Abstract:
This invention presents three kinds of conceptual models of fluid pump with similar innovation, to design thin and small compartments and laterally link all compartments with flexible means so that the whole fluid pump is thin and flexible. The first one uses the concept of spiral peristaltic pump. The rollers on the thin and round rotator of the thin spiral type of peristaltic pump roll over a section of elastic tube to press out the fluid in the tube. The rotator may be driven by a thin motor, electromagnetic driver, or spring. The second one uses the concept of linear peristaltic pump. The thin motors or electromagnetic drivers press different places of a section of elastic tube or its variation in special sequence to press out the fluid in the tube. The third one uses the concept of distributed processor. It comprises a number of thin and small pumping units where each one uses the elastic force, compressed air, linear motor, or the electromagnetic device to press out limited amount of fluid in the container. The number of pumping units is appropriate so that the user carries enough fluid to be convenient. For all models, the pump is laterally integrated by linking thin and small compartments with flexible means. The pump is as thin as the compartments and is flexible as the compartments are small and are linked with flexible cables, tubes, and other linking means. So, the user will feel comfortable to carry the pump under their clothes or to attach it to the skin.

Description:
FIELD OF INVENTION  
       [0001]     The present invention relates to the thin and foldable fluid pump to be used in the apparatus that is carried under the user&#39;s clothes or is attached to the user&#39;s skin.  
                                                               Previous Arts                    U.S. Pat. No.   Inventor   Date               6854620   Ramey   Feb. 15, 2005       6699234   Yeh   Mar. 02, 2004       6659980   Moberg, et al.   Dec. 09, 2003       6656148   Das, et al.   Dec. 02, 2003       5961487   Davis   Oct. 05, 1999                    US patent application   Applicant   Date               20050159708   Sidler   Jul. 21, 2005       20050177111   Ozeri   Aug. 11, 2005       20050051580   Ramey   Mar. 10, 2005       20050020980   Inove   Jan. 27, 2005       20040133166   Moberg   Jul. 08, 2004       20050020978   Vollenweider   Jan. 27, 2005                 References            http://www.debiotech.com/debiotech.htm             
 
       BACKGROUND AND PRIOR ART  
       [0002]     Some patients, like type I diabetics, need medication continuously. The medication infusion pumps, or called insulin pumps, are ideal for them to reduce the number of injections. However, all the medication infusion systems in the market, like those made by Medtronic MiniMed, Disetronic, Deltec, Dana, and Animas, are about a cellular phone&#39;s size that are too thick. The systems developed recently, like those presented in the U.S. Pat. No. 6,854,620 by Ramey, U.S. Pat. No. 6,659,980 by Moberg, et al., U.S. Pat. No. 5,961,487 by Davis, and U.S. Pat. No. 6,656,148 by Das, et al., and in the US patent applications 20050177111 by Ozeri, 20050159708 by Sidler, 20050051580 by Ramey, 20050020980 by Inove et al., 20050020978 by Vollenweider, 20040133166, 20040085215, and 20030073954 by Moberg, and 20030233069 by Gillespie have the same problem. They are inconvenient to be carried and are difficult to be hidden in the summer. The users feel that they are connected to an external device and hate to be frequently asked, “What&#39;s that?” 
         [0003]     Micro-Electromechanical Systems (MEMS) is a rapidly growing field that is impacting the micro pumps used in the insulin pumps. However, this kind of pumps is too expensive to be disposable mainly because the coils are difficult to be built in the wafer and integrating the diaphragm and the valves into the micro pump are expensive. The company Debiotech developed the micro pump chip with piezoelectric actuator four years, ago. The products are still not available in the market. The systems developed recently, like those presented in the U.S. Pat. No. 6,827,559 by Peter, et al., have the same problem, too expensive to be disposable. For all these systems, the medication passes through the micro pumps. The medication may have very little residual staying in the devices for a long time if the devices are not disposable. The users will be skeptical to use them. Another research initiated in the California Institute of Technology developed the micro pump that boils a tiny bubble to drive the medication. However, the medication passes through the micro pump and is heated at the same time. This is a big concern and the users may hesitate to use the systems. The system is also too expensive to be disposable.  
         [0004]     In contrast to all the above approaches, my invention “Light, Thin, and Flexible Medication Infusion Apparatuses Attachable to User&#39;s Skin” with U.S. Pat. No. 6,699,234 presented conceptual models of thin and flexible infusion systems. The pump, the controller, the batteries, and the reservoir are thin and small and are laterally linked with flexible materials. So, the users can carry the pumps under their clothes or attach the pumps to their skin. Since the system is so close to the user&#39;s body and is flexible, the users will feel much more convenient and comfortable than using the conventional ones. Each pump may be expensive, but, the medication only passes through cheap and disposable tubes. Since the users will use the pumps for a long time, using these kinds of pumps will be much more economic than using the MEMS micro pumps. However, the infusion systems need thin and foldable pumps to drive the medication.  
         [0005]     The peristaltic pump has been widely used for medical purposes. There are mainly two kinds of such pump. The one that round rotator with rollers rotates and presses out the fluid from a section of tube is also caller roller pump. The other one is linear where the fluid is sequentially forced out from the input end to the output end of a section of pipe. Base on these concepts, the present invention presents the conceptual models of the fluid pump that are thin and foldable. It is ideal to be used in the medication infusion systems stated above. Since the hard compartments are small, the users will feel to be flexible.  
         [0006]     The first model is to install thin and small driving means in the rotator so that the whole pump is thin and small. The second model comprises a number of stages linked by flexible means so that each hard compartment is thin and small and the whole pump is thin and foldable. The user will feel like flexible. The fluid is drawn into the tube by the elasticity force of the tube and is pressed out of the tube by force applied to the tube. There can be more than one stage between the input and the output stages to improve the efficiency of the pump. For these two models, the pump may either pump the fluid directly or pump the air into a sealed fluid reservoir to force out the fluid indirectly. For the former, the fluid container may be flexible and the empty detection relies on detecting that the elastic tube cannot return to its original shape. For the latter, the empty detection relies on detecting that the elastic tube is over pumped. The user will appreciate the latter more because there are fewer parts to be disposed. Sidler presented to use the linear peristaltic pump for dosage control in the US patent application 2005019708. However, there are few fundamental differences. In Sidler&#39;s application, the pump is a one-piece hard compartment and the driving force to make the fluid flow into the pump is the pre-installed force in the fluid reservoir. Consequently, the empty detection relies on detecting the position of the plunger. The third model is to divide the pump into thin and small pieces and to laterally link them with flexible means so that the whole pump is thin and flexible.  
       OBJECTS AND ADVANTAGES  
       [0007]     My present invention presents conceptual models of thin and flexible fluid pump, using thin motors, electromagnetic drivers, or elastic devices. They are ideal to be used in the medication infusion systems. The users of the apparatuses using such pumps will feel convenient and comfortable to carry the apparatuses under their clothes or to attach the apparatuses to their skin. 
     
    
     DRAWING FIGURES  
       [0008]      FIG. 1 : The conceptual model of a thin fluid pump comprising a round rotator to press out the fluid in an elastic tube.  
         [0009]      FIG. 2 : The conceptual structure of the thin pump driven by rotary or rotary step motor.  
         [0010]     FIGS.  3 A and  3 B: The conceptual model of a thin pump driven by a linear motor or an electromagnetic driver.  
         [0011]      FIG. 4 : The structure of a conceptual model of thin pump that the round rotator is driven by the spiral spring.  
         [0012]      FIGS. 5A  to  5 E: The conceptual model of a thin pump that the elastic tube is pressed at different places in specific sequence to press out the fluid.  
         [0013]      FIG. 5F : The quantifier to press out precise amount of fluid.  
         [0014]      FIG. 5G : The device to eliminate the erroneous fluid made by input and output stages.  
         [0015]      FIG. 6 : The conceptual model of a thin pump comprising a number of pumping units.  
         [0016]      FIG. 7 : The conceptual model of a thin pumping unit driven by an elastic fluid bag.  
         [0017]      FIG. 8 : The conceptual model of a thin pumping unit driven by a spring.  
         [0018]      FIG. 9 : The conceptual model of a thin pumping unit driven by compressed air.  
         [0019]      FIG. 10 : The conceptual model of a thin pumping unit driven by a thin linear motor or electromagnetic driver. 
     
    
     SUMMARY  
       [0020]     This invention presents three conceptual models of fluid pump with similar innovation, to design thin and small compartments and laterally link all compartments with flexible means so that the whole fluid pump is thin and flexible. The first one uses the concept of spiral peristaltic pump. The rollers on the thin and round rotator of the thin spiral type of peristaltic pump roll over a section of elastic tube to press out the fluid in the tube. The rotator may be driven by a thin motor, electromagnetic driver, or spring. The second one uses the concept of linear peristaltic pump. The thin motors or electromagnetic drivers press different places of a section of elastic tube or its variation in special sequence to press out the fluid in the tube. Each motor or driver and the associated parts can be made to be a thin and small compartment. The third one uses the concept of distributed processor. It comprises a number of thin and small pumping units where each one uses the elastic force, compressed air, linear motor, or the electromagnetic device to press out limited amount of fluid in the container. Each pumping unit is designed to be a thin and small compartment. The number of pumping units is appropriate so that the user carries enough fluid to be convenient. For all models, the pump is laterally integrated by linking thin and small compartments with flexible means. The pump is as thin as the compartments and is flexible as the compartments are small and are linked with flexible cables, tubes, and other linking means. So, the user will feel comfortable to carry the pump under their clothes or to attach it to the skin.  
       DETAILED DESCRIPTION  
       [0021]     Three conceptual models of thin and foldable fluid pump are presented. Two of them are peristaltic type pumps that use the thin motors, the electromagnetic drivers, or the spring type of elastic devices to press out the fluid in the tube. The pump may draw in the fluid, like the medication, directed from the reservoir and press the fluid out of the pump. It also may pump the fluid, like the air, into a sealed fluid reservoir to press out the fluid. The first model is to use round driving device whose rollers press the fluid out of an elastic tube in one direction. The second model is that the elastic portions of a tube is pressed at different points with special sequence to press out the fluid. The third conceptual model of thin fluid pump is composed of a number of pump units. Each pump unit uses the thin motor, the electromagnetic driver, or the elastic device to press out the fluid in a thin fluid reservoir. The innovation relies on making them thin and foldable. Since the apparatus is to be carried under the user&#39;s clothes, a remote controller is used. To keep the figures neat, the controller, the batteries, and the cables may not be shown in the corresponding figures.  
         [0022]      FIG. 1  shows the first conceptual model of the pump. The round rotator  80  has a number of rollers  84  on its outer edge and can rotate. The pumping tube  86  is elastic. A roller  84  shuts off the pumping tube  86  when it rolls on the pumping tube  86 . There is at least one roller  84  to shut off the pumping tube  86  at any time. The tube support  90  is a hard device to help the rollers  84  to shut off the pumping tube  86  and is optional. A driving means drives the rotator  80  to rotate. The fluid in the pumping tube  86  is pressed along with the movement of the rollers  84 . Hence, the fluid is drawn from the input end and is pressed out from the output end of the pumping tube  86  through the fluid tubes  8 . Note that, when a roller  84  leaves the pumping tube  86 , the pumping tube  86  will return to its original shape. That will draw back the fluid that has been pressed out. So, the controller needs to know when a roller  84  leaves the pumping tube  86  and controls the rotator  80  to rotate to overcome this effect.  
         [0023]      FIG. 2  shows the conceptual structure of the driving means that the round rotator  80  is the thin and round actuator  80  of a thin rotary or rotary step motor. The stators are not shown in the figure. When the rotator, or the actuator,  80  is driven to rotate, the rollers  84  press out the fluid from the pumping tube  86 . For a step motor, the actuator  80  rotates fixed distance for each step or pulse. The controller counts the number of steps that the rotator  80  rotates and translates it to be the distance that the rollers  84  move. The cross section area of the pumping tube  86  times the distance that the rollers  84  move is the volume of the fluid pressed out. When enough fluid is pressed out, the controller stops the electrical current applied to the motor. For a rotary motor, the mechanism to detect the distance that the actuator moves is simple. Contacting points are installed on the actuator and the stators or the substrate. Detecting which contacting point on the actuator contacts which contacting point on the stators, the controller will know how long the actuator moves.  
         [0024]      FIGS. 3A and 3B  show the conceptual model of another driving means where the round rotator  80  is driven by a linear motor or a linear electromagnetic driver  42 . The round rotator  80  has a ring of rotating gears  82  on its inner side. Inside the round rotator  80  and the ring of rotating gears  82 , there is a linear motor or linear electromagnetic driver  42  that drives its actuator  44  to move up and down. Each of the two ends of the actuator  44  has a pushing gear  88 . As shown in  FIG. 3A , the tip portion of the tilting face of the lower pushing gear  88  encounters the tip portion of the tilting face of the rotating gear  82  right below the actuator  44  when the actuator  44  moves down. Hence, the round rotator  80  is pushed to rotate clockwise when the actuator  44  continues to move down. As shown in  FIG. 3B , the tip portion of the tilting face of the upper pushing gear  88  encounters the tip portion of the tilting face of the rotating gear  82  right above the actuator  44  when the actuator  44  moves up. Hence, the round rotator  80  is pushed to rotate clockwise when the actuator  44  continues to move up. The smallest movement of the rollers is one pushing by the actuator  44 . That is a step. The controller is easy to control the volume of the fluid to be pumped.  
         [0025]      FIG. 4  shows the structure of another conceptual model of the driving means that the round rotator  80  is driven by the thin spiral spring  30 . The outer end of the spiral spring  30  is connected to the round rotator  80  and the inner end is connected to the fastener  92 . The fastener  92  can fasten the spring  30  in one direction only. So, the fastened spring  30  drives the round rotator  80  to rotate accordingly. The mechanism to detect the distance that the round rotator  80  moves is similar with that explained above. Contacting points are installed on the round rotator  80  and the substrate. Detecting which contacting point on the round rotator  80  contacts which contacting point on the substrate, the controller will know how long the round rotator  80  rotates. That is translated to be the volume of the fluid delivered. The unit controller  24  is a linear motor or linear electromagnetic driver  42  that can drive its actuator  44 . The actuator  44  is driven to stick into the round rotator  80  to stop the round rotator  80  normally. When the round rotator  80  needs to rotate, the actuator  44  is pulled to let the round rotator  80  rotate. When enough fluid is delivered, the actuator  44  is controlled to stick into the round rotator  80  to stop the round rotator  80  again.  
         [0026]      FIGS. 5A  to  5 E show the conceptual model of a thin pump that the elastic tube is pressed at different places in specific sequence to press out the fluid. There are three or more stages: an input stage, one or more dosage stages, and an output stage. Each stage has a linear motor or a linear electromagnetic driver that can drive its actuator back and forth. In the example shown in the figures, there are four dosage stages. The input stage  42 I, the dosage stages  42 A,  42 B,  42 C, and  42 D, and the output stage  42 O can drive the input actuator  44 I, the dosage actuators  44 A,  44 B,  44 C, and  44 D, and the output actuator  44 O, respectively.  FIG. 5A  shows the state that the pump is not pumping where the output stage shuts off the pumping tube  86  normally. The left end of the elastic pumping tube  86  is connected to the fluid source and the right end is connected to the destination. The input actuator  44 I and the dosage actuators  44 A,  44 B,  44 C, and  44 D do not press the pumping tube  86 . The output actuator  44 O is connected to the spring  30  to press and to shut off the pumping tube  86 . When the pump begins to pump the fluid, the input actuator  44 I is driven to press and to shut off the pumping tube  86  as  FIG. 5B  shows. Then, the output actuator  44 O is driven to leave and to open the pumping tube  86  as  FIG. 5C  shows. Then, the dosage actuators  44 A,  44 B,  44 C, and  44 D are selectively driven to press the pumping tube  86 . In this example, the dosage actuators  44 A and  44 D are selected as  FIG. 5D  shows. Then, the output stage  42 O is deactivated. The spring  30  will drive the output actuator  44 O to press and to shut off the pumping tube  86  as  FIG. 5E  shows. Then, the input and all dosage stages  42 I,  42 A,  42 B,  42 C, and  42 D are deactivated. The pumping tube  86  is elastic and, hence, will push all the input actuator  44 I and the dosage actuators  44 A,  44 B,  44 C, and  44 D back as  FIG. 5A  shows. Or, the input actuator  44 I and the dosage actuators  44 A,  44 B,  44 C, and  44 D are driven by the stages to leave and to open the pumping tube  86 . The elasticity of the pumping tube  86  will draw the fluid from the fluid source into the pumping tube  86 . This cycle presses out some fluid in the pumping tube  86 . Each of the dosage actuators  44 A,  44 B,  44 C, and  44 D may press out different volume of fluid. Preferably, the volume pressed out by the dosage actuators  44 A,  44 B,  44 C, and  44 D is 1, 2, 4, and 8 units, respectively. So, the volume pressed out in one cycle can be any units from 1 to 15. In the example shown in  FIG. 5D , 9 units of fluid are pressed out.  
         [0027]     The volume of the fluid pressed out by a dosage actuator needs to be precise. The quantifier  62  shown in  FIG. 5F  solves the problem. It is a piece of hard tube  67  whose outer diameter is the same as the inner diameter of the pumping tube  86  and is installed inside of the pumping tube  86 . It has one dosage concavity associated with each dosage actuator. The volume of each dosage concavity is the volume of the fluid to be pressed out by the associated actuator. The tip of each dosage actuator matches the contour of the associated dosage concavity. So, when a dosage actuator is driven to press the pumping tube  86 , the dosage actuator fits into the associated dosage concavity. Hence, exact amount of the fluid is pressed out. In the example, there are four dosage concavities  66 A,  66 B,  66 C, and  66 D associated with the dosage actuators  44 A,  44 B,  44 C, and  44 D, respectively. The material of the pumping tube is chosen to be that, when there is not any pressure on it, it always returns to the original shape. So, when a dosage actuator releases the quantifier, exact amount of the fluid is drawn in. An alternative is that each dosage concavity of the quantifier is covered and laminated with an elastic membrane. Then, the fluid tubes are connected to the two ends of the quantifier. It works the same way.  
         [0028]     When the output stage releases the elastic pumping tube  86 , the fluid in the output tube is drawn back to the output stage. The same amount of the fluid will be pressed out when the output stage shuts off the pumping tube  86 . However, since the tube is elastic, these two amounts may have very small difference. The solution is similar with the above and is shown in  FIG. 5G . The hard tube  67  has a concavity  67  and is installed in the pumping tube  86 . The tip of the output actuator  44 O matches the contour of the concavity  67 . When the output stage shuts off the pumping tube  86 , the actuator  44 O presses the pumping tube  86  fits in the concavity  67  so that the pumping tube  86  is shut off. Since the contour of the concavity  67  and the tip of the output actuator  44 O are hard and permanent, the amount of the fluid drawn in and pressed out the output stage will be the same. The input stage has similar problem and the solution is the same.  
         [0029]     Any number of stages may be installed to be a hard compartment. The quantifiers of different hard compartments are linked with flexible tubes, flexible cables, and other flexible linking means. For the best flexibility, each stage is installed to be a hard compartment and all stages are linked with flexible tubes, flexible cables, and other flexible linking means. So, the resulting fluid pump is flexible.  
         [0030]     Alternatively, the input stage may shuts off the pumping tube when the pump is not in operation. For either model, the springs  30  of the input or the output stage may be eliminated. Then, current needs to be applied to the input or the output stage to shut off the elastic pumping tube  86 . Or, the input or the output stage is latched after the elastic pumping tube  86  is shut off.  
         [0031]     For the above two models, the fluid pump either draws the fluid directly from the reservoir and presses out the drawn fluid or pumps the air into the sealed fluid reservoir to press out the fluid indirectly. For the former, the empty detection is to detect that the pump is unable to draw the fluid. In the other words, this is to detect that the pumping tube cannot return to the original shape. An easy way to do so is to add a section of empty detection tube having a portion that is significantly more flexible than the pumping tube between the reservoir and the pump. So, when the reservoir is empty and the pumping tube returns to the original shape, the elastic portion of the empty detection tube will be concave. That can drive a switch. The controller will know that the reservoir is empty when the switch changes state. For the latter, the empty detection is to detect that the air is over pumped into the reservoir. The solution is similar with the above. The empty detection tube has a portion that is significantly more flexible than the pumping tube. So, when the reservoir is empty and the pump pumps the air into the reservoir, the elastic portion of the empty detection tube will be convex. That can drive a switch, too. The controller will know that the reservoir is empty when the switch changes status.  
         [0032]      FIG. 6  shows another conceptual model of the fluid pump that comprises a number of pumping units  47 . A pumping unit  47  further comprises a unit controller  55 , a pumping means, and a fluid bag  70  to hold the fluid. Since the fluid pump is carried under the user&#39;s clothes, the pumping unit  47  must be small. However, it may be too small to carry enough fluid in the fluid bag  70  because the pumping means also takes space but the total fluid in all fluid bags  70  is enough. The system controller  50  controls that the pumping units  47  take turns to deliver the fluid. The unit controller  55  controls the pumping means to press out the fluid in the fluid bag  70 . The output fluid tubes  8  of the pumping units  47  are connected to an adapter  79 . The output fluid tube  8  of the adapter  79  is connected to the destination. Alternatively, the fluid bags  70  are linked in cascade where every two consecutive fluid bags  70  are linked with a flexible fluid tube  8 . All hard compartments, the pumping units  47 , the system controller  50 , and the batteries with holders  90 , are linked with flexible fluid tubes  8 , cables  95 , and pad type linking means  96  so that the system is thin and foldable.  
         [0033]      FIG. 7  shows a conceptual model of pumping unit  47  that uses elastic fluid bag to press out the fluid in the bag. The unit case  10  is small and thin enough to be comfortably carried under the user&#39;s clothes or attached to the user&#39;s skin. Inside the unit case  10 , there is a piston  20 , a movement transferor  25 , and an elastic fluid bag  70 . The movement transferor  25  can be any combination of movement transferors, chains, strings, rods, or any kind of similar material as long as it can transfer the movement between the piston  20  and the unit controller  55 . The fluid bag  70  connects to the piston  20  and the case front  65 . When it is filled with fluid, the tension of the fluid bag  70  is strong enough to press out the fluid. It also pulls the piston  20  toward the case front  65 . The tension also keeps the fluid bag  70  straight so that the variation of the cross section area of the fluid bag  70  is negligible. The inner cross section area of the fluid bag  70  times the distance that the piston  20  moves is the amount of fluid that is pressed out. The piston  20  can be a little bit smaller than the inner cross section of the unit case  10  so that the friction between the unit case  10  and the piston  20  is minimized. The movement transferor  25  connects to the piston  20 . So, when the fluid bag  70  pulls the piston  20 , the movement transferor  25  transfers the movement of the piston  20  to the unit controller  55  that determines the movement of the piston  20 . The unit controller  55  can hold the movement transferor  25  so that the fluid stops flowing out of the fluid bag  70  and can also release the movement transferor  25  so that the fluid bag  70  pulls the piston  20  to press out the fluid. When the fluid pressed out is enough, the unit controller  55  holds the movement transferor  25  to stop the fluid flowing out.  
         [0034]      FIG. 8  shows a conceptual model of the pumping unit  47  using an elastic device  30 , like the spring, to press out the fluid in the fluid bag  70 . The tightened or straightened elastic device  30  either drives the piston  20  directly or drives the movement transferors  25  to drive the piston  20  indirectly to press out the fluid. The rest is similar with that shown in  FIG. 7 .  
         [0035]      FIG. 9  shows a conceptual model of the pumping unit  47  using the compressed-air bag  38  to press out the fluid in the fluid bag  70 . The compressed-air bag  38  is connected to the air pump  24  via the air pipe  72 . Then, the air pump  24  pumps the air into the compressed-air bags  38 . When enough air is pumped into the compressed-air bag  38 , the air pump  24  and the air pipe  12  are detached. The compressed air in the compressed-air bags  38  will press out the fluid if the unit controller  55  releases the movement transferors  25 . The rest is similar with the above. Alternatively, the air pump  24  may pump the air into air reservoirs originally and the air reservoirs are linked to the air bags  38 . The figure is not shown.  
         [0036]      FIG. 10  shows a conceptual model of the pumping unit  47  that the unit controller  55  comprises a thin linear step motor whose actuator  44  either drives the piston  20  directly or drives the movement transferors  25  to drive the piston  20  indirectly to press out the fluid. Each step that the actuator  44  advances will press out fixed amount of the fluid. The rest is similar with that shown in  FIG. 7 .  
       CONCLUSION  
       [0037]     Accordingly, the readers can see that each of the three models of the fluid pump is composed of small and thin compartments that are laterally linked with flexible means. Hence, each pump is as thin as the compartments and is foldable. The present invention also showed that all such compartments can be thin. Therefore, the fluid pump is thin. The apparatuses using such fluid pump are thin, too. Since each hard compartment is small, the user will feel like flexible. They are ideal to be carried under the user&#39;s clothes or be attached to the user&#39;s skin. The user will feel much more comfortable to use them.  
         [0038]     Although the description above contains many specifications, these should not be constructed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.