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CROSS-REFERENCE TO RELATED APPLICATIONS
Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
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INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
Not Applicable
FIELD OF THE INVENTION
The invention relates to pressurised steam boilers and their control, to a method and apparatus for detecting the level of water in a steam boiler and to a method and apparatus for assessing the mass flow of steam from a steam boiler.
BACKGROUND OF THE INVENTION
In a known arrangement of a pressurised steam boiler, water is fed into the boiler at a controlled rate and is heated in the boiler to convert the water to steam. The heat required to convert the water to steam is provided by a burner whose hot products of combustion are passed through ducts in the boiler and then exhausted. The steam boiler is controlled by a boiler control system, which receives information from sensors indicating inter alia the level of water in the boiler and the presence of steam in the boiler, and which controls the flow rate of water into the boiler as well as sending a control signal to a burner control system that controls the burner. The burner control system controls inter alia the flow of fuel and gas to the burner head in dependence upon a demand signal received from the boiler.
Pressurised steam boilers are potentially very hazardous because of the very high pressure that is maintained in the boiler and it is therefore essential for such boilers to have control systems that are extremely safe. One factor that is taken into account to ensure the safety of a system is the importance of maintaining the water level in the boiler within predetermined limits. The internationally recognised safety regime concerning adequate water level in pressurised steam boilers requires sensing arrangements to detect a first low water level (“first low”) below the normal operating range of the boiler and also to detect a second low water level that is even lower than the first low water level. When the first low water level is detected, the boiler control system sends a signal to the burner control system causing the burner to be switched off. Provided the water level then rises back above the first low water level the boiler control system sends a further signal to the burner control system allowing the burner to restart. If, however, the water level continues to fall and reaches the second low water level, the boiler control system sends a further signal to the burner control system preventing it from restarting without manual intervention. The requirement for manual intervention is inconvenient, but is regarded as a necessary safety requirement.
The false triggering of either the first low or second low is costly. The effect of a false triggering at the first low is to turn off the burner; at best that may simply lead to less efficiency because the burner is switched completely off rather than simply being turned down to a lower firing rate; in a worst case, however, as will be explained below, the false triggering may lead to the burner being switched off at a time when the demand for heat in the boiler is especially high. False triggering at the second low is more damaging because it is likely to last longer given that the burner can be restarted only after manual intervention.
False triggering can occur without any fault in the equipment. In particular, it is not unusual for there to be a sudden demand for steam from a steam boiler; in that case there may be a significant drop in pressure within the boiler which can cause the water level in the boiler to rise (because of the small bubbles of compressed gas trapped within the water in the boiler). The reduction in pressure rightly leads to a signal passing from the boiler control system to the burner control system to increase the firing rate of the burner, while the increase in water level in the boiler causes the usual water flow into the boiler to be reduced or stopped. As the system then recovers and the pressure in the boiler rises, the water level in the boiler falls quickly and may well fall below the “first low” leading to the burner being turned off at a time when it should be operating, probably at full capacity. It is even possible that the fall in water level will reach the “second low” so that the burner remains off until an operator resets the system.
Safety considerations also have an impact on the techniques that are employed to measure the level of water in the boiler. Because of the importance of detecting the “first low” and the “second low”, separate probes are used to detect each of the levels; whilst one capacitative probe may sometimes be provided to sense water levels within the normal operating range, respective conductive probes, which sense whether or not they are in the water, but give no further indication of water level, are provided to detect the “first low” and the “second low”. Often other conductive probes are set at other levels so that those other levels can be detected in a similar way. Thus a large number of separate probes are provided. A capacitative probe is not regarded as sufficiently reliable for detecting the “first low” and the “second low” water levels. Particular concerns are that the signals from such probes are affected by temperature variations and may also be affected by stray electromagnetic radiation generated by devices in the vicinity of the probes.
A further problem when attempting to measure water levels in steam boilers is that whenever the water is boiling a certain amount of turbulence is present, making it difficult to measure the water level accurately.
Operators of pressurised steam boilers frequently purchase steam flow meters to measure the steam flows in the steam exit lines from each of the boilers. A frequent reason for installing such meters is for auditing purposes, to enable the amount of steam exported from the boiler to be compared to the amount of fuel used by the boiler. Such meters are, however, expensive.
BRIEF SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved method and apparatus for controlling the operation of a steam boiler.
It is a further object of the invention to provide a method and apparatus for controlling the operation of a steam boiler in which the likelihood of a burner being shut down unnecessarily is reduced.
It is a further object of the invention to provide an improved method and apparatus for detecting the level of water in a pressurised steam boiler, and especially to provide a method and apparatus in which the number of probes that are required is reduced.
It is a still further object of the invention to provide a method and apparatus for assessing the mass flow of steam from a pressurised steam boiler without resorting to a steam flow meter.
It is a still further object of the invention to provide a method and apparatus for monitoring turbulence in a pressurised steam boiler.
According to the invention there is provided a method of controlling the operation of a steam boiler heated by a burner, the method including the following steps:
a) monitoring the level of water in the boiler, b) monitoring the pressure of steam in the boiler, c) monitoring the firing rate of the burner, and d) controlling the flow rate of water into the boiler having regard to the signals resulting from a) and b) and, at least for some signal conditions, also having regard to signals resulting from c).
By using the firing rate of the burner as one of the control inputs for determining the flow rate of water into the boiler and in that respect combining the burner control system and the boiler control system, it becomes possible to effect a more appropriate control of the water, reduce the number of times that the water level in the boiler falls below a first low water level at which the burner is switched off and thereby improve the efficiency of the boiler.
Whilst it is within the scope of the invention for the control of the flow rate of water into the boiler always to take account of signals resulting from monitoring the firing rate of the burner, it may be that the signals resulting from monitoring the firing rate of the burner are taken into account in a limited set of circumstances only. It is for example preferred that when
i) the monitoring of the level of water in the boiler shows a rate of increase above a predetermined level, ii) the monitoring of the pressure of steam in the boiler shows a reduction in pressure at a rate above a predetermined level, and iii) the monitoring of the firing rate of the burner shows that the firing rate is increasing at a rate above a predetermined level, the controlling of the flow rate of water into the boiler is such that it does not necessarily reduce the rate of flow into the boiler.
Preferably, said controlling of the flow rate of water into the boiler is such that it does not reduce the rate of flow into the boiler, unless the level of water in the boiler is above an upper normal working limit. In a case where there is a sudden demand for steam so that the steam pressure drops quickly and the water level in the boiler increases rapidly, the flow rate of water into the boiler is controlled in dependence upon what is concurrently happening to the firing rate of the burner: if the firing rate of the burner is increasing at a rate above a predetermined level, then that is an indication that the drop in steam pressure is a result of increased demand and that the increase in boiler water level is misleading, and the rate of flow of water into the boiler is not reduced. Since water continues to flow into the boiler the likelihood of the water level dropping below the first or second low water levels is significantly reduced.
An example of a situation where the monitoring of the firing rate would still lead to a reduction in the rate of flow of water into the boiler is given below: when
i) the monitoring of the level of water in the boiler shows an increase in level but at a rate of increase below a predetermined level. ii) the monitoring of the pressure in the boiler shows an increase in pressure but at a rate of increase below a predetermined level, and iii) the monitoring of the firing rate of the burner shows that the firing rate is reducing the controlling of the flow rate of water into the boiler is such that it does reduce the rate of flow into the boiler.
Preferably, input and output signals relating to all the monitoring and controlling steps are passed into or transmitted from a common control unit that also controls the operation of the burner. The integration of the boiler control unit and burner control unit into a single control unit simplifies, improves and makes cheaper the control of the burner and boiler.
Where reference is made above to a rate of increase above a predetermined level, it is within the scope of the invention for the rate of increase to be at any level above zero. It is preferred, however, that the predetermined level corresponds to what is to be regarded as a normal rate of increase during ordinary operation of the burner and boiler. Appropriate predetermined levels may be determined by a commissioning engineer during commissioning of the system and a rate of increase may be obtained by measuring the increase in values over a time period of the order of 20 seconds.
Where reference is made to monitoring a variable, it should be understood that the variable itself may not be directly sensed but rather one or more other variables, from which the variable being monitored can be calculated, may be sensed.
For example, the firing rate of the burner need not be directly sensed and the pressure of the water in the boiler may be sensed to indicate the pressure of the steam.
In an especially preferred method, the step of monitoring the level of water in the boiler includes the steps of providing a pair of capacitance probe assemblies mounted in the boiler with each of the probes extending through a range of water levels, the probes being arranged such that the capacitance of each probe varies according to the level of the water, and of measuring the capacitance of each probe, comparing the capacitances to one another to check that they match and using the measurement of the capacitance as an indication of the water level. By providing a capacitance probe assembly to measure the water level in the boiler it becomes possible to measure a wide range of levels and, if desired, all the intermediate levels without a large number of probes. Furthermore, by providing a pair of probes that measure the same levels, safety can be considerably improved. Of course, more than two probes can be employed, if desired.
The method may further include the step of shutting down the burner in the event that a discrepancy between the capacitances of the probes exceeds a given level.
The range of water levels through which the probes extend preferably includes a first low water level below the normal working range. Thus the probes are preferably used to detect the “first low”. Furthermore, the range of water levels through which the probes extend preferably includes a second low water level below the first low water level. Thus the probes are preferably also used to detect the “second low”. Conventional capacitative probes have not been regarded as satisfactory for detecting the “first low” and “second low” because of the importance, from a safety point of view, of that detection. We have found, however, that by using a pair of probes to make the same measurements it is possible to provide a very safe detecting arrangement.
It is still further preferred that the range of water levels through which the probes extend include all other water levels that are to be detected. In that case there is no need to provide any other water level detectors apart from the probes. The further water levels detected by the probes may be the limits of the normal working range of water level and/or a high water level above the normal working range and/or other levels which may be required by particular laws or codes of practice in a given country.
Each of the capacitance probes preferably projects downwardly from an upper region of the boiler housing. Each probe preferably comprises an elongate core of electrically conducting material surrounded by a sleeve of electrically insulating material.
Preferably the pair of capacitance probe assemblies are substantially identical.
Each capacitance probe assembly preferably includes in addition a reference capacitance whose capacitance value is sensed alternately with the probe capacitance value. By providing such a reference capacitance value in each probe assembly, it is possible to detect any distortion of the sensed value of capacitance that might arise. A cause of such a discrepancy would be a change in the temperature of the probe assembly. That would change the sensed values of both the reference capacitance and the probe capacitance and, since the reference capacitance is known, enables a correction to be made to the sensed value of the probe capacitance. Furthermore, if desired, a temperature monitoring device can be provided in the probe assembly and can, via for example a look-up table, calculate a correction to be made to the sensed value of the probe capacitance; a check can then be made that the two different methods of correcting the sensed value of the probe capacitance do not differ by more than a given amount and, if they do, the burner can be shut down. Another cause of such a discrepancy might arise, for example, from electromagnetic radiation. We have found that by using two capacitance probe assemblies as described it is possible to measure water level to an accuracy of plus or minus 2 mm in calm conditions.
The measurement of the capacitance of one probe may alternate with the measurement of the capacitance of the other probe, or the measurements may be made simultaneously.
In an especially preferred method of the invention, the level of water in the boiler is monitored by a water level monitoring device capable of monitoring a multiplicity of water levels extending over a range, the water level is monitored at a plurality of different times and the monitoring results at the different times compared to assess whether or not the water is turbulent.
An ability to assess whether or not the water is turbulent enables a further safety factor to be introduced: for example, when other controls indicate that the boiler is producing steam, then the water in the boiler should be turbulent and an assessment of lack of turbulence may be regarded as an indication of a fault. It should be understood that in the context of this specification the term “turbulence” is applied to any disruption to a level water surface, such as may be caused by a wave, by a bubble of steam reaching the surface or by foam on the surface.
Preferably the water level monitoring device is capable of monitoring the water level continuously over its range.
The times of monitoring are preferable separated from one another by less than one half of one second, and more preferably by less than one quarter of one second. In an embodiment of the invention described below the rate of monitoring is ten times per second. The rate is preferably substantially shorter than the period of a wave. Preferably a plurality of monitoring results spanning a time period containing more than one peak of water level are combined together to provide a measure of the water level; that enables a reasonably accurate measurement of water level to be obtained, even when the water is turbulent. Preferably the combining together of the results is weighted in favour of results indicating a relatively low water level; we have found that in turbulent water in a boiler, the peaks of water level contain very little water; thus in an embodiment of the invention described below, the highest and lowest water level results contained in the time period are noted and an inference of the actual level obtained by giving nine times more weight to the lowest level result than to the highest level result.
Preferably the assessment of whether or not the water is turbulent is used as an input to a control unit for controlling the burner.
Preferably a pair of water level monitoring devices are provided. Preferably the water level monitoring devices are capacitance probe assemblies. Preferably, an average of signals from one device is combined with an average of signals from the other device to provide an assessment of the water level.
An especially preferred method of the invention further includes the step of assessing in a control unit the mass flow of steam from the boiler by processing of input signals including ones enabling assessments to be made of:
a) the heat generated by combustion in the burner b) the temperature and pressure of the steam generated by the boiler c) the heat dissipated other than in the steam.
It should be understood that a designer is able to make some selections as to how accurate the assessments of a) to c) above are to be and therefore how many variables are to be measured and how accurately they are to be measured. For example, in order to assess the heat dissipated other than in steam an operator might merely measure the temperature of the combustion products and assume a certain further dissipation of heat by other means such as conduction, convection and radiation from the boiler housing.
By making an assessment of the mass flow of steam from measurements of other variables, the need for an expensive steam flow meter is avoided. Although it may appear that the measurement of several other variables in order to assess the steam flow is unnecessarily expensive and complicated, that need not be so because the other variables may be mainly or entirely ones that are being measured anyway for the purpose of controlling the operation of the pressurised steam boiler and burner.
Variables measured to assess the heat generated by combustion in the burner may include the rate of feeding of fuel to the burner, and/or the composition of the combustion products.
Variables measured to assess the heat dissipated other than in the steam may include the temperature of the combustion products and/or the rate of feeding fuel to the burner.
In GB 2169726A, the description of which is incorporated herein by reference, a fuel burner control system is described which includes flue gas sampling and analysing apparatus and which also includes a burner controller which is the subject of GB 2138610A, the description of which is also incorporated herein by reference. That control system already receives inputs relating to the rate of feeding fuel to the burner, the composition of the exhaust gases and the temperature of the exhaust gases. Furthermore it is common for a pressurised steam boiler control system to include sensors for measuring the temperature and pressure of the steam generated by the boiler. Thus it can be seen that all the variables required for the assessment of the mass flow of steam from the boiler may already be available without any extra sensors being required. If desired, however, one or more extra sensors may be provided. For example, a sensor for measuring the temperature of the water being fed into the boiler may be provided.
The assessment of the mass flow of steam from the boiler may be used only as a measure of the flow at a moment in time, or it may also or alternatively be used to provide an assessment of the aggregate amount of steam generated over a certain extended period of time. In the latter case, it may be necessary to allow for other losses within the system, when making the assessment, for example it may be appropriate to assume that a certain percentage of heat is lost during blow down of a boiler. For example an overall loss of 6 percent might be allowed for.
The present invention further provides a method of monitoring the level of water in a pressurised steam boiler, the method including the steps of providing a pair of capacitance probe assemblies mounted in the boiler with each of the probes extending through a range of water levels, the probes being arranged such that the capacitance of each probe varies according to the level of the water, and of measuring the capacitance of each probe, comparing the capacitances to one another to check that they match and using the measurement of the capacitance as an indication of the water level.
The present invention yet further provides a method of assessing in a control unit the mass flow of steam from a pressurised steam boiler by processing input signals including ones enabling assessments to be made of:
a) the heat generated by combustion in the burner b) the temperature and pressure of the steam generated by the boiler c) the heat dissipated other than in the steam.
Although the invention has been defined above with reference to a method, it will be understood that it may also be embodied in an apparatus comprising a pressurised steam boiler. Thus the present invention still further provides a pressurised steam boiler including
a boiler housing for containing water in the boiler, a burner for heating water in the boiler and converting the water into steam, a water level detector for monitoring the level of water in the boiler, a pressure detector for detecting the pressure of steam in the boiler, a firing rate detector for detecting the firing rate of the burner, and a control unit which receives input signals from the water level detector, the pressure detector and the firing rate detector and is operative to control the flow rate of water into the boiler in dependence upon said input signals.
The present invention still further provides a pressurised steam boiler including:
a boiler housing for containing water in the boiler, and a water level detector for monitoring the level of water in the boiler, the water level detector comprising a pair of capacitance probe assemblies mounted in the boiler housing with each of the probes extending through a range of water levels, the probes being arranged such that the capacitance of each probe varies according to the level of water, and a control and processing system for measuring the capacitance of each probe, comparing the capacitances and providing an output signal indicative of water level based on the capacitance measurements.
The present invention still further provides a pressurised steam boiler including:
a boiler housing for containing water in the boiler, a burner for heating water in the boiler and converting the water into steam, a pressure detector for detecting the pressure of steam in the boiler, a temperature detector for detecting the temperature of steam in the boiler, a fuel flow detector for measuring the flow rate of fuel into the burner, a further temperature detector for detecting the temperature of the exhaust gases, a control unit for receiving and processing input signals from all of said detectors and for assessing indirectly the mass flow of steam from the boiler.
The present invention still further provides a pressurised steam boiler including:
a boiler housing for containing water in the boiler. a water level monitoring device capable of monitoring a multiplicity of water levels extending over a range, and a control unit for storing results of monitoring the water level at a plurality of different times and for comparing the results to assess whether or not the water is turbulent.
It will be appreciated that features described above with respect to methods of controlling the operation of a pressurised steam boiler, methods of monitoring the level of water in a pressurised steam boiler, methods of assessing the mass flow of steam from a pressurised steam boiler and methods of monitoring turbulence in a pressurised steam boiler may be incorporated, wherever that is possible, in any of the pressurised steam boilers as described above. Furthermore, a feature described with respect to one of the methods described above may also be incorporated, wherever that is possible, in any of the other methods described above.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
By way of example, an embodiment of the invention will now be described with reference to the accompanying drawings, of which:
FIG. 1 is a schematic drawing of a burner and a pressurised steam boiler and of a control unit for controlling the burner and steam boiler,
FIG. 2 is a schematic drawing of the pressurised steam boiler of FIG. 1 ,
FIG. 3 is a sectional view of one of a pair of capacitance probe assemblies employed in the pressurised steam boiler shown in FIG. 2 , and
FIG. 4 is a block circuit diagram of the signal control and processing arrangement provided in each capacitance probe assembly.
DETAILED DESCRIPTION OF THE INVENTION
Referring first to FIG. 1 , there is shown a burner 20 having a burner head 21 , a combustion chamber 22 and a duct 23 for combustion products which comprise exhaust gases. As will be described below the duct 23 passes through a pressurized steam boiler; thereafter the exhaust gases are vented through a flue.
Air is fed to the burner head 21 from an air inlet 24 , through a centrifugal fan 26 and then through an outlet damper 27 . The burner head 21 is able to operate with either gas or oil as the fuel; gas is fed to the burner head from an inlet 28 via a valve 29 whilst oil is fed to the burner head from an inlet 30 via a valve 31 .
A control unit 1 is provided for controlling the operation of the burner and boiler. The control unit 1 has a display 2 , a proximity sensor 3 for detecting that a person is nearby, and a set of keys 5 enabling an operator to enter instructions to the control unit. The purpose of the proximity sensor is not relevant to the present invention and will not be described further herein; its purpose is described in GB2335736A, the description of which is incorporated herein by reference.
The control unit 1 is connected to various sensing devices and drive devices, as shown in the drawing. More particularly the unit is connected via an exhaust gas analyser 37 to an exhaust gas analysis probe 38 (which includes a temperature sensor), and to a flame detection unit 40 at the burner head. The control unit 1 is also connected via an inverter interface unit 41 and an inverter 42 to the motor of the fan 26 (with interface unit 41 receiving a feed back signal from a tachometer 26 A associated with the fan 26 ), via an air servo motor 44 to the air outlet damper 27 , to an air pressure sensing device 45 provided in the air supply duct downstream of the outlet damper 27 , via fuel servo motors 46 to the fuel valves 29 , 31 and to a further servo motor 47 for adjusting the configuration of the burner head 21 .
The connections described above relate to the control of the burner 20 by the control unit 1 . The control unit 1 is, however, also connected, via an RS485 link 48 to a further controller 49 , which is shown in FIG. 2 and whose functions are described below.
The combustion chamber 22 of the burner 20 is arranged inside a boiler 50 in a conventional manner. In FIG. 1 the boiler 50 is shown schematically in chain dotted outline. Although FIG. 1 suggests that the combustion chamber leads directly to the exhaust duct 23 , it will be understood by those skilled in the art that in practice the gaseous products of combustion follow a serpentine path passing through the boiler 50 a few times before reaching the exhaust duct 23 and being exhausted to atmosphere.
FIG. 2 provides a schematic representation of the boiler and shows a boiler housing 51 which in normal use is filled to approximately the height shown by dotted line LI in FIG. 2 . It will be appreciated that the combustion chamber and ducting for the exhaust gases are not shown in FIG. 2 .
A water pipe 52 feeds water into the bottom of the boiler at a rate determined by settings of a variable speed pump 53 and via a motorized control valve 54 . A temperature detector 59 senses the temperature of the water as it enters the boiler.
A steam outlet pipe 55 takes steam under pressure from the top of the boiler 51 . The pressure of the steam taken from the boiler housing 51 is sensed by a pressure detector 56 while its temperature is sensed by a temperature detector 57 . Mounted in the top of the boiler housing 51 are a pair of capacitance probe assemblies 58 A and 58 B. The capacitance probe assemblies are identical to one another and one is described below with reference to FIGS. 3 and 4 .
The further controller 49 receives input signals from the following (excluding the connection via the RS485 link 48 to the control unit 1 ):
a) each of the capacitance probe assemblies 58 A and 58 B; b) the steam temperature detector 57 ; c) the inlet water temperature detector 59 ; d) the control valve 54 (a feedback signal indicating the degree of opening of the control valve 54 ); and e) the pump 53 (a feedback signal indicating the setting of the pump).
In addition a signal from the pressure detector 56 is passed back along a line 60 (not shown in FIG. 1 ) to the control unit 1 where it provides an input signal representing demand to the control unit.
The further controller 49 provides output signals to the following (excluding the connection via the RS485 link 48 to the control unit 1 ):
i) the control valve 54 (to adjust the degree of opening of the valve); ii) the pump 53 (to adjust the setting of the pump); iii) a warning light and audible alarm 61 A, 61 B, respectively, which are activated when the water level falls to a first low water level below its normal operating range “first low”); iv) a warning light and audible alarm 62 A, 62 B, respectively, which are activated when the water level falls to a second low water level below the first water level (“second low”); and v) a warning light and audible alarm 63 A, 63 B, respectively, which are activated when the water level rises to a high water level above its normal operating range.
It will be understood that the particular warning light and audible alarms that are employed may be varied from one application to another according to what is required.
In FIG. 2 , the dotted line LI indicates the centre of the normal operating range of water level in the boiler. Also shown is a dotted line L 2 marking the “first low”, a dotted line L 3 marking the “second low” and a dotted line L 4 marking the high water level.
Referring now also to FIG. 3 , it can be seen that each capacitance probe assembly 58 A, 58 B includes a main body 70 and an elongate probe 71 which projects downwardly into the interior of the boiler and extends through the high water level (L 4 ), the normal operating level (L 1 ), the “first low” (L 2 ) and the “second low” (L 3 ). Since boilers vary in size the probes 71 are manufactured in various lengths and an appropriate length of probe is chosen for each boiler. For example, the probes may be available in lengths of about 0.5 m, 1.0 m and 1.5 m.
Each probe 71 is formed from a central steel bar 72 surrounded by a sleeve 73 of dielectric material. Also a plug 74 of dielectric material is provided at the free end of the sleeve 73 to seal that end of the probe. Thus, in a manner that is know per se, the probe 71 forms together with the medium surrounding the sleeve 73 a variable capacitance. Since the capacitance is very dependent on whether the medium is water or steam the value of the capacitance is dependent upon how great a length of the probe is surrounded by water rather than steam. Thus, the capacitance of the probe provides an indication of the level of water in the boiler, for all levels between, and including, L 3 and L 4 .
Within the main body 70 of the capacitance probe assembly, there is a secure physical and electrical connection to the probe and a printed circuit board 75 is mounted in an enlarged rear portion 76 of the main body 70 , the board 75 carrying the necessary processing circuitry, which is shown in block diagram form in FIG. 4 .
Referring now also to FIG. 4 , there is shown the probe 71 marked as a varying capacitance, a reference capacitance 77 , a relay 78 for alternately connecting the probe 71 and the reference capacitance in the circuit, an oscillator 79 , a processor 80 which both controls the operation of the relay 78 and together with the oscillator 79 is able to provide a measure of the capacitance being sensed by detecting the frequency of a signal in a circuit incorporating the capacitance, and a driver 81 which transmits a signal from the probe assembly to the further controller 49 . The connection between each probe assembly 58 A, 58 B and the further controller 49 is made via RS485 links.
In a particular example of the invention, the probe capacitance varies from 10 pF to 200 pF, the reference capacitance 77 is 120 pF, the oscillator 79 is a 555 Type Oscillator, the processor 80 is an 80188 processor and the sleeve 73 is 12 mm outside diameter, 6 mm inside diameter and is made of PTFE (polytetra-fluoroethylene). As the probe capacitance varies due to a change in water level the frequency of the output from the probe assembly alters; typically, the frequency output is of the order of 45,000 Hz and a change of 1 mm in water level alters the frequency by 20 Hz.
When connected in the control system shown in FIGS. 1 and 2 , the capacitance of each probe 71 is measured alternately with the reference capacitance 77 of that probe. In the event of a change in temperature, that affects values of both the capacitance of the probe 71 and its reference capacitance 77 , so that the change in value of the reference capacitance can be used to adjust the signal from the probe capacitance to compensate for such a temperature change. Also the controller 49 reads signals from each of the probe assemblies 58 A, 58 B alternately, although, if preferred, simultaneous readings may be obtained. Typically in a steam boiler, the water is somewhat turbulent at least near the surface and that is liable to give rise to some inaccuracy in the measurement made. Thus the controller 49 is arranged to allow for some discrepancy in the signals from the probe assemblies 58 A, 58 B, but apart from that checks both that the signal of the reference capacitance indicates the correct value of capacitance and that each of the probes 71 indicates the same value of capacitance and therefore the same water level. One particular way in which turbulence in the water can be allowed for and indeed even taken advantage of is described later.
The use of the two identical probe assemblies 58 A, 58 B each with its own reference capacitance for checking purposes and with all readings from both probe assemblies being checked against one another, results in an especially safe system.
The normal operation of the burner and boiler will be well understood by those skilled in the art from the description above and will not be described further herein. GB2138610A and GB2169726A both provide further details of the normal operation of the burner. The boiler operates in a conventional manner when the water level is normal and, via the controller 49 , feeds back signals, for example indicating a dropping steam temperature, to the control unit 1 . In the event that the water level in the boiler drops to below the average normal level, then the controller 49 is programmed to adjust the speed of the pump 53 at the water inlet to allow more water into the boiler; similarly, in the event that the water level in the boiler rises gradually a little above the average normal level, then the controller 49 is programmed to close the control valve 54 or reduce the speed of the pump 53 at the water inlet to allow less water into the boiler. In either case, however, the operation of the burner 20 is not affected because the output signals from the control unit 1 are not altered.
If, however, for example, the water level in the boiler falls to the level L 2 shown in FIG. 2 , then the controller 49 reacts in various ways: firstly the warning light 61 A and audible alarm 61 B are actuated; secondly a signal is passed back via the RS485 link 48 to the control unit 1 which then shuts down the burner 20 by turning off the supplies of fuel and air to the burner head 21 ; thirdly, the inlet flow of water into the boiler 5 is increased by adjustment of the control valve 54 and/or the pump 53 .
Provided that the water level then rises back towards the level L 1 , the controller 49 can reverse the measures described in the paragraph immediately above. If for some reason, however, the water level continues to fall, for example because the water inlet is blocked, then when it reaches the level L 3 in FIG. 2 the warning light 62 A and the audible alarm 62 B are activated and a further control signal sent from the controller 49 to the control unit 1 , preventing the burner from being turned back on without manual intervention by an operator.
Similarly, if the water level in the boiler rises to the level L 4 shown in FIG. 2 , then the controller 49 reacts in various ways: firstly the warning light 63 A and the audible alarm 63 B are activated; secondly a signal is passed back via the RS485 link 48 to the control unit 1 which then shuts down the burner 20 by turning off the supplies of fuel and air to the burner head; thirdly, the inlet flow of water into the boiler 5 is stopped by adjustment of the control valve 54 and/or the pump 53 .
The linking of the control of the boiler and the control of the burner enables other more sophisticated and advantageous control techniques to be adopted. In particular, whereas a skilled person would expect the system to be programmed simply so that, whenever the water level rose, the inlet flow rate of water was reduced, that need not be the case.
Although a rise in water level in the boiler is usually a result of the amount of steam leaving the boiler per unit time being less at that time than the amount of water coming into the boiler per unit time, it is possible, paradoxically, for the rise in water level to occur even when the rate at which steam is leaving the boiler is greater than the rate at which water is coming into the boiler. As explained above, that can arise when there is a sudden demand for steam leading to a reduction in pressure in the boiler and consequent expansion of the small bubbles within the water in the boiler, causing the water to expand and thus the water level to rise. The embodiment of the invention described herein is able to identify this special circumstance as will now be described.
The reaction to an increasing water level is determined by assessing within the control system also how the steam pressure in the boiler, which is measured by the detector 56 , is changing and how the firing rate of the burner 20 , which can for example be assessed from the information in the control unit 1 of the amount of fuel being fed to the burner, is changing. The variables of water level, steam pressure and firing rate can each be sensed at one second intervals and their movements over the last twenty seconds used to assess the cause of an increase in water level.
For example, in a case where the water level is increasing at a slow rate, the pressure in the boiler is increasing at a slow rate and the firing rate is reducing, that is a good indication that the increase in water level is simply caused by a reduction in the demand for steam. Thus, in response to the control unit 1 and the controller 49 receiving signals indicative of that situation, the controller 49 acts to reduce at a slow rate the amount of water per unit time entering the boiler through the pipe 52 .
On the other hand, in a case where the water level is increasing at a fast rate, the pressure in the boiler is reducing at a fast rate and the firing rate is increasing, that is a good indication that the increase in water level is actually a result of a sudden demand for steam. Thus, in response to the control unit 1 and the controller 49 receiving signals indicative of that situation, the controller 49 may act to maintain, at its current rate, or to increase the amount of water per unit time entering the boiler through the pipe 52 .
It will be appreciated that the precise control criteria that are applied can be varied by the designer of the control system and/or by the commissioning engineer who installs the control system. For example, the system may be arranged so that, if only one probe assembly detects a water level beyond an acceptable range, the alarm and/or burner shut down procedure is commenced only after a relatively long period, for example 20 seconds, whereas, if both probe assemblies detect a water level beyond an acceptable range, the alarm and/or burner shut down procedure is commenced sooner, for example after 10 seconds. As well as selecting values for what may be regarded as a “slow” or “fast” rate of change of a variable, it is also of course possible to introduce values of other variables in the decision-making process for controlling the water level. By combining the control of the burner and the boiler as described above such arrangements become possible.
In a particularly advantageous embodiment, the controller 49 reads a water level signal from each of the probe assemblies 58 A, 58 B every tenth of a second. To form a water level signal the highest and lowest values are taken from ten consecutive readings from a probe and one tenth of the difference between the values is added to the lowest value to define what is then regarded as the value for that probe. The same procedure is carried out for the other probe and the two values so obtained averaged to provide a good measurement of water level even when the water is turbulent. We have found that taking only one tenth of the difference between the values is appropriate: a characteristic of a typical wave in a boiler is that peaks of the wave are significantly narrower than troughs; for that reason and because of other forms of turbulence, the peaks in the turbulent water contain relatively little water. Thus, in this particular embodiment a water level reading is generated every second; that reading may itself then advantageously be combined with, say, nine other similar readings to provide an average reading that covers a ten second period. That average reading may be updated at any selected rate down to once per second.
The readings from each probe are also used in this particularly advantageous embodiment to detect turbulence. As will now be understood, the probe assemblies 58 A, 58 B can be expected to give readings with short term variations when there is turbulence; more particularly the readings can be expected to fluctuate considerably over a period of a second when there is turbulence. The control system already described is knowledgeable of the pressure in the boiler and the water temperature and therefore knows whether or not the water should be boiling and therefore turbulent. Changes in water level of 2.5 mm or more in the course of one second may be regarded as indicative of turbulence and thus it is possible to arrange for the control system to conduct a further check that the probe assemblies 58 A and 58 B are operating properly. In the event of a conflict between the inputs, an alarm may be sounded and/or the burner 20 turned off.
Some degree of tolerance of a difference between the readings from the probe assemblies 58 A and 58 B is desirable, but it is also desirable that if the readings are far apart and remain far apart for a period long enough to allow for transient variations, then an alarm is sounded and/or the boiler 20 turned off. For example, the system may be arranged to allow for a disparity in water level readings from the respective probe assemblies of up to 50 mm for up to 20 seconds.
The control system described above is also able to assess the amount of steam per unit time that is leaving the boiler and, therefore, can dispose with the need for one or more steam flow meters. The assessment is accomplished by assessing all the energy input per unit time into the burner and boiler and the energy output per unit time other than in the steam. The difference between the energy input and the energy output as so assessed is of course a measure of the energy that has been put into the water/steam in the boiler. Provided the approximate temperature of the water passed into the system is known and the temperature and pressure of the steam are also known it becomes possible to calculate the mass flow rate of the steam. The accuracy with which the energy inputs and outputs are assessed is a matter of design choice, but one particular example is given below.
The energy input to the system is regarded as consisting exclusively of the heat generated from combustion of the fuel in the burner 20 . The control unit 1 is able to compute the amount of fuel being combusted and, if desired, can also take into account the exhaust gas analysis results from the analyser 37 to arrive at the rate of energy input at any one time. During commissioning of the control unit 1 , a calibrated fuel meter may be used in order that the control unit 1 is able to store a value of the fuel flow rate and/or heat energy input corresponding to each of a plurality of settings of the fuel valve. The control unit 1 is then able to arrive at appropriate values for any intermediate settings by interpolation.
The energy outputs from the system, apart from the steam are regarded as comprising the following:
i) the energy in the hot exhaust gases after they have passed through the boiler; ii) losses from the burner and boiler in heat that is transferred to the surroundings via radiation, conduction and convection.
The control unit 1 is informed of the temperature of the exhaust gases from the exhaust gas analyser 37 and is able to compute the flow rate of exhaust gases from the amounts of fuel and/or air being fed to the burner. For the losses from the burner and boiler, it is assumed that a fixed percentage of the heat input (in a particular example 0.25%) is lost when the burner is running at maximum firing rate and that the amount of heat lost remains the same at lower firing rates so that if the burner is turned down to, for example, one quarter of its maximum firing rate the percentage loss increases fourfold (in the particular example to 1%).
Thus the control unit 1 is able to assess the energy input into the water in the boiler. From the controller 49 the temperature of the water fed into the boiler is known and the temperature and pressure of the steam leaving the boiler are also known. The heat required to heat water (specific heat) to convert water to steam (latent heat) and to bring steam to a certain temperature and pressure is of course all well established and therefore the data available from the controller 49 when taken with that from the control unit 1 enables the new flow rate of the steam to be computed.
Extra work is required during initial commissioning of the system to calibrate the control unit 1 and the controller 49 so that they provide a good indication of the steam flow rate, but once the commissioning process has been completed and appropriate values stored in look-up tables, the computation of the steam flow rate is automatic.
Thus it can be seen that by linking together the control of the burner and boiler an especially advantageous control system can be provided.
Whilst one particular example of a system has been described, it should be understood that the system may be varied in many respects. For example, in the described embodiment the control unit 1 and the controller 49 are separate physical units; it is, however, possible to locate the controller 49 within the control unit 1 and indeed, if desired, the controller 49 may be integrated wholly into the control unit 1 , so that for example they share the same microprocessor. | A method of controlling the operation of a pressurised steam boiler ( 50 ) heated by a burner ( 20 ), which includes the steps of a) monitoring the level of water in the boiler ( 50 ), b) monitoring the pressure of steam in the boiler ( 50 ), c) monitoring the firing rate of the burner ( 20 ), and d) controlling the flow rate of water into the boiler ( 50 ) having regard to the signals resulting from a) and b) and, at least for some signal conditions, also having regard to signals resulting from c). The level of water is detected by a pair of capacitance probe assemblies ( 58 A and 58 B). | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a divisional application of Ser. No. 10/691,790, filed Oct. 23, 2003, now U.S. Pat. No. 7,363,763, and entitled COMBUSTOR, the disclosure of which is incorporated by reference herein in its entirety as if set forth at length.
BACKGROUND OF THE INVENTION
This invention relates to combustors, and more particularly to combustors for gas turbine engines.
Gas turbine engine combustors may take several forms. An exemplary class of combustors features an annular combustion chamber having forward/upstream inlets for fuel and air and aft/downstream outlet for directing combustion products to the turbine section of the engine. An exemplary combustor features inboard and outboard walls extending aft from a forward bulkhead in which swirlers are mounted and through which fuel nozzles/injectors are accommodated for the introduction of inlet air and fuel. Exemplary walls are double structured, having an interior heat shield and an exterior shell. The heat shield may be formed in segments, for example, with each wall featuring an array of segments two or three segments longitudinally and 8-12 segments circumferentially. To cool the heat shield segments, air is introduced through apertures in the segments from exterior to interior. The apertures may be angled with respect to longitudinal and circumferential directions to produce film cooling along the interior surface with additional desired dynamic properties. This cooling air may be introduced through a space between the heat shield panel and the shell and, in turn, may be introduced to that space through apertures in the shell. Exemplary heat shield constructions are shown in U.S. Pat. Nos. 5,435,139 and 5,758,503. Exemplary film cooling panel apertures are shown in U.S. Patent Application Publication 2002/0116929A1 (now U.S. Pat. No. 6,606,861) and U.S. patent application Ser. No. 10/147,571 (now U.S. Pat. No. 7,093,439), the disclosures of which are incorporated by reference as if set forth at length.
Exemplary combustors are operated in a rich-quench-lean (RQL) mode. In an exemplary RQL combustor, a portion of the fuel-air mixing and combustion occurs in an upstream portion of the combustor in which the fuel-air mixture is rich (i.e., the spatial average composition is greater than stoichiometric). In this portion of the combustor, the fuel from the nozzles mix with air from the swirlers and participative cooling air in the fore portion of the combustor. In an intermediate quench portion, additional air flow (“process air”) is introduced through orifices in the combustor walls to further mix with the fuel-air mixture and, over a short axial distance, transition the mixture to lean (i.e., less than stoichiometric) on a spatially averaged basis. This is often termed quenching of the reaction as, given typical fuel-air ratios, most of the energy in the fuel has been converted by reacting. In a downstream region, the mixture is lean and diluted to the design point overall fuel-air ratio as participative cooling further dilutes the mixture. An exemplary RQL combustor is shown in the aforementioned U.S. '929 publication.
SUMMARY OF THE INVENTION
One aspect of the invention involves a gas turbine engine combustor. A forward bulkhead extends between inboard and outboard walls and cooperates therewith to define a combustor interior volume or combustion chamber. At least one of the walls has an exterior shell and an interior shell including a number of panels. Each panel has interior and exterior surfaces and a perimeter having leading and trailing edges and first and second lateral edges. A number of cooling passageways have inlets on the panel exterior surface and outlets on the panel interior surface. A rail protrudes from the exterior surface and is recessed from the leading edge by 3-10 mm along a majority of the leading edge.
In various implementations, the rail may contact the shell. The first wall may be the outboard wall. The inboard wall may have a similar structure. The shell may have a number of apertures positioned to direct cooling air against the panel exterior surface between the leading edge and the rail. The apertures may be positioned to preferentially direct such cooling air along areas circumferentially aligned with fuel injectors. The rail may be recessed along the entire leading edge by at least 3.5 mm. There may be a gap between the exterior surface and the shell having a height of 1-3 mm.
Another aspect of the invention involves a gas turbine engine combustor where at least one of the heat shield panels has a number of pins protruding from the exterior surface toward the shell and the shell has a number of holes for directing air to a space between the shell and the panel and adapted for preferentially directing the air toward leading edge portions of first stage vanes of a turbine section. Such panels may be the aft circumferential array of panels in the combustor. The holes may include a number of alternating first and second groups of holes having at least partial differences in at least one of size and distribution. The pins may contact the shell. The pins may be in a continuous uninterrupted array along the panel. The pins may be in a number of circumferential rows, each row being out of phase with any adjacent row.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description and claims below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal sectional view of a gas turbine combustor.
FIG. 1A is an enlarged view of leading portion of an outboard wall of the combustor of FIG. 1 .
FIG. 1B is an enlarged view of trailing portion of the outboard wall of the combustor of FIG. 1 .
FIG. 2 is an exterior view of a forward heat shield panel of the combustor of FIG. 1 .
FIG. 3 is an exterior view of an aft heat shield panel of the combustor of FIG. 1 .
FIG. 4 is an exterior view of a portion of a shell of the combustor of FIG. 1 .
Like reference numbers and designations in the various drawings indicate like elements.
DETAILED DESCRIPTION
FIG. 1 shows an exemplary combustor 20 positioned between compressor and turbine sections 22 and 24 of a gas turbine engine 26 having a central longitudinal axis or centerline 500 (spacing contracted). The exemplary combustor includes an annular combustion chamber 30 bounded by inner (inboard) and outer (outboard) walls 32 and 34 and a forward bulkhead 36 spanning between the walls. The bulkhead carries a circumferential array of swirlers 40 and associated fuel injectors 42 . The exemplary fuel injectors extend through the engine case 44 to convey fuel from an external source to the associated injector outlet 46 at the associated swirler 40 . The swirler outlet 48 thus serves as an upstream fuel/air inlet to the combustor. A number of sparkplugs (not shown) are positioned with their working ends along an upstream portion 54 of the combustion chamber 30 to initiate combustion of the fuel/air mixture. The combusting mixture is driven downstream within the combustor along a principal flowpath 504 through a downstream portion 56 to a combustor outlet 60 immediately ahead of a turbine fixed vane stage 62 .
The exemplary walls 32 and 34 are double structured, having respective outer shells 70 and 72 and inner heat shields. The exemplary heat shields are formed as multiple circumferential arrays (rings) of panels (e.g., inboard fore and aft panels 74 and 76 and outboard fore and aft panels 78 and 80 ). Exemplary panel and shell material are high temperature or refractory metal superalloys optionally coated with a thermal and/or environmental coating. Alternate materials include ceramics and ceramic matrix composites. Various known or other materials and manufacturing techniques may be utilized. In known fashion or otherwise, the panels may be secured to the associated shells such as by means of threaded studs 84 integrally formed with the panels and supporting major portions of the panels with major portions of their exterior surfaces facing and spaced apart from the interior surface of the associated shell. The exemplary shells and panels are foraminate, passing cooling air from annular chambers 90 and 92 respectively inboard and outboard of the walls 32 and 34 into the combustion chamber 30 . The exemplary panels may be configured so that the intact portions of their inboard surfaces are substantially frustoconical. Viewed in longitudinal section, these surfaces appear as straight lines at associated angles to the axis 500 . In the exemplary embodiment, the interior surface panel of inboard fore panel 74 is aftward/downstream diverging relative to the axis 500 at an angle θ 1 . The interior surface of the inboard aft panel 76 is similarly diverging at a greater angle θ 2 . The interior surface of the fore outboard panel 78 is aftward/downstream diverging at a very small angle θ 3 . The interior surface of the aft outboard panel 80 is very close to longitudinal, shown aftward/downstream converging at a small angle θ 4 . In the exemplary embodiment, the angles θ 1 and θ 3 are such that the cross-section of the chamber upstream portion 54 is approximately constant in terms of linear sectional dimension but aftward/downstream diverging along the central flowpath in terms of annular cross sectional area. The chamber downstream portion 56 is convergent, although at a much lesser rate. In the exemplary embodiment, the junctions between fore and aft panels substantially define a dividing area 510 between fore and aft combustion chamber portions 54 and 56 . Exemplary values for θ 1 , θ 2 , θ 3 , and θ 4 are: 11.894°, 29.074°, 11.894°, and 0.785°, respectively.
FIGS. 1A and 2 show further details of the exemplary fore outboard panel 78 (the fore inboard panel 74 being generally similarly formed). The panel has a main body portion 100 having interior (hot-facing the combustion chamber) and exterior (cold-facing away from the combustion chamber) surfaces 102 and 104 ( FIG. 1A ). The body is circumscribed by a perimeter having leading and trailing portions 106 and 108 and connecting lateral portions 110 and 112 ( FIG. 2 ). A rail system extends from the exterior surface 104 and includes a first portion 114 recessed from the leading edge by a distance D ( FIG. 1A ). The distal rim portions of the rail system contacts the shell interior surface so that the portions of the rail system have a height H coincident with the separation between major portions of the panel exterior surface and shell interior surface. Exemplary values for D and H are 3.8 mm and 1.7 mm. The rail system further includes a second portion 116 along the trailing edge, lateral perimeter portions 118 and 120 along the lateral edges 110 and 112 , and intermediate longitudinal rails 122 , 124 , and 126 . The rail system also includes portions 130 and 131 surrounding combustion process air (mixing/dilution) apertures or orifices 132 and 133 which provide direct communication through aligned corresponding apertures in the associated shell to introduce air from the associated chamber 92 or 90 into the combustion chamber to lean the combustion gases. In the illustrated embodiment, the first orifices 132 are larger than the second orifices 133 . These orifices circumferentially alternate along the panel. The respective large and small orifices of the inboard panels are exactly out of phase with those of the outboard panels. Accordingly, a large orifice of one panel will be circumferentially aligned with a small orifice of the other. This creates intermeshing air streams which further enhances mixing within the combustor. The panels further include arrays of film cooling holes 140 extending between the surfaces 104 and 102 ( FIG. 1A ). In the illustrated embodiment, air is passed through holes 142 in the shell 72 to impingement cooling spaces 144 between the shell interior surface 146 and the panel body exterior surface 104 . These holes 142 may be positioned and oriented to direct streams of air against intact portions of the surface 104 to provide impingement cooling of such surfaces. After such direction, the gas passes through the holes 140 which are angled so that their discharge provides a desired film cooling of the surface 102 . The shell 72 further includes a group of holes 150 positioned between the leading edge 106 and rail portion 114 . These holes are positioned so that their discharge impacts the surface 104 ahead of the rail 114 and flows forward, wrapping around the leading edge 106 and then aftward between the surface 102 and an adjacent portion 160 of a heat shield panel 162 on the bulkhead. The holes 150 serve to initiate film cooling along the panel interior surface and are discussed in further detail below.
FIGS. 1B and 3 show further details of the aft outboard heat shield panel 80 (the aft inboard panel may be similar). Many details may be similar to those of the fore panel and, therefore, are not discussed in as great length. For purposes of identification, the panel 80 has a body 180 with interior and exterior surfaces 182 and 184 and leading, trailing, and two lateral edges 186 , 188 , 190 , and 192 . The exemplary panel has a rail system with portions along the leading and lateral edges, intermediate longitudinal portions, and a portion 200 forwardly recessed from the trailing edge 188 by a distance D 2 . The rail system may have a similar height as with the fore panel. Exemplary values for D 2 are 12.4 mm for an outboard panel and 8.7 mm for an inboard panel in the exemplary configuration. The choice of D 2 will be based on how close the last row of cooling holes can be placed to the combustor exit. This, in turn, is largely determined by combustor exit sealing geometry and the nature of the drilling tool to be used. In the exemplary embodiment, such consideration places the holes farther forward of the aft panel trailing edge along the outboard wall than along the inboard wall, thus the diameter difference. Between the portion 200 and the trailing edge 188 , an array of pins 202 extend from the exterior surface 184 toward and contacting the shell interior surface. In the exemplary embodiment, the pin array extends aft from approximately a midpoint of this region. In the exemplary embodiment, the pin array is substantially uninterrupted and includes multiple rows (e.g., four) with the pins of each row being offset (e.g., exactly out of phase) from the pins of the adjacent rows. A chamber 204 is formed between the pin array and the rail portion 200 . This space is fed with air from the chamber 92 through holes 206 extending at an angle θ 5 to the local shell surface. An exemplary θ 5 is 46.955°.
The size and distribution of the holes 150 and 206 of FIGS. 1A and 1B , respectively, may be selected to achieve desired cooling properties. FIG. 4 shows an exterior surface 210 of the outboard shell 72 . The view shows process air apertures 212 and 213 , respectively, coextensive with the associated apertures 132 and 133 of FIG. 2 and circular and elongate mounting apertures 214 and 215 accommodating the panel mounting studs 84 (shown with nuts removed for purposes of illustration). The circular apertures 214 serve to register the central pair of studs of each associated panel while the elongate nature of the holes 215 accommodate lateral pairs to permit local circumferential relative movement upon thermal expansion/contraction of elements. FIG. 4 shows exemplary single-row arrays of the holes 150 and 206 . The row of holes 150 is divided into two alternating groups of holes 220 and 222 . The holes of these exemplary groups are of substantially equal cross-section. However, the on-center spacing of the first group is smaller (e.g., 30%-70%) to provide an associated region of enhanced flow. Each of these enhanced flow regions is aligned between an associated pair of the fuel injectors/swirlers to provide enhanced cooling to counter the concentration of heat generated immediately downstream of overlapping spray zones such injector/swirlers. In the exemplary embodiment, the number of holes in the first group is smaller than that in the second group and the circumferential span of the first group is much smaller than that of the second (e.g., less than 30% and, more narrowly, less than 20%). Exemplary diameters for these holes are 0.6 mm. Exemplary on-center spacing of the first and second groups is 1.8 mm and 3.5 mm. Other permutations of spacing, size, shape, and the like may be utilized as may be variations of such parameters within groups.
The row of holes 206 is divided into groups 230 and 232 , respectively, providing more and less concentrated cooling. Each enhanced flow group 230 is associated with a corresponding vane 234 of the stage 62 . The positioning of this group along with the associated angle θ 5 ( FIG. 1B ) relative to the shell interior surface may be used to substantially counteract a bow wave of the vane 234 . The bow wave or “horseshoe vortex” results from the interaction of the combustor output with the vane 234 . As flow from the combustor approaches the vane leading edge 238 (which may be coincident or nearly coincident with the forward extremity 236 ) it stagnates at the leading edge to form a localized region of high static pressure. This stagnation creates high spatial pressure gradients and complex three-dimensional flows particularly in the region where the vane airfoil meets the (outboard) endwall 240 ( FIG. 1 ) and (inboard) platform 242 ( FIG. 1 ). The three-dimensional flows at the vane leading edge tend to wrap around leading edge in a U-shape with one leg along the pressure side and one leg along the suction side thus the term “horseshoe vortex”. The pressure gradients make it difficult to cool the endwalls/platforms and adjacent portions of the vane airfoil, as the cooling flow will tend to be directed toward regions of lower static pressure. Additionally, the three-dimensional flows/gradients may drive hot combustor gases back toward the combustor walls.
In the exemplary embodiment, the number, shape, and angling of the holes/passageways 206 helps to direct and meter the flow (subject to having sufficient numbers and size of pins) to provide desired cooling performance while having sufficient velocity and mass flow to counter the bow wave yet not having so great a mass flow so as to constitute an excessive inefficiency. The exemplary group 230 is positioned ahead of the forwardmost extremity 236 of the vane airfoil, shifted slightly toward the pressure side thereof. In the exemplary embodiment, the circumferential spacing of vanes 234 is much smaller than that of the fuel injectors and, accordingly, the circumferential length of the pairs of hole groups are correspondingly smaller. Thus, for example, the circumferential span of the groups 230 and 232 may be nearly equal. Flow concentration is achieved, in the exemplary embodiment, by having larger cross-section holes in the group 230 as well as having a smaller on-center spacing in that group. Exemplary diameter and on-center spacing for the holes of the groups 230 are 1.0 mm and 5.9 mm for an outboard panel and 1.0 mm and 5.1 mm for an inboard panel. Exemplary diameter and on-center spacing for the holes of the groups 232 are 1.4 mm and 3.1 mm for an outboard panel and 1.3 mm and 3.3 mm for an inboard panel. An exemplary circumferential span of the first group is between 60 and 150% that of the second, more narrowly, 80 and 120%.
One or more embodiments of the present invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, when applied as a reengineering of an existing combustor, details of the existing combustor will influence details of the particular implementation. Accordingly, other embodiments are within the scope of the following claims. | A gas turbine engine combustor has forward bulkhead extending between inboard and outboard walls and cooperating therewith to define a combustor interior volume or combustion chamber. At least one of the walls has an exterior shell and an interior shell including a number of panels. Each panel has interior and exterior surfaces and a perimeter having leading and trailing edges and first and second lateral edges. A number of cooling passageways have inlets on the panel exterior surface and outlets on the panel interior surface. The shell has a plurality of holes for directing air to a space between the shell and heat shield and adapted for preferentially directing said air toward leading edge portions of first stage vanes of a turbine section. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to throwing wheels of the type used for abrasive blast cleaning or peening wherein a throwing wheel includes a plurality of throwing vanes mounted upon a runnerhead in a vane receiving channel. Such throwing vanes must be locked in the runnerhead against the action of centrifugal force during high speed rotation. More particularly, the invention relates to a unique improvement of the vane locking apparatus shown in FIGS. 23-30 in U.S. Pat. No. 3,241,266 which was granted to Joseph E. Bowling, Jr., on Mar. 22, 1966.
The vane locking mechanisms of the prior art, as exemplified by U.S. Pat. No. 3,241,266 properly perform the function of locking the throwing vanes in the runnerhead. However, a very serious disadvantage of the prior art is inherent in the fact that particles of grit, abrasive throwing media and the like cause the locking pins to jam in the locking pin hole and creates a serious problem during maintenance of the throwing wheel. As is well known, the throwing vanes are subjected to highly abrasive actions during operation and it becomes necessary to replace the throwing vanes either weekly, daily or sometimes hourly. There have been occasions when the locking pins have become so jammed that it takes five to seven minutes of frustrating effort to remove the locking pin so that a worn out throwing vane can be replaced.
SUMMARY OF THE INVENTION
The present invention provides a runnerhead for a throwing wheel wherein the runnerhead comprises a plate member having a face and at least one vane receiving channel formed in the face for receiving a throwing vane, and a locking means is provided for locking the throwing vane in the vane receiving channel, the locking means including a locking pin hole for receiving a locking pin, the hole being formed in the plate member and extending angularly inwardly from the face. The improvement is comprised of providing a locking pin release channel formed in the plate member contiguous with the locking pin hole.
More particularly, the locking pin release channel and the locking pin hole have respective axial center lines disposed parallel to each other and the locking pin release channel spans the locking pin hole for allowing a locking pin to be tilted from the locking pin hole in a plane perpendicular to the vane receiving channel. As a result, maintenance procedures which heretofore required five to seven minutes can be promptly performed in a matter of a few seconds, or less.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary plan view of a portion of a throwing wheel and a vane locking pin hole provided with a locking pin release channel according to the present invention.
FIG. 2 is a sectional view, taken on line 2--2 of FIG. 1, and illustrates the parallel relationship of the axial center lines of the locking pin hole and the locking pin release channel.
FIG. 3 is a view similar to FIG. 2 and shows a throwing vane and a locking pin in operative location.
FIG. 4 is a fragmentary edge view taken on line 4--4 of FIG. 2.
FIG. 5 is a fragmentary view, similar to FIG. 3, and illustrates the simplicity of removing the locking pin from the locking pin hole during replacement of the throwing vane.
DETAILED DESCRIPTION OF THE INVENTION
A portion of a throwing wheel, generally indicated by the numeral 10 includes a runnerhead 12 which is provided with a series of throwing vanes 14. The throwing vanes 14 are shown as being radially disposed on the runnerhead 12 but it is to be understood that such throwing vanes may be of different configurations and be disposed on the runnerhead other than radially.
As is best shown in FIGS. 1, 2 and 4, the runnerhead 12 is provided with a series of conventional dove-tailed vane receiving channels 16 such that the throwing vanes 14 can be slid radially inwardly of the runnerhead 12 in a manner well known in the prior art as exemplified by U.S. Pat. No. 3,241,266. During operation of the throwing wheel 10 the runnerhead 12 is rotated about a central axis indicated by the numeral 18 in FIG. 1. In order to keep the throwing vanes 14 in proper location and to preclude movement of the throwing vanes out of the vane receiving channels 16 because of centrifugal force, each vane receiving channel 16 is provided with a locking pin hole 20 which is, preferably, bored or drilled into the runnerhead 12 along the vane receiving channel 16 and tapers downwardly and inwardly at an angle which may be approximately 30° to a top face 22 of the runnerhead 12. As is shown, the locking pin hole is cylindrical for receiving a cylindrical locking pin 24; however, it is to be understood that the locking pin 24 may have other configurations such as being square, triangular, oval, etc., and the locking pin hole 20 will have a corresponding configuration.
It is well known that during assembly of the throwing wheel pin the throwing vanes 14 are moved radially inwardly of the runnerhead 12 past their normal operating location, such as is illustrated in FIG. 5, and the locking pin 24 is then located within the locking pin hole 20 and the throwing vane 14 is then moved radially outwardly until it contacts the locking pin 24 as is best shown in FIG. 3. A locking ring 30, as is best shown in FIGS. 1 and 3, is then fixed to the runnerhead 12 to lock the throwing vanes 14 against the locking pins 24. In this manner, the throwing vanes 14 are securely locked into operative position and are precluded from moving radially inwardly or outwardly of the vane receiving channel 16.
During maintenance procedures for replacing worn throwing vanes 14 the usual procedure is to remove the locking ring 30, move the throwing vane 14 radially inwardly, remove the locking pin 24, and slide the throwing vane 14 radially outwardly along the vane receiving channel 16. Thereafter, the steps are reversed by first sliding a new throwing vane 14 into the vane receiving channel 16, and so forth. The seemingly innocuous step of removing the locking pins of the prior art is not as simple as one might expect. Formerly, the locking pins 24 had to be removed axially because the locking pin 24 was seated in a cylindrical locking pin hole that had its outermost terminus flush with the plane of the vane receiving channel. During a typical life of a throwing vane 14, thousands of pounds, or even kilograms, of abrasive blasting particles will travel along the vane and it is not untypical that the abrasive particles or shot have an average particle size of 0.007 inch in diameter. It is essentially unavoidable that particles of this minute size become lodged in the hole occupied by the pin and wedged in between the pin and wall of the hole thereby making it difficult to remove the pin. It is a primary feature of the present invention to eliminate the possibility of the abrasive build up, but still retain a seat for the locking pin, by machining, or boring, or cutting away a portion of the wall of the conventional locking pin hole and providing a locking pin release channel 40 which allows the locking pin 24 to be leaned or tilted outwardly from the locking pin hole 20 as is best shown in FIG. 5 wherein the locking pin 24 is moved from the full line position to the dotted line position.
The locking pin release channel 40, as is best illustrated in FIGS. 1, 2 and 4, can be formed in various ways but, as an example and not as a limitation upon the invention, it is shown as being formed by a milling operation wherein, first, the locking pin hole 20 is drilled to extend angularly inwardly from the face 22, centrally located within the vane receiving channel 16, along an axial center line 42 (FIG. 2). After drilling of the locking pin hole 20 is completed, a milling tool (not shown) has its axis aligned parallel to the center line 42 and is moved perpendicular thereto until the milling tool cuts away a portion of the vane receiving channel 16 above the locking pin hole 20. The milling tool is of a larger diameter than the diameter of the locking pin hole 20 and is moved until the center line of the tool is approximately at the position indicated by the axial center line 44 in FIG. 2. As can be seen in FIGS. 1, 2 and 4, the locking pin release channel 40 is defined by side wall portions 46 and 48 and terminates at a tapered end wall 50 so as to provide an abbreviated shoulder 52 located adjacent an innermost portion of the locking pin hole 20 at a terminus of the locking pin release channel 40 thereby providing a seat for the locking pin 24.
The foregoing detailed description of a preferred embodiment of the invention is subjected to various modifications which will be obvious to those skilled in the art and it is to be understood that various changes and modifications may be made within the spirit and scope of the invention as defined by the following claimed subject matter. | A runnerhead for a throwing wheel of the type used in blast cleaning and peening operations includes a throwing vane receiving channel provided with a locking pin hole and a locking pin for locking a throwing vane in the channel and a locking pin release channel is formed in the runnerhead contiguous with the locking pin hole for allowing the locking pin to be tilted out of the locking pin hole. | 1 |
BACKGROUND OF THE INVENTION
This invention is an improvement in a known chemical process. More specifically, it concerns an improved process for making polypeptides by the coupling reaction of an amino acid azide with an amino acid compound in a substantially anhydrous reaction system.
The azides of carboxylic acids are useful chemical intermediates in processes for converting the acids into other types of compounds. For example, the Curtius rearrangement transforms an azide into the corresponding isocyanate for use in making urethanes, ureas, amides or amines. One synthesis of α-amino acids proceeds through the azide of an α-cyano acid as an intermediate. Azides are of particular interest in the Bergmann synthesis of polypeptides by the coupling reaction of an N-protected amino acid azide with a C-protected amino acid such as the ester, amide, N-substituted amide, or a solvent-soluble salt.
The latter synthesis, in particular, is of interest because of the increasingly intensive work in the field of synthetic polypeptides. These compounds offer a means for understanding the structure and mode of participation of more complex natural polypeptides and proteins in life processes and "tailor-made" polypeptides differing from naturally occurring molecules in predetermined ways provide useful new tools in biochemical and medical research. Complex, naturally occurring polypeptides such as secretin, insulin, and calcitonin have recently been synthesized in the laboratory using a progression of coupling reactions.
The Bergmann synthesis couples amino acid molecules by reacting the amino group of a carboxyl-protected amino acid compound such as the ester, amide, or salt with the acyl azide of an amino acid or peptide wherein the amino group or groups of the azide reactant are protected against undesirable side reactions by an easily removable N-protective group such as an acyl group, a toluenesulfonyl group or a urethane radical.
Generally in azide-amino acid couplings, the azide is made from the corresponding hydrazide by treatment with nitrous acid in aqueous acid (e.g., sodium nitrite plus dilute hydrochloric acid) or with an alkyl nitrite in an acidic organic medium. In both cases the azide solution must be washed with base (e.g., bicarbonate solution) to remove excess acid. This step may tend to cause racemization at the α-carbon atom of the amino acid or peptide azide. After washing with base, the azide solution is dried prior to reaction with the amino acid compound. Hence, during these manipulations which are time consuming and which must be conducted in the cold, there is greater possibility of rearrangement of the azide to the corresponding isocyanate, a side reaction which may lead to the formation of an urea instead of peptide by the following sequence of reactions: ##STR1## There are special examples in the literature of azide preparations in which, (a) a nonpolar solvent is used in conjunction with an alkyl nitrite as the nitrous acid source with the same reaction vessel and used for both the nitrosylation and coupling reactions excess acid is neutralized with an organic tertiary base; or (b) a polar solvent such as dimethylformamide is used with an inorganic nitrite and hydrochloric acid, to supply nitrous acid, a single reaction vessel is used, and excess acid is neutralized by an organic tertiary base. The present invention, however, has the advantage over the former of using an inexpensive nitrosylating source and over the latter of allowing the use of a nonpolar solvent.
So-called crown complexes of inorganic compounds with macrocyclic polyethers are described by Pedersen in U.S. Pat. No. 3,562,295. These complexes are generally suggested for use in extraction processes and diazotization and nitrosylation reactions although no examples of the latter are given and there is no mention of their possible use in anhydrous polypeptide preparations.
SUMMARY OF THE INVENTION
It has now been found that in the azide coupling reaction for making polypeptides as described above, side reactions and other disadvantages of known procedures are avoided by providing the acid azide reactant as the reaction mixture formed by nitrosylating an N-protected amino acid hydrazide in an essentially anhydrous organic solvent medium using as the source of nitrous acid an alkali metal nitrite complex with a cyclic polymer of ethylene oxide, propylene oxide of mixture thereof.
By this invention, an azide preparation and subsequent coupling of the azide can be carried out in an essentially anhydrous nonpolar solvent or other solvent which permits hydrogen bonding using an inexpensive nitrosylating agent. The entire process is conducted in a single vessel and washing of the azide solution is unnecessary since only a relatively small excess of mineral acid is required and this can be neutralized with an equivalent amount of a tertiary organic base like triethylamine or with an equivalent amount of excess amino reactant.
DETAILED DESCRIPTION
The cyclic polymer of alkylene oxide preferably consists of 4-6 ethylene oxide units and the pentamer is most preferred, because its nitrite complexes are more soluble than those of the tetramer or the hexamer. The preferred alkali metal nitrite is sodium nitrite because of its easy availability and the greater solubility of its cyclic ether complex. Other alkali nitrites such as the potassium and lithium salts are also operable in the process, however. The preferred quantity of cyclic ether is about 2.5-3 mole equivalents based on the nitrite. Lesser amounts may not completely solubilize the nitrite and so may cause slow or incomplete nitrosylation of the acid hydrazide. Larger quantities are merely wasteful. The corresponding cyclic polymers of propylene oxide and cyclic polymers containing both ethylene oxide and propylene oxide units can also be used in the same way to form the nitrite complex.
The nitrosylation process of this invention is carried out by combining the nitrite, alkylene oxide cyclic polymer, and the hydrazide in a suitable solvent which permits hydrogen bonding such as methylene chloride, chloroform, acetonitrile, dimethylformamide, and other such solvents containing at least one carbon-hydrogen bond. To the cooled solution there is then added an excess of a strong acid, preferably a strong mineral acid dissolved in an inert organic solvent. Preferred acids are those whose anhydrous solutions are readily prepared at concentrations of about 2-3 normal. Strong mineral acids or their recognized equivalents such as HCl, H 2 SO 4 , and trifluoroacetic acid are representative of the class. The amino acid ester or other C-protected amino acid compound is then added, preferably dissolved in the same solvent.
The temperature conditions and relative proportions of reactants are those customarily employed in similar known azide preparations and coupling reactions. Since an equivalent of nitrous acid is required to nitrosylate one equivalent of carboxylic hydrazide, at least one equivalent of alkali metal nitrite is necessary for completion of this reaction. A substantial excess, i.e., >5% of nitrite, would lead to an excess of nitrous acid which if not destroyed would attack an amino acid reactant when it is added to the reaction mixture thereby diminishing it and producing complex by-products. An equivalent of acid is necessary to generate an equivalent of nitrous acid. An excess of acid outside the preferred range may tend to destroy acid-sensitive protective group(s) of the carboxylic hydrazide which is undesirable. The preferred amount of amino acid reactant for a subsequent coupling reaction is the amount necessary to neutralize excess acid plus an equivalent amount required for the coupling reaction. If the amount of amino acid reactant is less than the preferred amount, there will be an insufficient amount of it available for the coupling reaction since irreversible neutralization with excess acid will occur first. If the amount of amino reactant substantially exceeds the preferred limit, i.e., >50%, the resulting basic condition of the medium may tend to cause racemization of the carboxylic azide. If the amino reactant is precious then it is preferred that excess acid be neutralized with an equivalent of tertiary amine. The preferred temperature range for the nitrosylating step is -15° to -25°. Working above this temperature may tend to cause rearrangement of the axide to an isocyanate. Further, a protective group such as the tertiary butyloxycarbonyl radical may be susceptible to acid attack when operating above the preferred range. Nitrosylating below the preferred range may lower the solubility of the reactants which is undesirable. The preferred temperature for the amino ester coupling step is -15° to -20° for the first 1-2 hours, then 0°-5° for the remainder of the reaction. Coupling above the preferred temperature may cause undesirable side reactions and coupling below the preferred temperature may lower the solubility of the reactants and slow the reaction rate.
EXAMPLE
Methyl ε-aminocaproate hydrochloride and N-carbobenzyloxy-ε-aminocaproic acid were prepared by procedures described by Garmaise et al., J. Am. Chem. Soc., 80, 3332 (1958) and Zahn et al., Chem. Ber., 90, 320 (1957) respectively.
Methyl N,N'-Dicarbobenzyloxy-ε-aminocaproyl-L-lysinate
To a stirred suspension of 7.0 g. (0.021 mole) of methyl Nε-carbobenzyloxy-L-lysinate hydrochloride and 5.6 g. (0.021 mole) of N-carbobenzyloxy-ε-aminocaproic acid in 50 ml. of methylene chloride was added 2.95 ml. (0.021 mole) of triethylamine. The resulting solution was cooled to 0° C. whereupon 4.6 g. (0.022 mole) of dicyclohexylcarbodiimide was added. Stirring was continued at 0° for 3 hours and the reaction mixture was filtered, the filter residue (dicyclohexylurea) was rinsed with 30 ml. of CH 2 Cl 2 . The combined filtrate and rinse was washed successively with 1N HCl, water, bicarbonate solution and water, dried (MgSO 4 ) and freed of solvent in vacuo. The residue, a thick oil 11.7 g., crystallized on standing and was recrystallized from dilute ethanol. There was obtained 8.1 g. (71%) of pale cream white solid, m.p. 89°-91°. The analytical sample was obtained by another recrystallization from dilute alcohol and dried in vacuo over solid KOH, m.p. 92°-94.5°, [α] D 25 = -11.9° ± 0.6° (0.62 g. in 100 ml. ethanol solution). Infrared and elemental analyses were consistent with the assigned structure.
N,N'-Dicarbobenzyloxy-ε-aminocaproyl-L-lysine Hydrazide
To a warm solution of 7.30 g. (0.0135 mole) of methyl N,N'-dicarbobenzyloxy-ε-aminocaproyl-L-lysinate in 50 ml. of warm absolute ethanol was added 20 g. (0.06 mole) of 95% hydrazine. The resulting solution on cooling and standing at room temperature produced a white precipitate which was collected after about ca. 15 hours, washed with alcohol and dried, 6.9 g. (59%), m.p. 167°-168° and 169°-170° after recrystallization from absolute ethanol, [α] D 25 - 3.7° (1.08 g. in 100 ml. DMF solution). Elemental analysis confirmed the identity of the product.
Methyl N,N'-Dicarbobenzyloxy-ε-aminocaproyl-L-lysyl-ε-aminocaproate
To a stirred solution of 72 mg. (1.04 mmole) of sodium nitrite and 610 mg. (2.77 mmoles) of ethylene oxide cyclic pentamer in 7 ml. of methylene chloride was added 542 mg. (1.0 mmole) of N,N'-dicarbobenzyloxy-ε-aminocaproyl-L-lysine hydrazide. This stirred suspension was cooled to -22° C. whereupon 597 mg. (1.88 m equiv.) of HCl in dimethoxyethane (3.1 m equiv. HCl/g. solution) was added dropwise during 5 min., the reaction temperature being maintained between -22° to -17° C. as complete solution resulted. After stirring with continued cooling at -20° to -17° C. for 20 min. the solution was negative to starchiodide paper indicating complete consumption of nitrous acid. Several minutes later a solution of 300 mg. (2.07 mmoles) methyl ε-aminocaproate in 3 ml. of methylene chloride was added during 5 min. at -20° to -17° C. After stirring at ca. -20° C. for 1 hour, the reaction mixture was refrigerated for two days. It was filtered under suction and the filtrate evaporated leaving a semi-solid residue which was triturated with water, collected on a filter and dried yielding 658 mg. of crude white product. This was dissolved in 13 ml. of methylene chloride and filtered to remove some insoluble material; evaporation of the filtrate left 649 mg., of which 624 mg. was recrystallized from 10 ml. of ethyl acetate and 15 ml. of ether, 555 mg. of white solid was recovered. A 551 mg. portion of this was then chromatographed on a column of silica gel which was developed with 100 ml. of methylene chloride followed by 500 ml. of methylene chloride containing 2.5% (by volume) methanol. Fractions containing pure product, as indicated by thin-layer chromatography, were combined and evaporated leaving 478 mg. of white crystalline solid of methyl N,N'-dicarbobenzyloxy-ε-aminocaproyl-L-lysyl-ε-aminocaproate, m.p. 101°-102° C. The yield was 76% (after adjustment for the small amounts removed during the purification steps). The product was identified by infrared spectrum and mixed melting point with a known sample prepared by a conventional coupling procedure. This compound, when converted to the phosphoric acid salt of the amino ester, has fungicidal activity and kills organisms such as Trichoderma sp. when applied as a water solution of 500 ppm. or greater concentration. In a coupling reaction similar to that shown above, N-p-tolylsulfonylglycine hydrazide is reacted with an alkali metal nitrite-ethylene oxide cyclic polymer and HCl by the procedure of this invention to make N-p-tolysulfonylglycine azide and the methyl ester of alanine is added to the cooled reaction mixture to produce N'-(N-p-tolylsulfonylglycyl)alanine. This and other similar reactions are also carried out in the same way using the complex of an alkali metal nitrite with a propylene oxide cyclic polymer or the cyclic polymer of mixed ethylene and propylene oxides. Other such N-protected amino acid azides are readily prepared by this procedure and directly reacted in anhydrous systems with amino acid esters as described herein to make polypeptides in good yield and without significant side reactions. Polypeptides such as the ethyl ester of N-p-toluenesulfonyl-S-benzyl-L-cysteinyl-L-tyrosyl-L-leucine and the methyl ester of N-carbobenzyloxy-L-leucyl glycine are thereby obtained. | The preparation of the azide of a carboxylic acid by reacting the hydrazide of the acid with nitrous acid is facilitated by using the organic solvent-soluble complex of an alkali metal nitrite with an ethylene oxide or propylene oxide cyclic polymer as the nitrous acid source. The improvement is particularly useful as a means for making peptides by the coupling reaction of an amino acid ester or other derivative with an acid azide in an anhydrous reaction medium. | 2 |
FIELD OF THE INVENTION
The present invention relates to an improved system for collecting and stacking round hay bales on a flat bed trailer, particularly for use in agricultural applications such as farming or the like.
BACKGROUND OF THE INVENTION
It is common practice to transport hay and other agricultural products from one location to another as needed. Hay is usually baled into large cylindrical bales secured with twine that will often weigh several hundred kilograms depending on its size and moisture content. It is well known that moving these bales with purely manual labor is very difficult and as a result a mechanical apparatus to retrieve, transport and unload these most hay bales is required.
In the past, the collection and stacking of hay bales is typically achieved with the use of various lifting and transporting equipment and the simultaneous work of at least two operators. For example, when collecting round hay bales in a field, one operator may drive a tractor with an attached flat bed trailer and a second operator will follow with a forklift or other appropriate lifting equipment. The first tractor moves the flatbed trailer close to one or more hay bale(s), pausing to let the forklift or other appropriate lifting equipment stack the hay bale(s) on the flatbed trailer. This method for the collection and stacking of hay bales is undesirable as it requires the labor of two operators and requires two pieces farm equipment.
Alternatively, farmers may choose to collect and stack hay bales with a single towing system. In this case, the farmer will typically tow a flat bed trailer with a tractor having a front-end forklift or other appropriate lifting device. This method requires the operator to sequentially stop at select areas in the fields, manually disconnect the trailer, use the forklift to load and stack nearby bale(s) onto the flat bed trailer and then reconnect the flat bed trailer before continuing to the next area where a number of bales may be located. While this collection method can eliminate a second operator, this method is undesirable as it is time consuming and laborious for one person to complete.
Furthermore, once all hay bales have been collected and transported to a desired unloading or storage area, the process of offloading any hay bales from a flat bed trailer requires a forklift or other appropriate lifting equipment and like the loading processes described above is time-consuming.
Further still, forklifts or other lifting equipment will often cause damage to hay bales. For example, a forklift may pierce the hay bale or sever any attachments holding the bale together such that additional work may be required to repair or remove damaged bales.
Moreover, farmers may cover hay bales in a wrapping material when producing haylage, silage or the like. For the fermentation of silage, haylage or the like to be effective, the wrapping must remain intact. Often forklifts and other appropriate lifting equipment handles bales roughly resulting in tears, punctures or the like that inhibit the formation of silage, haylage or the like.
As a result, there has been a need for hay bale collection equipment allowing a single operator to efficiently move around a field collecting multiple hay bales without getting out of their tractor and that provides a reliable but simple system that minimizes the risk of damage to a hay bale.
A review of the prior art indicates that while various systems for collecting and transporting hay bales have been provided in the past, there continues to be a need for new designs of such systems that provide improvements over these past systems. For example, the prior art shows various hay bale collection and lifting systems including U.S. Pat. No. 4,459,075, U.S. Pat. No. 6,935,827, US Patent Application 2003/0031533, U.S. Pat. No. 6,478,522, U.S. Pat. No. 7,004,706, U.S. Pat. No. 5,333,981, U.S. Pat. No. 4,329,102, U.S. Pat. No. 4,076,138, U.S. Pat. No. 5,062,757, U.S. Pat. No. 7,252,190, US Patent Application 2006/004657, U.S. Pat. No. 7,241,098, U.S. Pat. No. 6,312,205, U.S. Pat. No. 7,090,456, and U.S. Pat. No. 7,210,888.
SUMMARY OF THE INVENTION
Accordingly, it is the object of the present invention to provide a hay bale collection and stacking system requiring only one operator who does not have to exit their tractor.
It is another object of the present invention to provide a hay bale stacking and collection system that can load multiple stacks of hay bales onto one flatbed trailer.
It is still a further object of the present invention to provide a hay bale stacking and collection system that can offload all hay bales in an efficient manner.
It is yet another object of the present invention to provide a hay bale stacking system that is simple, reliable and robust in order to prevent malfunction.
In accordance with the invention, in a first embodiment a hay bale stacking system for operative attachment to a trailer for lifting and stacking hay bales on the trailer is provided, the hay bale stacking system comprising:
a main pivot arm having a first end and a second end, the first end pivotally connected to a first side of the trailer, the main pivot arm including a main track and a guide track; a cradle having a track pivot wheel operably mounted within the main track and a cradle pivot wheel operatively mounted on the guide track, the cradle for operable support and lifting of a hay bale from the ground to the trailer; a hydraulic system for moving the cradle along the main track, for rotating the cradle with respect to the main pivot arm and for lifting the main pivot arm; wherein the main pivot arm, cradle and hydraulic system are operable between a ground position and first and second positions where two hay bales are unloaded to first and second locations beside each other on the trailer and a third position where a third hay bale is unloaded on top of two hay bales in the first and second locations.
In further embodiments, the guide track includes a ramp for rotating the cradle for unloading a hay bale from the first position, the main track includes a one-way stop for preventing inboard movement of the main track wheel within the main track when unloading a hay bale from the second position and/or the main pivot arm includes a latch for locking the main pivot arm in a lower position when unloading a hay bale from the first and second positions.
In a further embodiment, the latch is operable to an unlocked position enabling the main pivot arm to upwardly pivot for unloading a hay bale from the third position.
In one embodiment, the hydraulic system includes a main hydraulic cylinder and piston and an auxiliary hydraulic cylinder and piston for supporting the main hydraulic cylinder and piston.
In another embodiment, the cradle includes a cradle extension system for adjusting the size of the cradle.
In yet another embodiment, the system includes a first treadle operatively connected to the trailer, the first treadle including an operative connection between the first treadle and one-way stop wherein actuation of the first treadle activates the one-way stop. In another embodiment, the system includes a second treadle operatively connected to the trailer, the second treadle including an operative connection between the second treadle and latch wherein actuation of the second treadle disengages the latch.
Further still, the system may include a conveyor belt system for operative connection to the trailer for moving tiers of hay bales rearwardly on the trailer.
BRIEF DESCRIPTION OF THE FIGURES
The invention is described with reference to the accompanying figures in which:
FIG. 1 is a schematic plan view of a hay bale stacking system and trailer in accordance with the invention.
FIG. 2 is a schematic end view of the hay bale stacking system in accordance with the invention showing picking up a first bale in a series of three.
FIGS. 3 , 4 and 5 are schematic end views of the hay bale stacking system in accordance with the invention showing the unloading of the first bale.
FIG. 6 is a schematic end view of the hay bale stacking system in accordance with the invention showing picking up a second bale in a series of three.
FIGS. 7 and 8 are schematic end views of the hay bale stacking system in accordance with the invention showing the unloading of the second bale.
FIG. 9 is a schematic end view of the hay bale stacking system in accordance with the invention showing picking up a third bale in a series of three.
FIGS. 10 and 11 are schematic end views of the hay bale stacking system in accordance with the invention showing the unloading of the third bale.
FIG. 12 is a schematic plan view of the hay bale stacking system showing linkage connections between a first treadle and stop and second treadle and latch in accordance with the invention.
DETAILED DESCRIPTION
System Overview
In accordance with the invention and with reference to the figures a hay bale collection and stacking system 10 is mounted on a flat bed trailer 30 . The system generally includes cradle 12 , pivot arm 14 , main track 15 , guide track 15 a , latch 14 b , one-way stop 26 and at least one hydraulic cylinder 18 mounted at the front end of the trailer 30 . The trailer 30 includes wheels 34 and a trailer hitch 35 as known to those skilled in the art.
More specifically, and as shown schematically in FIGS. 1 and 2 , the cradle 12 includes a track pivot wheel 13 able to slide and pivot within main track 15 and a cradle pivot wheel 12 a able to roll along the guide track 15 a that collectively enables both horizontal and vertical translation of the cradle from an outboard position as shown in FIG. 2 and various inboard positions as will be described in greater detail below and shown in FIGS. 3-11 . As shown, a main hydraulic cylinder and piston 18 is operatively attached between the frame of the flat bed trailer 30 and the cradle 12 to cause cradle 12 motion along the main track 15 and guide track 15 a . An auxiliary hydraulic cylinder and piston 18 a is operatively connected between the frame of the flat bed trailer 30 and a support point 18 b to assist in the support of the main hydraulic cylinder and piston 18 during operation of the system.
Additionally, the cradle 12 will preferably include a cradle hydraulic cylinder 18 d (shown in FIG. 12 ) to effect lateral extension and retraction of the cradle extension arm 12 b and thereby enable opening and closing of cradle arms 12 c and 12 d . The retraction of the cradle extension arm 12 b allows for the adjustment of the cradle so as to accommodate hay bales of different sizes within the cradle and/or to enable adjustment of the cradle to help prevent damage to the hay bale and its wrapping material as will be explained in greater detail below.
Generally, during operation of the system, round hay bales 20 a are picked up from the ground and stacked on the trailer in sets or tiers of three bales with the first and second hay bales 20 , 21 forming a base and a third hay bale 22 being placed on top of the first and second hay bales. As shown in FIG. 1 , as each set or tier is completed, a conveyor belt system 32 will move each set or tier to a rearward position on the trailer as denoted by the arrow.
Loading the First Hay Bale
Referring to FIGS. 2-5 , to load the first hay bale 20 , the cradle extension arm 12 b is lowered to a loading position such that it extends laterally and generally horizontally from the flatbed trailer 30 slightly above ground level to allow the operator to move the trailer and lifting system towards individual hay bales in the field. As the operator approaches a first hay bale 20 , the cradle 12 is opened sufficiently wide to receive the first hay bale 20 between the two forwardly extending cradle arms 12 c , 12 d of the cradle 12 by activation of hydraulic cylinder 12 d ( FIG. 12 ). Once the operator is satisfied that the cradle 12 and cradle arms are aligned with the first hay bale 20 , the operator drives the tractor 28 forward until the first hay bale 20 is engaged by the cradle 12 from behind and is contained within the cradle arms. The cradle extension arm 12 b may be adjusted laterally as necessary to ensure that the hay bale is properly positioned within the cradle arms.
When the first hay bale 20 is secure within the cradle 12 , the main hydraulic cylinder 18 is activated causing a rotation of the cradle 12 (containing hay bale 20 ) towards the flatbed trailer 30 as cradle extension member 12 e is drawn inwardly. Initially, inboard movement of the track pivot wheel 13 is prevented by the position of the cradle pivot wheel 12 a at the outer edge of the pivot arm 14 such that actuation of the main hydraulic cylinder 18 will cause the cradle pivot wheel 12 a to upwardly rise along the guide track 15 a thereby causing an initial vertical translation and rotation of the cradle 12 so as to lift the hay bale 20 above the deck of the flatbed trailer 30 . As the cradle pivot wheel slides along the guide track 15 a to the horizontal position, track pivot wheel 13 will then begin to move inwardly along main track 15 . Auxiliary hydraulic cylinder 18 a may support the main hydraulic cylinder 18 at this time.
Now referring to FIG. 3 , once the cradle pivot wheel 12 a has been lifted to the upper surface of the main track 15 , the cradle pivot wheel 12 a and track pivot wheel 13 will then be horizontally translated along the guide track 15 a and main track 15 respectively in the direction of ramp 24 . When the ramp 24 is reached, the cradle pivot wheel 12 a will engage with the ramp simultaneously causing further rotation of the cradle 12 about the cradle pivot wheel and upward movement of the cradle along the ramp 24 . At the same time, track pivot wheel 13 will reach the end of main track 15 . At the apex of the ramp, hay bale 20 is overcome by the force of gravity ( FIG. 4 ) and rolls out the cradle 12 . The first hay bale 20 comes to a stop on the flat bed trailer ( FIG. 5 ). Railing 31 is provided to prevent the first hay bale 20 from rolling off the trailer. As shown in FIG. 5 , hay bay 20 depresses first treadle 60 on the trailer which activates one-way stop 26 on the main track 15 .
The cradle 12 is then returned to the initial loading position by extending the hydraulic cylinder 18 which causes the translation of the track pivot wheel 13 along main track 15 and cradle pivot wheel 12 a along guide track 15 a respectively until the original horizontal or loading position is reached. The system 10 is then able to load the second and third hay bales 21 , 22 .
Loading the Second Hay Bale
The second hay bale 21 is collected and lifted from the field in the manner described above. As shown in FIGS. 6 and 7 , with one-way stop 26 engaged, as the hydraulic cylinder is activated, inward movement of the track pivot wheel 13 is prevented whilst still enabling upward and inward movement of the cradle pivot wheel 12 a . As a result, movement of the main hydraulic cylinder causes the cradle to rotate ( FIG. 7 ) and the second hay bale to roll onto the trailer ( FIG. 8 ). The second hay bale will then depress a second treadle 61 which causes latch 15 b to disengage.
The cradle is then returned to the loading position as described above.
Loading the Third Bale
A third bale 22 is then loaded within the cradle 12 as described above for the first two bales.
As shown in FIGS. 9-11 , with latch 15 b having been released and one-way stop still engaged, activation of the main hydraulic cylinder will cause the cradle to rotate upwardly as described above for the second bale 21 . Continued actuation of main hydraulic cylinder and actuation of auxiliary hydraulic cylinder 18 a will then cause the main pivot arm 14 to rotate upwardly about pivot 14 a until the third hay bale 22 rolls from the cradle 12 onto bales 20 , 21 .
Loading Subsequent Tiers
In a preferred embodiment, the flat bed trailer 30 as shown in FIG. 1 is equipped with at least one conveyor belt 32 . When three hay bales 20 , 21 , 22 have been stacked as shown in FIGS. 1 and 11 , the conveyor belt(s) 32 move the set or tier of hay bales at a minimum the horizontal length of one hay bale towards the rear of the trailer 30 . Sufficient space is now available to stack another three hay bales in a tiered configuration. This process may then be repeated until the flat bed trailer 30 is full.
Unloading the Flat Bed Trailer
A loaded trailer is then driven to a desired unloading location whereby the hay bales can be removed from the back-end of the trailer by continued activation of the conveyor belts 32 . In one embodiment, the back end of the trailer may be lowered to minimize the drop at the end of the trailer and to thereby allow the hay bales to be unloaded smoothly without falling off the rear of the flatbed trailer 30 in order to minimize the risk of damage to the hay bale or wrapping material if any.
System Control
The system is controlled by appropriate control systems to allow the retraction and extension of the hydraulics and the activation and deactivation of the one-way stop and latch as known to those skilled in the art. In particular, each of the main and auxiliary cylinders may be configured such that a single control allows for synchronized operation of the hydraulic systems while loading all three hay bales.
For example, as shown in FIG. 12 , appropriate cables 60 a , 61 a may be interconnected between treadles 60 , 61 and one-way stop 26 and latch 15 b , respectively. In addition, appropriate switches may be incorporated at appropriate locations on the system so as to prevent movement of components past the normal ranges of motion.
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. | The present invention relates to an improved system for collecting and stacking round hay bales on a flat bed trailer, particularly for use in agricultural applications such as farming or the like. | 0 |
RELATED APPLICATIONS
This application is a continuation-in-part of Ser. No. 488,789, filed July 15, 1974, and entitled "Multilayer Semiconductor Switching Devices".
FIELD OF THE INVENTION
This invention relates to semiconductor switches and more particularly relates to shorting structure for multilayer semiconductor switching devices.
THE PRIOR ART
A symmetrical switch for providing bidirectional switching is commonly termed a triac and has heretofore generally comprised five layers of alternating semiconductor types. Four of the layers have been utilized for switching or conducting during one-half cycle of an A.C. voltage source, and three of these same layers and a fifth layer are used for conducting during the alternate half cycle of the voltage source. Descriptions of the construction and operation of such five layer triac devices may be found in U.S. Pat. No. 3,275,909, issued Sept. 27, 1966 to F. W. Gutzwiller and U.S. Pat. No. 3,317,746, issued May 2, 1967 and U.S. Pat. No. 3,475,666, issued Oct. 28, 1969 to the present applicant.
Improved multilayer symmetrical semiconductor switches have been heretofore described in co-pending patent application Ser. No. 488,789, filed July 15, 1974, and entitled "Multilayer Semiconductor Switching Devices". The preferred embodiment of these improved switching devices has included at least seven layers of alternating types of semiconductor material to form a three terminal semiconductor switch which provides operating characteristics somewhat similar to prior triacs. However, such improved seven layer switches have improved voltage capacity and improved commutating and static dv/dt characteristics over conventional triac devices. With such improved multilayer switching devices, it is desirable to provide shorting between intermediate layers and external highly doped layers in order to provide improved switching operation. The present invention describes various techniques for providing such shorting structure.
SUMMARY OF THE INVENTION
In accordance with the present invention, a semiconductor switch includes a body having a plurality of layers of alternating first and second types of semiconductor material. A pair of regions of the first type of semiconductor material is formed on an outer surface of the body and is spaced apart by a pair of regions of the second type of semiconductor material. Electrodes contact the regions to form a gate and an anode. Structure is provided to electrically connect at least one of the regions with one of the intermediate layers which is interior within the body and is not immediately adjacent the regions. In the preferred embodiment, such structure includes small dimensioned extensions of the intermediate layer which extend through the layer immediately adjacent the regions into contact with the regions.
In accordance with another aspect of the invention, a semiconductor switch includes a body formed from a plurality of alternating layers of first and second types of semiconductor material. A first one of the outer layers is comprised of the first type of semiconductor material. A first pair of highly doped regions of the first type of semiconductor material is formed on the first outer layer of the body. The first pair of regions is spaced apart by a second pair of highly doped regions of the second type of semiconductor material formed on the first outer layer. At least one extension of an intermediate layer of the second type of semiconductor material extends through the first outer layer to contact one of the pair of highly doped regions of the second type of semiconductor material. This structure improves the switching speed and static dv/dt and commutating capabilities of the switch.
In accordance with another aspect of the invention, a semiconductor switch includes a body formed from at least five layers of alternating first and second types of semiconductor material. The body has first and second outer layers of the first conductivity material. A pair of regions of the first type of semiconductor material is formed on the first outer layer and is spaced apart by a pair of regions of the second type of semiconductor material. A region of the first type of semiconductor material is formed adjacent a region of the second type of semiconductor material on the second outer layer. Electrodes contact the regions to form a three terminal switching device. Extensions of the second type of semiconductor material extend from interior layers of the second type of semiconductor material through the first and second outer layers into contact with the regions.
DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention and for further objects and advantages thereof, reference is now made to the following description taken in conjunction with the accompanying Drawings, in which:
FIG. 1 is a top view of the preferred embodiment of the invention illustrating a plurality of shorting columns formed within the device;
FIG. 2 is a cross-sectional view of FIG. 1 taken generally along the section lines 2--2;
FIG. 3 is a sectional view of another embodiment of the invention;
FIG. 4 is a sectional view of yet another embodiment of the invention; and
FIG. 5 is a sectional view of yet another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2, a semiconductor body 10 may be seen to comprise a center layer 12 of N-type conductivity semiconductor material. P-type layers 14 and 16 are disposed on either side of layer 12. Outer layers 18 and 20 are formed of N-type material. It may thus be seen that body 10 comprises five layers of alternating types of semiconductor material. A pair of P+ regions 22 and 24 is formed on the exterior surface of the N-type layer 18. Regions 22 and 24 are spaced apart by regions 26 and 28 which are formed from N+ type semiconductor material. An N+ region 30 and a P+ region 32 are formed on the exterior surface of the outer layer 20. The body 10 may thus be termed a seven layer semiconductor device.
An electrode 34 contacts P+ region 22 and N+ region 28 to form a gate electrode. An electrode 36, which may comprise a ring electrode, contacts the N+ region 26 and the P+ region 24 to form a first anode terminal. An electrode 38 contacts the N+ region 30 and the P+ region 32 to form a second anode terminal.
An important aspect of the present invention is that small dimensioned extensions 40 of P-type material extend from the P layer 14 through the N-type layer 18 into contact with regions 22, 24, 26 and 28. As shown in FIG. 1, the extensions 40 in the preferred embodiment have a generally circular cross-section and have dimensions substantially less than the width of the body 10. Although the extensions 40 are illustrated in FIG. 1 as being symmetrically located across the entire surface of the body 10, it will be understood that the extensions may be randomly or irregularly spaced across the body 10. Similarly, extensions 42 extend from the P layer 16 through the N layer 20 into contact with the regions 30 and 32.
Upon inspection of FIG. 2, it will be seen that the extensions 40 provide conductive paths from the interior P-type layer 14 to the P+ regions 22 and 24. The extensions 40 are essentially terminated by the N+ regions 26 and 28. The extensions 40 thus provide shorting contact with the interior P-type layer 14 and electrodes 34 and 36 in order to provide substantially improved switching times for the device. Similarly, extensions 42 cause shorting between the interior layer 16 and the P+ region 32 and electrode 38. The shorting configurations substantially improve the commutating capability and provides much greater static dv/dt to the device. For example, a static dv/dt in excess of 1,000 volts/microsecond may be provided by the present device.
Operation of the device shown in FIGS. 1 and 2 is described in greater detail in the co-pending patent application Ser. No. 488,789. Generally, the device operates in a somewhat similar manner as a triac as far as the application of external control and gating voltages thereto, but the interior operation is substantially different. The present device includes more interior blocking junctions than are found in conventional triac devices, and thus provides substantially improved voltage capacity and other operating characteristics. An analogy of the operation of the present device is that of a conventional four layer SCR in series with a saturated NPN transistor.
The semiconductor body shown in FIGS. 1 and 2 may be formed in any suitable manner according to techniques well known in the art. For example, an N-type electrical conductivity silicon wafer may be diffused on both sides in various steps to form the five layers 12, 14, 16, 18 and 20, along with the extensions 40 and 42. The P+ and N+ regions 22-28 may be then formed in the outer portions of layer 18 by conventional diffusion techniques using suitable dopants or impurities which are compatible with the particular semiconductor material being operated upon. The regions 30 and 32 may be diffused into layer 20 in a similar manner.
The particular size and shapes of the diffused regions are, of course, determined by suitable masking and photographic techniques conventionally employed in semiconductor diffusion technology. It will be understood that any suitable semiconductor material may be utilized to form devices according to the invention, but for clarity of illustration, reference is made in the drawings to particular electrical conductivity types and to silicon as the material being utilized. It will, of course, be understood that the electrical conductivity types herein specified may be interchanged and reversed.
The present invention provides extremely good temperature characteristics. Inasmuch as most of the temperature stability of the device is controlled by the outer NPN regions of the device, the emitter efficiency of the N emitter of the device is made relatively low to provide low Beta characteristics at low current levels. The N+ regions of the device are provided to provide improved forward voltage characteristics. At low current levels, the lightly doped intermediate N-type layer appears as the emitter and the resulting Beta of the device is relatively low, thereby providing good temperature stability characteristics. At high current levels of the device, the N+ region operates as the emitter to provide good on voltage characteristics.
The device shown in FIGS. 1 and 2 in the preferred embodiment have been provided with a total thickness of approximately 8 to 12 mils, which is thicker than conventional five layer triac devices. The present devices have been found to gate at relatively low gating currents in all four quadrants. This phenomena is thought to occur due to the fact that no transverse switching currents are required for operation of the present device.
FIG. 3 illustrates another embodiment of the present invention, with like numerals being utilized for like and corresponding parts previously described. In the embodiment shown in FIG. 3, a groove 50 is disposed between regions 22 and 28 and extend through the N-type layer 18 into the P-type layer 14. Groove 50 thus geometrically and electrically isolates the P+ region 22 and the N+ region 26 from N+ region 28 and P+ region 24. Groove 50 extends linearly completely across the body 10 of the device. Similarly, a groove 52 extends through the lower face of the body 10 and separates the P+ region 32 from the N+ region 30. Groove 52 extends through the N-type layer 20 into the P-type layer 16.
In the embodiment shown in FIG. 3, only a single extension 40 is shown which extends from the P-type layer 14 through the N-type layer 18 into contact with the P+ region 24. Extension 40 thus provides shorting contact between the interior P-type layer 14 and the exterior P+ region 24. Similarly, a single extension 42 is illustrated as extending from the interior P-type region 16 through the N-type layer 20 into contact with the P+ region 32. Extensions 40 and 42 operate to provide improved switching characteristics in the manner previously described.
An electrode 54 contacts the N+ region 26, while an electrode 56 contacts the P+ region 24. Similarly, an electrode 58 contacts the P+ region 22 while an electrode 60 contacts the N+ region 28. An electrode 62 contacts the P+ region 32, while an electrode 64 contacts the N+ region 30. The electrodes of the embodiment shown in FIG. 3 may be interconnected in the manner shown in FIG. 2 to provide a three terminal symmetrical switch. Alternatively, the electrodes illustrated in FIG. 3 may be interconnected in various other ways to accomplish different types of switching.
While the grooves 50 and 52 are illustrated as being linear in FIG. 3, it will be understood that the grooves may be provided with different configurations in order to improve switching in the various quadrants of the device. The grooves may thus be provided with the configurations illustrated in co-pending patent application Ser. No. 522,603, filed Nov. 11, 1974, by applicant and entitled "Four Quadrant Symmetrical Semiconductor Switch".
FIG. 4 illustrates a device generally similar to FIG. 2, with the exception that extensions 40 and 42 have been replaced by bonded electrical wires 70 and 72. In this manner, conductive paths are formed between the interior P layer 14 and the exterior P+ region 24. Similarly, conductive paths are provided between the interior P-type layer 16 and the exterior P+ region 32. Although single wires 70 and 72 are illustrated, it will be understood that a plurality of such wires may be connected about the periphery of the device. Similarly, other conductive paths such as metalization strips may be formed to accomplish the invention.
FIG. 5 illustrates yet another embodiment of the present invention wherein like numerals are utilized for like and corresponding parts. In this embodiment, a groove 80 is formed through the P+ region 24 and extends through layer 18 into the P-type layer 14. A conductive metal layer 82 is formed in the groove in order to provide a conductive path between the interior P layer 14 and the exterior P+ region 24. Similarly, a groove 84 is formed through the P+ layer 32 and extends through the N-type layer 20 into the P-type layer 16. A layer of metalization 86 is formed on the groove 84 in order to provide a conductive path between the interior P-type layer 16 and the exterior P+ region 32. This conductive path provides the advantages of operation previously noted.
Whereas the present invention has been described with respect to specific embodiments thereof, it will be understood that various changes and modifications will be suggested to one skilled in the art, and it is intended to encompass such changes and modifications as fall within the scope of the appended claims. | The specification discloses a semiconductor switch having a body formed from at least five layers of alternating first and second types of semiconductor material. A pair of regions of the first type of semiconductor material are formed on an outer surface of the body and are spaced apart by a pair of regions of the second type of semiconductor material. Electrodes contact the regions and form a gate and an anode. An electrode contacts the other outer surface of the body to form a second anode. Structure is provided for electrically connecting at least one of the regions with an intermediate layer which is interior within the body and is not immediately adjacent the regions. This shorting structure increases the switching speed of the device and improves the commutating and static dv/dt capabilities of the device. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to the compensation of time errors in a television signal, particularly a recorded signal.
A television signal coming from a recording instrument, e.g. on a magnetic tape or video record, is known to be subject to time errors resulting from fluctuations in speed or changes in the shape of the record carrier. Often the magnitude of these speed fluctuations or shape changes varies cyclically, causing the time error to vary in magnitude cyclically, at some frequency.
It is known to compensate such time errors by including an electronically controllable delay line in the signal path, as disclosed, for example, in German Pat. No. 1,014,153. A phase comparison of the line sync pulses separated from the faulty signal with constant line sync pulses or a comparison of an additionally recorded pilot carrier with a constant pilot carrier (e.g. 600 kHz) produces a setting value which represents the time error and which changes the delay time in the delay line on the basis of a fixed basic delay time to compensate the time error. If, for example, the line scanning period of the signal is too short, the delay time is increased and the signal is expanded relative to the time axis to the correct value of the line scanning period.
For such a circuit it is also known, as disclosed in German Offenlegungsschrift No. 2,122,592, and U.S. Pat. No. 3,863,022 based on application Ser. No. 251,229 filed by Walter Bruch on May 8th, 1972, to employ, as the controllable delay line, an electronic memory, such as a bucket cascade device, which is timed by clock pulses, and to influence the frequency of the clock pulses by the setting value.
It has now been found that when the above-described time errors occurring in the signal vary cyclically in amplitude at certain frequencies such a circuit does not achieve sufficient time error compensation. It was noted that the signal became even poorer when the frequency of the time error variations increased. This drawback could not be overcome by increasing the amplification of the setting value since then the errors would be overcompensated at other time error variation frequencies.
SUMMARY OF THE INVENTION
It is an object of the present invention to further improve the known circuit for compensating time errors so that the circuit operates dependably over a wider time error frequency range.
These and other objects are achieved according to the present invention, in a circuit for compensating time errors in a television signal and including an electronically controllable delay line in the path of the signal, and control signal producing means for producing a control signal to vary the delay time of the delay line, by the provision of delay means connected to cause the delay time of the control signal path to be adapted to the basic delay time of the delay line.
The present invention is based on the following: the delay line disposed in the path of the useful signal has a certain basic delay time. This basic delay time of, for example, 20 μs is necessary so that the setting value will be able to change the delay time in a positive as well as a negative direction. On the other hand, a delay is also present in the path of the setting value, i.e. the setting value appears at the control input of the delay line only a certain period after the occurrence of the error in the signal.
A significant improvement in the efficiency of the circuit can now be obtained if, according to the present invention, these two delays are adapted to one another, preferably so that the delay effective in the path of the setting value is approximately equal to one-half the basic delay time of the delay line in the path of the signal. In this case the setting value becomes effective at the control input of the delay line at the optimum point in time and a better time error compensation is realized.
If no significant time delay is present in the path of the setting value, an additional delay is added in this path. If the delay in the path of the setting value is already greater than the basic delay time of the delay line in the signal path, an additional delay is provided in the signal path, i.e. in series with the delay line.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a circuit diagram of one preferred embodiment of the invention.
FIG. 2 is a circuit diagram of one embodiment of the generator 11 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the circuit shown in FIG. 1, a video signal 2 containing line sync pulses 9 and exhibiting time errors is present at terminal 1. Signal 2 passes through an electronically timed memory 3 which serves as the controllable delay line and which has a basic delay time υ O given by the frequency of the controlling clock pulses 12. The frequency of the clock pulses 12 is controlled in dependence on the time error so the delay time is changed by ±Δυ to produce a time error compensation. At a terminal 4 there then appears a video signal 2' which does not contain any time errors.
In a separator stage 5 the line sync pulses 9 are separated from the video signal 2 and fed to a phase comparison stage 6 in which the line sync pulses are compared with pulses from a generator 7. The resulting setting value U s is applied via a filter member 8 to adjust the output from generator 7 to the center frequency of the line sync pulses 9. The setting value U s at the output of stage 6, i.e. before filter member 8, follows the time fluctuations of the line sync pulses 9 and thus constitutes a representation of the time error in signal 2.
This setting value passes through a bandpass filter 10 to a generator 11, which produces the clock pulses 12 for memory 3. If, for example, the line scanning period for signal 2 is too short, the frequency of the clock pulses 12 is reduced. Then the signal 2 passes through memory 3 more slowly so that the line scanning period is expanded to the proper value. The circuit described thus far is known.
According to one embodiment of the present invention, a delay member 13 is included in the path of the setting value U s This delay member 13 produces a delay such that, together with the delay time of the filter 10 in the path of the setting value, it produces a delay of one-half the basic delay time of memory 3, i.e. υ O /2. In this case it is assumed that no other delay is present in the path of the setting value, i.e. in the path constituted by elements 5, 6, 14, 11. The delay member 13 thus makes the delay period in the path of the setting value equal to υ O /2.
This has the result of causing a change in the frequency of the clock pulses 12 resulting from a time error to become effective at the control input of the delay line at the proper point in time. The delay member 13 can also be placed somewhere else in the path of the setting value, e.g. before or after the separating stage 5.
The signal at the input of memory 3 is the original undelayed signal 2 whereas the signal at the output of memory 3 is delayed by υ o . By this reason it gives optimal results if the time correction occurs at a moment in the middle between no delay and delay of 98 o , i.e. at a moment υ o /2 later than the original signal. This can also be shown by a methematical calculation.
If it is found that the delay time already present in the path of the setting value is greater than υ O /2, an additional delay member 13' can be included in the path of the signal, in which case the direct connection between terminal 1 and delay member 3 would be interrupted.
A further improvement in the time error compensation is obtained when the amplitude of the setting value is influenced in dependence on the rate of change of the setting value, and thus also in dependence on the rate of variation of the time error, according to the factor ##EQU1## where ω represents the rate of change of the setting value in radians/sec. and thus also of the rate of variation of the time error, and υ O is the above-described basic delay time.
In FIG. 1 this frequency dependent amplitude distortion is effected by an equalizer 14. With an amplitude distortion according to the above formula it is theoretically possible to obtain an almost complete error compensation in the entire frequency range of interest of the time errors. For very small values of ωυ O the individual solutions provided blend into one another. Circuits for frequency dependent amplitude distortion according to a special function as performed by equalizer 14 are described in the book "Reference data for Radio Engineers, fourth edition, International Telephone and Telegraph Corporation, 1956".
In order to produce a time error compensation, the frequency of the clock pulses 12 deviates from a basic frequency f o by a variable component Δf. The delay time produced by memory 3 is proportional to the period duration of the clock pulses 12. This delay period is supposed to change in correspondence with the time error.
In an advantageous manner, the circuit is thus dimensioned so that the variable component Δ(1/f) of the reciprocal of the frequency of clock pulse 12 is proportional to the time error. This can be accomplished by an additional amplitude distortion of setting value U s or generator 11 may be designed so that the magnitude of the variable portion of the reciprocal of the frequency of the clock pulses generated by generator 11 is directly proportional to the applied setting value. In this case it is assumed that the setting value itself is proportional to the time error.
A generator with said properties can be realized by a multivibrator with two transistors if the operating voltage for the collector-emitter paths of the transistors is varied linearly with the setting value. E.g. the sum of a constant operating voltage and of said setting value may be applied as dc-operating voltage to the collectors of both transistors.
FIG. 2 illustrates one embodiment of a generator 11 having an operating characteristic which produces the above-described relationship. The generator shown in FIG. 2 is essentially a multivibrator composed of two transistors 34 and 35, two collector resistors 36 and 37, two coupling capacitors 38 and 39, and base resistors 20 and 21. The generator produces the train of clock pulses 12 at its output terminal 22. In known circuits, the setting value U s would be applied via terminal 24 to the bases of transistors 34 and 35. This would establish a linear relationship between the frequency f of the clock pulse sequence 12 and the setting value U s , and thus also a linear relationship between the frequency f and the time error.
However, in the circuit shown in FIG. 2, the setting value U s is not applied to terminal 24 but rather is applied to terminal 23, together with the operating voltage U 1 . From terminal 23, the combined voltage is supplied to the collectors of transistors 34 and 35. Terminal 24 is connected to a source of a fixed bias voltage U 2 . This bias voltage U 2 is given a value which is high with respect to the pulse amplitudes present at the bases of the transistors so that an almost constant current flows through resistors 20 and 21. This constant current, which is independent of the pulse voltages and which effects recharging of the capacitors 38 and 39, produces a time proportional recharging of capacitors 38 and 39, and thus establishes a linear relationship between 1/f and U s . It has been found that in this circuit, in which the setting value controls the collector voltage of transistors 34 and 35, there exists a linear relationship between the reciprocal 1/f of the frequency f of the train of clock pulses 12 and the setting value U s , and thus the time error.
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. | In a circuit for compensating time errors in a television signal and including an electronically controllable delay line in the path of the signal and control signal producing elements in a control signal path connected to the line to vary the delay from a basic value of υ O by ±ΔΥ, the delay time of the control signal path is given a value which has a selected relation to υ O . | 7 |
BACKGROUND OF THE INVENTION
The invention concerns an extrusion device for impregnating a rock formation, preferably for bonding with a liquid synthetic product, with the use of a piston pump having at least one working cylinder.
The invention is applicable, in particular, to underground excavation operations and to the impregnation of the rock or the mineral, respectively, in particular, overhanging coal. Preferably, the invention is used for stabilizing the formation by bonding teary strata with the aid of a diisocyanate and polyalcohol by using polyurethane foam compound consisting of these two components. Although the invention can, be applied for saturating the face of the coal with water, it is explained in detail in the following description of its application to the extrusion of the so-called standard compound for mining of the two component foam compounds mentioned above.
For this application of the invention a working cylinder must be provided for each of the two components, because the two liquid components may only be combined in a bore hole. For this type of piston pump a working cylinder may be provided. Occasionally it is practicable to align a driving cylinder with each working cylinder so as to apply the propulsive force more advantageously to the driving piston. On the one hand, the control of the driving cylinder must insure that the driving pistons are operated with the force required to operate the working piston. On the other hand, the control must insure a timely reversal at the end of each cycle and that the energy contained in the working fluid is converted most effectively into pump energy.
According to the prior published state of the art (magazine Gluckauf 113 (1977), 707, 711), a gear pump is driven by a pneumatic motor. It has the disadvantage that compressed air is not always available in the needed amount and at favorable energy cost and, further, the gear pump must be able to handle component extrusion fluids of different viscosities, as is the rule with the above mentioned standard compound for mining. Differences in viscosity between the two extrusion fluids makes adherence to the specified ratio of the liquid components practically impossible, primarily because of the unavoidable loss by leakage, thereby resulting in reduced efficiency.
SUMMARY OF THE INVENTION
These disadvantages are overcome by the invention described herein. A device has already been suggested, which, instead of a geared pump, provides for each component a working cylinder and for each working cylinder a hydraulically operated driving cylinder. Piston pumps avoid the clearance losses experienced with geared pumps, because piston pumps operate with sealed pistons. It is relatively easy to control them so that the unintended blending of the two components in a working space is prevented. Further, the required high operating pressure can be applied without significant energy losses. As a rule, the hydraulic drive is superior to the pneumatic drive as the extrusion system can be operated with any type of energy source, and for this reason neither the availability of a specific type of energy nor its power limitation is a deterring factor.
The invention has its primary objective to design the extrusion device which overcomes the shortcomings of the previously published state of the art so that it can be operated with a high degree of utilization of the energy source applied, and in particular, that it can be operated with extremely high operating forces of the hydraulic medium which is conveniently available onsite for other purposes, e.g., for operating the rams or for the hydraulic roadway and/or face-supports.
This problem is solved according to the invention by the distinguishing characteristics of the patent claims.
By providing a control spindle for regulating the working valves which control the inflow and outflow from the pressure chambers of the working cylinder, any number of valves can be operated in precisely timed synchronization, which is a prerequisite for the application of high pressures of the operating medium. Operating the control spindle with the operating fluid has the added advantage of being able to reverse the control spindle instantly because of the high propulsive force. This is accomplished when the appropriate signal is triggered at the end of the path of the piston travel in the driving cylinder. By using the driving piston for opening the valves controlling the pressure chambers of the driving cylinders, the reversal of the driving piston can be carried out automatically, i.e. in the respective end position of the driving piston, while at the same time avoiding, through the reversing lag of the valves effecting the pressure chambers of the control spindle, that these are closed too suddenly due to the high pressure of the hydraulic fluid.
The invention therefore has the advantage that the driving cylinders can be operated via a valve control which, as opposed to a slide-valve gear, prevents fluid loss and is therefore particularly well suited for high hydraulic fluid pressure applications. These pressures may be in the range of 150 bar, as are used underground for operating the step and ram cylinders; also driving forces of up to 300 bar can be considered, as are associated with the hydraulic mine props, such as for shaft shields. These are in particular, pressure water or pressure emulsions which are used underground because of their incombustible nature, but which also have lubricating characteristics.
Preferably the cylinder chambers are continuously loaded with the hydraulic fluid via a throttle, and the discharge is directed via one of the control valves, the outflow of which is chosen to be greater than the inflow via the throttle. This then means that the pressure chamber, the control valve of which is closed, governs the actuation of the control spindle, but excessive mechanical stresses cannot arise.
The control is preferably constructed as a spindle, the ends of which move into the control pressure chambers as pistons. Between the ends of the spindle is a plurality of ramps, cylindrical portions or sections whereupon the driving valve rollers travel thereby controlling the two pressure chambers of the driving cylinder.
The invention is applicable in particular in combination with valve controlled working cylinders. This type of working cylinder accommodates the considerable extrusion pressures and avoids the disadvantages of a slide-valve gear under high pressure. According to the invention, the working cylinder is equipped with a hollow piston for the suction or intake stroke and for the delivery or ejection stroke with a concentric piston rod located within the hollow cylinder. It is possible to operate intake and delivery via only one opening in the working cylinder, in which case only the final delivery opening has to be provided with a check valve.
BRIEF DESCRIPTION OF THE DRAWINGS
The details, additional characteristics and other advantages of the invention can be seen in the following description of an embodiment with the aid of the figures in the drawing which show:
FIG. 1 is a side view, in partial section, of a two cylinder piston pump according to the invention;
FIG. 2 is a front view of the embodiment shown in FIG. 1;
FIG. 3 is a plan view of the two cylinder pump of FIG. 1 with the tank shown in phantom line to more clearly display the components located underneath the tank;
FIG. 4 shows the control valve arrangement for the driving cylinder with the driving piston at rest at the center of its travel;
FIG. 5 shows the control valve arrangement according to FIG. 4 with the driving piston moving in the direction indicated by the arrow;
FIG. 6 shows the position of the control valve arrangement according to FIGS. 4 and 5 with the driving piston moving in the opposite direction from that of FIG. 5;
FIG. 7 shows the control valve arrangement according to FIGS. 4 to 6 during reversal of the driving piston;
FIG. 8 shows a partial cross-section of a housing including the important components of the hydraulic control;
FIG. 9 shows a front view of the housing of FIG. 8; and
FIG. 10 is a side view of the housing of FIG. 8.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 through 3 show the basic construction of the extrusion device according to the invention. The extrusion compound consists of two components, which flow from the tank 1 via either the elbow 2 or 2' into one of the two working cylinders 3 or 4, respectively. The delivery lines to the cylinders 3, 4 are provided with a hydraulic connection at 5 and 6. The two working cylinders 3, 4 are operated in the same cycle, so that the different components from the tank 1 and the working cylinders 3, 4 are drawn in simultaneously and discharged simultaneously with the next cycle by the working cylinders at the hydraulic connections 5, 6. Not shown is the subsequent delivery line, where the components are finally combined.
Instead of a two component compound, the embodiment described consisting of the working cylinders 3, 4 may also be utilized to pressurize water or similar liquids.
A tubular frame consists of two side rails 7, 8 which protect the operating parts and its driving member. The side rails are generally rectangular and are installed parallel to each other. They support the tank 1 for the extrusion liquid, which is connected to the working spaces of the cylinders via the plug-in disconnect mountings at the elbows 2 and 2'.
The working cylinders 3, 4 and the parts associated with each cylinder are constructed identically. A cylinder barrel 9 has at its delivery line end a vacuum connection or inlet 10 and is closed with a bushing 11, which is screwed into the face of the housing 12 of a one way check valve. The one-way check valve is equipped with a ball valve 14 and a spring 15. The seat of the ball is shown in FIG. 1 at 13. The check valve is installed so that it automatically closes the delivery line 5, 6 when the respective pump cylinder inducts the cylinder contents via the vacuum line connection 10.
The suction cycle is executed with a hollow piston 16, which is coaxially mounted on a piston rod 17, which on its part is sealed at 18 against the inside of the hollow piston 16.
For the suction stroke, both the hollow piston 16 and the piston rod 17 are moved to the left as viewed in the drawing in FIG. 1, whereupon the check valve closes and the fluid compound enters the cylinder via the elbow 2 through the inlet 10 into the cylinder barrel 9. During this process both the hollow piston 16 and the piston rod 17 lift off the bushing 11 until the hollow piston 16 abuts a bushing 20 located at the opposite end of the piston cylinder. This clears the way for the fluid compound to be introduced into the hollow piston 16 along its end face. During the further movement of the piston rod 17 the hollow piston 16 remains stationary and the fluid compound is drawn in via the inlet 10 until the piston rod 17 has reached the end position of its suction stroke. After reversing, the piston rod 17 begins the compression stroke and moves to the right as viewed in the drawing in FIG. 1. The hollow piston 16 travels along with the piston rod until the hollow piston end face seals with its front end 21 on its associated seat 22 of the check valve. Therefore the drawn-in fluid compound cannot flow back via the inlet or vacuum connection 10. The ball of the check valve 14 is pushed by the continued movement of the piston rod 17 against the force of the spring 15, whereby the drawn-in fluid compound is pushed into the subsequent delivery line (not shown) via the respective hydraulic connection 5, 6.
As the pump operates without a suction valve, even compounds of high viscosity can be handled without suction problems.
As shown in FIG. 3, the piston rod ends 24, 25 extending beyond the bushings 20 are attached to a common yoke 26. The cylinders are mounted on a crossbar 27 of the tubular frame. The crossbar 27 further supports two fixed pipes 28, 29 mounted in each of which is a rod 30 with a similar fixed yoke 31 as the fixed yoke 26. The yoke 31 supports a bushing 34 with a wiper 35, as best illustrated in FIG. 1, for a piston rod 33 of a drive unit. The piston rod 33 is connected to the yoke 26 so that it extends equidistant from the central axis of the piston rods 17 of each of the two working cylinders 3, 4.
Also attached to the yoke 31 is a bushing 36 which encloses one end of the driving cylinder 37, the other end of which is likewise enclosed with a bushing 38. The bushing 38 is attached to a crossyoke 39, which holds the two side rails 7, 8 of the tubular frame together with a screw-coupling 40, 41. The bushing 38 has a wiper design 42 for the other end 43 of the piston rod 33. Mounted on this other end 43 of the piston rod is a shelf 44, on which a pad 46 is mounted, which in turn supports a tappet 47 with a tappet spring 48 mounted parallel to the piston rod. A similar shelf 49 is mounted at the one end 50 of the piston rod 33, with a pad 51, supporting a tappet 52, which is also equipped with a spring 57. Both of the tappets 47 and 52 are adjustable via the adjustment screws 58, 59.
Mounted on the piston rod 33 is the driving piston 60 which divides the driving cylinder 37 into two independent pressure chambers 61, 62. The driving piston 60 has end faces of equal size for both pressure chambers 61 and 62. A control valve 63 for the driving cylinder 37 is located between the two side rails 7, 8 or the tubular frame, directly mounted to the driving cylinder 37.
For the alternating pressurizing of the pressure chambers 61, 62 of the driving cylinder 37 an automatic control valve is provided which is explained in detail with reference to FIGS. 4 through 7 as follows.
The two pressure chambers 61, 62 are connected via lines or connections A and B to the inlet and outlet of the pressure medium. They are placed under pressure or relieved of pressure through the driving valves 91, 93 or 92, 94 respectively. The driving valves are controlled by a spindle S, the ends of which form pistons 70, 71 housed in cylinders 72, 73, forming pressure chambers 74, 75. The spindle has cylindrical portions 76, 77 of identical diameter and a center section 78, as well as end sections each 79, 80 of larger diameter, whereby the outer diameter of the center and end sections 78, 79 and 80 are identical. Conical parts 81, 82, 83, 84 connect the cylindrical portions of different diameters and serve as ramps for the mechanical components 85, 86, 87, 88 of the two-way valves 91, 92, 93, 94. The control valve 63 operates according to the following description.
In the position in FIG. 4 all of the valves 91, 92, 93, 94, 95, 96 are closed. The flow of the pump P and the cylinder connections A and B are blocked. The spindle S is in its center position, and the driving piston 60 does not move in the driving cylinder 37.
To start the pump, the pump inlet must first be closed to relieve the pressure on the inlet side of the pump. The spindle S is then manually moved into either of its end positions, as shown in FIGS. 5 and 6, respectively. Thereafter the pump can start up. As soon as the pump flow is released, the pump begins to operate.
In the configuration of FIG. 5 the pressure chambers C and D of the spindle S are both supplied with the driving pressure from the pump. Therefore the position of the spindle S is fixed, as long as the valves 95, 96 are closed. The driving piston 60 and the piston 33 move to the left in the illustration in FIG. 5, which corresponds to the suction stroke of the piston rod 17. The movement occurs because the driving valves 92 and 93 have been opened due to the mechanical components 86 and 88 moving up their respective ramps and becoming influenced by the center section 78 and the end section 80, respectively. Therefore hydraulic fluid enters the driving cylinder 37 under the influence of the two-way valve 92 via connection B, and the driving piston 60 displaces fluid via connection A due to the two valve 93 into the return line.
The configuration of FIG. 6 shows the reverse position from that of FIG. 5, wherein the driving piston 60 and the piston 33 move in the opposite direction, corresponding to the ejection or delivery stroke of the piston rod 17.
FIG. 7 illustrates the position of the driving cylinder as it begins the suction stroke. The piston rod 33 has reached its mechanical end position, that is, the end of its delivery or injection stroke at this position, and the control valve 95 is opened by the tappet 47 via the tappet spring 48. Therefore the pressure in the chamber C is relieved, in that, more fluid escapes via the control valve 95 as can enter via a throttle 97. Since the control valve 96 remains closed, the spindle S is pressed towards the opposite end position by the inflow of hydraulic fluid in the chamber D via a throttle 98. Moving the spindle towards the chamber C closes the operating valves 91 and 94, while the operating valves 92 and 93 open, causing the piston rod 33 to move into the opposite direction.
Therefore, in each of the respective end positions of the piston rod 33 the opening of the control valves 95 and 96 causes automatic reversal. The driving cylinder operates otherwise via control by the valves.
The control valves 95 and 96 open as the springs 48 or 57, respectively, are compressed, the pressure within the valves decreases during the initial path of travel of the tappets 47, 52, which upon reversing cause the valves 95, 96 to close again. As a result, the movements of the spindle are initiated instantly, but are not sudden in spite of the high pressures exerted by the hydraulic fluid.
FIGS. 8 to 10 show an applied embodiment of a control, the action sequency of which has been described with the aid of FIGS. 4 to 7. Accordingly, the spindle S is located in a housing 100, which is closed on both its ends with end caps 101 or 102, respectively. The two caps are connected to one another by head bolts 103 or 104, respectively, acting as tie rods, and are pressed against the face of the housing. Nuts 106, with lock washers 107, are threaded onto the ends of the head bolts 103, 104. On each outer face 108 or 109 of the caps the tappets 110 or 111, respectively, of the control valves 95 or 96, respectively, protrude. These tappets are acctivated by the valve heads 112 (FIG. 1), which are mounted on the springs 48 or 57, of the tappets 47 or 52, respectively.
The control valves 95, 96 are constructed identically and have a valve ball 114 as a closing or throttling member, which is loaded with the force of a spring and can be lifted off its seat by the tappet 111.
The pressure chambers C and D are also contained in the end caps 101 or 102 respectively.
The driving valves 91, 92, 93, 94 are also constructed identical to the illustrated valve 95 and, like the control valves, are each provided with a ball 115 serving as a closing or throttling member. The valve tappet 116 of each driving valve 91, 92, 93, 94 carries on its free end a roller 117, which travels on the spindle. | The invention concerns an extrusion device for impregnating rock formations preferably for bonding with a liquid synthetic product, with the use of a piston pump having at least one working cylinder. During the induction or suction stroke a working piston is filled with the extrusion liquid or with one of its components, and is emptied during the delivery stroke cycle. The working piston is controlled by a pump drive equipped with at least one driving cylinder and a driving piston which can be pressurized on both sides of the piston sequentially. A control valve pressurizes the piston surface with a working fluid as the other working surface of the piston is relieved. The extrusion device, can operate with more efficient utilization of the energy source applied and in particular with extremely high operating pressure of the available hydraulic medium, which is already available but used for other purposes, i.e., the operation of the rams or the hydraulic face- and/or roadway supports. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
Not applicable.
STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
BACKGROUND OF THE INVENTION
This invention relates to sinks. In particular, this invention relates to utility sinks such as laundry sinks.
Although many clothes are laundered using modern washing machines and dryers, some types of fabrics still require hand washing. Although washtubs for hand washing fabrics were once commonplace, it is now rather rare for individuals to have a dedicated washtub. Thus, most hand washing, if not performed by a professional cleaner, is done using an available sink.
Typically, hand washing of clothes and other fabrics is performed by plugging the available sink, filling the sink with water of an appropriate temperature, adding cleaner, and allowing the fabrics to soak. After scrubbing the clothes, the sink is drained and the clothes are rinsed. The clothes may then be wrung out and hang dried.
However, it can be inconvenient to commit a sink to washing clothes and fabrics since this renders the sink temporarily inaccessible for other uses such as, for example, the washing of hands or other items. As many utility sinks are used for a variety of purposes, surface of the sink can become soiled. Particularly when these substances are oily or could stain the clothes, it may be undesirable to use an all-purpose sink for hand washing.
Hence, a need exists for improved means of hand washing fabrics. In particular, there is a need for a better way to hand wash fabrics that does not require the use of antiquated devices, such as washtubs.
SUMMARY OF THE INVENTION
The present invention provides a utility sink comprising a sink and a bucket. The sink has a basin extending from an upper edge to a drain. The bucket has walls extending to a lip and has at least one opening formed in a side portion of the walls. The lip is configured to selectively contact the upper edge of the basin such that the bucket is suspended in the basin. The at least one opening of the bucket, in addition to facilitating handling, provides a form of overflow when the bucket is suspended in the basin of the sink, such that the at least one opening places an interior volume of the bucket and the basin of the sink in communication with one another.
Additionally, the bucket may have a structure conducive to the openings performing as pour spouts. The side portion of the walls may extend from a base portion of the walls at a non-right angle. The at least one opening may be located on the walls proximate a radiused transition between the side portion of the walls and the lip. Thus, the at least one opening may located on a non-vertical plane that promotes pouring out of the handles at relatively low angle of tilt for the bucket.
Further, a portion of the lip may raises around the at least one opening in the bucket such that the at least one opening is accessible from between the sink and the bucket. In this way, the bucket may be removed or lifted from the sink in an ergonomic manner.
According to one aspect of the invention, when the bucket is suspended from the upper edge of the sink, the lip covers at least half of the upper edge. Additionally, a rack can be placed on a floor of the basin to cover the drain and may further support the bucket.
The present invention can further include a shallow tray having an outer rim that selectively mates with the lip of the bucket. The shallow tray can have at least one opening formed therein. When the shallow tray mates with the lip of the bucket, the at least one opening of the shallow tray can nest over the at least one openings of the bucket. The shallow tray may include a plurality of holes formed therein. The shallow tray may also include a central larger hole that facilitates the hanging of the shallow tray between uses.
According to another aspect of the invention a utility sink is provided comprising a sink, a rack, a bucket, and a shallow tray. The sink has a basin extending from an upper edge to a drain. The rack is placed on a floor of the basin such that the rack covers the drain. The bucket has walls extending to a lip and having at least one opening. A side portion of the walls is angled away from a base portion of the bucket. The at least one opening is located on the walls proximate a radiused transition between the side portion of the walls and the lip. Accordingly, the at least one opening is not located on a vertical plane. Further, a portion of the lip is raised around the at least one opening in the bucket. The shallow tray has an outer rim that selectively mates with the lip of the bucket. The at least one opening of the bucket, in addition to facilitating handling, provides a form of overflow when the bucket is positioned in the basin of the sink and filled with water. This overflow is possible because the at least one opening places an interior volume of the bucket and the basin of the sink in communication with one another
Thus, the present invention provides a utility sink for the hand washing of fabrics that has a removable bucket. When the bucket is suspended above the basin of the sink, the bucket can be filled with water for the hand washing of clothes. The bucket openings place the interior volume of the bucket with the basin such that when the water level in the bucket exceeds the height of the openings, the water in the bucket overflows into the basin and can flow down the drain.
Moreover, once the bucket is filled with water, the bucket can be temporarily removed from the basin of the sink to make the sink available for other uses while hand washing, soaking, and the like of clothes is performed in the bucket. Then, the bucket may either be returned to the sink, or one of the openings may be used as a pour spout to empty the water contained in the bucket back into the sink to drain.
When the bucket is suspended above the basin, this configuration also provides a form of overflow rinsing. The clothes to be rinsed are placed in the bucket which is suspended in the basin. Water from a faucet fills the bucket until the water begins to overflow from the openings of the bucket into the basin. The continual flow of water into and out of the bucket rinses the clothes contained the bucket. Because the clothes do not cover the drain, the chance that the drain will be blocked during rinsing is minimalized. Thus, clothes can be rinsed without close observation by the cleaner.
These and still other advantages of the invention will be apparent from the detailed description and drawings. What follows is merely a description of a preferred embodiment of the present invention. To assess the full scope of the invention the claims should be looked to as the preferred embodiment is not intended to be the only embodiment within the scope of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a utility sink with a bucket, a shallow tray, and a base tray shown removed from the sink;
FIG. 2 is a perspective view of the utility sink with the bucket positioned in the basin of the sink;
FIG. 3 is a perspective view of the utility sink with the bucket positioned in the basin of the sink and the shallow tray placed over the bucket;
FIG. 4 is a perspective view of the sink;
FIG. 5 is a cross-sectional side view of the sink taken along line 5 - 5 of FIG. 4 ;
FIG. 6 is a cross-sectional side view of the sink along line 6 - 6 of FIG. 4 ;
FIG. 7 is a perspective view of the bucket;
FIG. 8 is a top plan view of the bucket;
FIG. 9 is a cross-sectional side view of the bucket along line 9 - 9 of FIG. 8 ;
FIG. 10 is another cross-sectional side view of the bucket along line 10 - 10 of FIG. 8 ;
FIG. 11 is a perspective view of the shallow tray;
FIG. 12 is a top plan view of the shallow tray; and
FIG. 13 is a cross-sectional side view of the shallow tray along line 13 - 13 of FIG. 12 ;
FIG. 14 is another cross-sectional side view of the shallow tray along line 14 - 14 of FIG. 12 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 , the utility sink 10 is shown which includes a sink 12 with a basin 14 , a rack 16 (shown hung on a wall in FIG. 1 ), a bucket 18 (shown on a countertop 20 in FIG. 1 ), and a shallow tray 22 (shown hung on the wall in FIG. 1 ). A faucet 24 that provides water extends over the sink 12 .
Referring now to FIGS. 4-6 , the sink 12 has a flanged portion 26 that extends from the basin 14 . As shown, the flanged portion 26 of the sink 12 is rectangular with rounded corners. The flanged portion 26 may assist in supporting the sink 12 in the countertop 20 . The flanged portion 26 and the basin 14 meet an upper edge 28 of the basin 14 . The upper edge 28 provides a radiused transition between the flanged portion 26 and the basin 14 . The basin 14 then extends down along side walls 30 to a base 32 of the sink 12 . The base 32 of the sink 12 has a drain 34 which can be connected to a waste water pipe (not shown).
As the side walls 30 basin 14 extend from the upper edge 28 down towards the base 32 and the drain 34 , they angle slightly inward (i.e., towards the drain). Likewise, the base 32 angles slightly downward to the drain 34 . This geometry encourages any water filling the basin 14 to be directed towards the drain 34 .
Referring now to FIGS. 7-10 , further details of the bucket 18 are shown. The bucket 18 has walls including a base portion 36 and side portion 38 extending to a lip 40 . The side portion 38 angle outward from the base portion 36 . The side portion 38 have a transition 43 into the lip 40 . The walls have at least one opening 42 formed therein. As shown, the bucket 18 has two such openings formed proximate the transition 43 spanning the side portion 38 of the walls and the lip 40 .
Referring now to FIGS. 11-14 , the shallow tray 22 is shown in further detail. The shallow tray 22 has a flat portion 44 having a plurality of holes 46 . The flat portion 44 can also include a large hole 48 that may be suitable for hanging the shallow tray 22 from a hook 49 , such as is shown in FIGS. 1 and 2 , so that the shallow tray 22 can be dried. The flat portion 44 has short side walls 50 that extend to an outer rim 52 . At least one opening 54 is formed in the shallow tray 22 . As shown, the shallow tray 22 has two openings 54 formed in the short side walls 50 and outer rim 52 .
Referring back to FIG. 2 , the utility sink 10 is shown with the rack 16 inserted into the bottom of the sink 12 and the bucket 18 received in the basin 14 . In this arrangement, the lip 40 of the bucket 18 contacts the upper edge 28 of the basin 14 of the sink 12 to suspend the bucket 18 in the basin 14 . It is contemplated that in some configurations, the lip 40 may cover at least half of the upper edge 28 of the basin 14 .
The rack 16 may provide additional support for the bucket 18 , particularly if the bucket 18 is filled with water. Further, the rack 16 covers the drain 34 . The rack 16 has a structure that permits water to flow past the rack 16 and down the drain 34 , but will prevent items such as clothing from clogging the drain 34 . For example, the rack 16 may have a mesh surface similar to the shallow tray 22 or be a wire tray.
It is also contemplated that the bucket 18 may not be suspended in the basin 14 , but rather solely supported by the rack 16 . Such a configuration would require constructing the rack 16 and bucket 18 such that for a given sink depth, the lip 40 of the bucket does not engage the upper edge 28 of the sink 12 . In such an arrangement, it is contemplated that as the openings 42 would still be in the basin 14 , that the openings 42 could still perform an overflow function and, as the bucket 18 sits on the rack 16 so that the bucket does not block the drain 34 , the overflow water would be permitted to flow down the drain 34 .
Importantly, when the bucket 18 is suspended in the basin 14 (or placed on a rack 16 in the basin 14 ), the openings 42 of the bucket 18 place the inner volume of the bucket 18 and the basin 14 in fluid communication with one another. Thus, when the bucket 18 is filled with water by the faucet 24 and the water level in the bucket 18 reaches the openings 42 , the excess water overflows through the openings 42 and into the basin 14 of the sink 12 .
It should be appreciated that in addition to providing overflow capabilities, the openings 42 of the bucket 18 may serve as a pouring spout. This may be beneficial when the bucket 18 is filled with water, the clothes and cleaner are placed in the bucket 18 , and left to soak outside of the basin 14 . When the water in the bucket 18 needs to be emptied, the bucket 18 may be tilted such that the water runs out of one of the openings 42 . The openings 42 may be formed on a non-vertical surface for surface to easy pouring. For example, if the openings 42 are formed on the angled side portion 38 of the walls as shown, it reduces the angle at which the bucket 18 must be tilted before pouring action begins (i.e., the water level will more quickly approach the openings 42 when the side portion 38 of the walls are angled).
Further the openings 42 of the bucket 18 can serve as handles for lifting the bucket 18 . In one form, the lip 40 is raised around the openings 42 such that, when the lip 40 contacts the upper edge 28 of the basin 14 , the openings 42 can be accessed from between the bucket 18 and the sink 12 . This provides an ergonomic structure for lifting as the fingers of the individual lifting the bucket 18 from the sink 12 can go into the openings 42 from the outside, rather than the inside, of the bucket 18 .
Referring now to FIG. 3 , the utility sink 10 of FIG. 2 is shown with the shallow tray 22 further placed on top of the bucket 18 . The outer rim 52 of the shallow tray 22 may mate with the lip 40 of the bucket 18 . In this arrangement, the openings 54 of the shallow tray 22 may nest or partially nest in the openings 42 of the bucket 18 . This arrangement makes it easy to lift both the bucket 18 and the shallow tray 22 at the same time. When using the openings 42 as a pouring spout, it is also contemplated that the outer rim 52 of the shallow tray 22 may be held against the lip 40 of the bucket 18 , such that pouring can occur out of unobstructed openings 42 while retaining any solid items, such as clothing, in the bucket.
The shallow tray 22 may also be used as a scrubbing surface during the hand washing of fabrics. In particular, the plurality of holes 46 located in the flat portion 44 provides a surface with sufficient abrasion for scrubbing while also permitting the water to pass through it. It is contemplated that scrubbing may occur when the shallow tray 22 is mated to the lip 40 of the bucket 18 or when the shallow tray is separated from the bucket 18 .
Thus, the present invention provides a utility sink that can be used to hand wash clothes or other fabric items. As the bucket 18 can be suspended in the basin 14 , hand washed clothes are less likely to come into contact with contaminants found on the inner surface of a basin 14 of the sink 12 . Moreover, since the bucket 18 can be removed from the sink 12 during soaking, the utility sink 10 can be used for other operations while the clothes are being soaked.
Although the present invention has been described with reference to washing clothes, it is contemplated that the utility sink may be useful any application in which it is desirable to have a bucket that can be suspended by, but is also removable from, a basin.
Many modifications and variations to this preferred embodiment will be apparent to those skilled in the art, which will be within the spirit and scope of the invention. Therefore, the invention should not be limited to the described embodiment. To ascertain the full scope of the invention, the following claims should be referenced.
INDUSTRIAL APPLICABILITY
The invention provides a utility sink for the hand washing of clothing. | A utility sink system is disclosed comprising a sink and a bucket. The sink has a basin extending from an upper edge to a drain. The bucket has walls extending to a lip and has at least one opening formed therein. The lip is configured to contact the upper edge of the basin such that the bucket is suspended in the basin. The at least one opening of the bucket, in addition to facilitating handling, may provide a form of overflow when the bucket is suspended in the basin of the sink, such that the at least one opening places an interior volume of the bucket and the basin of the sink in communication with one another. Further, the at least one opening of the bucket may provide a pouring spout. | 3 |
BACKGROUND OF THE INVENTION
The subject of the invention is a digital system for computing of the values of composite arithmetic expressions of numbers in a binary system, designed in particular for computing of the values of polynominal expressions ##EQU2## X IJ , ESPECIALLY OF THOSE WITH BIG VALUES OF N AND WITH NUMBERS X IJ POSSESSING MANY SIGNIFICANT BITS. The system is mainly designed for use in large computer and computers systems, especially in specialized high-speed processors for numerical computations and in other high-speed digital systems performing arithmetic operations. The system may also be used for simultaneous computations of several independent arithmetic expressions as well as for the multitask collisionfree work with several different computers
In the known designs of electronic digital systems, the computation of composite arithmetic expressions usually amounts to performing successive arithmetic operations, the results of which being, in turn, the arguments of successive operations of these expressions until a final result is obtained. Fairly well known are electronic devices and digital systems for fast performance of multiplications and additions. These operations are the basic ones when computing the values of many arithmetic expressions, and particularly polynomial ones ##EQU3## X IJ . In this case, the speed of multiplication is most important for this operation is far more time-consuming than addition. There exist many digital systems suited to a pipeline processing of information, ensuring very high effective speed of information processing and especially very fast execution of long sequences of multiplications and additions. In previously known electronic digital systems for very fast multiplication of two binary numbers, all partial products, necessary to obtain the final product, assigned to successive groups of multiplier bits, are simultaneously added in parallel to one another. In the multiplying system of 48-bit numbers, where the individual partial products are attributed to the pairs of successive multiplier bits, 24 such products are added simultaneously. The digital system performing this operation consists of 22 carry-save adders and 1 carry propagation adder. The above mentioned adders are connected together in a multilayer cascade, containing in seven layers respectively 8, 5, 3, 2, 2, 1, 1, carry-save adders and in the 8th layer -- carry propagation adder. All these adders form one switching network and do not contain storing elements. The time of performing the addition of 24 partial products in such a system of adders is the sum or the maximum time of propagation of signals through 7 one-position adders connected in series and the time of propagation through 1 carry propagation adder with approximately 90 positions; the latter adder contains complex carry-skip circuits for minimization of the maximum time of carry propagation. Partial products being added in the described set of adders represent the multiples of multiplicand shifted with respect to one another, assigned to the pairs of multiplier bits representing the integers from 0 to 3. To avoid the time-consuming determination of three-fold multiplicand, which requires an extra addition of the multiplicant and the shifted multiplicant, the presented multiplication system contains a switching network which transforms the multiplier in parallel. Output signals of this network, assigned to the successive groups of multiplier bits, represent the numbers -2,- 1,0,1,2, instead of the numbers 0,1,2,3. In the described multiplication system, the double multiplicant is obtained by shifting the multiplicand by one bit position to the left, and the negative multiples of the multiplicand -- by negating the bits of the positive multiples and the addition of correcting "one" in the least significant binary position. The multiplying system containing the described set of adders has been described in the following papers: C. S. Wallace "A Suggestion for a Fast Multiplier", The Institute of Electrical and Electronics Engineers, Transactions on Electronic Computers, volume Ec-12, pages 14-17, February 1964; T. G. Hallin, M. J. Flynn "Pipelining of Arithmetic Functions", The Institute of Electrical and Electronics Engineers, Transactions on Electronic Computers, volume EC-21, pages 880-886, August 1972; J. W. Gawrilow, A.N.Puczko "Arifmeticzeskije ustroistwa bystrodiejstwujuszczich elektronnych cifrowych wyczislitielnych maszin" /Arithmometers of Fast Electronic Computers/ -- Publ. "Soviet Radio", Moscow 1970, pages 133-180; and carry, skip circuits, also named carry, look-ahead circuits, in the paper: O. L. MacSorley "High Speed Arithmetic in Binary Computers", Proceedings of the Institute of Radio Engineers, volume 49, No. 1, 1961, pages 67-91. In the previously used computers and digital systems, having the structure suited to the pipeline processing of information, the individual layers of switching networks, processing the information, are separated from each other by the layers of registers to provide gradual performing of the parts of different operations at the same time in different individual layers of the switching networks. Processing the successive information being performed in the individual layers of such computers and systems with constant frequency, depends upon the maximum delay of the layer. The pipeline processing of information has been described, among others, in the papers: M. J. Flynn "Pipelining of Arithmetic Functions", The Institute of Electrical Engineers, Transactions on Electronic Computers, volume EC-21, pages 880-886, August 1972; T. C. Chen et al. "Introduction to Computer Architecture", chapter 9, page 417, Publ. Science Research Associates, Chicago, USA, 1975.
A drawback of the known computers and digital systems, particularly those intended to perform composite computations of great accuracy, is a relatively long time of executing the individual multiplications and additions. Even in the case of very fast adders, a considerably part of this time is consumed by the carry propagation. The carry propagation time, being the time of delay in numerous operations performed while computing of composite arithmetic expressions, has a considerable influence upon the total time of computation.
The aim of the present invention is to remove this drawback and to eliminate, as much as possible, all such information processing, including which have a character of series processes, carry propagation processes, which the end operations of multiplication and addition.
SUMMARY OF THE INVENTION
This aim has been achieved by the application of a logical structure of the digital system, which enables the pipeline processing of information only at the initial and medium stage of the individual multiplications and additions, appearing in the computed arithmetic expressions, and by application of unfinished results of these operations as operands of the successive operations multiplications and additions, appearing in those computations. This leads in consequence to almost full elimination of time-consuming carry propagation processes which usually are the final stage of multiplications and additions.
A digital system for computation of the values of composite arithmetic expressions, according to the invention, is dessigned for computation of the values of polynominals of an arbitrary degree of one or several variables, function series, scalar products and of the other computations on vectorized data for vectors of a large number of components, where the operands and results of computations are numbers presented in a binary system, usually in the complementary one, or the form of sign-magnitude done, with the fixed- or floating-point. The digital system comprises a digital processing unit used to form partial products, preferably in the multiplicand of multicand multiples shifted with respect to each other, which are the summands of a full product of a number by a sum of numbers, and to reduce the number of these summands and the summands which are introduced additionally to the processing unit, to a smaller number of summands the total sum being unchanged. The digital system comprises also a set of parallel registers used to store the operands introduced from the outside of the system to the system, which will be introduced to the processing unit, and to store the intermediate results, introduced to the register set from the processing unit and which will be introduced again to the processing unit. Here the parallel register is an arbitrary digital circuit to which the signals representing bits of a single binary number are simultaneously introduced, so that they may be stored there, and then removed from it simultaneously during the period of time required to perform the given task. The register set contains at least two parallel first registers storing reduced summands as multiplier summands, and at least two parallel second registers storing reduced summands for the successive adding to other operands or intermediate results. Parallel first registers used for storing the multiplier summands, together with the processing unit form the parallel information loops, through which the intermediate results in the form of two or more reduced summands, obtained at the processing unit outputs, are again introduced to the inputs of the processing unit as the summands of the multiplier which is one of the two operands for the successive multiplication. The above mentioned first registers storing the multiplier summands serve also for introducing the multiplier or multiplier summands from outside the system to the processing unit. The second registers and the processing unit form the separate parallel information loops, through which the intermediate results in the form of two or more reduced summands, obtained at the processing unit outputs, are again introduced to the ijnuts of processing units, as the summands for the successive additions. Through these second registers, or separate parallel registers of register set, the additional summands for the successive additions are also introduced from the outside of the system to the processing unit. Of advantage is the application of the processing unit reducing the number of all summands to two, their total sum being unchanged, and the application of two registers storing the multiplier summands, as well as the application of two registers storing the reduced summands for addition, or several pairs of registers storing several pairs reduced summands, for several independent intermediate results. The logic structure of a processing unit is adjusted for a simultaneous forming of many or all partial products being the summands of full product of two operands; the first operand is the multiplicand which is introduced in parallel to the processing unit from the multiplicand register, and the second operand is the multiplier composed of two or more multiplier summands being introduced simultaneously to the processing unit from the registers storing multiplier summands. The formation of the above mentioned partial products is performed parallelly without execution of the effective addition of multiplier summands, it means without carry propagation along the multiplier summands, preferably as in the patent application: Method for binary multiplication of a number by a sum of two numbers and a digital system for implementation thereof, U.S. Patent Application Ser. No. 802,187. Here, the digital system for computation of the composed arithmetic expressions, being the subject of the present invention can be a separate construction module, as well as a set of several circuits connected together, which form more than one module or are the parts of one module.
To increase the efficiency of the digital system according to this invention, the processing unit has a layer structure with layers containing the switching networks, separated by the layers containing parallel registers. The layers of the switching networks of the processing are adjusted to the parallel processing informations, that is they are built in such a way, that the maximum number of their logical elements, through which the information signals propagate in series, does not depend upon the number of bits of the binary numbers being processed. This maximum number of logical elements is small and preferably equals from 2 to 8 simple logical elements. The separating layers of parallel registers enable independent, gradual, pipeline processing of information in the successive layers of the switching networks of the processing unit. The successive layers of the switching networks have a logical structure adjusted to form the partial products, preferably in the form of multiplicand multiples shifted in relation to each other, these being the summands of a full product of a number by a sum of numbers, and then to reduce gradually the above mentioned product summands, together with the summands introduced additionally to the processing unit, to a smaller number of summands, preferably to two summands, their total sum being unchanged. The system operates synchronously with a determined frequency, adjusted to the logical structure of the processing unit and to the operating speed of its logical elements. This frequency depends upon the maximum delay introduced by one layer containing the switching networks and one layer containing the registers of the processing unit together. With this very frequency, the reduced summands are introduced simultaneously to all layers of registers of the processing unit from the preceding layers of the switching networks of this unit. In other words, the pipeline processing of information is performed in the successive layers containing the switching networks of the processing unit.
In particular, the processing unit has a logical structure adjusted to reduce the number of summands to two, with their total sum being unchanged the layer of switching networks of this unit, used to form the partial products permits a parallel forming of all partial products of a full product of a number by a sum of two numbers, that is, of a full product of multiplicand by two summands of multiplier. These partial products are, either shifted with respect to each other multiplicand multiples expressed by numbers -1, 0,+1, where each multiplicand multiples is assigned to one pair of bits corresponding to another taken from two multiplier summands, or shifted with respect to each other multiplicand multiples expressed by numbers -2,-1,0,+1, +2, where each multiplicand multiple is assigned to one pair of two-bit groups of bits taken from two multiplier summands, of advantage here is the the method according to the patent application: Method for binary multiplication of a number by a sum of two numbers and a digital system for implementation thereof, U.S. Pat. Application Ser. No. 802,187. This method permits formation of the correct multiple of multiplicand for each partial product assigned to a single pair of bits, taken from both multiplier summands, on the basis of this pair of bits, and eventually of the sign bits of both multiplier summands, and for each partial product assigned to the single pair of two-bit groups of bits, taken from both multiplier summands, on the basis of a pair of five-bit groups of bits and, eventually of the sign bits of both multiplier summands. In case of a binary complementary system, the sign bits are necessary only for determining the partial product assigned to the sign position of the multiplier, or assigned to the group of positions containing the sign position. Multiplicand multiples corresponding to the numbers -2, -1,0,+1,+2 are obtained from the single multiplicand in such a way, that the doubled multiplicand is obtained by shifting the multiplicand by one position to the left, and negative multiples -- by negating the bits of positive multiples and adding the correcting "one" at the least significant position.
In particular, the layers of the switching networks of the processing unit, designed to reduce gradually the partial products formed in this unit and intended for adding the summands introduced to this unit, to a smaller number of summands their total sum being unchanged, consist of coders having p one-bit inputs and r one-bit outputs; such coders provide a zero-one signal combination of r coder outputs which represents a binary coded sum of "ones" being represented by zero-one signals at the p inputs of the coder. In particular, the layers of these switching networks of the processing unit are composed of coders with 8 or 9 inputs and 4 outputs, having weights of the output bits equal to 4,2,2,1, or 8,4,2,1, or of coders having 7,6,5 or 4 inputs and 3 outputs, with weights of output bits 4,2,1, as well as of coders having 3 inputs and 2 outputs, with weights of the output bits 2,1, that is, in the last case, of one-position binary adders. The individual layers of the switching networks of the processing unit usually consist usually of one, two, three or four layers of such coders, which are not connected to each other within one layer of coders. A single series of such p input and r output coders, being not connected to one another, reduces, in parallel connection, p summands to r summands, presented in binary system, their total sum being unchanged. Of advantage application of coders with 3 inputs and 2 outputs, that is one-position adders, in the layers of the switching networks of the processing unit. One series of such one-position adders, not connected to each other, being one multi-position binary carry-save adder, reduces three summands represented in binary fashion to two summands, their total sum being unchanged.
The digital system according to the invention, includes in particular, a parallel adder designed for adding the summands reduced in the processing unit. This adder is connected to the outputs of the processing unit, or to the outputs of registers of the register set. When the processing unit reduces the number of summands to two, this adder is a two-summand one, and in case of a greater number of the reduced summands obtained at the outputs of this unit, the adder is adjusted to a greater number of summands. Of advantage is the application of an adder possessing a layer structure, with layers containing the switching networks, separated by layers of registers; this adder is adjusted to pipeline execution of successive additions, these being synchronized with a pipeline processing of information in the processing unit. The application of an adder to the system is aimed at obtaining the final result of computation in the form of one number in the required binary system.
The output of the adder adjusted to pipeline processing of information or, more precisely, to pipeline execution of successive additions, is connected, in particular, through a multiplicand register of the register set, with a parallel input of the processing unit, this input being designed for the introduction of multiplicand. This permits such multiplications occurring in arithmetic expressions, where both multiplication operands are the sums of two or more summands.
It is beneficial if in the digital system according to the invention, the loops, through which the intermediate results, obtained at the outputs of the processing unit are introduced again at its inputs, comprise two parallel registers of the register set, where the reduced summands for addition are stored, and comprise only one last layer of switching networks of the processing unit. The above-mentioned intermediate results, in the form of pairs of reduced summands, are again reduced together with the other summands in the last layer of the processing unit, to two summands, their total sum being unchanged. Application of the loops, containing only one layer of the switching networks of the processing unit, permits computation of the values of polynomials ##EQU4## x ij for the large values n with such a speed, that the average multiplication time is only slightly longer than the time of one cycle of pipeline processing in one layer of the processing unit, and the additions, occurring in the polynomials, in most cases do not influence the total time of computation.
In particular the system according to the invention, contains several pairs of parallel registers, in which the intermediate results, introduced from the processing unit, in the form of pairs of the addition summands, are stored. From each of the pair of these registers, the pair of summands can be introduced again to the processing unit, or to the pair of the parallel registers of multiplier summands. Introduction of these summands to the multiplier summand registers is performed either directly, or through one or several layers of the processing unit, wherein these summands together with other summands are reduced, their total sum being unchanged. Simultaneous storage of several intermediate results in the form of pairs of reduced summands, and their introduction again to the processing unit, and/or to the multiplier summand registers, enables computation of several polynomial expressions with various locations of parentheses.
The system according to the invention is also such a system, where each loop, formed by the processing unit and some registers of the register set, comprises k layers of parallel registers and of single parallel registers together, being connected in series, through which the pipeline processed information is transmitted successively, to enable an simultaneous, independent computation of k arithmetic expressions. The time of information circulation in each loop formed by the processing unit and some registers of a register set, is k times longer, than the time of a pipeline processing in one layer containing switching networks in the processing unit. The choice of the number k depends mainly on the number of layers of the switching networks of the processing unit. In case the information processing occurs in the processing unit only, the prefered number k is equal to the number of layers of the switching networks in this unit. Arithmetic expressions being computed in the digital system may belong either to one problem, being solved by one program, or to several various problems, being solved in a collision-free manner, when this digital system cooperates with k different computers, performing separate independent programs. One of the aims of the latter application of the digital system is decreasing the speed of computation of each of k arithmetic expressions, alleviating the requirements for the speed of memories cooperating with this digital system.
The digital system according to the invention comprises, in particular, a parallel adder adjusted to a pipeline performance of the successive additons. This adder, the processing unit, and some registers of the register set jointly form an additional loop. This loop contains 2k layers of parallel registers and of single parallel registers, through which the pipeline processing of information is performed successively. Information circulation time in this additional loop is twice as long as in the other loops of the digital system. It is advantageous when this loop also contains the multiplicand register of the register set. This permits multiplication, when both arguments are the sums of two or more summands. In case of large enough number of registers storing the reduced summands, such a solution permits computation of the values of expressions with an arbitrary location of parentheses.
The operation of the digital system wherein the processing unit, containing the layers of the switching networks, separated with the layers of registers, reduces the total number of summands to two, and wherein these both reduced summands of final result are added in an adder connected to the outputs of the processing unit, is described below.
The digital system operates synchronously with a frequency, permitting a pipeline processing of information in the successive layers of the switching networks of the processing unit. With identical frequency, the operands of the arithmetic expression being computed, namely operands of its products and sums, are introduced at the set inputs of the system, in the sequence which depends on the form of this expression. Computation of the product of the two operands requires a simultaneous introduction of multiplicand and multiplier to the inputs of this layer of the switching networks of the processing unit, wherein the partial products being the summands of the full product are formed in parallel. A multiplicand is introduced to the processing unit through the register of multiplicand, and a multipler -- is introduced through one of the registers of multiplier summands. In the mentioned layer of the processing unit, multiplication is replaced by addition of many summands being partial products of the full product being computed. A synchronous introduction of the additional summands for adding to this product only increases the total number of summands being reduced in processing unit. In the successive layers of the processing unit the number of summands is gradually reduced, their total sum being unchanged. The summands of the computed product, reduced in the processing unit to two summands, are next introduced either to registers storing the reduced summands, if they ought to be added to the other operands of the expression being computed, or to the registers storing the multiplier summands, if their sum ought to be multiplied by the successive operand. In the last case, this successive operand of multiplication is introduced to the processing unit as multiplicand simultaneously with the multiplier summands, stored in their registers. As result of this operation of the processing unit, two reduced summands of the successive intermediate result are obtained on its outputs. They are introduced again, either to the registers storing the reduced summands, or to the registers storing the multiplier summands, depending on whether their sum ought to be added to other operands of the arithmetic expression, or whether it ought to be multiplied by its other operands. When the computed intermediate result ought to be added to the content of the registers storing the reduced summands, the content of these registers is introduced to the processing unit during the reduction therein of the number of the summands of this intermediate result. The value of the whole computed arithmetic expression is also obtained in the form of two summands at the outputs of the processing unit. After addition of these summands in the adder, the final result of computation is obtained at its output. The described method of computation of the value of a polynomial, or a polynomial expression with parentheses, requires only execution of one effective full addition with carry propagation.
The main advantage of the digital system, which is the subject of the invention, is its very high operating speed, obtained due to the application of the pipeline processing of information only at the initial and intermediate phases of execution of multiplications and additions, as well as making use of these unfinished results, in a form of groups of several summands, most often pairs of summands, as the operands of the next multiplications and additions. Owing to this, the time-consuming carry propagation processes, being usually the final phase of the multiplications and additions, have been almost fully eliminated in the digital system. In consequence, the computation of the values of composite arithmetic expressions in this digital system is performed without carry propagation along the processed operands, if the final result of this computation is in the form of two summands, or it requires only one process of carry propagation during the last addition of two summands, if the final result is in the form of one number in a required binary system, for example in the complementary one, or in the form sign-magnitude.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be presented by two examples of embodiment shown in FIGS. 1 and 2, in which:
FIG. 1 shows a block diagram of the diagram of the digital system described in example I, and
FIG. 2 shows a block diagram of the digital system described in example II.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
EXAMPLE I
The digital system presented in FIG. 1 contains a processing unit P, two parallel registers A and B storing the multiplier summands, parallel multiplaced register C, two registers D and E storing the addition operands, two parallel registers F and H storing the summands reduced in the processing unit P, as well as a parallel adder S. The processing unit P has five layers 1,3,5,7, and 9 containing the switching networks, separated by four layers 2,4,6 and 8, containing parallel registers. Adder S is a two-summand parallel adder with layer structure, having three layers 11,13 and 15 containing the switching networks, separated from one another by two layers 12 and 14 of parallel registers. All registers of the system that is both, the registers A,B,C,D,E,F,H, as well as the registers which form the layers 4,6,8,12,14, are double registers of a master-slave type, suited to pipeline information processing in the system. The control signals introduced room the outside of the system cause the storage of the zero-one signals supplied at the inputs of the above mentioned registers. To the processing unit P the operands are introduced from the outside, through registers A,B,C,D,E. Registers A and B and the processing unit P together forming the parallel loops, through which the intermediate results, obtained at outputs of layer 7 of the processing unit P, in the form of pairs of the reduced summands, are introduced again, as pairs of multiplier summands, to the processing unit P at the inputs of layer 1. Registers F and H and the processing unit P form parallel loops too. The intermediate results obtained at the outputs of layer 9 of the processing unit P are introduced again through these registers to the inputs of layer 9 as pairs of summands, being next added to the next summands reduced in the processing unit P. The outputs of registers F and H are also connected with the inputs of adder S, where the addition of the two summands of a final result takes place, these summands are introduced at the inputs of adder S from the processing unit P through the above mentioned registers F and H. The output of the adder S is a parallel external output of the entire digital system. Each of the inputs and outputs of the specified registers, of the processing unit P and of the adder S is adjusted to a parallel introducing or leading out of all bits of one binary number. The system is adjusted to the computation on 32-bit numbers. In the successive layers 1,3,5,7 and 9 of the processing unit P, containing the switching networks, the pipeline processing of information is performed, namely: preparation of the partial products in layer 1 and a gradual reduction of a number of summands in layers 3,5,7 and 9. The layer 1 of the processing unit P consists of many simple switching networks, at the outputs of which all bits of 17 partial products are obtained simultaneously, these partial products being the summands of the product of 32-bit multiplicand and of multiplier composed of two 32-bit summands. The individual partial products are assigned to the pairs of binary positions of multiplier and represent, shifted with respect to each other, the multiples of multiplicand corresponding to the numbers -2, +1,0,+1+2. Each of the layers 3,5,7,9 consists of two layers of one-position adders; every adder had three one-bit inputs and two one-bit outputs, which are not directly connected one to another within a single layer of adders. These adders form the series, each series reduces three summands to two, their total sum being unchanged. In particular, layer 3 consists of two layers of one-position adders containing correspondingly 0 and 4 series of adders; layer 5 consists of 3 and 2 series of such adders, and each of layers 7 and 9 consists of two single series of one-position adders. Layer 3 reduces 17 partial products plus 2 addition summands to 9 summands with identical sum, layer 5 reduces the number of summands from 9 to 4, and each of the layers 7 and 9 reduces the number of summands from 4 to 2. Layers 1,3,5,7 and 9 are separated from one another by layers 2,4,6 and 8 containing successively 17,9,4 and 2 parallel registers, whether 17 partial products and 9,4 and 2 reduced summands are successively stored.
The operation of the digital system shown in FIG. 1 will be presented on an example of computation of an arithmetic expression ##EQU5## [(x i y i z i +w i )v i +u i t i +p i +q i +r i +s i ], which requires execution of 400 multiplications and 699 additions. The time of computation of the value of the presented expression consists of the time of 400-fold transit of the information signals through a single layer of the switching networks and a single layer of registers, plus the time of a single transit of the information signals through all layers of the processing unit P and adder S. If a period of time of pipeline processing of information in one layer is assumed to be the unit of time T, this time being equal in the described system to the maximum transit time of information through two one-position adders connected in series and through one parallel register of the master-slave type, then the time of computation of the value of the above mentioned expression will be equal 400T+5T+3T=408T. Computing procedure is as follows. Pairs of product operands x 1 ,y 1 ; x 2 ,y 2 ; x 3 ,y 3 ; x 4 ,y 4 are supplied to the inputs of layer 1 of processing unit P through registers A,C in the four successive periods T designated by T 1 , T 2 ,T 3 , T 4 . The pairs of summands of products x 1 y 1 ; x 2 y 2 , x 3 y 3 , x 4 y 4 , obtained successively at the outputs of layer 7 of the processing unit P, resulting from the operation of the processing unit, are introduced again in periods T 5 , T 6 , T 7 , T 8 , as the pairs of multiplier summands, through registers A,B, to the inputs of layer 1 of unit P. At the same time, there are introduced successively through register C the numbers z 1 , z 2 , z 3 , z 4 as the successive multiplicands, and after a delay equal to one period of T successively the numbers w 1 , w 2 , w 3 , w 4 as the added summands, these last ones are introduced through register D to the inputs of layer 3 of the unit P. As a result of operation of processing unit P, at the outputs of its layer 7 there are obtained successively the pairs of the summands representing the intermediate results x 1 y 1 z 1 +w 1 , x 2 y 2 z 2 +w 2 , x 3 y 3 z 3 +w 3 , x 4 y 4 z 4 +w 4 . These pairs of summands are introduced again to the inputs of the layer 1 of the processing unit P at the periods T 9 , T 10 , T 11 , T 12 through registers A,B as the multiplier summands. At the same time there are also supplied through the register C the numbers v 1 , v 2 , v 3 , v 4 as the multiplicands, and after a delay equal to one period T there are successively introduced to the processing unit P through the registers D, E the pairs of numbers p 1 , q 1 ; p 2 , q 2 ; p 3 , q 3 ; p 4 , q 4 as the added summands. As a result of the operation of processing unit P at the outputs of its layer 7 there are obtained successively the pairs of summands of the intermediate results (x i y i z i +w i v i +p i +q i for i=1,2,3,4. These pairs of summands are introduced successively to layers 8 and 9 of processing unit P in periods t 13 , T 14 , T 15 and T 16 , and therefrom to registers F, H. To layer 9 there are introduced simultaneously in the periods T 14 , T 15 , T 16 , the contents of registers F, H. As a result of this operation, in registers F, H in period T 17 there are obtained two summands of a sum ##EQU6## [(x i y i z i +w i )v i +p i +q i ]. Independently of this, the pairs of product operands u 1 , t i ; u 2 , t 2 ; u 3 , t 3 ; u 4 , t 4 , are introduced in periods T 13 , T 14 , T 15 , T 16 successively, to the inputs of layer 1 of processing unit P, through registers A and C, and after a delay equal to one period T, the pairs of added summands r 1 , s 1 ; r 2 , s 2 ; r 3 , s 3 ; r 4 , s 4 are introduced through registers D, E to the inputs of layer 3 of processing unit P. As a result of the operation of the processing unit P, there are obtained at the outputs of its layer 7 the pairs of the summands representing intermediate results u i t i +r i +s i , successively for i=1,2,3,4. These pairs of summands are supplied successively to layers 8 and 9 of processing unit P in periods T 17 , T 18 , T 19 and T 20 and therefrom to registers F, H, whereas the successive contents of the registers F, H are introduced simultaneously to layer 9 in the periods T 17 , T 18 , T 19 and T 20 . As a result of this, two summands in the registers F, H in the period T 21 are obtained giving the sum equal to ##EQU7## [(x i y i z i +w i )v i +u i t i +p i +q i +r i +s i ]. In a similar way, by supplying to processing unit P, in the periods from T 17 up to T 32 , further operands from x i to s i for i=5,6,7,8 there are obtained in registers F, H in the period T 37 two summands of the sum ##EQU8## [(x i y i s i +w i )v i +u i t i +p i +q i +r i +s i ]. Similarly, two summands of the final result ##EQU9## [(x i y i z i +w i )v i +v i t i +p i +q i +r i +s i ] are obtained in registers F, H in the period T 405 . After adding of these two summands in adder S, containing 3 layers of switching networks 11,13 and 15, the final result in the form of one number in the required binary system at the output of the adder S is obtained in the period T 408 .
Example II. The digital system presented in FIG. 2 is suited to the simultaneous, independent computation of four arithmetic expressions. The system contains processing unit P, the set of parallel registers R and a parallel adder S. The processing unit P has four layers 1,3,5 and 7 containing the switching networks, separated by three layers 2,4 and 6 containing the parallel registers. The set of parallel registers R contains two registers where the multiplier summands are stored, the multiplicand register, and two layers of registers storing reduced summands for addition. Adder S is a two-summand parallel adder of a layer structure, possessing four layers 11,13,15 and 17, containing the switching networks, separated with three layers 12,14 and 16 containing the parallel registers. Similarly as in the previously described digital system, all registers of the system are suited to pipeline processing of information. The processing unit P is built in a similar way, as far as seven layers 1,2,3,4,5,6,7, of the processing unit of the system described in the first example of embodiment are concerned. The system has connections permitting parallel transmitting of intermediate results, in the form of the pairs of the reduced summands, from the outputs of layer 7 of processing unit P to the registers storing the multiplier summands and to the first layer of registers storing the reduced summands of registers set R, as well as the connections permitting transmitting of these intermediate results and the final result from the outputs of layer 7 of processing unit P to adder S. From adder S, the intermediate results are transmitted to the multiplicand register in the set of registers R, and the final result -- to the outside of the system. Operands from the outside of the system are introduced to the parallel registers of the set of registers R. From the multiplicand register and from the registers of the multiplier summands, in register set R, the operands, as well as the intermediate results, are introduced to the inputs of layer 1 of processing unit P, and from the registers of register set R, which store the operands and reduced summands for adding, through registers of the second layer of register set R, to the inputs of layer 3 of processing unit P. The second layer of registers, storing the reduced summands in register set R is thus a buffer layer, introducing a delay equal to the delay of one layer of pipeline processing of information in processing unit P.
The operation of the digital system shown in FIG. 2 will be presented on an example of simultaneous computation of four independent arithmetic expressions, one of which is the same as in the example I, the expression ##EQU10## [(x i y i z i +w i )v i +u i t i +p i +q i +r i +s i ], which requires execution of 400 multiplications and 699 additions. The time of computation of the value of this expression consists of time of 400 circulations of information signals in the loop, comprising all layers of processing unit P, and of the time of a single transit of the information signals through all layers of processing unit P and adder S. Assuming that the unit of time is the previously defined period T, we obtain the time of computation of the given above expression 400+4T+4T+4T=b 1608T. The operands of the computed expression are introduced to processing unit P every fourth period T. Thus, in each period T only one layer of the switching networks of the processing unit P is used for the computation of this expression in a pipeline way. The remaining layers of the switching networks of processing unit P can be used similarly for simultaneous pipeline computing of the three other independent arithmetic expressions. These expressions may belong, for example, to various problems solved collision-free, in case of cooperation of the described digital system with several computers. Taking into account a fact that, in the described embodiment of the digital system, the successive groups of operands are introduced to processing unit P periodically, every fourth period T, that is, with the frequency corresponding to the full operation cycle of unit P, the individual operands may be introduced in the sequence of their indices, that is successively for i=1,2,3,... This simplifies the control of the input information stream as compared with the system presented in example I. The average speed of execution of arithmetic operations in both embodiments of the digital system corresponds approximately to one multiplication perei period T. Additions occuring in the arithmetic expressions do not influence the computation time of these expressions. This estimation does not hold in a case of much greater number of additions than multiplications.
2. List of reference marks to the drawings
A, b--parallel registers storing the multiplier summands
C--multiplicand register
D, e--parallel registers storing the addition operands
F, h--parallel registers storing the reduced summands
P--processing unit
R--set of registers
S--parallel adder
1, 3, 5, 7, 9--layers containing the switching networks of the unit P
2, 4, 6, 8--layers containing the parallel registers of the unit P
10--layer of the registers storing the reduced summands
11, 13, 15, 17--layers containing the switching networks of the adder S
12, 14, 16--layer containing the parallel registers of the adder S | A digital system for computing of the values of composite arithmetic expressions, such as ##EQU1## X IJ WHERE N, K 1 , K 2 , ....., K N ARE ARBITRARY INTEGERS, ON NUMBERS X IJ IN A BINARY SYSTEM FOR APPLICATION IN LARGE COMPUTER SYSTEMS, WITH POSSIBILITY OF A COLLISION-FREE MULTITASK WORK WITH SEVERAL COMPUTERS. The system contains a processing unit for pipeline processing of information to form the partial products for the given multiplicand and multiplier summands. These partial products are the full product summands. It also reduces gradually these summands together with the additional summands of the addition to a smaller number, preferably to two summands. The system contains also a set of registers in which the operands and the intermediate results are stored. The intermediate results in the form of pairs of reduced summands, or of several reduced summands are introduced from the outputs of the processing unit again to the inputs of this same unit, through the set of registers. | 6 |
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The invention relates to the fabrication of integrated circuit devices, and more particularly, to a method of performing Lightly Doped Drain (LDD) implants for High Voltage (HV) and for Low Voltage (LV) polysilicon gate electrodes using one processing sequence thereby enabling the creation of devices that contain both HV and LV polysilicon gate electrodes.
(2) Description of the Prior Art
The continuing striving of the semiconductor industry to reduce device manufacturing costs has been accompanied by a simultaneous emphasis on improving device performance. These objectives have been met in the industry by the continued improvements of a number of interrelated technical disciplines. Key among these disciplines are photolithography and the innovative application of materials combined with new methods of applying processing parameters and processing sequences that are used to create the device features and semiconductor devices. Critical to device performance improvements is the reduction of device dimensions. As an example, the performance of typical Metal Oxide Field Effect Transistors (MOSFET) is critically dependent on the dimensions of the gate electrode that is used in the creation of MOSFET devices. This requirement of creating narrow gate features is closely coupled with the process of photolithography that is used in the creation of the gate electrode. The reduction of gate electrode gate size has been made possible by a confluence of improvements in photolithography (allowing for greater image resolution), in improved photoresist material and in the development of high contrast photoresist material.
Improved etching techniques such as Reactive Ion Etching (RIE) have also contributed to the creation of deep sub-micron device features. With improvements in photo-imaging techniques and advancements in exposure methods, the wavelengths of the exposure sources now reach into the Deep Ultra Violet range. Special techniques such as the application of special layers of material further improve focusing depth and sharpness of focus in creating images in for instance layers of photoresist that are applied to create interconnect lines, vias, contact openings and the like. These techniques are equally applied in the formation of for instance Complementary Metal Oxide Semiconductor (CMOS) devices.
The technique of creating complementary n-channel and p-channel devices has long been known and applied in the semiconductor industry. The salient advantage of these devices is their low power usage due to the fact that two transistors are paired as complementary n-channel and p-channel transistors whereby in either logic state (on/off) of the device, one of the two transistors is off and negligible current is carried through this transistor. The logic elements of Complementary Metal Oxide devices drain significant amounts of current only at the time that these devices switch from one state to another state. Between these transitions the devices draw very little current resulting in low power dissipation for the CMOS device.
The invention addresses an improved method of concurrently creating Lightly Doped Drain (LDD) regions in both high voltage and low voltage CMOS devices, following will therefore be a brief overview of present methods of forming these devices.
A typical n-channel transistor for a CMOS inverter is formed by first forming a p-region (also called tub or well) in the surface of an n-type silicon substrate. Referring to FIG. 1 a , there is shown a cross section of a typical MOS transistor that is formed on the surface of a silicon substrate 10 . A layer 12 of gate oxide is first formed over the surface of the substrate 10 , this layer 12 of oxide serves as a stress relieve layer between the gate of the MOS transistor and the silicon surface. A layer of polysilicon or the like is deposited over the layer of gate oxide 12 and patterned and etched to form the structure 14 of the gate electrode. Source and drain regions ( 16 and 18 respectively) are then formed self-aligned with and adjacent to the gate electrode 14 by implanting of high-concentration n-type impurities into the surface of the silicon substrate 10 . In the era of ULSI devices, the width of the gate has been reduced to below 0.5 um, the distance between the source and the drain region (the channel length) is correspondingly reduced. This sharp reduction in channel length however leads to a significant increase in the concentration of the electromagnetic field close to drain region 18 where this drain region interfaces with the underlying silicon substrate 10 . This sharp increase may lead to leakage current between the drain region 18 and the surrounding silicon of substrate 10 . In addition, hot carriers can be created in the silicon of the substrate 10 and can gain sufficient energy to penetrate into the layer of gate oxide 12 underneath the gate structure 14 resulting in impacting the threshold voltage between the gate 14 and the substrate 10 . This may lead to current flow between the gate electrode 14 and the underlying substrate 10 .
To counteract the increase in the electric field, the art has implemented the formation of Lightly Doped Drain (LDD) regions 20 and 22 that are shown in FIG. 1 b . The LDD regions 20 and 22 form double off-set regions whereby the source and drain regions now contain high n-type impurity concentrations 16 and 18 and low n-type impurity concentrations 20 and 22 . The principle objective of the LDD regions 20 and 22 is to offset the high concentration of the electric field around the drain region 18 . The regions are symmetrically formed around the gate electrode and consist of low-concentrations of n-type impurities 20 and 22 . The profile of the implanted regions 20 and 22 indicates that the impurity concentrations in the p-n junction change gradually thereby extending to the source and drain regions to attenuate the electric field.
With the creation of the LDD regions 20 and 22 , the breakdown between the drain region 18 and the channel region between the source and the drain region has been eliminated. Hot carriers that could affect the threshold voltage are thereby also eliminated. However, the low concentration regions 20 and 22 form high resistivity regions by their nature of being low concentration impurity regions. Since the current flows between the source and drain regions, the regions 20 and 22 are now parasitic resistances that are connected in series between the source and the drain regions. This lowers the drain current and the n-resistance performance of the transistor thereby reducing the performance of the device. Sidewalls 24 and 26 of the gate electrode structure 14 that have been formed on the surfaces of the low-concentration n-source and drain regions further emphasizing this effect. The high electric field that is in effect around the drain region 18 generates hot carriers, some of these carriers may be injected into the lower portion of the sidewall 26 of the drain region 18 . The region of the silicon surface of the n-type impurity 22 becomes depleted of carriers due to the electric field that is created by the hot carriers that have become trapped in the underlying layer of gate oxide 12 . This results in an increase of the threshold voltage of the transistor thereby having a negative effect on the drain characteristics and ultimately on the reliability of the transistor.
The CMOS device can be divided into a low voltage transistor with operating voltages of no larger than about six volts or a high voltage transistor with an operating voltage in excess of thirteen volts. Low voltage transistors are generally used at the logic or intermediate stages of signal processing while high voltage transistors are generally used as current drivers and switches or as serving at input and output stages of the integrated circuit.
The doping for the formation of regions 20 and 22 is typically performed after the gate spacers 26 have been formed by the process of annealing. The implant for the LDD regions can be, dependent on device type, be a Low Voltage LDD (LVLDD) or a High Voltage LDD (HVLDD). The polysilicon gate electrode is, as part of the creation of the gate, doped in order to establish the desired level of electrical conductivity. It is a requirement that this doping is evenly distributed throughout the body of the gate electrode, which requires that the thickness of the gate electrode be reduced. This brings with it a reduction of the implant energy that can be used to create the LDD regions since too high an implant energy would result in implanted ions penetrating the gate electrode into the underlying silicon of the substrate thereby having a negative effect on the breakdown voltage of the device and on the device functionality. A gate electrode that is reduced in thickness results in reduced implant energy for the HVLDD which results in shallow implants in the LDD regions which in turn results in low breakdown voltage of the high voltage MOS devices.
Since the above-indicated high voltage transistors and the low voltage transistors operate in conjunction with each other, it is often desirable to fabricate these devices on the same substrate. A characteristic of the high voltage device is however that it requires a channel region between the source and the drain regions of the device that can withstand a relatively high induced electric field without experiencing avalanche breakdown whereby excessive currents are created due to the formation of electron hole pairs by the electric field. The result is that high and low voltage transistors frequently have different internal dimensions and that they are frequently formed using different processing sequences. This has in the past led to the formation of high and low voltage transistors on different chips. Required in the creation of high and low voltage transistors is large breakdown voltages (in excess of 13 volts, suitable for current drivers), low source to drain channel resistance, low ionization, low levels of electrical fields around the various areas of dopant implants and low leakage currents.
In a typical High voltage/Low voltage CMOS transistor configuration, HV NMOS, LV NMOS, HV PMOS and LV PMOS can be created on the surface of a substrate. The fabrication of these devices typically applies multiple processing steps that are required to optimize the electrical parameters of the HV N-channel and the P-channel devices while maintaining the desired performance parameters of the LV CMOS devices. Any reduction or simplification in these processing steps is therefore highly desirable and contributes to making these devices more competitive and more widely used.
The above indicated problems in the fabrication of CMOS transistors leads to a requirement for alternate methods of creating these devices, methods that counteract the shallow high voltage junction and the resulting low breakdown voltages of the high voltage MOS device. This requirement takes on increased urgency for devices with micron and sub-micron device features where the impact of low breakdown voltage is only further emphasized.
U.S. Pat. No. 5,366,916 (Summe et al.) shows a method for a HV device.
U.S. Pat. No. 5,498,554 (Mei) shows a HV Device with high doping at surface and low doping a bottom junction.
U.S. Pat. No. 5,024,960 (Haken) shows a dual LDD submicron CMOS process for making low and high voltage transistors with common gate.
SUMMARY OF THE INVENTION
A principle objective of the invention is to provide an improved method for simultaneously creating Lightly Doped Drain (LDD) regions for High Voltage and Low Voltage CMOS gate electrodes.
Another objective of the invention is to offset the effect of shallow junction depth for High Voltage CMOS devices thereby reducing potential problems of low breakdown voltage for High Voltage CMOS devices.
Yet another objective of the invention is to simultaneously achieve high breakdown voltage for CMOS devices having HVLDD regions and shallow low voltage junctions for CMOS devices having LVLDD regions.
In accordance with the objectives of the invention a new process is provided whereby LDD regions for HV CMOS devices and for LV CMOS devices are created using one processing sequence. CMOS generally refers to any integrated circuit in which both N-channel and P-channel Metal Oxide Semiconductor Field Effect Transistors (MOSFETS) are used in complementary fashion. The gate electrodes of the invention for both the High Voltage and the Low Voltage devices are created on the surface of a silicon substrate. The High Voltage LDD (HVLDD) is implanted self-aligned with the HV CMOS gate electrode. A gate anneal is performed for both the HV and the LV CMOS devices. The Low Voltage LDD (LVLDD) is implanted self-aligned with the LV CMOS gate electrode. The gate electrodes of the CMOS devices are after this completed with the formation of the gate spacers, the source/drain implants and the back-end processing that is required for CMOS devices.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross section of the Prior Art gate electrode, as follows:
FIG. 1 a shows a cross section of a substrate on the surface of which has been formed a gate electrode with the completion of the implants for the source and drain regions.
FIG. 1 b shows a cross section of the substrate after the LDD regions of the source/drain regions have been formed in addition to the formation of the gate spacers.
FIG. 2 a shows a cross section of a substrate on the surface of which has been created a layer of gate oxide and a polysilicon gate structure, this for a High Voltage device.
FIG. 2 b shows a cross section of a substrate on the surface of which has been created a layer of gate oxide and a polysilicon gate structure, this for a Low Voltage device.
FIG. 3 a shows a cross section of the HV device after the HVLDD implant has been completed.
FIG. 3 b shows a cross section of the LV device after the HVLDD implant has been completed. This implant does not affect the LV device.
FIG. 4 a shows a cross-section of the HV device after the gate anneal has been completed.
FIG. 4 b shows a cross-section of the LV device after the gate anneal has been completed.
FIG. 5 a shows a cross section of the HV device after the LVLDD implant has been completed. This implant does not affect the HV device.
FIG. 5 b shows a cross section of the LV device after the LVLDD implant has been completed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In conventional processing to create CMOS devices, specifically during the creation of High Voltage LDD regions, the gate anneal process is performed prior to performing the HVLDD implant. This results in a shallow high voltage junction due to the fact that the annealed gate oxide (partially) blocks the HVLDD implant. As a result, the (HVLDD) CMOS device has a relatively low breakdown voltage. The invention addresses this problem and provides a method whereby the breakdown voltage performance of the (HVLDD) device is considerably improved.
The invention provides a process whereby the HVLDD implant is performed prior to performing the gate anneal. The HVLDD is further driven into the surface of the substrate during the gate anneal processing step thereby forming a deep and graded junction between the HVLDD region and the surrounding substrate. The result is that the breakdown voltage of the HVLDD device is improved. Furthermore, the layer of gate oxide prevents the HVLDD diffusion from penetrating into the channel region of the HV gate electrode during the gate anneal process thereby increasing the threshold voltage of the HV device. By performing the LVLDD implant after the gate anneal, a desired shallow junction depth is established for the LV device.
The invention therefore provides a process whereby the HVLDD (for HV CMOS devices) and the LVLDD (for LV CMOS devices) can be created simultaneously and whereby both types of the devices have the desired performance characteristics, that is:
high breakdown voltage for the HV device
high threshold voltage for the HV device, and
shallow LDD junction depth for the LV device.
In the following sequence of cross sections, the cross sections that are shown under FIGS. 2 a , 3 a , 4 a and 5 a refer to High Voltage (HV) gate electrode structures while the cross sections that are shown under FIGS. 2 b , 3 b , 4 b and 5 b refer to Low Voltage (LV) gate electrode structures.
Referring now specifically to FIG. 2 a , there is shown a cross section of a semiconductor substrate 10 , a layer 12 of gate oxide is deposited over the surface of the substrate 10 while a HV polysilicon gate 14 has been formed overlying the gate oxide.
The silicon substrate 10 is typically composed of P-type, single crystalline silicon with a <100> orientation. Field Oxide (FOX) regions (not shown) are formed for isolation purposes separating P-channel regions (for PFET's) from the N-channel regions (for NFET's). The FOX region can be created by initially growing a thin layer of silicon oxide using thermal processing and than depositing a layer of silicon nitride. The layer of silicon nitride can be deposited using Low Pressure CVD (LPCVD) of Plasma Enhanced CVD (PECVD) processing. Subsequent steps of photolithography and Reactive Ion Etching (RIE) create the desired pattern in the (oxidation resistant) layer of silicon nitride/silicon dioxide. The layer of photoresist is removed (using plasma oxygen ashing and careful wet cleans) and the FOX layer is thermally grown in an oxygen steam ambient. The layer of FOX is typically between 3000 and 5000 Angstrom thick in the unprotected regions. The layer of silicon nitride is next removed in a hot phosphoric acid solution. P- and N-well regions can than be created in the surface of the substrate by photoresist patterning and respectively blocking either the P-well region or the N-well region. The N-well/PFET region (the P-well region is now blocked by photoresist) can be created by implanting an N-type dopant such as phosphorous at an energy between about 300 and 800 KeV and a dose between about 5E12 and 1E13 atoms/cm 2 . The P-well/NFET region (the N-well region is now blocked by photoresist) can be created by implanting a P-type dopant such as indium or boron at an energy between about 130 and 180 KeV and a dose between about 5E12 and 7E12 atoms/cm 2 . The layers of photoresist and silicon dioxide are removed (the photoresist with plasma oxygen ashing, the layer of silicon oxide using a diluted hydrofluoride acid solution consisting of 50 parts H 2 O and one part HF).
The substrate is now ready for the creation of the layer 12 of gate oxide. This layer typically contains silicon dioxide and is thermally grown in an oxygen—steam ambient at a temperature between about 800 and 1000 degrees C., typically to a thickness between about 30 and 300 Angstrom. The poly gates 14 are created by the deposition of a layer of polysilicon using LPCVD processing at a temperature between about 500 and 650 degrees C. to a thickness between about 1500 and 4000 Angstrom. The layer of polysilicon can be grown using in-situ doping procedures, via incorporation of arsine or phosphine, to a silane ambient. The layer of polysilicon can also be grown intrinsically and doped using a N-type dopant such as arsenic or phosphorous at an energy of between about 30 and 75 KeV and a dose of between about 5E14 and 1E16 atoms/cm 2 . The gate structure is etched using photolithography and RIE processing using SF 6 and Cl 2 as etchants.
The layer 12 of gate oxide for the HV device of FIG. 2 a is grown to a thickness of between 150 and 400 Angstrom in order top provide extra protection during the process of HVLDD implant. In contrast, the layer of gate oxide 16 that is shown in FIG. 2 b for the LV device is grown to a thickness of between about 15 and 100 Angstrom since this layer does not need to provide extra protection during the LVLDD implant.
The difference in thickness between the two layers of gate oxide that is indicated above is achieved as follows:
the thick layer of oxide is grown
a layer of photoresist is used to protect the thick part of the layer of oxide
the thin oxide part is etched using HF or BEO
the photoresist is removed, and
the thin oxide is grown.
FIG. 2 b shows a cross section of the silicon substrate 10 on the surface of which a layer 16 of gate oxide has been deposited. A LV poly gate 18 has been created overlying the layer 16 of gate oxide. The creation of both the layer 16 and the gate structure 18 follow the same procedures as highlighted above under FIG. 2 a and will therefore not be further addressed under FIG. 2 b.
FIG. 3 a shows a cross section of the substrate for the HV device after the HVLDD implant 20 has been completed. Typical LDD implant processing conditions are as follows.
For the P-channel FET: implant p-type dopant species such as BF 2 , for instance at a dose of between about 1.0E13 and 5.0E13 atoms/cm 2 and at an implant energy between about 40 and 60 KeV. For the N-channel FET: implant n-type dopant species such arsenic or phosphorous, for instance at a dose of between about 1.0E13 and 1.0E14 atoms/cm 2 and at an implant energy between about 30 and 80 KeV.
LDD implant processing condition can vary and depend on device design requirements. For instance, other frequently used implant processing conditions for NMOS/PMOS devices are as follows:
LDD implant for a NMOS device using arsenic with an energy within the range of between 1 to 10 keV and a dose within the range of between 1e14 to 1e16 atoms/cm 2
LDD implant for a PMOS implant using BF 2 with an energy within the range of between 1 to 10 keV and a dose within the range of between 1e14 to 5e15 atoms/cm 2 .
The preferred conditions for the HVLDD implant of the invention are as follows:
for NMOS implant using boron with an energy within the range of between 40 to 70 keV and a dose within the range of between 5e12 to 1e14 atoms/cm 2
for PMOS implant using phosphorous with an energy within the range of between 50 to 250 keV and a dose within the range of between 5e12 to 1e14 atoms/cm 2 .
FIG. 3 b shows a cross section of the silicon substrate 10 , the LV gate structure 18 is created on the surface of the substrate 10 . The purpose of the cross section that is shown in FIG. 3 b is to indicate that the HVLDD implant that has been performed as shown in FIG. 3 a has no impact on the LV device that is shown in FIG. 3 b . No further detailing of the cross section of FIG. 3 b is therefore in order. The cross section that is shown in FIG. 3 b therefore implies that proper shielding was applied during the HVLDD implant such that the LV gate structure is not affected during the HVLDD implant.
FIG. 4 a shows a cross section of the silicon substrate with the RV gate structure after the gate structure 14 has been subjected to a thermal gate anneal. The purpose of the gate anneal is to create a protective layer of oxide that surrounds the gate structure 14 in addition to creating a layer of annealed oxide on the surface of the layer 12 of gate oxide.
The process of gate anneal that creates the layer of gate anneal oxide is performed in an oxygen—steam ambient at a temperature between about 800 and 1000 degrees C. The layer of gate oxide that is created in this manner is typically of a thickness between about 30 and 300 Angstrom. This layer of thermal oxide also overlays the layer of gate oxide 12 thereby extending the thickness of this layer 12 to between about 230 and 700 Angstrom.
FIG. 4 b shows a cross section of the substrate on the surface of which a LV gate structure 18 has been created. The LV gate structure 18 has be subjected to a thermal gate anneal, this gate anneal of the LV gate structure has been performed at the same time and using the same processing conditions as the gate anneal that has been performed on the HV device as highlighted under FIG. 4 a . The layer of gate oxide that is created in this manner around the LV gate structure 18 is typically of a thickness between about 15 and 100 Angstrom. This layer of thermal oxide also overlays the layer of gate oxide 16 thereby extending the thickness of this layer 16 to between about 60 and 250 Angstrom.
It must further be noted that the gate anneal, which is performed after the HVLDD has been completed, drives the HVLDD implant further into the surface of the substrate in the source/drain regions of the gate structure 14 and forms a deep and properly graded junction between the source/drain regions and the underlying silicon of the substrate. The sequence of first performing the HVLDD implant after which the gate oxide anneal is performed results in higher breakdown voltage for the HV device.
Furthermore, the layer of gate oxide is in place at the time of the gate anneal process and prevents diffusion of the HVLDD implant into the channel region of the gate structure. This has a positive effect on the threshold performance of the gate electrode by raising the threshold limit of the device.
FIG. 5 a shows a cross section of the substrate after the LVLDD implant 22 has been performed on the LV device. The purpose of showing the cross section as shown in FIG. 5 a is to highlight that the LVLDD implant for the LV device has no effect on the HV device. The cross section that is shown in FIG. 5 a implies that proper shielding was applied during the LVLDD implant such that the HV gate structure 14 of FIG. 5 a is not affected during the LVLDD implant.
FIG. 5 b shows a cross section of the substrate after the LVLDD implant has been performed on the LV device.
The preferred LVLDD implant processing conditions of the invention for NMOS/PMOS devices are as follows:
LDD implant for a NMOS device using arsenic with an energy within the range of between 1 to 10 keV and a dose within the range of between 1e14 to 1e16 atoms/cm 2
LDD implant for a PMOS device using BF 2 with an energy within the range of between 1 to 10 keV and a dose within the range of between 1e14 to 5e15 atoms/cm 2 .
The process of the invention is, with the completion of the LVLDD implant, essentially completed. The gate electrode structure can, from this point on, be completed using the conventional processing steps of completing the spacer formation, of completing source and drain region implant, of forming for instance Anti Reflective Coating on the surface of the gate structure, of saliciding the (source/drain and gate surface) surfaces, of depositing layers of dielectric or passivation and of establishing electrical contacts with the source/drain regions and the surface of the gate electrode.
These latter processing steps are well known in the art while the process of the invention does not depend on and is not influenced by these processing steps that are required to complete the gate electrode. These processing steps will therefore not be further discussed at this time and do not form part of the invention.
The structure of the polysilicon gate can, when observed from above, be of two different kinds. The first is where the structure when viewed from above shows the source and drain regions to be on opposite sides of the polygate without surrounding the poly gate. The second is where the drain is in the center of the polysilicon and surrounded by the polysilicon while the source in turn surrounds the polysilicon of the gate. For both structures the results in breakdown voltage improvements of the invention have been empirically determined and show, for the first indicated gate structure an improvement in gate breakdown voltage of the invention of approximately 4.5% for NMOS devices and 6.7% for PMOS devices. The improvements of the invention obtained for the second indicated structure is approximately 8.5% for NMOS devices and 5.6% for PMOS devices. These measurement results clearly indicate that the process of the invention achieves the objective of improving the breakdown voltage of the typical PMOS and NMOS gate electrode.
Although the invention has been described and illustrated with reference to specific illustrative embodiments thereof, it is not intended that the invention be limited to those illustrative embodiments. Those skilled in the art will recognize that variations and modifications can be made without departing from the spirit of the invention. It is therefore intended to include within the invention all such variations and modifications which fall within the scope of the appended claims and equivalents thereof. | A new process is provided whereby LDD regions for HV CMOS devices and for LV CMOS devices are created using one processing sequence. The gate electrodes for both the High Voltage and the Low Voltage devices are created on the surface of a silicon substrate. The High Voltage LDD (HVLDD) is performed self-aligned with the HV CMOS gate electrode, a gate anneal is performed for both the HV and the LV CMOS devices. The Low Voltage LDD (LVLDD) is performed self-aligned with the LV CMOS gate electrodes. The gate electrodes of the CMOS devices are after this completed with the formation of the gate spacers, the source/drain implants and the back-end processing that is required for CMOS devices. | 7 |
FIELD OF THE INVENTION
This invention relates to the field of encoding position along a straight-line path and more specifically to encoding position by means of lenticular screens in a direction perpendicular to the axes of the lenticules, and in the planes of the screens.
BACKGROUND OF THE INVENTION
There are several methods of encoding linear position. In one method, a cable attached to a movable platform is wound around a shaft, which is attached to an encoder of rotary motion. In another, a movable platform is attached to a nut threaded with a lead screw which is attached to a rotary encoder. A variation of this method is to move the platform by a stepper motor and keep count of the steps. Coarser encoding can be accomplished by electrical switches located at known positions which are opened and closed in turn by contact with a projection extending from a movable platform. Similarly, a beam of light, infrared, or other radiation can trigger radiation sensors in turn as the platform moves along a linear path. Although the combinations of lead screw and rotary encoder, or lead screw and stepper motor yield high accuracy, resolution, and repeatability, these methods are costly. Conversely, a series of switches or radiation detectors is economical but does not give very high positional resolution.
Sheets of optically transparent lenticular material are sometimes used for producing three-dimensional depth visualization effects and minor animation effects. In order to achieve these effects, it is necessary that the position on the lenticular material be precisely known in order to provide the depth visualization and animation effects. It is extremely complicated and subject to a high risk of error to manually align the lenticular print material for printing.
PRIOR ART
U.S. Pat. No. 5,424,553 (Morton) discloses several methods for aligning lenticular materials for printing. This alignment is essential prior to the lenticular material passing through a printing press for printing a 3D image on the lenticular material. One of his methods is to direct a light beam so that one of the lenticules focuses the light at the printing surface of the lenticular material. A light sensitive array can be used to determine the location so that the lenticular material can be adjusted to the proper location for printing. A computer can be used to determine the position of the sensor in the array which receives the maximum amount of light. Morton discloses another technique for the alignment of the lenticular material using a second piece of lenticular material of a slightly different pitch. The lenticular material to be aligned is illuminated with the other lenticular material with their planar surfaces being adjacent. This results in forming a Moire pattern with the lenticular material being aligned at the position where the local intensity is at its maximum. As shown in FIG. 3 of Morton, the curved surfaces of these sheets of lenticular material face in opposite directions.
U.S. Pat. No. 5,689,340 (Young) discloses an apparatus and method for aligning lenticular material by determining the location of an encoded portion adjacent to the lenticules. A light source illuminates the encoded portion and a sensor determines its precise location for subsequent printing.
U.S. Pat. No. 5,699,190 (Young et al.) discloses lenticular print material having an encoded portion for the alignment and registration of the print material. A portion of the lenticular material adjoining the main portion is encoded to provide the alignment and registration of the main portion. This alignment is achieved by machining an encoded lenticular pattern into the portion that is used for alignment of the main portion.
SUMMARY OF THE INVENTION
The present invention provides a method and apparatus for determining and encoding linear position by means of positional measurements of a collimated beam of radiation passing through two parallel sheets of lenticular material of similar pitch. Linear position can be taken to be the displacement in units of lenticules and fractions thereof of one of the sheets relative to the other from some starting position, in a direction parallel to the sheets and perpendicular to the longitudinal axes of the lenticules. The positional measurements can be made with a multi-element radiation sensor large enough to subtend the field-of-view of the lenticules and located so as to intercept the collimated beam of radiation exiting from the last lenticular sheet. The source of radiation, detector of radiation, and one of the lenticular sheets are held fixed relative to each other, and the other sheet is allowed to move. The fixed sheet is known as the reference sheet and need only be somewhat larger than the diameter of the radiation beam. The length of the movable sheet will determine the span of distance that can be measured by this method. The perpendicular separation of the sheets is held constant and at a distance so that the exiting beam of radiation is recollimated after passing through both sheets. Either the convex or plane surface of each sheet may face the incident radiation beam, with the separation of the sheets depending on the actual configuration. The sensor array is used to determine where within the field-of-view the collimated beam is located, and if the beam has split, where the two beams are located. An accounting of the number of times, and fraction thereof, that the beam has transited the central plane in each direction can be accomplished with a microcontroller which accepts and interprets the output of the sensor array. Each transit corresponds to a linear displacement of one lenticule width, with the displacement resolution depending on the number of detector elements within the field-of-view provided that the collimated beam is not greatly oversampled. The microcontroller can also send this linear position to a display device. This position is encoded which can be in the memory of the microcontroller or by marking the lenticular screen, or otherwise. Because an apparatus based on this invention allows the position of any point on the movable lenticular material relative to some reference point to be determined, one can use such an apparatus to measure distance traversed by a movable table from some starting position, to align an external tool or print head to the lenticular material, or conversely to align the lenticular material to a tool or print head.
It is an objective of the present invention to provide a method and apparatus for accurately encoding linear position with high signal-to-noise ratio (e.g., recollimated radiation to stray radiation ratio).
It is an objective of the present invention to provide a method whereby an inexpensive and compact apparatus can be constructed for encoding linear position.
It is yet another objective of the present invention to provide a method and apparatus for accurately aligning lenticular material to some predetermined position.
It is yet another objective of the present invention to provide a method and apparatus for accurately aligning an external object such as an engraving tool or print head to a predetermined position on lenticular material.
It is still another objective of the present invention to provide a method and apparatus for accurately encoding rotational position wherein one end of the lenticular linear encoder is attached to a cable wound around a shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrate the recollimation of a beam of radiation when both lenticular sheets present their plane ides to the incoming radiation.
FIG. 2 illustrates the recollimation and deflection of a beam of radiation when both lenticular sheets present their plane sides to the incoming radiation and the relative lateral offset between sheets is about one-quarter lenticule or 90 degrees of phase.
FIG. 3 illustrates the recollimation, deflection, and splitting of a beam of radiation when both lenticular sheets present their plane sides to the incoming radiation and the relative lateral offset between sheets is about one-half lenticule or 180 degrees of phase.
FIG. 4 illustrates the recollimation and deflection of a beam of radiation when the both lenticular sheets presents their convex sides to the incoming radiation and the relative lateral offset between sheets is about one-quarter lenticule or 90 degrees of phase.
FIG. 5 illustrates the recollimation and deflection of a beam of radiation when the first lenticular sheet presents its plane side and the second lenticular sheet presents its convex side to the incoming radiation and the relative lateral offset between sheets is about one-quarter lenticule or 90 degrees of phase.
FIG. 6 illustrates the recollimation and deflection of a beam of radiation when the first lenticular sheet presents its convex side and the second lenticular sheet presents its plane side to the incoming radiation and the relative lateral offset between sheets is about one-quarter lenticule or 90 degrees of phase.
FIG. 7 is a schematic illustration of a linear lenticular encoder in which both lenticular sheets present their plane sides to the incoming radiation and the movable sheet is constrained by rollers.
FIG. 8 is a schematic illustration of a linear lenticular encoder in which both lenticular sheets present their plane sides to the incoming radiation and the movable sheet is not constrained as to its direction of travel.
DETAILED DESCRIPTION OF THE INVENTION
When a collimated beam of radiation passes through a lenticular sheet, the beam will ultimately diverge. If a small lens of diameter equal to the width of a lenticule is placed on the optical axis of a single lenticule, a position can be found at which the rays of the beam passing through that lenticule will be recollimated and become available for sensing. However if the beam illuminates more than one lenticule on the sheet, those rays passing through the extra lenticules will not be collimated and will act to reduce the signal-to-noise ratio. If on the other hand only a single lenticule is illuminated by the beam in order to reduce the background, then only a small amount of radiation is available to work with, and furthermore, the lens is restricted to locations within the field-of-view of that lenticule. A much more favorable configuration arises when two parallel lenticular sheets of similar pitch are placed with their longitudinal axes parallel and with a spacing such as to allow recollimation of the incident beam. This is illustrated in FIG. 1, where rays 1 comprising part of a perpendicularly incident collimated beam of radiation are focused by a plurality of lenticules contained on lenticular sheet 2 onto the principal focal plane of sheet 2. Because the plane surface P of lenticular sheet 3 is located approximately in the principal focal planes of both sheets, the rays passing through and exiting the plurality of lenticules on sheet 3 are recollimated. It will be understood that the signal-to-noise ratio is high in this configuration because many lenticules are illuminated and because all the rays are recollimated.
FIG. 2 illustrates the deflection and recollimation of the beam when the lenticular screens are displaced laterally relative to each other by about one-quarter of the width of a lenticule or 90 degrees of phase. Rays 4, which comprise part of a perpendicularly incident collimated beam of radiation are focused by a plurality of lenticules contained on lenticular sheet 5. Lenticular sheet 6, located with its plane surface P in the focal plane of the rays passing through sheet 5, recollimates the rays but deflects them in the direction of its displacement relative to sheet 5 by about one-quarter the field-of-view. It will be understood that the angular deflection of the rays varies continuously from zero to one-quarter the field-of-view as the lateral displacement is continuously varied from zero to 90 degrees of phase.
FIG. 3 illustrates the deflection and recollimation of the beam when the lenticular screens are displaced laterally relative to each other by about one-half of the width of a lenticule or 180 degrees of phase. It will be noticed in FIG. 3 that rays 7 passing through sheet 8 are focused onto the focal plane at plane P of sheet 9 as in the case of FIGS. 1 and 2. In other words, the distance between the sheets in FIGS. 1-3 is the same. Rays 7, which comprise part of a perpendicularly incident collimated beam of radiation are focused by a plurality of lenticules contained on lenticular sheet 8. Lenticular sheet 9 located with its plane surface P in the focal plane of the rays, recollimates the rays but splits them, deflecting about one-half of them in the direction of its displacement relative to sheet 8, and about one-half of them in the opposite direction, each by about one-half the field-of-view. It will be understood that the angular deflection of the rays varies continuously from one-quarter the field-of-view to one-half the field-of-view as the lateral displacement is continuously varied from 90 to 180 degrees of phase. It will also be understood that as the lateral displacement is continuously varied from 180 to 360 degrees of phase, the beam deflected by one-half the field-of-view in the direction of displacement of sheet 9 will pass out of the field-of-view and disappear, and that the beam deflected in the opposite direction will vary continuously from a deflection of one-half the field-of-view to zero.
It will be understood that if instead of keeping the radiation beam and first screen fixed, and displacing the second screen, the radiation beam and second screen are fixed and the first screen is displaced, then the collimated beam deflects in a direction opposite to the displacement of the first screen. It will also be understood that the second lenticular sheet 3, 6, or 9 can be displaced laterally by multiples of the width of a lenticule, or displaced along the longitudinal axes of the lenticules without any change in the direction of the collimated beam.
It is important in conducting these measurements that the longitudinal axes of the lenticules in the first and second screens be substantially parallel to each other.
For each additional relative displacement of the screens by one lenticule, or 360 degrees of phase, the beam's deflection proceeds from zero to its maximum angle, at which point it has split into two beams, following which, the newly appeared beam's deflection proceeds from the maximum angle toward zero. By counting the number of times that the deflection of the beam passes through zero in a given direction, one has a measure of the displacement of the screens relative to each other in units of the width of a lenticule. Improved resolution, to a fraction of width of a lenticule, is accomplished by measuring the deflection of the beam as a fraction of the field-of-view. Both the count of zero crossings and measurement of deflection can be accomplished with a detector array whose output is read and processed by a microcontroller, microprocessor or computer. The result can be sent from the microcontroller to a display.
The linear position can be encoded for future reference. The position can be encoded in an electronic memory device such as a computer memory or directed to a display device, recording device, hard copy device, warning device, tool, or print head. The position can be encoded in terms of x and y coordinates of the position. Also, a hard copy of the encoding can be made. Alternatively, the linear position can be physically encoded on the lenticular sheet by marking, which includes making a reference cut. It will be understood that if any object bears a known or calculable position relative to either sheet, then an encoding of its linear position is implied by the encoding of the relative linear position of the screens. The term "encoding" refers to all of these methods of retaining the linear position which have been determined by this invention.
It will be understood that the resolution obtainable by this method of encoding position depends on the number of detector resolution elements within the field-of-view provided that the beam is not greatly oversampled. It will be understood that the resolution will also depend on how many bits are used to encode the output from the detector array.
Many algorithms, such as centroiding, thresholding and averaging, or maximum value can be used by the microcontroller to determine the beam's position. A preferred algorithm for a linear detector with n elements indexed from 0 to n-1 subtending the field-of-view of the lenticular material from left to right and having outputs D i , consists of initially thresholding each element output by setting that output to zero unless D i is greater than some threshold T. A suitable threshold could be 1/5 of the expected maximum value. Next, in order to determine whether there are two spots, which occurs near 180 degrees of phase, the quantities ##EQU1## are calculated. If both are zero, the spot is near the center of the array; if both are nonzero, the spot is near 180 degrees of phase; and if only one is nonzero, the spot is near either the left or right ends. A centroid calculation can next be used to obtain the position of the spot. When the spot is near the center, the position in units of detector elements is ##EQU2## When the spot is near 180 degrees the larger of S L and S R can be used to determine which two quadrants to perform the above centroid calculation in, i.e., i=n/2 to i=n for S L <S R and i=0 to i=n/2 for S L >S R . If S L =S R the spot is exactly at 180 degrees. If only one of S L and S R are nonzero, the centroid calculation is performed in either the left or right halves of the detector, respectively. The processor continually monitors the value of x and must keep track of how many times the beam has crossed the center of the field-of-view, x c =n/2, in a given direction. If the previous value of x is x p and the number of times that the beam has crossed x c from left to right from some starting position is N, then N is incremented by 1 if (x≧n/2 and x p <n/2 and (x-x p )<n/2). Also, N is decremented by 1 if (x<n/2 and x p >n/2 and (x p -x)<n/2). Finally, the displacement of the lenticular screens relative to each other and relative to some starting position in units of the width of a lenticule can be expressed as X=N+(x-n/2)/n.
The method described above uses two lenticular screens, with one fixed relative to the radiation source and the other movable. The fixed one can be called the reference screen and need not be much larger than the width of the radiation beam. The length of the movable screen determines the span of length that can be encoded. Screens of more than 40 inches have been encoded. In the configuration of screens shown in FIGS. 1, 2, and 3, both screens present their plane faces P towards the incident radiation beam, but either the convex or plane face of either or both screens can face the incident beam.
FIG. 4 illustrates the deflection and recollimation of the beam when both screens present their convex faces towards the incident beam and the lenticular screens are displaced laterally relative to each other by about one-quarter of the width of a lenticule or 90 degrees of phase. Rays 10, which comprise part of a perpendicularly incident collimated beam of radiation, are focused onto the principal focal plane of lenticular sheet 11, which is approximately coincident with the plane surface P of lenticular sheet 11. Lenticular sheet 12 located with its principal focal plane approximately coincident with the principal focal plane surface of sheet 11, recollimates the rays but deflects them in the direction of its displacement relative to sheet 11 by about one-quarter the field-of-view.
FIG. 5 illustrates the deflection and recollimation of the beam when the first screen 14 presents its plane face P and the second screen presents its convex face towards the incident beam and the lenticular screens are displaced laterally relative to each other by about one-quarter of the width of a lenticule or 90 degrees of phase. Rays 13, which comprise part of a perpendicular incident collimated beam of radiation are focused onto the principal focal plane FP of lenticular sheet 14. Lenticular sheet 15 located with its principal focal plane FP approximately coincident with the principal focal plane surface of sheet 14, recollimates the rays but deflects them in the direction of its displacement relative to sheet 14 by about one-quarter the field-of-view.
FIG. 6 illustrates the deflection and recollimation of the beam when the first screen presents its convex face and the second screen presents its plane face towards the incident beam and the lenticular screens are displaced laterally relative to each other by about one-quarter of the width of a lenticule or 90 degrees of phase. Rays 16, which comprise part of a perpendicular collimated beam of radiation are focused onto the principal focal plane of lenticular sheet 17, which is approximately coincident with the plane surface P of lenticular sheet 17. Lenticular sheet 18 located with its principal focal plane approximately coincident with the principal focal plane and plane surface P of sheet 17, recollimates the rays but deflects them in the direction of its displacement relative to sheet 17 by about one-quarter the field-of-view.
It will be understood that the configuration shown in FIG. 5 permits the widest gap between the lenticular sheets and that the configuration shown in FIG. 6 yields the smallest gap between the lenticular sheets. It will be understood that the construction of a workable encoder based on the configuration of FIG. 6 may require using a lubricating film between the sheets or the manufacture of sheets of slightly thinner dimensions so that the principal focal planes lie outside the material. It will also be understood that some configurations of the lenticular sheets will suffer less from spherical and other types of aberrations, and that the surface curvature can be optimized during manufacture to minimize such aberrations.
An embodiment for practicing the method of this invention is shown in FIG. 7. Numeral 19 indicates a source of collimated radiation which can be a laser, which provides a substantially parallel beam of rays 20 to illuminate a plurality of lenticules on lenticular screen 21. Both the planar surface of screen 21 and screen 22 present their plane sides P to the incoming radiation. Screen 21 is the reference screen; the relationships between the reference screen 21 and the lenticular screen 22, which is to be encoded, are illustrated in FIGS. 1, 2 and 3. Screens 21 and 22 are spaced apart in accordance with the principle discussed in connection with the description of FIG. 1. Rays 20 enter the plane surface P of the screen 21, are brought to a focus in the principal focal plane of the screen, and illuminate lenticular screen 22 which is located in a plane substantially parallel to screen 21, oriented with its longitudinal axes substantially parallel to those of screen 21, spaced so that its plane surface P is substantially in the principal focal plane of screen 21, and has a pitch similar to that of screen 21. The rays are recollimated by screen 22 and are detected by detector array 27, which can be a linear or one-dimensional detector. The output from the detector is fed to microcontroller 28 where it is processed to determine the location of the beam within the field-of-view of the lenticules, and to keep count of the number of transits and fractions thereof of the center of the field-of-view by the beam as sheet 22 moves horizontally in the figure. Microcontroller 28 can display the accumulated count of transits and fractions of transits in units of lenticules or other units on the display device 29 or the position can also be encoded in the microcontroller's memory. Lenticular sheet 22 can be held in its proper orientation and spacing relative to sheet 21 and constrained in its direction of travel by guides 23, 24, 25, and 26 which can be rollers. Guides 30 and 31 hold the reference lenticular sheet 21 in proper position to encode sheet 22. Sheet 22 can be encoded with a mark for future reference. Table 32 is attached to the rollers 23, 24, 25 and 26 and can be adjusted up and down in order to place reference lenticular reference sheet 21 in proper position with the lenticular sheet 22.
In another embodiment of the present invention, lenticular screen 21 can present its convex side to illuminating beam 20 and lenticular screen 22 can present its convex side to the beam, as diagrammed in FIG. 4.
In one embodiment of the present invention, lenticular screen 21 can present its plane side P to illuminating beam 20 and lenticular screen 22 can present its convex side to the beam, as diagrammed in FIG. 5.
In another embodiment of the present invention, lenticular screen 21 can present its convex side to illuminating beam 20 and lenticular screen 22 can present its plane side P to the beam, as diagrammed in FIG. 6.
The above embodiments for practicing this invention show the beam of rays, reference screen, and detector array fixed, and the screen to be encoded as movable. Other embodiments, such as keeping the screen to be encoded fixed, and the beam, reference screen, and detector array movable, or keeping the reference screen, screen to be encoded, and detector array fixed, and the beam movable, or keeping the reference screen and screen to be encoded fixed, and the beam and detector array movable, are valid alternatives.
The above embodiments directly lend themselves to applications such as encoding the position of an XY mechanical stage or the setting of a caliper, thus yielding digital versions of traditional measuring devices. A digital micrometer can be designed from these embodiments by attaching a cable wound around the micrometer shaft to the movable lenticular sheet, and providing sufficient tension to avoid backlash.
Yet another embodiment of the present invention is shown in FIG. 8. This embodiment is slightly different from that shown in FIG. 7 in that there are no guides to constrain the direction of travel of lenticular sheet 22. The table 32 is held in a fixed position established on the type of method being practiced. However, it should be understood that a mechanism can be provided for adjusting this table 32. This arrangement allows the lenticular sheet to pass through the apparatus in a longitudinal as well as a lateral direction. The positional information in the lateral direction can be used to align a tool or print head or other device to the movable lenticular material, or an object attached to that material, and conversely to align the movable lenticular material or an object attached to that material to a tool or print head or other device.
It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. | A method of determining linear position by means of lenticular screens in a direction perpendicular to the axes of the lenticules and in the planes of the screens is disclosed comprising the steps of:
a) directing a collimated beam of radiation perpendicularly into a first sheet of lenticular material;
b) allowing the beam transmitted by the first sheet to enter a second sheet of similar pitch, oriented parallel to the first sheet, and with the axes of the lenticules parallel to the axes of the first sheet, and spaced so as to recollimate the radiation beam upon exit from the second sheet;
c) placing a radiation detector array situated to receive the collimated beam exiting from the second lenticular sheet and subtending the field-of-view of the lenticules;
d) sensing the position of the collimated beam within the field-of-view of the lenticules, and keeping account of the number of transits and fractions thereof of the beam across the center of the field-of-view of the lenticules with the detector array, due to a displacement of the lenticular sheets relative to each other in a direction perpendicular to the axes of the lenticules and in a plane parallel to themselves. Also disclosed is an apparatus for measuring linear displacement, comprising a device for producing a collimated beam of radiation; a reference lenticular sheet; a movable lenticular sheet; and a detector array. Means for encoding the linear displacement is also disclosed. | 6 |
CROSS-REFERENCES TO RELATED APPLICATIONS
The present invention is related to commonly assigned, concurrently filed and co-pending U.S. application Ser. No. 09/472,731 for “LASER WITH SIMPLIFIED RESONATOR FOR PRODUCING HIGH QUALITY LASER BEAMS”; Ser. No. 09/472,733 for “LASER SYSTEM AND METHOD FOR BEAM ENHANCEMENT”; and Ser. No. 09/472,735 for “LASER ASSEMBLY SYSTEM AND METHOD.” All of the above U.S. Applications are incorporated by reference.
TECHNICAL FIELD
The present invention relates generally to cooling systems for lasers, and more particularly, to a heat transfer system and method for lasers utilizing electrode based excitation.
BACKGROUND OF THE INVENTION
Many types of lasers use electrodes to convey excitation energy to either gaseous or non-gaseous plasmas. For instance, radio frequency excited gas lasers utilizing electrodes have become a mainstay in a wide variety of industrial, medical, and scientific applications. In particular, molecular gas lasers, such as those based on carbon dioxide gas, use electrodes to excite the gas plasma.
As is typical with gas lasers, gas temperature is a determining factor of equipment size, beam quality, and power levels of operation. For example, the maximum acceptable plasma temperature for a carbon dioxide based laser is approximately 600 Kelvin. Generally, for optimal performance of a laser, certain temperature ranges for operation of laser plasma are preferred. During operation, generation of the laser plasma produces much heat. To maintain optimal temperature ranges for the plasma any excess heat must be extracted from the plasma.
In lasers utilizing electrodes, the plasma generally contacts the surfaces of the electrodes. The electrodes, thus, become a possible candidate for removing heat from the plasma. Some conventional lasers utilize electrode surfaces in contact with the plasma for cooling by actively cooling the electrodes using fluid circulating through the electrodes. Circulating fluid through electrodes, however, complicates assembly and operation, and increases overall laser system package size.
Other conventional lasers have recognized the problems of circulating fluid through electrodes. Unfortunately, with these conventional lasers that do not cool the electrodes with fluid, the electrodes serve a rather limited role in removing heat from the plasmas. Consequently, these conventional lasers have limitations regarding operational power levels or have cooling structures apart from the electrodes. These additional cooling structures also increase laser size and expense, or restrict laser operations. For instance, some conventional lasers actively circulate the plasma gases, which increases laser size and cost. Other conventional lasers use structures that provide surfaces other than those of the electrodes for cooling of the plasmas.
These strictures include bores, rods, or discharge side walls, which complicate laser assembly, increase laser size, and limit laser operation. For instance, discharge sidewalls can restrict expansion of the gas plasma so that standing waves of varying gas density occur in the gas plasma. These standing waves introduce limitations for the operation of the laser such as the frequencies at which the laser can be pulsed.
SUMMARY OF THE INVENTION
A laser with heat transfer system and method has aspects including first and second electrodes, a lasing medium, a housing, and first and second portions of thermally conductive and electrically insulating material being other than the lasing medium. The first and second electrodes have an interior surface and an exterior surface. The lasing medium is located between at least portions of the interior surfaces of the first and second electrodes. The housing has opposing first and second walls with first and second interior surfaces, respectively, forming at least a portion of a housing cavity sized to contain the first and second electrodes. The first and second electrodes are positioned inside the housing cavity with the interior surfaces of the first and second electrodes opposingly spaced a part.
The first interior housing surface is spaced from the exterior surface of the first electrode by at least a first distance forming a first volume between the first interior housing surface and the exterior surface of the first electrode. The second interior housing surface is spaced from the exterior surface of the second electrode by at least a second distance forming a second volume between the second interior housing surface and the exterior surface of the second electrode.
The first and second portions of the thermally conductive and electrically insulating material is other than the lasing medium. The first portion of the thermally conductive material is positioned in contact with at least a portion of the first interior housing surface and at least 5% of the exterior surface of the first electrode and occupies a portion of the first volume. The second portion of the thermally conductive material is positioned in contact with at least a portion of the second interior housing surface and at least 5% of the exterior surface of the second electrode and occupies a portion of the second volume.
Further aspects include the thermally conductive material comprising a ceramic. Other aspects include the laser medium filling at least portions of the first and second volumes not occupied by the first and second portions of the thermally conductive materials. In some of these further aspects, the lasing medium is at a pressure less than atmospheric pressure to produce a pressure differential to provide an inwardly directed force on the first and second walls. The first and second walls have sufficient flexibility to flex inward under the inwardly directed force provided by the pressure differential to press the first and second interior surfaces against the first and second portions of the thermally conductive material, respectively.
Additional aspects include the first portion of the thermally conductive material comprising a first plurality of ceramic strips. The external surface of the first electrode being formed with a first plurality of depressions. Each depression of the first plurality of depressions is sized to receive at least one of the first plurality of ceramic strips therein. The second portion of the thermally conductive materials comprising a second plurality of ceramic strips. The external surface of the second electrode is formed with a second plurality of depressions. Each depression of the second plurality of depressions is sized to receive at least one of the second plurality of ceramic strips.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric schematic drawing of a slab laser utilizing an embodiment of the present invention.
FIG. 2 is a schematic drawing of a slab laser utilizing a folded resonator embodiment of the present invention.
FIG. 3 is a longitudinal cross-sectional view of an alternative embodiment of the present invention illustrating use of multiple sets of electrode pairs.
FIG. 4 is a longitudinal cross-sectional view of an alternative embodiment of the present invention illustrating use of contoured electrodes.
FIG. 5 is a longitudinal cross-sectional view of an alternative embodiment of the present invention illustrating use of tapered electrodes.
FIG. 6 is a longitudinal cross-sectional view of an alternative embodiment of the present invention illustrating use of triangularly tapered electrodes.
FIG. 7 is an enlarged, exploded isometric diagram illustrating the electrode assembly of the depicted embodiment of FIG. 1 .
FIG. 8 is an isometric diagram illustrating the electrode assembly of FIG. 7 using inductors.
FIG. 9 is an exploded isometric diagram illustrating the assembly details of the depicted embodiment of the present invention.
FIG. 10 is an enlarged transverse cross-sectional view of the assembled laser taken substantially along the line 10 — 10 of FIG. 9 with alternative inductors used.
FIG. 10A is a detailed view of a portion of FIG. 10 including a thermal strip and a ceramic pill.
FIG. 11A is a transverse cross-sectional view showing bowing of top and bottom walls of the housing of the laser of FIG. 10 .
FIG. 11B is an exaggerated simplified transverse profile of the housing of FIG. 11A overlaid upon a simplified transverse profile of the electrode assembly of FIG. 8 .
FIG. 12 is the transverse profile of the housing overlaid upon the transverse profile of the electrode assembly shown in FIG. 11B showing the housing in a fully expanded position.
FIG. 13 is the transverse profile of the housing overlaid upon the transverse profile of the electrode assembly shown in FIG. 11B showing the housing in an initial relaxed position.
FIG. 14 is the transverse profile of the housing overlaid upon the transverse profile of the electrode assembly shown in FIG. 11B showing the housing in the final relaxed position.
FIG. 15A is a top view of the first electrode of the electrode assembly of FIG. 8 showing thermal strip and ceramic pill placement of an alternative embodiment.
FIG. 15B is a bottom view of the second electrode of the electrode assembly of FIG. 8 showing thermal strip and ceramic pill placement of the alternative embodiment of FIG. 15 A.
FIG. 16 is a transverse cross-sectional view of the electrode assembly of FIG. 8 taken substantially along the line 16 — 16 of FIGS. 15A and 15B showing flexing detail of the top and bottom walls of the housing.
DETAILED DESCRIPTION OF THE INVENTION
As shown in the drawings for purposes of illustration, the present invention is embodied in a narrow gap, or slab, gas laser with a cooling system, sharing some aspects in common with the conventional slab laser generally indicated by reference 1 in FIG. 1 . The conventional slab laser 1 includes first and second elongated planar slab electrodes 12 and 14 parallel to each other and extending between a front resonator mirror 16 and a rear resonator mirror 18 . A gas lasing medium is positioned within an optical resonator cavity 20 formed between the resonator mirrors 16 and 18 . The resonator cavity 20 serves as a discharge area for the gas lasing medium.
In the depicted embodiment, the resonator cavity is rectangularly shaped, however, alternative embodiments have square, annular, or other shaped resonator cavities, such as folded resonator cavities. A slab laser 10 according to the present invention (such as shown in FIGS. 9 and 10) can have a folded resonator in some embodiments that are similar in some aspects to the conventional folded resonator shown in FIG. 2, which in this case has a flat mirror 19 positioned between the front and rear mirrors 16 a and 18 b. Typical with folded cavities, there are multiple resonator sections 20 a and 20 b, as shown in FIG. 2 . Some of the reference numbers in the detailed description are used for parts of both the conventional slab laser 1 and the slab laser according to the present invention 10 . For instance, both the slab laser 1 and the slab laser 10 have first and second electrodes 12 and 14 , however, as evident from the discussion below, the first and second electrodes 12 and 14 of the inventive slab laser 10 may not share all its aspects with conventional electrodes. Other embodiments have other configurations of mirrors and resonator cavities, including more than two resonator sections. For instance, some embodiments use more than one set of electrodes with more than one associated discharge space such as those sets of electrodes shown in FIG. 3 having pairs of first and second electrodes 12 ′, 14 ′, and 12 ″, 14 ″, and 12 ′″, 14 ′″, respectively. Other embodiments utilize contoured first and second electrodes 12 d and 14 d that are non-planar with respect to at least one dimension, for instance the longitudinal z-axis, as shown in FIG. 4 . Further embodiments use tapered first and second electrodes that are planar, but are not parallel with the longitudinal z-axis such as tapered first and second electrodes 12 e and 14 e of FIG. 5 and triangularly tapered first and second electrodes 12 f and 14 f of FIG. 6 . Other configurations for electrodes are used as well.
For the depicted embodiment, the gas lasing medium is a standard mixture of one part carbon dioxide (CO 2 ), one part nitrogen (N 2 ), and three parts helium (He), with the addition of 5% xenon (Xe) at a pressure of 50 Torr. Other embodiments use other gas mixtures, or their isotopes, including portions of neon (Ne), carbon monoxide (CO), hydrogen (H 2 ), krypton (Kr), argon (Ar) or oxygen (O 2 ) and other gases at various other gas pressures, however, it will be appreciated that a non-gaseous lasing medium could also be employed. For instance, an alternative embodiment lasing medium could comprise one or more of the following vapors: copper, gold, strontium, barium, a halide compound of copper, a halide compound of gold, a halide compound of strontium, and a halide compound of barium. Other embodiments use liquids or dyes for their lasing medium.
The slab laser 10 also includes a power supply 21 that applies excitation energy to the gas lasing medium, which causes the lasing medium to emit laser energy. The excitation energy supplied by the power supply 21 in the depicted embodiment has an associated RF voltage, but may also be associated with microwave, pulsed, continuous wave, direct current, or any other voltage that stimulates the lasing medium into producing laser energy. Alternative embodiments utilize other forms of excitation including optically pumped solid-state lasers or use energy sources based upon solar energy, nuclear energy, or chemical energy. When the RF voltage is applied to the gas lasing medium via the slab electrodes 12 and 14 , a gas discharge forms within the resonator cavity 20 between the front and rear mirrors 16 and 18 . The front and rear mirrors 16 and 18 form the laser energy into a laser beam 22 that travels back and forth in a longitudinal direction along a z-axis as shown in FIG. 1 .
In the slab laser 10 , the front and rear mirrors 16 and 18 are shaped and positioned to form an unstable resonator along the x-axis of FIG. 1 with an exit aperture 24 such that the laser beam 22 travels laterally until the laser beam exits the resonator cavity 20 via the exit aperture. The slab laser 10 has what is referred to as an unstable resonator even though its resonator is stable along the y-axis of FIG. 1 since its resonator is unstable along the x-axis. This slab laser 10 is alternatively referred to as a hybrid stable-unstable resonator since it is stable with respect to one axis and unstable with respect to another axis. The slab electrodes 12 and 14 are positioned sufficiently far from each other so that the resonator cavity 20 acts as a free-space resonator along the y-axis with a Fresnel number of approximately 0.9 in the depicted embodiment. The slab electrodes 12 and 14 are sufficiently wide and the resonator cavity 20 has little if any sidewalls so that the laser beam 22 has free space propagation with respect to the x-axis as well. Other embodiments use free-space resonators of other Fresnel numbers. Since the resonator cavity 20 acts as a free-space resonator, no special polishing of the slab electrodes 12 and 14 is required in the manufacturing process. Other embodiments include waveguide resonators and non-hybrid stable or unstable resonators.
The laser beam 22 produced by the slab laser 10 exits the resonator cavity 20 via the exit aperture 24 , as shown in FIG. 1 . In the depicted embodiment, the front and rear mirrors 16 and 18 have opposing concave reflective surfaces. The front and rear mirrors 16 and 18 are also confocal, i.e., have a common focal point. The exit aperture 24 is formed between the resonator walls 12 and 14 by extending the rear mirror 18 beyond an end of the front mirror 16 (along the x-axis of FIG. 1) so that the laser beam 22 is reflected by the rear mirror 18 out of the resonator cavity 20 through the exit aperture 24 . The front mirror 16 and rear mirror 18 in the depicted embodiment are totally reflecting, but in other embodiments the mirrors are partially reflecting.
The first and second electrodes 12 and 14 are shown in a more detailed view of FIGS. 7 and 8 as part of an electrode assembly 25 . The electrode assembly 25 includes depressions 26 in an exterior, outer wall surface 12 a of the first electrode 12 and in an exterior outer wall surface 14 a of the second electrode 14 sized and shaped to receive thermal strips 28 . The depressions and thermal strips for the outer wall surface 14 a of the second electrode 14 are not shown but are substantially identical to those for the first electrode 12 . In other embodiments, one or more aspects of the thermal material used for the first electrode 12 differs from one or more aspects of the thermal material used for the second electrode 14 with those aspects including but not limited to size, shape, type, and number of strips or pieces used. In the depicted embodiment, the thermal strips 28 are made of 1 mm thick alumina (Al 2 O 3 ) ceramic of approximately 96% purity. The thermal strips 28 electrically insulate the first and second electrodes 12 and 14 from a housing 44 within which the electrode assembly 25 is positioned on assembly of the laser 10 , best shown in FIGS. 9 and 10. The thermal strips 28 thermally conduct heat to the housing 44 for cooling of the laser by having external surfaces 28 a of the thermal strips 28 in contact with the housing. The housing 44 of the depicted embodiment is of vacuum type to contain the gas lasing medium and to fully enclose the discharge area of the resonator cavity 20 .
The housing 44 in the depicted embodiment has a rectangular transverse cross-sectional profile; however, housings of other embodiments have other transverse cross-sectional profiles including square, annular and other profiles. Other embodiments use an unsealed housing that allows for a slow flow of purge gas to circulate into and out of the housing, but does not significantly contribute any cooling effects to the first and second electrodes 12 and 14 . Still other embodiments use other types of ceramic, dielectric material, or other electrically insulating material for the thermal strips 28 which is also a thermally conductive material positioned adjacent to the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 . For instance, the following can be used either alone or in various combinations with each other: alumina, beryllia, boron nitride, aluminum nitride, mica, polyimide or other electrically insulating materials having thermally conductive and dielectric properties. For gas lasers, the thermal conducting materials are selected with a thermal conductivity greater than the thermal conductivity of the lasing gas medium used in the lasers. These thermal materials can be formed in various shapes other than flat strips positioned adjacent to the first and second electrodes 12 and 14 and adjacent to the housing 44 by either being press fitted into the depressions 26 as is done in the depicted embodiment or by other methods such as coating and bonding methods, e.g., using flame or plasma spraying or anodizing or other methods known in the art. The coating and bonding methods include coating and bonding either portions of the exterior outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 , respectively, or coating and bonding portions of the interior surfaces of the housing 44 adjacent these exterior outer wall surfaces of the electrodes, or coating and bonding a combination of portions of both interior housing and exterior electrode wall surfaces.
In the depicted embodiment, the electrode assembly 25 further includes ceramic spacers 30 to provide gaps between the first and second electrodes 12 and 14 . Other embodiments use other ways to support the first and second electrodes 12 and 14 to maintain gaps between the electrodes. The first and second electrodes 12 and 14 are fastened together with the ceramic spacers 30 therebetween rising bolts 32 , lock washers 34 , and flat washers 36 . The bolts 32 are threadably received in threaded apertures 37 in the second electrode 14 . The bolts and washers are positioned within ceramic bushings 38 to insulate the first electrode 12 from the second electrode 14 .
The first and second electrodes 12 and 14 further include ceramic pills 40 received in rows of recesses 41 formed in the outer wall surface 12 a of the first electrode 12 and formed in the outer wall surface 14 a of the second electrode 14 to provide physical separation of the first and second electrodes 12 and 14 from the housing 44 with external surfaces 40 a of the ceramic pills 40 being in contact with the housing. The ceramic pills 40 and recesses 41 of the second electrode are not shown in the drawings but are substantially identical to those for the first electrode 12 . The first and second electrodes 12 and 14 can be fabricated from one or a combination of aluminum, copper, brass, stainless steel, gold, silver, platinum or other suitable metals or compounds. The housing 44 in the depicted embodiment is formed from a heat conductive metal alloy, but in other embodiments the housing can be made from other thermally conductive materials.
The slab laser 10 in the depicted embodiment, best illustrated in FIG. 9, includes two end caps 46 positioned at the opposing ends of the housing 44 , and two optic assemblies 48 positioned at the opposing ends of the housing, outward of the corresponding end cap.
The laser 10 is assembled by placing the electrode assembly 25 inside of the housing 44 as shown in FIG. 10, by expanding the housing in the direction shown by arrows, A in FIG. 9 . The housing 44 has sufficiently flexible and resilient top and bottom walls 44 a and 44 b to allow them to be pulled apart sufficiently from an unflexed position to a first flexed position for insertion of the electrode assembly 25 therebetween and then to allow them to move back toward a less flexed second position engaging the electrode assembly and clamping the electrode assembly within the housing. The housing 44 has extended longitudinal ridges 45 integral with the top and bottom walls 44 a and 44 b of the housing to allow a mechanism (not shown) to clamp on to the longitudinal ridges to apply the outward force necessary to expand the top and bottom walls of the housing. In the depicted embodiment, the top and bottom walls 44 a and 44 b of the housing 44 are so formed to provide substantially uniform contact, along the transverse x-axis, with the thermal strips 28 and the ceramic pills 40 when in the second flexed position.
As best shown in FIG. 11A, when in the unflexed position the top and bottom walls 44 a and 44 b of the housing 44 are slightly bowed inward toward the center, C, of the housing in the direction of the transverse y-axis along the transverse x-axis from both first and second sidewalls 44 c and 44 d of the housing 44 toward a center, indicated by letter “C”, of the housing in the direction of the transverse y-axis. For the housing 44 in the unflexed position of the depicted embodiment, the distance, D 1 , between the top and bottom walls 44 a and 44 b of the housing 44 at the center, C, of the housing is 1.671, plus/minus 0.030 inches, whereas the distance, D 2 , that the first and second sidewalls 44 c and 44 d span between the top and bottom walls is 1.757 inches, plus/minus 0.016 inches.
An exaggerated simplified transverse cross-sectional profile of the housing 44 in the unflexed position overlaid upon a simplified transverse cross-sectional profile of the electrode assembly 25 taken along a plane parallel to the x-axis and y-axis is illustrated in FIG. 11B to compare their dimensions. Top and bottom external surfaces 25 a and 25 b of the electrode assembly 25 are defined by the external surfaces 28 a of the thermal strips 28 and/or the external surfaces 40 a of the ceramic pills 40 located adjacent to the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 as shown in FIGS. 8 and 9. Referring to FIG. 11B, the maximum distance, Dm, between the top and bottom external surfaces 25 a and 25 b of the electrode assembly 25 is the distance between the external surfaces 28 a of pairs of the thermal strips 28 and/or the external surfaces 40 a of pairs of the ceramic pills 40 located at corresponding positions on opposing sides of the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 .
In the depicted embodiment, in the unflexed position, the interior surface of the top and bottom walls 44 a and 44 b of the housing 44 at the center, C, of the housing are closer together by two times Dc (Dc being 0.010 to 0.050 inches in the depicted embodiment) than the maximum distance, Dm, between top and bottom external surfaces 25 a and 25 b of the electrode assembly 25 . The interior surfaces of the top and bottom walls 44 a and 44 b of the housing 44 at first and second sidewalls 25 c and 25 d of the electrode assembly 25 are closer together by two times De (De being 0.003 to 0.040 inches in the depicted embodiment) than the maximum distance, Dm, between the top and bottom external surfaces 25 a and 25 b of the electrode assembly 25 . In the depicted embodiment, the width, W, along the x-axis of the electrode assembly 25 is 3.7 inches and the distance between the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 is 1.731 inches. The housing 44 is an aluminum extrusion with the top and bottom walls 44 a and 44 b of the housing in the depicted embodiment having an undeformed wall thickness of 0.093 inches and an undeformed wall span, WS, of 6.0 inches.
To allow for insertion of the electrode assembly 25 into the housing 44 , the top and bottom walls 44 a and 44 b of the housing are pulled farther apart in the direction of the arrow A 12 , from the unflexed position of FIG. 11B, another 0.14 inches in the depicted embodiment, into the first flexed position shown in FIG. 12 . The first flexed position allows for a clearance, E, of at least 0.010 inches in the depicted embodiment between the top and bottom external surfaces 25 a and 25 b of the electrode assembly 25 and the interior surfaces of the top and bottom walls 44 a and 44 b of the housing 44 all along the transverse x-axis whereas other embodiments allow for a clearance, E, of at least 0.005 inches.
Once the electrode assembly 25 is fully inserted inside the housing 44 , the top and bottom walls 44 a and 44 b of the housing are released and allowed to relax first into a third position with initial contact of the top and bottom walls of the housing being made with the top and bottom external surfaces 25 a and 25 b of the electrode assembly at the first and second sidewalls 25 c and 25 d of the electrode assembly. In this third position, at a transverse center, G, a clearance, I, exists between the top external surface 25 a of the electrode assembly 25 and the interior surface of the top wall 44 a of the housing, and the clearance, I, also exists between the bottom external surface 25 b of the electrode assembly and the interior surface of the bottom wall 44 b of the housing. The clearance, I, in the depicted embodiment is less than or equal to 0.007 inches.
If a conventional substantially rigid housing were used, the third position shown in FIG. 13 would be the final position the housing would assume when making contact with components such as electrodes. However, in the present invention, the housing 44 is sufficiently flexible to allow for continued relaxation of the housing onto the electrode assembly 25 . As shown in FIG. 14, the top and bottom walls 44 a and 44 b of the housing 44 are flexible enough to further move inward as they relax sufficiently to make contact with the top and bottom external surfaces 25 a and 25 b of the electrode assembly 25 along substantially the entire width of the electrode assembly along the transverse x-axis. FIG. 16 is a more detailed cross-sectional view taken substantially along the line 16 — 16 of FIGS. 15A and 15B showing the extent of contact between the interior surfaces of the top and bottom walls 44 a and 44 b of the housing 44 with the top and bottom external surfaces 25 a and 25 b of the electrode assembly 25 . As shown in FIG. 16, the top and bottom walls 44 a and 44 b of the housing 44 are flexible enough to contact the external surfaces 28 a of the thermal strips 28 and the external surfaces 40 a of the ceramic pills 40 , but yet are inflexible enough to prevent the interior surfaces of the top and bottom walls of the housing from contacting the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 .
Once the end caps 46 and the optic assemblies 48 are attached to the housing 44 , a lasing gas mixture is introduced into the housing at a pressure below atmospheric. In the depicted embodiment, the housing 44 has sufficient flexibility to flex so that the differential pressure between the gas inside the housing and the external atmosphere causes the top and bottom walls 44 a and 44 b to further clamp the electrode assembly 25 to assure that the internal surfaces of the housing top and bottom walls 44 a and 44 b are pressed into contact with the thermal strips 28 of the first and second electrodes 12 and 14 for better thermal contact of the housing with the thermal strips to better transfer heat to the housing. The dimensions of the housing 44 and the electrode assembly 25 , including the thermal strips 28 , are selected to insure good thermal contact between the housing and the thermal strips of the first and second electrodes 12 and 14 .
Cooling of the electrode assembly 25 is partially accomplished via heat conduction through the gas mixture to the top and bottom walls 44 a and 44 b of the housing 44 . This cooling is dramatically increased by the use of the thermal strips 28 , or other suitable thermally conductive, but electrically insulating material, between each of the first and second electrodes 12 and 14 and the housing 44 . Use of the thermal strips 28 removes a substantial portion of the gap between the first and second electrodes 12 and 14 and the housing 44 in which the gas resides. This gas gap has a significantly lower thermal conductivity that typically reduces cooling of the electrode assembly 25 , but with the present invention is eliminated over a substantial portion of the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 . The thermal strips 28 effectively contribute to cooling of the first and second electrodes 12 and 14 so that cooling fluid need not be circulated through any type of interior chamber for the electrodes.
The number, thickness and surface size of the thermal strips 28 , the type of dielectric or other material used for the thermal strips, and the location and spacing of the thermal strips are factors involved in optimizing the amount of heat conduction from the electrode assembly 25 to the housing 44 for cooling of the laser 10 . In the depicted embodiment, the alumina ceramic chosen for the thermal strips 28 has a favorable mix of thermal conductivity for adequate conduction of heat away from the electrode assembly 25 and appropriate dielectric constant to control discharge breakdown of the lasing plasma. The thermal strips 28 of the present invention are to be distinguished from the prior art electrically insulating ceramic pills whose small size typically on the order of 1% of the electrode surface area is solely to electrically isolate electrodes from a housing.
The chosen alumina ceramic also has an appropriate amount of flexure strength to avoid possible breakage during placement of the electrode assembly 25 into the housing 44 . In the depicted embodiment, the 1 mm thickness of the thermal strips 28 is as thin as practicable without unreasonably increasing the risk of breakage during assembly or use. As noted above, the flexibility of the housing walls 44 a and 44 b combined with a pressure differential existing between the gas mixture inside of the housing 44 and the atmosphere, insures that contact is established and maintained between the housing 44 and the thermal strips 28 in the depicted embodiment. Alternative embodiments use clamps or other support structures to maintain good contact between the thermal strips 28 and the housing 44 .
Use of the thermal strips 28 dramatically improves long-term performance and power stability of lasers, and in particular, air cooled lasers. For instance, experiments indicate a direct correlation between the amount of ceramic used for the thermal strips 28 and improvement in steady state output power level of a laser. For the depicted embodiment, the addition of 1 mm thick alumina ceramic thermal strips 28 with a collective surface size equivalent to 30% of the surface area of the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 shows an improvement of the steady state output power of the slab laser 10 by a factor of two or more with a decrease in the thermal resistance by nearly two orders of magnitude. A top profile of the electrode assembly 25 shown in FIGS. 15A and 15B best illustrates the layout of the thermal strips 28 and the ceramic pills 40 used in the depicted embodiment with the first electrode 12 shown in FIG. 15 A and the second electrode 14 shown in FIG. 15 B.
For the embodiment of the first electrode 12 depicted in FIG. 15 A and the second electrode depicted in FIG. 15B, the thermal strips are 0.520 inches wide and 3.020 inches long. The depressions 26 into the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 are 0.025 inches deep. The thermal strips are 0.040 inches thick so extend 0.015 inches past the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 .
The thermal strips 28 are positioned a distance, K, of 0.945 inches along the transverse x-axis from the longitudinal edge, 12 a 1 and 14 a, 1 of the first and second electrodes 12 and 14 . The thermal strips 28 are spaced apart from each other a distance, L, of 0.125 inches along the transverse x-axis and a distance, M, of 0.105 inches along the longitudinal z-axis except for a distance, N, of 0.50 inches along the longitudinal z-axis at the longitudinal center, O, of the first and second electrodes as shown in FIGS. 15A and 15B.
The ceramic pills 40 are 0.25 inches in diameter. The centers of one set of ceramic pills 40 are spaced a distance, P, of 2.917 inches along the longitudinal z-axis from the longitudinal center, O, and the centers of another set of ceramic pills 40 are spaced a distance, Q, of 8.750 inches along the longitudinal z-axis from the longitudinal center, O. The centers of the ceramic pills 40 are spaced from the longitudinal edges 12 a 1 and 14 a 1 of the first and second electrodes a distance, R, of 0.350 inches.
Another consequence is that the equilibrium operating temperature of the first and second electrodes 12 and 14 is reduced from 95° C. to 45° C. Coverage up to 100% of the surface area of the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 are used in alternative embodiments, however, some configurations of lasers require less than 100% surface area coverage to maximize heat transfer from the first and second electrodes 12 and 14 .
In other embodiments, coverage of at least 5% of the surface area of the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 increases the steady state stable output power of the slab laser 10 by approximately 20%, which is a minimum heat transfer effect to justify the heat transfer system. Other embodiments utilize a surface area coverage of 15% or more resulting in over a 50% gain in steady state stable output power, which is a more commercially desirable result.
Using alumina ceramic in the depicted embodiment for the thermal strips 28 also increases electrical capacitance between the electrode assembly 25 and the housing 44 . This increase in capacitance in turn reduces the unlit gas to lit gas discharge frequency shift, which makes the discharge of the lasing medium easier to initiate. The additional capacitance increases the quality factor ratio of electrical energy that can be stored versus that amount of electrical energy that is dissipated with respect to the physics involved with the electrode assembly 25 . This increase in the quality factor ratio in turn results in a larger voltage across the first and second electrodes 12 and 14 , and consequently, easier ignition of the discharge.
Modeling of the discharge physics involved with the depicted embodiment indicates that the 30% coverage of the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 with the 1 mm thick alumina ceramic increases the capacitance between the electrode assembly 25 and the housing 44 by 68% with a corresponding reduction in unlit to lit resonance frequency shift by 38%, which makes the plasma discharge significantly easier to initiate. Similar modeling indicates that a 100% coverage of the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 with 1 mm thick alumina ceramic increases the capacitance between the electrode assembly 25 and the housing 44 by 227% with a reduction in frequency shift of 66%.
From the advantages gained by 100% coverage, one may conclude that this would be an ideal solution for cooling. There are, however, diminishing returns in adding more thermal strips 28 beyond the point at which the thermal conductivity is sufficient to accomplish adequate removal of heat from the first and second electrodes 12 and 14 , and consequently, adequate removal of heat from the plasma to provide acceptable laser performance. There is a point at which the amount of capacitance between the electrode assembly 25 and the housing 44 becomes too much and starts to significantly distort the electric field and voltage distribution between the first and second electrodes 12 and 14 over the entire length of the electrodes. It is generally agreed that optimum laser performance is achieved if the longitudinal voltage non-uniformity between the first and second electrodes 12 and 14 is less than about 5 to 10%. Transmission line modeling suggests that the inclusion of up to 30% alumina ceramic, as found in the depicted embodiment, will still satisfy this voltage uniformity criterion. For the depicted embodiment, 30% coverage of alumina ceramic provides sufficient cooling to maintain the desired performance of the slab laser 10 .
For the depicted embodiment, the plasma discharge is electrically excited by a radio frequency generator of the power supply 21 applied via a matching network directly to the first and second electrodes 12 and 14 . The RF frequency generator of the power supply 21 operates at a frequency of 40.68 MHz with an output power level of at least 1 kW, but other embodiments operate at other frequencies and power levels. The generator of the power supply 21 is connected to the first and second electrodes 12 and 14 in a biphase fashion such that the phase of the voltage on one electrode is shifted substantially 180 degrees relative to the voltage on the other electrode to achieve a biphase excitation. This phase shift is accomplished by placement of inductors 42 between the first and second electrodes 12 and 14 as shown in FIG. 8 .
Other embodiments use higher coverage by the thermal strips 28 and use of thermal material in other shapes with higher coverage of the first and second electrodes than the 30% coverage by the alumina ceramic thermal strips of the depicted embodiment. For these embodiments using higher coverage levels, inductors 52 are placed between each of the first and second electrodes 12 and 14 and the housing 44 as illustrated in FIG. 10 . Coverage values as high as 100% of the outer wall surfaces 12 a and 14 a of the first and second electrodes 12 and 14 are used in alternative embodiments; however, sufficient inductance values are used for the inductors 52 to balance the capacitance introduced by the use of the additional thermal material to maintain uniformity of the voltage and electric field between the first and second electrodes 12 and 14 .
As shown in FIG. 10, the housing 44 can be formed with grooves 50 on the outward side of its top and bottom walls 44 a and 44 b of the housing to receive cooling tubes (not shown), to accommodate operation of the slab laser 10 at high power levels. The housing 44 can also have cooling fins or other forms of heat sinks to assist in removing heat from the housing and other appendages including mounting brackets.
From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for the purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims. | A laser with a heat transfer system and method of making the same using electrodes. The heat transfer system draws heat from the electrodes which have internal electrode surfaces adjacent to a lasing medium of the laser. Cooling of the electrodes helps to maintain proper operating temperature for the lasing medium. The heat transfer system utilizes thermally conductive material positioned between external surfaces of the electrodes and internal surfaces of a housing that contains the electrodes and the lasing medium. Since the thermally conductive material adds capacitance to the laser system, inductance may be added for compensation depending upon the amount of thermally conductive material used. Options exist for positioning and applying the thermally conductive material between the electrodes and housing including press fitting strips of the thermally conductive material in depressions in the electrodes, and spray coating the thermally conductive material onto the electrodes, or the housing, or onto both the electrodes and the housing. | 7 |
RELATED APPLICATIONS
This Application is a Divisional application of U.S. patent application Ser. No. 13/495,891 filed on Jun. 13, 2012 incorporated herein by reference. Application Ser. No. 13/495,891 claims priority benefit of U.S. Ser. No. 61/496,449, filed Jun. 13, 2011 also incorporated herein by reference.
BACKGROUND OF THE DISCLOSURE
Field of the Disclosure
This disclosure relates to the field of holders for the storage of hair care appliances and similar articles wherein the haircare appliances are stored (held) for immediate use.
SUMMARY OF THE DISCLOSURE
Disclosed herein is an appliance holder for hair care appliances with several novel components. The holder comprising: a base which in turn comprises a support surface, an upright portion extending from the support surface, the upright portion defining a support panel; a plurality of appliance holding tubes removably attached to the support surface; and a wall attachment system whereupon the base may be selectively attached to a vertical surface, or may alternatively rest upon a horizontal surface and wherein the appliance holding tubes are operable in either configuration.
The hair appliance holder as disclosed above may further comprise a clip removably attached to the support surface and offset from an adjacent hair appliance holding tube to provide a thermal barrier between the adjacent hair appliance tube and the clip.
The hair appliance holder may also be formed wherein the clip portion further comprises a plurality of wings extending from the clip portion and formed to maintain a heating element portion of a flat iron in thermal isolation from a heating element portion of the flat iron.
The hair appliance holder may further comprise: a hair dryer holding hook removably attached to the support surface. The hair dryer holding hook may further comprising a first arm and a second arm, with a gap provided between distal ends of the first and second arms to allow lateral passage of an exhaust port of the hair dryer. Lateral herein being a direction orthogonal to the major axis of the exhaust portion of the hair dryer.
The hair appliance holder may be arranged wherein the distal end of the first arm of the hair dryer hook is horizontally forward of the distal end of the second arm such that a net distance between the distal end of the second arm and the distal end of the first arm is greater than a vertical offset between the distal end of the second arm and the distal end of the first arm.
The hair care appliance holder may further comprise at least one malleable pad on the first arm and/or the second arm to reduce scratching and other damage, as well at to maintain the hair care appliance within the hook.
A hair dryer holding hook itself is also disclosed as novel in an of itself. The hook in one form comprising: a fastening system for removable attachment of the hair dryer holding hood to a support surface. The independent hook may also comprise a first arm and a second arm with a gap provided between distal ends of the first and second arms to allow lateral passage of an exhaust port of the hair dryer there between.
The hair dryer hook in one embodiment is arranged wherein the distal end of the first arm is horizontally forward of the distal end of the second arm such that a net distance between the distal end of the second arm and the distal end of the first arm is greater than a vertical offset between the distal end of the second arm and the distal end of the first arm.
The hair dryer hook may further comprise at least one malleable pad on the first arm and/or the second arm as previously discussed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front isometric view of a three appliance holder in a tabletop arrangement.
FIG. 2 is a front isometric view of the embodiment of FIG. 1 in a wall-mounted arrangement.
FIG. 3 is a front isometric view of a four appliance holder in a tabletop arrangement.
FIG. 4 is a front isometric view of the embodiment of FIG. 3 in a wall-mounted arrangement.
FIG. 5 is a front isometric view of a six appliance holder in a tabletop arrangement.
FIG. 6 is a front isometric view of the embodiment of FIG. 5 in a wall-mounted arrangement.
FIG. 7 is a side isometric view of the embodiment of FIG. 5 in a table-top arrangement holding two appliances.
FIG. 8 is a front isometric view of the embodiment of FIG. 5 in a wall-mounted arrangement holding two appliances.
FIG. 9 is a rear isometric assembly view of an embodiment for a table top arrangement.
FIG. 10 is a rear isometric assembly view of an embodiment for mounting on a vertical surface.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
While hair appliance holders have been used for some time in barbershops, hair salons, beauty schools, and the home, a hair appliance holder which is adaptable for the particular desired configuration of the user is still desired.
In one form, the appliance holder is especially useful as being adaptable from a tabletop arrangement, to a wall mounted arrangement. In either configuration, the holder does not significantly hinder the use of any workspace.
Looking to FIG. 1 , it can be seen how this embodiment of the modular appliance holding system 20 generally comprises a support 22 . The support in turn comprising a base 24 , bend 26 , upright portion 28 and attachment panel 30 . FIG. 1 further shows one embodiment of the holding system as sitting upon or attached to a horizontal work surface such as a table, workbench, cabinet, or shelf. The embodiment shown in FIG. 2 is substantially identical in these components; however, the base 24 is shown mounted to a vertical surface, such as a wall. In one form this embodiment is secured to the vertical surface by a plurality of fasteners 72 passed through a plurality of voids 32 and then screwed, bolted, riveted, or otherwise fastened to the vertical surface. As such, several of the components including the clip 40 and hook 48 may be attached in a different manner than that shown in FIG. 1 if desired by the user.
Continuing with a description of the components shown in FIG. 1 , the attachment panel 30 comprises a plurality of voids therein such as may be more easily seen in FIGS. 9 and 10 . Through these voids may be passed a fastener 68 to attach to a system of receiving tubes 34 (for example smaller tubes 38 and larger tubes 36 ) and/or other components. In one embodiment, the components each comprise an interior bottom wall comprising a surface defining a threaded void 70 for receiving and fastening of the fasteners 68 . By way of example, a larger tube 36 , may be utilized for curling or flat irons, hot combs, and similar appliances having a substantially large diameter, while a smaller tube 38 may be used for similar appliances having a relatively small diameter. In this disclosure, the term flat iron will be used to represent such appliances.
While tubes of different cross sections such as square, rectangle, triangle, or other geometries may be used, cylindrical tubes have been found to be easily constructed and utilized.
As it is known that it is often not desirous to have a flat iron closed such that the clamp portion is against the element or heating portion. In this disclosure, a clip 40 may be provided as shown in FIG. 1 which may attach to the attachment panel 30 or alternatively directly to a portion of the tube 34 . This clip creates a heat insulating barrier between the clamp 42 and the heating element 44 of a flat iron 46 .
In one form, the clips 40 include a pair of upwardly and outwardly extending wings 68 to maintain the clamp portion of the flat iron in the desired position.
Due to the design of the attachment system of the tubes 34 , clip 40 , hook 48 and other components, the components may be interchanged, or re-arranged as needed. For example, the embodiment shown in FIG. 1 comprises a single small tube 38 and a single large tube 36 . Although the embodiment shown in FIG. 5 utilizes a single larger tube 36 a and a plurality of smaller tubes 38 a - c . It can also be seen how in this embodiment both the larger tube 36 a and the smaller tube 38 b have been fitted with clips 40 a and 40 b.
In addition, FIG. 5 for example shows two slightly different hooks 48 a and 48 b for use on right and left sides of the apparatus. When the apparatus is converted to use on a vertical surface as shown in FIG. 6 , the hooks may be reversed as shown.
Looking to FIGS. 4 and 7 , it can be seen how this arrangement of the modular appliance holding system 20 utilizes a three-tube embodiment with a singular hook 48 for holding of a hair dryer 60 or similar apparatus. As can be seen, this embodiment of the lower portion 50 of the clip 48 attaches to the attachment panel 30 and extends outward to a bend and then extends forward generally in alignment with the tubes 34 . A first engagement arm 52 extends therefrom and may incorporate a pad 54 , such as a nonskid, foam-like portion. A second arm 56 is also utilized in the same manner as the first arm 52 . As can be seen, a gap 58 between the outer edges of the first arm 52 and second arm 56 is large enough to accept the outlet or exhaust portion 62 of a hair dryer 60 (see FIG. 8 ). In some applications, the hair dryer 60 may utilize a diffuser 64 or similar component, which commonly prohibits engagement of the hair dryer into prior holders. Thus, the operator must remove the diffuser before placing the hair dryer into such receivers (holders), or alternatively, the user may rest the hair dryer upon a work surface such as a counter top or shelf. This requirement of removing a diffuser prior to stowing the hair dryer is detrimental to use and often results in the hair dryer sliding off the work surface and impacting the floor. Such an impact with the floor or other hard surface is normally detrimental to the hairdryer.
As can be understood looking to one embodiment of the right hand hook 48 shown in FIG. 2 , to place the hair dryer in the hook 48 , the user may lift (rotate) the handle of the hair dryer to clear the arms 52 and 56 , reposition the hair dryer leftwards (laterally) into the receiving portion of the hook 48 . Normally the user would then lower (rotate) the handle 74 such that the exhaust port 62 would engage the inner portions of both arms 52 and 56 , thus holding the hair dryer in place without any significant repositioning of the arms ( 52 / 56 ) of the hook 48 relative to each other. If no large diffuser 64 or similar component is used, the exhaust portion 62 may be longitudinally inserted into the hook 48 in a traditional manner. In either case, no lateral force must be engaged against the system 20 to laterally position a hair dryer in place. These actions of placing a hair dryer in a right hand hook would be reversed to place a hair dryer in a left hand hook.
In another embodiment, the arms 52 and 56 may be slightly flexible, and deform away from each other slightly if the diameter of the hair dryer is larger than the net gap 58 .
Looking to the embodiment of FIGS. 5 and 6 , it is understood that the apparatus may utilize a plurality of substantially mirror image hooks 48 a and 48 b on alternate sides of the support 22 as previously mentioned. It can also be seen by comparing FIGS. 5 and 6 , how a hook 48 a will be repositioned from one side to the other when the apparatus is converted from a free-standing or horizontal application as shown in FIG. 5 , to a wall mounted operation as shown in FIG. 6 .
One significant advantage of the embodiments shown in FIGS. 1, 3, 5 and 7 is that the base 24 can be used as workspace to receive hairbrushes, combs and other elements while the overall apparatus does not significantly reduce the workspace available to an operator as the base 24 can be used as a substantially planar portion of the workspace. The embodiments shown in FIGS. 2, 4, 6, and 8 , also clearly do not reduce the workspace available to an operator as these embodiments are attached to a wall or other substantially vertical surface such as a cabinet etc.
As the tubes 34 and hooks 48 are positioned above the base 24 in a table top arrangement, the base 24 provides a very stable platform, especially when the overall apparatus is made of a relatively heavy material, such as heavy gauge aluminum, steel, or high-density polymers. The base 24 may also be thermally isolated, and held from sliding across the surface of the workspace by feet 66 which can be seen in FIGS. 1, 3, and 5 .
While the present invention is illustrated by description of several embodiments and while the illustrative embodiments are described in detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications within the scope of the appended claims will readily appear to those sufficed in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicants' general concept. | This disclosure relates to the field of holders for the storage of hair care appliances and similar articles wherein the hair-care appliances are stored (held) for immediate use. A thermal barrier clip for use with flat irons is also disclosed for use with the holder so as to improve safety and increase the lifespan of the flat iron. A hair dryer hook is also disclosed which allows for storage of a hair dryer with a diffuser attached. | 0 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a method and system for refilling brake circuits after rapid compressed air consumption.
[0002] Multi-circuit protective valves are known that divide an-energy supply into several mutually independent consumer circuits and, in the event of failure of a circuit, for example by line rupture, maintain a minimum pressure in the intact circuits. If a defect allowing more air to be lost than can be refilled by the compressor occurs in a service-brake circuit, the pressure in the service-brake circuits drops mutually until the closing pressure of the valve is reached. The pressure in the defective circuit continues to drop, whereas the closing pressure is maintained in the intact circuits. While the pressure in the defective circuit continues to drop, the circuits that are still intact can be refilled by the compressor until the opening pressure of the defective circuit is reached. A dynamic equilibrium is established in which the delivered compressed air can supply the circuits that are still intact (as well as secondary consumer circuits), although at the same time air is being lost via the defect. A disadvantage of such known multi-circuit protective valves is that refilling by the compressor takes a relatively long time because the compressor has only a relatively small delivery capacity, approximately 200 to 400 liters per minute. Accordingly, the nominal energy in the brake system is restored slowly—representing a disadvantage with respect to system safety.
SUMMARY OF THE INVENTION
[0003] Generally speaking, in accordance with the present invention, a method and system are provided whereby the air pressure in vehicle brake circuits can be restored rapidly after rapid compressed air consumption.
[0004] In accordance with the present invention, the brake circuits are filled, after rapid air consumption, from a high-pressure consumer circuit in addition to the compressor. Since a high-pressure circuit can usually deliver a much larger air flow per unit time (up to several thousand liter/min.) than a compressor (approximately 200 to 400 liter/min.), the intact brake circuits are refilled much faster than merely by means of the compressor. As a result, the nominal energy in the brake system, possibly reduced by a defective circuit, can be restored in a very short time. This is particularly important after a circuit break. System safety is substantially improved by distributing the energy between the circuits. This is achieved according to the present invention by providing, for the high-pressure circuit, an electrically actuatable valve that is closed in the de-energized normal state, preferably a solenoid valve (alternatively, a pilot-controlled valve can be used), and, for the other consumer circuits, including the brake circuits, electrically actuatable valves that are open in the normal state, preferably solenoid valves. All solenoid valves are in communication with one another via a common distributor line. To fill the brake system, the solenoid valve of the high-pressure circuit is switched to open position in order to allow compressed air to flow out of the high-pressure circuit in which the pressure or the energy has been conserved via the open solenoid valves into the intact brake circuits.
[0005] Still other objects and advantages of the present invention will in part be obvious and will in part be apparent from the specification.
[0006] The present invention accordingly comprises the various steps and the relation of one or more of such steps with respect to each of the others, and embodies features of construction, combinations of elements, and arrangements of parts which are adapted to effect such steps, all as exemplified in the construction herein set forth, and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The present invention will be described in more detail hereinafter on the basis of the accompanying drawings, in which:
[0008] FIG. 1 is a schematic diagram of a compressed air system according to an embodiment of the present invention; and
[0009] FIG. 2 is a graphical representation showing pressure variations during an operation of refilling of a brake system in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] Referring now to FIG. 1 , where compressed air lines are represented by solid lines and electrical lines by broken lines, there is shown a compressed air system 2 with a compressed air supply part 4 and a consumer part 6 . Compressed air supply part 4 includes a compressor 7 , a compressor control device 8 and an air-dryer part 10 .
[0011] Consumer part 6 is provided with a compressed air distributor line 14 , a plurality of electrically actuatable solenoid valves 16 , 18 , 20 , 22 , 24 with restoring springs and a plurality of compressed air consumer circuits 26 , 28 , 30 , 32 , 34 , 36 , 38 supplied with compressed air via the solenoid valves.
[0012] From compressor 7 , a compressed air supply line 40 leads via a filter 42 , an air dryer 44 and a check valve 46 to distributor line 14 , from which there are branched off lines 48 , 50 , 52 , 54 , 56 leading to the solenoid valves. From the solenoid valves, compressed air lines 58 , 60 , 62 , 64 , 66 lead to the consumer circuits. Line 62 splits into lines 62 ′ and 62 ″ leading to circuits 30 and 32 , a check valve 68 also being disposed in line 62 ″. A pressure limiter 70 is disposed in supply line 52 . Line 54 , which leads to solenoid valve 22 , branches off downstream from pressure limiter 70 . Line 64 splits into lines 64 ′ and 64 ″ leading to circuits 34 and 36 .
[0013] Pressure sensors 72 , 74 , 76 , 78 , 80 , 82 monitor the pressure in the compressed air consumer circuits and in distributor line 14 , and transmit the respective pressure as a pressure signal to electronic control unit 84 , which controls the solenoid valves.
[0014] As an alternative to pressure, it is also possible to monitor other variables of state, such as air flow rate, air mass and energy, in the consumer circuits and in the connecting line.
[0015] Compressed air consumer circuits 26 , 28 can be, for example, service-brake circuits. Compressed air consumer circuit 30 can be a trailer-brake circuit, in which case normally two lines, a supply line and a brake line, lead to the trailer. Compressed air consumer circuit 32 can be a parking-brake circuit with spring accumulator. Compressed air consumer circuits 34 and 36 can be secondary consumer circuits, such as operator's cab suspension, door controller, etc., in other words, all components that have nothing to do with the brake circuits. Compressed air consumer circuit 38 can be a high-pressure circuit.
[0016] Service-brake circuits 26 , 28 are provided with compressed air reservoirs 90 , 92 in conformity with EU Directive 98/12. High-pressure circuit 38 is provided with a compressed air reservoir 39 .
[0017] The inventive compressed air system makes it possible to dispense with compressed air reservoirs in circuits 30 , 32 , 34 , 36 . As an example, it is permissible to supply other compressed air consumer circuits from the service-brake circuits (circuits 26 and 28 ), provided the braking function or braking action of service-brake circuits 26 and 28 is not impaired.
[0018] Via a line 40 ′, compressor 7 is mechanically (pneumatically) controlled by compressor controller 8 . Compressor controller 8 includes a solenoid valve 94 of small nominal width that can be switched by electronic control unit 84 . In the de-energized normal state it is vented, as illustrated, whereby compressor 7 is turned on. If compressor 7 is to be turned off, for example because all compressed air consumer circuits are filled with compressed air, control unit 84 changes over solenoid valve 94 so that the pressure-actuatable compressor is turned off via line 40 ′. If solenoid valve 94 is switched to de-energized condition, for example because a compressed air consumer circuit needs compressed air, solenoid valve 94 is again switched to the normal state illustrated in the drawing, whereby line 40 ′ is vented and compressor 7 is turned on.
[0019] Air-dryer part 10 includes a solenoid valve 100 with small nominal width. An inlet 102 is in communication with distributor line 14 . A shutoff valve 106 , which is in communication with supply line 40 of compressor 7 and is used for venting of the air dryer, is pneumatically switched via an outlet 104 .
[0020] When solenoid valve 100 is switched to passing condition, compressor 7 no longer discharges into the consumer circuits but instead discharges to the atmosphere via valve 106 . At the same time, dry air flows from distributor line 14 (out of reservoirs 90 , 92 of the service-brake circuits) to the atmosphere via solenoid valve 100 , throttle 108 and a check valve 110 , through air dryer 44 for regeneration of its desiccant and further via filter 42 and valve 106 .
[0021] Reference numeral 112 denotes an overpressure valve.
[0022] Solenoid valves 16 , 18 , 20 , 22 , 24 are controlled by control unit 84 , solenoid valves 16 to 22 of compressed air consumer circuits 26 to 34 being open in de-energized normal state, while solenoid valve 24 of high-pressure circuit 38 is closed in de-energized normal state. Pilot-controlled solenoid valves can also be used. The pressure in the circuits is directly monitored at the solenoid valves by pressure sensors 72 , 74 , 76 , 78 , 80 .
[0023] If the pressure were to drop in a compressed air consumer circuit, for example in circuit 30 (trailer-brake circuit), the supply of compressed air also is effected by the service-brake circuits 26 and 28 via the open solenoid valves, the pressure in secondary compressed air consumer circuits 30 to 36 being adjusted by pressure limiter 70 to a lower level, such as, for example, 8.5 bar, than the pressure level of, for example, 10.5 bar in service-brake circuits 26 and 28 . High-pressure circuit 38 is normally shut off by solenoid valve 24 , and therefore is not in communication with the other circuits. The high-pressure circuit usually has a higher pressure than the other compressed air consumer circuits, such as, for example 12.5 bar.
[0024] In the inventive compressed air system, the pressure in compressed air consumer circuits 26 to 38 is measured by means of pressure sensors 72 to 80 , which transmit electrical pressure signals to electronic control device 84 for evaluation. The control device compares the measured pressure values with a lower threshold value, which corresponds to the pressure to be adjusted in the respective compressed air consumer circuit. If the pressure of the brake circuits drops below this threshold value due to rapid air consumption or to line rupture or break, the control device switches solenoid valve 24 of high-pressure circuit 38 to open position so that the high-pressure circuit is in communication with brake circuits 26 and 28 via connecting line 14 and open solenoid valves 16 and 18 and the energy stored in the high-pressure circuit is directed into the intact brake circuits and the intact brake circuits are refilled. At the same time, control device 84 shuts off the defective circuits by switching their solenoid valves to closed position; and compressor 7 also delivers into the intact brake circuits.
[0025] Refilling takes place very rapidly because the high-pressure circuit delivers a greater air flow per unit time into the brake circuits (up to several thousand liter/min.) than the compressor (approximately 200 to 400 liter/min.).
[0026] When the control device senses that the pressure in the high-pressure circuit and the pressure in the filled brake circuits are equal or that the index pressure value has been reached in the brake circuits, the control device closes solenoid valve 24 once again to interrupt the communication with the brake circuits.
[0027] It should be appreciated that the inventive method ensures distribution of energy between the consumer circuits, the salutary result being safe vehicle operating conditions.
[0028] Referring now to FIG. 2 , the pressure variations during a brake-circuit failure due, for example, to a line break in brake circuit 26 at instant 120 , and during refilling of intact brake circuit 28 at instant 124 , are shown. In addition to the pressure drop in circuit 26 (see curve 72 ), the pressure in brake circuit 28 (see curve 74 ), which is in pneumatic communication, and in connecting line 14 (not illustrated) also drops. The pressure drop in connecting line 14 results in solenoid valve 94 , which turns on the compressor, being actuated at instant 121 . To resupply intact brake circuit 28 with air, solenoid valve 24 of high-pressure circuit 38 is switched to the open state at instant 124 , and defective brake circuit 26 is closed approximately at the same time by the closing of solenoid valve 16 , so that intact circuit 28 , and if necessary pneumatically coupled circuits 30 and 36 , which are also intact, can be rapidly resupplied with air. The pressure in circuits 30 and 36 undergoes little change during the entire venting operation since pressure limiter 70 ensures decoupling of the pressure sensors from distribution line 14 (see broken pressure curves 76 , 78 ).
[0029] In FIG. 2 , the closing of solenoid valve 16 is illustrated at an instant 123 , which occurs shortly before instant 124 ; this is explained in greater detail hereinafter. With the opening of solenoid valve 24 of high-pressure circuit 38 and the closing of defective brake circuit 26 at instant 124 , the pressure in brake circuit 28 rises very rapidly, until the pressure of the high-pressure circuit and the pressure of the brake circuit become equal or until the index pressure of the brake circuit is reached. The pressure drop in the high-pressure circuit during this rapid resupply with air can be detected at pressure sensor 80 (see drop of pressure curve 80 of high-pressure circuit 38 at instant 124 ). After it has been resupplied with air, circuit 28 is shut off for a certain time by switching solenoid valve 18 to blocked state at instant 125 . During this time, the high-pressure circuit is refilled via the compressor, which has been switched on since the actuation of solenoid valve 94 at instant 121 . To complete this refilling operation (instant 126 ), the control signals for solenoid valves 94 and 24 are reset once again, which means that solenoid valve 94 is electrically energized and solenoid valve 24 is switched to the closed normal state once again. Thereafter, the control signal for brake circuit 28 is also reset (instant 127 ), which means that solenoid valve 18 is switched to open normal state once again.
[0030] Reference numerals 122 and 123 denote two brief test blocking pulses with a duration of 0.2 sec., for example, transmitted to the control input of solenoid valve 16 before instant 124 of definitive blocking of defective circuit 26 . Such test blocking pulses can be used for safe detection of the failure of a circuit (circuit 26 in this case). The test blocking pulse at instant 122 blocks solenoid valve 16 for the indicated time interval of 0.2 sec. As a consequence of this blockage, the pressure at pressure sensor 74 in unaffected brake circuit 28 rises momentarily; because pressure reservoir 92 can supply air to intact circuit 28 once again when venting is interrupted by defective circuit 26 . With respect to defective circuit 26 , a faster pressure drop takes place at pressure sensor 72 during the time of the test blocking pulse-since repressurization by the intact circuits is interrupted. Since the pressure drops more rapidly only in circuit 26 during the test blocking pulse, the suspicion that this circuit is defective is strengthened. In order to be certain whether this conclusion is correct, this test can be repeated by turning off valve 16 several times in pulsed manner. In the example illustrated in FIG. 2 , this is done a second and third time at instant 123 . The pressure again drops more rapidly in circuit 26 . It is now definitively established that circuit 26 is the defective circuit. Thereafter, beginning at instant 124 , circuit 26 is kept blocked.
[0031] It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and since certain changes may be made in the above constructions without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
[0032] It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween. | A method and system is provided for refilling vehicle operational brake circuits after large consumption of compressed air. The operational brake circuits are compressed air consumer circuits of a consumer part of a vehicle compressed air system. The operational brake circuits also includes at least one additional compressed air consumer circuit provided with a compressed air reservoir. The actual pressure values in the operational brake circuits and in the additional compressed air consumer circuits are continuously determined and compared against a lower threshold value. If the values are below the threshold value, the identified operational brake circuits are blocked as defective and communication is established between the additional compressed air consumer circuits and the intact operational brake circuits in order to refill the operational brake circuits from the compressed air reservoirs of the additional compressed air consumer circuits. | 1 |
BACKGROUND OF THE INVENTION
This invention relates generally to tubes used in heat exchangers for transferring heat between a fluid inside the tube and a fluid outside the tube. More particularly, the invention relates to a heat exchanger tube having an internal surface that is capable of enhancing the heat transfer performance of the tube. Such a tube is adapted to use in the heat exchangers of air conditioning, refrigeration (AC&R) or similar systems.
Designers of heat transfer tubes have long recognized that the heat transfer performance of a tube having surface enhancements is superior to a smooth walled tube. A wide variety of surface enhancements have been applied to both internal and external tube surfaces including ribs, fins, coatings and inserts, to name just a few. Common to nearly all enhancement designs is an attempt to increase the heat transfer surface area of the tube. Most designs also attempt to encourage turbulence in the fluid flowing through or over the tube in order to promote fluid mixing and break up the boundary layer at the surface of the tube.
A large percentage of AC&R, as well as engine cooling, heat exchangers are of the plate fin and tube type. In such heat exchangers, the tubes are externally enhanced by use of plate fins affixed to the exterior of the tubes. The heat exchanger tubes also frequently have internal heat transfer enhancements in the form of modifications to the interior surface of the tube.
As is implicit in their names, the fluid flowing through a condenser undergoes a phase change from gas to liquid and the fluid flowing through an evaporator changes phase from a liquid to a gas. Heat exchangers of both types are needed in vapor compression AC&R systems. In order to simplify acquisition and stocking as well as to reduce costs of manufacturing, it is desirable that the same type of tubing be used in all the heat exchangers of a system. But heat transfer tubing that is optimized for use in one application frequently does not perform as well when used in the other application. To obtain maximum performance in a given system under these circumstances, it would be necessary to use two types of tubing, one for each functional application. But there is at least one type of AC&R system where a given heat exchanger must perform both functions, i.e. a reversible vapor compression or heat pump type air conditioning system. It is not possible to optimize a given heat exchanger for a single function in such a system and the heat exchangers must be able to perform both functions well.
To simplify manufacturing and reduce costs as well as to obtain improved heat transfer performance, what is needed is an heat transfer tube that has a heat transfer enhancing interior surface that is able to perform well in both condensing and evaporating applications. The interior heat transfer surface must be readily adaptable to being easily and inexpensively manufactured.
In a significant proportion of the total length of the tubing in a typical plate fin and tube AC&R heat exchanger, the flow of refrigerant flow is mixed, i.e. the refrigerant exists in both liquid and vapor states. Because of the variation in density, the liquid refrigerant flows along the bottom of the tube and the vaporous refrigerant flows along the top. Heat transfer performance of the tube is improved if there is improved intermixing between the fluids in the two states, e.g. by promoting drainage of liquid from the upper region of the tube in a condensing application or encouraging liquid to flow up the tube inner wall by capillary action in an evaporating application.
SUMMARY OF THE INVENTION
The heat exchanger tube of the present invention has an internal surface that is configured to enhance the heat transfer performance of the tube. The internal enhancement is a ribbed internal surface with the ribs being substantially parallel to the longitudinal axis of the tube. The ribs have a pattern of parallel notches impressed into them at an angle oblique to the longitudinal axis of the tube. The surface increases the internal surface area of the tube and thus increases the heat transfer performance of the tube. In addition, the notched ribs promote flow conditions within the tube that also promote heat transfer. The configuration of the enhancement gives improved heat transfer performance both in a condensing and a evaporating application. In the region of a plate fin and tube heat exchanger constructed of tubing embodying the present invention where the flow of fluid is of mixed states and has a high vapor content, the configuration promotes turbulent flow at the internal surface of tube and thus serves to improve heat transfer performance. In the regions of the heat exchanger where there is a low vapor content, the configuration promotes both condensate drainage in a condensing environment and capillary movement of liquid up the tube walls in a evaporating environment.
The tube of the present invention is adaptable to manufacturing from a copper or copper alloy strip by roll embossing the enhancement pattern on one surface on the strip before roll forming and seam welding the strip into tubing. Such a manufacturing process is capable of rapidly and economically producing internally enhanced heat transfer tubing.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings form a part of the specification. Throughout the drawings, like reference numbers identify like elements.
FIG. 1 is a pictorial view of the heat exchanger tube of the present invention.
FIG. 2 is a sectioned elevation view of the heat exchanger tube of the present invention.
FIG. 3 is a pictorial view of a section of the wall of the heat exchanger tube of the present invention.
FIG. 4 is a plan view of a section of the wall of the heat exchanger tube of the present invention.
FIG. 5 is a section view of the wall of the heat exchanger tube of the present invention taken through line V--V in FIG. 4.
FIG. 6 is a section view of the wall of the heat exchanger tube of the present invention taken through line VI--VI in FIG. 4.
FIG. 7 is a schematic view of one method of manufacturing the heat exchanger tube of the present invention.
FIG. 8 is a graph showing the relative performance of the tube of the present invention compared to two prior art tubes when the tubes are used in an evaporating application.
FIG. 9 is a graph showing the relative performance of the tube of the present invention compared to two prior art tubes when the tubes are used in a condensing application.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows, in an overall isometric view, the heat exchanger tube of the present invention. Tube 50 has tube wall 51 upon which is formed internal surface enhancement 52.
FIG. 2 depicts heat exchanger tube 50 in a cross sectioned elevation view. Only a single rib 53 of surface enhancement 52 (FIG. 1) is shown in FIG. 2 for clarity, but in the tube of the present invention, a plurality of ribs 14, all parallel to each other, extend out from wall 51 of tube 50. Rib 53 is inclined at angle α from tube longitudinal axis a r . Tube 10 has internal diameter, as measured from the internal surface of the tube between ribs, D i .
FIG. 3 is an isometric view of a portion of wall 51 of heat exchanger tube 50 depicting details of surface enhancement 52. Extending outward from wall 51 are a plurality of ribs 53. At intervals along the ribs are a series of notches 54. As will be described below, notches 54 are formed in ribs 53 by a rolling process. The material displaced as the notches are formed is left as a projection 55 that projects outward from each side of a given rib 53 around each notch 54 in that rib. The projections have a salutary effect on the heat transfer performance of the tube, as they both increase the surface area of the tube exposed to the fluid flowing through the tube and also promote turbulence in the fluid flow near the tube inner surface.
FIG. 4 is a plan view of a portion of wall 51 of tube 50. The figure shows ribs 53 disposed on the wall at rib spacing S r . Notches 54 are impressed into the ribs at notch interval S n . The angle of incidence between the notches and the ribs is angle β.
FIG. 5 is a section view of wall 51 taken through line V--V in FIG. 4. The figure shows that ribs 53 have height H r and have rib spacing S r .
FIG. 6 is a section view of wall 51 taken through line VI--VI in FIG. 4. The figure shows that notches 54 have an angle between opposite notch faces 56 of γ and are impressed into ribs 54 to a depth of D n . The interval between adjacent notches is S n .
For optimum heat transfer consistent with minimum fluid flow resistance, a tube embodying the present invention and having a nominal outside diameter of 20 mm (3/4 inch) or less should have an internal enhancement with features as described above and having the following parameters:
a. the axis of the ribs should be substantially parallel to the longitudinal axis of the tube, or
α≈0°;
b. the ratio of the rib height to the inner diameter of the tube should be between 0.02 and 0.04, or
0.02≦H.sub.r /D.sub.i ≦0.04;
c. the angle of incidence between the rib axis and the notch axis should be between 20 and 90 degrees, or
20°≦β≦90°;
d. the ratio between the interval between notches in a rib and the tube inner diameter should be between 0.025 and 0.07, or
0.025≦S.sub.n /D.sub.i ≦0.07;
e. the notch depth should be between 40 and 100 percent of the rib height, or
0.4≦D.sub.n /H.sub.r ≦1.0; and
f. the angle between the opposite faces of a notch should be less than 90 degrees, or
γ≦90°.
Enhancement 52 may be formed on the interior of tube wall by any suitable process. In the manufacture of seam welded metal tubing using modern automated high speed processes, an effective method is to apply the enhancement pattern by roll embossing on one surface of a metal strip before the strip is roll formed into a circular cross section and seam welded into a tube. FIG. 7 illustrates how this may be done. Two roll embossing stations, respectively 10 and 20, are positioned in the production line for roll forming and seam welding metal strip 30 into tubing between the source of supply of unworked metal strip and the portion of the production line where the strip is roll formed into a tubular shape. Each embossing station has a patterned enhancement roller, respectively 11 and 21, and a backing roller, respectively 12 and 22. The backing and patterned rollers in each station are pressed together with sufficient force, by suitable means (not shown), to cause, for example, patterned surface 13 on roller 11 to be impressed into the surface of one side of strip 30, thus forming enhancement pattern 31 on the strip. Patterned surface 13 is the mirror image of the axially ribbed portion of the surface enhancement in the finished tube. Patterned surface 23 on roller 21 has a series of raised projections that press into the ribs formed by patterned surface 13 and form the notches in the ribs in the finished tube.
If the tube is manufactured by roll embossing, roll forming and seam welding, it is likely that there will be a region along the line of the weld in the finished tube that either lacks the enhancement configuration that is present around the remainder of the tube inner circumference, due to the nature of the manufacturing process, or has a different enhancement configuration. This region of different configuration will not adversely affect the thermal or fluid flow performance of the tube in any significant way.
The present tube offers performance advantages over prior art heat transfer tubes in both evaporating and condensing heat exchangers. Curve A in FIG. 8 shows the relative evaporating performance (H(GR)/H(SMOOTH)) of the present tube compared to a tube having a smooth inner surface over a range of mass flow velocities (G,LB/H-FT2) of refrigerant through the tube. By comparison, curve B shows the same relative performance information for a tube having longitudinal ribs but no notches and curve C shows the same information for a typical prior art tube having helical internal ribs. The graph of FIG. 8 shows that the evaporating performance of the present tube is superior to both prior art tubes over a wide range of flow rates.
In the same manner as in FIG. 8, curve A in FIG. 9 shows the relative condensing performance of the present tube compared to a tube having a smooth inner surface over a range of mass flow velocities of refrigerant through the tube. Curve B shows the same relative performance information for a longitudinally ribbed tube having no notches and curve C shows the same information for a typical helically ribbed tube. The graph of FIG. 9 shows that the condensing performance of the present tube is superior to both prior art tubes over a wide range of flow rates. | A heat exchanger tube having an internal surface that enhances the heat transfer performance of the tube. The internal surface has ribs that run substantially parallel to the longitudinal axis of the tube. The ribs have a pattern of parallel notches intersecting and impressed into them at an angle oblique to the longitudinal axis. The pattern of ribs and notches increase the total internal surface area of the tube and also promote conditions for the flow of refrigerant within the tube that increase heat transfer performance. | 5 |
FIELD OF THE INVENTION
This invention relates to a retaining wall block system and more particularly, to a plastic wall block comprising a frame adapted to receive a replaceable facing panel member which can also be used as a cap unit for the uppermost course of a plurality of courses of wall blocks forming a retaining wall. Removable spacing tabs are integrally formed with each wall block for adjusting the dimensional relationship of the top-to-bottom engaging means between blocks in superimposed courses to enable the user to selectively arrange the front faces of successive courses in either a vertically aligned or vertically set-back orientation. The side-to-side engaging means between juxtaposed blocks in a single course of blocks according to this invention is designed to permit the formation of retaining walls having straight, convex and/or concave facing portions without gaps therebetween.
BACKGROUND OF THE INVENTION
Retaining walls are commonly used for architectural and site development applications. Particularly for higher retaining walls, the wall facing must withstand significant pressure exerted by backfill soil or other aggregate. Reinforcement and stabilization of the backfill in such walls is commonly provided by grid-like sheet materials that are placed in layers in the fill material behind the wall face to interlock with the fill and create a stable reinforced mass. Connection of the reinforcing material to the elements forming the retaining wall holds the wall elements in place and resists backfill pressures.
One form of grid-like tie back sheet material used to reinforce the fill material behind such retaining wall structures may desirably be a uniaxially or biaxially oriented integral structural geogrid of the type which is commercially available from The Tensar Corporation of Morrow, Ga. ("Tensar") and is made by the process disclosed in U.S. Pat. No. 4,374,798 ("the '798 patent"), the subject matter of which is incorporated herein in its entirety by reference. However, other forms of grid-like tie-back sheet materials have also been used as reinforcing means in the construction of retaining walls, and the instant inventive concepts are equally applicable with the use of such materials.
In a brochure entitled "Concrete Geowall Package", published by Tensar in 1986, various retaining wall structures are shown using full height cast concrete panels. In one such retaining wall structure short strips, or tabs, of geogrid material are embedded in the cast wall panels. On site, longer strips of geogrid used to reinforce the wall fill and create a stable mass are connected to the tabs by passing a rod through loops formed by interleaving the strands of the geogrid sections, a connection sometimes referred to as a "Bodkin" joint.
Use of full height pre-cast concrete wall panels for wall facing elements in a retaining wall requires heavy equipment because the panels are very large and quite heavy, such that they cannot be readily manhandled. To avoid such problems, other types of retaining wall structures have been developed including walls formed from cementitious modular wall blocks which are typically relatively small by comparison and can be arranged in a plurality of single individual superimposed courses, much like laying of brick or the like, by a single individual.
Because of the high-speed method of forming cementitious wall blocks, it is not practical to embed tabs of geogrid or the like in the blocks for attachment to grid-like reinforcing sheets by a Bodkin-type connection as in the cast concrete panels. Therefore, other means for securing reinforcing grid to selected concrete modular blocks in the construction of a retaining wall were devised. Some techniques engage end portions of the reinforcing sheets between layers of wall blocks, relying primarily on the weight and engagement of large surfaces of the superimposed blocks to secure the grid; however, the very rough cementitious surfaces tends to abrade, and thereby weaken, the polymeric sheet material at the very point of interconnection. Other techniques rely on pins, staples or comb-like elements to capture the geogrid and minimize these problems. Preferred constructions are seen in U.S. Pat. Nos. 5,540,525, 5,595,460 and others assigned to Tensar, the subject matter of each of which is incorporated herein in its entirety by reference.
Although such cementitious wall blocks are individually lighter and easier to manufacture and use than full height, pre-cast concrete wall panels, they are still fairly expensive and relatively heavy, malding them cumbersome and inconvenient, particularly for use in constructing relatively low retaining walls such as are commonly found in home landscaping. Additionally, the nature of the materials used in the production of such prior art modular wall blocks limits the versatility in design and aesthetic presentation in the finished product.
A relatively simple and inexpensive wall block system usable by a consumer to readily erect a retaining wall is described in U.S. Pat. No. 5,568,999, assigned to Tensar, and hereby incorporated by reference in its entirety. In the '999 patent, the wall blocks are formed of plastic or other light-weight, easily molded materials and may be laid in a plurality of superimposed courses, with the blocks in each course laterally staggered relative to the blocks above and below. The individual wall blocks of the '999 patent include a plurality of fingers to capture end portions of extended lengths of geogrid or the like, if it is necessary to reinforce the fill material supporting the retaining wall.
The plastic wall block of the '999 patent may be molded of structural foam or the like as an integral product with a vertically extending member, the front of which may comprise any desired configuration to form a portion of the facing of the retaining wall. A generally horizontal bottom member or base extends rearwardly from the lowermost edge of the front member, and a somewhat shorter top member extends rearwardly from the uppermost edge. To integrate superimposed blocks top-to-bottom, the bottom member of each wall block in the '999 patent is provided with downwardly and forwardly extending hooks adapted to engage the top members of a pair of staggered underlying juxtaposed blocks in a lower course. The hooks are positioned and dimensioned to rearwardly shift blocks relatively to the course below, thereby vertically offsetting the front faces of superimposed courses in the resultant retaining wall. By changing the dimensional relationship of the elements, wall blocks can be provided which produce a retaining wall with the front faces of superimposed courses vertically aligned. However, the wall blocks of the '999 patent cannot be adapted by the user to enable the front faces of superimposed courses in the retaining wall to be selectively vertically aligned or offset using the same block. This necessitates the production of different blocks for specific applications, creating additional expense in manufacture and inventory.
As a related problem, no specific provision is made for a cap unit or cover for the uppermost course of blocks to provide the retaining wall with an aesthetically attractive appearance. Since the plastic wall block system of the '999 patent is particularly adapted for home landscaping, a finished look is obviously a desirable feature. With the '999 system, a separate and unique cap unit would be necessary, even further exacerbating the manufacturing and inventory costs.
Another limitation in the design of the plastic wall blocks of the '999 patent resides in the side-to-side engagement of blocks in the same course. Each block of the '999 patent includes a short sidewall extending rearwardly at right angles to the front face. On one side, the side wall is provided with a vertically extending, outwardly projecting lip defining a forwardly facing arcuate surface while the opposite side wall of each block includes a recess. The bottom edge of the lip of one block rests on the bottom edge of the recess of a juxtaposed block and the arcuate surface of the lip receives the vertical edge of the recess when adjacent wall blocks in a course of wall blocks are interengaged.
The top and bottom members of the blocks converge inwardly and rearwardly from the sides edges of the front face. The arcuate nature of the lip on the side of the wall block, in combination with the converging top and bottom members, facilitate the construction of a curved retaining wall from the blocks. However, to some extent, the top-to-bottom interconnecting means of the '999 patent interferes with the formation of an arcuate wall portion. Moreover, in order to form a retaining wall where the front facing defines a convex curve with the blocks of the '999 patent, because the sidewalls extend perpendicularly to the front wall, small gaps are formed between juxtaposed blocks in each course, further diminishing the structural integrity and aesthetic appearance of the resultant wall. The provision of a modular wall block with top-to-bottom and side-to-side engagement means that permit the formation of a course of straight, concave and/or convex portions without gaps between adjacent blocks would obviously be preferred.
Thus, it can be seen that the plastic wall block system of the '999 patent has many advantages over the use of cast concrete panels or cementitious modular wall blocks according to the prior art. However, several features of the patented system are less than perfect.
SUMMARY OF THE INVENTION
Accordingly, it is a primary object of the instant inventive concepts to provide a plastic wall block system which overcomes the aforementioned disadvantages of the '999 patented blocks, and incorporates highly versatile elements having multiple uses for different applications.
Consistent therewith, it is one object of this invention to provide a modular plastic retaining wall block with a facing panel which is removably attachable to portions of a wall block frame through a simple tongue-in-groove connection, enabling the facing panel to be readily replaced if damaged, or if a different pattern is desired on the face of a retaining wall to be formed from such blocks.
To even further enhance the versatility of the elements of the wall blocks of this invention, the facing panel is preferably designed to enable the same to be turned at 90° and received over the uppermost course of blocks in a retaining wall to form an aesthetically attractive cap unit therefor. When used in this fashion, the normally vertically extending facing portion will extend horizontally and at least partially cover the top blocks to provide the retaining wall with a finished appearance, without the need for a discrete or separately formed cap unit.
Thus, with this system, facing panels of infinite color and pattern variety may be readily attached to, and if desired, removed from, a wall block frame constructed in accordance with the principles of the present invention. Moreover, these same facing panels are adapted to function as cap units for the uppermost course of blocks in the retaining wall.
Another important object of this invention is the provision of a plastic wall block designed to selectively form retaining walls which may include straight, concavely curved or conversely curved sections, with the front facing portions of juxtaposed blocks in each course in direct contact with other, thereby providing a continuous retaining wall face regardless of the orientation of the blocks. To facilitate curving the wall, the top-to-bottom connection means of the wall blocks of this invention include abutting arcuate surfaces which provide point contact minimizing interference and enabling the wall blocks to be laterally staggered and more readily angled to form a concave or convex curvature to the retaining wall face.
Additionally, each of the sidewalls of the wall block of this invention follow the inward and rearward convergence of the bottom member of the wall block frame, rather than extending perpendicularly to the front face as in the '999 patent. One sidewall terminates at a free edge defining a flat surface, and the opposite side wall is provided with an outwardly projecting, arcuate lip terminating in a flange which extends from the curved surface back towards the front wall of the block frame.
In positioning adjacent blocks in a course of blocks, the free edge of a sidewall of one block engages the curved surface of the lip of an adjacent block. If desired, the front faces of the adjacent blocks can be aligned to form a straight portion of the retaining wall. However, by pivoting two adjacent blocks in a course of blocks with respect to each other, a concavely or convexly curved wall portion may be formed. By angling the blocks until the sidewalls contact each other, or one sidewall engages the flange on the arcuate lip of the adjacent block, curvatures ranging from, on the order of 22.5° to about 157.5°, for example, can be provided without the formation of gaps between juxtaposed blocks as in the '999 patent.
Yet a further object of this invention is to provide a simplified plastic wall block design which incorporates means to enable a user to readily modify the block for the selective construction of a retaining wall with vertically aligned or vertically stepped-back front face portions in superimposed courses. In this respect, each block, as molded, is designed to produce a retaining wall with a vertical face. However, removable spacing tabs are connected to the frame of each block by thin, frangible, bridging pieces. The depth of the grooves formed by the depending hooks which normally engage the top members of a pair of laterally staggered wall blocks in a lower course may be reduced when fitted with the spacing tabs, thereby selectively reducing the overlap between the courses, causing the upper wall blocks to be offset rearwardly, if desired.
Another object of the present invention to provide a plastic modular wall block of the type described including grid-engaging fingers extending upwardly from the bottom member for receiving and retaining sections of geogrid or other such tieback means if it is desired or necessary to reinforce the mass of fill material, such as soil, behind the retaining wall.
The above and other objects of the invention, as well as many of the attendant advantages thereof, will become more readily apparent when reference is made to the following detailed description, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a preferred form of a plastic wall block frame according to the instant inventive concepts with dotted lines illustrative of surfaces concealed from view:
FIG. 2 is a rear view of the wall block frame of FIG. 1;
FIG. 3 is a right side elevational view of the wall block frame of FIG. 1;
FIG. 4 is a rear view of a facing panel for use with the wall block frame of FIG. 1;
FIG. 5 is a plan view of the facing panel shown in FIG. 4;
FIG. 6 is a right side elevational view of the facing panel of FIG. 4;
FIG. 7 is an exploded schematic view of a wall block frame, a facing panel and a spacing tab according to the instant inventive concepts;
FIG. 8 illustrates an assembled view of the wall block frame and facing panel, with a spacing tab engaged with the frame to set-back the front faces of superimposed courses of wall blocks, and with end portions of an extended length of geogrid captured by grid engaging fingers on the wall block frame;
FIG. 9 is an exploded schematic view similar to FIG. 7 and including an additional facing panel repositioned for use as a cap unit;
FIG. 10 is an assembled view of the components of FIG. 9 with a length of geogrid affixed thereto;
FIG. 11 is a rear view illustrating the incorporation of a cap on the wall block frame;
FIG. 12 is a side view of a retaining wall formed by a plurality of courses of wall blocks of the present invention with the front faces of the wall blocks vertically aligned between successive courses;
FIG. 13 is a schematic perspective view of a retaining wall formed of a plurality of courses of wall blocks according to this invention;
FIG. 14 is a view similar to FIG. 12 with the spacing tabs positioned to vertically offset the front faces of successive courses of wall blocks;
FIG. 15 illustrates the side-to-side interconnection of two adjacent wall blocks in the formation of a course of blocks with their front facing surfaces in a straight alignment;
FIG. 16 is a view similar to FIG. 15 with adjacent blocks angled to form a slightly concaved front facing; and
FIG. 17 illustrates the formation of a slightly convex front facing by a pair of adjacent wall blocks according to this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In describing a preferred embodiment of the invention illustrated in the drawings, specific terminology will be used for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. Likewise, while preferred dimensions are set forth to describe the best mode currently known for the plastic wall block system of this invention, these dimensions are illustrative and not limiting on the instant inventive concepts.
For example, the illustrated dimensions are more appropriate for wall blocks to be used by the end consumer in the formation of retaining walls of limited scope. It is envisioned as being within the inventive concepts of the present invention to enlarge the scale of the depicted wall blocks for use in the construction of retaining walls of greater magnitude such as may be necessary for civil engineering structures.
With reference now to the drawings in general, and FIGS. 1 through 3 in particular, a preferred embodiment of a plastic wall block frame is schematically shown at 20 as comprising a front member 22, a bottom member 24 and short rearwardly extending, inwardly converging, sidewalls 26, 28 extending between the bottom member 24 and front member 22.
The side edges 30, 32 of the bottom member 24 taper inwardly from the front member 22 at an angle of approximately 80° for a distance slightly greater than the length of attachment of the sidewalls 26, 28, and then decreasing to an angle of taper of approximately 57.5° towards a rearmost edge 34 which extends substantially parallel to front member 22.
A plurality of reinforcement ribs may extend between the front member 22 and the bottom member 24. As illustrated, a central reinforcement rib 36 extends from the front member to rearmost edge 34 of bottom member and symmetrically spaced pairs of ribs 38, 40 extend the full height of the front member 22 partially towards the rear. A recess 42 extends rearwardly from the uppermost edge 44 of the front member 22 partially across the top of each of ribs 36, 38 and 40 to accommodate portions of a facing panel as described hereinbelow.
The bottom member 24 may be provided with a plurality of openings to minimize the plastic material, reduce the weight of the frame and facilitate the molding of undercut portions. In the illustrative embodiment, symmetrically spaced pairs of openings 46, 48, 50, 52, 54 and 56 are shown. Strengthening ribs, such as partially shown in dotted lines in FIG. 1 at 58, 60, may also be provided along the bottom surface 62 of the bottom member 24, if desired.
Projecting upwardly from the bottom member 24 are two pairs of grid-engaging fingers 68a, 68b and 70a, 70b. These fingers each include a vertically extending post section 68c, 70c, respectively, and a flat grid retaining portion 68d, 70d, respectively, extending parallel to the bottom member 24. The fingers 68a, 68b are located on one side of the central rib 36 and the fingers 70a, 70b are on the opposite side. In addition, fingers 68a and 70a are aligned laterally with respect to each other whereas fingers 68b and 70b are aligned laterally with respect to each other. The spacing of the fingers 68a and 68b as well as the spacing between fingers 78a and 70b are defined such that the fingers can fit within the openings of a grid-like sheet of reinforcing material. Accordingly, two adjacent wall blocks in a course of wall blocks will cooperate to capture end portions of an extended length of grid-like sheet of material between their respective reinforcement ribs 36. If wider sheets of reinforcing material are desired, they can be slit to preclude interference from the central ribs 36.
Side-to-side interconnection and alignment of laterally adjacent wall blocks in each course is effected by the engagement of the edge 78 of sidewall 26 with the curved surface of the arcuate lip 74 on sidewall 28 which terminates in a stop or flange 76. These elements enable juxtaposed blocks to be engaged with their front members substantially aligned as shown in FIG. 15 or angled to produce a convex curvature as shown in FIG. 16 or a concave curvature as shown in FIG. 17. With the sidewalls 26, 28 converging as illustrated, and the stop 76 on the arcuate lip 74 angled as shown, the blocks in a single course can be curved from approximately 22.5° to about 157.5° with the edge portions of adjacent blocks in direct contact with each to preclude the formation of gaps between blocks in each course. The extent of curvature in one direction is limited by engagement of the outside of sidewall 26 with the outside of sidewall 28; in the other direction the extent of curvature is limited by engagement of the inside of sidewall 26 with flange 76 on the arcuate lip 74 of sidewall 28.
A pair of tapered grooves or keyways 64, 66 are formed on the front member 22 of the wall block frame for interconnection of the frame 20 with a facing panel 80 illustrated in detail in FIGS. 4 through 8. The facing panel 80 can be molded in any color, and the front surface or face 82 can be provided with any selected pattern. When the facing panel 80 is mounted on the wall block frame 20 as described below, the facing member 84 overlies and conceals the front member 22 of the frame and the facing surface 82 defines a portion of the front face of the retaining wall formed from a plurality of wall blocks according to this invention.
A pair of T-shaped tongues 88 are defined on the rear surface 86 of each facing panel 80. Each tongue includes a base or stem 90 extending from the surface 86 and supporting an elongated cross-bar or top portion 92. As shown in FIGS. 4-6, the top portion 92 projects beyond three sides of the base portion 90 so as to define two side recesses 94 and an end recess 96.
A top member 98 of the facing panel 80 extends substantially perpendicularly to the facing member 84, and is provided with two pairs of reinforcing ribs 100, 102 on its undersurface to define recesses 104, 106 therebetween, respectively. The top member 98 also includes two arcuate surfaces 108 projecting from a trailing edge 110, and a centrally located slot 112 for purposes to be described below.
To attach a facing panel 80 to a wall block frame 20, the facing panel is initially positioned in the orientation shown in FIG. 7 with the facing member 84 extending vertically and the top member 98 positioned horizontally. The facing panel 80 is then moved downwardly into the position shown in FIG. 8 such that the tongues 88 fit into the slots 64, 66 in the front member 22 of the frame 20. The recesses 94 defined between the base 90 and top portion 92 of the tongues 88, engage the sidewalls of the slots 64, 66 to secure the facing panel 80 to the frame 20 with the facing member 84 covering the front member 22 of the frame 20. The top member 98 of the facing panel 80 is received in the recesses 42 on the top of the ribs 36, 38 and 40 with the uppermost portion of ribs 38, 40 received in the recesses 104, 106 to fix the facing panel 80 on the block frame 20 and reinforce the rigidity of this assembly.
To form a course of the retaining wall, laterally adjacent blocks are interconnected as shown, for example, in FIGS. 15-17. If the total height of the retaining wall to be formed by a plurality of courses is to be over six feet, it is recommended that the end portions of extended lengths of grid-like sheet material 114 be positioned between adjacent blocks.
As mentioned, preferred as reinforcing sheet materials are integral structural geogrids made by the process of the '798 patent. While a high density polyethylene biaxial integral structural geogrid of the type sold by Tensar as its BX 1200 geogrid, is most desirable, the grid may be formed of other polymerics, including other polyolefins, or various polyamides, polyesters or even steel (welded wire) or fiberglass. Additionally, structural grids made by other techniques, including woven or knitted grid-like sheets such as disclosed in co-pending U.S. patent application Ser. Nos. 08/643,182 and 08/696,604 filed May 9, 1996 and Aug. 14, 1996, respectively, assigned to Tensar, the subject matter of each of which is incorporated herein in its entirety by reference, may be readily adapted for use as the grid element according to this invention.
Utilizing the uniaxial techniques of the '798 patent, a multiplicity of molecularly-oriented elongated strands and transversely extending bars which are substantially unoriented or less-oriented than the strands are formed. The strands and bars together define a multiplicity of grid openings. With biaxial stretching, the bars are also formed into oriented strands. Regardless of the nature of the grid-like sheet of materials 114, the grid-connecting fingers 68a, 68b, 70a, 70b are spaced apart laterally equal to a multiple of the spacing between longitudinally extending strands 116 and are spaced apart longitudinally equal to a multiple of the spacing between the transversely extending strands 118. Not every grid opening need be engaged by one of the wall block fingers. Regardless of the spacing, transverse strands 118 in the end portions of the grid-like sheets 114 are engaged in the recesses 120 formed by the fingers 68a, 68b, 70a, 70b.
The strips of grid-like sheet material may be located between each course, i.e., between courses 124 and 126 and between courses 126 and 128, or only between selected courses or selected blocks 122a, 122b, 122c . . . , 124a, 124b, 124c . . . , and 126a, 126b, . . . , of a given course. See, for example, FIG. 13. The blocks are laterally joined as shown in FIG. 15. The length of the section 114 of grid-like sheet material may measure anywhere from, for example, 4 to 25 feet in length, and it is possible, at reduced heights, to eliminate the reinforcing material entirely, relying on the strike-through of the fill material through the openings in the bottom member 24 of each wall block frame 26 to hold a plurality of courses of wall blocks in place.
For vertically stacking successive courses of wall blocks according to this invention, downwardly and forwardly extending hook members 128 are provided on the bottom members 24 of each wall block frame 20. The hook members 128 each include a post 130 and a finger portion 132 which extends substantially parallel to the bottom member 24. A recess 134 is formed between the upper surface of the finger portion 132 and the bottom surface 62 of bottom member 24.
The leading edges 136 of the posts 130 are arcuate as seen in FIG. 1. Once the facing panels 80 have been secured to the wall block frames 20, the assembled wall blocks can be interconnected laterally to form a first course, and further courses can be built thereon. The top member 98 of a facing panel 80 is received in recesses 134 of hook members 128 on juxtaposed, staggered, blocks in a superimposed course with the arcuate leading surface edges 136 of the posts 130 engaging the arcuate surfaces 108 on the trailing edges 110 of the top members 98 of the blocks below. If adjacent blocks in a course of blocks are angled with respect to one another to form concave or convex portions of a retaining wall, the opposed arcuate surfaces, 136, 108, are in point contact, minimizing interference between the courses.
When the arcuate surfaces 136, 108 directly engage each other, the front faces 82 of facing panels 80 of successive courses of blocks are vertically aligned as shown in FIGS. 12 and 13. When it is desired to vertically offset or step back the faces of successive courses of blocks, spacing tabs 138 may be used. The spacing tabs 138, are formed integrally with the block frame 20, for example, in the openings 56 defined in the bottom member 24. The spacing tabs 138 are connected to the bottom member 24 by thin, frangible, bridging portions 140. By bending the spacing tabs 138 in and out of the plane of the bottom member 24, the bridging portions 140 will break to release the spacing tabs 138.
As shown in FIGS. 9, 10 and 14, by inserting the spacing tabs 138 into the recesses 134 formed by the hook members 128, the dimensional relationship between the hook members 128 and the top members 98 of superimposed wall blocks is adjusted to offset the front faces of successive courses by the depth of the spacing tabs. The arcuate surfaces 142 of the spacing tabs 138 are similar to the arcuate surfaces 136 of the posts 130 of the hook members 128 so as to engage the arcuate surfaces 136 on the top members 98, while wedging the spacing tab 138 in the recesses 134. Obviously, spacing tabs of different widths can be provided on each wall block frame (not shown) to allow the user to select the depth of the offset between the courses.
It is desirable to provide a cap unit which at least partially covers the blocks of the upper course in a retaining wall according to this invention without the need for a discrete element. Rotating a facing panel 80a by 90° as shown in FIG. 9, and moving the same downwardly and then forwardly until the arcuate surface 108 of a facing panel of a wall block in the upper course engages in the recess 96a formed between the base 90a and top portion 92a of the T-shaped tongue 88a enables a standard facing panel to be used as a cap unit as shown in FIG. 10. The cut-out or groove 112 in the top member straddles the rib 36 of the wall block frame 20 to stabilize the cap unit. See FIGS. 10, 12 and 14.
At a construction site, a plurality of plastic wall blocks are laterally interengaged to form an initial straight, angled or curved course. Selected grid-engaging fingers capture transverse strands or bars in the end portions of elongated lengths of grid-like sheet of material, the remainder of which is stretched out and interlocked with the fill soil or aggregate which is progressively back-filled as the courses are laid. The sheets of grid-like material may span a pair of wall blocks in a given course between their central ribs, at least in the production of a straight wall, and the grid-like material is embedded in earth which covers and interengages with the grid and the wall block frames to fix the course of blocks in position and creates a stable mass behind the retaining wall. Further courses of wall block are superimposed on the initial course, with the upper blocks laterally staggered with respect to the course below and interconnected by engagement of the hook members on the bottoms of the upper blocks with the top members of a pair of adjacent blocks below. Each course is covered with fill material in the same manner until the desired wall height has been reached. The final course may be provided with cap units in the manner described above.
The wall blocks of this invention may be of any size, for example, about 3 inches high and 12 inches wide at their front face, and 10 inches deep along their bottom members. For civil engineering purposes, more robust blocks may be provided. Similarly, the wall block may be formed of any suitable material. Desirable materials are polymers that may be structural foam molded, such as medium grade polypropylene. Such materials may be reinforced in a conventional way, i.e., by the addition of filler materials such as fiberglass of the like. A preferred block-forming material is a structural foam, that is, an injection molded engineering plastic, either preblended with a chemical blowing agent which, when heated, releases inert gas that disperses through the polymer melt, or into which an inert gas is introduced. When the gas/resin mixture is shot under pressure into the mold cavity, the gas expands within the plasticized material as it fills the mold, producing an internal cellular structure as well as a tough external skin at the mold face. Structural foams are well known and commercially available, for example, from General Electric as foamable grades of their LEXAN polycarbonate resins, NORYL thermoplastic resin and VALOX thermoplastic polyester resin. Further details of these resins and the structural foam process are found in The Handbook of Engineering Structural Foam published by General Electric, the subject matter of which is incorporated herein by reference. Alternative block-forming materials, foamed or otherwise, can be substituted therefor.
The foregoing description should be considered as illustrative only of the principles of the invention. Since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and, accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A modular plastic wall block to be used for forming a retaining wall including a plurality of vertically superimposed courses, each course including a plurality of laterally juxtaposed wall blocks. Each wall block is formed of a wall block frame and an easily replaceable facing panel interconnected by a tongue and groove connection. By rotating the facing panel by 90°, it can be used to overly and conceal at least a portion of the top of an uppermost course of wall blocks in the retaining wall. The wall blocks include elements for side-to-side connection enabling juxtaposed wall blocks in each course to be laterally aligned to form a straight portion of a face of a retaining wall, or to be angularly positioned to form concave or convex portions of the face of the retaining wall without the formation of gaps between adjacent wall blocks. Spacing tabs are removably carried by each wall block to enable the user to selectively adjust the spacing between the point of engagement between superimposed wall blocks and the front faces of the block below for the formation of vertical or stepped back retaining wall faces. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a generator and rechargeable battery system and more particularly to a generator and rechargeable battery system for use on a ski with an electrically operable load.
2. Discussion of the Background
The environment of the snow skier necessarily involves conditions of low temperature and is removed from the energy-derived comforts of the home. As a consequence, staying warm in such an environment is typically difficult and is at times nearly impossible. In particular, the skier's feet and toes are often exposed to extreme cold which can result in discomfort and even frostbite. Therefore, it can be seen that a ski equipped with a current generating mechanism could provide the skier with some of the heretofore missed comforts of home.
The prior art discloses heated boots and shoes which use a battery to power the heating elements involved. Examples of such devices are Santroch, U.S. Pat. No. 3,977,093, Balbinot, U.S. Pat. No. 4,697,359, Vaccari, U.S. Pat. No. 4,507,877, and Giese, U.S. Pat. No. 3,859,496. Difficulties arise with battery powered boots in that the heating elements use much power and the batteries are soon drained of electrical energy. As the batteries of the heating boots become drained of energy through use, the individual user is left unprotected from the cold. Therefore, a need for a recharging power source is apparent. With a recharging power source a skier would be able to remain comfortable in a frigid environment for an indefinite and extended amount of time.
Sartor, European Patent Office Publication No. 0207302A2, has proposed a ski manufactured with numerous solar cells which can generate electric current for use on an electrical load and which can store the current by means of a battery. However, Sartor's invention has a number of disadvantages. Since the solar cells are implanted into the surface of the ski at the time of manufacture, the invention is not adaptable to the conventional ski already in use. Furthermore, the solar cells cannot operate in the dark or in conditions of low light. Therefore, the use of the invention is optimized on clear, sunny days. Yet it is often on cold and overcast days that a skier is most in need of an energy source. Still another drawback of the solar cell ski is cost. The expensive nature of such a device would preclude it being used by a large number of skiers.
Solar celled ski boots have recently been introduced, Sartor, U.S. Pat. No. 4,697,360; however, little power can be generated through the solar cell and while negating the need for batteries, the expensive devices become worthless in low light conditions.
Small portable battery generator systems have a long history in pedal powered vehicles such as bicycles. The power provided by the legs of the bike rider is converted by the generator to electrical energy which typically is used to power a light mounted onto the bike's frame. Generator and rechargeable battery systems with their concomitant electronic circuitry are disclosed in Baker, U.S. Pat. No. 3,792,307, and Ryan, U.S. Pat. No. 4,555,656.
However, to date, no battery generator system has been devised that would utilize the kinetic an potential energy of a skier for purposes of generating an electrical current. The present invention utilizes the kinetic and potential energies of a skier by converting this energy by means of a rotating member which turns a drive shaft attached to a generator which is easily affixed to the ski. The electrical energy created can be used to power the heating elements in an electrically heated ski boot, to illuminate lighting fixtures attached to the ski, to power electrical appliances such as radios and tape players, and to recharge batteries which alternatively can be used to power the aforementioned electrical devices.
SUMMARY OF THE INVENTION
Accordingly, one object of this invention is to provide a novel generator and rechargeable battery system for use on a snow ski for the purpose of providing an electric current to the heating element of a ski boot.
Another object of the present invention is to provide a system for powering a light mounted onto a snow ski.
Yet another object of this invention is to provide a generator and rechargeable battery system which can be used to power the loads of any number of electrical devices such as a radio or tape player.
Still another object of the present invention is to provide a generator and rechargeable battery system which is light and compact and easily affixed to a conventional snow ski.
Briefly, these and other objects of the present invention are achieved by converting the kinetic and potential energy of the skier to an electric current. This is accomplished by means of a power roller which rotates as the ski moves along the ground thereby turning an axle which produces an electrical current by means of a generator which can be directed to charge the battery or power an electrical load.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
FIG. 1 is a perspective illustration of the generator structure of the present invention affixed to a snow ski showing the electrical interface with a heated boot;
FIG. 2 is perspective illustration of a snow ski showing a structure for removably mounting the generator of the present invention;
FIG. 3 is a perspective illustration of the generator housing illustrating particular details of the drive shaft;
FIG. 4 is a perspective illustration of a power roller suitable for use on hard packed or icy surfaces;
FIG. 5 is a perspective illustration of a power roller suitable for use in soft snow;
FIG. 6 is an illustration of an electrically heated boot illustrating an interface with the present invention;
FIG. 7 is an illustration of the bridging cable of the invention;
FIG. 8 is a further illustration of a modified bridging cable;
FIG. 9 is an illustration of the invention in use;
FIG. 10 is an illustration of adhesive stick wiring;
FIG. 11 is a schematic diagram of the electrical circuit of the invention; and
FIG. 12 is an illustration of an alternative electrical connector.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, and more particularly to FIG. 1 thereof, a generator housing 10 is shown coupled to a conventional ski 12 by means of a mounting bracket 14.
The generator housing 10 contains a small, lightweight, high output generator of the type disclosed in McDermott U.S. Pat. No. 2,299,762, for example, or any suitable conventional equivalent generator. This generator is securely mounted within the housing and is sealed by means of watertight seals to prevent moisture from entering it. A removable power roller 20 is coupled to the drive shaft 16 for engaging the surface beneath the ski 12 and converting the linear motion of the ski to a rotary motion for ultimate conversion to electric power by the generator 17. As can be seen, drive shaft 16 rotates gear train 19 which turns generator mechanism 18 resulting in the generation of electricity by the generator 17.
The electrical output of the generator is supplied to an output cord 22 which is preferably permanently connected to the generator housing 10 at its input end. The output cord 22 includes a y-joint 24 where a short branch 26 and a long branch 28 are joined. The short branch 26 culminates in a conventional watertight connector 30, illustrated as a female connector, which is adapted to be connected in a secure manner to a two prong male connector 32 formed integrally with electrically heated ski boot 34.
The long branch 28 of the output cord 22 culminates in a similar watertight connector 36 which is adapted to interconnect with bridge cord 38, to be described in more detail subsequently.
It is noted that the electrically heated boot is mechanically coupled to the ski 12 by means of conventional toe and heel bindings 40 and 42, respectively.
Reference is now directed to FIG. 2 which illustrates the manner in which the generator housing 10 is secured to the ski 12. Specifically, the mounting bracket 14 is first connected to the ski 12 by conventional means such as screws 44. The mounting bracket includes an interior groove 46 which is shaped to receive a flange 48 formed around the base of the generator housing 10. The mounting bracket 14 is preferably formed of a resilient, flexible plastic material which does not lose its resiliency at low temperatures. Similarly, the flange 48 may also be formed of a tough, resilient plastic material. The same material may be used to form the entire generator housing 10. In operation, the generator is inserted into the mounting bracket so that the flange 48 interfits in the interior groove 46. The flange and groove structure are conventionally shaped so as to form a strong friction fit. By this friction fit mechanism, the generator housing may be easily placed on the ski or removed from the ski when not in use to prevent theft or damage.
It is noted that the same type of housing and mounting assembly may be used to secure a rechargeable battery to the ski that is not carrying the generator. Alternatively, one or two rechargeable batteries may be mounted to a skier's boots as disclosed in U.S. Pat. No. 3,859,496. The battery 120 may also be contained within the generator housing 10, as illustrated in FIG. 1. If the storage battery is mounted on the opposite ski from the generator, the battery and generator are coupled together via the bridge cord 38 described in more detail subsequently.
Referring now to FIG. 3, the generator housing 10 is shown as including an on-off switch 50 which is used to switch on or off the electrical output of the generator 17. It is convenient to have an appropriate switch so that power delivered to the electrically heated boot 34 may be switched off on warm days or at other times when the user's feet do not need to be heated. As a alternative to the mechanically actuated on-off switch 50, a temperature responsive switching system can be incorporated into the generator housing. In this case, a temperature sensor 52 (illustrated in FIG. 6) is incorporated into the boot 34 to sense the temperature of boot heating element 54. When the temperature sensor 52 detects a predetermined temperature level, an appropriate output signal is applied over output line 56 and delivered to a conventional electrically responsive switch 57 (FIG. 11) which may replace the mechanical on-off switch 50, or be coupled in series with it.
Also illustrated in FIG. 3 is the drive shaft 16. This drive shaft is manufactured of a tough, resilient plastic material (e.g. a matrix/oriented fiber composite such as graphite/epoxy, carbon/epoxy, carbon/polyester, carbon/epoxy or fiberglass vinyl ester) so that it may flex to an extent when subjected to pressures, as would be the case when the skier is turning on the edge of the ski nearest the drive shaft 16. The drive shaft 16 includes a bushing 58 for positioning a power roller on the drive shaft and also includes a friction fastening structure 60 which is of conventional structure and is intended to permit a power roller to be installed or removed with convenience. The friction fit must, however, be strong enough to prevent the power roller from becoming disengaged during severe operating conditions. The portion of the drive shaft 16 carrying the friction fastener element includes splines 62 which interfit with appropriately shaped ribs 64 at the hub of suitable power rollers so that the rollers are firmly engaged in a nonslip fashion to the drive shaft 16. It is noted that while the shaft 16 is illustrated as extending outwardly from only one side of the generator housing 10, the shaft 16 may alternatively pass through the housing 10 and have a power roller attached at both ends.
Referring now to FIG. 4, a power roller 66 is shown which is adapted to be mechanically inserted on the friction fastener 60 for driving the generator 17. The power roller 66 is formed of a resilient plastic or rubber material that is deformable yet resilient so that it retains its round, cylindrical shape.
An open cell foamed polymer exemplifies the quality of material desired for the power roller. Examples include: cellular rubber open or closed cell, styrenebutadiene rubber with blowing agent; flexible cellular polymers, polyesterene (closed cell), polyethylene closed cell; flexible polyurethane. On the surface of the power roller 66 are embedded small spikes 68 made of metal or a hard plastic material that are adapted to engage hard packed snow or icy surfaces, and to prevent the power roller from sliding on such surfaces without rotating.
FIG. 5 illustrates another power roller 70 which is suitable for use in soft or unpacked snow. This power roller includes a series of semi-wedged shaped snow engaging feet 72 separated by spacer grooves 74. The design depicted enhances compressive capability while augmenting traction with the snow surface.
It is anticipated that the skier will review the skiing conditions most prevalent on the slopes when he reaches them. He will then select the power roller which will be most appropriate for those conditions. Clearly, other types of power rollers may also be adapted for use with the system for operation under conditions which are not suited to the two specific structures illustrated in FIGS. 4 and 5.
Referring now to FIG. 6, a wiring structure is illustrated which is an alternative to that illustrated in FIG. 1. Specifically, the output cord 22 is shown having only a single female plug 76 coupled to a male plug 78 mounted onto a rear portion of the boot 34. A permanent interior electrical connection 80 is secured within the boot 34 to couple the plug 78 to heating element 54. Another electrical wire or cable 82 is mounted within the boot 34 to interconnect plug 78 with an upper male plug 84. The bridge cord 38 is connected to this upper plug. This alternative wiring structure requires further modification of the boot 34 to include more internal wiring. However, the resultant pattern of electrical wiring is somewhat simplified relative to that shown in FIG. 1. However, the FIG. 1 structure does not require such an extensive modification of the boot 34 and requires only one conventional input plug 32 in the boot 34.
Reference is now directed to FIG. 7 which illustrates the bridge cord 38 in more detail. The bridge cord includes at its ends two female plugs 86 and 88. At suitable intervals along the bridge cord are mounted Velcro type or other equivalent fasteners 90 to permit the bridge cord to be coupled to the skier's clothing, as illustrated in FIG. 9. The bridge cord is necessitated by the fact that for economic reasons it will normally be desirable to have a generator mounted to only one ski. However, electric power must be supplied to both ski boots. This is accomplished by delivering electrical power from the generator mounted on the right ski 92 (FIG. 9) to the boot mounted to the left ski 94. The Velcro fasteners are suitable for quickly coupling the bridge cord to the skier's clothing.
The bridge cord may be mounted inside the skier's pants, as illustrated in FIGS. 1 and 9 or it may be mounted externally as illustrated in FIG. 6. Internal or external mounting is simply a matter of convenience and choice for the skier.
The bridge cord may also include an electrical outlet 96 so that the skier may connect other appliances such as a radio, tape player etc. to his generator 17. Similarly, the bridge cord may include a y-joint 98 as illustrated in FIG. 8 with a conventional electrical power plug or other output device 100 secured thereto.
Referring again to FIG. 2, other electrical appliances may be connected to the ski's, as desired. FIG. 2 illustrates a front running light 102 and a rear running light 104 secured to the ski 12 and connected to the generator 17 by means of adhesive strip wiring 106 and 108 respectively. The adhesive strip wiring, illustrated in FIG. 10 is preferably formed of a flat, two conductor cable 110 having a ready-stick adhesive 112 placed on a lower surface thereof. A removable paper or plastic strip 114 is placed over the adhesive so that the cable may be sold or stored without concern over the adhesive. When the cable 110 is to be applied to a ski 12, the removable paper 114 is stripped away exposing the adhesive surface and permitting the cable to be directly attached to the surface of the ski.
When this wiring technique is used, it is preferable to include electrical contacts 116 on the flange portion 48 of the generator housing 10. These electrical contacts mate with other suitably formed electrical contacts positioned within the interior groove 46 of the mounting bracket 14 so that when the generator housing 10 is inserted into the groove, the contacts mate. The contacts 116 are electrically connected internally from the generator housing 10 to the generator 17 so that power is supplied through these contacts to the adhesive flat cable to power running lights 102 and 104. It will be apparent to those skilled in the art that the running lights 102 and 104 may be replaced with other conventional electrical appliances.
Reference is now made to FIG. 11 which illustrates the electrical circuit of the present invention. The circuit is depicted as including generator 17 connected to a conventional full wave rectifier. A capacitor 122 is connected across the generator output for the purpose of minimizing any rippling effects in the rectification process. A diode 124 is interposed between the generator and storage battery 120 to insure that electrical current from the storage battery is not introduced to the generator. As can be seen, the storage battery is an additional power source which can supply the respective electrical loads with current and which can be supplied recharging current from the generator. The on-off switch 50 allows current to be supplied to the respective electrical loads during the on mode and prevents current from being circulated in the off mode. As can be seen from FIG. 11, the generator and rechargeable battery may be connected to the boot heating element 54 of each ski boot or to an electrical appliance 126.
In operation, a skier 118 first couples the bridge cord 38 to his ski pants, either externally or internally by using the fasteners 90. He then may mount the generator to one of his skis by inserting the flange 48 into the groove 46 within mounting bracket 14. The skier then makes the appropriate electrical connections to couple his heated boots 34 to the generator structure using output cord 22 to connect his right boot to the generator and coupling the output cord 22 to the bridge cord 38 to supply power to his left boot. The bridge cord provides complete freedom so that the skier may operate his skis in total disregard of the electrical connection attached to his pants.
In skiing, the power roller 66 or 70 engages the snow surface and rotates generator 17. In some instances, depending upon the way in which the skier is turning, the power roller may disengage itself from the snow. However, in this case, power is delivered to the boots or other electrical appliances by means of a conventional storage battery 120 housed either within the generator housing 10, or elsewhere, for example attached to the ski boots as shown in U.S. Pat. Nos. 3,859,496, 4,697,359 or 4,507,877. When the power roller engages the snow, the generator operates either by directly powering the electrically heated boots or by recharging the storage battery.
For the safety of the skier, it is noted that the various female and male connecting elements of the output cord and electrically heated ski boot interface in a water tight manner; however, the connection is easily separated by a light force so as to permit quick disconnection of the connecting elements should the skier's boots be released by the ski bindings, as often happens during falls on the ski slope.
An alternative electrical connector which facilitates disconnection is illustrated in FIG. 12 which depicts an electrically heated ski boot having two wedge-shaped metal electrical contacts 132 protruding from the ski boot's heel. These wedge-shaped metal electrical contacts fit into the wedge-slots 134 of a connector station 136. A weather seal 137 seals out water and ice from contacts 132. The connector station 136 which houses wedge-slots 134 is attached to the top of heel binding 42. This connector station is provided with a male connector element 32 which interfaces with the female connecting element 30 of output cord 22. The connector station thereby receives electrical current which is channeled through the wedge shaped electrical contacts and onto the heating element in the ski boot. In this manner electrical energy is supplied to the ski boot while providing the skier with an effective disconnection means should his ski boots become detached from the ski bindings. This wedge connector structure described here is preferably combined with the internally wired boot structure illustrated in FIG. 6.
All patents mentioned in the Description of the Preferred Embodiment are to be considered as incorporated by reference into the present disclosure. Although the invention is specifically described in conjunction with snow skis, it is understood that it is suitable for use with any type of ski including water skis and grass skis. Furthermore the invention can be used with slalom boards and skate boards and other similar types of devices.
Obviously, numerous additional 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 herein. | A generator and rechargeable battery system is disclosed for attachment to a ski having an electrically operable load. The invention comprises a rechargeable battery system in which the generator and/or battery can intermittently power a load such as a heating element of a ski boot. The rechargeable battery is detachable and may be recharged by the generator or in the home. Through the use of connecting wires, the generator and rechargeable battery system can be used to supply current to lights affixed to the ski and to power other electrical appliances. | 0 |
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates generally to a method and apparatus to keep track of the service life expectancy of wellbore intervention tools, and more particularly to an autonomous apparatus that is intended to follow the use and exposure of a wellbore intervention tool while continuously calculating a prediction of the remaining life expectancy of the tool monitored.
The tool service life is a percentage number and is based on a generic set of algorithms characterizing the influential failure-mechanisms verses exposure, workload, and time. The Tool Service Life Sensor (“TSLS”) is provided with wireless connectivity and may be interrogated in the well or at the surface. Upon interrogation, the TSLS will prompt the mission, the life expectancy left, tool identity and status, as well as particular events (above certain expectation limits). The TSLS may be integrated and be incorporated as part of a downhole intervention tool or it may have its own housing.
For those skilled in the art, this is not the downhole-tool version and substitution for an airplane “flight recorder” or “black box,” but a mission recorder telling the operator the status of the tool and how much future or “usable” life expectancy the tool provides. This is calculated and expressed directly by the TSLS in percentage design life left, and is based on historic (recorded) use. Further, it is an estimate of how many hours of use the life expectancy prediction represents. Secondarily, but just as importantly, the TSLS provides as output information the occurrence of damage-events as recorded outside a defined level.
U.S. Patent Application Publication No. 2006/0238161 A1, to Rusnell et al., describes a system that records the use versus load with time. This invention is intended for attachment to rental equipment in order to manage their charges and service. The latter is related to the use and workload recorded. This invention does not have the mission, or the ability, to predict the remaining “life” of a tool. Further, it does not include wireless connectivity, which in many applications is required as the tool and the TSLS target may be located in a remote location, non-accessible with a cable connection.
U.S. Patent Application Publication No. 2006/0085134 A1, to Dion et al., is a downhole memory recorder to be used in a well to record the usage of a tool. Operating data collected as well as peak conditions from the recorder are downloaded and used to evaluate the life and status of the mission tool in a surface database. This unit is not autonomous and does not on its own calculate the remaining life of a mission tool.
SUMMARY OF THE INVENTION
By the present invention all decisions and calculations of expected lifetime and occurrence are performed by sets of static algorithms describing the governing failure mechanisms considering the life of the unit verses time, load, use, and/or exposure, of which magnitude and impact are measured by an application-specific parametric sensor array of the TSLS. Consequently, lifetime prediction of this invention is static as described, and not a process based on human resources evaluating data records like those described in previous art.
According to the present invention, there is provided apparatus for calculating service life expectancy of wellbore intervention tools, the apparatus comprising one or more sensors, power means, control means, and wireless connectivity means. The application also provides a method for measuring the service life expectancy of wellbore intervention tools, in which apparatus according to the present invention is positioned in a wellbore adjacent to or near a tool to be monitored, measuring one or more physical properties with the one or more sensors in the apparatus, recording and processing the data obtained from the sensors, and calculating the expected life of the tool being monitored using the data collected. Preferred and optional features of the apparatus and method of the present invention will be clear from the accompanying claims and from the detailed description of an embodiment which follows.
All wellbore equipment has a certain life expectancy that is generally based on technology, material properties, ruggedness, and compatibility, to mention a few non-limiting parameters. Any use of a tool in a well will induce wear on the parts of which it consists. The wear may be categorized and broken down into segments of, for example, wear and tear, all of which may be calculated based on environment, material properties, function, and exposure. Further, in any tool there will be functions or components that are likely to wear out and fail before others due to the nature of the tool and its parts, as well as the technology utilized. Consequently, such a parameter or parameters will be the life-limiting factors of the tool and the governing factors for the service and work-over to proceed.
For the purpose of the invention, the governing life-limiting parameters are referred to herein as the “apparent failure mechanisms of the tool.” Further, and for the continuation of this process, the governing failure mechanisms of a mission intervention tool will be the criteria to calculate and predict its lifetime expectancy. Consequently, in general, all failure mechanisms may be characterized and their influence on the tool total life expectancy may be predicted based on use, workload, and time. Further, the use may be categorized as heavy or light and be dependent on which parameter and load that a user selects to distinguish between the two. Again, the outcome is a predictable reduction of a mission or tool service-life.
This apparatus is by definition a generic type “Tool Service Life Sensor” and will prompt the user with the status of the tool and how much more use it will take before it is to be taken out of service for overhaul or replacement. The life expectancy is calculated based on how many of the required number of algorithms that characterize the governing failure mechanisms upon which the tool-life is based and what physical property parameters or work-load are associated with them. The calculation of the tool life is in turn linked to integral sensor of the apparatus that is sequentially recorded to memory on each event and by time.
DESCRIPTION OF THE DRAWINGS
Referring now to the drawings, wherein like elements are numbered alike in the several FIGS.:
FIG. 1 shows an outline schematic of the Tool Service Life Sensor (“TSLS”) with its major components; and
FIG. 2 is a diagrammatic block diagram illustrating the electrical and functional configuration of the TSLS.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A first embodiment of the Tool Service Life Sensor (“TSLS”) and associated equipment are shown in FIG. 1 and FIG. 2 . Referring to FIG. 1 , a typical embodiment of the TSLS is illustrated. A housing 1 holds a main frame 3 containing components for the TSLS. The main frame 3 hosts a battery 30 , a sensor package 10 , a controller/recorder board 2 , an electromagnetic antenna 22 , and a wired connectivity element 9 . For practical means, the housing 1 provides an electrical feedthrough 8 for the operation of and connection to tools operated electrically. Finally, the housing 3 is provided with a threaded seal connection 7 for attaching to a mission tool (not shown).
The TSLS 3 communicate wirelessly to a remote link 5 which is controlled by a controller/computer device 4 . The controller/computer device 4 may be a traditional PC computer running a software application to interrogate the TSLS. Wireless connectivity between the units is indicated by the reference numeral 6 . The wireless connectivity 6 is through electromagnetic means and is functional in air at the surface and in fluids or gas which may be present in the wellbore.
Referring to FIG. 2 , a functional block diagram of the TSLS is shown. The first building block is the sensor package 10 . The sensor package 10 may consist of one or more sensors 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , etc. The sensors may measure properties selected from the following non-limiting list: temperature, temperature difference, pressure, differential pressure, vibration, chock, electric field, magnetic field, acceleration, load, displacement means, acoustic type, resistivity, relative humidity, thermal conductivity, pH, electrical potential AC/DC, electrical current AC/DC, tension, compression, torque, shear force, inclination, magnetic orientation, toolface, gravity, flow, turbidity, density, displacement, dimension, radiation, speed, frequency, weight, buoyancy, ratiometric type, electrical event type, as well as ambient conditions inside the housing 1 . The sensor package 10 may consist of one or more sensors, or a combination of one or more of all sensors listed.
Input signals from the sensor package 10 is multiplexed by a multiplexer 20 and is amplified/linearized accordingly by an amplifier section 21 . In turn, the output of the amplifier section 21 is fed to a controller 24 for acquisition. Due to the wide temperature operating range of the TSLS, the data acquisition is provided with a stable reference 32 for signal processing and comparison.
The TSLS is powered by the battery 30 and provides a stable output to a power supply 29 . The power supply 29 has a power supply output 31 which is the main electric source for the circuits and sensors of the TSLS. To keep track of time the controller 24 is connected to a timer or clock device 23 which is a stable time source to keep track of time even at elevated conditions. For those skilled in electronic arts, the times or clock device 23 of the TSLS may be a doubly rotated SC (SC=Sensitivity Cut) quartz crystal resonator. The TSLS is autonomous, and executes a program application set up and managed by the controller 24 . The program application is user defined, and is based upon analysis of the failure mechanisms of the mission element tool. Data processed and events recorded are stored in memory sections 26 , 27 , and 28 . The memory technology used may be any volatile or non-volatile type.
Connectivity is provided by a modem 25 and the electromagnetic antenna 22 . The TSLS also provides the wired connectivity 9 which may be used for hardwired communication where practical.
Although the foregoing description of the present invention has been shown and described with reference to particular embodiments and applications thereof, it has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the particular embodiments and applications disclosed. It will be apparent to those having ordinary skill in the art that a number of changes, modifications, variations, or alterations to the invention as described herein may be made, none of which depart from the spirit or scope of the present invention. The particular embodiments and applications were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby 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 changes, modifications, variations, and alterations should therefore be seen as being within the scope of the present invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled. | Apparatus for calculating service life expectancy of wellbore intervention tools comprising one or more sensors, power means, control means and wireless connectivity means. Also a method of the measuring and calculating the service life expectancy of wellbore intervention tools using this apparatus. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] Provisional patent application 60/645,679 filed Jan. 21, 2005
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] N/A
BACKGROUND OF THE INVENTION
[0003] This invention relates to aerosol dispensing containers incorporating a bag holding a product to be dispensed and a propellant chamber formed between the bag and container sidewall, and more particularly, to an improved grommet or fill valve (sometimes also referred to as an umbrella valve or seal valve) by which a propellant is introduced into the container and retained therein until all the product in the container is dispensed. Alternately, the container may employ a piston on one side of which is the product to be dispensed and on the other side of which is the propellant chamber. Again, the improved fill valve allows a propellant to be introduced into the chamber and retained therein until all the product is dispensed.
[0004] Certain types of aerosol containers include a collapsible bag or pouch disposed within the container. The bag or pouch is filled with a fluent material dispensed by the container. A propellant chamber is formed between the bag and container sidewall. At the base of the container, on a domed bottom surface thereof, an opening is formed and a fill valve is seated in this opening. During manufacture, after the bag or pouch is seated in the container and a dispensing valve attached to the top of the container, a propellant is injected into the container. For a 7 ounce container, 10-12 grams of a propellant such as butane is injected. To inject the propellant, the fill valve is unseated so propellant can flow into the chamber around the valve. The fill valve has a stem which fits through the opening, an inner sealing element formed on one end of the stem, and a “bowtie” section formed on the outer end of the stem. Opposed longitudinally extending grooves extend from the bowtie section along the side of the stem. During filling, a nozzle presses against the bowtie section of the valve and pushes the valve a sufficient distance inwardly that the butane can flow through the grooves into the chamber. In addition, pressure of the butane causes the valve to flex upwardly to create a larger opening for the gas to enter the container. When the nozzle is withdrawn, the pressure in the chamber now forces the inner sealing element of the fill valve against the inner surface of the container bottom, sealing the container. An example of this type of aerosol container is shown in co-assigned U.S. Pat. No. 5,915,595.
[0005] A second type container utilizes a piston disposed in the container with the product to be dispensed being on an outlet valve side of the piston, and the other side of the piston partially forming a propellant chamber in which the butane is injected. The propellant is introduced into the container through a fill valve fitted in the base of the container in the same manner as described above.
[0006] There are number of problems with current fill valves, both with respect to their design and manufacture. One significant problem occurs when a fill valve does not properly seal allowing propellant to leak out of the container subsequent to filling. Propellant leakage dramatically reduces the usefulness of a container to dispense product, and if enough propellant leaks out, the result is a “dead” container. A “dead” container is one on which, when the outlet valve is actuated, little or no product is dispensed. It will be understood that there is usually a significant time between when a container is filled and it is used. During this period when the container is being packaged, shipped, warehoused, sits on a shelf in a store, and finally purchased, any loss of propellant, however small, will affect the final usefulness of the can. It has been estimated that even a small leak can result in the loss of as much as 1 gm. of propellant a year.
[0007] Other, related problems occur during manufacture of the fill valve. Heretofore, fill valves have been made using a compression molding process which has been found to result in poor sealing because of poor cross-linking of the molded material during the manufacturing process, and compression setting. Cross-linking is the formation of chemical links between molecular chains in polymers. Compression set is a property of grommets that adversely affects their sealing capability. The result has been that even if a fill valve properly seals after filling; over time, propellant can still escape from the container because of poor compression set.
[0008] In addition to these factors, another factor causing poor sealing is the cryogenic process used to remove flash produced on a grommet during compression molding. After the molding process is completed, the fill valves are frozen and any extraneous material (the flash) is knocked or broken off the part. However, the freezing process can result in large and/or microscopic cracks being created in the grommet and these cracks become leakage paths for propellant to escape from the container.
[0009] It will be appreciated by those skilled in the art, that release of the propellant to the atmosphere adds to our environmental problems, regardless of how the propellant escapes. In addition, one “band aid” fix to loss of propellant is to inject more propellant into the container during filling than is otherwise needed, so even if some propellant escapes there is still sufficient propellant that product is adequately dispensed from the container. Further, manufacturers, fillers, or suppliers of the containers often have to replace “dead” containers adding to their warranty costs.
[0010] Another problem with previous fill valves has been that molded into each fill valve is indicia identifying the particular mold and mold cavity in which the fill valve is formed. This, of course, is to assist in trouble shooting if valves are found to be defective. Currently, this indicia is in the form of raised alphanumeric characters on one surface of the fill valve. It has been found that after manufacture, when the fill valves are placed on a conveyor which moves them to a container assembly station, the raised characters often cause the valves to not move smoothly along the conveyor, but rather more haphazardly. This can require additional manpower to insure that the fill valves do properly get to the assembly station and are properly oriented for insertion into the bottom of a container.
BRIEF SUMMARY OF THE INVENTION
[0011] The present invention is directed to an improved fill valve for use in an aerosol container to provide a better sealing capability. The fill valve is made using a flashless injection molding process rather than the compression molding process previously used. As part of this process, both the mold cavity and molding material are heated to elevated temperatures and this significantly improves the cross-linking which occurs during the molding process. Further, a section of the backside of the sealing area of the fill valve now has a recessed portion that improves flexing of the seal after propellant is injected into the container, thereby creating a more responsive seal. Information about the fill valve is now engraved on an out-of-the-way surface of the valve so to facilitate conveying of the valve during manufacture of a container.
[0012] This improved fill valve has a number of advantages over previous valves. One is a fill valve with more consistent dimensional and operational characteristics than previous fill valves. Importantly, the improved fill valve provides a more capable seal, and a valve less prone to the formation of leak paths through the valve. This significantly reduces the possibility of propellant leakage from a container, even containers with long shelf lives. This, in turn, reduces warranty returns and the associated costs of replacing a non-functioning or “dead” container. Additionally, because of the improved sealing capability, the reduction in leakage reduces pollution. It may also be possible to reduce the amount of propellant injected into a container during filling because, with less leakage, more propellant will remain in the container.
[0013] The elimination of unnecessary raised lettering also now makes it easier to handle and move significant volumes of fill valves during fabrication of a container.
[0014] Other objects and features will be in part apparent and in part pointed out hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0015] The objects of the invention are achieved as set forth in the illustrative embodiments shown in the drawings which form a part of the specification.
[0016] FIGS. 1A and 1B are simplified representations of aerosol container using an improved fill valve of the present invention;
[0017] FIG. 2 is a perspective view of the fill valve;
[0018] FIG. 3A is plan view of one end of the fill valve and FIG. 3B is a sectional view of the valve taken along lines 3 B- 3 B in FIG. 3A ; and,
[0019] FIG. 4 is plan view of the opposite end of the fill valve.
[0020] Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF INVENTION
[0021] The following detailed description illustrates the invention by way of example and not by way of limitation. This description will clearly enable one skilled in the art to make and use the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what I presently believe is the best mode of carrying out the invention. As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
[0022] Referring to FIG. 1A , an aerosol container 10 comprises a cylindrically shaped body 12 , a bottom, dome shaped end piece 14 , and an upper cap/valve assembly 16 . A product bag 18 is disposed in the container for dispensing a fluent product, and for this purpose, the container is filled with a propellant material, under pressure. End piece 14 has a central opening or aperture 20 formed in it, and a grommet or fill valve 22 of the present invention is seated in this opening to seal it. A propellant chamber 24 is formed in the lower end of the container and a propellant such as butane is injected into the container through valve 22 to pressurize this chamber during a filling operation.
[0023] In FIG. 1B , an aerosol container 30 comprises a cylindrically shaped body 32 , a bottom, dome shaped end piece 34 , and an upper cap/valve assembly 36 . A piston 38 is disposed in the container for dispensing the product, and again, the container is pressurized with a propellant material during a fill operation. End piece 34 has an aperture 40 formed in it and grommet or fill valve 22 is seated in this opening to seal it. A propellant chamber 44 is formed in the lower end of the container and the propellant is injected into the container through valve 22 to pressurize chamber 44 .
[0024] As shown in FIG. 2 , fill valve or grommet 22 comprises a unitary valve molded of a suitable elastomeric material in a multi-cavity mold. The valve is shown to have a first section 22 a , referred to as the “backend” of the valve, a central shaft section 22 b , and a head or “bowtie” section 22 c . Section 22 a is the greatest diameter portion of the valve. During fabrication of the container, the fill valve is pushed through opening 20 or 40 in the respective container 10 or 30 , from the inside of the container, using an appropriate tool. The “bowtie” section of the valve then projects through the respective opening to the outside of the container. The length of shaft 22 b is slightly greater than the thickness of the dome end of the container, so there is a slight play in the valve when first installed and before the container is pressurized with propellant.
[0025] A circumferential seal 46 is formed by the shoulder or rim portion of section 22 a which contacts or abuts against the inner face of the bottom 14 or 34 of container 10 or 30 . As noted, when the fill valve is first installed in the un-pressurized container, it fits loosely in place. However, after the container is filled with a propellant, the internal container pressure forces section 22 a of the fill valve tightly against the inner face of the container bottom. Seal 46 is now tightly pressed against this bottom wall surface of the container preventing leakage of propellant from the container.
[0026] On the other end 22 c of the fill valve, opposed grooves 48 a , 48 b are formed. The grooves extend longitudinally of section 22 c and into central shaft section 22 b of the fill valve. The grooves taper along the length of this section of the fill valve so that they terminate at the transition between this section and backend section 22 a of the valve. Section 22 c tapers outwardly from the outer end of the section to the abrupt transition between this portion of the fill valve and the section 22 b . A circumferential shoulder 50 is formed at the inner end of section 22 c where the transition occurs. During a container fill operation, a nozzle (not shown) is pressed against the outer end of section 22 c of the fill valve, forcing shoulder 50 against the outer face of the container bottom 14 or 34 . This action moves section 22 a of the valve away from opening 20 or 40 in the container. The grooves 48 a , 48 b formed in the fill valve now allow flow of propellant through opening 20 or 40 , into the propellant chamber 24 or 44 . When the nozzle is removed, the internal pressure in the container forces shoulder 46 of the valve to seal opening 20 or 40 as previously discussed.
[0027] The improved grommet or fill valve 22 of the present invention has a number of advantages of previous valves. One significant improvement is a better compression set from an increased cross-link density formed during the molding process and an improved elastomeric formulation. In the flashless injection molding process by which fill valves 22 are manufactured, the mold is maintained at a temperature necessary to cross-link the elastomer. The temperature of the elastomer injected into the mold to form the fill valves is at a temperature well above room temperature at the time of injection. In the fill valve of the present invention, the fact the mold and molding compound are heated to relatively high temperatures enhances the cross-linking process and substantially reduces the creation of leak paths. A particular advantage of the process by which the grommets are now made is that cryogenic deflashing of the fill valve is now unnecessary. Eliminating this manufacturing step prevents formation of cracks in the fill valve which could provide leakage paths for the propellant from the container in which the fill valve is installed
[0028] As shown in FIGS. 3A and 3B , an annular ring 52 is formed inwardly of the sidewall of section 22 a . Progressing further inwardly toward the center of the valve section, an annular raised section 54 is formed. Inwardly of section 54 is formed a section 56 which is stepped-down or recessed from section 54 by approximately 0.007″. The recessed section 54 provides a number of advantages to fill valve 22 over previous valves.
[0029] First, it provides an area by which the elastomer injected into a mold cavity can be readily injected without the gate for the cavity getting in the way of the flow of compound into the cavity.
[0030] Second, the recess reduces the amount of friction present during the feeding of the product on an assembly line.
[0031] Third, the undercut reduces the amount of material required to make the fill valve and results in a valve which is more flexible than previous fill valves. This makes the valve easier to handle and also helps it provide a better seal when a container is pressurized with propellant.
[0032] At the center of the section 54 is a depression or recess 58 . This recess is designed to receive the end of a tool (not shown) used to insert fill valve 22 in the opening 20 or 40 in an aerosol container during fabrication of the container. The valve is inserted by pushing against section 22 a so to force the outer, smaller diameter end 22 c of the fill valve through the opening.
[0033] Finally, previous fill valves had raised characters formed on the section 54 of the backside of the valve. As previously noted, this often complicated movement of the fill valves on a conveyor or inserting them into a container. Now, as shown in FIGS. 3A and 3B , the section 56 within annular ring 52 has pertinent information about the fill valve engraved on it. Specifically, this information identifies the mold and mold cavity in which the valve was formed. Such information is useful in analyzing productions problems which might occur so a mold or section of a mold which needs to be repaired or replaced is readily identified. Importantly, since this information is recorded in an out-of-the-way location but accessible location, this type of lettering is no longer required and the now “clean” surface of the backside of the fill valve makes it easier to handle the valve.
[0034] In view of the above, it will be seen that the several objects and advantages of the present invention have been achieved and other advantageous results have been obtained. | The present invention is directed to an improvement for a fill valve ( 22 ) for an aerosol container ( 10, 30 ) to provide better sealing capability. The fill valve is made using a flashless injection molding process in which both the mold cavity and molding material are heated to elevated temperatures to significantly improve cross-linking which occurs during the molding process. A backside ( 22 a ) of the fill valve now has a recessed portion ( 56 ) to facilitate ejection of the valve from a mold so leak paths are not created due to the forces applied to the valve during its extraction from the mold. The recessed portion reduces the amount of material required to make the fill valve and makes the fill valve flexible to aid in providing a good seal against leakage of a propellant from the container after filling. | 1 |
BACKGROUND
[0001] During test and assembly operations, semiconductor devices are subject to large amounts of mechanical and thermal stresses. This is particularly true of devices with increasingly finer feature sizes, as the propensity for intra- and inter-level shorts caused by such operations drastically increases. Devices that have been diced, tested and assembled in packages often show signs of stress-related failures. These may be small microscopic cracks or highly visible stress-relief mechanisms such as film delamination, buckling, cracking, etc. In such cases, devices damage and attendant loss of useful life, leads to increased replacement costs. Moreover, these cracks and deformation-induced defects are difficult to detect, requiring large amounts of exhaustive failure analyses.
SUMMARY
[0002] The inventors have realized that there is a need for a method of quickly detecting assembly and test-related deformation of a semiconductor device that requires minimal engineering effort. According to one embodiment, the subject invention pertains to a chip edge and/or corner distortion and damage detection circuitry. This circuitry will assist in alleviating and resolving stress-induced failures from test and assembly operations. According to one embodiment, the damage detection circuits are placed along the periphery and corners of each device and requires no special or additional processing steps, thus its placement on the chip does not add to manufacturing costs. The detection circuits may be placed in close proximity to the seal ring at the device edge and corners. The detection circuitry allows electrical testing of the device in both wafer and package form, thus permitting the engineer to singulate the location of stress-induced defects and deformation such as cracking, delamination etc.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 shows a top view of a semiconductor device comprising detection circuitry.
[0004] FIG. 2 is a magnified view of an embodiment of corner damage detection circuitry.
[0005] FIG. 3 shows a top view of a detection circuitry embodiment.
[0006] FIG. 4 shows a cross sectional view of along axis A-A in FIG. 3
[0007] FIG. 5 shows an isometric view of a serpentine circuitry embodiment.
[0008] FIG. 6 shows a serpentine circuitry embodiment. FIG. 6 a shows a cross-sectional view at the arrowed location in FIG. 6 b . FIG. 6 b shows a top plan view of a semiconductor device embodiment. FIG. 6 c shows a top plan view of the semiconductor device embodiment shown in FIG. 6 b at a level immediately beneath the level shown in FIG. 6 b.
DETAILED DESCRIPTION
[0009] According to one embodiment, the subject invention is directed to a semiconductor device comprising damage detection circuitry on at least a portion of a periphery of the semiconductor device. In a specific embodiment, the damage detection circuitry comprises one or more bands of conductive material disposed around the periphery of the semiconductor device. The detection circuitry is peripheral to the primary circuitry of the semiconductor device, and in those devices comprising a seal ring, inward from the seal ring.
[0010] Turning to the figures, FIG. 1 shows a top view of a semiconductor device 100 comprising four conductive bands 101 , 102 , 103 , and 104 around the periphery of the device 100 . Those skilled in the art will appreciate that the bands may completely follow the periphery or a portion of the periphery. Each of the conductive bands 101 , 102 , 103 and 104 are separately conductively connected to pads 111 , 112 , 113 , and 114 , respectively. The conductive bands 101 - 104 are not conductively connected to each other unless damage to the semiconductor device has occurred. This feature allows the testing for damage by applying a voltage or current to two or more of the pads 111 - 114 to measure change in resistance and/or determine if any short or open has occurred between any of the conductive bands 101 - 104 . A typical method of determining if any short has occurred is measuring any change in the initial resistance of the band (e.g. prior to assembly) comparative to post assembly and/or calculated values (pre and/or post assembly). Shorting of any of the bands is indicative of damage to the semiconductor device 100 , thereby enabling the engineer to diagnose and correct the cause of such damage. The semiconductor device 100 is comprised of alternating metallization layers and dielectric layers (not shown). Furthermore, the semiconductor device 100 comprises a primary integrated circuit 120 formed among such alternating layers. The conductive bands 101 - 104 are not conductively connected to the primary integrated circuit 120 and are positioned peripheral to said primary integrated circuit 120 . Surrounding the periphery of the semiconductor device 100 is a seal ring 125 .
[0011] The conductive bands 101 - 104 may be formed in multiple metallization layers and interconnected through vias in the dielectric layers. Therefore, testing of one band will enable the determination of damage present among any of the constituent layers. The configuration of the interconnected bands may take several forms, as will be readily appreciated by those skilled in the art in light of the teachings herein. In a specific embodiment, the configuration is a serpentine structure: that is, the individual band courses around the periphery at a first metallization layer and then connects to a band in a second metallization layer through one or more vias at a location along the band (typically at the end of the band), then courses around the second metallization layer and connects to a band on a third layer through one or more vias located at a location along the band, and so on, until a continuous serpentine like structure is constructed through the desired number of metallization layers. An example of a serpentine structure 500 is depicted in FIG. 5 . It is noted that the structure is not drawn to scale nor are the bends of the band for each layer shown. However, the important feature depicted in FIG. 5 is how the interconnected bands can form a continuous structure that may be formed around each metallization layer and are interconnected to lower metallization layers throughout the desired dimension of the semiconductor device. Furthermore, as depicted in FIG. 5 , the interconnection to other layers may be attained through one or more vias at any suitable location around the periphery.
[0012] Also shown in FIG. 1 is novel corner circuitry 140 and 145 in corners 1 and 2 , respectively, which enables particular sensitivity to cracks, deformations, and/or other damage at the corners of the semiconductor device 100 . As noted above, corner cracking can occur from excessive stresses typically induced in the chip during testing, wire bonding, flip chip bonding, underfill, molding and other assembly operations. The corner circuitry 140 comprises four separate triangular units 141 , 142 , 143 , and 144 .
[0013] FIG. 2 is a magnified view of the corner circuitry 140 shown in FIG. 1 . Each of the separate triangular units 141 , 142 , 143 and 144 are typically not conductively connected, but for damage to the corner 1 of the semiconductor device. Alternatively, those skilled in the art will appreciate that one or more of the units 141 - 144 may be connected to each other. Further, though not shown, the triangular units are typically conductively connected to triangular units on different metallization layers of the semiconductor device. This may be accomplished for example by way of a continuous serpentine structure similar to that shown and described for FIG. 5 , or by way of a via type like structure where vias along the length of the band connect a band on one metallization layer to another metallization layer (see, for example FIG. 4 ). It is also noted that the shape of the unit circuitry is not critical. Those skilled in the art will appreciate that the units may be configured as one of many different shapes including, but not limited, triangle, rectangle, square, or other polygonal shape, oval, circle, spiral, etc. The size of the shape can affect the level of resolution of the detection of mechanical problems. Typically, the smaller the size of the shapes the higher the resolution.
[0014] In the corner circuitry embodiment 140 shown in FIG. 1 , the units 141 - 144 are each individually connected to a pad 151 , 152 , 153 and 154 , respectively, formed on a top surface of the semiconductor device 100 . There may be one pad per unit as shown, or two or more pads per unit. Those skilled in the art will appreciate that as more pads are connected to different locations of the circuitry, this will enable a higher degree of accuracy for fault identification and the identification for fault isolation of the area or place of damage. Though not particularly shown in FIG. 1 , the units 141 - 144 of the corner circuitry 140 may be connected to units of the opposing corner circuitry 145 . Referring back to FIG. 2 , each of the triangular units 141 - 144 have a positive and negative lead (indicated by p and n). In a preferred embodiment, the p and n leads are each conductively connected to a pad on the semiconductor device 100 . In alternative embodiments, the individual triangular units may be individually or collectively connected to one or more bands.
[0015] FIG. 3 is top view of a semiconductor device 300 comprising an alternative embodiment of damage detection circuitry. The semiconductor device 300 comprises three conductive bands 301 , 302 , and 303 . The bands 301 - 303 are each conductively connected to a pad at each end: 311 a and b , 312 a and b , and 313 a and b , respectively. Furthermore, peripheral to the conductive bands is a seal ring 320 . The seal ring 320 is conductively connected to pad 321 . This configuration enables one to determine whether any damage has occurred between the seal ring 320 and one of the bands.
[0016] FIG. 4 represents a cross section of the bands and seal ring along the A-A axis in FIG. 3 . The seal ring 320 is shown as a series of bands 320 a - g formed in each metallization layer where each band is interconnected by a plurality of vias 322 . Conductive bands, 301 - 303 are shown as a series of bands 301 a - g , 302 a - g , and 303 a - g formed in each metallization layer and interconnected by a vias 323 , 324 , and 325 , respectively. The via structure provides a certain level of structural support and integrity. Thus, opens are not likely to occur, but shorts caused by leakage could still occur, and are detectable by the damage detection circuitry. Conductive bands 301 and 303 are free-floating i.e., they are not connected to the silicon base 330 of the semiconductor, whereas conductive band 302 is connected to the silicon base 330 . Therefore, the conductive bands 301 and 303 act as monitor bands, i.e.,enable testing for shorts that are indicative of damage. For example, when a tester is contacted with pad 312 and one of pads 311 and 313 , the presence of a short in the circuit may be determined. In addition, the location of the short may be further isolated by comparing the current that occurs on the (a) and (b) pads of 312 and 311 and/or 313 . Accordingly, bands 301 and 303 may be used to detect intralevel as well as interlevel opens and shorts. In an alternative embodiment, not shown, the metallization layers are of the conductive bands are not interconnected and each metallization layer of conductive bands are electrically connected to separate contact pads. This will further facilitate determining on which level(s) damage has occurred.
[0017] FIG. 6 a shows a cross section view of a semiconductor device 600 at the location indicated by the arrow in FIG. 6 b (see arrow). Each conductive band 601 , 602 , 603 , and 604 are a serpentine structure similar to that shown in FIG. 5 for one conductive band. Thus, at the cross-sectional location shown, there are no via-like structures interconnecting the bands at each level. In contrast, the seal ring 620 does comprise vias 622 that interconnect metallization layers. FIG. 6 b shows a top plan view of the semiconductor device showing conductive bands 601 - 604 . FIG. 6 c shows a top plan view of layer immediately below that shown in FIG. 6 b . The interconnections 611 , 612 , 613 , 614 of the conductive bands connecting the conductive bands of top metallization layer with that of the next lower metallization layer are visible at this layer. The vias 622 interconnecting the top metallization layer of the seal ring 620 are also visible at this layer.
[0018] While some embodiments of the present invention have been shown and described herein in the present context, it will be obvious that such embodiments are provided by way of example only and not of limitation. Numerous variations, changes and substitutions will occur to those of skilled in the art without departing from the invention herein. For example, the present invention need not be limited to best mode disclosed herein, since other applications can equally benefit from the teachings of the present invention. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims. | Disclosed herein are novel damage detection circuitries implemented on the periphery of a semiconductor device. The circuitries disclosed herein enable the easy identification of cracks and deformation, and other types of damage that commonly occur during test and assembly processes of semiconductor devices. | 6 |
BACKGROUND OF THE INVENTION
a. Field of Invention
This invention pertains to a device for exchanging data between two terminals simultaneously in both directions on one pair of wires.
b. Description of the Prior Art
Typically a relatively large computer installation or similar data processing center comprises one or more central computers which exchange data with a plurality of peripheral devices such as printers and so forth. Often these devices are several hundreds or thousands of feet away from the computer. Therefore it is common to use a local switching system in a star configuration for providing the means for said transmission. For relatively long transmission lines, duplex digital transmission of voice and data is fairly common. In such transmission various encoding schemes are used such as AMI and HDB-3. However because of actual length of these loops, various problems arise due to the long transmission times, signal attenuation, and reflection. Relatively expensive echo cancelling circuits are necessary to obtain acceptable signals. Furthermore these long loops preclude the use of a single power source for both the host and remote sets. Thus each set must be provided with its own power source.
In a full duplex mode two pairs of wires are commonly used to accommodate a digital signal exchange in two directions, each pair being dedicated to a direction. However providing four wires is rather expensive. Therefore two-wire systems have been proposed in which the wires are in effect dedicated consecutively for a first time interval to data communication in one direction, and for a second time interval they are dedicated to communication in the other direction. In this way messages are exchanged between the respective terminals in a ping-pong fashion. Of course in this configuration the overall data rate of the system can be maintained only by doubling the baud rate of the individual terminals.
OBJECTIVES AND SUMMARY OF THE INVENTION
An objective of the present invention is to provide a transmission system which makes use of two wires for simultaneous bi-directional digital exchange.
Another objective is to provide a system which receives its power from a single location. Other objectives and advantages shall become apparent in the following description of the invention.
A transmission system according to this invention comprises two terminals which are interconnected by a two wire loop. Each terminal is provided with a relatively simple lattice network adapted to separate received signals from the transmitted signals. A biphase encoding scheme is used with a zero D.C. level whereby a separate D.C. voltage may be connected across the two wires to be used as a power source without interfering with the data exchange.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the elements of the present invention; and
FIG. 2 shows a typical Manchester or biphase encoding scheme.
DETAILED DESCRIPTION OF THE INVENTION
The present system is intended for relatively short loops, in the order of 2000 feet, which are fairly frequent in private switching networks. Typically such systems tend to have a "star" configuration and do not need the bridged taps encountered in long, usually public, loops. Such short loops exhibit low loop attenuation, small reflections and since the resistive drop of the loop is relatively low power may be transferred from one end of the loop to the other.
As shown in FIG. 1, a digital transmission system comprises a host or master set 10, and remote set 12 interconnected by a loop of two wires 14, 16. In master set 10 digital signals are fed into an encoder 18 which generates a corresponding output signal on line 20. Preferably the signals are encoded by using any well-known biphase encoding schemes. One such scheme, known as the Manchester II Code is shown in FIG. 2. According to this code the encoded signal changes between two voltage levels V 1 and V 2 . The transition between these levels determines the digital bit that is being sent. For example, as shown in FIG. 2, a transition from V 1 to V 2 corresponds to binary "1" while a transition from V 2 to V 1 corresponds to a binary "0". The transition is timed to occur in the middle of the corresponding bit so that the resulting rectangular pulses have sufficient time to settle, thereby reducing the error rate of the scheme. Furthermore, in this particular application V 1 =-V 2 so that the average D.C. level of encoded signals is zero.
The output of encoder 18 is fed to a first amplifier 22. The same output is also inverted by inverter 24 and then fed to a second amplifier 26.
The two amplifier outputs are fed into an impedance network which may be in the form of a lattice network as shown in FIG. 1. The lattice network has two series arms Z 1 and Z 2 and two diagonal arms each comprising two resistors R4,R5 and R6,R7 respectively.
The central nodes E and F between resistors R4,R5 and R6,R7 respectively are used as inputs to a comparator 28. The lattice is used to transfer transmitted signals from the amplifiers to the transformer T1, and received signals from the transformer T1 to comparator 28. The selection criteria for these resistors are described later. The output of the lattice is connected across the primary coil of a two-to-four wire transformer T1. As shown, the two secondary coils of T1 are coupled by a capacitor C2 and are connected across wires 14,16 of the loop. The transformer is used to isolate the sets from the loop. The transformer also protects the sets from voltage spikes, while for the same time providing longitudinal balance for the loop. The remote set is essentially identical to the host set.
Z1 and Z2 are selected to present to the loop (after transformation by T1) a proper termination impedence of the transformer.
Theoretically it is possible to select the values of the resistors making up the diagonal arms of the lattice in such a manner that the input to the comparator 28 due to the outputs of amplifiers 22 and 26 is negligible. For example if R4=R7=2R 5 =2R6 the following conditions exist. The output of amplifiers 22 and 26 is given by V A =k and V C =-k. If Z 1 =Z 2 =Z is equal to the impedance of the loop then the transformer impedance is equivalent to 2Z and the voltages at modes B and D are given by V B =k/2 and VD=-k/2. Importantly, the input to transformer T1, V BD is equal to k. Assuming that the resistances of the diagonal arms is made larger than Z, elementary calculations show that V E =V F =0, nodes E and F being the nodes between resistors R4,R5 and R6,R7 respectively as shown. In other words, with no signals from set 12, the input to comparator 28 of set 10 is zero.
A similar analysis is performed for signals received from set 12. At set 12 if the output at nodes A, C is k, and -k respectively, then in set 12 the input voltage to the transformer is k. Therefore the voltage V BD across the primary coil of the transformer T1 corresponding to the signal from set 12 is equal to nk, where n is a function of the losses in the loop and the transformers. In general n is between 0 and 1 and typically n is between 0.5 and 1. Since the output resistance of amplifiers 22 and 26 is normally much lower than Z, V A '=V C '=0 and V B '=-V D '=nk/2
Therefore V F ' and V F ' are simply determined from the relationship
D.sub.F '=2R/3R×V.sub.B '=nk/3 and
V.sub.F '=2R/3R×V.sub.D '=-nk/3
Accordingly the voltage across the inputs of comparator 28 is 2/3 n k.
By superposition, the total voltage across the comparator inputs is equal to the sum of the effects of amplifiers from the two sets. However as shown above, the data transmitted from a particular set does not affect the corresponding comparator.
In practice, of course, perfect impedance matching is impossible. However for relatively short loops it was found that while the data signals are attenuated by a factor of two or less the error signals which result from the improperly matched lines including any echoes, are attenuated by a factor of five or more. The effects of these error signals can be reduced by a proper setting of the offset and hysterises of the comparator.
From the above description it is clear that the comparator of set 10 generates a train of digital encoded signals which is identical to the encoded signals generated by the encoder of set 12 and, vice versa, the comparator of set 12 generates a train of signals which is identical to the train of signals generated by the encoder of set 10. The sets can operate simultaneously on the same loop without interfering with each other. The output of comparator 28 is fed to a decoder 30 which then converts the train of encoded digital signals to a corresponding train of decoded signals. Of course the decoder 30 must be compatible with encoder 18, or in other words they both must use the same coding scheme.
As previously mentioned, the system of FIG. 1 preferable uses the biphase or Manchester II type of coding. However obviously other types of coding which allows clock recovery, minimizes the number of octaves of frequency range, and has no D.C. component, is also suitable. The last criteria is important because it permits the use of a single power supply to be used for both sets. For example, the output of 48VDC power supply could be connected across capacitor C 2 of set 10 (as shown in FIG. 1). Since the encoded data signals do not have a D.C. component they are not affected. At set 12 a D.C.-to-D.C converter 32 is provided which converts the 48VDC from the line to any required D.C. level(s). Thus the set 12 does not need its own power supply since it can be run from set 10.
In summary, in each set digital signals are encoded into a train of rectangular pulses which are transferred through a lattice and a hybrid transformer to the transmission lines. At the other end of the lines, the rectangular pulses are transferred through a corresponding transformer and lattice to a comparator. The comparator then generates a respective pulse train for decoding. Both sets are capable of transmitting and receiving data simultaneously over the transmission line so that full duplex simultaneous data exchange is achieved. | A duplex digital transmitter system is disclosed which permits simultaneous digital signal exchange over a two-wire loop. Two sets are provided at the ends of the loop, each having a three-port lattice adapted to separate the transmitted and received digital signals. The digital signals are encoded using a biphase scheme so that they have a zero D.C. component. Therefore the loop is used simultaneously to transmit D.C. power from one set to the other. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to a gradient coil system suitable for use in a nuclear magnetic resonance tomography apparatus.
2. Description of the Prior Art
Gradient coil systems are required in nuclear magnetic resonance tomography devices for generating gradient fields in the x-direction (G x ) and in the y-direction (G y ). It is known to provide a hollow cylindrical carrier having a cylinder axis proceeding in the z-direction of a rectangular x-y-z coordinate system, with the origin of the coordinates disposed in the center of the imaging region. A fundamental magnetic field B z is also generated, which is oriented in the z-direction. It is known to provide a set of 4 coils for generating the G x gradient and a separate set of saddle coils for G y gradient. Each saddle coil has straight conductor sections, connecting conductor arcs, with the straight conductor sections being oriented along the z-direction so that each saddle coil generates a gradient field in the same volume as the fundamental magnetic field. The straight conductor sections may be arranged in the winding bed of a carrier.
In nuclear magnetic resonance devices of this type, it is known that the fundamental magnetic field aligns the nuclear spins in an examination subject, such as a human body, and an RF system is provided for generating an RF field to excite nuclear spins in the examination subject, and to receive the resulting nuclear magnetic resonance signals. Gradient coils which proceed in the direction of the fundamental field generate a linearly changing magnetic field in this direction, and are required for the slice selection and for the spatial allocation of the signals in the slice. Further gradient coils similarly generate a magnetic field proceeding in the direction of the fundamental field but which changes in two directions perpendicular thereto. By selective excitation of these gradient coils, the phase of the RF signal can be influenced, so that an image of the slice plane of the examination subject can be derived based on the nuclear spin distribution.
A known nuclear magnetic resonance tomography device includes a system of gradient coils which simulate a hollow cylinder having a radius R, and having a cylinder axis proceeding in the z-direction of a rectangular x-y-z coordinate system having the coordinate origin in the center of the imaging region. The fundamental magnetic field B z also is oriented in this direction. At least two annular individual coils arranged symmetrically relative to the x-y plane, and oppositely traversed by current, are provided for generating a field gradient G z , in the same direction as the fundamental field which is approximately constant in the imaging region. In this known system, further gradient coils are provided for generating the y-gradient G y and the x-gradient G x . Respective sets of coils, each consisting of a set of 4 saddle-shaped coils, are provided for respectively generating these gradients. Each pair is respectively arranged symmetrically relative to the x-y plane, which is also the imaging plane of the tomogram to be produced. These saddle coils generate a field gradient in the x-direction ##EQU1## which is substantially constant in the imaging region, and generate a corresponding field gradient in the y-direction ##EQU2## The saddle coils each contain straight conductor sections proceeding in the z-direction, and contain conductor arcs parallel to the x-y plane which extend around the circumference of an imaginary cylinder. The directions of current conduction in the adjacent straight conductor sections of the two individual coils of each coil pair are the same. The directions of the current, however, are opposite in the conductor sections arranged symmetrically relative to the x-y plane. The conductor arcs of the saddle coils facing toward the x-y plane are each divided so that a further conductor arc arises. The conductor arcs are arranged at predetermined distances from the x-y plane and the coupling between the conductor arcs increases with increasing distance from this plane. Such an arrangement is described in U.S. Pat. No. 4,486,711.
Given the use gradient coils in a nuclear magnetic resonance tomography apparatus for fast pulse sequences, the share of the higher audio frequencies from about 1 kHz through 10 kHz which is contained in the spectrum of the pulse sequences increases. To avoid both an increased power consumption and field distortions in this range due to the skin effect in solid conductors, stranded or cable conductors are used for the windings of the gradient coils. The individual saddles of a coil set of the gradient coils for a predetermined spatial coordinate must be connected to one another along short paths exhibiting low inductance. Because cable conductors contain individual wires insulated from each other, a solid block of solder, which can cause disturbing eddy currents, must be used to provide an electrical connection at the conductor ends.
Another known gradient coil system for use in a nuclear magnetic resonance tomography apparatus is described in European application 0 274 149. This known gradient coil system is arranged on a hollow cylindrical carrier having a cylinder axis proceeding in the z-direction of a rectangular coordinate system having the coordinate origin in the center of the imaging region. The fundamental magnetic field is also oriented in the z-direction. A coil set consisting of four saddle coils is provided for generating the x-gradient, and another set of four saddle coils is provided for generating the y-gradient. Each saddle coil consists of three sub-coils which are arranged on the same cylindrical surface. The conductor arc of the outer sub-coil and the conductor arc of the middle sub-coil proceed close to the symmetry plane z=0, whereas the conductor arc of the inner sub-coil is farther from this plane. One conductor arc of the middle sub-coil contains a concave curvature. This coil system can thus not be wound without substantial outlay.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a winding and circuit diagram for a gradient coil system having saddle coils which can be manufactured in a simple manner and which permits a plurality of pairs of saddle coils to be wound without intermediate contacts.
The above object is achieved in accordance with the principles of the present invention in a gradient coil system having a set of four saddle coils for generating the x-gradient and another set of four saddle coils for generating the y-gradient. Each coil set is arranged in a respectively different cylindrical surface, defined by a carrier member. The saddle coils in each set are each composed of three sub-coils, the sub-coils for the x-gradient being arranged in a first cylindrical surface, and the sub-coils for the y-gradient being arranged in a different cylindrical surface. The three sub-coils of each saddle coil are formed by a cable conductor and are exclusively wound with convex curvature. The arc conductors of the middle sub-coils facing toward the plane z=0 have a shape which approximates an arc of an ellipse.
In the gradient coil system disclosed herein, the individual saddle coils contain only rounded corners and only convex bends of a common flexible cable conductor. The individual saddle coils are preferably formed by sub-coils which are helically wound. The number of turns of these sub-coils is preferably in a ratio of 1:1:4 from the outer to the inner sub-coil.
The arrangement of the connecting lines of the individual saddle coils to one another is preferably such that the lead to one of the saddle coils provides a bifilar conductor arrangement which can be tapped. These conductor portions thus do not generate disturbing stray fields. The saddle coils for the x-gradient are preferably arranged in a further cylindrical plane having a slightly enlarged diameter, and can be offset by 90° relative to the coil set for the y-gradient in a known manner. The arrangement for the x-gradient is preferably selected so that the underpasses for the leads to the individual saddle coils are respectively situated at a location of the cylindrical surface at which a coil portion of the y-gradient is not present.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an end view, seen in the direction of the z-axis, of a gradient coil system for the x-gradient and for the y-gradient constructed in accordance with the principles of the present invention.
FIG. 2 is a plane view of the structure of the portion of the gradient coil system for generating the y-gradient constructed in accordance with the principles of the present invention using saddle coils.
FIG. 3 is a plane view of the structure of the portion of the gradient coil system for generating the x-gradient constructed in accordance with the principles of the present invention using saddle coils.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the embodiment of gradient coil system shown in FIG. 1, each set of gradient coils for respectively generating the x-gradient and y-gradient consists of four saddle coils, with only two of those saddle coils being visible in FIG. 1. Two such saddle coils 2 and 3 can be seen in the drawing, which are part of the set of coils for generating the y-gradient G y in the direction of the y-axis of a rectangular coordinate system, on which the x-axis is also shown in FIG. 1. The saddle coils 2 and 3 are disposed opposite one another in the winding bend of a hollow cylindrical carrier member 6, indicated in dot-dash lines. The fundamental field of a nuclear magnetic resonance tomography apparatus in which the gradient coil system is to be used proceeds in the z-direction (i.e., in and out of the page) of this coordinate system. The conductors 2 and 3 are equidistantly spaced from the x-z plane, with the length of the arced portions of the saddle coils 2 and 3 being selected so that an angle φ is formed with the x-z plane.
A gradient system for generating the x-gradient is also shown in FIG. 1, of which two coils 52 and 53 can be seen. The coils 52 and 53 are also wound in the winding bed of the carrier member 6. The coils 52 and 53 are wound on an imaginary cylindrical surface of the carrier member 6 which is slightly spaced from the imaginary cylindrical surface in which the coils 2 and 3 are wound. The spacing between the two different cylindrical surfaces in shown enlarged in FIG. 1 for clarity.
The coil set for generating the y-gradient is shown in plan view in FIG. 2, in which the further saddle coils 4 and 5 can be seen in addition to the saddle coils 2 and 3. Each pair of saddle coils is arranged symmetrically relative to the plane z=0. This is also the imaging plane for the production of a tomogram.
In the following explanation of the arrangement of the cabled conductor 10 which forms the coils, the various positions of the common conductor 10 which forms the coils 2, 3, 4 and 5 are indicated only by directional arrows, which also represent the direction of the current when the gradient coils are operated. A feeder 24 of the conductor 10 is slightly offset from the plane φ=0°. The conductor 10 makes an underpass at the location 25, indicated by dot-dash lines, which can be achieved by an appropriate depression in the winding bed of the carrier 6. Following the underpass, the sub-coil 11 is wound which may, for example, consist of 16 turns, and which represents the inner sub-coil of the saddle coil 2. This coil is composed only of straight conductors in the z-direction, and of arced conductors in the circumferential direction of the carrier 6. The turns of the sub-coil 11 are all arranged in the same cylindrical surface of the carrier member 6. After completing the sub-coil 11, a further sub-coil 12 (the middle sub-coil) is formed having, for example, four turns beginning at position 26. The arced conductors of the sub-coil 12 are approximated by an arc of an ellipse at the location 27. These windings also lie in the same cylindrical surface.
After producing, for example, four turns, a transition to a new sub-coil 13, which may also have four turns, takes place at the position 28. The arced conductors of this sub-coil 13 facing toward the imaging plane z=0 have only a curvature in the circumferential direction of the carrier member 6 at the position 29.
After the production of the sub-coil 13, the conductor 10 is bent at the position 30 and is supplied to the saddle coil 3 via an underpass in the region of the position 31. The inner sub-coil 14 of the saddle coil 3 may also consist of 16 turns. At the position 32 after the completion of these 16 turns, a transition to a further sub-coil 15, which may have four turns, and to a sub-coil 16, which may also have four turns, occurs.
After the completion of the saddle coil 3, a tap is made at the location 33, and a transition occurs at the position 34 to the cylindrical surface of the carrier member 6 over the plane φ=0° and the feed to the saddle coil 4 is undertaken at the position 35.
In the region of the position 36, the underpass of the conductor 10, in an appropriate depression of the winding bed of the carrier member 6 again shown with dot-dash lines, occurs. After the production of an inner sub-coil 17 having, for example, 16 turns, the transition is made to the second sub-coil 18, having four turns, at the position 37. Subsequently the transition to the sub-coil 19, which may also have four turns, occurs at the position 38. After the tap at the location 39, the feed to the saddle coil 5 is undertaken an underpass in the region of the location 40.
After the production of an inner sub-coil 20, the transition to the second sub-coil 21, having four turns, again occurs at the position 41, and subsequently the transition to the third sub-coil 22, which may also have four turns, takes place at the position 42.
After the production of the saddle coil 5 having its outer sub-coil 22, a tap at position 44 is made from the coil proceeding from position 43, and the return from the saddle coils 2-5 for the y-gradient is made at the position 45.
On a spherical surface having the standardized radius r=R a /R G = 0.5 of the radius of the carrier member 6, the embodiment of the saddle coils 2-5 produces distortions of the tomogram in the x-y plane of less than 1%. Extremely low disturbances of B (5,5)= -0.27% and B (7,1)=0.1% arise by rounding the calculated values to the whole numbers of turns.
In this embodiment of the saddle coils 2-5 for the y-gradient, addition disturbing fields cannot arise either at the feed and tap at the positions 24 or 25, nor due to the connecting lines at the positions 33 and 34 and at 35 and 39, because there is antiparallel (i.e., opposite direction) current conduction. Due to the winding of the four saddle coils 2-5 from a common cable conductor 10, losses due to eddy currents in solid conductor connections are not generated. Because the sub-coils of the saddle coils 2-5 are only composed of straight conductors and arc conductors having the same curvature, and since the arc of the sub-coils 12, 15, 18 and 21 facing toward the imaging plane can be calculated by the approximation of an ellipse, both a simple calculation and a simple manufacture of these saddle coil pairs result.
As shown in FIG. 3, two further saddle coils 54 and 55 are provided for generating the x-gradient in additional to the saddle coils 52 and 53. The saddle coils 52-55 each consist of three sub-coils, the totality of sub-coils be referenced 61-72 in FIG. 3. The windings proceed as described in detail above in connection with the coils for generating the y-gradient. As can be seen in FIG. 3, the feeder 81 and the return 82, as well as the connecting lines between the coils at 83 and 84, 85 and 86, and 87 and 88 are bifilarly arranged with oppositely directed current conduction. The underpass of the feeder to the inner sub-coils 61, 64, 67 and 70 is undertaken at respective locations 91, 92, 93 and 94 on the circumference of the carrier member 6 at or in the proximity of the plane φ=0° at which the gradient coils 2 and 3 for the y-gradient are not present. Only a single, additional cylindrical surface on the carrier member 6, whose diameter is not significantly larger than the diameter for coil system consisting of the saddle coils 2-5 for the y-gradient, is thereby required for the saddle coils 52-55 for the x-gradient. This is of particular advantage because the reactive power consumption of the gradient coils increases with the fifth power of the radius.
A common hollow cylindrical carrier member 6 is described above as being provided for the two sets of gradient coils. It is also possible, however, to provide a separate carrier member under certain conditions for each of the two coil sets.
Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventors to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of their contribution to the art. | A gradient coil system for a nuclear magnetic resonance tomography apparatus has a set of saddle coils disposed on a first cylindrical surface for generating the x-gradient, and a set of saddle coils disposed on a second, separate cylindrical surface for generating the y-gradient. The saddle coils in each set include three sub-coils having predetermined ampere turns, and formed by cable conductor wound exclusively by convex turns arranged in the same cylindrical surface. A middle coil of the three sub-coils has an arced portion facing the z═0 plane in an x-y-z coordinate system which approximates an arc of an ellipse. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a division of application Ser. No. 09/321,496, filed May 27, 1999, now U.S. Pat. No. 6,358,276, which claims the benefit of U.S. Provisional Application No. 60/105,768, filed Sep. 30, 1998, each of which are incorporated fully herein by reference.
FIELD OF THE INVENTION
The present invention relates generally to endoluminal devices, and more particularly to stents.
BACKGROUND OF THE INVENTION
Stents and similar endoluminal devices have been used to expand a constricted vessel to maintain an open passageway through the vessel in many medical situations, for example, following angioplasty of a coronary artery. In these situations, stents are useful to prevent restenosis of the dilated vessel through proliferation of vascular tissues. Stents can also be used to reinforce collapsing structures in the respiratory system, the reproductive system, biliary ducts or any tubular body lumens. Whereas in vascular applications fatty deposits or “plaque” frequently cause the stenosis, in many other body lumens the narrowing or closing may be caused by malignant tissue.
Fluids have traditionally been used to pressurize the angioplasty balloons used to open restricted vessels. The balloons may have a variety of shapes including a coiled form. In such a device fluid is injected into the balloon to inflate the device and maintain turgidity. Shturman (U.S. Pat. No. 5,181,911) discloses a perfusion balloon catheter wound into a helically coiled shape with one end attached to a fitting and the other to a syringe for inflating the balloon with fluid. When the balloon is inflated, its coiled form allows blood flow thorough the open center of the structure. At the same time it is possible to actually have fluid flow within the balloon structure so that the syringe can deliver fluid into the balloon, fluid can flow through the balloon, and fluid can then exit through a second lumen in a catheter attached to the syringe.
Coiled stents that are connected to a catheter apparatus, as in Wang et al. (U.S. Pat. No. 5,795,318), are used for temporary insertion into a patient. Wang et al. discloses a coiled stent of shape-memory thermoplastic tube that can be converted from a relatively narrow diameter to a larger coiled form by heating. The narrow diameter coil is mounted at the end of a catheter over a balloon and in a preferred embodiment a resistive heating element runs down the length of the thermoplastic element. An electric current is applied to heat the element thereby softening it while the balloon is expanded to enlarge the diameter of the coil. Upon cooling the enlarged coil hardens and the balloon is withdrawn. After the temporary stent has performed its duty, it is again heated and removed while in the softened state. In one embodiment the thermoplastic tube is supplied with an additional lumen so that liquid drugs can flow into the stent and delivered through apertures or semi-permeable regions.
The attempt to kill or prevent proliferation cells is a common theme in clinical practice. This is generally true in vascular and non-vascular lumens. It is known that ionizing radiation can prevent restenosis and malignant growth. Although the effect of temperature extremes, e.g., cryogenic (cold) or hot temperatures, on cellular activity is not as well researched, it may provide a safer approach to control of tissue proliferation. Among the drawbacks of the prior art coiled balloons is that the balloon material is relatively weak so that expansion and contraction cause the balloon to fail. Failure of a balloon containing radioactive or cryogenic fluids could be catastrophic. It would be desirable to provide a catheter based, minimally invasive device for stenting support that could deliver hot or cryogenic or radioactive fluids or drugs and that would be sturdy and could remain in the body for extended periods of time, detached from the insertion device.
BRIEF SUMMARY OF THE INVENTION
In its simplest embodiment the present invention is an endoluminal coil stent comprising a hollow tube formed into a series of loops or other known stent shapes which initially has a low profile and diameter. This structure can be delivered into a patient's vascular system and expanded to full size. The present invention to provides a stent that is hollow allowing the passage of fluid. The stent has either one or a plurality of passageways for fluid flow. The stent is attached to a catheter via a special fitting so that when engaged with the catheter, fluid flows freely from the catheter to the stent with a possible return circuit through the catheter. When disengaged, the fitting prevents leakage from the stent permitting the stent to remain in place in a patient's vasculature.
This invention provides a way of treating vascular areas affected with malignant growths or experiencing restenosis from smooth muscle cell proliferation, etc. The stent is inserted in a small diameter configuration and after being enlarged to a larger diameter, acts as a support device for the areas of restenosis or malignant growth. In addition, the stent can treat these affected areas in a unique way by flowing radioactive, heated or cryogenic fluids through the stent.
The present invention also provides a way of delivering drugs to an affected site. A stent to accomplish this purpose can be composed of several different materials. For example, the stent can formed from a metal or other material with small pores machined or otherwise formed (e.g., with a laser). When such a stent is filed with a drug, that drug slowly disperses through the pores. Alternatively, an entire metal tube or portions of the tube could be formed e.g., from sintered metal powder thereby forming a porous structure for drug delivery. Another embodiment would alternate a metal tube (for structural stability) with dispensing segments inserted at various intervals. The segments would be perforated to allow seepage of the drug or would be otherwise formed from a porous material. Another embodiment employs an expanded polytetrafluoroethylene (PTFE) tube around a support wire or metal tube in the form of a coiled stent so that a hollow passageway is created between the metal and the PTFE. A drug is flowed into this space and slowly dispensed through the porous PTFE.
One embodiment of the hollow stent of the present invention comprises a shape memory metal such as nitinol. Shape memory metals are a group of metallic compositions that that have the ability to return to a defined shape or size when subjected to certain thermal or stress conditions. Shape memory metals are generally capable of being deformed at a relatively low temperature and, upon exposure to a relatively higher temperature, return to the defined shape or size they held prior to the deformation. This enables the stent to be inserted into the body in a deformed, smaller state so that it assumes its “remembered” larger shape once it is exposed to a higher temperature (i.e. body temperature or heated fluid) in vivo.
Special fittings are incorporated at the ends of the hollow stent. These fittings facilitate the injection and removal of fluid and also allow the stent to be detached from the insertion device to be left in place in a patient. The hollow stent has an inlet and an outlet so that a complete fluid path can be created, and fluid can be continually circulated through the stent. In the simplest configuration the inlet and outlet are at opposite ends of the stent. However, if the stent is equipped with a plurality of lumens, two lumens can be connected at a distal end of the structure so that the outlet and inlet are both together at one end. Other arrangements can be readily envisioned by one of ordinary skill in the art.
The stent is inserted into the body while connected to a catheter in a small, deformed state. Once inside the patient's body the stent is advanced to a desired position and expanded to its larger full size. If the stent is composed of shape memory metal, for example, the stent expands from its small-deformed state to its remembered larger state due to the higher body temperature or due to the passage of “hot” fluid through the stent. Subsequently “treatment” fluid (e.g., heated, cryogenic or radioactive) is pumped through the catheter to the stent where it is circulated throughout the stent, treating the adjacent vascular walls. The catheter can either be left in place for a certain period of time or removed, leaving the fluid inside the stent. This would particularly be the case with radioactive fluid or with a porous drug delivery stent.
The stent can be removed by reattaching the catheter allowing one to chill and shrink the stent (in the case of a memory alloy). Alternatively, the device can readily be used in its tethered form to remove memory alloy stents of the present invention or of prior art design. For this purpose a device of the present invention is inserted into the vasculature to rest within the stent to be removed. Warm fluid is then circulated causing the stent to expand into contact with the memory alloy stent that is already in position. At this point cryogenic (e.g., low temperature) fluid is circulated causing the attached stent and the contacted stent to shrink so that the combination can be readily withdrawn.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a hollow coiled stent.
FIG. 2 is a perspective view of a valve assembly to be used with FIG. 1 .
FIG. 3 is a sectional view of the hollow stent tube of FIG. 2 .
FIG. 4 is a representation of the stent of FIG. 1 in the position for treatment.
FIG. 5 is a sectional view of a second embodiment of a hollow coiled stent.
FIG. 6 is a perspective view of a second embodiment of a hollow coiled stent.
FIG. 7 is a perspective view of a third embodiment of a hollow coiled stent.
FIG. 8 is a perspective view of a valve assembly to be used with FIG. 6 .
FIG. 9 is a perspective view of a fourth embodiment of a hollow coiled stent.
FIG. 10 is a sectional view of the hollow stent tube of FIG. 8 .
FIG. 11 ( 11 a , 11 b , and 11 c ) is an illustration of the method detailed in FIG. 12 .
FIG. 12 is a flow diagram explaining use a stent of the present invention to retrieve a shape memory stent already in place.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, in which like reference numbers represent similar or identical structures throughout the drawings, FIG. 1 depicts a preferred embodiment of this invention. Pictured in FIG. 1 is a medical apparatus 10 comprising an endoluminal stent 20 attached to a delivery catheter 30 by means of a valve assembly 40 . In this representation endoluminal stent 20 is generally coiled in shape leaving a tubular space down the center of its length. Obviously, the principle of a hollow stent can be applied to stents of a zigzag or other construction other than simply coiled. The tubing 22 of the stent 20 is preferably composed of a metal material that can be crimped onto a balloon catheter (not shown) for insertion into a body. Once positioned inside of the body at the desired location, the balloon can be inflated, bringing the stent from a compact small size to its enlarged full size thus opening a pathway for blood flow.
Inside the tubing 22 of stent 20 , two fluid pathways exist. These pathways can be seen in the cross sectional view of FIG. 3 . Pathways 26 and 28 have opposite flowing fluid streams and connect at the distal end 24 of stent 20 . By allowing for opposite streams, radioactive, heated or cryogenic liquids can continuously flow through stent 20 for the purpose of killing or preventing proliferation of cells. By “heated” or “hot” is meant temperatures above body temperature. By “cryogenic” or “cold” is meant temperatures below body temperature. The stent 20 can either remain connected to a delivery catheter 30 for temporary insertion, or be detached for a more permanent insertion. In either case, fluid flow can be circulated throughout stent 20 prior to disconnection. In the simplest design, fluid passageways connected to the stent 20 are lumens of the delivery catheter so that when the catheter is withdrawn, fluid flow must cease. It is also possible to provide separate flexible tubes that are threaded through the catheter so that the delivery catheter can be withdrawn leaving the relatively smaller fluid delivery tubes (not shown) behind. Preventing leakage of the fluid from the stent 20 after the catheter 30 is disconnected is accomplished through a valve mechanism contained in the catheter 30 , or the stent 20 and/or both. In the example illustrated in FIG. 2 rubber or elastomer diaphragms 25 are penetrated by small hollow needles 48 in the valve assembly 40 . In addition, the valve 40 may comprise a simple back flow preventer. Thus, when pressure is applied from incoming fluid to the valve assembly 40 , a ball 45 which sits in a ball seat 44 is forced back against a spring 46 and the valve 40 opens for the incoming fluid pathway 28 . A similar arrangement allows pressure to open the outgoing fluid pathway 26 . A check ball valve is shown only as an example. Flap valves or any of a number of other back flow valve designs well known in the art can be employed. Complex systems in which a bayonet-type attachment automatically opens a valve are also possible.
The catheter 30 comprises a catheter shaft 32 , which further contains two fluid pathways 34 and 36 as seen in FIG. 2 . At the distal end of catheter 30 , the valve assembly 40 has small hollow needles 48 that are designed to puncture elastomer diaphragms 25 . The catheter 30 is slightly larger in diameter than the stent member 20 so that the catheter tubing wall 32 forms a friction fit over the stent wall 22 . This creates a seal between the catheter 30 , and the stent 20 for fluid delivery and removal. Upon detaching the catheter 30 leakage from the stent 20 is prevented due to the self-healing properties of the diaphragms 25 . Obviously, the back flow preventer 40 could be on the stent 20 and the diaphragms could be on the catheter 30 .
As discussed above, stent 20 is inserted into the body to the desired site through the use of a catheter insertion device well known in the art. FIG. 4 depicts stent 20 in its enlarged form after it has been inserted into the body at the affected location and expanded. Other means of stent expansion other than a balloon catheter are possible. If the stent 20 is formed from shape memory metal, such as Nitinol, the heat of the body can cause the stent 20 to assume a larger, remembered form. Alternatively, heated fluid can be circulated through the stent to cause it to recover its remembered form. A self-expanding stent made of a spring-type alloy can also be employed. In that case the delivery catheter would be equipped with means (e.g., an outer sheath) to keep the stent compressed until it was at the desired location.
By increasing the diameter of stent 20 at an affected location, the passageway is enlarged to permit increased blood flow. At the same time, fluids can pass through the interior of tubes 22 of the hollow stent 20 to treat the vascular wall. The walls of the vasculature can be treated by running either a radioactive, cryogenic or heated fluid through the stent 20 or by delivering a drug through a stent equipped for drug diffusion (e.g., through holes or a porous region).
FIG. 5 depicts a second embodiment of the invention. In this embodiment, the hollow stent 60 has only one fluid pathway 66 , an inlet without an outlet, and is used to deliver drugs to affected areas. Once the stent 60 is inserted into place and is in its enlarged configuration, drugs are delivered through the catheter to the stent 60 . Stent 60 can be constructed in various ways to facilitate the delivery of drugs. In one case, as shown in FIG. 6, the stent 60 is constructed with regions or segments that have pores 64 to allow drug seepage from the tubing 62 . Alternatively, continuously porous metal, porous plastic, or a combination of metal and plastic can be used. The perforations 64 or slits in the stent to facilitate drug delivery must be of sufficiently small size to allow the passage of the drug through the entire length of the stent so that all areas can be treated. It will be apparent that pore size can control the rate at which the drug is dispensed. It is possible to cover the pores 64 with semi-permeable membrane to further control and restrict drug outflow. A semi-permeable membrane with inclusion of an osmotic agent with the drug will result in water uptake and more rapid and controlled pressurized delivery of the drug.
A third embodiment of the invention, FIG. 7, has a hollow stent 70 containing a single fluid pathway. The tubing 72 can be made of any of the materials discussed above, but in this embodiment, the stent 70 has an inlet path 78 that carries the fluid to the distal end 74 of stent 70 where it then runs through the coils. In this embodiment, a valve 80 connects the stent 70 to catheter 30 . FIG. 8 shows a cross-sectional view of valve 80 . The pressure from the liquid sent through the catheter causes the gate 82 of valve 80 to open to allow the fluid into the inlet path 78 . The pressure that forces the opening of gate 82 causes the simultaneous opening of gate 84 , allowing the fluid that is circulated through the stent 70 to exit through pathway 36 of catheter 30 . The fluid entering and exiting through catheter 30 must also go through a check ball valve assembly similar to the one shown in FIG. 2 . Again, flaps or other “one way” valve mechanisms can be applied. After all incoming fluid has been delivered to the stent 70 , the absence of pressure causes gate 82 and gate 84 to close, thereby closing valve 80 . This design can be used with any of the fluids mentioned above. The stent 70 can be used to circulate radioactive or cryogenic fluids for treatment of the vascular walls and can also be perforated for the delivery of drugs.
In a fourth embodiment, a hollow coiled stent 90 is formed from polytetrafluoroethylene (PTFE) 92 . In FIG. 9, a perspective view of this embodiment can be seen. The stent 90 consists of a support wire 94 over which PTFE 92 is fitted. The pliable structure resulting is then formed into a coiled stent. The PTFE 92 is fitted around the wire 94 so that there is sufficient room to allow the passage of fluid. FIG. 10 shows a cross-sectional view of stent 90 , illustrating the pathway 96 created around the support wire 94 to allow the passage of fluid. In this embodiment, stretched expanded PTFE can be used to create a porous stent to facilitate the delivery of drugs. The wire 94 can also be hollow (passageway 95 ) so that the stent 90 can simultaneously deliver drugs and radioactive fluid or temperature regulating fluid.
A fifth embodiment of the invention is illustrated in FIG. 11 and described in a flow diagram shown in FIG. 12 . This embodiment is a method for recapturing an existing shape memory metal stent already in the body. With reference to both FIGS. 11 and 12, a shape memory metal stent A is inserted into the body in its small, deformed state through the use of an insertion device well known in the art in step 112 . The inserted stent A in its deformed state is placed into the center of a memory alloy stent B that is already in an enlarged support position in the body in step 114 . The deformed stent A is then enlarged so that it comes in contact with stent B. This can be accomplished in one of two ways. Either the stent A may enlarge due to the higher in vivo body temperature in step 115 , or a hot liquid may be pumped through stent A to cause it to expand in step 116 . Once expanded and in contact with stent B, cryogenic liquid may be pumped through stent A so that both stent A and stent B are chilled and either shrink down to their deformed states or become sufficiently relaxed to allow ready removal in step 118 . Once in a small, deformed or relaxed state, stents A and B are easily removed from the body in step 119 by withdrawing the catheter attached to stent A. FIG. 11 a illustrates stent A in its reduced state being inserted into stent A. FIG. 11 b shows an enlarged version of stent A contacting stent B. Thereafter, a temperature change caused, for example, by fluid circulating through stent A will shrink both stents and enable their removal (FIG. 11 c ).
Having thus described a preferred embodiment of a hollow endoluminal stent, it should be apparent to those skilled in the art that certain advantages of the within system have been achieved. It should also be appreciated that various modifications, adaptations, and alternative embodiments thereof may be made within the scope and spirit of the present invention. For example, a hollow stent with a coiled, tubular shape has been illustrated, however, many other possibilities exist for the shape and size of the hollow stent. In addition, the passageways are illustrated as round but could take on a variety of other shapes. The described embodiments are to be considered illustrative rather than restrictive. The invention is further defined by the following claims. | An endoluminal stent contains a hollow passageway for the circulation of fluids to treat vascular walls affected with malignant growths or experiencing restenosis. The hollow passageway stent can have one or a plurality of passageways and is configured in a tubular shape with numerous coils, providing an empty tubular lumen through the center of the stent to allow blood flow. The stent is connected to a removable catheter that conducts fluid to the stent. Fluid flow may be regulated by valves incorporated in either the stent and/or the catheter. The stent and catheter are connected to avoid leakage of the fluid. Cryogenic, heated or radioactive fluids are circulated through the stent to treat the affected sites. A method of delivering drugs to the vascular wall is also provided by creating a stent with porous outer walls to allow diffusion of the drug. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates generally to a method and system of improving silhouette appearance, applied to a bump mapping technique, thereby rendering a three-dimensional and true object silhouette.
[0003] 2. Description of the Related Art
[0004] Bump mapping roughens surfaces of a object by modifying the normals without displacing surfaces. Although there seems to be many bumps in the surfaces, it is no more than a camouflage.
[0005] As shown in FIG. 1( a ), there are parallel, upward normals on a smooth surface. In contrast, a rough surface features disorderly directions of surface normals in FIG. 1( b ). After bump mapping is applied, a smooth surface whose normal directions should be parallel mimics a rough surface with disorderly surface normals as shown in FIG. 1( c ).
[0006] In contrast with bump mapping modifying surface normals only, displacement mapping actually varies surfaces; for example, a screw is created from a cylinder.
[0007] However, the main problem of bump mapping is that real concaves or convexes does not exist in a model. Thus, silhouette edges that seem to pass through a concave does not produce an expected cross section. In other words, silhouette edges still comply with the original geometry of the module. Silhouette appearance seems like flat, even if the bump mapping technique has been applied to emulate a rugged surface.
SUMMARY OF THE INVENTION
[0008] In view of the above-mentioned problems, it is therefore an important object of the invention to provide a method and system of improving silhouette appearance in bump mapping so that the appearance of the bumpy object silhouette approaches the true geometry.
[0009] A method of improving silhouette appearance in bump mapping comprises the following steps: receiving, checking vertex, checking subdivision, subdividing, repeating, displacing and bump mapping. In the receiving step, a triangle of a plurality of triangles is received. In the checking vertex step, whether there is a vertex near silhouette in the triangle is checked. In the checking subdivision step whether the triangle meets a predetermined criterion of subdivision is checked, if the result of the checking vertex step is “YES”. In the subdividing step, the triangle is subdivided if the result of the checking subdivision step is “YES”. In the repeating step, the receiving step the checking vertex step, the checking subdivision step and the subdividing step are repeated until the triangle does not meet the predetermined criterion. In the displacing step, the vertex positions near silhouette along their normals are displaced according to the displacements obtained from displacement mapping if the result of the checking subdivision step is “NO”. Finally, in a bump mapping step, the bump mapping technique is implemented if the result of the checking vertex step is “NO”.
[0010] A system of improving silhouette appearance in bump mapping comprises the following devices. A receiving device receives a triangle of a plurality of triangles. A checking vertex device checks whether there is a vertex near silhouette in the triangle. A checking subdivision device checks whether the triangle meets a predetermined criterion of subdivision if there is a vertex near silhouette in the triangle. A subdividing device subdivides the triangle. A repeating device conducts the receiving device, the checking vertex device, the checking subdivision device and the subdividing device to repeat their own operations until the triangle does not meet the predetermined criterion, and then inputs the triangle into the displacing device. A displacing device of displacing the vertex positions near silhouette along their normals according to the displacements obtained from displacement mapping. And a bump mapping device implements bump mapping if there is no vertex near silhouette in the triangle or after the triangle has been processed by the displacing device.
[0011] In addition, there is provided a machine-readable record medium storing programs for instructing an MPU (Microprocessor Unit) etc. to execute the aforementioned method of improving silhouette appearance in bump mapping.
[0012] Furthermore, there is provided a system of improving silhouette appearance in bump mapping, comprising a CPU and a memory storing instructions so that the CPU can access instructions stored in the memory and execute the aforementioned method of improving silhouette appearance in bump mapping.
[0013] Both bump mapping and displacement mapping can mimic a rugged surface. However, if the surface is not perpendicular to the line of sight, bump mapping has fine visual quality and less mathematic operations, but can not display the closely true geometry of bumps near silhouette. Although the visual quality is quite satisfactory, displacement mapping is limited to use considerable quantity of triangles to mimic the true geometry after the base model has been moved. Thus, in order to combine the advantages of bump mapping and displacement mapping, the invention disclose a method and system: Apply bump mapping to a triangle (surface) near silhouette, or apply displacement mapping to a triangle (surface) not near silhouette. Therefore, the invention not only reduces the operation overhead of applying bump mapping to a whole model, but also retains the true geometry in displaying object silhouette.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] [0014]FIG. 1( a ) is a schematic diagram showing normals of a smooth surface; FIG. 1( b ) is a schematic diagram showing normals of a rugged surface; and FIG. 1( c ) is a schematic diagram showing normals after applying bump mapping.
[0015] [0015]FIG. 2 is a flow chart showing the method of improving silhouette appearance in bump mapping of the invention.
[0016] [0016]FIG. 3 is a schematic diagram showing the near silhouette criterion.
[0017] [0017]FIG. 4 shows that the vertex normal of a vertex is an average of surface normals of all surfaces adjacent to the vertex.
[0018] [0018]FIG. 5 is a schematic diagram that shows how to divide a triangle in the invention.
[0019] [0019]FIG. 6 is a schematic diagram that shows how to divide a triangle having two vertexes near silhouette.
[0020] [0020]FIG. 7 is a schematic diagram that applies displacement mapping.
[0021] [0021]FIG. 8 is an architectural diagram showing the system of improving silhouette appearance in bump mapping.
[0022] [0022]FIG. 9 is also another architectural diagram showing the system of improving silhouette appearance in bump mapping.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] The method of improving silhouette appearance in bump mapping in accordance with the preferred embodiments of the invention will be described with reference to FIG. 2.
[0024] First, in step 21 , a triangle of a plurality of triangles is received.
[0025] Then, in step 22 , if there is a vertex near silhouette in the triangle is checked. If the result of this step is “YES”, step 23 is performed. If “NO”, step 26 is performed.
[0026] Referring to FIG. 3, how to check the vertex in step 22 is set forth as follows:
[0027] Assume that there are a vertex normal {right arrow over (N)}, a view vector {right arrow over (V)} and a known positive real number d, 0≦d≦1,
[0028] if 0≦|{right arrow over (N)}{right arrow over (V)}|≦d, it is called that the vertex is near silhouette,
[0029] wherein {right arrow over (N)} is derived from averaging all surface normals of all triangles adjacent to the vertex, i.e. {right arrow over (N)}=({right arrow over (N)} 1 +{right arrow over (N)} 2 + . . . +{right arrow over (N)} n )/n (In FIG. 4, n=6, for example). The vector from vertex P to eye position E is denoted as {right arrow over (V)}, i.e. {right arrow over (V)}={right arrow over (E)}−{right arrow over (P)}. Note that {right arrow over (N)} and {right arrow over (V)} have to be normalized respectively before the dot product is operated. And, the positive real number d is a user-defined constant.
[0030] The value of {right arrow over (N)}{right arrow over (V)} implies the angle formed between {right arrow over (N)} and {right arrow over (V)}. For example, if {right arrow over (N)}{right arrow over (V)} is equal to 0, it means that they are perpendicular to each other; if {right arrow over (N)}{right arrow over (V)} is equal to 1, it means that they are parallel to each other. Therefore, the positive number d defines a threshold value, which is the user-defined near silhouette criterion.
[0031] In step 23 , whether it is necessary to stop subdividing the first triangle is determined. If the result of this step is “YES”, step 25 is performed; if “NOT”, step 24 is performed.
[0032] In step 23 , according to the predetermined number of subdivision (for example at most 3 times) or minimum dividable area, whether it is necessary to stop subdividing the first triangle is determined. Alternatively, there is another method that the number of subdivision is derived from the distance between an object and the screen. Accordingly, the further the triangle away from the screen, the less subdivision is derived. In contrast, the nearer the triangle close to the screen, the more subdivision is derived. However, no matter which method, there must be a maximum number of subdivision, or it will be trapped in endless loops.
[0033] Take the triangle in FIG. 5( a ) as an example. Calculate three new vertex normals at middle points of three sides of the triangle by using interpolation. Then, four sub-triangles shown in FIG. 5( b ) are obtained after interconnecting three middle points. If there is another subdivision applied in the next loop, sixteen sub-triangles are finally presented in FIG. 5( c ). Moreover, as an alternative subdivision method, a triangle is subdivided into 3 sub-triangles by using the center of gravity of the triangle.
[0034] Referring to FIG. 6( a ), the operations performed in step 21 through step 24 are described in the following. In triangle ACF, {overscore (AC)} is a silhouette, but {overscore (AF)} and {overscore (CF)} are not silhouette. Owing to vertexes A and C near silhouette, triangle ACF is divided into triangle ABD, triangle BCE, triangle DBE and triangle DEF. Also, triangles ABD, BCE and DBE are subdivided again because there is at least one vertex near silhouette in each triangle. Similarly, each of the resultant triangles are subdivided once more as shown in FIG. 6( b ).
[0035] In step 25 , vertex positions near silhouette along their normal is displaced. According to the displacements along their vertex normals in displacement mapping, displace vertex positions. An original triangle in FIG. 7( a ) is divided into four sub-triangles in FIG. 7( b ) after the first division by using interpolation. After displacement mapping is applied to each vertex, the displacement of each vertex of the triangles is illustrated in FIG. 7( c ). Through interpolation, 16 sub-triangles in FIG. 7( d ) are obtained after the second subdivision. Similarly, after displacement mapping is applied to each vertex, the displacement of each vertex of the triangles is illustrated in FIG. 7( e ).
[0036] Finally, in step 26 , the bump mapping technique is implemented.
[0037] Besides, referring to FIG. 8, in this embodiment, a system of improving silhouette appearance in bump mapping comprises seven parts: a receiving device 81 , a checking vertex device 82 , a checking subdivision device 83 , a subdividing device 84 , a repeating device 85 , a displacing device 86 and a bump mapping device 87 . The aforementioned seven parts will be described hereafter.
[0038] Receiving device 81 receives a first triangle of a plurality of triangles. Checking vertex device 82 checks whether there is a vertex near silhouette in the first triangle. Checking subdivision device 83 checks whether the first triangle meets a predetermined criterion of subdivision, if there is a vertex near silhouette in the first triangle. Subdividing device 84 subdivides the first triangle. Repeating device 85 directs the receiving, the checking vertex, the checking subdivision and the subdividing devices to repeat their own operations until the first triangle does not meet the predetermined criterion, then inputs the first triangle into the displacing device. Displacing device 86 displaces the vertex positions near silhouette along their normals according to the displacements obtained from displacement mapping. Bump mapping device 87 implements bump mapping if there is no vertex near silhouette in the first triangle, or after the first triangle has been processed by the displacing device.
[0039] Further, the system of improving silhouette appearance in bump mapping can also be manufactured into hardware chip modules like ASICs for speeding up image processing by one of ordinary skill.
[0040] Besides, FIG. 9 is another system of improving silhouette appearance in bump mapping, different from the architecture of FIG. 8, includes a CPU 91 and a memory storing instructions 92 . CPU 91 can access instructions stored in the memory and execute a method of improving silhouette appearance in bump mapping as described in FIG. 2.
[0041] Note that CPU 91 can be any architecture, such as ALU (arithmetic logic unit) for mathematic and logic operations, registers for storing data or instructions temporarily and control units for controlling all operations of computers. Memory storing instructions 92 can be any computer-readable memory that can store data, such as dynamic random access memory (DRAM), read only memory (ROM), electrically erasable programmable read-only memory or the combination.
[0042] The above-described embodiment should be considered in all respects as illustrative and not restrictive. Any modifications and changes made to the invention should be included in the appended claims without departing from the spirit and scope of the invention as set forth in the appended claims. | The invention provides a method of improving silhouette appearance in bump mapping, which not only reduces the operation overhead of applying displacement mapping to a whole model but also retains the truly geometric shape in displaying the object silhouette. The invention comprises the following steps: receiving, checking vertex, checking subdivision, subdividing, repeating, displacing and bump mapping. The invention also discloses a system employing the method of improving silhouette appearance in bump mapping. | 6 |
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a device for fastening a clamping bar which is employed for holding and clamping coverings, such as rubber blankets on rubber blanket cylinders of offset printing presses.
The published German Patent Document DE 42 22 332 A1 discloses a device for fastening a rubber blanket on a rubber blanket cylinder of an offset printing press, wherein the ends of the rubber blanket are clamped in clamping bars, which are fastened, in turn, to clamping shafts. The clamping bars, respectively, are formed with a projection wherein a shoulder of the clamping bar is engageably disposed. To prevent the clamping bar from being pivoted outwardly from the clamping shaft about the engagement position, a spring-loaded retaining clip is provided.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a device for fastening a clamping bar so as to lock thereby a covering on a clamping shaft in a manner not heretofore contemplated or suggested by the state of the art.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a device for fastening a clamping bar for clamping a covering to a clamping shaft formed with a groove wherein the clamping bar engages, including a spring-loaded retainer disposed on the clamping shaft and engaging in the clamping bar, the device further comprising a locking element radially displaceable in the clamping shaft.
In accordance with another feature of the invention, the locking element is a spring-loaded bolt.
In accordance with a further feature of the invention, the device includes an actuator for the locking element.
In accordance with an added feature of the invention, the actuator is a leaf spring.
In accordance with an additional feature of the invention, the leaf spring is formed with a loop.
In accordance with yet another feature of the invention, the actuator is disposed in an opening formed in the clamping bar.
In accordance with a concomitant feature of the invention, the covering is a rubber blanket, and the clamping shaft and clamping bar are on a blanket cylinder of an offset printing press.
An advantage of the invention is that the retaining clamps can be provided with a very low spring force, so that a human operator can easily actuate them. At the same time, by providing the locking element according to the invention, the clamping bar is prevented from coming loose form the clamping shaft. This provision avoids any possibility of the clamping bar dropping onto other cylinders, such as printing unit cylinders of a printing press, and causing subsequent damage to those cylinders.
In an advantageous construction, an actuator for unlocking the locking element is provided, which assures relatively easy manipulation.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a device for fastening a clamping bar, 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.
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, in which:
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is an enlarged cross-sectional view of FIG. 2 taken along a line I--I therein, in the direction of the arrows, and rotated 90° clockwise, and showing a rubber blanket cylinder of an offset printing press having the fastening or locking device for a clamping bar according to the invention;
FIG. 2 is a plan view of the clamping bar;
FIG. 3 is an enlarged cross-sectional view of FIG. 2 taken along the line III--III in the direction of the arrows, and rotated clockwise through an angle of 90°; and
FIG. 4 is an enlarged fragmentary, longitudinal sectional view of FIG. 2 taken along the line VI--VI in the direction of the arrows, and showing the clamping bar with an actuating device forming part of the invention of the instant application.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings and, first, particularly to FIGS. 1 and 3 thereof, there is shown therein a rubber blanket cylinder 1 of an offset printing press provided with two clamping shafts 2, respectively, at each of the end faces thereof. By means of a rib or strip 3, an axially parallel gap or trench formed in the rubber blanket cylinder 1 is subdivided into two recesses 6. The clamping shafts 2 are respectively, swivelably disposed in the respective recesses 6. Because the clamping shafts 2 are arranged mirror-symmetrically, the device of the invention will be described hereinafter with respect to only a single clamping shaft 2. The clamping shaft 2 is formed with a flattened surface 7 in an upper region thereof, as viewed in FIGS. 1 and 3. At a region facing towards an open side of the recess 6, the clamping shaft 2 is formed with a projection or protrusion, which extends axially parallel over the length of the clamping shaft 2. With the flattened surface 7, the protrusion or projection 8 forms a groove 9.
One end 11 of a covering 12, such as a rubber blanket, is clamped between two clamping elements 13 and 14 of a clamping bar 16, which rests on the flattened surface 7 of the clamping shaft 2, and is formed with a shoulder 17 with which it engages in the groove 9. To secure the clamping bar 16 against swiveling away from the clamping shaft 2 about a pivot point located on a surface of the projection 8 defining the groove 9, at least one and preferably two spaced-apart retaining clamps 18 are provided. A spring-loaded retainer 18 in the form of a retaining clamp or retaining clip 18 is secured to the clamping shaft 2 at a side thereof opposite the projection 8. At an upwardly directed end thereof, as viewed in FIG. 3, the retaining clip 18 is formed with a hook 19. The retaining clip 18 itself is bent in the form of a loop and has a spring force which presses the hook 19 over a shoulder 21 (note FIG. 2). A recess in the clamping element 14 of the clamping bar 16 forms the shoulder 21.
As shown in FIG. 3, the clamping bar 16 is fixed on the clamping shaft 2 by the engagement of the shoulder 17 in the groove 9 at a front region of the clamping bar 16 located at the right-hand side of the figure and, in a rear region thereof, by the engagement of the hook 19 and the shoulder 21.
A locking device 24 is provided for securing the clamping bar 16 against displacement on the flattened surface 7 of the clamping shaft 2 counter to the spring force of the retaining clip 18. The locking device 24 has a movable spring-loaded bolt 26, which is mounted in a bore 27 at the bottom of the clamping shaft 2, as viewed in FIG. 1. The bore 27 is formed in the clamping shaft 2 approximately midway along the axial length thereof.
The bolt 26 has a longitudinal axis 28 which is perpendicular to a plane coinciding with the flattened surface 7. The bolt 26 is axially displaceably supported in the bore 27. The bore 27 is a through bore, which has a larger diameter in a lower region thereof remote from the flattened surface 7 than in an upper region thereof, as viewed in FIG. 1. A shoulder 29 located between the upper and the lower regions of the bore 27 acts as a stop for the bolt 26, with which the bolt 26 is engageable by means of a collar 31. A screw 32, which closes off the through bore 27 in a lower region thereof, serves as an abutment or counterbearing for a spring 33, which is braced, at one end thereof, against the screw 32 and, at the other end thereof, against the bolt 26. To achieve stable guidance for the spring 33, the bolt 26 is formed with a bore 34 which extends in the direction of the axis 28, and into which the spring 33 projects. The head 36 of the bolt 26 protrudes beyond the plane of the the flattened surface 7, and one side thereof rests against a side wall defining a recess 37 which is formed in the clamping element 14 of the clamping bar 16.
A resilient actuator in the form of a leaf spring 41 is held by means of a fastener 39 in a further recess 38 formed in the clamping element 14, as shown in FIG. 4. The recess 38 extends in the direction of the clamping bar 16 and intersects the recess 37 in the vicinity of the bolt 26. On an end of the actuator 41 distal from the fastening location thereof, the actuator 41 has an operator element, preferably in the form of a loop 42, at the end of the leaf spring 41. The operator element 42 is disposed above the head 36 of the bolt 26 and is bringable into operative contact therewith counter to the force of the leaf spring 41. The operator element 42 is disposed in openings 44 and 46 formed in the clamping elements 13 and 14, respectively, of the clamping bar 16 and protrudes upwardly out of the clamping bar 16, as viewed in FIG. 4, for such a distance that it is able to be actuated manually, for example.
To secure the clamping bar 16 to the clamping shaft 2, the clamping bar 16 is placed with the underside thereof on the head 36 of the bolt 26, and the latter is pressed counter to the force of the spring 33 so far downwardly into the bore 27 that the clamping bar 16 rests on the flattened surface 7 of the clamping shaft 2. Due to the spring force of the retaining clip 18, the hook 19 is pressed over the shoulder 21 and secures the clamping bar 16 against being lifted from the clamping shaft 2. Then, the clamping bar 16 is displaced so far towards the opening of the recess 6 that the shoulder 17 engages in the groove 9. When the shoulder 17 is correctly engaged in the groove 9, the bolt 26 is automatically thrust upwardly by the force of the spring 33 into the recess 37 until it rests against the side wall defining the recess 37. The clamping bar 16 is thereby secured against displacement.
To release the clamping bar 16 from the clamping shaft 2, the operator element 42 is pressed downwardly towards the clamping shaft 2, as viewed in FIG. 4, counter to the force of the leaf spring 41 and the force of the spring 33, until the bolt 26 has plunged through the periphery of the clamping shaft 2. The clamping bar 16 on the flattened surface 7 can then be displaced so far counter to the force of the retaining clip 18, that the shoulder 19 of the clamping bar 16 disengages from within the groove 21. The clamping bar 16 can then be removed from the clamping shaft 2. | Device for fastening a clamping bar for clamping a covering to a clamping shaft formed with a groove wherein the clamping bar engages, including a spring-loaded retainer disposed on the clamping shaft and engaging in the clamping bar, the device further including a locking element radially displaceable in the clamping shaft. | 1 |
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0001] This application is a Continuation of U.S. application Ser. No. 10/556,935, filed Nov. 16, 2005, which is the National Stage of International Application No. PCT/EP2004/005229, filed May 14, 2004, which is based upon and claims the benefit of priority from prior German Patent Application No. 103 22 457.2, filed May 16, 2003, the entire contents of all of which are incorporated herein by reference in their entirety.
BACKGROUND
[0002] The invention relates to an air distributor device, in particular for air distribution in a ventilation system of a motor vehicle, or to an air mixing device, in particular for regulating the temperature in an air conditioning apparatus of a motor vehicle, according to the preamble of claim 1 .
[0003] Devices of this type are used for two different applications, that have many features in common. On the one hand, the air distributor device serves as a kind of switch, an air distributor flap dividing inflowing air into two or more airstreams or bunching a plurality of part streams. Switches of this type are used, for example, in the fresh-air/circulation-air housing of a ventilation device of a motor vehicle. On the other hand, air distributor devices of this type may serve for regulating the temperature in an air conditioning apparatus. In this case, a cold-air flap and a warm-air flap, with the aid of which the temperature is regulated, are provided in the air guide housing, in the “maximum heating” state the warm-air flap being opened completely and the cold-air flap closed completely, in the “maximum cooling” state the warm-air flap being closed completely and the cold-air flap opened completely, and, in a regulated state, the two flaps being opened partially.
[0004] Thus, the air distributor device known from FR 2 763 286 A1 has a housing with two air inlets arranged at an angle to one another. A moveable flap has a sealing-off wall and two actuating elements, by means of which the flap can be moved into two positions in which it seals off the air inlets. The flap is connected to the housing by means of guides which have the effect that the flap moves in a movement which differs from straightforward rotation. The guides have two curved tracks and two pins which are provided on the flap and are spaced apart from one another and which are guided in the curved tracks.
[0005] The known air distributor devices have the disadvantage that at least two flaps are required for each zone of an air conditioning system. In addition, there is the kinematic or electrical coupling, for example via a stepping motor or a U-type socket, such coupling, together with the necessary pivoting travel of the flaps, not allowing a compact type of construction.
SUMMARY OF PREFERRED EMBODIMENTS
[0006] The object of the invention is to make available an improved air distributor device or air mixing device.
[0007] This object is achieved by means of an air distributor device or an air mixing device having the features of claim 1 . Advantageous refinements are the subject matter of the subclaims.
[0008] According to the invention, an air distributor device or an air mixing device is designed in such a way that the air guide housing has provided in it one air inlet and two air outlets or two air inlets and one air outlet which can be closed completely and/or partially by means of the flap. In this case, the two air outlets or air inlets are arranged preferably essentially parallel to one another.
[0009] Since in each case one flap is dispensed with, as compared with the prior art, a more compact type of construction is possible. Furthermore, there is no need for mechanical coupling, for example via an actuating lever, with the result that construction space is saved and the hysteresis is reduced. Moreover, the use of a sliding flap affords acoustic benefits.
[0010] According to one embodiment, for guiding the flap, two curved tracks arranged one above the other and two pins attached to the flap and aligned with one another are provided. In this case, the curved track is preferably designed to be straight, with essentially straight portions and/or in one radius, although other curved track forms are also possible. Other guides are likewise possible. According to an alternative embodiment, a control peg or a control yoke is provided for guiding the flap.
[0011] Preferably, a carrier module is provided, which is inserted into the air guide housing and surrounds the flap together with the guide of the latter. This allows simple preassembly and simplifies final assembly.
[0012] The flap may preferably be positioned via an actuating lever, in particular into at least two positions, preferably into any desired positions between two end positions. The actuating lever is preferably connected pivotably to a driveshaft and to the flap, so that only pull and/or push forces take effect.
[0013] An air spoiler which positively influences the airflow may be provided at or in the region of the actuating lever.
[0014] A sealing edge ensures, particularly in the case of air mixing devices, that there is a separation of cold and warm air.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The invention is explained in detail below by means of an exemplary embodiment having variants, with reference to the drawing in which:
[0016] FIGS. 1 a and 1 b show two sectional illustrations of an air distributor device in various positions, the heating position being illustrated on the left and the cooling position on the right in FIG. 1 a, and an intermediate position being illustrated on the left and the cooling position on the right in FIG. 1 b,
[0017] FIGS. 1 c and 1 d show two sectional illustrations of the air distributor device of FIGS. 1 a and 1 b with an illustration of the airflow,
[0018] FIG. 1 e shows a sectional illustration of a detail of the air distributor device of FIG. 1 d with an illustration of the airflow,
[0019] FIG. 2 a - c show a perspective illustration of a first variant of the exemplary embodiment in various positions, the heating position being illustrated in FIG. 2 a, an intermediate position in FIG. 2 b and the cooling position in FIG. 2 c,
[0020] FIG. 3 a - d show various illustrations of a second variant of the exemplary embodiment,
[0021] FIG. 4 a - c show various variants of the lever articulation, and
[0022] FIG. 5 a - e show various curved tracks.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] An air distributor device 1 according to the invention with an air guide housing 2 , which is designed in the manner of a switch with one air inlet 3 and with two air outlets 4 , 5 , has a displaceable flap 6 which, as required, can close the air outlets 4 and 5 . In this case, cold air coming from an evaporator is supplied through the common air inlet 3 and, on its way through the air outlet 5 , is conducted through a heating body and warmed by the latter. On the way through the air outlet 4 , the heating body is bypassed, and therefore no warming of the air takes place. In the present instance, two air distributor devices 1 arranged axially symmetrically are arranged, the two air outlets 5 being located centrally.
[0024] Only one of the two air guide devices 1 is described in more detail below. The flap 6 , on one side, has two pins 7 which are aligned with one another and are guided in curved tracks 8 formed parallel to one another in the air guide housing 2 and, on its other side, has a pivotably attached actuating lever 9 which, for example, displaces the flap 6 by means of a servomotor (not illustrated).
[0025] FIG. 1 a, left half, shows a first end position of the flap 6 , in which the flap 6 closes the air outlet 4 completely and releases the air outlet 5 completely. When the flap 6 is actuated by means of the servomotor, the actuating lever 9 executes essentially a pivoting movement, at the same time taking up that end of the flap 6 which is connected to it, whereas that region of the flap 6 which is located in the vicinity of the pins 7 follows essentially the path of the curved tracks 8 . In the intermediate position illustrated on the left in FIG. 1 b, both air outlets 4 and 5 are partially released, while, in the second end position illustrated on the right in FIGS. 1 a and b, the air outlet 4 is completely open and the air outlet 5 is completely closed. FIG. 1 e shows the overflow of the air downstream of the flap 6 , with the result that the air flow or the air mixture can be influenced positively. If the overflow is not desired, it can be prevented by means of the movement geometry of the flap 6 , for example by the flap 6 coming to bear in the region of the overflow during the movement cycle. A sealing edge in this region can improve this effect.
[0026] FIG. 2 a - c show a first variant with straight curved tracks and in which the flap 6 executes a straightforward longitudinal movement. Identical or identically acting components are designated by the same reference symbols as in the exemplary embodiment described above, without these being described in any more detail. The sliding flap 6 may be controlled, during movement, as a function of the shape of the guide track, in such a way that the flap 6 bears against the sealing frame in the two end positions, but runs freely in the intermediate positions.
[0027] According to a variant illustrated in FIG. 3 a - d, guidance takes place via a control peg 9 ′, in which case the pins and curved tracks may be dispensed with.
[0028] FIG. 4 a - c show different variants of the lever articulation of the actuating lever or actuating levers 9 . In this case, two actuating levers 9 are in each case connected at their “free” ends pivotably to the flap 6 and at their other ends, for reasons of stability, to a driveshaft 10 , one actuating lever 9 being articulated in the upper region of the flap 6 and one actuating lever 9 being articulated in the lower region of the latter. According to a variant illustrated in FIG. 4 a, a guide spoiler 11 for air guidance is provided, which runs over about half the flap height. In the second variant illustrated in FIG. 4 b, there is no guide spoiler provided. The third variant illustrated in FIG. 4 c has an L-shaped guide spoiler 11 , one leg of which runs between the driveshaft 10 and flap 6 and the other leg of which runs near the flap 6 parallel to the driveshaft 10 toward the lower actuating lever 9 . The air spoiler 11 has an effect on the air mixture. The air spoiler 11 may also have other forms of construction, for example three-dimensional shapes, for defined air guidance.
[0029] FIGS. 5 a - e show various variants of curved tracks along which the pins can be guided. Normally, guidance takes place via two pairs of aligned pins, although, for example, only one pair of aligned pins and a single pin arranged on the opposite side may also be arranged. Further pin arrangements are possible. If the curved tracks are designed in such a way that the flap does not rub, that is to say, during adjustment, it is first moved away from its bearing surfaces, then a reduced effort is required for adjustment and the useful life of seals is increased.
[0030] The figures do not illustrate any sealing edges which may be located on the flap and/or on the carrier module.
[0031] By a reversal of direction, that is to say a reversed airflow direction, the air distributor devices described above become air mixing devices.
LIST OF REFERENCE SYMBOLS
[0000]
1 Air distributor device
2 Air guide housing
3 Air inlet
4 , 5 Air outlets
6 Flap
7 Pins
8 Curved track
9 Actuating lever
9 ′ Control peg
10 Driveshaft
11 Guide spoiler | The invention relates to an air distributor device ( 1 ) comprising an air conduction housing ( 2 ) and a displaceable flap ( 6 ) that is located in the air conduction housing ( 2 ). Said air conduction housing is equipped with an air inlet ( 3 ) and at least two air outlets ( 4, 5 ), which can be completely and/or partially sealed by the flap ( 6 ). The invention also relates to an air mixing device that is configured in a corresponding manner. | 1 |
This is a Division of application Ser. No. 07/553,872, filed Jul. 16, 1990, now U.S. Pat. No. 5,131,218.
FIELD OF THE INVENTION
The present invention relates to ropes, and more particularly, to a novel floating/sinking rope formed of non-corrosive/non-toxic materials having enhanced abrasion and UV resistance and in which the strands of the floating and sinking portions of the rope are joined in a unique way to enhance the breaking strength of the rope over its entire length and especially in the region where the floating and sinking portions are joined.
BACKGROUND OF THE INVENTION
Historically, crab and lobster fishermen have used two ropes joined together by a knot and attached one end to a float and the other end to a trap or "pot" employed for deep water fishing.
A normal rigging employs a sinking line having a specific gravity greater than one, i.e. a specific gravity greater than that of water, which extends from the float and having a length typically on the order of twenty-two (22) fathoms. The sinking line prevents the rope from floating upon the surface, thereby creating a potential hazard. At this point, the sinking line is joined, i.e. knotted to, a floating line having a specific gravity less than one with the length of the floating line being determined by the depth of the water. The floating line is then joined to the "pot". This design is extremely advantageous for use in such deep sea fishing since fishermen desire that the line attached to the "pot" should not scare the catch. This objective is accomplished by the floating rope section which floats above the "pot".
Joining the floating and sinking rope sections with a knot is disadvantageous since a knot of any type reduces the strength of a line by 50 percent. The knowledge of this degradation in strength has lead to the development of a partially leaded polypropylene line having a lead wire incorporated into a portion of the rope, said lead wire extending over a length of the order of twenty-two fathoms. A sufficient amount of lead is used to overcome the specific gravity of polypropylene which is less than that of water. In producing the rope, when the length of twenty-two fathoms is reached, the lead wire is terminated and the remainder of the rope length is formed by continuing the polypropylene portion of the rope which, having a specific gravity less than water (i.e., less than 1.0), floats.
Although the last-mentioned design provides a floating/sinking rope yielding the desired objectives of the fishermen, there are nevertheless some important deficiencies which include the following:
1. In cold water the ductility of the lead is significantly reduced and the lead becomes brittle. Due to the natural elongation of the polypropylene line when in use (the elongation is commonly of the order of 15 percent) the lead breaks, and, through continued use, the lead works its way out of the line thereby decreasing its sinkability.
2. The lead lost into the sea becomes an environmental threat, due to its toxicity (i.e., lead is poisonous).
3. The polypropylene line softens due to the voids caused by the lead which has worked its way out of the polypropylene line causing the line to wear more quickly thus significantly reducing its operating life.
4. The lay of the entire line changes as the rope, when floating freely, works itself toward a neutral lay or degree of twist.
It is, therefore, extremely advantageous to provide a rope having all the characteristics of the floating/sinking ropes of the prior art which overcome the disadvantages of lead filled rope and rope whose floating and sinking portions are knotted together.
BRIEF DESCRIPTION OF THE INVENTION
The present invention is characterized by comprising a floating/sinking rope which is formed of materials which are non-metallic and hence non-corrosive and, more particularly, which are non-toxic. The rope is formed of synthetic materials and, more particularly, synthetic plastic materials of first and second types having specific gravities respectively greater than and less than 1.0 (1.0 being the specific gravity of water). The materials preferably have contrasting colors to differentiate the floating and sinking rope portions by a simple visual observation.
The sinking portion of the floating/sinking rope is preferably formed first and is comprised of strands, each having a plurality of blended yarns formed of a combination of the materials of said first and second specific gravities whose proportions are selected to yield yarns having a resultant specific gravity greater than one.
The blended yarns are arranged so that the filaments having a specific gravity greater than one and which are also resistant to ultraviolet radiation and have a superior abrasion resistance, are arranged to form a cover layer surrounding the filaments having a specific gravity less than one.
Rope strands are formed by combining a predetermined number of the blended yarns, all of substantially the same diameter. When the strand being formed reaches a predetermined length, selected yarns of said strand are terminated in a staggered fashion along the length of the strand and each terminated yarn is replaced with a yarn formed only of fibers having a specific gravity less than one to thereby form the floating rope section. The yarns of the sinking rope section which are not terminated are continued over the entire length of the floating section. By terminating the selected yarns of the sinking rope section in a staggered fashion and hence initiating the replacement yarns for the floating rope section in a complementary staggered fashion and by forming the blended and unblended yarns of substantially equal diameters, the yarns which are twisted to form each strand have a breaking strength in the transition region between the sinking and floating rope portions which is equal to the breaking strength of the sinking and floating rope portions themselves.
The fibers having a specific gravity greater than one are formed of a material having a high abrasion resistance and also having a high resistance to ultraviolet radiation. The fibers having a specific gravity of less than one are also highly sensitive to ultraviolet radiation. These last-mentioned fibers are surrounded by the fibers having a specific gravity greater than one, whereby the overall abrasion resistance of the rope and the overall resistance to UV radiation are greatly enhanced.
Once strands having sinking and floating portions of the desired length are formed, a plurality of such strands (typically three) are joined together, i.e. either twisted or braided, to form the floating/sinking rope. The elimination of knots and/or lead employed in prior art designs eliminates all of the disadvantages of floating/sinking rope of the lead filled type and the method of joining said sections provides a rope which has no reduced strength sections, especially in the transition region between the floating and sinking portions.
OBJECTS OF THE INVENTION
It is, therefore, one object of the present invention to provide a novel method for producing floating/sinking rope which totally avoids and eliminates metallic, corrosive and toxic elements typically utilized to form the sinking portion thereof.
Still another object of the present invention is to provide a novel method for producing a floating/sinking rope having a sinking portion of enhanced flexibility as compared with conventional sinking rope portions.
Still another object of the present invention is to provide a novel method for producing a floating/sinking rope having floating and sinking rope portions which are joined in a unique manner and which eliminates the need for knotting said sections together as well as eliminating the disadvantages which result from a knotted rope.
Still another object of the present invention is to provide a novel method for producing a floating/sinking rope having a substantially uniform diameter over the entire length thereof.
Another object of the present invention is to provide a novel floating/sinking rope formed of synthetic materials having enhanced abrasion resistance and resistance to ultraviolet radiation as compared with conventional rope.
Still another object of the present invention is to provide a novel floating/sinking rope formed of synthetic materials of different specific gravities arranged in a fashion to form floating and sinking rope portions joined in a transition section in a manner such that the breaking strength of the transition section is substantially equivalent to the breaking strength of the floating and sinking portions.
BRIEF DESCRIPTION OF THE FIGURES
The above, as well as other objects of the present invention will become apparent when reading the accompanying description and drawings in which:
FIG. 1 shows a simplified diagrammatic view comparing the rope of the present invention with conventional rope when in use;
FIG. 2a shows, a sectional view of one strand of a sinking section of rope designed in accordance with the principles of the present invention;
FIG. 2b is a sectional view showing a sinking section of a three strand rope, each strand embodying the design shown in FIG. 2a;
FIG. 3a is a sectional view showing one strand of a floating section of the rope embodying the principles of the present invention;
FIG. 3b shows a sectional view of the sinking section of a three strand rope embodying the strand arrangement shown in FIG. 3a;
FIG. 4 shows a schematic diagram of a system for forming strands in accordance with the principles of the present invention;
FIG. 4a is a front view of the reeve plate shown in FIG. 4;
FIG. 5a is a perspective view of apparatus for forming a floating/sinking rope;
FIG. 5b is a perspective showing of a detailed view of a portion of the apparatus for forming yarns in accordance with the principles of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a comparison of a fishing rope 10 of the prior art compared with a fishing rope 20 embodying the principles of the present invention.
Fishermen seeking deep sea catch such as crab and lobster, for example, have traditionally employed a rope 10 shown in FIG. 1 which is comprised of two rope portions, namely a sinking line portion 12 and a floating line portion 14 joined together by a knot 16. The sinking line 12, having a specific gravity greater than one is coupled at its upper end to float 17 and is coupled at its lower end to the upper end of floating line 14 by knot 16. The floating line, which has a specific gravity of less than one, has an overall length typically determined by the depth of the water. In the example shown in FIG. 1, the floating line has a length of forty-four fathoms. The lower end of floating line 14 is coupled to the "pot" 18. A knot of any type is known to reduce the strength of the rope by 50 percent, thereby yielding a rope 10 which is of inferior quality.
Rope 20 of the present invention has a sinking line portion 22 whose upper end is coupled to float 17 and a floating line portion 24 whose lower end is coupled to "pot" 18. Contrary to the design of rope 10, the rope 20 of the present invention has no knots, and makes a smooth transition from the sinking line portion 22 to the floating line portion 24 thereby significantly enhancing the overall strength of the line. As will be more fully described hereinbelow, the novel rope 20 of the present invention eliminates the need for metallic elements within the rope thus eliminating possible corrosion and also yields a non-toxic rope which does not contaminate or pollute the water and the inhabitants thereof.
As was pointed out hereinabove, one rope design which eliminates the need for knotting sinking and floating lines together utilizes a lead wire within the sinking rope portion. The amount of lead employed is a function of the rope material whose specific gravity is less than one. The lead wire is simply terminated at the lower end of the sinking rope portion when making the rope and the remainder of the rope, i.e. the floating line portion, is produced with the lead wire omitted. The material of the floating line portion obviously has a specific gravity of less than one in order to achieve the desired results.
The disadvantages of a lead-filled rope have been pointed out hereinabove and the lead-filled rope and knotted rope 10 shown in FIG. 1 clearly establish the need for a rope having the advantageous features of the present invention and, more specifically, which eliminates the disadvantageous features of lead-filled and knotted ropes of the sinking/floating type.
The present invention is characterized by comprising a sinking rope portion which is preferably produced first and which is comprised of a plurality of strands, each strand being substantially of the same common diameter and being formed of a plurality of blended yarns formed of first and second type material which are blended in accordance with a proportionality which yields strands having a specific gravity greater than one. FIG. 2a shows a typical strand S employed to make the sinking rope section. Strand S is comprised of a plurality of individual yarns Y each having the same common diameter. Each of the yarns Y is formed of first and second fibers wherein one of said fibers has a specific gravity which is less than one while the other fiber has a specific gravity of greater than one. These fibers are blended in such a manner as to form a yarn Y which has a resultant specific gravity of greater than one. Yarns Y will hereinafter be referred to as "blended yarns". In one preferred embodiment, the strand of the sinking rope section is formed of a polyester fiber "veneered" over a polyolefin fiber to produce a blended yarn that contains sufficient polyester, having a specific gravity of 1.38, to more than counterbalance the buoyant effect of the polyolefin which has a specific gravity of 0.91. The desired ratio of polyester to polyolefin is 51:49 in the preferred embodiment of the present invention. Thus, as shown in FIG. 2a, the polyolefin fibers form the core C of each yarn while the polyester fiber forms the outer layer L which completely surrounds the core C of each yarn Y.
The polyolefin fibers are sensitive to ultraviolet radiation. By covering the polyolefin fibers 100 percent with the polyester fibers, which are 100 percent ultraviolet resistant, the polyolefin fibers are protected from degradation due to ultraviolet radiation. In addition, the polyester fibers are also more resistant to abrasion than the polyolefin fibers thereby reducing abrasion between and among neighboring yarns within each strand, as well as between yarns of the adjacent strands forming the rope.
The polyolefin fibers may also contain a hindered amine light stabilizer (HALS) that resists ultraviolet degradation. The amount of stabilizer introduced guarantees minimal strength loss when tested at the approximate latitude of 30 degrees for one year of outdoor exposure.
Each of the blended yarns Y are of a common uniform diameter, as shown.
The method of manufacture of the sinking section, the strands of which are produced first, is the production of the blended yarns to insure sinkability. When the normal twenty-two fathom length is reached, a sufficient number of the blended yarns in the sinking section (normally five to six) are exchanged for 100 percent polyolefin yarns. More specifically, the blended yarns Y are removed and are replaced by polyolefin yarns Y p as shown in FIG. 3a. Polyolefin yarns are formed of polyolefin fibers wherein each yarn Y p has a diameter substantially the same as the diameter of the blended yarns Y. The polyolefin yarns which, as was described hereinabove, have a specific gravity of 0.91, together with the ratio of the blended to the polyolefin yarns within the floating strand S F , is sufficient to form a strand S F which floats. The ratio of polyester to polyolefin is changed from the sinking rope section which is 51:49 to the desired 30 percent polyester, 70 percent polyolefin. The yarn exchange preferably takes place over a three to four fathom length in order to maintain the diameter of the rope uniform and in order to maintain its strength and integrity.
The manner of forming the blended yarn will now be described in greater detail in connection with FIG. 4 which shows a blended yarn veneering reeve plate E (FIG. 4a) having a central opening E1 for receiving a yarn comprised of polyolefin fibers and openings E2 about its circumferential portion each for receiving yarns B comprised of polyester fibers.
The polyolefin yarn A is derived from a source O and passes through the central opening E1 in reeve plate E (see FIG. 4a). A plurality of tubes B containing polyester yarn are arranged at spaced intervals about an imaginary circle and each tube feeds a polyester yarn through an associated one of the openings E2 in reeve plate E arranged about the circumference of the plate. FIG. 4 shows only two such yarns and bobbins for purposes of simplicity.
All of the yarns passing through the reeve plate are drawn together to form a blended yarn G comprised of twisted polyolefin yarns and polyester yarns. The polyolefin yarn A from the extrusion line is maintained at a higher tension in moving toward the yarn twister, located at G, as compared with the tensions of the polyester yarns. Tension wheels F are operated to provide the desired tension. The tension differential causes the polyester yarns to wrap around the polyolefin yarn. The number of yarns of polyester B employed in forming a blended yarn and the line speed of the yarn twister determine the effectiveness of the cover. The twister, although not shown, may be any conventional twister capable of providing the desired twist. For example, note the twister 55 described in U.S. Pat. No. 3,201,930 and further disclosed in FIGS. 5 and 6 of said patent. Alternatively, any other suitable twister may be employed. The individual polyester and polyolefin yarns are preferably twisted preparatory to formation of the blended yarn shown in FIG. 4. The number of polyester yarns employed and the line speed of the yarn twister determine the effectiveness of the cover. So long as the relative tensions between the polyester and polyolefin yarns are different and so long as the tension on the polyolefin yarn is greater than the tension on the polyester yarns, the yarns with least tension will wrap around the higher tension yarn.
The number of fibers in the blended yarn is chosen to yield a composite blended yarn having a specific gravity greater than one. In the preferred embodiment, when employing polyester and polyolefin fibers, the ratio of polyester to polyolefin is 51 percent to 49 percent (i.e. 51:49). Given the specific gravities of these two materials, the resulting specific gravity of the blended yarn is greater than one.
In order to form a floating/sinking rope, the blended yarns are formed in the manner described in connection with FIG. 4 and the 100 percent polyolefin yarns are formed in any suitable fashion.
A strand of all blended yarns is formed utilizing the apparatus shown in FIGS. 5a and 5b. The rope strand is started with all yarns being the blended yarns (see FIG. 2a) having a specific gravity greater than one. FIG. 5b shows a strand creel 30 provided with a plurality of yarn bobbins 32 of the aforementioned blended yarns shown, for example, in FIG. 2a. The blended yarns are drawn through a strand die 34 and are ultimately twisted into a strand, for example, of the type described hereinabove. When a predetermined length of sinking rope is formed, selected ones of the blended yarns are exchanged by terminating selected ones of the blended yarns and switching them with 100% polyolefin yarns. This is accomplished by removing one of the packages of blended yarn from the strand creel 30 and replacing this package with a 100 percent polyolefin yarn package. The polyolefin yarn leader 36 is inserted into the center of the strand at the strand die 34 utilizing a strand insertion tool 38 shown in FIG. 5a. The leader end of the 100 percent polyolefin yarn is looped through the eye 38a of insertion tool 38. The tool 38 is pulled through the strand being formed within the tubular member 40. By looping the new yarn through the eye 38a of tool 38 and pulling the tool through the strand, the new yarn is introduced into the strand without a knot. This method insures both a substantially constant diameter and constant strength for the strand and thereby provides a rope of constant strength.
All of the blended yarns chosen to be replaced with the 100 percent polyolefin yarn are exchanged in a staggered fashion, preferably over a twenty foot length of strand to maintain rope strength and diameter uniform throughout the transition region between the floating and sinking portions. The transition section thus gradually moves from negative buoyancy to positive with no discernible change in its diameter. This is accomplished by employment of the staggered method and further by forming the blended yarns and the 100 percent polyolefin yarns of substantially the same diameter and twisting the yarns forming the strand.
In one preferred embodiment, the floating and sinking rope sections are made easily distinguishable to the eye by utilizing polyolefin yarns of a first color which replace the white blended yarns employed in the sinking portion of the rope thus aiding in a simple differentiation of the sinking and floating rope portions.
When the proper number of blended yarns have been replaced by 100 percent polyolefin yarns, the ratio of blended to polyolefin yarns is maintained throughout the remaining length of the rope. Typically, a floating/sinking rope has a sinking rope section of twenty-two fathom length and a floating rope section of the order of forty-four fathom length for a total length of sixty-six fathoms. However, any other rope length may be utilized depending upon the needs of the user and without departing from the rope design of the present invention.
The strands of the sinking rope portion are twisted together to provide the desired lay. FIGS. 2b and 3b show the cross-sectional configuration of a three strand rope designed in accordance with the principles of the present invention. If desired, the rope may be formed of a greater number of strands and, if desired, may also be a multi-strand braided rope.
By staggering the terminated blended yarns over a three to four fathom length (typically over a transition region of the order twenty feet) the diameter of the rope is maintained constant through the sinking rope portion, the transition region and the floating rope portion. In an embodiment wherein five to six blended yarns are terminated and replaced by an equal number of 100 percent polyolefin yarns, the individual yarns terminated may be spaced from one another in a staggered fashion so as to be of the order of two to three feet apart, it being understood that each of the blended yarns to be replaced are substituted by 100 percent polyolefin yarn in accordance with the method described hereinabove in conjunction with FIGS. 5a and 5b.
All of the strands of the sinking rope section of the three strand rope may be formed simultaneously and then twisted together to form the cross-section as shown in FIG. 2a. The transitions of each strand may be obtained in the manner described hereinabove and, once the blended yarns have been replaced in the staggered fashion by 100 percent polyolefin yarns, as described hereinabove, the strands of the floating rope section may then be twisted together to form a cross-section as shown in FIG. 3a. It should be noted that the blended yarns not replaced extend the entire length of the rope (sixty-six fathoms, for example). The twisting of the individual strands and the ultimate twisting of the strands forming the multiple strand rope enhance the strength of the rope in the transition region between the sinking and floating rope sections by tightly maintaining the replacement yarns in the strand.
Although the preferred embodiment described herein is preferably formed of polyolefin and polyester fibers, it should be understood that the same technique may be utilized by the employment of fibers having specific gravities which are respectively greater than and less than one and which have abrasion resistance and ultraviolet resistance preferably similar to that of the fibers employed in the rope of the present invention.
A latitude of modification, change and substitution is intended in the foregoing disclosure, and in some instances, some features of the invention will be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the spirit and scope of the invention herein described. | A unique rope for use in commercial fishing comprising floating and sinking portions. The sinking portion has blended yarns made up of a blend of first and second non-metallic synthetic filaments in proportions to yield a sinking rope portion having a specific gravity greater than one. The sinking rope portion comprises strands having yarns of substantially the same diameter. The floating portion of the rope is formed by replacing selected ones of the blended yarns in each strand with yarns formed of a material having a specific gravity of less than one. The replacement yarns and the blended yarns are of the same diameter to enhance the integrity and strength of the rope. The yarns omitted from the sinking section and replaced with the yarns having a specific gravity less than one are terminated at staggered intervals along the rope and their replacement yarns are inserted at like staggered intervals forming a merged region between the sinking and floating portions having a tensile strength which is equivalent to the tensile strength of the sinking and floating portions. The rope material sensitive to ultraviolet radiation is surrounded and thus protected by the material resistant to ultraviolet radiation. The ultraviolet sensitive material may also be treated with a stabilizer material which enhances resistance to ultraviolet radiation. A method is also disclosed for producing the floating/sinking rope. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of Ser. No. 672,742, filed Nov. 19, 1984, which in turn is a continuation-in-part of copending application Ser. No. 492,903, filed May 9, 1983, now U.S. Pat. No. 4,487,769, which in turn is a continuation-in-part of application Ser. No. 385,149 filed June 4, 1982, now abandoned.
FIELD OF THE INVENTION
The present invention refers to mitomycin analogs containing two different amidino groups (Class 260 Subclass 326.24). These compounds are mitomycin C derivatives in which both the quinone amino group and the carbamido nitrogen atom are incorporated within an amidino substituent. These compounds are active antitumor substances against experimental animal tumors.
NOMENCLATURE
The systematic Chemical Abstracts name for mitomycin C is:
[1aR-(1aα,8α,8aβ,8bα)]-6-amino-8-[((aminocarbonyl)oxy)methyl]-1,1a,2,8,8a,8b-hexahydro-8a-methoxy-5-methyl-azirino[2',3',3,4]-pyrrolo[1,2-a]indole-4,7-dione
according to which the azirinopyrroloindole ring system is numbered as follows: ##STR1##
A trivial system of nomenclature which has found wide use in the mitomycin literature identifies the foregoing ring system including several of the characteristic substituents of the mitomycins as mitosane. ##STR2## While this system is convenient and appropriate for a number of simple derivatives such as those bearing N-substituents on the azirino ring nitrogen atom or in the 7- or 9a-positions, it suffers from certain ambiguities and shortcomings for general use. With regard to the compounds of the present invention some of which have substituents on both the azirino ring nitrogen atom and on the side chain carbamoyl nitrogen atom, there is no conventional numbering to distinguish these positions. Therefore, we have chosen in the present specification to refer to the azirino nitrogen atom as N 1a and the carbamoyl nitrogen atom as N 10 in using the mitosane nomenclature system. As to the stereochemical configuration of the products of this invention, it is intended when identifying them by the root name "mitosane" or by structural formula to identify the stereochemical configuration thereof as the same as that of mitomycin C.
DESCRIPTION OF THE PRIOR ART
Mitomycin C is an antibiotic which is produced by fermentation and is presently on sale under Food and Drug Administration approval in the therapy of disseminated adenocarcinoma of the stomach or pancreas in proven combinations with other approved chemotherapeutic agents and as palliative treatment when other modalities have failed (Mutamycin® Bristol Laboratories, Syracuse, N.Y. 13201, Physician's Desk Reference 35th Edition, 1981, pp. 717 and 718). Mitomycin C and its production by fermentation are the subjects of U.S. Pat. No. 3,660,578 patented May 2, 1972 claiming priority from earlier applications including an application filed in Japan on Apr. 6, 1957.
The structures of mitomycins A, B, C, and of porfiromycin were first published by J. S. Webb et al. of Lederle Laboratories Division American Cyanamid Company, J. Amer. Chem. Soc. 94, 3185-3187 (1962).
Recently Shirahata et al., J. Am. Chem. Soc. 1983, 105, 7199-7200 have published convincing evidence as to the absolute configuration of mitomycin C on the basis of X-ray analysis of the N 1a -p-bromobenzoyl derivative thereof. The revised absolute configuration of mitomycin C is as shown in the following formula ##STR3##
SUMMARY OF THE INVENTION
The present invention is concerned with a group of bis-amidino analogs of mitomycin C in which both the 7-amino nitrogen atom and the N 10 -carbamoyl nitrogen atom are part of an amidino substituent. The two amidino groups of these bis-amidino compounds are different. Processes for the preparation of these compounds are included in the present invention. The compounds of the present invention conform to structural Formula I, which also includes compounds wherein the 7-amino nitrogen atom is incorporated within an amidino group, and the N 10 -carbamoyl nitrogen atom is substituted by formyl.
The compounds of Formula I have utility as antitumor agents in that they inhibit the growth of malignant tumors in experimental animals. For this purpose they are administered systemically to a mammal bearing a tumor in a substantially non-toxic antitumor effective dose. The parenteral routes such as the intravenous route of administration are preferred. Disclosed herein are data comparing the present substances in vivo in various experimental animal tumor models with mitomycin C. Based upon these data the appropriate doses of the present substances can be estimated relative to the doses to mitomycin C employed in the treatment of various tumors. The compounds of Formula I are also antibiotics effective against Gram+ and Gram- bacteria. ##STR4##
In Formula I,
R 1 is hydrogen, lower alkyl, lower alkanoyl, benzoyl or substituted benzoyl wherein said substituent is lower alkyl, lower alkoxy, halo, amino, or nitro,
A and B are different and are independently selected from the group having the formula ##STR5## wherein R 2 is hydrogen, lower alkyl, phenyl, lower alkylphenyl, lower alkoxyphenyl, halophenyl, or aminophenyl,
R 3 is lower alkyl, or lower alkoxy,
R 4 is lower alkyl, or
R 3 and R 4 together with the nitrogen atom to which they are attached constitute pyrrolidine, 2-, or 3-lower alkylpyrrolidine, piperidine, 2-, 3-, or 4-lower alkylpiperidine, 2,6-dilower alkylpiperidine, piperazine, 4-substituted piperazine wherein said 4-substituent is alkyl, or carbalkoxy each having 1 to 8 carbon atoms, phenyl, methylphenyl, methoxyphenyl, halophenyl, nitrophenyl, or benzyl, azepine, 2-, 3-, 4-, or 5-lower alkylazepine, morpholine, thiomorpholine, thiomorpholine-1-oxide, or thiomorpholine-1,1,-dioxide, or
B is the amino formyl group.
DETAILED DESCRIPTION OF THE INVENTION
In application Ser. No. 492,903 (U.S. Pat. No. 4,487,769) it was disclosed that treatment of a bis-amidino compound similar to Formula I above in which A and B are each a dimethylaminomethyleneamino group with a primary amine in anhydrous methanol yielded a mitomycin C derivative similar to Formula I above in which A is a mono-substituted amino group corresponding to the amine reactant and B is the NH 2 group. Certain primary amines when employed in that process produce compounds similar to Formula I in which A is the amidino group of the starting material and B is the unsubstituted amino group. In other words, certain primary amines were capable of cleaving the N 10 -amidino group, but not the N 7 -amidino group of the compounds similar to Formula I in which A and B are identical amidino groups. We have now found that secondary amines react with such bis-amidino compounds to replace the amino portion of the B substituent with the amino group corresponding to the secondary amine used in the process. The following equation is illustrative. ##STR6##
In the foregoing equation R 1 , R 2 , R 3 , and R 4 have the definitions given above. R 3' and R 4' are also defined by the same group of terms used to define R 3 and R 4 , but R 3' and R 4' represent different species with respect to R 3 and R 4 in any specific example.
The foregoing process is referred to as the amine exchange method. Substantially, any secondary amine may be employed in the process including alicyclic, cyclic, heteroalicyclic, and heteroaromatic secondary amines with the proviso that they contain no functional substituents which are sterically or chemically incompatible with the reaction conditions. Secondary amines having interfering functional groups may be employed if the functional group is derivatized by a conventional protecting group which may be removed after completion of the reaction. A variety of protecting groups and methods for their removal are known for groups such as hydroxyl, amino, and carboxyl. It is preferred that the carbon atoms attached to the nitrogen atom of the secondary amine reactant be methyl, methylene (--CH 2 --), or methyne (--CH═) carbon atoms. Diisopropylamine has, for example, been found to be non-reactive in the process.
An anhydrous liquid organic compound is employed as reaction medium and any such substance may be employed so long as it is stable and substantially nonreactive to the reactants at the reaction temperature, and does not participtate in the reaction in any other deleterious way. Anhydrous methanol is the preferred reaction medium, but other media such as chloroform, methylene chloride, or other lower haloalkanes and alkanols may be employed. A reaction temperature in the range of from about -15° C. to about +50° C. is preferred. An excess of the amine reactant is preferably employed. By this is meant more than one molecular proportion relative to the bis-amidino mitomycin C derivative used as reactant.
The amide acetal method of Ser. No. 492,903 (U.S. Pat. No. 4,487,769) is also applicable to the preparation of the present compounds by using a compound of the following formula as reactant with the amide acetal according to the method of our prior application. ##STR7##
In the foregoing formula R 1 and A have the same meaning as given above. The entire disclosure of our prior application Ser. No. 492,903 is incorporated herein by reference and including particularly the discussion with respect to the amide acetal method and the identification of various amide acetals that may be employed in the process. More particularly, amide acetals having the following formula are employed. ##STR8## wherein R 2 , R 3 and R 4 have the definitions given with respect to B in claim 1 and R 8 is independently lower alkyl, or cycloalkyl having up to 6 carbon atoms or together they are alkylene forming with the attached oxygen atoms and intervening carbon atom a cyclic structure having 5 or 6 ring members in solution in an anhydrous reaction compatible liquid organic reaction medium at 40° C. to 65° C. until the desired reaction product is formed.
In each of the foregoing processes it is desirable to monitor the course of the reaction by thin layer chromatography by means of which the starting material and product can be distinguished. The optimum reaction time is judged on the basis of disappearance of starting material, appearance of product, or a combination of each particularly in those instances wherein decomposition is a competing reaction.
SPECIFIC EMBODIMENTS
General Procedure
Amine Exchange Method: This method involves reaction of the symmetrical bis-amidino mitosane e.g.: Formula I wherein A and B are identical, with an excess of a secondary amine in anhydrous methanol at ambient temperature. Where possible, the progress of the reaction is monitored by thin layer chromatography. The reaction is terminated by evaporating the solvent and excess reagent under reduced pressure followed by removing the last traces under high vacuum. The resulting syrupy material is subsequently chromatographed to obtain the desired unsymmetrical bis-amidino mitosane which is then fully characterized. Flash chromatography on silica is appropriate, but when the conventional gravity flow method on a silica gel column is employed, degradation to the N 10 -formyl compound sometimes occurs as is discussed more fully below.
Formamide Acetal Method: This method involves reaction of a 7-amidino mitosane e.g.: a compound similar to Formula I wherein B is NH 2 with an appropriate substituted formamide acetal in a methanol-chloroform mixture at ca. 55° C. for up to 72 hours. The progress of reaction is monitored by thin layer chromatography. After the reaction is complete, the reaction mixture is worked up in a similar manner to the above, and pure bis-amidine is obtained after neutral alumina column chromatography.
EXAMPLE 1
7-[(Dimethylamino)methylene]amino-N 10 -(4-morpholinyl)methylene-9a-methoxymitosane ##STR9##
To a solution of 7-[(dimethylamino)methylene]amino-N 10 -(dimethylamino)methylene-9a-methoxymitosane (485 mg, 1.09 mM) is anhydrous methanol (8 ml) was added morpholine (1 ml). After 3 hours the reaction mixture was evaporated on a rotovapor followed by high vacuum. The residue was flash chromatographed (short contact time) on a silica gel column using 5% MeOH in CH 2 Cl 2 . The less polar green material was collected and identified as the title compound (322 mg, 61%). An analytical sample was obtained by precipitating it from a solution of CH 2 Cl 2 and ether with hexane to yield a green amorphous powder.
Anal Calc'd. for C 23 H 30 N 6 O 6 : C, 56.78; H, 6.22; N, 17.27. Found: C, 54.86; H, 6.38; N, 16.18.
IR(KBr, ν max , Cm -1 ): 3440, 3305, 2920, 1675, 1620, 1540, 1445, 1375, 1310, 1275, 1060.
UV(MeOH, λ max , nm): 386 and 248.
NMR(pyridine d 5 , δ): 1.80(br,m,1H), 2.12(s,3H), 2.74(m,1H), 2.84(s,3H), 2.88(s,3H), 3.20(s,3H), 3.20-3.84(m,12H), 4.04 (dd,1H,J=11,4 Hz), 4.39(d,1H,J=14 Hz), 5.04(t,1H), 5.43(dd, 1H,J=11,4 Hz), 7.83(s,1H), 8.38(s,1H).
EXAMPLE 2
7-[(Dimethylamino)methylene]amino-N 10 -(1-piperidinylmethylene)-9a-methoxymitosane ##STR10##
To a solution of 7-[(dimethylamino)methylene]amino-N 10 -(dimethylamino)methylene-9a-methoxymitosane (520 mg, 1.17 mM) in anhydrous methanol was added piperidine (1 ml) and the reaction mixture stirred for 3.75 hours at ca. 22° C. The solvent and excess reagent were removed by first evaporating under reduced pressure on a rotavapor followed by high vacuum. The residue was flash chromatographed (short contact time) on silica gel column employing 5% MeOH in CH 2 Cl 2 as the eluting solvent. The least polar green material was isolated as a green foam (131 mg, 23%) and was identified as the title compound. An analytical sample was obtained by precipitation from methylene chloride-ether-hexane solvent mixture.
Anal Calc'd. for C 19 H 25 N 5 O 5 : C, 59.49; H, 6.66; N, 17.34. Found: C, 58.56; H, 6.89; N, 16.20.
IR(KBr, ν max , Cm -1 ): 3440, 2945, 1675, 1610, 1545, 1450, 1375, 1310, 1255, 1060.
UV(MeOH, λ max , nm): 386 and 246.
NMR (pyridine d 5 , δ): 1.32(brs,6H), 1.92(m,1H), 2.12(s,3H), 2.76(brs,1H), 2.80(s,3H), 3.16(brs,2H), 3.20(s,3H), 3.60 (m,4H), 4.10(dd,1H,J=11,4 Hz), 4.44(d,1H,J=14 Hz), 5.08(t,1H), 5.50(dd,1H,J=11,4 Hz), 7.82(s,1H), 8.46(s,1H).
EXAMPLE 3
7-[(Dimethylamino)methylene]amino-N 10 -(4-morpholinyl)methylene-9a-methoxymitosane
To a solution of 7-[(dimethylamino)methylene]amino-9a-methoxymitosane (116 mg, 0.3 mM) in chloroform (5 ml) and methanol (1 ml) was added morpholine formamide dimethyl acetal (0.6 ml). The reaction mixture was stirred at ca. 55° C. (oil bath) for 48 hours. The progress of the reaction was monitored by silica gel thin layer chromatography (10% MeOH in CH 2 Cl 2 ). At the completion of the reaction, almost all of the starting material (R f =0.43) was converted to the major green material (R f =0.57). The reaction mixture was evaporated on a rotavapor and the resulting oily residue was chromatographed on alumina column (Woelm, Grade III) using CH 2 Cl 2 (50 ml), 1% MeOH in CH 2 Cl 2 (50 ml), then 2% MeOH in CH 2 Cl 2 as eluting solvents. The desired compound (96 mg, R f =0.57) was obtained as an amorphous solid, whose NMR spectrum was identical to the compound described in Example 1.
The following compounds of Formula I wherein A is (CH 3 ) 2 N--CH═N-- and B has the meaning given below may be prepared by substituting the indicated amine for morpholine in Example 1.
______________________________________Example 1 ModificationAmine Reactant B of Product______________________________________Pyrrolidine ##STR11##Thiomorpholine ##STR12##Piperazine ##STR13##Ethyl 1-piperazine- carboxylate ##STR14##Azepine ##STR15##Oxazepine ##STR16##Thiazepine ##STR17##1,3-Diazine ##STR18##1-Methylpiperazine ##STR19##1-Phenylpiperazine ##STR20##______________________________________
The following amide acetals may be substituted for morpholine formamide dimethyl acetal in the procedure of Example 3 to give the corresponding unsymmetrical bis-amidines of Formula I.
N,N-diisopropylformamide diethylacetal
N,N-Dimethylacetamide dimethylacetal
2,2-Dimethoxy-1-methylpyrrolidine
General Procedure for Preparing 7-amidino-N 10 -formyl-9a-methoxymitosanes
The procedure involves the reaction of a 7-amidino mitomycin C derivative with an excess of 4-morpholinyl formamide dimethyl acetal in chloroform at approximately 60° C. for 18 to 48 hours as is illustrated in Example 3. When the 7-amidino functionality is 4-morpholinyl methylene the N 10 -formyl compound can be prepared directly from mitomycin C (see Example 4). Thin layer chromatography (silica gel, 10% MeOH in CH 2 Cl 2 ) of the reaction mixture at the end of the reaction period reveals, that all of the starting material is converted to two faster moving green components. The excess acetal and solvent is removed by evaporation under reduced pressure followed by under high vacuum at approximately 60° C. When the resulting oily residue is chromatographed (drip method) on silica gel rather than alumina as specified in Example 3, degradation to a less polar green material occurs. This is isolated and characterized as the 7-amidino-N 10 -formyl-9a-methoxymitosane compound. The N 10 -formyl compounds are usually isolated as minor products by this method.
EXAMPLE 4
7-[(Morpholylamino)methylene]amino-N 10 -formyl-9a-methoxymitosane ##STR21##
A suspension of mitomycin C (617 mg, 1.85 mM) in chloroform (30 ml) was heated with 4-morpholinyl formamide dimethyl acetal (19.5 ml) at 55° C. for 39 hours. The solvent and excess acetal was removed by evaporation on a rotovapor at 40° C. followed by under high vacuum until approximately 5 ml of oily residue was left. The oily residue was chromatographed on silica gel (40 gm) column packed, employing the slurry method and using CH 2 Cl 2 . The column was eluted with CH 2 Cl 2 (200 ml), 2% MeOH in CH 2 Cl 2 (350 ml) and 5% MeOH in CH 2 Cl 2 (200 ml). Fractions containing the least polar green material were pooled and concentrated. This material was rechromatographed on silica gel column packed with 4% MeOH in CH 2 Cl 2 . Elution with the same solvent, collection, and evaporation of the first green band afforded the title compound as a dark green amorphous solid (50 mg).
Anal. Calc'd for C 19 H 23 N 5 O 6 : C, 54.90; H, 5.48; N, 15.24. Found: C, 52.00; H, 5.44; N, 13.55.
IR (KBr, ν max , cm -1 ): 3420, 3280, 2910, 1755, 1700, 1620, 1540, 1440, 1380, 1305, 1205, 1100, 1060, 1020.
UV (MeOH, λ max , nm): 381 and 229.
NMR (pyridine d 5 , δ): 2.10(s,3H), 2.14(t,1H,J=8 Hz), 2.84 (brs,1H), 3.08(brs,1H), 3.26(s,3H), 3.39(brs,2H), 3.50-3.80 (m,7H), 4.05(dd,1H,J=13,3 Hz), 4.42(d,1H,J=13 Hz), 5.15(t,1H, J=13 Hz), 4.44(dd,1H,J=13,3 Hz), 7.95(s,1H), 9.45(2,1H), 13.1(brs,1H).
EXAMPLE 5
7-[(Dimethylamino)methylene]amino-N 10 -formyl-9a-methoxymitosane ##STR22##
To a solution of 7-[(dimethylamino)methylene]amino-9a-methoxymitosane 379 mg, 0.97 mM) in chloroform was added 4-morpholinyl formamide dimethyl acetal (3.5 ml). The reaction mixture was heated at 55° C. for 18 hours. The process of the reaction was monitored by thin layer chromatography (silica gel, 10% MeOH in CH 2 Cl 2 . The reaction mixture was evaporated on a rotovapor at 40° C. followed by under high vacuum at 60° C. The oily residue was chromatographed on silica gel column packed using CH 2 Cl 2 . Elution with CH 2 Cl 2 (100 ml), 5% MeOH in CH 2 Cl 2 (300 ml) and 10% MeOH in CH 2 Cl 2 (200 ml) afforded two green colored syrups. The faster moving component was rechromatographed on silica gel column packed with 5% MeOH in CH 2 Cl 2 . Elution with the same solvent (250 ml) followed by with 10% MeOH in CH.sub. 2 Cl 2 (250 ml) afforded 40 mg of the less polar amorphous solid green material which was characterized as the title compound.
Anal. Calc'd for C 19 H 23 N 5 O 6 : C, 54.63; H, 5.51; N, 16.77. Found: C, 54.35; H, 5.30; N, 16.15.
IR (KBr), ν max , cm -1 ): 3460, 3300, 2930, 1765, 1710, 1630, 1550, 1440, 1380, 1310, 1210, 1105, 1060
UV (MeOH, λ max , nm): 387 and 233.
NMR (pyridine d 5 , δ): 2.14(2,3H), 2.26(t,1H,J=8 Hz), 2.82(s,4H), 2.90(s,3H), 3.05(brs,1H), 3.28(s,3H), 3.63 (d,1H,J=13 Hz), 4.04(dd,1H,J=13,3 Hz), 4.45(d,1H,J=13 Hz), 5.18(t,1H,J=13 Hz), 5.43(dd,1H,J=13,3 Hz), 7.90(s,1H), 9.45(s,1H), 13.14(brs,1H).
Activity Against P-388 Murine Leukemia
The following table contains the results of laboratory tests with CDF 1 male mice implanted intraperitoneally with a tumor inoculum of 10 6 ascites cells of P-388 murine leukemia and treated with various doses of either a test compound of Formula I or mitomycin C. The compounds were administered by intraperitoneal injection. Groups of six mice were used for each dosage level and they were treated with a single dose of the compound on day one only. A group of ten saline treated control mice was included in each series of experiments. The mitomycin C treated groups were included as a positive control. A 30 day protocol was employed with the mean survival time in days being determined for each group of mice and the number of survivors at the end of the 30 day period being noted. The mice were weighed before treatment and again on day six. The change in weight was taken as a measure of drug toxicity. Mice weighing 20 grams each were employed and a loss in weight of up to approximately 2 grams was not considered excessive. The results were determined in terms of % T/C which is the ratio of the mean survival time of the treated group to the mean survival time of the saline treated control group times 100. The mean survival time for saline treated control animals was nine days. The "maximum effect" in the following table is expressed as % T/C and the dose giving that effect is given. The values in parenthesis are the values obtained with mitomycin C as the positive control in the same experiment. Thus a measure of the relative activity of the present substances to mitomycin C can be estimated. A minimum effect in terms of % T/C was considered to be 125. The minimum effective dose reported in the following table is that dose giving a % T/C of approximately 125. The two values given in each instance in the "average weight change" column are respectively the average weight change per mouse at the maximum effective dose and at the minimum effective dose.
______________________________________Inhibition of P-388 Murine Leukemia Minimum AverageCompound Maximum Effect effective weight(Example No.) % T/C dose.sup.1 dose change.sup.2______________________________________1 222 (172) 6.4 (3.2) 0.1 -0.4; +1.72 194 (172) 6.4 (3.2) 0.4 +0.2; +0.64 175 (270) 3.2 (4.8) <0.4 -0.5; +0.35 170 (270) 3.2 (4.8) 0.4 -1.4; +1.3______________________________________ .sup.1 mg/kg of body weight .sup.2 grams per mouse, days 1-6, at maximum and minimum effective doses
Compounds 1 and 2 were similarly found to provide maximal survival increases greater than mitomycin C in mice bearing B16 melanoma implants. | Symmetrical bis-amidine derivatives of mitomycin C may be converted to unsymmetrical bis-amidine analogs by reaction with secondary amines. The compounds are active anti-tumor agents in experimental animal tumors. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This application is entitled to the benefit of British Patent Application No. GB 0708377.7 filed on May 1, 2007.
FIELD OF THE INVENTION
The present invention relates to a turbomachine blade, for example, a compressor blade for a gas turbine engine and in particular to a fan blade for a gas turbine engine.
BACKGROUND OF THE INVENTION
A turbofan gas turbine engine 10 , as shown schematically in FIG. 1 , comprises in axial flow series an inlet 12 , a fan section 14 , a compressor section 16 , a combustion section 18 , a turbine section 20 and an exhaust 22 . The fan section 14 comprises a fan rotor 24 carrying a plurality of equi-angularly-spaced radially outwardly extending fan blades 26 . A fan casing 28 that defines a fan duct 30 surrounds the fan blades 26 and the fan duct 30 has an outlet 32 . The fan casing 28 is supported from a core engine casing 34 by a plurality of radially extending fan outlet guide vanes 36 .
The turbine section 20 comprises one or more turbine stages to drive the compressor section 18 via one or more shafts (not shown). The turbine section 20 also comprises one or more turbine stages to drive the fan rotor 24 of the fan section 14 via a shaft (not shown).
One known wide chord fan blade is disclosed in US2004/0018091 to the present applicant and is depicted in FIGS. 2 and 3 . The blade 26 comprises a root portion 40 and an aerofoil portion 42 . The root portion 40 comprises a dovetail root, a firtree root, or other suitably shaped root for fitting in a correspondingly shaped slot in the fan rotor, or for mounting to a disk to form a blisk by linear friction welding or other appropriate method. The aerofoil portion 42 has a leading edge 44 , a trailing edge 46 and a tip 48 . The aerofoil portion 42 comprises a concave wall 50 , which extends from the leading edge 44 to the trailing edge 46 , and a convex wall 52 that extends from the leading edge 44 to the trailing edge 46 . The concave and convex walls 50 and 52 respectively comprise a metal for example a titanium alloy. The aerofoil portion 42 has an interior surface 54 and at least a portion, preferably the whole, of the hollow interior 54 of the aerofoil portion 42 is filled with a vibration damping system 56 .
The damping material 56 is a relatively low shear modulus material having viscoelasticity. Viscoelasticity is a property of a solid or liquid which when deformed exhibits both viscous and elastic behaviour through the simultaneous dissipation and storage of mechanical energy. Suitable materials comprise a polymer blend, a structural epoxy resin and liquid crystal siloxane polymer.
One particular and preferred polymer blend comprises, per 100 grams: 62.6% Bisphenol A-Epochlorohydrin (Epophen resin EL5 available from Borden Chemicals, UK); 17.2 grams Amine hardener (Laromin C260 available from Bayer, Germany); 20.2 grams of branched polyurethane (Desmocap 11 available from Bayer, Germany). This polymer blend is then mixed in a mass ratio of 1:1 with a structural epoxy resin, preferably Bisphenol A-Epochlorohydrin mixed with an amine-terminated polymer (e.g. Adhesive 2216 available from 3M).
A fan is susceptible to Foreign Object Damage, or FOD. Composite blades are not as robust as metal blades but offer advantages in terms of reduced mass. Where a hollow blade is provided there is a risk that the blade may burst when impacted by a large object. The use of a viscoelastic filler or core offers damping but also offers a secondary advantage in that the sides of the blade are held together to resist bursting, particularly busting at the trailing edge tip. Blade robustness may be improved through the provision of an internal warren truss arrangement as shown in FIG. 4 where metal girders 60 extend between the concave face 50 and convex face 52 of the aerofoil. The viscoelastic damping material extends around the girders 60
The girders inhibit bursting of the blade upon impact by foreign objects but provide a pathway for the transmittal of vibrational loads through the damping material which can render such damping material obsolete.
SUMMARY OF THE INVENTION
Accordingly, the present invention seeks to provide a novel turbomachine blade that addresses, and preferably overcomes, the above mentioned problems.
According to the invention, there is provided a turbomachine blade comprising a root portion and an aerofoil portion, the aerofoil portion having a leading edge, a trailing edge, a wall for forming a pressure surface extending from the leading edge to the trailing edge and wall for forming a suction wall extending from the leading edge to the trailing edge, wherein the aerofoil portion includes securing means extending between the pressure wall and the suction surface, wherein the securing means and comprising a first extension extending from the suction wall and a second extension extending from the pressure wall, the securing means having an energy absorbing portion comprising a first catch element provided on the first extension and a second catch element provided on the second extension and wherein the first catch element is arranged to engage with the second catch element for absorbing energy after impact to the blade by the foreign object.
Preferably, the pressure wall is concave. The suction wall may be convex.
Preferably, the first catch element and the second catch element are separated from each other by a volume containing a viscoelastic damper.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a first embodiment of a blade provided by the present invention in operational condition.
FIG. 2 is a simplified schematic illustration of a known wide chord saw blade.
FIG. 3 is a second schematic view of the fan blade of FIG. 2 .
FIG. 4 is a simplified schematic illustration, in section, of a known fan blade having an internal warner truss.
FIG. 5 depicts a cross-sectional view of a blade having an internal spring.
FIG. 6 a schematically depicts a cross-sectional view of the blade of FIG. 5 in normal use.
FIG. 6 b depicts a cross-sectional view of the blade of FIG. 5 following an impact when the distance between the pressure and suction flanks increase significantly.
FIG. 7 a depicts a first embodiment of a blade provided by the present invention in operation.
FIG. 7 b is a simplified illustration of the blade of FIG. 7 a after impact from a foreign object.
FIG. 8 depicts a cross-sectional view of a blade in accordance with a second embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A blade as shown in FIG. 5 has an internal spring section 70 that extends between the concave face 50 and convex face 52 . The spring is non-linear and enables vibrations at low strain levels to be accommodated in the viscoelastic damping material 56 . At least one spring element is provided, but where multiple spring elements are present these are provided at equal spacing across the span of the aerofoil that extends between the leading edge 44 and the trailing edge 46 and may be tessellated or interlinked. The springs are aligned with a length that extends generally parallel to the midline 80 of the blade and the majority of the springs are positioned in a region that is towards the tip end as this is the region most prone to failure in the case of soft body foreign object damage.
The damping material 57 is a relatively low shear modulus material having viscoelasticity. Viscoelasticity is a property of a solid or liquid which when deformed exhibits both viscous and elastic behaviour through the simultaneous dissipation and storage of mechanical energy. Suitable materials for the damping layer 57 comprise a polymer blend, a structural epoxy resin and liquid crystal siloxane polymer.
One particular and preferred polymer blend comprises, per 100 grams: 62.6% Bisphenol A-Epochlorohydrin (Epophen resin EL5 available from Borden Chemicals, UK); 17.2 grams Amine hardener (Laromin C260 available from Bayer, Germany); 20.2 grams of branched polyurethane (Desmocap 11 available from Bayer, Germany). This polymer blend is then mixed in a mass ratio of 1:1 with a structural epoxy resin, preferably Bisphenol A-Epochlorohydrin mixed with an amine-terminated polymer (e.g. Adhesive 2216 available from 3M).
It is desirable for the damping material to have a modulus of elasticity in the range 0.5-100 MPa.
The viscoelastic material allows the component to withstand high levels of vibration. The spring element 70 is formed integrally with the convex and concave surfaces and has a thickness 74 of about between 30 □m to 1 mm for an aero-fan blade.
The spring element is formed during manufacture of the blade by powder fed laser deposition where a laser is directed at surface of the blade with sufficient power and focus to form a melt pool thereon into which a powder is supplied and melted. The laser translates across the surface and consequently the melt pool also translates across the surface. As the laser moves from an area to which powder has been added the added powder solidifies to form a deposit having a height. By making repeated passes over an area it is possible to add layers to previously added deposits thereby increasing the overall height of the deposit.
As an alternative the springs may be formed using HIPping using an internal structure or a leachable or etchable support media.
The spring may have other forms as embodied in FIG. 6 . The spring in this embodiment comprises a tubular element, which is secured between the convex face and concave face by flanges 82 . The tube is oval in cross-section with the major axis 84 of the cross section lying substantially parallel to the concave and convex surfaces. Each flange is relatively thin to minimise the transmittal of vibrations.
The tubes preferably run generally radially between the root and the tip though both the length and major axis can be orientated in other directions depending on the damping requirements and/or requirements on structural support. FIG. 6( a ) shows the arrangement in normal use.
Upon impact of foreign objects, the blade may burst or deform with drastic changes to the cross-sectional width of the blade, i.e., the distance between the pressure flank and suction flank increases significantly as depicted in FIG. 6( b ). Upon such an impact the tubular member is stretched to absorb energy and retain the convex and concave surfaces preventing their separation.
In an alternative aspect to the invention, the spring element is replaced with catches. The catches are not connected in normal use and consequently the vibrational transmit path is minimised.
FIG. 7( a ) depicts a first embodiment of a blade provided by the present invention in operational condition. The inside face of the concave surface is provided with a series of integral “T” arms 90 that are interleaved with a series of “T” arms 92 on the inside face of the convex surface. The top bars of the “T” arms overlap the top bars of the interleaved bars such that the underside faces of each bar opposes an underside face of an adjacent, interleaved bar.
FIG. 7( b ) is a simplified illustration of the blade of FIG. 7( a ) after impact from a foreign object. Upon failure of the blade because of impact, the convex face and concave face move apart and the underside of the “T” arms engage to retain the convex and concave surfaces and prevent their separation.
The viscoelastic filler is added by pouring, under a slight positive pressure, the material into the internal cavity of the blade.
In an alternative embodiment of the present invention shown in FIG. 8 , the “T” arms are replaced with interlocking elongate structures with a “mushroom” form cross-section. The head and stalk of opposing “mushrooms” are shaped to provide a constant thickness of viscoelastic damper between them.
The thickness of damping material is related to the damping modulus and has a thickness of between 500 and 1000 μm.
Although the invention has been described with reference to a fan blade 26 , it is equally applicable to a compressor blade.
Although the invention has been described with reference to titanium alloy blades, it is equally applicable to other metal alloy, metal or intermetallic blades. | A turbomachine including securing means that extend between the pressure wall and the suction surface and which includes an energy absorbing portion for absorbing energy after impact to the blade by a foreign object. The energy absorbing portion has a catch that provides the blade with an improved resistance to bursting. | 5 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention relates to a provisional prosthetic system and the surgical methods for utilizing the same.
[0003] 2. Description of the Related Art
[0004] Prostheses are commonly utilized to repair and/or replace damaged bone and tissue in the human body. For example, a knee prosthesis may be implanted to replace damaged or destroyed bone in the tibia and/or femur and to recreate the natural, anatomical articulation of the knee joint. To implant a prosthesis, orthopedic surgery is performed which requires the creation of an incision in the skin of the patient and may necessitate the retraction of surrounding tissue to provide the surgeon with access to the surgical site.
[0005] To facilitate the implantation of a prosthesis, modular prostheses may be utilized. Modular prostheses have several individual, distinct components which are connected together to form the final, implanted prosthesis. For example, a modular knee prosthesis may include individual femoral, tibial, and patellar components which are connected together to form the final, implanted knee prosthesis. Additionally, one component, e.g., a femoral implant in a modular knee prosthesis system, may be selected from several different femoral components having various configurations, all of which are included in the modular prosthesis system. By selecting the femoral component that best accommodates an individual patient's anatomy, the surgeon may assemble a prosthesis that more closely approximates the natural anatomy of the patient.
[0006] In addition to the final, implanted components of a modular prosthesis system, a modular prosthesis system may also include provisional components which replicate the size and shape of the final, implanted components of the modular prosthesis system. The use of provisional components provides the surgeon with the ability to test the ultimate configuration of the prosthesis prior to the implantation of the final components. By trialing, i.e., testing, the surgeon is able to determine whether the fit, alignment, and range of motion provided by the final prosthesis will approximate the patient's natural anatomy. Additionally, as many implants achieve some measure of press fit with the resected bone, it is important that the provisional components maintain similar stiffness to the implant so that implant fit to bone can be checked prior to implantation. To ensure that the provisional components accurately replicate the function of the final, implanted components, the provisional components are dimensionally equivalent to the implanted components and are frequently manufactured from the same material.
SUMMARY
[0007] The present invention relates to a provisional prosthetic system and the surgical methods for utilizing the same. In one embodiment, the provisional prosthetic system replicates the characteristics of corresponding, nonprovisional femoral prostheses. In this embodiment, the provisional prosthetic system includes a frame component and a shell component. The frame component of the provisional prosthetic system may be configured to be attached directly to a resected femur. In one exemplary embodiment, the frame component is impacted onto the resected femur to firmly seat therewith. Once the frame component is secured to the resected femur, the shell component of the provisional prosthetic system may be positioned on and secured to the frame component. In one exemplary embodiment, the frame component is made from a metallic material. This allows for the frame component to maintain the rigidity necessary to facilitate proper trialing. In another exemplary embodiment, the shell component is a plastic. In yet another exemplary embodiment, the shell component is fabricated by injection molding.
[0008] To ensure that a provisional and, ultimately, a nonprovisional that has the characteristics most suited for an individual patient are selected, the provisional prosthetic system may include a plurality of shell components having different characteristics, e.g., different sizes, orientations, and/or designs that correspond to available nonprovisional prostheses. For example, if the prosthesis includes three different nonprovisional implants having different sizes, three provisional implants would be included in the prosthesis system which correspond in size to the three nonprovisional implants. Thus, a surgeon may attach a first shell component to the frame component of the provisional prosthetic system and trial, i.e., test, the same. If the surgeon is not satisfied with the results of the current shell component, the surgeon may remove the shell component from the frame component and attach a different shell component having different characteristics, until the best fit for an individual patient is identified.
[0009] By utilizing the provisional prosthetic system of the present invention, numerous benefits are realized. For example, by utilizing the frame component and shell component design of the present system, only a single frame component is attached to the resected femur. Thus, the need to impact and remove various provisional components from the resected bone is eliminated and wear of the natural bone stock during the trialing of the provisional components is lessened. Additionally, by eliminating the need to manufacture the shell components of the provisional prosthetic system from a metallic material, the weight of the full complement of provisional components is substantially lessened. This decreases the burden on operating room personnel and hospital staff to stock, inventory, clean, and transport the full complement of provisional components. Moreover, by manufacturing the shell components of the present provisional system from plastic, for example, the cost of producing the same is decreased.
[0010] Further, because a plurality of different shell components may be attached to a single frame component, the total number of provisional components in any given provisional system may be decreased. For example, in an implant system having femoral components for standard size, plus size, and minus size for each of the left knee and the right knee, a single frame component may be designed to accept all six configurations of the corresponding shell components. Thus, a single frame can be combined with the differing shell components to form provisional components that accurately replicate the characteristics of the six corresponding nonprovisional implants.
[0011] By providing a full complement of provisional components having a mass and volume substantially less than that of a complement of standard provisional components, a hospital may be more likely to stock the entire system. Additionally, a surgeon may request the entire complement of components in the operating room and thus the surgeon may be able to achieve better extension and flexion gap balancing, without the need to perform additional bone cuts or to extensively test the flexion and extension gaps.
[0012] In one form thereof, the present invention provides a modular provisional system, including a frame component configured to be secured to the distal end of a femur; and a shell component configured to be releaseably secured to the frame component, the frame component and the shell component cooperating to form a provisional implant which replicates the characteristics of at least one nonprovisional component of a prosthesis system.
[0013] In another form thereof, the present invention provides a modular provisional system, including a frame component having first engagement structure, the frame component configured for securement to the distal end of a femur; and a shell component having a frame contacting surface and an articulation surface, at least a portion of the frame contacting surface configured to engage the first engagement structure of the frame component to secure the shell to the frame, the articulation surface of the shell component shaped to replicate natural femoral condyles, wherein the frame component and the shell component cooperate to replicate a characteristic of at least one nonprovisional component of a prosthesis system.
[0014] In another form, thereof the present invention provides a method of trialing a femoral implant including the steps of attaching a frame component to the distal end of a femur; attaching a shell component having an articulation surface to the frame component, wherein the frame component and the shell component cooperate to form a first provisional implant; trialing the first provisional implant formed by the frame component and the shell component.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:
[0016] FIG. 1 is an exploded perspective view of one embodiment of the provisional prosthetic system and depicting a resected femur;
[0017] FIG. 2 is another perspective view of the embodiment of FIG. 1 , taken from a posterior aspect;
[0018] FIG. 3 is another perspective view of the embodiment of FIG. 1 taken from a medial aspect;
[0019] FIG. 4 is an exploded perspective view of the provisional prosthetic system according to another exemplary embodiment; and
[0020] FIG. 5 is an assembled, perspective view of the provisional prosthetic system of FIG. 4 ;
[0021] FIG. 6 is a partial assembled view of the provisional prosthetic system of FIG. 1 ; and
[0022] FIG. 7 is an assembled view of the provisional prosthetic system of FIG. 1 .
[0023] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrates preferred embodiments of the invention and such exemplifications are not to be construed as limiting the scope of the invention any manner.
DETAILED DESCRIPTION
[0024] As shown in FIGS. 1-3 , femoral provisional 10 includes frame component 12 and shell component 14 . Shell component 14 may be attached to frame component 12 , as shown in FIG. 7 , to form assembled femoral provisional 10 , as described in detail below. Referring to FIGS. 1-3 , frame component 12 of femoral provisional 10 is configured for direct attachment to femur 16 . As shown in FIG. 1 , femur 16 includes resected distal end 18 having apertures 20 and cutout 22 formed therein. Resected distal end 18 of femur 16 is fully resected, i.e., all of the cuts necessary for implantation of a final, nonprovisional femoral component have been made. In another exemplary embodiment, resected distal end 18 may include only a portion of the cuts necessary to facilitate implantation of the final, nonprovisional femur component. In this embodiment, femoral provisional 10 may be utilized to facilitate a surgeon's determination of the location for making the remaining cuts to femur 16 .
[0025] In one exemplary embodiment, frame component 12 is formed from a metallic material, e.g., formed from a metal, a metal alloy, or a material having properties that are substantially similar to a metal or metal alloy. This provides frame component 12 with the necessary rigidity to represent the rigidity of the corresponding nonprovisional component on the resected bone and retain shell component 14 in the proper position during trialing. Frame component 12 of femoral provisional 10 includes bone contacting surface 24 and posts 26 , best seen in FIG. 2 . Bone contacting surface 24 of frame component 12 is shaped to mate with resected distal end 18 of femur 16 and posts 26 are sized to be received within apertures 20 . Apertures 20 of femur 16 may be formed by drilling, reaming, or any other known technique. Apertures 20 are sized slightly larger than posts 26 , but are close enough in size to posts 26 that frame component 12 may be impacted to be properly seated on distal end 18 of femur 16 . While frame component 12 is described and depicted herein as including posts 26 , posts 26 are not necessary to the function of frame component 12 and further embodiments are envisioned in which posts 26 are absent.
[0026] Frame component 12 further includes shell contacting surface 27 having condylar bases 28 , 30 connected by anterior bridge portion 32 and posterior bridge portion 34 ( FIG. 3 ). In one exemplary embodiment, posterior bridge portion 34 replicates the cam of a Posterior Stabilized femoral implant. In another exemplary embodiment configured for a Posterior Cruciate Ligament Retaining femoral prosthesis, posterior bridge portion 34 is absent. Additionally, ribs 36 , 38 extend from shell contacting surface 27 of frame component 12 to add rigidity and facilitate retention and alignment of shell component 14 upon frame component 12 , as discussed in detail below.
[0027] Referring to shell component 14 , shell component 14 includes posterior overhang 42 , anterior overhang 43 ( FIG. 2 ), and frame contacting surface 40 forming condylar recesses 44 . Condylar recesses 44 are separated from overhangs 42 , 43 by tapered leads 46 , 47 , respectively, which facilitate attachment of shell component 14 to frame component 12 . In one exemplary embodiment, shell component 14 is formed from a plastic. For example, shell component 14 may be formed from an injection molded polymer. By forming shell component 14 from a plastic or other polymer, the weight of shell component 14 and, correspondingly, femoral provisional 10 is significantly reduced. Thus, a full complement of provisional components made in accordance with the present invention is significantly lighter than a full complement of standard provisional components, lessening the burden on operating room personnel and hospital staff who must transport the same.
[0028] Shell component 14 also includes articulating surface 48 having condylar portions 50 , 52 connected by anterior portion 54 . Referring to FIG. 2 , shell component 14 further includes grooves 56 , 58 extending through frame contacting surface 40 and overhang 43 . Grooves 56 , 58 are configured to receive and retain ribs 36 , 38 of frame component 12 , respectively, therein. Additionally, both grooves 56 , 58 include an indentation (not shown) configured to matingly engage ribs 36 , 38 , respectively. Thus, receipt of ribs 36 , 38 within the indentations of grooves 56 , 58 provide for retention of anterior portion 54 of shell component 14 upon anterior bridge portion 32 of frame component 12 . In one exemplary embodiment, the engagement of ribs 36 , 38 with grooves 56 , 58 forms a snap-fit connection. Moreover, ribs 36 , 38 and grooves 56 , 58 facilitate the alignment and seating of shell component 14 with frame component 12 prior to attachment.
[0029] Referring to FIGS. 1-3 , condylar recesses 44 ( FIGS. 1 and 2 ) of shell component 14 are configured to receive portions of condyle bases 28 , 30 of frame component 12 therein. Specifically, condylar recesses 44 and tapered lead 46 are configured to engage posterior portions 60 , 62 and tapered edge 64 ( FIG. 2 ), respectively. Thus, posterior portions 60 , 62 and condylar bases 28 , 30 of frame component 12 are in posterior mating engagement with condylar recesses 44 and tapered lead 46 of shell component 14 . In one exemplary embodiment, the interaction of condylar recesses 44 , tapered lead 46 , posterior portions 60 , 62 and tapered edge 64 forms a snap-fit connection. To remove shell component 14 from frame component 12 , a surgeon simply lifts up on anterior portion 54 of shell component 14 , for example, to release the snap-fit connection. Shell component 14 may then be replaced by another shell component 14 having different characteristics.
[0030] To assemble femoral provisional 10 upon femur 16 , femur 16 is initially resected, as described above, to form resected distal end 18 . Apertures 20 are then formed in resected distal end 18 of femur 16 and sized to receive post 26 of frame component 12 therein. In one exemplary embodiment, frame component 12 is selected from a plurality of frame components having different characteristics. With post 26 aligned with apertures 20 , frame component 12 is impacted onto resected distal end 18 of femur 16 until bone contacting surface 24 is in mating engagement with resected distal end 18 , as shown in FIG. 6 . Referring to FIGS. 6 and 7 , once frame component 12 is securely seated on femur 16 , one of a plurality of shell components 14 having characteristics which a surgeon believes would best accommodate a patient's natural anatomy is aligned with and secured to frame component 12 , as described in detail above. Alternatively, one of a plurality of shell components 14 may be secured to frame component 12 prior to seating frame component 12 on femur 16 . Thus, once frame and shell components, 12 , 14 are secured together, the assembly is impacted on femur 16 as described above. With shell component 14 secured to frame component 12 and, correspondingly, femur 16 , a surgeon may perform trialing of femoral provisional 10 .
[0031] In the event the surgeon determines that femoral provisional 10 satisfactorily replicates the patient's natural anatomical movement, shell component 14 may be removed from frame component 12 and frame component 12 removed from femur 16 . A nonprovisional femoral component having characteristics which correspond to femoral provisional 10 is then implanted using standard surgical techniques.
[0032] In the event a surgeon determines femoral provisional 10 does not satisfactorily replicate a patient's natural anatomical movement, shell component 14 may be removed from frame component 12 , which provides the sole securement of shell component 14 to femur 16 as described in detail above, and a different shell component 14 having different characteristics may be attached to the same frame component 12 . By using a single frame component 12 capable of attachment to multiple shell components 14 , the need to impact and remove various frame components 12 is eliminated. Thus, wear of resected distal end 18 of femur 16 is lessened. Additionally, by providing for attachment of multiple shell components 14 to a single frame component 12 , the total number of components is lessened. The surgeon may then trial the new femoral provisional 10 . Once a surgeon has identified the one of a plurality of shell components 14 that would satisfactorily replicate the patient's natural anatomical movement, femoral provisional 10 may be removed from femur 16 , as described in detail above, and the corresponding nonprovisional femoral component implanted.
[0033] Referring to FIG. 4 , another exemplary embodiment of frame component 12 and shell component 14 are depicted as frame component 70 and shell component 72 . Frame component 70 and shell component 72 include several components which are identical or substantially identical to components of frame component 12 and shell component 14 , respectively, and corresponding reference numerals are used to identify identical or substantially identical components therebetween. As shown in FIG. 4 , frame component 70 includes openings 74 formed in condylar bases 28 , 30 and anterior bridge portion 32 . Similarly, shell component 72 includes projections 76 formed on condylar portions 50 , 52 and anterior portion 54 . Projections 76 are sized and configured to be received with openings 74 of frame component 70 . Thus, as shown in FIG. 5 , receipt of projections 76 of shell component 72 within openings 74 of frame component 70 provides a snap-fit connection between frame component 70 and shell component 72 .
[0034] To separate frame component 70 and shell component 72 , a surgeon may exert a force on anterior portion 54 of shell component 72 , in a direction away from frame component 70 , to disengage one of projections 76 from one of openings 74 . Once shell component 72 is removed from frame component 70 , a different shell component 72 having different characteristics may be attached to frame component 70 in a similar manner. In another exemplary embodiment, frame component 70 may include a projecting rib and shell component 72 a corresponding groove to facilitate alignment of frame component 70 and shell component 72 to facilitate proper seating and retention of shell component 72 on frame component 70 .
[0035] While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | A provisional prosthetic system that replicates the characteristics of a corresponding, nonprovisional femoral prosthesis. The provisional prosthetic system may include a frame component and a shell component. The frame component of the provisional prosthetic system may be configured to be attached directly to a resected femur. In one exemplary embodiment, the frame component is impacted onto the resected femur to firmly seat therewith. Once the frame component is secured to the resected femur, a shell component of the provisional prosthetic system may be positioned on and secured to the frame component. In one exemplary embodiment, the frame component is made from a metallic material. This allows for the frame component to maintain the rigidity necessary to facilitate proper trialing. In another exemplary embodiment, the shell component is a plastic. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to column support structures and more particularly pertains to a sealed marine post for resisting deterioration within a body of water.
2. Description of the Prior Art
The use of column support structures is known in the prior art. More specifically, column support structures heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
Known prior art column support structures include U.S. Pat. No. 3,467,490; U.S. Pat. No. 3,813,837; U.S. Pat. No. 3,969,557; U.S. Pat. No. 4,007,075; U.S. Pat. No. 4,262,047; and U.S. Pat. No. 4,584,210.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a sealed marine post for resisting deterioration within a body of water which includes a central post member wrapped in a fiber mesh and sealed within a matrix resin, with a mounting cap for facilitating coupling of the post to a pier structure and a guide cap for facilitating forced insertion of the post into a sea bed.
In these respects, the sealed marine post according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of resisting deterioration within a body of water and supporting a pier or dock structure.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of column support structures now present in the prior art, the present invention provides a new sealed marine post construction wherein the same can be utilized for resisting deterioration within a body of water. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new sealed marine post apparatus and method which has many of the advantages of the column support structures mentioned heretofore and many novel features that result in a sealed marine post which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art column support structures, either alone or in any combination thereof.
To attain this, the present invention generally comprises a post for resisting deterioration within a body of water. The inventive device includes a central post member wrapped in a fiber mesh and sealed with a matrix resin. A mounting cap for facilitating coupling of the post to a pier structure and a guide cap for facilitating forced insertion of the post into a sea bed can also be provided.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the 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 such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an object of the present invention to provide a new sealed marine post apparatus and method which has many of the advantages of the column support structures mentioned heretofore and many novel features that result in a sealed marine post which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art column support structures, either alone or in any combination thereof.
It is another object of the present invention to provide a new sealed marine post which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new sealed marine post which is of a durable and reliable construction.
An even further object of the present invention is to provide a new sealed marine post which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such sealed marine posts economically available to the buying public.
Still yet another object of the present invention is to provide a new sealed marine post which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
Still another object of the present invention is to provide a new sealed marine post for resisting deterioration within a body of and supporting a dock or pier structure relative thereto.
Yet another object of the present invention is to provide a new sealed marine post which includes a central post member wrapped in a fiber mesh and sealed within a matrix resin, with a mounting cap for facilitating coupling of the post to a pier structure and a guide cap for facilitating forced insertion of the post into a sea bed.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is an isometric illustration of a plurality of sealed marine posts according to the present invention in use.
FIG. 2 is an isometric illustration of an individual post of the invention.
FIG. 3 is an isometric illustration of a mounting means comprising a portion of the invention.
FIG. 4 is an isometric illustration of an alternative form of the mounting means.
FIG. 5 is an isometric illustration of a construction of the present invention.
FIG. 6 is a further isometric illustration of the construction of the invention.
FIG. 7 is a cross sectional view taken along line 7--7 of FIG. 2.
FIG. 8 is an exploded frontal elevation view of the invention including a guide means.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIGS 1-8 thereof, a new sealed marine post embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
More specifically, it will be noted that a plurality of the sealed marine posts 10 can be utilized to support a pier structure 12, as shown in FIG. 1 of the drawings. The sealed marine posts 10 are each configured to be inserted into a sea bed of a body of water so as to project above a water line thereof. A mounting means `L` can be secured to a top end of each of the posts 10 to facilitate coupling of the sealed marine posts to a pier structure 12 or other structure to be supported relative to a body of water.
Referring now to FIGS. 5 through 7, it can be shown that the sealed marine post 10 of the present invention preferably comprises an elongated central post member 16 having a longitudinal axis `L` directed therethrough. The central post member 16 is preferably comprised of wood, but may be alternatively comprised of tubular steel, aluminum, or other structures. The wooden central post member 16 can be treated with various anti-deterioration compounds including pressure applied CCA compounds conventionally known in the art. A first mesh layer 18 is wrapped about the central post member 16 and includes a plurality of orthogonally oriented fibers which extend parallel and orthogonal relative to the longitudinal axis `L` of the central post member 16. A first matrix resin layer 20 impregnates the first mesh layer 18 and bonds with the central post member 16. A second mesh layer 22 is wrapped about the central post member 16 on top of the first matrix resin layer 20 as shown in FIG. 6 of the drawings. The second mesh layer 22 includes orthogonally oriented fibers which extend at an oblique angle relative to the longitudinal axis `L` of the central post member 16 so as to impart further strength and rigidity to the central post member relative to the first mesh layer 18 as a result of the oblique angular orientation between the fibers of the first mesh layer 18 and the fibers of the second mesh layer 22. A second matrix resin layer 24 impregnates the second mesh layer 22 and bonds with the first matrix resin layer 20 thereof. If desired, the first and second mesh layers 18 and 22 can be wrapped on top of one another during manufacture of the device 10, wherein a single matrix resin layer is then applied to both mesh layers to simultaneously impregnate the same and bond with the central post member 16.
As shown in FIG. 7, the present invention 10 further comprises a first upper mesh panel 26 extending substantially orthogonally across an upper end of the central post member 16. The first upper mesh panel 26 is similarly impregnated with the first matrix resin layer 20 so as to seal the upper end of the central post member 16. A second upper mesh panel 28 can also extend across the upper end of the central post member on top of the first upper mesh panel 26 to be impregnated with the second matrix resin layer 24. Preferably, the first upper mesh panel 26 includes orthogonally oriented fibers, with the second upper mesh panel 28 including orthogonally oriented fibers which are positioned at an oblique angle relative to the fibers of the first upper mesh panel 26. In a similar manner, a first lower mesh panel 30 extends substantially orthogonally across a lower end of the central post member 16 and is impregnated with the first matrix resin layer 20. A second lower mesh panel 32 extends over the first lower mesh panel 30 and is impregnated with the second matrix resin layer 24. The first lower mesh panel 30 includes a plurality of orthogonally fibers which are positioned at an oblique angle relative to orthogonally oriented fibers of the second lower mesh panel 32. By this structure, the entire central post member 16 is encapsulated by the mesh layers 18 and 22 and sealed with the matrix resin layers 20 and 24 so as to preclude an entrance of sea water thereinto, thereby substantially extending a life of the central post member 16.
Referring now to FIGS. 2 through 4, it can be shown that the mounting means 14 facilitating coupling of the post to a pier structure 12 preferably comprises a cylindrical receiver 34 which can be circumferentially positioned about the upper end of the central post 16 and over the mesh layers 18 and 22 thereof. A mounting plate 36 extends orthogonally across an upper end of the cylindrical receiver 34 and includes a plurality of unlabeled mounting apertures directed therethrough permitting securement of the mounting plate 36 to a lower portion of the pier structure 12. The cylindrical receiver 34 can be adhesively secured to the upper end of the central post member 16, or alternatively may include a plurality of mounting apertures directed therethrough permitting a passage of threaded fasteners (wrapped with the matrix resin fibers to seal such fasteners) or the like through the cylindrical receiver 34 for securement into the central post member 16. As shown in FIG. 4, the mounting means 14 may further comprise a first mounting flange 38 projecting substantially orthogonally from the mounting plate 36, and a second mounting flange 40 similarly projecting substantially orthogonally from the mounting plate. The mounting flanges 38 and 40 are preferably orthogonally oriented relative to one another so as to define a corner coupling which can be positioned at a juncture of two intersecting joists of the pier structure 12. By this structure, the mounting means 14 permits ease of coupling of the pier structure 12 to the individual posts 10 supporting the same as shown in FIG. 1 of the drawings.
Referring now to FIG. 8, it can be shown that the present invention 10 may further comprise a guide means 42 coupled to a lower end of the central post member 16 by an adhesive 44 as interposed therebetween for facilitating guiding of the post 10 during forced insertion thereof into a sea bed. To this end, the guide means 42 preferably comprises a lower cylindrical receiver 46 which can be circumferentially positioned about a lower end of the central post member 16 and the mesh layers 18 and 22 wrapped thereabout. A conical guide member 48 projects from the lower cylindrical receiver 46 and defines an unlabeled pointed end which can be forced into the sea bed during insertion of the post 10 thereinto so as to facilitate ease of such insertion.
In use, the sealed marine post 10 according to the present invention can be easily utilized to support a pier structure 12 as shown in FIG. 1 of the drawings. Because the central post member 16 is sealed beneath the mesh layers 18 and 22 and the resin layers 20 and 24, deterioration of the central post member 16 is substantially reduced and/or eliminated. Preferably, the mesh layers 18 and 22 comprise a fiberglass, with the matrix resin layers 20 and 24 comprising a conventionally known catalyzed resin.
As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A post for resisting deterioration within a body of water. The inventive device includes a central post member wrapped in a fiber mesh and sealed within a matrix resin. A glow in the dark or fluorescent painted mounting cap for facilitating coupling of the post to a pier structure and a guide cap for facilitating forced insertion of the post into a sea bed can also be provided. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to jet engines, and more specifically but not by way of limitation, to a hypersonic jet engine operable in a pulsejet mode, a ramjet mode, and a chemical rocket mode, in part, by utilizing front and rear air flow gates.
BACKGROUND
[0002] In the aircraft industry, there is always a desire to improve an aircnifts ability to fly faster, farther and with more fuel efficiency, per passenger. As such, there is a desire in the industry to be able to have supersonic and hypersonic flights, with aircraft that have fuel consumption better than turbofan-propelled jumbo-jet aircraft (whose size is similar to that of a Boeing™ 747).
[0003] The desire and need for improved speed, range and fuel efficiency is not limited to the aircraft industry. As can be appreciated, it also extends into the spacecraft industry.
[0004] Accordingly there is a need for an aircraft engine capable of moving large aircraft at hypersonic speeds while having fuel consumption much lower than that of a turbofan-propelled aircraft of similar size.
SUMMARY OF THE INVENTION
[0005] The present invention provides a hypersonic jet engine able to start in air-breathing mode, on its own, from zero speed without a compressor. The hypersonic jet engine is further able to fly an aircraft at and faster than Mach 6 without using the scramjet method of combustion, while maintaining a fuel economy equal to or better that that of a turbofan engine. The present invention is operable in a pulsejet mode, a ramjet mode, and chemical rocket mode, and utilizes front and back airflow gates driven by DC motors or electromagnetic fields to regulate the intake and exhaust of the engine.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] A more complete understanding of the present invention may be had by reference to the following Detailed Description and appended claims when taken in conjunction with the accompanying Drawings wherein:
[0007] FIG. 1 illustrates a perspective view of an engine mounted to a wing of an aircraft in accordance with the principles of the present invention;
[0008] FIGS. 2-5 illustrate cross-sectional views of a preferred embodiment of the present invention in various operating modes taken along line A-A of FIG. 1 ;
[0009] FIG. 6 illustrates a partial cross-sectional side view of the interior of the engine at the combustor ring;
[0010] FIG. 7 illustrates a front view of a preferred embodiment of the present invention; and
[0011] FIG. 8 illustrates a cross-sectional side view of a preferred embodiment of a ramjet combustor.
DETAILED DESCRIPTION
[0012] Referring now to the drawings submitted herewith, wherein various elements depicted are not necessarily drawn to scale, and where like elements in various views are depicted with identical element numbers, and in particular to FIG. 1 , there is illustrated a perspective view of a preferred embodiment of a hyperjet 100 in accordance with the principles of the present invention. Hyperjet 100 is illustrated attached to the underside of wing 210 of an aircraft 202 .
[0013] Referring now to FIGS. 2-5 , there is illustrated a side cross-sectional view taken along line A-A of FIG. 1 , illustrating the interior components of hyperjet 100 . As described in more detail herein, hyperjet 100 is operable in various modes, including a pulsejet mode, a ramjet mode, and chemical rocket mode.
[0014] As illustrated, hypedjet 100 includes an exterior casing 102 for housing the components therein. Disposed within exterior casing 102 is an interior casing and fuel injector housing 104 . Airflow gate assemblies 106 and 108 are also disposed within exterior casing 102 , with airflow gate assembly 106 being positioned at the intake end of hyperjet 100 and airflow gate assembly 108 being positioned at the exhaust end of hyperjet 100 . Airflow gate assemblies 106 and 108 are hollow spheres containing a pipe as wide as the interior diameter of the hypedjet 100 . DC motors 110 and 112 are connected to airflow gates assemblies 106 and 108 respectively. A ramjet combustor ring 114 is positioned proximate to airflow gate assembly 106 , with ramjet combustor ring 114 made up of a plurality of ramjet burners 116 .
[0015] Airflow gate assembly 106 includes gate 120 and a flow path 124 , and airflow gate assembly 108 includes gate 126 and flow path 130 .
[0016] In pulsejet mode, airflow gate assemblies 106 and 108 facilitate complete combustion within hyperjet 100 , with airflow gate assemblies 106 and 108 being open and closed by DC motors 110 and 112 . Airflow gate assemblies 106 and 108 are configured in a piped sphere configuration, which does not produce unnecessary shape changes in movement. This helps to facilitate supersonic flight as a result of the drag/shockwave reduction due to the shapes of the airflow gate assemblies 106 and 108 . It is comtemplated that the airflow gate assemblies 106 and 108 could be either pilot or computer controlled. This allows for a more accurate account for ambient air pressure and temperature changes during flight. Upon being exhausted from airflow gate 108 through supersonic nozzle 118 , the combusted gas pressure is to be as close as possible to ambient air pressure. This facilitates the avoidance of shockwave formation at the rear of hyperjet 100 at supersonic speeds.
[0017] Referring now to FIG. 6 , there is illustrated a partial cross-sectional side view of the interior of hypejet 100 behind airflow gate 106 showing airflow through and about hyperjet 100 at combustor ring 114 . As illustrated, a portion of airflow 300 enters the main burner 200 of hyperjet 100 , while another portion 302 of air flow 300 enter the ramjet burners of ramjet combustor ring 114 . Fuel Injectors 132 inject and mix fuel with airflow 302 in each of the ramjet burners 116 (see FIG. 7 ) of ramjet combustor ring 114 . Airflows 302 and 300 then flow towards the exhaust of hyperjet 100 .
[0018] Referring now to FIG. 7 , there is illustrated a frontal view of hyperjet 100 with airflow gate 106 in the open position such that flow path 124 permits airflow into hyperjet 100 . As illustrated, when airflow gate 106 is in the open position, airflow is permitted to enter both the ramjet combustor ring 114 and the center or main burner portion 200 of hyperjet 100 . DC motor 110 is configured within hyperjet 100 to operate the opening and closing of airflow gate 106 . Similarly, DC motor 112 is configured within hyperjet 100 to operate the opening and closing of airflow gate 108 .
[0019] Referring now to FIGS. 6 and 7 , combustor ring 114 is comprised of a collective of ramjet burners or combustors 116 . Ramjet combustors 116 function only when hyperjet 100 is operating in ramjet mode. When operating in ramjet mode, hyperjet 100 has a performance increase similar to the performance increase offered by the turbofan over the turbojet. In this preferred embodiment, the number of ramjet combustors 116 is always an even number; with the ramjet combustors 116 functioning in symmetrically oriented pairs in order to keep the overall airflow direction parallel to the direction of hyperjet 100 .
[0020] Referring now to FIG. 8 , there is illustrated a sectional side view of a ramjet burner 116 of ramjet combustor ring 114 . As illustrated, casing 134 generally tapers from each end of ramjet burner 116 towards the center of ramjet burner 116 , forming a throat portion 136 . It is at the throat portion 136 where the fuel injection and combustion take place in ramjet burner 116 . Arrow 304 illustrates typical airflow through ramjet burner 116 during operation.
[0021] As mentioned herein, hyperjet 100 is operable in various modes, including a pulsejet mode, a ramjet mode, and chemical rocket mode. Referring now to FIGS. 1-8 , a more detailed description of each of these modes will now be described.
[0022] When operating in pulsejet mode, first airflow gates 106 and 108 are both closed (See FIG. 2 ), whereby air is enclosed in the main burner portion 200 of hypedjet 100 . Fuel is then injected and detonated in the main burner portion 200 of hypedjet 100 , creating the pulse. The main burner portion 200 of hypersonic engine 100 acts as a close-volume pressure vessel. Then gate 108 open, while gate 106 remains closed (See FIG. 3 ). As a result of the detonation of the fuel injected into the main burner portion 200 of hypersonic engine 100 and the pressure created therein, the high-temperature and high-pressure is then exhausted from hyperjet 100 through supersonic nozzle, creating thrust.
[0023] With airflow gate 108 remaining open, airflow gate 106 then opens (See FIG. 4 ), permitting the influx of air into hyperjet 100 through airflow gate 106 .
[0024] Airflow gate 108 , then closes (See FIG. 5 ), whereby the main burner portion 200 of hypersonic engine 100 becomes filled with air at the maximum possible pressure (i.e. stagnation). Once filled with air, the cycle repeats.
[0025] Good results have been achieved with the operation of hyperjet 100 in pulsejet mode when both airflow gates 106 and 108 spin at a steady or constant speed.
[0026] When hypedjet 100 is operating in ramjet mode, both airflow gates 106 and 108 are maintained in the open position, such as is illustrated in FIG. 4 . In ramjet mode, combustion of fuel is carried out in the ramjet burners 116 of ramjet combustor ring 114 (see FIG. 8 ) instead of in the main burner 200 of hyperjet 100 . At supersonic speeds, incoming air is slowed into ramjet burners 116 to Mach 1 and gains pressure and temperature in the process. The incoming air reacts with the fuel at Mach 1, is combusted and then exhausted into the main burner area 200 at the same speed as the incoming air (See FIG. 6 ). This keeps very high pressure and temperature differences from the incoming air. Good results have been achieved by maintaining straight orientation of the exhaust gas by using ram et burners 116 in pairs opposite each other. The incoming air 300 becomes mixed with the high pressure-and-temperature gas 302 and then becomes exhausted such that the exhaust pressure matches the ambient air pressure at an exhaust speed/temperature combination which creates the desired sufficient thrust. In this embodiment, only 20% of the incoming air is burned, which accomplishes about 80% fuel savings over existing ramjets.
[0027] When hyperjet 100 is operating in chemical rocket mode, airflow gate 106 is maintained in the closed position, while airflow gate 108 is maintained in the open position (See FIG. 3 ). In chemical rocket mode, an independent air/oxygen supply is required as airflow gate 108 is in the closed position, inhibiting air intake into jet engine 100 . In this embodiment, hyperjet 100 can be switched to chemical rocket mode at any speed. Hyperjet 100 can be switched from rocket mode to pulsejet mode if the speed is below Mach 1.85. Hyperjet 100 can be switched to ramjet mode if the speed is above Mach 2. Hyperjet 100 can be switched from chemical rocket mode to either ramjet mode or pulsejet mode if the speed is at or between Mach 1.85 and Mach 2.
[0028] It is contemplated to be within the scope of this invention that the hyperjet 100 described herein is not limited to use on aircraft, but could also be used in other type of crafts and vehicles, such as, but not limited to speedboats.
[0029] The following illustrates the mathematical model of the operation of hyperjet 100 :
[0030] It is noted that only metric units of measure are being used.
[0031] Nomenclature:
[0000] Symbol Meaning
[0000]
f Stoichiometric fuel-to-air mass ratio.
T a Actual ambient temperature.
T 0a Tea Total (stagnation) ambient temperature.
T 04 Maximum (stagnation) temperature generated by combustion.
Q R Fuel heating value; average 45 MJ/kg for fuel “JP4”.
c p Specific heat of air at constant pressure; 1003.5 J/(kg*K)
c v Specific heat of air at constant volume; 716.8 J/(kg*K)
R Perfect gas constant; 287 J/(kg*K)
H R Specific heat ratio of air; 1.4 ambient; 1.36 within (and ideal case for) nozzle.
M Flight Mach (matches speed of aircraft).
M e Exhaust Mach upon leaving the nozzle.
v Speed of aircraft (flight speed/airspeed).
V e Exhaust speed upon leaving the nozzle.
A e Cross-sectional area of the end of the supersonic nozzle.
T e Exhaust temperature upon leaving the nozzle.
p a Ambient pressure (1 atmosphere at given altitude).
p e Exhaust pressure upon leaving the nozzle.
p 06 Maximum (stagnation) pressure generated by combustion.
p 0a Total (stagnation) pressure before combustion.
ma Mass flow rate of air only (in ramjet mode), and of exhaust only (in pulsejet mode).
F/m a Specific thrust. Special unit of measure: “(newton of thrust) per (kilogram per second of exhaust gas)”.
TSFC Specific fuel consumption. Special unit of measure: “(kilogram per second of fuel) per (newton of thrust)”.
[0054] Formulas Used in Calculations
[0055] 1. Regarding fuel-to-air ratio and exhaust temperature:
[0000] Assumptions:
[0000]
1. Within ramjet combustion, total pressure changes only once;
2. Pulsejet combustion occurs in a constant volume.
Formula for Ramjet Mode:
f =(( T 04 /T 0a )−1)/(( Q R /( c p *T 0a ))−( T 04 /T 0a ))
Formula for Pulsejet Mode:
f =(( T 04 /T 0a )−1)/(( Q R /( c v *T 0a ))−( T 04 /T 0a ))
2. Regarding Exhaust Mach:
M e 2 =(2/( H R −1))*((1+(( H R −1)/2)* M 2 )*(((p 06 /p 0a )*( p a /p e )) (H R −1)/H R −1))
3. Regarding Exhaust Speed:
v e =M e *(( H R *R*T 04 )/(1+( Me 2 *(( H R −1)/2)))) 0.5
4. Regarding Specific Thrust:
Gross (Ignoring Speed of Aircraft):
F/m a =( v e *(1+ f ))+(A e *( p e −p a )/ m a )
Net (Accounting for Speed of Aircraft):
F/m a =( v e *(1+ f ))− v +( A e *( p e −p a )/ m a )
5. regarding specific fuel consumption:
TSFC=f /( F/m a )
Pulsejet Mode Behavior at Take-off:
Environment: T a =290 K, p a =101325 P a , T 04 =2000 K, air density=1.225 kg/m 3 .
Before first pulse: p 02 =p a , T 02 =T a (no speed yet).
On first pulse:
Combustion (from formula 1): f=0.028
Assuming perfect gas behavior: (p 06 /p 0a )=(T 06 /T 0a ), so p 06 =698793.1 Pa
To avoid shock formation at exhaust, exhaust pressure must (ideal case) equal ambient pressure, so:
Exhaust Mach (from formula 2): M e =1.9253
Exhaust speed (from formula 3): v e =1317.43 m/s
Gross specific thrust (from formula 4): F/m a =1354.32 N/(kg/s)
Specific fuel consumption (from formula 5): TSFC=2.067*10 −5 (kg/s)/N
Comparison: Typical turbojet TSFC at take-off is 7*10 −5 (kg/s)/N and typical high bypass turbofan TSFC at take-off is 1.5*10 −5 (kg/s)/N.
Estimating main burner dimensions for 1 MN (same as 224719 LBS) thrust at 200 pulses/second at take-off:
Exhaust m a =Thrust/(F/m a) =738.38 kg/s, therefore 3.69 kg of exhaust are required from each pulse.
Only the air which is initially enclosed in the main burner at environment air density is exhausted in each pulse, so the main burner required volume is 3.013 m 3 ; if choosing a main burner length of 2 m, then the internal cross-sectional area is 1.5065 m 2 , so the main burner internal radius is 0.7 m.
Pulsejet Mode Behavior at Mach 2:
Environment (from Reference 1, appendix III):
Altitude=10 km (given), v=599.064 m/s (derived),
T a =223.252 K, p a =26500 Pa, T 04 =2000 K, air density=0.41351 kg/m 3 .
Before the air enters main burner (from Reference 2, table A2):
p 0a =207355.2426 Pa
Due to a slight-vacuum effect created by each pulse plus airflow buildup on the front flow gate (when closed), the maximum possible pressure before combustion is 2* p 0a =414710.4852 Pa, but total temperature stays constant (401.85 K).
Combustion from formula 1): f=3.154*10 −4
Assuming perfect gas behavior: (p 06 /P 0a )=(T 06 /T 0a ), so p 06 =2064006.39 Pa
To avoid shock formation at exhaust, exhaust pressure must (ideal case) equal ambient pressure, so:
Exhaust Mach (from formula 2): M e =3.4642
Exhaust speed (from formula 3): v e =1721.775 m/s
Net specific thrust from formula 4): F/m a =1123.25405 N/(kg/s)
Specific fuel consumption from formula 5): TSFC=2.808*10 −7 (kg/s)/N
Comparison: The most efficient turbofans to date, used on aircraft Boeing 777™, have a TSFC of 10 −6 (kg/s)/N.
Ramjet Mode Behavior at Mach 2:
Environment: Altitude=10 km (given), v=599.064 m/s (derived), T a =223.252 K,
p a =26500 P a ,
T 04 =2500 K, air density=0.41351 kg/m 3 .
Within One Small Combustor:
Before air entry:
p 0a =207355.2426 Pa and T 0a =401.85 K
Combustion (from formula 1): f= 0 . 04955
Assuming perfect gas behavior: (p 06 /p 0a )=(T 06 /T 00a ), SO p 06 =2064006.39 Pa
To ensure that the air coming into the main burner does not change direction and/or speed upon mixing with the exhaust from the small combustors (herein described as the ramjet burners 116 ), the exhaust speed from the small combustors must equal the speed of the main burner airflow:
v e(combustor) =599.064 m/s. This leaves a lot of high pressure and temperature (from the small combustors' exhaust) to mix with (thus increasing the overall pressure and temperature of) the airflow in the main burner, so:
Exhaust Mach (from formula 2): M e(combustor) =0.6276
Exhaust pressure (from Reference 2, table A2): p e(combustor) =1582881.547 Pa
Exhaust temperature (from Reference 2, table A2): T e(combustor) =2317.44 K
Within Main Burner Combustion Occurs in Small Combustors Only):
Assumption: Total projected area of all small combustors is 20% of main burner cross-sectional area, therefore airflow behavior resembles that of a “turbofan with bypass ratio of 4 and mixed airflows”, so:
Mean pressure (not stagnation) in main burner becomes 337776.31 Pa
Mean temperature (not stagnation) in main burner becomes 642.09 K
Speed of sound in main burner from formula 3) is 507.93 m/s and Mach of mixed airflow is 1.1794 upon completing the mixing process, so from Reference 2, table A2: p 0(exit) =798090.605 Pa and T 0(exit) =820.9 K. Now exit pressure must match ambient pressure, so p(exit)/p 0 (exit)=0.332, so:
Exhaust Mach (from formula 2): M e =1.365
Exhaust temperature (from Reference 2, table A2): T e =598.04207 K
Exhaust speed (from formula 3): v e =659.5 m/s
Net specific thrust (from formula 4): F/m a =665.5307 N/(kg/s)
Specific fuel consumption ( from formula 5): TSFC=1.489*10 −5 (kg/s)/N
Given the previously estimated dimensions, thrust in ramjet mode at Mach 2 is 248368 N (same as 55813 LBS).
Comparison: At Mach 2 flight speed, existing ramjets have an average TSFC of 6*10 −5 (kg/s)/N and turbojets have an average TSFC of 3.5*10 −5 (kg/s)/N.
Ramjet Mode Behavior at Mach 6:
Environment: Altitude=10 km (given), v=1797.192 m/s (derived),
T a =223.252 K, p a =26500 P a ,
T 04 =2500 K, air density=0.41351 kg/m 3 .
Within One Small Combustor:
Before air entry (from Reference 2, table A2):
p 0a =4184139 Pa and T 0a =1912.685 K
Combustion (from formula 1): f=0.01387
Assuming perfect gas behavior: (p 06 /p 0a )=(T 06 /T 0a ), so p 06 =54719071.62 Pa
To ensure that the air coming into the main burner does not change direction and/or speed upon mixing with the exhaust from the small combustors, the exhaust speed from the small combustors must equal the speed of the main burner airflow:
V e(combustor) =1797.192 m/s. This leaves a lot of high pressure and temperature (from the small combustors' exhaust) to mix with (thus increasing the overall pressure and temperature of) the airflow in the main burner, so:
Exhaust Mach (from formula 2): M e(combustor) =2.86
Exhaust pressure (from Reference 2, table A2): p e(combustor) =18402023.8 Pa
Exhaust temperature (from Reference 2, table A2): T e(combustor) =948.425 K
Within Main Burner (Combustion Occurs in Small Combustors Only):
Assumption: Total projected area of all small combustors is 20% of main burner cross-sectional area, therefore airflow behavior resembles that of a “turbofan with bypass ratio of 4 and mixed airflows”, so:
Mean pressure (not stagnation) in main burner becomes 3701604.76 Pa
Mean temperature (not stagnation) in main burner becomes 368.3 K
Speed of sound in main burner (from formula 3) is 379.15 m/s and Mach of mixed airflow is 4.74 upon completing the mixing process, so from Reference 2, table A2: p 0(exit) =143473052.7 Pa and T 0(exit) =2022.85 K. Now exit pressure must match ambient pressure, so p (exit) /p 0(exit) =1.847*10 (−4) , so:
Exhaust Mach (from formula 2): M e =7.4
Exhaust temperature (from Reference 2, table A2): T e =1710.077 K
Exhaust speed (from formula 3): v e =6045.747 m/s
Net specific thrust (from formula 4): F/m a =6062.518 N/(kg/s)
Specific fuel consumption (from formula 5): TSFC=4.5756*10 −7 (kg/s)/N
Given the previously estimated dimensions, thrust in ramjet mode at Mach 6 is 6787387.9 N (same as 1525255.7 LBS).
Comparison: At Mach 6 flight speed, existing ramjets have an average TSFC of 2.5*10 31 5 (kg/s)/N.
[0130] The following two references were referred to in working out the above:
1. P. Hill, C. Peterson: Mechanics and Thermodynamics of Propulsion, 2nd edition Addison-Wesley Publishing Company, 1992 ISBN 0-201-146592 2. M. Saad: Compressible Fluid Flow Prentice Hall, Inc., 1985 ISBN 0-13-163486
[0133] In the preceding detailed description, reference has been made to the accompanying drawings that form a part hereof, and in which are shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments, and certain variants thereof, have been described in sufficient detail to enable those skilled in the art to practice the invention. It is to be understood that other suitable embodiments may be utilized and that logical changes may be made without departing from the spirit or scope of the invention. The description may omit certain information known to those skilled in the art. The preceding detailed description is, therefore, not intended to be limited to the specific forms set forth herein, but on the contrary, it is intended to cover such alternatives, modifications, and equivalents, as can be reasonably included within the spirit and scope of the appended claims. | The present invention provides a hypersonic jet engine able to start in air-breathing mode, on its own, from zero speed without a compressor. The hypersonic jet engine, known herein as the hyperjet is also able to fly an aircraft at and faster than Mach 6 without using the scramjet method of combustion, while maintaining a fuel economy superior to that of a aircraft utilizing a turbofan engine. The present invention is operable in a pulsejet mode, a ramjet mode, and chemical rocket mode, and utilizes front and back airflow gates driven by DC motors or electromagnetic fields. | 5 |
FIELD OF THE INVENTION
This invention relates to a laser device, and, more particularly, relates to enhancing laser device performance by heating a mirror of the laser device.
BACKGROUND OF THE INVENTION
Laser devices are now well known, and it is likewise well known to provide a mirror at one, or both, of the opposite ends of the laser tube. It is likewise now well known that such a mirror may be formed by a substrate having a reflective coating thereon, which coating can be formed by applying a plurality of layers of dielectric material to form the reflective coating.
The development of thin-film dielectric coating technology has advanced enormously since the inception of the laser, and, in essence, the laser became practical only after mirrors of very high reflectivity could be manufactured. The layers of film forming the reflective coating are normally vacuum deposited onto polished glass mirror blanks as alternating layers of high and low refractive index materials (usually refractory oxides) designed to generate enhanced reflectance at the selected laser wavelength via constructive interference. In general, the higher the spectral reflectance and the lower all other losses (i.e. diffused scatter, transmission, and absorption), the higher the mirror quality.
It is likewise now well known that heat can be applied to a lens arrangement or the like, including application of heat to a coating on the lens, but such heating has commonly heretofore been utilized to prevent fogging and the like (see, for example, U.S. Pat. Nos. 3,495,259, 4,355,861, 1,791,254, 2,442,913 and 2,376,710).
SUMMARY OF THE INVENTION
This invention provides mirror heating for the purpose of enhancing performance of a laser device by minimizing losses from induced light absorption due to color-centers in the reflective coating of the mirror.
It is an object of this invention to provide an improved laser device and method providing mirror heating.
It is another object of this invention to provide an improved laser device and method providing mirror heating to minimize losses from induced light absorption due to color-centers in the reflective coating of the mirror.
It is another object of this invention to provide an improved laser device and method that includes mirror heating to reverse F-center formation in refractive index materials forming a reflective coating on the substrate of a mirror.
It is still another object of this invention to provide a heating system for a laser device having a mirror one portion of which is susceptible to induced light absorption.
With these and other objects in view, which will become apparent to one skilled in the art as the description proceeds, this invention resides in the novel construction, combination, arrangement of parts and method substantially as hereinafter described, and more particularly defined by the appended claims, it being understood that changes in the precise embodiment of the herein disclosed invention are meant to be included as come within the scope of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings illustrate complete embodiments of the invention according to the best mode so far devised for the practical application of the principles thereof, and in which:
FIG. 1 is an illustration of a pure ionically bonded crystal with a lattice vacancy shown at positive and negative ion sites and at a coupled pair of vacant sites of opposite sign;
FIG. 2 is an illustration of Schottky and Frenkel defects in an ionic crystal with arrows being provided to indicate displacement of the ions (in a Schottky defect, the ion is shown to move to the surface of the crystal, and, in a Frenkel defect, the ion is shown to move to an interstitial position);
FIG. 3 is an illustrative diagram of a formed F-center;
FIG. 4 is a simplified side view illustration of an HE-NE laser device having mirrors at the opposite ends of the laser tube;
FIG. 5 is a partial simplified side view illustration of the cathode end of the laser device shown in FIG. 4 and illustratin one embodiment of the heating system of this invention incorporated therein;
FIG. 6 is a partial side view illustration of the anode end of the laser device shown in FIG. 4 and illustrating a second embodiment of the heating system of this invention incorporated therein;
FIG. 7 is an end view of the anode end of the laser device as shown in FIG. 6; and
FIG. 8 is a simplified electrical diagram illustrating connection of the power supply to the laser device and heating system.
DESCRIPTION OF THE INVENTION
One of the primary goals of material science is generally to provide a perfect material, and a perfect crystal, for example, is the ultimate in material perfection. Thin film optical coatings, however, are an area of material science wherein the very nature of the manufacturing process precludes perfection, since said coatings are inherently amorphous.
The process of forming such a material generally starts with as pure a material (and thus generally crystalline) as can be practically procured, and this material is then evaporated in a vacuum chamber where the material is deposited onto a substrate (in this case a mirror substrate), generally at an elevated temperature.
By alternately using high and low refractive index materials having a one-fourth wavelength optical thickness, a transparent glass blank can be transformed into a highly reflective mirror that is selectively reflective at the tuned wavelength (where the one-fourth wavelength is exactly periodic) and is relatively transmissive at other wavelengths. These films are generally amorphous (i.e. non-crystalline), and are invariably less perfect than the crystalline material from which they had been evaporated.
Any deviation in the crystal from a perfect periodic lattice or structure is an imperfection, with the common point imperfections being chemical impurities, vacant lattice sites, and extra atoms not in regular lattice positions. Line imperfections are called dislocations, and a crystal surface is a planar imperfection, with its surface electron and phonon states.
Crystals are, therefore, always imperfect in some respect unless infinite in extent. The nature of the common imperfections are fairly well understood for most solids, and much work has been heretofore accomplished concerned with the alkali and silver halides important to photographic processes, germanium and silicon as they relate to semiconductors, and copper and alloys in general. In fact, an alloy may represent a high concentration of point imperfections.
Many important properties are controlled as much by imperfections as by the nature of the host crystal, which may act only as a vehicle or solvent or matrix for the imperfections. The conductivity of some semiconductors, for example, is due entirely to trace amount of chemical impurities, the color of many crystals arises from imperfections, and the luminescence of crystals is nearly always connected with the presence of impurities. Also, diffusions of atoms may be accelerated enormously by impurities or imperfections, and mechanical and plastic properties are usually controlled by imperfections.
If thin films could be deposited to grow nearly perfect crystalline layers, these layers would have ideal optical properties. However, since mirror coatings involve many alternating layers of different materials, there is always strong dislocations between layers, and these boundaries are sources of increased diffuse scattering loss. Furthermore, it is difficult to grow useful crystalline layers in vacuum. The choice has therefore been to move away from crystalline states toward totally amorphous states, and in thin-film optical coatings, the most desirable film structure utilized today is amorphous.
Amorphous films can be grown more readily than can crystalline films. However, in most cases, films possess some internal crystallites which are generally deleterious to optical performance since a mixture of amorphous and crystalline states results in undesirable high diffuse scattering. Diffuse scatter and particle generated point-defects are the predominant sources of scattering losses found in coated mirrors.
In summary, in the absence of being able to produce consistent crystalline layers, it has been found to be more productive to stay completely away from crystalline films.
As brought out above, a limiting loss mechanism is absorption, and this can occur by a variety of means. While absorption is a greater problem in amorphous states than crystal states, the mechanisms are the same. To understand the mechanism in thin films, it is useful to examine the same phenomenon in simple ionic crystals. Obviously, absorbing impurities come to mind, however, other subtle forms of induced light absorption can occur.
In a crystal, such absorption can occur when there is a lattice vacancy or interstitial void. The simplest imperfection is a lattice vacancy, which is a missing atom or ion, also known as a Schottky defect. A lattice vacancy is often indicated in illustrations and in chemical modeling by a square, in the manner as is indicated in FIG. 1. A Schottky defect can be created in a perfect crystal by transferring an atom from a lattice site in the interior to a lattice site on the surface of the crystal, as indicated in FIG. 2.
In thermal equilibrium in an otherwise perfect crystal, a certain number of lattice vacancies are always present, because the entropy is increased by the presence of disorder in the structure. In metals with close-packed structures, the proportion of lattice sites vacant at temperatures just below the melting point is of the order of 10 -3 to 10 -4 . But in some alloys, in particular, the very hard transition metal carides such as TiC, the proportion of vacant sites of one component can be as high as 50%.
Another vacancy defect is the Frenkel defect, as is also indicated in FIG. 2, in which an atom is transferred from a lattice site to an interstitial position, a position that is not normally occupied by an atom.
The presence of a lattice defect often leads to absorption, and a color center is a lattice defect that absorbs visible light. While an ordinary lattice vacancy does not color crystals, it does affect absorption in the ultraviolet (UV) range. The simplest color center is an F-center, which is named from the German word for color (Farbe).
F-centers can be produced in thin films by ultraviolet radiation, and an F-center is often identified by electron spin resonance as an electron bound at a negative ion vacancy, as indicated in FIG. 3. If the valence electron of the metal atom is not bound tightly to the atom, the electron migrates in the crystal and becomes bound to a vacant negative ion site. A negative ion vacancy in an otherwise perfect periodic lattice has the effect of an isolated positive charge in that it attracts and binds an electron.
The F-center is the simplest trapped electron center in crystals. The optical absorption of an F-center arises from an electric dipole transition to a bound excited state of the center. As is indicated in FIG. 3, an F-center is a negative ion vacancy with one excess electron bound at the vacancy. The distribution of the excess electron is largely on the positive metal ions adjacent to the vacant lattice site. These and other centers are usually identified by their optical properties.
Holes may also be trapped to form color centers. Hole centers differ, however, from electron centers in that a hole in the last orbital shell of an ion leaves it in a lower electronic configuration, whereas an electron added to the filled shell leaves the ion in a higher electronic configuration. The chemistry of the two configurations is different. The antimorph to the F-center is a hole trapped at a positive ion vacancy, but no such center has been successively identified to date.
The primary difference between thin-film materials and the ionic crystals above discussed is that the materials used are generally covalently bonded rather than ionically bonded. Also, the amorphous films can be best considered as material matrices rather than crystalline lattices. Most of the materials are transition metal oxides (refractory oxides) which are ordinarily transparent in the visible light range. Commonly used refractory oxide materials are S i O 2 , T i O 2 , HfO 2 , Ta 2 O 5 , and ZrO 2 . These materials characteristically form F-centers when exposed to ultraviolet light, inducing absorption.
When these materials are used in manufacturing of laser mirrors, the mirrors are most often sealed to the plasma discharge and exposed to rich ultraviolet light. Their performance is degraded with time and ultraviolet dosage, and the primary result of this induced absorption is reduction in laser output power.
Summarizing, the F-center is characterized by a trapped "free" electron which is ordinarily created by ultraviolet broken bonds local to the F-center. The "free" electron migrates to the F-center where it is trapped. The reduction of these trapped electrons and destruction of the absorbing electrons is thus of great importance to the longevity and enhancement of laser mirror coatings.
In this invention, a system and method are disclosed for increasing longevity of a laser by using a heater to heat the mirror, or mirrors. The mechanism by which the heater eliminates, or destroys, F-centers is primarily the result of thermal energy being added to the site and raising the "free" electron to an energy level where it can migrate back to a stable preferred site. It has been verified by our experiments, that temperatures in the range of 50° C. to 100° C. are typically sufficient to reverse F-center formation in most investigated materials. With the advent of hard sealed (glass-to-metal) mirrors, operation of mirrors at such temperatures is entirely feasible since processing steps require temperatures of about 450° C. for mirror sealing.
A typical laser construction is illustrated in FIG. 4. As shown, HE-NE laser device 9 conventionally includes a glass capillary tube 11 having a metal cathode 13 and a glass end wall 15 therearound. A glass-to-metal seal 16 is provided between the glass end wall and the metal cathode, as indicated in FIG. 4.
At the cathode end of the laser device, a metal cathode end section 17 with mirror retainer 18 is provided for connection of the cathode to the negative side of a power supply and for positioning mirror 19 adjacent to the end of, and in alignment with, discharge capillary bore 21 of section 17, which bore is also aligned with capillary tube 11. As is conventional, mirror 19 is formed utilizing a substrate 23 (normally a glass substrate) having a coating 25 thereon normally formed by layers of reflective material as above described. A glass-to-metal hard seal 26 is provided between substrate 23 and mirror retainer 18.
A metal anode 27 is positioned adjacent to capillary tube 11 at the end opposite to that of cathode 9. Anode 27 provides for connection of the positive side of the power supply to the laser tube and has a discharge capillary bore 29 therein aligned with capillary tube 11. Mirror 31 is received at mirror retainer 32 at the end of anode 27 and is aligned with bore 29 and capillary tube 11. Mirror 31 includes a substrate 33 (also normally a glass substrate) having a coating 35 thereon normally formed by layers of reflective materials as above described. A glass-to-metal hard seal 36 is provided between substrate 33 and mirror retainer 32.
Embodiment 39 of the heating system of this invention is shown in FIG. 5 positioned to heat mirror 19. Heater coil 41 is a length of wire coiled around a form (not shown) and pressed into cylindrical cup 43 with the cup being positioned around mirror cup 44. Mirror cup 44 is configured to retain and position mirror 19 within and surrounded by heater coil 41 so that when the heater coil is energized, heat is provided to the mirror.
A second embodiment 45 of this invention is shown in FIGS. 6 and 7 positioned to heat mirror 31. As shown, a cylindrical resistor potting form, or mandrel, 47 has a plurality of resistors 49 (typically 8 resistors for providing uniform heat distribution, as illustrated in FIG. 7) embedded therein with the resistors being connected in series with one another by leads 51 (as also indicated in FIG. 7). As best indicated in FIG. 6, mandrel 47 is positioned around mirror cup 53 of anode 27. Mirror cup 53 is configured to retain and position mirror 31 within and surrounded by mandrel 47 so that when current is passed through the resistors, heat is provided to the mirror.
While not specifically illustrated, it is to be understood that heating, or thermal energy processing, systems 39 and 45, as illustrated in FIGS. 5 through 7, could be utilized to heat, or provide thermal energy to, a mirror positioned at either the anode or cathode of the laser tube and the invention is not meant to be limited to the illustrated use as specifically shown in FIGS. 5 through 7.
As indicated in FIG. 8, a conventional power supply 57 can be utilized to energize the laser device with the negative side 59 of the power supply being connected with cathode 13 (while indicated in FIG. 8 and connected generally to the cathode end of the laser, lead 59 can be connected to cathode end section 17), and the positive side 61 being connected with anode 27.
When embodiment 45 (as shown in FIGS. 6 and 7) of the heater system is utilized, the resistors 49 forming the heating element can also be the ballast resistance (indicated generally by the numeral 63 in FIG. 8), which ballast resistance is necessary for operation of the laser device. In this embodiment, the ballast resistance thus serves as the heating system and is energized through power supply 57 to thus provide heat to the associated mirror.
When embodiment 39 (as shown in FIG. 5) of the heating system is utilized, then a conventional low voltage power supply 65 is utilized and leads 67 are connected to opposite sides of heater coil 41 for energization of the heater coil to cause heat to be produced and supplied to the associated mirror.
Regardless of which embodiment of the heating system is utilized, it has been found that sufficient heat can be generated at the reflective mirror, by the heating system of this invention, to reverse F-center formation. Tests have indicated that lasers having highly sensitive laser lines (such as, for example, HE-NE lasers operating at 543 nm, 594 nm, and 612 nm), that heretofore ceased operation in less than 100 hours, can be enhanced to last indefinitely (over several thousand hours) by adding mirror heating according to this invention, which heating is preferably applied to the associated mirror during the entire time during which the laser device is in operation.
From the foregoing, it should be appreciated that understanding and defeating F-center mechanisms in laser mirror coatings utilizing this invention has allowed creation of laser products with longevity far exceeding those heretofore possible. | A laser device is disclosed having mirror heating to enhance performance of the device by minimizing induced light absorption to thereby improve mirror quality. The mirrors of a laser device are commonly made of a substrate having a coating thereon formed by alternating layers of high and low refractive index materials, normally classified as refractory oxide materials, which materials are susceptible to formation therein of color centers, such as formation of F-centers when exposed to ultraviolet light, which color centers reduce mirror quality due to induced light absorption losses. By heating the mirror, the F-centers are substantially eliminated to thereby improve mirror quality and enhance the longevity of the laser device. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a video monitor system having at least a video signal source and at least a monitor for providing a video image from the video signal source on the monitor and particularly relates to a video monitor system at least a video camera and at least a monitor for providing a video image from the video camera on the monitor.
2. Description of the Prior Art
A video monitor system having a plurality of video cameras for generating a plurality of video signals, a coaxial cable, a plurality of modulators for modulating the video signals to provide respective fixed channels of video signals and combining units for multiplexing a plurality of video signals on the coaxial cable, a plurality of distributors and demodulators for selectively receiving video signals respectively, a plurality of television monitors for displaying the received video signals respectively is known.
FIG. 15 is a block diagram of a prior art video monitor system disclosed in Japanese patent application provisional publication No. 5-7330. This prior art video monitor system comprises a coaxial cable 1501 for transmitting multiplexed video signals, a plurality of cameras 1502-1 to 1502-10 for generating video signals respectively, modulators 1503-1 to 1503-10 for modulating a the video signals having fixed frequencies respectively, combining units (combiners) 1504- to 1504-10 for multiplexing the modulated video signals on the coaxial cable 1501, distributors 1507-1 to 1507-4 for distributing the multiplexed video signals, demodulators for selectively demodulating the multiplexed video signals having predetermined frequencies respectively, and video monitors 1505-1 to 1505-4 for displaying the video signals respectively.
In this system, the modulators 1503-1 to 1503-10 modulate video signals supplied from the video cameras 1502-1 to 1502-10 at predetermined different frequencies. The combining units 1504-1 to 1504 10 multiplex the modulated video signals on the coaxial cable 1501. On the monitor side, the distributors 1507-1 to 1507-4 distributes the multiplexed video signals respectively. The demodulator selectively demodulate the multiplexed video signals with different predetermined frequencies respectively. The video monitors 1505-1 to 1505-4 display the video signals to reproduce different images respectively.
An operator can selectively display an image from either of video cameras 1502-1 to 1502-10 on each video monitor by controlling the demodulation frequency.
SUMMARY OF THE INVENTION
The aim of the present invention is to provide an improved video monitor system.
According to this invention, a first video monitor system is provided which comprises: a transmitting medium, having L channels of L video signals, for transmitting the L video signals and data; a video signal source portion including; M video signal source units, each of the M video signal source units receiving the data from the transmission medium and selectively generating and supplying one of the L video signals to the transmission medium through one of the L channels in accordance with the data; a monitor portion including; N monitor units, each of the N monitor units receiving the data from the transmission medium and selectively receiving and reproducing one of the L video signals from one of the L channels in accordance with the data, the L, M, and N being natural numbers more than one; a monitor control portion including; a plurality of monitor control terminals, each of the monitor control terminals in response to a request, generating and transmitting the data indicating which one of the M video signal sources is requested to be operated and the data indicating which one of the N monitor units is requested to be operated to the transmitting medium; and a control portion including: a receiving circuit for receiving the data from the monitor control portion via the transmission medium; a channel condition detection portion responsive to the data indicating which one of the M video signal sources is requested to be operated and the data indicating which one of the N monitor units is requested to be operated for detecting a condition of the L channels; a determining portion responsive to the channel condition detection portion for determining which one of the L channels is used in accordance with the detected condition of the L channels; an operating portion, responsive to the data indicating which one of the M video signal sources is requested to be operated and the data indicating which one of the N monitor units is requested to be operated, for operating one of M video signal sources indicated by the data from the monitor control terminal portion to supply one of L video signals using the determined one of L channels and operating one of the N monitor units indicated by the data from the monitor control terminal portion to receive and reproduce one of L video signals from the determined one of L channels through generating and transmitting the data to the transmitting medium.
In the first video monitor system, the M video source units, the N monitor units, and the monitor control terminals may have addresses respectively and the control portion transmits the data directed to the more than one of the addresses at once.
The first video monitor system may further comprise a synchronizing signal generation circuit for generating a synchronizing signal, wherein the transmitting medium further transmits the synchronizing signal and the M video source units and N monitor units further comprise synchronizing signal receiving circuits respectively, each of the M video signal source units selectively generates and supplies one of the L video signals to the transmission medium in response to the synchronizing signal from the synchronizing receiving circuit, and each of the N monitor units selectively receives one of the L video signals in response to the synchronizing signal from the synchronizing receiving circuit thereof.
In the first video monitor system, each of the monitor control terminals may further comprise first generating and transmitting portion responsive to a acquiring request for generating the data indicative of acquiring a right of controlling a desired one of the M video signal sources to the control portion and second generating and transmitting portion responsive to a releasing request for generating the data indicative of releasing the right of controlling the desired one of the M video signal sources to the control portion, the control portion further includes a priority data storing portion for storing priority data of the M video signal sources and a judging portion for, when the receiving circuit of the control portion receives the data indicative of acquiring the right of controlling the desired one of the M video signal sources from one of the N monitor terminal in the case that the receiving circuit of the control portion has received the data indicative of acquiring the right of controlling the desired one of the M video signal sources from another one of the N monitor control terminals and has not received the data indicative of releasing the right from another one of the N monitor control terminal, judging which one of one or the another one of the N monitor control terminals has a higher priority in accordance with the priority data, and transmits the data indicative of providing the right of controlling the desired one of the M video signal sources to either one of the N monitor control terminals which has been judged to have the higher priority.
The first video monitor system may further comprises a recording portion for receiving the data from the generating portion through transmission medium and selectively receiving and recording one of the L video signals using one of the L channels in accordance with the data, wherein the control portion may further comprise a recording operation portion responsive to data indicative of the recording request and the determining portion for operating one of the M video signal sources using the determined one of the L channel in accordance with the data indicative of the recording request. In this case, it further comprises a synchronizing signal generation circuit for generating a synchronizing signal, wherein the transmitting medium transmits the synchronizing signal and the recording portion has a synchronizing signal receiving circuit for receiving the synchronizing signal and the recording portion recording the received one of the L video signal in response to the synchronizing signal from the synchronizing signal receiving portion.
In the first video monitor system, the L<M.
In the first video monitor system,the L<N.
In a second video monitor system, the M video signal sources in the first video monitor system comprises video camera for taking a picture and generating the video signal in accordance with a picture and the other structure is the same as the first video monitor system.
In the second video monitor system, the control portion may further comprise a generating portion response to a response request command for generating the data indicative of the response requesting command, the transmitting portion transmits the data indicative of the response requesting command to at least one of the M video signal sources and the N monitor terminals and the at least one of the M video signal sources and the N monitor terminals receives the data indicative of the response requesting command and generates and transmits the data indicative of the response responsive to the response requesting command to the control portion, and the control portion further comprises a judging portion for judging a condition of the transmitting medium from the data indicative of the response received by the receiving circuit.
In the second video monitor system, the M video sources and the N monitor units may have addresses respectively and the control portion further includes an address storing portion for storing address data of the M video sources and the N monitor units, the at least one of the M video signal sources and the N monitor terminals receiving the data indicative of the response requesting command generates and transmits the data indicative of a response to the response requesting command with information of the address thereof to the control portion, and the judging portion further includes a detection portion for detecting a location of a defect in the transmitting medium from the address data in the address data storing portion and the information of the address in the data which could be received by the receiving circuit.
In the second video monitor system, each of M video signal sources further comprises an alarm signal detection portion for detecting an alarm signal and for generating and transmitting the data indicative of the alarm signal, the control portion further includes an alarm operation portion for executing a predetermined alarm operation in a first condition of the M video signal sources and the N monitor units in response to the data indicative of the alarm signal, a timer circuit for detecting a timing when a preset time has come, a timer operation portion for executing a predetermined timer operation in a second condition of the M video signal sources and the N monitor units in response to the timer operation portion, a condition detection and storing portion responsive to the data indicative of the alarm signal and the timer portion for detecting a condition of the M video signal sources and the N monitor units and for storing data of the condition, a completion detection portion for detecting completion of the alarm operation and predetermined timer operation, and a restoring portion responsive to the completion detection portion for operating the video signal source portion and the monitor portion in accordance with the data of the detected condition.
In the second video monitor system, the control portion further includes a sequence control portion responsive to a sequence operation request for generating and transmitting the data indicative of a sequence of operations of more than one of the M video signal sources to the more than one of the M video signal sources respectively and the N monitor units and a start timing generation portion responsive to a sequence operation start command for generating the data indicative of a start timing, and the each of M video signal sources and the N monitor units further comprises a sequence storing portion for storing the data indicative of the sequence, and the more than one of M video signal sources and the N monitor units which have received the data indicative of the sequence execute the sequence of operations when they receive the data indicative of start timing. In this case, this second video monitor system may further comprise a synchronizing signal generation circuit for generating a synchronizing signal, wherein the transmitting medium transmits the synchronizing signal and the M video source units and N monitor units have synchronizing signal receiving circuits respectively, and the more than one of M video signal sources and the N monitor units which have received the data indicative of the sequence execute the sequence of operations in response to the received synchronizing signal.
In the second video monitor system, the control portion further includes a conditional data storing portion for storing predetermined conditional data, a condition detection and storing portion responsive to a mode change command for detecting a condition of the M video signal sources and the N monitor units and storing data of the detected condition, a mode changing portion responsive to the detection portion for operating the video signal source portion and the monitor portion in accordance with predetermined conditional data, and a restoring portion responsive to a mode restoring command for operating the video signal source portion and the monitor portion in accordance with the data of the detected condition. In this case, the each of M video signal source units includes an alarm signal detection portion for detecting an alarm signal and transmitting the data indicative of detecting the alarm signal and the receiving circuit generates the mode change command when the data indicative of detecting an alarm signal. Similarly, in this case, the control portion further includes a timer circuit for detecting a timing when a preset time has come and the control portion generates the mode change command when the timer circuit detects the timing.
According to this invention a third video monitor system which comprises: a plurality of networks, each comprising: a transmitting medium, having L channels for transmitting L video signals, for transmitting data; a video signal source portion including; M video signal source units, each of the video signal source units receiving the data from the transmission medium and selectively generating and supplying one of the L video signals to the transmission medium using one of the L channels in accordance with the data; a monitor portion including; N monitor units, each of the monitor units receiving the data from the transmission medium and selectively receiving and reproducing one of the L video signals from one of the L channels in accordance with the data, the L, M, and N being natural numbers more than one; a monitor control portion including; a plurality of monitor control terminals, each of the monitor control terminals in response to a request, generating and transmitting the data indicating which one of the M video signal sources is requested to be operated and which one of the N monitor units is requested to be operated to the transmitting medium; and a control portion including: a receiving circuit for receiving the data from the monitor control portion via the transmission medium; a channel control portion for detecting used and unused conditions of the L channels and storing the channel control data; a determining portion for determining which one of the L channels is used in accordance with the channel control data in response to the data from the monitor control portion via the receiving circuit; an operating portion, responsive to the data indicating which one of the M video signal sources is requested to be operated and the data indicating which one of the N monitor units is requested to be operated, for operating one of M video signal sources indicated by the data from the monitor control terminal portion to supply one of L video signals using the determined one of L channels and operating one of the N monitor units indicated by the data from the monitor control terminal portion to receive and reproduce one of L video signals from the determined one of L channels through is generating and transmitting the data to the transmitting medium; a center monitor control terminal, communicating with the control portions of the plurality of networks, for, in response to a monitoring request, determining which one of the plurality of networks is requested in accordance with the monitoring request, generating and transmitting the data indicating which one of the M video signal sources of the determined network is requested to be operated to the control portion of the determined network; and a switching portion, connected to the transmitting mediums of the plurality of networks, for selectively supplying one of the M video signals corresponding to the monitoring request from the determined network; and at least a center monitor unit for reproducing one of video signals from the switching portion.
BRIEF DESCRIPTION OF THE DRAWINGS
The object and features of the present invention will become more readily apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a block diagram of a video monitor system of the first to fourth embodiments;
FIG. 2 is a block diagram of the sever computer in FIG. 1 of the first embodiment;
FIG. 3 is a block diagram of the monitor operation terminal computer in FIG. 1 of the embodiments of this invention;
FIG. 4 is a block diagram of a set of camera including a camera, a camera RF modem, and a bi-directional separator in FIG. 1 of embodiments of this invention;
FIG. 5 is a block diagram of a set of monitor including a monitor, a monitor RF modem, and a bi-directional separator in FIG. 1 of embodiments of this invention;
FIG. 6A is a block diagram of a set of a monitor operation terminal including a monitor operation terminal, a control signal RF modem, and a bi-directional separator in FIG. 1 of embodiments of this invention;
FIG. 6B is a block diagram of a set of a server including the server computer, a control signal RF modem, and a bi-directional separator in FIG. 1 of embodiments of this invention;
FIG. 7 is a block diagram of the server computer of the second embodiment;
FIG. 8 is a block diagram of an example of a video monitor system of the second embodiment indicating the trouble portion;
FIG. 9 is a diagram of an address table of the second embodiment shown in FIG. 7;
FIG. 10 is a block diagram of the server computer of the third embodiment;
FIG. 11 is a block diagram of a server computer of the fourth embodiment;
FIG. 12 is a block diagram of a set of VTR portion in FIG. 1 of this invention;
FIG. 13 is a block diagram of a video monitor system of the fifth embodiment;
FIG. 14 is a block diagram of a set of center monitor of fifth embodiment;
FIG. 15 is a block diagram of a prior art video monitor system;
FIG. 16 is a diagram of a flow chart of monitor acquiring program of the embodiments of this invention;
FIG. 17 is a diagram of a flow chart of the connection control program in FIG. 2;
FIG. 18 is a diagram of a flow chart of the camera control program in FIG. 2;
FIG. 19 is a drawing of a flow chart of a right of control acquiring program of the first embodiment;
FIG. 20 is a drawing of a flow chart of the priority control program in the server computer of the first embodiment;
FIG. 21 is a diagram of a flow chart of the system control program of the second embodiment shown in FIG. 7
FIG. 22 is a diagram of a flow chart of the system control program of the second embodiment shown in FIG. 7;
FIG. 23 is a diagram of a flow chart of the alarm operation control program in the server computer of a third embodiment
FIGS. 24A and 24B are diagrams of flow charts of the third embodiment;
FIG. 25 is a diagram of a flow chart of a sequence operation request program in the monitor terminal operation computer of a fourth embodiment;
FIG. 26 is a diagram of a flow chart of a sequence control program in the sever computer of the fourth embodiment;
FIG. 27 is a diagram of a flow chart of a sequence control program in the sever computer of the fourth embodiment;
FIG. 28 is a diagram of flow charts of the server computer of the fourth embodiment;
FIG. 29 is a diagram of a flow chart of the server computer of the fourth embodiment;
FIG. 30 is a diagram of a flow chart of a center monitor operation program of the fifth embodiment;
FIG. 31 is a block diagram of a center monitor operation terminal computer in FIG. 13 of the fifth embodiment;
FIG. 32 is a diagram of a flow chart of a switcher circuit in FIG. 13 of the fifth embodiment;
FIG. 33 is a diagram of a flow chart of the program stored in the ROMs of the respective RF modems of embodiments of this invention;
FIG. 34 is a diagram of a flow chart of a program stored in the ROMs of the camera RF modem and monitor RF modems of embodiments of this invention; and
FIG. 35 is a diagram of the control signal RF modems in FIG. 1 of embodiment of this invention.
The same or corresponding elements or parts are designated with like references throughout the drawings.
DETAILED DESCRIPTION OF THE INVENTION
Hereinbelow will be described a first embodiment of this invention.
FIG. 1 is a block diagram of a video monitor system of the first to fourth embodiments. The video monitor system of the first embodiment comprises a camera portion 1 for receiving images and generating video signals, a monitor portion 2 for monitoring video signals, a recording portion 4 for recording videos signals, an operation terminal portion 5 for generating command signals as a control signal (data), a control portion 6 for controlling this system, and a transmitting medium 101 for transmitting video signals and control signals.
The transmitting medium comprises a coaxial cable 101 for transmitting sixteen channels of video signals and control signals multiplexed.
The camera portion 1 comprises two-hundreds of video cameras 102-1 to 102-200 as video signal sources for generating video signals from receivedimages at different locations respectively, camera RF modems 103-1 to 103-200 for modulating video signals, demodulating control signals, and receiving a synchronizing signal respectively, and bi-directional separators 104-1 to 104-200 for distributing modulated video signals, control signal and the synchronizing signal on the coaxial cable to the camera RF modems 103-1 to 103-200 and combining modulated video signals from the camera RF modems 103-1 to 103-200 with the modulated video signals, control signals, and the synchronizing signal on the coaxial cable 101.
The monitor portion 2 comprises sixteen sets of monitors 105-1 to 105-16, monitor RF modems 106-1 to 106-16, and bi-directional separators 107-1 to 107-16. The bi-directional separators 107-1 to 107-16 distribute the modulated video signals and control signals and receiving the synchronizing signal on the coaxial cable to the RF modems 103-1 to 103-200 respectively. The monitor RF modems 106-1 to 106-16 demodulate themodulated video signals, control signals, and receive the synchronizing signal on the coaxial cable 101 respectively. The monitor 105-1 to 105-16 reproduce video signals supplied from the monitor RF modems and display different images respectively.
The recording portion comprises a video tape recorder (VTR) 114, a video RFmodem 115, and bi-directional separator 116. The bi-directional separator 116 distributes the modulated video signals and the control signals and receiving the synchronizing signal on the coaxial cable to the VTR RF modem 115. The VTR RF modem 115 demodulates the modulated video signals and the control signals, and receives the synchronizing signal on the coaxial cable 101. The VTR 114 records video signals supplied from the VTRRF modem on a magnetic tape (not shown) in accordance with the received control signal in response to the synchronizing signal and reproduces the video signal from the magnetic tape in accordance with the received control signal in response to the synchronizing signal. The VTR RF modem 115 modulates the reproduced video signal and transmits the reproduced video signal to the coaxial cable 101 via the bi-directional separator 116for multiplexing.
The operation terminal portion 5 comprises bi-directional separators 110-1 to 110-4, control signal RF modems 109-1 to 109-4, monitor operation terminal computers 108-1 to 108-4. The bi-directional separators 110-1 to 110-4 distribute the control signals and receives the synchronizing signalon the coaxial cable to the control signal RF modems 109-1 to 109-4 respectively. The control signal RF modems 109-1 to 109-4 modulate the control signals including control data, and receives the synchronizing signal on the coaxial cable 101.
The control portion 6 comprises a bi-directional separator 113, a control signal RF modems 112, a server computer 111, and a synchronizing signal generation circuit 606. The synchronizing signal generation circuit 606 generates the synchronizing signal. The bi-directional separator 113 distributes the control signals from the coaxial cable 101 and supplies the synchronizing signal to the coaxial cable 101. The control signal RF modem 112 demodulates the modulated control signals including control data, and modulates control signals and transmits the synchronizing signalto the coaxial cable 101.
The camera may have a turn table mechanism (not shown) for controlling an angle of field, a focal length, and a direction of the camera in accordance with the control signal supplied from the camera RF modem 103.
FIG. 2 is a block diagram of the sever computer 111 of the first embodiment. The server computer 111 comprises a cpu (central processing unit) 206 for executing operations defined by control programs, a ROM 211 for storing a basic control program, a RAM (random access memory) 207 for storing data and programs, a hard disc unit 210 for storing data and programs, and an interface 205, coupled to the control signal RF modem 112, for receiving and transmitting control signals including command dataand control data. The hard disc unit 210 stores programs of an operation system 208, a monitor server task 209 including a connection control program 201, a monitor control program 202, a camera control program 203 including a priority control program 204. The cpu 206 transfers these programs in the hard disc unit 210 in accordance with the control program stored in the ROM 211 to the RAM 207 at an initial condition. FIG. 2 showsthis condition. The connection control program 201 is for controlling acquisition conditions of video channels of the coaxial cable 101 and controlling video signal connection condition of the whole system. The monitor control program 202 is for controlling an acquisition condition ofmonitors 105-1 to 105-16. The camera control program 203 is for controllingproviding rights of controlling through a judging in accordance with a predetermined rule when more than one monitor terminal computers request to control the same camera. The camera control program 203 includes the priority control program 204 for controlling priorities of the monitor operation terminal computers which is referred when more than one monitor terminal computers request to control the same camera.
FIG. 3 is a block diagram of the monitor operation terminal computer 108 ofthe embodiments of this invention. The monitor operation terminal computer 108 comprises a cpu 312 for executing operations defined by programs, a ROM 317 for storing a basic control program, a RAM (random access memory) 313 for storing data and programs, a hard disc unit 316 for storing data and programs, and an interface 311, coupled to the control signal RF modem109, for receiving and transmitting control signals including command data and control data. The hard disc unit 316 stores programs of the operation system 314 for effecting controlling for executing other programs, a monitor operation terminal task 315 including a monitor control program 301 for controlling monitors 105, a camera control program 304 for controlling cameras 102, and a camera information control program 308 for controlling information of a camera under acquisition.
The monitor control program includes a monitor acquiring program 302 for requesting the server computer 111 to acquire one of monitors 105 to display an image to be monitored and a monitor release program 303 for releasing the monitor acquired by the monitor acquiring program 302.
The camera control program 304 includes a right of control acquiring program 305 for requesting an acquisition of a right of controlling one ofcameras to the server computer 111, a camera operation program 306 for actually operating the camera 102 through a control signal, and a right ofcontrol release program for releasing the right of controlling the camera 102 acquired by the right of controlling acquiring program 305.
The camera information control program 308 includes a control information acquiring program 309 for holding control information of the camera of which the right of controlling is acquired by the right of controlling acquiring program 305 and a control information release program 310 for releasing the control information which has been held by the control information acquiring program 309.
The cpu 312 transfers these programs in the hard disc unit 316 in accordance with the control program stored in the ROM 317 to the RAM 313 at an initial condition of this monitor operation terminal computer 108. FIG. 3 shows the condition after the transferring.
FIG. 4 is a block diagram of a set of camera including a camera 102, a camera RF modem 103, and a bi-directional separator 104 of this invention shown in FIG. 1.
The camera RF modem 103 comprises a video signal modulation circuit 401 formodulating a baseband video signal outputted from the camera 102 into an RFsignal having a carrier frequency which can be changed and sends the modulated video signal to the bi-directional separator 104, a control signal demodulation circuit 402 for demodulating the control signal havinga predetermined carrier frequency from the bi-directional separator 104, a cpu 403 for effecting predetermined operations in accordance with the control signal demodulated by the control signal demodulation circuit 402 and sending a control signal from the camera 102 to the coaxial cable 101,a control signal modulation circuit 404 for modulating the control signal from the cpu 403, a synchronizing signal receiving circuit 405 for receiving a synchronizing signal transmitted on the coaxial cable 101, an interface circuit (I/F) 408 for supplying and receiving the control signalfrom the camera 102, a ROM 406 for storing programs to be executed by the cpu 403, and a RAM 407 for storing data and programs. The cpu 403 effects the operations such as a control of turn-ON or turn OFF of the carrier signal in the video modulation circuit 401, a requesting to change the modulation frequency, and supplying the control signal to the camera 102.
The cpu 403 receives the control signal from the bi-directional separator 104, the control signal from the camera 102, and the synchronizing signal from the synchronizing signal receiving circuit 405 by interruption processings.
FIG. 33 is a diagram of a flow chart of the program stored in the ROMs of the respective RF modems of embodiments of this invention.
When the cpu 403 detects the control signal from the bi-directional separator 104, the cpu 403 executes a program stored in the ROM 406 as shown in FIG. 33.
The cpu 403 receives the control signal and stores it in the RAM 407 in step 3301. In step 3302, the cpu 403 checks as to whether or not a commandin the control signal is directed to the camera RF modem 103 by checking anaddress in the control signal in step 3302. If the command is directed to the camera RF modem 103, the cpu 403 executes a corresponding processing of which program is stored in the ROM 406 in step 3303 such as a changing processing of the modulation channel and a transmission processing of a command to the camera 102. In the following step 3307 the cpu 403 stores conditional data of the camera and the video signal modulation circuit 401such as the used channel. If the command includes a request for transmitting a result in step 3304, the cpu 403 prepares a response message corresponding to the result of execution of the processing corresponding to the command in step 3305. The cpu 403 transmits the response message to the source of the control signal requesting the resultor a destination indicated in the control signal through the control signalmodulator 404 in step 3306.
FIG. 34 is a diagram of a flow chart of a program stored in the ROMs of thecamera RF modem 103 and monitor RF modems of embodiments of this invention.
When the cpu 403 receives the control signal from the camera 102, the cpu 403 executes the program stored in the ROM 406 as shown in FIG. 34. The cpu 406 receives the control signal from the camera 102 and stores it in the RAM 407 in step 3401. The cpu 403 prepares a transmission message by adding address data of destination to the stored control signal in step 3402. In the following step 3403, the cpu 403 transmits the transmission message through the control signal modulation circuit 404.
The synchronizing signal received by the synchronizing signal receiving circuit 405 is used in the cpu 403 during a synchronizing operation.
FIG. 5 is a block diagram of a set of monitor including a monitor 105, a monitor RF modem 106, and a bi-directional separator 107 shown in FIG. 1 of embodiments of this invention.
The monitor RF modem 106 comprises a video signal demodulation circuit 501 for demodulating the RF video signal having a carrier frequency which can be changed into a baseband video signal and sending the demodulated video signal to the monitor 105, a control signal demodulation circuit 502 for demodulating a control signal having the predetermined carrier frequency from the bi-directional separator 107, a cpu 503 for effecting predetermined operations for the monitor RF modem in accordance with the control signal demodulated by the control signal demodulation circuit 502 and outputting a control signal from the monitor 102, a control signal modulation circuit 504, a synchronizing signal receiving circuit 505 for receiving a synchronizing signal transmitted on the coaxial cable 101, an interface circuit (I/F) 508 for interfacing between monitor 105 and cpu 503, a ROM 506 for storing a programs to be executed by the cpu 503, and aRAM 507 for storing data and programs. The cpu 503 effects the operations such as a control of turn ON or turn OFF of the carrier signal in the video demodulation circuit 501, a control of changing the demodulation frequency, and outputting the control signal to and from the monitor 105.
The cpu 503 receives the control signal from the bi-directional separator 107, the control signal from the monitor 105, and the synchronizing signalfrom the synchronizing signal receiving circuit 505 by interruption processings.
When the cpu 503 detects the control signal from the bi-directional separator 107, the cpu 503 executes a program stored in the ROM 506 as shown in FIG. 33 as similar to the camera monitor RF modem 103. However, processings executed in step 3303 in response to commands directed to thismonitor RF modem 106 stored in the ROM 506 is such as a processing of changing demodulation channel to the video signal demodulation circuit 501which is specially provided to the monitor RF modem 106.
Moreover, when the cpu 503 detects a control signal from the monitor 105, the cpu 503 executes the program stored in the ROM 506 as shown in FIG. 34as similar to the camera RF modem 103.
The synchronizing signal received by the synchronizing signal receiving circuit 505 is used in the cpu 503 during a synchronizing operation.
FIG. 6A is a block diagram of a set of a monitor operation terminal including a monitor operation terminal 108, a control signal RF modem 109,and a bi-directional separator 110 in FIG. 1 of embodiments of this invention.
The control signal RF modem 109 comprises a control signal demodulation circuit 601 for demodulating a control signal having the predetermined carrier frequency from the bi-directional separator 110, a cpu 602 for effecting predetermined operations in accordance with the control signal demodulated by the control signal demodulation circuit 601 and outputting a control signal from the monitor operation terminal computer 108, and a control signal modulation circuit 603.
FIG. 6B is a block diagram of a set of a server including the server computer 111, a control signal RF modem 112, and a bi-directional separator 113 in FIG. 1 of embodiments of this invention. FIG. 35 is a diagram of the control signal RF modems 109 and 112 of embodiment of this invention.
The control signal RF modem 112 has substantially the same structure as thecontrol signal RF modem 109. A difference is in that a synchronizing signalgenerator 606 is further provided, the bi-directional separator sends the synchronizing signal, and an adder 605 are added. The synchronizing signalgeneration circuit 604 generates a synchronizing signal and the adder 605 adds the synchronizing signal to the modulated supplies control signal andsupplies the result to the bi-directional separator 113.
The cpu 602 receives the control signal from the bi-directional separator 110, and the control signal from the monitor operation terminal 108 by interruption processings in accordance with the program stored in the ROM 604 similar to the cpu 503 of the monitor RF modem 106 as shown in FIG. 33. However, processings executed in step 3303 in response to commands directed to this control signal RF modem 109 stored in the ROM 604 is suchas a forwarding processing of a received control signal to the monitor operation terminal computer 108 or the server computer 111 which is specially provided to the control RF modem 112.
On the other hand, when the cpu 602 detects a control signal from the monitor operation terminal computer 108 or the server computer 111, the cpu 602 executes a program also stored in the ROM 604 as shown in FIG. 35 which is similar to FIG. 33 except in that step 3508 is added.
The cpu 602 receives the control signal and stores it in the RAM 605 in step 3501. In step 3502, the cpu 602 checks as to whether or not a commandin the control signal is directed to this RF modem 109 or 112 by checking an address in the control signal. If the command is directed to this RF modem 109 or 112, in step 3503, the cpu 602 executes a corresponding processing of which program is stored in the ROM 604 such as a processing resetting an internal condition of the modem. If the command includes a request for transmitting a result in step 3504, the cpu 602 prepares a response message corresponding to the result of execution of the processing corresponding to the command in step 3505. The cpu 602 transmits the response message to the monitor operation terminal computer 108 or the server computer 111 using the interface 606 in step 3506.
In step 3502, when the control signal is not directed to this RF modem, thecpu 602 transmits the control signal to the coaxial cable 101 in step 3508.
An operation of monitoring a video signal will be described. For example, avideo signal from a video camera 102-1 is displayed on the monitor 105-1 inaccordance with processings represented by flow charts in FIGS. 16, 17, and18. FIG. 16 is a diagram of a flow chart of monitor acquiring program 302 of the first embodiment. In response to a manual operation to the keyboard318 by an operator, the monitor operation terminal computer 108-1 executes the monitor acquiring program 302 and in step 1601, the monitor operation terminal requests acquisition of the monitor 105-1 toward the server computer 111. FIG. 17 is a diagram of a flow chart of the connection control program 201 in FIG. 2 of the first embodiment. FIG. 18 is a diagram of a flow chart of the camera control program 203 in FIG. 2. In response to the request of acquisition of monitor 105-1 from the monitor terminal computer 108-1, the server computer 111 executes the connection control program 201. The server computer 111 receiving the request from the monitor operation terminal computer 108-1 as the control signal, makesa decision as to whether the monitor 105-1 has been acquired by another monitor operation terminal computer in step 1701. If the monitor 105-1 is not acquired, the server computer 111 renews a monitor connection table 212 in the RAM 207 to allow the monitor operation terminal computer 108-1 to use the monitor 102-1 in step 1702. In the following step 1703, the server computer 111 informs the monitor operation terminal computer 108-1 of success in the acquisition through the control signal. If the monitor 105-1-has been acquired in step 1701, the server computer 111 informs the monitor operation terminal computer 108-1 of failure in the acquisition through the control signal in step 1704.
Only one monitor 105 can be acquired by one of the monitor operation terminal computers 108 and it is possible to control a connection of a video signal to the monitor by only the monitor operation terminal computer 108 which has acquires the right of controlling the monitor 105.
In response to the information of the success in acquisition from the server computer 111, the monitor operation terminal computer 105-1 requests the server computer 111 to make a connection between the monitor 105-1 and the camera 102-1 in step 1603. The server computer 111 executes the camera control program 203 and in step 1801, the server computer 111 checks a connection condition of the camera 102-1 in a camera connection table 213 as to whether or not the camera 102-1 is being connected. If thecamera 102-1 has not been connected, since there is no channel which has been used for the camera 102-1, the sever computer 111 tries to acquire a channel for the camera 102-1 in step 1802. If the server computer 111 succeeds in the acquisition of the channel in step 1803, the server computer 111 commands the camera RF modem 103-1 through the control signalto change the channel of modulation to the acquired channel in step 1804 and renews a channel control table 214. In the following step 1805, the sever computer 111 commands the monitor RF modem 106-1 to change the channel to the channel connected to the camera 102-1 to modulate the videosignal from the camera 102-1. Then, the connection between the camera 102-1and the monitor 105-1 is provided. Then, the server computer 111 renews a connection condition table 213 indicative of a connection condition of themonitor 105-1 in step 1806. Then, the server computer 111 informs the terminal operation computer 108-1 of success in connection in step 1807.
In step 1803, the server computer 111 fails in acquiring a new channel, theserver computer 111 informs the terminal operation computer 108-1 of failure in acquisition of a new channel. In step 1801, if the camera 102-1has been connected, the server computer 111 commands the monitor RF modem 106 to change the channel to the channel connected to the camera 102-1 in step 1805.
During the operation mentioned above, the monitor operation terminal computer 108-1 and the server computer 111 communicate through the controlsignal RF modems 109-1 and 112 via the coaxial cable 101 and the server computer 111 sends the control signals to the camera RF modem 103-1 and tothe monitor RF modem 106-1 through the control signal RF modem 112 and the coaxial cable 101 to display a desired video signal from a desired camera on a desired monitor.
As mentioned, according to this embodiment, the server computer 111 having the connection control program 201 and the monitor control program 202 canprovide an image from a desired camera on a desired monitor under control by the server computer 111. Therefore, if there are many requests connection to the same monitor or to the same camera substantially at the same time, such connections can be provided under control by the server computer 111.
In this embodiment, the camera RF modem 103-1 to 103-200 can change the modulation channel. However, it is also possible to use modems in which modulation channels are fixed but different and carriers can be controlledbetween ON and OFF.
An operation of controlling a camera 102 will be described.
FIG. 19 is a drawing of a flow chart of a right of control acquiring program 305 in the monitor operation computer 108 of the first embodiment.FIG. 20 is a drawing of a flow chart of the priority control program 204 inthe server computer 111 of the first embodiment.
When there is a necessity of controlling a camera 102-2, in response to an operation of the keyboard 318, the monitor operation terminal computer 312makes a decision as to whether or not a right of control of the camera 102-2 has been acquired by checking whether or not information indicating that a right of control has received in step 1901. If the right of controlof the camera 102-2 has not acquired, the monitor operation terminal computer 108-1 requests the server computer 111 to provide the right of control of the camera 102-2 through the control signal in step 1902 and waits the result in step 1903.
The server computer 111 receiving the request judges whether the right of control of the camera 102-2 has been acquired by another terminal operation computer in step 2001. If the right of control of the camera 102-2 has not been acquired by another monitor operation terminal, the server computer 111 renews a table of right of control of cameras as to the camera 102-2, that is, a camera control table 216 in step 2005 and informs the monitor operation terminal computer 108-1 of success in acquiring right of control of camera 102-2 in step 2006.
Then, in step 1903, processing proceeds to step 1904 and the monitor terminal operation computer 108-1 holds the information of the right of control and information of controlling the camera 102-2. Then, the monitoroperation terminal computer 108-1 can control the operation of the camera 102-2 until the sever computer 111 commands the monitor operation terminalcomputer 108-1 to release the right of control of the camera 102-2 in step 1905.
If the right of control of the camera 102-2 has been acquired by the monitor operation terminal computer 108-2 yet in step 2001, the server computer 111 compares a priority A of the monitor operation terminal 108-1with a priority B of the monitor operation terminal 108-2 in step 2002 and 2003. In step 2003, if the priority of the monitor operation terminal 108-1 is higher than that of the monitor operation terminal 108-2, the server computer 111 informs the monitor operation terminal computer 108-1 of failure of acquiring the right of control of the camera 102-2 in step 2007. Therefore, the monitor operation terminal computer 108-1 cannot control the camera 102-2.
If the priority of the monitor operation terminal 108-2 is not higher than that of the monitor operation terminal 108-2, the sever computer 111 informs the monitor operation terminal computer 108-2 of losing the right of the control of camera 102-2 in step 2004. When the monitor operation terminal computer 108-2 which acquired the camera 102-2 is informed of losing the right of control of the camera 102-2, the monitor operation terminal computer 102-2 deletes the control information of the camera 102-2 in the camera control table 216 using the control information release program 310. Then, the monitor operation terminal computer 108-2 cannot control the camera 102-2.
On the other hand, server computer 111 provides the right of control of thecamera 102-2, that is, renews the camera control table 216 in step 2005 andinforms the monitor operation terminal computer 108-1 of success in acquiring the right of control of the camera 102-2 in step 2006. Then, themonitor operation terminal holds control information of the camera 102-2 instep 1904.
Then, the monitor operation terminal computer 108-1 can control the operation of the camera 102-2 by the camera operation program 306 until the sever computer 111 commands the monitor operation terminal computer 108-1 to release the right of control of the camera 102-2 in step 1905.
As mentioned, the cpu 602 of the control signal RF modems 109 and 112 executes processings in accordance with the flow charts shown in FIGS. 33 and 35 to provide a communication between the monitor operation terminal computer 108 and the server computer 111 and controlling the monitor RF modems 106 and camera RF modems 103 by the control signal RF modems 109 and 112. On the other hand, the cpu 503 of the monitor RF modem 106 and the cpu 403 of the camera RF modem 103 executes processings in accordance with the flow charts shown in FIGS. 33 and 34.
A second embodiment will be described.
The video monitor system of the second embodiment has substantially the same structure as the video monitor system of the first embodiment. A different between first and second embodiment is in the programs in the server computer and the RF modems. FIG. 7 is a block diagram of the servercomputer of the second embodiment.
That is, the hard disc unit 210 of the sever computer 111a stores a connection control program 701, a monitor control program 702, a system control program 703 and an address table 709. The cpu 205 transfers these programs and the address table 709 to the RAM 706 at the initial conditionin accordance with a program in the ROM 211. FIG. 7 shows the condition after transferring these programs and the address table of the second embodiment.
FIG. 21 is a diagram of a flow chart of the system control program 701 of the second embodiment shown in FIG. 7.
At the initial condition after the transferring the programs and the address table 709 in the hard disc unit 210 to the RAM 207, the cpu 206 executes the system control program 703 shown in FIG. 21. The server computer 111a commands the control signal RF modem 112 to transmit a control signal indicative of inquiring which video channel is used and commanding this inquiry to all modems, that is, the camera RF modems 104 and the monitor RF modems 106 in step 2101 through multiple addressing such as a broadcasting or a multi-cast function in the control signal RF modem 112 in accordance with an address table 709 storing addresses of RF modems 103, 106, 109, and 112 correspondingly storing information of videosignal outputting or inputting condition. The control signal RF modem 112 generates the control signal indicative of inquiring which video channel is used and transmits this inquiry to more than one of the camera RF modems and more than one monitor RF modem 106 using the multiple addressing function through the control signal modulation circuit 603.
When each of the modems receiving the inquiry, the cpu 403 and the cpu 503 respond this inquiry and transmit answers, that is, the conditional data of a video-signal-outputting condition including data indicative of which channel is used and information of video-signal-inputting condition including data indicative of which channel is used to the server computer 111a. This conditional data is stored in step 3307 shown in FIG. 33.
The server computer 111a waits the responses from the modems to which the server computer 111a transmitted the inquiry for a predetermined interval in step 2102, 2103, and 2104. The server computer 111a receives the answers in step 2102 and stores the answers in step 2106. In step 2104, ifany of RF modems to which the server computer 111a transmitted the inquiry does not respond the inquiry within the predetermined interval, the servercomputer 111a inhibits use of the modem to which the server computer 111a transmitted the inquiry and does not respond the inquiry within the predetermined interval to use in step 2105. That is, when the server computer 111a executes the connection control program 701, the server computer 111a does not connects that modem in accordance with this result,i.e., inhibition of use.
In this embodiment, the server computer 111a can detect a trouble portion. FIG. 8 is a block diagram of an example of a video monitor system of the second embodiment indicating the trouble portion. In FIG. 8, a trouble occurs in the coaxial cable 101 between the bi-directional separators having addresses A2 and A3. FIG. 9 is a diagram of an address table of thesecond embodiment shown in FIG. 7 explaining the condition of occurrence ofthe trouble portion, for detecting the trouble portion.
The server computer 111a executes the system control program 703b to detecta trouble portion.
At the initial condition after the transferring the programs and the address table 709 in the hard disc unit 210 to the RM 207, the cpu 206 executes the system control program 703b shown in FIG. 22 or executes the system control program 703b periodically. The server computer 111a commands the control signal RF modem 112 to transmit a control signal indicative is used and used video channel is used and commanding this inquiry to more than one of camera RF modems 103 and to more than one of monitor RF modems 106 in step 2201 through multiple addressing such as thebroadcasting or the multi-cast function in the control signal RF modem 112 in accordance with the address table 709 storing addresses of RF modems 103, 106, 109, and 112 and correspondingly storing information of video signal outputting or inputting condition. The control signal RF modem 112 generates the control signal indicative of inquiring which video channel is used and transmits this inquiry to more than one of the camera RF modems and more than one monitor RF modem using the multiple addressing function through the control signal modulation circuit 603 in step 2201.
Each of the modems receiving the inquiry, the cpu 403, and the cpu 503 respond this inquiry and transmit answers, that is, information of a videosignal outputting condition including data indicative of which channel is used and information of a video signal inputting condition including data indicative of which channel is used to the server computer 111a.
The server computer 111a waits the responses from the RF modes to which theserver computer 111a transmitted the inquiry for a predetermined interval in step 2202, 2203, and 2204. The server computer 111a receives the answers in step 2202 and stores the answers in step 2205. In step 2204, ifany of RF modems to which the server computer 111a transmitted the inquiry does not respond the inquiry within the predetermined interval, processingproceeds to step 2205. Then, in step 2206 the server computer 111a predictsa trouble potion from data the RF modems to which the server computer 111a transmitted the inquiry with the RF modems responding this inquiry and a connection relation represented by the address table shown in FIG. 9.
This results is also stored in the address table 709 with a correspondence with the addresses of RF modems.
When the server computer 111a executes the connection control program 701, the server computer 111a uses this result from the address table 709.
As shown in FIG. 9, the address table formed in the RAM 313 includes information of kinds of each of units, that is, the camera 102, the monitor 105, the monitor operation terminal computer 108, and the server computer 111a, a connection relation with neighbor terminals, and the result (response 804) of the answer mentioned above with a correspondence with address 802. If the trouble portion occurs as shown in FIG. 8, the camera RF monitors having addresses A1 and A2 do not response to the inquiry from the server computer. The camera having address A2 locates between the cameras having addresses A1 and A3, which is represented by the data 803 in the column of kind and address of neighbour modem. Therefore, the server computer 111a having an address A221 can predicts that the trouble occurs between the cameras having addresses A2 and A3.
As mentioned, according to this embodiment, not only trouble in a modem butalso a trouble in a network can be detected by providing diagnostic functions with the system control programs 703a and 703b in the server computer 111a.
A third embodiments will be described.
FIG. 10 is a block diagram of the server computer 111b of the third embodiment.
A video monitor of the third embodiment has an optional modes such as an alarm activating mode and a timer operation mode in addition to the basic operation as described in the first embodiment. The basic structure is similar to that of the first embodiment. A different between the first andthird embodiments is in that a system operation control program 1003 including an alarm operation control program 1004 and a timer operation control program 1005 and a timer 213 are further provided and the camera modem 401 receives and sends an alarm signal to the server computer 111b. These programs in the hard disc unit 210 and transferred to the RAM 207.
The server computer 111b receives a control signal indicative of the alarm signal from the camera RF modem 103 or the like transmitted through the coaxial cable 101 and executes the alarm operation control program 1004 inresponse to this. Moreover, the server computer 111b executes a predetermined operation in response to the timer 213 at a predetermined timing. The server computer 111b stores data of operational conditions (conditional data) before executing the alarm operation or the timer operation and after completion of the alarm operation or the timer operation, the server computer 111b recovers the operational condition to the former condition with the system operation control program 1003.
FIG. 23 is a diagram of a flow chart of the alarm operation control programin the server computer 111b of the third embodiment.
When the control signal indicative of alarm is transmitted from one of the camera RF modems 103, the server computer 111b receives the control signaland executes the alarm operation control program 1004. In step 2301, the server computer 111b stores or preserves conditional data such as the connection condition data or data stored in the address table in step 2302. In the following step 2102, the server computer 111b executes an alarm processing in accordance with the kind of the alarm in step 2303. The server computer 111b stops the alarm operation processing when a predetermined interval has passed in step 2305 or a request for stopping the alarm operation processing from one of monitor operation terminals 108in step 2304. Then, the server computer 111b stops the alarm operation processing in step 2306 and reads the stored conditional data from RAM 207and executes the normal control processing mentioned in the first embodiment using this conditional data of the operational condition.
FIGS. 24A and 24B are diagrams of flow charts of the third embodiment. The server computer 111b receives a control signal indicative of a request forthe timer operation including data of a start time and a kind of timer operations in step 2408. Then, the server computer 111b sets and starts the timer 213 and permits the timer interruption.
When the start time has come, the server computer 111b responsive to the timer 213 executes the processing shown in FIG. 24B, in step 2401, the server computer 111b stores or preserves conditional data such as the connection condition data or data stored in the address table. In the following step 2402, the server computer executes the timer operation in accordance with the data indicative of the kind of the timer operation in step 2403. The server computer 111b stops the timer operation processing when a predetermined interval has passed in step 2405 or a request for stopping the timer operation processing from one of monitor operation terminals 108 in step 2404. Then, the server computer 111b stops the timeroperation processing in step 2406 and reads the stored operational data from RAM 207 and executes the normal control processing mentioned in the first embodiment using this data of the conditional data again.
As mentioned, according to the third embodiment, the alarm operation and the timer operation or the like can be executed during the normal operation by providing the system operation control program 1003 for storing the video signal connection condition. This operation makes it possible to turn on a light (not shown) provided adjacent to the camera modem which sent the alarm in response to the alarm and to change monitoring locations in accordance with day time or night time or the day of the week.
A fourth embodiment will be described.
The video monitor system of the fourth embodiment performs a sequence controlled monitoring operation and an effective recording operation of the video signal.
FIG. 11 is a block diagram of a server computer 111c of the fourth embodiment.
The basic structure of the fourth embodiment is similar to that of the first embodiment. A different between the first and fourth embodiments is in that a sequence control program 1103a and 1103b for generating command data for controlling the monitor RF modems 105 and the camera RF modems 103 and a video recording condition control program 1104 for generating command data through the control signal for controlling start and stop of recording by the VTR 114 are further provided in the hard disc unit 210 and transferred to the RAM 207.
FIG. 12 is a block diagram of a set of VTR portion including the VTR 114, aVTR RF modem 115, and a bi-directional separator 116 of this invention shown in FIG. 1.
The VTR RF modem 115 comprises a video signal demodulation circuit 1201 fordemodulating the RF video signal having a carrier frequency, which can be changed (a channel is selected), into a baseband video signal and sending the demodulated video signal to the VTR 114, a control signal demodulationcircuit 1202 for demodulating a control signal having the predetermined carrier frequency from the bi-directional separator 116, a ROM 1206 for storing programs, an interface circuit 1208 for interfacing between VTR 114 and cpu 1203, a RAM 1207 for storing data and programs, a cpu 1203 foreffecting predetermined operations in response to the control signal demodulated by the control signal demodulation circuit 1202 in accordance with programs stored in the ROM 1206 and sending a control signal from theVTR 114, a control signal modulation circuit 1204, and a synchronizing signal receiving circuit 1205 for receiving the synchronizing signal transmitted on the coaxial cable 101. The cpu 1203 effects the operations such as a control of turn-ON or turn OFF of the carrier signal in the video signal demodulation circuit 1201, a control of changing the modulation and demodulation frequency, and outputting the control signal from the monitor 1203 in response to the control signal from the bi-directional separator 116 in accordance with the programs stored in theROM 1206 using an interruption as shown by the flow chart in FIG. 31 as similar to the monitor RF modem 106. However, processings executed in response to commands directed to this VTR RF modem 1201 stored in the ROM 1206 is such as a transmitting processing of a received control signal to the VTR 114, which is specially provided to the VTR RF modem.
On the other hand, when the cpu 1203 detects a control signal from the VTR 114, the cpu 1203 executes the program also stored in the ROM 1206 as shown in FIG. 33 as similar to the camera RF modem 103.
The camera RF modem 103 and the monitor RF modem 106 have sequence operation storing functions and sequence operation executing functions. These functions are performed by the cpu 403 and the cpu 503 in accordancewith programmes as shown in FIG. 33, stored in the ROM 406 and ROM 506, forthese functions. The RAM 407 and RAM 507 are used to store the sequence operations.
The control signal RF modem 112 connected to the server computer 111 has a broadcasting function for providing broadcasting or multi-casting operation toward a plurality of camera RF modem 103 and a plurality of monitor RF modem 106.
Moreover, the monitor operation terminal computer 108 has a program for setting the sequence operation and producing a request of the sequence operation.
In the sequence operation, a plurality of monitors display images from a plurality of cameras such that an image on a monitor is periodically switched from one of video signals in one group of cameras and an image onanother monitor is periodically switched from one of video signals from another group of cameras, wherein both images on the monitors are switchedat the same timing.
FIG. 25 is a diagram of a flow chart of a sequence operation request program in the monitor terminal operation computer 108 of the fourth embodiment.
FIG. 26 is a diagram of a flow chart of a sequence control program 1003a inthe sever computer 111c of the fourth embodiment.
FIG. 27 is a diagram of a flow chart of a sequence control program 1003b inthe sever computer of the fourth embodiment.
The monitor operation terminal computer 108 requests the server computer 111c to allow to use monitors 105 and cameras 102 which are necessary for the sequence operation in step 2500 in response to a manual operation through the keyboard. In response to this, the server computer 111c executes the connection control program 201 and informs the monitor terminal operation computer 108 of the result.
In step 2501, if result shows that the monitor operation terminal computer succeeds in using the necessary monitors and the necessary cameras processing proceeds to step 2502. If the monitor operation terminal computer fails in using the necessary monitors and the necessary cameras processing ends.
In step 2502, the monitor terminal operation computer 108 requests the server computer 111c to set it to a sequence operation.
In response to this, the server computer 111c executes the sequence controlprogram 1103a.
In step 2603, the server computer 111c commands RF modems 103 and 106 to set data for sequence control to prepare the sequence operation. That is, the server computer 111c commands the monitor RF modems 106 and the cameraRF modems 103 necessary for the sequence operation to store steps of a sequence operation and transmits the steps. Then, the server computer 111csets a multi-cast address to respective modems for the sequence operation to send each of steps of the sequence operation to the necessary RF modemsat the same time.
Then, the monitor operation terminal computer 108 requests to start the sequence operation in step 2503.
In response to this, the server computer 111c executes the sequence controlprogram 1103b. In step 2701, the server computer 111c initializes data for the sequence operation. In the following step 2702, the server computer 111c requests the necessary RF modems to execute a next step of the sequence operation. In step 2703, if a time period of the sequence operation has passed, the server computer 111c requests the necessary RF modems to execute a next step of the sequence operation in step 2702. If the time period of the sequence operation has not passed, the server computer 111c checks whether or not there is a request for stopping the sequence operation in step 2704.
On the other hand, the monitor terminal operation computer 108 waits a stopcommand from the keyboard in step 2504 and 2505. If there is the stop command from the keyboard, the monitor operation terminal computer 108 requests the server computer 111c to stop the sequence operation in step 2506.
The server computer 111c executes a sequence operation completion processing in step 2705 when the request for stopping sequence operation is detected in step 2704. In the following step in 2705, the server computer executes the sequence operation completion processing to restore the condition of the video monitor system in the normal mode.
FIG. 28 is a diagram of flow charts of the server computer 111c of the fourth embodiment. FIG. 29 is a diagram of a flow chart of the server computer of the fourth embodiment.
On starting recording a video signal, the server computer 111c sends data of channel of a video signal to be recorded to the VTR RF modem 115 and commands the VTR RF modem 115 to start recording the video signal of the channel in step 2801 with the video recording condition control program 1104 in the server computer 111c.
The control signal demodulation circuit 1201 in the VTR RF modem 1201 demodulates the control signal and receives the data of channel to be usedand the command for start of recording and the modem command processing circuit 1203 commands the video signal demodulator to set the channel and the VTR 114 to record the video signal from the video signal demodulator 1201.
On stopping recording the video signal, the server computer 111c commands the VTR RF modem 115 to stop recording the video signal of the channel in step 2802 with the video recording condition control program 1104 in the server computer 111.
The control signal demodulation circuit 1201 in the VTR RF modem 1201 demodulates the control signal and receives the command for stopping recording and the modem command processing circuit 1203 commands the videosignal demodulator to stop recording the video signal from the video signaldemodulator 1201.
When a camera from which the video signal to be recorded is sent is changedto another camera, the server computer 111c requests the VTR RF modem 115 to stop recording in step 2901. Then, the server computer 111c requests a camera RF modem of the camera to be coupled the VTR 114 to change the channel to the channel selected by the VTR RF modem 115 with a synchronizing operation. In the following step 2903, the server computer 111c request the VTR modem 115 to start recording with the synchronizing operation. Then, the camera RF modem 103 of the camera to be coupled the VTR 114 changes the channel to the channel selected by the VTR RF modem 115 in response to the synchronizing signal and the VTR modem 115 also starts recording in response to the synchronizing signal from the synchronizing signal receiving circuit. Therefore, the camera RF modem of the camera to be coupled the VTR 114 changes the channel to the channel selected by the VTR RF modem 115 and the VTR modem 115 starts recording atthe same time in response to the synchronizing signal as the synchronizing operation.
As mentioned, according to the fourth embodiment, the connection control program 201 and the video signal recording condition control program provides the controlling of the VTR with the synchronizing operation, so that a necessary video image can be recorded efficiently without a disturbance of image on the reproduced image. The VTR may be replaced by aphoto-electro-magnetic disc recording unit or the like.
A fifth embodiment will be described.
FIG. 13 is a block diagram of a video monitor system of the fifth embodiment. FIG. 14 is a block diagram of a set of center monitor of fifthembodiment. FIG. 30 is a diagram of a flow chart of a center monitor operation program of the fifth embodiment. FIG. 31 is a block diagram of acenter monitor operation terminal computer 1306 shown in FIG. 13. FIG. 32 is a diagram of a flow chart of a switcher circuit shown in FIG. 13.
The video monitor system of the fifth embodiment comprises a plurality of video monitor networks, at least a center monitor set, and a center monitor operation terminal computer set. Each of the video monitor networks correspond to the video monitor system of the first embodiment shown in FIG. 1. FIG. 31 is a block diagram of the center monitor operation terminal set including a center monitor operation terminal computer 1306, control signal RF modems 1307 for communicating with the coaxial cable 1302-1 of the video monitor system 1301-1, and a control signal RF modem 1308 for communicating with the a coaxial cable 1302-2 of the video monitor system 1301-2.
The basic structure of the center monitor operation terminal computer 1306 is similar to that of the monitor operation terminal computer 108 shown inFIG. 3. A different is in that a center monitor operation program is storedin the hard disc unit 3103 which is transferred to the RAM 3105 at an initializing.
The switcher RF modem 1314 or 1320 comprises a video signal demodulation circuit 1401 for demodulating the RF video signal having a carrier frequency which can be changed into a baseband video signal and sending the demodulated video signal to the switcher circuit 1312 or 1318, a control signal demodulation circuit 1402 for demodulating a control signalhaving the predetermined carrier frequency from the bi-directional separator 1316 or 1322, a cpu 1403 for effecting predetermined operations in accordance with the control signal demodulated by the control signal demodulation circuit 1402 and sending a control signal from the monitor 1311, an interface circuit 1408 for interfacing between the switcher circuit 1312 or 1318 and the cpu 1403, a RAM 1407, a ROM 1406, a control signal modulation circuit 1404, and a synchronizing signal receiving circuit 1405 for receiving a synchronizing signal transmitted on the coaxial cable 1302-1. The cpu 1403 effects the operations such as a control of turn-ON or turn OFF of the carrier signal in the video demodulation circuit 1401, a control of changing the modulation frequency,outputting the control signal from the monitor 1405, and changing a switch 1410 in the switcher circuit 1312 or 1320. The channel of the switcher circuit is changed in accordance with the control signal from the switcherRF modulation modems 1314 or 1320.
The cpu 1403 receives the control signal from the bi-directional separator 1316, 1322, the control signal from the switcher circuit 1312, 1318, and the synchronizing signal from the synchronizing signal receiving circuit 1405 by interruption processings.
When the cpu 1403 detects the control signal from the bi-directional separator 1316, 1322, the cpu 1403 executes a program stored in the ROM 1406 as shown in FIG. 31 as similar to the monitor RF modem 106. However, processings executed in response to commands directed to this switcher RF modem 1314 or 1320 stored in the ROM 1406 is such as a processing of switching to the switcher circuit 1312, 1318 which is specially provided to the switcher RF modem 1314 or 1320.
Moreover, when the cpu 1403 detects a control signal from the switcher 1312, 1318, the cpu 1403 executes the program stored in the ROM 1406 as shown in FIG. 33 as similar to the camera RF modem 103.
Moreover, the synchronizing signal is used in the cpu 1403 to execute a processing requiring a synchronizing operation in the network of the videomonitor system.
The center monitor operation terminal computer 1306 executes the center monitor operation program 3107 in response to a command from a key board 3102 for example as follows:
In this embodiment, the center monitors 1311 and 1317 are controlled under both server computer 1303-1 and 1303-2. That is, a connection condition cannot be changed if both server computers 1303-1 and 1303-2 do not allow to change the connection condition. However, if either of the server computers is failure, the connection condition can be changed by only the other server computer.
In step 3001, a decision is made as to whether no server computer is available. If no server computer available, processing ends. If at least aserver computer is available, processing proceeds to step 3002. In step 3002, a decision is made as to whether the server computer 1303-1 is available. If NO, processing proceeds to step 3005. If only the server computer 1303-1 is available, the center monitor operation terminal computer 1306 requests the server computer 1303-1 to acquire the center monitor 1311. If the server computer 1303-1 successes in acquiring the center monitor 1311, processing proceeds to step 3005. If NO, processing ends.
In step 3005, a decision is made as to whether the server computer 1303-2 is available. If NO, processing ends. If only the server computer 1303-2 is available, the center monitor operation terminal computer 1306 requeststhe server computer 1303-2 to acquire the center monitor 1311. If the server computer 1303-2 succeeds in acquiring the center monitor 1311, processing proceeds to step 3008. If NO, processing ends.
In step 3008, the center monitor operation terminal computer 1306 requests the available server computer 1303-1 or 1303-2 to connect a camera 1305-1 to the center monitor 1311. If the center monitor operation terminal computer 1306 succeeds, the center monitor operation terminal computer 1306 requests the switcher RF modem 1314 to change the channel to the sideof the video monitor network 1301-1 in step 3010.
The server computer 1303-1, the monitor RF modem 1313, the camera RF modem change the connection condition as similar to the first embodiment. In steps 3201 and 3202, the switcher circuit 1312 changes the channel to the monitor RF modem 1313 in response to the request in step 3010 from the center monitor operation terminal computer 1306.
In the flow chart shown in FIG. 30, if both are trouble in step 3001, the center monitor operation computer fails in acquisition of the center monitor 1311. In this example shown in FIG. 13, if there is a trouble in either of server computer and there is a request for using a camera under control of this server computer, the camera cannot be controlled and this connection results in fail.
As mentioned above, according to the large-scale video monitor system of this embodiment, the operation to the center monitor operation terminal computer 1306 selectively provides a video image from a plurality of videomonitor systems (networks). Moreover, the server computers are provided to respective networks, so that a trouble in one network does not affect to monitoring in the other network.
According to embodiments as mentioned, it is possible to provide cameras and monitors of which number is larger than the number of the channels of the cable. Moreover, if there is a collision between requests for one camera, the requests can be processed in accordance with the priority assigned to the monitors. Moreover, a trouble in the modem or the network can be detected. Further, a predetermined operation can be effected in response to an alarm or a timer and the operation can be restored after a predetermined interval. Moreover, the sequence operation can be provided and a video signal can be recorded efficiently. Further, the large-scale video monitor system including a plurality of video monitor systems can beprovided. | A video monitor system comprises a transmitting medium, video cameras, monitors, VTR, monitor terminals, a control portion and a transmitting medium having channels of video signals and a data channel coupling these units. The video monitor receives a request of a desired camera and a desired monitor and supplies the data indicative the request. The control portion receives the data indicative of the request and determines one of channels and operates the desired camera and desired monitor thorough the determined one of channels to display a video signal on the desired monitor. The VTR records one of video signals from a desired video camera through determined one of channels. A priority is judged to control one video camera which are requested to be operated by two monitor control terminals at the same time. A diagnostic function for detecting a defect and a location in the transmitting medium and a sequential operation function are also provided. The control portion operates in two modes which can be alternately executed by storing conditional data of two modes. An integrated video monitor system having two video monitor systems mentioned above and a center monitor for displaying a video signal from either of one of video camera of either of the monitor systems is also disclosed. | 7 |
This application is a continuation of application Ser. No. 07/564,565 filed Aug. 9, 1990, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a power controller for providing power to a personal computer and associated peripheral devices. Current power controllers for personal computers primarily involve protecting the personal computer from power surges, noise that comes from standard AC power, and power outages or blackouts. These power controllers arc generally confined to outlet strips that enable a computer and several peripheral devices to be connected to the power strip which is connected directly to a standard AC wall outlet. The power strips generally include circuitry involving power surge suppression and noise filtration. Some power controllers also include backup power supply in the form of a strong battery that can sustain the computer if a power outage or blackout occurs. This conventional power controller devices function to transmit power to a computer and peripheral devices, but generally fail to involve any operative functions of the computer or its peripheral devices.
In computer systems, there is a problem of how to conveniently turn on the CPU and peripherals from the desktop. This problem is commonly handled by the use of a manually operated master switch on a conventional multi-outlet power strip. This approach however requires that the power strip be located next to the computer, something that is often undesirable. Another approach is to use a power strip which is remotely controlled by a smaller switching unit, located at the desktop. This still suffers the problem of requiring an additional piece of equipment on the desk.
One computer that addresses the issue of powering up a computer from the desktop is the Macintosh II™ line of personal computers from Apple Computers™. This line of computers involves a unique device for allowing the computer and its monitor to be switched on directly from its keyboard. A special key on the keyboard sends a signal to the internal power supply of the computer to power up the computer and monitor. The device also allows the computer to be shut down directly from the operating system's menu. This feature of the Macintosh II line of computers has proven very convenient to computer users. However, it has several drawbacks as far as addressing the overall supply of power to any personal computer. First, it can only power up the computer and its monitor. In today's personal computing environment, there arc a host of peripheral devices such as external drives, printers, and special input devices that are externally connected to the computer. Thus, even though the start up feature of the Macintosh II is convenient, any external peripheral devices must still be individually switched on. Second, the internal power supply of the Macintosh II doesn't provide some of the standard features of conventional power strips, such as surge suppression. Finally, the keyboard switching feature only works on the Macintosh II line of computers. Other Macintosh computers as well as other personal computers do not have such a desktop power up feature.
A second problem within the field of power control for computers is the lack of ability to turn on a computer system when no operator is present. This problem can be handled in some situations by plugging the computer system into a timed outlet. This approach does not work with all computers, as some have their own internal "soft" switching and will remain oft after power has been removed and reapplied. Also this requires a separate timer unit which again is often either inconvenient to access or in the way. And finally, such units usually very limited programmability.
A third problem often encountered is that of needing to turn on a computer system from a remote location. This need usually arises when it is necessary to retrieve information from one unattended computer via a phone modem from a computer in another location. One approach has been to use a modem to signal the computer to turn itself on. The major drawback to this approach is that it only works for computers that have the ability to turn themselves when signalled.
There has been a need within the field of power controllers tier computer devices for a unique device that handles basic power control features and additionally handles the power up of computers and peripherals.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a device for handling the basic features of external power control tier personal computers including surge suppression and noise filtration.
Another object of the invention is to provide a device that allows a computer and severed peripheral devices to power up from the pressing of a key on the keyboard.
It is a further object of the invention to provide a device that would allow the computer to be turned on at a specified time to allow remote access to the computer or allow a proprogrammed set of events to occur without requiring the attention of a computer operator.
Other objects of the invention will be apparent hereinafter from the specification and from the recital of the appended claims, particularly when read in conjunction with the accompany drawings.
The present invention comprises a single external device for controlling power delivered to a computer and several peripheral devices. The device is directly connected to an AC power source and includes a plurality of outlets to connect the personal computer and least one peripheral device to the power controller device of the present invention. The device includes circuitry to suppress power surges, prevent power overloads, and filter noise that is associated with any AC power supply. The device further includes a connection between the device and a computer's special port for connecting the keyboard, mouse and other input devices to the computer. The connection of the device to the special port in addition to special circuitry within the power controller device allows the computer and peripherals to power up in response to a keystroke on the computer's keyboard. Additional timer circuitry is provided within a microcontroller of the device to allow the computer system to power up at a specified time or power up in response to a telecommunication signal for allowing remote access to the computer through a modem. The timer circuitry also allows the computer to be programmed for other scheduled on/off functions.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a perspective view of the power controller device of the present invention.
FIG. 2 shows an opposite perspective view of the device from the one shown in FIG. 1.
FIG. 3 shows a perspective view of the device similar to FIG. 2 with several power cords from a computer and peripheral devices connected directly to the power controller device of the present invention.
FIG. 4 shows a plan view of the power controller device in a typical application of the present invention showing its connection to a computer and one peripheral device.
FIG. 5 shows a block diagram of the present invention showing the relationship of the various internal functions.
FIG. 6 is an electronic schematic diagram of the present invention.
FIG. 7 shows an electronic circuit diagram of a second embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1 and 2 show the preferred embodiment of the power controller device 1 of the present invention. The device includes an outer housing 2 that holds all of the circuitry that controls the device. On one end 3 of the housing is disposed a pair of outlets 4 into which a personal computer or peripheral device may be connected. A power cord 5 extends from the end 3 and is connected to any standard 120V AC power outlet. FIG. 2 shows an opposite end 6 of housing 2 that includes two more outlets 4. A connector 7 is also shown on the opposite end 6 for connecting a computer cable 8 to the device. The computer cable connects the power controller to one of the computer's data ports so that the power controller may send and receive instructions to and from the computer. Details of cord 8 will be explained, below.
FIG. 3 shows the device partially connected to a computer system. In this view, a computer is about to be connected to the power controller device 1 through the computer's power cord 9. The plug at the end of cord 9 is plugged into any one of the four outlets 4. Three peripheral devices are shown connected to the device 1 through their respective power cables 10. Final operative connection of the power controller device involves connecting the device's power controller cord 5 to a standard AC power outlet, and connecting the computer cable 8 to the computer. In the configuration shown in FIG. 3, the computer and all three peripheral devices can be powered up by the device 1.
FIG. 4 shows a schematic of another computer system using the same power controller device as the system shown in FIG. 3. In this system, only one peripheral device is shown for clarity reasons. The system includes a computer 11 with an integral monitor (not shown in this view). The computer is connected to the power controller device 1 through its power cable 9. A peripheral device 12, shown here as a serial printer, is also connected to the power controller device 1 through its power cord 10. The computer cable 8 is a specially configured cable: that is formed as a three leg Y-type cable. The first leg 13 of the Y-type cable 8 is connected to the computer while the second leg 14 is connected to the computer's keyboard 17. The first and second legs are joined together at a T connector 15 that connects into one of the ports of the computer. The second leg 14 of cable 8 includes a female connector head which is connected to a keyboard cable 18 through its male connector head or plug 19.
The system shown in FIG. 4 is patterned after a Macintosh SE™ personal computer made by Apple Computer™. This type of computer has an Apple Desktop Bus™ or ADB port that allows a keyboard 17, mouse 20, or any other type of input device to be connected in series to the computer 11. The power controller device 1 of the present invention connects into the ADB port through connector 15 of the Y cable 8. It should be noted that the invention is applicable to other types of computer systems using different ports. The system shown is by way of example, only.
An optional third leg 22 of the Y cable is connected to a modem 23 which is connected to a telecommunication line by a telephone connector head 24. Leg 22 is also connected to the T connector 15. By using this optional third leg of the cable it is possible to power on the computer system remotely through the use of the modem.
Once all of the cables are connected to the computer 11, keyboard 17 and/or power controller device 1, the device is connected to an AC power supply through the power cable 5. In operation, the computer system is powered up by pressing a special key 21 of the keyboard 17. Pressing key 21 sends a signal through the ADB cords 18 and 8 to the power controller device 1. Programmable circuitry in the device can interpret this signal as a "power on" signal. The circuitry then switches the computer 11 and all peripheral devices such as printer 12 to an "on" condition. The computer system can be shut down just as easily from the computer's operating system menu which sends a signal through the ADB port to the device 1 which subsequently switches the computer and all peripheral devices to the "power off" condition.
In addition to its operative function of providing a convenient "on-off " switch for the computer system, the device also has surge suppression, overload protection, and noise filtration functions conventional on most external power controller devices. Furthermore, the power controller device 1 is also useful as a means for allowing the computer to operate without a user. The device includes timer circuitry for allowing the computer to be turned on at a specific time. Once the computer is on, a telecommunication program in combination with a modem can be programmed to dial up an on-line database and download information into the computer. This feature is very convenient for obtaining information from databases that are continuously updated, and where the computer operator does not have the time to access the database on a regular basis. One example of such a database would be a New York Stock Exchange database that continually updates a computer user on stock prices, movements, etc.
Another use of the programmable aspect of the power controller device is the ability to use the computer as a remote host computer when the user is on the road, at home, or at another office. The ability to switch on the computer at a predetermined time or directly over the modem by the use of the optional modem cable, allows the user to access any of the information in the host computer while working on a portable computer. Through the use of special communications software, a user can effectively use the portable computer as a "dumb" terminal to the host computer that is connected to the power controller device 1.
FIG. 5 shows a block diagram of the control elements of the present invention. AC power is first passed through a 15A circuit breaker to protect the attached equipment and the unit itself in the event an overload condition should occur. The power next passes through a simple surge suppression and noise filtration stage to reduce electrical noise and surges.
This filtered power is then passed through a power relay to the controlled receptacles as well as to an internal power supply circuit used to power the controlling electronics and to provide a timebase for the internal timekeeping. The internal power supply is always powered.
The controlling electronics consists of a microcontroller with oscillator circuitry and associated driver electronics. The microcontroller is responsible for the following functions:
1) Monitoring the keyboard, looking for the operator to press the key designated to turn the outlets on.
2) Communicating with the master computer through the keyboard interface, handling the required communications protocol. (In the case of a system based on a Macintosh SE, this protocol is called the Apple Desktop Bus™ or
3) Maintaining timing information, used to turn the outlets on or off at preset times.
4) Maintaining status information and user settings.
5) Controlling the power switching to one or more outlets.
6) Sending an "on" signal to the computer.
7) Monitoring and reporting the status of various internal and external signals to the master computer.
8) Switching the relay during power line "zero crossings" to reduce current surges and interactions between equipment.
9) Switching computer back on after a power failure.
The driver electronics are used to control the keyboard interface, the power relay(s) and to signal the computer to turn on.
The microcontroller is always on, receiving its power exclusively from the internal power supply. Using the power line frequency as a timebase, it is able to maintain real-time counters which are used for event scheduling.
Referring to FIG. 6, the basic electronic elements can be seen when compared to the block diagram of FIG. 5. The AC power source is shown at the upper left corner of the schematic where the AC power is passed through a surge suppressor, a noise filter and a circuit breaker to protect the computer from power overloads. These elements arc shown to the right of the AC power source. The power supply is shown in the upper right corner of the schematic and sends power to the four outlets shown next to the relay. Below the relay is shown the microcontroller which controls the relay.
The microcontroller processes information from the computer and its keyboard and opens or closes the relay in response to certain information received by the computer. In the embodiment shown, ADB data is received from the special ADB port of the Macintosh SE. The microcontroller includes read only memory, or ROM, that contains basic instructions for controlling the different elements of the power control circuitry. A microprocessor and random access memory, or RAM, is also present in the microcontroller to process the information received from ROM or from the computer.
Perhaps the most unique aspect of the power controller device is the ability to program any sequence of events once the computer is powered "on". Software that is sold in conjunction with the power controller device of the present invention allows a user to program a simulation of any number of keystrokes or input information to the computer's CPU. Additionally, this software can be used in conjunction with powerful macro programs to automate any number of computer procedures. For example, with the timer circuitry, the computer can automatically turn "on" and backup all data on a hard drive at a predetermined time every day. The entire data backup process can be automated so that one never need to attend the computer to keep their data securely backed up.
The embodiment shown was designed to work with the Macintosh SE personal computer because this computer includes a special "power on" key 21 that works effectively to power on a Macintosh II, but remains unused when connected to a Macintosh SE. The present invention is an improvement on the use of this key because not only does the power controller device allow the key to power on the computer, but it also includes conventional power controller features, allows peripheral devices to power up with the computer, and allows the power on feature to be programmed at a specific time or remote location.
The power controller device could work under other conditions too, allowing desktop power control through any input device for any computer system. For example, many computer systems include a mouse, such as the one shown in FIG. 4, as an input device. The power controller device could be programmed to respond to the pressing of the mouse button to power on a Macintosh or IBM-compatible computer. Another modification to the device would be to substitute the modem 23 of FIG. 4 with a FAX-type modem. This would alleviate the need to carry a large amount of information for people who work on the road. They only need to call up the host computer through the modem and subsequently send any information on the host computer to anyone with a FAX machine.
A further modification to the power controller device of the present invention would be to have individual relays on each electrical connector as shown in FIG. 7 (numbered 4 in FIGS. 1-3). By having individual relays, each connector could be programmed to be automatically switched, always "on", or manually switched on. The selective "on-off" condition of each connector would have additional applications for the power controller device. For example, the modem 23 in FIG. 4 would need to be always "on" in order to work as a remote switch for the computer. Therefore, it needs power from a separate AC power source or from an internal battery. By modifying the power controller device for selective "on-off" programming, the modem could be connected to the power controller device and its connector can be pre-programmed to be always "on". By connecting the modem to such a modified power controller device the modem would also be protected from overloads, surges, and noise.
The power control device of the present invention is a unique and useful device for many different applications in personal computing. In the early days of microcomputing the applications of these types of computers were quite limited. But today, the many and varied applications of microcomputers has brought about the need for a more useful power control device than conventional power strips.
In addition to its functional aspects there arc several physical aspects of the device that make it truly unique. The device is small in size, noiseless in its operation and can be positioned at a remote location far from the computer. Additionally, the device uses only one additional cable than conventional power strips and with the T-connector, the additional cable doesn't take up any additional ports on the computer. Its ease of installation is unique for this type of device. Finally, the use of this device saves on the wear and tear of power switches of the computer and peripheral devices. Since no manual switches need to be operated on any of the computer devices nor on the power controller device, no costly repairs of manual switches are needed with long term use of the device.
It should be apparent that many modifications could be made to the power controller device which would still be encompassed within the spirit of the present invention. It is intended that all such modifications may fall within the scope of the appended claims. | A power control device which incorporates a microcontroller to control the switching of power of a plurality of outlets. A host computer communicates with the microcontroller through the computer's keyboard interface to instruct the device to turn on or off one or more of the outlets either immediately or at one or more preset future times. An operator communicates with the microcontroller through the computer's keyboard intercede to instruct the device to initiate a sequence of pro-programmed on/off events. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority from U.S. Provisional Patent Application Ser. No. 61/164,311 filed Mar. 27, 2009, the contents of which are incorporated herein by reference in their entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
FIELD OF THE INVENTION
[0003] The present invention relates to insulated containers of the type popularly known as coolers, and more particularly to a cooler featuring built-in illumination.
BACKGROUND OF THE INVENTION
[0004] Coolers have become popular devices for storing and carrying foods, beverages, and other substances which must be maintained at temperatures which may be below ambient temperatures. One widespread use for coolers is to contain foods and beverages for outdoor activities such as picnics and camping. Such activities may last into the night. When daylight fades, visibility becomes a problem which affects both retrieval of objects from coolers and also performing tasks which may be either related or unrelated to objects retrieved from coolers.
SUMMARY OF THE INVENTION
[0005] The present invention addresses the above stated problems by providing illumination within portable coolers. Illumination may be provided for revealing contents of the cooler, which may include contents supported on trays and the like which may be part of a cooler, and also for illuminating the immediate vicinity of the cooler. At night, it may become difficult to identify contents of a cooler, such as discriminating among different types of beverage cans. As regards the immediate vicinity of the cooler, illumination in dark conditions, such as at night, may solve a problem which may exist in darkened surroundings such as the interiors of wheeled vehicles, buildings, and tunnels, among others, which may not be provided with sufficient illumination to discern contents of a cooler.
[0006] Also, tasks which may or may not be related to a cooler may be aided by supplementary light sources provided by the cooler. For example, bait stored for fishing activities may require preparation and mounting on fishing hooks. It would be highly convenient to have illumination for a cooler used for fishing purposes, so that selection, cutting, mounting of bait and related tasks may be conducted under conditions of ambient darkness in close proximity to the stored bait.
[0007] Further uses for illumination of coolers include identification and location of the user. Lighting may be used to identify a particular cooler or the location of the cooler and the person using that cooler.
[0008] In still another use, lighting may pertain to personal expression. Illumination may express personal sentiments such as affiliations with organizations. For example, a cooler brought to the scene of a sports event may be caused to emit light of colors associated with one of the teams performing in the event.
[0009] The present invention provides implementation of at least one purpose for illumination capability in a portable cooler.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Various features and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
[0011] FIG. 1 is a perspective view of an illuminated cooler according to at least one aspect of the invention.
[0012] FIG. 2 is a perspective view of FIG. 1 , but taken from the opposite side, and shown with a tray extending from the illuminated cooler.
[0013] FIG. 3 is a detail view of a part of a tray such as the tray of FIG. 2 , showing a container retention feature which has been omitted from FIG. 2 for clarity of the view.
[0014] FIG. 4 is a diagrammatic representation of an electrical circuit which may be provided in an illuminated cooler according to further aspects of the invention.
[0015] FIG. 5 is a perspective detail view of the tray of FIG. 2 .
[0016] FIG. 6 is a top plan view of the cooler of FIG. 1 , additionally showing lighting elements not shown in FIG. 1 .
[0017] FIG. 7 is a perspective view of an illuminated cooler according to another aspect of the invention.
[0018] FIG. 8 is a diagrammatic representation of an electrical circuit which introduces flashing to at least one light of an illuminated cooler according to at least one further aspect of the invention.
[0019] FIG. 9 is a diagrammatic representation of an electrical circuit which introduces different colors to at least some lights of an illuminated cooler according to at least one further aspect of the invention.
[0020] FIG. 10 is a side cross sectional view of an illuminated cooler according to a still further aspect of the invention.
[0021] FIGS. 11A-C show a table of reference numerals used in the Detailed description of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] FIG. 1 shows an illuminated cooler 100 which may comprise a receptacle 120 having an exterior surface 140 , an interior surface 160 , and a general storage chamber 180 defined within the interior surface 160 . The receptacle 120 may further comprise a lateral wall 200 defining a first open end and an opposed second end. In the position of normal use, and as depicted in FIG. 1 , the open end is the upper end, and is open to afford access to contents of the cooler 100 . The second end is the lower end, which is closed by a bottom wall 220 which spans at least some sections of the lateral wall 200 so as to substantially close the second or bottom end. A lid or closure 240 may be hinged or otherwise movably secured to the lateral wall 200 so as to removably engage the lateral wall 200 at the first open end.
[0023] The receptacle 120 is substantially insulated in any suitable way. As employed herein, the term “insulated” will be understood to mean that any component of the cooler 100 which is described as insulated comprises a constituent material known to retard transmission of heat therethrough, or alternatively, comprises an arrangement of materials known to retard transmission of heat. For example, closed cell polymeric materials used conventionally to insulate coolers, refrigerators, freezers, and the like may serve as insulation material. Examples of materials which themselves may not be insulating in nature but which may be formed or arranged to be insulating include glass, which as a solid may be heat transmissive, but when formed for example as fiberglass becomes insulating in nature. Other substances in fiber form may be regarded as insulating. Another example is polymeric materials which are formed to enclose voids, such as so-called bubble wrap, which comprises sheets of plastic arranged to contain voids or to contain pockets of air or other gasses. Void containing assemblies may be partially evacuated to produce vacuum or partial vacuum. Both insulated and non-insulated portions of the receptacle 120 may comprise a non-pourous, liquid impermeable resin capable of being injection molded for example.
[0024] The cooler 100 may comprise a tray 260 which is movable between a stowed position ( FIG. 1 ) and a deployed position ( FIG. 2 ). In the stowed position, the tray 260 may be held compactly to the receptacle 120 . As depicted in FIG. 1 , the tray 260 may be received within a recess formed within the lateral wall 200 so as to be substantially flush with the lateral wall 200 in the stowed position. In the deployed position, the tray 260 projects from the receptacle 120 so as to present a horizontal support surface.
[0025] The cooler 100 may comprise a plurality of wheels 280 which are rotatably fixed thereto and one or more handles 300 . The handles 300 may be hinged to swing to an exposed position, as shown in FIG. 2 , may be slidably mounted within the cooler to move to a deployed position corresponding to the exposed position shown in FIG. 2 , may comprise grips or recesses molded or otherwise formed in the cooler 100 , or may be disposed in any other suitable way.
[0026] Referring to FIG. 3 , the tray 260 may comprise openings 320 for receiving containers such as cups, cans, glasses and the like (none shown). Each opening 320 may be provided with a generally U-shaped wire 340 or the like which may be pivotally mounted in gimbal fashion within the tray 260 to swing down from its associated opening 320 to serve as a floor or equivalent interfering member which prevents a cup, can, or glass from falling through the opening 320 when the tray 260 is in the deployed position of FIG. 2 .
[0027] The cooler 100 comprises an illumination source which further comprise one or more individual lighting elements. For purposes of description of the present invention, a lighting element is any element having sufficient structure to emit light on its own. Lighting elements may comprise incandescent lamps, neon lamps, fluorescent lamps, light emitting diodes, electric arc electrodes, electroluminescent substances, and others. In any and all of its forms, the illumination source is supportably engaged with the receptacle 120 and is disposed to project light from the receptacle 120 . The illumination source may comprise, in addition to at least one lighting element, circuitry disposed to conduct electrical power to each lighting element where the latter is of the type using electrical power, and a switch disposed to control electrical power supplied to at least one lighting element.
[0028] An exemplary circuit arrangement for powering and controlling individual lighting elements 360 , 380 , 400 is described with reference to FIG. 4 . It should be understood that the circuit arrangement of FIG. 4 is shown only in representative capacity, and may be modified to accommodate any desired variation. For example, although the three individual lighting elements 360 , 380 , 400 are shown in FIG. 4 , fewer or more lighting elements may be accommodated. Connection logic and switching may be varied from FIG. 4 as desired.
[0029] An electrical storage device such as a battery 420 may provide electrical power which is distributed by circuitry 440 . As employed herein, the term “circuitry” will be understood to encompass all individual conductors, electrical insulation, connections, and auxiliary devices required to accomplish the described functions regardless of whether such items are explicitly shown or described. Also, the term “battery” is used only in a representative sense and will be understood to encompass single electrochemical cells, plural electrochemical cells, capacitors, supercapacitors, and other electrical storage devices in any combination. It would also be possible to omit an electrical storage device for example by providing a cooler such as the cooler 100 with a plug and cord assembly (not shown) or with a receptacle for receiving an extension cord or the like. The battery 420 and the circuitry 440 may be carried aboard the receptacle 120 , for example being supported within the lateral wall 200 , the closure 240 , and other structure of the receptacle 120 where necessary.
[0030] The circuitry 440 may comprise a manual master switch 460 disposed to control all of the lighting elements 360 , 380 , 400 , as well as individual switches 480 , 500 , 520 arranged to control only one lighting element, such as the lighting elements 360 , 380 , 400 . Switches such as the switches 460 , 480 , 500 , 520 may be located at any convenient exterior location on the receptacle 120 . Switches may utilize exposed operators such as toggles, axially moved knobs, rotary dials, or operators which are covered by a liquid resistant switch cover such as an elastomeric sheet and which may be actuated for example by pressing on the liquid resistant sheet. These are known switch control arrangements and need not be further detailed herein.
[0031] Referring now to FIG. 2 , the illumination source may comprise a tray illuminator 540 which is disposed to project light directly onto the tray 560 so as to illuminate objects (not shown) placed on the tray 560 . The tray 560 may be functionally and structurally similar to the tray 260 , for example.
[0032] Referring also to FIG. 6 , the illumination source may also comprise additional lighting elements which may include for example, first lighting elements or receptacle illuminators 580 located on the underside of the closure 240 and which are disposed to project light into the general storage chamber 180 . In the absence of contents within the general storage chamber 180 , light from the receptacle illuminators 580 would project light against the interior surface 160 of the receptacle 120 . A second lighting element may be disposed to project light outside the general storage chamber 180 . The second lighting element may be for example the tray illuminator 540 , or may comprise an environment illuminator 600 disposed to project light proximate the receptacle 120 , near the receptacle 120 yet not directly onto a tray such as the tray 260 . The environment illuminator 600 may be focussed such that light projected therefrom, indicated as broken lines 620 , passes over the tray 260 to project away from the receptacle 120 , thereby illuminating the area proximate the cooler 100 .
[0033] The circuitry 440 (see FIG. 4 ) may be modified such that a switch such as one of the switches 480 , 500 or 520 may serve as an environmental illuminator switch disposed to control only the environmental illuminator 600 .
[0034] FIG. 5 shows an arrangement wherein a tray 640 is at least partially translucent in a direction extending away from an associated receptacle 660 when the tray 640 is in the deployed position. Other than being translucent, the tray 640 may be for example a structural and functional equivalent of the tray 260 . Similarly, the receptacle 660 may be the structural and functional equivalent of the receptacle 120 . In the arrangement of FIG. 5 , the illumination source may further comprise a tray accent illuminator disposed to project light through the tray 640 in a direction away from the receptacle 660 . The tray accent illuminator may comprise one or more lighting elements 680 which are disposed to project light through the tray 640 in a direction away from the receptacle 660 , as indicated by broken lines 700 .
[0035] The circuitry 440 (see FIG. 4 ) may be modified such that a switch such as one of the switches 480 , 500 or 520 may serve as a tray accent illuminator switch disposed to control only the lighting elements 680 of the tray accent illuminator.
[0036] FIG. 7 shows a cooler 720 which comprises an illuminator stand 740 which is movable between a stowed position and a deployed position. In the stowed position, the illuminator stand 740 may be held compactly to the receptacle 760 . For example, the illuminator stand 740 may be slidably received within the receptacle 760 so that it can be retracted substantially thereinto. The illuminator stand 740 , shown in the deployed position in FIG. 7 , may have a proximal end which is movably mounted to the receptacle 760 . For example, the proximal end, which may bear at lest one lighting element 800 , can be manually moved vertically, as indicated by the arrow 780 , so as to be movable to project outside the receptacle 760 in the deployed position.
[0037] The circuitry 440 (see FIG. 4 ) may be modified such that a switch such as one of the switches 480 , 500 or 520 may serve as an illuminator stand switch disposed to control only the lighting element 800 of the illuminator stand 740 .
[0038] FIG. 8 shows an arrangement wherein a flasher 820 has been incorporated into circuitry 840 serving lighting elements 860 which may be incorporated into a cooler (not shown) such as the cooler 100 . Each lighting element 860 may be controlled by an individually dedicated set 880 of normally open contacts which may be integral with or controlled by the flasher 820 . The flasher 820 may be an electronic relay or any other device or devices which individually or collectively cause the circuitry 840 to provide power to and illuminate the lighting elements 860 automatically and intermittently.
[0039] The flasher 820 may comprise a manual controller 900 which initiates and terminates flashing of the lighting elements 860 . The manual controller 900 may comprise a switch for manually switching power to the flasher 820 , or may be an indirect controller such as a keypad where for example the flasher 820 comprises a programmable or programmed controller. A programmable controller will be understood to comprise a controller wherein the output or control sequence produced thereby may be arranged for subsequent implementation by a person using the programmable controller. A programmed controller will be understood to comprise a predetermined output or control sequence which may be initiated but not modified by a person using the programmed controller.
[0040] As employed herein, terms such as “flasher” and “flashing” do not necessarily imply a regular sequence. Both the time interval during which any light or lamp such as the lighting elements 860 may be illuminated and the time interval during which any light or lamp may be extinguished may be varied according to a regular sequence or an irregular sequence. For example, where many lamps are provided, certain lamps may be selectively illuminated to form letters, symbols and words. Words and other illuminated entities may be subjected to selective illumination and extinguishing such that, for example, the word or other illuminated entities appear to travel along the matrix of lamps. This may be referred to as a scrolling message (not shown). Programmed and programmable controllers for producing scrolling messages are known. The lighting elements 860 may be illuminated in tandem or may be staggered.
[0041] The circuitry 840 may be integrated with circuitry such as the circuitry 440 of FIG. 4 .
[0042] The circuitry 840 may be modified to include a master switch 920 arranged to control power to the flasher 820 and lighting elements 860 flashably controlled thereby.
[0043] FIG. 9 shows an arrangement wherein an illumination source may comprise lighting elements 940 , 960 , 980 , 1000 of different colors, which may be incorporated into a cooler (not shown) such as the cooler 100 . Each of the lighting elements 940 , 960 , 980 , 1000 may take one of the colors red, green, blue, and yellow for example. The illumination source of FIG. 9 is disposed to project light selectively of different colors from the receptacle (not shown) of the cooler with which the lighting elements 940 , 960 , 980 , 1000 may be associated.
[0044] A lighting actuator 1020 may be disposed to illuminate the lighting elements selectively according to color. The lighting actuator 1020 may be a programmable controller or a programmed controller of the type described with regard to the flasher 820 of FIG. 8 for example. Such a programmable controller or programmed controller may have sets 1040 of normally open contacts which close supply circuitry 1060 to the lighting elements 940 , 960 , 980 , 1000 . Of course, manual switches (not shown) may be provided in place of the lighting actuator 1020 to enable a person to illuminate the lighting elements 940 , 960 , 980 , 1000 manually in place of an automated controller such as the flasher 820 if desired.
[0045] The circuitry 1060 may be integrated with circuitry such as the circuitry 440 of FIG. 4 .
[0046] The circuitry 1060 may be modified to include a master switch 1080 arranged to control power to the lighting actuator 1020 and lighting elements 940 , 960 , 980 , 1000 .
[0047] FIG. 10 shows an illuminated cooler 1100 which may comprise a dry cover storage compartment 1120 for storing articles (not shown) according to a further aspect of the invention. The illuminated cooler 1100 in other respects may be the functional and structural equivalent of an illuminated cooler such as the illuminated cooler 100 of FIG. 1 . Therefore, electrical details such as those pertaining to illumination will be omitted from the description of the illuminated cooler 1100 , it being understood that any illumination scheme according to the present invention may be incorporated thereinto.
[0048] The illuminated cooler 1100 may comprise a receptacle 1140 having a lateral wall 1160 and a closure 1180 . The closure 1180 may have a cavity which establishes the dry storage compartment 1120 which is separate from yet in communication with the general storage chamber 1200 of the receptacle 1140 . Articles (not shown) contained within the cover storage compartment 1120 may be subjected to temperatures prevailing within the general storage chamber 1200 yet isolated from contact with contents thereof. A cooling influence prevailing within the general storage chamber 1200 may be communicated to the dry storage compartment 1120 through slots 1220 , 1240 which may be formed in a door 1260 . The door 1260 may be pivotally mounted to a wall 1280 formed in the closure 1180 to define the dry storage compartment 1120 . Pivotal mounting may be provided by a hinge 1300 for example such that the door 1260 may pivot or swing as indicated by the arrow 1320 . The door 1260 may engage the closure 1180 by frictional engagement of a bump or projection 1340 .
[0049] The door 1260 may if desired be fully removable from the closure 1180 , or may alternatively be mounted to the closure 1180 or open relative to the closure 1180 in ways other than that shown and described herein. It will be appreciated that the dry storage compartment 1120 may be incorporated into the closure such as the closure 1180 of an illuminated cooler according to any aspect of the present invention.
[0050] Although discussion herein is generally directed to maintaining foods and other substances at temperatures below ambient temperatures, it will be appreciated that a cooler according to the present invention may be thought of as an insulated receptacle which may be employed if desired to maintain foods and other substances at temperatures above ambient temperatures. | An electrically illuminated cooler having a temperature insulated general storage chamber and at least one illumination source. The illumination source may comprise a single lighting element such as for example a light emitting diode, which may flash, or a plurality of lighting elements which may be directed to different areas, which may be of different colors, and which may be independently controlled. The cooler may comprise circuitry including switches, flasher, and power storage such as battery cells. The cooler may comprise a fold out tray which itself may be illuminated by the illumination source, or may alternatively or in addition may be internally illuminated. The cover of the cooler may have a compartment which communicates with the general storage chamber but which stores articles out of contact with contents of the general storage chamber. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Application Ser. No. 61/051,929, filed May 9, 2008, the entire disclosure of which is incorporated by reference herein.
BACKGROUND
Chemical vapor deposition grown diamonds can be difficult to distinguish from mined diamonds using conventional techniques. Detection of CVD diamond is of importance to the diamond industry to prevent the fraudulent sale of CVD diamond as natural diamond, and to enable the detection of CVD diamond for the purpose of ensuring that there is no misrepresenting natural as CVD diamond. Further, the detection of CVD diamond may be useful for protecting intellectual property rights.
The detection of CVD diamond is difficult and laborious due to the fact that multiple instruments are needed. Such instruments are used to first determine that the diamond in question is a type II A. Colorless cvd diamonds currently are type II A which indicates a very low nitrogen level. The instruments are then used for testing for the presence of N-V centers, which are a substitutional nitrogen atom adjacent to a carbon vacancy. Finally, instruments are used to microscopically view diamonds for features such as strain. All of these tests are required to raise the certainty that a diamond is natural or cvd. None of these tests are complete in themselves, as the presence of N-V centers is rare in natural diamonds, but does occur. Such N-V centers fluoresce at red-orange wavelengths due to it's two main emission peaks centered at 575 and 637 nm. The purer the diamond the weaker the fluorescence. The fluorescence can also be seen by illuminating the diamond with short wavelength ultraviolet light in an expensive instrument such as the “Diamond View”. The detection process is long and difficult for large pure stones and nearly impossible for small stones.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a system for detecting CVD grown diamonds in a retail setting according to an example embodiment.
FIG. 2 is a graph illustrating photo luminescence (PL) of white, brown and pink cvd diamonds.
FIG. 3 is a block diagram of an alternative system for detecting CVD grown diamonds in a retail setting according to an example embodiment.
FIG. 4 is a cross section representation of combined fibers according to an example embodiment.
DETAILED DESCRIPTION
In the following description, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific embodiments which may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural, logical and electrical changes may be made without departing from the scope of the present invention. The following description of example embodiments is, therefore, not to be taken in a limited sense, and the scope of the present invention is defined by the appended claims.
A system 100 in FIG. 1 may be used to detect CVD grown diamond. System 100 may be formed in a size that is compatible for deployment in a jewelry retail store and be operated by relatively unskilled personnel. System 100 may utilize the presence of an N-V center in a CVD grown diamond. At 110 , a radiation source provides short wavelength light. The short wavelength light may be provided by a green or blue laser, such as a commercially available semiconductor laser which emits at 405 or 532 nm. Many other wavelengths may be used that cause fluorescence of diamonds with N-V centers, such as wavelengths in the 400 to 550 nm range, and may include portions of the UV range of 10 to 400 nm, or at least the upper portions of the UV range. Other sources that provide suitable wavelength light may also be used.
A fiber optic delivery system or lens 120 may be used to provide short wavelength radiation to a holder 125 to position a table of a gemstone 130 at a predetermined distance from the light. The holder 125 may be adapted with suitable fixtures such as clamps or platforms with indentations to hold a loose gemstone or gemstones, as well as a piece of jewelry containing one or more gemstones such as diamonds. The laser in one embodiment is highly focused on the crystal surface of the gemstone. A filter(s) (or spectrometer) 140 may be used to separate the laser light from the PL light (photo-luminescence).
The presence of N-V centers would result in emission bands centered at about 575 and/or 637 nm, and the filters can be used to allow detection of these wavelengths. A detector 150 may be positioned to receive and detect the PL light. In one embodiment, a thermoelectric cooler 160 may be used to cool the gemstone. The cooler 160 may be integrated with the holder 120 in one embodiment. Alternatively to a thermoelectric cooler, a cooling media such as liquid nitrogen or dry ice may be positioned proximate to the gemstone to cool the gemstone.
Detector 150 may contain suitable electronics and metering to indicate the nature and type of the diamond from the detected PL light. Detector 150 may be used in conjunction with microscopic examination to confirm the natural or CVD origins of the gemstone. Further filtering of wavelengths may also be used to detect treated natural stones or high pressure high temperature created stones. In a further embodiment, handling of the stones may be automated so that they could be continuously measured and recorded without human handling.
In further embodiments, filters or an inexpensive spectrometer may be used to separate wavelengths to ensure that the laser light and the PL light are separated. A suitable covering may be used to eliminate stray room light from entering the detector and laser light from straying to the outside. Safety interlocks may be provided to shut down the laser in the event the cover is removed. Holder 125 may be made large enough to hold several sizes of stones. Control circuitry and sensors may be included to indicate a pass, fail, or further inspection notice for the tester.
FIG. 2 is a graph illustrating photo luminescence (PL) of white, brown and pink cvd diamonds.
Some embodiments may be made fairly inexpensive and have a fairly small footprint, and may be easy to operate, making them suitable for use and operation by a store clerk in a retail store.
FIG. 3 is an alternative system 300 may be used to detect CVD grown diamond. System 300 may be formed in a size that is compatible for deployment in a jewelry retail store and be operated by relatively unskilled personnel. System 300 may utilize the presence of an N-V center in a CVD grown diamond. At 310 , a light source provides short wavelength light to an optical fiber 315 that may be optimized to transmit the short wavelength light. The short wavelength light may be provided by a green or blue laser, such as a commercially available semiconductor laser which emits at 405 or 532 nm. Many other wavelengths may be used that cause fluorescence of diamonds with N-V centers, such as wavelengths in the 400 to 550 nm range, and may include portions of the UV range of 10 to 400 nm, or at least the upper portions of the UV range. Other sources that provide suitable wavelength light may also be used.
The optical fiber 315 provides the light from light source 310 to a sample holder 320 to position a table of a gemstone at a predetermined distance from the light. The sample holder 320 may be adapted with suitable fixtures such as clamps or platforms with indentations to hold a loose gemstone or gemstones, as well as a piece of jewelry containing one or more gemstones such as diamonds. The light from light source 310 in one embodiment is highly focused on the crystal surface of the gemstone.
In one embodiment, CVD diamonds will fluoresce, producing a PL light. This produced light is returned back to the optical fiber 315 , which branches into a second type of fiber 325 optimized to transmit wavelengths corresponding to the PL light.
The presence of N-V centers would result in emission bands centered at about 575 and/or 637 nm, and the second type of fiber 325 may be used to carry such emissions to a spectrometer 330 to perform detection of these wavelengths. The fibers 315 and 325 diverge at a junction 335 such that each may carry it corresponding light independently of the other.
In one embodiment, a thermoelectric cooler may be used to cool the gemstone. The cooler may be integrated with the holder 320 in one embodiment. The spectrometer 330 may contain suitable electronics and metering to indicate the nature and type of the diamond from the detected PL light. In some embodiments, the spectrometer 330 may be used in conjunction with microscopic examination to confirm the natural or CVD origins of the gemstone. Further filtering of wavelengths may also be used to detect treated natural stones or high pressure high temperature created stones. In a further embodiment, handling of the stones may be automated so that they could be continuously measured and recorded without human handling.
In further embodiments, a light splitter may be used at 335 to separate wavelengths in fibers 315 and 325 to ensure that the light from light source 310 and the PL light from the diamond fluorescence are separated. In one embodiment, the components are mounted on a substrate, such as a board or other supportive material, and a suitable covering may be used to eliminate stray room light from entering the system, and keep laser light from straying to the outside. Safety interlocks may be provided to shut down the light source in the event the cover is removed. Holder 320 may be made large enough to hold several sizes of stones. Control circuitry and sensors may be included to indicate a pass, fail, or further inspection notice for the tester.
FIG. 4 is a cross section representation of combined fibers 315 and 325 from FIG. 3 represented generally at 400 . In one embodiment, fiber 315 is represented as a single fiber at 410 , surrounded by multiple fibers 325 , as represented with reference number 420 . This cross section illustrates the combined fibers taken along lines 4 - 4 in FIG. 3 . The fibers are then separated at junction 335 to provide independent paths for the generated and emitted light.
The Abstract is provided to comply with 37 C.F.R. §1.72(b) to allow the reader to quickly ascertain the nature and gist of the technical disclosure. The Abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | A system includes a radiation source to provide short wavelength light. A holder positions a table of a gemstone to receive the light. A detector is positioned to receive fluorescent light from the gemstone when the gemstone is a CVD grown gemstone. | 6 |
COPYRIGHT STATEMENT
A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the U.S. Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE INVENTION
This invention relates to connectors for cables conducting electromagnetic waves generally and more specifically to connectors, plugs, and sockets for audiovisual and other electronic equipment having interchangeable components.
When using cables or wires to connect such things as sound amplification or video equipment, it is sometimes desirable to change the terminating plug or socket on one or both ends of a cable, or to change the type, color, or other feature of the shell which covers and protects the ends of the cable. Since it is usually desirable to solder or tightly crimp the ends of the conductors of a cable to the terminating plug or socket, and since the cover or shell is usually placed on the cable before such soldering or crimping, it is difficult to change either the terminator or the shell of a cable which has already been made up.
SUMMARY OF THE INVENTION
The Interchangeable Connector System overcomes the problem of a lack of interchangeability among terminating plugs and sockets and shells or covers by providing a system of interchangeable Terminators and Shells which can be mounted or changed after the soldering or crimping of the conductors of a cable to a Common Connector Body. The Shells and Terminators can be mounted or changed without having to remove the cable from the Common Connector Body, thus providing a very flexible and reusable system.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows an exploded overview in perspective of an Interchangeable Connector System according to the present invention.
FIG. 2 shows an exploded perspective view of one configuration of the system of FIG. 1 .
FIG. 3 shows a section view of the system of FIG. 2 .
FIG. 4 shows a longitudinal cross-sectional view of an assembled Interchangeable Connector System according to the present invention.
FIG. 5 shows a perspective view of a Common Connector Body coupled to a shielded cable.
FIG. 6 shows a cutaway view of a Shell during assembly onto the Common Connector Body after the Common Connector Body has been coupled to a cable.
FIG. 7 shows a cutaway view of a Shell assembled onto the Common Connector Body of FIG. 6 .
FIG. 8 shows an exploded perspective view of a Terminator during assembly with the Shell and the Common Connector Body of FIG. 7 .
FIG. 9 shows a perspective view of a variety of assembled Interchangeable Connector Systems according to the present invention.
FIG. 10 shows an overview in elevation of an alternative embodiment of the Interchangeable Connector System according to the present invention.
FIG. 11 shows a section view of two assembled Interchangeable Connector Systems of the alternative embodiment of FIG. 10 .
DETAILED DESCRIPTION
This invention, an Interchangeable Connector System, shown in overview in FIG. 1, provides for the interchangeable assembly of a variety of Terminators 300 and Shells 200 onto a Common Connector Body 100 . In an alternative embodiment, shown in overview in FIG. 10, the Interchangeable Connector System provides for the interchangeable assembly of a variety of Terminators 300 onto a Common Connector Body 100 to which a Shell has been molded, creating a Common Connector Body with Molded Shell 500 .
In the system of this invention, the Common Connector Body 100 is fixedly coupled to a cable 400 which conducts electromagnetic waves. The cable could be an audio or video cable which conducts electrical signals, or a fiber-optic cable which conducts modulated light, or it could be another type of cable conducting an electromagnetic wave. The fixed coupling of the cable to the Common Connector Body could be by a number of means, including soldering, crimping, or welding for an electrically conductive cable and gluing for an optically conductive cable. Clamping is another means of fixedly coupling a cable to the Common Connector Body. The coupling of the cable to the Common Connector Body is considered to be fixed because in practice it is desirable not to undo the coupling even if it is possible to do so, for instance by desoldering. A feature of the present invention is that an uncoupling of the cable 400 from the Common Connector Body 100 is not necessary in order to change Terminators 300 or, in an embodiment, Shells 200 .
In contrast to the fixed coupling of the Common Connector Body 100 to the cable 400 , the Terminators 300 and, in an embodiment, the Shells 200 are removably mounted and interchangeably mounted on the Common Connector Body 100 . As will be further shown, the present invention provides Terminators 300 and, in an embodiment, Shells 400 which can be mounted on the Common Connector Body 100 after the Common Connector Body 100 has been fixedly coupled to the cable 400 , and which can be removed and replaced with another Terminator 300 or Shell 200 without having to uncouple the Common Connector Body 100 from the cable 400 . A preferred embodiment of this invention provides a method of mounting the Terminators 300 and Shells 200 on the Common Connector Body 100 by a means such as a threaded area, a bayonet mount, or some similar, removable means. Mounting the Terminators and Shells in such an easily removable way provides a system having great flexibility for being changed and reconfigured without special tools.
An embodiment of the present invention, with an electrically conductive cable having one conductor and a shield, with the connection terminating in a -inch phone plug, is illustrated and described. The practice of this invention for other types of terminators, for multiple-conductor cables, and for optically conductive terminators and cables, is described in this document.
Referring now to FIGS. 2, 3 , & 5 , the Common Connector Body 100 is designed to be coupled to a cable 400 by soldering, crimping, or other suitable attachment. The coupling to a conductor or conductors of a cable can be supplemented by a mechanical coupling to provide strain relief. In a single-conductor embodiment, as shown in FIG. 3, the conductor 410 of a cable 400 is electrically coupled to a cable contact point 110 of the Common Connector Body. The shield 420 of the cable is electrically coupled to the main body 120 of the Common Connector Body, either directly or by attachment to a strain relief 130 or strain relief tabs 135 where the strain relief and strain relief tabs are electrically connected to the main body. The cable contact point 110 conducts an electrical signal to a contact receptacle 160 . The electrical path from the cable contact point to the contact receptacle is electrically insulated from the main body 120 . One way to achieve this insulation is with an insulator 170 . The cable 400 may be further mechanically secured to the strain relief 130 and strain relief tabs 135 . In an embodiment with more than one conductor, the cable contact point 110 and the contact receptacle 160 are divided into more than one electrically insulated paths.
In order to protect the coupling points of the cable 400 to the Common Connector Body 100 and to complete the overall integrity of the connection, a Shell 200 may be interchangeably mounted on the Common Connector Body as shown in FIGS. 6 & 7. Alternatively, a Shell may be molded to the Common Connector Body 100 creating a Common Connector Body with Molded Shell 500 , as shown in FIGS. 10 & 11.
The interchangeable Shell 200 may be of a color or texture or shape or can incorporate a design feature that differentiates the assembled connector from others. The Shells 200 are easily interchangeable because they can be mounted over the Common Connector Body 100 while the cable 400 remains coupled. Therefore the Shell on a cable can be changed for one of a different appearance or feel in order to identify, for instance, a different use or point of connection for the cable.
The Shell 200 is placed over and coupled to the Common Connector Body 100 . In a preferred embodiment, a larger threaded portion 140 of the Common Connector Body engages a threaded portion 240 of the Shell. Alternatively, the attachment of the Shell to the Common Connector Body could be achieved with a bayonet mount or another type of mount. FIG. 7 shows the Shell 200 mounted on the Common Connector Body 100 .
A Terminator 300 is interchangeably coupled to the Common Connector Body 100 . In one embodiment, the Common Connector Body 100 is fitted with an interchangeable Shell 200 . In an alternative embodiment, a Shell has been molded to the Common Connector Body 500 . The Terminator 300 will normally be a plug, but could be a socket, a spade lug, a switch, or an indicator light. As shown in FIG. 10, the Terminator can be a single assembly, or can be an assembly which attaches to the Common Connector Body using a separate collet 390 . As shown in FIGS. 10 & 11, a ring 600 or washer of rubber, plastic, or other material can optionally be mounted between the Terminator 300 and the Common Connector Body 100 .
The specific configuration of a Terminator may vary depending on the nature of the Terminator. A single-conductor ¼ inch plug, for instance, will have a tip portion 310 and a ring portion 320 (FIGS. 2 & 3 ). The tip portion 310 conducts an electrical signal to the contact pin 360 , which is adapted to fit into and make electrical contact with the contact receptacle 160 of the Common Connector Body. The ring portion 320 conducts an electrical signal to the threaded portion 350 of the Terminator, which is adapted to attach to, and make electrical contact with, the smaller threaded portion 150 of the Common Connector Body.
Portions corresponding to the tip and ring portions of the ¼ inch plug will exist in other types of plugs, in sockets, and in the other types of Terminators in this system. FIG. 11 shows the corresponding tip 310 and ring 320 portions of an RCA-type or co-axial plug. In a system with more than one conductor, there will be more than two portions of the Terminator. For example, in a stereo plug, there will be three electrically separate portions.
In a preferred embodiment, a smaller threaded portion 150 of the Common Connector Body engages a threaded portion 350 of the Terminator in order to mechanically attach the Terminator 300 to the Common Connector Body. This mechanical attachment also creates an electrical attachment between the main body 120 of the Common Connector Body 100 and a tip portion 310 of the Terminator. A ring portion 320 of the Terminator is electrically coupled through the contact pin 360 to the contact receptacle 160 . Since the contact receptacle 160 is electrically connected to the cable contact point 110 , which is electrically coupled to the conductor 410 of a cable, and the main body 120 is electrically coupled to the shield 420 or second conductor of the cable 400 , in the assembled connector system, the tip portion 310 is electrically coupled to the conductor 410 and the ring portion 320 is electrically coupled to the shield 420 or second conductor of the cable 400 .
In an embodiment having more than one conductor, the tip 310 and the corresponding contact pin 360 may be divided into more than one electrically insulated paths, adapted to make contact with a similarly divided contact receptacle 160 which in turn is electrically coupled to a divided contact point 110 or plural contact points.
The Terminators can be provided in a wide variety of connector types, including but not limited to straight and angled versions of, and both plug and socket versions of, ¼-inch phone connectors, mini-phone connectors, RCA or co-axial type connectors, photographic electronic flash connectors of the PC-type or other types, and banana connectors. The Terminators may also be provided as spade lugs.
With the Interchangeable Connector System, the Terminators and, in a preferred embodiment, the Shells can be removed and reassembled after the initial assembly of the cables, Shells, and Terminators. This interchangeability is possible without having to disconnect the cable from the Common Connector Body, and can therefore be done quickly, in the field, without the need for a soldering iron or other special tool. FIG. 9 shows some of the variety of Terminators and Shells which can be interchangeably assembled with this system.
In accordance with the principles of the present invention, a “Connector Body Means” is a mechanical element which provides 1) a coupling point or points upon which to couple the conductor or conductors of a cable, 2) a point or points upon which to removably mount a Terminator in such a way that the signal of the conductor or conductors of the cable is carried through to the Terminator Means, and, in an embodiment of the invention, 3) a surface upon which to removably mount a Shell Means. The mounting and removal of the Terminators and, in an embodiment, the Shells, may be done without having to uncouple the cable from the Connector Body Means. Examples of the preferred ways of coupling the conductors of a cable to the Connector Body Means are soldering and crimping for an electrically conductive cable and gluing for an optically conductive cable.
In accordance with the principles of the present invention, a “Terminator Means” is a mechanical element which may be removably mounted on the Connector Body Means in such a way that the signal of the conductor or conductors of the cable is carried through to the Terminator Means. The Terminator Means could be a plug, socket, indicator light, transformer, fuse holder, or other such element. The Terminator Means could be a combination, such as plug, indicator light, transformer, and fuse holder combination.
In accordance with the principles of the present invention, a “Shell Means” is a mechanical element which may be removably mounted on the Connector Body Means. The purpose of the Shell Means is partly structural, to protect the point of coupling of the cable to the Connector Body Means and to provide a gripping surface for the user of the system, and partly informative or decorative, since different properties of a Shell Means, such as color, texture, size, and shape may be used to differentiate terminated cables under this system.
In operation, a person using the Interchangeable Connector System might be setting up or making changes to an audiovisual system and need, for instance, to substitute a loudspeaker requiring a ¼-inch phone plug connector in place of a loudspeaker requiring an RCA-type plug. The person would unmount the RCA-type plug Terminator from the Common Connector Body of an already made-up cable and mount a ¼-inch phone plug Terminator in its place, thus changing the configuration of the cable without having to uncouple the cable from the Common Connector Body and without any special tools. The person might also exchange the Shell covering an end of a cable for a Shell of a different color, shape, or texture in order to indicate that the purpose of the cable had changed. This exchanging of Shells could be accomplished without uncoupling the cable from the Common Connector Body, and without any special tools.
Using this system, a provider of cables could offer various terminators and shells and separately offer lengths of cable with Common Connector Bodies securely coupled to both ends. The customers of such a provider of cables could then obtain the exact length and grade of cable desired, and separately obtain the exact Terminators and Shells desired. The customer could then assemble these components without special tools, and could change the configuration as needed.
While a preferred form of the invention has been described and shown in the drawings, since variations in the preferred form will be apparent to those skilled in the art, the invention should not be construed as limited to the specific form shown and described, but instead should be construed as set forth in the following claims. | An Interchangeable Connector System providing for the interchangeable removable installation of a variety of Terminators, such as plugs and sockets, and a variety of Shells or covers, to a Common Connector Body. The installation and removal of the Shells and Terminators is performed after the Common Connector Body is connected to the cable, and does not require the disconnection of the cable from the Common Connector Body. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is based on and hereby claims priority to International Application No. PCT/EP2007/050674 filed on Jan. 24, 2007, and German Application No. 06001745.6, filed on Jan. 27, 2006, the contents of both of which are herein incorporated by reference.
BACKGROUND
The embodiments discussed herein relate to a method for allocating at least one payload data connection to at least one multiplex connection which is provided between a first network element and a second network element.
For the purpose of transmitting voice data via a mobile communication system or mobile radio system, use is increasingly being made of packet-oriented data transmission methods in which, depending on the transmission protocol that is used in each case, data fields having different sizes are provided for transmitting the compressed voice data. Transmission protocols that are generally used include “Layer 2” transmission protocols such as e.g. the Ethernet protocol, as well as the Internet Protocol (IP), the “User Datagram Protocol” (UDP) (RFC 768), the “Realtime Transport Protocol” (RTP) (RFC 3550), and in many cases also the “Iu Framing Protocol” (IuFP) (3GPP TS 29.415).
For example, in the so-called CS domain of the “Core Network” of a third-generation mobile radio system (3GPP), a so-called “Nb” data connection is established for data transmission e.g. between a so-called Media Gateway unit (MGW) and/or a “Mobile Switching Center” (MSC). The voice or multimedia data to be transmitted is compressed, e.g. by an “Adaptive Multi-Rate” (AMR) voice encoding unit, and the compressed voice data is then transmitted via the “Iu Framing Protocol” (IuFP) (3GPP TS 29.415) or the RTP, UDP or IP protocol (cf. standard 3GPP TS 29.414).
The data fields of the relevant transmission protocols, i.e. the relevant “headers”, are together often significantly larger than the data, e.g. compressed voice data, which is transmitted therein. For example, the data field of an IP packet has a size of 20 bytes (IP Version 4.0) or 40 bytes (IP Version 6.0). The data fields of the UDP protocol have a size of 8 bytes, whereas the data fields of the RTP protocol comprise 16 bytes and those of the IuFP protocol comprise 4 bytes. By contrast, the data which is compressed by the AMR voice encoding unit has a size of 35 bytes in the “12.2 kHz” mode or a size of 5 bytes in the “Silence Indication” (SID) mode which is used between voice pauses.
A plurality of payload data connections, e.g. telephone connections, are usually transmitted concurrently between at least two Mobile Switching Centers or two Media Gateway units, e.g. in accordance with the standard for the so-called NB interface. In the same manner as the Nb interface, the data transmission can take place via the “Iu” interface which is likewise provided in a 3GPP mobile radio system and exists between a Media Gateway unit or a Mobile Switching Center and a so-called “Radio Network Controller” (RNC) unit (cf. 3GPP TS 25.414 and 25.415).
The currently existing standards provide for an individual physically separate data connection, this being realized in accordance with the relevant transmission protocol for an IP/UDP/RTP data connection, to be established via the Nb or Iu interface for each payload data connection that is to be transmitted, e.g. for a telephone call, and for the data packets, these being constructed in accordance with the relevant IP, UDP and RTP transmission protocol, to be transmitted via the data connection.
In the context of both the Nb interface and the Iu interface, the IP, UDP and RTP protocol is terminated in each case at the delimiting Media Gateway unit and the delimiting Mobile Switching Center or the delimiting RNC, i.e. the data fields of the individual data packets that are transmitted via the Nb or Iu data connection correspond to some extent at least and are read out and further processed in the cited units following the transmission. By contrast, the data fields of data packets that are realized in accordance with the IuFP protocol are routed through the relevant Media Gateway unit or Mobile Switching Center unchanged.
Furthermore, a multiplicity of multiplexing technologies, via which data of a plurality of payload data connections is transmitted almost simultaneously by a multiplexed data connection, are known in the field of transmission technology. Such data connections, being provided for the purpose of transmitting a plurality of payload data connections or telephone connections, are subsequently designated as multiplexed connections.
At the Nb or Iu interface, data of a plurality of payload data connections is advantageously transmitted together within a multiplexed connection which is preferably transported by the IP/UDP/RTP protocols. Data of a plurality of payload data connections, preferably with individual IuFP header and individual payload data such as e.g. compressed voice data in each case, could thus be contained in one IP packet which contains in each case only one IP, UDP and RTP header. As a result, the required bandwidth for the transport could be significantly reduced. This possibility is not yet described in the standard, however.
For the purpose of establishing a payload data connection via an Nb data connection, provision is made for the so-called “BICC IP Bearer Control Protocol” (IPBCP) (ITU-T Q.1970), which itself uses the so-called “Session Description Protocol” (SDP) (IETF RFC 2327) (cf. 3GPP TS 29.414). For the purpose of establishing a payload data connection between a first and second Media Gateway unit, the IPBCP protocol provides for the transmission of an “IPBCP Request Message” from the first to the second Media Gateway unit. This message is answered by the second Media Gateway unit by an “IPBCP Response Message”. Using the cited IPBCP messages, the first and second Media Gateway units exchange their respective IP addresses and UDP port numbers, knowledge of which is required for the exchange of data between the first and second Media Gateway units. The IPBCP messages are transmitted transparently by the so-called BICC signaling protocol (ITU-T Q.1902.1-5).
SUMMARY
The embodiments address the problem of specifying a method for allocating at least one payload data connection to a multiplexed connection which is provided between at least one first network element and at least one second network element, where the transmission bandwidth that is required for transmitting the payload data, e.g. voice data, is significantly reduced.
The essential point of the method can be considered to be that a first signaling message is generated by the first network element and transmitted to the second network element, wherein the readiness of the first network element to transport the at least one payload data connection via a multiplexed connection in each case is indicated to the second network element by the first signaling message. Depending on the indicated readiness of the first network element and on whether the transport of the at least one payload data connection via a multiplexed connection is supported by the second network element, the second network element either allocates each of the at least one payload data connections in each case to a multiplexed connection between the first network element and the second network element or selects a transport outside of a multiplexed connection for this payload data connection. Using a second signaling message which is generated in the second network element and transmitted to the first network element, the possible allocation of the at least one payload data connection to a multiplexed connection is indicated to the first network element. Using the method, it is advantageously not necessary for the first network element, which initiates the allocation, to know the destination nodes of the payload data connection. It is therefore possible for the standardized IPBCP protocol, in which the IPBCP Request Message that is transmitted by a first network element is generally sent without knowledge of the second network element which will receive this message, or the likewise standardized SIP signaling protocol to be expanded such that it includes the method. As a result of establishing the relevant payload data connection via a multiplexed connection, it is possible to transmit in particular compressed voice data using a significantly reduced bandwidth.
The method is also advantageous in that it is not necessary to introduce new messages in the IPBCP protocol, but merely to expand the existing messages in a suitable manner.
It is further advantageous that the method optionally allows the transport of a payload data connection between a first network element which supports the transport of data via a multiplexed connection, and a second network element which only supports the transport of payload data connections outside of multiplexed connections in accordance with existing standards.
When selecting the multiplexed connection, the second network element preferably considers whether sufficient free resources for the new payload data connection are present in the multiplexed connection, e.g. free address information for the payload data connection.
If the IPBCP protocol is used, a so-called IPBCP Request Message and an IPBCP Response Message are exchanged separately when establishing each payload data connection. In the IPBCP Request Message, the first network element specifies its IP address and a UDP port number in accordance with the existing standard. In order to indicate that the transport of a payload data connection over a multiplexed connection is desired, a newly developed SDP attribute is introduced. Alternatively, a new “MIME” parameter is used for the MIME Type of the IuFP protocol as defined in TS 29.414.
If the second network element does not support the transport of payload data connections via multiplexed connections, the second network element ignores the new unrecognized SDP attribute or the new MIME parameter, in accordance with the existing SDP standard, and sets up an individually transported payload data connection to the specified IP address and port number in accordance with the existing IPBCP standard. The necessary backwards-compatibility is therefore established.
If the second network element supports the transport of payload data connections via multiplexed connections, but decides not to utilize multiplexing for the specified payload data connection, the second network element sends an IPBCP Response Message in accordance with the existing standard in the same way and without expansions that are specified in the embodiments.
When a second network element which supports multiplexing receives the IPBCP Request Message specifying that multiplexing is desired, it selects a multiplexed connection to the IP address specified in the IPBCP Request Message. Alternatively, the multiplexed connection can also go to a port other than the port specified in the IPBCP Request Message.
In the IPBCP Response Message, the second network element notifies the first network element that multiplexing has been selected and specifies the selected multiplexed connection, preferably by the UDP port number, which the second network element uses for receiving the multiplexed connection. A new SDP attribute can be used for the purpose of specifying that multiplexing is selected, e.g. the same new SDP attribute that is used in the IPBCP Request Message for specifying that multiplexing is desired. Alternatively, a new “MIME” parameter for the MIME Type of the IuFP as defined in TS 29.414 is used for specifying that multiplexing is selected, e.g. the same new parameter that is used in the IPBCP Request Message. The specification of the port number which is used for receiving the multiplexed connection in MGW-B can be done within the so-called SDP “Media” line which describes the payload data connection, or using a new SDP attribute or MIME Type parameter.
Furthermore, the method advantageously allows the assignment of a unique identification code to the payload data connection within the multiplexed connection. This identification code can be specified e.g. within the data packets of the multiplexed connection, being allocated in each case to a transported data packet of the payload data connection, in order thus to indicate the payload data connection to which the transported data packet belongs.
After a multiplexed connection has been selected, the second network element preferably assigns a further identification code, which is unique within the multiplexed connection, to the payload data connection which has been newly allocated to this multiplexed connection, and notifies the first network element of the selected further identification code for each newly allocated payload data connection, using the message in which the second network element indicates whether and to which multiplexed connection each payload data connection is allocated.
This identification code can then be specified e.g. within the data packets of the multiplexed connection, being allocated in each case to a transported data packet of the payload data connection, in order thus to indicate the payload data connection to which the transported data packet belongs. For a payload data connection in this context, the same identification code is preferably used for data packets which are sent from the first network element to the second network element as for data packets which are sent from the second network element to the first network element.
For SDP, which is used in the case of IPBCP, the specification of the identification code preferably takes place by a new SDP attribute or MIME Type parameter, e.g. by the attribute or parameter which indicates that multiplexing is used.
As soon as a payload data connection is terminated, the identification code which was previously used for this payload data connection is preferably assigned to another payload data connection that has been newly allocated to the multiplexed connection. In order to prevent the same identification code from being inadvertently assigned to different new payload data connections within the same multiplexed connection simultaneously by the first and second network element, it is advantageous if the first and second network element are allotted different value ranges for determining the identification code. For example, the network element which first assigns a payload data connection to a new multiplexed connection can thereby be allotted the lower value range, while the other network element, which receives a message from the network element relating to the allocation of the payload data connection, is allotted the upper value range by this message.
In addition, the method advantageously supports the setting up of new multiplexed connections, in particular if no suitable multiplexed connection is yet available for the payload data connection. Such an automatic and dynamic setting up of multiplexed connections simplifies the operation of a communication system considerably.
When the message containing an address and indicating that the allocation of payload data connection(s) to one or more multiplexed connection(s) is desired is received from the first network element, in the event that no suitable multiplexed connections to the specified address are yet available or that no more resources are available on the existing payload data connections, it is correspondingly advantageous for the second network element to establish a new multiplexed connection to the specified address and assign this new multiplexed connection to the payload data connections.
Establishing the new multiplexed connection is preferably done by the second network element designating a multiplexed connection which was not previously available, e.g. by a previously unused UDP port number of the second network element, in the message to the first network element. When the message from the second network element is received, as a result of new address information being used, the first network element recognizes that a new multiplexed connection is being used. The first network element preferably first specifies a free UDP port number in the message to the second network element, and the second network element uses this UDP port number in order to send data to the first network element in a newly established multiplexed connection. If the second network element selects an already existing multiplexed connection, however, the second network element uses a different port number of the first network element, which port number was already allocated to this multiplexed connection previously. A multiplexed connection is preferably closed as soon as the last payload data connection which is transported therein is terminated.
The embodiments are also suitable for other networks which provide the so-called “Session Initiation Protocol” (IETF RFC 3261) for the purpose of signaling and in which a large amount of payload data connections are exchanged between the same network elements, e.g. the so-called “Internet Multimedia Subsystem” (IMS), in the manner that has been standardized by ETSI TISPAN. For the purpose of describing the payload data connections, use is also made here of the SDP protocol which is exchanged in accordance with the so-called “SDP-Offer-Answer” mechanism (IETF RFC 3264) by a so-called SDP Offer Message and a subsequent SDP Answer Message, these being comparable with the IPBCP Request Message and the IPBCP Response Message.
Further advantageous embodiments of the method are derived from the further patent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects and advantages will become more apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1 shows the network components of a mobile communication network which interact for the purpose of executing the method by way of example in a schematic block diagram,
FIG. 2 shows the structure of a data packet of a multiplexed connection by way of example in a schematic illustration,
FIG. 3 shows an alternative structure of a data packet of a multiplexed connection by way of example in a schematic illustration, and
FIG. 4 shows the network architecture of an IMS-based communication system by way of example in a schematic block diagram.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made in detail to the preferred embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.
By way of example in a schematic block diagram, FIG. 1 illustrates a first network element, in particular a network node MSC-A, and a second network element, in particular a network node MSC-B, of a mobile communication system MKS, wherein the first and second network nodes MSC-A, MSC-A are designed as mobile switching centers in a preferred embodiment.
The first network node MSC-A features a first MSC Server unit MSC-S-A and a first Media Gateway unit MGW-A by way of example in the exemplary embodiment illustrated in FIG. 1 . In a similar manner, the second network node MSC-B features a second MSC Server unit MSC-S-B and a second Media Gateway unit MGW-B. The server and media gateway functionalities which are realized by separate units, and specifically by the first and second MSC Server unit MSC-S-A and the first and second Media Gateway unit MGW-A, MGW-B, can alternatively also be realized in a shared unit in each case.
In the present exemplary embodiment, the first and second network nodes MSC-A, MSC-B or their first and second Media Gateway units MGW-A, MGW-B are connected together via the one “Nb” interface, which uses the IP, UDP, RTP and IuFP protocol for transmitting data packets DP of a payload data connection that is to be established.
According to the embodiments, at least one multiplexed connection mv for transmitting at least one payload data connection is provided at the “Nb” interface. There also exists a BICC signaling connection between the first and second MCS Server Unit MSC-S-A, MSC-S-B, wherein the first and second MCS Server Unit MSC-S-A, MSC-S-B is connected via a signaling connection which is based on the ITU-T H.248 protocol to the first or second Media Gateway unit MGW-A, MGW-B respectively and controls it via this interface. The “BICC IP Bearer Control Protocol” (IPBCP) is supported by both the BICC signaling connection and the H.248 signaling connection.
The first network node MSC-A, or more precisely the first MSC Server unit MSC-S-A and the first Media Gateway unit MGW-A, is also connected to a “Radio Network Controller” (RNC) unit by the so-called “Iu” interface or an “Iu” data connection. The IP, UDP, RTP and IuFP protocol is also used by the Iu data connection for transmitting the data packets of a payload data connection.
FIG. 2 provides an exemplary illustration of the structure of a data packet DP of a multiplexed connection mv as per the embodiments, the connection being transmitted e.g. via the Nb data connection or Nb interface. The data packet DP is provided for the multiplexed data transmission of e.g. first to third payload data connections UC 1 , UC 2 , UC 3 .
To this end, the data packet DP features just one IP, UDP and RTP data field IP, UDP, RTP in each case, whereas the payload data of the first to third payload data connections UC 1 , UC 2 , UC 3 is transmitted in a discretely arranged data field IuFP 1 to IuFP 3 in each case, which preferably contains data of the IuFP and the payload data of the first, second or third payload data connection UC 1 , UC 2 , UC 3 in each case. The payload data can in each case be voice information which is encoded e.g. according to the AMR method.
For each payload data connection UC 1 to UC 3 , a multiplexed data field MP 1 , MP 2 , MP 3 is preferably also inserted in each case, the multiplexed data field containing at least a first to third identification code ID 1 , ID 2 , ID 3 which designates the respective payload data connection UC 1 , UC 2 or UC 3 within the multiplexed connection, and possibly further information relating to the length of the payload data that is being transmitted in each case and/or a time stamp. Provision can also be made for a first to third IuFP data field IuFP 1 , IuFP 2 , IuFP 3 .
An IPBCP Request Message and IPBCP Response Message are described in greater detail below by way of example, the messages being encoded by the “Session Description Protocol” (SDP) and being exchanged e.g. between the first and second network nodes MSC-A, MSC-B illustrated in FIG. 1 , in particular between the first and second Media Gateway units MGW-A, MGW-B.
IPBCP Request Message (MGW-A->MGW-B): Rq 1 c=IN IP4 host.anywhere.com Rq 2 m=audio 49170 RTP/AVP 97 Rq 3 a=rtpmap:97 VND.3GPP.IUFP/16000 Rq 4 a=fmtp:97 multiplex IPBCP Response Message (MGW-B->MGW-A): Rp 1 c=IN IP4 host.example.com Rp 2 m=audio 49320 RTP/AVP 97 Rp 3 a=rtpmap:97 VND.3GPP.IUFP/16000 Rp 4 a=fmtp:97 multiplex; user_connection_id=11
The IPBCP Request Message is generated in the first Media Gateway unit MGW-A of the first network node MSC-A and transmitted to the second Media Gateway unit MGW-B of the second network node MGW-B. By the multiplexing identification code “multiplex” for the MIME Type of the IuFP protocol, this being specified in the fourth line Rq 4 of the IPBCP Request Message, the first Media Gateway unit MGW-B notifies the second Media Gateway unit MGW-B that it wants the payload data connection which is specified in the IPBCP Request Message to be allocated to a multiplexed connection mv.
In the first line Rq 1 of the IPBCP Request Message, the first Media Gateway unit MGW-A specifies address information which is allocated to it, e.g. its IP address such as “host.anywhere.com”, to which the multiplexed connection is to be routed.
In the second line Rq 2 of the IPBCP Request Message, the first Media Gateway unit MGW-A specifies a free port number in the first Media Gateway unit MGW-A, e.g. “49170”, which port number can be used for establishing a multiplexed connection mv that does not yet exist at the time of the request, but can also be used for establishing a payload data connection outside of a multiplexed connection in accordance with the existing standard.
If no multiplexing identification code “multiplex” is provided in the fourth line Rq 4 of the IPBCP Request Message, the specified IP address and port number are intended for establishing a simple (i.e. non-multiplexed) payload data connection in a standard-compliant manner. In the first Media Gateway unit MGW-A, it is already anticipated that the second Media Gateway unit MGW-B might not support or comply with the allocation preference that is indicated by the multiplexing identification code “multiplex”, and might use the transmitted IP address and port number for establishing a simple non-multiplexed payload data connection to the first Media Gateway unit MGW-A.
Following receipt of the IPBCP Request Message, the second Media Gateway unit MGW-B allocates the port number of the desired multiplexed connection in the second Media Gateway unit MGW-B, e.g. the multiplexed connection having the port number “49320”, to a multiplexed connection mv to the received IP address “host.anywhere.com”.
In a preferred embodiment, the first and second Media Gateway unit MGW-B allocate an identification code within the allocated multiplexed connection mv (the identification code “11” in the present exemplary embodiment) to the payload data connection that must be established. In order to prevent the same identification code from being inadvertently assigned to different new payload data connections within the same multiplexed connection simultaneously by the first and second Media Gateway unit MGW-A, MGW-B, the first and second Media Gateway unit MGW-A, MGW-B are preferably allotted different value ranges for assigning the identification code. For example, the Media Gateway unit MGW-B which first assigns a payload data connection to a new multiplexed connection can thereby be allotted the lower value range, while the other Media Gateway unit MGW-A is allotted the upper value range.
If the second Media Gateway unit MGW-B finds that no multiplexed connection mv yet exists to the desired IP address “host.anywhere.com”, it establishes a new multiplexed connection mv to the IP address “host.anywhere.com” and the specified port number “49170” in the first Media Gateway unit MGW-A by an IPBCP Response Message. In this case, the allocated port number “49320” is a previously unused port number in the second Media Gateway unit MGW-B.
If an existing multiplexed connection is selected, however, the allocated port number “49320” of the second Media Gateway unit MGW-B corresponds to the port number of the existing multiplexed connection mv, which has been assigned the port number “49170” in the first Media Gateway unit MGW-A.
The information for establishing the payload data connection, which information is determined by the second Media Gateway unit MGW-B, is notified to the first Media Gateway unit MGW-A by the IPBCP Response Message.
By the multiplexing identification code “multiplex” for the MIME Type of the IuFP protocol, for example, the identification code being specified in the fourth line Rp 4 of the IPBCP Response Message, the first Media Gateway unit MGW-A is notified that the payload data connection described in the IPBCP Response Message has been allocated to a multiplexed connection. Using the additionally transferred parameter “user_connection_id” with the value “11”, the first Media Gateway unit MGW-A is informed of the identification code that has been allocated to the payload data connection within the multiplexed connection mv by the second Media Gateway unit MGW-B.
The first line Rp 1 of the IPBCP Response Message specifies the IP address, e.g. “host.example.com”, which has been allocated by the second Media Gateway unit MGW-B and to which the multiplexed connection mv leads.
The second line Rp 2 of the IPBCP Response Message specifies the port number “49170” which has been allocated by the second Media Gateway unit MGW-B and to which the multiplexed connection mv is routed in the second Media Gateway unit MGW-B. This therefore also indirectly designates the selected multiplexed connection mv. The second Media Gateway unit MGW-B can also induce the first Media Gateway unit MGW-A to establish a new multiplexed connection mv by specifying a previously unused port number.
A missing multiplexing identification code “multiplex” in the fourth line Rp 4 of the IPBCP Response Message informs the first Media Gateway unit MGW-A that a multiplexed connection mv is not used for establishing the payload data connection, but that this is being established in accordance with the currently standardized method as a simple non-multiplexed payload data connection by the transmitted IP address and the associated port number. An IPBCP Response Message without multiplexing identification code “multiplex” would also be sent by a previously standardized Media Gateway unit MGW- 2 which does not understand and therefore ignores the multiplexing identification code “multiplex” in the fourth line Rq 4 of the IPBCP Request Message and only supports the transport of payload data connections outside of multiplexed connections.
For the purpose of explaining an alternative use case for the method, FIG. 4 provides a simplified illustration in a schematic block diagram of the network architecture of a communication system that is based on an “Internet Multimedia Subsystem” (IMS) or IMS communication system IMS which features expansions that have already been standardized by the standardization body “Telecoms & Internet converged Services & Protocols for Advanced Networks” (TISPAN) and protocols that are already in use.
The IMS communication system IMS features e.g. first to third communication terminals T 1 to T 3 which support the “Session Initiation Protocol” (SIP) SIP in each case. The first to third communication terminals T 1 to T 3 are connected via the SIP protocol SIP (SDP) to a so-called “Access Boarder Gateway” (ABG) unit ABG and thereby linked to the SIP core network.
According to the standard which is defined by TISPAN, the functions that are normally allocated to the ABG unit ABG are realized by a plurality of interconnected network elements, and specifically by a so-called “Proxy Call Session Control Function” (P-CSCF) unit P-CSCF, a “Service-based Policy Decision Function” (SPDF) unit SPDF and a “Boarder Gateway Function” (BGF) unit BGF. In this type of configuration, on the basis of the SIP signaling data, the P-CSCF unit P-CSCF controls the SPDF unit SPDF which in turn controls the BGF unit BGF.
In the IMS communication system IMS, provision can also be made for so-called “Application Server” (AS) units which offer selected applications such as a “Push-to-Talk” communication service, for example.
Provision can also be made for “Media Resource Functions” (MRF) units MRF, which serve as conference bridges and are made of two network elements, specifically a so-called MRF Controller (MRFC) unit MRFC and a so-called MRF Processor (MRFP) unit MRFP.
Furthermore, the IMS communication system IMS can be connected to other IP or IMS communication systems by a “Boarder Gateway” (BG) unit BG. For this purpose, the BG unit BG features an “Interconnection Boarder Control Function” (IBCF) unit IBCF, an SPDF unit SPDF and a BGF unit BGF.
The IMS communication system IMS can be connected to a “Public Switched Telephone Network” PSTN by a “PSTN Gateway” (PSTN-G) unit PSTN-G. For this purpose, the unit features a “Media Gateway Control Function” (MGCF) unit MGCF and an “Internet Multimedia Media Gateway” (IM-MGW) unit IM-MGW.
The SIP signaling is routed by a “Call Session Control Functions” (CSCF) unit CSCF in the IMS communication system IMS, wherein the first to third communication terminals T 1 to T 3 exchange signaling data via the P-CSCF unit P-CSCF, which in turn exchanges SIP signaling data via the CSCF unit CSCF, with the IBCF, MGCF, MRFC and AS unit IBCF, MGCF, MRFC, AS in each case, the signaling data being transmitted using the SDP protocol.
For the purpose of transporting payload data between the first to third communication terminals T 1 to T 3 , the BGF unit BGF, the IM-MGW unit IM-MGW, the MRFP unit MRFP and the AS unit AS, these are interconnected by the RTP, UDP and IP protocols RTP, UDP, IP. In addition to the payload data, the “Real Time Control Protocol” (RTPC) which is standardized in RFC 3550 is also transmitted. Unlike the exemplary embodiment of the 3GPP CS domains as illustrated in FIG. 1 , the IuFP protocol is not used in the IMS communication system IMS. However, it is also anticipated here that a multiplicity of payload data connections will be transmitted almost simultaneously between two network elements of the IMS core network (BGF, IM-MGW, MRFP or AS in each case), and therefore a wide bandwidth will be required. In order that bandwidth can be economized, it is appropriate to provide multiplexed connections for transmitting a plurality of payload data connections having similar attributes.
The structure of a data packet DP of a multiplexed connection mv is illustrated in FIG. 3 by way of example, and shows the possible format of a multiplexed data packet such as could be provided e.g. at the interfaces indicated in FIG. 4 . The structure corresponds largely to the structure illustrated in FIG. 2 . By contrast, however, the RTP data fields RTP 1 and RTP 2 which support the RTP protocol are provided instead of the IuFP data fields IuFP 1 to IuFP 3 . This is required in particular due to the payload data connection which is realized as an end-to-end connection, in order to allow for a reconstruction of the payload data immediately in the encoding unit or decoding unit, e.g. in the relevant communication terminal T 1 to T 3 .
In addition to the payload data connections which are transmitted in accordance with the RTP protocol, provision can also be made for allocated RTCP control connections in a data field of the multiplexed data packet DP. In a similar manner to the other payload data connection, an identification code ID 3 is assigned to it for this purpose.
Furthermore, an RTP data field RTP is likewise provided in the header of the multiplexed data packet DP. Information relating to jitter and packet losses on the transmission link, which might be present between the individual network elements in the core network (BGF, IM-MGW, MRFP or AS in each case), can be obtained from the data that is transmitted in the RTP data field RTP.
The structure of an “SDP Offer Message” and an “SDP Answer Message” in accordance with the IETF RFC 3264 standard is explained below by way of example, the messages being exchanged e.g. via the SIP signaling protocol SIP between e.g. two network elements or node elements of the IMS core network IMS and containing the expansions.
The AS unit AS, the BGF unit BGF, the ABG unit ABG, the PSTN-G unit PSTN-G or an MRF unit MRF, for example, can be provided as node elements. The structure of a multiplexed data packet DP as illustrated in FIG. 3 is used by way of example.
Unlike the previously described structure of the IPBCP messages, the message exchange that is illustrated below additionally serves to allocate the encoding methods that are used for the transmission, and can relate to a plurality of payload data connections.
SDP Offer Message (Node A->Node B): O 1 c=IN IP4 host.anywhere.com O 2 m=audio 49170 RTP/AVP 98 3 96 97 O 3 a=rtpmap:98 VND.3GPP.IUFP/16000 O 4 a=fmtp:98 multiplex O 5 a=rtpmap:97 AMR O 6 a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 O 7 a=rtpmap:96 telephone-event SDP Answer Message (Node B->Node A): A 1 c=IN IP4 host.example.com A 2 m=audio 49320 RTP/AVP 98 A 3 a=rtpmap:98 VND.3GPP.IUFP/16000 A 4 a=fmtp:98 multiplex; rtp_payload_types=96,97; user_connection_id=11; rtcp_connection_id=12; A 5 a=rtpmap:97 AMR A 6 a=fmtp:97 mode-set=0,2,5,7; mode-change-period=2 A 7 a=rtpmap:96 telephone-event
In this context, the “SDP Offer Message” is transmitted from the first network node Node A to the second network node Node B. Different encoding methods, specifically “GSM-FR”, “AMR” and “Telephone event”, are specified in the second line O 2 of the SDP Offer Message, for example. These encoding methods are entered using the RTP parameter “payload types” by allocating the values “3”, “96” and “97” in the second line O 2 of the SDP Offer Message. These are described further by additional parameters which are provided in the fifth, sixth and seventh lines O 5 , O 6 and O 7 in accordance with the standardized SDP protocol. The value “98”, which specifies the multiplexed IuFP protocol and is described in greater detail by the further parameters provided in the third and fourth line O 3 , O 4 , is additionally assigned in the second line O 2 as the RTP Payload Type.
Using the parameter “multiplex” for the MIME Type of the IuFP protocol, the parameter being specified in the fourth line O 4 , the first network node Node A which generates the SDP Offer Message tells the second network node Node B that it wants the payload data connection(s) that are described in the second line O 2 to be allocated to a multiplexed connection.
In the first line O 1 of the SDP Offer Message, the first network node Node A indicates the IP address it has been allocated, e.g. “host.anywhere.com”, to which the multiplexed connection mv is to be routed.
In the second line O 2 of the SDP Offer Message, the first network node Node A specifies a free port number it has been allocated, e.g. “49170”, which can be used for establishing a new multiplexed connection. If no “multiplex” parameter is contained in the SDP Offer Message, the specified IP address and port number are intended to be used—in a similar manner to the method described above—for establishing a simple non-multiplexed payload data connection. If there is no provision for the IuFP protocol to support a multiplexed transmission and/or the RTP Payload Type in the second network node Node B, the IP address and port number can likewise be used for establishing a simple non-multiplexed payload data connection to the first network node Node A.
Following analysis of the SDP Offer Message, the second network node Node B selects a multiplexed connection to the IP address “host.anywhere.com”, e.g. the multiplexed connection having the port number “49320” in the second network node Node B.
The second network node Node B also selects from the encoding methods which are indicated by the SDP Offer Message, e.g. “AMR” and “Telephone event” (RTP Payload Types 96 and 97). In addition, the second network node Node B assigns a first identification code, e.g. “11”, to the payload data connection and a further identification code to the allocated RTCP connection, e.g. “12”, for the purpose of identifying the payload data connections.
In the event that a multiplexed connection to the specified IP address “host.anywhere.com” does not yet exist, this is established by the SDP Answer Message to the second network node Node B, and specifically to the IP address “host.anywhere.com” and to the port number “49170” in the first network node Node A. In this case, the port having the number “49320” is a port which was previously unused by the second network node Node B. If an existing multiplexed connection mv is selected, the port number “49320” specifies the port number which has been allocated to the multiplexed connection mv in the second network node Node B, and the port number “49170” specifies the port number which has already been allocated to this multiplexed connection in the first network node Node A.
The second network node Node B generates an SDP Answer Message and transmits this to the first network node Node A, wherein the message contains the following information.
The selected RTP Payload Type for the IuFP protocol, specifically e.g. “98”, is specified in the second line A 2 of the SDP Answer Message, and the parameter “multiplex” for the MIME
Type of the IuFP protocol is specified in the fourth line A 4 , thereby notifying the first network node Node A that the payload data connection described in the SDP media line A 2 is allocated to a multiplexed connection mv.
By the parameter “rtp_payload_types” which is specified in the fourth line A 4 for the MIME Type of the IuFP protocol, the second network node Node B notifies the first network node Node A of the RTP Payload Types selected for this payload data connection, e.g. “96” for the AMR encoding method and 97 for the “Telephone event” encoding method. The cited RTP Payload Types are defined in greater detail in the fifth to seventh lines O 5 to O 7 .
The parameter “user_connection_id” is inserted in the fourth line A 4 for the MIME Type of the IuFP protocol, and notifies the first network node Node A that the payload data connection described in the second line A 2 has been assigned the first identification code, e.g. “11”. By the parameter “rtcp_connection_id” which is specified in the fourth line A 4 for the MIME Type of the IuFP protocol, the first network node Node A is notified that the RTCP connection which is allocated to the payload data connection described in the second line A 2 is assigned the second identification code, e.g. “12”.
The IP address e.g. “host.example.com” which is allocated to the second network node Node B and via which the multiplexed connection mv travels is allocated in the first line A 1 , and the port number e.g. “49170” at which the data packets DP that are transmitted via the multiplexed connection are received is specified in the second line A 2 .
The second network node Node B can instruct the first network node Node A to establish a new multiplexed connection by using a previously unoccupied port number. If the “multiplex” parameter is not contained in the SDP Answer Message, the transmitted IP address and port number can be used for establishing a simple non-multiplexed payload data connection.
As shown in FIG. 4 , the first and second network nodes Node A, Node B can in each case comprise a control unit which is responsible for the SIP signaling, e.g. the P-CSCF, IBCF, MGCF or MRFC unit P-CSCF, IBCF, MGCF, MRFC, and a processor unit which is responsible for the payload data connections, e.g. the BGF, IM-MGW or MRFP unit BGF, IM-MGW, MRFR. Processor unit and control unit communicate with each other in accordance with e.g. the ITU-T H.248 standard in each case. In a preferred embodiment, the processor unit is responsible for the management of the multiplexed connections mv and for the assignment of the address information relating to the payload data connections.
Before the transmission of the SDP Offer Message, the control unit and the processor unit of the respective network node Node A, Node B exchange messages in accordance with the existing standard. In particular, the processor unit notifies the control unit of its IP address “host.anywhere.com” and the port number it has been assigned, e.g. “49170”. The signaling is additionally expanded to the effect that the processor unit notifies the control unit that it desires the use of a multiplexed connection. For this purpose, for example, the RTP payload in the IuFP protocol as per the second to fourth lines O 2 to O 4 can be transmitted from the processor unit to the control unit using a selected H.248 message.
Between receiving the SDP Offer Message and sending the SDP Answer Message, messages are exchanged between the control unit and the processor unit of the relevant network node Node A, Node B in accordance with the existing standard. As part of this activity, the processor unit already indicates e.g. the IP address and the port number which are received in the SDP Offer Message. In a preferred embodiment, the control unit also signals to the processor unit that multiplexing is desired. This is done e.g. by forwarding the RTP Payload for the IuFP protocol in accordance with the second to fourth lines O 2 to O 4 by a suitable H.248 message.
The processor unit then selects the multiplexed connection and assigns the relevant identification codes to the payload data connections. The processor unit already notifies the control unit of its IP address and the port number it has been assigned.
If an SPDF is located between control unit and processor unit, this forwards the described information in each case.
The subject matter has been described in the foregoing with reference to an exemplary embodiment. It is obvious that numerous changes and modifications are possible without thereby departing from the fundamental inventive idea of the invention.
The system also includes permanent or removable storage, such as magnetic and optical discs, RAM, ROM, etc. on which the process and data structures of the present invention can be stored and distributed. The processes can also be distributed via, for example, downloading over a network such as the Internet. The system can output the results to a display device, printer, readily accessible memory or another computer on a network.
A description has been provided with particular reference to preferred embodiments thereof and examples, but it will be understood that variations and modifications can be effected within the spirit and scope of the claims which may include the phrase “at least one of A, B and C” as an alternative expression that means one or more of A, B and C may be used, contrary to the holding in Superguide v. DIRECTV, 358 F3d 870, 69 USPQ2d 1865 (Fed. Cir. 2004). | The invention relates to a method for allocating at least one user data link to a multiplex connection provided between a first network element and a second network element. According to the method, the first network element generates a first signaling message and transmits the same to the second network element, the first signaling message indicating to the second network element that the first network element is available to transfer the at least one respective user data link via one respective multiplex connection. The second network element assigns one multiplex connection between the first network element and the second network element to each of the at least one user data link or selects a transfer outside a multiplex connection for the user data link in accordance with the indicated availability of the first network element and depending on whether the second network element supports the transfer of the at least one user data link via multiplex connection. The possibility of allocating the at least one user a data link to a multiplex connection is indicated to the first network element by a second signaling message that is generated in the second network element and is transmitted to the first network element. | 7 |
CLAIM OF PRIORITY
This application is a continuation-in-part of U.S. patent application Ser. No. 12/761,410 filed on Apr. 16, 2010 titled “A LIQUID SHEETING DEVICE”.
FIELD OF TECHNOLOGY
This disclosure relates generally to a technical field of mechanical devices and, in one embodiment, to a method, system and apparatus of a liquid sheeting device.
BACKGROUND
A liquid dispensing apparatus for decorative or industrial purposes may be designed for dispensing liquid in a uniform sheet. Such a liquid dispensing apparatus may be used for a variety of applications because the apparatus can be sized to produce many sizes of liquid sheeting. In addition, the liquid dispensing apparatus may be inexpensive as it may be constructed from common elements and in few manufacturing steps.
SUMMARY
A method, system and apparatus of a liquid sheeting device is disclosed. In one embodiment, an apparatus includes a channel to allow a flow of liquid (e.g., water), wherein the channel is coupled to a liquid source. The channel may have one or more ends, and one or more of the ends of the channel may be coupled to a liquid source. The apparatus may include a liquid sheeting component extending along the longitudinal axis of the channel, from inside the channel down through the bottom of the channel. The liquid sheeting component may comprise one or more sheeting elements structurally coupled to the channel. The liquid sheeting component may divide the channel into two or more side-by-side sub-channels along a longitudinal axis of the channel. The liquid sheeting component may divide the channel into a right and left channels. The liquid sheeting component may divide a bottom portion of the channel but may leave a top portion of the channel undivided. The liquid sheeting component may further comprise an outlet extending along the longitudinal axis of the channel to allow the liquid in the channel to fall through the outlet in a sheet. The apparatus may further include one or more caps coupled to one or more ends of the channel. One or more caps may include a liquid inlet. The channel may be, but is not limited to, any of a pipe, a conduit, and a duct.
In another embodiment, a system may include a liquid sheeting apparatus that may include a channel and a liquid sheeting component coupled to the channel to generate a sheet of liquid. In addition, the system may also include a liquid source. The system may also include a pumping device to supply a continuous flow of liquid to the liquid sheeting apparatus through a connection. The connection may be a pipe or tube.
In yet another embodiment, a method of manufacturing an apparatus may include forming a longitudinal opening along the bottom of a channel. The method may include forming a liquid sheeting component of length and width substantially equal to the opening of the channel, with an outlet gap running through the center of the liquid sheeting component. The liquid sheeting component may be made of one or more sheeting elements or may be one formed piece. In some embodiments the sheeting elements are sheets of plastic. The sheeting elements may be a plastic, metal or any suitable material. The method may also include coupling and securing the liquid sheeting component to the channel such that a part of the liquid sheeting component is inserted through the opening of the channel such that a part of the liquid sheeting component is above the inside surface of the channel and a remaining part of the liquid sheeting component is below the channel.
The method and apparatus may further include coupling an inlet cap to a first end of the channel and coupling a covering cap to the second end of the channel. In some embodiments, the inlet cap may comprise an inlet offset to one side of the center of the inlet cap to enable a flow of liquid into the channel.
The method may include selecting one or more pieces of sheeting material to form the sheeting element(s) of the liquid sheeting component. In some embodiments, the liquid sheeting component may have one sheeting element situated adjacent to the outlet wherein the length of the sheeting element and the length of the outlet are along the longitudinal axis of the channel. In some embodiments, the liquid sheeting component may have two sheeting elements situated on either side of the outlet with two thin side-members keeping the two pieces of sheeting material from touching. In some embodiments, a distance between the two pieces is the outlet gap. In this and other embodiments, the inside of the liquid sheeting component may be a narrow rectangular tube with the two sheeting elements forming the longitudinal sides of the rectangular tube and the two thin side-members forming the short sides of the rectangular tube. In some embodiments, one sheeting element may have a greater width than the other sheeting element. In some embodiments, the wider sheeting element may extend vertically above the narrower sheeting element a distance greater than or equal to the width of the outlet gap. In some embodiments, the liquid sheeting component may be secured to a horizontal channel such that the tubular portion of the liquid sheeting component runs generally vertically allowing liquid in the channel to flow into the top of the liquid sheeting component and out the bottom of the liquid sheeting component.
The method may include manufacturing the inlet cap such the inlet is horizontally offset from a virtual centerline of the channel. In some embodiments, the offset may be such that the entire inlet is confined to one side of a virtual centerline of the channel. In some embodiments, the inlet may be offset towards the side of the liquid sheeting component having the longer sheeting element. The method and system may also include providing a route for liquid flow from a liquid source to the channel using a tube inserted through the inlet cap. The channel described herein may be any of, but not limited to a pipe, a conduit, and a duct.
Other embodiments will be apparent from the following description and the appended claims.
BRIEF DESCRIPTION OF THE VIEWS OF DRAWINGS
Example embodiments are illustrated by way of example and not limitation in the figures of accompanying drawings, in which like references indicate similar elements and in which:
FIG. 1 is a cross section view of a liquid sheeting apparatus, according to one or more embodiments.
FIG. 2 is a top view of an assembly tool that may be used to mount the liquid sheeting apparatus, according to one or more embodiments.
FIG. 3 is a cross sectional view of a liquid sheeting apparatus, according to an alternate embodiment.
FIG. 4 is an angled view of the liquid sheeting apparatus, according to one or more embodiments.
FIG. 5 is a cross sectional view of the liquid sheeting apparatus illustrating a constructed structure, according to an example embodiment.
FIG. 6 is a schematic view of an inlet cap illustrating a positional alignment of an oblong hole inlet with respect to a centre line of the inlet cap, and an insertion of a pipe into the positioned oblong hole, according to an example embodiment.
FIG. 7 is a back view of the liquid sheeting apparatus, according to one or more embodiments.
FIG. 8 is a front view of liquid sheeting apparatus, illustrating the assembly of the channel with end caps, according to an example embodiment.
FIG. 9 is a system view illustrating the liquid sheeting apparatus coupling with a liquid source, according to an example embodiment.
FIG. 10 is a cross section view of the liquid sheeting apparatus illustrating a flow of liquid in the liquid sheeting apparatus, according to an example embodiment.
FIG. 11 is a front view of the channel, according to an example embodiment.
FIG. 12 is an angled view of the individual separator pieces, according to an example embodiment.
FIG. 13 is a side view and front view of the assembled separator and a front view of the tapered end separator according to an example embodiment.
Other features of the present embodiments will be apparent from accompanying Drawings and from the Detailed Description that follows.
DETAILED DESCRIPTION
An apparatus, method, and system for liquid sheeting is disclosed. In the following description, for the purpose of explanation, numerous specific details of some embodiments are set forth in order to provide a thorough understanding of the various embodiments. Liquid sheeting is used for industrial, commercial, and decorative purposes in industrial, commercial, and residential areas. Liquid sheeting is provided by regulating a flow of liquid to obtain an effectively uniform sheet of liquid.
FIG. 1 is a cross section view of a liquid sheeting apparatus 150 , according to one or more embodiments. The liquid sheeting apparatus 150 is used to obtain a uniform sheet of liquid. The liquid sheeting apparatus 150 includes a channel, a liquid sheeting component (e.g., a separator 102 as described herein) and caps covering the ends of the channel. In one or more embodiments, the channel may be used for directing a flow of liquid. The channel may be a concrete cylindrical shaped pipe, a square shaped metal pipe, or another channel capable of containing liquid according to the requirements of applications. In an example embodiment, a Poly Vinyl Chloride (P.V.C) pipe 100 may be used as a channel to direct the flow of liquid. The separator 102 may be a component used to direct a flow of liquid from the channel to an outlet. The separator 102 may separate or divide the channel into right-and-left sub-channels or one or more side-by-side sub-channels along the longitudinal axis of the channel. The side-by-side sub-channels may have a vertical side or may have a non-vertical side. The separator 102 may separate or divide a bottom portion of the channel but may leave a top portion of the channel undivided. The separator 102 may comprise the outlet 104 of the liquid sheeting apparatus 150 . In one or more embodiments, the dimensions of the separator 102 and the size of the lip 109 of the separator 102 can modified to meet the requirements of the application. The pipe 100 may be cut along its length to create a slot or opening for the separator 102 . In one or more embodiments, the separator 102 may be comprised of one or more liquid sheeting elements 111 , 112 made up of any material including, but not limited to, metal and plastic. The pipe 100 length may be cut according to the dimensions of the separator 102 such that the separator 102 may fit in the pipe 100 . In alternate embodiments, a metal sheet 304 may be used to design the liquid sheeting apparatus. The metal sheet may be bent and designed as the liquid sheeting apparatus to generate a thin sheet of liquid. Caps for the liquid sheeting apparatus may be designed as required by the application. FIG. 3 illustrates a cross section view of the liquid sheeting apparatus constructed using a metal sheet, according to an alternate embodiment. In other embodiments, plastic may be used for designing the liquid sheeting apparatus as illustrated in FIG. 3 . In some embodiments the channel and separator may be manufactured as one piece rather than assembled from separate components. In some embodiments one or more caps may be manufactured as part of the channel rather than assembled from separate components.
In an example embodiment, a round P.V.C. pipe 100 with dimensions of 21 inches in length, an outer diameter of 2.375 inches, and an inner diameter of 2 inches is used as the channel. The P.V.C. pipe is used as a channel in the example embodiment because of light weight, low cost, portability, and ease of use. An 18 inch line may be drawn along the length of the pipe leaving 1.5 inches on both the ends of the pipe. A slot 1108 measuring 18 inch in length and 0.25 inch to 0.281 inch wide may be cut over the drawn line along the length of the pipe using a router and a 0.25 inch straight bit tool (as illustrated in FIG. 11 ).
The separator 102 (e.g., a liquid sheeting component), as illustrated in the example embodiment, may be of plastic material. A plastic sheet of thickness 0.083 to 0.09375 may be used and four pieces of the example dimensions may be cut namely, the first piece 1202 measuring 2.75 inch×18 inch, the second piece 1204 measuring 3 inch×18 inch, and the third piece 1206 and the fourth piece 1208 measuring 2.75 inch×0.125 inch may be cut (as illustrated in FIG. 12 ). These four cut pieces may be coupled together by adhesion or other means. The third piece 1206 measuring 2.75 inch×0.125 inch may be secured flush with three edges of the first piece along a 2.75 inch sides of the first piece 1202 using a quick bond glue or other suitable means. The forth pieces 1208 may be similarly secured flush with three edges of the first piece along the other 2.75 inch side of the first piece 1202 , and on the same surface of the first piece. The second piece 1204 measuring 3 inch×18 inch may then be coupled to the third piece 1206 and forth piece 1208 leaving a 0.25 inch×18 inch lip 1302 extending on one side and flush with the other pieces elsewhere. In some embodiments the size of the lip may be related to the time it may take for the apparatus to purge itself of air before producing a smooth sheet. In this example, the coupled separator component 1304 may have an outlet gap 1306 of 0.083 to 0.09375 inch between the first and second pieces, and a total thickness of 0.25 to 0.281 inch. (As illustrated in FIG. 13 ). The separator 1304 may be designed with other dimensions, in any preferred way based on a design required. FIG. 13 illustrates an example of a flat end separator and a tapered end separator 1350 .
FIG. 2 is a top view of an assembly tool of the liquid sheeting apparatus, according to some embodiments. In some embodiments, the assembly tool may be used to align the separator 102 component into the slot created in the pipe 100 . The assembly tool 201 may be of any material and dimensions, according to the requirements of the applications. In the example embodiment, an assembly tool measuring 17.5 inch×4 inch may be cut from 0.083 to 0.09375 plastic sheet. The assembly tool 201 may be inserted in the separator 102 assembly as shown in FIG. 2 . The assembly tool may be positioned and temporarily secured inside the separator such that 0.125 inch to 0.25 inch of the assembly tool extends beyond the lip of the separator 102 .
In the example, the separator 102 component along with the assembly tool may be placed in the slot that was created in the P.V.C. pipe 100 . In the example embodiment, the separator and assembly tool may be placed in the 0.25 to 0.281 inch gap of the 2 inch P.V.C. pipe 100 such that the assembly tool bottoms out on the inside of the P.V.C. pipe 100 ensuring the lip gap 502 between the inside of the P.V.C. pipe 100 and the separator 102 lip may be 0.125 inch to 0.25 inch. The lip gap may be the shortest distance between the top of the separator and the inside of the pipe. In the example embodiment, epoxy resin 400 may be applied on the coupling areas of the P.V.C. pipe 100 where the separator 102 and the P.V.C. pipe 100 are aligned. In some embodiments, the epoxy resin may be applied at coupling areas internal to the pipe 100 and external to the pipe (e.g., as illustrated in FIG. 4 ).
In the example, epoxy resin 400 may be used because of its high strength, dimensional stability corrosion resistance, and liquid proofing. In the example, the separator 102 may be coupled to the inside of the P.V.C. pipe 100 by applying the epoxy resin 400 into the P.V.C. pipe 100 . The epoxy resin 400 may be left to dry. When the epoxy resin 400 dries the example separator 102 may have a liquid-tight bond with the P.V.C. pipe 100 . The example assembly tool may be removed once the liquid-tight bond is achieved between the separator 102 and the P.V.C. pipe 100 (As illustrated in FIG. 4 and FIG. 5 ).
In some embodiments liquid may be provided through an inlet cap 602 (e.g., illustrated in FIG. 6 ). According to the example embodiment, the inlet cap 602 may be coupled to either end of the pipe 100 . In other embodiments the liquid may be provided through an inlet in the side of the pipe rather than, or in addition to, an end of the pipe.
FIG. 6 is a schematic view of an inlet cap of some embodiments, illustrating a positional alignment of an oblong hole 604 with respect to a centre line of the cap, and an insertion of a tube 612 into the positioned oblong hole, according to an example embodiment. In the example embodiment, the inlet cap 602 is a P.V.C. pipe cap designed for use with P.V.C. pipe with an outside diameter of 2.375 inches. In some embodiments, an oblong hole 604 may be created in one half of the cap, offset from a vertical center line 606 of the cap. The dimensions of the oblong hole 604 , according to the example embodiment, may be 1.5 inch long×1 inch wide. In alternate embodiments, any kind of opening may be formed, not limited to an oblong hole.
According to the example embodiment, a P.V.C. tube 612 measuring 4 inch in length having an outer diameter 1.25 inch and with an inner diameter of 1 inch is cut. In the example, the tube 612 may be deformed and inserted into the oblong hole 604 cut in the inlet cap 602 and positioned such that 1.5 inch of the tube may extend out from the closed end 610 of the inlet cap 602 . The cap and the P.V.C. tube may be coupled using epoxy resin to obtain a liquid tight seal. In some embodiments a piece of liquid proof foam 804 may be inserted into the inlet cap 602 and the end cap 704 such that the foam may compress against the separator inside the P.V.C. pipe when the end cap 704 and the inlet cap 602 (as illustrated in FIG. 8 ) are coupled to the P.V.C. pipe 100 . In some embodiments, the foam 804 provides a snug fit between the inside of the P.V.C. pipe 100 , the inlet tube 802 , the separator 102 , and the inlet cap 702 . In some embodiments the foam provides a liquid-tight fit between the pipe, tube, inlet cap, and separator when sealed. FIG. 7 is a back view of the liquid sheeting apparatus, according to one or more embodiments. In the example, the inlet cap may be installed such that the inlet tube is on the side of the separator 102 having the lip (as illustrated in FIG. 10 ). Introducing liquid into both ends of the liquid sheeting apparatus, and through the sides of the channel, may enable the apparatus to have extended lengths or mixing capabilities. In some embodiments, a blank 2 inch end cap may be installed on the end of the pipe not having an inlet. A rubber mallet may be used to tap the caps to obtain a snug liquid-tight fit.
FIG. 10 is a cross section view of an example liquid sheeting apparatus illustrating an example flow of liquid. In the example embodiment, liquid enters through the inlet cap of the apparatus (perpendicular to the FIG. 10 cross-section plane) into the inlet chamber 110 side of the separator 102 . In the example, the inlet flow 1002 circulates into chamber 106 and from there into the outlet gap 108 of the separator 102 which produces the outlet flow 1004 of the liquid in the form of a uniform sheet at the outlet 104 . In this example embodiment, the inlet chamber 110 and chamber 106 are sub-channels of the pipe 100 .
In alternate embodiments, the liquid sheeting apparatus can be constructed using metals or plastic and the material may be bent to obtain the apparatus elements. Parts may be welded or soldered according to the requirements of the applications. The liquid sheeting apparatus may be configured to be large or small. In some embodiments, the outlet gap 108 and the lip gap 502 of the separator 102 may be configured as per the application requirements. In some embodiments, a filter may be used to trap debris at the inlet cap or near a pump. In some embodiments, the plumbing and the inlet inner diameter may be half the inner diameter of the pipe 100 . Decorative elements or additional functional elements (e.g. mounting elements) may be added to the apparatus.
In the example embodiment, for a 2 inch inner diameter and 18 inch width liquid sheeting apparatus configuration, a 600 GPH submersible small pond pump with a 0.75 inch to 1 inch inner diameter may be used to produce the required pressure and volume to produce a 24 inch long liquid sheet that may be 17.75 inch wide at the top of the sheet tapering to about 16 inch wide at the bottom of the sheet. In some embodiments, the length of the liquid sheet may be adjusted by varying the pressure and volume of the liquid applied to the liquid sheeting apparatus 150 . In the example, plumbing may be used to connect the liquid sheeting apparatus 150 to the pump 902 . In the example, a connector 904 measuring 40 inch in length with 1 inch inner diameter may be used to connect the sheeting apparatus 900 with the pump 902 . (As illustrated in FIG. 9 ).
Although the present embodiments have been described with reference to specific example embodiments, it will be evident that various modifications and changes may be made to these embodiments without departing from the broader spirit and scope of the various embodiments. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. | A method, system and an apparatus for liquid sheeting is disclosed. In one embodiment, an apparatus includes a channel to contain a flow of liquid and a coupling to a liquid source. The channel may include one or more channel ends that may be coupled to the liquid source. The apparatus may also comprise a liquid sheeting component having a length extending along a longitudinal axis of the channel, the liquid sheeting component comprising an outlet extending through a bottom of the channel and a first sheeting element extending from inside the channel through the bottom of the channel, wherein the first sheeting element and the outlet are adjacent and extend the length of the liquid sheeting component and the liquid sheeting component divides the channel longitudinally into at least two side-by-side sub-channels such that a bottom portion of the channel is divided and a top portion of the channel is undivided. The apparatus may also comprise a second sheeting element extending from inside the channel through the bottom of the channel for the length of the liquid sheeting component. | 4 |
TECHNICAL FIELD
This invention relates to a device for distributing and/or feeding a hot flour-like material, in particular a stream of hot cement raw meal, in an installation for the production of cement clinker from cement raw meal, which is preheated in a heat-exchanger system and burned to cement clinker in a cylindrical rotary kiln.
BACKGROUND OF THE INVENTION
In installations for the production of cement clinker from raw meal, which is preheated and calcined before the burning operation, it is often necessary to divide a stream of hot cement raw meal into two meal discharges, that is, to convey hot raw meal into one and/or another meal discharge. Thus, for example, in the installation for the production of cement clinker from cement raw meal as shown in European patent document EP-B 0222 044 published Mar. 8, 1989, the preheated raw meal exiting downward from the next-to-last (second-lowest) cyclone stage must be divided in a controlled way into a calcination zone lying in the clinker-cooler off-gas line (tertiary air line), on the one hand, and a calcination zone lying in the rotary-kiln off-gas line, on the other. What is more, in certain dual-train installations (twin installations) where the cement raw meal of one train, precalcined in the rotary-kiln off-gas line, undergoes final calcination in the calcination zone of the other train, operated on hot clinker-cooler off-gas, after the installation has been started up, precalcined cement raw meal exiting from the lowest cyclone stage of the rotary-kiln off-gas train must be admitted by means of a changeover flap not to the rotary kiln but to the secondary calcination zone of the other train, which is ready for operation.
The distribution or changeover of the stream of hot raw meal has heretofore been effected with a distributor housing, to the top of which the hot meal delivery line can be connected and to the bottom of which two hot meal discharges can be connected, so that the distributor housing is also called a "breeches pipe" because of its shape. In the breeches pipe, a flap is pivotably arranged, by means of the pivot actuation of which flap the stream of hot cement raw meal, which can exhibit a temperature of, for example, 800 to 900° C., is distributed or changed over. The pivotable flap in particular is obviously subjected to severe thermochemical and abrasive wear.
Also subjected to severe wear are "impingement gates," which in cement plants are built transversely into a hot-gas line coming from the rotary kiln and/or from the clinker cooler and have the task of uniformly distributing or suspending, over the hot-gas cross section, preheated cement raw meal, which is introduced into the hot-gas line from the side.
What is more, in cyclone suspension-type preheater trains having cyclones arranged one above another through which hot gas flows in order to heat cement raw meal, "flap boxes" or "oscillating feeders" and also double oscillating feeders are built into the meal downpipes, in which boxes one or two weighted oscillating flaps are integrated, which have the task of holding back the stream of hot gas on the one hand, and on the other hand, by means of pivoting of the flaps, of allowing the stream of hot raw meal to pass downward through the meal downpipe after a certain solids burden. These oscillating flaps are also subjected to severe wear.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of the invention to create, especially for cement plant engineering, a device for distributing and/or feeding a hot stream of flour-like material, of which device the internal control elements are subjected to severe wear, in particular the actuator, have a long service life.
In this invention the device for distributing and/or transporting-feeding a stream of hot flour-like material, has a pivoting flap/oscillating flap or impingement gate, which is especially subject to wear, is made as a hollow plate-shaped body through which coolant flows, by way of at least one coolant inlet opening and at least one coolant discharge opening. For the sake of simplicity, outdoor air is used as cooling air, which is forced through the plate-shaped hollow body by a cooling-air fan or by a connection to the compressed-air system. The coolant cools the metallic hollow flap or hollow impingement gate, including the surface thereof. Solid buildups on the cooled, comparatively lightweight elements according to the invention are avoided. On the whole, the lifetime or service life of the hot-meal distributor device or hot-meal feeder is very long.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention and its further features and advantages are explained in more detail on the basis of exemplary embodiments illustrated schematically in the Drawing in which:
FIG. 1 shows, in side view, a breeches-pipe-shaped hot-meal distributor housing having an air-cooled adjustable flap for the distribution/changeover of a stream of hot meal arriving from above into one and/or another discharge, viewed in the direction of the arrow I of FIG. 2;
FIG. 2 shows another side view, offset 90° from FIG. 1, of the hot-meal changeover box of FIG. 1, having an integrated air-cooled changeover flap with parts omitted for illustration purposes;
FIG. 3 shows, in vertical section, an air-cooled impingement gate built into a rotary-kiln off-gas riser below the hot-meal inlet opening;
FIG. 4 shows a somewhat enlarged detail of the vertical section through the air-cooled impingement gate of FIG. 3;
FIG. 5 is a top view, partly in horizontal section, of the air-cooled impingement gate of FIG. 4; and
FIG. 6 shows in schematic detail a "dual-train" installation (twin installation) for the production of cement clinker from cement raw meal, which has an integrated air-cooled hot-meal changeover flap and an integrated air-cooled impingement gate.
DETAILED DESCRIPTION OF THE INVENTION
The dual-train installation for the production of cement clinker from cement raw meal, shown in FIG. 6, has a left train, through which off-gas from a rotary kiln 10 flows, and a right train, which is supplied with high-temperature cooler off-gas from hot cooler off-gas via a tertiary air line 11 of the clinker cooler, not shown. Each of the two trains has cyclone suspension-type preheater trains operated separately, of each of which, for the sake of simplicity, only the two lowest cyclone stages 12, 13 and 14, 15 are shown. Of the entire quantity of raw meal processed in the dual-train installation, approximately 50% of the raw meal, for example, can be admitted to the left train at 16, and similarly approximately 50% of the raw-meal quantity, for example, can be admitted to the right train at 17. The hot raw meal from the second-lowest cyclone stage 12 of the left train, at roughly 800° C., is introduced into the hot rotary-kiln off-gas line, at roughly 900 to 1100° C., via line 18, and there precalcined with or without the addition of fuel. The point of raw-meal inlet to the rotary-kiln off-gas line is located above an impingement gate 19, which has the purpose of uniformly distributing the inlet hot raw meal over the cross section of the rotary-kiln off-gas.
When the installation of FIG. 6 is started up, no hot cooler off-gas from the clinker cooler is available to operate the right train. At this stage, the hot meal 20, at roughly 800 to 900° C., separated from the rotary-kiln off-gas in the lowest cyclone stage 13 of the left train, is admitted directly to the inlet chamber of the rotary kiln 10 by apportioning box 21, whose oscillating flap 22 has taken up the right pivoted position, via the material discharge pipe 23. After startup operation has come to an end, when sufficiently hot cooler off-gas is available via the tertiary air line 11, the flap 22 of the changeover box 21 is changed over and the hot meal of the left train is inlet via hot-meal line 24 to the calciner 26 in the clinker cooler off-gas line 11 of the right train, which is fitted with secondary firing 25, into which calciner the raw meal from the second-lowest cyclone stage 14 of the right train is also inlet via line 27. Finally, all the cement raw meal calcined in the calciner 26 is separated from the hot off-gas stream 28 in the lowest cyclone 15 of the right train and inlet, as highly (for example, 95%) calcined cement raw meal 29, to the rotary kiln 10, in the sintering zone of which it is burned to cement clinker.
The hot-meal apportioning box or distributor box 21, having the cooled control flap 22, is detailed in FIGS. 1 and 2. The flap 22, pivotable about its bottom end, is made as a hollow body through which coolant flows, which hollow body is arranged in the breeches-pipe-shaped housing 21 and, depending on the pivoted position, discharges the inlet hot-meal stream 20 into one and/or the other material discharge 23, 24. As shown in FIG. 2, at least one web 30, arranged transversely to the flap plane, is built into the interior of the hollow flap 22, which web diverts the coolant, cooling air in the exemplary embodiment, admitted via one end of the hollow flap shaft 31, through the cavity in the flap to the other end of the hollow flap shaft 31 for the purpose of prolonging the residence time of the coolant. The cooling air delivered by the cooling-air fan 32 is introduced via a flexible line 33 into one end of the hollow shaft 31, and the cooling air heated in the flap 22 is discharged to the surroundings via the other end of the hollow shaft 31 via line 34. The pivoting flap 22 is actuated via an actuator 35, for example an electrical actuator having motor 36 and articulated spindle 37, or via hydraulic pivoting cylinder, pneumatic pivoting cylinder, etc. In any case, the cooled flap 22 of the hot-meal distributing device according to the invention, which is subjected to severe thermochemical and abrasive wear, is distinguished by a long service life.
An oscillating flap of an oscillating feeder or hot-meal downpipe, through which coolant flows, can be made similarly to the pivoting flap 22 of FIGS. 1 and 2, through which coolant flows.
The impingement gate 19 of FIG. 6 is detailed in FIGS. 3 to 5. In distinction to FIG. 6, the impingement gate 19 in FIG. 3 is built into the rotary-kiln off-gas line or riser 38 from the right side. The hot meal introduced via the meal line 18 is, on impinging on the impingement gate 19, uniformly distributed by said impingement gate over the entire cross section of the rotary-kiln off-gas riser. The impingement gate 19 is also made as a hollow body through which coolant flows, in the interior of which hollow body there is built-in at least one web arranged transverse to the gate plane, specifically two webs 39, 40 in the exemplary embodiment of FIG. 5, which webs divert the coolant, again cooling air in the exemplary embodiment, admitted via an inlet opening 41 arranged on the outer end face of the gate, to at least one coolant discharge opening likewise arranged on the outer end face of the gate, according to FIG. 5 to the discharge openings 42 and 43. The cooling air admitted via opening 41 to the hollow impingement gate 19 can be a high-velocity compressed air, which by the injector principle draws further quantities of air located in the vicinity into the hollow body from the surroundings and conveys said quantities of air through the hollow body for its cooling. The service life of the air-cooled impingement gate 19 of FIG. 3 is likewise very long.
The air-cooled impingement gate 19 can be built into not only the calcination zone of the rotary kiln off-gas line or riser 38 of the cement clinker production line, as shown in the example of FIG. 6, but also at another point of the cyclone suspension-type heat-exchanger system, for example in the off-gas line between the lowest and second-lowest cyclone, and so forth. | A cement plant for the production of cement clinker from cement raw meal has a flat plate shaped control element for distributing and/or transporting-feeding a stream of hot flour-like material which is subjected to severe thermochemical and abrasive ware. the service life of the control element is greatly increased by constructing it as a hollow body (19, 22) through which coolant flows from at least one inlet opening to at least one discharge opening. | 5 |
FIELD OF THE INVENTION
[0001] The present application claims priority U.S. Provisional Application Ser. No. 61/770,587, filed Feb. 28, 2013, herein incorporated by reference in its entirety.
[0002] The present invention relates to a wall panel, methods, and systems for its installation. More particularly, the present invention relates to a modular wall panel with improved physical characteristics, and methods and systems for its installation.
BACKGROUND
[0003] Finished or “club” basements are a common part of residential structures. Conventional wood framing has been widely used to achieve a finished wall surface. Recently the developments of other innovative wall finishing systems have emerged. These systems are comprised of “shape-molded” insulation panels such as: In-So-Fast™; R-Retro™; Re-Fit™ and BuildLock™. Owens Corning also markets fiberglass softwall systems whose use is common in residential settings. The wall finishing systems typically consist of some type of framework and/or studs into which modular wall panels are fitted.
[0004] The wall panels used in these finishing systems suffer from several drawbacks however, which make handling, fitting, and installation difficult. Many of the wall panels are too rigid, which makes cutting and handling of them difficult. Cutting the wall material often can damage saws which are used therein. Other wall panels are very light and easy to handle, but are also easily damaged in shipping and handling of the panel. Such panels also do not possess sufficient tensile strength to structurally serve as a wall, and are difficult to hang things thereupon.
[0005] Other wall panels are too heavy and are difficult to work with. Some heavier paneling requires specialized framework to accommodate the panels, and may be too heavy to be used in some framing systems. Additionally, most wall panels require a finishing step in order to make the finished wall cosmetically acceptable after installation. Some finishing steps include painting, wallpapering, or other type of procedure in order to make the newly installed wall acceptable in the home or office in which it was installed.
[0006] It is therefore desirable to provide a modular wall panel, and installation systems and methods which are easier to handle and install, are more environmentally friendly, and are more cosmetically acceptable.
SUMMARY
[0007] Provided therefore herein is a modular wall panel, and a system for installing and method of making thereof. The modular wall panel includes a first insulating layer made of an extruded polystyrene foam. The panel further includes a second rigid layer made of a closed cell polyvinylchloride foam board. A third finishing layer is further included in the panel, the third layer made of a cosmetically acceptable material for living conditions.
[0008] In an embodiment, the first layer of the modular wall panel is adhered to the second layer, and the second layer is adhered to the third layer in a sandwich configuration where the second layer resides between the first and third layer. In another embodiment, layers of the modular wall panel are adhered together by an adhesive selected from any water based contact adhesive.
[0009] In another embodiment, the first insulating layer of the modular wall panel is from about 3 centimeters to about 7 centimeters thick; and the second rigid layer is from about 3 millimeters to about 7 millimeters thick. In another embodiment, the first insulating layer is from about 4 centimeters to about 6 centimeters thick; and the second rigid layer is from about 4 millimeters to about 6 millimeters thick. In a preferred embodiment, the first insulating layer is about 5 centimeters thick and said second rigid layer is about 5 millimeters thick.
[0010] In yet another embodiment, the third finishing layer of the modular wall panel is formed of a material selected from the group of vinyl wall fabric coverings, rigid vinyl wall materials, wainscoting, or formica.
[0011] In yet another embodiment, a system of making or finishing a wall in an edifice is provided herein. The system includes providing a framework for supporting wall panels. Within the framework is inserted a modular wall panel. The modular wall panel includes a first insulating layer formed of an extruded polystyrene foam; a second rigid layer formed of a closed cell polyvinylchloride foam board; and a third finishing layer comprising a cosmetically acceptable material for living conditions.
DETAILED DESCRIPTION
[0012] FIG. 1 shows a blown-up cross section of a modular wall panel of the present invention.
[0013] FIG. 2 shows a front view of a modular wall panel of the present invention.
[0014] This structure of the panel of the present invention is comprised of three layers, and they have one dimension (their respective thicknesses) that is smaller than their other two respective dimensions. These plates are essentially planar; but they could be curved into two or three dimensions, developable or non-developable in the mathematical sense.
[0015] With reference to the Figures, the sandwich structure 10 therefore comprises a first insulating layer 12 made of extruded polystyrene foam, a second rigid layer 14 made of a closed cell PVC foamboard, and a third finishing layer 16 . Insulating layer 12 has a length 18 , and a width 20 , and a thickness 22 . Rigid layer 14 also has a length and width which are identical to insulating layer 12 as the layers form a sandwich structure. Finishing layer 16 also has a length and a width, which may be the same as insulating layer 12 and rigid layer 14 , but may be slightly longer in either dimension as it may be wrapped around a side of the panel if in fabric form.
[0016] In order to assemble, a framework is first established in an edifice in which the modular wall panel will be used. The framework can be placed against a perimeter wall of the edifice or an internal wall, and includes a rigid frame, which may be steel. It is an advantage of the present invention that the modular wall panels may be used with a variety of frames and materials. The size, i.e., length and width, of the modular wall panels may vary greatly depending on how it will be used. They may be used as squares; i.e., length equals width.
[0017] The framework may be installed by methods well known in the art. A steel frame is first installed, after which our panels are appended thereto, typically with screw fasteners. A PVC molding is optionally installed thereafter, including crown molding, chair rails, and other items. The modular wall panels may be easily replaceable, or updated at a later date.
[0018] First insulating layer 12 consists of extruded polystyrene foam (XPS), which consists of closed cells, offers improved surface roughness and higher stiffness and reduced thermal conductivity. The density range is about 28-45 kg/m 3 . Extruded polystyrene foam is commonly used as an insulator. Because of the extrusion manufacturing process, XPS does not require facers to maintain its thermal or physical property performance. Thus, it makes a more uniform substitute for corrugated cardboard. Thermal resistivity is usually about 35 m·K/W (or R-5 per inch in American customary units) but can range between 29 and 39 m·K/W depending on bearing/density. Thermal conductivity varies between 0.029 and 0.039 W/(m·K) depending on bearing strength/density and the average value is ˜0.035 W/(m·K). Water vapor diffusion resistance (μ) of XPS is typically around 80-250. While XPS is the preferred embodiment, it is recognized that other insulative layers may be substituted therefore without varying from the scope of the invention.
[0019] The second rigid layer 14 is made of closed-cell PVC foamboard. Closed-cell PVC foamboard is a light-weight rigid material used primarily in the manufacture of signs and displays, although its material properties have made it extremely popular among model makers, prop, composite experimental aircraft and yacht builders. Like PVC, closed-cell PVC foamboard is solid and has a very rigid structure. Where it differs is in its closed-cell foam structure, which makes it very light (as little as half the weight of solid PVC), highly resistant to moisture and some chemicals, and very easy to cut and shape. It also has thermoplastic properties, and begins to soften at around 65° C. Typically, closed-cell PVC foamboard can be cut as easily as wood, softened and shaped by immersing in boiling water or with a standard heat gun, and painted with standard automobile paints.
[0020] The third finished layer 16 may be a flexible fabric skin such as a fabric coated with a vinyl. A vinyl material that may be used for such a purpose is manufactured by USCAN, LLC of Merritt Island, Fla.; an example of such vinyl material is marketed under the trade name or identifier US 185-HC. This type of vinyl may be composed of a polyester base fabric with a PVC coating. It may have, for example, a thickness of 0.58 mm, a weight of 630 grams per square meter, and a temperature resistance of −30 to +70 degrees Celsius.
[0021] An adhesive is used to assemble the layers together. Preferred adhesives are water-based contact adhesives, which also benefit from being environmentally acceptable. A preferred adhesive is H2O from Wilson Art International®, which consists principally of polychlorprene, zinc oxide, water, Resin acid, and Rosin acid, in sodium and potassium form.
EXAMPLES
[0022] Example 1
[0023] In order to make the modular wall panel, XPS foam board is used, such as Greenguard® type IV cm square edge, 25 psi. The XPS board can have a thickness of 2 inches for foundation walls (with a R value of 10), or a thickness of 1 inch or ½ inch (R value of 5 and 2.5 respectively) when used as non-foundation walls. A PVC foamboard of 3 mm thickness from Laird Plastics® is also used in conjunction with vinyl wall coverings from Brewster Wall Coverings (15 oz or 20 oz vinyl).
[0024] In order to assemble the layer components, a water based adhesive, such as H2O from Wilson Art International®, is applied to one side of the XPS foam and one side of the PVC, then press laminated together. The adhesive is then applied to the PVC side of combined structure, as well as to the backside of vinyl wall covering, and press laminated together, which includes wrapping the vinyl and laminating to side of PVC foamboard. After assembly, the composite is trimmed to a rectangle.
[0025] It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. | Provided herein is a modular wall panel, and a system for installing and method of making thereof. The modular wall panel includes a first insulating layer made of extruded polystyrene foam. The panel further includes a second rigid layer made of a closed cell polyvinylchloride foam board. A third finishing layer is further included in the panel, the third layer made of a cosmetically acceptable material for living conditions. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for cutting mechanically interlocking joints, specifically tenons and mortises for wood and other wood-type materials. More specifically, the present invention provides an apparatus for cutting both mortise and tenon configured joints on one apparatus. Even more specifically, the present invention provides an apparatus for cutting angle tenon cuts in a work-piece as well as mitered tenon cuts in a work-piece.
In the joining of two pieces of wood and other wood-type materials, various types of joints are utilized. The most common types of joints are referred to as dowel pin joints, dado joints, "box-cut" joints, blind, half-blind, and open "dove-tail" joints at a 90° angle to form a box-like structure; and, "mortise" and "tenon" joints.
Generally, in the cutting of tenons, tenons have been cut using a table saw, radial saw or a router table and the cut has been pre-scribed on the work-piece to define the line of the desired cut. In a mortise cut, the outline of the cut has also been pre-scribed and a drill press has been the most common means for making the cut with a square chisel utilized to finish the desired pre-scribed cut. Thus, it has been common practice to utilize two different types of apparatuses to obtain both tenon and mortise cuts in joints for work-pieces of a box-cut configuration, particularly those useful in attachment of legs to chairs and tables in the furniture industry.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an apparatus for cutting a plurality of different sizes of tenon and mortise cuts in work-pieces which is portable and easy manipulated in cutting two work-pieces which are to be joined together.
Another object of the present invention is to provide an apparatus for cutting mating tenon and mortise cuts in work-pieces to be joined together.
A further object of the present invention is to provide an apparatus for cutting tenon and mortise pieces forming a box-like structure joint without the need for pre-scribing the outlines of the proposed cuts.
An even further object of the present invention is to provide an apparatus for making angle tenon cuts, miter tenon cuts, and open-end mortise cuts in work-pieces.
Also, an object of the present invention is to provide an apparatus for making mortise and tenon cuts which substantially reduces the mathematical calculations in determining the size and location of the cuts.
An object of the present invention is to provide an apparatus for making mortise and tenon cuts without the use of templates or other patterns.
Particularly, the present invention is directed to an apparatus for making tenon and mortise cuts in work-pieces comprising:
a table having a first opening in a top surface thereof;
a detachable support for holding a work-piece in a preselected position, said support being detachably connected to said table;
means for positioning said work-piece in said support;
a base assembly for a cutting means slidably mounted onto said support, said base assembly having a second opening therein to receive said cutting means therethrough, said second opening being adjustable and positionable in cutting relation with one end of said work-piece; and,
means to determine the size and location of said second opening and define the slidable movement of said base assembly on said table, said second opening size and location and the movability of said second opening defining the appropriate peripheral cutting boundaries on said end of said work-piece to be subjected to said cutting means.
These and other advantages of the present invention will become apparent to those skilled in the art upon reference to the following detailed description:
BRIEF DESCRIPTION OF THE DRAWINGS
The description refers to the accompanying drawings in which like parts are given like reference numerals and wherein:
FIG. 1 is an isometric view of a preferred apparatus of the present invention;
FIG. 2 is an exploded view of a sliding router base assembly of the preferred apparatus of FIG. 1;
FIG. 3 is an exploded view of a table of the preferred apparatus of FIG. 1;
FIG. 4 is an exploded view of a vertical work-piece holding assembly of the preferred apparatus of FIG. 1;
FIG. 5 is an isometric view of the table and vertical work-piece holding assembly of FIG. 1 including a work-piece with a tenon cut therein with the slider router base assembly being removed from the apparatus;
FIG. 6 is an isometric view of the table and vertical work-piece holding assembly of FIG. 1 with a work-piece in a mortise cut position with the sliding router base assembly removed from the apparatus.
FIG. 7 is a plan view of an X-direction movable scale member of the preferred embodiment;
FIG. 8 is a plan view of a Y-direction movable scale member of the preferred embodiment;
FIG. 9 is a plan view of a fixed X-direction scale member of the preferred embodiment;
FIG. 10 is a plan view of a fixed Y-direction scale member of the preferred embodiment;
FIG. 11 is an end view of the preferred embodiment positioned to make an angled tenon cut;
FIG. 12 is an elevational view of the preferred embodiment positioned to make a mitered tenon cut with selected portions of the work-piece holding assembly removed; and,
FIG. 13 is a perspective view of a selected section of the preferred embodiment showing an alignment of a work-piece in the preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As best seen in FIG. 1, the preferred embodiment of the apparatus of the present invention is designated by the numeral 10. The apparatus 10 includes a sliding router base assembly 12, a table 14 upon which the sliding router base assembly 12 is movable thereon and a work-piece holding assembly 16 which is mounted to the front of the table 14.
As best seen in FIG. 2, the sliding router base assembly 12 includes a sliding router base member 18 which is provided with an opening 46 therein to receive a router (not shown). The sliding router base 18 is provided with a movable flange portion 26 which is received within groove 28 (FIG. 3) of the table 14 for movement therein. The flange 26 is provided with an open ended slot 27 therein to receive the stop member holding and pivot rod 24 therethrough. Mounted to opposite ends of the pivot rod 24 are X-direction stop members 22a and 22b. The X-direction stop members 22a and 22b are utilized for stopping the movement of the sliding router base assembly 12 in an X-direction as will be discussed more fully hereinafter.
The sliding router base 18 is also provided with a recess 40 that runs longitudinally thereof and receives movable Y-directional stop members 42a, 42b and movable Y-directional router bushing repeat stop members 44a, 44b. The movable Y-directional stops 42a, 42b are provided with slots 43a, 43b therein which receive mounting bolts 52 therethrough. The mounting bolts 52, only one being shown for slot 43a, extend through the slots 43a, 43b, and are received by rotable clamping knobs 48a, 48b, respectively. Washers 54a, 54b may also be provided. The mounting bolts 52 in combination with rotatable clamping knobs 48a, 48b provide the means for loosening and tightening the Y-direction movable stop members 42a, 42b upon positioning as discussed hereinafter. The positioning of the Y-direction stop members 42a, 42b define the Y-directional movement of the router.
The movable Y-directional router bushing repeat stop members 44a, 44b are provided with slots 45a, 45b therein which receive mounting bolts 56 therethrough. The mounting bolts 56, only one being shown for slot 45a, extend through the slots 45a, 45b and are received by rotatable clamping knobs 50a, 50b, respectively. Washers 58a, 58b may also be provided. The mounting bolts 56 in combination with rotatable clamping knobs 50a, 50b provide the means for tightening and loosening stops 44a, 44b, as discussed hereinafter.
The sliding router base 18 is provided with a fixed Y-directional scale 34 and a magnetic movable Y-directional scale 30 which is received within the movable Y-directional scale receiving groove 32.
Since the sliding router base 18 is generally made from a material which is non-metallic, means must be provided to hold the magnetic Y-directional scale member 30 thereon. Thus, the groove 32 is provided with steel washer cutouts 33a, 33b for receiving steel washers 36a, 36b, respectively, therein. Vertically extending positioning posts 38a, 38b, respectively, are provided for receiving the steel washers 36a, 36b thereon. The cutouts 33a, 33b are substantially the same thickness as the washers 36a, 36b so that the surface of the groove 32 is flat and smooth for movably receiving the magnetic movable Y-directional scale member 30 therein.
As best seen in FIG. 3, the table 14 is provided with an opening 120 for receiving a router (not shown) therethrough. The back of the opening 120 is defined by a downwardly extending back wall 116 with a vacuum port 118 therein for removal of wood chips during the cutting operation. Sidewalls 117, which define the sides of the opening 120, only one sidewall 117 being exposed in FIG. 3, are provided for mounting a hook receiving plate member 134 therebetween. The hook receiving member 134 is provided with an upper edge 136 of arcuate configuration. The radius of curvature of upper edge 136 is such that upon receiving C-shaped hook 258, FIG. 4, of the work-piece holding assembly 16, the work-piece holding assembly 16 is rotatably mounted onto table 14.
The table 14 is provided with a groove 124 for receiving the sliding X-direction stop members 122a and 122b therein. The groove 124 is also provided with a pair of openings on opposite ends thereof (not shown) for receiving stop member mounting bolts 126a, 126b therethrough. The sliding X-directional stop members 122a, 122b are also provided with elongated slots 138a, 138b, respectively therein, to receive the bolts 126a, 126b therethrough. Washers 128a, 128b and rotatable clamping knobs 130a, 130b are provided for receiving the bolts 126a, 126b, respectively, therethrough. Loosening and tightening the clamping knobs 130a, 130b, provide for the means for the movement of the sliding X-directional stop members 122b, 122b within the groove 124. The sliding X-directional stop members 122a, 122b are also provided with stop edges 132a, 132b, respectively, wherein upon positioning of the sliding x-direction stop members 122a, 122b, the stop edges 132a, 132b define the X-directional movement of the sliding router base assembly 12.
The table 14 is also provided with an X-scale receiving groove 146 to receive the flexible magnet movable X-scale member 140. As noted previously, the apparatus 10 is generally made from a non-metallic material and therefore metal means for holding the flexible magnetic movable X-scale member 140 is required. As shown in FIG. 3, the groove 146 is provided with openings 143a, 143b for receiving metal screws 144a, 144b, respectively, therethrough for holding the magnetic scale 140 within the groove 146.
The table 14 is supported by a pair of legs 148a, 148b on opposite sides thereof. The legs 148a, 148b are provided with covers 150a, 150b, respectively, which are attached thereto by appropriate mounting bolts 151a, 151b, respectively. The leg housing 149a, includes a pair of openings 152a, 152c, and leg housing 149b includes a pair of openings 152b, 152d for receiving mounting bolts therethrough, only two openings being shown and identified by numerals 155a, 155b (FIGS. 1, 5 and 6). The mounting bolt openings 152a, b, c, d are in alignment with openings 156a, 156b in table brace support member 158a, and corresponding openings (not shown) in table brace support member 158b, as well as openings 154a, b, c, d, in table 14. The mounting bolts (not shown) extend through the aligned openings, for example 152a, with 156a, and 154a for attaching leg 148a to the table 14. On opposite sides of the table 14 are transversely extending grooves 157a and 157b for receipt of the table brace supports 158a and 158b therein.
Wedge adjusting bolts 160a and 160b are provided for positioning movable wedge work-piece holding member 168 (FIG. 4) in an angular position for making angle-cut tenons. The adjustable or movable wedge 168 is provided with wedge positioning slots 170 (FIG. 4), which receive the wedge positioning mounting bolts 160a, 160b, respectively, therethrough. The bolts 160a, 160b are mounted to the legs 148a, 148b through fixed sleeves which are unitary with the housings 149a, 149b and which extend transverse of the legs 148a, 148b, respectively. Only one sleeve 162 in housing 149a is shown. The threaded ends of the bolts 160a, 160b, extend through openings 163a, 163b, respectively, in the covers 150a, 150b, respectively, and are threadably received by rotatable adjusting knobs 166a, 166b with washers 164a, 164b, respectively, positioned between the knobs 166a, 166b, and the openings 163a, 163b. Adjusting knobs 166a, 166 b, are utilized for tightening and loosening the bolts 160a, 160b in relation to the wedge positioning slots 170, so the movable wedge member 168 may be positioned at preselected angles in relation to the table 14.
As shown in FIG. 4, the work-piece holding assembly 16 includes the movable wedge member 168 and a clamping assembly 218. The movable wedge 168 is provided with a wedge face 220 which receives the work-piece thereon with the work-piece being held thereto by a clamping bar 236 of the clamping assembly 218. The clamping bar 236 extends from each side of the wedge 168 and is held in place by two C-shaped clamps 226a, 226b. As best shown in FIGS. 5 and 6, the work-pieces 300, 302 are sandwiched between the clamping bar 236 and the wedge face 220.
As shown in FIGS. 3 and 4, the movable wedge 168 is provided with spaced opposed side members 169, only one being shown with slots 170 therein. On opposite sides of the wedge face 220 and adjacent to the side members 169, are a pair of vertically extending positioning slots 222a, and 222b. The slots 222a and 222b receive vertical adjusting bolts 224a and 224b, respectively, therethrough. Each of the C-shaped clamps 226a, 226b is provided with a fixedly mounted sleeve 228 therein which receive the bolts 224a, 224b therethrough. In alignment with the sleeve 228 is a rotatable position adjusting knob 230 which is attached to one end of each of the bolts 224a, 224b. Upon rotation of the knobs 230, the C-clamps 226a, 226b are either pulled towards the wedge face 220 or loosened therefrom. When the C-clamp 226a, 226b are loosened, the work-piece holding assembly 16 may be moved vertically and repositioned.
As best shown in FIG. 4, each C-shaped clamp 226a, 226b is provided with a sleeve 242 thereon to receive the threaded clamping bar adjusting bolt members 232. Clamping bar 236 is provided with openings 238a, 238b therethrough on each end thereof for alignment with the sleeve 242 for receiving the threaded bolt member 232 therethrough. One end of each threaded bolt member 232 is attached to a clamp handle 234 for rotatable movement of the threaded member 232. Upon mounting the C-shaped clamps 226a, 226b to the clamping bar 236 with the threaded bolt members 232, the end of the threaded bolt member 232 opposite the clamp handle 234 is received by an E-ring 240. The threaded bolt member 232 is also provided with a shoulder 244 which has a diameter greater than the diameter of the openings 238a, 238b so that the threaded portion 246 of the mounting bolt 232 extends through the openings 238a, 238b. By rotation of the mounting bolt 232, the clamping bar 236 is moved towards or away from the wedge face 220 thereby tightening or loosening the clamping assembly 218 grip on the work-pieces as shown in FIGS. 5 and 6.
The work-piece holding assembly 16 is also provided with a work-piece adjusting stop member 248 which is used to position the work-piece at a plurality of angles from horizontal to vertical. The work-piece positioning stop member 248 is provided with an alignment edge 250 which is positionable at selected angles on the wedge face 220 and upon which the work-piece 300, 302 rests when in a cutting position. The work-piece positioning stop member 248 is provided with a plurality of positioning pins 252 thereon. The work-piece positioning member 248 is provided with two pins 252 on a front face and two pins 252 on a back face so that either the front or back of the work-piece positioning member 248 may be used. The wedge face 220 is provided with a plurality of positioning pin receiving openings 254 for receiving either the positioning pins 252 on the front face or the positioning pins 252 on the back face therein. The positioning stop member 248 can be positioned at a varying number of angles from vertical to horizontal depending upon the type of tenon cut desired. The stop member 248 may be turned over so that either pair of pins 252 may be utilized, depending upon the preselected angle desired for cutting a tenon in a work-piece. When using pins 252 on the back, an aligning edge 251 is also provided on the opposite side of the work-piece positioning stop member 248 from aligning edge 250.
FIGS. 7 and 8 are details of the two magnetic movable scales 140 and 30, respectively, used in the aligning and positioning of sliding X-direction stop member 122a, 122b and sliding Y-direction stop members 42a, 42b and 44a, 44b. In FIGS. 7 and 8, the scales 140 and 30 are shown at a reduction of their actual scale. For example, in the making of a mortise and tenon joint cut for a joint utilizing a 3/8" drill bit, a work-piece 300 for the tenon cut is positioned in the apparatus 10 as shown in FIG. 5 with the center point of the piece to be cut identified by the "X" in the center of the tenon cut. (The "X" is inscribed prior to the cut, but for illustration purposes, in FIG. 5, the "X" center point is shown after the cut.) Generally, the work-piece is positioned against work-piece stop member 248, and then the center-line 400 of the slidable scale 140 is lined up on the inscribed "X" For a 2" length cut, for example, the sliding X-direction stop members 122a and 122b are moved so that the stop edges 132a and 132b line up with the 1" mark on the movable scale 140 as noted by numerals 402a and 402b. Clamping knobs 130a and 130b for the sliding X-directional stop members 122a and 122b are tightened so that the movable stop members 122a and 122b are held securely in place. When moving the sliding router base assembly 12 in the X-direction, upon engagement with the X-directional stop edges 23a, 24b, stop members 22a, 23b on the sliding router base assembly 12 prevent further movement of the router in the X-direction.
Table 14 of apparatus 10 is also provided with the fixed X-scale member 142 which is also used for aligning the center-line of the movable scale 140 wherein the centering of the work-piece has not been pre-scribed as discussed previously. In this example, the "O" point of the scale member 142, as noted by the numeral 142a in FIGS. 5 and 9, is always lined up with the edge 300b (FIG. 5) and edge 250 (FIG. 4). The distance between edge 300b and the desired center-point of the cut is determined and the center-line 400 of the movable scale 140 (FIG. 7) is lined up with the terminating end of this defined distance. Thus, since the center line 400 is positioned in alignment with the center point, then the positioning of the X-stop members will be determined as discussed previously for a work-piece having a prescribed "X".
The movable Y-scale member 30 is positioned so that the center line 500 is lined up with the "X" on the work-piece as shown in FIG. 5. For a 3/8" drill, the stop edges 47a, 47b on the movable Y-stop members 42a, 42b, respectively, are positioned with the stop edges 47a and 47b being located at the 3/16" position on the scale 30 as noted by numerals 502a and 502b in FIG. 8. Also, stop edges 49a and 49b are aligned with the 502a, 502b position, respectively, on the 502 tenon scale. Clamping knobs 48a, 48b and 50a, 50b, are then tightened so that the movable stops 42a, 42b, 44a, 44b are held securely in place in the recess 40. Once all of the stop members are secured, a router is then placed within the elongated opening 46, opening 46 having a width approximately equal to the diameter of a router bushing. Therefore, the router bushing moves in a Y-direction only and the entire sliding base 18 moves in an X-direction for making the cut.
The sliding router base assembly 12 is also provided with the fixed Y-scale member 34 which is also used for aligning the center-line of the movable scale 30 wherein the centering of the work-piece has not been inscribed as discussed previously. In this situation, the "O" point of the scale member 34, as noted by the numeral 34a in FIGS. 5 and 10 is lined up with the edge 300a (FIG. 5) and wedge face 220 (FIG. 4). The distance between edge 300a and the desired center-point of the cut is determined and the center-line 500 of the movable scale 30 (FIG. 8) is lined up with the terminating end of this defined distance. Thus, since the center-line 500 is positioned in alignment with the center-point, then the positioning of the Y-stop members will be determined as discussed previously for a work-piece having a prescribed "X".
Even though the work-piece 300 as shown in FIG. 5 is positioned for a regular tenon cut, it is realized that the work-piece positioning stop member 248 may be positioned so that the positioning pins 252 are inserted into positioning pin receiving openings 254 at a desired preselected angle so that the work-piece 300 may be cut at angles of less than 90° to the table 14.
Also, the work-piece 300 as shown in FIG. 5 may be positioned for an angled tenon cut. In positioning the work-piece 300 for an angled tenon cut, the movable wedge member 168 is positioned, as discussed previously and shown in FIG. 11, to the desired angle in relation to the table 14.
Furthermore, the X-directional stop members 22a and 22b are pivotably attached to the sliding router base 18 so that when removing material from outside a tenon cut greater than the diameter of the drill bit, such as 3/8", the stop members 22a and 22b can be pivoted upward so that the router can be moved further in the X-direction with a second pass around the work-piece.
Also, in the making of the second pass, the Y-directional stop members 42a, 42b are loosened for slidable movement with the router and the Y-direction router bushing repeat stop members 44a, 44b remain stationary. The stop members 42a, 42b are provided with mating L-shaped tab portions 192a, 192b, respectively, which are configured for mating with co-operating L-shaped tab portion 194a, 194b, respectively, on stop members 44a, 44b. In making the second pass, the movable stop members 42a, 42b move with the router in the Y-direction and upon completion of the second pass the L-shaped tab portion 192a, 192b prevent further movement in the Y-direction upon engagement with the L-shaped tab portions 194a, 194b, respectively. Positioning of the repeat stop members 44a, 44b enable re-producability of multiple cuts of the same shape and dimension.
As shown in FIG. 6, the work-piece 302 is positioned for a mortise cut as identified by the illustrated finished cut 304. In the use of the movable scales 140, 30 as shown in FIGS. 7 and 8 for a mortise cut, the center portion of the cut is determined in the same manner as that for a tenon cut in FIG. 5 as designated by an "X" thereon. For the mortise cut, the center line 400 of movable scale 140 is lined up with the center of the "X" and the sliding X-directional stop members 122a and 122b are moved so that the stop edge 132a is located at the 1" position noted by the numeral 406a and the stop edge 132b, of sliding X-directional stop member 122b is located at the position noted by the numeral 406b. Clamping knobs 130a and 130b are then tightened so that the movable sliding X-directional stop members 122a, 122b are held securely in place.
As shown in FIG. 13, the work-piece positioning stop 248 is provided with one longitudinally extending side 251a including edge 251 which is equal to the width of opening 120. Insertion of side 251a into opening 120 and aligning this side 251a with the center-line 400 of the movable X-scale 140 enables the alignment of subsequent work-pieces 302 to be cut accordingly.
The movable scale 30 is then located with the center line 500 lined up with the "X" on the work-piece. The movable Y-directional stop members 42a, 42b are then positioned so that the stop edges 47a, 47b, respectively, are located at the positions as noted by numerals 504a, 504b, respectively, on the 504 scale of the movable Y-directional scale 30 (FIG. 8). Stop edges 49a, 49b of Y-directional bushing repeat stop members are also located at the positions 504a, 504b, respectively, on the movable scale 30. Appropriate clamping knobs 48a, 48b and 50a, 50b are then rotated in a tightening position so that the stop members 42a, 42b and 44a, 44b are secured within the recess 40. Upon insertion of the router into the opening 46 in recess 40, the router may then be moved in the X-Y-direction as necessary in cutting the mortise as shown in FIG. 6 and identified by the numeral 304.
It is realized that varying and different embodiments may be made within the scope of the inventive concept herein described because many modifications may be made to the embodiments herein detailed, but it is to be understood that the details herein are to be interpreted as shown and not to be unduly restrictive of the present invention. | An apparatus for making tenons and mortises includes a table with a first opening in the top surface thereof. The top surface is disposed for receiving a sliding base assembly for a cutting device having a second opening therein. A work-piece holding assembly is detachably connected to a front portion of the table. The table and sliding base assembly cooperate to define the movement of the sliding base assembly in relation to said first opening. The work-piece holding assembly is positionable at preselected angles and varying vertical positions in relation to the top surface of the table. | 1 |
This nonprovisional application is based on Japanese Patent Application No. 2005-219490 filed with the Japan Patent Office on Jul. 28, 2005, the entire contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to optical pickup devices and particularly to optical pickup devices optically recording information on and reproducing information from a plurality of different types of recording media having guide grooves, respectively, different in pitch.
2. Description of the Background Art
In recent years, optical disks, optical cards and similar recording media can record large amounts of information signals densely and are accordingly utilized in audio equipment, video equipment, computers and other equipment.
Recently, in particular, for motion video information and the like used for example in computers, the data that are handled are drastically increasing in amount. Accordingly, a recording pit reduced in size, a guide groove reduced in pitch and the like are provided to provide optical disks with large capacities.
The above described optical disks and similar recording media have an information signal recorded therein in microns. Accordingly, reproducing such signal therefrom entails causing a beam of light to track a recording guide groove precisely. A variety of methods of detecting a tracking error signal is known.
For example, Japanese Patent Laying-Open No. 61-094246 describes a differential push-pull (DPP) method employing three beams including a main beam and two sub beams. The DPP method is generally employed for a variety of recording optical disks including compact disk-recordable/rewritable (CD-R/RW).
The DPP method, however, requires that relative to a guide groove at which the main beam is positioned, the sub beams be positioned offset in the radial direction of an optical disk by ½ of the pitch of the guide groove. This provides a tracking error signal degraded for a different type of optical disk having a guide groove different in pitch.
As a means for resolving such problem, Japanese Patent Laying-Open No. 09-081942 proposes a method, as will be described hereinafter with reference to FIGS. 11-14 .
FIG. 11 schematically shows a structure of an optical system of a conventional optical pickup device 100 .
With reference to the figure, optical pickup device 100 includes a semiconductor laser 1 , a collimator lens 2 , a diffraction grating 300 A, a beam splitter 4 , an objective lens 5 , a condenser lens 7 , and a photoreceptive unit 8 including photoreceptive elements 8 A- 8 C each divided into two regions. Optical pickup device 100 records information on and reproduces information from an optical disk 6 having a guide groove 61 .
Semiconductor laser 1 emits a beam of light 30 P which is received by collimator lens 2 and collimated thereby. The collimated light is divided by diffraction grating 300 A serving as an optical branching element into a main beam 30 for recording and reproduction and detecting a servo signal and two sub beams 31 and 32 for tracking. The three beams 30 - 32 are transmitted through beam splitter 4 and condensed by objective lens 5 on a recording medium or optical disk 6 at guide groove 61 .
The three beams of light 30 - 32 are reflected and again transmitted through objective lens 5 , reflected by beam splitter 4 and incident through condenser lens 7 on the three photoreceptive elements 8 A- 8 C, respectively, which detect a push pull signal MPP of main beam 30 and push pull signals SPP 1 and SPP 2 of sub beams 31 and 32 , respectively. Optical pickup device 100 , as well as the conventional DPP method, obtains a tracking error signal TR by the following operation:
TR=MPP−k ·( SPP 1 +SPP 2),
wherein k represents a coefficient correcting a difference in quantity of light between main beam 30 and sub beams 31 and 32 . Furthermore, k·(SPP 1 +SPP 2 ) will also be indicated as a composite sub beam push pull signal SPP.
The conventional optical pickup device 100 shown in FIG. 11 is characterized by a periodical structure that diffraction grating 300 A has. This feature will now be described with reference to FIGS. 12-14 .
FIG. 12 is a perspective view of the structure of diffraction grating 300 A in optical pickup device 100 shown in FIG. 11 .
As shown in FIG. 12 , diffraction grating 300 A is divided into a first region 300 a and a second region 300 b by a line extending in a direction Y corresponding to that of guide groove 61 of optical disk 6 . These regions each have a structure having a protrusion and a depression extending in a direction X perpendicular to that of guide groove 61 and periodically repeated such that the periodical structures have phases, respectively, different from each other by 180°.
FIG. 13 shows a position of main beam 30 and sub beams 31 and 32 condensed on optical disk 6 at guide groove 61 for optical pickup device 100 shown in FIG. 11 .
As shown in FIG. 13 , sub beams 31 and 32 diffracted by the periodical structure of diffraction grating 300 A each have on optical disk 6 at guide groove 61 an optical phase difference of 180° in a half thereof. Consequently, sub beam 31 is divided into spots of condensed light 31 m and 31 n and sub beam 32 is divided into spots of condensed light 32 m and 32 n. Sub beams 31 and 32 each thus form spots of condensed light having two peaks, respectively, in intensity.
FIG. 14 represents in waveform push pull signals MPP, SPP, SPP 1 , SPP 2 corresponding to a structure of optical disk 6 for optical pickup device 100 shown in FIG. 11 .
As shown in the figure, sub beams 31 and 32 provide push pull signals SPP 1 and SPP 2 180 20 out of phase with push pull signal MPP of main beam 30 . Similarly, composite sub beam push pull signal SPP has a waveform 180° out of phase, in opposite phase, with push pull signal MPP of main beam 30 .
As such if sub beams 31 and 32 are positioned on the same guide groove 61 as main beam 30 , as shown in FIG. 13 , tracking error signal TR as intended is obtained. Optical pickup device 100 shown in FIG. 11 can thus accommodate a different type of optical disk having a guide groove different in pitch from optical disk 6 .
The above described DPP system, however, has a significant disadvantage in practical use. Currently increasingly used digital versatile disks (DVDs) include DVD-R/RW (having a storage capacity of 4.7 GB and a guide groove with a pitch of 0.74 μm), DVD-Random Access Memory (DVD-RAM) 1 (having a storage capacity of 2.6 GB and a guide groove with a pitch of 1.48 μm), DVD-RAM 2 (having a storage capacity of 4.7 GB and a guide groove with a pitch of 1.23 μm), and the like.
If such a variety of DVDs is subjected to the system disclosed in Japanese Patent Laying-Open No. 09-081942, and objective lens 5 shifts in a direction (X) orthogonal to guide groove 61 of optical disk 6 , then, tracking error signal TR would significantly be reduced in amplitude as compared with that provided in the conventional DPP method. Such reduction in amplitude is significant particularly for DVD-RAM 1 , DVD-RAM 2 , and other similar disks having guide grooves large in pitch.
An arithmetic circuit, a control circuit and the like for tracking error signal TR receives a signal, which in general is limited in how it varies in amplitude, and if tracking error signal TR significantly varies in amplitude as the objective lens shifts, optical pickup device 100 is significantly reduced in range of practical use.
The above disadvantage is resolved by a method, as disclosed in Japanese Patent Laying-Open No. 2004-145915. The publication describes an optical pickup device basically identical to the optical system of optical pickup device 100 shown in FIG. 11 except that diffraction grating 300 A serving as an optical branching element is replaced with a diffraction grating 300 B having a feature as will be described hereinafter with reference to FIG. 15 .
FIG. 15 is a perspective view of a structure of diffraction grating 300 B serving as another example of diffraction grating 300 A in optical pickup device 100 of FIG. 11 .
As shown in the figure, diffraction grating 300 B has constantly periodically repeated grating grooves formed therein and is divided into at least three regions, i.e., first, second and third regions 300 a , 300 b and 300 c , by a line extending in a direction (Y) orthogonal to that of the grating grooves.
While the second region 300 b has a periodical structure with a phase similarly as described for diffraction grating 300 A of Japanese Patent Laying-Open No. 09-081942, i.e., 180° out of phase with the first region 100 a , the third region 300 c intermediate between the first and second regions 300 a and 300 b is structured to be 90° out of phase with the first region 300 a.
Diffraction grating 300 B thus structured can also prevent tracking error signal TR significantly reduced in amplitude as the objective lens shifts for example for DVD-RAM 1 and DVD-RAM 2 having guide grooves with large pitches. Optical pickup device 100 can thus be increased in range of practical use.
Japanese Patent Laying-Open No. 2004-145915 describes that diffraction grating 300 B divided in three has each region having a periodical structure with a phase offset by an amount limited to 90° and 180°.
If a diffraction grating has a periodical structure positionally offset between adjacent regions to add a phase difference to diffracted light (or a sub beam), the diffraction grating, having a limited number of grating lines providing protrusions and depressions, cannot provide accurate phase variation at a boundary region. In that case, there is also caused unwanted high-order diffracted light, and hence reduced efficiency in utilization of light and unwanted light acting as noise. Accordingly, achieving an object with a minimized phase difference is desired.
Furthermore, diffraction grating 300 B that has regions having the periodical structure with their respective phases offset by amounts limited to 180° and 90° has the intermediate or third regions 300 c limited in optimum width and hence a reduced degree of freedom in design. Japanese Patent Laying-Open No. 2004-145915 is silent on a combination of phase offsets other than other than 180° and 90°, and any relationship between the direction of the grating grooves of the diffraction grating and a phase difference given.
SUMMARY OF THE INVENTION
The present invention contemplates an optical pickup device that can also minimize that degradation in amplitude of a tracking error signal which is caused as an objective lens shifts for a plurality of types of optical disks having guide grooves, respectively, different in pitch despite a diffraction grating divided into multiple regions provided with phases, respectively, offset by a reduced amount.
The present invention is an optical pickup device having a laser as a source of light emitting light in turn branched via an optical branching element into at least three beams of light including a main beam and two sub beams in turn condensed via an objective lens on an optical recording medium at a guide groove and reflected by the optical recording medium to provide three reflections of light in turn received by different detectors, each divided into two regions, respectively, to obtain a differential signal from the detectors to generate a tracking error signal from the differential signal, the optical branching element being a diffraction grating divided into at least three regions including a first region, a second region and a third region located intermediate between the first and second regions, the first, second and third regions having a periodical structure with their respective phases different from each other, the periodical structure having grating grooves in a direction determined depending on the phase of the second region to incline relative to a direction perpendicular to the guide groove of the optical recording medium.
Preferably, if relative to the first region the second regions has a phase difference α in degrees, on the optical recording medium the main beam and the sub beams have a distance L therebetween, and the optical recording medium has the guide groove with a pitch M, then the optical branching element has the periodical structure with the grating grooves in a direction inclined relative to the direction perpendicular to the guide groove of the optical recording medium by an angle θ=((180−α)/360)tan −1 (M/L).
Preferably the second region has the phase difference α of at least 30° and at most 180°.
Preferably the third region is provided with a phase difference of approximately ½ of the phase difference α of the second region.
Preferably the third region is further divided into at least two regions each having a different phase difference smaller than the phase difference α of the second region.
Preferably the third region has a phase smoothly varying from that of the periodical structure of the first region to that of the periodical structure of the second region.
Preferably the third region has the periodical structure of the first region and that of the second region alternately.
In accordance with the present invention, if a diffraction grating divided into multiple regions provided with phases, respectively, offset by a reduced amount, there can be provided a tracking error signal that is not degraded for a plurality of types of optical disks having guide grooves, respectively, different in pitch, and the signal can also be prevented from significantly reducing in amplitude as the objective lens shifts.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 schematically shows a configuration of an optical system of an optical pickup device 10 in a first embodiment of the present invention.
FIG. 2 is a perspective view of a structure of a diffraction grating 3 A in optical pickup device 10 of FIG. 1 .
FIG. 3 shows a periodical structure of diffraction grating 3 A in optical pickup device 10 of FIG. 1 .
FIG. 4 shows a position of a main beam 30 and sub beams 31 and 32 condensed on a optical disk 6 at a guide groove 61 for optical pickup device 10 of FIG. 1 .
FIG. 5 represents push pull signals MPP, SPP, SPP 1 , SPP 2 in waveform corresponding to a structure of optical disk 6 before diffraction grating 3 A is rotated by an angle θ.
FIG. 6 represents push pull signals MPP, SPP, SPP 1 , SPP 2 in waveform corresponding to the structure of optical disk 6 after diffraction grating 3 A is rotated by angle θ.
FIG. 7 represents for optical pickup device 10 of FIG. 1 a characteristic of tracking error signal TR in how it varies in amplitude for optical disk 6 provided in a variety of DVDs.
FIGS. 8 , 9 and 10 show periodical structures of diffraction gratings 3 B, 3 C and 3 D in first, second and third exemplary variations, respectively, of the first embodiment of the present invention.
FIG. 11 schematically shows a configuration of an optical system of a conventional optical pickup device 100 .
FIG. 12 is a perspective view of a structure of diffraction grating 300 A in optical pickup device 100 of FIG. 11 .
FIG. 13 shows a position of main beam 30 and sub beams 31 and 32 condensed on optical disk 6 at guide groove 61 for optical pickup device 100 of FIG. 11 .
FIG. 14 represents push pull signals MPP, SPP, SPP 1 , SPP 2 in waveform corresponding to a structure of optical disk 6 for optical pickup device 100 of FIG. 11 .
FIG. 15 is a perspective view of a structure of diffraction grating 300 B serving as another example of diffraction grating 300 A in optical pickup device 100 of FIG. 11 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter an embodiment of the present invention will now be more specifically described with reference to the drawings. Note that in the figures, identical or like components are identically denoted and will not be described repeatedly.
First Embodiment
FIG. 1 schematically shows a configuration of an optical system of an optical pickup device 10 in a first embodiment of the present invention.
As shown in FIG. 1 , the first embodiment provides optical pickup device 10 different from optical pickup device 11 of FIG. 11 in that diffraction grating 300 A serving as an optical branching element is replaced with a diffraction grating 3 A. Accordingly, the components that overlap FIG. 11 will not be described repeatedly.
FIG. 2 is a perspective view of a structure of diffraction grating 3 A in optical pickup device 10 of FIG. 1 .
As shown in the figure, the first embodiment provides diffraction grating 3 A divided into first, second and third regions 3 a , 3 b and 3 c by a line having a direction perpendicular to that of its grating grooves, with each region having a structure having a protrusion and a depression which extend in a direction inclined relative to a direction X by an angle θ and are periodically repeated. In other words, the first embodiment provides diffraction grating 3 A having grating grooves in a direction inclined by angle θ relative to directions X and Y. This will furthermore specifically be described with reference to FIG. 3 .
FIG. 3 shows the periodical structure of diffraction grating 3 A in optical pickup device 10 of FIG. 1 .
As shown in the figure, the first embodiment provides diffraction grating 3 A, by way of example, having the second region 3 b with its periodical structure 120° out of phase with the first region 3 a , and the third region 3 c intermediate between the first and second regions 3 a and 3 b with its periodical structure 60° out of phase with the first region 3 a.
Furthermore, if a direction corresponding to that of guide groove 61 of optical disk 6 is represented as direction Y and a direction perpendicular thereto is represented as direction X, then diffraction grating 3 A has grating grooves set in a direction inclined relative to directions X and Y by angle θ.
FIG. 4 . shows a position of a main beam 30 and sub beams 31 and 32 condensed on optical disk 6 at guide groove 61 for optical pickup device 10 of FIG. 1 .
As shown in the figure, sub beams 31 and 32 diffracted by the periodical structure of diffraction grating 3 A each have on optical disk 6 at guide groove 61 an optical phase difference at a portion thereof. Consequently, sub beam 31 is divided into spots of condensed light 31 a and 31 b and sub beam 32 is divided into spots of condensed light 32 a and 32 b . Sub beams 31 and 32 each thus form spots of condensed light providing two peaks in intensity.
With reference to FIG. 4 , if relative to the first region 3 a the second region 3 b has a phase difference represented by α (in degrees), on optical disk 6 main beam 30 and sub beams 31 and 32 have a distance therebetween represented by L (in μm), and optical disk 6 has guide groove 61 with a pitch represented by M (in μm), then angle θ is defined by:
θ=((180−α)/360)tan −1 (M/L) (1).
Distance L on optical disk 6 between main beam 30 and sub beams 31 and 32 depends on the optical system of interest. For example, if L=15 μm and a DVD-R/RW has a guide groove with a pitch M=0.74 μm, then, for α=120° as shown in FIG. 3 , diffraction grating 3 A has an inclination or angle θ=0.47°. This allows optical pickup device 10 of the first embodiment to provide tracking error signal TR invariable in amplitude and hence a completely equivalent signal for the DVD-R/RW, similarly as provided in the conventional DPP method.
Main beam 30 provides push pull signal MPP and sub beams 31 and 32 provide push pull signals SPP 1 , SPP 2 , SPP, as will be described hereinafter.
FIG. 5 represents push pull signals MPP, SPP, SPP 1 , SPP 2 in waveform corresponding to a structure of optical disk 6 before diffraction grating 3 A is rotated by angle θ.
FIG. 5 represents push pull signals MPP, SPP, SPP 1 , SPP 2 in waveform provided when relative to the first region 3 a the second region 3 b has phase difference α. If the second region 3 b has grating grooves +α out of phase with those of the first region 3 a , sub beam 31 (or a first-order, positive, diffracted beam of light) has an optical phase difference of +α added thereto and sub beam 32 (or a first-order, negative, diffracted beam of light) has an optical phase difference of −α added thereto.
Accordingly, if diffraction grating 3 A has grating grooves in a direction matching that perpendicular to guide groove 61 of optical disk 6 , as assumed as shown in FIG. 5 , then the first-order, positive, diffracted beam of light provides push pull signal SPP 1 +α out of phase with push pull signal MPP of the main beam and, in contrast, the first-order, negative, diffracted beam of light provides push pull signal SPP 2 −α out of phase therewith.
In the above described case, as shown in FIG. 5 , push pull signals SPP 1 and SPP 2 added together, i.e., composite sub beam push pull signal SPP, reduces from a maximum amplitude. Accordingly, diffraction grating 3 A is rotated around an optical axis (or an axis Z) to have its grating grooves in a direction inclined relative to direction X by angle θ to maximize composite sub beam push pull signal SPP in amplitude for optical disk 6 (e.g., DVD-R/RW).
FIG. 6 represents push pull signals MPP, SPP, SPP 1 , SPP 2 in waveform corresponding to the structure of optical disk 6 after diffraction grating 3 A is rotated by angle θ.
As shown in the figure, rotating diffraction grating 3 A by angle θ allows push pull signal SPP 1 to have a waveform (180−α) out of phase and push pull signal SPP 2 to have a waveform—(180−α) out of phase. This can provide composite sub beam push pull signal SPP similar to that provided in the conventional DPP method.
FIG. 7 represents for optical pickup device 10 of FIG. 1 a characteristic of tracking error signal TR in how it varies in amplitude for optical disk 6 provided in a variety of DVDs. In the figure, the horizontal axis represents an amount, as represented in micrometers, of shifting an objective lens, and the vertical axis represents tracking error amplitude (in relative value, as represented in %).
The relative value as represented along the vertical axis represents a relative value of a variation in amplitude with reference to an amplitude of tracking error signal TR provided in the system of Japanese Patent Laying-Open No. 09-081942 when an objective lens has a shift of zero. Such value was obtained for DVD-RAM 1 (having a guide groove with a pitch of 1.48 μm), DVD-RAM 2 (having a guide groove with a pitch of 1.23 μm) and a DVD-R/RW (having a guide groove with a pitch of 0.74 μm).
With reference to FIG. 7 , curves A 1 and A 2 represent variations in amplitude in the system of Japanese Patent Laying-Open No. 09-081942 for DVD-RAM 1 and DVD-RAM 2 , respectively. Curves A 3 and A 4 represent variations in amplitude in the system of the first embodiment of the present invention for DVD-RAM 1 and DVD-RAM 2 , respectively. A curve A 5 represents a variation in amplitude for the DVD-R/RW, which is substantially the same characteristic between the system of Japanese Patent Laying-Open No. 09-081942 and that of the first embodiment.
As shown in FIG. 7 , the system of the first embodiment (curves A 3 and A 4 ), as compared with that of Japanese Patent Laying-Open No. 09-081942, can also significantly prevent tracking error signal TR from having an amplitude varying increasingly/decreasingly for DVD-RAM 1 and DVD-RAM 2 having guide grooves with large pitches as the objective lens shifts. Although curves A 3 and A 4 show amplitude smaller in absolute value than curves A 1 and A 2 , increasing in gain for example by a signal generation circuit or the like allows them to be used without problem.
In the above description diffraction grating 3 A has relative to the first region 3 a the second region 3 b with a phase difference of 120° and the third region 3 c with that of 60°. However, it is not limited to such a combination of phase differences; it is similarly effective with combinations for example of: 60° and 30°; 90° and 45°; and the like.
It should be noted, however, that if relative to the first region 3 a the second region 3 b has phase difference α reduced in absolute value, and a DVD-RAM having a guide groove with a large pitch is subjected to reproduction, the tracking error signal is significantly degraded in amplitude as the objective lens shifts. Accordingly, desirably, phase difference α is set in a range of 30°≦α≦180°.
The first embodiment can thus provide diffraction grating 3 A having regions with their respective phases having a difference appropriately set, and rotated by angle θ to significantly prevent tracking error signal TR from having an amplitude varying increasingly/decreasingly as the objective lens shifts.
First Exemplary Variation of First Embodiment
Optical pickup device 10 of the first embodiment shown in FIG. 1 with diffraction grating 3 A serving as an optical branching element replaced with a diffraction grating 3 B will now be described as a first exemplary variation with reference to FIG. 8 .
FIG. 8 shows a periodical structure of diffraction grating 3 B in the first exemplary variation of the first embodiment of the present invention.
As shown in the figure, the first exemplary variation provides diffraction grating 3 B divided into first, second and third regions 3 a , 3 b and 3 d by a line having a direction perpendicular to that of its grating grooves, with each region having a structure with a protrusion and a depression that extend in a direction inclined relative to direction X by angle θ and are periodically repeated.
The first exemplary variation provides diffraction grating 3 B having the third region 3 d located intermediate between the first and second regions 3 a and 3 b and further divided in two to provide regions 3 d 1 and 3 d 2 . If a direction corresponding to that of guide groove 61 of optical disk 6 is represented as direction Y and a direction perpendicular thereto is represented as direction X, then the first exemplary variation provides diffraction grating 3 B having grating grooves set in a direction inclined relative to directions X and Y by angle θ, similarly as has been described for diffraction grating 3 A with reference to FIG. 3 .
The first exemplary variation provides diffraction grating 3 B, by way of example, having the second region 3 b having a periodical structure 120° out of phase with the first region 3 a , and the third region 3 d with regions 3 d 1 40° out of phase with the first region 3 a and region 3 d 2 80° out of phase with the first region 3 a . If diffraction grating 3 B has the second region 3 b out of phase by an amount α, then diffraction grating 3 B has region 3 d 1 set to be out of phase by an amount of α/3 an region 3 d 2 set to be out of phase by an amount of 2α/3.
While FIG. 8 shows the third region 3 d divided in two by way of example, the region is not limited to division in two and may be divided in n and have a phase offset added stepwise, wherein n is an integer of at least 2. In that case, providing regions successively adjacent to the first region 3 a such that they are successively out of phase by an amount of α/(n+1) will suffice. Thus dividing the third region 3 d into multiple regions each having a phase offset by an amount added stepwise can also be as effective as or more effective than the first embodiment.
Second Exemplary Variation of First Embodiment
Optical pickup device 10 of the first embodiment shown in FIG. 1 with diffraction grating 3 A serving as an optical branching element replaced with a diffraction grating 3 C will now be described as a second exemplary variation with reference to FIG. 9 .
FIG. 9 shows a periodical structure of diffraction grating 3 C in the second exemplary variation of the first embodiment of the present invention.
As shown in the figure, the second exemplary variation provides diffraction grating 3 C divided into first, second and third regions 3 a , 3 b and 3 e by a line having a direction perpendicular to that of its grating grooves, with each region having a structure with a protrusion and a depression that extend in a direction inclined relative to direction X by angle θ or an angle (θ−Δ) and are periodically repeated.
The second exemplary variation provides diffraction grating 3 C having the third region 3 e located intermediate between the first and second regions 3 a and 3 b . The third region 3 e has a structure with a protrusion and a depression periodically repeated and adjacent to both those of the structure of the first region 3 a and those of the structure of the second region 3 b . Consequently, diffraction grating 3 C has the third region 3 e different in inclination from the first and second regions 3 a and 3 b . If a direction corresponding to that of guide groove 61 of optical disk 6 is represented as direction Y and a direction perpendicular thereto is represented as direction X, then the second exemplary variation provides diffraction grating 3 C having grating grooves set in a direction inclined relative to directions X and Y by angle θ, similarly as has been described for diffraction grating 3 A with reference to FIG. 3 .
As has been described above, the second exemplary variation can provide diffraction grating 3 C including the third regions 3 e having a structure with a protrusion and a depression periodically repeated and adjacent to both those of the structure of the first region 3 a and those of the structure of the second region 3 b . Diffraction grating 3 C thus structured corresponds to diffraction grating 3 B described in the first exemplary variation that has the third region 3 d divided in n increased indefinitely. This example is also as effective as or more effective than the first embodiment.
Third Exemplary Variation of First Embodiment
Optical pickup device 10 of the first embodiment shown in FIG. 1 with diffraction grating 3 A serving as an optical branching element replaced with a diffraction grating 3 D will now be described as a third exemplary variation with reference to FIG. 10 .
FIG. 10 shows a periodical structure of diffraction grating 3 D in the third exemplary variation of the first embodiment of the present invention.
As shown in the figure, the third exemplary variation provides diffraction grating 3 D divided into first, second and third regions 3 a , 3 b and 3 f by a line having a direction perpendicular to that of its grating grooves, with each region having a structure with a protrusion and a depression that extend in a direction inclined relative to direction X by angle θ and are periodically repeated.
The third exemplary variation provides diffraction grating 3 D having the third region 3 f located intermediate between the first and second regions 3 a and 3 b and alternately having the first region 3 a structure formed of a protrusion and a depression periodically repeated and the second region 3 b structure formed of a protrusion and a depression periodically repeated. If a direction corresponding to that of guide groove 61 of optical disk 6 is represented as direction Y and a direction perpendicular thereto is represented as direction X, then the third exemplary variation provides diffraction grating 3 D having grating grooves set in a direction inclined relative to directions X and Y by angle θ, similarly as has been described for diffraction grating 3 A with reference to FIG. 3 .
The third exemplary variation provides diffraction grating 3 D having the first and second regions 3 a and 3 b with a boundary therebetween in the form of a comb, and that boundary can be regarded as the third region 3 f . This example is also as effective as or more effective than the first embodiment.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | An optical pickup device has a semiconductor laser emitting light which is in turn branched via a diffraction grating into at least three beams of light including a main beam and two sub beams which are in turn condensed via an objective lens on an optical disk at a guide groove and reflected by the optical disk to provide three reflections of light which are in turn received by detectors, each divided into two regions, respectively, to generate a tracking error signal. The diffraction grating is divided into three regions including a first region, a second region and a third region located intermediate therebetween, each having a periodical structure out of phase, the periodical structure having grating grooves in a direction determined depending on the phase of the second region to incline relative to a direction perpendicular to the guide groove of the optical disk. | 6 |
RELATED APPLICATIONS
[0001] The present application is based on, and claims priority from, United Kingdom Application Number 0506196.5, filed Mar. 29, 2005, the disclosure of which is hereby incorporated by reference herein in its entirety.
FIELD
[0002] The present invention relates to a communication system and method.
BACKGROUND
[0003] Communication systems or computer aided telephony systems are examples of data-processing systems in which a series of automated voice menus prompt a caller or user to press the selective keys on their telephone to achieve a number of purposes. For example the purposes may be to obtain banking services or other financial services, billing queries, assistance or other support services.
[0004] A caller is usually presented with a number of fixed voice menu options presented by a voice application that represents a first layer of options in a tree of voice menu options that, by appropriate selection, will lead the caller to the required assistance or other service automatically, that is, without human intervention. In essence, each layer of voice menu options aims to discover in a progressive manner a caller's intention. Alternatively, the various layers of voice menu options may lead the caller to a human assistant, which has the advantage of providing the human assistant with information relating to the caller's intention or reason for the call in preparation for meeting the caller's needs.
[0005] It will be appreciated that in either circumstance the voice menu options presented are fixed, that is, a standard voice application is created to deal with all queries regardless of any a priori knowledge. It will be appreciated that traversing such a standard voice application can be time-consuming and even frustrating for the caller.
[0006] It is an object of embodiments of the present invention to at least mitigate one or more of the problems of the prior art.
SUMMARY OF INVENTION
[0007] Accordingly, embodiments of the present invention provide a communication system comprising means to process identification data associated with a communication; means, responsive to the identification data, to access a data base to invoke at least one voice application arranged to provide assistance in relation to at least one program; the data base having been configured to comprise the at least one voice application in response to at least one program being executable by the user equipment.
[0008] Advantageously, it will be appreciated that the time taken to address a caller's likely reason for calling can be reduced by attempting to anticipate, in light of prevailing knowledge of, or relating to, programs used by the caller.
[0009] Embodiments provide a communication system in which the data base is configured to comprise the voice application in response to a known problem associated with the application and in which the voice application provides support in relation to that problem. Suitably, prior knowledge of a fault associated with a program used, or accessible, by the caller can reasonably be expected to be behind the caller's motivation for calling. Therefore, configuring or constructing a voice application comprising an entry or entries relating to a known problem or problems of a program or programs respectively might further reduce the time taken for a caller to be directed to appropriate assistance.
[0010] Many support services of companies or other enterprises are available via a telephone number known as, for example, a helpline. Accordingly, embodiments provide a communication system in which the communication is a telephone call. In such circumstances, the identification data comprises at least one of calling line identification data (CLID), dialed number identification service attribute values (DNIS), Calling Number Identification (CNI), AIN equipment or services or any other telephony identification data or identification data associated with the user or equipment accessible to, or used by, the user.
[0011] Other companies or enterprises are known to provide assistance via a communication networks such as, for example, the Internet. Therefore, embodiments provide a communication system in which the communication comprises a data communication having at least one data packet. The at least one data packet may comprise the identification data. It will be appreciated that the identification data might comprise network data such as, for example, an Internet Protocol address or other address that can be associated uniquely with a caller.
[0012] A voice application may comprise a single menu option or a number of menu options. The single menu option, in embodiments of the present invention, can relate to a corresponding fault associated with a program known to be used, or accessible, by the caller. Suitably, embodiments provide a communication system in which the at least one voice application comprises at least a one menu option associated with the at least one program.
[0013] Embodiments can be realised in which a program is known to have a number of associated issues. Accordingly, embodiments provide a communication system in which the at least one voice application comprises a plurality of menu options associated with the program.
[0014] A caller, typically, has access to and uses more than one program. Therefore, embodiments provide a communication system in which the at least one voice application comprises a plurality of menu options; each option being associated with a respective program of a plurality of programs. Each of the menu options can be associated with a fault of a respective program of the program or a selected number of programs accessible to the caller.
[0015] Embodiments can be realised that provide a communication system comprising a plurality of voice applications each comprising a respective menu option; each voice application being associated with a respective program of a plurality of programs.
[0016] It will be appreciated by one skilled in the art that appropriate research would be useful in tailoring the voice applications in anticipation of a caller's requirements. Accordingly, embodiments provide a data processing method comprising creating in, at least one voice application, at least one menu option associated with at least one program accessible by a user; associating user identification data with the voice application to access the voice application in response to receiving the identification data; the user identification data being derived from communication data associated with the user.
[0017] Embodiments provide a data processing method comprising the step of configuring the voice application such that the at least one menu option relates to a known fault associated with the program.
[0018] Embodiments provide a data processing method comprising the step of creating the at least one menu option such that it comprises data relating to instructions to effect a predetermined action to obtain assistance in relation to the known fault.
[0019] Embodiments provide a data processing method in which the step of creating the at least one menu option comprises the step of creating a plurality of menu options such that each menu option of the plurality of menu options relates to a respective known fault of a plurality of faults.
[0020] Embodiments provide a data processing system in which the step of creating, in the at least one voice application, at least one menu option comprises the step of configuring a plurality of voice applications associated with at least one respective fault of a plurality of known fault associated with the at least one program.
[0021] It will be appreciated that embodiments of the present invention can be realised in the form of hardware, software or a combination of hardware and software. Any such software can be stored via a number of mediums such as magnetic or optically readable discs, chips, memory cards, memory sticks or any other volatile or non-volatile medium. Accordingly, embodiments provide a computer program comprising code to implement a system or method described herein. Embodiments also provide computer readable storage storing such a computer program.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which:
[0023] FIG. 1 shows a communication arrangement comprising a communication system according to an embodiment;
[0024] FIG. 2 shows a communication arrangement comprising a computer aided telephony system according to an embodiment;
[0025] FIG. 3 shows flow charts relating to the operation of the embodiments.
DETAILED DESCRIPTION OF EMBODIMENTS
[0026] Referring to FIG. 1 , there is shown a communication arrangement 100 in which a user (not shown) communicates, using communication equipment 102 , with a service platform 104 via a communication network 106 .
[0027] The user equipment 102 allows the user access to a number of applications 108 to 110 stored on, for example, an HDD 112 . The user equipment 102 is illustrated as executing a first application 108 . The user equipment can be, for example, a computer, a telephone, fax machine or any other communication equipment.
[0028] The user of the communication equipment 102 can obtain assistance relating to any or all of the applications 108 to 110 accessible to the user of that equipment 102 . To obtain any such assistance, the communication equipment 102 is used to establish a communication with the service platform 104 . Identification data 114 that uniquely identifies at least one of the user and the communication equipment 102 or, preferably, both, is transmitted to the service platform 104 as part of the communication set up protocol. However, any such identification data 114 could be transmitted to the service platform 104 at some other convenient time.
[0029] The service platform 104 comprises an identifier 116 that extracts the identification data 114 from any communication with the communication equipment 102 . The identifier 116 forwards the identification data 114 , or data derived therefrom, to a match engine 118 that uses the identification data 114 to retrieve, from a user profiles database 120 , the user profile associated with the identification data 114 and, in turn, with the user of the communication equipment 102 . It will be appreciated that the match engine 118 is shown as having retrieved or identified a match between the identification data 114 and a user profile 122 stored within the user profiles database 120 .
[0030] The user profiles database 120 is shown as comprising at least one user profile such as the user profile 122 matching the identification data 114 . It will also be appreciated that a second or further user profile 124 , corresponding to a different user, is also illustrated. The user profiles database 120 may comprise any convenient number of user profiles.
[0031] Each user profile is arranged to contain an indication of the applications accessible by the communication equipment 102 . Taking the first user profile 122 as an example, it can be appreciated that it contains data 126 and 128 respectively identifying the applications 108 to 110 accessible or used by the communication equipment 102 . Therefore, in response to a communication from the user equipment 102 , it is reasonable to assume that any such communication is related to one of the applications 108 to 110 .
[0032] The match engine 118 , in light of the above assumption, also has access to a voice applications database 130 that contains a number of voice applications 132 to 134 . The voice applications database 130 may comprise one voice application or more than one voice application according to requirements even though two voice applications 132 and 134 are illustrated. Each voice application 132 to 134 comprises a number of voice menu options. For example, the first voice application 132 comprises voice menu options 136 to 138 but can comprise any convenient or appropriate number of menu options according to the anticipated needs of a user. Similarly, the other voice application 134 also comprises a number of voice menu options 140 to 142 . Each voice application 132 to 134 has been illustrated as comprising respective pairs of voice menu options. However, each voice application 132 to 134 can comprise any appropriate or convenient number of voice menu options.
[0033] Each voice application 132 to 134 is arranged to correspond to a respective user profile. It can be appreciated that each user profile 122 to 124 comprises an indication 144 to 146 of a respective voice application. The voice application indications 144 to 146 are used by the match engine 118 as an index to retrieve an appropriate voice application from the voice applications database 130 .
[0034] The voice menu options can be expressed in many forms such as, for example, text, for processing by a text-to-speech engine, or digitised speech. The voice application menu options are used to output data as part of an interaction with the user via the communication equipment 102 in an attempt to determine the user's reason for the communication. Each voice menu option is associated with a respective application of the applications 108 to 110 accessible via the communication equipment 102 . Therefore, by tailoring the voice applications 132 to 134 according to the contents of the user profiles 122 to 124 , the user should have a more focused interaction with the service platform 104 , that is, the user will be presented with voice menu options that are potentially more relevant to the user than voice menu options presented by a more generic voice application of, or voice interface to, the service platform 104 .
[0035] An embodiment can be realised in which a voice application is constructed not only in light of the applications 108 to 110 accessible via the communication equipment 102 but also in light of known issues associated with one or more of those applications 108 to 110 . For example, application 108 may have a known fault or bug. Therefore, the first voice application 132 associated with the first user profile 122 corresponding to the user of the communication equipment 102 or the communication equipment 102 itself may comprise a voice menu option relating to that fault or bug. It will be appreciated by one skilled in the art that further tailoring the voice applications in such a manner may lead to the service platform 104 being able to provide the user with assistance or being able to direct the user to assistance in a more focused manner.
[0036] Having identified a voice application such as the first voice application 132 as being relevant to an incoming or established communication, the voice application 132 is forwarded to a communication handler 148 . The communication handler 148 is responsible for managing the exchange or communication between the user of the communication equipment 102 and the voice application. In essence, the communication handler 148 is responsible for executing, or at least overseeing the execution, of the voice application 132 .
[0037] The communication handler 148 comprises a voice menu engine 150 responsible for outputting audible data representing digitised speech according to the voice menu options contained within a voice application currently being processed.
[0038] The communication handler 148 comprises a response processor 152 responsible for processing and identifying the user's responses to the voice menu options. The response processor 152 can be arranged to invoke further voice applications or to direct the user to, for example, an automated assistant 154 or a human assistant 156 via a router 158 according to the responses of the user to the output menu options. The automated assistant 154 may take the form of at least one further voice application or any other form of automated assistance.
[0039] It will be appreciated from FIG. 1 that the voice applications are indicated as being expressed in VoiceXML. However, the voice applications may be expressed or realised in any other suitable form.
[0040] Although the embodiment described above uses the identification data 114 as an index to retrieve a corresponding user profile from the user profiles database 120 , embodiments are not limited to such an arrangement. Embodiments can be realised in which data derived from the identification data 114 is used as such an index. The identification data may be subjected to preprocessing in the form of, for example, a hashing algorithm, to arrive at an index suitable to use with the user profiles database 120 .
[0041] The above communication arrangement 100 has been described using a generic reference to a communication network 106 . Embodiments of such a communication network 106 may take the form of any communication network such as, for example, the Internet, a wired or wireless LAN, or any other type of network supporting communications. The generic reference to communication network 106 also encompasses a cable connection used to couple the communication equipment 102 to the service platform 104 .
[0042] Although the communication arrangement 100 described with reference to FIG. 1 indicates that the communication equipment 102 is responsible for both executing the applications 108 to 110 and supporting the communications with the service platform 104 , arrangements can be realised in which such functions are separated. For example, if the communication equipment 102 is realised in the form of a computer that does not support telephony, the communications with the service platform 104 can be supported using a telephone such as is described below with reference to FIG. 2 .
[0043] The communication arrangement 100 above has been described with reference to the identification data 114 being associated with a user. However, other arrangements can be realised such as, for example, arrangements in which the identification data 114 is associated with the communication equipment 102 rather than with any specific user.
[0044] Referring to FIG. 2 , there is shown a computer aided telephony arrangement 200 that is a telephony based embodiment of the more general communication arrangement 100 shown in and described with reference to FIG. 1 .
[0045] The computer aided telephony arrangement 200 allows a caller (not shown) to communicate, using a telephone 202 , with a computer aided telephony system 204 via a communication network 206 .
[0046] The user has access to a computer 202 ′ that allows the user to access a number of applications 208 to 210 stored on, for example, an HDD 212 . The computer 202 ′ is illustrated as executing a first application 208 . The telephone 202 can be any type of telephone such as, for example, a POTS, a VoIP phone, a wireless telephone or any other type of telephone or communication device.
[0047] The user of the computer 202 ′ can obtain assistance relating to any or all of the applications 208 to 210 accessible to the user of that computer 202 ′. To obtain any such assistance, the telephone 202 is used to establish a call with the computer aided telephony system 204 . It will be appreciated that the term “call” is a species of the class “communication”. Identification data 214 that uniquely identifies at least one of the user or the telephone 202 or, preferably, both, is transmitted to the computer aided telephony system 204 as part of the communication set up protocol. The identification data can comprise Calling Line Identification Data (CLID), Dialed Number Identification Service attribute values (DNIS), Calling Number Identification (CNI), AIN equipment or services or any other telephony identification data or identification data associated with the user or equipment accessible to or used by the user. However, any such identification data 214 could be transmitted to the computer aided telephony system 204 at some other convenient time.
[0048] The computer aided telephony system 204 comprises an identifier 216 that extracts the identification data 214 from any communication exchange with the telephone 202 . The identifier 216 forwards the identification data 214 , or data derived therefrom, to a match engine 218 that uses the identification data 214 to retrieve, from a user profiles database 220 , the user profile associated with the identification data 214 and, in turn, with the user of the telephone 202 . It will be appreciated that the match engine 218 is shown as having retrieved or identified a match between the identification data 214 and a user profile 222 stored within the user profiles database 220 .
[0049] The user profiles database 220 is, for purposes of illustration, shown as comprising at least one user profile such as the user profile 222 matching the identification data 214 . It will also be appreciated that a second or further user profile 224 , corresponding to a different user, is also illustrated. The user profiles database 220 may comprise any convenient number of user profiles.
[0050] Each user profile is arranged to contain an indication of the applications accessible to the user via the computer 202 ′. Taking the first user profile 222 as an example, it can be appreciated that it contains data 226 and 228 respectively identifying the applications 208 to 210 accessible or used by the computer 202 ′. Therefore, in response to a communication from the telephone 202 , it is reasonable to assume that any such communication is related to one of the applications 208 to 210 .
[0051] The match engine 218 , in light of the above assumption, also has access to a voice applications database 230 that contains a number of voice applications 232 to 234 . The voice applications database 230 may comprise one voice application or more than one voice application according to requirements even though only two voice applications 232 and 234 are illustrated. Each voice application 232 to 234 comprises a number of voice menu options. For example, the first voice application 232 comprises voice menu options 236 to 238 but can comprise any convenient or appropriate number of menu options according to the anticipated needs of a user. Similarly, the other voice application 234 also comprises a number of voice menu options 240 to 242 . Each voice application 232 to 234 has been illustrated as comprising respective pairs of voice menu options. However, each voice application 232 to 234 can comprise any appropriate or convenient number of voice menu options.
[0052] Each voice application 232 to 234 is arranged to correspond to a respective user profile. It can be appreciated that each user profile 222 to 224 comprises an indication 244 to 246 of a respective voice application. The voice application indications 244 to 246 are used by the match engine 218 as an index to retrieve an appropriate voice application from the voice applications database 230 .
[0053] The voice menu options can be expressed in many forms such as, for example, text, for processing by a text-to-speech engine, or digitised speech. The voice application menu options are used to output data as part of an interaction with the user via the telephone 202 in an attempt to determine the user's purpose in making the call. Each voice menu option is associated with a respective application of the applications 208 to 210 . Therefore, by tailoring the voice applications 232 to 234 according to the contents of the user profiles 222 to 224 , the user should have a more focused interaction with the computer aided telephony system 204 , that is, the user will be presented with voice menu options that are potentially more relevant to the user than voice menu options presented by a more generic voice application of, or voice interface to, the computer aided telephony system 204 .
[0054] An embodiment can be realised in which a voice application is configured or constructed not only in light of the applications 208 to 210 accessible via the computer 202 ′ but also in light of known issues associated with one or more of those applications 208 to 210 . For example, application 208 may have a known fault or bug. Therefore, the first voice application 232 associated with the first user profile 222 corresponding to the caller may comprise a voice menu option relating to that fault or bug. It will be appreciated by one skilled in the art that further tailoring the voice applications in such a manner may lead to the computer aided telephony system 204 being able to provide the user with assistance or being able to direct the user to assistance in a more focused manner.
[0055] Having identified a voice application such as the first voice application 232 as being relevant to an incoming or established call, the voice application 232 is forwarded to a communication handler 248 . The communication handler 248 is responsible for managing the exchange or communication between the user of the telephone 202 and the voice application. In essence, the communication handler 248 is responsible for executing, or at least overseeing the execution, of the voice application 232 .
[0056] The communication handler 248 comprises a voice menu engine 250 responsible for outputting audible data representing digitised speech according to the voice menu options contained within a voice application currently being processed. The voice menu engine 250 achieves this by extracting, for example, text, assuming the voice menu options are expressed using text, from the menu options and forwarding the text to a text-to-speech engine 250 ′ for conversion of the text to speech data.
[0057] The communication handler 248 comprises a response processor 252 responsible for processing and identifying the user's responses to the voice menu options. The response processor 252 uses an automatic speech recogniser (ASR) 252 ′ to process data representing the responses of the user to the voice menu options. The data representing the responses can take the form of DTMF tones or other signals generated using the telephone or caller articulations that are processed by the ASR. The ASR outputs data reflecting the caller's responses to the menu options to the response processor. The response processor 252 can be arranged to invoke further a voice application or to direct the user to, for example, an automated assistant 254 or a human assistant 256 via a router 258 according to the responses of the user to the output menu options. The automated assistant 254 may take the form of at least one further voice application or any other form of automated assistance.
[0058] It will be appreciated from FIG. 2 that the voice applications are indicated as being expressed in VoiceXML, in which case the voice menu engine 250 may be a VoiceXML interpreter. However, the voice applications may be expressed or realised in any other suitable form.
[0059] Although the embodiment described above uses the identification data 214 as an index to retrieve a corresponding user profile from the user profiles database 220 , embodiments are not limited to such an arrangement. Embodiments can be realised in which data derived from the identification data 214 is used as an index. For example, the identification data may be subjected to preprocessing in the form of, for example, a hashing algorithm, to arrive at an index suitable for use with the user profiles database 220 .
[0060] The above computer aided telephony arrangement 200 has been described using a generic reference to a communication network 206 . Embodiments of such a communication network 206 may take the form of any communication network such as, for example, the Internet, a wired or wireless LAN, a PSTN or mobile communication network or any other type of network supporting telephony communications. The generic reference to communication network 206 also encompasses a cable used to couple the telephone 202 to the computer aided telephony system 204 .
[0061] The computer aided telephony arrangement 200 above has been described with reference to the identification data 214 being associated with the telephone. However, other arrangements can be realised such as, for example, arrangements in which the identification data 214 is associated with the computer 202 ′ or a communication protocol associated with the telephone 202 or computer 202 ′, network or application rather than with the telephone specifically. For example, identification data relating to the computer 202 ′ such as, for example, an IP address might be used. However, such an embodiment would require the computer aided telephony system 204 to correlate the telephone call with a communication established, or to be established, with the computer 202 ′.
[0062] Referring to FIG. 3 there is shown a pair of flow charts 300 depicting the processing undertaken by the above embodiments. A first flow chart 302 of the pair of flow charts 300 relates to processing activities undertaken by equipment such as the telephone 202 , computer 202 ′ or communication equipment 102 used by a user or a caller. A second flow chart 304 illustrates the processing undertaken by the service platform 104 or computer aided telephony system 204 . The flow charts will be described with reference to FIG. 2 . However, the flow charts 300 are equally applicable to the communication arrangement shown in and described with reference to FIG. 1 .
[0063] At step 306 , the caller establishes or at least instigates a call to the computer aided telephony system 204 . Step 306 also includes forwarding identification data such as, for example, the CLID, DNIS attribute values, CNI or AIN data. The call set up data, including the identification data, is received at the computer aided telephony system 204 at step 308 . The identification data is extracted or identified at step 310 and forwarded to the match engine 218 . A search is performed at step 312 to determine whether or not the user profiles database 220 contains a user profile matching the extracted identification data. A determination is made at step 314 as to whether or not such a match exists. If it is determined that such a match does not exist, processing continues at step 316 where the caller is invited to take part in a registration process to collate data from which an appropriate user profile can be constructed. If the determination at step 314 is that a user profile corresponding to the extracted identification data does exist, the voice XML indication contained within the appropriate user profile is retrieved or identified at step 318 and used, at step 320 , to retrieve a voice application corresponding to the user profile. The voice application is executed at step 322 which invariably involves an exchange or interaction with the caller as indicated by the process shown at step 324 .
[0064] Returning to the registration process undertaken at step 316 , the details relating to the applications 208 to 210 used or accessible by the user are collated. Any such collation can be achieved in a number of ways. For example, the caller could be directed to a web page that has an embedded executable entity, such as an applet or the like, responsible for identifying the applications 208 to 210 used by or accessible to the computer 202 ′. As a refinement, the user can be presented with the list of applications identified by the executable entity and requested to select from such a list those applications to be registered with the computer aided telephony system 204 as being of interest.
[0065] Although the above embodiments make reference to applications, it will be appreciated that they are not limited to constructing a user profiles database relating to applications. Also, applications are merely species of the more generic class “programs”. Also, it will be appreciated that the service platform 104 and the computer aided telephony system 204 are realisations of a communication system or at least part of such a system.
[0066] The user profiles databases 120 and 220 and the voice applications databases 130 and 230 have been shown as separate databases. However, embodiments can be realised in which the databases are combined. For example, each user profile within the user profiles databases 120 and 230 could be arranged to contain the voice applications themselves rather than merely indexes that are used to access such voice applications.
[0067] Embodiments can be realised in which a menu option can be presented to a caller or user to allow them to run the registration process described with reference to step 316 to update the programs registered with the service platform 104 or computer aided telephony system 204 as being associated with the caller or user. | Embodiments of the present invention relate to a communication system comprising means to process identification data associated with a communication; and means, responsive to the identification data, to access a data base to invoke/execute at least one voice application arranged to provide assistance in relation to at least one program; the data base having been configured to comprise the at least one voice application in response to the at least one program being executable by the user equipment. | 7 |
BACKGROUND
The present disclosure generally relates to electromachining apparatuses and processes, and more particularly, to an electromachining apparatus and process configured for providing both roughing and finishing operations.
A large amount of time is spent in machining different types of metal components for commercial and industrial usage. The amount of time is generally dependent on the material being machined and the machining method used. One method used frequently for complex components, particularly those with contours, is milling. This can take a substantial amount of the overall component processing time. For the most demanding applications, carbide cutters are typically utilized. Other methods include electrodischarge machining (EDM) which is widely used for machining complex parts and dies and molds.
EDM is a process in which an electrically conductive metal workpiece is shaped by removing material through melting or vaporization by electrical sparks and arcs. The spark discharge and transient arc are produced by applying controlled pulsed direct current between the workpiece (typically anodic or positively charged) and the tool or electrode (typically the cathode or negatively charged). The end of the electrode and the workpiece are separated by a spark gap generally from about 0.01 millimeters to about 0.50 millimeters, and are immersed in or flooded by a dielectric fluid. The DC voltage enables a spark discharge charge or transient arc to pass between the tool and the workpiece. Each spark and/or arc produces enough heat to melt or vaporize a small quantity of the workpiece, thereby leaving a tiny pit or crater in the work surface. The cutting pattern of the electrode is usually computer numerically controlled (CNC) whereby servomotors control the relative positions of the electrode and workpiece. The servomotors are controlled using relatively complex and often proprietary control algorithms to control the spark discharge and control gap between the tool & workpiece. By immersing the electrode and the workpiece in the dielectric fluid, a plasma channel can be established between the tool and workpiece to initiate the spark discharge. The dielectric fluid also keeps the machined area cooled and the removes the machining debris. An EDM apparatus typically includes one or more electrodes for conducting electrical discharges between the apparatus and the part.
One drawback to current EDM processes is that it is a relatively slow process, especially when several distinct features need to be machined into a workpiece. This is particularly so in the aircraft engine industry where electrical discharge machining is widely used for machining various features into aircraft engine parts. Because of this as well as for other reasons, EDM is generally used for fine finishing and not for roughing operations where large quantities of material are removed.
High-speed electroerosion processes have been recently developed that uses spark/arc discharges through an electrolytic medium. Although these processes utilize an electrolyte, it is typically much weaker than those electrolytes used in an electrochemical machining (ECM) processes, and the primary material removal mechanism is thermal via spark/arc discharge. The high speed electroerosion process must have relative movement between the tool and workpiece, and this process uses a different control method relative to EDM.
It would be desirable to have an electromachining apparatus and process that efficiently provides both high speed roughing using the high speed electroerosion process and finishing of the workpiece by EDM.
BRIEF SUMMARY
Disclosed herein is an electromachining apparatus and process. In one embodiment, the electromachining apparatus comprises an electrode spindle system comprising a removable electrode spaced apart from a workpiece; a DC power source in electrical communication with the electrode spindle system; and an electrolyte fluid source and a dielectric fluid source in fluid communication with the electrode, wherein the fluid communication to the electrode is of a selected one of the electrolyte fluid and the dielectric fluid is controlled by a valve.
A process for roughing and finishing a workpiece comprises rotating a rotatable electrode spaced apart from a workpiece to define a gap therebetween and flowing an electrolyte fluid into the gap; supplying DC power to the rotatable electrode in an amount effective to roughly electrochemically erode portions of the workpiece; stopping the rotating electrode and the flow of the electrolyte; mounting a non-rotating electrode and flowing a dielectric fluid into the gap and supplying DC power to the non-rotating electrode in an amount effective to finely electroerode portions of the workpiece.
A process for roughing and finishing a workpiece comprises rotating a rotatable electrode spaced apart from a workpiece to define a gap therebetween and flowing an electrolyte fluid into the gap; supplying DC power to the rotatable electrode in an amount effective to roughly electrochemically erode portions of the workpiece; stopping the rotating electrode and the flow of the electrolyte; mounting a non-rotating electrode and flowing a dielectric fluid into the gap and supplying DC power to the non-rotating electrode in an amount effective to finely electroerode portions of the workpiece.
In another embodiment, the process for roughing and finishing a workpiece comprises rotating a first electrode spaced apart from a workpiece to define a first gap therebetween and flowing an electrolyte fluid into the gap; supplying DC power to the first electrode in an amount effective to roughly electrochemically erode portions of the workpiece; stopping the rotating electrode and the flow of the electrolyte; mounting a second electrode spaced apart from the workpiece to define a second gap and flowing a dielectric fluid into the second gap; and pulsing the DC power to the second electrode in an amount effective to finely electroerode portions of the workpiece.
The disclosure may be understood more readily by reference to the following detailed description of the various features of the disclosure and the examples included therein.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the figures wherein the like elements are numbered alike:
FIG. 1 illustrates a hybrid electromachine for roughing and finishing a part in accordance with an embodiment of the disclosure; and
FIG. 2 illustrates an electrode suitable for the electromachining apparatus in accordance with another embodiment.
DETAILED DESCRIPTION
Disclosed herein are electromachining apparatuses and processes that permit rapid prototyping of a workpiece. The apparatuses and processes provide both roughing and finishing operations with the same tool set, thereby providing a significant commercial advantage. Generally, the electromachining apparatus combines both high-speed electroerosion functions and electrodischarge machining (EDM) functions to provide the roughing and finishing operations. During the initial roughing operation, a rotary electrode removably attached to a spindle is rotated and moved about the workpiece. A gap within the electrode allows for the flow of electrolyte. Electrical erosion to the workpiece to provide a near net shape is created by electrical breakdown of the electrolyte and a vapor gas layer produced at the interface between the electrode and the workpiece where material is being removed as well as by instantaneous short circuits or transient arcs between the electrode and the workpiece.
To provide finishing of the roughed workpiece, the apparatus is configured to function in a manner similar to an electrodischarge machine. The rotary electroerosion type electrode used in the high speed electroerosion process is removed and an EDM electrode is attached to the spindle and utilized such that a current flows between the electrode and the part to be finished, i.e., workpiece. In one embodiment, the spindle (and electrode) during the finishing operation would not be rotating and the flow of electrolyte is replaced with a flow of a dielectric fluid. The resulting spark erosion within the dielectric medium provides finishing.
Since non-mechanical means are used to remove and shape the material, low cost tools made of soft metals or any electrically conductive material can be used to significantly lower tooling costs. The workpiece metal removal rate can be increased by intense electrothermal actions, and no significant “cutting forces” are generated so that simple, low rigidity machines can be used that greatly reduce cost. Further, no compensation is necessary for tooling deflection that is common in mechanical milling. As a non-mechanical process, the electro-machining speed is independent of workpiece material hardness and toughness. Higher metal removal speed than milling for tough workpiece metals can be achieved through high intensity electrothermal reactions.
In one embodiment, a multi-axis machine with numerical control on each axis, is used to drive the different electrodes and workpiece movements for machining the workpiece. The electrodes are made of an electrically conductive metal such as brass or other low cost metals. Suitable materials for fabricating the electrode include, but are not limited to, graphite, tungsten copper, tellurium copper, tungsten carbide, brass, pure tungsten, copper, copper alloys, and combinations comprising at least one of the foregoing. The electrode rotates during the high speed electroerosion and is non-rotating during EDM. The electrodes may be any shape (e.g. cylindrical, conical) and size depending on the application. DC power (continuous or pulsed) is used to provide voltage across the tool and workpiece. For the EDM finishing operation, the DC voltage is pulsed. Workpiece metal is roughly and finely removed in a controlled manner by high intensity electro thermal erosion provided by the apparatus.
The control system can regulate tool feed speed and/or pulse intervals to ensure high efficient erosion. Depending on the sensed conditions, tool feed speed can be increased if erosion intensity (as measured by erosion current) is not up to a set level, or it can be maintained at a constant speed when the erosion intensity reaches the set level. Alternatively, the tool feed speed can be reduced if persistent arcing or short-circuiting is detected. Likewise, the control system can provide a suitable voltage required for the particular operation, e.g., the electroerosion roughing with an electrolyte fluid or EDM finishing with a dielectric fluid. The fluids are continuously filtered and can be recycled during use. The apparatus may further include a heat exchanger for removing heat from the fluids during operation.
FIG. 1 shows a schematic representation of an exemplary electromachining apparatus generally designated by reference numeral 10 . The electromachining apparatus 10 is depicted as being supported on a robotic type multi-joint motorized arm 12 . The motorized arm 12 is configured to move an electrode spindle system 14 , which is driven to rotate by a motor unit 16 , in a least three mutually opposed directions. The electrode spindle system 14 is selectively supplied an electrolyte fluid or a dielectric fluid from source 18 , 20 , respectively via a nozzle 20 . The fluid source 18 , 20 can include a pump or the like for inducing a flow of fluid. Alternatively, an electrode 38 of the electrode spindle system can have a hollow tubular profile in which the fluid is passed therethrough. In another embodiment, the electrode may be manipulated by any multi-axis system such as that which may be used in conventional milling practice. In another embodiment, the workpiece is immersed in the fluid by use of a container (not shown). Optionally, the container further includes a flushing and filtering system. Suitable flushing and filtering systems are disclosed in U.S. patent application Ser. No. 10/708,879 filed on Mar. 20, 2004, incorporated herein by reference in its entirety. Selection of the particular fluid is controlled by valve 24 . The fluid sources 18 , 20 can be external to the electromachine apparatus as shown or integrated within the machine itself.
The motorized arm 12 is supported on a base 26 which can include a CNC (computerized numerical controller) device 28 , which is operatively connected with the motors of the motorized arm 12 , and a DC power source 30 , which is operatively connected with the electrode spindle system 14 . The DC power source can be adapted to provide a continuous voltage or pulsed voltage across the electrode spindle system 14 and a workpiece 32 (The workpiece 32 is not itself a part of the electromachining apparatus 10 , but is operable with the workpiece 32 .).
The CNC device 28 can be programmed to manipulate the electrode spindle system 14 in a manner which enables the work piece 32 to be shaped via erosion and so that complex shapes such as those of airfoil blades or the like can be quickly and economically produced. Also, the CNC device 28 provides a means to regulate tool feed speed based on the detection of erosion process to avoid persistent arcing or short-circuiting. In this figure, the work piece 32 is schematically depicted as being an airfoil and is shown clamped with clamp members 34 in a position adjacent the base 26 .
The electrode 38 is preferably made of electrically conductive material such as graphite and has a shape, which generally mirrors the desired machined shape. The electrode can have a solid or a hollow profile. With the solid profile, the electrolyte or dielectric fluid flow from the nozzle 22 . For a hollow profile, the electrolyte or dielectric fluid flow can flow internally through the electrode. Other suitable electrode materials include copper, tungsten copper, tellurium copper, tungsten carbide, brass, pure tungsten, and the like. Selection of the particular ECDM and EDM electrodes as well as the operating parameters will generally depend on the workpiece being machined, which is well within those skilled in the art.
The apparatus may also include a graphical or other display, such as CRT graphical display (not shown) to monitor signals provided by any of the components of the apparatus previously described. Such a graphical or other display may provide diagnostic information to a machine operator to ascertain that each electrode is performing properly, or to fulfill some other diagnostic purpose.
FIG. 2 illustrates a cross sectional view of a hollow electrode 40 . The electrode 40 includes a hollow interior region through which the fluid flows.
During the electroerosion roughing operation, the electrode 38 is in rotative motion relative to the workpiece and is in motion thereabout in order to avoid dwells and excessive arcing. Electrolyte is provided at the gap between the electrode and the workpiece. The electrolyte fluid can be water or an aqueous electrolyte solution, dispersion, or mixture of suitable electrolytic substances/liquids or the like that provides a conductive medium through which an electrical arc can pass. Merely by way of example, solutions of NaNO 2 , NaOH, NaNO 3 , Na 2 CO 3 , NaCl and mixtures thereof can be used. In one embodiment, the electrolyte is selected to have an electro-conductivity value of 20 microsiemens/cm to 100 millisiemens/cm, wherein the electro-conductivity can be adjusted by salt addition. Optionally, the electrolyte can include other additives, e.g., an anti-rust additive.
During the (EDM) finishing operation, a non-rotating EDM electrode of a suitable shape replaces the electroerosion electrode and the flow of electrolyte is replaced with a flow of the dielectric fluid. The dielectric fluid is a liquid dielectric or mixture of different dielectric fluids. The dielectric fluid is selected to insulate and cool the electrode and workpiece, convey the spark, and flush away the removed metal. Suitable dielectric fluids are non-conductive and include hydrocarbon oils, deionized water, polyolefins, esters, and the like. The rate of advance towards workpiece 32 (in the direction of the arrow 36 ), termed the electrode feedrate, may be regulated to maintain a predetermined standoff distance between the electrode and the workpiece so that when the electrode is energized with the DC power a plurality of electrical discharges between the electrode and the workpiece performs the machining, i.e., results in spark erosion. Optionally, depending on the part size and desired finish features, either a rotary tool could be used or most likely, a shaped tool that does not rotate would generate the finish machined surfaces.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims. | An electromachining process and apparatus includes providing both high-speed electroerosion functions for rapidly rough finishing a workpiece and electrodischarge machining functions for fine finishing by first using a rotary electrode to implement the high-speed electroerosion function, and then removing and replacing the rotary electrode with an EDM electrode to implement the electrodischarge machining functions. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
Embodiments of the present invention generally relate to methods of cleaning scale and deposits and altering the surface and shape of the inside diameter of tubulars within an oil and gas wellbore.
2. Description of the Related Art
Hydrocarbon wells typically, begin by drilling a borehole from the earth's surface to a selected depth in order to intersect a formation. Steel casing lines the borehole formed in the earth during the drilling process. This creates an annular area between the casing and the borehole that is filled with cement to further support and form the wellbore. Thereafter, the borehole is drilled to a greater depth using a smaller diameter drill than the diameter of the surface casing. A liner may be suspended adjacent the lower end of the previously suspended and cemented casing. Production operations often require lining the borehole with a filtration medium. Examples of common filtration media include slotted pipe or tube, slotted screens or membranes, and sand-filled screens. In general, the diameter, location, and function of the tubular that is placed in the well bore determines whether it is known as casing, liner, or tubing. However, the general term tubular or tubing encompasses all of the applications.
After completing various operations during the completion of the wellbore, ledges and debris are often left on the inside diameter of the tubular. Excess cement sometimes hardens on the inside of the tubulars after cementing of the liner or casing in the wellbore. Certain downhole milling operations leave metal pieces on the inside of tubulars from either equipment remnants or burrs on the tubular itself. For example, drilling out a packer in order to remove it from the tubular may not fully eliminate all of the metal that comprised the packer. Also, milling a window in the casing to run a horizontal bore causes metal burrs on the inside of the casing around the window.
Well tubulars often become plugged or coated during production from corrosion products, sediments, and hydrocarbon deposits such as paraffin. At elevated temperatures underground paraffin is a liquid and flows easily; however, the petroleum and paraffin cools off as the petroleum travels up the well bore toward the surface. At some point the temperature drops low enough to allow the paraffin to solidify on the tubulars in the well bore. Paraffin deposits primarily present a problem for sub-sea tubulars. Other scum and deposits on the inside of tubulars consist of silicates, sulphates, sulphides, carbonates, calcium, and organic growth. Soft deposits such as clay and sand from the formations can enter the bore at locations where the casing or liner has been perforated for production. Highly deviated and horizontal bores are particularly susceptible to collecting debris.
Debris that collects on the inside surface of the tubular that defines the bore can obstruct passage through the bore of tubing, equipment, and tools used in various exploration and production operations. Even if the tool can pass through the bore, debris often causes wear and damage to the tubing, equipment, and tools that pass through it. Sustaining production rates requires periodic cleaning since deposits and solidified paraffin on the inside of production tubulars slows down production of oil from the well.
Pressure changes in the wellbore, swelling of surrounding formations, earth movements, and formation changes deform downhole tubulars. Therefore, a cross section of downhole tubulars becomes more irregular and non-round over time. Exposure to erosion and corrosion add to the roughness and inconsistent roundness of the inside surface of the tubulars. Even initially, the inside surface of a tubular is typically rough and inconsistently round. Many tools used in downhole operations require a smooth round surface in order to properly operate or make a sealing engagement with the tubular. In addition, a polished bore receptacle that allows for a non-leaking engagement between two tubulars requires a smooth, clean, and substantially round surface. Placing a seal within a polished bore receptacle insures a fluid tight seal between the tool or tubular seated within the polished bore receptacle.
In order to create a polished bore receptacle, the roughness of the tubular's inside diameter must be smoothed, and the inside diameter of the tubular must be reformed into a more uniformly round surface. Since burnishing alters a tubular's surface characteristics, burnishing the inside diameter of the tubular can establish a polished bore receptacle. Therefore, the burnished inside diameter creates a smooth and substantially round surface.
Current operations to clean the inside of tubulars include circulating treating and cleanout fluids such as water, oil, acid, corrosion inhibitors, hot oil, nitrogen, and foam in the tubular. However, physical dislodging of the debris on the tubular walls is sometimes required. Fixed diameter reaming members, scrappers, shoes on the end of tubulars, and circulating cleanout fluids do not allow the ability to clean, alter the surface finish, and/or round various sizes of tubulars during one downhole operation.
Therefore, there exists a need for an improved method of physically removing debris from the inside diameter of a wellbore tubular. There exists a further need for an improved method of burnishing the inside diameter of a wellbore tubular, thereby altering and rounding its surface characteristics.
SUMMARY OF THE INVENTION
The present invention generally relates to a method for cleaning and/or altering an inside surface finish and shape of a tubular in a wellbore. The method includes placing a surface finishing tool in the tubular, energizing the tool, and causing extendable assemblies therein to extend radially into contact with an inside diameter of the tubular. Moving the tool axially and/or rotationally while a portion of the extendable assembly is in contact with the inside diameter of the tubular cleans out debris that has collected in the tubular. In another aspect of the invention, the tool burnishes the inside diameter of the tubular, thereby altering the surface characteristics and rounding the tubular.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1 is an exploded view of an embodiment of the surface finishing tool used for cleaning, resurfacing, and/or rounding wellbore tubulars.
FIG. 1A is a section view across line 1 A— 1 A of FIG. 1 .
FIG. 2 is an exploded view of an alternative embodiment of the surface finishing tool.
FIG. 3 is a longitudinal section view of an embodiment of the surface finishing tool as it would appear in a well bore prior to actuating the extendable assemblies.
FIG. 4 is a view of the embodiment in FIG. 3 after actuating the extendable assemblies inside the tubular and moving the tool within the tubular.
FIG. 5 is a longitudinal section view of an embodiment of the surface finishing tool as it would appear within casing having a window formed in a wall thereof.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows an exploded view of the surface finishing tool 100 with a body 102 that is hollow and generally tubular. FIG. 1A presents the same surface finishing tool 100 in cross-section, with the view taken across line 1 A— 1 A of FIG. 1 . The central body 102 has a plurality of recesses 114 to hold a respective extendable assembly 110 . Each of the recesses 114 has substantially parallel sides and holds a respective piston 120 . The pistons 120 are radially slidable, one piston 120 being slidably sealed within each recess 114 . The backside of each piston 120 is exposed to the pressure of fluid within a hollow bore 115 of the surface finishing tool 100 . In this manner, pressurized fluid provided from the surface of the well can actuate the pistons 120 and cause them to extend outwardly.
Disposed above each piston 120 is a roller 116 . In one embodiment of the surface finishing tool 100 , the rollers 116 are near cylindrical and slightly barreled. Each of the rollers 116 is supported by a shaft 118 at each end of the respective roller 116 for rotation about a respective axis. The rollers 116 are generally parallel to the longitudinal axis of the tool 100 . In the arrangement of FIG. 1, the plurality of rollers 116 is radially offset at mutual 120-degree circumferential separations around the central body 102 . In the arrangement shown in FIG. 1, two offset rows of rollers 116 are shown. However, only one row, or more than two rows of roller 116 , may be incorporated into the body 102 . An abrasive surface may be added to the outer circumference of the rollers 116 .
FIG. 2 illustrates an alternative embodiment of the extendable assembly 110 of the surface finishing tool 100 . Solid independent non-rolling members 200 disposed above each piston 120 replaced the rollers 116 from FIG. 1. A portion of the non-rolling member 200 opposite the piston 120 possesses a plurality of edges that form teeth. Similarly, the ends of the non-rolling members 200 that extend from the tool 100 may be hard bristles that form a brush, sharpened edges, or blades. The non-rolling member 200 can replace one or more of the rollers 116 from the embodiment shown in FIG. 1 . For example, a leading offset row of extendable assemblies 110 may comprise non-rolling members 200 with brush ends while a tailing offset row of extendable assemblies 110 includes the rollers 116 shown in FIG. 1 .
FIG. 3 illustrates an embodiment of the present invention as it would appear positioned inside a casing 300 within a wellbore 302 . In this embodiment, a plurality of non-compliant rollers 312 positioned parallel to the longitudinal axis of the tool 100 and on a portion of the tool with a gradually increasing outer diameter prevent the tool from jamming in areas of the tubulars that have a constricted inside diameter. Common known methods of lowering the surface finishing tool 100 into the wellbore include attaching the tool to a tubing string 304 or coiled tubing (not shown). If coiled tubing is utilized, a mud motor (not shown) disposed on the coiled tubing provides rotational force to the surface finishing tool 100 . Both a mud motor's structure and its function are well known in the industry. In FIG. 3, the surface finishing tool 100 is illustrated in a section of casing 300 adjacent to debris 308 that is to be cleaned from the casing's inside surface and the deformation 310 that is to be rounded. While FIG. 3 illustrates the surface finishing tool positioned in casing 300 , the surface finishing tool can be utilized in any downhole tubular such as liners or production tubulars.
FIG. 4 shows the device in FIG. 3 after the surface finishing tool 100 has been actuated and moved relative to the tubular 300 . After the surface finishing tool is in place and at a predetermined time, fluid pressure applied through the tubing string 304 and into the surface finishing tool 100 extends the extendable assembly 110 radially outward into contact with the inside diameter of the tubular 300 . At least one aperture 400 at the lower end of the tool 100 permits fluid to pass through the tool and circulate back to the surface. Rotating the surface finishing tool 100 in the tubular and/or moving the surface finishing tool 100 axially in the tubular while a portion of the extendable assemblies 110 contact the inside diameter of the tubular 300 physically dislodges debris 308 from the inside surface of the tubular 300 . While FIG. 4 shows extendable assemblies 110 with rollers 116 contacting the inside diameter of the tubular, extendable assemblies 110 with the solid independent non-rolling members described herein can be utilized to clean debris 308 from the tubular 300 . The type of debris 308 to be cleaned from the inside surface determines whether the roller 116 or one of the non-rolling members that utilize brushes, teeth, or edges will provide the most efficient cleaning. Outward radial force applied by the surface finishing tool 100 reshapes the inside circumference of the tubular 300 into a more uniformly round shape as the tool rotates inside the irregular section 310 (shown in FIG. 3 ). Axial and rotational movement of the tubing string 304 from the surface moves the surface finishing tool 100 respectively within the tubular.
A surface finishing tool with the same features as described in FIG. 1 or FIG. 2 can be used to burnish the inside diameter of a tubular in order to prepare a polished bore receptacle. The term burnish refers broadly to any changes in the surface characteristics of the tubular's inside diameter. Continued rotation of the tool 100 while the rollers 116 contact the inside diameter of the tubular 300 burnishes a section of the inside diameter of the tubular. Prior to burnishing, the surface finishing tool 100 has cleaned the inside surface of the tubular and reformed the inside surface into a more rounded shape. Burnishing and rounding the inside surface of the tubular 300 with the finishing tool 100 after removing debris 308 with other known apparatuses utilizes the finishing tool in conjunction with other known cleaning devices. The smoothed, cleaned, polished, and substantially rounded inside surface of the tubular as shown in FIG. 4 . provides the required surface and finish needed for a polished bore receptacle. Therefore, a second tubular or tool can be seated within the polished bore receptacle to provide a fluid tight seal.
FIG. 5 illustrates the surface finishing tool 100 inside a casing 300 that a window 500 has been milled through a wall thereof. The milling process left metal burrs 502 circumscribing the window 500 . Fluid pressure applied to the surface finishing tool 100 extends the extendable assembly 110 until the rollers 116 contact the inside diameter of the casing 300 . Therefore, moving the actuated surface finishing tool 100 across the window 500 removes the metal burrs 502 . As the surface finishing tool moves axially through the casing 300 the irregularity 310 is formed into a more rounded inside surface and debris 308 is removed. Therefore, the altered inside surface of the casing 300 permits substantially unobstructed fluid flow through the casing and allows passage of subsequent downhole tools without the risk of damage or becoming stuck since the burr 502 , the irregular shape 310 , and the debris 308 have all been removed or reformed. During one downhole operation with the finishing tool 100 , tubulars with multiple sizes of inside diameters can be refinished since the tool's diameter varies with the extension of the extendable assemblies 110 .
While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. | A method for cleaning and/or altering an inside surface and shape of a tubular in a wellbore. The method includes placing a surface finishing tool in the tubular, energizing the surface finishing tool, and causing extendable assemblies therein to extend radially to contact an inside diameter of the tubular. Moving the surface finishing tool axially and/or rotationally while the extended members are in contact with the inside diameter of the tubular cleans debris from the inside surface of the tubular. In another aspect of the invention, the tool burnishes the inside diameter of the tubular, thereby altering the surface characteristics and rounding the tubular. | 4 |
[0001] This application is a continuation of application Ser. No. 10/064,870 filed on Aug. 26, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a beverage container holder. In one aspect, the invention relates to a beverage container holder that is size-adjustable to accommodate varying sizes of beverage containers. In another aspect, the invention relates to a beverage container holder that thermally conditions the air surrounding the beverage container to control the temperature of the beverage within the beverage container.
[0004] 2. Description of the Related Art
[0005] Most contemporary vehicles (cars, trucks, boats, etc.) are usually accessorized with a cup holder. Such cup holders are sized to receive cups or beverage containers for both hot and cold beverages. Some cup holders are size-adjustable to accommodate cups of varying diameters while still snugly retaining the cup and thereby preventing the tipping or spilling of the cup during the normal operation of the vehicle.
[0006] It is becoming more difficult for a single cup holder to accommodate all of the various standard cup sizes, especially since the largest cup sizes for cold beverages is generally 44 ounces and larger, while the largest cup size for hot beverages is generally 20 ounces or less. The problem of accommodating all cup sizes is exacerbated by what appears to be an ever increasing largest cup size for cold beverages.
[0007] Current cup holders are also not configured to accommodate bottles and other beverage containers that have generally straight side walls, unlike the tapered side walls found on most cups. With the recent increase in the popularity of water and sports drinks that come in straight-walled bottles, it is now important for a cup holder to accommodate the generally taller and straight sidewall shape of bottles in addition to accommodating the traditional tapered cup.
[0008] One feature almost all cup holders currently lack is the ability to control the temperature of the beverage in the beverage container, regardless whether the container is a cup or a bottle and whether the beverage is a hot or cold beverage. The need to control the temperature of the beverage becomes more important as people spend greater amounts of time in their vehicles, especially cars and trucks.
[0009] There is a need for a cup holder that addresses all of the disadvantages found in contemporary cup holders. The cup holder should accommodate beverage containers of all shapes and sizes, both in height and circumference, and control the temperature of the beverage.
SUMMARY OF THE INVENTION
[0010] The invention addresses the shortcomings of prior art cup holders and relates to a thermal conditioning beverage container holder for holding all types of beverage containers while controlling the temperature of the beverage in the beverage container. The beverage container holder according to the invention comprises a housing defining a chamber sized to receive a beverage container and having an access opening permitting access to the chamber through the housing. A convection airflow generator is fluidly coupled to the chamber and delivers thermally conditioned air to the chamber to control the temperature of the beverage within a beverage container placed in the chamber. The beverage container holder includes a size-adjustable structure to enable the supporting of cups of differing sizes.
[0011] The thermal conditioning beverage container holder can further include a movable cover for selectively closing the access opening. The movable cover preferably comprises multiple segments that telescopically nest when opened.
[0012] The size adjustable structure can comprise a resizing element used to resize the container holder to accommodate containers of differing diameter and/or height. One such resizing element is a beverage container support located within the chamber and sized to support a bottom portion of the beverage container, with a first recess for receiving the bottom of the beverage container up to a first maximum diameter. A second recess, greater in size than the first recess, can be provided for receiving the bottom of a beverage container of a second maximum diameter that is larger in size than the first maximum diameter.
[0013] The resizing element can also comprise a plate in which is formed an opening for receiving a beverage container and which is movable between a first position, where the plate overlies the chamber to reduce the effective cross-sectional area of the chamber, and a second position, where the plate is withdrawn from the overlying position relative to the chamber. The plate is preferably spaced above the beverage container support when the plate is in the first position.
[0014] The convection airflow generator comprises a thermal conditioner for conditioning the temperature of the air in the chamber by introducing conditioned air into the chamber by convection. The thermal conditioner includes a blower introducing conditioned air through the chamber. The thermal conditioner can be a thermoelectric device in combination with a fan.
[0015] In another embodiment, the invention relates to a reclosable cup holder comprising a housing defining a cup-receiving chamber having an access opening through which a cup can be inserted or removed. A cup holder is located within the chamber for supporting a cup placed within the chamber. A see-through cover is movably mounted to the housing for movement between a closed position, where the cover closes the access opening, and an opened position, where the cover is removed from the access opening. The movable cover preferably comprises multiple segments that telescopically nest when opened.
[0016] In yet another embodiment, the invention relates to a method for controlling the temperature of a beverage held by a beverage container temporarily stored in a size-adjustable beverage holder located within a chamber of a housing in a motor vehicle. The method comprises adjusting the size of the size-adjustable beverage holder to accommodate the beverage container to be placed in the chamber; placing the beverage container in the size-adjustable beverage holder; and introducing thermally conditioned air into the chamber to control the temperature of the beverage in the beverage container at a temperature above or below the ambient air temperature within the vehicle interior.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In the drawings:
[0018] [0018]FIG. 1 is a perspective view of a beverage container holder according to the invention shown in the preferred environment of a console suitable for placement within the passenger compartment of a vehicle, with the beverage container holder comprising a chamber for receiving one or more beverage containers, a movably resizing element withdrawn from the chamber, a chamber cover in the open position, and a storage recess with a storage cover in a closed position.
[0019] [0019]FIG. 2 is a perspective view identical to FIG. 1 except that the resizing element is shown overlying the chamber.
[0020] [0020]FIG. 3 is a perspective view identical to FIG. 1 except that the cover is shown in the closed position.
[0021] [0021]FIG. 4 it is a bottom perspective view of the console of FIG. 1 and illustrating the housing structure forming the chamber and the storage recess, and a convection airflow generator for thermally conditioning air introduced into the chamber.
[0022] [0022]FIG. 5 is a longitudinal sectional view of the console of FIG. 1 and illustrating the relationship between the chamber, storage recess, convection airflow generator, chamber cover, and storage recess cover.
[0023] [0023]FIG. 6 is a sectional view taken along line 6 - 6 of FIG. 5 and illustrating the housing structure forming the chamber and the storage recess.
[0024] [0024]FIG. 7 is a sectional view taken along line 7 - 7 of FIG. 5 except the chamber cover is shown in the open position to better illustrate the resizing element in the withdrawn position.
[0025] [0025]FIG. 8 is an exploded view of the convection airflow generator shown in FIG. 4.
[0026] [0026]FIG. 9 is a perspective view similar to FIG. 1 and illustrating the placement of a bottle-type beverage container into the beverage container holder according to the invention.
[0027] [0027]FIG. 10 is a perspective view similar to FIG. 2 and illustrating the placement of a cup-type beverage container into the beverage container holder according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] [0028]FIG. 1 generally illustrates a console 10 incorporating a thermal conditioning beverage container holder 12 according to the invention in combination with an optional general storage compartment 14 . The console 10 comprises a housing 16 in which both the thermal conditioning beverage container holder 12 and the general storage compartment 14 are formed. The console 10 discloses one environment in which the thermal conditioning container holder 12 can be used and should not be considered limiting to the invention.
[0029] Referring to FIGS. 1 - 4 generally and FIG. 5 specifically, the general storage compartment will be described in terms of the housing 16 , which comprises a well 20 that defines a storage recess 22 for the general storage compartment 14 . The well 20 terminates in an upper lip 24 that defines an opening through which access to the general storage recess 22 is obtained. A cover 28 is movably mounted to the housing 16 to enable the selective closure of the general storage recess 22 . It is preferred that the cover 28 be soft or padded so that it may function as an armrest or other support for an occupant in the vehicle.
[0030] The thermal conditioning beverage container holder 12 comprises a well 40 defining at least a portion of a chamber 42 for holding a portion of a beverage container and a movable lid 44 for selectively covering the chamber 42 . The well 40 is integrally formed with the housing 16 and includes a bottom wall 46 from which extends a peripheral wall 48 , which terminates in an outwardly turned lip 50 . A portion of the lip 50 transitions into a vertical face 52 . The vertical face 52 , in combination with the lip 50 , defines an access opening 54 in the housing 16 for the well 40 , which is selectively closed by movement of the cover 44 . The volume bounded by the cover 44 when closed can also be considered part of the chamber 42 as it is subject to the same air flow as the chamber 42 .
[0031] The cover 44 preferably comprises a series of U-shaped segments 60 , each of which is of a size to nest relative to each other in the opened position as shown in FIGS. 1 and 2, while still permitting the closure of the access opening 54 as shown in FIGS. 3 - 5 . Each of the U-shaped segments 60 terminates in a pair of hubs 62 in which is formed an opening 64 sized to receive a mounting shaft 66 , which is affixed to the housing 16 via spaced shaft mounts 67 integrally formed in the housing 16 at the junction of the lip 50 and the vertical face 52 , and which leave the shaft exposed therebetween. A lock washer secured to the mounting shaft 66 prevents the removal of the hub 62 from the mounting shaft 66 . Each of the segments 60 can be made from a transparent or translucent material that enables the user to see through the cover 44 and view the contents stored within the chamber 42 .
[0032] As illustrated, the smallest or innermost of the segments 60 functions as a control segment to affect the movement of all of the segments between the open and closed position. The innermost segment 60 is moved from a position adjacent the lip 50 to a position adjacent the vertical face 52 when moving the cover 44 from the opened position to the closed position. Looking at FIG. 5, each of the segments 60 includes a catch 61 that physically couples with the adjacent segments 60 to ensure that each of the segments 60 sequentially follows the movement of the innermost segment 60 from the closed to the opened position.
[0033] Although the cover is illustrated with the smallest segment functioning as the control segment, it is within the scope of the invention for the segments to be arranged such that the largest or outermost segment 60 functions as the control segment. In such a configuration, the user will physically move the outermost segment 60 to effect the movement of the cover between the opened and closed positions.
[0034] It is also within the scope of the invention for any other suitable type cover to be used instead of the multi-segmented lid as shown. Other suitable lids would include a single-piece lid, a tambour roll-top lid, or a flexible, collapsible cover for example.
[0035] The thermal conditioning beverage container holder 12 further comprises resizing elements used to accommodate various sizes of beverage containers for both differences in the vertical size and in the transverse cross-sectional area size. One resizing element comprises recess 74 formed in the bottom wall 42 of the well 40 . As best seen in FIGS. 4 - 6 , the recesses 74 are surrounded by a portion of the bottom wall 46 . A beverage container with a base having a larger cross-sectional area can be received on the bottom wall 46 than can be received within the recesses 74 . Thus, the recesses 74 in the bottom wall 46 function as resizing elements. Moreover, the nature of the recesses 74 , in that they will receive a portion of the beverage container base within the recess, aid in stabilizing the beverage container. Beverage containers too large in size for their bottom to be received within the recesses 74 will naturally be stabilized by the peripheral wall 48 surrounding the bottom wall 46 .
[0036] It is within the scope of the invention for the recesses 74 to comprise multiple or nested recesses, with each smaller recess preferably located within the circumference of a larger recess and having a slightly greater depth. The shape of such nesting recesses would have a stair step profile at its outer ends.
[0037] A second resizing element is a movable support plate 78 in which are formed multiple openings 80 . Each opening 80 is countersunk with a recessed surface 81 having a diameter larger than the diameter of the opening 80 . The support plate 78 includes a finger 82 having an opening through which the shaft 66 is slidably received to thereby pivotally mount the plate 78 to the housing 16 and permit the movement of the plate 78 between a withdrawn position as illustrated in FIG. 1, where the movable plate does not overlie the chamber 42 , and a use position, where the movable plate 78 overlies the chamber 42 as shown in FIG. 2. In the withdrawn position, the movable plate 78 is preferably located adjacent the vertical face 52 . A catch 83 on the finger 82 interacts with a latch 85 on the vertical face 52 to hold the movable plate 78 in the withdrawn position. Preferably, the catch 83 and latch 85 will be a hook and loop fastener. In the use position, the movable plate 78 overlies the chamber 42 such that the plate openings 80 are located within the interior of the chamber 42 and spaced from the bottom wall 46 .
[0038] The plate 78 can also include a stop 84 that abuts the lip 50 when the plate 78 is in the use position to effectively stop the movement of the plate and fix the plate in the use position. Similarly, the finger 82 is received within a channel 86 in the lip 50 to also limit the continued rotation of the plate 78 from the withdrawn position to the use position.
[0039] The plate openings 80 preferably have a smaller area than the recesses 74 formed in the bottom wall 46 so that the plate 78 can be used to accommodate even smaller-size cups than the recesses 74 . Unlike the recesses 74 in the bottom wall 46 , the openings 80 are sized to support beverage containers not by supporting the bottom of the container but by supporting the sidewall of the container after the base has been inserted through the plate openings 80 . Because of this structure, beverage containers supported by the plate 78 will be held higher within the chamber 42 than beverage containers supported by the bottom wall 46 .
[0040] Also, the recessed surfaces 81 will permit shorter cups such as coffee mugs with handles to be supported thereon, over the opening 80 . This configuration enables such a cup to be easily grasped without having to reach into the well 40 .
[0041] It should be noted that the recesses 74 could be openings like the openings 80 in the plate 78 . However, to prevent the high loss of conditioned air from the chamber 42 , it is preferred that the bottom wall 46 use recesses instead of openings.
[0042] Referring to FIGS. 5 - 8 , the thermal conditioning container holder 12 further comprises a convection airflow generator 88 comprising thermal conditioner 90 and a blower for circulating the thermally conditioned air. The convection airflow generator 88 is in fluid communication with the chamber 42 to supply conditioned air to the chamber 42 to help control the temperature of a beverage in the beverage container. It is preferred that the thermal conditioner 90 be capable of thermally conditioning the air by either heating or cooling the air as desired. However, it is within the scope of the invention for the thermal conditioner 90 to thermally condition the air by only heating or cooling, not both.
[0043] As generally illustrated in FIGS. 5 - 7 and specifically shown in FIG. 8, the preferred form of the thermal conditioner 90 is a thermoelectric device, which for this embodiment is the simplest contained unit. Such thermoelectric devices are well known and will not be described in detail since their construction and operation are well known. Super Cool AB of Sweden manufactures thermoelectric devices suitable for the invention. In general, the thermoelectric device comprises a thermoelectric element 92 having a traditional bicomponent structure, with heat sinks 94 , 95 mounted on either side of the thermoelectric element 92 .
[0044] A blower in the form of corresponding fans 96 , 97 is mounted to each of the heat sinks 94 , 95 , respectively. The thermoelectric device and the fans 96 , 97 are contained within a housing comprising first and second halves 98 , 99 each of which includes outlets 100 . Brackets 102 mount the thermoelectric element 92 to one of the housing halves 98 , 99 . Depending on the direction of the current flow through the thermoelectric element 92 , one of the heat sinks 94 , 95 will be cooled and the other will be heated. The fans 96 , 97 will circulate air over the heat sinks 94 , 95 . The housing 98 also includes an inlet opening 103 intermediate the outlets 100 , 101 .
[0045] The housing 98 is disposed between the thermoelectric device and the peripheral wall 48 . The outlets 100 in the housing 98 are aligned with corresponding supply vents 104 in the peripheral wall 48 of the well 40 , and the inlet opening 103 is aligned with corresponding return vents 106 in the peripheral wall 48 . This structure establishes fluid communication between the thermal conditioner 90 and the chamber 42 . The fan 96 is preferably arranged or a baffle is employed to create a recirculating airflow path between the thermal conditioner 90 and the chamber 42 , whereby the fan 96 draws air from the chamber 42 through the return air vents 106 to be conditioned by the thermal conditioner 90 . The conditioned air is then supplied to the chamber through the supply vents 104 . The direction of travel of the recirculating airflow is immaterial.
[0046] In a similar manner, air is directed to and away from the other side of the thermal conditioner 90 . Looking at FIGS. 1 - 6 , a back wall 110 of the housing 16 has a series of inlet openings 112 . A conduit 114 runs from the inlets openings 112 , beneath the general storage recess 22 to the fan second housing half 99 from which the fan 97 draws air and directs it toward the heat sink 95 . Air from the heat sink 95 is then expelled to atmosphere through exhaust vents 116 in the side of the housing 16 . The exhaust air may be conducted by way of side conduits 118 extending between the thermal conditioner 90 and the exhaust vents 116 .
[0047] The thermal conditioner 90 can thus be used to heat or cool the chamber 42 by convection in that the thermoelectric element 92 can heat or cool the heat sink 94 to condition the temperature of the air surrounding the heat sink 94 , and the fan 96 introduces the conditioned air into the chamber 42 . The thermal conditioner 90 , in combination with the fan 96 , forms the convection air flow generator 88 .
[0048] Other types of convection air flow generators can be used. For example, a traditional refrigeration circuit comprising a compressor, evaporator, and condenser in combination with a heating element can form the thermal conditioner of an alternative convection air flow generator. A fan can be used to force the air into the chamber 42 in the same manner as described above. Additionally, the HVAC system of the vehicle can be used to supply the conditioned air. Although the stand-alone refrigeration unit in combination with a heating element and the HVAC system can technically be used as part of or complete alternatives to the convection flow generator of the invention, they are not preferred and are not highly desirable, self-containment and compactness is valued over cooling performance. Each has disadvantages as compared to the thermoelectric device. Most notably, the thermoelectric device is self-contained and compact, easily fitting into the interior of the console. It does not require all of the moving parts of the stand-alone refrigeration system, nor does it require the special ducting that the vehicle HVAC system would need to supply the chamber 42 . The vehicle HVAC system is also limited in that it can only supply hot or cold air as required by the passenger in the vehicle, which may not be what is needed for the beverage. For example, if a cold drink is placed in the beverage container holder and it is wintertime, the passenger is likely to have the HVAC emitting heated air, which will warm the beverage, not keep it chilled.
[0049] The operation of the container holder 12 will be described with reference to FIG. 9. In operation, the user initially moves the cover 44 to the open position, if it is not already in the open position. The user will then adjust the beverage container holder to accommodate the desired beverage container size. For example, if the user is going to place a straight-walled bottle of the type commonly used for water or sports drinks in the container holder 12 , the user will typically move the plate 78 to the withdrawn position and place the bottle within the chamber 42 until the bottom of the bottle abuts the bottom wall 46 of the well 40 .
[0050] The depth of the chamber 42 as defined by the well 40 is sufficient to maintain such bottles, and most containers for that matter, in a stable position. If the transverse cross-sectional area of the bottle is small enough to be received within the recess 74 , the bottom of the bottle will so be received, thereby further stabilizing the bottle. If the bottom of the bottle is too large to be received within the recess 74 , the bottle bottom will naturally rest on the bottom wall 46 .
[0051] If the bottle has a transverse cross-sectional area that can be received through the openings 80 in the plate 78 , the user need not move the plate 78 to the withdrawn position. Instead, the user can move the plate 78 to the use position and insert the bottle through one of the openings 80 , which will further stabilize the bottle. This is especially useful for many bottles used for water and sports drinks, which tend to have a much greater height and a smaller transverse cross-sectional area than a traditional cup, rendering them more likely to tip over.
[0052] It should be noted that this description of the insertion of a bottle into the cup holder 12 also applies to any other type of beverage container, including a tapered cup, to the extent the beverage container can fit within the chamber 42 or through the plate openings 80 as described.
[0053] Assuming the beverage in the bottle is of the type that is typically served chilled, the thermal conditioner 90 will be operated to convect chilled air to the chamber 42 to control the temperature of the beverage in the bottle in a chilled condition.
[0054] It is preferred that the user maintain the cover 44 in the closed position when access is not needed to the beverage container since the closed cover will enhance the efficiency of the thermal conditioner 90 by maintaining the chilled air within the chamber 42 .
[0055] While no controller is disclosed for controlling the operation of the thermal conditioner, including the heating or cooling setting along with the starting and stopping of the thermal conditioner 90 , it is contemplated that a simple controller permitting at least the control of the heating or cooling mode will be provided. The user interface for such a controller can be located on the console or on the dashboard of the vehicle. The type of controller and its location is not germane to the invention. Suitable controllers already exist or are easily designed. For example, a controller suitable for the invention is a double pole, double throw, polarity reversing switch from Eaton Corporation of the type commonly used in automotive applications.
[0056] [0056]FIG. 10 illustrates the operation of the container holder 12 when used to hold a cup, typically of the tapered variety, which is normally used to hold heated beverages, such as coffees and the like. These types of beverage containers are generally tapered and have a short height. While these types of cups could be placed directly in the chamber 42 in the same manner described for the bottle, it is anticipated that the depth of the chamber 42 will be sufficient that it will be difficult for the user to insert and remove the cup from the chamber 42 . Therefore, it is contemplated that when using such smaller cups, the user will prefer to have the cups supported by the plate 78 instead of placing the cups within the chamber 42 .
[0057] To support the cup as described, the user will move the plate 78 into the use position, if it is already not in the use position. The user will then insert the bottom portion of the cup into one of the plate openings 80 until the sidewalls of the cup rest against the end of the plate 78 defining the openings 80 . As can be seen in FIG. 10, in this position, a lower portion of the cup is received within the chamber 42 and the upper portion of the cup extends above the plate 78 . The user can then close the cover 44 .
[0058] For the traditional cups, it is also preferred that the cover 44 is kept closed when access is not needed to the cup. This is especially true when the cup contains a beverage that is typically served heated. Since heated air will be convected into the chamber 42 for a hot beverage, the heated air, which will naturally rise, will tend to escape from the chamber 42 when the cover is in the opened position. Maintaining the cover in the closed position will enhance the efficiency of the thermal conditioner 90 and its ability to maintain the temperature of the beverage as desired.
[0059] The invention takes advantage of the tendency of heated air to rise and the likelihood that heated beverages are generally served in smaller cups by locating the plate 78 at an elevated position relative to the chamber 42 . By so positioning the plate 78 , the cups of an appropriate size to fit within the plate openings 80 are maintained in an elevated position where the rising heated air will tend to collect when the cover is closed. Thus, the portion of the housing between the chamber 42 and the cover 44 in the closed position effectively becomes part of the chamber 42 and is also treated with thermally conditioned air.
[0060] While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit. | A beverage container holder that is adjustable to accommodate various sizes of beverage containers, including containers of different heights and diameters for both tapered-wall containers and straight-wall containers. The beverage container includes a convection air flow generator for supplying conditioned air around the beverage containers to control the temperature of the beverage within the beverage container. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to heat protection elements made of quasicrystalline aluminum alloys.
2. Description of the Prior Art
Heat barriers are assemblies of one or more materials intended to limit the heat transfer towards or from parts and components of fittings in many household or industrial devices. It is possible, for example, to mention the use of heat barriers in heating or cooking devices, smoothing irons where the hot part is attached to the body and near heat insulation; in automobiles, at a number of points such as the turbocompressor, the exhaust system, insulation of the cabin, and the like; and in aeronautics, for example on the rear part of compressors and jet engines.
Heat barriers are sometimes employed in isolation in the form of screening, but very frequently they are used directly in combination with the source of heat or the part to be protected for reasons of mechanical behavior. Thus, use is made of sheets of mica, of ceramic plates and the like in electrical household appliances by fitting them by screwing or adhesive bonding, or else of sheets of agglomerated glass wool which are supported by a sheet of metal. A particularly advantageous process for attaching a heat barrier to a part, in particular to a metal part, consists in depositing onto a substrate the material forming the barrier in the form of a layer of thickness determined by a thermal-spraying technique such as, for example, plasma spraying.
It is very frequently recommended to use the heat barrier, which may furthermore comprise a number of layers, in combination with other materials which are also deposited as a layer by thermal spraying. These other materials may be intended to provide the barrier with protection against external actions such as, for example, mechanical impacts, a corrosive environment and the like, or else to make it easier to bond to the underlying substrate. This point is particularly important in the case of heat barriers operating in heat cycling conditions or at high temperature. The mechanical stresses which then exist at the interface with the substrate and result from the differences in the thermal expansion coefficients of the substrate and of the deposit quickly lead to damage of the barrier by shearing, when they do not prohibit its use. To overcome this disadvantage, use is frequently made of an intermediate deposit, called bond coat, which becomes plastic in the working temperature region of the barrier, and this eliminates the stresses at the barrier interface.
The material most frequently employed in aeronautics to form heat barriers is yttriated zirconia, which withstands very high temperatures. The deposition of the zirconia is carried out by plasma spraying using a conventional technique starting with the powdered material. Zirconia has a low thermal diffusivity (α=10 -6 m 2 /s). However, it has a relatively high specific mass ρ, and this constitutes a disadvantage in certain applications; moreover, some of its mechanical properties, such as hardness and resistance to wear and to abrasion, are low.
Other materials are employed as heat barrier. Mention may be made of alumina, which has a specific mass lower than that of zirconia, and a diffusivity and specific heat which are higher than that of zirconia, but whose mechanical properties are not satisfactory. It is also possible to mention stainless steels and some refractory steels which offer heat insulation properties but which have a high specific mass.
SUMMARY OF THE INVENTION
The objective of the present invention is to provide heat protection elements in the form of heat barrier or in the form of bond coat for heat barriers, exhibiting good thermal insulation properties, good mechanical properties, a low specific mass, good resistance to corrosion, especially to oxidation, and great ease of processing.
An element for heat protection of a substrate of the present invention is characterized in that it consists of a material which is deposited on the substrate by thermal spraying and which consists essentially of a quasicrystalline aluminum alloy exhibiting a thermal diffusivity, measured at ambient temperature, which is lower than 2.5×10 -6 m 2 /s, and a thermal diffusivity measured in the temperature range 650°-750° C. which does not exceed the thermal diffusivity measured at ambient temperature by more than a factor of 3. The diffusivity at ambient temperature is preferably lower than 1.6×10 -6 m 2 /s.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the change in as α function of the temperature, T, for heating, represented by black squares, and cooling, represented by white squares, Al 65 Cu 20 Fe 10 Cr 5 (alloy 3).
FIG. 2 shows the change in α as a function of the temperature, T, for heating the alloy Al 63 .5 Cu 24 Fe 12 .5 (alloy 5) in the rhombohedral approximant, (a), and icosahedral phase, (b), states.
FIG. 3 shows the change in α as a function of the temperature, T, for the alloy heating Al 63 Cu 17 .5 Co 17 .5 Si 2 (alloy 7). The measurements recorded during the first heating are shown by a circle. The measurements recorded during the first cooling are shown by a black disk. The measurements recorded during the second heating are shown by a square.
FIG. 4 shows a sample of the copper cylinder comprising a coating 2 and provided with a central thermocouple 3 and a side thermocouple 4, both being inserted as far as half the length of the cylinder.
FIG. 5 shows a hollow tube 5 through which a flow of hot air 6 is passed and which is provided with three thermocouples indicated by T1, T2 and T3.
FIG. 6 shows the change in surface temperature of samples as a function of time.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the present text "quasicrystalline alloy" is intended to mean an alloy consisting of one or a number of quasicrystalline phases which are either quasicrystalline phases in the strict sense, or approximating phases. Quasicrystalline phases in the strict sense are phases which have symmetries of rotation that are normally incompatible with the symmetry of translation, that is to say symmetries with an axis of rotation of order 5, 8, 10 and 12, these symmetries being disclosed by radiation diffraction. By way of example there may be mentioned the icosahedral phase of point group m35 (cf. D. Shechtman, I. Blech, D. Gratias, J. W. Cahn, Metallic Phase with Long-Range Orientational Order and No Translational Symmetry, Physical Review Letters, Vol. 53, No.20, 1984, pages 1951-1953) and the decagonal phase of point group 10/mmm(cf. L. Bendersky, Quasicrystal with One Dimensional Translational Symmetry and a Tenfold Rotation Axis, Physical Review Letters, Vol. 55, No.14, 1985, pages 1461-1463). The x-ray diffraction pattern of a true decagonal phase has been published in "Diffraction approach to the structure of decagonal quasicrystals, J. M. Dubois, C. Janot, J. Pannetier, A. Pianelli, Physics Letters A 117-8 (1986) 421-427".
The approximating phases or approximating compounds are true crystals insofar as their crystallographic structure remains compatible with the symmetry of translation, but which, in the electron diffraction pattern, exhibit diffraction figures whose symmetry is close to the axes of rotation 5, 8, 10 or 12.
Among these phases it is possible to cite as an example the orthorhombic phase O 1 , characteristic of an alloy which has the atomic composition Al 65 Cu 20 Fe 10 Cr 5 , the lattice constants of which are: a o .sup.(l) =2.366, b o .sup.(1) =1.267, c o .sup.(1) =3.252, in nanometers. This orthorhombic phase O 1 is said to be approximating the decagonal phase. It is furthermore so close to it that its x-ray diffraction pattern cannot be distinguished from that of the decagonal phase.
It is also possible to cite the rhombohedral phase with constants a R =3.208 nm, α=36°, present in the alloys of composition close to Al 64 Cu 24 Fe 12 in number of atoms (M. Audier and P. Guyot, Microcrystalline AlFeCu Phase of Pseudo Icosahedral Symmetry, in Quasicrystals, eds. M. V. Jaric and S. Lundqvist, World Scientific, Singapore, 1989). This phase is a phase approximating the icosahedral phase.
It is also possible to mention orthorhombic phases O 2 and O 3 with corresponding constants a o .sup.(2) =3.83, b o .sup.(2) =0.41, c o .sup.(2) =5.26 and a o .sup.(3) =3.25, b o .sup.(3) =0.41, c o .sup.(3) =9.8, in nanometers, which are present in an alloy of composition Al 63 Cu 17 .5 Co 17 .5 Si 2 in number of atoms or else the orthorhombic phase O 4 with constants a o .sup.(4) =1.46, b o .sup.(4) =1.23, c o .sup.(4) =1.24, in nanometers, which is formed in the alloy of composition Al 63 Cu 8 Fe 12 Cr 12 , in number of atoms.
It is further possible to mention a phase C, of cubic structure, very frequently observed as coexisting with the approximating or true quasicrystalline phases. This phase, which is formed in some Al--Cu--Fe and Al--Cu--Fe--Cr alloys, consists of a superstructure by chemical ordering of the alloy elements on the aluminium sites, the latter forming a Cs--Cl type structure with a lattice constant a 1 =0.297 nm. A diffraction pattern of this cubic phase has been published (C. Dong, J. M. Dubois, M. de Boissieu, C. Janot; Neutron diffraction study of the peritectic growth of the Al 65 Cu 20 Fe 15 icosahedral quasicrystal; J. Phys. Condensed Matter, 2 (1990), 6339-6360) for a sample of pure cubic phase and of composition Al 65 Cu 20 Fe 15 , in number of atoms.
It is also possible to mention a phase H of hexagonal structure which derives directly from the C phase as demonstrated by the epitaxy relationships observed by electron microscopy between crystals of the C and H phases and the simple relationships which link the constants of the crystal lattices, namely a H =3√2a 1 /√3 (to within 4.5%) and c H =3√3a 1 /2 (to within 2.5%). This phase is isotypical with a hexagonal phase, written as ΦAlMn, discovered in Al--Mn alloys containing 40% by weight of Mn [M. A. Taylor, Intermetallic phases in the Aluminium-Manganese Binary System, Acta Metallurgica 8 (1960) 256].
The cubic phase, its superstructures and the phases which derive therefrom constitute a class of phases approximating the quasicrystalline phases of nearby composition.
Among the quasicrystalline alloys constituting the heat protection elements of the present invention there may be mentioned those which have one of the following nominal compositions:
Al a Cu b Fe c J e I g , (I), in which Y denotes at least one element chosen from V, Mo, Ti, Zr, Nb, Cr, Mn, Ru, Rh, Ni, Mg, W, Si and the rare earths, I denotes the unavoidable production impurities, 0≦g≦2, 14≦b≦30, 7≦c≦20, 0≦e≦10, c+e≧10 and a+b+c+e+g=100% in number of atoms;
Al a Cu b Fe c X d J e I g , (II), in which X denotes at least one element chosen from B, C, P, S, Ge and Si, Y denotes at least one element chosen from V, Mo, Ti, Zr, Nb, Cr, Mn, Ru, Rh, Ni, Mg, W, Hf, Ta and the rare earths, I denotes the unavoidable production impurities, 0≦g≦2, 14≦b≦30, 7≦c≦20, 0≦d≦5, 21≦b+c+e≦45, and a+b+c+d+e+g=100% in number of atoms;
Al a Pd b Mn c X d J e T f I g (III), in which X denotes at least one metalloid chosen from B, C, Si, Ge, P, and S; Y denotes at least one metal chosen from Fe, Mn, V, Ni, Cr, Zr, Hf, Mo, W, Nb, Ti, Rh, Ru, Re, Ta; T is at least one rare earth; I denotes the unavoidable production impurities; with a+b+c+d+e+f+g=100 atom %; 15≦b≦25; 6≦c≦16; 21≦b+c+e≦45; 0≦f≦4; 0≦g≦2; 0≦d≦5;
Al a Cu b Co c X d J e T f I g (IV) , in which X denotes at least one metalloid chosen from B, C, Si, Ge, P and S; Y denotes at least one metal chosen from Fe, Mn, V, Ni, Cr, Zr, Hf, Mo, W, Nb, Ti, Rh, Ru, Re; T is at least one rare earth; I denotes the unavoidable production impurities; with a+b+c+d+e+f+g=100 atom %; 14≦b≦27; 8≦c≦24; 28≦b+c+e≦45; 0≦f≦4; 0≦d≦5; 0≦g≦2;
Al a X d J e I g , (V), in which X denotes at least one element chosen from B, C, P, S, Ge and Si, Y denotes at least one element chosen from V, Mo Cr, Mn, Fe, Co, Ni, Ru, Rh and Pd, I denotes the unavoidable production impurities, 0≦g≦2, 0≦d≦5, 18≦e≦29, and a+d+e+g=100% in number of atoms.
The materials employed for the production of heat protection elements according to the present invention have thermal diffusivity values α close to 10 -6 m 2 /s which are very comparable to thermal diffusivity of zirconia. Bearing in mind the lower specific mass ρ of these materials, the thermal conductivity λ=αρCp in the vicinity of the ambient temperature does not exhibit any significant difference in relation to that of zirconia. The quasicrystalline alloys are therefore suitable substitutes for replacing many heat barrier materials, and in particular zirconia, in comparison with which they offer advantages of low specific mass and of excellent mechanical properties insofar as hardness and improved resistance to wear, to abrasion, to scratching and to corrosion are concerned.
The diffusivity of the materials constituting the heat protection elements of the present invention is reduced when the porosity of the materials increases. The porosity of a quasicrystalline alloy can be increased by an appropriate heat treatment. Thus, for example, the alloy Al 63 .5 Cu 24 Fe 12 .5, produced in the crude state, has a porosity of the order of 3%, measured on a metallographic section by conventional image analysis. After a heat treatment for three hours at 850° C. the porosity is of the order of 8%. It is particularly advantageous to employ quasicrystalline alloys which have a porosity higher than 10%.
The materials constituting the heat protection elements of the present invention may contain a small proportion of heat-conductive particles, for example crystals of metallic aluminum. The heat conduction of the material will be dominated by the conduction properties of the matrix as long as the particles do not coalesce, that is to say that their proportion by volume remains below the percolation threshold. In the case of approximately spherical particles which have a narrowly distributed radius this threshold lies in the region of 20%. This condition implies that the material constituting the heat protection element should contain at least 80% by volume of quasicrystalline phases as defined above.
At temperatures which are lower than approximately 700° C. the heat protection elements can be employed as heat barriers. Such temperature conditions correspond to most of the household applications or those in the automobile field. In addition, they are highly capable of withstanding the stresses due to the expansion of the support, and their expansion coefficient is intermediate between that of metal alloys and that of insulating oxides. In the case of temperatures which are higher than approximately 600° C. the quasicrystalline alloys constituting heat barriers may preferably contain stabilizing elements chosen from W, Zr, Ti, Rh, Nb, Hf and Ta. The content of stabilizing element is lower than or equal to 2% in number of atoms.
The heat barriers of the present invention may be multilayer barriers which have an alternation of layers of materials which are good heat conductors and of layers of materials which are poor conductors (quasicrystalline alloys). Such structures form, for example, abradable heat barriers.
For applications in which the temperatures reach values higher than approximately 600° C., the heat protection elements of the present invention can be employed as bonding underlayer for a layer which is used as heat barrier and consists of a material of the prior art such as zirconia. In these temperature ranges the materials constituting the heat protection elements of the present invention become superplastic. They therefore correspond well to the conditions of use which are required for the production of a bonding underlayer, while being capable themselves of taking part in the insulation of the substrate. Thus, the heat protection elements of the present invention can be employed to within a few tens of degrees of the melting point of the material of which they consist. This limit lies in the region from 950° C. to 1200° C. depending on the composition
A heat protection element of the present invention is produced by depositing the material(s) of which it consists as one or more layers on a substrate. The quasicrystalline material is deposited by a thermal spraying process, for example with the aid of an oxygen-gas torch, a supersonic torch or a plasma torch.
EXAMPLE 1
Different bulk samples of the alloys whose composition is given in Table 1 below, were produced by melting the pure elements in a high-frequency field under an argon atmosphere in a cooled copper crucible. The total mass thus produced was between 50 g and 100 g of alloy. The melting temperature, which depends on the composition of the alloy, is in the temperature range situated between 950° and 1200° C. While the alloy was kept molten, a solid cylindrical test piece 10 ±0.5 mm in diameter and a few cm in height was formed by sucking the liquid metal into a quartz tube. The rate of cooling of this sample was close to 250° C. per second. This sample was then cut up with a diamond saw to obtain cylindrical test pieces approximately 3 mm in thickness. The opposite faces of each cylinder were polished mechanically under water, great care being taken to guarantee their parallelism. The structural state of the test pieces was determined by x-ray diffraction and by electron microscopy. All the samples selected (samples 1 to 8) contained at least 90% by volume of quasicrystalline phase according to the definition given above.
EXAMPLE 2
The thermal diffusivity α, the specific mass ρ and the specific heat Cp were determined in the vicinity of the ambient temperature for the samples prepared above.
The thermal conductivity is given by the product λ=αρCp.
The thermal diffusivity was determined with the aid of a laboratory device using the laser flash method in combination with an Hg--Cd--Te semiconductor detector. The laser was employed to provide pulses of power between 20 J and 30 J of 5×10hu -4s duration, to heat the front face of the test piece and the semiconductor thermometer was used to detect the thermal response on the opposite face of the test piece. The thermal diffusivity was deduced from the experiments by the method described in "A. Degiovanni, High Temp.--High Pressure, 17 (1985) 683.
The specific heat of the alloy was determined in the 20°-80° C. temperature range with a SETARAM scanning calorimeter.
The thermal conductivity λ is deduced from the preceding two measurements, with the knowledge of the specific mass of the alloy, which was measured using Archimedes method by immersion in butyl phthalate maintained at 30° C. (±0.1° C.).
The values obtained are reported in Table 1. By way of comparison, this table contains the values relating to a few materials of the prior art, some of which are known as a heat barrier (samples 9 to 12).
TABLE 1__________________________________________________________________________ % by volume of α ρ Cp λ = αρCp majorityComposition m.sup.2 s.sup.- × 10.sup.6 kg m.sup.-3 J kg.sup.-1 /K.sup.-1 W kg.sup.-1 K.sup.-1 phase__________________________________________________________________________1 Al.sub.13 Fe.sub.4 1.5 3870 610 2.95 100% m2 Al.sub.65.5 Cu.sub.18.5 Fe.sub.8 Cr.sub.8 1.05 4300 620 2.8 100% O/D3 Al.sub.65 Cu.sub.20 Fe.sub.10 Cr.sub.5 1.55 ± 0.1 4260 ± 150 680 4.5 100% O/D4 Al.sub.63.5 Cu.sub.24 Fe.sub.12.5 0.85 ± 0.02 3950 ± 200 600 2 100% R/I 3% porosity5 Al.sub.63.5 Cu.sub.24 Fe.sub.12.5 0.50 ± 0.02 3700 ± 200 590 1.1 100% R/I 8% porosity6 Al.sub.61.3 Cu.sub.23.6 Fe.sub.11.6 B.sub.3.5 1.15 3800 600 2.6 >90% R/I7 Al.sub.63 Cu.sub.17.5 Co.sub.17.5 Si.sub.2 1.3 ± 0.06 4200 ± 200 675 3.7 >95% O'/D'8 Al.sub.71 Pd.sub.19 Mn.sub.10 1.0 100% I'9 Al fcc 90-100 2700 900 23010 Al.sub.2 O.sub.3 8.5 3800 1050 3411 Stainless steel 4 7850 480 1512 ZrO.sub.2 --8%Y.sub.2 O.sub.3 0.8 5700 400 213 Al.sub.6 Mn 5.414 Al.sub.13 Si.sub.4 C.sub.14 7.415 Al.sub.5 Ti.sub.2 Cu 7.016 Al.sub.7 Cu.sub.2 Fe 6.217 Al.sub.2 Cu 14-17__________________________________________________________________________
In this table the symbols in the last column have the following meaning:
m: monoclinic approximant (P. J. Black, Acta Cryst. 8 (1955) 43)
O: orthorhombic approximants (C. Dong, J. M. Dubois, J. Materials Science, 26(1991), 1647
D: decagonal phase (L. Bendersky, Quasicrystal with One Dimensional Translational Symmetry and a Tenfold Rotation Axis, Physical Review Letters, vol. 55, No.14, 1985, pages 1461-1463).
R: rhombohedral approximant (M. Audier and P. Guyot, 3rd Int. Meeting on Quasicrystals, eds. J. Yacaman, World Scientific, Singapore, 1990).
I: icosahedral phase (D. Shechtman, I. Blech, D. Gratias, J. W. Cahn, Metallic Phase with Long-Range Orientational Order and No Translational Symmetry, Physical Review Letters, vol. 53, No.20, 1984, pages 1951-1953)
O': orthorhombic approximants (C. Dong et al, J. Mat. Science, vol.26, 1991, 1647)
D': decagonal phase (W. Steurer, K. H. Kuo, Phil. Mag. Letters, 62-3, 1990, 115-182
I': icosahedral phase L. X. He, et al., Phil. Mag. Lett. 61 (1990) 15)
These results reveal that, at ambient temperature, the thermal conductivity of the quasicrystalline alloys constituting the protection elements of the present invention (samples 1 to 8) is considerably lower than that of metallic materials (aluminum metal or tetragonal Al 2 Cu), which are given by way of comparison. It is lower by two orders of magnitude than that of aluminum and by one order of magnitude than that of stainless steel, usually considered to be a good thermal insulator. In addition, it is lower than that of alumina and quite comparable with that of zirconia doped with Y 2 0 3 , considered to be the archetype of thermal insulators in industry.
By way of comparison, the diffusivity of alloys 13 to 17 was determined. These alloys, which form definite aluminum compounds, have compositions close to those of the quasicrystalline alloys which can be employed for the protection elements of the present invention. However, they do not have the quasicrystalline structure defined above. In all cases their thermal diffusivity is higher than 5×10 -6 m 2 /s, that is to say much higher than that of the alloys adopted for the present invention.
EXAMPLE 3
The values of α have been recorded as a function of temperature up to 900° C.
Measurement of thermal diffusivity was performed by the method of Example 2. Each test piece was placed under a flow of purified argon in the center of a furnace heated by a Joule effect; the rate of temperature rise, programmed by computer, varied linearly at a rate of 5° C./min. All the samples in accordance with the present invention exhibit an approximately linear increase in α with temperature. The value of α determined at 700° C. is nearly double that measured at the ambient temperature. Similarly, the specific heat increases with temperature and reaches from 800 to 900 J/kg K at 700° C. The specific mass decreases by of the order of 1 to 2%, as shown by the measurements of thermal expansion or of neutron diffraction. Consequently, thermal conductivity remains lower than 12 W/m K, that is to say than the thermal conductivity of the stainless steels which are employed for some thermal insulation applications. Much better performance, however, is observed in the case of certain alloys: for example, in the case of the alloy Al 63 .5 Cu 24 Fe 12 .5 (alloy 4), λis 3.2 W/m K at 700° C.
FIGS. 1, 2 and 3 show, respectively, the change in as α function of the temperature T for different materials under the following conditions:
FIG. 1: the measurements recorded during the heating of the alloy Al 65 Cu 20 Fe 10 Cr 5 (alloy 3) are shown by black squares, those recorded during the cooling by white squares.
FIG. 2: heating in the case of the alloy Al 63 .5 Cu 24 Fe 12 .5 (alloy 5) in the rhombohedral approximant (a) and icosahedral phase (b) states. Above 860° C. the alloy is transformed into a mixture of crystalline phases--hence the increase in α--and then melts at about 950° C.
FIG. 3: Al 63 Cu 17 .5 Co 17 .5 Si 2 (alloy 7). The measurements shown by a circle were recorded during a first heating; those shown by a black disk were recorded during the first cooling and those shown by a square during a second heating. It appears that the diffusivity is reversible and varies between 1.3 and 2×10 -6 m 2 /s between 20° C. and 750° C.
EXAMPLE 4
The variation in the thermal expansion of the alloys Al 63 .5 Cu 24 Fe 12 .5 and Al 63 Cu 17 .5 Co 17 .5 Si 2 was measured. The corresponding thermal expansion curves reveal that the expansion coefficient shows very little dependence on temperature and has the value of 8×10 -6 /° C. in the first case mentioned and 11×10 -6 /° C. in the second case, these values being close to those for stainless steels.
EXAMPLE 5
The superplastic behavior of certain alloys capable of constituting the heat protection elements of the present invention was studied. Cylindrical test pieces 4 mm in diameter and 10 mm in length, with strictly parallel faces, were produced by the same method as those of Example 1 with the alloys Al 63 .5 Cu 24 Fe 12 .5 and Al 62 .5 Cu 18 .5 Fe 8 Cr 8 Si 3 . These test pieces were subjected to mechanical tests in compression on an Instrom machine. Tests were performed up to a load of 250 MPa, at a beam travel speed of 50 μm/min, the temperature being kept constant between 600° and 850° C. The alloys exhibit a superplastic behavior from 600° C. onwards.
EXAMPLE 6
Production of heat protection elements according to the invention and according to the prior art.
A first series of samples was produced. The substrate was a solid copper cylinder which had a diameter of 30 mm and a height of 80 mm and the coating was applied with the plasma torch by a conventional technique. Sample C0 is the uncoated copper cylinder. Sample C1 was coated over its whole surface with a 1-mm thick layer of the alloy Al 65 .5 Cu 18 .5 Fe 8 Cr 8 (alloy 2). Sample C6 comprises a layer of a material constituting the heat protection element of the present invention, used as bonding layer, and a layer of yttriated zirconia. Samples C3 and C4, used for comparison, comprise a layer of zirconia and a layer of alumina respectively.
Another series of samples was produced with, as support, a stainless steel tube which had a length of 50 cm, a diameter of 40 mm and a wall thickness of 1 mm (samples A0 to A2). In each case the support tube is coated at one of its ends over a length of 30 cm. In this latter case the deposits were produced with an oxygen-gas torch, except for the zirconia deposit of sample A2, which was produced with the plasma torch. Table 2 below gives the nature and the thickness of the layers for the different samples. The accuracy of the final thicknesses of the deposits was ±0.3 mm.
All the samples were provided with chromel-alumel thermocouples of very low inertia. FIG. 4 shows a sample of the copper cylinder type 1 comprising a coating 2 and provided with a central thermocouple 3 and a side thermocouple 4, both being inserted as far as half the length of the cylinder. FIG. 5 shows a hollow tube 5 through which a flow of hot air 6 is passed and which is provided with three thermocouples indicated by T1, T2 and T3 respectively, the first two being inside the tube and placed, respectively, at the beginning of the coated zone and at the end of the coated zone, and the third being on the surface of the coating.
EXAMPLE 7
Use of the protection elements as protection in relation to a flame.
Samples C0, C1, C3 and C6 were placed on their base on a refractory brick. Successive heat pulses 10 s in duration were applied to each test piece at 60-s intervals and the response of the thermocouples was recorded. These pulses were produced by the flame of a torch placed at a constant distance from the sample and pointed facing the thermocouple close to the surface. The flow rate of the combustion gases was carefully controlled and kept constant throughout the experiment. Two series of experiments were conducted: one with the test pieces initially at 20° C. and the other with the test pieces initially at 650° C.
Sample C0 makes it possible to define three parameters which summarize the results of the experiment, namely the maximum difference P in temperature between the two thermocouples, ΔT/Δt the rate of temperature rise the side thermocouple 4 during the pulse and the temperature increment ΔT produced in the center of the test piece (thermocouple 3). These data appear in Table 2. These results show that the protection elements of the present invention, employed as a heat barrier, have a performance which is at least equivalent to that of zirconia.
In samples C6 and A2 the heat protection elements of the present invention constitute an underlayer. It was found that the zirconia layer of sample C3 did not stand up to more than three heat pulses and was fissured from the first pulse onwards. In the case of sample C6, also subjected to a series of heat pulses, the surface temperature of the zirconia deposit, measured by a third thermocouple placed in contact with the deposit at the end of the tests, became stabilized at 1200° C. The experiment involved 50 pulses and sample C6 resisted without apparent damage, although the coefficient of expansion of copper is close to twice that of the quasicrystalline alloy, which would imply high shear stresses at the substrate/deposit interface, if the underlayer material did not become plastic. The heat protection elements of the present invention are therefore well suited for the production of bond coats, in particular for heat barriers.
TABLE 2__________________________________________________________________________ 20-100° C. 650-550° C. ΔT P ΔT P ±0.5° C. ΔT/Δt ±0.5° C. ±0.5° C. ΔT/Δt ±0.5° C.Coating material °C. °C./s °C. °C. °C./s °C.__________________________________________________________________________C0 none 27 2.85 5.4 22 2.3 <1C1 1 mm Al.sub.65.5 Cu.sub.18.5 Fe.sub.8 Cr.sub.8 25 2.7 3.8 11 1.1 6C6 0.5 mm Al.sub.65.5 Cu.sub.18.5 Fe.sub.8 Cr.sub.8 24 2.6 4.0 13 1.0 2.5 1 mm ZrO.sub.2 --8%Y.sub.2 O.sub.3C3 1 mm zirconia 24 2.75 4.7 14 1.5 2.3C4 1 mm alumina 27 2.7 6.5 25 3.0 8.2A0 none -- -- -- -- -- --A1 1.5 mm Al.sub.65.5 Cu.sub.18.5 Fe.sub.8 Cr.sub.8 -- -- -- -- -- --A2 0.3 mm Al.sub.65.5 Cu.sub.18.5 Fe.sub.8 Cr.sub.8 -- -- -- -- -- -- 1.2 mm ZrO.sub.2 --8%Y.sub.2 O.sub.3__________________________________________________________________________
EXAMPLE 8
Application of a heat protection element of the present invention to the insulation of a jet engine.
Samples A0 and A1 were employed to evaluate the suitability of the alloys of the invention for heat-insulating a device. A comparison was made in relation to the properties of a zirconia barrier provided with a bonding layer (sample A2). Each of the samples was equipped with 3 thermocouples T1, T2 and T3 as shown in FIG. 5. A stream of hot air at a constant flow rate was passed through the stainless steel tube forming the substrate of each sample. The temperature of the air at the entry, measured with the aid of the thermocouple T1, was 300±2° C. The surface temperature, measured with the aid of the thermocouple T3, was recorded as a function of time starting with the switching on of the hot air generator. Thermocouple T2 made it possible to verify that the transient conditions for establishing the hot air flow were identical in the case of all the measurements.
FIG. 6 shows the change in the surface temperature of each of the samples A0, A1 and A2 as a function of time. The surface temperature of sample A0 (without coating) exceeds that of the zirconia sample by approximately 35° C. at equilibrium. The heat protection elements of the present invention give results close to that for the zirconia layer, since a temperature difference of only 10° C. is measured between sample A1 (quasi-crystalline coating) and sample A2 (zirconia coating used as reference ). | An element for thermally protecting a substrate is deposited on the substrate and comprises a quasicrystalline aluminum alloy having a thermal diffusivity lower than 2.5×10 -6 m 2 /s at room temperature and a thermal diffusivity, within the temperature range 650°-750° C., which does not exceed its thermal diffusivity at room temperature by a factor greater than 3. The element may be used to provide heat barriers or bonding layers for substrates. The heat protection element, used in the form of a heat barrier or in the form of a bond coat for neat barriers, exhibits good thermal insulation properties, good mechanical properties, a low specific mass, good resistance to corrosion, and great ease of processing. Further, the invention is useful in limiting heat transfer towards or from parts and components of fittings in many household and industrial devices, for example, heating or cooking devices, smoothing irons, automobile components, and in aeronautic components. The heat protection element deposited on the substrate consists essentially of a quasicrystalline aluminum alloy consisting essentially of one or a number of quasicrystalline phases which are either a quasicrystalline phase in the strict sense or approximating phases. Such quasicrystalline aluminum alloy has one of the following general compositions: Al a Cu b Fe c X d J e I g , Al a Pd b Mn c X d J e T f , I g , Al a Cu b Co c X d J e T f I g , or Al a X d J e I g . | 2 |
BACKGOUND OF THE INVENTION
The invention relates to a machine for producing welds in a thermoplastic web. Machines of this kind are generally used for producing bags from the separated ends of a tubular web of thermoplastic synthetic which is intermittently fed to the welding station, said ends of said tubular web being advanced past the welding station. A difference is hereby made between the so-called separation seam welding, in which the end marked off by the weld is at the same time separated from the web by said weld, and bottom welding, in which, simultaneously with the production of the weld, a cut is made which lies next to the weld. The web ends thus separated during welding then form the bags which are stacked after they emerge from the welding station and are then carried away, either manually or by machine.
In separation seam welding, a welding bar, movable upward and downward, acts in conjunction with a counter roll which forms a base for the web in the welding station. After each welding operation, after the front end of the web is separated, the leading edge of the web remaining in the welding station remains in contact with the counter roll until it is advanced during the succeeding feeding step. The leading edge of the web is warmed and softened during the welding. During stoppage, the softened leading edge may stick to the counter roll, thereby causing interruption of production until the adhesion is corrected.
In bottom welding, the weld is usually produced by an upper and lower welding jaw. Here, during the short interruption of the intermittent feed or during an interruption of the welding process for a longer pause, the leading edge of the web can become softened by proximity to the heated lower welding jaw and stick onto it. This interrupts production until cleared.
Through DT-AS 1942410, U.S. patent application filed Sep. 16, 1968, Ser. No. 760,048, a machine for separation seam welding is known in which, during the stoppage of the intermittently operating feed mechanism, the welding bar is adjustable in such a way that even when its upward and downward movement continues, it attains a position in which it can no longer touch the web. The web, now resting due to the standstill of the feed mechanism, is to be thus prevented from coming into contact with the still-operating welding bar, so that the welding bar is temporarily rendered inoperative without the whole machine having to be turned off.
However, when the interruption of the intermittent feed extends over several work cycles of the machine, the leading edge of the web is capable of adhering to the base, as described above, when operation of the feed mechanism is resumed. This is especially disadvantageous in the welding station which includes a lower welding jaw, for example, in a bottom weld machine.
It is an object of the invention to provide a machine for producing welds on a thermoplastic web, in which adhesion of the last welded leading edge of the web in the welding station during an interruption of the intermittent feed can be certainly avoided.
SUMMARY OF THE INVENTION
These and other objects are achieved in the apparatus in accordance with the invention. According to the present invention, the feed mechanism is mounted displaceable against the feeding direction from a first position into a second position. During normal pauses in intermittent feeding and/or longer interruption of the feed, the feed mechanism is shifted against its feeding direction into its second position which pulls the just welded leading edge of the web out of the welding station. This displacement of the feed mechanism can be done manually such as by a hand-operated lever which may also be coupled to the means for switching off the intermittently operating feed mechanism.
An automatic displacement drive can also be provided for shifting the feed mechanism.
In a preferred embodiment, the displacement drive is regulated by a control mechanism such that the feed mechanism is shifted into its second position immediately after the end of each welding and separation operation. The displacement drive shifts the feed mechanism into its second position at the end of each welding operation and shifts it back into its first position before the next welding operation begins. Thus, during each stoppage of the web in the regularly repeated interruptions of the intermittent feed, the leading edge of the web is pulled out of the area of the welding station after the welding operation and adhesion of the softened leading edge is thus avoided.
The control mechanism may optionally be arranged to pull the leading edge of the web back from the welding station only or also during longer interruptions of the web feed. The welding operaion can thus be interrupted for as long as desired without the remainder of the operation of the machine having to be interrupted and having to render the welding apparatus inoperative. By permitting the welding apparatus to continue during the interruption, for example, the welding bar touches the counter roll in each work cycle. The counter roll is always kept at the same normal operating temperature as during welding. This permits resumption of welding without the faulty welds normally resulting while waiting for the counter roll to heat up to operating temperature. Known counter rolls consist of heat-resistant material, such as a silicone rubber layer coated with teflon-reinforced glass fiber, and are not damaged by regular contact with the welding bar.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described in detail in the following specification of two embodiments shown schematically greatly simplified in the drawings.
FIG. 1 is a perspective view of the welding station and of the feed mechanism of a first embodiment of the invention partly cut away.
FIG. 2 is a side view of the embodiment according to FIG. 1.
FIGS. 3 and 4 are side views corresponding to FIG. 2, of a second and a third embodiment, respectively, of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The embodiment, represented in FIGS. 1 and 2, of a machine for producing welds on a thermoplastic web 10, has an intermittently operating feed mechanism comprising two feed rolls 11 and 12 which rotate in the directions of the arrow, as shown, and thus advance the web 10 in the feeding direction 13, indicated by an arrow, and guide it into the welding station shown generally at 14. The web is guided into the gap between the feed rolls 11 and 12.
Feed rolls 11 and 12 are rotatably mounted with their ends in two levers 15 and 16, and are rotatably connected to each other through gears 17. Thus, when the lower feed roll 11 is rotated in the rotating direction, the upper feed roll 12 rotates simultaneously in the opposite direction. Levers 15 and 16 are rigidly joined to each other at their lower ends by a tube 18. A shaft 19, rotatably mounted in side walls 21 and 22 of the machine frame, runs through the tube 18. The levers 15 and 16 thus are permitted to swivel on the shaft 19 as a swivel axle, between the first position shown in FIGS. 1 and 2 in continuous lines, and into the second position shown in FIG. 2 in dotted lines. The first and second positions of the levers 15 and 16 are defined by abutment with stops 23 and 24, respectively, (FIG 2). Stop 24 consists of an adjustable screw which can be fastened with a lock nut to adjust the second position of the levers 15 and 16.
A sprocket pulley 25 is fastened to the shaft 19 inside the side wall 21, and another sprocket pulley 26 is fastened to the shaft 19 outside the side wall 21. The sprocket pulley 25 is connected by a sprocket belt 27 to a shaft 31, said shaft 31 being driven alternatively in opposite rotating directions, in the known way, through a brake-clutch combination 28, 29. The sprocket pulley 25 is therefore similarly intermittently rotated through appropriate regulation of the brake 28 and the clutch 29. The sprocket pulley 26 is connected by a sprocket belt 32 to a sprocket pulley 33 which is mounted on a shaft 34 on which also the lower feed roll 11 is mounted. A pneumatic stroke cylinder 35 with a piston 36 is provided as a displacement drive for swivelling both levers 15 and 16 and thus for adjusting the feed mechansim comprising the feed rolls 11 and 12 from the first into the second position, and back. A second stroke cylinder (not shown) may be disposed outside the side wall 22. The stroke cylinder 35 is mounted on the side wall 21, swivelling on an axle 37. Its piston rod 38 is swivelably connected to the lever 15 through a joint 39.
The welding station 14 has a welding bar 41 extending horizontally and transverse to the feeding direction 13. The welding bar, during stoppage of the web, is movable by a drive, not shown, from the raised resting position shown into a welding position pressing against a counter roll 42. When touching the web 10 introduced into the welding station 14, the welding bar 41 separates the end 43 of the web 10 projecting over the said welding bar 41 and said end of the web is carried away by a conveyor mechanism 44.
The upward and downward movement of the welding bar 41 is produced in the known way such as by continuously rotating cam discs or a crank mechanism or intermittently operating electrical or fluid actuating means. The intermittent drive for the feed rolls 11 and 12, adapted to this upward and downward movement of the welding bar, is caused by a corresponding regulation of the brake 28 and the clutch 29, as indicated above. For this a control device 45 of any type known in the art is actuated by rotating cams or other means. The rotating cams may be rotated by the common drive of the machine, which also drives the welding bar upward and downward. This kind of control is generally known so that a detailed description is superfluous.
The supply and discharge of compressed air on both sides of the double acting piston 36 of the stroke cylinder 35 takes place through pipes 46. The pipes 46 are connected through a valve 47 to an opening, not shown, for supply or exhausting compressed air. The valve is also controlled by the control device 45. The welding operation may be stopped while the welding device continues to run without melting the leading edge of the web. This is accomplished in the embodiment represented in FIGS. 1 and 2 by the control device 45 actuating the stroke cylinder as a welding operation is completed and the welding bar 41 starts to raise from the web 10. The feed rolls 11 and 12 are stopped at this time and the stroke cylinder 35 moves the feed rolls 11, 12 from the first position into a second position, shown in FIG. 2. In the second position, the leading edge of the web 10 is withdrawn from the welding station 14 and lies on a base 48 which is not heated during welding. The welding bar 41, continuing to move up and down, now directly touches the counter roll 42 without touching the leading edge of the web 10. The continued periodic contact between the welding bar and the counter roll at the normal cyclic rate maintains the counter roll near its usual production temperature. Welding can therefore be resumed at will wlthout waiting for the counter roll to heat up.
When welding is to be resumed, the drive of the feed rolls 11 and 12 is switched on and stroke cylinder 35 is actuated at the proper time by control device 45 so that the normal welding operation can begin again.
In the embodiment represented in FIG. 3, all the parts which essentially correspond to the embodiment in accordance with FIGS. 1 and 2, have the same reference numbers so that through this indication, the preceding description can be referred to.
The embodiment in accordance with FIG. 3 differs from the preceding embodiment principally in that this embodiment involves bottom weld machines in which the weld is produced by an upper welding jaw 141 and a lower welding jaw 142, without at the same time cutting the web at the weld. A cutting apparatus is provided for separating the one end 43 of the web 10 which forms a bag. The cutting apparatus has upper and lower blades 51 and 52, respectively. The upper blade 51 is moved up and down together with the upper welding jaw 141. In other respects, the set up and the function of the machine shown in FIG. 3 is the same as in the machine shown in FIGS. 1 and 2.
The embodiment shown in FIG. 4 differs from the preceding embodiment in that here, instead of using a stroke cylinder 35 for displacement of the feed mechanism 11, 12, a cam disc 53 is provided which engages one or both levers 15 or 16. This cam disc 53 moves the feed mechanism 11, 12 against the strength of a spring 54 at regular intervals from the first position into the second position and then controls its return movement through the strength of the spring 54. The shaft 55 carrying the cam disc 53 is rotated synchronously with the drive shaft for the welding mechanism, so that through appropriate shaping of the cam disc 53, the control realized by the said cam disc at the same time forms the displacement drive which shifts the feed mechanism 11, 12 into its second position immediately after the end of a welding and separating operation and causes the spring 54 to shift the feed mechanism 11, 12 back to its first position promptly before the next welding operation. In this embodiment, therefore, the control of the displacement drive is released by each welding operation.
A bolt 56 interferes with the return of the feed mechanism 11, 12 during a longer interruption of the welding process while the welding mechanism continues to run. This pulls back the leading edge of the web from the welding station and keeps it in this position for the duration of the stoppage of the welding operation. The bolt 56 may be automatically moved by the control mechanism 45 into the path of the lever 15 when the lever is in the second position and the intermittent drive of the feed rolls 11, 12 has been stopped. When the welding process is resumed, the bolt 56 is moved by the control mechanism 45 out of the path of the lever 15 so that the above-described continuous operation can take place again. Manual operation of the bolt 56 may also be employed.
For simplification of the description, only one cam disc 53 and one stroke cylinder 35 for interaction with the lever 15 are mentioned above. It is within the contemplation of the present invention that each of levers 15 and 16 be provided with one cam disc 53, stroke cylinder 35 or bolt 56 each.
In the foregoing, the invention was described on the basis of embodiments in which feed rolls 11 and 12 are provided for the intermittent feed of the web 10. Instead of the feed rolls 11 and 12, any other kind of feed mechanism suitable for an intermittent feed of a web can be provided.
In the embodiments in accordance with FIGS. 1, 2 and 4, in order to prevent the counter roll 42 from being unequally warmed by the contact with the welding bar 41 and at the same time to hasten the separation of the end 43 from the web 10 in separation seam welding, in both the cases mentioned, the counter roll 42 is driven at a slightly greater peripheral speed than the feed rolls 11 and 12.
It will be understood that the claims are intended to cover all changes and modifications of the preferred embodiments of the invention, herein chosen for the purpose of illustration which do not constitute departures from the spirit and scope of the invention. | A displacement device in a thermoplastic web welding apparatus withdraws the leading edge of the web from the welding apparatus during pauses in feeding and/or production to prevent melting and sticking of the leading edge. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a route-inquiry method, and more particularly, to a route-inquiry method which generates a plurality of feasible routes according to a source and a destination.
[0003] 2. Description of the Prior Art
[0004] Please refer to FIG. 1 . FIG. 1 is a flowchart illustrating a prior art route-inquiry method 100 . The method 100 is performed as follows:
[0005] Step 110 : Start;
[0006] Step 120 : Input a source and a destination;
[0007] Step 130 : Generating a route according to the source and the destination;
[0008] Step 140 : Display the route;
[0009] Step 150 : End.
[0010] Generally, the route generated in step 130 is considered with the traveling distance, that is, if a user wants to travel to the destination from the source, the method 100 will generate a route with the shortest distance. However, if the user wishes to find a route with other preferences such as the shortest time, the method 100 is unable to find a corresponding route to satisfy the user's request.
SUMMARY OF THE INVENTION
[0011] The present invention provides a route-inquiry method comprising generating a plurality of feasible routes according to a source and a destination.
[0012] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a flowchart illustrating a prior art route-inquiry method.
[0014] FIG. 2 is a flowchart illustrating a route-inquiry method according to the present invention.
[0015] FIG. 3 is a diagram illustrating indication of a plurality of routes in a map mode.
[0016] FIG. 4 is a diagram illustrating indication of the plurality of routes in FIG. 3 in a pathway mode.
[0017] FIG. 5 is a diagram illustrating indication of the plurality of routes in FIG. 3 in a parameter mode.
[0018] FIG. 6 is a block diagram illustrating a route-inquiry device according to the present invention.
DETAILED DESCRIPTION
[0019] Please refer to FIG. 2 . FIG. 2 is a flowchart illustrating a route-inquiry method 200 according to the present invention. The method 200 comprises the following steps:
[0020] Step 210 : Start;
[0021] Step 220 : Input a source, a destination, and optional preferences, then go to step 240 ; if only a destination is input, then go to the step 230 ;
[0022] Step 230 : Detect the source;
[0023] Step 240 : Generate a plurality of routes according to the source, the destination, and optional preferences;
[0024] Step 250 : Input a mode selection;
[0025] Step 260 : Display the plurality of routes according to the mode selection;
[0026] Step 270 : End.
[0027] In step 220 , a user does not have to enter the source. Instead, the route-inquiry method 200 provides the step 230 to detect the source. If the user does not enter the source, the step 230 detects the position of the user and uses the position of the user as the source. The position of the user can be detected by a Global Positioning System (GPS).
[0028] In step 240 , a plurality of routes are generated, which provides the user many traveling choices. The optional preferences can include estimated traveling time, preferred roads, road condition, etc. For example, if the optional preference of shorter estimated traveling time is selected, then step 240 will generate a plurality of routes with shorter estimated traveling times. If the optional preference of preferred roads is selected, the step 240 will generate a plurality of routes each of which includes the preferred roads. If the optional preference of road condition is selected, the step 240 will generate a plurality of routes which avoid roads with traffic jam and roads under construction, etc. Further, the method 200 allows the user to select more than one optional preference. For example, the user can select the optional preferences of shorter estimated traveling time and preferred roads at the same time. In that case, step 240 will generate a plurality of routes with shorter estimated traveling times and include the preferred roads. Further if no optional preferences are selected, then step 240 will generate a plurality of routes with a predetermined preference.
[0029] In step 250 , the user can choose to select a display mode. The display mode can be a map mode, a pathway mode, a parameter mode, etc. Then in step 260 , the plurality of routes are displayed according to the selected mode. If the map mode is selected, the plurality of routes generated in step 240 will be highlighted on a map with different routes highlighted in different manners such as different colors, line shapes, etc. If the pathway mode is selected, the names of pathways along each of the routes generated in step 240 will be displayed in sequence to indicate the route. If the parameter mode is selected, certain parameters such as time, distance, etc. of the plurality of routes generated in step 240 will be displayed. The combination of different modes allows the user to choose an optimal route more appropriately. If none of the modes are selected, then the plurality of routes will be displayed according to a predetermined mode.
[0030] Please refer to FIG. 3 . FIG. 3 is a diagram illustrating indication of a plurality of routes R 1 -R 4 generated in step 240 in the map mode. As shown in FIG. 3 , the source is A, the destination is B, and routes R 1 -R 4 are displayed in the map with different symbolic lines. Moreover, the symbolic lines can be assigned with different meanings. For example, a dashed line as shown in route R 2 can be used to indicate that it is the route with the shortest estimated traveling time. In this case, the map mode provides the user information not only routes R 1 -R 4 on the map, but information regarding to estimated traveling time. Furthermore, when the user makes a request to display only the route which is chosen, all other routes will disappear from the map.
[0031] Please refer to FIG. 4 . FIG. 4 is a diagram illustrating indication of routes R 1 -R 4 in the pathway mode. As shown in FIG. 4 , routes R 1 -R 4 are displayed by names of pathways along each of routes R 1 -R 4 . For instance, route R 1 starts at road 1 , passes through road 2 , and finishes at road 3 . The display of routes R 1 -R 4 can be sorted by different preferences. For example, if the preference of distance is selected, then route R 1 will remain on the top list, followed by route R 3 , R 2 , and R 4 referencing to FIG. 3 .
[0032] Please refer to FIG. 5 . FIG. 5 is a diagram illustrating indication of routes R 1 -R 4 in the parameter mode. As shown in FIG. 5 , certain parameters such as estimated traveling time and distance of routes R 1 -R 4 are displayed. For example, route R 2 has the estimated traveling time of 1.5 hours, and the distance of 60 kilometers. If the user wants to select a route with more freeways, the user may choose route R 4 although it has a longer distance than some other routes.
[0033] Please refer to FIG. 6 . FIG. 6 is a block diagram illustrating a route-inquiry device 600 of the present invention. As shown in FIG. 6 , the route-inquiry device 600 includes an interface 610 , a central processing unit(CPU) 620 , a database 630 , and a display 640 . The interface 610 is for the user to input information such as the source, the destination and preferences. The database 630 is disposed for storing data such as different pathways. The central processing unit 620 is used to search and generate different routes for the user according to input data. The display 640 is used to display different routes generated by the central processing unit 620 .
[0034] The route-inquiry device and method of the present invention provide the user many different kinds of information regarding different routes. Therefore, the user is able to choose an optimal route perceived by the user from a plurality of routes.
[0035] Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. | After a user inputs a source, a destination and preferences, many different routes will be generated accordingly. Some of the routes may have shorter estimated traveling times, some of the routes may have shorter traveling distances, but other routes may make use of freeways. Different kinds of routes can be indicated simultaneously and thus the user can choose an optimal route perceived by the user from the generated routes. | 6 |
This is a continuation application of prior application Ser. No. 08/094,621, filed on Jul. 20, 1993, which is a continuation of Ser. No. 07/747,496, filed Aug. 19, 1991, which was a continuation of Ser. No. 534,196 filed Jun. 5, 1990, now abandoned, which was a continuation of Ser. No. 07/081,989, filed Aug. 4, 1987.
BACKGROUND
FIELD OF THE INVENTION
The field of the invention is plant genetics, including genetic mapping and restriction fragment length polymorphism technology.
DESCRIPTION OF RELATED ART AND INTRODUCTION TO THE INVENTION
When considering the application of biotechnology to plant improvement, a great deal of emphasis is usually placed on the strategy of introducing novel variability into plants via genetic engineering techniques. Over the past decade, advances have been made in developing methods of transferring genes to plant cells (see Potrykus et al., Plant Mol. Bio. Rep. 3:117-128 (1985)). For example, transfer and expression of single genes improving insect and herbicide resistance has reportedly been achieved in plants (Abel et al., Science 232:738-743 (1986); Shah et al., Science 233:478-481 (1986)). While there is excitement over advances in plant genetic engineering, the prospects for the general use of these techniques for plant improvement are tempered by the realization that very few genes corresponding to plant traits of interest have been identified or cloned.
One procedure that has been used by plant breeders to increase efficiency in the testing of traits which are difficult or expensive to evaluate is the use of indirect selection criteria (Hallaver and Miranda, Quantitative Genetics in Corn Breeding (Iowa State University Press 1981). One indirect selection criterion, for example, might be an easily recognized morphological characteristic of the plant which is either genetically linked to the desired trait or perhaps a component of the desired trait, e.g., the association between leaf size and seed size in beans.
Agronomically important traits such as, for example, plant yield, height, maturity, and fruit and grain characteristics, are all attractive targets for manipulation in plant improvement programs, but often have very low heritabilities. Heritability is the ratio of genetic to total variation and, therefore, is important to the efficiency of the selection process. Influencing heritability of such traits, sometimes termed "quantitative" traits, is difficult, however, because expression of a number of different gene products generally influences the phenotype. Quantitative traits are characterized by continuous rather than discreet distribution of phenotypic expression. There is currently a poor understanding of how single genes influence the expression of complex traits and, in conventional plant breeding programs, selection for inheritance of quantitative traits is difficult due to the unrecognized genetic basis of the trait. The use of direct gene transfer in manipulating these traits, of course, is therefore difficult due to problems in pinpointing and then cloning those individual loci which contribute predominantly to the expression of the trait. Determination of genotypic information from phenotypic values is further imprecise because evaluation of the trait may frequently be confounded by environmental effects (Berger, "Multiple-Trait Selection Experiments: Current Status, Problem Areas and Experimental Approaches." In: Proceedings of the International Conference on Quantitative Genetics (Pollack et al., Eds.), p. 191-204 (Iowa St. Press 1977)).
Clearly, one area in which biotechnology may have a significant impact on plant improvement is in the development of new methods to identify and characterize the role of individual plant genes in quantitative trait expression. Following the development of a new class of plant molecular markers based on restriction fragment length polymorphisms, termed "RFLPs", (Helentjaris et al., Plant Mol. Bio. 5:109-118 (1985)) ("Helentjaris et al. I"), the processes to identify such loci and discriminate gene effects have been invented and are described and claimed herein. This and all other publications noted herein are hereby incorporated by reference. This will undoubtedly benefit plant improvement, not only within the context of conventional breeding approaches, but also by providing a means for identifying appropriate loci for future cloning and direct gene transfer efforts.
RFLPs are differences observed between genotypes in the fragment lengths of restriction endonuclease-digested DNA. RFLPs occur as a result of base pair or positional changes in the restriction enzyme recognition sites which flank a chromosomal location and can be detected by hybridization of labelled DNA clones containing sequences that are homologous to a portion of the chromosomal fragment. Hybridization with a unique cloned sequence can permit the identification of a specific chromosomal region (locus).
This technology employs cloned DNA fragments to detect differences between individuals at the DNA sequence level. When genomic DNAs from two genetically distinct individuals are digested with a restriction enzyme, electrophoresed and probed with a labelled DNA clone, polymorphisms in the hybridization patterns sometimes result due to sequence differences between the individuals. The term "restriction fragment length polymorphism" has been coined to describe this variation.
Differences in fragment lengths which are revealed, for example, by agarose gel electophoresis, function as alleles of that RFLP. Thus, RFLPs can serve as genetic markers in a manner analogous to conventional morphological or isozyme markers. Unlike most genetic markers, however, they are not the products of transcription and translation. Additionally, RFLP possess certain additional advantages over previously available genetic markers. First, RFLPs reflect existing differences between genetically distinct individuals. The potential number of RFLPs for all practical purposes is thus unlimited, as digestion of the genomic DNA of any higher eukaryote with a six base recognition enzyme will generate more than a million fragments, many of which can be polymorphic. Additionally, over one hundred different restriction enzymes have now been described, each of which may generate a new and different set of fragments (Roberts, Nuc. Acids Res. 10:117-144 (1982)). The utility of isozyme markers or morphological markers in studies is frequently limited by a lack of informativeness in lines of interest or by an insufficient availability or chromosomal distribution of the loci.
The use of isozyme variation in plant breeding is, like RFLP technology, one of indirect selection. (Tanskley and Orton, Isozymes in Plant Genetics and Breeding 1B (Elsevier, N.Y. 1983). The time required to backcross a trait from a donor to a recurrent parent is the product of the generation time by the number of generations. Therefore, screening for traits linked to isozymes, which may sometimes be identified in seeds or seedlings, can reduce the time required for evaluation, especially if the expression of that trait is controlled by recessive alleles. In addition, the number of backcross generations necessary to sufficiently recover the phenotype of the recurrent parent can be reduced by selection for isozymes associated with the recurrent parent.
In tomato, closely linked isozyme variation has been used to follow the inheritance of several simply inherited traits such as, for example, nematode resistance (Rick and Fobes, Rep. Tomato Genet. Coop. 24:25 (1974)). The inheritance of quantitative traits has also been followed by the use of multiple isozyme loci. For example, in tomato, eleven isozyme loci were used to survey eight of the 12 chromosomes and three independent genetic factors were detected in association with cold tolerance (Vallejos and Tanksley, Theor. Appl. Genet. 66:241-247 (1983)). In maize, changes in the frequency of eight isozyme loci were found to be associated with selection for improved grain yield (Stuber et al., Crop. Sci. 22:737-740 (1982)). Nevertheless, for a multigenic trait, only that portion of the genome closely linked to an isozyme marker can be considered, and many other major or minor genes may be associated with the expression of quantitative traits.
Maize is perhaps the best characterized plant system in terms of isozymes and yet only about two dozen isozyme loci have been located and it is rare for more than a dozen of these to be informative in any particular cross involving Corn Belt germplasm. By contrast, using the inventors' RFLP technology, over 300 RFLPs covering all ten maize chromosomes have been characterized (Helentjaris et al., Trends in Genetics. 3:217-221 (1987)). The level of informativeness of these RFLPs is great. In a study involving the maize cross Tx303×Co159, only 13 informative isozyme loci with very biased coverage of less than the 10 chromosomes were available. In contrast, using RFLP analysis, more than 99 informative RFLPs covering all 10 chromosomes can be analyzed in the same cross (unpublished data). In a recent comparative survey of Corn Belt germplasm RFLPs averaged greater than five alleles per locus while isozyme loci averaged less than two (M. Walton and T. Helentjaris, abstract).
RFLP markers rarely possess detectable phenotype effects of their own, so they can be utilized in economic lines without detriment and many can be evaluated at one time without the pleiotropic effects often seen with phenotypic markers. Evaluation can be performed on small amounts of DNA obtained from plant tissue at virtually any stage of plant development from roots, to shoots, to fruits, or even with tissue culture material. Evaluation of RFLPs is not affected by environmental factors and greenhouse-grown plants will not differ from field-grown plants when tested. Finally, the evaluation of RFLPs reveals the exact genotype, so the heterozygous state can be differentiated from the homozygous condition at any chromosomal location.
Many of the potential applications and theoretical advantages of RFLPs compared to more conventional phenotypic or isozyme marking systems have been described previously. Helentjaris et al. I. In one application of the use of RFLP markers in plant studies, genetic linkage maps based on these markers have been constructed for both maize and tomato (Helentjaris et al., Theor. Appl. Genet. 72:761-769 (1986)) ("Helentjaris et al. II"). Similar linkage maps are also being constructed for other crop species, such as Brassica Figdore et al., Theor. Appl. Genetics. 75:833-840 (1988); Slocum et al., In "Genetic Maps" (S. J. O'Brien, ed.), 5th Edition, Cold Spring Harbor Press, N.Y. (1990)). Close to 120 RFLPs in tomato have been arranged into linkage groups by comparing segregation patterns in an F2 population derived from homozygous parental lines. Approximately 70 RFLPs have been mapped by another group of workers. Bernatzky and Tanksley, Genetics 112:887-898 (1986). Over 300 RFLPs in maize have been arranged into linkage groups (Helentjaris et al., 1986; Helentjaris et al., 1987). The locations of the maize RFLP loci have been correlated to the conventional maize genetic map by analyzing the inheritance patterns of the RFLPs in maize lines monosomic for different chromosomes (Helentjaris et al., Proc. Nat. Acad. Sci. USA 83:6035-6039 (1986)) ("Helentjaris et al. III"), by establishing linkage relationships with isozyme markers, cloned genes, and morphological markers with previously identified chromosomal locations (Wright et al., MNL 61:89-90 (1987)), and by analyzing inheritance patterns in B-A translocation stocks (Helentjaris et al., Weber and Helentjaris, Genetics 121:583-590 (1989). The resulting map (FIG. 1) shows the resolution possible.
Numerous direct applications of RFLP technology to facilitate plant breeding programs have been suggested. Helentjaris et al. I. Because of the large numbers of RFLP markers available in a population of interest, one of the more important applications of RFLPs may be as markers linked to genes affecting the expression of quantitatively inherited traits. In this application, RFLPs function as indirect selection criteria for traits which are difficult or expensive to evaluate phenotypically. A prerequisite for the use of RFLPs as indirect selection criteria is the identification of RFLPs closely linked to the quantitative trait loci (QTL) affecting expression of the trait of interest.
Currently, the introgression of quantitative traits from one germplasm to another involves the identification of favorable genotypes in segregating generations followed by repeated backcrossing to commercially acceptable cultivars. This procedure is feasible for simply inherited quantitative traits, but as the number of genes controlling a trait increases, screening the number of F2 segregants required to identify at least one individual which represents the ideal (homozygous) genotype quickly becomes prohibitive. For example, with one gene and two alleles of equal frequency, the probability of recovering a desirable genotype in the F2 generation is 1/4. However, if the number of genes is increased to 5 or 10, the probability of recovering an ideal genotype in the F2 population is reduced to approximately one in one thousand and one in one million, respectively. Thus, to identify desirable segregants, one must either reduce the number of segregants needed or have available very efficient screening procedures. Additionally, in situations where enviromental effects interfere with the ability to draw accurate genotypic information from the phenotype, large allocations of time and resources are required to evaluate progeny in replicated trials within several target environments.
Described and claimed herein is the use of RFLPs to dissect multigenic traits into their individual genetic components. A genome, or portion thereof, saturated with RFLPs or probed with select RFLP markers, all of which can be evaluated together in individual plants, has been found to give the resolution necessary to break down traits of complex inheritance into individual loci, even those under a significant environmental influence. The procedure is equally workable with dominant or recessive traits and can be used to accelerate introgression of desired genes into a commercially acceptable cultivar. As used herein, "plants" includes all forms of plant life, such as crop plants, mushrooms and fungi, ferns, trees, flowers and so on. These examples are not intended to be limiting but are merely illustrative of the wide applications of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A shows the regression between genotypes at RFLP locus "A" and plant height, identifying an additive gene.
FIG. 1B is a graphical depiction of the relationship between genotypes at RFLP locus "B" and plant height when the locus is not associated with plant height.
FIG. 1C shows the relationship between genotypes at RFLP locus "C" and plant height, identifying a non-additive gene.
FIG. 2 illustrates the correlation between colorimetric absorbance values (2TD) and various RFLP loci on three linkage groups. Numbers in parentheses refer to correlation coefficients, numbers above lines indicate locus identification, and numbers below lines indicate recombination fractions (experiment 1).
FIG. 3 shows the distribution of colorimetric absorbance values (2TD) for an F 2 population derived from a cross between P.I. 134417 and Manapal (experiment 2).
FIG. 4 portrays the observed versus predicted values for colorimetric absorbance (2TD).
FIG. 5 is a plot of residual versus observed colorimetric absorbance values (2TD).
FIG. 6 is a representations of a tomato genetic linkage map of RFLP loci; circled loci are those screened for association with expression of water-use efficiency.
FIG. 7 shows the correlation between observed water-use efficiency versus predicted water-use efficiency based on a multiple regression model.
FIG. 8 is a plot of observed water-use efficiency versus residuals from a multiple regression model.
FIG. 9 shows RFLP loci that were found to be associated with the expression of soluble solids (circled).
FIG. 10 displays the correlation between observed versus expected expression of soluble solids.
FIG. 11 is a plot of residuals from a regression model versus observed soluble solids.
FIG. 12 shows RFLP loci that were found to be associated with the expression of tomato fruit weight (circled).
FIG. 13 illustrates the correlation between observed versus expected expression of tomato fruit weight.
FIG. 14 shows the correlation between residuals from a regression model versus observed values of tomato fruit weight.
FIG. 15 is a representation of RFLP loci that were found to be associated with the expression of soluble solids in California and Chile and fruit weight (circled).
DETAILED DESCRIPTION OF THE INVENTION
The invention typically involves genetic linkage maps constructed with RFLP technology and the use of RFLP probes to correlate those probes with Quantitative Trait Loci (QTL) and the degree of inheritance of particular multigenic traits.
In one embodiment, a plant source (designated P 1 ) having a desired multigenic trait--for example, increased height--is recovered and crossed with a second plant (designated P 2 ) having essentially or substantially opposite characteristics, that is, decreased height. Heterozygote plants from the F 1 population are selfed to create a segregating (F 2 ) plant population which exhibit a gradient with respect to height, i.e., with respect to the degree of expression of the multigenic or quantitative trait of interest.
Quantitative values for the trait of interest (height) are determined and assigned to each individual parent plant, F 1 population plant, and F 2 segregation plant and a genomic DNA sample from each plant is prepared for Southern blotting. Following preparation for a Southern blot--which may be constructed to contain, for example, DNA from 25 to 50 or more different F 2 plants--an RFLP probe is randomly chosen or selected from an RFLP genetic linkage map and hybridized to create the blot. Additional Southern blots are constructed using other RFLP probes. As indicated above, the RFLPs to be used for this purpose, i.e., the indirect selection of a QTL, may but need not be randomly chosen. They can be selected in systematic fashion from the RFLP genetic linkage map. For example, for a trait of completely unknown location, several spaced RFLPs from each of the 10 chromosomes of maize may be selected for Southern blot testing for the location of DNA associated with a desired height. Alternatively, of course, all mapped RFLPs may be used.
Following these Southern blot constructs, a matrix may be prepared having an identification of each plant that has been tested, followed by its quantitative trait measurement (height) and the genotype as revealed by each RFLP probe tested. Typically, only three genotypes will be seen: P 1 , P 2 and F 1 , the latter being heterozygous and having one chromosome from each parent. Thus, from the matrix all plants can be grouped into one of three RFLP genotypic categories: P 1 P 1 , P 1 P 2 or P 2 P 2 . If, with one or more RFLPs, the so-grouped plants, when averaged, all show approximately equal expression of the trait of interest, i.e., the average height of plants in all groups is about the same, that RFLP is deemed noninformative. In other words, there was no association between the trait of interest and that particular RFLP or RFLPs. The genotype of the plant at the location of the RFLP was not relevant to the trait of interest.
Another RFLP, however, may show association with height. For example, the average height of the maize plants, respectively, in each of the P 1 P 1 , P 1 P 2 and P 2 P 2 groups for a different RFLP, respectively, may be 3 feet, 4 feet and 5 feet. With this information, it may be presumed that this RFLP, as revealed by the degree of its correlation to the P 2 P 2 genotype, hybridizes to maize DNA in the area of a gene for height.
In the above-described manner, it is possible to review results from a first group of RFLP probes used to screen for association to the trait of interest. Use of an RFLP genetic linkage map allows the selection of further RFLPs to be tested on an objective, rather than random, basis. Correlation may be improved by testing RFLPs located on either side of that RFLP or RFLPs which initially showed the strongest association. Once the best probe or probes are identified they may then be utilized, by way of example, in a breeding program to select plants having a desired height.
It is to be noted, of course, that in a multigenic system, there may be three, four, or more different genes contributing to one trait. In such a situation there may, therefore, be many different quantitative expressions of that trait and no one gene can account for, or be relied upon to predict, that expression. We have further determined that the relative importance of each correlating RFLP can be determined. Particular values can be assigned to those RFLPs and utilized in a mathematical model to assist in predicting the degree of trait expression in a particular plant.
The following is a hypothetical example of the analysis of RFLP data, and the development of a predictive model relative to identification, localization and introgression of a quantitative trait, plant height, assuming the possession of RFLP data on 3 loci. A matrix or table which includes the necessary raw data is presented in Table 1. In this hypothetical, plant height ranges from 0 to 100 units. The genotypic classes for 3 RFLP loci are also presented.
The first objective of the analysis to determine which, if any, of the 3 RFLPs are associated with the expression of plant height. To determine the relative importance of any individual RFLPs, a simple regression of plant height by genotypic value is used. This can be referred to as the average effect of an allelic substitution, as it enables observation of how the value of plant height changes as "A" alleles are substituted for "a" alleles. The regression for RFLP "A" is presented in FIG. 1a. Here we see that the average height of all plants which have a genotype of aa is approximately 12.5 units. Likewise, for Aa individuals, the average is approximately 62.5 units and, for AA individuals, the average expression of plant height is 100 units. The regression of plant height by the genotypic values provides a least squares regression line, which in this hypothetical has a slope of 45. "Least squares" refers to the fact that in this line the squares of the deviations of the points from the regression line are minimized, i.e., this line represents the "best fit" for the 5 points. The slope of the line can be interpreted as saying that each time an "A" allele is substituted for an "a" allele, plant height increased 45 units. The conclusion to be drawn from the regression of RFLP "A" is that it is strongly associated with the expression of plant height or that a gene(s) very closely linked to RFLP "A" is important in the expression of plant height.
In contrast, RFLP "B" is not associated with the expression of plant height (FIG. 1b). In this case, the average expression of plant height is 50 units regardless of the genotype of RFLP "B". Hence its regression line has a slope of 0 and the RFLP is deemed noninformative.
RFLP "C" (FIG. 1c) is similar to "A" in that plant height is clearly associated with the genotype. The slope of the line through the observed data points is not simply linear, however, but rather the "best fit" regression line is a curve (quadratic). The reason RFLP "C" is different from "A" is that "C" reflects a gene with dominance type gene action compared to the additive gene action of "A". RFLP "C" illustrates complete dominance, i.e., the average plant height of genotype Cc is essentially equivalent to that of the homozygote class CC. Thus, although RFLP "C" is not additive in gene action, it is still identified as being important in the expression of plant height.
These three hypothetical RFLPs illustrate the most common associations between RFLPs and traits of interest. It is to be emphasized that the resolution possible through RFLP analysis permits not only the identification of the RFLP associated with the expression of a trait, but also permits the identification of the type of gene action (additive or dominance). Thus, in this hypothetical, the conclusion is that of the three RFLP evaluated, "A" is important with additive gene action and "C" is important with dominance gene action. "B" was not associated with expression of plant height and would not be considered in further analysis.
Information similar to that obtained from the RFLP plots of plant height by genotypic classes can also be gleaned from an analysis of variance, such as that shown in Table 2. The objective of an analysis of variance is to partition the total phenotypic variance into specific sources. In this case, the logical question is to ask how much of the total variation for plant height can be attributed to differences among genotypes and how does the magnitude of that variance compare to the error (deviations from regression).
In the case of RFLP analysis, there are three different genotypic classes, i.e., AA, Aa and aa. Among three classes there are two possible contrasts and, hence, there are 2 degrees of freedom among genotypic classes. Moreover, the two possible contrasts among genotypes can be specifically partitioned into linear and quadratic sources, each with one degree of freedom. The linear contrast would have the values -1, 0 and +1 for the three genotypic classes AA, Aa and aa, respectively. This effectively compares the difference between the AA class and the aa class, i.e., the parental classes. The values for the quadratic contrast are 1, -2 and 1 for the three genotypic classes and, therefore, compare the difference between the mean of the parental AA and aa classes to the heterozygote class Aa.
The error, or deviation from regression, reflects the failure of the observed points to be exactly on the regression line. In the case of RFLP "A" we can observe that the mean square for the linear contrast is approximately 100 times larger that of the quadratic contrast and about 10 times larger than the error mean square. The magnitudes of the mean squares from the analysis of variance indicates that linear regression can account for the majority of the variance among the plant heights. The r 2 (coefficient of determination) value can be defined as the sums of the linear and quadratic mean squares divided by the total phenotypic variance (the total sums of squares of deviations from mean). The r 2 value for "A" indicates that 89% of the observed variance for plant height can be explained as due to differences among RFLP "A" genotypic classes. Similarly, the analysis of variance for RFLP "B" indicates that none of the variance for plant height can be explained due to differences among genotypic classes. The analysis of variance for RFLP "C" indicates that 53% of the variance can be explained due to differences among genotypic classes and that both the linear and quadratic contrast are important. Thus, the relative magnitudes of mean squares from the analysis of variance provides a description of the relationship between RFLPs and plant height. The conclusions coincide with those obtained from observation of the plots of plant height by genotypic classes shown in FIG. 1.
The means for each genotypic class are also presented in Table 2. These means represent the average phenotypic performance for each of the 3 genotypic classes. For RFLP "A", the mean of the parent 1 class (aa) is 12.5, the mean for the heterozygous class (Aa) is 62.5, and the mean for the homozygous parent 2 class (AA) is 100 plant height units. The linear regression line slope (b1) is also presented for each RFLP. Thus, the linear regression of plant height on genotypic classes for RFLP "A" is 45. This, as noted above, can be interpreted as indicating that each time an "A" allele is substituted for an a allele that plant height will increase 45 units. The slope thus permits comparisons among RFLPs and helps to identify those RFLPs most strongly associated with the expression of a trait of interest.
Once the RFLPs most strongly associated with the expression of a trait are identified, the effects of each RFLP may be combined into a multiple regression model which will permit prediction of expression of the trait of interest based on knowledge of the genotypes of specific RFLP. The effects of each RFLP are not strictly additive because the effects of RFLP may be correlated. For example, in this case, RFLP "A" and "C" may each provide some unique information, but part of the information provided by one RFLP may also be provided by another. Thus, the average effects of allelic substitutions may not be simply added together to provide a predictive model.
The general form of a useful multiple regression predictive model is shown below:
y=μ+b.sub.1 (genotype of RFLP locus 1)+b.sub.2 (genotype of RFLP locus 2)
where y is the predicted expression of a trait, μ s the weighted mean expression of the trait for the population, b 1 is the coefficient associated with a specific RFLP and so on. The genotype of a RFLP will be -1, 0 or 1 for genotypic classes AA, Aa and aa if the RFLP is additive (linear), or 1, -2 or 1 if the RFLP is quadratic (non-additive).
Determination of the "best" multiple regression model requires an interative process of substitution of RFLPs into and out of the model and the evaluation of interaction (epistatic) effects of RFLPs. For example, if two independent genes act together to provide expression of a trait, the genotypic class may involve the products of linear and/or quadratic genotypic values. The process for determination of the "best" multiple regression model can be done using stepwise regression procedures or by comparison of partial and sequential sums of squares from the regression models.
For example, in the present hypothetical, the logical RFLPs to include in the model would be the linear contrast for RFLP "A" and both the linear and quadratic contrasts for RFLP "C". The partial and sequential sums of squares (SS) for a model including RFLP A and C are the following:
______________________________________Source sequential SS partial SS______________________________________linear "A" 5580 2812linear "C" 62 236quadratic "C" 503 503______________________________________
The magnitudes of the sums of squares indicates that linear "A" is the most important determinate in explaining the variance for plant height. However, the reduction in partial SS (2812) vs. sequential SS (5580) for linear "A" suggests that much of the effect of linear "A" is accounted for by the linear and quadratic effects of "C". It should be noted that if the effects of each locus were completely independent there would be no differences in the partial and sequential sums of squares. Changes in the magnitudes of these sums of squares in an analysis of variance indicates that the effects of the different RFLP are correlated.
The iterative process of substituting linear and quadratic contrasts for different RFLPs can continue until a final predictive model is constructed. The objective of the model is to maximize the r 2 (coefficient of determination) value using as few RFLP as possible as predictive variables. The final model will generally eliminate RFLP which might flank a particular gene of interest because both RFLP will typically be contributing the same information. In addition, the final model might contain effects with reflect interactions between RFLPs.
In the present hypothetical, the next step in the process of model building might be to eliminate the linear contrast for RFLP "C". The results of this model are the following:
______________________________________Source sequential SS partial SS______________________________________linear "A" 5580 5127quadratic "C" 328 328______________________________________
The general agreement in magnitude between partial and sequential SS suggest that the effects of linear "A" and quadratic "C" are relatively independent. The r 2 value for this model is 0.95. Thus, 95% of the variance for plant height can be explained as due to differences among genotypic classes at RFLP "A" and "C". The final prediction equation would, therefore, be written as follows: ##EQU1## Thus, if the genotypes of RFLP A and C are known for a particular plant, the height of that plant can be predicted without having to measure its height following growth to maturity. In a breeding program, the breeder can analyze the genotypes of specific RFLP of seedling plants grown in a greenhouse during the winter and need only evaluate those plants predicted to have the desired plant height in the field the following summer.
TABLE 1__________________________________________________________________________Hypothetical Raw data "A" "B" "C"Genotype Observed (Linear Code) (Linear Code) (Linear Code) (Quadratic Code) Plant Height__________________________________________________________________________1 AA 1 bb -1 CC 1 1 1002 aa -1 bb -1 cc -1 1 03 Aa 0 BB 1 C c 0 -2754 Aa 0 Bb 0 CC 1 1 505 aa -1 BB 1 CC 1 1 25__________________________________________________________________________
TABLE 2______________________________________Analysis of Variance______________________________________ RFLP locus Degrees of A B CSource of Variance Freedom Mean Squares______________________________________Genotype 2linear 1 5104 0.0 2552quadratic 1 44 0.0 1575Error (deviations 2 625 6250 1458from regression)r.sup.2 0.89 0.0 0.53______________________________________Genotypes (code) Means______________________________________Homozygous (-1) 12.5 50 0Parent 1Heterozygote (0) 62.5 50 75Homozygous (+1) 100.0 50 58Parent 2Slope(b1) 45 0 23______________________________________
The breeding value of an RFLP as an indirect selection criteria is a function of the additive genetic correlation between the RFLP marker and a QTL. This genetic association is presumed to be due to linkage disequilibrium rather than due to pleiotropism. The problem of recombination between an RFLP and an associated QTL can be minimized if two RFLP are identified which flank the QTL. In that instance, the probability of a double crossover would be, assuming no interference, the product of their recombination frequencies. Nevertheless, localizing a target QTL between a pair of linked RFLP can be problematic, and the complexity of the analyses increased. One possible solution to the analysis using flanking RFLPs is to use multivariate analysis and derive one or more orthogonal vectors which include information from linked (correlated) RFLP loci. Alternatively, if crossovers are detected between the two flanking RFLPs for specific entries, the RFLPs linked to the QTL can be determined and information from the other RFLP discounted.
The rate of gain from indirect selection in a population is a function of the magnitude of the phenotypic variance of the desired trait, the selection differential, the heritability of the indirect criteria, and the genetic correlation between the direct and indirect criteria. Indirect selection for RFLPs will have an advantage over direct selection if the heritability of RFLPs is higher than the desired character and the additive genetic correlation between them is high.
The "heritability" of the RFLP phenotype is 1.0, i.e., genotype=phenotype. Hence, if the correlation between RFLPs and the desired trait is greater than the heritability of the desired trait, then RFLP-facilitated selection can be advantageous. In the evaluation of 2-tridecanone ("2TD")mediated insect resistance in tomatoes, for example, the development of the colorimetric assay has contributed to increased efficiency of selection. In the following Example 1, the correlation between observed and predicted colorimetric absorbance values of 2TD was 69% utilizing four correlating RFLPs. The magnitude of this correlation coefficient suggests that indirect selection for hirsutum alleles at the selected RFLPs will result in a correlated response towards increased colorimetric absorbance values. RFLP analysis can also provide a complete genotypic classification of individuals as seedlings in segregating generations, leading to especially useful information in a backcross breeding program, where superior genotypes can be identified prior to flowering.
As noted above, quantitative differences between genotypes are usually, but not always, influenced by genes at many loci, the effects of which are small in relation to the variation arising from other causes (Falconer, D.C., "Introduction to Quantitative Genetics" (2d Edition 1981)). Consequently, the individual genes involved in the expression of a quantitative trait are difficult to identify and Mendelian analysis cannot be applied. Id. Quantitative genetic analysis has therefore focused on estimation of breeding value which is the sum of the effects of the alleles at many loci. Nevertheless, a basic premise of quantitative genetics is that the laws which govern the inheritance of quantitative loci are the same as those which govern qualitative loci. The magnitude of the individual allelic effects which can be resolved through RFLP analysis will be a function of experimental error and recombination frequencies. As RFLP maps are developed which more completely saturate the genome, identification of more loci with smaller individual effects should be possible. Thus, RFLP analysis also offers the opportunity to determine the effects of individual loci (alleles) with major effects, and thereby to reduce the analysis of complex quantitative traits to classical Mendelian segregation ratios of individual alleles.
By way of example, field and laboratory determination of quantitative differences in insect resistance is often very expensive in terms of time and resources in most plant species, and genetic markers could greatly facilitate the determination of the breeding value of an individual genotype. In Example 1, noted above, 4 RFLPs on 3 linkage groups were found to be associated with expression of 2TD. In a previous study of an F 2 population derived from a cross between a L. hirsutum acession (LA 407) and an L. esculentum line (M82-1-8), 5 independent marker loci, 3 isozyme and 2 morphological, were found to be associated with expression of 2TD. Zamir et al., Euphytica 33:481-488 (1984). The morphological markers were the genes (sp) controlling determinant growth habit, and (sti) responsible for the presence of stipules at the base of the leaves, neither of which was segregating in the F 2 population evaluated in this study. If the 3 isozyme markers are polymorphic in the F 2 population used in this study and they are linked to the same QTL as the 3 RFLP, then isozyme markers could be used to predict 2TD. Nevertheless, because of the larger number of informative RFLPs available in population of interest, it is likely that an RFLP could be found more closely linked to a target QTL than isozyme or morphological markers. The results in Example 1 demonstrate that RFLPs can be used as indirect selection criteria to increase the frequency of favorable alleles associated with quantitatively inherited traits. In addition, other RFLPs not linked to a target QTL might also be used in a breeding program to select against the genotype of the donor parent. This combination of selection criteria applied in a backcross breeding program will facilitate the introgression of desirable genes and traits from wild relatives, and concurrently permit the rapid recovery of the genotype of the desirable recurrent parent.
The following Examples are set forth to assist in understanding the invention and should not, of course, be construed as specifically limiting the invention described and claimed herein. Such variations of the invention which would be within the purview of those in the art, including the substitution of all equivalents now known or later developed, are to be considered to fall within the scope of the invention as hereinafter claimed.
EXAMPLE I
The wild tomato L. hirsutum f. glabratum C. M. Mill P.I. 134417 (hirsutum) has been reported to be resistant to a wide range of arthropod pests of the cultivated tomato. The principal toxic factor has been identified as 2-tridecanone (2TD) which is localized in the tips of the glandular (type VI) trichomes which cover the foliage. In an analysis of an F 2 population derived from a cross between hirsutum P.I. 134417 and an L. esculentum (esculentum) cultivar "Manapal", it has been suggested that a minimum of 3 genes are involved in the inheritance of 2TD expression. Fery et al., Hort. Sci., 18:169 (1983). Moreover, in a cross between a L. hirsutum accession, LA 407, and a tomato breeding line, M82-1-8, 2 morphological markers and 3 isozyme loci were found to be associated with expression of 2TD. Zamir et al., supra.
The following procedures were designed to identify RFLPs associated with QTLs affecting expression of 2TD-mediated insect resistance. Additional objectives were to determine the gene effects of the RFLPs and to develop a predictive model for 2TD-mediated insect resistance using the 3 genotypic classes at each RFLP as predictor variables.
A tomato, Lycopersicon esculentum, L. cultivar, Manapal, and a selection from the non-domesticated tomato species L. hirsutum f. glabratum, P.I.134417, were obtained from Dr. George Kennedy, North Carolina State University, Raleigh. The F 1 hybrid was obtained using "Manapal" as the female parent. The F 1 was then self-pollinated to produce the F 2 seed used in all experiments.
In the first experiment, a group of test plants, which included parental, F 1 and a random sample of 100 different F 2 plants, were evaluated each month over a nine month period. All plants were grown in a greenhouse where temperatures were maintained between 15° and 25° C. and light intensity was supplemented to a minimum of 400 μmole photon m -2 s -1 for 18 hours per day. When the plants in each group developed at least 4 true leaves, 1 cm 2 leaf disks were sampled from 5 leaflets on each of the 3 largest leaves. The leaf disks were bulked and evaluated colorimetrically for 2-tridecanone (2TD) expression.
The colorimetric assay developed for 2-tridecanone is based upon the reaction of carbonyl groups in solution with 2,4-dinitrophenylhydrazine, which produces a wine red color in the presence of a base. Nienhuis, et al., Hort. Sci. (abstract) 20:590 (1985). In a population of 36 random F 2 plants derived from a cross between L. hirsutum f. glabratum P.I. 134417 and the L. esculentum cultivar "Manapal" the correlation between the absorbance values obtained using the colorimetric assay and the amount of 2TD per unit leaf area determined using gas chromatography was 0.95. Id. The absorbance value for each F 2 plant in a group was determined as the average absorbance at 480, 510, and 540 nm. Because 2TD has been found to be significantly more abundant in the foliage of hirsutum plants grown under long-days compared to short-days, the colorimetric absorbance values of individuals in each of the 9 groups were adjusted to a percentage of the hirsumtum parent. From each of the 9 groups, 7 to 10 plants were chosen which represented a wide range of absorbance values. A total of 74 plants were selected and maintained in the greenhouse.
Cuttings from each of the 74 test plants were rooted and grown in a uniform greenhouse environment and later reevaluated colorimetrically for 2TD. Sufficient leaf tissue was harvested from each plant to provide a 5 g dry weight sample for RFLP analysis. The procedures for plant DNA preparation, restriction enzyme digestion, Southern blotting, preparation of radioactive probes, and hybridization have been described in a previous publication (Helentjaris et al. I). A further description of methodologies used in the selection of useful marker clones in a tomato population is detailed in a companion publication (Helentjaris et al. II).
A two phase screening process was used to identify the RFLPs associated with expression of 2TD. In the first screen, a sample 36 RFLPs were evaluated on all 74 test plants. The 36 selected RFLPs were chosen to be approximately 10 to 20 centimorgan map units apart with at least one RFLP selected from each of the 20 defined linkage groups. Helentjaris et al. II. In the second screen, flanking RFLP markers on linkage groups identified in the first screen to be associated with expression of 2TD were evaluated. In the second screen, 46 F 2 test plants, which represented the widest range of 2TD expression, were used. The degree of association between individual RFLPs and absorbance values for 2TD were indicated by the magnitude of the linear correlation of colorimetric absorbance values with hirsutum allele frequency.
In the second experiment, parental, F 1 , and F 2 plants were grown in Conviron growth chambers at 20° C. day and 15° C. night temperatures with a constant 16 hr. photoperiod. To facilitate laboratory analysis, the test plants were planted in 6 blocks of 25 plants each, which included parental, F 1 and 22 F 2 plants. At the three leaf stage 5 leaf disks were sampled, using the same procedure as in the previous experiment, and evaluated colorimetrically for 2TD expression. Based on these analyses, 16 F 2 plants were selected from each block which represented the widest range of expression for colorimetric absorbance values. Five additional 1 cm 2 leaf disks were sampled from the margins of leaflets from each of the 3 largest leaves on each selected F 2 plant and the number of type VI trichomes/leaf disk determined. Sufficient leaf tissue was harvested from the 96 selected F 2 plants to provide at least 5 g dry weight for RFLP analyses. Procedures for DNA extraction and Southern blotting were the same as outlined in the above experiment. Two closely linked RFLP loci from regions on each of the three linkage groups identified in the first experiment as being associated with QTLs affecting colorimetric absorbance (2TD) were used as probes in the second experiment.
The number of F 2 individuals in each of the three genotypic classes, homozygous esculentum (e/e), heterozygous (e/h) or homozygous hirsuteum (h/h) at each RFLP was determined and chi-square goodness-of-fit statistics calculated for 1:2:1 Mendelian segregation ratio. Linear and quadratic contrasts among the three genotypic classes at each RFLP were used to predict the degree and type of gene effect for colorimetric absorbance (2TD) and trichome density. Main effects of the RFLPs associated with colorimetric absorbance, and first and second order interactions among them, were fit in multiple regression model to maximize the coefficient of determination.
In experiment 1 the correlation of colorimetric absorbance values between individuals in each of the 9 groups and the subsequent evaluation of cuttings in a uniform environment was 79% (data not shown). The magnitude of this correlation coefficient suggests that genotype-by-environment interactions for the colorimetric absorbance values were small. Hence, the mean of the two colorimetric evaluations was used in the analysis.
The magnitude of the correlation coefficients between the three genotypic classes, e/e, e/h and h/h, for each RFLP and colorimetric absorbance values in experiment 1 suggested that regions on three different linkage groups, C, D and I, were associated with the expression of 2TD (FIG. 2). The RFLPs on each linkage group with the highest correlation to the colorimetric absorbance values were C56, D68 and I38. The magnitude of the correlation coefficients for flanking RFLPs tended to decrease with increasing map distance from the RFLP with the highest correlation coefficient. Two RFLPs, C56 and D68, were located on the ends of linkage groups, and it is possible that the associated QTL was not flanked on both sides by identified RFLPs. When other RFLPs are localized adjacent to C56 and D68, determination of whether they are more highly correlated with the QTLs affecting expression of 2TD than C56 and D68 will be possible. Nevertheless, the results of experiment 1 provided an initial identification of 3 chromosomal regions associated with the expression of colorimetric absorbance (2TD).
In experiment 2, genotypic frequencies for the 2 RFLPs on each of the 3 linkage groups all deviated from the expected Mendelian 1:2:1 ratio (Table 3). Deviation from expected Mendelian segregation in populations derived from crosses between L. esculentum and L. hirsutum f. glabratum accessions have previously been observed, Zamir et al., Genetics 101:129-137 (1982), and have been attributed to gametic selection under low temperatures for gametes containing hirsutum chromosomes. In experiment 2 the tendency for F 2 individuals to have a higher gene frequency for hirsutum alleles may also have been aggravated by selection for the 16 F 2 individuals within each group of 22 which had low absorbance values and which were, therefore, more likely to have esculentum alleles. In spite of higher gene frequency for hirsumtum alleles, ranging from 0.67 to 0.75 (data not shown), the distribution of colorimetric absorbance value, for the 96 selected F 2 individuals used in experiment 2 was highly skewed towards low absorbance values (FIG. 3). The effect of this shift in gene frequency was to reduce the variance among genotypic classes at each RFLP, which would otherwise be maximized at a gene frequency of 0.50, concurrently reducing the magnitude of the covariance between gene frequency and phenotypic value.
The analyses of variance among the 3 genotypic classes was partitioned into two orthogonal contrasts (Table 4). The linear contrast was significant for all RFLPs except RFLP C56, in which the quadratic contrast was significant. The coefficients of determination for simple regression ranged from 0.05 for the RFLP on linkage group C to 0.17 for RFLP D81. The average effect of an allelic substitution was calculated as the linear regression coefficient of phenotypic value (colorimetric absorbance values) on gene frequency. These results suggest that the type of gene action associated with expression of 2TD was predominantly additive, except for the QTL linked to RFLP C56, in which gene action was non-additive.
2-tridecanone is localized in the tips of type VI glandular trichomes in hirsutum, and the amount of 2TD per unit area of foliage is the product of the number of trichomes and amount of 2TD per trichome. Thus, a component of 2TD expression is the number of trichomes per unit area. Because the number of trichomes per unit area is a function of leaf development (size), the trichome counts per leaf disk were adjusted by analysis of covariance for the size of the leaflet from which each disk was punched (data not shown). In the analyses of variance of adjusted trichome number, the mean square for the linear contrast for RFLP D68 was the largest (Table 5). This suggests that of the RFLPs associated with expression of 2TD, D68 may be primarily associated with the expression of type VI trichome density.
The development of a model to predict 2TD expression based on the genotype of RFLPs was complicated by the high correlation of genotypic values between the pairs of RFLP on each of the 3 linkage groups. To avoid the problem of multicolinearily (or high correlation) between linked RFLP, the linear contrast of the RFLP with the largest effect on each of 3 linkage groups was included in the regression model (Table 6). In addition, the quadratic contrast for RFLP C56, which is orthogonal to the linear contrast for RFLP C22, was included in the regression model. The regression model, which included main effects of each of the 4 RFLPs as well as significant first and second order interactions, accounted for over 38% of the total phenotypic variance for absorbance values (Table 6). The interactions observed among the linear contrasts for RFLPs C22, DS1 and I28 would suggest that additive by additive epistatic interactions among the linked QTL loci are important in the expression of colorimetric absorbance values (2TD).
The plot of observed vs. predicted absorbance values revealed that 39 of the 96 F 2 individuals in the population had absorbance values above the observed mean. 23 of the 39 had been predicted to be above the mean based on the regression model (FIG. 4). The plot of observed vs. predicted colorimetric absorbance further indicated that the multiple regression model would better predict individuals with low rather than high colorimetric absorbance values. Inspection of residual plots revealed that the errors associated with the prediction of individuals with high absorbances values were much larger than those for low value individuals (FIG. 5). Moreover, the nonrandom pattern of the residuals suggested a systematic deviation.
If the failure of RFLPs to better predict observed phenotypes were due to recombination between the marker RFLP's and their associated QTLs the pattern of residuals would be expected to be a random scatter about a mean of zero. In contrast, if the failure of RFLPs to better predict the phenotype were due to the inability to identify an RFLP locus associated with a QTL with major effects, then the residuals would be expected to be larger for individuals which were observed to be high in phenotypic value. Inspection of the residual plots for experiment 2 suggest that one or more additional QTLs, which were not identified as linked to the RFLPs may be associated with expression of 2TD.
TABLE 3______________________________________Genotypic frequencies for 2 RFLP oneach of 3 linkage groups (experiment 2).RFLPC22 C56 D81 D68 138 128Genotype No.______________________________________e/e 6 6 5 6 5 5e/h 47 47 53 49 37 36h/h 42 42 38 37 52 53X.sup.2 27.3** 27.3** 27.7** 21.3** 51.3** 54.2**______________________________________ * e/e = esculentum homozygote, e/h = heterozygote, and h/h = hirsutum homozygote ** indicates signficant deviation from expected 1:2:1 segregation ration at 0.01 level.
TABLE 4__________________________________________________________________________Analysis of variance mean squares and genotypic means for colorimetricabsorbance values (2TD) for 2 RFLP on each of 3 linkage groups(experiment 2).__________________________________________________________________________ RFLP d.f. C22 C56 D81 D68 138 128Source d.f. Mean squares__________________________________________________________________________Geneotypes 2Linear 1 678968* 125601 3042549* 1962483* 1802941* 1839632*Quadratic 1 10476 218063* 2121063 1042812 193528 686236Dev. from 191785 191162 166195 176424 182991 182597Regression 92r.sup.2 0.05 0.05 0.17 0.11 0.08 0.10__________________________________________________________________________ MeansGeneotype* Number__________________________________________________________________________e/e 114 114 200 207 86 86e/h 464 525 338 366 371 372h/h 538 474 694 639 587 591Average effect 140 + 75 60 + 76 310 + 72 245 + 73 232 + 73 234 + 74of an allelicsubstitution +__________________________________________________________________________ *Significant at 0.05 level. +See Table 1 for an explanation of geneotype symbols. +Linear regression coefficient and standard error, respectively.
TABLE 5__________________________________________________________________________Analyses of variance mean squares and genotypic means for number oftype VI trichomes/cm.sup.2 for 2 RFLP on each of 3 linkage groups(experiment 2).__________________________________________________________________________ RFLP C22 C56 D81 D68 I38 I28Source d.f. Mean squares__________________________________________________________________________Geneotypes 2Linear 1 711.9 822.1 384.4 1597.7+ 1022.0 1093.7Quadratic 1 440.2 344.3 71.5 417.1 355.3 404.4Dev. from 484.4 484.5 509.1 498.1 510.9 511.6Regression 92r.sup.2 0.06 0.06 0.01 0.04 0.02 0.02__________________________________________________________________________ MeansGeneotype+ Number__________________________________________________________________________e/e 29 29 43 39 41 41e/h 52 52 49 48 47 48h/h 51 51 52 54 53 53Average effect 4.6 + 3.8 4.9 + 3.8 3.5 + 4.0 7.0 + 3.9 5.5 + 3.9 5.7 + 3.9of an allelicsubstitution°__________________________________________________________________________ *Significant at 0.05 level. +See Table 1 for an explanation of genotype symbols. °Linear regression coefficient and standard error, respectively.
TABLE 6______________________________________Estimates for partial regression coefficients using linear andquadratic contrasts among the 3 genotypic classes at 4 RFLP topredict colorimetric absorbance value (2TD) (experiment 2). Parameter estimatesVariable* Coefficient Std. error______________________________________Constant 241.8 61.2L-C22 63.6 75.8L-D81 165.0 75.4L-I28 132.0 66.8Q-C56 -52.9 28.9L-C22 × L-D81 277.1 110.9L-C22 × L-D81 × L-I28 220.6 123.0______________________________________ *L and Q indicate the linear and quadratic contrasts among the 3 genotypi classes at each RFLP, respectively.
EXAMPLE II
The overall objective of this experimental on water-use efficiency was the development of more water-use efficient crop cultivars, i.e., in spite of being more conservative water users. Water-use efficient cultivars would result in reduced cost and volume of supplemental irrigation, in the reclamation of marginal land for farming purposes, and in minimization of the rate and extent of man-made soil salinization.
Measurement of the relative water-use efficiency of an array of many hundreds of breeding lines requires expensive specialized equipment and many man hours of labor. Currently, the most precise measurement of the season long water-use efficiency of a specific plant genotype is through determination of the relative abundance of stable carbon isotopes of plant tissue samples. The ratio of stable carbon isotopes has been shown to correlate well with stomatal behavior and the water-use efficiency of the plant. The computed parameter is the ratio of isotopes of Carbon 13 to Carbon 12 in the plant tissue. Although the measurement of stable carbon isotopes is a very accurate measure of the water-use efficiency of a plant, determination of relative abundance of carbon isotopes is expensive.
Therefore, the specific objective of this research was to identify RFLPs associated with the ratio of Carbon 13 to Carbon 12 and, hence, to water-use efficiency of the plant. Identification of associated RFLPs will permit more efficient selection of water-use efficient genotypes by permitting evaluation of seedlings grown in the greenhouse at any time during the year, rather than having to grow the genotypes to maturity in water deficient environments in the field.
A wild species of tomato from the arid regions of Peru, Solanum pennellii, has been reported to be tolerant of drought conditions (Rick 1982). F 1 hybrids were obtained between S. pennellii and UC82, a cultivar of the domesticated tomato Lycopersicon esculentum. The F 1 hybrid was self-pollinated to produce a segregating F 2 population. Seeds were harvested from individual F 2 plants to produce F 3 families. Over 100 F 3 families were grown in a replicated trial in Visalia, Calif. under optimum water availability. The F 3 families were also grown in a replicated trial at the same time and location at 1/3 of optimum water availability, i.e., in a water deficient environment. Leaf tissue samples were harvested from each of the F 3 families grown in the water deficient environment, and the water-use efficiency determined from the ratio of stable carbon isotopes. The F 3 families were ranked from high to low based on their water-use efficiency, and the ten highest and ten lowest families were selected for RFLP analysis. Remanent F 3 seed of the 20 selected families was sown in the greenhouse and, when sufficient growth had occurred, leaf tissue was harvested and the DNA extracted for RFLP analysis. The procedures for DNA extraction and Southern blotting were identical to those used in the experiments outlined above.
Seventeen random RFLPs located on 14 different linkage groups were screened for association with expression of water-use efficiency (FIG. 6). Three RFLPs located on 3 different linkage groups, B85, F4 and Q90 were found to be associated with expression of water-use efficiency (Table 7). The linear contrasts among genotype means were significant for all 3 RFLPs, and in addition, the quadratic contrast was significant for RFLP Q90. This suggests that although the predominant type of gene action involved in the expression of water-use efficiency was additive, some dominant gene action was associated with one RFLP.
A multiple regression model was developed which included main effects for the linear contrast at 3 RFLP plus the quadratic effect for RFLP Q90 (Table 8). The multiple regression model accounted for 70% of the observed phenotypic variance for water-use efficiency (FIG. 7). The magnitude of the correlation between observed vs. predicted water-use efficiency suggests that indirect selection for genotypes at 3 RFLP should be effective in selection for improved water-use efficient cultivars.
No systematic deviation from randomness was observed in the plot of residuals from the multiple regression model vs. observed water-use efficiency (FIG. 8). This suggests that, although only 17 RFLPs were screened, the major RFLPs associated with expression of water-use efficiency were identified.
TABLE 7______________________________________Analysis of variance, linear and quadratic contracts,genotype means and linear regression coefficients for 3RFLPs associated with expression of water-use efficiency.______________________________________Source d.f. B85 F04 Q90______________________________________Genotype 2linear 1 2.912* 3.929* 4.252**quadratic 1 0.723 0.006 3.193*Error 18 0.650 0.721 0.397______________________________________Genotype means______________________________________e/e -25.36 -25.31 -25.61e/p -25.49 -25.83 -25.51p/p -26.49 -26.44 -27.11Linear regression 0.66 ± .25 0.57 ± .23 0.88 ± .27coefficient ±Std. errorr.sup.2 0.28 0.26 0.39______________________________________
TABLE 8______________________________________Multiple regression model, using genotypicvalues at 3 RFLPs to predict water-use efficiency. Parameter Estimate Std. Error______________________________________ intercept -25.936 .163linear B85 0.292 .222linear F04 0.241 .187linear Q90 0.555 .241quadratic Q90 -.241 .097r.sup.2 = 0.702______________________________________
EXAMPLE III
Among the traits in tomato which are of greatest importance to the processing industry is the soluble solids (SS) content of the fruit, which includes fructose, glucose and other sugars. Tomatoes used in formulating solids-based products are often priced according to their SS content and, because of the large amount of tomatoes grown worldwide for processing, small increases in the SS content of the raw tomatoes can have an enormous economic impact. Although the cultivated tomato (Lycopersicon esculentum) is relatively low in SS (approximately 5%), some wild relatives of the tomato have much higher proportions. One accession, LA 1028, of a wild relative (L. chmielewskii) has an SS content of approximately 10%. The heritability of SS is relatively low in adapted populations and, in addition, expression of SS in tomato fruit is known to be affected by both environment as well as genotype by environment interaction effects. Hence, the heritability of SS is low.
The objective of this experiment was the identification of RFLP genetic markers linked to a gene or genes conferring high SS in tomato fruit. Such information will be very useful in facilitating the development of tomato cultivars with higher levels of SS compared to currently grown varieties.
F 1 Hybrids were produced from a cross between L. chmielewskii accession LA 1028 and UC82, a widely grown processing tomato cultivar. F 2 seeds were harvested from the F 1 plants, and grown as individual plants. Fruits were harvested from each of 250 individual F 2 plants and the seed extracted. These seeds represented F 3 families corresponding to each individual F 2 plant. One hundred F 3 families were grown in a replicated trial in Visalia Calif. Each plot included 30 plants spaced 6 inches apart and each family was replicated 3 times in a 10×10 triple lattice experimental design.
SS content of fruit were evaluated at 3 times: (1) approximately 10 days before the check cultivar UC82 was fully mature, (2) at full maturity of UC82, and (3) 10 days after UC82 was fully mature. At each SS evaluation 25 fruit were harvested from each plot. The fruit were ground in a blender and the percentage SS in the filtered juice was measured as degrees Brix on a refractometer.
Leaf tissue samples were harvested from each F 3 family grown in the field, and DNA extracted for RFLP analysis using the same procedures used in previous experiments. Ninety nine (99) RFLPs were screened for association with the expression of SS. Of the 99 RFLPs screened, 7 loci on 7 different linkage groups were found to be associated with the expression of SS (FIG. 9).
Analysis of variance was computed for the 7 RFLPs associated with expression of SS, and the 3 genotypic classes at each RFLP (i.e., e/e, e/c and c/c) were partitioned into linear and quadratic contrasts (Table 9). Both the linear and quadratic contrasts were significant for RFLPs T031, T096, T090 and T020. For all 4 RFLPs however, the linear contrast was consistently larger than the quadratic. Only the linear contrasts were significant for RFLPs T069 and T009. In contrast, only the quadratic contrast was significant for RFLP T050. The results would suggest that, although additive gene action was predominant in the expression of SS for most RFLP non-additive (dominant) type gene action was also of some importance.
The 7 RFLPs were fit in a stepwise multiple regression model to select the most predictive RFLP (Table 10). The final prediction model included linear and quadratic main effects for individual RFLPs as well as first-order (epistatic) interaction effects for pairs of RFLPs. The coefficient of determination (r 2 ), i.e., the amount of phenotypic variance for SS which could be accounted for by the multiple regression model, was 56% (Table 10).
The correlation between observed and expected expression of SS based on the RFLP regression model was 0.75 (FIG. 10). The magnitude of the correlation suggests that genotypes of RFLPs can be used to predict SS of tomato fruit. This result permits the identification of tomato genotypes grown in the greenhouse which would be expected to have higher levels of expression of SS. A systematic deviation from randomness was observed in the plot of residuals (deviations of observed vs. predicted values) against observed SS (FIG. 11). The pattern of residuals would suggest that one or more additional RFLPs which were not identified in this study may be important in the expression of SS.
TABLE 9__________________________________________________________________________Analysis of variance, linear and quadratic contrasts,genotype means, and linear regression coefficient for 7 RFLPsassociated with the expression of soluble solids in tomato fruit.Source d.f. T031 T096 T090 T050 T069__________________________________________________________________________Rep 2 1.08 1.10 1.02 1.12 0.90Genotype 2 -- -- -- -- --Linear 1 18.272** 18.932** 5.00** 4.29 25.82**Quadratic 1 6.45* 9.004* 3.39* 17.44** 1.97Rep × Genotype 4 0.44 0.98 0.32 1.06 0.76Pool W/I Genotype 291 1.59 1.70 1.75 1.67 1.68e/e 7.25 7.92 7.56 7.45 7.27e/c 8.09 7.93 7.98 8.15 7.95c/c 8.23 7.19 7.94 7.81 8.27Linear RegressionCoefficient + 0.64 ± .18 -0.29 ± .15 0.24 ± .16 0.30 ± .16 0.58 ± .17Std. Error__________________________________________________________________________
TABLE 10______________________________________Multiple regression coefficients using 5 RFLPs topredict the level of soluble solids in tomato fruit.Parameter Coefficient Std. Error______________________________________Intercept 7.83 0.10Linear T020 0.51 0.13Linear T031 0.43 0.15Linear T096 -0.48 0.11Linear T050 0.12 0.12Linear T069 0.28 0.14Quadratic T050 0.12 0.06Quadratic T020 0.22 0.06Linear T031 × Linear T069 -0.50 0.22Quadratic T020 × Quadratic T069 -0.09 0.03Linear T096 × Quadratic T050 0.15 0.07r.sup.2 = 0.56______________________________________
EXAMPLE IV
Among the traits in tomato which are of interest to the processing industry is the size (weight) of tomato fruit. Tomato fruit which are too small cannot be efficiently harvested with mechanized tomato harvesting equipment. In contrast, tomatoes which are too large are subject to greater damage from crushing in transport from the field to the processing plant.
The cultivated tomato Lycopersicon esculentum is relatively low in tomato fruit weight (approx. 5%), although some wild relatives of the tomato have much higher fruit weight proportions. One accession, LA 1028, of a wild relative, L. chmielewskii, has a tomato fruit weight content of approximately 10%. We have used RFLP technology and crosses involving L. chmielewskii to increase the soluble solids content of tomato fruit, as noted above. Because the L. chmielewskii tomato fruit are quite small, about 2 cm in diameter, we were also interested in improved fruit size.
The objective of this experimental study was the identification of RFLP genetic markers linked to a gene or genes associated with the expression of tomato fruit weight. Such information will prove very useful in facilitating the development of tomato cultivars which combine higher levels of tomato fruit weight with adequate fruit size.
F 1 hybrids were produced from a cross between L. chmielewskii accession LA 1028 and UC82, a widely grown processing tomato cultivar. F 2 seeds were harvested from the F 1 plants, grown as individual plants, and the seed extracted. These seeds represented F 3 families corresponding to each individual F 2 plant. One hundred F 3 families were grown in a replicated trial in Visalia, Calif. Each plot included 30 plants spaced 6 inches apart and each family was replicated 3 times in a 10×10 triple lattice experimental design.
Fruit weight was evaluated at 3 times: (1) approximately 10 days before the check cultivar UC82 was fully mature, (2) at full maturity of UC82, and (3) 10 days after UC82 was fully mature. At each occasion, 25 fruit were harvested from each plot and total fruit weight determined. Average fruit weight was calculated as total fruit weight divided by the number of fruit harvested from each plot.
Leaf tissue samples were harvested from each F3 family grown in the field and DNA was extracted for RFLP analysis by the same procedure used in the above Examples. Ninety nine (99) RFLPs were screened for association with the expression of tomato fruit weight. Of the 99 RFLPs screened, 6 RFLPs on 6 different linkage groups were found to be associated with the expression of tomato fruit weight (FIG. 12).
Analysis of variance was computed for the 6 RFLPs associated with expression of tomato fruit weight and the 3 genotypic classes at each RFLP (i.e., e/e, e/c and c/c) were partitioned into linear and quadratic contrasts (Table 11). Both the linear and quadratic contrasts were significant for all RFLPs. The linear contrast was consistently larger than the quadratic, except for RFLP T009, in which the quadratic contrast was larger. The results suggest that although additive gene action was predominant in the expression of tomato fruit weight for most RFLPs non-additive (dominant) type gene action was also of some importance.
The 6 RFLPs were fit in a stepwise multiple regression model to select the most predictive RFLPs (Table 12). The final prediction model included linear and quadratic main effects for individual RFLPs as well as first-order (epistatic) interaction effects for pairs of RFLPs, and a complex interaction term involving 5 RFLPs. The coefficient of determination (r 2 ), i.e., the amount of phenotypic variance for tomato fruit weight which could be accounted for by the multiple regression model was 59% (Table 12).
The correlation between observed and expected expression of tomato fruit weight (based on RFLP regression model) was 0.77 (FIG. 13). The magnitude of the correlation demonstrates that genotypes of RFLPs can be used to predict weight of tomato fruit. This result permits the identification of tomato genotypes grown in the greenhouse which would be expected to have higher levels of expression of tomato fruit weight.
A systematic deviation from randomness was observed in the plot of residuals (deviations of observed vs. predicted values) vs. observed tomato fruit weight. The correlation between residuals and observed values was 63% (FIG. 14). The magnitude of this correlation suggests that one or more additional RFLPs which were not identified in this study, may be important in the expression of tomato fruit weight.
TABLE 11__________________________________________________________________________Analysis of variance, linear and quandratic contrasts, genotype means,andlinear regression coefficients for 6 RFLPs associated with expression offruit weight.__________________________________________________________________________Source d.f T020 T009 T069 T090 T099 T096__________________________________________________________________________Rep 2 58.50 51.3 56.4 59.8 66.2 58.6Genotype 2 -- -- -- -- --linear 1 6164.0** 316.3** 1561.0** 2547.9** 909.6** 1317.5**quadratic 1 1182.3** 696.0** 493.3** 197.2** 400.6** 567.6Rep & Genotype 4 8.68 18.9 15.8 11.9 24.44 15.0W/I genotype error 282 114.5 119.5 134.0 129.7 133.1 132.8__________________________________________________________________________ MEANS (grams)__________________________________________________________________________e/e 18.85 9.79 15.17 14.13 12.39 13.74e/c 8.07 8.15 8.53 8.08 6.83 7.77c/c 5.38 12.79 7.50 5.54 7.07 7.69linear regression -6.92 1.64 -4.39 -4.56 -3.33 -3.57coefficient ± ±1.50 ±1.48 ±1.75 ±1.50 ±1.53 ±1.52__________________________________________________________________________
TABLE 12______________________________________Multiple regression coefficients using6 RFLPs to predict tomato fruit weight.Parameter Coefficient Std. Error______________________________________Intercept 6.75 1.07T020 0.75 1.59D009 0.76 0.51T069 -1.50 1.31T090 -2.39 1.22T099 -1.67 1.08T096 -0.12 1.12T020 × T069 2.94 1.77T020 × T090 5.04 1.96T020 × T099 2.78 1.64T020 × T096 4.69 1.56T090 × T096 3.64 1.63T020 × T069 × T090 × T099 × T096 -8.33 3.12r.sup.2 = .59______________________________________
EXAMPLE V
In previous Examples, we have demonstrated the ability of RFLP analysis to improve selection for quantitatively inherited traits. The objective of this experiment was to develop RFLP analysis to facilitate simultaneous selection for multiple traits. The specific objective was to develop a RFLP selection index to permit simultaneous increases in soluble solids (SS) and fruit weight (FW) in tomato.
As noted, the cultivated tomato (Lycopersicon esculentum), is relatively low in SS (approx. 5%), although some wild relatives of the tomato have much higher proportions. One accession, LA 1028, of a wild relative, L. chmielewskii, has a tomato SS content of approximately 10%. We used crosses involving L. chmielewskii to increase the soluble solids content of tomato fruit, but, because the L. chmielewskii tomato fruit are quite small (about 2 cm in diameter), we were also interested in improved fruit size.
F 1 Hybrids were produced from a cross between L. chmielewskii accession LA 1028 and UC82, a widely grown processing tomato cultivar, and F 2 seeds were harvested from the F 1 plants and grown as individual plants. Fruits were harvested from each of 250 individual F 2 plants and the seed extracted. These seeds represented F 3 families corresponding to each individual F 2 plant. One hundred F 3 families were grown in a replicated trial in Visiala, Calif. and Malloa, Chile. Each plot included 30 plants spaced 6 inches apart and each family was replicated 3 times in a 10×10 triple lattice experimental design.
Fruit Weight (FW) and soluble solids (SS) content of the tomato was evaluated at 3 times: (1) approximately 10 days before the check cultivar UC82 was fully mature, (2) at full maturity of UC82, and (3) 10 days after UC82 was fully mature. At each occasion 25 fruit were harvested from each plot and total FW determined. Average fruit weight was calculated as total fruit weight divided by the number of fruit harvested from each plot. The fruit were ground in a blender and the percentage SS in the filtered juice was measured as degrees Brix on a refractometer.
Leaf tissue samples were harvested from each F3 family grown in the field and DNA extracted for RFLP analysis using the same procedures used in previous Examples. Ninety nine (99) RFLPs were screened for association with the expression of tomato FW and SS content in California and Chile. Of the 99 RFLPs screened, 7 RFLPs on 7 different linkage groups were found to be associated with the three traits of interest, FW, SS Calif. and SS Chile (FIG. 15).
A matrix (Matrix A) was developed which included the linear regression coefficients (Table 13) for each of the 3 traits for each of the 7 RFLPs. The regression coefficients measure the linear effects of each of the RFLPs on expression of the 3 traits. The regression coefficients were standardized to a distribution with mean equal to 0 and variance equal to 1. The standardization permitted the distribution of the 3 traits to be expressed in units of standard deviations and, thus, direct comparisons could be made among the magnitudes of the regression coefficients for each of the 3 traits. The magnitudes of the standarized regression coefficients for all three traits suggest that each of the RFLPs had pleiotropic effects, i.e., that each RFLP was associated with the expression of more than one plant characteristic.
Two vectors (matrices of only 1 column) were developed to represent the relative economic weights of the 3 traits of interest (Table 14). The economic weights chosen for each trait represent the relative importance and direction of selection for each traits. For example, values of +1, 0 and -.5 would represent the desire to increase the first trait by one unit, maintain the second trait, and decrease the third trait by one half unit, respectively. In this Example, the vector B1 had unit values assigned to SS Chile and SS Calif and zero for fruit weight. In practical terms, vector B1 represents the desire to increase SS in both Calif. and Chile with no change in FW, i.e., broad adaption for soluble solids in both environments. In contrast, vector B2 had unit values assigned to each of the three traits. This would represent the desire to increase all 3 traits simultaneously, with equal weights.
The products of the matrix multiplication of A *B1 and A *B2 are the regression coefficients weighted by their relative economic values. The products of this multiplication are presented in Matrix C (Table 15).
Ten F 2 plants were subjected to RFLP analysis, and their genotypes at 7 RFLPs determined. A matrix (Matrix D) was constructed which contained this information (Table 16). The coded genotypic values for each RFLP were as follows: -1=e/e esculentum homoygotes, 0=e/c heterozygotes, and 1=c/c chmielewskii homozygotes.
Multiplication of the RFLP genotypes of each F2 plant, Matrix D, by the weighted regression coefficients, Matrix C, results in relative selection index values for each plant, Matrix E (Table 17). The vector B1 represents the selection value of each plant if we wished to select for SS in Calif. and Chile alone. The values can be ranked for purposes of selection. Thus, in this case, the genotypes most likely to result in increased SS in both Calif. and Chile are 57, 26, 60, 75 and 121, in that order. In contrast vector B2 represents the value of each genotype if the objective were to increase SS and FW in both environments. The ranking of the two vectors is similar, except that the value of genotype 121 and 78 is increased relative to the others.
The development of RFLP selection indices permits simultaneous selection for several quantitatively inherited traits as well as environmental adaption. The index could easily be expanded to include many other traits, as the resources necessary for RFLP determination is the same if one considers one or many traits. In practical terms, the construction of RFLP indices greatly facilitates selection, as the RFLP genotype of a plant can be determined from seedlings grown in the greenhouse in the off-season. RFLP selection indices also offer significant advantages over the "intuitive indices" which are merely subjective evalutions of overall performance.
The "B" vectors could be defined to give relative economic weight to an array of plant characteristics. Alternatively, however, they could be used to weigh the importance of several environments. For example, if large genotype by environment interactions were observed for an array of genotypes over several target environments, the "B" vectors could be constructed either to select genotypes best adapted to a specific environment, or to select genotypes with broad adaptation over a range of environments.
TABLE 13______________________________________Matrix A. Matrix of standardized regressioncoefficients for 7 RFLPs associated withsoluble solids measured in Californiaand Chile, plus fruit weight measured in California.sup.2.RFLP Soluble SolidsLocus Calif. Chile Fruit Weight______________________________________96 -.229 -.056 -.13190 .221 .038 -.29231 .433 .335 -.268 9 -.245 -.285 .25150 .161 .171 -.19869 .320 .278 -.26920 .434 .173 -.474______________________________________ .sup.2 Standardization regression coefficients are coefficients calculate on distribution of soluble solids and fruit weight which are transformed to "standard" distribution with mean = 0 and standard deviation = 1.
TABLE 14______________________________________Matrix B. Vector of economic weights. Vector B1 Vector B2______________________________________Soluble Solids 1 1CaliforniaSoluble Solids Chile 1 1Fruit Weight 0 1______________________________________ 1 This vector would give equal weight for both solids in Californa and Chile. 2 This vector would weight solids in California and Chile plus fruit weight.
TABLE 15______________________________________Matrix C. Products of Matrix Multiplicationof A by B and B. The products of this multiplicationare vectors of weighted regression coefficients.RFLP Locus A × B1 A × B2______________________________________96 -.285 -.41690 .249 -.04331 .968 .500 9 -.530 .27950 .332 .13469 .598 .32920 .607 .133______________________________________
TABLE 16______________________________________Matrix D. Genotypes of 10 tomato plants at 7 RFLPs.*RFLP GenotypesPlant96 90 31 9 50 69 20______________________________________26 0 -1 1 -1 1 1 057 -1 1 1 -1 0 1 160 -1 0 1 -1 0 0 064 0 0 -1 1 -1 0 165 1 0 0 0 0 0 068 1 1 0 0 1 0 -174 1 -1 0 1 0 0 175 -1 0 -1 -1 1 0 078 -1 -1 1 1 0 -1 -1121 -1 0 1 0 -1 -1 0______________________________________ * -1 = e/e, esculentum homozygote 0 = e/e, heterozygote 1c/c, chmielewskii homozygote
TABLE 17______________________________________Matrix E. Relative selection indexvalues for 10 F.sub.2 tomato plants.Plant B1 Rank B2 Rank______________________________________26 1.979 2 1.285 257 3.037 1 1.614 160 1.583 3 1.195 364 -1.023 10 -0.780 1065 -0.285 6 -0.416 768 -0.311 7 -0.458 874 -0.457 8 -0.519 975 0.379 4 0.329 578 -0.931 9 0.218 6121 0.123 5 0.453 4______________________________________ .sup.1 Selection for increased soluble solids in both California and Chile. .sup.2 Selection for increased soluble solids in both California and Chil and fruit weight. | Methods of introgressing one or more desired quantitative traits into a plant comprising screening one or more restriction fragment length polymorphisms (RFLP) for association with desired quantitative traits (QT), selecting one or more RFLP's showing association with the desired QT's, developing a mathematical model based on the magnitude of the association of RFLP(s) to predict the degree of expression of the desired QT's, and using the thus-selected RFLP(s) and the mathematical model in a plant breeding program to predict the degree of introgression and expression of the desired QT's in plant progeny. | 2 |
BACKGROUND OF THE INVENTION
[0001] This application claims priority of Korean Patent Application No. 10-2003-0068837 filed on Oct. 2, 2003 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
[0002] 1. Field of Invention
[0003] The present invention relates to the authentication of devices present in a domain, and more particularly, to a method of constructing a unique domain for preventing content from being illegally used by an unauthorized third person in a public key-based architecture and applying the constructed domain to a home network using universal plug and play (UPnP).
[0004] 2. Description of the Prior Art
[0005] As digital and communication technologies have increasingly advanced, a variety of content such as audio or video materials have become popular. There have been proposed a variety of techniques for protecting content against illegal copying and unauthorized distribution. In particular, there have been developed techniques by which content is encrypted and only particular devices can decrypt the encrypted content using predetermined rules. For example, the techniques include a DVD content scrambling system, content protection for recordable media (CPRM), digital transmission content protection (DTCP), high definition content protection (HDCP), content protection system architecture (CPSA), digital rights management (DRM) and the like.
[0006] Specifically, with the development of the home network field, there have been proposed techniques for protecting content on a home network. Typical examples of the techniques include “SmartRight” proposed by Thomson Corporation, “OCCAM (Open Conditional Content Access Management”) proposed by Sysco Corporation, or “xCP (extensible Content Protection) Cluster Protocol” proposed by IBM.
[0007] “SmartRight” is a technique by which each device constituting a home network has a smart card including a public key certificate and a key for the home network is created by the exchange of certificates among devices using the smart cards.
[0008] “OCCAM” is a technique by which respective devices in a home can use content by using a unique “ticket” for each piece of content.
[0009] “xCP Cluster Protocol” is a technique based on broadcast encryption, by which the concept of a domain called “cluster” is employed and devices belonging to the same cluster can freely use content among the devices.
[0010] As shown in FIG. 1 , conventional domain management comprises a master device 110 and slave devices 120 , 130 and 140 within an authenticated home domain 100 . Domain management is performed between the master device and the slave devices. The process of reproducing content based on the ‘xCP Cluster Protocol’ in accordance with such a configuration of the master device and the slave devices will be described with reference to FIG. 2 . The process can be roughly divided into the following processes: a cluster-forming process (S 201 ), a device-authenticating process (S 202 ), a content-encrypting process (S 203 ), and a content-decrypting process (S 204 ). The detailed description thereof will be made below. A server that initially connects with a given home network creates a binding ID (hereinafter, referred to as “ID b ”) for the home network (S 200 ). An ID b may be, a unique identifier for a server established upon manufacture of the server or arbitrarily established by a user. When an ID b is thus established, a cluster identified with ID b is formed.
[0011] When a device intends to use content present in the server, the device extracts a media key (hereinafter, referred to as “K m ”) from a media key block (MKB) by using its own device key set (S 210 ). Thereafter, the device creates its own unique key K p by using “K m ” extracted in step S 210 and its own identifier ID p (S 212 ).
[0012] When the device intends to go through device authentication, it requests the server to authenticate the device itself (S 214 ).
[0013] Specifically, the device sends its own unique “ID p ,” a “type” indicating the kind of device, and a hash value of the “type” and “ID p ” derived using “K p ,” i.e. h=MAC(ID p ∥type)K p , to the server present in the cluster or an authentication server present outside the home network.
[0014] The server obtains K p ′ from K m and ID p , and checks whether a hash value, h′=MAC(ID p ∥type)K p ′, which is obtained using K p ′, is identical to the value h already received from the device.
[0015] If it is determined that the value h is equal to the value h′, the server sends the device E(ID b ) K p , which is obtained by encrypting ID b using K p , and the unique identifier ID p of the device, and then adds ID p to an authentication table of the server, “auth.tab.” The authentication for the device can be accomplished by extracting ID b from E(ID b ) K p received from the server (S 216 ).
[0016] After the device authentication has been completed, the server encrypts content to be transmitted to the device (S 203 ). A binding key (hereinafter, referred to as “K b ”) is first created using ID b , auth.tab and K m . Here, K b meets a formula such as K b =H[ID b ⊕ H[auth.tab], K m ].
[0017] After K b is created, the server encrypts the content using a title key (hereinafter, referred to as “K t ”) for protecting the content (S 222 ). Meanwhile, each piece of content contains usage rule (UR) information including copy control information, information on whether the content is allowed to be distributed to the outside, a right to use the content, a valid use period, and the like. The UR information and K t are encrypted using K b to produce E(K t ⊕ H[UR]K b ) (S 224 ).
[0018] Meanwhile, the device receives the “auth.tab” from the server, and K b is obtained from K b =H[ID b ⊕ H[auth.tab], K m ] using the previously extracted K m and ID b (S 230 ). Further, after K t is extracted from E(K t ⊕ H[UR]K b ) (S 232 ), the content received from the server is decrypted using the extracted K t (S 234 ).
[0019] In the xCp cluster protocol operating as described above, all devices capable of communicating with the server can automatically join a domain without the process of selecting devices that will join the domain. Further, since ID b is fixed, the values of K b , K t , and the like can be calculated even when the device is put outside the domain. However, there is inconvenience in that whenever each device creates its new K b , the device should receive the auth.tab from the server to calculate the new K b . Accordingly, there is a need for more secure protection of content through construction of a unique home domain and involvement of a user in device authentication.
[0020] Meanwhile, DRM serves as an essential component in the development of the digital industry and also plays an essential role in a home network. Accordingly, an increased need exists for implementing the domain management model described above in the home network. As described above, the related art for applying the domain management technique to a home network uses a direct communication scheme between the master and slave devices in the home network, as shown in FIG. 1 . This scheme needs to develop communication protocols adapted for respective domain management. Thus, there is a problem in that compatibility with respective devices is deteriorated. Accordingly, measures to efficiently solve the problem are required. Recently, a lot of companies all over the world have been interested in UPnP (Universal Plug and Play), which has emerged as home network middleware, and produce many products supporting UPnP. UPnP has many advantages in that it can be smoothly incorporated into existing networks due to the use of conventional standard Internet protocols and does not depend on specific operating systems, physical media, or the like. However, since a method of implementing domain management through UPnP remains unknown, there is a need for a method of effectively implementing domain management using UPnP.
SUMMARY OF THE INVENTION
[0021] The present invention is conceived to solve the problems in the related art. An object of the present invention is to provide a method of more safely constructing a domain independent of the outside through the direct involvement of a user in constructing the domain, and preventing content from being illegally used by a third person.
[0022] Another object of the present invention is to provide a method of implementing more efficient domain management using UPnP when the domain-constructing method is applied to a home network.
[0023] According to an aspect of the present invention for achieving the objects, there is provided a method of constructing a domain based on a public key and implementing the domain through UPnP so that a unique domain can be constructed to allow only an authorized user to use content in a public-key based architecture in a home network, comprising a first step of selecting one of controlled devices that are operable as a master device and determining the selected device as the master device; a second step of performing device authentication in such a manner that other controlled devices receive a secret information block from the determined master device and create certificates; and a third step of determining slave devices by selecting one or more devices among the authenticated controlled devices.
[0024] The first step may comprise the steps of: notifying a control point that the controlled devices are connected; obtaining, by the control point, device information and DRM information of the controlled devices; selecting the master device among the controlled devices by using the DRM information; and setting the controlled device selected as the master device to a master mode and providing a list of devices to the controlled devices.
[0025] The second step may comprise the steps of: receiving, by the determined master device, the secret information block from an external server; delivering the received secret information block to the controlled devices except the master device; extracting secret values and creating the certificates using the delivered secret information block; and verifying the certificates and preparing a list of authenticated devices by using the created certificates, device IDs and public keys.
[0026] The third step may comprise the steps of: if the devices authenticated in the second step have no domain attributes, displaying a list of these devices to the user; selecting the slave devices among the listed devices; receiving a list of selected slave devices and creating a domain ID and a domain key; and encrypting the domain ID and the domain key using public keys.
[0027] In the method, important ones of functions of the control point in UPnP may be taken over by the master device and the control point deals with tasks related to user interfaces.
[0028] Further, the master device and the slave devices may be determined after manager authentication is performed by obtaining manager authentication information from the master device.
[0029] Moreover, selecting the master device and the slave devices may be performed by means of user selection through user interfaces.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The above and other objects and features of the present invention will become apparent from the following description of preferred embodiments given in conjunction with the accompanying drawings, in which:
[0031] FIG. 1 shows a conventional domain management configuration;
[0032] FIG. 2 is a flowchart illustrating the process of reproducing content based on ‘xCP Cluster Protocol’ in accordance with a conventional master-slave configuration;
[0033] FIG. 3 illustrates a method of constructing a domain in a public key-based architecture according to the present invention;
[0034] FIG. 4 is a block diagram showing an example in which the domain-constructing method of the present invention is applied to UPnP;
[0035] FIG. 5 illustrates a general UPnP operation performed between a control point and controlled devices;
[0036] FIG. 6 illustrates the process of determining a master device according to a first embodiment of the present invention;
[0037] FIG. 7 illustrates a device-authenticating process performed subsequent to the process illustrated in FIG. 6 according to the first embodiment of the present invention;
[0038] FIG. 8 illustrates the process of determining a slave device that is performed subsequent to the process illustrated in FIG. 7 according to the first embodiment of the present invention;
[0039] FIG. 9A shows a user interface for receiving a user's selection to select a master device;
[0040] FIG. 9B shows a user interface for receiving a manager ID and password from a user to authenticate a manager;
[0041] FIG. 9C shows a user interface for receiving a user's selection to select a slave device;
[0042] FIG. 10 illustrates the process of determining a master device according to a second embodiment of the present invention;
[0043] FIG. 11 illustrates a device-authenticating process performed subsequent to the process illustrated in FIG. 10 according to the second embodiment of the present invention; and
[0044] FIG. 12 illustrates the process of determining a slave device that is performed subsequent to the process illustrated in FIG. 11 according to the second embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0045] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0046] FIG. 3 illustrates a method of constructing a domain in a public key-based architecture according to the present invention.
[0047] For the sake of convenience of description of the present invention, it is assumed that each device requesting a master device, which provides content, to transmit content thereto has a set of unique secret keys and a public key or a public key-creating function upon manufacture of the device. At this time, the set of secret keys are used to extract a secret value from a secret information block (hereinafter, referred to as “SIB”) provided in a broadcast encryption manner. The SIB is information for verifying the revocation of devices. Revoked devices cannot extract an intended secret value from the SIB, whereas legitimate devices can extract a common secret value.
[0048] In a single domain, there is a master 320 involved in constructing a domain. The master 320 receives a SIB from an external server 310 in a broadcast encryption manner (S 332 ). Thereafter, the master 320 recognizes the presence of devices 330 in the domain in such a manner that the devices 330 inform the server that they exist in the domain or the master itself 320 discovers the devices 330 through a wired or wireless network (S 334 ).
[0049] When the master 320 provides a user with the devices 330 , which have been recognized by the master, by displaying them on a display unit of the master, the user selects devices 330 that the user wants to register with the domain among the displayed devices (S 336 ). Then, the master 320 sends the SIB, which have been already received from the external server 310 , to the devices 330 selected by the user (S 338 ). Each of the devices 330 that have received the SIB extracts a secret value from the SIB (S 340 ), and prepares a certificate for its own public key using the extracted secret value (S 342 ).
[0050] When each of the devices 330 sends its own certificate, unique identifier (ID) and public key to the master 320 (S 344 ), the master 320 verifies the certificate in order to verify that the device is a legitimate device (S 346 ). Then, the master 320 prepares an authentication list in which unique identifiers (IDs) and public keys of authenticated devices are recorded (S 348 ). The number of devices that can be authenticated is limited by a user.
[0051] After the master 320 prepares the authentication list, the master creates a unique domain ID and a domain key using information on the devices included in the authentication list and a random number created by the master itself (S 350 ). The domain ID is a secret key shared among only devices belonging to a domain formed by the user's selection and is simultaneously changed whenever there are changes in members constituting the domain. The domain ID is used as a discriminator for distinguishing a domain from other domains.
[0052] The master 320 encrypts the domain ID and the domain key using respective public keys of the authenticated devices 330 present in the domain and then transmits the encrypted domain ID and domain key to the authenticated devices 330 . The devices 330 restore the domain key using their own secret keys (S 354 ). Thus, the domain for using the content is finally formed. When the domain for sharing the content is formed, the master 320 encrypts the content using a content key that in turn is encrypted using the domain key. When the devices, which want to use the content, decrypt the encrypted content using the domain key, the devices can use the content.
[0053] FIG. 4 is a block diagram showing an example in which the domain-constructing method of the present invention is applied to UPnP.
[0054] Each of controlled devices 110 to 160 receives/sends commands and also provides their own services under the control of a control point 190 . A domain is constructed by designating one device of the controlled devices as a master device 110 and designating devices 120 , 130 and 140 , which have been selected by a user, among the remaining devices, as slave devices. Among the controlled devices, the devices 150 and 160 that have been not designated as master or slave devices, i.e. the ones that have not been included in the domain are called guest devices. The master device 110 and the slave devices 120 to 140 construct an authenticated home domain, and the control point 190 and the controlled devices 110 to 160 constructs a home network 200 as a whole.
[0055] FIG. 5 illustrates a general UPnP operation performed between the control point and the controlled devices. First, an addressing step is performed. UPnP networking is based on a TCP/IP protocol of which an essential point is an addressing function. Each device should have a dynamic host configuration protocol (DHCP) client. When the device is first connected to a network, the device searches for a DHCP server. If there is a DHCP server, the device uses an IP address allocated thereto. If there is no available DHCP server, the device uses an “auto IP” to secure an address.
[0056] Next, a discovery step is performed. Once the device is connected to the network and a proper address is allocated thereto, a discovery operation can be performed. The discovery operation is processed using a simple service discovery protocol (SSDP). When the device is added to the network, the SSDP functions to notify the control point present in the network of services provided by the device.
[0057] Next, a description step is performed subsequent to the UPnP networking. Although the control point has discovered the device, the control point still has little information on the device. If the control point intends to obtain detailed information on the device and its function and cooperates with the device, the control point should check a description of the device from a discovery message and a URL provided by the relevant device. The UPnP description of the device is expressed in XML, and includes unique manufacture information of the manufacturer of the device (for example, model name, serial number, manufacturer's name, manufacturer's URL, etc). Further, this description also includes lists of embedded devices and services as well as URLs for control, eventing and presentation.
[0058] After the aforementioned steps of addressing, discovery and description, a UPnP step is substantially performed. The UPnP step is performed through operations for control, eventing, presentation and the like. In the control operation, the control point secures a description of the device and then performs indispensable tasks for control of the device. In order to control the device, the control point sends an operation command to the device for a service provided by the device. To this end, the control point sends a proper control message to a control URL (available from the device description) for the device's service. The control message is also expressed in XML using a simple object access protocol (SOAP). In response to the control message, the relevant service then provides a specific operation value or a fault code.
[0059] In the eventing operation, when each device is subjected to a change in its status due to the reception of the command, it notifies the control point of the status change through an event message. The event message includes the names of one or more status variables and the current values of these variables, and is expressed in XML and formatted using a generic event notification architecture (GENA). The contents of the event are periodically updated and the control point is continuously notified of the updated contents of the event. Further, a subscription may be canceled using the GENA.
[0060] As for the presentation operation, if the device has a URL for presentation, the control point can search a page through the URL and load the page in a browser. Users can control the device or refer to the status of the device using the page. The level at which these functions can be performed depends on the presentation page and a specific function of the device.
[0061] FIGS. 6 to 8 illustrate processes performed according to a first embodiment of the present invention. Among the figures, FIG. 6 illustrates the process of determining a master device. First, all the controlled devices 110 to 160 notify the control point 190 that they have been connected to the home network by using the SSDP (S 601 ). Then, the control point 190 obtains device information and DRM information from the devices 110 to 160 (S 602 ) through a HTTP. Here, device information means general device information for use in UPnP, and DRM information means a device attribute and a device mode. The device attribute is a value for use in determining whether the controlled device can be operated as a master device in the domain. Further, the device mode is a value enabling determination on whether the device is currently operated as a master, slave or guest. All the controlled devices are initially set as guests. Thereafter, if the devices are set as a master or slaves, the value of the device mode may be changed.
[0062] It is determined from the device mode of the DRM information whether there is a controlled device operating as a master. If there is no device operating as a master, one of the controlled devices that can be operated as a master device, is selected (S 603 ). Setting a device as a master in such a manner is accomplished by means of user selection through a user interface of the control point 190 . An example of the user interface is shown in FIG. 9 a. In the user interface, there are shown “main nexus” and “sub nexus” which are operable as a master and currently set as guests. In order to select a master, a user simply marks a check for one of the devices that the user desires to designate as the master. In the present example, controlled device 1 110 is selected as the master.
[0063] Next, the control point 190 obtains manager authentication information of controlled device 1 110 set as the master through SOAP. Such manager authentication information may be retrieved from a smart card of the master and is required for a procedure of confirming whether the user that has selected the master is a legitimate manager. The control point 190 performs manager authentication by outputting a user interface using the manager authentication information and receiving a manager's ID and password from the user (S 605 ). FIG. 9 b shows one example of such a user interface.
[0064] After the manager authentication, the control point 190 sets controlled device 1 110 as a domain master and then provides controlled device 1 110 with a list of devices that the control point 190 possesses (S 606 ). Thereafter, the device mode value of controlled device 1 110 becomes “master.” Controlled device 1 110 set as the master initially creates a new domain with only the device itself as a member (S 607 ).
[0065] FIG. 7 illustrates a device-authenticating process performed subsequent to the process illustrated in FIG. 6 according to the first embodiment of the present invention. First, the domain master 110 receives a new SIB through an external server in such a manner illustrated in FIG. 3 (S 611 ). The control point 190 then delivers URL information with the SIB stored therein to the remaining controlled devices 120 to 160 by using SOAP (S 612 ). The remaining controlled devices 120 to 160 obtain the SIB present in the URL through HTTP (S 613 ). Then, the controlled devices extract secret values using the obtained SIB, and create certificates using the secret values and their own IDs and public keys (S 614 ). These certificates are used for discriminating illegal devices from legitimate devices. For example, if an authentication policy in which only devices produced by specific manufacturers are approved as legitimate devices is enforced, devices produced by other manufacturers except the specific manufacturers would be treated as illegal devices.
[0066] Thereafter, when the control point 190 sends URL information containing the certificates to the master device 110 through SOAP (S 615 ), the master device 110 obtains the certificates, device IDs and public keys from the remaining controlled devices 120 to 160 by using HTTP (S 615 ). Further, the master device 110 verifies the obtained certificates and prepares a list of authenticated devices (S 617 ). Devices classified into illegal devices through certificate verification are subsequently excluded from the domain, and there is no possibility for them to be designated as slave devices.
[0067] FIG. 8 illustrates the process of determining a slave device that is performed subsequent to the process illustrated in FIG. 7 according to the first embodiment of the present invention. First, the control point 190 verifies domain attributes for the devices 120 to 140 approved as legitimate devices according to the results of the certificate verification by using SOAP (S 621 ). Each domain attribute may include a domain key, the names of devices belonging to a domain, the number of devices belonging to the domain, and the like. If the devices have no domain attributes, the control point 190 displays a list of these devices through a user interface (S 622 ) and allows the user to select slave devices (S 623 ). FIG. 9 c illustrates an example of a user interface showing a list of the legitimate devices 120 to 140 . The user marks checks for devices that the user wishes to include in the domain among the listed devices to select slave devices. Contrary to the selection of the master, the user can select a plurality of devices as slave devices. Thereafter, in the same manner as the master-selecting process illustrated in FIG. 6 , manager authentication information is obtained (S 624 ) and the manager-authenticating process is performed (S 625 ).
[0068] Next, the control point 190 delivers a list of the slave devices selected among the listed devices to the master device 110 through SOAP (S 626 ), and sets the selected devices to the slave mode through SOAP (S 627 ). The devices that have been set to the slave mode have “slave” as their device mode values. Then, the master device 110 creates a domain ID and a domain key using the list of slave devices (S 628 ). The master device encrypts the domain ID and domain key using public keys for the slave devices (S 629 ).
[0069] Next, the control point 190 delivers the URL information containing the domain attribute value from the master device to the slave devices through SOAP (S 630 ). Then, the slave devices obtain the domain attribute present in the URL via HTTP (S 631 ). The domain attribute includes the domain key, the names of the devices belonging to the domain, the number of the devices belonging to the domain, and the like.
[0070] FIGS. 10 to 12 illustrate processes according to a second embodiment of the present invention. The second embodiment is different from the first embodiment in that important ones of the functions of the control point 190 are taken over by the master device 110 . The control point 190 deals with tasks related to user interfaces. As a result, the master device 110 has functions of a controlled device as well as functions of a control point except the residual function of the control point 190 . Accordingly, loads on the control point 190 are greatly reduced. Further, problems do not occur in view of security even though the control point 190 is an illegal device. Moreover, there are no problems even though the master device has no user interface.
[0071] Among these figures, FIG. 10 illustrates the process of determining a master device, wherein device 1 110 is operated only as a controlled device (CD). Therefore, this process is identical to the process of determining the master device illustrated in FIG. 6 according to the first embodiment. Thus, iterative description thereof will be omitted.
[0072] FIG. 11 illustrates a device-authenticating process performed subsequent to the process illustrated in FIG. 10 according to the second embodiment of the present invention. First, the control point 190 notifies the master device 110 through SOAP that the device-authenticating process starts (S 711 ). During this process, the master device is operated as a CD. Then, the master device 110 (operating as a CD) delivers the SIB directly to the remaining controlled devices 120 to 160 using SOAP. Then, the remaining controlled devices 120 to 160 extract secret values using the received SIB, and create certificates using the secrete values and their own device IDs and public keys (S 713 ).
[0073] Subsequently, the remaining controlled devices 120 to 160 deliver their certificates, device IDs and public keys directly to the master device 100 (operating as a control point) through SOAP (S 714 ). Then, the master device 110 verifies the received certificates and prepares a list of authentication devices (S 715 ). Devices classified as illegal devices through the certificate verification are subsequently excluded from the domain, and there is no possibility for them to be designated as slave devices. Then, the master device 110 (operating as a CD) notifies the control point 190 of device IDs of the verified devices by means of an event message by using GENA (S 716 ). Then, the control point 190 obtains the results of the verification of the devices from the master device 110 (operating as a CD) using SOAP (S 717 ), and then displays, through a user interface, the verification results on whether the devices are illegal or legitimate devices (S 718 ).
[0074] FIG. 12 illustrates the process of determining a slave device that is performed subsequent to the process illustrated in FIG. 11 according to the second embodiment of the present invention. First, the control point 190 verifies domain attributes for the devices 120 to 140 approved as legitimate devices according to the results of certificate verification by using SOAP (S 721 ). If the devices have no domain attributes, the control point 190 displays a list of these devices through a user interface (S 722 ), and allows the user to select slave devices (S 723 ). FIG. 9 c illustrates an example of the user interface showing a list of legitimate devices 120 to 140 . The user marks checks for devices that the user wishes to include in the domain among the listed devices to select slave devices. Thereafter, in the same manner as the master-selecting process illustrated in FIG. 6 , the manager authentication information is obtained (S 724 ) and the manager-authenticating process is performed (S 725 ).
[0075] Next, the control point 190 delivers a list of slave devices 120 to 140 selected among the listed devices to the master device 110 (operating as a CD) through SOAP (S 726 ). Then, the master device 110 creates a domain ID and a domain key using the list of slave devices (S 727 ). Then, the master device encrypts the domain ID and domain key using public keys for the slave devices (S 728 ). The master device 110 (operating as a control point) directly sets the selected devices to the slave mode through SOAP, and then delivers the domain attributes of the set devices (S 729 ).
[0076] According to the present invention, there are advantages in that it possible to construct a domain independent of the outside by using a public key-based architecture in which a user is directly involved in constructing the domain, and a domain key is created using a authentication list and a random number as input values and thus varies depending on changes in members belonging to the domain, thereby more safely limiting the use of content.
[0077] Further, according to the present invention, there is an advantage in that since a communication method implemented in UPnP can be used as it is in applying domain management techniques to a home network, it is not necessary to develop a new communication method among members in a domain. Further, the present invention has advantages in that devices included in a home network can be more easily authenticated, smooth incorporation into conventional networks can be made without depending on specific operating systems or physical media by using a standard Internet protocol, and compatibility with all devices supporting UPnP can be achieved.
[0078] Although the embodiments of the present invention have been described with reference to the accompanying drawings, it can be understood by those skilled in the art that the present invention can be implemented in other specific forms without modifying or changing the technical spirit and essential features thereof. Therefore, it should be understood that the aforementioned embodiments are not limitative but illustrative in all aspects. The scope of the present invention should be defined by the appended claims, and all changes or modifications made from the spirit and scope of the invention and equivalents thereof should be construed as falling within the scope of the invention. | A method of constructing a unique domain for preventing content from being illegally used by an unauthorized third person in a public key-based architecture and applying the constructed domain to a home network using universal plug and play (UPnP). The method of the present invention includes selecting one of controlled devices that are operable as a master device and determining the selected device as the master device; performing device authentication in such a manner that other controlled devices receive a secret information block from the determined master device and create certificates; and determining slave devices by selecting one or more devices among the authenticated controlled devices. | 7 |
TECHNICAL FIELD
[0001] The present invention relates to a method for satisfying performance requirements of a random access channel used by a mobile station for accessing a communication network accessible in a communication cell served by a radio base station, wherein said mobile station communicates on uplink and downlink channels. The invention further relates to a communication network node using said method.
BACKGROUND
[0002] The demand for wireless data services, such as text messaging (SMS), multi-media messaging (MMS), mobile video and IPTV, demanding higher bandwidth is growing quickly. The third generation partnership project (3GPP) is developing the third generation mobile systems based on evolved GSM core networks and the radio access technology UMTS terrestrial radio access (UTRA) and has come up with a new orthogonal frequency division multiple access (OFDMA) based technology through the long term evolution (LTE) work, which provides a very efficient wireless solution. The OFDMA based air interface is often referred to as the evolved UMTS terrestrial radio access network (E-UTRAN).
[0003] The architecture of the LTE system is shown in FIG. 1 . In LTE the downlink (DL) is based on orthogonal frequency division multiplexing (OFDM), while the uplink (UL) is based on a single carrier modulation method known as discrete Fourier transform spread OFDM (DFT-S-OFDM).
[0004] During initial access, a mobile station (MS) seeks access to the network in order to register and commence services. The random access (RA) serves as an uplink control procedure to enable the MS to access a communication network operated from a base station (BS) serving a communication cell. Since an initial access attempt cannot be scheduled by the network, the RA procedure is by definition contention based. Collisions may occur and an appropriate contention-resolution scheme needs to be implemented.
[0005] Including user data on the contention-based uplink is typically not spectrally efficient due to a need for guard periods and retransmissions. Therefore, for LTE it has been decided to separate a transmission of a random access burst (a preamble), the purpose of which is to obtain uplink synchronization, from a transmission of user data.
[0006] The LTE RA procedure serves two main purposes:
It lets the MS align its UL timing to that expected by the eNode B (see FIG. 1 ) in order to minimize interfering with other MSs transmissions. UL time alignment is a requirement in E-UTRAN before data transmissions may commence. It provides means for the MS to notify the network of its presence and enables the eNode B to give the MS initial access to the system.
[0009] In addition to the usage during initial access, the RA will also be used when the MS has lost the uplink synchronization or when the MS is in an idle or a low-power mode.
[0010] The basic RA procedure is a four-phase procedure, as outlined in FIG. 2 , and is as follows:
In phase 1, the MS 18 transmits a random access preamble (step 21 ), allowing the eNode B (BS) to estimate the timing of the MS. Uplink synchronization is necessary as the MS otherwise cannot transmit any uplink data; In phase 2, the network transmitting a timing advance command (step 22 ) to correct the uplink timing, based on the timing of preamble arrival in the first step. In addition to establishing uplink synchronization, phase 2 also assigns uplink resources and temporary identifier to the MS to be used in phase 3 of a random access procedure; Phase 3, consists of signalling from the MS 18 to the network (step 23 ) using the UL-SCH similar to normal scheduled data. A primary function of this message is to uniquely identify the MS 18 . The exact content of this signalling depends on the state of the MS 18 , e.g., whether it is previously known to the network or not; The final phase (phase 4), is responsible for contention resolution in case multiple MSs tried to access the system on the same resource.
[0015] For cases where the network knows, in advance, that a particular MS will perform a Random Access Procedure to acquire uplink synchronization, a contention-free variety of the Random Access Procedure has been agreed. This effectively makes it possible to skip the Contention Resolution process of Phases 3 and 4 for important cases such as arrival to target cell at handover (HO) and arrival of DL data.
[0016] Phase 1—Random Access Preamble
[0017] Prior to sending a preamble, the MS shall synchronize to the downlink transmissions and read the Broadcast Control Channel (BCCH). The BCCH will reveal where the RA time slots are located, which frequency bands may be used, the settings of the power control parameters, and which preambles (sequences) are available.
[0018] At the next RA slot, the MS will send the preamble. The preamble sequence implicitly includes a random ID, which identifies the MS. LTE provides for each cell 64 such random IDs and thus 64 preambles.
[0019] If multiple RA frequency bands have been defined, the MS randomly selects one of them. The group of sequences allocated to a cell is partitioned into two subgroups. By selecting a preamble sequence from a specific subgroup, the MS can give a single-bit indication of its resource requirement and/or link quality. The particular sequence used for the preamble is randomly selected within the desired subgroup. This sequence implicitly contains a random ID, which serves as an MS identifier.
[0020] The eNode B estimates the UL timing of the MS based on the timing of the received preamble.
[0021] Phase 2—Random Access Response
[0022] After the preamble transmission, the MS waits for an RA Response message on the DL-SCH, the DL assignment which is indicated on the L1/L2 control channel (DPCCH). The RA Response message is transmitted semi-synchronously (i.e. within a window) to the reception of the RA Preamble in order to allow the scheduler more flexibility. The RA Response contains:
the same random MS identity as present in the preamble; a time alignment message to provide the proper uplink timing to the MS; a temporary Radio Network Temporary Identifier (RNTI) which is unique for the particular RA resource (time, channel and preamble) used in Phase 1. For initial access, the temporary RNTI shall be used for Phases 3 and 4; a UL resource grant for transmission on UL-SCH in Phase 3.
[0027] If no RA Response message has been received after a certain time following the preamble transmission, the MS shall send a new preamble at the next RA time slot. It shall select new, random parameters for the preamble sequence and the non-synchronized RA frequency band. Furthermore, the MS will increase the power level of the preamble to obtain a power ramping procedure similar as used in WCDMA.
[0028] Phase 3—First Scheduled UL Transmission
[0029] In Phase 3, the MS provides the network with a unique identifier in the message it transmits on UL-SCH according to the grant contained in the RA Response. The type of MS identifier, e.g. C-RNTI, TMSI, IMSI or IMEI, depends on to which extent the MS is already known in the network.
[0030] In case of initial access, the message is an RRC Connection Request message. In case of non-initial access, i.e. when the MS is already RRC_CONNECTED, the MS identifier is the C-RNTI and is signalled by a MAC layer. The transmission uses HARQ.
Phase 4—Contention Resolution
[0031] The purpose of the fourth phase is to resolve contention. Note that, from the second step, multiple MSs performing simultaneously random access attempts using the same preamble listen to the same response message and therefore have the same temporary identifier. Hence, in the fourth phase, the eNode B echoes the MS identity provided by the MS in Phase 3. Only a terminal which finds a match between the identity received in the fourth step and the identity transmitted as part of the third step will declare the random access procedure successful. This terminal will also transmit a hybrid ARQ acknowledge in the uplink. For non-initial access, i.e. when the MS is already RRC_CONNECTED, the MS identity is reflected on the L1/L2 control channel. If the MS has not yet been assigned a C-RNTI, the temporary identity from the second step is promoted to the C-RNTI, otherwise the MS keeps its already assigned C-RNTI.
[0032] Terminals which do not find a match between the identity received in Phase 4 and the respective identity transmitted as part of Phase 3 are considered to have failed the random access procedure and need to restart the random access procedure with Phase 1; selecting new random parameters for the preamble sequence and the RA frequency band. No hybrid ARQ feedback is transmitted from these terminals.
[0033] Contention-Free Random Access Procedure
[0034] For cases where the network knows, in advance, that a particular MS will perform a Random Access Procedure to acquire uplink synchronization, a dedicated preamble is reserved and assigned to the MS under consideration. Dedicated Preamble assignment for HO is handled by RRC, whereas preamble assignment for DL data arrival is handled by MAC. When the MS transmits the dedicated preamble in Phase 1, the network knows to which MS this preamble was assigned and can already at the time of detection of this preamble determine the identity of the MS. Thus no contention resolution is needed and the delay before data transmission can be resumed is reduced.
[0035] Random Access Back-Off Procedure
[0036] For the event of Random Access overload, a Random Access Back-Off procedure is supported. This procedure prevents immediate new Random Access attempts which would only worsen a collision situation.
[0037] Random Access Channel Physical Resource
[0038] A single RA opportunity consists of a time slot and a fixed bandwidth. The RA time slot length T RA shall accommodate the preamble sent by the MS and the required guard period (GP) to take into account the unknown uplink timing. FIG. 3 shows the access burst timing for two MSs 18 a and 18 b, where the preamble is denoted 31 and the guard period (GP) is denoted 32 . The timing misalignment amounts to 6.7 μs/km. 3GPP has decided for a minimum T RA of 1 ms. Here the preamble length is then 800 μs plus a cyclic prefix of around 102.5 μs. A guard time of 97.5 μs suffices for cell radii up to 15 km. Larger guard periods and cyclic prefix are needed to accommodate timing uncertainties from cells larger than 15 km. Such large cells may also require longer preambles to increase the received energy. In order to support RA under various cell conditions RAN 1 has defined additionally 3 RA preamble formats which require a T RA of 2 ms or even 3 ms. These larger slots are created by the eNode B by not scheduling traffic in the consecutive sub-frame(s). Those extended preambles contain repetitions of the 800 μs long part and/or a longer cyclic prefix.
[0039] For TDD an additional “short” RA is defined. The short RA preamble only spans 133 μs. Because of this very short duration the preamble will most likely not contain a cyclic prefix but a technique called overlap-and-add will be used to enable frequency-domain processing. At present many details regarding applicability and performance of this short RA are still open.
[0040] According to 3GPP, the bandwidth of a RA opportunity is 1.08 MHz (6 RB). The effective bandwidth utilized by the RA preamble is 1.05 MHz leaving small spectral guard bands on each side. This is necessary since RA and regular uplink data are separated in frequency-domain but are not completely orthogonal.
[0041] For FDD systems, RA opportunities do not occur simultaneously in different frequency bands but are separated in time. This spreads processing load out in the RA receiver. 3GPP defines RA configurations determining how often RA opportunities occur. In total 16 such configurations are defined, ranging from one RA opportunity every 20 ms (very low RA load) to one every 1 ms (very high RA load).
[0042] In TDD not all sub-frames are DL sub-frames reducing sub-frames that can be allocated to RA. To provide also in TDD configurations for high RA loads multiple RA opportunities can be scheduled in a single sub-frame.
[0043] In order to compensate for the rather low frequency diversity obtained within 1.05 MHz the RA opportunity hops in frequency-domain. For FDD RA opportunities are restricted to the outermost 6 RBs of the physical uplink shared channel at each band edge.
[0044] The TDMA/FDMA structure of the RA opportunities in FDD is visualized in FIG. 4 where the time and frequency configuration of the PRACH, PUSCH, and PUCCH in the LTE uplink is shown. In this example, three RA opportunities with 1 ms length exist in each frame. Here only one 1.08 MHz band is allocated to RA at each time whereas several bands are possible in case of TDD. The RA opportunities always occur at the band edges of the physical uplink shared channel directly adjacent to the physical uplink control channel.
[0045] Preamble Format
[0046] FIGS. 5 a to 5 d shows random access preambles, wherein FIG. 5 a shows the detailed timing of the basic random-access preamble 31 . The preamble 31 is prefixed with a cyclic prefix (CP) 51 to enable simple frequency domain processing. Its length is in the order of T GP +T DS =97.5+5 μs=102.5 μs, where T DS corresponds to the maximum delay spread and T GP corresponds to the maximum round trip time. The CP 51 insures that the received signal is always circular (after removing the CP in the RA receiver) and thus can be processed by FFTs. Therefore, the “active” random-access preamble duration is 1000 μs−2·T GP −T DS =800 μs. The RA subcarrier spacing is 1/800 μs=1250 Hz.
[0047] FIG. 5 b to FIG. 5 d show the extended preamble formats. The format of FIG. 5 b has an extended CP 51 and is suited for cell radii up to approximately 100 km. However, since no repetition occurs this format is only suited for environments with good propagation conditions. The format of FIG. 5 c contains a repeated main preamble 31 and a cyclic prefix 51 of approximately 200 μs. With an RA opportunity length of 2 ms the remaining guard period is also approximately 200 μs. This format supports cell radii of up to approximately 30 km. The format of FIG. 5 d also contains a repeated main preamble 31 and an extended CP 51 . Using an RA opportunity length of 3 ms this format supports cell radii of up to approximately 100 km. In opposite to format of FIG. 5 b the format of FIG. 5 d contains a repeated preamble 31 and is therefore better suited for environments with bad propagation conditions.
[0048] Zadoff-Chu Sequences
[0049] The requirements on the sequence comprising the preamble are two-fold: good auto-correlation function (ACF) properties and good cross-correlation function (CCF) properties. A sequence that has ideal (periodic) ACF and CCF properties is the Zadoff-Chu sequence. The periodic ACF of Zadoff-Chu sequence is only non-zero at time-lag zero (and periodic extensions) and the magnitude of the CCF is equal to the square-root of the sequence length N. Due to special properties of Zadoff-Chu sequences the number of sequences is maximized if N is chosen prime. This together with the requirement that the effective RA bandwidth N·1250 Hz should fit into 1.05 MHz leads to N=839.
[0050] A Zadoff-Chu sequence of length N can be expressed, in the frequency domain, as
[0000]
X
ZC
(
u
)
(
k
)
=
-
j
π
u
k
·
(
k
+
1
)
N
(
1
)
[0051] where u is the index of the Zadoff-Chu sequence within the set of Zadoff-Chu sequences of length N. Out of one Zadoff-Chu sequence—in the following also denoted root sequence—multiple preamble sequences can be derived by cyclic shifting. Due to the ideal ACF of Zadoff-Chu sequence multiple mutually orthogonal sequences can be derived from a single root sequence by cyclic shifting one root sequence multiple times the maximum allowed round trip time plus delay spread in time-domain. The correlation of such a cyclic shifted sequence and the underlying root sequence has its peak no longer at zero but at the cyclic shift. If the received signal has now a valid round trip delay—i.e. not larger than the maximum assumed round trip time—the correlation peak occurs at the cyclic shift plus the round trip delay which is still in the correct correlation zone. FIG. 6 a shows the correlation peak when the MS is close to Node B and FIG. 6 b shows the correlation peak when the MS is almost at the cell border. In FIGS. 6 a and 6 b , 65 is the time delay which indicates the round trip delay and the arrows indicates the zones 0 - 5 indicating transmitted sequences. For small cells up to 1.5 km radii all 64 preambles can be derived from a single root sequence and are therefore orthogonal to each other. In larger cells not all preambles can be derived from a single root sequence and multiple root sequences must be allocated to a cell. Preambles derived from different root sequences are not orthogonal to each other.
[0052] One disadvantage of Zadoff-Chu sequences is their behaviour at high frequency offsets. A frequency-offset creates an additional correlation peak in time-domain. A frequency offset has to be considered high if it becomes substantial relative to the RA sub-carrier spacing of 1250 Hz, e.g. from 400 Hz upwards. The offset of the second correlation peak relative to the main peak depends on the root sequence. An offset smaller than T CS may lead to wrong timing estimates, whereas values larger than T CS increase the false alarm rate. In order to cope with this problem LTE has a high-speed mode (or better high frequency offset mode) which disables certain cyclic shift values and root sequences so that transmitted preamble and round trip time can uniquely be identified. Additionally a special receiver combining both correlation peaks is required. For cells larger than approximately 35 km no set of 64 preambles exists that allows unique identification of transmitted preamble and estimation of propagation delay, i.e. cells larger than 35 km cannot be supported in high speed mode.
[0053] Preamble Detection
[0054] A receiver at the eNodeB correlates the received signal with all the root sequences (Zadoff-Chu sequences) allocated to the eNodeB, see FIG. 7 If the correlation (height of the correlation peak) due to a preamble is higher than the detection threshold, then the preamble is detected. However, if the correlation is lower than the detection threshold then the preamble is not detected. We say in the latter case that we have a detection miss. The detection miss probability is the probability that the correlation between the root sequence and the received signal is less than the detection threshold when in fact a preamble was sent (i.e., we have a miss detection).
[0055] Correlation peaks may also occur due to noise or cross-interference from preambles derived from a different root sequence. A correlation due to noise or interference may become higher than the detection threshold, especially, if the detection threshold is set too low. In this case, no preamble is sent, however, the eNodeB concludes a preamble detection since the peak is above the threshold. We say that we have a false detection. The probability that a correlation peak due to noise or interference is higher than the detection threshold, i.e. we have a false detection, is called the false detection probability.
[0056] The correlation may be interpreted as the received power of a transmitted preamble. Hence, the detection performance is related to the preamble Signal power to Interference and Noise power Ratio, SINR. The notation of correlation and received power can be used interchangeably, and the cause of a missed detection can therefore be said to be due to insufficient correlation, or to insufficient received power.
[0057] From a user perspective, it is irrelevant if the random access attempt failed due to a miss detection or contention. Instead, it is the access probability that matters, which is the probability that a sent preamble is correctly detected without contention.
[0058] RACH Power Control
[0059] Power control has been agreed for RACH in LTE:
[0000] P RACH ( N )=min{ P MAX , P O — RACH +PL +( N− 1)Δ RACH +Δ Preamble }.
where P RACH is the preamble transmit power, N=1, 2, 3, . . . is the RACH attempt number, P MAX is the maximum MS power, P 0 — RACH is a 4-bit cell specific target received power signaled via BCCH with a granularity of 2 dB (difference in maximum and minimum P 0 — RACH is 30 dB), PL is the path loss estimated by the MS, Δ RACH is the power ramping step signaled via BCCH and represented by 2 bits (4 levels) with a granularity of 2 dB, Δ Preamble is a preamble-based offset (format 0-3), see the Preamble format paragraph above.
[0068] Note that RACH attempts N=2, 3, 4, . . . includes retransmissions where:
no RA Response message has been received by the MS (see FIG. 2 ), the RA Response message is intended for another preamble (MS), the contention resolution has failed and the MS has to try random access again.
[0072] In essence, the MS will increase its transmission power until network access is granted. There is typically an upper bound on the number of retransmissions and, thus, number of power increases.
[0073] Drawbacks of Existing Solutions
[0074] One of the fundamental problems related to RACH optimization is to adjust a set of RA parameters, e.g., desired target receive power P 0 — RACH , such that random access performance requirements are satisfied, and excessive interference generated by RACH is avoided.
[0075] The setting of RA parameters depends on a multitude of factors including, chosen root sequence (in general the preambles allocated to a cell), whether the cell is in high-speed mode or not, interference from neighboring cells, cell size etc.
[0076] Typically a wide range of RA parameters are simulated and those settings that satisfy given requirements and that minimize the interference are chosen. This approach is, however, not satisfactory due to the several reasons, e.g.:
There is a need to perform extensive simulation test and field trials, which is very costly. Simulations may not be accurate, hence, the derived set of parameters may be sub-optimal. RA parameters need to be reconfigured if network characteristics changes, e.g., the inference levels increases, or preambles need to be changed, MSs start moving in a higher speed in a cell (due to for example a high way built). Finding good set of parameter using simulation or field trials is a slow process and not sufficiently responsive to changes in network, hence, it may take a while before RACH is optimized. One object of the present invention aims at alleviating the problems with today's solutions.
[0082] Patent documents related to this invention, such as U.S. Pat. No. 7,072,327 and U.S. Pat. No. 6,487,420, describe automated tuning of RA, however, none of them addresses E-UTRAN and Zadoff-Chu based random access, which is used in E-UTRAN.
SUMMARY
[0083] Accordingly, one object of the present invention is to provide an improved method and communication network node for enabling auto-tuning of random access procedures when mobile stations are accessing a communication network system comprising radio base stations each serving at least one cell and with which said mobile stations are communicating on uplink and downlink channels. The invention is also directed to a mobile station using said innovative communicating network system.
[0084] According to a first aspect of the present invention this objective is achieved through a method as defined in the characterising portion of claim 1 , which specifies satisfying random access attempt success requirements during said random access procedures, wherein the method performs the steps of: estimating quantities related to random access attempt success statistics, tuning random access parameters such that said estimated quantities related to random access attempt success statistics satisfies predetermined requirements, and that an excessive interference caused by mobile stations attempting random access in said communication cell is avoided.
[0085] The quantities related to random access attempt success statistics comprise detection miss probability, false detection probability and access probability. As an alternative said quantities related to random access attempt success statistics comprise detection miss probability and access probability for a specific number of transmission attempt. Said sampling period is fixed or varying according to the amount of data needed to estimate said quantities.
[0086] According to a second aspect of the present invention this objective is achieved through an arrangement as defined in the characterising portion of independent device claim 15 , which specifies a communication network node for enabling auto-tuning of a random access channel used by mobile stations (MS) when requesting access to a communication network system in a communication cell served by a radio base station (BS), wherein said mobile station communicates on uplink and downlink channels. The base station subsystem, comprises a Random Access (RA) optimizer for tuning random access parameters such that random access attempt success statistics satisfy predetermined requirements, and for tuning random access parameters such that excessive interference caused by mobile stations (MS) attempting random access in said communication cell is avoided.
[0087] Further embodiments are listed in the dependent claims.
[0088] Automatically optimizing RA parameters such that random access attempt success statistics satisfy given requirements, and extensive interference caused by RACH is avoided leads to lower costs for the operators in planning and tuning RACH, as well as improved system performance.
[0089] Some of the advantages offered by this invention are as follows:
Very little or no human intervention is required when optimizing RA parameters, resulting in a reduction of operational expenditure (OPEX). Manual effort in setting and tuning RA parameters decreases. The method presented is based on feedback information and, as such, the RA optimization process is responsive to changes in radio propagation conditions in the cell. Radio propagation models based on, e.g., topology, are not needed, since the invention relies on the feedback information from the MSs and BS. The interference generated by RACH is minimized, thus, increasing the SNR (Signal Noice Ratio) and performance of the radio bearers in the cell where RA optimization is executed, as well as neighboring cells. The detection miss and access probabilities are maintained at acceptable levels, resulting in fewer preamble retransmissions by the MSs and acceptable access delays. The false detection probability is maintained at acceptable levels, reducing the signaling over the air and, thus, releasing resources for, e.g., user data.
[0097] Still 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
[0098] In the drawings, wherein like reference characters denote similar elements throughout the several views:
[0099] FIG. 1 shows a communication network architecture according to the present invention.
[0100] FIG. 2 illustrates a random access procedure in case of initial access.
[0101] FIG. 3 shows an access burst timing for two user equipments.
[0102] FIG. 4 shows the time-frequency structure of non-synchronized RA for FDD.
[0103] FIG. 5 a shows the random-access preambles defined by 3GPP according to a first format.
[0104] FIG. 5 b shows the random-access preambles defined by 3GPP according to a second format.
[0105] FIG. 5 c shows the random-access preambles defined by 3GPP according to a third format.
[0106] FIG. 5 d shows the random-access preambles defined by 3GPP according to a fourth format.
[0107] FIG. 6 a shows the correlation peak when the MS is close to Node B.
[0108] FIG. 6 b shows the correlation peak when the MS is almost at the cell border.
[0109] FIG. 7 illustrates correlation between received signal and root sequences.
[0110] FIG. 8 depicts a system view of the constituents of an example of the arrangement according to the invention.
[0111] FIGS. 9 a - 9 d illustrate cases of the interaction between DMPC and RIC.
[0112] FIG. 10 outlines a first embodiment of detection miss probability control.
[0113] FIG. 11 shows cases with detections and detection misses.
[0114] FIG. 12 outlines a second embodiment of detection miss probability control.
[0115] FIGS. 13 a and 13 b illustrate examples of estimation of Received Power First Attempt (RFPA).
[0116] FIG. 14 shows a curve disclosing the cumulative distribution of the estimated received power of the first RFPA.
[0117] FIG. 15 shows the amplitude of correlation peaks caused by noise.
[0118] FIG. 16 is a curve showing the probability of a correlation peak due to noise.
[0119] FIG. 17 shows the RIC loop.
[0120] FIG. 18 shows correlations in a first mode of the P f -estimator
[0121] FIG. 19 illustrates a second mode of the P f -estimator.
[0122] FIG. 20 shows in:
[0123] a) setting the detection threshold D according to the distribution of the correlation peaks.
[0124] b) the noise distribution may be separated from the preamble distribution allowing the noise distribution to be estimated.
[0125] c) the noise distribution being estimated using any knowledge available regarding the noise distribution.
[0126] FIG. 21 shows a diagramme of a combined DMPC and RIC.
DETAILED DESCRIPTION
[0127] A communication system, such as a Long Term Evolution (LTE) system is shown in FIG. 1 , including a Radio Access Network (RAN), comprising at least one Radio Base Station (RBS) (or eNode B) BSa, BSb and BSc. The eNode Bs are connected over an interface such as the S1-interface 17 to at least one server gateway and mobility management entity node (S-GW/MME) 10 a and 10 b. The S-GW/MME node handles control signalling for instance for mobility, and is connected to external networks (not shown in FIG. 1 ) such as the Public Switched Telephone Network (PSTN) or the Integrated Services Digital Network (ISDN), and/or a connectionless external network as the Internet.
[0128] The RAN provides communication and control for a plurality of user equipments (MS) 18 (only one shown in FIG. 1 ) and each RBS BSa-BSc is serving at least one cell 19 through and in which the MSs 18 are moving. The RBSs BSa-BSc are communicating with each other over a communication interface 16 , such as X2. The MSs each uses downlink (DL) channels 12 and uplink (UL) channels 13 to communicate with at least one RBS over a radio or air interface.
[0129] According to a preferred embodiment of the present invention, the communication system is herein described as an LTE system. The skilled person, however, realizes that the inventive method and arrangement work very well on other communications systems as well. User equipments are herein referred to as mobile stations such as mobile telephones (“cellular” telephones) and laptops with mobile termination and thus can be, for example, portable, pocket, hand-held, computer-included or car-mounted mobile devices which communicate voice and/or data with the RAN.
[0130] Detection Miss Probability
[0131] The following definition of the detection miss probability of order C, P m (C) is introduced, wherein
[0000] P m ( C )= P ( N>C )=1− P ( N≦C )
[0132] Where N denotes the number of transmission attempts required for the preamble to be detected. The probability P m (C) is, thus, the probability that the MS needs more than C transmission attempts. It is natural to describe the RACH performance requirements in terms of P m (C). For example, the requirements could relate to two different orders of C:
1. The probability that the first transmission attempt is unsuccessful should be at most R m (1), e.g. 50%.
[0000] P m (1)≦ R m (1)=0.50
2. The probability that the detection is still unsuccessful after C 2 attempts should be at most R m (C 2 ), e.g. 5%.
[0000] P m ( C 2 )≦ R m ( C 2 )=0.05
[0135] The values and orders could of course be changed arbitrarily. In general, any number of orders may be used, e.g. the requirements may relate to four different orders, where the probability that detection is unsuccessful after C 1 , C 2 , C 3 , and C 4 transmissions should be at most R m (C 1 ), R m (C 2 ), R m (C 3 ) and R m (C 4 ), respectively.
[0136] Access Probability
[0137] The access probability after attempt C, P a (C), is defined as the probability that the C th preamble transmission attempt or earlier is successful and contention free. The probability P a (C) is, thus, the probability that the MS needs at most C preamble transmission attempts for obtaining access. Similar to detection miss probability, it is natural to describe the RACH performance requirements in terms of P a (C). For example, the requirements could relate to two different orders of C:
1. The probability that the first preamble transmission attempt is successful and contention free should be at least R a (1), e.g. 50%.
[0000] P a (1)≧ R a (1)=0.50
2. The probability that C 2 preamble transmission attempts or less are needed for obtaining access is at least R a C 2 ), e.g. 99%.
[0000] P a ( C 2 )≧ R a ( C 2 )=0.99
[0140] The values and orders could of course be changed arbitrarily. In general, any number of orders may be used, e.g. the requirements may relate to four different orders, where the probability that access is granted after C 1 , C 2 , C 3 , and C 4 transmissions should be at least R a (C 1 ), R a (C 2 ), R a (C 3 ) and R a (C 4 ), respectively.
[0141] Similarly, the inaccess probability P ia (C) is defined as
[0000] P ia ( C )=1− P a ( C ).
[0142] False Detection Probability
[0143] The false detection probability P f should be less or equal to R f , i.e. P f ≦R f .
[0144] Solution Overview
[0145] A solution according to the invention is an RA Optimizer consisting of two parts, namely (i) Detection Miss Probability Control (DMPC) and (ii) RACH Interference Control (RIC), see FIG. 8 . A measurement unit gathers BS measurements and MS reports, and outputs measurements to the RA Optimizer consisting of DMPC and RIC.
[0146] A similar solution based on Access Probability Control (APC) is obtained by reusing the same structure as DMPC, but using inaccess probability estimates (P ia ) instead of detection miss probability estimates (detection miss ratios). Moreover, an RA optimizer as a combination of APC and RIC can be designed, similar to the RA optimizer consisting of DMPC and RIC.
[0147] Throughout this invention, we let RA parameters refer to all parameters involved in RA at the BS and the MS, including but not limited to, RACH power control parameters, the RACH configuration, RACH persistence parameters, and RACH format.
[0148] Let a preamble correlation peak be a correlation peak due to a preamble sent by an MS. The set of preamble correlation peaks is, thus, a subset of all correlation peaks observed at the BS. DMPC alters the distribution of the preamble correlation peaks such that the detection miss probability equals a given requirement. The distribution of the preamble correlation peaks is modified by for example altering the mean amplitude of the preamble correlations. The detection miss probability or the portion of the preamble correlations that fall below the detection threshold, decreases as the mean amplitude of the preamble correlations increases and vice versa. In general, however, DMPC changes the distribution of the preamble correlation peaks by adjusting a multitude of RA parameters.
[0149] The second component of the RA Optimizer is RIC which aims at minimizing the interference caused by random access. This is done by decreasing the detection threshold as much as possible still satisfying requirements on false detection probability.
[0150] The results of the RA Optimizer are forwarded to the RA unit, which implements the RA functionality, e.g., broadcasting RA information to MSs, receiving and processing preambles sent by MSs, computing timing advance, and executing collision resolution. It should be clear to anyone skilled in the art what the functionality of the RA unit comprises. The input to the RA unit comprises RA parameters, some of which are then broadcasted. This is followed by a new round of measurement processing, execution of DMPC and RIC and so on.
[0151] An example is given below. This is followed by the description of DMPC and the RIC, and finally how DMPC and RIC are combined.
[0152] Example supported by FIG. 8 illustrating the main aspects of the invention:
[0153] Let us start with a situation where the RA parameters in a cell are poorly tuned, resulting in a relatively high detection miss probability and/or high interference caused by RACH. We will see, throughout this example, how the detection miss probability and the RACH generated interference may be decreased.
[0154] Consider a case a), FIG. 9 a , where the MSs send preambles with a too low power. This results in a detection miss probability greater than the given requirement, resulting in DMPC to tune RA such that the detection miss probability is decreased. Effectively, the DMPC tunes those RA parameters that affect the distribution of the preamble correlation peaks and, thus, the detection miss probability. By for example increasing, in a case b), the desired target receive power P 0 — RACH , MSs send preambles with a higher power, thus, increasing the correlation and the probability of detecting a preamble, as shown in FIG. 9 b.
[0155] At this point we have satisfied the detection miss probability requirement. However, the interference caused by RACH is overly high. As noted in case b) preamble correlation peaks are significantly higher than peaks due to noise and, as such, the detection threshold may be lowered using RIC, as shown in case c) illustrated in FIG. 9 c . This is then followed by one or several DMPC execution(s) resulting in a change in the preamble distribution, see FIG. 9 d representing case d). One of the results of DMPC is that MSs will transmit preambles with lower power and/or that the MSs will send fewer preamble retransmissions and, consequently, the interference generated by MSs performing random access is decreased.
[0156] In conclusion, RA parameters are tuned in order to meet detection miss probability requirements and to lower the interference caused by MSs performing random access.
[0157] Detection Miss Probability Control
[0158] A First Embodiment of Detection Miss Probability Control
[0159] In the following we sometimes drop the notation C when relating to P m (C) and R m (C). The general approach is presented in FIG. 10 . It may not be possible to accurately determine P m (C) and in general we resort to estimations of P m (C), which we hereafter denote with E m (C). The output of the P m -Estimator is together with R m fed into a controller (referred to as the M-Controller), which alters necessary RA parameters in order for E m to equal R m . The SINR (Signal to Interference Noise Ratio) of the received preambles may be used by the M-Controller in order to react faster to changes in interference.
[0160] The output of the M-Controller are then broadcasted to the MS(s) in the area covered by the BS. MSs receive the broadcasted RA information and adhere to updates of the RA parameters, e.g., RACH power control parameters and RACH persistence parameters. MSs may send RA-specific reports to the BS in order to aid P m estimation.
[0161] The M-Controller forces E m (C) to converge to R m (C) or to the vicinity of R m (C). This is done by adjusting RA parameters and thereby altering the distribution of the preamble correlation peaks such that E m (C) satisfies R m (C).
[0162] The P m -Estimator
[0163] First Embodiment of the P m -Estimator
[0164] FIG. 11 shows four different cases of multiple MSs performing random access. Case a) shows that different RA slot and preambles are used and we have good SNR resulting in a detection of the preamble. Case b) shows that different RA slot and preambles are used and we have poor SNR resulting in a detection miss. Case c) shows that the same RA slot and preamble is used and some preambles have good SNR while other have poor SNR, resulting in a preamble detection. Case d) shows that the same RA slot and preamble are used and we have poor SNR resulting in a detection miss. Cases a) and c) will result in a preamble detection and the BS sending an RA Response message to the MS(s). Cases b) and d) will result in a detection miss and, consequently, the BS will not send a RA Response message to the MS(s). Due to the lack of an RA response message from the BS (cases b) and d)), the MS(s) will retransmit the preamble using a higher transmission power.
[0165] The MS stores information related to preamble transmissions and reports this to the BS once the MS is granted access to the network, i.e., the last step of the RA procedure has been successfully executed. Let i denote a successfully executed RA starting with the initial preamble transmission and ending with the network access grant (involving several potential preamble retransmissions and contention resolution failures). Let N hd i be the number of transmission attempts during RA i.
[0166] By gathering the reported N i over some time, it is possible to estimate the detection miss probability P m (C) for a certain attempt number C. This can be done in a numerous different ways, e.g., by forming a histogram over the reported N i .
[0167] A core of the first embodiment is a method in a communication system comprising of:
gathering and processing measurements from mobile stations and/or base station, where the measurements consist of a number of preamble transmission attempts reported by mobile stations. tuning of RA parameters based on these measurements such that the preamble detection miss probability of mobile stations performing RA satisfies the given requirements, where the tuned RA parameters comprise RA parameters that affect the distribution of the preamble correlation.
[0170] A Second Embodiment of Detection Miss Probability Control.
[0171] The outline of the second embodiment is illustrated in FIG. 12 and is further described here.
[0172] The situation after a successful detection is illustrated by FIG. 13 a . Let i denote a successfully executed RA starting with the initial preamble transmission and ending with the network access grant (involving several potential preamble retransmissions and contention resolution failures). When the MS has reported the needed number of transmission attempts N i during RA i, it is possible to calculate the corresponding received power for a first transmission attempt at exactly the same conditions, except at a (N i −1)Δ RACH dB lower transmission power. This is described by FIG. 13 b.
[0173] FIGS. 13 a and 13 b illustrate the estimation of the Received Power First Attempt (RPFA).
[0174] a) The situation after successful detection—the received power of the preamble sequence exceeds the detection threshold.
[0175] b) Using knowledge about the number of needed transmission attempts and the power ramping step, it is possible to estimate the power of the first preamble, RPFA.
[0176] Gathering RPFA as described in FIG. 13 for all MSs in a cell for a certain time enables estimation of the RPFA distribution for users in the cell coverage area. Such a distribution is depicted in FIG. 14 .
[0177] FIG. 14 diagrammatically shows a cumulative distribution of the estimated received power of the first transmission attempt, RPFA. Also indicated are the R m (1)- and R m (C 2 )-percentiles, denoted CDF RPFA (R m (1)) and CDF RPFA (R m (C 2 )), respectively.
[0178] The RPFA data has been gathered during a time with a particular setting of the detection threshold D, P 0 — RACH , and Δ RACH . This data will be used together with the requirements R m (1) and R m (C 2 ) to adjust P 0 — RACH , and Δ RACH .
[0179] P 0 — RACH adjustment based on current P 0 — RACH , detection threshold, R m (1) and observed RPFA distribution:
[0180] In essence, the ambition is that the detection threshold (in terms of received preamble power) should be same as the R m (1)-percentile of the RPFA data. This is the same as the first requirement would have been fulfilled during the time of observation.
[0181] Let D be the detection threshold. This could be described by the following adjustment mechanism,
[0000] P 0 — RACH,new =P 0 — RACH,current +( D−CDF RPFA ( R m (1))).
[0182] If the R m (1)-percentile of the received power CDF RPFA (R m (1)) is greater than the detection threshold D, then the new level of P 0 — RACH shall be lower than the current level. In contrast, if this percentile is less than the detection threshold, then the new level of P 0 — RACH shall be higher than the current level.
[0183] Recall from a previous section that the parameter P 0 — RACH is represented by 4-bits and can thus take 16 different values with a 2 dB difference between each value. In case P 0 — RACH,new falls between two such values, then we may use the closest upper value or use the closest value.
[0184] Δ RACH adjustment based on current P 0 — RACH , detection threshold, R m (1) and observed RPFA distribution:
[0185] The RPFA data describes the variations in a particular cell with respect to uplink and downlink gain imbalances, since the uplink preamble power is set by the MS based on downlink measurements of the path gain. It also contains variations due to interference variations, since spurious interference may cause preamble retransmissions, and the number of retransmission attempts N i , is used when calculating the RPFA. Some cells may have a large variation in RFPA, which means that the ramping step Δ RACH also needs to be large in order to keep the number of transmission attempts at a desired level. Conversely, cells with small variations needs a small ramping step Δ RACH , in order to meet the requirements.
[0186] The central requirement when determining the ramping step Δ RACH is the R m (C 2 ), which specifies the probability that the transmission is successful after at least C 2 transmissions. The transmission power will increase from the first attempt to attempt C 2 by the power (C 2 −1)Δ RACH . This means that Δ RACH should be large enough to make the received power after attempt C 2 to be greater than the detection threshold in all cases except R m (C 2 ). Thus, the ramping step can be calculated as
[0000] Δ RACH,new =( D−CDF RPFA ( R m ( C 2 )))/( C 2 −1).
[0187] The new value of Δ RACH increases as the difference between the detection threshold D and the R m (C 2 )-percentile of the received power CDF RPFA (R m (C 2 )) increases. The new value of the ramping step Δ RACH times the number of additional retransmissions (C 2 −1) must bring this percentile level beyond the detection threshold.
[0188] In case there are requirements for several orders defined, then we form the maximum over Δ RACH computations for each order, i.e.,
[0000]
Δ
RACH
,
new
=
max
(
(
D
-
CDF
RPFA
(
R
m
C
2
)
)
/
(
C
2
-
1
)
(
D
-
CDF
RPFA
(
R
m
C
3
)
)
/
(
C
3
-
1
)
(
D
-
CDF
RPFA
(
R
m
C
4
)
)
/
(
C
4
-
1
)
…
)
[0189] The new value of the ramping step Δ RACH times the number of additional retransmissions (C j −1), where j>2 must bring CDF RPFA (R m (C j )) beyond the detection threshold D.
[0190] Recall from a previous section that Δ RACH can take four different values where the difference between each value is 2 dB. In case the computed Δ RACH,new falls between two such values (e.g., 2 dB<Δ RACH,new =2.5 dB<4 dB) then we may choose the closest upper value (Δ RACH,new =4 dB) or the closest value (Δ RACH,new =2 dB).
[0191] Core of the Second Embodiment
[0192] In this embodiment, the adjustments of the detection threshold, the desired target received power P 0 — RACH and the ramping step Δ RACH are separated from each other. The detection threshold is assumed to be modified by any of the other suggestions presented in the present description. The following steps describe how observed data is used to adjust the desired target received power and the ramping step:
Use reports from the MS about needed transmission attempts and knowledge of the current ramping step to adjust the received power estimates to the corresponding received power for a first attempt. Gather data from all random accesses during a certain time to compile an estimate of the distribution of the received power, first attempt. Use the detection threshold level, current level of P 0 — RACH , the miss detection probability after one transmission attempt and the distribution of the received power first attempt to determine a new level of P 0 — RACH . From the distribution, extract the percentile corresponding to the required miss detection probability. If this percentile is greater than the detection threshold, then the new level of P 0 — RACH shall be lower than the current level. If this percentile is less than the detection threshold, then the new level of P 0 — RACH shall be higher than the current level. Use the detection threshold level, the miss detection probability after C 2 transmission attempt and the distribution of the received power first attempt to determine a new level of Δ RACH . From the distribution, extract the percentile corresponding to the required miss detection probability. The ramping step Δ RACH times the number of additional retransmissions (C 2 −1) must bring this percentile level beyond the detection threshold.
[0199] RACH Interference Control
[0200] The second component of this invention is the RIC, see FIG. 8 . The aim of RIC is to reduce the interference caused by RACH by altering the detection threshold as described in FIG. 9 . Assume the case where there are no preamble transmissions, i.e., the correlation peaks are due to noise solely. It may occur that the amplitude of one or several correlation peaks will be greater than the detection threshold, see FIG. 15 , which shows that the amplitude of the correlation peaks caused by noise may be greater than the detection threshold.
[0201] The probability of a correlation peak due to noise to be above the detection threshold is denoted by P f . The relationship between the detection threshold D and P f is given by
[0000] P f =0, D>D n
[0000] P f >0, D≦D n
[0202] where D n is the maximum correlation due to noise. In general, P f decreases as D increases as shown in FIG. 16 . The actual shape of the curve and the location of D n depends on, e.g., interference and noise levels in own and neighbouring cells.
[0203] It is desired to decrease the detection threshold as much as possible, since this will in combination with DMPC described in a previous section decrease the interference caused by RACH. Decreasing the detection threshold will, however, increase the false detection probability P f . In this invention it is assumed that a false detection probability of maximum R f >0 is tolerated.
[0204] The outline of the RIC method is given in FIG. 17 , which shows the RIC loop. The estimated false detection probability E f is fed back into a controller (referred to as the F-Controller), which, given requirements on the maximum false detection probability R f , computes a suitable detection threshold. The P f -estimator may also use reports from MSs to estimate P f .
[0205] The F-Controller alters the detection threshold D such that E f converges to R f or to the vicinity of R f . It should be obvious for anyone skilled in the art that a wide range of techniques can be used in the F-Controller.
[0206] Embodiments of the P f -Estimator are described below.
[0207] A First Embodiment of the P f -Estimator
[0208] In said first embodiment of the P f -Estimator the MSs report, when demanded by the BS, information regarding their random access attempts upon access to the network. For all the RA attempts from the first preamble until the network access is granted, an MS records the information needed to verify the validity of the correlation peak(s), generated by the preambles sent by the MS, in time and RA slot as observed at the BS. This includes but is not limited to (i) BS that the MS attempted access to, (ii) the RA slot ID (number) or the time interval, (iii) the preamble (root sequence and shift) used in each RA slot, and (iv) the timing advance received from the BS in the final and successful attempt. Here we assume that an MS has not changed its location considerably in the direction toward the BS, i.e., we assume that the round-trip time (and the timing advance) does not change significantly between the RA attempts (this may not be a valid assumption in a high-speed cell). The BS compares the correlation peaks above the detection threshold with those reconstructed using MS reports (discarding RA attempts with other BSs) and if a peak does not match that reported by all MSs, then that peak is found to be a false detection. This is illustrated in FIG. 18 .
[0209] FIG. 18 shows that the root sequence index is denoted with u and the shift is denoted with v (see a previous section). Four MSs have reported their random access attempts. MS 1 has reported use of preamble (u=16,v=2) and timing advance T 1 , MS 2 has reported use of preamble (u=16,v=55) and timing advance T 2 , MS 3 has reported use of preamble (u=16,v=55) and timing advance T 3 , and MS 4 has reported use of preamble (u=20,v=23) and timing advance T 4 . Two peaks in preambles (u=16,v=2) and (u=20,v=23) are greater than the detection threshold and are, thus, concluded to be preamble detections. These peaks do, however, not match the MS reports and are therefore classified as false detections.
[0210] A Second Embodiment of the P f -Estimator
[0211] In the second embodiment, the P f -Estimator uses the messages between the MSs and the BS to estimate the false detection probability. Recall from a previous section that upon detection of a preamble the BS sends an RA esponse message to the MS(s) that have sent the preamble. The MS(s) that have sent the preamble in the first step reply by sending a Connection Request (CR) message. If no Connection Request message is received at the BS after an RA Response message has been sent to the MS(s), then this may be due to a false detection. This is shown in 19 , where the RA Response messages and received Connection Request messages are fed into the P f -Estimator.
[0212] Let n RAR be the number of sent RA Response (RAR) messages and n CR be the number of times where at least one Connection Request messages is received from MS(s) after a RA Response message has been sent.
[0213] Below we give two alternative false detection probability estimators denoted by E f,1 and E f,2 . These two estimators differ in the type of input data that is needed to compute the estimate. The notation E f refers to either E f,1 or E f,2 throughout this invention.
[0214] The first estimator is given by
[0000]
E
f
(
1
)
=
1
-
n
CR
n
RAR
[0215] where E f,1 increases as the ratio n CR /n RAR decreases.
[0216] Messages between the MS and BS may be lost due to, e.g., high interference, and this gives an erroneous estimate of the false detection probability. Known message drop probabilities may be used to cancel out such bias. Let P RAR and P CR be the probability of dropping an RA Response message and a Connection Request message, respectively.
[0217] The second estimator is then given by,
[0000]
E
f
(
2
)
=
1
-
n
CR
n
RAR
(
1
-
P
CR
)
(
1
-
P
RAR
)
.
[0218] where E f,1 increases as the ratio n CR /n RAR decreases, P CR decreases, and P RAR decreases.
[0219] Note if ARQ or HARQ is used when transmitting the Connection Request then P CR is defined as the probability that the first transmission and all subsequent retransmissions are dropped.
[0220] A Third Embodiment of the Pf-Estimator
[0221] In the third embodiment, the distribution of the correlation peaks is used to derive E f . This corresponds to the approach presented in FIG. 17 , where no MS reports are used and the correlation peaks are input to the P f -Estimator. We want to set the detection threshold D such that the area under the noise distribution curve is less or equal to R f for correlations greater than D, see FIG. 20 a . This means that the noise distribution must be estimated or approximated.
[0222] The noise distribution may be separated from the preamble distribution by tuning RA parameters, e.g., setting P 0 — RACH to a high value, as shown in FIG. 20 b . Having the two distributions separated we are able to estimate the noise distribution. The estimation can also include any knowledge of the noise distribution derived theoretically, by simulation, or using real life data. The noise and the preamble distributions may have to be separated from time to time to estimate the noise distribution.
[0223] The noise distribution may also be estimated by utilizing knowledge of the noise distribution derived theoretically, by simulation, or using real life data, as shown in FIG. 20 c . An expected or predicted noise distribution may be used directly. Alternatively, the form or structure of an expected or predicted noise distribution may be fitted to observed data producing an estimate of the noise distribution. This does not require a separation of the noise and the preamble distribution.
[0224] Combining DMPC and RIC
[0225] DMPC and RIC must co-exist in order to minimize the interference caused by RACH and satisfy requirements on detection miss probability. DMPC and RIC are, however, coupled in that RIC alters the detection threshold D which in turn influences the detection miss probability as shown in FIG. 21 . For this reason there is a need of a coordinator that manages and controls the execution of the M-Controller and the F-Controller. For a given D it will take some time for E m to converge to R m . More specifically, the difference between E m and R m decreases each time the M-Controller executes. As such, the execution of the F-Controller should be followed by a series of executions of the M-Controller.
[0226] In a previous section it was mentioned that the preamble and the noise distributions may be separated in order to estimate the noise distribution. For this reason it is necessary to put the M-Controller in a mode resulting in a separation of the noise and the preamble distributions. In this mode, the P m -Estimator is turned off.
[0227] The sampling period T over which E m and E f are computed may be fixed or vary based on the amount of available data which is used to compute E m and E f .
[0228] Expressions such as “including”, “comprising”, “incorporating”, “consisting of”, “have”, “is” used to describe and claim the present invention are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural and vice versa.
[0229] Numerals included within parentheses in the accompanying claims are intended to assist understanding of the claims and should not be construed in any way to limit subject matter claimed by these claims.
[0230] Abbreviations:
[0231] APC Access Probability Controller
[0232] ARQ Automatic Repeat Request
[0233] BS Base Station
[0234] DL Downlink
[0235] DMPC Detection Miss Probability Controller
[0236] E-UTRAN Evolved Universal Terrestrial Radio Access Network
[0237] HO Hand Over
[0238] LTE Long Term Evolution
[0239] MS Mobile Station
[0240] RA Random Access
[0241] RACH Random Access Channel
[0242] RIC RACH Interference Control
[0243] UL Uplink
[0244] UL-SCH Uplink Shared Channel | A method and a communication network node for satisfying detection miss probability and false detection probability requirements in a random access channel used by mobile stations (MS) for accessing a communication network system comprising radio base stations (BS) each serving at least one cell ( 19 ). The method includes optimizing a random access channel, wherein the method performs estimating detection miss probability (P m) in said cell, tuning random access parameters such that said estimated detection miss probability satisfies predetermined requirements, estimating a false detection probability (P f) in said communication cell ( 19 ), tuning said random access parameters such that said estimated false detection probability satisfies predetermined requirements, and tuning said random access parameters such that an extensive interference caused by mobile stations attempting random access in said communication cell is avoided. | 7 |
BACKGROUND OF THE INVENTION
(a) Field of the Invention
The present invention relates to a door fixture with decorative panels. More particularly, the present invention relates to a door fixture comprising a handle attached to a door plate, a handle panel attached to the handle and a door plate panel attached to the door plate, the door plate being affixed to a door.
(b) Description of the Prior Art
Doors commonly include handles for ease of opening and closing. Door handles may be knobs, levers, or other graspable shapes. Escutcheon plates or door plates are often placed around door handles for ornamental or protective purposes. Individuals generally select door fixtures such as door handles and door plates for aesthetic purposes, such as matching an overall decorative scheme for a room or a building. However, some individuals may desire a greater ability to customize their door fixtures than simply selecting a color, material, and design style. A desirable feature for a door fixture would be a capability to customize its appearance to reflect the interests and aesthetic sensibilities of its owner.
SUMMARY OF THE INVENTION
The present invention is directed to a door fixture that includes decorative panels, allowing an individual to customize the appearance of the fixture. The door fixture system includes a door plate and an attached door handle. The door plate is attached to a door and includes an outer face opposite the door. The handle includes a graspable portion and a stem extending therefrom. The graspable portion of the handle has an outer face opposite the stem. A handle panel is attached to the outer face of the handle, and a door panel is attached to the outer face of the door plate. The door panel and door plate include complementary apertures adapted to serially receive a at least portion of the handle portion of the door handle. Preferably, the door panel and door plate each include decorative designs which provide complementary aesthetic meaning, such as, for example, a sports team logo on the handle panel and the team name on the door panel, or a race car number on the handle panel and a picture of the car on the door panel.
There are four common types of door handles: dummy, passage, privacy, and entrance. Dummy handles do not have latching or locking mechanisms and are often used for aesthetic purposes. Passage handles have latching devices but do not have locking mechanisms and are commonly used on hall or closet doors. Privacy handles have latching and locking mechanisms and are commonly used on bedroom and bathroom doors. Entrance handles are typically used on exterior doors and include privacy handles and keyed cylinders, i.e., deadbolts.
The present invention is compatible with all four types of door handles. Latching mechanisms are commonly engaged by rotating door handles and do not modify the outward appearance of door handles containing such. Handles with locking mechanisms include buttons, rotatable elements or other means for engaging the locking mechanism. These means for engaging the locking mechanism may be located on the outer face of the graspable portion of the handle or elsewhere on the handle or door plate. Preferably, the present invention is used with privacy and entrance handles that have means for engaging the locking mechanism positioned apart from the outer face of the graspable portion of the handle. As such, the decorative handle panel may cover substantially the entire outer face of the handle without need for a hole or passage for accessing the means for engaging the locking mechanism.
In one embodiment, the present invention is a door fixture for attachment to a door, the door fixture comprising: a door plate for mounting on a door, the door plate having a door plate inner face, a door plate outer face opposite the door plate inner face, and at least one side adjoining both the door plate inner face and the door plate outer face, wherein the door plate outer face includes a door plate aperture; a handle having a graspable portion and a stem extending therefrom, the graspable portion having a handle outer face opposite the stem; a handle panel attached to the handle outer face; and a door panel attached to the door plate outer face, the door panel including a door panel aperture aligned with the door plate aperture; wherein a portion of the stem extends serially through the door panel aperture into the door plate aperture, and wherein the handle panel and the door panel display related decorative designs.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the present invention will be had upon reference to the following description in conjunction with the accompanying drawing, wherein:
FIG. 1 depicts a front view of a door fixture;
FIG. 2 depicts an exploded side view of the door fixture;
FIG. 3 depicts an exploded top view of a door fixture, with the door plate and handle sectioned along line A-A of FIG. 1 ;
FIG. 4A depicts a cross-sectional view of the door plate along line A-A of FIG. 1 ;
FIG. 4B depicts a cross-sectional view of the door plate along line B-B of FIG. 1 ;
FIG. 5A depicts a front view of a door panel;
FIG. 5B depicts a side exploded view of the door panel;
FIG. 5C depicts a top exploded view of the door panel;
FIG. 5D depicts a side view of the door panel;
FIG. 6A depicts a front view of a handle panel;
FIG. 6B depicts a side view of the handle panel;
FIG. 6C depicts a side exploded view of the handle panel; and
FIG. 7 depicts a perspective exploded view of a second embodiment of a door fixture.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1-6 depict a door fixture 10 comprising a door plate 12 with attached door panel 14 and a door handle 16 with attached handle panel 18 . The handle 18 includes a graspable portion 20 and a handle outer face 22 opposite the door plate 12 . The handle outer face 22 is preferably a substantially flat surface. The handle 16 also includes a stem portion 24 extending opposite the handle outer face 22 in the direction of the door plate 12 . The handle panel 18 includes handle attachment means 26 for securing the handle panel 18 to the handle outer face 22 . In one embodiment, as shown in FIGS. 2 , 3 , 6 B, and 6 C the handle attachment means 26 is an elongated threaded rod 27 configured to be secured within a corresponding threaded handle bore 28 in the handle outer face 22 . In another embodiment, the handle attachment means 26 is an adhesive. The handle panel 18 covers at least a portion of the handle outer face 22 . Preferably, the handle panel 18 covers substantially the entire surface of the handle outer face 22 .
The door fixture 10 is configured to be installed on a door. As used herein, the term “inner” refers to an orientation in the direction of the surface of a door upon which the door fixture 10 is attached. The term “outer” refers to an orientation opposite that of “inner.” The term “height” refers to a distance perpendicular to the surface of the door. The terms “top” and “bottom” refer to the uppermost and lowermost parts of an object, from the view of an observer facing the door fixture 10 as installed.
The door plate 12 is designed to be mounted on a door and includes a plate outer face 30 , a plate inner face 32 opposite the plate outer face 30 , and at least one side 34 contiguous to both the plate outer face 30 and plate inner face 32 . The door plate 12 includes plate attachment means 36 for securing the door panel 14 to the plate outer face 30 . In one embodiment, the plate attachment means 36 is an adhesive. In another embodiment, as shown in FIGS. 2 , 3 , 4 A and 4 B, the plate attachment means 36 is a pair of upside-down “L-shaped” side support rails 38 extending perpendicular from the sides of the plate outer face 30 then angled parallel to the plate outer face 30 . The plate attachment means 36 further includes a third upside-down “L-shaped” bottom support rail 39 extending perpendicular from the bottom of the plate outer face 30 then angled parallel to the plate outer face 30 . In this embodiment, the parallel portions of the support rails 38 , 39 are configured to fit within a corresponding groove 40 within the door panel 14 . As visible in FIGS. 2 , 3 , and 4 A and 4 B, the plate outer face 30 is substantially rectangular in shape and the support rails 38 , 39 extend along both sides and the bottom of the plate outer face 30 . In this embodiment, the door panel 14 may be secured to the door plate 12 by sliding the door panel 14 downwards onto the side support rails 38 and coming to rest on the bottom support rail 39 , such that the support rails 38 , 39 mechanically interlock with the groove 40 .
In a preferred embodiment, the door plate 12 and door panel 14 each include complementary apertures 42 , 44 . A portion of the stem portion 24 of the door handle 16 serially passes through the door panel aperture 44 and into the door plate aperture 42 . The portion of the stem portion 24 extending through the door panel aperture 44 mechanically secures the door panel 14 to the door plate 12 .
The door panel 14 and handle panel 18 each include a decorative design, which may include an image, words, or a combination of the two, such as, for example, a sports team logo, a sports team name, an image of a famous individual, an image of an animal, an image of a vehicle, or other desirable design. Preferably the decorative designs on the door panel 14 and handle panel 18 are complementary and provide a consistent decorative theme, such as, for example, a sports team logo on the handle panel 18 and the team name on the door panel 14 , or an image of a skull and cross bones on the handle panel 18 and the words “abandon hope all ye who enter” on the door panel 14 .
In one embodiment, as shown in FIGS. 5A-5D , the door panel 14 is comprises a first door panel part 46 and a second door panel part 48 . The first door panel part 46 is a transparent material and the second door panel part 48 is an opaque material. The first door panel part 46 includes a first door panel inner surface 50 and an opposing first door panel outer surface 52 . In this embodiment, a decorative design is applied on the first door panel inner surface 50 of the first door panel part 46 . The first door panel inner surface 50 is then secured to the second door panel part 48 by an attachment means, such as, for example, a transparent adhesive. The door panel 14 is attached to the door plate 12 such that the first door panel outer surface 52 of the first door panel part 46 is arranged outwards from the door plate 12 . The first door panel part 46 is sized to cover at least a portion of the plate outer face 30 . In the preferred embodiment shown in FIGS. 1-3 and 5 A- 5 D, the first door panel part 46 is sized to cover substantially all of the plate outer face 30 .
In the embodiment shown in FIGS. 5A-5D , the first door panel part 46 and second door panel part 48 are designed to form a groove 40 when combined to form the door panel 14 . A notch is formed in the edges of the surface of the rectangular second door panel part 48 which will contact the first door panel part 46 . When the first door panel part 46 and second door panel part 48 are secured together, the notch and first door panel inner surface 50 cooperatively form the groove 40 .
The decorative design may be applied to the door panel 14 via screen printing, drawing, painting, carving, etching, or other suitable means. In a preferred embodiment, the decorative design is applied via screen printing to a first door panel inner surface 50 of a transparent first door panel part 44 made of acrylic. In this embodiment, the opaque second door panel part 48 is also made of acrylic. The opaque second door panel part 48 serves as the background of the decorative design on the first door panel part 46 . In another embodiment, the decorative design is applied via screen printing to an opaque acrylic second door panel part 48 , and a transparent acrylic first door panel part 46 includes no markings. By applying the design to one of the first door panel inner surface 50 and the second door panel part 48 , and irreversibly securing the two together, moisture, abrasions, and scratches cannot reach and damage the design. Instead, the design is viewed through the transparent body of the first door panel part 48 .
The handle panel 18 is constructed using similar techniques as the door panel 14 . In one embodiment, as shown in FIGS. 6A-6C , the handle panel 18 is constructed of a first handle panel part 54 and a second handle panel part 56 . The first handle panel part 54 is a transparent material and the second handle panel part 56 is an opaque material. The first handle panel part 54 includes a first handle panel inner surface 58 and an opposing first handle panel outer surface 60 . In this embodiment, a decorative design is applied to one of the first handle panel inner surface 58 and the second handle panel part 56 using techniques as described above for the door panel 14 . The first handle panel inner surface 58 is then secured to the second handle panel part 56 by an attachment means, such as, for example, a transparent adhesive. The handle panel 18 is attached to the handle outer face 22 such that the first handle panel outer surface 60 is arranged outwards from the door handle 16 . The handle panel 18 is sized to cover at least a portion of the handle outer face 22 . In a preferred embodiment, the handle panel 18 is sized to cover substantially all of the handle outer face 22 .
FIG. 7 depicts a second embodiment of a door fixture 110 within the scope of the present invention. This second embodiment is substantially identical to the first embodiment, except as described below.
In this second embodiment, the handle outer face 122 is recessed into the graspable portion 120 to a distance equal to the height of the handle panel 118 , such that outer surface 160 of the handle panel 118 is flush with the graspable portion 120 and provides the appearance that the handle panel 118 and graspable portion 120 are a single piece. In this embodiment, the plate attachment means 136 is a flange 138 extending outward from the perimeter of the plate outer face 130 to a height substantially equal to the height of the door panel 114 , such that the outer surface 152 of the door panel 114 is flush with the flange 138 and provides the appearance that the door panel 114 and the door plate 112 are a single piece. The door panel 114 is affixed to the plate outer face 130 and flange 138 via an adhesive or other suitable means.
While the present invention is discussed and shown primarily in context of an axially symmetric knob-type door handle 16 attached to a generally rectangular door plate 12 , the invention is not limited to these particular shapes. The door plate 12 may be generally circular, oval, or a non-standard shape. The door handle 16 may be a knob, lever, or other graspable shape. The present invention may also be used in residential, commercial, industrial, or other settings. In one embodiment, the decoration on the door fixture 10 may also serve a functional purpose in addition to an aesthetic purpose. For example, the decoration on the door fixture 10 used in a laboratory setting could include a radioactivity hazard design on the handle panel 16 and the words “Warning: Radiation Hazard” on the door panel 14 . For another example, the door fixture used on a restroom in a commercial facility could include the word “Women” on the handle panel 16 and a design showing the outline of a woman on the door panel 14 .
The foregoing detailed description is given primarily for clearness of understanding and no unnecessary limitations are to be understood therefrom for modifications can be made by those skilled in the art upon reading this disclosure and may be made without departing from the spirit of the invention and scope of the appended claims. | The present invention relates to a door fixture with decorative panels. More particularly, the present invention relates to a door fixture comprising a handle attached to a door plate, a handle panel attached to the handle and a door plate panel attached to the door plate, the door plate being affixed to a door. | 8 |
This is a continuation, of application Ser. No. 08/397,339, filed Mar. 2, 1995, now abandoned, which is a Continuation-In-Part of U.S. Ser. No. 08/205,059 filed Mar. 2, 1994, now abandoned.
TECHNICAL
This invention relates generally to anti-stick coatings for tacky polymer particles or particulate polymer blends and methods for applying the coatings. More specifically, this invention relates to an anti-stick coating and a method for coating particles of adhesives, polyolefins, and polyolefin blends.
BACKGROUND
As long as there have been tacky polymers or blends of polymers, transporting and handling these materials has been a problem. The problem is due to the agglomeration or sticking together of these polymers. These polymers are solid or semi-solid at room temperature. After polymerization, blending, or formulating, the polymers are solidified in some particulate form, such as pellets, spheres, granules or other shapes such as pillows. Those of ordinary skill in the art will appreciate that there are many geometries for such polymers. However, whatever geometry is chosen, agglomeration remains a problem.
There are several classes of polymers or polymer blends that are tacky or have a tendency to stick to one another or to their container. These may include, but are not limited to ethylene copolymers, propylene copolymers, or adhesives such as hot melt adhesives and pressure sensitive adhesives. With the growth of the volume of these materials produced in the world, the need to transport them in larger quantities has grown as well.
Generally, these polymers are rendered tacky by a number of factors. These factors include the comonomer amount, the comonomer type, the melt index or viscosity, the softness of the polymer, and the inherently tacky materials that can be added to polymers to improve their performance in intended end uses, such as adhesives. The low secant moduli and/or the relatively low softening points make the deformation of these materials under weight, pressure, and/or heat a particular problem. Such deformation allows the surface contact area of the particles, pellets, spheres, pillows or granules to increase. This deformation is known by several names such as creep or cold flow.
Further aggravating the polymer's tendency towards tackiness is the method of transport used to convey these products to the end user. Transporting modes can be 5 to 25 kilograms in a bag, as much as 300 or 1000 kilograms in boxes or bins, or even in bulk truck or rail containers where 15,000 to 90,000 kilograms are shipped at a time. In such shipments, the polymer's natural tendency to stick to itself or to the container is amplified by the weight of the polymer on itself, and, in the case of bags, the weight of other bags stacked one on the other for shipping and/or storage. Compounding this situation are warm or hot conditions such as seen in summer in much of the world, or year around conditions in tropical or semi-tropical climates. One reason for this aggravated tendency to agglomerate or stick together at elevated temperatures is that as the polymers get closer to or exceed their softening points they can deform to such an extent to stick together to form a large matrix or even a solid block.
However, in less severe conditions, the polymers may only stick together at their initial contact points without substantial deformation. Under such conditions the pellets or other polymer shapes may not fuse, but their intimate contact causes them to stick together, necessitating some form of physical breaking of the sticking to permit handling. Such physical breaking apart of agglomerated particles could be as simple as using a shovel or other instrument to weaken or break the sticking points such that the sticking points are eliminated to allow relatively free flow, or breaking enough of the sticking points to allow the material's weight to break the remaining sticking points. In either case this can cause use of additional labor, and lead to potential safety concerns. In some cases, freeing such fused polymer can be substantially impossible where cold flow has resulted in substantially a block of fused polymer or where the polymer is contained in a substantially inaccessible container.
Also contributing to the sticking, bridging, or fusing problem is the particle geometry and size. Smaller particles, in general, have greater surface area to volume ratios and, therefore, more contact than larger particles.
A number of ways to solve the agglomeration problem have been tried in the past with varying degrees of success. One method is to coat the materials with a microfine dust or powder of polyethylene homopolymer or copolymer. This method is generally not effective in cases where the powder has a higher melting point than the polymer coated, as the coating material can cause melting point variations, phase separation, poorer clarity (especially in adhesive formulations), loss of tenacity or bonding strength, or other problems in the fabrication or compounding of the coated polymers. This method is difficult to use commercially, as the powder or dust can cause explosion risks in a commercial environment. Additionally, there is usually only a weak bond between the coating and the base polymer, resulting in a partial removal of the coating during shipping and handling due to vibrations and particle movement. This removal will reduce or eliminate the coating's beneficial effect, and additionally pose another potential problem of loose dust that will complicate the handling of the polymer particles, for instance by plugging air filters on pneumatic conveying equipment.
U.S. Pat. No. 3,528,841 discloses a decrease in tackiness of polymers by coating with a parting agent that is a polyolefin powder. The powder is applied in the range of 250 ppm to 1000 ppm. The parting agent is dispersed in water by a block copolymer of ethylene oxide and propylene oxide.
U.S. Pat. No. 3,779,785 discloses a low melting point wax used as a parting agent for ethylene-vinyl acetate copolymers. The wax is employed in the form of a finely divided aqueous emulsion. The wax level is 1% to 5% by weight.
Another method of solving the sticking polymer problem is to blend into the polymer fatty amides that are known to be incompatible with the polymer. The incompatibility of these fatty amides will cause them to “bloom” or exude to the surface of the polymer particle. This method has been proposed to reduce sticking of pellets to one another. There are at least two problems associated with this proposed solution. The first is that when such additives are put into a polymer pellet, the blooming is a slow time related function. It is quite likely that these fatty amides will not bloom to the pellet surface in time to prevent agglomeration and/or fusing. Second, in many polymer applications, the polymer may not be processed through a melt extruder before loading in a container for transport, thereby eliminating the ability to add these additives without further cost and delay.
U.S. Pat. No. 4,510,281 discloses tack-free polymer pellets, defined by a stick point of 40° C. at most (for ethylene vinyl acetate copolymers) and other polymers having a stick point of less than 60° C. The polymers are ethylene vinyl acetates, terpolymers of ethylene with vinyl acetate and carbon monoxide, copolymers of methacrylic acid, copolymers of ethylene methylmethacrylate and terpolymers of ethylene, n-butyl acrylate and carbon monoxide. An ethylene bisoleamide additive is blended with the polymers and then melt extruded into pellets.
Another method to reduce the agglomeration problem is to change the shape or geometry of the solid polymer, polymer blend, or adhesive to, for instance, a “pillow” shape. Such a technique is viable usually only when the polymer or blend is adequately hard in the frozen or solid state at room or slightly elevated temperatures, to prevent sticking. Alternatively, reducing the contact area per unit volume, by making larger particles has practical limits for materials such as polyolefins which are usually pneumatically conveyed.
There exists a need for an easily applied, effective, non-deleterious coating and coating method that will permit storage, shipping and handling of many types of soft, tacky polymer particles.
SUMMARY
It has been discovered that a combination of emulsifiable waxes, surfactants, and bases, in a water emulsion, combined with an anti-stick agent or agents in the emulsion, gives a coating to polymer particles that is both relatively easy to apply and effective in preventing sticking or agglomeration.
The polymer particles are selected from the group consisting of:
a) copolymers of ethylene and an ethylinically unsaturated ester or a carboxylic acid, where the comonomer is present in the range of from about 5 to about 25 mole percent based on the total moles of the copolymer, and the comonomer is chosen from the group consisting of vinyl acetate, ethyl acrylate, methyl acrylate, n-butyl acrylate, isobutyl acrylate, methyl methacrylate, acrylic acid, methacrylic acid, or combinations of one or more of these comonomers as well as their ionomeric partial salts;
b) ethylene alpha-olefin copolymers and terpolymers (These will generally have comonomer contents in the range of from about 0.2 to about 20 mole percent based on the total moles of the copolymer or terpolymers. These materials tend to become soft, tacky, or sticky below about 0.91 g/cc density. Such copolymers and terpolymers are both semi-crystalline to amorphous) the alpha-olefins are selected from 1-butene, 1-hexene, 1-octene, or combinations of these alpha-olefins;
c) hot melt adhesives which are mixtures of polymer and adjuvants, usually tackifying resin, wax or low glass transition temperature (T g ) materials such as oils and low molecular weight polymers;
d) pressure sensitive adhesives which are similar to hot melt adhesives, with the addition of oils and other adjuvants;
e) polypropylene copolymers and terpolymers which generally include propylene ethylene copolymers and propylene alpha-olefin copolymers where the alpha-olefin is selected from the group consisting of 1-butene, 1-hexene, 1-octene or a combination of these monomers (The alpha-olefin(s) is present in the range of from about 0.2 to about 20 mole percent based on the total moles of the copolymer or terpolymer);
f) polypropylene blends including blends of an elastomer or a low molecular weight hydrocarbon; and
g) ethylene propylene (EP) and ethylene propylene diene monomer (EPDM) polymer elastomers.
More particularly, the invention relates to anti-stick agents that may be incorporated into the aqueous emulsions and methods for applying the resulting particle coating. The emulsion will be comprised of a surfactant present in the range of from about 2 to about 10 percent by weight, a base present in the range of from about 0.05 to 1.0 weight percent, an emulsifiable wax in the range of from about 3 to about 20 weight percent, and water in the range of from about 40 to about 60 weight percent and anti-stick additive in the range of from about 10 to about 60 weight percent of at least one anti-stick additive where the anti-stick additive is capable of preventing particles, pellets, or other shapes from sticking together. The anti-stick additives are selected from the group consisting of talc, silica, primary amides, secondary amides, ethylenebisamides, a second wax, or combinations of two or more of these anti-stick additives. The particle size of the emulsifiable wax will generally be in the range of from 0.01 μm to 0.2 μm, while the particle size of the anti-stick additives will generally be in the range of from 1 to 150 μm.
Under conditions of heat and pressure typically present during the storage and handling of these polymer particles or particles of polymer blends, these coatings will permit granules, pellets, or other shapes of polymer particles to be free flowing.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Introduction
In certain embodiments of the present invention concerns certain classes of polymers, and coatings for these polymers, that are effective in reducing the polymer's tendency to stick to itself or agglomerate. Ethylene copolymers, propylene copolymers, and adhesives that in their uncoated form exhibit a tendency to stick to one another or to their container, are coated with a material that reduces or substantially eliminates the sticking or agglomerating. A detailed description follows of certain preferred coatings for use in coating polymers and preferred methods for applying these coatings.
Those skilled in the art will appreciate that numerous modifications to these preferred embodiments can be made without departing from the scope of the invention. For example, though the properties of copolymers of ethylene and ethylinically unsaturated esters are used to exemplify the attributes of the coated polymers, many other types of tacky and/or soft polymers may be used. Further, although emulsions containing certain anti-sticking agents are used in the examples that follow, many other materials or compounds may be used. To the extent that our description is specific, this is solely for the purpose of illustrating preferred embodiments of our invention and should not be taken as limiting our invention to these specific embodiments.
The Coatings
We have discovered that certain combinations of emulsifiable waxes, surfactants, bases, and anti-stick materials can be used to easily and effectively prevent agglomeration, bridging or sticking of polymer pellets or other shapes, under storage and handling conditions involving pressure, weight, or heat or a combination thereof. These materials, when combined in a liquid solution or emulsion, permit easy and effective application. Generally the materials effective in preventing sticking are chosen from inorganic materials such as talc or silica or alternatively organic materials such as primary amides, secondary amides, ethylenebisamides, waxes or combinations of these materials.
Components of the Coating Formulation
The coating formulation can be based on aqueous emulsion materials such as those available from Eastman Chemical Co. under the trade name Aquastab®. These materials, and methods of making them, are described in U.S. Pat. Nos. 4,898,616 and 4,880,440 by Hyche, et al. These U.S. Patents are incorporated by reference in the present application for purposes of U.S. Patent practice.
Preferably, the aqueous emulsion materials will have in the range of from about 2 to about 10 weight percent of a surfactant, a base in the range of from about 0.05 to 1.0 weight percent, an emulsifiable wax in the range of from about 1 to about 20 weight percent, in the range of from about 20 to about 60 weight percent of at least one additive capable of preventing sticking or agglomeration. The balance of the formulation would be a liquid, preferably an aqueous-based mixture of a water-miscible material and water, more preferably deionized water.
The base may be selected from sodium tetraborate, sodium carbonate, potassium hydroxide, sodium bicarbonate, calcium carbonate or magnesium carbonate. The base imparts to the emulsion a pH of in the range of from about 7 to about 10.5.
The emulsifiable wax is chosen from any wax which can be readily emulsified, for instance, emulsifiable polyolefin waxes such as oxidized polyolefin waxes. The emulsifiable wax is characterized by a melting point of up to about 135° C. Those of ordinary skill in the art will understand that many factors affect the emulsification process, and the ability of an emulsion to retain its stability. Generally the emulsifiable wax will have a particle size small enough that the particle size will not significantly contribute to instability of an emulsion. However, the range of particle size for the emulsifiable wax in the emulsion, will be below 0.2 μm in the range of from 0.01 to 0.2 μm, more preferably from 0.05 to 0.2 μm.
The surfactant is chosen from aliphatic alcohols or ethoxylated aliphatic alcohols.
The anti-sticking additive is selected from talc (such as ABT-2500 from Pfizer Inc.), diatomaceous earth (such as Celite from Manville Corp.), amorphous silica (such as Davison 955 from W. R. Grace), primary amides such as for instance stearamide, arachidamide, behenamide, oleamide and erucamide, secondary amides, such as for example stearyl erucamide, erucyl erucamide, oleyl palmitamide, oleyl oleamide, stearyl stearamide and erucyl stearamide, ethylenebisamides, such as for example ethylene biserucamide, ethylene bisstearamide, and ethylene bisoleamide, waxes such as paraffinic, isoparaffinic or Fischer-Tropsch wax, or combinations of these materials.
The anti-stick additive is placed in the emulsion at a level that will be both economical and effective to prevent sticking or agglomeration of the coated particles, pellets or other shapes. To attain the goal of economy, the amount of anti-stick additive in the emulsion should be maximized consistent with maintaining the emulsions ability to be pumped and sprayed. A reason for limiting the amount of anti-stick additive deposited on the polymer particle, is the possibility of deleterious effects on the end use product properties. It will be understood by those of ordinary skill in the art that substantially lower amounts of the anti-stick additive may be put in the emulsion. The lower limit of anti-stick additive in the emulsion is defined by the amount that will substantially reduce particle sticking under storage and handling conditions.
The anti-stick additive may be added to the emulsion in the range of from about 10 to 60 weight percent based on the total weight of the blended emulsion. Preferably the anti-stick additive will be present in the range of from about 20 to about 60 weight percent. More preferred is a range of from about 30 to about 55 weight percent. Most preferred in the range of from about 40 to about 50 weight percent.
The anti-stick additive will have a particle size mean generally exceeding 1 μm, preferably exceeding 3 μm. More preferably the anti-stick additive will have a mean particle size in the range of from 3 to 150 μm, even more preferably in the range of from 2-100 μm, most preferably in the range of from 15 to 75 μm. It will be understood by those of ordinary skill in the art that by, mean particle size, Applicants intend that the mean will be descriptive of a distribution, and not generally include particles of only one size rather a distribution of sizes. Also note that the particle size distributions are generally non-Gaussian, accordingly the distributions can include relatively small percentages of particles on either end of the distribution that will be either extremely small or extremely large compared to the mean.
The emulsion may be placed on the polymer particles in ways that will be apparent to those of ordinary skill in the art. These methods include spraying or dipping. Spraying is preferred. Subsequent to application, drying may be carried out in any manner, but is most effectively carried out by pneumatically conveying the particles. Subsequent to drying, the polymer particles are left with a substantially continuous coating that will have definable contents of some of the emulsion ingredients. For instance, the emulsifiable waxes and anti-stick agents will be substantially preferentially left on the polymer surface, while the other ingredients, for instance, the base and the surfactant will tend to preferentially be substantially removed with the water during the drying process.
The minimum amount of anti-stick additive on a treated polyolefin or adhesive will be understood by those of ordinary skill in the art to be that amount that will substantially eliminate the sticking of the polyolefin or adhesive under its conditions of storage and handling. The upper limit will be defined by an amount that begins to interfere in the end use properties of the polymer or inhibit the handling and application of the emulsion.
The particle size of the anti-stick additive is also understood to be a size or size distribution that at certain concentrations performs the function of maintaining polymer particle flowability. Other factors affecting efficiency of the anti-stick coating are hardness and concentration in the emulsion and/or on the polymer particles to be treated.
This anti-stick level will generally range from about 100 parts per million (ppm) (based on the weight of the polymer) to about 8,000 ppm. Preferably the levels will be in the range of from about 500 ppm to about 7,000 ppm. More preferably the levels will be in the range of from about 1,000 ppm to about 6,000 ppm. Most preferred is a range of from about 1,000 ppm to about 4,000 ppm. Hardness and particle size of the anti-stick addiditve play a part in the efficacy of the anti-stick additive, and these factors combined with the level of inclusion (concentration) are determinative of a specific anti-stick additives effectiveness.
The amount of emulsifiable wax on the polymer surface after drying will be in the range of from about 50 to 2000 ppm, preferably 100 to 1500 ppm, more preferably from 200 to 1500 ppm.
The invention will be further illustrated by the following examples although it will be understood that these examples are included merely for purposes of illustration and are not intended to limit the scope of the invention. Concentrations listed in the Examples are in parts per million by weight (ppm) and temperatures are in ° C.
Three types of tests were run. The first, Protocol A, is performed as follows. The polymer particles are visually inspected on a flat surface. The amount of sticking together, movement relative to one another, or sticking to the surface is noted after moving particles with an instrument. If the particles or pellets exhibit sticking to one another and/or dragging on the flat surface, the particles are deemed not to be free flowing and compaction testing is not attempted, because experience has shown that if the pellets agglomerate on a flat surface, the agglomeration in a compaction test would be unacceptable. If the particles flow freely on a flat surface and do not visibly stick to each other, the compaction test is used.
The second type of test run is a compaction test, Protocol B. Two to ten grams (the weight of the sample will depend upon the product's density and bulk density) of a sample is placed in a compaction cell. The compaction cell volume is approximately 12.5 cm 3 , the diameter of the cell is about 25 mm, and the height is approximately 25 mm. A load is placed on the polymer of either 280 grams or 1 kilogram to simulate either a loaded box (Condition 1) or loaded bulk rail car (Condition 2), respectively. The cell with the weight is placed in an oven for 24 or 48 hours at one or more of three temperatures, 38° C., 49° C. and 60° C. These conditions are intended to simulate bulk handling of these polymers.
The third type of test run is a flowability test, Protocol C. This test is specifically designed to simulate both the internal geometry of a bulk rail car as well as a storage silo. Both geometries are replicated in a device that has a circular cross section and has an angled bottom. (30 cm. total length and 9 cm. internal diameter. The bottom of the cylinder narrows to 3 cm. in diameter at an angle 30° to the vertical). Approximately 500 g. of particles or pellets are placed in the container with the bottom covered. The container is placed in an oven for 3 days at 43° C. The silo is then removed from the oven, the bottom stop is removed, and the time it takes for the container to empty is recorded. If the pellets do not empty in 5 minutes (300 seconds), they are prodded from the bottom of the silo and the timing continued. If another 5 minutes elapses without the container emptying, the test is discontinued.
EXAMPLE 1
Run sets 1-11 are run as described below and the results are seen in Table 1. A 4 dg/min. melt index ethylene methyl acrylate copolymer (EMA-1) containing 32% by weight methyl acrylate is prepared. Nine sample sets are prepared using an Aquastab® emulsion. The emulsion is used without anti-stick additives (run sets 1-3) to determine the efficacy of the delivery emulsion itself as an anti-stick coating consisting of water, base, emulsifiable wax and surfactant. In run sets 1-3, the emulsion formulations are varied by using different levels of two different emulsifiable waxes. Run sets 1 and 3 use Epolene® E-14 (Eastman Chemical Co.), run set 2 used Epolene® E-20 (both E-14 and E-20 are believed to be low molecular weight polyolefin waxes). In run sets 1 and 2 the concentration of the emulsifiable wax on the polymer after drying ranges from 500 ppm to 10,000 ppm. In run 3 the concentration of wax ranges from 3,000 to 6,000 ppm. Neither of these waxes at any of the concentrations, provides a pellet surface that is free flowing on a flat surface, and the coated pellets of run sets 1 to 3 are not tested further.
Run sets 4 and 5 utilize conventional polyethylene anti-oxidants carried by the emulsion. In run 4, Irganox 1076® (Ciba Geigy) is used at a 3000 ppm level and in run 5, BHEB (2,6 di-tert butyl4-ethyl phenol) from 400 to 2000 ppm is added. In both runs 4 and 5, the pellets again remain tacky after coating and drying, so further compaction tests are not conducted.
Run sets 6 and 7 utilize talc (ABT 2500 from Pfizer Corp.) at a level of 2000 ppm and run set 8 an ethylene bisoleamide (EBO) at 3000 ppm. Run 9 is a combination of talc (2000 ppm) and EBO (3000 ppm). In runs 6-9 the pellets are observed to not stick together on a flat surface and are tested in compaction tests according to protocol B. The results shown in Table 1 ambient condition show that for run sets 6 and 7 pellets stick together, but break apart easily. At 60° C., during an extended test run of 72 hrs., the pellets are fused and not easily dislodged. The level of agglomeration of these polymer particles at 60° C. is judged to be unacceptable.
Pellets for runs 8 and 9 exhibit acceptable flowability after 24 hours at 38° C., but after 24 hours at 60° C. the flowability is judged unacceptable.
Runs 10 and 11 are made on coated pellets, where the coating technique used to deliver the anti-stick agent to the pellets was to “dust” the anti-stick agent onto the dry but sticky pellets. In both runs 10 and 11, (using talc and diatomaceous earth at 2000 ppm respectively). The pellets exhibit flowability substantially equal to that of runs 8 and 9. However, this application technique is used only for control purposes, as such a technique is generally unsuitable for large commercial installations.
TABLE 1
Protocol A
Protocol B
Concentration
Drying
Pellet Surface/
Condition 1
Condition 2
Run
Additive
(ppm)
Condition
Performance
Ambient
38° C.
60° C.
Ambient
38° C.
60° C.
1
Epolene E14
500-10000
50° C.
Very Tacky
2
Epolene E20
500-10000
50° C.
Very Tacky
3
Epolene E14
3000-6000
Ambient
Very Tacky
4
Irganox 1076
3000
50° C.
Pellets agglomerated
5
BHEB
400-2000
Ambient
Tacky
6
Talc
2000
Ambient
Free flowing
48 hr 4
72 hr 3
48 hr 4
7
Talc
2000
38° C.
Free flowing
8
EBO
3000
38° C.
Free flowing
24 hr 4
24 hr 2
9
Talc/EBO
2000/3000
38° C.
Free flowing
24 hr 4
24 hr 2
10
Talc
2000 1
—
Free flowing
24 hr 4
24 hr 2
24 hr 4
24 hr 2
11
Diatomaceous
2000 1
—
Free flowing
24 hr 4
24 hr 2
24 hr 4
24 hr 2
Earth
Notes:
1 Additive added by dusting the dry pellet surface.
2 Pellets fused during test, but not into a solid block.
3 Pellets fused into solid block during test.
4 Pellets “set-up” in cell configuration, but broke apart easily when touched.
EXAMPLE 2
The EMA-1 copolymer described in Example 1 and EVA-1, a 420 dg./min. melt index ethylene vinyl acetate copolymer containing 29% vinyl acetate were coated using the Aquastab emulsion delivery method. The coated pellets are placed in a compaction cell under 280 g. weight to approximate storage in a 454 kg box (Condition 1) and under 1 kg. weight to approximate storage in a 65,000 kg bulk rail car (Condition 2). Pellets remain under pressure for the indicated time and temperature. All coated pellets are free flowing with no applied pressure.
Runs 12-15 (Table 2) were used to determine differences between both different emulsifiable waxes and levels of oleylpalmitamide (OPA). Low molecular weight wax (lmw wax) and a montan ester (me) wax were tested as emulsifiable waxes, both at 2000 and 3000 ppm OPA levels. Table 2 represents averages of tests run under Condition 1 and Condition 2.
TABLE 2
OPA
Concentration
lmw wax
me wax
Run
Copolymer
(ppm)
38° C.
49° C.
60° C.
38° C.
49° C.
60° C.
12
EMA-1
2000
3
1
1
3
1
1
13
EMA-1
3000
3.5
1
1
3.5
1
1
14
EVA-1
2000
4.5
2
1
4.5
2
1.5
15
EVA-1
3000
4.5
2
1
4.5
2
1.5
1. Pellets fuse and do not break apart.
2. Pellets form a solid mass, but break apart with much pressure.
3. Pellets form a solid mass, but break apart with moderate pressure.
4. Pellets form a mass, but break apart into individual pellets with slight pressure.
5. Pellets remain separate.
Table 2 shows the results of the compaction testing using protocol B. The results demonstrate that for both EMA-1 and EVA-1, at a compaction test temperature of 38° C. (to simulate slightly elevated temperature conditions typical for storage and handling), the pellets are still flowable at both levels of OPA (2000 & 3000 ppm) with both emulsifiable waxes. However at higher temperatures, the pellets become unacceptably fused. A value of 2.5 or less is unacceptable.
For runs 16 and 17 (Table 3) EMA-1 and EVA-1 were tested according to protocol C, without any Aquastab emulsion or anti-stick additive. Results with the evacuation time above 300 seconds indicate an unacceptable fusing of the polymer, preventing flow.
TABLE 3
Emptying Time
(sec.)
Parting
Concentration
lmw
Run
Copolymer
Agent
(ppm)
wax
me wax
16
EMA-1
NONE
0
334
334
17
EVA-1
NONE
0
600+
600+
EXAMPLE 3
For runs 18-26 (Table 4) an EVA copolymer (480 dg/min. melt index ethylene vinyl acetate copolymer containing 28% vinyl acetate (EVA-2)) was used. The polymer had 1000 ppm of stearamide blended in the pellets. The pellets are further treated with one of two Fischer-Tropsch waxes (as anti-stick additives). The Fischer-Tropsch waxes have average diameters of 5 μm (FT-1) and 10 μm (FT-2). Two methods were used to deliver the anti-stick coating to the pellets. The Fischer-Tropsch wax is available from Moore & Munger, Shelton, Conn. under the tradename Paraflint® Spray 40 (mean particle size of about 13 μm (FT-2)) and Spray 30 (mean particle size of about 5 μm (FT-1)). The dusting technique of Example 1 (runs 10 and 11) and the Aquastab emulsion delivery method (emulsifiable wax, a base, a surfactant, water and the anti-stick additive). As shown in Table 4, the dusting technique provides a flowable product, however its general commercial applicability as discussed, is less favorable than an emulsion delivery technique.
When delivery is achieved using the Aquastab emulsion as the delivery method, the tack polymer particles begin to be acceptably flowable at about 1500 ppm of the FT waxes. Also of note is the difference between runs 21 and 22 where the 2 particle sizes appear (sprayed emulsion application) to have substantially the same emptying time, but at the next highest level of concentration, runs 23 and 24, the larger (≈10 μm mean particle size) FT wax performs clearly better. Further, at Further, at the 2000 ppm level (runs 25 and 26) the layer particle size wax (run 26) still shows an order of magnitude, better emptying time.
TABLE 4
Anti-Stick
Anti-Stick
Agent
Agent
Emptying Time (sec.)
(Mean Particle
Concentration
Sprayed
Run
Resin
Size μm)
(ppm)
Dusting
Emulsion
18
EVA-2
None
0
320
320
19
EVA-2
FT-1 (5)
500
12
313
20
EVA-2
FT-2 (13)
500
24
310
21
EVA-2
FT-1 (5)
1000
7
312
22
EVA-2
FT-2 (13)
1000
4
310
23
EVA-2
FT-1 (5)
1500
6
308
24
EVA-2
FT-2 (13)
1500
7
59
25
EVA-2
FT-1 (5)
2000
5
110
26
EVA-2
FT-2 (13)
2000
4
24
EXAMPLE 4
A set of runs (runs 27-29 Table 5) was made using a second EMA resin (EMA-2), a 5 dg./min. melt index ethylene methyl acrylate copolymer with 27% methyl acrylate. EMA-2 is coated with FT-2 as an anti-stick agent using the Aquastab delivery system. EMA-2 is slightly harder than EMA-1 and EVA-1, and should show a lower tendency to agglomerate in an uncoated state. Referring to Table 3 EMA-1 and EVA-1 empty in 334 seconds, and 600+seconds, respectively, versus EMA-2 (Table 5) at 319 seconds. Even with this slightly harder resin, at 0% additive, the resin had an unacceptable flow (319 seconds), but after addition of 1000 ppm or above, of the anti-stick agent, the flow properties proved to an acceptable level.
TABLE 5
EMA-2
FT-2 Concentration
Emptying Time
Run
(ppm)
(sec.)
27
0
319
28
1000
61
29
2000
24
EXAMPLE 5
A set of runs using EVA-3, a 420 dg/minute melt index, 28% (weight) viny/acetate content copolymer, available from Exxon Chemical Company under the grade name XW-41. The EVA-3 material is coated with Aquastab® emulsions containing varying concentrations (500 ppm increments starting at 1500 ppm up to 3000 ppm) of varying mean particle size distribution ranging from a nominal 5 μm to a nominal 50 μm. The larger particle size distribution tend to generally show good emptying time (less than 300 sec) at lower concentrations.
Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. For example, other coating techniques and other anti-stick additives are contemplated. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein. | Emulsion delivery systems for applying anti-stick additives to polymer particles, provide free-flowing particles of polymers or polymer blends, that without the anti-stick additives tend to agglomerate. The agglomeration presents storage and handling difficulties. The anti-stick additives are selected from the group consisting of primary amides, secondary amides, ethylene bisamides, waxes, talc and silica. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention is generally related to bowling ball dynamics, and more particularly to a system and method for variably altering the dynamics of a bowling ball on a bowling lane.
[0003] 2. Discussion of the Background
[0004] In the sport of bowling, aside from the technique of the bowler, numerous factors determine how a ball rolls and slides down a bowling lane. The ability of a bowler to compensate for these factors is important. These factors include without limitation: the lane conditions; the placement of the finger and thumb holes; the weight of the bowling ball; and the amount of positive and negative top, bottom and side weights on the bowling ball. Bowling lane conditions vary depending upon the lane surface, the amount of oil applied to the lane and other factors.
[0005] Bowling ball regulations in the United States typically regulate that weight of a bowling ball not exceed 16 pounds and have an outside diameter of approximately 8.550 to 8.595 inches. The placement of the finger and thumb holes, and the amount of positive and negative top, bottom and side weights impacts the rolling dynamics of the bowling ball on a bowling lane.
[0006] In the prior art, the amount of positive and negative top, bottom and side weights were permanently adjusted with respect to the bowling ball and could not be modified without additional permanent modifications to the bowling ball. As such, bowling users would typically utilize multiple bowling balls having differing positive and negative top, bottom and side weights in order to utilize the optimum bowling ball dynamics for a particular bowling lane. The use of multiple bowling balls is both costly and inefficient.
[0007] Thus, there currently exist deficiencies associated with bowling ball dynamics, and, in particular, with altering the dynamics of a bowling ball on a bowling lane.
SUMMARY OF THE INVENTION
[0008] Accordingly, one aspect of the present invention is to provide a system for variably altering the dynamics of a bowling ball. The system includes (i) a spherical bowling ball, (ii) one or more weight holes arranged along the outer perimeter of the bowling ball and extending radially inward therein forming an open cavity therebetween, and (iii) one or more removable weight inserts configured to be inserted into and engage the respective weight holes during an operational use thereof such that the one or more removable weight inserts substantially cover and close the one or more weight holes. Each of the removable weight inserts have a positive or negative weight effect and include indicia designating the weight of the respective removable weight insert.
[0009] Another aspect of the present invention is to provide a method for variably altering the dynamics of a bowling ball. The method includes (i) drilling one or more weight holes arranged on the outer perimeter of the bowling ball and extending radially inward therein forming an open cavity therebetween, (ii) selecting one or more removable weight inserts, and (iii) seating the selected one or more removable weight inserts into a corresponding one or more weight holes during an operational use thereof such that the one or more removable weight inserts substantially cover and close the one or more weight holes. Each of the removable weight inserts have a positive or negative weight effect and include indicia designating the weight of the respective removable weight insert.
[0010] Yet another aspect of the present invention is to provide a system for variably altering the dynamics of a bowling ball. The system includes (i) a spherical bowling ball, (ii) a first and second set of finger and thumb holes arranged at different positions along the outer perimeter of the bowling ball and extending radially inward therein forming an open cavity therebetween, (iii) one or more weight holes proximate to the first set of finger and thumb holes and arranged along the outer perimeter of the bowling ball and extending radially inward therein forming an open cavity therebetween, (iv) one or more weight holes proximate to the second set of finger and thumb holes and arranged along the outer perimeter of the bowling ball and extending radially inward therein forming an open cavity therebetween, and (v) one or more removable weight inserts configured to be inserted into and engage the respective weight holes and second set of finger and thumb holes during an operational use thereof such that the one or more removable weight inserts substantially cover and close the one or more weight holes and second set of finger and thumb holes. Each of the removable weight inserts have a positive or negative weight effect and including indicia designating the weight of the respective removable weight insert.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] A more complete appreciation of the present invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings, wherein:
[0012] FIG. 1 shows a top plan view of an improved bowling ball in accordance with an embodiment of the present invention;
[0013] FIG. 2 shows a sectional view of an improved bowling ball in accordance with an embodiment of the present invention;
[0014] FIG. 3A shows a sectional view of an improved bowling ball with one or more weight inserts in a non-operational position in accordance with an embodiment of the present invention;
[0015] FIG. 3B shows a sectional view of an improved bowling ball with one or more weight inserts in an operational position in accordance with an embodiment of the present invention;
[0016] FIG. 4A shows a sectional view of an improved bowling ball with an alternate weight insert in accordance with an embodiment of the present invention;
[0017] FIG. 4B shows a sectional view of an improved bowling ball with an another alternate weight insert in accordance with an embodiment of the present invention;
[0018] FIGS. 5A-5D show top plan views of weight inserts showing differing head types in accordance with an embodiment of the present invention; and
[0019] FIG. 6 shows a top plan view of an improved bowling ball in accordance with an alternate embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, preferred embodiments of the present invention are described.
[0021] A bowling ball is typically comprised of urethane, plastic, reactive resin or a combination of these materials. The bowling ball consists of a hard outer shell with a weight block molded into the core of the bowling ball. Amongst other factors, the mass and shape of the weight block affects the spin of the bowling ball and how it curves as it rolls down the bowling lane. Bowling regulations typically allow for a maximum weight of 16 pounds and a maximum diameter of 8.6 inches. Bowling balls generally include two finger holes and one thumb hole for gripping the bowling ball.
[0022] As shown in FIG. 1 , a bowling ball positive axis point (PAP) is the initial axis of rotation of the bowling ball as soon as it begins traveling down the lane, where W 0 is the initial rotation speed of the bowling ball. The PAP and W 0 both depend on, amongst other factors, the bowler's release technique. Every bowler has their own release technique so the PAP is different for each bowler. For each bowler, the PAP is generally in a fixed location relative to the finger and thumb holes. As shown in FIG. 2 , an imaginary line originates from the geometric center C of the bowling ball and passes through the center of mass G of the bowling ball. The intersection of this line with the surface of the bowling ball is called the center of gravity CG.
[0023] The optimal trajectory of a bowling ball is a curved path where it strikes the pins on the bowling lane at an angle. Striking the pins at an angle improves the chances that there will be a strike in which all of the pins are knocked down. If the ball follows a curved path along the bowling lane, it will be able to strike the pins at a greater angle than a bowling ball that travels in a straight line. Therefore, controlling the curved path of the bowling ball along the bowling lane is essential to making the best possible shot.
[0024] The length of a typical ten-pin bowling lane in the United States is 60 feet. The bowling lane is typically oiled to protect it from wear, especially during the initial sliding stage of the bowling ball before it begins pure rolling. The angular velocity vector typically changes direction as the ball travels down the lane due to friction between the ball and the lane.
[0025] Typically, during the first part of the motion, the bowling ball slides along the lane since its rotational speed does not match the linear velocity of the ball. The lane friction and the bowler's release technique eventually stop the ball from sliding and pure rolling begins. The ball then continues rolling down the bowling lane until it hits the pins. The ball hits the pins at an angle (θ). Ideally, the front-most pins are hit first by the bowling ball at an oblique angle, since this will most likely result in a strike. The closer this angle is to the optimum angle, the greater the chance that all the pins will be knocked down.
[0026] The amount of deflection (δ) that the bowling ball travels down the bowling lane is called the “hook” in the trajectory of the bowling ball. It is the sideways deflection of the ball from its original trajectory.
[0027] The location of the PAP relative to the pins on the bowling ball determines how much the bowling ball precesses as it travels down the lane. Consequently, the level of precession is directly proportional to the level of friction between the lane and the bowling ball. The level of friction, in turn, has a large influence on δ and θ. More precession leads to more friction and results in more hook, and less precession leads to less friction and results in less hook. A principal influence on ball motion is friction between the bowling ball and the bowling lane, whether it's due to friction influenced by ball precession or lane conditions (e.g., oiled vs. non-oiled).
[0028] The amount of positive and negative top, bottom and side weights on the bowling ball is also important in influencing the amount of hook δ, and impact angle θ. Therefore, these weights should be optimized for the bowling lane conditions and the bowler's technique, in order to get the best possible shot. Positive and negative side weights effect when and how much the ball will hook. A ball with positive side weight (i.e., finger weight) will hook later and hook more. A ball with negative side weight (i.e., thumb weight) will hook sooner and hook less. United States bowling regulations place a limit of up to one ounce of side weight, either positive or negative. Top weight effects how far the ball will go down the lane before it snaps on the backend of the bowling lane. Likewise, bottom weight makes the ball roll earlier and arc more. United States bowling regulations place a limit of up to three ounces of top weight and/or bottom weight, either positive or negative.
[0029] Referring to FIG. 1 , a top plan view of an improved bowling ball 10 in accordance with an embodiment of the present invention is shown. The bowling ball 10 includes a spherical outer shell 12 , a weighted inner core (not shown), and finger and thumb holes ( 14 , 16 and 18 ) drilled into the outer shell of the bowling ball 10 . A bowler engages the finger and thumb holes ( 14 , 16 and 18 ) and by means of a swinging motion, propels the bowling ball 10 toward a bowling pin arrangement at the end of a bowling lane. The bowling ball 10 assumes any one of a number of trajectories as it slides and rolls along the lane until it strikes the pins.
[0030] The bowling ball 10 also includes one or more weight inserts 22 and corresponding weight holes 20 arranged along the outer perimeter of the bowling ball 12 and extending radially inward therein forming an open cavity therebetween. Referring to FIGS. 3A and 3B , a sectional view of an improved bowling ball 10 with one or more weight inserts 22 and corresponding weight holes 20 in accordance with an embodiment of the present invention is shown. In particular, FIG. 3B shows the one or more weight inserts 22 in their operational inserted position in corresponding weight holes 20 . In their respective operational positions, the one or more weight inserts 22 substantially cover and close corresponding weight holes 20 such that in their operational positions, the perimeter surface of the bowling ball has substantially the same condition as if the weight holes 20 were not present. According to one embodiment, the one or more weight inserts 22 are configured and sized such that they are held in place by means of frictional engagement. According to an alternate embodiment, the one or more weight inserts 22 are configured and sized such that they are held in place by means of a locking mechanism such as the arrangement shown in FIG. 4B . According to this arrangement, the locking mechanism consists of a locking portion 28 which extends from a bottom end of the one or more weight inserts 22 and a corresponding locking portion 26 which extends from a bottom end of the one or more weight holes 20 . The locking portion 28 is inserted into an appropriately sized opening of the corresponding locking portion 26 and twisted into a locked operational position.
[0031] According to one embodiment, the one or more weight inserts 22 include weight increments of 0.5 ounces (i.e., −1.0, −0.5, 0.0, 0.5 and 1.0 ounces for side weight inserts, and −3.0, −2.5, −2.0, −1.5. −1.0, −0.5, 0,0, 0.5, 1,0, 1.5, 2,0, 2.5 and 3.0 ounces for top and bottom weight inserts). More commonly, and without limiting, a bowler would start at 0.0 ounces and add increments of 0.5 ounces up to the legal weight for the side or top weight. Obviously, other weight increments are possible within the scope of the present invention. The head of the one or more weight inserts 22 may include indicia for indicating the weight of the respective weight insert 22 . The indicia may include, without limitation, a unique color, a label, an image, or the like. It is envisioned that United States bowling regulations would be modified to specific regulated indicia so that it may be standardized for case of use and inspection. This would be particularly helpful during a sanctioned bowling tournament. The head of the one or more weight inserts 22 may also include a means for inserting and removing the respective weight inserts, such as, without limitation, one or more spanner holes for use with a corresponding spanner wrench. For example, the one or more weight inserts 22 may include one or more spanner holes ( 24 a and 24 b ) as shown in FIG. 5C . According to one embodiment, the one or more weight inserts 22 consists of the same material used in the bowling ball.
[0032] Referring to FIG. 4A , a sectional view of an improved bowling ball with an alternate one or more weight inserts 22 and corresponding weight holes 20 in accordance with an embodiment of the present invention is shown. According to this arrangement, one or more weight holes 20 are internally threaded and configured to receive the one or more weight inserts 22 which are also threaded and configured to substantially cover and close corresponding weight holes 20 when the weight inserts 22 are screwed into their respective operational positions. As shown in FIGS. 5A-5D , the one or more weight inserts 22 may be configured, without limitation, with a slot head ( FIG. 5A ), a custom head such as a head having one or more spanner holes ( FIG. 5B ), a Phillips head ( FIG. 5C ), a hex socket head ( FIG. 5D ) or with any other similar configuration.
[0033] Referring to FIG. 6 , a top plan view of an improved bowling ball 10 a in accordance with an alternate embodiment of the present invention is shown. According to this alternate embodiment, the bowling ball 10 a includes a spherical outer shell 12 , a weighted inner core (not shown), and a first set of finger and thumb holes ( 14 , 16 and 18 ), a second set of finger and thumb holes ( 14 a , 16 a and 18 a ), and two or more weight holes ( 20 and 20 a ) drilled into the outer shell of the bowling ball 10 a . Each of the first set of finger and thumb holes ( 14 , 16 and 18 ), second set of finger and thumb holes ( 14 a , 16 a and 18 a ), and weight holes ( 20 and 20 a ) are arranged along the outer perimeter of the bowling ball 12 and extending radially inward therein forming an open cavity therebetween. The bowling ball 10 a includes one or more weight inserts 22 which plug corresponding weight holes 20 and are proximate to the first set of figure and thumb holes ( 14 , 16 and 18 ). The bowling ball 10 a also includes corresponding weight inserts 22 which plug the second set of figure and thumb holes ( 14 a , 16 a and 18 a ) and weight hole 20 a.
[0034] Each of the weight inserts 22 substantially cover and close corresponding weight holes ( 20 and 20 a ) and second set of finger and thumb holes ( 14 a , 16 a and 18 a ) such that in their operational positions, the perimeter surface of the bowling ball has substantially the same condition as if the weight holes ( 20 and 20 a ) and second set of finger and thumb holes ( 14 a , 16 a and 18 a ) were not present. In operational use, the weight inserts 22 may be used to plug either the first set of finger and thumb holes ( 14 , 16 and 18 ) and weight hole 20 , or the second set of finger and thumb holes ( 14 a , 16 a and 18 a ) and weight hole ( 20 a ), thereby producing alternate weighting options that may be adjusted to achieve optimum performance of the bowling ball 10 a . Obviously, other sets of plugged finger and thumb holes are possible within the scope of the present invention.
[0035] In operation, one or more weight holes arranged on the outer perimeter 12 of the bowling ball 10 and extending radially inward therein are drilled forming an open cavity therebetween. One or more weight inserts 22 having an appropriate weight is selected and inserted into corresponding one or more weight holes 20 using, without limitation, a wrench, a screwdriver, a drill or the like. The one or more weight inserts 22 are seated into their respective operational positions such that they substantially cover and close the corresponding one or more weight holes 20 . The one or more weight inserts 22 are configured and sized such that they are held in place by means of frictional engagement. By inserting differently weighted positive or negative top, bottom and/or side weight inserts 22 into their operational positions, the top, bottom and/or side weight may be adjusted for the corresponding bowling ball. Thereby, when and how the ball will hook and/or the snap of the ball at the backend of the lane may be adjusted.
[0036] While the present invention has been described with reference to one or more particular embodiments, those skilled in the art will recognize that many changes may be made thereto without departing from the spirit and scope of the present invention. Each of these embodiments and obvious variations thereof is contemplated as falling within the spirit and scope of the claimed invention, which is set forth in the following claims.
[0037] Obviously, many other modifications and variations of the present invention are possible in light of the above teachings. The specific embodiments discussed herein are merely illustrative, and are not meant to limit the scope of the present invention in any manner. It is therefore to be understood that within the scope of the disclosed concept, the invention may be practiced otherwise then as specifically described. | A system and method for variably altering the dynamics of a bowling ball. The system includes a bowling ball, one or more weight holes arranged along the outer perimeter of the bowling ball and extending radially inward therein forming an open cavity therebetween, and one or more removable weight inserts configured to be inserted into and frictionally engage the respective weight holes during an operational use thereof such that the one or more removable weight inserts substantially cover and close the one or more weight holes. Each of the removable weight inserts have a positive or negative weight effect and include indicia designating the weight of the respective removable weight insert. | 0 |
BACKGROUND OF THE INVENTION
A prior art device of this kind comprises a number of fibers which are fixedly supported at one end and extend towards and engage by means of contact surfaces the surface from which the dirt and contaminants shall be removed, the fibers being adapted to remove the dirt and contaminants while being translationally moved in relation to said surface. A device of this kind can be utilized as a so called brush seal, the device being thereby positioned in a space between two surfaces being moved in relation to each other for preventing dirt and contaminants to enter the space and removing dirt having already entered this space. A brush seal of this kind is used for example, as an integrated additional seal in a shaft seal device, the primary seal being constituted by a radial or axial sealing ring of elastomeric material, for example rubber, having a sealing lip sliding along a counter surface and sealing against for example oil or grease. By preventing dirt and contaminants from reaching the sealing lip the additional seal provides for an improved total sealing effect of the sealing device as well as an extended life of the primary seal.
In a sealing device of the brush seal type it is usually desirable that the device displaces the dirt and contaminants in a direction transversely of the direction of the relative movement between the fibers and the surface from which the dirt and contaminants are to be be removed. In sealing devices of the kind described, wherein the brush seal constitutes an additional seal it is of course desirable to displace the dirt and the contaminants laterally away from the primary seal. However, such controlled displacement of the dirt and contaminants is not possible in prior art sealing devices of the kind comprising fibers engaging and being moved in relation to the surface from which the dirt is to be removed.
SUMMARY OF THE INVENTION
The object of the present invention is to povide a device of the type mentioned above having the capacity of displacing the dirt away from the device laterally in respect of the relative movement between the fibers and the surface from which the dirt shall be removed. In order to comply with this object, there is according to the invention provided a device for removing dirt and contaminants from a surface comprising fibers having conveyor surfaces extending obliquely to the direction of relative movement between the fibers and the surface from which the dirt and contaminants are to be removed, said conveyor surfaces being adapted to displace the dirt and contaminants away from the surface in a direction transversely of the direction of the relative movement.
In a prefered embodiment of the device according to the invention, each fibers has at least two conveyor surfaces adapted to be in operation at each one direction of opposite directions of relative movement between the fibers and the surface. In this embodiment, it is preferred that the fibres are adapted to be displaced between two different positions on reversal of the direction of relative movement between the fiber and the surface so that different conveyor surfaces are in operation in different positions of the fibers.
In the prefered embodiment the fibers displace the dirt and contaminants away from the surface in the same conveyance direction irrespective of the relative movement between the fibers and the surface taking place in one or the other of the two opposite directions. In an axial sealing device, wherein the device according to the present invention constitutes an additional seal, this provides the effect that the additional seal displaces the dirt away from the primary seal irrespective of the rotational direction of the shaft in relation to the ambient construction.
In order to provide that the fibers take different positions in which different conveyor surfaces are in operation the fibers can be designed so that the contact surfaces of the fibers engaging the surface from which the dirt or contaminants shall be removed are of longitudinal shape, the two conveyor surfaces of the fibers being constituted by the sides of the portions of the fibers adjacent the contact surfaces. Furthermore, the fibers are designed so that they present at one end of the contact surface a greater resistance against displacement by the surface when the surface is moved in relation to the fibers that at the other end of the contact surface. The fibers are fixedly supported in such a way that they strive to take a position in which the longitudinal axis of the contact surfaces of the fibers extends substantially perpendicular to the direction of relative movement between the fibers and the surface from which the dirt is to be removed. When the fibers are designed in this way, the portions of the fibres adjacent the contact surface will take the two different positions in which different conveyor surfaces are in operation dependent on the direction of the relative movement between the fibers and the surface.
The invention is described in the following with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is an axial section of a portion of a shaft sealing device in which the device according to the present invention is included as an additional seal.
FIG. 2 shows an embodiment of the device according to the invention on an enlarged scale.
FIGS. 3a, 3b and 3c are cross-sections take along line III--III in FIG. 2 and show the device according to the present invention in different operational positions.
FIG. 4 is a view corresponding to FIG. 2 showing another embodiment of the device according to the present invention.
FIGS. 5a, 5b and 5c are cross-sections taken along line V--V in FIG. 4 and show the device according to the invention in different operational conditions.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 there is shown a rotatable shaft 2 extending through an opening in a wall 4. In order to seal the spaces 6 and 8 at opposite sides of the wall 4, there is in the clearance space between the outer surface of the shaft 2 and surface defining the opening in the wall 4 provided an axial sealing device of the radial type. The axial sealing device comprises a primary seal in the form of radial sealing ring 5 and a brush seal 12 which constitutes a device according to the present invention. The radial sealing ring 5 consists of rubber and has a fastening portion 14 by means of which the radial sealing ring 10 is connected with the wall 4. The fastening portion 14 is provided with a reinforcing ring 16 consisting of metal. The radial sealing ring 10 has a sealing portion 18 comprising a sealing lip 20 which is radially forced against the cylindrical outer surface of the shaft 2 by means of a spring 22.
The device according to the present invention constituted by a brush seal 12 has the object of preventing dirt and contaminants present in the space 8 from reaching the sealing lip 20. Thereby, there is provided an improved sealing action of the sealing device and there is also provided a longer life of the sealing ring 10 because of the fact that grinding particles are prevented from wearing the sealing lip 20. In accordance with the invention, the brush seal 12 is designed so that the dirt particles are displaced in a direction away from the sealing device irrespectively of the rotational direction of the shaft 2. This is provided by a special design of the fibers 24 of the brush seal 12 according to the present invention. The design of the fibers of two different embodiments of the device appears from FIGS. 2 and 3, and FIGS. 4 and 5, respectively. One end of the fibers is fixedly supported by a surface 26 of the sealing ring 10. At their opposite end from the surface 26, the fibers 24 engage the cylindrical outer surface of the shaft 2. Thus, when the shaft is rotated the fibers are in sliding contact with the cylindrical outer surface of the shaft by means of their contact surfaces in order to remove the dirt from the surface of the shaft.
According to FIG. 2 the fibers 24a are fixedly supported by the sealing ring 10 at the surface 26 at their upper ends while the fibers extend from the surface 26 substantially perpendicular towards the surface 2a, which represents the outer surface of the shaft 2. The fibers 24a engage the surface 2a at their free end surfaces by means of contact surfaces 28.
FIG. 3a shows the sectional shape of the fibers 24a, the sectional shape corresponding to the shape of the contact surfaces 28. In the embodiment according to the invention shown in FIGS. 2 and 3, the fibers have substantially drop shaped cross section and contact surface 28. The fibers 24a are fastened to and supported by the surface 26 so that the longitudinal and symmetrical axis 30 of the fibers is in the relaxed condition thereof extending substantially perpendicular to the intended direction 31 of the relative movement between the surface 2a and the fibers 24a. Adjacent the contact surface 24 the fibers form oblique conveyor surfaces 32 having the object of removing dirt and contaminants from the surface 2a when the surface 2a and the fibers are moved in relation to each other.
When the surface 2a is moving in the direction shown by the arrow 34 in FIG. 3b, the fibers will, at their contact surfaces 28 take the position shown in FIG. 3b, in which the conveyor surface 32 which is contacted by dirt particles on the surface 2a, takes an angular position providing that the dirt particles on the surface 2a will be displaced away from the surface 2a in the direction shown by the arrow 36, i.e. in a direction away from the radial sealing ring 10. The shown position of the contact surface 28 is provided by the fact that the fibers 2a present a greater resistance against displacement at the end 38 of the contact surface 28 than at the end 40 thereof. This difference is of course due to the fact that the section of the fibers is wider at the end 38 than at the end 40.
As appears from FIG. 3c, the fibers 24a assume a position rotated from the position according to FIG. 3b in the counter-clockwise direction when the surface 2a is moved in the direction shown by the arrow 42. In this position, the conveyor surface 32 at the opposite side of the fibers is in operation for displacing the dirt from the surface 2a. Because of the changing of the rotational position of the fibers there is obtained the same direction of movement of the dirt, i.e., away from the radial sealing ring 10, in spite of the fact that the direction of movement of the surface 2a has been reversed.
In the embodiment according to the present invention shown in FIGS. 5a, 5b and 5c, the fibers 24b have greater length than the distance between the surface 26 and the surface 2a. Therefore, the fibers 24b will assume a position in which the fibers have at their free ends a deflected portion 44. Thus, the outer surface of the deflected portion of the fibers will constitute the surface 28b of the fiber contacting the surface 2b. Thereby the sides of the deflected portion 44 will constitute the conveyor surfaces 46 of the fiber. It is realized that the deflected portion will present less resistance against displacement at its free end 48 than at the opposite end 52 of the deflected portion 44 when the surface 2a is moved in the direction according to the double arrow 50. Thereby, the fibers 24b will act in the same way as the fibers 24a when the surface 24b is moved in opposite directions in order to transport dirt from the surface 2b in the direction shown by the arrow 54 irrespective of the rotational direction of the surface 2b. In the embodiment according to FIGS. 5a, 5b and 5c the cross section of the fibers is triangular providing that the deflected portion 44 forms a flat contact surface 28b against the surface 2b. It is, of course, possible to design the cross section of the fibers in the desired way to provide the desired function. For example, it is possible to provide the contact surface 28b with grooves or the like for constituting a number of scraping edges at the contact surfaces.
The invention can be modified within the scope of the following claims. Thus, the invention can be utilized in many other applications other than in sealing devices. It is also possible to provide further modified embodiments of the fibers while maintaining the conveyor effect constituting the basic concept of the invention. | A device for removing dirt and contaminants from a surface comprises a number of fibres (24) fixedly supported at one end and extending towards and engaging at a contact surface (28) the surface (2) from which the dirt and contaminants shall be removed. The fibres (24) have conveyor surfaces (32) extending obliquely in relation to the direction of relative movement between the fibres and said surface (2), said conveyor surfaces being adapted to move the dirt and contaminants away from said surface in direction transversely to the direction to said relative movement between the fibres (24) and said surface (2). | 5 |
FEDERALLY SPONSORED RESEARCH STATEMENT
[0001] Not Applicable
REFERENCE TO SEQUENCE LISTING, A TABLE OR A COMPUTER PROGRAM LISTING
[0002] Not applicable
BACKGROUND OF THE INVENTION
Field of the Invention
Prior Art
Brief Summary of the Invention
[0003] It is the objective of the inventive, MOP system, to create and store complete, accurate, and effective Methods of Procedure (MOPS) that defines the work and timing of said work to be performed in a critical infrastructure environment. Additionally, the MOP System, will guide the data entry and data retrieval from a variety of associated system databases based on MOP Creator guided input and two-way interaction. Additionally, the inventive system manages the approval process for the work to be performed. The inventive system uses machine based algorithms to automate the creation of distributable MOP documents and tickets to interested parties impacted or affected by the MOP.
[0004] A Method of Procedure (“MOP”) is a formalized document that describes maintenance procedures that will be performed by specific people, on designated assets in a defined location, and when that work will be performed over a specific period of time. In the preferred embodiment, these assets are located in critical infrastructure environment and facility that provide continuous essential services to a set of interested parties, including customers and consumers of said services.
[0005] While a Method of Procedure does not have a rigid definition of structure, definition, or format, a well-constructed MOP, and the MOP in the preferred embodiment, contains the following elements:
Unique MOP Identifier Location: Address of the facility, specific rooms or places in that location Start and End times of work to be performed Work Risk Level Submitter information: Name, Phone Number and Email Type: Corrective Maintenance, Engineering work, Preventive Maintenance, etc. Status: Pending, Approved, In Progress, Completed, etc. Critical Contacts: MOP Author, Consultants, MOP Manager, Approvers, Interested Parties, Emergency Personnel, Vendors, etc. Scope and Purpose: Written description of the work and the purpose of the work to be performed Responsibilities List: A list of persons and the actions they will be taking for the duration of the MOP Tasks:
A list of pre-tasks that may have to performed prior to the work being performed Work Phases: The actual work being performed on specific assets, along with the steps that would constitute that task
Back-out plans: A list of steps and tasks that would be followed if for any reason the defined tasks fail to work as designed Documents: Any pertinent documents to the work to be performed (e.g. Equipment manuals, diagrams, maps, protective clothing, etc.
[0021] The inventive system is used by a MOP creator/submitter. The inventive system guides the MOP creator through all of the required components of the MOP and ensures the completeness of the MOP. Additionally, the inventive system provides simplified, intelligent access and retrieval of data stored in multiple, associated systems that contain the information related to contacts, tasks, work phases and other components of the MOP. The inventive system also allows for free-form data entry when other systems cannot provide all of the required information.
[0022] Proposed completed MOP is routed to a set of approvers, whose role is to review the contents of the MOP for effectiveness, review the MOP for completeness, and either approve or reject the MOP as written. If a MOP is rejected it can be modified for resubmittal. If a MOP is approved, interested parties are notified of the approval and notified to varying degrees of the MOP contents. In the preferred embodiment a work/mop ticket is automatically created by the MOP System in order to maintain a record of the work and notify impacted interested parties. The inventive system also knows how the customer is integrated into the critical infrastructure environment and includes in the notification the specific customer equipment that are impacted by the MOP.
DESCRIPTION OF FIGURE
[0023] The FIGURE: A comprehensive schematic of the MOP Management System and interaction model with Associated System Databases and Interested Parties.
DETAILED DESCRIPTION OF THE INVENTION
Explanation of Invention Definitions and Explanation of Terms Specific to the Disclosure
[0024] MOP Management System 10 (“MOP System 10 ”): MOP System 10 , the invention, is a bespoke application system, programmed in a commercially available programming language, consisting of the following components: MOP Manager Interface 11 , MOP Database 12 , MOP & Mini-MOP Creator 13 , MOP Approval Processor 14 , Affected Customer Analyzer 16 and Impacted Asset Analyzer 15 . MOP System 10 elicits input from MOP Creator 21 , gets additional information from Impacted Asset Analyzer 15 and Affected Customer Analyzer 16 , then creates a MOP document, a smaller notification document called a Mini MOP. The MOP and Mini-MOP are stored in MOP Database 12 . MOP System 10 use MOP Approval Processor 12 to manage MOP Approver 22 , then uses Notification Engine 51 to automatically communicate to Interested Parties 20 .
[0025] MOP Manager Interface 11 : A bespoke application component, programmed in a commercially available programming language. It elicits guided input from MOP Creator 21 through a web interface in order to complete the information gathering required for a MOP. MOP Manager Interface 11 provides the visual application component to MOP System 10 .
[0026] MOP Database 12 : A commercially available relational database is used to define a bespoke set of tables and relational database structures that stores all information required for a complete MOP document and the MOP System 10 .
[0027] MOP & Mini-MOP Creator 13 : A bespoke application component, programmed in a commercially available programming language. It creates two documents of standard industry types (PDF, Microsoft Word Doc, etc), in a consistent format for consumption by Interested Parties 20 . MOP document contains all the information collected through MOP Manager Interface 11 and other components of MOP System 10 . Mini-MOP 53 contains a subset of information collected through MOP Manager Interface 11 to be presented to Customer 23 .
[0028] MOP Approval Processor 14 : A bespoke application component, programmed in a commercially available programming language. A MOP created in MOP System 10 by MOP Creator 21 , must be approved by a MOP Approver 22 , who is not the same person as MOP
[0029] Creator 21 : MOP Approver 22 is one or more persons assigned to review MOPs for one or more critical infrastructure environments. MOP Approval Processor 14 ensures that the right MOP Approver 22 is chosen for a particular MOP and tracks whether the MOP has been accepted or rejected. Once accepted MOP Approval Processor 14 communicates to Notification Engine 51 that a Ticket 52 and Mini MOP 53 can be sent to Interested Parties as determined by Affected Customer Analyzer 16 and retrieved contact information from Contacts Database 41 .
[0030] Impacted Asset Analyzer 15 : A bespoke application component, programmed in a commercially available programming language. Impacted Asset Analyzer 15 extracts the data collected by MOP Manager Interface 11 to identify the assets undergoing work. Those assets are passed to Affected Customer Analyzer 16 .
[0031] Affected Customer Analyzer 16 : A bespoke application component, programmed in a commercially available programming language. Affected Customer Analyzer associates those assets extracted by Impacted Assets Analyzer 15 to Customer 13 assets stored in Panel Schedule Database 43 . It also uses computer programming rules that know the preferred embodiment of the data center in order to associate equipment to a customer for equipment not stored in Panel Schedule Database 43 . This component identifies the list of Customers 13 that will be notified using Notification Engine 51 .
[0032] Associated Systems Databases 40 : A series of database maintained by other systems related to data center operations, the preferred embodiment. These include Contacts Database 41 , CMMS Assets and Work Orders database 42 and Panel Schedule Database 43 .
[0033] Contacts Database 41 : A commercially available relational database is used to define a bespoke set of tables and relational database structures that store information about Interested Parties 20 and the different means to contact them (e.g. eMail, Phone, Mobile Phone, etc.)
[0034] CMMS Assets and Work Orders Database 42 : A commercially available relational database is used to define a bespoke set of tables and relational database structures for a CMMS (Computerized Maintenance Management System) system that is a proprietary version of commercially available software. The CMMS system is responsible for storing information with regards to assets. It manages work to be done within the Data Center as it pertains to those assets. Typical work defined in the system includes maintenance on asset equipment and customer requests for power.
[0035] Panel Schedule Database 43 : A bespoke set of tables in a commercially available database system, used for the tracking of circuit breaker positions and availability and Customer 23 assigned to the circuit breaker.
[0036] DCIM Database 44 : (DCIM: Data Center Information Management System) A bespoke set of tables in a commercially available database system, used for the monitoring and information gathering related to a data center. With respect to the invention, the database stores the electrical diagram for the data center which is called the One-Line 56
[0037] Notification Engine 51 : A bespoke application integrated into the inventive system. It uses industry standard protocols for outbound communications including but not limited to SMS, SMTP, etc. Notification center 6 uses templates for communication that draws information from various other systems in the invention as outlined below.
[0038] Ticket 52 : A collection of grouped information, stored in a bespoke application (ticketing system) used for recording the status of a set of activities. Ticket 52 is accessible through a ticketing system interface and other communications protocols. In the preferred embodiment, the activities and status thereof pertain to the work tasks defined in MOP System 10 .
[0039] Mini-MOP 53 : A document of standard industry types (PDF, Microsoft Word Doc, etc), in a consistent format for consumption by Interested Parties 20 . Mini-MOP 53 contains a subset of information collected through MOP Manager Interface 11 to be presented to Customer 23 .
[0040] User Guided Input 54 : An interaction model between MOP Creator 21 and MOP Manager Interface 11 . The interaction model is input provided by MOP Creator 21 to prompts by MOP Manager Interface 11 . Inputs from MOP Creator may change the prompts and availability of data from MOP Manager Interface 11 .
[0041] Work Completion & MOP Update 55 : The interaction and process model between Interested Parties 20 and MOP System 10 as it applies to the status of MOPs in MOP System 10 .
[0042] One Line 56 : The systematic representation of an electrical system. Stored for the purposes of the inventive system in DCIM Database 44 .
[0043] MOP 57 : A Method of Procedure (“MOP”) is a formalized document that describes maintenance procedures that will be performed on assets and when that work will be performed. In the preferred embodiment, these assets are located in critical infrastructure environment and facility, meaning facilities that provide essential services, all the time, to a set of interested parties, or consumers of said services.
[0044] MOP Creator 21 : Person responsible for interacting with MOP System 10 to enter data.
[0045] MOP Approver 22 : Person, explicitly not MOP Creator 21 , responsible for reviewing the MOP for completeness and accuracy.
[0046] Customer 23 : Person or persons who use the services impacted by work performed in the critical infrastructure facility.
[0047] NOC 24 (“Network Operations Center): A person or persons responsible for coordinating activities and Interested Parties 20 defined by the MOP.
[0048] For the purposes of this disclosure a critical infrastructure environment is defined as a constructed system that provides uninterrupted services. A data center is considered to be a specific form of a critical infrastructure environment that provides the service of power and cooling to computer equipment.
[0049] In the instance of the present invention, MOP Creator 21 interacts with MOP System 10 through MOP Manager Interface 11 . MOP Manager Interface 11 guides the user through a set of requirement data that constitute MOP 57 . In the preferred embodiment, relating to critical infrastructure environments and facilities, particularly data centers, MOP System 10 requires:
General MOP Information: MOP Title, Activity Types (corrective maintenance, preventive maintenance, engineering tasks, etc.), Site/Location of Work, Risk Level, affected areas and acknowledgement of work standards for critical environments. Attachments: Addition of critical documents required to perform work in the site/location. In the preferred embodiment, these include backout plans, work phases, Original Equipment Manufacturer manuals, electrical switching tag orders, etc. Contact Information: Information pertaining to persons in different roles as it pertains to the MOP and the work to be performed. Mandatory and non-mandatory personnel are listed, with mandatory personnel as a requirement. These contacts: MOP Author 21 , MOP Manager, Network Operations Center 24 , Emergency/Safety personnel, etc. Scope and Purpose: Detailed description of work to be performed, purpose, expected outcomes, equipment. Responsibilities: A contact (Interested Parties 20 , maintenance vendors, etc.) associated with a description of their responsibility with respect to work. Pre-Tasks: Responsible Party, Description of the pre-task and protective gear assignment. Work Phases: One or more descriptions of work and the steps required to perform the work. Work Phases may be selected from CMMS Assets and Work Orders 42 , or manually entered by MOP Creator 21 . Back Out Plans: A description of effort or work that must occur if any part of the MOP process fails.
[0058] Guided, Intelligent and Automated MOP Creation: Based on inputs from MOP Creator 21 , MOP System 10 makes intelligent selections as to the data that can come from Associated System Databases 40 to be used by the system, and for data that is required by MOP System 10 . For example, selection of Site/Location by MOP Creator 21 allows MOP System 10 to automatically filter work orders from CMMS Assets and Work Orders 42 that are only for that Site/Location. MOP System 10 asks only for work orders that have certain statuses, for example the status of open. Another example, in the preferred embodiment of a critical infrastructure environment such as a data center, work performed on electrical equipment requires a document called Switching Tags. This document is not required for work on mechanical equipment. The inventive system intelligently prompts for required information from MOP Creator 21 based on equipment type. In this way, the inventive system ensures accuracy and completeness of MOP 57 .
[0059] MOP System 10 integrates with Associated System Databases 40 to auto-populate required MOP 57 information. MOP Creator 21 must specify responsible parties for work to be performed. Work can include pre-tasks, work, post-work tasks, and ancillary tasks. All work must designate a responsible person and their contact information. MOP System 10 presents contacts from CMMS Assets and Work Orders Database 42 , Contacts Database 41 , and offers pre-filtered choices for MOP Creator 21 to choose from. MOP System 10 also allows MOP Creator 21 to enter other responsible parties not stored in Associated System Databases 40 . Again, choices are pre-filtered based on Site/Location, or the specific assets associated to the work.
[0060] MOP Creator 21 may select one or more Work Phases from CMMS Assets and Work Orders 42 or Work Phases may be manually entered. A selection from CMMS Assets and Work Orders 42 , auto-populates MOP 57 with information such as Work Phase Title, Responsible Party, Planned Date and Task Steps. MOP Creator 21 has only to fill in the planned start time and duration for that Work Phase. If the data is available MOP System 10 can retrieve from CMMS Assets and Work Orders 42 a standard amount of time for pre-defined work. MOP System 10 ensures data accuracy by retrieving all relevant information automatically from Associated System Database 40 . If MOP Creator 21 chooses to manually enter a Work Phase, the MOP System 10 ensures that all required fields listed above are completely filled in.
[0061] MOP System 10 automatically orders the work phases according to the planned start time datum so that MOP 57 contains an accurate description of work phases across time.
[0062] Data Entry Post Processing: After MOP System 10 guides MOP Creator 21 through the creation of MOP 57 and before MOP System 10 saves MOP 57 to MOP Database 12 , MOP and Mini-MOP Creator 13 takes two post-processing steps. First MOP & Mini-MOP Creator 13 programmatically calls Impacted Assets Analyzer 15 to determine, extract and list which assets in the critical infrastructure environment are impacted. These assets were identified by MOP Creator 21 's selection of work phases from CMMS Assets and Work Orders 42 . In the preferred embodiment of a data center, and specifically related to electrical power in the data center, the asset list extracted by Impacted Assets Analyzer 15 is programmatically queried against One-Line 56 stored in DCIM Database 44 to find any other electrical equipment assets downstream (“the flow of current through the system to a customer asset”) of the assets being worked on, including the circuit breakers data stored in Panel Schedule Database 43 . Panel Schedule Database 43 stores not only the circuit breaker data, but Customer 23 associated with that circuit breaker. Impacted Assets Analyzer 15 programmatically passes all impacted assets to Affected Customer Analyzer 16 which in turn queries Panel Schedule Database 43 for the list of Customers 23 . Affected Customer Analyzer programmatically communicates selected Customers 23 to MOP & Mini-MOP Creator 13 which in turn stores that information in MOP Database 12 .
[0063] Approvals and Notifications: MOP Management System 10 , having completed the data gathering stage, proceeds to approvals and notifications. Each critical infrastructure environment is assigned to a hierarchy of MOP Approvers 22 . Based on the critical environment selection made by MOP Creator 21 , MOP Approval Processor 14 uses Notification Engine 51 to create a communication to assigned MOP Approver 22 . If MOP Approver 22 doesn't respond to MOP Approval Processor 14 in a specified period of time, a different MOP Approver 22 may be selected. Never may MOP Approvers 22 be the same as MOP Creator 21 . MOP Approver 22 accepts or denies MOP 57 using MOP Manager Interface 11 . A rejected MOP 57 is routed by MOP Approval Processor 14 back to MOP approver 22 for modification.
[0064] MOP 57 accepted by MOP Approver 22 triggers MOP Manager System 10 to use Notification Engine 51 to create three separate communiques. Ticket 52 is created and communicated to Interested Parties 20 and specific Customers 23 as determined by the Affected Customer Analyzer 16 as described previously. Ticket 52 serves as a common vehicle for status updates to Interested Parties 20 . Mini-MOP 53 , a subset of MOP 57 information pertinent to Customer 23 , is communicated through Ticket 52 . The last communication is Calendar Event 52 which is submitted to a commercially available calendaring system (e.g. Microsoft Outlook, Microsoft Exchange, Google Calendar, etc.). Each critical infrastructure environment has its own calendar, and Calendar Event 52 is sent to the specific critical infrastructure environment calendar specified by MOP Creator 21 in MOP 57 .
[0065] MOP Management System 10 must be updated by MOP Creator 21 with the status of MOP 57 . A completed MOP 57 is retained in MOP Database 12 and is made un-editable so that MOP 57 stands as a final and unalterable record of events in the critical infrastructure environment. MOP Manager System 10 may be used to search and retrieve MOPs 57 from MOP Database 12 .
[0066] MOP Templates: MOP Management System 10 allows MOP Creator 21 to use a previously-created MOP 27 to be the starting point for a new MOP 27 . Because the same work may be performed across different critical infrastructure environments, many of the data associated with MOP 27 may be identical. MOP Creator 21 can change as appropriate the MOP 27 template to fit the need but significantly reduce the data input process. MOP Management System 10 ensures that an identical MOP 27 may not be created. | A system that documents work to be performed at a specific location over a specific period of time by specific personnel on designated equipment by guiding a human user to create a unique, accurate, and complete document. | 6 |
FIELD OF THE INVENTION
This invention relates to the separation of racemic mixtures of optical isomers and other similar molecules into their separate isomeric components. More specifically, the present invention relates to methods for the separation of optical isomers employing differential partitioning of the molecules between high and low density water microdomains.
BACKGROUND OF THE INVENTION
Most biomolecules have at least one asymmetric carbon atom and, therefore, exist as optical isomers, known as enantiomers, which are mirror images of each other. Many synthetic drugs also contain asymmetric carbon atoms. However, since their synthesis is abiotic, the synthetic product is a racemic mixture consisting of equal concentrations of enantiomers. Since proteins and other biologically active molecules have chiral centers at which the molecules act, enantiomers generally have different biological actions, with one enantiomer being more effective than the other. In some cases the enantiomers appear to be antagonistic.
One solution to this problem is to carry out syntheses which result in a single enantiomer, such as those performed by Sepracor Inc. (Marlborough, Mass.). However, such methods are often tedious and expensive. The other solution is to resolve the racemic mixture into separate isomeric compounds. This is difficult to achieve on a preparative scale, with methods presently used for such separations generally relying on specific interactions of the enantiomers on a chiral column. While many drugs are now resolved into their separate isomers during synthesis, there remains a need for a simple and inexpensive method for the resolution of any racemic mixture.
SUMMARY OF THE INVENTION
The present invention provides methods for the separation of enantiomers in a racemic mixture by differentially partitioning the enantiomers into regions of low density water and high density water abutting a porous surface. In preferred embodiments, the porous surface comprises a matrix of small-pored beads. Preferably, the beads comprise pores less than 5 nm in diameter, more preferably less than 3 nm in diameter and most preferably between 1 and 3 nm in diameter.
Matrices of small-pored beads, such as polyamide gels and ion exchange resins, contain separated microdomains of high and low density water. Solutes can be classified into chaotropes or kosmotropes according to their partitioning between these microdomains. Chaotropes partition selectively into low density water and induce high density water, while kosmotropes partition into high density water and induce low density water. In order to separate chaotropes from kosmotropes, the microdomains of high and low density water must be stabilized by balancing chaotropes against kosmotropes and preventing creation of osmotic pressure gradients between the microdomains. When the microdomains are stabilized, the matrix, or gel, is also at its maximum volume. At the particular solution composition at which this balance is achieved, chaotropes, such as D-glucose and L-amino acids, are retained on a polyamide gel and can then be eluted using a solution of a strong chaotrope which breaks down low density water.
More specifically solutes which can break down low density water in a polyamide gel, and can therefore be used to elute chaotropes, include the chaotropes K + , Rb + , Cs + , HCO 3 − , H 2 PO 4 − , NO 3 − , HSO 4 − , and tetramethyl ammonium ion. Solutes which stabilize low density water in a polyamide gel, and which can therefore be used to elute kosmotropes, include Mg 2+ , Ca 2+ , H + , Li + , Na + , SO 4 2− , HPO 4 2− , F − , OH − and hydrophobic solutes such as ethanol, propanol, benzyl alcohol and butanol.
Small-pored cation and anion ion exchange resins contain microdomains of both high and low density water. The stability of these microdomains in cation exchange resins increases with change of counter ion from Na + , Li + or H + to K + , Rb + or Cs + and especially to Ca 2+ or Mg 2+ . The stability of the microdomains in anion exchange resins increases with change of counter ion from OH − or F − to Cl − , Br − or I − and especially to SO 4 2− . Chaotropes, such as L-amino acids and D-glucose, can be eluted from ion exchange resins with aqueous solutions of kosmotropes, such as Mg 2+ , Ca 2+ , H + , Li + , Na + , SO 4 2− , HPO 4 2− , F − and OH − and hydrophobic solutes such as ethanol, propanol, benzyl alcohol and butanol. Kosmotropes, such as D-amino acids and L-glucose, can be eluted from ion exchange resins with solutions of chaotropes, such as K + , Rb + , Cs + , HCO 3 − , H 2 PO 4 − , NO 3 − HSO 4 − , and tetramethyl ammonium ion. In addition, all solutes, both kosmotropic and chaotropic, can be eluted from ion exchange resins by neutralizing the resins.
In one aspect, the present invention thus provides a method for separating a mixture of a kosmotropic enantiomer and a chaotropic enantiomer comprising: (a) providing a matrix of small-pored beads; (b) stabilizing microdomains of high density water and low density water within the matrix; (c) contacting the stabilized matrix with the mixture of enantiomers; (d) contacting the matrix with a solution that breaks down low density water in the matrix, wherein the chaotropic enantiomer is eluted from the matrix; and (e) contacting the matrix with a solution that stabilizes low density water in the matrix, whereby the kosmotropic enantiomer is eluted from the matrix.
The above-mentioned and additional features of the present invention and the manner of obtaining them will become apparent, and the invention will be best understood by reference to the following more detailed description, read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the applicants' invention will be described with reference to the drawings, in which:
FIG. 1 shows the elution of D- and L-glucose from a Bio-Gel P-6 (BioRad Laboratories, Richmond, Calif.) column. 1 g of dry gel was pre-treated with 0.2 M n-BuOH for 24 h. A 1 ml sample (40 mM DL-glucose, 0.2 M BuOH) was then put on the column and eluted with 0.2 M BuOH.
FIG. 2 illustrates the elution of D- and L-lysine from a Bio-Gel P-6 column. 1 g P-6 gel was pre-treated with 50 mM n-BuOH for 21 h; 1 ml of 20 mM L-lysine, 20 mM L-lysine, and 40 mM n-BuOH containing 14 C-L-lysine was put on the column and eluted with 15 ml of 50 mM n-BuOH, followed by 20 mM NH 4 HCO 3 . Total lysine was determined from its absorbance relative to that of 50 mM BuOH at 210 nm, using a standard curve of lysine in 50 mM BuOH, and diluting samples, where necessary, in 50 mM BuOH. L-Lysine was determined by scintillation counting and D-lysine was determined by difference. Following addition of NH 4 HCO 3 , total lysine could not be determined. This pattern of elution was reproducible on the same batch of gel.
FIG. 3 illustrates the elution of D- and L-lysine from a different batch of Bio-Gel P-6. The method employed was the same as that for FIG. 2 except that the concentrations of D- and L-lysine were 10 mM and the second eluting solution was 50 mM KH 2 PO 4 . By making corrections for (i) the effects of changing solution composition on the absorbance of lysine at 210 nm, and (ii) NH 3 eluted from the gel, total lysine was measured up to 30 ml. These results were highly reproducible on this batch of gel. Both D- and L-lysine were totally recovered.
FIG. 4 illustrates the elution of K + -DL-glutamate and of K + -L-glutamate from Dowex 50Wx16 after 12 days of preequilibration with water. L-glutamate was labeled with 14 C, and DL-glutamate was estimated by absorption at 210 nm.
FIG. 5 illustrates the elution of K + -D-glutamate and K + -L-glutamate from Dowex 50Wx16, obtained by difference from FIG. 4 .
FIG. 6 illustrates the elution of K + -D-glutamate and K + -L-glutamate from Dowex 50 W in its K + form.
FIG. 7 illustrates the elution of DL chloroquine phosphate from a Bio-Gel P-6 column. 1 g Bio-Gel P-6 was pretreated with water overnight. 1 ml 20 mM DL chloroquine phosphate was put on the gel and eluted with 20 ml water followed by 50 ml of 50 mM NH 4 NO 3 .
FIG. 8 illustrates the effect of graded concentrations of ethanol on the external pH of 5 mM potassium phosphate (initially pH 7).
FIG. 9 illustrates the separation of D- and L-glucose in 1 g of washed Bio-Gel P-6 mixed for 18 hours in 7.5 ml solutions containing 5 mM tetramethyl ammonium chloride, 10 mM D-glucose, 10 mM L-glucose, 3 mM sodium azide and graded concentrations of ethanol.
FIG. 10 illustrates the separation of D- and L-glucose in a Bio-Gel P-6 gel after 2 days of mixing in solutions containing 20 mM ethanol, 3 mM sodium azide, 10 mM D-glucose, 10 mM L-glucose and graded concentrations of tetramethylammonium chloride.
FIG. 11 illustrates the separation of D- and L-glucose in 0.5 g of a Bio-Gel P-4 gel mixed for 4 days at room temperature in 4 ml of solutions containing 5 mM potassium phosphate, pH 7, 3 mM sodium azide, 20 mM L-glucose, 20 mM D-glucose, 2 mM benzyl alcohol and graded concentrations of ethanol.
FIG. 12 illustrates the separation of D- and L-glucose in 0.4 g of a Bio-Gel P-6 gel mixed for 18 hours in 4 ml of solutions containing 50 mM tetramethyl ammonium chloride, 10 mM D-glucose, 10 mM L-glucose, 3 mM sodium azide and graded concentrations of ethanol.
FIG. 13 illustrates the separation of D- and L-glucose in a Bio-Gel P-6 gel after 18 hours of mixing in a solution containing 25 mM tetramethyl ammonium chloride, 3 mM sodium azide, 20 mM D-glucose and 20 mM L-glucose, and graded concentrations of benzyl alcohol.
FIG. 14 shows the analysis of the experiment of FIG. 13 after 4 days of mixing.
FIG. 15 illustrates the separation of D- and L-glucose after 23 hours of mixing in solutions containing 25 mM tetramethylammonium chloride, 20 mM D-glucose, 20 mM L-glucose, 3 mM sodium azide, 10 mM n-butanol and graded concentrations of ethanol.
DETAILED DESCRIPTION OF THE INVENTION
It has been observed that small-pored polyamide gel beads and small-pored ion-exchange beads (both anion- and cation-selective) contain populations of high density and low density water molecules, known as microdomains, which have different solvent properties (Wiggins, P M (1990) Microbiol. Rev. 54:432-449; Wiggins, P M (1996) Cell Biol. Internat. 20:429-435; Wiggins, P M (1995) Progress in Polymer Science Prog. Polymer Sci. 20:1121-1163; Wiggins, P M (2001) Cell. Mol. Biol . (in press); Wiggins, P M (2001) In: Proceedings of Symposium on the Properties of Water p. 2000). Low density water preferentially dissolves K + , Rb + , Cs + , HCO 3 − , H 2 PO 4 − , NO 3 − , HSO 4 − , and tetramethyl ammonium ion. These ions are called chaotropes because they induce high density water; i.e. they displace the equilibrium between high and low density microdomains toward high density water, thus decreasing the structure of water and increasing its entropy, reactivity and fluidity. High density water preferentially dissolves Mg 2+ , Ca 2+ , H + , Li + , Na + , SO 4 2− , HPO 4 2− , F − and OH − . These ions are called kosmotropes because they induce low density water; i.e. they displace the equilibrium between high and low density water microdomains toward low density water, thus increasing the structure of water and decreasing its entropy and fluidity. Hydrocarbons are also kosmotropes. D-amino acids and L-glucose are kosmotropes, while L-amino acids and D-glucose are chaotropes.
In simple solutions, these solvent properties cannot be measured separately because the smallest sample of water contains both kinds of microdomain. At surfaces, however, the microdomains are no longer randomly distributed and a single type of microdomain can be probed for its solvent properties. A polyamide surface, for example, induces high density water immediately adjacent to its hydrophilic surface and low density water further out from the surface. When the pores of a polyamide gel are between 1-3 nm in diameter, their contained water is extremely enriched in low density water, which selectively accumulates chaotropes and excludes kosmotropes. The presence of microdomains of high and low density water within small-pored materials such as polyamide gels and ion exchange resins can thus be used to separate a chaotropic enantiomer from a kosmotropic enantiomer.
In order to use this property to separate similar solutes, the integrity of the microdomains must be protected by balancing kosmotropes in the external solution with chaotropes in the internal solution contained within the pores. Without this balance, a chaotrope accumulates into the low density water, creating an osmotic pressure gradient which is abolished by conversion of the low density water to high density water. The chaotrope then exits, and there is no retention of the solute on the gel.
Examples 2-5 (FIGS. 1-7) below describe experiments in which enantiomers were separated using columns of BioGel P-6 (Bio-Rad Laboratories, Richmond, Calif.) and of Dowex 50WX16 (Dow Chemical Company, Midland, Mich.). BioGel P-6 is a gel of polyacrylamide beads prepared by copolymerization of acrylamide and N,N′-methylene-bis-acrylamide. It is extremely hydrophilic and essentially non-ionic. Dowex 50WX16 is a cation exchange resin with approximately 16% cross-linkage. The columns were first preequilibrated for a stated time with an aqueous solution of a kosmotrope (usually butanol). A solution of DL-glucose, DL-lysine or DL-potassium glutamate was then put on the gel and eluted with the first eluting solution which was either water or the preparative solution of kosmotrope. The gel columns retained one enantiomer more than the other. The retained enantiomer was then eluted by converting the retaining water into the type with low affinity for the retained solute. Solutions considerably enriched one enantiomer or the other were thus obtained. These experiments were proof of principle that separated microdomains of water existed in the gels and could be used to separate D- and L-enantiomers. In the charged Dowex gels, both enantiomers were sometimes retained, but could be eluted separately by sequential elutions, the first of which converted low density water to high density water and the second of which converted high density water to low density water. Alternatively, the solute retained in low density water may be eluted under pressure.
The retention of the enantiomers was not due to chiral centres on the gel matrix because the gel beads were synthetic. The different populations of water molecules were believed to be a consequence of the coexistence of high and low density microdomains of pure liquid water (Mishima, O and Stanley, H E (1998) Nature 392:164-168; Mishima, O and Stanley, H E (1998) Nature 396:329-335; Vedamuthu, M. et al. (1994) J. Phys. Chem. 98:2222-2230; Robinson, G W and Cho, C H (1999) Biophys. J. 77:3311-3318). The difference in density of these two types of water (30%), with a corresponding difference in water—water bonding strengths, can account for the differences in solvent properties.
The amount of enantiomers that could be separated using the column procedure described in Examples 2-5 was relatively low. A batch procedure, in which larger amounts of enantiomers can be separated, was thus developed. Example 6 below describes experiments establishing the conditions for separation of D- and L-glucose on BioGel P-6 in a batch method. The preferred conditions for separation by the batch method are first determined by scanning solutions with concentrations of the racemic mixture of enantiomers, together with either a constant concentration of chaotrope and variable concentration of kosmotrope, or a constant concentration of kosmotrope and variable concentration of chaotrope. The preferred composition can be identified as the narrow range of compositions for which the gel volume is constant and maximal. Having identified the composition required to give maximal retention of D-glucose, the gel can be transferred to a column and eluted with a solution containing a solute which will selectively abolish the type of water retaining solute. In a polyamide gel, such as BioGel P-6, a chaotrope abolishes low density water. In a charged gel, such as Dowex, a kosmotrope abolishes low density water and a chaotrope abolishes high density water.
In order to optimize the batch method of separation of enantiomers, several variables must be tightly controlled. Since the enantiomers themselves are either chaotropes which partition into low density water and tend to induce high density water, or kosmotropes which partition into high density water and tend to induce low density water, there is no single protocol that will optimize separation of all racemic mixtures. For each racemic mixture, therefore, the type of scanning experiments described in Example 6 and illustrated in FIGS. 9-15, is initially necessary in order to determine the optima of time of mixing, concentration and identity of chaotrope, concentration and identity of kosmotrope, maximal useful concentration of racemate and volume of solution per gram of dry gel.
Stability of Gels
Polyamide gels in contact with water release NH 3 hydrolysed from end amide groups. This forms the powerful chaotrope NH 4 + , which interferes with separation unless the added chaotropes and kosmotropes are at high enough concentrations to predominate. Ion-exchange resins have highly reactive high density water immediately adjacent to their surfaces. This, with time, appears to cleave off fixed charge groups. Both polyamide gels and ion exchange resins, therefore, should be washed and dried between experiments and stored in the dry state.
Charged Gels
High capacity charged gels contain both high and low density water within their pores. Fixed charges (—SO 3 − , —CO 2 − , —N(CH 3 ) 3 + ) are usually chaotropic, inducing high density water immediately at the surface. Counter-ions can be chaotropic (K + , NH 4 +, or Cl − , HCO 3 − ) or kosmotropic (Na + , Li + , H + ). The most effective counter-ions for separation are divalent (Ca 2+ or Mg 2+ or SO 4 2+ ). These ions induce stable populations of high and low density water inside the pores, with high density water containing the counter-ions immediately adjacent to the surface and contiguous microdomains of low density water.
Charged gels should be converted to the divalent counter-ion form, washed with water to remove excess electrolyte and dried before use. If they are then mixed with a suitable concentration of racemate in a horizontal column, the enantiomers can be eluted sequentially with a solution of a kosmotrope followed by a solution of a chaotrope. All solutes are eluted when the gel is neutralized.
Time of Mixing
The experiments shown in FIGS. 13 and 14 illustrate the importance of the time of mixing of gel and solution. After 1 day of mixing, separation of D- and L-glucose was good, but after 4 days there was no separation. The internal volume of microporous gel beads is known to oscillate with time over a period of days. The periodicity of these oscillations depends upon the particular gel, the potency of chaotrope and kosmotrope, the temperature and the volume of water per gram of dry gel. For example, 25 mM tetramethylammonium chloride gave good separation after overnight mixing (FIG. 15 ), but 5 mM potassium phosphate required four days of mixing for good separation (FIG. 11 ).
Volume of Solution/g Gel
The collapse of internal low density water takes place when the osmolality of the internal solution becomes greater than that of the external solution. This occurs earlier when the volume of external solution is decreased. A suitable value for the volume of solution per gram of dry gel must be selected and not changed over the scanning experiments.
Chaotropes and Kosmotropes
Since the enantiomers to be separated will inevitably, themselves, have chaotropic or kosmotropic properties, the chaotropes and kosmotropes used to control the separation must be potent. Strong chaotropes are univalent salts of K + , Rb + , Cs + , NH 4 + and tetramethylammonium ion. The preferred anions are NO 3 − , HSO 4 − , and H 2 PO 4 − . The preferred chaotropic salt is KNO 3 because it is not complicated by an equilibrium for a doubly charged anion which is a kosmotrope.
When a chaotropic electrolyte is used, it is preferable to use a strong non-ionic kosmotrope, such as butanol or benzyl alcohol. These solvents have the added advantage that they can be eliminated from the final solutions by freeze-drying.
Water
The quality of water used in the scanning experiments and for washing the gel should be constant. The experiment illustrated in FIG. 8 used distilled, deionized water. When the experiment was repeated with MilliQ water, the minimum in pH shifted from 5 mM to 25 mM ethanol. Presumably the MilliQ water was of greater purity and retained fewer non-ionic kosmotropes which powerfully modify the properties of water even at trace concentrations. The studies shown in FIGS. 9 to 15 used MilliQ water. The absolute properties of water are not important, but they must be constant if the separations are to be reproducible.
Concentration of Racemate
The concentration of racemate must be high enough that useful levels of separation are obtained, but not high enough to control the separation of water domains entirely. When one enantiomer is a chaotrope and the other a kosmotrope, they will contribute to their separation by stabilizing low density water while it accumulates the chaotrope. In general, however, they should be at low enough concentrations that added solutes control the separation process.
Pressure and Temperature
Both increased pressure and temperature increase high density water at the expense of low density water. Temperature must be kept constant, therefore, for the scanning experiments. If the gel is poured into a column for the final separation of internal and external solutes, the column must be held horizontally and solutions pumped through with the minimum of pressure, so that low density water is not demolished prematurely. Alternatively, an increase in pressure may be employed to break down the regions of low density water with a resulting release of the chaotropic enantiomer. While the experiments described herein were all performed at room temperature, it is probable that higher temperatures would give greater separations in shorter times.
A scanning experiment to establish the optimal conditions for separation of a racemate may be performed using the following general procedures. Washed and dried BioGel P-6 is mixed with a solution containing 25 mM tetramethyl ammonium chloride, 10 mM butanol, 40 mM racemate, 3 mM sodium azide and graded concentrations of benzyl alcohol. Tubes are mixed for 20 hours, gel allowed to settle, and the height of the gel in the tube measured (as in FIG. 9 ). Mixing is continued and the gel heights measured at time intervals to determine the critical composition range for which the gel volume is a maximum as a function of time of mixing. Since no supernatant need be removed when only gel heights are estimated, the ratio of solution volume to gel weight is constant. With strong kosmotropes (such as butanol and benzyl alcohol) there appears to be a range of solution compositions giving some separation (see for example, FIGS. 13 and 15 ).
A definitive experiment can then be set up and analyzed in a polarimeter. Following the initial mixing, the gel slurry should be transferred to a rocking column for the predetermined time, and eluted, using a pump with slow flow rate, from the horizontal column, first with the mixing solution without the racemic mixture, and then with 50 mM KNO 3 .
The present invention is illustrated by reference to the following experimental protocols and results. The experimental protocols and results support the specification and claims and should not be construed to limit the invention, as claimed, in any fashion.
EXAMPLE 1
Effect of Varying Concentrations of External Kosmotrope on Gel Swelling
FIG. 8 illustrates the experimental design which was followed, with some modifications, in all experiments. In this experiment, 0.3 g of Bio-Gel P-6 gel was equilibrated over 6 days with solutions containing 5 mM potassium phosphate, pH 7, containing graded concentrations of ethanol. The end-point measured was the pH of the external solution. As the concentration of ethanol increased, a slight decrease in external pH was first observed which suddenly accelerated and assumed a minimal level (pH 5.3) at 5 mM ethanol. At 10 mM of ethanol, the pH had returned to 7. This is an example of the power of balancing external kosmotrope (ethanol, HPO 4 2− and H + ) with internal chaotrope (K + and H 2 PO 4 − ). The gel at first swelled with uptake of chaotrope and water, and stopped swelling when the osmotic pressure of the external solution exactly balanced that of the internal solution. This was the composition of solution which gave maximal retention of low density water inside the gel pores. Addition of further ethanol induced loss of internal water to balance the increased external osmotic pressure. With loss of internal water, the internal chaotrope concentrated and induced high density water inside the gel pores. Pore water then lost its selectivity for the chaotrope, which diffused out.
EXAMPLE 2
Separation of D-Glucose and L-Glucose on a Polyamide Gel Column
Unless otherwise indicated, in all experiments D-glucose was estimated using an Esprit Glucometer (BayerCorp., N.Y.). Standard solutions were diluted 1:1 with 4% polyethylene glycol 20M (BDH 298644E) to approximate the viscosity of blood for which the glucometer was designed. Corrections sometimes had to be made for changes in viscosity caused by varying chaotrope or kosmotrope in the sample solutions. The glucometer did not respond to L-glucose. L-glucose was labeled with 14 C and counted in a Wallac Microbeta Plus™ liquid scintillation counter. All solutions contained 3 mM sodium azide which ensured that microorganisms were absent but did not inhibit the glucose oxidase in the glucometer.
Two matched columns containing 1 g of BioGel P-6 were pretreated with two bed volumes of 0.2 M n-butanol for 24 h. Sequential experiments were carried out. In the first, 1 ml of 14 C-labeled D-glucose, 20 mM D-glucose, and 20 mM L-glucose in 0.2 M n-butanol was put on the column and eluted with 0.2 M n-butanol. In the second experiment, 1 ml of 14 C-labeled L-glucose, 20 mM L-glucose and 20 mM D-glucose was put on the column and eluted with 0.2 M butanol. Fractions were counted using a liquid scintillation counter.
As shown in FIG. 1, the elution patterns for L-glucose and D-glucose were different. Specifically, fractions 9-14 were enriched in L-glucose and fractions 14 to 29 were enriched in D-glucose. In these experiments, D-glucose, itself, was the chaotrope which induced high density water inside the gel, with resulting rapid loss of D-glucose and slight retention of L-glucose (fractions 29-40).
EXAMPLE 3
Separation of L-Lysine and D-Lysine on a Polyamide Gel Column
A column containing 1 g Bio-Gel P-6 gel was pretreated with 50 mM n-butanol for 21 hours. 1 ml of a solution containing 20 mM L-lysine, 20 mM D-lysine, 40 mM n-butanol and 14 C-L-lysine was put on the column and eluted with 15 ml 50 mM n-butanol followed by 20 ml of 20 mM NH 4 HCO 3 . Total lysine was determined from its absorbance relative to that of n-butanol at 210 nm, using a standard curve of lysine in 50 mM n-butanol. L-lysine concentration was determined by scintillation counting. Following addition of NH 4 HCO 3 , total lysine could not be measured. As shown in FIG. 2, L-lysine was retained on the column in low density water, which was then demolished by the potent chaotrope, NH 4 HCO 3 , with resulting release of L-lysine. D-lysine concentration was obtained by difference.
The properties of Bio-Gel P-6 were found to vary from batch to batch. In this experiment, using a different batch of Bio-Gel P-6, 10 mM of each of D- and L-lysine, and 50 mM KH 2 PO 4 as the second elution solution, the elution patterns were different to those described above. By making corrections for (i) the effects of changing solution composition on the absorbance of lysine at 210 nm, and (ii) NH 3 produced from the gel and eluted with lysine, total lysine was measured up to 30 ml. As shown in FIG. 3, both D- and L-lysine were totally recovered.
EXAMPLE 4
Separation of L-Glutamate and D-Glutamate on an Ion Exchange Resin Column
Dowex 50Wx16 (Dow Chemical Company, Midland, Mich.) in its sodium form was pre-equilibrated in water for 12 days. 1 ml of 20 mM potassium D-glutamate, 20 mM potassium L-glutamate and 14 C L-glutamate was put on the column and eluted with 19 ml of water, followed by 15 ml of 0.1 M MgCl 2 . L-Glutamate was determined by scintillation counting of 14 C and total glutamate by absorbance at 210 nm. Corrections had to be made for a solute, eluted from the gel, which absorbed at 210 nm but which was not glutamate. FIG. 4 shows the elution pattern of L- and DL-glutamate, with FIG. 5 showing the elution of D-glutamate, obtained by difference. Most L-glutamate eluted with water, with the rest being subsequently eluted with the kosmotrope MgCl 2 . D-Glutamate was retained on the gel, presumably in high density water. MgCl 2 partitioned into high density water, increasing its volume at the expense of low density water so that L-glutamate was concentrated in low density water, thereby inducing high density water, and was eluted. Any residual D-glutamate would be eluted by a solution of a chaotrope. Dowex 50Wx16 is a strongly negatively charged gel which, here, has retained the anion D-glutamate. The time of pre-treatment of gels with water or kosmotropic solution is critical to the result. The necessity of a long pre-treatment period is due to the need for the gel surface to modify itself with time to maximise the formation of high and low density microdomains. The Dowex cross-linked gel matrix is in a glassy or rubbery state and therefore very slow to move.
In subsequent experiments, Dowex 50Wx16 was converted to its K + form and well-washed with 0.2 M butanol to remove excess ions. After 8 days, 0.5 ml of 20 mM potassium D-glutamate, 20 mM L-glutamate and 14 C-L-glutamate in 0.2 M butanol was put on the column and eluted with 8 ml 0.2 M butanol followed by 0.1 M KH 2 PO 4 . Previous experiments have shown that the properties of water in a charged gel are exquisitely sensitive to the counter-ion. With K + as the counter-ion, more low density water is induced than when Na + is the counter-ion. Accordingly, in this experiment, half of the D-glutamate was eluted with butanol and the rest with the chaotrope KH 2 PO 4 which, at a charged surface, induces low density water, eluting the kosmotropic D-glutamate. L-glutamate was most strongly retained on the column, with only 40% being eluted. These results are shown in FIG. 6 .
EXAMPLE 5
Separation of Chloroquine Phosphate on a Polyamide Gel Column
Chloroquine phosphate (ICI Pharmaceuticals Division, Bridgewater, N.J.) is a racemic mixture of a drug. 1 ml of 20 mM DL-chloroquine phosphate was put on a Bio-Gel P-6 column pretreated with water for 21 hours, and eluted with 14 ml of water followed by 50 ml of 50 mM NH 4 NO 3 . Total chloroquine in the fractions was estimated by absorbance at 240 nm. As shown in FIG. 7, while no drug was eluted with water, all the drug eluted following abolition of internal low density water by addition of the chaotrope 50 mM NH 4 NO 3 . The solute appears to have eluted in two fractions as evidenced by the shoulder on the peak.
EXAMPLE 6
Optimization of Conditions for Separation of D-Glucose and L-Glucose using a Batch Method
1 g of washed and dried Bio-Gel P-6 was weighed into each of a series of 15 ml calibrated centrifuge tubes and 7.5 ml of solution added. Solutions contained 10 mM D-glucose, 10 mM L-glucose, 5 mM tetramethyl ammonium chloride, 3 mM sodium azide, 14 C-L-glucose and concentrations of ethanol ranging from 0-40 mM. Tubes were mixed on a rotating mixer at 21° C. for 20 hours, the gel allowed to settle and supernatants analyzed for D- and L-glucose. In these experiments, tetramethyl ammonium chloride was the constant chaotrope and ethanol the variable kosmotrope. The results are shown in FIG. 9 . The volume of gel in the calibrated tube was estimated by eye and was found to be fairly constant from 0 to 24 mM ethanol and then rather abruptly increased and levelled out. At this largely constant degree of swelling, the supernatant, or external solution, increased to a maximum concentration of L-glucose and decreased in D-glucose concentration. The tube with the greatest separation of D- and L-glucose had a ratio of D:L of 0.75:1.
In further experiments, 1 g of Bio-Gel P-6 was weighed into each of a series of 15 ml calibrated centrifuge tubes and put on the mixer in 8 ml solution and mixed for 46 hours. Solutions contained 10 mM D-glucose, 10 mM L-glucose, 14 C-L-glucose, 3 mM sodium azide, 20 mM ethanol and concentrations of tetramethyl ammonium chloride ranging from 25 to 100 mM. This is the reciprocal of the experiment shown in FIG. 9 . The kosmotrope (ethanol) was at a constant concentration and the chaotrope (tetramethylammonium chloride) varied from 25 to 100 mM. As shown in FIG. 10, there was a clear maximum in L-glucose concentration, minimum in D-glucose concentration and maximum in gel volume at approximately 60 mM tetramethyl ammonium chloride. The ratio of D- to L-glucose at this point was 0.72:1.
In subsequent experiments, 0.5 g BioGel P-4 was weighed into each of a series of tubes and mixed at 21° C. with 4 ml solution over 4 days. Solutions contained 20 mM L-glucose, 20 mM D-glucose, 14 C-L-glucose, 5 mM potassium phosphate pH 7, 2 mM benzyl alcohol, 3 mM sodium azide and graded concentrations of ethanol from 0-50 mM. The results are shown in FIG. 11 . Separation was continuing at 50 mM ethanol, at which point the ratio of D- to L-glucose was 1:0.79.
FIG. 12 shows the results of experiments in which 0.4 g washed Bio-Gel P-6 was weighed into each of a series of tubes and mixed with 4 ml solution for 21 hours. Solutions contained 50 mM tetramethyl ammonium choride, 10 mM D-glucose, 10 mM L-glucose, 14 C-L-glucose, 3 mM sodium azide and graded concentrations of ethanol from 0 to 100 mM.
In further experiments, 0.5 g of washed Bio-Gel P-6 was weighed into each of a series of tubes and mixed for 21 hours at room temperature in 4 ml solution. Solutions contained 25 mM tetramethyl ammonium chloride, 20 mM D-glucose, 20 mM L-glucose 14 C-L-glucose, 3 mM sodium azide, 10 mM butanol and variable concentrations of benzyl alcohol from 0 to 20 mM. These solutions contained both a strong chaotrope (tetramethyl ammonium chloride) and strong kosmotropes (butanol and benzyl alcohol). FIG. 13 shows the result after 21 hours of mixing. The average ratio of D- to L-glucose was 0.69:1 and this was maintained over a quite wide range of concentrations of benzyl alcohol, because the solutions also had the constant concentration of n-butanol (10 mM). The combination of strong chaotrope and strong kosmotrope allowed good separation of the enantiomers.
FIG. 14, however, shows the results after 4 days of mixing. These were the same samples as those shown in FIG. 13, put back on the mixer after removal of 120 μl of supernatant for analysis. After 4 days of mixing there was no separation of the enantiomers at all. It has been shown in other experiments that the internal volume of microporous gel beads oscillates with time over a period of days (Wiggins, P M, (1995): Microosmosis, a chaotic phenomenon of water and solutes in gels. Langmuir 11: 1984-1986). The maximal internal volume coincides with maximal separation of low density and high density microdomains. In this example, therefore, it seems probable that separation of microdomains was high after 21 hours of mixing, but zero after 4 days of mixing. The slowness of these volume changes is due to the slow movement of the cross-linked gel matrix which has to adapt to the influx or efflux of water in response to uptake and release of chaotropes.
In yet further experiments, 0.4 g fresh Bio-Gel P-6 was weighed into each of a series of tubes and mixed in 4 ml of solution for 23 hours at 21° C. Solutions contained 25 mM tetramethyl ammonium chloride, 20 mM D-glucose, 20 mM L-glucose, 10 mM BuOH, 14 C-L-glucose, 3 mM sodium azide and graded concentrations of ethanol from 0 to 100 mM. FIG. 15 shows the results. Again, in the presence of a strong kosmotrope (butanol) there was a degree of separation at all concentrations of ethanol. However, there was a point of maximal separation at 20 mM ethanol for which the ratio of D- to L-glucose in the external solution was 1:0.64. This sample of Bio-Gel P-6 was used as obtained from the makers (BioRad Laboratories) without washing so that it contained some preservative, presumably ethanol or other kosmotrope, which adds an unknown kosmotropic influence on the separation. All other experiments used gel washed in water and dried at 110 ° C.
These experiments demonstrate that the batch method may be employed to enrich the internal solution with D-glucose and enrich the external solution with L-glucose.
All references and other materials cited herein are incorporated by reference in their entirety. While in the foregoing specification this invention has been described in relation to certain preferred embodiments thereof, and many details have been set forth for purposes of illustration, it will be apparent to those skilled in the art that the invention is susceptible to additional embodiments and that certain of the details described herein may be varied considerably without departing from the basic principles of the invention. | Methods for the separation of chaotropic and kosmotropic enantiomers within a racemic mixture are provided. Such methods comprise differentially partitioning the enantiomers into stabilized microdomains of low density water and high density water abutting a porous surface. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is the U.S. national phase of PCT Appln. No. PCT/EP2007/051664 filed Feb. 21, 2007 which claims priority to German application DE 10 2006 009 954.0 filed Mar. 3, 2006.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method of reutilizing high-boiling compounds within an integrated chlorosilane plant.
2. Description of the Related Art
In the various subprocesses of the production of polycrystalline silicon, various chlorosilane compounds including high-boiling dichlorosilanes and oligochlorosilanes (HBs) are formed. The expression “high-boiling compound, high-boiling dichlorosilane and oligochlorosilane” or “high boiler” refers here to a compound which consists of silicon, chlorine, and possibly hydrogen, oxygen and carbon, and has a boiling point higher than that of tetrachlorosilane (57° C./at 1013 hPa). The compounds are preferably disilanes H n Cl 6-n Si 2 (n=0−4) and higher oligo(chloro)silanes which preferably have from 2 to 4 Si atoms and also disiloxanes H n Cl 6-n Si 2 O (n=0−4) and higher siloxanes which preferably have from 2 to 4 Si atoms, including cyclic oligosiloxanes and their methyl derivatives. In the following, low-boiling silanes having a boiling point of <40° C. under atmospheric conditions (1013 hPa) will be referred to as LBs for short.
Both the synthesis of trichlorosilane (TCS) from metallurgical silicon and HCl and the deposition of polycrystalline silicon (Poly) from trichlorosilane are based on thermal equilibrium processes of chlorosilanes, as are described, for example, in E. Sirtl, K. Reuschel, Z. ANORG. ALLG CHEM. 332, 113 216, 1964, or L. P. Hunt, E. Sirtl, J. ELECTROCHEM. SOC. 119(12), 1741-1745,1972. Accordingly, the trichlorosilane synthesis forms not only trichlorosilane and silicon tetrachloride (STC) but also dichlorosilanes and monochlorosilanes and also HBs according to a thermal equilibrium. The crude trichlorosilane from the trichlorosilane synthesis contains 0.05-5% of these HBs. In addition, about 20 ppm of various boron compounds, up to 200 ppm of TiCl4 and other metal chlorides such as FeCl2, FeCl3 and AlCl3 are formed in crude trichlorosilane production. These have to be separated from the products trichlorosilane and silicon tetrachloride.
Methods of separating trichlorosilane and silicon tetrachloride from the abovementioned HBs are known. Thus, U.S. Pat. No. 5,252,307, U.S. Pat. No. 5,080,804, U.S. Pat. No. 4,690,810 or U.S. Pat. No. 4,252,780 describe the concentration of the HB fractions contaminated with metal chlorides to 1% by weight to 50% by weight in the bottom offtake stream, followed by subsequent hydrolysis and disposal as hydrolysis residue. These processes result in silicon and chlorine losses and also in problems in disposing of the hydrolysate and the HCl-containing wastewater obtained [M. G. Kroupa in Proceedings. from SILICON FOR THE CHEMICAL INDUSTRY VI, pp. 201-207, Loen, Norway, Jun. 17-21, 2002].
Further undesirable high-boiling chlorodisiloxane fractions arise in the distillation and partial hydrolytic purification of chlorosilanes. These high-boiling fractions have hitherto likewise been disposed of as hydrolysis residues and HCl-containing wastewater, as described, for example, in U.S. Pat. No. 6,344,578 B1, U.S. Pat. No. 3,540,861 or U.S. Pat. No. 4,374,110.
Furthermore, it has been both theoretically deduced [E. Sirtl, K. Reuschel, Z. ANORG. ALLG CHEM. 332, 113 216, 1964; E. Sirtl et al., J. ELECTROCHEM. SOC. 121, 919-,1974; V. F. Kochubei et al., KINET. KATAL., 19(4), 1084, 1978] and demonstrated analytically [V. S. Ban et al., J. ELECTROCHEM. SOC. 122, 1382-, 1975] that HBs (hexachlorodisilane, pentachlorodisilane, tetrachlorodisilane and trichlorodisilane) are also formed in the deposition of polycrystalline silicon from trichlorosilane. These HBs, which are highly pure in respect of dopants and metals, are present in the bottom offtake stream from the polycondensate distillation, which can be converted by means of silicon tetrachloride at 600-1200° C. [WO02/100776 A1].
HBs can also be cracked in the presence of hydrogen in a low-temperature conversion in a fluidized-bed reactor [JPHei1-188414-Osaka Titanium 1988].
Polychlorosilanes (Si n Cl 2n+2 ; 4≧n≧2), in particular Si 2 Cl 6 (HCDS) decompose at z 700° C. in the presence of silicon crystal nuclei or on a heated silicon core [EP282037-Mitsubishi 1988]. It is also known that highly pure HCDS can be isolated from the offgases from the deposition of polycrystalline silicon [WO2002012122-Mitsubishi, 2002]. The cleavage of polychlorodisilanes by means of HCl over activated carbon can proceed even in the range from 30 to 150° C. [JP09-263405-Tokuyama 1996]. The reaction of this HB fraction together with silicon tetrachloride and hydrogen can be carried out in a high-temperature reactor (Dow Corning 2001 [US2002/0187096]). Disilanes from the direct synthesis of organosilanes can likewise be converted into trichlorosilane and/or silicon tetrachloride at 300° C. [U.S. Pat. No. 6,344,578 B1 Wacker 2000]. Low-temperature cleavage occurs in the presence of nucleophilic catalysts [F. Hoefler et al., Z. ANORG. ALLG. CHEM. 428, 75-82, 1977; DE3503262-Wacker 1985; G. Laroze et al, Proceedings, from SILICON FOR THE CHEMICAL INDUSTRY III, pp. 297-307, Trondheim, Norway, 1996; W.-W. du Mont et al, ORGANOSILICON CHEMISTRY V, Sep. 2001, Chem. Abst., 142:1555991; G. Roewer et al., SILICON CARBIDE—A SURVEY IN STRUCTURE AND BONDING 101, pp. 69-71, Springer 2002]. Lewis acids such as AlCl 3 can likewise catalyze the cleavage of Si—Si bonds [A. Gupper et al., EUR. J. INORG. CHEM, 8, 2007-2011, 2001].
All these methods of removing undesirable HBs from processes for producing polycrystalline silicon involve a high engineering outlay for the disposal, separation and purification steps. In addition, losses of chlorine and silicon cannot be avoided.
The thermal decomposition of HBs in the presence of silicon tetrachloride and hydrogen is known from JPHei1-188414 of Osaka Titanium.
SUMMARY OF THE INVENTION
The present invention provides a process for preparing trichlorosilane by reaction of metallurgical silicon and HCl at a temperature of from 290° C. to 400° C. in a fluidized-bed reactor, which is characterized in that a high-boiling compound is fed into the fluidized-bed reactor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates one embodiment of the process of the invention in schematic form.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The HBs preferably originate from the offgases formed in the production of polycrystalline silicon or in the preparation of trichlorosilane. The process of the invention thus makes it possible to increase the trichlorosilane yield in the preparation in a fluidized-bed reactor and allows inexpensive reutilization of HBs. It minimizes the silicon losses and decreases pollution of the environment by reducing the need for deposition in landfill and reducing the amount of acidic hydrolysate products.
FIG. 1 shows, by way of example, an integrated chlorosilane plant comprising an embodiment of the recirculation ( 4 / 10 ) according to the invention of the HBs from the offgases formed in the preparation of trichlorosilane in a fluidized-bed reactor ( 3 ) or in the production of polycrystalline silicon (deposition 2 ).
The offgases ( 7 ) from the fluidized-bed reactor ( 3 ) are introduced via a dust removal system, generally a dust filter ( 13 ), and a condensation system ( 14 ) into a separation column ( 1 a and 1 b ) where trichlorosilane and LBs are separated from silicon tetrachloride and HBs. Silicon tetrachloride and HBs are introduced into a high boiler column ( 1 c ) where silicon tetrachloride is partly separated from the HBs. In an embodiment of the process of the invention, the HB-containing mixture having an atmospheric boiling point of 80-155° C. is recirculated ( 4 ) into a fluidized-bed reactor ( 3 ) for producing trichlorosilane within the integrated chlorosilane plant.
In another embodiment of the process of the invention, the offgas originating from the deposition ( 2 ) for the production of polycrystalline silicon is recirculated to a fluidized-bed reactor ( 3 ) for producing trichlorosilane within the integrated chlorosilane plant. The offgas from the deposition is preferably conveyed via a condensation system ( 15 ) to a polycondensate column ( 8 ) in which silicon tetrachloride and HBs are separated from trichlorosilane and LBs. Silicon tetrachloride and HBs are in turn introduced into an HB enrichment column ( 9 ) in which silicon tetrachloride is partly separated off from HBs. The HBs mixture formed here is, according to the invention, recirculated ( 10 ) to the fluidized-bed reactor ( 3 ) for producing trichlorosilane. It is likewise possible to recirculate an offgas mixture from both embodiments of the process of the invention to the fluidized-bed reactor for producing trichlorosilane. It has surprisingly been found that the HB-containing mixtures react with metallic silicon to form trichlorosilane in a fluidized-bed reactor ( 3 ).
In the first process variant mentioned, the HB fraction ( 4 ) is preferably recirculated from the lower side offtake of the HB distillation ( 1 c ) to a fluidized-bed trichlorosilane reactor ( 3 ). Preference is given to feeding part (1-50%) of the HB fraction from the lower side offtake of the HB distillation ( 1 c ) to the HB destruction ( 5 ) in order to avoid an increase in the concentration of silicon tetrachloride and TiCl 4 and AlCl 3 and other metal chlorides and also siloxane in the fluidized-bed reactor 3 . Preference is given here to recirculating 50-99% by weight of the HB fraction having an atmospheric boiling point of 80-155° C. from the lower side offtake of the high boiler distillation ( 1 c ) to a fluidized-bed trichlorosilane reactor ( 3 ). The recirculated HB mixture also contains silicon tetrachloride (<50%) and abovementioned metal chlorides in a concentration of <5000 ppm. This variant of the process of the invention reduces the disposal to HB destruction by 50-99% by weight so as to protect the environment and increases crude trichlorosilane production by up to 1% by weight.
The offgas ( 16 ) of a deposition reactor ( 2 ) for the production of polycrystalline silicon from trichlorosilane also comprises HBs together with monochlorosilane, monosilane, dichlorosilane, trichlorosilane and silicon tetrachloride. After trichlorosilane and silicon tetrachloride have been partly separated off by distillation in the polycondensate column ( 8 ), the HBs are concentrated to 0.5-20% by weight in the residue. These HBs are obtained as bottom product from the polycondensate column ( 8 ) in a fraction at atmospheric pressure and a temperature of 80-155° C. If appropriate, the HB mixture can be concentrated to 50% of HBs in an enrichment column ( 9 ).
It has been found that this HB-containing fraction ( 10 ) can be cleaved without problems to give trichlorosilane and silicon tetrachloride in the fluidized-bed trichlorosilane reactor ( 3 ). Since this HB fraction comprises both HBs and silicon tetrachloride but is obtained in a very high purity in respect of dopants, carbon compounds and metal compounds, this fraction can be recirculated directly to the fluidized-bed reactor ( 3 ). After recirculation ( 10 ) into the fluidized-bed reactor ( 3 ), no accumulation of HBs in the offgas ( 7 ) from the fluidized-bed oven ( 3 ) was found. This variant of the process of the invention makes it possible to achieve 100% reutilization of the HBs from the offgas ( 16 ) from the deposition of polycrystalline silicon, so that environmentally polluting disposal is no longer necessary. In addition, the yield in the production of crude trichlorosilane is increased by at least 2% by weight.
In the process, silicon tetrachloride is obtained as a highly pure overhead product from the HB enrichment column ( 9 ) and the HB column ( 1 c ). This silicon tetrachloride can either be converted into trichlorosilane by means of hydrogen (DE 3024319) in a converter ( 17 ) or pyrolyzed in a flame to form finely divided silica (HDK®, 17 ) (DE4322804), as described by T. Lovreyer and K. Hesse (T. Lobreyer et al. im Proceedings, from, SILICON FOR THE CHEMICAL INDUSTRY IV, in Geiranger, Norway, Jun. 3-5, 1998, pp. 93-100 Ed.: H. A. Oye, H. M. Rong, L. Nygaard, G. Schussler, J. Kr. Tuset).
The recirculation of the HB mixture ( 4 / 10 ) or the separated high boiler fractions ( 4 and 10 ) to the fluidized-bed reactor ( 3 ) is preferably effected via a saturator ( 6 ).
In the saturator ( 6 ), the HB mixture is mixed into part of the HCl (preferably from 10 to 40% by weight) ( 11 ) and mixed with the main stream of HCl and added metallic silicon ( 12 , MGSi) which is fed to the fluidized-bed reactor for producing trichlorosilane. This mixture is fed to the fluidized-bed reactor ( 3 ).
Analysis of the composition of the HB mixture ( 4 ) and the offgas composition ( 7 ) after a number of days of operation has indicated that the concentration of polychlorodisiloxanes H n Cl 6-n Si 2 O (n=0−4) has increased by about one order of magnitude, which does not adversely affect the process. An increase in the concentration of metal chlorides which would interfere in the process was not measurable in the process of the invention.
The following examples serve to illustrate the invention:
Example 1
Preparation of Trichlorosilane
Comparative Example
In a reactor system comprising a fluidized-bed reactor ( 3 ), a dust removal system ( 13 ) and a condensation system ( 14 ) (described in U.S. Pat. No. 4,130,632), metallurgical silicon having a purity of >98% of silicon was reacted with hydrogen chloride gas.
This gave, after condensation, a crude silane mixture comprising 70-90% by weight of trichlorosilane, 10-29.2% by weight of silicon tetrachloride, 0.1-0.5% of LBs (dichlorosilane and monochlorosilane) and 0.1-0.3% of HBs. Furthermore, the crude silane contained metal chlorides (e.g. TiCl 4 and AlCl 3 ) in the ppm range.
About 2 t/h of crude silane were produced from 425 kg/h of silicon and 1750 kg/h of HCl. The composition of the crude silane was 0.35% of low boilers (monochlorosilane and dichlorosilane), 79.3% of trichlorosilane, 20.1% of silicon tetrachloride and 0.25% of HBs. The HB fraction was composed of about 50% of disilanes, 47% of disiloxanes and about 3% of higher polychlorooligosilanes and siloxanes. About 5 kg/h of HB fraction were formed. This amount corresponds to about 2.5 kg of HB fraction per 1000 kg of crude silane produced, which therefore had to be disposed of by hydrolysis.
Example 2
Return ( 4 ) of the HBs from the offgas ( 7 ) from the preparation of trichlorosilane as described in example 1 to the preparation of trichlorosilane in the fluidized-bed reactor ( 3 ).
A process for preparing crude silanes was carried out as described in example 1. The offgases from the process were fed to the separation column ( 1 a ) and then introduced into a high boiler column ( 1 c ). The HBs were enriched in this way. About 20% by weight (1 kg/h) of the HB fraction were separated off and passed to HB destruction ( 5 ). The remaining 4 kg/h of the HB fraction were transferred to a heatable saturator ( 6 ) and from there fed with the aid of an HCl carrier gas stream ( 11 ) to the fluidized-bed reactor ( 3 ). The total amount of HCl ( 11 + 12 ) was divided for this purpose (90% was fed directly ( 12 ) into the fluidized bed ( 3 ) and 10% of the amount of HCl was used as carrier gas ( 11 ) for conveying HBs). At the prescribed reaction temperature, the cleavable components of the HB fraction were converted into monomers, while uncleavable components accumulate to some extent in the crude silane.
In this example, only 1.2 kg of HB fraction per 1000 kg of crude silane had to be disposed of by hydrolysis.
Example 3
Return ( 10 ) of the HBs from the offgas ( 16 ) from the production of polycrystalline silicon ( 2 ) to the preparation of trichlorosilane in the fluidized-bed reactor ( 3 ).
The process for preparing crude silane was carried out as described in example 1. In addition, 10 kg/h of the HB fraction from the polydeposition ( 2 ) together with 1/10 of the total amount of HCl ( 11 ) were fed via the saturator ( 6 ) into the fluidized-bed reactor ( 3 ).
It was surprisingly found that the composition of the crude silane obtained in this way did not differ from that from example 1 (0.25% of HBs). This means that the polychlorodisilanes in the HB fraction were converted completely into monomers such as trichlorosilane or silicon tetrachloride.
No additional HBs which had to be disposed of were formed. The HBs obtained in the polydeposition ( 2 ) could, after condensation ( 15 ) and separation by distillation ( 8 ) or enrichment ( 9 ), be converted completely into trichlorosilane or silicon tetrachloride by recirculation ( 10 ) to the fluidized-bed reactor ( 3 ) in the process of the invention.
Example 4
Return of the HBs from an Offgas Mixture 4 and 10
It has in practice been found to be useful to process the HB fractions together. The synthesis was carried out as described in example 1. In addition, 4 kg/h of HB fraction from the high boiler column ( 1 c ) and 10 kg/h of HBs from the offgas ( 16 ) from the polydeposition ( 2 ) were introduced into the saturator ( 6 ) and then fed together with about 175 kg/h of HCl carrier gas ( 11 ) into the fluidized-bed reactor ( 3 ). As in example 2, the concentration of oligosiloxanes in the crude silane increased somewhat.
1.2 kg of HBs per 1000 kg of crude silane had to be disposed of by means of hydrolysis in the HB destruction ( 5 ). | Trichlorosilane production is increased while simultaneously lowering environmental burden due to destruction and disposition of high boilers by feeding high boilers from trichlorosilane production or from polycrystalline silicon production into a fluidized bed for production of trichlorosilane from metallic silicon and hydrogen chloride. | 2 |
[0001] This application is a Divisional of Ser. No. 09/845,362, filed Apr. 30, 2001.
FIELD OF THE INVENTION
[0002] The present invention applies to on-line Internet shopping, and more particularly to a method for managing and updating a shopping cart conveniently as an on-line customer adds, changes, and deletes items from the shopping cart.
BACKGROUND
[0003] On-line commerce is now an important part of our economy, mainly because of the efficiency and the ready convenience that on-line commerce provides. As a general principle, ready convenience and good human factors go hand-in-hand. Moreover, each improvement in human factors opens the use of electronic commerce to a larger segment of the population.
[0004] Today, however, many would-be participants in electronic commerce (e-commerce) are limited by the capabilities of the computer systems they use to gain access to e-commerce web servers. This limitation is often experienced, for example, by customers who shop on-line. Because the items to be purchased are not actually seen by the customer at the time the items are selected—rather, the items are carried virtually in an abstract shopping cart—the customer is not able to keep track of purchases conveniently.
[0005] One way that the lack of visibility may confound a shopper involves the purchase of linked items. Items are linked when the purchase of a primary item, for example a computer printer, is normally coupled with the purchase of a secondary item, for example a power cord for the printer. When the shopper changes the quantity of a primary item in the shopping cart, for example revising the quantity of the order from four printers to six printers, the shopper must remember also to revise the quantity of the secondary item, here from four power cords to six.
[0006] If the shopper forgets to change an attribute of the secondary items in the shopping cart in response to each change in a related attribute of the primary items, the shopper's order will not be filled as intended. As a result, the shopper will be disappointed by the on-line shopping experience, and perhaps be disappointed in the on-line merchant as well.
[0007] Thus there is a need for a way of helping an on-line shopper maintain the proper relationship in the shopping cart between primary items and secondary items that are normally ordered along with the primary items, so that the on-line merchant may fill the shopper's order as the shopper intends, and so that the shopper maintains confidence in the on-line shopping process.
SUMMARY OF THE INVENTION
[0008] The present invention helps an on-line shopper maintain the proper relationship between primary items in a shopping cart and secondary items in the shopping cart, where secondary items are items that normally accompany the purchase of primary items. According to the invention, the server that provides the on-line shopping service awaits a shopper's commands. When a command is received that changes an attribute of a primary item, the server checks the shopper's shopping cart to identify any secondary items that might be linked to the primary item being changed. If a secondary item linked to the primary item is identified, the server may then solicit the shopper's authorization to change the corresponding attribute of the secondary item. If the shopper grants authorization, either explicitly or implicitly, the server changes the corresponding attribute of the secondary item.
[0009] In one embodiment of the invention, the attribute of the primary item is the quantity of the primary item in the shopping cart. When the shopper changes the quantity of the primary item in the shopping cart, the server correspondingly changes the quantity of the secondary item. For example, when the shopper changes the contents of the shopping cart from four printers to six printers, the server changes the quantity of power cords in the shopping cart from four to six. Optionally, the server asks the shopper for authorization to make the change. The shopper may grant authorization explicitly in response to the server's request, or implicitly by entering a “submit” command that may be responsive to either the change in the quantity of the primary item or the proposed change in the quantity of the secondary item.
[0010] In another embodiment of the invention, the attribute of the primary item in the shopping cart is the size of the primary item. Upon change of the size and optionally upon grant of authorization by the shopper, the server changes the size of the secondary item to agree with the size of the primary item. For example, when the shopper changes the size of a photograph in the shopping cart from five-by-seven inches to eight-by-ten inches, the server asks if it may change the size of a mounting board or picture frame in the shopping cart accordingly. If the shopper authorizes the change, the server reconfigures the shopping cart to include a mounting board or picture frame of the proper size.
[0011] In yet another embodiment of the invention, the attribute of the primary item in the shopping cart is the color of the primary item. Upon change of the color and optionally upon grant of authorization by the shopper, the server changes the color of the secondary item to agree with the color of the primary item. For example, when the shopper changes the color of a bath towel in the shopping cart from blue to green, the server asks if it may change the color of a washcloth linked to the bath towel in the shopping cart from blue to green. If the shopper authorizes the change, the server reconfigures the shopping cart to include a green washcloth rather than a blue washcloth.
[0012] In another embodiment of the invention, the attribute of the primary item in the shopping cart is the presence or absence of the primary item. Upon removal of the primary item from the shopping cart and optionally upon grant of authorization by the shopper, the server removes the secondary item from the shopping cart. For example, when the shopper removes a green bath towel from the shopping cart, the server asks if it may remove a green washcloth associated with the towel in the shopping cart. If the shopper authorizes the removal, the server removes the green washcloth from the shopping cart.
[0013] Thus, the present invention helps an on-line shopper to maintain the proper relationship in a shopping cart between primary items and secondary items that are normally ordered along with the primary items, so that the on-line merchant may fill the shopper's order as the shopper intends, and so that the shopper maintains confidence in the on-line shopping process. These and other aspects of the present invention will be more fully appreciated when considered in light of the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 . shows an on-line shopper connected to an on-line merchant's server through the Internet.
[0015] FIG. 2 shows an exemplary shopping cart of items gathered by the on-line shopper of FIG. 1 .
[0016] FIG. 3 shows aspects of the operation of the server of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
[0017] The present invention helps an on-line shopper to maintain the proper relationship in a shopping cart between primary items and secondary items that are normally ordered along with the primary items, so that the on-line merchant may fill the shopper's order as the shopper intends, and so that the shopper maintains confidence in the on-line shopping process.
[0018] FIG. 1 shows an environment suitable for application of the present invention. In FIG. 1 , an on-line shopper 100 interacts with a client 110 to access an on-line merchant 130 through the Internet 120 or other communication network. The client 110 may be a computer terminal, a personal digital assistant, a cellular telephone with a wireless access protocol (WAP) browser, and so forth.
[0019] The shopper 100 uses shopping commands to assemble a shopping cart 200 of items to be purchased from the merchant 130 , as shown in FIG. 2 , adding items to the shopping cart 200 , changing items in the shopping cart 200 , and removing items from the shopping cart 200 . Items in the shopping cart 200 are categorized here as primary items, two of which 210 and 230 are shown in the exemplary shopping cart 200 , secondary items, N+M of which are shown 220 A through 220 N and 240 A through 240 M in the shopping cart 200 , and stand-alone items, two of which 250 and 260 are shown in the shopping cart 200 .
[0020] The secondary items 220 A through 220 N and 240 A through 240 M are linked to the primary items 210 and 230 , where a link is established as explained below. A secondary item is an item whose purchase is often dependent upon the purchase of the linked primary item. For example, when the primary item “shoes” is purchased, the secondary items “socks” or “shoe polish” may often be purchased at the same time. Typically, the server 140 will direct the attention of the shopper 100 to a secondary item upon selection of a primary item by the shopper 100 . The on-line merchant 130 decides which items are primary, which are secondary, and which are linked to which. The stand-alone items 250 and 260 shown in the shopping cart 200 are items which the merchant 130 has not deemed to be either primary or secondary items, or are secondary items that have no antecedent primary items in the shopping cart 200 .
[0021] The shopper 100 uses shopping commands to direct the server 140 . These commands may include, for example, “add item to shopping cart,” or “change item in shopping cart,” and “remove item from shopping cart,” where the particular item and command may be selected by a computer mouse acting upon a web page presented to the shopper 100 by the client 110 . The web page upon which the mouse acts may be, for example, a shopping cart page, a product page that describes an item that may be added to a shopping cart, and so forth, including herein any kind of on-line shopping display such as a web page.
[0022] In response to the shopping commands, the server 140 helps the shopper 100 manage the contents of the shopping cart 200 , as shown in FIG. 3 . The server 140 awaits a shopping command (step 300 ). When a shopping command is not received, the server continues to wait (step 300 ). Otherwise (i.e., a shopping command is received), the server 140 determines whether the shopping command alters an attribute of one of the primary items 210 and 230 in the shopping cart 200 (step 305 ). When no attribute of the primary items 210 and 230 is altered, the server 140 awaits the arrival of the next shopping command (step 300 ).
[0023] Otherwise (i.e., the shopping command alters an attribute of a primary item in the shopping cart 200 ), the server 140 determines if the shopper 100 is adding a new (i.e., heretofore absent) primary item to the shopping cart 200 (step 310 ). When the shopper 100 adds a new item to the cart, the server 140 includes the added item in the shopping cart 200 and may call the attention of the shopper 100 to items that are related to the primary items (step 315 ). The server 140 then determines whether the shopper 100 desires to add one of the related items to the shopping cart 200 (step 320 ). If the shopper 100 desires to add one of the related items to the shopping cart 200 , the server 140 includes the related item in the shopping cart 200 as a secondary item linked to the primary item (step 325 ). If the shopper 100 does not desire to add any of the related items to the shopping cart, the server 140 returns to await the next shopping command (step 300 ).
[0024] Otherwise (i.e., the shopper 100 is not adding a new primary item to the shopping cart 200 , and is therefore by default changing an attribute of a primary item already in the shopping cart 200 ), the server 140 attempts to identify any secondary items then in the shopping cart 200 that are linked to the primary item being changed (step 330 ). If no such secondary items are found, the server returns to await the next shopping command (step 300 ).
[0025] Otherwise (i.e., a secondary item that is linked to the primary item being changed is found in the shopping cart 200 ), the server 140 optionally solicits authorization of the shopper 100 to change the corresponding attribute of the secondary item responsive to the change in the attribute of the primary item (step 335 ). If the shopper denies authorization, the server 140 returns to await the next shopping command (step 300 ). Otherwise (i.e., the shopper 100 grants authorization), the server 140 changes the corresponding attribute of the secondary item responsive to the change in the attribute of the primary item (step 340 ), and then returns to await the next shopping command (step 300 ). The shopper may grant authorization explicitly in response to the server's request, or implicitly by entering a “submit” command that may be responsive to either the change in the attribute of the primary item or the proposed change in the attribute of the secondary item.
[0026] The attribute of the primary item and the corresponding attribute of the secondary item may be, for example, the quantity of the item in the shopping cart 200 , the size of the item, the color of the item, the texture of the item, and so forth. The foregoing list of attributes is to be construed as illustrative of the present invention rather than limiting, and is included here for clarity of description rather than limitation.
[0027] In one embodiment of the invention, the corresponding attribute of the secondary item is altered to match the attribute of the primary item (step 340 ). For example, if the quantity K of the primary item are in the shopping cart 200 , then the server 140 will put the quantity K of the secondary item into the shopping cart 200 . Likewise, if the primary item is green, the secondary item will also be green, and if the size of the primary item is X, then the size of the secondary item is appropriate to match size X. The present invention is not so limited, however, and other rules may be used when altering the corresponding attribute of the secondary item in response to change in the attribute of the primary item. For example, two alkaline D-cells rather than one may be added to the shopping cart 200 for every flashlight included in the shopping cart 200 , pink bath towels may be matched with green washcloths, and so forth, as the merchant 130 desires.
[0028] From the foregoing description, those skilled in the art will appreciate that the present invention helps an on-line shopper to maintain the proper relationship in a shopping cart between primary items and secondary items that are normally ordered along with the primary items, so that the on-line merchant may fill the shopper's order as the shopper intends, and so that the shopper maintains confidence in the on-line shopping process. The foregoing description, however, is illustrative rather than limiting, and the scope of the present invention is limited only by the following claims. | A method and system for managing an electronic commerce (e-commerce) shopping cart relating to communication between a shopper and a server over a communication network. A server whether a shopping command of the shopper has changed an attribute of a primary item in the shopping cart. After the server has determined that the shopping command has changed the attribute of the primary item in the shopping cart, the server identifies a secondary item in the shopping cart linked to the primary item. The server changes a corresponding attribute of the secondary item in response to the change in the attribute of the primary item, wherein the attribute of the primary item is a quantity of the primary item, a color of the primary item, or a size of the primary item. | 6 |
TECHNICAL FIELD OF THE INVENTION
[0001] This invention relates, in general, to equipment utilized in conjunction with operations performed in subterranean wells and, in particular, to a packer assembly having sequentially operated hydrostatic pistons for interventionless setting of multiple seal assemblies.
BACKGROUND OF THE INVENTION
[0002] Without limiting the scope of the present invention, its background will be described in relation to setting packers, as an example.
[0003] In the course of preparing a subterranean well for hydrocarbon production, one or more packers are commonly installed in the well. The purpose of the packers is to support production tubing and other completion equipment and to provides a seal in the well annulus between the outside of the production tubing and the inside of the well casing to isolate fluid and pressure thereacross.
[0004] Certain production packers are set hydraulically by establishing a differential pressure across a setting piston. Typically, this is accomplished by running a tubing plug on wireline, slick line, electric line, coiled tubing or another conveyance into the production tubing to a profile location. Fluid pressure within the production tubing may then be increased, thereby creating a pressure differential between the fluid within the production tubing and the fluid in the wellbore annulus. This pressure differential actuates the setting piston to expand the seal assembly of the production packer into sealing engagement with the casing. Thereafter, the tubing plug is retrieved to the surface such that production operations may begin.
[0005] As operators increasingly pursue production in deeper water offshore wells, highly deviated wells and extended reach wells, for example, the rig time required to set the tubing plug and thereafter retrieve the tubing plug can negatively impact the economics of the project, as well as add unnecessary complications and risks. To address these issues associated with hydraulically set packers, interventionless packer setting techniques have been developed. For example, a hydrostatically actuated setting module has been incorporated into the bottom end of a packer to exert an upward setting force on the packer piston. The hydrostatic setting module may be actuated by applying pressure to the production tubing and the wellbore at the surface, with the setting force being generated by a combination of the applied surface pressure and the hydrostatic pressure associated with the fluid column in the wellbore.
[0006] In operation, once the packer is positioned at the required setting depth, surface pressure is applied to the production tubing and the wellbore annulus until a port isolation device actuates, thereby allowing wellbore fluid to enter an initiation chamber on one side of the piston while the chamber engaging the other side of the piston remains at an evacuated pressure. This creates a differential pressure across the piston that causes the piston to move, beginning the setting process. Once the setting process begins, O-rings in the initiation chamber move off seat to open a larger flow area such that fluid entering the initiation chamber continues actuating the piston to complete the setting process. Therefore, the bottom-up hydrostatic setting module provides an interventionless method for setting packers as the setting force is provided by available hydrostatic pressure and applied surface pressure without plugs or other well intervention devices.
[0007] It has been found, however, that the bottom-up hydrostatic setting module may not be ideal for applications where the wellbore annulus and production tubing cannot be pressured up simultaneously. Such applications include, for example, when a packer is used to provide liner top isolation or when a packer is landed inside an adjacent packer in a stacked packer completion. In such circumstances, if a bottom-up hydrostatic setting module is used to set a packer above another sealing device, there is only a limited annular region between the unset packer and the previously set sealing device below. Therefore, when the operator pressures up on the wellbore annulus, the hydrostatic pressure begins actuating the bottom-up hydrostatic setting module to exert an upward setting force on the piston. When the packer sealing elements start to engage the casing, however, the limited annular region between the packer and the lower sealing device becomes closed off and can no longer communicate with the upper annular area that is being pressurized from the surface. Thus, the trapped pressure in the limited annular region between the packer and the lower sealing device is soon dissipated and may not fully set the packer.
[0008] Accordingly, a need has arisen for improved packer for providing a seal between a tubular string and a wellbore surface. In addition, a need has arisen for such an improved packer that does not require a plug to be tripped into and out of the well to enable setting. Further, a need has arisen for such an improved packer that is operable to be set without the application of both tubing pressure and annulus pressure.
SUMMARY OF THE INVENTION
[0009] The present invention disclosed herein comprises a packer assembly having sequentially operated hydrostatic pistons for interventionless setting of multiple seal assemblies that is operable to provide a seal between a tubular string and a wellbore surface. The packer assembly of the present invention does not require a plug to be tripped into and out of the well to enable setting. In addition, the packer assembly of the present invention is operable to be set without the application of both tubing pressure and annulus pressure.
[0010] In one aspect, the present invention is directed to a packer assembly for use in a wellbore. The packer assembly includes a packer mandrel. A first piston is slidably disposed about the packer mandrel defining a first chamber therewith. An activation assembly is disposed about the packer mandrel initially preventing movement of the first piston. A first seal assembly is disposed about the packer mandrel and is operably associated with the first piston. A second piston is slidably disposed about the packer mandrel defining a second chamber therewith. A release assembly is disposed about the packer mandrel initially preventing movement of the second piston. A second seal assembly is disposed about the packer mandrel and is operably associated with the second piston such that actuation of the activation assembly allows a force generated by a pressure difference between the wellbore and the first chamber to shift the first piston in a first direction toward the first seal assembly to radially expand the first seal assembly and to actuate the release assembly and such that actuation of the release assembly allows a force generated by a pressure difference between the wellbore and the second chamber to shift the second piston in the first direction toward the second seal assembly to radially expand the second seal assembly.
[0011] In some embodiments, the activation assembly may include a housing section at least partially disposed about the packer mandrel that defines an activation chamber with the packer mandrel and the first piston. In these embodiments, a pressure actuated element may be positioned in a fluid flow path between the wellbore and the activation chamber initially preventing fluid flow therethrough until wellbore pressure exceeds a predetermined actuation pressure. Also, in these embodiments, a frangible member may initially couple the first piston to the housing section. In certain embodiments, the release assembly may include a release sleeve disposed about the packer mandrel that is operably associated with the first seal assembly. In these embodiments, a collet assembly may be disposed about the packer mandrel that initially prevents movement of the second piston. Also, in these embodiments, a frangible member may initially couple the release sleeve to the packer mandrel. In one embodiment, a first body lock ring disposed about the packer mandrel may be operable to prevent release of the first seal assembly after radial expansion of the first seal assembly. In other embodiments, at least one second body lock ring disposed about the packer mandrel may be operable to prevent release of the second seal assembly after radial expansion of the second seal assembly.
[0012] In another aspect, the present invention is directed to a method for setting a packer assembly in a wellbore. The method includes providing a packer assembly having a packer mandrel with first and second seal assemblies disposed thereabout; running the packer assembly into the wellbore; preventing movement of a first piston toward the first seal assembly with an activation assembly disposed about the packer mandrel; preventing movement of a second piston toward the second seal assembly with a release assembly disposed about the packer mandrel; actuating the activation assembly to allow a force generated by a pressure difference between the wellbore and a first chamber defined between the first piston and the packer mandrel to shift the first piston in a first direction toward the first seal assembly to radially expand the first seal assembly; and actuating the release assembly responsive to the shifting of the first piston to allow a force generated by a pressure difference between the wellbore and a second chamber defined between the second piston and the packer mandrel to shift the second piston in the first direction toward the second seal assembly to radially expand the second seal assembly.
[0013] The method may also include bursting a pressure actuated element responsive to an increase in wellbore pressure to a predetermined actuation pressure, pressurizing an activation chamber disposed between a housing section, the packer mandrel and the first piston, exposing a first piston area of the first piston to wellbore pressure, breaking a frangible member coupling the first piston to the housing section, breaking a frangible member coupling a release sleeve to the packer mandrel, radially inwardly compressing a collet assembly with the release sleeve and/or unlatching the second piston from the collet assembly.
[0014] In a further aspect, the present invention is directed to a packer assembly for use in a wellbore. The packer assembly includes a packer mandrel. A first piston is slidably disposed about the packer mandrel defining a first chamber therewith. An activation assembly is disposed about the packer mandrel initially preventing movement of the first piston. A seal assembly is disposed about the packer mandrel and is operably associated with the first piston. A second piston is slidably disposed about the packer mandrel defining a second chamber therewith. A release assembly is disposed about the packer mandrel initially preventing movement of the second piston such that actuation of the activation assembly allows a force generated by a pressure difference between the wellbore and the first chamber to shift the first piston in a first direction toward the seal assembly to radially expand the seal assembly and to actuate the release assembly and such that actuation of the release assembly allows a force generated by a pressure difference between the wellbore and the second chamber to shift the second piston in the first direction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying figures in which corresponding numerals in the different figures refer to corresponding parts and in which:
[0016] FIG. 1 is a schematic illustration of an offshore platform operating a plurality of packer assemblies having sequentially operated hydrostatic pistons for interventionless setting of multiple seal assemblies in accordance with an embodiment of the present invention;
[0017] FIGS. 2A-2F are cross-sectional views of consecutive axial sections of a packer assembly having sequentially operated hydrostatic pistons for interventionless setting of multiple seal assemblies in accordance with an embodiment of the present invention in its running configuration;
[0018] FIGS. 3A-3F are cross-sectional views of consecutive axial sections of a packer assembly having sequentially operated hydrostatic pistons for interventionless setting of multiple seal assemblies in accordance with an embodiment of the present invention during the setting process; and
[0019] FIGS. 4A-4F are cross-sectional views of consecutive axial sections of a packer assembly having sequentially operated hydrostatic pistons for interventionless setting of multiple seal assemblies in accordance with an embodiment of the present invention in a set configuration.
DETAILED DESCRIPTION OF THE INVENTION
[0020] While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts, which can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the present invention.
[0021] Referring initially to FIG. 1 , a plurality of packer assemblies having sequentially operated hydrostatic pistons for interventionless setting of multiple seal assemblies are being installed in an offshore oil or gas well that is schematically illustrated and generally designated 10 . A semi-submersible platform 12 is centered over a submerged oil and gas formation 14 located below sea floor 16 . A subsea conduit 18 extends from deck 20 of platform 12 to wellhead installation 22 , including blowout preventers 24 . Platform 12 has a hoisting apparatus 26 and a derrick 28 for raising and lowering pipe strings, such as work string 30 .
[0022] A wellbore 32 extends through the various earth strata including formation 14 . A casing 34 is secured within a vertical section of wellbore 32 by cement 36 . An upper end of a liner 38 is secured to the lower end of casing 34 by a suitable liner hanger. Note that, in this specification, the terms “liner” and “casing” are used interchangeably to describe tubular materials, which are used to form protective linings in wellbores. Liners and casings may be made from any material such as metals, plastics, composites, or the like, may be expanded or unexpanded as part of an installation procedure. Additionally, it is not necessary for a liner or casing to be cemented in a wellbore.
[0023] Work string 30 may include one or more packer assemblies 40 , 42 , 44 , 46 , 48 of the present invention that may be located proximal to the top of liner 38 or as part of the completion to provide zonal isolation. Packer assemblies 40 , 42 , 44 , 46 , 48 include sequentially operated hydrostatic pistons for interventionless setting of multiple seal assemblies. When set, packer assemblies 40 , 42 , 44 , 46 isolate zones of the annulus between wellbore 32 and completion string, while packer assembly 48 provides a seal between tubular string 30 and casing 34 . In addition, the completion includes sand control screen assemblies 50 , 52 , 54 that are located substantially proximal to formation 14 . As shown, packer assemblies 40 , 42 , 44 , 46 may be located above and below each set of sand control screen assemblies 50 , 52 , 54 . In this manner, formation fluids from formation 14 may enter sand control screen assemblies 50 , 52 , 54 between packer assemblies 40 , 42 , between packer assemblies 42 , 44 and between packer assemblies 44 , 46 , respectively.
[0024] Even though FIG. 1 depicts the packer assemblies of the present invention in a slanted wellbore, it should be understood by those skilled in the art that the present invention is equally well suited for use in wellbores having other directional configurations including vertical wellbore, horizontal wellbores, deviated wellbores, multilateral wells and the like. Accordingly, it should be understood by those skilled in the art that the use of directional terms such as above, below, upper, lower, upward, downward, uphole, downhole and the like are used in relation to the illustrative embodiments as they are depicted in the figures, the upward direction being toward the top of the corresponding figure and the downward direction being toward the bottom of the corresponding figure, the uphole direction being toward the surface of the well and the downhole direction being toward the toe of the well. Also, even though FIG. 1 depicts an offshore operation, it should be understood by those skilled in the art that the packer assemblies of the present invention are equally well suited for use in onshore operations.
[0025] Referring now to FIGS. 2A-2F , therein are depicted successive axial sections of a packer assembly having dual hydrostatic pistons for redundant interventionless setting that is representatively illustrated and generally designated 100 . Packer assembly 100 includes an upper adaptor 102 that may be threadably coupled to another downhole tool or tubular as part of a tubular string as described above. At its lower end, upper adaptor 102 is threadably coupled to an upper end of packer mandrel 104 . In the illustrated embodiment, packer mandrel 104 includes an upper packer mandrel section 106 , an upper intermediate mandrel section 108 , a lower intermediate mandrel section 110 and a lower mandrel section 112 , each of which is threadably coupled to the adjacent sections. Packer assembly 100 includes a lower adaptor 114 that is threadably coupled to a lower end of packer mandrel 104 and that may be threadably coupled to another downhole tool or tubular at its lower end to form part of a tubular string as described above.
[0026] Packer mandrel 104 includes a plurality of receiving profiles 116 , 118 , 120 , 122 , 124 , 126 . Packer mandrel 104 also includes a plurality of sealing profiles 128 , 130 , 132 , 134 , each of which includes multiple sealing elements such as O-rings or other packing elements. Positioned around an upper portion of packer mandrel 104 is an upper housing section 136 . Upper housing section 136 includes a connection ring 138 , an upper connector 140 and an upper activation assembly 142 that is threadably coupled to upper connector 140 . Upper activation assembly 142 includes a sealing profile 144 having multiple sealing elements to provide sealing engagement with packer mandrel 104 . Upper activation assembly 142 and packer mandrel 104 form an upper activation chamber 146 therebetween. Upper activation assembly 142 includes one or more radial fluid passageways 148 that are depicted as having pressure actuated elements such as rupture disks 150 disposed therein in FIG. 2A . Upper activation assembly 142 also includes a pin groove 152 and a sealing profile 154 having multiple sealing elements.
[0027] Slidably disposed about packer mandrel 104 is an upper piston 156 that includes a plurality of threaded openings 158 and has a sealing profile 160 having multiple sealing elements. Upper piston 156 is initially coupled to upper activation assembly 142 by a plurality of frangible members depicted a shear screws 162 . In this configuration shown in FIG. 2A , activation chamber 146 is defined between upper piston 156 , upper activation assembly 142 and packer mandrel 104 . At its lower end, upper piston 156 is threadably coupled to a body lock assembly 164 that includes a body lock ring 166 having teeth located along its inner surface for providing a gripping arrangement with packer mandrel 104 . A seal assembly 168 , depicted as expandable seal elements 170 , 172 , 174 , is slidably positioned around packer mandrel 104 between body lock assembly 164 and a release assembly 176 . In the illustrated embodiment, even though three expandable seal elements 170 , 172 , 174 are depicted and described, those skilled in the art will recognizes that a seal assembly of the packer of the present invention may have an alternate design including any number of seal elements.
[0028] Release assembly 176 includes a release sleeve 178 and a collet assembly 180 . Release sleeve 178 is initially coupled to packer mandrel 104 by a plurality of frangible members depicted shear screws 182 . Collet assembly 180 is supported between a pair of connection rings 184 , 186 . Collet assembly 180 is initially coupled to an upper intermediate piston 188 that has a sealing profile 190 having multiple sealing elements. At its lower end, upper intermediate piston 188 is threadably coupled to a body lock assembly 192 that includes a body lock ring 194 having teeth located along its inner surface for providing a gripping arrangement with packer mandrel 104 . A seal assembly 196 , depicted as expandable seal elements 198 , 200 , 202 , is slidably positioned around packer mandrel 104 between body lock assembly 192 and a body lock assembly 204 that includes a body lock ring 206 having teeth located along its inner surface for providing a gripping arrangement with packer mandrel 104 . In the illustrated embodiment, even though three expandable seal elements 198 , 200 , 202 are depicted and described, those skilled in the art will recognizes that a seal assembly of the packer of the present invention may have an alternate design including any number of seal elements.
[0029] At its lower end, body lock ring 204 is threadably coupled to a lower intermediate piston 208 that has a sealing profile 210 having multiple sealing elements. Lower intermediate piston 208 is initially coupled to a release assembly 212 . Release assembly 212 includes a release sleeve 214 and a collet assembly 216 . Release sleeve 214 is initially coupled to packer mandrel 104 by a plurality of frangible members depicted shear screws 218 . Collet assembly 216 is supported between a pair of connection rings 220 , 222 . A seal assembly 224 , depicted as expandable seal elements 226 , 228 , 230 , is slidably positioned around packer mandrel 104 between release assembly 214 and a body lock assembly 232 that includes a body lock ring 234 having teeth located along its inner surface for providing a gripping arrangement with packer mandrel 104 . In the illustrated embodiment, even though three expandable seal elements 226 , 228 , 230 are depicted and described, those skilled in the art will recognizes that a seal assembly of the packer of the present invention may have an alternate design including any number of seal elements.
[0030] At its lower end, body lock assembly 232 is threadably coupled to a lower piston 236 that has a sealing profile 238 having multiple sealing elements and a plurality of threaded openings 240 . Positioned around a lower portion of packer mandrel 104 is a lower housing section 242 . Lower housing section 242 includes a connection ring 244 , a lower connector 246 and a lower activation assembly 248 that is threadably coupled to lower connector 246 . Lower activation assembly 248 includes a sealing profile 250 having multiple sealing elements to provide sealing engagement with packer mandrel 104 . Lower activation assembly 248 and packer mandrel 104 form a lower activation chamber 252 therebetween. Lower activation assembly 248 includes one or more radial fluid passageways 254 that are depicted as having pressure actuated elements such as rupture disks 256 disposed therein in FIG. 2E . Lower activation assembly 248 also includes a pin groove 258 and a sealing profile 260 having multiple sealing elements. Lower piston 236 is initially coupled to lower activation assembly 248 by a plurality of frangible members depicted shear screws 262 . In this configuration shown in FIG. 2F , lower activation chamber 252 is defined between lower piston 236 , lower activation assembly 248 and packer mandrel 104 .
[0031] As best seen in FIG. 2B , an atmospheric chamber 264 is disposed between upper piston 156 and packer mandrel 104 and more particularly between sealing profile 160 of upper piston 156 and sealing profile 128 of packer mandrel 104 . As best seen in FIG. 2C , an atmospheric chamber 266 is disposed between upper intermediate piston 188 and packer mandrel 104 and more particularly between sealing profile 190 of upper intermediate piston 188 and sealing profile 130 of packer mandrel 104 . As best seen in FIG. 2D , an atmospheric chamber 268 is disposed between lower intermediate piston 208 and packer mandrel 104 and more particularly between sealing profile 210 of lower intermediate piston 208 and sealing profile 132 of packer mandrel 104 . As best seen in FIG. 2E , an atmospheric chamber 270 is disposed between lower piston 236 and packer mandrel 104 and more particularly between sealing profile 238 of lower piston 236 and sealing profile 134 of packer mandrel 104 . Preferably, atmospheric chambers 264 , 266 , 268 , 270 are initially evacuated by pulling a vacuum.
[0032] Referring collectively to FIGS. 2A-2F , 3 A- 3 F and 4 A- 4 F, the operation of packer assembly 100 will now be described. Packer assembly 100 is shown before, during and after activation and expansion of seal assemblies 168 , 196 , 224 , respectively, in FIGS. 2A-2F , 3 A- 3 F and 4 A- 4 F. Packer assembly 100 may be run into a wellbore on a work string or similar tubular string to a desired depth and then set against a casing string, a liner string or other wellbore surface including an open hole surface. It is noted that during run in, movement of upper piston 156 is initially prevented as upper piston 156 is initially coupled to upper activation assembly 142 by shear screws 162 and due to the presence of rupture disks 150 in fluid passageways 148 of upper activation assembly 142 which prevent fluid pressure from entering upper activation chamber 146 . Movement of upper intermediate piston 188 is initially prevented by release assembly 176 as release sleeve 178 is initially coupled to packer mandrel 104 by shear screws 182 and collet assembly 180 is initially coupled to upper intermediate piston 188 . Movement of lower intermediate piston 208 is initially prevented by release assembly 212 as release sleeve 214 is initially coupled to packer mandrel 104 by shear screws 218 and collet assembly 216 is initially coupled to lower intermediate piston 208 . Movement of lower piston 236 is initially prevented as lower piston 236 is initially coupled to lower activation assembly 248 by shear screws 262 and due to the presence of rupture disks 256 in fluid passageways 254 of lower activation assembly 248 which prevent fluid pressure from entering lower activation chamber 252 .
[0033] Setting a accomplished by increasing the wellbore or annulus pressure surrounding packer assembly 100 to an actuation pressure sufficient to substantially simultaneously or sequentially burst rupture disks 150 , 256 . For example, when the actuation pressure of rupture disks 256 is reached and rupture disks 256 burst, fluid pressure from the wellbore enters activation chamber 252 via fluid passageway 254 . The force generated by the fluid pressure acting on a lower surface of lower piston 236 breaks the shear screws 262 allowing lower piston 236 to move upwardly against any opposing force generated by pressure within atmospheric chamber 270 , which is preferably negligible. Lower piston 236 moves together with body lock assembly 232 to apply a compressive force against seal assembly 224 . When the compressive force reaches a predetermined level, shear screws 218 break allowing release sleeve 214 to shift upwardly relative to packer mandrel 104 . The upwardly moving release sleeve 214 contacts collet assembly 216 causing radial retraction of the collet fingers of collet assembly 216 , decoupling collet assembly 216 from lower intermediate piston 208 , as best seen in FIG. 3D .
[0034] Preferably, at the same time, when the actuation pressure of rupture disks 150 is reached and rupture disks 150 burst, fluid pressure from the wellbore enters activation chamber 146 via fluid passageway 148 . The force generated by the fluid pressure acting on an upper surface of upper piston 156 breaks the shear screws 162 allowing upper piston 156 to move downwardly against any opposing force generated by pressure within atmospheric chamber 264 , which is preferably negligible. Upper piston 156 moves together with body lock assembly 164 to apply a compressive force against seal assembly 168 . When the compressive force reaches a predetermined level, shear screws 182 break allowing release sleeve 178 to shift downwardly relative to packer mandrel 104 . The downwardly moving release sleeve 178 contacts collet assembly 180 causing radial retraction of the collet fingers of collet assembly 180 , decoupling collet assembly 180 from upper intermediate piston 188 , as best seen in FIG. 3C .
[0035] Thereafter, the hydrostatic pressure in the wellbore acts on lower piston 236 , lower intermediate piston 208 , upper piston 156 and upper intermediate piston 188 . Specifically, the hydrostatic pressure continues to act on a lower surface of lower piston 236 to upwardly shift lower piston 236 relative to packer mandrel 104 . This upward movement shifts body lock assembly 232 , seal assembly 224 and release sleeve 214 until further upward movement of release sleeve 214 is limited by connection ring 222 . A compressive force is then applied to seal assembly 224 between body lock assembly 232 and release sleeve 214 which causes radial expansion of seal elements 226 , 228 , 230 , as best seen in FIG. 4E . The hydrostatic pressure also continues to act on an upper surface of upper piston 156 to downwardly shift upper piston 156 relative to packer mandrel 104 . This downward movement shifts body lock assembly 164 , seal assembly 168 and release sleeve 178 until further downward movement of release sleeve 178 is limited by connection ring 184 . A compressive force is then applied to seal assembly 168 between body lock assembly 164 and release sleeve 178 which causes radial expansion of seal elements 170 , 172 , 174 , as best seen in FIG. 4B .
[0036] In addition, the hydrostatic pressure now acts on a lower surface of lower intermediate piston 208 operating against any opposing force generated by pressure within atmospheric chamber 268 , which is preferably negligible. This upward movement of lower intermediate piston 208 shifts body lock assembly 204 . At the same time, the hydrostatic pressure acts on an upper surface of upper intermediate piston 188 operating against any opposing force generated by pressure within atmospheric chamber 266 , which is preferably negligible. This downward movement of upper intermediate piston 188 shifts body lock assembly 192 . The simultaneous upward movement of body lock assembly 204 and downward movement of body lock assembly 192 applies a compressive force against seal assembly 196 which causes radial expansion of seal elements 198 , 200 , 202 , as best seen in FIG. 4C .
[0037] In this manner, actuation of activation assembly 248 causes the sequential operation of lower piston 236 and lower intermediate piston 208 to set seal assemblies 224 , 196 . Likewise, actuation of activation assembly 142 causes the sequential operation of upper piston 156 and upper intermediate piston 188 to set seal assemblies 168 , 196 . Even though packer assembly 100 has been described as sequentially operating two pistons responsive to actuation of an activation assembly, it should be understood by those skilled in the art that any number of pistons could alternatively be operated in a sequential manner, for example, using multiple release assembly stages, without departing from the principle of the present invention. Once set, the sealing and gripping relationship between seal assembly 224 and the wellbore setting surface is maintained by body lock ring 234 , which prevents loss of compression on seal assembly 224 . Likewise, the sealing and gripping relationship between seal assembly 168 and the wellbore setting surface is maintained by body lock ring 166 which prevents loss of compression on seal assembly 168 . Similarly, the sealing and gripping relationship between seal assembly 196 and the wellbore setting surface is maintained by body lock rings 194 , 206 which prevent loss of compression on seal assembly 224 . In this configuration, wellbore pressure above packer assembly 100 tends to further compress seal assembly 168 due to the downward force applied on upper piston 156 . Likewise, wellbore pressure below packer assembly 100 tends to further compress seal assembly 224 due to the upward force applied on lower piston 236 . Further, if a leak were to develop relative to seal assembly 168 , wellbore pressure above packer assembly 100 would tend to further compress seal assembly 196 due to the downward force applied on upper intermediate piston 188 . Likewise, if a leak were to develop relative to seal assembly 224 , wellbore pressure below packer assembly 100 would tend to further compress seal assembly 196 due to the upward force applied on lower intermediate piston 208 .
[0038] While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments as well as other embodiments of the invention will be apparent to persons skilled in the art upon reference to the description. It is, therefore, intended that the appended claims encompass any such modifications or embodiments. | A packer for use in a wellbore includes a packer mandrel. First and second pistons are slidably disposed about the packer mandrel defining first and second chambers therewith. An activation assembly initially prevents movement of the first piston. A release assembly initially prevents movement of the second piston. First and second seal assemblies are disposed about the packer mandrel such that actuation of the activation assembly allows a force generated by a pressure difference between the wellbore and the first chamber to shift the first piston in a first direction toward the first seal assembly to radially expand the first seal assembly and to actuate the release assembly and, actuation of the release assembly allows a force generated by a pressure difference between the wellbore and the second chamber to shift the second piston in the first direction toward the second seal assembly to radially expand the second seal assembly. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to a fire retardant adhesive tissue and a method of manufacture, and more particularly to a fire retardant tissue paper which has been treated with a dispersion of fire retardant and adhesive to provide a tissue with the fire retardant solids disbursed within the tissue paper and adhesive dots on the surface.
Tissue paper is utilized in a wide variety of industrial applications. One such application is as a portion of a laminate utilized in automobiles for improving sound insulation. In addition to its sound insulation properties, it is highly desirable that the tissue paper be treated with a flame retardant so that the final product will be flame retardant and still have good acoustic properties when in composite form.
Tissue paper typically used in automotive applications is of a grade that has a weight of between about 17 to 21 g/m 2 (0.5 to 0.6 oz/yd 2 ). This is a difficult material to work with due to the extremely low tensile strength of the material. Since many flame retardant solids are provided in aqueous solutions, once the fragile tissue paper is wetted, it would tend to tear when being transported through the manufacturing process. Further, it is desirable not to have to apply the flame retardant and the adhesive in separate operations due to the fragile nature of the materials. Various processing options are available. This includes hot melt coating to apply the adhesive without causing the paper to become brittle or degrading the cellulose in the paper.
In view of the difficulty in handling a low tensile strength material such as tissue paper, it is highly desirable to provide a flame retardant adhesive tissue paper which can be manufactured without degrading the paper and which will overcome the processing difficulties in the prior art. Such a flame retardant adhesive tissue finds particular utility in automotive application where such papers are utilized in various vehicle interior laminates.
SUMMARY OF THE INVENTION
Generally speaking, in accordance with the invention, a flame retardant adhesive tissue paper for fabricating moldable structures and methods of fabrication of the tissue paper are provide. The flame retardant adhesive tissue paper is prepared by applying an aqueous paste dispersion including a flame retardant and thermoplastic adhesive dispersed therein to the surface of the paper using a printing screen. This coating adds 25 to 50% dry solids on the surface based on the weight of the paper. The amount of paste coating applied to the paper is controlled by the pumping speed of the dispersion to the screen-print head and the transport speed of the paper past the print head.
When an aqueous paste dispersion is screen printed onto the tissue paper and dried, the flame retardant solids in the paste dispersion wet out the paper leaving the adhesive dots on the surface of the paper. This causes the flame retardant solids to be soaked into the cellulosic material and impart flame retardant properties to the adhesive coated paper. After application of the dispersion, the paper goes through a forced air oven at controlled speed to dry off the water.
After drying, the flame retardant solids and polymer adhesives stay behind on the paper. After all the water is removed, oven temperature is increased to activate the polymer adhesive causing it to flow and adhere to the paper. As the coated paper leaves the oven, it is batched on rolls and ready for shipment.
Accordingly, it is an object of the invention to provide a tissue paper which has added flame retardant properties and thermoplastic adhesive dots on its surface.
Another object of the invention is to provide an improved flame retardant adhesive tissue paper including dots of thermoplastic adhesive on the surface and flame retardant solids dispersed in the cellulose material
A further object of the invention is to provide a process for preparing a flame retardant adhesive tissue paper having a weight about 15.5 to 22.0 g/m 2 (0.45 to 0.65 oz/yd 2 ).
Yet another object of the invention is to provide an improved flame retardant adhesive tissue paper wherein the flame retardant solids are dispersed within the cellulosic material of the tissue paper.
Yet a further object of the invention is to provide a flame retardant adhesive tissue wherein the flame retardant solids are dispersed within the tissue and the adhesive dots on the surface are of polyester.
Still a further object of the invention is to provide a method for preparing a flame retardant adhesive tissue without damaging tissue paper.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.
The invention, accordingly comprises an article possessing the characteristics, properties and relation of constituent, and the several steps of one of more of such steps with respect to each of the others, all as exemplified in the detailed disclosure hereinafter setforth, and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the invention, references is had to the following description taken in connection with the accompanying drawings, in which:
FIG. 1 is a perspective view of a length of fire retardant adhesive tissue paper constructed and arranged in accordance with the invention;
FIG. 2 is a schematic view illustrating the process steps and equipment utilized in accordance with the invention to fabricate the flame retardant adhesive tissue of FIG. 1; and
FIG. 3 is an enlarged view of the rotating doctor blade of the screen print coating head in the apparatus of FIG. 2 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A flame retardant adhesive tissue paper 11 constructed and arranged in accordance with the invention is shown in perspective in FIG. 1 . Tissue paper 11 is formed of a base starting tissue paper 12 of fibers 13 , such as cellulose fiber used in conventional tissue papers. Tissue paper 11 includes a plurality of adhesive dots arranged in a discontinuous coating, either in a geometric or random pattern on the upper surface thereof. The spots may be in a regular shape or form, such as dots 14 . Flame retardant particles 16 are dispersed within tissue paper 12 between cellulose fibers 13 .
The uncoated weight of tissue paper 12 before going through the process in accordance with the invention, is between about 14.6 to 22.0 g/m 2 (0.43 to 0.65 oz/yd 2 ). Such paper is available from a variety of paper manufacturers and is known as an 11 pound paper in the U.S. paper industry. This designation is utilized instead of reporting the weigh in or g/m 2 or oz/yd 2 . This means that the tissue paper weighs 5 kilograms per 279 square meters (11 pounds per 3,000 square feet).
The tensile strength of dry tissue paper 12 in the machine direction is between about 500 to 1,200 g/in. Tensile strength in the transverse direction is between about 200 to 550 g/in. Preferably, the wet tensile strength in the machine direction is targeted to be between about 350 to 450 g/in. A wet strength lower than 250 g/in is not desirable, but a higher wet machine direction tensile strength is acceptable.
Tissue paper 11 is light and stretches considerably. The stretch of a dry tissue in the machine direction at break is about 17.5 to 25%. Porosity is targeted at 38.1 cm 2 s/sq (75ft. 3 /Min/ft 2 ) and is in the range of between about 30.5 to 45.7 cm 3 /s/sq (60 to 90 ft. 3 /min/ft 2 ). Such a paper is suitable for internal automotive use due to its wet strength in the machine direction and for the porosity properties. Generally, tissue paper 11 must be free from pin holes and or other defects that may be detrimental to the acoustic properties of the final product.
Once tissue paper 12 is ready for treatment, it is treated using a screen printing apparatus 21 as illustrated in schematic FIG. 2 . Here paper 11 is coated with a paste using a 17 R-screen. This supplies approximately 52 dots/cm 2 . in a geometric or random arrangement, hence the “R” screen name designation refers to a screen applying a random pattern. Such a screen is also referred to as a random 17-mesh screen.
When coating tissue paper 17 , the amount of material added during the coating operation is dependent upon the speed of transport of tissue paper 12 and the pumping speed of the paste dispersion. It has been found that it is desirable to apply between about 150% to 250% by weight wet paste pick up or about 8.5 to 59.3 g/m 2 (0.25 to 1.75 oz/yd 2 ) wet paste when leaving the paste-coating head region of the line. This amount of coating leaves between about 0.15 to 0.75 oz/yd 2 of dry solids on the paper. Depending upon the concentration of solids in the dispersion, the flame retardants added to the paper will be between about 5.1 to 8.5 g/m 2 (0.05 to 0.25 oz/yd 2 ). This amounts to about 15 to 25% flame retardant solids on finished paper 12 . The remaining solids of between about 1.7 and 8.5 g/m 2 (0.15 and 0.25 oz/yd 2 ) are the polymer adhesives dots on the surface.
As noted above the amount of paste coating applied to tissue paper 11 is controlled by the speed of the pump that pumps the paste dispersion to the screen printing head. The speed of the pump is subjectively controlled by measuring the total weight of the coated paper level which allows adjustment of the level paste to the screen printing head.
When a paste dispersion is applied to the surface of tissue paper 11 , flame retardant solids 16 in the paste dispersion wet out the paper leaving adhesive dots 14 on the surface of tissue paper 11 . Because flame retardant solids 16 are soaked into tissue paper 11 between cellulose fibers 14 , flame retardant solids 16 impart flame retardant properties to finished adhesive coated paper 11 .
After application of the paste dispersion, tissue paper 12 passes through ovens at a controlled rate of speed. The speed of tissue paper 12 is controlled to be between about 16 to 42 m/min (18 to 45 yds/min). Here, water in the paste dispersion is driven off by blowing forced hot air through the oven. Flame retardant solids 16 and adhesive dots 13 stay behind on the paper substrate. Flame retardant solids 16 get trapped within cellulose fibers 14 forming the structure of tissue paper 12 , while adhesive power dots 13 remain on top of the surface of tissue paper 12 . After all the water has dried, the temperature of the oven is increased to at least a temperature that activates the polymer adhesive powder. In the case of a polyester powder adhesive, this temperature is between about 135° to 177° C. (275° to 350° F.). The polymer then flows and adheres to surface of tissue paper 12 . If water was only dried and the adhesive dots not activated, the adhesive powder would not stick to tissue paper 12 and would be easily removed.
After coating and drying, coated tissue paper 11 leaves the oven station and is packaged accordingly to customer specifications, such as rolls ready for shipment.
Referring specifically to FIG. 2 screen paste rotating apparatus 21 utilized to fabricate coated tissue paper 11 is shown in schematic. Here, a roll of uncoated tissue paper 22 mounted on an uncoated tissue dolly 23 is positioned at the input side of screen paste coating unit 21 . Tissue paper 22 is fed through a series of handling rollers 24 and directed past a paste print head assembly 26 . Paste print head assembly 26 includes a print head 27 shown in more detail in FIG. 3 . Paste print head assembly 26 also includes a control panel 28 for regulating the amount of paste dispersion stored in a reservoir 29 to be pumped to paste print head assembly 27 .
After passing through paste print head 26 , tissue paper 22 is fed over an oven feed roller 31 and enters an oven 32 in which hot air is circulated therethrough. Water in the fire retardant paste dispersion is driven off in oven 32 . After the water has been removed from tissue paper 22 in oven 32 , the temperature in oven 32 is increased to between about 135° to 177° C. (275° to 350° F.) to activate the polyester thermoplastic adhesive. The specific temperature selected is dependent on line speed. This causes the resin to flow and adhere to the surface of tissue paper 22 . Tissue paper 22 is then passed over a series of cooling rollers 33 after which it is fed onto a pickup roll 34 also mounted on a dolly 36 .
In FIG. 3, the details of the screen print head 27 in paste dot head assembly 26 are shown in more detail. Tissue paper 22 is shown being fed between a pair of print feed rollers 37 and 38 . At this time, tissue paper 22 passes below a print screen 39 having a plurality of screen printing holes 41 . The quantity of flame retardant paste dispersion is fed by a doctor 43 and forced through holes 41 by a rotating doctor blade 44 mounted in doctor 43 as tissue paper 22 is transported beyond screen 39 . A plurality of fire retardant paste dispersion dots 46 remain on the upper surface of tissue paper 22 .
After exiting paste print head assembly 26 , tissue paper 22 passes over an oven feed roller 31 and is fed into a forced air oven 32 . Here, the temperature of oven 32 is controlled to dry tissue paper 22 with fire retardant paste dispersion dots 46 on the surface. After drying, tissue paper 22 is heated to activate the polyester adhesive and tissue paper 22 then exists oven 32 and passes over a series of cooling rollers 33 where tissue paper 22 is cooled. At this point, the coating process is complete and coated tissue 22 is then wound on the take-up rolls 34 mounted on dolly 36 on the exit of screen paste coating unit 21 .
As tissue paper 22 passes through oven 22 the speed is controlled at between about 16 to 42 m/min (18 to 45 yds/min). After all the water is removed, the temperature of oven 32 is increased to about 135° to 154° C. (275° to 310° F.). This activates the polymer adhesives which then flows and adheres to the surface of tissue paper 11 . It has been found that if water is merely removed from tissue paper 22 and adhesive dots 46 are not activated, the polymer would not stick to the surface of tissue paper 22 and would be easily removed.
The flame retardant utilized in accordance with the invention is an inorganic water soluble material. It is generally supplied in concentrations of about 50% solids. This means that when 100 parts by weight is added to a mix, actually 50 parts of flame retardant solids are added. A preferred flame retardant material is supplied by Spartan Flame Retardant, Inc. of Crystal Lake, Ill. Spartan X-12 ammonium salt flame retardant would also be suitable. Additionally, flame retardants are also available from Albright & Wilson, Richmond, Va. known as Amgard® FSD. or Amgard® CL. These are water-based ammonium phosphate flame retardants made for cellulosic material.
The thermoplastic adhesive is a fine powder having a particle size of up to about 80 microns. The thermoplastic material may be a polyamide, a low or high-density polyethylene, or a polyvinyl acetate. What is important here is the fine particle size of up to about 80 microns. One suitable thermoplastic polyester adhesive that can be used in the paste dispersion, is supplied by EMS-Chemie (North America), Inc. of Sumter, S.C. This material transfers well to the tissue paper in the paste and stays in a dot form. The melting range is between about 99° to 105° C. (210° to 221° F.) and has a melt volume rate (MVR) of 450Pa.s. EMF Griltex 1P1, a polyamide tends to function as a pressure sensitive adhesives and sticks to the paper which may be too fragile for suitable use. As noted, any thermoplastic adhesive can be utilized in the formulation so long as the particle size is less than 80 microns. This permits the adhesive to remain on the surface of the tissue paper.
A synthetic thickener used in heat sealable paste formulations may be added. It is preferable to add an anionic polyacralate emulsion. These are liquid thickening agents with a very high yield producing printing paste with high consistency and viscosity and good flow characteristics. These provide printing paste with good lubrication effect and keeps the printing screen open. It has distinct thixotropic properties and prevents smearing of the paste during screen printing stand still periods. Such materials include Mirox HP, Miraplast MS 6 and Miraplast 5147 available from Boehme Filatex, Inc. of Reidsville, N.C. Between about 3 to 8 weight percent of thickener is added to the flame retardant paste dispersion for viscosity control.
Finally, one may add a printing agent used in paste formulations, such as a non-ionic solution of ethyleneoxide adduct. Such printing agents include Mirox OX Atesynth D 1290 which stabilizes aqueous paste of heat sealed resins. The Theological behavior assures the printing paste would not lead to deposits on the outside of the print screen. It prevents penetration of the printed dot into the coated fabric. Other printing agents are available from EMS Griltex. All the desired ingredients are mixed with water prior to pumping to the print head assembly.
A typical formulation would include the following ingredients:
Ingredient
Weight %
Water
35-95
Flame Retardant Solution
20-30
Thickener
4-7
Thermoplastic Adhesive
18-26
Printing Agent
5-11
The percent solids in the final mix is between about 20 to 40 weight percent. The viscosity of the formulation, depending upon the particular adhesive and thickening agent selected should be between 2,500-3,500 cps when tested on an Brookfield RVT using a #4 spindel at 20 RPM. The viscosity is an important component of the process, because at this viscosity, the solids and the flame retardant will move and soak in between the cellulose fibers of the tissue papers. When this happens, the flame retardant solids impart flame resistant to the adhesive coated paper.
The paper is fed from supply roll 22 through apparatus 21 at between 16 to 27 m/min (18 to 30 yds/min). The paper is coated utilizing a flame retardant paste dispersion using a 17 R-4 screen. This supplies approximately 52 dots/cm 2 in a random arrangement. It has been found that due to the fragile nature of the paper, during start up, if adhesive paste dispersion is added to the paper, it tends to weaken the resulting coated tissue paper product. Accordingly, the paste print head is not activated until the base tissue paper is supplied at the speed of about 18 to 27 m/min (20 to 30 yds/min).
A 17 R-4 printing screen has 11% open surface. This is the open surface area of the dots providing an open surface and a 525 opening micron size. A wide variety of other type screens could be used, such as screens with mesh numbers 11.2, 14 and 25. Screen selection will be dependent upon viscosity of the dispersion as well as the pumping speed and tissue paper speed in the apparatus.
The following example is set forth for purposes of illustration only, and not intended to be presented in a limiting sense.
EXAMPLE 1
A flame retardant paste dispersion formulation as follows is prepared by adding ingredients under constant mixing:
Ingredient
Amount (weight %)
Water
41
Spartan FR48
22
Mirox HP (thickener)
6
EMS Griltex L365E P1 (adhesive)
22.5
Mirox OX (printing agent)
8.5
The percent solids for the final paste mix is between about 28 to 32%. The viscosity is between about 1,800 and 3,500 cps when tested on the Brookfield RVT using a #4 spindel at 20 RPM. It is anticipated that this composition will impart flame resistance to adhesive coated paper and provide flamer retardant solids of approximately 10 weight percent.
EXAMPLE 2
An uncoated tissue paper having a weight specification between 17.0 and 21.0 g/m 2 (0.50 and 0.62 oz/yd 2 ) from Cellu Tissue Corp. of Grouverneur, N.Y., and is their product Grade 3284. It is also known as 11 pound paper and is coated utilizing dispersion prepared in Example 1 in a screen paste coating apparatus illustrated in FIG. 2 . The line speed is maintained between about 18 to 23 m/min (20 to 25 yds/min) The coated dry paper after leaving the oven is batched up at the lines batcher end 2,000 yard rolls ready for shipment Flame testing is done in a composite by laminating the resulting coated tissue paper to a high loft polyester felt. It is then tested using the Federal Motorvehical Safety Standard #302 (MVSS #302) test procedure.
A flame retardant adhesive tissue in accordance with the invention provides a coated with dots of a thermoplastic adhesive and an inorganic flame retardant dispersed throughout the tissue fibers. The coated paper is particularly well suited for use in automotive doors to dampen sound.
It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in carying out the above method and in the construction(s) set forth without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.
Particularly, it is to be understood that in said claims, ingredients and compounds recited in the singular are intended to include compatible mixtures of such ingredients whatever the sense permits. | A flame retardant adhesive tissue paper for fabricating moldable structures, particularly suitable for forming laminates for the interior of automobiles is provided. The flame retardant adhesive tissue is prepared by screen printing an aqueous paste dispersion including a flame retardant and thermoplastic adhesive dispersed therein in discontinuous pattern onto one surface of the paper. After removal of water, the drying temperatures is increased to activate the thermoplastic adhesive to adhere to the surface of the tissue with the flame retardants solids dispersed within the interior of the tissue paper. The adhesive coated tissue paper has good acoustic properties and imparts flame retardancy to a laminate including it. | 2 |
CROSS-REFERENCE TO RELATED PROVISIONAL APPLICATION
[0001] This application is a Continuation of U.S. patent application Ser. No. 13/106,575, filed May 12, 2011, now U.S. Pat. No. 9,634,855, issued Apr. 25, 2017, which claims priority benefit of provisional U.S. Patent Application Ser. No. 61/334,564, entitled ELECTRONIC PERSONAL INTERACTIVE DEVICE, filed on May 13, 2010, which applications are hereby incorporated by reference in their entirety, including all Figures, Tables, and Claims.
FIELD OF THE INVENTION
[0002] The present invention relates generally to consumer electronics and telecommunications, and, more particularly, to personal devices having social human-machine user interfaces.
BACKGROUND OF THE INVENTION
[0003] Many systems and methods intended for use by elderly people are known in the art. Elderly people as a group have less developed technological skills than younger generations. These people may also have various disabilities or degraded capabilities as compared to their youth. Further, elderly people tend to be retired, and thus do not spend their time focused on an avocation.
[0004] Speech recognition technologies, as described, for example in Gupta, U.S. Pat. No. 6,138,095, incorporated herein by reference, are programmed or trained to recognize the words that a person is saying. Various methods of implementing these speech recognition technologies include either associating the words spoken by a human with a dictionary lookup and error checker or through the use of neural networks which are trained to recognize words.
[0005] See also: U.S. Pat. Nos. 7,711,569, 7,711,571, 7,711,560, 7,711,559, 7,707,029, 7,702,512, 7,702,505, 7,698,137, 7,698,136, 7,698,131, 7,693,718, 7,693,717, 7,689,425, 7,689,424, 7,689,415, 7,689,404, 7,684,998, 7,684,983, 7,684,556, 7,680,667, 7,680,666, 7,680,663, 7,680,662, 7,680,661, 7,680,658, 7,680,514, 7,676,363, 7,672,847, 7,672,846, 7,672,841, US Patent App. Nos. 2010/0106505, 2010/0106497, 2010/0100384, 2010/0100378, 2010/0094626, 2010/0088101, 2010/0088098, 2010/0088097, 2010/0088096, 2010/0082343, 2010/0082340, 2010/0076765, 2010/0076764, 2010/0076758, 2010/0076757, 2010/0070274, 2010/0070273, 2010/0063820, 2010/0057462, 2010/0057461, 2010/0057457, 2010/0057451, 2010/0057450, 2010/0049525, 2010/0049521, 2010/0049516, 2010/0040207, 2010/0030560, 2010/0030559, 2010/0030400, 2010/0023332, 2010/0023331, 2010/0023329, 2010/0010814, 2010/0004932, 2010/0004930, 2009/0326941, 2009/0326937, 2009/0306977, 2009/0292538, 2009/0287486, 2009/0287484, 2009/0287483, 2009/0281809, 2009/0281806, 2009/0281804, 2009/0271201, each of which is expressly incorporated herein by reference.
[0006] The current scholarly trend is to use statistical modeling to determine whether a sound is a phoneme and whether a certain set of phonemes corresponds to a word. This method is discussed in detail in Turner, Statistical Methods for Natural Sounds (Thesis, University of London, 2010), incorporated herein by reference. Other scholars have applied Hidden Markov Models (HMM) to speech recognitions. Hidden Markov Models are probabilistic models that assume that at any given time, the system is in a state (e.g. uttering the first phoneme). In the next time-step, the system moves to another state with a certain probability (e.g., uttering the second phoneme, completing a word, or completing a sentence). The model keeps track of the current state and attempts to determine the next state in accordance with a set of rules. See, generally, Brown, Decoding HMMs using the k best paths: algorithms and applications, BMC Bioinformatics (2010), incorporated herein by reference, for a more complete discussion of the application of HMMs.
[0007] In addition to recognizing the words that a human has spoken, speech recognition software can also be programmed to determine the mood of a speaker, or to determine basic information that is apparent from the speaker's voice, tone, and pronunciation, such as the speaker's gender, approximate age, accent, and language. See, for example, Bohacek, U.S. Pat. No. 6,411,687, incorporated herein by reference, describing an implementation of these technologies. See also, Leeper, Speech Fluency, Effect of Age, Gender and Context, International Journal of Phoniatrics, Speech Therapy and Communication Pathology (1995), incorporated herein by reference, discussing the relationship between the age of the speaker, the gender of the speaker, and the context of the speech, in the fluency and word choice of the speaker. In a similar field of endeavor, Taylor, U.S. Pat. No. 6,853,971, teaches an application of speech recognition technology to determine the speaker's accent or dialect. See also: US App. 2007/0198261, US App. 2003/0110038, and U.S. Pat. No. 6,442,519, all incorporated herein by reference.
[0008] In addition, a computer with a camera attached thereto can be programmed to recognize facial expressions and facial gestures in order to ascertain the mood of a human. See, for example, Black, U.S. Pat. No. 5,774,591, incorporated herein by reference. One implementation of Black's technique is by comparing facial images with a library of known facial images that represent certain moods or emotions. An alternative implementation would ascertain the facial expression through neural networks trained to do so. Similarly, Kodachi, U.S. Pat. No. 6,659,857, incorporated herein by reference, teaches about the use of a “facial expression determination table” in a gaming situation so that a user's emotions can be determined. See also U.S. Pat. No. 6,088,040, U.S. Pat. No. 7,624,076, U.S. Pat. No. 7,003,139, U.S. Pat. No. 6,681,032, and US App. 2008/0101660.
[0009] Takeuchi, “Communicative Facial Displays as a New Conversational Modality,” (1993) incorporated herein by reference, notes that facial expressions themselves could be communicative. Takeuchi's study compared a group of people who heard a voice only and a group of people who viewed a face saying the same words as the voice. The people who saw the face had a better understanding of the message, suggesting a communicative element in human facial expressions. Catrambone, “Anthropomorphic Agents as a User Interface Paradigm: Exponential Findings and a Framework for Research,” incorporated herein by reference, similarly, notes that users who learn computing with a human face on the computer screen guiding them through the process feel more comfortable with the machines as a result.
[0010] Lester goes even further, noting that “animated pedagogical agents” can be used to show a face to students as a complex task is demonstrated on a video or computer screen.
[0011] The computer (through the face and the speaker) can interact with the students through a dialog. Lester, “Animated Pedagogical Agents: Face-to-Face Interaction in Interactive Learning Environments,” North Carolina State University (1999), incorporated herein by reference. Cassell, similarly, teaches about conversational agents. Cassell's “embodied conversational agents” (ECAs) are computer interfaces that are represented by human or animal bodies and are lifelike or believable in their interaction with the human user. Cassell requires ECAs to have the following features: the ability to recognize and respond to verbal and nonverbal input; the ability to generate verbal and nonverbal output; the ability to deal with conversational functions such as turn taking, feedback, and repair mechanisms; and the ability to give signals that indicate the state of the conversation, as well as to contribute new propositions to the discourse. Cassell, “Conversation as a System Framework: Designing Embodied Conversational Agents,” incorporated herein by reference.
[0012] Massaro continues the work on conversation theory by developing Baldi, a computer animated talking head. When speaking, Baldi imitates the intonations and facial expressions of humans. Baldi has been used in language tutoring for children with hearing loss. Massaro, “Developing and Evaluating Conversational Agents,” Perpetual Science Laboratory, University of California. In later developments, Baldi was also given a body so as to allow for communicative gesturing and was taught to speak multiple languages. Massaro, “A Multilingual Embodied Conversational Agent,” University of California, Santa Cruz (2005), incorporated herein by reference.
[0013] Bickmore continues Cassell's work on embodied conversational agents. Bickmore finds that, in ECAs, the nonverbal channel is crucial for social dialogue because it is used to provide social cues, such as attentiveness, positive affect, and liking and attraction. Facial expressions also mark shifts into and out of social activities. Also, there are many gestures, e.g. waving one's hand to hail a taxi, crossing one's arms and shaking one's head to say “No,” etc. that are essentially communicative in nature and could serve as substitutes for words.
[0014] Bickmore further developed a computerized real estate agent, Rea, where, “Rea has a fully articulated graphical body, can sense the user passively through cameras and audio input, and is capable of speech with intonation, facial display, and gestural output. The system currently consists of a large projection screen on which Rea is displayed and which the user stands in front of. Two cameras mounted on top of the projection screen track the user's head and hand positions in space. Users wear a microphone for capturing speech input.” Bickmore & Cassell, “Social Dialogue with Embodied Conversational Agents,” incorporated herein by reference.
[0015] Similar to the work of Bickmore and Cassell, Beskow at the Royal Institute of Technology in Stockholm, Sweden created Olga, a conversational agent with gestures that is able to engage in conversations with users, interpret gestures, and make its own gestures. Beskow, “Olga—A Conversational Agent with Gestures,” Royal Institute of Technology, incorporated herein by reference.
[0016] In “Social Cues in Animated Conversational Agents,” Louwerse et al. note that people who interact with ECAs tend to react to them just as they do to real people. People tend to follow traditional social rules and to express their personality in usual ways in conversations with computer-based agents. Louwerse, M. M., Graesser, A. C., Lu, S., & Mitchell, H. H. (2005). Social cues in animated conversational agents. Applied Cognitive Psychology, 19, 1-12, incorporated herein by reference.
[0017] In another paper, Beskow further teaches how to model the dynamics of articulation for a parameterized talking head based on the phonetic input. Beskow creates four models of articulation (and the corresponding facial movements). To achieve this result, Beskow makes use of neural networks. Beskow further notes several uses of “talking heads.” These include virtual language tutors, embodied conversational agents in spoken dialogue systems, and talking computer game characters. In the computer game area, proper visual speech movements are essential for the realism of the characters. (This factor also causes “dubbed” foreign films to appear unrealistic.) Beskow, “Trainable Articulatory Control Models for Visual Speech Synthesis” (2004), incorporated herein by reference.
[0018] Ezzat goes even further, presenting a technique where a human subject is recorded uttering a predetermined speech corpus by a video camera. A visual speech model is created from this recording. Now, the computer can allow the person to make novel utterances and show how she would move her head while doing so. Ezzat creates a “multidimensional morpheme model” to synthesize new, previously unseen mouth configurations from a small set of mouth image prototypes.
[0019] In a similar field of endeavor, Picard proposes computer that can respond to user's emotions. Picard's ECAs can be used as an experimental emotional aid, as a pre-emptive tool to avert user frustration, and as an emotional skill-building mirror.
[0020] In the context of a customer call center, Bushey, U.S. Pat. No. 7,224,790, incorporated herein by reference, discusses conducting a “verbal style analysis” to determine a customer's level of frustration and the customer's goals in calling customer service. The “verbal style analysis” takes into account the number of words that the customer uses and the method of contact. Based in part on the verbal style analysis, customers are segregated into behavioral groups, and each behavioral group is treated differently by the customer service representatives. Gong, US App. 2003/0187660, incorporated herein by reference, goes further than Bushey, teaching an “intelligent social agent” that receives a plurality of physiological data and forms a hypothesis regarding the “affective state of the user” based on this data. Gong also analyzes vocal and verbal content and integrates the analysis to ascertain the user's physiological state.
[0021] Mood can be determined by various biometrics. For example, the tone of a voice or music is suggestive of the mood. See, Liu et al., Automatic Mood Detection from Acoustic Music Data, Johns Hopkins University Scholarship Library (2003). The mood can also be ascertained based on a person's statements. For example, if a person says, “I am angry,” then the person is most likely telling the truth. See Kent et al., Detection of Major and Minor Depression in Children and Adolescents, Journal of Child Psychology (2006). One's facial expression is another strong indicator of one's mood. See, e.g., Cloud, How to Lift Your Mood? Try Smiling Time Magazine (Jan. 16, 2009).
[0022] Therefore, it is feasible for a human user to convey his mood to a machine with an audio and a visual input by speaking to the machine, thereby allowing the machine to read his voice tone and words, and by looking at the machine, thereby allowing the machine to read his facial expressions.
[0023] It is also possible to change a person's mood through a conversational interface. For example, when people around one are smiling and laughing, one is more likely to forget one's worries and to smile and laugh oneself. In order to change a person's mood through a conversational interface, the machine implementing the interface must first determine the starting mood of the user. The machine would then go through a series of “optimal transitions” seeking to change the mood of the user. This might not be a direct transition. Various theories discuss how a person's mood might be changed by people or other external influences. For example, Neumann, “Mood Contagion”: The Automatic Transfer of Mood Between persons, Journal of Personality and Social Psychology (2000), suggests that if people around one are openly experiencing a certain mood, one is likely to join them in experiencing said mood. Other scholars suggest that logical mood mediation might be used to persuade someone to be happy. See, e.g., DeLongis, The Impact of Daily Stress on Health and Mood: Psychological and Social Resources as Mediators, Journal of Personality and Social Psychology (1988). Schwarz notes that mood can be impacted by presenting stimuli that were previously associated with certain moods, e.g. the presentation of chocolate makes one happy because one was previously happy when one had chocolate. Schwarz, Mood and Persuasion: Affective States Influence the Processing of Persuasive Communications, in Advances in Experimental Social Psychology, Vol. 24 (Academic Press 1991). Time
[0024] Magazine suggests that one can improve one's mood merely by smiling or changing one's facial expression to imitate the mood one wants to experience. Cloud, How to Lift Your Mood? Try Smiling. Time Magazine (Jan. 16, 2009).
[0025] Liquid crystal display (LCD) screens are known in the art as well. An LCD screen is a thin, flat electronic visual display that uses the light modulating properties of liquid crystals. These are used in cell phones, smartphones, laptops, desktops, and televisions. See Huang, U.S. Pat. No. 6,437,975, incorporated herein by reference, for a detailed discussion of LCD screen technology.
[0026] Many other displays are known in the art. For example, three-dimensional televisions and monitors are available from Samsung Corp. and Philips Corp. One embodiment of the operation of three-dimensional television, described by Imsand in U.S. Pat. No. 4,723,159, involves taking two cameras and applying mathematical transforms to combine the two received images of an object into a single image, which can be displayed to a viewer.
[0027] On its website, Samsung notes that it's three-dimensional televisions operate by “display[ing] two separate but overlapping images of the same scene simultaneously, and at slightly different angles as well.” One of the images is intended to be perceived by the viewer's left eye. The other is intended to be perceived by the right eye. The human brain should convert the combination of the views into a three-dimensional image. See, generally, Samsung 3D Learning Resource, www.samsung.com/us/learningresources3D (last accessed May 10, 2010).
[0028] Projectors are also known in the art. These devices project an image from one screen to another. Thus, for example, a small image on a cellular phone screen that is difficult for an elderly person to perceive may be displayed as a larger image on a wall by connecting the cell phone with a projector. Similarly, a netbook with a small screen may be connected by a cable to a large plasma television or plasma screen. This would allow the images from the netbook to be displayed on the plasma display device.
[0029] Devices for forming alternative facial expressions are known in the art. There are many children's toys and pictures with changeable facial expressions. For example, Freynet, U.S. Pat. No. 6,146,721, incorporated herein by reference, teaches a toy having alternative facial expression. An image of a face stored on a computer can be similarly presented on an LCD screen with a modified facial expression. See also U.S. Pat. No. 5,215,493, U.S. Pat. No. 5,902,169, U.S. Pat. No. 3,494,068, and U.S. Pat. No. 6,758,717, expressly incorporated herein by reference.
[0030] In addition, emergency detection systems taking input from cameras and microphones are known in the art. These systems are programmed to detect whether an emergency is ongoing and to immediately notify the relevant parties (e.g. police, ambulance, hospital or nursing home staff, etc.). One such emergency detection system is described by Lee, U.S. Pat. No. 6,456,695, expressly incorporated herein by reference. Lee suggests that an emergency call could be made when an emergency is detected, but does not explain how an automatic emergency detection would take place. However, Kirkor, U.S. Pat. No. 4,319,229, proposes a fire emergency detector comprising “three separate and diverse sensors . . . a heat detector, a smoke detector, and an infrared radiation detector.” Under Kirkor's invention, when a fire emergency is detected, (through the combination of inputs to the sensors) alarm is sounded to alert individuals in the building and the local fire department is notified via PSTN. In addition, some modern devices, for example, the Emfit Movement Monitor/Nighttime Motion Detection System, www.gosouthernmd.com/store/store/comersus_viewItem.asp?idProduct=35511, last accessed May 10, 2010, comprise a camera and a pressure sensor adapted to watch a sleeping person and to alert a caregiver when the sleeping patient is exhibiting unusual movements.
[0031] See, also (each of which is expressly incorporated herein by reference):
[0032] Andre, et al., “Employing AI Methods to Control the Behavior of Animated Interface Agents.”
[0033] Andre, et al., “The Automated Design of Believable Dialogues for Animated Presentation Teams”; in J. Cassell, S. Prevost, J. Sullivan, and E. Churchill: Embodied Conversational Agents, The MIT Press, pp. 220-255, 2000.
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SUMMARY OF THE INVENTION
[0115] The present system and method provide a conversational interactive interface for an electronic system, which communicates using traditional human communication paradigms, and employs artificial intelligence to respond to the user. Many of technologies employed by components of the system and method are available. For example, by combining the technologies of, Gupta U.S. Pat. No. 6,138,095 (word recognizer), Bohacek U.S. Pat. No. 6,411,687 (mood detector based on speech), Black U.S. Pat. No. 5,774,591 (facial expression to mood converter), and Bushey U.S. Pat. No. 7,224,790 (analysis of word use to detect the attitude of the customer), the mood of a user of a computer with a camera and a microphone who is looking into the camera and speaking into the microphone can effectively be ascertained.
[0116] Conversation is a progression of exchanges (usually oral, but occasionally written) by participants. Each participant is a “learning system,” that is, a system that is adaptive and changes internally as a consequence of experience. This highly complex type of interaction is also quite powerful, for conversation is the means by which existing knowledge is conveyed, and new knowledge is generated. Conversation is different from other interactions, such as a mechanical response (e.g. door that opens when one presses a button or an Internet search query that returns a pre-determinable set of results) because conversation is not a simple reactive system. It is a uniquely personal interaction to the degree that any output response must be based on the input prior statement, as well as other information about one's dealings with the other party to the conversation and former conversation. It often involves synthesis of ideas with new information or preexisting information not previously expressed for the purpose at hand, and can also involve a form of debate, where a party adopts a position or hypothesis that it does not hold firmly, in order to continue the interaction. As a result, the thesis or topic can itself evolve, since the conversation need not be purposeful. Indeed, for social conversation, the process is not intended to resolve or convince, but rather to entertain.
[0117] One would normally converse very differently with one's spouse, one's child, one's social friend, and one's business colleague, thus making conversation dependent on the counterparty. See, generally, Gordon Pask, Conversation Theory, Applications in Education and Epistemology, Elsevier, 1976; Gordon Pask, Heinz von Foerster's Self-Organisation, the Progenitor of Conversation and Interaction Theories, 1996. We say that an output response is “conversationally relevant” to an input prior statement and course of dealings if the output builds on the input, and does more than merely repeats the information that can be found in the prior course of dealings. Often, the evolution of a conversation incorporates “new” facts, such as current events or changes from a prior conversation.
[0118] In spite of a large amount of technology created for the care of elderly people, a problem which many elderly people experience is loneliness. Many elderly individuals live alone or in nursing homes and do not have as much company as they would like due to the fact that many of their friends and families are far away, unavailable, sick or deceased. In addition, a large percentage of elderly people do not drive and have difficulty walking, making it difficult for them to transport themselves to visit their friends. Social and business networking websites, such as Facebook and LinkedIn, which are popular among younger generations, are not as popular with elderly people, creating a need in the elderly community for updates regarding their friends and families One particular issue is a generation gap in technological proficiency, and comfort level with new types of man-machine interfaces. For example, older generations are more comfortable using a telephone than a computer for communications, and may also prefer “face to face” conversation to voice only paradigms.
[0119] The present invention provides, according to one aspect, an automated device that allows humans, and especially elderly people, to engage in conversational interactions, when they are alone. Such automated devices may provide users with entertainment and relevant information about the world around them. Also, preferably, this device would contribute to the safety of the elderly people by using the camera and microphone to monitor the surroundings for emergency situations, and notify the appropriate people if an emergency takes place.
[0120] A preferred embodiment of the invention provides a personal interface device. The personal interface device is, for example, particularly adapted for use by an elderly or lonely person in need of social interaction.
[0121] In a first embodiment, the personal interface device has a microphone adapted to receive audio input, and a camera adapted to receive image input. Persons having ordinary skill in the art will recognize many such devices that have a microphone and a camera and could be used to implement this invention. For example, the invention could be implemented on a cell phone, a smartphone, such as a Blackberry or Apple iPhone, a PDA, such as an Apple iPad, Apple iPod or Amazon Kindle, a laptop computer, a desktop computer, or a special purpose computing machine designed solely to implement this invention. Preferably, the interface device comprises a single integral housing, such as a cellular telephone, adapted for video conferencing, in which both a video camera and image display face the user.
[0122] In a preferred embodiment, the device is responsive to voice commands, for example supporting natural language interaction. This embodiment is preferred because many elderly people have difficulty operating the small buttons on a typical keyboard or cell phone. Thus the oral interaction features, for both communication and command and control, are helpful.
[0123] Embodiments of the invention further comprise at least one processor executing software adapted to determine the mood of the user based on at least one of the audio input and the image input. This mood determination could take into account many factors. In addition to the actual words spoken by the user, the mood might be inferred from the content of the conversation, user's tone, hand gestures, and facial expressions. The mood could be ascertained, for example, through an express input, a rule-based or logical system, through a trainable neural network, or other known means. For example, a user mood may be determined in a system according to an embodiment of the present invention which combines and together analyzes data derived from application of the technologies of Gupta (U.S. Pat. No. 6,138,095), which provides a word recognizer, Bohacek (U.S. Pat. No. 6,411,687), which provides a mood detector based on speech, Black (U.S. Pat. No. 5,774,591), which provides a system and method to ascertain mood based on facial expression, and Bushey (U.S. Pat. No. 7,224,790), which analyzes word use to detect the attitude of the customer.
[0124] In one embodiment, in order to have conversations that are interesting to the user, the device is adapted to receive information of interest to the user from at least one database or network, which is typically remote from the device, but may also include a local database and/or cache, and which may also be provided over a wireless or wired network, which may comprise a local area network, a wide area network, the Internet, or some combination. Information that is of interest to the user can also be gathered from many sources. For example, if the user is interested in finance, the device could receive information from Yahoo Finance and the Wall Street Journal. If the user is interested in sports, the device could automatically upload the latest scores and keep track of ongoing games to be able to discuss with the user. Also, many elderly people are interested in their families, but rarely communicate with them. The device might therefore also gather information about the family through social networking websites, such as Facebook and LinkedIn. Optionally, the device might also track newspaper or other news stories about family members. In one embodiment, artificial intelligence techniques may be applied to make sure that the news story is likely to be about the family member and not about someone with the same name. For example, if a grandson recently graduated from law school, it is likely that the grandson passed the local Bar Exam, but unlikely that the grandson committed an armed robbery on the other side of the country. In another embodiment, the device could notify the user when an interesting item of information is received, or indeed raise this as part of the “conversation” which is supported by other aspects of the system and method. Therefore, the device could proactively initiate a conversation with the user under such a circumstance, or respond in a contextually appropriate manner to convey the new information. A preferred embodiment of this feature would ensure that the user was present and available to talk before offering to initiate a conversation. Thus, for example, if there were other people present already engaged in conversation (as determined by the audio information input and/or image information input), an interruption might be both unwarranted and unwelcome.
[0125] The gathering of information might be done electronically, by an automatic search, RSS (most commonly expanded as “Really Simple Syndication” but sometimes “Rich Site Summary”) feed, or similar technique. The automatic information gathering could take place without a prompt or other action from the user. Alternatively, in one embodiment, the device communicates with a remote entity, (e.g. call center employee) who may be someone other than the user-selected person who is displayed on the screen, that communicates information in response to the requests of the user. In one embodiment, the remote entity is a human being who is responsible for keeping the conversation interesting for the user and for ensuring the truth and veracity of the information being provided. This embodiment is useful because it ensures that a software bug would not report something that is upsetting or hurtful to the user.
[0126] In various embodiments, the device has a display. The display may, for example, present an image of a face of a person. The person could be, for example, anyone of whom a photograph or image is available, or even a synthetic person (avatar). It could be a spouse, a relative, or a friend who is living or dead. The image is preferably animated in an anthropomorphically accurate manner, thus producing an anthropomorphic interface. The interface may adopt mannerisms from the person depicted, or the mood and presentation may be completely synthetic.
[0127] The device preferably also has at least one speaker. The speaker is adapted to speak in a voice associated with the gender of the person on the display. In one embodiment, the voice could also be associated with the race, age, accent, profession, and background of the person in the display. In one embodiment, if samples of the person's voice and speech are available, the device could be programmed to imitate the voice.
[0128] Also, the invention features at least one programmable processor that is programmed with computer executable code, stored in a non-transitory computer-readable medium such as flash memory or magnetic media, which when executed is adapted to respond to the user's oral requests with at least audio output that is conversationally relevant to the audio input. As noted above, the audio output is preferably in the voice of the person whose image appears on the display, and both of these may be user selected. In one embodiment, the processor stores information of interest to the user locally, and is able to respond to the user's queries quickly, even if remote communication is unavailable. For example, a user might ask about a score in the recent Yankees game. Because the device “knows” (from previous conversations) that the user is a Yankees fan, the processor will have already uploaded the information and is able to report it to the user. In another embodiment, the device is connected to a remote system, such as a call center, where the employees look up information in response to user requests. Under this “concierge” embodiment, the device does not need to predict the conversation topics, and the accuracy of the information provided is verified by a human being.
[0129] In a preferred embodiment, the processor implementing the invention is further adapted to receive input from the microphone and/or the camera and to process the input to determine the existence of an emergency. The emergency could be detected either based on a rule-based (logical) system or based on a neural network trained by detecting various emergency scenarios. If an emergency is detected, the processor might inform an emergency assistance services center which is contact, for example, through a cellular telephone network (e.g., e911), cellular data network, the Internet, or produce a local audio and/or visual alert.
[0130] Emergency assistance services may include, for example, police, fire, ambulance, nursing home staff, hospital staff, and/or family members. The device could be further adapted to provide information about the emergency to emergency assistance personnel. For example, the device could store a video recording of events taking place immediately before the accident, and/or communicate live audio and/or video.
[0131] Another embodiment of the invention is directed to a machine-implemented method of engaging in a conversation with a user. In the first step, the machine receives audio and visual input from the user. Such input could come from a microphone and camera connected to the machine. Next, the machine determines the mood of the user based on at least one of the audio input and the visual input. To do this, the machine considers features including facial expressions and gestures, hand gestures, voice tone, etc. In the following step, the machine presents to the user a face of a user-selected person or another image, wherein the facial expression of the person depends on, or is responsive to, the user's mood. The person could be anyone of whom a photograph is available, for example, a dead spouse or friend or relative with whom the user wishes that she were speaking. Alternatively, the user-selected person could be a famous individual, such as the President. If the user does not select a person, a default will be provided. The device may develop its own “personality” based on a starting state, and the various interactions with the user.
[0132] In a preferred embodiment, the machine receives information of interest to a user from a database or network. For example, if a user is interested in weather, the machine might upload weather data to be able to “discuss” the weather intelligently. If the user is interested in college football, the machine might follow recent games and “learn” about key plays. In one embodiment, the current conversation could also be taken into account in determining the information that is relevant to the machine's data mining.
[0133] Finally, the last step involves providing audio output in a voice associated with a gender of the user-selected person, the tone of the voice being dependent on at least the mood of the user, wherein the audio output is conversationally relevant to the audio input from the user.
[0134] In an embodiment of the invention where the machine initiates a conversation with the user, the first step is to receive information of interest from at least one database or network, such as the Internet. The next step is to request to initiate a conversation with the user. Optionally, the machine could check that the user is present and available before offering to initiate a conversation. The machine would then receive from the user an audio input (words spoken into a microphone) and visual input (the user would look on the screen and into a camera). The user would then be presented with an image of the person he selected to view on the screen. The facial expression on the person would be dependent on the mood of the user. In one embodiment the machine would either imitate the mood of the user or try to cheer up the user and improve his mood. Finally, the machine would provide audio output in a voice associated with the gender of the user-selected person on the screen. The tone of the voice will be dependent on the mood of the user. The audio output will be conversationally relevant to the audio input from the user.
[0135] Persons skilled in the art will recognize many forms of hardware which could implement this invention. For example, a user interface system may be provided by an HP Pavilion dv4t laptop computer, which has a microphone, video camera, display screen, speakers, processor, and wireless local area network communications, with capacity for Bluetooth communication to a headset and wide area networking (cellular data connection), and thus features key elements of various embodiments of the invention in the body of the computer. If the laptop or desktop computer does not have any of these features, an external screen, webcam, microphone, and speakers could be used. Alternatively, aspects of the invention could be implemented on a smartphone, such as the Apple iPhone or a Google//Motorola Android “Droid.” However, an inconvenience in these devices is that the camera usually faces away from the user, such that the user cannot simultaneously look at the screen and into the camera. This problem can be remedied by connecting an iPhone 3G with an external camera or screen or by positioning mirrors such that the user can see the screen while the camera is facing a reflection of the user.
[0136] Almost any modern operating system can be used to implement this invention. For example, one embodiment can run on Windows 7. Another embodiment can run on Linux. Yet another embodiment can be implemented on Apple Mac Os X. Also, an embodiment can be run as an Apple iPhone App, a Windows Mobile 6.5 or 7.0 App, a RIM Blackberry App, an Android App or a Palm App. The system need not be implemented as a single application, except on systems which limit multitasking, e.g., Apple iPhone, and therefore may be provided as a set of cooperating software modules. The advantage of a modular architecture, especially with an open application programming interface, is that it allows replacement and/or upgrade of different modules without replacing the entire suite of software. Likewise, this permits competition between providers for the best module, operating within a common infrastructure.
[0137] Thus, for example, the conversation logic provided to synthesize past communications and external data sources may be designed in different ways. Rather than mandating a single system, this module may be competitively provided from different providers, such as Google, Microsoft, Yahoo!, or other providers with proprietary databases and/or algorithms Likewise, in some cases, a commercial subsidy may be available from a sponsor or advertiser for display or discussion of its products, presumably within the context of the conversation. Thus, for example, if the subject of “vacation” is raised, the agent within the device might respond by discussing a sponsor's vacation offering. The user might say: “I hate sitting here-I want to go on vacation somewhere fun!”. The device, recognizing the word “vacation” in the context of an open-ended declarative, might respond: “early summer is a great time to go to Florida, before the hurricane season. Hilton Hotels are having a timeshare promotion like the one you went on last year. You can invite grandson Jimmy, who did well in school this year.” The user may respond: “that's a great idea. How much does it cost? And I don't want to sit in an endless timeshare sales pitch!” The device might then respond: “If you sit in the sales pitch, which is 90 minutes, you get $300 off the hotel rate, plus it keeps you out of the sun midday. Besides, your friend Wendy Montclair owns a timeshare there and wrote goods things about it on her blog. You always liked Wendy.” The user might respond: “I don't like her anymore. She's going out with Snidely Whiplash!” The device might then respond, “You're joking. Snidely Whiplash is a cartoon character from Dudley Do-Right. Besides, the timeshare you now own went up in value, and you can sell it at a profit to buy this one.” The user might respond, “I bought the last one to be near Harry. He's a good friend.” The conversational interface might respond: “I just checked; Harry Lefkowitz passed away last month at age 79. His obituary is in the Times. Would you like me to read it to you?”
[0138] As can be seen from this exchange, the conversational interface seeks to synthesize information, some of which can be gathered in real time based on the context of the conversation, and may optionally have commercial motivation. This motivation or biasing is generally not too strong, since that might undermine the conversational value of the device, but the commercial biasing might be used to reduce the acquisition and/or usage costs of the device, and adaptively provide useful information to the user.
[0139] In another embodiment, ads and incentives may be brokered in real time by a remote database. That is, there is no predetermined commercial biasing, but after the user interacts with the device to trigger a “search,” a commercial response may be provided, perhaps accompanied by “organic” responses, which can then be presented to the user or synthesized into the conversation. For example, the remote system may have “ads” that are specifically generated for this system and are communicated with sophisticated logic and perhaps images or voices. An example of this is a T-Mobile ad presented conversationally by a Catherine Zeta Jones avatar, talking with the user about the service and products, using her voice and likeness. Assuming the user is a fan, this “personalized” communication may be welcomed, in place of the normal images and voices of the interface. Special rules may be provided regarding what information is uploaded from the device to a remote network, in order to preserve privacy, but in general, an ad-hoc persona provided to the device may inherit the knowledge base and user profile database of the system. Indeed, this paradigm may form a new type of “website,” in which the information is conveyed conversationally, and not as a set of static or database-driven visual or audio-visual depictions.
[0140] Yet another embodiment does not require the use of a laptop or desktop computer. Instead, the user could dial a phone number from a home, office, or cellular phone and turn on television to a prearranged channel. The television would preferably be connected to the cable or telephone company's network, such that the cable or telephone company would know which video output to provide. The telephone would be used to obtain audio input from the user. Note that video input from the user is not provided here.
[0141] The software for running this app could be programmed in almost any programming language, such as Java or C++. Microphones, speakers, and video cameras typically have drivers for providing input or output. Also, Skype provides a video calling platform. This technology requires receiving video and audio input from a user. Skype can be modified such that, instead of calling a second user, a user would “call” an avatar implementing the present invention, which would apply the words the user speaks, as well as the audio and video input provided from the user by the Skype software in order to make conversationally relevant responses to the user.
[0142] It is therefore an object to provide a method, and system for performing the method comprising: receiving audio-visual information; determining at least one of a topic of interest to a user and a query by a user, dependent on received audio-visual information; presenting an anthropomorphic object through an audio-visual output controlled by at least one automated processor, conveying information of interest to the user, dependent on at least one of the determined topic of interest and the query; and telecommunicating audio-visual information through a telecommunication interface. The anthropomorphic object may have an associated anthropomorphic mood which is selectively varied in dependence on at least one of the audio-visual information input, the topic of interest, and the received information.
[0143] The receiving, presenting and telecommunicating may be performed using a self-contained cellular telephone communication device. The system may respond to spoken commands. The system may determine an existence of an emergency condition. The system may automatically telecommunicate information about the emergency condition without required human intervention. The emergency condition may be automatically telecommunicated with a responder selected from one or more of the group consisting police, fire, and emergency medical. The query or topic of interest may be automatically derived from the audio-visual information input and communicated remotely from the device through the Internet. The system may automatically interact with a social networking website and/or an Internet search engine and/or a call center through the telecommunication interface. The system may respond to the social networking website, Internet search engine, or call center by transmitting audio-visual information. The system may automatically receive at least one unit of information of interest to the user from a resource remote from the device substantially without requiring an express request from the user, and may further proactively interact with the user in response to receiving said at least one unit of information. The anthropomorphic object may be modified to emulate a received image of a person. The audio-visual output may be configured to emulate a voice corresponding to characteristics of the person represented in the received image of the person. The system may present at least one advertisement responsive to at least one of the topic of interest and the query, and financially accounting for at least one of a presentation of the at least one advertisement and a user interaction with the at least one advertisement. The system may generate structured light, and capture three-dimensional information based at least on the generated structured light. The system may capture a user gesture, and control the anthropomorphic object in dependence on the user gesture. The system may automatically generate a user profile generated based on at least prior interaction with the user.
[0144] It is a further object to provide a user interface device, and method of use, comprising: an audio-visual information input configured to receive information sufficient to determine at least one of a topic of interest to a user and a query by a user, dependent on received audio-visual information; at least one audio-visual output configured to present an anthropomorphic object controlled by at least one automated processor, conveying information of interest to the user, dependent on at least one of the determined topic of interest and the query; and an audio-visual telecommunication interface. The at least one automated processor may control the anthropomorphic object to have an associated anthropomorphic mood which is selectively varied in dependence on at least one of the audio-visual information input, the topic of interest, and the received information.
[0145] The audio-visual information input and audio-visual output may be implemented on a self-contained cellular telephone communication device. The at least one automated processor may be configured to respond to spoken commands, and to process the received information and to determine an emergency condition. The at least one processor may be configured to automatically telecommunicate information about the determined emergency condition without required human intervention. The determined emergency condition may be automatically telecommunicated with a responder selected from one or more of the group consisting police, fire, and emergency medical. The system may automatically interact with a social networking website based on at least an implicit user command may be provided. The system may be configured to automatically interact with a call center, and to automatically respond to the call center to transmit audio-visual information may be provided. The at least one processor may be configured to automatically receive at least one unit of information of interest to the user from a resource remote from the device substantially without requiring an express request from the user and to initiate an interaction with the user in response to receiving said at least one unit of information. The anthropomorphic object may be configured to represent a received image of a person and to provide an audio output in a voice corresponding to a characteristic of the received image of the person. The at least one processor may be configured to present at least one advertisement responsive to at least one of the topic of interest and the query and to permit the user to interact with the advertisement. The audio-visual information input may comprise a structured light image capture device. The at least one processor may be configured to automatically generate a user profile generated based on the at least prior interaction of the user. The mood may correspond to a human emotional state, and the at least one processor may be configured to determine a user emotional state based on at least the audio-visual information.
[0146] It is a further object to provide a method comprising: defining an automated interactive interface having an anthropomorphic personality characteristic, for semantically interacting with a human user to receive user input and present information in a conversational style; determining at least one of a topic of interest to a user dependent on the received user input; automatically generating a query seeking information corresponding to the topic of interest from a database; receiving information of interest to the user from the database, comprising at least a set of facts or information; and providing at least a portion of the received facts or information to the user through the automated interactive interface, in accordance with the conversational style, responsive to the received user input, and the information of interest. The conversational style may be defined by a set of conversational logic comprising at least a persistent portion and an information of interest responsive portion. The anthropomorphic personality characteristic may comprise an automatically controlled human emotional state, the human emotional state being controlled responsive to at least the received user input. Telecommunications with the database may be conducted through a wireless network interface.
[0147] It is another object to provide a user interface system comprising an interactive interface; and at least one automated processor configured to control the interactive interface to provide an anthropomorphic personality characteristic, configured to semantically interact with a human user to receive user input and present information in a conversational style; determine at least one of a topic of interest to a user dependent on the received user input; automatically generate a query seeking information corresponding to the topic of interest from a database; receive information of interest to the user from the database, comprising at least a set of facts or information; and provide at least a portion of the received facts or information to the user through the interactive interface, in accordance with the conversational style, responsive to the received user input, and the information of interest. The conversational style may be defined by a set of conversational logic comprising at least a persistent portion and an information of interest responsive portion. The anthropomorphic personality characteristic may comprise a human emotional state, the human emotional state being controlled responsive to at least the received user input. A wireless network interface telecommunications port may be provided, configured to communicate with the database.
[0148] Another object provides a method comprising: defining an automated interactive interface having an artificial intelligence-based anthropomorphic personality, configured to semantically interact with a human user through an audio-visual interface, to receive user input and present information in a conversational style; determining at least one of a topic of interest to a user dependent on at least the received user input and a history of interaction with the user; automatically generating a query seeking information corresponding to the topic of interest from a remote database through a telecommunication port; receiving information of interest to the user from the remote database through the telecommunication port, comprising at least a set of facts or information; and controlling the automated interactive interface to convey the facts or information to the user in the conversation style, subject to user interruption and modification of the topic of interest.
[0149] A still further object provides a system, comprising: a user interface, comprising a video output port, an audio output port, a camera, a structured lighting generator, and an audio input port; a telecommunication interface, configured to communicate at least a voice conversation through an Internet interface; and at least one processor, configured to receive user input from the user interface, to generate signals for presentation through the user interface, and to control the telecommunication interface, the at least one processor being responsive to at least one user gesture captured by the camera in conjunction with the structured lighting generator to provide control commands for voice conversation communication.
[0150] Another object provides a system and method for presenting information to a user, comprising: generating a data file corresponding to a topic of information, the data file comprising facts and conversational logic; communicating the data file to a conversational processor system, having a human user interface configured to communicate a conversational semantic dialog with a user; processing the data file in conjunction with a past state of the conversational semantic dialog with the conversational processor; outputting through the human user interface a first semantic construct in dependence on at least the data file; receiving, after outputting said first semantic construct, through the human user interface a semantic user input; and outputting, after receiving said semantic user input, through the human user interface, a conversationally appropriate second semantic construct in dependence on at least the data file and said semantic user input. The method may further comprise receiving a second data file comprising at least one additional fact, after said receiving said semantic user input, wherein said conversationally appropriate second semantic construct is generated in dependence on at least the second data file.
[0151] These and other objects will become apparent from a review of the preferred embodiments and figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0152] FIG. 1 illustrates an exemplary machine implementing an embodiment of the present invention.
[0153] FIG. 2 illustrates a flowchart of a method implementing an embodiment of the present invention.
[0154] FIG. 3 illustrates an embodiment of this invention which can be run on a substantially arbitrary cell phone with low processing abilities.
[0155] FIG. 4 illustrates a flowchart for a processor implementing an embodiment of the present invention.
[0156] FIG. 5 illustrates a smart clock radio implementing an embodiment of the present invention.
[0157] FIG. 6 illustrates a television with a set-top box implementing an embodiment of the present invention.
[0158] FIG. 7 illustrates a special purpose robot implementing an embodiment of the present invention.
[0159] FIG. 8 shows a prior art computer system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
EXAMPLE 1
Cell Phone
[0160] FIG. 1 illustrates an exemplary machine 100 that can be used to implement an embodiment of the present invention. The machine comprises a microphone 110 adapted to receive audio information input and a camera 120 adapted to receive image information input. The camera 120 is preferably is facing the user. There are one or more speakers 130 for audio output (e.g., voice reproduction) and a display 140 , which also preferably faces the user. There is also a processor (not illustrated in FIG. 1 , but an exemplary processor appears in FIG. 4 ) and the machine is preferably at least sometimes able to connect to the Internet or a remote database server which stores a variety of human-interest information. The image 150 in display 140 is preferably the face of a person who is selected by the user. The face may also be of another species, or completely synthetic. In one embodiment, the lips of image 150 move as image 150 speaks, and image 150 's facial expression is determined to convey an anthropomorphic mood, which itself may be responsive to the mood of the user, as signaled by the audio and image input through microphone 110 and camera 120 . The mood of the user may be determined from the words spoken by the user, the voice tone of the user, the facial expression and gestures of the user, the hand gestures of the user, etc. The device 100 may be configured as a cellular telephone or so-called smartphone, but persons having ordinary skill in the art will realize that this invention could be implemented in many other form factors and configurations. For example, the device could be run on a cell phone, a smart phone (e.g. Blackberry, Apple iPhone), a PDA (e.g. Apple iPod, Apple iPad, Amazon Kindle), a laptop computer, a desktop computer, or a special purpose computing machine, with relatively minor modifications. The interface may be used for various consumer electronics devices, such as automobiles, televisions, set-top boxes, stereo equipment, kitchen appliances, thermostats and HVAC equipment, laundry appliances, and the like. The interface may be employed in public venues, such as vending machines and ATMs. In some cases, the interface may be an audio-only interface, in which imaging may be unidirectional or absent. In audio-only systems, the interface seeks to conduct an intelligent conversational dialog and may be part of a call center or interactive voice response system. Thus, for example, the technology might be employed to make waiting queues for call centers more interesting and tolerable for users.
[0161] FIG. 2 is a flowchart 200 illustrating the operation of one embodiment of the invention. In step 210 , the user Ulysses looks into the camera and speaks into the microphone. Preferably, the user would naturally be looking into the camera because it is located near the screen where an image of a person is displayed. The person could be anyone whom the user selects, of whom the user can provide a photograph. For example, it might be a deceased friend or spouse, or a friend or relative who lives far away and visits rarely. Alternatively, the image might be of a famous person. In the example, the image in the machine (not illustrated) is of Ulysses' wife, Penelope.
[0162] In the example, in step 210 , Ulysses says, “Is my grandson James partying instead of studying?” Ulysses has an angry voice and a mad facial expression. In step 220 , the machine detects the mood of the user (angry/mad) based on audio input (angry voice) and image input (mad facial expression). This detection is done by one or more processors, which is, for example, a Qualcomm Snapdragon processor. Also, the one or more processors are involved in detecting the meaning of the speech, such that the machine would be able to provide a conversationally relevant response that is at least partially responsive to any query or comment the user makes, and builds on the user's last statement, in the context of this conversation and the course of dealings between the machine and the user. Roy, US App. 2009/0063147, incorporated herein by reference, discusses an exemplary phonetic, syntactic and conceptual analysis drive speech recognition system. Roy's system, or a similar technology, could be used to map the words and grammatical structures uttered by the user to a “meaning”, which could then be responded to, with a response converted back to speech, presented in conjunction with an anthropomorphic avatar on the screen, in order to provide a conversationally relevant output. Another embodiment of this invention might use hierarchal stacked neural networks, such as those described by Commons, U.S. Pat. No. 7,613,663, incorporated herein by reference, in order to detect the phonemes the user pronounces and to convert those phonemes into meaningful words and sentence or other grammatical structures. In one embodiment, the facial expression and/or the intonation of the user's voice are coupled with the words chosen by the user to generate the meaning. In any case, at a high level, the device may interpret the user input as a concept with a purpose, and generates a response as a related concept with a counter-purpose. The purpose need not be broader than furthering the conversation, or it may be goal-oriented. In step 230 , the machine then adjusts the facial expression of the image of Penelope to angry/mad to mirror the user, as a contextually appropriate emotive response. In another embodiment, the machine might use a different facial expression in order to attempt to modify the user's mood. Thus, if the machine determines that a heated argument is an appropriate path, then a similar emotion to that of the user would carry the conversation forward. In other cases, the interface adopts a more submissive response, to defuse the aggression of the user.
[0163] Clearly, the machine has no way of knowing whether James is partying or studying without relying on external data. However, according to one embodiment of the invention, the machine can access a network, such as the Internet, or a database to get some relevant information. Here, in step 240 , the machine checks the social networking website Facebook to determine James' recent activity. Facebook reveals that James got a C on his biology midterm and displays several photographs of James getting drunk and engaging in “partying” behavior. The machine then replies 250 to the user, in an angry female voice, “It is horrible. James got a C on his biology midterm, and he is drinking very heavily. Look at these photographs taken by his neighbor.” The machine then proceeds to display the photographs to the user. In step 260 , the user continues the conversation, “Oh my God. What will we do? Should I tell James that I will disinherit him unless he improves his grades?”
[0164] Note that a female voice was used because Penelope is a woman. In one embodiment, other features of Penelope, for example, her race, age, accent, profession, and background could be used to select an optimal voice, dialect, and intonation for her. For example, Penelope might be a 75-year-old, lifelong white Texan housewife who speaks with a strong rural Texas accent.
[0165] The machine could look up the information about James in response to the query, as illustrated here. In another embodiment, the machine could know that the user has some favorite topics that he likes to discuss (e g family, weather, etc.) The machine would then prepare for these discussions in advance or in real-time by looking up relevant information on the network and storing it. This way, the machine would be able to discuss James' college experience in a place where there was no Internet access. In accordance with this embodiment, at least one Internet search may occur automatically, without a direct request from the user. In yet another embodiment, instead of doing the lookup electronically, the machine could connect to a remote computer server or a remote person who would select a response to give the user. Note that the remote person might be different from the person whose photograph appears on the display. This embodiment is useful because it ensures that the machine will not advise the user to do something rash, such as disinheriting his grandson.
[0166] Note that both the machine's response to the user's first inquiry and the user's response to the machine are conversationally relevant, meaning that the statements respond to the queries, add to the conversation, and increase the knowledge available to the other party. In the first step, the user asked a question about what James was doing. The machine then responded that James' grades were bad and that he had been drunk on several occasions. This information added to the user's base of knowledge about James. The user then built on what the machine had to say by suggesting threatening to disinherit James as a potential solution to the problem of James' poor grades.
[0167] In one embodiment, the machine starts up and shuts down in response to the user's oral commands. This is convenient for elderly users who may have difficulty pressing buttons. A deactivation permits the machine to enter into a power saving low power consumption mode. In another embodiment, the microphone and camera monitor continuously the scene for the presence of an emergency. If an emergency is detected, emergency assistance services, selected for example from the group of one or more of police, fire, ambulance, nursing home staff, hospital staff, and family members might be called. Optionally, the device could store and provide information relevant to the emergency, to emergency assistance personnel. Information relevant to the emergency includes, for example, a video, photograph or audio recording of the circumstance causing the emergency. To the extent the machine is a telephone, an automated e911 call might be placed, which typically conveys the user's location. The machine, therefore, may include a GPS receiver, other satellite geolocation receiver, or be usable with a network-based location system.
[0168] In another embodiment of this invention, the machine provides a social networking site by providing the responses of various people to different situations. For example, Ulysses is not the first grandfather to deal with a grandson with poor grades who drinks and parties a lot. If the machine could provide Ulysses with information about how other grandparents dealt with this problem (without disinheriting their grandchildren), it might be useful to Ulysses.
[0169] In yet another embodiment (not illustrated) the machine implementing the invention could be programmed to periodically start conversations with the user itself, for example, if the machine learns of an event that would be interesting to the user. (E.g., in the above example, if James received an A+ in chemistry, the machine might be prompted to share the happy news with Ulysses.) To implement this embodiment, the machine would receive relevant information from a network or database, for example through a web crawler or an RSS feed. Alternatively, the machine could check various relevant websites, such as James' social networking pages, itself to determine if there are updates. The machine might also receive proactive communications from a remote system, such as using an SMS or MMS message, email, IP packet, or other electronic communication.
EXAMPLE 2
Cell Phone with Low Processing Abilities
[0170] This embodiment of this invention, as illustrated in FIG. 3 , can be run on an arbitrary cell phone 310 connected to a cellular network, such as the GSM and CDMA networks available in the US, such as the Motorola Razr or Sony Ericsson W580. The cell phone implementing this embodiment of the invention preferably has an ability to place calls, a camera, a speakerphone, and a color screen. To use the invention, the user of the cell phone 310 places a call to a call center 330 . The call could be placed by dialing a telephone number or by running an application on the phone. The call is carried over cell tower 320 . In response to placing the call, an image of a person selected by the user or an avatar appears on the screen of the cell phone 310 . Preferably, the call center is operated by the telephone company that provides cell phone service for cell phone 310 . This way, the telephone company has control over the output on the screen of the cell phone as well as over the voice messages that are transmitted over the network.
[0171] The user says something that is heard at call center 330 by employee 332 . The employee 332 can also see the user through the camera in the user's telephone. An image of the user appears on the employee's computer 334 , such that the employee can look at the user and infer the user's mood. The employee then selects a conversationally relevant response, which builds on what the user said and is at least partially responsive to the query, to say to the user. The employee can control the facial expression of the avatar on the user's cell phone screen. In one embodiment, the employee sets up the facial expression on the computer screen by adjusting the face through mouse “drag and drop” techniques. In another embodiment, the computer 334 has a camera that detects the employee's facial expression and makes the same expression on the user's screen. This is processed by the call center computer 334 to provide an output to the user through cell phone's 310 speaker. If the user asks a question, such as, “What will the weather be in New York tomorrow?” the call center employee 332 can look up the answer through Google or Microsoft Bing search on computer 334 .
[0172] Preferably, each call center employee is assigned to a small group of users whose calls she answers. This way, the call center employee can come to personally know the people with whom she speaks and the topic that they enjoy discussing. Conversations will thus be more meaningful to the users.
EXAMPLE 3
Smart Phone, Laptop or Desktop with CPU Connected to a Network
[0173] Another embodiment of the invention illustrated in FIG. 4 , is implemented on a smartphone, laptop computer, or desktop computer with a CPU connected to a network, such as a cellular network or an Ethernet WiFi network that is connected to the internet. The phone or computer implementing the invention has a camera 410 and a microphone 420 for receiving input from the user. The image data received by the camera and the audio data received by the microphone are fed to a logic to determine the user's mood 430 and a speech recognizer 440 . The logic to determine the user's mood 430 provides as output a representation of the mood and the speech recognizer 440 provides as output a representation of the speech.
[0174] As noted above, persons skilled in the art will recognize many ways the mood-determining logic 430 could operate. For example, Bohacek, U.S. Pat. No. 6,411,687, incorporated herein by reference, teaches that a speaker's gender, age, and dialect or accent can be determined from the speech. Black, U.S. Pat. No. 5,774,591, incorporated herein by reference, teaches about using a camera to ascertain the facial expression of a user and determining the user's mood from the facial expression. Bushey, U.S. Pat. No. 7,224,790, similarly teaches about “verbal style analysis” to determine a customer's level of frustration when the customer telephones a call center. A similar “verbal style analysis” can be used here to ascertain the mood of the user. Combining the technologies taught by Bohacek, Black, and Bushey would provide the best picture of the emotional state of the user, taking many different factors into account.
[0175] Persons skilled in the art will also recognize many ways to implement the speech recognizer 440 . For example, Gupta, U.S. Pat. No. 6,138,095, incorporated herein by reference, teaches a speech recognizer where the words that a person is saying are compared with a dictionary. An error checker is used to determine the degree of the possible error in pronunciation. Alternatively, in a preferred embodiment, a hierarchal stacked neural network, as taught by Commons, U.S. Pat. No. 7,613,663, incorporated herein by reference, could be used. If the neural networks of Commons are used to implement the invention, the lowest level neural network would recognize speech as speech (rather than background noise). The second level neural network would arrange speech into phonemes. The third level neural network would arrange the phonemes into words. The fourth level would arrange words into sentences. The fifth level would combine sentences into meaningful paragraphs or idea structures. The neural network is the preferred embodiment for the speech recognition software because the meanings of words (especially keywords) used by humans are often fuzzy and context sensitive. Rules, which are programmed to process clear-cut categories, are not efficient for interpreting ambiguity.
[0176] The output of the logic to determine mood 430 and the speech recognizer 440 are provided to a conversation logic 450 . The conversation logic selects a conversationally relevant response 452 to the user's verbal (and preferably also image and voice tone) input to provide to the speakers 460 . It also selects a facial expression for the face on the screen 470 . The conversationally relevant response should expand on the user's last statement and what was previously said in the conversation. If the user's last statement included at least one query, the conversationally relevant response preferably answers at least part of the query. If necessary, the conversation logic 450 could consult the internet 454 to get an answer to the query 456 . This could be necessary if the user asks a query such as “Is my grandson James partying instead of studying?” or “What is the weather in New York?”
[0177] To determine whether the user's grandson James is partying or studying, the conversation logic 450 would first convert “grandson James” into a name, such as James Kerner. The last name could be determined either through memory (stored either in the memory of the phone or computer or on a server accessible over the Internet 454 ) of prior conversations or by asking the user, “What is James' last name?” The data as to whether James is partying or studying could be determined using a standard search engine accessed through the Internet 454 , such as Google or Microsoft Bing. While these might not provide accurate information about James, these might provide conversationally relevant information to allow the phone or computer implementing the invention to say something to keep the conversation going. Alternatively, to provide more accurate information the conversation logic 450 could search for information about James Kerner on social networking sites accessible on the Internet 454 , such as Facebook, LinkedIn, Twitter, etc., as well as any public internet sites dedicated specifically to providing information about James Kerner. (For example, many law firms provide a separate web page describing each of their attorneys.) If the user is a member of a social networking site, the conversation logic could log into the site to be able to view information that is available to the user but not to the general public. For example, Facebook allows users to share some information with their “friends” but not with the general public. The conversation logic 450 could use the combination of text, photographs, videos, etc. to learn about James' activities and to come to a conclusion as to whether they constitute “partying” or “studying.”
[0178] To determine the weather in New York, the conversation logic 450 could use a search engine accessed through the Internet 454 , such as Google or Microsoft Bing. Alternatively, the conversation logic could connect with a server adapted to provide weather information, such as The Weather Channel, www.weather.com, or AccuWeather, www.accuweather.com, or the National Oceanic and Atmospheric Administration, www.nws.noaa.gov.
[0179] Note that, to be conversationally relevant, each statement must expand on what was said previously. Thus, if the user asks the question, “What is the weather in New York?” twice, the second response must be different from the first. For example, the first response might be, “It will rain in the morning,” and the second response might be, “It sunny after the rain stops in the afternoon.” However, if the second response were exactly the same as the first, it would not be conversationally relevant as it would not build on the knowledge available to the parties.
[0180] The phone or computer implementing the invention can say arbitrary phrases. In one embodiment, if the voice samples of the person on the screen are available, that voice could be used. In another embodiment, the decision as to which voice to use is made based on the gender of the speaker alone.
[0181] In a preferred embodiment, the image on the screen 470 looks like it is talking.
[0182] When the image on the screen is talking, several parameters need to be modified, including jaw rotation and thrust, horizontal mouth width, lip corner and protrusion controls, lower lip tuck, vertical lip position, horizontal and vertical teeth offset, and tongue angle, width, and length. Preferably, the processor of the phone or computer that is implementing the invention will model the talking head as a 3D mesh that can be parametrically deformed (in response to facial movements during speech and facial gestures).
EXAMPLE 4
Smart Clock Radio
[0183] Another embodiment of this invention illustrated in FIG. 5 , includes a smart clock radio 500 , such as the Sony Dash, adapted to implement the invention. The radio once again includes a camera 510 and a microphone 520 for receiving input from the user. Speakers 530 provide audio output, and a screen 550 provides visual output. The speakers 530 may also be used for other purposes, for example, to play music or news on AM, FM, XM, or Internet radio stations or to play CDs or electronic audio files. The radio is able to connect to the Internet through the home WiFi network 540 . In another embodiment, an Ethernet wire or another wired or wireless connection is used to connect the radio to the Internet.
[0184] In one embodiment, the radio 500 operates in a manner equivalent to that described in the smartphone/laptop embodiment illustrated in FIG. 4 . However, it should be noted that, while a user typically sits in front of a computer or cell phone while she is working with it, users typically are located further away from the clock radio. For example, the clock radio might be located in a fixed corner of the kitchen, and the user could talk to the clock radio while the user is washing the dishes, setting the table or cooking.
[0185] Therefore, in a preferred embodiment, the camera 510 is more powerful than a typical laptop camera and is adapted to viewing the user's face to determine the facial expression from a distance. Camera resolutions on the order of 8-12 megapixels are preferred, although any camera will suffice for the purposes of the invention.
EXAMPLE 5
Television with Set-Top Box
[0186] The next detailed embodiment of the invention illustrated in FIG. 6 , is a television 600 with a set-top box (STB) 602 . The STB is a standard STB, such as a cable converter box or a digital TV tuner available from many cable companies. However, the STB preferably either has or is configured to receive input from a camera 610 and microphone 620 . The output is provided to the user through the TV screen 630 and speakers 640 .
[0187] If the STB has a memory and is able to process machine instructions and connect to the internet (over WiFi, Ethernet or similar), the invention may be implemented on the STB (not illustrated). Otherwise, the STB may connect to a remote server 650 to implement the invention. The remote server will take as input the audio and image data gathered by the STB's microphone and camera. The output provided is an image to display in screen 630 and audio output for speakers 640 .
[0188] The logic to determine mood 430 , speech recognizer 440 , and the conversation logic 450 , which connects to the Internet 454 to provide data for discussion all operate in a manner identical to the description of FIG. 4 .
[0189] When setting up the person to be displayed on the screen, the user needs to either select a default display or send a photograph of a person that the user wishes to speak with to the company implementing the invention. In one embodiment, the image is transmitted electronically over the Internet. In another embodiment, the user mails a paper photograph to an office, where the photograph is scanned, and a digital image of the person is stored.
EXAMPLE 6
Robot with a Face
[0190] FIG. 7 illustrates a special purpose robot 700 designed to implement an embodiment of this invention. The robot receives input through a camera 710 and at least one microphone 720 . The output is provided through a screen 730 , which displays the face of a person 732 , or non-human being, which is either selected by the user or provided by default. There is also at least one speaker 740 . The robot further has joints 750 , which it can move in order to make gestures.
[0191] The logic implementing the invention operates in a manner essentially identical to that illustrated in FIG. 4 . In a preferred embodiment, all of the logic is internal to the robot. However, other embodiments, such as a processor external to the robot connecting to the robot via the Internet or via a local connection, are possible.
[0192] There are some notable differences between the present embodiment and that illustrated in FIG. 4 . In a preferred embodiment, the internet connection, which is essential for conversation logic 450 of FIG. 4 is provided by WiFi router 540 and the robot 700 is able to connect to WiFi. Alternatively, the robot 700 could connect to the internet through a cellular network or through an Ethernet cable. In addition to determining words, voice tone, and facial expression, the conversation logic 450 can now suggest gestures, e.g., wave the right hand, point middle finger, etc. to the robot.
[0193] In one embodiment, the camera is mobile, and the robot rotates the camera so as to continue looking at the user when the user moves. Further, the camera is a three-dimensional camera comprising a structured light illuminator. Preferably, the structured light illuminator is not in a visible frequency, thereby allowing it to ascertain the image of the user's face and all of the contours thereon.
[0194] Structured light involves projecting a known pattern of pixels (often grids or horizontal bars) on to a scene. These patterns deform when striking surfaces, thereby allowing vision systems to calculate the depth and surface information of the objects in the scene. For the present invention, this feature of structured light is useful to calculate and to ascertain the facial features of the user. Structured light could be outside the visible spectrum, for example, infrared light. This allows for the robot to effectively detect the user's facial features without the user being discomforted.
[0195] In a preferred embodiment, the robot is completely responsive to voice prompts and has very few button, all of which are rather larger. This embodiment is preferred because it makes the robot easier to use for elderly and disabled people who might have difficulty pressing small buttons.
[0196] In this disclosure, we have described several embodiments of this broad invention. Persons skilled in the art will definitely have other ideas as to how the teachings of this specification can be used. It is not our intent to limit this broad invention to the embodiments described in the specification. Rather, the invention is limited by the following claims.
[0197] With reference to FIG. 8 , a generic system, such as disclosed in U.S. Pat. No. 7,631,317, for processing program instructions is shown which includes a general purpose computing device in the form of a conventional personal computer 20 , including a processing unit 21 , a system memory 22 , and a system bus 23 that couples various system components including the system memory to the processing unit 21 . The system bus 23 may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. The system memory includes read only memory (ROM) 24 and random access memory (RAM) 25 . A basic input/output system 26 (BIOS) containing the basic routines that help to transfer information between elements within the personal computer 20 , such as during start-up, is stored in ROM 24 . In one embodiment of the present invention on a server computer 20 with a remote client computer 49 , commands are stored in system memory 22 and are executed by processing unit 21 for creating, sending, and using self-descriptive objects as messages over a message queuing network in accordance with the invention. The personal computer 20 further includes a hard disk drive 27 for reading from and writing to a hard disk, not shown, a magnetic disk drive 28 for reading from or writing to a removable magnetic disk 29 , and an optical disk drive 30 for reading from or writing to a removable optical disk 31 such as a CD-ROM or other optical media. The hard disk drive 27 , magnetic disk drive 28 , and optical disk drive 30 are connected to the system bus 23 by a hard disk drive interface 32 , a magnetic disk drive interface 33 , and an optical drive interface 34 , respectively. The drives and their associated computer-readable media provide nonvolatile storage of computer readable instructions, data structures, program modules and other data for the personal computer 20 . Although the exemplary environment described herein employs a hard disk, a removable magnetic disk 29 and a removable optical disk 31 , it should be appreciated by those skilled in the art that other types of computer-readable media which can store data that is accessible by a computer, such as flash memory, network storage systems, magnetic cassettes, random access memories (RAM), read only memories (ROM), and the like, may also be used in the exemplary operating environment.
[0198] A number of program modules may be stored on the hard disk, magnetic disk 29 , optical disk 31 , ROM 24 or RAM 25 , including an operating system 35 , one or more application programs 36 , other program modules 37 , and program data 38 . A user may enter commands and information into the personal computer 20 through input devices such as a keyboard 40 and pointing device 42 . Other input devices (not shown) may include a microphone, joystick, game pad, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit 21 through a serial data interface 46 that is coupled to the system bus, but may be collected by other interfaces, such as a parallel port, game port or a universal serial bus (USB). A monitor 47 or another type of display device is also connected to the system bus 23 via an interface, such as a video adapter 48 . In addition to the monitor, personal computers typically include other peripheral output devices (not shown), such as speakers and printers.
[0199] The personal computer 20 may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 49 , through a packet data network interface to a packet switch data network. The remote computer 49 may be another personal computer, a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of the elements described above relative to the personal computer 20 , although only a memory storage device 50 has been illustrated in FIG. 8 . The logical connections depicted in FIG. 8 include a local area network (LAN) 51 and a wide area network (WAN) 52 . Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets and the Internet.
[0200] When used in a LAN networking environment, the personal computer 20 is connected to the local network 51 through a network interface or adapter 53 . When used in a WAN networking environment, the personal computer 20 typically includes a modem 54 or other elements for establishing communications over the wide area network 52 , such as the Internet. The modem 54 , which may be internal or external, is connected to the system bus 23 via the serial port interface 46 . In a networked environment, program modules depicted relative to the personal computer 20 , or portions thereof, may be stored in the remote memory storage device. It will be appreciated that the network connections shown are exemplary and other elements for establishing a communications link between the computers may be used.
[0201] Typically, a digital data stream from a superconducting digital electronic processing system may have a data rate which exceeds a capability of a room temperature processing system to handle. For example, complex (but not necessarily high data rate) calculations or user interface functions may be more efficiently executed on a general purpose computer than a specialized superconducting digital signal processing system. In that case, the data may be parallelized or decimated to provide a lower clock rate, while retaining essential information for downstream processing.
[0202] The present embodiments are to be considered in all respects as illustrative and not restrictive, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The disclosure shall be interpreted to encompass all of the various combinations and permutations of the elements, steps, and claims disclosed herein, to the extent consistent, and shall not be limited to specific combinations as provided in the detailed embodiments. | An interface device and method of use, comprising audio and image inputs; a processor for determining topics of interest, and receiving information of interest to the user from a remote resource; an audio-visual output for presenting an anthropomorphic object conveying the received information, having a selectively defined and adaptively alterable mood; an external communication device adapted to remotely communicate at least a voice conversation with a human user of the personal interface device. Also provided is a system and method adapted to receive logic for, synthesize, and engage in conversation dependent on received conversational logic and a personality. | 6 |
This application claims the benefit of U.S. Provisional Application No. 61/140,805, filed Dec. 24, 2008, the entirety of which is incorporated by reference herein for all purposes.
FIELD OF THE INVENTION
The invention generally relates to methods and devices for treatment of the ear, which may be supplemental to a tympanocentesis procedure.
BACKGROUND OF THE INVENTION
Middle ear infections are common in young children. Suffering may be alleviated by puncturing the tympanic membrane to evacuate the fluid, a treatment known as tympanocentesis. The patient may undergo general anesthesia prior to a tympanocentesis procedure, but this is not preferred due to cost and health concerns. As a preferable alternative, the tympanic membrane can be locally anesthetized with an iontophoresis procedure. Thus, the patient may be treated while awake. Devices and methods for locally anesthetizing the tympanic membrane are disclosed in co-assigned patent applications U.S. Ser. No. 11/962,063, (now U.S. Pat. No. 8,192,420), U.S. Ser. No. 11/749,729(published as U.S. Pub. No. 2008/0262510), and U.S. 61/085,360, the entireties of which are incorporated by reference herein. FIG. 1A shows a view of an outer ear. The outer ear includes a major element known as the Auricle or Pinna 100 . The outer ear serves as a funnel for directing sounds into the internal portions of the ear. The major physical features of the ear include the Lobule 102 , Concha 104 , Athelix 106 , Helix 108 , Scapha 110 , Triangular fossa 112 , Externam acoustic meatus 114 , Tragus 116 , and Antitragus 118 .
FIG. 1B shows a cross-section of the inner and outer portions of the ear. The pinna 100 is shown connected to the External auditory meatus 118 , or ear canal. The ear canal 118 is shown as a relatively straight passage, but is often a tortuous passageway. The ear canal 118 is connected to the middle ear 120 , which includes the ear drum 122 . The middle ear 120 in turn is connected to the internal ear 124 . When the middle ear 120 becomes infected, fluid swells inside the ear drum 122 . Fluid expansion causes extreme pain to one with a middle ear infection.
Fluid in the middle ear is commonly known as serous otitis media or “effusion”. Effusion is normally drained through the tympanocentesis procedure. However, effusion may thicken and thus be difficult to remove or drain. Thickening of effusion is common with patients who suffer from chronic ear infections. Accordingly, a tympanocentesis procedure may not be effective in patients with lodged or thickened effusion.
Tympanocentesis procedures, which implement iontophoresis, often require iontophoresis fluid to be evacuated before the tympanic membrane is punctured. Evacuation of fluid is commonly performed through low pressure suction via a syringe or suction cannula. Fluid evacuation is often a painful and uncomfortable process because large amounts of noise are created by fluid cavitation. Thus, fluid evacuation by suction may cause pain and emotional discomfort which may prevent the completion of the tympanocentesis procedure. It should be noted that many patients are young, 5 and under, and also have endured many hours or days of a painful ear infection, and thus may be uncooperative and difficult to treat. Fluid may also be removed by swabbing the ear with an absorbent material, however this can be irritating to the patient and ineffective as well. Swabbing also requires the patient to vigorously shake their head side to side, which many young patients refuse to comply with.
BRIEF SUMMARY OF THE INVENTION
One embodiment of the invention may include a method for clearing effusion from an ear. The method may include applying liquid to an ear canal, which is proximal to a perforated tympanic membrane, which is proximal to a middle ear containing effusion. The perforated tympanic membrane may have been intentionally perforated in a prior tympanocentesis procedure. The effusion may not have been removed by the normal tympanocentesis procedure. The method may also include applying an ear device to seal and pressurize the liquid inside the ear canal, the ear device regulating the amount of pressure inside the ear canal. The method may also include inducing a Eustachian tube, which is distal to the middle ear, to open, which causes the fluid to displace the effusion into the Eustachian tube.
Another aspect of the invention may include a method for clearing effusion from an ear, the method including applying an ear device to seal an ear canal, which is proximal to a perforated tympanic membrane, which is proximal to a middle ear containing effusion. The method may also include pressurizing the ear canal with air, and inducing a Eustachian tube, which is distal to the middle ear, to open, which causes the pressurized air to displace the effusion into the Eustachian tube.
Yet another aspect of the invention may include a device for pressurizing an ear canal, the device including a first ear cup which encloses a first external ear, the first ear cup having a first sealing member which fluidly seals around the first external ear, the first ear cup having a first port which is in fluid communication with the sealed first external ear. The device may also include a second ear cup which encloses a second external ear, the second ear cup having a second sealing member which fluidly seals around the second external ear, the second ear cup having a second port which is in fluid communication with the sealed second external ear. A headpiece may connect to each ear cup, the headpiece being configured for applying sealing pressure to each sealing member and retaining each ear cup on each respective external ear.
Yet another aspect of the invention may include a method for clearing liquid from an ear canal, the method including applying a device including a wicking tip to a liquid solution inside an ear canal to wick the liquid from the ear canal. The liquid may be left from a iontophoresis procedure. The method may also include applying negative pressure to the device to aid in wicking the liquid, wherein the wicking tip regulates turbulence to reduce noise caused by wicking the liquid.
Yet another aspect of the invention may include a device for clearing liquid from an ear canal, the device including an elongated cannula including a first end and a second end. The device may also include an elongated foam member including a distal end and a proximal end, a portion of the elongated foam member compressed within the cannula, the distal end uncompressed and exposed past the first end, the proximal end uncompressed and exposed past the second end, wherein the proximal end is larger than the distal end to provide a wicking action to the distal end, and wherein the proximal end will enlarge when fluid is wicked from the distal end into the proximal end.
Yet another aspect of the invention may include a device for silently removing liquid from an ear canal, the device including an elongated multi-lumen cannula including a distal end and a proximal end, wherein each lumen includes a cross-sectional area which reduces cavitation during suction. A suction apparatus may be coupled to the proximal end of the multi-lumen cannula.
Yet another aspect of the invention may include a method for removing liquid from an ear canal, the method including receiving a trigger to apply suction to a device in an ear canal filled with liquid, the device including a lumen for removing the liquid. Suction may be applied to the device. The method may also include monitoring an electrical signal from the device. The method may also include detecting an imminent creation of noise, or noise, caused by the suction; and reducing suction until the imminence of noise, or noise, subsides.
Yet another aspect of the invention may include a system for removing liquid from an ear canal. The system may include a suction probe, which includes at least one noise sensor. A pressure regulator may be coupled to the suction probe, the pressure regulator being configured to supply negative pressure to the suction probe. A processor may also be electrically coupled to the at least one noise sensor and pressure regulator, the processor being configured to detect, based on signals from the at least one noise sensor, imminent creation of noise, or noise, caused by the suction probe, the processor being further configured to modify pressure supplied by the pressure regulator based on the signals.
Yet another aspect of the invention may include a device for silently removing liquid from an ear canal. The device may include an elongated cannula. Filtering material may be disposed within the cannula. A portion of the filtering material may be extended out of an end of the elongated cannula.
Yet another aspect of the invention may include a method for silently removing effusion from a middle ear. A tympanostomy tube including a central lumen may be implanted into a tympanic membrane. A device having an Archimedes' screw may be inserted into the central lumen. The Archimedes' screw may be actuated to remove effusion lodged adjacent to the tympanic membrane.
Yet another aspect of the invention may include a system for silently removing effusion from a middle ear. The system may include a tympanostomy tube including a central lumen. An elongated cannula may be configured to be slidably engaged with the lumen. An Archimedes' screw may be rotatably disposed within the cannula.
To better understand the nature and advantages of the invention, reference should be made to the following description and the accompanying figures. It is to be understood, however, that the figures and descriptions of exemplary embodiments are provided for the purpose of illustration only and are not intended as a definition of the limits of the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A shows a direct view of an outer ear.
FIG. 1B shows a cross-sectional view of an outer, middle, and inner ear, and a Eustachian tube.
FIG. 2A shows a cross-sectional view of an earplug, according to one embodiment of the invention.
FIG. 2B shows a perspective view of an earplug in use, according to one embodiment of the invention.
FIG. 2C shows a flow chart of a method for removing effusion from a middle ear, according to one embodiment of the invention.
FIG. 2D shows a frontal view of a device for sealing both ears of a patient, according to one embodiment of the invention.
FIG. 2E shows a frontal view of a device for sealing both ears of a patient in use, according to one embodiment of the invention.
FIG. 2F shows a perspective view of a device for sealing both ears of a patient, according to one embodiment of the invention.
FIGS. 2G and 2H show frontal and side views, respectively, of a device for sealing both ears of a patient in use, according to one embodiment of the invention.
FIG. 3A shows a side view of a device for silently removing liquid from an ear, according to one embodiment of the invention.
FIGS. 3B and 3C show frontal views of a device for silently removing liquid from an ear in use, according to one embodiment of the invention.
FIGS. 4A-4F show frontal views of liquid removal devices, according to embodiments of the invention.
FIGS. 4G-4I shows frontal views of liquid removal nozzles, according to embodiments of the invention.
FIG. 5A shows a side view of a device for silently removing liquid from an ear, according to one embodiment of the invention.
FIG. 5B shows a cross-sectional view of a device for silently removing liquid from an ear, according to one embodiment of the invention.
FIG. 5C shows a cross-sectional view of a device for silently removing liquid from an ear in use, according to one embodiment of the invention.
FIG. 6A shows a perspective view of a device for silently removing liquid from an ear, according to one embodiment of the invention.
FIG. 6B shows a cross-sectional view of a prior art device for removing liquid from an ear in use.
FIG. 6C shows a cross-sectional view of a device for removing liquid from an ear in use, according to one embodiment of the invention.
FIG. 7A shows a system diagram of a system for silently removing liquid from an ear, according to one embodiment of the invention.
FIG. 7B shows a flow chart for a method for silently removing liquid from an ear, according to one embodiment of the invention.
FIG. 8A shows a cross-sectional view of a device for silently removing liquid from an ear, according to one embodiment of the invention.
FIG. 8B shows a side view of the device of FIG. 8A coupled to a suction catheter, according to one embodiment of the invention.
FIG. 9A shows a cross-sectional view of a device for removing liquid from an ear, according to one embodiment of the invention.
FIG. 9B shows a cross-sectional view of the device of FIG. 9A in use, according to one embodiment of the invention.
FIG. 9C shows a side view of an alternative embodiment of the device of FIG. 9A , according to one embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Effusion Removal:
FIG. 2A shows an earplug 200 , according to one embodiment of the invention. The earplug 200 includes a main lumen 202 . One or more sealing members 204 extend from the main lumen 202 . The sealing members 204 are umbrella shaped, and configured to partially deform within an ear canal to form a fluid tight seal. The sealing members 204 are shown to be integral from the main lumen 202 , but may also be separately attached. The sealing members 204 are preferentially more flexible than the main lumen 202 , as the main lumen 202 should remain at least partially open in use. A lumen seal 206 is placed within the main lumen 202 , which prevents fluid and pressure from exiting the lumen. The lumen seal 206 is shown configured as a duckbill valve, but may include other configurations. For example, the lumen seal 206 may be an elastomeric plug, or wall, with a compressed lumen, which may be expanded by a device for inserting fluid, such as a syringe. The earplug 200 may be constructed from various flexible materials, for example rubber or silicone. Various configurations of the earplug 200 are possible, such as shown in previously incorporated by reference U.S. Provisional Patent Application No. U.S. 61/085,360.
FIG. 2B shows the earplug 200 in use, according to one embodiment of the invention. As shown, a portion of the earplug 200 has been inserted into an ear canal and another portion remains exposed adjacent to the outer ear 208 . The ear shown may have undergone a tympanocentesis procedure, shortly before insertion of the earplug. A sealing member 204 is also shown in a partially compressed state. Thus, the earplug 200 is fluidly sealed within the ear canal. A bulb device 210 or syringe may be coupled with the earplug to supply fluidic pressure into the ear canal. The fluid may be a liquid, such as iontophoresis fluid, saline, or water, or a gas, such as air. As the ear has undergone a tympanocentesis procedure, the tympanic membrane has been punctured, and the ear canal 118 is in fluidic communication with the middle ear 120 . The patient may be instructed to swallow, and thus induce the Eustachian tube to open. This action causes a pressure differential between the Eustachian tube and the ear canal. Thus, fluid in the ear canal will pass through the middle ear, and flush solid or semi-solid effusion inside the middle ear into the Eustachian tube. Alternatively, the bulb device 210 may be used without instructing the patient to swallow. Creating a large enough pressure differential between the ear canal and Eustachian tube will force the Eustachian tube to open and move fluid through the middle ear. Care should be taken to avoid damage to the tympanic membrane. In an alternative embodiment, a relief valve is included to prevent over-pressurization of the ear canal. This procedure may also be performed on both ears simultaneously, and with the patient sitting upright.
FIG. 2C shows a flow chart of a method 212 for removing effusion from a middle ear, according to one embodiment of the invention. In operation 214 , a liquid is applied to the ear canal. The fluid may be liquid such as iontophoresis fluid, saline, or water. The liquid is preferably at room temperature, or higher, in order to prevent discomfort to the patient. In an alternative embodiment, no liquid is provided for operation 214 , and the method begins at operation 216 using only gas as a fluid. At operation 216 an ear device is applied to the ear canal of the patient, to form a fluid tight seal between the ear canal and the surrounding atmosphere. The ear device may, for example, be device 200 as shown in FIGS. 2A and 2B . At operation 218 the ear device is pressurized with fluid, which may be a gas or liquid. The ear device may be pressurized with an external device such as a syringe, catheter, or bulb device as shown in FIG. 2B . At operation 220 the Eustachian tube is induced to open, which may occur from the patient swallowing or from the pressure created in operation 218 . In operation 222 it is determined whether more fluid is required to complete the procedure. If not, then the procedure is complete and ends at 224 . If more fluid is required then the method 212 reverts to operation 218 .
FIG. 2D shows a device 228 for sealing both ears of a patient, according to one embodiment of the invention. The device includes ear cups 230 . Each ear cup 230 includes sealing members 232 , which are configured to fit over and fluidly seal the outer ear of a patient. Each ear cup 230 is provided with a fluid chamber 234 , which fluidly communicates with an ear canal. Each fluid chamber 234 in turn is in fluid communication with a port 236 . The ports 236 include seals 238 for sealing the fluid chambers from the external atmosphere. The seals 238 may be constructed from a flexible material, such as silicone or rubber. The ports 236 may couple to an external device which provides fluidic pressure, for example a syringe, catheter, or bulb device as shown in FIG. 2B . In an alternative embodiment each port 236 is connected to an integral air pump, which pressurizes each fluid chamber when manually or electrically activated. In another alternative embodiment, a relief valve is included to prevent over-pressurization of the ear canal. A band 240 connects each ear cup 230 , and provides spring force for sealing each ear cup 230 to a patient's head. FIG. 2E shows a front view of patient wearing the device 228 .
FIG. 2F shows a device 242 for sealing both ears of a patient, according to one embodiment of the invention. The device includes ear cups 230 , which may be constructed as described regarding FIG. 2D . The device 242 includes a wrap-around headband 242 . The headband 242 wraps around the entire head of a patient, and thus will not easily be disturbed during a procedure. The headband may be constructed from an elastic material, such as rubber or silicone. FIGS. 2G and 2H show side and front views, respectively, of the device 242 in use on a patient.
Silent Liquid Removal:
FIG. 3A shows a device 300 for silently removing liquid from a patient's ear, according to one embodiment of the invention. Removing liquid in the ear after a tympanocentesis procedure may be very disturbing to a patient, as a large amount of noise is created in the ear by conventional suction devices. The device 300 includes a syringe 302 , a nozzle 304 , and an absorbent tip 306 . The syringe 302 provides negative pressure for suctioning and retaining liquid. The nozzle 304 should be flexible to allow insertion into a tortuous ear canal without causing patient discomfort. The nozzle 304 should also be flexible and long enough to reach the tympanic membrane without buckling or kinking. The nozzle 304 may be constructed from a polymer, for example nylon, polycarbonate, polypropylene, polyethylene, silicone, or an annealed or super elastic alloy. The distal portion of the nozzle 304 may include an outer diameter ranging from 0.5-3.0 mm, which allows passage through a speculum and visualization past the nozzle to ensure proper placement within the ear canal. The proximal portion of the nozzle 304 includes a luer fitting for coupling to the syringe 302 . The absorbent tip 306 is located within the distal portion of the nozzle 304 . The absorbent tip 306 may be constructed from absorbent materials such as porous fibers or foam, which will wick liquids. Suitable materials include polyvinyl acetate, rayon, and various blends of the two materials. The absorbent tip 306 may include pore sizes and interstitial spaces which attract liquid and retain particles. The absorbent tip 306 may extend 1-5 mm past the distal portion of the nozzle.
FIG. 3B shows device 300 in use, according to one embodiment of the invention. The device 300 is shown in use in an ear canal model 308 which is partially filled with a liquid solution. The absorbent tip 306 is initially placed in the ear canal and adjacent to the tympanic membrane. Contact with the liquid solution causes an immediate wicking action, which draws the liquid solution into the device 300 . The wicking action is completely silent, and thus will not disturb a patient. FIG. 3C shows the syringe 302 has been slowly drawn back to suction the remaining liquid solution, accordingly, the liquid solution is silently and quickly removed. This method may be performed implementing a one-handed technique by the operator.
FIGS. 4A-4F show devices which may be used in lieu of the syringe 302 with respect to device 300 , according to different embodiments of the invention. FIG. 4A shows a syringe with finger adapters which allows an ergonomic one-handed suction motion. FIG. 4B shows a spring-loaded syringe, which requires minimal effort to use. FIG. 4C shows a otology suction device, which may connect to a standard suction line. FIG. 4D shows a suction bulb, which is compressed before use. FIG. 4E shows a suction pipette, which is compressed before use. FIG. 4F shows a bellows-type suction device, which is compressed before use.
FIGS. 4G-4I show devices which may be used in lieu of the nozzle 304 with respect to device 300 , according to different embodiments of the invention. FIG. 4G shows a straight nozzle, which may offer better visibility in use. FIGS. 4H and 4I show shapeable nozzles of different lengths, which may be shaped in the field by the operator for better access and visibility.
FIGS. 5A and 5B show a device 500 for silently removing liquid from a patient's ear, according to one embodiment of the invention. The device 500 includes an elongated cannula 502 . The elongated cannula 502 may be pre-shaped to include a bend as shown, or in a straight configuration. The elongated cannula 502 may constructed from a malleable metal, and bent in the field by an operator for better access and visibility. The elongated cannula 502 includes an outer diameter which is small enough to reach the tympanic membrane, for example 1-3 mm. An elongated foam member 504 resides within the elongated cannula 502 . The elongated foam member 504 includes a distal foam portion 506 and a proximal foam portion 508 . The distal foam portion 506 extends past the elongated cannula 502 by a small amount, e.g. 1-3 mm, in comparison to the proximal foam portion 508 . A compressed region of foam 510 resides within the elongated cannula, and connects the distal and proximal foam portions. The foam may include pore sizes which can capture particulates.
FIG. 5C shows the device 500 in use, according to one embodiment of the invention. The distal foam portion 506 is shown placed in a liquid solution. The distal foam portion 506 expands slightly upon immersion, but is largely restrained by the elongated cannula. Liquid is wicked silently from the distal foam portion 506 to the proximal foam portion 508 . The proximal foam portion 508 has a larger volume than the distal foam portion 506 , and thus acts as a fluid depository. Accordingly, liquid is wicked from the distal foam portion 506 to the proximal foam portion 508 in a quick and silent manner. The device 500 requires no actuation other than placement in the ear. The proximal foam portion 508 may be compressed to remove wicked fluid and reused during the procedure or in the other ear.
FIG. 6A shows a device 600 for silently removing liquid from a patient's ear, according to one embodiment of the invention. The device 600 is configured as a multi-lumen tube. The tube includes an outer diameter which is small enough to reach the tympanic membrane, for example 1-3 mm. The lumen diameters may range from 0.05-0.5 mm. The device 600 may be connected to a suction device, for example a suction line or syringe. The device may also be flexible or constructed from a malleable material. Noise may be created when air mixes with liquid in a low pressure environment to cause cavitation and create a noisy “slurping” sound, as depicted in prior art device of FIG. 6B . Thus, the larger the inner diameter of the suction device, the more likely noise will be produced, as any given cross-section of a large lumen may occupy both air and water. Device 600 prevents unwanted cavitation by using several smaller diameter lumens, which ensures that only air or water occupies a given cross-section of a lumen at a given time, as shown in FIG. 6C . Accordingly, the device 600 eliminates or greatly reduces cavitation to provide a silent liquid evacuation procedure.
Closed-Loop Control System:
FIG. 7A shows a system 700 for silently removing liquid from a patient's ear, according to one embodiment of the invention. The system 700 is configured to gate the rate of suction, to a device, using a closed loop control method. The system 700 includes a suction probe 702 , which includes a probe tip 704 , and at least one noise sensor 706 . The suction probe 702 may be configured similarly to any of the devices disclosed herein, or may be a standard suction cannula. The sensor 706 may detect noise (e.g. sound) and/or pressure and/or flow rate at or about the probe tip 704 , or any measureable artifact which is related to noise production. For example, as suction noise is caused by turbulence in a liquid stream, which is detectable at the fluid/air interface at the probe tip 704 , detection of turbulence (e.g. presence, discontinuity, increase/decrease) may be used a detectable sensor artifact. Other measureable artifacts include heat/electrical conductivity (e.g. between two points in a probe using the liquid as a conductive medium where conductivity decreases with additional turbulence), evaporation, oxygen content, temperature, or some other micro-environmental variable. Alternatively, several sensors may monitor conditions throughout the entire suction probe 702 . The sensor 706 is electronically coupled to a processor 708 . The processor 708 may be a portion of an embedded computer. A trigger 710 sends user command signals to the processor 708 , for example through a foot or hand switch. The suction probe 702 receives suction from a regulator 714 which is further connected to a suction source 712 . The regulator 714 is electronically coupled to the processor 708 . The processor 708 controls the regulator 714 to vary the rate and amount of negative pressure supplied to the suction probe 702 . The sensor 706 may be configured to detect noise, or the imminent creation of a predetermined noise level, and indicate the noise detection to the processor. The processor 708 may modify, e.g. reduce or eliminate, negative pressure supplied to the suction probe 702 based on the sensor 706 signal. In one example, the sensor is used to sense a waveform which increases in amplitude. Thus, when the waveform increases to a predetermined level in velocity or amplitude, and/or accelerates at a predetermined rate, the processor 708 can reduce negative pressure to the suction probe 702 . Accordingly, the imminent increase/creation of noise to a predetermined level can be abated, as the processor prevents the waveform from increasing. If no noise (e.g. no noise of a significant discomfort level) is sensed by the sensor 706 , then the processor 708 may increase negative pressure to the suction probe until a predetermined level is reached. A test cycle may also be implemented by the processor on start-up or shut-down by sending a test pulse of negative suction to create a suction-wave in the system 700 to check if noise is initially present, which may occur if the probe tip is only partially submerged in liquid, before full negative pressure is enacted by the regulator. Thus, negative pressure may not be applied at a full rate and in a continuous mode if the probe is not fully immersed in liquid. Accordingly, the system 700 automatically prevents the creation of noise during a liquid evacuation procedure, and prevents discomfort to the patient.
The system 700 may include many of the components of a personal computer, such as a data bus, a memory, input and/or output devices (including a touch screen), and the like. The system 700 will often include both hardware and software, with the software typically comprising machine readable code or programming instructions for implementing one, some, or all of the methods described herein. The code may be embodied by a tangible media such as a memory, a magnetic recording media, an optical recording media, or the like. The system 700 may have (or be coupled to) a recording media reader, or the code may be transmitted to the processor 708 by a network connection such as an internet, an intranet, an Ethernet, a wireless network, or the like. Along with programming code, the system 700 may include stored data for implementing the methods described herein, and may generate and/or store data that records parameters reflecting the treatment of one or more patients.
FIG. 7B shows a method 716 for silently removing liquid from a patient's ear, which may be used with system 700 , according to one embodiment of the invention. A trigger occurs at input 716 to supply suction to the suction probe 702 . At operation 720 a processor 708 controls a regulator 714 to supply suction to a suction probe 702 . At operation 722 a sensor 706 monitors noise at a probe tip 704 and sends a signal to the processor 708 . At operation 724 it is determined whether the signal indicates noise, or imminent noise. If no noise, or imminent noise, is detected, then the method 716 loops back to operation 720 . If noise, or imminent noise, is detected, then at operation 726 the processor 708 instructs the regulator 714 to reduce suction. At operation 728 it is again determined whether the signal indicates noise, or imminent noise, after suction reduction. If no noise, or imminent, noise is detected, then the method 716 loops back to operation 720 . If noise, or imminent noise, is detected, then at operation 726 the processor 708 instructs the regulator 714 to reduce suction again. Accordingly, the method 716 automatically prevents the creation of noise during a liquid evacuation procedure, and prevents discomfort to the patient.
FIG. 8A shows a device 800 for silently removing liquid from a patient's ear, according to one embodiment. The device 800 includes a cannula 802 . In one embodiment the cannula 802 is a 0.075″ ID/0.083″ OD PTFE tube approximately 3.2 cm in length, with a 3 / 32 ″ thick polyolefin material heat shrunk about the PTFE tube surface. The device 800 includes a filter material 804 within the cannula 802 . In one embodiment the filter material is 65 thread count cotton gauze strands which are 1.5-1.7 cm long. In one embodiment, the filter material may be fibers of the cotton gauze longitudinally arranged within the cannula 802 . Alternatively, the filter material may be constructed from porous foam strands. A portion 806 of the filter material 804 extends from the distal end of the cannula 802 . The portion 806 may be frayed to resemble a mop head. The device 800 can be coupled to a commercially available 6 Fr suction catheter 808 as shown in FIG. 8B .
In use, the device 800 is applied to a liquid and/or light effusion within a patient's ear and suction is applied to the device 800 , for example, by using the catheter 808 . The filtering material 804 acts as a sound buffer by transferring the suction noise from the extreme distal end of the device to a more proximal location within cannula 802 . In other words, the noise of suction does not occur at the extreme distal end, near the patient's ear drum, but instead occurs more proximally within cannula 802 . Accordingly, the patient is protected from excessive noise due to the suction. The portion 806 extending from the cannula 802 may also cushion against unintended contact with portions of the ear canal and/or be used to physically abrade lodged effusion.
FIGS. 9A and 9B show a system for silently removing liquid from a patient's ear, according to one embodiment of the invention. The device 900 includes a cannula 902 and an Archimedes' screw 904 rotatably disposed within the cannula 902 . The Archimedes' screw 904 may be coupled to a drive motor (not shown) to rotate at a relatively slow revolution, for example at 50-500 RPM, and at a constant torque. The cannula 902 may include a flared tip 906 . The Archimedes' screw 904 may be configured to move in and out of the cannula. The cannula 902 may be configured to pass through a lumen 908 of a tympanostomy tube 910 . A suction source may be coupled to the proximal end of the device 900 .
In use, the tympanostomy tube 910 is first implanted within a tympanic membrane TM of an ear of a patient, as shown. Devices and methods for locally anesthetizing the tympanic membrane for such a tube implant procedure are disclosed in co-assigned patent applications U.S. Ser. No. 11/962,063(now U.S. Pat. No. 8,192,420), U.S. Ser. No. 11/749,729(published as U.S. Pub. No. 2008/0262510), and U.S. 61/085,360, which were incorporated by reference above. The device 900 can then be inserted into the lumen 908 of the tympanostomy tube 910 and applied to a lodged effusion E. The Archimedes' screw 904 may rotate at a relatively slow RPM, and accordingly does not generate excessive noise, i.e. sputtering, to disturb the patient. Rotation of the Archimedes' screw 904 causes the effusion E to engage Archimedes' screw 904 and travel out of the ear canal. The Archimedes' screw 904 may rotate at a constant torque to prevent jamming with particularly thick effusion. The Archimedes' screw 904 may also be actuated in and out of the cannula to help disrupt the lodged effusion. Suction may be applied to the proximal portion of the device 900 to aid in effusion removal.
FIG. 9C shows an alternative embodiment of the device 900 . A cannula 914 includes a laterally exposed portion 914 , which exposes the tip of the Archimedes' screw 904 . The exposed portion 914 may allow the Archimedes' screw 904 to help initiate transport of the effusion.
It should be noted that the silent liquid removal systems and devices shown and described herein may also be used to remove effusion. For example, the silent liquid systems and devices shown and described herein may be inserted into an ear canal to remove effusion. The silent liquid systems and devices shown and described herein may also be inserted directly into the middle ear, following a myringotomy or tympanostomy, to remove lodged effusion. Accordingly, the systems and devices for silent liquid removal described herein are not limited to removing liquid drug solution, and may be used to remove any liquid and fluidic particulates within the ear.
As will be understood by those skilled in the art, the present invention may be embodied in other specific forms without departing from the essential characteristics thereof. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the following claims. | A method is disclosed for clearing effusion from an ear. The method may include applying liquid to an ear canal, which is proximal to a perforated tympanic membrane, which is proximal to a middle ear containing effusion, applying an ear device to seal and pressurize the liquid inside the ear canal, the ear device regulating the amount of pressure inside the ear canal, and inducing a Eustachian tube, which is distal to the middle ear, to open, which causes the fluid to displace the effusion into the Eustachian tube. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] This invention relates to a music content using system that provides the convenience of using a complex music content including encrypted multiple music content materials.
[0003] 2. Background Art
[0004] Systems for copyright protection of music performance data (music content) are conventionally known, as disclosed in Patent Document 1, in which only electronic musical instruments (electronic music machines) that know an encryption key can decrypt and use the encrypted performance data to ensure security. Patent Document 1 is Japanese patent laid-open application No. 2003-208163.
[0005] On the other hand, there are provided systems for allowing users to enjoy variety of music at a time by providing a composite music content including multiple content materials, such as MIDI performance data and logic score data, to electronic music machines, and allowing the electronic music machines to use the multiple content materials.
[0006] In this case, the electronic music machines may not be able to use all the content materials contained in each composite music content file provided, depending on the type and capability of electronic music machine. For example, some electronic music machines may be able to reproduce MIDI performance data from the composite content file including the MIDI performance data as content materials, but not be able to use the logic score data also contained in the composite content because of lack of monitor for displaying a musical score. In such a case, if the composite music content file is encrypted for security, the electronic music machines will have to decrypt all the encrypted content materials including those unusable on the electronic music machines, thereby wasting time on unnecessary decryption.
SUMMARY OF THE INVENTION
[0007] This invention has been made in view of the foregoing situation, and it is an object of the invention to provide a music content using system capable of quickly using a composite music content file including two or more encrypted music content materials.
[0008] According to the main features of the invention, there is provided a music apparatus having a capability of using a composite music content. The inventive music apparatus comprises a storage section that stores a file of the composite music content composed of a plurality of content materials, each of which is encrypted individually, the content materials including a usable content material which matches with the capability of the music apparatus and an unusable content material which does not match with the capability of the music apparatus, an identifying section that identifies the usable content material among the plurality of the content materials of the composite music content stored in the storage section, a decrypting section that selectively decrypts the usable content material identified by the identifying section, and a using section the uses the decrypted usable content material.
[0009] There is also provided a program for use in a music apparatus having a processor and a storage storing a file of a composite music content composed of a plurality of content materials, each of which is encrypted individually, the music apparatus being capable of using at least one of the content materials of the composite music content after decrypted, the content materials of the composite music content stored in the storage including a usable content material which can be used by the music apparatus and an unusable content material which is not used by the music apparatus. The inventive program is executable by the processor for causing the music apparatus to perform a method comprising the steps of identifying the usable content material among the plurality of the content materials of the composite music content stored in the storage, then decrypting the identified usable content material, and using the decrypted usable content material.
[0010] Preferably in the inventive music apparatus, the storage section stores the file of the composite music content such that the plurality of the content materials are arranged in orders predetermined correspondingly to different capabilities required for using the content materials, and the identifying section automatically identifies the usable content material arranged at a particular order predetermined in correspondence to the capability of the music apparatus.
[0011] Otherwise in the inventive music apparatus, the identifying section determines whether each of the plurality of the content materials matches with the capability of the music apparatus so as to identify the usable content material among the plurality of the content materials.
[0012] Preferably in the inventive music apparatus, the storage section stores the composite music content composed of the plurality of the content materials which are encrypted by a code key set commonly to the plurality of the content materials. Otherwise, the storage section stores the composite music content composed of the plurality of the content materials which are encrypted by code keys set differently to the plurality of the content materials.
[0013] In the music content using system according to the invention, when the composite music content file including the multiple kinds of content materials, each encrypted individually, is used on various music content using apparatuses or music information processing apparatuses, only a content material(s) usable on each electronic music machine is decrypted and used.
[0014] According to the invention, each electronic music machine (music content using apparatus or music information processing apparatus) decrypts only a desired kind(s) of content material(s) usable on the electronic music machine. In other words, since other kinds of unusable content materials are not decrypted, the time required for decryption can be reduced.
[0015] Further, the multiple kinds of content materials included in the composite music content file are arranged in the composite music content file in a predetermined and fixed order. Therefore, each electronic music machine decrypts only the content material(s) arranged in a specific location(s) corresponding to the content using capability of the electronic music machine. This makes possible quick use of a desired content material(s) in such a simple manner as to decrypt only the content materials arranged in specific locations in the music content file.
[0016] On the other hand, as mentioned above, when the order of the arrangement of the multiple kinds of content materials is not fixed, each electronic music machine determines whether each content material included in the composite music content file is usable on the electronic music machine, and decrypts only the content material(s) determined to be usable. This also makes possible quick use of content materials even when the locations of the content materials in the composite music content file are uncertain.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a block diagram showing the hardware structure of a music content using system according to a preferred embodiment of the present invention.
[0018] FIG. 2 is a diagram illustrating an example of the format of a composite music content used in the music content using system according to the embodiment of the invention.
[0019] FIG. 3 is a flowchart illustrating an example of the operation for using a music content according to a first embodiment of the present invention.
[0020] FIG. 4 is a flowchart illustrating another example of the operation for using a music content according to a second embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. The embodiments are just examples of the invention and they will therefore be apparent to those skilled in the art that many modifications and variations may be made without departing from the spirit of the invention.
SYSTEM OVERVIEW
[0022] FIG. 1 is a block diagram showing the hardware structure of a music content using system according to one preferred embodiment of the invention. In the example shown, a music content using apparatus EM that forms the main part of the system is a music information processing apparatus capable of processing music information, such as an electronic musical instrument or a personal computer (PC) with a performance operation section and a sound output section, called an electronic music machine. Such an electronic music machine EM includes a central processing unit (CPU) 1 , a random access memory (RAM) 2 , a read only memory (ROM) 3 , an external memory unit 4 , a performance operation detection circuit 5 , a setting operation detection circuit 6 , a display circuit 7 , a sound generator circuit 8 , an effector circuit 9 , a MIDI interface (I/F) 10 , and a communication interface (I/F) 11 . These elements 1 to 11 are connected to one another through a bus 12 .
[0023] The CPU 1 performs various kinds of music information processing including music content using processing in response to clocks from a timer 13 according to various control programs including music content using programs. The RAM 2 is used as a working area for temporary storage of various kinds of data necessary for these kinds of processing. Prestored in the ROM 3 are not only various control programs and parameters, or music information, necessary for these kinds of processing, but also machine number information uniquely assigned to the electronic music machine EM.
[0024] The external memory unit 4 includes an internal storage medium drive for driving an internal storage medium 4 A such as a hard disk (HD), and external storage medium drives for driving various kinds of portable storage media 4 B, such as a compact disk read only memory (CD-ROM), a flexible disk (FD), a magneto-optical (MO) disk, a digital versatile disk (DVD), and a small memory card like Smart Media (trademark). The internal storage medium 4 A can store music information like music contents and control programs acquired from a music content distribution server DS and the like. The external storage media 4 B can also store information acquired by the machine EM. In this case, however, information requiring permission such as a music content is recorded according to predetermined conditions.
[0025] The external storage media 4 B include specific external recording media (specific media) with music contents or music content using programs prerecorded on them. The specific media each have a unique media number, respectively, from which the music contents or the music content using programs can be introduced to the machine EM through each of the external storage medium drives.
[0026] The performance operation detection circuit 5 detects the operating state of each performance operator or control 14 , such as a keyboard or wheel, to introduce performance information to the machine EM according to the detected operating state. The performance operation detection circuit 5 and the performance operators 14 constitute the performance operation section. The setting operation detection circuit 6 detects the operating state of each setting operator or control 15 , such as a character/numeral cursor key, a panel switch, or a mouse, to introduce setting information to the machine EM according to the detected operating state.
[0027] The display circuit 7 drives the display 16 for various screens or various indicators (lamps), and controls these display/lighting states in accordance with instructions from the CPU 1 . These elements 7 and 16 constitute display output section that aids the display of data in response to the operating state of each operator or control 14 , 15 . For example, music information such as performance data (MIDI data) stored in the storage section 3 , 4 can be edited using the display output section. The display output section may also have additional functions for some types of electronic music machines EM, including the function of displaying image data of a musical score or the like included in the music information or music content on the screen of the display 16 , and the function of guiding performance according to performance-aiding data.
[0028] The sound generator circuit 8 generates a tone signal corresponding to performance data from the performance operator 14 or the memory means 3 , 4 . The effector circuit 9 having a DSP for effect impartment gives predetermined effects to the tone signal. A sound system 17 connected to the effector circuit 9 includes a D/A converter, amplifier, and a speaker to generate sound based on the effect-imparted tone signal. These elements 8 , 9 , and 17 constitute a sound output section. The sound output section may also have an audio data processing function for some types of electronic music machines EM. In this case, an audio signal corresponding to audio data (waveform data) included in the music information from the storage section 3 , 4 can be imparted with an effect(s) and outputted to the sound system 17 .
[0029] Further, some types of electronic music machines EM may have printing function and provide a printing section with a printing circuit and a printer (not shown) as an output device in addition to the display output section 7 , 16 , and the sound output section 8 , 9 , 17 . In this case, printing data such as a musical score included in the music information or music content can be printed on the printer.
[0030] The MIDI I/F 10 is connected to another electronic musical instrument (MIDI device) ED so that the music information can be exchanged between the electronic music machine EM and the electronic musical instrument ED. The communication I/F 11 is connected to a communication network CN such as the Internet so that music contents and various control programs for using the music contents can be distributed from one or more music content distribution servers DS and used on the electronic music machine EM.
[0031] Each of the music content distribution servers DS has substantially the same hardware structure as the electronic music machine EM shown in FIG. 1 . As not illustrated in detail here, the music content distribution server DS may not include the performance operation section 5 , 14 , the sound output section 8 , 9 , 17 , and the MIDI I/F 10 , etc.
DATA FORMAT OF MUSIC CONTENT
[0032] FIG. 2 shows the data format of a music content used in the music content using system according to the embodiment of this invention. An outline of the features of the music content using system will be described in brief using FIG. 2 . A composite music content file Cf used in this system includes multiple kinds of content materials A, B, . . . each encrypted individually as indicated by different hatching. For example, the composite music content is a bundle of different contents designed for one music piece, such as MIDI performance data of the music piece, logical score data of the same music piece, and audio data of the same music piece. Generally, electronic music machines are diverse in capabilities of using music data. Some music machines may be equipped with monitors for using the logical score data, while other music machines may lack the capability of using the logical score data. Stated otherwise, the content materials includes a usable content material which matches with the capability of the electronic music machine EM and an unusable content material which does not match with the capability of the electronic music machine EM. When the composite music content file Cf is used on each electronic music machine EM, only a content material(s) usable on the machine are selected and decrypted from the composite music content file Cf. In a first embodiment, the order of the arrangement of the multiple kinds of content materials A, B, . . . in the composite music content file Cf is fixed in advance according to the order of content material chunks Mc 1 , Mc 2 , . . . so that only a content material(s) in a specific location(s) corresponding to the content using function(s) of the machine will be decrypted. In a second embodiment, the order of the arrangement of the content materials is unspecified. Therefore, it is determined for each of the content material chunks Mc 1 , Mc 2 , . . . whether each content is usable on the machine to decrypt only the content material(s) determined to be usable.
[0033] The following describes the data format and the system operation in more detail. Music contents used in this system include a content file Cf called the “composite music content.” As shown in FIG. 2 , the composite music content file Cf includes multiple kinds of music content materials each encrypted individually. Such a composite music content file Cf can be distributed from the music content distribution server DS and stored on the internal storage medium 4 A. Alternatively, it may be recorded on one of portable external recording media (specific media) usable on the electronic music machine EM.
[0034] The composite music content file Cf consists of a plurality of chunks encrypted in a hierarchical fashion, including a header chunk Hc, a code information chunk Cc, a security information chunk Sc, and a plurality of content material chunks Mc 1 , Mc 2 , . . .
[0035] The header chunk Hc describes header information in plaintext or non-encrypted form, such as the content name of the composite music content file Cf, the total number of bytes, the number of chunks, etc. On the other hand, the contents of the other chunks Cc, Sc, Mc 1 , Mc 2 , . . . are encrypted with predetermined keys (encryption keys), respectively, as indicated by different hatching.
[0036] The code information chunk Cc is encrypted with a first encryption key (hereinafter also called “the first key”). The first encryption key is, for example, a machine unique key uniquely assigned to the electronic music machine EM, or a media unique key unique to each of predetermined specific external recording media (specific media). The code information chunk Cc describes information (code information) related to the ciphers, or codes, of the other chunks Sc, Mc 1 , Mc 2 , . . . lower in hierarchy than the code information chunk Cc. For example, the code information describes that the security chunk Sc can be decrypted with a second encryption key and each of the content material chunks Mc 1 , Mc 2 , . . . can be decrypted with a third encryption key, etc.
[0037] The security chunk Sc is encrypted with a second encryption key for the security information chunk (hereinafter also called “the second key”) defined in the code information chunk Cc. The security information chunk Sc describes information (security information) defining security conditions for using each of the content materials Mc 1 , Mc 2 , . . . In other words, the security information represents the limiting conditions for using the content to instruct whether to enable or disable (whether to permit or not permit) each of content using items, such as replay (sound replay, musical score display), editing, duplicate (copying), and printing.
[0038] Each of the content material chunks Mc 1 , Mc 2 , . . . is encrypted with a third encryption key (hereinafter also called “the third key”) defined in the code information chunk Cc. The third encryption key used to encrypt and decrypt each of the content material chunks Mc 1 , Mc 2 , . . . may be a common key for all the content material chunks, or a different key for each content material. A common key may also be used as the second encryption key and the third encryption key.
[0039] Each of the content material chunks Mc 1 , Mc 2 , . . . includes real data that form an actual part of each type of content material, such as MIDI performance data, logic score data, or audio data. For example, the first content material chunk Mc 1 includes MIDI performance data as the content material A, while the second content material chunk Mc 2 includes logic score data as the content material B. The same kind of content materials may be included in two or more content material chunks, such as a case where a piece of MIDI performance data is recorded in the first content material chunk Mc 1 and another piece of MIDI performance data is recorded in the second content material chunk Mc 2 .
[0040] The kind of usable content materials A, B, . . . in such a composite music content file Cf varies according to the type of electronic music machine EM. For example, an X type electronic music machine EMx as a high-end model can use both the content material A (MIDI performance data) and the content material B (logic score data), while a Y type electronic music machine EMy as a low-end mode can use only the content material A (MIDI performance data).
[0041] In the first embodiment of the invention, the content materials A, B, . . . in the composite music content file Cf are arranged in a predetermined, fixed-order according to the order of the multiple content material chunks Mc 1 , Mc 2 , . . . Based on the order of the content materials A, B, the content using programs for each electronic music machine EM are preset according to the type of the machine to decrypt only the material chunks including usable content materials. In the above example, the X type electronic music machine EMx can decrypt the first and second content material chunks Mc 1 , Mc 2 including usable content materials A (MIDI performance data) and B (logic score data), while the Y type electronic music machine EMy can decrypt only the first content material chunk Mc 1 including the content material A (MIDI performance data) as the usable content material.
[0042] On the other hand, in the second embodiment of the invention, the order of the arrangement of the content materials A, B, . . . in the composite music content file Cf is unspecified or irrelevant to the order of the multiple content material chunks Mc 1 , Mc 2 , . . . In this case, the security information chunk Sc in the composite music content file Cf describes material type information representing each of the content materials A, B, . . . in each of the content material chunks Mc 1 , Mc 2 , . . . as part of security information. The electronic music machine EM checks the contents of the material type information to determine whether each of the content material chunks Mc 1 , Mc 2 , . . . includes a content material usable on the machine EM. Then, based on the determination results, the electronic music machine EM decrypts only the content material chunk(s) corresponding to the usable content material(s). Alternatively, part of each content material (e.g., the headmost part) may be described in plaintext or non-encrypted form so that the plaintext part describing the material type information will be used to determine whether the content material is usable.
EXAMPLE OF PROCESSING FLOW OF FIRST EMBODIMENT
[0043] FIG. 3 is a flowchart of “content material using processing 1” representing an example of processing for using a music content according to the first embodiment of the invention. This processing flow shows the operation of the above-mentioned Y type electronic music machine EMy. In the first embodiment, the content materials A, B, . . . in the composite music content file Cf are arranged in the content material chunks Mc 1 , Mc 2 , . . . , respectively, in fixed orders which are predetermined correspondingly to different capabilities required for using the content materials. The electronic music machine EMy automatically identifies the usable content material arranged at a particular order predetermined in correspondence to the capability of the electronic music machine EMy. For example, the Y type electronic music machine EMy that can use only the content material A decrypts only the first material chunk Mc 1 selected from the material chunks Mc 1 , Mc 2 , . . . to read only the first material chunk Mc 1 including the content material A without decrypting the other material chunks Mc 2 , . . .
[0044] In FIG. 3 , at step S 0 , a particular composite music content is selected according to instruction by the user from a plurality of composite music contents stored in the internal storage medium 4 A or a specific portable external storage medium 4 b (one of specific media) of the memory unit 4 . Then the selected composite music content file Cf is loaded onto the RAM 2 from the internal storage medium 4 A or the specific portable external storage medium 4 B of the memory unit 4 , the type Y electronic music machine EMy performs the content material using processing 1 to display the content name and the like on the screen of the display 16 according to the header information of the header chunk Hc in the composite music content file Cf. Then the machine EMy performs the following processing steps S 1 to S 5 .
[0045] In step S 1 , the code information chunk Cc is first decrypted with the first key to determine the second and third keys for decrypting the security information chunk Sc and the content material chunks Mc 1 , Mc 2 , . . . , respectively. Then, in step S 2 , the security information chunk Sc is decrypted with the second key, or key for the security information chunk, obtained from the code information chunk Cc.
[0046] Further, in step S 3 , only the first content material chunk Mc 1 is decrypted with the third key, or key for the content material chunks, obtained from the code information chunk Cc, to read the content material A (performance data) from the content material chunk Mc 1 . In the subsequent step 4 , the decrypted content material A is used as defined in the limiting conditions in the security information of the security information chunk Sc decrypted in step S 2 .
[0047] For example, if the security information dictates that the content material A decrypted in step S 3 is “replayable,” sound will be emitted through the sound output section 8 , 9 , 17 based on the performance data of the content material A. If the security information dictates that it is “editable,” it will mean that the performance data of the content material A can be edited. Further, if it is “replicable,” it will mean that the content material A can be encrypted by a predetermined encryption system and copied to a licensed external recording medium 4 A.
[0048] After completion of using the content material A as the first content material, the procedure goes to the final step S 5 . In step S 5 , if the content material A needs to be restored onto the internal storage medium 4 A after being edited or processed in the content using step S 4 , the composite music content file Cf with the chunks from the chunk Cc to the chunk Mc 1 that have been decrypted and expanded on the RAM 2 is re-encrypted to prevent unauthorized use and stored on the internal storage medium 4 A. Then, the composite music content file Cf is deleted from the RAM 2 to prevent a careless leakage of the content from the RAM 2 . After completion of the reencryption and deletion processing, the content material using processing 1 is ended.
[0049] If the X type electronic music machine EMx, which can use the content materials A and B, performs the content material using processing 1 according to the first embodiment, it will also decrypt the second content material chunk Mc 2 in step S 3 , though not shown in FIG. 3 , after decrypting the first content material chunk Mc 1 . Then, in step S 4 , the content materials A and B of the first and second content material chunks are used.
[0050] Further, even in the case of an electronic music machine EM of any type that can use content materials included in three or more content material chunks, the content materials usable on the machine and the content material chunks that include the content materials are known beforehand. In this case, all the content material chunks usable on the machine are decrypted from the composite music content file Cf in step S 3 of FIG. 3 in the same manner as in the type X electronic music machine EMx. Then, in the next step S 4 , processing for using the content materials included in the decrypted content material chunks is performed.
EXAMPLE OF PROCESSING FLOW OF SECOND EMBODIMENT
[0051] FIG. 4 is a flowchart of “content material using processing 2 ” representing an example of processing for using a music content according to the second embodiment of the invention. This processing flow is applied in common to electronic music machines EM, including the above-mentioned type X and Y electronic music machines EMx and EMy, in the case where the composite music content file Cf has two music content material chunks Mc 1 and Mc 2 . In this flow example according to the second embodiment, it is uncertain which music material in the music content material file Cf is arranged in each of the first and second content material chunks Mc 1 , Mc 2 . Therefore, it is determined whether each of the content materials in the material chunks Mc 1 and Mc 2 is usable on the electronic music machine EM to decrypt the content material(s) determined to be usable. In this case, any unusable content material is not decrypted.
[0052] In FIG. 4 , when the composite music content file Cf is loaded onto the RAM 2 to start the content material using processing 2 , the electronic music machine EM of type X or type Y decrypts the code information chunk Cc with the first key in the first step P 1 in the same manner as in the flow of FIG. 3 to determine the second and third keys for decrypting the security information chunk Sc and the content material chunks Mc 1 , Mc 2 , . . . , respectively. Then, in step P 2 , the security information chunk Sc is decrypted with the second key (key for the security information chunk) obtained from the code information chunk Cc.
[0053] In the subsequent step P 3 , it is determined that the content material included in the first content material chunk Mc 1 is type A according to the material type information included in the security information of the security information chunk Sc decrypted in step P 2 to determine whether the content material A is usable on the electronic music machine EM.
[0054] If it is determined that the content material A in the first content material chunk Mc 1 is usable on the machine like on the type X or Y electronic music machine EMx or EMy (if YES in P 3 ), the procedure goes to step P 4 . Then, in step P 4 , the first content material chunk Mc 1 is decrypted with the third key (key for the content material chunks), obtained from the code information chunk Cc, to read the content material A (performance data) from the first content material chunk Mc 1 .
[0055] After the first content material chunk is decrypted (P 4 ), or when it is determined that the content material A in the content material chunk Mc 1 is unusable on the electronic music machine EM (when No in P 3 ), the procedure goes to step P 5 . Then, in step P 5 , it is determined that the content material included in the second content material chunk Mc 2 is type B according to the material type information to determine whether the content material B is usable on the electronic music machine EM.
[0056] If it is determined that the content material B in the second content material chunk Mc 2 is usable on the machine like on the type X electronic music machine EMx (if YES in P 5 ), the procedure goes to step P 6 . Then, in step P 6 , the second content material chunk Mc 2 is decrypted with the third key, or key for the content material chunks, obtained from the code information chunk Cc, to read the content material B (logic score data) from the second content material chunk Mc 2 .
[0057] After the second content material chunk is decrypted (P 6 ), or when it is determined that the content material B in the second content material chunk Mc 2 is unusable on the machine EM like on the type Y electronic music machine EMy (when No in P 5 ), the procedure goes to step P 7 .
[0058] In step P 7 , each of the decrypted content materials is used according to the security information in the security information chunk Sc decrypted in step P 2 . For example, in the case of the type Y electronic music machine EMy, only the content material A (performance data) decrypted in step P 4 is used according to the contents of the security information. Meanwhile, in the case of the type X electronic music machine EMx, both the content materials A and B decrypted in steps P 4 and P 6 are used according to the contents of the security information.
[0059] After completion of using the content material(s) in step P 7 , the procedure goes to the final step P 8 . In step P 8 , when the content needs to be restored onto the internal storage medium 4 A to prevent a careless leakage of the decrypted content, the composite music content file Cf with the material chunks including the usable content material(s) that have been decrypted and expanded on the RAM 3 is reencrypted and restored on the internal storage medium 4 A. Then, the composite music content file Cf is deleted from the RAM 3 , and the content material using processing 2 is ended.
[0060] When the composite music content file Cf has three or more music content material chunks Mc 1 , Mc 2 , . . . , the content material using processing 2 is applied in common to electronic music machines EM of any type, including the electronic music machines EMx and EMy, by changing part of the procedure as indicated by the broken lines. In other words, after the second content material chunk Mc 2 is decrypted (P 6 ), or when it is determined that the content material B in the content material chunk Mc 2 is unusable (when No in P 5 ), the procedure returns to step P 5 as indicated by the broken lines.
[0061] In this case, in step P 5 , it is determined, in the same manner described above, whether a content material in the subsequent, third content material chunk Mc 3 is usable on the electronic music machine EM. The procedure returns to step P 5 directly or via step P 6 , depending on the determination result in P 5 , thus repeating the processing step P 5 . After completion of determination of the last content material chunk (when NO in P 5 or via P 6 ), the procedure goes to step P 7 to use the content materials decrypted in steps P 4 and P 6 .
[0062] Thus, in the second embodiment, since the locations of the content materials A, B, . . . in the composite music content Cf are uncertain, it is first determined whether each content material included in each content material chunk Mc 1 , Mc 2 , . . . is usable on each electronic music machine EM. Then, only the chunks including usable content materials are decrypted without decrypting the other chunks including unusable content materials.
OTHER VARIOUS EMBODIMENTS
[0063] While the preferred embodiments of the invention have been described, they can be modified in various ways. For example, the aforementioned embodiments assume that each chunk in the composite music content file is encrypted by the same encryption system using the same or different encryption key for each chunk. However, the present invention is not limited to the embodiments, and each chunk may be encrypted by an encryption system different from that for another chunk.
[0064] In the first embodiment, the content materials are arranged in the predetermined order of first MIDI performance data, second logical score data and so on. However, the invention is not limited to this specific order. The order of arranging the content materials may be predetermined differently. However, it should be noted that the order must be predetermined commonly to all the electronic musical machines compliant to the inventive system. | A music apparatus has a capability of using a composite music content. In the music apparatus, a storage section stores a file of the composite music content composed of a plurality of content materials, each of which is encrypted individually. The content materials include a usable content material which matches with the capability of the music apparatus and an unusable content material which does not match with the capability of the music apparatus. In the music apparatus, an identifying section identifies the usable content material among the plurality of the content materials of the composite music content stored in the storage section. Then, a decrypting section selectively decrypts the usable content material identified by the identifying section. Thereafter, a using section uses the decrypted usable content material. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of co-pending application Ser. No. 14/026,598, filed Sep. 13, 2013, which is a divisional application of application Ser. No. 12/140,676, filed Jun. 17, 2008, which is a divisional application of prior application Ser. No. 11/195,147, filed Aug. 2, 2005, now U.S. Pat. No. 7,399,421. The entire contents and disclosures of patent application Ser. Nos. 14/026,598, 12/140,676 and 11/195,147 are hereby incorporated herein by reference in their entireties.
[0002] This application is related to application Ser. No. 11/195,150, filed Aug. 2, 2005, for “Injection Molded Microlenses For Optical Interconnects,” now U.S. Pat. No. 7,295,375, issued Nov. 13, 2007, the disclosure of which is herein incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0003] The present invention relates to a highly efficient wafer-scale microelectronic process for the fabrication of spectral filters, microoptics, optical waveguide arrays and their aligned attachment to optoelectronic semiconductor imaging devices, integrated photonic devices, image displays, optical fiber interconnection, optical backplanes, memory devices, and spectrochemical or biomedical analysis devices.
[0004] Synthetic reconstruction of color images in solid-state analog or digital video cameras is conventionally performed through a combination of an array of optical microlens and spectral filter structures and integrated circuit amplifier automatic gain control operations following a prescribed sequence of calibrations in an algorithm. Fabrication of a planar array of microlenses is conventionally performed by application of a photoresist on a topmost layer of planarized film formed over red, green, blue color filters. By successive processing steps of patterning, developing, etching, followed by thermal reflow, the resist forms approximate plano-convex or hemispherical microlenses. The rheologic properties of the resist will determine the radius of curvature of the microlens elements in the planar array. Coupled with the resist's index of refraction, the resulting microlens array will have a focal length and light-collection properties which may depart from desired optimum performance, including poor control of the fill-factor of the photodiodes in an array comprising the pixel plane. Optical design of the lens shape and refractive index is extremely limited by the necessity to use photoimageable materials with restricted thermal reflow characteristics.
[0005] It is difficult to achieve long focal length high radius of curvature and high refractive index microlens arrays in a single array-plane using conventional microlens forming and fabrication processes. U.S. Pat. No. 6,482,669 B1 summarizes a number of the drawbacks of known solutions in the Prior Art. It is further noted and particularly pointed out that the present invention enables high-volume manufacturing of aspheric microlens arrays. In addition to the foregoing description of fabricating semiconductor color imagers for digital cameras, microlens arrays are also widely employed for high-resolution display monitors and for the coupling of optical waveguides in optical backplanes and optical fibers used in optical communications networks. Electrically addressable lens elements made of various liquid crystal materials are also used in lens assemblies with variable focal length and variable depth of field, or to adjust the image position to accommodate different viewing conditions. These active lens elements are on the order of tens of microns in thickness and can be switched at speeds greater than 85 MHz, enabling full spectrum color imaging without noticeable flicker.
[0006] FIG. 1A exhibits the Prior Art process 100 for the formation of a microlens array: a planar film of a photoimageable material such as a photoresist is photolithographically patterned such that exposure to actinic radiation and subsequent development of the photoresist forms a two-dimensional array of mesas which can be thermally reflowed (melted) into planoconvex microlenses under surface tension forces. An exploded assembly view is shown in 110 , indicating the relative position and alignment of the microlens array elements to an underlying array of red, green, blue color filters and further underlying array of semiconductor photodetectors. By electronically amplifying and combining the outputs of the red, green and blue signals to comprise a unit of image or a picture element termed a pixel, color image formation is achieved. FIG. 1B is an isometric view showing the detailed semiconductor cross-section of the mesa-patterned photoresist 120 before reflow and the resulting planoconvex lens 130 after reflow. Topographical variations caused by the process of integrating color filters into the semiconductor, as shown in FIG. 1B , are a common problem in the Prior Art and typically require additional processing steps for adding a planarizing layer. The focal length required of the microlens elements is the vertical distance projected down to the photodetector array plane.
[0007] As the diameter of the approximately hemispherical microlens is reduced to accommodate increasing imager resolution and pixel density, the precursor photoresist film thickness scales down and the thermal reflow process of the prior art microlens formation process becomes limiting; the radius of curvature and refractive index of the reflowed lens cannot achieve the focal length requirement without significant cross-sectional thinning of the semiconductor device structure. FIG. 1C illustrates the case of collimated incident light 140 collected by planoconvex lens 150 converging a cone of light 170 passing through color filter 160 to focal plane 180 at photodetector 190 . Optically generated cross-talk may result for off-axis incident image light, in spite of measures incorporating metal light shields formed between the color filters, when the optical properties of the microlens are limited by the thermal reflow process of the Prior Art, as demonstrated in FIG. 1D .
SUMMARY OF THE INVENTION
[0008] An object of the present invention is to teach an apparatus for high-volume wafer-scale manufacturing by injection molding of microoptic elements and microspectral filtering devices.
[0009] The conventional definition of a microlens is a lens with a diameter less than one millimeter. Generalizing this definition to the functional elements of optical systems designs, such as refractive or diffractive lenses, mirror/reflectors, Bragg gratings, interferometric devices like Mach-Zender interferometers, mode transformers for waveguide or fiber-optic couplers, variable or fixed optical attenuators, polarizers, compensators, rotators, splitters, combiners, and other devices, it is in accord with the above-mentioned object of the present invention to teach the extension of injection-molding technology down to the order of a micron.
[0010] Another object of the present invention is to provide processes for the wafer-scale fabrication of microoptic devices, which can be integrated into semiconductor structures, such as a color-imaging device for digital cameras. A further object of this invention is to extend this fabrication process to include liquid crystal materials which may be formed into active lens arrays with electronically variable focal length and depth of focus. In accord with another object of the present invention, there is provided a manufacturing method and microelectronic fabrication process sequence which minimizes the number and task-times of the operational unit-process steps required in the reduces of semiconductor arrays for color imaging devices. Production cost minimization is consistent with this latter object of the present invention.
[0011] A further object of the present invention is to teach the manufacturing of aspheric microlenses and lensfilter integration that are not possible with Prior Art technologies. A still further object of the present invention is to provide an apparatus and method for the lithographically precise alignment of arrays of microoptic elements to semiconductor structures, such as integrated color filter arrays and photodiode arrays, and, the attachment thereto.
[0012] Attachment of semiconductor chips to carriers, modules or packages using controlled collapse chip connection (“C4”) technology has proven to provide superior electrical performance parameters, such as minimizing parasitics, mutual inductance, controlled impedance, and noise reduction. It is an object of the present invention to enable the concurrent use of the injection-molding apparatus for the hybrid use of solders for C4 joining of chips to substrates and for optical polymers or glasses for forming and attaching microoptic elements.
[0013] Additional molding features and additional uses for molded microoptic devices are described in copending patent application no. (Attorney Docket YOR920050267US1) for “Injection Molded Microlenses For Parallel Optical Interconnects,” filed herewith, the disclosure of which is hereby incorporated herein by reference in its entirety.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1A illustrates a conventional semiconductor color imager device cross-section.
[0015] FIG. 1B depicts the Prior Art thermal reflow process of forming resist into microlenses.
[0016] FIG. 1C pictures the light cone for image formation by microlenses onto the photodiodes.
[0017] FIG. 1D exhibits the optics for color pixel formation with microlenses and color filters.
[0018] FIG. 2 is a simplified process flow chart describing the sequence and principal features of a preferred injection molded microoptics procedure.
[0019] FIGS. 3A-3D indicate the process description for mold plate fill.
[0020] FIGS. 4A AND 4B are views of the mold plate fill tool scanning injection process.
[0021] FIG. 5 depicts the process sequence for alignment, clamp, transfer, and attachment of microlenses.
[0022] FIG. 6 provides a side view of the fixture frame for mold to wafer alignment and transfer.
[0023] FIG. 7 illustrates the optional post-transfer thermal adjustment of a microlens array.
[0024] FIG. 8 indicates the wafer preparation process description for a microlens interface layer.
[0025] FIG. 9 is a prior art imager cross-section showing alignment of lens, filter and photodiode.
[0026] FIG. 10 shows the integrated red, green and blue color lensfilters of the present invention.
[0027] FIG. 11 illustrates an optical assembly for parallel waveguides or fiber-optic interconnects.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] The present invention teaches an apparatus and method for the formation of planar arrays of microlenses and/or optical waveguides and photonic devices which may comprise, inter alia, optical bus I/O and memory structures in advanced future computer backplanes, image-formation layers on CMOS or CCD solid-state color imagers, matrix arrays of lenses on flat panel displays, and other fields of applications for microoptic elements.
[0029] Unlike conventional art, aspherics, anamorphics, cylindrical lenticular and ellipsoidal microoptic surface designs may be realized with the present invention to provide the long focal lengths required for semiconductor color imaging devices or for VCSEL (vertical cavity surface emitting laser) couplers, particularly those used in parallel optical links including applications such as InfiniB and channels for computers and storage devices. Employment of high refractive index materials, such as polymers, or glasses, or liquid crystal materials, with non-spherical shapes are enabled by the present invention. It is recognized and particularly pointed out that anisotropic etching processes to form cavities in mold plates, including reactive ion etching (RIE) or plasma etching, may be harnessed to create designed microoptics geometries by virtue of differential etch-rates along selected spatial directions, or, by virtue of preferential etching along crystallographic planes. Hence ellipsoidal or aspheric microlens shapes are generated through the controlled ratio of forward to lateral etch-rates in plasma or RIE chambers with defined gas components at specified partial pressures producing designed cavity shapes in a carrier mold plate or template.
[0030] Cavities with desired geometry can be created in a glass plate or other suitable carrier mold material such as polyimide to meet the requirement of various applications. Both wet etching and dry etching techniques have been widely used to etch cavities. The resolution of the wet etching technique is relatively poor due to its isotropic etching characteristics and the undercut it generates. In contrast, reactive ion etching (RIE) has the advantage of controlling the directionality and sidewall profile of the etched cavities. RIE offers good selectivity, little undercut, and high throughput. The process starts by first applying a blanket layer of etch mask material on the glass surface, then patterns it to have the mirror image of the device array on the wafer to which it will subsequently be transferred and attached. The etch mask can be a metal mask, polymer or combination of both. The glass plate is loaded in the RIE tool which generally consists of parallel plate electrodes and an rf power supply. The glass plate is placed on the electrode to which rf power is applied. The plasma of ionized gas is generated between the electrodes. A gas inlet introduces reactive gases, and a pumping system is used to maintain a constant pressure in the etching chamber. The pressures used in RIE are 1 to 20 Pa. Suitable etching gases, such as CF4, CF3, C2F6, CHF3, C3F6, CF4+O2, Cl2F2, CCl4, etc. can be selected so as to produce ionic species which react chemically with glass to form volatile products which spontaneously desorb from the etched glass surface and are removed by the vacuum pump system in the RIE tool. The sidewall profile can be controlled and optimized by parameters such as pressure and flow rate, rf power density (W/cm2), electrode design and the chemical nature of the discharge species.
[0031] Moldplates can also be fabricated by direct laser etching of the cavities. This process is particularly suitable for polyimides or polyimide-on-glass substrates.
[0032] A carrier mold plate with alignment marks and patterned, shaped cavities is designed to generate the microoptic array. Molten polymer or glass is injected to fill the mold plate. A conformal liner of PTFE or other release-film coats the surface of the mold cavities to enable detachment from the mold during transfer and attachment to various devices. Alternatively, plasma etch conditions may be controlled to effect a surface state on the injection mold's cavity walls which is hydrophobic or hydrophilic, thereby aiding the release of the molded microoptic elements. The mold plate coefficient of thermal expansion (CTE) is matched to the target wafer to which the injection molded optical components are bonded. An alternative embodiment employs a layer of polyimide which may either be laser ablated or photoexposed and developed into the array of cavities.
[0033] In order to facilitate release of the microlens material from the mold cavities, well known release agents can be used, including waxes and poly(tetrafluoroethylene) (PTFE) coatings. In addition, a class of materials is well known to form dense, highly ordered monolayer films on silica glass surfaces. These self-assembled monolayers, or SAM's, form because of the tendency of trisilanols to form a tight silyl ether network with silanol groups on the glass surface and with silanol groups on neighboring molecules. The self-ordering films come about from the close packing of long chain alkyl groups attached to the trisilanols. For example, when a wet glass surface is dipped into a dilute solution of octadecyltriethoxysilane or octadecyltrichlorosilane, a well ordered monolayer film assembles on the glass surface. Subsequent baking of the film makes a permanent bond of the film to the surface. Because the end group on the long chain alkyl can have a large number of different functional groups, SAM's allow tuning the surface energy of the glass mold to promote release of the microlenses to the wafer to which they are to be transferred. The SAM's are robust and will survive multiple reuses; and, moreover, when fouled they can easily be removed completely by oxygen ashing and a fresh SAM applied.
[0034] FIG. 2 provides a process flow-chart description of one embodiment of the present invention. In FIG. 2 , two parallel process sequences are shown, one for the filling and inspection of the cavities in a prepared mold plate, and, a second for the preparation of the wafer to be receiving the transferred elements from the cavities of the mold plate. The details of the apparatus design, alignment, transfer, optional reflow, and mold reuse cleaning processes are described in the set of FIGS. 2 through 7 .
[0035] In FIG. 2 , a wafer-scale mold plate 220 with photolithographically formed and etched optical alignment keys 254 and etched cavity array with cavity sidewalls coated with a release layer such as wax, PTFE, a SAM, or other suitable material or plasma process, is injected with a molten lens material 240 . Wafer 210 with etched conjugate optical alignment keys 252 and an optional applied planarizing optical adhesive and refractive index matching layer 230 is brought into alignment by centering alignment key 254 inside key 252 as shown in the aligned state 256 . The alignment process is performed by a conventional photoaligner tool 250 . The microoptic elements formed in the cavities of the mold plate are transferred as shown in 260 to the interface layer 230 . The wafer proceeds to dice, sort and pick 280 for final packaging of the finished device chip, while the mold plate is cleaned and prepared for multiple reuse 270 .
[0036] The process flow details for the mold preparation and injection filling sequence are provided in FIG. 3 steps A,B,C,D. As previously described herein, a patterned array of cavities of designed shape are etched into mold plate 300 by one of the isotropic or anisotropic etch processes taught by the present invention. A conformal release layer 310 is applied to the array of cavities, the preferred composition of which may be selected from the group consisting of fluoropolymers such as PTFE (polytetrafluoroethylene), spray release agents based on wax or zinc oxide, a sacrificial laser ablatable layer or thermally decomposable layer using cavity heaters, self-assembled monolayers or SAMs, trichlorosilane, or other antistiction agents. A fill-tool, described in FIG. 4 , injects dispensed liquid from the fill-head crucible into the array of cavities which will be solidified into microoptic or microspectral filter elements.
[0037] The preferred liquid materials for microlens arrays may be selected from the group consisting of polymers, photopolymers, glasses, sol-gels, UV-curable epoxies, resins, acrylics, cyclolefins, polycarbonates, PMMA (polymethyl methacrylate), polyimide, glass semiconductors such as Ge x Se 1-x , and, combinations using photoinitiators and/or photoreactive agents. Two optional process sequences may next be followed: a first sequence, illustrated in FIG. 3 step C as transmissive microlenses 320 , or a second sequence shown in FIG. 3 step C as spectrally absorptive microlenses which are defined in the present invention by the new term color filterlenses 330 , or simply filterlenses 330 . The filterlenses 330 are taught in the present invention to be the integration of the microlens array with the appropriate red, green and blue array of color filters. The lensfilter represents the combination of a red, green or blue dye-loaded or other color absorbing filter device into the optical polymer or glass comprising the microlens.
[0038] It is recognized and particularly pointed out that extrapolation of the lensfilter concept to other microoptic combinations of image-formation and spectral selection characteristics is subsumed in the present invention, and, that the apparatus and methods taught enable advances in the integration and wafer-scale manufacturing of microoptic products.
[0039] The advantage of parallel processing injection mold microoptics in carrier mold plates concurrently with that of other substrates, such as semiconductor device fabrication (e.g., image sensors or VCSEL wafers), is an important distinction from Prior Art. In particular, microoptics for VCSEL applications require unique characteristics which can more easily be fabricated using injection molding; these include fabrication of interconnected lens arrays which compensate for VCSEL array tolerance runout, compensation for the mismatch between a VCSEL divergence angle (typically 15-20 degrees) and the numerical aperture of an optical fiber or waveguide (which can be as low as 6 degrees) without violating international laser eye safety conditions (such as IEC 825). Accurate formation of the microlens surface is crucial, since due to their size, microlens elements cannot be optically polished using conventional means; the injection molding technique greatly facilitates this aspect of microlens fabrication.
[0040] A further important distinction is the independent inspection and characterization 340 made possible, as shown in FIG. 3 step D, wherein such spectral measurements as transmission spectrophotometry may be utilized for process and product Quality Control against color filter specifications or microlens focal length. The nature of the transparent glass mold enables blank subtraction of the glass transmission spectrum and optimization of dye-loading, film-thickness, microlens cavity depth and shape, and, determines whether rework is required before the microlens array and/or color filter array is committed to the product wafer. In a similar manner, microlens arrays used for VCSEL applications may enable wafer-scale alignment and test of the microlens/VCSEL combinations, wherein the characterization of VCSEL spectral measurements, optical power, and other features may be utilized for product quality control against the VCSEL specifications. If rework is needed, the mold plate is cleaned and prepared as detailed in the process flow chart provided in FIG. 2 . It is also noteworthy that the mold plates can be prepared, filled and characterized against product engineering specifications to build to stock an inventory of parallel processed components, and, concurrently, wafers may similarly be prepared to stock devices which can be finished in manufacturing in a make-to-order operations management model. Consequently, product engineering changes and upgrades at minimum cost are enabled by the present invention.
[0041] FIG. 4 is a schematic representation of the mold plate Fill Tool 400 , comprised of a crucible containing either transmissive molten microlens material 420 for case A, or absorptive color lensfilter material for case B. Either the platen on which the mold plate resides or the dispensing, injection head may be translated relative to the other. Illustrated in FIG. 4 , the Fill-Tool head is selected to be scanned as in 410 relative to the mold plate. A small positive pressure 430 drives fluid flow injection through fill blade 405 to fill a mold plate with cavities 220 ; unfilled cavities 440 ahead of the scan head, and, filled cavities 450 behind the scan head are shown. For the integration of microlens and color filter arrays, lensfilters of green, blue and red are fabricated using fill blade 455 which teaches a configuration for the single-step transfer of lensfilters to a receiving substrate. For CMOS or CCD color imagers the substrate is silicon, and for flat panel displays the substrate may be a glass or polymer plate. For VCSELs, the substrate will be a III-V based semiconductor wafer. The color fill blade 455 is seen to be comprised of a unique configuration of 3 rows, a first blue inject row 460 , a second green inject row 470 , and a third red inject row 480 .
[0042] An alternative embodiment employing the standard fill blade 405 is as follows. Dye-loaded photocurable prepolymers are prepared as red, green and blue fluids and placed in separate crucibles. In a first scan of the fill head, all mold plate cavities are filled by dispensing and injecting the green fluid. A map of the red, green and blue color filter positions in a color imager array is used to selectively expose and photocure the corresponding mold plate cavities for green lensfilters. The remaining cavities are emptied and flushed. All green color filter positions remain in the form of green lensfilters. Again using the design map of color imager filter positions, a second scan dispenses and injects blue fluid into all unfilled cavity positions in the mold plate. Selective exposure cross-links and hardens the blue lensfilters in their cavities, and, all remaining uncured cavities are emptied and flushed. A third scan of the fill head dispenses and injects red fluid in the empty cavities and is cured. Spectrophotometric characterization of the filled template at appropriate stages assures in-spec manufacturing of the color lensfilters, unlike Prior Art processes which are testable only when the product has been completed. The color lensfilters are therefore known good lensfilters before committing them to the transfer to a product substrate; lensfilters are transferred to a color image sensor wafer only when the template is perfect. Significant increase in final product yield and cost reduction results.
[0043] While the process for injection molding of microlenses and of color filters has been taught for the independent cases of fabricating microlenses or integrating color filters with microlenses, it is recognized and particularly pointed out that the independent fabrication of color filters alone is also enabled by the present invention.
[0044] Advantages for molding microlenses include superior shape control, since the microlens elements are shaped by cavities not by surface tension. Laser etching to optical design specifications can be used to augment RIE, plasma or acid wet etched templates. Since the templates are transparent, lenses and spectral filters can be optically characterized in situ in the template. High multiples of reuse of the templates correlate well with lower cost than photolithographic on-wafer processing, resulting in yield improvements by inspection prior to transfer. Single layer arrays of aspheric microlenses provide the equivalence of compound spherical lenses requiring multilayering, with the attendant advantage of a thinner image sensor cross-sectional stack. Thinner image sensors are in turn very desirable for reducing product packaging dimensions. The current industry trend to higher resolution color imagers will similarly benefit from chromatic aberration corrections and color filter compensation for wavelength-dependent index of refraction variations inherent in the red, green, blue color filters of Prior Art.
[0045] The transfer process sequence for injection molded microoptics is given in FIG. 5 . An Alignment-Tool using conventional photolithographic alignment keys aligns the filled template to a substrate such as a silicon CMOS color imager, as shown at 500 . The aligned pair is clamped at 510 , the cavity contents transferred, optionally assisted by an ultrasonic or gas pressure agent, and, separated at 530 .
[0046] FIG. 6 is a sideview of the mold-to-wafer transfer apparatus 600 . Alignment key 254 on mold plate 220 is centered in alignment key 252 on wafer 210 supported on base 630 and contact points 620 inside fixture frame 610 . Molded microlenses 640 are shown in alignment and in contact with the interface layer 800 shown in FIG. 8 .
[0047] After the injection molded microoptic array has been transferred to the receiving device surface, an optional thermal reflow adjustment is shown in FIG. 7 to provide a process for modifying the lens shape and spacing as molded and transferred 700 to a configuration in which the lenses are contiguous 710 , touching at their edges to eliminate gaps. An additional optional step can be added to provide a post-transfer irradiation for index of refraction tuning of the microlenses or an absorbance tuning of the color filters.
[0048] FIG. 8 illustrates the wafer preparation for the interface layer 800 which provides planarization, refractive-index matching to minimize interfacial reflection loss, and adhesion of the transferred microoptic array. Also shown is the alignment of color filter layer 820 to photodetector array 830 integrated in the silicon wafer 810 .
[0049] A semiconductor color imager cross-section is given in FIG. 9 , depicting the aligned positions of the microlens array elements 900 above the color filters 910 and pn photodiodes. The advanced integration of the color filters and microlenses into the color lensfilters 1000 on interface layer 1010 is taught in the present invention as shown in FIG. 10 .
[0050] While one application for microoptic injection molding has been illustrated for solid-state color imaging devices, FIG. 11 exhibits the utility of molding optical assemblies for laser transmitters and receivers in parallel optical interconnects with waveguides or optical fibers, and shows two examples, one for hemicylindrical fibers or waveguides 1110 and square or rectangular fibers or waveguides 1100 .
[0051] Most applications for microlenses or other optical coupling elements will also require electrical interconnects as well, if only for connecting power. Procedures are known for the injection molding of solder bumps onto silicon wafers, and it will be advantageous to have a hybrid process to use injection molding for both optical coupling elements as well as solder electrical interconnects. In this process, the microlenses are fabricated on the wafer as already described. Then a second mold is aligned to the wafer. This second mold has two different sets of cavities. The lower set of cavities is slightly larger than the microlenses to allow the mold to be placed in close contact with the wafer without contacting or damaging the microlenses. The second set of cavities is cylindrical through-holes in the glass mold to allow molten solder to be dispensed through the mold onto the wafers. After cooling, the second mold is separated from the wafer; leaving solder interconnects at the appropriate sites for making electrical contacts when the chips are assembled to the packaging substrates.
[0052] Additional molding features and additional uses for molded microoptic devices are described in copending patent application no. (Attorney Docket YOR920050267US1) for “Injection Molded Microlenses For Parallel Optical Interconnects,” filed herewith, the disclosure of which is hereby incorporated herein by reference in its entirety.
[0053] While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention. | A wafer-scale apparatus and method is described for the automation of forming, aligning and attaching two-dimensional arrays of microoptic elements on semiconductor and other image display devices, backplanes, optoelectronic boards, and integrated optical systems. In an ordered fabrication sequence, a mold plate comprised of optically designed cavities is formed by reactive ion etching or alternative processes, optionally coated with a release material layer and filled with optically specified materials by an automated fluid-injection and defect-inspection subsystem. Optical alignment fiducials guide the disclosed transfer and attachment processes to achieve specified tolerances between the microoptic elements and corresponding optoelectronic devices and circuits. The present invention applies to spectral filters, waveguides, fiber-optic mode-transformers, diffraction gratings, refractive lenses, diffractive lens/Fresnel zone plates, reflectors, and to combinations of elements and devices, including microelectromechanical systems (MEMS) and liquid crystal device (LCD) matrices for adaptive, tunable elements. Preparation of interfacial layer properties and attachment process embodiments are taught. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of U.S. application Ser. No. 10/011,958, filed Nov. 5, 2001, abandoned; which is a continuation-in-part of U.S. application Ser. No. 09/663,607, filed Sep. 18, 2000, now U.S. Pat. No. 6,721,597; and U.S. application Ser. No. 09/663,606, filed Sep. 18, 2000, now U.S. Pat. No. 6,647,292; and the disclosures of these applications are hereby incorporated by reference.
This application is related to U.S. application Ser. No. 10/011,860, filed Nov. 5, 2001 and entitled MONOPHASIC WAVEFORM FOR ANTI-BRADYCARDIA PACING FOR A SUBCUTANEOUS IMPLANTABLE CARDIOVERTER-DEFIBRILLATOR, now U.S. Pat. No. 7,092,754, the disclosure of which application is hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to an apparatus and method for performing electrical cardioversion/defibrillation and optional anti-tachycardia pacing of the heart via a totally subcutaneous non-transvenous system.
BACKGROUND OF THE INVENTION
Defibrillation/cardioversion is a technique employed to counter arrhythmic heart conditions including some tachycardias in the atria and/or ventricles. Typically, electrodes are employed to stimulate the heart with electrical impulses or shocks, of a magnitude substantially greater than pulses used in cardiac pacing. Because current density is a key factor in both defibrillation and pacing, implantable devices may improve what is capable with the standard waveform where the current and voltage decay over the time of pulse deliver. Consequently, a waveform that maintains a constant current over the duration of delivery to the myocardium may improve defibrillation as well as pacing.
Defibrillation/cardioversion systems include body implantable electrodes that are connected to a hermetically sealed container housing the electronics, battery supply and capacitors. The entire system is referred to as implantable cardioverter/defibrillators (ICDs). The electrodes used in ICDs can be in the form of patches applied directly to epicardial tissue, or, more commonly, are on the distal regions of small cylindrical insulated catheters that typically enter the subclavian venous system, pass through the superior vena cava and, into one or more endocardial areas of the heart. Such electrode systems are called intravascular or transvenous electrodes. U.S. Pat. Nos. 4,603,705; 4,693,253; 4,944,300; and 5,105,810, the disclosures of which are all incorporated herein by reference, disclose intravascular or transvenous electrodes, employed either alone, in combination with other intravascular or transvenous electrodes, or in combination with an epicardial patch or subcutaneous electrodes. Compliant epicardial defibrillator electrodes are disclosed in U.S. Pat. Nos. 4,567,900 and 5,618,287, the disclosures of which are incorporated herein by reference. A sensing epicardial electrode configuration is disclosed in U.S. Pat. No. 5,476,503, the disclosure of which is incorporated herein by reference.
In addition to epicardial and transvenous electrodes, subcutaneous electrode systems have also been developed. For example, U.S. Pat. Nos. 5,342,407 and 5,603,732, the disclosures of which are incorporated herein by reference, teach the use of a pulse monitor/generator surgically implanted into the abdomen and subcutaneous electrodes implanted in the thorax. This system is far more complicated to use than current ICD systems using transvenous lead systems together with an active can electrode and therefore it has no practical use. It has in fact never been used because of the surgical difficulty of applying such a device (3 incisions), the impractical abdominal location of the generator and the electrically poor sensing and defibrillation aspects of such a system.
Recent efforts to improve the efficiency of ICDs have led manufacturers to produce ICDs which are small enough to be implanted in the pectoral region. In addition, advances in circuit design have enabled the housing of the ICD to form a subcutaneous electrode. Some examples of ICDs in which the housing of the ICD serves as an optional additional electrode are described in U.S. Pat. Nos. 5,133,353; 5,261,400; 5,620,477; and 5,658,321 the disclosures of which are incorporated herein by reference.
ICDs are now an established therapy for the management of life threatening cardiac rhythm disorders, primarily ventricular fibrillation (V-Fib). ICDs are very effective at treating V-Fib, but are therapies that still require significant surgery.
As ICD therapy becomes more prophylactic in nature and used in progressively less ill individuals, especially children at risk of cardiac arrest, the requirement of ICD therapy to use intravenous catheters and transvenous leads is an impediment to very long term management as most individuals will begin to develop complications related to lead system malfunction sometime in the 5-10 year time frame, often earlier. In addition, chronic transvenous lead systems, their reimplantation and removals, can damage major cardiovascular venous systems and the tricuspid valve, as well as result in life threatening perforations of the great vessels and heart. Consequently, use of transvenous lead systems, despite their many advantages, are not without their chronic patient management limitations in those with life expectancies of >5 years. The problem of lead complications is even greater in children where body growth can substantially alter transvenous lead function and lead to additional cardiovascular problems and revisions. Moreover, transvenous ICD systems also increase cost and require specialized interventional rooms and equipment as well as special skill for insertion. These systems are typically implanted by cardiac electrophysiologists who have had a great deal of extra training.
In addition to the background related to ICD therapy, the present invention requires a brief understanding of a related therapy, the automatic external defibrillator (AED). AEDs employ the use of cutaneous patch electrodes, rather than implantable lead systems, to effect defibrillation under the direction of a bystander user who treats the patient suffering from V-Fib with a portable device containing the necessary electronics and power supply that allows defibrillation. AEDs can be nearly as effective as an ICD for defibrillation if applied to the victim of ventricular fibrillation promptly, i.e., within 2 to 3 minutes of the onset of the ventricular fibrillation.
AED therapy has great appeal as a tool for diminishing the risk of death in public venues such as in air flight. However, an AED must be used by another individual, not the person suffering from the potential fatal rhythm. It is more of a public health tool than a patient-specific tool like an ICD. Because >75% of cardiac arrests occur in the home, and over half occur in the bedroom, patients at risk of cardiac arrest are often alone or asleep and cannot be helped in time with an AED. Moreover, its success depends to a reasonable degree on an acceptable level of skill and calm by the bystander user.
What is needed therefore, especially for children and for prophylactic long-term use for those at risk of cardiac arrest, is a combination of the two forms of therapy which would provide prompt and near-certain defibrillation, like an ICD, but without the long-term adverse sequelae of a transvenous lead system while simultaneously using most of the simpler and lower cost technology of an AED. What is also needed is a cardioverter/defibrillator that is of simple design and can be comfortably implanted in a patient for many years.
SUMMARY OF THE INVENTION
A power supply for an implantable cardioverter-defibrillator for subcutaneous positioning between the third rib and the twelfth rib and using a lead system that does not directly contact a patient's heart or reside in the intrathoracic blood vessels and for providing anti-tachycardia pacing energy to the heart, comprising a capacitor subsystem for storing the anti-tachycardia pacing energy for delivery to the patient's heart; and a battery subsystem electrically coupled to the capacitor subsystem for providing the anti-tachycardia pacing energy to the capacitor subsystem.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the invention, reference is now made to the drawings where like numerals represent similar objects throughout the figures where:
FIG. 1 is a schematic view of a Subcutaneous ICD (S-ICD) of the present invention;
FIG. 2 is a schematic view of an alternate embodiment of a subcutaneous electrode of the present invention;
FIG. 3 is a schematic view of an alternate embodiment of a subcutaneous electrode of the present invention;
FIG. 4 is a schematic view of the S-ICD and lead of FIG. 1 subcutaneously implanted in the thorax of a patient;
FIG. 5 is a schematic view of the S-ICD and lead of FIG. 2 subcutaneously implanted in an alternate location within the thorax of a patient;
FIG. 6 is a schematic view of the S-ICD and lead of FIG. 3 subcutaneously implanted in the thorax of a patient;
FIG. 7 is a schematic view of the method of making a subcutaneous path from the preferred incision and housing implantation point to a termination point for locating a subcutaneous electrode of the present invention;
FIG. 8 is a schematic view of an introducer set for performing the method of lead insertion of any of the described embodiments;
FIG. 9 is a schematic view of an alternative S-ICD of the present invention illustrating a lead subcutaneously and serpiginously implanted in the thorax of a patient for use particularly in children;
FIG. 10 is a schematic view of an alternate embodiment of an S-ICD of the present invention;
FIG. 11 is a schematic view of the S-ICD of FIG. 10 subcutaneously implanted in the thorax of a patient;
FIG. 12 is a schematic view of yet a further embodiment where the canister of the S-ICD of the present invention is shaped to be particularly useful in placing subcutaneously adjacent and parallel to a rib of a patient;
FIG. 13 is a schematic of a different embodiment where the canister of the S-ICD of the present invention is shaped to be particularly useful in placing subcutaneously adjacent and parallel to a rib of a patient;
FIG. 14 is a schematic view of a Unitary Subcutaneous ICD (US-ICD) of the present invention;
FIG. 15 is a schematic view of the US-ICD subcutaneously implanted in the thorax of a patient;
FIG. 16 is a schematic view of the method of making a subcutaneous path from the preferred incision for implanting the US-ICD;
FIG. 17 is a schematic view of an introducer for performing the method of US-ICD implantation;
FIG. 18 is an exploded schematic view of an alternate embodiment of the present invention with a plug-in portion that contains operational circuitry and means for generating cardioversion/defibrillation shock waves; and
FIG. 19 is a graph that shows an example of a monophasic waveform for use in anti-tachycardia pacing in an embodiment of the present invention.
DETAILED DESCRIPTION
Turning now to FIG. 1 , the S-ICD of the present invention is illustrated. The S-ICD consists of an electrically active canister 11 and a subcutaneous electrode 13 attached to the canister. The canister has an electrically active surface 15 that is electrically insulated from the electrode connector block 17 and the canister housing 16 via insulating area 14 . The canister can be similar to numerous electrically active canisters commercially available in that the canister will contain a battery supply, capacitor and operational circuitry. Alternatively, the canister can be thin and elongated to conform to the intercostal space. The circuitry will be able to monitor cardiac rhythms for tachycardia and fibrillation, and if detected, will initiate charging the capacitor and then delivering cardioversion/defibrillation energy through the active surface of the housing and to the subcutaneous electrode. Examples of such circuitry are described in U.S. Pat. Nos. 4,693,253 and 5,105,810, the entire disclosures of which are herein incorporated by reference. The canister circuitry can provide cardioversion/defibrillation energy in different types of waveforms. In one embodiment, a 100 uF biphasic waveform is used of approximately 10-20 ms total duration and with the initial phase containing approximately ⅔ of the energy, however, any type of waveform can be utilized such as monophasic, biphasic, multiphasic or alternative waveforms as is known in the art.
In addition to providing cardioversion/defibrillation energy, the circuitry can also provide transthoracic cardiac pacing energy. The optional circuitry will be able to monitor the heart for bradycardia and/or tachycardia rhythms. Once a bradycardia or tachycardia rhythm is detected, the circuitry can then deliver appropriate pacing energy at appropriate intervals through the active surface and the subcutaneous electrode. Pacing stimuli can be biphasic in one embodiment and similar in pulse amplitude to that used for conventional transthoracic pacing.
This same circuitry can also be used to deliver low amplitude shocks on the T-wave for induction of ventricular fibrillation for testing S-ICD performance in treating V-Fib as is described in U.S. Pat. No. 5,129,392, the entire disclosure of which is hereby incorporated by reference. Also, the circuitry can be provided with rapid induction of ventricular fibrillation or ventricular tachycardia using rapid ventricular pacing. Another optional way for inducing ventricular fibrillation would be to provide a continuous low voltage, i.e., about 3 volts, across the heart during the entire cardiac cycle.
Another optional aspect of the present invention is that the operational circuitry can detect the presence of atrial fibrillation as described in Olson, W. et al. “Onset and Stability for Ventricular Tachyarrhythmia Detection in an Implantable Cardioverter and Defibrillator,” Computers in Cardiology (1986) pp. 167-170. Detection can be provided via R-R Cycle length instability detection algorithms. Once atrial fibrillation has been detected, the operational circuitry will then provide QRS synchronized atrial defibrillation/cardioversion using the same shock energy and waveshape characteristics used for ventricular defibrillation/cardioversion.
The sensing circuitry will utilize the electronic signals generated from the heart and will primarily detect QRS waves. In one embodiment, the circuitry will be programmed to detect only ventricular tachycardias or fibrillations. The detection circuitry will utilize in its most direct form a rate detection algorithm that triggers charging of the capacitor once the ventricular rate exceeds some predetermined level for a fixed period of time: for example, if the ventricular rate exceeds 240 bpm on average for more than 4 seconds. Once the capacitor is charged, a confirmatory rhythm check would ensure that the rate persists for at least another 1 second before discharge. Similarly, termination algorithms could be instituted that ensure that a rhythm less than 240 bpm persisting for at least 4 seconds before the capacitor charge is drained to an internal resistor. Detection, confirmation and termination algorithms as are described above and in the art can be modulated to increase sensitivity and specificity by examining QRS beat-to-beat uniformity, QRS signal frequency content, R-R interval stability data, and signal amplitude characteristics all or part of which can be used to increase or decrease both sensitivity and specificity of S-ICD arrhythmia detection function.
In addition to use of the sense circuitry for detection of V-Fib or V-Tach by examining the QRS waves, the sense circuitry can check for the presence or the absence of respiration. The respiration rate can be detected by monitoring the impedance across the thorax using subthreshold currents delivered across the active can and the high voltage subcutaneous lead electrode and monitoring the frequency in undulation in the waveform that results from the undulations of transthoracic impedance during the respiratory cycle. If there is no undulation, then the patent is not respiring and this lack of respiration can be used to confirm the QRS findings of cardiac arrest. The same technique can be used to provide information about the respiratory rate or estimate cardiac output as described in U.S. Pat. Nos. 6,095,987; 5,423,326; and 4,450,527, the entire disclosures of which are incorporated herein by reference.
The canister of the present invention can be made out of titanium alloy or other presently preferred electrically active canister designs. However, it is contemplated that a malleable canister that can conform to the curvature of the patient's chest will be preferred. In this way, the patient can have a comfortable canister that conforms to the shape of the patient's rib cage. Examples of conforming canisters are provided in U.S. Pat. No. 5,645,586, the entire disclosure of which is herein incorporated by reference. Therefore, the canister can be made out of numerous materials such as medical grade plastics, metals, and alloys. In the preferred embodiment, the canister is smaller than 60 cc volume having a weight of less than 100 gms for long-term wearability, especially in children. The canister and the lead of the S-ICD can also use fractal or wrinkled surfaces to increase surface area to improve defibrillation capability. Because of the primary prevention role of the therapy and the likely need to reach energies over 40 Joules, a feature of one embodiment is that the charge time for the therapy, is intentionally left relatively long to allow capacitor charging within the limitations of device size. Examples of small ICD housings are disclosed in U.S. Pat. Nos. 5,597,956 and 5,405,363, the entire disclosures of which are herein incorporated by reference.
Different subcutaneous electrodes 13 of the present invention are illustrated in FIGS. 1-3 . Turning to FIG. 1 , the lead 21 for the subcutaneous electrode is preferably composed of silicone or polyurethane insulation. The electrode is connected to the canister at its proximal end via connection port 19 which is located on an electrically insulated area 17 of the canister. The electrode illustrated is a composite electrode with three different electrodes attached to the lead. In the embodiment illustrated, an optional anchor segment 52 is attached at the most distal end of the subcutaneous electrode for anchoring the electrode into soft tissue such that the electrode does not dislodge after implantation.
The most distal electrode on the composite subcutaneous electrode is a coil electrode 27 that is used for delivering the high voltage cardioversion/defibrillation energy across the heart. The coil cardioversion/defibrillation electrode is about 5-10 cm in length. Proximal to the coil electrode are two sense electrodes, a first sense electrode 25 is located proximally to the coil electrode and a second sense electrode 23 is located proximally to the first sense electrode. The sense electrodes are spaced far enough apart to be able to have good QRS detection. This spacing can range from 1 to 10 cm with 4 cm being presently preferred. The electrodes may or may not be circumferential with the preferred embodiment. Having the electrodes non-circumferential and positioned outward, toward the skin surface, is a means to minimize muscle artifact and enhance QRS signal quality. The sensing electrodes are electrically isolated from the cardioversion/defibrillation electrode via insulating areas 29 . Similar types of cardioversion/defibrillation electrodes are currently commercially available in a transvenous configuration. For example, U.S. Pat. No. 5,534,022, the entire disclosure of which is herein incorporated by reference, discloses a composite electrode with a coil cardioversion/defibrillation electrode and sense electrodes. Modifications to this arrangement are contemplated within the scope of the invention. One such modification is illustrated in FIG. 2 where the two sensing electrodes 25 and 23 are non-circumferential sensing electrodes and one is located at the distal end, the other is located proximal thereto with the coil electrode located in between the two sensing electrodes. In this embodiment, the sense electrodes are spaced about 6 to about 12 cm apart depending on the length of the coil electrode used. FIG. 3 illustrates yet a further embodiment where the two sensing electrodes are located at the distal end to the composite electrode with the coil electrode located proximally thereto. Other possibilities exist and are contemplated within the present invention. For example, having only one sensing electrode, either proximal or distal to the coil cardioversion/defibrillation electrode with the coil serving as both a sensing electrode and a cardioversion/defibrillation electrode.
It is also contemplated within the scope of the invention that the sensing of QRS waves (and transthoracic impedance) can be carried out via sense electrodes on the canister housing or in combination with the cardioversion/defibrillation coil electrode and/or the subcutaneous lead sensing electrode(s). In this way, sensing could be performed via the one coil electrode located on the subcutaneous electrode and the active surface on the canister housing. Another possibility would be to have only one sense electrode located on the subcutaneous electrode and the sensing would be performed by that one electrode and either the coil electrode on the subcutaneous electrode or by the active surface of the canister. The use of sensing electrodes on the canister would eliminate the need for sensing electrodes on the subcutaneous electrode. It is also contemplated that the subcutaneous electrode would be provided with at least one sense electrode, the canister with at least one sense electrode, and if multiple sense electrodes are used on either the subcutaneous electrode and/or the canister, that the best QRS wave detection combination will be identified when the S-ICD is implanted and this combination can be selected, activating the best sensing arrangement from all the existing sensing possibilities. Turning again to FIG. 2 , two sensing electrodes 26 and 28 are located on the electrically active surface 15 with electrical insulator rings 30 placed between the sense electrodes and the active surface. These canister sense electrodes could be switched off and electrically insulated during and shortly after defibrillation/cardioversion shock delivery. The canister sense electrodes may also be placed on the electrically inactive surface of the canister. In the embodiment of FIG. 2 , there are actually four sensing electrodes, two on the subcutaneous lead and two on the canister. In the preferred embodiment, the ability to change which electrodes are used for sensing would be a programmable feature of the S-ICD to adapt to changes in the patient physiology and size (in the case of children) over time. The programming could be done via the use of physical switches on the canister, or as presently preferred, via the use of a programming wand or via a wireless connection to program the circuitry within the canister.
The canister could be employed as either a cathode or an anode of the S-ICD cardioversion/defibrillation system. If the canister is the cathode, then the subcutaneous coil electrode would be the anode. Likewise, if the canister is the anode, then the subcutaneous electrode would be the cathode.
The active canister housing will provide energy and voltage intermediate to that available with ICDs and most AEDs. The typical maximum voltage necessary for ICDs using most biphasic waveforms is approximately 750 Volts with an associated maximum energy of approximately 40 Joules. The typical maximum voltage necessary for AEDs is approximately 2000-5000 Volts with an associated maximum energy of approximately 200-360 Joules depending upon the model and waveform used. The S-ICD and the US-ICD of the present invention use maximum voltages in the range of about 50 to about 3500 Volts and is associated with energies of about 0.5 to about 350 Joules. The capacitance of the devices can range from about 25 to about 200 micro farads.
In another embodiment, the S-ICD and US-ICD devices provide energy with a pulse width of approximately one millisecond to approximately 40 milliseconds. The devices can provide pacing current of approximately 1 milliamp to approximately 250 milliamps.
The sense circuitry contained within the canister is highly sensitive and specific for the presence or absence of life-threatening ventricular arrhythmias. Features of the detection algorithm are programmable and the algorithm is focused on the detection of V-Fib and high rate V-Tach (>240 bpm). Although the S-ICD of the present invention may rarely be used for an actual life-threatening event, the simplicity of design and implementation allows it to be employed in large populations of patients at modest risk with modest cost by non-cardiac electrophysiologists. Consequently, the S-ICD of the present invention focuses mostly on the detection and therapy of the most malignant rhythm disorders. As part of the detection algorithm's applicability to children, the upper rate range is programmable upward for use in children, known to have rapid supraventricular tachycardias and more rapid ventricular fibrillation. Energy levels also are programmable downward in order to allow treatment of neonates and infants.
Turning now to FIG. 4 , the optimal subcutaneous placement of the S-ICD of the present invention is illustrated. As would be evidence to a person skilled in the art, the actual location of the S-ICD is in a subcutaneous space that is developed during the implantation process. The heart is not exposed during this process and the heart is schematically illustrated in the figures only for help in understanding where the canister and coil electrode are three-dimensionally located in the left mid-clavicular line approximately at the level of the inframammary crease at approximately the 5th rib. The lead 21 of the subcutaneous electrode traverses in a subcutaneous path around the thorax terminating with its distal electrode end at the posterior axillary line ideally just lateral to the left scapula. This way the canister and subcutaneous cardioversion/defibrillation electrode provide a reasonably good pathway for current delivery to the majority of the ventricular myocardium.
FIG. 5 illustrates a different placement of the present invention. The S-ICD canister with the active housing is located in the left posterior axillary line approximately lateral to the tip of the inferior portion of the scapula. This location is especially useful in children. The lead 21 of the subcutaneous electrode traverses in a subcutaneous path around the thorax terminating with its distal electrode end at the anterior precordial region, ideally in the inframammary crease. FIG. 6 illustrates the embodiment of FIG. 1 subcutaneously implanted in the thorax with the proximal sense electrodes 23 and 25 located at approximately the left axillary line with the cardioversion/defibrillation electrode just lateral to the tip of the inferior portion of the scapula.
FIG. 7 schematically illustrates the method for implanting the S-ICD of the present invention. An incision 31 is made in the left anterior axillary line approximately at the level of the cardiac apex. This incision location is distinct from that chosen for S-ICD placement and is selected specifically to allow both canister location more medially in the left inframammary crease and lead positioning more posteriorly via the introducer set (described below) around to the left posterior axillary line lateral to the left scapula. That said, the incision can be anywhere on the thorax deemed reasonable by the implanting physician although in the preferred embodiment, the S-ICD of the present invention will be applied in this region. A subcutaneous pathway 33 is then created medially to the inframammary crease for the canister and posteriorly to the left posterior axillary line lateral to the left scapula for the lead.
The S-ICD canister 11 is then placed subcutaneously at the location of the incision or medially at the subcutaneous region at the left inframammary crease. The subcutaneous electrode 13 is placed with a specially designed curved introducer set 40 (see FIG. 8 ). The introducer set comprises a curved trocar 42 and a stiff curved peel away sheath 44 . The peel away sheath is curved to allow for placement around the rib cage of the patient in the subcutaneous space created by the trocar. The sheath has to be stiff enough to allow for the placement of the electrodes without the sheath collapsing or bending. Preferably the sheath is made out of a biocompatible plastic material and is perforated along its axial length to allow for it to split apart into two sections. The trocar has a proximal handle 41 and a curved shaft 43 . The distal end 45 of the trocar is tapered to allow for dissection of a subcutaneous path 33 in the patient. Preferably, the trocar is cannulated having a central lumen 46 and terminating in an opening 48 at the distal end. Local anesthetic such as lidocaine can be delivered, if necessary, through the lumen or through a curved and elongated needle designed to anesthetize the path to be used for trocar insertion should general anesthesia not be employed. The curved peel away sheath 44 has a proximal pull tab 49 for breaking the sheath into two halves along its axial shaft 47 . The sheath is placed over a guidewire inserted through the trocar after the subcutaneous path has been created. The subcutaneous pathway is then developed until it terminates subcutaneously at a location that if a straight line were drawn from the canister location to the path termination point the line would intersect a substantial portion of the left ventricular mass of the patient. The guidewire is then removed leaving the peel away sheath. The subcutaneous lead system is then inserted through the sheath until it is in the proper location. Once the subcutaneous lead system is in the proper location, the sheath is split in half using the pull tab 49 and removed. If more than one subcutaneous electrode is being used, a new curved peel away sheath can be used for each subcutaneous electrode.
The S-ICD will have prophylactic use in adults where chronic transvenous/epicardial ICD lead systems pose excessive risk or have already resulted in difficulty, such as sepsis or lead fractures. It is also contemplated that a major use of the S-ICD system of the present invention will be for prophylactic use in children who are at risk for having fatal arrhythmias, where chronic transvenous lead systems pose significant management problems. Additionally, with the use of standard transvenous ICDs in children, problems develop during patient growth in that the lead system does not accommodate the growth. FIG. 9 illustrates the placement of the S-ICD subcutaneous lead system such that the problem that growth presents to the lead system is overcome. The distal end of the subcutaneous electrode is placed in the same location as described above providing a good location for the coil cardioversion/defibrillation electrode 27 and the sensing electrodes 23 and 25 . The insulated lead 21 , however, is no longer placed in a taut configuration. Instead, the lead is serpiginously placed with a specially designed introducer trocar and sheath such that it has numerous waves or bends. As the child grows, the waves or bends will straighten out, lengthening the lead system while maintaining proper electrode placement. Although it is expected that fibrous scarring especially around the defibrillation coil will help anchor it into position to maintain its posterior position during growth, a lead system with a distal tine or screw electrode anchoring system 52 can also be incorporated into the distal tip of the lead to facilitate lead stability (see FIG. 1 ). Other anchoring systems can also be used such as hooks, sutures, or the like.
FIGS. 10 and 11 illustrate another embodiment of the present S-ICD invention. In this embodiment, there are two subcutaneous electrodes 13 and 13 ′ of opposite polarity to the canister. The additional subcutaneous electrode 13 ′ is essentially identical to the previously described electrode. In this embodiment, the cardioversion/defibrillation energy is delivered between the active surface of the canister and the two coil electrodes 27 and 27 ′. Additionally, provided in the canister is means for selecting the optimum sensing arrangement between the four sense electrodes 23 , 23 ′, 25 , and 25 ′. The two electrodes are subcutaneously placed on the same side of the heart. As illustrated in FIG. 6 , one subcutaneous electrode 13 is placed inferiorly and the other electrode 13 ′ is placed superiorly. It is also contemplated with this dual subcutaneous electrode system that the canister and one subcutaneous electrode are the same polarity and the other subcutaneous electrode is the opposite polarity.
Turning now to FIGS. 12 and 13 , further embodiments are illustrated where the canister 11 of the S-ICD of the present invention is shaped to be particularly useful in placing subcutaneously adjacent and parallel to a rib of a patient. The canister is long, thin, and curved to conform to the shape of the patient's rib. In the embodiment illustrated in FIG. 12 , the canister has a diameter ranging from about 0.5 cm to about 2 cm with 1 cm being presently preferred. Alternatively, instead of having a circular cross-sectional area, the canister could have a rectangular or square cross-sectional area as illustrated in FIG. 13 without falling outside of the scope of the present invention. The length of the canister can vary depending on the size of the patient's thorax. In an embodiment, the canister is about 5 cm to about 40 cm long. The canister is curved to conform to the curvature of the ribs of the thorax. The radius of the curvature will vary depending on the size of the patient, with smaller radiuses for smaller patients and larger radiuses for larger patients. The radius of the curvature can range from about 5 cm to about 35 cm depending on the size of the patient. Additionally, the radius of the curvature need not be uniform throughout the canister such that it can be shaped closer to the shape of the ribs. The canister has an active surface 15 that is located on the interior (concave) portion of the curvature and an inactive surface 16 that is located on the exterior (convex) portion of the curvature. The leads of these embodiments, which are not illustrated except for the attachment port 19 and the proximal end of the lead 21 , can be any of the leads previously described above, with the lead illustrated in FIG. 1 being presently preferred.
The circuitry of this canister is similar to the circuitry described above. Additionally, the canister can optionally have at least one sense electrode located on either the active surface or the inactive surface and the circuitry within the canister can be programmable as described above to allow for the selection of the best sense electrodes. It is presently preferred that the canister have two sense electrodes 26 and 28 located on the inactive surface of the canisters as illustrated, where the electrodes are spaced from about 1 to about 10 cm apart with a spacing of about 3 cm being presently preferred. However, the sense electrodes can be located on the active surface as described above.
It is envisioned that the embodiment of FIG. 12 will be subcutaneously implanted adjacent and parallel to the left anterior 5th rib, either between the 4th and 5th ribs or between the 5th and 6th ribs. However, other locations can be used.
Another component of the S-ICD of the present invention is a cutaneous test electrode system designed to simulate the subcutaneous high voltage shock electrode system as well as the QRS cardiac rhythm detection system. This test electrode system is comprised of a cutaneous patch electrode of similar surface area and impedance to that of the S-ICD canister itself together with a cutaneous strip electrode comprising a defibrillation strip as well as two button electrodes for sensing of the QRS. Several cutaneous strip electrodes are available to allow for testing various bipole spacings to optimize signal detection comparable to the implantable system.
FIGS. 14 to 18 depict particular US-ICD embodiments of the present invention. The various sensing, shocking and pacing circuitry, described in detail above with respect to the S-ICD embodiments, may additionally be incorporated into the following US-ICD embodiments. Furthermore, particular aspects of any individual S-ICD embodiment discussed above may be incorporated, in whole or in part, into the US-ICD embodiments depicted in the following figures.
Turning now to FIG. 14 , the US-ICD of the present invention is illustrated. The US-ICD consists of a curved housing 1211 with a first and second end. The first end 1413 is thicker than the second end 1215 . This thicker area houses a battery supply, capacitor and operational circuitry for the US-ICD. The circuitry will be able to monitor cardiac rhythms for tachycardia and fibrillation, and if detected, will initiate charging the capacitor and then delivering cardioversion/defibrillation energy through the two cardioversion/defibrillating electrodes 1417 and 1219 located on the outer surface of the two ends of the housing. The circuitry can provide cardioversion/defibrillation energy in different types of waveforms. In one embodiment, a 100 uF biphasic waveform is used of approximately 10-20 ms total duration and with the initial phase containing approximately ⅔ of the energy. However, any type of waveform can be utilized such as monophasic, biphasic, multiphasic or alternative waveforms as is known in the art.
The housing of the present invention can be made out of titanium alloy or other presently preferred ICD designs. It is contemplated that the housing is also made out of biocompatible plastic materials that electronically insulate the electrodes from each other. However, it is contemplated that a malleable canister that can conform to the curvature of the patient's chest will be preferred. In this way the patient can have a comfortable canister that conforms to the unique shape of the patient's rib cage. Examples of conforming ICD housings are provided in U.S. Pat. No. 5,645,586, the entire disclosure of which is herein incorporated by reference. In the preferred embodiment, the housing is curved in the shape of a 5 th rib of a person. Because there are many different sizes of people, the housing will come in different incremental sizes to allow a good match between the size of the rib cage and the size of the US-ICD. The length of the US-ICD will range from about 15 to about 50 cm. Because of the primary preventative role of the therapy and the need to reach energies over 40 Joules, a feature of the preferred embodiment is that the charge time for the therapy intentionally be relatively long to allow capacitor charging within the limitations of device size.
The thick end of the housing is currently needed to allow for the placement of the battery supply, operational circuitry, and capacitors. It is contemplated that the thick end will be about 0.5 cm to about 2 cm wide with about 1 cm being presently preferred. As microtechnology advances, the thickness of the housing will become smaller.
The two cardioversion/defibrillation electrodes on the housing are used for delivering the high voltage cardioversion/defibrillation energy across the heart. In the preferred embodiment, the cardioversion/defibrillation electrodes are coil electrodes. However, other cardioversion/defibrillation electrodes could be used such as having electrically isolated active surfaces or platinum alloy electrodes. The coil cardioversion/defibrillation electrodes are about 5-10 cm in length. Located on the housing between the two cardioversion/defibrillation electrodes are two sense electrodes 1425 and 1427 . The sense electrodes are spaced far enough apart to be able to have good QRS detection. This spacing can range from 1 to 10 cm with 4 cm being presently preferred. The electrodes may or may not be circumferential with the preferred embodiment. Having the electrodes non-circumferential and positioned outward, toward the skin surface, is a means to minimize muscle artifact and enhance QRS signal quality. The sensing electrodes are electrically isolated from the cardioversion/defibrillation electrode via insulating areas 1423 . Analogous types of cardioversion/defibrillation electrodes are currently commercially available in a transvenous configuration. For example, U.S. Pat. No. 5,534,022, the entire disclosure of which is herein incorporated by reference, discloses a composite electrode with a coil cardioversion/defibrillation electrode and sense electrodes. Modifications to this arrangement are contemplated within the scope of the invention. One such modification is to have the sense electrodes at the two ends of the housing and have the cardioversion/defibrillation electrodes located in between the sense electrodes. Another modification is to have three or more sense electrodes spaced throughout the housing and allow for the selection of the two best sensing electrodes. If three or more sensing electrodes are used, then the ability to change which electrodes are used for sensing would be a programmable feature of the US-ICD to adapt to changes in the patient physiology and size over time. The programming could be done via the use of physical switches on the canister or, as presently preferred, via the use of a programming wand or via a wireless connection to program the circuitry within the canister.
Turning now to FIG. 15 , the optimal subcutaneous placement of the US-ICD of the present invention is illustrated. As would be evident to a person skilled in the art, the actual location of the US-ICD is in a subcutaneous space that is developed during the implantation process. The heart is not exposed during this process and the heart is schematically illustrated in the figures only for help in understanding where the device and its various electrodes are three-dimensionally located in the thorax of the patient. The US-ICD is located between the left mid-clavicular line approximately at the level of the inframammary crease at approximately the 5 th rib and the posterior axillary line, ideally just lateral to the left scapula. This way the US-ICD provides a reasonably good pathway for current delivery to the majority of the ventricular myocardium.
FIG. 16 schematically illustrates the method for implanting the US-ICD of the present invention. An incision 1631 is made in the left anterior axillary line approximately at the level of the cardiac apex. A subcutaneous pathway is then created that extends posteriorly to allow placement of the US-ICD. The incision can be anywhere on the thorax deemed reasonable by the implanting physician although in the preferred embodiment, the US-ICD of the present invention will be applied in this region. The subcutaneous pathway is created medially to the inframammary crease and extends posteriorly to the left posterior axillary line. The pathway is developed with a specially designed curved introducer 1742 (see FIG. 17 ). The trocar has a proximal handle 1641 and a curved shaft 1643 . The distal end 1745 of the trocar is tapered to allow for dissection of a subcutaneous path in the patient. Preferably, the trocar is cannulated having a central lumen 1746 and terminating in an opening 1748 at the distal end. Local anesthetic such as lidocaine can be delivered, if necessary, through the lumen or through a curved and elongated needle designed to anesthetize the path to be used for trocar insertion should general anesthesia not be employed. Once the subcutaneous pathway is developed, the US-ICD is implanted in the subcutaneous space, the skin incision is closed using standard techniques.
As described previously, the US-ICDs of the present invention vary in length and curvature. The US-ICDs are provided in incremental sizes for subcutaneous implantation in different sized patients. Turning now to FIG. 18 , a different embodiment is schematically illustrated in exploded view which provides different sized US-ICDs that are easier to manufacture. The different sized US-ICDs will all have the same sized and shaped thick end 1413 . The thick end is hollow inside allowing for the insertion of a core operational member 1853 . The core member comprises a housing 1857 which contains the battery supply, capacitor and operational circuitry for the US-ICD. The proximal end of the core member has a plurality of electronic plug connectors. Plug connectors 1861 and 1863 are electronically connected to the sense electrodes via pressure fit connectors (not illustrated) inside the thick end which are standard in the art. Plug connectors 1865 and 1867 are also electronically connected to the cardioverter/defibrillator electrodes via pressure fit connectors inside the thick end. The distal end of the core member comprises an end cap 1855 , and a ribbed fitting 1859 which creates a water-tight seal when the core member is inserted into opening 1851 of the thick end of the US-ICD.
The S-ICD and US-ICD, in alternative embodiments, have the ability to detect and treat atrial rhythm disorders, including atrial fibrillation. The S-ICD and US-ICD have two or more electrodes that provide a far-field view of cardiac electrical activity that includes the ability to record the P-wave of the electrocardiogram as well as the QRS. One can detect the onset and offset of atrial fibrillation by referencing to the P-wave recorded during normal sinus rhythm and monitoring for its change in rate, morphology, amplitude and frequency content. For example, a well-defined P-wave that abruptly disappeared and was replaced by a low-amplitude, variable morphology signal would be a strong indication of the absence of sinus rhythm and the onset of atrial fibrillation. In an alternative embodiment of a detection algorithm, the ventricular detection rate could be monitored for stability of the R-R coupling interval. In the examination of the R-R interval sequence, atrial fibrillation can be recognized by providing a near constant irregularly irregular coupling interval on a beat-by-beat basis. An R-R interval plot during AF appears “cloudlike” in appearance when several hundred or thousands of R-R intervals are plotted over time when compared to sinus rhythm or other supraventricular arrhythmias. Moreover, a distinguishing feature compared to other rhythms that are irregularly irregular, is that the QRS morphology is similar on a beat-by-beat basis despite the irregularity in the R-R coupling interval. This is a distinguishing feature of atrial fibrillation compared to ventricular fibrillation where the QRS morphology varies on a beat-by-beat basis. In yet another embodiment, atrial fibrillation may be detected by seeking to compare the timing and amplitude relationship of the detected P-wave of the electrocardiogram to the detected QRS(R-wave) of the electrocardiogram. Normal sinus rhythm has a fixed relationship that can be placed into a template matching algorithm that can be used as a reference point should the relationship change.
In other aspects of the atrial fibrillation detection process, one may include alternative electrodes that may be brought to bear in the S-ICD or US-ICD systems either by placing them in the detection algorithm circuitry through a programming maneuver or by manually adding such additional electrode systems to the S-ICD or US-ICD at the time of implant or at the time of follow-up evaluation. One may also use electrodes for the detection of atrial fibrillation that may or may not also be used for the detection of ventricular arrhythmias given the different anatomic locations of the atria and ventricles with respect to the S-ICD or US-ICD housing and surgical implant sites.
Once atrial fibrillation is detected, the arrhythmia can be treated by delivery of a synchronized shock using energy levels up to the maximum output of the device therapy for terminating atrial fibrillation or for other supraventricular arrhythmias. The S-ICD or US-ICD electrode system can be used to treat both atrial and ventricular arrhythmias not only with shock therapy but also with pacing therapy. In a further embodiment of the treatment of atrial fibrillation or other atrial arrhythmias, one may be able to use different electrode systems than what is used to treat ventricular arrhythmias. Another embodiment would be to allow for different types of therapies (amplitude, waveform, capacitance, etc.) for atrial arrhythmias compared to ventricular arrhythmias.
The core member of the different sized and shaped US-ICD will all be the same size and shape. That way, during an implantation procedure, multiple sized US-ICDs can be available for implantation, each one without a core member. Once the implantation procedure is being performed, then the correct sized US-ICD can be selected and the core member can be inserted into the US-ICD and then programmed as described above. Another advantage of this configuration is when the battery within the core member needs replacing it can be done without removing the entire US-ICD.
To ensure adequate pacing capture of the heart through an S-ICD having a subcutaneous only lead system, pacing therapy can be enhanced by using a monophasic waveform of the present invention for pacing. In addition, to further compensate for the lack of direct contact with the heart, the subcutaneous electrode system, especially the anterior thoracic electrode system, that will be delivering the ATP stimuli should result in as high as a current density as possible in order to activate the cardiac tissues. This can be facilitated by using an electrode as close to the sternum as possible in the tissues overlying the right ventricle, the cardiac chamber closest to the anterior subcutaneous space where the S-ICD of the present invention will lie.
FIG. 19 is a graph that shows an embodiment of the example of a monophasic waveform for use in ATP applications in S-ICD and US-ICD devices in an embodiment of the present invention. As shown in FIG. 19 , the monophasic waveform is plotted as a function of time versus instantaneous voltage.
In one embodiment, the monophasic waveform 1902 is an initial positive voltage 1904 , a positive decay voltage 1906 and a final positive voltage 1908 . In another embodiment, the polarities of the monophasic waveform 1902 can be reversed such that the waveform 1902 is negative in polarity.
As shown in FIG. 19 , the monophasic waveform 1902 is initially at zero voltage. Upon commencement of ATP, a voltage of positive polarity is provided and the monophasic waveform 1902 rises to the initial positive voltage 1904 . Next, the voltage of the monophasic waveform 1902 decays along the positive decay voltage 1906 until reaching a voltage level at the final positive voltage 1908 . At this point, the monophasic waveform 1902 is truncated.
The total amount of time that the monophasic waveform 1902 comprises is known as the “pulse width.” In an embodiment, the pulse width of the monophasic waveform 1902 can range from approximately 1 millisecond to approximately 40 milliseconds. The total amount of energy delivered is a function of the pulse width and the average (absolute) value of the voltage. The ratio of the final positive voltage 1908 to the initial positive voltage 1904 is known as the “tilt” of the waveform.
An example of one embodiment of the monophasic waveform 1902 will now be described. In this embodiment, the amplitude of the initial positive voltage 1904 can range from approximately 0.1 to approximately 100 volts. In one example, the amplitude of the initial positive voltage 1904 is approximately 20 volts. In addition, in an example, the tilt of the positive decay voltage 1906 is approximately 50%. Typically, the tilt of the positive decay voltage 1906 can range from approximately 5% to approximately 95% although the waveform tilt can be considerably higher or lower, depending on variables such as capacitance, tissue resistance and type of electrode system used.
In the example, the pulse width of the monophasic waveform 1902 can range from approximately 1 millisecond to approximately 40 milliseconds. In addition, the implantable cardioverter-defibrillator employs anti-tachycardia pacing at rates of approximately 100 to approximately 350 stimuli/minute for ventricular tachycardia episodes. In addition, up to 30 ATP stimuli for any single attempt could be allowed and as many as 15 ATP attempts could be allowed for any effort to terminate a single episode of VT. One might also allow for different ATP methods to be employed for VTs of different rates or ECG characteristics. Moreover, the device may be allowed to auto-select the method of ATP to be used based upon the device's and/or the physician's experience with previous episodes of VT or with the patient's underlying cardiac condition.
Although it possible for the present invention to provide standard ATP at predetermined or preprogrammed rates for monomorphic VT, the use of an S-ICD may also be employed for the treatment of other arrhythmias such as atrial tachyarrhythmias.
The S-ICD and US-ICD devices and methods of the present invention may be embodied in other specific forms without departing from the teachings or essential characteristics of the invention. The described embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore to be embraced therein. | A power supply for an implantable cardioverter-defibrillator for subcutaneous positioning between the third rib and the twelfth rib and using a lead system that does not directly contact a patient's heart or reside in the intrathoracic blood vessels and for providing anti-tachycardia pacing energy to the heart, comprising a capacitor subsystem for storing the anti-tachycardia pacing energy for delivery to the patient's heart; and a battery subsystem electrically coupled to the capacitor subsystem for providing the anti-tachycardia pacing energy to the capacitor subsystem. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority right of prior U.S. patent application Ser. No. 61/076,171 filed on Jun. 27, 2008 by applicants herein.
TECHNICAL FIELD
[0002] The invention relates generally to the field of aerodynamics and more particularly to a system and method for the control of vibration of helicopter rotor blades.
BACKGROUND TO THE INVENTION
[0003] As those skilled in the art are aware, both flow control and structural control devices can be employed on each rotating rotor blade of a helicopter to minimize vibration in flight. The most efficient method of reducing vibration on helicopter rotor blades is through Individual Blade Control (IBC) in which each rotor blade is individually controlled using a flow control or structural control device.
[0004] Structural control includes any devices capable of controlling the mass, stiffness or damping of the helicopter blade. The only practical structural control device developed to date is the Active Pitch Link, which is able to control the torsional stiffness characteristics of a blade.
[0005] Flow control can be defined as any control technique capable of controlling the aerodynamic loads acting on the blade. Such techniques include Actively Controlled Flap (ACF), Active Twist Rotor (ATR), Actively Controlled Tip (ACT), along with various types of Boundary Layer Suction/Blowing devices. For helicopters, the two most popular techniques have been the Actively Controlled Flap (ACF) and Active Twist Rotor (ATR).
[0006] There are a number of major research teams worldwide investigating the feasibility of various active control technologies on helicopter rotor blades. Of the research presently being performed, all research teams consider only one control system per blade. The most popular vibration control systems are of the flow control type with the most popular control system in this category being ACF because of the significantly lower power requirement than ATR. Some prior art systems have applied ACF with two independently controlled flaps on a single blade i.e. two independent control systems of the same type.
[0007] However, the problem with applying only one type of control device, especially actively controlled flap (ACF) or active twist rotor (ATR), is that these devices are not very efficient on their own. This is due to the fact that both of these technologies try to actively control the twist (or effective pitch angle) of the rotor blades. This is clearly the goal of a rotor blade employing ATR, but even with ACF it has been shown that a flap is much more efficient when used as a servo-tab than when used as a high-lift device. The goal of a servo-tab is to twist the rotor blade as a result of the flap deflection whereas the goal of the high-lift device is to increase the local rotor blade section lift of a rigid blade.
[0008] In order to impose the highest possible twist effect, either as a result of employing ACF or ATR technology, the rotor blade torsional stiffness should be as low as possible. However, the torsional stiffness of a helicopter rotor blade is set to a certain level to avoid excessive deformations due to the aerodynamic loads during operation. This level cannot be lowered by simply making softer blades; otherwise the blades would become too flexible and aeroelastic problems and loss of aerodynamic efficiency would occur.
[0009] Therefore, there is a need in the art for some kind of control system allowing the rotor blade torsional stiffness to be lowered whenever the flow control device is actuated.
SUMMARY OF THE INVENTION
[0010] Certain exemplary embodiments may provide a feedback control system for controlling vibration in a rotor blade, wherein the rotor blade is coupled to a rotor hub and has at least a torsional stiffness and a pitch angle associated therewith, the feedback control system comprising: a flow control device for adjusting the pitch angle of the rotor blade; a structural control device for adjusting the torsional stiffness of the rotor blade; a plurality of sensors attached to the rotor blade; and a control computer communicating with the flow control device, the structural control device and the plurality of sensors, wherein vibration data from the sensors is received by the control computer and control signals are generated by the control computer to reduce the torsional stiffness of the rotor blade with the structural control device and simultaneously increase the pitch angle of the rotor blade with the flow control device.
[0011] Certain other exemplary embodiments may provide a method of controlling vibration in a rotor blade, wherein the rotor blade is coupled to a rotor hub and has at least a torsional stiffness and a pitch angle associated therewith, the method comprising the steps of: receiving vibration data from a plurality of sensors into a control computer, wherein the control computer communicates with a flow control device, a structural control device and the plurality of sensors, wherein each of the flow control device, the structural control device and the plurality of sensors are electromechanically coupled to the rotor blade; generating control signals in the control computer; adjusting the structural control device to reduce the torsional stiffness of the rotor blade based on the control signals inputted therein; and simultaneously adjusting the flow control device to increase the pitch angle of the rotor blade based on the control signals inputted therein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The invention will now be described with reference to the drawings in which:
[0013] FIG. 1A depicts an overview of the rotor blade incorporating the hybrid vibration control device of the present invention;
[0014] FIG. 1B depicts the sensors integral to the hybrid device of FIG. 1A ;
[0015] FIG. 2A depicts the main parts of a prior art helicopter rotor hub;
[0016] FIG. 2B depicts a collective change of the pitch angle of the rotor blades of FIG. 2A ;
[0017] FIG. 2C depicts a cyclical change of the pitch angle of the rotor blades of FIG. 2A ;
[0018] FIG. 3A depicts a prior art smart spring;
[0019] FIG. 3B depicts the smart spring of FIG. 3A with the actuator off;
[0020] FIG. 3C depicts the smart spring of FIG. 3A with the actuator on;
[0021] FIG. 4A depicts schematically the smart spring used in an active pitch link (APL) in the hybrid device of the present invention;
[0022] FIG. 4B depicts the primary (fail safe) load path of the smart spring of FIG. 4A ;
[0023] FIG. 4C depicts the secondary load path of the smart spring of FIG. 4A ;
[0024] FIG. 4D depicts a perspective view of the active pitch link (APL) in accordance with the present invention.
[0025] FIG. 4E depicts an exploded view of the APL in accordance with the present invention.
[0026] FIG. 4F depicts graphically the damping characteristics of the APL of FIG. 4A ;
[0027] FIG. 4G depicts the theoretical modes of operation of the APL of FIG. 4A ;
[0028] FIG. 4H depicts graphically the actual modes of operation of the APL of FIG. 4A ;
[0029] FIG. 5A depicts an active control flap operating in the high-lift mode; FIG. 5B depicts an active control flap operating in the servo-tab mode;
[0030] FIG. 5C depicts an active control flap in accordance with the present invention;
[0031] FIG. 5D depicts a side view of the active control flap of FIG. 5C with the piezoelectric actuators in the “off” and “on” positions;
[0032] FIG. 5E depicts the skeleton and frame to which the active control flap of FIG. 5C is attached;
[0033] FIG. 5F depicts a fully assembled rotor with the active control flap of FIG. 5C ;
[0034] FIG. 6A depicts the fan plot for a helicopter blade and the effect of pitch link stiffness on torsional mode frequency;
[0035] FIG. 6B depicts an experimental demonstration of centrifugal tests to show the reduction of torsional stiffness via altering the resultant stiffness of the pitch link.
[0036] FIG. 7 is a block diagram depicting the control system of the hybrid device of the present invention;
[0037] FIG. 8 depicts a flow chart detailing the control steps performed by the control computer of FIG. 7 ;
DESCRIPTION OF PREFERRED EMBODIMENTS
(A) Hybrid Device—Overview
[0038] The present invention employs, at least in selected embodiment, the simultaneous application of any type of structural control and flow control device on each individual blade. For the purposes of describing the invention, a specific example of employing an Active Pitch Link (APL) for structural control and Actively Controlled Flap (ACF) for flow control will be presented. However, it should be appreciated, that the invention is not meant to be limited to this embodiment. The general principle of combining these two devices in a “hybrid system” can be extended to any other combination of structural and flow control devices.
[0039] Referring to FIG. 1A , the structural control is realized using an Active Pitch Link (APL) 100 , which replaces the conventional pitch link on the rotor hub ( 102 ). APL 100 is capable of changing the torsional stiffness of the rotor blade 104 .
[0040] The flow control is realized via an Actively Controlled Flap (ACF) 106 , located at the trailing edge of rotor blade 104 , closer towards the tip.
[0041] The frequency at which these two mechanisms operate is important. Both are able to actuate at the frequencies typical of Individual Blade Control (IBC), i.e. between (N−1)/rev and (N+1)/rev, where N represents the number of rotor blades 104 , i.e. for a 4-bladed rotor, both systems should have the capability to operate at the frequency of 3 to 5 actuations per revolution.
[0042] The two systems are connected to a controller 108 located on the top of rotor hub 102 , which dictates the combined operation of the two systems with the goal of minimizing vibrations. As depicted in FIG. 1B , the entire system is equipped with preferably eight (8) sensors 110 measuring vibration. Sensors 110 include a strain gauge, two hall sensors and three accelerometers mounted on rotor blade 104 and one hall sensor and two accelerometers mounted on APL 100 . Sensors 110 are linked to a computer in controller 108 , thus forming a closed-loop feedback control system consisting of controller 108 , APL 100 , ACF 106 and sensors 110 . The feedback control system will be discussed in more detail in relation to FIGS. 6 and 7 .
(B) Structural Control—Active Pitch Link (APL)
[0043] The main parts of a typical helicopter rotor hub 200 are depicted in FIG. 2A , highlighting the location of swashplate 210 as well as conventional pitch link 220 . It is the lower non-rotating disk of swashplate 210 , which is controlled by the pilot (not shown). When swashplate 210 is moved up-down or tilted to any direction, upper rotating disk 230 follows swashplate 210 and this motion is transferred to the rotor blade 240 via pitch link 220 . The purpose of the swashplate-pitch link system is to change the pitch angle θ of rotor blade 240 and thereby the magnitude and tilt of the resultant thrust force generated by rotor hub 200 . The pitch angle θ of rotor blade 240 can be changed either collectively (via an up-down motion of swashplate 210 (as depicted in FIG. 2B ) or cyclically via tilting of swashplate 210 (as depicted in FIG. 2C or in any combination of both. Each rotor blade 240 is connected to swashplate 210 via an associated pitch link 220 and pitch horn 250 . Pitch horn 250 is essentially the moment arm of pitch link 220 , allowing the rotation (“pitching”) of rotor blade 240 along its longitudinal (spanwise) axis. Changing the stiffness of rotor blade 240 at the root requires some form of active control system located at the root of rotor blade 240 , either directly at the root section of rotor blade 240 or indirectly on rotor hub 200 .
Active Pitch Link—Operating Principle
[0044] The Active Pitch Link (APL) of the present invention, at least in some embodiments, is a piezoelectric actuator-based device for controlling the blade stiffness at the root. The APL replaces conventional pitch link 220 on rotor hub 200 . Thus, its primary purpose is to control the pitch angle of rotor blade 240 in a semi-active way. The term semi-active control is used since the APL utilizes the concept of a Smart Spring as described in U.S. Pat. No. 5,973,440 entitled “Structural Component Having Means for Actively Varying its Stiffness to Control Vibrations”, issued Oct. 26, 1999 to Nitzsche et al. which is incorporated by reference herein. The described Smart Spring allows a user to control the displacement of a device in one direction only—the direction in which the load acts on the device. A fully-active control system would allow displacements in both directions, i.e. also in the direction opposite to the force acting on the device.
[0045] The operational principle of a generic Smart Spring is shown in FIG. 3A . Two springs, k 1 and k 2 have their ends attached to opposing walls 300 and a pair of sleeves 310 , 312 that can slide one with respect to the other. An external (input) force F is applied to sleeve 312 . A stack of piezoelectric actuators 320 is inserted into sleeve 310 .
[0046] Referring to FIG. 3B , when the actuator is “OFF”, the sleeves 310 , 312 can move freely and the resulting horizontal displacement (output) is δ max =F/k 2 . Spring k 2 is designed to be the “primary” load path of the APL. Referring to FIG. 3C , when the actuator is turned “ON”, sleeve 310 , under the action of the stack of piezoelectric actuators 320 , yields and applies on sleeve 312 a resultant normal force, N.
[0047] A friction force, μN is induced by the contact between the surfaces of sleeves 310 , 312 . If this friction force is sufficiently large and sleeves 310 , 312 are forced into motion together, springs k 1 and k 2 act in series and a smaller horizontal output displacement δ min =F/(k 1 +k 2 ) is obtained because the stiffness experienced by the input force rises from the system's original k 2 to k 1 +k 2 . Spring k 1 is driven by the resultant friction force μN applied by the sleeve 310 on sleeve 312 , which is controlled by the external electrical stimulus (control input) to the stack of piezoelectric actuators 320 . Spring k 1 is called the. “secondary” path of the APL.
[0048] Thus, the horizontal output displacement of the system under the input force F varies between the referred two extremes, F/(k 1 +k 2 )≦δ≦F/k 2 and the total load is distributed between the primary and the secondary load paths.
[0049] The APL system also changes its apparent mass because the stack of piezoelectric actuators 320 and sleeve 310 have inertial properties. However, this effect can be disregarded if the overall system is “stiffness dominated” (i.e., the harmonic disturbance force has a frequency much lower than the internal resonance frequencies of the APL). The dry friction between sleeves 310 , 312 also creates coulomb damping, which cannot be neglected. The latter adds an important stabilizing effect to the system. Since the APL actively changes both its apparent mass and stiffness and also its internal damping, it is called an “impedance control” device.
[0050] As discussed above, within the context of helicopter applications, the active pitch link (APL) replaces conventional pitch link 220 . Thus, rotor blade 240 and the APL become an integral system, which can control the twist impedance of rotor blade 240 in real time, by targeting the 1st torsional mode of rotor blade 240 . However, because of the inherent coupling between blade modes (i.e. when a blade is twisted, it will generate more lift, i.e. it will bend/flap up and as a result of this motion it will generate lead-lag motion too), when the torsional mode is controlled, all modes are controlled.
Active Pitch Link—Design
[0051] Referring to FIG. 4A , although the APL 400 of the present invention uses the Smart Spring concept, its internal configuration is significantly altered to facilitate a feature very important for aerospace applications: fail safe design. Fail safe design means that when a power failure or failure of piezoelectric actuator 410 occurs, APL 400 returns to the original “conventional pitch link” mode. In order to fulfill this fail safe design requirement, springs k 1 and k 2 are incorporated in parallel rather than in series (as in FIG. 3A ). Using this configuration, the overall system stiffness can be varied between k 1 (“soft” link) and k 2 (“solid” link), instead of the ranges of k 2 and k 1 +k 2 .
[0052] The main parts and operation of the APL 400 are arranged in the following configuration. In the default position i.e. when piezoelectric actuator 410 is OFF, a preload spring 420 pushes a friction pad 430 to a pair of solid links 440 a and 440 b . The force generated by preload spring 420 is such so that the friction force between friction pad 430 and solid links 440 a , 440 b is larger than the overall vertical force acting on APL 400 . Thus, when piezoelectric actuator 410 is OFF, all of the load will be transferred from a top plate 450 to a bottom plate 460 via load path consisting of solid link 440 a , friction pad 430 and solid link 440 b.
[0053] When piezoelectric actuator 410 is ON, friction pad 430 is pushed away from the solid links 440 a , 440 b and, when the two surfaces disengage, the entire load is transferred from top plate 450 to bottom plate 460 via “soft” spring k 1 .
[0054] An intermediate mode of operation, called transitional mode, can also be generated. This occurs when piezoelectric actuator 410 is only partially activated (i.e. when the actuation power is somewhere between zero and the maximum voltage). In this case, sliding friction will occur between friction pad 430 and solid links 440 a , 440 b , thus initiating the “energy extraction” operational mode, in which vibration is reduced by extracting energy from the system via sliding friction and heat.
[0055] The operational principle of APL 400 are illustrated in FIGS. 4B and 4C which depict the load paths when the actuator is switched ON and OFF.
[0056] A more detailed depiction of APL 400 is provided in FIGS. 4D and 4E . Here, the two springs k 1 , k 2 shown previously in the schematic diagram of FIG. 4A are arranged in a concentric fashion, i.e. solid link k 2 461 slides into the soft link spring k 1 462 . Such arrangement enhances the compactness of the design, which is important because of the space limitations on a rotor hub.
[0057] The two cylindrical piezoelectric actuators 464 are held in a holder assembly 466 , including friction pad 468 , preload springs 470 , shoulder bolt 472 , load cell 474 and a pair of set screws 476 .
[0058] Piezoelectric actuators 464 are off-the-shelf units from Piezomechanik Gmbh, capable of generating 1800 N block force or 60μ of displacement. Friction pad 468 is made out of brass, an effective material from friction point of view. The preload spring 470 is realized via a set of wave disc springs, which offer modularity (their number can be varied) as well as compactness. The amount of preload force can be adjusted via the number of wave disc springs applied as well as via the 2 set screws 476 . The resultant force acting on the friction pad (i.e. the sum of the preload spring force and the actuation force) is monitored via load cell 474 . Washers 478 , 480 , spacer 482 , screw 484 and nuts 486 and 488 all serve to hold the whole holder assembly together.
[0059] There are two discs 490 mounted on the top and bottom of APL 400 which hold accelerometers 492 , measuring both the vibratory loads as well as the relative displacement of the upper and lower swivel joints 494 . The top swivel joint 494 is left threaded and connects to the pitch horn of the rotor blade, whereas the lower swivel joint 494 is right-threaded and connects to the swashplate. Nuts 495 counter swivel joints 494 and thus serve to adjust the length of APL 400 .
[0060] Custom screw 496 serves to connect shoulder bolt 472 to solid link 461 . This is required to ensure that the friction force generated by piezoelectric actuators 464 is independent of the centrifugal loads, which should act from the load cell 474 towards the piezoelectric actuators 464 .
[0061] In addition to accelerometers 492 , the performance of APL 400 can also be monitored via a built-in Hall sensor 498 . Hall sensor 498 , mounted on soft spring link 462 , is paired up with a permanent magnet 499 , mounted on friction pad 468 . As these two move relative to each other, the electrical signal in the Hall sensor 498 changes and this can be related to the displacement between the two parts. The exact location of the permanent magnet 499 is adjustable since it is threaded at the bottom.
[0062] The APL depicted in FIGS. 4D and 4E operates as follows. As a default, the piezoelectric actuators 464 are OFF and preload spring 470 pushes friction pad 468 to the side of soft link spring 462 . The preload force has to be set in a way so that the default friction force is large enough to overcome the vertical force acting on APL 400 . Thus, solid link 461 and the top of soft spring link 462 become locked via the friction pad 468 (i.e. they cannot move relative to each other) and the load acting on APL 400 will be transferred from top to bottom via the following path: top swivel joint 494 —top of soft spring link 462 —friction pad 468 (link via friction)—custom shoulder bolt 472 —solid link 461 (connection via screw 496 )—bottom swivel joint 494 .
[0063] When the piezoelectric actuators are ON, friction pad 468 slides on custom shoulder bolt 472 and disengages the friction pad 468 from the soft spring link 462 . Thus, soft spring link 462 and solid link 461 can move relative to each other since there is no link (via friction) between them. As a result, all vertical load acting on APL 400 will be transferred via the soft link spring 462 through the following load path: top swivel joint 494 —soft spring link 462 —bottom of solid link 461 (connection via thread)—bottom swivel joint 494 .
[0064] When the actuator is OFF, APL 400 operates in the solid link mode, thus providing a Fail Safe design.
[0065] The advantages of APL 400 of the present invention are numerous and include:
(a) piezoelectric actuator 410 is used to generate friction force instead of acting against the principal force, thus requiring significantly lower power consumption (3-5% of Active Twist Rotor); (b) APL 400 incorporates a fail safe design such that when a power failure or failure of piezoelectric actuator 410 occurs, loads are transferred via spring k 2 representing the “solid link”; (c) the friction force generated through piezoelectric actuator 410 is independent of centrifugal loads. The system does not therefore lock purely from centrifugal loads; (d) the system provides adjustable resultant system stiffness i.e. by careful adjustment of the actuator voltage, sliding friction can be generated between springs k 1 and k 2 . The sliding friction allows adjustment of the resultant system stiffness anywhere between k 1 and k 2 as depicted in FIGS. 4F to 4H ; and (e) the system allows for self-compensation due to wear i.e. if the damping characteristics of APL 400 change in time due to the wear of contacting parts or temperature increase, the control algorithm (discussed in relation to FIG. 8 ) is able to self-compensate for these changes.
(C) Flow Control—Actively Controlled Flap (ACF)
[0071] As will be understood by a skilled workman, an Actively Controlled Flap (ACF) can work in two modes: either as a) a high-lift device or b) as an aeroelastic servo-tab. As depicted in FIG. 5A , the high lift device mode occurs when the blade behaves as a rigid structure, i.e. when the torsional stiffness of the rotor blade is very high. In this case, the local lift of the blade section is increased when the flap is deflected down.
[0072] As depicted in FIG. 5B ), the aeroelastic servo-tab mode occurs when the blade behaves as an elastic structure, i.e. when the torsional stiffness of the blade is too low. In this case, the “soft” blade section rotates as a reaction to the flap deflection, i.e. the local lift of the blade section will increase when the flap is deflected upwards, in the opposite direction than before. However, this second mode can ultimately yield much higher overall blade lift than the first mode, because the angle of attack of the entire blade is increased in the servo-tab mode. In other words, if the blade is made “soft” enough in torsion, it can be essentially twisted up/down by activating the flap up/down, respectively.
[0073] It has been shown in the prior art that usually the servo-elastic tab mode is more effective for controlling vibration. Therefore, the operation of the present invention incorporates an Actively Controlled Flap (AOF) tailored to produce upward deflections only.
[0074] The design of the ACF of the present invention is depicted in FIG. 5C . The ACF mechanism produces 4 degrees of deflection up (only) at a frequency of at least (N+1)/rev, where N is the number of rotor blades coupled to the rotor hub.
[0075] The proposed ACF 500 shown in FIG. 5C is driven by two piezoelectric actuators 505 which can operate at a frequency of up to 200 Hz. Hence, the system is capable of producing flap deflections corresponding to 8/rev for the worst case scenario of a scaled rotor with 1,555 RPM=25 Hz, i.e. well above the required (N+1)/rev (i.e. 5/rev for a 4-bladed rotor). The system is also capable of producing 4 degrees of deflection in the upward direction only.
[0076] As depicted in FIGS. 5C and 5D , the basic principle of ACF 500 is that a sliding rod 510 connected to the actuators 505 slides back and forth. The rod end is connected to a wedge 515 which then slides on a moment arm 520 linked to the flap 525 via a hinge point 530 . As piezoelectric actuators 505 are activated, they increase their length and as a result sliding rod 510 moves forward (ΔX). At the same time, moment arm 520 moves down, thus rotating flap 525 up. Wedge 515 and moment arm 520 each contains a magnet 535 , 540 of opposite poles which create a sliding link between the two parts. Magnets 535 , 540 are sized in a way so that the two parts of moment arm 520 and sliding rod 510 do not lock. Note, however, that because helicopter blades typically operate at positive angles of attack, the aerodynamic force acting on the flap will always help to produce the upward deflection, whereas wedge 515 moving towards the trailing edge will push flap 525 down.
[0077] The flap system shown in FIG. 5C is attached to rotor blade 555 shown in FIGS. 5E and 5F via the attachment points 545 through a skeleton 550 (See FIG. 5E ). Skeleton 550 is a removable part of rotor blade 555 which, during assembly, is slid into rotor blade 555 from the tip end. Skeleton 550 is a lightweight structure machined out of Titanium and optimized to bear stresses arising from the centrifugal loads of ACF 500 . ACF 500 slides into frame 560 , which is glued from inside to the skin of rotor blade 555 . Frame 560 features a nylon guiding rail for skeleton 550 . The two parts are connected to each other via a pin 565 , which is again sized to bear the resultant centrifugal loads from skeleton 550 and ACF 500 . The whole blade assembly is shown in FIG. 5F .
(D) Operation of Hybrid Device
[0078] It has been shown in the prior art that vibration on helicopters can be reduced relatively successfully by imposing blade pitch angle changes of about 1 degree at a frequency ranging between (N−1)/rev to (N+1)/rev. It is for this reason that an Actively Controlled Flap (ACF) is preferred to be operated as an aeroelastic servo-tab instead of a high-lift device. Achieving 1 degree pitch angle change, however, is at the limit of most flow control devices, such as the Active Twist Rotor (ATR) or Actively Controlled Flap (ACF). Larger pitch angle changes would lead to more significant reductions of vibration. The present invention allows the pitch angle change imposed by a flow control device to be improved by combining the flow control device with a structural control device. The structural control device serves to reduce the torsional stiffness of the blade whenever the flow control device is activated. More specifically, the blades are made instantaneously “softer” in torsion (twist) and thus the flow control device imposes larger pitch angles when activated.
[0079] This is the basic principle of the present invention, and a specific example would combine the Active Pitch Link (APL) (capable of controlling blade torsional stiffness) with the Actively Controlled Flap (ACF) (in the aeroelastic servo-tab mode) to create a “hybrid” control system.
[0080] The first condition of the hybrid control system is the careful selection of the stiffness of secondary “soft mode” spring k 1 of APL 400 . This value is selected in such a way that the natural frequency of rotor blade 240 in torsion, which is linked directly to torsional stiffness, (typically in the range of 6/rev) is brought down to the actuation frequency of the flow control device, APL 400 in the specific case of this invention (3/rev to 5/rev). The selection procedure of the soft mode spring stiffness is depicted in FIG. 6A . On the left hand side, the fan plot of a typical helicopter blade is shown, illustrating that the natural frequency in torsion occurs at about 6/rev frequency. On the right hand side, a graph showing the result of a sensitivity study is shown. It depicts the variation in natural frequency in torsion with the resultant pitch link stiffness of rotor blade 240 . If, for example, the torsional mode of rotor blade 240 is to be brought down to 3/rev frequency, the stiffness of soft mode spring k 1 should be 180 kN/m according to the graph. Using this method, when the ACF is activated at 3/rev frequency and at the same time the APL is also activated bringing down the torsional frequency of rotor blade 240 to 3/rev, rotor blade 240 will resonate in torsion and thus larger twist angles can be achieved.
[0081] FIG. 6B shows an experimental demonstration of the above claim from centrifugal tests. Note that for these tests a different blade was used than that described in the above computational studies. This meant that the “Soft Link” mode was expected to be achieved at a different spring stiffness than in the computational results shown above. Various spring stiffnesses were tested, ranging from a practically infinite value (k 5 ˜2,000 kN/m), representing the “Solid Link” mode of the APL, to a very low one (k 1 =10.9 kN/m) representing the “Soft Link” mode. Intermediate spring values were also considered to represent the transitional mode, i.e., k 4 =160.0 kN/m, k 3 =82.7 kN/m. From the fan plots, it is evident that the first torsional mode is indeed affected by the variation of the resultant pitch link stiffness at all rotational speeds. As expected, the torsional stiffness decreases as the APL becomes “softer”. The magnitude of the change is viewed relatively small, which would call for even lower APL stiffness in future iterations. However, the concept of reducing torsional stiffness via altering the resultant stiffness of the pitch link is successfully demonstrated in these experiments.
[0082] A block diagram of the “hybrid” control system is depicted in FIG. 7 . As highlighted in the figure, there is one central control computer 710 in the system, located preferably on the top of rotor hub 102 (See FIG. 1A ). Control Computer 710 serves all N blades. In order to realize the Individual Blade Control (IBC) integral to the present invention, each rotor blade 104 (See FIG. 1A ) has to be equipped with its own individual control system, i.e. each rotor blade 104 includes a structural control device (e.g. APL 400 ) 720 and a flow control device (e.g. ACF 500 ) 730 i.e. structural control device 720 and flow control device 730 will occur N times on helicopter rotor hub 102 . As shown in the figure, the control reference parameter (IN) 740 is the desired level of vibration. The actual level of vibration is measured via the eight (8) sensors 750 located on each rotor blade 104 (See element 110 in FIG. 1B ). Sensors 750 , along with three (3) accelerometers 760 located on the rotor shaft (not shown in the FIGS. 1A and 1B ) provide a feedback signal to control computer 710 , which then determines the optimum strategy for minimizing vibration and provides a control signal to structural control device 720 and flow control device 730 .
[0083] FIG. 8 depicts a flow chart detailing the control steps performed by control computer 710 of FIG. 7 . First, vibration data is received from sensors 110 at step 805 . This data, along with a certain portion of the time history of previous data, are analyzed via Fourier transformation at step 810 to determine the dominant vibration frequency (f VIB ) and vibration amplitude (P VIB ).
[0084] Following this, the type of control strategy (i.e. “ACF only”, “APL only” or “hybrid” control) is determined at steps 820 , 830 or 840 based on either the manual input of the pilot/operator or a database of experimental tests, in which the various control strategies have been linked to certain vibration levels.
[0085] Starting from the simplest control strategy, if the “ACF only” method is selected at step 820 , then at step 825 the flap actuation frequency and amplitude is set based on the transfer functions obtained from experiment/flight tests. Control voltage U ACF applied to the piezoelectric actuators will determine the amplitude of flap deflection. This value can be linked to the vibration frequency (f VIB ) and amplitude (P VIB ) and should be set between 0 V and 150 V for the particular design of ACF 106 (see FIG. 1A ) presented herein. The frequency of actuation can then be linked solely to the frequency of vibration and it should be between (N−1)/rev to (N+1)/rev frequency for best results. APL 100 (See FIG. 1A ) is idle in this case, with the solid link mode being functional.
[0086] If the “APL only” method is selected at step 830 , then at step 835 the APL actuation frequency and amplitude will be set based on the transfer functions obtained from experiment/flight tests. Control voltage U APL , however, will not be linked this time to the amplitude of actuation, but to the torsional frequency of rotor blade 104 (see FIG. 1A ). As has been shown in experiment (see FIG. 4H ), the resultant stiffness of APL 100 can be set to any value between k 1 and k 2 by setting U APL between 60 V and 120 V. When an intermediate value is set, APL 100 is in the transitional mode and it extracts energy from the system via sliding friction. This mode of operation is called the “energy extraction mode” and APL 100 is most efficient in this mode when applied on its own (without any Flow Control device) Since the stiffness of APL 100 is linked to the blade resonance frequency in torsion, the blade frequency can essentially be set to any desired value by activating APL 100 . The choice of the desired blade torsional frequency, and thus of U APL , will be driven by the frequency of vibration (f VIB ). The frequency of actuation will also be driven by the frequency of vibration (f VIB ). Note that in this case ACF 106 is idle.
[0087] Finally, if the hybrid control method is selected at step 840 , both ACF 106 and APL 100 are operational at the same time. First, the ACF operational mode is selected at step 850 based on pilot input or a database, in which vibration levels have been linked to the choice of operational mode. When the Servo Flap mode is selected, then first the ACF actuation parameters (frequency f ACF and amplitude U ACF ) are determined at step 860 from the transfer functions from experiment, similar to the “ACF only” mode described above. Next, at step 865 , phase angle φ is determined based on experience from tests. The phase angle determines the delay between forcing and response. It is known to be 90 deg at the resonance frequency, whereas it decreases to 0 deg below the resonance frequency and increases to 180 deg above the resonance frequency. The phase angle will dictate that when (in terms of rotor azimuth angle) APL 100 should be activated relative to the actuation of ACF 106 already determined at step 860 . Once the phase angle is known, the APL frequency (f APL ) and control voltage (U APL ) can be determined. Note that in contrast to the “APL only” configuration, these two parameters depend not only on the vibration frequency (f VIB ) but also on phase angle (φ) and the ACF frequency (f ACF ) as well, as shown in step 880 . The method of determining the control parameters for the High-Lift device mode, i.e. steps 870 and 875 , is analogous to the above description, with the difference that f ACF , U ACF and φ are determined from the transfer function for the high-lift flap mode.
[0088] The outputs from control computer 710 are the actuation parameters for the Flow Control (i.e. ACF 106 ) and Structural Control (i.e. APL 100 ) systems: these are sent to the control systems at step 890 . Note that the feedback loop between the outputs and the inputs is realized outside of control computer 710 as shown in FIG. 7 .
[0089] Thus, in selected embodiments, the Active Pitch Link may serve as a backup system for a “swashplateless” helicopter rotor controlled primarily by a Flow Control device (such as either an Actively Controlled Flap or Active Twist Rotor). Combining such Flow Control device with the Active Pitch Link can have at least two advantages:
a) the Active Pitch Link can improve the efficiency of the Flow Control device by lowering the torsional stiffness of the blade b) the Active Pitch Link can serve as a control system backup for the case that the Flow Control device fails. When the Flow Control device fails and is unable to serve its purpose as the primary means of rotor control, the blades (pitch angle) can still be controlled via the Active Pitch Link.
[0092] Although the hybrid control device of the present invention has been described in relation to rotor blades on a helicopter, it will be understood by those in the art that the invention may be applied to other devices employing blades in which vibration control is desired. For example, the hybrid control device may be applied to the blades of a wind turbine which behaves in a manner similar to a rotor blade such that vibration control would be beneficial. | Disclosed herein are control systems relating generally to the field of aerodynamics and more particularly to the control of vibration of rotor blades such as helicopter blades. Such systems involve devices for vibration control of each rotor blade, which incorporate control systems of the flow control type (e.g. actively controlled flap) and structural control type (e.g. active pitch link). Also disclosed are related methods of controlling vibration in a rotor blade, wherein the rotor blade is coupled to a rotor hub and has at least a torsional stiffness and a pitch angle associated therewith. | 8 |
FIELD OF THE INVENTION
The present invention relates to power combiner/dividers and, more particularly, to an improved structure having particular application as an N-way power combiner having N reject loads which are mounted to a common heat sink.
DESCRIPTION OF THE PRIOR ART
Signal combiners/dividers are known in the art. The U.S. Pat. to F. W. Iden No. 4,163,955 discloses a combiner/divider which is based on a well known Gysel device described by Ullrich H. Gysel of the Stanford Research Center in his paper entitled "A New N-Way Power Divider/Combiner Suitable for High Power Applications" which appeared in the proceedings of the 1975 M.T.T. Symposium, Palo Alto, Calif. The Gysel device is illustrated in FIG. 1 of the Iden patent. As a combiner, it has a plurality of input ports such as N input ports each adapted to be connected to an RF signal source and a common output port which is interconnected with the input ports by a plurality of N transmission lines. This Gysel device also includes a plurality of N load ports each connected to one of the N input ports by a transmission line. The N load ports are connected to a common point by another plurality of N transmission lines. An isolation load, sometimes referred to as a reject load, connects each of the N load ports to ground. A reject load serves to dissipate rejected power that takes place when the circuit becomes unbalanced such as upon deactivation as by failure or by unplugging one of the RF signal sources from one of the input ports.
It has been common practice in the art to provide heat sinks for dissipating the heat generated at the reject loads. If there are N reject loads there will be N heat sinks, each associated with one of the reject loads. For example, as will be brought hereinafter, in a 5-way combining system wherein each power amplifier provides an RF signal at 1 kw, the reject load corresponding to a deactivated RF signal source will need to dissipate approximately 800 watts. This power level will appear on any one of the five reject loads when its corresponding RF signal source is deactivated. The result is 800 watts of dissipation as a minimum must be provided at each reject load for a total of 4,000 watts of dissipation capability. Typically, such prior art implementations have included, for the example being presented, five heat sinks for the five reject loads with each heat sink being capable of dissipating 800 watts.
It has been determined that it is not necessary to employ N heat sinks in a system employing N reject loads in the example given above. Moreover, it has been determined that the total heat to be dissipated may be handled by a single heat sink which is sized and configured to provide a total heat dissipation capability to dissipate more than the maximum amount of heat required to be dissipated by any one of the N reject loads and less than N times that amount. In the example given above, as will be brought out hereinafter, the total dissipation required for a common heat sink will be on the order of 1,200 watts instead of the 4,000 watts if each of the five individual reject loads has an associated heat sink.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention, there is provided an N-way power combiner which includes a common output port and N input ports, each adapted to be connected to an RF input signal source for receiving therefrom an RF input signal which is to be combined with other RF input signals from a total of N signal sources to provide an output RF signal at the output port. N load ports are provided with each adapted to be connected to a reject load for purposes of dissipating power in the event that one or more of the RF input signal sources is deactivated. N first transmission lines are provided with each connected at one end to the common output port and each connected at its opposite end to a respective on of the N input ports. N second transmission lines respectively interconnect each of the input ports with one of the load ports. Also, N third transmission lines are provided and wherein each connects a respective one of the load ports with a common point. N reject loads are provided with each connected to a different one of the N load ports for dissipating power in the event that one or more of the RF input signal sources is deactivated. A common heat sink is coupled to all of the N reject ports with the heat sink being configured to provide a total heat dissipation capability to dissipate more than the maximum amount of heat required to be dissipated by any one of the N reject loads and less than N times that amount.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects of the invention will become more readily apparent from the following description of the preferred embodiment of the invention as taken in conjunction with the accompanying drawings which are a part hereof and wherein:
FIG. 1 is a schematic-block diagram illustration of one application of the present invention;
FIG. 2 is a schematic-block diagram illustration of an electrical circuit diagram of a combiner/divider constructed in accordance with the present invention;
FIG. 3 is a graphical illustration representative of impedance match with respect to frequency which is helpful in describing the operation of the circuit of FIG. 2;
FIG. 4 is a graphical illustration of power out to the antenna as a function of frequency and which is helpful in describing the operation of the circuit illustrated in FIG. 2;
FIG. 5 is a plan view of the electro-mechanical construction of a combiner/divider in accordance with the invention herein and wherein the view is taken generally along line 5--5 looking in the direction of the arrows in FIG. 6;
FIG. 6 is a top view partly in section taken generally along line 6--6 looking in the direction of the arrows in FIG. 5;
FIG. 7 is a plan view showing a first insulator board carrying coplanar metal traces thereon;
FIG. 8 is a view similar to that of FIG. 7, but showing another arrangement of coplanar metal traces mounted on a second insulator board; and
FIG. 9 is a view similar to that of FIGS. 7 and 8, but showing a third pattern of metal traces mounted on a third insulator board.
DESCRIPTION OF PREFERRED EMBODIMENT
Reference is now made to FIG. 1 which illustrates one application of the present invention in an RF transmitting system. Such a system employs an FM signal generator frequently referred to in the art as an FM exciter 10 together with an FM transmitter 12. The FM exciter 10 may produce a radio frequency signal in the FM range from 87.5 MHz to 108 MHz at a power level on the order of 25 watts. It is frequently desirable that the transmitted signal be boosted in power to, for example, five kilowatts. Solid state power amplifiers may be employed for increasing the power. There are limitations in the power handling capability of such amplifiers. It is for this reason that it is common to divide the signal to be amplified into several paths, each of which includes an RF power amplifier operating at a level of, for example, 1 kw. The amplified signals are then combined and transmitted as with an antenna. Such a system is illustrated in FIG. 1 wherein the output from the FM exciter 10 is supplied to an N-way signal divider 14 which then divides the signal into N paths applying each portion of the split signal to an RF power amplifier PA-1 through PA-N. In the example illustrated, each power amplifier may boost the power to 1 kw where N is equal to 5. The amplified signals are then supplied to an N-way signal combiner 16 to produce the final output signal at a power level on the order of 5 kw, which is then applied to the transmitting antenna 18. The signal divider 14 and the signal combiner 16 may each be constructed in the same manner. Moreover, the signal combiner/divider to be described herein can be employed as either a signal divider 14 or as a signal combiner 16. In the embodiment to be described, the signal combiner/divider is employed herein as a combiner 16 and will be referred to hereinafter as such.
Reference is now made to FIG. 2 which schematically illustrates the combiner/divider circuit constructed in accordance with the present invention. This is an N-way high power RF combiner/divider and, as illustrated in FIG. 2, it includes a common output/input port OI together with a plurality of N input/output ports IO-1 through IO-N, a like plurality of N load ports LP-1 through LP-N as well as a common point CP, to be described hereinafter.
The common output/input port OI is connected to each of the input/output ports IO-1 through IO-N by one of a plurality of transmission lines TL-1 through TL-N, each having a characteristic impedance of Z 1 and each having a length on the order of one quarter wavelength at the operating frequency of the combiner/divider. The input/output ports IO-1 through IO-N are interconnected with corresponding load ports LP-1 through LP-N by respective transmission lines TL'-1 through TL'-N, each exhibiting a characteristic impedance of Z 2 and each having a length on the order of one quarter wavelength at the operating frequency of the combiner/divider. Moreover, the load ports LP-1 through LP-N are respectively connected to the common point CP by transmission lines TL"-1 through TL"-N each exhibiting a characteristic impedance of Z 3 and wherein each has a length on the order of one quarter wavelength at the operating frequency of the combiner/divider. A reactance, in the form of a capacitor C s , interconnects the common point CP with electrical ground. It has been determined for one operating version of the invention herein that the capacitance of the capacitor C s may be on the order of 30.0 pf (picofarads).
The combiner/divider of FIG. 2 is employed herein as an N-way signal combiner 16 and as such the input/output ports are utilized as input ports and the common output/input port is employed as an output port. The input to the combiner is taken from the power amplifiers PA-1 through PA-N which are shown as being directly plugged into the input/output ports IO-1 through IO-N. Also, the load is shown as a resistor R 0 connected to the center connector of a coaxial cable 20 and thence to transmission lines TL-1 to TL-N.
The circuit further includes a plurality of reject loads RL-1 through RL-N respectively connected to the load ports LP-1 through LP-N. As will be appreciated in greater detail hereinafter, the reject loads RL-1 through RL-N are connected to a common-heat sink HS and which, in turn, is connected to electrical ground. Each of the reject loads RL-1 through RL-N includes a pair of resistors 30 and 32 connected together in parallel. Each of these resistors may be on the order of 100 ohms so that each reject load is on the order of 50 ohms.
The circuit described thus far in FIG. 2 differs from the Gysel circuit described in FIG. 1 of the Iden et al. U.S. Pat. No. 4,163,955 primarily in the following manner. The Gysel circuit has a floating center point and does not include a compensating reactance connecting the center point to ground as in FIG. 2 herein. Moreover, Gysel's circuit employs an output matching line which would be connected in FIG. 2 between what is shown as the output/input port OI to the resistor load R 0 . With these modifications being made to the Gysel circuit, improved performance has been accomplished. Specifically, the addition of capacitor C s along with the impedance of the reject loads RL-1 through RL-N and careful selection of the interconnecting impedances Z 1 , Z 2 , and Z 3 and their respective line lengths, normally about 0.25 wavelengths, form the basis of enhanced performance. This enhanced performance has resulted in increased bandwidth and improved input port return loss. This is presented in FIGS. 3 and 4 to be discussed below.
Reference is now made to FIG. 3 which is a graphical illustration of input impedance match in decibels (db) against frequency over the FM frequency band of from 87.5 MHz to 108 MHz. This graphical illustration depicts the operation of the Gysel circuit in the solid curve A against the operation of the circuit of FIG. 2 herein as curve B. The example is given with respect to a center frequency F c on the order of 98.0 MHz. This example picks an impedance match level on the order of -32 db as a point separating a good impedance match from a bad impedance match with a good impedance match being shown below the -32 db level. From this example, it is seen that the Gysel circuit has a good impedance match over a relatively narrow bandwidth from frequency Fl to frequency F2, such as from approximately 90 MHz to 106 MHz. Using the same example, the circuit of FIG. 2 provides a good impedance match over a wider bandwidth, such as the entire FM range from 87.5 MHz to 108 MHz, as is seen from curve B. At the center frequency F c , curve B shows a performance of approximately -38 db return loss as opposed to the Gysel circuit's return loss of -50 db on curve A. However, curve B does show that acceptable performance is achieved with the circuit of FIG. 2 for a substantially wider frequency band.
Reference is now made to FIG. 4 which shows two curves C and D respectively representing the operation of the Gysel circuit and the circuit of FIG. 2 herein with respect to power out to the antenna over the frequency band from 87.5 MHz to 108 MHz. From this curve, it is seen that the maximum power out to the antenna for both circuits takes place at the center frequency F c with the performance decaying somewhat at the outer ends of the frequency band. The performance of the circuit in accordance with FIG. 2, as shown by the dotted lines of curve D, is better in terms of power out to the antenna at the ends of the frequency band.
Layered Implementation
As will be brought out in greater detail hereinafter with respect to FIGS. 5 through 9, the combiner/divider of FIG. 2 is preferably implemented herein as a compact layered assembly employing suspended stripline techniques with an air gap above and below the stripline substrate for high power capability. The construction features an integral circuit matched reject load assembly for high port-to-port isolation. The system is essentially structured as a flat box permitting N RF power amplifiers (or modules) to be plugged directly into the assembly without the need for interconnecting coaxial cables as is common in the prior art. It is typical in the prior art that coaxial cables are employed to connect a combiner to a plurality of RF power amplifiers (or modules) as well as to a plurality of reject loads. The implementation of the circuit of FIG. 2 provides direct plug in of the power amplifiers PA-1 through PA-N to the input/output ports IO-1 through IO-N as well as an integral connection between the reject loads RL-1 through RL-N with the load ports LP-1 through LP-N.
The layered assembly herein is a three dimensional structure that allows several degrees of freedom in selecting the interlayer stripline impedances for best optimization of combiner parameters. The three dimensional approach employed herein permits stacking various stripline sections corresponding, for example, with layers 1, 2 and 3 of FIG. 2, with these layers being over and under each other with interconnecting points penetrating several layers as required. The stacked arrangement leads to a compact high power assembly that is particularly adaptable to the VHF and UHF frequency bands where the longer wavelengths normally lead to a large signal combining structure.
The layered assembly of the combiner/divider herein is illustrated in greater detail in FIGS. 5 through 9 to which attention is now directed. The structure is depicted in FIGS. 5 and 6 and it includes insulator boards 50, 52 and 54 and a fourth insulator board 56. Insulator boards 50, 52 and 54 are respectively illustrated in FIGS. 7, 8 and 9, to be discussed hereinafter. Each insulator board corresponds to one of the layers referred to in FIG. 2. Thus, insulator boards 50, 52 and 54 respectively correspond with layers 1, 2 and 3. Insulator board 56 may be considered as corresponding with a layer 4 and which serves to connect the reject loads RL-1 through RL-N to the layered assembly, as will be appreciated hereinafter.
In addition to the insulator boards 50, 52, 54 and 56, the layered assembly (FIG. 6) also includes metal sheets or layers 60, 62, 64 and 66 which serve as ground planes located above and below respective insulator boards. Additionally, the base 68 of a heat sink 70, to be discussed in greater detail hereinafter, can serve as a ground plane along with plate 66 on either side of the insulator board 56. Each of the insulator boards carries a plurality of metal traces and these traces, in conjunction with the associated ground planes, define suspended striplines with interleaving air gaps between the supporting insulator boards and the over and under metal ground planes permitting high power operation with the inherent ventilation capability of a layered assembly Moreover, as will be brought out hereinafter, the layered suspended striplines can be accurately set to the correct optimized impedance levels by controlling the width of the metal traces as well as the spacing between the traces and tho associated over and under ground planes.
The input/output ports IO-1 through IO-N for receiving the power amplifier modules PA-1 through PA-N are illustrated in FIG. 5. As is shown in FIG. 6 with respect to port IO-1, each of these ports includes a conventional coaxial connector 80 mounted to the metal plate 60 for receiving a coaxial input from a power amplifier. The center conductor of each coaxial connector 80 is connected to a pin 82-1 which serves to electrically connect together one end of a transmission line on board 50 with one end of a transmission line on board 52. Spring finger clips 83 electrically and resiliently interconnect pin 82-1 with the transmission lines on boards 50 and 52. Since there are N input/output ports, there are N connecting pins 82-1 through 82-N for this function. Thus, connecting pins 82-1 through 82-N interconnect with the central conductor of the coaxial connectors 80-1 through 80-N, respectively, to make electrical contact with the appropriate transmission terminations at the input/output ports IO-1 through IO-N.
The various insulator boards and the metal ground planes are separated from each other by air gaps which, together with the width of the metal traces on the boards, determine the impedances of the transmission lines. The spacing between the layers may be controlled as with a stepped spacer 84 of which one is illustrated in FIG. 6. Preferably, several such spacers are employed for maintaining the appropriate spacing between the various insulator boards and ground planes.
As can be seen from FIG. 2, each of the reject loads RL-1 through RL-N is electrically connected to a respective one of the load ports LP-1 through LP-N. Each reject load RL-1 through RL-N has an associated electrical connecting pin 90-1 through 90-N. The pins electrically connect a reject load with an associated transmission line termination at the respective load ports LP-1 through LP-N. Thus, for example, at the load port LP-1, one end of a transmission line TL'-1 on layer 2 (insulator board 52) must be electrically interconnected with the corresponding termination end of transmission line TL"-1 which is located on layer 3 (insulator board 54). The electrical connecting pin 90-1 interconnects the reject load RL-1 with transmission line traces located on insulator boards 52 and 54 while being electrically spaced from the metal ground planes 64 and 66. Corresponding electrical connections are made at the other load ports LP-2 through LP-N.
Reference is now made to FIGS. 5 and 6 which illustrate the insulator board 56 which is mounted to the heat sink base 68 and which carries the reject loads RL-1 through RL-N. As is seen in FIGS. 2 and 5, each reject load, such as reject load RL-1, include resistors 30 and 32. One end of each resistor is electrically connected to ground through the base 68 of the heat sink HS. The other ends of the resistors 30 and 32 are respectively connected by metal foil traces 92-1 and 94-1 to the load port LP-1. The connecting pin 90-1 interconnects the metal foil traces 92-1 and 94-1 together as well as to the transmission line terminations at the load port LP-1. In a similar manner, metal foil traces 92-2 through 92-N and 94-2 through 94-N interconnect the resistors 30 and 32 of reject loads RL-2 through RL-N with the connecting pins 90-2 through 90-N.
Before describing the electro-mechanical features of the common output/input port OI and the common point CP which is connected by a capacitor C s to ground, attention is directed to FIGS. 7, 8 and 9, which respectively illustrate the insulator boards 50, 52 and 54, together with the metal traces thereon.
Turning now to FIG. 7, there is illustrated an insulator board 50 and which is incorporated in layer 1 of FIG. 2 with the insulator board having metal traces 100 thereon defining the patterns as illustrated in FIG. 7. These traces, together with associated ground planes define suspended striplines which are the preferred implementation of the transmission lines TL-1, TL-2, TL-3, TL-4 and TL-N. Each of these metal traces has a common termination at the output/input port OI where the traces are electrically interconnected with a metal foil patch 102. This metal foil patch is connected to the center conductor of a coaxial connector 110 to be described hereinafter. The other end of each metal foil trace serves as a transmission line termination at the input/output ports IO-1, IO-2, IO-3, IO-4, and IO-N. These terminations of the transmission lines TL-1 through TL-N are electrically connected to associated terminations of transmission lines TL'-1 through TL'-N of board 52 by electrical connecting pins 82-1 through 82-N.
Reference is now made to FIG. 8 which illustrates the insulator board 52 having a pattern of metal foil traces 111 thereon with each of these traces having a length on the order of one-quarter wave length at the operating frequency of the combiner/divider. Each of these traces has an input/output port termination and a load port termination. The input/output terminations are at ports IO-1 through IO-N. These terminations are interconnected with transmission lines TL-1 through TL-N on board 50 (FIG. 7) by the respective electrical connecting pins 82-1 through 82-N.
The terminations at the opposite ends of transmission lines TL'-1 through TL'-N are interconnected with corresponding terminations of transmission lines TL"-1 through TL"-N on insulator board 54 (FIG. 9) by means of respective electrical interconnecting pins 90-1 through 90-N.
Reference is now made to FIG. 9 which illustrates insulator board 54 and which carries a pattern of metal foil traces 120 which together with over and under ground planes define suspended striplines employed herein as transmission lines TL"-1 through TL"-N. These transmission lines have respective common ends electrically connected together with a foil patch 122, which serves as one plate of the capacitor C s at the common point CP (FIG. 2). The other end of each transmission line terminates at a respective one of the load ports LP-1 through LP-N. These terminations are electrically connected to the corresponding terminations of transmission lines TL'-1 through TL'-N by means of the electrical interconnecting pins 90-1 through 90-N, respectively. The capacitor C s is defined by the metal foil patch 122 together with the above and below ground planes 64 and 66 with the area of the patch and the spacing from the ground planes being adjusted to attain the capacitance desired.
The common output/input port OI is best illustrated in FIGS. 2 and 6 and serves to connect a common termination of the transmission lines TL-1 through TL-N with a center conductor of a coaxial cable. The coaxial cable connector 110 is of conventional design and includes a central upstanding copper pipe 113 which is carried by an insulator 115 and is electrically interconnected with the common metal foil patch 102 (FIG. 7) at the output/input port OI. The pipe 113 carries an extension known as a bullet 117 which is coaxially surrounded by an outer sleeve 119. Bullet 117 serves to make engagement, in a conventional manner, with the inner conductor of a coaxial cable and the outer sleeve 119 serves to make electrical contact with the outer conductor of a coaxial cable. Sleeve 119 is carried by and electrically connected to ground planes, such as the metal layers 62 and 66.
Reject Load and Heat Sink Assembly
The reject loads RL-1 through RL-N together with the heat sink 70 may be considered as an integral assembly which serves as a plug-in unit. Thus, the interconnecting electrical pins 90-1 through 90-N plug into the layered assembly such that the pins make electrical contact with the appropriate transmission line terminations at the load ports LP-1 through LP-N. In the example presented herein, N=5 and, consequently, there are five reject loads mounted on a combination of the insulator board 56 and the adjacent surface of heat sink base 68. Also attached to the heat sink base and extending in a direction away from the layered assembly is a plurality of aluminum fins 71 which serve to dissipate heat in a known manner.
Typically, in a multi-port combiner, each load port, is provided with a reject load. The reject load serves as a load for power that is being rejected when an imbalance takes place in the combiner, such as from deactivating one or more of the power amplifiers PA-1 through PA-N by either disconnecting the power amplifier or upon its failure. Since one never knows which load port will require cooling, it has been typical to design for the worst case situation for each port. Normally, this has meant that there are N heat sinks and excessive air for cooling to handle the N reject loads, such as reject loads RL-1 through RL-N in FIG. 2.
As will be brought out hereinafter, the present invention permits use of such a combiner with a common heat sink coupled to all of the N reject loads with the heat sink being configured to dissipate the heat resulting from the deactivation of more than one of N RF power amplifiers. This permits a single heat sink to be used for cooling the reject loads under all combinations of deactivating one or more of the power amplifiers. This will be more readily understood from the discussion that follows below.
It has been determined that the total dissipated power of an N-way zero phase combining system follows the formula presented below when one or more RF power amplifiers, such as amplifiers PA-1 through PA-N, are removed or deactivated. ##EQU1## where: Pd=total reject load dissipation in watts
Pm=RF amplifier output power in watts
n=total number of RF amplifiers
x=number of RF amplifiers deactivated
Assume that x=1 deactivated or removed power amplifiers in a system wherein n=5, defining a five-way combining system using power amplifiers each providing 1 kw power. In such case, the reject load corresponding to the deactivated power amplifier will dissipate 800 watts. Thus, for example, if power amplifier PA-2 has been deactivated or removed, then the reject load RL-2 corresponding to that amplifier will dissipate 800 watts. This power level may well appear on any one of the five reject loads RL-1 through RL-N when its corresponding RF power amplifier has been removed or deactivated. Consequently, 800 watts of dissipation must be provided at each reject load RL-1 through RL-N. If separate heat sinks are provided, one for each reject load, then with N=5, there will be five heat sinks, each providing 800 watts of dissipation for a total of 4,000 watts of dissipation capability. It is to be noted that in examining equation (1), the total system reject load dissipation for x=1, 2, 3, 4, and 5 is 800 watts, 1,200 watts, 1,200 watts, 800 watts, and 0 watts, respectively. This shows that a common integrated heat sink system for the reject loads need only have a dissipation capability of 1,200 watts instead of the 4,000 watts as would be required if five individual reject load heat sinks be provided Consequently, it is seen that a single heat sink need only have the capability of dissipating the heat that would be required if more than one (at least two) of the power amplifiers be deactivated, as by being unplugged or electrically inoperative.
The equation (1) presented hereinbefore has been derived for an ideal combining system where each power amplifier PA-1 through PA-N is delivering equal voltages V 1 , V 2 through V n to an ideal N-way combiner with the voltages being combined in phase The output voltage applied to a common load R L is the scaler sum of the individual input voltages. The derivation of the equation (1) follows below: ##EQU2## Then the output power for X inactive amplifiers in the system, taken as a ratio is: ##EQU3## Where P o ' is resulting output power due to X number of deactivated amplifiers. This leads to: ##EQU4## (Where R 1 is cancelled out) or simply, power reduction ratio: ##EQU5## where V n , V x cancels out by noting: V 1 =V 2 =. . . Vn=Vx Defining new terms for N-way, in-phase combiner with reject loads:
n=number of modules
x=number of deactivated modules
Pm=module power
Pd=total reject load dissipation
Under normal conditions: (All PA's active)
nPm=P.sub.t (total output power) (6)
For X number of deactivated modules use (5). ##EQU6## For total reject load dissipation:
(n-x)Pm=P.sub.A (power available after X deactivations) (8)
Then
P.sub.A -P'.sub.T =Pd (total reject load dissipation) (9)
substituting (8) into (9):
(n-x)Pm-P'.sub.T =Pd (10)
Substituting (7) into (10): ##EQU7## Expand and cancel n: ##EQU8## Rearranging ##EQU9##
Although the invention has been described in conjunction with a preferred embodiment, it is to be appreciated that various modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims. | An N-way power combiner includes a common output port and N input ports, each adapted to be connected to an RF input signal source. N load ports are provided with each being adapted to be connected to a reject load. N first transmission lines are provided with each connected at one end to the common output port and each connected at its opposite end to a respective one of the N input ports. N Second transmission lines respectively interconnect each of the input ports with one of the load ports. Also, N third transmission lines are provided and wherein each connects a respective one of the load ports with a common point. N reject loads are provided with each connected to a different one of the N load ports for dissipating power in the event that one or more of the RF input signal sources is deactivated. A common heat sink is coupled to all of the N reject ports with the heat sink being sized and configured to provide a total heat dissipation capability to dissipate more than the maximum amount of heat required to be dissipated by any one of the N reject loads and less than N times that amount. | 7 |
This application is a continuation-in-part of U.S. patent application Ser. No. 10/038,219, filed Jan. 3, 2002 which is incorporated in its entirety.
FIELD OF THE INVENTION
The present invention relates to a tufting machine with replaceable self-aligning gauge modules and is more particularly concerned with gauge modules with individually replaceable gauge elements which can be readily installed and removed.
BACKGROUND OF THE INVENTION
Tufting machines are built with precision so that the needles and loopers of the machine are accurately spaced from each other along the needle bar or looper bars. The loopers and needles must be spaced from each other so that the looper bills pass closely adjacent to the needles to engage and hold loops of yarns carried by the needles. When assembling a tufting apparatus, errors in positioning these gauge elements may accumulate as the work progresses. The present invention seeks to establish consistency with these parts across the width of the apparatus, to provide a tufting environment, suitable even for narrow gauge configurations. The present invention also addresses the problem of replacing individual gauge elements that become broken or damaged during tufting. In most modular designs, a broken gauge element requires discarding the entire modular block containing a set of about one to two dozen gauge elements. The present invention allows for quick and efficient replacement of individually damaged gauge elements.
The idea of replacing individual components of assemblies in tufting machines is not new. In the past, knife holder assemblies have been devised that allow for the replacement of individual knives. The knives were arranged in pre-assembled or modular fashion in a knife holder, each knife holder having a guide mechanism which enabled groups of knives, each group in a separate holder, to be positioned on a carrying member of a tufting machine and maintained in appropriate alignment. U.S. Pat. Nos. 4,608,934; 4,669,171; 4,691,646; and 4,693,191 illustrate such prior art knife holder assemblies in which parallel knives are disposed. These prior art knife holder assemblies are then disposed in transverse bars provided with guides for positioning the holders in appropriate positions on a tufting machine.
Needles have previously been individually secured in modular gauge blocks as shown in U.S. Pat. No. 4,170,949, and hooks and knives have also been individually secured in gauge parts mounting blocks as shown in U.S. Pat. No. 4,491,078. These designs have used individual clamping screws to hold each gauge element in place. These blocks were not mated with slots on the carrying members and were heavily machined. In addition, the clamping screws used in these gauge blocks have typically been flat ended and have relied upon the flat tip pushing directly against the gauge element to securely position those gauge elements. When the blocks are machined from relatively soft metals such as aluminum, there has been a tendency for the threads of the block to become worn and allow too much play for all of the screws to securely hold their corresponding gauge elements.
More recently attempts have been made to incorporate needles and loopers into replaceable modular blocks. U.S. Pat. Nos. RE37,108, 5,896,821, 5,295,450 illustrate such modular gauge assemblies in which the gauge elements are permanently embedded into the modular block. The block is attached to the guide bar with a single screw allowing for removal and replacement of the block. One shortcoming of these modular blocks is that when a single gauge element breaks the entire modular block must be discarded.
SUMMARY OF THE INVENTION
The present invention includes a modular gauge assembly that attaches to a gauge bar. The gauge bar has a plurality of positioning recesses that allows a detent on an individual modular block to be accurately positioned along the gauge bar. Each modular block typically includes a front surface, a pair of side surfaces opposed to each other, a rear surface opposite to the front surface, and a bottom surface.
A tongue, which may or may not be a part of the cast block extends from a rear or bottom surface of the modular block. The tongue includes a threaded hole which along with a securing screw serves to mount the block to a gauge bar. The threaded hole aligns with the gauge bar receiving hole when the tongue of the modular block is positioned properly with a recess on the gauge bar. When sufficiently tightened, the securing screw holds the modular block to the gauge bar.
At least the front surface of the block contains a plurality of spaced parallel slots so that gauge elements may be positioned in the slots with proper spacing. The proximal ends of the gauge elements may have apertures or channels recessed therein. In one embodiment of the present invention the proximal ends of the gauge elements are inserted into the block and secured there by a lateral pin that enters the block on one of the opposing side surfaces and passes through apertures on the proximal ends of the gauge elements. An alternative embodiment biases a lateral pin resting in a channel on the proximal ends of the gauge elements by tightening a securing bolt that is in communication with the lateral pin through an opening on the block. The preferred securing bolts have conical ends to exert a wedging or camming force against the lateral pin. In either case the gauge elements are secured by a lateral pin engaging the gauge elements. Individual gauge elements can be replaced by demounting the affected block, removing the lateral pin and removing a selected gauge element. After the selected gauge element is removed a new gauge element may be re-inserted into the proper vertical slot and secured by the lateral pin and securing bolt.
A plurality of modular blocks are arranged along the surface of the gauge bar and are vertically positioned on the gauge bar by a horizontal surface of the gauge bar or of a guide bar that passes through a guide bar channel on the gauge bar. The width of each block is substantially equal to the distance between the positioning recesses of the gauge bar so that the edges of the blocks abut one another and the blocks are laterally positioned.
In an alternative embodiment of the present invention each modular gauge assembly attaches to a gauge bar having a plurality of positioning recesses that allows the detent on the individual modular block to laterally position the block on the gauge bar. Each modular block typically includes a front surface, a pair of side surfaces opposed to each other, a rear surface opposite to the front surface, and opposing bottom and top surfaces. The rear surface contains a rectangular tab or detent that includes a threaded hole to receive a securing screw. The threaded hole aligns with the gauge bar receiving hole when the modular block is positioned properly on the gauge bar. When tightened, the securing screw holds the modular block securely to the gauge bar. A plurality of gauge holes extend from the bottom toward the top surface, in some cases passing through the modular block. Gauge elements with proximal ends adopted to be received within the gauge holes may be positioned with proper spacing in the block. Gauge elements that have the proximal end inserted into the block are securely positioned by pin-screws that enter the block below the tab on the rear surface. The pin-screws are positioned beneath the tab. In this fashion, the pin-screws can be accessed without removing the modular block from the gauge bar. When engaging rounded gauge elements such as tufting needles, the pin screws may advantageously have conical ends to hold the gauge elements by wedging or camming force.
Accordingly, it is an object of the present invention to provide a tufting machine where the gauge elements of the tufting machine are accurately positioned within a modular block assembly.
Another object of the present invention is to provide in a tufting machine, a system which can facilitate the rapid change over of one or more damaged gauge elements, reducing to a minimum the downtime of the tufting machine.
Another object of the present invention is to provide in a modular block assembly, a system which can facilitate the rapid change over of individual damaged gauge elements, reducing the cost of repairing broken gauge elements and removing the need to replace entire modular blocks when a single gauge element becomes damaged.
Other objects, features, and advantages of the present invention will become apparent from the following description when considered in conjunction with the accompanying drawing wherein like characters of reference designate corresponding parts throughout several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary perspective view of a modular block assembly with single looper modular blocks in place on a gauge bar.
FIG. 2 is an exploded perspective view of the modular block assembly of FIG. 1 with modular blocks removed from the gauge bar, and one looper modular block disassembled.
FIG. 3 is a perspective view of the rear surface of a modular block of FIG. 1 .
FIG. 4 is a fragmentary perspective view of a double looper modular block assembly with modular blocks in place on the gauge bar.
FIG. 5 is an exploded perspective view of the modular block assembly of FIG. 4, with modular blocks removed from the gauge bar and one block disassembled.
FIG. 6 is a fragmentary perspective view of a modular needle block assembly with modular blocks in place on a gauge bar.
FIG. 7 is an exploded fragmentary perspective view of the modular needle block assembly of FIG. 6 with the modular blocks removed from the gauge bar and one block disassembled.
FIG. 8 is a rear perspective view of a modular block of FIG. 6 .
FIG. 9 is an exploded perspective view of a modular assembly having a single row of loop-pile hooks held in place by a lateral pin and securing bolts.
FIG. 10A is an exploded view of a modular block having a double row of loop-pile hooks held in place by lateral pins and securing bolts.
FIG. 10B is a top perspective view of the relative positions of the gauge elements, lateral pins and securing bolts of FIG. 10A when mounted in the block.
FIG. 10C is a bottom perspective view of the relative positions of the gauge elements, lateral pins and securing bolts of FIG. 10A when mounted in the block.
FIG. 10D shows in isolation a side elevation view of the relative positions of a single gauge element, lateral pin and securing bolt when mounted in the block.
FIG. 11A is an exploded view of a modular block having cut-pile hooks with lateral pins, and securing bolts.
FIG. 11B is a side elevation view of the block of FIG. 11 A.
FIG. 11C is a side elevation view of the relative positions of the gauge elements, lateral pins and securing bolt of FIG. 11B when mounted in the block.
DETAILED DESCRIPTION
The present invention is designed for use in tufting machines of the type generally including a needle bar carrying one or more rows of longitudinally spaced needles that are supported and reciprocally driven by a plurality of push rods. In the tufting zone, the needles carry yarns which are driven through a backing fabric by the reciprocation of the needles. While penetrating the backing fabric, a plurality of longitudinally spaced hooks cooperate with the needles to seize loops of yarns and thereby form the face of a resulting fabric. In some cases the hooks will cooperate with knives to cut the loops of yarn seized on the hooks and thereby form a cut pile face for the fabric. The present invention is directed to modular units for holding loopers or hooks and for holding needles to facilitate their cooperation during the tufting process.
Referring in detail to FIG. 1, a modular block assembly 5 is illustrated having a single row of gauge elements 10 , in this case loopers, housed in a series of modular blocks 15 . The individual gauge elements 10 are fastened to each block 15 by a lateral pin 20 . As better illustrated in FIG. 2, the lateral pin 20 enters the modular block 15 at one of the opposing side surfaces 22 a, 22 b. The gauge bar 25 and guide bar 30 are used in concert to position the modular blocks 15 relative to one another. The guide bar 30 extends laterally through channel 35 substantially the entire length of the gauge bar 25 . The tab breaks 115 of the modular blocks 15 engage with guide bar 30 as shown in FIG. 3, to vertically align the individual blocks 15 in the modular block assembly 5 .
FIG. 2 illustrates a portion of the modular block assembly 5 with the blocks 15 detached from the gauge bar 25 . The gauge bar 25 has a plurality of vertical recesses 40 . The recesses 40 are crossed by lateral channel 35 so that guide bar 30 fits between the gauge bar 25 and the rear surfaces 45 of the modular blocks 15 . Guide bar 30 creates upper face 31 and lower face 32 which are normal to the side walls of recesses 40 . When tab breaks 115 of modular blocks 15 engage these faces 31 , 32 , the faces serve as restraining surfaces to hold blocks 15 in vertical alignment.
One modular block 15 in FIG. 2 is disassembled and removed from the gauge bar 25 to reveal spaced parallel slots 50 divided by vertical walls 51 located on the front surface 55 of the block for receiving the proximal ends 75 of the gauge elements 10 . The illustrated proximal ends 75 of the gauge elements 10 contain apertures such as pinholes 70 . When the gauge elements 10 are positioned in the modular block 15 the pinholes 70 align with apertures formed in side surfaces of the block such as pin opening 85 . Lateral pin 20 is then inserted through pin opening 85 in one of the opposing side surfaces 22 a, 22 b, and the pinholes 70 for each gauge element 10 to fasten the gauge elements 10 in block 15 .
In illustrated modular blocks 15 containing only a single row of gauge elements 10 , a tongue portion 60 extends from the rear surface 45 of the modular block 15 . The tongue 60 has an opening, preferably in the form of hole 90 , as shown in FIG. 3 . When the modular block 15 is positioned on the gauge bar 25 , threaded hole 90 aligns with another hole 100 located in a gauge bar recess 40 . Once a modular block 15 is positioned a securing screw 65 can be inserted through hole 90 and tightened into the hole 100 on the gauge bar 25 . A modular block 15 , once fixed in place by the securing screw 65 , is prevented from lateral and vertical movement. The screw 65 and side walls of vertical recesses 40 resist against horizontal movement while the screw 65 and faces 31 , 32 of the guide bar 30 resist against vertical movement. The fixed position of the blocks 15 insures that the gauge elements 10 remain properly aligned during the tufting process.
FIG. 3 shows the rear surface 45 of a modular block 15 having a single row of gauge elements 10 . On the rear surface 45 is a detent in the form of an elongated tab 110 extending vertically from the top 165 of the block to the bottom of the tongue portion 60 of the block. Tab 110 has a horizontal break 115 that engages with guide bar 30 to vertically position block 15 on the gauge bar 25 . The walls of break 115 are preferably substantially planar and parallel so that a part of the rectangular cross section of guide bar 30 closely fits within break 115 . The lower segment 120 of the tab contains the opening 90 where the securing screw 65 enters and attaches to a receiving hole 100 in the gauge bar 25 .
FIG. 4 illustrates a section of a modular block assembly 5 with three double gauge element modular blocks 130 mounted on the gauge bar 26 . Each modular block 130 contains two transverse gauge element rows 125 , the forward gauge elements 12 forming a first row 125 and rear gauge elements 11 forming a second row. Modular blocks 130 have two apertures such as pin openings 85 a, 85 b that are spaced apart on the side surfaces 22 a, 22 b of the block 130 . Unlike blocks 15 in FIG. 1, a portion of the double gauge modular blocks 130 rests on top of the gauge bar 26 to vertically position blocks 130 . This is accomplished by using a downwardly extending detent such as tongue 60 illustrated near the center of the bottom 135 of blocks 130 .
FIG. 5 shows an exploded view of modular block 130 containing two rows 125 of gauge elements 11 , 12 . The gauge bar 26 in FIG. 5 has a plurality of vertical recesses 40 . Vertical recesses 40 receive tongues 60 to horizontally position blocks 130 along the gauge bar 25 . Vertical positioning is accomplished by resting part of the bottom surface 135 of gauge blocks 130 on the top surface of gauge bar 25 . Modular block 130 in FIG. 5 is disassembled and removed from the gauge bar 26 to reveal the spaced parallel slots 50 a, 50 b located on the front 55 and rear surface 45 of the block 130 for receiving the proximal ends 77 , 78 of the front and rear gauge elements 12 , 11 .
The proximal ends 77 , 78 of the gauge elements 12 , 11 contain openings such as pin holes 71 , 72 which when positioned in slots 50 a, 50 b of modular block 130 align with pin openings 85 a or 85 b, respectively. The lateral pins 20 a, 20 b are inserted through the pin openings 85 a or 85 b on one of the opposing side surfaces 22 a, 22 b and through pin holes 71 , 72 in the proximal ends of each gauge element 11 , 12 to fasten the gauge elements 11 , 12 in the modular block 130 .
In the illustrated modular blocks 130 the tongue portion 60 of the modular block 130 extends centrally from the bottom surface 135 . Tongue 60 defines an opening (not shown). When modular blocks 130 are positioned on gauge bar 26 , this opening aligns with a threaded receiving hole 100 , located in vertical recesses 40 of gauge bar 26 . Once the modular block 130 is positioned a securing screw 65 can be inserted through the opening in tongue 60 and tightened into threaded receiving hole 100 . Modular blocks 130 , once fixed in place by securing screws 65 , are prevented from lateral movement by the securing screw 65 and interface of the detent against walls of vertical recesses. Similarly, modular blocks 130 are prevented from vertical movement by securing screw 65 and interface of bottom surface 135 against the top surface 26 a of gauge bar 26 . The fixed position of the block 130 insures that the gauge elements 11 , 12 remain properly aligned during the tufting process.
Referring now to FIG. 6, another aspect of the present invention depicts a section of a modular block assembly 5 having a row of gauge elements, in this case needles 13 , housed in clamping modular blocks 140 . FIG. 6 shows four clamping modular blocks 140 attached to gauge bar 27 . The clamping modular blocks 140 are positioned such that the lower portion 150 of the block 140 extends beneath the gauge bar 27 . This exposed lower portion 150 contains individual clamping elements, such as screw-pins 145 , shown in FIG. 7, that hold the gauge elements 13 in place in the block 140 . The gauge bar 27 has a horizontal shelf portion 27 a and a vertical portion 27 b which join to form an interior right angle into which the blocks 140 are positioned.
FIG. 7 illustrates a portion of a modular block assembly 5 with screw-pin modular blocks 140 detached from the gauge bar 27 and one block 140 disassembled. The gauge bar 27 has a plurality of vertical recesses 40 on the inner surface of vertical portion 27 b of the gauge bar 27 . As illustrated, the recesses 40 do not extend the entire height of the wall portion 27 b of the gauge bar 27 . Each recess 40 preferably contains a clearance hole 100 which receives a securing screw 65 to attach blocks 140 to the gauge bar 27 . The rear surfaces 45 of modular blocks 140 have a detent such as tab 160 with an opening, such as threaded hole 90 (shown in FIG. 8 ), positioned to align with holes 100 , located in the vertical recesses 40 of gauge bar 27 . Once a modular block 140 is positioned in the interior right angle between the shelf portion 27 a and wall portion 27 b, with tab 160 received in a vertical recess 40 , the securing screw 65 can be inserted through the corresponding hole 100 in the wall portion 27 b into the threaded hole 90 in the tab 160 and tightened to hold the modular block 140 in place. Once fixed in place by securing screw 65 , the modular block 140 is prevented from lateral movement by the action of the tab 160 fitting between the vertical walls of the vertical recess 40 , by the screw 65 . Vertical movement is restrained by action of the screw 65 and the interface of the top surface 165 of block 140 with the bottom of shelf portion 27 a of the gauge bar 27 . The fixed position of the block 140 insures that the gauge elements 10 remain properly aligned during the tufting process.
FIG. 7 also depicts a disassembled clamping modular block 140 thereby revealing the spaced parallel gauge element openings 155 which extend from the top surface 165 to the bottom surface 135 of the block 140 . Openings 155 need not extend completely to the top surface 165 for satisfactory operation, however, it is convenient for manufacture. The individual needles 13 are fastened to the block 140 by dedicated clamps such as screw-pins 145 that fix individual gauge elements 10 within the block 140 . Screw pins 145 enter the block 140 at the rear surface 45 of the block 140 on its lower portion 150 . When the block is attached to the gauge bar 27 the screw-pins 145 remain accessible so that individual gauge elements 10 can be removed and replaced.
FIG. 8 illustrates the top 165 and rear surface 45 of the block 140 . Gauge element openings 155 can be seen on the top surface 165 of the block 140 . A rectangular tab 160 for positioning the block 140 on the gauge bar 27 is located centrally on the rear surface 45 of the block 140 . The rectangular tab 160 defines the opening 90 which aligns with the holes 100 in vertical recesses 40 and with securing screw 65 fixes the block 140 to the gauge bar 27 . Openings 170 for screw pins 145 are located horizontally along the lower portion 150 of block 140 .
Referring now to FIG. 9, a preferred embodiment of the present invention depicts a modular block assembly 5 having a single row of gauge elements, in this case loop pile hooks 10 , housed in a single gauge modular block 15 . The modular block 15 may be mounted and attached to the gauge bar 25 with securing screw 65 extending through the block 15 into the gauge bar 25 . The gauge elements 10 are inserted in and removably secured to the block 15 by use of lateral pin 20 . The lateral pin 20 may be divided into two or more sections, or be formed of somewhat malleable material, to compensate for various differences in the heights of the gauging elements 10 .
Unlike the previous embodiments, the illustrated lateral pin 20 does not extend through openings in the gauge elements 10 , but merely abuts proximal ends of gauge elements 10 so that the gauge elements 10 are resting on the lateral pin 20 . The lateral pin 20 is then biased against the gauging elements 10 by a clamp such as securing bolt 38 received in threaded opening 39 on the top surface 165 of modular block 15 . Tightening securing bolts 38 biases the lateral pin 20 against the gauging elements 10 . In a preferred embodiment the lateral pin 20 is made of a soft metal such as brass so that when urged by the securing bolt 38 , the lateral pin 20 deforms slightly and compresses within channels 79 of individual gauge elements 10 . As a result of the clamp, the lateral pin 20 is held in place preventing lateral movement of the pin 20 into or out of the block 15 .
Due to differences in the width of the proximal ends 75 and channels 79 of the various gauge elements 10 , varying amounts of pressure are required along the length of pin 20 to sufficiently compress and restrain the gauge elements in a fixed position. Thus a preferred construction divides the pin 20 into segments to prevent the necessity of compressing a single pin 20 into all the gauge elements 10 .
This method of securing gauging elements to a block may also be employed for double gauge modular blocks 130 as seen in FIG. 10 A. Rear and forward gauging elements 11 and 12 are arranged in parallel transverse rows on block 130 . The rear row of gauging elements 11 is held in position by rear lateral pin 20 a. Pin 20 a is biased against the rear gauging elements 11 by securing bolts 38 a which are received by threaded openings 39 a. Likewise, the forward gauging elements 12 are held in place by forward lateral pin 20 b biased against the forward gauging elements 12 by securing bolts 38 b which are received by threaded openings 39 b.
In FIGS. 10B and 10C, the gauge elements 11 , 12 are shown with lateral pins 20 a, 20 b and securing bolts as they would be positioned in blocks 130 , however, the blocks are not shown. Of particular interest is the conical point 89 of securing bolts 38 a, 38 b. The conical points 89 are aligned alightly off center of lateral pins 20 a, 20 b, so that the side wall rather than the vertice of the conical point makes contact with the pins 20 a, 20 b. This causes a wedge like or camming effect to pressure pins 20 a, 20 b against gauge elements 11 , 12 . When securing bolts 38 a, 38 b utilize camming action rather than mere frontal clamping pressure as would typically be the case if the bolts had flat ends, the bolts 38 a, 38 b will continue to function even when wear and operating stresses have introduced some play between the threads of the bolts 38 a, 38 b and their openings 38 a, 39 b.
FIG. 10D shows a single securing bolt 38 a with conical point 89 applying camming type pressure against lateral pin 20 a which is engaged in channel 79 of rear gauge element 11 . The modular block 130 that would hold these components is not shown so that the interaction of the gauge element, lateral pin 20 a and securing bolt 38 a can be clearly illustrated.
An additional embodiment of the invention is illustrated in FIG. 11 A. The gauge elements, in this case cut-pile loopers 14 , 18 are shown removed from block 15 . When mounted in block 15 , the gauge elements 14 , 18 fit between lateral bracing pins 16 a, 16 b and secured lateral pin 20 . The bracing pins 16 a, 16 b, are slidably press fit within the block 15 and then gauge elements 14 , 18 are positioned. Bracing pins 16 a, 16 b preferably fit in channels 79 a, 79 b (shown in FIG. 11C) of gauge elements 14 , 18 . Pin 20 is also biased against the gauge elements 14 , 18 by a clamping device such as securing bolts 38 proceeding through threaded openings 39 to engage the pin 20 . Once the gauge elements 14 , 18 are placed in the block 15 and the bracing pins 16 a, 16 b are positioned in channels 79 a, 79 b of those gauge elements 14 , 18 and lateral pin 20 is in place in block 15 , the securing bolts 38 are tightened to bias the securing pin 20 against the gauge elements 14 , 18 .
FIG. 11A shows a series of four securing bolts 38 . In a preferred embodiment, each securing bolt 38 contacts a dedicated segment of the pin 20 . Pin 20 may be made of a malleable metal such as brass and either cut or scored to create segments. Thus, pin 20 may be comprised of four separate pieces. The bolts 38 are sufficiently spaced across the block 15 so that each securing bolt 38 can contact a segment of the securing pin 20 and thereby bias between about two and about four individual gauge elements 14 , 18 .
FIGS. 11B and 11C are side plan views of the modular block 15 and cut pile loopers 14 , 18 of FIG. 11A, however, FIG. 11C shows the gauge elements 14 , 18 , lateral pins 16 a, 16 b, 20 , and securing bolts 38 without the modular block 15 . It can be seen that cut pile loopers 14 , 18 are designed to engage with rear and front rows of needles respectively, although a single length of looper could be used if only one row of needles was to be used to create cut pile tufts. As best seen in FIG. 11B, the side wall of conical point 89 exerts camming pressure against lateral pin 20 . Lateral pin 20 in turn engages with the proximal ends of gauge elements 14 , 18 . FIG. 11C shows that lateral pins 16 a, 16 b and 20 are advantageously set in channels 79 a, 79 b, 79 formed in the proximal ends of the gauge elements 14 , 18 .
Although a preferred embodiment of the present invention has been disclosed in detail herein, it will be understood that various substitutions and modifications may be made to the disclosed embodiment described herein without departing from the scope and spirit of the present invention as recited in the appended claims. | Lateral pins are used to provide a tufting machine modular gauge assembly that allows damaged or broken gauge elements to be replaced individually. The modular gauge assembly consists of a gauge bar with a plurality of modular blocks removably attached to the bar. The modular blocks are six sided with a detent and fastener mechanism for attaching the block to the gauge bar. The gauge elements may be attached to the block by dedicated screw-pins or by a lateral pin that passes through all the gauge elements within a block. The lateral pin may either pierce the gauge elements or abut the gauge elements. Abutting pins may be malleable and segmented and secured in position by conical ended bolts. | 3 |
FIELD
[0001] The present disclosure relates to an information processing device, an information processing method, and a program, and specifically to an information processing device, an information processing method, and a program that can efficiently copy plural streams interleaved with respect to each data in a predetermined unit and recorded.
BACKGROUND
[0002] Recently, contents of stereoscopically viewable three-dimensional (3D) images have attracted attention. As 3D image display systems, there are various systems such as a frame-sequential system of alternately displaying images for left eye and images for right eye. In the case where any system is employed, the data volume of 3D image contents is larger than the data volume of 2D image contents.
[0003] To record high-definition contents of movies etc. as 3D images having large volume, large-capacity recording media are necessary. As the large-capacity recording media, for example, there is a Blu-ray (registered trademark) Disc (hereinafter, referred to BD as appropriate), and recording of 3D image contents in the BD is considered.
SUMMARY
[0004] However, in BD standards, how to perform Managed Copy of 3D image contents recorded in BD using a local storage of HDD (Hard Disk Drive) or the like as a copy destination is not specified. Managed Copy is one of functions of AACS as a copyright protection technology employed in BD, and a technology of copying contents recorded in BD while authenticating equipment by communication with a server or the like.
[0005] A video stream of 3D image contents includes a video stream for left eye and a video stream for right eye. Depending on management in a file system of the streams, copying may not efficiently be performed by simply designating the file and performing Managed Copy.
[0006] Thus, it is desirable to achieve efficient copy of plural streams interleaved and recorded with respect to each data in a predetermined unit in other recording media.
[0007] An information processing device according to an embodiment of the present disclosure includes a processor determining whether or not a basic stream that can be reproduced singly and an extended stream used for reproduction with the basic stream forming a video stream of contents to be copied are interleaved with respect to each data in a predetermined unit and recorded in a first recording medium based on control information as information for controlling reproduction of the contents recorded in the first recording medium, and a recording controller, in the case of a determination that the basic stream and the extended stream are interleaved with respect to each data in the predetermined unit and recorded, designating a first file of the first file that manages the basic stream, a second file that manages the extended stream, and a third file that manages the basic stream and the extended stream and allowing copying of the basic stream from the first recording medium to a second recording medium, and designating the second file and allowing copying of the extended stream from the first recording medium to the second recording medium.
[0008] The processor may change a value of recording status information representing whether or not the basic stream and the extended stream are interleaved with respect to each data in the predetermined unit and recorded contained in the control information to a value representing that the streams are not interleaved but recorded, and the recording controller may allow recording of the control information containing the recording status information in which the value has been changed in the second recording medium.
[0009] The first recording medium may be a Blu-ray Disc, and the control information may be a playlist on Blu-ray standards.
[0010] The recording status information may be contained in information on a main path referring to the basic stream forming the playlist.
[0011] The recording status information may be a sub path type as information representing a type of a sub path referring to the extended stream contained as information of an extended field in the playlist.
[0012] The processor may change the control information so that the information on the sub path contained as the information of the extended field in the playlist may be contained as information of a field for sub path different from the extended field, and the recording controller may allow recording of the control information in which the field containing the information on the sub path has been changed in the second recording medium.
[0013] The processor may delete information on respective locations of collections of source packets on the first recording medium as data in the predetermined unit forming the basic stream from first clip information referred to at reproduction of the basic stream and recorded in correspondence with the basic stream in the first recording medium, and delete information on respective locations of collections of source packets on the first recording medium as data in the predetermined unit forming the extended stream from second clip information referred to at reproduction of the extended stream and recorded in correspondence with the extended stream in the first recording medium. Further, the recording controller may allow recording of the first clip information and the second clip information from which the information on the respective locations of the collections of source packets on the first recording medium have been deleted in the second recording medium.
[0014] An information processing method according to another embodiment of the present disclosure includes determining whether or not a basic stream that can be reproduced singly and an extended stream used for reproduction with the basic stream forming a video stream of contents to be copied are interleaved with respect to each data in a predetermined unit and recorded in a first recording medium based on control information as information for controlling reproduction of the contents recorded in the first recording medium, and, in the case of a determination that the basic stream and the extended stream are interleaved with respect to each data in the predetermined unit and recorded, designating a first file among the first file that manages the basic stream, a second file that manages the extended stream, and a third file that manages the basic stream and the extended stream and allowing copying of the basic stream from the first recording medium to a second recording medium, and designating the second file and allowing copying of the extended stream from the first recording medium to the second recording medium.
[0015] A program according to still another embodiment of the present disclosure allows a computer to execute processing including determining whether or not a basic stream that can be reproduced singly and an extended stream used for reproduction with the basic stream forming a video stream of contents to be copied are interleaved with respect to each data in a predetermined unit and recorded in a first recording medium based on control information as information for controlling reproduction of the contents recorded in the first recording medium, and, in the case of a determination that the basic stream and the extended stream are interleaved with respect to each data in the predetermined unit and recorded, designating a first file among the first file that manages the basic stream, a second file that manages the extended stream, and a third file that manages the basic stream and the extended stream and allowing copying of the basic stream from the first recording medium to a second recording medium, and designating the second file and allowing copying of the extended stream from the first recording medium to the second recording medium.
[0016] In the embodiments of the present disclosure, whether or not the basic stream that can be reproduced singly and the extended stream used for reproduction with the basic stream forming the video stream of contents to be copied are interleaved with respect to each data in the predetermined unit and recorded in the first recording medium is determined based on control information as information for controlling reproduction of the contents recorded in the first recording medium. Further, in the case of the determination that the basic stream and the extended stream are interleaved with respect to each data in the predetermined unit and recorded, the first file among the first file that manages the basic stream, the second file that manages the extended stream, and the third file that manages the basic stream and the extended stream is designated and the basic stream is copied from the first recording medium to the second recording medium, and the second file is designated and the extended stream is copied from the first recording medium to the second recording medium.
[0017] According to the embodiments of the present disclosure, plural streams interleaved with respect to each data in a predetermined unit and recorded may efficiently be copied in another recording medium.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 shows a configuration example of a reproduction system including a reproducing device to which the present disclosure is applied.
[0019] FIG. 2 shows an example of imaging.
[0020] FIG. 3 is a block diagram showing a configuration example of an MVC encoder.
[0021] FIG. 4 shows an example of reference to images.
[0022] FIG. 5 shows a configuration example of TS.
[0023] FIG. 6 shows another configuration example of TS.
[0024] FIG. 7 shows an example of an arrangement of data on an optical disc.
[0025] FIG. 8 shows an example of a management structure of AV streams.
[0026] FIG. 9 shows structures of Main Path and Sub Paths.
[0027] FIG. 10 shows an example of a management structure of files recorded in an optical disc.
[0028] FIG. 11 shows syntaxes of a PlayList file.
[0029] FIG. 12 shows meanings of MVC_flag.
[0030] FIG. 13 shows meanings of MVC_file_type.
[0031] FIG. 14 shows meanings of SubPath_types.
[0032] FIG. 15 shows syntaxes of SubPath_entries_extension( )
[0033] FIG. 16 shows syntaxes of SubPath_extension( ).
[0034] FIG. 17 shows meanings of SubPath_type_extension( )
[0035] FIG. 18 shows syntaxes of STN_table_extension( ).
[0036] FIG. 19 shows syntaxes of stream_entry( )
[0037] FIG. 20 shows relationships between PlayItems and SubPlayItems.
[0038] FIG. 21 is a block diagram showing a configuration example of the reproducing device.
[0039] FIG. 22 shows a configuration example of a decode unit.
[0040] FIG. 23 shows a specific example of a PlayList file.
[0041] FIGS. 24A and 24B show syntaxes of clpi files.
[0042] FIG. 25 shows a concept of file management.
[0043] FIG. 26 is a flowchart for explanation of reproduction processing performed according to the PlayList file in FIG. 23 .
[0044] FIG. 27 shows a syntax of chunk_map( )
[0045] FIGS. 28A and 28B show specific examples of chunk_map( ).
[0046] FIG. 29 shows an example of separation of data.
[0047] FIG. 30 shows a syntax of EP_map( ).
[0048] FIGS. 31A and 31B show another example of the PlayList file.
[0049] FIG. 32 shows a concept of file management.
[0050] FIG. 33 is a flowchart for explanation of reproduction processing performed according to the PlayList file in FIG. 31A .
[0051] FIG. 34 shows yet another example of the PlayList file.
[0052] FIGS. 35A and 35B show syntaxes of clpi files.
[0053] FIG. 36 shows a concept of file management.
[0054] FIG. 37 is a flowchart for explanation of reproduction processing performed according to the PlayList file in FIG. 34 .
[0055] FIG. 38 shows a concept of file management of 3D contents to be copied.
[0056] FIG. 39 is a diagram for explanation of a problem.
[0057] FIG. 40 is a block diagram showing a functional configuration example of a controller.
[0058] FIG. 41 is a flowchart for explanation of processing of the reproducing device of copying the 3D contents in FIG. 38 .
[0059] FIG. 42 shows the PlayList file in which the value of MVC_file_type has been changed.
[0060] FIG. 43 shows Clip Information files from which chunk_map( ) has been deleted.
[0061] FIG. 44 shows a status of a local storage after copying.
[0062] FIG. 45 is a flowchart for explanation of processing of the reproducing device of reproducing the 3D contents copied by the processing in FIG. 44 .
[0063] FIG. 46 is another diagram showing the concept of file management of 3D contents to be copied.
[0064] FIG. 47 shows meanings of values of SubPath_type_extension( ).
[0065] FIG. 48 shows meanings of values of SubPath_type.
[0066] FIG. 49 is a flowchart for explanation of processing of the reproducing device of copying the 3D contents in FIG. 46 .
[0067] FIG. 50 shows the PlayList file in which the value of SubPath_type_extension( ) has been changed.
[0068] FIG. 51 shows Clip Information files from which chunk_map( ) has been deleted.
[0069] FIG. 52 is a flowchart for explanation of processing of the reproducing device of reproducing the 3D contents copied by the processing in FIG. 49 .
[0070] FIG. 53 is a flowchart for explanation of another processing of the reproducing device of copying the 3D contents in FIG. 46 .
[0071] FIG. 54 shows the PlayList file in which the location of the description of SubPath_extension( ) has been changed.
[0072] FIG. 55 is a flowchart for explanation of processing of the reproducing device of reproducing the 3D contents copied by the processing in FIG. 53 .
[0073] FIG. 56 is a block diagram showing a configuration example of hardware of a computer.
DETAILED DESCRIPTION
Configuration Example of Reproduction System
[0074] FIG. 1 shows a configuration example of a reproduction system including a reproducing device 1 to which the present disclosure is applied.
[0075] The reproduction system includes the reproducing device and a display device 3 connected using an HDMI (High Definition Multimedia Interface) cable or the like. In the reproducing device 1 , an optical disc 2 as an optical disc on BD standards such as a BD-ROM is mounted.
[0076] In the optical disc 2 , streams necessary for display of 3D images for two view points are recorded. As an encoding method for recording the streams in the optical disc 2 , for example, H.264 AVC (Advanced Video Coding)/MVC (Multi-view Video coding) is employed.
[0077] The reproducing device 1 is a player supporting 3D reproduction of the streams recorded in the optical disc 2 . The reproducing device 1 reproduces the streams recorded in the optical disc 2 and allows the display device 3 including a television receiver or the like to display 3D images obtained by reproduction. Sound is similarly reproduced by the reproducing device 1 and output from a speaker or the like provided in the display device 3 . Note that the reproducing device 1 also supports 2D reproduction like a BD player in related art.
[H.264 AVC/MVC Profile]
[0078] In H.264 AVC/MVC, an image stream called Base view video and an image stream called Dependent view video are defined. As below, H.264 AVC/MVC will appropriately and simply be referred to as MVC.
[0079] FIG. 2 shows an example of imaging.
[0080] As shown in FIG. 2 , imaging of one object is performed using an L image (left viewpoint) camera and an R image (right viewpoint) camera. Elementary streams of images imaged by the L image camera and the R image camera are input to an MVC encoder.
[0081] FIG. 3 is a block diagram showing a configuration example of the MVC encoder.
[0082] As shown in FIG. 3 , the MVC encoder includes an H.264/AVC encoder 11 , an H.264/MVC decoder 12 , a Dependent view video encoder 13 , and a multiplexer 14 .
[0083] The L image stream imaged by the L image camera is input to the H.264/AVC encoder 11 . Further, the R image stream imaged by the R image camera is input to the Dependent view video encoder 13 .
[0084] The H.264/AVC encoder 11 encodes the L image stream as H.264 AVC/High Profile video stream, for example. The H.264/AVC encoder 11 outputs the AVC video stream obtained by encoding to the H.264/MVC decoder 12 and the multiplexer 14 as a Base video stream.
[0085] The H.264/MVC decoder 12 decodes the AVC video stream supplied from the H.264/AVC encoder 11 and outputs the L image stream obtained by decoding to the Dependent view video encoder 13 .
[0086] The Dependent view video encoder 13 encodes the L image stream supplied from the H.264/MVC decoder 12 and the externally input R image stream and outputs the Dependent view video stream.
[0087] Predictive encoding using other streams as reference images is not allowed for the Base view video, however, as shown in FIG. 4 , predictive encoding using the Base view video as reference images is allowed for the Dependent view video. For example, in the case where encoding is performed with the L images as Base view video and R images as Dependent view video, the data volume of the resulting Dependent view video stream becomes smaller compared to the data volume of the Base view video stream.
[0088] Note that, because of encoding in H.264/MVC, prediction in the time direction is performed with respect to the Base view video. Further, prediction in the time direction is also performed with respect to the Dependent view video with prediction between views. To decode the Dependent view video, it is necessary to have finished the decoding of the corresponding Base view video that had been referred to at encoding.
[0089] The Dependent view video encoder 13 outputs the Dependent view video stream obtained by encoding using prediction between views as well to the multiplexer 14 .
[0090] The multiplexer 14 multiplexes the Base view video stream supplied from the H.264/AVC encoder 11 and the Dependent view video stream supplied from the Dependent view video encoder 13 as MPEG2 TS, for example. The Base view video stream and the Dependent view video stream may be multiplexed into one MPEG2 TS or contained in separate MPEG2 TS.
[0091] The multiplexer 14 outputs the generated TS (MPEG2 TS). The TS output from the multiplexer 14 is recorded in the optical disc 2 with other management data in the recording device, and supplied to the reproducing device 1 .
[0092] In this example, encoding is performed using the MVC method with the L images as Base view video and R images as Dependent view video, however, oppositely, encoding may be performed with the R images as Base view video and L images as Dependent view video. As below, encoding with the R images as Base view video and L images as Dependent view video will be explained.
[0093] When performing 3D reproduction in response to a command by a user or the like, the reproducing device 1 reads out the Base view video stream and the Dependent view video stream from the optical disc 2 and reproduces them.
[0094] Further, when performing 2D reproduction, the reproducing device 1 reads out only the Base view video stream from the optical disc 2 and reproduces it. Since the Base view video stream is the AVC video stream encoded in H.264/AVC, any player compliant with the BD format may reproduce the Base view video stream and display 2D images.
Configuration Example of TS
[0095] FIG. 5 shows a configuration example of the TS recorded in the optical disc 2 .
[0096] In Main TS in FIG. 5 , the respective streams of Base view video, Dependent view video, Primary audio, Base PG, Dependent PG, Base IG, Dependent IG are multiplexed. Likewise, the Dependent view video stream may be contained in the Main TS as one TS with the Base view video stream.
[0097] The Main TS is TS containing at least Base view video stream. On the other hand, Sub TS is TS containing streams other than the Base view video stream and is used with the Main TS at reproduction. In the optical disc 2 , the Sub TS is appropriately recorded in addition to the Main TS.
[0098] For making 3D display possible like videos, the respective streams of Base view and Dependent view are prepared with respect to PG (Presentation Graphics) such as caption and IG (Interactive Graphics) such as a menu screen.
[0099] FIG. 6 shows another configuration example of TS recorded in the optical disc 2 .
[0100] In Main TS in FIG. 6 , the respective streams of Base view video, Primary audio, Base PG, Dependent PG, Base IG, Dependent IG are multiplexed.
[0101] On the other hand, a Dependent view video stream is contained in the Sub TS. Likewise, the Dependent view video stream may be contained in another TS than that of the Base view video stream.
[0102] As shown in FIG. 6 , when the Dependent view video stream and the Base view video stream are contained in separate TS, the respective TS files are interleaved and recorded in the optical disc 2 .
[0103] FIG. 7 shows an example of an arrangement of TS files containing Base view video streams (L video streams) and TS files containing Dependent view video streams (R video streams) in the optical disc 2 .
[0104] As shown in FIG. 7 , the TS files containing the L video streams and the TS files containing the R video streams are interleaved to be alternately arranged with respect to each predetermined data unit, and recorded in the optical disc 2 . A collection of source packets belonging to one TS file and continuously arranged on the optical disc 2 is referred to as “chunk”.
[0105] In FIG. 7 , the respective blocks shown with characters “R” and numbers represent chunks of R video and the respective blocks shown with characters “L” and numbers represent chunks of L video.
[0106] At 3D reproduction, they are read out from the optical disc 2 in the order of R[0], L[0], R[1], L[1], R[2], L[2], R[3], L[3], R[4], L[4], R[5], L[5], . . . , and decoded in the order of L[0], R[0], L[1], R[1], L[2], R[2], L[3], R[3], L[4], R[4], L[5], R[5], . . . . As described above, to decode the R video, it is necessary that the L video that had been referred to at encoding has been decoded. The chunk of R video and the chunk of L video with the same number are data necessary for reproduction at the same time and used as a set at 3D reproduction.
[0107] That is, for simplicity of explanation, the case where the entire reproduction time of the contents is equally divided into three is considered. Given that the start time of reproduction is zero, the times at which the entire reproduction time of the contents is equally divided into three are time-sequentially expressed by t 1 , t 2 , and the L video data necessary for the reproduction time from the start time of reproduction to the time t 1 is divided as chunk L[0].
[0108] Further, the L video data necessary for the reproduction time from the time t 1 to the time t 2 is divided as chunk L[1], and the L video data necessary for the reproduction time from the time t 2 to the end time is divided as chunk L[2].
[0109] In the same manner, regarding the R video streams, the R video data necessary for the reproduction time from the start time of reproduction to the time t 1 is divided as chunk R[0].
[0110] Further, the R video data necessary for the reproduction time from the time t 1 to the time t 2 is divided as chunk R[1], and the R video data necessary for the reproduction time from the time t 2 to the end time is divided as chunk R[2].
[0111] Thus divided and obtained respective chunks are arranged so that the chunks with the same numbers may be located in the order of the R video chunk and the L video chunk, and recorded in the optical disc 2 . Note that, as shown in FIG. 5 , both the L video stream and the R video stream are contained in one TS, the TS file is not interleaved but recorded in the optical disc 2 .
[Management Structure of AV Streams]
[0112] FIG. 8 shows an example of a management structure of AV streams according to the reproducing device 1 .
[0113] The management of AV streams is performed using two layers of PlayList and Clip as shown in FIG. 8 . The AV streams may be recorded in the local storage of the reproducing device 1 not in the optical disc 2 . Clip includes the AV stream as TS obtained by multiplexing of video data and audio data and corresponding Clip Information (Clip Information containing attribute information on the AV stream).
[0114] The AV stream is developed on the time axis, and the respective access points are designated by time stamp in the PlayLists. The Clip Information is used for finding an address at which decoding is to be started in the AV stream.
[0115] The PlayList is a collection of reproduction sections of the AV stream. One reproduction section in the AV stream is referred to as PlayItem. The PlayItem is expressed by a pair of IN point and OUT point of the reproduction section on the time axis. The PlayList includes one or some PlayItems.
[0116] The first PlayList from the left in FIG. 8 includes two PlayItems and the first half part and the second half part of the AV stream contained in the left Clip are respectively referred to by the two PlayItems.
[0117] The second PlayList from the left includes one PlayItem and the entire AV stream contained in the right Clip is referred to by it.
[0118] The third PlayList from the left includes two PlayItems and a part of the AV stream contained in the left Clip and a part of the AV stream contained in the right Clip are respectively referred to by the two PlayItems.
[0119] For example, in the case where the left PlayItem contained in the first PlayList from the left is designated as a target of reproduction by a navigation program, the first half part of the AV stream contained in the left Clip referred to by the PlayItem is reproduced. In this manner, the PlayList is used as reproduction control information for controlling the reproduction of the AV stream.
[0120] In the PlayList, a reproduction path including a sequence of one or more PlayItems is referred to as Main Path.
[0121] Further, in the PlayList, a reproduction path including a sequence of one or more SubPlayItems is referred to as Sub Path.
[0122] FIG. 9 shows structures of Main Path and Sub Paths.
[0123] The PlayList may have one Main Path and one or more Sub Paths. The above described L video stream is referred to by the PlayItem forming the Main Path. Further, the R video stream is referred to by the SubPlayItem forming the Sub Path (Sub Path within the Extension( ) which will be described later).
[0124] The PlayList in FIG. 9 has one Main Path including a sequence of three PlayItems and three Sub Paths. For the PlayItems forming the Main Path, IDs are respectively and sequentially set from the first one. IDs are also respectively set for the Sub Paths.
[0125] In the example in FIG. 9 , one SubPlayItem is contained in the Sub Path of Subpath_id=0, and two SubPlayItems are contained in the Sub Path of Subpath_id=1. Further, one SubPlayItem is contained in the Sub Path of Subpath_id=2.
[0126] The AV stream referred to by a certain PlayItem and the AV stream referred to by the SubPlayItem that designates the reproduction section in a time zone overlapping with that of the PlayItem are reproduced in synchronization. The management of AV streams using PlayList, PlayItem, SubPlayItem is disclosed in JP-A-2008-252740 and JP-A-2005-348314, for example.
[Directory Structure]
[0127] FIG. 10 shows an example of a management structure of files recorded in the optical disc 2 .
[0128] As shown in FIG. 10 , the files are hierarchically managed using a directory structure. On the optical disc 2 , one root directory is created. Under the root directory, there is a range managed by one recording and reproduction system.
[0129] Under the root directory, a BDMV directory is placed. Immediately under the BDMV directory, an Index file as a file for which a name “Index.bdmv” is set and a Movie Object file as a file for which a name “MovieObject.bdmv” is set are stored.
[0130] Under the BDMV directory, a PLAYLIST directory, a CLIPINF directory, a STREAM directory, etc. are provided.
[0131] In the PLAYLIST directory, PlayList files as files describing PlayLists are stored. For the respective PlayList files, names including five-digit numbers in combination with extensions “.mpls” are set. For the Playlist file shown in FIG. 10 , a file name “00001.mpls” is set.
[0132] In the CLIPINF directory, Clip Information files as files describing Clip Information are stored. For the respective Clip Information files, names including five-digit numbers in combination with extensions “.clpi” are set.
[0133] For the two Clip Information files in FIG. 10 , file names “00001.clpi” and “00002.clpi” are respectively set. Hereinafter, appropriately, the Clip Information file will be referred to as “clpi file”.
[0134] The clpi file of “00001.clpi” is a file in which information on the corresponding L video stream is described, and the clpi file of “00002.clpi” is a file in which information on the corresponding R video stream is described.
[0135] In the STREAM directory, stream files are stored. For the respective stream files, names including five-digit numbers in combination with extensions “.m2ts” or names including five-digit numbers in combination with extensions “.ilvt” are set. Hereinafter, appropriately, the file for which the extension “.m2ts” is set will be referred to as “m2ts file” and the file for which the extension “.ilvt” is set will be referred to as “ilvt file”.
[0136] The m2ts file of “00001.m2ts” is a file of the L video stream and the m2ts file of “00002.m2ts” is a file of the R video stream.
[0137] The ilvt file of “00001.ilvt” is a file, when the m2ts file of the L video stream file and the m2ts file of the R video stream file are interleaved, for managing the stream files and performing 3D reproduction. Therefore, in the case where the L video stream file and the R video stream are contained in one TS, but their m2ts files are not interleaved, the ilvt file is not recorded in the optical disc 2 .
[0138] In addition to those shown in FIG. 10 , under the BDMN directory, a directory that stores files of audio streams etc. are provided.
[0139] In the example of FIG. 10 , the file name of the m2ts file forming the Clip on the L video is “00001.m2ts” and the file name of the clpi file is “00001.clpi”. Further, the file name of the m2ts file forming the Clip on the R video is “00002.m2ts” and the file name of the clpi file is “00002.clpi”. The file name of the m2ts file and the file name of the clpi file forming one Clip contains the same number.
[0140] In the file name of the ilvt file contains the same number “00001” as the five-digit number respectively contained in the file name of the m2ts file and the file name of the clpi file forming the Clip on L video. Thereby, the file name of the ilvt file to be designated at 3D reproduction may be specified from the file name of the clpi file forming the Clip on L video.
[Syntaxes of Respective Data]
[0141] FIG. 11 shows syntaxes of a PlayList file.
[0142] For convenience of explanation, numbers indicating the numbers of lines and “:” are shown on the left side of FIG. 11 . The numbers indicating the numbers of lines and “:” do not form the PlayList. Note that, here, the main description of the PlayList will be explained, and the detailed explanation will be omitted. The details will be described in Blu-ray Disc Read Only Format part3, for example.
[0143] “yyyyy.mpls” on the 1st line shows the file name of the PlayList.
[0144] As shown in the 2nd line to the 5th lines, the PlayList file roughly includes fields of AppInfoPlayList( ), PlayList( ), PlayListMark( ), ExtensionData( ). In the PlayListMark( ) on the 4th line, information on user operation of commanding chapter jump etc. or marks as jump destinations by commands or the like is described.
[0145] The 7th line to the 11th line are the field of AppInfoPlayList( ). The AppInfoPlayList( ) contains MVC_flag as one-bit flag representing whether or not information on MVC reproduction (3D reproduction) is contained in the PlayList as shown on the 9th line. Note that the MVC_flag may be contained in a stream such as a video stream, not contained in the PlayList.
[0146] FIG. 12 shows meanings of MVC_flag.
[0147] As shown in FIG. 12 , the value “0” of the MVC_flag shows that the information on 3D reproduction is not contained in the PlayList. That is, the optical disc in which the PlayList of MVC_flag=0 is a disc that does not support 3D reproduction.
[0148] The value “1” of the MVC_flag shows that the information on 3D reproduction is contained in the PlayList.
[0149] In the AppInfoPlayList( ), information on the type of the PlayList showing that the PlayList is for random reproduction or the like is contained in addition to the MVC_flag.
[0150] The 12th line to the 25th line are the field of PlayList( ). The number_of PlayItems on the 13th line shows the number of PlayItems in the PlayList. In the case of the example of FIG. 9 , the number of PlayItems is three. The values of PlayItem_ids are assigned from zero in the order of appearance of PlayItem( ) in the PlayList. In the for loop on the 15th line to the 19th line, the PlayItem( ) is referred to by the number of PlayItems.
[0151] The number_of_SubPaths on the 14th line indicates the number of Sub Paths in the PlayList( ). In the case of the example of FIG. 9 , the number of Sub Paths is three. The values of SubPath_ids are assigned from zero in the order of appearance of SubPath( ) in the PlayList. In the for loop on the 20th line to the 24th line, the SubPath( ) is referred to by the number of Sub Paths.
[0152] The 26th line to the 33rd line are a description of the PlayItem( ) The Clip_Information_file_name on the 27th line shows the name of the clpi file of the Clip containing the AV stream referred to by the PlayItem.
[0153] The MVC_file_type on the 28th line is 2-bit data having a valid value when the value of the MVC_flag is “1”, and shows the types of the files as the respective supply sources of the L video stream and the R video stream.
[0154] FIG. 13 shows meanings of MVC_file_type.
[0155] As shown in FIG. 13 , the value “0” of the MVC_file_type shows that the L video stream and the R video stream are contained in one TS and the m2ts file that manages the TS is indicated by the Clip_Information_file_name.
[0156] As described above, the file name of the m2ts and the file name of the clpi file forming a certain Clip contain the same number. The Clip_Information_file_name also indicates the file name of the corresponding m2ts file forming the same Clip as the clpi file for which the file name is set.
[0157] The value “1” of the MVC_file_type shows that the m2ts file (first TS file) of the L video stream and the m2ts file (second TS file) of the R video stream indicated by the Clip_Information_file_name are interleaved on the optical disc 2 . In this case, the L video stream and the R video stream are respectively contained in different TS.
[0158] The value “2” of the MVC_file_type shows that both or one of the m2ts file of the L video stream and the m2ts file of the R video stream indicated by the Clip_Information_file_name is recorded in the local storage within the reproducing device 1 .
[0159] The value “3” of the MVC_file_type is a reserved value.
[0160] Returning to the explanation of FIG. 11 , the IN_time on the 30th line shows the start location of the reproduction section of the PlayItem, and the OUT_time on the 31st line shows the end location.
[0161] In the STN_table( ) on the 32nd line, information of the AV stream referred to by the PlayItem is contained. For example, as the information of the AV stream referred to by the PlayItem, a stream number (ID) and a PID of a transport packet forming the L video stream are contained.
[0162] The 34th line to the 40th line are description of the SubPath( ) contained in the PlayList( ). The SubPath( ) on the 34th line to the 40th line includes information on video data other than the R video and information on audio data reproduced together with the AV stream referred to by the PlayItem.
[0163] The SubPath_type on the 35th line is 8-bit data representing the type of the Sub Path.
[0164] FIG. 14 shows meanings of SubPath_type.
[0165] As shown in FIG. 14 , the type of the Sub Path is indicated by the value from “2” to “7”. For example, SubPath_type=2 indicates the SubPath of audio data used at slide show (Browsable slideshow) reproduction, and SubPath_type=3 indicates the SubPath of data at display of an interactive menu.
[0166] The number_of_SubPlayItems on the 36th line in FIG. 11 is 8-bit data indicating the number of SubPlayItems (number of entries) in one Sub Path( ). For example, the number_of_SubPlayItems of the SubPlayItem with SubPath_id=0 is “1”, and the number_of_SubPlayItems of the SubPlayItem with SubPath_id=1 is “2”. In the for loop on the 37th line to the 39th line, the SubPlayItem( ) is referred to by the number of SubPlayItems.
[0167] The 41st line to the 45th line are description of the SubPlayItem( ) contained in the SubPath( ). The Clip_Information_file_name on the 42nd line shows the name of the clpi file of the Clip referred to by the SubPlayItem.
[0168] The SubPlayItem_IN_time on the 43rd line shows the start location of the reproduction section of the SubPlayItem, and the SubPlayItem_OUT_time on the 44th line shows the end location.
[0169] The 46th line to the 49th line are ExtensionData( ) as an extension field.
[0170] When the value of the MVC_flag is “1”, SubPath_entries_extension( ) and STN_table extension( ) are described in the ExtensionData( ). The SubPath_entries_extension( ) and STN_table extension( ) contain information on the R video stream used for 3D reproduction together with the L video stream referred to by the PlayItem.
[0171] The R video stream is managed as a stream referred to by the SubPath, and, as described above, the information on the R video stream is not described in the field of the SubPath( ) (the 34th line in FIG. 11 ), but described in the field of the ExtensionData( ).
[0172] In the case where the information on the R video stream has been described in the field of the SubPath( ) a failure may be caused if a player that does not support 3D reproduction loads the description. The information on the R video stream is described as ExtensionData( ) in advance and a player that supports 3D reproduction loads the description only when performing 3D reproduction, and thereby, the failure may be prevented.
[0173] FIG. 15 shows syntaxes of SubPath_entries_extension( ).
[0174] The number_of_SubPath_extensions is 16-bit data representing the number of SubPath_extensions, i.e., the number of SubPath_extension( ) appearing in the SubPath_entries_extension( ). In the for loop subsequent to the number_of_SubPath_extensions, the SubPath_extension( ) is referred to by the number of SubPaths.
[0175] Here, to the SubPath referring to the R video stream, an ID is also assigned as is the case of the normal Subpath referring to video data and audio data other than the R video on which information is described in the SubPath( ) on the 34th line in FIG. 11 .
[0176] As shown in a for loop in FIG. 15 , the ID of the SubPath referring to the R video stream is started from the same value as the value of the number_of_SubPaths on the 14th line in FIG. 11 , and incremented one by one at each time when the SubPath_extension( ) is referred to. For example, in the case where the normal number of SubPaths is “3” and number_of_SubPaths=3 as shown in FIG. 9 , if the number_of_SubPath_extensions is “2”, “3” is assigned to the ID of the first SubPath and “4” is assigned to the ID of the second SubPath.
[0177] FIG. 16 shows syntaxes of the SubPath_extension( ) in FIG. 15 .
[0178] Length is 32-bit data representing the number of bytes from immediately after the length field to the end of the SubPath_extension( ).
[0179] The SubPath_type_extension is formed by extending the SubPath_type, and 8-bit data representing the type of SubPath in which information is described in the SubPath_extension( ).
[0180] FIG. 17 shows meanings of SubPath_type_extension.
[0181] As shown in FIG. 17 , values “0” to “7” of the SubPath_type_extension respectively represent the same meanings of the values “0” to “7” of the SubPath_type in FIG. 14 .
[0182] The value “8” of the SubPath_type_extension shows that the SubPath for which SubPath_type_extension=8 is set is the SubPath referring to the R video stream. Further, the value shows that the m2ts file of the R video stream referred to is another file than the m2ts file of the L video stream referred to by the Play Item.
[0183] Returning to the explanation of FIG. 16 , the number_of_SubPlayItems is 8-bit data representing the number of SubPlayItems in the SubPath_extension( ) In a for loop subsequent to the number_of_SubPlayItems, the SubPlayItem( ) is referred to by the number_of_SubPlayItems.
[0184] The description of the SubPlayItem( ) in the SubPath_extension is the same description of the SubPlayItem( ) shown on the 41st line to the 45th line in FIG. 11 .
[0185] That is, the SubPlayItem( ) in the SubPath_extension contains Clip_Information_file_name showing the file name of the clpi file contained in the same Clip as that of the R video stream referred to by the SubPlayItem. Further, it contains the SubPlayItem_IN_time indicating the start location of the reproduction section and the SubPlayItem_OUT_time indicating the end location.
[0186] FIG. 18 shows syntaxes of STN_table_extension( ) contained in ExtensionData( ).
[0187] As described above, the STN_table (on the 32nd line in FIG. 11 ) contains a PID of a transport packet forming the L video stream referred to by the PlayItem. On the other hand, the STN_table_extension( ) contains a PID of a transport packet forming the R video stream referred to by the SubPath (SubPath_extension).
[0188] As shown in FIG. 18 , the STN_table_extension( ) contains the length representing the length of the STN_table_extension( ) and subsequently, stream_entry( ) and stream_attributes( ) as attribute information of the R video stream as information on the R video stream.
[0189] FIG. 19 shows an example of syntaxes of stream_entry( )
[0190] As shown in FIG. 19 , the stream_entry( ) contains length representing the length of the stream_entry( ) and subsequently, type as 8-bit information.
[0191] For example, the value “1” of the type shows that the R video stream is contained in one TS together with the L video stream referred to by the PlayItem. Further, the value “2” of the type at least shows that the R video stream is contained in another TS than that of the L video stream referred to by the PlayItem.
[0192] When the value of the type is “1”, ref_to_stream_PID_of_mainClip is referred to. The ref_to_stream_PID_of_mainClip represents the PID of the transport packet forming the R video stream contained in one TS together with the L video stream.
[0193] When the value of the type is “2”, ref_to_SubPath_id, ref_to_subClip_entry_id, ref_to_stream_PID_of_subClip are referred to. Of the three pieces of information, the ref_to_SubPath_id represents the ID of the SubPath (SubPath_extension) referring to the R video stream. Further, the ref_to_stream_PID_of_subClip represents the PID of the transport packet forming the R video stream referred to by the SubPath identified by the ref_to_SubPath_id.
[0194] FIG. 20 shows relationships between the SubPath for which the SubPath_type_extension=8 is set and the MainPath referring to the L video stream to which the SubPath is related in the Playlist.
[0195] As described above, in each PlayItem( ) the IN_time indicating the start location of the reproduction section and the OUT_time indicating the end location of the PlayItem are contained (on the 30th line, 31st line in FIG. 11 ).
[0196] Further, as described above, in the SubPlayItem( ) in the SubPath_extension( ) with respect to each SubPlayItem forming the SubPath referring to the R video stream, the SubPlayItem_IN_time indicating the start location of the reproduction section and the SubPlayItem_OUT_time indicating the end location are contained.
[0197] As shown in FIG. 20 , the start location and the end location of the PlayItem and the start location and the end location of the SubPlayItem referring to the R video stream related to the L video stream referred to by the PlayItem are the same, respectively.
[0198] For example, the IN_time and the OUT_time of the PlayItem to which PlayItem id=0 is assigned coincide with SubPlayItem_IN_time and SubPlayItem_OUT_time of SubPlayItem# 0 related to the PlayItem to which PlayItem id=0 is assigned.
[0199] As described above, in the PlayList, SubPath( ) as the field in which information on SubPath is described is defined as SubPath_extension( ) in the ExtensionData( ) as the extension field, and further, the STN_table( ) as the field in which information on the stream number (STream Number) is described is defined as STN_table_extension( ).
Configuration Example of Reproducing Device 1
[0200] FIG. 21 is a block diagram showing a configuration example of the reproducing device 1 .
[0201] A controller 31 executes a control program prepared in advance and controls the entire operation of the reproducing device 1 .
[0202] A disk drive 32 reads out data from the optical disc 2 according to the control by the controller 31 , and outputs the read out data to the controller 31 , a memory 33 , or a decode unit 36 .
[0203] The memory 33 appropriately stores data necessary for execution of various kinds of processing by the controller 31 .
[0204] A local storage 34 includes an HDD (Hard Disk Drive) or an SSD (Solid State Drive), for example. In the local storage 34 , R video streams downloaded from a server 22 etc. are recorded. Also the streams recorded in the local storage 34 are appropriately supplied to the decode unit 36 .
[0205] An Internet interface 35 communicates with the server 22 via a network 21 according to the control by the controller 31 and supplies data downloaded from the server 22 to the local storage 34 .
[0206] From the server 22 , data for updating the data recorded in the optical disc 2 is downloaded. As will be described later, 3D reproduction of contents may be performed using the downloaded R video stream in combination with the L video stream recorded in the optical disc 2 .
[0207] The decode unit 36 decodes the stream supplied from the disk drive 32 or the local storage 34 and outputs obtained video signals to the display device 3 . Audio signals are also output to the display device 3 via a predetermined route.
[0208] An operation input unit 37 includes an input device such as a button, a key, a touch panel, and a mouse and a receiving part that receives signals of infrared light or the like transmitted from a predetermined remote commander. The operation input unit 37 detects an operation of a user and supplies signals representing the detected operation to the controller 31 .
[0209] FIG. 22 shows a configuration example of the decode unit 36 .
[0210] A separation part 51 separates the data supplied from the disk drive 32 into Main TS data and Sub TS data according to the control by the controller 31 .
[0211] The separation part 51 outputs the separated Main TS data to a read buffer 52 for storage and outputs the Sub TS data to a read buffer 55 for storage. Further, the separation part 51 outputs the Sub TS data supplied from the local storage 34 to the read buffer 55 for storage.
[0212] A PID filter 53 sorts the transport packet of the Main TS formed by the data stored in the read buffer 52 based on the PID. From the controller 31 , the PID of the transport packet forming the L video stream specified based on the STN_table( ) of the PlayList (on the 32nd in FIG. 11 ) and the PID of the transport packet forming the R video stream specified based on the ref_to_stream_PID_of subClip of the STN_table_extension( ) ( FIG. 19 ) are designated.
[0213] The PID filter 53 reads out the transport packet of the L video stream from the read buffer 52 and outputs it to an ES buffer 54 for storage. In the ES buffer 54 , ES (Elementary Stream) of the L video is stored.
[0214] Further, when the R video stream is multiplexed together with the L video stream in the Main TS, the PID filter 53 extracts the transport packet of the R video stream based on the PID and outputs it to a switch 57 .
[0215] A PID filter 56 reads out the transport packet of the R video stream contained in the Sub TS from the read buffer 55 and outputs it to the switch 57 . From the controller 31 , the PID of the transport packet forming the R video stream specified based on the ref_to_stream_PID_of subClip of the STN_table_extension( ) ( FIG. 19 ) is designated.
[0216] Here, the processing of the L video, R video streams is being explained, however, as has been explained with reference to FIG. 5 , graphics data such as PG and IG may be multiplexed in the Main TS. Similarly, graphics data such as PG and IG may be multiplexed in the Sub TS.
[0217] The PID filter 53 and the PID filter 56 appropriately sort the data as well based on the PIDs, and output them to predetermined output destinations. To terminals (circles) of the output destinations shown in the blocks of the PID filter 53 and the PID filter 56 in FIG. 22 , decoders that decode graphics data etc. are connected.
[0218] The switch 57 outputs the transport packet of the R video stream contained in the Main TS supplied from the PID filter 53 to an ES buffer 58 for storage. Further, the switch 57 outputs the transport packet of the R video stream contained in the Sub TS supplied from the PID filter 56 to the ES buffer 58 for storage. In the ES buffer 58 , ES of the R video is stored.
[0219] A switch 59 outputs the packet to be decoded of the packet of the L video stored in the ES buffer 54 and the packet of the R video stored in the ES buffer 58 to a decoder 60 . Time information such as DTS (Decoding Time Stamp) is set for PES packets of the L video and the R video, and readout from the buffers is performed based on the time information.
[0220] The decoder 60 decodes the packet supplied form the switch 59 and outputs video signals of the L video or the R video obtained by decoding.
Specific Example 1 of PlayList File
[0221] FIG. 23 shows a specific example of a PlayList file.
[0222] FIG. 23 shows a part of the information shown in FIG. 11 , etc. This is the same for the following specific examples of PlayLists.
[0223] The PlayList file in FIG. 23 is a PlayList file that controls 3D reproduction when the L video stream and R video stream are contained in the respective separate TS and the TS files are interleaved and recorded in the optical disc 2 .
[0224] That is, MVC_flag=1 as shown in the AppInfoPlayList( ) in FIG. 23 , and MVC_file_type=1 as shown in the PlayItem( ).
[0225] The Clip_Information_file_name of the PlayItem( ) is “00001”. From the description, the clpi file forming the Clip of the L video is specified. Further, from the IN_time and the OUT_time of the PlayItem( ), the start location and the end location of the reproduction section of the PlayItem are respectively specified, and, from the STN_table( ), the PID of the transport packet forming the L video stream is specified.
[0226] In the ExtensionData( ) information on the SubPath referring to the R video stream is described. In this example, the normal number of SubPaths is “0” (the value of the number_of_SubPaths (on the 14th line in FIG. 11 ) is “0”), and SubPath_id=0 is assigned to the SubPath referring to the R video stream. In the SubPath_extension( ), SubPath_type_extension=8 indicating the SubPath referring to the R video stream is set.
[0227] The Clip_Information_file_name of the SubPlayItem( ) of the ExtensionData( ) is “00002”. From the description, the clpi file forming the Clip of the R video is specified. Further, from the SubPlayItem_IN_time and the SubPlayItem_OUT_time of the SubPlayItem( ) the start location and the end location of the reproduction section of the SubPlayItem are respectively specified.
[0228] From the STN_table_extension( ), the ID “0” of the SubPath referring to the R video stream (ref_to_SubPath_id=0) and the PID of the transport packet forming the R video stream (ref_to_R_video_PID) are specified. In this example, the value of the type of the STN_table_extension( ) is “2”.
[0229] FIGS. 24A and 24B show syntaxes of clpi files.
[0230] FIG. 24A shows an example of the clpi file of “00001.clpi”.
[0231] Number_of_source_packets 1 shows the number of source packets contained in the m2ts file of “00001.m2ts”.
[0232] EP_map contains location information of the entry point (EP) set for the TS contained in the m2ts file of “00001.m2ts”.
[0233] Chunk_map( ) contains location information of the respective chunks of the m2ts file of “00001.m2ts”. The location of each chunk is indicted by Source Packet Number (SPN), for example. A specific example of the chunk_map( ) will be described later.
[0234] FIG. 24B shows an example of the clpi file of “00002.clpi”.
[0235] Like the clpi file of “00001.clpi”, the clpi file of “00002.clpi” contains number_of_source_packets 2 showing the number of source packets contained in the m2ts file of “00002.m2ts”, EP_map, and chunk_map( ).
[0236] FIG. 25 shows a concept of file management.
[0237] As shown in FIG. 25 , management of the files interleaved and recorded in the optical disc 2 is performed in the form of a three-layer structure of a physical layer, a file system layer, and an application layer. The PlayList file in FIG. 23 and the clpi files in FIGS. 24A and 24B are information of the application layer handled by an application that manages reproduction of contents.
[0238] The physical layer is a layer of the optical disc 2 in which the m2ts file of the L video stream and the m2ts file of the R video stream are interleaved and recorded.
[0239] In the file system layer, the stream files (m2ts files, ilvt file) designated by the application are brought into correspondence with the locations of extents forming the respective stream files on the optical disc 2 . The file system is a UDF file system, for example.
[0240] The extents refer to the respective collections of data continuously provided on the optical disc 2 of the entire data managed by a particular file.
[0241] That is, in the example of FIG. 25 , in the m2ts file of “00001.m2ts”, L[0], L[1] are the extents. When the m2ts file of “00001.m2ts” is designated as a readout file by the application, the respective locations of the L[0], L[1] on the optical disc 2 are specified by the UDF file system and read out by the disk drive 32 .
[0242] In the m2ts file of “00002.m2ts”, R[0], R[1] are the extents. When the m2ts file of “00002.m2ts” is designated as a readout file by the application, the respective locations of the R[0], R[1] on the optical disc 2 are specified by the UDF file system and read out by the disk drive 32 .
[0243] In the ilvt file of “00001.ilvt”, the whole R[0], L[0], R[1], L[1] are one extent. When the ilvt file of “00001.ilvt” is designated as a readout file by the application, the locations of the R[0], L[0], R[1], L[1] on the optical disc 2 are specified by the UDF file system and read out by the disk drive 32 .
Example 1 of Reproduction Processing
[0244] Here, processing of 3D reproduction performed according to the PlayList file in FIG. 23 will be explained with reference to a flowchart in FIG. 26 .
[0245] If MVC_flag=1, the controller 31 (the application that manages reproduction of contents executed in the controller 31 ) starts 3D reproduction in response to an operation for the operation unit 37 carried by a user.
[0246] At step S 1 , the controller 31 specifies the PID of the transport packet of the Main TS forming the L video stream from the description of the STN_table( ).
[0247] At step S 2 , the controller 31 specifies ref_to_SubPath_id=0 as the value of the SubPath_id of the SubPath referring to the R video stream, and further, specifies the PID of the transport packet of the Sub TS forming the R video stream from the description of the STN_table_extension( ).
[0248] At step S 3 , the controller 31 specifies the file name of the clpi file corresponding to the m2ts file of the Main TS containing the L video stream as “00001.clpi” from the Clip_Information_file_name in the PlayItem( ).
[0249] At step S 4 , the controller 31 specifies the file name of the clpi file corresponding to the m2ts file containing the R video stream as “00002.clpi” from the Clip_Information_file_name in the SubPlayItem( ) of the SubPath having SubPath_id=0 for which SubPath_type=8 is set in the SubPath_entries_extension( ).
[0250] At step S 5 , the controller 31 specifies the ilvt file of “00001.ilvt” containing the same five characters as the number (00001) contained in the file name of the file forming the Clip of the L video with extension of ilvt. As described above, the file name of the ilvt file contains the same number as the numbers contained in the names of the m2ts file and the clpi file forming the Clip of the L video.
[0251] At step S 6 , the controller 31 uses “00001.ilvt” specified at step S 3 as a readout file and allows the disk drive 32 to readout it from the optical disc 2 through the UDF file system. The data of the L video stream and the R video stream read out from the disk drive 32 as the data of the ilvt file of “00001.ilvt” are supplied to the separation part 51 of the decode unit 36 .
[0252] Note that, when random access is designated or the like and decoding is started from a predetermined EP contained in the EP_map, the data of and after the EP of the data of the readout file are readout. The EP_map contains location information of numbers of source packets for designating the locations of the respective EPs.
[0253] At step S 7 , the controller 31 controls the separation part 51 to separate the data read out from the optical disc 2 into data of L video and R video based on the chunk_map( ) of the clpi file of “00001.clpi” and the chunk_map( ) of the clpi file of “00002.clpi”.
[0254] The data of the L video stream separated by the separation part 51 is output to the read buffer 52 and the data of the R video stream is output to the read buffer 55 . The separation of data performed using the chunk_map( ) will be described later.
[0255] The transport packet of the data of the L video stream stored in the read buffer 52 is extracted by the PID filter 53 based on the PID specified at step S 1 , and the data is supplied to the decoder 60 via the ES buffer 54 and the switch 59 . The transport packet of the data of the R video stream stored in the read buffer 55 is extracted by the PID filter 56 based on the PID specified at step S 2 , and the data is supplied to the decoder 60 via the switch 57 , the ES buffer 58 , and the switch 59 .
[0256] At step S 8 , the decoder 60 decodes (reproduces) the packets sequentially supplied from the switch 59 .
[0257] The 3D reproduction when the L video stream and R video stream are contained in the respective separate TS and the TS files are interleaved and recorded in the optical disc 2 is performed in the following manner.
[0000] [Separation of Data Using chunk_map( )]
[0258] FIG. 27 shows an example of a syntax of the chunk_map( ).
[0259] Number_of_chunks indicates the number of chunks referred to. After the number_of_chunks, information on the chunks is described by the number designated here.
[0260] SPN_chunk_start[i] shows, with the start location of the first chunk as reference, for example, the SPNs (Source Packet Number) (length) from the reference location to the start location of each chunk. The SPNs of the start locations of the respective chunks are sequentially described from that of the first chunk.
[0261] FIGS. 28A and 28B show specific examples including chunk_map( ).
[0262] FIG. 28A shows the clpi file of “00001.clpi”, and number_of_source_packets is “number_of_source_packets 1 ”. Further, the number_of_chunks of the chunk_map( ) is “n+1” and the SPN_chunk_start[i] is 0, a 1 , a 2 , . . . , an.
[0263] The first value “0” of the SPN_chunk_start[i] shows that, with the start location of the first chunk of the m2ts file of “00001.m2ts” as reference, the SPN from the reference location to the start location of L[0] as the first chunk is “0” as shown in the middle part of FIG. 29 .
[0264] The second value “a 1 ” shows that the SPN from the reference location to the start location of L[1] as the second chunk is “a 1 ”.
[0265] The third value “a 2 ” shows that the SPN from the reference location to the start location of L[2] as the third chunk is “a 2 ”.
[0266] The (n+1)th value “an” shows that the SPN from the reference location to the start location of L[n] as the last chunk is “an”.
[0267] FIG. 28B shows the clpi file of “00002.clpi”, and number_of_source_packets is “number_of_source_packets 2 ”. Further, the number_of_chunks of the chunk_map( ) is “n+1” and the SPN_chunk_start[i] is 0, b 1 , b 2 , . . . , bn.
[0268] The first value “0” of the SPN_chunk_start[i] shows that, with the start location of the first chunk of the m2ts file of “00002.m2ts” as reference, the SPN from the reference location to the start location of R [0] as the first chunk is “0” as shown in the top part of FIG. 29 .
[0269] The second value “b 1 ” shows that the SPN from the reference location to the start location of R [1] as the second chunk is “b 1 ”.
[0270] The third value “b 2 ” shows that the SPN from the reference location to the start location of R[2] as the third chunk is “b 2 ”.
[0271] The (n+1) th value “bn” shows that the SPN from the reference location to the start location of R[n] as the last chunk is “bn”.
[0272] When the data read out from the optical disc 2 is supplied, the separation part 51 separates data for the SPN corresponding to b 1 of the supplied data as R[0] based on the description of the two chunk_map( ) as shown in the bottom part of FIG. 29 . When the ilvt file of “00001.ilvt” is designated as a readout file, the respective data in the order of R[0], L[0], R[1], L[1], . . . , R[n], L[n] are supplied to the separation part 51 .
[0273] Further, the separation part 51 separates the data for the SPN corresponding to a 1 from the end location of R[0] as L[0] and separates the data for the SPN corresponding to b 2 -b 1 from the end location of L[0] as R[1]. The separation part 51 separates the data for the SPN corresponding to a 2 -a 1 from the end location of R[1] as L[1].
[0274] Similarly, the separation part 51 separates the data for the SPN corresponding to a value obtained by subtracting the value of bn from the value of the number_of_source_packets 2 described in the clpi file of “00002.clpi” from the end location of L[n-1] as R [n]. The separation part 51 separates the data for the SPN corresponding to a value obtained by subtracting the value of an from the value of the number_of_source_packets 1 described in the clpi file of “00001.clpi” from the end location of R[n] as L[n].
[0275] In this manner, the separation of the data by the separation part 51 is performed using the information of the lengths of the respective chunks described in the chunk_map( ).
[0276] Note that, when a value other than “1” is set for the MVC_file_type, the chunk_map( ) is optional. The player loading the PlayList in which a value other than “1” is set for the MVC_file_type should ignore the chunk_map( ) when the chunk_map( ) is in the PlayList.
[0277] When MVC_file_type=1, the corresponding two streams of the L video stream and the R video stream are divided into chunks in the same numbers, respectively. Regarding the interleaved R[i], L[i], the chunk of the L video stream and the chunk of the R video stream with the same values of index “i” have the same reproduction time.
[0278] FIG. 30 shows a syntax of EP_map( ) described in a clpi file.
[0279] EP_map( ) is referred to for specifying the decode start location when random access is made. The number_of_EP_entries indicates the number of EPs (entry points).
[0280] The description after the number_of_EP_entries is prepared for each EP. PTS_EP_start[i] indicates the PTS of EP and SPN_EP_start[i] indicates SPN of EP. In this manner, in the EP_map, the PTS and the SPN with respect to each entry point are registered in correspondence with each other. When the EP is designated, the readout start address is specified based on the PTS_EP_start[i] and SPN_EP_start[i] of the designated EP, and readout of files is performed.
Specific Example 2 of PlayList File
[0281] FIGS. 31A shows another specific example of the PlayList file.
[0282] The PlayList in FIG. 31A is a PlayList that controls 3D reproduction when the L video stream and the R video stream are contained in the same TS. That is, the m2ts file of the L video stream and the m2ts file of the R video stream are not interleaved on the optical disc 2 .
[0283] In this case, MVC_flag=1 as shown in the AppInfoPlayList( ) in FIG. 31A , and MVC_file_type=0 as shown in the PlayItem( ).
[0284] The Clip_Information_file_name of the PlayItem( ) is “00001”. From the description, the clpi file forming the Clip of the L video is specified. Further, from the IN_time and the OUT_time of the PlayItem( ) the start location and the end location of the reproduction section of the PlayItem are respectively specified, and, from the STN_table( ), the PID of the transport packet forming the L video stream is specified.
[0285] From the STN_table extension( ) of the ExtensionData( ), the PID of the transport packet forming the R video stream is specified. In the case of the example, the value of the type of the STN_table_extension( ) is “1”.
[0286] FIG. 31B shows a syntax of the clpi file of “00001.clpi”. As shown in FIG. 31B , the clpi file of “00001.clpi” contains EP_map. A value other than “1” is set for the MVC_file_type, and, in this example, the clpi file contains no chunk_map( ).
[0287] FIG. 32 shows a concept of file management performed based on the files in FIGS. 31A and 31B .
[0288] As shown in FIG. 32 , one TS containing the L video stream and the R video stream is managed using the m2ts file of “00001.m2ts”.
[0289] When the m2ts file of “00001.m2ts” is designated as a readout file by the application, the recording location of the m2ts file of “00001.m2ts” is specified by the UDF file system and read out by the disk drive 32 . The respective transport packets forming the L video stream and the R video stream contained in the m2ts file of “00001.m2ts” are respectively separated based on the PID.
Example 2 of Reproduction Processing
[0290] Processing of 3D reproduction performed according to the PlayList files in FIGS. 31A and 31B will be explained with reference to a flowchart in FIG. 33 .
[0291] At step S 21 , the controller 31 specifies the PID of the transport packet of the Main TS forming the L video stream from the description of the STN_table( ).
[0292] At step S 22 , the controller 31 specifies the PID of the transport packet of the Main TS forming the R video stream from the description of the STN_table_extension( ).
[0293] At step S 23 , the controller 31 specifies the file name of the clpi file corresponding to the m2ts file containing the L video stream and the R video stream as “00001.clpi” from the Clip_Information_file_name in the PlayItem( ) MVC_flag=1 and MVC_file_type=0, and thus, one Main TS containing the L video stream and the R video stream is specified.
[0294] At step S 24 , the controller 31 uses “00001.m2ts” as a readout file and allows the disk drive 32 to read out it from the optical disc 2 through the UDF file system. The data of the m2ts file of “00001.m2ts” read out from the disk drive 32 is supplied to the read buffer 52 via the separation part 51 and stored therein.
[0295] From the data stored in the read buffer 52 , the transport packet of the L video stream is extracted by the PID filter 53 based on the PID specified at step S 21 . The data of the extracted transport packet is supplied to the decoder 60 via the ES buffer 54 and the switch 59 .
[0296] Further, from the data stored in the read buffer 52 , the transport packet of the R video stream is extracted by the PID filter 53 based on the PID specified at step S 22 . The data of the extracted transport packet is supplied to the decoder 60 via the switch 57 , the ES buffer 58 , and the switch 59 .
[0297] At step S 25 , the decoder 60 decodes (reproduces) the packets sequentially supplied from the switch 59 .
[0298] 3D reproduction when the L video stream and the R video stream are contained in the same TS is performed in the above described manner.
Specific Example 3 of PlayList File
[0299] FIG. 34 shows yet another specific example of the PlayList file.
[0300] The PlayList in FIG. 34 is a PlayList that controls 3D reproduction when the TS containing the L video stream is recorded in the optical disc 2 and the TS containing the R video stream is recorded in the local storage 34 . For example, when the R video stream is downloaded from the server 22 , the PlayList recorded in the optical disc 2 is updated by adding information on the R video stream, and recorded in the local storage 34 and managed by the controller 31 .
[0301] MVC_flag=1 as shown in the AppInfoPlayList( ) in FIG. 34 , and MVC_file_type=2 as shown in the PlayItem( ).
[0302] The Clip_Information_file_name of the PlayItem( ) is “00001”. From the description, the clpi file forming the Clip of the L video is specified. Further, from the IN_time and the OUT_time of the PlayItem( ) the start location and the end location of the reproduction section of the PlayItem are respectively specified, and, from the STN_table( ), the PID of the transport packet forming the L video stream is specified.
[0303] In the ExtensionData( ) information on the SubPath referring to the R video stream is described. In this example, also, the normal number of SubPaths is “0” (the value of the number_of_SubPaths (on the 14th line in FIG. 11 ) is “0”), and SubPath_id=0 is assigned to the SubPath referring to the R video stream. As shown in FIG. 34 , in the SubPath_extension( ), SubPath_type_extension=8 indicating the SubPath referring to the R video stream is set.
[0304] The Clip_Information_file_name of the SubPlayItem( ) of the ExtensionData( ) is “00003”. From the description, the clpi file forming the Clip of the R video is specified. Also, the clpi file of “00003.clpi” has been downloaded from the server 22 together with the m2ts file of “00003.m2ts” as the file of the corresponding R video stream and stored in the local storage 34 .
[0305] Further, from the SubPlayItem_IN_time and the SubPlayItem_OUT_time of the SubPlayItem( ) of the ExtensionData( ), the start location and the end location of the reproduction section of the SubPlayItem are respectively specified. From the STN_table_extension( ), the ID “0” of the SubPath referring to the R video stream (ref_to_SubPath_id=0) and the PID of the transport packet forming the R video stream (ref_to_R_video_PID) are specified. In the case of this example, the value of the type of the STN_table_extension( ) is “2”.
[0306] FIGS. 35A and 35B show syntaxes of clpi files.
[0307] FIG. 35A shows an example of the clpi file of “00001.clpi”. As shown in FIG. 35A , the clpi file of “00001.clpi” contains EP_map. FIG. 35B shows an example of the clpi file of “00003.clpi”. As shown in FIG. 35B , the clpi file of “00003.clpi” also contains EP_map.
[0308] For example, the EP_map contained in the clpi file of “00001.clpi” and the EP_map contained in the clpi file of “00003.clpi” contain information of EPs respectively set at the same time with reference to the initial time t 0 of the contents. The location of the L video stream for which reproduction is started using the EP_map contained in the clpi file of “00001.clpi” and the location of the R video stream for which reproduction is started using the EP_map contained in the clpi file of “00003.clpi” are locations at the same time on the time axis with reference to the time t 0 .
[0309] FIG. 36 shows a concept of file management performed using the files of FIGS. 34 , 35 A, and 35 B.
[0310] As shown in FIG. 36 , the TS containing the L video stream recorded in the optical disc 2 is managed using the m2ts file of “00001.m2ts”. Further, the TS containing the R video stream recorded in the local storage 34 is managed using the m2ts file of “00003.m2ts”.
[0311] In a BD, the data recorded in the BD and the data recorded in the local storage are managed using a virtual file system formed by merging the UDF file system that manages the data recorded in the BD, for example, and the file system that manages the data recorded in the local storage. A player containing the local storage generates the virtual file system and manages the data recorded in the BD and the data recorded in the local storage.
[0312] When the file to be read out is designated by an application, whether the file is recorded in the BD or recorded in the local storage and the address indicating the recording location on the recording media are specified by the virtual file system and the file is read out from the specified address of the specified recording media.
[0313] For example, when the m2ts file of “00001.m2ts” is designated by the application, the m2ts file of “00001.m2ts” recorded in a predetermined location of the optical disc 2 is specified by the virtual file system and read out by the disk drive 32 .
[0314] Further, when the m2ts file of “00003.m2ts” is designated by the application, the m2ts file of “00003.m2ts” recorded in a predetermined location of the local storage 34 is specified by the virtual file system and read out.
Example 3 of Reproduction Processing
[0315] Processing of 3D reproduction performed according to the PlayList file in FIG. 34 will be explained with reference to a flowchart in FIG. 37 .
[0316] At step S 41 , the controller 31 specifies the PID of the transport packet of the Main TS forming the L video stream from the description of the STN_table( ).
[0317] At step S 42 , the controller 31 specifies ref_to_SubPath_id=0 as the value of the SubPath_id of the SubPath referring to the R video stream and specifies the PID of the transport packet forming the R video stream from the description of the STN_table_extension( ).
[0318] At step S 43 , the controller 31 specifies the file name of the clpi file corresponding to the m2ts file of the Main TS containing the L video stream as “00001.clpi” from the Clip_Information_file_name in the PlayItem( ).
[0319] At step S 44 , the controller 31 specifies the file name of the clpi file corresponding to the m2ts file containing the R video stream as “00003.clpi” from the Clip_Information_file_name in the SubPlayItem( ) of the SubPath having SubPath_id=0 for which SubPath_type=8 is set in the SubPath_entries_extension( ).
[0320] At step S 45 , the controller 31 uses “00001.m2ts” as a readout file and allows the disk drive 32 to read out it from the optical disc 2 through the virtual file system.
[0321] At step S 46 , the controller 31 uses “00003.m2ts” as a readout file and reads out it from the local storage 34 through the virtual file system.
[0322] The data of the m2ts file of “00001.m2ts” read out by the disk drive 32 is supplied to the read buffer 52 via the separation part 51 and stored therein. The transport packet of the data of the L video stream stored in the read buffer 52 is extracted by the PID filter 53 based on the PID specified at step S 41 , and the data is supplied to the decoder 60 via the ES buffer 54 and the switch 59 .
[0323] On the other hand, the data of the m2ts file of “00003.m2ts” read out from the local storage 34 is supplied to the read buffer 55 via the separation part 51 and stored therein. The transport packet of the data of the R video stream stored in the read buffer 55 is extracted by the PID filter 56 based on the PID specified at step S 42 , and the data is supplied to the decoder 60 via the switch 57 , the ES buffer 58 , and the switch 59 .
[0324] At step S 47 , the decoder 60 decodes (reproduces) the packets sequentially supplied from the switch 59 .
[0325] 3D reproduction when the TS containing the L video stream is recorded in the optical disc 2 and the TS containing the R video stream is recorded in the local storage 34 is performed in the above described manner.
<Regarding Managed Copy>
Embodiment 1
[0326] Copying of 3D image contents (3D contents) recorded in the optical disc 2 in the local storage 34 using Managed Copy will be explained.
[0327] When the 3D contents recorded in the optical disc 2 are copied in the local storage 34 , authentication between the server 22 and the controller 31 of the reproducing device 1 is appropriately performed. The server 22 is an authentication server for the case where Managed Copy of the 3D contents recorded in the optical disc 2 is performed.
[0328] FIG. 38 shows a concept of file management of 3D contents to be copied.
[0329] As has been explained with reference to FIG. 25 etc., the management of the data recorded in the optical disc 2 is performed in the form of the three-layer structure of the physical layer, the file system layer, and the application layer.
[0330] The PlayList file # 1 shown in FIG. 38 as information of the application layer is the same as the PlayList file in FIG. 23 .
[0331] That is, the PlayList file # 1 is a PlayList file that controls 3D reproduction when the L video stream and the R video stream are contained in separate TS and the TS files (m2ts files) are interleaved and recorded in the optical disc 2 . The value of the MVC_flag is “1” and the value of the MVC_file_type is also “1”. In the ExtensionData( ) information on the SubPath referring to the R video stream is described.
[0332] Further, Clip Information files # 11 , # 12 shown in FIG. 38 are the same as the clpi file in FIG. 24A and the clpi file in FIG. 24B , respectively.
[0333] The Clip Information file # 11 is a clpi file forming the Clip of the L video. In the Clip Information file # 11 , number_of_source_packets 1 , EP_map, chunk_map( ) are contained. The number_of_source_packets 1 indicates the number of source packets contained in the m2ts file of “00001.m2ts”, and the EP_map of the Clip Information file # 11 contains a location of the entry point set for the m2ts file of “00001.m2ts”. The chunk_map( ) in the Clip Information file # 11 shows the locations of the respective chunks of the m2ts file of “00001.m2ts”.
[0334] The Clip Information file # 12 is a clpi file forming the Clip of the R video. In the Clip Information file # 12 , number_of_source_packets 2 , EP_map, chunk_map( ) are contained.
[0335] The number_of_source_packets 2 indicates the number of source packets contained in the m2ts file of “00002.m2ts”, and the EP_map of the Clip Information file # 12 contains a location of the entry point set for the m2ts file of “00002.m2ts”. The chunk_map( ) in the Clip Information file # 12 shows the locations of the respective chunks of the m2ts file of “00002.m2ts”.
[0336] The respective m2ts files of “00001.m2ts”, “00002.m2ts” and the ilvt file of “00001.ilvt” shown as information of the file system layer in FIG. 38 are the same as the respective files in FIG. 25 .
[0337] The m2ts file of “00001.m2ts” is a file that manages the L video stream and the m2ts file of “00002.m2ts” is a file that manages the R video stream. The ilvt file of “00001.ilvt” is a file that manages the m2ts file of the L video stream and the m2ts file of the R video stream interleaved and recorded with respect to each predetermined data unit by the function of extent-sharing of the UDF file system.
[0338] When the m2ts file of the L video stream and the m2ts file of the R video stream are interleaved and recorded in the optical disc 2 , the L video stream and the R video stream are managed by the three files.
[0339] As shown in FIG. 38 as information of the physical layer, on the optical disc 2 , the chunks forming the L video stream and the chunks forming the R video stream are interleaved and recorded.
[0340] The case where the 3D contents having the management structure are copied in the local storage 34 will be explained. The file system supported by the local storage 34 is FAT (File Allocation Table), for example, and extent-sharing is not supported.
[0341] The case where “00001.m2ts”, “00002.m2ts”, “00001.ilvt” that may be specified based on the description of the PlayList file # 1 in the above described manner are read out from the optical disc 2 and copied in the local storage 34 will be considered.
[0342] In this case, as shown in FIG. 39 , in the local storage 34 , the L video stream managed by the m2ts file of “00001.m2ts” and the R video stream managed by the m2ts file of “00002.m2ts” are copied. Further, the interleaved L video, R video streams managed by the ilvt file of “00001.ilvt” are respectively copied. In the example of FIG. 39 , two clpi files of “00001.clpi”, “00002.clpi” are copied in correspondence with the two m2ts files of “00001.m2ts”, “00002.m2ts”, respectively.
[0343] As a result, given that the data volume of the L video stream and the R video stream interleaved and recorded in the optical disc 2 is 25 GB, data of 50 GB twice in the data volume is recorded in the local storage 34 .
[0344] The reason that the L video stream and the R video stream interleaved and recorded in the optical disc 2 is that it is necessary to alternately read out the L video data and the R video data coded with reference to the data for display of 3D images, and reading out of data is late for reproduction because seeking takes long time when the readout speed of the optical disc 2 is lower and the respective data are recorded in different regions in the manner that the entire R video stream is recorded after the entire L video stream.
[0345] The local storage 34 as an HDD or an SSD is a recording medium at the higher readout speed compared to that of the optical disc 2 , and, even when the L video stream and the R video stream are recorded in the respective different regions, the data may be read out in time for reproduction. The interleaved L video, R video streams copied with the ilvt file of “00001.ilvt” designated as the readout file are regarded as wasteful data in view of the capacity of the local storage 34 .
[0346] In the reproducing device 1 , the wasteful data is not copied, but copying of 3D contents recorded in the optical disc 2 is efficiently be performed.
[0347] FIG. 40 is a block diagram showing a functional configuration example of the controller 31 .
[0348] As shown in FIG. 40 , in the controller 31 , a data acquisition part 71 , an information processing part 72 , a recording control part 73 , and a reproduction control part 74 are realized. At least a part of the functional part shown in FIG. 40 is realized when a predetermined program is executed by a CPU (Central Processing Unit, not shown) within the controller 31 . By the respective parts in FIG. 40 , copying of 3D contents recorded in the optical disc 2 and reproduction of the 3D contents copied in the local storage 34 are performed.
[0349] The data acquisition part 71 controls the disk drive 32 and reads out various kinds of data from the optical disc 2 . For example, the data acquisition part 71 reads out and acquires a certain PlayList file as reproduction control information of 3D contents to be copied from the optical disc 2 and outputs it to the information processing part 72 .
[0350] Further, the data acquisition part 71 reads out and outputs the clpi files of the Clips of the L video and R video to the information processing part 72 , and reads out and outputs the m2ts files of the Clips of the L video and R video to the recording control part 73 according to the control by the information processing part 72 .
[0351] The information processing part 72 determines whether or not the mt2s file of the L video stream and the mt2s file of the R video stream are interleaved in predetermined data units and recorded on the optical disc 2 based on the value of the MVC_file_type contained in the PlayList file supplied from the data acquisition part 71 .
[0352] As has been explained with reference to FIG. 13 , the value “1” of the MVC_file_type shows that the mt2s file of the L video stream and the mt2s file of the R video stream are interleaved and recorded on the optical disc 2 . The information processing part 72 determines that the mt2s file of the L video stream and the mt2s file of the R video stream are interleaved and recorded on the optical disc 2 when the value of the MVC_file_type is “1”. Further, the information processing part 72 determines that the files are not interleaved but recorded when the value of the MVC_file_type is a value other than “1”.
[0353] When determining that the mt2s file of the L video stream and the mt2s file of the R video stream are interleaved and recorded on the optical disc 2 , the information processing part 72 allows the data acquisition part 71 to respectively read out the mt2s file that manages the L video stream and the mt2s file that manages the R video stream. The mt2s files read out by the data acquisition part 71 are supplied to the recording control part 73 and recorded (copied) in the local storage 34 .
[0354] Further, the information processing part 72 deletes the chunk_map( ) from the clpi file corresponding to the m2ts file copied in the local storage 34 and outputs the clpi file from which the chunk_map( ) has been deleted to the recording control part 73 .
[0355] Furthermore, the information processing part 72 changes the value of the MVC_file_type from “1” to “2”, and outputs the PlayList file in which the value of the MVC_file_type has been changed to the recording control part 73 . The PlayList file in which the value of the MVC_file_type has been changed is used as reproduction control information of the stream copied in the local storage 34 .
[0356] The recording control part 73 records the mt2s file that manages the L video stream and the mt2s file that manages the R video stream supplied from the data acquisition part 71 in the local storage 34 . Further, the recording control part 73 records the PlayList file in which contents have been changed by the information processing part 72 and the clpi file from which the chunk_map( ) has been deleted in the local storage 34 .
[0357] When reproduction of the 3D contents copied in the local storage 34 is commanded, the reproduction control part 74 controls the reproduction of the copied 3D contents based on a new PlayList recorded in the local storage 34 . Note that the respective reproduction processing that have been explained with reference to FIGS. 26 , 33 , and 37 are performed by the reproduction control part 74 .
Example of Copy Processing
[0358] Here, processing of the reproducing device 1 of copying 3D contents in FIG. 38 recorded in the optical disc 2 in the local storage 34 will be explained with reference to a flowchart in FIG. 41 .
[0359] At step S 101 , the data acquisition part 71 reads out the PlayList file # 1 as the PlayList file of the 3D contents to be copied from the optical disc 2 . The PlayList file # 1 is acquired by the data acquisition part 71 and supplied to the information processing part 72 .
[0360] At step S 102 , the information processing part 72 recognizes reference to the ilvt file in the PlayList file # 1 based on the value “1” of the MVC_file_type. The reference to the ilvt file in the PlayList file means that the m2ts file of the L video stream and the m2ts file of the R video stream are interleaved and recorded in the optical disc 2 .
[0361] At step S 103 , the information processing part 72 specifies the file name of the clpi file corresponding to the m2ts file of the Main TS containing the L video stream as “00001.clpi” from the Clip_Information_file_name in the PlayItem( ). In the PlayList file # 1 , the Clip_Information_file_name of the PlayItem( ) is “00001”, and, from the description, the file name of the clpi file forming the Clip of the L video is specified in the above described manner.
[0362] At step S 104 , the information processing part 72 specifies the SubPath referring to the R video stream for which SubPath_id=0 and SubPath_type_extension=8 are set in the SubPath_entries_extension( ). Further, the information processing part 72 specifies the file name of the clpi file corresponding to the m2ts file containing the R video stream as “00002.clpi” from the Clip_Information_file_name in the SubPlayItem( ) of the specified SubPath.
[0363] At step S 105 , the data acquisition part 71 reads out the Clip Information files # 11 , # 12 from the optical disc 2 based on the file names specified by the information processing part 72 . The file name of the Clip Information file # 11 is “00001.clpi” and the file name of the Clip Information file # 12 is “00002.clpi”.
[0364] At step S 106 , the information processing part 72 specifies “00001.ilvt” containing the same five characters as the number (00001) contained in the file names of the files (m2ts files, clpi files) forming the Clip of the L video with extension of ilvt. Here, the ilvt file with the specified file name is handled as a file not to be copied.
[0365] At step S 107 , the information processing part 72 controls the data acquisition part 71 to designate “00001.m2ts” containing the same five characters as the number contained in “00001.clpi” with extension of m2ts as a readout file and read out it from the optical disc 2 . The recording control part 73 copies the m2ts file of “00001.m2ts” read out from the data acquisition part 71 , i.e., the L video stream in the local storage 34 .
[0366] At step S 108 , the information processing part 72 controls the data acquisition part 71 to designate “00002.m2ts” containing the same five characters as the number contained in “00002.clpi” with extension of m2ts as a readout file and read out it from the optical disc 2 . The recording control part 73 copies the m2ts file of “00002.m2ts” read out from the data acquisition part 71 , i.e., the R video stream in the local storage 34 .
[0367] At step S 109 , the information processing part 72 deletes the chunk_map( ) from the clpi file of “00001.clpi” read out at step S 105 and outputs it as a new Clip Information file # 11 to the recording control part 73 . The recording control part 73 copies the new Clip Information file # 11 supplied from the information processing part 72 in the local storage 34 .
[0368] At step S 110 , the information processing part 72 deletes the chunk_map( ) from the clpi file of “00002.clpi” read out at step S 105 and outputs it as a new Clip Information file # 12 to the recording control part 73 . The recording control part 73 copies the new Clip Information file # 12 supplied from the information processing part 72 in the local storage 34 .
[0369] At step S 111 , the information processing part 72 changes the value of the MVC_file_type of the PlayList file # 1 from “1” to “2”, and outputs it as a new PlayList file # 1 to the recording control part 73 . The recording control part 73 copies the new PlayList file # 1 supplied from the information processing part 72 in the local storage 34 .
[0370] FIG. 42 shows the PlayList file # 1 in which the value of MVC_file_type has been changed.
[0371] As shown by an underline, the value of the MVC_file_type is changed from “1” to “2” by the information processing part 72 . As has been explained with reference to FIG. 13 , the value “2” of the MVC_file_type shows that both or one of the m2ts file of the L video stream and the m2ts file of the R video stream is recorded in the local storage 34 .
[0372] The PlayList # 1 containing the description in FIG. 42 is recorded in the local storage 34 together with the m2ts file that manages the L video stream and the m2ts file that manages the R video stream, and used as reproduction control information for the copied 3D contents.
[0373] FIG. 43 shows Clip Information files # 11 , # 12 from which chunk_map( ) has been deleted.
[0374] As shown in FIG. 43 , the chunk_map( ) respectively contained in the Clip Information files # 11 , # 12 are deleted by the information processing part 72 . The Clip Information file # 11 containing the description in FIG. 43 is recorded as the clpi file forming the Clip of the L video in correspondence with the m2ts file that manages the L video stream in the local storage 34 . Further, the Clip Information file # 12 containing the description in FIG. 43 is recorded as the clpi file forming the Clip of the R video in correspondence with the m2ts file that manages the R video stream in the local storage 34 .
[0375] FIG. 44 shows a status of the local storage 34 after copying.
[0376] In the local storage 34 after copying is performed by the processing in FIG. 41 , the L video stream managed by the m2ts file of “00001.m2ts” and the R video stream managed by the m2ts file of “00002.m2ts” are recorded. Further, the clpi file of “00001.clpi” (Clip Information file # 11 ) is recorded in correspondence with the m2ts file of “00001.m2ts” and the clpi file of “00002.clpi” (Clip Information file # 12 ) is recorded in correspondence with the m2ts file of “00002.m2ts”.
[0377] Also, the PlayList file # 1 is recorded in the local storage 34 . As shown in FIG. 44 , the interleaved and recorded L video stream and R video stream managed by the ilvt file of “00001.ilvt” are not copied.
[0378] In this manner, copying may efficiently be performed by copying only the L video stream and the R video stream managed by the m2ts files but not copying the streams interleaved and recorded in the optical disc 2 . Given that the entire data volume of the L video stream and the R video stream interleaved and recorded in the optical disc 2 is 25 GB, data in the same volume is recorded in the local storage 34 .
[0379] Further, the copied 3D contents may be reproduced based on the information after change by changing contents of the PlayList file and the clpi files. As has been explained with reference to FIGS. 28A to 29 , the chunk_map( ) contained in the clpi files are used for reading out of the interleaved and recorded data. In the local storage 34 , the L video stream and the R video stream are not interleaved but recorded, the chunk_map( ) is unnecessary information and deleted from the clpi files at copying.
Example of Reproduction Processing of Copied 3D Contents
[0380] Processing of the reproducing device 1 of reproducing the 3D contents copied in the local storage 34 by the processing in FIG. 44 will be explained with reference to FIG. 45 .
[0381] At step S 121 , the reproduction control part 74 reads out the PlayList file # 1 (the PlayList file # 1 in FIG. 42 ) of the 3D contents to be reproduced from the local storage 34 .
[0382] At step S 122 , the reproduction control part 74 recognizes that the mt2s file of the R video stream is another file than the mt2s file of the L video stream based on the value “2” of the MVC_file_type of the PlayList file # 1 .
[0383] At step S 123 , the reproduction control part 74 specifies the PID of the transport packet of the TS containing the L video stream from the description of the STN_table( ). This processing corresponds to the processing at step S 1 in FIG. 26 , for example.
[0384] At step S 124 , the reproduction control part 74 specifies the ref_to_SubPath_id=0 as the ID of the SubPath referring to the R video stream from the description of the STN_table_extension( ) and specifies the PID of the transport packet of the TS containing the R video stream. This processing corresponds to the processing at step S 2 in FIG. 26 , for example.
[0385] At step S 125 , the reproduction control part 74 specifies the file name of the clpi file corresponding to the m2ts file of the Main TS containing the L video stream as “00001.clpi” from the Clip_Information_file_name in the PlayItem( ). This processing corresponds to the processing at step S 3 in FIG. 26 , for example.
[0386] At step S 126 , the reproduction control part 74 specifies the SubPath for which SubPath_id=0 is set and SubPath_type=8 is set in the SubPath_entries_extension( ). Further, the reproduction control part 74 specifies the file name of the clpi file corresponding to the m2ts file containing the R video stream as “00002.clpi” from the Clip_Information_file_name in the SubPlayItem( ) of the specified SubPath. This processing corresponds to the processing at step S 4 in FIG. 26 , for example.
[0387] At step S 127 , the reproduction control part 74 reads out the Clip Information files # 11 and # 12 from the local storage 34 based on the specified file names. From the Clip Information files # 11 and # 12 , the chunk_map( ) has been deleted as shown in FIG. 43 .
[0388] At step S 128 , the reproduction control part 74 reads out the m2ts file of “00001.m2ts” containing the same five characters as the number contained in “00001.clpi” with extension of m2ts, i.e., the L video stream from the local storage 34 .
[0389] At step S 129 , the reproduction control part 74 reads out the m2ts file of “00002.m2ts” containing the same five characters as the number contained in “00002.clpi” with extension of m2ts, i.e., the R video stream from the local storage 34 .
[0390] At step S 130 , the reproduction control part 74 outputs the streams read out from the local storage 34 to the decode unit 36 for reproduction. The reproduction of the streams read out from the local storage 34 is performed in the same manner as the above described processing.
[0391] That is, the data of the L video stream supplied to the decode unit 36 is output to the read buffer 52 via the separation part 51 in FIG. 22 and the data of the R video stream is output to the read buffer 55 .
[0392] The transport packet of the L video stream stored in the read buffer 52 is extracted by the PID filter 53 based on the PID specified at step S 123 , and supplied to the decoder 60 via the ES buffer 54 and the switch 59 . The transport packet of the R video stream stored in the read buffer 55 is extracted by the PID filter 56 based on the PID specified at step S 124 , and supplied to the decoder 60 via the switch 57 , the ES buffer 58 , and the switch 59 .
[0393] In the decoder 60 , the packets sequentially supplied from the switch 59 are decoded and reproduction of the L video streams and the R video streams is performed.
[0394] The reproduction of the 3D contents copied from the optical disc 2 in the local storage 34 is performed in the above described manner.
Embodiment 2
[0395] In the above description, whether or not the mt2s file of the L video stream and the mt2s file of the R video stream are interleaved and recorded in the optical disc 2 has been determined based on the value of the MVC_file_type, however, that may be determined based on other information.
[0396] FIG. 46 is another diagram showing the concept of file management of 3D contents to be copied.
[0397] In a PlayList file # 21 in FIG. 46 , whether or not the mt2s file of the L video stream and the mt2s file of the R video stream are interleaved and recorded in the optical disc 2 is shown by the SubPath_type_extension contained in the ExtensionData( ). As shown in FIG. 46 , the PlayList file # 21 contains no MVC_file_type. Further, the file contains no MVC_flag.
[0398] The PlayList file # 21 in FIG. 46 is the same as the PlayList file # 1 in FIG. 38 except that no MVC_file_type or MVC_flag is contained.
[0399] In this case, meanings of the values of the SubPath_type_extension are as shown in FIG. 47 .
[0400] As shown in FIG. 47 , the meanings of the values of the SubPath_type_extension are basically the same as the meanings of the respective values that have been explained with reference to FIG. 17 , and the meaning shown by an underline is added as the meaning of SubPath_type_extension=8.
[0401] That is, SubPath_type_extension=8 in the PlayList file # 21 with no MVC_file_type shows that the SubPath for which SubPath_type_extension=8 is set is SubPath referring to the R video stream. Further, it shows that the m2ts file of the R video stream referred to is another file than the m2ts file of the L video stream referred to by the PlayItem. Furthermore, it shows that the m2ts file of the R video stream and the m2ts file of the R video stream are interleaved and recorded in the optical disc 2 .
[0402] The reproducing device 1 may determine whether or not the mt2s file of the L video stream and the mt2s file of the R video stream are interleaved and recorded in the optical disc 2 from the value of the SubPath_type_extension.
[0403] Further, the meanings of the values of the normal SubPath_type contained in the subPath( ) field (from the 34th line to the 40th line in FIG. 11 ) are as shown in FIG. 48 .
[0404] As shown in FIG. 48 , the meanings of the values of the SubPath_type are basically the same as the meanings of the respective values that have been explained with reference to FIG. 14 , and the meaning shown by an underline is added as the meaning of SubPath_type=5.
[0405] That is, SubPath_type=5 in the PlayList file # 21 with no MVC_file_type shows that the SubPath for which SubPath_type=5 is set is SubPath referring to the R video stream. Further, it shows that the m2ts file of the L video stream referred to by the PlayItem is another file than the m2ts file of the R video stream and the m2ts file of the R video stream is supplied from the local storage.
[0406] The meanings of the values of SubPath_type=0 to 7 are also used as meanings of the values of SubPath_type_extension=0 to 7.
[0407] Returning to the explanation of FIG. 46 , Clip Information files # 31 and # 32 in FIG. 46 are the same as the Clip Information files # 11 and # 12 in FIG. 38 . Further, the contents of the file system layer and the physical layer shown in FIG. 46 are the same as the contents shown in FIG. 38 .
Example 1 of Copy Processing
[0408] Here, processing of the reproducing device 1 of copying the 3D contents in FIG. 46 recorded in the optical disc 2 in the local storage 34 will be explained with reference to a flowchart in FIG. 49 .
[0409] At step S 141 , the data acquisition part 71 reads out the PlayList file # 21 as the PlayList file of the 3D contents to be copied from the optical disc 2 . The PlayList file # 21 is acquired by the data acquisition part 71 and supplied to the information processing part 72 .
[0410] At step S 142 , the information processing part 72 recognizes reference to the ilvt file based on the value “8” of the SubPath_type_extension of the PlayList file # 21 .
[0411] At step S 143 , the information processing part 72 specifies the file name of the clpi file corresponding to the m2ts file of the Main TS containing the L video stream as “00001.clpi” from the Clip_Information_file_name in the PlayItem( ).
[0412] At step S 144 , the information processing part 72 specifies the SubPath for which SubPath_id=0 is set and SubPath_type=8 is set in the SubPath_entries_extension( ). Further, the information processing part 72 specifies the file name of the clpi file corresponding to the m2ts file containing the R video stream as “00002.clpi” from the Clip_Information_file_name in the SubPlayItem( ) of the specified SubPath.
[0413] At step S 145 , the data acquisition part 71 reads out the Clip Information files # 31 and # 32 from the optical disc 2 based on the file names specified by the information processing part 72 .
[0414] At step S 146 , the information processing part 72 specifies “00001.ilvt” containing the same five characters as the number (00001) contained in the file forming the Clip of the L video with extension of ilvt.
[0415] At step S 147 , the information processing part 72 controls the data acquisition part 71 to designate “00001.m2ts” containing the same five characters as the number contained in “00001.clpi” with extension of m2ts as a readout file and read out it from the optical disc 2 . The recording control part 73 copies the m2ts file of “00001.m2ts” read out by the data acquisition part 71 , i.e., the L video stream in the local storage 34 .
[0416] At step S 148 , the information processing part 72 controls the data acquisition part 71 to designate “00002.m2ts” containing the same five characters as the number contained in “00002.clpi” with extension of m2ts as a readout file and read out it from the optical disc 2 . The recording control part 73 copies the m2ts file of “00002.m2ts” read out by the data acquisition part 71 , i.e., the R video stream in the local storage 34 .
[0417] At step S 149 , the information processing part 72 deletes the chunk_map( ) from the clpi file of “00001.clpi” read out at step S 145 and outputs it to the recording control part 73 as a new Clip Information file # 31 . The recording control part 73 copies the new Clip Information file # 31 supplied from the information processing part 72 in the local storage 34 .
[0418] At step S 150 , the information processing part 72 deletes the chunk_map( ) from the clpi file of “00002.clpi” read out at step S 145 and outputs it as a new Clip Information file # 32 to the recording control part 73 . The recording control part 73 copies the new Clip Information file # 32 supplied from the information processing part 72 in the local storage 34 .
[0419] At step S 151 , the information processing part 72 changes the value of the SubPath_type_extension contained in the field of the ExtensionData( ) of the PlayList file # 21 from “8” to “5”, and outputs it as a new PlayList file # 21 to the recording control part 73 . The recording control part 73 copies the new PlayList file # 21 supplied from the information processing part 72 in the local storage 34 .
[0420] FIG. 50 shows the PlayList file # 21 in which the value of SubPath_type_extension( ) has been changed.
[0421] As shown by an underline, the value of the SubPath_type_extension is changed from “8” to “5” by the information processing part 72 . The PlayList file # 21 containing the description in FIG. 50 is recorded together with the m2ts file that manages the L video stream and the m2ts file that manages the R video stream in the local storage 34 , and used as reproduction control information for the copied 3D contents.
[0422] FIG. 51 shows Clip Information files # 31 and # 32 from which chunk_map( ) has been deleted. The Clip Information files # 31 and # 32 shown in FIG. 51 are the same as the Clip Information files # 11 and # 12 shown in FIG. 43 , respectively.
[0423] The state of the local storage 34 after copying is performed by the processing in FIG. 49 is the same as the status shown in FIG. 44 .
[0424] That is, in the local storage 34 , the L video stream managed by “00001.m2ts” and the R video stream managed by “00002.m2ts” are recorded. Further, the clpi file of “00001.clpi” (Clip Information file # 31 ) is recorded in correspondence with the m2ts file of “00001.m2ts” and the clpi file of “00002.clpi” (Clip Information file # 32 ) is recorded in correspondence with the m2ts file of “00002.m2ts”.
[0425] Thereby, whether or not the mt2s file of the L video stream and the mt2s file of the R video stream are interleaved and recorded in the optical disc 2 may be determined based on the SubPath_type_extension( ) and copying may efficiently be performed.
Example 1 of Reproduction Processing of Copied 3D contents
[0426] Processing of the reproducing device 1 of reproducing the 3D contents copied by the processing in FIG. 49 in the local storage 34 will be explained with reference to a flowchart in FIG. 52 .
[0427] At step S 161 , the reproduction control part 74 reads out the PlayList file # 21 (the PlayList file # 21 in FIG. 50 ) of the 3D contents to be reproduced from the local storage 34 .
[0428] At step S 162 , the reproduction control part 74 recognizes that the m2ts file of the R video stream is another file than the m2ts file of the L video stream based on the value “5” of the SubPath_type_extension of the PlayList file # 21 .
[0429] At step S 163 , the reproduction control part 74 specifies the PID of the transport packet of the TS containing the L video stream from the description of the STN_table( ).
[0430] At step S 164 , the reproduction control part 74 specifies the ref_to_SubPath_id=0 as the ID of the SubPath referring to the R video stream, and specifies the PID of the transport packet of the TS containing the R video stream from the description of the STN_table_extension( ).
[0431] At step S 165 , the reproduction control part 74 specifies the file name of the clpi file corresponding to the m2ts file of the TS containing the L video stream as “00001.clpi” from the Clip_Information_file_name in the PlayItem( ).
[0432] At step S 166 , the reproduction control part 74 specifies the SubPath for which SubPath_id=0 is set and SubPath_type=8 is set in the SubPath_entries_extension( ). Further, the part specifies the file name of the clpi file corresponding to the m2ts file of the TS containing the R video stream as “00002.clpi” from the Clip_Information_file_name in the SubPlayItem( ) of the specified SubPath.
[0433] At step S 167 , the reproduction control part 74 reads out the Clip Information files # 31 and # 32 from the local storage 34 based on the specified file names. From the Clip Information files # 31 and # 32 , the chunk_map( ) has been deleted as shown in FIG. 51 .
[0434] At step S 168 , the reproduction control part 74 reads out the m2ts file of “00001.m2ts” containing the same five characters as the number contained in “00001.clpi” with extension of m2ts, i.e., the L video stream from the local storage 34 .
[0435] At step S 169 , the reproduction control part 74 reads out the m2ts file of “00002.m2ts” containing the same five characters as the number contained in “00002.clpi” with extension of m2ts, i.e., the R video stream from the local storage 34 .
[0436] At step S 170 , the reproduction control part 74 outputs the streams read out from the local storage 34 to the decode unit 36 for reproduction. The reproduction of the streams read out from the local storage 34 is performed in the same manner as the processing at step S 131 in FIG. 45 .
Example 2 of Copy Processing
[0437] As the change made to the PlayList file # 21 at copying, the change of the value of the SubPath_type_extension( ) has been made in the processing in FIG. 49 , however, a change of shifting the description of the SubPath_extension( ) from the field of ExtensionData( ) to the field of SubPath( ) may be made.
[0438] As the description on the SubPath referring to the R video stream, the STN_table_extension( ) of the SubPath_entries_extension( ) and the STN_table_extension( ) contained in the field of the ExtensionData( ) is described in the field of ExtensionData( ) without change.
[0439] In the explanation with reference to FIG. 11 , information of the SubPath_extension( ) in the SubPath_entries_extension( ) on the 47th line ( FIG. 16 ) is shifted as information within the SubPath( ) from the 34th line to the 40th line. The PlayList file # 21 in which contents have been changed in this manner is recorded as a new PlayList file # 21 in the local storage 34 .
[0440] Other processing of the reproducing device 1 of copying 3D contents in FIG. 46 recorded in the optical disc 2 in the local storage 34 will be explained with reference to a flowchart in FIG. 53 .
[0441] In the processing in FIG. 53 , the PlayList file # 21 in which the information within the SubPath_extension( ) is rewritten as information within the SubPath( ) is copied. The processing in FIG. 53 is the same processing as the processing that has been explained with reference to FIG. 49 except that the contents rewritten in the PlayList file # 21 are different.
[0442] At step S 181 , the data acquisition part 71 reads out the PlayList file # 21 as the PlayList file of the 3D contents to be copied from the optical disc 2 .
[0443] At step S 182 , the information processing part 72 recognizes reference to the ilvt file based on the value “8” of the SubPath_type_extension in the PlayList file # 21 .
[0444] At step S 183 , the information processing part 72 specifies the file name of the clpi file corresponding to the m2ts file of the Main TS containing the L video stream as “00001.clpi” from the Clip_Information_file_name in the PlayItem( ) of the PlayList file # 21 .
[0445] At step S 184 , the information processing part 72 specifies the SubPath for which SubPath_id=0 is set and SubPath_type=8 is set in the SubPath_entries_extension( ) Further, the information processing part 72 specifies the file name of the clpi file corresponding to the m2ts file containing the R video stream as “00002.clpi” from the Clip_Information_file_name in the SubPlayItem( ) of the specified SubPath.
[0446] At step S 185 , the data acquisition part 71 reads out the Clip Information files # 31 , # 32 from the optical disc 2 .
[0447] At step S 186 , the information processing part 72 specifies “00001.ilvt” containing the same five characters as the number (00001) contained in the file name of the files forming the Clip of the L video with extension of ilvt.
[0448] At step S 187 , the information processing part 72 controls the data acquisition part 71 to designate “00001.m2ts” containing the same five characters as the number contained in “00001.clpi” with extension of m2ts as a readout file and read out it from the optical disc 2 . The recording control part 73 copies the m2ts file of “00001.m2ts” read out from the data acquisition part 71 , i.e., the L video stream in the local storage 34 .
[0449] At step S 188 , the information processing part 72 controls the data acquisition part 71 to designate “00002.m2ts” containing the same five characters as the number contained in “00002.clpi” with extension of m2ts as a readout file and read out it from the optical disc 2 . The recording control part 73 copies the m2ts file of “00002.m2ts” read out from the data acquisition part 71 , i.e., the R video stream in the local storage 34 .
[0450] At step S 189 , the information processing part 72 deletes the chunk_map( ) from the clpi file of “00001.clpi” read out at step S 185 and outputs it as a new Clip Information file # 31 to the recording control part 73 . The recording control part 73 copies the new Clip Information file # 31 supplied from the information processing part 72 in the local storage 34 .
[0451] At step S 190 , the information processing part 72 deletes the chunk_map( ) from the clpi file of “00002.clpi” read out at step S 185 and outputs it as a new Clip Information file # 32 to the recording control part 73 . The recording control part 73 copies the new Clip Information file # 32 supplied from the information processing part 72 in the local storage 34 .
[0452] At step S 191 , the information processing part 72 changes the value of the SubPath_type_extension of the PlayList file # 21 from “8” to “5”. Further, the information processing part 72 describes the description of the SubPath_extension( ) within the ExtensionData( ) and outputs it as a new PlayList file # 21 to the recording control part 73 . The recording control part copies the new PlayList file # 21 supplied from the information processing part 72 in the local storage 34 .
[0453] FIG. 54 shows the PlayList file # 21 in which the location of the description of SubPath_extension( ) has been changed.
[0454] As shown by an underline, the value of the SubPath_type is set to “5” by the information processing part 72 . Further, the description of the SubPlayItem( ) described in the SubPath_extension( ) is described within the SubPath( ). The SubPlayItem( ) within the SubPath( ) contains the file name of the clpi file corresponding to the R video stream referred to by the SubPlayItem, the SubPlayItem_IN_time indicating the start location of the reproduction section, and the SubPlayItem_OUT_time indicating the end location.
[0455] The PlayList file # 21 containing the description in FIG. 54 is recorded in the local storage 34 together with the mt2s file that manages the L video stream and the mt2s file that manages the R video stream, and used as reproduction control information for the copied 3D contents.
[0456] The Clip Information files # 31 and # 32 copied in the local storage 34 are the same as the Clip Information files # 11 and # 12 shown in FIG. 51 .
Example 2 of Reproduction Processing of Copied 3D Contents
[0457] Processing of the reproducing device 1 of copying 3D contents copied by the processing in FIG. 53 in the local storage 34 will be explained with reference to a flowchart in FIG. 55 .
[0458] At step S 201 , the reproduction control part 74 reads out the PlayList file # 21 (the PlayList file # 21 in FIG. 54 ) to be reproduced from the local storage 34 .
[0459] At step S 202 , the reproduction control part 74 recognizes that the m2ts file of the R video stream is another file than the m2ts file of the L video stream based on the value “5” of the SubPath_type of the PlayList file # 21 .
[0460] As has been explained with reference to FIG. 48 , the value “5” of the SubPath_type shows that the m2ts file of the R video stream referred to by the PlayItem is another file than the m2ts file of the L video stream, and the m2ts file of the R video stream is supplied from the local storage.
[0461] The processing from steps S 203 to S 210 is the same processing as the processing from steps S 163 to S 170 in FIG. 52 . At step S 203 , the reproduction control part 74 specifies the PID of the transport packet of the TS containing the R video stream from the description of the STN_table( ).
[0462] At step S 204 , the reproduction control part 74 specifies the ref_to_SubPath_id=0 as the ID of the SubPath referring to the R video stream, and specifies the PID of the transport packet of the TS containing the R video stream from the description of the STN_table extension( ).
[0463] At step S 205 , the reproduction control part 74 specifies the file name of the clpi file corresponding to the m2ts file of the TS containing the L video stream as “00001.clpi” from the Clip_Information_file_name in the PlayItem( ).
[0464] At step S 206 , the reproduction control part 74 specifies the SubPath for which SubPath_id=0 is set and SubPath_type=5 is set in the SubPath( ). Further, the reproduction control part 74 specifies the file name of the clpi file corresponding to the m2ts file containing the R video stream as “00002.clpi” from the Clip_Information_file_name in the SubPlayItem( ) of the specified SubPath.
[0465] At step S 207 , the reproduction control part 74 reads out the Clip Information files # 31 and # 32 from the local storage 34 based on the specified filenames. From the Clip Information files # 31 and # 32 , the chunk_map( ) has been deleted.
[0466] At step S 208 , the reproduction control part 74 reads out the m2ts file of “00001.m2ts” containing the same five characters as the number contained in “00001.clpi” with extension of m2ts, i.e., the L video stream from the local storage 34 .
[0467] At step S 209 , the reproduction control part 74 reads out the m2ts file of “00002.m2ts” containing the same five characters as the number contained in “00002.clpi” with extension of m2ts, i.e., the R video stream from the local storage 34 .
[0468] At step S 210 , the reproduction control part 74 outputs the streams read out from the local storage 34 to the decode unit 36 for reproduction.
Configuration Example of Computer
[0469] The above described series of processing may be executed using hardware or software. When the series of processing is executed using software, a program forming the software is installed from a program recording medium into a computer incorporated into dedicated hardware or a general-purpose computer.
[0470] FIG. 56 is a block diagram showing a configuration example of hardware of a computer that executes the above described series of processing.
[0471] A CPU (Central Processing Unit) 151 , a ROM (Read Only Memory) 152 , a RAM (Random Access Memory) 153 are interconnected via a bus 154 .
[0472] An input/output interface 155 is further connected to the bus 154 . To the input/output interface 155 , an input unit 156 of a keyboard, a mouse, etc., and an output unit 157 of a display, a speaker, etc. are connected. Further, to the input/output interface 155 , a storage unit 158 of a hard disk, a nonvolatile memory, etc., a communication unit 159 of a network interface etc., a drive 160 that drives removable media 161 are connected.
[0473] In the computer having the above described configuration, for example, the CPU 151 loads the program stored in the storage unit 158 into the RAM 153 via the input/output interface 155 and the bus 154 and execute it, and thereby, the above described series of processing is performed.
[0474] For example, the program to be executed by the CPU 151 is recorded and provided in the removable media 161 or provided via a wired or wireless transmission medium such as a local area network, the Internet, or digital broadcasting, and installed into the storage unit 158 .
[0475] Note that the program to be executed by the computer may be a program of performing processing in time sequence in the order in which the processing has been explained in the specification, or a program of performing processing in parallel or at necessary times when a call is issued or the like.
[0476] The embodiments of the present disclosure are not limited to the above described embodiments and various changes may be made without departing the scope of the present disclosure.
[0477] The present disclosure contains subject matter related to that disclosed in Japanese Priority Patent Application JP 2010-142864 filed in the Japan Patent Office on Jun. 23, 2010, the entire contents of which is hereby incorporated by reference. | An information processing device includes: a processor determining whether a basic stream that can be reproduced singly and an extended stream used for reproduction with the basic stream forming a video stream of contents to be copied are interleaved with respect to each data in a predetermined unit and recorded in a first recording medium based on control information recorded in the first recording medium; and a recording controller, in the case of a determination that the basic and extended streams are interleaved with respect to each data in the predetermined unit and recorded, designating a first file among the first file that manages the basic stream and allowing copying of the basic stream to a second recording medium, and designating a second file that manages the extended stream and allowing copying of the extended stream to the second recording medium. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to improvements in voltage regulator circuits and more particularly to improvements in voltage regulator circuits of the type that maintain the system voltage in a vehicle, or the like, in which electrical loads may be applied to a vehicle alternator at various engine speeds.
2. Description of the Prior Art
Electrical systems of today's vehicles typically use an alternator to convert the mechanical energy transmitted into it via its rotating shaft into electrical energy. The amount of current delivered by an alternator to its load is determined by many factors, such as the rotational speed of the shaft, the voltage of the system, and the amount of current flowing in the field coil of the alternator.
On the other hand, the amount of mechanical energy taken in by the alternator is nearly a linear function of the electrical energy delivered by it to the load: if the load draws twice as much electrical power, the alternator will pull approximately twice as much mechanical power in through its shaft. For a given shaft speed, the different levels of mechanical power are exhibited by variations in torque seen at the mechanical shaft of the alternator.
The rotating part of an alternator spins a coil which is energized via slip rings and brushes. This rotating coil, the "rotor" or "field" coil, sets up a magnetic field which moves through stationary coils, the "stator" coils, whose output is then delivered to the load via rectifiers. The output of the alternator is controlled by a voltage regulator which senses the system voltage and varies the field coil current to set the system voltage to some predetermined value. If the electrical load presented by the vehicle increases, the voltage regulator increases the field coil current, which increases the output current from the stator coils of the alternator until the system voltage is restored to its proper value. When the field coil current is increased, the torque exerted by the alternator through its input shaft and pulley increases.
Rapid changes in the amount of energy pulled by the alternator from the engine through its belt drive can cause several problems. Two that may be noticeable by the operator of the vehicle are belt squeal when the torque is rapidly increased to very high levels and idle surge. The idle surge problem is caused by the fact that modern day engines are made to idle at very low speeds, generally under computer control, to minimize polluting emissions. An engine that is idling may be putting out a total of 2 or 3 horsepower in mechanical energy used to overcome friction within the engine itself and the transmission, drive the alternator, and operate other rotating components on the engine, such as the water pump, air pump, air conditioning compressor, and so forth. The alternator may draw anywhere from 0.1 to 2 horsepower, depending on the electrical load requirements at the time. A rapid increase in the electrical loads, such as a electrically driven cooling fan or lights turning on may cause the alternator to rob the engine of up to half its output. This could push the engine close to stalling, causing the engine control computer to kick up the throttle to prevent the stall. Often the system overshoots and the idle speed briefly surges up to a higher than normal level. This is an undesirable condition.
Due to power dissipation problems, most existing alternator voltage regulators drive the field coil with a pulse width modulated square wave. The frequency of the drive is high enough that the field coil current changes very little during one cycle of the drive. Varying the duty cycle (the ratio of on to off time) changes the average level of field coil current. However, controlling the rate of change of the field coil current will control the rate of change in the torque seen by the engine.
In the past, several systems have been proposed to address these problems. One system proposed by Kirk, et al. in U.S. Pat. No. 4,459,489 uses a constantly fixed rate of increase for the field coil drive. The Kirk, et al. circuit controls the rate of increase in the field drive to a constant maximum at all times. The reaction speed of the system is not determined by the size of the electrical load increase, or by the shaft speed of the alternator. Such systems could suffer from voltage stability problems, because they react slowly to load increases, causing the system voltage to dip to an unnecessary extent, even in response to only small load increases. Additionally, in many such systems, the reaction speed is constant for all engine speeds. When the engine is running faster, it develops a lot of horsepower and is relatively unaffected by the load changes from the alternator. Additionally, the higher rotational velocity means that the belt drive to the alternator experiences less available to transmit a given amount of mechanical energy to the alternator.
Another system that has been proposed by Bowman et al. in U.S. Pat. No. 4,636,706 uses predetermined update rates for the field coil drive. The Bowman et al. circuitry has a reaction time dependent on the shaft speed of the alternator with a piece-wise linear relationship. In this system, if the shaft speed is within a certain range, the rate of increase of the field drive duty cycle has a certain value. For a different shaft speed, the field drive increase will have a different value. At the transition between the two ranges, the field drive increase rate has a step change in value. Implementing this approach generally requires frequency discriminators for sensing the shaft speed. If the alternator is operated at one of the transitions, erratic operation can result.
SUMMARY OF THE INVENTION
In light of the above, it is, therefore, an object of the invention to control the rate of change of the torque of an vehicular alternator by changing the rate of change of the field coil current in a manner such that the rate of increase in field drive is linearly dependent on the stator frequency.
It is another object of the invention to provide a method and apparatus of the type described that is enabled by relatively simple electronic circuits.
It is yet another object of the invention to provide a method and apparatus of the type described which does not have transitions between the system reaction time as a function of alternator shaft speed, and is continuously variable in response time.
It is another object of the invention to provide a method and apparatus of the type described which provides a reaction speed that is related to the speed of the engine with which it is associated.
It is another object of the invention to provide circuitry for providing stator dependant torque control produced by an alternator of a vehicle.
It is still another object of the invention to provide a system that regulates a sensed voltage to within prescribed limits.
In accordance with a broad aspect of one embodiment of the invention, regulator circuitry is presented for connection to field coils of an alternator in an electrical system having a system voltage maintained by the alternator. The regulator circuitry includes circuitry for providing a variable drive to the field coils of the alternator, and circuitry for generating a velocity signal related to a rotational velocity of a stator. Circuitry is provided for producing a deviation signal when the system voltage deviates more than a predetermined amount from a predetermined value, and circuitry responsive to the deviation signal varies the field coil drive to the alternator at a rate dependent upon the velocity signal.
In accordance with a broad aspect of another embodiment of the invention, regulator circuitry is presented for connection to field coils of an alternator in an electrical system of a vehicle including an alternator and a system voltage maintained by the alternator. The regulator circuitry includes an analog to digital converter for connection to receive the system voltage and to deliver a digital output signal representing the system voltage, and a duty cycle generator for connection to the field coils produces an output signal proportional to a digital input signal. Register circuitry registers a value related to the digital output signal of the analog to digital converter and has an output connected to provide the registered value for the digital input signal to the duty cycle generator. System voltage sense circuitry provides an output signal when the system voltage falls below a predetermined value, and circuitry is provided for generating pulses at a frequency related to a rotational velocity of the alternator Control circuitry responsive to the output signal of the system voltage sense circuitry controls the duty cycle generator to produce an output related to the digital output signal of the analog to digital converter when the system voltage is above the predetermined level, and to increment the digital output signal of the analog to digital converter registered in the register circuitry when the system voltage falls below the predetermined value to produce an output that increases at a rate related to the rotational velocity of the alternator.
In accordance with a broad aspect of still another embodiment of the invention, regulator circuitry is provided for connection to field coils of an alternator in an electrical system of a vehicle including an alternator and a system voltage maintained by the alternator. In this embodiment, a clock circuit generates a clock signal, a free running counter outputs a count of the clock signals, and outputs a signal when the count is a predetermined value. Circuitry also is provided for outputting pulses at a frequency related to a rotational velocity of the alternator. A comparator circuit produces a deviation signal when the system voltage deviates from a nominal voltage by more than a predetermined amount, and a register is provided that contains a digital output value that can be incremented or decremented. A comparator circuit compares the count of the clock signals from the free running counter with the digital output value of the register circuit for producing a comparison signal, and a latch circuit is set by the signal of the free running counter when the count is the predetermined value and is reset by the comparison signal. Control circuitry responsive to the deviation signal of the comparator circuitry increments or decrements the register at a rate determined by the clock signal when the system voltage deviates from the nominal voltage by less than the predetermined amount, and increments or decrements the register at a rate determined by the digital output signal of the analog to digital converter when the system voltage deviates from the nominal voltage by more than the predetermined amount.
In accordance with another broad aspect of the invention, a method is presented for regulating the voltage delivered by an alternator in an electrical system having a system voltage maintained by the alternator. The method includes the steps of determining when the system voltage deviates from a nominal value more than a predefined amount; and when the system voltage deviation occurs, varying a pulse width modulation signal to drive the field coils of the alternator at a rate that is related to a rotational velocity of a stator of the alternator.
BRIEF DESCRIPTION OF THE DRAWING
The invention is illustrated in the accompanying drawing in which:
FIG. 1 is a box diagram showing an electrical circuit in accordance with a preferred embodiment of the invention for providing drive signals to the field coil of an alternator for use on an automobile or other vehicle.
FIG. 2 is a graph showing the relationship between system voltage and field drive duty cycle of a circuit constructed in accordance with the diagram of FIG. 1.
FIG. 3a is a graph of system voltage verses time showing a typical waveform produced by circuitry constructed in accordance with the diagram of FIG. 1 of the system voltage in response to a sudden load applied across the alternator of a vehicle or the like.
FIG. 3b is a graph of field drive duty cycle verses time of a system in accordance with the invention in response to the voltage represented by the waveform of FIG. 3a.
FIG. 4a is a graph of system voltage verses time showing a waveform of the system voltage when a load is applied to the alternator of a vehicle or the like, produced by regulator circuitry of typical prior art circuits.
FIG. 4b is a graph of field drive duty cycle verses time, in response to an increased load applied to the alternator, to produce the waveform shown in FIG. 4a.
FIG. 5a is a graph of system voltage verses time showing a system voltage response at low engine speeds to a load applied to the system produced by circuitry constructed in accordance with the diagram of FIG. 1.
FIG. 5b is a graph of field drive duty cycle which results from the circuit in accordance with a preferred embodiment of the invention, at low engine speeds to produce the system voltage response shown in the graph of FIG. 5a.
FIG. 6a is a graph of a waveform of the system voltage which results when a load is applied to the alternator at high engine speed produced by circuitry constructed in accordance with the diagram of FIG. 1.
FIG. 6b is a graph of field drive duty cycle verses time illustrating a waveform which results using a circuit in accordance with a preferred embodiment of the invention to produce the system voltage waveform of FIG. 6a.
FIG. 7 is a block diagram of an electrical circuit for providing an alternator regulator function in accordance with another preferred embodiment of the invention.
And FIG. 8 is an electrical schematic diagram of one control logic circuit embodiment which may be used in the voltage regulator shown in FIG. 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A block diagram of a circuit 10, in accordance with a preferred embodiment of the invention, for providing power signals for connection to field coil windings of an alternator of a vehicle (not shown) is illustrated in FIG. 1. The circuitry 10 includes an analog to digital converter and filter 11 that receives at its input the system voltage applied upon node 12. The purpose of the analog to digital converter and filter 11 is to sense the system voltage and provide a digital word which informs successive circuitry of the voltage of the system. The analog to digital converter and filter circuit 11 therefore provides a digital output on the line 13 that is related to the level of the system voltage on the node 12. The digital signal on the line 13 is applied to the "JAM" inputs of a duty cycle register circuit 14, in which they are registered.
The duty cycle register 14 contains the digital word which represents the field drive duty cycle calculated by the system. Inputs to the duty cycle register 14 include "JAM" inputs (presetting data inputs) from the analog to digital converter, a "JAM" enable from the control logic circuitry 22, and an "increase" input from the control logic circuitry 22.
In addition, the digital signal appearing on line 13 from the output of the analog digital converter and filter 11 is applied to an input of an undervoltage sense circuit 15. The output on the line 16 from the undervoltage sense circuit 15 is applied to an input of control logic circuitry 22. The undervoltage sense circuit 15 has a predetermined threshold so that when the value of the input on the line 13 falls below a predetermined value, an output on the line 16 is produced. Thus, the undervoltage sense circuitry 15 monitors the output from the analog to digital converter 11 to inform the control logic circuitry 22 when the system voltage drops below some predetermined threshold voltage. This voltage is the value at which torque control is enabled, as described below.
A signal from the stator of the alternator representing the stator phase may be applied to a node 20 which is connected to an input of a divider circuit 21. The output from the divider circuit 21 is connected to the control logic circuitry 22 by the line 23. The divider circuitry 21 is a simple digital divider, which divides the frequency seen on the stator phase sense input node 20 to feed the "increase" input of the control logic circuitry 22, and in turn the "increase" input of the duty cycle register 14.
The stator phase sense voltage may be derived, for example, from one of the stator coils at a point that may be connected to the connection between the diodes of a diode array of the type generally employed in conjunction with most alternator systems. Such sampling node is typically existing in most alternator systems, for example to signal "no rotation" of the rotor, to indicate a broken drive belt, or other such problem. Thus, the signal on the line 23 represents the rotational velocity of the alternator divided by the divisor established in the divider circuit 21, and by the relationship between the frequency seen at the sampling node and the rotational frequency of the alternator shaft. This relationship is fixed by the physical construction of the alternator.
The control logic circuitry 22 operates to produce a normal output on a line 24 that is connected to the "JAM" enable input of the duty cycle register 14. On the other hand, when a signal appears on the node 12 indicating an undervoltage condition of the system voltage, the signal on the line 23 representing the frequency or rotational velocity of the stator of the alternator is applied via the line 25 to the "increase" input terminal of the duty cycle register circuitry 14, and, concurrently, the signal on the line 24 to the "JAM" enable input is removed.
The duty cycle register circuitry 14 has the digital signal on line 13 from the output of the analog to digital converter and filter circuitry 11 registered therewithin, and, in the presence of the "JAM" enable signal provided on line 24, presents the registered signal on the output line 29, representing a "duty cycle word". The duty cycle generator 32 takes the duty cycle word from the output of the duty cycle register 14 and converts it into the field coil drive waveform. The field drive duty cycle may range from 0% to 100%, depending on the value of the duty cycle word. Thus, the duty cycle word on line 29 is connected to an input of a duty cycle generator circuit 32 which provides on its output line 33 connected to an output node 34 a signal related to the value of the duty cycle word on the line 29.
On the other hand, in the presence of a signal on the increase line 25, the signal on the "JAM" enable line 24 is removed and the value that is registered in the duty cycle register 14 is incremented or increased at a rate determined by the signal on the line 23, which, as above described, is related to the rotational velocity of the alternator. The increasing value registered in the duty cycle register 14 is continuously applied to the output on the line 29, constituting the duty word applied to the input of the duty cycle generator circuit 32.
The invention herein proposed provides for the increase in the rate in the field drive, for instance, linearly dependent on the stator frequency. Through the use of the divider circuit 21, the stator frequency may be sensed to generate an "increase" clock signal, so that at high stator frequencies, the field drive can increase at a high rate and at low stator frequencies, the field drive can increase at a lower rate.
The normal operation of the circuit of FIG. 1 is shown in FIG. 2. Some advantages of this approach over prior circuits are that simpler circuits are required to implement the system, and that there are no transitions in the system operation. This system has a continuously varying response time to load increases, and no problems occur because the system does not bounce between two separate modes of operation, as in some prior approaches. The jagged transfer curve for the proposed system reflects the digital implementation of the circuit and is merely the quantization of the duty cycle as compared to the continuous analog curve.
If the system voltage is below prescribed limits, the field drive duty cycle is increased, increasing the output current from the alternator to the load. This will increase the system voltage until it returns to the normal range, typically between 14.4 V and 14.6 V, as seen in the FIG. 2, and an equilibrium point is reached. Thus, the proposed system emulates conventional systems by allowing the duty cycle register 14 to become transparent. That is, the data fed to the "JAM" Inputs of the duty cycle register 14 are merely fed directly to the duty cycle generator 32, which maps the appropriate duty cycle value as a function of the data word generated by the analog to digital converter 11. During this mode, the control logic circuitry 22 maintains this operation by asserting the "JAM" enable signal to the duty cycle register 14.
FIGS. 3a and 3b show the operation of the system when a rapid increase in electrical load is encountered. The rapid load change will be marked by a rapid decrease in system voltage, shown by curve 40, to a value below the threshold value 41 indicated by the dotted line. This event occurs at time A. While the system voltage remains below the threshold value 41, the undervoltage sense circuitry 15 flags the control logic circuitry 22. In this operation mode, the control logic circuitry 22 de-asserts the "JAM" enable signal to the duty cycle register 14 and begins feeding the "increase" clock signal to the "increase" input of the duty cycle register 14. Each tick of the "increase" input increases the duty cycle by one count towards 100%. In this way, the duty cycle word is increased at a rate determined by the frequency seen at the stator phase sense input node 20, which reflects the shaft speed of the alternator. Thus, the rate of increase in field drive duty cycle between times A and B is shaft speed dependent. After the system voltage has recovered above the threshold value, the system returns to normal operation as described above.
The operation of the system, in accordance with the above embodiment of the invention is to prior art operation illustrated in FIGS. 4a and 4b, which show the rapid response of a typical conventional system. The operation in accordance with the invention is illustrated in FIGS. 5a and 5b which show a slow system response at low engine speeds, employing the system of the invention; and FIGS. 6a and 6b which show a fast system response at high engine speeds. The torque drawn by the alternator from the engine is almost linearly dependent on the field drive duty cycle, assuming a constant engine speed. Thus, with this system, large changes in torque occur slowly when engine speed is low and the engine is subject to stalling, as previously described. When engine speed is high, the torque changes more rapidly, restoring normal system voltage as fast as conditions warrant. Note that all systems look the same before and after the transients, but their behavior during the transition is different.
With reference now to FIG. 7, another circuit embodiment 50 is provided for regulating the field coil drive of an associated alternator (not shown). The circuit 50 includes a 10 bit register 51 having increment and decrement inputs and an output which provides a digital word or other digital signal output. Signals to the increment and decrement inputs of the 10 bit register 51 are provided by a control logic circuit 52. The control logic circuit 52 receives inputs from three comparators 53, 54, and 55, each of which has an input connected to receive a signal related to the system voltage, labeled "A-LINE". The first comparator 54 receives on its other input terminal a nominal voltage (VNOM) which provides a dither operation of the circuit 50 during normal operation within acceptable limits. The second comparator 53, on the other hand, receives on its other input terminal a voltage equal to the nominal voltage plus 0.1 volts, and operates to decrement the value held in the register 51 at a rapid rate. The comparator circuit 53 alternatively may be used to initiate a shut off operation to temporarily disengage the alternator from the system voltage, for example, in the event of a large voltage surge or spike that might otherwise be damaging to components associated with the electrical system of the vehicle. Finally, the third comparator 55 receives on its other input terminal a voltage equal to the nominal voltage minus 0.1 volts.
A stator input may be connected to an input node 60 to provide a signal on the line 61 to a stator phase sense circuit 62. The stator phase sense 62 provides a signal on its output line 65 related to the rotational velocity of the stator of the alternator, and is connected to an input of the control logic circuitry 52. The last input of the control logic circuitry 52 is provided on a line 66 from a clock circuit 67, having a frequency of, for example, 120 khz.
The output from the clock circuit 67 is additionally applied to a clock input of a 10 bit free running counter circuit 70. The outputs from the 10 bit free running counter 70 are connected to one input of a digital magnitude comparator circuit 72 on a bus 73. In addition, the outputs from the 10 bit register 51 are connected to another set of inputs of the digital magnitude comparator circuit 72 on a bus 74. The digital magnitude comparator 72 operates to produce an output on a line 76 when a value of the digital signals on the bus of 73 and 74 are equal. The line 76 is connected to the reset terminal of a latch 80.
In addition, the 10 bit free running counter circuit 70 provides an output on a line 81 when its count is equal to zero, and the line 81 is connected to the set terminal of the latch 80. The Q output of the latch 80 is connected to the gate of a power FET 85 or a control element other power switching device that may be connected in the field coil drive circuit to control the field coils of the alternator.
FIG. 8 shows one logic circuit embodiment which may be used for the control logic circuitry 52 in FIG. 7. In the circuit, the input and output terminals are illustrated with the respective reference numerals of the lines and circuitry to which they connect in the block diagram shown in FIG. 7. The control logic circuitry 52 can be realized with discrete logic components, or may be constructed utilizing a partially or fully programmed microprocessor or logic gates in a custom integrated circuit.
As described above, the system "A-LINE", which may be the battery line voltage, is sensed by three comparators 53, 54, and 55. The middle comparator 54 compares the "A-LINE" voltage to a nominal value, VNOM. If the "A-LINE" voltage is below the nominal voltage, the control logic circuitry 52 will increment the duty cycle register 51 until the "A-LINE" voltage exceeds the nominal voltage. This causes the control logic circuitry 52 to decrement the 10 bit register 51 and the cycle repeats itself. During normal operation, the 10 bit duty cycle register 51 therefore toggles up and down by one count, but this only results in a change in the field coil drive duty cycle of 0.1%, which should be an acceptable amount of dither.
Thus, in the normal operation of the circuitry 50, when only the output of the comparator 54 is effective, the rate of change of the duty cycle is constant. On the other hand, the other two comparators 53 and 54 become effective to sense when the error voltage (the "A-LINE" voltage minus the nominal voltage) is larger than a predetermined value in either the positive or negative directions, for example 0.1 volt in the embodiment shown. When the error exceeds this predetermined value, the control logic circuitry 52 causes the contents of the duty cycle register to be changed more rapidly than otherwise. The slew rate of the duty cycle will thus adapt to the operating conditions.
The 10 bit free-running counter 70 is normally clocked by the 120 khz clock signal from the clock 67. Thus, the frequency of the control loop is set to about 120 hz, with the free running counter 70 going through bit combinations from all zeros to all ones. When the counter reaches a predetermined count, for example, all zeroes, the "=0000" signal sets the latch 80, which turns on the field coil drive transistor 85. Meanwhile, the digital magnitude comparator 72 monitors the contents of the free running counter 70 and the register 51. When the contents of the counter 70 and the register 51 are equal, the output from the magnitude comparator 72 resets the latch 80 and the field coil drive transistor 85 is turned off, thereby establishing the duty cycle of the circuit 50. Since the value registered in the register 51 establishes the duty cycle of the system, increasing its value increases the duty cycle.
The 10 bit duty cycle register 51 therefore makes the loop behave as if an integrator (pole at zero hz) were embedded in the loop. This means that no matter how large the initial voltage error, the system will eventually settle back to the exact same nominal voltage as long as the final duty cycle is within the normal operating limits.
The acceptable level of dither and loop stability criteria fix the required resolution for the duty cycle and also the possible update frequency for the contents of the register 51, so that the register 51 is not constantly overshooting and undershooting the correct resting value it obtains. This establishes a maximum on the allowable "slew rate" for the duty cycle.
Varying the rate of change of the duty cycle in this manner gives a stable loop, while minimizing the possible response time to large load changes. Load response control can be accomplished by allowing the frequency seen on the stator input node 60 to determine the update rate for the register 51. In this manner, the rotational speed of the alternator will adjust the response time of the regulator to load changes. At low speeds, the regulator would react slowly and at higher speeds, the circuit would settle quickly. Using the stator input in this manner varies the response time in a continuous fashion, eliminating any discontinuities caused by discrete mode changes initiated by a frequency discriminator monitoring the stator input.
Although the invention has been described and illustrated with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example, and that numerous changes in the combination and arrangement of parts can be resorted to by those skilled in the art without departing from the spirit and scope of the invention, as hereinafter claimed. | Regulator circuitry for connection to field coils of an alternator in an electrical system of a vehicle having a system voltage maintained by the alternator includes circuitry for providing a variable drive to the field coils of the alternator, and circuitry for generating a velocity signal related to a rotational velocity of a driven shaft of the alternator. The regulator circuitry also includes circuitry for producing a deviation signal when the system voltage deviates more than a predetermined amount from a predetermined value, and circuitry responsive to the deviation signal to vary the field coil drive to the alternator at a rate dependent upon the velocity signal. In addition a method is presented for regulating the voltage delivered by an alternator in an electrical system having a system voltage maintained by the alternator. The method includes the steps of determining when the system voltage deviates from a nominal value more than a predefined amount; and when the system voltage deviation occurs, varying a pulse width modulation signal to drive the field coils of the alternator at a rate that is related to a rotational velocity of a stator of the alternator. | 8 |
This Application is the U.S. National Phase Application of PCT International Application No PCT/GB03/004159 filed Sep. 22, 2003. The present invention relates to restraining apparatus, and especially but not exclusively to apparatus for securing children.
DESCRIPTION OF THE RELATED ART
It is often difficult to control a group of children and to keep them safe in the group, particularly when taking them for walks or excursions.
BRIEF SUMMARY OF THE INVENTION
According to the present invention there is provided restraining apparatus for coupling two or more users comprising at least one spine member with at least two lateral attachment members for coupling the users to the spine member, the spine member having two planes, and having more flexibility in one plane than in the other.
The spine member can be an elongate rod or plate from which the lateral attachment members extend sideways. The rod or plate is typically inextensible along its long axis and is preferably rigid in its vertical plane but preferably has some lateral resilience, so that it can bend sideways in its horizontal plane with the movement of the users. Lateral resilience in the horizontal plane in use of the device is preferable to lateral resilience in the vertical planes because rigidity in the vertical plane with respect to the user has the benefit that parts of the spine member have a reduced tendency to sag and become trampled underfoot. Therefore, preferred embodiments of the device can bend laterally from side to side in the horizontal plane of the device, but not up and down in the vertical plane of the device.
In some embodiments the spine member is axially compressible and/or extensible. Plastics material is suitable for the spine members. Optionally, at least a part of the spine member is made of corrugated plastic. Alternatively, the spine member is made of composite plastics material or rubber. The spine may have a stiffening member, such as a plastics, metal or composite plate covered with the plastics or rubber material, to enhance rigidity in one plane.
The spine being flexible and/or compressible allows the users to approach each other and to turn corners.
Preferably, the attachment members are securely attached, but in a releasable manner and are typically coupled to the spine member at nodes on the spine member. Preferably, each node has two attachment members.
The attachment members are typically arms. The arms may be laterally flexible and/or axially extensible and/or compressible, to absorb sudden forces. In some embodiments they can be rigid or semi-rigid, or preferably non-flexible in some planes but flexible in others.
Typically, the attachment members are pivotable with respect to the spine member. Optionally, each attachment member at each node is pivotable with respect to the other attachment member. In preferred embodiments, each node has a pair of attachment members extending laterally from opposite sides of the spine member. It is not necessary to have an attachment member extending from each side of each node; a single node can instead bear a single attachment member. Attachment members can all extend from the same side of the spine member, or from different sides. In one optional embodiment, members are staggered along the spine member.
Pivotal attachment members allow users of different heights to share one node.
Optionally, two or more spine members are connected together.
This allows a long chain of spine members and nodes to be built up, which is useful to connect a large number of users.
Preferably, the apparatus also includes harnesses to be worn by each user. Typically, each harness is adapted to releasably engage an attachment member, to attach the user to the spine member. Typically, the harness includes a belt. Optionally, the harness includes a shoulder strap, but simple waist belts would suffice. Preferably, each harness has at least one socket to engage a protrusion on an attachment member, but other attachment formations can be used instead. Optionally, the socket includes a first plate, biased apart from and pivotable relative to a second plate, and pivoting moves the ends of the plates at the socket mouth apart to enlarge the mouth to engage/release an attachment member. Typically, the plates are biased apart by a coil spring. Typically, both plates are pivotable with respect to the socket. Another alternative attachment system could involve moulded plastic ball-joints and sockets, clips, buckles, or other similar connectors that are commercially available.
In another aspect the invention provides a method of securing or restraining a person, comprising harnessing the person to a spine member via an attachment member, the spine member having at least two planes, and having a different degree of flexibility in respective planes.
Typically more than one person is harnessed to the spine member.
In some embodiments the spine and/or the harness can be coloured brightly, and/or can incorporate luminous, reflective and/or light emitting devices such as LEDs and strobes to attract attention.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the present invention will now be described by way of example only and with reference to the following drawings, in which:—
FIG. 1 is a plan view of six children using a restraining apparatus;
FIG. 2 is a plan view with the children with the apparatus in a compressed position;
FIG. 3 is a plan view of the children in a curved configuration;
FIG. 4 is a front view of a harness worn by each child;
FIG. 5 is a front view of the apparatus worn by two children of different heights;
FIG. 6 is a perspective view of one embodiment of the apparatus;
FIG. 7 is a perspective view of an alternative embodiment of the apparatus;
FIG. 8 is a perspective view of an alternative embodiment of the apparatus;
FIG. 9 is a perspective view with interior detail of part of the apparatus, showing an arm located in a socket;
FIG. 10 is a side view with interior detail of the arm and socket of FIG. 9 ;
FIG. 11 is an exploded view of a node, spine members and attachment means;
FIG. 12 is a perspective view of the apparatus of FIG. 11 with the node secured to the spine members;
FIG. 13 is an exploded view of a node of the apparatus, spine members and an alternative attachment means;
FIG. 14 is a perspective view of the apparatus of FIG. 13 with the node secured to the spine members; and
FIGS. 15 a - 15 d show schematic views of different embodiments of the apparatus.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows six children 12 secured together by restraining apparatus 10 . The apparatus 10 has two elongate spine members 14 , 16 . Each node 18 , 20 , 22 has two lateral arms 24 , 26 , 28 , 30 , and 32 , 34 .
The spine members 14 , 16 are optionally axially compressible and/or extensible and/or laterally flexible in the horizontal plane of the apparatus in use, to allow the apparatus to bend. This allows the children 12 to approach each other ( FIG. 2 ) and turn corners ( FIG. 3 ). However, the spine members 14 , 16 are normally inextensible, or at least only very slightly axially resilient, so that the distance between the children cannot increase to any great extent. Also, the spine members are typically comparatively more rigid in the vertical plane than in the horizontal plane, so that the spine does not sag between nodes.
Different sizes of apparatus 10 are envisaged, depending on the number of children to be secured. To make a larger version of apparatus 10 , additional spine members and nodes can simply be attached to the apparatus 10 .
FIG. 4 shows a harness 36 that is used to attach the children 12 to the apparatus 10 . The harness 36 has a shoulder strap 38 and a belt 40 . The belt 40 is fastened by a simple buckle 42 . The belt 40 also has two sockets 44 for engagement with an arm of the apparatus 10 . Sockets 44 can optionally slide on rails 46 provided in the belt, so that the child can turn sideways with respect to the spine 14 , 16 . The sockets 44 can typically be switched between a first configuration where they are fixed immovably to the rails 46 , and a second configuration in which they can slide relative to the rails 46 .
FIG. 5 shows two different-sized children 12 secured to node 22 by arms 32 , 34 . Each user 12 is wearing a harness 36 , and a socket 44 in each harness 36 is engaged with an arm 32 , 34 of the node 22 . The arms 32 , 34 are pivotable with respect to the node 22 , to allow the different-sized children 12 to be connected to the apparatus 10 without twisting the apparatus 10 .
The arms 32 , 34 can also be axially and laterally resilient so as to resist the transfer of forces between the children connected to the node 22 .
FIG. 6 shows an embodiment of apparatus 10 , having spine members 60 connected to each other by single pivot nodes 54 . The spine members typically comprise an elongate strip covered with a non-pvc rubber. The spine members 60 can typically comprise thin sheets of plastic, metal or composite material (such as GRP or carbon fibre), orientated so that in use the sheets lie in the vertical plane. This allows lateral but not vertical flexibility of the spine members.
In this embodiment, each node 54 comprises a ring 56 and a rod 58 , which passes through the centre of the ring 56 in a direction parallel to the axis of the spine members 60 . Each pair of arms 62 , 64 is typically formed as a single piece, having a central bore arranged parallel to the axis of the spine members 60 and shaped to accommodate the rod 58 , which passes through the bore. Each pair of arms 62 , 64 is pivotal around the rod 58 and is thus pivotable with respect to the spine members 60 , but the arms 62 , 64 are not pivotable with respect to each other. The ends of arms 62 , 64 have elongate tabs 65 to engage in the sockets of the harness. Spine members 60 optionally have reflectors 68 , which help the children 12 to be seen in the dark.
FIG. 7 shows an embodiment very similar to that of FIG. 6 , except that the rings 56 of each node 54 are closed or covered, typically by a rubber or plastics gaiter. This could help prevent fingers from becoming trapped in the nodes 54 . In this embodiment the arms 62 , 64 could be pivotable independently of one another.
FIG. 8 shows an alternative embodiment of apparatus 110 , having a number of spine members 160 , each of which includes a portion of corrugated plastic tubing. The corrugated tubing allows the spine members 160 to bend laterally and to be compressed and stretched axially. The other major difference from the previous embodiment is that the arms 162 , 164 are pivotable relative to each other, as well as relative to nodes 154 . The arms 162 , 164 are also typically resilient and can be formed from a rubber material. These arms could of course be used with the earlier embodiments.
FIGS. 9 and 10 show views of arm 62 engaged in socket 44 . Inside socket 44 is a grip device 90 , which includes two plates 92 , 94 , each having an aperture to receive opposite ends of elongate tab 65 on the end of the arm 62 . The plates 92 , 94 are pivotable about respective pivot points 96 , 98 and a coil spring 93 held in compression between the plates on one side of the pivot points 96 , 98 at the end furthest from the socket mouth urges the other ends of the plates together to capture the tab 65 in the apertures. Dual buttons 95 , 97 are connected to the plate ends above and below the spring 93 .
The dual buttons enable release from the apparatus.
Simpler connectors are possible, along the lines of buckles or clips conventionally used with backpacks and webbing straps, and any connector to secure the child to the arm can be used.
FIGS. 11 to 14 show details of possible connections between nodes 54 and spine members 60 . FIG. 11 is an exploded view showing spine members 60 , the ends of which terminate in rods that can slide into vertical slots 72 in nodes 54 and are secured therein by bolts 74 or pins. Bolts 74 fit through a first aperture 76 in one side of ring 56 , a corresponding aperture 70 in the end of each spine member 60 and through a second aperture 76 in ring 56 . FIG. 12 is a non-exploded view of FIG. 11 .
FIG. 13 shows an alternative connection between nodes 54 and spine members 60 . Ring 54 has two end lobes 80 , which each have a cylindrical lateral protrusion 82 in one side. The protrusions 82 are shaped to engage sockets 84 in the ends of spine members 60 . Securing caps 86 attach to the protrusions 82 once they are engaged in sockets 84 . The caps 86 are typically screwed to the protrusions by engaging interior screw threads of the cap 86 with exterior screw threads on the protrusion 82 , but other engagement means could also be used. FIG. 14 is a non-exploded view of FIG. 13 .
To secure a child to the restraining apparatus 10 , the child 12 puts on a harness 36 and fastens the belt buckle 42 . One of the sockets 44 of the harness 36 is then connected to an arm 24 of the apparatus 10 . This is done by simultaneously pushing socket buttons 95 , 97 . This compresses the spring 93 and pivots the plates 92 , 94 so the ends of the plates 92 , 94 at the socket opening move away from each other. This widens the socket entrance enough to allow the elongate tab 65 to be inserted. Once the tab 65 is aligned with the apertures in the plates 92 , 94 , the buttons 95 , 97 are released, which moves the plate ends over the tab 65 , leaving the ends of the tab 65 projecting through the apertures in the plates 92 , 94 . Thus, the elongate tab 65 is trapped in the socket 44 and the child 12 is secured to apparatus 10 . The procedure is repeated to secure all the children required to respective arms of the apparatus 10 .
To disengage a child 12 from the apparatus 10 , the socket buttons 95 , 97 , are simultaneously compressed and held down. This compresses spring 93 , and pivots the plates 92 , 94 to widen the socket opening as before. This releases the tab 65 from the apertures in the plates 92 , 94 and the arm 62 is then pulled out of the socket 44 . The buttons 95 , 97 are now released and the child takes off the harness 36 . This procedure is repeated to release all children 12 from the apparatus 10 .
Modifications and improvements can be incorporated without departing from the scope of the invention. For example, the position of the tabs and sockets could be reversed, i.e. each arm could have a socket and the harness could have a tab to engage the socket.
The arm and socket do not have to engage by apertures in plates engaging the arms; any way of attaching the arm to the socket would be adequate, e.g. the arm could screw into the socket.
The socket could be replaced by a lock mechanism, requiring a special tool to release the arm, so that a child secured to the apparatus could not release itself.
Two sets of apparatus could be used parallel to each other, with a central column of children attached to both apparatus. FIG. 15 shows a number of different schematic combinations of children 12 , spines 100 and arms 110 . Not all of the nodes need to be provided with arms at each side, nor do all the nodes or arms need to be occupied by children.
Embodiments of the invention could be created using a single spine instead of separate spine members (thereby removing the need for nodes) where the arms extend out through apertures in the spine. The harnesses could be permanently attached to the apparatus (instead of releasably attached by the arm and socket connection). | Restraining apparatus for coupling together two or more users such as children while walking as a group. The apparatus comprises a spine member with lateral attachment arms for coupling the users to the spine member. The spine member is laterally flexible to allow the spine to bend from side to side when corners are being negotiated in use, but has sufficient stiffness in the vertical plane to resist sagging between the users. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of U.S. application Ser. No. 13/279,929, filed Oct. 24, 2011, now U.S. Pat. No. 8,544,213, issued Oct. 1, 2013, which claims priority in U.S. Provisional Application No. 61/406,005, filed Oct. 22, 2010, and is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present disclosed technology relates generally to an apparatus for raising and aligning the structural towers of a collapsible performance stage, and more specifically to a rolling shuttle which receives the ends of the structural towers of a collapsible performance stage and facilitates positioning the towers in their upright positions supporting a roof over the stage.
[0004] 2. Description of the Related Art
[0005] Mobile performance stages are commonly used for temporary venues, performances, or rallies. Typical mobile performance stages must be assembled on site. Modern mobile stages may come in the form of a trailer, wherein the mobile stage is collapsible to a compact and mobile unit. The APEX 3224 Mobile Stage, manufactured by APEX Stages of Pittsburg, Kans., is an example of such a mobile stage.
[0006] Mobile stages generally include a stage deck and can include a stage roof. In order to support the stage roof, columns or towers are often used as structural elements. A mobile stage can be a large structure, and its components are manufactured from steel or other structural, heavy metals. In a typical stage setup situation it may take four laborers to raise the stage roof from the stage deck. In doing so, the laborers may have to drag the base of the stage towers across the stage deck, which may damage the deck or the tower itself. Because these stages are typically rented out for limited use, resiliency and long-term reliability are important features.
[0007] Mobile stages are often an economical alternative to erecting a permanent stage at a site. The typical reasons for electing to use a mobile stage include temporary use, cost, and reliability. Cutting the costs of using a mobile stage provides additional incentive for using a mobile stage. The simplest way to cut costs would be to reduce the number of persons required to setup and operate the stage. Costs are also saved when the owner of a mobile stage knows the stage will last. These cost savings can be passed on to customers, increasing the incentive to use one mobile stage over another.
[0008] What is needed is a system of erecting a mobile stage featuring minimal labor, minimal time, and minimal wear on the mobile components. Heretofore there has not been a mobile stage tower-erecting apparatus with the capabilities of the invention presented herein.
SUMMARY OF THE INVENTION
[0009] The preferred embodiment of the present invention includes a connection post, including a socket joint, connected to a shuttle cart on casters. The socket joint is capable of receiving a ball connection at the base of a structural tower. This connection allows a single operator to fully assemble a mobile performance stage with ease and with no damage to the stage deck. The tower shuttle allows the towers to be moved into position no matter the required direction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The drawings constitute a part of this specification and include exemplary embodiments of the disclosed subject matter illustrating various objects and features thereof, wherein like references are generally numbered alike in the several views.
[0011] FIG. 1 is an isometric view of a tower shuttle embodying an aspect of the present invention.
[0012] FIG. 2 is an elevation view thereof.
[0013] FIG. 3 is a top plan view thereof.
[0014] FIG. 4 is a sectional view thereof taken generally along line 4 - 4 in FIG. 3 and showing a ball-and-socket interconnection.
[0015] FIG. 5 is an exploded, isometric view thereof.
[0016] FIG. 6 is an isometric view of an initial step of erecting a mobile stage assembly comprising an aspect of the present invention.
[0017] FIG. 7 is an isometric view of an intermediate step of erecting the mobile stage assembly.
[0018] FIG. 8 is an isometric view of a final step of erecting the mobile stage assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
I. Introduction and Environment
[0019] As required, detailed aspects of the disclosed subject matter are disclosed herein; however, it is to be understood that the disclosed aspects are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art how to variously employ the present invention in virtually any appropriately detailed structure.
[0020] Certain terminology will be used in the following description for convenience in reference only and will not be limiting. For example, up, base, front, back, right and left refer to the invention as oriented in the view being referred to. The words “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the embodiment being described and designated parts thereof. Forwardly and rearwardly are generally in reference to the direction of travel, if appropriate. Said terminology will include the words specifically mentioned, derivatives thereof and words of similar meaning
[0021] A preferred embodiment of the present invention relies on the construction of a tower shuttle 17 using a connection post 1 mounted onto a shuttle cart 2 . The shuttle 17 is used in conjunction with a mobile stage 19 for erection and deconstruction of the stage.
II. Tower Shuttle 17
[0022] Referring to the drawings in more detail, reference numeral 17 generally refers to a tower shuttle. FIGS. 1-5 demonstrate the assembly of the tower shuttle 17 . The shuttle 17 is comprised of a connection post 1 and a shuttle cart 2 . The connection post 1 may be manufactured from a section of plastic pipe or plastic rod. Ideally, the material must hold a significant amount of weight and be nearly wear-resistant. The preferred embodiment comprises a connection post 1 formed from a plastic rod coated in ceramic, such as the Ceram-Back® line of products manufactured by Progressive Products Inc. of Pittsburg, Kans.
[0023] In the preferred embodiment, the shuttle cart 2 is a square plastic cart including four plastic casters 4 attached to the cart 2 with plastic caster brackets 6 . As shown in FIGS. 2 , 4 , and 5 , the casters 4 are located on a ball bearing wheel base 9 , which allows the casters 4 to freely rotate 360°, permitting the cart 2 to travel in any desired direction. The connection post 1 is attached to the cart 2 using a securing bolt 7 and washer 8 .
[0024] FIG. 3 demonstrates the tower shuttle 17 in further detail. The connection post 1 includes a base 5 which may be of a larger diameter than the main body of the post 1 . The base 5 physically contacts the shuttle 2 to disburse the force of a supported tower downward, and includes a chamfered bottom edge 11 . The connection post 1 further includes a chamfered top face 10 and houses a socket joint 3 at the apex of the post 1 . The socket joint 3 is adapted for receiving a ball joint connected to an appropriate tower.
[0025] FIG. 4 is a sectional view of the tower shuttle 17 showing how the socket joint 3 accepts the ball joint 20 of a stage tower 18 or other structural element. The connection forms a ball-and-socket joint that allows the tower 18 to raise no matter which direction the shuttle 17 is pushed.
[0026] FIG. 5 shows the complete assembly of the tower shuttle 17 in an exploded view. The bolt 7 threads through the washer 8 , the bolt-hole 12 located in the shuttle cart 2 , and into the connection post 1 . This forms a rigid connection between the post 1 and the cart 2 .
III. Mobile Stage 19
[0027] As shown in FIGS. 6-8 , in an embodiment of the present invention a mobile stage 19 is hauled to a performance site and is erected thereon. In the preferred embodiment, the mobile stage 19 will transform from a trailer hauled by a truck or other vehicle into a fully functional temporary performance stage.
[0028] The mobile stage 19 includes a roof section 13 , roof wing 14 , side walls 25 , a rear wall 26 , a stage deck 15 suspended upon a number of retractable stage jacks 27 , and at least two towers 18 . As shown in the progression demonstrated by FIGS. 6-8 , the roof wing 14 includes two attached towers 18 . As the towers 18 are moved from a starting, folded position in FIG. 6 to a final, standing position in FIG. 8 , the roof wing 14 fully extends over the stage deck 15 . This forms a complete stage with a roof covering for protecting performers and allowing lights and other equipment to be mounted above the performers.
[0029] The roof section 13 is also held suspended above the stage deck 15 via expanding pillars 23 . The pillars may expand using hydraulics, or other mechanical means; or they may expand as the towers 18 are moved into place. Once the roof section 13 is at an apex, and the towers 18 are in a final position, the expanding pillars 23 lock to maintain a final roof height.
[0030] Side walls 25 and a rear wall 26 are affixed to the roof section 13 . As the roof section 13 raises, the side walls 25 and rear wall 26 are also raised. These walls act to enclose the performance space of the mobile stage 19 .
[0031] Each tower 18 includes proximal and distal ends 22 , 24 . The proximal end is attached to the roof wing 14 via a hinged connection. The distal end 24 includes a ball joint 20 capable of being seated into the socket joint 3 of the tower shuttle 17 . Once the tower ball joint 20 is connected to the tower shuttle 17 , the shuttle aids in moving the tower 18 from a folded position as shown in FIG. 6 to a standing position as shown in FIG. 8 .
[0032] Upon the towers 18 and tower shuttles 17 reaching their final positions as indicated in FIG. 8 , the tower 18 is disconnected from the tower shuttle 17 , and the tower ball joint 20 is attached to a socket joint 16 affixed to the stage deck 15 . This secures the tower 18 in a final standing position that will ensure the stage 19 remains structurally supported during the duration of the performance.
[0033] Once the performance has been completed, the mobile stage 19 must be deconstructed and returned to its mobile form. The tower 18 is disconnected from the stage mounted socket joint 16 and reseated into the tower shuttle 17 . The shuttle 17 will guide the towers 18 from the standing position indicated in FIG. 8 back to a folded position indicated in FIG. 6 . The roof section 13 and stage deck 15 may then be folded up and the mobile stage 19 transported to a new location. A standard trailer hitch 28 is affixed to the mobile stage 19 at an end, and allows the stage to be hauled by a standard truck or transport tractor. A number of wheels, not shown, may be affixed to the mobile stage 19 to accommodate transportation of the stage.
[0034] Because the mobile stage 19 may include hydraulic power for moving the towers into place, the person operating the stage simply ensures that the tower ball joints 20 are firmly seated into the shuttle socket joints 3 , and then activates the stage's hydraulics. The towers will move into position, where the operator can then transfer the tower 18 from the shuttle socket 3 to the stage mounted socket 16 . This allows a single operator to setup and deconstruct the entire mobile stage 19 without additional labor.
[0035] It will be appreciated that tower shuttle 17 can be used for various other applications. For example, the transforming structural element does not need to be a mobile performance stage 19 . The structural element could be a store-front which transforms from a closed position to an open position by erecting towers to support said store front. Moreover, the tower shuttle 17 can be compiled of additional elements or alternative elements to those mentioned herein, while returning similar results.
[0036] It is to be understood that while certain aspects of the disclosed subject matter have been shown and described, the disclosed subject matter is not limited thereto and encompasses various other embodiments and aspects. | A transportable, transformable structure utilizing a tower shuttle apparatus for converting the structure from a closed, transportable unit to an open, stationary unit. The tower shuttle includes a connection post, including a socket joint, connected to a shuttle cart on casters. The socket joint is capable of receiving a ball connection at the base of a structural tower affixed to the transformable structure. This connection allows a single operator to fully assemble a mobile performance stage or other transportable, transformable structure with ease and with no damage to the stage deck. The tower shuttle allows the towers to be moved into position no matter the required direction. | 4 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of prior U.S. patent application Ser. No. 15/055,570, filed Feb. 27, 2016, which application is hereby incorporated by reference.
BACKGROUND
1. Technical Field
[0002] The subject matter described herein relates generally to herbal tea compositions, and in particular to herbal tea compositions which provide medicinal benefits when consumed.
2. Background Information
[0003] Babies often have digestive discomforts such as gas, constipation, acid reflux and colic which prevent them from sleeping for prolonged periods of time, and causes them to be irritable.
[0004] The present invention provides herbal tea compositions that, when consumed as a beverage by babies, eases common baby digestive discomforts and helps them sleep better and feel better.
SUMMARY OF THE INVENTION
[0005] Herbal tea compositions according to the invention involve blends of fennel seed and cumin seed. Some blends may also include dried chamomile flower.
[0006] One of the herbal tea composition blends is made up of about 55% (by weight) to about 65% (by weight) fennel seed, with the remaining amount being cumin seed. A variation of this blend disclosed is more specifically defined where cumin seed makes up about 35% (by weight) to about 45% (by weight) of the composition.
[0007] Another herbal tea composition blend disclosed containing dried chamomile flower is made up of about 5% (by weight) to about 15% (by weight) of the composition, with the remaining amount being made up of fennel seed and cumin seed. A variation of this blend is more specifically defined where fennel seed makes up from about 45% (by weight) to about 55% (by weight) of the composition, cumin seed makes up from about 35% (by weight) to about 45% (by weight) of the composition, and dried chamomile flower makes up from about 5% (by weight) to about 15% (by weight) of the composition.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0008] The disclosed subject matter now will be described more fully hereinafter with reference to the accompanying Examples, in which some, but not all embodiments of the disclosed subject matter are described. Detailed descriptions of preferred embodiments 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 invention in virtually any appropriately detailed system, structure or manner.
[0009] Herbal tea compositions according to the invention involve blends of fennel seed and cumin seed. In preferred embodiments, the compositions can be prepared to comprise between about forty percent (40%) by weight to about seventy percent (70%) by weight fennel seed, and about thirty percent by weight (30%) to about sixty percent (60%) by weight cumin seed. Organically grown fennel and cumin seeds may be used in herbal tea compositions of the invention to provide herbal tea compositions that may be organically certified. A particularly desirable composition of the blend is about sixty percent (60%) by weight fennel seed and about forty percent (40%) by weight cumin seed. This particular composition has shown to be commercially desirable in that it provides the sought-after benefits of easing baby digestive discomforts, improving babies' sleep and mood, while presenting an herbal tea blend which is accepted by babies.
[0010] Another preferred herbal tea composition according to the invention involves blends of cumin seed, fennel seed and dried chamomile flower. In preferred embodiments, the compositions can be prepared to comprise between about thirty percent (30%) by weight to about sixty percent (60%) by weight fennel seed, about thirty percent (30%) by weight to about sixty percent (60%) by weight cumin seed, and about five percent (5%) by weight to about fifteen percent (15%) by weight dried chamomile flower. Dried chamomile flower made from organically grown chamomile flowers may be used in herbal tea compositions of the invention to provide herbal tea compositions that may be organically certified. A particularly desirable composition of the blend is about fifty percent (50%) by weight fennel seed, about forty percent (40%) by weight cumin seed, and about ten percent (10%) by weight dried chamomile flower. This particular composition has shown to be commercially desirable in that it provides the sought-after benefits of easing baby digestive discomforts, while increasing improvement in babies' sleep, and presenting an herbal tea blend with increased acceptance by babies.
EXAMPLES
[0011] The following examples have been included to provide guidance to one of ordinary skill in the art for practicing representative embodiments of the disclosed subject matter.
Example 1
Representative Procedure for Preparing Herbal Tea Composition
(60% Cumin Seed/40% Fennel Seed Blend)
[0012] The procedure described is for a three hundred (300) gram batch that produces approximately two hundred (200) tea bags.
[0013] Initially, one hundred eighty (180) grams cumin seed and one hundred twenty (120) grams fennel seed are selected and washed thoroughly. After the ingredients have air-dried in a sterilized manner, they are mixed thoroughly until a uniform consistency is achieved. The blend is then packaged in tea bags at one point five (1.5) grams per bag.
Example 2
Representative Procedure for Preparing Herbal Tea Composition
(60% Fennel Seed/40% Cumin Seed Blend)
[0014] The procedure described is for a three hundred (3 00 ) gram batch that produces approximately two hundred (200) tea bags.
[0015] Initially, one hundred eighty (180) grams fennel seed and one hundred twenty (120) grams cumin seed are selected and washed thoroughly. After the ingredients have air-dried in a sterilized manner, they are mixed thoroughly until a uniform consistency is achieved. The blend is then packaged in tea bags at one point five (1.5) grams per bag.
Example 3
Representative Procedure for Preparing Herbal Tea Composition
(50% Fennel Seed/40% Cumin Seed/10% Dried Chamomile Flower Blend)
[0016] The procedure described is for a three hundred (300) gram batch that produces approximately two hundred (200) tea bags.
[0017] Initially, one hundred fifty (150) grams fennel seed, one hundred twenty (120) grams cumin seed, and thirty (30) grams dried chamomile flower are selected and washed thoroughly. After the ingredients have air-dried in a sterilized manner, they are mixed thoroughly until a uniform consistency is achieved. The blend is then packaged in tea bags at one point five (1.5) grams per bag.
[0018] While the invention has been described in connection with preferred embodiments, they are not intended to limit the scope of invention to the particular forms set forth, but on the contrary, they are 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. | Herbal tea compositions that, when consumed as a beverage by babies, eases common baby digestive discomforts and helps babies to sleep and feel better. The compositions comprise fennel seed, cumin seed. Some blends additionally contain dried chamomile flower. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of International
[0002] Application No. PCT/KR2012/001919 filed on Mar. 16, 2012, which claims priority to Korean Application No. 10-2011-0023992 filed on Mar. 17, 2011, which applications are incorporated herein by reference.
TECHNICAL FIELD
[0003] The present invention relates to a pol I promoter derived from Vero cells and a recombinant vector comprising the same.
BACKGROUND ART
[0004] Since human infection by avian influenza occurred in Hong Kong in 1997, outbreaks have been recently increasing in China and Southeast Asian countries such as Vietnam and Indonesia. Besides, at the time of co-infection with both human influenza and avian influenza, there has been high possibility of emergence of influenza virus variants which may infect people due to gene shift between the two influenza viruses (Chen et al., 2008). In recent years, it has been reported all over the world that the new H1N1 influenza virus derived from swine viruses infected and killed people, and the World Health Organization (WHO) also has warned of the outbreak of a new type of epidemic influenza virus and recommended each country to establish countermeasures against this possibility (WHO, 2009; Garten et al., 2009; Smith et al., 2009). There is still no effective preventive vaccine worldwide. Tamiflu, as the treatment that is currently in use, is in short supply and is produced at an enormous cost. Moreover, Tamiflu resistant viruses have been recently discovered, with the result that, when a new influenza pandemic arises, the technology for treating it is absent in the world.
[0005] In the present, reverse genetic pol I-pol II promoter systems used all around the world employ a human-derived promoter (Hoffmann et al., 2000). The thus developed human promoter systems are effectively operated in 293T cells, which are human-derived cell lines, to effectively create viruses, but the recombinant virus to be used for producing human vaccines cannot use cancer cells from human. Therefore, the Food and Drug Administration (FDA) in USA and the WHO have recommended Vero cells derived from African green monkeys (WHO, 2005). Although the human-derived pol I and pol II promoters operate the Vero cells derived from monkeys to some degree, the virus recovery rate is low as compared with for human-derived cells. Due to this low recovery rate, France tried to use chicken-derived pol I and pol II promoters to increase the virus recovery rate. Dr. Kawaoka's group in the USA succeeded in finding promoters derived from Madin-Darby
[0006] Canine Kidney (MDCK) cells, and thus obtained research results of increasing the virus recovery rate (Massin et al., 2005; Murakami et al., 2008).
[0007] Hence, the present inventors endeavored to provide a reverse genetic method of increasing the recombinant virus recovery rate by using the pol I promoter derived from Vero cells, and as the result, they found the pol I promoter derived from Vero cells and confirmed that the virus recovery rate can be increased by using the vector comprising the Vero pol I promoter, and then completed the present invention.
SUMMARY
[0008] Therefore, the present invention has been made in view of the above-mentioned problems, and an aspect of the present invention is to provide a pol I promoter derived from Vero cells and a recombinant vector comprising the same.
[0009] In accordance with an aspect of the present invention, there is provided a promoter having a nucleotide sequence as set forth in SEQ ID NO:1 or SEQ ID NO:2.
[0010] In accordance with another aspect of the present invention, there is provided a recombinant vector for producing viruses, the recombinant vector comprising the promoter having a nucleotide sequence as set forth in SEQ ID NO:1 or SEQ ID NO:2.
[0011] In accordance with another aspect of the present invention, there is provided a Vero cell transformed with the recombinant vector.
[0012] In accordance with another aspect of the present invention, there is provided a method for producing viruses by incubating Vero cells transformed with the recombinant vector comprising the promoter having a nucleotide sequence as set forth in SEQ ID NO:1 or SEQ ID NO:2.
[0013] The promoter may be a pol I promoter derived from Vero cells.
[0014] The recombinant vector may further include one or more genes selected from the group consisting of PB2, PB1, PA, HA, NP, NA, M, and NS.
[0015] In the present invention, it was confirmed that, as pol I promoter regions derived from Vero cells, there are a promoter (SEQ ID NO: 1) having 326 nucleotides and a promoter (SEQ ID NO: 2) having 212 nucleotides, upstream from the transcription initiation site (+1).
[0016] In the present invention, the v2pHW recombinant vector was constructed by PCR-amplifying a region corresponding to the obtained pol I promoter derived from Vero cells, removing the human pol I promoter from the existing pHW2000 vector (empty vector of the existing reverse genetic system), and then substituting the pol I promoter-guessable region derived from Vero cells therefor. Then, eight genes of the PR/8/34 virus was inserted into the recombinant vector, and it was confirmed whether or not the pol I promoter derived from Vero cells is effectively operated.
[0017] In the present invention, in order to check the protein expression efficiency of the recombinant vector comprising the pol I promoter derived from Vero cells, the existing pHW72-GFP vector developed by Hoffmann was modified to manufacture the v2pHW-GFP/luciferase vector prior to measurement.
[0018] As set forth above, when the pol I promoter derived from Vero cells according to the present invention is used, the viruses can be efficiently produced, thereby quickly producing pandemic vaccines as well as seasonal influenza vaccines, and thus, the present invention is useful.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 simply illustrates ribosomal RNA transcription regions repeated in a mammal, and specifically, FIG. 1A is a diagram showing a promoter region prior to the 18S gene of each repeat unit, and FIG. 1B is a comparative diagram of −8th to +11th nucleotide based on the transcription initiation site (+1) among Vero cells, human cells, and others;
[0020] FIG. 2 compares the nucleotide sequence among the Vero pol I promoter (326), and Macaca mulatta pol I promoter (NW — 001149581.1) and human pol I promoter, which are registered in GenBank;
[0021] FIG. 3A is a diagram illustrating that the v2pHW72-luci/GFP vector is established by substituting the human pol I promoter with the Vero pol I promoter in the existing pHW72-luci/GFP vector; and FIG. 3B is a diagram illustrating that PB2, PB1,PA, and NP genes of the PR/8/34 virus are cloned into the pcDNA3.1 myc-His(+) vectors and then the v2pHW72-luci/GFP vector is used to measure luciferase and GFP activities by the promoter in the 293T cells and the Vero cells;
[0022] FIG. 4 compares luciferase activities for the human pol I promoter and the Vero pol 1 promoter, which were measured in the 293T cells and Vero cells;
[0023] FIG. 5 compares GFP activities for the human pol I promoter and the Vero pol 1 promoter, which were measured in the 293T cells and Vero cells; and
[0024] FIG. 6 shows virus production efficiency between the existing human pol I promoter system and the Vero pol I promoter system in the MDCK cells by the time-specific virus titer TCID50/ml post transfection.
DETAILED DESCRIPTION
[0025] Hereinafter, the present invention will be described in detail with reference to the following examples. However, the following examples are merely for illustrating the present invention and are not intended to limit the scope of the present invention.
EXAMPLE 1
Searching of Promoter Gene Derived from Vero cells
[0026] Vero cells were treated with RNase to extract purely separated genomic DNA, and then various primers were prepared based on the nucleotide sequence of the 18S gene derived from human cells. Then, various combinations of PCR thereof were conducted and similar sizes of PCR products were purified, which were then cloned into the TA vectors (Promega), and then clones showing an insert having the same size as the PCR product were subjected to gene analysis.
[0027] In the present invention, the Vero pol I promoter region was expected by comparing the nucleotide sequence between the analyzed genes and human pol I promoter (GenBank accession no. U13369.1), or comparing the nucleotide sequences of the analyzed genes with the non-human primate Macaca mulatta whole genome shotgun sequence (GenBank accession no. NW — 001149581.1) and the Macaca mulatta chromosome 20 genomic scaffold, whole genome shotgun sequence (GenBank accession no. NW 001111333.1) obtained through the blast search in GenBank. As a result of analyzing the Vero pol I promoter region based on this, 326 nucleotides in total upstream from the transcription initiation site was confirmed, as shown in FIG. 2 . This showed to have about 91.1% homology to the human pol I promoter, and about 93% homology to the Macaca mulatta pol I promoter (NW — 001149581.1), which is somewhat higher than that of the human pol I promoter.
EXAMPLE 2
Construction of Vero Pol I Promoter Vector System
[0028] The human pol I promoter region was removed by using Kpnl, which is a restriction enzyme region in the pHW2000 vector (St. Jude Children's Research Hospital), and newly prepared BamHI, and then the Vero pol I promoter-guessable region, of which the gene nucleotide sequence was confirmed through PCR amplification, was inserted thereinto, which is then called the vpHW vector.
[0029] Then, influenza virus universal primers proposed by Hoffmann were used to amplify eight genes (PB2, PB1, PA, HA, NP, NA, M, and NS) of the PR/8/34 virus, which is a backbone for producing influenza virus vaccines, by a reverse genetic method, and then the amplified genes were inserted into the newly modified vpHW vector. The inserted genes were analyzed to check whether or not the same virus genes were inserted.
[0030] The primers used are as follows.
[0000]
TABLE 1
Primer
Sequence
Bm HA-1F
TATTCGTCTCAGGGAGCAAAAGCAGGGG
(SEQ ID NO: 3)
Bm NS-1F
TATTCGTCTCAGGGAGCAAAAGCAGGGTG
(SEQ ID NO: 4)
Bm NS-
ATATCGTCTCGTATTAGTAGAAACAAGGGTGTTTT
890-R
(SEQ ID NO: 5)
Ba NA-1F
TATTGGTCTCAGGGAGCAAAAGCAGGAGT
(SEQ ID NO: 6)
Ba NA-
ATATGGTCTCGTATTAGTAGAAACAAGGAGTTTTTT
1413R
(SEQ ID NO: 7)
Bm M-1F
TATTCGTCTCAGGGAGCAAAAGCAGGTAG
(SEQ ID NO: 8)
Bm M-1027R
ATATCGTCTCGTATTAGTAGAAACAAGGTAGTTTTT
(SEQ ID NO: 9)
Bm NP-1F
TATTCGTCTCAGGGAGCAAAAGCAGGGTA
(SEQ ID NO: 10)
Bm NP-
ATATCGTCTCGTATTAGTAGAAACAAGGGTATTTTT
1565R
(SEQ ID NO: 11)
Bm PA-1F
TATTCGTCTCAGGGAGCGAAAGCAGGTAC
(SEQ ID NO: 12)
Bm PA-
ATATCGTCTCGTATTAGTAGAAACAAGGTACTT
2233R
(SEQ ID NO: 13)
Bm PB1-1F
TATTCGTCTCAGGGAGCGAAAGCAGGCA
(SEQ ID NO: 14)
Bm PB1-
ATATCGTCTCGTATTAGTAGAAACAAGGCATTT
2341R
(SEQ ID NO: 15)
Ba PB2-1F
TATTGGTCTCAGGGAGCGAAAGCAGGTC
(SEQ ID NO: 16)
Ba PB2-
ATATGGTCTCGTATTAGTAGAAACAAGGTCGTTT
2341R
(SEQ ID NO: 17)
EXAMPLE 3
Virus Production Efficiency Using Vero Pol I Promoter System
[0031] Eight genes, which are to be used in a PR/8/34 virus reverse genetic system containing the existing human pol I promoter and a PR/8/34 virus reverse genetic system containing the newly modified Vero pol I promoter, were identically prepared. After that, three sets of eight genes were prepared for each group having the same amount of Vero cells, followed by transfection under the same conditions, and then the amounts of viruses produced for 48, 72, and 96 hours were measured in MDCK (madin-darby canine kidney) cells by the 50% Tissue Culture Infective Dose (TCID50/ml). As the result, it was confirmed that the titer (TCID50/ml) of the PR/8/34 virus produced by the Vero pol I promoter developed by the present invention was about 3 to 4 fold higher than that of the existing system on 72 hours post transfection, which showed higher virus production efficiency ( FIG. 6 ).
EXAMPLE 4
Efficiency of Vero Pol I Promoter Through Measurements of Luciferase and GFP Activities
[0032] The efficiency of the promoter in the Vero cells and 293T cells can be determined by measuring luciferase and Green Fluorescent Protein (GFP) activities under the polymerases of the same virus. Therefore, PB2, PB1, PA, and NP genes of the PR/8/34 virus were cloned into the pcDNA3.1 myc-His(+) vectors, and then the Vero cells and the 293T cells were simultaneously transfected with the v2pHW72-Luciferase/GFP vector in which the four vectors and the Vero pol I promoter were inserted. After 24 to 36 hours, the trasnsfected cells were collected, followed by measurement of luciferase and GFP activities.
[0033] As the result, as shown in FIGS. 4 and 5 , the luciferase activity in the 293T cells did not show a large difference among 212 and 326 nucleotide-sized Vero pol I promoters (v2pHW72 — 212 and v2pHW72-326) and the human pol I promoter (pHW72), but the luciferase activity in the Vero cells exhibited 1.7 to 2 fold higher for the Vero pol I promoters than the human pol I promoter. These results confirmed that the use of the pol I promoter derived from the Vero cells can lead to higher virus production efficiency than the existing human pol I promoter. | The present invention relates to a pol I promoter derived from Vero cells and a recombinant vector containing the same. When the pol I promoter derived from Vero cells according to the present invention is utilized, viruses can be manufactured efficiently, and consequently, the manufacture of both seasonal influenza vaccine and pandemic vaccine can be prepared more quickly to usefully address either situation. | 2 |
RELATED APPLICATIONS
[0001] This application claims benefit of priority from U.S. Provisional Application No. 60/497,885, filed Aug. 26, 2003 and entitled MULTIPLE STAGE RECIRCULATING SINGLE FEED REFRIGERATION SYSTEM WITH AUTOMATIC PUMP DOWN, which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to refrigeration systems, and more specifically, a refrigeration system having a single feed that incorporates a liquid transfer vessel that alleviates vessels in the system from flooding, provides easy displacement of liquid refrigerant from the flooded vessels and economizes liquid refrigerant lines and reduces the total system power (BHP) requirement.
BACKGROUND
[0003] One of the common events during the start up of a refrigeration facility is the failure of control valves. These failures are usually associated with the amount of dirt collected during construction and before the first operation of the control valves. The end result is the flooding of the recirculator's vessels. When a recirculator vessel is flooded a series of events are initiated, that are potentially dangerous to the plant safety and performance, such as compressor failure due to a liquid “slug,” relief of liquid refrigerant through relief lines vented to the atmosphere, overpressurizing of flanged and sealed lines; and excessive amount of time to return to operational conditions since the liquid refrigerant has to be evaporated and compressed to return to the high side of the system.
[0004] It is a therefore a desire to provide a recirculating system with single feed that decreases flash vapor at closer lower temperature recirculators, incorporates a liquid transfer vessel that helps prevent the vessels in the system from flooding, provides easy displacement of liquid refrigerant from the flooded vessels while economizing refrigerant liquid lines with insulation, pumps, and valves in the refrigeration system.
SUMMARY OF THE INVENTION
[0005] The efficiency (BHP/TR) in a refrigeration system is gained by reducing the amount of Brake Horsepower (BHP) required to produce a Ton of Refrigeration (TR). Efficiency is gained by supplying liquid refrigerant to the evaporators while minimizing the amount of flash vapor due to the throttling of saturated liquid refrigerant feeding the evaporator at its level of pressure/temperature. At lower temperature/pressure stages in a typical refrigeration system the difference in pressure and respective temperature is minimal, in the order of 2 psig to 5 psig, between stages. Therefore it is typical that the refrigerant liquid feed for the lower temperature/pressure stages would come from a higher pressure/temperature level, increasing the amount of flash vapor while decreasing the efficiency (BHP/TR). The single liquid refrigerant feed for the lower temperature/pressure level(s) is made directly to the evaporators at the lower temperature/pressure stage through the refrigerant centrifugal pump(s). That allows lowering the amount of flash vapor and increasing the energy efficiency by lowering BHP/TR.
[0006] The initial cost of an industrial refrigeration system is substantial, especially when several levels of temperature have to be maintained in a building. Common temperature levels are 55 degrees, 34 degrees, −10 degrees, −20 degrees and −40 degrees Fahrenheit. It is common to combine the different temperature/pressure on a single temperature/pressure stage to save initial costs on equipment installed. However, by doing so the energy requirements increase on the system. The present invention increases the efficiency of the system and at the same time decreases the amount of liquid lines, refrigerant pumps, and valves with less BHP consumed per TR There are additional savings in operational costs associated with maintenance required on fewer moving parts in the system.
[0007] Accordingly, a multiple stage recirculating single feed refrigeration system with automatic pump down and method are provided. A multiple stage recirculated single feed refrigeration system of the present invention includes a first high stage compressor for compressing vapor refrigerant from a first evaporator via a first recirculator; a condenser for receiving hot vapor refrigerant from the first compressor and condensing the hot vapor refrigerant to a liquid refrigerant; a high pressure receiver for feeding high pressure liquid refrigerant to the first recirculator; a second compressor for compressing vapor refrigerant from a second evaporator via a second recirculator and wherein the second recirculator is fed by liquid refrigerant from the first recirculator and the second evaporator is fed by the second recirculator; a third compressor for compressing vapor refrigerant from a third evaporator via a separator vessel wherein the third evaporator is fed by the second recirculator wherein excess liquid refrigerant is transferred to a separator vessel; a liquid transfer vessel for receiving excess liquid refrigerant from the separator vessel; a motorized valve in connection between the separator vessel and the liquid transfer vessel for controlling flow of the liquid refrigerant to the liquid transfer vessel; and a refrigerant liquid pump for transferring excess liquid refrigerant from the liquid transfer vessel to the second recirculator and for transferring liquid refrigerant to the high pressure receiver.
[0008] A multiple stage recirculated single feed refrigeration method of the present invention includes the steps of compressing a vapor refrigerant with a first compressor from a first evaporator via a first recirculator; condensing the hot vapor from the first compressor to a liquid refrigerant; feeding the liquid refrigerant from a high pressure receiver to the first recirculator; feeding the liquid refrigerant from the first recirculator to a second recirculator; feeding a second evaporator liquid refrigerant from the second recirculator; compressing vapor refrigerant from the second evaporator into the first receiver; feeding a third evaporator liquid refrigerant from the second recirculator; transferring overfed liquid refrigerant to the third evaporator to a separator vessel; compressing vapor refrigerant from the third evaporator into the first recirculator; flowing liquid refrigerant from the separator vessel to a liquid transfer vessel; pumping the excess liquid from the liquid transfer vessel to the second recirculator; closing flow of liquid refrigerant from the separator vessel to the liquid transfer vessel when the liquid refrigerant in the liquid transfer level attains a predetermined depth; closing an equalization line between the separator vessel and the liquid transfer vessel; opening an equalization line between the liquid transfer vessel and the high pressure receiver; pumping liquid refrigerant from the liquid transfer vessel to the high pressure receiver until the liquid refrigerant level in the liquid transfer vessel drops below the predetermined depth; closing the equalization line between the liquid transfer vessel and the high pressure receiver; opening the equalization line between the separator vessel and the liquid transfer vessel; opening flow of the liquid refrigerant from the separator vessel to the liquid transfer vessel; and pumping excess liquid refrigerant from the liquid transfer vessel to the second recirculator.
[0009] The foregoing has outlined the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The foregoing and other features and aspects of the present invention will be best understood with reference to the following detailed description of a specific embodiment of the invention, when read in conjunction with the accompanying drawings, wherein:
[0011] FIG. 1 is a schematic drawing of a prior art system; and
[0012] FIG. 2 is a schematic drawing of the present invention.
DETAILED DESCRIPTION
[0013] Refer now to the drawings wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views.
[0014] FIG. 1 is a schematic drawing of a typical prior art recirculated refrigeration system with multiple stages of temperature/pressure stages. The high stage compressor(s) 10 receive the vapor refrigerant from evaporator 7 separated from liquid refrigerant at recirculator 3 , compresses the vapor refrigerant and sends it to the evaporative condenser 1 where the vapor refrigerant changes phases and is transformed into liquid refrigerant at high pressure. The liquid refrigerant flows by gravity to the high pressure receiver 2 . From there the high pressure liquid refrigerant feeds recirculator 3 , through control valve 17 . After the established liquid refrigerant level is satisfied at recirculator 3 , liquid refrigerant passes through centrifugal or positive displacement pump(s) 3 p to evaporator(s) 7 . The liquid refrigerant feed line coming from pump 3 p at the recirculator 3 also has the capability of sending liquid refrigerant to recirculator 5 when the liquid refrigerant level at recirculator 3 is higher than desired. A control system is activated by level sensors installed at recirculator 3 and sends signal to solenoid control valve 15 installed between the pumps and evaporator to open or close as required to transfer liquid refrigerant from recirculator 3 to recirculator 5 . As shown in FIG. 1 , compressor 11 receives the vapor refrigerant from evaporator 8 separated from liquid refrigerant at recirculator 4 and compressor 12 receives the vapor refrigerant from evaporator 9 separated from liquid refrigerant at recirculator 5 .
[0015] Recirculator 4 is fed by refrigerant liquid refrigerant stored at recirculator 3 through control valve 18 . After the established liquid refrigerant level is satisfied at recirculator 4 the liquid refrigerant passes through pumps 4 p to evaporators 8 . The liquid refrigerant feed line coming from pump 4 p at the recirculator 4 also has the capability of sending liquid refrigerant to recirculator 5 when the liquid refrigerant level at the recirculator 4 is higher than desired. The control system is activated by level sensors installed between pumps and evaporator to open or close as required to transfer liquid refrigerant from recirculator 4 to recirculator 5 .
[0016] Recirculator 5 is fed by refrigerant liquid refrigerant stored at recirculator 5 through control valve 19 . After the established liquid refrigerant level is satisfied at recirculator 5 the liquid refrigerant passes through pumps 5 p to evaporators 9 . The recirculator 5 receives excess liquid refrigerant from recirculators 3 and 4 as described above. When the liquid refrigerant level at recirculator 5 is higher than desired, the refrigerant liquid refrigerant flows to liquid refrigerant transfer vessel 6 by gravity. Liquid transfer vessel 6 is equalized with recirculator 5 by control valve 13 so that the liquid transfer vessel 6 continues to fill up to a determined set level. At this set point of liquid refrigerant level control valve 13 closes the equalization line 22 to recirculator 5 and opens the equalization line to the high pressure receiver. After a time delay the refrigerant liquid pumps 6 p starts to send liquid refrigerant to the high pressure receiver 2 . After the level on the liquid transfer vessel 6 is lowered to a predetermined set point, control valve 13 closes the equalization to the high pressure receiver 2 and opens the equalization line to recirculator 5 . The cycle will be repeated as required depending of the liquid refrigerant level at recirculator 5 . Other valves such as check valves and shut off valves are used to keep the pressures separated at each level of the recirculators and are commonly used on this type of system.
[0017] FIG. 2 is a schematic drawing of the refrigeration system of the present invention designated generally by the numeral 50 . In the present invention evaporator 9 is fed by recirculator 4 pumps 4 p via a feed line 30 eliminating the need for pumps 5 p of the prior art systems. The liquid refrigerant feed control valve at recirculator 5 is eliminated. The amount of flash vapor at recirculator 5 is reduced since the evaporators 9 are fed by recirculator 4 instead of recirculator 3 which is at a higher temperature. The overfed liquid refrigerant to evaporators 9 is returned to separator vessel 5 and transferred by gravity to the liquid transfer vessel 6 . The refrigerant liquid pumps 6 p then send the excess liquid recirculated back to recirculator vessel 4 . This is achieved through bypass line 24 by a control valve 14 installed at the high pressure receiver liquid refrigerant return line 25 that stays closed due to the pressure differential. This feature improves BHP/TR efficiency for the multiple stage system and reduces the number of pumps installed.
[0018] Liquid transfer vessel 6 is connected through a motorized valve 26 to separator vessel 5 . Valve 26 is normally open. As soon as the liquid refrigerant level at the separator vessel reaches a level higher than desired, detected by a level sensor controlled by the computer control system, the motorized globe valve 26 closes, the control valve 13 closes the equalization line 22 to separator vessel 5 and opens the equalization line 28 to high pressure receiver 2 . After a time delay the refrigerant liquid pumps 6 p starts to send liquid refrigerant to the high pressure receiver 2 . After the level on the liquid transfer vessel 6 is lowered to a predetermined set point, control valve 13 closes the equalization line 28 to the high pressure receiver 2 , opens the equalization line 22 to recirculator 5 and opens motorized valve 26 . Other valves such as check valves and shut-off valves are used to keep the pressures separated at each level of the recirculators.
[0019] The sizing of the liquid transfer vessel is proportional to the amount of returning from the system during normal operation as well as the emergency high liquid refrigerant level on recirculators 3 and 4 . The line 32 for motorized valve 26 should be sized for very low pressure drop, preferably less than 0.1 psi/100 ft, and the motorized valve 26 should be full port ball valve and follow the line size dimension. The motorized ball valve should have the port vented upstream to avoid liquid refrigerant trapped within the valve. A butterfly motorized valve may be used.
[0020] The refrigerant liquid pumps of recirculator 4 have to be sized for the overfeed ratio and capacity required by evaporators 8 and 9 .
[0021] Liquid transfer vessel 6 preferably needs to be sized for two refrigerant liquid pumps including a standby pump. Refrigerant liquid pumps 6 p desirably are sized for a liquid refrigerant overfeed ratio smaller by one recirculation rate than the required overfeed ratio of evaporator 9 . The refrigerant liquid pumps 6 p desirably are sized for reduced pressure differential, 10 to 15 PSIG, since they have to return liquid only to recirculator vessel 4 , eliminating the need to serve a much higher liquid refrigerant pressure drop, typically 40 to 60 PSIG, requirement of evaporators 9 of the prior art systems.
[0022] The amount flash vapor at evaporator 9 has to be considered when sizing the liquid refrigerant feed header at evaporators 9 , normally 3 to 5 percent of vapor flash. The liquid refrigerant returned from liquid transfer vessel 6 by refrigerant liquid pumps 6 p , coming from a lower temperature/pressure helps to subcool the liquid refrigerant recirculated at recirculator vessel 4 decreasing the vapor flash during normal operation helping the refrigerant liquid pumps 4 p to avoid cavitation. Thereby increasing their useful life and decreasing vapor flash through the lines translates into more efficient liquid refrigerant distribution to evaporators 8 and 9 .
[0023] From the foregoing detailed description of specific embodiments of the invention, it should be apparent that a multiple stage recirculated single feed refrigeration system with automatic pump down that is novel and unobvious has been disclosed. Although specific embodiments of the invention have been disclosed herein in some detail, this has been done solely for the purposes of describing various features and aspects of the invention, and is not intended to be limiting with respect to the scope of the invention. It is contemplated that various substitutions, alterations, and/or modifications, including but not limited to those implementation variations which may have been suggested herein, may be made to the disclosed embodiments without departing from the spirit and scope of the invention as defined by the appended claims which follow. | A method and apparatus for a recirculating system with single feed that incorporates a liquid transfer vessel that helps prevent the vessels in the system from flooding, provides easy displacement of liquid refrigerant from the flooded vessels while economizing refrigerant liquid lines with insulation, pumps, and valves in the refrigeration system. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/715,726 entitled “Engine Off Vacuum Decay Method for Increasing Pass/Fail Threshold Using NVLD,” filed on Sep. 9, 2005, the contents of which are hereby incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
The present invention relates generally to the field of leak detection, and more particularly, to techniques and systems for detecting a leak in an automotive fuel system using Natural Vacuum Leak Detection (NVLD).
BACKGROUND OF THE INVENTION
Conventional fuel systems for vehicles with internal combustion engines can include a canister that accumulates fuel vapor from a headspace of a fuel tank. If there is a leak in the fuel tank, the canister, or any other component of the fuel system, fuel vapor could escape through the leak and be released into the atmosphere instead of being accumulated in the canister. Various government regulatory agencies, e.g., the U.S. Environmental Protection Agency and the Air Resources Board of the California Environmental Protection Agency, have promulgated standards related to limiting fuel vapor releases into the atmosphere. Thus, it is believed that there is a need to avoid releasing fuel vapors into the atmosphere, and to provide an apparatus and a method for performing a leak diagnostic, so as to comply with those standards.
One technique in use for detecting fuel system leaks is known as “Natural Vacuum Leak Detection” (NVLD). In that method, the fuel system, including the fuel tank and canister, are sealed from the atmosphere immediately after an engine shut-down. Over time, vacuum develops in a fuel tank due to gas law effects, especially due to cooling of the tank. A vacuum switch changes state at a certain vacuum level, and that change in state is detected by a processor. If a sufficient vacuum (a sufficiently low pressure) is reached in the system to trip or maintain the switch in the vacuum state, then the system is deemed pass the leak test.
In the present specification, unless otherwise indicated, the term “pressure” means absolute pressure, and a pressure is said to “decrease” down to absolute zero pressure, or a “perfect vacuum.” A pressure is said to be “below” a threshold pressure if the pressure, in absolute terms, has a value less than the threshold pressure. That is true whether the pressures are above or below atmospheric pressure. In contrast, as used herein, the term “vacuum” denotes a pressure below atmospheric pressure; a vacuum is said to “increase” as it approaches absolute zero pressure, and a vacuum is said to “decrease” as it approaches atmospheric pressure.
A disadvantage of a conventional natural or passive vacuum evaporative leak detection system is that the testing pass/fail threshold is too low. That is to say, the leakage required to fail an evaporative leak detection test is relatively small. It is desirable for a test to yield a fail status when leakage is just below the required limit set by the various government regulatory agencies. That would maximize the opportunity to locate, and then repair, a system leak. This is particularly difficult in compact and sub-compact automobiles, which typically have small fuel tanks and tightly packaged underbody components.
The fuel tank leakage detection capability for many evaporative leak monitors is 0.5 mm (0.020″) as designated by the Air Resources Board of California. Some evaporative leak monitor applications that utilize the NVLD product have unnecessarily low pass/fail thresholds. For example, a system leak of only 0.25 mm (0.010″) is often large enough to trigger a malfunction indicator light (M.I.L.) using standard natural vacuum methods. That test outcome is considered to be type “alpha” error. An alpha error is an error caused by a “good” system failing the test. A measurement of alpha error for a fuel system leak detection (often expressed as a percentage) is:
Alpha
Error
=
Number
of
Leaks
detected
when
Leak
<
0.5
mm
Number
of
Tests
with
8
°
C
.
/
2
hr
Condition
There is therefore presently a need to provide a method and system for decreasing the occurrence of alpha error by providing additional opportunities for the diagnostic to PASS even when medium system leakage exists. To the inventor's knowledge, no such technique is currently available.
SUMMARY OF THE INVENTION
One embodiment of the present invention is a method for determining whether a fuel supply system passes a leak test. The fuel supply system includes a fuel tank, an engine and a vacuum switch indicating whether a pressure level in the fuel tank is above or below a threshold pressure level. The method includes, before a shut-down of the engine, maintaining a pressure in the fuel tank below the threshold pressure level; detecting a shutdown of the engine; after detecting the shutdown, monitoring the vacuum switch; and determining that the system passes the leak test if a minimum predetermined time elapses before the vacuum switch indicates that the pressure in the fuel tank is above the threshold pressure level.
The method may further include the step of determining that the system passes the leak test if: (1) the vacuum switch indicates that the pressure in the fuel tank is above the threshold pressure level before the predetermined time elapses; and (2) after the vacuum switch indicates that the pressure in the fuel tank is above the threshold pressure level, the vacuum switch indicates that the pressure in the fuel tank is below the threshold pressure level.
The step of maintaining a pressure in the fuel tank below the threshold pressure level before a shut-down of the engine may further comprise providing a low-level purge flow. The low-level purge flow may be between about 1-2 standard liters per minute.
The step of determining that the system passes the leak test if a minimum predetermined time elapses before the vacuum switch indicates that the pressure in the fuel tank is above the threshold pressure level, may further include starting a timer upon engine shut-down.
The step of maintaining a pressure in the fuel tank below the threshold pressure level before a shut-down of the engine, may further comprise closing a valve to seal the fuel tank. The step of closing the valve may further include applying a damping coil current to prevent poppet resonance. The damping coil current may be about 30% of duty cycle at 500 Hz. The valve may be a Natural Vacuum Leak Detection (NVLD) valve. The predetermined minimum time may be about 200 seconds.
Another embodiment of the invention is a leak testing apparatus. The apparatus includes an internal combustion engine; a fuel tank connected for providing fuel to the engine; a fuel vapor pressure management processor; a vacuum switch connected to the processor, the vacuum switch indicating whether a pressure level in the fuel tank is above or below a threshold pressure level, a sensor connected to the processor for detecting a shut-down of the engine; and a storage device accessible to the processor. The storage device contains instructions that, when executed by the processor, cause the processor to maintain a pressure in the fuel tank below the threshold pressure level before a shut-down of the engine; after detecting the shut-down, monitor the vacuum switch; and determine that the system passes a leak test if a minimum predetermined time elapses before the vacuum switch indicates that the pressure in the fuel tank is above the threshold pressure level.
The storage device may further contain instructions that cause the processor to determine that the system passes the leak test if (1) the vacuum switch indicates that the pressure in the fuel tank is above the threshold pressure level before the predetermined time elapses; and (2) after the vacuum switch indicates that the pressure in the fuel tank is above the threshold pressure level, the vacuum switch indicates that the pressure in the fuel tank is below the threshold pressure level.
The storage device may further comprise a purge valve connecting a vacuum source to the fuel tank, wherein the processor may further contain instructions that cause the processor operate the purge valve to provide a low-level purge flow before engine shut-down is detected. The low-level purge flow may be between about 1-2 standard liters per minute.
The apparatus may further comprise a timer, wherein the storage device further contains instructions that cause the processor to start the timer upon engine shut-down.
The apparatus may further include a valve for sealing a vent of the fuel tank, wherein the storage device further contains instructions that cause the processor to close the valve to seal the fuel tank before engine shut-down in detected.
The storage device may further contain instructions that cause the processor to apply a damping coil current to prevent poppet resonance when closing the valve. The damping coil current may be about 30% of duty cycle at 500 Hz.
The valve may be a Natural Vacuum Leak Detection (NVLD) valve. The predetermined minimum time may be about 200 seconds.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of a fuel vapor system in accordance with the invention.
FIG. 2 is a flow chart illustrating a method for detecting leaks in a fuel system according to one embodiment of the invention.
FIG. 3 is a plot of pressure and temperature versus time showing test results of the method of the invention, for an experimental sample.
FIG. 4 is a plot of vacuum decay time versus tank level showing an effect of tank level on the method of the invention, for an experimental sample.
FIG. 5 is a plot showing percent beta error as a function of vacuum decay threshold, for an experimental sample.
FIG. 6 is a plot of the effect of damping current on the tank pressure.
DESCRIPTION OF THE INVENTION
Referring to FIG. 1 , a fuel system 10 for an engine (not shown), includes a fuel tank 12 , a vacuum source 14 such as an intake manifold of the engine, a purge valve 16 , a charcoal canister 18 , an electronic control unit or processor 76 with memory storage 77 , and a fuel vapor pressure management apparatus 20 .
The fuel vapor pressure management apparatus 20 performs a plurality of functions including signaling 22 that a first predetermined pressure (vacuum) level exists. The signaling 22 includes a vacuum switch that may be activated by movement of a diaphragm in response to a pressure differential across the diaphragm.
The fuel vapor pressure management apparatus 20 also performs “vacuum relief” or relieving negative pressure 24 at a value below the first predetermined pressure level, and “pressure blow-off” or relieving positive pressure 26 above a second pressure level.
Other functions are also possible. For example, the fuel vapor pressure management apparatus 20 can be used as a vacuum regulator, and in connection with the operation of the purge valve 16 and a logic process performed by the processor 76 , can perform large leak detection on the fuel system 10 . Such large leak detection could be used to evaluate situations such as when a refueling cap 12 a is not replaced on the fuel tank 12 .
It is understood that volatile liquid fuels, including gasoline, can evaporate under certain conditions, such as rising ambient temperature, thereby generating fuel vapor. In the course of cooling that is experienced by the fuel system 10 after the engine is turned off, a vacuum is naturally created by cooling the fuel vapor and air, such as in the headspace of the fuel tank 12 and in the charcoal canister 18 . In accordance with the NVLD test described above, the existence of a vacuum at the first predetermined pressure level indicates that the integrity of the fuel system 10 is satisfactory. Thus, signaling 22 is used to indicate the integrity of the fuel system 10 by determining that there are no appreciable leaks. Subsequently, the vacuum relief 24 at a pressure level below the first predetermined pressure level can protect the fuel tank 12 by preventing structural distortion as a result of stress caused by vacuum in the fuel system 10 .
The pressure blow-off 26 allows air within the fuel system 10 to be released while fuel vapor is retained. For example, in the course of refueling the fuel tank 12 through filler cap 12 a, the pressure blow-off 26 allows air to exit the fuel tank 12 at a high rate of flow.
A method 200 in accordance with one embodiment of the invention is represented schematically by the flow chart of FIG. 2 . The engine-off vacuum decay test of the present invention utilizes the ability of the NVLD to act as a vacuum regulator. With that in mind, a relatively predictable vacuum characteristic can be achieved in the fuel tank immediately before the engine is shut down. From that state, the NVLD switch is used immediately after engine shutdown to measure how long the tank is able to hold vacuum once the engine is turned off.
In order to pre-condition the fuel tank for the vacuum decay test of the invention, the NVLD must be closed at idle and a minimum, constant, purge flow provided. Thus, referring to FIG. 2 , if the engine is at idle (decision 210 ), the NVLD valve is closed by de-energizing the valve and the appropriate coil current is re-applied to prevent poppet resonance (step 225 ). In one embodiment, a fixed damping current of about 30% of duty cycle is applied at about 500 Hz. Alternatively, a variable damping current may be used if required. If the engine is not at idle, normal purge is resumed (step 220 ).
When the NVLD valve is closed, purge flow is set to a constant, low level (step 230 ). Experiments have shown that very little flow is required to keep the tank in vacuum with the NVLD de-energized. Typical purge rates of 1-2 standard liters per minute (slpm) are adequate; 1 slpm is preferred. In a preferred embodiment, the test is aborted if purge flow is too high.
In one embodiment of the invention, a fixed duty cycle purge is used, and purge at idle must exceed a minimum time before engine shutdown, or the test is aborted. In a more preferred embodiment, a fixed mass flow purge at idle is used, compensating for MAP, voltage, etc. Purging at idle is required to exceed either a minimum volume or a minimum time before engine shutdown. That purge time requirement may be adjusted to compensate for current tank volume. In a most preferred embodiment, an algorithm controls purge mass flow and NVLD damping current to attempt to maintain a fixed tank vacuum at idle. For example, the target fixed vacuum may be 7.5-8.0 mbar.
In the embodiment shown in FIG. 2 , a minimum time must be allowed (decision 235 ) for the fuel tank to stabilize before the system is ready (step 240 ) to perform a decay test upon engine shutdown. The engine is monitored for the idle condition during that minimum time.
After the minimum time has elapsed and the system is ready for the vacuum decay test, the engine is monitored for shutdown (decision 245 ), while continuing to assure that the engine remains in an idle condition (decision 210 ). Once engine shutdown has been detected, a timer is started. In a preferred embodiment, a 50 millisecond full-field coil pulse is applied to the NVLD coil. The pulse “pushes” the poppet into the seal to reduce or eliminate seal leaks.
From the point of engine shutdown, the switch is monitored by the system. In one embodiment, the NVLD switch input is sampled every ten seconds. In a more preferred embodiment, the switch status is input every second, or every 100 milliseconds. The system is monitored for one of three conditions.
First, the switch may remain closed (“no” in decision 250 ) for the duration of a minimum predetermined time period, also referred to herein as “vacuum decay threshold period” (decision 265 ). In one embodiment of the invention based on the testing of a specific test vehicle, that time period is 200 seconds. If the NVLD switch remains closed for the vacuum decay threshold period, that indicates a “no leak” condition, and that the fuel system has passed the vacuum decay test (step 270 ). That is considered the supplementary “PASS” condition; i.e., the engine off vacuum decay method is considered a supplementary method for achieving “PASS” results, and not the primary leak monitor. In a preferred embodiment, the NVLD is considered the primary leak detection method. Use of the two techniques together is discussed below with reference to FIGS. 3 & 5 .
Second, the engine may be restarted (decision 245 ) before the vacuum decay threshold period elapses. That is considered to be NO RESULT test. If the engine is restarted, the method returns to monitoring the engine for an idle condition (decision 210 )
Third, the switch may trip (decision 250 ) before the vacuum decay threshold period elapses (decision 265 ). That condition is also considered to be a NO RESULT test (step 255 ), but the method continues to monitor for a NVLD “PASS” condition (step 260 ), in which the switch closes due to gas law conditions in the tank. In one embodiment, the NVLD switch input is sampled every 60 seconds after the vacuum decay threshold period elapses to monitor for natural vacuum. The system also monitors for an environmental condition such as a change in temperature at the rate of 8° C. in 2 hours in order to validate the testing conditions.
The graph 300 of FIG. 3 shows tank pressure and system temperatures over time in three experiments run using the engine off vacuum decay test described herein in combination with the NVLD test. Each experiment was performed on a system having a 0.25 mm (0.010 inches) leak, a 60 liter tank holding 20 liters of fuel, and 3 slpm of background purge flow.
In a first experiment yielding pressure trace 305 , the system passed the NVLD test, but did not pass the vacuum decay test described above. Starting at a vacuum of 3 inches H 2 O, the tank pressure quickly rose to 1 inch H 2 O positive pressure. The NVLD switch was tripped during that pressure rise before the vacuum decay threshold period elapsed. That condition is considered to be a NO RESULT test (step 255 of FIG. 2 ), but the method continues to monitor for a NVLD “PASS” condition (step 260 ). Returning to the trace 305 of FIG. 3 , the pressure in the tank thereafter dropped back to 3 inches H 2 O vacuum, again changing the NVLD switch position during that pressure drop. That switch transition yielded a “PASS” result in the NVLD test. The pressure trace 305 illustrates that a system may “PASS” despite a too-rapid vacuum decay in the initial engine-off vacuum decay test.
Pressure trace 315 shows an experiment wherein natural vacuum began forming before the NVLD switch was opened; i.e., the tank pressure never rose sufficiently from the initial 3 inches H 2 O vacuum to trip the switch. That sequence yields a “PASS” condition in the vacuum decay test because NVLD switch did not open within the vacuum decay threshold period (decisions 250 , 265 of FIG. 2 ).
Pressure trace 325 illustrates a condition wherein the initial vacuum decay is sufficiently gradual to “PASS” the engine-off vacuum decay test of the invention, but insufficient natural vacuum is thereafter formed to trip the NVLD switch. Without the engine-off vacuum decay test of the present invention, that situation would have resulted in an “alpha” error, failing a system that should have passed.
Results of experimental runs of the engine-off vacuum decay test of the present invention are shown in FIGS. 4 & 5 . FIG. 4 is a scatter plot 400 showing vacuum decay times in seconds as a function of fuel tank level (percent full). The values are shown for leak sizes from 0.0 to 0.50 mm, as indicated in the legend. A 3 slpm background purge was used.
The time threshold has been held constant over all tank levels. The 200-second vacuum decay threshold period used in the experimental runs is shown as a bold horizontal line.
During the test period, it was noted that the decay time was somewhat inversely proportional to the tank volume. That was not expected, but is likely due to the strong ‘gas law’ phenomena in effect during the first few minutes after engine shutdown. For example, when the tank is nearly empty, one would expect the decay times to be much longer due to the larger vapor space. Decay time, however, remains relatively short. That behavior is most likely due to the strong transient positive temperature effects in the tank immediately after engine shutdown.
FIG. 5 shows a summary 500 of the effect of combining the engine off vacuum decay method of the present invention with the NVLD results. The plot shows error and pass rates as functions of the vacuum decay threshold. The trace 510 show beta error rates introduced at various vacuum decay threshold periods for a 0.50 mm leak, beta error being the passing of a leak that should have been detected. Note that if the vacuum decay threshold is set too low, a high degree of beta error is introduced. The vacuum decay threshold for the experimental runs represented by traces 520 , 530 , 540 (using leaks of 0.38 mm, 0.30 mm, and 0.25 mm, respectively) was set at 200 seconds to improve the PASS results with leak sizes less than 0.5 mm without incurring significant beta error at leak sizes of 0.5 mm and above.
As noted above, a low level current is applied to NVLD coil during idle purge in order to avoid poppet resonance caused by flow being pulled through the valve. That current provides a damping force to the valve poppet, but also reduces the effective force of the poppet return spring. In effect, the NVLD coil current can be used to modify the set-point of the NVLD vacuum regulating function. That function may be used to compensate for out-of-range purge flow during the pre-conditioning phase. FIG. 6 shows a plot 600 of pressure drop across the valve as a function of vacuum flow, for various voltage points.
To utilize the vacuum decay leak detection method of the present invention, the purge system must be able to operate with the NVLD valve de-energized at idle. The system should be capable of applying a damping current of approximately 30% duty cycle at 500 Hz) to the NVLD coil during idle to prevent poppet resonance. The damping current is not required if the filter hose is less than 20 cm long.
Several variable parameters of the system and method of the invention must be properly adjusted to avoid increasing beta error; i.e., passing fuel systems having a leak greater than 0.5 mm. Beta error may be about 3%-4% in preferred embodiments of the invention. In a most preferred embodiment, beta error is between 2% and 3%.
There is a risk of increasing beta error if the tank vacuum is too high at engine shutdown, or if the decay time threshold is set too low. Active, flexible control of those variables decreases beta error. Further, beta error may increase if a temperature drop is abnormally high directly after engine shutdown. It is preferred to abort the test if such conditions are found to exist.
As noted, an alpha error is the detection of a leak <0.5 mm where none exists. In preferred embodiments of the invention, alpha error of about 10%-15% is normal. In a most preferred embodiment, alpha error is between 5% and 10%.
Since the vacuum decay method is being used only to find additional PASS conditions, the method will not cause additional alpha error. Instead, the method and system of the invention reduce alpha error. If the vacuum decay threshold period is too high, the opportunity to lower the alpha error is reduced or lost. Further, if tank vacuum is too low directly after engine shutdown, the opportunity to lower the alpha error is similarly lost.
The foregoing detailed description is to be understood as being in every respect illustrative and exemplary, but not restrictive, and the scope of the invention disclosed herein is not to be determined from the description of the invention, but rather from the claims as interpreted according to the full breadth permitted by the patent laws. For example, while the method is disclosed herein with respect to use in combination with a natural vacuum leak detection technique, the system and method of the invention may be combined with other leak detection techniques in order to reduce alpha error. It is to be understood that the embodiments shown and described herein are only illustrative of the principles of the present invention and that various modifications may be implemented by those skilled in the art without departing from the scope and spirit of the invention. | A technique is provided for detecting leaks in a fuel system such as an automotive fuel system. The technique complements an on-board diagnostics evaporative leak monitor that uses natural vacuum leak detection (NVLD). The technique utilizes the same switch and valve utilized by NVLD.
Before engine shut-down, the system maintains a vacuum in the fuel tank and also provides a low-level purge flow. Upon engine shut-down, a timer is started and the NVLD switch is monitored to determine how long the vacuum is maintained in the tank. If the vacuum is maintained longer than a predetermined time period, then the system determines that the leak test is passed. If the vacuum decays faster than the predetermined time period, then the NVLD test is performed and system determines that the system passes the leak test if the NVLD test is passed. | 5 |
PRIORITY TO RELATED APPLICATION(S)
This application claims the benefit of European Patent Application No. 06116238.4, filed Jun. 28, 2006, which is hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
The invention relates to a novel process for the manufacture of the compounds of formula I:
wherein R 1 -R 5 are as defined in the detailed description and in the claims.
The pseudo proline dipeptides of formula I can be used as reversible protecting groups for Ser, Thr, and Cys and prove to be versatile tools for overcoming some intrinsic problems in the field of peptide chemistry [JACS 1996, 118, 9218-9227]. The presence of ΨPro within a peptide sequence results in the disruption of β-sheet structures considered as a source of intermolecular aggregation. The resulting increased salvation and coupling kinetics in peptide assembly such as Fmoc solid phase peptide synthesis facilitates chain elongation especially for peptides containing “difficult sequences”.
SUMMARY OF THE INVENTION
The present invention provides a short and technically feasible process for synthesizing the pseudo proline dipeptides of formula I:
wherein R 1 -R 5 are as defined in the detailed description and in the claims;
comprising the steps of: (a) reacting an amino acid derivative of formula II as defined herein with serine or threonine to obtain a dipeptide of formula III as defined herein; (b) adding the amine of formula V as defined herein to form the ammonium salt of the dipeptide of formula III in crystal form; (c) adding an acid to the ammonium salt in step (b) to release the free acid of the dipeptide of formula III from the ammonium salt, and removing the protonated amine from the reaction mixture; and (d) effecting the ring closure of the free acid of the dipeptide of formula III in step (c) with a certain compound as defined herein in the presence of an acidic catalyst to obtain the compounds of formula I.
This process provides a high yield of the product without any chromatographic purification step.
DETAILED DESCRIPTION OF THE INVENTION
In detail, the present invention provides a process for the manufacture of the compounds of formula I:
wherein: (1) R 1 is a side chain of an alpha amino acid, (2) R 2 is an amino protecting group, (3) R 3 and R 4 are independently either hydrogen or a C 1-4 -alkyl, and (4) R 5 is hydrogen or methyl;
wherein said process comprises the following steps:
(a) reacting an amino acid derivative of formula II:
wherein R 1 and R 2 are as defined previously,
with serine or threonine to obtain a dipeptide of formula III:
wherein R 1 , R 2 and R 5 are as defined previously;
(b) adding the amine of formula V:
wherein R 6 , R 7 and R 8 are independently selected from the group consisting of hydrogen, a C 1-4 -alkyl and a C 3-7 -cycloalkyl, with the proviso that not all of R 6 , R 7 and R 8 are hydrogen;
to form the ammonium salt of the dipeptide of formula III in crystal form:
wherein R 1 , R 2 , R 5 , R 6 , R 7 and R 8 are as defined previously;
(c) adding an acid to the ammonium salt in step (b) to release the free acid of the dipeptide of formula III from the ammonium salt, and removing the protonated amine from the reaction mixture; and
(d) effecting the ring closure of the free acid of the dipeptide of formula III in step (c) with a compound selected from the group consisting of:
wherein: (1) R 3 and R 4 are independently either hydrogen or a C 1-4 -alkyl, with the proviso that not both R 3 and R 4 are hydrogen, (2) R 9a and R 9b are independently a C 1-4 -alkyl, (3) R 10 is a C 1-4 -alkyl, a C 1-4 -alkanoyl or an aryl, and (4) R 11 is hydrogen or a C 1-3 -alkyl,
in the presence of an acidic catalyst to obtain the compounds of formula I.
It is further understood that the serine or threonine can be used either in its L- or D-configuration, as racemates, or in various mixtures of their isomers. Preferably the L-configuration is used.
The term “C 1-4 -alkyl” refers to a branched or straight-chain monovalent saturated aliphatic hydrocarbon radical of one to four carbon atoms. This term is further exemplified by radicals such as methyl, ethyl, n-propyl, isopropyl, n-butyl, s-butyl and t-butyl.
The term “C 3-7 -cycloalkyl” refers to a cycloalkyl group containing from 3 to 7 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl or cycloheptyl.
The term “aryl” relates to the phenyl or naphthyl group, preferably the phenyl group, which can optionally be mono-substituted or multiply-substituted by halogen, hydroxy, CN, CF 3 , NO 2 , NH 2 , N(H,alkyl), N(alkyl) 2 , carboxy, aminocarbonyl, alkyl, alkoxy, aryl and/or aryloxy. A preferred aryl group is phenyl.
The term “alkanoyl” relates to a C 1-4 -alkyl carbonyl group. Examples include acetyl, n-propanoyl, isopropanyl, n-butanoyl, s-butanoyl and t-butanoyl, preferably acetyl.
The term “side chain of an amino acid” used in connection with the R 1 substituent refers to side chains of the alpha amino acids selected from the group consisting of valine, leucine, isoleucine, methionine, phenylalanine, asparagine, glutamine, glutamic acid, histidine, lysine, arginine, aspartic acid, alanine, serine, threonine, tyrosine, tryptophan, cysteine, glycine, aminoisobutyric acid, and proline. For side chains of amino acids which carry a hydroxy group the hydroxy group is optionally protected by a hydroxy protecting group as defined below. For side chains that carry additional amino groups the amino group is optionally protected by an amino protecting group as defined below.
In certain preferred embodiments, R 1 is preferably a side chain of an amino acid selected from the group consisting of: valine, leucine, isoleucine, phenylalanine, asparagine, glutamine, glutamic acid, lysine, aspartic acid, alanine, serine, threonine, tyrosine, and tryptophan; more preferably serine and threonine.
The term “amino protecting group” refers to any substituents conventionally used to hinder the reactivity of the amino group. Suitable amino protecting groups are described in Green T., “Protective Groups in Organic Synthesis”, Chapter 7, John Wiley and Sons, Inc., 1991, 309-385. Suitable amino protecting groups are Fmoc, Cbz, Moz, Boc, Troc, Teoc and Voc. A preferred amino protecting group is Fmoc.
The term “hydroxy protecting group” refers to any substituents conventionally used to hinder the reactivity of the hydroxy group. Suitable hydroxy protecting groups are described in Green T., “Protective Groups in Organic Synthesis”, Chapter 1, John Wiley and Sons, Inc., 1991, 10-142. Suitable hydroxy protecting groups are t-butyl, benzyl, TBDMS and TBDPS. A preferred hydroxy protecting group is t-butyl.
The meaning of certain abbreviations as used herein is provided in the following table:
Fmoc 9-Fluorenylmethoxycarbonyl- Boc t-Butoxycarbonyl- Cbz Carbobenzyloxy Z Benzyloxycarbonyl tBU t-Butyl Moz p-Methoxybenzyloxycarbonyl Troc 2,2,2-Trichloroethoxycarbonyl Teoc 2-(Trimethylsilyl)ethoxycarbonyl Voc Vinyloxycarbonyl TBDMS t-Butyldimethylsilyl ether TBDPS t-Butyldiphenylsilyl ether HBTU O-Benzotriazole N,N,N′,N′-tetramethyl-uronium-hexafluoro- phosphate HOBt 1-Hydroxybenzotriazole HOSu N-Hydroxysuccinimide EDC (3-Dimethylamino-propyl)-ethyl-carbodiimide (hydrochloride) DIC N,N′-Diisopropylcarbodiimide DCC N,N′-Dicyclohexylcarbodiimide
Step (a)
In the first step (a) an amino acid derivative of the formula II:
wherein R 1 and R 2 are as defined previously reacted with serine or threonine and the resulting dipeptide is crystallized as an ammonium salt of formula III:
wherein R 1 , R 2 , R 5 , R 6 , R 7 and R 8 are as above.
The amino acid derivatives of formula II are as a rule commercially available compounds. Suitable amino acid derivatives of formula II include, according to the preferences given for R 1 and R 2 , Fmoc-L-Ser(tBu)-OH and Fmoc-L-Thr(tBu)-OH.
Prior to the coupling with serine or threonine, the amino acid derivative of formula II is expediently activated with an activating reagent.
Suitable activating reagents can be selected from the group consisting of: DIC/HOSu, DIC/Pentafluorphenol, DIC/HOBt, DCC/HOSu, DCC/Pentafluorophenol, DCC/HOBt, EDC(xHCl)/HOSu, and HBTU/HOBt. A preferred coupling agent is DIC/HOSu. The DIC is usually used in an amount of 1.0 to 1.4 equivalents and the HOSu is usually used in an amount of 1.0 to 1.8 equivalents related to one equivalent of the amino acid derivative of formula I.
As a rule the activation reaction is performed in the presence of a suitable organic solvent, such as ethylacetate, N,N-dimethylformamide, acetone or tetrahydrofuran, preferably ethylacetate at a temperature of −5° C. to 25° C.
The coupling with serine or threonine, preferably with L-serine or L-threonine, can then be performed at a temperature of 10° C. to 30° C. in the presence of an organic solvent, such as ethylacetate, acetone or tetrahydrofuran or mixtures thereof with water. A preferred solvent is a mixture of acetone and water.
The ratio serine or threonine to amino acid derivative of formula II is usually selected in the range of 1.5 to 3.0 to 1, preferably 2.0 to 1. The pH of the reaction mixture is expediently set at a value of 7.5 to 9.0.
Step (b)
In step (b) the formation of the ammonium salt of formula III happens by adding to the dipeptide previously formed an amine of formula V:
wherein R 6 , R 7 and R 8 are independently selected from the group consisting of hydrogen, a C 1-4 -alkyl, and a C 3-7 -cycloalkyl, with the proviso that not all of R 6 , R 7 and R 8 are hydrogen. Suitable amines of formula V are those wherein R 6 , R 7 and R 8 are independently selected from the group consisting of hydrogen, ethyl and cyclohexyl, with the proviso that not all R 6 , R 7 and R 8 are hydrogen. Cyclohexylamine, dicyclohexylamine and triethylamine are the preferred amines; wherein dicyclohexylamine is the most preferred amine of formula V. The crystallization is commonly effected in suitable organic solvents such as lower alcohols like methanol, ethanol, n-propanol or i-propanol or in ethylacetate or tetrahydrofuran. A preferred solvent is ethanol.
The ammonium salts of formula III have previously not been described and thus are a further embodiment of the present invention.
Preferred ammonium salts are the dicyclohexylammonium salts of formula III wherein R 1 and R 2 are as described above, R 5 is hydrogen or methyl, R 6 is hydrogen and R 7 and R 8 are cyclohexyl.
More preferred are the compounds of formula III wherein:
a) R 1 stands for the L-serine side chain with O-tBu protection, R 2 is Fmoc, R 5 is H, R 6 is hydrogen and R 7 and R 8 are cyclohexyl. b) R 1 stands for the L-serine side chain with O-tBu protection, R 2 is Fmoc, R 5 is methyl, R 6 is hydrogen and R 7 and R 8 are cyclohexyl. c) R 1 stands for the L-threonine side chain with O-tBu protection, R 2 is Fmoc, R 5 is H, R 6 is hydrogen and R 7 and R 8 are cyclohexyl. d) R 1 stands for the L-threonine side chain with O-tBu protection, R 2 is Fmoc, R 5 is methyl, R 6 is hydrogen and R 7 and R 8 are cyclohexyl.
Step (c)
In subsequent step (c) the free acid of the dipeptide is released in the presence of an acid and the protonated amine of formula V is removed by extraction. Particularly the free acid of the ammonium salt of formula III is released in the presence of a mineral acid, taken up in an organic solvent while the amine is removed by extraction with water and/or an aqueous solution of a mineral salt.
Suitable mineral acids are aqueous sulfuric acid or aqueous HCl, preferably aqueous sulfuric acid. Suitable organic solvents for taking up the free acid can be selected from the group consisting of: ethylacetate, t-butyl methyl ether, and methylenechloride. t-Butyl methyl ether has been found to be the preferred solvent.
The organic phase containing the free acid is as a rule washed several times with water and/or an aqueous solution of a mineral salt, like sodium chloride in order to completely remove the amine.
Step (d)
In step (d) the ring closure of the free acid of the dipeptide obtained in step (c) is effected with a compound selected from the group consisting of:
wherein R 3 and R 4 are independently either hydrogen or C 1-4 -alkyl, with the proviso that not both R 3 and R 4 are hydrogen; R 9a and R 9b independently are a C 1-4 -alkyl; R 10 has the meaning of a C 1-4 -alkyl, a C 1-4 -alkanoyl, or an aryl; and R 11 is hydrogen or C 1-3 -alkyl,
in the presence of an acidic catalyst.
Preferably the ring closure is effected with compounds of the formula IVa and IVc, and more preferably with the compounds selected from the group consisting of: 2,2-dimethoxypropan, 2-methoxypropen and 2-acetoxypropen, whereby 2,2-dimethoxypropan is the most preferred compound.
Ideally the compounds of formula IV are used in an amount of 6.0 to 16.0 equivalents, preferably 7.0 to 10.0 equivalents in relation to the dipeptide obtained in step (c).
Suitable acidic catalysts are selected from the group consisting of: methane sulfonic acid, (+) camphor-10-sulfonic acid, p-toluenesulfonic acid, and pyridinium p-toluenesulfonate, most preferably methane sulfonic acid. The acidic catalyst is usually applied in an amount of 0.05 to 0.30 equivalents, preferably 0.10 to 0.20 equivalents in relation to the dipeptide obtained in step (c).
The ring closure is effected in the presence of an organic solvent, such as in tetrahydrofuran, methylenechloride or toluene, preferably in tetrahydrofuran at reflux temperature.
Isolation and work up of the target product can be performed by using methods which are known to the skilled in the art.
The following examples illustrate the invention without limiting it.
EXAMPLES
Example 1
A 1000 mL double jacketed glass reactor equipped with a mechanical stirrer, a Pt-100 thermometer, reflux condenser, a dropping funnel and a nitrogen inlet was charged with 25 g (64.9 mmol) of Fmoc-L-Ser(tBu)-OH (1), 9.66 g (83.1 mmol) of N-hydroxysuccinimide and 180 mL of ethyl acetate. The resulting suspension was cooled to 0° C. A solution of 10.49 g (83.1 mmol) of diisopropyl carbodiimide in 20 mL of ethyl acetate was added within 15 minutes. The resulting mixture was stirred at 0° C. for 2 h and then for another hour at room temperature and sampled. The solvent was completely removed under reduced pressure (ca. 220 mbar) at a jacket temperature of maximal 50° C. The residue was treated with 250 mL of acetone at an internal temperature of 35° C. to 40° C., cooled to 20° C. and treated with 13.5 mL of water. The pH was set with 1.0 mL of 1 M HCl to pH 2-3 and the resulting mixture was stirred for 12 h at 20° C. and sampled. The suspension was then cooled to −5° C. to 0° C. and stirred for 1 h at this temperature. The precipitate was filtered off and the reactor and filter was rinsed with 50 mL of cold acetone (0° C.). The clear and colorless filtrate was added at 20° C. within 60 minutes to a solution of 13.57 g (127.8 mmol) of L-serine and of 13.63 g (257 mmol) of sodium carbonate in 122.5 ml of water. The resulting mixture was stirred for 1 h at 20° C. and sampled. The pH was set with 28 g of HCl (37%) to pH 2-3 and the organic solvent was removed under reduced pressure (<250 mbar) at a jacket temperature of maximal 50° C. The resulting suspension was treated at 35° C. to 40° C. with 125 mL of ethyl acetate and the resulting clear biphasic solution was cooled to 20° C. The phases were separated and the organic phase was twice extracted with totally 250 mL of ethyl acetate. The combined organic layers were three times washed with totally 225 mL of aqueous NaCl (10% w/w). The resulting organic solution was concentrated and the solvent almost completely removed under reduced pressure at a jacket temperature of maximal 50° C. The residue was dissolved in 250 mL of ethanol where after a part of the solvent (75 mL) was removed again under reduced pressure (ca. 170 mbar) at a jacket temperature of maximal 50° C. The resulting solution was treated with 462.5 mL of ethanol and cooled to 20° C. About 20% (ca. 29.5 mL) of a solution of 11.83 g (63.9 mmol) of dicyclohexylamine in 118 mL of ethanol was added. The mixture was seeded whereupon the product started to precipitate. The suspension was stirred for 1 h at RT and subsequently, the rest of the dicyclohexyl amine solution was slowly added within at least 2 h. The dropping funnel was rinsed with 25 mL of ethanol. The internal temperature was lowered to 0° C. within 4 h where after the suspension was stirred over night at this temperature. The precipitate was filtered with suction, the filter cake was washed with 117.5 mL of cold ethanol (0° C.) and dried under vacuum (50° C., 20 mbar) to afford 35.7 g (yield 82% starting from (S)-3-tert-Butoxy-2-(9H-fluoren-9-ylmethoxycarbonyl-amino)-propionic acid, 96.8% (w/w) purity based on HPLC) of (S,S)-2-[3-tert-Butoxy-2-(9H-fluoren-9-ylmethoxycarbonylamino)-propionyl-amino]-3-hydroxy-propionic acid dicyclohexyl-ammonium salt (3) as a colorless solid.
The HPLC analysis was performed using an external standard of pure (S,S)-2-[3-tert-Butoxy-2-(9H-fluoren-9-ylmethoxycarbonylamino)-propionyl-amino]-3-hydroxy-propionic acid dicyclohexyl-ammonium salt (3). Conditions for HPLC: Column XBridge C18 (Waters), 4.6×150 mm, 3.5 μm; UV detection 206 nm; solutions for gradient: water (A), 20 mM KH 2 PO 4 -buffer, pH 2.5 (B), acetonitrile (C); flow 1.0 mL/min; 20° C.
Gradient:
T[min] A[%] B[%] C[%] 0 45 15 40 2 45 15 40 14 5 15 80 25 5 15 80
Retention Times:
(S,S)-2-[3-tert-Butoxy-2-(9H-fluoren-9-ylmethoxycarbonylamino)-propionyl-amino]-3-hydroxy-propionic acid dicyclohexyl-ammonium salt (3) 8.4 min Fmoc-L-Ser(tBu)-OH (1) 11.6 min
This HPLC-method results in a value for the assay of the free acid of (3). From this value, the assay of the corresponding dicyclohexylammonium salt is calculated, assuming a stoichiometric ratio of 1:1 of free acid and dicyclohexyl ammonium.
A GC analysis using an internal standard of dodecane is used to measure the content of dicyclohexyl amine. Conditions for GC: Column fused silica, 100% polydimethylsiloxane, 1 μm, L=15 m, ID=0.25 mm; carrier gas hydrogen, pressure: 53 kPa, lin. velocity: 73 cm/s, split-ratio: 1:100.
Temperature Program:
Heating end- duration of isothermal rate temperature step at end- [° C./min] [° C.] temperature [min] 0.0 40 1 50 240 5 0.0 320 10
Retention Times:
Dodecane 4.10 min
Dicyclohexylamine 4.90 min
Example 2
A 500 mL double jacketed glass reactor equipped with a mechanical stirrer, a Pt-100 thermometer, reflux condenser, a dropping funnel with cotton filter, and a nitrogen inlet was charged with 25.0 g (37.0 mmol) of (S,S)-2-[3-tert-Butoxy-2-(9H-fluoren-9-ylmethoxycarbonylamino)-propionylamino]-3-hydroxy-propionic acid dicyclohexylammonium salt (3), 100 mL of tert-butyl methyl ether and a solution of 4.70 g of sulfuric acid (96%) in 44.3 mL of water. The mixture was stirred for 90 minutes at room temperature. The aqueous phase was separated and the organic phase was twice washed with a total of 76 ml of aqueous sodium chloride (0.5%-w/w) and again with 38 mL of water. The organic solvent was completely removed under reduced pressure (500-100 mbar) and at a jacket temperature of 50° C. The foamy residue was dissolved in 100 mL of tetrahydrofuran and the solvent was again completely removed reduced pressure (500-100 mbar) and at a jacket temperature of 50° C. The residue was dissolved in 450 ml of tetrahydrofuran and the resulting clear solution was treated with 35.4 g (333 mmol) of 2,2-dimethoxy propane and 0.65 g (6.7 mmol) of methanesulfonic acid. The mixture was heated under reflux at a jacket temperature of 85° C. while leading back the distillate over 73 g of molecular sieve (0.4 nm). After 16 h, the slightly yellowish solution was cooled to 20° C. and sampled, and the mixture was treated with 0.828 g (8.14 mmol) of triethylamine and stirred for 10 minutes. The solvent was completely removed under reduced pressure (350-100 mbar) and at a jacket temperature of 50° C. The residue was treated with 100 mL of tert-butyl methyl ether and again completely concentrated under reduced pressure (350-100 mbar) and at a jacket temperature of 50° C. The residue was dissolved in 175 mL of tert-butyl methyl ether and cooled to 20° C. to 25° C. The solution was treated with 87.5 mL of water and stirred for 10 minutes. The phases were separated and the organic phase was completely concentrated under reduced pressure (350-100 mbar) and at a jacket temperature of 50° C. The foamy residue was dissolved in 100 mL of tert-butyl methyl ether and completely concentrated under reduced pressure (350-100 mbar) and at a jacket temperature of 50° C. This step was twice repeated with a total of 200 mL of tert-butyl methyl ether. The residue was dissolved in 45.2 mL of tert-butyl methyl ether at 20° C. to 25° C. and treated with 22.6 mL of Isopropanol. At this temperature, the solution was treated with 175 mL of pentane, seeded, then kept stirring for at least 15 minutes, and again slowly treated with 200 mL of pentane within 1 h. The resulting solution stirred for 4 to 16 h and then cooled to 0° C. within 1-2 h and again stirred for another 2 h at this temperature. The precipitate was filtered with suction, the filter cake washed in two portions with a total of 60 ml of cold pentane (0° C.) and dried under vacuum (50° C., 20 mbar) to afford 14.3 g (yield 75% starting from (S,S)-2-[3-tert-Butoxy-2-(9H-fluoren-9-ylmethoxycarbonylamino)-propionylamino]-3-hydroxy-propionic acid dicyclohexyl-ammonium salt, 98.7% (w/w) purity based on HPLC) of (S,S)-3-[3-tert-Butoxy-2-(9H-fluoren-9-yl-methoxycarbonylamino)-propionyl]-2,2-dimethyl-oxazolidine-4-carboxylic acid (4) as a colorless solid.
The HPLC analysis was performed using an external standard of pure (S,S)-3-[3-tert-Butoxy-2-(9H-fluoren-9-yl-methoxycarbonylamino)-propionyl]-2,2-dimethyl-oxazolidine-4-carboxylic acid (4). Conditions for HPLC: Column XBridge C18 (Waters), 4.6×150 mm, 3.5 μm; UV detection 206 nm; solutions for gradient: water (A), 20 mM KH 2 PO 4 -buffer, pH 2.5 (B), acetonitrile (C); flow 1.0 mL/min; 20° C.
Gradient:
T[min] A[%] B[%] C[%] 0 27 15 58 1 27 15 58 6 20 15 65 10 5 15 80 20 5 15 80 20.1 70 15 15 25 70 15 15
Retention Times:
(S,S)-3-[3-tert-Butoxy-2-(9H-fluoren-9-yl-methoxycarbonylamino)-propionyl]-2,2-dimethyl-oxazolidine-4-carboxylic acid (4) 7.3 min (S,S)-2-[3-tert-Butoxy-2-(9H-fluoren-9-ylmethoxycarbonylamino)-propionyl-amino]-3-hydroxy-propionic acid dicyclohexyl-ammonium salt (3) 3.0 min Fmoc-L-Ser(tBu)-OH (1) 5.6 min
Unless stated to the contrary, all compounds in the examples were prepared and characterized as described. All ranges recited herein encompass all combinations and subcombinations included within that range limit. All patents and publications cited herein are hereby incorporated by reference in their entirety. | Disclosed is a process for the manufacture of pseudo proline dipeptides of the formula
wherein R 1 is a side chain of an alpha amino acid, R 2 is an amino protecting group and R 3 and R 4 are independently either hydrogen or C 1-4 -alkyl, and R 5 is hydrogen or methyl starting from an amino acid derivative of the formula
wherein R 1 and R 2 are as defined above. Pseudo proline dipeptides can be used as reversible protecting groups for Ser, Thr and Cys and thus are versatile tools in peptide chemistry. | 8 |
FIELD
[0001] The present invention pertains to a sealing tape of soft foam.
BACKGROUND
[0002] Sealing tapes of soft and flexible foam material are used in the construction industry to provide a seal against drafts and driving rain. For household use by the end user, there are generally known foam tapes with a thickness of usually a few millimeters, which are provided on one side with a layer of a pressure-sensitive adhesive covered by a cover film and are wound up uncompressed into rolls. They are used between window or door panels and the window or door frames to seal leaky windows and doors. For this purpose, they are adhered to suitable points on the panel or frame.
[0003] In the professional building construction industry, sealing tapes, usually impregnated, of soft and flexible foam material are used between window and door frames and the masonry. These types of sealing tapes can be up to a few centimeters thick and are usually provided on one side with a self-adhesive layer, by means of which they can be adhered to the frame profile elements of windows and doors. So that a component which has been provided with the sealing tape can be installed more easily at the construction site, sealing tapes of this type are frequently impregnated with a material which delays the recovery of the foam material from its compressed state, i.e., the state in which it has been delivered on a roll, back to the expanded state.
[0004] To prevent the diffusion of vapor, it is necessary to use sealing tapes of the previously mentioned type which have been provided with a vapor barrier. A sealing tape of open-pored material which has been rolled up into a disk and which is used to seal joints or gaps against drafts and driving rain is known from DE 196 41 415 C2, in which at least one barrier layer is arranged inside the sealing tape in such a configuration that it and the adjacent open-pored areas form a row in the axial direction. The barrier layer therefore extends in the radial direction of the sealing tape roll.
[0005] WO 98/45565 shows a sealing tape with a removable film coating, which covers three sides of the sealing tape in the compressed state.
SUMMARY
[0006] It is an object of the present invention to provide an easy-to-produce sealing tape equipped with a film strip.
[0007] According to an aspect of the invention, the sealing tape roll comprises a soft foam strip of rectangular cross section formed into a roll, which strip has two outer lateral surfaces, a top surface, and a bottom surface, and at least one film strip, which covers at least one of the lateral surfaces of the soft foam strip. Two portions of the film strip are attached, and preferably bonded adhesively, to the soft foam strip, wherein at least one of the portions is located on the bottom surface or on the top surface of the soft foam strip and is arranged between adjacent turns within the roll.
[0008] A basic distinction can be made between sealing tapes of soft, flexible foam material which are delivered in the compressed state and those which are delivered in the uncompressed state. The invention can be applied in principle in almost the same way to both types of tape.
[0009] The film strip is either attached to at least one lateral surface or adhered by one of its edge portions to the bottom surface of the foam strip. Preferably, the bottom surface of the foam strip is used to adhere the sealing tape to the structural element to be sealed, such as a frame profile element of a window or door. The bottom surface of the foam strip can be provided with a self-adhesive layer, which then also holds the film strip in place.
[0010] The film strip is wide enough to extend completely over the adjacent exposed lateral surface of the sealing tape even after the structural component has been installed, i.e., after the foam strip, which forms the main component of the sealing tape, has partially re-expanded.
[0011] The film strip preferably used is a vapor barrier film. The film strip, however, can also be a UV barrier film, which is intended to protect the foam material covered by it from the effects of UV rays. Films which are selected from an aesthetic standpoint, such as metallized or colored films, are also contemplated. In a preferred embodiment, the sealing tape of the present invention may include any type of film-like, flexible tape material, which is selected according to the individual requirements, including textile materials or laminates with several layers.
[0012] A significant advantage of the sealing tape according to preferred embodiments of the invention is that a completely mobile system is created, consisting of a soft, elastic foam strip and a film strip, wherein the film strip is formed into a loop in such a way that it can move across the entire functional area of the sealing tape. When the soft foam strip expands as a result of its elastic recovery after installation on a structural element, the reserve film strip material provided by the loop is available for movement along the lateral surface of the soft foam strip and is used up without the need for the film strip itself to stretch.
[0013] In contrast to the conventional method, the sealing tape according to the present invention can be produced in the form of narrow sealing tape rolls, also called sealing tape disks because of their dimensions, without the need for special measures to prepare the foam material for the production of the sealing tape disks. Instead, the process calls for providing such sealing tape disks with a flexible film, such as a vapor barrier film, in the form of a film strip, after the disks have been produced.
[0014] If, for example, the original height of the foam strip of the sealing tape is 30 mm and it has been compressed to a height of 4-5 mm in the roll, the manufacturer frequently limits its area of application to gaps, which are to be bridged by the sealing tape, of a certain width such as 15 mm. The reason for this is that, if the foam material were to be allowed to expand more than that, it would not rest tightly against the wall of the building.
[0015] The functional range of the sealing tape, which determines the width of the film strip to be selected, is therefore determined by the degree of compression of the foam material within the roll and the maximum recovery of the foam material after installation of the structural element to which the tape has been applied. The minimal thickness after compression of impregnated foam materials is currently about 10% of the original thickness. The recovery capacity after compression is sometimes not enough to allow the foam to return to its original thickness.
[0016] To ensure the sufficiently reliable adhesion of the film strip to the foam material of the sealing tape, it is sufficient that two portions of the film strip, each approximately 1-2mm wide, are attached, preferably adhesively by means of a self-adhesive layer, to the foam material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Additional properties, features, and advantages of the invention can be derived from the detailed description below based on the drawings, which show in schematic fashion cross sections of several exemplary embodiments of sealing tapes according to the invention:
[0018] FIG. 1 shows a first embodiment of the sealing tape according to the invention in the wound-up, compressed state,
[0019] FIG. 2 shows the sealing tape of FIG. 1 in the partially compressed, functional state, and
[0020] FIG. 3 shows a second embodiment of the sealing tape according to the invention in the wound-up, compressed state.
DETAILED DESCRIPTION
[0021] All of the drawings show a foam strip, an adhesive layer, the film strip, and part of the cover film in a way which makes it appear that they are a certain distance apart from each other. This is to illustrate more clearly how these elements are positioned with respect to each other. It should therefore be emphasized that the elements are resting right on top of each other and are pressed onto each other and are thus in mutual contact. It should also be emphasized that all the figures show cross sections of a sealing tape. FIGS. 1 and 3 show the state which is to be found when the sealing tape is wound up in the compressed state on a winding core.
[0022] FIG. 1 depicts a foam strip 1 , which is shown in the compressed state. In this state, it has a flat, rectangular cross section and is provided with a first layer 2 a of pressure-sensitive adhesive on one side, which is to be referred to as the “bottom surface” here and in the case of all the illustrated preferred embodiments to be explained below. This self-adhesive layer 2 a is shown in broken line. A portion 5 a of a film strip 3 is attached to the bottom surface of foam strip 1 by means of this first self-adhesive layer 2 a. Film strip 3 is guided upward across a lateral surface 1 a and around foam strip 1 , formed into a loop 7 on the top surface of foam strip 1 , and attached, preferably adhesively, to the top surface of foam strip 1 by a portion 5 b near lateral surface 1 a. Portion 5 b is attached preferably by means of a second self-adhesive layer 2 b, but, like the attachment of portion 5 a, it can also be done by means of some other type of adhesive.
[0023] Portion 5 a of film strip 3 adheres to self-adhesive layer 2 a can and be provided with a plurality of openings or holes. On the bottom surface of foam strip 1 , film strip 3 is covered by a cover film 4 to prevent the various layers of a coil from sticking together. The openings or holes in film strip 3 are large enough that, by pressing cover film 4 down, it can be adhered through the holes of the film strip to self-adhesive layer 2 a. Alternatively, if portion 5 a of film strip 3 does not comprise any openings, cover film 4 can extend only up as far as portion 5 a.
[0024] Loop 7 forms the expansion reserve and simultaneously defines the maximum degree of expansion. As film strip 3 is formed into a loop, the film strip slides very easily over itself as the foam expands.
[0025] In the present exemplary embodiments, both portions 5 a, 5 b of film strip 3 are bonded to the foam, i.e., one to the bottom surface, the other to the top surface, and thus lie, when in the rolled-up state, between different layers of the roll. It is also possible, however, to bond one of the two portions 5 a, 5 b to the upper or lower edge of the lateral surface 1 a, as long as the overall lateral surface 1 a remains covered by film strip 3 .
[0026] FIG. 2 shows the sealing tape of FIG. 1 in the partially expanded, functional state.
[0027] FIGS. 1 and 2 thus illustrate the operation of the sealing tape of the present invention. FIG. 1 shows the state of the sealing tape on the roll, although the roll itself is not shown. This is also the state in which the sealing tape is found immediately after it has been taken from the roll, provided that foam strip 1 has been impregnated with a recovery-delaying agent. Over the further course of time, foam strip 1 expands upward due to the elastic recovery force intrinsic to the foam material. This has the result that, in the area of loop 7 , film strip 3 rolls over itself and slides across the upper edge between the lateral surface 1 a covered by film strip 3 and the top surface of foam strip 1 . At the end of the allowed expansion of foam strip 1 , film strip 3 has slid almost completely off the top surface of foam strip 1 ( FIG. 2 ) but is held in place by the adhered area in portion 5 b and thus covers the entire lateral surface 1 a of foam strip 1 . This is the state which is present, for example, after a structural frame element equipped with the sealing tape has been installed in an opening in a building and has been sealed off by the sealing tape against the opening. It should be pointed out, however, that in this case cover film 4 has been pulled off, because the sealing tape is adhered to the frame element in question by means of self-adhesive layer 2 .
[0028] FIG. 3 shows two layers of another embodiment of the sealing tape according to the invention, in which no cover film 4 is required. In this embodiment, portion 5 b of the film strip 3 is adhered to the entire top surface of foam strip 1 , and its outside-facing surface in this area is siliconized, as a result of which it assumes the function of cover film 4 . Film strip 3 can project slightly beyond the free lateral surface.
[0029] Loop 7 formed in the area of covered lateral surface 1 a. In addition, loop 7 can be bonded in that area with an adhesive 6 which releases only with a certain delay and which allows foam strip 1 to expand but only at the rate determined by adhesive 6 just mentioned. In addition, such an adhesion point also makes it easier to handle the sealing tape, because loop 7 cannot unfold in an undesirable manner.
[0030] While the invention has been described and illustrated in conjunction with specific preferred embodiments, it will be evident that many alternatives, modifications, variations and combinations will be apparent to those skilled in the art. Any such changes may be made without departing from the spirit and scope of the invention. The described and illustrated embodiments are to be considered in all respects only as illustrative and not restrictive. These and all similar modifications and changes are considered to be within the scope of the present invention. | A sealing tape roll comprising a soft foam strip ( 1 ) of rectangular cross section formed into a roll with two outer lateral surfaces ( 1 a ), a top surface, and a bottom surface, and at least one film strip ( 3 ), which covers at least one of the lateral surfaces ( 1 a ) of soft foam strip ( 1 ). Two portions (5 a, 5 b ) of film strip ( 3 ) are attached adhesively to soft foam strip ( 1 ), wherein at least one of the portions ( 5 a, 5 b ) is located on the bottom surface or top surface of soft foam strip ( 1 ) and is arranged between adjacent turns within the roll. | 8 |
FIELD OF INVENTION
The present invention relates in general to delta-sigma data converters, and, in particular, to data converters with digitally filtered pulse width modulation output stages and methods and systems using the same.
BACKGROUND OF INVENTION
Delta-sigma modulators are particularly useful in digital to analog and analog to digital converters (DACs and ADCs). Using oversampling, the delta-sigma modulator spreads the quantization noise power across the oversampling frequency band, which is typically much greater than the input signal bandwidth. Additionally, the delta-sigma modulator performs noise shaping by acting as a lowpass filter to the input signal and a highpass filter to the noise; most of the quantization noise power is thereby shifted out of the signal band.
The typical delta sigma modulator includes a summer summing the input signal with negative feedback, a loop filter, a quantizer, and a feedback loop coupling the quantizer output and the inverting input of the summer. In a first order modulator, the loop filter includes a single integrator or other filter stage while the loop filter in a higher order modulator has a cascade of a corresponding number of filter stages. Higher-order modulators have improved quantization noise transfer characteristics over those of lower order, but stability becomes a more critical design factor as the order increases. The quantizer can be either a one-bit or a multiple-bit quantizer.
In DAC applications, such as low out-of-band noise DACs, continuous-time output stages, such as current summers, which convert the quantized modulator output into a relatively smooth analog signal have a number of advantages over discrete-time output stages, such as switched capacitor output stages. For example, in DAC systems in which the modulator output is quantized into a large number of levels (e.g. sixty-four or more levels represented by eight or more bits), continuous-time output stages are relatively easy to design and construct. In addition, continuous-time output stages operating on a large number of quantization levels are relatively immune to jitter and the problem of sampling of far out-of-band energy. These advantages make continuous-time output stages the best choice for integration into large digital chips. With respect to smaller data converters and coder-decoders (Codecs), avoiding the sampling of high frequency energy allows for the simplification of the clock management scheme.
Despite their advantages, continuous-time output stages are also subject to significant drawbacks, such as a susceptibility to inter-symbol interference. (Inter-symbol interference or ISI in this case is usually caused by asymmetry in leading and trailing edges of the output signals from continuous time elements or from analog memory, in which each symbol is dependent on the prior one.) ISI can dominate the noise and distortion components in the output analog stream of a continuous-time data converter, even if a large number of continuous-time conversion elements operate on data samples with a large number of quantization levels. While ISI can be minimized using return to zero (RTZ) techniques, RTZ techniques generally cause increased circuit sensitivity to the characteristics of the controlling clocks.
Therefore, improved circuits and methods are required which allow continuous-time output stages to be utilized in such applications as DACs while minimizing ISI and at the same time reducing the effects of clock characteristics on circuit performance.
SUMMARY OF INVENTION
According to one particular embodiment, a digital to analog converter is disclosed including a noise shaping modulator for modulating an input digital data stream, a plurality of output elements for generating a plurality of intermediate data streams from a modulated output stream from the modulator, and an output summer for summing the intermediate data streams to generate an output analog stream. The noise shaping modulator balances an edge transition rate of the output elements, such that the edge transition rate of two selected elements is approximately equal. By balancing the edge transition rate of the elements, the effects of ISI are largely eliminated.
Application of the present inventive principles provides for the design and construction of digital data converters, in particular DACs, utilizing continuous-time output elements with minimal susceptibility to ISI and clock vagaries. Generally, a duty-cycle modulator receives a digital input stream and generates a duty-cycle, pulse width modulated (PWM) encoded data stream. A finite impulse response (FIR) filter removes the fundamental frequency and harmonics of the PWM rate from the duty cycle modulated stream. By tapping the stages of the FIR filter with a plurality of digital to analog conversion elements, in either a continuous-time or discrete-time manner, an analog output signal is generated with reduced distortion due to jitter of ISI. In one particular embodiment, multiple pulse width modulator stages are interleaved in time to generate multiple time-overlapping PWM-encoded data streams. These overlapping PWM-encoded data streams drive multiple conversion elements with matched utilization and transition rates. A delta-sigma modulator with multiple attenuation bands in front of the interleaved PWM stages attenuates noise that would otherwise be demodulated by mismatch between the analog stages. A FIR filter coupled after each interleaved PWM stage removes out of band energy caused by the PWM process.
BRIEF DESCRIPTION OF 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. 1A is high level block diagram of an exemplary digital audio system including a digital to analog converter utilizing a delta-sigma modulator with multiple attenuation bands and interleaved pulse width modulators according to the inventive principles;
FIG. 1B is a more detailed block diagram of an exemplary digital-in, analog-out finite impulse response (FIR) filter suitable for use in the exemplary analog-in, digital-out FIR blocks shown in FIG. 1A;
FIG. 2A is a gain versus frequency plot of the noise transfer function (NTF) of an exemplary delta-sigma modulator with four noise attenuation bands suitable for use in selected embodiments of the data converter of FIG. 1 utilizing four interleaved pulse width modulators;
FIG. 2B is a plot in the z-plane of the poles and zeros of a delta-sigma modulator with multiple NTF noise attenuation bands corresponding to the noise attenuation bands shown in FIG. 2A;
FIGS. 2C-2E are block diagrams of exemplary feedforward delta-sigma modulators suitable for producing the pole-zero placements shown in FIG. 2B;
FIG. 3 is a timing diagram illustrating the signal timing of representative operations of the delta-sigma modulator and pulse width modulators shown in FIG. 1 for the exemplary by-four interleaved pulse width modulator;
FIG. 4 is a gain versus frequency plot of the output of a selected one of the pulse width modulators of FIG. 1 for the exemplary by-four interleaved PWM and the response of the associated finite impulse response output filter;
FIG. 5 is a high level operational block diagram of an exemplary digital to analog converter utilizing interleaved noise shapers and corresponding digital output filters according to the inventive principles.
DETAILED DESCRIPTION OF THE INVENTION
The principles of the present invention and their advantages are best understood by referring to the illustrated embodiment depicted in FIGS. 1-5 of the drawings, in which like numbers designate like parts.
FIG. 1A is a high-level functional block diagram of an exemplary digital to analog converter system 100 suitable for demonstrating the principles of the present invention. For purposes of discussion, an audio application is described operating on digital audio from a source 101 such as a compact disk (CD) or digital versatile disk (DVD) player; however, the concepts described below can be utilized in a wide range of circuits and systems requiring digital to analog conversion. In system 100 , the data output from digital source 101 is multiple-bit audio data having a base sampling frequency (rate) fs and oversampled by an oversampling factor K. For example, in the illustrated embodiment the audio stream is output from digital audio source 101 with a base sampling frequency (fs) of 48 kHz with sixty-four times (64×) oversampling (i.e., K=64).
System 100 is based on a multiple-bit noise shaper 102 (e.g. delta sigma modulator) with multiple attenuation bands in the noise transfer function (NTF). Noise shaper 102 will be discussed in detail further below; however, generally the NTF includes one attenuation band for attenuating noise in the signal passband and additional attenuation bands for attenuating noise, which would otherwise be demodulated by any non-zero mismatch between the following pulse width modulation (PWM) stages 104 in the multiple PWM stage embodiments discussed below.
Noise shaper 102 in the illustrated embodiment outputs multi-bit quantized samples at an oversampling frequency L·fs, in which L is the oversampling ratio of noise shaper 102 . The modulation index (MI) of noise shaper 102 is preferably set to ensure that full scale output quantization levels are not output to the following PWM stages 104 . However, in alternate embodiments, in which some level of the ISI in the output stream is tolerable, full-scale quantization levels are utilized.
Each one-bit sample output from noise shaper 102 is interleaved by 1 to N interleave circuitry 103 into a corresponding one of a set of N parallel PWM stages, in which N is an integer greater than or equal to 1. In FIG. 1A, representative pulse width modulation (PWM) stages 104 a to 104 N, are shown for discussion purposes. Each PWM stage 104 a to 104 N therefore effectively operates on input samples at a rate of L/N·fs. Exemplary PWM stages suitable for use as PWM stages 104 a to 104 N of system 100 are described in coassigned U.S. Pat. No. 6,150,969 to Melanson, entitled Correction of Nonlinear Output Distortion In a Delta Sigma DAC, and U.S. Pat. No. 5,815,102 to Melanson, entitled Delta Sigma PWM DAC to Reduce Switching, both of which are incorporated herein by reference. Interleave circuitry 103 is an exemplary circuit. A typical implementation for PWM stages 104 a , 104 b may be to connect them to noise shaper 102 and allow them to only be responsive to the appropriate samples from noise shaper 102 . If N was 2, for example, PWM stage 104 a would be responsive only to the even samples from noise shaper 102 , and PWM stage 104 b would only be responsive to only the odd samples.
In the illustrated embodiment of system 100 , each of PWM stages 104 a to 104 N operates with an oversampling factor M and an oversampling clock signal at an oversampling frequency M·(L/N)fs. Each PWM stage therefore outputs M number of N/(M·L) clock period long PWM patterns representing (M+1 levels) per sample received from interleave circuitry 103 . In addition to the energy in the signal base band (approximately 0 to fs/2), each PWM stage 104 a to 104 N also outputs significant energy at the fundamental frequency and harmonics of the PWM repeat rate of L/N·fs. Hence, each PWM stage 104 a to 104 N is followed by a digital-in, analog-out finite impulse response (FIR) filter with attenuation bands corresponding to these harmonics. Representative FIR filters 105 a to 105 N are shown in FIG. 1 A. The analog outputs from FIR filters are summed into output summer 106 to generate the analog output.
By this series of operations, system 100 ensures that the usage of all output elements 111 a , . . . ,N of FIR filters 105 a to 105 N (discussed below) is approximately the same, as guaranteed by multiple NTF zeros of delta-sigma noise shapers 102 , (also discussed further below). In alternate embodiments, other techniques, such as independent delta-sigma modulators, may be used. In addition, by this construction of system 100 , the edge rate of all of the elements 111 a - 111 b is also approximately equal. This result is due to a side effect of the fixed edge rate of combined delta-sigma modulators and pulse width modulators in general. Taken together, these two constraints remove much of the source for distortion in analog output stages. Other techniques for directly balancing the edge rates are possible in alternate embodiments. As an example, the edge rate could be monitored, and the transitions probability modified in response.
FIG. 1B illustrates exemplary embodiments of digital-in, analog-out FIR filters 105 a to 105 N in further detail. Each filter 105 a to 105 N includes a conventional FIR filter, such as a boxcar filter with simple coefficients, with X number of output taps. The length (number of stages) of each FIR filter 105 a to 105 N is greater than or equal to the width of the PWM pattern from the preceding PWM stage 104 a to 104 N, which introduces a notch in the filter output transfer function corresponding to the fundamental of the PWM repeat frequency. In other words, the length of each FIR filter 105 a to 105 N is proportional to the ratio of the output frequency of the FIR filter to the input frequency of the FIR filter. Longer FIR filters 105 a to 105 N (e.g. FIR filters with more stages) will attenuate more out of band energy at the cost of increased number of elements. Using FIR filters 105 a to 105 N with equal weights, the number of taps equal to the PWM pattern length, is an easy technique to significantly reduce out of band energy.
Each of the x number of filter taps, (in which x is an integer greater than one) is associated with a current source or similar single-bit digital to analog conversion elements, two of which are shown at 111 a and for each filter 105 a to 105 N. Current sources 111 a , . . . ,N are of a simple constructions, such as a voltage source and a resistor or transistors operating in a constant current region or cascoded transistors. The outputs from current sources are either single-ended or differential sources. In the illustrated embodiment, output summer 106 includes a current to voltage converter when single-bit digital to analog conversion is performed by current sources 111 a , . . . ,N. The currents can be equal, as in a boxcar filter, or unevenly weighted. Advantageously, boxcar embodiments of FIR filter 105 a to 105 N, with equal taps are the simplest to implement and are adequte for most purposes.
In audio system 100 , the analog output signal generated by summer 106 is subject to additional conventional analog filtering and amplification in analog filtering and amplification circuit block 107 . A headset or set of speakers 108 provides the audible output.
The operation of noise shaper 102 for a by-four (i.e. N=4) interleaved system 100 is illustrated in FIGS. 2A and 2B. If N=4, noise shaper 102 outputs quantized samples that are split into four (4) sample streams each at a frequency of L·fs/4. In this example, noise shaper 102 outputs data samples at an oversampling frequency 128 fs, and interleave circuitry 103 therefore splits the noise shaped data stream into four streams, each at a frequency of 32fs. Any mismatch between the following PWM stages 104 a to 104 N therefore demodulates the noise in the modulator bands 128·fs/4, 128·fs/2 and 128·3fs/4 (respectively 32fs, 64fs and 96fs). Advantageously, the use of a PWM stage 105 a to 105 N in each output increases the effective matching accuracy of the following DAC elements, since the effect of the output mismatch is reduced by the number of slots in the PWM up-sampling.
As shown in FIG. 2A, the noise exposed to any non-zero mismatch between PWM stages 104 a , . . . ,N, is minimized by three additional attenuation bands included in the noise transfer function (NTF) of noise shaper 102 about the frequencies 32fs, 64fs and 96fs along with the noise attenuation band at the signal baseband. The difference between the average level of attenuation in the signal band and the average level attenuation at the frequencies 32fs, 64fs, and 96fs depends on the mismatch between the following PWM stages 104 a to 104 N. If more mismatch exists, then more modulator noise is demodulated in the frequencies bands about 32fs, 64fs and 96fs, and the more attenuation in the modulator NTF around the frequencies 32fs, 64fs and 96fs is required. However, an increase in attenuation at the frequencies 32fs, 64fs and 96fs results in a decrease in attenuation in the signal band. (Generally, the area below the x-axis of FIG. 2A must equal the area above the x-axis.) Thus, a balancing must be made between the global noise shaping of the NTF across the modulator output frequency spectrum and local attenuation levels around 32 fs, 64 fs, and 96fs.
An NTF in noise shaper 102 with a given difference between the average attenuation level in the signal band and the average attenuation about the frequencies 32fs, 64fs and 96fs needs to be produced. A noise shaper topology which produces a one set of pole—zero pairs for setting the NTF signal band attenuation and sets of fewer poles about the frequencies 32fs, 64fs and 96fs is required. A z-plane plot of the pole and zeros characterizing one such noise shaper is shown in FIG. 2 B. In this example, an 11 th order noise shaper is characterized, which includes a first set 20 of five (5) pole-zero pairs that define the shape of the low frequency (signal band) noise attenuation of the NTF. In the illustrated embodiment, pole-zero pair set 20 includes four (4) pole-zero pairs at Butterworth locations and one (1) real pole-zero pair. Three additional sets 21 , 22 , and 23 of poles respectively define the shape of the noise attenuation bands about the frequencies 32fs, 64fs, and 96fs. The number of poles and zeros in each set 20 - 23 may vary between embodiments, depending on the desired noise shaping desired and the tradeoff between the attenuation level in the NTF signal band and the attenuation levels in the 32fs, 64fs, and 96fs frequency bands of the NTF. In FIG. 2B, the NTF zeros at 32fs, 64fs and 96fs are split along the unit circle in the z-plane. In alternate embodiments, these zeros may remain un-split (co-located) to reduce the amount of hardware required to implement noise shaper 102 .
Exemplary delta sigma modulator (noise shaper) topologies, which generate multiple attenuation bands in the NTF and which are suitable for use in noise shaper 102 are described in copending and coassigned patent application entitled “DELTA-SIGMA MODULATION CIRCUITS AND METHODS UTILIZING MULTIPLE NOISE ATTENUATION BANDS AND DATA CONVERTERS USING THE SAME” (U.S. Ser. No. 0/191,016,) incorporated herein by reference. For example, the z-plane pole-zero plot shown in FIG. 2B may be achieved by using the interleaved modulator topology 200 shown in FIGS. 2C and 2D, and discussed briefly below. Alternatively, a feed-forward design may be utilized having five filter stages with a transfer function of 1/(1−Z −1 ), and associated feedback loops, which place poles and zeros about the Z=0 point and a pair of filter stages with a transfer function of 1/( 1−Z −4 ), and associated feedback loops, which place poles and zeros about the z-plane points Z=1,−1, j and −j. A feedback modulator may be used in other embodiments, although a feedback topology requires more precise coefficients and additional hardware. A general discussion of delta-sigma modulator topologies, including feedforward designs, is be found in publications such as Norsworthy et al., Delta - Sigma Data Converters, Theory, Design and Simulation, IEEE Press, 1996).
In exemplary modulator topology 200 , shown in FIGS. 2C, the local noise shaping at the frequencies fs/4 (z-plane point Re=0, Im=j), fs/24 (z-plane point Re=−1, Im=0) and 3fs/4 (z-plane point Re=0, Im=j) are implemented using four respective sets of independent loop filter stages 201 a - 201 d, the outputs of which are interleaved in time by switch (“SW”) 202 into the main noise shaping loop 209 discussed below. Each set of independent filter stages 201 a - 201 d, shown in further detail in FIG. 2D, includes a pair of filter stages 203 a and 203 b, corresponding feedforward stages 204 a and 204 b with coefficients C 1 and C 2 for setting the local poles, and a feedback loop 205 (with one delay Z −1 and gain g 1 ) and summer 206 for setting the local zeros. (The structure of each independent filter stage 201 a - 201 d may vary from a single filter stage 203 to three or more filter stages 203 and include more than one feedback loop, depending on the desired number and location of the local poles and zeros). The outputs from gain stages 204 a - 204 b of independent loop filter stage 201 a - 201 d are interleaved by a corresponding set of switches (SW) 207 a - 207 b into the modulator output summer 208 .
The global (baseband) noise shaping about DC ((direct current or zero frequency) (z-plane point Re=0, Im=0) is characterized by a fifth ( 5 th) order, main (shared) noise shaping loop 209 . Main noise shaping loop 209 is shown in further detail in FIG. 2 E and includes five (5) global filter stages 210 a - 210 e and associated feedforward stages 211 a - 211 e with respective coefficients C 3 -C 7 feeding-forward into output summer 208 (see FIG. 2 C). (The number of global filter stages 210 a - 210 e may also vary from embodiment to embodiment depending on the desired number and locations of the global pole—zero pairs in the NTF.) Feedback loops 212 a - 212 b (including a gain of g2 and a delay Z −1 ) and summers 213 a - 213 b are shown for moving the global noise shaping zeros on the z-plane unit circuit away from the DC point (Re=1, Im=0).
While the energy of each PWM stage 105 a to 105 N generally tracks the input energy over time (e.g., the first integral of the output energy tracks the first integral of the input energy), apparent distortion in the PWM output occurs because the moments of the PWM output energy vary with different PWM patterns (e.g., the values of the second and higher order integrals of the PWM output energy do not track the values of the higher order integrals of the input energy). In particular, the location of the second or higher moment for a given PWM output pattern depends on the specific digital word being converted and the corresponding number of logic high and logic low slots in the pattern, as well as the distribution of those slots across the time period of the pattern. The distribution of the slots in each pattern is affected, for example, by the technique used to generate that pattern (e.g., grow right, grow left, etc.).
In delta-sigma modulator 102 of FIG. 2C, a feed back compensation block 220 is included at the output of quantizer 214 to provide nonlinear feedback to the integrator stages 203 a - 203 b of second order loop filters 201 (see FIG. 2D) and/or integrator stages 210 a - 210 e of fifth order loop filter 209 (see FIG. 2 E). The nonlinear feedback provided by feedback compensation block 220 is described in incorporated U.S. Pat. Nos. 6,150,969 and 5,815,102, which were earlier cited and incorporated by reference. Generally, correction factors are fed back from feedback compensation block 220 to integrator stages 203 a - 203 b and 210 a - 210 b of delta-sigma modulator loop filters 201 a to 201 d and 209 . By selectively correcting the inputs to the corresponding integrator stages, the moments of the data into the inputs of the following PWM stages 105 a to 105 N are varied. In turn, the moments of the PWM outputs are corrected to reduce distortion, which would otherwise result from time varying output energy moments. For example, to correct for variations in the second moment in a given PWM output pattern, nonlinear correction factors are fed back to at least the second integration stages of the delta-sigma modulator loop filters 201 a to 201 d and 209 .
Returning to FIG. 2C, a single-bit quantizer 214 and a delay element (Z −1 ) 215 preferably generate the output of modulator 200 . The resulting output signal is fed-back to the inverting input of the modulator-input summer 216 to close the delta-sigma loop. By interleaving between independent sets of filter stages 201 a - 201 d, each set of filter stages 201 a - 201 d is contributing to the input of summer 208 at one-quarter (¼) of the sampling rate fs at the modulator input. Consequently, the poles and zeros set by filter sets 201 a - 201 d are translated to the z-plane points shown in FIG. 2 B.
Continuing with the by-four interleaved (N=4) embodiment of data converter 100 of FIG. 1, the four 32fs quantized sample streams output from interleaving circuitry 103 are respectively passed to four PWM stages 104 a to 104 N. In this example, each PWM stage 104 a to 104 N performs an eight-times (8×) oversampling from a 256fs oversampling clock signal (i.e. M=8). The resulting PWM encoded output pulse streams overlap in time, as shown in FIG. 3 .
FIG. 3 is a timing diagram depicting the conversion of an arbitrarily selected number of one-bit quantized samples output from noise shaper 102 at the 128fs oversampling frequency into multiple PWM streams at the 256 fs oversampling frequency. In FIG. 3, eight representative bits or samples (1-8) from the output of noise shaper 102 are shown by the trace labeled NSOUT. After a by-four interleave each PWM stage 104 a to 104 N operates on a new operand (sample) at the 32fs rate as respectively shown by the overlapping streams labeled PWM 1 , PWM 2 , PWM 3 , and PWM 4 .
For an eight-times oversampling, each PWM stage 104 a to 104 N encodes each corresponding sample received at the 32fs oversampling frequency into PWM encoded pulses, which are eight (8) periods of the 256fs oversampling clock signal, as represented by the streams labeled PWM 1OUT , PWM 2OUT , PWM 3OUT , and PWM 40UT in FIG. 3 . For example, the PWM 1OUT stream represents the output samples 1 and 5 of the noise shaper 102 , after by-four interleaving by interleaving circuitry 103 and eight-times oversampling by the corresponding PWM stages 104 a to 104 N, as PWM modulation periods (pulses) 1 - 1 through 1 - 8 and 5 - 1 to 5 - 8 .
The PWM encoded bitstreams PWM 1OUT , PWM 2OUT , PWM 3OUT , and PWM 4OUT are offset in time by two periods of the 256fs PWM oversampling clock (or equivalently one period of the 128fs noise shaper oversampling clock). Each of these time-overlapped streams modulates energy in the signal baseband of approximately 0 to fs/2 along with significant energy at the harmonics of the repeat frequency 32fs (e.g. 32fs, 64fs, 96fs, and so on) as shown in trace 401 of the output gain versus frequency plot of FIG. 4 . Consequently, each of the four PWM stages 104 a to 104 N is associated with an output FIR filter 105 a to 105 N with a response generally shown by trace 402 in FIG 4 . In particular, the response of each FIR filter 105 a to 105 N has notches about the harmonics of 32fs corresponding to the peaks in the output response of the corresponding PWM stage 104 a to 104 N at the same frequencies. FIR response 402 is achieved, for example, by using 16 stage boxcar FIR filters with simple coefficients.
In an embodiment with four digital-in, analog-out FIR filters 105 a to 105 N, each having a 16 stage boxcar filter, sixty-four analog outputs are provided into output summer 106 . The sixty-four analog outputs overlap in time and are matched in usage and transition rate (transition density). The result is a continuous-time, analog output with minimal noise and distortion due to ISI. Advantageously, the structure is such that all DAC elements have the same edge rate and same duty cycle of use. To a significant degree, this advantage causes the cancellation of all distortion and noise products.
The principles of the present invention are also embodied in the exemplary delta-sigma data converter 500 shown in FIG. 5 in which N number of delta-sigma modulators (noise shapers) 501 a - 501 N are interleaved in time and the resulting de-interleaved output streams are directly passed to output digital-in analog-out FIR filters 105 a to 105 N. In FIG. 5, L is the oversampling factor for each noise shaping stage 501 a - 501 N. The quantized data streams from noise shaping stages 501 a - 501 N are converted in FIR filters 105 a , . . . ,N at a frequency greater than or equal to the oversampling frequency L·(K/N)fs of noise shapers 501 a - 501 N. Advantageously, the DAC elements of FIR filters 105 a , . . . ,N are therefore matched in duty-cycle (usage) and transition rate as previously described.
Although the invention has been described with reference to specific embodiments, these descriptions are not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.
It is therefore, contemplated that the claims will cover any such modifications or embodiments that fall within the true scope of the invention. | A digital to analog converter including a noise shaping modulator for modulating an input digital data stream, a plurality of output elements for generating a plurality of intermediate data streams from a modulated output stream from the modulator, and an output summer for summing the intermediate data streams to generate an output analog stream. The noise shaping modulator balances an edge transition rate of the output elements, such that the edge transition rate of two selected elements is approximately equal. | 7 |
FIELD OF THE INVENTION
[0001] The invention relates to building structures, and more particularly to trim members for protecting, covering and decorating the area from the base of the roof to the upper portion of the outer wall of a building structure, such as a home or office or other commercial building, where the trim members are manufactured by pultrusion.
BACKGROUND OF THE INVENTION
[0002] In the United States, most residential or light weight-building systems employ wood or metal rafters, which extend from six to twenty-four inches beyond the outer wall. The outer wall is typically constructed of masonry or wood construction. Typically, the rafters and the sub-fascia (a member that connects the rafter ends together) support roof decking which forms the base of the roof. Shingles or other roofing materials cover the roof decking. Typically, the entire area from the lower edge of the roof decking to the upper portion of the outer wall of the building structure is covered with a cornice assembly, usually made of wood or wood covered with aluminum or vinyl. Aluminum or vinyl is a preferred material because of the high maintenance of wood trim pieces, which require repainting every few years (but in fact, vinyl cannot be painted at all). A fascia, usually the upper trim member of the cornice assembly, typically covers the sub-fascia or the outer portion of the rafter ends. This fascia protects the sub-fascia or rafter ends from the elements, and provides a decorative cover. The soffit, another trim member of the cornice, typically extends horizontally between the bottom inside edge of the fascia to the upper portion of the outer wall. The third trim member of the cornice assembly, known as the frieze, is a decorative member that starts at the soffit and runs down the outside surface of the top of the outer wall. The frieze is usually made of the same material as the fascia and soffit.
[0003] One problem associated with decorative and protective cornice assemblies is the labor required to install the several component parts, such as the fascia, the soffit, the frieze, and decorative moldings associated therewith. A second problem occurs when wood is used, which may rot and which requires regular repainting. A third problem is denting of aluminum products, and a fourth problem is expanding and contracting of aluminum and vinyl. Numerous fastening means, such as nails, staples, and the like must be used to attach the component parts together and/or to the building. This practice adds significant time and expense to the construction of a conventional building structure.
[0004] In addition, a problem associated with aluminum or vinyl cornice assemblies is the shearing of the fasteners used to fasten the cornice assembly or the enlarging of the holes created for fastening the assembly to the building structure. This shearing/enlarging problem is due to the relatively large amount of expansion and contraction due to temperature or moisture variations, which also causes buckling of the aluminum or vinyl material. As a result, the cornice assembly may become detached from the building structure or may appear warped.
[0005] In the past, a cornice assembly has had to be fabricated in place. Each portion of the cornice assembly is attached to the building individually. When a wood backing is used in conjunction with vinyl or aluminum assembly, yet another aspect of the assembly must be attached individually. This process is time-consuming, labor-intensive, and difficult to attain professional looking results.
[0006] A known method of manufacturing articles which have a lineal profile and a constant cross-section is called pultrusion. Pultrusion is the opposite of extrusion. It is a continuous pulling process in which rovings or strands of fibers are impregnated with resin and are then pulled through a heated die which cures the resin while also providing the cross-sectional shape to the piece. The cured piece is cut to length as it comes off the line. See, for example, “Pultrusion for Engineers” (Trevor F. Starr ed., CRC Press, 2000), which is hereby incorporated by reference. Pultruded material can be colored during manufacture, but unlike vinyl, also has surface that can accept and permanently retain paint.
[0007] Therefore, pultrusion is desirable to provide an improved method for the manufacture of the cornice assembly (or other trim members used in home construction), to protect the interface between the roof decking and the upper portion of the outer wall of a building structure. Pultrusion would provide a cornice assembly that minimizes structural instability by eliminating expansion and contraction of the cornice assembly and minimizes the use of fasteners while providing a less labor-intensive fabrication process. In addition, a pultruded cornice assembly is desirable to reduce production and labor costs, including the elimination of the need to paint the trim after assembly—although painting remains an option if color change is desired.
SUMMARY OF THE INVENTION
[0008] The present invention includes improved methods for fabricating cornice assemblies and other trim members used in house construction. The cornice assemblies and trim members are fabricated through a process of pultrusion. Improved cornice assemblies are disclosed, which include at least a fascia, a soffit and a frieze with crown molding, all of which may be integrated into a unitary structure. The improved cornice assemblies may be constructed from one, two or more trim members. Also disclosed is a method of trimming a building structure using the cornice assemblies and trim members made by pultrusion. The dies utilized in the pultrusion of the cornice assemblies and trim members are also disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a cross-section of a cornice assembly made of a unitary construction which includes a facia, a soffit, a crown, a frieze and a gutter.
[0010] FIG. 2 is a cross-section of a cornice assembly made of two trim members.
[0011] FIG. 3 is a pultrusion die with a channel for a unitary construction cornice assembly with a facia, a soffit, a crown, a frieze and a gutter.
[0012] FIG. 4 is a pultrusion die for a trim member including a soffit and a crown.
[0013] FIG. 5 is a pultrusion die for a trim member including a facia and a gutter.
[0014] FIG. 6 is a pultrusion die for a trim member including a frieze.
[0015] FIG. 7 is a cross-section of a cornice assembly made of three trim members.
[0016] FIG. 8 is a cross-section of a cornice assembly made of two trim members.
[0017] FIG. 9 is a cross-section of a trim member including a facia, a soffit and a gutter and a longitudinal section of the soffit including an area of vent holes.
[0018] FIG. 10 is a cross-section of a trim member including a facia and a soffit without gutter.
[0019] FIG. 11 is a cross-section of a trim member including a crown and a frieze where the frieze includes a slotted opening to receive wood, metal or vinyl siding.
[0020] FIG. 12 is a cross-section of a trim member including a crown and a frieze where the frieze includes a slotted opening to receive brick veneer.
[0021] FIG. 13A is a cross-section of a outside edge cap trim member.
[0022] FIG. 13B is a cross section of an inside edge cap.
[0023] FIG. 14 is a cross-section of a belt board trim member.
[0024] FIG. 15 is a cross-section of a rake trim member.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0025] Referring now to FIG. 1 , a cornice assembly 10 according to the invention is shown. The cornice assembly 10 includes portions a facia 12 , a soffit 14 , a crown 16 , and a frieze 18 . Optionally, the cornice assembly may also include a gutter 20 in which case the facia 12 forms the back side of the gutter 20 .
[0026] A significant advantage may be gained through a unitary construction (formed as one piece) of the cornice assembly 10 in terms of the amount of labor needed to install the cornice assembly 10 . With a unitary construction, effort need only be spent on attaching the cornice assembly 10 to the building structure, while effort spent on fabricating the cornice assembly 10 is completely eliminated.
[0027] The cornice assembly 10 may be used in with walls made of any suitable outer sheathing building material known in the art, such as plywood, fiber board, celotex, OSB (oriented strand board) and the like.
[0028] In a second embodiment, as best seen in FIG. 2 , the cornice assembly 22 may be made of two or more trim members which are connected together to form the overall cornice assembly 22 . For example, one trim member may comprise the gutter 20 , the facia 12 and the soffit 14 , while another trim member includes the crown 16 and the frieze 18 . In this embodiment, the trim members are preferably constructed such that they may be press fit together. However, any suitable means of connecting the trim members to form the cornice assembly 22 may be used, including adhesives, bolts, nails or screws. By using press fit connections, the effort of fabricating the cornice assembly 22 on the job site is reduced as compared to traditional cornice assemblies. First, trim members capable of being press fit can be connected without the use of tools. Second, because press fitting connections are separate from the means for attaching the cornice assembly 22 to the building structure, the cornice assembly 22 can be fabricated at ground level as opposed to during attachment to the building structure. This saves both on the effort needed to fabricate the cornice assembly 22 and to attach the cornice assembly 22 to the building structure.
[0029] The cornice assemblies and trim members of the present invention are preferably manufactured through the process of pultrusion. Pultrusion is an economical technique which is especially suited for the manufacture of cornice assemblies and other trim members because they have uniform cross-sections and also benefit from the high strength to weight ratio provided by pultrusion.
[0030] Of importance to the pultrusion process is the die through which the resin impregnated reinforcements are pulled. Die include multiple metal blocks, which, when assembled, has a through-hole or channel in the shape of the desired cross-section of the trim member. FIG. 3 shows a die 24 with a channel 25 which would be used to manufacture an entire cornice assembly in a unitary construction. As can be seen, a total of ten different blocks 26 - 44 make up the die 24 for the unitary construction of the cornice assembly. The various blocks of the die 24 are held together with bolts, screws or other suitable fasteners 46 . FIG. 4 shows a die 48 which is used to manufacture a portion of a cornice assembly including a soffit 14 and a crown 16 . The soffit/crown trim member made with die 48 would be connected to a trim member including a gutter 20 and a facia 12 made with die 50 , shown in FIG. 5 , and to a trim member including a frieze 18 made with die 52 , shown in FIG. 6 . Together the trim members created by these die 48 , 50 and 52 would fit together to form a cornice assembly 54 , shown in FIG. 7 .
[0031] Selection of the particular resin and reinforcements that may be used in the pultrusion of cornice assemblies and trim members are well within the design capability of those skilled in the art. Exemplary reinforcements include continuous strands of fiberglass, aramid fibers, and graphite. In addition, chopped strand, continuous strand or swirl mats may also be used as reinforcements. A useful reinforcement is glass fiber because it is economically priced as compared to other fibers, such as carbon fibers, and has a high strength to weight ratio. Exemplary resin include polyurethane, polyesters, vinyl esters, epoxy resins, acrylic and phenolic resins.
[0032] One or more stiffening ribs may be attached to the building structure side of the cornice assemblies and trim members. In FIG. 8 , stiffening rib 55 included in a two piece cornice assembly made of a trim member with a gutter 20 , a facia 12 and a soffit 14 and a trim member with a crown 16 and a frieze 18 . These stiffening ribs may be pultruded from the same die as the cornice assemblies or trim members. The stiffening ribs provide extra support for the cornice assemblies and trim members against forces applied there against. This bracing prevents damage which may result from the placement of ladders against the cornice assemblies and trim members, particularly placement of ladders at the frieze 18 . Furthermore, nailers 57 , 61 , which form a nailing surface for nailing the cornice assembly or trim member to the building structure.
[0033] The available cross-sections for trim members is unlimited. Exemplary cross-sections, in addition to the ones previously shown with regard to the die 48 - 52 , include a trim member 56 which includes a gutter 20 , a facia 12 and a soffit 14 shown in FIG. 9 , a trim member 58 which includes a facia 12 and a soffit 14 shown in FIG. 10 , a trim member 60 which includes a crown 16 and a frieze 18 (adapted for use with exterior sheet siding) shown in FIG. 11 . shown in FIG. 12 . The friezes shown in FIGS. 8 and 11 show a relatively narrow channel 63 for accepting exterior sheet siding (such as aluminum, vinyl, wood, or the like). The frieze shown in FIG. 12 has a relatively wide channel 65 designed to accept brick or stone veneering. The trim members 56 - 62 may be mixed and matched to achieve the desired cornice assembly.
[0034] Other trim members which may be pultruded include caps for covering vertical edges, as shown in FIG. 13A , which are used to cover an outside edge cap where two pieces of siding come together. Belt boards as shown in FIG. 14 , which are used to transition from one siding material 71 to another FIG. 13B shows an inside edge cap. One trim member which may be pultruded is a rake, which is used along the gable side of the intersection between the siding material 71 and the roof deck 73 , as seen in FIG. 15 .
[0035] One or more vent holes may be made in the soffit allow circulation of air and escape of moisture. These vent holes may be made shortly after the time of fabrication of the pultruded member or at the job site, as dictated by the needs of the installer. Vent holes 64 in the soffit 14 , are shown in a longitudinal view of the soffit portion 14 of trim member 56 in FIG. 9 .
[0036] Preferably, the method of attaching the trim members to each other are press fit connections 59 , as best seen in FIG. 11 , because such fasteners are easily constructed during the pultrusion process. However, because of the thermal stability of pultruded members, any fastening means may be used without concern about the expansion and contraction due to variations in temperature or moisture. Cornice assemblies and trim member manufactured via pultrusion expand and contract less than 1/26 th of that of steel over a given temperature range. Thus, fasteners will not be sheared by pultruded cornice assemblies and trim members.
[0037] Various fastening slots are needed in aluminum and vinyl siding trim members to facilitate expansion and contraction that occurs after installation around the fastening nail after installation. However, such fastening slots are not necessary with pultruded members because, as discussed above, the pultruded cornice assemblies and trim members of the present invention do not expand or contract due to changes in temperature or moisture. Thus, when fastening pultruded cornice assemblies to building structures, the step of having to form slots can be eliminated. Also, trim members made from aluminum or vinyl and more difficult to install than pultruded members because they cannot be firmly nailed to the sheathing but must be loosely nailed so that they literally “hang” from the mounting nails by way of the slots. Pultruded members can be nailed firm just like wood can be nailed to other wood.
[0038] Because the pultruded cornice assemblies and trim members of the present invention have superior rigidity and strength to weight ratios, a significantly fewer fasteners are needed to attach the cornice assemblies and trim members to building structures.
[0039] In combination with the pultruded cornice assemblies of the present invention and other trim members, a variety of butt joint caps, corner caps, and end caps may be used to complete the trimming of a building structure. Butt joint caps are used to bridge the area where two linear sections of a cornice assembly or trim member come together.
[0040] Corner caps are used to bridge the area where two linear section of a cornice assembly or trim members come together at a corner. Both inside and outside corners are needed. While not suitable for manufacturing by pultrusion, butt joint, end, and corner caps may cost effectively be manufactured by other conventional methods such as foam injection, plastic injection, urethane casting, and the like. Caps are preferably attached with two-sided tape.
[0041] End caps are used to close off the ends of cornice assemblies and trim members to prevent dirt and water from penetrating behind the cornice assembly and potentially damaging the building structure.
[0042] While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit. | The present invention is an improved method of making cornice assemblies and other trim members utilizing the process of pultrusion. The cornice assemblies and the other trim members made by the method of the present invention exhibit superior strength to weight ratios, low expansion and contraction due to changes in temperature and humidity, as well being less labor intensive to install. | 4 |
This application is a continuation of application Ser. No. 08/131,875, filed Oct. 5, 1993, now abandoned which is a continuation of application Ser. No. 07/721,534, filed as PCT/JP90/01467, Nov. 13, 1989 published as WO91/07533, May 30, 1991, now abandoned.
FIELD OF THE INVENTION
The present invention relates to an improvement on an ornamental tape or ribbon used in packaging.
DESCRIPTION OF THE PRIOR ART
Heretofore, it has been known to provide conventional ornamental tape or ribbon used in packaging, which ribbon is made of synthetic resin and is produced as follows: in a first step, a resilient sheet material of the synthetic resin is blanked with a suitable die to produce a tape blank having a plurality of spindle-shaped tape portions and a plurality of neck portions through each of which the spindle-shaped tape portions are integrally connected with each other; in a second step, a hole is formed in each of the neck portions of the tape blank to permit an end of a string to pass through every one of these holes, in sequence, so that the end of the string is fixed to the last one of the holes; and in a third step, the other or free end of the string is pulled to cause each of the spindle-shaped tape portions of the tape blank to be folded in half in sequence so as to, in sequence, assume a bow-tie form, a plurality of which bow-tie forms are then stacked together, whereby the conventional ornamental tape or ribbon used packaging is produced.
The conventional ornamental tape or ribbon having the above construction is characterized in that the tape blank is folded by the pulling of the string, through which pulling the thus folded tape blank assumes the form of stacked bow-ties. As is clear from the above, the conventional ribbon is complex in construction since it is constructed of a plurality of parts, i.e., the tape blank and the string passing through the blank. In addition, as for the assembling operation thereof, it is very cumbersome to perform the above second step for passing the string through the holes formed in the neck portions of the tape blank. Further, in some cases, there is a fear that the string impairs the handling properties of the ribbon in use.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an ornamental tape or ribbon used in packaging, which ribbon is very simple in construction while formed into a completed bow-tie shape through a single folding operation of a tape blank of the ribbon, the ribbon of the present invention being excellent in design, and, therefore excellent in the ornamental effect thereof.
The above object of the present invention is accomplished by providing:
An ornamental tape or ribbon comprising:
a base portion;
a predetermined number of spindle-shaped tape portions which are integrally formed with the base portion so as to laterally extend therefrom, the spindle-shaped tape portions being foldable;
at least a pair of suspended tape portions which are integrally formed with the base portion so as to vertically extend therefrom; and a fastening tape portion which is integrally formed with the base portion so as to vertically extend therefrom, the fastening tape portion being folded to pass through the base portion from its front side to a rear side of the same, so that the spindle-shaped tape portions having been folded is fastened to the base portion by the thus folded fastening tape portion.
In the ornamental tape or ribbon of the present invention, the spindle-shaped tape portions of the ribbon may be formed in only one side of the base portion of the ribbon, or formed in opposite sides of the base portion.
Further, the fastening tape portion of the ribbon of the present invention may be formed in the same side of the base portion as for the suspended tape portions of the ribbon, or formed in the other side of the base portion different from the side (of the base portion) in which the suspended tape portions are formed.
In the ribbon of the present invention, the fastening tape portion thereof may be fastened to the base portion of the ribbon through any desirable fastening means which may be a slot formed in a suitable area of the base portion or of each of the spindle-shaped tape portions of the ribbon.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a first embodiment of the ornamental tape or ribbon of the present invention;
FIG. 2 is a perspective view of the ribbon of the present invention shown in FIG. 1, having been partially folded;
FIG. 3 is a perspective view of the ribbon of the present invention shown in FIG. 1, having been entirely folded;
FIG. 4 is a perspective view of a modification of the first embodiment of the ribbon of the present invention shown in FIG. 1, having been partially folded, the modification being different in folding manner from the first embodiment shown in FIGS. 1 to 3;
FIG. 5 is a pattern view of a second embodiment of the ribbon of the present invention;
FIG. 6 is a perspective view of the folded or completed ornamental tape or ribbon of the embodiment shown in FIG. 5;
FIG. 7 is a pattern view of a third embodiment of the ribbon of the present invention;
FIG. 8 is a perspective view of the folded or completed ribbon of the embodiment shown in FIG. 7;
FIG. 9 is a pattern view of a modification of the third embodiment of the ribbon of the present invention shown in FIGS. 7 and 8;
FIG. 10 is a perspective view of the modification of the third embodiment of the present invention shown in FIGS. 7 and 8;
FIG. 11 is a pattern view of a fourth embodiment of the present invention;
FIG. 12 is a pattern view of a fifth embodiment of the present invention; and
FIG. 13 is a pattern view of a sixth embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described in detail with reference to the accompanying drawings.
FIGS. 1 to 4 show a first embodiment of the present invention. In the drawings, the reference character "A" denotes an ornamental tape of ribbon of the present invention. The ribbon "A" of the first embodiment of the present invention is made of ethylene-vinyl acetate (EVA) resin. More particularly, a laminated color sheet of the EVA resin is blanked with a suitable die to produce the ribbon "A" opposite sides of which is colored. The ribbon "A" is provided with: a central base portion 1; a pair of spindle-shaped tape portions 2 which are integrally formed with the base portion 1 so as to laterally extend from a side of the base portion 1 in series-as shown in FIG. 1, the spindle-shaped tape portions 2 being foldable; a pair of suspended tape portions 3 which are integrally formed with the base portion 1 so as to vertically extend from a lower side of the base portion 1; and a fastening tape portion 4 which is integrally formed with the base portion 1 so as to vertically extend from an upper side of the base portion 1, the fastening tape portion 4 being foldable.
Of the spindle-shaped tape portions 2 of the ribbon "A", an outer one 2 is provided with a tab 2a in its end portion. In addition, the fastening tape portion 4 is also provided with a tab 4a in its end portion. The tabs 2a and 4a are integrally formed with the outer spindle-shaped tape portion 2 and the fastening tape portion 4, respectively.
On the other hand, a slot 2b is formed in a neck portion 2b' disposed between the spindle-shaped tape portions 2 of the ribbon "A". Another slot la is formed in a substantially central area of the base portion 1 of the ribbon "A". Further, a slit 1b is formed in a branch area between the base portion 1 and the suspended tape portions 3, as shown in FIG. 1.
The ornamental tape of ribbon "A" of the present invention has the above construction. A pattern of the ribbon "A" is shown in FIG. 1, which pattern is folded into a shape shown in FIG. 3. Namely, in folding of the pattern, as shown in FIG. 2, first of all, each of the spindle-shaped tape portions 2 of the ribbon "A" is folded in half in sequence. Then, the tab 2a of the outer one of the spindle-shaped tape portions 2 is inserted into the slot 2b, in neck portion 2b; to prevent each of the spindle-shaped tape portions 2 from returning its flat condition under the influence of resiliency of the pattern or ribbon "A", so that the thus folded spindle-shaped tape portions 2 of the ribbon "A" is temporarily engaged with the base portion 1 of the ribbon "A". After that, the fastening tape portion 4 of the ribbon "A" is folded in half to have its tab 4a pass through the slit 1b from a front surface of the base portion 1 to a rear surface thereof and the tab 4a is engaged with the slit 1b, whereby each of the spindle-shaped tape portions 2 having been folded in half in front of the base portion 1 is fastened to the base portion 1 by the fastening tape portion 4. As a result, the pattern of the ribbon "A" shown in FIG, 1 is formed into a bow-tie shape as shown in FIG. 3.
In case that the pattern of the ribbon "A" has its front surface assume a color different from that of the rear surface of the pattern, the folded or completed ribbon "A" of the present invention may show a rich variety of color, as shown by striped and plain surfaces in FIGS. 2 and 3.
In addition, when the spindle-shaped tape portions 2 of the pattern of the first embodiment of the ribbon "A" shown in FIG. 1 are folded in another way different from that shown in FIG. 2, a modification of the first embodiment of the ribbon "A" is completed as shown in FIG. 4. More specifically, as shown in FIG. 4, in the folding operation of this modification: in a first step, the spindle-shaped tape portions 2 are folded, in a first direction, outwardly and over base portion 1 with neck portion 2b' overlaying base portion 1, the outermost portion 2 is folded outwardly and back in a direction opposite to the first direction and the tab 2a, at the outer end of outermost tape portion 2, is twisted and inserted into the slot 1a of the base portion 1 so that the spindle-shaped tape portions 2 are folded so as to be symmetrically arranged with respect to the base portion 1; and, in a second or last step, the tab 4a of the fastening tape portion 4 is engaged with the slit 1b of the ribbon "A" in the same way as that of the first embodiment of the present invention shown in FIG. 3, so that the ribbon "A" of the modification shown in FIG. 4 is tied in a bow. As is clear from FIG. 4, the completed ribbon "A" of the modification shown in FIG. 4 partially differs in color (of the spindle-shaped tape portions 2) from that of the first embodiment of the present invention shown in FIG. 3, so that the modification of the present invention shown in FIG. 4 may make a variety of color of the ribbon "A" richer.
FIGS. 5 and 6 show a second embodiment of the ribbon "A" of the present invention. In the drawings, like reference numerals apply to similar parts throughout the several views.
In this second embodiment of the present invention, there are employed four pieces of the spindle-shaped tape portions 2 two of which are adjacent to the base portion 1 in series and are larger in length and width than the remaining tape portions 2. As a result, when the spindle-shaped tape portions 2 of the second embodiment of the present invention are folded as shown in FIG. 6, a double bow-tie is formed on the base portion 1 of the ribbon "A". Incidentally, in the pattern of the ribbon "A" shown in FIG. 5, each of holes 2c formed in neck portions of the pattern between the spindle-shaped tape portions 2 is a mark for indicating a folding area of the pattern being folded. It is possible to eliminate these marks or holes 2c from the pattern of the ribbon "A" shown in FIG. 5.
FIGS. 7 and 8 show a third embodiment of the ribbon "A" of the present invention, in which embodiment the spindle-shaped tape portion 2 is integrally formed with the base portion 1 so as to laterally extend from each of opposite sides of the base portion 1. The pattern of the third embodiment of the present invention is folded in a manner shown in FIG. 8 to form an essential bow-tie part of the ribbon "A".
FIGS. 9 and 10 show a modification of the third embodiment of the present invention shown in FIGS. 7 and 8, in which modification a hook 2d is integrally formed with an outer end of each of the spindle-shaped tape portions 2 which are symmetrically arranged with respect to the base portion 1. In folding operation of the pattern of the modification of the ribbon "A" shown in FIG. 9: in a first step, each of the spindle-shaped tape portions 2 is folded in half to permit the hooks 2d of the spindle-shaped tape portions 2 to engage with each other; and, in a second or last step, the fastening tape portion 4 is folded in half to have its hook 4a engaged with the slit 1b of the ribbon "A" so that the ribbon "A" is tied in a bow, as is in each of the above embodiments and modification of the present invention.
In each of the above embodiments and modification of the first embodiment of the present invention, the tabs 2a and 4a are engaged with the slot 1a and the slit 1b, respectively. However, it is also possible to fasten the ends of the spindle-shaped tape portions 2 to the base portion 1 by the use of suitable fastening means such as heat sealing means, gluing means, mechanical fastening means such as staplers and like fastening means.
FIGS. 11, 12 and 13 show a fourth, fifth and sixth embodiments of the ribbon "A" of the present invention, respectively, in each of which embodiments the fastening tape portion 4 is so integrally formed with the base portion 1 as to vertically extend from the lower side of the base portion 1. More specifically, in each of the embodiments of the present invention shown in FIGS. 11 to 13, the fastening tape portion 4 is provided between the suspended tape portions 3 and extends downward as is in case of the suspended tape portions 3.
In the fourth embodiment of the present invention shown in FIG. 11, as a means for fastening the fastening tape portion 4 to the base portion 1, there is employed a thin slot 5 in the base portion 1 for receiving a mushroom-like end of the fastening tape portion 4 therein. On the other hand, in the fifth embodiment of the present invention shown in FIG. 12, as a means for fastening the fastening tape portion 4 to the base portion 1, there is employed a T-shaped slit 6 in an upper area of the base portion 1 for receiving a mushroom-like end of the fastening tape portion 4 therein. In the sixth embodiment of the present invention shown in FIG. 13, as a means for fastening the fastening tape portion 4 to the base portion 1, there is employed a notch 7 in a neck portion between the spindle-shaped tape portions 2, which notch 7 receives a mushroom-like end of the fastening tape portion 4 therein.
Each of the thin slot 5, T-shaped slit 6 and the notch 7 described above is used to fasten the mushroom-like end of the fastening tape portion 4 to the base portion 1 of the ribbon "A" in folding operation of the pattern of each of the embodiments shown in FIGS. 11 to 13.
As for the industrial applicability of the present invention, as described in the above, according to the present invention, it is possible to provide the ornamental tape or ribbon used in packaging, which ribbon is simple in construction and excellent in design, and, therefore excellent in ornamental effect, the ribbon of the present invention being easily formed or completed by only folding the pattern of the ribbon. Incidentally, the ornamental tape or ribbon of the present invention having been completed is bonded in use to an article (to be ornamented therewith) by means of a suitable bonding means, for example such as double-faced adhesive tapes, adhesive agents and the like. | An ornamental tape or ribbon having a base portion; a plurality of spindle-shaped tape portions extending from at least one side of the base portion; a plurality of suspended tape portions vertically extending from one of an upper and a lower side of the base portion; and a fastening tape portion vertically extending from another of an upper side and a lower side of the base portion across the base portion and having a tab for engagement in a slot where the vertically extending tape portions join the base portion. | 3 |
CLAIM OF BENEFIT OF PROVISIONAL APPLICATION
Pursuant to 35 U.S.C. §119, the benefit of priority from provisional application 60/161,113, with a filing date of Oct. 22, 1999, is claimed for this non-provisional application.
ORIGIN OF THE INVENTION
The invention described herein was made by an employee of the United States Government and a National Research Council Research Associate and may be used by or for the Government for governmental purposes without the payment of any royalties thereon or therefor.
CROSS REFERENCE TO RELATED CASES
This application is related to co-pending, commonly owned patent application Ser. No. 09/696,524, filed Oct. 23, 2000, entitled “Polymer-Polymer Bilayer Actuator”, co-pending commonly owned patent application Ser. No. 09/696,528, filed Oct. 23, 2000, entitled “Electrostrictive Graft Elastomers,” and co-pending, commonly owned patent application Ser. No. 09/696,527, filed Oct. 23, 2000, entitled “Membrane Position Control.”
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is generally related to the field of electroactive actuators. More specifically, it relates to an electroactive actuator having at least one layer of non-uniform thickness.
2. Description of the Related Art
Actuation devices are used for many applications, including aerospace, fluid flow and biomedical. Space applications include robotics, miniature rovers, and the shaping, tuning, positioning, controlling and deforming of membrane structures. Membrane inflatable and deployable space structures are used by the government and commercially as reflectors, antennas, solar arrays, satellites, solar sails, etc. Although actuation devices are widely used, many challenges exist which limit their performance for high precision applications. Factors affecting precision include surface smoothness, deviation from desired surface profile, surface deformations due to thermal fluctuations, and accurate membrane positioning. Additionally, hydrofoils and airfoils that can optimize their surface shape at varying flow rates are desirable to, for example, increase lift, reduce noise levels, lower vibrations and reduce drag. Other potential uses of actuation devices include precise positioning of display panels and optical index layers. To operate most effectively in the aforementioned applications, actuation devices require sufficient force and strain, and often need to produce complex motions that may include both bending and torsion.
Conventional piezoelectric ceramic, polymer, and composite actuators (including piezoelectric, electrostrictive, and electrostatic) lack the combination of sufficient strain and force to most effectively perform the aforementioned functions. Previous concepts for shaping and tuning membrane structures have primarily involved the use of piezoelectric ceramic materials. These ceramic piezoelectrics have the major problems of large mass, high density, low strain and high brittleness. Generally, piezoceramics also need additional mechanical devices to achieve a shaping, tuning, positioning, controlling or deforming function. In contrast to electroceramics, electroactive polymers are emerging as new actuation materials due to their enhanced strain capabilities.
Electrostrictive polymer-polymer actuators or other electroactive polymer actuators that provide enhanced strain capabilities can shape, tune, position, control and deform membrane structures, as well as perform in other applications, in ways not previously possible with other materials. An example of such an electrostrictive polymer-polymer actuator is described in the patent application entitled “Polymer-Polymer Bilayer Actuator”, Ser. No. 09/696,524, filed Oct. 23, 2000, hereby incorporated by reference. The greater strain capability provides further possibilities for small-scale applications and integration into skin surfaces. The electroactive actuators can coincide with specific contours to optimize, for example, shapes for fluid flow, reflection and other membrane uses.
Existing devices capable of providing complex motion response utilize surface electrode patterning and/or polymer laminates having tailored lamina properties and orientations, such as described in U.S. Pat. No. 4,868,447. It is desirable to obtain complex motion response without requiring tailored surface electroding or laminate design.
STATEMENT OF THE INVENTION
Accordingly, an object of the present invention is to provide an electroactive device having controlled local strain and curvature.
Another object is to provide an electroactive device having a response contour which varies across the device.
Another object is to provide an electroactive device that can produce complex motions.
A further object is to provide an electroactive device with enhanced strain capabilities.
Additional objects and advantages of the present invention are apparent from the drawings and specification that follow.
SUMMARY OF THE INVENTION
In accordance with the present invention, the foregoing and other objects and advantages are attained by providing an electroactive device having at least two layers of material, wherein at least one layer is an electroactive material and wherein at least one layer is of non-uniform thickness. The device can be produced in various sizes, ranging from large structural actuators to microscale or nanoscale devices. The applied voltage to the device in combination with the non-uniform thickness of at least one of the layers (electroactive and/or non-electroactive) controls the contour of the actuated device. The effective electrical field is a mathematical function (E=V/D, where E is electrical field, V is voltage and D is thickness) of the local layer thickness. Therefore, the local strain and the local bending/torsion curvature are also a mathematical function of the local thickness. Hence the thinnest portion of the actuator offers the largest bending and/or torsion response. Tailoring of the layer thicknesses can enable complex motions to be achieved.
In a preferred embodiment, one or more electroactive layers of non-uniform thickness control the curvature of the device. The most responsive portions of the device will be at the thinnest portions of the electroactive layers, where the highest electric fields result. In other embodiments, the curvature can be controlled by varying the thickness of the non-electroactive layer or by varying the thickness of both the electroactive layer(s) and non-electroactive layer.
The electroactive device described herein will provide enabling technology to allow variable contouring of the device to expand electroactive actuator use in applications such as motion control, position control, tension control, curvature control, biomedical pulse control, surface flow dynamic control, display panels, optical alignment, optical filters, micro-electromechanical systems, and nano-electromechanical systems. More specifically, it can be utilized in membrane inflatable and deployable structures, and be used for shaping surfaces such as hydrofoils and airfoils to optimize shape for different flow rates. Furthermore, the device could serve to provide precise positioning of an optical index layer for a liquid crystal display and provide positioning control of display panels to reduce glare.
Advantages of using polymers for the electroactive layer(s) include low weight, unified materials-device body, simple operation, long lifetime, flexibility, toughness, and ease of processing. However, use of layers (electroactive and/or non-electroactive) of non-uniform thickness to control the curvature can be applied to any materials that can cooperatively produce a sufficient force and strain combination for particular shaping, tuning, positioning, controlling and deforming applications.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention and the many of the attendant advantages thereof will be readily attained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
FIG. 1A illustrates a side view of an embodiment of a non-uniform thickness actuator, showing the most responsive portions located at the thinnest points of the active layer closer to the free end.
FIG. 1B illustrates a side view of an embodiment of a non-uniform thickness actuator, showing the most responsive portions located at the thinnest points of the active layer closer to the cantilevered end.
FIG. 2 illustrates a side view of a non-uniform thickness actuator fixed at one end, with the thickness of the active layer decreasing towards the fixed ends.
FIGS. 3A–3C illustrate a cross section of a typical hydrofoil or airfoil with a non-uniform thickness actuator, in actuated and non-actuated configurations, attached to the surface of the foil.
FIG. 3D illustrates a cross section of a typical hydrofoil or airfoil with a non-uniform thickness actuator integrated into the foil.
FIG. 4 illustrates an embodiment of a non-uniform thickness actuator having stacked electroactive layers, wherein the stacks on either side of the bond interface are alternately activated.
FIG. 5 illustrates an embodiment of a non-uniform thickness actuator having multiple electroactive layers.
FIG. 6 illustrates thickness variation of a single layer of an actuator.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and more particularly to FIGS. 1A and 1B , an electroactive device according to the present invention is shown and referenced generally by the numeral 100 . Electroactive layer 112 is of non-uniform thickness and is bonded to non-electroactive layer 114 , which has uniform thickness. A layer should be understood to be a sheet, strip, film, plate, or the like, which may have various configurations such as planar, annular, and spiral. Although either or both layers can be of nonuniform thickness, nonuniformity of the electroactive layer thickness will produce the greatest strain, and hence displacement capability of the device. Electroactive layer 112 can be any material that responds to electrical activation, including a polymer, ceramic or composite, and is selected based upon the response desired. A preferred material is the electrostrictive graft elastomer described and claimed in “Electrostrictive Graft Elastomer”, Ser. No. 09/696,527, filed Oct. 23, 2000, hereby incorporated by reference. Another preferred embodiment is the polymer-polymer actuator described and claimed in “Polymer-Polymer Bilayer Actuator”, Ser. No. 09/696,524, filed Oct. 23, 2000, also hereby incorporated by reference, wherein the active polymeric web has non-uniform thickness. Non-electroactive layer 114 must have a mechanical modulus sufficient to obtain the desired response in conjunction with electroactive layer 112 . For equal thickness of the electroactive layer 112 and non-electroactive layer 114 , the mechanical modulus of the non-electroactive layer 114 is preferred to be equal to or lower than the mechanical modulus of the electroactive layer 112 in order to achieve maximum bending displacement. Candidate materials include polymers, ceramics, composites, and metals.
The layers 112 and 114 are bonded using chemical, physical, mechanical, or biological bonding means. The preferred bonding means provide ease in processing, minimized thickness, as well as the desired stiffness and durability. Especially preferred is a chemical adhesive that is cast and cured at room temperature. The bonding layer thickness depends on the whole configuration of the device, including the material selections for the electroactive and non-electroactive layers, as well as the device's displacement and stress induced at the bonding interfaces. The thinnest bonding layer that satisfies the device requirements is preferred. Epoxy resin is a suitable chemical adhesive.
Layers 112 and 114 are fixedly mounted at 116 and electrically connected to a drive voltage (not shown). When no voltage is supplied, the device remains in the non-activated position 120 . In FIG. 1A , when voltage is supplied, electrical signals are supplied across the thickness of layer 112 , and the electroactive response of layer 112 causes device 100 to bend to position 140 . The electrical signals are supplied via one or more electrodes 130 disposed on each of the upper and lower surfaces of layer 112 . These electrodes 130 can be disposed via a single layer across the surface or via multiple or patterned electrodes, depending on the desired response. One example of suitable electrodes 130 are gold electrodes, although any material having significant conductivity (generally greater than 10 5 S/m) and fatigue resistance can be used. A conductive polymer having mechanical elasticity comparable to the electroactive material and good adherence to the electroactive material is preferred for the electrode material. Some examples of suitable electrodes are polypyrrole and polyaniline. The drive voltage is dependent on the number of device layers, as well as on the desired displacement, and can range from several volts to several kV.
The most responsive area of device 100 is position 140 at the thinnest portion of electroactive layer 112 . Similarly, in FIG. 1B , the most responsive area of device 100 is position 150 , at the the thinnest portion of electroactive layer 112 . In other embodiments the non-electroactive layer 114 may be of non-uniform thickness, although lesser displacement of the device would be achieved.
The thickness ratio between electroactive layer 112 and non-electroactive layer 114 can be tailored to achieve the desired response. If the electroactive and non-electroactive layers have the same mechanical modulus, then the non-electroactive layer thickness should be less than or equal to that of the electroactive layer thickness. If the moduli differ, the thicknesses are optimized based on the application requirements. The thickness of the layers 112 and 114 depend upon the desired response. For multiple electroactive layers, the thicknesses of the layers, the moduli of the layers, and the material selection is tailored to achieve desired results.
Referring to FIGS. 2A and 2B , another embodiment of the electroactive device according to the present invention is shown and referenced generally by the numeral 200 . Electroactive layer 212 is narrowed at each end and is bonded along its length to non-electroactive layer 214 , which has uniform thickness. Device 200 is fixedly attached at 280 to a structure 235 on which the actuator acts. Furthermore, device 200 can be attached to the support layer 235 by chemical or mechanical means. Electroactive layer 212 is electrically connected to a drive voltage (not shown). When no voltage is supplied, as illustrated in FIG. 2A , the device 200 remains in its non-activated position. When voltage is supplied, as illustrated in FIG. 2B , the electroactive response of layer 212 causes device 200 to bend to its activated position. The most responsive areas of the device 200 are at the thinnest portions of layer 212 , nearest ends 280 and 290 .
FIGS. 3A through 3C depict an application in which a non-uniform electroactive device is used to optimize characteristics of a hydrofoil or airfoil. Such optimization may include the formation of traveling waves. Cross-Section 300 represents a typical airfoil or hydrofoil. One or more non-uniform thickness electroactive actuators 310 are affixed to the airfoil or hydrofoil, preferably at the leading edge. In the activated positions 320 and 330 , the actuators form a curvature that alters the flow stream 340 . FIG. 3B illustrates the actuator displacement resulting from the actuator being fixed at 350 to the airfoil or hydrofoil. FIG. 3C illustrates an actuator displacement resulting from the actuator being fixed at 360 to the airfoil or hydrofoil. In another embodiment, shown in FIG. 3D , one or more electroactive devices 370 are integrated into the airfoil or hydrofoil; i.e., attached to and recessed within the hydrofoil or airfoil 300 . Again, the electroactive devices are affixed at one end to the airfoil or hydrofoil. This embodiment results in a smooth airfoil/hydrofoil surface when the electroactive device(s) 370 are in their inactivated state.
FIG. 4 illustrates an embodiment having multiple electroactive layers 400 through 450 . Electroactive layers 400 through 420 form a first stack 470 and electroactive layers 430 through 450 form a second stack 480 . The first stack 470 and second stack 480 are bonded via bonding layer 460 . First stack 470 and second stack 480 are alternately activated. Although electroactive layers 400 through 450 can be different materials, consistent materials are preferred to obtain greater control of the device.
FIG. 5 illustrates an embodiment having three electroactive layers 510 through 530 and a single non-electroactive layer 500 . Such a multiple electroactive layer arrangement may be used to obtain greater output force and greater strain/displacement for a given drive voltage.
Referring now to FIG. 6 , the thickness variation of one or more layers is chosen to achieve a desired contour. The thickness of a layer can vary as any function of length (t=f(1)), any function of width (t=f(w)), or as any function of both length and width (t=f(1,w)). This thickness variation acts in cooperation with and/or enhances the contour that could be achieved by material choice, electrode design, or orientation of layers.
Although the drawings illustrate specific configurations, the invention is not limited to such specific configurations. At least one electroactive layer is required and at least one non-uniform thickness layer (electroactive or non-electroactive) is required, but each desired application and its associated desired response (strain and force) will dictate the number of electroactive layers and number of nonuniform layers needed. A non-electroactive layer is not required, such as the embodiment shown in FIG. 4 illustrates; however, if a non-electroactive layer is used, there should be no more than one. As provided earlier, such non-electroactive layer may be of uniform or non-uniform thickness depending on the desired results. Although the embodiments shown illustrate the electroactive devices being fixed at an end, they may be fixed to another location as desired for a specific application. For example, the electroactive device itself could be the membrane to be deformed, such as a reflector, and have a centrally fixed point.
Factors which affect the performance of the present invention include: 1) the non-uniformity in layer thicknesses; 2) electromechanical properties of the electroactive layer, such as electric field induced strain, mechanical modulus, and electromechanical conversion efficiency, as well as output energy/energy density; 3) mechanical properties of the non-electroactive layer, such as mechanical modulus; 4) bonding between the layers, as well as 5) the geometric dimension of each component. For an optimized configuration; 1) the electroactive layer(s) offer maximized electric field induced strain and maximized mechanical modulus, therefore, maximized electromechanical output power/energy; 2) the non-electroactive layer offers mechanical modulus not higher than that of the electroactive layer(s); 3) the bonding between layers offers strength, does not allow any significant sliding effect between the electroactive and non-electroactive layers in the direction parallel to the surfaces, and offers maximized durability under working conditions; 4) the relative dimensions of the electroactive layer(s) and non-electroactive layer are chosen according to the requirements of a particular application, with a relatively thin non-electroactive layer being preferred; 5) the thickness of the bonding material is minimized; and 6) the non-uniform thicknesses of layers are designed to meet desired response requirements.
Obviously, numerous additional modifications and variations of the present invention are possible in light of above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than is specifically described herein. | An electroactive device comprises at least two layers of material, wherein at least one layer is an electroactive material and wherein at least one layer is of non-uniform thickness. The device can be produced in various sizes, ranging from large structural actuators to microscale or nanoscale devices. The applied voltage to the device in combination with the non-uniform thickness of at least one of the layers (electroactive and/or non-electroactive) controls the contour of the actuated device. The effective electric field is a mathematical function of the local layer thickness. Therefore, the local strain and the local bending/torsion curvature are also a mathematical function of the local thickness. Hence the thinnest portion of the actuator offers the largest bending and/or torsion response. Tailoring of the layer thicknesses can enable complex motions to be achieved. | 7 |
FIELD
[0001] Embodiments herein relate to hydraulic fracturing including proppant placement.
BACKGROUND
[0002] A standard approach to optimization under uncertainty is based on original Markovitz portfolio theory and more recently was tailored to oilfield applications with modified definition of efficient frontier (U.S. Pat. No. 6,775,578 B. Couet, R. Burridge, D. Wilkinson, Optimization of Oil Well Production with Deference to Reservoir and Financial Uncertainty, 2004) and Value of Information (Raghuraman, B., Couët, B., Savundararaj, P., Bailey, W. J. and Wilkinson, D.: “Valuation of Technology and Information for Reservoir Risk Management,” paper SPE 86568, SPE Reservoir Engineering, 6, No. 5, October 2003, pp. 307-316). However, these methods employ mean-variance approach and do not provide a much needed insight into the inherent uncertainty of the optimized model and, more importantly, any quantitative guidance on reducing this uncertainty, which is very desirable from the operational point of view.
[0003] Application of Global Sensitivity Analysis to address various problems arising in oilfield industry has been described for reservoir performance evaluation, for measurement screening under uncertainty, for pressure transient test design and interpretation, for design and analysis of miscible fluid sampling clean-up, and for targeted survey design. However, these disclosures were focusing only on quantifying uncertainty in specific physical quantities and using that analysis to gain a new insight about the measurement program design and interpretation. The references did not look at optimization of the underlying physical processes.
BRIEF DESCRIPTION OF THE FIGURES
[0004] FIG. 1 is a workflow summarizing adaptive GSA-optimization approach.
[0005] FIG. 2 is a workflow summarizing the inputs and outputs for the example proppant placement and fracture conductivity calculation.
[0006] FIG. 3 is a schematic diagram providing a definition of cycle phase shift and perforation spacing for two injectors from a vertical well into a vertical fracture.
[0007] FIG. 4 is a schematic diagram illustrating the length of the cycle and length of the proppant-laden portion.
[0008] FIG. 5 is a schematic diagram for one example considered. The final placed distribution of proppant is also influenced by mixing between the proppant-laden and clean fracturing fluid portions. The mixing process is characterized by a single mixing length.
[0009] FIG. 6 is a workflow illustrating the inputs, outputs, and workflow for the example proppant placement and fracture conductivity calculation.
[0010] FIG. 7 is a chart plotting three points of the efficient frontier from the optimization using initial ranges for uncertain variables. Lower values of the objective function (μ−λσ) for increasing values of λ illustrate the inherent penalty for risk.
[0011] FIG. 8 is a chart plotting three points of the efficient frontier from the optimization using GSA-updated ranges for uncertain variables. Initial efficient frontier points are also included for comparison. Lower values of the objective function (μ−λσ) for increasing values of λ illustrate the inherent penalty for risk.
SUMMARY
[0012] Embodiments herein relate to apparatus and methods for delivering and placing proppant to a subterranean formation fracture including identifying control variables and uncertain parameters of the proppant delivery and placement, optimizing a performance metric of the proppant delivery and placement under uncertainty, calculating sensitivity indices and ranking parameters according to a relative contribution in total variance for an optimized control variable, and updating a probability distribution for parameters, repeating optimizing comprising the updated probability distribution, and evaluating a risk profile of the optimized performance metric using a processor. Some embodiments may deliver proppant to the fracture using updated optimized values of control variables.
DETAILED DESCRIPTION
[0013] This disclosed approach combines Global Sensitivity Analysis (Saltelli et al., 2004) with optimization under uncertainty in an adaptive workflow that results in guided uncertainty reduction of the optimized model predictions. Embodiments herein relate to a general area of optimization under uncertainty. The application of the disclosed method relates to well stimulation and hydraulic fracturing in particular. Heterogenous Proppant Placement (HPP) strategies seek to increase propped fracture conductivity by selectively placing the proppant such that the fracture is held open at discrete locations and the reservoir fluids can be transported through open channels between the proppant. Schlumberger Technology Corporation provides well services that include introducing proppant into the fractures in discrete slugs (Gillard, M. et al., 2010; Medvedev, A. et al., 2013). For the purposes of technology development and optimal implementation, tools must be developed for predicting the conductivity of the heterogeneously propped fractures during the increase in closure stress resulting from flow-back and subsequent production. In the presence of uncertainty in formation properties, optimal HPP strategies will result in inherently uncertain predictions of fracture conductivity. Herein, we describe a method to reduce uncertainty in predicted fracture conductivity and identify an optimal HPP operational strategy for an acceptable level of risk.
[0014] Embodiments herein show how a predictive physics-based HPP model is used to estimate fracture conductivity under a given closure stress. The input parameters of the model are divided into control variables (operational controls may include dirty pulse fraction, injector spacing, proppant Young's modulus etc.) and uncertain variables (uncertain formation properties may include Poison ratio, Young's modulus, proppant diffusion rates etc.). The model is first optimized to obtain values of control variables maximizing mean fracture conductivity (for a given closure stress) under initial uncertainty of formation properties. An efficient frontier may be obtained at this step to characterize dependence between the optimized mean value of fracture conductivity and its uncertainty expressed by the standard deviation. Global sensitivity analysis (GSA) is then applied to quantify and rank contributions from uncertain input parameters to the standard deviation of the optimized values of fracture conductivity. Uncertain parameters are ranked according to their calculated sensitivity indices and additional measurements can be performed to reduce uncertainty in the high-ranking parameters. Constrained optimization of the model with reduced ranges of uncertain parameters is performed and a new efficient frontier is obtained. In most cases, the points of the updated efficient frontier will shift to the left indicating a reduction in the risk associated with achieving the desired fracture conductivity. The disclosed method provides an adaptive GSA-optimization approach that results in uncertainty reduction for optimized HPP performance.
[0015] The workflow is applied for HPP optimization, which requires a capability for the prediction of the placement of proppant and the resultant conductivity within a potentially rough fracture under any prescribed closure stress. This capability receives inputs relating to the pumping schedule, proppant properties and formation properties and provides a prediction of the achieved fracture conductivity. For example, in our demonstration, we utilize the methods in U.S. Provisional Patent Application Ser. No. 61/870,901, filed Aug. 28, 2013 which is incorporated by reference herein in its entirety where the combination of fracture and proppant is represented by a collection of asperities arranged upon a regular grid attached to two deformable half-spaces. The deformation characteristics of the deformable half-spaces are pre-calculated, allowing for very efficient prediction of the deformation of the formation on either side of the fracture. The method automatically detects additional contact as the fracture closes during increasing closure stress (such as during flow-back and production). In addition, the asperity mechanical response is modified to account for the combined mechanical response of the rough fracture surface and any proppant that may be present in the fracture at that location. In this way, the deformation of any combination of fracture roughness and heterogeneous arrangement of proppant in the fracture can be evaluated. The deformed state is then converted into a pore network model which calculates the conductivity of the fracture during flow-back and subsequent production. Embodiments herein allow one to progressively reduce uncertainty in the performance of an optimized HPP operational strategy by iterative reduction of uncertainty in identified properties of the reservoir.
Optimization Under Uncertainty and Global Sensitivity Analysis
[0016] Let us consider a general case when the underlying physical process is modeled by a function y=f(α, β), where α={α 1 . . . α N } and β={β 1 . . . β M } are two sets of parameters. Here, α represents the set of control parameters (to be used in optimization), and β denotes the set of uncertain parameters. Mathematically, β's are considered to be random variables represented by a joint probability density function (pdf). Therefore, for each vector of control variables α, the output of the model is itself a random variable with its own pdf (due to uncertainty in β). A mean-variance approach is commonly used for optimization, i.e. a function of the form
[0000] F =μ(α,β)−λσ(α,β)
[0000] where μ, and σ are the mean and standard deviation of the output y of the numerical simulation, and λ is a non-negative parameter defining a tolerance to risk (uncertainty). The optimization problem can then be formulated as
[0000]
max
α
F
(
α
,
β
)
[0017] For each optimization iteration, a sample of the random vector β is chosen, and the values of y(α, β) are first computed using this sample for a given a and then averaged over β.
[0018] Various optimization algorithms can then be used to find the optimal value of α. The process of optimizing under uncertainty will lead to a set of parameters α opt that provide the optimum of the objective function F. Therefore, an optimized model is now available:
[0000] y=f (α opt ,β)
[0000] Note that the optimized model still has inherent uncertainty due to the uncertainty in parameters β.
[0019] A set of solutions to the optimization problem can be plotted in (μ, σ) coordinates, where optimal points corresponding to pre-defined values of λ will form an efficient frontier ( FIG. 7 ). This represents a risk profile of the underlying modeled process. The positive slope of the frontier illustrates the penalty for additional uncertainty (risk).
[0020] From the operational perspective, the goal is to reduce this risk while maintaining the same level of expected performance (represented by μ). In order to reduce the uncertainty, one needs to understand where it is coming from. Therefore, a quantitative link between uncertainties in input parameters (β) and uncertainty in the output is desirable. This link can be quantified using Global Sensitivity Analysis based on variance decomposition.
[0021] Global sensitivity analysis (Saltelli et al., 2004) based on variance decomposition is used to calculate and apportion the contributions to the variance of the measurement signal V(Y) from the uncertain input parameters {X i } of the subsurface model.
[0022] For independent {X i }, the Sobol' variance decomposition (Sobol', 1993) can be used to represent V(Y) as
[0000] V ( Y )=Σ i=1 N V i +Σ 1≦i<j≦N V ij + . . . +V 12 . . . N , (1)
[0000] where V i =V[E(Y|X i )] are the variance in conditional expectations (E) representing first-order contributions to the total variance V(Y) when X i is fixed i.e., V(X i )=0. Since we do not know the true value of X i a priori, we have to estimate the expected value of Y when X i is fixed anywhere within its possible range, while the rest of the input parameters {X ˜i } are varied according to their original probability distributions. Thus,
[0000] S 1 i =V i /V ( Y )
[0000] is an estimate of relative reduction in total variance of Y if the variance in X i is reduced to zero.
[0023] Similarly, V ij =V[E(Y|X i , X j )]−V i −V j is the second-order contribution to the total variance V(Y) due to interaction between X i and X j . Notice, that the estimate of variance V[E(Y|X i , X j )] when both X i and X j are fixed simultaneously should be corrected for individual contributions V i and V j .
[0024] For additive models Y(X), the sum of all first-order effects S1 i is equal to 1. This is not applicable for the general case of non-additive models, where second, third and higher-order effects (i.e., interactions between two, three or more input parameters) play an important role. The contribution due to higher-order effects can be estimated via total sensitivity index ST:
[0000] ST i ={V ( Y )− V[E ( Y|X ˜i )]}/ V ( Y ),
[0000] where V(Y)−V[E(Y|X ˜i )] is the total variance contribution from all terms in Eq. 1 that include X i . Obviously, ST i ≧S1 i , and the difference between the two represents the contribution from the higher-order interaction effects that include X i .
[0025] There are several methods available to estimate S1 i and ST i (see (Saltelli et al., 2008) for a comprehensive review).
[0026] In one embodiment, we apply Polynomial Chaos Expansion (PCE) [Wiener, 1938] to approximate the underlying optimized function y=f(α opt ,β). The advantage of applying PCE is that all GSA sensitivity indices can be calculated explicitly once the projection on the orthogonal polynomial basis is computed (Sudret, 2008).
[0027] In another embodiment, GSA sensitivity indices can be calculated using an algorithm developed by Saltelli (2002) that further extends a computational approach proposed by Sobol' (1990) and Homma and Saltelli (1996). The computational cost of calculating both S1 i and ST i is N(k+2), where k is a number of input parameters {X i } and N is a large enough number of model calls (typically between 1000 and 10000) to obtain an accurate estimate of conditional means and variances. However, with underlying physical model taking up to several hours to run, this computational cost can be prohibitively high. Therefore, we can use proxy-models that approximate computationally expensive original simulators. Quasi-random sampling strategies such as LPτ sequences (Sobol, 1990) can be employed to improve the statistical estimates of the computed GSA indices.
[0028] Once sensitivity indices are computed, uncertain β-parameters can be ranked according to values of S1. Parameters with the highest values of S1 should be selected for targeted measurement program. Reduction in uncertainty of these parameters will result in largest reduction in uncertainty of predicted model outcome. Parameters with lowest values of ST (typically, below 0.05) can be fixed at their base case value, thus reducing dimensionality of the underlying problem and improving the computational cost of the analysis.
[0029] The summary of the proposed general workflow is given in FIG. 1 .
[0030] The main steps include:
1. Identify control variables (α) and uncertain parameters (β). If applicable, define ranges for control variables. Define probability distribution functions (pdfs) for uncertain parameters. 2. Perform optimization under uncertainty (max F (α, β), where F=μ−λσ) and construct relevant points on the efficient frontier for various values of λ. 3. For a given point on the efficient frontier (defined by prescribed value of λ and corresponding values of control parameters α λ ), calculate GSA sensitivity indices and rank uncertain parameters β according to values of S1. 4. Perform additional measurements to reduce uncertainty of parameters β with high values of S1 and redefine pdfs for those parameters. 5. Optional: fix values of parameters β with low (e.g., below 0.05) values of ST to reduce dimensionality of the optimization problem. 6. Perform steps 2-5 until acceptable level of risk is achieved or until the decision is made that the desired level of performance cannot be achieved with the acceptable level of risk.
Illustrative Example
HPP Optimization Under Uncertainty
[0037] We now describe the application to a problem of HPP optimization demonstrating the method.
[0038] The underlying physical model along with the methods and numerical tools developed to simulate it are disclosed in “Method for Predicting Heterogeneous Proppant Placement and Conductivity” (U.S. Provisional Patent Application Ser. No. 61/870,901, filed Aug. 28, 2013 which is incorporated by reference above). Below we provide a short description of the main steps involved in calculating fracture conductivity resulting from HPP.
[0039] FIG. 2 shows a flow diagram highlighting the inputs and outputs utilized in our specific example of fracture conductivity when considering the heterogeneous placement of proppant from a vertical well intersecting a vertical hydraulic fracture as depicted in FIG. 3 . In this instance, the heterogeneity of proppant in the fracture is achieved through a combination of pulsing of the proppant into the fracture (see FIG. 4 ) and mixing phenomena (see FIG. 5 ) that are characterized by a mixing length.
[0040] FIG. 6 shows in more detail how the inputs are broken down into those related to the placement of the proppant and those related to the subsequent deformation and conductivity calculations. The complete list of model inputs utilized by the example application is provided in Table 1 along with descriptions of the inputs, their units and initial ranges used in this example.
[0041] We start by following the steps of the workflow disclosed in FIG. 1 .
Step 1.
[0042] Identify control variables (α) and uncertain parameters (β) and define their ranges and probability distributions.
[0000] Control variables (α) include:
1. Injector spacing 2. Pumping rate 3. Full cycle length 4. Proppant pulse length 5. Injector phase shift 6. Proppant Young's modulus 7. Proppant permeability (parameter was fixed in this study since the dominating flow mechanism in successful HPP job should be though the channels formed between the proppant pillars rather than through the proppant itself)
[0050] Ranges for control variables are given in Table 1. FIG. 4 illustrates some of these variables related to heterogeneous placement of proppant and consequently some systems can accommodate a pumping schedule that includes variations in proppant concentration with time.
[0000] Uncertain variables (β) include:
[0051] 1. Fracture aperture during placement
[0052] 2. Proppant mixing length
[0053] 3. Formation Young's modulus
[0054] 4. Formation Poisson ratio
[0055] Ranges for uncertain variables are given in Table 1. All variables were assumed to be uniformly distributed, except for “Proppant mixing length” that was assumed to be uniformly distributed on a log scale.
[0000]
TABLE 1
List of inputs for fracture conductivity calculation applied to injection
into a vertically oriented fracture from a vertical well.
Input
Description
Units
Range
Injector
Vertical distance between
Length (m)
0.5-3
spacing
injectors
Pumping
Volume per
0.1-0.5
rate
unit time (bpm)
Full cycle
Length in time of repeated
Time (s)
15-25
length
cycle of heterogeneous
injection
Proppant
Fraction of total injection
Non-
0.25-0.75
pulse length
period dedicated to
dimensional
proppant injection
Injector
The systematic delay be-
Non-
0-1
phase shift
tween the cycles of the
dimensional
injectors (as fraction of
total cycle length)
Fracture
Fracture assumed to have
Length (mm)
3-7
aperture
constant aperture during
during
displacement for this
placement
demonstration.
Proppant
The permeability of the
Length*Length
fixed at
permeability
permeability can be stress
(m 2 )
10 −10
under stress
dependent. In this
demonstration it was
assumed constant.
Proppant
Characteristic length scale
Length (m)
0.001-0.25
mixing
over which proppant and
length
clean fracturing fluid mix
during placement
Proppant
Assumed elastic constant
Stress (MPa)
50-500
Young's
characterizing compression
modulus
of proppant.
Formation
Stress (GPa)
5-50
Young's
modulus
Formation
Non-
0.15-0.35
Poisson
dimensional
ratio
Closure
Stress (MPa)
0.1-30
stress levels
Step 2.
[0056] Perform optimization under uncertainty (max F (α, β), where F=μ−λσ) and construct relevant points on the efficient frontier for various values of λ.
[0057] The underlying quantity to be optimized is fracture conductivity at a predefined closure stress (20 MPa in this example). In general, the objective function can be based on other performance metrics of proppant delivery and placement in the fracture including total hydrocarbon produced through the fracture, hydrocarbon production rate, and a financial indicator characterizing profitability of the fracturing job. Results of the optimization step comprise a risk profile shown in FIG. 7 . Corresponding values of mean, standard deviation for three λ points along with P10-P50-P90 estimates for facture conductivity corresponding to these three operational scenarios are given in Table 2.
[0000]
TABLE 2
Results of optimization with initial uncertainty.
λ = 0
λ = 1
λ = 2
Mean fracture conductivity (D · m)
248.15
232.05
193.6
Mean fracture conductivity (log 10)
−9.605
−9.634
−9.713
Standard deviation (log10 cycles)
1.21
1.15
1.10
P90 (D · m)
2.21
2.79
2.83
P50 (D · m)
562
507
408
P10 (D · m)
4582
3619
2622
Step 3.
[0058] For a given point on the efficient frontier (defined by prescribed value of λ and corresponding values of control parameters α λ ), calculate GSA sensitivity indices and rank uncertain parameters β according to values of S1.
[0059] We apply Polynomial Chaos Expansion approach to calculate GSA sensitivity indices for optimized models corresponding to values λ=0, 1, 2. The values for first-order sensitivity index (S1) and total sensitivity index (ST) for each uncertain parameter β are given in Table 3. For all three optimal points on the efficient frontier, “Proppant mixing length” is responsible for almost 70% of variance in predicted fracture conductivity. The second largest contributor is “Fracture aperture during placement” (15-20% of variance).
[0000]
TABLE 3
GSA sensitivity indices for optimized models (uncertain
parameters ranked according to S1).
λ = 0
λ = 1
λ = 2
S1
ST
S1
ST
S1
ST
Proppant mixing length
0.72
0.75
0.69
0.73
0.65
0.70
Fracture aperture during
0.17
0.18
0.17
0.18
0.19
0.20
placement
Formation Young's modulus
0.08
0.11
0.09
0.13
0.11
0.15
Formation Poisson ratio
0.00
0.00
0.00
0.00
0.00
0.00
Step 4.
[0060] Perform additional measurements to reduce uncertainty of parameters β with high values of S1 and redefine pdfs for those parameters.
[0061] Based on results of Step 3, “Proppant mixing length” was identified as a single largest contributor to variance of fracture conductivity at 20 MPa. For illustration, we assume that additional measurements were performed to reduce the uncertainty range of this parameter from 0.001 m-0.25 m (slightly more than two log 10 cycles) to 0.005-0.05 (one log 10 cycle) with uniform distribution on log scale.
Step 5.
[0062] Optional: fix values of parameters β with low (<0.05) values of ST to reduce dimensionality of the optimization problem.
[0063] Analyzing total-sensitivity values, we notice that “Formation Poisson ratio” has values very close to zero. Therefore, fixing this parameter in the middle of its original uncertainty range (0.15-0.35) will not significantly affect the outcome of the subsequent analysis (Sobol, 2001) while improving its computational cost since the dimensionality of the problem will be reduced.
Step 6.
[0064] Perform optimization step 2 with updated ranges of uncertain parameters.
[0065] Results of the optimization step are shown in FIG. 8 . Three points of the initial efficient frontier are also included for comparison. The updated efficient frontier has moved to the left (desired reduction in uncertainty) and slightly up. We note that the vertical direction of the shift in efficient frontier depends on underlying values in the physical quantity of interest (fracture conductivity) in the updated range of the uncertain parameter (Proppant mixing length). Corresponding values of mean, standard deviation for three λ points along with updated P10-P50-P90 estimates for facture conductivity corresponding to these three operational scenarios are given in Table 4. We observe the significant reduction in standard deviation (on log scale) compared to the initial case. The reduction in P10-P90 range on a linear scale is also noticeable.
[0000]
TABLE 4
Results of optimization with updated
uncertainty ranges (based on GSA).
λ = 0
λ = 1
λ = 2
Mean fracture conductivity (D · m)
743.39
698.31
589.72
Mean fracture conductivity (log 10)
−9.129
−9.156
−9.229
Standard deviation (log10 cycles)
0.68
0.59
0.53
P90 (D · m)
81
109
103
P50 (D · m)
981
943
782
P10 (D · m)
4494
3010
2219
[0066] The shift of efficient frontier to the left is expected in most cases. With the rare exception when the local variance underlying of values in the physical quantity of interest in the updated range of the uncertain parameter is higher than that in the initial range. Although even for this exception case, we argue that the disclosed approach provides iterative way to accurately estimate risk-reward profile for a given HPP job and allows one to avoid costly mistakes that would result in an underperforming fracture.
[0067] We disclosed a method for adaptive optimization of heterogeneous proppant placement under uncertainty. A predictive physics-based HPP model is used to estimate fracture conductivity under the desired closure stress. The input parameters of the model are divided into control variables and uncertain variables. The model is first optimized to obtain values of control variables maximizing mean fracture conductivity (at given closure stress) under initial uncertainty of formation properties. An efficient frontier may be obtained at this step to characterize the dependence between the optimized mean value of fracture conductivity and its uncertainty expressed by the standard deviation. Global sensitivity analysis is then applied to quantify and rank contributions from the uncertain input parameters to the standard deviation of the optimized values of fracture conductivity. The uncertain parameters are ranked according to their calculated sensitivity indices and additional measurements can be performed to reduce uncertainty in the high-ranking parameters. Constrained optimization of the model with reduced ranges of uncertain parameters is performed and a new efficiency frontier is obtained. In most cases, the points of the updated efficient frontier will shift to the left indicating reduction in risk associated with achieving the desired fracture conductivity. The disclosed method provides an adaptive GSA-optimization approach that results in iterative improvement of estimated risk-reward profile of an optimized HPP job under uncertainty.
[0068] Some embodiments may use a computer system including a computer processor (e.g., a microprocessor, microcontroller, digital signal processor or general purpose computer) for executing any of the methods and processes described herein. The computer system may further include a memory such as a semiconductor memory device (e.g., a RAM, ROM, PROM, EEPROM, or Flash-Programmable RAM), a magnetic memory device (e.g., a diskette or fixed disk), an optical memory device (e.g., a CD-ROM), a PC card (e.g., PCMCIA card), or other memory device. The memory can be used to store computer instructions (e.g., computer program code) that are interpreted and executed by the processor. | Apparatus and methods for delivering and placing proppant to a subterranean formation fracture including identifying control variables and uncertain parameters of the proppant delivery and placement, optimizing a performance metric of the proppant delivery and placement under uncertainty, calculating sensitivity indices and ranking parameters according to a relative contribution in total variance for an optimized control variable, and updating a probability distribution for parameters, repeating optimizing comprising the probability distribution, and evaluating a risk profile of the optimized performance metric using a processor. Some embodiments may deliver proppant to the fracture using updated optimized values of control variables. | 4 |
FIELD OF THE INVENTION
This invention relates to the polymerization of fluoropolymers into porous substrates. The fluoropolymer/substrate network that is present on the surface of the substrate and is also deposited into the substrate at appreciable depths. Depending upon the proportion of fluoropolymer relative to substrate, the fluoropolymer may provide a protective coating for the substrate and/or the substrate may improve the physical properties of the fluoropolymer.
TECHNICAL BACKGROUND OF THE INVENTION
Porous materials have a host of uses. Common uses for leather and porous polyurethane are to produce clothing and furniture. Common uses for wood include use as a building material and for the production of furniture. Polyimide compositions are known to have unique performance characteristics, which make them suitable for uses in the form of bushings, seals, electrical insulators, compressor vanes, brake linings, and others as described in U.S. Pat. No. 5,789,523. Para-oriented aromatic polyamides (para-aramids) are used to make fiber substrates that are useful for wear resistant application.
All of the porous materials described may degrade and decay over time by staining, wetting, warping, tearing or wearing. It is desirable to treat porous materials to improve resistance to wear, tear, creep, decay, and degradation by wetting, staining and warping, and to improve durability while maintaining the appearance of the materials.
For many years, textiles have been chemically treated to improve water and oil repellency. Different applications are commercially available to protect different kinds of substrates from oil and water staining. For example, Scotchgard® brand protector for fabrics sold by the 3M Company, and Teflon® Fabric Protector sold by E. I. du Pont de Nemours and Company, are available to consumers for use with textiles and fabrics. The use of granular fluoro-compounds is also discussed in Japanese Patent 05318413. The invention involves a method whereby a raw wood material is impregnated with a fluorinated microparticles having a diameter of 5 microns and a compound which changes to insoluble cured resin.
Other references include the treatment of microporous materials with fluoroacrylate to achieve permanent water and oil repellency. For example, U.S. Pat. No. 5,156,780 teaches a method for treating microporous substrates to achieve water and oil repellency while maintaining porosity. In the '780 method, the substrates are impregnated with a solution of monomer in a carrier solvent. The carrier solvent is first substantially removed from the substrate for the express purpose of leaving the monomer as a thin conformal coating on all internal and external substrate surfaces. In this manner, the monomer is converted to polymer and the polymer does not block the pores or restrict flow in subsequent use as a filtration membrane.
If enough fluoromonomer is polymerized into a porous structure, a point is reached at which there is more fluoropolymer than substrate and the composition can be considered a filled fluoropolymer. Fluoropolymers such as PTFE are commonly filled with substances such as glass fibers, graphite, asbestos, and powdered metals (Kirk-Othmer Encyclopedia of Chemical Technology, Fourth Edition, Volume 11, John Wiley and Sons, New York, pages 626 and 630). The filler is generally added for the purpose of improving some property of the fluoropolymer, such as creep or hardness.
Most often, filled fluoropolymers are made by physically mixing the fluoropolymer with the filler or by coagulating an aqueous fluoropolymer emulsion on the filler, but such methods have their problems. Adhesion of fluoropolymer to filler can be quite poor, particularly if the fluoropolymer does not wet the filler and penetrate its pores and finer surface features. Fluoropolymer melts can be very stiff making mixing/dispersion poor and nonuniform. Mechanical mixing can degrade some fillers, for example by breaking fine fibers. It is desirable to polymerize fluoromonomer onto the surface and into the pores of a substrate to achieve intimate fluoropolymer/substrate interpenetration and dispersion with minimal mechanical stress.
SUMMARY OF THE INVENTION
Disclosed in this invention is a process for preparing a fluoropolymer/substrate composition, comprising:
in the case of gaseous fluoromonomer
(a) contacting a porous substrate with a solution comprising an initiator dissolved in a suitable solvent;
(b) exposing said substrate and said initiator to gaseous fluoromonomer under polymerization temperature and pressure conditions wherein the fluoromonomer polymerizes into said substrate;
or in the case of liquid fluoromonomer
(a) preparing a solution comprising initiator and liquid fluoromonomer;
(b) contacting a porous substrate with said solution; and
(c) polymerizing the liquid fluoromonomer under polymerization temperature and pressure conditions wherein the fluoromonomer polymerizes into said substrate, optionally in the presence of gaseous fluoromonomer.
Also disclosed is a composition of matter made by a process for preparing a fluoropolymer/substrate composition, comprising:
in the case of gaseous fluoromonomer
(a) contacting a porous substrate with a solution comprising an initiator dissolved in a suitable solvent;
(b) exposing said substrate and said initiator to gaseous fluoromonomer under polymerization temperature and pressure conditions wherein the fluoromonomer polymerizes into said substrate;
or in the case of liquid fluoromonomer
(a) preparing a solution comprising initiator and liquid fluoromonomer;
(b) contacting a porous substrate with said solution; and
(c) polymerizing the liquid fluoromonomer under polymerization temperature and pressure conditions wherein the fluoromonomer polymerizes into said substrate optionally in the presence of gaseous fluoromonomer.
A further disclosure of the present invention is a composition of matter, comprising: a substrate having a surface wherein the substrate further comprises polymerized fluoropolymer, and wherein the substrate is an open pore structure having interconnecting pores throughout said substrate, and wherein fluoropolymer is present within and on the surface of said composition at a level from about 0.1 percent to about 300 percent of the weight of said substrate.
Also disclosed is the use of these compositions as filler materials for other polymers.
DETAILED DESCRIPTION OF THE INVENTION
The present invention discloses a fluoropolymer/substrate composition. The presence of fluoropolymer in the composition provides a protective material for the substrate and may also add aesthetic qualities to the substrate. A further advantage of the fluoropolymer/substrate composition is that the physical properties of the fluoropolymer are improved.
Also disclosed in the present invention is a method for preparing intimately interpenetrated fluoropolymer/substrate compositions that improve the functional lifetime and/or the appearance of any or all the components. The method disclosed for making the fluoropolymer/substrate composition leaves the initiator and the initiator carrier solvent in the substrate during polymerization and uses undiluted monomer or, in the preferred embodiment, gaseous monomer, to penetrate and block all pores to the greatest depth possible. In the present invention, the polymerized fluoromonomer partially or completely fills and blocks the pores of the substrate.
Coating the surface and blocking the pores of a substrate with fluoropolymer prevents or slows degradation by wetting and penetration of the substrate by agents such as water, acids, bases, foodstuffs, and cosmetics, thereby preventing staining, warping, and unwanted chemical or physical property changes in the substrate. As a case in point, the Ultrasuede®/PTFE composition of Example 8 below wets less readily than untreated Ultrasuede™. Coating the surface and blocking the pores of a substrate with fluoropolymer can also slow mechanical degradation by such means as abrasion, creep, or tearing. As a case in point, the polyimide/PTFE composition of Example 2A abraded 8× more slowly than untreated polyimide.
Going further, once the volume of polymerized fluoropolymer exceeds that of the substrate or once the fluoropolymer/substrate network has been blended into pure fluoropolymer, the substrate can then be considered as dispersed in the fluoropolymer for the purpose of modifying fluoropolymer properties. These compositions are commonly referred to as “filled fluoropolymer.” For example, intimately interpenetrated porous polyimide or aramid particulates can be added to poly(tetrafluoroethylene) to potentially decrease PTFE creep. In a process disclosed in the present invention, the fluoromonomer is polymerized both on the surfaces and into the pores of a substrate to achieve intimate fluorpolymer/susbtrate interpenetration and dispersion. The filled fluoropolymer is prepared with minimal mechanical stress. This process reduces degradation, and thereby, offers a solution to the problem of degradation that occurs with mechanical mixing.
The invention involves a process for the in situ polymerization of fluoromonomer into substrates. Polymerization temperatures range from about 0° C. to about 300° C., preferably from about 0° C., to about 100° C., most preferably from about 5° C. to about 30° C. For those substrates that retain their rigid pore structures at high temperatures and do not thermally decompose, polymerizations can be run at temperatures up to about 300° C.
The process of the present invention uses fluoromonomer in either the gaseous or liquid state. Gaseous monomers include tetrafluoroethylene (TFE), trifluoroethylene, vinylidene fluoride, chlorotrifluoroethylene, hexafluoroisobutylene and perfluoro methyl vinyl ether. Liquid monomers include 4,5-difluoro-2,2-bis(trifluoromethyl)-1,3-dioxole (PDD), perfluoro (2-methylene-4-methyl-1,3-dioxolane (PMD) and perfluoro propyl vinyl ether. These monomers may be homopolymerized or copolymerized to make compositions known to those skilled in the art. Examples include tetrafluoroethylene homopolymer and tetrafluoroethylene/4,5-difluoro-2,2-bis(trifluoromethyl)-1,3-dioxole copolymer.
By “porous substrate” is meant any solid material penetrated throughout with interconnecting pores of a size such as to allow absorption of liquid initiator solution and monomer. The porous substrates can take any form including microscopic particulates, microscopic fibers, coarse particulates, pulp, fibrids, chunks, blocks, uncompressed, partially or fully compressed parts, sheets, films, membranes, and coatings. Porous substrates are not meant to include materials such as cloth where the only mechanism of fluoropolymer entrainment is gross entrapment between separate fibers rather than subsurface penetration into a substrate's pores. This process works with any porous substrate that does not inhibit fluoromonomer polymerization. Substrates not inhibiting polymerization include wood, wood by-products such as paper, p-aramid fibers, molded polyimide parts, porous polyurethane and leather. Whether a substrate will inhibit polymerization must be determined empirically substrate by substrate and may vary for the same substrate, depending upon prior finishing and treatment.
The present invention also provides a fluoropolymer/substrate composition wherein the substrates are open structures with interconnecting pores throughout their bulk and the level of fluoropolymer in the fluoropolymer/substrate composition is about 0.1% to about 300% of the weight of the substrate. Substrates useful in this invention include wood, paper, leather, porous polyurethane, and aramids and polyimides that have been precipitated as porous particulates or porous fibers and then left wet, dried, or molded only so far as to preserve enough porosity for subsequent penetration by fluoromonomer and initiator. Preferred substrates are porous aramid, polyimide particulates and polyimide parts.
When a preferred substrate is used, the porous aramid or polyimide is immersed for about 1 minute in a 0.1 to 0.2 M solution of hexafluoropropylene oxide dimer peroxide (DP) 1
CF 3 CF 2 CF 2 OCF(CF 3 )(C═O)OO(C═O)CF(CF 3 OCF 2 CF 2 CF 3 1,DP
in CF 3 CFHCFHCF 2 CF 3 solvent. The excess solvent is filtered off or is drained from the aramid or polyimide, and the still damp polymer placed in a container with 1 atmosphere pressure of tetrafluoroethylene gas until the substrate has gained preferably 5 to 20% of its weight by polymerization of the tetrafluoroethylene to poly(tetrafluoroethylene).
The preferred aramids are poly(p-phenylene terephthalamide) (hereinafter “PPD-T”) fibers and poly(m-phenylene isophthalamide) (hereinafter “MPD-I”) in the form of fiber, particles, pulp or fibrids, that are dried, or never-dried. Examples of preferred aramids are poly(p-phenylene terephthalamide) fibers sold by the DuPont Company under the tradename “Kevlar®”, and poly(m-phenylene isophthalamide) sold by the DuPont Company under the tradename Nomex®.
A “never-dried aramid” means an aramid coagulated from a solution by contact with a non-solvent (usually an aqueous bath of some sort, such as water or an aqueous solution). When contacted with the non-solvent, the polymer coagulates and most of the solvent is removed from the aramid. The aramid has an open sponge-like structure, which usually contains about 150-200% by weight of the aramid of non-solvent (again, usually water). It is this open sponge-like structure, which has imbibed the non-solvent, which is referred to herein as “never-dried aramid”.
By PPD-T is meant the homopolymer resulting from mole-for-mole polymerization of p-phenylenediamine and terephthaloyl chloride and, also, copolymers resulting from incorporation of small amounts of other aromatic diamine with the p-phenylene diamine and of small amounts of other aromatic diacid chloride with the terephthaloyl chloride. Examples of other acceptable aromatic diamines include m-phenylene diamine, 4,4′-diphenyldiamine, 3,3′-diphenyldiamine, 3,4′-diphenyldiamine, 4,4′-oxydiphenyldiamine, 3,3′-oxydiphenyldiamine, 3,4′-oxydiphenyldiamine, 4,4′-sulfonyldiphenyldiamine, 3,3′-sulfonyldiphenyldiamine, 3,4′-sulfonyldiphenyldiamine, and the like. Examples of other acceptable aromatic diacid chlorides include 2,6-naphthalene-dicarboxylic acid chloride, isophthaloyl chloride, 4,4′-oxydibenzoyl chloride, 3,3′-oxydibenzoyl chloride, 3,4′-oxydibenzoyl chloride, 4,4′-sulfonyldibenzoyl chloride, 3,3′-sulfonyldibenzoyl chloride, 3,4′-sulfonyldibenzoyl chloride, 4,4′-dibenzoyl chloride, 3,3′-dibenzoyl chloride, 3,4′-dibenzoyl chloride, and the like. As a general rule, other aromatic diamines and other aromatic diacid chlorides can be used in amounts up to as much as about 10 mole percent of the p-phenylene diaamine or the terephthaloyl chloride, or perhaps slightly higher, provided only the other diamines and diacid chlorides have no reactive groups which interfere with the polymerization reaction.
By MPD-I is meant the homopolymer resulting from mole-for-mole polymerization of m-phenylenediamine and isophthaloyl chloride and, also, copolymers resulting from incorporation of small amounts of other aromatic diamine with the m-phenylene diamine and of small amounts of other aromatic diacid chloride with the isophthaloyl chloride. Examples of other acceptable aromatic diamines include p-phenylene diamine, 4,4′-diphenyldiamine, 3,3′-diphenyldiamine, 3,4′-diphenyldiamine, 4,4′-oxydiphenyldiamine, 3,3′-oxydiphenyldiamine, 3,4′-oxydiphenyldiamine, 4,4′-sulfonyldiphenyldiamine, 3,3′-sulfonyldiphenyldiamine, 3,4′-sulfonyldiphenyldiamine, and the like. Examples of other acceptable aromatic diacid chlorides include 2,6-naphthalenedicarboxylic acid chloride, terephthaloyl chloride, 4,4′-oxydibenzoyl chloride 3,3′-oxydibenzoyl chloride, 3,4′-oxydibenzoyl chloride, 4,4′sulfonyldibenzoyl chloride, 3,3′-sulfonyldibenzoyl chloride, 3,4′-sulfonyldibenzoyl chloride, 4,4′-dibenzoyl chloride, 3,3′-dibenzoyl chloride, 3,4′-dibenzoyl chloride, and the like. As a general rule, other aromatic diamines and other aromatic diacid chlorides can be used in amounts up to as much as about 10 mole percent of the m-phenylene diamine or the isophthaloyl chloride, or perhaps slightly higher, provided only the other diamines and diacid chlorides have no reactive groups which interfere with the polymerization reaction.
The process invention disclosed herein works for most organic initiators commonly used for fluoroolefin polymerizations, including, but not limited to, diacylperoxides, peroxides, azos and peroxydicarbonates. The preferred initiator is DP. DP has a half-life of about 4 hours at 20° C. which means that DP lasts long enough for a polymerization run to be set up at room temperature without excessive initiator loss and yet DP still reacts fast enough at room temperature for polymerizations to run to completion fairly quickly. Preferred run times are from about 4 to about 24 hours.
In the preferred embodiment of this invention, the initiator is first synthesized in any solvent that is compatible with fluoroolefin polymerization and the initiator solution then absorbed into the substrate. Suitable solvents comprise chlorofluorocarbons such as Freon® 113 (CFCl 2 CF 2 Cl), hydrofluorocarbons, such as Vertrel® XF (HFC-43-10mee; 2,3-dihydroperfluoropentane) specialty fluid, perfluorocarbons, such as perfluorohexane, perfluoroethers, such as Fluorinert® FC-75 sold by 3M Company, perfluoroamines, such as Fluorinert® FC 40, and perfluorodialkylsulfides, such as CF 3 CF 2 CF 2 CF 2 SCF 2 CF 2 CF 2 CF 2 CF 3 . The preferred solvents for DP are Vertrel® XF and Freon® E1(CF 3 CF 2 CF 2 OCFHCF 3 ).
In this invention, the preferred initiator solution comprises a solution of hexafluoropropylene oxide dimer peroxide [DP] in Vertrel® XF (CF 3 CFHCFHCF 2 CF 3 ). It is further preferred that the fluoromonomer used in this process is tetrafluoroethylene. TFE polymerizes to form PTFE.
Substrates specfically exemplified for the present invention include wood, molded polyimide parts, porous polyimide powder, porous para-aramids such as poly(para-phenylene terephthalamide) [PPD-T] in the forms of powder, pulp and/or fiber, and porous meta-aramids, such as poly(m-phenylene isophthalamide)[MPD-I] in the forms of powder, fibers or fibrids, porous polyurethane, and leather (pigskin and cowskin).
In the case of liquid fluoromonomer, such as PDD and PMD, the carrier solvent can be the monomer or the monomer containing a small amount of initiator solution (for example, DP in a Freon® solvent).
EXAMPLES
Example 1
TFE Polymerization Into As-Molded Polyimide Parts
A. Preparation of molded polyimide test bars with variable porosity
Polyimide resin powder used in the following Examples 1, 2 and 3 was prepared from pyromellitic dianhydride and 4,4′-oxydianiline, according to the procedures of U.S. Pat. No. 3,179,614 or U.S. Pat. No. 4,622,384. Polyimide powder samples weighing 2.1 to 2.5 g were cold pressed at room temperature into tensile bars. These tensile bars were dogbone shaped, measuring 90 mm long by 5 mm to 10 mm wide. In order to vary the porosity of the tensile bars, six different compressive forces were used, 10,000 psi, 20,000 psi, 30,000 psi, 40,000 psi, 50,000 psi, and 100,000 psi, the resulting bars being called the 10K, 20K, 30K, 40K, 50K, and 100K bars respectively. After pressing, the bars had thicknesses typically running from 2.7 to 3.3 mm. When the bars were dried overnight in a 75° C. oven, they lost 1 to 3% of their weight. Pore volumes for dried polyimide powder starting material and dried tensile bars measured by nitrogen porosimetry are shown in the Table 1 below.
TABLE 1
Sample
Pore Volume forPores 17 to 3000Å
Starting Powder
0.18 cc/g
10K Bar
0.09 cc/g
20K Bar
0.050 cc/g
30K Bar
0.01 cc/g
40K Bar
0.002 cc/g
50K Bar
nil
100K Bar
nil
B. Atmospheric Pressure TFE Polymerization Tensile Tests
One each of a 10K, a 50K, and a 100K bar were soaked at −15° C. in initiator solution, a ˜0.14 M DP 1 solution in Vertrel™ XF solvent (CF 3 CFHCFHCF 2 CF 3 ). After 3 hours, the bars were pulled from the initiator solution, excess initiator solution allowed to drain, and then loaded into a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was evacuated and filled 3× with N 2 and then 3× with tetrafluoroethylene (TFE). The bag was inflated with TFE and allowed to stand ˜20 hours overnight at room temperature. The next morning the three test bars were recovered and loose white PTFE powder was wiped off the surface. After 4 days of devolatilization under pump vacuum, the bars were reweighed with the weight changes shown in the table below. The bars were further compressed to 100,000 psi at room temperature. These bars were then finished by heating to 405° C. for three hours. Tensile tests on these bars are also shown in the table below versus control polyimide bars containing no PTFE. Fluorine analyses on the broken remains of the bars are shown in Table 2 below.
TABLE 2
%
Weight % Fluorine
Nominal PTFE
Elongation
Combustion by
Sample
Weight Gain
PSI at Break
at Break
Analysis
Control
11,500
10.9
—
10K
6.5 wt %
Broke when
—
2.0% F
compressed
50K
−0.5 wt %
11,400
9.1
0.71% F
100K
−0.6 wt %
11,000
11.3
0.17% F
The apparent weight losses for the 50K and 100K bars needs comment. The starting polyimide powder and bars showed 1 to 3% weight loss when dried overnight at 75° C. The polyimide bars used here for TFE polymerizations were not dried before the TFE polymerization step but were devolatilized afterwards. The apparent weight change over the course of the experiment thus is the net result of volatiles loss and PTFE weight gain. Apparently volatiles loss is greater than PTFE weight gains for bars compressed at 50,000 and 100,000 psi.
C. High Pressure TFE Polymerization.
One each of a 10K, a 50K, and a 100K bar were soaked at −15° C. in initiator solution, a ˜0.15 M DP 1 solution in Vertrel™ XF solvent (CF 3 CFHCFHCF 2 CF 3 ). After 30 minutes, the three bars were pulled from the initiator solution allowing excess initiator to drain away and then stored on dry ice until they could be loaded into a 400 ml autoclave prechilled to −20° C. The autoclave was evacuated and filled with 10 g of TFE. Polymerization was allowed to run overnight at room temperature, TFE pressure in the autoclave reaching a maximum of 111 psi at 16.3° C. The next morning, the test bars were recovered from a large volume of white PTFE fluff, using a tissue to wipe loose white PTFE off the surface. After 12 days of devolatilization under pump vacuum, the bars were analyzed for fluorine content by combustion analysis with the results shown in Table 3 below.
TABLE 3
Bar
Fluorine by Combustion Analysis
10K
13.97 wt % F
50K
0.93 wt % F
100K
0.51 wt % F
The fluorine contents are higher than observed when the TFE polymerization was run at atmospheric pressure in section B immediately above.
D. Atmospheric Pressure Polymerization
Groups of four to eight 20K, 30K, and 40K bars were soaked at ˜15° C. in 20 to 30 ml of initiator solution, ˜0.16 M DP 1 in Vertrel™ XF solvent (CF 3 CFHCFHCF 2 CF 3 ). After 60 minutes, the bars were pulled from the initiatior solution allowing excess initiator to drain away and then loaded into a 6×9″ziplock polyethylene bag equipped with a gas inlet valve. The bag was evacuated and filled 3× with N 2 and then 3× with tetrafluoroethylene (TFE). The bag was inflated with TFE and allowed to stand overnight at room temperature. The next morning the test bars were recovered, loose white PTFE powder wiped off the surface, and dried in a 75° C. vacuum oven. Three bars from each set were further compressed at 100,000 psi at room temperature and then sintered by raising temperature at 1.5° C./min to 405° C. and holding at 405° C. for 3 hours. Tensile tests were performed and the broken fragments analyzed for fluorine content as shown in the table below. The data results in Table 4 below show that polymerization of TFE into an as-molded polyimide bar does not have a major effect on ultimate tensile properties.
TABLE 4
Weight Percent Fluorine by
PSI at
Elongation
Combustion Analysis
Test Bar
Break
at Break
From Center of Bar
From End of Bar
20K
10,980
14.5%
0.79
0.59
20K
10,930
9.5%
20K
10,676
8.5%
30K
10,974
9.8%
0.49
0.14
30K
10,209
6.3%
30K
11,335
7.8%
40K
11,241
8.5%
0.66
0.56
40K
11,699
8.9%
40K
11,312
8.1%
Example 2
Porous Polyimide Powder, Atmospheric Pressure TFE Polymerization
A. Polyimide/PTFE Analysing for 6.34% Fluorine
A 500-ml round-bottomed flask loaded with 15.59 g of polyimide powder and ˜55 ml of Vertrel™ XF was chilled overnight in a −15° C. refrigerator. The next morning 5 ml of ˜0.16 M DP in Vertrel™ XF was added and then excess solvent was rapidly pulled off first using a rotary evaporator (˜20 min) and then a vacuum pump (˜13 min) so as to keep the reaction mixture cold by evaporative cooling. The polyimide powder, now impregnated with DP, was loaded into a 6×9″ Ziplock® polyethylene bag equipped with a gas inlet valve. The bag was inflated and then evacuated 3× with N 2 and 3× with tetrafluoroethylene (TFE). The bag was inflated a final time with TFE and polymerization allowed to run until about half the TFE had been reacted as judged by visible deflation of the bag. This took about 72 minutes. The surface of the polyimide powder remained yellow indicating that the bulk of the PTFE polymerization was occurring within the pores of the particles rather than on the surface. The recovered polyimide powder weighed 19.33 g upon removal from the bag, 16.48 g after 147 minutes in a 75° C. vacuum oven, and 16.38 g after continuing another 70 hours in the 75° C. vacuum oven. Weight gain was 0.79 g or 5.1% relative to the weight of the starting polyimide powder. Combustion analysis on the product found 6.34 wt % fluorine. Finding 6.34 wt % fluorine versus a 5.1 wt % gain overall is, as observed with the test bars above, consistent with starting with a raw polyimide powder that had not been devolatilized.
Samples of this powder were compressed at 100,000 psi at room temperature into three tensile bars measuring 90 mm long by 5 mm to 10 mm wide (dogbone-shaped). These bars were then finished by heating to 405° C. for three hours. In tensile tests these bars broke on average at 6,675 psi with 4.7% elongation. Combustion analysis on the broken pieces found 4.99 wt % fluorine.
The polyimide/PTFE composite made in this experiment was tested for resistance to wear using the method described in U.S. Pat. No. 5,789,523, column 4, line 51. The powder was compressed at 100,000 psi into a disk 1″ in diameter by about 0.25″ thick. This disk was then heated to 405° C. for three hours. After cooling to room temperature, the parts were machined to final dimensions for test specimens. The 0.25″ (6.35 mm wide) contact surface of the wear/friction disk was machined to such a curvature that it conformed to the outer circumference of the 1.375″ (34.9 mm) diameter ×0.375″ (9.5 mm) wide metal mating ring. The disks were oven dried and maintained dry over desiccant until tested. Wear tests were performed using a Falex No. 1 Ring and Block Wear and Friction Tester. The equipment is described in ASTM Test method D2714. After weighing, the dry polyimide/PTFE disk was mounted against the rotating metal ring and loaded against it with the selected test pressure. Rotational velocity of the ring was set at the desired speed. No lubricant was used between the mating surfaces. The rings were SAE 4620 steel, Rc 58-63, 6-12 RMS. A new ring was used for each test. Test time was usually 24 hours, except when friction and wear were high, in which case the test was terminated early. At the end of the test time, the block was disconnected, weighed, and the wear calculated using the following calculation: Wear volume ( cc / hr ) = Weight Lost ( grams ) Material density ( grams / cc ) × Test duration ( hours )
In this test the wear volume of the polyimide/PTFE sample was at least 8× less than for a polyimide sample free of PTFE.
B. Polyimide/PTFE Analyzing for 14.15% Fluorine
A 500-ml round-bottomed flask loaded with 15.82 g of polyimide powder and ˜55 ml of Vertrel® XF was chilled for 1 hour in a −15° C. refrigerator. About 5 ml of ˜0.16 M DP in Vertrel® XF was added and then excess solvent was rapidly pulled off first using a rotary evaporator (10-15 min) and then a vacuum pump (˜5 min) so as to keep the reaction mixture cold by evaporative cooling. The polyimide powder, now impregnated with DP was loaded into a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was purged of air by inflating and evacuating the bag 3× with N 2 and 3× with tetrafluoroethylene (TFE). Polymerization was started by inflating the bag with TFE and allowing polymerization to deflate the bag over about a 2 hour period. The still yellow polyimide powder was dried overnight in an 88° C. vacuum oven. Combustion analysis on the product found 14.15 wt % fluorine.
Samples of this powder were compressed at 100,000 psi at room temperature into three tensile bars measuring 90 mm long by 5 mm to 10 mm wide (dogbone-shaped). These bars were then heated from to 405° C. for three hours. In tensile tests these bars broke on average at 1,369 psi with 0.5% elongation. Combustion analysis on the broken pieces found 13.89 wt % fluorine.
C. Polyimide/PTFE Analysing for 19.93% Fluorine
A 500-ml round-bottomed flask loaded with −15.51 g of polyimide powder and ˜55 ml of Vertrel™ XF was chilled for 1 hour in a −15° C. refrigerator. About 5 ml of ˜0.16 M DP in Vertrel™ XF was added and then excess solvent was rapidly pulled off first using a rotary evaporator (˜15 min) and then a vacuum pump (˜4 min) so as to keep the reaction mixture cold by evaporative cooling. The polyimide powder, now impregnated with DP, was loaded into a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was purged of air by inflating and evacuating the bag 3× with N 2 and 3× with tetrafluoroethylene (TFE). Polymerization was started by repeatedly inflating the bag with TFE and allowing polymerization to deflate the bag twice, the deflations taking 40 minutes and overnight respectively. The still yellow polyimide powder was dried for ˜4 days in a 75° C. vacuum oven. Combustion analysis on the product found 19.93 wt % fluorine.
Samples of this powder were compressed at 100,000 psi at room temperature into three tensile bars measuring 90 mm long by 5 mm to 10 mm wide (dogbone-shaped). These bars were then heated to 405° C. for three hours. In tensile tests these bars broke on average at 1,385 psi with 0.6% elongation. Combustion analysis on the broken pieces found 18.76 wt % fluorine.
D. Polyimide/PTFE Analysing for 23.99% Fluorine
A 500-ml round-bottomed flask loaded with 15.66 g of polyimide powder and ˜55 ml of Vertre® XF was chilled overnight in a −15° C. refrigerator. The next morning 5 ml of ˜0.16 M DP in Vertre® XF was added and then excess solvent was rapidly pulled off first using a rotary evaporator (˜18 min) and then a vacuum pump (˜9 min) so as to keep the reaction mixture cold by evaporative cooling. The polyimide powder, now impregnated with DP, was loaded into a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was purged of air by repeatedly inflating and evacuating the bag 3× with N 2 and 3× with tetrafluoroethylene (TFE). Polymerization was started by repeatedly inflating the bag with TFE and allowing polymerization to deflate the bag three times, the deflations taking 55, 50, and 130 minutes respectively. The still yellow polyimide powder was dried overnight (˜17 hrs) in a 75° C. vacuum oven. Combustion analysis on the product found 23.99 wt % fluorine.
Samples of this powder were compressed at 100,000 psi at room temperature into three tensile bars measuring 90 mm long by 5 mm to 10 mm wide (dogbone-shaped). These bars were then heated to 405° C. for three hours. In tensile tests these bars broke on average at 1,688 psi with 0.9% elongation. Combustion analysis on the broken pieces found 24.26 wt % fluorine.
E. Polyimide/PTFE Analysing for 27.77% Fluorine
A 500-ml round-bottomed flask loaded with 16.01 g of polyimide powder and ˜55 ml of Vertrel™ XF was chilled for 1 hour in a −15° C. refrigerator. About 5 ml of ˜0.16 M DP in Vertrel™ XF was added and then excess solvent pulled off first using a rotary evaporator (˜12 min) and then a vacuum pump (˜7 min) so as to keep the reaction mixture cold by evaporative cooling. The polyimide powder, now impregnated with DP, was loaded into a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was purged of air by inflating and evacuating the bag 3× with N 2 and 3× with tetrafluoroethylene (TFE). Polymerization was started by repeatedly inflating the bag with TFE and allowing polymerization to deflate the bag four times, the deflations taking 21, 23, 23, and 42 minutes respectively. The still yellow polyimide powder was dried overnight (˜19 hrs) in a 75° C. vacuum oven. Combustion analysis on the product found 27.77 wt % fluorine.
Samples of this powder were compressed at 100,000 psi at room temperature into three tensile bars measuring 90 mm long by 5 mm to 10 mm wide (dogbone-shaped). These bars were then heated to 405° C. for three hours. In tensile tests these bars broke on average at 1442 psi with 0.6% elongation. Combustion analysis on the broken pieces found 26.32 wt % fluorine.
F. Polyimide/PTFE Analyzing for 37. 94% Fluorine
A round-bottomed flask chilled to ˜0° C. was loaded with 16.6 g of polyimide powder, 40 ml of Vertrel™ XF, and 10 ml of ˜0.16 M DP in Vertrel™ XF. Excess solvent was rapidly pulled off first using a rotary evaporator and then a pump so as to keep the reaction mixture cold by evaporative cooling. The polyimide powder, now impregnated with DP, was loaded into a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was purged of air by inflating and evacuating the bag 3× with N 2 and 3× with tetrafluoroethylene (TFE). Polymerization was start TFE and allowing polymerization to deflate the bag over an afternoon and then overnight. The next morning the polyimide powder was recovered. After three days of devolatilization under pump vacuum, combustion analysis on the product found 37.94 wt % fluorine.
Samples of this powder were compressed at 100,000 psi at room temperature into five tensile bars measuring 90 mm long by 5 mm to 10 mm wide (dogbone-shaped). These bars were then heated to 405° C. for three hours. In tensile tests these bars broke on average at 733 psi with 0.4% elongation. Combustion analysis on the broken pieces found 31.85 wt % fluorine.
G. Summary of Results on Polyimide Powder with PTFE Polymerized into its Pores Table 5 below summarizes the results for parts A through F above.
TABLE 5
Weight % Fluorine by
Combustion Analysis
After Bar
Starting
Pressed and
Polyimide/PTFE
Heated
PSI at Break
Elongation at Break
6.34%
4.99%
6,675 psi
4.7%
14.15%
13.89%
1,369 psi
0.5%
19.93%
18.76%
1,385 psi
0.6%
23.99%
24.26%
1,688 psi
0.9%
27.77%
26.32%
1,442 psi
0.6%
37.94%
31.85%
733 psi
0.4%
Example 3
Porous Polyimide, Atmospheric Pressure TFE Polymerization; CO 2 as Carrier for Initiator
A 400-ml stainless steel autoclave was loaded first with 15.05 g of polyimide powder and then with a 100-g layer of dry ice on top. Five ml of ˜0.16 M DP in Vertrel® XF was poured over the dry ice. The autoclave was sealed and its contents shaken without any provision for additional cooling. As soon as the contents of the autoclave reached 0° C., the CO 2 was vented. The polyimide powder was recovered and chilled on dry ice until it could be transferred to a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was inflated and evacuated 3× with N 2 and 3× with tetrafluoroethylene (TFE). The bag was inflated a final time with TFE. Polymerization was allowed to run 132 minutes until about a quarter of the TFE had been reacted as judged from deflation of the bag. Drying for 21 hours in a 75° C. vacuum oven gave 13.69 g of polyimide powder that analyzed for 2.49 wt % fluorine by combustion analysis.
Example 4
Porous Poly(P-Phenylene Terephthalamine) Powder, Atmospheric Pressure TFE Polymerization
Porous poly(p-phenylene terephthalamide) particulates were prepared by adding poly(p-phenylene terephthalamide) precipitate as made in N-methylpyrrolidinone/CaCI 2 to water, filtering, rinsing with water, and filter. A 25.6 g sample of these poly(p-phenylene terephthalamide) particulates was soaked in 30 ml of 0.18 M HFPO dimer peroxide in Vertrel™ XF at −15° C. After 15 minutes, the poly(p-phenylene terephthalamide) was separated by vacuum filtration, stopping filtration as soon as the liquid flow seemed near an end. The poly(p-phenylene terephthalamide), still damp with initiator solution, was transferred to a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was evacuated and filled 3× with N 2 and 3× with TFE. The bag was inflated a final time with TFE and the polymerization allowed to run at room temperature. Over the next several hours the bag was reinflated four times with TFE. Before reinflation, the contents of the bag were shaken and/or squeezed lightly with finger pressure to break up nascent lumps. The polymerization was allowed to continue overnight at room temperature. The next morning the contents of the bag were poured out, avoiding as much as possible entrainment of white PTFE deposits attached to the walls of the bag. After two days under pump vacuum, the product consisting largely of yellow granules plus a few white PTFE flakes from the wall of the bag, weighed 32.9 g for a weight gain of 28%. Taking just the yellow granules, combustion analysis found 15.70 wt % fluorine.
Example 5
Porous Poly(P-Phenylene Terephthalamide) Powder, Atmospheric Pressure TFE Polymerization
A. Lower PTFE Loading
Porous poly(p-phenylene terephthalamide) particulates were prepared by adding poly(p-phenylene terephthalamide) precipitate as made in N-methylpyrrolidinone/CaCl 2 to water, filtering, rinsing with water, and filter. These particulates were then dried overnight in a 150° C. vacuum oven. A 36 mL sample of ˜0.17 M HFPO dimer in Vertrel™ XF at −15° C. was added to 360 ml of room temperature Vertrel™ XF with swirling for ˜1 minute. This initiator solution was then added immediately to 218.1 g of dried poly(p-phenylene terephthalamide) in a large crystallizing dish. In order to ensure thorough mixing, the contents of the crystallizing dish were worked for 1 minute with a spatula. The resulting poly(p-phenylene terephthalamide) slurry was filtered using a Buchner funnel, the vaccuum being applied for ˜1 minute so as to leave the poly(p-phenylene terephthalamide) still damp with initiator solution (weight 295 g). The poly(p-phenylene terephthalamide) was transferred to a 8×10″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was evacuated and filled 3× with N 2 and 3× with TFE. The bag was inflated a final time with TFE to a height of ˜3.5 inches and the polymerization allowed to run at room temperature. As TFE polymerization proceeded the bag periodically deflated to a near vacuum and was then reinflated with TFE gas first 10 and again 18 minutes into the run. Throughout the run, the bag was noticeably warm to the touch. After the last deflation, 28 minutes into the run, the contents of the bag were transferred back to a large crystallizing dish. Residual volatiles were removed by first putting under pump vacuum overnight and then in a 150° C. vacuum oven overnight. The product consisting largely of yellow granules, weighed 227.8 g for a weight gain of 4.4% and combustion analysis found 4.16 wt % fluorine or 5 wt % PTFE in reasonable agreement with the measured weight gain. It should be noted that when running with an oven dried poly(p-phenylene terephthalamide) sample and at much larger scale than in Example 4 above, no free PTFE particulates on the walls of the bag or mixed in with the poly(p-phenylene terephthalamide) were apparent to the eye.
B. Intermediate PTFE Loading
Porous poly(p-phenylene terephthalamide) particulates were prepared by adding poly(p-phenylene terephthalamide) precipitate as made in N-methylpyrrolidinone/CaCl 2 to water, filtering, rinsing with water, and filter. These particulates were then dried overnight in a 150° C. vacuum oven. A 36 mL sample of ˜0.17 M HFPO dimer in Vertrel™ XF at −15° C. was added to 360 ml of room temperature Vertrel™ XF with swirling. This initiator solution was then added immediately to 218 g of dried poly(p-phenylene terephthalamide) in a large crystallizing dish. In order to ensure thorough mixing the contents of the crystallizing dish were worked for 1 minute with a spatula. The resulting poly(p-phenylene terephthalamide) slurry was filtered using a Buchner funnel, the vacuum being applied for only 50 seconds so as to leave the poly(p-phenylene terephthalamide) still damp with initiator solution. The poly(p-phenylene terephthalamide) was transferred to an 8×10″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was evacuated and filled 3× with N 2 and 3× with TFE. The bag was inflated a final time with TFE and the polymerization allowed to run at room temperature. As TFE polymerization proceeded the bag periodically deflated to a near vacuum and was then reinflated ˜2 to 3″ tall with TFE gas 8, 14, 25, 37, 46, 62, and 80 minutes into the run. During much of the run, the bag was noticeably warm to the touch. After the last deflation, 98 minutes into the run, the contents of the bag were transferred back to a large crystallizing dish. Residual volatiles were removed by first putting under pump vacuum overnight and then in a 150° C. vacuum oven overnight. The product consisting largely of yellow granules, weighed 244 g for a weight gain of 12% and combustion analysis found 8.40 wt % fluorine or 11 wt % PTFE in reasonable agreement with the measured weight gain.
C. Higher PTFE Loading
Porous poly(p-phenylene terephthalamide) particulates were prepared by adding poly(p-phenylene terephthalamide) precipitate as made in N-methyl-pyrrolidinone/CaCl 2 to water, filtering, rinsing with water, and sucking dry on the filter. These particulates were then dried overnight in a 150° C. vacuum oven. A 36 mL sample of ˜0.17 M HFPO dimer in Vertrel® XF at −15° C. was added to 360 ml of room temperature Vertrel® XF with swirling. This initiator solution was then added immediately to 217 g of dried poly(p-phenylene terephthalamide) in a large crystallizing dish. In order to ensure thorough mixing the contents of the crystallizing dish were worked for 1 minute with a spoon. The resulting poly(p-phenylene terephthalamide) slurry was filtered using a Buchner funnel, the vaccuum being applied for only 50 seconds so as to leave the poly(p-phenylene terephthalamide) still damp with initiator solution. The poly(p-phenylene terephthalamide) was transferred to a 8×10″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was evacuated and filled 3× with N 2 and 3× with TFE. The bag was inflated a final time with TFE and the polymerization allowed to run at room temperature. As TFE polymerization proceeded the bag periodically deflated to a near vacuum and was then reinflated ˜2 to 4″ tall with TFE gas 9, 18, 27, 40, 50, 57, 67, 81, 97, 110, 133, 161, 199, and 250 minutes into the run. During much of the run, the bag was noticeably warm to the touch. After the last deflation, 303 minutes into the run, the contents of the bag were transferred back to a large cystallizing dish. Residual volatiles were removed by first putting under pump vacuum overnight and then in a 150° C. vacuum oven for 73 hours. The product consisting largely of yellow granules, weighed 261 g for a weight gain of 20% and combustion analysis found 12.33 wt % fluorine or 16 wt % PTFE in rough agreement with the measured weight gain.
Example 6
Polymerization of PTFE in Porous Poly(P-Phenylene Terephthalamide) Fibers
Never dried poly(p-phenylene terephthalamide) fibers, containing 30% to 70% by weight water, was first made ready for TFE polymerization by replacing the water in its pores with a solvent suitable for fluoroolefin polymerization. Thirty-five grams of never dried poly(p-phenylene terephthalamide) fibers were mixed in ajar with 50 ml of trifluoroacetic acid. After standing overnight, the contents of the jar were washed into a chromatography column using additional trifluoroacetic acid. Excess trifluoroacetic acid was drained off. Fifty ml of fresh trifluoroacetic acid were added to the top of the column and excess fluid again drained off, leaving the liquid level in the column about 3 cm above the poly(p-phenylene terephthalamide) layer. Over the following days, the poly(p-phenylene terephthalamide) in the chromatography column was washed in turn with 50 ml trifluoroacetic acid, 50 ml of Freon® E1 (CF 3 CF 2 CF 2 OCFHCF 3 ), 50 ml Freon® E1, 50 ml Freon® E1, and 50 ml of chilled ˜0.03 M DP in Freon® E1. The cold DP solution was drained through the poly(p-phenylene terephthalamide) as rapidly as possible while low pressure nitrogen was applied to the top of the column towards the end for the purpose of expelling most unabsorbed fluid. In this operation the nitrogen flow was stopped before drying out of the poly(p-phenylene terephthalamide) particulates occurred. The poly(p-phenylene terephthalamide) having DP initiator in its pores was chilled on dry ice and transferred to a 400 ml autoclave pre-chilled to less than −20° C. The autoclave was evacuated and 25 g of TFE was added, raising pressure to ˜78 psi at −43° C. After shaking overnight at room temperature, pressure in the autoclave had decreased to 7 psi. Upon recovery and drying under pump vacuum, the poly(p-phenylene terephthalamide) weighed 38.3 g. The appearance of the composition after recovery was a mix of free flowing particulates and agglomerated particulates, and was cream colored. The poly(p-phenylene terephthalamide) was yellow in color prior to TFE polymerization. Examination by optical microscopy under cross polarizers showed bright, irregularly-shaped poly(p-phenylene terephthalamide) particles with dark PTFE deposits filling most of the pores. Little PTFE was visible at the surface of the poly(p-phenylene terephthalamide) particles. Most often, the dark PTFE areas were 50 microns to 200 microns in diameter. Combustion analysis of one of the agglomerated chunks showed 57.1% fluorine by weight.
Example 7
Porous Poly(M-Phenylene Isophthalamide) Powder, Atmospheric Pressure TFE Polymerization
A. Intermediate PTFE Loading
Porous poly(m-phenylene isophthalamide) [MPD-I] particulates were prepared by precipitating MPD-I solution (in dimethylacetamide/CaCl 2 ) in water, washing with water and drying in vacuum at 100° C. A 4.83 g sample of these poly(m-phenylene isophthalamide) particulates was soaked at −15° C. in 40 ml of CF 2 ClCCl 2 F containing 1.0 ml 0.16 M HFPO dimer peroxide in Vertrel™ XF. After 15 minutes, the poly(m-phenylene isophthalamide) was separated by vacuum filtration, stopping filtration as soon as the liquid flow seemed near an end. The poly(m-phenylene isophthalamide), still damp with initiator solution, was transferred to a 6×9 ″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was evacuated and filled 3× with N 2 and 3× with TFE. The bag was inflated a final time with TFE and the polymerization allowed to run at room temperature. Most of the TFE reacted over the next 2.5 hours as seen in the near total deflation of the bag. The contents of the bag were poured out. After ˜64 hours under pump vacuum, the product weighed 7.50 g (153% of starting weight) and consisted largely of white lumps not much different in visual appearance than at the start. Combustion analysis found 12.8 wt % fluorine.
B. Higher PTFE Loading
Porous poly(m-phenylene isophthalamide) [MPD-I] particulates were prepared by precipitating MPD-I solution (in dimethylacetamide/CaCl 2 ) in water, washing with water and drying in vacuum at 100° C. A 6.5 g sample of these poly(m-phenylene isophthalamide) particulates was soaked at −15° C. in 50 ml of 0.18 M HFPO dimer peroxide in Vertrel™ XF. After 15 minutes, the poly(m-phenylene isophthalamide) was separated by vacuum filtration, stopping filtration as soon as the liquid flow seemed near an end. The poly(m-phenylene isophthalamide), still damp with initiator solution, was transferred to a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was evacuated and filled 3× with N 2 and 3× with TFE. The bag was inflated a final time with TFE and the polymerization allowed to run at room temperature. Over the next 3 hours the bag deflated and was refilled with TFE five times. The contents of the bag were poured out. After four days under pump vacuum, the product weighed 20.5 g (315% of starting weight) and consisted largely of white lumps not much different in visual appearance than at the start. Combustion analysis found 48.7 wt % fluorine.
Example 8
Porous Poly(M-Phenylene Isophthalamide) Fibrids, Atmospheric Pressure TFE Polymerization
A. Intermediate PTFE Loading
Porous [poly(m-phenylene isophthalamide)] fibrids were prepared by precipitating MPD-I solution (in dimethylacetamide/CaCl 2 ) in water under shear, washing with water and drying in vacuum at 100° C. A 6.52 g sample of these poly(m-phenylene isophthalamide) fibrids was soaked at −15° C. in 40 ml of CF 2 ClCCl 2 F containing 1.0 ml 0.16 M HFPO dimer peroxide in Vertrel™ XF. After 15 minutes, the poly(m-phenylene isophthalamide) was separated by vacuum filtration, stopping filtration as soon as the liquid flow seemed near an end. The poly(m-henylene isophthalamide), still damp with initiator solution, was transferred to a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was evacuated and filled 3× with N 2 and 3× with TFE. The bag was inflated a final time with TFE and the polymerization allowed to run at room temperature. Most of the TFE reacted over the next 1.5 hours as seen in the near total deflation of the bag. The contents of the bag were poured out. After a weekend under pump vacuum, the product weighed 9.84 g (151% of starting weight) and consisted largely of flat white clumps of fibrids not much different in visual appearance than at the start. Combustion analysis found 40.5 wt % fluorine.
B. Higher PTFE Loading
Porous poly(m-phenylene isophthalamide) [MPD-I] particulates were prepared by precipitating MPD-I solution (in dimethylacetamide/CaCl 2 ) in water, washing with water and drying in vacuum at 100° C. A 6.5 g sample of these poly(m-phenylene isophthalamide) particulates was soaked at −15° C. in 50 ml of 0.18 M HFPO dimer peroxide in Vertrel® XF. After 15 minutes, the poly(m-phenylene isophthalamide) was separated by vacuum filtration, stopping filtration as soon as the liquid flow seemed near an end. The poly(m-phenylene isophthalamide), still damp with initiator solution, was transferred to a 6×9″ ziplock polyethylene bag equipped with a gas inlet valve. The bag was evacuated and filled 3× with N 2 and 3× with TFE. The bag was inflated a final time with TFE and the polymerization allowed to run at room temperature. Over the next 3 hours the bag deflated and was refilled with TFE five times. The contents of the bag were poured out. After four days under pump vacuum, the product weighed 18.1 g (278% of starting weight) and consisted largely of flat white clumps of particulates not much different in visual appearance than at the start. Combustion analysis found 55.3 wt % fluorine.
Example 9
Ultrasuede®, Atmospheric Pressure TFE Polymerization
A rectangular sample of blue Ultrasuede® (a leather mimic believed to be a foamed polyurethane) weighing 2.1 g and measuring 7.6 cm×8.2 cm×0.09 cm thick, was immersed in a ˜0.16 M solution of DP in Vertre® XF maintained at −15° C. After 15 minutes, the Ultrasuede® was removed from the initiator solution and excess fluid allowed to drain for five or 10 seconds. The Ultrasuede® still wet with absorbed initiator was transferred to a 6×9″ ziplock polyethylene bag provided with a gas inlet valve. The bag was sealed, evacuated and inflated 3× with N 2 and 3× with TFE. The bag was inflated a fouth time with TFE. Using an exterior clamp, all but a corner of the Ultrasuede® sample was held away from contact with the walls of the bag. The Ultrasuede® was recovered 23 hours later and devolatilized for 3 days under pump vacuum. While unchanged in appearance, the Ultrasuede® weighed 2.4 g, ˜14% more than at the start. Combustion analysis found 6.00 wt % fluorine. A drop of distilled water placed on either side of the Ultrasuede® sample treated here took ˜46 minutes to show initial wetting and never soaked into the Ultrasuede® prior to evaporation. For comparison purposes, an untreated Ultrasuede® sample was found to completely absorb a drop of water within about one minute on one side and to not be wetted at all by water on the reverse side (combustion analysis found 0.14 wt % F on the starting Ultrasuede® suggesting a fluorinated finish at the start).
Example 10
Pigskin and Cowskin
A 5-cm square of commercial beige pigskin purchased at retail (chrome tanned split, one side suede, reverse side rough) weighing 1.69 g and measuring ˜0.15 cm thick was immersed in a ˜0.16 M solution of DP in Vertrel® XF maintained at −15° C. A 5 cm square of commercial black cowhide purchased at retail (chrome tanned split, suede both sides) weighing 2.09 g and measuring ˜0.12 cm thick was immersed in a ˜0.16 M solution of DP in Vertrel® XF maintained at −15° C. After 60 minutes, the two leather samples were removed from the initiator solution and excess fluid allowed to drain for five or 10 seconds. The leather samples still wet with absorbed initiator were transferred to a 6×9″ ziplock polyethylene bag provided with a gas inlet valve. The bag was sealed, evacuated and inflated 3× with N 2 and 3× with TFE. The bag was inflated a fourth time and the bag and its contents tumbled overnight at room temperature. After recovery, the leather samples were devolatilized to constant weight under pump vacuum. The pigskin, slightly darkened in appearance, now weighed 1.86 g for a 10% weight gain and analysed for 9.56 wt % F by combustion analysis. While unchanged in appearance, the cowskin weighed 2.25 g for a 5% weight gain and analyzed for 9.15 wt % F by combustion analysis. It should be noted that the starting pigskin and cowhide samples analyzed for 1.77 and 0.39 wt % F before the treatment described here.
Example 11
Liquid Phase Perfluoromonomer
A. In Wood Under Inert Atmosphere
A jar was chilled to about −15° C. and 25 ml of PMD and 2 ml of ˜0.16 M DP in CF 3 CF 2 CFHCFHCF 3 solvent were added. A cube of redwood ˜1.9 cm on a side weighing 2.46 g was immersed in the solution contained in the jar for about 1 hour at −15° C. The redwood cube was removed, allowed to drain and then transferred to a 20.32 cm×25.4 cm zip lock polyethylene bag (Brandywine Bag Co., part number 301630) equipped with a polypropylene gas inlet valve. The bag was clamped shut, inflated and evacuated 3 times with nitrogen, and allowed to sit over the weekend. The cube was removed and a few pieces of white polymer rubbed off its surface with a spatula. After devolatilizing for 9 days under pump vacuum at room temperature, the cube weighed 4.45 g for a 81% weight gain. One side of the cube was lightly sanded revealing an attractive brown surface slightly darker in appearance. A drop of water placed on the surface remained there for about two hours until it evaporated. A drop of water placed on an untreated redwood cube wet the surface within a minute and took about 30 minutes to soak into the cube, having spread out into a visibly large wet area on the cube.
B. In Wood Under TFE Atmosphere
A cube of redwood, ˜1.9 cm on a side and weighing 2.27 g was immersed in the PMD/DP solution left over from part B of this Example for 1 hour at −15° C. The redwood cube was removed, allowed to drain and then transferred to a 20.32 cm×25.4 cm zip lock polyethylene bag (Brandywine Bag Co., part number 301630) equipped with a polypropylene gas inlet valve. The bag was clamped shut, inflated and evacuated three times with nitrogen, inflated and evacuated three times with TFE, loosely inflated with TFE, and allowed to sit over a three days. The cube was removed along with 2.9 g of PTFE. Most of the PTFE removed was loose but some of it was scraped off of the redwood cube. After devolatilizing for 9 days under pump vacuum at room temperature, the cube weighed 4.51 g for a 99 percent weight gain. One side of the cube was light sanded revealing an attractive silvery brown surface darker in appearance than at the start. A drop of water placed on the surface remained on the surface of the cube for about two hours until it evaporated. A drop of water placed on an untreated redwood cube wet the surface of the cube within a minute and took about 30 minutes to soak into the cube, having spread out into a visibly large wet area on the cube. | The present invention relates to in situ polymerization of fluoropolymer into porous substrates, to improve resistance to wear, tear and creep, decay, and degradation by wetting, staining and warping, and to improve durability while maintaining the appearance of the substrate. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to apparatus for, and a method of, heating heat-recoverable articles, and more particularly to such apparatus and such a method for effecting recovery of heat-shrinkable cable closures.
2. Related Art
Heat-recoverable sleeving is often used to protect joins in electrically conducting cables and in optical fiber signalling lines. In use, a sleeve is passed over one end of a cable, for example a cable having multiple pairs of signalling wires and, once jointing of one cable to another cable has been completed, the sleeve is relocated over the joint area, the sleeve spanning the ends of the respective insulating jackets of the cables. Alternatively, after the joint has been formed, a split sleeve is positioned over the jointing area, and is sealed using a hot melt adhesive or other heat-activated sealing material. Heating the sleeve causes it to shrink and grip tightly around the cable jacket and the joint area, thereby effecting water resistance and insulation. Care must be taken during the shrinking operation to ensure that air entrapment is limited.
Thus, for example, if the ends of a sleeve are recovered too rapidly, so that sealing of the sleeve to the insulating cable jackets prevents air from escaping, then the central portion of the sleeve may be prevented from shrinking fully onto the joint area by the entrapped air. Accordingly, skilled operators are employed to effect the shrinking operation, usually by applying a gas torch to the sleeve area, and moving the torch from the center towards the ends.
However, as will be appreciated, many such jointing operations are performed in restricted areas, such as in underground cable chambers, where the effects of combustion products may be dangerous to the operator. Furthermore, the use of a naked flame in such chambers, in which a build up of combustible or explosive gases is possible, should preferably be avoided.
One solution to the above problem has been disclosed in U.S. Pat. No. 5,030,810 which has been made by the present patent. In the aforementioned application, there is disclosed a portable heating device comprising a body forming an elongate enclosure, the interior of which has independently-energizable electrical heating elements, whereby the longitudinal temperature profile within the enclosure, may be controlled. The body comprises two half cylinders hinged on one side. Thus, by placing a sleeved joint in the elongate body, and then energizing the heating elements, the central portion reaches recovery temperature very quickly, while the outer portions reach that temperature more gradually.
It has been found using the heating device disclosed in U.S. Pat. No. 5,030,810 that the quality of the insulation and water resistance of the joint after shrinkage of the heat recoverable sleeve is affected by the temperature inside the enclosure at the time the heating device commences operation. In particular, it has been found that the heating device may produce sleeved joints of poor insulation and water resistance at commencement temperatures below zero degrees fahrenheit.
BRIEF SUMMARY OF THE INVENTION
The aim of the invention is to provide apparatus for, and a method of, effecting recovery of a heat-shrinkable article in a controllable manner to produce sleeved joints of uniform quality.
The present invention provides apparatus for applying heat to heat-recoverable articles, the apparatus comprising a heating device, a plurality of independently-energizable electrical heating elements within the heating device, at least one sensor for sensing the actual temperature within the heating device, and a control circuit connected to the heating elements and to the or each sensor, the control circuit being capable of independently energizing the heating elements and, by using the or each sensor, detecting the actual temperature within the heating device, whereby the control circuit heats the heating device using a uniform or near uniform temperature profile within the heating device until a pre-set temperature is reached within the heating device, and subsequently heats the heating device using a non-uniform temperature profile within the heating device for a period of time sufficient to cause heat recovery.
The invention also provides apparatus for applying heat to heat-recoverable articles, the apparatus comprising a heating device with an interior containing a plurality of independently-energizable electrical heating elements, at least one temperature sensor within the heating device for sensing the internal temperature of the heating device, and a control circuit connected to the heating elements and to the or each sensor for measuring the initial temperature of the heating device and selecting a heating profile dependent thereon to effect heat recovery.
Preferably the heating device has a cylindrical body, and comprises two half cylinders hinged on one side to simplify access to the interior of the heating device.
The body of the heating device may have removable end plates which include apertures through which one or more cables and one or more heat-recoverable articles may pass. The end plates may be relocated to reduce the size of the interior of the body of the heating device, which may also include in its interior one or more support plates and/or thermal baffles.
The control circuit may produce the temperature profile within the interior of the heating device by sequential energization. The energization sequence may have a predetermined time interval between each step thereof or the energization sequence may be related to the actual temperature profile within the body of the heating device.
The control circuit may be arranged to cause energization of the heating elements closest to the center of the heat-recoverable article prior to energization of heating elements away from the center of the heat recoverable article.
The invention further provides a method of applying heat to a heat-recoverable article in apparatus which comprises a body the interior of which has a plurality of independently-energizable electrical heating elements and means for sensing and indicating the actual temperature within the body, the method comprising the steps of placing the heat-recoverable article together with a joint or joints to be covered within the body, energizing the heating elements to produce a uniform or near uniform temperature profile within the body until a pre-set temperature is indicated, and energizing the heating elements to produce a non-uniform temperature profile within the body for a period of time.
The invention also provides a method of applying heat to a heat-recoverable article in apparatus having an interior with a plurality of independently-energizable electrical heating elements and temperature sensing means, the method comprising the steps of placing the heat-recoverable article together with a joint or joints to be covered within the apparatus, sensing the internal temperature of the apparatus, and selecting a heating profile dependent on the sensed temperature to effect heat recovery.
BRIEF DESCRIPTION OF THE DRAWINGS
Apparatus constructed in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is an isometric view of a heating device for effecting shrinkage of a heat recoverable cable joint sleeve,
FIG. 2 is a schematic diagram indicating the apparatus used to control the temperature of the heating device, and
FIG. 3 is a flow diagram indicating the operation of the apparatus.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Referring to FIG. 1 the heating device comprises a housing in the form of two half cylinders 1 of thermally insulating material. The two half cylinders 1 are linked together by "lift-off" hinges 2 on one edge and have the respective halves of clamp arrangements 3 of known kind on the opposed edges. Thus the two half cylinders 1 may in use be locked together using the clamps 3 to form a cylindrical oven enclosure.
Embedded in the walls of the body of the heating device a number of groups of electric heating elements 4 to 7 (only some of which are shown) are provided, each having an individual connection wire (not shown) for power to be supplied from a controller. Between each group of heating elements 4 to 7, and at each end of the half cylinders, mounting guides 8, 9 may be provided to which end plates 10 may be fitted.
Each end plate 10 includes one or more semicircular grooves 10 arranged on closure of the cylinder to form an aperture. The grooves 11 each carry a support plate 12 which, in use, provides support to the ends of a jointed cable (not shown). Several pairs of interchangeable end plates may be provided to cater for different cable sizes. For example the end plates 10 are adapted for use with a single cable of a larger diameter while the end plates 10' take a similar cable and a smaller cable.
Other exemplary end plates for a single smaller diameter cable, three such cables and a cable of intermediate diameter are also shown at 10'.
For the avoidance of doubt the term cables as used herein includes not only multi cored electrical signalling cables but also cables comprising of multiple optical fibers co-axial cables and the like.
The interior of the half cylinder shells 1 comprises a heat radiating surface 14 which is preferably coated with a "non-stick" material such as Teflon (trademark) to facilitate the removal of (e.g.) hot melt adhesives which may have been used in the jointing process.
As shown in the diagram, adjacent the groups of heating elements 4 nearest the longitudinal center of the enclosure a further pair of plates 15 are provided. The plates 15 have two functions the first of which is to give support to a cable when it is in the enclosure and the second of which is to act as a thermal baffle to prevent premature temperature rises along the length of the cylinder.
It will be realized that, as with the end plates 10, the plates 15 may be located in different positions along the length of the half cylinders 2 either using the same mountings 8 or additional mountings (not shown). It will also be appreciated that the plates 15 may carry extensions similar to the shells 12 to provide additional longitudinal support.
To enable the control of the temperature profile along the length of the enclosure one or more thermocouples 16 are incorporated in the walls of the shells 1 as thermal sensors.
Referring to FIG. 2 the sensor 16 and heating elements 4, 5, 6 and 7 perform the functions as previously described and are connected to a first control circuit 17 and a second control circuit 18.
If the temperature sensed by sensor 16 within the body (internal temperature) is below the trigger temperature the first control circuit 17 energises the heating elements 4, 5, 6 and 7 to produce a uniform or near uniform temperature profile within the body (the pre-heat cycle) until the internal temperature reaches a pre-set temperature (the pre-set temperature). If the internal temperature is at or above the trigger temperature the first control circuit 17 will wait until the internal temperature falls below the trigger temperature before energizing, in the mode referred to above (i.e. the pre-heat cycle) the heating elements 4, 5, 6 and 7. A typical trigger temperature is 30° Centigrade and a typical pre-set temperature is 40° Centigrade.
Upon completion of the pre-heat cycle, the second control circuit 18 will energize the heating elements 4, 5, 6 and 7 to produce a non-uniform temperature profile within the body (the shrinkage cycle) to ensure shrinkage of the recoverable sleeve within the heating device occurs without trapping air within the sleeve (as discussed above).
In use, where two or more cables are to be joined a suitable heat recoverable sleeve is selected and placed over one of the cables. Once jointing or splicing of the cables is completed, the joint area or the inside of the sleeve may be coated with a hot melt adhesive if required and the sleeve positioned thereover. Alternatively a split sleeve pre-coated with hot melt adhesive is selected and wrapped over the joint area after completion of splicing or jointing.
Suitable end plates 10 are selected and placed in respective mountings 8, 9 in dependence upon the length of the joint to be sealed together with the intermediate support/thermal baffle plates 15 as necessary. The two half shells 1 are then positioned so that the jointed cables rest in the supports 12 and the enclosure is closed and locked together using the clamps 3. Connection leads from the heating elements 4 to 7 and the thermal sensor(s) 16 may now be connected to the controller. The operator provides the joint parameters on the controller, for example the type and length of joint, the kind of sleeving in use and starts the sequence.
Referring to FIGS. 2 and 3, the first control circuit 17 and the second control circuit 18 which may be conveniently provided by using custom built Programmed Logic Control or a microprocessor, now steps through the following predetermined sequences releasing the operator to perform other tasks. In FIG. 3, T=Internal Temperature; T t =Trigger Temperature; T p =Preset Temperature; F=Either time or temperature; and F n =Either respectively a predetermined time or a predetermined temperature.
In a typical sequence, a signal is sent to the first control circuit 17 instructing it to initiate energization of the heating device (the commence pre-heat signal). Using sensor 16, the first control circuit 17 senses the internal temperature and if the internal temperature is below the trigger temperature the first control 17 circuit initiates the pre-heat cycle.
During the pre-heat cycle the first control circuit 17 energizes the heating elements 4, 5, 6 and 7 either in a sequence or randomly to avoid overloading the power supply, which may be conveniently a battery or a generator, to produce a uniform or near uniform internal temperature until the internal temperatures reaches the pre-set temperature. When the internal temperature reaches the pre-set temperature, the first control circuit 17 ceases energization of the heating elements 4, 5, 6 and 7 and sends a signal to the second control circuit 18 to carry out the shrinkage cycle (the commence shrinkage signal). If on receipt of the commerce pre-set signal, the internal temperature is at or above the trigger temperature, then, the first control circuit 17 will monitor the internal temperature using sensor 16 and wait until the temperature is below the trigger temperature before carrying out the pre-heat cycle and subsequently sending the commence shrinkage signal as described above.
Once the commence shrinkage signal has been received by the second control circuit 18, the second control circuit 18 commences the shrinkage cycle.
In a typical shrinkage cycle the second control circuit 18 first causes the two groups of elements 4 closest to the centre of the enclosure to be energized for a short period of time which may be either a predetermined period (say five minutes) or may be until a given temperature as sensed by sensor 16 is reached.
This initial heating of the central area of the joint ensures that shrinkage if that portion of the recoverable sleeve occurs before any likelihood of the sleeve sealing to the insulated sleeving of the cables thereby allowing entrapped air to escape.
In the next step of the shrinkage cycle, the second control circuit 18 causes the next to center groups of elements 5 to be energized again for a predetermined period or until a given temperature is sensed during which period the elements 4 may either remain energized or be turned off as required. The groups of elements 6 and 7 may then be energized in turn. It will be realized that a combination of the time and temperature factors may be used such that at each step mentioned above a predetermined period elapses after a given temperature is reached prior to proceeding to the next step.
While as herein described during the shrinkage cycle the heating elements 4, 5, 6 and 7 are controlled to heat a central area first progressing outwardly to the ends it will be appreciated that the longitudinal temperature profile of the enclosure may be controlled in any required manner. For example if sealing of one end is preferred prior to sealing of the opposed end then during the shrinkage cycle the second control circuit 18 may energize the heating elements in the order 7, 6, 5, 4 at one end of the enclosure followed by the corresponding heating elements in the order 4, 5, 6, 7 at the opposed end of the enclosure.
Further although the device has been described with reference to a preformed heat recoverable sleeve other thermally responsive mechanisms such as sheets of material wrapped around a joint may be used.
The control circuit could include a number of look up tables, for example, to allow different temperature profiles and equencing including a waiting period to be effected dependent on the initial measured internal device temperature for example. | A device and a method for shrinking heat recoverable sleeves for covering cable joints comprising a heating device the interior of which has a plurality of independently energizable heating elements and at least one sensor and a control circuit or control circuits which are connected to the heating elements and the at least one sensor. The control circuit is arranged to produce a uniform and then a non-uniform temperature profile within the heating device unless the initial temperature within the heating device is above a given temperature (e.g.) 30° C. in which case the control circuit waits until the temperature within the heating device falls to below the given temperature before producing the temperature profiles whereby sleeved cable joints of a uniform quality are produced by avoiding air entrapment within the sleeve during the shrinking process. | 1 |
TECHNICAL FIELD
The invention relates to generally to serial printers, and more specifically to media handling mechanisms for swath-oriented printers such as inkjet printers.
BACKGROUND OF THE INVENTION
Inkjet style printers typically utilize one or more pens held in a carriage that moves across the paper from side-to-side, with each pen having multiple nozzles organized as a vertical array, and an advance or "slew" mechanism, for advancing a sheet of paper (or other appropriate ink-receiving medium) beneath the pen (i.e., from top to bottom). Thus the advance mechanism moves the paper to the proper line, and the inkjet pen then moves laterally across the paper into position to print a band or swath whose height is limited by the vertical dimension of the nozzle array, and whose width is determined by the corresponding dimension of the sheet. After the selected nozzles are "fired," creating a single column of dots ("pixels") of ink, the pen continues in its lateral movement across the width of the sheet until it reaches the position where the next dot of ink is required. To avoid pixels "running together" ink may be applied to adjacent pixels in separate passes, allowing the first to at least partly dry before the second or subsequent pixels are created. Once the current swath is completed, the advance mechanism moves the page such that the lateral path of the pen is lower in the page and the process is repeated until the page is printed.
The known prior art designs require that the printer housing be large enough to accommodate the lateral movement of the pen, thereby establishing minimum dimensions for both the volume and the "footprint" (e.g the area occupied by the cabinet). Furthermore, multi-lead flexible cables typically provide power and control signals to the moving pen from a fixed power supply and control circuitry inside the housing, adding to the cost and complexity of the printer and potentially resulting in undesirable radio frequency interference. Also, the moving pen must either be connected to a remote reservoir of ink (thereby adding further cost and complexity) or the pen must contain a built-in ink reservoir (which increases the moving mass and therefore consumes additional power). Space and power consumption are of particular concern for portable applications, as a smaller and less costly device is understandably preferred.
SUMMARY OF THE INVENTION
The present invention provides a device for printing with an inkjet style pen in which the pen remains stationary relative to a housing, while a paper is moved on two axes under the pen, and the paper can move outside of the housing to keep the volume and footprint of the housing to a minimum. A tracking system is also provided to insure that printing takes place in the correct portion of the paper.
In a first embodiment, the present invention provides a printer for printing an image on a sheet of a print medium, the print medium having an image surface on which the image may be formed, the printer comprising a housing, at least one pen having a tip responsive to a first control signal for forming at least one image pixel on an adjacent pixel location of the image surface, a pen holder for holding said pen inside the housing with said tip in a fixed position relative to the housing, a print medium holder at least partially inside the housing for movably holding said medium with different portions of said surface adjacent said tip, at least one motor responsive to a second control signal and mechanically coupled to the print medium holder for moving said medium on two orthogonal axes relative to said tip; and a controller coupled to said pen and to said motor for supplying said first and second control signals to thereby form said image.
In other embodiments, the present invention provides a printer wherein the stationary pen is an ink jet style pen with an array of nozzle jets arranged to print a swath of pixels perpendicular to the slew axis; the print medium extends outside the housing in the direction of the slew axis, the nozzle array is perpendicular to the slew axis, a reservoir portion of the ink jet pen has a minor axis parallel to the slew axis, and a maximum travel along the slew axis is greater than a corresponding maximum along the minor axis; said at least one motor is maintained in a stationary position relative to said housing; said at least one motor, said controller and said pen holder are contained completely inside the housing; the at least one motor further comprises two motors, a swath motor and a slew motor, each having separate tracking means for tracking the position of the paper relative to the pen; the tracking means comprises a swath tracking surface, which is interconnected to the swath motor and has readable positioning marks, a swath sensor for reading the readable positioning marks and transmitting such to the controller, a slew tracking surface, which is interconnected to the slew motor and has readable positioning marks, and a slew sensor for reading the readable positioning marks and transmitting such to the controller; the print medium holder further comprises a paper holding crimp securing a removable edge of the print medium or the print medium holder further comprises at least one set of opposing rollers, said rollers being pivotally mounted to the case.
These and other features and advantages of this invention will become further apparent from the detailed description and accompanying figures that follow. In the figures and description, numerals indicate the various features of the invention, like numerals referring to like features throughout both the drawings and the description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of the interior of a preferred embodiment of the present invention.
FIG. 2 is a side isometric view of the advance mechanism a preferred embodiment of the present invention.
FIG. 3 is an isometric view of the pen and the advance motor and mechanism of FIG. 2.
FIG. 4 is an isometric view of the swath mechanism of a preferred embodiment of the present invention.
FIG. 5 is a side elevational view of the swath axis of a preferred embodiment of the present invention.
DETAILED DESCRIPTION
FIG. 1 shows a stationary pen printer 10 constructed according to the present invention. A housing 12 includes a pen 14 for printing on a print medium, such as, in a preferred embodiment, a piece of paper 22, said pen 14 being mounted in a stationary relationship to the housing 12 and contained a predetermined distance from the paper 22 by a pen holder (not shown) such as the pen holder described in U.S. Pat. No. 5,392,063. The stationary pen printer 10 can use a commercially available pen 14, such as the HP C1816A, a three color pen (other commercially available pens suitable for use in the present invention range from four color pens to simple black and white units. The pen 14 has a nozzle mechanism 20 for expelling ink onto the paper 22. Typically, the pen is mounted perpendicular to the direction of print across a page. Because it is stationary, the pen 14 may be directly connected to the circuitry of the stationary pen printer 10 without the use of a flexible multi-lead cable (which would be required for a moving pen).
The housing 12 also has a paper holding means, which can take any number of forms, such as a set of opposing rollers or a pallet supporting the underside of the paper. In a preferred embodiment, it includes a paper guide strip 16, which has on one side a paper holding crimp 18 for holding the paper 22 which may have a removable border edge (not shown) to allow printing on the entire surface of the paper 22. Mechanisms automatically feeding paper from a stack may also be employed. The housing 12 has a gap 15 between a nozzle mechanism 20 end of the pen 14 and the housing 12, which extends laterally to enclose the paper guide strip 16, allowing all parts to the paper 22 to move beneath the nozzle mechanism 20 with parts of the paper 22 and paper guide strip 16 extending outside the housing 12. This movement of the paper 22 outside the housing 12 significantly reduces the required size and footprint of the housing 12, as it does not have to be large enough to enclose the entire paper 22, as do prior art devices (which also have to provide even more room within their cases to allow for the dimensions of the pen on both ends of the paper). Referring to FIGS. 1, 2 and 3, also mounted to the housing 12 is a "swath" or advance mechanism 24 for moving the paper guide strip 16 (and thus the paper 22) in the direction shown by the arrows in FIGS. 2 and 3 (i.e., the paper guide strip 16 moving towards and away from the pen 14). Although different embodiments may print on this, the advance axis of movement, or on both the advance axis and the slew axis (discussed below), in a preferred embodiment the printing is done only during the slew axis, as fully described below (an advance axis may be compared to the carriage return in a mechanical typewriter, and the slew axis to the cross-wise movement during the typing process).
The advance mechanism 24 includes a motor means, which can take any of a number of forms, such as a single motor powering movement in both the advance axis and the slew axis (see below), or separate motors powering each axis. In a preferred embodiment, the advance mechanism 24 has a dedicated motor, such as advance motor 26 which is connected to a threaded shaft 28 via one or more gears, such as gear 32, gear 34 and gear 36. The threaded shaft 28 is connected to gear 36 at one end, passes through a threaded spring loaded nut 38 and is connected at its other end to an advance code wheel 40. The threaded spring loaded nut 38 surrounds the threaded shaft 28 and forms a cavity 42 though which a paper advance flange 44 of a paper carriage 46 passes. The paper carriage 46 also includes an upper surface 48 for supporting a portion of the paper 22, and a preloaded plastic bushing system 50, located beneath the paper carriage 46. The preloaded plastic bushing system 50 includes one or more wheels, such as wheel 52 and wheel 54 and corresponding and opposing plastic bushings, such as plastic bushing 56 and plastic bushing 58. Located between wheel 52 and plastic bushing 56, and between wheel 54 and plastic bushing 58 is a rigid guide way 62. A spring 64 urges wheel 52 and wheel 54 against the rigid guide way 62 which is thus secured between wheel 52 and wheel 54 on the one hand, and plastic bushing 56 and plastic bushing 58 on the other hand.
The advance mechanism 24 also includes a code and sensor means for locating the exact position of the paper guide strip 16. The code and sensor means can take any number of forms, such as magnetic codes, tactile markings or optical codes, perhaps located on a stationary part, such as rigid guide way 62, and a sensor located on a moving part, such as the paper carriage paper carriage 46. In a preferred embodiment, a stationary advance optical sensor 66 for reading the codes on the advance code wheel 40 and transmitting that information electronically to a controller means 68 (FIG. 1) is provided.
The threaded spring loaded nut 38 and upper surface 48 form a recess 30 through which the paper guide strip 16 passes, such that movement of the threaded spring loaded nut 38 and the upper surface 48 in the direction of the advance axis (see arrows on FIGS. 2 and 3) will cause the paper guide strip 16 to be pulled by the recess 30 in the same direction, and to move relative to the pen 14 but not to the threaded spring loaded nut 38 and upper surface 48. However, as discussed below, the paper guide strip 16 may pass through the recess 30 back and forth in the direction of the slew axis (see arrows on FIG. 4).
Thus the advance mechanism 24 moves the paper 22 in the following manner. The controller means 68 senses the position of the paper guide strip 16 and the paper 22 along the advance axis by the position signal from the advance optical sensor 66, and determines in which direction the advance mechanism 24 should advance the paper 22. The controller means 68 then sends a control signal to the advance motor 26 which turns the threaded shaft 28 via gears, such as gear 32, gear 34 and gear 36. The threaded shaft 28 in turn rotates through the threaded spring loaded nut 38, and the threads of the threaded shaft 28 engage the threads of the threaded spring loaded nut 38 urging the threaded spring loaded nut 38 laterally along the length of the threaded shaft 28, the direction depending upon the rotational direction of the advance motor 26.
Referring to FIGS. 4 and 5, a slew mechanism 72 is provided for moving the paper guide strip 16 (and thus the paper 22) in the direction shown by the arrows in FIG. 4 (i.e., the paper guide strip 16 moving back and forth while maintaining a constant distance from the pen 14). As noted above, in different embodiments printing may occur during the advance axis of movement, the slew axis of movement, or both. However, in a preferred embodiment the printing is done only during the slew axis.
The slew mechanism 72 includes a motor means, which can take any of a number of forms, such as a single motor powering movement in both the advance axis and the slew axis, or separate motors powering each axis. In a preferred embodiment, the slew mechanism 72 has a dedicated motor, such as slew motor 74, which is connected to a transmission shaft 76 via a series of gears (or rollers), such as gear 78, gear 82, gear 84 and gear 86. The slew mechanism 72 is connected to the housing 12 (shown in relief). A guide shaft 88 is mounted to the housing 12, and passes through a sliding gear assembly 90. The sliding gear assembly 90 includes a driven gear 92, a gear 94, and a stabilizing gear 96.
The slew mechanism 72 also includes a code and sensor means for locating the exact position of the paper guide strip 16. As with the code and sensor means of the advance mechanism 24, the slew mechanism code and sensor means can take any number of forms, such as magnetic codes, tactile markings or optical codes, perhaps located on paper guide strip 16, and a sensor located on the sliding gear assembly 90. In a preferred embodiment, a slew optical sensor 102 for reading the codes on a slew code wheel 98 and transmitting that information electronically to a controller means 68 (FIG. 1) is provided.
The sliding gear assembly 90 moves the paper guide strip 16 and the paper 22 in the direction shown by the arrows on FIG. 4. The slew motor 74 turns the transmission shaft 76 via gears, such as gear 78, gear 82, and gear 84. The transmission shaft 76 in turn rotates against and turns the gear 94 which in turn rotates the driven gear 92. The driven gear 92 rotates against and moves the underside of the paper guide strip 16 (and thus the paper 22), while the upperside of the paper guide strip 16 is restrained by the stabilizing gear 96. The driven gear 92 and the stabilizing gear 96 can be urged towards the paper guide strip 16 in any number of ways, such as having a spring (not shown). Thus the sliding gear assembly 90 moves the paper guide strip 16 inwards and outwards in the direction of the arrows on FIG. 4. At the same time, the slew optical sensor 102 senses the position of the paper guide strip 16 relative to the sliding gear assembly 90 by reading the marks on the slew code wheel 98, and transmits that position to the controller means (FIG. 1). The controller means 68 then sends a control signal to the slew mechanism 72 to appropriately move the paper guide strip paper guide strip 16 and the paper 22 by activating the slew motor 74, which will rotate the gear 78, gear 82, gear 84 and gear 86, which in turn rotates transmission shaft transmission shaft 76 which transmits such rotational movement to gear 94 which rotates driven gear 92, thus moving paper guide strip 16 and paper 22. The sliding gear assembly 90 will move with the paper guide strip 16 when the advance mechanism 24 moves the paper guide strip 16 towards the pen 14, with the gear 94 still transmitting rotational movement from the transmission shaft 76 to the driven gear 92.
In operation, the user will load paper 22 into the stationary pen printer 10. This may be done in any number of ways, such as an automatic paper feeding mechanism or manual feeding. The paper 22 may be secured to the stationary pen printer 10, also in a variety of ways, such as using a curved palette, utilizing thick paper, or in a preferred embodiment, the paper 22 is secured to the paper guide strip 16 by crimping an edge into the paper holding crimp 18. The stationary pen printer 10 is connected to a device transmitting an stored or "real time" digital image from an image generating device, such as a computer or camera (not shown), which will transmit an image to the stationary pen printer 10 according to established protocols. The controller means 68 receives inputs from the slew optical sensor 102 and the advance optical sensor 66 giving the location of the paper 22 on two axes, the advance axis (noted by the arrows on FIGS. 2 and 3), and the slew axis (noted by the arrows on FIG. 4). In response to such inputs and to the electronically stored image, the controller means 68 moves the paper into the proper position for printing, and prints the image, as follows. The controller means 68 determines the position of the paper based upon the signals from the advance optical sensor 66 and slew optical sensor 102. If the paper 22 is not in the proper position for the printing operation, the controller means 68 will first determine how much movement is required on both the advance and slew axes. In a preferred embodiment, if movement is required on both axes, the advance axis will be positioned first. The controller means 68 will order the advance motor 26 to rotate in the appropriate direction, which will turn gear 32, gear 34, and gear 36, which will rotate threaded shaft 28. Threaded shaft 28 will then urge threaded spring loaded nut 38 towards or away from the pen 14. Threaded spring loaded nut 38 urges the paper advance flange 44 and thus the paper carriage 46 in the same direction. Recess 30 surrounds the paper guide strip 16 and urges it also in that same direction, with the paper guide strip 16 perpendicular to the line of travel. The controller means 68 continuously monitors input from the advance optical sensor 66 and stops movement of the advance motor 26 when such input indicates that the paper guide strip 16 and paper 22 are in the proper position for printing. The controller means 68 then begins the printing process by making one or more printing passes on the slew axis by first positioning print media relative to the pen 14 by signaling the slew motor 74 to move the paper guide strip 16 into the proper position, and by monitoring that position via the slew code wheel 98 and the slew optical sensor 102. Once the paper guide strip 16 (and the paper 22) is in the proper position, the controller means 68 orders the pen 14 to print via its nozzle mechanism 20. Once the nozzle mechanism 20 is activated, the controller means 68 orders the slew motor 74 to move the paper guide strip 16 into the next position required for printing. Known techniques can be employed to maintain the paper 22 at an optimal distance from the nozzle mechanism 20, such as providing grids and stops in the vicinity of the nozzle mechanism 20, or by the inherent properties of the paper 22 (e.g., the thickness of the paper). When all printing on a given advance axis position is completed, the controller means 68 then moves the paper 22 on the advance axis, as described above, and the process repeats itself until an entire page is printed.
Having now described the invention in accordance with the requirements of the patent statutes, those skilled in the art will understand how to make changes and modifications in the present invention to meet their specific requirements or conditions. Such changes and modifications may be made without departing from the scope and spirit of the invention as set forth in the following claims. | A device for printing comprising a stationary inkjet-style pen, two stationary motors and a paper holder movable on two axes, a slew axis and an advance axis, wherein the paper is moved into the proper position for each step in the printing process by the paper holder and the two motors. | 1 |
BACKGROUND
[0001] During the lifespan of an oil reservoir, samples from the reservoir can be collected and analyzed. To effectively sample the production fluid from a well, and more particularly a subsea well, sampling systems are often located in close proximity to the wellhead. Wellhead sampling presents a challenge due to the potential for dispersed and mist flow from the wellhead containing both liquid and gas phases (multiphase flow). To take a liquid sample, the liquid phase must be separated from the gas phase. Multiphase flows exhibiting a dispersed or mist flow regime can be difficult to separate into component liquid and gas phase flows, in turn making the collection of liquid-only samples more difficult.
[0002] Further, sample systems may use a flow device, such as a venturi or an orifice plate, to generate a pressure differential proportional to the production flow. If the production flow rate is too low, the pressure differential generated by the flow device may be insufficient to retain a sample that contains both liquid and gas.
[0003] Further, multiple samples may be taken during the life of the well. Connecting and unconnecting equipment can be time consuming and servicing connections permanently mounted on the wellhead or other subsea structure can be difficult.
SUMMARY
[0004] An oil or gas well and related sampling assembly of this disclosure can be used to sample production fluids from the oil or gas well. The assembly includes a receiving structure that houses a saver sub, a retrievable skid, and protection plates. The receiving structure can be fixably attached to a manifold, an Xmas tree, or a length of pipe from which samples will be taken. The saver sub accesses the production flow via its connection with the receiving structure and then releasably connects with the retrievable skid. The receiving structure allows production fluid samples to be taken throughout the lifecycle of the manifold and the saver sub reduces the number of makes and breaks on the couplings in the manifold—instead, the interface between the retrievable skid and the saver sub is cycled with every sample taken. Among other valves and couplings, the retrievable skid houses the sample collection chambers.
[0005] Once the samples have been collected, a remotely operated vehicle (ROV) removes the retrievable skid and brings it to the surface. After the sample chambers are emptied and replaced, the sampling bottles are placed back in the retrievable skid, returned subsea, and reinstalled in the sampling system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] For a detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings in which:
[0007] FIG. 1 shows a perspective view of a receiving structure in accordance with various embodiments;
[0008] FIG. 2 shows a cross-sectional view of the saver sub interface on the receiving structure;
[0009] FIGS. 3 and 4 show perspective views of protection plates in accordance with various embodiments;
[0010] FIGS. 5 and 6 show perspective views of a saver sub in accordance with various embodiments;
[0011] FIG. 7 shows a bottom view of an embodiment of the multiple quick connect components on the saver sub that interface with the receiving structure;
[0012] FIG. 8 shows a top view of an embodiment of the multiple quick connect components on the saver sub that interface with the retrievable skid;
[0013] FIG. 9 shows a perspective view of the retrievable skid in accordance with various embodiments;
[0014] FIG. 10 shows a top view of an embodiment of the multiple quick connect components on the chassis plate of the retrievable skid that interface with the saver sub;
[0015] FIG. 11 shows a perspective view of the retrievable skid;
[0016] FIG. 12 shows a perspective view of a pump driven sampling assembly in accordance with various embodiments;
[0017] FIG. 13 shows an exploded view of a pump driven sampling assembly;
[0018] FIG. 14 shows an alternative embodiment of a pump driven sampling assembly; and
[0019] FIG. 15 shows a perspective view of an embodiment of a protection plate mounted on the receiving structure.
DETAILED DESCRIPTION
[0020] The following discussion is directed to various embodiments of the invention. The drawing figures are not necessarily to scale. Certain features of the embodiments may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in the interest of clarity and conciseness. Although one or more of these embodiments may be preferred, the embodiments disclosed should not be interpreted, or otherwise used, as limiting the scope of the disclosure, including the claims. It is to be fully recognized that the different teachings of the embodiments discussed below may be employed separately or in any suitable combination to produce desired results. In addition, one skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to intimate that the scope of the disclosure, including the claims, is limited to that embodiment.
[0021] Certain terms are used throughout the following description and claims to refer to particular features or components. As one skilled in the art will appreciate, different persons may refer to the same feature or component by different names. This document does not intend to distinguish between components or features that differ in name but not function.
[0022] In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the terms “couple,” “connect,” “engage,” and “attach” are intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices, components, and connections. The term “fluid” may refer to a liquid or gas and is not solely related to any particular type of fluid such as hydrocarbons. The term “pipe,” or the like refers to any fluid transmission means.
[0023] FIG. 1 shows the receiving structure 100 , comprised of a base platform 110 , a saver sub interface 130 , a plurality of posts 140 , and a sloped top structure 170 . The base platform 110 is generally rectangular but may be configured in any suitable shape. The posts 140 extend from and connect the base platform 110 to the sloped top structure 170 . The sloped top structure 170 includes sides that slope inward toward the center of the base platform 110 , creating upper perimeter 171 and lower perimeter 172 ; the upper perimeter being larger than the lower perimeter. In a preferred embodiment, the angle of the sloped top structure 170 is between thirty degrees and sixty degrees.
[0024] Two middle saver sub guides 155 extend from the surface of the base platform 110 . The middle saver sub guides 155 bend outward toward the lower rectangular perimeter 172 such that the upper portion of the middle saver sub guides 155 is angular and disposed on the lower rectangular perimeter 172 . Two corner saver sub guides 150 are disposed on the surface of the raised platform 120 . Two corner retrievable skid guides 160 are disposed on the surface of the base platform 110 . Each of the four corner guides (2—saver sub guides 150 , 2—retrievable skid guides 160 ) are made up of two middle saver sub guides 155 positioned orthogonally next to each other such that the lower portions of the guides contact each other, forming an “L” shape. A triangular web 158 bridges the gap between the top angular portions of the guides. The top portions of the corner guides 150 , 160 bend outward toward the lower rectangular perimeter 172 such that the triangular web 158 and upper portion of guides 150 , 160 are angular and disposed on the lower rectangular perimeter 172 .
[0025] The raised platform 120 is disposed on the surface of the base platform. The raised platform 120 may be rectangular in shape with two corners cut out on the side toward the center of the base platform 110 ; the two cut outs allowing the middle saver sub guides 155 to attach to the surface of the base platform 110 . The saver sub interface 130 is disposed on the surface of the raised platform 120 and houses various components (not shown) for interfacing with the saver sub.
[0026] FIG. 2 shows a cross-sectional view of the saver sub interface 130 , which includes: a top plate 135 , side walls 136 a , and the multiple quick connect (MQC) mating components. The MQC components include: bushing guides 131 , a lockdown housing 134 , and two pass through holes 133 . The MQC allows production fluid to be communicated between the manifold and saver sub (to be described in more detail below). The lockdown housing 134 is typically located in the center of the top plate 135 , is cylindrical, and protrudes below the surface of the top plate 135 . The lockdown housing 134 attaches with a locking mechanism on the saver sub (to be discussed in more detail below). On either side of the lockdown housing 134 are two pass through holes 133 that accommodate couplings (not shown). On either side of the pass through holes 133 are two bushing guides 131 . The bushing guides 131 are secured to the saver sub interface 130 by lock nuts 132 , and receive guide pins located on the saver sub (to be discussed in more detail below).
[0027] FIGS. 3 and 4 show protection plates 200 and 201 . The protection plates 200 , 201 , mount side by side on the sloped top structure 170 of the receiving structure 100 . Each protection plate has a locking mechanism 220 that mates with the sloped top structure 170 of receiving structure 100 . In addition, protection plate 200 also has saver sub guides 210 , similar to the corner saver sub guides 150 located on the receiving structure 100 .
[0028] As shown in FIGS. 5 and 6 , saver sub 300 includes a base structure 310 , a top plate 320 , a plurality of posts 340 , a three port bottle 370 , pipe work 380 , and retrievable skid guides 350 . The base structure 310 includes a top surface 310 a , a plurality of side surfaces 310 , and additional couplings and guidance pins to be described in more detail below. The top surface 310 a includes notches cut out of two corners, creating indented sides 310 b , 341 . A hole 375 is cut out of the top surface 310 a to allow the three port bottle 370 to sit approximately half above and half below the top surface 310 a.
[0029] FIG. 7 shows an underside view of the lower surface 311 c . The lockdown boss 334 is disposed on the underside of lower surface 311 c and connects to the lockdown housing 134 on the receiving structure 100 as shown in FIG. 2 . Couplings 333 are spaced from the lockdown boss 334 . The couplings 333 interface with the pass through holes 133 on the receiving structure 100 , as shown in FIG. 2 , and are positioned accordingly. The receiving structure guide pins 331 are disposed on the underside of the lower surface 311 c and aid in the proper alignment of the saver sub 300 with the receiving structure 100 during installation. The receiving structure guide pins 331 fit inside the bushing guides 131 shown in FIG. 2 .
[0030] FIG. 5 shows a plurality of posts 340 and 341 extending between the base structure 310 to the top plate 320 . As shown in FIG. 8 , the top plate 320 includes a lockdown bucket 330 , a lift mandrel 365 , retrievable skid guides 350 , and the mating MQC components: two retrievable skid guide pins 360 , lockdown boss 361 , one half inch coupling 362 , and two one inch couplings 363 .
[0031] The lockdown bucket 330 , shown in FIG. 5 , serves as the connection point for the ROV to lock the saver sub 300 onto to receiving structure 100 in a method as is known to those skilled in the art. The lockdown bucket 330 includes a releasable connection moveable between a locked and unlocked position and operable by the ROV. The lift mandrel 365 is disposed on the top plate 320 and protrudes above the top plate 320 . The lift mandrel 365 includes alternating cylindrical and conical sections, and is engageable by a lifting adapter (not shown) as is known by those skilled in the art. The lower portion of the two retrievable skid plate guides 350 are disposed on the top plate 320 and extend from the surface of the top plate 320 at the two posts 341 . The upper portion of the retrievable skid guides 350 is angled to aid the ROV operator to guide the retrievable skid 400 into the receiving structure 100 next to the saver sub 300 .
[0032] Two couplings 363 are located along top plate 320 . The couplings 363 interface with the retrievable skid MQC components (to be described below). The lockdown boss 361 is disposed in the smaller rectangular portion of the top plate 320 . The lockdown boss 361 mates with the lockdown boss of the retrievable skid (to be discussed below). The one half inch coupling 362 is disposed on the top plate 320 a distance away from the lockdown boss 361 . The coupling 362 also interfaces with the retrievable skid MQC components. The retrievable skid guide pins 360 are disposed away from coupling 362 and engage the bushing guides located on the retrievable skid (to be discussed in greater detail below).
[0033] FIG. 5 shows pipe work 380 disposed between the top plate 320 and the base structure 310 , which moves fluid between the manifold (not shown) and the retrievable skid 400 . The pipe work 380 connects various components; for example, pipe work 380 connects coupling 333 to the three port bottle 370 as well as the three port bottle 370 to the couplings 363 .
[0034] FIG. 11 shows the retrievable skid 400 with buoyancy shells 404 a and 404 b . The buoyancy shells 404 a , 404 b are attached to the chassis plate 403 (shown in FIG. 9 ) and, thus, form part of the structural frame of the retrievable skid 400 . The buoyancy shells 404 a , 404 b also serve to reduce the in-water weight of the retrievable skid 400 . However, it should be appreciated by one of skill in the art that the buoyancy shells 404 a , 404 b are not necessary for the retrievable skid 400 .
[0035] FIG. 9 shows the retrievable skid 400 without the buoyancy shells. The retrievable skid 401 includes a truss 402 , lockdown bucket 430 , hotstab 470 , pump 440 , sample chambers 420 (four are shown), and MQC components: bushing guides 460 , couplings 462 and 463 , and skid lockdown boss 461 . The truss 402 includes a chassis plate 403 with a plurality of cut outs to accommodate the mounting of various retrievable skid components, including the buoyancy shells 404 a , 404 b shown in FIG. 11 . The chassis plate 403 provides the structural support for the retrievable skid 400 and any impact loads received by a retrievable skid component is transferred to the chassis plate 403 . A plurality of additional posts also form the truss 402 .
[0036] The lockdown bucket 430 is disposed on the chassis plate 403 such that the aperture of the lockdown bucket 430 is disposed on the top surface of the truss 402 . The lockdown bucket 430 , shown in FIG. 11 , serves as the connection point for the ROV to lock the retrievable skid 300 onto to the saver sub 300 in a method as is known to those skilled in the art. The lockdown bucket 430 includes a releasable connection moveable between a locked and unlocked position and operable by the ROV.
[0037] The aperture of the electro-hydraulic hotstab receptacle 470 (referred to as “hotstab” hereinafter) is similarly disposed on the top surface of the truss 402 . The hotstab 470 mates with a hotstab counterpart on the ROV as known to those skilled in the art. The hotstab 470 is used for hydraulic power of the pump 440 and for power and communication for other components, supplied by the ROV (not shown). A flexible hose 475 connects the hotstab the hotstab pod 477 . The hotstab pod 477 is connected through the electrical harness 480 and the connector 490 to the sensor which is mounted to the chassis plate 403 .
[0038] The pump 440 , preferably a positive displacement pump, is preferably disposed in approximately the chassis plate 403 and connects to the hotstab 470 , the three port bottle 370 of the saver sub 300 , and the sample chambers 420 . The pump 440 is powered by the hotstab 470 and receives hydraulic power from an ROV (not shown). The pump 440 draws production fluid samples through the three port bottle 370 , fills the sample chambers 420 , and flushes the system. In a preferred embodiment, the pump 440 has three pumping modes: single phase, multiphase, and flushing.
[0039] The sample chambers 420 can be, for example, cylindrical, grouped in a 2×2 matrix formation, and disposed radially on the bottom surface of the chassis plate 403 , such that the sample chambers 420 surround the pump 440 . Although four sample chambers 420 are shown, any number of sample chambers may be used and positioned in any appropriate configuration. The preferred embodiment of a sample chamber 420 has three separate compartments—one for the fluid sample, one for MEG/water/glycol, and one for nitrogen. Filling the sample chamber 420 with fluid is facilitated by drawing water/glycol from the middle compartment, thus, drawing in the fluid sample. Once the sample chamber 420 is returned to the surface, 10% of the fluid sample is purged. Then the valve that communicates between the water and nitrogen compartments is opened, which allows a gas cap to be introduced to the sample.
[0040] The MQC components are shown in FIG. 10 . The bushing guides 460 and the two one inch couplings 463 are disposed on the chassis plate 403 . All the couplings 462 , 463 extend above and below the surface of the chassis plate 403 . The skid lockdown boss 461 also extends above and below the surface of the chassis plate 403 . The MQC components on the retrievable skid 400 interface with the upper MQC components of the saver sub 300 in like manner as the lower saver sub MQC components interface with the MQC components of the receiving structure 100 .
[0041] FIGS. 12 , 13 , and 15 show an embodiment for a sampling assembly for sampling production fluids from an oil or gas well. The well includes a structure, such as a manifold, an Xmas tree, or a length of pipe (not shown, generally referred to as “manifold”) and a sampling assembly that includes a receiving structure 100 , a saver sub 300 , a retrievable skid 400 , and protection plates 200 , 201 . The receiving structure 100 is secured to the manifold, from which production fluid samples will be taken. The receiving structure 100 is connected to the production flow in a manner known to those skilled in the art. The receiving structure 100 is considered non-releasably connected to the manifold, preferably welded into place. The connection is designed as a long term, permanent type connection rather than a quick connect/disconnect configuration. Via an ROV, as known to those skilled in the art, the saver sub 300 is guided by and installed on the raised platform 120 of the receiving structure 100 . The retrievable skid 400 is installed after the saver sub 300 and is transported and installed via ROV on the receiving structure 100 adjacent to the raised platform 120 . In a preferred embodiment, when the saver sub 300 and the retrievable skid 400 are installed in the receiving structure 100 , the receiving structure 100 transfers the load from the saver sub 300 and retrievable skid 400 to the manifold.
[0042] FIG. 13 depicts the components of the pump driven sampling assembly prior to integration. The saver sub 300 attaches to the receiving structure 100 at the saver sub interface 130 disposed on the raised platform 120 . Next, the retrievable skid 400 is placed, by ROV, in the receiving structure 100 ; the retrievable skid 400 partially overlaps and interfaces with the saver sub 300 .
[0043] The saver sub 300 accesses the production flow via its MQC connection with the receiving structure 100 . The retrievable skid 400 is then connectable to the saver sub 300 with the MQC “quick” connect/disconnect connection. Thus, the receiving structure 100 allows samples to be taken throughout the lifecycle of the manifold and the saver sub 300 reduces the number of makes and breaks on the couplings between the manifold and the receiving structure 100 —instead, the interface between the retrievable skid 400 and the saver sub 300 , and also possibly the interface between the saver sub 300 and the receiving structure 100 , is cycled with every sample taken. This saves the wear and tear on the manifold itself and allows for servicing the receiving structure 100 by replacing the saver sub 300 when needed as opposed to replacing parts on the manifold itself.
[0044] FIG. 15 shows the receiving structure 100 with protection plate 200 installed. Prior to the saver sub 300 installation, protection plate 200 is disposed on the receiving structure in the diametrically opposite side from the raised platform 120 . Saver sub guides 210 located on protection plate 200 serve to guide the saver sub 300 , as shown in FIG. 10 , into the proper location over the raised platform 120 and the saver sub interface 130 . Both protection plates 200 , 201 may be installed when the receiving structure 100 has no components installed or when only the saver sub 300 is installed. Both protection plates 200 , 201 are removed to allow for installation of the retrievable skid 400 .
[0045] The retrievable skid 400 shown in FIG. 12 extends above the top of the receiving structure 100 . In a preferred embodiment, the retrievable skid 400 can support its own weight and can withstand impacts from the ROV. FIG. 14 shows an alternative embodiment that includes an alternative receiving structure 102 , an alternative saver sub 302 , and an alternative retrievable skid 402 . In this embodiment, the alternative saver sub 302 and alternative retrievable skid 402 , when integrated in the alternative receiving structure 102 , are fully recessed below the level of the protection plates, 200 , 201 as shown in FIG. 14 , which reduces potential ROV impacts.
[0046] Although the present invention has been described with respect to specific details, it is not intended that such details should be regarded as limitations on the scope of the invention, except to the extent that they are included in the accompanying claims. | A sampling assembly for taking single or multiphase production fluid samples from a subsea well. The sampling assembly includes a receiving structure that houses a saver sub and a retrievable skid. The sampling assembly allows for repeated retrieval of collected samples and replenishment of empty sample chambers using the retrievable skid. A releasable connection interface between the retrievable skid and the saver sub allows an ROV to connect the retrievable skid to the saver sub and provide electrical and hydraulic power to the sampling assembly for taking samples. | 4 |
REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of co-pending U.S. patent application Ser. No. 10/872,241 filed Jun. 18, 2004, and incorporated by reference herein.
FIELD OF INVENTION
[0002] The present invention relates to a micromirror device with discrete multi-level positions.
BACKGROUND OF THE INVENTION
[0003] Micromirror devices have been developed because it can substitute for conventional optoelectronic devices. A phase-only piston-style micromirror was used for phase adaptive optics applications and a rotational micromirror was used to deflect a light. Most of these micromirrors have been controlled to have continuous displacements, which are determined at the equilibrium between electrostatic force and elastic force. The analog control is more complex than the digital or discrete control, and is not compatible with known semiconductor electronics technologies such as MOS, CMOS, etc. In addition, the micromirrors with continuous displacement actuated by electrostatic force undergo the classical snap-down phenomenon when the electric force exceeds the elastic force of mechanical structure. The snap-down phenomenon limits the translational and rotational ranges of a micromirror.
[0004] The high driving voltage is also another acute disadvantage in practical use of the micromirrors with continuous displacement actuated by electrostatic force. To be compatible with IC components, it is desired that micromirrors are operated at low voltage which is compatible with the circuit operation or control voltage.
[0005] In the prior art of micromirror array like Digital Micromirror Device in U.S. Pat. Nos. 4,566,939, 5,083,857, and 6,232,936, each micromirror is actuated by digital control of a voltage. It has large rotation, has a low driving voltage, and is compatible with known semiconductor electronics technologies. But, it has only single degree of freedom; rotation about an axis and two level positions. So, the micromirror array is merely the array of optical switches.
[0006] To be applied more widely, a micromirror is needed to have multi-level position control and large displacements, multi degrees of freedom motions, low driving voltage, and compatibility with known semiconductor electronics technologies.
SUMMARY OF THE INVENTION
[0007] The present invention contrives to solve the disadvantages of conventional micromirror devices with continuous displacement actuated by electrostatic force and limitations of Digital Micromirror Device (DMD).
[0008] An objective of the invention is to provide a micromirror with accurate and fast multi-level position control.
[0009] Another objective of the invention is to provide a micromirror with multi-degree-of-freedom motions.
[0010] Still another objective of the invention is to provide a micromirror with large displacements.
[0011] Still another objective of the invention is to provide a micromirror with very short settling time.
[0012] Still another objective of the invention is to provide a micromirror with low driving voltage compatible with known IC circuits operation or control voltage of IC circuits.
[0013] The conventional electrostatic micromirrors undergo the classical snap-down phenomenon when the electric force exceeds the elastic force due to mechanical structure. The snap-down phenomenon limits the translational and rotational ranges of a micromirror. The slow settling time of the conventional electrostatic micromirror reduces the operating speed of the micromirror. And, the high driving voltage of the conventional electrostatic micromirror gives difficulties in practical use. To be compatible with IC components which are normally operated at 5V or less than 5V and to prevent the electrical breakdown due to high electric field, the maximum value of the driving voltage should generally be as low as possible. Low displacement accuracy is also acute disadvantage of the conventional electrostatic micromirrors. The displacement accuracy goes bad by n times as spring thickness variation increases n times. To solve those disadvantages of the conventional electrostatic micromirrors, the Discretely Controlled Micromirror (DCM) is invented.
[0014] The first type of the DCM is the Variable Support Discretely Controlled Micromirror (VSCDM), which uses supports controlling gaps between the micromirror and substrate. The supports are located under the micromirror. Displacements of the DCM are determined by combinations of gaps, which are determined by the supports where the micromirror rests. The gaps determined by supports are controlled by electrostatic force and the micromirror rests on the controlled supports by an attractive electrostatic force. Digital voltage or discrete voltage operation is preferable method to control the electrostatic force. Therefore, combinations of gaps determine translation and rotation of the micromirror.
[0015] Three preferred VSDCM embodiments are explained. The first preferred embodiment is a micromirror comprising one or more digital supports. A gap that each support provides has two values because the gap is determined by bistable motion of the support. The motion is controlled by electrostatic force. Digital voltage or discrete voltage operation is preferable method to control the electrostatic force. The VSDCM uses bistable displacements of the supports for the displacement control of the micromirror.
[0016] The second preferred embodiment is a micromirror comprising one or more multi-level supports. A gap that each support provides has discrete multi-step because the gap is determined by discrete height change of the support. The height change is controlled by electrostatic force. Digital voltage or discrete voltage operation is preferable method to control the electrostatic force. The VSDCM uses the discrete height change of the supports for the displacement control of the micromirror.
[0017] The third preferred embodiment is a micromirror comprising one or more multi-position supports. In-plane position supporting the micromirror is controlled to be changed by the multi-position supports. Because the displacements of the micromirror are determined by not only heights of the supports but also the supporting positions, multi-position supports can control the displacements of the micromirror.
[0018] For the conventional electrostatic micromirror, the spring thickness accuracy of the micromirror determines displacement accuracy. The spring stiffness error of thin spring is higher than the spring stiffness error of thick spring if they have the same thickness error. Therefore, it is difficult to use low driving voltage because thin spring is undesirable. Because the VSDCM uses bistable or discrete displacement, spring thickness accuracy is not critical. Therefore, the spring of the micromirror with very low stiffness can be used. The VSDCM with the spring of low stiffness can be operated by low voltage. Independently controlled variable supports require individually addressable electronics. To achieve this, the micromirror combined with on-chip electronics is used. In order to do this, wafer-level integration of the micromirror with known semiconductor microelectronics is used.
[0019] Because the micromirror rests on the variable supports of the VSDCM, thickness accuracy of the variable supports is the displacement accuracy of micromirror. The VSDCM has much better accuracy for large displacement because the accuracy is not dependent on the range of displacement.
[0020] The second type of DCM is the Segmented Electrode Discretely Controlled Micromirror (SEDCM), which uses the segmented electrode pads. The SEDCM has the same disadvantages like small displacement range and poor accuracy for large displacement as the conventional electrostatic micromirrors do. But, The SEDCM is compatible with known semiconductor microelectronics technologies because the SEDCM can be controlled by discrete voltage. Displacements of the micromirror can be controlled by appropriate combinations of area size, position, and voltage of each electrode pad.
[0021] The VSDCM and the SEDCM can be fabricated with two different methods. The first method uses metals; aluminum, nickel, gold, and copper for structural layer, and photoresist or SiO 2 for the sacrificial layers that forms the air gaps. The fabrication of the DCM begins with a wafer on which a completed semiconductor microelectronics circuit is fabricated. A thick oxide is deposited over metal of the semiconductor microelectronics and then planarized using known polishing methods such as chemical mechanical polishing (CMP) techniques and so on. The polishing step provides a completely flat surface for the digital structure. The CMP ensures that thickness variation, flatness and reflectivity of micromirrors are not degraded. Through the use of several photomask layers, the structure of micromirrors is formed with metal layers for the spring, posts, and micromirror layer. And the air gap of DCM is formed by known sacrificial materials such as photoresist or SiO 2 . A metal is sputter-deposited or evaporated and plasma-etched by using plasma-deposited SiO 2 as the etch mask. Later in the packaging flow, the sacrificial layers are plasma-ashed to form the air gaps.
[0022] The second method uses known electroplating techniques. This method utilizes a sacrificial metallic mold, which plays multiple roles of an electroplating mold for posts and seed layers for next-level electroplating at the same time. Therefore, this method can simplify the fabrication process and demonstrate real 3-D metallic microstructures without limitation on the number of levels. This method only uses conventional lithography and electroplating, and known polishing such as CMP. As an example, electroplated nickel is used for structural layers and electroplated copper is used for sacrificial layers, respectively.
[0023] The reflective surface of the micromirror is made of metal, metal compound, multi-layered dielectric material, or other materials with high reflectivity. Many known microfabrication processes can make the surface of the micromirror to have high reflectivity. The micromirrors are electrostatically controlled to have desired positions with actuating components. According to applications, a translation, a rotation, a translation and a rotation, or a translation and two rotations can be controlled.
[0024] As described in the applicant's U.S. patent application for “Variable Focal Length Lens Comprising Micromirrors with Two Degrees of Freedom Rotation”, which was filed on May 27, 2004, applicant's another U.S. patent application for “Variable Focal Length Lens Comprising Micromirrors with Two Degrees of Freedom Rotation and One Degree of Freedom Translation” which was filed on May 27, 2004, and the applicant's still another U.S. patent application for “Array of Micromirror Array Lenses”, which was filed on May 28, 2004, the disclosures of which are incorporated by reference as if fully set forth herein, the micromirror array comprising the micromirrors with two degrees of freedom rotation or two degrees of freedom rotation and one degree of freedom translation which are controlled independently can modulate incident lights arbitrarily. In order to do this, it is required that incident lights are deflected to a desired arbitrary direction by controls of two degrees of freedom rotation or controls of two degrees of freedom rotation and one degree of freedom translation. Independent translation of each micromirror is also required to satisfy the phase condition. Because the DCM have many advantages and can have two degrees of freedom rotation and/or one degree of freedom translation, the micromirror array comprising the DCM has better performance than the conventional micromirror array.
[0025] Electric circuits to operate the micromirror array can be replaced with known MOS or CMOS technologies, which are widely used in microelectronics. By applying the microelectronics circuits under the micromirror array, the effective reflective area can be increased by removing necessary area for electrode pads and wires. Each micromirror can tilt along two axes as well as retract. As a result the micromirror can scan a field of view along both vertical and horizontal axes and simultaneously retract or elevate to remove phase aberrations of an incident optical beam. The micromirror array can correct aberration, e.g. optical effects due to the medium between the object and its image or defects of a lens system that cause its image to deviate from the rules of paraxial imagery, by controlling each micromirror independently. To compensate for aberration with arbitrary phase error, each micromirror of micromirror array should be controlled independently. Independent control of each micromirror is possible by replacing electric circuits required for control with known CMOS technologies and fabricating the CMOS underneath the micromirrors using known microfabrication methods.
[0026] The micromirrors of the invention are desirably shaped to permit a closely packed array and can be rounded in shape but desirably are angular, e.g. triangular, rectangular or have five or more sides, including hexagonal, octagonal and the like.
[0027] In order to achieve the above objectives, the first type of the present invention provides a discretely controlled micromirror (DCM) that includes a micromirror and a plurality of variable supports on which the micromirror rests. The variable supports determine the position of the micromirror, and the variable supports are controlled by electrostatic force. Digital voltage or discrete voltage operation is preferable method to control the electrostatic force. The variable supports are located under the micromirror. In-plane position of the variable supports is variable to get arbitrary displacements of the micromirror from digital or discrete variable supports.
[0028] The variable supports are placed between the micromirror and a substrate. Each of the variable supports is controlled to change its height so that the position of the micromirror is controlled.
[0029] The variable supports determine the gap between the micromirror and the substrate.
[0030] Each of the digital supports comprises a top post, a bottom post, and/or one or more inserter that is inserted between the top post and the bottom post in its on position and taken out from the gap between the top post and the bottom post in its off position.
[0031] The gap is determined by whether the inserter is placed between a top post and a bottom post.
[0032] Each of the discrete supports comprises a top post, a bottom post, and/or one or more multi-step inserter that is inserted between the top post and the bottom post. The inserter with multi-step thickness determines displacements of the micromirror according to the inserted amount.
[0033] The gap is determined by the inserted amount of the multi-step inserter.
[0034] The inserter is controlled by electrostatic force.
[0035] The inserter is controlled by digital voltage or discrete voltage operation.
[0036] The inserter has in-plane translation. The in-plane translation is actuated by a comb-drive.
[0037] The inserter has multi-step thickness.
[0038] The in-plane positions of the variable supports are changed.
[0039] In the operation of DCM, the rotation and/or translation of the micromirror is controlled. Both rotation and translation of the micromirror are controlled by three or more than three variable supports. The variable support has bistable motion. The variable support has discrete motion. The micromirror rests on the controlled variable support by attractive force.
[0040] The surface material of the micromirror is the one with high reflectivity. The surface material of the micromirror may be metal or metal compound. Also the surface of the micromirror is made with multi-layered dielectric coating.
[0041] The DCM is made by a method in which the material of a structural layer is metal. An aluminum layer is sputter-deposited and plasma-etched using plasma-deposited SiO 2 as an etch mask. The sacrificial layers are plasma-ashed to form the air gaps.
[0042] The DCM is made by a method in which layers deposited by microfabrication process are planarized using a chemical mechanical polishing (CMP) technique.
[0043] In the DCM, the micromirror is fabricated using electroplating techniques. The electroplating technique uses the unique sacrificial metallic mold that plays multiple roles of an electroplating mold for posts and seed layers. Electroplated nickel is used for structural layers. Electroplated copper is used for sacrificial layers.
[0044] The invention also provides a DCM array comprising a plurality of the above-described DCM. In the DCM array, the micromirrors are controlled independently. The micromirror array is a Spatial Light Modulator (SLM).
[0045] A control circuitry is constructed under the micromirror using microelectronics technologies. A thick oxide is deposited over metal of the microelectronics circuits.
[0046] The second type of the invention provides a DCM that includes a micromirror and a plurality of segmented electrodes. The segmented electrodes determine the displacements of the SEDCM. The applied voltage to segmented electrodes is discrete. The SEDCM is controlled by electrostatic force. The SEDCM is controlled by digital voltage or discrete voltage operation. The segmented electrodes are located under the micromirror. In-plane positions of the segmented electrodes are changed.
[0047] In the operation of the SEDCM, rotation and/or translation of the micromirror is controlled. The areas of the segmented electrodes are changed. The surface material of the SEDCM has high reflectivity. The surface material of the SEDCM may be metal or metal compound. Also, the surface of the SEDCM is made with multi-layered dielectric coating.
[0048] The SEDCM is made by a method in which the material of structural layer is metal. An aluminum layer is sputter-deposited and plasma-etched using plasma-deposited SiO 2 as an etch mask. The sacrificial layers are plasma-ashed to form the air gaps.
[0049] The SEDCM may be made by a method in which layers deposited by microfabrication process are planarized using a chemical mechanical polishing (CMP) technique.
[0050] The micromirror is fabricated using electroplating techniques. The electroplating technique uses the unique sacrificial metallic mold, which plays multiple roles of an electroplating mold for posts and seed layers. Electroplated nickel is used for structural layers. Electroplated copper is used for sacrificial layers.
[0051] The invention also provides a DCM array comprising the previously described DCM. In the array, the micromirrors are controlled independently. The micromirror array is a Spatial Light Modulator (SLM). A control circuitry is constructed under the SEDCM using microelectronics technologies. A thick oxide is deposited over metal of the microelectronics circuits.
[0052] Although the present invention is briefly summarized, the full understanding of the invention can be obtained by the following drawings, detailed description, and appended claims.
BRIEF DESCRIPTION OF THE FIGURES
[0053] These and other features, aspects and advantages of the present invention will become better understood with reference to the accompanying drawings, wherein
[0054] FIG. 1 is a schematic diagram showing the DCM with variable supports;
[0055] FIG. 2 is a schematic diagram showing how the VSDCM has three degrees of freedom motions; one translation motion along the normal axis to the plane of the micromirror and two rotational motions about the axes in the plane;
[0056] FIGS. 3 a - 3 d are schematic diagrams showing digital variable supports and four different displacements of the DCM comprising the digital variable support;
[0057] FIG. 4 is a schematic diagram showing an inserter actuating system including inserter;
[0058] FIG. 5 is a schematic diagram showing an inserter actuating system using a comb-drive;
[0059] FIG. 6 is a schematic diagram showing a discrete variable support with the multi-step inserter;
[0060] FIGS. 7 a and 7 b are schematic diagrams showing a multi-position support; and
[0061] FIG. 8 is a schematic diagram showing the DCM comprising segmented electrodes.
DETAILED DESCRIPTION OF THE INVENTION
[0062] FIG. 1 shows the concept of DCM with the variable supports 1 . The variable support discretely controlled micromirror (VSDCM) use supports 1 providing various gaps between the micromirror 2 and substrate 8 . The supports 1 are located under the micromirror 2 . Translation and rotation of the VSDCM are determined by combination of the gaps, which are determined by variable supports 3 , 4 that the micromirror 5 rests. The gaps determined by the variable supports are controlled digitally or discretely and the micromirror rests on the controlled supports 3 , 4 by attractive force 6 . Therefore, the gaps provided by the supports determine translation and/or rotation of the micromirror. Gap variation by the supports is determined by digital or discrete motion of the supports and the motions are controlled by electrostatic force. Digital voltage or discrete voltage operation is preferable method to control the electrostatic force. The position of micromirror 5 is restored into initial position by force of flexible spring 7 when the attraction force is off.
[0063] FIG. 2 shows how the VSDCM can have motions of three degrees of freedom; one translational motion along the normal axis to the plane of the micromirror and two rotational motions about the axes in the plane. When three variable supports 11 , 12 , 13 or more than three variable supports among many variable supports 14 are used to support the micromirror 15 , the VSDCM has three degree of freedom. Three variable supports are enough to make three degree of freedom of micromirror, but more than three variable supports can be used so that the micromirror which rests on supports stays stably.
[0064] Height accuracy of the variable supports gives the displacement accuracy of the VSDCM because the micromirror 15 rests on the variable supports 11 , 12 , 13 . The thickness control accuracy of microfabrication to make the variable support is less than several nanometers. The displacement accuracy of conventional electrostatic micromirror goes bad by n 3 times as spring thickness variation of the micromirror increases n times. Therefore, the VSDCM has much better accuracy in control of displacement than the conventional electrostatic micromirror.
[0065] FIGS. 3 a - 3 d show an exemplary digital variable support and four possible displacements of the VSDCM supported by the two variable supports 23 , 24 .
[0066] The variable supports 23 , 24 are placed between the micromirror 25 and a substrate 27 . Each of the variable supports 23 , 24 is controlled to change its height so that the position of the micromirror 25 is controlled.
[0067] Even though FIGS. 3 a - 3 d show the digital VSDCM, supported by two variable supports, with two degrees of freedom (one translational motion and one rotational motion), many variable supports can be made under the micromirror and the micromirror, supported by three or more variable supports, with three degrees of freedom (one translational motion and two degrees of rotational motion) is also possible. The variable supports 23 , 24 comprise an inserter 20 , a top post 21 and/or a bottom post 22 . The inserter 20 with bistable motion is controlled by electrostatic force. Digital voltage or discrete voltage operation is preferable method to control the electrostatic force. Each variable support 23 , 24 controlled by the electrostatic force can provide controllable two different gaps G 1 , G 2 depending on whether the inserters 20 are inserted or not. The inserter 20 , the top post 21 and the bottom post 22 can have different heights because combination of their heights can make various gaps. Each support provides two positions, on-off positions, to a micromirror 25 at the position where the support is located. Since a translation and a rotation of the VSDCM are determined by combinations of the gaps provided by the supports 23 , 24 actuation, the number of feasible displacements is 2 n , where n is the number of supports. At the discrete gaps given by the supports, the micromirror 25 can have desired translation and rotation by adjusting the in-plane position of each support.
[0068] FIG. 4 shows an example of an inserter actuating system including an inserter 30 . The inserter actuating system comprises two bottom electrodes 31 a , 31 b , a top electrode 32 , one or more springs 33 , one or more posts 34 , and an inserter 30 . The top electrode 32 held by the springs 33 is actuated by electrostatic force between the top electrode 32 and one of the bottom electrodes 31 a , 31 b . In this way, the inserter 30 on the top electrode 32 can be moved.
[0069] FIG. 5 shows another example of an inserter actuating system. An inserter 41 should have in-plane translation. A very well-known comb-drive 40 may give in-plane translation to the inserter 41 .
[0070] FIG. 6 shows a multi-step inserter 42 to make multi-step gaps. In contrast with the inserter 30 with one thickness, the multi-step inserter 42 has several step thicknesses. According to in-plane position of the inserter 42 , the thickness of the multi-step inserter located between a top post 43 and a bottom post 44 is changed. Therefore, displacement of a micromirror 45 can be changed. Very well-known comb-drives may give in-plane translation 46 to the multi-step inserter 42 .
[0071] FIG. 7 a shows a top view of multi-position support comprising the inserter 47 , 48 and several posts 49 with different in-plane positions. FIG. 7 b shows a three-dimensional drawing of the multi-position support to show the structure clearly. The supported position is changed by in-plane translation of the inserter 47 , 48 . For an example, the supporting position 49 A of the micromirror 52 is changed to position 49 B by in-plane translation 50 of the inserter 47 . The supporting position 49 C of the micromirror 52 is changed to position 49 D by in-plane translation 51 of the inserter 48 . Very well-known comb-drives may give the in-plane translation 50 , 51 to the inserter 47 , 48 .
[0072] The supporting system combining the multi-position and the multi-step also can be used.
[0073] FIG. 8 shows the second type of the DCM using segmented electrodes 60 . In contrast with conventional electrostatic micromirrors, this embodiment comprises segmented electrodes 60 with different areas, positions, and discrete voltages. This embodiment has the same disadvantages as the conventional electrostatic micromirror except for compatibility with known microelectronics technologies for the control circuit. The micromirror 61 can have the desired three degrees of freedom by the appropriate combinations of segmented electrodes 60 with different areas, positions, and discrete voltages.
[0074] The VSDCM and the SEDCM can be fabricated by two different methods. The first method uses metals such as aluminum, nickel, gold, and copper for structural layer, and photoresist or SiO 2 for the sacrificial layers that form the air gaps. The fabrication of the DCM begins with a wafer on which a completed microelectronics addressable circuits are fabricated. A thick oxide is deposited over metal of the circuits and then planarized using known polishing methods such as chemical mechanical polishing (CMP) techniques and so on. The polishing step provides a completely flat surface for the digital structure. The CMP ensures that thickness variation, flatness, and reflectivity of micromirrors are not degraded. Through the use of several photomask layers, the structure of micromirrors is formed with metal layers for the spring, posts and, micromirror layer. And, the air gap of DCMs is formed with photoresist or SiO 2 . A metal is sputter-deposited and plasma-etched by using plasma-deposited SiO 2 as the etch mask. Later in the packaging flow, the sacrificial layers are plasma-ashed to form the air gaps.
[0075] The second method uses known electroplating techniques. This method utilizes the unique sacrificial metallic mold that plays multiple roles of an electroplating mold for posts and seed layers for next-level electroplating at the same time. Therefore, this method can simplify the fabrication process and demonstrate real 3-D metallic microstructures without limitation on the number of levels. This method only uses conventional photolithography and electroplating, and known polishing such as CMP. As an example, electroplated nickel is used for structural layers and electroplated copper is used for sacrificial layers respectively.
[0076] The reflective surface of the micromirror is made of metal, metal compound, multi-layered dielectric material or other materials that have high reflectivity. Many known microfabrication processes can make the surface of the micromirror to have high reflectivity. The micromirrors are electrostatically controlled to have desired positions by actuating components. Depending on applications, a translation, a rotation, a translation and a rotation, or a translation and two rotations can be controlled.
[0077] The array comprising the DCM with two degrees of freedom rotations or two degrees of freedom rotations and one degree of freedom translation, which are controlled independently, can modulate incident lights arbitrarily. To do this, it is required that incident lights are deflected to the desired arbitrary directions by controls of two degree of freedom rotations or controls of two degree of freedom rotations and one degree of freedom translation. Independent translation of each micromirror is also required to adjust the phase of light.
[0078] The micromirror array can correct aberration, which is caused by optical effects due to the medium between the object and its image or is caused by defects of a lens system that cause its image to deviate from the rules of paraxial imagery, by controlling each micromirror independently.
[0079] Electric circuits to operate the micromirrors can be made with known the microelectronics circuits technologies where are used in microelectronics. Applying the microelectronics circuits under micromirror array, the effective reflective area can be increased by removing necessary area for electrode pads and wires. Independent control of each micromirror is also possible by making electric circuits required for control with known microelectronic circuit technologies. To increase optical efficiency, the microelectronics circuit is fabricated underneath the micromirrors by using known microfabrication methods.
[0080] The variable supports and the microelectronics circuits are positioned beneath the micromirror so that no reflective service area is lost to these features. This means that individual micromirror assemblies can be placed closer to each other in order to maximize the effective area.
[0081] While the invention has been shown and described with reference to different embodiments thereof, it will be appreciated by those skills in the art that variations in form, detail, compositions and operation may be made without departing from the spirit and scope of the invention as defined by the accompanying claims. | This invention provides the two types of Discretely Controlled Micromirror (DCM), which can overcome disadvantages of the conventional electrostatic micromirrors. The first type micromirror is a Variable Supporter Discretely Controlled Micromirror (VSDCM), which has a larger displacement range than the conventional electrostatic micromirror. The displacement accuracy of the VSDCM is better than that of the conventional electrostatic micromirror and the low driving voltage is compatible with IC components. The second type of DCM, the Segmented Electrode Discretely Controlled Micromirror (SEDCM) has same disadvantages with the conventional electrostatic micromirror. But the SEDCM is compatible with known microelectronics technologies. | 6 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is the U.S. national phase of International Application No. PCT/EP2004/011573 filed 14 Oct. 2004 which designated the U.S., the entire contents of which are hereby incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
FIELD
The technology herein relates to a locking arrangement for fixing two items of furniture to one another.
BACKGROUND AND SUMMARY
Unit-furniture systems in their wide-ranging forms are sufficiently well known. Box-shaped office furniture systems or shelving systems are also very popular. These can be assembled with a high degree of variability for example from individual container-shaped or generally box-shaped basic units, which are sometimes also referred to below as modules. The modules may be left open for example, but may also be provided at their front with a wide range of flaps. Drawer elements may also be incorporated, etc.
Such a shelving system which can be assembled using a modular method of construction is then faced for example with the problem of how to fix the individual modules as simply as possible yet effectively to one another so that a stable overall construction finally results.
An exemplary illustrative non-limiting implementation provides an improved locking system for items of furniture, in particular for box-shaped modular or basic units, in order to fasten or fix such individual parts to one another.
An exemplary illustrative non-limiting implementation provides a highly efficient connecting system with which the individual items of furniture to be connected can be provided at the factory. The basic principle is such that any desired items of furniture, for example box- or container-shaped basic or modular units, provided with corresponding connecting and locking devices can be placed one on top of the other so that it is then merely necessary for example, to actuate the locking or latching device provided on the modular unit placed on top, thereby fixedly connecting the two items of furniture to one another.
The structure is preferably such that not only similar or functionally identical but, in particular, identical locking base sections are provided on each item of furniture, these being positioned in such a way that, given a corresponding structure, the locking elements provided on the two items of furniture in each case come to lie congruently to one another. Where the structure is identical it is then possible, depending on which locking base section is more easily accessible, to use the latter in turn to carry out the locking with the respective other locking section. The locking is preferably performed simply by pressing in and twisting an actuating part.
A bayonet-type locking mechanism is preferably provided. For this purpose, defined projections or depressions are formed on the individual sections and elements which interact with one another in order to produce the desired bayonet-type closure mechanism. Preferably provided locking arms may consist of arms which project radially outwards from a central section of the rotatable locking element. In the case of the basic unit, two diagonally extending locking arms are preferably provided. However, in a preferred development, the locking element is provided with locking arms arranged in a cross shape. This offers the possibility, for example, that the containers to be built one on top of the other can also be mounted on one another in a position in which they have been rotated through 90°, which means that the opening side of a box-shaped container may for example be oriented not only to the front, but also to the left, to the right or to the rear as desired. This does not have a disadvantageous effect on the effectiveness of the locking device.
In a particularly preferred embodiment, the individual locking sections are designed in such a way that they correspond to the shape of a through opening in a cup-shaped bottom section of the respective locking element and, in a basic position, come to lie at the level of this through opening. The entire locking base section is thus incorporated securely against rotation in a furniture part. The furniture part equipped with such a locking element is therefore virtually closed in a continuous outer surface, since the locking arms of a locking element come to lie at the level of the through opening, this opening thereby being virtually covered.
In an exemplary illustrative non-limiting implementation, provision is also made for a spring device which applies force to the adjustable locking or rotating part in its unlocked basic or starting position. This ensures that the locking arms in their basic or starting position come to lie exactly in the plane of the through opening in the cup-shaped bottom of a locking base section. This also has the advantage that during an unlocking operation—when the locking arms are rotated into the release position, in which position they come to lie congruently to the through opening in the cup-shaped bottom section of a locking base—the corresponding locking element is then lifted into its unlocked position by the spring action. In this position, a further clamping mechanism which then retains the rotating part in this axial position is also provided.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features and advantages will be better and more completely understood by referring to the following detailed description of exemplary non-limiting illustrative implementations in conjunction with the drawings of which:
FIG. 1 shows a schematic perspective representation of a furniture system which is composed of a plurality of container elements;
FIG. 2 shows a schematic perspective representation of an exemplary illustrative non-limiting first locking element incorporated in a container bottom;
FIG. 3 shows a corresponding perspective representation of a second exemplary illustrative non-limiting identical locking device which is incorporated in a top wall of a container furniture item and interacts in the locked state with the first locking device depicted in FIG. 2 ;
FIG. 4 shows a schematic top view of an exemplary illustrative non-limiting locking device;
FIG. 5 shows a bottom view of an exemplary illustrative non-limiting locking device;
FIG. 6 shows a schematic cross-sectional representation through a locking device;
FIG. 7 shows a cross-sectional representation corresponding to FIG. 6 but in which the cross section runs diagonally through a cross-shaped locking element;
FIG. 8 shows a corresponding cross-sectional representation to FIG. 7 , but in the locking position, in which two locking devices situated in mirror-image form with respect to one another, and thus two bottoms of two items of furniture, are fixed to one another;
FIG. 9 shows a schematic perspective representation of an exemplary illustrative non-limiting rotating part having locking arms which are slightly roof-shaped in cross section;
FIG. 10 shows a schematic top view of an empty cup- or housing-shaped fixed part having locking depressions in the remaining locking projections so as to achieve a bayonet-type locking mechanism.
DETAILED DESCRIPTION
The schematic perspective representation in FIG. 1 shows three box- or container-shaped items of furniture 1 which are built one on top of the other and fixed to one another.
FIG. 1 shows two items of furniture 1 of relatively large dimensions built one on top of the other, the depth and height of which are dimensioned to be identical, so that the corresponding end face is formed square. The length is twice as long as the height or depth. A locking device 9 , which will be discussed in more detail below, is incorporated in the center of each of the vertical side walls 1 a . The same applies to the opposite vertical side wall 1 b . Locking devices 9 are likewise also incorporated in the lower bottom board 1 c and the upper top board 1 d , and, since the bottom board 1 c and the top board 1 d are twice as large as the end-forming side walls 1 a and 1 b , provision is made there in each case for two locking devices 9 which are arranged centrally in the transverse direction of the rectangular bottom and top board and thus have a longitudinal space corresponding to half the length of these board-shaped wall elements, the spacing from the center of one locking device 9 to the end of the rectangular bottom being a quarter of the overall length of the board.
For the purpose simply of illustrating various possible construction variants, FIG. 1 also shows a further container element 1 ′ which is built on and mounted at the top, this element having only half the length of the container elements 1 situated below and having only one centrally arranged locking device 9 in the bottom board 1 c and the top board 1 d respectively.
This very construction shows that in each case the locking device 9 incorporated in a bottom board 1 d comes to lie, when seen from the top, directly adjacent and congruent to a respective locking device 9 which is provided in an underlying top board 1 d of an immediately neighbouring box- or container-shaped item of furniture 1 .
According to the exemplary embodiment described, all of the stated locking devices 9 are functionally identical and at the same time preferably even identical in design, in which regard two respective locking devices 9 situated in mirror-image form with respect to one another interact and form an exemplary illustrative locking arrangement.
Reference will be made in the text below to FIGS. 2 and 3 , FIG. 2 being a schematic perspective representation showing a locking device 9 viewed more or less from the upper side and FIG. 3 showing a corresponding locking device 9 viewed more or less from the lower side, specifically illustrating how two locking devices 9 interact, for example at the point indicated by “A” in FIG. 1 , in order to fixedly connect an upper bottom board 1 c to an underlying top board 1 d of two furniture containers 1 . As will be further discussed below, when in use not only do the two boards 1 c and 1 d then lie against one another along a common add-on plane 11 , but also the two locking devices according to FIG. 3 and FIG. 4 touch one another with their bottom faces or are positioned with only a small spacing. In other words, the two locking devices 9 shown in FIGS. 3 and 4 are brought into contact or direct contact in the add-on direction indicated by the arrow 13 . The stated add-on plane 11 corresponds for example to a horizontal plane. FIGS. 2 and 3 thus already show that the respectively interacting locking devices 9 have a cup-shaped basic structure, that is to say comprise a cup-shaped fixed part, housing part or base part 15 which has a cup-shaped or cylindrical boundary wall 15 a and a bottom 15 b.
In the exemplary embodiment shown, each locking device 9 additionally comprises a peripheral edge or flange 15 c which, in the exemplary embodiment shown, comes to lie at the level of the upper cup opening 17 , i.e. opposite the lower bottom 15 b.
Each of the locking devices 9 has overall a configuration which deviates from a circular shape in order finally to be able to be incorporated securely against rotation in a shelf board or bottom board. In the exemplary embodiment shown, the cylindrical boundary wall 15 a of the cup-shaped locking device 9 is not secure against rotation per se. However, the upper flange-shaped edge 15 c is formed elliptically. An elliptical depression, corresponding to the material thickness of this edge, is made in the respective furniture board 1 c or 1 d in addition to a cylindrical bore 19 which passes right through the board, with the result that it is impossible to rotate the locking device 9 after it has been inserted. Otherwise, for example, one or two screws 21 passing through the flange-shaped edge 15 c could also be screwed into the respective board 1 c or 1 d to prevent rotation even with a circular edge or flange 15 c.
Moreover, it will also be possible for the cup-shaped design of the base part or fixed part 15 to have, for example at the outer periphery, a configuration which deviates from a cylindrical cross section so as to ensure a rotationally secure fit through a shelf board in a correspondingly fashioned bore 19 . However, this involves more effort.
FIG. 4 shows a schematic axial top view and FIG. 5 shows a schematic axial bottom view of the locking device 9 described. It can be seen from FIG. 5 that the disc-shaped bottom 15 b of the locking device 9 has a cross-shaped cutout 23 . In the exemplary embodiment shown, this cutout 23 is of symmetrical design starting from a central axis line 25 , which means that the arm-shaped opening regions 23 ′ emanating radially from the central axis 25 have the same radial length and the same width extending transversely to the radial direction.
An adjusting member 29 , which is also sometimes referred to below as a rotating part 29 , is arranged in the cup-shaped interior 27 of each locking device 9 , i.e. in the cup-shaped interior 27 of the base part or fixed part 15 of a respective locking device 9 . This rotating part 29 comprises a cover cap-shaped actuating part 29 a , a driver 29 b situated below the latter and axially adjoining the actuating part 29 a , and a locking element 29 c arranged on the underside of the driver 29 b . The aforementioned sections 29 a to 29 c of the incision member or rotating part 29 thus formed are fixed in terms of rotation relative to one another. In addition, the rotation part 29 thus formed may be formed in one piece. However, it is also possible for the driver 29 b to be able to be retracted and extended axially, i.e. telescopically, to a small extent; in other words, the axial length of the driver is adjustable.
In the exemplary embodiment shown, the locking element 29 c comprises four locking arms 31 emanating from the central axis 25 , these arms likewise again being cross-shaped in their configuration and their arrangement, i.e. corresponding in this respect to the cross-shaped cutout 23 . However, the width and length of these locking arms 31 are designed in such a way that their dimensions are correspondingly smaller, with the result that, even in the basic position according to FIG. 3 or 5 , these locking arms 31 are surrounded by a peripheral gap 33 even if they are arranged at the level of the bottom 15 b in the cutout 23 situated in the bottom. An overall clearance is thereby achieved, which will be further discussed below.
As can be seen from the cross-sectional representations according to FIG. 6 et seq., there is additionally provided in the interior 34 a spring device 35 which is supported on the one hand on the cup-shaped housing, i.e. on the bottom 15 b of the base part or fixed part 15 , and on the other hand on the underside of the cover cap-shaped actuating part 29 a . Since the rotating part 29 is held captively in the cup-shaped housing part (also sometimes referred to below as fixed part 5 ), the rotating part 29 cannot be pushed out or fall out of the cup-shaped receiving space 34 . For this purpose, at least two projections, preferably a plurality of projections, which are situated offset from one another in the circumferential direction, or a peripheral closed abutment edge 37 against which the cover cap-shaped actuating part 29 a would butt, are formed at the level of the flange-shaped edge 15 c . The axial longitudinal extent of the rotatable adjusting member or rotating part 29 is in this case such that, in the basic position according to FIG. 6 , the arm-shaped and radially projecting locking arms 31 come to lie exactly at the level of the cross-shaped cutout 23 in the bottom 15 b . The spring device 35 mentioned is in this case coordinated in such a way that the prestressing force of the spring exerts adjustment forces on the rotating part 29 in the direction of the upper flange-shaped edge 15 c , but only until the cover cap-shaped actuating part 29 reaches the basic position shown in FIG. 6 . In this basic position there still remains per se a further axial adjustment travel until the cover cap-shaped actuating part 29 a abuts against the upper edge 37 . However, in the position shown in FIG. 6 , the one or more projections 38 (indicated in FIG. 9 ) formed on the peripheral edge of the cover cap-shaped actuating part 29 a interacts with the depressions made at corresponding points in the inner wall of the cup-shaped central section of the fixed part 15 . This also results in a pre-adjustment and alignment of the cross-shaped locking arms 31 , since it is precisely in that position that the locking arms 31 can be brought into the same cross-shaped alignment as the cross-shaped cutout 23 . The projections 38 engaging in the depression 43 in the peripheral wall 15 a of the fixed part 15 in this case additionally produce a certain frictional locking. This also ensures that the spring force of the spring device 35 per se cannot cause the insert part or rotating part 29 to be further adjusted by the force of the spring alone, as is shown in FIG. 6 .
The above-described construction also results in the fact that when correspondingly shaped containers are supplied, the cover cap-shaped cover 29 is situated virtually with a small spacing below the level surface of the outer boundary plane 1 e of a corresponding wall of the box-shaped container, and also the opposite level surface 1 f is closed virtually over the whole surface by the bottom and the locking element 29 c seated in the cutout 23 in the bottom 15 b.
FIG. 7 corresponds substantially to the representation according to FIG. 6 , but with the difference that in FIG. 7 the rotating part or adjusting member 29 is pressed against the force of the spring energy store device 35 in the direction of the bottom 15 b , with the result that the locking element 29 c with the mutually opposite locking arms 31 is pressed downward beyond the surface of the bottom 15 b into that position in which the actual locking is then carried out. Since the sectional representation according to FIG. 6 and FIG. 7 is represented diagonally through the cross-shaped locking element 29 c , the overall length of the locking elements 31 can only be seen in FIG. 7 , not in FIG. 6 .
If two containers are placed one on top of the other in the correct position corresponding to FIG. 1 and are to be fixed to one another, two locking devices 9 described come to lie directly congruent to one another corresponding to the representation according to FIG. 8 . Here, the two locking devices 9 which come to lie adjacently are oriented in mirror-image form with respect to their central add-on plane 11 , i.e. with their two bottoms lying on one another. The side on which the bottoms come to lie in each case represents the respective outer side of a corresponding container, with the result that the cover cap-shaped actuating part 29 a is in each case freely accessible from the inner side of a container.
In order to carry out locking of two items of furniture, the freely accessible cover cap-shaped actuating part 29 in one of the two locking devices 9 , for example in the upper locking device 9 in FIG. 8 , is pressed in against the force of the spring energy store 35 . Since the two cross-shaped locking elements 29 c of the upper and lower locking devices 9 are situated one on top of the other, pressing in the upper rotating part 29 thus causes the lower locking element 29 c to be displaced axially downwards, or the locking elements 29 c belonging to the lower locking device 9 are adjusted by the telescopically retractable and extendable driver unit 29 a (if such a mechanism is provided) in such a way that the locking element 29 c connected fixedly in terms of rotation to the upper actuating part 29 a has its four radially projecting locking arms or fingers 31 situated in the interior 34 of the fixed part 15 situated in the other shelf board, i.e. in the lower shelf board, specifically directly adjacent to the cup-shaped bottom 15 c of the lower second locking device 9 in FIG. 8 . If the actuating part 29 a belonging to the upper locking device 9 is subsequently rotated axially, the locking arms 31 belonging to the upper rotating part 29 are situated behind the remaining locking projections 41 , which are formed by the remaining bottom sections in the bottom 15 b of the lower locking device 9 in FIG. 8 . These locking projections 41 are the remaining material sections in the bottom 15 b which are in each case formed in the direction of rotation about the central axis 25 with a rotational offset with respect to the cross-shaped cutouts 23 .
Since, as mentioned, the cutout 23 is designed to be larger in dimension than the locking elements 29 c which can be moved through it, and also, in the rotating or locking position otherwise, the ends of the locking elements 29 b terminate with a radial spacing in front of the boundary wall 15 a of the base part or fixed part 15 interacting therewith, a sufficient compensation margin is ensured in order for example to compensate for tolerance errors when fixedly connecting two containers one on top of the other.
It is also preferred for the underside of these locking projections 41 of the bottom 15 b and/or the adjacent bearing surface of the locking arms 31 to be roof-shaped in cross section, so that with increasing rotating movement from the neutral starting position, an increasingly greater clamping action is produced between the adjusting member 29 of one locking device 9 and the corresponding locking projections 41 in the bottom 15 b of the respective second locking device 9 interacting therewith.
FIG. 9 shows the locking arms 31 which are slightly roof-shaped in cross section or provided with a preferably central, radially extending, slightly rib-shaped elevation 42 , and FIG. 10 shows a top view of the empty cup-shaped housing or fixed part 15 without inserted adjusting member or rotating part 29 , with the result that the corresponding slightly groove-shaped depression 43 can be discerned particularly clearly here. This affords a bayonet-type locking mechanism, specifically if, in the final locking position, the for example slightly rib-shaped or gable-shaped elevations or projections 42 on a respective locking arm 31 then engage thus in the corresponding depressions 43 on the inner side of the bottom 15 b of the cup-shaped housing cover 9 a of the respective second locking device. Since the rotating part is provided with a gripping rib 45 or a gripping projection 45 which assists the rotary movement, it is also possible to tell directly from the orientation of this gripping projection 45 whether a locking engagement has taken place or not.
Finally, vertical depressions or vertical projections can also be formed on the inner side of the peripheral wall 15 a of the cup-shaped housing part 9 a , and these interact with corresponding vertical projections or vertical depressions on the outer periphery of the cover cap-shaped rotating part 29 and thereby also assist the bayonet-type closure mechanism. This also makes it possible for the person carrying out the locking to feel directly when the adjusting member 29 has reached the final locking position.
The exemplary embodiment has been described for that case in which the cutout 23 in the bottom 15 c is cross-shaped and the locking arms 31 are also correspondingly cross-shaped. However, it would also be conceivable in principle for the cutouts as well as the locking arms to have only a diagonal shape or bar shape.
It is also possible for the spiral spring device 35 described to be replaced by elastically deformable internal plastic arms cast integrally with the cup-shaped housing part 15 , which is preferably formed from plastic, these plastic arms exerting the desired prestressing forces on the adjusting member 29 .
An unlocking operation can again be carried out just as simply as the locking operation. Precisely that rotating part 29 which has been used for the locking operation is now once more turned back or rotated further until the locking arms 31 come to lie in the correct position with respect to the cross-shaped through opening 23 in the two bottoms 15 b situated one on top of the other. The assistance provided by the spring energy store then moves the pressed-in rotating part back again into its raised position in FIG. 6 .
The roof-shaped run-on surfaces on the locking arms 31 or otherwise obliquely formed or wedge-shaped run-on surfaces make it possible, with increasing rotating movement, to produce increasingly greater clamping forces directed axially towards one another between the two interacting locking devices 9 . Each of the two locking devices 9 is in this case firmly anchored on the associated item of furniture, for example on a bottom board 1 c and a top board 1 c situated below the latter. Since the flange-shaped peripheral edge 15 c in each case comes to lie on the opposite inner side of the container, none of the two locking devices can be removed from its bore in the associated shelf board even when locking forces are to be directed towards one another with ever increasing intensity. Each of the two locking devices 9 is in this case held on the associated shelf board by the flange-shaped edge.
While the technology herein has been described in connection with exemplary illustrative non-limiting implementations, the invention is not to be limited by the disclosure. The invention is intended to be defined by the claims and to cover all corresponding and equivalent arrangements whether or not specifically disclosed herein. | An improved locking device is essentially characterized by the following features: at least two recessed sections extend radially outwards from the central axis and are arranged at regular angular intervals from one another, a setting member or rotary member is provided in the inside of the pot-like or housing-like fixed element; the rotary member comprises an actuation portion with a locking element which is axially offset in the direction of the base; the locking element has a structure provided with locking arms which project radially outwards, so that the thus designed locking element can be axially inserted through the recess. | 5 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of applicant's co-pending application Ser. No. 14/510,014 filed Oct. 8, 2014 the entire contents of which is hereby expressly incorporated by reference herein.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
Not Applicable
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC
Not Applicable
BACKGROUND OF THE INVENTION
Field of the Invention
This invention relates to improvements in a device to carrying elongated objects. More particularly, the present Sling Carrier for Skis, Snowboard and Boots creates a method to carry skis and/or snowboard with boots. The sling carrier provides full mobility for the person carrying the sporting equipment.
Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
For many people that participate in outdoor winter sports, must carry their equipment from a car or ski rental location to the lift line. When a person carries the equipment to the ski lift, the person must carry the equipment to the ski lift and then the person must place the equipment onto themselves for skiing or snowboarding. Most outdoor winter athletes either ski or snowboard, but some of these athletes perform both sports and must carry a large amount of equipment to the ski lift or to a place where instruction will take place.
There are a number of different ways to carry ski and snowboard equipment. Without any external carrying equipment the person generally walks with the boots on and carries the ski/snowboard and possibly poles. A second alternative was to have some sort of external device that allows a person to carry the ski or snowboard equipment. There are a large number of variation for carrying the equipment in one hand or on their body. A number of patents and or publications have been made to address these issues. Exemplary examples of patents and or publication that try to address this/these problem(s) are identified and discussed below.
U.S. Pat. No. 5,383,587 issue to Gary L. Carpenter issued on Jan. 24, 1995 to Gary L. Carpenter discloses a Device for Carrying Elongated Ski Equipment. This patent has a pocket where the end of the skies are placed, and a strap that connects from the pocket to an upper end of the skies. The strap is placed over a shoulder so the skies are slung from behind the person and under a shoulder to a position in front of the person and must be carried with at least one hand. With this configuration the person can't bend down or forward without the skies touching the ground. The patent further does not allow the person to transport the ski boots with the skies because the ski boots will occupy an area of the person transporting the equipment.
U.S. Pat. No. 6,672,495 issued on Jan. 6, 2004 discloses a Bifurcated Carrier Pack for Transporting Recreational Equipment. The patent allows the person to transport a snowboard across the back of the user. With this embodiment the person can bend over, but the orientation of the snowboard makes it difficult to move through a door, and the straps make transportation of the boots difficult. The equipment further does not allow for transportation of skies.
U.S. Publication 2007/0210570 that was published on Sep. 13, 2007 for Jasper C. Erichsen discloses a Ski-Carrier. This publication is for an extendable belt mounted pocket. The pocket is secured onto a belt that holds the pants of a user. When a user wants to transport their skies they extend a pocket and slide the end of the skies into the pocket to support one end of the skies and holds the free end of the skies. Due to the orientation of the skies, the invention does not allow for transportation of the boots with the skies.
U.S. Publication 2010/0206930 that was published on Aug. 19, 2010 for Andrew Jason Sims discloses a Ski and Snowboard Sling-belt. The belt slings the snowboard diagonally across the back of the user. While this patent allows for transportation of ski equipment it only allows for transportation of skies or a snowboard. After transportation the invention does not have a pocket or pouch to transport the carrier after use.
What is needed is a transportation device for a skies and/or snowboard along with the poles and boots. The transportation mechanism should further provide a storage mechanism for the transportation equipment. This document provides a solution.
BRIEF SUMMARY OF THE INVENTION
It is an object of the sling carrier for skis, snowboard and boots to be able to carry the skies and or snowboard across the back of the wearer. The ability to sling the equipment over the back of a user allows the user to have full mobility walk. A user can tighten the sling to adjust the location of the equipment in their back. Having the equipment supported on their back allows the user to walk in a more balanced stance and the user just needs to bend forward or backward to accommodate the load or the terrain.
It is an object of the sling carrier for skis, snowboard and boots to include a pocket for transportation of the skies and or snowboard. It is also a function of the carrier for the pocket to be used to store the transportation equipment and therefore allow the user to easily transport the equipment after the skies and or snowboard have been transported.
It is an object of the sling carrier for skis, snowboard and boots to be used for transportation of all the unique ski equipment. Along with the skies, one embodiment includes transportation of the ski poles and the boots. All of these pieces of equipment are slung over the back of the user and essentially leaves the hands free for paying for lift tickets, food or other items. This configuration also makes it possible for a person without limbs to transport the ski equipment by themselves, without requiring an additional person to transport the ski equipment.
It is an object of the sling carrier for skis, snowboard and boots to be used transportation of all the unique snowboard equipment. Along with the snowboard, one embodiment includes transportation of the snowboard and the boots. All of these pieces of equipment are slung over the back of the user and essentially leaves the hands free for paying for lift tickets, food or other items. This configuration also makes it possible for a person without limbs to transport the ski equipment by themselves, without requiring an additional person to transport the ski equipment.
It is another object of the sling carrier for skis, snowboard and boots to be used for transportation of all the unique ski equipment for a person that both skies and snowboards. Along with the skies and snowboard this embodiment includes transportation of the ski, snowboard, poles and either sets of boots. All of these pieces of equipment are slung over the back of the user and essentially leaves the hands free for paying for lift tickets, food or other items. This configuration also makes it possible for a person without limbs to transport the ski equipment by themselves, without requiring an additional person to transport the ski equipment.
It is still another object of the sling carrier for skis, snowboard and boots to use adjustable buckles to connect straps together. Buckles allow the user to just “squeeze” elements together to release the straps. For connecting elements together the user just pushes the parts together. This is especially important when it is cold and the user's fingers and hands are cold. This is also superior to hook-and-loop fasteners that become brittle and can become clogged with ice and snow thereby rendering them non-functional in cold weather.
Various objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
FIG. 1 shows a sling carrier for skies with attached boots.
FIG. 2 shows a view of the components used in the sling carrier for skies.
FIG. 3 shows a view of the attachment of the ski poles.
FIG. 4 shows the top of the skies being secured.
FIG. 5 shows the bottom of the skies entering the pouch.
FIG. 6 shows the top of the poles being secured to the skies.
FIG. 7 shows positioning the D-ring on the bound skies.
FIG. 8 shows securing the adjustable binding strap on the skies.
FIG. 9 shows one embodiment of binding the bottom of the skies.
FIG. 10 shows the bottom of the poles being secured to the skies.
FIG. 11 shows pouch being secured to the opposing side of the sling.
FIG. 12 shows the pouch secured over a shoulder of a user.
FIG. 13 shows a sling carrier with a snowboard and snowboard boots.
FIG. 14 shows the components used in the sling carrier for a snowboard.
FIG. 15 shows a snowboard being secured into the pouch and the sling.
FIG. 16 shows the snowboard pouch being carried on the back of a user.
FIG. 17 shows a sling carrier for skis, snowboard and boots.
FIG. 18 shows the carrier without the ski equipment being carried as a backpack.
FIG. 19 shows the components used to carry skies and a snowboard.
FIG. 20 shows the snowboard in the pouch with the skies being inserted.
FIG. 21 shows the top end of the poles being secured to the skies and snowboard.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a sling carrier for skies with attached boots. In this figure the back of the user 39 is shown with the ski equipment slung over the back of the user in a diagonal orientation. In this orientation the user can bend forward and can walk with the weight of the equipment fairly evenly distributed on the user 39 . The ski boots 48 and 49 are secured in the ski bindings 47 , thereby no additional securing mechanism is required to retain the ski boots 48 and 49 . While the ski boots 48 and 49 are shown secured into the ski bindings, the user can wear the ski boots 48 and 49 on their feet or can transport them on the skis as they transport the skies and ski poles slung over the back of the user.
The curved end of the skies 42 and 43 are secured together with an upper ski strap 60 that both secures the skies 42 and 43 together and provides an upper connection for a front sling (not shown in this figure). The upper end of the poles 46 and 47 (obscured in this figure) are connected together with an upper pole strap 30 that is secured to a “D” ring (obscured in this figure) that is secured around the skis, in this case, skis 42 and 43 . The upper pole strap 30 is retained on the poles because the top of the ski poles include an enlarged top 44 to the hand grip portion of the pole(s). The flat under sides of the skies rest together and the bottom end of the ski poles are secured to the lower end of the skies 42 and 43 with a lower ski and pole strap 90 / 100 . The flat end of the skies 42 and 43 and secured into a pouch 80 .
FIG. 2 shows a view of the components used in the sling carrier for skies. These are the components that are used to transport the skies, boots and pole. The lower ski and pole straps 90 and 100 can be placed within the ski pouch 80 and all the components can be carried by the user as a complete unit. This will be shown and described in other figures herein.
The sling strap 50 has a separable buckle 53 with a male and a female clasp that allows a user to separate the two parts, 51 and 52 , of the sling strap 50 . The separable buckle 53 further includes an adjustment mechanism to alter the overall length of the sling strap to fit the geometry of a user to adjust the location of the equipment on the back of a user. On the opposing sides of the buckle 53 there are separate lengths of straps 51 and 52 . Each of these lengths of straps terminate with operable clasps 54 and 55 . The clasps 54 and 55 , along with the buckle 53 are designed to allow an operator to connect and disconnect the components in freezing condition and with limited dexterity caused by gloves and or cold conditions.
The upper ski strap 60 has a central male clasp 63 that mates or connects into a complimentary female clasp 65 . An “O” or “D” ring 64 is positioned between the male 63 and the female 65 clasps. The ring 64 allows for connection of one of the operable clasps 54 or 55 on the sling strap 50 . A free end 62 of the strap 61 allows for a user to grasp to tighten a grip on skies placed in the strap between the male 63 and the female 65 clasps. The strap 60 can also include an alarm, combination lock or other anti-theft device 66 . It is also contemplated that the male 63 and female clasps 65 can include a key lock or a combination lock.
The ski pouch 80 is essentially a pouch with an opening where the flat portion of the skies are placed to secure the flat end of the skies. The ski pouch 80 has a top flap that wraps around the opening to secure any contents within the pouch. The ski pouch 80 is shown with the lower ski strap components 90 and 100 secured to the ski pouch 80 .
The lower pole strap components 90 and 100 are snapped 93 and 103 onto the ski pouch 80 . Lower pole strap component 90 has a snap 93 at a first end with a male clasp 94 and a free length of strap material 91 with a buckle 92 . A “D” ring 95 is secured to the front flap of the ski pouch 80 . The lower pole strap component 100 also snaps to the ski pouch 80 and has a female buckle 101 . While snaps are one preferred closure embodiment, other closure types are contemplated, including but not limited to, hook and loop, magnetic closure, slots and rotating clasps.
An alternate embodiment of the straps is shown with the strap having an elongated central section 30 with an S-biner having two clip areas 32 and 33 . The other end of the strap 30 has a turnbuckle with a clasp 31 . Another contemplated retaining device is the strap with a ratchet clamp 97 that ratchets against the one-way teeth 96 to tighten and retain the strap 90 on skies. This strap has a “D” ring 98 .
FIG. 3 shows a view of the attachment of the ski poles 46 and 47 . The ski poles 46 and 47 are secured by using the pole strap 30 that has two lengths of strap material 72 and 74 with an operable clasp 73 located at an equal distance between two separate “D” ring 71 and 75 . To install the ski poles 46 and 47 onto the pole strap 30 a portion of the strap material, 72 or 74 is looped 76 and passed through the respective “D” ring 71 or 75 and the hand grip 44 or 45 of the ski pole is passed through the loop. The loop is then tightened to secure the hand grip 45 of the ski pole.
FIG. 4 shows the top of the skies being secured. Because current skies 42 & 43 are parabolic in shape, the upper ski strap 60 can be secured at a narrow portion of the skies 42 & 43 . The free end 62 of the strap 60 can be pulled to tighten the strap 60 in the buckle 63 and then moved 86 up to the wider portion of the skies 42 & 43 to increase the binding of the strap 60 on the skies 42 & 43 .
FIG. 5 shows the bottom of the skies 42 & 43 entering 87 into the open 88 end of the pouch 80 . A backing lip 85 extends around the back of the pocket to provide a flat surface that sits on the flat surface of the ski. The end of the skies 42 & 43 are then seated into the pocket 80 . The flap portion 85 of the pocket 80 is brought along the back side of the skies 42 & 43 . The ski pouch 80 has a number of snaps 82 , 83 and 84 for securing some of the straps, in particular the lower pole strap 90 / 100 that wraps around the pouch 80 and previously shown.
FIG. 6 shows the top of the poles 46 and 47 being secured to the skies 42 . The ski poles 46 and 47 have hand grips 44 and 45 respectively where the upper pole strap 72 is secured. The clasp 73 in the center of the pole strap 72 is secured to the ring 64 on the upper ski strap 60 and then the upper pole strap 72 is brought between the curved tips of the skies for stability. The clasp 54 on the lower sling strap 52 is also connected to the ring 64 on the upper strap 60 . It is important for the ring 64 to be positioned at the side of the skies to allow the apparatus to be slung diagonally across the back of a user.
FIG. 7 shows positioning the D-ring 64 on the bound skies 42 . The strap 60 holds the skies 42 tightly together. The strap is installed and tightened on the skies 42 such that the D-ring 64 is positioned on the side of the skies 42 . This allows the skies to be strapped over the back of the user and reduces the edges of the skies being in contact with the user.
FIG. 8 shows securing the adjustable binding strap 90 on the skies 42 . This binding strap 90 has a plurality of saw tooth teeth 96 . The teeth 96 engage into a ratcheting mechanism 97 that pulls on the teeth 96 to tighten the strap 90 onto the skies 42 to hold the skies within the strap 90 .
FIG. 9 shows one embodiment of binding the bottom of the skies 42 with ski poles 46 and 47 . The skies 42 are shown with securing strap 90 within the storage pouch 80 . The strap 90 secures the skies 42 and the poles 46 , 47 as a collective group.
FIG. 10 shows the bottom of the poles being secured to the skies. At this location the end of the ski poles 46 and 47 are shown secured to the bottom straight end of the skies 42 . The lower straps 90 / 100 secure all the skies and poles together to prevent undesirable movement while they are being transported.
FIG. 11 shows pouch being secured to the opposing side of the sling strap 51 . The lower end 51 of the sling strap has a clasp 55 that connects to the “D” ring 87 on the flap 85 of the pouch 80 . The flat end of the skies 42 and 43 are shown in the pouch 80 . The snap 86 can be secured to one of the snaps 86 on the front of the pouch 80 . While snaps are one preferred closure embodiment, other closure types are contemplated, including but not limited to, hook and loop, magnetic closure, slots and rotating clasps.
The ski poles 46 and 47 are shown secured to the skies 42 and 43 with the lower ski and pole strap 90 / 100 is wrapped around both the skies and both of the poles. Once both ends of the sling strap 50 have been secured with the clasp 54 in the “D” ring 64 (at the other end of strap 51 ) and the “D” ring 87 with clasp 55 of the ski pouch 80 , the user can place the sling 50 over their head and shoulder. Once the user is wearing the sling, the user can adjust the length of the sling 50 to set the preferred location of the sling on the user. To quickly remove the sling, a user can unbuckle the clasp or buckle 53 in the sling 50 .
FIG. 12 shows the pouch 80 secured over a shoulder of a user 39 . When the pouch 80 is not being used to transport ski equipment, the remaining straps are placed into the pouch 80 . This view shows the clasp 53 of the sling 51 and 52 . The clasps 54 and 55 are secured to “D” ring on the back of the pouch 80 . The front flap 85 of the pouch 80 is brought over the pouch 80 where the “D” ring 87 is held by the straps.
FIG. 13 shows a sling carrier with a snowboard 110 and snowboard boots 111 and 112 . The snowboard 110 , boots or boot bindings 111 and 112 are all carried on the back of the user 39 in a sling arrangement that allows the person 39 to easily walk and bend over because the equipment is distributed and balanced on the back of the user 39 . This further frees the hands of the user to pay for lift tickets or carry other items. The bottom of the snowboard 110 is held in a pocket 133 within a pouch 130 . The pouch 130 has a surrounding lip 134 with a raised front surface where the snowboard 110 fits inside of the pouch 130 . The front of the pouch 130 has some pockets with mechanical or magnetic snaps 135 and 136 for securing the pockets. A sling strap (not visible in this figure) connects from the pouch 130 to an upper strap 120 .
The upper strap 120 wraps around the upper portion of the snowboard 110 to secure the snowboard 110 . The upper strap has a male 121 and a female 122 buckle portion secured on the strap 120 . The “O” or “D” ring 122 is placed in the center of the width of the snowboard. An end 123 of the strap 120 allows for tightening or loosening of the strap 120 on the snowboard 110 .
FIG. 14 shows the components used in the sling carrier for a snowboard. The sling strap 50 has a separable buckle 53 with a male and a female clasp that allows a user to separate the two parts, 51 and 52 , of the sling strap 50 . The separable buckle 53 further includes an adjustment mechanism to alter the overall length of the sling strap to fit the geometry of a user to adjust the location of the equipment on the back of a user. An adjustable pad 56 is present on the strap 52 to provide a cushion and to distribute loads on the strap 50 . On the opposing sides of the buckle 53 there are separate lengths of straps 51 and 52 . Each of these lengths of straps terminate with operable clasps 54 and 55 . The clasps 54 and 55 , along with the buckle 53 are designed to allow an operator to connect and disconnect the components in freezing condition and with limited dexterity caused by gloves and or cold conditions.
The pouch 130 is configured with a square or rounded bottom to accept either end of a snowboard. The pouch 130 has a front flap 132 that closes over a pocket opening 133 where an end of a snowboard is secured therein. The flap has a “D” ring at the front of the flap for securing one end 55 of the sling strap 50 . Mechanical or magnetic snaps 137 and 138 secure the flap 132 to the front of the pouch 130 . A plurality of “D” rings and clasps 127 , 128 and 129 are located on the front and back of the pouch 130 for converting the pouch into a backpack for storage of the straps and or other personal items.
An upper snowboard strap 120 is configured to wrap around the snowboard. The inside of the upper snowboard strap 120 is reinforced or backed with leather or other equivalent material to protect the strap material from being damaged from the hard sharp edges of the snowboard. This strap 120 has a male connector 121 and a female connector 125 at opposing ends. The tail 123 can be pulled to tighten the strap 120 on the snowboard. Between the male 121 and the female 125 connectors an “O” or “D” ring is located between the strap portions 122 and 124 . The “O” or “D” ring is used to connect to the other clasp 55 on the opposing end of the sling strap 50 . Two additional strap members 140 are used to transport the pouch 130 as a backpack.
The strap members 140 are essentially the same. The straps 140 include clasps 141 and 147 on each end of the strap. The strap 140 has three section 142 , 144 and 146 . Between section 144 and 146 a “D” ring 145 is located for securing the end of the strap 144 . An adjustable buckle 143 is located to adjust the overall length of the strap 140 .
FIG. 15 shows a snowboard being secured into the pouch and the sling. First the upper strap is secured around the snowboard 110 and then buckle at the end of strap portions 122 and 124 is connected. The strap is tightened onto the snowboard 110 at a position above the top boot binding.
When the top strap is attached, the “O” or “D” ring 123 is centered in the middle of the base width wise. Snowboards also have a parabolic shape. The method for attaching the top strap 122 is to clip it around the board just above the leading (top) binding, pull the adjuster strap down nice and snug making sure the “O” or “D” 123 is centered on the base, the strap is moved up until the strap reaches the widest part of the parabolic shape making a nice and tight strap on the snowboard.
The bottom of the snowboard is slid into the pouch opening 139 to a position below the lower binding 111 . The top flap 132 is lifted to allow the clip 55 of the sling strap to connect to the “D” loop 126 . The other end of the sling strap 52 is then hooked 54 into the “O” or “D” ring 123 of the upper strap. The user can then enter into the sling strap and tighten the sling strap for the desired fit. When the board is being transported, the top strap will come into contact with the edges as it is positioned on the base. Those edges can be extremely sharp and would probably cut right through a standard nylon strap. As with the ski sling, the central buckle on the sling strap is disconnected to quickly exit from the snowboard sling carrier.
FIG. 16 shows the snowboard pouch being carried on the back of a user. When the snowboard carrier is not being used to transport the snowboard the pouch 130 can be used as a backpack. The strap members 142 are connected to the “D” ring 129 at the top of the carrier and also connected to “D” rings 158 (obscured in this view) on the back of the carrier 130 . The straps 140 can then be adjusted to the desired fit based upon the desires of the user or the physical features of the user 39 .
FIG. 17 shows a sling carrier for skis, snowboard and boots. In this embodiment a user 39 is able to carry all of the ski and snowboard equipment with a single sling carrier. The hands of the user remain free. The majority of the components have been shown and described in previous embodiments shown and described herein with the exception of the pouch 150 . The pouch has two pockets, a first pocket 151 where the snowboard 110 is inserted and a second pouch 153 where the flat ends of the skies are inserted, and the ends of the ski poles 46 and 47 are retained. The pocket 153 for the skies 42 & 43 essentially folds out perpendicular to the pocket 151 that retains the snowboard 110 . A flap 152 covers the ski retaining pocket 153 when the pocket is not being used.
FIG. 18 shows the carrier without the ski and snowboard equipment being carried as a backpack. This figure shows the other side of the flap 152 with storage pockets 154 and 155 for storage of the securing straps. The back of the flap 152 further includes a transparent window 156 for storage of a license, lift ticket etc.
When the carrier 150 is not being used to transport the skies and or snowboard the pouch 150 can be used as a backpack. The strap members 142 are connected to the “D” ring 157 at the top of the carrier and also connected to “D” rings (obscured in this view) on the back of the carrier 150 . The straps can then be adjusted to the desired fit based upon the desires of the user or the physical features of the user 39 .
FIG. 19 shows the components used to carry skies and a snowboard. The straps 50 , 30 , 120 , 140 and 190 are essentially the same as previously described. Strap 50 includes a protective sleeve 57 to reduce abrasion of the clasp 54 . Strap 190 is essentially the same as strap 120 with a slight difference in the length of the strap and strap 120 further has an additional clip that is adjacent to the female part of the buckle. The clip is secured to the upper ski strap 190 .
To assemble the skis within this storage version the curved ends of the skies are bound as previously described and the grip ends of the ski poles are bound as previously identified.
FIG. 20 shows the snowboard in the pouch with the skies being inserted. The strap 120 is secured to the snowboard 110 as previously described. The snowboard 110 is inserted into the pocket 151 of the pouch 150 . An inner pocket 153 is exposed from the pouch 150 and the flat end of the skies are inserted into the inner pocket 153 . The skies 42 and 43 are elevated, essentially parallel to the snowboard 110 .
FIG. 21 shows the top end of the poles being secured to the skies 42 & 43 and snowboard 110 . In this figure the strap 30 that retains the ski poles 46 & 47 are secured to the “D” ring of strap 190 . The “D” ring of strap 190 is connected to clip that is adjacent to the female buckle. The free end of the ski poles are the tucked into the pocket 153 . The sling strap 50 is secured to strap 120 and to the pouch 150 to allow a user to lift all the equipment onto their back for transportation.
While specific materials of leather, nylon and “O” or “D” rings and buckles have been identified in the application, it should be obvious to one skilled in the art that future progression of the carriers can include alternative materials and construction that provide the same or superior functionality.
Thus, specific embodiments of a sling carrier for skis, snowboard and boots has been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. | Improvements in a sling carrier for skis, snowboard and boots to be able to carry the skies and or snowboard across the back of the wearer is disclosed. The ability to sling the equipment over the back of a user allows the user to have full mobility walk. A user can tighten the sling to adjust the location of the equipment in their back. Having the equipment supported on their back allows the user to walk in a more balanced stance and the user just needs to bend forward or backward to accommodate the load or the terrain. The carrier uses pockets for the equipment and for transportation of the carrier equipment. This also leave the hand of the user free while transporting equipment. The carrier uses Buckles that allow the user to just “squeeze” elements together to release the straps. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent application Ser. No. 15/007,784, filed Jan. 27, 2016, which is a continuation of U.S. patent application Ser. No. 14/996,544 filed Jan. 15, 2016, which is a continuation-in-part of U.S. patent application Ser. No. 14/795,931, filed Jul. 10, 2015, which is a continuation-in-part of U.S. patent application Ser. No. 14/248,386, filed Apr. 4, 2014, which is a continuation-in-part of International Application No. PCT/US2013/020724 filed Jan. 9, 2013 which claims priority to U.S. Provisional Application No. 61/592,643, filed Jan. 31, 2012. U.S. patent application Ser. No. 14/248,386 further claims priority to U.S. Provisional Application No. 61/884,660 filed Sep. 30, 2013.
BACKGROUND
[0002] This application relates to the design of a turbine which can be operated to produce noise to which human hearing is less sensitive.
[0003] Gas turbine engines are known, and typically include a fan delivering air into a compressor. The air is compressed in the compressor and delivered downstream into a combustor section where it was mixed with fuel and ignited. Products of this combustion pass downstream over turbine rotors, driving the turbine rotors to rotate.
[0004] Typically, there is a high pressure turbine rotor, and a low pressure turbine rotor. Each of the turbine rotors includes a number of rows of turbine blades which rotate with the rotor. Typically interspersed between the rows of turbine blades are vanes.
[0005] The low pressure turbine can be a significant noise source, as noise is produced by fluid dynamic interaction between the blade rows and the vane rows. These interactions produce tones at a blade passage frequency of each of the low pressure turbine stages, and their harmonics.
[0006] The noise can often be in a frequency range to which humans are very sensitive. To mitigate this problem, in the past, a vane-to-blade ratio of the fan drive turbine has been controlled to be above a certain number. As an example, a vane-to-blade ratio may be selected to be 1.5 or greater, to prevent a fundamental blade passage tone from propagating to the far field. This is known as acoustic “cut-off.”
[0007] However, acoustically cut-off designs may come at the expense of increased weight and reduced aerodynamic efficiency. Stated another way, if limited to a particular vane to blade ratio, the designer may be restricted from selecting such a ratio based upon other characteristics of the intended engine.
[0008] Historically, the low pressure turbine has driven both a low pressure compressor section and a fan section. More recently, a gear reduction has been provided such that the fan and low pressure compressor can be driven at different speeds.
SUMMARY
[0009] In a featured embodiment, a gas turbine engine has a fan section including a fan having at least one fan blade. A low fan pressure ratio is less than about 1.45, wherein the low fan pressure ratio is measured across a fan blade alone. A turbine section has a first turbine and a second turbine. A gear reduction is between the fan and the first turbine, the gear reduction including an epicycle gear train having a gear reduction ratio of greater than about 2.5:1, and the gear reduction being configured to receive an input from the first turbine and to turn the fan at a lower speed than the first turbine in operation. The first turbine includes a pressure ratio greater than about 5:1, the first turbine including an inlet having an inlet pressure, and an outlet that is prior to any exhaust nozzle and having an outlet pressure. The pressure ratio of the first turbine is a ratio of the inlet pressure to the outlet pressure. The first turbine further includes a number of turbine blades in each of a plurality of rows of the first turbine. The first turbine blades operate at least some of the time at a rotational speed, and the number of blades and the rotational speed are such that the following formula holds true for at least one of the blade rows of the first turbine: (number of blades×speed)/60≧5500. The rotational speed is an approach speed in revolutions per minute, taken at an approach certification point as defined in Part 36 of the Federal Airworthiness Regulations. The gas turbine engine is rated to produce 15,000 pounds of thrust or more.
[0010] In another embodiment according to the previous embodiment, the formula results in a number greater than 6000.
[0011] In another embodiment according to any of the previous embodiments, the formula results in a number less than or equal to about 10000.
[0012] In another embodiment according to any of the previous embodiments, the formula results in a number less than 7000.
[0013] In another embodiment according to any of the previous embodiments, the formula holds true for a majority of the blade rows of the first turbine.
[0014] In another embodiment according to any of the previous embodiments, the formula results in a number greater than 6000.
[0015] In another embodiment according to any of the previous embodiments, the formula results in a number less than or equal to about 10000.
[0016] In another embodiment according to any of the previous embodiments, the formula results in a number less than 7000.
[0017] In another embodiment according to any of the previous embodiments, a mid-turbine frame is arranged between the second turbine and the first turbine.
[0018] In another embodiment according to any of the previous embodiments, a compressor section is configured to drive air along a core flowpath, and a plurality of bearing systems configured to support the first turbine and the second turbine, wherein the mid-turbine frame includes airfoils positioned in the core flowpath and is configured to support at least one of the bearing systems.
[0019] In another embodiment according to any of the previous embodiments, the second turbine has two stages.
[0020] In another embodiment according to any of the previous embodiments, a first compressor is included, and a shaft configured to be driven by the first turbine. The gear reduction is arranged intermediate the first compressor and the shaft.
[0021] In another embodiment according to any of the previous embodiments, the second turbine has two stages.
[0022] In another embodiment according to any of the previous embodiments, a bypass ratio is greater than ten (10). The fan has a low corrected fan tip speed less than about 1150 ft/second, wherein the low corrected fan tip speed is an actual fan tip speed in ft/second at an ambient temperature divided by [(Tambient ° R)/(518.7° R)] 0.5 .
[0023] In another embodiment according to any of the previous embodiments, the fan section is designed for cruise.
[0024] In another embodiment according to any of the previous embodiments, the formula holds true for all of the blade rows of the first turbine.
[0025] In another embodiment according to any of the previous embodiments, the formula results in a number greater than 6000.
[0026] In another embodiment according to any of the previous embodiments, the formula results in a number less than or equal to about 10000.
[0027] In another embodiment according to any of the previous embodiments, the formula results in a number less than 7000.
[0028] In another embodiment according to any of the previous embodiments, the formula does not hold true for all of the blade rows of the first turbine.
[0029] In another featured embodiment, a gas turbine engine has a fan section including a fan having at least one fan blade. A low fan pressure ratio is less than about 1.45, wherein the low fan pressure ratio is measured across a fan blade alone. A turbine section has a first turbine and a second turbine. A gear reduction is between the fan and the first turbine, the gear reduction including an epicycle gear train having a gear reduction ratio of greater than about 2.5:1, and the gear reduction being configured to receive an input from the first turbine and to turn the fan at a lower speed than the first turbine in operation. The first turbine includes a pressure ratio greater than about 5:1. The first turbine includes an inlet having an inlet pressure, and an outlet that is prior to any exhaust nozzle and having an outlet pressure. The pressure ratio of the first turbine is a ratio of the inlet pressure to the outlet pressure. The first turbine further includes a number of turbine blades in each of a plurality of rows of the first turbine, and the turbine blades of the first turbine operating at least some of the time at a rotational speed, and the number of blades and the rotational speed being such that the following formula holds true for at least one of the blade rows of the first turbine: (number of blades×speed)/60≧5500. The rotational speed is a cruise speed in revolutions per minute, taken at a cruise certification point. The gas turbine engine is rated to produce 15,000 pounds of thrust or more.
[0030] In another embodiment according to the previous embodiment, the formula results in a number less than 7000.
[0031] In another embodiment according to any of the previous embodiments, the formula holds true for a majority of the blade rows of the first turbine.
[0032] In another embodiment according to any of the previous embodiments, the formula results in a number less than 7000.
[0033] In another embodiment according to any of the previous embodiments, a mid-turbine frame is arranged between the second turbine and the first turbine.
[0034] In another embodiment according to any of the previous embodiments, a compressor section is configured to drive air along a core flowpath, and a plurality of bearing systems is configured to support the first turbine and the second turbine, wherein the mid-turbine frame includes airfoils positioned in the core flowpath and is configured to support at least one of the bearing systems.
[0035] In another embodiment according to any of the previous embodiments, a first compressor is included, and a shaft configured to be driven by the first turbine. The gear reduction is arranged intermediate the first compressor and the shaft.
[0036] In another embodiment according to any of the previous embodiments, a bypass ratio is greater than ten (10), wherein the fan section is designed for cruise, and wherein the fan has a low corrected fan tip speed less than about 1150 ft/second, wherein the low corrected fan tip speed is an actual fan tip speed in ft/second at an ambient temperature divided by [(Tambient ° R)/(518.7° R)] 0.5 .
[0037] In another embodiment according to any of the previous embodiments, the formula holds true for all of the blade rows of the first turbine.
[0038] In another featured embodiment, a turbine section has a low pressure turbine including a pressure ratio greater than about 5:1. The low pressure turbine includes an inlet having an inlet pressure, and an outlet that is prior to any exhaust nozzle and having an outlet pressure. The pressure ratio of the low pressure turbine is a ratio of the inlet pressure to the outlet pressure. The low pressure turbine further includes a number of turbine blades in each of a plurality of rows of the low pressure turbine, a majority of the turbine blades of the low pressure turbine operating at least some of the time at a rotational speed, and the number of blades and the rotational speed being such that the following formula holds true for at least one of the blade rows of the low pressure turbine: (number of blades×speed)/60≧5500. The rotational speed is an approach speed in revolutions per minute, taken at an approach certification point as defined in Part 36 of the Federal Airworthiness Regulations.
[0039] Although the different examples have the specific components shown in the illustrations, embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from one of the examples in combination with features or components from another one of the examples.
[0040] These and other features disclosed herein can be best understood from the following specification and drawings, the following of which is a brief description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] FIG. 1 shows a gas turbine engine.
[0042] FIG. 2 shows another embodiment.
[0043] FIG. 3 shows yet another embodiment.
DETAILED DESCRIPTION
[0044] FIG. 1 schematically illustrates a gas turbine engine 20 . The gas turbine engine 20 is disclosed herein as a two-spool turbofan that generally incorporates a fan section 22 , a compressor section 24 , a combustor section 26 and a turbine section 28 . Alternative engines might include an augmentor section (not shown), or an intermediate spool, among other systems or features. The fan section 22 drives air along a bypass flowpath B while the compressor section 24 drives air along a core flowpath C for compression and communication into the combustor section 26 then expansion through the turbine section 28 . Although depicted as a two-spool turbofan gas turbine engine in the disclosed non-limiting embodiment, it should be understood that the concepts described herein are not limited to use with two-spool turbofans as the teachings may be applied to other types of turbine engines including three-spool architectures.
[0045] The engine 20 generally includes a low speed spool 30 and a high speed spool 32 mounted for rotation about an engine central longitudinal axis A relative to an engine static structure 36 via several bearing systems 38 . It should be understood that various bearing systems 38 at various locations may alternatively or additionally be provided.
[0046] The low speed spool 30 generally includes an inner shaft 40 that interconnects a fan 42 , a low pressure compressor 44 and a low pressure turbine 46 . The inner shaft 40 is connected to the fan 42 through a geared architecture 48 to drive the fan 42 at a lower speed than the low speed spool 30 . The high speed spool 32 includes an outer shaft 50 that interconnects a high pressure compressor 52 and high pressure turbine 54 . A combustor 56 is arranged between the high pressure compressor 52 and the high pressure turbine 54 . A mid-turbine frame 57 of the engine static structure 36 is arranged generally between the high pressure turbine 54 and the low pressure turbine 46 . The mid-turbine frame 57 further supports bearing systems 38 in the turbine section 28 . The inner shaft 40 and the outer shaft 50 are concentric and rotate via bearing systems 38 about the engine central longitudinal axis A which is collinear with their longitudinal axes.
[0047] The core airflow is compressed by the low pressure compressor 44 then the high pressure compressor 52 , mixed and burned with fuel in the combustor 56 , then expanded over the high pressure turbine 54 and low pressure turbine 46 . The mid-turbine frame 57 includes airfoils 59 which are in the core airflow path. The turbines 46 , 54 rotationally drive the respective low speed spool 30 and high speed spool 32 in response to the expansion.
[0048] The terms “low” and “high” as applied to speed or pressure for the spools, compressors and turbines are of course relative to each other. That is, the low speed spool operates at a lower speed than the high speed spool, and the low pressure sections operate at lower pressure than the high pressures sections.
[0049] The engine 20 in one example is a high-bypass geared aircraft engine. In a further example, the engine 20 bypass ratio is greater than about six (6), with an example embodiment being greater than ten (10), the geared architecture 48 is an epicyclic gear train, such as a star system, a planetary gear system or other gear system, with a gear reduction ratio of greater than about 2.3:1 or greater than about 2.5:1. In some embodiments, the bypass ratio is less than about thirty (30), or more narrowly less than about twenty (20). In embodiments, the gear reduction ratio is less than about 5.0, or less than about 4.0. In one disclosed embodiment, the engine 20 bypass ratio is greater than about ten (10:1), the fan diameter is significantly larger than that of the low pressure compressor 44 , and the low pressure turbine 46 has a pressure ratio that is greater than about 5:1. The low pressure turbine 46 pressure ratio is a ratio of the pressure measured at inlet of low pressure turbine 46 to the pressure at the outlet of the low pressure turbine 46 (prior to an exhaust nozzle). It should be understood, however, that the above parameters are only exemplary of one embodiment of a geared architecture engine and that the present invention is applicable to other gas turbine engines including direct drive turbofans.
[0050] A significant amount of thrust is provided by the bypass flow B due to the high bypass ratio. The fan section 22 of the engine 20 is designed for a particular flight condition—typically cruise at about 0.8 Mach and about 35,000 feet. The flight condition of 0.8 Mach and 35,000 ft, with the engine at its best fuel consumption—also known as “bucket cruise Thrust Specific Fuel Consumption (‘TSFC’)”—is the industry standard parameter of lbm of fuel being burned divided by lbf of thrust the engine produces at that minimum point. “Low fan pressure ratio” is the pressure ratio across the fan blade alone, without a Fan Exit Guide Vane (“FEGV”) system. The low fan pressure ratio as disclosed herein according to one non-limiting embodiment is less than about 1.50 and, in some embodiments, is less than about 1.45. “Low corrected fan tip speed” is the actual fan tip speed in ft/sec divided by an industry standard temperature correction of [(Tambient deg R)/518.7)̂0.5]. The “Low corrected fan tip speed” as disclosed herein according to one non-limiting embodiment is less than about 1150 ft/second.
[0051] The use of the gear reduction between the low pressure turbine spool and the fan allows an increase of speed to the low pressure compressor. In the past, the speed of the low pressure turbine has been somewhat limited in that the fan speed cannot be unduly high. The maximum fan speed is at its outer tip, and in larger engines, the fan diameter is much larger than it may be in lower power engines. However, a gear reduction may be used to free the designer from compromising low pressure turbine speed in order not to have unduly high fan speeds.
[0052] It has been discovered that a careful design between the number of rotating blades, and the rotational speed of the low pressure turbine can be selected to result in noise frequencies that are less sensitive to human hearing.
[0053] A formula has been developed as follows:
[0000] (blade count×rotational speed)/(60 seconds/minute)≧4000 Hz.
[0054] That is, the number of rotating blades in any low pressure turbine stage, multiplied by the rotational speed of the low pressure turbine (in revolutions per minute), divided by 60 seconds per minute (to put the amount per second, or Hertz) should be greater than or equal to about 4000 Hz. In one embodiment, the amount is greater than or equal to about 5500 Hz. And, in another embodiment, the amount is greater than or equal to about 6000 Hz. In embodiments, the amount is less than or equal to about 10000 Hz, or more narrowly less than or equal to about 7000 Hz. A worker of ordinary skill in the art would recognize that the 60 s factor is to change revolutions per minute to Hertz, or revolutions per one second. For the purposes of this disclosure, the term “about” means ±3% of the respective quantity unless otherwise disclosed.
[0055] The operational speed of the low pressure turbine as utilized in the formula should correspond to the engine operating conditions at each noise certification point currently defined in Part 36 or the Federal Airworthiness Regulations. More particularly, the rotational speed may be taken as an approach certification point as currently defined in Part 36 of the Federal Airworthiness Regulations. For purposes of this application and its claims, the term “approach speed” equates to this certification point. In other embodiments, the rotational speed is taken as a takeoff or cruise certification point, with the terms “takeoff speed” and “cruise speed” equating to these certification points. In some embodiments, the above formula results in a number that is less than or equal to about 10000 Hz at takeoff speed. In other embodiments, the above formula results in a number that is less than or equal to about 7000 Hz at approach speed.
[0056] Although the above formula only needs to apply to one row of blades in the low pressure turbine 26 , in one embodiment, all of the rows in the low pressure turbine meet the above formula. In some embodiments, the majority of the blade rows in the low pressure turbine meet the above formula, but some perhaps may not.
[0057] This will result in operational noise to which human hearing will be less sensitive.
[0058] In embodiments, it may be that the formula can result in a range of greater than or equal to 4000 Hz, and moving higher. Thus, by carefully designing the number of blades and controlling the operational speed of the low pressure turbine (and a worker of ordinary skill in the art would recognize how to control this speed) one can assure that the noise frequencies produced by the low pressure turbine are of less concern to humans.
[0059] This invention is most applicable to jet engines rated to produce 15,000 pounds of thrust or more and with bypass ratios greater than about 8.0.
[0060] FIG. 2 shows an embodiment 200 , wherein there is a fan drive turbine 208 driving a shaft 206 to in turn drive a fan rotor 202 . A gear reduction 204 may be positioned between the fan drive turbine 208 and the fan rotor 202 . This gear reduction 204 may be structured and operate like the gear reduction disclosed above. A compressor rotor 210 is driven by an intermediate pressure turbine 212 , and a second stage compressor rotor 214 is driven by a turbine rotor 216 . A combustion section 218 is positioned intermediate the compressor rotor 214 and the turbine section 216 .
[0061] FIG. 3 shows yet another embodiment 300 wherein a fan rotor 302 and a first stage compressor 304 rotate at a common speed. The gear reduction 306 (which may be structured as disclosed above) is intermediate the compressor rotor 304 and a shaft 308 which is driven by a low pressure turbine section.
[0062] Although an embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention. | A gas turbine engine has a fan section including a fan. A turbine section has a first turbine and a second turbine. A gear reduction between the fan and the first turbine includes an epicycle gear train. The gear reduction is configured to receive an input from the first turbine and to turn the fan at a lower speed than the first turbine in operation. The first turbine further includes a number of turbine blades in each of a plurality of rows of the first turbine. The first turbine blades operate at least some of the time at a rotational speed. The number of blades and the rotational speed is such that the following formula holds true for at least one of the blade rows of the first turbine: (number of blades×speed)/60≧5500. A turbine section is also disclosed. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an EGR device for use in an engine, and more specifically relates to a constructing technique for bypassing an EGR control valve equipped with the EGR device.
2. Related Art
Conventionally, there is widely known an EGR (Exhaust Gas Recirculation) device, which refluxes a part of exhaust gas from an exhaust system to an intake system in an engine, for the purpose of reducing nitrogen dioxide (No x ) generation included in the exhaust gas. There is also well known a technique of the EGR device for the engine provided with an EGR valve for controlling a reflux volume of the EGR gas, in the EGR device.
Meanwhile, because when an engine load is increased, the temperature of the exhaust gas (the EGR gas) is generally increased, there is widely known an EGR device provided with an EGR cooler near the EGR valve, so as to reflux the high-temperature EGR gas in a high load area, and there is well-known a technique for avoiding a damage of the EGR cooler and for enhancing the safety of the EGR device, by bypassing the EGR cooler and preventing an abnormal pressure increase of the EGR cooler.
For example, JP 2004-346918 discloses a technique, which a bypass passage bypassing the EGR cooler is connected between an EGR pipe upstream of the EGR gas and an EGR pipe downstream of the EGR gas in the EGR cooler, or between an EGR pipe upstream of the EGR gas and the engine intake system in the EGR cooler, as well as which a changeover valve is mounted to a bifurcated portion between the bypass passage and the EGR pipe upstream of the EGR gas, and a manometer is attached to the upstream of the EGR gas in the changeover valve and a thermometer is attached to a refrigerant lead-out port of the EGR cooler, wherein the control means bypasses the EGR gas to the bypass passage by controlling the opening and closing of the changeover valve, when any one of the detection values by the manometer or the thermometer reaches the predefined setting value.
DISCLOSURE OF INVENTION
Problems to Be Solved By the Invention
Due to the construction disclosed in the above-mentioned patent literature, when the temperature of the EGR gas is increased due to an abnormal combustion of the engine or the like or when the back pressure to the EGR gas is increased by the clogging of the EGR cooler due to soot with long-term use, the EGR gas can be recirculated to the engine intake system by bypassing the EGR cooler, thereby being capable of preventing the damage of the EGR cooler and improving the safety of the EGR device.
However, since the EGR cooler that contributes significantly to the reduction in the No x of a diesel engine is a consumable supply, it needs to be maintained or replaced after a certain degree of duration of service, and EGR cooler requires additional coolant water introducing pipe or a cooled air introducing passage for the EGR cooler, leading to the increasing of cost. It is disadvantageous in that as the EGR gas does not go through the EGR cooler when the EGR cooler is clogged, the high-temperature EGR gas is introduced into the intake system and the combustion temperature is increased, thereby leading to the inconsiderable contribution to the reduction in the No x .
In consideration of the above-described problems, it's an object of the present invention to provide an EGR device for an engine without a cooling structure such as an EGR cooler.
Further, it's an object of the present invention to provide an EGR device for an engine that reduces NO x included into an exhaust gas in the whole operation areas, so as to correspond to the recent exhaust gas regulation.
SUMMARY OF THE INVENTION
An EGR device for an engine of the present invention comprises an EGR passage for continuously connecting an exhaust passage and an intake passage of the engine, an EGR control valve for controlling a passage area of the EGR passage, and a control means for controlling the EGR control valve. The EGR device further comprises a bypass passage for bypassing the EGR control valve and a restrictor in the bypass passage.
In the EGR device for the engine, it is preferable that a detecting means for detecting an exhaust gas temperature of the engine is provided and the detecting means is connected to the control means, wherein the control means controls the EGR control valve corresponding to the exhaust gas temperature detected by the detecting means so as to change the passage area, and the control means controls the EGR control valve so that it is totally closed, when the exhaust gas temperature is a setting value preliminarily set up or higher.
In the EGR device for the engine, it is preferable that the restrictor is provided in the bypass passage and the restrictor is a fixed restrictor.
In the EGR device for the engine, it is preferable that the restrictor is provided in the bypass passage and a means for adjusting a throttling degree of the restrictor is provided with the restrictor.
In the EGR device for the engine, it is preferable that the bypass passage is provided in a mechanism making up the EGR control valve.
In the EGR device for the engine, it is preferable that a means for adjusting the throttling degree of the restrictor is installed on the restrictor provided in the mechanism making up the EGR control valve.
Due to the EGR device for the engine of the present invention, the EGR gas can be introduced in the whole operation areas of the engine by bypassing the EGR valve having lower thermal resistance. The amount of the EGR gas can be increased or the EGR valve can be minified. The EGR gas can be introduced without involving the EGR valve even in high-load areas where the exhaust gas becomes high temperature, by providing a restrictor which can secure the minimum EGR gas for reducing the NO x in the high-load areas, thereby extending a life span of an electromagnetic device provided with the EGR valve so as to extend the life span of the whole EGR valve.
The EGR device for the engine of the present invention can set up the maximum temperature of the EGR gas flowing through the EGR control valve. When the EGR control valve is totally enclosed, due to the lower thermal conductivity of the gas, the heat is hard to be transmitted to the EGR control valve. Accordingly, the thermal resistance of the EGR control valve need not be considered, thereby eliminating the need for the EGR cooler or a particular kind of heat resistance structure.
The EGR device can be installed to the conventional intake/exhaust system, by forming the bypass in the EGR passage (the pipe making up the EGR passage).
The EGR device for the engine can have the general versatility of the engine specifications (model, size or the like), by controlling the opening degree of the restrictor.
A particular kind of thermal resistant specification in the EGR cooler conventionally provided with the upstream of the EGR control valve or the EGR control valve itself becomes unnecessary, just by replacing the EGR control valve, even in the existing EGR device, by making up the bypass in the mechanism comprising the EGR control valve.
The EGR device for the engine can have the general versatility of the engine specifications (model, size or the like), by controlling the opening degree of the restrictor. The EGR device comprised of the EGR passage, the EGR control valve or the like can be unified as an EGR unit, by providing a means for controlling the throttling degree in the mechanism making up the EGR control valve.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pattern diagram of an intake/exhaust system of an engine according to an embodiment of the present invention.
FIG. 2( a ) is a diagram illustrating a relationship between an engine torque, a rotation number and an exhaust temperature, and FIG. 2( b ) is a diagram illustrating a relationship between the engine torque, the rotation number and the opening degree of the EGR valve, when the longitudinal axis is the engine torque and the horizontal axis is the rotation number.
FIG. 3 is a partial cross sectional view in the planar view illustrating a construction of an EGR device of the engine according to the second embodiment of the present invention.
FIG. 4 is an enlarged view of an EGR valve according to the third embodiment of the present invention. FIG. 4( a ) is a planar sectional view of the EGR valve and FIG. 4( b ) is cross sectional view of the EGR valve in FIG. 4( a ) along the line A-A′.
1 engine
6 ECU (Electronic Control Unit)
9 EGR valve (EGR control valve)
23 exhaust temperature sensor (exhaust gas temperature detecting means)
24 bypass passage
25 restrictor
30 EGR device
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of an engine equipped with an EGR device for the engine according to the present invention will be described, with reference to the drawings
First, an intake/exhaust system of the engine 1 according to the first embodiment of the present invention will be described, with reference to FIG. 1 .
The air inhaled into the engine 1 is introduced from an air cleaner 2 as an air intake and is fed into an intake manifold 3 connected to the air cleaner 2 via an intake pipe 3 a . The intake manifold 3 is connected to an intake port of a cylinder head in the engine 1 , so that the air is inhaled into a cylinder.
An intake throttle 8 for controlling the inlet flow is provided in the intake pipe 3 a . The intake throttle 8 is a butterfly valve that the opening degree thereof is changed by an actuator (not shown) such as a motor provided with the inside of the intake throttle 8 . The actuator is connected to an after-mentioned ECU 6 as a control means, in which the opening/closing thereof is controlled based on a control signal from the ECU 6 .
In this regard, the construction of the intake throttle 8 is not limited to the one in the present embodiment, and the construction in which the opening/closing operation thereof can be controlled by the electric signal from the ECU 6 may be applicable.
In the cylinder, the exhaust gas that has been arbitrarily mixed and combusted with a fuel supplied by a fuel injection device is fed into an exhaust manifold 4 via an exhaust port provided with the cylinder head as outlet from the cylinder. The exhaust manifold 4 is attached on the downstream thereof with an exhaust gas filter 5 for discharging the exhaust gas in the atmosphere and the exhaust gas filter 5 is connected on the downstream thereof to a silencer (not shown).
An exhaust air heater 11 , an oxidation catalyst 12 , a soot filter 13 are incorporated into the exhaust gas filter 5 in order from the upstream of the exhaust gas filter 5 . The exhaust air heater 11 is connected via a heater relay 15 to a battery 7 , and the heater relay 15 is connected to the after-mentioned ECU 6 so that the power on/off thereof is controlled by a control signal from the ECU 6 . The exhaust air heater 11 has a facilitating effect on the actions of the oxidation catalyst 12 and the soot filter 13 disposed on the down stream thereof, by increasing the temperature of the exhaust gas.
An exhaust temperature sensor 23 as a detecting means for the exhaust gas temperature is provided near a connection between the exhaust gas filter 5 and the exhaust manifold 4 . The exhaust temperature sensor 23 is connected to the after-mentioned ECU 6 and outputs a detection value to the ECU 6 .
Next, an EGR device 30 provided with the engine 1 will be described.
The EGR device 30 is comprised of an EGR pipe 14 , an EGR valve 9 and so on.
The exhaust manifold 4 is provided in place thereof with an EGR gas exhaust 20 , and the EGR gas exhaust 20 is connected to one end of the EGR pipe 14 . The EGR pipe 14 is connected at the other end thereof to the intake manifold 3 . Thus, the EGR passage is formed so as to reflux a part of the exhaust gas as the EGR gas.
The EGR pipe 14 is attached at the midstream thereof to the EGR valve 9 for controlling a flow rate of the EGR gas. As shown in FIG. 3 , the EGR valve 9 includes two control valves 9 a , 9 a , a rod 9 b which penetrates the control valves 9 a , 9 a so as to be fixedly provided therewith in a valve casing 9 f , an actuator 9 c consisting of a motor or the like which is connected to one end of the rod 9 b and is disposed on the outside of a valve casing 9 f and so forth. The actuator 9 c is connected to the after-mentioned ECU 6 , and the actuator 9 c is operated due to a control signal from the ECU 6 so as to reciprocate the rod 9 b , so that the control valves 9 a , 9 a fixed and interlocked with the rod 9 b are opened and closed.
Depending on the opening degree of the EGR valve 9 having the above-described construction, a passage area in the EGR pipe 14 is determined, and the reflux volume of the EGR gas flowing back into the EGR device 30 is determined.
In this regard, the construction of the EGR valve 9 is not limited to the one in the present embodiment, and the construction in which the opening/closing operation thereof can be controlled by an electric signal from the ECU 6 may be applicable.
The ECU (Electronic Control Unit) 6 as a control means for controlling the operation of the engine 1 is disposed in place near the engine 1 . The ECU 6 includes a CPU, a ROM, a RAM, A/D converter, an input-output interface or the like (not shown).
The ECU 6 performs the opening/closing control for adjusting the opening degree of the intake throttle 8 by controlling the operation of the actuator provided with the intake throttle 8 and performs the opening/closing control for adjusting the opening degree of the EGR valve 9 by controlling the operation of the actuator 9 c provided with the EGR valve 9 , thereby adjusting the EGR rate of the engine 1 .
Incidentally, the ECU 6 connects a rotation number sensor for detecting a rotation number of the engine 1 , a rack actuator for adjusting the fuel injection volume, a starter for assisting the starting of the engine 1 , another sensors and an actuator resemblance when they are needed, and the ECU 6 controls them so as to optimize the operation of the engine 1 .
A solenoid device (such as the actuator) provided with the EGR valve 9 generally has a restricted thermal resistance and requires a EGR cooler or a particular heat resistance structure or the like so as to protect the EGR valve 9 , thereby leading to the increase in the cost. Especially in the engine equipped with the EGR cooler, there are problems on the cost for adding the cooling pipe or the size thereof.
Consequently, in the present embodiment, a bypass passage 24 , which is continuously connected to the intake manifold 3 from the upstream of the EGR valve 9 in the EGR pipe 14 , i.e., which bypasses the EGR valve 9 , is formed, in the conventional EGR device 30 . A restrictor 25 is provided in the bypass passage 24 , so that the EGR gas is easy to pass through the bypass passage 24 , when the amount of the EGR gas passing through the EGR valve 9 is small due to the resistance (the opening degree) of the restrictor 25 (or the EGR valve 9 is totally closed). On the contrary, when the opening degree of the EGR valve 9 is large, the EGR gas is hard to pass through the bypass passage 24 .
Specifically, the diameter of the restrictor 25 is determined so that the minimum EGR gas for the operation of the engine 1 in a high-load area where the exhaust gas temperature becomes higher can be secured through the bypass passage 24 .
One example of the functional characteristic of the exhaust gas temperature and the opening/closing control according to the opening degree of the EGR valve 9 in the present embodiment corresponding to the functional characteristic will be described, using maps that the horizontal axis and the longitudinal axis are respectively the rotation number and the output torque of the engine 1 as illustrated in FIGS. 2( a ) and ( b ).
A contour in FIG. 2( a ) shows that of the exhaust temperature of the engine 1 , it is apparent that the exhaust temperature is increased as the torque or the rotation number is higher, i.e., as the contour goes from the bottom left to the top right.
FIG. 2( b ) is an example of controlling the EGR valve 9 so as to secure the EGR volume corresponding to the exhaust gas regulation, and the contour shows the opening degree of the EGR valve. The exhaust gas temperature detected by the exhaust temperature sensor 23 , and the rotation number detected by the rotation number sensor of the engine 1 , or the opening degree of the EGR valve 9 in accordance with the output torque of the engine 1 are determined, thereby controlling the EGR valve 9 so that the NO x generation or the like do not exceed the exhaust gas regulation value.
The above-mentioned maps in FIGS. 2( a ) and ( b ) are preliminarily memorized in the ECU 6 , and the ECU 6 receives an input of the exhaust gas temperature from the exhaust temperature sensor 23 and an input of the rotation number of the engine 1 from the rotation number sensor, so as to determine the contour corresponding to the exhaust temperature referring to the map shown in FIG. 2( a ) and determine the opening degree of the EGR valve 9 corresponding to the rotation number on the contour referring to the map shown in FIG. 2( b ).
Specifically, when the exhaust temperature is beyond the heat-resistant threshold temperature (which is preliminarily memorized in the ECU 6 ) of the solenoid device or the like making up the EGR valve 9 , or when exhaust temperature is high to a certain degree and the rotation number is low, the EGR valve 9 is controlled so that it is totally closed so as to reflux the EGR gas from only the bypass passage 24 . Meanwhile, when the exhaust temperature is the heat-resistant threshold temperature or low, the opening degree of the EGR valve 9 is adjusted so that the No x generation can be controlled when needed.
In the present embodiment, the opening degree of the EGR valve 9 is controlled based on two aspects of the exhaust gas temperature and the rotation number, so as to fully exert the performance of the engine 1 even during the low rotation number and the high output, but the opening degree of the EGR valve 9 can be controlled based on one aspect of the exhaust gas temperature, and it goes without saying that the opening degree can be also controlled based on the other aspect such as the performance matching of the engine.
As seen from the above, in the EGR device 30 for the engine equipped with the EGR pipe 14 which continuously connects the exhaust manifold 4 and the intake manifold 3 , the EGR valve 9 which controls the passage area of the EGR pipe 14 , the ECU 6 which controls the EGR valve 9 , the bypass passage 24 bypassing the EGR valve 9 is provided and the bypass passage 24 is provided with the restrictor 25 , so that the EGR gas can be introduced in the whole operation areas of the engine 1 by bypassing the EGR valve 9 having the low thermal resistance. Also, the EGR gas volume can be increased or the EGR valve 9 can be minified. The EGR gas can be introduced without the EGR valve 9 even in the high-load area where the temperature of the exhaust gas is increased, by providing the restrictor 25 which can secure the minimum EGR gas for reducing the No x in the high-load area, thereby extending the life span of the electromagnetically-driven device provided with the EGR valve 9 , so as to extend the life span of the whole EGR valve 9 .
The exhaust temperature sensor 23 for detecting the exhaust gas temperature of the engine 1 is provided, and the exhaust temperature sensor 23 is connected to the ECU 6 , which controls the EGR valve 9 according to the exhaust gas temperature detected by the exhaust temperature sensor 23 and which changes the opening degree thereof so as to change the passage area, as well as when the exhaust gas temperature is the preset temperature preliminarily set up or higher, the EGR valve 9 is controlled so that it is totally closed so as to reflux the EGR gas from only the bypass passage 24 , so that the temperature of the EGR gas having lower thermal conductivity is hard to be transmitted to the EGR valve 9 . In other words, the thermal resistance of the EGR valve 9 needs not to be considered, by setting up the maximum temperature of the EGR gas flowing through the EGR valve 9 , thereby eliminating the need for the EGR cooler or a particular kind of heat resistance structure.
Because the restrictor 25 is provided in the bypass passage 24 and is a fixed restrictor, the EGR device 30 can be installed to the conventional intake/exhaust system, by making up the bypass and the restrictor in the EGR passage (the pipe).
An EGR device according to the second embodiment of the present invention will be described, with reference to FIG. 3 . In this regard, the description on the whole construction of the engine 1 in the present embodiment or the like will be omitted, since it is substantially the same as the construction in the first embodiment.
In the present embodiment, the EGR valve 9 is continuously attached to the intake manifold 3 , and the outlet of the EGR gas in the EGR valve 9 is provided so that it is directly engaged on the intake manifold 3 . The bypass passage 24 is provided so that it is continuously connected from the midstream of the EGR pipe 14 to the intake manifold 3 , and the bypass passage 24 is provided on the side of the intake manifold 3 with the restrictor 25 . The bypass passage 24 is connected to a restrictor passage 25 a provided with the side wall of the intake manifold 3 . The inner diameter of the restrictor passage 25 a is much smaller than that of the bypass passage 24 , and is determined so that the minimum EGR gas can be secured for the operation of the engine 1 in the high-load area having higher exhaust gas temperature
The restrictor passage 25 a is disposed at the midstream thereof with an adjuster 26 comprising of a bolt or the like, as a means for adjusting the throttling volume. The degree of fastening the adjuster 26 is adjusted, whereby the passage area of the restrictor passage 25 a can be adjusted. In other words, the reflux volume of the EGR gas can be adjusted when the EGR valve 9 is totally closed.
As seen from the above, the restrictor passage 25 a is provided in the bypass passage 24 , and the adjuster 26 is provided with the restrictor passage 25 a , thereby having the general versatility of the engine specifications (model, size or the like), by controlling the opening degree of the restrictor passage 25 a.
An EGR valve 9 according to the third embodiment of the present invention will be described, with reference to FIG. 4 .
In this regard, the description on the whole construction of the engine 1 in the present embodiment or the like will be omitted, since it is substantially the same as the construction in the first embodiment.
As describe above, the EGR valve 9 includes the control valves 9 a , 9 a , the rod 9 b , the actuator 9 c , the valve casing 9 f or the like, and the EGR valve mechanism is formed by assembling them. The EGF gas flows from the left side to the right side in FIG. 4 . The valve casing 9 f between an inlet 9 d for the EGR gas which is open on one side of the valve casing 9 f in the EGR valve 9 and an outlet 9 e for the EGR gas which is open on the other side thereof is provided therein with a bypass passage 24 which penetrates them, as well as the bypass passage 24 is provided therein with a restrictor 25 , which is provided with an adjuster 26 for controlling a passage area in the restrictor 25 . In other words, the bypass passage 24 , which continuously connects the EGR pipe 14 and the intake manifold 3 , is provided in the EGR valve 9 .
Herein, as the high-temperature EGR gas passes through the bypass passage 24 , it is preferable to select the position into which the bypass passage 24 is penetrated, so that the actuator 9 c or the control valves 9 a , 9 a disposed in the EGR valve 9 is not directly subjected to the EGR gas.
As described above, the bypass passage 24 is provided in the mechanism making up the EGR valve 9 , thereby eliminating the need for the particular thermal resistance specifications in the EGR cooler that has been conventionally provided on the upstream of the EGR valve, or the EGR valve itself, by replacing the EGR valve, even in the existing EGR device.
The adjuster 26 is provided with the restrictor 25 in the mechanism of the EGR valve 9 , so that the EGR device 30 can have the general versatility of the engine specifications by controlling the opening degree of the restrictor 25 . The EGR device 30 can be unified as the EGR unit, by providing the means for controlling the throttling degree in the mechanism making up the EGR valve 9 .
INDUSTRIAL APPLICABILITY
The EGR device for the engine of the present invention is widely applicable in the EGR device for use in the engine, and in particular, it is applicable in the constructing technique for bypassing the EGR control valve provided with the EGR device. | It is intended to provide an EGR device for an engine in which a cooling structure such as an EGR cooler is not required and which reduces Nox contained in the exhaust gas in the whole operation areas, so as to correspond to recent exhaust gas regulation. An EGR device 30 for an engine comprises an EGR pipe 14 for continuously connecting an exhaust manifold 4 and an intake manifold 3 of an engine 1 , an EGR valve 9 for controlling a passage area of the EGR pipe 14 , an ECU 6 for controlling the EGR valve 9 . The EGR device 30 further comprises a bypass passage 24 for bypassing the EGR valve 9 and a restrictor 25 is installed in the bypass passage 24. | 5 |
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 11/006,409, filed Dec. 6, 2004, which is a continuation of U.S. application Ser. No. 10/418,509, filed Apr. 16, 2003, now U.S. Pat. No. 6,945,903, which is a continuation of U.S. application Ser. No. 10/141,652, filed May 7, 2002, now U.S. Pat. No. 6,551,210, which is a continuation of U.S. application Ser. No. 09/695,757, filed Oct. 24, 2000, now U.S. Pat. No. 6,419,608, which issued Jul. 16, 2002. Each of the above identified applications is incorporated by reference in its entirety.
[0002] The U.S. application Ser. No. 10/418,509 is also a continuation-in-part of U.S. application Ser. No. 10/016,116, filed on Oct. 30, 2001, now U.S. Pat. No. 6,676,559, which is a continuation of U.S. application Ser. No. 09/823,620, filed Mar. 30, 2001, now U.S. Pat. No. 6,322,475, which is a continuation of U.S. application Ser. No. 09/133,284, filed Aug. 12, 1998, now U.S. Pat. No. 6,241,636, which in turn claims priority to U.S. provisional application No. 60/062,860, filed on Oct. 16, 1997; U.S. provisional application No. 60/056,045, filed on Sep. 2, 1997; U.S. provisional application No. 60/062,620, filed on Oct. 22, 1997 and U.S. provisional application No. 60/070,044 filed on Dec. 30, 1997.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The field of the invention relates to transmissions. More particularly the invention relates to continuously variable transmissions.
[0005] 2. Description of the Related Art
[0006] In order to provide an infinitely variable transmission, various traction roller transmissions in which power is transmitted through traction rollers supported in a housing between torque input and output discs have been developed. In such transmissions, the traction rollers are mounted on support structures which, when pivoted, cause the engagement of traction rollers with the torque discs in circles of varying diameters depending on the desired transmission ratio.
[0007] However, the success of these traditional solutions has been limited. For example, in U.S. Pat. No. 5,236,403 to Schievelbusch, a driving hub for a vehicle with a variable adjustable transmission ratio is disclosed. Schievelbusch teaches the use of two iris plates, one on each side of the traction rollers, to tilt the axis of rotation of each of the rollers. However, the use of iris plates can be very complicated due to the large number of parts which are required to adjust the iris plates during shifting the transmission. Another difficulty with this transmission is that it has a guide ring which is configured to be predominantly stationary in relation to each of the rollers. Since the guide ring is stationary, shifting the axis of rotation of each of the traction rollers is difficult. Yet another limitation of this design is that it requires the use of two half axles, one on each side of the rollers, to provide a gap in the middle of the two half axles. The gap is necessary because the rollers are shifted with rotating motion instead of sliding linear motion. The use of two axles is not desirable and requires a complex fastening system to prevent the axles from bending when the transmission is accidentally bumped, is as often the case when a transmission is employed in a vehicle. Yet another limitation of this design is that it does not provide for an automatic transmission.
[0008] Therefore, there is a need for a continuously variable transmission with a simpler shifting method, a single axle, and a support ring having a substantially uniform outer surface. Additionally, there is a need for an automatic traction roller transmission that is configured to shift automatically. Further, the practical commercialization of traction roller transmissions requires improvements in the reliability, ease of shifting, function and simplicity of the transmission.
SUMMARY OF THE INVENTION
[0009] The present invention includes a transmission for use in rotationally or linearly powered machines and vehicles. For example the present transmission may be used in machines such as drill presses, turbines, and food processing equipment, and vehicles such as automobiles, motorcycles, and bicycles. The transmission may, for example, be driven by a power transfer mechanism such as a sprocket, gear, pulley or lever, optionally driving a one way clutch attached at one end of the main shaft.
[0010] In one embodiment of the invention, the transmission comprises a rotatable driving member, three or more power adjusters, wherein each of the power adjusters respectively rotates about an axis of rotation that is centrally located within each of the power adjusters, a support member providing a support surface that is in frictional contact with each of the power adjusters, wherein the support member rotates about an axis that is centrally located within the support member, at least one platform for actuating axial movement of the support member and for actuating a shift in the axis of rotation of the power adjusters, wherein the platform provides a convex surface, at least one stationary support that is non-rotatable about the axis of rotation that is defined by the support member, wherein the at least one stationary support provides a concave surface, and a plurality of spindle supports, wherein each of the spindle supports are slidingly engaged with the convex surface of the platform and the concave surface of the stationary support, and wherein each of the spindle supports adjusts the axes of rotation of the power adjusters in response to the axial movement of the platform.
[0011] In another embodiment, the transmission comprises a rotatable driving member; three or more power adjusters, wherein each of the power adjusters respectively rotates about an axis of rotation that is respectively central to the power adjusters, a support member providing a support surface that is in frictional contact with each of the power adjusters, a rotatable driving member for rotating each of the power adjusters, a bearing disc having a plurality of inclined ramps for actuating the rotation of the driving member, a coiled spring for biasing the rotatable driving member against the power adjusters, at least one lock pawl ratchet, wherein the lock pawl ratchet is rigidly attached to the rotatable driving member, wherein the at least one lock pawl is operably attached to the coiled spring, and at least one lock pawl for locking the lock pawl ratchet in response to the rotatable driving member becoming disengaged from the power adjusters.
[0012] In still another embodiment, the transmission comprises a rotatable driving member, three or more power adjusters, wherein each of the power adjusters respectively rotates about an axis that is respectively central to each of the power adjusters, a support member providing a support surface that is in frictional contact with each of the power adjusters, wherein the support member rotates about an axis that is centrally located within the support member, a bearing disc having a plurality of inclined ramps for actuating the rotation of the driving member, a screw that is coaxially and rigidly attached to the rotatable driving member or the bearing disc, and a nut that, if the screw is attached to the rotatable driving member, is coaxially and rigidly attached to the bearing disc, or if the screw is rigidly attached to the bearing disc, coaxially and rigidly attached to the rotatable driving member, wherein the inclined ramps of the bearing disc have a higher lead than the screw.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a cutaway side view of the transmission of the present invention.
[0014] FIG. 2 is a partial perspective view of the transmission of FIG. 1 .
[0015] FIG. 3 is a perspective view of two stationary supports of the transmission of FIG. 1 .
[0016] FIG. 4 is a partial end, cross-sectional view of the transmission of FIG. 1 .
[0017] FIG. 5 is a perspective view of a drive disc, bearing cage, screw, and ramp bearings of the transmission of FIG. 1 .
[0018] FIG. 6 is a perspective view of a ratchet and pawl subsystem of the transmission of FIG. 1 that is used to engage and disengage the transmission.
[0019] FIG. 7 is partial perspective view of the transmission of FIG. 1 , wherein, among other things, a rotatable drive disc has been removed.
[0020] FIG. 8 is a partial perspective view of the transmission of FIG. 1 , wherein, among other things, the hub shell has been removed.
[0021] FIG. 9 is a partial perspective view of the transmission of FIG. 1 , wherein the shifting is done automatically.
[0022] FIG. 10 is a perspective view of the shifting handlegrip that is mechanically coupled to the transmission of FIG. 1 .
[0023] FIG. 11 is an end view of a thrust bearing, of the transmission shown in FIG. 1 , which is used for automatic shifting of the transmission.
[0024] FIG. 12 is an end view of the weight design of the transmission shown in FIG. 1 .
[0025] FIG. 13 is a perspective view of an alternate embodiment of the transmission bolted to a flat surface.
[0026] FIG. 14 is a cutaway side view of the transmission shown in FIG. 13 .
[0027] FIG. 15 is a schematic end view of the transmission in FIG. 1 showing the cable routing across a spacer extension of the automatic portion of the transmission.
[0028] FIG. 16 is a schematic end view of the cable routing of the transmission shown in FIG. 13 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] The following detailed description is directed to certain specific embodiments of the invention. However, the invention can be embodied in a multitude of different ways as defined and covered by the claims. In this description, reference is made to the drawings wherein like parts are designated with like numerals throughout. Furthermore, embodiments of the invention may include several novel features, no single one of which is solely responsible for its desirable attributes or which is essential to practicing the inventions herein described.
[0030] The present invention includes a continuously variable transmission that may be employed in connection with any type of machine that is in need of a transmission. For example, the transmission may be used in (i) a motorized vehicle such as an automobile, motorcycle, or watercraft, (ii) a non-motorized vehicle such as a bicycle, tricycle, scooter, exercise equipment or (iii) industrial equipment, such as a drill press, power generating equipment, or textile mill.
[0031] Referring to FIGS. 1 and 2 , a continuously variable transmission 100 is disclosed. The transmission 100 is shrouded in a hub shell 40 covered by a hub cap 67 . At the heart of the transmission 100 are three or more power adjusters 1 a, 1 b, 1 c which are spherical in shape and are circumferentially spaced equally around the centerline or axis of rotation of the transmission 100 . As seen more clearly in FIG. 2 , spindles 3 a, 3 b, 3 c are inserted through the center of the power adjusters 1 a, 1 b, 1 c to define an axis of rotation for the power adjusters 1 a, 1 b, 1 c. In FIG. 1 , the power adjuster's axis of rotation is shown in the horizontal direction. Spindle supports 2 a - f are attached perpendicular to and at the exposed ends of the spindles 3 a, 3 b, 3 c. In one embodiment, each of the spindles supports have a bore to receive one end of one of the spindles 3 a, 3 b, 3 c. The spindles 3 a, 3 b, 3 c also have spindle rollers 4 a - f coaxially and slidingly positioned over the exposed ends of the spindles 3 a, 3 b, 3 c outside of the spindle supports 2 a - f.
[0032] As the rotational axis of the power adjusters 1 a, 1 b, 1 c is changed by tilting the spindles 3 a, 3 b, 3 c, each spindle roller 4 a - f follows in a groove 6 a - f cut into a stationary support 5 a, 5 b. Referring to FIGS. 1 and 3 , the stationary supports 5 a, 5 b are generally in the form of parallel discs with an axis of rotation along the centerline of the transmission 100 . The grooves 6 a - f extend from the outer circumference of the stationary supports 5 a, 5 b towards the centerline of the transmission 100 . While the sides of the grooves 6 a - f are substantially parallel, the bottom surface of the grooves 6 a - f forms a decreasing radius as it runs towards the centerline of the transmission 100 . As the transmission 100 is shifted to a lower or higher gear by changing the rotational axes of the power adjusters 1 a, 1 b, 1 c each pair of spindle rollers 4 a - f, located on a single spindle 3 a, 3 b, 3 c, moves in opposite directions along their corresponding grooves 6 a - f.
[0033] Referring to FIGS. 1 and 3 , a centerline hole 7 a, 7 b in the stationary supports 5 a, 5 b allows the insertion of a hollow shaft 10 through both stationary supports 5 a, 5 b. Referring to FIG. 4 , in an embodiment of the invention, one or more of the stationary support holes 7 a, 7 b may have a non-cylindrical shape 14 , which fits over a corresponding non-cylindrical shape 15 along the hollow shaft 10 to prevent any relative rotation between the stationary supports 5 a, 5 b and the hollow shaft 10 . If the rigidity of the stationary supports 5 a, 5 b is insufficient, additional structure may be used to minimize any relative rotational movement or flexing of the stationary supports 5 a, 5 b. This type of movement by the stationary supports 5 a, 5 b may cause binding of the spindle rollers 4 a - f as they move along the grooves 6 a - f.
[0034] As shown in FIGS. 4 and 7 , the additional structure may take the form of spacers 8 a, 8 b, 8 c attached between the stationary supports 5 a, 5 b. The spacers 8 a, 8 b, 8 c add rigidity between the stationary supports 5 a, 5 b and, in one embodiment, are located near the outer circumference of the stationary supports 5 a, 5 b. In one embodiment, the stationary supports 5 a, 5 b are connected to the spacers 8 a, 8 b, 8 c by bolts or other fastener devices 45 a - f inserted through holes 46 a - f in the stationary supports 5 a, 5 b.
[0035] Referring back to FIGS. 1 and 3 , the stationary support 5 a is fixedly attached to a stationary support sleeve 42 , which coaxially encloses the hollow shaft 10 and extends through the wall of the hub shell 40 . The end of the stationary support sleeve 42 that extends through the hub shell 40 attaches to the frame support and preferentially has a non-cylindrical shape to enhance subsequent attachment of a torque lever 43 . As shown more clearly in FIG. 7 , the torque lever 43 is placed over the non-cylindrical shaped end of the stationary support sleeve 42 , and is held in place by a torque nut 44 . The torque lever 43 at its other end is rigidly attached to a strong, non-moving part, such as a frame (not shown). A stationary support bearing 48 supports the hub shell 40 and permits the hub shell 40 to rotate relative to the stationary support sleeve 42 .
[0036] Referring back to FIGS. 1 and 2 , shifting is manually activated by axially sliding a rod 11 positioned in the hollow shaft 10 . One or more pins 12 are inserted through one or more transverse holes in the rod 11 and further extend through one or more longitudinal slots 16 (not shown) in the hollow shaft 10 . The slots 16 in the hollow shaft 10 allow for axial movement of the pin 12 and rod 11 assembly in the hollow shaft 10 . As the rod 11 slides axially in the hollow shaft 10 , the ends of the transverse pins 12 extend into and couple with a coaxial sleeve 19 . The sleeve 19 is fixedly attached at each end to a substantially planar platform 13 a, 13 b forming a trough around the circumference of the sleeve 19 .
[0037] As seen more clearly in FIG. 4 , the planar platforms 13 a, 13 b each contact and push multiple wheels 21 a - f. The wheels 21 a - f fit into slots in the spindle supports 2 a - f and are held in place by wheel axles 22 a - f. The wheel axles 22 a - f are supported at their ends by the spindle supports 2 a - f and allow rotational movement of the wheels 21 a - f.
[0038] Referring back to FIGS. 1 and 2 , the substantially planar platforms 13 a, 13 b transition into a convex surface at their outer perimeter (farthest from the hollow shaft 10 ). This region allows slack to be taken up when the spindle supports 2 a - f and power adjusters 1 a, 1 b, 1 c are tilted as the transmission 100 is shifted. A cylindrical support member 18 is located in the trough formed between the planar platforms 13 a, 13 b and sleeve 19 and thus moves in concert with the planar platforms 13 a, 13 b and sleeve 19 . The support member 18 rides on contact bearings 17 a, 17 b located at the intersection of the planar platforms 13 a, 13 b and sleeve 19 to allow the support member 18 to freely rotate about the axis of the transmission 100 . Thus, the bearings 17 a, 17 b, support member 18 , and sleeve 19 all slide axially with the planar platforms 13 a, 13 b when the transmission 100 is shifted.
[0039] Now referring to FIGS. 3 and 4 , stationary support rollers 30 a - l are attached in pairs to each spindle leg 2 a - f through a roller pin 31 a - f and held in place by roller clips 32 a - l. The roller pins 31 a - f allow the stationary support rollers 30 a - l to rotate freely about the roller pins 31 a - f. The stationary support rollers 30 a - l roll on a concave radius in the stationary support 5 a, 5 b along a substantially parallel path with the grooves 6 a - f. As the spindle rollers 4 a - f move back and forth inside the grooves 6 a - f, the stationary support rollers 30 a - l do not allow the ends of the spindles 3 a, 3 b, 3 c nor the spindle rollers 4 a - f to contact the bottom surface of the grooves 6 a - f, to maintain the position of the spindles 3 a, 3 b, 3 c, and to minimize any frictional losses.
[0040] FIG. 4 shows the stationary support rollers 30 a - l, the roller pins, 31 a - f, and roller clips 32 a - l, as seen through the stationary support 5 a, for ease of viewing. For clarity, i.e., too many numbers in FIG. 1 , the stationary support rollers 30 a - l, the roller pins, 31 a - f, and roller clips 32 a - l, are not numbered in FIG. 1 .
[0041] Referring to FIGS. 1 and 5 , a concave drive disc 34 , located adjacent to the stationary support 5 b, partially encapsulates but does not contact the stationary support 5 b. The drive disc 34 is rigidly attached through its center to a screw 35 . The screw 35 is coaxial to and forms a sleeve around the hollow shaft 10 adjacent to the stationary support 5 b and faces a driving member 69 . The drive disc 34 is rotatively coupled to the power adjusters 1 a, 1 b, 1 c along a circumferential bearing surface on the lip of the drive disc 34 . A nut 37 is threaded over the screw 35 and is rigidly attached around its circumference to a bearing disc 60 . One face of the nut 37 is further attached to the driving member 69 . Also rigidly attached to the bearing disc 60 surface are a plurality of ramps 61 which face the drive disc 34 . For each ramp 61 there is one ramp bearing 62 held in position by a bearing cage 63 . The ramp bearings 62 contact both the ramps 61 and the drive disc 34 . A spring 65 is attached at one end to the bearing cage 63 and at its other end to the drive disc 34 , or the bearing disc 60 in an alternate embodiment, to bias the ramp bearings 62 up the ramps 61 . The bearing disc 60 , on the side opposite the ramps 61 and at approximately the same circumference contacts a hub cap bearing 66 . The hub cap bearing 66 contacts both the hub cap 67 and the bearing disc 60 to allow their relative motion. The hub cap 67 is threaded or pressed into the hub shell 40 and secured with an internal ring 68 . A sprocket or pulley 38 is rigidly attached to the rotating driving member 69 and is held in place externally by a cone bearing 70 secured by a cone nut 71 and internally by a driver bearing 72 which contacts both the driving member 69 and the hub cap 67 .
[0042] In operation, an input rotation from the sprocket or pulley 38 , which is fixedly attached to the driver 69 , rotates the bearing disc 60 and the plurality of ramps 61 causing the ramp bearings 62 to roll up the ramps 61 and press the drive disc 34 against the power adjusters 1 a, 1 b, 1 c. Simultaneously, the nut 37 , which has a smaller lead than the ramps 61 , rotates to cause the screw 35 and nut 37 to bind. This feature imparts rotation of the drive disc 34 against the power adjusters 1 a, 1 b, 1 c. The power adjusters 1 a, 1 b, 1 c when rotating, contact and rotate the hub shell 40 .
[0043] When the transmission 100 is coasting, the sprocket or pulley 38 stops rotating but the hub shell 40 and the power adjusters 1 a, 1 b, 1 c continue to rotate. This causes the drive disc 34 to rotate so that the screw 35 winds into the nut 37 until the drive disc 34 no longer contacts the power adjusters 1 a, 1 b, 1 c.
[0044] Referring to FIGS. 1, 6 , and 7 , a coiled spring 80 , coaxial with the transmission 100 , is located between and attached by pins or other fasteners (not shown) to both the bearing disc 60 and drive disc 34 at the ends of the coiled spring 80 . During operation of the transmission 100 , the coiled spring 80 ensures contact between the power adjusters 1 a, 1 b, 1 c and the drive disc 34 . A pawl carrier 83 fits in the coiled spring 80 with its middle coil attached to the pawl carrier 83 by a pin or standard fastener (not shown). Because the pawl carrier 83 is attached to the middle coil of the coiled spring 80 , it rotates at half the speed of the drive disc 34 when the bearing disc 60 is not rotating. This allows one or more lock pawls 81 a, 81 b, 81 c, which are attached to the pawl carrier 83 by one or more pins 84 a, 84 b, 84 c, to engage a drive disc ratchet 82 , which is coaxial with and rigidly attached to the drive disc 34 . The one or more lock pawls 84 a, 84 b, 84 c are preferably spaced asymmetrically around the drive disc ratchet 82 . Once engaged, the loaded coiled spring 80 is prevented from forcing the drive disc 34 against the power adjusters 1 a , 1 b , 1 c . Thus, with the drive disc 34 not making contact against the power adjusters 1 a , 1 b , 1 c the transmission 100 is in neutral and the ease of shifting is increased. The transmission 100 can also be shifted while in operation.
[0045] When operation of the transmission 100 is resumed by turning the sprocket or pulley 38 , one or more release pawls 85 a, 85 b, 85 c, each attached to one of the lock pawls 81 a, 81 b, 81 c by a pawl pin 88 a, 88 b, 88 c, make contact with an opposing bearing disc ratchet 87 . The bearing disc ratchet 87 is coaxial with and rigidly attached to the bearing disc 60 . The bearing disc ratchet 87 actuates the release pawls 85 a, 85 b, 85 c because the release pawls 85 a, 85 b, 85 c are connected to the pawl carrier 83 via the lock pawls 81 a, 81 b, 81 c. In operation, the release pawls 85 a, 85 b, 85 c rotate at half the speed of the bearing disc 60 , since the drive disc 34 is not rotating, and disengage the lock pawls 81 a, 81 b, 81 c from the drive disc ratchet 82 allowing the coiled spring 80 to wind the drive disc 34 against the power adjusters 1 a, 1 b, 1 c. One or more pawl tensioners (not shown), one for each release pawl 85 a, 85 b, 85 c, ensures that the lock pawls 81 a, 81 b, 81 c are pressed against the drive disc ratchet 82 and that the release pawls 85 a, 85 b, 85 c are pressed against the bearing disc ratchet 87 . The pawl tensioners are attached at one end to the pawl carrier 83 and make contact at the other end to the release pawls 85 a, 85 b, 85 c. An assembly hole 93 (not shown) through the hub cap 67 , the bearing disc 60 , and the drive disc 34 , allows an assembly pin (not shown) to be inserted into the loaded coiled spring 80 during assembly of the transmission 100 . The assembly pin prevents the coiled spring 80 from losing its tension and is removed after transmission 100 assembly is complete.
[0046] Referring to FIGS. 1, 11 , 12 , and 15 , automatic shifting of the transmission 100 , is accomplished by means of spindle cables 602 , 604 , 606 which are attached at one end to a non-moving component of the transmission 100 , such as the hollow shaft 10 or the stationary support 5 a. The spindle cables 602 , 604 , 606 then travel around spindle pulleys 630 , 632 , 634 , which are coaxially positioned over the spindles 3 a, 3 b, 3 c. The spindle cables 602 , 604 , 606 further travel around spacer pulleys 636 , 638 , 640 , 644 , 646 , 648 which are attached to a spacer extension 642 which may be rigidly attached to the spacers 8 a, 8 b, 8 c. As more clearly shown in FIGS. 11 and 12 , the other ends of the spindle cables 602 , 604 , 606 are attached to a plurality of holes 620 , 622 , 624 in a non-rotating annular bearing race 816 . A plurality of weight cables 532 , 534 , 536 are attached at one end to a plurality of holes 610 , 612 , 614 in a rotating annular bearing race 806 . An annular bearing 808 , positioned between the rotating annular bearing race 806 and the non-rotating annular bearing race 816 , allows their relative movement.
[0047] Referring to FIG. 15 , the transmission 100 is shown with the cable routing for automatic shifting.
[0048] As shown in FIGS. 1, 9 , 11 , and 12 , the weight cables 532 , 534 , 536 then travel around the hub shell pulleys 654 , 656 , 658 , through holes in the hub shell 40 , and into hollow spokes 504 , 506 , 508 (best seen in FIG. 12 ) where they attach to weights 526 , 528 , 530 . The weights 526 , 528 , 530 are attached to and receive support from weight assisters 516 , 518 , 520 which attach to a wheel 514 or other rotating object at there opposite end. As the wheel 514 increases its speed of rotation, the weights 526 , 528 , 530 are pulled radially away from the hub shell 40 , pulling the rotating annular bearing race 806 and the non-rotating annular bearing race 816 axially toward the hub cap 67 . The non-rotating annular bearing race 816 pulls the spindle cables 602 , 604 , 606 , which pulls the spindle pulleys 630 , 632 , 634 closer to the hollow shaft 10 and results in the shifting of the transmission 100 into a higher gear. When rotation of the wheel 514 slows, one or more tension members 9 positioned inside the hollow shaft 10 and held in place by a shaft cap 92 , push the spindle pulleys 630 , 632 , 634 farther from the hollow shaft 10 and results in the shifting of the transmission 100 into a lower gear.
[0049] Alternatively, or in conjunction with the tension member 9 , multiple tension members (not shown) may be attached to the spindles 3 a, 3 b, 3 c opposite the spindle pulleys 630 , 632 , 634 .
[0050] Still referring to FIG. 1 , the transmission 100 can also be manually shifted to override the automatic shifting mechanism or to use in place of the automatic shifting mechanism. A rotatable shifter 50 has internal threads that thread onto external threads of a shifter screw 52 which is attached over the hollow shaft 10 . The shifter 50 has a cap 53 with a hole that fits over the rod 11 that is inserted into the hollow shaft 10 . The rod 11 is threaded where it protrudes from the hollow shaft 10 so that nuts 54 , 55 may be threaded onto the rod 11 . The nuts 54 , 55 are positioned on both sides of the cap 53 . A shifter lever 56 is rigidly attached to the shifter 50 and provides a moment arm for the rod 11 . The shifter cable 51 is attached to the shifter lever 56 through lever slots 57 a, 57 b, 57 c. The multiple lever slots 57 a, 57 b, 57 c provide for variations in speed and ease of shifting.
[0051] Now referring to FIGS. 1 and 10 , the shifter cable 51 is routed to and coaxially wraps around a handlegrip 300 . When the handlegrip 300 is rotated in a first direction, the shifter 50 winds or unwinds axially over the hollow shaft 10 and pushes or pulls the rod 11 into or out of the hollow shaft 10 . When the handlegrip 300 is rotated in a second direction, a shifter spring 58 , coaxially positioned over the shifter 50 , returns the shifter 50 to its original position. The ends of the shifter spring 58 are attached to the shifter 50 and to a non-moving component, such as a frame (not shown).
[0052] As seen more clearly in FIG. 10 , the handlegrip 300 is positioned over a handlebar (not shown) or other rigid component. The handlegrip 300 includes a rotating grip 302 , which consists of a cable attachment 304 that provides for attachment of the shifter cable 51 and a groove 306 that allows the shifter cable 51 to wrap around the rotating grip 302 . A flange 308 is also provided to preclude a user from interfering with the routing of the shifter cable 51 . Grip ratchet teeth 310 are located on the rotating grip 302 at its interface with a rotating clamp 314 . The grip ratchet teeth 310 lock onto an opposing set of clamp ratchet teeth 312 when the rotating grip 302 is rotated in a first direction. The clamp ratchet teeth 312 form a ring and are attached to the rotating clamp 314 which rotates with the rotating grip 302 when the grip ratchet teeth 310 and the clamp ratchet teeth 312 are locked. The force required to rotate the rotating clamp 314 can be adjusted with a set screw 316 or other fastener. When the rotating grip 302 , is rotated in a second direction, the grip ratchet teeth 310 , and the clamp ratchet teeth 312 disengage. Referring back to FIG. 1 , the tension of the shifter spring 58 increases when the rotating grip 302 is rotated in the second direction. A non-rotating clamp 318 and a non-rotating grip 320 prevent excessive axial movement of the handlegrip 300 assembly.
[0053] Referring to FIGS. 13 and 14 , another embodiment of the transmission 900 , is disclosed. For purposes of simplicity, only the differences between the transmission 100 and the transmission 900 are discussed.
[0054] Replacing the rotating hub shell 40 are a stationary case 901 and housing 902 , which are joined with one or more set screws 903 , 904 , 905 . The set screws 903 , 904 , 905 may be removed to allow access for repairs to the transmission 900 . Both the case 901 and housing 902 have coplanar flanges 906 , 907 with a plurality of bolt holes 908 , 910 , 912 , 914 for insertion of a plurality of bolts 918 , 920 , 922 , 924 to fixedly mount the transmission 900 to a non-moving component, such as a frame (not shown).
[0055] The spacer extension 930 is compressed between the stationary case 901 and housing 902 with the set screws 903 , 904 , 905 and extend towards and are rigidly attached to the spacers 8 a, 8 b, 8 c. The spacer extension 930 prevents rotation of the stationary supports 5 a, 5 b. The stationary support 5 a does not have the stationary support sleeve 42 as in the transmission 100 . The stationary supports 5 a, 5 b hold the hollow shaft 10 in a fixed position. The hollow shaft 10 terminates at one end at the stationary support 5 a and at its other end at the screw 35 . An output drive disc 942 is added and is supported against the case 901 by a case bearing 944 . The output drive disc 942 is attached to an output drive component, such as a drive shaft, gear, sprocket, or pulley (not shown). Similarly, the driving member 69 is attached to the input drive component, such as a motor, gear, sprocket, or pulley.
[0056] Referring to FIG. 16 , shifting of the transmission 900 is accomplished with a single cable 946 that wraps around each of the spindle pulleys 630 , 632 , 634 . At one end, the single cable 946 is attached to a non-moving component of the transmission 900 , such as the hollow shaft 10 or the stationary support 5 a. After traveling around each of the spindle pulleys 630 , 632 , 634 and the spacer pulleys 636 , 644 , the single cable 946 exits the transmission 900 through a hole in the housing 902 . Alternatively a rod (not shown) attached to one or more of the spindles 3 a, 3 b, 3 c, may be used to shift the transmission 900 in place of the single cable 946 .
[0057] The foregoing description details certain embodiments of the invention. It will be appreciated, however, that no matter how detailed the foregoing appears in text, the invention can be practiced in many ways. As is also stated above, it should be noted that the use of particular terminology when describing certain features or aspects of the invention should not be taken to imply that the terminology is being re-defined herein to be restricted to including any specific characteristics of the features or aspects of the invention with which that terminology is associated. The scope of the invention should therefore be construed in accordance with the appended claims and any equivalents thereof. | A continuously variable transmission is disclosed for use in rotationally or linearly powered machines and vehicles. The single axle transmission provides a simple manual shifting method for the user. An additional embodiment is disclosed which shifts automatically dependent upon the rotational speed of the wheel. Further, the practical commercialization of traction roller transmissions requires improvements in the reliability, ease of shifting, function and simplicity of the transmission. The disclosed transmission may be used in vehicles such as automobiles, motorcycles, and bicycles. The transmission may, for example, be driven by a power transfer mechanism such as a sprocket, gear, pulley or lever, optionally driving a one way clutch attached at one end of the main shaft. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a jig apparatus for use in extending a belt across (or assembling a belt onto) a pair of pulleys in a variator (or a continuously variable transmission).
2. Description of the Related Art
As a transmission for a motor vehicle, there has been recently used a variator which is provided with a pair of pulleys each having a V-shaped groove (also called a "V-groove") whose groove width is variable, and a belt to link or drive them together. In this variator, by increasing or decreasing the groove widths of the pulleys in a manner, or in a direction, opposite to each other, the transmission ratio (or speed-changing ratio) is continuously varied. The pulley to be used in this variator is made up by mounting a fixed (or stationary) sheave half member (or simply called a "sheave half") and a movable sheave half on a single rotary shaft, and the movable sheave half is held in a manner to be movable in the axial direction of the rotary shaft by means of hydraulic pressure, or the like. By varying the distance between the two sheave halves, the size of the pitch diameter of the belt to be extended across the pulleys is varied, whereby the speed changing ratio can be variably, or steplessly, changed. Also, the rotary shafts of both of the pulleys is supported on both of ends inside the transmission. It follows that the belt must be extended across both the pulleys before the pulleys are assembled into the transmission. However, the movable sheave half is urged, or pressed, in the direction of narrowing the groove width by means of a spring so as not to loosen the belt even if the hydraulic pressure for moving the movable sheave half is lowered. Accordingly, in a condition before assembling both the pulleys into the transmission, they are both in a state of maximum pitch diameter. The belt will thus be too short to be extended across both the pulleys. It therefore becomes necessary, in assembly steps of each pulley, to place the belt on one of the sheave halves and then assemble the other sheave half to thereby pinch the belt between both the sheave halves.
If it is attempted to assemble the belt simultaneously with the assembling of the pulleys, the pair of pulleys must be assembled at the same time. This results in a disadvantage in that the assembly steps of the pulleys become complicated and that, should a mistake happen in the assembling of one of the pulleys, the other pulley cannot be used anymore.
SUMMARY OF THE INVENTION
In view of the above disadvantages, the present invention has an object of providing such a jig apparatus for assembling a belt of a variator as will enable one to extend the belt across both the pulleys in a condition in which the pair of pulleys have been previously assembled.
In order to attain the above object, the present invention is a jig apparatus for use in extending a belt across a pair of pulleys of a variator, the jig apparatus comprising: a pair of holding members for holding the pulleys such that an axial line of rotation of each of the pulleys becomes parallel to each other; widening means for widening a groove width of at least one of the pulleys; and moving means for relatively moving the both holding members such that a sheave half of each of the pulleys gets into a pulley groove of the other of the pulleys.
Preferably, the widening means is made up of a means for inputting a negative pressure or a positive pressure to a hydraulic actuator which controls an axial movement of a movable sheave half of at least one of the pulleys, or the widening means is made up of a mechanical axial moving means operative to engage a movable sheave half of at least one of the pulleys and to thereby move it with respect to the fixed sheave half.
The belt is set to such a length as to be effectively engaged with, or extended across, both the pulleys when, in a condition in which both the pulleys have been assembled into the variator, the groove width of one of the pulleys is maximum and the groove width of the other is minimum. Therefore, if the pitch diameter is made smaller by enlarging the groove width of at least one of the pulleys, and if the distance between the axes of both the pulleys is narrowed by moving the holding means such that the sheave half of each of the pulleys gets into, or is brought into, the pulley groove of the other of the pulleys, the belt that is set to the above-described length can be assembled or fit onto both the pulleys.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and the attendant advantages of the present invention will become readily apparent by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:
FIG. 1 is a front view, partly shown in section, showing the construction of one embodiment of the apparatus of the present invention;
FIG. 2 is a plan view showing the construction of the embodiment shown in FIG. 1;
FIG. 3 is a front view showing the operation performed by lifting the handle;
FIG. 4 is a sectional view taken along the line IV--IV in FIG. 1;
FIG. 5 is a front sectional view showing another embodiment in which the V-groove is widened; and
FIG. 6 is a front sectional view showing still another embodiment in which the V-groove is widened by pressurizing.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to the drawings, references DR and DN denote pulleys to be assembled onto a variator (or a continuously variable transmission), and DR denotes a drive pulley on an input side and DN denotes a driven pulley on an output side. Both the pulleys DR, DN have the same construction. An explanation about the construction will now be made by taking the drive pulley DR as an example. On a rotary shaft S there is integrally formed a fixed or stationary sheave half B1 which constitutes one of the inclined surfaces of the V-shaped groove or the V-groove. A movable sheave half B2 which constitutes the other of the inclined surfaces of the V-groove is mounted on the rotary shaft S via a ball spline in a manner movable in the axial direction of the rotary shaft S. On the rear surface of the movable sheave half B2 there is fixed a cylinder CL of a cylindrical shape. On the inner side of the cylinder CL, a piston P which forms an oil chamber in cooperation with the rear surface of the movable sheave B2 is fixedly assembled to the rotary shaft S. The cylinder CL and the piston P constitute a hydraulic actuator which controls an axial movement of the movable sheave half B2. When a working oil is introduced from an oil pressure supply passage L in the rotary shaft S to the oil chamber via oil passages L1, L2, the movable sheave half B2 is moved towards the stationary sheave B1, thereby narrowing the width of the V-groove. In the oil chamber there is disposed a spring, in a contracted condition, which urges the movable sheave B2 towards the stationary sheave half B1. A supporting bar 22 which projects upwards from an upper surface of the jig apparatus 1 for assembling a belt is inserted into the oil pressure supply passage L which is provided in the rotary shaft S of the drive pulley DR. The drive pulley DR is thus vertically erected such that the side of the movable sheave half B2 is located downwards. On the other hand, the rotary shaft of the driven pulley DN is inserted into a supporting pipe 32 which projects upwards from the upper surface of a jig apparatus 1 such that the side of the movable sheave half is located upwards. The belt SB is disposed in advance on the upper surface of the jig apparatus 1 so that it encircles the supporting bar 22 and the supporting pipe 32.
This supporting bar 22 is mounted on an upper surface of an elevating base 2 which is supported by a linear guide 21 so as to be movable up and down, and is also provided with an axial hole 23 which is communicated with a vacuum pump (not illustrated). When the drive pulley DR is set in position onto the supporting bar 22, the axial hole 23 is communicated with the oil passage L1 via a radial communicating hole 23a. On the other hand, the supporting pipe 32 is mounted on a shift base 3 which is supported by a linear guide 31 mounted at a predetermined angle to the horizontal surface. This shift base 3 is arranged to move parallel with a plane including the supporting bar 22 and the supporting pipe 32, and to rise by a predetermined angle with a movement to approach the supporting bar 22.
On the bottom surface of the jig apparatus 1, there is laterally provided a swing shaft 4 in a position between the supporting bar 22 and the supporting pipe 32. To the swing shaft 4 there are attached an arm 42 which extends towards the supporting bar 22 and a handle 41 which extends towards the supporting pipe 32. On the front end of the arm 42 there is mounted a roller 43 in a manner to be engaged with a C-shaped (or channel-shaped) member 44 which is attached to the elevating base 2. In an intermediate portion of the handle 41 there is mounted a roller 45 in a manner to be engaged with a cam plate 46 which is attached to the shift base 3. The operation of this handle 41 will now be explained with reference to FIG. 3. When the handle 41 is in an initial condition as shown in FIG. 1, the roller 43 contacts an upper edge 44a of the C-shaped member 44 to thereby hold the elevating base 2 in an upper end position. The roller 45, on the other hand, is in a condition of being out of contact with the groove of the cam plate 46. When the handle 41 is then lifted, the elevating base 2 lowers to the lower end position accompanied by the lowering of the roller 43 while keeping contact with the upper edge 44a. The roller 45 will be in a condition in which it contacts an inclined surface 46a of the cam plate 46. When the handle 41 is further lifted, the elevating base 2 will not lower any more because it is already held in its lower end position by a stopper (not illustrated), whereby the roller 43 leaves the upper edge 44a. The roller 45, on the other hand, moves relatively along the inclined surface 46a to move the shift base 3 along the linear guide 31 via the cam plate 46, whereby a sheave half of each of the pulleys DR, DN enters, or is brought into, the groove of the other as shown in FIG. 3.
An explanation will now be made about the method of operating the jig apparatus 1.
First, in a condition as illustrated in FIG. 1, the belt SB, the drive pulley DR and the driven pulley DR are set in position as described above. Then, the above-described vacuum pump (not illustrated) is operated to thereby evacuate the oil pressure chamber of the drive pulley DR into a negative pressure. As a result, the movable sheave half B2 lowers against the urging force of the spring SP, whereby the groove width of the drive pulley DR is widened. Then, if the handle 41 is pulled up to an intermediate position, the drive pulley DR is lowered. If the handle 41 is further pulled up, the driven pulley DN will, at this time, approach the drive pulley DR while the driven pulley DN keeps on being raised, at a predetermined angle. A sheave half of the respective pulleys DR, DN is placed inside, or is brought into, the pulley groove of the other of the pulleys DR, DN, thereby reducing the distance between the axes of both the pulleys. In this condition, the belt SB is placed into the groove of each of the pulleys DR, DN and thereafter the handle 41 is returned to the initial condition. The operation of the vacuum pump is stopped and the assembling of the belt SB is completed.
In the above-described embodiment, the groove width of the drive pulley DR is widened. However, it is also possible to widen the groove width of the driven pulley DN, or else to widen the groove widths of both the pulleys.
Further, in the above-described embodiment, the movable sheave half B2 is lowered by making the oil pressure chamber into a negative pressure. However, it is also possible to lower the moveable sheave half B2 mechanically by the use of an engaging member which engages with the movable sheave half B2 and urges it downwardly.
Also, in the above-described embodiment, there are provided the axial hole 23 and the communicating hole 23a in the supporting bar 22. However, the following arrangement may also be employed as shown in FIG. 5. Namely, a solid supporting bar 22' is provided on the elevating base 2. The drive pulley DR is supported on the supporting bar 22', and a hollow plug 23' which is connected to a vacuum pump (not illustrated) is plugged into an upper opening of the oil pressure supply passage L to thereby widen the groove width of the V-groove.
Furthermore, it is also possible to widen the groove width of the V-groove by pressurizing or giving a positive pressure. Such an embodiment will now be explained by taking the driven pulley DN as an example with reference to FIG. 6. A cylinder plate PL of a cylindrical shape is fixed to a rear surface of the piston P, and a seal R is mounted on an open edge of the cylinder CL so as to be slidable along the surface of the cylinder plate PL, whereby a second oil chamber BR is provided. By pressurizing this oil chamber BR the groove width of the V-groove is widened. In this embodiment, a pressurizing bar 5 is inserted into the oil pressure supply passage L, and pressurized air from a supply source (not illustrated) is sent under pressure from an opening 52 to the oil pressure supply passage L via a pressurizing passage 51 which is provided inside the pressurizing bar 5. The oil chamber BR is thus subjected to a pressure via an oil passage L3. The air inside the oil chamber on the side of the spring SP is arranged to be discharged from the oil passages L1, L2 via an opening CR1 in a bush CR which is fitted onto the oil supply passage L.
As can be seen from the above explanations, according to the present invention, the belt can be fitted onto both the pulleys in a condition in which the pair of pulleys have been assembled. Therefore, the assembly steps of the pulleys are not complicated and, even if there occurs a mistake in assembling one of the pulleys, the other pulley will not be wasted.
It is readily apparent that the above-described jig apparatus for assembling a belt of a variator meets all of the objects mentioned above and also has the advantage of wide commercial utility. It should be understood that the specific form of the invention hereinabove described is intended to be representative only, as certain modifications within the scope of these teachings will be apparent to those skilled in the art.
Accordingly, reference should be made to the following claims in determining the full scope of the invention. | A jig apparatus is used in extending a belt across a pair of pulleys of a variator for a transmission of a motor vehicle. The variator has the pair of pulleys, a groove width of each of which is variable, and a belt for driving the pulleys. A supporting bar and a supporting pipe hold the pulleys such that an axial line of rotation of each of the pulleys becomes parallel to each other. A groove width of at least one of the pulleys is pneumatically or mechanically widened. A sheave half of each of the pulleys is brought into a pulley groove of the other of the pulleys. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to an inverter or switching circuit making use of complementary insulated gate field effect transistors (hereinafter abbreviated as CMOSFET's). More particularly, it relates to an inverter circuit with a capacitive load connected to the output terminal thereof in which a heavy transient current flows from a power supply under a transient condition where an input signal is changed to invert the inverter output.
Since an inverter circuit using CMOSFET's (hereinafter abbreviated as CMOS inverter) consumes little power in the steady state condition, its use in large-scale integrated circuits (thereinafter abbreviated as IC) is desirable. Under the transient condition, however, a considerably large power supply current (hereinafter abbreviated as I DD ) flows through the CMOS inverter due to a charging current flowing to a capacitive component of the load. Accordingly, the peak value of I DD in the CMOS inverter is large during the transient period. Therefore, it is necessary to take measures, such as lowering the impedance of power supply wirings to the CMOS inverter to reduce this transient current. But such a measure would deteriorate a valuable feature of the CMOS circuit; namely, that it can use fine wirings because of the low steady state power consumption. This problem becomes more remarkable in a memory IC where a large number of address inverters operate simultaneously. For instance, in a 64K-bit memory, an address input is 16-bits, which means that at least 16 address inverters operate simultaneously in response to 16 address input signals applied in parallel. In that case, I DD is multiplied by a factor of 16, causing an extremely large peak current to flow from the power supply of this memory IC. Consequently, a noise is generated in the power supply lines, causing many faults in the operation of the memory IC.
It has been proposed to reduce the peak current by prolonging the CMOS inverter switching time to thereby gradually charge the load capacitance. However, this method has a drawback that speed-up of the whole IC is prevented because of the prolonged response time of the inverter.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an inverter circuit, in which the peak value of the load capacitance charging current component of the power supply current can be largely reduced while maintaining high-speed operation.
According to one feature of the present invention, there is provided an inverter circuit responsive to an input signal for outputting an inverted signal of the input signal, with a first auxiliary circuit connected to the inverter circuit. The first auxiliary circuit includes an auxiliary capacitor which is charged at a time other than the transient time when the output transfers from the low level to the high level (e.g. when the input signal is "1" (or "0") level), and is discharged during the transient period when the input signal is changed from the low level to the high level. Since the discharge current from the auxiliary capacitor is added to the power supply current from the power supply for charging the capacitive load in the transient period, the peak power supply current during the transient period can be greatly reduced. The power supply current for charging the auxiliary capacitor flows at a time other than the transient period and contributes to the reduced peak current.
According to another feature of the invention, a second auxiliary circuit is added to the inverter circuit in parallel with the first auxiliary circuit to feed a part of the output current of the inverter circuit at least after the discharging current from the auxiliary capacitor starts to flow and favorably after the mentioned discharging current ends during the transient period.
The inverter circuit may comprise a first P-channel type field effect transistor (hereinafter abbreviated as Pch-FET) and a first N-channel type field effect transistor (hereinafter abbreviated as Nch-FET) connected in series between the two power supply terminals, the gates of these FET's being commonly connected to an input terminal, and the common junction point therebetween being used as an output terminal. The first auxiliary circuit may include second, third and fourth Pch-FET's (or Nch-FET's) connected in series between one of the power supply terminals and the output terminal of the inverter circuit with their respective gates connected to the other power supply terminal, the output terminal of the inverter circuit and the input terminal of the inverter circuit, respectively. An auxiliary capacitor is inserted between the common junction point between the second and third FET's and the other power supply terminal. The second auxiliary circuit may include a fifth Pch-FET (or Nch-FET) inserted between the one of the power supply terminals and the output terminal of the inverter circuit and a delay circuit coupled between the input terminal of the inverter circuit and the gate of the fifth FET. The second auxiliary circuit may further include a sixth Pch-FET (or Nch-FET) inserted between the drain of the fifth FET and the output terminal of the inverter circuit and having its gate connected to the input terminal of the inverter circuit. With the first and second auxiliary circuits, the inverter circuit according to this invention can reduce the peak value of the capacitive load charging current component of the power supply current as compared to the prior art inverter circuit, while maintaining a high-speed operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram of a basic inverter circuit in the prior art making use of CMOSFET's.
FIG. 2 illustrates the waveforms of an input signal φ IN , an output signal φ OUT , and a charging current component I DDL of the power supply current I DD as functions of time for the inverter circuit shown in FIG. 1,
FIG. 3 is a circuit diagram showing one preferred embodiment of the present invention,
FIG. 4 illustrates the waveforms of the input voltage φ IN the output voltage φ OUT and the charging current component I DDL of the power supply current as functions of time as the inverter circuit of FIG. 3 goes from the "1" level to "0" level.
FIG. 5 illustrates the waveforms of the input voltage φ IN , the output voltage φ OUT and the charging current components of the power supply current as functions of time as the inverter circuits of FIGS. 3 and 6 are changed from "0" level to "1" level.
FIG. 6 is a circuit diagram showing another preferred embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1, a prior art inverter circuit comprises an Nch-FET Q 1 and a Pch-FET Q 2 with their drains connected in common to form an output terminal 3. The source of the FET Q 1 is connected to a V SS power supply terminal (in the illustrated example, to the ground terminal) and the source of the FET Q 2 is connected to a V DD power supply terminal 4 (in the illustrated example, V DD represents a positive voltage). The gates of both FET's are connected in common and form an input terminal 2. It is to be noted that a load capacitor C L is present between the output terminal 3 and the ground terminal.
Referring also to FIG. 2, when the input signal φ IN is at "1" level (in the illustrated example, a high voltage V DD level) at a time t o , the Nch-FET Q 1 is ON, and hence the output signal φ OUT maintains "0" level (V SS level). Since the Pch-FET Q 2 is OFF at this time, the power supply current I DD does not flow. Subsequently, the input signal φ IN begins to transfer from the "1" level to the "0" level (in the illustrated example the low voltage V SS is the 0 volt level), and when the voltage of the input signal has lowered to V DD -|V TP | (V TP : a threshold voltage of the Pch-FET Q 2 ) at a time t 1 , the Pch-FET Q 2 is turned ON and a power supply current I DD begins to flow. As a result, the voltage of the output signal φ OUT begins to rise, determined by the capability ratio between the Nch-FET Q 1 and the Pch-FET Q 2 . As the voltage of the output signal φ OUT rises, the load capacitor C L is driven, and a charging current I DDL flows from the V DD power supply terminal through the Pch-FET Q 2 into the load capacitor C L . Therefore, the power supply current I DD which is the sum of the charging current I DDL and a current I DDO flowing through the FET Q 1 to the ground becomes large. Then, the input signal φ IN approaches the "0" level, and when the voltage reaches V TN (a threshold voltage of the Nch-FET Q 1 ), the Nch-FET Q 1 is turned OFF, and the power supply current component flowing through the Nch-FET Q 1 (I DDO ) stops. When the input signal φ IN reaches "0" level at a time t 2 , the output signal φ OUT also reaches "1" level, so that the I DDL also stops flowing. Thus the charging current component I DDL has a nearly symmetric waveform with a large peak value. The peak value of the charging current I DDL become larger as the load capacitor C L is increased. As described previously, an important problem to be solved is how best to reduce the peak value of this I DDL .
With reference to FIG. 3, the circuit of a preferred embodiment of the present invention comprises a basic inverter circuit 11 which includes a first Pch-FET Q 12 and a first Nch-FET Q 11 connected in series at an output terminal 17. The source of the Nch-FET Q 11 is connected to V SS terminal (the ground terminal in this example) and the source of the Pch-FET Q 12 is connected to a V DD power supply terminal 16. The gates of the Nch-FET Q 11 and the Pch-FET Q 12 are both connected to an input terminal 15. A first auxiliary circuit 12 is added to the inverter circuit 11, which in turn includes second, third and fourth Pch-FET's Q 14 , Q 15 and Q 16 connected in series between the V DD power supply terminal 16 and the output terminal 17. The respective gates of Q 14 , Q 15 and Q 16 are connected to the input terminal 15, the output terminal 17, and the ground terminal, respectively. The first auxiliary circuit further includes an auxiliary capacitor C A inserted between the common junction point N2 of the Pch-FET's Q 15 and Q 16 and the ground terminal. A second auxiliary circuit 13 is also added, which includes a fifth Pch-FET Q 13 inserted between the V DD power supply terminal 16 and the output terminal 17 and a delay circuit 14 inserted between the input terminal 15 and the gate of Q 13 . The delay circuit 14 is used to delay the input signal φ IN by a predetermined period. Since precision is not required, the delay circuit 14 can be easily constructed using known techniques.
Now description will be made of the operation of this circuit when the input signal φ IN transfers from "1" level (V DD ) to the "0" level (ground), with reference to FIG. 4. Since the basic inverter circuit 11 has the same construction as the circuit in the prior art shown in FIG. 1, its operation is basically the same as that of the prior art circuit.
At first, when the input signal φ IN is at the "1" level (V DD ) at a time between t o and t 11 , the Pch-FET's Q 15 and Q 16 of the first auxiliary circuit 12 are ON and the Pch-FET Q 14 is OFF. Hence the auxiliary capacitor C A is charged via the Pch-FET Q 16 by V DD and stores electric charge therein. Accordingly, the charging current I DDA for this capacitor C A flows from the V DD power supply terminal 16 as a component of the power supply current I DD , during the period of time t o to t 11 . At this moment, the Nch-FET Q 11 is ON and the Pch-FET's Q 12 and Q 13 are OFF. Therefore, the output voltage φ OUT at the output terminal 17 is at the "0" level, and the power supply current I DDO through the Nch-FET Q 11 and the charging current I DDL for the load capacitor C L are both zero.
Within the period of t 0 to t 11 , the input signal φ IN starts to fall. When the voltage of the input signal φ IN is lowered to V DD -|V TP | at the time t 11 , the Pch-FET Q 12 and the Pch-FET Q 14 are turned ON, and hence a current I DDO through the Pch-FET Q 12 and the Nch-FET Q 11 and a charging current I DDL1 through the Pch-FET Q 12 and load capacitor C L for charging the load capacitor C L begin to flow. Furthermore, the electric charge previously stored in the auxiliary capacitor C A begins to discharge as a part of the charging current for the load capacitor C L through the Pch-FET Q 14 (this component being represented by I DDL2 ). Since this discharge current I DDL2 is based on the discharge of electric charge that has been preliminarily stored in the auxiliary element C A , an increment of the power supply current I DD that is necessary for I.sub. DDL2 after the time t 11 is very small. If the conductance of the Pch-FET Q 16 is chosen less than about 1/10 of that of the Pch-FET Q 12 , then the I DD component passing through the Pch-FET Q 16 is very small, and therefore it can be neglected. Moreover, if the auxiliary capacitor C A is chosen nearly the same size as the load capacitor C L , then about one-half of the charging current I DDL can be obtained from I DDL2 .
Subsequently, the voltage of the input signal φ IN is further lowered after t 11 and accordingly the voltage of the output signal φ OUT rises, and when the output voltage value reaches about V DD /2 at a time t 12 , the input signal φ' IN delayed by the delay circuit 14 in the second auxiliary circuit is applied to the Pch-FET Q 13 , so that the Pch-FET Q 13 is turned ON and sends out an output current to the output terminal 17 which forms another part of the charging current for the load capacitor C L (this component being called I DDL3 ). As a result the power supply current I DD now includes the I DDL3 component. On the other hand, the potential at the node N 2 which serves as one terminal of the auxiliary capacitor C A becomes nearly the same level as the φ OUT when the voltage of the output signal φ out exceeds V DD /2, and hence the Pch-FET Q 15 is turned OFF, so that the charging current I DDL2 from the auxiliary capacitor C A is eliminated. Therefore, at this time the charging current for the load capacitor C L is comprised of two components; that is, the I DDL1 passing through the Pch-FET Q 12 and the I DDL3 passing through the Pch-FET Q 13 . This I DDL3 component compensates for the loss of the above-described I DDL2 component to promote charging of the load capacitor C L and serves to quickly raise the voltage of the output signal φ OUT . Therefore, it is favorable to select the conductance of the Pch-FET Q 13 larger than that of the Pch-FET Q 12 .
Next, when the input signal φ IN approaches the "0" level and its voltage becomes equal to or lower than V TN , then the Nch-FET Q 11 is turned OFF, and hence the I DDO component passing through the Nch-FET stops. Then, the input signal φ IN reaches the "0" level and the output signal φ OUT reaches the "1" level at a time t 13 , and as a result, the I DDL1 component passing through the Pch-FET Q 12 as well as the I DDL3 component passing through the Pch-FET Q 13 are also eliminated.
As will be apparent from the above description, in the circuit of the illustrated embodiment, the charging current I DDL for the load capacitor C L is formed in such a manner that until the voltage of the output signal φ OUT becomes nearly equal to V DD /2, the charging current is comprised of the I DDL1 passing through the Pch-FET Q 12 and the discharging current I DDL2 of the auxiliary capacitor C A which has been preliminarily charged, and after the output signal φ OUT nearly exceeds V DD /2, the I DDL2 is eliminated and instead the I DD3 passing through the Pch-FET Q 13 is newly added. Consequently, the load capacitor charging current component I DDL of the power supply current of the circuit would flow over the entire region of operation, and its peak value during the period t 11 to t 13 becomes very small as shown in FIG. 4. The extent of this reduction of the peak value depends upon the design of the first and second auxiliary circuits such as the magnitude of the auxiliary capacitor C A and the conductance of the Pch-FET Q 13 . However, it is quite easy to reduce the peak value of the charging current to 1/2 or less of the peak value in the prior art inverter circuit.
Furthermore, since those auxiliary charging currents can be subjected to appropriate adjustment by varying the delay characteristics of the delay circuit 14 in the second auxiliary circuit 13 so as to meet the response time of the circuit, there is no need to prolong a response time of the inverter circuit 11, and the response time may be rather shortened by selecting appropriate timing.
Now description will be made of the case where the input signal transfers from the "0" level to the "1" level, with reference to FIG. 5 which shows waveforms of the input signal φ IN , the output signal φ OUT and the power supply current I DD for this case.
At first, during the period t 0 to t 20 , when the input signal φ IN is at the "0" level (ground), the Pch-FET's Q 12 , Q 13 , Q 14 and Q 16 are ON and the Nch-FET Q 11 and the Pch-FET Q 15 are OFF. Accordingly, the auxiliary capacitor C A is charged, and a power supply charging current I DDA flows.
Next, the input signal φ IN starts to rise at a time t 20 . When it rises up to V TN at a time t 21 , the Nch-FET Q 11 is turned ON and the discharging current of the load capacitor C L begins to flow through the Nch-FET Q 11 . Furthermore the power supply current I DDO flows through the Pch-FET Q 12 and the Nch-FET Q 11 , and the power supply current I DDO ' flows through the Pch-FET Q 13 and the Nch-FET Q 11 . At this moment, since the Pch-FET Q 15 is kept OFF, only the I DDA flows through the first auxiliary circuit.
Subsequently, when the input signal φ IN reaches V DD -|V TP |, at a time t 23 , the Pch-FET Q 13 is turned OFF and the I DDO stops flowing, but since the voltage of the delayed signal φ IN for the input signal φ IN which is a driving voltage for the Pch-FET Q 13 does not rise as shown in FIG. 5, the Pch-FET Q 13 is still kept ON, and so the I DDO ' continues to flow. Thereafter when the φ' IN becomes V DD -V TP at a time t 24 , the Pch-FET Q 13 is turned OFF and the I DDO ' stops flowing. The input signal φ IN reaches the "1" level, and the output signal φ OUT reaches the "0" level.
In other words, in the transient period when the input signal φ IN transfers from the "0" level to the "1" level, the I DDO ' passing through the Pch-FET Q 13 is added to the power supply current I DDO which flows together with the discharge current of the load capacitor C L in the circuit known in the prior art, and therefore, the overall power supply current I' DD takes the form shown in FIG. 5. As described, the circuit of the illustrated embodiment of FIG. 3 has a problem that although the peak value of the load capacitor charging current component I DDL of the power supply current I DD can be greatly reduced when the input signal φ IN transfers from the "1" level to the "0" level, the power supply current I DDO ' caused by the second auxiliary circuit is added to the power supply current when the input signal φ IN transfers from the "0" level to the "1" level.
The circuit of another preferred embodiment of the present invention shown in FIG. 6 solves the above-mentioned problem. The only difference from the circuit shown in FIG. 3 and described previously resides in that the second auxiliary circuit 13' includes another Pch-FET Q 17 inserted between the drain of the Pch-FET Q 13 and the output terminal 17 and having its gate connected to the input terminal 15. In this circuit of the modified embodiment, the Pch-FET Q 17 is turned OFF in response to the input signal φ IN and the I DDO ' also ceases to flow at the same time when I DDO ceases to flow through Q 12 . Therefore, the I DD in this modified embodiment becomes small as indicated by I" DD in FIG. 5.
It is to be noted that in the above-described embodiments, the conductivity type of the respective FET's can be changed if necessary. For instance, in place of the Pch-FET an Nch-FET can be used for the FET Q 14 , and an inverted input signal φ IN would then be applied to the gate of this FET. The Pch-FET's and Nch-FET's may be replaced by Nch-FET's and Pch-FET's, respectively, with the terminals of the power supply voltage being reversely connected. | A buffer circuit, which supplies current to a capacitive load, has a first circuit for reducing the power supply charging current to the capacitive load during switching intervals. The first circuit includes a charge storage device precharged between inverter switching intervals to produce at least a portion of the load charging current during the switching intervals. A second circuit includes a switching element connected between the power supply and the capacitive load to electrically connect the power supply through the second circuit to the load at a selected time in the switching interval to supplement the charging current produced by the charge storage device. | 6 |
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