Patent application title: Power Transfer
Inventors:
Duncan James Parfitt (Powys, GB)
IPC8 Class: AF01K2700FI
USPC Class:
60523
Class name: Motor operated by expansion and/or contraction of a unit of mass of motivating medium unit of mass is a gas which is heated or cooled in one of a plurality of constantly communicating expansible chambers and freely transferable therebetween having electrical heating means for mass
Publication date: 2008-12-18
Patent application number: 20080307785
s to utilise the properties of expansion and
contraction of a fluid and in particular accelerated condensation of a
vapour and provides useable energy based on these properties in the form
of mechanical motion which can then be used to create an electrical
output. There is provided a system for driving a turbine, the system
comprising a conduit (5) and a chamber (2, 4), the conduit (6) defining a
fluid flow path within which said turbine is located. The conduit (6) is
in communication with an inlet to said chamber (2, 4). The system further
comprises a piston (10) mounted in said chamber (2, 4) so as to define an
enclosure (18) within said chamber and a heater for heating fluid within
the enclosure. There is also provided means to move said piston (10) in a
first direction (16) within said chamber (2, 4) causing expansion of said
enclosure (18), and heating means (8) for heating fluid within said
enclosure (18) so as to cause expansion of said fluid into said enclosure
(18). A condensing means (12) is also provided for condensing the fluid
so as to cause contraction thereof and corresponding movement of said
piston (10) in a second, opposite direction within said chamber (2, 4),
thereby creating a suction force at said inlet of said chamber (2, 4) and
drawing fluid through said conduit (6) and across said turbine.Claims:
1. A system for driving a turbine, the system comprising a conduit and a
chamber, the conduit defining a fluid flow path within which said turbine
is located, said conduit being in communication with an inlet to said
chamber, the system further comprising a piston mounted in said chamber
so as to define an enclosure within said chamber and means to move said
piston in a first direction within said chamber causing expansion of said
enclosure, and heating means for heating fluid within said enclosure so
as to cause expansion of said fluid into said enclosure, and condensing
means for condensing said fluid so as to cause contraction of said
enclosure and corresponding movement of said piston in a second, opposite
direction within said chamber, thereby creating a suction force at said
inlet of said chamber and drawing fluid through said conduit and across
said turbine.
2. A system according to claim 1 further comprising a control means arranged to switch said heating means off at a predetermined time.
3. A system according to claim 2, wherein said control means is arranged to determine a preselected movement of the piston in a first direction such that once said piston has moved a preselected distance a signal is transmitted to turn said heating means off.
4. A system according to claim 3, wherein the means to determine a preselected distance moved by said piston comprises a laser beam.
5. A system according to claim 1, wherein the heating means comprises an electric heating element.
6. A system according to claim 1, wherein said condensing means is mounted in said enclosure.
7. A system according to claim 1, wherein said condensing means is independently moveable of the piston.
8. A system according to any of claims 1, wherein said condensing means is releasably attached to the piston when the piston is moving in said first direction.
9. A system according to claim 8 further comprising means to release the condenser from said piston.
10. A system according to claim 1 further comprising means to force the condensing means through the enclosure.
11. A system according to claim 1 wherein said means to move said piston in a first direction preferably comprises a second chamber having an inlet in fluidic connection with said conduit, the system further comprising a second piston mounted in said second chamber so as to define a second enclosure within said second chamber, heating means for heating fluid to expand said fluid into said second enclosure, and a second condensing means for condensing said fluid so as to cause contraction of said second enclosure and corresponding movement of said piston in a direction to decrease the volume of said second enclosure, thereby creating a suction force at said inlet of said chamber and drawing fluid through said conduit and across said turbine and thereby causing corresponding movement of said piston within said chamber in said first direction.
12. A system according to claim 11 further comprising means to provide said fluid flow to reach the turbine in one direction, irrespective of the direction of travel of the fluid flow through said conduit.
13. A system according to claim 2, wherein the control means is arranged and configured to switch on the heating means in one chamber and switch off the heating means in the opposite chamber substantially simultaneously.
14. A method of driving a turbine comprising the steps of providing a conduit and a chamber, the conduit defining a fluid flow path within which said turbine is located, said conduit being in communication with an inlet to said chamber, further providing a piston mounted in said chamber so as to define an enclosure within said chamber, further providing means to move said piston in a first direction within said chamber so as to enlarge said enclosure, heating the fluid within said enclosure so as to cause expansion of said fluid to fill said enclosure, and condensing said fluid by a condensing means passing through said enclosure so as to cause contraction of said fluid and corresponding movement of said piston in a second, opposite direction within said chamber, thereby creating a suction force at said inlet of said chamber and drawing fluid through said conduit and across said turbine.
15. (canceled)Description:
[0001]The present invention relates to the an engine utilising the power
of vacuum's thermal expansion and contraction.
[0002]Enabling useful energy from the effect of thermal expansion and contraction has been widely used through history, and in particular in the steam age where water is boiled and the resultant vapour is used to power turbines or the like to be harnessed as kinetic energy and transferred into a desired energy form. Whilst this is effective, there is a significant associated amount of wasted energy.
[0003]The present invention aims to utilise the properties of expansion and contraction of a fluid and in particular accelerated condensation of a vapour and provides useable energy based on these properties in the form of mechanical motion which can then be used to create an electrical output.
[0004]According to the present invention, there is a system for driving a turbine, the system comprising a conduit and a chamber, the conduit defining a fluid flow path within which said turbine is located, said conduit being in communication with an inlet to said chamber, the system further comprising a piston mounted in said chamber so as to define an enclosure within said chamber and means to move said piston in a first direction within said chamber causing expansion of said enclosure, and heating means for heating fluid within said enclosure so as to cause expansion of said fluid into said enclosure, and condensing means for condensing said fluid so as to cause contraction of said enclosure and corresponding movement of said piston in a second, opposite direction within said chamber, thereby creating a suction force at said inlet of said chamber and drawing fluid through said conduit and across said turbine.
[0005]The system preferably further comprises a control means arranged to switch the power to the heating means off at a predetermined point. The control means is arranged to determine a preselected movement of the piston in a first direction such that once said piston has moved a preselected distance a signal is transmitted to turn the heating means off. The means to determine a preselected distance moved preferably comprises a laser beam. The heating means preferably comprises an electric heating element. The heating element is preferably located within the chamber in order to improve efficiency.
[0006]The condensing means is preferably mounted in the enclosure. The condensing means is preferably independently moveable of the piston, and may be shaped and configured to comprise an uneven surface area. This provides a greater surface area on which vapour may condense, thereby improving efficiency. However, it will be appreciated any configuration of condenser may be used to improve efficiency in this regard.
[0007]The condensing means is also preferably releasably attached to the piston when the piston is moving in said first direction. However, once the piston has moved a preselected distance in said first direction there is provided means to release the condenser from said piston. Alternatively, the condenser may be pushed down by an external means which accelerates condensation of the vapour and thus adds to the speed with which the piston also moves. Therefore, the system may further comprise a means to force the condensing means through the enclosure.
[0008]The means to move said piston in a first direction preferably comprises a second chamber having an inlet in fluidic connection with said conduit, the system further comprising a second piston mounted in said second chamber so as to define a second enclosure within said second chamber, heating means for heating fluid to expand said fluid into said second enclosure, and a second condensing means for condensing said fluid so as to cause contraction of said second enclosure and corresponding movement of said piston in a direction to decrease the volume of said second enclosure, thereby creating a suction force at said inlet of said chamber and drawing fluid through said conduit and across said turbine and thereby causing corresponding movement of said piston within said chamber in said first direction.
[0009]In this embodiment of the present invention, fluid will pass across the turbine in two directions, however it is preferable that a system of one way valves is provided such that flow is altered to reach the turbine in one direction, irrespective of the direction of travel of the fluid flow through said conduit.
[0010]The arrangement having two opposing chambers ensures energy is constantly applied to drive the turbine, and the action of each chamber causes a reaction in the opposing chamber. Preferably, the control means is arranged and configured to switch on the heating means in one chamber and switch off the heating means in the opposite chamber substantially simultaneously, i.e. in complementary fashion.
[0011]Also according to the present invention, there is a method of driving a turbine comprising the steps of providing a conduit and a chamber, the conduit defining a fluid flow path within which said turbine is located, said conduit being in communication with an inlet to said chamber, further providing a piston mounted in said chamber so as to define an enclosure within said chamber, further providing means to move said piston in a first direction within said chamber so as to enlarge said enclosure, heating the fluid within said enclosure so as to cause expansion of said fluid to fill said enclosure, and condensing said fluid by a condensing means passing through said enclosure so as to cause contraction of said fluid and corresponding movement of said piston in a second, opposite direction within said chamber, thereby creating a suction force at said inlet of said chamber and drawing fluid through said conduit and across said turbine.
[0012]The present invention will now be described with reference to the accompanying drawing in which:
[0013]FIG. 1 is a schematic side view of the apparatus according to the present invention.
[0014]Referring to FIG. 1, there are cylinders 2, 4 interconnected by a conduit 6 containing a fluid. The fluid must be able to flow and is preferably water. A heating element 8 is positioned at the bottom of each cylinder 2, 4 secured by an airtight seal. A liquid such as water is added into the cylinders 2, 4 of sufficient depth to at least cover the heating elements 8 in order to prevent damage thereto, and of a quantity great enough that when it substantially all vaporises it generates a volume of gas that provides enough pressure on the underside of the piston and/or condenser to force it to a maximum allowable limit. In order to set the system up, both of the heating elements are turned on and the liquid boiled to turn from liquid to vapour. Any excess pressure may be released by valves (not shown) in the piston 10 to ensure the correct initial volume of water in the cylinder 2,4, and all air in the cylinders 2, 4 has been released, and prevent build up of pressure within the cylinder 2,4. At this point the pistons 10 have risen due to the increased pressure, but they will then fall due to the condensation of the vapour as it contacts the condenser 12. The area above the pistons is then filled with water. The valve (not shown) should be opened and both heating elements 8 switched on and the water below the piston boiled. This pushes the pistons 10 upwards. When the pistons have traveled through approximately half of their full range, the valve is closed and power is transferred from both heating elements 8 to alternate heating as described in detail below.
[0015]The heating element 8 may be controlled by varying the amount of voltage applied to the heating elements 8. This enables careful control of the energy consumed and the amount of heat supplied by the heating elements.
[0016]In use and preferably once set up as described above (to optimise efficiency), one of the heating elements 8 is turned on, and the water in the cylinder is boiled, changing state from liquid to gas and causing an associated expansion in volume. The action will be described with reference to cylinder 4, however the mechanism is identical with respect to cylinder 2. This first change of state from liquid to gas and the associated expansion causes a positive pressure which pushes on piston 10 which is releasably connected to condenser 12, therefore both rise within the cylinder 4 such that the system maintains the pressure within the enclosure 18. The movement of the piston maintains the pressure in the enclosure 18 at a constant level. A control mechanism 14 may be provided which ensures the piston does not travel beyond a predetermined point. However, if the correct volume of water is in the cylinder originally or after the setting up procedure, then again efficiency of the system is increased. This control mechanism 14 may comprise a laser beam directed into a light detector, for example a photodiode in a circuit supporting voltaic mode of operation, which is broken by the piston at the top extent of the travel. At this time, the heating element 8 is switched off, and the heating element 8 in the corresponding cylinder 2 is switched on. Simultaneously, the condenser 12 is released from the piston 10. The condenser 12 falls under gravity and due to the natural condensing of the vapour due to the heat being turned off. The condenser is shaped to provide optimum condensing performance by providing an increased surface area, so may therefore provided with a plurality of fins to improve the condensing ability. However, it will be appreciated that numerous shapes and configurations of condenser 12 are possible. In one embodiment of the present invention, there is further provided a means to force the condenser through the vapour to increase the speed in which vapour turns to liquid (not shown). This will increase the speed at which the vapour is condensed, and therefore increase the suction of the fluid above the piston as described in more detail below. Arrow 16 indicates the direction of movement of the piston 10 and condenser 12 in the cylinder 2,4.
[0017]As the condenser 12 drops, and aids change of state from gas to liquid of the vapour, there is an associated reduction in volume. The condenser 12 creates a partial vacuum behind it as it falls, and therefore draws the piston with it down in the cylinder 4. This is the primary mechanism by which the apparatus functions, therefore does not rely heavily on the expansion of the water turning from liquid to gas below the piston to push each piston. Therefore, both pushing and pulling of the piston is achieved, pushing from below due to liquid turning to vapour, and drawing from above as the liquid is sucked back by the corresponding piston in the other cylinder dropping due to the condensation achieved. Once the system is running, then the heating of the water is only really used to facilitate production of the vapour to fill the gap caused by the piston being pulled by the opposing complementary cylinder 2,4. Utilising this system reduces the energy required to be put into the system to maintain it in use. It is envisaged that if fully thermally insulated, the system would fall into a state of equilibrium where the heating element would not need to be used.
[0018]The return power to be utilised by the system may be extracted in any suitable manner, such as an impeller driven by the liquid flow in the conduit 6. In a preferred embodiment, the flow is directed to the impeller via a system of one way valves and then fed onto the impeller. However, it is possible to also allow the flow to be harnessed in both directions.
[0019]The present invention has been described by way of example only and it will be appreciated by a person skilled in the art that variations and modifications may be made to the present invention without departing from the scope of protection afforded by the appended claims.
Claims:
1. A system for driving a turbine, the system comprising a conduit and a
chamber, the conduit defining a fluid flow path within which said turbine
is located, said conduit being in communication with an inlet to said
chamber, the system further comprising a piston mounted in said chamber
so as to define an enclosure within said chamber and means to move said
piston in a first direction within said chamber causing expansion of said
enclosure, and heating means for heating fluid within said enclosure so
as to cause expansion of said fluid into said enclosure, and condensing
means for condensing said fluid so as to cause contraction of said
enclosure and corresponding movement of said piston in a second, opposite
direction within said chamber, thereby creating a suction force at said
inlet of said chamber and drawing fluid through said conduit and across
said turbine.
2. A system according to claim 1 further comprising a control means arranged to switch said heating means off at a predetermined time.
3. A system according to claim 2, wherein said control means is arranged to determine a preselected movement of the piston in a first direction such that once said piston has moved a preselected distance a signal is transmitted to turn said heating means off.
4. A system according to claim 3, wherein the means to determine a preselected distance moved by said piston comprises a laser beam.
5. A system according to claim 1, wherein the heating means comprises an electric heating element.
6. A system according to claim 1, wherein said condensing means is mounted in said enclosure.
7. A system according to claim 1, wherein said condensing means is independently moveable of the piston.
8. A system according to any of claims 1, wherein said condensing means is releasably attached to the piston when the piston is moving in said first direction.
9. A system according to claim 8 further comprising means to release the condenser from said piston.
10. A system according to claim 1 further comprising means to force the condensing means through the enclosure.
11. A system according to claim 1 wherein said means to move said piston in a first direction preferably comprises a second chamber having an inlet in fluidic connection with said conduit, the system further comprising a second piston mounted in said second chamber so as to define a second enclosure within said second chamber, heating means for heating fluid to expand said fluid into said second enclosure, and a second condensing means for condensing said fluid so as to cause contraction of said second enclosure and corresponding movement of said piston in a direction to decrease the volume of said second enclosure, thereby creating a suction force at said inlet of said chamber and drawing fluid through said conduit and across said turbine and thereby causing corresponding movement of said piston within said chamber in said first direction.
12. A system according to claim 11 further comprising means to provide said fluid flow to reach the turbine in one direction, irrespective of the direction of travel of the fluid flow through said conduit.
13. A system according to claim 2, wherein the control means is arranged and configured to switch on the heating means in one chamber and switch off the heating means in the opposite chamber substantially simultaneously.
14. A method of driving a turbine comprising the steps of providing a conduit and a chamber, the conduit defining a fluid flow path within which said turbine is located, said conduit being in communication with an inlet to said chamber, further providing a piston mounted in said chamber so as to define an enclosure within said chamber, further providing means to move said piston in a first direction within said chamber so as to enlarge said enclosure, heating the fluid within said enclosure so as to cause expansion of said fluid to fill said enclosure, and condensing said fluid by a condensing means passing through said enclosure so as to cause contraction of said fluid and corresponding movement of said piston in a second, opposite direction within said chamber, thereby creating a suction force at said inlet of said chamber and drawing fluid through said conduit and across said turbine.
15. (canceled)
Description:
[0001]The present invention relates to the an engine utilising the power
of vacuum's thermal expansion and contraction.
[0002]Enabling useful energy from the effect of thermal expansion and contraction has been widely used through history, and in particular in the steam age where water is boiled and the resultant vapour is used to power turbines or the like to be harnessed as kinetic energy and transferred into a desired energy form. Whilst this is effective, there is a significant associated amount of wasted energy.
[0003]The present invention aims to utilise the properties of expansion and contraction of a fluid and in particular accelerated condensation of a vapour and provides useable energy based on these properties in the form of mechanical motion which can then be used to create an electrical output.
[0004]According to the present invention, there is a system for driving a turbine, the system comprising a conduit and a chamber, the conduit defining a fluid flow path within which said turbine is located, said conduit being in communication with an inlet to said chamber, the system further comprising a piston mounted in said chamber so as to define an enclosure within said chamber and means to move said piston in a first direction within said chamber causing expansion of said enclosure, and heating means for heating fluid within said enclosure so as to cause expansion of said fluid into said enclosure, and condensing means for condensing said fluid so as to cause contraction of said enclosure and corresponding movement of said piston in a second, opposite direction within said chamber, thereby creating a suction force at said inlet of said chamber and drawing fluid through said conduit and across said turbine.
[0005]The system preferably further comprises a control means arranged to switch the power to the heating means off at a predetermined point. The control means is arranged to determine a preselected movement of the piston in a first direction such that once said piston has moved a preselected distance a signal is transmitted to turn the heating means off. The means to determine a preselected distance moved preferably comprises a laser beam. The heating means preferably comprises an electric heating element. The heating element is preferably located within the chamber in order to improve efficiency.
[0006]The condensing means is preferably mounted in the enclosure. The condensing means is preferably independently moveable of the piston, and may be shaped and configured to comprise an uneven surface area. This provides a greater surface area on which vapour may condense, thereby improving efficiency. However, it will be appreciated any configuration of condenser may be used to improve efficiency in this regard.
[0007]The condensing means is also preferably releasably attached to the piston when the piston is moving in said first direction. However, once the piston has moved a preselected distance in said first direction there is provided means to release the condenser from said piston. Alternatively, the condenser may be pushed down by an external means which accelerates condensation of the vapour and thus adds to the speed with which the piston also moves. Therefore, the system may further comprise a means to force the condensing means through the enclosure.
[0008]The means to move said piston in a first direction preferably comprises a second chamber having an inlet in fluidic connection with said conduit, the system further comprising a second piston mounted in said second chamber so as to define a second enclosure within said second chamber, heating means for heating fluid to expand said fluid into said second enclosure, and a second condensing means for condensing said fluid so as to cause contraction of said second enclosure and corresponding movement of said piston in a direction to decrease the volume of said second enclosure, thereby creating a suction force at said inlet of said chamber and drawing fluid through said conduit and across said turbine and thereby causing corresponding movement of said piston within said chamber in said first direction.
[0009]In this embodiment of the present invention, fluid will pass across the turbine in two directions, however it is preferable that a system of one way valves is provided such that flow is altered to reach the turbine in one direction, irrespective of the direction of travel of the fluid flow through said conduit.
[0010]The arrangement having two opposing chambers ensures energy is constantly applied to drive the turbine, and the action of each chamber causes a reaction in the opposing chamber. Preferably, the control means is arranged and configured to switch on the heating means in one chamber and switch off the heating means in the opposite chamber substantially simultaneously, i.e. in complementary fashion.
[0011]Also according to the present invention, there is a method of driving a turbine comprising the steps of providing a conduit and a chamber, the conduit defining a fluid flow path within which said turbine is located, said conduit being in communication with an inlet to said chamber, further providing a piston mounted in said chamber so as to define an enclosure within said chamber, further providing means to move said piston in a first direction within said chamber so as to enlarge said enclosure, heating the fluid within said enclosure so as to cause expansion of said fluid to fill said enclosure, and condensing said fluid by a condensing means passing through said enclosure so as to cause contraction of said fluid and corresponding movement of said piston in a second, opposite direction within said chamber, thereby creating a suction force at said inlet of said chamber and drawing fluid through said conduit and across said turbine.
[0012]The present invention will now be described with reference to the accompanying drawing in which:
[0013]FIG. 1 is a schematic side view of the apparatus according to the present invention.
[0014]Referring to FIG. 1, there are cylinders 2, 4 interconnected by a conduit 6 containing a fluid. The fluid must be able to flow and is preferably water. A heating element 8 is positioned at the bottom of each cylinder 2, 4 secured by an airtight seal. A liquid such as water is added into the cylinders 2, 4 of sufficient depth to at least cover the heating elements 8 in order to prevent damage thereto, and of a quantity great enough that when it substantially all vaporises it generates a volume of gas that provides enough pressure on the underside of the piston and/or condenser to force it to a maximum allowable limit. In order to set the system up, both of the heating elements are turned on and the liquid boiled to turn from liquid to vapour. Any excess pressure may be released by valves (not shown) in the piston 10 to ensure the correct initial volume of water in the cylinder 2,4, and all air in the cylinders 2, 4 has been released, and prevent build up of pressure within the cylinder 2,4. At this point the pistons 10 have risen due to the increased pressure, but they will then fall due to the condensation of the vapour as it contacts the condenser 12. The area above the pistons is then filled with water. The valve (not shown) should be opened and both heating elements 8 switched on and the water below the piston boiled. This pushes the pistons 10 upwards. When the pistons have traveled through approximately half of their full range, the valve is closed and power is transferred from both heating elements 8 to alternate heating as described in detail below.
[0015]The heating element 8 may be controlled by varying the amount of voltage applied to the heating elements 8. This enables careful control of the energy consumed and the amount of heat supplied by the heating elements.
[0016]In use and preferably once set up as described above (to optimise efficiency), one of the heating elements 8 is turned on, and the water in the cylinder is boiled, changing state from liquid to gas and causing an associated expansion in volume. The action will be described with reference to cylinder 4, however the mechanism is identical with respect to cylinder 2. This first change of state from liquid to gas and the associated expansion causes a positive pressure which pushes on piston 10 which is releasably connected to condenser 12, therefore both rise within the cylinder 4 such that the system maintains the pressure within the enclosure 18. The movement of the piston maintains the pressure in the enclosure 18 at a constant level. A control mechanism 14 may be provided which ensures the piston does not travel beyond a predetermined point. However, if the correct volume of water is in the cylinder originally or after the setting up procedure, then again efficiency of the system is increased. This control mechanism 14 may comprise a laser beam directed into a light detector, for example a photodiode in a circuit supporting voltaic mode of operation, which is broken by the piston at the top extent of the travel. At this time, the heating element 8 is switched off, and the heating element 8 in the corresponding cylinder 2 is switched on. Simultaneously, the condenser 12 is released from the piston 10. The condenser 12 falls under gravity and due to the natural condensing of the vapour due to the heat being turned off. The condenser is shaped to provide optimum condensing performance by providing an increased surface area, so may therefore provided with a plurality of fins to improve the condensing ability. However, it will be appreciated that numerous shapes and configurations of condenser 12 are possible. In one embodiment of the present invention, there is further provided a means to force the condenser through the vapour to increase the speed in which vapour turns to liquid (not shown). This will increase the speed at which the vapour is condensed, and therefore increase the suction of the fluid above the piston as described in more detail below. Arrow 16 indicates the direction of movement of the piston 10 and condenser 12 in the cylinder 2,4.
[0017]As the condenser 12 drops, and aids change of state from gas to liquid of the vapour, there is an associated reduction in volume. The condenser 12 creates a partial vacuum behind it as it falls, and therefore draws the piston with it down in the cylinder 4. This is the primary mechanism by which the apparatus functions, therefore does not rely heavily on the expansion of the water turning from liquid to gas below the piston to push each piston. Therefore, both pushing and pulling of the piston is achieved, pushing from below due to liquid turning to vapour, and drawing from above as the liquid is sucked back by the corresponding piston in the other cylinder dropping due to the condensation achieved. Once the system is running, then the heating of the water is only really used to facilitate production of the vapour to fill the gap caused by the piston being pulled by the opposing complementary cylinder 2,4. Utilising this system reduces the energy required to be put into the system to maintain it in use. It is envisaged that if fully thermally insulated, the system would fall into a state of equilibrium where the heating element would not need to be used.
[0018]The return power to be utilised by the system may be extracted in any suitable manner, such as an impeller driven by the liquid flow in the conduit 6. In a preferred embodiment, the flow is directed to the impeller via a system of one way valves and then fed onto the impeller. However, it is possible to also allow the flow to be harnessed in both directions.
[0019]The present invention has been described by way of example only and it will be appreciated by a person skilled in the art that variations and modifications may be made to the present invention without departing from the scope of protection afforded by the appended claims.
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