Patent Publication Number: US-10307778-B2

Title: Trigger-type liquid dispenser

Description:
TECHNICAL FIELD 
     The present disclosure relates to a trigger-type liquid ejection device (hereinafter, called the trigger-type liquid dispenser) that is attached to a mouth of a container containing a liquid and that dispenses the liquid contained in the container through a nozzle. 
     BACKGROUND 
     Dispensers may be attached to mouths of containers containing liquids, such as an antimold, a detergent, a sizing agent for textiles, household wax, a hair liquid, an aromatic, a repellent, a pesticide, and a medicine. As an example of such a dispenser, an existing trigger-type liquid dispenser dispenses such a liquid in the form of spray or foam through a nozzle by actuating a pump in response to operation of a trigger. 
     Such a trigger-type liquid dispenser includes a dispenser main body fitted to the mouth of the container by, for example, a fitting cap. The dispenser main body is fitted with a pump and is also provided with a delivery flow path of the liquid pressure-fed to the pump, and the nozzle is fitted to a delivery port, which is an outlet end of the delivery flow path. The nozzle is provided with a dispensing hole having a smaller diameter than the delivery flow path. After pressure-fed to the delivery port through the delivery flow path by the pump, the liquid is dispensed to the outside through the dispensing hole. It is also known that, in some cases, the nozzle is fitted rotatably to the dispenser main body and that rotating the nozzle permits the dispensing hole to be switched between an opened and a closed state. 
     Such a nozzle is generally formed into a shape including a partition wall provided with the dispensing hole, a cylindrical outer circumferential wall integrally provided around an outer circumference of the partition wall, and an annular locking projection integrally provided on an inner circumferential surface of the outer circumferential wall to protrude from the inner circumferential surface toward the inner side in the radial direction, by injection molding a resin material with use of a mold. On the other hand, the dispenser main body is provided integrally with a cylindrical fitted portion that communicates with the delivery port. The fitted portion is also provided, on an outer circumferential surface thereof, with a projecting portion integrally. With the outer circumferential wall of the nozzle being fitted to the outer side of the fitted portion and with the locking projection of the nozzle being in undercut engagement with the projecting portion, the nozzle is rotatably fitted to the fitted portion while being engaged with the fitted portion. 
     CITATION LIST 
     Patent Literature 
     PTL1: JPH11290731A 
     SUMMARY 
     Technical Problem 
     In the trigger-type liquid dispenser, a large amount of the liquid is dispensed in the form of spray or foam through the small dispensing hole provided in the nozzle. This means that pressure is increased in the delivery flow path and in the nozzle at the time of dispensing the liquid. Accordingly, fitting strength of the nozzle with respect to the fitted portion needs to be enhanced by increasing the degree of overlap in the undercut engagement between the locking projection, which is provided on the outer circumferential wall of the nozzle, and the projecting portion, which is provided on the outer circumferential surface of the fitted portion. 
     However, the attempt to increase the degree of overlap in the undercut engagement poses the following problem. That is to say, when the nozzle is fitted to the outer side of the fitted portion, the locking projection strongly contacts the projecting portion, and plastic deformation so-called a burr occurs. This causes a variation in position of the nozzle fitted to the fitted portion of the dispenser main body. 
     Accordingly, the present disclosure is to provide a trigger-type liquid dispenser that maintains the fitting strength of the nozzle with respect to the fitted portion sufficiently and that also improves fitting stability of the nozzle by preventing the plastic deformation caused when the nozzle is fitted. 
     Solution to Problem 
     One of aspects of the present disclosure resides in a trigger-type liquid dispenser including: a dispenser main body fitted to a mouth of a container containing a liquid; a pump configured, in response to operation of a trigger, to be actuated to pressure-feed the liquid contained in the container to a delivery port through a delivery flow path provided in the dispenser main body; and a nozzle fitted to the dispenser main body to dispense, to outside, the liquid pressure-fed to the delivery port. The dispenser main body includes a cylindrical-shaped fitted portion communicating with the delivery port. The nozzle includes a partition wall, which covers an opening end of the fitted portion and which is provided with a dispensing hole, and a tubular-shaped outer circumferential wall, which is contiguous with an outer circumference of the partition wall to cover an outer circumference of the fitted portion. The nozzle is rotatable with respect to the fitted portion between an opened position, in which the dispensing hole communicates with the delivery port, and a closed position, in which the dispensing hole is blocked from the delivery port. The outer circumferential wall includes a locking projection that protrudes toward an inner side in a radial direction from an inner circumferential surface of the outer circumferential wall and that is in undercut engagement with a projecting portion provided on an outer circumferential surface of the fitted portion to thereby hold the nozzle in engagement with the fitted portion. The locking projection is provided, in an inner edge portion thereof, with a concave portion, in which a degree of the undercut engagement with the projecting portion is reduced when the nozzle is located between the opened and the closed position. 
     In a preferred embodiment of the trigger-type liquid dispenser according to the present disclosure, the nozzle is configured in a manner such that the nozzle comes to the closed position when being rotated 90 degrees to one side with respect to the fitted portion from the opened position, and the concave portion is arranged to engage with the projecting portion in a state where the nozzle is rotated 45 degrees in a direction toward the closed position from the opened position. 
     In another preferred embodiment of the trigger-type liquid dispenser according to the present disclosure, the outer circumferential wall includes a rib that protrudes toward the inner side in the radial direction from the inner circumferential surface of the outer circumferential wall and that abuts against the projecting portion in a state where the locking projection is in undercut engagement with the projecting portion. 
     In yet another preferred embodiment of the trigger-type liquid dispenser according to the present disclosure, the nozzle includes: a nozzle main body in which the partition wall and the outer circumferential wall are formed integrally; and a nozzle cap body that is fitted to the nozzle main body, that is configured to cover the dispensing hole in an openable and closable manner via a hinge, and that is configured to change a dispensing form. 
     Advantageous Effect 
     The present disclosure provides a trigger-type liquid dispenser that maintains the fitting strength of the nozzle with respect to the fitted portion sufficiently and that also improves the fitting stability of the nozzle by preventing the plastic deformation caused when the nozzle is fitted. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the accompanying drawings: 
         FIG. 1  is a side sectional view of a trigger-type liquid dispenser according to one of embodiments of the present disclosure; 
         FIG. 2  is an enlarged sectional view illustrating a trigger-type liquid dispenser of  FIG. 1 ; and 
         FIG. 3A  is a pair of a front view and an X-X sectional view illustrating a nozzle and a fitted portion of a trigger-type liquid dispenser of  FIG. 1 , and 
         FIG. 3B  is a pair of a front view and a Y-Y sectional view illustrating how a nozzle is fitted to a fitted portion. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure will be described in more detail below by illustration with reference to the drawings. Note that, in the specification, the claims, the abstract, and the drawings herein, the side (corresponding to the upper side in  FIG. 1 ) on which a ceiling wall of a shroud included in a dispenser main body, which is later described, is located is defined as upper direction, and the side (corresponding to the lower side in  FIG. 1 ) on which a fitting cap is disposed is defined as lower direction. Furthermore, the side (corresponding to the left side in  FIG. 1 ) on which the nozzle of the dispenser main body is disposed is defined as front direction, and the opposite side (corresponding to the right side in  FIG. 1 ) is defined as rear direction. Moreover, the directions that are orthogonal to the upper-lower direction and the front-rear direction (the directions that are orthogonal to the drawing in  FIG. 1 ) are defined as lateral sides (left and right directions). 
     A trigger-type liquid dispenser  1  according to one of embodiments of the present disclosure illustrated in  FIG. 1  may be attached to a mouth  2   a  of a container  2  in use. The container  2  contains a liquid, such as an antimold, a detergent, a sizing agent for textiles, household wax, a hair liquid, an aromatic, a repellent, a pesticide, and a medicine, as the content liquid.  FIG. 1  illustrates the state in which the trigger-type liquid dispenser  1  is attached to the mouth  2   a  of the container  2 . 
     The trigger-type liquid dispenser  1  includes a dispenser main body  10 , which is fitted to the mouth  2   a  of the container  2 . The dispenser main body  10  includes a resin-made body portion  11  and a pump  12 , which is fitted to the body portion  11 . 
     A lower end of the body portion  11  serves as a coupling tube  13 , and a fitting cap  14  is held to the coupling tube  13  in a manner such that the fitting cap  14  is rotatable relative to the coupling tube  13 . The fitting cap  14  is formed in a cylindrical shape and is provided, on an inner circumferential surface thereof, with a female screw  14   a . The body portion  11  is fixed to the mouth  2   a  of the container  2  by screw-connecting the female screw  14   a  to a male screw  2   b , which is provided on an outer circumferential surface of the mouth  2   a  of the container  2 , in the state where the coupling tube  13  is fitted to the mouth  2   a  of the container  2 . Additionally, reference numeral  15  denotes a sealing member that seals between the mouth  2   a  of the container  2  and the coupling tube  13 . 
     The body portion  11  is formed to have a substantially L-shape appearance including a standing portion  16 , which extends from the coupling tube  13  in a direction extending along the central axis of the coupling tube  13 , and also including an extension portion  17 , which extends in a direction orthogonal to the standing portion  16 . The standing portion  16  is provided inside thereof with an intake flow path P 1 , which communicates with the coupling tube  13 . The intake flow path P 1  has a lower end (corresponding to a lower end of an upright and inverted dual mechanism  30 , which is described later) to which a drawing tube  18 , which is inserted into the container  2 , is connected. On the other hand, the extension portion  17  is provided with a delivery flow path P 2 , which extends in the direction orthogonal to the intake flow path P 1 . The delivery flow path P 2  is provided, on a front end thereof, with a delivery port  19 . 
     The pump  12  includes a cylinder  20 , which is attached to the body portion  11 , and a piston  21 , which is displaceably assembled in the cylinder  20 . The inside of the cylinder  20  communicates with the intake flow path P 1  and the delivery flow path P 2  via an outlet/inlet hole  22 . 
     The intake flow path P 1  is provided, in a portion thereof that is located on the lower side (i.e., on the upstream side) of the outlet/inlet hole  22 , with the first check valve  23 . The first check valve  23  operates to permit the liquid to flow from the inside of the container  2  toward the outlet/inlet hole  22  and to prevent the liquid, after being discharged through the outlet/inlet hole  22  in response to actuation of the pump  12 , from flowing toward the container  2  through the intake flow path P 1 . Similarly, the delivery flow path P 2  is provided, in a portion inside thereof that is located on the upper side (i.e., on the downstream side) of the outlet/inlet hole  22 , with the second check valve  24 . The second check valve  24  operates to permit the liquid, after being discharged through the outlet/inlet hole  22  in response to actuation of the pump  12 , to flow toward the delivery port  19  through the delivery flow path P 2  and to prevent the liquid from flowing from the delivery port  19  toward the outlet/inlet hole  22 . 
     To the body portion  11 , a trigger (operation lever)  25  is fitted. The trigger  25 , on its one end side, is supported swingably by the body portion  11  about a pivot shaft  26 . The trigger  25  is provided, in a middle portion thereof, with a pin member  27 , which engages with a concave portion  21   a , which is provided in a front end of the piston  21 . Thus, the trigger  25  is rotatably coupled to the front end of the piston  21  by the pin member  27 . With the trigger  25 , a front end of a curve-shaped plate spring S, which has a base end fixed to and held by the body portion  10 , is engaged. The plate spring S urges the trigger  25  toward a direction (i.e., a clockwise direction about the pivot shaft  26  in the figure) away from the pump  12 . Additionally, the body portion  11  and the pump  12  are covered by a shroud  28 , and the trigger  25  protrudes from the lower side of the shroud  28 . 
     When the trigger  25  is pulled toward the pump  12  manually, the first check valve  23  is closed, and the piston  21  increases the liquid pressure inside the cylinder  20 . Consequently, the liquid contained in the cylinder  20  is delivered from the outlet/inlet hole  22  into the delivery flow path P 2  through the second check valve  24 . On the other hand, when the trigger  25  is released from the operation, the trigger  25  is returned to its initial position due to resilience of the plate spring S. In conjunction with the return movement, the second check valve  24  is closed, the first check valve  23  is opened, and the liquid contained in the container  2  is drawn from the outlet/inlet hole  22  into the cylinder  21  via the tube  18  and the intake flow path P 1 . Additionally, the cylinder  20  is provided with an ambient air introduction port  20   a , which is exposed to the outside when the trigger  25  is operated to its stroke limit. Air drawn through the ambient air introduction port  20   a  is then drawn into the container  2  through an annular-shaped gap defined between the cylinder  20  and the body portion  11 , through a vent hole  11   a , which is provided in the body portion  11 , and through a gap defined between the upright and inverted dual mechanism  30  and the body portion  11 . Accordingly, after the liquid is dispensed, the space in the container  2  is replaced with air. By thus repeating pulling and releasing operations of the trigger  25 , the pump  12  may be actuated to draw the liquid contained in the container  2  through the intake flow path P 1  and to pressure-feed the liquid to the delivery port  19  through the delivery flow path P 2 . 
     The body portion  11  and the pump  12  do not need to be configured as above, and it is possible to adopt a variety of configurations or structures, which permit the pump  12  to be actuated in response to operation of the trigger  25  to pressure-feed the liquid from the inside of the container  2  to the delivery port  19 . 
     Between the intake flow path P 1  and the tube  18 , there is provided the upright and inverted dual mechanism  30 , which permits the liquid contained in the container  2  to be supplied to the pump  12  regardless of whether the container  2 , to which the trigger-type liquid dispenser  1  is fitted, is in an upright or an inverted position. The upright and inverted dual mechanism  30  includes a check valve unit  31 . When the container  2  is in the upright position, the check valve unit  31  is in its closed state where a ball-shaped valve body  31   a  closes an outlet hole  31   c  of a valve chamber  31   b , so that the liquid may be introduced to the intake flow path P 1  via the tube  18 . On the other hand, when the container  2  is placed in the inverted position, the check valve unit  31  is brought into its opened state by the valve body  31   a  being displaced in the valve chamber  31   b  in a direction away from the outlet hole  31   c , so that the liquid pooled inside the coupling tube  13  may be introduced from an inlet opening  31   d , which is provided in a side wall of the check valve unit  31 , to the intake flow path P 1  via the valve chamber  31   b , the outlet hole  31   c , and a flow path  31   e , which is used during inversion. Thus, the liquid contained in the container  2  may be supplied to the pump  12  both in the upright and inverted positions. 
     To a front end of the extension portion  17  of the body portion  11 , a nozzle  40  is fitted. The nozzle  40  is used to dispense the liquid, after being pressure-fed from the container  2  to the delivery port  19  by the pump  12 , to the outside. 
     As illustrated in  FIG. 2 , the front end of the extension portion  17  of the dispenser main body  10  is provided integrally with a fitted portion  17   a , to which the nozzle  40  is fitted. The fitted portion  17   a  is formed in a cylindrical shape protruding from the front end of the extension portion  17 , and the delivery port  19 , which is an outlet end of the delivery flow path P 2 , is open to the lower side of the inside of the fitted portion  17   a . That is to say, the fitted portion  17   a , in the inside thereof, communicates with the delivery port  19  of the delivery flow path P 2 . Furthermore, the front end of the extension portion  17  is provided integrally with a columnar-shaped switch shaft portion  43 , whose central axis is aligned with the central axis of the fitted portion  17   a.    
     In the present embodiment, the nozzle  40  has a double-block structure combining a nozzle main body  41  and a nozzle cap body  42 . The nozzle main body  41  and the nozzle cap body  42  are each obtained by injection molding a resin material with use of a mold. Additionally, the nozzle  40  does not necessarily need to have the double-block structure, and the nozzle main body  41  and the nozzle cap body  42  may be molded integrally. Alternatively, the nozzle  40  may be configured only by the nozzle main body  41 . 
     The nozzle main body  41  includes a plate-shaped partition wall  41   a , which covers an opening end of the fitted portion  17   a , and an outer circumferential wall  41   b , which is contiguous with an outer circumference of the partition wall  41   a  to cover an outer circumference of the fitted portion  17   a . As can be seen from  FIGS. 3A and 3B , the outer circumferential wall  41   b  has a tubular shape that is substantially square as viewed from the front side. 
     The partition wall  41   a  of the nozzle main body  41  is provided with a dispensing hole  44 , which extends through the partition wall  41   a  along the central axis of the outer circumferential wall  41   b . The dispensing hole  44  is a small hole that is sufficiently smaller in sectional area than the delivery port  19 . The partition wall  41   a  is further provided, on an inner surface thereof that faces to the fitted portion  17   a , integrally with a cylindrical-shaped closing tubular portion  41   d , which is disposed coaxially with the dispensing hole  44 . With the closing tubular portion  41   d  being fitted on the inner side of the fitted portion  17   a , the partition wall  41   a  closes the opening end of the fitted portion  17   a . Moreover, the partition wall  41   a  is provided, on the inner surface thereof, integrally with a switch tubular portion  41   e , which is disposed coaxially with the closing tubular portion  41   d  on the inner side of the closing tubular portion  41   d . The switch tubular portion  41   e  is fitted on the outer side of the switch shaft portion  43 . The closing tubular portion  41   d  and the switch tubular portion  41   e  are rotatable relative to the fitted portion  17   a  and the switch shaft portion  43 . That is to say, the nozzle main body  41  is rotatable with respect to the fitted portion  17   a  about the axis of the partition wall  41   a  of the nozzle main body  41 . 
     The switch shaft portion  43  is provided, on an outer circumferential surface in a predetermined range of the front end side thereof, with at least one groove extending in the axis line direction. The switch tubular portion  41   e  is also provided, on an inner circumferential surface thereof, with at least one groove extending in the axis line direction. These grooves are not in communication with each other when the nozzle main body  41  (nozzle  40 ) is in its closed position. On the other hand, these grooves are in communication with each other when the nozzle main body  41  is in its opened position in which the nozzle main body  41  is rotated 90 degrees with respect to the fitted portion  17   a  from the closed position. Accordingly, when the nozzle main body  41  is in its closed position, the dispensing hole  44  is in its closed state in which the liquid is prevented from being dispensed due to the dispensing hole  44  being blocked from the delivery port  19 . When the nozzle main body  41  is in its opened position, the dispensing hole  44  is in its opened state in which the liquid may be dispensed through the dispensing hole  44  communicating with the delivery port  19 . By thus rotating the nozzle  40  between the closed and the opened position, opening and closing of the dispensing hole  44  may be switched. 
     Herein,  FIGS. 3A and 3B  illustrate the state before the nozzle main body  41  is fitted to the fitted portion  17   a . Front views are on the left side, and an X-X sectional view and a Y-Y sectional view are on the right side. As illustrated in the sectional views of  FIGS. 3A and 3B , the fitted portion  17   a  is provided, on an outer circumferential surface thereof, with a pair of projecting portions  47 , which are in undercut engagement with locking projections  46 , which are later described. These protruding portions  47  are each formed in a plate shape protruding to the outer side in the radial direction from the outer circumferential surface of the fitted portion  17   a  and has a width in the circumferential direction that is approximately ¼ of the width of the corresponding locking projection  46 . Additionally, although in the present embodiment the pair of projecting portions  47  is disposed on the left and the right side on the outer circumferential surface of the fitted portion  17   a , the present disclosure is not limited to this embodiment. The pair of projecting portions  47  may be disposed on the upper and the lower side or any other sides. 
     As illustrated in the front views of the nozzle main body  41  of  FIGS. 3A and 3B , the partition wall  41   a  of the nozzle main body  41  is provided with a pair of through holes  45 , which extends along a joining portion between the partition wall  41   a  and the outer circumferential wall  41   b . These through holes  45  each extend in a range of approximately 90 degrees about the central axis of the outer circumferential wall  41   b  and are formed as a pair of arc-shaped holes disposed in point symmetry about the central axis of the outer circumferential wall  41   b.    
     Furthermore, the outer circumferential wall  41   b  of the nozzle main body  41  is provided with the pair of locking projections  46 , which protrudes toward the inner side in the radial direction from an inner circumferential surface of the outer circumferential wall  41   b . In the state where the nozzle main body  41  is fitted to the fitted portion  17   a , the locking projections  46  are in undercut engagement with the projecting portions  47  of the fitted portion  17   a . Accordingly, the nozzle main body  41  (the nozzle  40 ) is locked in a direction extending along the central axis thereof and is prevented from being detached from the fitting portion  17   a  by the projecting portions  47  while being held rotatably with respect to the fitted portion  17   a . Additionally, the pair of locking projections  46  are disposed in point symmetry with each other within a range of approximately 90 degrees. Accordingly, even when the nozzle main body  41  is rotated between the closed and the opened position, the locking projections  46  are locked by the projecting portions  47 , and the nozzle main body  41  is prevented from being detached from the fitted portion  17   a.    
     As illustrated in  FIGS. 3A and 3B , these locking projections  46  are each formed in an arc shape extending circumferentially along the inner circumferential surface of the outer circumferential wall  41   b  in the same range as the range of the corresponding through hole  45  so that the locking projection  46  is located in the range overlapping with the corresponding through hole  45  as viewed from a direction extending along the central axis of the outer circumferential wall  41   b.    
     As illustrated in  FIGS. 3A and 3B , each locking projection  46  is provided, in an inner edge portion in the radial direction thereof, with a concave portion  46   a , which is recessed toward the outer side in the radial direction. The concave portion  46   a  is provided in a middle region in the circumferential direction of the inner edge portion of the locking projection  46 . A width in the circumferential direction of the concave portion  46   a  is slightly greater than that of the corresponding projecting portion  47 . As illustrated in  FIG. 3B , the concave portion  46   a  in the present embodiment is provided in a manner such that the concave portion  46   a  comes to a position corresponding to the projecting portion  47  when the nozzle main body  41  is rotated 45 degrees in a rotational direction from the opened or the closed position. The degree of overlap in the undercut engagement between the locking projection  46  and the projecting portion  47  is reduced in the concave portion  46   a  of the locking projection  46 . Accordingly, to fit the nozzle main body  41  to the fitted portion  17   a , the concave portion  46   a , in alignment with the projecting portion  47 , is simply pushed in the axis line direction. By doing so, the locking projection  46  climbs over the projecting portion  47  easily. This prevents occurrence of the plastic deformation due to strong contact between the locking projection  46  and the projecting portion  47 . 
     Furthermore, the outer circumferential wall  41   b  is provided with ribs  50 , which protrude toward the inner side in the radial direction from the inner circumferential surface of the outer circumferential wall  41   b . The ribs  50  abut against the projecting portions  47  in the state where the locking projections  46  are in undercut engagement with the projecting portions  47 . This prevents rattling of the nozzle main body  41  in the state where the nozzle main body  41  is fitted to the fitted portion  17   a . In order to provide the effect of reducing the rattling, the ribs  50  do not necessarily need to abut against the projecting portions  47  as long as the ribs  50  are provided to be adjacent to the projecting portions  47  in the state where the locking projections  46  are in undercut engagement with the projecting portions  47 . Furthermore, when being provided intermittently in the circumferential direction, the ribs  50  reduce sliding friction caused by rotation of the nozzle  40  between the opened and the closed position. Additionally, in the present embodiment, the ribs  50  are arranged in four locations, that is to say, in the upper, the lower, the left, and the right part, on the outer circumferential wall  41   b  so that the ribs  50  abut against the projecting portions  47  when the nozzle  40  is in the opened and the closed position. The width in the circumferential direction of each rib  50  is approximately ¼ the width of each locking projection  46 . 
     Additionally, reference numeral  48  denotes a projection provided on the outer circumferential surface of the fitted portion  17   a . The projection  48  climbs over a projection  49 , which is provided on the inner circumferential surface of the outer circumferential wall  41   b , and this provides a click sensation when the nozzle main body  41  is rotated to the opened or the closed position. Furthermore, each locking projection  46  is provided, on both sides thereof, with stoppers S (which are not shown). Each of these stoppers S, against which the corresponding projecting portion  47  abuts, regulates the rotational angle of the nozzle main body  41  to be 90 degrees. By rotating the nozzle main body  41  in the range of 90 degrees, the dispensing hole  44  may be switched from the closed to the opened state, or from the opened to the closed state. 
     The nozzle cap body  42  includes a holding portion  42   a , which is fitted to the inner side of the outer circumferential wall  41   b , and a cover portion  42   c , which is provided in an openable and closable manner via a hinge  42   b . The holding portion  42   a  is provided with a locking claw  42   d . The locking claw  42   d  is inserted through the through holes  45  of the nozzle main body  41  to be in undercut engagement with a rear surface of the partition wall  41   a , thereby holding the nozzle cap body  42  in engagement with the nozzle main body  41 . The cover portion  42   c  is provided, on a front end thereof, integrally with a tab portion  42   e , which is held for opening and closing operations of the cover portion  42   c . The cover portion  42   c  is also provided with a columnar-shaped projection  42   f , with which the liquid dispensed in the form of spray from the dispensing hole  44  collides to be turned into foam in the closed position. The cover portion  42   c , which covers the dispensing hole  44  in the closed position and which serves to change the form of dispensing the liquid dispensed from the dispensing hole  44 , may have any shape etc. Furthermore, the cover portion  42   c  may also be a closing cap that simply covers the dispensing hole  44  to prevent the content liquid from being dispensed. 
     In the trigger-type liquid dispenser  1  with the above configuration according to the present embodiment, at the time of fitting the nozzle main body  41  to the fitted portion  17   a , the nozzle main body  41  is pushed in easily with a little force by aligning the concave portions  46   a  with the projecting portions  47  as illustrated in  FIG. 3B . Besides, the plastic deformation between the locking projections  46  and the projecting portions  47  is prevented, and the fitting stability of the nozzle  40  is improved. 
     Meanwhile, after the nozzle  40  is fitted, the nozzle  40  is basically arranged in the opened or the closed position. Accordingly, operation is not feasible in the state where the concave portions  46   a  are in engagement with the projecting portions  47 . Especially when the liquid contained in the container  2  is dispensed, the nozzle  40  is in the opened state. This ensures, as illustrated in  FIG. 3A , a sufficient degree of overlap in the undercut engagement between the locking projections  46  and the projections  47 , and a sufficient fitting strength of the nozzle  40  with respect to the fitted portion  17   a  is obtained. Accordingly, even when pressure is increased in the delivery flow path P 2  and in the nozzle  40 , there is no fear of the nozzle  40  falling off, and this permits safe use. 
     Furthermore, in the trigger-type liquid dispenser  1  according to the present embodiment, the outer circumferential wall  41   b  is provided with the ribs  50 , which abut against the projecting portions  47  in the state where the locking projections  46  are in undercut engagement with the projecting portions  47 . This prevents rattling of the nozzle  40  and accordingly, improves operability and stabilizes the dispensing form of the liquid. 
     Moreover, in cases where the nozzle cap body  42  is provided as in the trigger-type liquid dispenser  1  according to the present embodiment, the form of dispensing the liquid may be switched. Accordingly, the dispensing form may be changed depending on applications, and convenience is further improved. 
     REFERENCE SIGNS LIST 
       1  Trigger-type liquid dispenser 
       2  Container 
       2   a  Mouth 
       2   b  Male screw 
       10  Dispenser main body 
       11  Body portion 
       11   a  Vent hole 
       12  Pump 
       13  Coupling tube 
       14  Fitting cap 
       14   a  Female screw 
       15  Sealing member 
       16  Standing portion 
       17  Extension portion 
       17   a  Fitted portion 
       18  Tube 
       19  Delivery port 
       20  Cylinder 
       20   a  Ambient air introduction port 
       21  Piston 
       21   a  Concave portion 
       22  Outlet/inlet hole 
       23  First check valve 
       24  Second check valve 
       25  Trigger 
       26  Pivot shaft 
       27  Pin member 
       28  Shroud 
       30  Upright and inverted dual mechanism 
       31  Check valve unit 
       31   a  Valve body 
       31   b  Valve chamber 
       31   c  Outlet hole 
       31   d  Inlet opening 
       31   e  Flow path used during inversion 
       40  Nozzle 
       41  Nozzle main body 
       41   a  Partition wall 
       41   b  Outer circumferential wall 
       41   d  Closing tubular portion 
       41   e  Switch tubular portion 
       42  Nozzle cap body 
       42   a  Holding portion 
       42   b  Hinge 
       42   c  Cover portion 
       42   d  Locking claw 
       42   e  Tab portion 
       43  Switch shaft portion 
       44  Dispensing hole 
       45  Through hole 
       46  Locking projection 
       46   a  Concave portion 
       47  Projecting portion 
       48  Projection 
       49  Projection 
       50  Rib 
     P 1  Intake flow path 
     P 2  Delivery flow path 
     S Plate spring