Variable displacement gear pump

Abstract

A variable displacement gear pump comprises a fixed gear, a movable gear movable, a fixed gear ring fitted over the movable gear, a movable gear ring fitted over the fixed gear, a fixed cover having a hole in which the fixed gear ring rotates, a movable cover having a hole in which the movable gear ring rotates, a fixed gear block attached to the fixed cover, and a movable gear block attached to the movable cover. The fixed gear is engaged with the movable gear. The movable gear ring rotates in the hole of the movable cover, and the fixed gear ring rotates in the hole of the fixed cover. The movable gear, together with the movable cover, the movable gear, and the movable gear block, move along the direction of the shaft to change a width in which the fixed gear is engaged with the movable gear.

1 . A variable displacement gear pump, comprising:
 a fixed gear rotating in place;   a movable gear movable along a direction of a shaft;   a fixed gear ring fitted over the movable gear to be movable along the direction of the shaft;   a movable gear ring fitted over the fixed gear to be movable along the direction of the shaft;   a fixed cover having a hole in which the fixed gear ring rotates;   a movable cover having a hole in which the movable gear ring rotates;   a fixed gear block attached to the fixed cover; and   a movable gear block attached to the movable cover, wherein the fixed gear is engaged with the movable gear, wherein the movable gear ring fitted over the fixed gear rotates in the hole of the movable cover, and the fixed gear ring fitted over the movable gear rotates in the hole of the fixed cover, wherein the movable gear, together with the movable cover, the movable gear ring, and the movable gear block, move along the direction of the shaft to change a width in which the fixed gear is engaged with the movable gear to adjust the amount of a fluid discharged as the gears make one full turn.   
     
     
         2 . The variable displacement gear pump of  claim 1 , wherein the fixed gear block is replaced with a fixed casing, and the movable gear block is replaced with a movable casing. 
     
     
         3 . A variable displacement gear pump, comprising:
 a fixed gear rotating in place;   a movable gear movable along a direction of a shaft, wherein the number of teeth of the movable gear is one less than the number of teeth of the fixed gear;   a fixed gear ring fitted over the movable gear to be movable along the direction of the shaft;   a movable gear ring fitted over the fixed gear to be movable along the direction of the shaft;   a gear block having the movable gear ring fitted thereover and fitted in the fixed gear to be movable along the direction of the shaft;   a casing containing the fixed gear, the movable gear, the movable gear ring, and the gear block;   a gear ring cover having a hole in which the fixed gear ring rotates; and   a gear block cover having a hole through which the gear block enters or exits, a fluid inlet, and a fluid outlet, wherein the fixed gear is engaged with the movable gear, wherein the fixed gear ring fitted over the movable gear rotates in the hole of the gear ring cover, wherein the movable gear ring and the gear block are fitted in the fixed gear to abut a side surface of the movable gear so that the movable gear ring rotates along with the fixed gear, wherein the gear block abuts teeth tips of the fixed gear while moving through the hole of the gear block cover, and wherein the movable gear, the movable gear ring, and the gear block together move along the direction of the shaft to change a width in which the fixed gear is engaged with the movable gear to adjust the amount of a fluid discharged as the gears make one full turn.   
     
     
         4 . A variable displacement gear pump, comprising:
 a fixed gear rotating in place;   a movable gear movable along a direction of a shaft;   a fixed gear ring fitted over the movable gear to be movable along the direction of the shaft;   a movable gear ring fitted in the fixed gear to be movable along the direction of the shaft;   a gear block having a fixed crescent plate hole and fitted in the movable gear ring;   a fixed gear ring cover having a hole in which the fixed gear ring rotates and a movable crescent plate hole;   a movable crescent plate attached to the gear block;   a fixed crescent plate attached to the fixed gear ring cover; and   a casing containing the fixed gear, the movable gear, the movable gear ring, the gear block, the fixed crescent plate, and the movable crescent plate, wherein the fixed gear is engaged with the movable gear, wherein the fixed gear ring fitted over the movable gear rotates in the hole of the fixed gear ring cover, wherein the fixed crescent plate abuts the movable gear, the movable crescent plate abuts the fixed crescent plate and the fixed gear, and the movable gear ring and the gear block abut a side surface of the movable gear so that the movable gear ring rotates along with the fixed gear, and wherein the movable gear, the movable gear ring, the gear block, and the movable crescent plate together move along the direction of the shaft to change a width in which the fixed gear is engaged with the movable gear to adjust the amount of a fluid discharged as the gears make one full turn.   
     
     
         5 . The variable displacement gear pump of  claim 4 , further comprising a gear block supporting plate and a casing cover having a gear block supporting plate hole, wherein the gear block supporting plate is attached to the gear block, and the gear block supporting plate is allowed to pass through the gear block supporting plate hole in the casing cover. 
     
     
         6 . The variable displacement gear pump of  claim 1 , further comprising:
 a second movable gear movable along the direction of the shaft;   a second fixed gear ring fitted over the second movable gear to be movable along the direction of the shaft;   a second fixed cover having hole in which the second fixed gear ring rotates;   a second movable gear block attached to the movable cover, wherein the movable gear and the second movable gear connect to each other along a straight line with the movable cover disposed therebetween, wherein the second fixed gear ring fitted over the second movable gear rotates in the hole of the second fixed cover, and the movable gear ring fitted over the fixed gear rotates in the hole of the movable cover, wherein the fixed gear is engaged with the movable gear and the second movable gear, and wherein the movable gear and the second movable gear, together with the movable cover, the movable gear ring, and the movable gear block and the second movable gear block, move in the direction of the shaft to change the width in which the fixed gear is engaged with each of the movable gear and the second movable gear to adjust the amount of the fluid discharged through each outlet as the gears make one full turn.   
     
     
         7 . The variable displacement gear pump of  claim 6 , wherein the fixed gear block is replaced with a fixed casing, and the second movable gear block is replaced with a movable casing.