Patent Publication Number: US-2019167126-A1

Title: Blood pressure monitor

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is a divisional of U.S. patent application Ser. No. 14/993,378 filed on Jan. 12, 2016 which claims the benefit under 35 USC 119(a) of Korean Patent Application No. 10-2015-0120722, filed on Aug. 27, 2015 in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. 
    
    
     BACKGROUND 
     1. Field 
     The following description relates to a blood pressure monitor including a manually operable pressurizer. 
     2. Description of Related Art 
     A sphygmomanometer, or a blood pressure monitor referred to herein, may be an apparatus configured to measure a blood pressure of a user. The blood pressure monitor may apply pressure to a body of a user and measure blood pressure of the user based on values measured while the pressure is being released. Blood pressure monitors typically include a motor to apply the pressure to the body of the user. The blood pressure monitor may transfer or apply, through operation of the motor, pressure to a cuff configured to measure the blood pressure. In addition, the blood pressure monitor may adjust the speed at which the pressure transferred to the cuff is then released. 
     However, this motor may be large in volume and consume a great amount of power, and thus using such a motor in the blood pressure monitor may not be suitable to reduce the size of the blood pressure monitor. A person&#39;s blood pressure may be used to diagnose a disease associated with blood pressure when measured frequently and in various environments. 
     SUMMARY 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is the Summary intended to be used as an aid in determining the scope of the claimed subject matter. 
     One or more embodiments include a blood pressure monitor, including a cuff configured to apply a pressure to a target portion of a body of a user, a pressurizer including a rotator, the pressurizer configured to supply a fluid to the cuff, to cause the cuff to apply the pressure, through rotation of the rotator caused by an external rotational force applied to the blood pressure monitor to rotate the rotator, a depressurizer configured to reduce the applied pressure applied by the cuff to the target portion, and a sensor configured to measure a pressure of the target portion. 
     The pressurizer may include a tube connected to the cuff, and the rotator may be configured to supply the fluid to the cuff by rotating in a state in which at least a portion of the tube is blocked. 
     The pressurizer may include a string configured to apply the rotational force to rotate the rotator upon an external pulling of the string by the user. 
     The pressurizer may be a manually operable peristaltic pump operated by the rotation of the rotator. 
     The pressurizer may include a ratchet configured to selectively maintain a rotation direction to be constant. 
     The depressurizer may include a rotary damper configured to reduce the pressure applied by the cuff to the target portion at a constant rate by controlling a rotating of the rotator in a direction opposite to the rotation direction of the rotator caused by the external force, when the external force is ceased. 
     The monitor may further include a tube configured to supply the fluid to the cuff, and the depressurizer may include a valve configured to maintain a speed at which the fluid is discharged from the cuff to be constant when the external rotational force is ceased. 
     The valve may include a ring configured to obstruct a flow of the fluid, and a support configured to support the ring based on the flow of the fluid and in which a taper, inclined in a direction in which the fluid flows, is formed. 
     The monitor may further include a controller configured to generate, with respect to a determined change in a blood flow of the target portion, a first feedback signal based on a determination of when pressure should be increased by application of the external force and a second feedback signal based on a determination of when the applied pressure should be decreased. 
     One or more embodiments provide a blood pressure monitor, including a band configured to cover a target portion of a body of a user and configured to apply pressure to the target portion through movement of a constrictor device of the band, a pressure adjuster configured to cause the band to adjust the movement of the constrictor device to control the applying of the pressure to the target portion, and a sensor configured to measure a pressure of the target portion. 
     The pressure adjuster may include a support axis winding at least a portion of the band to cause the constrictor device to constrict, and a ratchet configured to selectively maintain a rotation direction of the support axis in a first direction by an external force applied to the blood pressure monitor. 
     The pressure adjuster may include a rotary damper configured to maintain a rotation speed of the support axis in a second direction at a constant speed when the application of the external force ceases and the ratchet does not maintain the rotation direction of the support axis in the first direction. 
     The constrictor device may be a string within the band, and the pressure adjuster may include a support axis configured to wind at least a portion of the string to cause the band to constrict in response to an external force applied to the blood pressure monitor, and a ratchet configured to selectively maintain a rotation direction of the support axis in a first direction that winds the string around the support axis. 
     The pressure adjuster may include a rotary damper configured to maintain a rotation speed of the support axis in a second direction at a constant speed when the application of the external force ceases and the ratchet does not maintain the rotation direction of the support axis in the first direction. 
     The monitor may further include a controller configured to generate, with respect to a determined change in a blood flow of the target portion, a first feedback signal based on a determination of when pressure should be increased by application of an external force to the pressure adjuster and a second feedback signal based on a determination of when the applied pressure should be decreased. 
     One or more embodiments provide a blood pressure monitor, including a support system including at least two support elements to at least partially surround a target portion of a body of a user, a pressure adjuster configured to adjust a pressure to be applied to the target portion by the support system by selective control of movement directions of at least one of the two support elements relative to each other, to apply pressure to the target portion by the at least one of the two support elements by being caused, by application of at least one external force to the blood pressure monitor, to move in a respective first movement direction, and a sensor configured to measure a pressure of the target portion. 
     The pressure adjuster may include a ratchet configured to perform selective control of the at least one of the two support elements to move in the first direction so that an angle between the at least two support elements decreases through the application of the external force. 
     The pressure adjuster may include at least one hinge damper configured to adjust a speed at which at least one of the two support elements releases to increase an angle between the two support elements at a constant speed to decrease the applied pressure. 
     The monitor may further include a controller configured to generate, with respect to a determined change in a blood flow of the target portion, a first feedback signal based on a determination of when pressure should be increased by the application of the external force and a second feedback signal based on a determination of when the applied pressure should be decreased. 
     One or more embodiments provide a blood pressure monitoring method including generating a feedback signal to a user to indicate when a user should cease manual application of an external force to a blood pressure monitor of one or more embodiments discussed herein, measuring pressure of a corresponding target portion of the user based on a determined change in blood flow, and outputting a calculated blood pressure of the user based on measured pressure. 
     Other features and aspects will be apparent from the following detailed description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating a blood pressure monitor including a non-powered pressurizer, in accordance with one or more embodiments. 
         FIG. 2  is a diagram illustrating a blood pressure monitor configured to adjust pressure applied to a target portion using a fluid, in accordance with one or more embodiments. 
         FIG. 3  is a diagram illustrating a blood pressure monitor cuff, in accordance with one or more embodiments. 
         FIG. 4  is a diagram illustrating a blood pressure monitor with a string for rotation of a rotator, in accordance with one or more embodiments. 
         FIG. 5  is a diagram illustrating a blood pressure monitor with a rotary damper, in accordance with one or more embodiments. 
         FIG. 6  is a diagram illustrating a valve configured to maintain a depressurization speed, in accordance with one or more embodiments. 
         FIG. 7  is a diagram illustrating a blood pressure monitor configured to adjust pressure applied to a target portion through a contraction of a band, in accordance one or more embodiments. 
         FIG. 8  is a diagram illustrating a blood pressure monitor configured to adjust pressure applied to a target portion through a tightening of a band, in accordance one or more embodiments. 
         FIG. 9  is a diagram illustrating a blood pressure monitor configured to adjust pressure applied to a target portion through a tightening of a support, in accordance with one or more embodiments. 
         FIGS. 10A and 10B  illustrate examples of states in which a blood pressure monitor may be worn, in accordance with one or more embodiments. 
         FIG. 11  is a graph illustrating an operation of a controller of a blood pressure monitor, in accordance with one or more embodiments. 
         FIG. 12  is a flowchart illustrating controller operations in a blood pressure monitoring method, in accordance with one or more embodiments. 
     
    
    
     Throughout the drawings and the detailed description, unless otherwise described or provided, the same drawing reference numerals will be understood to refer to the same elements, features, and structures. The drawings may not be to scale, and the relative size, proportions, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience. 
     DETAILED DESCRIPTION 
     The following detailed description is provided to assist the reader in gaining a comprehensive understanding of the methods, apparatuses, and/or systems described herein. However, after an understanding of the present disclosure, various changes, modifications, and equivalents of the methods, apparatuses, and/or systems described herein will be apparent to one of ordinary skill in the art. The sequences of operations described herein are merely examples, and are not limited to those set forth herein, but may be changed as will be apparent, after an understanding of the present disclosure, to one of ordinary skill in the art, with the exception of operations necessarily occurring in a certain order. Also, descriptions of functions and constructions that may be understood, after an understanding of differing aspects of the present disclosure, may be omitted in some descriptions for increased clarity and conciseness. 
     Various alterations and modifications may be made to embodiments, some of which will be illustrated in detail in the drawings and detailed description. However, it should be understood that these embodiments are not construed as limited to the disclosure and illustrated forms and should be understood to include all changes, equivalents, and alternatives within the idea and the technical scope of this disclosure. 
     Terms used herein are to merely explain specific embodiments, thus it is not meant to be limiting. A singular expression includes a plural expression except when two expressions are contextually different from each other. For example, as used herein, the singular forms “a”, “an”, and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Herein, a term “include” or “have” are also intended to indicate that characteristics, figures, operations, components, or elements disclosed on the specification or combinations thereof exist. The term “include” or “have” should be understood so as not to pre-exclude existence of one or more other characteristics, figures, operations, components, elements or combinations thereof or additional possibility. In addition, though terms such as first, second, A, B, (a), (b), and the like may be used herein to describe components, unless indicated otherwise, these terminologies are not used to define an essence, order, or sequence of a corresponding component but used merely to distinguish the corresponding component from other component(s). 
     Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which respective embodiments belong. It will be further understood that terms, such as those defined in commonly-used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     When describing the examples with reference to the accompanying drawings, like reference numerals refer to like constituent elements and a repeated description related thereto will be omitted. When it is determined that a detailed description related to an understood or previously discussed operation or configuration may make a purpose of a subsequent embodiment unnecessarily ambiguous in describing the embodiment, such a detailed description will be omitted. 
     As only an example, in the field of wearable devices such as smart watches and smartwear, the size and power consumption of a blood pressure monitor may be an important issue to be considered. Accordingly, in one or more embodiments, a blood pressure monitor with a reduced size and reduced power requirements may be provided. For example, the blood pressure monitor may be configured so that pressurization may be implemented with a non-powered pressurizer that operates based on manual pressure inducements with a reduced size for compact use, such as with smart watch or smart wear embodiments, as well as with other embodiments. 
       FIG. 1  is a diagram illustrating a blood pressure monitor  100  including a non-powered pressurizer, in accordance with one or more embodiments. Referring to  FIG. 1 , the blood pressure monitor  100  includes a pressurizer  110 , a depressurizer  120 , a cuff  130 , a sensor  140 , and a controller  150 , for example. The blood pressure monitor  100  measures a blood pressure of a user from a target portion of a body of the user. The target portion may include, for example, a wrist and an upper arm of the user. The target portion may be, for example, an entire wrist and an entire upper arm of the user. The target portion may be, for example, a portion of the wrist and a portion of the upper arm of the user. The target portion may be, for example, a portion of the wrist and the upper arm in which an artery passes. For example, the target portion may be a portion in which a radial artery and brachial artery of the user pass. 
     The pressurizer  110  is configured to increase a pressure that is applied to the target portion. The pressurizer  110  increases the pressure for the target portion by an external force. The external force may be generated through manipulation by the user. Depending on embodiment, the pressurizer  110  may increase the pressure for the target portion through various mechanisms based on an external force. In a non-limiting example, the pressurizer  110  may increase the pressure for the target portion by supplying a fluid to the cuff  130  through rotation by an external force. In another non-limiting example, the pressurizer  110  may increase the pressure for the target portion through a contraction of a band covering the target portion. In still another non-limiting example, the pressurizer  110  may increase the pressure for the target portion through a tightening of the band covering the target portion. In yet another non-limiting example, the pressurizer  110  may increase the pressure for the target portion through a tightening of a support of a support system configured to support the target portion. Further descriptions of such examples will be described in greater detail further below. 
     The depressurizer  120  is configured to reduce the pressure that is applied to the target portion. The depressurizer  120  may start a depressurizing of the target portion by an external force. After the depressurizing of the target portion starts by the external force, a depressurization state may be maintained by a structure of the depressurizer  120 . To measure an accurate blood pressure, maintaining a depressurization speed may be desired. The depressurization speed indicates a rate at which a pressure is reduced per hour, for example. The depressurizer  120  may include various structures to maintain the depressurization speed. In an example, the depressurizer  120  may include various dampers. For example, the depressurizer  120  may include at least one of a rotary damper and a hinge damper. In another example, the depressurizer  120  may include various valves. For example, the depressurizer  120  may include a constant flow valve. Such example structures will be described in greater detail further below, noting that alternative embodiments are also available. 
     In a case that the pressure of the target portion increases and decreases through any one structure, the pressurizer  110  and the depressurizer  120  may be referred to as a pressure adjuster. 
     The cuff  130  applies a pressure to the target portion. The cuff  130  may include, or caused to include, various fluids to allow the cuff  130  to be closely attached to the target portion. A fluid may include various forms of gas and liquid. For example, the fluid may include air and a gel. For example, a degree of contact between the cuff  130  and the target portion may be adjusted based on an amount of the fluid included in the cuff  130 . In one or more embodiments, the cuff  130  may be provided as a flexible material to be in a closer contact with the target portion. 
     The sensor  140  measures a pressure of the target portion. In addition, the sensor  140  may measure a blood flow of the target portion. The sensor  140  may be located around the target portion. The sensor  140  may include a pressure sensor configured to measure the pressure of the target portion and an optical sensor configured to measure the blood flow of the target portion, for example. 
     The controller  150  may generate measurement data based on an output data, readings, or signals from the sensor  140 . The measurement data may include a blood pressure in a contraction period, a mean blood pressure, and a blood pressure in a relaxation period, for example. A process of calculating the blood pressure in the contraction period, the mean blood pressure, and the blood pressure in the relaxation period will be described in greater detail further below. 
     In addition, the controller  150  may generate diagnosis data based on the measurement data. For example, the controller  150  may generate the diagnosis data by comparing the measurement data to reference data. The diagnosis data may include data or conclusions regarding a health condition of the user associated with a blood pressure. For example, the controller  150  may determine whether the blood pressure of the user is normal, high, or low by comparing the measurement data to the reference data. The reference data may be determined based on physical information of the user. For example, the reference data may be determined to be data corresponding to the physical information of the user among various sets of data corresponding to various sets of physical information. The controller  150  may include an input user interface, for example, where such reference information or other information is entered for consideration by the controller  150 . 
     The controller  150  may be configured to transmit at least one of the measurement data and the diagnosis data to an external device, for example. In an embodiment, the external device may include a personal device of the user and a medical server, such as in a blood monitoring system embodiment. In an embodiment, the controller  150  may be configured to transmit the measurement data and the diagnosis data to the personal device of the user to allow the user to verify the measurement data and the diagnosis data through the personal device of the user. Also, the controller  150  may be configured to transmit the measurement data to the medical server. In an embodiment, a doctor may input the diagnosis data to the medical server based on the measurement data, and the controller  150  may be configured to then receive the diagnosis data from the medical server. 
     The controller  150  may be configured to generate a feedback signal, e.g., associated with a desired manipulation by the user. For example, the feedback signal may include a first feedback signal to request the user for pressurization and a second feedback signal to request the user for depressurization. A process of generating the feedback signal will be described in greater detail further below. 
     Here, the controller  150  includes hardware that may be configured to implement one or more, or all, of the operations described herein, depending on embodiment. As only an example, the hardware may be a special purpose processor or computer, e.g., configured to implement one or more methods or operations described herein and/or configured to implement or operate based on processor readable code that implements such methods or operations. 
     Although not illustrated in  FIG. 1 , depending on embodiment, the blood pressure monitor  100  includes an output device component. The output device component is a hardware component that may include at least one of a display device, a speaker, and a vibrator, as only examples. The controller  150  may output the feedback signal to the user through the output device component. In addition, the controller  150  may output the measurement data and the diagnosis data to the user through the output device component. In addition, depending on embodiment, the controller  150  or the blood pressure monitor  100  includes one or more input device components, as hardware that are configured to request, accept, or receive input from a user interface and/or signals of sensors of the blood pressure monitor  100  or external sensors of the blood pressure monitor, such as for measuring pressure or blood flow, as discussed in greater detail further below. 
     Still further, although not illustrated in  FIG. 1 , in one or more embodiments, the blood pressure monitor  100  includes a communication hardware module. For example, the controller  150  exchanges the data with the personal device of the user and the medical server through the communication module. 
       FIG. 2  is a diagram illustrating a blood pressure monitor configured to adjust pressure applied to a target portion using a fluid, in accordance with one or more embodiments. Referring to  FIG. 2 , the blood pressure monitor may include a body  210 , a bezel  220 , a band  230 , a tube  240 , and a rotator  250 , for example. The blood pressure monitor may also include the cuff  130 , the sensor  140 , and the controller  150 , for example, described with reference to  FIG. 1 . 
     In one or more embodiments, the body  210  is fixed to the band  230 , for example. The body  210  includes at least a portion of the tube  240  and the rotator  250 . The bezel  220  rotates on the body  210  through an external force. The bezel  220  rotates the rotator  250  based on the external force. 
     The tube  240  and the rotator  250  are collectively referred to as a pressurizer. The tube  240  and the rotator  250  supply a fluid to a cuff through rotation by an external force. For example, the tube  240  and the rotator  250  may be a peristaltic pump, and the tube  240  and the rotator  250  may make up a manually operable peristaltic pump, as only an example of such a manually operable peristaltic pump. 
     In one or more embodiments, one end of the tube  240  is connected to the cuff, and another end of the tube  240  is connected to a fluid bag to supply the fluid or is exposed in air. For example, the other end of the tube  240  may be disconnected. A hole may be present around the other end of the tube  240 . The tube  240  is connected to the cuff through the band  230 . The fluid included in the tube  240  flows through the rotation of the rotator  250 . The tube  240  supplies the fluid to the cuff through the rotation of the rotator  250 . 
     The rotator  250  may include a plurality of projections. The projections may form a plurality of spaces in the tube  240 . Thus, the rotator  250  may block at least a portion of the tube  240 . Here, to “block” and to perform a “blocking” as referred to herein may be construed as indicating a state that may induce a flow of the fluid rather than indicating closing or sealing. The rotator  250  supplies the fluid to the cuff while rotating in a state in which the at least a portion of the tube  240  is blocked. The rotator  250  rotates in a rotation direction as illustrated in  FIG. 2 . In one or more embodiments, the rotator  250  includes a ratchet. The rotation direction of the rotator  250  may be maintained by application of the ratchet. A discharge of the fluid supplied to the cuff may be prevented through the ratchet. A lock of the ratchet may be released by an external force, for example. When the lock of the ratchet is released, depressurization of the target portion may be initiated. For example, when the lock of the ratchet is released, the rotator  250  may be connected to a rotary damper. 
     Thus, in one or more embodiments, the band  230  fixes the blood pressure monitor to a body of a user. The band  230  fixes the cuff. The cuff is fixed to the target portion through the band  230 . An example of the cuff will be described in greater detail with reference to  FIG. 3 . 
     Here, though a blood pressure monitor configured to adjust pressure applied to a target portion using a fluid has been discussed above with reference to elements of  FIG. 2 , embodiments are not limited thereto and alternative manually operable fluid based pressure inducing elements may be used for applying pressure to the target portion. 
       FIG. 3  is a diagram illustrating a blood pressure monitor cuff  330 , in accordance with one or more embodiments. Referring to  FIG. 3 , a blood pressure monitor includes a body  310 , a band  320 , and the cuff  330 . The blood pressure monitor may also include the bezel  220 , the tube  240 , and the rotator  250 , such as described with reference to  FIG. 2 . For example, the body  310  may include the tube  240  and the rotator  250 . 
     The cuff  330  may be provided in various sizes based on the target portion. The cuff  330  may be provided in a size to apply a pressure to a portion around a radial artery. For example, the cuff  330  may be provided in a size corresponding to a portion of the band  320 . Also, the cuff  330  may be provided in a size to apply a pressure to an entire portion of a wrist. For example, the cuff  330  may be provided in a size corresponding to an entire portion of the band  320 . 
     The cuff  330  includes a fluid to be closely attached to the target portion. A volume of the cuff  330  may vary with the fluid. The cuff  330  is connected to a tube, for example, the tube  240 . An amount of the fluid included in the cuff  330  is adjusted through the tube. For example, the fluid may be supplied to the cuff  330  through the tube, and discharged from the cuff  330  through the tube. The cuff  330  is expanded by the supply of the fluid, and contracted by the discharge of the fluid. That is, the cuff  330  may increase a pressure of the target portion by the supply of the fluid, and decrease the pressure of the target portion by the discharge of the fluid. 
     Referring back to  FIG. 2 , the rotator  250  rotates by an external force. The external force may include manipulation by the user. In an example, the rotator  250  may rotate through a string. Such a string will be further described with reference to  FIG. 4 , as only an example. 
       FIG. 4  is a diagram illustrating a blood pressure monitor with a string  610  for rotation of a rotator, in accordance with one or more embodiments. Referring to  FIG. 4 , a blood pressure monitor includes the string  610  and a bezel  620 . The string  610  is connected to the bezel  620 . The string  610  may be connected to the bezel  620  or the rotator  250 , such as described with reference to  FIG. 2 . In an embodiment, when the string  610  is pulled in a movement direction as illustrated in  FIG. 4 , the bezel  620  or the rotator  250  may rotate clockwise, for example. Thus, a user may increase a pressure of a target portion using the string  610  without directly manipulating the bezel  620 . 
     Referring back to  FIG. 2 , for example, the rotator  250  supplies a fluid to a cuff while rotating in a rotation direction as illustrated in  FIG. 2 . In addition, the rotator  250  may discharge the fluid supplied to the cuff while rotating in a direction opposite to the rotation direction. In response to the discharge of the fluid, a pressure of the target portion may decrease. To measure an accurate blood pressure, a depressurization speed may need to be maintained. The depressurization speed may be maintained using various structures. The depressurization speed may be maintained using various dampers. For example, the depressurization speed may be maintained using a rotary damper. Alternatively, the depressurization speed may be maintained using a valve. Such a rotary damper and valve will be further respectively described with reference to  FIGS. 5 and 6 , as only examples. 
     Here, though a blood pressure monitor configured to adjust pressure applied to a target portion using a string has been discussed above with reference to elements of  FIG. 4 , embodiments are not limited thereto and alternative manual devices other than such a string may be used for externally rotating the bezel or rotator. 
       FIG. 5  is a diagram illustrating a blood pressure monitor with a rotary damper, in accordance with one or more embodiments. Referring to  FIG. 5 , a blood pressure monitor includes a body  410 , a support  420 , and a rotator  430 , for example. The blood pressure monitor may also include the bezel  220 , the tube  240 , and the rotator  250 , such as described with reference to  FIG. 2 . For example, the body  410  may include at least a portion of the tube  240  and the rotator  250 . The support  420  and the rotator  430  may be collectively referred to as a depressurizer. 
     The body  410  includes the support  420  and the rotator  430 . In one or more embodiments, the support  420  is fixed to the body  410 . The rotator  430  rotates on the support  420  in a rotation direction as illustrated in  FIG. 5 . A rotation speed of the rotator  430  may be maintained to be constant through friction with the support  420 . For example, the rotation speed of the rotator  430  may be maintained to be constant by a lubricant between the rotator  430  and the support  420  or a spring connecting the rotator  430  and the support  420 . 
     The rotator  430  may be connected to the rotator  250 , such as illustrated in  FIG. 2 . For example, when a lock of a ratchet is released, the rotator  430  may be connected to the rotator  250  through an axis of the support  420 . The rotator  430  and the rotator  250  may share the axis and be located on opposite sides of the support  420 . The rotator  430  may maintain a rotation speed of the rotator  250 . For example, the rotator  430  may maintain the depressurizing rotation speed of the rotator  250  to be constant through friction with the support  420 . In response to the rotation speed of the rotator  250  being maintained, a depressurization speed of a target portion may be maintained. Thus, accuracy in measuring a blood pressure may be improved. 
       FIG. 6  is a diagram illustrating a valve configured to maintain a depressurization speed, in accordance with one or more embodiments. Referring to  FIG. 6 , a tube  710  may include a ring  720  and a support  730 , for example. The tube  710  may be a portion of the tube  240 , such as described with reference to  FIG. 2 . 
     The ring  720  may obstruct a flow of a fluid through a hole smaller than the tube  710 . The ring  720  may move in a direction in which the fluid flows based on the flow of the fluid. The ring  720  may be closely attached to the support  730  based on a speed of the fluid. The support  730  may include a taper inclined in the direction in which the fluid flows. When the ring  720  is attached closer to the support  730 , the hole of the ring  720  may be narrowed. Also, when the ring  720  is attached closer to the support  730 , the speed of the fluid may decrease. Thus, the speed of the fluid may be maintained to be constant through the ring  720  and the support  730 , and thus accuracy in measuring a blood pressure may be improved. 
       FIG. 7  is a diagram illustrating a blood pressure monitor configured to adjust pressure applied to a target portion through a contraction of a band  530 , in accordance with one or more embodiments. Referring to  FIG. 7 , the blood pressure monitor may include a rotator  510 , a body  520 , the band  530 , and a string  540 , for example. The blood pressure monitor may also include the cuff  130 , the sensor  140 , and the controller  150 , such as described with reference to  FIG. 1 . 
     The string  540  may be wound around a support axis fixed to the rotator  510  when the rotator  510  rotates in a rotation direction as illustrated in  FIG. 7 . At least a portion of the band  530  may include a cuff, for example, the cuff  130 . When the string  540  is wound around the support axis, the band  530  may be contracted. In response to the band  530  being contracted, the pressure of the target portion may increase. When the string  540  is released from the support axis, the band  530  may be relaxed. In response to the band  530  being relaxed, the pressure of the target portion may decrease. The body  520  may include a ratchet configured to adjust a rotation direction of the support axis to allow the support axis to rotate in a constant direction. 
     A relaxation speed of the band  530  may be adjusted by at least one damper described in the foregoing. For example, the rotation speed of the support axis may be adjusted by a rotary damper. As described in the foregoing, the rotation speed of the support axis may be maintained to be constant through friction between a rotator of the rotary damper and a support of the rotary damper or by a spring connecting the rotator of the rotary damper and the support of the rotary damper. The string  540 , the support axis, and the ratchet may be collectively referred to a pressure adjuster. 
     Here, though a blood pressure monitor configured to adjust pressure applied to a target portion using elements for contracting a band have been discussed above with reference to elements of  FIG. 7 , embodiments are not limited thereto and alternative elements for adjusting the pressure may be used. 
       FIG. 8  is a diagram illustrating a blood pressure monitor configured to adjust pressure applied to a target portion through a tightening of a band  930 , in accordance with one or more embodiments. Referring to  FIG. 8 , the blood pressure monitor may include a body  910 , a pressure adjuster  920 , and the band  930 , for example. The blood pressure monitor may also include the cuff  130 , the sensor  140 , and the controller  150 , such as described with reference to  FIG. 1 . 
     In one or more embodiments, the body  910  includes the pressure adjuster  920 . The pressure adjuster  920  may include a support axis covering at least a portion of the band  930 . In addition, the pressure adjuster  920  may include a ratchet configured to adjust a rotation direction of the support axis to allow the support axis to rotate in a constant direction through an external force. In response to a movement of the band  930  in an arrow-indicating direction as illustrated in  FIG. 8 , a pressure to be applied to the target portion may be adjusted. For example, when the support axis rotates in a first direction, the pressure of the target portion may increase. When the support axis rotates in a second direction, the pressure of the target portion may decrease. A user may increase the pressure of the target portion by pulling the band  930 , and decrease the pressure of the target portion by releasing the band  930 . 
     A depressurization speed may be determined based on a speed at which the band  930  is released. The speed at which the band  930  is released may be adjusted based on the user manually controlled rotation speed of the support axis. For example, the rotation speed of the support axis in the second direction may be maintained to be constant through a rotary damper. As described in the foregoing, the rotation speed of the support axis may be maintained to be constant through friction between a rotator of the rotary damper and a support of the rotary damper or by a spring connecting the rotator of the rotary damper and the support of the rotary damper, as only examples. 
     Here, though a blood pressure monitor configured to adjust pressure applied to a target portion using elements for tightening a band have been discussed above with reference to elements of  FIG. 8 , embodiments are not limited thereto and alternative elements for tightening the band may be used. 
       FIG. 9  is a diagram illustrating a blood pressure monitor configured to adjust pressure applied to a target portion through a tightening of a support, in accordance with one or more embodiments. Referring to  FIG. 9 , the blood pressure monitor may include a first support  810 , a second support  820 , and a pressure adjuster  830 , for example. The blood pressure monitor may also include the cuff  130 , the sensor  140 , and the controller  150 , such as described with reference to  FIG. 1 . 
     The first support  810  and the second support  820  may cover the target portion. Depending on embodiment, the first support  810  and the second support  820  may cover the entirety of the target portion, such as completely surrounding a wrist or arm body portion, or may cover only a portion of the target portion. The first support  810  and the second support  820  cover the target portion by being tightened or closed in an arrow-indicating direction as illustrated in  FIG. 9 . Thus, an angle between the first support  810  and the second support  820  may be adjusted through an external force. 
     The pressure adjuster  830  may include a ratchet, for example, configured to adjust a direction in which the first support  810  and the second support  820  are tightened to allow the angle between the first support  810  and the second support  820  to decrease. For example, the ratchet may maintain a direction in which the first support  810  and the second support  820  move to decrease the angle between the first support  810  and the second support  820  to reach a limit angle. In response to the decrease in the angle between the first support  810  and the second support  820 , the pressure of the target portion may increase. 
     When the ratchet is released, the angle between the first support  810  and the second support  820  may increase. In response to the increase in the angle between the first support  810  and the second support  820 , the pressure of the target portion may decrease. A depressurization speed may be determined based on a speed at which the angle between the first support  810  and the second support  820  increases. The pressure adjuster  830  includes hinge dampers, for example, a first hinge damper  831  and a second hinge damper  832 , configured to adjust the speed at which the supports  810  and  820  are released to allow the angle between the first support  810  and the second support  820  to increase at a constant speed. The first hinge damper  831  may be fixed to the first support  810 , and the second hinge damper  832  may be fixed to the second support  820 , for example. When the depressurization speed is maintained by the hinge dampers  831  and  832 , accuracy in measuring a blood pressure may be improved. 
     Here, though a blood pressure monitor configured to adjust pressure applied to a target portion using a support system that can be tightened have been discussed above with reference to elements of  FIG. 9 , embodiments are not limited thereto and alternative support system support elements that can be tightened, clamped, or closed relative to each other, for example, may be used. 
       FIGS. 10A and 10B  illustrate examples of states in which a blood pressure monitor may be worn, in accordance with one or more embodiments. Referring to  FIG. 10A , a blood pressure monitor  1011  is worn around an upper arm of a user. The blood pressure monitor  1011  includes an expandable band to be worn on various portions of a body of the user. Referring to  FIG. 10B , a blood pressure monitor  1022  is included in a smartwear device  1021 . A user may measure a blood pressure through the blood pressure monitor  1022  while the user is wearing the smartwear device  1021 . 
       FIG. 11  is a graph illustrating an operation of a controller of a blood pressure monitor, in accordance with one or more embodiments. 
     In the graph of  FIG. 11 , a pressure measured in a first section  1110 , a second section  1120 , and a third section  1130 , and an actual blood pressure of a user are illustrated. The first section  1110  is a section in which an increase in a pressure by an external force is manually made by the user, the second section  1120  is a section in which a decrease in the pressure is made, and the third section  1130  is a section in which measurement data and diagnosis data are generated based on measured pressures. 
     In the first section  1110 , a first feedback signal may be output to request the user to apply pressure. The user may create and increase pressure applied to a target portion through a blood pressure monitor based on the first feedback signal. For example, the user may rotate the bezel  220  illustrated in  FIG. 2 . In the second section  1120 , a second feedback signal may be output to request the user to reduce the applied pressure. The user may decrease the pressure of the target portion through the blood pressure monitor based on the second feedback signal. For example, the user may release a lock of a ratchet by touching the body  210  illustrated in  FIG. 2 . The first feedback signal and the second feedback signal may be output through an output device component of the blood pressure monitor, such as discussed above, or an external device. 
     In the third section  1130 , the measurement data and the diagnosis data are generated based on the measured pressure. The measurement data and the diagnosis data may be generated by the controller  150 , such as described with reference to  FIG. 1 . In response to the pressure of the target portion being lowered, a pulsation may be detected in the target portion. The controller determines a pressure at which the pulsation is detected to be a blood pressure in a contraction period. For example, the controller determines a pressure at which an amplitude of the pulsation is at a maximum level to be a mean blood pressure. In addition, the controller determines a pressure at which the pulsation decreases to a minimum level to be a blood pressure in a relaxation period, for example. 
       FIG. 12  is a flowchart illustrating controller operations in a blood pressure monitoring method, in accordance with one or more embodiments. Referring to  FIG. 12 , in operation  1210 , the controller generates a first feedback signal. The first feedback signal is a signal to request a user to apply pressure. The controller outputs the first feedback signal to the user. In operation  1220 , the controller monitors a change in a blood flow of a target portion. In operation  1230 , the controller generates a second feedback signal. The second feedback signal is a signal to request the user to reduce the pressure. The controller may generate the second feedback signal after verifying whether the blood flow of the target portion is suspended in response to the pressure being applied to the target portion. The controller outputs the second feedback signal to the user. In operation  1240 , the controller generates measurement data based on measured pressures of the target portion. The measurement data may include, for example, measurements of blood pressures during a contraction period, a determined mean blood pressure, and measurements of blood pressure during a relaxation period. The controller generates diagnosis data based on the measurement data. In addition, in one or more embodiments, the controller transmits the measurement data and the diagnosis data to an external device, or outputs the data to the user through an output device component, such as discussed above. 
     The apparatuses, units, modules, devices, and other components illustrated in any of the blood pressure monitors of  FIGS. 1 through 10B  that perform the operations of  FIGS. 11-12 , for example, are implemented by hardware components. As only an example, the controllers of any of the blood pressure monitors of  FIGS. 1-10B  include such hardware components. Hardware components may include, as only examples, resistors, transistors, capacitors, inductors, power supplies, controllers, frequency generators, operational amplifiers, power amplifiers, low-pass filters, high-pass filters, band-pass filters, analog-to-digital converters, digital-to-analog converters, and processing device(s), processor(s), and/or computer(s), as only examples. A processing device, processor, or computer may be implemented by one or more processing elements, such as an array of logic gates, a controller and an arithmetic logic unit, a digital signal processor, a microcomputer, a programmable logic controller, a field-programmable gate array, a programmable logic array, a microprocessor, or any other device or combination of devices known to one of ordinary skill in the art that is capable of responding to and executing instructions in a defined manner to achieve a desired result. In one example, a processing device, processor, or computer includes, or is connected to, one or more memories storing instructions or software that are executed by the processing device, processor, or computer and that may control the processing device, processor, or computer to implement one or more methods described herein. Hardware components implemented by a processing device, processor, or computer, such as of the controller of any of the blood pressure monitors of FIGS.  FIGS. 1-10B , as only an example, may execute instructions or software, such as an operating system (OS) and one or more software applications that run on the OS, to perform or control one or more of the operations described herein with respect to  FIGS. 11-12 , for example. The hardware components also access, manipulate, process, create, and/or store data in response to execution of the instructions or software. For simplicity, the singular term “processing device”, “processor”, or “computer” may be used in the description of the examples described herein, but in other examples multiple processing devices, processors, or computers are used, or a processing device, processor, or computer includes multiple processing elements, or multiple types of processing elements, or both. In one example, a hardware component includes multiple processors, and in another example, a hardware component includes a processor and a controller. A hardware component has any one or more of different processing configurations, examples of which include a single processor, independent processors, parallel processors, remote processing environments, single-instruction single-data (SISD) multiprocessing, single-instruction multiple-data (SIMD) multiprocessing, multiple-instruction single-data (MISD) multiprocessing, and multiple-instruction multiple-data (MIMD) multiprocessing, as only examples. 
     The methods illustrated in  FIGS. 11-12  that perform or control the operations described herein may be performed or controlled by a processing device, processor, or a computer as described above executing instructions or software to perform one or more of the operations described herein. 
     Instructions or software to control a processing device, processor, or computer to implement the hardware components and perform the methods as described above may be written as computer programs, code segments, instructions or any combination thereof, for individually or collectively instructing or configuring the processing device, processor, or computer to operate as a machine or special-purpose computer to perform the operations performed by the hardware components and the methods as described above. In one example, the instructions or software include machine code that is directly executed by the processing device, processor, or computer, such as machine code produced by a compiler. In another example, the instructions or software include higher-level code that is executed by the processing device, processor, or computer using an interpreter. Based on the disclosure herein, and after an understanding of the same, programmers of ordinary skill in the art may readily write the instructions or software based on the block diagrams and the flow charts illustrated in the drawings and the corresponding descriptions in the specification, which disclose such method operations and which may be performed or implemented by any of the above described hardware components, for example. 
     The instructions or software to control a processing device, processor, or computer to implement the hardware components, such as discussed in any of  FIGS. 1-10B , and perform or control the implementation of the methods as described above in  FIGS. 11-12 , and any associated data, data files, and data structures, are recorded, stored, or fixed in or on one or more non-transitory computer-readable storage media. Examples of a non-transitory computer-readable storage medium include read-only memory (ROM), random-access memory (RAM), dynamic random-access memory (D-RAM), static random-access memory (S-DRAM), flash memory, CD-ROMs, CD-Rs, CD+Rs, CD-RWs, CD+RWs, DVD-ROMs, DVD-Rs, DVD+Rs, DVD-RWs, DVD+RWs, DVD-RAMs, BD-ROMs, BD-Rs, BD-R LTHs, BD-REs, magnetic tapes, floppy disks, magneto-optical data storage devices, optical data storage devices, hard disks, solid-state disks, and any device known to one of ordinary skill in the art that is capable of storing the instructions or software and any associated data, data files, and data structures in a non-transitory manner and providing the instructions or software and any associated data, data files, and data structures to a processing device, processor, or computer so that the processing device, processor, or computer can execute the instructions. In one example, the instructions or software and any associated data, data files, and data structures are distributed over network-coupled computer systems so that the instructions and software and any associated data, data files, and data structures are stored, accessed, and executed in a distributed fashion by the processing device, processor, or computer. 
     As a non-exhaustive example only, and in addition to the above explanation of potential hardware implementations of an electronic device either as the blood pressure monitor, or electronic device that includes the blood pressure monitor, or electronic device that at least includes the controller of the blood pressure monitor may also be a mobile device, such as a cellular phone, a smart phone, a wearable smart bio-signal device, a portable personal computer (PC) (such as a laptop, a notebook, a subnotebook, a netbook, or an ultra-mobile PC (UMPC), a tablet PC (tablet), a phablet, a personal digital assistant (PDA), a digital camera, a portable game console, an MP3 player, a portable/personal multimedia player (PMP), a handheld e-book, a global positioning system (GPS) navigation device, or a sensor, or a stationary device, such as a desktop PC, a television or display, a DVD player, a Blu-ray player, a set-top box, or a home appliance, an Internet of Things device, or any other mobile or stationary device, e.g., capable of wireless or network communication, for example, and capable of receiving or sensing/capturing the body data and biometric data, for example, and capable of determining a biometric state based on the received/sensed information, as well capable of informing a user of the determined biometric state, depending on embodiment. 
     While this disclosure includes specific examples, it will be apparent to one of ordinary skill in the art that various changes in form and details may be made in these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered in a descriptive sense only, and not for purposes of limitation. Descriptions of features or aspects in each example are to be considered as being applicable to similar features or aspects in other examples. Suitable results may be achieved if the described techniques are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined in a different manner, and/or replaced or supplemented by other components or their equivalents. Therefore, the scope of the disclosure is not limited by the detailed description, but further supported by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are to be construed as being included in the disclosure.