 links RADIUS clients 405 to a Master RADIUS server 415 and a Client RADIUS server 430 . RADIUS proxy 410 determines which RADIUS server must be accessed. Likewise, Client SP 225 comprises the POP 230 that includes a set of NAS, generically referred to as 420 , that interface subscriber systems to Client SP 225 . Still for sake of illustration, each NAS 420 includes a RADIUS client, generically referred to as 425 . Client RADIUS server 430 may be access either by RADIUS clients 425 or RADIUS proxy 410 .
FIG. 5 depicts an algorithm that may be implemented in RADIUS proxy 410 . When an access request is received from a RADIUS client 405 , a first test is performed to determine whether or not the request is received from a Master SP's subscriber (box 500 ). If the request has been sent by a Master SP's subscriber, the request is transmitted to the Master RADIUS server 415 (box 505 ). Upon reception of an authentication acknowledge from the Master RADIUS server (box 510 ), a second test is performed to determine whether or not the subscriber has been authenticated (box 515 ). If the subscriber has not been authenticated, the access request is rejected, else, another test is conducted to determine if the subscriber is a Master SP's subscriber or not (box 520 ). If the subscriber is a Master SP's subscriber, the connection is established and accounting may start (box 525 ).
If the access request has not been sent by a Master SP's subscriber (box 500 ), the access request is copied and modified (box 530 ). The modification of the access request comprises the step of removing the subscriber identifier and password that are replaced by a virtual subscriber identifier and password. A couple of virtual subscriber identifier and password is assigned to each Client SP of the Master SP 200 , according to the realm. Then, the modified access request is transmitted to the Master RADIUS server 415 (box 535 ). Upon reception of an authentication acknowledgment from the Master RADIUS server (box 510 ), the second previous test is performed to determine whether or not the (virtual) subscriber has been authenticated (box 515 ). If the (virtual) subscriber has not been authenticated, the access request is rejected, else, the other test is conducted to determine if the subscriber is a Master SP's subscriber or not (box 520 ). If the subscriber is not a Master SP's subscriber, the original access request is transmitted to Client RADIUS server 430 for subscriber authentication purposes (box 540 ). Upon reception of an authentication acknowledgment from the Client RADIUS server (box 545 ), a test is performed to determine whether or not the subscriber is authenticated (box 550 ). If the subscriber is not authenticated, the access request is rejected. In such case, the virtual subscriber identifier and password are replaced by the real ones before the reject access message is transmitted to the NAS. Else, if the subscriber is authenticated, the connection is established and accounting, e.g., connection duration and number of connections established for corresponding Client SP, may start (box 525 ).
As mentioned above, determining if a subscriber is a Master SP' subscriber or a Client SP's subscriber may be based on subscriber's realm or any equivalent information.
FIGS. 6 to 9 illustrates timing analysis examples of connection process based on the algorithm described by reference to FIG. 5 .
FIG. 6 depicts a first connection example concerning a Master SP's subscriber when connection is accounted for billing the subscriber. When receiving the access request from the subscriber, the NAS transmits the access request with the subscriber identifier (comprising a name and the Master's realm) and the password to the RADIUS proxy. After having determined that access request has been sent by a Master SP's subscriber, the RADIUS proxy transmits this access request comprising subscriber identifier and password to the Master RADIUS server for authenticating the subscriber. If the Master RADIUS server authenticates the subscriber, an access accept message is transmitted back to the RADIUS proxy. Upon reception of the access accept message, the RADIUS proxy forwards this access accept message to the NAS. Then, the NAS sends an accounting start request with the subscriber and session identifiers to the RADIUS proxy. After having determined that accounting request concerns a Master SP's subscriber, the RADIUS proxy transmits this request with the subscriber and session identifiers to the Master RADIUS server. The Master RADIUS server launch an accounting process associated to this subscriber and sends back an accounting start acknowledgment message comprising the subscriber and session identifiers to the RADIUS proxy. This accounting start acknowledgment message comprising the subscriber and session identifiers is then transmitted to the NAS.
FIG. 7 illustrates a second connection example concerning a Client SP's subscriber when connection is rejected by the Master SP. The connection may be rejected by Master SP for reasons explained above, e.g., the subscriber's realm does not correspond to a Client SP or there is no free port for the corresponding Client SP. When receiving the access request from the subscriber, the NAS transmits the access request with the subscriber identifier (comprising a name and a realm) and the password to the RADIUS proxy. The RADIUS proxy copies the access request and modifies it to replace the subscriber identifier and password by virtual subscriber identifier and password associated to the subscriber's realm. If there is no virtual subscriber identifier and password associated with the subscriber's realm, this means that the service provider of this subscriber is not a client of the Master SP. In such case, the access request is rejected by the RADIUS proxy. If there is a virtual subscriber identifier and password associated with the subscriber's realm, which is the case in this example, the modified access request is then transmitted to the Master RADIUS server. The Master RADIUS server checks access capacities allocated to Client SP. If the Client SP is not allowed to create a new connection, the Master RADIUS server sends back an access reject message comprising the virtual subscriber identifier to the RADIUS proxy. The RADIUS proxy transmits this access reject message to the NAS after having replaced the virtual subscriber identifier by the subscriber identifier.
FIG. 8 illustrates a third connection example concerning a Client SP's subscriber when connection is accepted by the Master SP but rejected by the Client SP. When receiving the access request from the subscriber, the NAS transmits the access request with the subscriber identifier (comprising a name and a realm) and the password to the RADIUS proxy. The RADIUS proxy copies the access request and modifies it to replace the subscriber identifier and password by a virtual subscriber identifier and password associated with the subscriber's realm. If there is virtual subscriber identifier and password associated with the subscriber's realm, which is the case in this example, the modified access request is then transmitted to the Master RADIUS server. The Master RADIUS server checks access capacities allocated to Client SP. If the Client SP is allowed to create a new connection, the Master RADIUS server sends back an access accept message, comprising the virtual subscriber identifier, to the RADIUS proxy. The RADIUS proxy then transmits the original access request with the subscriber identifier and password to the Client RADIUS server. If the Client RADIUS server does not authenticate the subscriber, an access reject message comprising the subscriber identifier is transmitted back to the RADIUS proxy. The RADIUS proxy sends this access reject message comprising the subscriber identifier to the NAS.
FIG. 9 illustrates a fourth connection example concerning a Client SP's subscriber when connection is established (accepted by both Master and Client SPs) and accounted for billing the Client SP and the subscriber. When receiving the access request from the subscriber, the NAS transmits the access request with the subscriber identifier (comprising a name and a realm) and the password to the RADIUS proxy. The RADIUS proxy copies the access request and modifies it to replace the subscriber identifier and password by a virtual subscriber identifier and password associated with the subscriber's realm. If there is virtual subscriber identifier and password associated with the subscriber's realm, which is the case in this example, the modified access request is then transmitted to the Master RADIUS server. The Master RADIUS server checks access capacities allocated to Client SP. If the Client SP is allowed to create a new connection, the Master RADIUS server sends back an access accept message, comprising the virtual subscriber identifier, to the RADIUS proxy. The RADIUS proxy then transmits the original access request with the subscriber identifier and password to the Client RADIUS server. If the Client RADIUS server authenticates the subscriber, an access accept message comprising the subscriber identifier is transmitted back to the RADIUS proxy. The RADIUS proxy sends this access accept message comprising the subscriber identifier to the NAS that sends an accounting start message comprising the subscriber and session identifiers to the RADIUS proxy. The RADIUS proxy copies the accounting start message and modifies it to replace the subscriber identifier by a virtual subscriber identifier associated with the subscriber's realm. The modified accounting start message is then transmitted to the Master RADIUS server. The Master RADIUS server launches the accounting process corresponding to the Client SP associated to the subscriber and sends back an accounting start acknowledgment message comprising the virtual subscriber and session identifiers to the RADIUS proxy. The RADIUS proxy then transmits the original accounting start message with the subscriber and session identifiers to the Client RADIUS server. The Client RADIUS server launches the accounting process corresponding to the subscriber and sends back an accounting start acknowledge message comprising the subscriber and session identifiers to the RADIUS proxy. The RADIUS proxy transmits this accounting start acknowledgment message comprising the subscriber and session identifiers to the NAS.
The method and systems of the invention may be used in conjunction with telephone switching equipment having hunting features. Hunting features automatically route calls directed to an initial group of lines, when all the lines of this initial group are busy, to other line(s) in a predetermined group. Thus, when a subscriber of a Client SP initializes a call to a Client SP's POP, using a particular called-number, the call may be automatically transmitted to a Master SP's POP, having another called-number, if this particular called-number is busy. In such case, the subscriber does not need to re-dial another called number and so, does not need to store all the called-numbers of the Master SPs renting access capacities to the subscriber's CSP.
Naturally, in order to satisfy local and specific requirements, a person skilled in the art may apply to the solution described above many modifications and alterations all of which, however, are included within the scope of protection of the invention as defined by the following claims. | For optimizing Internet access resources, a method and systems for sharing network access capacities across Internet service providers is disclosed. According to the method of the invention, a client service provider (CSP) may hire accesses to points of presence belonging to a master service provider (MSP) while maintaining a constant security level and providing connection accounting means. When a CSP's subscriber sends an access request to a MSP, the MSP analyzes the subscriber's realm and checks the capacities allocated to the subscriber's CSP. If connection is allowed, the MSP sends an authentication request to the CSP. If the subscriber is authenticated, the MSP launches an accounting process based on the subscriber's realm while the CSP may launch an accounting process associated with the subscriber identifier. Thus, the MSP does not need to maintain a database comprising information relative to the CSP's subscribers. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a digital signal processor (DSP), and more specifically to a memory organization particularly well adapted to a DSP.
2. Discussion of the Related Art
FIG. 1 schematically and partially shows a conventional DSP architecture. The DSP includes four processing units operating in parallel. Two of these units are memory access units 10 . An arithmetic unit 12 and a branch management unit 14 are further provided. Each of memory access units 10 is associated with an independent memory bus X or Y. A program memory 16 contains compound instructions INST, each compound instruction being actually formed of four simple instructions (INST 1 -INST 4 ) provided at the same time to the respective units 10 , 12 , and 14 . Of course, the four units are often not used at the same time. Then, the compound instruction provided by memory 16 includes NOPs corresponding to the unused units.
A DSP of the type of FIG. 1 is optimized to perform vector operations of the type x[i] OP y[j], where i and j vary, generally in a loop, and where OP designates any operation to be performed by arithmetic unit 12 . Indeed, operands x[i] and y[i] can be fetched together via, respectively, bus X and bus Y and processed in the same cycle by arithmetic unit 12 .
For this type of operation, values x[i] and values y[i] can be respectively stored in two independent memories respectively connected to buses X and Y.
However, a DSP may also need to perform operations of the type z[i] OP z[j], the values of z being all stored in a same memory. In this case, a value z, according to the unit 10 which receives the corresponding read instruction, may be fetched at one time by bus X, at another time by bus Y, or even by both buses at the same time. Thus, access should be possible to a same value z over both buses X and Y.
Theoretically, a dual port memory connected to buses X and Y may be used for this purpose. However, dual port memories are particularly costly in terms of surface.
FIG. 2 illustrates a memory organization which is preferred given the fact that the number of values submitted to operations of the type z[i] OP z[j] is relatively low. This organization includes a dual port memory 18 , the size of which is sufficient to contain “z”-type values, that is, the values which have to be accessible over both buses X and Y. Two single port memories 20 and 22 are respectively associated to “x”-type values and to “y”-type values, the “x”-type values being those which are only accessible over bus X and the “y”-type values being those only accessible over bus Y.
The first address bus of dual port memory 18 and the address bus of single port memory 20 are connected to address bus XA of memory bus X. Similarly, the second address bus of dual port memory 18 and the address bus of single port memory 22 are connected to address bus YA of memory bus Y. The first data bus of memory 18 and the data bus of memory 20 are routed to data bus XD of memory bus X via a multiplexer/demultiplexer 24 . Similarly, the second data bus of memory 18 and the data bus of memory 22 are routed towards data bus YD of memory bus Y by a multiplexer/demultiplexer 26 .
A decoder 28 controls multiplexers/demultiplexers 24 and 26 according to the addresses presented over buses XA and YA. In particular, when the address present on bus XA is in a specific range, decoder 28 controls multiplexer/demultiplexer 24 to route bus XD to memory 18 . Outside the specific range, decoder 28 routes bus XD to memory 20 . The same mechanism is used to control multiplexer/demultiplexer 26 according to the address present on bus YA.
Despite the complexity of multiplexers/demultiplexers 24 and 26 , the surface occupied by this memory organization is generally smaller than that occupied by a single dual port memory gathering memories 18 , 20 , and 22 , this given the fact that the capacity of dual port memory 18 is relatively low.
Multiplexers/demultiplexers 24 and 26 considerably increase the latency times of the read and write operations in the memories.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a memory organization adapted to a digital signal processor enabling access to a same datum by two distinct channels while occupying a particularly small surface and not affecting the latency times of access to the data.
This and other objects are achieved by means of a data processing system comprising a processor provided with two memory access units operating in parallel; two separate memories respectively associated with the two access units; and means for, when the address of a datum to be written into a memory is in a predetermined address range, writing the datum into both memories at the same time at the same address.
According to an embodiment of the present invention, said means comprise two identical write instructions provided at the same time to the two access units.
According to an embodiment of the present invention, said means comprise a first multiplexer connected to copy, in a first access unit a write instruction provided to the second access unit when the write address is in the predetermined range.
According to an embodiment of the present invention, said means comprise a second multiplexer connected to copy into the second access unit a write instruction provided to the first access unit when the write address is in the predetermined range.
The foregoing objects, features and advantages of the present invention will be discussed in detail in the following non-limiting description of specific embodiments in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1, previously described, schematically and partially shows a conventional DSP memory architecture;
FIG. 2 schematically shows a conventional organization adapted to a DSP of the type of FIG. 1;
FIG. 3 schematically shows a memory organization according to the present invention;
FIG. 4 illustrates a solution enabling to use the memory organization of FIG. 3, in a specific case where it is not desired to modify the program of a conventional DSP; and
FIG. 5 illustrates an alternative to the solution of FIG. 4 .
DETAILED DESCRIPTION
In FIG. 3, a memory organization for a DSP of the type in FIG. 2 comprises two single port memories 30 and 32 only. Memories 30 and 32 are respectively connected to buses X and Y of the DSP of FIG. 1 . Memory 30 comprises an area X for storing “x”-type values, while memory 32 comprises an area Y for storing “y”-type values. The two areas correspond to memories 20 and 22 of the conventional organization of FIG. 2 . It should be reminded that the “x” or “y”-type values are those to which access is always had over the same bus X or Y.
According to the present invention, each of memories 30 and 32 is increased by a respective area Z of same size for containing the “z”-type values, that is, the values which must be accessible either over bus X, or over bus Y. Areas Z of memories 30 and 32 are exact copies of each other and are accessible by a same address range, for example, the addresses used to access to memory 18 of FIG. 2 . In other words, if access is had over bus X to a value in area Z of memory 30 , access can be had to this same value at the same address in memory 32 over bus Y.
Of course, for such a memory organization to properly operate, it is necessary to ensure that each value written into area Z of memory 30 is also written at the same address in memory 32 .
In a conventional memory organization of the type in FIG. 2, to write a value z into memory 18 , it is enough to provide a write instruction to any of the access units 10 of the DSP of FIG. 1 . By so operating with a memory organization of the type in FIG. 3, value z is written into a single one of memories 30 and 32 , which is not desirable.
In order to avoid this, an advantageous solution comprises modifying the instructions of the DSP program to always provide to both access units 10 a same instruction of writing of a “z”-type value. This solution requires no hardware modification of the DSP or of the memory organization.
The surface occupied by the two redundant areas Z is comparable to the surface occupied by dual port memory 18 of FIG. 2 . However, multiplexers/demultiplexers 24 and 26 and decoder 28 are omitted, which enables a significant surface saving and a decrease of the latency time of access to memories 30 and 32 .
FIG. 4 illustrates a solution to write a “z”-type value into both memories 30 and 32 without modifying the DSP program. The instruction input of second memory access unit 10 is preceded by a multiplexer 34 that selects the instruction INST 2 provided to this unit, or the instruction INST 1 provided to the first unit 10 . The position of multiplexer 34 is determined by a decoder 36 according to the address carried in the write mode by instruction INST 1 . If this address corresponds to a value z, multiplexer 34 is positioned to select instruction INST 1 . Otherwise, it is positioned to select instruction INST 2 .
This solution of course requires a modification of the DSP of FIG. 1 . The surface occupied by multiplexer 34 and decoder 36 is, however, relatively low. Further, this solution assumes that the write instructions of values z always arrive over bus INST 1 .
FIG. 5 illustrates an alternative to the solution of FIG. 4, by means of which the programmer no longer has to take account of the position of a write instruction for a “z”-type value. An additional multiplexer 38 , also controlled by decoder 36 , precedes the instruction input of the first memory access unit 10 to select one or the other of the two instructions INST 1 and INST 2 . When one or the other of instructions INST 1 and INST 2 is a write instruction for a value z, decoder 36 detects it and positions multiplexers 34 and 38 to duplicate this instruction on both memory access units 10 .
A problem arises when a write instruction for a “z”-type value and another memory access instruction arrive at the same time. It is not possible to have them executed at the same time by both units 10 . The DSP programmer or the compiler could make sure that both accesses are assigned to distinct cycles.
The embodiment of FIG. 5, however, frees the programmer or the compiler from this constraint. For this purpose, decoder 36 is provided to detect the presence over buses INST 1 and INST 2 of two simultaneous memory accesses, one of which is a writing of a value z. Decoder 36 then activates a signal ST indicating a latency of one cycle, and performs two successive positionings of multiplexers 34 and 38 . In the first position, for example, the multiplexers transmit, to units 10 , two copies of the write instruction of value z. In the next position, the multiplexers transmit the other instruction of access to the corresponding unit 10 . Preferably, the other unit 10 then receives a null statement (NOP), but this is difficult to implement without providing additional circuits. Actually, this other unit can receive again the write instruction of value z, which causes the writing twice in a row of the same value at the same memory location, that is, the state of the memory remains unchanged.
Of course, the present invention is likely to have various alterations, modifications, and improvements which will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and the scope of the present invention. Accordingly, the foregoing description is by way of example only and is not intended to be limiting. The present invention is limited only as defined in the following claims and the equivalents thereto. | The present invention relates to a data processing system comprising a processor provided with two memory access units operating in parallel; two separate memories respectively associated with the two access units; and circuitry for, when the address of a datum to be written into a memory is in a predetermined address range, writing the datum into both memories at the same time at the same address. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to computer architectures and, more particularly, to a method and an apparatus for queuing requests from one or more sources to two or more destinations.
2. Description of Related Art
Queues are generally used in computer architectures to provide a buffer of input and/or output data. Devices, also referred to as destinations, such as memory, disk drives, controllers, and the like, typically have a queue that comprises requests for data and/or instructions. A requester, such as a Central Processing Unit (CPU), ports of a CPU, Algorithm Logic Unit (ALU), and the like, submits requests for data and/or instructions. The requests are temporarily stored in a queue, and as the device becomes available, a request is taken from the queue, usually on a First-In-First-Out (FIFO) basis, or some other priority scheme, and submitted to the destination, i.e., the device.
Generally, each device, or group of devices, has its own queue. Requiring each device to have a separate queue, however, requires additional resources to store and manage the queue.
Therefore, there is a need for a method and a system to efficiently manage the queuing of requests for multiple destinations.
SUMMARY
The present invention provides a method and an apparatus for queuing one or more requests to two or more destinations. The method and apparatus utilizes a data table to temporarily store the requests. An age queue is used to select the oldest element for a particular destination. Upon selection of the oldest element from the age queue, the corresponding request from the data table is issued to the destination.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a schematic diagram of a typical network environment that embodies features of the present invention;
FIG. 2 is a block diagram illustrating one embodiment of the present invention in which a data queue and an age queue is used to queue requests to one or more destinations;
FIG. 3 is a schematic diagram of an element of the age queue that embodies features of the present invention;
FIG. 4 is a data flow diagram illustrating one embodiment of the present invention in which requests are placed in a queue;
FIG. 5 is a data flow diagram illustrating one embodiment of the present invention in which a store request is removed from the queues and submitted to a destination;
FIG. 6 is a data flow diagram illustrating one embodiment of the present invention in which a load request is removed from the queues and submitted to a destination; and
FIG. 7 is a data flow diagram illustrating one embodiment of the present invention in which a free-suspend signal is received.
DETAILED DESCRIPTION
In the following discussion, numerous specific details are set forth to provide a thorough understanding of the present invention. However, it will be obvious to those skilled in the art that the present invention may be practiced without such specific details. In other instances, well-known elements have been illustrated in schematic or block diagram form in order not to obscure the present invention in unnecessary detail. Additionally, for the most part, details concerning physical implementation and the like have been omitted inasmuch as such details are not considered necessary to obtain a complete understanding of the present invention, and are considered to be within the skills of persons of ordinary skill in the relevant art.
It is further noted that, unless indicated otherwise, all functions described herein may be performed in either hardware or software, or some combination thereof. In a preferred embodiment, however, the functions are implemented in hardware in order to provide the most efficient implementation. Alternatively, the functions may be performed by a processor such as a computer or an electronic data processor in accordance with code such as computer program code, software, and/or integrated circuits that are coded to perform such functions, unless indicated otherwise.
Referring to FIG. 1 of the drawings, the reference numeral 100 generally designates a computer architecture embodying features of the present invention. The computer architecture 100 generally comprises one or more requesters 110 , such as CPUs, ALUs, one or more ports of a requestor, and/or the like, configured to request the fetching of instructions and/or data from, and/or the storing of data to, one or more destinations 112 , such as memory, disks, hard drives, CD-ROMS, or the like. One or more queues, such as a load queue 114 and a store queue 116 , are configured to receive and temporarily store the requests. As the devices, i.e., the destinations 112 , become available, the load queue 114 and the store queue 116 provide the next request to be performed, typically in a first-in, first-out (FIFO) basis.
The load queue 114 is preferably configured to accept requests for retrieving or fetching instructions and/or data. The store queue 116 is preferably configured to accept requests for storing data in memory or in some other device. It should be noted that only one of the queues 114 , 116 , or additional queues, such as queues servicing a subset of devices, a group of devices, devices of a particular type, or the like, may be implemented based on the requirements of the application, and, therefore, is to be included within the scope of the present invention. The size of each of the load queue 114 and the store queue 116 is dependent upon the application, the available resources, the speed of the requests being generated, the speed of requests being serviced, and the like. Preferably, the size of each of the load queue 114 and the store queue 116 is less than the combined total of the required size of independent queues, providing additional efficiencies.
The following discusses the present invention in terms of the load queue 114 and the store queue 116 providing request queues for a cacheable destination and a non-cacheable destination. These embodiments are for the purpose of providing an example to better illustrate the features of the present invention, and, therefore, should not be construed as limiting the present invention in any manner. The cacheable and non-cacheable destinations may be any destination, commonly referred to as threads, and/or additional destinations that may exist. The use of the present invention in other configurations is considered obvious to one of ordinary skill in the art upon a reading of the present disclosure.
FIG. 2 schematically depicts a queuing system 200 that may be used by the computer architecture 100 in accordance with one embodiment of the present invention to implement a request queue, such as the load queue 114 , the store queue 116 , or the like. The queuing system 200 generally comprises a data queue 210 and an age queue 212 . The data queue 210 preferably comprises one or more data elements 211 , each data element 211 being one or more requests by a requester 110 for data and/or instructions from one or more destinations 112 . The ordering of the data elements is preferably constant, e.g., a request placed in a data element 211 will always be located in the same relative location. In a preferred embodiment, however, such as a CPU requesting data from cacheable and/or non-cacheable destinations, the data queue 210 is of sufficient size to store requests received until the requester 110 can be notified that the data queue 210 is full.
The age queue 212 is preferably a queue that represents the order the requests stored in the data queue 210 were received, the destination of the request, and an indication of the status of the request. Preferably, the age queue 212 comprises age elements 213 in number substantially equal to the number of data elements 211 in the data queue 210 . Furthermore, the age queue 212 is preferably implemented as essentially a First-In, First-Out (FIFO) queue, i.e, ordered based on the age of the request. Other implementations, such as a linked list or the like, may be utilized as long as the relative age is determinable. The preferred contents of the age element 213 are discussed below with reference to FIG. 3 .
A queue select logic component 214 is configured to receive requests and to place the requests in the data queue 210 and the age queue 212 . The process performed by the queue select logic is described in further detail below with reference to FIG. 4 .
An arbiter 216 is configured to select for each destination, or thread, the oldest age element 213 and to control one or more multiplexers (MUX) 220 . Preferably, there is one multiplex 220 for each destination 112 . Each multiplex 220 is preferably configured to have access to all data elements 211 , and to select the data element 211 to be latched to the destination 112 as specified by the arbiter 216 . Furthermore, the arbiter 216 is configured to also provide a state machine 218 with the oldest age element 213 . The state machine 218 is configured to provide control information to the destination 112 and to maintain the age queue 212 as described below with reference to FIGS. 3-7 .
FIG. 3 graphically illustrates the preferred contents of the age elements 213 of FIG. 2 . Specifically, the age element 213 preferably comprises a valid bit 310 , tag bits 312 , one or more bits indicating the destination such as the valid cacheable request bit 314 and the valid non-cacheable request bit 316 , and a retry pending bit 318 . The valid bit 310 indicates whether the request has been serviced, the tag bits indicates the location of the data element 211 corresponding a particular age element 213 , the cacheable request bit 314 and the non-cacheable request bit 316 indicate the destination of the request, and the retry pending bit 318 indicates whether the request has been tried and rejected by the destination 112 . The preferred operation and functioning of these bits will be described below with reference to FIGS. 4-7 .
FIG. 4 is a flow chart depicting steps that may be performed by the queue select logic 214 in the course of one embodiment of the present invention to place requests for data and/or instructions into queue to be processed by one or more destinations 112 . Accordingly, in step 410 the queue select logic receives a request for data and/or instructions. Upon receipt of the request, processing proceeds to step 412 , wherein a determination is made whether there is an available data element 211 . If a determination is made that a data element 211 is not available, then processing proceeds to step 414 , wherein the request is refused. If, however, in step 412 , a determination is made that a data element 211 is available, then processing proceeds to step 416 , wherein the data queue 210 and the age queue 212 is updated to reflect the new request. Preferably, the request is stored in the available data element 211 . The valid bit 310 of the age queue 212 is set to indicate a new request to be executed. The tag bits 312 of the age queue 212 are set to identify the data element 211 of the data queue 210 that corresponds to the data element in which the request was stored.
Processing then proceeds to steps 418 - 434 , wherein determinations are made as to which thread and/or destination the request belongs. In the present example, the threads and/or destinations refer to a cacheable destination and a non-cacheable destination. Accordingly, in step 418 , a determination is made whether the request is both a cacheable request and a non-cacheable request, i.e., the request is to be issued to both a cacheable destination and a non-cacheable destination, such as synchronization operation and the like. If a determination is made that the request is both a cacheable and a non-cacheable request, then processing proceeds to step 420 , wherein the cacheable request bit 314 and the non-cacheable request bit 316 are set.
If, in step 418 , a determination is made that the request is not both a cacheable request and a non-cacheable request, then processing proceeds to step 422 , wherein a determination is made whether the request is only a cacheable request, such as a load operation to cacheable memory, a store operation to cacheable memory, or the like. If a determination is made that the request is only a cacheable request, then processing proceeds to step 424 , wherein the cacheable request bit is set.
If, in step 422 , a determination is made that the request is not only a cacheable request, then processing proceeds to step 426 , wherein a determination is made whether the request is only a non-cacheable request, such as a load operation to non-cacheable memory/device, a store operation to non-cacheable memory/device, or the like. If a determination is made that the request is only a non-cacheable request, then processing proceeds to step 428 , wherein the non-cacheable request bit 316 is set.
If, in step 426 , a determination is made that the request is not only a non-cacheable request, then processing proceeds to step 430 , wherein a determination is made whether the request contains an indication of the destination. Preferably, the request contains one or more bits, such as the cache inhibited bit (i-bit) contained in the PowerPC architecture defined by IBM, Corp., Apple Computers, Inc., and Motorola, Inc., that indicate the type of destination of the request. In the present example, a single bit may be used to indicate cacheable (the i-bit is not set) or non-cacheable (the i-bit is set). If a determination is made that the request is cacheable, then processing proceeds to step 432 , wherein the cacheable request bit 314 is set. If, in step 430 a determination is made that the request is not a cacheable request, i.e., it is a non-cacheable request, then processing proceeds to step 434 , wherein the non-cacheable request bit 316 is set.
FIG. 5 is a flow chart depicting steps that may be performed by the computer architecture 100 for each type of destination in accordance with one embodiment of the present invention that selects the oldest element in the age queue 212 ( FIG. 2 ) for a store operation. Processing begins in step 510 , wherein a determination is made whether the destination is prepared to accept a request. The status of the destination may be determined by any suitable means, such as maintaining a count of operations, handshaking, and/or the like.
If, in step 510 , a determination is made that the destination is not prepared to accept a request, then processing waits, i.e., no store requests are sent to the destination, until the destination indicates that the destination is prepared to accept a store request. If, however, in step 510 , a determination is made that the destination is prepared to accept a store request, then processing proceeds to step 512 , wherein the oldest store request is selected from the age queue 212 . In step 514 , the arbiter 216 extracts the tag bits 312 and sends the tag bits 312 to the mux 220 , which latches the data element 211 identified by the tag bits 312 through to the destination. In step 516 , the destination is notified, preferably by the state machine, that a new request is available. In step 518 , the valid bit 310 and the cacheable/non-cacheable request bits 314 , 316 are reset and the corresponding data element 211 is reallocated.
FIG. 6 is a flow chart depicting steps that may be performed by the computer architecture 100 for each type of destination in accordance with one embodiment of the present invention that selects the oldest element in the age queue 212 ( FIG. 2 ) that is not suspended, i.e., the retry pending bit 318 is not set, for a load operation. Processing begins in step 610 , wherein the oldest entry in the age queue 212 is selected.
In step 612 , the arbiter 216 extracts the tag bits 312 to send to the mux 220 , which latches the data element 211 identified by the tag bits 312 through to the destination. In step 614 , the destination is notified, preferably by the state machine 218 , that a new request is available. In step 616 , a determination is made whether the request has been accepted and executed by the destination. If a determination is made that the request has been accepted and executed by the destination, then processing proceeds to step 618 , wherein the valid bit 310 is reset and the data element 211 is reallocated.
If, in step 616 , a determination is made that the request has not been executed, then processing proceeds to step 620 , wherein the retry pending bit 318 is set to indicate that the request has yet to be executed. In some circumstances, such as when the destination is busy, there is arbitration failure, the destination is accepting only specific operations and/or addresses, or the like, the destination will not execute the request. In these situations, it is preferable that the request be suspended and retried at a later time. Preferably, the request remains suspended until the retry pending bit 318 is reset, as described below with reference to FIG. 7 .
FIG. 7 is a flow chart depicting steps that may be performed by the computer architecture 100 for each type of destination in accordance with one embodiment of the present invention that resets the retry pending bit 318 of a suspended load operation as described above with reference to step 620 (FIG. 6 ). More particularly, if a load operation was not performed and the retry pending bit 318 is set as determined above in step 620 , the request is suspended until the retry pending bit 318 is reset as described below with reference to steps 710 - 716 .
Accordingly, processing begins in step 710 , wherein a command or signal, such as a free-suspend signal, is received from the destination. Upon receipt of the free-suspend signal, processing proceeds to step 712 , wherein a determination is made from which destination the free-suspend signal was received. Preferably, the free-suspend signal comprises one or more bits that indicate the destination, i.e., the source of the free-suspend signal. In the instant case, a single bit may be used to indicate the destination as either the cacheable destination or the non-cacheable destination.
If, in step 712 , a determination is made that the free-suspend signal was received from the cacheable destination, then processing proceeds to step 714 , wherein the retry pending bit 318 is reset for all valid cacheable requests. If, however, in step 712 , a determination is made that the free-suspend signal was received from the non-cacheable destination, then processing proceeds to step 716 , wherein the retry pending bit 318 is reset for all valid non-cacheable requests. Thereafter, the requests may be processed as described above with reference to FIGS. 5 and 6 .
Having thus described the present invention by reference to certain of its preferred embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered obvious and desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention. | A method and an apparatus for sharing a request queue between two or more destinations. The method and apparatus utilizes a common data table and a common age queue. The age queue is used to select the oldest request. The corresponding request from the common data table is then extracted and sent to the appropriate destination. | 6 |
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