Abstract:
A mobile liquid conveying apparatus includes a service liquid area ( 10 ) having a service liquid outlet ( 18 ) for communicating with the power tool ( 4 ), a dirty liquid area ( 12 ) having a dirty liquid inlet ( 28 ) through which dirty liquid from the power tool ( 4 ) can flow into the dirty liquid area ( 12 ) with both the service liquid area and the dirty liquid area being provided in a common storage space ( 7 ), and a separation element for separating the service liquid area ( 10 ) from the dirty liquid area ( 12 ).

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates to a liquid conveying apparatus for a power tool such as a cutting, drilling or grinding tool and which is constructed as a mobile unit and serves to supply rinsing liquid or cooling liquid and to carry off dirty liquid produced at the power tool during operation, for example, in the form of sludge water. For this purpose, the liquid conveying apparatus has a service liquid outlet, a dirty liquid inlet, and a storage volume having a service liquid area which can be connected with respect to flow to the service liquid outlet, and a dirty liquid area which can be connected with respect to flow to the dirty liquid inlet. The service liquid area is separated from the dirty liquid area. 
         [0003]    2. Description of the Prior Art 
         [0004]    Mobile liquid conveying apparatuses of the type mentioned above have the advantage that they are easy to transport so that it is possible to provide cooling liquid in a flexible manner and to eliminate dirty liquid simultaneously. 
         [0005]    A liquid conveying apparatus for rock drilling tools which is constructed as a mobile unit is known from DE 212 463. It has a receptacle with a storage volume which is divided by a filter wall into a dirty water area and a service water area. Accordingly, service water that is used for cooling and rinsing can be pumped out of the service water area to the rock drilling machine. The sludge-containing service water then travels along a hose as dirty water to the dirty water area of the receptacle. 
         [0006]    However, the known device is disadvantageous in that it is often impossible to find a suitable pore size for the filter which ensures a sufficient quality of the service water made available by the recurring filtration while at the same time preventing clogging of the filter and resulting lack of service water. 
       SUMMARY OF THE INVENTION 
       [0007]    It is the object of the present invention to overcome the above-mentioned disadvantages in a mobile liquid conveying apparatus and to increase the quantity and quality of the available service liquid. 
         [0008]    According to the invention, the above-stated object is met by a mobile liquid conveying apparatus, wherein the service liquid area and the dirty liquid area are provided in a common storage space and are separated from one another by a separating element whose position can be changed. This makes it possible to use at least approximately the total storage volume for storing fresh service liquid at the start of the operation, while the dirty liquid area is substantially first formed when dirty liquid actually occurs in operation. In this way, the limited storage volume available in the mobile liquid conveying apparatuses can be used in an optimal manner and the entire storage volume is available for receiving service liquid, e.g., drinking water, at the start of operation. 
         [0009]    In a particularly preferred embodiment form, the position of the separating element can be changed depending on a volume proportion of service liquid to a volume proportion of dirty liquid. In this way, the storage volume can be divided equally at any time during operation depending on the respective proportion of service liquid and dirty liquid. 
         [0010]    The separating element is advantageously at least partially permeable. Therefore, it is possible to reclaim a portion of the used service liquid from the dirty liquid area by filtration. 
         [0011]    The separating element is advantageously formed by an at least partially flexible receptacle. A flexible receptacle of this type makes it possible to divide the storage volume into the service liquid area and the dirty liquid area depending upon volume in a particularly simple manner. 
         [0012]    In this respect, it is advantageous when the service liquid outlet is arranged in the receptacle. In this way, the receptacle can be used to store the service liquid, while a base outlet enabling a particularly convenient disposal of dirty liquid from the storage volume, e.g., into a waste water duct, can be provided at the rest of the liquid conveying apparatus, particularly at a bottom. 
         [0013]    As an alternative to the above, the receptacle can advantageously be charged from the dirty liquid inlet. Accordingly, the dirty liquid area is extensively separated from the rest of the liquid conveying apparatus resulting in reduced contamination thereof. 
         [0014]    The receptacle is advantageously held in the rest of the liquid conveying apparatus so as to be removable, so that the liquid conveying apparatus can also be used alternatively purely as a rinsing liquid supply device or dirty liquid discharge device and as an intermediate storage for pumping through rinsing liquid to the drilling device or dirty liquid to a waste water device such as a waste water duct. 
         [0015]    In this respect, it is particularly advantageous when the receptacle is formed by a disposable receptacle so that, for example, the dirty liquid can be disposed of along with the receptacle. 
         [0016]    Further, it is advantageous when the receptacle has a floatable bottom so that it can be positioned in a predetermined manner within the storage volume. Obstruction of inlets to or outlets from the storage volume can be prevented in this way, for example. 
         [0017]    It is advantageous when the receptacle is formed by a bag to keep production costs for the receptacle as low as possible. 
         [0018]    The novel features of the present invention, which are considered as characteristic for the invention, are set forth in the appended claims. The invention itself, however, both as to its construction and its mode of operation, together with additional advantages and objects thereof, will be best understood from the following detailed description of preferred embodiment, when read with reference to the accompanying drawings. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    The drawings show: 
           [0020]      FIG. 1  a partially cross-sectional schematic view of an assembly including a liquid conveying apparatus according to the present invention and a power tool; 
           [0021]      FIG. 2  a schematic view of the assembly according to  FIG. 1  at the start of an operation; 
           [0022]      FIG. 3  a schematic view of the assembly according to  FIG. 1  toward the end of the operation; 
           [0023]      FIG. 4  a partially cross-sectional schematic view of an assembly including another embodiment of liquid conveying apparatus according to the present invention and a power tool according to  FIG. 1  at the start of an operation; 
           [0024]      FIG. 5  a schematic view of the assembly according to  FIG. 4  during an operation; 
           [0025]      FIG. 6  a schematic view of the assembly according to  FIG. 4  toward the end of an operation; 
           [0026]      FIG. 7  a schematic view of the assembly according to  FIGS. 1 to 3  in a pump-through operation; and 
           [0027]      FIG. 8  a schematic view of the assembly according to  FIGS. 4 to 6  in a pump-through operation. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0028]      FIG. 1  shows a mobile liquid conveying apparatus  2  which serves to supply a power tool  4  in the form of a diamond core drill device with a service liquid B, particularly water. The relatively clean service liquid B is used, for example, to rinse or cool a working tool or work area. The liquid conveying apparatus  2  serves at the same time to carry off a dirty liquid S which occurs during the operation of the power tool  4  and which is substantially includes the used service liquid B and material particles M removed during operation. 
         [0029]    For this purpose, the liquid conveying apparatus  2  has a storage receptacle  8  which can be closed by a cover  6  and which forms a storage space  7  in which a service liquid area  10  and a dirty liquid area  12  are provided. A flexible receptacle  14  in the form of a bag which is held in the storage receptacle  8  and which contains the service liquid area  10  serves as a separating element to separate the two areas  10 ,  12 . 
         [0030]    A float tap  16  of a service liquid outlet, designated in its entirety by  18 , projects into the receptacle  14  and is connected to a drainage pump  20  in the form of a compression pump. The service liquid B is supplied to the power tool  4  via a supply line  22  from the service liquid area  10  during operation by means of this drainage pump  20 , as is illustrated by arrows. 
         [0031]    After flowing through a work area  24  of the power tool  4 , the resulting dirty liquid S is carried away from the work area  24  by a disposal line  26  as is illustrated by arrows. For this purpose, the disposal line  26  is connected to a dirty liquid inlet  28  which opens into the dirty liquid area  12 . The entire storage space  7  and accordingly also the dirty liquid area  12  can be evacuated by means of a suction pump  30 . Due to the vacuum created in this way, the dirty liquid S is transported into the dirty liquid area  12  via the dirty liquid inlet  28  during operation. 
         [0032]    The two pumps  20 ,  30  are controlled during operation by means of a control device  32  to which a power supply cable  34  of the power tool  4  is also connected. 
         [0033]      FIG. 2  shows the liquid conveying apparatus  2  before the start of an operation. At this time, the receptacle  14  is completely filled with the relatively clean service liquid B, for example, service water or drinking water. A float bottom  36  of the receptacle  14 , which is formed, for example, from material which is relatively resistant to bending compared to the rest of the receptacle  14  and which has air pores, contacts the receptacle bottom  38  of the storage receptacle  8 . The service liquid area  10  occupies virtually the entire storage space  7  of the storage receptacle  8 , while the dirty liquid area  12  has a minimum volume and does not yet have dirty liquid S. 
         [0034]    When the power tool  4  is turned on, the drainage pump  20  is also started under the control device  32  and now supplies the service liquid B to the power tool  4  from the service liquid area  10  via the supply line  22 . Further, the suction pump  30  which generates a vacuum in the storage space  7  is also started by means of the control device  32 . As a result, the dirty liquid S occurring in the work space  14  is conducted to the dirty liquid inlet  28  through which the dirty liquid area  12  is now filled. 
         [0035]    In accordance with the view in  FIG. 1 , the dirty liquid area  12  is progressively filled during operation, while the volume of the service liquid B in the service liquid area  10  progressively decreases. As a result of the level of dirty liquid in the dirty liquid area  12  increases the level of the clean service liquid decreases, and the float bottom  36  gradually floats upward. 
         [0036]    This process continues until the service liquid area  10  is completely empty as is shown in  FIG. 3 . As a result of the buoyancy of the float bottom  36 , the receptacle  14  floats on the dirty liquid S which now almost completely fills the storage space  7 . At this time, the service liquid area  10  has a minimum volume. 
         [0037]    Before further operation of the liquid conveying apparatus  2 , the dirty liquid S must first be removed. This is carried out by means of a base outlet  40  which is provided at the receptacle bottom  38  and through which the dirty liquid S can be conveyed, for example, to a disposal device  42 , e.g., a waste water duct. 
         [0038]      FIGS. 4 to 6  show an alternative embodiment of the liquid conveying apparatus  2  which essentially corresponds to the embodiment according to  FIGS. 1 to 3 . Identical elements or elements having the same function are therefore designated in a corresponding manner. 
         [0039]    The essential difference of this embodiment from the embodiment shown in  FIGS. 1-3  consists in the construction and apparatus of the service liquid outlet  18  and dirty liquid inlet  28 . The dirty liquid inlet  28  is arranged in such a way that the receptacle  14  can now be charged through it. Accordingly, in this embodiment, the dirty liquid area  12  is arranged inside the receptacle  14 , while the rest of the volume of the storage space  7  is used as the service liquid area  10 . 
         [0040]      FIG. 4  shows the liquid conveying apparatus  2  again before the start of operation. At this time, the service liquid area  10  is completely filled with the relatively clean service liquid B. The receptacle  14 , which at this time is still empty, floats to the top of the service liquid B due to the buoyancy of the float bottom  36 . The dirty liquid area  12  accordingly has a minimum volume. 
         [0041]    When the power tool  4  is switched on, the drainage pump  20  is also started by means of the control device  20  and now conveys the service liquid B from the service liquid area  10  to the power tool  4  via the supply line  22 . For this purpose, the service liquid outlet  18  is arranged next to the receptacle bottom  38  in this embodiment. 
         [0042]    Further, the suction pump  30  is also started by means of the control device  32  and generates a vacuum in the storage space  7 . As a result, the dirty liquid S, which is produced in the work space  14 , is transported to the dirty liquid inlet  28  through which it fills the dirty liquid area  12  in the receptacle  14 . 
         [0043]    According to  FIG. 5 , the receptacle  14  or dirty liquid area  12  is progressively filled during operation, while the volume of the service liquid B in the rest of the storage space  7 , i.e., in the service liquid area  10 , progressively decreases. As a result of this, the level of dirty liquid in the receptacle  14  increases inversely to the level of the service liquid and the float bottom  36  progressively sinks. 
         [0044]    This process continues until the service liquid area  10  is almost completely empty, as shown in  FIG. 6 . As a result of the high level of the dirty liquid in relation to the minimum level in the service liquid area  10 , the float bottom  36  of the receptacle  14  contacts the receptacle bottom  38 . At this time, the service liquid area  10  has a minimum volume. 
         [0045]    As can be seen particularly from  FIGS. 5 and 6 , the receptacle  14  can have a permeable area  46  at an upper end  44 . This permeable area  46  contains pores which are dimensioned in such a way that the service liquid B contained in the dirty liquid S can outlet from the dirty liquid area  12  in this area  46 , while the material particles M are retained in the receptacle  14  for the most part. To this end, a certain pressure difference between the dirty liquid S and the service liquid B, which occurs as a result of the buoyancy of the float bottom  36  in connection with a certain bending resistance of the receptacle  14  and particularly when the level of service liquid B is very low, is used. In this way, a portion of the occurring dirty liquid S is filtered and can be used to refill the service liquid area  10 . 
         [0046]    To dispose of the dirty liquid S, which is collected in the dirty liquid area  12 , the receptacle  14  is held in the liquid conveying apparatus  2  so as to be removable and is formed by a disposable receptacle such as, e.g., a disposable bag. The receptacle  14  can accordingly be removed from the liquid conveying apparatus  2  and disposed of, together with the dirty liquid S contained therein. A new receptacle  14  can then be inserted in the liquid conveying apparatus  2 , and the service liquid area  10  can be filled with fresh service liquid B. 
         [0047]    An additional advantage of the removable receptacle  14  consists in that the liquid conveying apparatus  2  can be used for pumping through service liquid B or dirty liquid S by means of a simple alteration, as shown in  FIGS. 7 and 8 . 
         [0048]      FIG. 7  shows the liquid conveying apparatus  2  according to  FIGS. 1 to 3 , wherein the receptacle  14  is removed, and the float tap  16  has been replaced by a suction tube  48  at the service liquid outlet  18 , with the suction tube  48  extending almost to the receptacle bottom  38 . Further, the supply line  22  is now connected to the disposal device  42  instead of to the power tool  4 . 
         [0049]    In this instance, a vacuum is generated in the storage space  7  by the suction pump  30  during operation of the liquid conveying apparatus  2  and, as a result, the dirty liquid S produced in the work area  14  is aspirated via the disposal line  26 . The dirty liquid S which is transported in this way into the storage space  7 , which functions as an intermediate storage, is then pumped via the supply line  22  to the disposal device  42  by means of the drainage pump  20  which is formed for this purpose by a pump suitable for the dirty liquid. 
         [0050]      FIG. 8  shows the liquid conveying apparatus  2  according to  FIGS. 4 to 6 , wherein the receptacle  14  is again removed, and the disposal line  26  is now connected to a supply device  50 , e.g., in the form of a drinking water connection, rather than to the work area  14 . 
         [0051]    In this case, a vacuum can be generated in the storage space  7  during operation of the liquid conveying apparatus  2  by means of the suction pump  30  in order to assist in conveying service liquid B from the supply device  50 . The service liquid B transported in this way into the storage space  7 , which functions as an intermediate storage, and is then pumped via the supply line  22  to the power tool  4  by means of the drainage pump  20 . 
         [0052]    Though the present invention was shown and described with references to the preferred embodiment, such is merely illustrative of the present invention and is not to be construed as a limitation thereof and various modifications of the present invention will be apparent to those skilled in the art. It is therefore not intended that the present invention be limited to the disclosed embodiment or details thereof, and the present invention includes all variations and/or alternative embodiments within the spirit and scope of the present invention as defined by the appended claims.