Field of the Invention

The present invention relates to the technical field of cleaning equipment, and in particular to a wet mopping device capable of moping and cleaning a floor to be cleaned, and a wet-and-dry cleaning head for a floor cleaning equipment. The present invention also relates to a drainer for use on the above-mentioned wet mopping device and wet-and-dry cleaning head.

Background of the Invention

In daily life, vacuum cleaners are generally used for sucking particulate matter such as dust on floors to be cleaned, and are particularly suitable for cleaning rough floors, for example, for cleaning indoor carpets, wooden floors, etc. For the cleaning of smooth floors, such as floor tiles and ceramic tiles, cleaning mops are generally used to wipe the smooth floors with wet mop cloth to remove stains from the surface of the smooth floors. Such a cleaning approach inevitably requires a user to replace the cleaning tool multiple times to realize the cleaning operation of the surface to be cleaned, which is cumbersome to operate.

The Chinese invention patent application with the publication number of CN107072460A discloses a floor cleaning device comprising a liquid containing system. The liquid containing system possesses an outlet having a plurality of openings to allow liquid to be drawn by a capillary force when a mop base such as mop cloth is mounted against the plurality of openings. The liquid containing system is substantially closed after filling except for the plurality of openings. Since the mop cloth is in direct contact with the plurality of openings of the liquid containing system, the water in the liquid containing system can be directly applied to the mop cloth by means of a capillary suction force. As such, water is drawn onto the mop cloth quickly and mop is very wet. When the mop cloth is applied to operate on a floor to be cleaned, substantial water stains are susceptible of remaining on the floor, and the cleaning result is not ideal. In addition, in order to solve the problems of the mop cloth’s water drawing speed and water content, the above-mentioned patent imposes high requirements on the material and size of the mop base and the diameter of the openings of the liquid containing system. This results in substantially severe processing precision and requirements regarding the manufacturing of various parts of the mop, thus great difficulties in manufacturing and high costs.

Summary of the Invention

In order to solve the above-mentioned technical problems, a first objective of the present invention is to provide a drainer having good capability of water conduction; a second objective of the present invention is to provide a wet mopping device that is provided with the drainer which is convenient in mounting and dismounting; a third objective of the present invention is to provide a wet-and-dry cleaning head for a floor cleaning equipment that is provided with the drainer which is convenient in mounting and dismounting.

In order to achieve the above-mentioned first objective of the present invention, the present invention adopts the following technical solution:

A drainer, comprising:

- a housing, provided with a plurality of water discharge holes at the bottom, at least one water inlet at the top, and defining a cavity inside; the water inlet, cavity, and water discharge holes being in communication sequentially;

- a plurality of absorbent cores, mounted inside the cavity of the housing, each of which being partially exposed from a corresponding water discharge hole, so that the absorbent core can guide water entering the cavity to the exterior of the housing through the water discharge hole.

In the above-mentioned technical solution, preferably, the housing is integrally formed, the absorbent cores being permanently limited inside the housing.

In the above-mentioned technical solution, preferably, the housing is formed by at least two parts separable from each other, so that the absorbent cores are replaceable.

In the above-mentioned technical solution, preferably, a water guiding member capable of guiding water to flow from one side to another is provided at an inner bottom face of the cavity; each of the absorbent cores is in contact with the water guiding member, so that water flowing onto the water guiding member can be guided to the absorbent cores.

In the above-mentioned technical solution, preferably, the water guiding member and the plurality of absorbent cores are integrally formed.

In the above-mentioned technical solution, preferably, a partition located above the absorbent cores is provided inside the cavity, the partition being provided with a plurality of small through holes via which water flowing into the cavity flows to the absorbent cores below.

In the above-mentioned technical solution, preferably, an upper surface of the partition is an oblique face that inclines downwards from near the water inlet to away from the water inlet.

In the above-mentioned technical solution, preferably, an inner wall face of the housing is provided with several positioning pins on which the water guiding member is sleeved.

In the above-mentioned technical solution, preferably, an inner wall face of the housing is provided with several plots that are located above the absorbent cores, each plot facing one water discharge hole, the absorbent cores being tightly pressed inside the water discharge holes by means of the plots.

In order to achieve the above-mentioned second objective of the present invention, the present invention adopts the following technical solution: a wet mopping device comprising a base plate for mounting a mop cloth and a water supply tank located above the base plate and used for supplying water to the mop cloth, the bottom of the water supply tank being provided with a water outlet; the base plate is provided with a drainer according to any one of the above-mentioned technical solutions, the water inlet being in communication with the water outlet, the housing of the drainer being at least partially separable from the base plate.

In the above-mentioned technical solution, preferably, the base plate is provided with a venting pipe connecting the cavity of the drainer with the water supply tank, the venting pipe protruding from an upper surface of the base plate and up to above the maximum fill level of water in the water supply tank, so as to vent the air existing in the cavity when the water enters the cavity via the water outlet. The housing of the drainer is provided with a connecting port connected with the venting pipe.

In the above-mentioned technical solution, preferably, an upper half of the housing is integrally formed with the base plate, and a lower half of the housing is detachably connected to the upper half.

In the above-mentioned technical solution, preferably, the housing of the drainer is integrally separable from the base plate.

In the above-mentioned technical solution, preferably, the base plate is provided with a groove for receiving the housing.

In the above-mentioned technical solution, preferably, the base plate and the water supply tank are integrally fixed or integrally formed.

In the above technical solution, preferably, the top of the water supply tank is provided with a water filling port, a tank cap being arranged at the water filling port and comprising an air inlet open towards the interior of the water supply tank and an air opening open towards the outside of the water supply tank, the tank cap comprises a chicane shape formed by at least one baffle and forming an air inlet channel extending inside the tank cap from the air inlet to the air opening. The chicane shape constitutes an obstacle on the way from the interior of the water supply tank to the outside, so that water cannot leak outwards when the water tank is tilted.

In the above technical solution, preferably, the tank cap comprises a cover part and a lining part that is mounted to the cover part.

In the above technical solution, preferably, the cover part comprises said chicane shape.

In the above technical solution, preferably, at least one of the baffles is hollowed to define an intermediate air opening in the air inlet channel.

In the above technical solution, preferably, the water outlet is provided with a valve for opening and closing the water outlet, and the water supply tank is externally provided with an action member which is operable by a user, the action member and the valve being disposed in a manner allowing the transmission of motion such that the user is able to open or close the water outlet by operating the action member.

In a preferred embodiment, a cam surface is formed at a top portion of the valve plug to lock the drain valve in the closed or open position. To close the valve, the end of a lever arm of the action member should be forced to pass through the cam surface to push the valve plug in an axial direction against a spring force that tends to urge the valve plug upwards. Conversely, to open the valve, the end of the lever arm of the action member should be forced to pass through a protrusion.

In a preferred embodiment, the valve is provided with two sealings, a lower one formed by an O-ring for radial sealing and an upper one formed by a washer with axial lip for axial sealing, in order to reduce the effort needed to operate the plug of the valve.

In order to achieve the above-mentioned third objective of the present invention, the present invention adopts the following technical solution: a wet-and-dry cleaning head for a floor cleaning equipment, comprising:

- a cleaning head body provided with at least one dust suction port at the bottom;

- a base plate used for mounting a mop cloth; - a water supply tank located above the base plate and used for supplying water to the mop cloth, the bottom of the water supply tank being provided with a water outlet; the base plate is provided with a drainer according to any one of the above-mentioned technical solutions, the water inlet at the top of the housing being in communication with the water outlet, the housing of the drainer being at least partially separable from the base plate.

In the above-mentioned technical solution, preferably, the base plate is located at the bottom of the cleaning head body, and the water supply tank is detachably mounted at the top of the cleaning head body.

In the above-mentioned technical solution, preferably, the base plate is detachably mounted at the bottom of the cleaning head body.

In the above-mentioned technical solution, preferably, the base plate and the water supply tank are integrally fixed or integrally formed, and are detachably mounted to the cleaning head body.

In a preferred embodiment, the base plate is provided with at least one locking element which cooperates with a corresponding locker arranged on the cleaning head body so as to lock the base plate with the cleaning head body. The locking element is for example a hook. The base plate is preferably provided with two locking elements and more preferably with four. The locking elements may be integrally formed with the base plate or attached thereto.

With the drainer of the present invention, by providing absorbent cores that are inside the cavity of the housing and partially exposed therefrom at the water discharge holes of the housing, the drainer is enabled to guide water entering the cavity of the drainer to the exterior of the housing thanks to the good absorbent capacity of the absorbent cores. As a result, when the drainer of the present invention is applied to humidify a mop cloth, the water content on the mop cloth is appropriate and uniform, without leaving many water stains on a floor to be cleaned, thereby improving the effect of floor cleaning. At least part of the drainer being separable with the base plate of the wet mopping device, replacement of the drainer and components inside it by a user is facilitated, thereby facilitating the cleaning and maintenance of the drainer.

Description of the Drawings

Fig. 1 is a schematic perspective view of a wet-and-dry cleaning head of the present invention; Fig. 2 is a schematic exploded view of a wet-and-dry cleaning head of the present invention;

Fig. 3 is a schematic top view of a wet mopping device of the present invention;

Fig. 4 is a first schematic cross-sectional structural view of a wet mopping device of the present invention (after a user operates an action member in one direction, a valve closes the water outlet on the base plate of the water supply tank);

Fig. 5 is second schematic cross-sectional structural view of a wet mopping device of the present invention (after a user operates the action member in another direction, the valve opens the water outlet on the base plate of the water supply tank); Fig. 6 is a schematic exploded view of a drainer of the present invention;

Fig. 7 is a schematic partial enlarged view of the detail A in Fig. 5;

Fig. 8 is a schematic bottom view of an upper cover of a drainer of the present invention;

Fig. 9 is a schematic top view of the remaining part of a drainer of the present invention after the upper cover is removed; Fig. 10 is a schematic cross-sectional structural view of a drainer of the present invention;

Fig. 1 1 is a schematic perspective view of another embodiment of the wet mopping device of the present invention;

Fig. 12 is a cross-sectional structural view of the wet mopping device as shown in Fig.1 1 ;

Fig. 13 is a schematic exploded view of the water filing part of the wet mopping device as shown in Fig.1 1 ;

Fig. 14 is a schematic side view of the wet mopping device as shown in Fig.1 1. wherein: 1 1. Cleaning head body; 1 1 1. Dust suction port; 1 12. Suction passage; 1 13. Rotary connector;

12. Wet mopping device; 121 . Base plate; 122. Water supply tank; 123. Groove; 124. Water outlet; 125. Air inlet; 126. Action member; 127. Valve; 128. Plug; 129. Spring; 130. Mounting hole; 131. Check valve; 132. Rotating shaft; 133. Sealing ring; 134. Water filling port; 135. Cover; 136. Cover part; 138. Lining part. 14. Drainer; 141. Housing; 142. Upper cover; 143. Lower cover; 144; Water inlet; 145. Cavity; 146. Partition; 147. Through hole; 140. Absorbent member; 148. Absorbent core; 149. Water guiding member; 150. Water discharge hole; 151. Plot; 152. Positioning pin; 153. First positioning hole; 154. Second positioning hole; 155. Positioning slot; 156. Small hole.

22. Locking element; 24. Venting pipe; 26. Internal wall; 32. Fixing hole; 33. Screw hole; 36. Chicane shape; 361. Inner skirt; 362. Ribs; 363. intermediate air opening; 364. first notch; 37. Outer skirt; 373. block; 374. second notch; 38. Air inlet; 41 . Cam surface; 42. First edge; 43. Protrusion; 44. Second edge; 34. Upper sealing ring; 50. Lever arm.

Detailed Description of the Invention

The technical contents, structural features, achieved objectives and effects of the present invention will be described in detail below with reference to embodiments and the accompanying drawings. The positional relationships of upper, lower, left, right, front, and rear described in the present embodiments correspond to the respective positional relationships shown in Fig. 1 , respectively. The floor cleaning equipment described is an equipment used for performing dust suction and cleaning on a floor to be cleaned. It can be for example a wet-and-dry vacuum cleaner, or a floor scrubber.

As shown in Fig. 1 and Fig. 2, a wet-and-dry cleaning head comprises a cleaning head body 1 1 capable of moving on a floor to be cleaned, a rotary connector 1 13 connected to the cleaning head body 1 1 , a suction passage 1 12, and a wet mopping device 12 fixedly mounted to the cleaning head body 1 1 . In the wet-and-dry cleaning head, a part of the suction passage 1 12 is received inside the cleaning head body 1 1 , and another part of it is provided on the rotary connector 1 13. The cleaning head body 1 1 is provided at the bottom with two dust suction ports 1 1 1 that are opposite each other in the front-rear direction. When the wet-and-dry cleaning head is applied to be used on a floor cleaning equipment, it is connected with a main body portion of the floor cleaning equipment via the rotary connector 1 13, for example, to a suction unit of the floor cleaning equipment by means of a hard tube or a hose. The suction passage 1 12 is capable of sucking in particulate matter such as dust on the floor to be cleaned through the dust suction ports 1 1 1 by means of a suction force of the suction unit. Of course, it is also possible to provide only one dust suction port 1 1 1 at a front portion of the cleaning head body 1 1 , in front of the wet mopping device 12. Thus, a function of first dusting and then mopping can be realized.

As shown in Fig. 3 and Fig. 4, the wet mopping device 12 comprises a base plate 121 used for mounting a mop cloth and a water supply tank 122. A lower portion of the water supply tank 122 is of an opening structure. The base plate 121 is fixedly mounted at the lower portion of the water supply tank 122 and closes the opening of the lower portion of the water supply tank 122, so that the water supply tank 122 and the base plate 121 enclose and define a water storage chamber. Of course, to facilitate manufacturing by injection molding, the base plate 121 and the water supply tank 122 can also be integrally formed.

To facilitate the adding of cleaning water by a user, a wet mopping device 12 is detachably mounted to the cleaning head body 1 1 . Specifically, the water supply tank 122 has two tank portions that are opposite each other in the left-right direction, and a connection portion that connects the two tank portions. The connection portion is of a hollow structure and integrally formed with the two tank portions. The space between the two tank portions forms a snap groove. The cleaning head body 1 1 has a snap-in portion adapted to the snap groove. When the wet mopping device 12 is mounted to the cleaning head body 1 1 , the snap-in portion of the cleaning head body 1 1 is snapped in the snap groove of the wet mopping device 12, and the water supply tank 122 is located at the top of the cleaning head body 1 1. An upper portion of the water supply tank 122 is provided with a water filing port 134, and a cover 135 is provided at the water filing port 134.

Of course, to facilitate the mounting of a mop cloth, the wet mopping device 12 does not need to be completely detached from the cleaning head body 1 1. It is sufficient to fix the water supply tank 122 to the cleaning head body 1 1 , and detachably provide the base plate 121 at the bottom of the water supply tank 122. Specifically, the base plate 121 is connected to the water supply tank 122 in a snap-fit manner, with a lower edge of a side wall plate of the water supply tank 122 constituting a connection portion and the base plate 121 being provided with a circumferentially arranged connection groove adapted to the lower edge of the side wall plate of the water supply tank 122, and a waterproof sealing strip being provided in the connection groove.

The base plate 121 is provided with a water outlet 124. A drainer 14 that communicates with the water outlet 124 is mounted to the base plate 121 . When a mop cloth is mounted at the lower portion of the base plate 121 , the mop cloth covers the outer side of the drainer 14. Cleaning water in the water storage chamber can be guided to the mop cloth via the drainer 14, so as to humidify the mop cloth.

To facilitate the cleaning water in the water storage chamber entering the drainer 14 so as to be guided to the mop cloth, the water supply tank 122 is provided with an air inlet 125 that puts the external environment and the internal water storage chamber in communication. The air inlet 125 is provided on the cover 135. A check valve 131 is mounted at the air inlet 125. The check valve 131 only allows outside air to enter the water supply tank 122 from the outside, and does not allow air and/or cleaning water in the water supply tank 122 to escape from the interior of the water supply tank 122 into the external environment. As a result, even if the water supply tank 122 is in an upside-down state, the cleaning water inside the water supply tank 122 cannot leak to the floor to be cleaned through the air inlet 125, effectively preventing the drawback of making the floor dirty again when a user replaces the cleaning water.

Of course, the water supply tank 122 can be of a fully closed structure, i.e. , a structure without the air inlet 125. Cleaning water in the water storage chamber is guided to the mop cloth so as to humidify it only by means of the capillary effect of the drainer 14.

To prevent the water in the water supply tank 122 from being continuously guided to the mop cloth by the drainer 14 after finishing a mopping operation, which results in an excessive water content on the mop cloth and thus leaving a large area of water stain on the floor to be cleaned, a valve 127 for opening and closing the water outlet 124 is mounted at the water outlet 124, as shown in Fig. 4 and Fig. 5. An action member 126, operable by a user and drivingly connected with the valve 127, is provided at an upper portion of the water supply tank 122. In use, by operating the action member 126, the user drives the valve 127 to perform an action so as to open or close the water outlet 124 on the base plate 121.

Specifically, the water supply tank 122 is provided with a mounting hole 130. The valve 127 comprises a plug 128 and a spring 129 mounted inside the mounting hole 130. One end of the spring 129 is connected to the plug 128 and the other end of it is connected inside the mounting hole 130. The plug 128 is provided with a sealing ring 133 at a lower end. The action member 126 is a button member, one end of which is mounted to the water supply tank 122 by means of a rotating shaft 132, and the other end constitutes a trigger portion for a user to press or step on. An upper end of the plug 128 abuts against the button member. Of course, the action member 126 is not limited to the above-described button-type rotating member. It can also be a movable member. The structure of the valve 127 is not limited to the above-described plug that moves in the vertical direction either. It can also be a cover plate that moves in the horizontal direction. For example, the movable member is fixedly connected to the cover plate. In use, by operating the movable member, the user drives the cover plate to move in the horizontal direction, so that the cover plate and the water outlet 124 are offset from each other or face each other, so as to open or close the water outlet 124.

The structural composition and application of the drainer 14 will be described specifically in reference to Fig. 2 and Fig. 4 to Fig. 10. As shown in Fig. 2, the drainer 14 is mounted to the lower portion of the base plate 121. With reference to Fig. 4 and Fig. 5, the lower portion of the base plate 121 is provided with a groove 123. The drainer 14 is received in the groove 123. A bottom edge of the drainer 14 is substantially flush with a bottom surface of the base plate 121 . As a result, when a mop cloth is mounted to the base plate 121 , the mop cloth will not appear to be rugged, facilitating tight engagement between the mop cloth and the floor to be cleaned, and improving the mopping result.

As shown in Fig. 6, the drainer 14 comprises a housing 141 , a partition 146, and an absorbent member 140 comprising absorbent cores 148. The housing 141 is formed by an upper cover 142 and a lower cover 143 fastened with each other. With reference to Fig. 10, a cavity 145 is enclosed between the upper cover 142 and the lower cover 143. The partition 146 and the absorbent cores 148 are all located in the cavity 145. The partition 146 is located above the absorbent cores 148. The absorbent cores 148 are made of a material with good absorbent property, for example, water-absorbent resin, cellulose, polyacrylamide, or degreased cotton, sponge, silicone, etc.

In order to tightly fix the partition 146 and the absorbent cores 148 in the cavity 145 by the upper cover 142 and the lower cover 143 after being fastened with each other, with reference to Fig. 8, the upper cover 142 is provided, along the direction of its length, with a plurality of positioning slots 155 and a plurality of plots 151 extending downwards. The plurality of plots 151 and the plurality of positioning slots 155 are provided one adjacent to another. That is to say, one plot 151 is provided between every two positioning slots 155. The lower cover 143 is provided, along the direction of its length, with water discharge holes 150 for inserting the plurality of plots 151 and a plurality of positioning pins 152 adapted to the plurality of positioning slots 155. The plurality of water discharge holes 150 and the plurality of positioning pins 152 are provided one adjacent with another. That is to say, one water discharge hole 150 is provided between every two positioning pins 152. The partition 146 is provided, along the direction of its length, with first positioning holes 153 for being traversed by the plurality of positioning pins 152 and a plurality of through holes 147 for being traversed by the plurality of plots 151. The plurality of first positioning holes 153 and the plurality of through holes 147 are provided one adjacent with another. That is to say, one through hole 147 is provided between every two first positioning holes 153. The partition 146 is further provided with a plurality of small through holes 156 for cleaning water to flow through the partition 146. Each small hole 156 is integrally formed with the corresponding first positioning hole 153. The absorbent member 140 is provided, along the direction of its length, with second positioning holes 154 for being traversed by the plurality of positioning pins 152.

With reference to Fig. 6, Fig. 7, and Fig. 9, when the absorbent cores 148 and the partition 146 are fitted in the housing 141 , the positioning pins 152 on the lower cover 143 traverse, sequentially, the second positioning holes 155 on the absorbent member 140 and the first positioning holes 153 on the partition 146, and finally are inserted inside the positioning slots 155 on the upper cover 142. At the same time, the plurality of plots 151 on the upper cover 142 traverse the plurality of through holes 147 on the partition 146 and are inserted inside the plurality of water discharge holes 150 on the lower cover 143, in the course of which, the absorbent cores 148are tightly pressed inside the water discharge holes 150 by the positioning plots 151 on the upper cover 142, and are partially exposed outside the water discharge holes 150.

The upper cover 142 is provided with a water inlet 144 that communicates with the cavity 145. With reference to Fig. 4 and Fig. 5, when the drainer 14 is mounted at the lower portion of the base plate 121 , the water inlet 144 and the water outlet 124 on the base plate 121 are in communication, and the water inlet 144 of the drainer 14, the cavity 145, and the water discharge holes 150 communicate with each other sequentially. The absorbent core 148 is able to guide cleaning water flowing into the cavity 145 to the outside of the housing 141 via the water discharge holes 150, i.e., to the mop cloth below it, so as to humidify the mop cloth.

In the above-described structure, the housing 141 of the drainer 14 is a separable structure with the upper cover 142 and the lower cover 143 being detachably connected. Of course, to facilitate manufacturing, the housing 142 of the drainer 141 can also be designed to be an integral structure with a cavity 145 enclosed inside, and the absorbent core 148 being permanently limited in the housing 141 . However, as such, when any component inside the drainer 14 is damaged (for example, when problems such as clogging, cracks, and aging occur to the absorbent cores 148), a user needs to replace the entire drainer 14. To enable the user to selectively replace a component in the drainer 14 according to the actual situation of utilization, and mainly for facilitating the replacement of the absorbent core 148 by the user, the housing 141 is best designed to be a separable structure, which is not limited to a two-part structure with an upper cover and a lower cover, and can also be formed by multiple parts, for example, a drainer housing formed by an upper shell, a middle frame, and a lower shell, with the absorbent cores 148 fixed to the middle frame.

With reference to Figure 2, the drainer 14 can be detachably mounted at the lower portion of the base plate 121 . That is to say, the outer contour of the drainer 14 is adapted to the groove 123 on the base plate 121 in a snap-fit connection manner. The upper cover 142 of the drainer 14 can also be fixed to the base plate 121 , with the rest of the drainer 14 such as the lower cover being designed to be removable. As cleaning water entering the drainer 14 will generally fill up the cavity 145 before flowing to the absorbent cores 148 through the small holes 156 on the partition 146, in order to facilitate the absorption of the cleaning water inside the cavity 145 by the absorbent core 148, a water guiding member 149 is deposited at the inner bottom face of the cavity 145. The water guiding member 149 is in contact with the absorbent core 148. The water guiding member 149 also possess a good absorbent property, and is integrally formed with the absorbent core 148 and capable of guiding cleaning water to the absorbent cores 148.

In the above-described structure, the absorbent member 140 is of a one-piece structure, and the water guiding member 149 is integrally formed with the absorbent cores 148. Of course, to facilitate the mounting and replacement of a part of the absorbent core 148, the absorbent core 148 can also be a separable structure. That is to say, a plurality of absorbent cores 148 can be provided. The water guiding member 149 connects the plurality of absorbent cores 148 together. The water guiding member 149 is sleeved to the plurality of positioning pins 152 on the inner wall face of the housing 141. Each absorbent core 148 is in contact with the water guiding member 149, so that cleaning water flowing onto the water guiding member 149 can be guided onto the absorbent cores 148.

As the upper cover 142 is provided with only one water inlet 144, cleaning water entering the drainer 14 via the water inlet 144 will flow from near the water inlet 144 towards away from the water inlet 144. Thus, the water flow arriving at the absorbent cores 148 is not uniform, and the cleaning water ultimately flowing out of the various water discharge holes 150 is not uniform in time, resulting in the mop cloth being partially humidified and partially not humidified. To prevent this situation, it is preferable that an upper surface of the partition is designed as an oblique face, that is to say, inclined downwards from near the water inlet 144 to away from the water inlet 144, so that cleaning water in the drainer 14 flows more slowly when near the water inlet 144 and more quickly when away from the water inlet 144. The overall effect achieved is that the water output rates of the various water discharge holes 150 of the drainer 14 are substantially identical, and the mop cloth is humidified more uniformly with a better humidification result. Of course, other than designing the upper surface of the partition 146 as an oblique face, it is also possible to provide a plurality of water inlets 144 on the upper cover 142 along the direction of its length, which can also make the water output rates of the various water discharge holes 150 of the drainer 14 identical.

Fig. 1 1 to Fig. 14 illustrate another embodiment of the wet mopping device 12 which includes several other aspects of the invention. It should be understood that these aspects may also be applied to the above described embodiment or combined with above described features to constitute new embodiments. In Figs. 1 1-14, same reference numbers are used to designate the identical or similar parts to the embodiment shown in Figs. 1-10.

As shown in Fig. 1 1 , the wet mopping device 12 comprises a base plate 121 and a water supply tank 122, which are similar to those shown in Fig. 2. Two locking elements 22 are provided on each of the front and rear borders of the base plate 121. In the illustrated embodiment, each locking element 22 is in the form of a hook having a recess 221 facing the center of the base plate 121 . The cleaning head body 1 1 is provided with corresponding lockers respectively located on the rear surface of the front suction part and the front surface of the rear suction part (not shown in the figures). When the wet mopping device 12 is mounted to the cleaning head body 1 1 , the locker arranged on the cleaning head body 1 1 are snapped in the recess of the locking element 22 provided on the base plate 121. This cooperation helps to ensure the fastening of the wet mopping device 12 to the cleaning head body 1 1 , in addition or in alternative to the snap fit created by the snap groove formed by the water tanks and the snap-in portion of the cleaning head body 1 1 . Moreover, the locking elements 22 also avoids that the mop cloth overlays completely the base plate 121.

As shown in Fig. 12, the base plate 121 is provided a venting pipe 24 protruding from the upper surface of the base plate 121 to above the maximum filing lever of the water supply tank 122. The housing 141 of the drainer 14 is provided with a connecting port (not shown) connected with the venting pipe 24. Thus, the venting pipe 24 connects the cavity 145 formed inside the base plate drainer 14 with the water supply tank 122. As shown in figures 4 and 5, the base plate 121 only has one water outlet 124 through which water exits the water supply tank 122 and enters the cavity 145 of the drainer 14. It could be difficult for the air trapped in the cavity 145 to get out from the water outlet 124 and the filling of the cavity 145 can thus be obstructed. The venting pipe 24 allows to vent the air existing in the cavity 145 when filling the cavity 145 and thus facilitates the filling.

Also as shown in Fig. 12, the base plate 121 is provided with at least one internal wall 26, in the form of a longitudinal projection protruding from the upper surface to the inside of the cavity 145. The internal wall 26 occupies a part of the volume of the cavity 145 and thus reduces the volume of the cavity 145 that is occupied by water. Therefore, when the valve 127 is actuated to its open position, water can fill the cavity 145 more quickly and moisten the mop more quickly as well. In other words, the time response is decreased between the time the valve 127 is manually actuated and the time when the mop is moistened by water flowing from the liquid discharge holes 150. The quantity and the location of the internal walls 26 can be modified according to actual need. In addition, the internal walls 26 also serve as reinforcing elements of the base plate 121. It can be seen from Fig. 12 that the drain valve 127 is provided with a lower sealing 133 realized by an O-ring for radial sealing and an upper sealing 34 realized by a washer with axial lip for axial sealing, in order to reduce the effort needed to operate the plug 128 of the valve 127. In the embodiment illustrated on Fig. 12, the valve 127 is entirely housed in the mounting hole 130. The lower sealing 133 and the upper sealing 34 both locate between the mounting hole 130 and the plug 128 of the valve 127.

Different from the previous embodiments shown in figures 1 to 10, in the embodiment as shown in figures 1 1 to 14, the tank cap 135 does not comprise an air inlet orifice that is visible from outside or a check valve but defines an air inlet channel extending between an air inlet 38 open towards the interior of the water supply tank 122 and an air opening 364 open towards the outside of the water supply tank 122. The air inlet channel is formed by a chicane shape 36 formed in the tank cap 135. The tank cap 135 comprises a cover part 136 and a lining part 138 that is mounted to the cover part 136. The chicane shape is formed on the top surface of the cover part 136 and protruding downwardly therefrom. In the illustrated embodiment, the chicane shape 36 comprises an inner skirt 361 forming a substantially rectangular contour and ribs 362 linking a screw hole 33 with the inner skirt 361. The lining part 138 is mounted to the bottom of the cover part 136 and comprises a plate provided with an orifice as an air inlet 38 and an outer skirt 37 protruding upwards from the plate and surrounding the air inlet 38. The lining part 138 is for instance mounted to the cover part 136 by means of a bolt (not shown) passing through a fixing hole 32 arranged in the plate of the lining part 138 and screwed in the screw hole 33 of the cover part 136. In the illustrated embodiment, the fixing hole 32 is located in the center of the plate.

When the cover part 136 and the lining part 138 are mounted by the bolt, the outer skirt 37 is sleeved outside the inner skirt 361 , with its side S facing the side S’ of the inner skirt 361 as shown in Fig.13. In addition, the height of the inner skirt 361 and the ribs 362 are dimensioned to allow them getting in contact with the plate of the lining part 138 when mounted, so that water could hardly pass through their interface with the plate of the lining part 138. As shown in Fig. 13, in this embodiment, four ribs 362 are disposed in the form of a cross with the screw hole 33 in the center. The ribs 362 form the baffles for water and/or air. It should be understood that the quantity and the distribution of the ribs may vary. When the cover part 136 and the lining part 138 are mounted, the air inlet 38 is located between two ribs 362, one of which is partially hollowed to leave an intermediate air opening 363 in the air inlet channel. Another rib adjacent to the hollowed rib is also hollowed to leave an intermediate air opening. The inner skirt 361 comprises a first notch 364 and the outer skirt 37 comprises a second notch 374 at the same location, so as to form an air opening. The first notch 364 extends on the whole height of the inner skirt 361 whilst the second notch 374 extends on a part of the height of the outer skirt 37. Preferably, as shown in Fig. 13, the outer skirt 37 comprises a block 373 protruding inwardly and is inserted in the first notch 364 of the inner skirt 361 when mounted. The first notch 364 is located between the other two ribs 362. In other words, the air inlet 38 and the air opening are located in diagonal quadrants defined by the four ribs. Thus, air entering the tank cap 135 passes firstly the air opening formed by the notches 364 and 374, then passes the intermediate air openings 363 formed in two adjacent ribs 362, and finally passes through the air inlet 38 to access the water supply tank 122. Conversely, when the water tank is tilted and the water tends to leak out through the tank cap 135, it is trapped between the cover part 136 and the lining part 138 by the baffles formed by the ribs 362 and the block 373. In another preferred embodiment, the intermediate air openings 363 may be located directly adjacent to the top surface of the cover part 136, so that they may trap the water more efficiently.

In order to lock the drain valve 127 in its closed or open position, a cam shape is formed at a top portion of the plug 128 of the drain valve 127. The top portion comprises a stepped surface including a higher surface 45 and a lower surface 46 which are connected by a cam surface 41. As shown on Fig. 14 wherein the drain valve 127 is in the open position, a lever arm 50 of the action member 126 rests on the lower surface 46 of the top of the plug 128. To switch the valve 127 to its closed position, the action member 126 should be rotated around its axis in the clockwise direction. The lever arm 50 of the action member 126 is thus pressed against the cam surface 41 by its first edge 42. When the cam surface 41 and the first edge 42 are being forced through, the lever arm 50 is moved downwards against a spring force that tends to urge the drain valve plug 128 upwards and comes to rest on the higher surface 45 of the top of the plug 128 which is thus pushed down to block the water outlet 125. Preferably, a protrusion 43 is provided on the higher surface 45 of the top portion of the plug 128, near the cam surface 41. Conversely, to open drain valve 127, the action member 126 should be rotated in the anticlockwise direction. The lever arm 50 is pressed against the protrusion 43 by its second edge 44. Only when the protrusion 43 and the second edge 44 are forced through, can the plug 128 be pushed upwards by the spring 132 and thus opens the valve 127.

The above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand and thereby implement the contents of the present invention, and the scope of protection of the present invention cannot be limited thereto. Any equivalent modifications or embellishments made in accordance with the spirit of the present invention shall be included within the scope of protection of the present invention.