A vacuum pump for pet litter comprises a housing and a litter container at one end of the housing. A piston is located in the housing which reciprocates between a first position and a second position wherein movement of the piston from the first position to the second position produces a vacuum in the litter container. The pump includes a spring for urging the piston towards the second position, a handle for moving the piston to the first position and a holding member which holds the piston at the first position. Operation of a release trigger permits the piston to move from the first to the second position.

CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is a continuation in-part application of U.S. application Ser. No. 10/068,155 filed Feb. 5, 2002, and incorporated herein by reference in its entirety. 
     
    
     
       BACKGROUND OF INVENTION  
         [0002]    Vacuum Pump for Pet Litter Removing is a device for removing animal's feces from grass surfaces, pavements and other public areas. The present invention is constructed in such a way that it is capable of removing the waste regardless of its consistency. Often, especially when having digestion difficulties, pets' feces are thin in consistency and are difficult to remove with the existing methods and devices.  
           [0003]    The existing devices for removing pets' waste address the problem only partially. The most popular way is to dispose manually with the help of a plastic bag wrapped around the owner's hand. Another method specified in U.S. Pat. No. 6,123,046 is to position the device under the defecating animal which obviously uncomfortable for both the pet and the owner.  
           [0004]    The device described in U.S. Pat. No 4,078,838, consists of a telescopic tube containing a plunger. In the upper end of the plunger a spiral spring is positioned. In the lower end of the plunger there is a slot where a plastic bag specially produced to fit the plunger is placed. When the plunger moves upwards, the plastic bag is drawn in the telescoping tube and is supposed to take the feces it is placed upon with it. This design makes the device difficult to use because the friction between the bag and the feces is not sufficient, especially if the latter is with slight consistency.  
         BRIEF SUMMARY OF THE INVENTION  
         [0005]    The presented invention is a vacuum pump with which pet litter can be removed, regardless of its consistency. It is composed of a waste collecting container, main cylinder with a piston, a spring positioned along the piston's axis, a mechanism for winding the spring and trigger used for releasing the spring. The process is performed without the need for the pet's owner to bend over and touch the feces. The use of vacuum allows the device to be efficient regardless of the consistency of the animal litter and the surface area: grass, bushes, or road surface. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    [0006]FIG. 1 shows a section of the device along its length, ready for use;  
         [0007]    [0007]FIG. 2 shows the details of the device used to wind the spring, as well as the trigger;  
         [0008]    [0008]FIG. 3 shows the device after using;  
         [0009]    [0009]FIGS. 4A, 4B and  4 C show different embodiments of a waste collector container;  
         [0010]    [0010]FIG. 5 shows a section of the second proposed design along its length, after using the device;  
         [0011]    [0011]FIG. 6 shows the device from FIG. 5 ready for use;  
         [0012]    [0012]FIG. 7 shows the devise from FIG. 5 ready for transport;  
         [0013]    [0013]FIG. 8 shows the shape of washer  16 A and tube  22 A; and  
         [0014]    [0014]FIG. 9 shows the shape of flange  26 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0015]    As one can see from the attached drawings, the invention consists of:  
         [0016]    A waste collector container composed of a lid  1 , plastic bag  2  and vacuum tube  3 . The plastic bag is placed within the cylinder  5  and is fixed there using the lid  1 . Within the cylinder  5  is positioned a piston consisting of gasket  6  and a tube  14 . In the hollow of the tube  14  is placed a spring  23 , its lower end attached to the gasket  6 , and its upper end attached to a lid  13 . Along the wall of the tube  22  there is a long slit through witch the connecting rib  9 A of component  9  passes allowing it to be fixed to the cylindrical handle  21 . Over component  9  is placed the loading washer  20 .  
         [0017]    The connecting cylinder  17  has a slit along its length, parallel to the slit in the tube  22 . It is used to connect tube  22  and the tube  19 . In the upper part of component  17  a spring  10  is placed. Above component  17  is placed the stopping washer  16 . Within the wall of tube  19  is incorporated rib  15  and diametrically opposite to it is the triggering mechanism  11 , comprising a body, axis and trigger  12 .  
         [0018]    In the upper end of tube  14  there is a ring  14 B, used to restrict its movement downwards when the device is being wound.  
         [0019]    The winding of the spring is accomplished by moving the cylindrical handle  21  which forces the rib  9 A to press one of the ends of the loading washer, thus taking it out of parallel. This way the washer is stuck in the tube  14  and starts moving it, while the spring in its lower end begins to stretch. When the handle is returned in its initial position, stopping washer  16  raised by the spring  10  and pressed by the rib  15  in its opposite end stops the tube  14  and does not allow the spring  23  to return the piston in its initial position. This process is repeated several times, depending on the size of the device until the spring has been wound fully when the protecting ring  14 B reaches washer  16  and stops the devices components from disintegrating.  
         [0020]    When the assembled device is positioned with the hose upon the feces and the trigger is pressed, the axis  11 A presses the washer  16  upon the face of the connecting component and makes its opening parallel to the tube  14 , thus releasing it. The spring contracts and pulls the piston and the gasket, creates the necessary vacuum which sucks the material placed beneath the hose  3 . In the last phase of the piston's movement, cushion mechanism is put into action. The air closed between the piston  7 , the filling washer  8  and the lower end of the tube  22 , is oozed in the looseness between the components of the cushion mechanism, thus reducing the inertia force of the stopping main piston.  
         [0021]    In the variant of the container described above, the lid  1 , the vacuum tube  3  and the plastic bag  2  are discarded after use. FIG. 4 shows another variant of the container where the plastic bag  2  is glued to the vacuum tube  3  and a flange  3 A is attached to it. After use, only the parts that have been in contact with the feces—the bag and the tube are discarded, the lid stays permanently in its place.  
         [0022]    [0022]FIGS. 4A, 4B and  4 C show different embodiments of a waste collector container. Each of these figures illustrates a variant with respect to the configuration of the lid  1  and tube  3  of the waste collector, as well as the manner in which the plastic bag  2  may be attached to the lid  1  and tube  3  in a number of different ways. These are intended to be example illustrations only and any suitable manner for attachment is possible within the scope of the invention.  
         [0023]    Another possible design configuration for the invention is shown in FIGS. 5, 6,  7 ,  8  and  9 . As one can see from the drawings, the invention consists of:  
         [0024]    A waste collector container composed of a lid  1 A, plastic bag  2 A and vacuum tube  3 A. The plastic bag is placed within the cylinder  5 A and is fixed there using the lid  1 A. Within the cylinder  5 A is positioned a piston consisting of gasket  6 A and a tube  14 A. In the hollow of the tube  14 A is placed a spring  23 A, its lower end attached to the gasket  6 A, and its upper end attached to a cap  13 A, attached to the upper of the tube  22 A.  
         [0025]    In the upper end of the cylinder  5 A are located two flanges  26  and  28 . Between them is placed washer  16 A, designed as shown on FIG. 8. Through the outer openings of the flanges  26  and  28  passes the tube  22 A.  
         [0026]    Along the walls of the tube  22 A there are long slots  29 , through which pass the extensions of washer  16 A, as it can be seen on FIG. 8. To the lower end of the tube  22 A is attached inflexibly a cylinder  25 . The handle  27  is attached to the cylinder  5 A. On the drawing shown on FIG. 7, the tube  22 A and the piston  6 A- 14 A are placed in lower terminating position. Thus, the measurements of the device are minimized and it is suitable for transportation. This way the slots  29  in the wall of the tube  22 A are pressuring the washer  16 A forcing the spring  10 A, thus allowing the trigger  12 A to prop up the washer  16 A from the one side. This way the tube  14 A is fixed in its lower terminating position. When the tube  22 A is pulled to its upper terminating position, the cylinder  25  opens up the grasping edges in the lower end of the flange  26 ; the tube  22 A is fixed, the spring  23 A remains taut and device is ready for use (FIG. 6). The pressing of the trigger  12 A allows the washer  16 A to lay over the flange  28  and this way its opening become parallel to the tube  14 A thus releasing it. The piston  6 A- 14 A moves up and creates a vacuum, which sucks in the litter. The air contained above the piston  6 A- 14 A is released through the openings  24  in the upper part of the cylinder  5 A. Just before the upper terminating position is reached, the gasket  6 A closes this openings and the air pillow that is formed slows down the piston  6 A- 14 A when it is stopping. When the piston  6 A- 14 A is in its upper terminating position, the cone  31  located in the base of the gasket  6 A opens up the grasping edges  32  of the flange  26  and releases the tube  22 A (see FIG. 5). In this way the tube  22 A, together with the piston  6 A,  14 A can be moved to lower terminating position and the whole procedure can be repeated.