Patent Publication Number: US-9839923-B2

Title: Showerhead

Description:
FIELD OF THE INVENTION 
     The present invention refers to a showerhead of the type to be installed in bathrooms of private, collective or public use, and presenting a hollow body which is associated with a water supply pipe and inferiorly closed by a perforated plate, defining the sieve of the showerhead and whose holes, for water passage, may be easily cleared from eventual impurities or clogs, by a simple manual operation of the user while using the showerhead, or automatically, by operation of the showerhead itself. 
     PRIOR ART 
     It is well known the problem related to the progressive accumulation of impurities and clogs in the holes of the sieve, which tend to reduce or even block the passage of water through said holes, reducing the amount of water released by the showerhead, compromising its operational performance and impairing the quality of the bath. 
     In many known constructions, the operation of cleaning and unclogging the sieve holes requires dismounting the showerhead, said operation being usually complex and time-consuming and effected with the aid of tools and with the showerhead out of operation, that is, it cannot be made during the bath and by means of simple and quick manual actuation of the user. 
     Other showerheads known in the art are provided with a cleaning device, which allows the user to displace, manually and during the bath, a frame internal do the body of the showerhead and which carries pins to be introduced, each one and in a relatively tight manner, into a respective hole of the sieve, in order to clean the latter. While allowing for a simple manual operation which can be carried out during the bath, said known solution presents the inconvenience of effecting the cleaning only by the simultaneous introduction of all the pins into the respective holes of the sieve of the showerhead, which holes present a reduced cross section area which becomes easily clogged. Thus, in case one of the holes of the sieve is blocked upstream by a particle of impurity seated thereon, not only the respective pin but also all the other pins will be impeded of penetrating in the holes of the sieve. In this situation, dismounting the showerhead is necessary, resulting in the inconveniences of this type of operation. 
     Some known showerhead constructive solutions present the function of automatic cleaning the sieve holes, which is carried out during operation of the showerhead. 
     In one of the known solutions, disclosed in Brazilian document PI9504809-0, the showerhead is provided with a cleaning device formed by an inner grid, affixed in the interior of the hollow body of the showerhead, above the sieve and incorporating a plurality de cleaning pins, turned downward and which are shaped and positioned to be individually inserted in the interior of a respective hole in the sieve of the showerhead, when the latter has its control valve turned off, that is, when the showerhead is brought to the off condition. 
     According to the construction of the document mentioned above, the sieve is rotatively affixed in the hollow body of the showerhead and axially displaceable between an active position, with the showerhead in the on condition, in which the through-holes of the sieve are kept spaced away from the cleaning pins of the inner grid, and a rest position, with the showerhead in the off condition, in which the holes of the sieve are fitted in the cleaning pins of the inner grid, promoting the cleaning and unclogging of the sieve holes. An elastic element, mounted in the interior of the hollow body, forces the sieve constantly to the rest position. However, when the showerhead is brought to the on condition, the hydraulic pressure, acting on the sieve, overcomes the resistance imposed by the elastic element, separating the sieve from the cleaning pins and clearing the sieve holes for the free water discharge upon operation of the showerhead. 
     Said known construction, although promoting the cleaning of the sieve holes, presents the drawback of maintaining the sieve visually retracted in the interior of the hollow body when the showerhead is in the off condition, making difficult to fully block the water remaining within the hollow body after the user turns off the showerhead after his bath. After the showerhead is turned off and, particularly, when it is found in an even slightly inclined position, the water retained therewithin cannot drain rapidly, due to the reduced diameter of the sieve holes, allowing the showerhead to undesirably drip water for a time, even after being taken to the off condition. 
     Another aspect of such known construction results from the reduced diameter (about 1 mm) of the sieve holes, which facilitates its obstruction by dirt. Any grain with a larger diameter will be clogged in one of the sieve holes and will not be removed by the cleaning pin, which may further impair the approximation of the sieve with all the cleaning pins of the inner grid, impeding the automatic cleaning operation to take place and leading to the need of making a troublesome dismounting operation of the sieve for its manual cleaning. 
     Other constructive solution is described in Brazilian document PI0300309-4, which comprises an unclogging device defined by a cleaning element incorporating a plurality of cleaning pins, turned downwardly and positioned to be, as a function of the operational conditions of the showerhead, inserted in or removed from the interior of the through-holes defined in the sieve of the showerhead. 
     According to the particular construction of PI0300309-4 mentioned above, the cleaning element, rotatively affixed in the hollow body of the showerhead, is axially displaceable in the interior of said hollow body, from an inoperative position, in which the cleaning pins are kept spaced away from the sieve holes, while the showerhead is in the on condition, that is, in the bath condition, and by actuation of the hydraulic pressure, exerted by the water flow, under a first moving element (diaphragm), coupled to the cleaning element, in order to overcome the resistance exerted by a second resilient moving element (spring), which constantly forces the cleaning element to an operative position, in which the cleaning pins are inserted, with a slight gap, in the sieve holes, thus remaining while the showerhead is in the off condition. The cleaning pins are conducted to the operative position when the showerhead is turned off, in order to provide the self-cleaning and/or the unclogging of the natural impurities, which are normally brought to the hydraulic supply pipe, wherefrom they flow to the through-holes of the sieve, upon operation of the showerhead in the on condition. 
     While providing the cleaning and unclogging of the through-holes of the sieve, aiming at maintaining the water flow defined in the showerhead project, said second solution also presents a sieve with holes of reduced diameter (about 1 mm), facilitating obstruction thereof caused by dirt. As already mentioned in relation to the other prior art document, grains with larger diameter tend to be trapped in the sieve holes, and cannot be removed by the cleaning pins, which can impair the approximation of the sieve to the inner cleaning pins, impeding the automatic cleaning function to be carried out and leading to the need of making a laborious disassembly of the sieve for its manual cleaning. 
     Besides the drawback mentioned above, said second known solution requires the provision of a diaphragm which, in case of undergoing a rupture, even small, will provoke leaks which, depending on the proportions and on the hydraulic supply pressure of the showerhead, may hinder the operation of the latter. 
     Another limitation, which is inherent to the second previous solution mentioned above, relates to the fact that it does not allow the user to utilize, by means of a simple manual operation during the bath, the pressurized water flow itself, being admitted in the hollow body of the showerhead, for carrying out an intense cleaning of the sieve holes, with the latter being totally freed from the pins of the cleaning means. 
     In all known solutions, having manual or automatic cleaning, the sieve holes present a reduced cross section, which facilitates obstruction and impairs the unclogging thereof, not only by the cleaning pins, but also by using the supply water flow itself, of the showerhead, for cleaning the holes and remove impurities therefrom. In said known solutions, the small sieve holes further facilitate the occurrence of continuous water drops after the showerhead is turned off. 
     SUMMARY OF THE INVENTION 
     Due to the inconveniences cited above and related to the solutions of the state of the art, it is an object of the present invention to provide a showerhead, with a robust and relatively simple construction and which allows an effective and easy unclogging operation to be effected on the sieve holes, either individually or jointly, through a simple manual operation of the user during the bath, or also automatically, by operation of the showerhead itself, with the use of the water flow passing through the sieve holes. 
     The invention further provides a showerhead as cited above, which presents a sieve capable of producing a pleasant bath sensation, with a relatively reduced water flow and with the sieve holes being difficult or even impracticable to be obstructed by the impurities eventually present in the supply water flow of the showerheads. 
     It is a further object of the present invention to provide a showerhead, as mentioned above and which presents a quick and full drainage of the sieve, eliminating the inconvenience of the showerhead dripping for a certain time, after turned off, even when the sieve is positioned rather inclined in relation to a horizontal plane. 
     The present showerhead has an automatic cleaning function, which comprises a phase of washing the sieve holes, upon the initial turning on of the showerhead, with said holes presenting a conveniently widened free cross section, and a phase of cleaning and adjusting the free cross section of said holes, upon the normal operation of the showerhead. 
     Besides the automatic cleaning function, the showerhead also presents a manual cleaning function, which allows the user to carry out, through a simple manual operation during the bath, an intense washing of the sieve holes with a widened cross section, when said holes are completely liberated by the pins of the cleaning element. The present showerhead is of the type which comprises a hollow body provided with an inlet nozzle, to be coupled to a water supply pipe, and with a lower wall defined by a sieve perforated by a plurality of holes. 
     According to the invention, the showerhead further comprises: a cleaning means mounted in the interior of the hollow body, carrying a downwardly projecting plurality of pins and being displaceable between an inoperative position, in which it maintains the pins spaced away from the holes of the sieve, and an operative position, in which each pin is introduced into a respective hole of the sieve, defining at least one, and preferably, a plurality of water outlets with said hole; a driving means, operatively associated with the inlet nozzle and affixed to the cleaning means, maintaining the latter in said inoperative position, while the hydraulic pressure in the interior of the inlet nozzle is inferior to a reference value, and displacing said cleaning means to the operative position, when said hydraulic pressure reaches the reference value; and an impelling means mounted in the interior of the hollow body and displacing the driving means and the cleaning means to the inoperative position, when said hydraulic pressure is inferior to the reference value. 
     The solution proposed by the present invention comprises the provision of a fixed sieve and of a movable cleaning means, but with the latter having its lower pins maintained spaced away from the sieve holes, while the showerhead remains turned off, and during an initial period in which the showerhead is turned on, allowing an initial flow of water to enter into the body of the showerhead and be directed to the sieve holes with a widened cross section, washing the latter, while they stay fully open, without any interference of the pins of the cleaning means. 
     By turning on the showerhead, the hydraulic pressure in its inlet nozzle rises, displacing the cleaning means to the operative position, in which its pins are inserted in the respective holes of the sieve, promoting a second cleaning phase of the latter and regulating the flow of water released by the showerhead, through one or more water outlets formed between each pin and the inner contour of the respective hole of the sieve. 
     The invention further proposes a construction capable of allowing the pins of the cleaning means to be jointly or individually displaced, axially and upwardly, to an inoperative position, in which the sieve holes are cleared off, by actuation of the user, with the showerhead in a full bath operation, so that the pressurized water flow, being admitted in the body of the showerhead, may carry out, with the sieve holes in a full on condition, an intense washing of said holes. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described below, with reference being made to the appended drawings, given by way of example of a possible embodiment of the invention and in which: 
         FIG. 1  represents an upper perspective view of the hollow body of the showerhead; 
         FIG. 2  represents a lower perspective view of the hollow body of a first embodiment of the showerhead, inferiorly closed by a sieve; 
         FIG. 3  represents a diametrically and vertically cut perspective view of the first embodiment of the showerhead in the turned off condition, with the cleaning means in the inoperative position; 
         FIG. 4  represents a diametrically and vertically cut perspective view of the showerhead of  FIG. 3 , but in the fully turned on condition, with the cleaning means in the operative position; 
         FIG. 5  represents a diametrically and vertically cut perspective view of the showerhead of  FIGS. 3 and 4 , in the fully turned on condition and with the cleaning means manually displaced to the inoperative position, allowing the full water flow being admitted in the hollow body of the showerhead to effect an intense operation of washing the sieve holes during the shower bath; 
         FIG. 6  represents a lower perspective view of the hollow body of a second embodiment of the showerhead, with the pins of the cleaning means in the operative position inserted in the interior of the respective sieve holes, with the showerhead in the on condition; 
         FIG. 7  represents a lower perspective view of the hollow body of the second embodiment of the showerhead, with the pins of the cleaning means being displaced to an elevated inoperative position, unblocking the sieve holes, with the showerhead in the off condition; 
         FIG. 8  represents a diametrically and vertically cut perspective view of the showerhead, of the second embodiment of the showerhead in the on condition, with the pins of the cleaning means in an operative position, inside the respective sieve holes; 
         FIG. 8A  represents an enlarged detail of part of  FIG. 8 ; 
         FIG. 9  represents a diametrically and vertically cut perspective view of the showerhead of  FIG. 8 , but in the off condition, with the pins of the cleaning means in an inoperative position, retracted in relation to the respective holes of the sieve; 
         FIG. 10  represents an enlarged perspective view of the pins of the cleaning means; and 
         FIG. 11  represents a plan view of the pin illustrated in  FIG. 10 , when positioned in the interior of a respective hole of the sieve, according to the second embodiment of the invention. 
     
    
    
     DESCRIPTION OF THE INVENTION 
     As already mentioned and illustrated in the appended drawings, the present showerhead comprises a hollow body  10  formed of any adequate material and provided with an inlet nozzle  11 , to be coupled to a water supply pipe (not illustrated), and with a lower wall  12 , defined by a sieve C perforated by a plurality of holes  13 . 
     According to the two illustrated constructions, the hollow body  10  presents a lateral wall  14 , generally cylindrical, but which may be square, rectangular, oval, etc., having a lower edge  14   a , whose sealing, in relation to a peripheral region of the lower wall  12 , is effected by an O′ring  20 , and an upper edge  14   b  incorporating a peripheral region of an upper wall  15 , wherefrom the inlet nozzle  11  projects outwards. 
     The inlet nozzle  11  may have the form of a tubular sleeve which is internally or externally threaded, so as to receive the end of the supply pipe (not illustrated), defining a rigid connection between the latter and the hollow body  10  of the showerhead. 
     In the illustrated constructions, the inlet nozzle  11  defines, internally, the housing for a spherical inner end  18   a  of a tubular connector  18 , whose outer end  18   b  is configured to be threaded to the supply pipe. 
     The inlet nozzle  11  further presents an inner groove  11   a  in the interior of which is housed an O′ring  19 , made of elastomer, in order to guarantee the sealing between the spherical inner end  18   a  and the inlet nozzle  11 . 
     The particular way by which O′ring  19  is maintained in position in the interior of the inlet nozzle  11 , will be described hereinafter. 
     The lower edge  14   a  of the lateral wall  14  presents a thread  14   c , preferably (but not necessarily) external, in which is threaded a ring  30  for fixation of the sieve C in the hollow body  10 . 
     According to the invention, the showerhead further comprises a cleaning means  40  mounted in the interior of the hollow body  10 , carrying a plurality of downwardly projecting pins  41 , the cleaning means  40  being displaceable between an inoperative position ( FIGS. 3, 5, 7 and 9 ), in which it keeps the pins  41  away from the holes  13  of the sieve C, and an operative position, in which each pin  41  is introduced into a respective hole  13  of the sieve C ( FIGS. 4, 6, 8 and 8A ), defining at least one water outlet S, of reduced cross section, with the respective hole  13  in which the pin  41  is introduced. In the illustrated embodiments, the cleaning means  40  comprises a grid  42  guided in the interior of the hollow body  10  of the showerhead, during the displacement of the cleaning means  40 , between its inoperative and operative positions, said grid  42  carrying a plurality of pins  41 , incorporated in said grid  42  in a single piece, or optionally, a plurality de pins  41  mounted in respective windows  42   a  in the grid  42 , so as to be axially displaced in relation to the latter, in the interior of said housings  45 , by a distance slightly superior to the axial extension of each hole  13  of the sieve C. 
     One of the parts defined by the lower face of the cleaning means  40  and the upper face of sieve C may further incorporate a plurality of small eccentric axial projections  44  (see  FIGS. 3, 4, 5, 8, 8A and 9 ), which are seated against the other of said parts, in order to maintain the grid  42  slightly spaced away from the sieve C, when conducted to the operative position. 
     The showerhead further comprises a driving means  50 , operatively associated with the inlet nozzle  11  and affixed to the cleaning means  40 , maintaining the latter in said inoperative position, while the hydraulic pressure in the interior of inlet nozzle  11  is inferior to a reference value, and displacing said cleaning means to the operative position, when said hydraulic pressure reaches the reference value. 
     An impelling means  60  is mounted in the interior of the hollow body  10 , for displacing the driving means  50  and the cleaning means  40  to the inoperative position, when the hydraulic pressure in the interior of inlet nozzle  11  is inferior to said reference value. 
     In the constructive illustrated forms, the hollow body  10  is provided, in the interior of the inlet nozzle  11 , with a conical seat  70 , of tubular shape and preferably threaded in the interior of the inlet nozzle  11 , and which projects downwardly from the upper wall  15  of the hollow body  10  and is also axially aligned with the inlet nozzle  11 . 
     The conical seat  70  presents an outer end  71  open to the interior of the inlet nozzle  11 , and an inner end  72  open to the interior of the hollow body  10 . The outer end  71  of the conical seat  70  has the function of defining the lower axial retention of the O′ring  19 , maintaining the latter pressed between the inlet nozzle  11  and the spherical inner end  18   a  of the tubular connector  18 . In the embodiment illustrated in  FIGS. 3, 4 and 5 , the conical seat  70  is provided with a plurality of inner axial recesses  75 , extending until the inner end  72  of the conical seat  70  and inferiorly open to respective lower radial recesses  76 , also provided in the inner end  72  of the conical seat  70 , in order to allow a restricted fluid communication between the inlet nozzle  11  and the interior of the hollow body  10 , upon start of the showerhead operation. 
     In the embodiment illustrated in  FIGS. 8, 8A and 9 , the conical seat  70  has its lower end  72  configured to define, with the adjacent median portion of the grid  42 , an annular gap which defines a restricted water passage between the inlet nozzle  11  and the interior of the hollow body  10 , upon the start of the showerhead operation, that is, when turned on. 
     The driving means  50  comprises a piston  51  having a base end  51   a  affixed to the cleaning means  40  and a top end  51   b  presenting a median recess  51   c  which may present a inverted slightly conical recess, as illustrated in  FIGS. 3, 4 and 5 , or an inverted frusto-conical deeper recess, to cooperate with the conical seat  70 , in the inoperative position of the cleaning means  40 , as illustrated in  FIGS. 8 and 9 . 
     The piston  51  is axially displaced, in the interior of the hollow body  10 , to displace the cleaning means  40  between its inoperative and operative positions, as a function of the hydraulic pressure in the interior of the inlet nozzle  11 , that is, in the interior of the conical seat  70 , upstream the piston  51 . 
     In the embodiment illustrated in  FIGS. 3, 4 and 5 , the conical seat  70  and the piston  51  are constructed to allow a relatively restricted fluid communication between the inlet nozzle  11  and the interior of the hollow body  10 , when the cleaning means  40  is in the inoperative position, illustrated in  FIG. 3 , and a complete fluid communication between the inlet nozzle  11  and the interior of the hollow body  10 , when the cleaning means  40  is displaced to the operative position illustrated in  FIG. 4 . 
     In the embodiment illustrated in  FIGS. 8 and 9 , the conical seat  70  and the piston  51  are constructed for: eliminating any relevant fluid communication between the inlet nozzle  11  and the interior of the hollow body  10  when the cleaning means  40  is in the inoperative position, illustrated in  FIG. 9 ; a partial fluid communication between the inlet nozzle  11  and the interior of the hollow body  10 , when the cleaning means  40  is slightly downwardly displaced, as a function of the supply hydraulic pressure, allowing that a certain water flow reaches the holes  13  of the sieve C, before they receive the respective pins  41 ; and a full fluid communication between the inlet nozzle  11  and the interior of the hollow body  10 , when the cleaning means  40  is displaced to the operative position illustrated in  FIGS. 8 and 8A , with the pins  41  introduced in the respective holes  13  of the sieve C. 
     Thus, in both embodiments, upon start of the turn-on operation of the showerhead, the pressurization of the inlet nozzle  11  and of the conical seat  70  is made in a progressive way, remaining in values inferior to the reference value and which are insufficient to provoke displacement of the piston  51  and of the cleaning means  40  to the operative position of the latter, but allowing the water to be supplied to the holes  13  of the sieve C while the pressure in the inlet nozzle  11  remains inferior to the reference value. 
     During the time the cleaning means  40  remains in its inoperative position, with the impelling means  60  exerting, against the piston  51 , a force superior to the opposite force produced by the hydraulic pressure in the interior of the conical seat  70 , the water flow entering in the hollow body  10  will pass between the piston  51  and the inner end  72  of the conical seat  70 , more precisely through the inner axial recesses  75  and lower radial recesses  76  of the conical seat  70 , in the embodiment of  FIGS. 1 to 5 , reaching the holes  13  of the sieve C which are found completely free from the pins  41  of the cleaning means  40 . This initial water flow, admitted in the showerhead, carries out the first cleaning phase, washing the holes  13  of the sieve C and dragging, to the outside of the hollow body  10 , any solid impurity that might have been brought by the water supply system. 
     In order to make said first cleaning phase be a washing phase for the holes  13  of the sieve C, said holes present a cross section area, generally (but not necessarily) circular, larger than that required in the project, for each water outlet of the sieve C with the normal operation of the showerhead. 
     Thus, when the pins  41  are introduced into the holes  13 , the free cross section area of the latter becomes sufficient and adequate to form the desired water flow to be released by the showerhead. The debris, if existing in the water flow admitted in the hollow body  10 , are removed by the initial washing flow and drained through the holes  13  of the sieve C, which holes are dimensioned with a diameter much larger than that usually employed, minimizing the retention of particulate material in said holes  13 . 
     With the continuous turning-on of the showerhead, the hydraulic pressure in the interior of the inlet nozzle  11  and of the conical seat  70  is elevated, until reaching the reference value, from which the force exerted by the impelling means  60  is overcome, allowing the piston  51  to be displaced toward the sieve C, dragging the cleaning means  40  to the operative position, in which the pins  41  are introduced in the respective holes  13 , diminishing the free cross section of the latter to an area dimensioned so as to allow the adequate water discharge from the sieve C. 
     In the embodiment of  FIGS. 1 to 5 , the pins  41  are loosely introduced in the holes  13  of the sieve C, defining a single water outlet S, of annular shape, in the gap defined between the pin  41  and the inner wall of the respective hole  13 . In this embodiment, the penetration of the pins  41  in the holes  13  also has the function of promoting a second cleaning phase of the sieve C, clearing the holes  13 . Any residue penetrating in the interior of the hollow body  10  during its normal operation and being larger than the annular radial gap existing between each pin  41  and the respective hole  13 , will be retained in the upper portion of the hole  13 , without provoking the flow distortions observed in the prior art systems. 
     In the embodiment of  FIGS. 6 to 11 , the holes  13  of the sieve C have diameters even larger than those of the first embodiment, presenting an inverted slightly frusto-conical shape, each pin  41  presenting a body  41   a  with a correspondent frusto-conical shape so as to be fitted, with no gap, in the interior of a respective hole  13  of the sieve C, said body  41   a  carrying an upper neck  41   b , to be mounted to the grid  42  of the cleaning means  40 . 
     In said second embodiment, the body  41   a  of the pin  41  is provided with a plurality of outer axial grooves  41   c , extended throughout the whole height of the body  41   a  and which define, each one, with the inner wall of the respective hole  13  of the sieve C, a water outlet S of the sieve C. Thus, after receiving the respective pin  41 , each hole  13  of the sieve C is transformed into a plurality of water outlets S, increasing the sensation of abundant water during the bath, with a relatively reduced consumption of water in relation to the conventional solutions and even in relation to the solution defined in the first embodiment of the present invention. 
     In the referred second embodiment, each pin  41  has its tubular-shaped neck  41   b  fitted, with a small gap, through a respective window  42   a  provided in the grid  42  and incorporating a widened end  41   d  to be seated in a region of the upper face of the grid  42 , defined around each window  42   a . Thus, each pin  41  can be manually and individually upwardly displaced by the user of the showerhead, during the shower bath, in order to completely liberate the respective hole  13  of the sieve C, promoting a complete washing, not only of the hole  13  itself, but also of all the outer axial grooves  41   c  of the body  41   a  of the pin  41 . 
     In order to guarantee that the pins  41  are adequately positioned in the interior of the respective holes  13  of the sieve C, upon displacement of the cleaning means  40  from the inoperative position to the operative position, mainly when the sieve C is positioned in an inclined plane (not horizontal), each pin  41  may incorporate at least one lower guide means which, in the case of the second embodiment illustrated in  FIGS. 6 to 11 , takes the form of a plurality of lower peripheral axial projections of the body  41   a  of the pin  41 . The lower guide means  41   e  should present an axial length sufficient to remain partially fitted in the interior of the respective hole  13  of the sieve C when the pin  41  is individually, or jointly with the other pins  41 , upwardly displaced to the inoperative position of the cleaning means  40 . 
     At the end of the bath, after the showerhead is turned off, it occurs the depressurization of the conical seat and the displacement of the piston  51  and of the cleaning means  40 , by action of the impelling means  60 , to the inoperative position in which the holes  13  are freed from the pins  41 , being open to receive a new washing when the showerhead is turned on again, or upon a manual displacement, either jointly or individually, of the pins  41  to the inoperative position of the cleaning means  40 . 
     Still according to the illustrated embodiments, the impelling means  60  comprises a helical spring  61  having an end seated on the sieve C and an opposite end seated against one of the parts defined by the piston  51  and by the cleaning means  40 . In a preferred way, the piston  51  presents a tubular shape, with its base end  51   a  open and turned to the sieve C. With this construction, the opposite end of the helical spring  61  is fitted in the interior of the piston  51  and seated under the top end  51   b.    
     In the embodiment illustrated in  FIGS. 1 to 5 , the showerhead presents an optional construction, according to which the lower wall  12  incorporates a central tubular nozzle  16 , having an outer end  16   a , provided, internally, with a small annular flange  17  which defines a stop means B, and with an inner end  16   b  which projects to the interior of the body of the showerhead, through a tubular wall  16   c , and against which is seated the top end  51   b  of the piston  51  when the cleaning means  40  is conducted to the operative position, with the showerhead under full operation, in the turned on condition. In said condition, the base end of the piston  51   a  is positioned around the tubular wall  16   c  of the central tubular nozzle  16 . 
     In the interior of the central tubular nozzle  16  is slidingly mounted a plunger  80 , preferably in the form of a cup  81 , having a lateral wall  82 , telescopically sliding in the interior of the central tubular nozzle  16 , and a lower end wall  83  against which is seated an adjacent end of the impelling means  60  which, in the example illustrated, is defined by the helical spring  61 . The lateral wall  82  of the cup  81  is provided with at least one peripheral groove  84 , in which is lodged a sealing ring  90  in O′ring form, which is radially and slidingly pressed against the tubular wall  16   c  of the central tubular nozzle  16 . 
     Such constructive variant allows the user to achieve, during the bath, and intense additional washing of the holes  13  of the sieve C. Therefore, the user only needs to promote a simple axial and ascending manual displacement of the plunger  80 , in the interior of the central tubular nozzle  16 , from an inactive position, in which it has its lower end wall  83  seated against the small annular flange  17 , by actuation of the impelling means  60 , to an active position, in which the lateral wall  82  of the plunger  80  is seated against the top end  51   b  of the piston  51  and displacing axially upwards the cleaning means  40  to its inoperative position, with its lower pins  41  being displaced to the outside of the holes  13  of the sieve C, allowing the pressurized water flow being admitted in the body of the showerhead to carry out an intense washing of said holes  13  of the sieve C, in which said holes  13  are in a full on condition and the showerhead is in a full bath operation. 
     The user then releases the manual force exerted on the plunger  80 , for allowing the water pressure to push the cleaning means back to its operative position and the impelling means  60  to return the plunger  80  to its inactive position. 
     The user may carry out several operations of pressing and releasing the plunger  80 , in order to provide multiple washing operations of the holes  13  of the sieve C during the shower bath. 
     As mentioned above in the illustrated constructions, the lower wall  12 , which defines the sieve C, presents the central tubular nozzle  16  for housing the plunger  80 . However, it should be understood that the lower wall  12  may be closed in the region of the central tubular nozzle which, in this case, is suppressed from the showerhead, the same occurring with the plunger  80 . In said basic constructive option, the showerhead does not allow the user to carry out the operations of washing the sieve during the bath, that is, during operation of the showerhead. 
     It should be understood that the construction illustrated in  FIGS. 6 to 11  may also present the same elements described in relation to the embodiment of  FIGS. 1 to 5 , so as to allow the user to displace all the pins  41  jointly, by displacing the same plunger mounted in an identical central tubular nozzle provided in the sieve C. In the embodiment illustrated in  FIGS. 6 to 11 , the central tubular nozzle  16  is found closed, internally, by a removable wall and, externally, by a cap T. 
     While only two embodiments of the invention have been illustrated herein, it should be understood that modifications in the form and arrangement of the component parts can be made, without departing from the inventive concept defined in the claims that accompany the present disclosure.