Abstract:
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.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This application is a continuation in-part application of U.S. application Ser. No. 10/068,155 filed Feb. 5, 2002, now abandoned, and incorporated herein by reference in its entirety. 

   BACKGROUND OF INVENTION 
   Suction Device for Removing Pet Litter is a device for removing animal&#39;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&#39; feces are thin in consistency and are difficult to remove with the existing methods and devices. 
   The existing devices for removing pets&#39; 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&#39;s hand. Another method specified in U.S. Pat. No. 6,123,046 is to position the device under the defecating animal which is obviously uncomfortable for both the pet and the owner. 
   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 
   The presented invention is a suction device by which pet litter can be removed, regardless of its consistency. It is composed of a waste collecting container, a main cylinder with a piston, a spring positioned along the piston&#39;s axis, a mechanism for winding the spring and a trigger used for releasing the spring. The process is performed without the need for the pet&#39;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 
       FIG. 1  shows a section of the device along its length, ready for use; 
       FIG. 2  shows the details of the device used to wind the spring, as well as the trigger; 
       FIG. 3  shows the device after using; 
       FIGS. 4A ,  4 B and  4 C show different embodiments of a waste collector container; 
       FIG. 5  shows a section of the second proposed design along its length, after using the device; 
       FIG. 6  shows the device from  FIG. 5  ready for use; 
       FIG. 7  shows the device from  FIG. 5  ready for transport; 
       FIG. 8  shows the shape of washer  16 A and tube  22 A; and 
       FIG. 9  shows the shape of flange  26 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As one can see from the attached drawings, the invention consists of: 
   A waste collector container composed of a lid  1 , a plastic bag  2  and a nozzle  3 . The plastic bag is placed within a cylinder  5  and is fixed there using the lid  1 . Within the cylinder  5  is positioned a piston consisting of a gasket  6  and a piston rod  14 . In the hollow of the piston rod  14  is placed a spring  23 . The lower end of the spring  23  is attached to the gasket  6 , and its upper end is attached to a lid  13 . Along the wall of tube  22  there is a long slit through which passes the connecting rib  9 A of component  9  allowing it to be fixed to the cylindrical handle  21 . Over component  9  is placed a loading washer  20 . 
   A connecting cylinder  17  is used to connect the tube  22  and tube  19 .The connecting cylinder  17  there is a slit along its length, parallel to the slit in the tube  22 . A spring  10  is placed in the upper part of component  17 . Above the component  17  is placed a stopping washer  16 . Within the wall of tube  19  is incorporated a rib  15  A triggering mechanism  11 , comprising a body, an axis  11 A and a trigger  12  is fixed to the inside wall of tube  19  diametrically opposite to the rib  5   
   In the upper end of the piston rod  14  there is a ring  14 B, used to restrict its movement downwards when the device is being wound. 
   The winding of the spring is accomplished by moving a cylindrical handle  21  which forces the rib  9 A to press on the loading washer  20 , thus placing it out of parallel. In this way the washer is stuck in the piston rod  14  and sets it in motion, while the spring attached to the lower end of the piston rod  14  begins to stretch. When the handle  21  is returned to its initial position, the stopping washer  16  raised by the spring  10  and pressed by the rib  15  in its diametrically opposite end stops the piston rod  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 and the protecting ring  14 B reaches the stopping washer  16  and stops the devices components from disintegrating. 
   When the assembled device is positioned with the nozzle  3  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 coaxial to the piston rod  14 , thus releasing the piston rod  14 . The spring contracts and pulls up the piston, creates the necessary vacuum which sucks the material placed beneath the nozzle  3 . In the last phase of the piston&#39;s movement, a cushion mechanism is put into action. The air closed between a cylindrical portion  7 , which is fixed to the piston rod  14 , a filling washer  8  and the lower end of the tube  22 , is oozed through the looseness between the components of the cushion mechanism, thus reducing the inertia force of the piston. 
     FIGS. 4A ,  4 B and  4 C show different embodiments of a waste collector container. Each of these FIGS. illustrates a variant with respect to the configuration of the lid  1  and nozzle  3  of the waste collector, as well as the manner in which the plastic bag  2  may be attached to the lid  1  and nozzle  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. 
   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: 
   A waste collector container composed of a lid  1 A, a plastic bag  2 A and a nozzle  3 A. The plastic bag is placed within a cylinder  5 A and is fixed there using the lid  1 A. Within the cylinder  5 A is positioned a piston consisting of a gasket  6 A, and a piston rod  14 A. In the hollow of the piston rod  14 A is placed a spring  23 A. The lower end of the spring  23 A is attached to the gasket  6 A, and its upper end is attached to a cap  13 A. The cap  13 A is fixed to the upper end of the tube  22 A. Along the wall of the tube  22 A there are at least two long slots  29 . A sleeve  25  is fixed to the lower end of the tube  22 A (see FIG.  8 ). 
   To the upper end of the cylinder  5 A are fixed two flanges  26  and  28 . On the lower flat side of the flange  26  is incorporated an elastically expandable tubular portion having gripping edges  32 . To the upper flat surface of the flange  28  is jointly attached a trigger  12 A. The lower end of the trigger  12 A passes through an opening on the flat wall of the flange  28 . Between the flanges  26  and  28  is placed a washer  16 A. The washer  16 A is designed with a central opening, slightly bigger than the outer diameter of the piston rod  14 A, and concentric segmental openings through which pass the remains of the wall of the tube  22 A, as shown on FIG.  8 . Through the central openings of the flanges  26  and  28  and the segmental openings of the washer  16 A passes the tube  22 A. 
   In the drawing shown on  FIG. 7 , the tube  22 A and the piston  6 A and  14 A are placed in its lower position. In this way the upper edges of the slots  29  of the tube  22 A press on the washer  16 A forcing the spring  10 A, thus allowing the trigger  12 A to prop upon the washer  16 A In this way the piston rod  14 A gets fixed in its lower position. While the tube  22 A is being pulled up to its upper position, the sleeve  25  passes through the grasping edges  32 , and opens them up. When the sleeve  25  passes through the grasping edges  32  they contract, because of the elasticity of the tubular portion and the tube  22 A becomes fixed, the spring  23 A remains taut and device is ready for use (FIG.  6 ). When the operator presses on the outer end of the trigger  12 A, it rotates around socked joint axis. Inside end of the trigger  12 A releases the washer  16 A and allows the washer  16 A to layover on the lower flat surface of the flange  28 . The central opening of the washer  16 A becomes coaxial to the piston rod  14 A thus releasing it. The piston  6 A and  14 A, hauling by the spring  23 A, moves up and creates a vacuum, which sucks in the litter. The air contained above the piston  6 A and  14 A flows out through openings  24  located in the upper end of the cylinder  5 A. Approximately an inch before the upper position of the piston, the gasket  6 A closes the openings  24  and creates an air pillow which slows down the piston  6 A and  14 A. When the piston  6 A and  14 A reach its upper position, a cone  31  located in the base of the gasket  6 A opens up the grasping edges  32  and releases the tube  22 A (see FIG.  5 ). In this way the tube  22 A, together with the piston  6 A and  14 A can be moved to their lower positions and the procedure can be repeated. 
   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 tubular portion  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 and  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 tubular portion  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 and  14 A moves up and creates a vacuum, which sucks in the litter. The air contained above the piston  6 A and  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 and  14 A when it is stopping. When the piston  6 A and  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 and  14 A can be moved to lower terminating position and the whole procedure can be repeated.