Patent Publication Number: US-10779921-B2

Title: Oral cavity washing device

Description:
RELATED APPLICATIONS 
     This application claims the benefit of Japanese Application No. 2016-225536, filed on Nov. 18, 2016, the entire disclosure of which Application is incorporated by reference herein. 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to an oral cavity washing device configured to wash an intraoral cavity with washing liquid. 
     2. Description of the Related Art 
     An exemplary well-known conventional oral cavity washing device includes a body unit having a tank configured to store washing liquid and a pump configured to discharge the washing liquid, a tube connected to the body unit and configured to allow the washing liquid discharged by the pump to flow through the tube, and a washing unit configured to discharge the washing liquid supplied through the tube. Unexamined Japanese Patent Publication No. 2015-217174 discloses an exemplarily conventional oral cavity washing device. 
     SUMMARY 
     The tube vibrates when the washing liquid discharged from the pump flows through the tube. The vibrating tube may be abraded when the tube comes into contact with the body unit. 
     According to an aspect of the present disclosure, an oral cavity washing device includes: a body unit including a pump configured to discharge washing liquid; a tube connected to the body unit and configured to allow the discharged washing liquid to flow through the tube; a washing unit connected to the tube and configured to discharge the washing liquid; a joint portion configured to detachably attach the washing unit to the body unit; a disposing portion provided at the body unit and configured to allow the tube to be disposed at the disposing portion in a state where the washing unit is attached to the body unit; and an elastic member provided at the disposing portion. 
     The oral cavity washing device according to the present disclosure is unlikely to cause abrasion of the tube. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an oral cavity washing device according to an exemplary embodiment; 
         FIG. 2  is a front view of the oral cavity washing device shown in  FIG. 1 ; 
         FIG. 3  is a plan view of a body unit shown in  FIG. 1 ; 
         FIG. 4  is a perspective view showing a state where a washing unit is detached from the body unit; 
         FIG. 5  is a sectional view taken along line D 5 -D 5  indicated in  FIG. 2 ; 
         FIG. 6  is an enlarged view of a portion A indicated in  FIG. 5 ; 
         FIG. 7  is a sectional view taken along line D 7 -D 7  indicated in  FIG. 2 ; 
         FIG. 8  is an enlarged view of a portion B indicated in  FIG. 7 ; 
         FIG. 9  is an exploded perspective view of the body unit shown in  FIG. 1 ; 
         FIG. 10  is a sectional view taken along line D 10 -D 10  indicated in  FIG. 3 ; 
         FIG. 11  is a sectional view taken along line D 11 -D 11  indicated in  FIG. 2 ; 
         FIG. 12  is a sectional view taken along line D 12 -D 12  indicated in  FIG. 2 ; 
         FIG. 13  is a bottom view of the body unit shown in  FIG. 1 ; 
         FIG. 14  is a sectional view taken along line D 14 -D 14  indicated in  FIG. 13 ; 
         FIG. 15  is a sectional view showing a sixth sealing portion according to a modification; and 
         FIG. 16  is a perspective view of an exemplary oral cavity washing device according to a modification. 
     
    
    
     DETAILED DESCRIPTION 
     Oral Cavity Washing Device in Exemplary Practicable Mode 
     The present disclosure relates to an oral cavity washing device including: a body unit including a pump configured to discharge washing liquid; a tube connected to the body unit and configured to allow the discharged washing liquid to flow through the tube; a washing unit connected to the tube and configured to discharge the washing liquid; a joint portion configured to detachably attach the washing unit to the body unit a disposing portion provided at the body unit and configured to allow the tube to be disposed at the disposing portion in a state where the washing unit is attached to the body unit and an elastic member provided at the disposing portion. The disposing portion has a recess provided at the body unit. The elastic member is provided on an inner surface of the recess. The inner surface has a side surface and a bottom surface. The elastic member covers at least the side surface. The elastic member includes a first surface in contact with the side surface of the inner surface of the recess and a second surface opposite the first surface. The second surface of the elastic member forms a space within the recess and the space is configured to accommodate the tube in a curled state. The elastic member is provided at the disposing portion that is likely to contact with the tube. When the tube vibrates, the elastic member absorbs the vibration. This configuration inhibits abrasion of the tube. 
     The oral cavity washing device is exemplarily configured such that the disposing portion includes a recess provided at the body unit. The recess accommodates the tube in a state where the washing unit is attached to the body unit. The tube is thus unlikely to contact with any other object while the oral cavity washing device is not in use. 
     The oral cavity washing device is exemplarily configured such that the elastic member is provided at an edge of an opening of the recess. The elastic member is provided at the edge of the opening, which may come into strong friction contact with the tube. This configuration thus inhibits abrasion of the tube more effectively. 
     The oral cavity washing device is exemplarily configured such that the elastic member is provided at an inner peripheral surface of the recess. The elastic member is provided at the inner peripheral surface of the recess, which is likely to contact with the tube. This configuration thus inhibits abrasion of the tube more effectively. This configuration also reduces noise generated by contact between the tube and the inner peripheral surface of the recess. 
     The oral cavity washing device is exemplarily configured such that the oral cavity washing device further includes a connecting portion connecting the body unit and the tube, and the connecting portion is provided in the recess, and the elastic member is provided to seal the connecting portion. The elastic member is more valuable with a function of absorbing vibration of the tube and a function of sealing the connecting portion. 
     The oral cavity washing device is exemplarily configured such that the oral cavity washing device further includes a connecting portion connecting the body unit and the tube, and the connecting portion is provided at the disposing portion, and the elastic member is provided to seal the connecting portion. This oral cavity washing device exerts effects similar to effects achieved by the oral cavity washing device described above. 
     Exemplary Embodiment 
       FIG. 1  shows an outer appearance of oral cavity washing device  1 . Oral cavity washing device  1  is used to wash an intraoral cavity, mainly to wash teeth and gums in an oral cavity. Oral cavity washing device  1  is placed on a flat installation surface such as a washstand (not shown). Oral cavity washing device  1  is driven by electric power supplied from an external power supply (not shown) such as a commercial power supply, and is configured to discharge washing liquid into an oral cavity. Examples of the washing liquid include clean water mixed with detergent, and clean water. 
     Oral cavity washing device  1  includes body unit  10 , tube  80 , washing unit  100 , and power source cord PC. Body unit  10  includes device body  20  and tank  70 . Tank  70  has a function of storing washing liquid. Tank  70  is detachably attached to device body  20 , for example. Device body  20  accommodates various elements for driving oral cavity washing device  1 . Device body  20  includes first case  21 , pump  31 , motor  32 , and power source circuit  33  (see  FIG. 7 ). First case  21  accommodates pump  31 , motor  32 , and power source circuit  33 . Pump  31  has a function of discharging the washing liquid stored in tank  70 . Motor  32  has a function of driving pump  31 . Power source circuit  33  has a function of supplying motor  32  with electric power. Power source cord PC is electrically connected to power source circuit  33 . Power source cord PC has a plug PG connected to the external power supply that supplies the power source circuit  33  with electric power. 
     Tube  80  is connected to body unit  10  so as to allow the washing liquid discharged from pump  31  to flow through tube  80 . Washing unit  100  is connected to tube  80  so as to discharge the washing liquid. Washing unit  100  is detachably attached to body unit  10 .  FIG. 1  shows a state where washing unit  100  is attached to body unit  10 . Washing unit  100  is detached from body unit  10  when washing unit  100  is used to wash the intraoral cavity. 
     First case  21  of device body  20  includes a plurality of parts  22  joined together. First case  21  is made of a material such as an acrylonitrile butadiene styrene (ABS) resin. The plurality of parts  22  includes upper lid  23 , case body  30 , bottom lid  24 , and disposing portion  40 . Parts  22  are individually molded products made of a resin material. Upper lid  23 , bottom lid  24 , and disposing portion  40  are each joined to case body  30 . Upper lid  23  configures flat upper surface  23 A of device body  20 . 
     Examples of tube  80  include an extensibly curled tube. It is preferred to determine a type of a material, a diameter, and a thickness of tube  80  in accordance with mobility of washing unit  100  when washing unit  100  is moved around body unit  10 , durability of tube  80 , and the like. Examples of the material for tube  80  include a highly flexible resin material. The resin material is exemplified by an ethylene vinyl acetate copolymer (EVA) resin. The diameter of tube  80  is preferably within an exemplary range from 3.0 mm to 5.0 mm. The diameter of tube  80  can be 4.0 mm. The thickness of tube  80  is preferably within an exemplary range from 0.5 mm to 1.5 mm. The thickness of tube  80  can be 1.0 mm. 
     Washing unit  100  includes second case  101  and nozzle  105 . Nozzle  105  is provided at second case  101  so as to discharge the washing liquid. Second case  101  is made of a material such as an ABS resin. Second case  101  includes grip portion  102 . Grip portion  102  is configured to be gripped by a single hand of a user. Second case  101  includes first end portion  103  and second end portion  104 . First end portion  103  has first end surface  103 A. First end surface  103 A is configured to allow nozzle  105  to be attached to first end surface  103 A. Second end portion  104  is opposite to first end portion  103  of second case  101 . Second end portion  104  has second end surface  104 A. Tube  80  is inserted to second case  101  through second end surface  104 A or the like, and is connected to an inlet of a passage that is provided in second case  101  and allows washing liquid to flow through the passage. Nozzle  105  is connected to an outlet of the passage. 
     Washing unit  100  further includes operation part  106 . Operation part  106  is provided at grip portion  102 . Operation part  106  has a function of opening and closing a check valve (not shown) provided in second case  101 . When operation part  106  is operated to open the check valve, the washing liquid flowing through tube  80  is discharged from discharge port  105 A of nozzle  105 . When operation part  106  is operated to close the check valve, the washing liquid is not discharged from discharge port  105 A of nozzle  105 . 
     Body unit  10  further includes operation part  50  and display part  60 . Operation part  50  has a function of selecting behavior of body unit  10  relevant mainly to discharge of washing liquid. Operation part  50  is provided at upper surface  23 A of device body  20  or the like. Operation part  50  includes a plurality of buttons. The plurality of buttons includes first button  51 , second button  52 , and third button  53 . First button  51  has a function of powering ON and powering OFF body unit  10 . Second button  52  has a function of increasing hydraulic pressure of the washing liquid discharged from pump  31 . Third button  53  has a function of decreasing the hydraulic pressure of the washing liquid discharged from pump  31 . Second button  52  and third button  53  are operated to regulate the hydraulic pressure of the washing liquid discharged from pump  31  within a range of discharge pressure of pump  31 . The range of the discharge pressure of pump  31  is preferably from 3.0 kgf/cm 2  to 8.0 kgf/cm 2  or the like. The washing liquid discharged from discharge port  105 A of nozzle  105  has hydraulic pressure varied in accordance with the hydraulic pressure of the washing liquid discharged from pump  31 . 
     Pump  31  has maximum discharge pressure preferably higher than predetermined maximum discharge pressure. The predetermined maximum discharge pressure is preferably determined in accordance with a relation with power of washing off plaque and the like in the oral cavity by the washing liquid discharged from discharge port  105 A of nozzle  105 . The predetermined maximum discharge pressure is preferred to be at least 4 kgf/cm 2  or the like. The predetermined maximum discharge pressure is more preferred to be at least 6 kgf/cm 2  or the like. The preferred predetermined maximum discharge pressure can be 8 kgf/cm 2 . 
     Display part  60  has a function of displaying various information associated with operation at operation part  50 . Display part  60  includes a plurality of light emitting diode (LED) lamps provided on upper surface  23 A of device body  20  or the like. The LED lamps each have a lighting state varied in accordance with the hydraulic pressure of the washing liquid regulated with use of second button  52  and third button  53 . 
     Disposing portion  40  is joined to case body  30  so as to be provided with tube  80  in the state where washing unit  100  is attached to body unit  10 . Disposing portion  40  includes recess  41 . Recess  41  is configured to accommodate tube  80 . Recess  41  includes opening  41 A opened to front surface  30 D of case body  30 . 
       FIG. 2  is a front view of oral cavity washing device  1  with washing unit  100  attached to body unit  10  and without nozzle  105  that is removed from second case  101 . Second case  101  of washing unit  100  is configured to cause second end portion  104  to face disposing portion  40  in the state where washing unit  100  is attached to body unit  10 . This configuration allows second end portion  104  to be easily gripped for easy detachment of washing unit  100  from body unit  10 . 
     Second case  101  is configured to allow first end surface  103 A to substantially be flush with upper surface  23 A of device body  20  in the state where washing unit  100  is attached to body unit  10 . This configuration allows such a positional relation between first end surface  103 A and upper surface  23 A of device body  20  to serve as a guide for attaching washing unit  100  to body unit  10 . The state where first end surface  103 A is substantially flush with upper surface  23 A of device body  20  includes a state where there is no difference in height between first end surface  103 A and upper surface  23 A of device body  20 , and a state where there is provided a slight difference in height between first end surface  103 A and upper surface  23 A of device body  20 . The slight difference in height is sized such that device body  20  and washing unit  100  being unlikely to obstruct a hand moving around body unit  10  are equally effective or are regarded as being substantially equally effective to the case where there is provided no difference in height between upper surface  23 A of device body  20  and first end surface  103 A of washing unit  100 . 
     Body unit  10  is preferred to have an elliptical or approximately elliptical two-dimensional shape in a planar view. The two-dimensional shape of body unit  10  relates to a state where tank  70  is attached to device body  20 , and is equal to a two-dimensional shape of body unit  10  projected on a plane perpendicular to a center axis of body unit  10 .  FIG. 3  is a plan view of oral cavity washing device  1  not provided with washing unit  100 . The two-dimensional shape of body unit  10  in a planar view is exemplified by a circle as an example of the elliptical shape. When the two-dimensional shape of body unit  10  is an elliptical shape or an approximately elliptical shape, body unit  10  and tube  80  have a small contact area in a state where tube  80  (see  FIG. 1 ) is in contact with body unit  10 . Tank  70  and device body  20  each have a two-dimensional shape in a planar view, exemplified by a semi-ellipse or an approximate semi-ellipse. The two-dimensional shape of device body  20  in a planar view relates to the state where tank  70  is attached to device body  20 . 
     Body unit  10  has a three-dimensional shape preferably like a column, an approximate column, a truncated cone, an approximate truncated cone, a cone, an approximate cone, a twin cone, an approximate twin cone, an ellipsoid, or an approximate ellipsoid. The three-dimensional shape of body unit  10  relates to the state where tank  70  is attached to device body  20 . As shown in  FIG. 1 , the three-dimensional shape of body unit  10  is exemplified by an elliptical column as an example of the column. In a case where the three-dimensional shape of body unit  10  is one of those exemplified above, body unit  10  and tube  80  have a small contact area in the state where tube  80  is in contact with body unit  10 . In the case where body unit  10  is shaped like the twin cone, the approximate twin cone, the ellipsoid, or the approximate ellipsoid, body unit  10  is preferably provided, at a bottom portion, with a support portion (not shown) allowing body unit  10  to stably be placed on the installation surface. 
     Terms expressing the two-dimensional shape and the three-dimensional shape of body unit  10  are classified into terms not provided with “approximate” as a prefix and terms provided with “approximate” as a prefix. The terms provided with “approximate” include the approximate ellipse, the approximate column, the approximate truncated cone, the approximate cone, the approximate twin cone, the approximate ellipsoid, and the approximate semi-ellipse. Graphics each described with a term not including “approximate” will be referred to as basic graphics. Graphics each described with a term including “approximate” will be referred to as similar graphics. With regard to the feature that body unit  10  and tube  80  have a small contact area, the similar graphics include a graphic being substantially equally effective to a case where the two-dimensional shape or the three-dimensional shape of body unit  10  has a basic graphic, and a graphic being significantly more effective in comparison to a conventional oral cavity washing device including body unit  10  having a planar side surface. Oral cavity washing device  1  is improved in designability because body unit  10  has the two-dimensional shape and the three-dimensional shape in a planar view each having a basic graphic or a similar graphic. 
     The similar graphic of the two-dimensional shape has various examples. According to a first example, the similar graphic of the two-dimensional shape partially includes a straight line. According to a second example, the similar graphic of the two-dimensional shape partially includes a curved line having an outside center. According to a third example, the similar graphic of the two-dimensional shape includes features of both the first and second examples. 
     The similar graphic of the three-dimensional shape has various examples. According to a first example, the similar graphic of the three-dimensional shape partially includes a plane. According to a second example, the similar graphic of the three-dimensional shape partially includes a projection. According to a third example, the similar graphic of the three-dimensional shape partially includes a recess. According to a fourth example, the similar graphic of the three-dimensional shape includes at least two features of the first to third examples. 
     Upper surface  23 A of device body  20  is substantially flush with flat upper surface  75 A of tank  70  or the like in the state where tank  70  is attached to device body  20 . Body unit  10  is thus unlikely to obstruct a hand, washing unit  100 , tube  80 , and the like, which move around body unit  10 . 
     The state where upper surface  23 A of device body  20  is substantially flush with upper surface  75 A of tank  70  includes a state where there is no difference in height between upper surface  23 A of device body  20  and upper surface  75 A of tank  70 , and a state where there is provided a slight difference in height between upper surface  23 A of device body  20  and upper surface  75 A of tank  70 . The slight difference in height is sized such that body unit  10  being unlikely to obstruct a hand, washing unit  100 , tube  80 , and the like moving around body unit  10  is equally effective or is regarded as being substantially equally effective to the case where there is provided no difference in height between upper surface  23 A of device body  20  and upper surface  75 A of tank  70 . 
       FIG. 4  shows a state where washing unit  100  is detached from body unit  10 . Washing unit  100  further includes detaching switch  107 . Detaching switch  107  has a function of detaching nozzle  105  from second case  101 . Detaching switch  107  is provided at a rear surface of first end portion  103  of second case  101 , for example. 
     Oral cavity washing device  1  further includes elastic member  42 .  FIG. 4  shows a dotted portion corresponding to elastic member  42 . Elastic member  42  is made of an elastic material or the like, which is unlikely to abrade tube  80  when elastic member  42  is in contact with tube  80 . Examples of the elastic material include elastomer. Elastic member  42  is provided at disposing portion  40 . Elastic member  42  is provided at disposing portion  40  that is likely to contact tube  80 . When driven pump  31  (see  FIG. 7 ) vibrates tube  80  located at disposing portion  40 , elastic member  42  absorbs the vibration of tube  80 . This configuration inhibits abrasion of tube  80 . This configuration also reduces noise generated by vibration in comparison to a case where vibrating tube  80  comes into contact with a portion not covered with elastic member  42 . 
     Elastic member  42  includes first elastic member  42 A and second elastic member  42 B. First elastic member  42 A is provided at edge  41 B (see  FIG. 5 ) of opening  41 A of recess  41 , for example. First elastic member  42 A can be provided at entire edge  41 B of opening  41 A. First elastic member  42 A is provided at edge  41 B of opening  41 A, which may come into strong friction contact with tube  80 . This configuration thus inhibits abrasion of tube  80  more effectively. Moreover, this configuration reduces noise generated by vibration in comparison to a case where vibrating tube  80  comes into contact with a portion not covered with first elastic member  42 A. 
     Second elastic member  42 B is provided at inner peripheral surface  41 C and bottom surface  41 D of recess  41 , for example. Second elastic member  42 B can be provided entirely at inner peripheral surface  41 C and bottom surface  41 D of recess  41 . Second elastic member  42 B is provided at inner peripheral surface  41 C and bottom surface  41 D of recess  41 , which are likely to come into contact with tube  80 . This configuration thus inhibits abrasion of tube  80  more effectively. Moreover, this configuration reduces noise generated by vibration in comparison to a case where vibrating tube  80  comes into contact with a portion not covered with second elastic member  42 B. 
     Oral cavity washing device  1  further includes joint portion  110 . Joint portion  110  has a function of detachably attaching washing unit  100  to body unit  10 . Joint portion  110  joins body unit  10  and washing unit  100  by magnetic force or the like. This configuration allows washing unit  100  approaching body unit  10  to be joined to body unit  10  by magnetic force of joint portion  110 . 
     Case body  30  further includes recess  34 . Recess  34  is provided in front surface  30 D of case body  30  or the like. Recess  34  is shaped correspondingly to an outline of washing unit  100 . Recess  34  has surface  34 A configuring a space in recess  34 , and surface  34 A is curved correspondingly to the outline of washing unit  100 , for example. Washing unit  100  is disposed at recess  34  of body unit  10  in a state where joint portion  110  joins washing unit  100  to body unit  10 . Joint portion  110  thus fixes posture of washing unit  100  joined to body unit  10 . 
     Case body  30  includes first outer wall  30 A and second outer wall  30 B. First outer wall  30 A configures an outline of case body  30 . Second outer wall  30 B as well as first outer wall  30 A configure the outline of case body  30 . Second outer wall  30 B is provided at part of recess  34  of case body  30 , for example. Second outer wall  30 B is surrounded with first outer wall  30 A. Detaching switch  107  provided at the rear surface of second case  101  of washing unit  100  forms a gap between the rear surface of second case  101  and surface  34 A of recess  34  in the state where washing unit  100  is attached to body unit  10 . Second outer wall  30 B rises outward from first outer wall  30 A of case body  30  to decrease the gap. 
     Joint portion  110  includes first joint portion  111  and second joint portion  112 . First joint portion  111  is provided at front surface  30 D of case body  30 . First joint portion  111  is provided at surface  34 A of recess  34  of case body  30 , for example. First joint portion  111  includes magnet  111 A, yoke  111 B (see  FIG. 6 ), and first accommodating portion  111 C (see  FIG. 6 ). Examples of magnet  111 A include a neodymium magnet. Yoke  111 B faces second outer wall  30 B of case body  30  with magnet  111 A being interposed therebetween (see  FIG. 6 ), to allow a magnetic flux of magnet  111 A to effectively be applied to second joint portion  112 . Yoke  111 B is made of a material such as low carbon steel. First accommodating portion  111 C is provided at case body  30 , so as to accommodate magnet  111 A and yoke  111 B. First accommodating portion  111 C includes second outer wall  30 B and inner wall  30 C provided in case body  30  (see  FIG. 6 ). 
     Recess  34  of case body  30  extends in a height direction of body unit  10 , for example. Recess  34  has lower end portion  34 B connected to recess  41  of disposing portion  40 . Magnet  111 A is provided on an inner surface side of recess  34  in second outer wall  30 B of case body  30 . Magnet  111 A is provided on the inner surface side of recess  34  at a center in the height direction of body unit  10 , for example. This configuration allows force of joint portion  110 , which joins washing unit  100  to body unit  10 , to be applied in a well-balanced manner to entire washing unit  100 , and more effectively stabilizes the posture of washing unit  100  joined to body unit  10 . 
     Second case  101  includes first outer wall  101 A and second outer wall  101 B. First outer wall  101 A configures an outline of second case  101 . Second outer wall  101 B as well as first outer wall  101 A configure the outline of second case  101 . Second outer wall  101 B is provided at part of the rear surface of second case  101 , for example. Second outer wall  101 B is surrounded with first outer wall  101 A, and is recessed from first outer wall  30 A toward an inside of second case  101 . Second outer wall  101 B of second case  101  is shaped to be fitted to second outer wall  30 B of case body  30 . This configuration increases magnetic force applied between first joint portion  111  and second joint portion  112 . 
     Second joint portion  112  is provided at washing unit  100 . Second joint portion  112  is provided at a rear surface of grip portion  102 , in an intermediate portion in a height direction, for example. Second joint portion  112  includes ferromagnet  112 A and second accommodating portion  112 B (see  FIG. 6 ). Examples of ferromagnet  112 A include a cold-rolled steel sheet. This configuration prevents second joint portion  112  from attracting any ferromagnet around oral cavity washing device  1  in the state where washing unit  100  is detached from body unit  10 . Ferromagnet  112 A configures second joint portion  112 , to achieve reduction in production cost in comparison to a case where each of first joint portion  111  and second joint portion  112  includes a magnet. Second accommodating portion  112 B includes second outer wall  101 B and inner wall  101 D provided in second case  101  (see  FIG. 6 ). 
     First outer wall  30 A of case body  30  includes restricting portion  35 . Restricting portion  35  has a function of restricting downward shift relative to body unit  10 , of washing unit  100  attached to body unit  10 . Restricting portion  35  is provided at lower end portion  34 B of recess  34  of case body  30 , for example. Restricting portion  35  is covered with elastic member  42  as exemplarily shown. 
     First outer wall  101 A of second case  101  includes contact portion  108 . Contact portion  108  is provided at a rear surface of second end portion  104  of second case  101 , for example. Contact portion  108  comes into contact with restricting portion  35  when washing unit  100  shifts downward relatively to body unit  10 . This configuration positions washing unit  100  in a height direction relatively to body unit  10  because contact portion  108  comes into contact with restricting portion  35  when washing unit  100  joined to body unit  10  is shifted downward relatively to body unit  10  due to own weight of washing unit  100 , or the like. 
     As shown in  FIG. 5 , joint portion  110  and restricting portion  35  fix the position of washing unit  100  relative to body unit  10  in the state where washing unit  100  is attached to body unit  10 . In the state where joint portion  110  and restricting portion  35  fix the position of washing unit  100  relative to body unit  10 , first end surface  103 A of second case  101  is substantially flush with upper surface  23 A of device body  20 . 
       FIG. 6  shows a relation between first joint portion  111  and second joint portion  112 . Magnet  111 A of first joint portion  111  is fixed to second outer wall  30 B of case body  30  in first accommodating portion  111 C. Yoke  111 B is attached to magnet  111 A. Second outer wall  30 B of case body  30  has thickness TA 1  smaller than thickness TA 2  of first outer wall  30 A of case body  30  in a portion around second outer wall  30 B in the height direction of body unit  10 . This configuration increases magnetic force applied between first joint portion  111  and second joint portion  112 . 
     Second outer wall  101 B of second case  101  includes thin portion  101 C. Ferromagnet  112 A of second joint portion  112  is fixed to thin portion  101 C of second outer wall  101 B in second accommodating portion  112 B. Thin portion  101 C of second outer wall  101 B of second case  101  has thickness TB 1  smaller than thickness TB 2  of first outer wall  101 A of second case  101  in a portion around second outer wall  101 B in the height direction of washing unit  100 . This configuration increases magnetic force applied between first joint portion  111  and second joint portion  112 . 
     As shown in  FIG. 7 , washing unit  100  is fitted to recess  34  of case body  30  so as to be attached to body unit  10 . Oral cavity washing device  1  thus configured is unlikely to have a two-dimensional shape including a large projection in a planar view. Oral cavity washing device  1  is thus more effectively improved in designability. 
     As shown in  FIG. 8 , second outer wall  30 B of case body  30  has the thickness TA 1  smaller than thickness TA 3  of first outer wall  30 A of case body  30  in a portion around second outer wall  30 B in a width direction of body unit  10 . Thin portion  101 C of second outer wall  101 B of second case  101  has the thickness TB 1  smaller than thickness TB 3  of first outer wall  101 A of second case  101  in a portion around second outer wall  101 B in a width direction of washing unit  100 . 
       FIG. 9  shows exploded various elements configuring body unit  10 . This figure does not show part of body unit  10 . 
     Tank  70  includes tank body  71 , bottom portion  72 , drain port  73  (see  FIG. 7 ), outlet  74  (see  FIG. 12 ), lid  75 , and handle  76 . Tank body  71  is provided to store washing liquid. The washing liquid is poured into tank body  71  through opening  71 A. Bottom portion  72  configures a bottom surface of tank body  71 . Drain port  73  has a function of discharging the washing liquid stored in tank body  71 . There is provided a float valve (not shown) configured to regulate an amount of the drained washing liquid. Drain port  73  is provided at an inner surface of bottom portion  72 . Outlet  74  is provided at an outer surface of bottom portion  72  so as to communicate with drain port  73 . Lid  75  is detachably attached to tank body  71 , and opens and closes opening  71 A of tank body  71 . Lid  75  being attached to tank body  71  configures upper surface  75 A of tank  70 . Handle  76  is provided in tank body  71  at a position adjacent to opening  71 A. 
     Case body  30  includes support portion  36 . Support portion  36  has a function of supporting bottom portion  72  of tank  70 . Support portion  36  is shaped similarly to tank  70  in a planar view. Support portion  36  includes water supply port  36 A. Water supply port  36 A is connectable with outlet  74  of tank  70 . When tank  70  is attached to device body  20 , outlet  74  of tank  70  is connected to water supply port  36 A of support portion  36 . Water supply port  36 A is connected to pump  31 . The washing liquid stored in tank  70  is discharged from drain port  73 , passes through outlet  74  and water supply port  36 A, and flows into pump  31 . 
     Operation part  50  further includes panel  54 . Buttons  51  to  53  and display part  60  are attached to panel  54 . Upper lid  23  of first case  21  includes a plurality of holes  23 B allowing buttons  51  to  53  to be exposed to outside. Panel  54  includes a plurality of holes  54 A allowing buttons  51  to  53  to be inserted to holes  54 A. After panel  54  is fixed to case body  30  with a plurality of screws  55 , upper lid  23  is joined to case body  30 . 
     Oral cavity washing device  1  further includes sealing structure  120 . Sealing structure  120  has a function of inhibiting entry of water to first case  21 . Sealing structure  120  is provided at first case  21 . Oral cavity washing device  1  has an international protection class IPX7 or the like. 
     Sealing structure  120  includes first sealing portion  121  and second sealing portion  122 . First sealing portion  121  seals seams  131 A to  131 C between the plurality of parts  22  on an outline of first case  21 . First sealing portion  121  includes first sealing member  121 A, second sealing member  121 B, and third sealing member  121 C. 
     First sealing member  121 A has a function of sealing seam  131 A between upper lid  23  and case body  30 . First sealing member  121 A is made of a material such as rubber. When first sealing member  121 A is sandwiched between panel  54  of operation part  50  and case body  30  and panel  54  is fixed to case body  30  with screws  55 , first sealing member  121 A seals seam  131 A between upper lid  23  and case body  30 . 
     Second sealing member  121 B has a function of sealing seam  131 B between bottom lid  24  and case body  30 . Second sealing member  121 B is made of a material such as rubber. When second sealing member  121 B is sandwiched between bottom lid  24  and case body  30  and bottom lid  24  is fixed to case body  30  with a screw (not shown) or the like, second sealing member  121 B seals seam  131 B between bottom lid  24  and case body  30 . 
     Third sealing member  121 C has a function of sealing seam  131 C between disposing portion  40  and case body  30 . Third sealing member  121 C is made of a material such as rubber. When third sealing member  121 C is sandwiched between disposing portion  40  and case body  30  and disposing portion  40  is fixed to case body  30  with screw  43  (see  FIG. 4 ), third sealing member  121 C seals seam  131 C between disposing portion  40  and case body  30 . 
     Second sealing portion  122  seals seams  132 A to  132 C between first case  21  and operation part  50 . Second sealing portion  122  includes first sealing member  122 A, second sealing member  122 B, and third sealing member  122 C. 
     First sealing member  122 A has a function of sealing seam  132 A between upper lid  23  and first button  51 . First sealing member  122 A is made of a material such as rubber. First sealing member  122 A is provided to seal a gap between panel  54  and first button  51  inserted to hole  54 A of panel  54  (see  FIG. 10 ), for example. When first sealing member  122 A is placed to seal the gap between first button  51  and panel  54  and upper lid  23  is joined to case body  30 , first sealing member  122 A seals seam  132 A between upper lid  23  and first button  51 . Second sealing member  122 B has a function of sealing seam  132 B between upper lid  23  and second button  52 . Third sealing member  122 C has a function of sealing seam  132 C between upper lid  23  and third button  53 . Second sealing member  122 B and third sealing member  122 C are configured substantially similarly to first sealing member  122 A. 
     As shown in  FIG. 10 , sealing structure  120  further includes sealing member  61 . Sealing member  61  has a function of sealing seam  62  between upper lid  23  and display part  60 . Sealing member  61  is made of a material such as rubber. Sealing member  61  covers display part  60  to seal display part  60 , for example. When sealing member  61  is placed to cover display part  60  and upper lid  23  is joined to case body  30 , sealing member  61  seals seam  62  between upper lid  23  and display part  60 . Sealing member  61  optionally configures part of second sealing portion  122 . 
     As shown in  FIG. 11 , oral cavity washing device  1  further includes connecting portion  81 . Connecting portion  81  connects body unit  10  and tube  80 . Connecting portion  81  is provided in recess  41  of disposing portion  40  to configure a connection between case body  30  and tube  80 , for example. 
     Sealing structure  120  further includes third sealing portion  123 . Third sealing portion  123  has a function of sealing seam  133  between connecting portion  81  and body unit  10 . Third sealing portion  123  is embodied by elastic member  123 A or the like. Elastic member  123 A is configured by an O-ring or the like. Elastic member  123 A is provided at disposing portion  40  to seal connecting portion  81 . When third sealing portion  123  is sandwiched between connecting portion  81  and disposing portion  40  and connecting portion  81  is fixed to case body  30  via disposing portion  40  with screw  82 , third sealing portion  123  seals seam  133  between connecting portion  81  and body unit  10 . Oral cavity washing device  1  further includes two elastic members  123 B,  123 C that inhibit leakage of water flowing from flow passage  31 A connecting pump  31  and tube  80  into body unit  10 . Elastic members  123 B,  123 C are each configured by an O-ring or the like. 
     Oral cavity washing device  1  further includes pump accommodating portion  37 . Pump accommodating portion  37  has a function of accommodating pump  31 . Pump accommodating portion  37  is provided in support portion  36  of case body  30 , for example. Pump accommodating portion  37  is configured by outer wall  36 B of support portion  36 . Pump accommodating portion  37  includes pump support portion  37 A supporting pump  31 . Pump accommodating portion  37  and pump support portion  37 A configure part of case body  30 , and are made of a resin material similarly to a remaining portion of case body  30 . Pump support portion  37 A includes a rib (not shown) provided at an inner surface of outer wall  36 B. Pump  31  is fixed to the rib with a coupler or the like. The coupler includes fitting structures provided at both pump  31  and the rib. 
     The coupler is exemplified by a plurality of screws  38 . 
     As shown in  FIG. 12 , sealing structure  120  further includes fourth sealing portion  124 . Fourth sealing portion  124  has a function of sealing water supply port  36 A of case body  30 . Fourth sealing portion  124  is embodied by elastic member  124 A. Elastic member  124 A is configured by an O-ring or the like. Fourth sealing portion  124  is fitted in water supply port  36 A to seal water supply port  36 A. This configuration is thus unlikely to allow entry of water to body unit  10  also in a state where tank  70  is detached from device body  20 . 
     Oral cavity washing device  1  further includes elastic member  124 B sealing a gap between outlet  74  of tank  70  and water supply port  36 A of case body  30 . Elastic member  124 B is configured by an O-ring or the like. Elastic member  124 B is fixed to a periphery of outlet  74  of tank  70 . Elastic member  124 B inhibits external leakage of the washing liquid discharged from outlet  74  of tank  70  in the state where tank  70  is attached to device body  20 . 
     Sealing structure  120  further includes fifth sealing portion  125  (see  FIG. 5 ). Fifth sealing portion  125  configures waterproof layer  125 A. Waterproof layer  125 A has a function of covering power source circuit  33 . Waterproof layer  125 A is provided as a resin layer formed by potting or the like. Examples of the resin material for waterproof layer  125 A include a urethane resin. Waterproof layer  125 A thus achieves further improvement in waterproof property of power source circuit  33 .  FIG. 5  includes a two-dot chain line indicating waterproof layer  125 A. 
     As shown in  FIG. 13 , device body  20  further includes wiring passage  25 . Wiring passage  25  holds power source cord PC led out of first case  21 . Wiring passage  25  is provided at bottom surface  24 A of bottom lid  24 . Wiring passage  25  is biforked, for example. Wiring passage  25  includes first outlet  25 A and second outlet  25 B. Outlets  25 A,  25 B allow power source cord PC to be led out of device body  20 . First outlet  25 A and second outlet  25 B are axially symmetrical with respect to a center line in a width direction of device body  20 . Outlets  25 A,  25 B are provided laterally to bottom lid  24  or the like.  FIG. 13  exemplarily shows power source cord PC led out of first outlet  25 A. In this configuration, power source cord PC is unlikely to restrict installation of oral cavity washing device  1 . 
     As shown in  FIG. 14 , device body  20  further includes lead-out portion  26 . Lead-out portion  26  allows power source cord PC to be led out of first case  21 . Lead-out portion  26  is provided at bottom surface  24 A of bottom lid  24 . 
     Sealing structure  120  further includes sixth sealing portion  126 . Sixth sealing portion  126  seals a gap between bottom lid  24  and power source cord PC in lead-out portion  26 . Sixth sealing portion  126  includes bushing  126 A and sealing member  126 B. Bushing  126 A is provided at power source cord PC so as to be inserted to lead-out portion  26 . Bushing  126 A is formed integrally with power source cord PC, for example. Sealing member  126 B has a function of sealing a gap between bushing  126 A and lead-out portion  26 . Sealing member  126 B is configured by an O-ring or the like. When sealing member  126 B is sandwiched between bushing  126 A and lead-out portion  26  and bushing  126 A is fixed to bottom lid  24  with screw  126 C, sealing member  126 B seals the gap between bushing  126 A and lead-out portion  26 . Sealing structure  120  including first to sixth sealing portions  121  to  126  satisfies the class IPX7. Sealing structure  120  is thus unlikely to allow entry of water to body unit  10  even in a case where body unit  10  is immersed in water, so that body unit  10  is washed efficiently. 
     Exemplary steps of using oral cavity washing device  1  will be described with reference to  FIG. 1 . 
     Oral cavity washing device  1  is used by a user or the like in a following manner. In a first step, a predetermined amount of the washing liquid is poured into tank  70 , and tank  70  is attached to device body  20 . In a second step, first button  51  of body unit  10  is operated to power on oral cavity washing device  1 . When oral cavity washing device  1  is powered on, pump  31  (see  FIG. 7 ) starts being driven. In a third step, washing unit  100  is detached from body unit  10 , and discharge port  105 A of nozzle  105  is directed into an oral cavity. In a fourth step, operation part  106  of washing unit  100  is operated to discharge the washing liquid from discharge port  105 A. The washing liquid discharged from discharge port  105 A thus washes the intraoral cavity. 
     In a fifth step, washing unit  100  is attached to body unit  10  upon interruption or termination of washing the intraoral cavity with oral cavity washing device  1 . Upon interruption of washing the intraoral cavity with oral cavity washing device  1  in the fifth step, the third to fifth steps are repeated. 
     The washing liquid discharged from pump  31  passes through tube  80  in a process of discharging the washing liquid from discharge port  105 A, so that tube  80  is vibrated due to hydraulic pressure of the washing liquid flowing through tube  80 , for example. Magnitude of vibration of tube  80  depends on magnitude of hydraulic pressure of the washing liquid discharged from pump  31 . Vibrating tube  80  thus comes into contact with body unit  10 . Oral cavity washing device  1  includes elastic member  42  at disposing portion  40  that is likely to contact with tube  80 , and elastic member  42  thus absorbs vibration of tube  80 . This configuration inhibits abrasion of tube  80 . This configuration also reduces noise generated by contact between tube  80  and disposing portion  40 . Furthermore, body unit  10  has the circular two-dimensional shape and the columnar three-dimensional shape in a planar view. Even when tube  80  comes into contact with body unit  10 , body unit  10  and tube  80  have a small contact area in this configuration. Tube  80  is thus unlikely to be abraded even in a case where pump  31  is driven with tube  80  being in contact with body unit  10 . 
     When washing unit  100  approaches body unit  10  so as to be attached to body unit  10 , magnetic force of joint portion  110  joins washing unit  100  to body unit  10 . Washing unit  100  can be attached to body unit  10  even though washing unit  100  is not accurately positioned relatively to body unit  10 . 
     Modifications 
     The exemplary embodiment exemplarily describes the oral cavity washing device in a practicable mode of the present disclosure, and does not intend to limit the mode. The present disclosure can include, in addition to the exemplary embodiment, following modifications of the exemplary embodiment, any mode achieved by combining at least two of the modifications having no conflict, and the like.
         Sixth sealing portion  126  can be modified appropriately in terms of its configuration. According to a first example, as shown in  FIG. 15 , bushing  126 A is ultrasonically welded, press fitted, or pressure welded to lead-out portion  26  to seal the gap between bushing  126 A and lead-out portion  26 . According to a second example, power source cord PC is formed integrally with bottom lid  24  to seal the gap between bottom lid  24  and power source cord PC.   Sealing structure  120  can be modified appropriately in terms of its configuration. According to a first example, first sealing portion  121  can optionally exclude at least one of first sealing member  121 A, second sealing member  121 B, and third sealing member  121 C. According to a second example, second sealing portion  122  optionally exclude at least one of first sealing member  122 A, second sealing member  122 B, and third sealing member  122 C. According to a third example, sealing structure  120  can optionally exclude at least one of first sealing portion  121 , second sealing portion  122 , third sealing portion  123 , fourth sealing portion  124 , fifth sealing portion  125 , and sixth sealing portion  126 .   The two-dimensional shape of body unit  10  in a planar view can be modified appropriately. For example, the two-dimensional shape of body unit  10  in a planar view can have a corner.   It is possible to appropriately modify the relation between upper surface  23 A of device body  20  and upper surface  75 A of tank  70 . According to a first example, upper surface  23 A of device body  20  is higher than upper surface  75 A of tank  70 . According to a second example, upper surface  23 A of device body  20  is lower than upper surface  75 A of tank  70 . According to a third example, part of upper surface  75 A of tank  70  covers upper surface  23 A of device body  20  such that upper surface  75 A of tank  70  configures an entire upper surface of body unit  10 . According to a fourth example, part of upper surface  23 A of device body  20  covers upper surface  75 A of tank  70  such that upper surface  23 A of device body  20  configures the entire upper surface of body unit  10 . According to a fifth example, tank  70  is detachably attached to upper surface  23 A of device body  20 . The relation between upper surface  23 A of device body  20  and upper surface  75 A of tank  70  relates to the state where tank  70  is attached to device body  20 .   It is possible to appropriately modify the relation between first end surface  103 A of second case  101  and upper surface  23 A of device body  20 . According to a first example, first end surface  103 A is higher than upper surface  23 A of device body  20 . According to a second example, first end surface  103 A is lower than upper surface  23 A of device body  20 . The relation between first end surface  103 A of second case  101  and upper surface  23 A of device body  20  relates to the state where washing unit  100  is attached to body unit  10 .   It is possible to appropriately modify the relation between recess  34  of case body  30  and recess  41  of disposing portion  40 . For example, recess  34  of case body  30  is displaced from recess  41  of disposing portion  40  in the width direction of body unit  10 . Second end portion  104  of second case  101  according to this example does not face disposing portion  40  in the state where washing unit  100  is attached to body unit  10 . Examples of second case  101  having second end portion  104  not facing disposing portion  40  include shortened second case  101 .   Elastic member  42  can be modified appropriately in terms of its configuration. According to a first example, first elastic member  42 A is provided at part of edge  41 B of opening  41 A. According to a second example, second elastic member  42 B is provided at part of inner peripheral surface  41 C of recess  41 . According to a third example, second elastic member  42 B is provided at part of bottom surface  41 D of recess  41 . According to a fourth example, elastic member  42  can optionally exclude at least one of first elastic member  42 A and second elastic member  42 B.   First outer wall  30 A of case body  30  can optionally exclude restricting portion  35 . According to this example, washing unit  100  attached to body unit  10  is positionally fixed with respect to body unit  10  by only joint portion  110 . First outer wall  101 A of second case  101  can optionally exclude contact portion  108 .   It is possible to appropriately determine whether or not magnet  111 A is provided in recess  34  at the center in the height direction of body unit  10 . According to a first example, magnet  111 A is provided in recess  34  in an upper portion in the height direction of body unit  10 . According to a second example, magnet  111 A is provided in recess  34  in a lower portion in the height direction of body unit  10 .   It is possible to appropriately determine whether or not magnet  111 A is provided in first accommodating portion  111 C. Magnet  111 A is provided on an outer surface side of recess  34  or the like. First joint portion  111  according to this example excludes first accommodating portion  111 C. Case body  30  can optionally exclude recess  34 .   It is possible to appropriately determine whether or not ferromagnet  112 A is provided in second accommodating portion  112 B. Ferromagnet  112 A is provided on an outer surface side of second case  101  or the like. Second joint portion  112  according to this example excludes second accommodating portion  112 B.       

     It is possible to appropriately modify the relation between thickness TA 1  of second outer wall  30 B of case body  30  and thicknesses TA 2 , TA 3  of first outer wall  30 A of case body  30  in the portion around second outer wall  30 B. According to a first example, thickness TA 1  is substantially equal to at least one of thicknesses TA 2 , TA 3 . According to a second example, thickness TA 1  is larger than at least one of thicknesses TA 2 , TA 3 .
         It is possible to appropriately modify the relation between thickness TB 1  of thin portion  101 C in second outer wall  101 B of second case  101  and thicknesses TB 2 , TB 3  of first outer wall  101 A of second case  101  in the portion around second outer wall  101 B. According to a first example, thickness TB 1  is substantially equal to at least one of thicknesses TB 2 , TB 3 . According to a second example, thickness TB 1  is larger than at least one of thicknesses TB 2 , TB 3 .   Joint portion  110  can be modified appropriately in terms of its configuration. According to a first example, first joint portion  111  includes a ferromagnet, and second joint portion  112  includes a magnet. The configuration according to this example achieves reduction in production cost in comparison to the case where each of first joint portion  111  and second joint portion  112  includes a magnet. According to a second example, first joint portion  111  includes magnet  111 A, and second joint portion  112  includes a magnet attracting magnet  111 A. The magnet included in joint portion  110  can alternatively be an electromagnet. According to a third example, joint portion  110  physically joins body unit  10  and washing unit  100 . Such physical joining is achieved in an exemplary case where a first one of first joint portion  111  and second joint portion  112  includes a hook and a second one of first joint portion  111  and second joint portion  112  includes a hooked portion configured to be joined to the hook. Oral cavity washing device  1  can optionally exclude joint portion  110 .   It is possible to appropriately determine whether or not operation part  50  is provided at upper surface  23 A of device body  20 . Operation part  50  is provided at a side surface of device body  20  or the like.   It is possible to appropriately determine whether or not display part  60  is provided at upper surface  23 A of device body  20 . Display part  60  is provided at the side surface of device body  20  or the like. Oral cavity washing device  1  can optionally exclude display part  60 .   Oral cavity washing device  200  according to a modification differs from oral cavity washing device  1  according to the exemplary embodiment in the following points, and is configured substantially identically to oral cavity washing device  1  according to the exemplary embodiment in remaining points. Elements of oral cavity washing device  200  according to the modification in common with the elements of oral cavity washing device  1  according to the exemplary embodiment will be denoted by identical reference signs and will not be described partially or entirely.       

       FIG. 16  shows oral cavity washing device  200  including body unit  210 , tube  80 , washing unit  220 , and power source cord PC. Body unit  210  includes device body  211 , support base  212 , tank  213 , and operation part  214 . Device body  211 , tank  213 , operation part  214 , and washing unit  220  are configured substantially identically to device body  20 , tank  70 , operation part  50 , and washing unit  100  according to the exemplary embodiment. Tank  213  is detachably attached onto a top of device body  211 . Support base  212  is configured to allow washing unit  220  to be mounted thereon, and is formed integrally with device body  211 . For example, washing unit  220  and body unit  210  are joined to each other by magnetic force when washing unit  220  is mounted on support base  212 . 
     Body unit  210  further includes disposing portion  215 . Disposing portion  215  is provided at body unit  210  so as to be provided with tube  80  in a state where washing unit  100  is attached to body unit  210 . Disposing portion  215  is exemplarily configured by a portion surrounded with washing unit  220  mounted on support base  212 , side surface  211 A of device body  211 , upper surface  212 A of support base  212 , and side surface  213 A of tank  213 . 
     Oral cavity washing device  200  further includes elastic member  230 .  FIG. 16  shows a dotted portion corresponding to elastic member  230 . Elastic member  230  is made of an elastic material or the like, which is unlikely to abrade tube  80  when elastic member  42  is in contact with tube  80 . Examples of the elastic material include elastomer. Elastic member  230  is provided at disposing portion  215 . Elastic member  230  includes first elastic member  231 , second elastic member  232 , and third elastic member  233 . First elastic member  231  is provided at side surface  211 A of device body  211 . Second elastic member  232  is provided at upper surface  212 A of support base  212 . Third elastic member  233  is provided at side surface  213 A of tank  213 . Elastic member  230  is provided at disposing portion  215  that is likely to contact with tube  80 , to absorb vibration of vibrating tube  80 . This configuration inhibits abrasion of tube  80 . Elastic member  230  can optionally exclude one or two of first elastic member  231 , second elastic member  232 , and third elastic member  233 . 
     Oral cavity washing device  200  further includes connecting portion  81  and elastic member  240 . Connecting portion  81  is provided at disposing portion  215 . Elastic member  240  is configured by an O-ring or the like. Elastic member  240  is provided at disposing portion  215  so as to seal connecting portion  81 . This configuration is unlikely to allow entry of water to body unit  210  through connecting portion  81 . 
     The oral cavity washing device according to the present disclosure is applicable to any type of an oral cavity washing device for home use or business use.