Patent Publication Number: US-2021170130-A1

Title: Mask outer frame unit, mask unit, band-including mask unit and mask outer frame

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority from Japanese Patent Application No. 2019-221084 filed on Dec. 6, 2019, the entire content of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     The presently disclosed subject matter relates to a mask outer frame unit, a mask unit, a band-including mask unit, and a mask outer frame. 
     BACKGROUND ART 
     When artificial respiration is performed by non-invasive positive pressure ventilation, continuous positive airway pressure, or the like, a mask is attached to the face of a patient. On this occasion, it is desirable that the mask is firmly fixed to the face of the patient. However, since the size of the face of one patient varies from the size of the face of another patient, it is necessary to, for example, adjust the position of a portion of the mask in contact with the forehead of the patient in order to attach the mask to a suitable position. Patent document JP-T-2008-526395 discloses a mask assembly provided with a head frontal region support body having a slide bar which can slide. 
     When the artificial respiration is performed by use of the non-invasive positive pressure ventilation, the continuous positive airway pressure, or the like, strong compression pressure is applied to a portion of the patient&#39;s face in contact with the mask. In addition, the mask can be attached to the patient for a relatively long time. 
     Accordingly, there is a fear that a feeling of discomfort is caused to the patient due to the strong compression pressure applied to the same place of the patient wearing the mask for a long time. In this respect, the mask assembly according to Patent document JP-T-2008-526395 still has room for improvement. 
     SUMMARY 
     An object of the presently disclosed subject matter is to provide a mask outer frame unit, a mask unit, a band-including mask unit, and a mask outer frame each of which can lighten a feeling of discomfort caused to a patient with a simple configuration. 
     The mask outer frame unit according to an aspect in order to achieve the aforementioned object is a mask outer frame unit that can include: 
     a mask outer frame that can be mounted on a mask attached to a face of a patient; and 
     a pad that can abut against the face of the patient; wherein: 
     the mask outer frame has a forehead contact portion that is disposed so as to make the pad abut against a forehead of the patient; and 
     the forehead contact portion is provided with an adjustment portion to which the pad can be attached removably and that can adjust at least one of an angle of the pad with respect to the forehead contact portion and a position of the pad with respect to the forehead contact portion. 
     The mask unit according to an aspect in order to achieve the aforementioned object can include: 
     the mask outer frame unit; and 
     a mask that can be attached to the face of the patient. 
     The band-including mask unit according to an aspect in order to achieve the aforementioned object can include: 
     the mask unit; and 
     bands that can be placed into the mask unit and that can be attached to the patient. 
     The mask outer frame according to an aspect in order to achieve the aforementioned object is a mask outer frame that can be mounted on a mask attached to a face of a patient, wherein: 
     the mask outer frame includes a forehead contact portion that is disposed so as to make a pad abuttable against the face of the patient abut against a forehead of the patient; 
     an adjustment portion for removably attaching the pad thereto is provided in the forehead contact portion; and 
     the adjustment portion can adjust at least one of an angle of the pad with respect to the forehead contact portion and a position of the pad with respect to the forehead contact portion. 
     According to the aforementioned configuration, the adjustment portion to which the pad can be removably attached and that can adjust at least one of an angle of the pad with respect to the forehead contact portion and a position of the pad with respect to the forehead contact portion is provided in the forehead contact portion. Accordingly, it is possible to easily change the angle of the pad with respect to the forehead contact portion or the position of the pad with respect to the forehead contact portion without changing the position of the mask or the outer frame. 
     Thus, according to the aforementioned configuration, it is possible to lighten a feeling of discomfort caused to the patient with a simple configuration. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a view illustrating external appearance of a mask unit according to an embodiment. 
         FIG. 2  is a view of a section taken along a line A-A of  FIG. 1 . 
         FIGS. 3A and 3B  are a bottom view of a pad to be attached to a forehead contact portion, and a view illustrating a rear face of the pad to be attached to the forehead contact portion. 
         FIG. 4  is a view illustrating a use example of a band-including mask unit. 
         FIG. 5  is a view illustrating a forehead contact portion according to a first modification. 
         FIG. 6  is a view illustrating a forehead contact portion according to a second modification. 
         FIG. 7  is a view illustrating a forehead contact portion according to a third modification. 
     
    
    
     DESCRIPTION OF EMBODIMENT 
     An embodiment will be described below in detail by way of example with reference to the accompanying drawings. Incidentally, “up”, “down”, “left”, “right”, “front” and “rear” used in the specification and the drawings of the presently disclosed subject matter denote directions displayed for convenience of explanation, and are not intended to be limited to the illustrated directions. 
       FIG. 1  is a perspective view of a mask unit  1  according to an embodiment. The mask unit  1  can be used when, for example, non-invasive positive pressure ventilation (NPPV) or continuous positive airway pressure (CPAP) is used in treatment of chronic respiratory failure or artificial respiration. 
     As illustrated in  FIG. 1 , the mask unit  1  may include a mask  2 , and a mask outer frame unit  3  (hereinafter also referred to as outer frame unit  3  simply). 
     The mask  2  may include a mask body portion  21 , a hose connection portion  22 , and a cushion member  23 . 
     The mask body portion  21  is formed into a shape which covers the nose and the mouth of a patient while forming a space for the patient to breathe through his/her nose and mouth. The mask body portion  21  has at least a portion transparent or semitransparent so that the nose and the mouth of the patient can be visually recognized through the transparent or semitransparent portion. The mask body portion  21  is preferably formed out of a hard resin material. Such a resin material is, for example, polycarbonate. 
     The hose connection portion  22  is formed into a tabular shape. The hose connection portion  22  is provided in a lower portion of the mask body portion  21  so as to make the space of the mask body portion  21  communication with an external space. The hose connection portion  22  is formed out of a hard resin material such as polycarbonate. 
     The cushion member  23  is provided along, of the mask body portion  21 , a circumferential edge portion making contact with the face of the patient. The cushion member  23  is formed out of a soft resin material so that the cushion member  23  can be flexibly deformed to be kept airtight against the face of the patient. 
     The outer frame unit  3  may include a mask outer frame  31  (hereinafter also referred to outer frame  31  simply), and a pad  32 . 
     The outer frame  31  may include a mounting portion  311  and a forehead contact portion  312 . The outer frame  31  is formed out of a hard resin material such as polycarbonate. 
     The mounting portion  311  is formed into an inverted Y-shape in front view to extend upward from an upper portion of the mask body portion  21  and extend from the upper portion of the mask body portion  21  toward the left and right of a lower portion of the mask portion  21 . The mounting portion  311  is mounted on the upper portion of the mask body portion  21  and the left and right places of the lower portion of the mask body portion  21 . The mounting portion  311  may include first band attachment portions  313  at its lower left end portion and its lower right end portion respectively. Each of the first band attachment portions  313  has an I-shaped frame structure through which a band  41  (see  FIG. 4 ) can be inserted in a front/rear direction to be then folded back to the left or right. 
     As illustrated in  FIG. 1 , the forehead contact portion  312  is disposed so as to make the pad  32  abut against the forehead of the patient. The forehead contact portion  312  is a plate-like portion formed continuously to an upper end of the mounting portion  311 . In the present example, the external shape of the forehead contact portion  312  in front view is an approximately quadrilateral shape whose corner portions have been chamfered. Incidentally, the forehead contact portion  312  may be configured to be curved in accordance with the shape of the forehead. 
     Second band attachment portions  315  are provided respectively at the centers of left and right end portions of the forehead contact portion  312 . Each of the second band attachment portions  315  has a hook-shaped lock structure through which a band  41  (see  FIG. 4 ) can be inserted in the front/rear direction to be then folded back to the left or right. 
     An adjustment portion  314  to which the pad  32  can be removably attached and which can adjust at least one of an angle (posture) and a position of the pad  32  with respect to the forehead contact portion  312  is provided in the forehead contact portion  312 . 
     The adjustment portion  314  in the present example may include a first attachment portion  316 A, a second attachment portion  316 B and a third attachment portion  316 C which are attachment portions for attaching the pad  32  thereto. 
     Each of the first attachment portion  316 A, the second attachment portion  316 B and the third attachment portion  316 C may include a pair of left and right circular through holes (an example of attachment regions or engagement recesses). The first attachment portion  316 A, the second attachment portion  316 B and the third attachment portion  316 C are disposed side by side in an up/down direction in the forehead contact portion  312 . The first attachment portion  316 A provided in an upper part may include a first right through hole  317 A and a first left through hole  317 B. The second attachment portion  316 B provided in an intermediate part may include a second right through hole  317 C and a second left through hole  317 D. The third attachment portion  136 C provided in a lower part may include a third right through hole  317 E and a third left through hole  317 F. The corresponding ones of the through holes  317 A to  317 F provided in each of the mounting portions  316 A to  316 C can be engaged with engagement protrusions  322  of the pad  32  which will be described later. 
       FIG. 2  is a view of a section taken along a line A-A in  FIG. 1  to illustrate only the forehead contact portion  312 . 
     As illustrated in  FIG. 2 , each of the first left through hole  317 B, the second left through hole  317 D and the third left through hole  317 F is formed so as to make its diameter larger toward the rear. The rear of the forehead contact portion  312  is a side on which a body portion of the pad  32  attached to one of the first attachment portion  316 A, the second attachment portion  316 B and the third attachment portion  316 C is disposed. In each of the first left through hole  317 B, the second left through hole  317 D and the third left through hole  317 F, a diameter d 2  of a rear end is larger than a diameter d 1  of a front end. The first right through hole  317 A, the second right through hole  317 C and the third right through hole  317 E also have a sectional structure similar to or the same as that of the first left through hole  317 B, the second left through hole  317 D and the third left through hole  317 F. 
     Next, the pad  32  will be described with reference to  FIGS. 3A and 3B .  FIG. 3A  is a bottom view of the pad  32  to be attached to the forehead contact portion  312 .  FIG. 3B  is a view illustrating a rear face of the pad  32  to be attached to the forehead contact portion  312 . The pad  32  is a buffer material disposed between the forehead contact portion  312  and the forehead of the patient. The pad  32  is, for example, made of a soft resin and can be elastically deformed. As illustrated in  FIG. 3A , the pad  32  may include a pad body portion  321  and engagement protrusions  322 . The pad body portion  321  may include a plurality of cavities  321   a  to  321   f  internally. Due to the cavities  321   a  to  321   f  provided in the pad body portion  321 , the pad body portion  321  can expand and contract in the front/rear direction easily. That is, the pad body portion  321  has a cushion function. Incidentally, the pad body portion  321  according to the present embodiment has six cavities  321   a  to  321   f . However, the number of the cavities is not limited thereto as long as the pad body portion  321  can exert the cushion function. In addition, the pad body portion  321  does not have to be configured to have the cavities. 
     As illustrated in  FIG. 3B , the rear face of the pad body portion  321  has an approximately rectangular shape. However, the shape of the rear face of the pad body portion  321  may be any other shape such as a square shape or a circular shape. 
     Next, the engagement protrusions  322  will be described with reference to  FIG. 3A . The engagement protrusions  322  are regions serving for engaging the pad  32  with one of the attachment portions  316 A to  316 C. The engagement protrusions  322  are provided on the left and the right to be paired. Each of the engagement protrusions  322  may include a pedestal portion  323 , a cylindrical column portion  324 , and a truncated cone portion  325 . The pedestal portion  323  is a mountain type. The pedestal portion  323  is formed continuously to the pad body portion  321 . 
     The cylindrical column portion  324  is disposed between the pedestal portion  323  and the truncated cone portion  325 . The cylindrical column portion  324  is formed continuously to the pedestal portion  323  and the truncated cone portion  325 . A diameter d 3  of the cylindrical column portion  324  is substantially equal to a diameter d 4  of a front end of the pedestal portion  323 . The diameter d 3  of the cylindrical column portion  324  is smaller than a diameter d 5  of a rear end of the truncated cone portion  325 . 
     The diameter d 3  of the cylindrical column portion  324  is smaller than the diameter d 2  on the rear side of each through hole  317 A to  317 F (see  FIG. 2 ). The diameter d 3  of the cylindrical column portion  324  is substantially equal to the diameter d 1  on the front side of the through hole  317 A to  317 F (see  FIG. 2 ). The diameter d 5  of the rear end of the truncated cone portion  325  is larger than the aforementioned diameter d 1 . In addition, a length LI of the cylindrical column portion  324  in the front/rear direction is substantially equal to a thickness TI of the forehead contact portion  312  in the front/rear direction (see  FIG. 2 ). 
     To attach the pad  32  to one of the first attachment portion  316 A, the second attachment portion  316 B and the third attachment portion  316 C, a user such as a medical worker brings the truncated cone portions  325  of the engagement protrusions  322  into contact with ones of the through holes  317 A to  371 F and presses the truncated cone portions  325  into the ones of the through holes  317 A to  371 F so as to elastically deform the truncated cone portions  325 . As a result, each of the diameters of the truncated cone portions  325  becomes smaller than the diameter d 1  on the front side of each through hole  317 A to  317 F. In the state where the truncated cone portions  325  have been elastically deformed, the user such as the medical worker presses the truncated cone portions  325  forward. Thus, the truncated cone portions  325  are inserted into, of the through holes  317 A to  317 F, the through holes into which the user desires to insert the pad  32 . That is, the engagement protrusions  322  are inserted into, of the through holes  317 A to  317 F, the through holes into which the user desires to insert the pad  32 . When the truncated cone portions  325  are inserted into the through holes of the through holes  317 A to  317 F, and moved forward from the through holes into which the truncated cone portions  325  have been inserted, the truncated cone portions  325  are restored to their original states. Since the diameter d 5  of each of the rear ends of the truncated cone portions  325  is larger than the diameter d 1  of each of the through holes  317 A to  317 F, the truncated cone portions  325  are engaged with the through holes of the through holes  317 A to  317 F. As a result, the truncated cone portions  325  are restricted from moving rearward so that the pad  32  can be restrained from coming off rearward from the forehead contact portion  312 . 
     Next, a band-including mask unit  10  will be described with reference to  FIG. 4 .  FIG. 4  is a view illustrating a use example of the band-including mask unit  10 . The band-including mask unit  10  may include the mask unit  1  and bands  41 . In the band-including mask unit  10 , the bands  41  are inserted through the first band attachment portions  313  and the second band attachment portions  315  respectively. Of each of the bands  41 , a portion passing through the cheek of a patient is inserted through one of the first band attachment portions  313  from the rear toward the front to be then folded back to the left or the right. An end portion  41   a  of the band  41  is pasted to a portion of the band  41  positioned near the cheek of the patient, for example, by use of a hook-and-loop fastener. Of each of the bands  41 , a portion passing through the head of the patient is inserted through one of the first band attachment portions  315  from the rear toward the front to be then folded back to the left or the right. An end portion  41   b  of the band  41  is pasted to a portion of the band  41  positioned near the head of the patient, for example, by use of a hook-and-loop fastener. The bands  41  can fix the band-including mask unit  10  to the cheek and the head of the patient. The bands  41  are formed out of a material having elasticity. For example, silicone rubber or the like can be used as such a material. 
     Here, a use example of the band-including mask unit  10  will be described. First, a user such as a medical worker attaches the pad  32  to one of the first attachment portion  316 A, the second attachment portion  316 B and the third attachment portion  316 C. In the example illustrated in  FIG. 4 , the pad  32  is attached to the third attachment portion  316 C. 
     Next, the user attaches the bands  41  to the patient so as to surround the cheek and the head of the patient. Thus, in a state where the pad  32  has abutted against the forehead of the patient, the band-including mask unit  10  is fixed to the patient. When the band-including mask unit  10  is attached to the patient, for example, artificial respiration is started. 
     When the artificial respiration is performed by non-invasive positive pressure ventilation, continuous positive airway pressure, or the like, the mask is attached to the face of the patient. On this occasion, the mask is firmly fixed to the face of the patient. However, in order to reduce leak between the face of the patient and the mask, strong compression pressure is applied to the face of the patient. The mask is attached to the patient for a relatively long time. Accordingly, when the artificial respiration is performed by use of a background-art mask, there is a fear that a feeling of discomfort is caused to the patient due to the strong compression pressure applied to the same place for a long time. 
     In order to solve such a problem, the mask unit  1  is used as follows. When a predetermined time elapses after the artificial respiration is started, the user first removes the bands  41  fixed to the head of the patient from the head of the patient, and then moves the forehead contact portion  312  forward to cancel the abutment state between the pad  32  and the forehead of the patient in order to change the attachment position of the pad  32 . For example, to change the attachment position of the pad  32  from the third attachment portion  316 C to the second attachment portion  316 B, the user first applies rearward force to the pad  32 . As a result, the truncated cone portions  325  are elastically deformed by the through holes  317 E and  317 F respectively so that the diameters of the truncated cone portions  325  can be smaller. The user pulls the pad  32  rearward while elastically deforming the truncated cone portions  325 . Accordingly, the user removes the engagement protrusions  322  from the third right through hole  317 E and the third left through hole  317 F. Thus, the pad  32  is detached from the third attachment portion  316 C. The user then inserts the engagement protrusions  322  into the second right through hole  317 C and the second left through hole  317 D while elastically deforming the truncated cone portions  325  of the engagement protrusions  322 . As a result, the user attaches the pad  32  to the second attachment portion  316 B. 
     According to the aforementioned configuration, it is possible to easily change the position where the compression pressure is applied to the patient by only changing not the position of the mask  2  or the outer frame  31  but the attachment position of the pad  32  (the attachment position of the pad  32  to the forehead contact portion  312 ). Accordingly, a feeling of discomfort caused to the patient can be lightened with a simple configuration. 
     In addition, according to the aforementioned configuration, the adjustment portion  314  includes the first attachment portion  316 A, the second attachment portion  316 B and the third attachment portion  316 C which are the attachment portions for attaching the pad  32  thereto. Accordingly, the position where the pad  32  is in contact with the forehead of the patient can be changed while the position of the forehead contact portion  312  having the adjustment portion  314  is maintained as it is. 
     In addition, according to the aforementioned configuration, each of the first attachment portion  316 A, the second attachment portion  316 B and the third attachment portion  316 C includes a pair of left and right circular through holes. The first attachment portion  316 A, the second attachment portion  316 B and the third attachment portion  316 C are disposed side by side in the up/down direction in the forehead contact portion  312 . Accordingly, the position where the pad  32  is in contact with the forehead of the patient can be changed in the up/down direction while the position of the forehead contact portion  312  having the adjustment portion  314  is maintained as it is. 
     In addition, according to the aforementioned configuration, the engagement protrusions  322  are provided in the pad  32 . The through holes functioning as engagement recesses are provided in each of the attachment portions  316 A to  316 C. The pad  32  is softer than the attachment portion  316 A to  316 C. Accordingly, the pad  32  can secure an elastic deformation amount for sufficiently exerting the cushion function required of the pad  32  without excessively increasing the thickness of the pad  32 , in comparison with a case where the engagement protrusions  322  are provided in each of the attachment portions  316 A to  316 C, and the through holes functioning as engagement recesses are provided in the pad  32 . 
     In addition, according to the aforementioned configuration, each of the first attachment portion  316 A, the second attachment portion  316 B and the third attachment portion  316 C includes a pair of left and right circular through holes. Accordingly, the engagement protrusions  322  of the pad  32  are easily engaged with any one of the attachment portions  316 A to  316 C. 
     In addition, according to the aforementioned configuration, each of the through holes  317 A to  317 F in the adjustment portion  314  is formed so that the diameter of the through hole  317 A to  317 F is larger toward the rear of the forehead contact portion  312 , i.e. toward the side on which the body portion of the pad  32  attached to one of the first attachment portion  316 A, the second attachment portion  316 B and the third attachment portion  316 C is disposed. Accordingly, the pad  32  can be prevented from easily coming off from the corresponding ones of the through holes  317 A to  317 F. 
     Modifications each having a different configuration of a forehead contact portion from the configuration of the forehead contact portion  312  in the aforementioned embodiment will be described below. 
     (First Modification) 
       FIG. 5  is a view illustrating a forehead contact portion  412  according to a first modification. The forehead contact portion  412  is different from the forehead contact portion  312  at a point that an adjustment portion  414  different in configuration from the adjustment portion  314  is provided. 
     The adjustment portion  414  may include a first attachment portion  416 A, a second attachment portion  416 B, and a third attachment portion  416 C. 
     The adjustment portion  414  is different in configuration from the adjustment portion  314  at a point that the first attachment portion  416 A and the second attachment portion  416 B are formed continuously to each other, and the second attachment portion  416 B and the third attachment portion  416 C are formed continuously to each other. 
     Each of a first right through hole  417 A and a first left through hole  417 B of the first attachment portion  416 A may include a portion which extends downward so as to be smaller in width in the left/right direction to be connected to the second attachment portion  416 B. Each of a second right through hole  417 C and a second left through hole  417 D of the second attachment portion  416 B may include a portion which extends upward so as to be smaller in width in the left/right direction to be connected to the first attachment portion  416 A. Each of the second right through hole  417 C and the second left through hole  417 D of the second attachment portion  416 B may include a portion which extends downward so as to be smaller in width in the left/right direction to be connected to the third attachment portion  416 C. Each of a third right through hole  417 E and a third left through hole  417 F of the third attachment portion  416 C may include a portion which extends upward so as to be smaller in width in the left/right direction to be connected to the second attachment portion  416 B. 
     Widths W 1  of the portions where the first attachment portion  416 A and the second attachment portion  416 B are connected to each other, and the portions where the second attachment portion  416 B and the third attachment portion  416 C are connected to each other are smaller than the diameter d 3  of the cylindrical column portion  324  of the pad  32 . 
     To change the attachment position of the pad  32  on the forehead contact portion  412  according to the first modification, a user can move the pad  32  among the attachment portions  416 A to  416 C by use of the portions where the first attachment portion  416 A and the second attachment portion  416 B are connected to each other or the portions where the second attachment portion  416 B and the third attachment portion  416 C are connected to each other. That is, the user can adjust the position of the pad  32  with respect to the forehead contact portion  412  by only sliding the pad  32  among the attachment portions  416 A to  416 C without detaching the pad  32  from the forehead contact portion  412 . 
     (Second Modification) 
       FIG. 6  is a view illustrating a forehead contact portion  512  according to a second modification. The forehead contact portion  512  is different from the forehead contact portion  312  at a point that an adjustment portion  514  different in configuration from the adjustment portion  314  is provided. The adjustment portion  514  may include a first attachment portion  516 A, a second attachment portion  516 B, and a third attachment portion  516 C. 
     Each of through holes  517 A to  517 F is disposed to partially overlap with a left or right end portion of the forehead contact portion  512 . Accordingly, the through hole  517 A to  517 F includes an opening portion in the left or the right. A length of the opening portion in an up/down direction is smaller than the diameter d 3  of the cylindrical column portion  324  of the pad  32 . In addition, second band attachment portions  315  are provided between the first attachment portion  516 A and the second attachment portion  516 B. However, the second band attachment portions  315  may be provided at different places. 
     To change the attachment position of the pad  32  on the forehead contact portion  512  according to the second modification, the user first moves the engagement protrusions  322  of the pad  32  so as to remove the engagement protrusions  322  leftward or rightward from ones of the opening portions of the through holes  517 A to  517 F, i.e. so as to widen the left and right engagement protrusions  322  of the pad  32  in the left/right direction, while elastically deforming the cylindrical column portions  324  of the pad  32 . Thus, the pad  32  is detached from one of the attachment portions  516 A to  516 C to which the pad  32  was attached. The user then moves the engagement protrusions  322  of the pad  32  so as to press the engagement protrusions  322  leftward or rightward into the opening portions of another of the attachment portions  516 A to  516 C to which the user desires to attach the pad  32  while elastically deforming the cylindrical column portion  324  of the pad  32 . Thus, the user can attach the pad  32  to the attachment portion desired by the user. However, the method for changing the attachment position of the pad  32  on the forehead contact portion  512  is not limited thereto. The attachment position of the pad  32  on the forehead contact portion  512  may be changed by a method similar to or the same as the method according to the aforementioned embodiment. In this case, the user applies rearward force to the pad  32  so as to pull the pad  32  rearward while elastically deforming the truncated cone portions  325 . Thus, the user removes the engagement protrusions  322  from the through holes into which the engagement protrusions  322  were inserted. The user then inserts the engagement protrusions  322  into through holes provided in, of the attachment portions  516 A to  516 C, the attachment portion to which the user desires to attach the pad  32  while elastically deforming the truncated cone portions  325  of the engagement protrusions  322 . 
     (Third Modification) 
       FIG. 7  is a view illustrating a forehead contact portion  612  according to a third modification. The forehead contact portion  612  is different from the forehead contact portion  312  at a point that an adjustment portion  614  different in configuration from the adjustment portion  314  is provided. The adjustment portion  614  may include one slide attachment portion  616  (an example of an attachment portion). The slide attachment portion  616  may include a right slide groove  617 A (an example of an engagement recess) and a left slide groove  617 B (an example of an engagement recess) which are shaped like semicircular arcs respectively to be combined into an approximately circumferential shape of one circle having discontinuous portions  618  provided substantially at the centers of upper and lower end portions of the forehead contact portion  612 . 
     Widths W 2  of the right slide groove  617 A and the left slide groove  617 B are smaller than the diameter d 3  of the cylindrical column portion  324  of the pad  32 . The engagement protrusions  322  of the pad  32  are engaged with the right slide groove  617 A and the left side groove  617 B respectively. 
     To change the attachment position of the pad  32  on the forehead contact portion  612  according to the third modification, the user slides (moves) the pad  32  so as to rotate the pad  32  along the circumference of the circle of the slide attachment portion  616  while elastically deforming the cylindrical column portion  324  of the pad  32 . That is, the user can adjust a position and an angle (posture) of the pad  32  with respect to the forehead contact portion  612  by moving the pad  32  along the right slide groove  617 A and the left slide groove  617 B of the slide attachment portion  616  without detaching the pad  32  from the forehead contact portion  612 . 
     The aforementioned embodiment and the aforementioned modifications are to make the presently disclosed subject matter easy to understand, and do not limit the presently disclosed subject matter. The presently disclosed subject matter can be changed or modified without departing from its gist. 
     In the aforementioned embodiment and the aforementioned modifications, the engagement recesses are provided in the forehead contact portion, and the pad is provided with two engagement protrusions. However, the presently disclosed subject matter is not limited thereto. For example, one through hole (engagement recess) may be provided at the center of the forehead contact portion, and the pad may be provided with one engagement protrusion. When, for example, the engagement protrusion is shaped like a circle in section, the pad can rotate around the through hole. Accordingly, the user can adjust the angle (posture) of the pad with respect to the forehead contact portion. 
     In the aforementioned embodiment and the aforementioned modifications, the position of the pad with respect to the forehead contact portion or the position and the angle (posture) of the pad with respect to the forehead contact portion is adjusted. However, only the angle (posture) of the pad with respect to the forehead contact portion may be adjusted. For example, assume that the pad is configured to move rotationally in the up/down direction in the state in which the pad has been attached to the forehead contact portion. In this case, the user can adjust the angle (posture) of the pad with respect to the forehead contact portion by moving the pad rotationally in the up/down direction. Incidentally, the number of the through holes (engagement recesses) of the forehead contact portion or the engagement protrusions of the pad, and the positions and the shapes of the through holes or the engagement protrusions are not limited as long as the angle (posture) of the pad with respect to the forehead contact portion can be adjusted. 
     In the aforementioned embodiment and the aforementioned modifications, the engagement protrusions and the engagement recesses are provided in the pad and the forehead contact portion respectively. However, the engagement protrusions and the engagement recesses may be provided in the forehead contact portion and the pad respectively. 
     In the aforementioned embodiment and the aforementioned modifications, the engagement recesses are through holes. However, the engagement recesses may be bottomed holes. 
     In the aforementioned embodiment and the aforementioned modifications, the mask  2  is provided with the cushion member  23 . However, the mask  2  may be not provided with the cushion member  23 . 
     In the aforementioned embodiment, the first modification, and the second modification, each of the attachment portions has two through holes paired in the left/right direction. However, the attachment portion may further have another through hole provided between the two through holes. In this case, the attachment portion includes three through holes. 
     In the third modification, the slide attachment portion  616  has an arc shape curved smoothly. However, the slide attachment portion  616  may have an arc shape curved zigzag. 
     In the aforementioned embodiment and the aforementioned modifications, each of the bands  41  is shaped like a belt. However, the band  41  is not limited to the belt shape. The band  41  can be formed into any other shape as long as the band  41  can be placed on the forehead or the head of the patient.