Abstract:
The present invention includes: a toilet pool, wherein, the toilet pool has a pool tapered from top to bottom, the bottom of the pool is a discharge outlet, the top of the pool is a tapered annular platform, the tapered annular platform consists of a wide part and a narrow part, above the tapered annular platform is a slot flush nozzle, shunts implemented by the slot flush nozzle are evenly distributed on a surface of the pool under the guide of the tapered annular platform, and the toilet pool is provided with a clean water supply means. It achieves a configuration that two flushing systems coexist on a toilet pool, achieves secondary homogenization of water currents, achieves water-saving and efficient flushing, achieves maximization of water capacity in the same space, and achieves a simple, reliable fixedly-installed toilet.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is the national phase entry of International Application No. PCT/CN2015/093950, filed on Nov. 6, 2015, which is based upon and claims priority to Chinese Patent Application No. 201510607034.1, filed on Sep. 22, 2015, the entire contents of which are incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to the technical field of sanitary wares, and particularly to a toilet with a manual pressurized piston pump and an electric pump which uses a slot nozzle to flush water. 
       BACKGROUND 
       [0003]    Flushing toilets and portable flushing toilets are increasingly more in the market; one common flushing manner is a tubular single-head, double-head and horizontal spraying form, water sources are supplied through a telescopic pneumatic pump or a hand-lift water pump, and during operation, water can come out by waiting for recovery or reciprocating multiple times to form a negative pressure. Moreover, discharge pressure cannot be increased through artificial force; another one is electric flushing, an overall battery pack and a pump body take place of a manual pump body, coexistence of multiple forms cannot be achieved, power supply is battery powered, the source is single, and different demands of users cannot be met. 
         [0004]    Further, a drain tank matching therewith cannot achieve intensification of space because the traditional rotary installed seal valve is installed outside the drain tank, another valve component is completely installed inside the drain tank, and damage of any component cannot enable replacement. 
         [0005]    Further, fixing of the traditional drain tank is achieved through surrounding lugs or complicated components installed in the bottom, and the positioning is complex. 
         [0006]    Further, a rotatable drain pipe that the traditional blow-molding drain tank is provided with cannot be completely poured out because a part of the drain pipe extends into the drain tank. 
       SUMMARY 
       [0007]    The present invention aims at solving the above problems, and provides a portable slot water-injection toilet, which, on the one hand, achieves a configuration that two flushing systems coexist on a toilet pool, achieves secondary homogenization of water currents through a slot flush nozzle internally provided with choke shunt cones and a tapered annular water-current platform, to really achieve water-saving and efficient flushing, achieves maximization of water capacity in the same space through installation of a sunk seal ring and forming of an embedded-block edge buckle, to bring about efficiency and intensification to production, storage, use and other links, and achieves a simple, reliable fixedly-installed toilet through a long-slit locating slot blow-molded at the bottom of the drain tank. On the other hand, the pump body and the valve body of the present invention achieve the aim of easy use and convenient replacement and maintenance, prolong the overall service life, and save resources. A technical solution adopted is as follows: 
         [0008]    A portable slot water-injection toilet, including: a toilet pool having a receiving cavity for receiving clean water, characterized in that: the toilet pool has a pool tapered from top to bottom, the bottom of the pool is a discharge outlet, the top of the pool is a tapered annular platform, the tapered annular platform consists of a wide part and a narrow part, above the tapered annular platform is a slot flush nozzle for shunting water currents, shunts implemented by the slot flush nozzle are evenly distributed on a surface of the pool under the guide of the tapered annular platform, and the toilet pool is further provided with a clean water supply means that can supply the clean water in the receiving cavity to the slot flush nozzle. 
         [0009]    On the basis of the above technical solution, a first choke shunt cone and a second choke shunt cone that shunt water currents of a nozzle water inlet are formed on the slot flush nozzle, a part of a first shunt shunted by the first choke shunt cone flows from the wide part of the tapered annular platform to the narrow part of the tapered annular platform along a first transverse direction, and the other part flows down along a surface of the pool like a fan along a downward direction; a part of a second shunt shunted by the second choke shunt cone flows from the wide part of the tapered annular platform to the narrow part of the tapered annular platform along a second transverse direction, and the other part flows down along the surface of the pool like a fan along a downward direction; and the first transverse direction is opposite to the second transverse direction. 
         [0010]    On the basis of the above technical solution, a third shunt cone is further formed on the slot flush nozzle, the third shunt cone is located between the first choke shunt cone and the second choke shunt cone to re-shunt downward water currents shunted by the first choke shunt cone and the second choke shunt cone, and shunts are divided into water currents in two inclined down directions: a first inclined direction and a second inclined direction. 
         [0011]    On the basis of the above technical solution, the clean water supply means is a manual supply means or an electric supply means or an integration of a manual supply means and an electric supply means, the manual supply means includes: a first pipeline and a piston pressure pump, the piston pressure pump is installed onto the toilet pool, the piston pressure pump sucks up the clean water in the receiving cavity through a water inlet of the piston pressure pump and supplies clean water to the slot flush nozzle by means of the first pipeline connected with a water outlet of the piston pressure pump, and the water inlet is provided with a one-way inlet valve; and 
         [0012]    the electric supply means includes: a sinking pump for pumping out the clean water in the receiving cavity and a second pipeline, and the sinking pump supplies clean water to the slot flush nozzle by means of the second pipeline. 
         [0013]    On the basis of the above technical solution, the manual supply means further includes a nut, a first groove is formed on the toilet pool, a first projection is formed in a corresponding position of the nut, the toilet pool and the nut are rotatably connected together through mutual snapping of the first groove and the first projection, external threads are formed on outer wall surfaces of a cylinder of the piston pressure pump, the cylinder is in a threaded connection with the nut, a first seal ring is disposed between the nut and the toilet pool, and a second seal ring is disposed between the cylinder and the nut. 
         [0014]    On the basis of the above technical solution, the manual supply means further includes a first anti-loosening means for preventing the nut from loosening and a positioning means for preventing the cylinder from rotating, the first anti-loosening means is connected with the nut and the toilet pool, the positioning means mainly consists of a positioning wedge and a connecting arm, the positioning wedge is fixed with the cylinder through the connecting arm, a pit fitting the positioning wedge is formed on the toilet pool, and the positioning wedge penetrates the pit. 
         [0015]    On the basis of the above technical solution, the toilet pool is provided with a filling port for making up water into the receiving cavity, the filling port is provided with a transitional connector having a cavity, a top outside face of the transitional connector is recessed downwards to form a filling channel for adding water, the filling channel is in communication with a top opening of the filling port and the receiving cavity, a filling port inner ring is formed on a top inside of the filling port, the transitional connector has a concave nip fitting the filling port inner ring, through matching positioning of the filling port inner ring and the concave nip, the transitional connector is detachably connected with the filling port, a water outlet joint of the sinking pump is connected with a water inlet end of the transitional connector, one end of the second pipeline is connected with a water outlet end of the transitional connector, the filling channel is not in communication with the cavity, and the water inlet end and the water outlet end of the transitional connector are in communication with the cavity. 
         [0016]    On the basis of the above technical solution, the portable slot water-injection toilet further includes a drain tank for containing sewage, the top of the drain tank is installed with an embedded valve lock nut in a rotating connection with the drain tank and a threaded seal valve in a threaded connection with the embedded valve lock nut, the threaded seal valve is in communication with the discharge outlet, a second groove is formed on the drain tank, a second projection is formed in a corresponding position of the embedded valve lock nut, the embedded valve lock nut and the drain tank are snapped together through the second groove and the second projection, a third seal ring is disposed between the embedded valve lock nut and the drain tank, a fourth seal ring is disposed between the threaded seal valve and the embedded valve lock nut, a position where the drain tank joins the embedded valve lock nut is formed hollowly towards an inner cavity direction of the drain tank to cause the threaded seal valve to sink into the drain tank, and the drain tank is provided thereon with a fixed drain outlet and/or a drain pipe in a rotating connection with the drain tank. 
         [0017]    On the basis of the above technical solution, a second anti-loosening means for preventing the embedded valve lock nut from loosening is disposed between the embedded valve lock nut and the drain tank. 
         [0018]    On the basis of the above technical solution, a third groove is formed on the drain tank, a third projection is formed in a corresponding position on an outer wall side of the drain pipe, the drain pipe and the drain tank are snapped together through the third groove and the third projection, a fifth seal ring is disposed between the drain pipe and the drain tank, a part of the drain pipe extends into the drain tank, a slope structure is disposed in an inlet position near the drain pipe on an inner wall face of the drain tank, and the highest point of the slope structure is flush with an inlet of the drain pipe. 
         [0019]    On the basis of the above technical solution, the bottom of the drain tank has a long-slit locating slot, and inside the long-slit locating slot is a clamping structure for clamping any sheet-like fixed plate or U-shaped reinforcing steel that can be inserted into the long-slit locating slot. 
         [0020]    The present invention has the following advantages: the present invention, on the one hand, achieves a configuration that two flushing systems coexist on a toilet pool, achieves secondary homogenization of water currents through a slot flush nozzle internally provided with choke shunt cones and a tapered annular water-current platform, to really achieve water-saving and efficient flushing, achieves maximization of water capacity in the same space through installation of a sunk seal ring and forming of an embedded-block edge buckle, to bring about efficiency and intensification to production, storage, use and other links, and achieves a simple, reliable fixedly-installed toilet through a long-slit locating slot blow-molded at the bottom of the drain tank. On the other hand, the pump body and the valve body of the present invention achieve the aim of easy use and convenient replacement and maintenance, prolong the overall service life, and save resources. Compared with the related products in the current market, the present invention has strong generality, and related parts in the products in the current market can be transformed by using part of the structure of the present invention, to develop new generation of products and increase the use value thereof. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    To describe the technical solutions of the embodiments of the present invention or the existing technology more clearly, the following briefly introduces the accompanying drawings required for describing the embodiments or the existing technology. Apparently, the accompanying drawings in the following description show only some embodiments of the present invention, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts. 
           [0022]      FIG. 1  is a top structural diagram of the toilet pool according to the present invention; 
           [0023]      FIG. 2  is a structural diagram of the slot flush nozzle according to the present invention; 
           [0024]      FIG. 3  is a schematic structural diagram of the manual supply means according to the present invention; 
           [0025]      FIG. 4  is a schematic structural diagram of the electric supply means according to the present invention; 
           [0026]      FIG. 5  is a sectional schematic structural diagram of the drain tank according to the present invention; 
           [0027]      FIG. 6  is a three-dimensional schematic structural diagram of the drain tank according to the present invention; 
           [0028]      FIG. 7  is a schematic structural diagram of a joint part between the discharge pipe and the drain tank according to the present invention; 
           [0029]      FIG. 8  is a sectional schematic structural diagram of a joint part between the discharge pipe and the drain tank according to the present invention; 
           [0030]      FIG. 9  is a schematic structural diagram of the bottom of the drain tank according to the present invention; 
           [0031]      FIG. 10  is a three-dimensional schematic structural diagram of the present invention; 
           [0032]      FIG. 11  is an exploded schematic structural diagram of the present invention; 
           [0033]      FIG. 12  is a three-dimensional schematic structural diagram of the transitional connector according to the present invention; and 
           [0034]      FIG. 13  is a three-dimensional schematic structural diagram of a lower drain tank. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0035]    The present invention is further described below in combination with the accompanying drawings and examples. 
         [0036]    Embodiments of the present invention are described below in detail, examples of the embodiments are illustrated in the drawings, and the same or similar reference signs from beginning to end represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are exemplary and are merely used to explain the present invention, but cannot be understood as limitations to the present invention. 
         [0037]    In the description of the present invention, it should be understood that the terms “first”, “second”, “third”, “fourth” and “fifth” are merely used for description, but cannot be understood as indicating or implying relative importance. 
         [0038]    In the description of the present invention, it should be noted that, unless expressly specified and defined, the terms “install”, “interconnect” and “connect” should be understood in a broad sense, for example, it may be a fixed connection, or a detachable connection, or an integrated connection; and may be connected directly, or be connected indirectly through a intermediate medium. For those of ordinary skill in the art, specific meanings of the terms in the present invention can be understood according to specific situations. 
         [0039]    As shown in  FIG. 1  and  FIG. 2 , a portable slot water-injection toilet, including: a toilet pool  1  having a receiving cavity  10  for receiving clean water, characterized in that: the toilet pool  1  has a pool  11  tapered from top to bottom, the bottom of the pool  11  is a discharge outlet  14 , the top of the pool  11  is a tapered annular platform  12 , the tapered annular platform  12  consists of a wide part  121  and a narrow part  123 , above the tapered annular platform  12  is a slot flush nozzle  111  for shunting water currents, shunts implemented by the slot flush nozzle  111  are evenly distributed on a surface of the pool  11  under the guide of the tapered annular platform  12 , and the toilet pool  1  is further provided with a clean water supply means that can supply the clean water in the receiving cavity  10  to the slot flush nozzle  111 . 
         [0040]    As shown in  FIG. 2 , preferably, a first choke shunt cone  118  and a second choke shunt cone  114  that shunt water currents of a nozzle water inlet  112  are formed on the slot flush nozzle  111 , a part of a first shunt shunted by the first choke shunt cone  118  flows from the wide part  121  of the tapered annular platform  12  to the narrow part  123  of the tapered annular platform  12  along a first transverse direction  119 , and the other part flows down along a surface of the pool  11  like a fan along a downward direction; a part of a second shunt shunted by the second choke shunt cone  114  flows from the wide part  121  of the tapered annular platform  12  to the narrow part  123  of the tapered annular platform  12  along a second transverse direction  113 , and the other part flows down along the surface of the pool  11  like a fan along a downward direction; in this process, if the water flow rate of the water current flowing transversely along the tapered annular platform  12  is greater than the bearing capacity of the tapered annular platform  12 , the water current will overflow, and flows downwards from the tapered annular platform  12 , and thus this process is a process of flowing along the tapered annular platform  12  while flowing downwards from the tapered annular platform  12 , so as to complete distribution of the water current on the surface of the pool  11 ; and the first transverse direction  119  is opposite to the second transverse direction  113 . 
         [0041]    Preferably, a third shunt cone  116  is further formed on the slot flush nozzle  111 , the third shunt cone  116  is located between the first choke shunt cone  118  and the second choke shunt cone  114  to re-shunt downward water currents shunted by the first choke shunt cone  118  and the second choke shunt cone  114 , and shunts are divided into water currents in two inclined down directions: a first inclined direction  117  and a second inclined direction  115 . 
         [0042]    As shown in  FIG. 3 , preferably, the clean water supply means is a manual supply means or an electric supply means or an integration of a manual supply means and an electric supply means, the manual supply means includes: a first pipeline  153  and a piston pressure pump  154 , the piston pressure pump  154  is installed onto the toilet pool  1 , the piston pressure pump sucks up the clean water in the receiving cavity  10  through a water inlet  157  of the piston pressure pump and supplies clean water to the slot flush nozzle  111  by means of the first pipeline  153  connected with a water outlet  158  of the piston pressure pump  154 , and the water inlet  157  is provided with a one-way inlet valve. 
         [0043]    This embodiment lists a specific piston pressure pump herein, the piston pressure pump mainly consists of a cylinder  151 , a handle  154 , a piston  155  and a cylinder end cover  15 , the cylinder end cover  15  is detachably connected to an open end of the cylinder  151 , the piston  155  is located in the cylinder  151 , the handle  154  passes through the cylinder end cover  15  and its bottom end is fixed to the piston  155 ; preferably, an annular slot for receiving an O-shaped ring  156  is formed on a circumferential surface of the piston  155 , and it can be understood that the protection scope of the present application should not be merely limited to such a piston pressure pump listed in this embodiment. 
         [0044]    As shown in  FIG. 4 , the electric supply means includes: a sinking pump  18  for pumping out the clean water in the receiving cavity  10  and a second pipeline  178 , and the sinking pump  18  supplies clean water to the slot flush nozzle  111  by means of the second pipeline  178 . 
         [0045]    As shown in  FIG. 3 , preferably, the manual supply means further includes a nut  16 , a first groove  116  is formed on the toilet pool  1 , a first projection is formed in a corresponding position of the nut  16 , the toilet pool  1  and the nut  16  are rotatably connected together through mutual snapping of the first groove  116  and the first projection, external threads are formed on outer wall surfaces of a cylinder  151  of the piston pressure pump, the cylinder  151  is in a threaded connection with the nut  16 , a first seal ring  161  is disposed between the nut  16  and the toilet pool  1 , and a second seal ring  168  is disposed between the cylinder  151  and the nut  16 . 
         [0046]    Optionally, the first seal ring  161  is preferably disposed below the first groove  116 , and the second seal ring  168  is preferably disposed above a position where the cylinder  151  is in a threaded connection with the nut  16 . 
         [0047]    As shown in  FIG. 3 , preferably, the manual supply means further includes a first anti-loosening means for preventing the nut  16  from loosening and a positioning means for preventing the cylinder  151  from rotating, the first anti-loosening means is connected with the nut  16  and the toilet pool  1 , the positioning means mainly consists of a positioning wedge  169  and a connecting arm  159 , the positioning wedge  169  is fixed with the cylinder  151  through the connecting arm  159 , a pit  109  fitting the positioning wedge  169  is formed on the toilet pool  1 , and the positioning wedge  169  penetrates the pit  109 . 
         [0048]    Preferably, the first anti-loosening means may be implemented by the following components: the first anti-loosening means consists of a ratchet wheel  163  fixed to the circumferential surface of the nut  16  and a pawl  103  installed on the toilet pool  1 , the pawl  103  and the ratchet wheel  163  form a ratchet wheel mechanism, the ratchet wheel mechanism enables the nut  16  only to rotate to a screwing direction, so that the nut  16  can be prevented from gradually loosening during use after being screwed; further, the pawl  103  and the ratchet wheel  163  can be fully disconnected in a manual manner, such a means of enabling the pawl  103  and the ratchet wheel  163  to be fully disconnected may adopt some existing implementation means (e.g., the pawl  103  can be lifted relative to the ratchet wheel  163  through manual drawing so as to be fully disconnected from the ratchet wheel  163 ), and thus the embodiment of the present invention makes no limitation thereto. The purpose of such design is facilitating removal of the nut  16  and ensuring that the nut  16  does not loosen without manual intervention. It can be understood that the protection scope of the present application should not be merely limited to such a first anti-loosening means limited in this embodiment. The piston pressure pump can be firmly fixed to the toilet pool  1  by rotating the nut  16 . 
         [0049]    As shown in  FIG. 4  and  FIG. 12 , preferably, the toilet pool  1  is provided with a filling port  17  for making up water into the receiving cavity  10 , the filling port  17  is provided with a transitional connector  170  having a cavity  172 , a top outside face of the transitional connector  170  is recessed downwards to form a filling channel  173  for adding water, the filling channel  173  is in communication with a top opening of the filling port  17  and the receiving cavity  10 , equivalent to that the transitional connector  170  blocks a part of the top opening of the filling port  17  and the other part not blocked is the top of the filling channel  173 , a filling port inner ring  171  is formed on a top inside of the filling port  17 , the transitional connector  170  has a concave nip  174  fitting the filling port inner ring  171 , through matching positioning of the filling port inner ring  171  and the concave nip  174 , the transitional connector  170  is detachably connected with the filling port  17 , a water outlet joint  181  of the sinking pump  18  is connected with a water inlet end  176  of the transitional connector  170 , one end of the second pipeline  178  is connected with a water outlet end  175  of the transitional connector  170 , the filling channel  173  is not in communication with the cavity  172 , and the water inlet end  176  and the water outlet end  175  of the transitional connector  170  are in communication with the cavity  172 . 
         [0050]    The second pipeline  178  can be in communication with the first pipeline  178  through, for example, a three-way valve, and the tail end of the first pipeline  178  may be connected with an elbow  152 , so as to supply water for the slot flush nozzle  111  through the flush nozzle. 
         [0051]    As shown in  FIG. 5  and  FIG. 6 , preferably, the portable slot water-injection toilet further includes a drain tank  2  for containing sewage, the top of the drain tank  2  is installed with an embedded valve lock nut  7  in a rotating connection with the drain tank  2  and a threaded seal valve  6  in a threaded connection with the embedded valve lock nut  7 , the threaded seal valve  6  is in communication with the discharge outlet  14 , a second groove is formed on the drain tank  2 , a second projection is formed in a corresponding position of the embedded valve lock nut  7 , the embedded valve lock nut  7  and the drain tank  2  are snapped together through the second groove and the second projection, a third seal ring  701  is disposed between the embedded valve lock nut  7  and the drain tank  2 , a fourth seal ring  602  is disposed between the threaded seal valve  6  and the embedded valve lock nut  7 , a position where the drain tank  2  joins the embedded valve lock nut  7  is formed hollowly towards an inner cavity direction of the drain tank  2  to cause the threaded seal valve  6  to sink into the drain tank  2 , and the drain tank  2  is provided thereon with a fixed drain outlet  202  and/or a drain pipe  8  in a rotating connection with the drain tank  2 . 
         [0052]    It can be understood that the tail end of the drain pipe  8  is detachably connected with a cover body  801 , and the threaded seal valve  6  has a specialized self-drooping handle  601 . It should be noted herein that the threaded seal valve  6  sinking into the drain tank  2  refers to that the top surface of the threaded seal valve  6  is basically flush with the top surface of the drain tank  2 , and the advantage thereof is better making use of space, to make the overall structure more intensified and implement capacity maximization with the use of the same space as a whole. 
         [0053]    Further, a second anti-loosening means for preventing the embedded valve lock nut  7  from loosening is disposed between the embedded valve lock nut  7  and the drain tank  2 . 
         [0054]    Preferably, the second anti-loosening means may be implemented by the following components: the second anti-loosening means consists of an external gear  704  fixedly connected onto a circumferential surface of the embedded valve lock nut  7  and an internal gear  204  installed on the drain tank  2 , and the external gear  704  and the internal gear  204  are engaged with each other and can be disengaged from each other. The purpose of such design is facilitating removal of the embedded valve lock nut  7  and ensuring that the embedded valve lock nut  7  does not loosen without manual intervention. It can be understood that the protection scope of the present application should not be merely limited to such a second anti-loosening means limited in this embodiment. The second anti-loosening means may also use the components of the first anti-loosening means, and likewise, the first anti-loosening means may also use the components of the second anti-loosening means. 
         [0055]    As shown in  FIG. 7  and  FIG. 8 , further, a third groove  303  is formed on the drain tank  2 , a third projection  803  is formed in a corresponding position on an outer wall side of the drain pipe  8 , the drain pipe  8  and the drain tank  2  are snapped together through the third groove  303  and the third projection  803 , a fifth seal ring  802  is disposed between the drain pipe  8  and the drain tank  2 , a part of the drain pipe  8  extends into the drain tank  2 , a slope structure  310  is disposed in an inlet position near the drain pipe  8  on an inner wall face of the drain tank  2 , and the highest point of the slope structure  310  is flush with an inlet of the drain pipe  8 , the “flush with” herein may be understood as basically flush with, which allows it to be slightly higher or lower in an appropriate amount. As shown in  FIG. 8 , if there is no slope structure  310 , as a part of the drain pipe extends into the drain tank, sewage will always be accumulated in a region sandwiched between the extending portion and the drain tank, and cannot be discharged completely, while, through the slope structure  310 , as shown in  FIG. 8 , the drain tank is rotated 90 degrees counterclockwise at first and then is rotated 90 degrees counterclockwise after most of the sewage is discharged, so the sewage can be discharged completely through the slope structure  310 , which avoids sewage accumulation. 
         [0056]    As shown in  FIG. 9 , the bottom of the drain tank  2  has a long-slit locating slot  220 , and inside the long-slit locating slot  220  is a clamping structure for clamping any sheet-like fixed plate or U-shaped reinforcing steel that can be inserted into the long-slit locating slot  220 ; the sheet-like fixed plate or U-shaped reinforcing steel is fixed onto a fixed substrate, so as to facilitate fixing of the drain tank  2 . 
         [0057]    It can be understood that, as shown in  FIG. 10  and  FIG. 11 , according to actual requirements, the portable slot water-injection toilet may further include: a seat ring  907 , a seat cover  908  and an edge buckle  902 , the drain tank  2  and the toilet pool  1  are detachably connected together by taking a locating wedge  909  as a locating basis and through the edge buckle  902 , the drain tank  2  may be provided thereon with fixed handles  201  and  310  shaped once through blow molding, and the filling port  17  is provided with a cover hat  903 . 
         [0058]    Preferably, the drain tank  2  is provided thereon with an embedded block structure  305  adopted to increase capacity. 
         [0059]    Preferably, the drain tank  2  is provided thereon with an expanded exhaust button and a liquid level display device  901 . 
         [0060]    As shown in  FIG. 13 , an optional configuration is as follows: the drain tank  2  is a lower drain tank, and may be provided thereon with a drain tank cover  800  and a fixed handle  310 , and the bottom thereof is provided with a long-slit locating slot  220 . 
         [0061]    The above description about the disclosed embodiments enables those skilled in the art to implement or use the present invention. Many kinds of modifications to the embodiments will be obvious for those skilled in the art, and the general principle defined herein can be implemented in other embodiments without departing from the principle or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will fall within the broadest scope consistent with the principle and novel characteristics disclosed herein.