Abstract
Disclosed herein is a device for active temperature control and mobile transportation, including a fluid for regulating a temperature of the device, a pump for circulating the fluid, at least one Peltier device for heating or cooling a heat exchange unit being fluidly connected to the fluid, a temperature sensor for measuring a current temperature of the device, a detection module for determining an error value of the current temperature from a predetermined temperature value. The error value may be positive or negative, and a switching device can activate the at least one Peltier device to cool the heat exchange unit when the error is one sign and heat the heat exchange unit when the error value is the opposite sign. A power supply is electrically coupled to the pump, the Peltier device, the temperature sensor, the detection module, and the switching device.
Claims
1. A device for active temperature control and mobile transportation, the device comprising: a fluid for regulating a temperature of the device; a pump for circulating the fluid; at least one Peltier device for heating or cooling a heat exchange unit, the heat exchange unit being fluidly connected to the fluid; a temperature sensor for measuring a current temperature of at least one of: the fluid, a portion of the fluid in the heat exchange unit, the heat exchange unit, and an area of the device; a detection module for determining an error value of the current temperature from a predetermined temperature value; a switching device for activating the at least one Peltier device, wherein when the error value has a first sign the at least one Peltier device cools the heat exchange unit, and when the error value has a second sign, opposite to the first sign, the at least one Peltier device heats the heat exchange unit; and a power supply electrically coupled to the pump, the Peltier device, the temperature sensor, the detection module, and the switching device.
2. The device of claim 1, where the fluid includes at least one of: water and propylene glycol.
3. The device of claim 1, wherein the temperature sensor comprises a thermocouple, a thermistor, or a thermometer.
4. The device of claim 1, wherein the detection module comprises a device which determines the error value and communicates with the switching device.
5. The device of claim 1, further comprising: a microcontroller for analyzing the error value and controlling the Peltier device or the switching device.
6. The device of claim 5, wherein the microcontroller uses a formula: to calculate a drive current of the Peltier device, wherein e is the error value and Kp, Ki, and Kd are constant coefficients.
7. The device of claim 1, wherein the switching device includes at least one of: an amplifier, a high current switch, an H-bridge, a relay, and a contactor.
8. The device of claim 1, wherein the predetermined temperature value is preset and static.
9. The device of claim 1, wherein the predetermined temperature value is dynamic.
10. The device of claim 9, further comprising: a display coupled to the switching device, wherein a user can set the predetermined temperature value using an input of the display.
11. The device of claim 1, further comprising a fluid circulation unit fluidly connected to the fluid and the pump.
12. The device of claim 11, wherein the fluid circulation unit includes a set of tubes in a pattern for circulating the fluid.
13. The device of claim 11, wherein the fluid circulation unit comprises a material with a pattern of channels formed throughout the material.
14. The device of claim 11, further comprising: a containment unit for holding an object, the containment unit being capable of holding the fluid circulation unit.
15. The device of claim 14, wherein the containment unit comprises a bag including a closure device and a liner.
16. The device of claim 14, wherein the object is a body part.
17. The device of claim 16, wherein the predetermined temperature value is approximately 40° F.
18. The device of claim 1, wherein the predetermined temperature value is between approximately 28° F. and approximately 52° F.
19. The device of claim 18, wherein the predetermined temperature value is between approximately 35° F. and approximately 45° F.
20. The device of claim 20, wherein the device is configured for transporting a body part and the predetermined temperature is approximately 40° F.
21. The device of claim 1, further comprising: a battery for providing power to the power supply, wherein the battery operates at 120V or 12V and can provide up to 4 hours of power.
Description
BRIEF DESCRIPTION OF THE FIGURES
[0006] FIG. 1 illustrates a schematic view of a transportation device according to some embodiments.
[0007] FIG. 2 illustrates an exploded view of a heat exchange unit according to some embodiments.
[0008] FIG. 3 illustrates a diagram of a method according to some embodiments.
[0009] FIG. 4 illustrates a schematic view of a transportation device according to some embodiments.
[0010] FIG. 5 illustrates a diagram of a method according to some embodiments.
[0011] FIG. 6 illustrates an exploded view of a transportation device according to some embodiments.
[0012] FIG. 7 illustrates an exploded view of a containment unit according to some embodiments.
[0013] It is noted that the drawings may not be to scale. The drawings are intended to depict only typical aspects of the invention, and therefore should not be considered as limiting the scope of the invention. In the drawings, like numbering represents like elements between the drawings. The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0014] Disclosed herein is a device for active temperature control during mobile transportation of an article or an object. Turning to FIG. 1, device 100, according to some embodiments, includes a fluid 102 for regulating a temperature of device 100, which is achieved by actively controlling the temperature of fluid 102 and circulating fluid 102 throughout some or all of device 100. Fluid 102 may include any liquid or liquid like substance capable of being circulated. It should be understood that fluid 102 may include a gas, or may phase between liquid and gas during circulation. Fluids which retain heat or cold for longer periods of time can benefit the effectiveness of device 100. In some embodiments, fluid 102 may include water, propylene glycol, and now known or later developed refrigerant substances. Device 100 may also include a pump 104 for circulating fluid 102 throughout portions of device 100. Further details of the circulation of fluid 102 are disclosed below.
[0015] Still referring to FIG. 1, device 100 may also include at least one Peltier device 106 for heating or cooling fluid 102, either directly or indirectly. As should be clear to one of skill in the art, a Peltier device can include any now known or later developed Peltier heat pumps, solid state refrigerators, thermoelectric coolers (TEC), or any other solid state device capable of heating, cooling, or both. In some embodiments, one Peltier device 106 may be used for heating and another Peltier device 106 may be used for cooling. In another embodiment, a single or multiple Peltier devices 106 may be used, each capable of both heating and cooling. In still further embodiments, any combination of Peltier devices 106 which heat, cool, or both may be used together. While solid state refrigerants are described, it should be clear to one of ordinary skill in the art that standard refrigeration utilizing a compressor and refrigerant could be used in place of a Peltier device as well, and is included in the scope of the invention.
[0016] Still referring to FIG. 1, in some embodiments, at least one Peltier device 106 is attached to a surface of a heat exchange unit 108. Peltier device(s) 106 may be secured to heat exchange unit 108 by glue, epoxy, or a fastener, so long as heating and cooling supplied by Peltier device 106 does not cause separation from heat exchange unit 108. Heat exchange unit 108 is fluidly connected to fluid 102, in some embodiments directly from pump 104. Heat exchange unit 108 may include any material which acts as an efficient conductor of heat and cooling from Peltier device 106 to fluid 102. For instance, in some embodiments, heat exchange unit 108 comprises any metal that efficiently conducts and evenly distributes heating or cooling across heat exchange unit 108, and can include but is not limited to cast aluminum and anodized aluminum.
[0017] Turning to FIG. 2, an example heat exchange unit 108 is shown which includes a water block style of design. In these embodiments, heat exchange unit 108 may include a back piece 202 and a front piece 204 with corresponding channels 206, although a solid block could be utilized as well. Any number of paths may be used for channels 206 such that fluid 102 can reach desired temperatures in an appropriate amount of time based on the flow rate through heat exchange unit 108. Front piece 204 may include an inlet 208 for receiving fluid 102 from pump 104 (FIG. 1), and an outlet 210 for supplying fluid 102 to other portions of device 100 (FIG. 1), as will be described further below. Heat exchange unit 108 may be formed as illustrated in FIG. 2 by casting, molding, or milling an appropriate conducting material. Fans 212 may be included on heat exchange unit 108 to increase the consistency of heat or cooling provided by Peltier device 106, or to assist in heating or cooling Peltier device 106. Front piece 204 and back piece 202 may be adhered together using any strong adhesive that resists damage from exposure to water and which reduces the risk of leaking, for instance silicone adhesives. Heat exchange unit 108 may also include one or more heatsink structures (not pictured), which in some embodiments may be under or near fans 212. In some embodiments, heat exchange unit 108 may be disposable, in case of fear of contamination of fluid 102.
[0018] Returning to FIG. 1, a temperature sensor 110 may be included in or on heat exchange 108, along the flow of fluid 102, or anywhere in device 100 where a variance of temperature may be expected. Temperature sensor 110 may be used for measuring a current temperature of at least one of: fluid 102 generally, a portion of fluid 102 in heat exchange unit 108, at any surface of heat exchange unit 108, and an area of device 100, including any open areas of device 100. It should be understood that more than one temperature sensor 110 may be used in conjunction with one another, either taking individual temperature readings or averaging the readings of each. Any number of temperature sensor(s) 110 may be used. Additionally, temperature sensor 110 may include any device capable of taking temperature readings, including but not limited to a thermocouple, a thermistor, and a thermometer.
[0019] Still referring to FIG. 1, device 100 may include a detection module 112, which communicates with temperature sensor 110, for determining an error value of the current temperature from a predetermined temperature value. In some embodiments, the error value may be a positive value or a negative value, representing a higher temperature than desired or a lower temperature than desired, respectively. Detection module 112 may include any device which can determine, from a reading of temperature sensor 110, an error value and communicate with a switching device 114. Switching device 114 may include an amplifier, a high current switch, an H-bridge, a relay, or a contactor, and may in some embodiments include MOSFET devices. The list of switching device 114 is not exhaustive, any device may be included as switching device 114 which can activate Peltier device 106, and may include bi-directional devices.
[0020] In some embodiments, detection module 112 communicates between temperature sensor 110 and switching device 114 such that when the error value has a first sign, which in some embodiments is positive, Peltier device 106 cools heat exchange unit 108, and when the error value has a second sign that is opposite to the first sign, which in some embodiments is negative, Peltier device 106 heats heat exchange unit 108.
[0021] Device 100 also includes a power supply 116 coupled to pump 104, any Peltier device(s) 106, temperature sensor 110, detection module 112, and switching device 114. Power supply 116 may operate from a battery 118. Battery 118 can include any battery capable of operating at 120V (wall plug) or 12V (cigarette lighter, etc.), and should be able to provide at least 4 hours of power to power supply 116. Additionally, in some embodiments, battery 118 should have no fade, such as a 10aH-25 W continuous battery. Battery 118 may include LiPo, lithium iron phosphate (LiFePO.sub.4), lithium cobalt oxide (LiCoO.sub.2), nickel cadmium, lead acid, and any other battery now known or later developed. Power supply 116 may also operate from any other source of power. For instance, device 100 may be able to be plugged into a wall outlet, a vehicle outlet, or direct wired into wiring. When plugged in, power supply 116 can convert the energy provided to operate each component of device 100 requiring power, and in some embodiments, may charge battery 118 via any charging means necessary. In further embodiments, when plugged in, device 100 stays in a sleep mode and only charges battery 118 for future use of device 100, for instance via a trickle charge technique.
[0022] In some embodiments, similar to those described above, switching device 114 switches Peltier device 106 on or off for heating or cooling based on the error value. As shown in FIG. 3, a method 300 is disclosed, which is sometimes called the “Bang Bang” control method. For instance, at step 302 the process begins. At step 304 temperature sensor 110 reads the temperature of fluid 102 or heat exchange unit 108. At step 306, detection module 112 determines the error value and at step 308, determines if a magnitude of the error is greater than a threshold, for instance a hysteresis constant. If not, at step 310, switching device 114 sets Peltier device 106 to zero, or off, and returns to step 302 in a predetermined amount of time before running method 300 again.
[0023] If at step 308 the error value exceeds the threshold, detection module 112 determines if the error value is a first sign or a second sign, such as positive or negative, at step 312. If a first sign, at step 314 Peltier device 106 is set to a negative current, effectively cooling heat exchange unit 108 to reduce the error value towards zero. If a second sign, opposite the first sign, meaning that the temperature is lower than the predetermined temperature value, at step 316 switching device 114 sets a positive current for Peltier device 106 in order to heat fluid 102 in order to reach the predetermined temperature value.
[0024] Turning to FIG. 4, device 100, otherwise identical to that of FIG. 1, may further include a microcontroller 120 for analyzing the error value from detection module 114 and for controlling Peltier device 106. The further use of a microcontroller can still be used for method 300 (FIG. 3) as above, but can also allow for more subtle control of device 100. For instance, using microcontroller 120, a proportional control method may be implemented that allows for variable heating and/or cooling of device 100. Microcontroller 120 may be any MOSFET devices, H-Bridges, or high current drivers.
[0025] Turning to FIG. 5, a proportional control method 500 is described in greater detail. At step 502, the process begins. At step 504, temperature sensor 110 acquires a current temperature at any location of device 100 desired. At step 506, detection module 112 calculates an error value from a predetermined temperature value. At step 508, microcontroller 120 calculates an output drive current for Peltier device 106 (FIG. 4) using a set of variables. At step 510, microcontroller 120 (FIG. 4) adjusts the drive current of Peltier device 106 and returns to step 502 until a predetermined amount of time has passed before running process 500 again.
[0026] Still referring to FIGS. 4 and 5, microcontroller 120 in step 508 can implement a number of variables for determining the drive necessary for Peltier device 106. For instance, the error value may include an error ‘e’, and using error e, Formula I may be used to calculate the drive current of the Peltier device 106. In such embodiments, Kp, Ki, and Kd are constant coefficients that are used to tune the response of the system, and are set based on the parameters of the specific configuration of the system.
[00001]
[0027] In these embodiments, microcontroller 120 is used to calculate the output. In this some embodiments, an integral term can be calculated by using an accumulator variable that is persistent for multiple iterations of the control loop of process 500 (FIG. 5), and the derivative term is implemented with a persistent ‘last value’ variable. The output of device 100 (FIG. 4) can include a digital to analog converter (DAC), a pulse width modulated signal (PWM), a pseudo random sequence (PRS), or other now known or later developed schemes for outputting an analog value. Similar to method 300 (FIG. 3) described above, in order to allow for both heating and cooling of device 100, the analog value must be allowed to represent both positive and negative values.
[0028] While described as separate components, it should be understood that one or all of detection module 112, switching device 114, power supply 116, and microcontroller 120 may be embodied in a single device, such as a PCB controller or motherboard of an electronic device. Additionally, any number of electronic components required to work device 100, whilst not described in detail, may be included in device 100, including but not limited to transformers, rectification diodes, resistors, additional wiring, N-FETs, P-FETs, or other drivers, adapters, and connectors.
[0029] In either method 300 (FIG. 3) or method 500 (FIG. 5), the predetermined temperature value may be preset and static for device 100 (FIG. 1). In embodiments where the predetermined temperature value is static, it may be set by the manufacturer or factory of device 100 or any component of device 100. In some embodiments, the predetermined temperature value may be dynamic. In these embodiments, device 100 may further include a display 122 (FIG. 4) coupled to at least switching device 114. Display 122 may include any display, including but not limited to LED, LCD, OLED, plasma, and electroluminescent panels. When display 122 is included, a user of device 100 may be able to use an input 124, such as a touchscreen portion of display 122, to set the predetermined temperature manually, turn device 100 on or off, or activate any features of device 100. Input 124 may include a touchscreen that is activated by capacitance, pressure, or any other ‘touch’ methods. Additionally, display 122 may include a battery monitor showing remaining charge and/or life of battery 118. Input 124 may be a portion of display 122, or the entirety of display 122. Additionally, input 124 may include controls external to display 122 in the form of buttons, knobs, or similar controls, and can also include pressure sensitive buttons integrated into display 122 or around display 122, such that the buttons appear to be a part of the screen, but are analog, pressure sensitive buttons.
[0030] Each component of FIG. 1 and FIG. 4 may be included inside a portable unit 126, with display 122, if included, on a surface of portable unit 126. Each above described component can be included in a small package to be reused as part of device 100. In some embodiments, turning to FIG. 6, device 100, containing any or all components described above within portable unit 126, may further comprise a fluid circulation unit 128 fluidly connected to fluid 102 from pump 104. Any means of connecting fluid circulation unit 128 fluidly to pump 104 of portable unit 126 may be used, including being permanently attached or having a quick release valve or similar attachment. Fluid circulation unit 128 may be fluidly connected to pump 104 via a fluid inlet 130 for accepting fluid 102 and a fluid outlet 132 for returning fluid 102 to pump 104, and thus to heat exchange unit 108 for heating or cooling.
[0031] Still referring to FIG. 6, fluid circulation unit 128 may include a set of tubes 134 in a pattern for circulating fluid 102, and thus heating or cooling the area in or surrounding fluid circulation unit 128. Set of tubes 134 may include actual tubes, such as plastic or rubber tubing, patterned on a piece of material or by a rigid structure. In alternative embodiments, set of tubes 134 may include a system of channels formed throughout a material from which the fluid circulation unit 128 is made, such as by sewing a set of channels or gluing the material to form a set of channels, effectively creating set of tubes 134. In some embodiments, set of tubes 134 may be formed by using heat sealing or plastic welding of a material.
[0032] Still referring to FIG. 6, device 100 may further include, in some embodiments, a containment unit 136 for holding an object or article (not pictured). In some embodiments, containment unit 136 is designed to hold fluid circulation unit 128, such that fluid circulation unit 128 heats and cools the space inside containment unit 136, for instance in pockets specially designed to fit fluid circulation unit 128. In another embodiment, containment unit 136 and fluid circulation unit 128 or made from a single component and are not separable. In some embodiments, containment unit 136 may roll to conserve space. Additionally, some insulation may be provided around containment unit 136, adding a layer of padding as well as increasing the efficiency of temperature control within. Containment unit 136, when attached to portable unit 126, may roll up next to portable unit 126, or it may wrap around or otherwise surround portable unit 126. In some embodiments, buckles attached to straps or other attachment means (not pictured) may be used to secure containment unit 136 to portable unit 126 until use. Additionally, portable unit 126 could include an enclosure space for inserting containment unit 136 inside of portable unit 126. In some embodiments, containment unit 136 may be held in place by vacuum seal in a package to be opened when used.
[0033] Turning to FIG. 7, in some embodiments, containment unit 136 comprises a bag. The bag may include a closure device 138 and a liner 140, wherein liner 140 may be removable so as to be disposed of in order to reuse containment unit 136. In alternative embodiments, containment unit 136 may be disposable, such that only portable unit 126 is kept after use of device 100. Closure device 138 may include a zipper, a ziplock type sliding zipper, or any other means of closing containment unit 136. Closure device 138 may extend across one side, multiple sides, or the entire perimeter of containment unit 136. Liner 140 can include plastic, rubber, nylon, or any material that will protect the inside of containment unit 136 from contamination or staining. Containment unit 136 may be made from any material, but in some embodiments should include a material resistant to tears, such as ripstop cotton or cotton and nylon blends, cotton, nylon, polyester, and other heavy duty canvas like materials. Additionally, it should be understood that containment unit 136 may be of any size or shape necessary for transportation of object 142. In some embodiments, multiple different containment units 136 may be included with device 100 which are interchangeable for different objects 142.
[0034] Still referring to FIG. 7, containment unit 136 may be soft or flexible in order to allow for a wider variety of objects 142 to be carried. In alternative embodiments, it may be rigid, or capable of becoming rigid when necessary to support object 142 and reduce unwanted movement. For instance, containment unit 136 may include an air pump 144 which can provide air or gas, or even a liquid, with enough pressure so as to inflate, support, or harden containment unit 136. Air pump 144 may also remove air to create a vacuum and harden containment unit 136. Thus, air pump 144 may include a vacuum pump capable of increasing or decreasing the pressure of containment unit 136. That is, air pump 144 can inflate and deflate, and may be controlled by switching device 114 and/or microcontroller 120. Air pump 144 may be included in containment unit 136, or alternatively, may be included in portable unit 126 or as an external system, either powered by power supply 116, battery 118, or an external power source.
[0035] Further regarding FIG. 7, alternatively, or in combination with air pump 144, one or more splints 146 may be included in containment unit 136, either in pockets or sewn or glued in. Splints 146 may also be attached to the outside of containment unit 136 via Velcro or other attachment methods. Splints 146 may be made of any rigid or semi-rigid material, and can be attached or inserted in any number as needed or permanently attached in any pattern and combination. Additionally, a soft or rigid insulation may be included as part of containment unit 136, providing a boost to the efficiency of temperature control as well as control of the rigidity or lack thereof of containment unit 136.
[0036] Containment unit 136 may be used to store any article or object requiring movement at a steady desired temperature. For instance, object 142 (FIG. 7) may include a body part, such as a human appendage, or any other body part, human or animal, including but not limited to limbs, organs, digits, blood, or an entire body. In accidents requiring or resulting in amputation, trauma amputation, or other limb removal, device 100 can be used to transport object 142 at a steady temperature without cellular damage due to exposure to ice, being too cold, cooling too quickly, or not being cooled sufficiently. For instance, where object 142 is a body part, the predetermined temperature value may be approximately 40 degrees Fahrenheit (° F.). Additionally, transport of a whole body in the case of severe accidents may be accomplished without extensive damage, for instance, after a skiing accident.
[0037] In alternative embodiments, object 142 may include any other object or article which is desired to be maintained at a predetermined temperature, including but not limited to beverages, food, medication, and other objects. In embodiments, the predetermined temperature value may thus be between approximately 28° F. and approximately 52° F., or more particularly between approximately 35° F. and approximately 45° F. In some embodiments, the predetermined temperature value includes approximately 40° F. It should be understood, though, that any temperature may be maintained, limited only by the range of Peltier device 106 (FIG. 1). As used herein, “approximately” can include plus or minus 5 from the given value.
[0038] Various embodiments described above give the ability to transport an object or article in a very mobile way while actively controlling the temperature around, and thus the temperature of, the object or article. For instance, a portable battery allows for movement of device 100 by carrying via a handle (not shown) on either portable unit 126 or containment unit 136 (FIG. 6), wherein the handle may be a cloth or nylon handle, a plastic handle, a metal handle, which may be formed as a part of device 100, secured to device 100, or otherwise included by any means possible. Additionally, various sorts of outlets and power can be used for longer term transportation. For instance, in a traffic accident, a paramedic, EMS provider, or any first responder could take device 100 from an ambulance, police car, or fire truck, pick up object 142 and process it and store in containment unit 136 until it is ready to go back on the ambulance, where device 100 could be plugged back in or left to run on remaining battery charge until arriving at a hospital. At this time, device 100 could be transported into the hospital on battery power and plugged in again when convenient. In order to allow for such mobility, device 100 may weigh less than approximately 20 pounds, and in some embodiments, less than approximately 15 pounds. In some embodiments, device 100 can be less than approximately 10 pounds.
[0039] The active temperature control of device 100 allows for close temperature control within a small window of variance, and the flow of fluid 102 allows for gradual cooling or gradual heating of object 142 so as not to quickly alter a temperature. Additionally, ambient temperature outside of containment unit 136 can be largely disregarded due to the ability of device 100 to both cool and heat with a high degree of accuracy, unlike many previous “temperature control” devices which frequently only heated or cooled, usually from a base ambient temperature. Typically, they provide a 40 degree Fahrenheit change from the ambient temperature, which clearly is typically either too warm or too cold, and does not have an actual ‘target’ temperature that it reaches.
[0040] Beside the above uses, device 100 and the related technology may also be useful for more than a containment unit as described. For instance, uses include but are not limited to: cold cap therapy (different design hats for kids, etc.), hunting or outdoor seating, venue seating, boat seats, seats and seat backs for office chairs, dog beds, beverage containers, lunch bags, beer bags, beach bags, backpacks for school or hiking, coffee or tea cups, field dress hunting bags, safari bags, and general purpose bags that are included with cars and trucks (for shopping trips, etc.). In some embodiments, blood or organs may be transported and kept at a target temperature in order to longer preserve them. In additional embodiments, device 100 could be used for the transportation of semen, either in human preservation or donation, or for agricultural uses such as artificial insemination (AI). In those embodiments, device 100 could simply include a pull tab to start the battery and include a hard containment unit 136 that can be wiped out for reuse, or entirely disposable. Thus, device 100 could be started and driven to the facility without any interruption in temperature of semen or any uncomfortable situations.
[0041] In another embodiment, device 100 can include a device specifically for warming and/or cooling of intravenous therapy or injection (IV). For instance, during cardiac arrest, an IV fluid can be used to reduce damage by chilling the fluid. Additionally, warm IV fluid can be used to assist in recovering from hypothermia, effectively warming a patient from the inside. IV fluid can include saline or any other fluid delivered intravenously.
[0042] In a further embodiment, device 100 could be designed for the transportation and storage of breast milk. Device 100 could eliminate the need to freeze breast milk, and reduce the temperature variations introduced whilst attempting to travel with a breast-feeding baby. Thus, the milk would be stored at better temperatures and increase the likelihood of a baby taking the milk.
[0043] The foregoing description of various aspects of the invention has been presented for the purpose of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and obviously, many modifications and variations are possible. Such variations and modifications that may be apparent to one skilled in the art are intended to be included within the scope of the present invention as defined by the accompanying claims.
